Skin microbiota and human 3D skin models

Abstract

Although the role of the microbiota in skin homeostasis is still emerging there is growing evidence that an intact microbiota supports the skin barrier. The increasing number of research efforts that are trying to shed more light on the human skin-microbiota interaction require the use of suitable experimental models. Three-dimensional (3D) skin equivalents have been established as a valuable tool in dermatological research because they contain a fully differentiated epidermal barrier that reflects the morphological and molecular characteristics of normal human epidermis. In this review we provide an overview of current 3D skin models and illustrate the potential of 3D skin models to study the human skin-microbiota interplay.

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Issue Information - Cover and Editorial Board

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Issue Information - TOC

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p.Glu477Lys mutation in keratin 5 is not necessarily mortal in generalized severe epidermolysis bullosa simplex

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STING activation enhances cetuximab-mediated NK cell activation and DC maturation and correlates with HPV+ status in head and neck cancer

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Shanhong Lu, Fernando Concha-Benavente, Gulidanna Shayan, Raghvendra M. Srivastava, Sandra P. Gibson, Lin Wang, William E. Gooding, Robert L. Ferris
ObjectivesThe intracellular DNA sensor stimulator of interferon genes (STING) has recently been shown to play a vital role in anti-viral and anti-tumor immune responses stimulating cytokine production. While human papillomavirus (HPV) is a causative agent for a subset of head and neck squamous cell carcinoma (HNSCC) with unique etiology and clinical outcome, how the STING pathway is regulated in a virus-induced tumor microenvironment is not well understood. Since STING inactivation likely reflects immunoescape via innate immunity, we hypothesized that its restoration would improve efficacy of the immune modulatory monoclonal antibody (mAb), cetuximab.Materials and methodsWe correlated STING protein expression with clinical parameters by immunohistochemistry (n = 106) and its mRNA expression from The Cancer Genome Atlas (TCGA) in HNSCC tissue specimens. STING protein expression was tested for association with cancer-specific survival (CSS). We further examined the impact of STING activation on cetuximab-mediated immunity using an in vitro NK:DC:tumor cells co-culture system.ResultsIn this study, we found that expression of STING both at the protein and mRNA level was higher in HPV positive (HPV⁺) specimens but unrelated to TNM stage or cancer-specific survival. Our in vitro studies verified that STING activation enhanced cetuximab mediated NK cell activation and DC maturation.ConclusionOur findings suggest a novel role of STING in HPV-related carcinogenesis, in which activation of the STING signaling pathway may facilitate anti-tumor response in HNSCC patients, particularly in combination with therapeutic monoclonal antibodies (mAbs) such as cetuximab, an epidermal growth factor receptor (EGFR) inhibitor.



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Heterogeneity and irregularity of pretreatment 18F-fluorodeoxyglucose positron emission tomography improved prognostic stratification of p16-negative high-risk squamous cell carcinoma of the oropharynx

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Nai-Ming Cheng, Yu-Hua Dean Fang, Din-Li Tsan, Li-Yu Lee, Joseph Tung-Chieh Chang, Hung-Ming Wang, Shu-Hang Ng, Chun-Ta Liao, Lan-Yan Yang, Tzu-Chen Yen
ObjectivesHuman papillomavirus-negative oropharyngeal squamous cell carcinoma (OPSCC) has unfavorable survival outcomes. Two outcomes have been identified based on smoking history and tumor stage. We investigate the prognostic role of pre-treatment positron emission tomography (PET) in high-risk OPSCC.Materials and MethodsWe enrolled 147 M0 OPSCC patients with p16-negative staining and a history of heavy smoking (>10 pack-years) or T4 disease. All patients completed primary chemoradiotherapy, and 42% maximum standard uptake values (SUVmax) were used as the threshold for primary tumor. Patients were classified into training and validation cohorts with a ratio of 1:1.5 according to the PET date. Heterogeneity and irregularity indices were obtained. PET parameters with significant impact on progression-free survival (PFS) in receiver operating characteristic curves and univariate Cox models were identified and included in recursive partitioning analysis (RPA) for constructing a prognostic model. The RPA-based prognostic model was further tested in the validation cohort using multivariate Cox models.ResultsFifty-eight and 89 patients were in the training and validation groups, respectively. Heterogeneity parameter, SUV-entropy (derived from histogram analysis), and irregularity index, and asphericity were significantly associated with PFS. The RPA model revealed that patients with both high SUV-entropy and high asphericity experienced the worst PFS. Results were confirmed in the validation group. The overall concordance index for PFS of the model was 0.75, which was higher than the clinical stages, performance status, SUVmax, and metabolic tumor volume of PET.ConclusionsPET prognostic model provided useful prediction of PFS for patients with high-risk OPSCC.

Graphical abstract

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Podoplanin emerges as a functionally relevant oral cancer biomarker and therapeutic target

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Edward P. Retzbach, Stephanie A. Sheehan, Evan M. Nevel, Amber Batra, Tran Phi, Angels T.P. Nguyen, Yukinari Kato, Soly Baredes, Mahnaz Fatahzadeh, Alan J. Shienbaum, Gary S. Goldberg
Oral cancer has become one of the most aggressive types of cancer, killing 140,000 people worldwide every year. Current treatments for oral cancer include surgery and radiation therapies. These procedures can be very effective; however, they can also drastically decrease the quality of life for survivors. New chemotherapeutic treatments are needed to more effectively combat oral cancer. The transmembrane receptor podoplanin (PDPN) has emerged as a functionally relevant oral cancer biomarker and chemotherapeutic target. PDPN expression promotes tumor cell migration leading to oral cancer invasion and metastasis. Here, we describe the role of PDPN in oral squamous cell carcinoma progression, and how it may be exploited to prevent and treat oral cancer.



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Oncologic and functional outcomes of pretreatment tracheotomy in advanced laryngeal squamous cell carcinoma: A multi-institutional analysis

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Serena A. Byrd, Mary J. Xu, Lauren M. Cass, Daniel J. Wehrmann, Matthew Naunheim, Kara Christopher, John J. Dombrowski, Ronald J. Walker, Lori Wirth, John Clark, Paul Busse, Annie Chan, Daniel G. Deschler, Kevin Emerick, Derrick T. Lin, Mark A. Varvares
ObjectivesDescribe the influence of pretreatment tracheotomy and treatment modality (surgical versus non-surgical) on oncologic and functional outcomes.Materials and methodsRetrospective study of previously untreated advanced-stage laryngeal squamous cell carcinoma patients at two academic tertiary care institutions from 1995 to 2014.ResultsPrimary outcomes evaluated were disease-free survival, disease-specific survival, and overall survival of pretreatment tracheotomy versus no pretreatment tracheotomy cohorts. Functional status, measured by tracheotomy decannulation and gastrostomy tube placement/removal, was assessed. Of the 226 patients, 31.4% underwent pretreatment tracheotomy. Five-year disease-specific survival was 72.9%, and overall survival was 48.8% for entire cohort. There was a statistically significant decrease in overall survival (p = .03) and disease-free survival (p = .02) for the pretreatment tracheotomy group compared to no pretreatment tracheotomy, which was largely explained by primary tumor stage. Pretreatment tracheotomy was associated with gastrostomy tube placement and was an independent predictor of worse odds of gastrostomy tube removal. Disease stage, distant metastasis, and age independently conferred worse odds of gastrostomy tube removal.ConclusionPatients undergoing pretreatment tracheotomy for primary T4 laryngeal cancer had decreased overall survival compared to patients without pretreatment tracheotomy. There was no difference in local recurrence rates based on tracheotomy status. Organ preservation with chemotherapy and radiation did not result in better functional outcomes than surgery in the pretreatment tracheotomy group as nearly half of patients treated with organ preservation remained tracheotomy dependent. Based on this data, pretreatment tracheotomy may impact oncologic and functional outcomes in advanced disease, and it should be a consideration in an informed decision-making process.



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Role of sequential chemoradiotherapy in stage II and low-risk stage III–IV nasopharyngeal carcinoma in the era of intensity-modulated radiotherapy: A propensity score-matched analysis

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Cheng Xu, Rui Sun, Ling-Long Tang, Lei Chen, Wen-Fei Li, Yan-Ping Mao, Guan-Qun Zhou, Rui Guo, Ai-Hua Lin, Ying Sun, Jun Ma, Wei-Han Hu
ObjectivesTo investigate the role of sequential chemoradiotherapy (SCRT; induction chemotherapy [IC] followed by intensity-modulated radiotherapy [IMRT]) in stage II and low-risk stage III–IV nasopharyngeal carcinoma (NPC).Materials and methodsFour well-matched groups were individually generated using propensity score matching in patients (n = 689) with stage II (SCRT vs. concurrent chemoradiotherapy [CCRT], SCRT vs. IMRT alone) and low-risk stage III–IV NPC (SCRT vs. CCRT, SCRT vs. IC + CCRT). Five-year overall/disease-free/locoregional relapse-free/distant metastasis-free survival (OS/DFS/LRRFS/DMFS) and acute hematological toxicities were compared between groups. The value of SCRT was further investigated in multivariate analysis and subgroup analysis by adjusting for covariates and limiting IC-to-IMRT time interval, respectively.ResultsSCRT led to equivalent survival outcomes compared to CCRT/IMRT alone and CCRT/IC + CCRT in stage II and low-risk stage III–IV NPC, respectively (all P > .050). In multivariate analysis, patients with stage II NPC treated by SCRT obtained higher DMFS (AHR = 0.22, 95% CI = 0.05–1.00, P = .050), but not OS, DFS or LRRFS, compared to patients receiving CCRT; non-significant differences were observed between SCRT and other treatments. SCRT with short IC-to-IMRT time interval (≤70 days) achieved higher 5-year survival rates than IMRT alone (DMFS: P = .046), CCRT (stage II NPC; OS: P = .047; DMFS: P = .020) and IC + CCRT (DFS: P = .041). Moreover, SCRT was associated with higher, equivalent and lower frequencies of acute hematological toxicities than IMRT alone, CCRT and IC + CCRT, respectively.ConclusionSCRT is mainly beneficial in stage II NPC, leading to better DMFS and/or equivalent acute hematological toxicities compared to CCRT/IMRT alone. CCRT is still the best choice for low-risk stage III–IV NPC.



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Baseline peripheral blood leukocytosis: Biological marker predicts outcome in oropharyngeal cancer, regardless of HPV-status

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Zeno A.R. Gouw, Jan Paul de Boer, Arash Navran, Michiel W.M. van den Brekel, Jan-Jakob Sonke, Abrahim Al-Mamgani
ObjectivesTo study the prognostic value of abnormalities in baseline complete blood count in patients with oropharyngeal cancer (OPC) treated with (chemo) radiation.Methods and materialsThe prognostic value of baseline complete blood count on outcome in 234 patients with OPC treated between 2010 and 2015 was examined in multivariate analysis together with other conventional prognostic variables including HPV-status, tumor stage, tumor and nodal size.ResultsThe 3-year overall survival (OS), disease-free survival (DFS), locoregional control (LRC), and distant control (DC) of the whole group were 74%, 64%, 79%, and 88%, respectively. Leukocytosis and HPV-status were the only significant prognosticators for OS and DFS at the multivariate analysis. Patients without leukocytosis had a significantly better DC compared to those with leukocytosis (92% and 70%, respectively, p < 0.001). Patients with HPV-negative OPC had significantly worse LRC compared to HPV-positive patients (67% and 90%, respectively, p < 0.001). The 3-year OS in HPV-positive group with leukocytosis compared to those without leukocytosis were 69% and 95%, respectively (p < 0.001). The figures for HPV-negative patients were 41% vs. 61%, respectively (p = 0.010).ConclusionsThis is the first study to date reporting the independent impact of leukocytosis and HPV-status on outcome of patients with OPC. The poor outcome of patients with leukocytosis is mainly caused by the worse DC. The significant impact of leukocytosis on outcome was even more pronounced in HPV-positive patients. These biomarkers could help identifying patients with poor prognosis at baseline requiring intensification of local and/or systemic treatment while treatment de-intensification might be offered to the low-risk group.



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Induction chemotherapy followed by concurrent chemoradiation versus concurrent chemoradiation alone in the definitive management of p16-positive oropharyngeal squamous cell carcinoma with low-neck or N3 disease

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Onita Bhattasali, Jeannie Han, Lester D.R. Thompson, Gary L. Buchschacher, Iman A. Abdalla, Shawn Iganej
ObjectiveThe addition of induction chemotherapy (ICT) to concurrent chemoradiation (CCRT) has been investigated as a method of improving outcomes among patients with locally advanced head and neck squamous cell carcinoma. Previous studies have consisted of heterogeneous populations with both p16-positive and p16-negative disease and varying extent of nodal disease burden. We evaluated the role of ICT in p16-positive oropharyngeal squamous cell carcinoma (OPSCC) at high-risk of distant failure.Materials and methodsA retrospective review was conducted of 88 consecutive patients with p16-positive OPSCC with low-neck and/or N3 lymphadenopathy. Among these patients, 44 received ICT followed by CCRT, and 44 received CCRT alone with concurrent agents including Cisplatin, Carboplatin, and Cetuximab. Disease control and survival outcomes were reported after adjusting for age, T stage, N stage, and smoking status.ResultsMedian follow-up for surviving patients was 47 (range: 13–115) months. Patients who received CCRT alone were older than those who received ICT (61 years vs. 56 years; p = 0.02); the groups were otherwise similarly balanced. 3-year distant metastasis: 38% vs. 18% (adjusted hazard ratio (HR) = 0.32 [0.13–0.82]; p = 0.02). 3-year progression-free survival: 49% vs. 74% (adjusted HR = 0.46 [0.22–0.93]; p = 0.03). 3-year overall survival: 67% vs. 83% (adjusted HR = 0.48 [0.21–1.12]; p = 0.09).ConclusionAmong patients with p16-positive OPSCC with low-neck and/or N3 lymphadenopathy, ICT followed by CCRT may reduce the risk for distant failure over CCRT alone and lead to improved progression-free survival. Future trials should concentrate on patients at the highest risk of distant metastasis in order to appropriately assess the benefit of ICT.



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Phosphorylation of PI3K regulatory subunit p85 contributes to resistance against PI3K inhibitors in radioresistant head and neck cancer

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Myung Woul Han, In Sun Ryu, Jong Cheol Lee, Song Hee Kim, Hyo Won Chang, Yoon Sun Lee, Seulkina Lee, Seong Who Kim, Sang Yoon Kim
Objectives: PI3K/Akt/mTOR pathway is commonly activated in most cancers and is correlated with resistance to anticancer therapies such as radiotherapy. Therefore, PI3K is an attractive target for treating PI3K-associated cancers. Material and Methods: We investigated the basal expression and the expression after treatment of PI3K inhibitor or Src inhibitor of PI3K/Akt pathway-related proteins in AMC-HN3, AMC-HN3R, HN30 and HN31 cells by performing immunoblotting analysis. The sensitivity to PI3K inhibitors or Src inhibitor was analyzed by MTT assay and clonogenic assay. To determine the antitumoral activity of combination treatment with PI3K inhibitor and Src inhibitor, we used using xenograft mouse model. Results: We found that PI3K regulatory subunit p85 was predominantly phosphorylated in radioresistant head and neck cancer cell line (HN31), which showed resistance to PI3K inhibitors. Next, we investigated mechanism through which PI3K p85 phosphorylation modulated response to PI3K inhibitors. Of note, constitutive activation of Src was found in HN31 cells and upon PI3K inhibitor treatment, restoration of p-Src was occurred. Src inhibitor improved the efficacy of PI3K inhibitor treatment and suppressed the reactivation of both Src and PI3K p85 in HN31 cells. Furthermore, downregulation of PI3K p85 expression by using a specific siRNA suppressed Src phosphorylation. Conclusions: Together, our results imply the novel role of the PI3K regulatory subunit p85 in the development of resistance to PI3K inhibitors and suggest the presence of a regulatory loop between PI3K p85 and Src in radioresistant head and neck cancers with constitutively active PI3K/Akt pathway.



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Comparison of clinical, radiological and morphological features including the distribution of HPV E6/E7 oncogenes in resection specimens of oropharyngeal squamous cell carcinoma

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Hani Ibrahim Channir, Katalin Kiss, Niclas Rubek, Jane Andersen, Jeanette Bæhr Georgsen, Gulla Søby Rathje, Birgitte Wittenborg Charabi, Christian von Buchwald, Christel Bræmer Lajer
BackgroundHuman papillomavirus (HPV)-driven oropharyngeal squamous cell carcinoma (OPSCC) represents a distinct tumour entity in comparison to HPV-negative OPSCC. The clinical, radiological, morphological features and distribution of HPV E6/E7 mRNA were investigated in resected specimens of OPSCC.MethodsWe retrieved formalin-fixed, paraffin-embedded whole section slides from 24 p16/HPV-DNA positive and 18 p16/HPV-DNA negative primary tumours and 16 corresponding metastases in patients with early-stage OPSCC who underwent planned curative or diagnostic primary transoral robotic surgery. A detailed clinicoradiological and histopathological investigation of the tumours was performed along with detection of HPV E6/E7 mRNA by in situ hybridisation.ResultsHPV-driven OPSCC was characterised by non-keratinising morphology and was dominated by a cohesive invasion pattern at the leading edge of the tumour. Dysplastic zones of the squamous epithelium were strictly located in the tonsillar crypts in contrast to HPV-negative OPSCC which predominantly arised from the dysplastic surface epithelium. Thirteen HPV-driven OPSCC invaded through the tonsillar lymphoid compartment and into soft tissue, causing a stromal desmoplastic reaction. HPV mRNA was consistently but inhomogenously expressed in the entire tumour area and in the dysplastic squamous epithelium. There was no HPV expression in the adjacent normal epithelium and in the non-neoplastic tissues.ConclusionsThis study enhances the current understanding of HPV-driven OPSCC. Only tumours that invade through the lymphoid compartment induce a stromal desmoplastic reaction. A consistent but inhomogenous expression of E6 and E7 mRNA was found in tumour and dysplastic areas, emphasizing that the E6/E7 oncogenes are the driving factors in HPV-driven OPSCC.



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Do we need a different staging system for tongue and gingivobuccal complex squamous cell cancers?

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Piyush Gupta, Jocelyn C. Migliacci, Pablo H. Montero, Daniella Karassawa Zanoni, Jatin P. Shah, Snehal G. Patel, Ian Ganly
ObjectivesTo determine the need for a separate staging system for gingivobuccal complex squamous cell cancers (GBCSCC) based on 5-year overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) data from one institution.Patients and methodsAn Institutional Review Board (IRB)-approved retrospective analysis was performed on an oral cavity cancer patient database. Patients from 1985 to 2012 with primary surgical treatment for biopsy-proven squamous cell cancer (SCC) from either the oral tongue (TSCC Group) or gingivobuccal complex (GBCSCC Group), were selected as two separate subgroups. The clinicopathologic data were used to stage the patients based on the American Joint Committee on Cancer 7th edition. Survival outcomes including 5-year OS, RFS, and DSS were calculated and analyzed. A multivariate analysis was performed to identify if subsite was an independent predictor for the survival outcomes, adjusting for other variables. A p-value of less than .05 was considered statistically significant.Results936 patients with TSCC and 486 patients with GBCSCC were considered eligible for the analysis. Patients with GBCSCC were more likely to be older (p < .001) and presented with more advanced disease (p < .001) compared to patients with TSCC. Unadjusted hazard ratio (HR) suggested GBCSCC had poor OS compared to TSCC. However, after adjusting for other variables, the adjusted HR was not significant (p = .593). There was no difference in 5-year DSS or RFS in either of the study groups.ConclusionWith similar survival outcomes by stage, there is no justification for using a different staging system for GBCSCC.



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Evaluating oropharyngeal carcinoma with transcervical ultrasound, CT, and MRI

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Farhoud Faraji, Stephanie F. Coquia, Meghan B. Wenderoth, Ericka S. Padilla, Dana Blitz, M. Robert DeJong, Nafi Aygun, Ulrike M. Hamper, Carole Fakhry
ObjectiveTo compare transcervical ultrasonography (US) to standard cross-sectional imaging for the visualization of human papillomavirus-related oropharyngeal cancer (HPV-OPC).Materials and methodsPatients with HPV-OPC and available standard imaging (CT and/or MRI) were identified in clinic and prospectively enrolled. US was performed to visualize the oropharynx and lymph nodes. Tumor characteristics across imaging modalities were evaluated (CT versus MRI, and US versus standard imaging (SI)).ResultsForty-three patients were included. The overall blinded detection rates for CT and MRI were 83% and 71%, respectively. The unblinded detection rate for US was 98%. Agreement of tumor anatomic subsite was moderate for both CT vs MRI (κ = 0.59) and US vs SI (κ = 0.47). Comparison of tumor size by CT and MRI showed statistically significant correlations in craniocaudal (CC), anteroposterior (AP), and mediolateral (ML) dimensions (RhoCC = 0.51, pCC = 0.038; RhoAP = 0.81, pAP < 0.0001; RhoML = 0.57, pML = 0.012). Tumor size estimates by US and SI showed statistically significant correlations in CC and AP, but not ML (RhoCC = 0.60, pCC = 0.003; RhoAP = 0.71, pAP < 0.0001; RhoML = 0.30, pML = 0.08). Tumor volume estimates improved correlations between US and SI (Rho = 0.66, p < 0.0001). Stratification of US patients into early and late imaging studies demonstrated an increase in correlation strength from early (Rho = 0.32, p = 0.32) to late groups (Rho = 0.77, p < 0.0001) demonstrating that ultrasound accuracy improved with experience.ConclusionsOur findings suggest that transcervical ultrasonography is a sensitive and relatively accurate adjunct to standard imaging for the evaluation of oropharyngeal tumors. Its cost, portability, and potential for in-clinic and serial imaging render US an attractive modality to further develop for imaging oropharyngeal tumors.



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Identification of a gene expression signature predicting survival in oral cavity squamous cell carcinoma using Monte Carlo cross validation

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): John Schomberg, Argyrios Ziogas, Hoda Anton-Culver, Trina Norden-Krichmar
ObjectivesThis study aims to identify a robust signature that performs well in predicting overall survival across tumor phenotypes and treatment strata, and validates the application of Monte Carlo cross validation (MCCV) as a means of identifying molecular signatures when utilizing small and highly heterogeneous datasets.Materials and methodsRNA sequence gene expression data for 264 patient tumors were acquired from The Cancer Genome Atlas (TCGA). 100 iterations of Monte Carlo cross validation were applied to differential expression and Cox model validation. The association between the gene signature risk score and overall survival was measured using Kaplan-Meier survival curves, univariate, and multivariable Cox regression analyses.ResultsPathway analysis findings indicate that ligand-gated ion channel pathways are the most significantly enriched with the genes in the aggregated signature. The aggregated signature described in this study is predictive of overall survival in oral cancer patients across demographic and treatment strata.ConclusionThis study reinforces previous findings supporting the role of ion channel gating, interleukin, calcitonin receptor, and keratinization pathways in tumor progression and treatment response in oral cancer. These results strengthen the argument that differential expression of genes within these pathways reduces tumor susceptibility to treatment. Conducting differential gene expression (DGE) with Monte Carlo cross validation, as this study describes, offers a potential solution to decreasing the variability in DGE results across future studies that are reliant upon highly heterogeneous datasets. This improves the ability of studies reliant upon similarly structured datasets to reach results that are reproducible.



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Submental artery island flap versus free flap reconstruction of lateral facial soft tissue and parotidectomy defects: Comparison of outcomes and patient factors

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Akshay V. Patel, Jason E. Thuener, Kate Clancy, Mustafa Ascha, Nauman F. Manzoor, Chad A. Zender
ObjectivesThe submental artery island flap (SIF) has recently been described in temporal bone defects. At our institution we have broadened the application of the SIF and modified the harvest technique for complex lateral facial and skull base defects. Our primary aim is to evaluate the outcomes of patients undergoing complex lateral facial soft tissue, parotidectomy, and temporal bone defects who are reconstructed with the SIF to a similar cohort undergoing free tissue transfer reconstruction.Materials and methodsNineteen patients undergoing SIF and 54 patients undergoing free tissue flaps for oncologic lateral facial, parotidectomy and temporal bone defects were retrospectively identified. Comparative statistics were used to analyze variables between the two cohorts, specifically operative time, flap size, length of stay, regional recurrence, disease free survival, and overall survival.ResultsNo significant difference in demographic and disease related variables was observed. Operative time was significantly lower in SIF group with mean of 412.9 (SD 93.4) minutes compared to 544.1 (SD 139.9) minutes in free flap group. Flap size was significantly larger in free tissue transfer, 32.4 (SD 17.5) cm² (SIF) compared to mean area of 105.2 (SD 53.2) cm² (Free tissue transfer). A significant difference in length of stay was also noted between groups. There was no regional recurrence of disease in level I–III in SIF group. There was no significant difference in DFS or OS between the two groups.ConclusionSIF is an oncologically sound option for reconstruction of lateral facial soft tissue, parotidectomy, and temporal bone defects.



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Refining the eighth edition AJCC TNM classification and prognostic groups for papillary thyroid cancer with lateral nodal metastasis

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Hye In Kim, Kyunga Kim, So Young Park, Jun-Ho Choe, Jung-Han Kim, Jee Soo Kim, Young Lyun Oh, Soo Yeon Hahn, Jung Hee Shin, Hyeon Seon Ahn, Sun Wook Kim, Tae Hyuk Kim, Jae Hoon Chung
BackgroundIn the eighth edition, TNM staging system omits location of nodal metastasis as a criterion for staging patients with papillary thyroid cancer (PTC). Accordingly, all of non-metastatic N1b PTC patients are classified as stage I or II solely according to an age-cutoff of 55 years. We hypothesized that incorporating other lymph node (LN) factors into TNM staging system would better predict cancer-specific mortality (CSM) in N1b patients.MethodsWe enrolled 745 N1b PTC patients without distant metastasis. Alternative prognostic LN factors and cut-off points were assessed using Cox regression and time-dependent ROC analysis. Alternative prognostic groupings were derived based on minimal hazard differences for CSM among groups stratified by LN risk and age. We assessed accuracy of CSM prediction.ResultsLateral LN ratio (LNR) >0.3 and largest LN size >3 cm were prognostic factors for CSM. Stage II patients (eighth edition) with LN risk (lateral LNR >0.3 or largest LN size >3 cm) had a much higher CSM rate (20.9%) than those in the same stage without LN risk (3.2%). Alternative prognostic grouping (Group 1, <55 years without LN risk; Group 2, <55 years with LN risk or ≥55 years without LN risk; and Group 3, ≥55 with LN risk) achieved higher proportions of variance explained (PVEs) for predicting CSM (10.7%) than those of the eighth edition TNM staging system (4.8%).ConclusionsThe proposed grouping for N1b patients using LN risk can distinguish patients with poor prognosis from those with good prognosis better than the eighth edition TNM staging system.



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Proteome analysis reveals that de novo regenerated mucosa over fibula flap-reconstructed mandibles resembles mature keratinized oral mucosa

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Vinay V. Kumar, Bonney L. James, Manuela Ruß, Stefan Mikkat, Amritha Suresh, Peer W. Kämmerer, Michael O. Glocker
AimThe aim of this study was to determine whether intra-oral de novo regenerated mucosa (D) that grew over free fibula flap reconstructed-mandibles resembled the donor tissue i.e. external skin (S) of the lateral leg, or the recipient site tissue, i.e. keratinized oral mucosa (K).Materials and methodsDifferential proteome analysis was performed with ten tissue samples from each of the three groups: de novo regenerated mucosa (D), external skin (S), and keratinized oral mucosa (K). Expression differences of cornulin and involucrin were validated by Western blot analysis and their spatial distributions in the respective tissues were ascertained by immunohistochemistry.ResultsFrom all three investigated tissue types a total of 1188 proteins were identified, 930 of which were reproducibly and robustly quantified by proteome analysis. The best differentiating proteins were assembled in an oral mucosa proteome signature that encompasses 56 differentially expressed proteins. Principal component analysis of both, the 930 quantifiable proteins and the 56 oral mucosa signature proteins revealed that the de novo regenerated mucosa resembles keratinized oral mucosa much closer than extra-oral skin. Differentially expressed cornification-related proteins comprise proteins from all subclasses of the cornified cell envelope. Prominently expressed in intra-oral mucosa tissues were (i) cornifin-A, cornifin-B, SPRR3, and involucrin from the cornified-cell-envelope precursor group, (ii) S100A9, S100A8 and S100A2 from the S100 group, and (iii) cornulin which belongs to the fused-gene-protein group.ConclusionAccording to its proteome signature de novo regenerated mucosa over the free fibula flap not only presents a passive structural surface layer but has adopted active tissue function.



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Prognostic significance and optimal candidates of primary tumor resection in major salivary gland carcinoma patients with distant metastases at initial presentation: A population-based study

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Xiao Shi, Fan Dong, Wenjun Wei, Kehan Song, Naisi Huang, Zhongwu Lu, Bowen Lei, Pengcheng Yu, Wanlin Liu, Yu Wang, Guohua Sun, Yulong Wang, Qinghai Ji
ObjectivesTo investigate the prognostic significance and identify optimal candidates of primary tumor resection (PTR) for patients with metastatic major salivary gland carcinoma (MaSGC) at diagnosis.Materials and methodsPatients with metastatic MaSGC were identified from the Surveillance, Epidemiology and End Results (SEER) database. Kaplan-Meier analyses, log-rank tests and multivariate Cox regression models were employed to evaluate the therapeutic roles of PTR in the overall cohort and different subgroups.ResultsOverall, 255 patients were included in our study, among whom 80 (31.4%) received PTR. PTR was associated with decreased overall mortality (OM) and cancer-specific mortality (CSM) in the overall cohort (PTR vs No-PTR, HR: 0.363, 95%CI: 0.204–0.646, p = .001 for OM; HR: 0.439, 95%CI: 0.243–0.794, p = .006 for CSM). When we focused on site-specific metastases, receipt of PTR significantly reduced the risk of OM for patients with lung, bone or distant lymph node involvement (all p < .05), whereas this surgical procedure not only failed to bring survival benefit, but even seemed to insignificantly increase the mortality risk once liver metastases were presented (PTR vs No-PTR, HR: 1.109, 95%CI: 0.279–4.412 for OM; HR: 1.596, 95%CI: 0.364–7.004 for CSM). In addition, subgroup analyses showed that patients with stage T1-3 disease, younger age (<65), single-site metastases and high-risk pathologies might benefit from PTR.ConclusionOur study for the first time verifies the favorable prognostic impact of PTR for highly-selected patients with metastatic MaSGC at diagnosis and has the potential to be adopted in future clinical practice, although long-term prospective studies are warranted.



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Neck recurrence in clinically node-negative oral cancer: 27-year experience at a single institution

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Aviram Mizrachi, Jocelyn C. Migliacci, Pablo H. Montero, Sean McBride, Jatin P. Shah, Snehal G. Patel, Ian Ganly
ObjectivesNeck failure in patients with oral squamous cell carcinoma (OSCC) carries a poor outcome, yet the management of patients who initially present with clinically node-negative (cN0) neck is not clearly defined.Patients and methodsRetrospective review of patients with cN0 OSCC treated at Memorial Sloan Kettering Cancer Center from 1985 to 2012, focusing on rate, pattern and predictors of neck failure, salvage treatment, and survival outcomes.ResultsOf 1,302 patients, 806 (62%) underwent elective neck dissection (END) and 496 (38%) had observation. 190 patients (15%) developed neck recurrence. Median follow-up was 58.5 months (range 1–343); 5-year neck recurrence-free survival (NRFS) was 85% and 80% for the END and observation group respectively (p = .06). Patients with neck failure had poorer outcomes than patients without neck failure (5-year overall survival, 37% vs. 74% [p < .001]; disease-specific survival [DSS], 41% vs. 91% [p < .001]). Independent predictors of neck failure were smoking, primary tumor subsite (hard palate and upper gum), and extranodal extension. 87% of patients underwent salvage treatment (END: 81.1%; observation: 94%). Salvage surgery with adjuvant (chemo) radiation had better DSS than surgery alone or nonsurgical salvage.ConclusionsIn our cohort of patients with initially cN0 OSCC triaged to END vs. observation using clinical parameters, 15% developed neck failure. Salvage treatment was feasible in most cases but survival was poorer compared to patients without neck failure. Surgery followed by adjuvant (chemo) radiation resulted in the best outcome.



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Combination of post-operative radiotherapy and cetuximab for high-risk cutaneous squamous cell cancer of the head and neck: A propensity score analysis

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Joshua D. Palmer, Charles J. Schneider, Neil Hockstein, Alexandra L. Hanlon, Jordan Silberg, Jon Strasser, Elizabeth A. Mauer, Michael Dzeda, Robert Witt, Adam Raben
ObjectivesThe objective of this study was to investigate the safety, tolerability and preliminary efficacy of radiotherapy plus cetuximab in high risk CSCC patients.Materials and MethodsPatients with high-risk CSCC diagnosed between 2006 and 2013 were analyzed. Patients were divided into two groups: radiotherapy alone versus radiotherapy plus cetuximab. Among 68 patients meeting study criteria, we identified 29 treated with cetuximab plus RT and 39 with RT alone. Primary analysis examined disease-free and overall survival, freedom from local and distant recurrence in the propensity score matched cohort. Propensity score analysis was performed with weighted factors including: Charlson Comorbidity Index score, age. KPS, primary location, T and N stage, recurrent status, margin status, LVSI, PNI and grade. Toxicity was assessed using the CTCAE v4.0.ResultsMedian follow-up for living patients was 30 months. Patients in the cetuximab group were more likely to have advanced N stage, positive margins and recurrent disease. After propensity score matching the groups were well balanced. Six patients experienced ≥ grade 3 acute toxicity in the cetuximab group. The 1-year, 2-year and 5-year progression free survival (PFS) for patients in the cetuximab group were 86%, 72% and 66%, respectively. The 1-year, 2-year and 5-year overall survival (OS) for patients in the cetuximab group was 98%, 80% and 80%, respectively.ConclusionsAlthough limited by small numbers, the combination of cetuximab and radiotherapy in CSCC appears well tolerated there were more long-term survivors and less distant metastasis in the cetuximab group. These promising finding warrant further studies.



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Pitfalls of post-treatment PET after de-intensified chemoradiotherapy for HPV-associated oropharynx cancer: Secondary analysis of a phase 2 trial

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): Kyle Wang, Terence Z. Wong, Robert J. Amdur, William M. Mendenhall, Nathan C. Sheets, Rebecca Green, Brian D. Thorp, Samip N. Patel, Trevor G. Hackman, Adam M. Zanation, Mark C. Weissler, Bhishamjit S. Chera
ObjectivesWe evaluated patterns of nodal response and positive predictive value (PPV) of 3 month post-treatment PET in patients with HPV-associated oropharyngeal cancer treated on a multi-institutional de-intensification trial.Materials and methodsEligibility criteria included: (1) T0-3, N0-2c, M0, (2) HPV+/p16+ oropharyngeal squamous cell carcinoma, and (3) ≤10 pack-years smoking or ≤30 pack-years and abstinent ≥5 years. Patients received 60 Gy radiation alone (T0-2, N0-1) or with concurrent weekly cisplatin 30 mg/m² and surveillance PET three months post-radiation. Nodal responses were categorized as complete (CR), equivocal (ER), or incomplete (IR) using both local and central radiographic review. A "true positive" was ER/IR with clinical/radiographic progression or positive pathology.Results79 node-positive pts (84% N2) were analyzed. Distribution of nodal CR, ER, and IR was 44 (56%), 27 (34%), and 8 (10%), respectively. 29 (37%) had ER/IR in pre-treatment node-positive neck levels, whereas 14 (18%) had ER/IR in pre-treatment node-negative levels. Of patients with ER/IR, 5 were observed clinically, 19 received repeat imaging, and 11 received either biopsy (1) or neck dissection (10). The PPV was 9% for ER/IR and 13% for IR, with 3 patients found to have persistent disease on neck dissection. There was no difference in nodal relapse rate in patients with nodal CR vs. nodal ER/IR.ConclusionPost-treatment PET may not accurately predict the presence of persistent disease in patients with favorable-risk oropharynx cancer. These results support close surveillance rather than surgical evaluation in most favorable-risk patients.



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Comparison between magnetic resonance and computed tomography in detecting mandibular invasion in oral cancer: A systematic review and diagnostic meta-analysis

Publication date: March 2018
Source:Oral Oncology, Volume 78
Author(s): José de Souza Brandão Neto, Felipe Toyama Aires, Rogério Aparecido Dedivitis, Leandro Luongo Matos, Claudio Roberto Cernea
BackgroundSuspicion of mandibular invasion directly influences perioperative strategy, requiring marginal or segmental mandibulectomy, or reconstruction in some cases. This has a considerable impact on outcome and quality of life. The aim of this study was to evaluate the accuracy of magnetic resonance and computed tomography in the prediction of mandibular invasion in patients with oral cavity cancer.MethodA systematic review was conducted, including diagnostic studies comparing magnetic resonance imaging with computed tomography in the prediction of bone invasion. Sensitivity, specificity, positive and negative likelihood values and summary receiver operating characteristic (sROC) curves were calculated.ResultsThe electronic and manual search identified 346 articles. Of these, 11 studies were included in the systematic review for a total of 477 patients. The sensitivity, specificity, and positive and negative likelihood values for MRI were 78%, 86%, 5.29 and 0.23, respectively. For CT, they were 76%, 89%, 6.00 and 0.28, respectively. The sROC curves for MRI and CT were 82.3% and 82.5%, respectively.ConclusionNo superiority was observed between the diagnostic methods regarding mandibular invasion detection.



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Clinical efficacy of oral administration of finasteride at a dose of 2.5 mg/day in women with female pattern hair loss

Abstract

Female pattern hair loss (FPHL) presents with diffuse thinning over the mid-frontal scalp, for which various treatment modalities have been tried. Although currently, oral 5 α-reductase inhibitors such as finasteride are being used, their clinical efficacy remains controversial. We retrospectively investigated 544 premenopausal or postmenopausal patients with FPHL who were prescribed finasteride at a dose of 2.5 mg/day. Our study excluded patients with a follow-up period of < 3 months and patients who were prescribed other FPHL treatment modalities including topical minoxidil. Finally, 112 patients were evaluated based on their medical records and clinical photographs. Based on assessment using the Ludwig scale at the time of their initial visit, among 112 patients studied, 59 patients were classified as belonging to grade I, 47 were grade II, and 6 were grade III. Using global photographs, we found that 33 (29.5%) of the 112 patients studied showed slight improvement, 73 (65.2%) showed significant improvement, whereas no change was recorded in 6 (5.4%). We could demonstrate efficacy of administration of finasteride at a dose of 2.5 mg/day for patients with FPHL and also found that finasteride has a better effect on hair growth when patients had a lower Ludwig score and an older age at onset

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The efficacy of botulinum neurotoxin A in the treatment of plaque psoriasis

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Desmoplastic transformation of a nodular melanoma arising from a speckled lentiginous nevus

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Monitoring of immunoglobulin A antibodies to epidermal and tissue transglutaminases over an 18-month period in a Japanese patient with dermatitis herpetiformis

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Promising therapeutic option for cutaneous plasmacytosis: 308-nm excimer lamp

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Inflammatory Biomarkers During Bacterial Acute Rhinosinusitis

Abstract

Purpose of Review

Diagnosis of bacterial acute rhinosinusitis is difficult. Several attempts have been made to clarify the diagnostic criteria. Inflammatory biomarkers are easily obtainable variables that could shed light on both the pathophysiology and diagnosis of bacterial acute rhinosinusitis. The purpose of this review article is to assess literature concerning the course of inflammatory biomarkers during acute rhinosinusitis and the use of inflammatory biomarkers in diagnosing bacterial acute rhinosinusitis.

Recent Findings

We included C-reactive protein, erythrocyte sedimentation rate, white blood cell counts, procalcitonin, and nasal nitric oxide in this review and found that especially elevated C-reactive protein and erythrocyte sedimentation rate are related to a higher probability of a bacterial cause of acute rhinosinusitis. Still, normal levels of these two biomarkers are quite common as well, or the levels can be heightened even during viral respiratory infection without suspicion of bacterial involvement.

Summary

Elevated levels of C-reactive protein or erythrocyte sedimentation rate support diagnosis of bacterial acute rhinosinusitis, but due to a lack of sensitivity, they should not be used to screen patients for bacterial acute rhinosinusitis.

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Cutaneous Manifestations of Reactions to Biologics

Abstract

Purpose of Review

The goal of this paper is to review the major adverse cutaneous reactions that have been reported to the most commonly used biologics.

Recent Findings

Anti-TNF agents and immune checkpoint inhibitors have significant, immune-mediated cutaneous manifestations that can necessitate discontinuation. Anti-TNF agents, IL-6 inhibitors, and IL-12/23 inhibitors can paradoxically cause psoriasis flares or unmask previously undiagnosed psoriasis. IL-17 inhibitors are unique in increasing risk for Candida infections. Benign injection site reactions, non-specific rash, cellulitis, and hypersensitivity reactions are relatively common adverse events.

Summary

A wide variety of cutaneous reactions caused by biologics have been reported, ranging from benign injection site reactions to life-threatening cutaneous reactions necessitating discontinuation of the implicated biologic agent.

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Novel splice site mutation in the LIPH gene in a patient with autosomal recessive woolly hair/hypotrichosis: Case report and published work review

Abstract

Autosomal recessive woolly hair is a relatively rare hereditary hair disorder characterized by sparse, short, curly hair. This condition is known to be caused by mutations in the LIPH gene, LPAR6 gene or KRT25 gene. In the Japanese population, most patients with autosomal recessive woolly hair carry one of two founder mutations in the LIPH gene, c.736T>A (p.Cys246Ser) or c.742C>A (p.His248Asn). However, occasionally, individuals with this condition carry compound heterozygous mutations, typically one founder mutation and another mutation. In this study, we describe a patient with a compound heterozygous mutation in the LIPH gene at c.736T>A and c.1095-3C>G. The latter mutation created a novel splice site. This was the fourth splice site mutation to be described in the LIPH gene. Furthermore, we performed an in vitro transcription assay in cultured cells, and demonstrated that the c.1095-3C>G mutation led to a frame-shift, which created a premature termination codon at the protein level (p.Glu366Ilefs*7). Finally, we summarized the mutations previously reported for the LIPH gene. Our findings provide further clues as to the molecular basis of autosomal recessive woolly hair.

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Safety and efficacy of nivolumab in Japanese patients with malignant melanoma: An interim analysis of a postmarketing surveillance

Abstract

A postmarketing surveillance study is ongoing to evaluate nivolumab treatment for Japanese patients with malignant melanoma and accumulate data on all adverse events (AE) and efficacy. In this interim analysis, we evaluated data from approximately 100 Japanese medical institutions obtained from the nivolumab approval date in Japan (4 July 2014) through 3 July 2016. Patients were monitored during the first 12 months of treatment. Nivolumab was administrated by i.v. infusion (2 mg/kg every 3 weeks). A total of 680 and 610 patients were evaluated for safety and efficacy, respectively. The incidences of adverse drug reactions (ADR) and grade 3 or higher ADR were 53.53% and 12.35%, respectively. Predominant ADR included hypothyroidism (11.32%) and abnormal enzyme activity, such as increase of aspartate aminotransferase (7.79%), alanine aminotransferase (6.76%), alkaline phosphatase (6.18%) and γ-glutamyltransferase (5.44%). Grade 3 or higher ADR of special interest with an incidence of 1% or higher were hepatic function disorder (2.50%), colitis/diarrhea (2.06%) and infusion reaction (1.32%). No cases of encephalitis or venous thromboembolism, other AE of special interest, were observed. The estimated median overall survival was 379 days (95% confidence interval [CI], 290–not reached [NR]) in the overall population, NR (95% CI, 305–NR) for cutaneous melanoma and 340 days (95% CI, 275–NR) for mucosal melanoma. The improvement rate based on the antitumor response at the last evaluation was 22.2% (131/590 patients). No new safety concerns were raised, and serious ADR of special interest were infrequent. Nivolumab showed equivalent efficacy in patients with mucosal melanoma and those with cutaneous melanoma.

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Pharmacokinetics of second-line anti-tuberculosis drugs in children with multidrug-resistant tuberculosis in India [PublishAheadOfPrint]

We studied the pharmacokinetics of levofloxacin (LFX), pyrazinamide (PZA), ethionamide (ETH) and cycloserine (CS) in children with multidrug-resistant tuberculosis (MDR TB) being treated according to the Revised National TB Control Programme (RNTCP) guidelines in India. This observational, pharmacokinetic study was conducted in 25 children with MDR TB at the Sarojini Naidu Medical College, Agra, India who were being treated with a 24-month daily regimen. Serial blood samples were collected after directly observed administration of drugs. Estimation of plasma LFX, PZA, ETH and CS were undertaken according to validated methods by HPLC. Adverse events were noted at six months of treatment. The peak concentration (C_max) of LFX was significantly higher in female than male children (11.5μg/ml vs 7.3μg/ml; p = 0.017). Children below 12 years had significantly higher exposure (AUC_0-8) of ETH than those above 12 years of age (17.5μg/ml.h vs 9.4μg/ml; p = 0.030). Multiple linear regression analysis showed significant influence of gender on C_{max of} ETH and age on C_max and AUC_0-8 of CS. This is the first and only study from India reporting on the pharmacokinetics of LFX, ETH, PZA and CS in children with MDR TB treated in the Government of India programme. More studies on the safety and pharmacokinetics of second-line anti-TB drugs in children with MDR TB from different settings are required.

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Gene Expression of Pneumocystis murina after Treatment with Anidulafungin Results in Strong Signals for Sexual Reproduction, Cell Wall Integrity, and Cell Cycle Arrest, Indicating a Requirement for Asci Formation for Proliferation. [PublishAheadOfPrint]

The echinocandins are a class of anti-fungal agents that target β-1,3-D-glucan (BG) biosynthesis. In the ascigerous Pneumocystis species, treatment with these drugs deplete the asci life cycle stage which contain BG, but large numbers of forms which do not express BG remain in the infected lungs. In the present study, the gene expression profiles of Pneumocystis murina were compared between infected untreated mice and those treated with anidulafungin for 2 weeks to understand the metabolism of the persisting forms. Almost 80 genes were significantly up- or down-regulated. Like other fungi exposed to echinocandins, genes associated with sexual replication, cell wall integrity, cell cycle arrest and stress comprised the strongest up-regulated signals in P. murina from the treated mice. The up-regulation of the P. murina β-1,3-D-glucan endohydrolase and endo-1,3-glucanase was notable and may explain the disappearance of the existing asci in the lungs of treated mice since both enzymes can degrade BG. The biochemical measurement of BG in the lungs of treated mice and fluorescent microscopy with an anti-BG antibody supported the loss of BG. Down-regulated signals included genes involved in cell replication, genome stability, ribosomal biogenesis and function, and the Pneumocystis-specific genes encoding the major surface glycoproteins (Msg). These studies suggest that P. murina attempted to undergo sexual replication in response to a stressed environment and were halted in any type of proliferative cycle, likely due to a lack of BG. Asci appear to be a required part of the life cycle stage of Pneumocystis and BG may be needed to facilitate progression through the life cycle via sexual replication.

http://ift.tt/2CzxIna

A complex interplay between sphingolipid and sterol metabolism revealed by perturbations to the Leishmania metabolome caused by miltefosine [PublishAheadOfPrint]

With the World Health Organization reporting over 30,000 deaths and 200-400,000 new cases annually, visceral Leishmaniasis is a serious disease affecting some of the world's poorest people. As drug resistance continues to rise, there is a huge unmet need to improve treatment. Miltefosine remains one of the main treatments for Leishmaniasis, yet its mode of action (MoA) is still unknown. Understanding the MoA of this drug and parasite response to treatment could help pave the way for new, more successful treatments for Leishmaniasis. A novel method has been devised to study the metabolome and lipidome of Leishmania donovani axenic amastigotes treated with miltefosine. Miltefosine caused a dramatic decrease in many membrane phospholipids (PLs), in addition to amino acid pools, while sphingolipids (SLs) and sterols increased. Leishmania major promastigotes devoid of SL biosynthesis through loss of the serine palmitoyl transferase gene (LCB2) were 3-fold less sensitive to miltefosine than WT parasites. Changes in the metabolome and lipidome of miltefosine treated L. major mirrored those of L. donovani. A lack of SLs in the LCB2 was matched by substantial alterations in sterol content. Together these data indicate that SLs and ergosterol are important for miltefosine sensitivity and perhaps, MoA.

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Alginate Oligosaccharide-Induced Modification of the lasI-lasR and rhlI-rhlR Quorum Sensing Systems in Pseudomonas aeruginosa [PublishAheadOfPrint]

Pseudomonas aeruginosa plays a major role in many chronic infections. Its ability to readily form biofilms contributes to its success as an opportunistic pathogen and its resistance/tolerance to antimicrobial/antibiotic therapy. A low molecular weight alginate oligomer (OligoG CF-5/20), derived from marine algae, has previously been shown to impair motility in P. aeruginosa biofilms and disrupt pseudomonal biofilm assembly. As these bacterial phenotypes are regulated by quorum sensing (QS), we hypothesized that OligoG CF-5/20 may induce alterations in QS signalling in P. aeruginosa. QS regulation was studied using Chromobacterium violaceum CV026 biosensor assays that showed a significant reduction in acyl homoserine lactone (AHL) production following OligoG CF-5/20 treatment (≥2%; P<0.05). This effect was confirmed by liquid chromatography/mass spectrometry (LC/MS) analysis of C4-AHL and 3-oxo-C12-AHL production (≥2%; P<0.05). Moreover, quantitative PCR (qPCR) showed that reduced expression of both the las and rhl systems was induced following 24 h treatment with OligoG CF-5/20 (≥0.2%; P<0.05). Circular dichroism (CD) spectroscopy indicated that these alterations were not due to steric interaction between the AHL and OligoG CF-5/20. Confocal laser scanning microscopy and COMSTAT image analysis demonstrated that OligoG CF-5/20 treated biofilms had a dose-dependent decrease in biomass which was associated with inhibition of eDNA synthesis (≥0.5%; P<0.05). These changes correlated with alterations in extracellular production of the pseudomonal virulence factors pyocyanin, rhamnolipids, elastase and total protease (P<0.05). The ability of OligoG CF-5/20 to modify QS signalling in P. aeruginosa PAO1 which may influence critical downstream functions, such as virulence factor production and biofilm formation.

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GRL-079, a novel P2-Tp-THF-C5-alkylamine- and P2 -Abt-containing HIV-1 protease inhibitor, is extremely potent against multi-drug-resistant HIV-1 variants including HIVDRVRp51 and has a high genetic barrier against the emergence of resistant variants [PublishAheadOfPrint]

We identified four novel nonpeptidic human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs), GRL-078, -079, -077, and -058, containing an alkylamine at the C5 position of P2-tetrahydropyrano-tetrahydrofuran (Tp-THF) and a P2' -cyclopropyl (Cp)(or isopropyl)-aminobenzothiazole (Abt). Their 50% effective concentrations (EC₅₀s) were 2.5-30 nM against wild-type HIV-1_NL4-3, 0.3-6.7 nM against HIV-2_EHO, and 0.9-90 nM against laboratory-selected-PI-resistant HIV-1 and clinical HIV-1 variants resistant to multiple FDA-approved PIs (HIV_MDR). GRL-078, -079, -077, and -058 also effectively blocked the replication of HIV-1 variants highly resistant to darunavir (DRV:HIV_DRV^R_p51), with EC₅₀ values of 38, 62, 61, and 90 nM, respectively, while four FDA-approved PIs examined [amprenavir, atazanavir, lopinavir (LPV), and DRV] virtually had no activity (EC₅₀>1,000 nM) against HIV_DRV^R_p51. Structurally, GRL-078, -079, and -058 form strong hydrogen bond interactions between the C5-modified-Tp-THF and Asp29/Asp30/Gly48 of wild-type protease while P2' -Cp-Abt forms strong hydrogen bonds with Asp30' . The Tp-THF and Cp-Abt moieties also have good nonpolar interactions with protease residues located in the flap region. When selected with LPV and DRV using a mixture of 11 HIV_MDR strains (HIV_11MIX), HIV_11MIX became highly resistant to LPV and DRV over 13-32 and 32-41 weeks, respectively. However, when selected with GRL-079 and GRL-058, HIV_11MIX failed to replicate at >0.08 μM and >0.2 μM, respectively. Thermal stability results supported the highly favorable anti-HIV-1 potency of GRL-079 as well as other PIs. The present data strongly suggest that the C5-modified P2-Tp-THF and P2' -Abt moiety contribute to the potent anti-HIV-1 profiles of the four PIs against HIV-1_NL4-3 and a wide spectrum of HIV_MDRs.

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Pharmacokinetics of penicillin G in preterm and term neonates [PublishAheadOfPrint]

Group B streptococci are common causative agents of early-onset neonatal sepsis (EOS). Pharmacokinetic (PK) data for penicillin G have been described for extremely preterm neonates but poorly for late-preterm and term neonates. Thus, evidence-based dosing recommendations are lacking. We described PK of penicillin G in neonates with gestational age (GA) ≥32 weeks and postnatal age <72 h. Penicillin G was administered intravenously at a dose of 25,000 or 50,000 IU/kg/q12h. At steady state, PK blood samples were collected prior to and at 5 min, 1 h, 3 h, 8 h, 12 h after injection. Non-compartmental PK analysis was performed with WinNonlin. In combination with data from neonates with GA ≤28 weeks we developed a population PK model using NONMEM software and performed probability of target attainment (PTA) simulations. In total, 16 neonates with GA ≥32 weeks were included in non-compartmental analysis. The median (interquartile range) volume of distribution (VD) was 0.50 (0.42-0.57) L/kg, clearance (CL) 0.21 (0.16-0.29) L/h and half-life 3.6 (3.2-4.3) h. In population PK analysis that included 35 neonates, a two-compartment model best described the data. The final parameter estimates were 10.3 L/70kg and 29.8 L/70kg for VD of the central and peripheral compartment, respectively, and 13.2 L/h/70kg for CL. Considering fraction of unbound penicillin G of 40%, PTA of time when the unbound drug exceeds MIC of 40% was >90% for MICs ≤2 mg/L with doses of 25,000 IU/kg/q12h. In neonates, regardless of GA, PK parameters of penicillin G are similar. The dose of 25,000 IU/kg/q12h is suggested for treatment of group B streptococcal EOS diagnosed within the first 72 hours of life.

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Verapamil targets membrane energetics in Mycobacterium tuberculosis [PublishAheadOfPrint]

Mycobacterium tuberculosis (Mtb) kills more people than any other bacterial pathogen and is becoming increasingly untreatable due to the emergence of resistance. Verapamil, an FDA-approved calcium channel blocker, potentiates the effect of several anti-tuberculosis (TB) drugs in vitro and in vivo. This potentiation is widely attributed to inhibition of Mtb's efflux pumps, resulting in intrabacterial drug accumulation. Here, we confirm and quantify verapamil's synergy with several anti-TB drugs, including bedaquiline and clofazimine, but find that this effect is not due to increased intrabacterial drug accumulation. Consistent with its in vitro potentiating effects on TB drugs that target or require oxidative phosphorylation, we show that the cationic amphiphile verapamil disrupts membrane function and induces a membrane stress response, similar to other membrane-active agents. We recapitulate these activities in vitro using inverted mycobacterial membrane vesicles, indicating a direct effect of verapamil on membrane energetics. Consistent with such mechanism of action, we observe bactericidal activity against non-replicating 'persister' Mtb. In addition, we demonstrate a pharmacokinetic interaction whereby human-equivalent doses of verapamil cause a boost of rifampicin exposure in mice, providing a potential explanation for the observed treatment shortening effect of verapamil in mice receiving first line drugs. Our findings thus elucidate the mechanistic basis for verapamil's potentiation of TB drugs in vitro and in vivo, and highlight a previously unrecognized role for Mtb's membrane as pharmacologic target.

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Detection of TR34/L98H Cyp51A mutation through passive surveillance for azole-resistant Aspergillus fumigatus in the US, 2015-2017 [PublishAheadOfPrint]

Emergence of azole resistant Aspergillus fumigatus has become a clinical problem in many parts of the world. Several amino acid mutations in the azole target protein, Cyp51Ap, contribute to this resistance, with the most concerning being the environmentally-derived TR₃₄/L98H and TR₄₆/Y121F/T289A mutations. Here, we performed passive surveillance to assess a sample of the A. fumigatus population in the US for the presence of these mutations. We found 1.4% of those isolates to exhibit elevated MIC via broth microdilution and five of those isolates harbored the TR₃₄/L98H mutation.

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Impact of oral fidaxomicin administration on the intestinal microbiota and susceptibility to Clostridium difficile colonization in mice [PublishAheadOfPrint]

Clostridium difficile infection (CDI), a common cause of hospital-acquired infections, typically occurs after disruption of the normal gut microbiome by broad-spectrum antibiotics. Fidaxomicin is a narrow-spectrum antibiotic that demonstrates reduced impact on the normal gut microbiota and is approved for the treatment of CDI. To further explore the benefits of this property, we used a murine model to examine the effects of fidaxomicin versus vancomycin on gut microbiota and susceptibility to C. difficile colonization while tracking microbiota recovery over time.

Mice were exposed to fidaxomicin or vancomycin by oral gavage for 3 days, and subsequently challenged with C. difficile spores at predetermined time points up to 21 days post-antibiotic exposure. Fecal samples were subsequently collected for analysis. Twenty-four hours post-challenge, mice were euthanized and colon contents harvested. The microbiota was characterized using 16S rDNA gene sequencing.

All fidaxomicin exposed mice (except for one at Day 8) were resistant to C. difficile colonization. However, 9 of 15 vancomycin exposed mice were susceptible to C. difficile colonization until Day 12. All vancomycin exposed mice recovered colonization resistance by Day 16. Bacterial diversity was similar prior to antibiotic exposure in both arms and decreased substantially after exposure. A shift in taxonomic structure and composition occurred after both exposures; however, the shift was greater in vancomycin- than in fidaxomicin-exposed mice.

In summary, compared with vancomycin, fidaxomicin exposure had less impact on microbiota composition, promoted faster microbial recovery and had less impact on loss of C. difficile colonization resistance.

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Mesoscopic Energy Minimization Drives Pseudomonas aeruginosa Biofilm Morphologies and Consequent Stratification of Antibiotic Activity Based on Cell Metabolism [PublishAheadOfPrint]

Segregation of bacteria based on their metabolic activity in biofilms plays an important role in the development of antibiotic drug resistance. Mushroom-shaped biofilm structures, which are reported for many bacteria, exhibit topographically varying levels of multiple drug resistance from the cap of the mushroom to its stalk. Understanding the dynamics behind the formation of such structures can aid in design of drug delivery systems, antibiotics, or physical systems for removal of biofilms. We explore the development of metabolically heterogenous Pseudomonas aeruginosa biofilms using numerical models and laboratory knock-out experiments on wild-type and chemotaxis deficient mutants. We show that chemotactic processes dominate the transformation of slender and hemispherical structures into mushroom structures with a signature cap. Cellular Potts model simulation and experimental data provide evidence that accelerated movement of bacteria along the periphery of the biofilm, due to nutrient cues, results in the formation of mushroom structures and bacterial segregation. Multi-drug resistance of bacteria is one of the most threatening dangers to public health. Understanding the mechanisms of the development of mushroom shaped biofilms helps to identify the multidrug resistant regions. We decoded the dynamics of the structural evolution of bacterial biofilms and the physics behind the formation of biofilm structures as well as the biological triggers that produce them. Combining in-vitro gene knock-out experiments with in-silico models shows that chemotactic motility is one of the main driving forces for the formation of stalks and caps. Our result provides physicists and biologists with a new perspective on biofilm removal and eradication strategies.

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Promoter variation and gene expression of mcr-1-harboring plasmids in clinical isolates of Escherichia coli and Klebsiella pneumoniae from a Chinese hospital [PublishAheadOfPrint]

Next generation sequencing of six mcr-1-harboring Escherichia coli and Klebsiella pneumoniae isolates collected from a tertiary care hospital in China revealed significant sequence variations in the regions flanking the mcr-1 gene. While sequence variations significantly affect the expression and promoter activity of mcr-1, the mcr-1 gene expressions do not correlate with the in vitro colistin resistance levels, which warrants further in-depth investigations.

http://ift.tt/2EKFYqk

Population Pharmacokinetic properties of Sulfadoxine and Pyrimethamine: A pooled analysis to Inform Optimal Dosing in African Children with Uncomplicated Malaria. [PublishAheadOfPrint]

Sulfadoxine/pyrimethamine with amodiaquine is recommended by the World Health Organization as seasonal malaria chemoprevention for children between 3 to 59 months in the sub-Sahel regions of Africa. Sub-optimal dosing in children may lead to treatment failure and increased resistance. Pooled individual patient data from four previously published trials on the pharmacokinetics of sulfadoxine and pyrimethamine in 415 paediatric and 386 adult patients were analysed using nonlinear mixed effects modelling to evaluate the current dosing regimen and, if needed, propose an optimised dosing regimen in children under five years old. The population pharmacokinetics of sulfadoxine and pyrimethamine were both best described by a one-compartment disposition model, with first-order absorption and elimination. Body weight, age and nutrition status (measured as weight-for-age z-scores) were found to be significant covariates. Allometric scaling with total body weight and maturation of clearance in children using post-gestational age improved the model fit. Underweight-for-age children were found to have 15.3% and 26.7% lower bioavailability of sulfadoxine and pyrimethamine, respectively, for each z-score unit below minus 2. Under current dosing recommendations, simulation predicted that the median day 7 concentration was below the 25^th percentile of a typical adult patient (50 kg) for sulfadoxine for patients in 8-9, 19-24, 46-49 and 74-79 kg weight bands, and for pyrimethamine for the weight-bands 8-9, 14-24 and 42-49 kg. An evidence-based dosing regimen was constructed that would achieve sulfadoxine and pyrimethamine exposure in young children and underweight-for-age young children that was similar to that currently seen in a typical adult.

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Treatment with atorvastatin provides additional benefits to imipenem in a model of Gram-negative pneumonia induced by Klebsiella pneumoniae in mice [PublishAheadOfPrint]

The clinical pathogen Klebsiella pneumoniae is a relevant cause of nosocomial infections and resistance to current treatment with carbapenem antibiotics is becoming a significant problem. Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) used for controlling plasma cholesterol levels. There is clinical evidence showing other effects of statins, including decrease of lung inflammation. In the current study, we show that pretreatment with atorvastatin markedly attenuated lung injury, which was correlated with a reduction in the cellular influx into the alveolar space and lungs and down-modulation of the production of pro-inflammatory mediators in the initial phase of infection in C57BL/6 mice with K. pneumoniae. However, atorvastatin did not alter the number of bacteria in the lungs and blood of infected mice, despite decreasing local inflammatory response. Interestingly, mice that received combined treatment with atorvastatin and imipenem displayed better survival rate than mice treated with vehicle, atorvastatin or imipenem alone. These findings suggest that atorvastatin could be an adjuvant in host-directed therapies for multidrug-resistant K. pneumoniae, based on its powerful pleiotropic immunomodulatory effects. Together with antimicrobial approaches, combination therapy with anti-inflammatory compounds could improve the efficiency of therapy during acute lung infections.

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Relationship between tolerance and persistence mechanisms in Acinetobacter baumannii strains with AbkAB Toxin-Antitoxin system [PublishAheadOfPrint]

Unknown are the mechanisms of tolerance and persistence associated to several compounds in A.baumannii clinical isolates. Using transcriptomic and microbiological studies, we found a link between bacterial tolerance mechanisms to clorhexidine as well as the development of persistence in presence of imipenem in A.baumannii strain belonging to ST-2 clinical clone (OXA-24 ß-lactamase and AbkAB TA system by plasmid). Interestingly, A.baumannii ATCC17978 strain (AbkAB TA system by plasmid) showed persistence in presence of imipenem and chlorhexidine.

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Optimization and evaluation of piperacillin plus tobramycin combination dosage regimens against Pseudomonas aeruginosa for patients with altered pharmacokinetics via the hollow-fiber infection model and mechanism-based modeling [PublishAheadOfPrint]

Augmented renal clearance (ARC) in critically-ill patients can result in suboptimal drug exposures and treatment failure. Combination dosage regimens accounting for ARC have never been optimized and evaluated against Pseudomonas aeruginosa using the hollow-fiber infection model (HFIM). Using a P. aeruginosa isolate from a critically-ill patient and static concentration time-kill experiments (SCTK), we studied clinically relevant piperacillin and tobramycin concentrations, alone and in combinations, at two inocula (10^5.8 and 10^7.6 CFU/mL) over 72h. We subsequently evaluated the effect of optimized piperacillin (4 g q4h, 0.5h infusion) plus tobramycin (5 mg/kg q24h, 7 mg/kg q24h and 10 mg/kg q48h as 0.5h infusions) regimens on killing and regrowth in the HFIM, simulating a creatinine clearance of 250 mL/min. Mechanism-based modeling was performed in S-ADAPT. In SCTKs, piperacillin plus tobramycin (except combinations with 8 mg/liter tobramycin at low inoculum) achieved synergistic killing (≥2 log₁₀vs. the most active monotherapy at 48h and 72h) and prevented regrowth. Piperacillin monotherapy (4 g q4h) in the HFIM provided 2.4 log₁₀ initial killing followed by regrowth at 24h with resistance emergence. Tobramycin monotherapies displayed rapid initial killing (≥5 log₁₀ at 13h) followed by extensive regrowth. As predicted by mechanism-based modeling, the piperacillin plus tobramycin dosage regimens were synergistic and provided ≥5 log₁₀ killing with resistance suppression over 8 days in the HFIM. Optimized piperacillin plus tobramycin regimens provided significant bacterial killing and suppressed resistance emergence. These regimens appear highly promising for effective and early treatment, even in the near-worst case scenario of ARC.

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Kelch mutations in Plasmodium falciparum protein K13 do not modulate dormancy after artemisinin exposure and sorbitol selection in vitro [PublishAheadOfPrint]

Some Kelch mutations of Plasmodium falciparum K13 protein confer increased survival to dihydroartemisinin (DHA)-treated ring-stage parasites. Here, we ask if K13 mutations affect a dormancy phenotype allowing parasites to survive DHA exposure then sorbitol selection. Although recrudescence from dormancy differed between two distinct parasites lines, it was similar for isogenic lines carrying single-site substitutions in K13. Therefore, K13 mutations do not alter the DHA-sorbitol combined dormancy phenotype; traits from other loci likely determine this phenotype.

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Complete genome sequencing of Acinetobacter baumannii str. K50 disclosed the large conjugative plasmid pK50a encoding the carbapenemase OXA-23 and the extended-spectrum {beta}-lactamase GES-11 [PublishAheadOfPrint]

Multidrug-resistant (MDR) Acinetobacter baumannii strains appeared as serious emerging nosocomial pathogens in clinical environments and especially in intensive care units (ICUs). A. baumannii strain K50 recovered from a hospitalized patient in Kuwait exhibited resistance to carbapenems, and additionally to ciprofloxacin, chloramphenicol, sulfonamides, amikacin and gentamicin. Genome sequencing revealed that the strain possesses two plasmids, pK50a (79.6 kb) and pK50b (9.5 kb) and a 3.75 Mb chromosome. A. baumannii K50 exhibits an Average Nucleotide Identity (ANI) value of 99.98% to the previously reported Iraqi clinical isolate AA-014, even though that the latter strain lacked plasmid pK50a. Strain K50 belongs to the Sequence Type ST158 (Pasteur scheme) and ST499 according to the Oxford scheme. Plasmid pK50a is a member of the Aci6 (RG6) group of Acinetobacter plasmids, and encodes a conjugative transfer module and two antibiotic resistance gene regions comprising the transposon Tn2008. The transposon carries the carbapenemase gene bla_OXA-23 and a class 1 integron harboring the resistance genes bla_GES-11, aacA4, dfrA7, qacE1 and sul1 conferring resistance to all β-lactams and reduced susceptibility to carbapenems, resistance to aminoglycosides, trimethoprim, quaternary ammonium compounds and sulfamethoxazole, respectively. The class 1 integron is flanked by MITEs (Miniature Inverted repeat Transposable Element) delimiting the element at its insertion site.

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A new marker of echinocandins activity in an in vitro PK/PD model correlates with an animal model of Aspergillus fumigatus infection [PublishAheadOfPrint]

The lack of a quantifiable marker for echinocandins activity hinders in vitro PK/PD studies for Aspergillus spp. We developed an in vitro PK/PD model simulating anidulafungin pharmacokinetics and assessing its pharmacodynamics against A. fumigatus with a new easily quantifiable, sensitive and reproducible marker. Two clinical A. fumigatus isolates previously used in animals (AZN8196,V52-35) with identical anidulafungin EUCAST (0.03 μg/ml) and CLSI (0.015 μg/ml) MEC and one (AFU79728) with MEC>16 μg/ml were tested in a two-compartment PK/PD dialysis/diffusion closed model containing a dialysis membrane tube (DM) inoculated with 10³ cfu/mL. During anidulafungin exposure, two types of fungal forms were observed inside the DM, floating conidia that were quantified by cultures and attached aberrant mycelia that were quantified by the vertical height of the mycelia covering the DM. No aberrant mycelia were found for the resistant isolate and in the drug-free controls. In vitro exposure-effect relationship was similar with that found in animals using survival as an endpoint with fAUC_0-24 (range) associated with 50% of maximal activity of 2.21 (1.81-2.71) vs 2.62 (1.88-3.65) (p=0.41), respectively. The Hillslopes were also similar, 1.96 vs 1.34 (p=0.29). Analysis of each isolate separately showed increased antifungal susceptibility between AZN8196 and V52-35 (p<0.001) despite the same CLSI and EUCAST MECs but 2 two-fold lower MICs using Etest and XTT method. Dose fractionation studies with all three echinocandins showed that their activity is best described by fAUC rather than fC_max. The new marker correlated with in vivo outcome and can be used for in vitro PK/PD studies exploring pharmacodynamics of echinocandins against Aspergillus spp.

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PGI2, a novel SGI1-relative multidrug-resistant genomic island characterized in Proteus mirabilis [PublishAheadOfPrint]

A novel 61,578 bp genomic island named Proteus genomic island 2 (PGI2) was characterized in P. mirabilis of swine origin in China. The 23.85-kb backbone of PGI2 is related to that of Salmonella genomic island 1 and Acinetobacter genomic island 1. The MDR region of PGI2 is a complex class 1 integron containing fourteen different resistance genes. PGI2 was conjugally mobilized in trans to Escherichia coli in the presence of a conjugative IncC helper plasmid.

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Elevated Plasma Moxifloxacin Concentrations and SLCO1B1 g.-11187G>A Polymorphism in Adults with Pulmonary Tuberculosis [PublishAheadOfPrint]

Moxifloxacin exhibits concentration-dependent prolongation of human QTc intervals and bactericidal activity against Mycobacterium tuberculosis. However, moxifloxacin plasma concentrations are variable between patients. We evaluated whether human gene polymorphisms affect moxifloxacin plasma concentrations in tuberculosis patients from two geographic regions. We enrolled a convenience sample of 49 adults with drug-sensitive pulmonary tuberculosis from Africa and the United State s enrolled in two treatment trials of moxifloxacin as part of multidrug therapy. Pharmacokinetic parameters were evaluated by noncompartmental techniques. Human single-nucleotide polymorphisms of transporter genes were evaluated with analysis of covariance on moxifloxacin exposure and peak concentration (C_max). Moxifloxacin area under the concentration-time curve from 0 to 24 h (AUC_0-24) and C_max were significantly increased by drug mg/kg dosage and genotype of variant g.-11187G>A in the SLCO1B1 gene (rs4149015), but not by geographic region. Median moxifloxacin AUC_0-24 was 46% higher and C_max 30% higher in 4 (8% of) participants who had the SLCO1B1 g.-11187 AG genotype compared with 45 participants who had the wild type GG genotype (median from model, AUC_0-24 34.4 vs. 23.6 μg*h/mL, P =.005; C_max 3.5 vs. 2.7 μg/mL, P =.009, ANCOVA). Because moxifloxacin exhibits concentration-dependent prolongation of human QTc intervals, and prolonged QTc intervals are associated with cardiac arrhythmia, further study is needed to evaluate risk associated with the SLCO1B1 g.-11187G>A variant.

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Speech Intelligibility Predicted from Neural Entrainment of the Speech Envelope

Abstract

Speech intelligibility is currently measured by scoring how well a person can identify a speech signal. The results of such behavioral measures reflect neural processing of the speech signal, but are also influenced by language processing, motivation, and memory. Very often, electrophysiological measures of hearing give insight in the neural processing of sound. However, in most methods, non-speech stimuli are used, making it hard to relate the results to behavioral measures of speech intelligibility. The use of natural running speech as a stimulus in electrophysiological measures of hearing is a paradigm shift which allows to bridge the gap between behavioral and electrophysiological measures. Here, by decoding the speech envelope from the electroencephalogram, and correlating it with the stimulus envelope, we demonstrate an electrophysiological measure of neural processing of running speech. We show that behaviorally measured speech intelligibility is strongly correlated with our electrophysiological measure. Our results pave the way towards an objective and automatic way of assessing neural processing of speech presented through auditory prostheses, reducing confounds such as attention and cognitive capabilities. We anticipate that our electrophysiological measure will allow better differential diagnosis of the auditory system, and will allow the development of closed-loop auditory prostheses that automatically adapt to individual users.

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Optimal Human Passive Vestibulo-Ocular Reflex Adaptation Does Not Rely on Passive Training

Abstract

The vestibulo-ocular reflex (VOR) is the main vision-stabilising system during rapid head movements in humans. A visual-vestibular mismatch stimulus can be used to train or adapt the VOR response because it induces a retinal image slip error signal that drives VOR motor learning. The training context has been shown to affect VOR adaptation. We sought to determine whether active (self-generated) versus passive (externally imposed) head rotation vestibular training would differentially affect adaptation and short-term retention of the active and passive VOR responses. Ten subjects were tested, each over six separate 1.5-h sessions. We compared active versus passive head impulse (transient, rapid head rotations with peak velocity ~ 150 °/s) VOR adaptation training lasting 15 min with the VOR gain challenged to increment, starting at unity, by 0.1 every 90 s towards one side only (this adapting side was randomised to be either left or right). The VOR response was tested/measured in darkness at 10-min intervals, 20-min intervals, and two single 60-min interval sessions for 1 h post-training. The training was active or passive for the 10- and 20-min interval sessions, but only active for the two single 60-min interval sessions. The mean VOR response increase due to training was ~ 10 % towards the adapting side versus ~2 % towards the non-adapting side. There was no difference in VOR adaptation and retention between active and passive VOR training. The only factor to affect retention was exposure to a de-adaptation stimulus. These data suggest that active VOR adaptation training can be used to optimally adapt the passive VOR and that adaptation is completely retained over 1 h as long as there is no visual feedback signal driving de-adaptation.

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Hochauflösungsmanometrische Evaluation des velopharyngealen Verschlussdrucks beim Trompetenspiel

Laryngo-Rhino-Otol
DOI: 10.1055/s-0043-124971

Hintergrund Bei etwa einem Drittel der Blasmusiker kommt es zu belastungsbedingten Insuffizienzen des velopharyngealen Abschlusses (VPA), d. h. der intraorale Druck übersteigt die durch den VPA gebildete Barriere. In dieser Studie sollte der Verschlussdruck im VPA beim Spielen einer Trompete gemessen und über prüft werden, welchen Einfluss eine 30-minütige Belastungssequenz auf die muskulären Aktivitäten im VPA hat. Material und Methoden Stichprobe: 6 gesunde Probanden. Aufgabe: Spielen des Tons h1 über 5 Sekunden mit 85 dB(A) und mit 100 dB(A). Methodik: Hochauflösungsmanometrie (HRM); Messzeitpunkte: t0: Messung ohne Einspielphase, t1 nach 30 min Trompetenspiel mit vorgegebenen Musikstücken. Variablen: mittlere Drücke (pmit), Minimal-(pmin)- sowie Maximaldrücke (pmax) zu t0 und t1 im VPA. Statistik: Prüfung auf Normalverteilung, t-test. Ergebnisse Alle gemessenen Drücke im VPA sanken von t0 zu t1 für produzierte 85 dB(A) Töne. Für 100 dB(A) Töne sanken nur die pmin. Die Drücke im VPA waren bei 100 dB(A) Tönen insgesamt höher als bei 85 dB(A) Tönen, signifikant war dieser Unterschied nur für pmin und pmax zu t0. Schlussfolgerung Lauter gespielte Töne erfordern eine stärkere muskuläre Kontraktion im VPA. Der niedrigere Verschlussdruck im VPA zum Zeitpunkt t1 kann Folge einer physiologischen muskulären Adaptation an das für den VPA notwendige Druckniveau oder bereits Zeichen einer muskulären Ermüdung sein. Dies ist möglicherweise für den Einsatz der HRM zur Beurteilung der Berufsfähigkeit von Blasinstrumentalisten von Bedeutung. Wie schon für die Phonation beschrieben, ließ sich auch hier mit einem dreiphasigen Modell, bestehend aus Initiation, stabiler Phase und Terminierung, der VPA Druckverlauf beschreiben.
[...]

© Georg Thieme Verlag KG Stuttgart · New York

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Small, Smart Technology Opens a World of Sound for Kaci Mueller

Between the 4th and 8th grades, Kaci Mueller suffered repeated ear infections and underwent more than 10 surgeries for cholesteatoma,... Read the full article...

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Citardi and Luong Named to Best Doctors List for Otorhinolaryngology

Two of the nation's top otorhinolaryngologists practice at UT Physicians, the clinical practice of McGovern Medical School at The University... Read the full article...

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UT Physicians Otolaryngology at Texas Medical Center Clinic Redesign Improves the Patient Experience

With a 50 percent increase in faculty in the Department of Otorhinolaryngology-Head & Neck Surgery at McGovern Medical School at... Read the full article...

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Inflammation-Sensitive Myosin-X Functionally Supports Leukocyte Extravasation by Cdc42-Mediated ICAM-1-Rich Endothelial Filopodia Formation [INNATE IMMUNITY AND INFLAMMATION]

Leukocyte transendothelial migration is key to inflammation. Leukocytes first start rolling over the inflamed endothelium, followed by firmly adhering to it. Under inflammatory conditions, endothelial cells express small finger-like protrusions that stick out into the lumen. The function and regulation of these structures are unclear. We present evidence that these ICAM-1– and F-actin–rich endothelial finger-like protrusions are filopodia and function as adhesive structures for leukocytes to transit from rolling to crawling but are dispensable for diapedesis. Mechanistically, these structures require the motor function of myosin-X, activity of the small GTPase Cdc42, and p21-activated kinase 4. Moreover, myosin-X expression is under control of TNF-α–mediated c-Jun N-terminal kinase activity and is upregulated in human atherosclerotic regions. To our knowledge, this is the first study to identify that regulation of endothelial filopodia is crucial for leukocyte extravasation, in particular for the initiation of leukocyte adhesion under flow conditions.

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CD11b+ Dendritic Cell-Mediated Anti-Mycobacterium tuberculosis Th1 Activation Is Counterregulated by CD103+ Dendritic Cells via IL-10 [INFECTIOUS DISEASE AND HOST RESPONSE]

Mycobacterium tuberculosis, the pathogen causing pulmonary tuberculosis (TB) in humans, has evolved to delay Th1 immunity in the lung. Although conventional dendritic cells (cDCs) are known to be critical to the initiation of T cell immunity, the differential roles and molecular mechanisms of migratory CD11b⁺ and CD103⁺ cDC subsets in anti–M. tuberculosis Th1 activation remain unclear. Using a murine model of pulmonary M. tuberculosis infection, we found that slow arrival of M. tuberculosis–bearing migratory CD11b⁺ and CD103⁺ cDCs at the draining lymph nodes preceded the much-delayed Th1 immunity and protection in the lung. Contrary to their previously described general roles in Th polarization, CD11b⁺ cDCs, but not CD103⁺ cDCs, were critically required for Th1 activation in draining lymph nodes following M. tuberculosis infection. CD103⁺ cDCs counterregulated CD11b⁺ cDC–mediated Th1 activation directly by producing the immune-suppressive cytokine IL-10. Thus, our study provides new mechanistic insights into differential Th immune regulation by migratory cDC subsets and helps to develop novel vaccines and therapies.

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The Chemical Elucidation of Slow-Reacting Substance: Bronchospasm and Beyond [PILLARS OF IMMUNOLOGY]

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Alveolar Macrophages Drive Hepatocellular Carcinoma Lung Metastasis by Generating Leukotriene B4 [INNATE IMMUNITY AND INFLAMMATION]

Macrophages in lungs can be classified into two subpopulations, alveolar macrophages (AMs) and interstitial macrophages (IMs), which reside in the alveolar and interstitial spaces, respectively. Accumulating evidence indicates the involvement of IMs in lung metastasis, but the roles of AMs in lung metastasis still remain elusive. An i.v. injection of a mouse hepatocellular carcinoma (HCC) cell line, BNL, caused lung metastasis foci with infiltration of AMs and IMs. Comprehensive determination of arachidonic acid metabolite levels revealed increases in leukotrienes and PGs in lungs in this metastasis model. A 5-lipoxygenase (LOX) inhibitor but not a cyclooxygenase inhibitor reduced the numbers of metastatic foci, particularly those of a larger size. A major 5-LOX metabolite, LTB₄, augmented in vitro cell proliferation of human HCC cell lines as well as BNL cells. Moreover, in this lung metastasis course, AMs exhibited higher expression levels of the 5-LOX and LTB₄ than IMs. Consistently, 5-LOX–expressing AMs increased in the lungs of human HCC patients with lung metastasis, compared with those without lung metastasis. Furthermore, intratracheal clodronate liposome injection selectively depleted AMs but not IMs, together with reduced LTB₄ content and metastatic foci numbers in this lung metastasis process. Finally, IMs in mouse metastatic foci produced CCL2, thereby recruiting blood-borne, CCR2–expressing AMs into lungs. Thus, AMs can be recruited under the guidance of IM-derived CCL2 into metastatic lungs and can eventually contribute to the progression of lung metastasis by providing a potent arachidonic acid–derived tumor growth promoting mediator, LTB₄.

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Intracellular BH3 Profiling Reveals Shifts in Antiapoptotic Dependency in Human B Cell Maturation and Mitogen-Stimulated Proliferation [INFECTIOUS DISEASE AND HOST RESPONSE]

Apoptosis is critical to B cell maturation, but studies of apoptotic regulation in primary human B cells is lacking. In this study, we sought to better understand the mechanisms of apoptotic regulation in normal and activated B cells. Using intracellular BH3 profiling, we defined the Bcl2 dependency of B cell subsets from human peripheral blood and tonsillar lymphoid tissue as well as mitogen-activated B cells. We found that naive and memory B cells were BCL-2–dependent, whereas germinal center B cells were MCL-1–dependent and plasma cells were BCL-X_L–dependent. B cells stimulated to proliferate ex vivo by CpG or CD40L/IL-4 became more dependent on MCL-1 and BCL-X_L. As B cell lymphomas often rely on survival mechanisms derived from normal and activated B cells, these findings offer new insight into potential therapeutic strategies for lymphomas.

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Antagonism of Integrin CD11b Affords Protection against Endotoxin Shock and Polymicrobial Sepsis via Attenuation of HMGB1 Nucleocytoplasmic Translocation and Extracellular Release [INNATE IMMUNITY AND INFLAMMATION]

High mobility group box 1 (HMGB1), a chromatin-binding nuclear protein, plays a critical role in sepsis by acting as a key "late-phase" inflammatory mediator. Integrin CD11b is essential for inflammatory cell activation and migration, thus mediating inflammatory responses. However, it is unclear whether CD11b participates in the development of sepsis. In this study, we report that CD11b contributes to LPS-induced endotoxin shock and microbial sepsis, as antagonism of CD11b with the CD11b blocking Ab or CD11b inhibitor Gu-4 protects mice against LPS- and microbial sepsis-related lethality, which is associated with significantly diminished serum HMGB1 levels. Consistent with this, CD11b-deficient mice were more resistant to microbial sepsis with a much lower serum HMGB1 level compared with wild-type mice. Pharmacological blockage and genetic knockdown/knockout of CD11b in murine macrophages hampered LPS-stimulated HMGB1 nucleocytoplasmic translocation and extracellular release. Furthermore, silencing CD11b interrupted the interaction of HMGB1 with either a nuclear export factor chromosome region maintenance 1 or classical protein kinase C and inhibited classical protein kinase C–induced HMGB1 phosphorylation, the potential underlying mechanism(s) responsible for CD11b blockage-induced suppression of HMGB1 nucleocytoplasmic translocation and subsequent extracellular release. Thus, our results highlight that CD11b contributes to the development of sepsis, predominantly by facilitating nucleocytoplasmic translocation and active release of HMGB1.

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PAD4 Deficiency Leads to Decreased Organ Dysfunction and Improved Survival in a Dual Insult Model of Hemorrhagic Shock and Sepsis [INNATE IMMUNITY AND INFLAMMATION]

Indirect acute respiratory distress syndrome (iARDS) is caused by a nonpulmonary inflammatory process resulting from insults such as nonpulmonary sepsis. Neutrophils are thought to play a significant role in mediating ARDS, with the development of iARDS being characterized by dysregulation and recruitment of activated neutrophils into the lung. Recently, a novel mechanism of microbial killing by neutrophils was identified through the formation of neutrophil extracellular traps (NETs). NETs are composed of large webs of decondensed chromatin released from activated neutrophils into the extracellular space; they are regulated by the enzyme peptidylarginine deiminase 4 (PAD4) through mediation of chromatin decondensation via citrullination of target histones. Components of NETs have been implicated in ARDS. However, it is unknown whether there is any pathological significance of NET formation in ARDS caused indirectly by nonpulmonary insult. We subjected PAD4^–/– mice and wild-type mice to a "two-hit" model of hypovolemic shock (fixed-pressure hemorrhage [Hem]) followed by septic cecal ligation and puncture (CLP) insult (Hem/CLP). Mice were hemorrhaged and resuscitated; 24 h after Hem, mice were then subjected to CLP. Overall, PAD4 deletion led to an improved survival as compared with wild-type mice. PAD4^–/– mice displayed a marked decrease in neutrophil influx into the lung, as well decreased presence of proinflammatory mediators. PAD4^–/– mice were also able to maintain baseline kidney function after Hem/CLP. These data taken together suggest PAD4-mediated NET formation contributes to the mortality associated with shock/sepsis and may play a role in the pathobiology of end organ injury in response to combined hemorrhage plus sepsis.

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Locus-Specific Reversible DNA Methylation Regulates Transient IL-10 Expression in Th1 Cells [MOLECULAR AND STRUCTURAL IMMUNOLOGY]

IL-10 is a pleiotropic cytokine with multifaceted functions in establishing immune homeostasis. Although expressed by Th1 and Th2 cells, conventional Th1 cells produce marginal levels of IL-10 compared with their Th2 counterparts. In this study, we investigated the epigenetic mechanisms of Il-10 gene expression in Th1 cells. Bioinformatics EMBOSS CpG plot analysis and bisulfite pyrosequencing revealed three CpG DNA methylation sites in the Il-10 gene locus. Progressive DNA methylation at all of the CpG regions of interest (ROIs) established a repressive program of Il-10 gene expression in Th1 cells. Interestingly, Th1 cells treated with IL-12 and IL-27 cytokines, thereby mimicking a chronic inflammatory condition in vivo, displayed a significant increase in IL-10 production that was accompanied by selective DNA demethylation at ROI 3 located in intron 3. IL-10–producing T cells isolated from lymphocytic choriomeningitis virus–infected mice also showed enhanced DNA demethylation at ROI 3. Binding of STAT1 and STAT3 to demethylated ROI 3 enhanced IL-10 expression in an IL-12/IL-27–dependent manner. Accordingly, CD4⁺ T cells isolated from STAT1- or STAT3-knockout mice were significantly defective in IL-10 production. Our data suggest that, although stably maintained DNA methylation at the promoter may repress IL-10 expression in Th1 cells, locus-specific reversible DNA demethylation may serve as a threshold platform to control transient Il-10 gene expression.

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Just do the right thing

Early in my training as an allergy-immunology fellow at Wilford Hall Medical Center, I had a patient in which more than one therapeutic approach might apply. I could not decide which pathway to choose and sought the advice of Mike Ruff, a physician on staff. He simply said, "Ted, just do the right thing." This advice has been valuable to me over the years.

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Correction: Definition of the Nature and Hapten Threshold of the {beta}-Lactam Antigen Required for T Cell Activation In Vitro and in Patients [CORRECTIONS]

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Correction: The Effect of Inhibitory Signals on the Priming of Drug Hapten-Specific T Cells That Express Distinct V{beta} Receptors [CORRECTIONS]

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Detection of Experimental and Clinical Immune Complexes by Measuring SHIP-1 Recruitment to the Inhibitory Fc{gamma}RIIB [NOVEL IMMUNOLOGICAL METHODS]

Fc receptors (FcR) are involved in multiple aspects of immune cell regulation, are central to the success of mAb therapeutics, and underpin the pathology of several autoimmune diseases. However, reliable assays capable of accurately measuring FcR interactions with their physiological ligands, IgG immune complexes (IC), are limited. A method to study and detect IC interactions with FcRs was therefore developed. This method, designed to model the signaling pathway of the inhibitory FcRIIB (CD32B), used NanoLuc Binary Interaction Technology to measure recruitment of the Src homology 2 domain–containing inositol phosphatase 1 to the ITIM of this receptor. Such recruitment required prior cross-linking of an ITAM-containing activatory receptor, and evoked luciferase activity in discrete clusters at the cell surface, recapitulating the known biology of CD32B signaling. The assay detected varying forms of experimental IC, including heat-aggregated IgG, rituximab–anti-idiotype complexes, and anti-trinitrophenol–trinitrophenol complexes in a sensitive manner (≤1 μg/ml), and discriminated between complexes of varying size and isotype. Proof-of-concept for the detection of circulating ICs in autoimmune disease was provided, as responses to sera from patients with systemic lupus erythematosus and rheumatoid arthritis were detected in small pilot studies. Finally, the method was translated to a stable cell line system. In conclusion, a rapid and robust method for the detection of IC was developed, which has numerous potential applications including the monitoring of IC in autoimmune diseases and the study of underlying FcR biology.

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KEAP1 Editing Using CRISPR/Cas9 for Therapeutic NRF2 Activation in Primary Human T Lymphocytes [NOVEL IMMUNOLOGICAL METHODS]

Oxidant stress modifies T lymphocyte activation and function. Previous work demonstrated that murine T cell–specific kelch like-ECH-associated protein 1 (Keap1) deletion enhances antioxidant capacity and protects from experimental acute kidney injury. In this study, we used CRISPR technology to develop clinically translatable human T cell–specific KEAP1 deletion. Delivery of KEAP1 exon 2 specific Cas9:guide RNA in Jurkat T cells led to significant (~70%) editing and upregulation of NRF2-regulated antioxidant genes NADPH dehydrogenase quinone 1 (NQO1) (up to 11-fold), heme oxygenase 1 (HO1) (up to 11-fold), and GCLM (up to 2-fold). In primary human T cells, delivery of KEAP1 exon 2 target site 2-specific ATTO 550–labeled Cas9:guide RNA edited KEAP1 in ~40% cells and significantly (p ≤ 0.04) increased NQO1 (16-fold), HO1 (9-fold), and GCLM (2-fold) expression. To further enrich KEAP1-edited cells, ATTO 550–positive cells were sorted 24 h after electroporation. Assessment of ATTO 550–positive cells showed KEAP1 editing in ~55% cells. There was no detectable off-target cleavage in the top three predicted genes in the ATTO 550–positive cells. Gene expression analysis found significantly (p ≤ 0.01) higher expression of NQO1 mRNA in ATTO 550–positive cells compared with control cells. Flow cytometric assessment showed increased (p ≤ 0.01) frequency of CD4-, CD25-, and CD69-expressing KEAP1 edited cells whereas frequency of CD8- (p ≤ 0.01) and IL-17– (p ≤ 0.05) expressing cells was reduced compared with control cells. Similar experimental conditions resulted in significant KEAP1 editing, increased antioxidant gene expression, and frequency of CD69 and IL-10 positive cells in highly enriched KEAP1-edited regulatory T cells. KEAP1-edited T cells could potentially be used for treating multiple human diseases.

http://ift.tt/2C8C9d9

Differential Expression of CD8+ T Cell Cytotoxic Effector Molecules in Blood and Gastrointestinal Mucosa in HIV-1 Infection [MUCOSAL IMMUNOLOGY]

We previously reported that CD8⁺ T cells in human gastrointestinal mucosa exhibit reduced perforin expression and weak or impaired cytotoxic capacity compared with their counterparts in blood. Nevertheless, these cells degranulate and express cytokines and chemokines in response to cognate Ag. In addition to weak expression of perforin, earlier studies suggested differential regulation of perforin and granzymes (Gzms), with GzmA and B expressed by significantly higher percentages of mucosal CD8⁺ T cells than perforin. However, this topic has not been fully explored. The goal of this study was to elucidate the expression and coexpression patterns of GzmA, B, and K in conjunction with perforin in rectosigmoid CD8⁺ T cells during HIV-1 infection. We found that expression of both perforin and GzmB, but not GzmA or GzmK, was reduced in mucosa compared with blood. A large fraction of rectosigmoid CD8⁺ T cells either did not express Gzms or were single-positive for GzmA. Rectosigmoid CD8⁺ T cells appeared skewed toward cytokine production rather than cytotoxic responses, with cells expressing multiple cytokines and chemokines generally lacking in perforin and Gzm expression. These data support the interpretation that perforin and Gzms are differentially regulated, and display distinct expression patterns in blood and rectosigmoid T cells. These studies may help inform the development of strategies to combat HIV-1 and other mucosal pathogens.

http://ift.tt/2BEKh3P