The effect of subinhibitory concentrations of gentian violet on the germ tube formation by Candida albicans and its adherence to oral epithelial cells

Publication date: October 2017
Source:Archives of Oral Biology, Volume 82
Author(s): T. Mafojane, S.L. Shangase, M. Patel
ObjectiveThis study investigated the effect of subinhibitory concentrations of gentian violet on the germ tube formation by Candida albicans and its adherence ability to oral epithelial cells.MethodsThirty strains of C. albicans isolated from denture wearers, normal healthy individuals and HIV positive patients were used in the study. The antifungal property (Minimum Fungicidal Concentration) of gentian violet was determined at various time intervals using a microdilution technique. The effect of subinhibitory concentrations of gentian violet on the adherence ability (0.000244%) and on germ tube formation ((0.000244%, 0.000122%, 0.000061% and 0.000031%) was determined. In both experiments, water was used as a control. The test results were compared using the Kruskal-Wallis test.ResultsAt 60min a high concentration (0.0078%) of gentian violet was required to completely kill C. albicans. Subinhibitory concentrations of gentian violet significantly reduced the adherence ability of C. albicans by 57% (p<0.01) and equally inhibited germ tube formation (p<0.01) compared with the controls. The inhibition was concentration dependent, with up to 98% reduction at a concentration of 0.000244%. Germ tube reduction was significantly higher in the isolates from the HIV positive patients than in the isolates from denture wearers.ConclusionAt high concentrations, gentian violet killed C. albicans, whereas at subinhibitory concentrations it reduced its virulence by preventing the adherence ability and germ tube formation. This suggests that the beneficial effects of gentian violet would last beyond the fungicidal concentrations in the treatment of candidiasis.

Graphical abstract

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Podcast Interviews

ATA Members give podcast interviews on Thyroid Topics at www.docthyroid.com

Información Importante Sobre los Nódulos Tiroideos con la Dra Regina Castro de la Clínica Mayo
Interviewed and produced by Philip James | May 4, 2017 | Endocrine, Pathology, Podcast

You Have a Thyroid Nodule, What Happens Next? with Dr. Regina Castro from The Mayo Clinic
Interviewed and produced by Philip James | Apr 2, 2017 | Pathology, Podcast, Surgery

 

The post Podcast Interviews appeared first on American Thyroid Association.

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The Role of Patients

Shared decision-making affords patients and their families the autonomy to make difficult decisions after receiving comprehensive information about medical facts and treatment options. It is essential that patients' values are respected. The essential steps include first informing patients of the need for a decision, then explaining the various facts involved; after which, it is important to elicit patients' preferences and goals. Once the treatment options and outcomes important to patients are identified, an actual decision can be made. This activity is complex and requires a commitment of time and is enhanced through employment of a multidisciplinary team approach.

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Decision Making for Diagnosis and Management

The diagnosis and treatment of head and neck cancer is extremely complex. As a result, multiple medical providers are involved in a patient's care, and the multidisciplinary tumor boards provide a forum whereby they can share and discuss the intricacies of each individual patient's case. When recommendations are presented to the patient and decisions are to be finalized, the patient should benefit from the collective wisdom of a team of providers to achieve and implement a patient-centric and clinically sound consensus.

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Safer VL intubation: Don't lift or displace the tongue

Another tip for safer intubations.

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Flap Basics I

In many cases of complex facial defects, because of advanced cutaneous malignancies, primary wound closure is impossible. In these instances, ideal results can be obtained through recruitment of adjacent tissue with the use of local flaps. Advances in local flap techniques have raised the bar in facial reconstruction; however, acceptable results to surgeon and patient require high levels of planning and surgical technique. Defects resulting from Mohs surgery and other traumatic injuries can typically be repaired with local flaps. A well-planned and executed local flap can lead to excellent cosmetic results with minimal distortion of the surrounding facial landmarks.

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Anatomy of the Skin and the Pathogenesis of Nonmelanoma Skin Cancer

Skin is composed of the epidermis, dermis, and adnexal structures. The epidermis is composed of 4 layers—the stratums basale, spinosum, granulosum, and corneum. The dermis is divided into a superficial papillary dermis and deeper reticular dermis. Collagen and elastin within the reticular dermis are responsible for skin tensile strength and elasticity, respectively. The 2 most common kinds of nonmelanoma skin cancers are basal cell and squamous cell carcinoma. Both are caused by a host of environmental and genetic factors, although UV light exposure is the single greatest predisposing factor.

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Reconstruction of Cutaneous Nasal Defects

Mohs micrographic surgery has become the standard of care for the treatment of cutaneous malignancies. Reconstructing cutaneous defects of the nose can be challenging as form and function must be respected to the greatest extent possible. A wide range of reconstructive techniques are used. Secondary intent, primary closure, skin grafts, local flaps, and the interpolated workhorse flaps represent the spectrum of options, each with specific advantages and disadvantages. Vigilant postoperative care, including judicious use of adjunctive procedures, can improve outcomes. A subunit approach to reconstruction aids with surgical planning in order to achieve the best possible results.

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Scar Revision and Recontouring Post-Mohs Surgery

Following Mohs reconstruction, several options are available to improve the appearance of the resulting scars. It is critical that the patient has realistic goals before beginning any treatment because scars can be improved but never erased. The surgical and nonsurgical options aim to replace pre-existing scars with ones that are less conspicuous. This article addresses the different available options (listed in order of invasiveness) for improving scarring following Mohs reconstruction.

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The Physiology and Biomechanics of Skin Flaps

Facial skin defects created by Mohs micrographic surgery are commonly reconstructed using local cutaneous flaps from surrounding skin. To provide optimal survival and aesthetic outcomes, the cutaneous surgeon must command a thorough understanding of the complex vascular anatomy and physiology of the skin as well as the imperative physiologic and biomechanical considerations when elevating and transferring tissue via local skin flaps.

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Speech-evoked auditory brainstem responses in children with hearing loss

Publication date: August 2017
Source:International Journal of Pediatric Otorhinolaryngology, Volume 99
Author(s): Amineh Koravand, Rida Al Osman, Véronique Rivest, Catherine Poulin
ObjectiveThe main objective of the present study was to investigate subcortical auditory processing in children with sensorineural hearing loss.MethodsAuditory Brainstem Responses (ABRs) were recorded using click and speech/da/stimuli. Twenty-five children, aged 6–14 years old, participated in the study: 13 with normal hearing acuity and 12 with sensorineural hearing loss.ResultsNo significant differences were observed for the click-evoked ABRs between normal hearing and hearing-impaired groups. For the speech-evoked ABRs, no significant differences were found for the latencies of the following responses between the two groups: onset (V and A), transition (C), one of the steady-state wave (F), and offset (O). However, the latency of the steady-state waves (D and E) was significantly longer for the hearing-impaired compared to the normal hearing group. Furthermore, the amplitude of the offset wave O and of the envelope frequency response (EFR) of the speech-evoked ABRs was significantly larger for the hearing-impaired compared to the normal hearing group.ConclusionsResults obtained from the speech-evoked ABRs suggest that children with a mild to moderately-severe sensorineural hearing loss have a specific pattern of subcortical auditory processing. Our results show differences for the speech-evoked ABRs in normal hearing children compared to hearing-impaired children. These results add to the body of the literature on how children with hearing loss process speech at the brainstem level.



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Glucosamine has an antiallergic effect in mice with allergic asthma and rhinitis

Background

Glucosamine (GlcN) is generally used as a dietary supplement because of its antiinflammatory effects. We evaluated the antiallergic effect of GlcN in mice with allergic asthma and rhinitis.

Methods

Thirty-two mice were allocated equally into 4 groups (n = 8). In group A (control), we performed intraperitoneal/intranasal challenge using sterile saline. In group B (asthma/rhinitis), we used ovalbumin for intraperitoneal/intranasal challenge to induce allergic asthma and rhinitis. In groups C and D (GlcN treatment), mice were given 1% and 5% GlcN throughout the period of ovalbumin challenge, respectively. We measured serum total and ovalbumin-specific immunoglobulin E (IgE), cytokine titers (interleukin-1, -4, -5, -6, -10, and -17; tumor necrosis factor-α; and interferon-γ), and the number of inflammatory cells (eosinophils, neutrophils, lymphocytes) in bronchoalveolar lavage (BAL) fluid. We also performed histopathologic examination of the lung and nasal cavity. Finally, we performed real-time polymerase chain reaction for the genes Bcl-2, EC-SOD, VEGF, caspase-3, Bax, COX-2, Hif-1α, and heme oxygenase-1.

Results

Compared with group B, group D had significant serum total and ovalbumin-specific IgE decreases after GlcN treatment (p < 0.05). Titers for IL-4, IL-5, IL-6, and IL-17 in BAL fluid were significantly decreased in group D (p < 0.05). Eosinophils in BAL fluid were significantly decreased in group D compared with group B (p < 0.05). Groups C and D showed significant improvement of inflammation compared with group B. Group D had significant downregulation of EC-SOD, Bax, Hif-1α, and heme oxygenase-1 compared with group B.

Conclusion

GlcN had a significant antiallergic effect in mice with allergic asthma and rhinitis.

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Safety and efficacy of a bioabsorbable fluticasone propionate–eluting sinus dressing in postoperative management of endoscopic sinus surgery: a randomized clinical trial

Background

Postoperative wound healing after endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis (CRS) is an important factor in procedural success. Local steroids and separation of opposing mucosa are commonly implemented to optimize healing. A bioabsorbable, fluticasone propionate (FP)-eluting implant, SinuBand FP, was assessed for its safety and efficacy when used in patients with CRS and nasal polyps, who were indicated for ESS including bilateral anterior and posterior ethmoidectomy.

Methods

A first-in-human, randomized, partially double-blind, single-tertiary-referral-center, controlled trial enrolling 30 patients receiving 2 of 3 treatments (1 per sinus, intrapatient control): SinuBand FP, SinuBand (without FP), or standard nasal pack (Merocel®). Primary outcome measures were local safety, ocular safety (intraocular pressure [IOP], lens opacity), and 24-hour urine cortisol. Secondary measures (evaluated by independent review of postoperative video endoscopies) were ethmoid inflammation, polyp score, adhesion formation, and Lund-Kennedy score. Patient-reported outcomes of postoperative pain, nasal congestion, and nasal discharge were collected.

Results

Of 30 enrolled patients (used for safety analysis), 27 patients completed the trial. SinuBand FP showed local safety, ocular safety, and no significant change in 24-hour urine cortisol. SinuBand FP showed a trend to do better concerning inflammation. Concerning polyp score SinuBand FP did significantly better compared to Merocel (p = 0.03). No significance compared to SinuBand without corticosteroids (p = 0.97). Adhesions were comparable across treatments. Patient reported pain was nominally lower in the SinuBand group.

Conclusion

SinuBand FP was well tolerated and showed evidence of efficacy. A larger study is needed to further evaluate and confirm the benefits of SinuBand FP.

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Safety and tolerability of surfactant nasal irrigation

Background

Abnormal mucus composition and bacterial biofilms are thought to contribute to the pathophysiology of rhinosinusitis. Addition of a mucoactive surfactant to saline irrigation solution has been hypothesized to address these factors. We evaluated the safety and tolerability of a reformulated surfactant in a sample of normal subjects.

Methods

A total of 33 volunteers were randomly assigned to receive either surfactant solution or buffered saline at baseline in a controlled crossover study design. Each subject underwent rhinoscopic exam and in-office smell testing via the 40-question smell identification test (SIT). Those with non-normosmic results or active rhinitis symptoms were excluded. Subjects were instructed to irrigate twice daily with the selected solution for 1 week while keeping a daily diary. For week 2, treatment was stopped. During week 3, each group switched to the other treatment. Exam, SIT, and degree of congestion were assessed after each phase.

Results

Use of surfactant led to a marginal reduction in mean SIT score of 1.5 points, which was statistically significant (p = 0.012). A clinically meaningful reduction in SIT score, defined as ≥4 points, was observed in 18% (6/33) of subjects after surfactant vs 3% (1/33) after saline (p = 0.046). During the surfactant phase, moderate or severe congestion was reported in 29% (8/28) of subjects completing the diary. In contrast, only 6% (2/32) of subjects reported moderate congestion after the saline phase (p = 0.021).

Conclusion

In normal volunteers, surfactant nasal irrigation may be associated with tolerability issues due to congestion. A subset may experience reduction in olfactory acuity that appears reversible.

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Safer Intubation Tip #5

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Disease activity and mucosal healing in inflammatory bowel disease: a new role for histopathology?

Abstract

Histologic evaluation of disease activity in the setting of inflammatory bowel disease is gaining interest within the gastroenterology community. Recent data suggests that histologic measurements of inflammation in ulcerative colitis are more sensitive at detecting disease activity and perform better than endoscopic measurements in predicting clinical outcomes. Histologic measurements are also increasingly used in ulcerative colitis clinical trials to assess response to new therapies. Histologic measurements of disease activity are less well studied in Crohn's disease, but are gaining attention. Current published treatment algorithms in inflammatory bowel disease do not take into consideration histologic activity; however, this may change in the near future. In order for histologic measurements to be included in clinical decision-making, validated, reliable, and responsive histologic scoring systems are needed. In this review, the recent literature on the significance of histologic activity in both ulcerative colitis and Crohn's disease is summarized. Histologic scoring systems are also briefly discussed.

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SMARCA4-deficient pulmonary adenocarcinoma: clinicopathological, immunohistochemical, and molecular characteristics of a novel aggressive neoplasm with a consistent TTF1 neg /CK7 pos /HepPar-1 pos immunophenotype

Abstract

Alterations in SMARCA4, a member of the chromatin remodeling Switch Sucrose Non-Fermentable (SWI/SNF) complex, characterize a subset of non-small cell lung cancer (NSCLC), but detailed morphological and immunophenotypic description of this tumor type is lacking. We describe 20 NSCLC cases found on routine screening not to express SMARCA4 by immunohistochemistry (IHC). These tumors were stained for CK7, TTF1, SMARCA2, SMARCA4, SMARCB1, and HepPar-1 and analyzed for molecular alterations, using a 160 cancer-related gene panel including the full coding sequence of SMARCA4. Patients were eight females and 12 males aged 41 to 76 (median, 60). Of 18 tumors with detailed data, 14 presented with synchronous distant metastases (M1). Histological examination showed predominantly solid adenocarcinoma (n = 15), frankly rhabdoid (n = 3) and mucinous (n = 2) patterns. Except for the rhabdoid cases, all tumors showed at least focal unequivocal glands and lacked squamous differentiation, justifying a diagnosis of adenocarcinoma. IHC showed a distinctive uniform immunophenotype (CK7⁺/HepPar-1⁺/TTF1⁻) in 18/20 cases. Only 2/16 cases showed limited weak expression of neuroendocrine markers. EGFR mutations and EML4-ALK and ROS1 gene rearrangements were not found in any of the examined cases. Next-generation sequencing, using a 160 cancer-related gene panel, revealed concurrent SMARCA4 and TP53 mutations in nine of the 12 (75%) successfully tested cases. Our study highlights (1) the morphological diversity of SMARCA4-deficient lung adenocarcinoma, (2) the consistent absence of expression of TTF1 in the presence of expression of HepPar-1, (3) absence of EGFR driver mutations, and (4) frequent inactivating SMARCA4 mutations as underlying mechanism of the observed SMARCA4 protein loss. SMARCA4-deficient pulmonary adenocarcinoma is emerging as a distinctive, albeit phenotypically heterogeneous molecular subgroup of TTF1-negative NSCLC. Uniform HepPar-1 expression in this subset of NSCLC may represent a diagnostic pitfall and merits further studies to explore the mechanisms involved.

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Comparative evaluation of insertion torque and mechanical stability for self-tapping and self-drilling orthodontic miniscrews – an in vitro study

Abstract

Background

The aim of the present study was to evaluate the relationship between insertion torque and stability of miniscrews in terms of resistance against dislocation, then comparing a self-tapping screw with a self-drilling one.

Methods

Insertion torque was measured during placement of 30 self-drilling and 31 self-tapping stainless steel miniscrews (Leone SpA, Sesto Fiorentino, Italy) in synthetic bone blocks. Then, an increasing pulling force was applied at an angle of 90° and 45°, and the displacement of the miniscrews was recorded.

Results

The statistical analysis showed a statistically significant difference between the mean Maximum Insertion Torque (MIT) observed in the two groups and showed that force angulation and MIT have a statistically significant effect on miniscrews stability. For both the miniscrews, an angle of 90° between miniscrew and loading force is preferable in terms of stability.

Conclusions

The tested self-drilling orthodontic miniscrews showed higher MIT and greater resistance against dislocation than the self-tapping ones.

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QUILT-3.047: NANT Head and Neck Squamous Cell Carcinoma (HNSCC) Vaccine: Combination Immunotherapy in Subjects With HNSCC Who Have Progressed on or After Chemotherapy and PD-1/PD-L1 Therapy

Condition:   Head and Neck Squamous Cell Carcinoma
Interventions:   Biological: Avelumab;   Biological: Bevacizumab;   Drug: Capecitabine;   Biological: Cetuximab;   Drug: Cisplatin;   Drug: cyclophosphamide;   Drug: 5-Fluorouracil (5-FU);   Drug: fulvestrant;   Drug: leucovorin;   Drug: nab-paclitaxel;   Biological: nivolumab;   Drug: Lovaza;   Radiation: Stereotactic Body Radiation Therapy;   Biological: ALT-803;   Biological: ETBX-011;   Biological: ETBX-021;   Biological: ETBX-051;   Biological: ETBX-061;   Biological: GI-4000;   Biological: GI-6207;   Biological: GI-6301;   Biological: haNK
Sponsor:   NantCell, Inc.
Not yet recruiting - verified May 2017

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Phase 2 Trial of Apatinib Mesylate in Locally Advanced/Metastatic Differentiated Thyroid Carcinoma

Condition:   Differentiated Thyroid Carcinoma
Intervention:   Drug: Apatinib Mesylate
Sponsor:   Tianjin Medical University Cancer Institute and Hospital
Recruiting - verified March 2017

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"Model for Early Allograft Function" outperforms "Early Allograft Dysfunction" as a predictor of transplant survival.

Background: The Model of Early Allograft Function (MEAF) grades the severity of liver graft dysfunction. Unlike the categorical Early Allograft Dysfunction (EAD) classification, MEAF is a continuous score, based on bilirubin, international normalised ratio, and alanine aminotransferase within 3 days posttransplant. Methods: Multivariable regression models were used to validate the MEAF score in 660 liver-only transplants performed between 2000-2014. MEAF performance for prediction of transplant survival was compared with that of EAD in univariable and multivariable models by means of Harrell's c-indices, integrated discrimination improvement, and net reclassification improvement. Results: Median donor and recipient age was 52y (IQR 41-62) and 58y (50-64), respectively. MELD-score was 15 (11-21), cold ischemia time 8.0h (6.4-9.7), MEAF 4 (3-6). EAD occurred in 182 (27.6%) cases. Transplant survival was 93%, 90%, and 88% at 3, 6, and 12 months. Both MEAF and EAD were independent predictors of transplant survival within 3, 6, and 12 months. MEAF outperformed EAD as predictor of transplant survival, either when used as a standalone parameter or when corrected for additional independent predictors of transplant survival. Conclusion: MEAF is a more accurate predictor of transplant loss than the commonly used EAD classification. As a continuous score grading graft dysfunction, MEAF provides additional, granulated information that could be used both clinically and as a surrogate endpoint of transplant survival in clinical trials. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.

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Plasma Exosomes from HLA-Sensitized Kidney Transplant Recipients Contain mRNA Transcripts Which Predict Development of Antibody-Mediated Rejection.

Background: Sensitization to human leukocyte antigens (HLA) remains a significant immunologic barrier to successful transplantation. Identifying immune mechanisms responsible for antibody-mediated rejection (ABMR) is an important goal. Here we explored the possibility of predicting the risk for ABMR by measuring mRNA transcripts of ABMR-associated genes in plasma exosomes from kidney transplant patients. Methods: Total RNA was extracted from exosomes purified from 152 EDTA-plasma samples of 64 patients (18 ABMR, 8 cell-mediated rejection [CMR], 38 no rejection in desensitized (DES) and non-desensitized (non-DES) control groups) for reverse transcription into cDNA, preamplification and then real time quantitative polymerase chain reaction (qPCR) for 21 candidate genes. The mRNA transcript levels of each gene were calculated. Comparisons were made among 4 patient groups for each gene and also for a gene combination score based on selected genes. Results: Among 21 candidate genes, we identified multiple genes (gp130, CCL4, TNF[alpha], SH2D1B, CAV1, DARC) whose mRNA transcript levels in plasma exosomes significantly increased among ABMR compared to CMR and/or control patients. A gene combination score calculated from 4 genes of gp130, SH2D1B, TNF[alpha] and CCL4 was significantly higher in the ABMR than the CMR (p

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Comparative Evaluation of [alpha]CD40 (2C10R4) and [alpha]CD154 (5C8H1 and IDEC-131) in a Nonhuman Primate Cardiac Allotransplant Model.

Background: Specific blockade of T cell costimulation pathway is a promising immunomodulatory approach being developed to replace our current clinical immunosuppression therapies. The goal of this study is to compare results associated with 3 monoclonal antibodies directed against the CD40/CD154 T cell costimulation pathway. Methods: Cynomolgus monkey heterotopic cardiac allograft recipients were treated with either IDEC-131 (humanized [alpha]CD154, n=9), 5C8H1 (mouse-human chimeric [alpha]CD154, n=5), or 2C10R4 (mouse-rhesus chimeric [alpha]CD40, n=6) monotherapy using a consistent, comparable dosing regimen for 3 months after transplant. Results: Relative to the previously reported IDEC-131 treated allografts, median survival time (MST 35+/-31 days) was significantly prolonged in both 5C8H1 (142+/-26, p

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Magnetic behaviour of hydrogenated Ho(1-x)Mm(x)Co(2) (x=0-0.4) alloys

Srinivas, G; Ramaprabhu, S; (2010) Magnetic behaviour of hydrogenated Ho(1-x)Mm(x)Co(2) (x=0-0.4) alloys. Journal of Alloys and Compounds , 497 (1-2) pp. 28-31. 10.1016/j.jallcom.2010.02.187 .

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Multi-Objective Genetic Algorithms for the minimisation of the Life Cycle Carbon Footprint and Life Cycle Cost of the refurbishment of a residential complex's envelope: A case study

Schwartz, Y; Raslan, R; Mumovic, D; (2015) Multi-Objective Genetic Algorithms for the minimisation of the Life Cycle Carbon Footprint and Life Cycle Cost of the refurbishment of a residential complex's envelope: A case study. In: Samuelson, H and Bhooshan, S and Goldstein, R, (eds.) SimAUD '15: Proceedings of the Symposium on Simulation for Architecture & Urban Design. (pp. pp. 189-196). Society for Modeling & Simulation International (SCS): Alexandria, VA, USA.

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DeepEar: Robust Smartphone Audio Sensing in Unconstrained Acoustic Environments using Deep Learning

Lane, ND; Georgiev, P; Qendro, L; (2015) DeepEar: Robust Smartphone Audio Sensing in Unconstrained Acoustic Environments using Deep Learning. In: Miyahara, H and Tokuda, H and Mase, K and Langheinrich, M, (eds.) Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing. (pp. pp. 283-294). Association for Computing Machinery: Osaka, Japan. Green open access

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Goodbye Warm Front: Evaluating the Delivery of Energy Efficiency Retrofits in Low-income Homes in England from 2005 to 2012

Hamilton, IG; Agnolucci, P; Oreszczyn, T; (2015) Goodbye Warm Front: Evaluating the Delivery of Energy Efficiency Retrofits in Low-income Homes in England from 2005 to 2012. In: Proceedings of 2015 IEPEC Conference. IEPEC: Long Beach, CA, USA. Green open access

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Can deep learning revolutionize mobile sensing?

Lane, ND; Georgiev, P; (2015) Can deep learning revolutionize mobile sensing? In: Manweiler, J and Choudhury, RR and Rozner, E and Lane, N, (eds.) Proceedings of the 16th International Workshop on Mobile Computing Systems and Applications. (pp. pp. 117-122). Association for Computing Machinery: Santa Fe, New Mexico, USA. Green open access

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A theoretical elucidation of glucose interaction with HSA's domains

Nasiri, R; Bahrami, H; Zahedi, M; Moosavi-Movahedi, AA; Sattarahmady, N; (2010) A theoretical elucidation of glucose interaction with HSA's domains. Journal of Biomolecular Structure and Dynamics , 28 (2) pp. 211-226. 10.1080/07391102.2010.10507354 .

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Modified Radius Directed Equaliser for High Order QAM

Lavery, D; Paskov, M; Maher, R; Savory, SJ; Bayvel, P; (2015) Modified Radius Directed Equaliser for High Order QAM. In: Capmany, J and Junyent, G and Sales, S and Muñoz, R, (eds.) Proceedings of 41st European Conference on Optical Communication (ECOC). IEEE: Valencia, Spain. Green open access

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Social Touch Gesture Recognition using Random Forest and Boosting on Distinct Feature Sets

Gaus, YFA; Olugbade, T; Jan, A; Qin, R; Liu, J; Zhang, F; Meng, H; Gaus, YFA; Olugbade, T; Jan, A; Qin, R; Liu, J; Zhang, F; Meng, H; Bianchi-Berthouze, N; - view fewer (2015) Social Touch Gesture Recognition using Random Forest and Boosting on Distinct Feature Sets. In: Zhang, Z and Cohen, P and Bohus, D and Horaud, R, (eds.) Proceedings of the 2015 ACM on International Conference on Multimodal Interaction. (pp. pp. 399-406). Association for Computing Machinery: Seattle, WA, USA. Green open access

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Optical Non-Contact Railway Track Measurement with Static Terrestrial Laser Scanning to Better than 1.5mm RMS

Soni, A; Robson, S; Gleeson, B; (2015) Optical Non-Contact Railway Track Measurement with Static Terrestrial Laser Scanning to Better than 1.5mm RMS. In: Krumov, YA and Potsiou, C, (eds.) Proceedings of FIG Working Week 2015 - From the Wisdom of the Ages to the Challenges of the Modern World. The Chamber of Graduated Surveyors, Bulgaria: Sofia, Bulgaria. Green open access

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Public understanding of the purpose of cancer screening: A population-based survey

Chorley, AJ; Hirst, Y; Vrinten, C; von Wagner, C; Wardle, J; Waller, J; (2017) Public understanding of the purpose of cancer screening: A population-based survey. Journal of Medical Screening 10.1177/0969141317699440 . (In press). Green open access

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How to study spoken language understanding: a survey of neuroscientific methods

Rodd, JM; Davis, MH; (2017) How to study spoken language understanding: a survey of neuroscientific methods. Language, Cognition and Neuroscience 10.1080/23273798.2017.1323110 . (In press).

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Early Endarterectomy Carries a Lower Procedural Risk Than Early Stenting in Patients With Symptomatic Stenosis of the Internal Carotid Artery: Results From 4 Randomized Controlled Trials

Rantner, B; Kollerits, B; Roubin, GS; Ringleb, PA; Jansen, O; Howard, G; Hendrikse, J; Rantner, B; Kollerits, B; Roubin, GS; Ringleb, PA; Jansen, O; Howard, G; Hendrikse, J; Halliday, A; Gregson, J; Eckstein, H-H; Calvet, D; Bulbulia, R; Bonati, LH; Becquemin, J-P; Algra, A; Brown, MM; Mas, J-L; Brott, TG; Fraedrich, G; Carotid Stenosis Trialists' Collaboration, .; - view fewer (2017) Early Endarterectomy Carries a Lower Procedural Risk Than Early Stenting in Patients With Symptomatic Stenosis of the Internal Carotid Artery: Results From 4 Randomized Controlled Trials. Stroke , 48 (6) pp. 1580-1587. 10.1161/STROKEAHA.116.016233 .

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Joint CHEST-SGP Congress 2017. Basel, Switzerland, 7-9 June 2017: Abstracts

Respiration 2017;94:76-156

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Graphene Oxide Framework Materials: Theoretical Predictions and Experimental Results

Burress, JW; Gadipelli, S; Ford, J; Simmons, JM; Zhou, W; Yildirim, T; (2010) Graphene Oxide Framework Materials: Theoretical Predictions and Experimental Results. [Rapid communication]. Angewandte Chemie International Edition , 49 (47) pp. 8902-8904. 10.1002/anie.201003328 .

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The healthy human cerebellum engaging in complex patterns: An fMRI study

Alahmadi, A; Pardini, M; Samson, R; Friston, K; Toosy, A; D'Angelo, E; Wheeler-Kingshott, C; (2015) The healthy human cerebellum engaging in complex patterns: An fMRI study. In: Chung, C and Griswold, MA and Jones, DK and Reeder, SB, (eds.) Proceedings of ISMRM 23rd Annual Meeting & Exhibition. The International Society for Magnetic Resonance in Medicine: Toronto, Ontario, Canada.

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Identity projects in complementary and mainstream schools: the views of Albanian and Bulgarian students in England

Tereshchenko, A; Archer, L; (2015) Identity projects in complementary and mainstream schools: the views of Albanian and Bulgarian students in England. Research Papers in Education , 30 (3) pp. 347-365. 10.1080/02671522.2014.919521 .

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Adsorption Sites and Binding Nature of CO 2 in Prototypical Metal−Organic Frameworks: A Combined Neutron Diffraction and First-Principles Study

Wu, H; Simmons, JM; Gadipelli, S; Zhou, W; Yildirim, T; (2010) Adsorption Sites and Binding Nature of CO 2 in Prototypical Metal−Organic Frameworks: A Combined Neutron Diffraction and First-Principles Study. [Letter]. The Journal of Physical Chemistry Letters , 1 (13) pp. 1946-1951. 10.1021/jz100558r .

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A new family of metal borohydride ammonia borane complexes: Synthesis, structures, and hydrogen storage properties

Wu, H; Zhou, W; Pinkerton, FE; Meyer, MS; Gadipelli, S; Yildirim, T; Udovic, TJ; Wu, H; Zhou, W; Pinkerton, FE; Meyer, MS; Gadipelli, S; Yildirim, T; Udovic, TJ; Rush, JJ; - view fewer (2010) A new family of metal borohydride ammonia borane complexes: Synthesis, structures, and hydrogen storage properties. Journal of Materials Chemistry , 20 (31) p. 6550. 10.1039/c0jm01542c .

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Exploring mobile news reading interactions for news app personalisation

Constantinides, M; Dowell, J; Johnson, D; Malacria, S; (2015) Exploring mobile news reading interactions for news app personalisation. In: Boring, S and Rukzio, E and Gellersen, H and Hinckley, K, (eds.) Mobile HCI'15: Proceedings of the 17th International Conference on Human-Computer Interaction with Mobile Devices and Services. (pp. pp. 457-462). Association for Computing Machinery: Copenhagen, Denmark. Green open access

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Multi-Objective Genetic Algorithms for the minimisation of the Life Cycle Carbon Footprint and Life Cycle Cost of the refurbishment of a residential complex's envelope: A case study

Schwartz, Y; Raslan, R; Mumovic, D; (2015) Multi-Objective Genetic Algorithms for the minimisation of the Life Cycle Carbon Footprint and Life Cycle Cost of the refurbishment of a residential complex's envelope: A case study. In: Samuelson, H and Bhooshan, S and Goldstein, R, (eds.) SimAUD '15: Proceedings of the Symposium on Simulation for Architecture & Urban Design. (pp. pp. 189-196). Society for Modeling & Simulation International (SCS): Alexandria, VA, USA.

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Magnetic behaviour of hydrogenated Ho(1-x)Mm(x)Co(2) (x=0-0.4) alloys

Srinivas, G; Ramaprabhu, S; (2010) Magnetic behaviour of hydrogenated Ho(1-x)Mm(x)Co(2) (x=0-0.4) alloys. Journal of Alloys and Compounds , 497 (1-2) pp. 28-31. 10.1016/j.jallcom.2010.02.187 .

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Goodbye Warm Front: Evaluating the Delivery of Energy Efficiency Retrofits in Low-income Homes in England from 2005 to 2012

Hamilton, IG; Agnolucci, P; Oreszczyn, T; (2015) Goodbye Warm Front: Evaluating the Delivery of Energy Efficiency Retrofits in Low-income Homes in England from 2005 to 2012. In: Proceedings of 2015 IEPEC Conference. IEPEC: Long Beach, CA, USA. Green open access

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Early Endarterectomy Carries a Lower Procedural Risk Than Early Stenting in Patients With Symptomatic Stenosis of the Internal Carotid Artery: Results From 4 Randomized Controlled Trials

Rantner, B; Kollerits, B; Roubin, GS; Ringleb, PA; Jansen, O; Howard, G; Hendrikse, J; Rantner, B; Kollerits, B; Roubin, GS; Ringleb, PA; Jansen, O; Howard, G; Hendrikse, J; Halliday, A; Gregson, J; Eckstein, H-H; Calvet, D; Bulbulia, R; Bonati, LH; Becquemin, J-P; Algra, A; Brown, MM; Mas, J-L; Brott, TG; Fraedrich, G; Carotid Stenosis Trialists' Collaboration, .; - view fewer (2017) Early Endarterectomy Carries a Lower Procedural Risk Than Early Stenting in Patients With Symptomatic Stenosis of the Internal Carotid Artery: Results From 4 Randomized Controlled Trials. Stroke , 48 (6) pp. 1580-1587. 10.1161/STROKEAHA.116.016233 .

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Optical Non-Contact Railway Track Measurement with Static Terrestrial Laser Scanning to Better than 1.5mm RMS

Soni, A; Robson, S; Gleeson, B; (2015) Optical Non-Contact Railway Track Measurement with Static Terrestrial Laser Scanning to Better than 1.5mm RMS. In: Krumov, YA and Potsiou, C, (eds.) Proceedings of FIG Working Week 2015 - From the Wisdom of the Ages to the Challenges of the Modern World. The Chamber of Graduated Surveyors, Bulgaria: Sofia, Bulgaria. Green open access

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Delayed diagnosis of subcutaneous dirofilariasis following a mosquito bite sustained in Germany

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Can deep learning revolutionize mobile sensing?

Lane, ND; Georgiev, P; (2015) Can deep learning revolutionize mobile sensing? In: Manweiler, J and Choudhury, RR and Rozner, E and Lane, N, (eds.) Proceedings of the 16th International Workshop on Mobile Computing Systems and Applications. (pp. pp. 117-122). Association for Computing Machinery: Santa Fe, New Mexico, USA. Green open access

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Radiosensitization by BRAF inhibitors

Background

Increased skin toxicity during combination therapy with a BRAF inhibitor and radiation therapy has recently been reported.

Material and Methods

We present seven melanoma patients with non-resectable stage III or IV disease and concomitant treatment with a BRAF inhibitor and radiation therapy.

Results

In all patients, combination therapy yielded a good local response. Only two patients, both on vemurafenib, showed severe radiation dermatitis (CTCAE grade 3/4) after one and two weeks, respectively, resulting in interruption of BRAF inhibitor treatment. The respective cumulative radiation dose was 10 Gy and 35 Gy. The remaining vemurafenib patients displayed only mild radiation dermatitis CTCAE grade 2; the only dabrafenib patient CTCAE grade 1. In one patient, recall dermatitis was diagnosed 14 days after completion of radiation therapy with a cumulative dose of 30 Gy.

Conclusions

Severe skin toxicity caused by BRAF inhibitor-induced radiosensitization is not common and usually amenable to treatment. Thus, combination treatment should remain a therapeutic option, especially in melanoma patients characterized by aggressive tumor growth. Although there is an increased risk of skin toxicity during combination therapy, it is usually well tolerated by most patients. Sequential – instead of simultaneous – treatment does not seem to prevent such toxicity reactions.

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DeepEar: Robust Smartphone Audio Sensing in Unconstrained Acoustic Environments using Deep Learning

Lane, ND; Georgiev, P; Qendro, L; (2015) DeepEar: Robust Smartphone Audio Sensing in Unconstrained Acoustic Environments using Deep Learning. In: Miyahara, H and Tokuda, H and Mase, K and Langheinrich, M, (eds.) Proceedings of the 2015 ACM International Joint Conference on Pervasive and Ubiquitous Computing. (pp. pp. 283-294). Association for Computing Machinery: Osaka, Japan. Green open access

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A theoretical elucidation of glucose interaction with HSA's domains

Nasiri, R; Bahrami, H; Zahedi, M; Moosavi-Movahedi, AA; Sattarahmady, N; (2010) A theoretical elucidation of glucose interaction with HSA's domains. Journal of Biomolecular Structure and Dynamics , 28 (2) pp. 211-226. 10.1080/07391102.2010.10507354 .

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Public understanding of the purpose of cancer screening: A population-based survey

Chorley, AJ; Hirst, Y; Vrinten, C; von Wagner, C; Wardle, J; Waller, J; (2017) Public understanding of the purpose of cancer screening: A population-based survey. Journal of Medical Screening 10.1177/0969141317699440 . (In press). Green open access

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How to study spoken language understanding: a survey of neuroscientific methods

Rodd, JM; Davis, MH; (2017) How to study spoken language understanding: a survey of neuroscientific methods. Language, Cognition and Neuroscience 10.1080/23273798.2017.1323110 . (In press).

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Efficient cross-coupling of aryl chlorides with aryl Grignard reagents (Kumada reaction) mediated by a palladium/imidazolium chloride system

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Thermodynamics of addition of H-2, CO, N-2, and C-H bonds to M((PPr3)-Pr-i)(2)Cl (M = Ir, Rh) : an unprecedented metal-carbonyl bond strength

The thermodynamics of interconversion of various complexes containing the unit IrL*Cl-2 (L* = P(Pr-i)(3)) have been investigated by calorimetry and equilibrium measurements. These complexes span a wide range of configurations including four- and five-coordinate d(8) (IrL*2ClL', IrL*Cl-2(CO)(2)) and five- and six-coordinate d(6) (IrL*2ClRH and IrL*2ClRH(CO)). On the basis of kinetic experiments, a lower limit to the Ir-Nz bond dissociation enthalpy (BDE) of IrL*Cl-2(N-2) has been determined (36 kcal/mol). Using this value as an "anchor", in conjunction with the relative addition enthalpies obtained calorimetrically, it is possible to derive lower limits for the absolute exothermicities of H-2 (48 kcal/mol) and CO (72 kcal/mol) addition to IrL*Cl-2; estimates can also be made for the addition of benzene and acetylene C-H bonds. These values are unusually high; indeed, the magnitude of the Ir-CO BDE is unprecedented. In addition, kinetic methods have been used to determine a lower limit of 29 kcal/mol to the Rh-N-2 BDE of RhL*Cl-2(N-2). Combined with previous calorimetric measurements on rhodium complexes, this value permits the calculation of lower limits to the absolute exothermicities of addition to RhL*Cl-2 for numerous small molecules including H-2, CO, N-2, C2H4, and aldehydic C-H bonds. The results of electronic structure calculations (approximate DFT; PMe3 used to model (PPr3)-Pr-i) are in excellent agreement with the relative experimental enthalpies, while the absolute values calculated for addition to IrL2Cl are significantly greater than the experimentally determined lower limits. Addition of a methane C-H bond is calculated to be significantly less favorable than addition of benzene or acetylene C-H bonds, in accord with the fact that IrL*Cl-2(alkyl)H complexes have not been reported. The significant differences in the enthalpies of addition for these three types of C-H bonds are briefly analyzed.

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Full title with Editorial board members

Publication date: July 2017
Source:International Journal of Psychophysiology, Volume 117





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On the origin of selective nitrous oxide N-N bond cleavage by three-coordinate molybdenum(III) complexes

Reaction of Mo(N[R]Ar)(3) (R = Bu-t or (CD3)(2)CH3) with N2O gives rise exclusively to a 1: 1 mixture of nitride NMo(N[R]Ar)(3) and nitrosyl ONMo(N[R]Ar)(3), rather than the known oxo complex OMo(N[R]Ar)(3) and dinitro-en. Solution calorimetry measurements were used to determine the heat of reaction of Mo(N[R]Ar)3 with N2O and, independently, the heat of reaction of Mo(N[R]Ar)3 with NO. Derived from the latter measurements is an estimate (155.3 +/- 3.3 kcal . mol(-1)) of the molybdenum-nitrogen bond dissociation enthalpy for the terminal nitrido complex, NMo(N[R]Ar)(3). Comparison of the new calorimetry data with those obtained previously for oxo transfer to Mo(N[R]Ar)(3) shows that the nitrous oxide N-N bond cleavage reaction is under kinetic control. Stopped-flow kinetic measurements revealed the reaction to be first order in both Mo(N[R]Ar)(3) and N2O, consistent with a mechanism featuring post-rate-determining dinuclear N-N bond scission, but also consistent with cleavage of the N-N bond at a single metal center in a mechanism requiring the intermediacy of nitric oxide. The new 2-adamantyl-substituted molybdenum complex Mo(N[2-Ad]Ar)(3) was synthesized and found also to split N2O, resulting in a 1:1 mixture of nitrosyl and nitride products;,the reaction exhibited first-order kinetics and was found to be ca. 6 times slower than that for the tert-butyl-substituted derivative. Discussed in conjunction with studies of the 2-adamantyl derivative Mo(N[2-Ad]Ar)(3) is the role of ligand-imposed steric constraints on small-molecule, e.g. N-2 and N2O, activation reactivity. Bradley's chromium complex Cr((NPr2)-Pr-i)(3) was found to be competitive with Mo(N[R]Ar)(3) for NO binding, while on its own exhibiting no reaction with N2O. Competition experiments permitted determination of ratios of second-order rate constants for NO binding by the two molybdenum complexes and the chromium complex. Analysis of the product mixtures resulting from carrying out the N2O cleavage reactions with Cr((NPr2)-Pr-i)(3) present as an in situ NO scavenger rules out as dominant any mechanism involving the intermediacy of NO. Simplest and consistent with all the available data is a post-rate-determining bimetallic N-N scission process. Kinetic funneling of the reaction as indicated is taken to be governed by the properties of nitrous oxide as a ligand, coupled with the azophilic nature of three-coordinate molybdenum(III) complexes.

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IOP-details

Publication date: July 2017
Source:International Journal of Psychophysiology, Volume 117





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Instructions to Authors

Publication date: July 2017
Source:International Journal of Psychophysiology, Volume 117





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Increased Frequency of Bronchiolar Histotypes in Lung Carcinomas Associated with Idiopathic Pulmonary Fibrosis

Abstract

Aims

The association between lung cancer and idiopathic pulmonary fibrosis (IPF) is well-known, however the significance of this association is poorly understood. Bronchiolar honeycomb cysts have been proposed as possible precursors for development of carcinoma, but limited evidence of this hypothesis is available.

Methods and results

Thirty-three lung carcinomas arising in patients with IPF have been analyzed using a panel of immunohistochemical markers. The antibodies included pneumocyte markers (TTF1, Napsin-A, SPA1), the goblet cell marker MUC5AC, markers of basal/squamous cell differentiation (CK5/6, ΔN-p63) and markers related to enteric differentiation (CDX2, MUC2, CK20, villin). A series of 100 consecutive lung adenocarcinomas arising in smokers without IPF was investigated as control. All carcinomas arising in IPF were peripherally located at imaging analysis. The diagnosis were: 8 squamous cell carcinomas, 20 adenocarcinomas, 3 small-cell carcinomas (including one composite small-cell and adenocarcinoma) and 2 large cell carcinomas. Among adenocarcinomas, a "pneumocyte" profile (TTF1, Napsin-A, SPA1 triple-positive) was observed in 7/20 (35% versus 84% in non-IPF, p-value 0.0001). The remaining 13 adenocarcinomas (65%) exhibited rare histotypes: 4 invasive mucinous adenocarcinomas (20% in IPF versus 1% in non-IPF, p-value 0.002), 7 tumors (35%) were characterized by variable expression of markers of enteric differentiation and 2 tumors (10%) showed a peculiar "basaloid" component.

Conclusions

The immunohistochemical characterization of carcinomas arising in IPF shows striking divergence from those observed in non-IPF. The prevalence of rare entities exhibiting bronchiole-related markers is in line with the hypothesis that these tumors arise from transformed small airways in honeycomb lung areas where abnormal bronchiolar proliferation takes place.

This article is protected by copyright. All rights reserved.

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Olefin metathesis-active ruthenium complexes bearing a nucleophilic carbene ligand

The reaction of [Cp*RuCl](4) (1, Cp* = eta(5)-C5Me5) with the carbene ligand 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes) affords a coordinatively unsaturated Cp*Ru(IMes)Cl (3) complex in 86% isolated yield. Solution calorimetric results in this system provide information concerning the electron donor properties of the carbene ligand, which are very similar to those of PCy3. Structural information from single-crystal X-ray studies for complex 3 allows the determination of steric parameters associated with this ligand. The thermochemical information is used to predict the magnitude of the enthalpic driving force behind substitution reactions involving RuCl2(=C(H)Ph)(PCy3)(2) (1) and the carbene ligand, IMes, affording the RuCl2(=C(H)Ph)(PCy3)(IMes) (6) complex in high yield. A similar mixed carbene/phosphine ruthenium complex, RuCl2(=C(H)Ph)(PPh3)(IMes), can also be isolated from RuCl2(=C(H)Ph)(PPh3)(2) and the IMes ligand. A single-crystal X-ray diffraction study has been performed on 6. The thermal stability of these mixed phosphine/carbene ruthenium carbene complexes has been studied at 60 degrees C in toluene. Their catalytic activity has been evaluated for the ring closing metathesis of diethyldiallylmalonate.

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Four-coordinate molybdenum chalcogenide complexes relevant to nitrous oxide N-N bond cleavage by three-coordinate molybdenum(III) : synthesis, characterization, reactivity, and thermochemistry

The terminal chalcogenide complexes Mo(E)(N[R]Ar)(3) (R = C(CD3)(2)CH3, Ar = 3,5-C6H3Me2), where E = O, S, Se, and Te, were prepared by reaction of the three-coordinate complex Mo(N[R]Ar)(3) with ONC5H5, S-8 or SC2H4, Se, and Te/PEt3 in respective yields of 72, 63, 80, and 73%. The Mo(E)(N[R]Ar)(3) complexes were studied by EPR, SQUID, cyclic voltammetry, 2H NMR spectroscopy, and single-crystal X-ray diffraction. Thermolysis of each Mo(E)(N[R]Ar)(3) complex resulted in (formal) tert-butyl radical elimination giving molybdenum(VI) chalcogenide complexes Mo(E)(NAr)(N[R]Ar)(2) in yields of 85 (E = O), 84 (E = S), 64 (E = Se) and 40% (E = Te). tert-Butyl elimination kinetics were monitored (H-2 NMR) over a 62-104 degrees C temperature range for Mo(O)(N[R]Ar)(3), and from 66 to 93 degrees C for Mo(S)(N[R]Ar)(3); in both cases, a first-order decay was observed. Treatment of Mo(O)(N[R]Ar)(3) with iodine (0.5 equiv) provided [Mo(O)(N[R]Ar)(3)][I] in 88% yield. The triflate salt [Mo(O)(N[R]Ar)(3)][O3SCF3] was prepared similarly (71% yield) upon treatment of Mo(O)(N[R]Ar)(3) with [Cp2Fe][O3SCF3]. Small-scale experiments monitored by H-1 NMR spectroscopy established that Mo(N[R]Ar)(3) deoxygenates OSMe2, NO2, and SO2 but fails to deoxygenate CO2. Also essentially inert to Mo(N[R]Ar)(3) were found to be OPPh3, t-BuNCO, and O2SMe2. Treatment of Mo(N[R]Ar)(3) with Se2Ph2 provided Mo(SePh)(N[R]Ar)(3) in 72% yield. Treatment of Mo(N[R]Ar)(3) with CS2 led to Mo- (S)(N[R]Ar)(3) and (mu-CS)[Mo(N[R]Ar)(3)](2); the latter was isolated in 42% yield and was the subject of an X-ray diffraction study. Bond dissociation enthalpies D(MoE) for Mo(E)(N[R]Ar)(3) (E = O and S) were experimentally determined to be 155.6 +/- 1.6 and 104.4 +/- 1.2 kcal mol(-1), respectively. MoE bond lengths predicted by density functional B3LYP calculations (lanl2dz + d(E) basis set) for the model complexes Mo(E)(NH2)(3) (E = O, S, Se, and Te) were found to compare favorably with the experimentally determined MoE bond lengths. Predicted bond dissociation enthalpies D(MoE) for the hypothetical complexes Mo(E)(NH2)(3) are 91 (E = Se) and 71 (E = Te) kcal mol(-1). A key finding is that Mo(N[R]Ar)(3) selectively splits the nitrous oxide N-N bond to give Mo(N)(NIR]Ar)(3) and Mo(NO)(N[R]Ar)(3), despite the fact that the oxo complex Mo(O)(N[R]Ar)(3) possesses a very strong Mo-O bond and can be prepared by an alternate route.

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Thermodynamics of phosphine coordination to the [PNP]Rh-I fragment : an example of the importance of reorganization energies in the assessment of metal-ligand 'Bond Strengths'

Reaction enthalpies of the complexes [RPNP]Rh(COE) ([RPNP] = N(SiMe2CH2PPh2)(2), N(SiMe2-(CH2PPr2)-Pr-i)(2); COE = cyclooctene) with a series of phosphine ligands and CO have been measured by solution calorimetry. The measured enthalpies span range of ca. 40 kcal/mol. These systems favor coordination of strong pi-acceptor/weak sigma-donor ligands as shown by the trend in Delta H-rxn: CO much greater than Ppyrl(3)' > Ppyrl(3) > PPhpyrl(2) > PPh(2)pyrl > PPh3. This trend is exactly the opposite of that observed in another square planar rhodium(I); system, trans-RhCl(CO)(PZ(3))(2). With the exception of CO, the ligands investigated are isosteric, and so the observed trends are electronic in nature. Single-crystal X-ray diffraction studies on several of theses complexes ([RPNP]RhL where R, L = Ph, PPh3; Ph, Ppyrl(3); Ph, CO; Pr-i, PPh3; Pr-i, Ppyrl(3); Pr-i, CO; Pr-i, COE) have been performed. Although the structural trends are readily understood in:terms of the electronic (donor/acceptor) nature of each ligand array, it is not obvious that the structural data predict the trends or, in particular, the trend reversal in Delta H-rxn in the two Rh(I) systems. Rather, these results illustrate the importance of reorganization energies in thermodynamic analyses of metal-ligand bonding, especially in the presence of synergistic bonding involving sigma-donor, pi-donor, and pi-acceptor ligands, interacting through shared metal orbitals (electron push-pull). In such cases the interpretation of a metal-ligand bond dissociation enthalpy (D) as an intrinsic, universal, and transferable property of that bond (e.g., a ''bond strength") is an invalid proposition.

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On the origin of selective nitrous oxide N-N bond cleavage by three-coordinate molybdenum(III) complexes

Reaction of Mo(N[R]Ar)(3) (R = Bu-t or (CD3)(2)CH3) with N2O gives rise exclusively to a 1: 1 mixture of nitride NMo(N[R]Ar)(3) and nitrosyl ONMo(N[R]Ar)(3), rather than the known oxo complex OMo(N[R]Ar)(3) and dinitro-en. Solution calorimetry measurements were used to determine the heat of reaction of Mo(N[R]Ar)3 with N2O and, independently, the heat of reaction of Mo(N[R]Ar)3 with NO. Derived from the latter measurements is an estimate (155.3 +/- 3.3 kcal . mol(-1)) of the molybdenum-nitrogen bond dissociation enthalpy for the terminal nitrido complex, NMo(N[R]Ar)(3). Comparison of the new calorimetry data with those obtained previously for oxo transfer to Mo(N[R]Ar)(3) shows that the nitrous oxide N-N bond cleavage reaction is under kinetic control. Stopped-flow kinetic measurements revealed the reaction to be first order in both Mo(N[R]Ar)(3) and N2O, consistent with a mechanism featuring post-rate-determining dinuclear N-N bond scission, but also consistent with cleavage of the N-N bond at a single metal center in a mechanism requiring the intermediacy of nitric oxide. The new 2-adamantyl-substituted molybdenum complex Mo(N[2-Ad]Ar)(3) was synthesized and found also to split N2O, resulting in a 1:1 mixture of nitrosyl and nitride products;,the reaction exhibited first-order kinetics and was found to be ca. 6 times slower than that for the tert-butyl-substituted derivative. Discussed in conjunction with studies of the 2-adamantyl derivative Mo(N[2-Ad]Ar)(3) is the role of ligand-imposed steric constraints on small-molecule, e.g. N-2 and N2O, activation reactivity. Bradley's chromium complex Cr((NPr2)-Pr-i)(3) was found to be competitive with Mo(N[R]Ar)(3) for NO binding, while on its own exhibiting no reaction with N2O. Competition experiments permitted determination of ratios of second-order rate constants for NO binding by the two molybdenum complexes and the chromium complex. Analysis of the product mixtures resulting from carrying out the N2O cleavage reactions with Cr((NPr2)-Pr-i)(3) present as an in situ NO scavenger rules out as dominant any mechanism involving the intermediacy of NO. Simplest and consistent with all the available data is a post-rate-determining bimetallic N-N scission process. Kinetic funneling of the reaction as indicated is taken to be governed by the properties of nitrous oxide as a ligand, coupled with the azophilic nature of three-coordinate molybdenum(III) complexes.

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Olefin metathesis-active ruthenium complexes bearing a nucleophilic carbene ligand

The reaction of [Cp*RuCl](4) (1, Cp* = eta(5)-C5Me5) with the carbene ligand 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes) affords a coordinatively unsaturated Cp*Ru(IMes)Cl (3) complex in 86% isolated yield. Solution calorimetric results in this system provide information concerning the electron donor properties of the carbene ligand, which are very similar to those of PCy3. Structural information from single-crystal X-ray studies for complex 3 allows the determination of steric parameters associated with this ligand. The thermochemical information is used to predict the magnitude of the enthalpic driving force behind substitution reactions involving RuCl2(=C(H)Ph)(PCy3)(2) (1) and the carbene ligand, IMes, affording the RuCl2(=C(H)Ph)(PCy3)(IMes) (6) complex in high yield. A similar mixed carbene/phosphine ruthenium complex, RuCl2(=C(H)Ph)(PPh3)(IMes), can also be isolated from RuCl2(=C(H)Ph)(PPh3)(2) and the IMes ligand. A single-crystal X-ray diffraction study has been performed on 6. The thermal stability of these mixed phosphine/carbene ruthenium carbene complexes has been studied at 60 degrees C in toluene. Their catalytic activity has been evaluated for the ring closing metathesis of diethyldiallylmalonate.

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Four-coordinate molybdenum chalcogenide complexes relevant to nitrous oxide N-N bond cleavage by three-coordinate molybdenum(III) : synthesis, characterization, reactivity, and thermochemistry

The terminal chalcogenide complexes Mo(E)(N[R]Ar)(3) (R = C(CD3)(2)CH3, Ar = 3,5-C6H3Me2), where E = O, S, Se, and Te, were prepared by reaction of the three-coordinate complex Mo(N[R]Ar)(3) with ONC5H5, S-8 or SC2H4, Se, and Te/PEt3 in respective yields of 72, 63, 80, and 73%. The Mo(E)(N[R]Ar)(3) complexes were studied by EPR, SQUID, cyclic voltammetry, 2H NMR spectroscopy, and single-crystal X-ray diffraction. Thermolysis of each Mo(E)(N[R]Ar)(3) complex resulted in (formal) tert-butyl radical elimination giving molybdenum(VI) chalcogenide complexes Mo(E)(NAr)(N[R]Ar)(2) in yields of 85 (E = O), 84 (E = S), 64 (E = Se) and 40% (E = Te). tert-Butyl elimination kinetics were monitored (H-2 NMR) over a 62-104 degrees C temperature range for Mo(O)(N[R]Ar)(3), and from 66 to 93 degrees C for Mo(S)(N[R]Ar)(3); in both cases, a first-order decay was observed. Treatment of Mo(O)(N[R]Ar)(3) with iodine (0.5 equiv) provided [Mo(O)(N[R]Ar)(3)][I] in 88% yield. The triflate salt [Mo(O)(N[R]Ar)(3)][O3SCF3] was prepared similarly (71% yield) upon treatment of Mo(O)(N[R]Ar)(3) with [Cp2Fe][O3SCF3]. Small-scale experiments monitored by H-1 NMR spectroscopy established that Mo(N[R]Ar)(3) deoxygenates OSMe2, NO2, and SO2 but fails to deoxygenate CO2. Also essentially inert to Mo(N[R]Ar)(3) were found to be OPPh3, t-BuNCO, and O2SMe2. Treatment of Mo(N[R]Ar)(3) with Se2Ph2 provided Mo(SePh)(N[R]Ar)(3) in 72% yield. Treatment of Mo(N[R]Ar)(3) with CS2 led to Mo- (S)(N[R]Ar)(3) and (mu-CS)[Mo(N[R]Ar)(3)](2); the latter was isolated in 42% yield and was the subject of an X-ray diffraction study. Bond dissociation enthalpies D(MoE) for Mo(E)(N[R]Ar)(3) (E = O and S) were experimentally determined to be 155.6 +/- 1.6 and 104.4 +/- 1.2 kcal mol(-1), respectively. MoE bond lengths predicted by density functional B3LYP calculations (lanl2dz + d(E) basis set) for the model complexes Mo(E)(NH2)(3) (E = O, S, Se, and Te) were found to compare favorably with the experimentally determined MoE bond lengths. Predicted bond dissociation enthalpies D(MoE) for the hypothetical complexes Mo(E)(NH2)(3) are 91 (E = Se) and 71 (E = Te) kcal mol(-1). A key finding is that Mo(N[R]Ar)(3) selectively splits the nitrous oxide N-N bond to give Mo(N)(NIR]Ar)(3) and Mo(NO)(N[R]Ar)(3), despite the fact that the oxo complex Mo(O)(N[R]Ar)(3) possesses a very strong Mo-O bond and can be prepared by an alternate route.

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Efficient cross-coupling of aryl chlorides with aryl Grignard reagents (Kumada reaction) mediated by a palladium/imidazolium chloride system

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Thermodynamics of addition of H-2, CO, N-2, and C-H bonds to M((PPr3)-Pr-i)(2)Cl (M = Ir, Rh) : an unprecedented metal-carbonyl bond strength

The thermodynamics of interconversion of various complexes containing the unit IrL*Cl-2 (L* = P(Pr-i)(3)) have been investigated by calorimetry and equilibrium measurements. These complexes span a wide range of configurations including four- and five-coordinate d(8) (IrL*2ClL', IrL*Cl-2(CO)(2)) and five- and six-coordinate d(6) (IrL*2ClRH and IrL*2ClRH(CO)). On the basis of kinetic experiments, a lower limit to the Ir-Nz bond dissociation enthalpy (BDE) of IrL*Cl-2(N-2) has been determined (36 kcal/mol). Using this value as an "anchor", in conjunction with the relative addition enthalpies obtained calorimetrically, it is possible to derive lower limits for the absolute exothermicities of H-2 (48 kcal/mol) and CO (72 kcal/mol) addition to IrL*Cl-2; estimates can also be made for the addition of benzene and acetylene C-H bonds. These values are unusually high; indeed, the magnitude of the Ir-CO BDE is unprecedented. In addition, kinetic methods have been used to determine a lower limit of 29 kcal/mol to the Rh-N-2 BDE of RhL*Cl-2(N-2). Combined with previous calorimetric measurements on rhodium complexes, this value permits the calculation of lower limits to the absolute exothermicities of addition to RhL*Cl-2 for numerous small molecules including H-2, CO, N-2, C2H4, and aldehydic C-H bonds. The results of electronic structure calculations (approximate DFT; PMe3 used to model (PPr3)-Pr-i) are in excellent agreement with the relative experimental enthalpies, while the absolute values calculated for addition to IrL2Cl are significantly greater than the experimentally determined lower limits. Addition of a methane C-H bond is calculated to be significantly less favorable than addition of benzene or acetylene C-H bonds, in accord with the fact that IrL*Cl-2(alkyl)H complexes have not been reported. The significant differences in the enthalpies of addition for these three types of C-H bonds are briefly analyzed.

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Thermodynamics of phosphine coordination to the [PNP]Rh-I fragment : an example of the importance of reorganization energies in the assessment of metal-ligand 'Bond Strengths'

Reaction enthalpies of the complexes [RPNP]Rh(COE) ([RPNP] = N(SiMe2CH2PPh2)(2), N(SiMe2-(CH2PPr2)-Pr-i)(2); COE = cyclooctene) with a series of phosphine ligands and CO have been measured by solution calorimetry. The measured enthalpies span range of ca. 40 kcal/mol. These systems favor coordination of strong pi-acceptor/weak sigma-donor ligands as shown by the trend in Delta H-rxn: CO much greater than Ppyrl(3)' > Ppyrl(3) > PPhpyrl(2) > PPh(2)pyrl > PPh3. This trend is exactly the opposite of that observed in another square planar rhodium(I); system, trans-RhCl(CO)(PZ(3))(2). With the exception of CO, the ligands investigated are isosteric, and so the observed trends are electronic in nature. Single-crystal X-ray diffraction studies on several of theses complexes ([RPNP]RhL where R, L = Ph, PPh3; Ph, Ppyrl(3); Ph, CO; Pr-i, PPh3; Pr-i, Ppyrl(3); Pr-i, CO; Pr-i, COE) have been performed. Although the structural trends are readily understood in:terms of the electronic (donor/acceptor) nature of each ligand array, it is not obvious that the structural data predict the trends or, in particular, the trend reversal in Delta H-rxn in the two Rh(I) systems. Rather, these results illustrate the importance of reorganization energies in thermodynamic analyses of metal-ligand bonding, especially in the presence of synergistic bonding involving sigma-donor, pi-donor, and pi-acceptor ligands, interacting through shared metal orbitals (electron push-pull). In such cases the interpretation of a metal-ligand bond dissociation enthalpy (D) as an intrinsic, universal, and transferable property of that bond (e.g., a ''bond strength") is an invalid proposition.

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α2,6-Sialylation mediates hepatocellular carcinoma growth in vitro and in vivo by targeting the Wnt/β-catenin pathway

α2,6-Sialylation mediates hepatocellular carcinoma growth in vitro and in vivo by targeting the Wnt/β-catenin pathway

Oncogenesis 6, e343 (May 2017). doi:10.1038/oncsis.2017.40

Authors: Y Zhao, A Wei, H Zhang, X Chen, L Wang, H Zhang, X Yu, Q Yuan, J Zhang & S Wang

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The immunosuppressive cytokine interleukin-4 increases the clonogenic potential of prostate stem-like cells by activation of STAT6 signalling

The immunosuppressive cytokine interleukin-4 increases the clonogenic potential of prostate stem-like cells by activation of STAT6 signalling

Oncogenesis 6, e342 (May 2017). doi:10.1038/oncsis.2017.23

Authors: G Nappo, F Handle, F R Santer, R V McNeill, R I Seed, A T Collins, G Morrone, Z Culig, N J Maitland & H H H Erb

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Prostate cancer incidence as an iceberg

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Association between childhood adversity and a diagnosis of personality disorder in young adulthood: a cohort study of 107,287 individuals in Stockholm County

Abstract

Childhood adversity (CA) may increase the risk for later developing of personality disorder (PD). However, less is known about the association between cumulative CA and PD, and the role of childhood psychopathology and school performance. The current study examined the relationship between a range of CAs and a diagnosis of PD in young adulthood, and the roles of childhood psychopathology and school performance in this relationship. All individuals born in Stockholm County 1987–1991 (n = 107,287) constituted our cohort. Seven CAs were measured between birth and age 14: familial death, parental criminality, parental substance abuse and psychiatric morbidity, parental separation and/or single-parent household, household public assistance and residential instability. Individuals were followed from their 18th birthday until they were diagnosed with PD or until end of follow-up (December 31st 2011). Adjusted estimates of risk of PD were calculated as hazard ratios (HR) with 95% confidence intervals (CI). Associations were observed between cumulative CA and PD. During the follow-up 770 individuals (0.7%) were diagnosed with PD. Individuals exposed to 3+ CAs had the highest risks of being diagnosed with PD (HR 3.0, 95% CI 2.4–3.7). Childhood psychopathology and low school grades further increased the risk of PD among individuals exposed to CA. Cumulative CA is strongly associated with a diagnosis of PD in young adulthood. Our findings indicate that special attention should be given in schools and health services to children exposed to adversities to prevent decline in school performance, and to detect vulnerable individuals that may be on negative life-course trajectories.

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The hidden epidemic of schistosomiasis in recent African immigrants and asylum seekers to Italy

Abstract

The prevalence of schistosomiasis among recent refugees from sub-Saharan Africa in Italy is unknown. This is a retrospective review of African immigrants screened at Centre for Tropical Diseases of Negrar from March 2014 to February 2016. Of the 373 immigrants tested, 34% were positive at least at one schistosomiasis test. The proportion of positive ELISA serology was 103/373 (27.6%). At microscopy, infected subjects were 65/373 (17.4%), (51% Schistosoma haematobium, 38% Schistosoma mansoni, 11% both). CCA antigen for S. mansoni was positive in 47/373 individuals (12.6%). We found a particularly high positivity rate in subjects from Mali (72.1%) and Ivory Coast (48%). This "hidden epidemic" of schistosomiasis cannot be longer neglected, considering the risk of severe complications, and the effective and inexpensive treatment available.

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Post San Antonio Breast Cancer Symposium

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Morphological control of self-assembled multivalent (SAMul) heparin binding in highly competitive media

Chem. Commun., 2017, Advance Article
DOI: 10.1039/C7CC02990J, Communication

Ana C. Rodrigo, Stephen M. Bromfield, Erik Laurini, Paola Posocco, Sabrina Pricl, David K. Smith
Shape control - self-assembly of ligands into different morphologies directs their ability to bind heparin.
To cite this article before page numbers are assigned, use the DOI form of citation above.
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Crosslinked shells for nano-assembled capsules: a new encapsulation method for smaller Gd3+-loaded capsules with exceedingly high relaxivities

Chem. Commun., 2017, Advance Article
DOI: 10.1039/C7CC00123A, Communication

Annah Farashishiko, Sally E. Plush, Karley B. Maier, A. Dean Sherry, Mark Woods
Nano-capsules with robust, covalently bound, crosslinked shells can be used to encapsulate large payloads of MRI contrast agent, such as GdDOTP^5-, that exhibit very high per-Gd³⁺ relaxivities.
To cite this article before page numbers are assigned, use the DOI form of citation above.
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Lewis acid catalyzed cascade annulation of alkynols with [small alpha]-ketoesters: A facile access to [gamma]-spiroketal-[gamma]-lactones

Chem. Commun., 2017, Accepted Manuscript
DOI: 10.1039/C7CC03668J, Communication

Ravindar Kontham, Digambar Abasaheb Kambale, Sagar Sudam Thorat, Madhukar Shivaji Pratapure, Rajesh G. Gonnade
A novel Lewis acid catalyzed intermolecular cascade annulation of alkynols with [small alpha]-ketoesters has been developed. This simple and efficient cascade annulation proceeds through a 5-exo-dig cyclization of alkynols followed by...
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Observing the Dynamic "Hot Spots" on Two Dimensional Au Nanoparticles Monolayer Film

Chem. Commun., 2017, Accepted Manuscript
DOI: 10.1039/C7CC03020G, Communication

Chenjie Zhang, En-Ming You, Qi Jin, Yaxian Yuan, Minmin Xu, Song-Yuan Ding, Jianlin Yao, Zhong-qun Tian
The interparticle spacing was controlled by evaporation of water on 2D Au nanoparticles arrays. The relationship among SERS effect, SPR catalysis and gap distance have been experimentally and theoretically studied....
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Role of apoptosis in the development of autosomal dominant polycystic kidney disease (ADPKD)

Abstract

Autosomal dominant polycystic kidney disease (ADPKD) is a widespread genetic disorder in the Western world and is characterized by cystogenesis that often leads to end-stage renal disease (ESRD). Mutations in the pkd1 gene, encoding for polycystin-1 (PC1) and its interaction partner pkd2, encoding for polycystin-2 (PC2), are the main drivers of this disease. PC1 and PC2 form a multiprotein membrane complex at cilia sites of the plasma membrane and at intracellular membranes. This complex mediates calcium influx and stimulates various signaling pathways regulating cell survival, proliferation and differentiation. The molecular consequences of pkd1 and pkd2 mutations are still a matter of debate. In particular, the ways in which the cysts are initially formed and progress throughout the disease are unknown. The mechanisms proposed to play a role include enhanced cell proliferation, increased apoptotic cell death and diminished autophagy. In this review, we summarize our current understanding about the contribution of apoptosis to cystogenesis and ADPKD. We present the animal models and the tools and methods that have been created to analyze this process. We also critically review the data that are in favor or against the involvement of apoptosis in disease generation. We argue that apoptosis is probably not the sole driver of cystogenesis but that a cooperative action of cell death, compensatory cell proliferation and perturbed autophagy gradually establish the disease. Finally, we propose novel strategies for uncovering the mode of action of PC1 and PC2 and suggest means by which their dysfunction or loss of expression lead to cystogenesis and ADPKD development.

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Extrarenal determinants of kidney filter function

Abstract

The kidney is an organ involved in cross talk with many human organs. The link between the immune system and the kidney has been studied in some detail, although data precisely elucidating their interaction are sparse, in particular with regard to the function of the kidney filter apparatus. Current research suggests that an understanding of the impairment of this cross talk between the bone marrow, as a fundament of the immune system and the kidney will provide meaningful insights into the pathophysiological mechanisms of impaired kidney filter function. Circulating factors have long been implicated in the pathogenesis of idiopathic nephrotic syndrome, particularly focal segmental glomerulosclerosis (FSGS) and its recurrence. Soluble urokinase receptor (suPAR) has emerged as a circulating factor responsible for FSGS and also as an early predictive marker for the development of various renal diseases. The bone marrow has recently been revealed as a predominant source of suPAR with deleterious effects on the kidney filter. These new findings have led to bone marrow or hematopoietic stem cell transplants being considered as potential therapeutic options for preventing the post-transplantation recurrence of FSGS or even as a treatment for the original disease associated with high suPAR levels. Whereas bone marrow transplantation for patients with pre-existing chronic kidney disease is challenging, recent clinical trials have demonstrated the promising outcome of combined bone marrow and kidney transplantation in patients with kidney failure. In this review, with its brief update on suPAR, we describe the critical new role of the bone marrow in the pathogenesis of the kidney disease process and the functional connection between these two organs through the soluble mediator, suPAR. We also comment on the feasibility of bone marrow transplants for the treatment of patients with chronic renal failure arising from recurrent FSGS.

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Quantifying podocyte depletion: theoretical and practical considerations

Abstract

Podocyte depletion is a central event in the pathogenesis of many glomerular diseases. For this reason, methods to quantify podocyte depletion have become increasingly important. Here, we review currently available methods for quantifying podocyte depletion, including the analysis of glomerular cross-sections, the most important and common stereological methods and newer techniques such as whole glomerular analysis in optically cleared samples. Each method has advantages and limitations. We therefore discuss theoretical and practical considerations to assist the selection of the most appropriate method for an individual study.

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Role of TGF-β in metastatic colon cancer: it is finally time for targeted therapy

Abstract

Colorectal cancer (CRC) is one of the most frequent tumor types in Western countries. Approximately 20 % of patients show metastasis at the time of diagnosis, with the liver being one of the most affected organs. Transforming growth factor-beta (TGF-β) plays a regulatory role not only in the physiology of the normal colon but also in the development of CRC and its metastatic process. In this review, we analyze the molecular mechanisms leading to TGF-β dysregulation in tumor and stroma cells and the modification of the microenvironment that fosters CRC metastasis. Recent genomic studies have identified a CRC subtype with a mesenchymal and aggressive phenotype having TGF-β as a hub gene of this signature. Consistent with these findings, the inhibition of TGF-β signaling has been shown to impair experimental CRC metastasis to the liver. Based on these and other results conducted in various tumor types, the pharmaceutical industry has developed a variety of strategies to target TGF-β. We provide up-to-date information of these therapies, which are currently in preclinical or clinical trials.

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Engineering kidney cells: reprogramming and directed differentiation to renal tissues

Abstract

Growing knowledge of how cell identity is determined at the molecular level has enabled the generation of diverse tissue types, including renal cells from pluripotent or somatic cells. Recently, several in vitro protocols involving either directed differentiation or transcription-factor-based reprogramming to kidney cells have been established. Embryonic stem cells or induced pluripotent stem cells can be guided towards a kidney fate by exposing them to combinations of growth factors or small molecules. Here, renal development is recapitulated in vitro resulting in kidney cells or organoids that show striking similarities to mammalian embryonic nephrons. In addition, culture conditions are also defined that allow the expansion of renal progenitor cells in vitro. Another route towards the generation of kidney cells is direct reprogramming. Key transcription factors are used to directly impose renal cell identity on somatic cells, thus circumventing the pluripotent stage. This complementary approach to stem-cell-based differentiation has been demonstrated to generate renal tubule cells and nephron progenitors. In-vitro-generated renal cells offer new opportunities for modelling inherited and acquired renal diseases on a patient-specific genetic background. These cells represent a potential source for developing novel models for kidney diseases, drug screening and nephrotoxicity testing and might represent the first steps towards kidney cell replacement therapies. In this review, we summarize current approaches for the generation of renal cells in vitro and discuss the advantages of each approach and their potential applications.

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A Dissimilar Biosimilar?: Lichenoid Drug Eruption Induced by an Infliximab Biosimilar

The advent of therapeutic antibodies, or biologic medications, has transformed our treatment of many inflammatory diseases in dermatology. Recently, the development of biosimilars, biologic drugs that are highly similar in quality, safety, and efficacy to approved biologics, has changed this landscape. Although biosimilars are not identical to their reference product, they are required to have the same mechanism of action, route of administration, dosage form, and strength as the reference product. This also leads to the possibility that subtle differences in the activity of these biosimilars can lead to differing clinical responses. We report the first case of a lichenoid eruption induced by a biosimilar to Infliximab after switching from infliximab. Several days after her initial infusion of the biosimilar, the patient developed a pruritic papulosquamous eruption that was biopsied to reveal a lichenoid drug eruption. Possible mechanisms for lichenoid drug eruptions as a result of TNF-alpha inhibitor administration are discussed, along with reasons why such a reaction may occur with a biosimilar but not the original, reference product. This case report calls attention to the unique differences between biosimilars and biologic medications that a clinician should consider prior to prescribing these medications.

This article is protected by copyright. All rights reserved.

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"Anticancer Res"[jour]; +75 new citations

75 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results:

"Anticancer Res"[jour]

These pubmed results were generated on 2017/05/30

PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

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Thermodynamics of addition of CO, isocyanide, and H2 to Rh(PR3)2Cl

The enthalpies of the addition of CO, H-2, or Bu(f)NC to [Rh((PPr3)-Pr-i)(2)Cl](2) (1) to give the mononuclear complexes Rh((PPr3)-Pr-i)(2)Cl(CO) (2), Rh((PPr3)-Pr-i)(2)ClH2 (3), and Rh((PPr3)-Pr-i)(2)Cl(CNBu(t)) (4) are reported. 2-Ethylhexanal is decarbonylated by 1 to give n-heptane and 2; solution-phase calorimetric measurement of this reaction enables calculation of the enthalpy of addition of CO to 1. The coordinatively unsaturated dihydride 3 reacts with Bu(t)NC to give 4; measurement of the enthalpy of this reaction, and the direct reaction of 1 with Bu(t)NC, permits calculation of the enthalpy of addition of H-2 to 1. These results afford the relative enthalpies of addition to the hypothetical fragment Rh((PPr3)-Pr-i)(2)Cl. Although 1 was previously formulated as monomeric in solution, the complex is exclusively dimeric. Based on the observation that no measurable concentration of Rh((PPr3)-Pr-i)(2)Cl monomer exists in solution, a lower limit for the bridge strength of 1 is calculated which, in turn, affords lower limits for the exothermicity of additions to the hypothetical monomer: 48.2 kcal/mol for addition of CO (i.e, the Rh-CO BDE of 1), 42.4 kcal/mol for addition of Bu(t)NC, and 32.5 kcal/mol for addition of H-2. Although these values represent lower limits, the Rh-CO BDE and particularly the exothermicity of H-2 addition are quite high compared with previously reported values for second-row transition metals. These results are consistent with and help to explain the unusual ability of Rh(PMe(3))(2)Cl(CO) to efficiently catalyze photo- and thermochemical alkane functionalization reactions.

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Oncologic safety of cervical nerve preservation in neck dissection for head and neck cancer

Abstract

Background

Although the functional merits of preserving cervical nerves in neck dissection for head and neck cancer have been reported, the oncologic safety has not yet been determined. Therefore, the purpose of this study was to evaluate the safety of cervical nerve preservation.

Methods

A retrospective chart review was performed on patients with head and neck cancer who had been treated by neck dissection between 2009 and 2014 at Kyoto Medical Center. Management of cervical nerves and clinical results were analyzed.

Results

A total of 335 sides of neck dissection had been performed in 222 patients. Cervical nerves were preserved in 175 neck sides and resected in 160 sides. The 5-year overall survival (OS) rate calculated by the Kaplan-Meier method was 71%. The 5-year neck control rate was 95% in cervical nerve preserved sides and 89% in cervical nerve resected sides.

Conclusion

Preserving cervical nerves in neck dissection is oncologically safe in selected cases.

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Corrigendum to “Differences in Brain Metabolic Impairment between Chronic Mild/Moderate TBI Patients with and without Visible Brain Lesions Based on MRI”

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First transition metal-boryl bond energy and quantitation of large differences in sequential bond dissociation energies of boranes

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New Metamaterial Helps Improve High Field MRI Scans

Scientists from Leiden University in The Netherlands and ITMO University in Moscow, Russia have developed a new material that improves the image quality of high-field MRI scanners. The material can be used along with existing MRI coil arrays, as it's flexible and is not very thick, and so can be integrated near the coils.

The material consists of a two-dimensional "metamaterial" of resonant copper strips, and a dielectric substrate stuck to the strip array.

Using a 7 Tesla scanner, which is considerably more powerful than what is widely used in clinical practice today (3T max), they were able to obtain neurological images of higher quality than when not using the new material. Moreover, in addition to being able to acquire better scans, the material may help speed up scans, a major bottleneck in a lot of countries.

"We placed such a metasurface under the patient's head, which increased local sensitivity by 50%. This allowed us to obtain detailed scans of the occipital cortex in half the usual time. Such devices could potentially reduce the duration of MRI studies and improve its comfort for subjects", in a published statement said Rita Schmidt, the leading author of the paper and researcher at the Department of Radiology of Leiden University Medical Center.

Study in journal Scientific Reports: Flexible and compact hybrid metasurfaces for enhanced ultra high field in vivo magnetic resonance imaging…

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Altered postcapillary and collecting venular reactivity in skeletal muscle with metabolic syndrome

Abstract

While research into vascular outcomes of the metabolic syndrome has focused on arterial/arteriolar and capillary levels, investigation into venular function and how this impacts responses has received little attention. Using the in situ cremaster muscle of obese Zucker rats (OZR; with leans (LZR) as controls), we determined indices of venular function. At ∼17 weeks of age, skeletal muscle post-capillary venular density was reduced by ∼20% in LZR vs. OZR, although there was no evidence of remodeling of the venular wall. Venular tone at ∼25 μm (post-capillary) and ∼75 μm (collecting) diameter was elevated in OZR vs. LZR. Venular dilation to acetylcholine was blunted in OZR vs. LZR due to increased oxidant stress-based loss of nitric oxide bioavailability (post-capillary) and increased α₁- (and α₂-) mediated constrictor tone (collecting). Venular constrictor responses in OZR were comparable to LZR for most stimuli, although constriction to α₁ adrenoreceptor stimulation was elevated. In response to field stimulation of the cremaster muscle (0.5, 1, 3 Hz), venular dilator and hyperemic responses to lower frequencies were blunted in OZR, but responses at 3 Hz were similar between strains. Venous production of TxA₂ was higher in OZR than LZR and significantly higher than PGI₂ production in either following arachidonic acid challenge. These results suggest that multi-faceted alterations to skeletal muscle venular function in OZR may contribute to alterations in upstream capillary pressure profiles and the trans-capillary exchange of solutes and water under conditions of metabolic syndrome.

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Spectroscopic detection of organolanthanide dihydrogen and olefin complexes

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The Response of Macro- and Micronutrient Nutrient Status and Biochemical Processes in Rats Fed on a Diet with Selenium-Enriched Defatted Rapeseed and/or Vitamin E Supplementation

The response of nutrient status and biochemical processes in (i) Wistar and (ii) spontaneously hypertensive (SHR) rats upon dietary intake of selenium- (Se-) enriched defatted rapeseed (DRS) and/or vitamin E fortification was examined to assess the health benefit of DRS in animal nutrition. Twenty-four individuals of each type of rat were used: The control group was fed with an untreated diet (Diet A). In Diets B and C, soybean meal was replaced with defatted DRS, which comprised 14% of the total diet. The selenized DRS application resulted in ~3-fold increase of Se content in the diet. Diet C was also fortified with the addition of vitamin E, increasing the natural content by 30%. The Se content of the blood and kidneys tended to increase in the DRS groups, where the changes were significant () only in the case of SHR rats. The iodine (I) content and the proportion of iodide in rat livers indicated a lower transformation rate of iodide into organoiodine compounds compared to the control. Slight and ambiguous alterations in the antioxidative response of the rat were observed in the DRS groups, but the addition of vitamin E to the diet helped to moderate these effects.

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Corrigendum to "Is there a correlation between nasal septum deviation and maxillary transversal deficiency? A retrospective study on prepubertal subjects" [Int. J. Pediatr. Otorhinolaryngol. 83 (April 2016) 109-112].

Related Articles

Corrigendum to "Is there a correlation between nasal septum deviation and maxillary transversal deficiency? A retrospective study on prepubertal subjects" [Int. J. Pediatr. Otorhinolaryngol. 83 (April 2016) 109-112].

Int J Pediatr Otorhinolaryngol. 2016 Nov 21;:

Authors: Ballanti F, Baldini A, Ranieri S, Nota A, Cozza P

PMID: 28551297 [PubMed - as supplied by publisher]

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Evolving trends in head and neck cancer epidemiology: Ontario, Canada 1993-2010

Abstract

Background

Given the dramatic changes in global head and neck cancer epidemiology, the purpose of this study was to present the findings of our investigation on patterns of head and neck cancer incidence/survival within the province of Ontario, Canada.

Methods

Temporal variations in age/sex adjusted incidence and survival were analyzed for all incident head and neck cancer cases (n = 20 781) managed within Ontario from 1993-2010.

Results

From 1993-2010, the incidence of oropharyngeal (average annual percentage change [AAPC] 4.56%; P < .001) and salivary gland (AAPC 4.99%; P < .001) carcinomas increased, whereas oral cavity (AAPC -1.44%; P < .001) and laryngeal/hypopharyngeal (AAPC -3.20%; P < .001) carcinomas declined, and nasopharyngeal carcinoma (NPC) remained static (AAPC 0.28%; P = .72). A general trend for improved 5-year overall survival (OS), was observed for all tumor sites.

Conclusion

Consistent with previous studies, our results suggest a simultaneous decline in tobacco-associated and increase in human papillomavirus (HPV)-mediated carcinomas. The rising incidence of salivary malignancy and improvement in 5-year OS are novel findings, in need of future investigation.

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Salvage surgery for oropharyngeal squamous cell carcinomas: a retrospective study from 2005 to 2013

Abstract

Background

In the case of a locoregional recurrence of oropharyngeal squamous cell carcinoma, the curative standard of care is surgery. Our main purpose of this study was to determine the preoperative prognostic factors that would allow us to select the patients on whom we could expect good results with salvage surgery.

Methods

We conducted a monocentric retrospective study from 2005 to 2013. It included all patients treated for a recurrence of oropharyngeal squamous cell carcinoma with surgery. Their initial treatment included radiotherapy.

Results

Fifty-two patients were included. Poor prognostic factors for survival were the cT status (P = .0039) and local recurrences versus secondary localizations in irradiated areas (P = .016) and a relapse less than a year after the end of the initial treatment (P = .050). Recurrence-free survival was 19% at 5 years. Twenty-nine percent of patients presented local complications, which were mainly fistulas and hemorrhaging at the surgical site.

Conclusion

According to the high morbimortality, it is important to carefully select the right patients for surgery.

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A numerical kinematic model of welding process for low carbon steels

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Heat girdling does not affect xylem integrity: an in vivo magnetic resonance imaging study in the tomato peduncle

Heat girdling is a method to estimate the relative contribution of phloem vs xylem water flow to fruit growth. The heat girdling process is assumed to destroy all living tissues, including the phloem, without affecting xylem conductivity. However, to date, the assumption that xylem is not affected by heat girdling remains unproven. In this study, we used in vivo magnetic resonance imaging (MRI) velocimetry to test if heat girdling can cause xylem vessels to embolize or affect xylem water flow characteristics in the peduncle of tomato (Solanum lycopersicum cv Dirk). Anatomical and MRI data indicated that, at the site of girdling, all living tissues were disrupted, but that the functionality of the xylem remained unchanged. MRI velocimetry showed that the volume flow through the secondary xylem was not impeded by heat girdling in either the short or the long term (up to 91 h after girdling). This study provides support for the hypothesis that in the tomato peduncle the integrity and functionality of the xylem remain unaffected by heat girdling. It therefore confirms the validity of the heat girdling technique as a means to estimate relative contributions of xylem and phloem water flow to fruit growth.

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Relationship between non-standard work arrangements and work-related accident absence in Belgium

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Cosine based and extended transmissibility damage indicators for structural damage detection

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Numerical prediction of fretting fatigue crack trajectory in a railway axle using XFEM

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Form- finding analysis of suspension bridges using an explicit Iterative approach

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A Dissimilar Biosimilar?: Lichenoid Drug Eruption Induced by an Infliximab Biosimilar

The advent of therapeutic antibodies, or biologic medications, has transformed our treatment of many inflammatory diseases in dermatology. Recently, the development of biosimilars, biologic drugs that are highly similar in quality, safety, and efficacy to approved biologics, has changed this landscape. Although biosimilars are not identical to their reference product, they are required to have the same mechanism of action, route of administration, dosage form, and strength as the reference product. This also leads to the possibility that subtle differences in the activity of these biosimilars can lead to differing clinical responses. We report the first case of a lichenoid eruption induced by a biosimilar to Infliximab after switching from infliximab. Several days after her initial infusion of the biosimilar, the patient developed a pruritic papulosquamous eruption that was biopsied to reveal a lichenoid drug eruption. Possible mechanisms for lichenoid drug eruptions as a result of TNF-alpha inhibitor administration are discussed, along with reasons why such a reaction may occur with a biosimilar but not the original, reference product. This case report calls attention to the unique differences between biosimilars and biologic medications that a clinician should consider prior to prescribing these medications.

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Thermodynamics of addition of CO, isocyanide, and H2 to Rh(PR3)2Cl

The enthalpies of the addition of CO, H-2, or Bu(f)NC to [Rh((PPr3)-Pr-i)(2)Cl](2) (1) to give the mononuclear complexes Rh((PPr3)-Pr-i)(2)Cl(CO) (2), Rh((PPr3)-Pr-i)(2)ClH2 (3), and Rh((PPr3)-Pr-i)(2)Cl(CNBu(t)) (4) are reported. 2-Ethylhexanal is decarbonylated by 1 to give n-heptane and 2; solution-phase calorimetric measurement of this reaction enables calculation of the enthalpy of addition of CO to 1. The coordinatively unsaturated dihydride 3 reacts with Bu(t)NC to give 4; measurement of the enthalpy of this reaction, and the direct reaction of 1 with Bu(t)NC, permits calculation of the enthalpy of addition of H-2 to 1. These results afford the relative enthalpies of addition to the hypothetical fragment Rh((PPr3)-Pr-i)(2)Cl. Although 1 was previously formulated as monomeric in solution, the complex is exclusively dimeric. Based on the observation that no measurable concentration of Rh((PPr3)-Pr-i)(2)Cl monomer exists in solution, a lower limit for the bridge strength of 1 is calculated which, in turn, affords lower limits for the exothermicity of additions to the hypothetical monomer: 48.2 kcal/mol for addition of CO (i.e, the Rh-CO BDE of 1), 42.4 kcal/mol for addition of Bu(t)NC, and 32.5 kcal/mol for addition of H-2. Although these values represent lower limits, the Rh-CO BDE and particularly the exothermicity of H-2 addition are quite high compared with previously reported values for second-row transition metals. These results are consistent with and help to explain the unusual ability of Rh(PMe(3))(2)Cl(CO) to efficiently catalyze photo- and thermochemical alkane functionalization reactions.

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