A new cascade halosulfonylation of 1,7-enynes toward 3,4-dihydroquinolin-2(1H)-ones via sulfonyl radical-triggered addition/6-exo-dig cyclization

Chem. Commun., 2015, Accepted Manuscript
DOI: 10.1039/C5CC08895J, Communication

Yi-Long Zhu, Bo Jiang, Wen-Juan Hao, Ai-Fang Wang, Jiang-Kai Qiu, Ping Wei, Decai Wang, Guigen Li, Shu-Jiang Tu
A new cascade three-component halosulfonylation of 1,7-enynes for efficient synthesis of densely functionalized 3,4-dihydroquinolin-2(1H)-ones has been established from readily accessible arylsulfonyl hydrazides and NIS (or NBS). The reaction pathway involves...
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Combined treatment of somatostatin analogues with pegvisomant in acromegaly

Abstract

Treatment of acromegaly with monotherapy long-acting somatostatin analogues (LA-SSA) as primary treatment or after neurosurgery can only achieve complete normalization of insulin-like growth factor I (IGF-I) in roughly 40 % of patients. Recently, one of the acromegaly consensus groups has recommended switching to combined treatment of LA-SSA and pegvisomant (PEGV) in patients with partial response to LA-SSAs. This combination of LA-SSA and PEGV, a growth hormone receptor antagonist, can normalize IGF-I levels in virtually all patients, requiring that the adequate dose of PEGV is used. The required PEGV dose varies significantly between individual acromegaly patients. One of the advantages of the combination therapy is that tumor size control or even tumor shrinkage can be observed in a vast majority of patients. The main side effects of the combination treatment are gastrointestinal symptoms, lipohypertrophy and transient elevated liver transaminases. In this review we provide an overview of the efficacy and safety of the combined treatment of LA-SSAs with PEGV.

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IJMS, Vol. 16, Pages 29673-29681: One-Electron Reduction of Penicillins in Relation to the Oxidative Stress Phenomenon

Certain bactericidal antibiotics target mitochondrial components and, due to the leakage of electrons from the electron transport chain, one-electron reduction might occur that can lead to intermediates passing the electron to suitable acceptors. This study aimed at investigating the one-electron reduction mechanism of selected penicillin derivatives using pulse radiolysis techniques. Penicillins can accommodate the electron on each of their carbonyl carbon. Ketyl radicals are thus produced, which are reducing agents with possibility to interact with suitable biomolecules. A detailed mechanism of the reduction is reported.

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Sandwich organization of non-ionic surfactant liquid crystalline phases as induced by large inorganic K4Nb6O17 nanosheets

Chem. Commun., 2016, Advance Article
DOI: 10.1039/C5CC08948D, Communication

R. Guegan, K. Sueyoshi, S. Anraku, S. Yamamoto, N. Miyamoto
While retaining its liquid crystal properties, niobate nanosheets were used to sandwich a lamellar monodomain made up of nonionic surfactants and water.
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Assessment of the stability of exogenous gamma hydroxybutyric acid (GHB) in stored blood and urine specimens

OBJECTIVE: The aim of this work is to test the stability of exogenous GHB in whole blood and urine samples collected from living and deceased GHB free-users, spiked with known concentrations of GHB and stored at different temperatures (–20°C, 4°C and 20°C) up to 4 weeks.

MATERIALS AND METHODS: GHB was added to GHB-free ante-mortem blood and urine samples at the concentration of 5 and 10 mg/L, respectively whereas in post-mortem blood and urine specimens at 50 and 10 mg/L respectively. All samples were stored at three different temperatures: –20°C, 4°C and 20°C and extracted and analyzed at three days, 1 week, 2 weeks, 3 and 4 weeks in duplicate. No preservatives were added. GHB was quantified by GC-MS after LLE according to a previously published method.

RESULTS: Post-mortem blood specimens showed a reduction of GHB levels higher than 10% only after a period of 4 weeks of storage for samples kept at +4°C and +20°C, whereas samples stored at –20°C showed a mean reduction of 8.7%. In post-mortem urine samples, there was a mean reduction of GHB levels higher than 20% at all storage temperatures, after 4 weeks of storage. Ante-mortem blood samples showed a reduction of GHB levels lower than 10% only after 3 days of storage at –20°C and at +4°C (samples stored at +20°C showed a mean reduction of 10.4%). After 4 weeks of storage, there was a mean reduction of GHB concentrations higher than 20% at all storage temperatures. Ante-mortem urine samples showed a reduction of GHB levels higher than 10% after just 3 days of storage for samples kept at all tested temperatures. After 4 weeks of storage, there was a mean reduction of GHB concentrations higher than 25% at all storage temperatures.

CONCLUSIONS: According to our findings, it would be useful to perform GHB analysis both in blood and urine specimens within 3 days of sampling and the specimens should be stored at –20°C or 4°C in order to avoid instability issues.

L'articolo Assessment of the stability of exogenous gamma hydroxybutyric acid (GHB) in stored blood and urine specimens sembra essere il primo su European Review.

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Supporting and assisting the execution of flexible healthcare processes

Business process management has yet to fully conquer the healthcare sector. Although it has proven effective for more static and standardized healthcare processes, it does not offer a definitive answer for the dynamic, flexible and knowledge- intensive processes typically associated with the healthcare sector. Contemporary business process techniques, like imperative business process models (e.g., BPMN), do not allow for the flexibility required by these types of processes. In this paper we propose a new type of tool, a recommendation-based robust business process engine, in an effort to combat this problem. The goal is to not only support a more process-driven approach in healthcare, but also assist the users (i.e., doctors, nurses and other hospital personnel) during these processes. This should result in an improvement of the service levels and add another barrier to prevent doctor errors, without being detrimental to the empowerment of the personnel that characterizes the healthcare sector.

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Towards the understanding of variable amplitude fatigue

Fatigue life estimation is of high importance during the design stage of a machine or component. Basic fatigue calculations are made based on the use of an S-N curve. As far as constant amplitude loads are applied, this approach works well. However, most part of components in service are subjected to a variable amplitude load spectrum. In this case, linear approaches for fatigue life estimation can lead to over conservative results, which in other words means a heavier and more expensive machine. To further investigate the effect of (complex) service spectra (measured or statistically calculated), simpler load variations must be studied. This paper aims to show the general trend of these events and suggest the underlying physical phenomena behind load and interaction effects. As it will be highlighted, overloads are frequent in a spectrum and they are believed to be responsible for retardation effects. The plasticity induced crack closure mechanism is the most profound explanation for them to occur.

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