SciCombinator

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Concept: Polymorphism in object-oriented programming

173

Cholinergic urticaria (CU) has clinically characteristic features, and has been frequently described in the literature. However, despite its comparatively old history, the pathogenesis and classification remains to be clarified. CU patients are occasionally complicated by anhidrosis and/or hypohidrosis. This reduced-sweat type should be included in the classification because the therapeutic approaches are different from the ordinary CU. It is also well-known that autologous sweat is involved in the occurrence of CU. More than half of CU patients may have sweat hypersensitivity. We attempt to classify CU and address the underlying mechanisms of CU based on the published data and our findings. The first step for classification of CU seems to discriminate the presence or absence of hypersensitivity to autologous sweat. The second step is proposed to determine whether the patients can sweat normally or not. With these data, the patients could be categorized into three subtypes: (1) CU with sweat hypersensitivity; (2) CU with acquired anhidrosis and/or hypohidrosis; (3) idiopathic CU. The pathogenesis of each subtype is also discussed in this review.

Concepts: Perspiration, Subtype polymorphism, Polymorphism in object-oriented programming, Type theory, Hyperhidrosis, Cholinergic urticaria, Medical terms

169

The identification and surveillance of patients with preneoplastic lesions at high risk of progressing to gastric cancer (GC) represents the most effective way of reducing the burden of GC. The incomplete type of intestinal metaplasia (IM) could be considered as the best candidate for surveillance. However, the usefulness of subtyping of IM has been considered by some authors as limited and inconsistent. A search was carried out to identify all cross-sectional (n= 14) and follow-up (n= 10) studies that assessed the risk of GC among subjects with different types of IM. Out of the 14 cross-sectional studies, 13 reported that the prevalence of incomplete IM was statistically significantly higher in GC than in other gastric lesions. Out of the 10 follow-up studies, 6 found a statistically significant association between incomplete IM and subsequent GC risk. The relative risks of GC were from 4 to 11-fold higher for the presence of incomplete type in comparison to complete type or in comparison to the absence of incomplete type, among the studies that reported the magnitude of the risk. According to this comprehensive review, most of the scientific evidence supports the utility of subtyping IM as a predictor of GC risk. Recognizing its usefulness by gastroenterologists should encourage pathologists to subtype IM. © 2012 Wiley Periodicals, Inc.

Concepts: Subtype polymorphism, Scientific method, Decision theory, Polymorphism in object-oriented programming, Risk aversion, Epidemiology, First-order logic, Type theory

21

Malignant mesothelioma (MM) has distinct histological subtypes (epithelioid, sarcomatoid and biphasic) with variable behaviour and prognoses. It is well recognised that survival time varies with the histological subtype of MM. It is not known, however, if asbestos exposure characteristics (type of asbestos, degree of exposure) are associated with different histological subtypes.

Concepts: Polymorphism in object-oriented programming, Data types, Wittenoom, Western Australia, Asbestos and the law, Mesothelioma, Type theory, Asbestos, Cancer

7

Electronic and structural detail at the electrode-molecule interface have a significant influence on charge transport across molecular junctions. Despite the decisive role of the metal-molecule interface, a complete electronic and structural characterization of the interface remains a challenge. This is in no small part due to current experimental limitations. Here, we present a comprehensive approach to obtain a detailed description of the metal-molecule interface in single-molecule junctions, based on current-voltage (I-V) measurements. Contrary to conventional conductance studies, this I-V approach provides a correlated statistical description of both, the degree of electronic coupling across the metal-molecule interface, and the energy alignment between the conduction orbital and the Fermi level of the electrode. This exhaustive statistical approach was employed to study single-molecule junctions of 1,4-benzenediamine (BDA), 1,4-butanediamine (C4DA), and 1,4-benzenedithiol (BDT). A single interfacial configuration was observed for both BDA and C4DA junctions, while three different interfacial arrangements were resolved for BDT. This multiplicity is due to different molecular adsorption sites on the Au surface namely on-top, hollow, and bridge. Furthermore, C4DA junctions present a fluctuating I-V curve arising from the greater conformational freedom of the saturated alkyl chain, in sharp contrast with the rigid aromatic backbone of both BDA and BDT.

Concepts: Experiment, Adsorption, Statistics, Polymorphism in object-oriented programming, Object-oriented programming

3

In this study we developed a genome-based method for detecting Staphylococcus aureus subtypes from metagenome shotgun sequence data. We used a binomial mixture model and the coverage counts at >100,000 known S. aureus SNP (single nucleotide polymorphism) sites derived from prior comparative genomic analysis to estimate the proportion of 40 subtypes in metagenome samples. We were able to obtain >87% sensitivity and >94% specificity at 0.025X coverage for S. aureus. We found that 321 and 149 metagenome samples from the Human Microbiome Project and metaSUB analysis of the New York City subway, respectively, contained S. aureus at genome coverage >0.025. In both projects, CC8 and CC30 were the most common S. aureus clonal complexes encountered. We found evidence that the subtype composition at different body sites of the same individual were more similar than random sampling and more limited evidence that certain body sites were enriched for particular subtypes. One surprising finding was the apparent high frequency of CC398, a lineage often associated with livestock, in samples from the tongue dorsum. Epidemiologic analysis of the HMP subject population suggested that high BMI (body mass index) and health insurance are possibly associated with S. aureus carriage but there was limited power to identify factors linked to carriage of even the most common subtype. In the NYC subway data, we found a small signal of geographic distance affecting subtype clustering but other unknown factors influence taxonomic distribution of the species around the city.

Concepts: Genomics, Bioinformatics, Subtype polymorphism, Polymorphism in object-oriented programming, Staphylococcus aureus, Object-oriented programming, New York City, Body mass index

3

Blastocystis species has been extensively studied in recent few years to establish its pathogenecity. Present study was designed to identify and examine the association of Blastocystis sp. and its subtypes with Irritable Bowel Syndrome (IBS).Blastocystis sp. detected using wet-mount microscopy, trichrome staining, in-vitro culture and Polymerase Chain Reaction (PCR) assay in a cohort of IBS patients (n = 150) and healthy controls (n = 100). Isolates of Blastocystis sp.were subtyped using Sequence Tagged Site and representative samples were sequenced at SSUrRNA locus.A total of sixty five isolates of Blastocystis sp. were identified [IBS (n = 50); Controls (n = 15)] of which 91% belonged to ST3 and 9% belonged to ST1. No other subtypes could be identified. Statistically significant association was observed between Blastocystis sp. and IBS patients; however no particular subtype could be ascertained to any particular clinical type of IBS.The frequency of occurrence of Blastocystis sp. was more in IBS patients as compared to the controls and ST3 being the most prevalent subtype. The genetic polymorphism of SSU-rRNA gene amongst the different Blastocystis sp.isolates found in this study reinforces the fact that these organisms are genetically highly divergent.

Concepts: Object-oriented programming, Biology, Molecular biology, Polymorphism in object-oriented programming, Genetics, Polymerase chain reaction, DNA, Irritable bowel syndrome

1

Glecaprevir and pibrentasvir are hepatitis C virus (HCV) pangenotypic inhibitors targeting NS3/4A protease and NS5A, respectively. This once-daily, fixed-dose combination regimen demonstrated high SVR12 rates in CERTAIN-1 and CERTAIN-2 studies in Japanese HCV-infected patients, with a low virologic failure (VF) rate (1.2%). There were no VFs among direct acting antiviral (DAA)-treatment-naive genotype (GT)1a- (n=4), GT1b- (n=128), and GT2- (n=97) infected non-cirrhotic patients treated for 8 weeks, or GT1b- (n=38) or GT2- (n=20) infected patients with compensated cirrhosis treated for 12 weeks. Two of 33 DAA-experienced and 2/12 GT3-infected patients treated for 12 weeks experienced VF. Pooled resistance analysis, grouped by HCV subtype, treatment duration, prior treatment experience, and cirrhosis status was conducted. Among DAA-naïve GT1b-infected patients, the baseline prevalence of NS3-D168E was 1.2%, NS5A-L31M was 3.6%, and NS5A-Y93H was 17.6%. Baseline polymorphisms (BP) in NS3 or NS5A were less prevalent in GT2 with the exception of the common L/M31 polymorphism in NS5A. Among DAA-experienced GT1b-infected patients (30/32 experienced to daclatasvir and asunaprevir), the baseline prevalence of NS3-D168E/T/V was 48.4%, NS5A-L31F/I/M/V was 81.3%, NS5A-P32deletion was 6.3%, and NS5A-Y93H was 59.4%. Common BPs in NS3 and/or NS5A had no impact on treatment outcome in GT1- and GT2-infected patients; the impact in GT3-infected patients could not be assessed due to enrollment of diverse subtypes and limited number of patients. The glecaprevir/pibrentasvir combination regimen allows for a simplified treatment option without the need for HCV subtyping or baseline resistance testing for DAA-naïve GT1 or GT2-infected patients.

Concepts: Hepatitis, Common cold, Circle-ellipse problem, Hepatitis C virus, Object-oriented programming, Subtype polymorphism, Polymorphism in object-oriented programming, Hepatitis C

1

OBJECT Blister aneurysms of the supraclinoid part of the internal carotid artery (ICA) are known for their high morbidity and mortality rates related to treatment, regardless of whether the treatment is surgical or endovascular. However, this grim prognosis is based on results that indiscriminately group all blister aneurysms together without taking into account the heterogeneous appearance of these lesions. The goal of this study was 2-fold: to determine whether different blister aneurysm morphologies present different pitfalls, which would then require different surgical strategies, as well as to determine whether there are identifiable subgroups of these types of aneurysms based on morphology. METHODS The authors reviewed the charts, cerebral catheter angiograms, surgical reports, and intraoperative videos of all ICA blister aneurysms treated surgically at the Centre Hospitalier de l'Université de Montréal from 2005 to 2012 to investigate whether there was a relationship between morphology and pitfalls, and whether different surgical strategies had been used according to these pitfalls. During this review process the authors noted 4 distinct morphological aspects. These 4 aspects led to a review of the English and French literature on blister aneurysms in which imaging was available, to determine whether other cases could also be classified into the same 4 subgroups based on these morphological aspects. RESULTS The retrospective review of the authors' series of 10 patients allowed a division into 4 distinct subtypes: Type I (classic), Type II (berry-like), Type III (longitudinal), and Type IV (circumferential). These subtypes may at times be progressive stages in the arterial anomaly, and could represent a continuum. Each subtype described in this paper presented its own pitfalls and required specific surgical adaptations. Upon reviewing the literature the authors retained 35 studies involving a total of 61 cases of blister aneurysms, and all cases were able to be classified into 1 of these 4 distinct subtypes. CONCLUSIONS Although they share some common characteristics, blister aneurysms may be divided into distinct subtypes, suggestive of a continuum. Such a classification with a detailed description of each type of blister aneurysm would allow for better recognition to anticipate complications during intervention and better assess the different treatment strategies according to the subtypes.

Concepts: Internal jugular vein, Object-oriented programming, Polymorphism in object-oriented programming, External carotid artery, Mortality rate, Internal carotid artery, Atherosclerosis, Common carotid artery

1

BACKGROUND & AIMS:: Patients with achalasia are treated with either pneumatic dilation (PD) or laparoscopic Heller myotomy (LHM), which have comparable rates of success. We evaluated whether manometric subtype was associated with response to treatment in a large population of patients treated with either PD or LHM (the European achalasia trial). METHODS:: Esophageal pre-treatment manometry data were collected from 176 patients who participated in the European achalasia trial. Symptoms (weight loss, dysphagia, retrosternal pain, and regurgitation) were assessed using the Eckardt score; treatment was considered successful if the Eckardt score was =3. Manometric tracings were classified according to the 3 Chicago subtypes. RESULTS:: Forty-four patients had achalasia type I (25%), 114 had type II (65%), and 18 had type III (10%). After a minimum follow-up period of 2 years, success rates were significantly higher among patients with type II achalasia (96%) than type I (81%; P <.01, log-rank test) or type III achalasia (66%; P <.001, log-rank test). The success rate of PD was significantly higher than of LHM for patients with type II achalasia (100% vs 93%; P <.05), but LHM had a higher success rate than PD for patients with type III achalasia (86% vs 40%; P =0.12, difference not statistically significant, because of small number of patients). For type I achalasia, LHM and PD had similar rates of success (81% vs 85%; P =0.84). CONCLUSION:: A higher percentage of patients with type II achalasia (based on manometric tracings) are successfully treated with PD or LHM than patients with types I and III achalasia. More patients with type II achalasia were successfully treated with PD therapy, whereas more with type III are probably best treated with LHM. (trialregister.nl number NTR37; ISRCTN56304564).

Concepts: Statistics, Gastroesophageal reflux disease, Statistical significance, Polymorphism in object-oriented programming, Type I and type II errors, Surgery, Achalasia, Heller myotomy

0

A simple alcohol-soluble perylene derivative (i.e., tetramethyl ammonium salt of perylene-3,4,9,10-tetracarboxylic acid; TMA-PTC) was prepared and applied as a cathode interlayer (CIL) to modify the PC61BM/Ag interface in planar p-i-n perovskite solar cells (PeSCs). As a result, the power conversion efficiency (PCE) of the TMA-PTC-based PeSCs is ca. 30% higher than that of the devices without CIL. It was revealed that the enhancement in PCE might be attributed to the improved electron-transporting and hole-blocking properties of the PC61BM/TMA-PTC/Ag interfaces. Moreover, the TMA-PTC devices show remarkably higher stability than those without CIL probably due to the suppressed corrosion of perovskite on Ag cathode. Our findings thus demonstrate a multifunctional and solution-processable CIL which might be a promising block for the fabrication of low-cost, high efficiency and stable planar p-i-n PeSCs.

Concepts: Polymorphism in object-oriented programming, Object-oriented programming, Ammonia, Energy conversion, Solar cell, Energy conversion efficiency, Diode, Ion