IS6110-PCR分型方法用于安徽、湖南、江苏三省结核病分子流行病学的初步研究

目的了解安徽、湖南、江苏省结核分支杆菌的基因型状况及其分子流行病学规律。方法以结核分枝杆菌插入序列IS6110序列为模板,设计一对特异外向引物,建立一种结核分枝杆菌的快速分子生物学分型方法——IS6110PCR分型方法,进行三省结核病分子流行病学研究。结果根据IS6110PCR指纹图谱,191株安徽、湖南和江苏三省的结核分枝杆菌菌株可被分成6个主要的基因型(Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ和Ⅵ),江苏省的主要基因型为I和V型,安徽省的主要基因型为III型,湖南省的主要基因型为I和II型,V型菌株全部为江苏省菌株,IV型菌株全部为湖南省菌株。结论三省之间结核分支杆菌的基因型存在明显的差异,各自存在着独立的流行菌型,其真实原因有待进一步研究。     

Impaired regeneration in LGMD2A supported by increased PAX7‐positive satellite cell content and muscle‐specific microrna dysregulation

Introduction: Recent in vitro studies suggest that CAPN3 deficiency leads initially to accelerated myofiber formation followed by depletion of satellite cells (SC). In normal muscle, up‐regulation of miR‐1 and miR‐206 facilitates transition from proliferating SCs to differentiating myogenic progenitors. Methods: We examined the histopathological stages, Pax7 SC content, and muscle‐specific microRNA expression in biopsy specimens from well‐characterized LGMD 2A patients to gain insight into disease pathogenesis. Results: Three distinct stages of pathological changes were identified that represented the continuum of the dystrophic process from prominent inflammation with necrosis and regeneration to prominent fibrosis, which correlated with age and disease duration. Pax7‐positive SCs were highest in the fibrotic group and correlated with down‐regulation of miR‐1, miR‐133a, and miR‐206. Conclusions: These observations, and other published reports, are consistent with microRNA dysregulation leading to inability of Pax7‐positive SCs to transit from proliferation to differentiation. This results in impaired regeneration and fibrosis. Muscle Nerve 47: 731–739, 2013     

The influence of peripheral vascular disease on methanogenesis in man

Methane is produced by anaerobic bacterial metabolism in the colon and is excreted in the breath of only a proportion of healthy adults. Factors influencing methane excretion have still to be elucidated. The colonic vascular circulation may influence the intestinal environment facilitating growth of methanogens. The incidence of breath methane excretion has been investigated in patients with peripheral vascular disease and a control patient group. The proportions of subjects excreting methane in the control hospital group (43%) and in patients with predominantly femoro-popliteal disease (30%) were significantly less than in patients with predominantly aorto-iliac disease (83%) (P less than 0.005 and P less than 0.001, respectively). The presence of abdominal aortic arterial disease appears to be associated with a high incidence of methane excretion.     

Intracranial vessel wall lesions on 7T MRI and MRI features of cerebral small vessel disease: The SMART-MR study

The etiology of cerebral small vessel disease (CSVD) is the subject of ongoing research. Although intracranial atherosclerosis (ICAS) has been proposed as a possible cause, studies on their relationship remain sparse. We used 7 T vessel wall magnetic resonance imaging (MRI) to study the association between intracranial vessel wall lesions—a neuroimaging marker of ICAS—and MRI features of CSVD. Within the SMART-MR study, cross-sectional analyses were performed in 130 patients (68 ± 9 years; 88% male). ICAS burden—defined as the number of vessel wall lesions—was determined on 7 T vessel wall MRI. CSVD features were determined on 1.5 T and 7 T MRI. Associations between ICAS burden and CSVD features were estimated with linear or modified Poisson regression, adjusted for age, sex, vascular risk factors, and medication use. In 125 patients, ≥1 vessel wall lesions were found (mean 8.5 ± 5.7 lesions). ICAS burden (per + 1 SD) was associated with presence of large subcortical and/or cortical infarcts (RR = 1.65; 95%CI: 1.12–2.43), lacunes (RR = 1.45; 95% CI: 1.14–1.86), cortical microinfarcts (RR = 1.48; 95%CI: 1.13–1.94), and total white matter hyperintensity volume (b = 0.24; 95%CI: 0.02–0.46). Concluding, patients with a higher ICAS burden had more CSVD features, although no evidence of co-location was observed. Further longitudinal studies are required to determine if ICAS precedes development of CSVD.     

Effect of ASCO/CAP Guidelines for Determining ER Status on Molecular Subtype

Background

Determination of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status is standard for predicting prognosis and determining treatment options for patients with breast cancer. In 2010, the American Society of Clinical Oncology (ASCO) and College of American Pathologists (CAP) issued guidelines that tumors with ≥1 % positively staining cells should be considered ER positive. Here, we determined how this cutoff relates to molecular subtype.

Methods

Clinicopathological characteristics were compared between ER-negative, ER-positive, and low-ER-staining (1–10 %) tumors using chi-square analysis with P < 0.05 defining statistical significance. Gene expression data were generated for 26 low-ER-staining tumors, and their intrinsic subtype determined. Immunohistochemistry (IHC)-defined surrogate subtypes, using the threshold of positivity defined by ASCO/CAP guidelines, were compared with molecular subtypes.

Results

Low-ER-staining tumors were clinicopathologically more similar to ER-negative than to ER-positive tumors; 88 % of low-staining tumors were basal like or HER2 enriched. Only those tumors expressing 10 % ER-positive cells were classified as luminal A subtype.

Conclusions

Under ASCO/CAP guidelines, tumors with 1–10 % ER staining would be classified as ER positive, yet most are basal like or HER2 enriched and have pathological features similar to ER-negative tumors. Clinical trials seeking to treat tumors of ER-negative basal-like and/or HER2-enriched subtypes should thus not preclude enrollment based solely on results of ER immunohistochemistry. As ER status is a critical element in the choice of treatments for patients with breast cancer, it is imperative that the most effective method for classifying tumors be developed.