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     

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.     

萘甲异喹对离体豚鼠心肌的作用

萘甲异喹(NI)呈浓度依赖性地降低离体豚鼠心房收缩力和频率。其拮抗豚鼠左房肌Iso正性肌力作用的PD2₂′值为5.4,Ver为5.8。NI10μmol/L明显降低豚鼠乳头肌收缩力;缩短快反应APD,以对APD₂₀影响最大,但不影响APA和V_max。对高K⁺去极化慢反应动作电位,NI产生浓度依赖性负性肌力作用,同时明显降低APA,V_max,缩短APD;提高细胞外液Ca²⁺浓度可使其抑制作用逆转。结果提示NI具有钙通道阻滞作用。     

Volume calculation by means of SPECT: analysis of imaging acquisition and processing factors

To assess the effect of image acquisition and processing factors on the volume calculated from single photon emission computed tomography (SPECT) images, the authors evaluated technical factors including image matrix size, size of the region of interest (ROI), activity concentration in the region, amount of background subtraction, type of reconstruction filter, section thickness, and number of projections. They found that the percentage of background subtraction was the single most important factor affecting volume calculation. The smaller the volume, the greater the amount of background subtraction needed before the ROI is drawn. As an acceptable means to circumvent the varying percentage of background subtraction for different volumes, a calibration curve was constructed relating the true volume with the calculated volume for a fixed percentage of background subtraction. The use of a 128 X 128 acquisition matrix and zooming of the reconstructed images were necessary for accurate calculation of volumes smaller than 300 mL.     

毛梗稀莶抗生育活性成分的研究

自菊科植物毛梗豨莶Siegesbeckia glabrescens Mak的全草中分得一个新的二萜甙,命名为豨莶新甙(neodarutoside),经光谱(IR,¹ HNMR,¹³ CNMR和MS)分析,确定结构为(I);同时分得的二萜有豨莶精醇(darutigenol,Ⅳ)和豨莶甙(d&rutoside,Ⅴ)。豨莶甙(Ⅴ)在20～40 mg/kg剂量时,对大鼠有明显抗早孕作用。     

测定咖啡因代谢物评价 N-乙酰转移酶、CYP1A2和黄嘌呤氧化酶活性

目的是对中国人N-乙酰化酶(NAT2)、CYP1A2酶和黄嘌呤氧化酶(XO)的活性进行分析。120名健康志愿者饮用3杯咖啡后于4～5h留尿,用HPLC方法测定尿中5种咖啡因主要代谢物浓度,即5-乙酰胺基-6-甲酰胺基-3-甲基尿嘧啶(AFMU)、1-甲基黄嘌呤(1X)、1-甲基尿酸(1U)、1,7-二甲基尿酸(17X)、1,7-二甲基黄嘌呤(17U)。其中N-乙酰化酶活性用AFMU/1X或AFMU/(AFMU+1X+1U)表示;CYP1A2酶活性指标采用(AFMU+1X+1U)/17X或AFMU+1X+1U)/17U;XO酶活性指标采用1U/1X或1U/(1X+1U)。结果表明,N-乙酰化酶活性呈两态分布,慢代谢者占16.7%,CYP1A2和XO酶活性呈对数正态分布,其代谢比值与国外文献报道一致。提示通过测定咖啡因代谢物比值,可以进行NAT2酶、CYP1A2酶和黄嘌呤氧化酶活性分析。     

Molecular phenotype of a human lymphoblastoid cell-line homoplasmic for the np 7445 deafness-associated mitochondrial mutation

We have studied mitochondrial gene expression and metabolic function in a human lymphoblastoid cell-line homoplasmic for the np 7445, deafness- associated mitochondrial DNA mutation. The mutation maps to the 3' termini of the oppositely oriented genes encoding cytochrome oxidase subunit I (COI) and tRNA-ser(UCN). In comparison with control lymphoblastoid cells, we detected a marked depletion (> 60%) of tRNA- ser(UCN). There was, however, no significant impairment of respiratory function, no alteration to the structure or abundance of COI mRNA or its precursors, and no detectable abnormality of mitochondrial protein synthesis. We also found considerable tissue-variation in the abundance of tRNA-ser(UCN). We propose that the tissue-specific phenotype associated with this mutation results from an inherent deficiency in the processing of the mutant pre-tRNA, that becomes limiting for protein synthesis only in a restricted set of cells of the auditory system in which the tRNA is, for other reasons, already at a critically low level.      

Immunohistologic Analysis of Estrogen Receptor Expression in Breast Carcinoma Precursor Lesions

Abstract: The growth of invasive breast carcinoma is facilitated by abnormal expression of estrogen receptor (ER), however, the status of ER during disease histogenesis is poorly defined. The extent of ER immunostaining (expressed as percentage of positive cells) was semiquantitated in the invasive (ICA) and corresponding in situ (CIS) components of 50 formalin-fixed, paraffin-embedded breast carcinomas and then compared to staining in normal terminal duct lobular units (TDLU) or hyperplastic lesions (if present) in the same tissue sections. Morphologically normal TDLUs from most cases (61%) exhibited ER staining in 11–30% of epithelial cells; only 10% of the cases had TDLUs demonstrating immunoreactivity in more than 50% of cells. In contrast, 80% of the hyperplastic lesions showed ER staining in more than 30% of epithelial cells, with 44% demonstrating immuoreactivity in more than 50% of epithelial cell nuclei (p = 0.01, chi-square test). Although most in situ carcinomas showed even more extensive ER staining than hyperplasias (>70% of cells were positive in 50% of cases), a significant subset (28%) of CIS exhibited staining in less than 10% of cells (p = 0.002, chi-square test). Invasive carcinomas were less often extensively immunoreactive (i.e., >50% of cells positive) than CIS (32% versus 58% for CIS) and there were five cases (10%) in which the CIS component was ER positive but the invasive component was ER negative. Finally, ER-positive carcinomas were significantly more often accompained by extensive CIS and/or proliferative breast disease (p = 0.007 and 0.003, respectively). The divergent levels of ER expression observed between premalignant, preinvasive, and invasive lesions suggests that inappropriate regulation of hormone receptors may be a factor that promotes early growth or progression in breast neoplasia, and ER-positive breast carcinomas are characterized by a different, possibly lengthier, histogenesis than ER-negative malignancies with a greater frequency of background hyperplastic lesions and a larger preinvasive component.