Myelin ultrastructure of sciatic nerve in rat experimental autoimmune neuritis model and its correlation with associated protein expression

To explore the relationship of peripheral nerve ultrastructure and its associated protein expression in experimental autoimmune neuritis (EAN). EAN was established in Lewis rats using an emulsified mixture of P0 peptide 180-199, Mycobacterium tuberculosis, and incomplete Freund’s adjuvant. Rats immunized with saline solution were used as a control group. Sciatic nerve ultrastructure and immunofluorescence histopathology were measured at the neuromuscular severity peak on day 18 post-induction. Cell-specific protein markers were used for immunofluorescence histopathology staining to characterize sciatic nerve cells: CD3 (T cell), Iba-1 (microglia), S100 (myelin), and neurofilament 200 (axon). The results showed that swelling of the myelin lamellae, vesicular disorganization, separation of the myelin lamellae, and an attenuation or disappearance of the axon were observed by transmission electron microscopy in the EAN group. CD3 and Iba-1 increased significantly in the structures characterized by separation or swelling of the myelin lamellae, and increased slightly in the structures characterized by vesicular of the myelin lamellae, S100 decreased in the structures characterized by vesicular disorganization or separation of the myelin lamellae. And neurofilament 200 decreased in the structures characterized by separation of the myelin lamellae. Furthermore, we found that Iba1 were positive in the myelin sheath, and overlapped with S100, which significantly indicated that Schwann cells played as macrophage-like cells during the disease progression of ENA. Our findings may be a significant supplement for the knowledge of EAN model, and may offer a novel sight on the treatment of Guillain-Barré syndrome.     

Role of transcriptional factor Nrf2 in the acute lung injury of mice

Objective: This study aimed to investigate the expression and role of Nrf2 in the acute lung injury (ALI) of mice. Methods: A total of 60 BABL/c mice were randomly divided into 2 groups: ALI group and control group. In ALI group, ALI was introduced by injection of LPS. Immunohistochemistry was performed to detect Nrf2 expression in the lung; Western blot assay was employed to detect the expression of Nrf2 in the lung homogenate; ELISA was conducted to detect the expression of Nrf2 in the lung homogenate and BALF. Results: As compared to control group, ALI mice had a high Nrf2 expression in the lung as shown in immunohistochemistry, and the Nrf2 expression in the lung homogenate and BALF also increased markedly (P<0.05). Conclusion: The Nrf2 expression increases in the lung and BALF of ALI mice, suggesting that Nrf2 is involved in the inflammation during ALI and may serve as a new target in the therapy of ALI.     

口腔黏膜鳞状细胞癌、上皮异常增生及正常黏膜组织拉曼光谱研究

目的 研究口腔黏膜鳞状细胞癌、上皮重度异常增生及正常黏膜组织的拉曼光谱特征,以期为拉曼光谱诊断口腔黏膜癌变提供依据.方法 收集手术切除的新鲜口腔黏膜鳞状细胞癌组织56例,重度上皮异常增生组织50例及正常黏膜组织32例,采用配备光纤探头的便携式拉曼光谱仪获取拉曼光谱.应用主成分分析法(principle component analysis,PCA)结合判别函数分析(discriminant function analysis,DFA)对不同组织的光谱数据进行分析,建立诊断模型对口腔鳞状细胞癌、上皮重度异常增生及正常黏膜的光谱数据进行鉴别,应用交互验证方法对诊断模型进行验证.结果 口腔鳞状细胞癌、上皮重度异常增生及正常黏膜组织间的拉曼光谱存在差异,主要表现为口腔鳞状细胞癌和上皮重度异常增生组织光谱中对应核酸、蛋白质及脂类物质的谱峰明显高于正常黏膜上皮组织;鉴别诊断建模的总体分类准确率达96.4％(133/138),交互验证的分类准确率达92.8％(128/138).结论 口腔鳞状细胞癌和上皮重度异常增生组织中细胞增殖代谢明显高于正常黏膜组织;应用PCA-DFA建立的分类诊断模型可以很好地区分3种不同组织的光谱数据.     

ε-聚赖氨酸与灭菌注射用水湿化效果二阶段交叉试验分析

目的采用二阶段交叉试验分析ε-聚赖氨酸与灭菌注射用水的湿化效果。方法选择我院神经内科94例长期氧疗患者行分组研究。按患者入院顺序将其编号,再按随机数字表法将其分为A组(n=47)及B组(n=47)。A组第一阶段湿化液为灭菌注射用水,第二阶段湿化液为ε-聚赖氨酸;B组第一阶段湿化液为ε-聚赖氨酸,第二阶段湿化液为灭菌注射用水。对比两组采样菌落数、合格率及氧疗舒适度。结果通过二阶段交叉试验发现:A组及B组在应用ε-聚赖氨酸作为湿化液期间菌落数更少(P0.01)。湿化液灭菌注射用水的合格率为82.98%,明显低于ε-聚赖氨酸的合格率100.00%(P0.01)。与灭菌注射用水相比,应用ε-聚赖氨酸作为湿化液具有更温暖、更湿润、舒适度更高、异味及噪声更少等优点(P0.01)。结论应用ε-聚赖氨酸作为氧疗湿化液可有效减少湿化液污染,增进患者氧疗舒适度,值得临床推广应用。     

Diagnostic accuracy of loop-mediated isothermal amplification in detection of Clostridium difficile in stool samples: a meta-analysis

Introduction

Clostridium difficile infection (CDI) remains a diagnostic challenge for clinicians. More recently, loop-mediated isothermal amplification (LAMP) has become readily available for the diagnosis of CDI, and many studies have investigated the usefulness of LAMP for rapid and accurate diagnosis of CDI. However, the overall diagnostic accuracy of LAMP for CDI remains unclear. In this meta-analysis, our aim was to establish the overall diagnostic accuracy of LAMP in detection of Clostridium difficile (CD) in stool samples.

Material and methods

A search was done in PubMed, MEDLINE, EMBASE and Cochrane Library databases up to February 2014 to identify published studies that evaluated the diagnostic role of LAMP for CD. Methodological quality was assessed according to the quality assessment for studies of diagnostic accuracy (QUADAS) instrument. The sensitivities (SEN), specificities (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR) were pooled statistically using random effects models. Statistical analysis was performed by employing Meta-Disc 1.4 software. Summary receiver operating characteristic (SROC) curves were used to summarize overall test performance. Funnel plots were used to test the potential publication bias.

Result

A total of 9 studies met inclusion criteria for the present meta-analysis. The pooled SEN and SPE for diagnosing CD were 0.93 (95% CI: 0.91–0.95) and 0.98 (95% CI: 0.98–0.99), respectively. The PLR was 47.72 (95% CI: 15.10–150.82), NLR was 0.07 (95% CI: 0.04–0.14) and DOR was 745.19 (95% CI: 229.30−2421.72). The area under the ROC was 0.98. Meta-regression indicated that the total number of samples was a source of heterogeneity for LAMP in detection of CD. The funnel plots suggested no publication bias.

Conclusions

The LAMP meets the minimum desirable characteristics of a diagnostic test of SEN, SPE and other measures of accuracy in the diagnosis of CD, and it is suitable as a rapid, effective and reliable stand-alone diagnostic test for diagnosis of CDI, potentially decreasing morbidity and nosocomial spread of CD.     

Toll-like receptor 4 gene polymorphisms and susceptibility to colorectal cancer: a meta-analysis and review

Introduction

Many case-control studies have investigated the association between toll-like receptor 4 (TLR4) Asp299Gly and Thr399Ile polymorphisms and risk of colorectal cancer (CRC). However, published data are still conflicting.

Material and methods

A systematic search was conducted in the electronic databases of PubMed, MEDLINE, EMBASE, Web of Science and CNKI between 2000 and 2014. The associations between TLR4 polymorphisms and CRC susceptibility were assessed by pooled odds ratios (ORs) and 95% confidence intervals (95% CI) in fixed or random effects models.

Results

In total nine case-control studies were identified in this meta-analysis. For TLR4 Asp299Gly polymorphism, 9 studies included 1198 cases and 1290 controls. The GG genotype carriers had higher risk for developing CRC than AA + GA genotype carriers (OR = 1.95, 95% CI: 1.00–3.77, p = 0.05). No association was found in other genetic models (p > 0.05). Analysis stratified by ethnicity showed no association in any genetic models among the Asian or Caucasian population. For TLR4 Thr399Ile polymorphism, 6 studies contained 619 cases and 632 controls. The overall analysis showed significantly increased risk in TT homozygote carriers compared to CC homozygote (OR = 4.99, 95% CI: 1.41–17.65, p = 0.01) and C carriers (TC + CC) (OR = 4.50, 95% CI: 1.27–15.87, p = 0.02). In terms of analyses stratified by race, a significant association was found in each genetic model among the Asian population, rather than the Caucasian group.

Conclusions

The GG homozygote carriers of TLR4 Asp299Gly and TT homozygote carriers of TLR4 Thr399Ile polymorphisms might be correlated with an increased risk of CRC, suggesting they may serve as genetic risk factors for CRC.     

miR-34c-3p inhibits cell proliferation,migration and invasion of hepatocellular carcinoma by targeting MARCKS

Recent studies have shown that microRNA-34c-3p (miR-34c-3p) is down-regulated in various types of cancers and involved in tumor growth, invasion and metastasis. However, the roles of miR-34c-3p in hepatocellular carcinoma (HCC) are poorly understood. In this study, the expression profile of miR-34c-3pin HCC tissues and cell lines were examined by quantitative real-time polymerase chain reaction (qRT-PCR). The correlations of miR-34c-3p expression and clinicopathological characteristics were analyzed. The biological role of MiR-34c-3pin cell proliferation, migration and invasion was examined. In addition, the targets of miR-34c-3p were identified. The results showed that miR-34c-3p expression was significantly down-regulated in HCC tissues and cell lines; low expression level of miR-34c-3p was correlated with vascular invasion and advanced TNM stage. In vitro functional assays showed that overexpression of miR-34c-3pin HepG2 and Huh7 cells significantly reduced cell proliferation, migration and invasion. Furthermore, target analysis and luciferase assay identified myristoylated alanine-rich protein kinase c substrate (MARCKS) as a specific target of miR-34c-3p. Knockdown of MARCKS in HepG2 cells reduced cell migration and invasion, but not cell proliferation. Taken together, our findings implicate the potential application of miR-34c-3p as a tumor suppressor in cancer therapy.