Neuropsychological function in adolescents sustaining mild closed head injury

Adolescents sustaining mild closed head injury were evaluated for mental functioning immediately following injury. Evaluation of their neuropsychological performance in comparison with healthy adolescents and adolescents sustaining severe closed head injury revealed a pattern distinct from the other two groups. Mildly injured patients exhibited some dysfunction in verbally based measures of learning, abstraction, and reasoning, while appearing unimpaired on measures of attention, motor speed, and visual memory.     

Antienterobacterial activity of Hemidesmus indicus R. Br. root extract

The antienterobacterial activity of the chloroform and methanol extracts of Hemidesmus indicus root was demonstrated using a variety of methods and different enterobacterial strains. Although the constituents were similar in the chloroform extract (CHI) and the fatty substance separated (ME1) from the methanol extract (MHI), ME1 was found to be more effective than CHI as evident from the disc diffusion method. ME1 was found to be more active than MHI, followed by CHI. This may be due to the inefficient diffusion of CHI into the medium. In a modified agar well diffusion and swab method the activity of the extract against different strains was observed in a single plate. The extracts inhibited growth in a dose dependent manner; both MHI and CHI were most effective against S. flexneri, least effective against S. dysenterie and moderately effective against the other strains. The presence of antimicrobial trace elements such as copper and zinc, along with other active constituents may contribute to the antienterobacterial activity of Hemidesmus indicus root.     

CHI3L1在神经系统相关疾病的新进展

几丁质酶–3类蛋白–1（chitinase3–like protein1,CHI3L1）是近年来新发现的炎性标记物之一,是一种甲壳素结合凝集素,归属于糖基水解酶家族18。大量研究表明,CHI3L1在多种炎症性疾病及肿瘤的发病机制中起着重要作用,包括哮喘、脓毒症、糖尿病、肝硬化、慢性阻塞性肺疾病、冠状动脉疾病、神经系统疾病等。本文将重点阐述CHI3L1在神经系统相关疾病方面的研究进展。     

Stair-related injuries treated in United States emergency departments

Objective

To investigate the characteristics of stair-related injuries among individuals of all ages and estimate national injury frequencies and rates using a representative sample of patients treated in United States emergency departments.

基于Oncomine数据库及GEPIA数据库分析CHI3L2基因在胶质母细胞瘤中的表达及与预后的相关性

目的:基于Oncomine数据库及GEPIA数据库分析CHI3L2基因在胶质母细胞瘤中的表达及与预后的相关性。方法:检索Oncomine和GEPIA数据库中相关胶质母细胞瘤的数据集,分析胶质母细胞瘤组织与正常对照组织之间基因表达的差异,采用GEPIA数据库进行在线生存分析。结果:Oncomine数据库中共收集了449项关于CHI3L2基因在肿瘤与正常组织中表达比较的研究结果,表达差异有统计学意义的研究结果有23项,其中有9项研究结果呈高表达,14项研究结果呈低表达。与对照组相比,在胶质母细胞瘤组织中CHI3L2的表达显著高于正常组织（P＜0.05）。结论:CHI3L2在胶质母细胞瘤组织中呈高表达,且与胶质母细胞瘤患者预后相关,为临床胶质母细胞瘤的治疗及基因靶向药物的研制提供重要理论依据。     

Chitinase 3-like 1 is a profibrogenic factor overexpressed in the aging liver and in patients with liver cirrhosis

Older age at the time of infection with hepatitis viruses is associated with an increased risk of liver fibrosis progression. We hypothesized that the pace of fibrosis progression may reflect changes in gene expression within the aging liver. We compared gene expression in liver specimens from 54 adult donors without evidence of fibrosis, including 36 over 40 y old and 18 between 18 and 40 y old. Chitinase 3-like 1 (CHI3L1), which encodes chitinase-like protein YKL-40/CHI3L1, was identified as the gene with the greatest age-dependent increase in expression in liver tissue. We investigated the cellular source of CHI3L1 in the liver and its function using liver tissue specimens and in vitro models. CHI3L1 expression was significantly higher in livers of patients with cirrhosis of diverse etiologies compared with controls represented by patients who underwent liver resection for hemangioma. The highest intrahepatic CHI3L1 expression was observed in cirrhosis due to hepatitis D virus, followed by hepatitis C virus, hepatitis B virus, and alcohol-induced cirrhosis. In situ hybridization of CHI3L1 messenger RNA (mRNA) identified hepatocytes as the major producers of CHI3L1 in normal liver and in cirrhotic tissue, wherein hepatocytes adjacent to fibrous septa showed higher CHI3L1 expression than did those in more distal areas. In vitro studies showed that recombinant CHI3L1 promotes proliferation and activation of primary human hepatic stellate cells (HSCs), the major drivers of liver fibrosis. These findings collectively demonstrate that CHI3L1 promotes liver fibrogenesis through a direct effect on HSCs and support a role for CHI3L1 in the increased susceptibility of aging livers to fibrosis progression.

It is well-established that the incidence of severe liver disease with rapid liver fibrosis progression in humans is increased in the elderly, although the underlying mechanisms remain to be elucidated (1). The role of age has been particularly well documented in patients with hepatitis C virus (HCV) infection, where age at the onset of infection was found to be a major determinant for fibrosis progression and disease severity in immunocompetent subjects (2–6). Likewise, donor age was shown to have a major impact on graft outcome after liver transplantation for end-stage HCV disease: When the donors were younger than 40, the interval to cirrhosis was 10 y, whereas when the donors were 41 to 50 or older, the intervals were 6.7 and 2.7 y, respectively (7). Collectively, these data suggest that age-related changes in liver response to injury play a key role in determining the increased susceptibility of the aging liver to fibrosis (2, 4, 7).We hypothesized that the different rate of liver fibrosis progression in patients over 40 y of age could reflect changes in gene expression in aging livers. To test this hypothesis, we studied a large series of liver specimens from 54 well-characterized liver transplant donors by comparing gene expression between liver donors less than and over 40 y of age. We identified chitinase 3-like 1 (CHI3L1) as the gene with the greatest age-dependent increase in expression. CHI3L1, also known as YKL-40 in humans, is a secreted glycoprotein of ∼40 kDa (8), which has been shown to play a critical role in a variety of human diseases associated with inflammation, tissue remodeling, and injury (9–12). A correlation between serum levels of CHI3L1 with aging was previously documented in a large cohort of healthy individuals in Denmark (13). Elevated levels of CHI3L1 in serum have also been reported as a biomarker of liver fibrosis in patients with chronic liver disease of any etiology (9, 12, 14–18). However, the mechanisms underlying the correlation between increased circulating CHI3L1 levels and liver fibrosis have not yet been determined. There is very limited information on the expression of CHI3L1 in primary liver tissue, since in most previous studies serum was the sole clinical material analyzed. Thus, in this study, we investigated the source of CHI3L1 and the mechanisms linking CHI3L1 with liver fibrosis by using primary liver tissue and in vitro models.     

Role of breast regression protein-39/YKL-40 in asthma and allergic responses

BRP-39 and its human homolog YKL-40 have been regarded as a prototype of chitinase-like proteins (CLP) in mammals. Exaggerated levels of YKL-40 protein and/or mRNA have been noted in a number of diseases characterized by inflammation, tissue remodeling, and aberrant cell growth. Asthma is an inflammatory disease characterized by airway hyperresponsiveness and airway remodeling. Recently, the novel regulatory role of BRP-39/YKL-40 in the pathogenesis of asthma has been demonstrated both in human studies and allergic animal models. The levels of YKL-40 are increased in the circulation and lungs from asthmatics where they correlate with disease severity, and CHI3L1 polymorphisms correlate with serum YKL-40 levels, asthma and abnormal lung function. Animal studies using BRP-39 null mutant mice demonstrated that BRP-39 was required for optimal allergen sensitization and Th2 inflammation. These studies suggest the potential use of BRP-39 as a biomarker as well as a therapeutic target for asthma and other allergic diseases. Here, we present an overview of chitin/chitinase biology and summarize recent findings on the role of BRP-39 in the pathogenesis of asthma and allergic responses.     

钛表面接枝溴代十六烷后的杀菌效果研究

目的 在钛表面沉积透明质酸(HA)和壳聚糖(CHI)聚电解质多层膜,并用溴代十六烷对CHI上的氨基季铵化,以评价其杀菌效果.方法 在碱化处理过的钛片上吸附带正电荷的聚乙烯亚氨(PEI),再用层层自组装的方法在钛表面交替沉积带负电荷的HA和带正电荷的CHI,并用溴代十六烷(C16H33Br)对CHI上的氨基季铵化,形成Ti-PEI-(HA-CHI)20-N+(C16H33)3Br涂层,扫描电子显微镜(SEM)对涂层断面进行表征;以纯钛为对照组,Ti-PEI-(HA-CHI)20和Ti-PEI-(HA-CHI)20-N+(C16H33)3Br-为实验组,分别在其表面进行变形链球菌(S.m)培养24h后用荧光显微镜和SEM检测钛片表面的细菌活性.结果 SEM显示聚电解质多层膜已沉积到钛片表面并具有一定的厚度.荧光显微镜显示纯钛表面有大量的活细菌,Ti-PEI-(HA-CHI)20上细菌数量较少,且有部分死菌;而Ti-PEI-(HA-CHI)20-N+(C16H33)3Br-上细菌几乎全为死菌.SEM结果显示纯钛、Ti-PEI-(HA-CHI)20、Ti-PEI-(HA-CHI)20-N+(C16H33)3Bf 3组钛片上的细菌数量依次减少.结论 钛表面沉积HA/CHI聚电解质多层膜,并对多层膜中的CHI季铵化后,其表面具有显著的杀菌作用.