2011年、2013年和2016年医院内获得性血流感染常见病原菌分布及其耐药性分析

动态监测2011年、2013年和2016年我国不同地区医院内获得性血流感染病原菌分布及耐药进展趋势。从全国10个城市回顾性收集血流感染病原菌非重复性株,采用琼脂稀释法或微量肉汤稀释法进行药物敏感性试验,采用Whonet 5.6软件对药敏试验结果进行分析。收集的2 248株血流感染病原菌中革兰阴性杆菌为1 657株 (占73.7%),革兰阳性球菌为591株 (占26.3%)。分离率排名前五的病原菌依次为大肠埃希菌 (32.6%,733株/2 248株)、肺炎克雷伯菌 (14.5%,327株/2 248株)、金黄色葡萄球菌 (10.0%,225株/2 248株)、鲍曼不动杆菌 (8.7%,196株/ 2 248株) 和铜绿假单胞菌 (6.2%,140株/2 248株)。血流感染分离的革兰阴性杆菌对抗菌药物体外敏感率较高的抗菌药物依次为粘菌素 (96.5%,1 525株/1 581株,不包括天然耐药菌株)、替加环素 (95.6%,1 375株/1 438株,不包括天然耐药菌株)、头孢他啶/克拉维酸 (89.2%,1 112株/1 246株)、阿米卡星 (86.4%,1 382株/1 599株) 和美罗培南 (85.7%,1 376株/1 605株);革兰阳性球菌对抗菌药物体外敏感率较高的抗菌药物依次为替加环素、替考拉宁和达托霉素 (敏感率均为100.0%)、万古霉素和利奈唑胺 (敏感率均为99.7%)。2011年、2013年和2016年产超广谱β-内酰胺酶肠杆菌科细菌分离率分别为50.6% (206株/407株)、49.8% (136株/273株) 和38.9% (167株/429株);碳青霉烯不敏感肠杆菌科细菌分离率分别为2.2% (9株/408株)、4.0% (16株/402株) 和3.9% (17株/ 439株);多重耐药鲍曼不动杆菌分离率分别为76.4% (55株/72株)、82.7% (43株/52株) 和87.5% (63株/72株),多重耐药铜绿假单胞菌分离率分别为9.8% (5株/51株)、20.0% (7株/35株) 和13.0% (7株/54株);甲氧西林耐药金黄色葡萄球菌的分离率分别为51.9% (41株/79株)、29.7% (19株/64株) 和31.7% (26株/82株)。屎肠球菌和粪肠球菌中高水平庆大霉素耐药株分离率分别为43.2% (48株/111株) 和40.9% (27株/66株)。碳青霉烯不敏感肠杆菌科细菌中肺炎克雷伯菌居首位,占57.1% (24株/42株) 。肠杆菌科细菌中分离出30株替加环素不敏感株,其中肺炎克雷伯菌占76.7% (23株/30株);分离出粘菌素耐药肠杆菌科细菌39株,其中大肠埃希菌、阴沟肠杆菌和肺炎克雷伯菌分别占43.6% (17株/39株)、35.9% (14株/39株) 和15.4% (6株/39株)。医院获得性血流感染病原菌主要为革兰阴性杆菌 (以大肠埃希菌和肺炎克雷伯菌为主),其对替加环素、粘菌素和碳青霉烯类药物的敏感率较高;革兰阳性球菌中分离率最高的为金黄色葡萄球菌,其次为屎肠球菌,这两种细菌对替加环素、达托霉素、利奈唑胺、万古霉素和替考拉宁的敏感率较高。粘菌素耐药肠杆菌科细菌、替加环素不敏感肠杆菌科细菌、利奈唑胺或万古霉素不敏感革兰阳性球菌的分离,警示临床高度关注,仍需动态监测耐药进展趋势。     

浙江西门岛海洋特别保护区大型底栖动物功能群特征及其与环境的关系

为研究浙江西门岛海洋特别保护区大型底栖动物功能群的变化规律及其与环境因子的关系,作者分别于2010年4月(春季)、11月(秋季),2011年8月(夏季)和2012年2月(冬季)进行了4个航次的大型底栖动物调查,共鉴定出大型底栖动物78种,根据其食性类型划分为浮游生物食者、植食者、肉食者、杂食者、碎屑食者5种功能群.各功能群平均密度从高到低依次为浮游生物食者＞肉食者＞植食者＞碎屑食者＞杂食者,平均生物量从高到低依次为浮游生物食者＞碎屑食者＞肉食者＞杂食者＞植食者.单因素方差分析结果表明,大型底栖动物各功能群的密度和生物量季节间均无显著性差异.典范对应分析结果表明,影响大型底栖动物功能群的主要环境因子包括温度、溶解氧、溶解态无机磷和表层沉积物的中值粒径,排序轴对功能群-环境关系的贡献率计算结果表明环境变量可以较好地解释功能群的变化情况.     

Plasticity in R/S ratio, morphology and fitness-related traits in response to reciprocal patchiness of light and nutrients in the stoloniferous herb, Glechoma longituba L

Clonal fragments of the stoloniferous herb Glechoma longituba were subjected to a complementary patchiness of light and soil nutrients including two spatially homogeneous treatments (SR–SR and IP–IP) and two spatially heterogeneous treatments (IP–SR and SR–IP). SR and IP indicate patches (shaded, rich) with low light intensity (shaded, S), high nutrient availability (rich, R) and patches (illuminated, poor) with high light intensity (illuminated, I) and low nutrient availability (poor, P), respectively. Plasticity of the species in root–shoot ratio, fitness-related traits (biomass, number of ramets and dry weight per ramet) and clonal morphological traits (length and specific length of stolon internodes, area and specific area of laminae, length and specific length of petioles) were experimentally examined. The aim is to understand adaptation of G. longituba to the environment with reciprocal patches of light and soil nutrients by plasticities both in root–shoot ratio and in (clonal) morphology. Our experiment revealed performance of the clonal fragments growing from patches with high light intensity and low soil nutrient availability into the adjacent opposite patches was increased in terms of the fitness-related characters. R/S ratio and clonal morphology were plastic. Meanwhile, the capture of light resource from the light-rich patches was enhanced while the capture of soil nutrients from either the nutrient-rich or the nutrient-poor patches was not. Analysis of cost and benefit disclosed positive effects of clonal integration on biomass production of ramets in the patches with low light intensity and high soil nutrient availability. These results suggest an existence of reciprocal translocation of assimilates and nutrients between the interconnected ramets. The reinforced performance of the clonal fragments seems to be related with specialization of clonal morphology in the species.     

Tenascin-R distinct domains modulate migration of neural stem/progenitor cells in vitro

Extracellular matrix (ECM) molecules constitute a "niche" that modulates the migration, proliferation, and differentiation of neural stem/progenitor cells (NSPCs). The glycoprotein Tenascin-R (TN-R) is an ECM molecule, comprising multiple domains. Either the whole TN-R molecule or its distinct domains has been demonstrated to play a very important role in the developing central nervous system. However, little is known about the effect of the TN-R domain on NSPCs, especially NSPC migration. In the present study, we first show that both TN-R domains epidermal growth factor-like repeat (EGFL) and fibronectin type III (FN)6-8 can inhibit the NSPCs migration from neurospheres in vitro. Furthermore, both the EGFL and FN6-8 domains affect the distribution of neurons generated from neurospheres, indicating that EGFL and FN6-8 domains inhibit the motility of neurons generated from neurospheres. These results suggest that TN-R has an inhibitory effect on NSPCs migration.     

Targeting to overexpressed glucose-regulated protein 78 in gastric cancer discovered by 2D DIGE improves the diagnostic and therapeutic efficacy of micelles-mediated system

The survivals of gastric cancer (GC) patients are associated with early diagnosis and effective treatments. Therefore, it is urgent for the discovery of early GC biomarkers and tumor-targeting therapeutics. The aim of this study was to uncover putative tissue biomarkers of GC using 2D DIGE and then apply one of these specific markers in GC treatment. We found three putative biomarkers of GC with significant differences in expression level compared to adjacent normal tissue, including glucose-regulated protein 78 (GRP78) and glutathione s-transferase pi (GSTpi) with increased expression level, and alpha-1 antitrypsin (A1AT) with reduced expression level. The overexpressed GRP78 was used as a targeted protein for guiding the drugs to tumor cells, leading to more effective treatment for GC xenografts. Our results demonstrated that the designated GRP78-binding peptide based on the sequence, WIFPWIQL, was selectively prone to recognize and bind to GC MKN45 cells in vitro, and also improve the delivery efficiency of polymeric micelles-encapsulated drugs into tumor cells and displayed better therapeutic outcome in experimental animals. This strategy of GRP78-mediated drug targeting system may bring chemotherapeutic drugs with more precise targeting to tumor cells, leading to minimize side effects on patients after chemotherapy.