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.     

Nicotinate-Curcumin Impedes Foam Cell Formation from THP-1 Cells through Restoring Autophagy Flux

Our previous studies have indicated that a novel curcumin derivate nicotinate-curcumin (NC) has beneficial effects on the prevention of atherosclerosis, but the precise mechanisms are not fully understood. Given that autophagy regulates lipid metabolism, the present study was designed to investigate whether NC decreases foam cell formation through restoring autophagy flux in oxidized low-density lipoprotein (ox-LDL)-treated THP-1 cells. Our results showed that ox-LDL (100 μg/ml) was accumulated in THP-1 cells and impaired autophagy flux. Ox-LDL-induced impairment of autophagy was enhanced by treatment with the autophagy inhibitor chloroquine (CQ) and rescued by the autophagy inducer rapamycin. The aggregation of ox-LDL was increased by CQ, but decreased by rapamycin. In addition, colocalization of lipid droplets with LC3-II was remarkably reduced in ox-LDL group. In contrast, NC (10 μM) rescued the impaired autophagy flux by significantly increasing level of LC3-II, the number of autophagolysosomes, and the degradation of p62 in ox-LDL-treated THP-1 cells. Inhibition of the PI3K-Akt-mTOR signaling was required for NC-rescued autophagy flux. Notably, our results showed that NC remarkably promoted the colocalization of lipid droplets with autophagolysosomes, increased efflux of cholesterol, and reduced ox-LDL accumulation in THP-1 cells. However, treatment with 3-methyladenine (3-MA) or CQ reduced the protective effects of NC on lipid accumulation. Collectively, the findings suggest that NC decreases lipid accumulation in THP-1 cells through restoring autophagy flux, and further implicate that NC may be a potential therapeutic reagent to reverse atherosclerosis.     

长萼兰花蕉(Orchidantha chinensis var.longisepala)的繁育系统研究

通过野外观察并采用杂交指数（OCI）测定、花粉/胚珠比（P/O）检测、人工控制授粉等方法,对长萼兰花蕉（Orchidantha chinensis var.longisepala（D.Fang） T.L.Wu）种群的繁育系统进行了研究,采用常规石蜡切片与扫描电子显微镜（SEM）观察了柱头与"V"形黏盘的结构与形态。结果表明,长萼兰花蕉单花花期一般为18 d,依其花部形态的变化可分为蕾期、花萼未反转期、花萼反转期、唇瓣枯萎期、花萼枯萎期5个时期;根据杂交指数值为4、P/O值为253.89 ±21.09、人工异花授粉结实率分别为45%（2014年）和75%（2015年）,显示出长萼兰花蕉的繁育系统属于异交,且需要传粉者。石蜡切片观察到长萼兰花蕉黏盘区与柱头可授区之间是光滑的表皮细胞,结合人工授粉实验与分泌物含糖量测定结果表明,长萼兰花蕉的"V"形黏盘不具有可授性,其作用可能是分泌黏液附着在传粉者背部使其便于携带花粉。长萼兰花蕉整个花期环境湿冷、多雨且开花同步性较低,这些因素很可能造成其有效传粉媒介缺乏,影响了传粉成功;另一方面,长萼兰花蕉有性繁殖受到限制,其主要通过根状茎进行无性繁殖后代,所以分布范围比较狭窄。