混交林和纯竹林与毛竹害螨爆发成灾关系研究

报道在福建省6个不同生态区域内检查10对纯竹林与混交林受南京裂爪螨(Schizotetranychus nanjingensis)、竹缺爪螨(Aponychus corpuzae)、竹刺瘿螨(Aculus bambusae)对毛竹危害情况．结果表明,纯竹林受螨害重,危害指数达22．1％～44．7％,平均35％．混交林受害轻,危害指数为2．7％～28．6％,平均17．5％,混交林与纯竹林之间受害程度经t-测验表明均达到极显著差异．6个样地中纯竹林害螨总量高于其相对的混交林。分别达67．74％、152．47％、299．5％、857．75％、331．67％、26．55％。平均为289．28％;调查混交林天敌竹盲走螨(Typhlodromus bambusae)总量分别比相对纯竹林高95．45％、-18．13％、207．69％、837．5％、190．3％,平均262．5％．纯竹林中益、害螨比例分别达1：27、1：21、1：233、1：282、1：27,平均1：118,而其相对的混交林益、害螨比例为1：12、1：12、1：30、1：3、1：3、1：20,平均1：13．由此可见,纯竹林受螨害程度、害螨总量平均是混交林的2倍,而天敌数量少于相对混交林的2～3倍,益、害螨比例显著低于混交林(t=2．975,P=0．003)．本项研究揭示了由于受人为干扰(集约化管理、劈草、垦复)破坏了毛竹林原有的益螨-害螨-寄主植物之间相对稳定的平衡。导致毛竹害螨种群突发性增长,证明了纯竹林是诱发毛竹害螨爆发成灾成因的重要因素之一。     

甘肃省民勤沙区土壤结皮理化性质研究

以甘肃民勤沙区为研究区域 ,分别采集了不同地貌部位和不同植被类型下的土壤结皮 ,并对其理化性质进行了初步分析。从结皮土壤的机械组成、土壤盐分、土壤养分、土壤阳离子交换量等方面来看 ,丘间地状况都明显要优于灌丛沙包。这可能与丘间地地形低洼 ,有利于土壤物质汇聚 ,以及其接受的大气降尘远较灌丛沙包为多有关。对于灌丛沙包来讲 ,白刺沙包在理化性质上 ,其状况要优于红柳结皮和梭梭结皮 ,这主要与其对环境的适应性及其所处的演替阶段有关。从目前的植被演替情况来看 ,白刺是当地的顶极种群 ,最适应环境 ,因此结皮发育状况也好 ;红柳目前已经处于极度退化进程中 ,而梭梭为人工植被 ,人工植被因在演替阶段中不起决定作用 ,故理化性质较差。另外从该研究工作还可以看出 ,对白刺植被采取围封措施之后 ,可以显著地促进结皮的生长发育 ,提高结皮中的有机质、全 N、全 P、速效 N等养分以及 Ca CO3含量。     

鄱阳湖水生维管束植物生物量及其合理开发利用的初步建议

用4种不同的计算方法测定了鄱阳湖水生维管束植物的生物量。根据22个断面,199个采集点,398个样方的测定结果,得出鄱阳湖水生维管束植物的年生产量为431.76万吨(湿重),即相当于5.44×10~(-15)焦耳(能量)。其中,马来眼子菜、苦草和黑藻等3种合计约占总生物量的71.46%。全湖可供草食性鱼类食用的水生维管束植物约占总量的86.9%。文中还对4个植物带和9个群丛生物量的分布规律进行了讨论。提出了人工增殖草食性鱼类,调整湖中植被组成,保护和种植水生经济植物等合理开发利用鄱阳湖水生植物资源的初步建议。     

Intratumoral heterogeneity determines discordant results of diagnostic tests for human epidermal growth factor receptor (HER) 2 in gastric cancer specimens

Accurate assessment of human epidermal growth factor receptor (HER) 2 is essential for efficient selection of patients who may benefit from therapies targeting this surface receptor (e.g., trastuzumab). Intratumoral heterogeneity of HER2 expression may potentially contribute to inaccurate assessment of HER2 status. To clarify intratumoral heterogeneity of HER2 expression and its potential clinical impact on assessment of HER2 status, we analyzed 148 endoscopic biopsy specimens and 117 excisional tumor specimens collected from 148 patients with primary gastric cancer. Specifically, we assessed HER2 protein overexpression and gene amplification using, respectively, immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). There were 28 IHC-positive cases and 25 FISH-positive cases among these 148 patients. Heterogeneous HER2 protein expression was demonstrated in 23 of 29 (79.3%) IHC-positive cases, while gene expression heterogeneity was found in 11 of 25 (44.0%) FISH-positive cases. Intratumoral heterogeneity was the main reason of discordant results between IHC and FISH or between endoscopic biopsy and excisional tumor specimens. The clinical significance and impact of intratumoral HER2 expression heterogeneity on treatment outcome in gastric cancer require further studies.     

糖蜜酒精废液厌氧生物降解性能的BMP分析

在中温条件下,对pH值和营养比例两个影响因素进行了糖蜜酒精废液的BMP分析,探讨酒精废液在厌氧消化过程中产甲烷量、COD浓度的变化情况,以及COD去除率与产气量、pH值之间的关系。研究结果表明,厌氧处理法能够使糖蜜酒精废液的有机负荷大大降低,CODcr去除率最高可达90．6％;在调节营养比例的条件下,pH=8．5时甲烷菌活性最佳,其中COD．P=300：1的产甲烷量最高。     

New mechanism of nerve injury in Alzheimer’s disease: β‐amyloid‐induced neuronal pyroptosis

The present study was designed to investigate the role of β‐amyloid (Aβ_1‐42) in inducing neuronal pyroptosis and its mechanism. Mice cortical neurons (MCNs) were used in this study, LPS + Nigericin was used to induce pyroptosis in MCNs (positive control group), and Aβ_1‐42 was used to interfere with MCNs. In addition, propidium iodide (PI) staining was used to examine cell permeability, lactate dehydrogenase (LDH) release assay was employed to detect cytotoxicity, immunofluorescence (IF) staining was used to investigate the expression level of the key protein GSDMD, Western blot was performed to detect the expression levels of key proteins, and enzyme‐linked immunosorbent assay (ELISA) was utilized to determine the expression levels of inflammatory factors in culture medium, including IL‐1β, IL‐18 and TNF‐α. Small interfering RNA (siRNA) was used to silence the mRNA expression of caspase‐1 and GSDMD, and Aβ_1‐42 was used to induce pyroptosis, followed by investigation of the role of caspase‐1‐mediated GSDMD cleavage in pyroptosis. In addition, necrosulfonamide (NSA), an inhibitor of GSDMD oligomerization, was used for pre‐treatment, and Aβ_1‐42 was subsequently used to observe the pyroptosis in MCNs. Finally, AAV9‐siRNA‐caspase‐1 was injected into the tail vein of APP/PS1 double transgenic mice (Alzheimer's disease mice) for caspase‐1 mRNA inhibition, followed by observation of behavioural changes in mice and measurement of the expression of inflammatory factors and pyroptosis‐related protein. As results, Aβ_1‐42 could induce pyroptosis in MCNs, increase cell permeability and enhance LDH release, which were similar to the LPS + Nigericin‐induced pyroptosis. Meanwhile, the expression levels of cellular GSDMD and p30‐GSDMD were up‐regulated, the levels of NLRP3 inflammasome and GSDMD‐cleaved protein caspase‐1 were up‐regulated, and the levels of inflammatory factors in the medium were also up‐regulated. siRNA intervention in caspase‐1 or GSDMD inhibited Aβ_1‐42‐induced pyroptosis, and NSA pre‐treatment also caused the similar inhibitory effects. The behavioural ability of Alzheimer's disease (AD) mice was relieved after the injection of AAV9‐siRNA‐caspase‐1, and the expression of pyroptosis‐related protein in the cortex and hippocampus was down‐regulated. In conclusion, Aβ_1‐42 could induce pyroptosis by GSDMD protein, and NLRP3‐caspase‐1 signalling was an important signal to mediate GSDMD cleavage, which plays an important role in Aβ_1‐42‐induced pyroptosis in neurons. Therefore, GSDMD is expected to be a novel therapeutic target for AD.     

Synthesis of cluster mannosides via a Ugi four-component reaction and their inhibition against the binding of yeast mannan to concanavalin A

The Ugi four-component reaction (U-4CR) was utilized to prepare divalent and trivalent cluster mannosides with different scaffolds. The glycoclusters obtained were tested for their relative inhibitory potency against the binding of yeast mannan to concanavalin A by solid-phase enzyme-linked lectin assays (ELLA) using methyl alpha-D-mannopyranoside as a standard. Among them, a divalent mannoside containing aromatic groups showed the strongest binding affinity to concanavalin A.     

突触囊泡蛋白在ALS转基因鼠海马的表达变化

目的为了为揭示肌萎缩脊髓侧索硬化症（amyotrophic lateral sclerosis,ALS）认知功能障碍的机制提供依据,观察不同年龄ALS转基因小鼠海马中突触囊泡蛋白（synaptophysin,Syp）的表达情况。方法取95d、108d和122dALS转基因鼠海马,应用免疫荧光、Westernblot、RT-PCR技术检测Syp在海马中的表达变化。结果与同窝野生型鼠比较,Syp蛋白和mRNA表达水平在95d龄ALS转基因鼠海马中无明显变化,在108d与122d龄ALS转基因鼠海马中明显降低。结论Syp在ALS转基因鼠海马中表达减少表明,突触可塑性降低是ALS学习记忆能力下降的重要病理学基础。     

基于可变模糊评价模型的东山湾生态系统健康评价

根据东山湾海域环境污染现状和生态系统的特点,从水质环境、沉积物环境、生物残毒以及海洋生物方面构建了东山湾生态系统健康评价指标体系,提出了基于可变模糊评价模型的海湾生态系统健康评价方法,并利用该方法对东山湾生态系统健康状况进行了评价。结果表明:东山湾春季生态系统健康指数为2.36,秋季为2.44,均处于"良与中之间,偏良"水平,春季略优于秋季。影响东山湾生态系统健康状况的主要负面指标因子为鱼卵及仔鱼密度(春秋季健康指数均值为4.95)、营养水平(秋季健康指数为4.47)和底栖生物生物量(春季健康指数为3.59)。实例研究表明该方法通过准则参数α和距离参数p的不同组合变化,以线性与非线性相结合,能够较客观系统、标准量化地评价海湾生态系统健康状况的优劣,。     

反义寡核苷酸体外抗流感病毒活性

为了获得具有抗流感病毒活性的反义寡核苷酸,针对A型流感病毒基因组3′和5′端保守序列,设计并合成了多条硫代寡核苷酸(ODN)：3′端反义ODN(IV3#)与3′端正义ODN(IV3S);5′端反义ODN(IV4#)与5′端正义ODN(IV4S)以及由5′和3′端正义/反义保守序列组成的复合序列ODN(IV6#和IV7#)。测定了PSODN的体外细胞毒性和在MDCK细胞中对流感病毒复制的影响。结果表明：(1)PSODN浓度高达50μmol/L时对MDCK细胞末表现有毒性作用;(2)与流感病毒基因组5′端互补的ODN IV4#以及由5′和3′端保守序列构成的IV6#ODN和IV7#ODN均具有较高的抗病毒活性;如IV4#ODN浓度为1μmol/L时对流感病毒A/京防/861(H1N1)抑制率近50%,浓度为10μmol/L或更高时抑制率超过70%,且IV4#抑制病毒活性呈现明显的序列和剂量依赖性;(3)IV4#ODN不仅对A型流感病毒H1N1亚型有抑制作用,对H3N2亚型也表现较高的抑制活性;(4)病毒感染复数(MOI)对IV4#ODN抗病毒活性有一定影响,当MOI较低时,IV4#ODN表现的剂量效应关系更加明显。抗流感病毒反义寡核苷核IV4#ODN的发现为进一步研究流感新型药物奠定了实验基础。〖HTH〗关键词〖HTSS〗：流感病毒, 反义寡核苷酸, 体外细胞毒性, 抗病毒活性, 感染复数