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Growth and feeding habits of invasive Pseudorasbora parva in the Chabalang Wetland(Lhasa,China) and its trophic impacts on native fish

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Journal of Oceanology and Limnology 2019年第2期37卷 628-639页

作者： DING Huiping GU Xiaohong ZHANG Zhiming HUO Bin LI Dapeng XIE Congxin State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China University of Chinese Academy of Sciences Beijing 100049 China College of Fisheries Huazhong Agricultural University Wuhan 430070 China Institute of Hydroecology MWR & CAS Wuhan 430070 China Key Laboratory of Ecological Impacts of Hydraulic-Projects and Restoration of Aquatic Ecosystem Ministry of Water Resources Wuhan 430070 China

In recent years, fish invasion has become one of the main reasons for the decline of native fish stocks. Pseudorasbora parva is considered one of the major invasive species worldwide. The present study investigated the fish resources of the Chabalang Wetland (Lhasa, Tibet) during diff erent seasons in 2009 and 2013. Four hundred and twelve individuals were subsampled to estimate age, growth, and feeding habit of P . parva . Furthermore, food relationships between P . parva and the native Schizothoracinae fish were also examined. The results revealed a significant shift in species composition and community structure characterized by the disappearance of native fish and outbreak of non-native fish. The percentage of nonnative P . parva in the fish collections significantly increased from 33.64% in 2009 to 64.08% in 2013. The standard length (SL) ranged from 22.00 to 78.71 mm, and their age was 1–5 a. The von Bertalanff y function was used to model the observed length-at-age data as L t =112.19(1–e^-0.1495 ( t +0.8012)) for females and as L t =123.12 (1–e^-0.1500 ( t +0.7132)) for males. The results indicated that P . parva in Tibet has lower growth and mortality rates compared with that from the native ranges. Ninety-seven prey taxa belonging to 9 prey categories were identified in the gut of 38 P . parva . P . parva can be considered a generalized and opportunistic predator, competing with the native fish, especially Schizothorax o’connori , Schizopygopsis younghusbandi younghusbandi , and Ptychobarbus dipogon , for Bacillariophyta and Chironomid larvae. This is an important reason for the decline in native fish population.

关键词： Pseudorasbora parva growth feeding habits Schizothoracinae fish biological invasion

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Perforin Expression in <i>Theileria parva</i>Specific Cytotoxic T Cells Correlates with Cytotoxicity

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Open Journal of Immunology 2014年第3期4卷 117-127页

作者： Jerome Wendoh Rebecca Waihenya Rosemary Saya Elias Awino Vishvannath Nene Lucilla Steinaa International Livestock Research Institute Nairobi Kenya Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya Kenya Medical Research Institute Nairobi Kenya

Theileria parva is a protozoan parasite that causes the disease East Coast fever in cattle which results in major economic losses in Eastern, Central and Southern Africa. Efforts to generate vaccines involve measurements of cytotoxic activity since CD8 cells are believed to be responsible for protection of the animals. CTL assays are time consuming, and may require use of radioactive material and they also impose a considerable amount of in vitro work, which may skew the response compared to ex vivo assays. Hence it would be beneficial to identify other markers that correlate with the cytotoxicity. In this in vitro study we examined if the number of tetramer positive CD8 cells and the staining intensity of these correlated with lysis of the target cells. Furthermore, we investigated if the expression of the activation marker perforin correlated with the cytotoxicity. Perforin is involved in permeabilization of the cell membrane of the target cell. Bulk CTL lines and purified CD8 cell lines generated from cattle of the A18 BoLA (MHC) type were analysed for the Theileria parva specific immune responses using a peptide-MHC tetramer and antibodies for perforinin FACS analysis. Thelysis of target cells was determined by a chromium release assay. Results demonstrate that the percentage of tetramer positive cells, in six cell lines generated against the whole parasite, correlate with killing of PBMC pulsed with the peptide. The product of the percentages of perforin and tetramer double positive cells and the net MFI of perforin showed a perfect correlation with the cytotoxicity of the peptide pulsed PBMC. Likewise, the product of percentage perforin positive cells and the staining intensity had the best significant correlation with killing of the pulsed PBMC. The present results suggest that perforin could be a possible biomarker for the cytotoxicity to Theileria parva infections/immunizations.

关键词： Cytotoxic T Cells Biomarkers Perforin Theileria parva

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parva在鼻咽癌中的表达及其对鼻咽癌细胞生物学功能的影响

PARVA在鼻咽癌中的表达及其对鼻咽癌细胞生物学功能的影响

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作者：罗承长广西医科大学

学位级别：硕士

目的:鼻咽癌是一种起始于鼻咽粘膜的上皮恶性肿瘤,好发于我国南方地区,尤其是广西和广东两省。鼻咽癌发病部位隐匿,恶性程度高,容易发生转移,绝大多数病患就诊时已届于疾病的中晚期,预后情况很差。越来越多的研究表明癌基因的激活是鼻... 详细信息

目的:鼻咽癌是一种起始于鼻咽粘膜的上皮恶性肿瘤,好发于我国南方地区,尤其是广西和广东两省。鼻咽癌发病部位隐匿,恶性程度高,容易发生转移,绝大多数病患就诊时已届于疾病的中晚期,预后情况很差。越来越多的研究表明癌基因的激活是鼻咽癌发生发展的重要因素。近年来,研究发现parva基因在多种癌症中表达增高,且其表达增高与癌症的发生和转移相关。目前,尚未有parva在鼻咽癌中的报道。本文主要研究parva在鼻咽癌中的表达情况及其对鼻咽癌细胞生物学功能的影响。方法:1.利用实时荧光定量PCR(quantitative Reverse Transcription Polymerase Chain Reaction,q RT-PCR)和蛋白免疫印迹(Western blot,WB)检测人正常鼻咽上皮细胞NP69与鼻咽癌细胞HK1、HONE1和5-8F中parva m RNA和蛋白质层面的表达水平。2.应用慢病毒载体介导的RNA干扰(RNA interference,RNAi)技术,沉默HK1和5-8F细胞中的parva表达,并设置相应的阴性对照组。应用荧光倒置显微镜观察慢病毒感染效果和计算感染效率,分别通过q RT-PCR和WB法检测各组细胞parva m RNA和蛋白质的表达情况,以确认沉默效果。3.采用CCK-8实验检测沉默parva对HK1和5-8F细胞增殖能力的影响。4.应用细胞划痕和Transwell迁移实验检测parva表达抑制对HK1和5-8F细胞迁移能力的影响。5.通过WB技术检测parva对鼻咽癌上皮-间质转化(epithelialmesenchymal transition,EMT)进程的影响。结果:1.与NP69相比,HK1和5-8F中parva的表达量相对较高,因此选择这两株鼻咽癌细胞进行后续的细胞功能实验。2.实验组和阴性空载组的慢病毒转染效率均大于80%;与阴性空载组相比,parva m RNA和蛋白质在实验组的表达量均显著降低(pparva的鼻咽癌细胞株。***-8实验结果表明,沉默parva表达后,5-8F和HK1细胞的增殖能力显著降低(pparva后5-8F及HK1细胞中的EMT相关蛋白的表达量发生改变,包括Ecadherin蛋白表达升高,N-cadherin及Vimentin蛋白表达降低。结论:1.与正常鼻咽上皮细胞相比,parva的表达水平在鼻咽癌细胞中明显增高。***可显著促进鼻咽癌细胞的增殖和迁移能力。***可能通过EMT机制促进鼻咽癌的进展。

关键词：鼻咽癌 parva 增殖迁移

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