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双单倍体 1

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Observations on pathological and histochemical changes in piglet livers infected with Taenia saginata asiatica

LINGHU Yan, ZHU Wujun, BAO Huai′en, CHEN Yan

《医学前沿（英文）》 2007年第1卷第3期页码 258-263 doi: 10.1007/s11684-007-0049-8

摘要： To study the pathological and histochemical characteristics of lesions in piglet livers infected with () throughout the different stages, piglets were fed with eggs of and raised in isolation in an animal center to establish the infection model with normal piglets as control. The pathological changes in the piglet livers were observed after the infection using liver sections stained with hematoxylin and eosin. Histochemical methods were used to check the changes in lipid, glycogen and protein content in the liver. The data collected by image analysis were analyzed statistically with Statistical Package for the Social Science. The results show that -exposed piglets were indeed infected. Inflammatory reactions began on the fourth day and progressed rapidly. Kupffer cell hyperplasia, hepatic hydropic degeneration and ballooning degeneration were found in the 10th 20th days after infection. Hepatic central veins and hepatic sinusoids were dilated and congested. Spotty necrosis occurred in some local liver tissues. In the 40th–60th days, granulomatous reactions and mild hepatocirrhosis were the main lesions. In the 70th–80th days, hepatocirrhosis and bile duct proliferation were observed in the liver. In the different stages, lipid drops were increased while glycogen and protein levels were decreased to some degree. There was a significant difference in metabolism between the infected group and the control group (〈0.01). It is concluded that pigs are the favorable intermediate host of and its infection can result in serious pathological and histochemical lesions in host organs.

关键词： hydropic degeneration significant difference -exposed favorable intermediate different

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Adenovirus-mediated tissue inhibitor of metalloproteinase-3 gene transfection inhibits rabbit intervertebral disc degeneration

Xudong YU MM, Zengwu SHAO MD, Liming XIONG MD, Weiwei XU MM, Hezhong WANG MM, Huifa XU MM,

《医学前沿（英文）》 2009年第3卷第4期页码 415-420 doi: 10.1007/s11684-009-0072-z

摘要： The aim of this study was to investigate the inhibitory effects of recombinant adenovirus vector carrying tissue inhibitor of metalloproteinase-3 (RAdTIMP-3) against degeneration of rabbit intervertebral disc. Thirty Japanese white rabbits of 4 months old were randomly divided into 5 groups. Mild or moderate rabbit lumbar disc degeneration model was constructed with the controllable axial loading device by imposing 98N pressure at the discs for 2 weeks. Various doses of virus were injected into the degenerated discs as follows: 20μL of normal saline in group 1; 20μL of RAd66 (an empty adenovirus vector, 1.0×10OPU/mL) in group 2; and 20, 10, and 5μL of RAdTIMP-3 (1.0×10OPU/mL) in groups 3, 4, and 5, respectively. Two weeks after the injection, the discs were collected for investigations, including assessment of degeneration degrees according to the Thompson’s grading system, reverse-transcription polymerase chain reaction (RT-PCR) assay for TIMP-3 gene, Safranin O-Fast green staining, and immunohistochemical staining for TIMP-3 and type II collagen. According to Thompson’s criteria, the degeneration of groups 3, 4, and 5, especially group 3, was alleviated as compared with groups 1 and 2. RT-PCR revealed that the expression of TIMP-3 in groups 3, 4, and 5, especially in group 3, was significantly enhanced as compared with group 1 (<0.01). Both Safranin O-Fast green staining and type II collagen staining demonstrated better reserved integrity of disc matrix in groups 3, 4, and 5 than in groups 1 and 2. TIMP-3 staining exhibited an obvious increase of positive-staining rate in groups 3, 4, and 5 as compared with group 1. The positive-staining rate in group 3 (79.42%±1.35%) was about 3times that of group 1 (25.47%±5.46%, <0.01). RAdTIMP-3 can effectively protect the matrix of rabbit intervertebral disc against overloading-induced degeneration in a dose-dependent manner, resulting in the alleviation of disc degeneration.

关键词： tissue inhibitor of metalloproteinase-3 intervertebral disc rabbit gene therapy

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Strain and process engineering toward continuous industrial fermentation

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1336-1353 doi: 10.1007/s11705-022-2284-6

摘要： Most current biotechnology industries are based on batch or fed-batch fermentation processes, which often show low productivity and high production costs compared to chemical processes. To increase the economic competitiveness of biological processes, continuous fermentation technologies are being developed that offer significant advantages in comparison with batch/fed-batch fermentation processes, including: (1) removal of potential substrates and product inhibition, (2) prolonging the microbial exponential growth phase and enhancing productivity, and (3) avoiding repeated fermentation preparation and lowering operation and installation costs. However, several key challenges should be addressed for the industrial application of continuous fermentation processes, including (1) contamination of the fermentation system, (2) degeneration of strains, and (3) relatively low product titer. In this study, we reviewed and discussed metabolic engineering and synthetic biology strategies to address these issues.

关键词： continuous fermentation productivity contamination strain degeneration metabolic engineering

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双单倍体牙鲆的性腺发生、性别分化及早期发育的研究

王桂兴,朱以美,侯吉伦,张晓彦,王玉芬,孙朝徽,姜秀凤,刘海金

《中国工程科学》 2014年第16卷第9期页码 33-41

摘要：

本文利用组织切片的方法研究了双单倍体牙鲆的性腺发生、性别分化及早期发育。结果显示：双单倍体牙鲆中除雌性外，还有雄性和未分化鱼出现，所占比例分别为56 %、38 %和6 %。双单倍体牙鲆雌性的性别分化晚于普通牙鲆。雌鱼至100 日龄，卵巢腔仍未闭合；110 日龄雌鱼的产卵板上存在大量向卵母过渡的卵原细胞，未见Ⅰ时相卵母细胞出现。双单倍体牙鲆雄鱼精巢的分化在时间上和普通牙鲆的基本相同。随着发育的进行，双单倍体牙鲆雌鱼的卵巢出现部分异常的卵母细胞以及卵巢退化现象；部分雄鱼的精巢也有退化现象出现。9~11 月龄，双单倍体牙鲆雄鱼的精巢发育到Ⅲ期，而普通牙鲆性腺在同期进入了Ⅳ期；11 月龄开始双单倍体牙鲆雄鱼精巢有退化的迹象；13~15 月龄，精巢退化成精小叶，其中只含有精原细胞，初级精母细胞消失不见，似Ⅱ期精巢。

关键词：牙鲆双单倍体性腺退化