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排序方式: 共有452条查询结果,搜索用时 15 毫秒
1.
AIM:To investigate expression and function of CD40 ligand by peripheral blood mononuclear cells (PBMCs) in patients with systemic lupus erythematosus (SLE).METHODS:Expression of CD40 ligand by PBMCs in patients with SLE and control were examined by flow cytometric analysis before and after stimulated by phytohemagglutinin(PHA)and depressed by Dexamethasone(Dex). The correlation between expression of CD40 ligand and SLE activity index(SLEDAI) was analysed in patients with SLE.RESULTS:The expression of CD40 ligand by PBMCs in patients with active SLE was higher than that in patients with inactive SLE and control. Though the expression of CD40 ligang by PBMCs could be stimulated by PHA in three groups, it was the highest in patients with active SLE. Dex depressed the expression of CD40 ligand by PBMCs significantly in patients with SLE, but not in control. There was high positive correlation between expression of CD40 ligand and SLEDAI in patients with active and inactive SLE.CONCLUSION:Increased expression of CD40L by PBMCs in patients with SLE may play an important role in pathogenesis of SLE. 相似文献
2.
为研究文心兰热激蛋白70基因(命名为OnHSP70)的分子特性及表达特点,以文心兰‘柠檬绿’(Oncidium hybridum ‘Honey Angel’)为材料,采用RT-PCR技术克隆OnHSP70,利用生物信息学方法分析其分子特性,通过qRT-PCR技术分析其在不同组织及不同非生物胁迫处理下的表达特点。生物信息学分析表明:该基因开放阅读框为1944 bp,编码647个氨基酸,翻译的蛋白为稳定蛋白,属于HSP70超家族,其蛋白二级结构由41.11%的α-螺旋、17.77%的延伸链、7.73%的β-转角和33.38%的无规卷曲组成,具有2个高度保守的功能域。聚类分析表明:该蛋白与铁皮石斛和深圳拟兰的HSP70亲缘关系较近。qRT-PCR分析表明:文心兰HSP70在4种不同组织器官中具有表达差异性,在花中的表达量最高;高温处理后基因的表达量明显上升;40 ℃高温胁迫4 h时表达量达峰值;茉莉酸甲酯及水杨酸处理时表达量呈现下调响应。本研究为后期该基因功能研究及提高文心兰对高温的适应性提供理论基础。 相似文献
3.
为了表达牛环形泰勒虫(Theileria annulata)截短HSP70基因编码蛋白并研究该蛋白的结构与功能特性,本研究扩增牛环形泰勒虫HSP70目的基因并构建重组质粒pMD18-T-HSP70,选取其他种的同源HSP70蛋白序列构建系统进化树;利用生物信息学方法分析HSP70基因编码蛋白的氨基酸组成、基本理化性质、亲疏水性、跨膜区结构、信号肽、可能的磷酸化位点、亚细胞定位及蛋白的二级结构和三级结构;对重组蛋白HSP70进行蛋白互作网络分析;构建原核表达载体pET28a-HSP70,筛选诱导表达条件,镍柱纯化重组蛋白及检测反应原性。结果显示,牛环形泰勒虫HSP70蛋白序列与小泰勒虫的序列同源性较高,蛋白分子质量为42 ku,理论等电点(pI)为5.61,属于酸性亲水性蛋白,无跨膜区及信号肽;蛋白功能预测结果显示,HSP70包含32个可能的磷酸化位点,亚细胞定位分析显示该蛋白主要分布于细胞质。蛋白质二级结构中α-螺旋、β-转角、无规则卷曲、延伸链分别占39.18%、8.51%、30.41%和21.91%。蛋白互作网络构建结果显示,与HSP70相互作用的蛋白主要为HSP90家族成员,另外还有伴侣蛋白GrpE同系物,预示着HSP70可能在细胞内与HSP90形成复合体发挥作用。本试验成功构建原核表达载体,获得了大小约为48 ku的融合蛋白,以0.6 mmol/L IPTG于37 ℃诱导5 h,蛋白表达较好;点状印迹及Western blotting结果表明,表达产物可被自然感染的牛环形泰勒虫阳性血清识别,具有良好的反应原性。本试验结果为进一步探讨牛环形泰勒虫HSP70功能机制提供了理论依据。 相似文献
4.
5.
盐胁迫下栽培大豆黑农40不同器官中抗氧化酶活性的变化 总被引:1,自引:0,他引:1
通过对盐胁迫下栽培大豆黑农40的根、茎、叶等不同器官中主要的抗氧化酶活性的测定与分析,探讨了大豆耐盐性的机理.结果表明,黑农40叶片中的SOD、POD和APX活性水平明显高于根部和茎部.叶片中的POD和APX在高盐胁迫下的应答反应都比在低盐时快速.盐胁迫时间的延长引起根、茎、叶中的SOD和POD活性发生明显的下降,在高盐胁迫下这种下降比在低盐时更为急剧. 相似文献
6.
The effects of starving and feeding on Dover sole (Solea solea,Soleidae, Linnaeus, 1758) stress response and early larval development 下载免费PDF全文
Chiara Carla Piccinetti Marco Donati Giuseppe Radaelli Giovanni Caporale Gilberto Mosconi Francesco Palermo Lina Cossignani Roberto Salvatori Rocio Penuela Lopez Ike Olivotto 《Aquaculture Research》2015,46(10):2512-2526
In the view of an urgent necessity to improve the quantity and the quality of farmed fish species, there is a strong need to improve our basic knowledge on the effects of first feeding during the developmental stages of fish larvae. High mortality, mainly due to food deprivation or inappropriate food quality, has been observed in many larval fish species, but knowledge about the morphological, biochemical and molecular processes related to this topic is still poorly understood. The understanding of the early larval ontogeny as well as the larval nutritional requirements and the molecular and cellular mechanisms elicited by fish larvae during food deprivation and starvation are thus of primary importance. At this regard, this study investigates, in Dover sole larvae, the effects of starvation and starving/re‐feeding procedures at a morphological, histological, biochemical and molecular level. The results evidenced that starved larvae progressively decrease in growth, lipid content, affected their gastrointestinal tract and muscle development and increased cortisol and heat shock protein 70 levels. On the contrary, starved and re‐fed larvae showed, after the restoration of a favourable feeding condition, a compensatory growth. In conclusion, this is the first study analysing through a multidisciplinary approach the effects of food deprivation on the development of an important economic species, the Dover sole. 相似文献
7.
Hongli Xia Huimin Fan Meng Long Jun Cheng Wenjie Chen Dapeng Yu Liqun Xia Yishan Lu 《Journal of fish diseases》2021,44(1):45-52
Streptococcus agalactiae is a Gram‐positive facultative intracellular bacterium that leads to severe economic loss of tilapia worldwide. Previous studies demonstrated that CD40 contributes to host protection against intracellular injection. In this study, CD40 was characterized from Nile tilapia (Oreochromis niloticus), named OnCD40. Sequence analysis showed that open reading frame of OnCD40 was 933 bp, containing a single peptide, a transmembrane domain and four cysteine‐rich domains. The qRT‐PCR revealed that OnCD40 was expressed in all examined tissues with the most abundant ones in spleen and thymus. After S. agalactiae stimulation, the expression of OnCD40 was significantly induced in most of the detected organs. Moreover, OnCD40‐overexpressing fish elicited significant protection against subsequent S. agalactiae challenge; approximately 10000‐fold fewer bacteria were detected in spleen of OnCD40‐overexpressing fish in comparison with control fish. Thus, CD40 had protecting function in Nile tilapia against intracellular pathogens. 相似文献
8.
Expression of HSP70 in response to heat-shock and its cDNA cloning from Mediterranean blue mussel 总被引:1,自引:0,他引:1
Haruhiko?ToyoharaEmail author Masatomi?Hosoi Isao?Hayashi Satoshi?Kubota Hisashi?Hashimoto Yoshihiro?Yokoyama 《Fisheries Science》2005,71(2):327-332
Expression of HSP70 in response to heat-shock was investigated at the protein and mRNA levels in Mediterranean blue mussel.
Western and Northern blot analyses revealed that HSP70 was expressed following heat-shock in the mantle at both protein and
mRNA levels, suggesting that gene expression of HSP70 is implicated in the cellular response to heat-shock stress in mussel.
It was then attempted to clone HSP70 cDNA in order to determine the primary structure of mussel HSP70. As a result, two full-length
cDNA encoding HSP70 were isolated from a cDNA library prepared from the heat-shocked mantle. The isolated cDNA consist of
single open reading frames of 2067 bp and 1911 bp which encode proteins of 689 amino acids and 637 amino acids, respectively.
Both HSP70 cDNA encode an ATPase do main, and a substrate-binding do main in addition to a Glu-Glu-Val-Asp (EEVD) peptide
motif that is specific for cytosolic HSP70. These findings suggest that the cDNA clones obtained in the present study encode
cytosolic HSP70. 相似文献
9.
Heat shock protein 70 expression in different tissues of Cirrhinus mrigala (Ham.) following heat stress 总被引:2,自引:0,他引:2
Members of heat shock protein 70 (HSP70) are highly conserved proteins of about 70 kDa and play important roles in protein folding. Levels of these proteins increase when cells are under stress. Environmental temperature influences both the basal and induced levels of HSPs. However, studies on HSPs in fishes from a tropical country such as India are lacking. In the present study, Indian major carp (IMC) Cirrhinus mrigala (Ham.) acclimatized at 25±2°C had high levels of HSP70, viz., 1.2–1.3 ng μg?1 total protein in kidney and gill and 4.2–5.3 ng μg?1 total protein in liver and brain tissues, indicating the presence of biochemically significant levels of stress. However, maintenance of acclimatized fish at 17°C for up to 48 h did not lead to a significant decrease in stress protein levels. A heat shock at 37°C for up to 48 h resulted in only two to threefold increase in HSP70 levels in these organs. Although the increase in HSP70 levels was apparent from the first hour of heat stress in all these tissues, the increase was significant from the second hour in the brain, the sixth hour in liver and kidney and the 20th hour in the gills. 相似文献
10.
Differential HSP90α expression in fish hepatocytes from polluted estuary during summer 总被引:2,自引:0,他引:2
The molecular chaperone, heat shock protein 90α (HSP90α), plays an important role in protein folding, degradation of denatured
proteins and steroid activation. It is essential for the maintenance of cellular integrity and survival when induced in response
to environmental, physical and chemical stresses. In the present investigation the effect of environmental stress on HSP90α
expression was examined in grey mullet Mugil cephalus living in either a contaminated (Ennore) or uncontaminated (Kovalam) estuary over two seasons: Hepatocytes were isolated
from grey mullet of both estuaries. Oxidative stress was determined along with HSP90α in these fish. Additionally, immunohistochemical
changes were studied to confirm the HSP90α expression. Comparison of the results revealed enhanced hepatocyte oxidative stress
and HSP90α expressions in fish from Ennore to a significant extent than fish from Kovalam. Also, the results showed significant
seasonal variations with maximum expression observed during summer compared to the monsoon season. Overexpression of HSP90α
in hepatocytes exposed to chronic environmental stress by pollutants may confer differential effects on cell survival by protecting
against oxidative stress induced changes. The results also indicate that seasonal variations have significant effect on the
HSP90α expression. 相似文献