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941.
ZHAO QianQian FENG YanLing JIA XiaoFang YIN Lin ZHENG Ye OUYANG DongSheng ZHOU HongHao ZHANG LiJun 《中国科学:生命科学英文版》2014,57(3):303-314
Elucidation of the mechanisms of liver fibrogenesis is important to treat liver fibrosis.In this study,we established rat models of liver fibrosis with stages from 0–1,2,and 3–4 to 4 at 2,4,6,and 8 weeks,respectively,by injection of pig serum.Liver fibrogenesis was detected by Masson’s trichrome staining.Rat non-parenchymal cells(NPCs)were enriched 4-fold by Percoll density gradient centrifugation.Protein extracts from NPCs were prepared at 4 and 8 weeks,separated by two-dimensional electrophoresis,and then stained with Coomassie Blue G-250.At 4 weeks,we identified 18 non-redundant differentially expressed proteins of which protein disulfide-isomerase associated protein 3(PDIA3)and NDUV showed consistent expression at protein and mRNA levels from 4 to 8 weeks.PDIA3 was found to be down-regulated by Western blotting in the rat model and immunohistochemically in human liver.Our results revealed important aspects of the pathogenesis/progression of liver fibrosis and demonstrated important changes in protein expression levels of NPCs at various stages of liver fibrosis. 相似文献
942.
Xuexia Liang Dingbo Shi Jingping Yun Yanping Mao Puyun Ouyang Zhen Su Jia Fu Jinghui Hou Wuguo Deng Fangyun Xie 《Translational oncology》2014,7(4):493-502
This study aimed to investigate the expression pattern and prognostic value of friend leukemia virus integration 1 (FLI-1) in nasopharyngeal carcinoma (NPC). Immunohistochemistry (IHC) staining of FLI-1 was performed in specimens from 198 untreated NPC patients. Ninety-nine patients were randomly assigned to the training set to analyze the prognostic value of FLI-1 and other clinicopathological characteristics, while the others were assigned to the testing set for validation. Clinicopathological data were compared using the Pearson chi-square test. Univariate and multivariate analyses were performed using the Cox proportional hazards model to test independent prognostic factors and calculate the hazard ratio (HR) and 95% confidence interval (CI). Cytoplasmic FLI-1 expression positively correlated with N stage, distant metastasis and death (P< 0.05) and also predicted poorer overall survival (OS) (P= 0.014), distant metastasis-free survival (DMFS) (P= 0.010), progression-free survival (PFS) (P= 0.031). In multivariate analysis, FLI-1 expression and clinical stage were both independent prognostic factors of poor OS and DMFS. Prognoses of patients in the training set, the testing set, and the entire set were clearly divided into four risk subgroups by supplementing FLI-1 with clinical stage. These results indicate that FLI-1 expression is an independent prognostic factor for NPC patients and suggest that supplementing FLI-1 with clinical stage could be helpful for more accurate risk definition. 相似文献
943.
Meiyan Zhong Yuanting Huang Bo Zeng Lihui Xu Chunsu Zhong Jiahao Qiu Xunjia Ye Mingye Chen Bo Hu Dongyun Ouyang Xianhui He 《Acta biochimica et biophysica Sinica》2022,(1):64-76
Macrophages are critical sentinel cells armed with multiple regulated necrosis pathways,including pyroptosis,apoptosis followed by secondary necrosis,and necrop... 相似文献
944.
Dan Zhang Zongqi Xu Hong Xu Xiaohai Feng Sha Li Heng Cai Yan Wei Pingkai Ouyang 《Biotechnology and Bioprocess Engineering》2011,16(6):1144-1151
In this study, the production of poly(γ-glutamic acid) by Bacillus subtilis NX-2 (PGA) at different agitation speeds was investigated. Based on the analysis of specific cell growth rate (μ) and specific
PGA formation rate (q
p
), a two-stage strategy for agitation speed control was proposed. During the first 24 h, an agitation speed of 600 rpm was
used to maintain a high μ for better cell growth, which then reduced to 400 rpm after 24 h to maintain a high q
p
to enhance PGA production. Using this method, the maximum concentration of PGA reached 40.5 ± 0.91 g/L and the PGA productivity
was 0.56 ± 0.012 g/L/h, which was 17.7 and 9.8% higher, respectively, than the best results obtained when a constant agitation
speed was used. The flux distributions and the related enzymes of 2-oxoglutarate could be affected by this two-stage strategy
for agitation speed. The activity of isocitrate dehydrogenase and glutamate dehydrogenase at the key node of 2-oxoglutarate
increased, and more flux distribution was directed to glutamate. The flux distribution from extracellular to intracellular
glutamate also increased and improved PGA production as the glutamate uptake rates increased using the agitation-shift control
method. 相似文献
945.
Microarray analysis of gene expression profiles of rat small intestine in response to heat stress 总被引:1,自引:0,他引:1
Lu A Wang H Hou X Li H Cheng G Wang N Zhu X Yu J Luan W Liu F Xu J 《Journal of biomolecular screening》2011,16(6):655-667
Ambient temperature is a critical factor that affects biological organisms in many ways. In this study, the authors investigated gene expression changes in rat small intestine in response to heat stress. Male Sprague-Dawley rats were randomly divided into control and heat-stressed groups. Both groups were housed at 25 °C, although the heat-stressed group was also subjected to 40 °C for 2 h each day for 10 successive days. Rats were sacrificed 1, 3, 6, and 10 days after heat treatment, and sections of their small intestine epithelial tissue were excised for morphological examination and microarray analyses. The rat rectal and body surface temperatures and serum cortisol levels were all significantly increased after heat treatment (p < 0.05). The jejuna were significantly damaged by 3 days after heat treatment began. Microarray analysis showed that 422 genes were differentially expressed, of which 290 genes were significantly upregulated and 132 genes were significantly downregulated. Subsequent bioinformatics analyses revealed that the differentially expressed genes were mainly related to stress, immune regulation, and metabolism processes. The bioinformatics analysis of the differentially expressed genes should be beneficial to further investigations on the underlying mechanisms involved in heat stress-induced damage in the small intestine. 相似文献
946.
Conversion of mouse fibroblasts into cardiomyocytes using a direct reprogramming strategy 总被引:1,自引:0,他引:1
Here we show that conventional reprogramming towards pluripotency through overexpression of Oct4, Sox2, Klf4 and c-Myc can be shortcut and directed towards cardiogenesis in a fast and efficient manner. With as little as 4 days of transgenic expression of these factors, mouse embryonic fibroblasts (MEFs) can be directly reprogrammed to spontaneously contracting patches of differentiated cardiomyocytes over a period of 11-12 days. Several lines of evidence suggest that a pluripotent intermediate is not involved. Our method represents a unique strategy that allows a transient, plastic developmental state established early in reprogramming to effectively function as a cellular transdifferentiation platform, the use of which could extend beyond cardiogenesis. Our study has potentially wide-ranging implications for induced pluripotent stem cell (iPSC)-factor-based reprogramming and broadens the existing paradigm. 相似文献
947.
948.
pH and reduction dual-sensitive copolymeric micelles for intracellular doxorubicin delivery 总被引:1,自引:0,他引:1
This study develops novel pH and reduction dual-sensitive micelles for the anticancer drug doxorubicin (DOX) delivery owing to the fact that the tumor tissues show low pH and high reduction environment. These sub-100 nm micelles present a core-shell structure under physiological conditions, but quickly release the loaded drugs responding to acidic and reductive stimuli. With disulfide bonds in each repeat unit of poly(β-amino ester)s, the novel copolymer was synthesized via Michael addition polymerization from 2,2'-dithiodiethanol diacrylate, 4,4'-trimethylene dipiperidine, and methoxy-PEG-NH(2). DOX released faster from micelles in a weakly acidic environment (pH 6.5) than at pH 7.4 or in the presence of a higher concentration (5 mM) of reducing agent (DTT). The release is even more effective in a scenario of both stimuli (pH 6.5 and 5 mM DTT). MTT assay showed that the DOX-loaded micelles had a higher cytotoxicity for HepG2 tumor cells than DOX at higher concentrations, and that blank micelles had a very low cytotoxicity to the tumor cells. Confocal microscopy observation showed that the micelles can be quickly internalized, effectively deliver the drugs into nuclei, and inhibit cell growth. These results present the copolymer as a novel and effective pH and reduction dual-responsive nanocarrier to enhance drug efficacy for cancer cells. 相似文献
949.
Ca(2+) transfer from endoplasmic reticulum (ER) to mitochondria at contact sites between the organelles can induce mitochondrial dysfunction and programmed cell death after stress. The ER-localized chaperone glucose-regulated protein 78kDa (GRP78/BiP) protects neurons against excitotoxicity and apoptosis. Here we show that overexpressing GRP78 protects astrocytes against ischemic injury, reduces net flux of Ca(2+) from ER to mitochondria, increases Ca(2+) uptake capacity in isolated mitochondria, reduces free radical production, and preserves respiratory activity and mitochondrial membrane potential after stress. We conclude that GRP78 influences ER-mitochondrial Ca(2+) crosstalk to maintain mitochondrial function and protect astrocytes from ischemic injury. 相似文献
950.
Li X Zhang J Gao Y Yang Y Xu C Li G Guo G Liu S Xie J Liang S 《Purinergic signalling》2011,7(4):489-497
Pain is a major problem after burns. Procedural pain evoked by burn dressing changes is common in patients, and its management
is a critical part of treatment in acute burn injuries. Burn pain is very likely the most difficult form of acute pain to
treat. ATP contributes to inflammation, and ATP is implicated in peripheral pain signaling via actions upon P2X3 receptors. Puerarin is extracted from a traditional Chinese medicine and may act on P2X3 receptor mechanisms. The Visual Analogue Scale (VAS) has been shown to be a sensitive indicator of pain intensity and treatment
effects. Peripheral blood mononuclear cells (PBMCs) are involved in nociception or pain after burn injury. Burn patients were
randomly divided into normal saline (NS) group (salt solution is saline) and puerarin-treated group and pain (Visual Analogue
Scale scores) and inflammation (PBMCs) measured. Burn pain produces a stress response, so blood glucose, insulin, and cortisol
levels in burn patients were determined. Furthermore, the expression of P2X3 protein and mRNA in PBMCs was detected. The VAS scores in the puerarin-treated group were lower than those in NS group. The
blood glucose, insulin, and cortisol levels in the puerarin-treated group at post-dressing changes were significantly decreased
in comparison with those in NS group. The expression levels of P2X3 protein and mRNA in PBMCs of burn patients in NS group were significantly increased in comparison with those in the puerarin-treated
group. Puerarin can antagonize inflammatory factors (such as ATP) and decrease the upregulated expressions of P2X3 protein and mRNA in PBMCs after burns to decrease VAS. Thus, puerarin had an analgesic effect on procedural pain in dressing
changes of burn patients related to P2X3 receptors. 相似文献