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961.
目的建立四氯化碳诱导的兔肝纤维化动物模型,观察体外分离标记的自体骨髓单核细胞(ABM-MNCs)经肠系膜上静脉自体移植至肝纤维化区及周边区后的存活、定植状况。方法将40只普通级日本大耳家兔随机分为细胞移植组和对照组各20只,实验组腹腔注射40%CCl4橄榄油溶液建立肝纤维化模型,对照组腹腔注射等量生理盐水。细胞移植组于模型稳定后自体髂骨处抽取骨髓,采用氯化氨红细胞溶解法分离得到单核细胞,以5溴-2脱氧尿嘧啶核苷(BrdU)标记体外ABM-MNCs及鉴定;分离培养ABM-MNCs,将3×10^9个ABM-MNCs经肠系膜上静脉回输体内,对照组回输等量生理盐水,移植前、移植后3、7、14、21 d分别取肝组织固定,进行免疫组织化学检测。结果BrdU体外标记ABM-MNCs的免疫组织化学表现示:20μmol/L BrdU孵育ABM-MNCs 72 h的阳性标记率达95%;肝组织20μmol/L BrdU免疫组化染色切片显示:自体骨髓单核细胞移植后第3天,肝小叶中央静脉周围BrdU染色阳性,随着时间的推移,阳性染色逐渐增强,并逐步向肝组织内部延伸。阳性染色主要分布于肝组织汇管区周围组织,而对照组BrdU染色则阴性。结论ABM-MNCs经肠系膜上静脉移植后,可在纤维化区及周边区存活,定植。  相似文献   
962.
目的初步探讨螺旋藻对实验性急性肝损伤的保护作用机制。方法实验大鼠随机分为4组:空白组(KB),生理盐水组(NS),甘利欣组(GLX)和螺旋藻组(LXZ)。分组口服灌胃5 d,用四氯化碳(CC l4)建立急性大鼠肝损伤模型后继续灌胃2 d后取材,检测肝功、抗氧化指标、肠道菌群定量、内毒素、肿瘤坏死因子和病理。结果螺旋藻具有保肝作用。与甘利欣组比较,能明显保护肠道微生态平衡(P〈0.05),内毒素和肿瘤坏死因子升高程度不如甘利欣组明显(P〈0.05),SOD(超氧化物歧化酶)和px-GSH(还原型谷胱甘肽转移酶)水平明显偏高(P〈0.05)。结论提示螺旋藻不仅通过抗氧化起到抗肝损伤作用,而且还可通过调节肠道菌群紊乱—内毒素—肿瘤坏死因子α途径起到护肝效果。  相似文献   
963.
Nitric oxide (NO) serves as a messenger for cellular signaling and physiological reactions such as inflammatory responses in vivo. Fluorescent bioimaging of nitric oxide is a very useful tool in NO functional research. Although many encouraging results have been achieved in the field of NO fluorescent detection, there is rarely satisfying result in inflammatory NO imaging in vivo. Here we report that fluorescent 5′-chloro-2-(2′-hydroxyphenyl)-1H-naphtho[2,3-d]imidazol can coordinate with Cu(II) to form a non-fluorescent coordination compound, which is able to directly and quickly image NO in cellular system or in vivo inflammation system with a turn-on fluorescence, based on a redox action of Cu(II). It was used to image NO produced by inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS) activated murine macrophages. More importantly, it could image the NO production in an acute severe hepatic injury (ASHI) model of BALB/c mice induced by integrative LPS and d-galactosamine (GalN) treatment. The results prove that the 5′-chloro-2-(2′-hydroxyphenyl)-1H-naphtho[2,3-d]imidazol coordinated with cupric ions can serve as an excellent NO bioimaging agent in different biological systems especially in inflammation related systems, and it may be valuable for diagnostic and pathological studies of NO related diseases.  相似文献   
964.
FEZ1 (Fasciculation and elongation protein zeta 1) is an ortholog of the Caenorhabditis elegans protein UNC-76, involved in neuronal development and axon outgrowth, in that worm. Mammalian FEZ1 has already been reported to cooperate with PKC-zeta in the differentiation and polarization of PC12 neuronal cells. Furthermore, FEZ1 is associated with kinesin 1 and JIP1 to form a cargo-complex responsible for microtubule based transport of mitochondria along axons. FEZ1 can also be classified as a hub protein, since it was reported to interact with over 40 different proteins in yeast two-hybrid screens, including at least nine nuclear proteins. Here, we transiently over-expressed GFP-FEZ1full in human HEK293 and HeLa cells in order to study the sub-cellular localization of GFP-FEZ1. We observed that over 40% of transiently transfected cells at 3 days post-transfection develop multi-lobulated nuclei, which are also called flower-like nuclei. We further demonstrated that GFP-FEZ1 localizes either to the cytoplasm or the nuclear fraction, and that the appearance of the flower-like nuclei depends on intact microtubule function. Finally, we show that FEZ1 co-localizes with both, α- and especially with γ-tubulin, which localizes as a centrosome like structure at the center of the multiple lobules. In summary, our data suggest that FEZ1 has an important centrosomal function and supply new mechanistic insights to the formation of flower-like nuclei, which are a phenotypical hallmark of human leukemia cells.  相似文献   
965.
Role of ChREBP in hepatic steatosis and insulin resistance   总被引:1,自引:0,他引:1  
  相似文献   
966.
Schistosoma mansoni (S. mansoni) eggs trapped in the host liver elicit a chain of oxidative processes that may be, at least in part, responsible for the pathology and progression of fibrosis associated with schistosomal hepatitis. This study was designed to assess the protective effect of the antioxidant coenzyme-Q10 (Co-Q10) against experimental S. mansoni-induced oxidative stress in the liver, and its potential role as an adjuvant to praziquantel (PZQ) therapy. The oxidative stress and overall liver function were improved under Co-Q10 therapy as evidenced by significant reduction in oxidative stress markers and preservation of antioxidant factors. Liver fibrosis was also reduced with a positive impact on liver function. Moreover, addition of Co-Q10 to PZQ therapy caused: significant reduction of liver egg load, significant improvement of the redox status, and lastly decreased liver fibrosis.  相似文献   
967.
目的探讨中药乙肝散逆转免疫性肝纤维化过程中肝组织TIMP-1(金属蛋白酶组织抑制因子-1) 及MMP-2(间质金属蛋白酶-2)表达的变化.方法雄性Wistar大鼠尾静脉注射白蛋白建立免疫损伤性肝纤维化模型后,分组加用不同浓度的乙肝散颗粒饲料喂养12周,流式细胞仪定量分析大鼠肝组织TIMP-1和MMP-2基因表达量,观察大鼠肝组织病理、苦味酸-天狼红染色、Ⅳ胶原免疫组化、α-SMA(α平滑肌肌动蛋白)免疫组化、肝匀浆Hyp(羟脯氨酸).结果乙肝散应用组肝组织TIMP-1表达量较模型对照组明显降低(P<0.01),MMP-2变化无统计学差异;同时肝组织Ⅰ胶原、Ⅲ胶原、Ⅳ胶原水平和Hyp含量明显降低(P<0.01或P<0.05).结论中药乙肝散在逆转肝纤维化过程中对抑制肝组织TIMP-1基因表达具有一定作用,TIMP-1在肝纤维化的逆转中起重要作用.  相似文献   
968.
Input-output mathematics, which allows a modeler to fully consider direct and indirect relationships among conserved flows in a system, has a long history in economics with prominent use dating to Leontief in the 1930s. Nearly all previous industrial applications of input-output analysis have been grounded in the monetary flows of an economy. Here however, because of the central nature of physical flows in the environmental impact of industry, we consider physical flows to be a fundamental component of an industrial economy. Hence, we propose an input-output based approach for modeling physical flows in industry independent of their monetary implications.
In this first part of a two-part article, a framework for using input-output mathematics to model material and energy flows is constructed from a foundation laid by previous research in nutrient and energy cycling in natural ecosystems. The mathematics of input-output flow analysis is presented from an ecological perspective, culminating in two core capabilities: tracing of flows with environs (investigated in this article) and characterizing system behavior with flow metrics (presented in the second article). We assert that environ analysis is an effective means for tracing flows through industrial systems while fully considering direct and indirect flow paths. We explore material flows of aluminum and five other metals in depth using environ analysis in this article.  相似文献   
969.
IntroductionAs a consequence of the loss of liver function in chronic liver disease, increased levels of ammonia, manganese, and glutamine have been observed in the brain of hepatic encephalopathy patients.ObjectiveIn the present study, we explored phosphate activated glutaminase (PAG) activity in mitochondrial enriched fractions under treatment with ammonia and manganese.MethodsWe dissected out the brain cortex, striatum, and cerebellum of male Wistar rats 250−280 g weight; brain sections were pooled to obtain enriched mitochondrial fractions by differential centrifugation. Aliquots equivalent to 200 μg of protein were incubated with semi-log increasing concentrations of ammonia and/or manganese both as chloride salts (from 0 to 10 000 μM) and glutamine (4 mM) for 30 min. Then, the glutamate produced by the reaction was determined by HPLC coupled with fluorescence detection.Results and discussionBoth manganese and ammonia inhibited PAG in a concentration-dependent manner. Non-linear modeling was used to determine IC50 and IC20 for ammonia (120 μM) and manganese (2 mM). We found that PAG activity under the combination of IC20 of ammonia and manganese was equivalent to the sum of the effects of both substances, being PAG inhibition more pronounced in mitochondrial fractions from cerebellum. The PAG inhibition observed here could potentially explain a pathway for glutamine accumulation, by means of the inhibition of PAG activity as a consequence of increased concentrations of manganese and ammonia in the brain under liver damage conditions.  相似文献   
970.
Various histone fractions from several sources differ markedly in their degree of dependence on protein kinase stimulatory modulator for maximum phosphorylation by rat liver cyclic GMP-dependent protein kinase in the presence of cyclic GMP. DEAE-cellulose and QAE-Sephadex chromatography of arginine-rich and mixed histones resulted in the histones displaying increased dependence on the modulator. This increased dependence was apparently due to the removal of contaminating modulator as heat-stable modulator activity could be eluted from the DEAE-cellulose column. Lysine-rich histone was not markedly dependent on the modulator before or after QAE-Sephadex chromatography.  相似文献   
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