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1.
β-榄香烯对肝星状细胞周期及凋亡的影响   总被引:7,自引:0,他引:7  
肝纤维化是肝脏细胞外基质(EcM)异常生成和积累的结果,肝星状细胞(hepatic stellate cells,HSC)为肝纤维化形成的关键细胞。HSC在诸多因素(如细胞因子、生长因子、肝细胞、Kupffer细胞、内皮细胞等)的调控下,HSC持续激活导致胶原生成细胞增多,并最终引起ECM的大量沉积,同时在肝纤维化的逆转过程中,HSC的减少主要通过凋亡机制。因此HSC的激活增殖是各种原因引起肝纤维化形成的中心环节,阻抑激活的HSC增殖和诱导其凋亡是治疗慢性肝损伤和肝纤维化的重要策略。莪术为临床抗肝纤维化治疗的常用中药,不少研究显示该药具有抗肝纤维化、抑制ECM生成的作用。榄香烯为其有效成分,具有抗血栓形成、抑制肿瘤细胞增殖、诱导肿瘤细胞凋亡的作用。榄香烯是否为莪术抗肝纤维化的有效成分尚少见报道,本实验采用传代的HSC系HSC-T6初步探讨β-榄香烯对HSC凋亡、增殖的影响。  相似文献   

2.
肝星状细胞(HSC)的增殖与凋亡在肝纤维化的形成缮中起作十分重要的作用.乙醛刺激的HSC增殖是导致酒精性肝纤维化发生的关键因素 [1-2].丝裂原激活蛋白激酶(MAPK)包括细胞外调节蛋白激酶、c-Jun氨基末端激酶和p38,是HSC激活、增殖并导致肝纤维化发生的主要信号传导通路之一,其中,JNK信号传导通路参与了细胞增殖、分化以及凋亡的调控.我们既往对肝纤维化发病机制的研究结果证实,乙醛刺激的HSC中,p-JNK水平随JNK信号传导通路特异阻断剂sp600 125浓度增加而减少[3].  相似文献   

3.
近年来研究表明,肝星状细胞(hepatic stellate cell,HSC)表达的烟酰胺腺嘌呤二核苷酸磷酸氧化酶(NADPH oxidase,NOX)在肝纤维化发病中起关键作用[1].NOX产生的活性氧(reactive oxygen species,ROS)介导了各种促肝纤维化因子在HSC内的信号转导,有望成为抗肝纤维化的新靶点[2].熊果酸(ursolic acid)是从中药植物(如丹参、女贞子等)中提取的单体成分,具有保护肝细胞的作用[3],但其抗肝纤维化作用研究甚少.申月明等[4]在体外研究发现熊果酸能抑制HSC增殖,诱导其凋亡;体内实验证实熊果酸有显著的抗肝纤维化作用[5],但熊果酸抗肝纤维化的作用靶点及机制尚不清楚.Steinkamp-fenske等[6] 报道熊果酸能下调人内皮细胞NOX4的表达并抑制ROS的产生.本实验旨在观察熊果酸对HSC中NOX的影响,以探索熊果酸抗肝纤维化的作用靶点及机制.  相似文献   

4.
在各种治疗肝纤维化的方法中,以肝星状细胞(HSC)为靶点成为目前的研究热点[1-2].国艳等[3]研究发现,莪术油注射液对体外培养的HSC有明显促凋亡作用,但其凋亡机制尚不清楚.我们进一步检测和证实了莪术油注射液对HSC的促凋亡作用;并同时检测促凋亡基因Fas、抑凋亡基因bcl-2与凋亡蛋白酶caspase-3,试图揭示莪术油注射液促进HSC凋亡作用的可能机制.  相似文献   

5.
肝星状细胞(HSC)的活化和增殖是肝纤维化形成的关键环节[1].转化生长因子(TGF)β1可通过HSC内的TGFβ/Smads信号通路促进纤维化的发生发展,被认为是调控肝纤维化的核心物质.抑制TGFβ1合成或其信号传导已证明能拮抗HSC活化与细胞外基质的产生,成为抗肝纤维化的主要目标[2].IL-7是在骨髓中最早发现的一种细胞因子,以往研究证实其能通过上调成纤维细胞Smad7的表达抑制TGFβ/Smads信号通道,具有抗纤维化的作用[3-5].本实验旨在了解IL-7在肝纤维化中的作用,并探讨其作用的分子机制.  相似文献   

6.
缬沙坦对肝纤维化大鼠肝星状细胞凋亡影响的实验研究   总被引:2,自引:0,他引:2  
抑制肝星状细胞(HSC)增殖或促进其凋亡已成为目前治疗肝纤维化的热点.HSC活化是肝纤维化的中心事件.近来发现,血管紧张素Ⅱ(angiotensin Ⅱ,ANG Ⅱ)1型受体(AT1R)拮抗剂有明显抗肝纤维化的作用,但关于其对HSC凋亡的影响少见报道.本研究旨在观察AT1R拮抗剂缬沙坦对大鼠肝纤维化的作用,观察其对HSC凋亡的影响,并探讨其作用机制.  相似文献   

7.
研究证实,肝纤维化的关键细胞--肝星状细胞(hepatic stellate cell,HSC)在活化后表达生长抑素受体(somatostatin receptors,SSTR)[1].而低剂量生长抑素(SST)既能抑制HSC增殖,又能促进其凋亡[2].奥曲肽等SST类似物还具有减少胶原合成的生物学效应[3].因而SST可通过HSC细胞膜上的SSTR介导,在肝纤维化过程中发挥负调节作用.为此,本研究采用四氯化碳(CCl4)诱导大鼠肝纤维化,在此基础上观察不同剂量SST对肝功能、细胞外基质(extracellular matrix,ECM)水平及纤维化程度的干预作用,以期阐明SST对肝纤维化的影响及其机制.  相似文献   

8.
目的观察大黄蔗虫丸对大鼠肝星状细胞活化及增殖的影响。方法用链酶蛋白酶和胶原酶原位灌注消化正常大鼠肝脏,Nycodenz密度梯度离心分离肝星状细胞(HSC),在制备大黄蔗虫丸大鼠药物血清的基础上,温育HSC。MTT比色法测定细胞增殖,流式细胞仪检测细胞凋亡及增殖周期情况。结果药物血清对体外培养的HSC有抑制作用,且存在浓度剂量依赖关系,但作用较弱,需在20%以上方见到显著性差异(P<0.05),对HSC凋亡及细胞增殖周期则无显著影响(P>0.05)。结论大黄蔗虫丸对HSC增殖有一定抑制作用,但可能不是其抗肝纤维化作用的主要途径,其抗肝纤维化作用与诱导细胞凋亡无关。  相似文献   

9.
α干扰素对肝星状细胞凋亡及其基因表达的影响   总被引:9,自引:0,他引:9  
临床研究发现,α干扰素(IFN-α)有特异的抗肝纤维化作用而不依赖于其抗病毒作用,但其抗纤维化机制尚不清楚。目前IFN-α对活化的肝星状细胞(HSC)凋亡的影响未见报道。以体外培养的鼠HSC为研究对象,观察IFN-α对活化状态的HSC凋亡及其相关基因表达的影响  相似文献   

10.
肝纤维化是各种病因引起的肝脏慢性进行性的病理过程,肝纤维化时细胞外基质(ECM)合成大于降解导致ECM在肝内大量沉积。肝星状细胞(HSC)的激活、转化并产生分泌大量ECM是肝纤维化形成的关键环节。而通过诱导活化的HSC发生凋亡是逆转肝纤维化的重要手段之一。就主要的凋亡信号通路:死亡受体通路、线粒体通路、内质网通路、神经生长因子通路进行一一阐述。指出了对活化HSC的凋亡途径进行选择性的药物干预有望发挥抗肝纤维化的作用。  相似文献   

11.
目的胰岛素瘤是最常见的胰腺神经内分泌肿瘤,因其临床表现多样,导致诊断困难。影像学诊断尤其是超声内镜(EUS)在胰岛素瘤的诊断中起着重要作用,拥有较高的敏感性和特异性。本研究拟通过明确胰岛素瘤的解剖分布特点,以期有助于提高影像学的诊断准确率和降低漏诊率,尤其是在教育和培训实践中对于EUS的学习者更具有指导价值。 方法回顾性分析解放军总医院第一医学中心病案资料数据库1993年1月至2019年11月经外科手术、病理确诊为胰岛素瘤的患者的临床资料,检索方法采取搜索术后病理诊断为"胰岛素瘤"的病例,通过查阅病例的方法,提取出胰岛素瘤的大小和解剖分布等数据,进一步分析其特点。 结果共检索到确诊为胰岛素瘤的患者116例,其中,男45例、女71例,年龄13~76岁,平均年龄(44.4±14.85)岁。胰岛素瘤单发110例(94.8%)、多发6例(5.2%)。位置分布:头颈部46例(39.7%),单发45例、多发1例;体尾部68例(58.6%),单发65例、多发3例;全胰腺多发2例(1.7%)。病变大小特点:最大径0.4~3.4 cm,平均大小(1.53±0.58)cm。≤1 cm 29例、>1 cm而≤1.5 cm41例、>1.5 cm而≤2.0 cm28例,≤3 cm 15例,>3 cm 3例。年龄与肿瘤的大小相关,≤44岁患者肿瘤平均大小为(1.36±0.51)cm、>44岁患者肿瘤平均大小为(1.70±0.60)cm,P<0.05。头颈部的肿瘤大于体尾部的肿瘤,头颈部肿瘤平均大小(1.66±0.63)cm,体尾部(1.42±0.52)cm,P<0.05。 结论胰岛素瘤在胰腺体尾部较头颈部更好发;绝大多数单发,但可以全胰腺多发;多数小于1.5 cm,肿瘤的大小与患者年龄和肿瘤的解剖分布相关。  相似文献   

12.
Most adenomas and carcinomas of the small intestine and extrahepatic bile ducts arise in the region of the papilla of Vater. In familial adenomatous polyposis (FAP) it is the main location for carcinomas after proctocolectomy. In many cases symptoms due to stenosis lead to diagnosis at an early tumor stage. In about 80%, curative intended resection is possible. Operability is the most relevant prognostic factor. Most ampullary carcinomas resp. carcinomas of the papilla of Vater develop from adenomatous or flat dysplastic precursor lesions. They can be sited in the ampulloduodenal part of the papilla of Vater, which is lined by intestinal mucosa. They also can develop in deeper parts of the ampulla, which are lined by pancreaticobiliary duct mucosa. Intestinal-type adenocarcinoma and pancreaticobiliary-type adenocarcinoma represent the main histological types of ampullary carcinoma. Furthermore, there exist unusual types and undifferentiated carcinomas. Many carcinomas of intestinal type express the immunohistochemical marker profile of intestinal mucosa (keratin 7?, keratin 20+, MUC2+). Carcinomas of pancreaticobiliary type usually show the immunohistochemical profile of pancreaticobiliary duct mucosa (keratin 7+, keratin 20?, MUC2?). Even poorly differentiated carcinomas, as well as unusual histological types, may conserve the marker profile of the mucosa they developed from. These findings underline the concept of histogenetically different carcinomas of the papilla of Vater which develop either from intestinal- or from pancreaticobiliary-type mucosa of the papilla of Vater. Molecular alterations in ampullary carcinomas are similar to those of colorectal as well as pancreatic carcinomas, although they appear at different frequencies. In future studies, molecular alterations in ampullary carcinomas should be correlated closely with the different histologic tumor types. Consequently, the histologic classification should reflect the histogenesis of ampullary tumors from the two different types of papillary mucosa.  相似文献   

13.
Summary Palmitic acid oxidation in rat diaphragm homogenate is depressed by biguanide concentrations that are still incapable of inhibiting oxidative phosphorylation. Glucose oxidation is not directly effected by the same biguanide concentrations: however, the inhibitory effect of palmitic acid on glucose oxidation is partly removed by biguanides. Inhibition of fatty acid oxidation, which accounts for most of the metabolic effects caused by these drugs, can be regarded as the fundamental mechanism of action of biguanides. There is some evidence suggesting that these drugs might interact with carnitine, thus preventing long-chain fatty acids from being transported across the mitochondrial membrane to the site of oxidation. Traduzione a cura degli AA.  相似文献   

14.
BACKGROUND AND AIM: Both the clinical presentation and the degree of mucosal damage in coeliac disease vary greatly. In view of conflicting information as to whether the mode of presentation correlates with the degree of villous atrophy, we reviewed a large cohort of patients with coeliac disease. PATIENTS AND METHODS: We correlated mode of presentation (classical, diarrhoea predominant or atypical/silent) with histology of duodenal biopsies and examined their trends over time. RESULTS: The cohort consisted of 499 adults, mean age 44.1 years, 68% females. The majority had silent coeliac disease (56%) and total villous atrophy (65%). There was no correlation of mode of presentation with the degree of villous atrophy (p=0.25). Sixty-eight percent of females and 58% of males had a severe villous atrophy (p=0.052). There was a significant trend over time for a greater proportion of patients presenting as atypical/silent coeliac disease and having partial villous atrophy, though the majority still had total villous atrophy. CONCLUSIONS: Among our patients the degree of villous atrophy in duodenal biopsies did not correlate with the mode of presentation, indicating that factors other than the degree of villous atrophy must account for diarrhoea in coeliac disease.  相似文献   

15.
血吸虫童虫是宿主免疫系统攻击的重要靶标,包括皮肤型、肺型和肝门型童虫。宿主分子对童虫生长发育具有重要作用。童虫生长发育机制包括免疫调节、信号转导、性别发育及凋亡等。肌动蛋白、组织蛋白酶、烯醇化酶和葡萄糖基转移酶等分子为血吸虫童虫生长发育的重要分子。本文对血吸虫童虫生长发育及其机制的研究进展做一综述。  相似文献   

16.
氯硝柳胺悬浮剂的毒性评价   总被引:2,自引:2,他引:2  
目的评价氯硝柳胺悬浮剂的毒性,为现场大规模应用灭螺提供依据。方法按照中华人民共和国国家标准GB 15670-1995《农药登记毒理学试验方法》和鱼类毒性试验方法进行。结果经口、经皮肤的LDso雌、雄性大鼠均>5 000 mg/kg,经呼吸道的LCso雌、雄性大鼠均>5 000mg/m3,该药经口、经皮肤、经呼吸道毒性均属微毒类药物;兔眼用药后,观察期内无不良反应,对眼无刺激性;皮肤用药后对皮肤无刺激性。与氯硝柳胺原药、氯硝柳胺乙醇胺盐原药和氯硝柳胺乙醇胺盐可湿性粉剂相比,氯硝柳胺悬浮剂对鱼急性毒性最低。结论氯硝柳胺悬浮剂属微毒类药物,对鱼的毒性低于其乙醇胺盐可湿性粉剂,适合于现场应用。  相似文献   

17.
目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。  相似文献   

18.
The aim of the study was to assess the quality of life (QOL) and the psychological status of parents of children with juvenile chronic arthritis (JCA). The QOL, anxiety and depression of the parents of 28 children with JCA were evaluated and compared to those of the parents of 28 healthy children. Mothers of JCA children and mothers of healthy children reported similar QOL. The reported anxiety and depression levels were similar for mothers and fathers in both groups. The parents of children with pauciarticular-type JCA reported lower QOL and higher levels of anxiety and depression than the parents of children with other types, namely polyarticular and systemic JCA. These findings may be explained by the fact that the pauciarticular patients had shorter disease duration and were less frequently seen in the outpatient clinic. The QOL of mothers of children with JCA was found to be slightly impaired in the group of children with pauciarticular JCA. Future larger studies are needed to confirm these results, as the number of subjects in the three groups was rather low. Received: 26 September 2001 / Accepted: 8 February 2002  相似文献   

19.

Background

A 5-day in-patient study designed to assess the accuracy of the FreeStyle Navigator® Continuous Glucose Monitoring System revealed that the level of accuracy of the continuous sensor measurements was dependent on the rate of glucose change. When the absolute rate of change was less than 1 mg•dl−1•min−1 (75% of the time), the median absolute relative difference (ARD) was 8.5%, with 85% of all points falling within the A zone of the Clarke error grid. When the absolute rate of change was greater than 2 mg•dl−1•min−1 (8% of the time), the median ARD was 17.5%, with 59% of all points falling within the Clarke A zone.

Method

Numerical simulations were performed to investigate effects of the rate of change of glucose on sensor measurement error. This approach enabled physiologically relevant distributions of glucose values to be reordered to explore the effect of different glucose rate-of-change distributions on apparent sensor accuracy.

Results

The physiological lag between blood and interstitial fluid glucose levels is sufficient to account for the observed difference in sensor accuracy between periods of stable glucose and periods of rapidly changing glucose.

Conclusions

The role of physiological lag on the apparent decrease in sensor accuracy at high glucose rates of change has implications for clinical study design, regulatory review of continuous glucose sensors, and development of performance standards for this new technology. This work demonstrates the difficulty in comparing accuracy measures between different clinical studies and highlights the need for studies to include both relevant glucose distributions and relevant glucose rate-of-change distributions.  相似文献   

20.
Angiography using Prostaglandin El® was performed on 38 patients with carcinoma of the colon in order to diagnose the degree of serosal cancer invasion. The findings at angiography were classified into four groups:1) AG-S3, abnormal change (irregularity and/or encasement) up to marginal vessels; 2) AG-S2, abnormality up to vasa recta; 3) AG-S1, abnormality of penetrating branches of vasa recta within the wall of the colon; and 4) AG-S0, no distinct findings of abovementioned vessels. These angiographic findings were compared with both macroscopic and microscopic serosal cancer invasion. Angiographic diagnosis is in accord with the macroscopic findings in 84.2 percent of cases. Angiographic diagnosis is in accord with the microscopic findings in 32.4 percent of cases. Macroscopic findings confirm the angiographic diagnosis precisely but the conflict with microscopic findings should not be overlooked. This may be the result of inflammatory change, adhesion, and fibrosis around carcinoma of the colon.  相似文献   

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