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81.
Harvey Wong Lois D Lehman-McKeeman Mary F Grubb Scott J Grossman Vasanthi M Bhaskaran Eric G Solon Helen S L Shen Ronald J Gerson Bruce D Car Bitao Zhao Brian Gemzik 《Toxicological sciences》2005,84(2):232-242
4-(3-pentylamino)-2,7-dimethyl-8-(2-methyl-4-methoxyphenyl)-pyrazolo-[1,5-a]-pyrimidine (DMP 904) is a potent and selective antagonist of corticotropin releasing factor receptor-1 (CRF1 receptor) with an efficacious anxiolytic profile in preclinical animal models. In subchronic toxicity studies in Sprague-Dawley rats, DMP 904 produced thyroid follicular cell hypertrophy and hyperplasia, and a low incidence of follicular cell adenoma. The current investigations were designed to determine the mode of action by which DMP 904 disrupts thyroid homeostasis in male rats. Five-day treatment with DMP 904 (300 mg/kg/day) dramatically lowered serum thyroxine (T4) to levels below detectable limits (< 1 microg/dl) by 72 h, with concurrent decreases in triiodothyronine (T3, about a 70% decrease) and increases in thyroid stimulating hormone (TSH; about a three-fold increase). DMP 904 increased [125I]T4 total body clearance (Cl tb) (38.21 +/- 10.45 ml/h) compared to control (5.61 +/- 0.59 ml/h) and phenobarbital-treated rats (7.92 +/- 1.62 ml/h). This increase in Cl(tb) was associated with a significant increase in biliary clearance (Cl bile) of unconjugated [125I]T4 (nearly 80-times control rates) and increased liver:blood ratios of T4, suggestive of enhanced hepatic uptake of T4. A single dose of DMP 904 (200 mg/kg) increased mRNA levels of hepatic cytochrome P450s (CYP 3A1 and CYP 2B1) and UDP-glucuronosyltransferases (UGT 1A1 and UGT 1A2). DMP 904 also induced mRNAs of the canalicular transporter, multi-drug resistance protein-2 (Mrp2) and sinusoidal transporters, organic anion transporting proteins (Oatp1 and Oatp2) within 24 h. Western blot analysis confirmed DMP 904 related increases in Oatp2 protein expression. Collectively, these data suggest that DMP 904 is an agonist of the constitutive androstane receptor (CAR) and pregnane X receptor (PXR) and that the decreased serum levels of T4 and T3 resulted from increased hepatobiliary clearance. However, DMP 904 is distinguished from other compounds associated with similar effects on thyroid hormone homeostasis because its effects were primarily related to increased biliary excretion of unconjugated T4. 相似文献
82.
反义DNMT1、DNMT3b基因真核表达载体联合转染对人胆管癌细胞增殖和凋亡的影响 总被引:1,自引:0,他引:1
目的观察联合转染反义DNMT1、DNMT3b基因真核表达载体对人胆管癌细胞株QBC-939的增殖能力和细胞凋亡的影响。方法分别构建反义DNMT1基因和反义DNMT3b基因真核表达载体,脂质体介导法将二者先后转染入QBC-939,经G418筛选和荧光细胞克隆挑选得到稳定转染细胞株,并用Western blot检测转染前后的蛋白表达变化;用MTT法和软琼脂克隆形成试验观察各组细胞的增殖能力,流式细胞术检测细胞生长周期及凋亡率的变化。结果Western blot检测证实转染反义基因能使相应蛋白表达水平降低;联合转染反义DNMT1、DNMT3b基因和单独转染反义DNMT1基因能影响QBC-939的生长曲线,使细胞增殖减慢,并以前者为甚;联合转染反义DNMT1、DNMT3b基因和单独转染反义DNMT1基因的细胞克隆形成率分别为(6.78±0.89)%和(14.86±2.13)%,明显低于未转染组;联合转染反义DNMT1、DNMT3b基因和单独转染反义DNMT1能影响QBC-939的细胞周期,使之阻滞于G1期,细胞凋亡率从(1.63±0.27)%分别增加到(18.47±1.46)%和(6.19±0.78)%;在上述效应检测中,单独转染反义DNMT3b基因实验组对QBC-939细胞的生长无明显影响。结论通过联合转染反义DNMT1和DNMT3b基因真核表达载体,能抑制胆管癌细胞的生长和增殖,并促进凋亡的发生,其效果明显优于单独转染DNMT1反义基因;在DNA甲基化的过程中,DNMT1起着主要的作用,DNMT3b扮演着协同的角色,二者通过甲基化途径对胆管癌的发生发挥作用。 相似文献
83.
Methylenedianiline (DAPM) rapidly injures biliary epithelial cells (BEC) in vivo. Prior to evident BEC injury, biliary glucose and inorganic phosphate appreciably rise, which could stem from loosened tight junctions (TJ). Concurrently, ultrastructural abnormalities in BEC mitochondria of DAPM-treated animals are observed, suggesting other impairments. Our objective was to develop an in vitro BEC model to assess the time course of impairments in TJ integrity, glucose uptake, and mitochondrial function following DAPM exposure. We exposed monolayers of primary, polarized rat BEC to bile collected from rats prior to (Basal Bile) or after oral treatment (DAPM-Bile) with 50 mg DAPM/kg. DAPM-Bile collected during 0-60 min (1st Hr) and during 61-120 min (2nd Hr) after treatment was pooled from four to six rats. When monolayers were exposed to 1st Hr DAPM-Bile for 120 min, metabolic activity (XTT assay) decreased approximately 75%, and transepithelial resistance decreased approximately 16% in agreement with an approximately 65% increase in leakage of a glucose analog, methyl-alpha-D-glucopyranoside (AMG), from apical to basolateral media. By 60 min, AMG uptake was decreased approximately 40%. Mitochondrial function was very rapidly compromised, with approximately 120% increases in the green-to-red fluorescence ratio of JC-1 (mitochondrial membrane potential dye) at 15 min and approximately 55% decreases in ATP levels at 30 min. This sequence of events indicates that DAPM impairs BEC mitochondria prior to impairments in glucose uptake or TJ integrity. Thus, our in vitro primary rat BEC/bile exposure model mimics in vivo observations and yields basic information about the time course of events that occur during DAPM-induced injury. 相似文献
84.
Complications from improperly placed biliary stents are not uncommon. Free loose wires from the ends of an uncovered stent can irritate and damage adjacent mucosal surfaces. Effective management can be achieved via percutaneous placement of a second stent to alter the orientation of the original stent. 相似文献
85.
中药治疗原发性胆汁性肝硬化引起的皮肤瘙痒2例 总被引:2,自引:0,他引:2
皮肤瘙痒是原发性胆汁性肝硬化临床常见症状之一,通过中医辨证施治,以养血润燥、祛风止痒法,或利湿退黄、祛风止痒法,有一定疗效。并举验案2则佐证。 相似文献
86.
原发性胆汁性肝硬化患者外周血APRIL基因表达水平初探 总被引:4,自引:2,他引:2
目的 建立检测人增殖诱导配体(APRIL)mRNA的实时荧光定量PCR方法,探讨外周血单个核细胞APRIL mRNA表达水平与原发性胆汁性肝硬化(PBC)的相关性。方法 采用实时荧光定量PCR法检测30例正常人和40例PBC患者外周血单个核细胞(PBMC)APRIL基因的相对表达量,以Ct值比较法计算APRIL基因相对表达水平。结果 PBC患者外周血单个核细胞APRIL mRNA的△Ct值为9.3±2.0,与正常对照组比较.差异显著(P〈0.05)。采用2^-△△Ct法进行数据分析后,PBC组APRIL mRNA相对表达量比正常对照组高3.5倍。PBC患者中抗核抗体(ANA)阳性占80%,其中荧光模式为核膜型19例。其他型13例(着丝点型10例,混合型3例),其APRIL基因相对表达量比正常对照组高6.5和1.7倍。结论 PBC患者外周血单个核细胞APRIL mRNA表达水平显著升高,且与ANA荧光模式相关。 相似文献
87.
目的探讨胆道手术不进行预防性腹腔引流的临床效果。方法将胆道手术患者随机分为观察组与对照组。观察组:不放引流管,针对导致术后出血、胆汁性腹膜炎、胆瘘等常见并发症的原因予以处理;对照组:术中安放引流管,其他处理同观察组。术后比较两组患者的临床疗效、引流副作用、住院时间、住院费用等。结果两组患者均痊愈出院。观察组平均住院时间及住院费用明显少于对照组(t=11.72,9.22;P<0.01);对照组的引流副作用发生率为31.03%,观察组则没有,二者比较有统计学意义(χ2=33.62,P<0.01)。结论胆道手术是否安放预防性腹腔引流应视术中对易致并发症部位的处理情况确定,绝大部分患者是可以不安放腹腔引流的。 相似文献
88.
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90.
Three infants with anterior abdominal wall defects (gastroschisis and exomphalos) who presented with obstructive jaundice secondary to biliary obstruction, are described. All three infants had abnormal biliary systems, with mechanical distortion of the biliary tree. Biliary obstruction secondary to structural biliary anomalies should be considered in patients with abdominal wall defects and cholestasis, as prolonged unrelieved biliary obstruction may lead to biliary cirrhosis and portal hypertension. 相似文献