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目的 观察Ⅱ型胶原在T-2毒素诱导大鼠关节软骨早期损伤中的干预作用,在分子水平上寻找软骨损伤及修复的分子学生物标志,为探讨关节软骨损伤疾病的防治措施提供理论依据.方法 Wistar大鼠80只,按体质量随机分为4组:阴性对照组、阳性对照组、高剂量干预组、低剂量干预组,每组20只.阴性对照组食用常规成品颗粒饲料,其他3组食用含100 ng/kg T-2毒素染毒饲料;阴性对照组和阳性对照组饮自来水;低、高剂量干预组饮用含Ⅱ型胶原0.5、5.0 g/L的自来水.在3、5个月时处死大鼠,光镜下观察大鼠透明软骨的组织病理学改变,用酶联免疫吸附试验(ELISA法)检测大鼠血清Ⅱ型胶原羧基末端肽(CTX-Ⅱ)、软骨寡聚基质蛋白(COMP)及尿中吡啶啉(DPD)含量.结果 光镜下阳性对照组大鼠关节软骨细胞排列紊乱,软骨细胞变形、变性,可见大面积的软骨细胞坏死,而高、低剂量干预组表现为软骨表面原纤维形成,表层软骨细胞肿胀变圆,扁平的软骨细胞减少,软骨细胞簇集等骨关节炎早期病理改变.在3、5个月时,阴性对照组、阳性对照组、高剂量干预组、低剂量干预组大鼠血清CTX-Ⅱ含量分别为(18.77±4.61)、(25.07±9.17),(24.43±5.23)、(39.17±10.49),(21.11±5.02),(33.20±9.74),(19.87±4.53)、(29.73±9.32)μg/L;血清COMP含量分别为(5.43±2.75)、(6.38±2.23),(21.37±4.72)、(24.52±4.26),(17.27±4.77)、(20.32±4.74),(20.13±5.07)、(19.44±4.92)μg/L.其中,3个月时,与阴性对照组比较,阳性对照组血清CTX-Ⅱ含量明显升高(P<0.05),而低、高剂量干预组未见明显改变(P均> 0.05);5个月时,与阴性对照组比较,其他3组血清CTX-Ⅱ含量明显升高(P均< 0.05),而高、低剂量干预组明显低于阳性对照组(P均<0.05).3个月时,与阴性对照组比较,其他3组血清COMP含量明显升高(P均<0.05),而与阳性对照组比较,高剂量干预组血清COMP含量明显降低(P<0.05);5个月时,与阴性对照组比较,其他3组血清COMP含量明显升高(P均<0.05),而与阳性对照组比较,高、低剂量干预组血清COMP含量明显降低(P均<0.05).3、5个月时,上述4组大鼠尿液DPD含量分别为( 3.47±2.20)、(4.14±1.06),(4.09±2.48)、(4.33±3.43),(3.86±2.31)、(5.72±3.89),(3.58±2.77)、(4.23±2.90)μg/L,组间比较,差异无统计学意义(F值分别为2.608、2.436,P均>0.05).结论 Ⅱ型胶原能拮抗T-2毒素的软骨损伤作用,延缓关节软骨的破坏进程,降低大鼠血清中CTX-Ⅱ及COMP水平. 相似文献
114.
内皮脂酶是近年来发现的甘油三酯脂肪酶基因家族新成员.该家族还包括脂蛋白脂肪酶、肝脂肪酶.内皮脂酶具有磷脂酶活性,可参与脂蛋白代谢,尤其对血浆中的高密度脂蛋白代谢及高密度脂蛋白胆固醇水平具有明显调节作用.近来研究证明,抑制内皮脂酶可提高人血浆高密度脂蛋白胆固醇水平.但目前内皮脂酶与高密度脂蛋白胆固醇、胆固醇逆行转运及动脉粥样硬化之间的关系仍尚无明确定论,且有待进一步研究. 相似文献
115.
This study was performed to determine the risk of family members of anti-hepatitis C virus (HCV)-positive hemophilia patients (index patients) for infection with HCV compared with the risk of acquiring hepatitis B virus (HBV), human immunodeficiency virus (HIV), and hepatitis A virus (HAV) infection. All index patients (n = 141) were found to be positive by first and second generation anti-HCV enzyme immunoassays (EIAs). Among their household contacts (n = 228), 224 were negative and 1 positive by both assays. Three contacts gave positive results in first generation anti-HCV EIA and negative results in second generation assay. This latter result was confirmed by further tests (neutralization test, synthetic peptides, and supplemental assay). Percent positivity for anti-HBc was about the same in non-sexual household contacts and sexual partners (13 of 109 [12%] and 7 of 54 [13%], respectively). Percent prevalence of anti-HBc was higher in contacts of index patients with chronic hepatitis B than in those of index patients who had recovered from that disease (6 of 20 [30%] and 14 of 133 [10%], respectively; P < .05). The HBV infection rate of contacts participating in controlled self-treatment was not higher than that of controls (3 of 57 [5%] and 10 of 98 [10%], respectively). Of 44 sexual partners, 5 (11%) were found to be positive for anti-HIV. Prevalence of anti-HAV matched with the age-related distribution in the German population. These findings suggest that intrafamilial transmission of HCV to family members of hemophilia patients is uncommon. In contacts of hemophilia patients, the risk of acquiring HBV infection seems to be as high in household contacts as in sexual contacts. Participation in controlled self-treatment does not appear to be an additional risk for HCV and HBV infection. There is no doubt that sexual transmission of HCV is less common than that of HBV and HIV. 相似文献
116.
Muhammed AM Suliman Fawzy MH Khalil Salam SA Alkindi Anil V Pathare Ali AA Almadhani Neveen AAI Soliman 《World journal of gastrointestinal pathophysiology》2012,3(5):92-98
AIM: To evaluate the role of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in cirrhotic patients who have hepatic and renal impairment with spontaneous bacterial peritonitis (SBP).METHODS: We prospectively studied 120 cirrhotic patients with SBP and 80 cirrhotic patients with sterile ascitic fluid. They included 144 males and 56 females with ages ranging between 34 and 62 years. The diagnosis of cirrhosis was established by clinical and laboratory criteria that did not require histological confirmation. The severity of underlying liver disease was evaluated using Pugh’s modification of Child’s criteria (Child-Pugh scores). Ascitic fluid was sent to the laboratory for cell count, culture, sensitivity testing, and measurement of chemical elements (i.e., albumin, glucose). Specimens were inoculated into aerobic and anaerobic blood culture bottles. Serum and ascitic fluid were also collected in sterile tubes at study entry (before the initiation of antibiotic treatment) and 48 h later. Assays for TNF-α and IL-6 in the serum and ascitic fluid were performed with an immunoenzymometric assay using manufacture’s instructions.RESULTS: Cytokine levels in serum and ascitic fluid were significantly higher in the patients with SBP. (plasma TNF-α: 135.35 ng/mL ± 11.21 ng/mL vs 92.86 ng/mL ± 17.56 ng/mL, P < 0.001; plasma IL-6: 32.30 pg/mL ± 7.07 pg/mL vs 12.11 pg/mL ± 6.53 pg/mL, P < 0.001; ascitic fluid TNF-α: 647.54 ± 107.11 ng/mL vs 238.43 ng/mL ± 65.42 ng/mL, P < 0.001); ascitic fluid IL-6: 132.84 ng/mL ± 34.13 vs 40.41 ± 12.85 pg/mL, P < 0.001). About 48 (40%) cirrhotic patients with SBP developed renal and hepatic impairment and showed significantly higher plasma and ascitic fluid cytokine levels at diagnosis of infection. [(plasma TNF-α: 176.58 ± 17.84 vs 135.35 ± 11.21 ng/mL) (P < 0.001) and (IL-6: 57.83 ± 7.85 vs 32.30 ± 7.07 pg/mL) (P < 0.001); ascitic fluid TNF-α: 958.39 ± 135.72 vs 647.54 ± 107.11 ng/mL, (P < 0.001), ascitic fluid IL-6: 654.74 ± 97.43 vs 132.84 ± 34.13 pg/mL, (P < 0.001)]. Twenty nine patients (60.4%) with SBP and renal impairment died whereas, only four patients (5.55%) with SBP but without renal impairment died from gastrointestinal hemorrhage (P < 0.0005).CONCLUSION: It appears that TNF-α production may enhance liver cell injury and lead to renal impairment. This correlated well with the poor prognosis and significantly increased mortality associated with SBP in cirrhotic patients. 相似文献
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PR Hunziker S Smith M Scherrer-Crosbie N Liel-Cohen RA Levine R Nesbitt SA Benton MH Picard 《Circulation》1999,99(5):1-6
Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging. 相似文献
119.
目的分析物种差异与肠道形态及能量代谢的关系,阐明长爪沙鼠的能量需求。方法长爪沙鼠、SD大鼠、ICR小鼠各10只,分别单独饲养于代谢笼内,收集5 d动物24 h内的粪便、尿液。尿液及粪便经分别测量体积与重量后,送检尿能与粪能。收集结束后,所有动物称重,麻醉后腹主动脉采血致死,取动物肠道,测量肠长度。结果大鼠维持的消化能和代谢能分别为314.56 k J/d、314.55 k J/d,小鼠分别为10.608 k J/d、9.799 k J/d,沙鼠分别为99.828 k J/d、99.927 k J/d。大鼠每增加1 g体重需要的消化能和代谢能分别是19.273 k J和18.831 k J,小鼠分别是71.842 k J和72.390 k J,沙鼠分别是56.142 k J和55.965 k J。大、小鼠的消化道总长大于沙鼠,大鼠小肠最长,而沙鼠有较大的盲肠百分比。结论三种动物在肠道长度和能量需求方面有显著差异。 相似文献
120.
It has previously been shown that monolayer cultures derived adherent cells (MDAC), apparently consisting of fibroblasts, macrophages, epithelioid cells, and fat cells, can support long-term stem cell proliferation in vitro. In the present study, the hematopoietic support capability of murine MDAC monolayers was confirmed and the cultured cells further characterized with respect to the following properties: esterase I activity, complement (C3) receptors, IgG (Fc) receptors, colony stimulating activity (csa) production, and collagen synthesis. The cultures were also examined immunohistochemically to localize fibronectin, laminin, and collagen synthesis and to identify the collagen subtypes synthesized. MDAC morphology was as described in previous studies, although fat cells were few in number. It was found that MDAC included some cells with esterase I activity and C3 receptors. Fc receptors were not, however, detected, nor did the cultures produce csa, indicating that mononuclear phagocytes were not present. MDAC synthesized collagen types I and III and also fibronectin. Staining for epithelial basement membrane proteins (collagen types IV and V and laminin) was negative. The results indicate that the vast majority of these cultured MDAC were fibroblasts. 相似文献