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51.
Andrea N. Bell Robert A. Young Virginia G. Lockard Harihara M. Mehendale 《Archives of toxicology》1988,61(5):392-405
Chlordecone (CD) pretreatment is known to markedly potentiate CCl4 hepatotoxicity. Previous studies have shown that prior exposure to CD obtunds the increased hepatocellular regeneration and repair observed in non-treated rats challenged with a single, low dose of CCl4. These observations allowed us to hypothesize that suppression of hepatic regeneration and tissue repair by CD + CCl4 combination treatment might be involved in this interaction. To test this hypothesis, CCl4 hepatotoxicity was evaluated in actively regenerating livers using CD-treated (10 ppm in the diet for 15 days), surgically partially hepatectomized (PH) male Sprague-Dawley rats. Rats undergoing no surgical manipulation (CTRL) and sham operation (SH) were included as appropriate controls. Surgical manipulations were conducted on day 15 of the dietary protocol. Based on liver-to-body weight ratios (LW/BW), mitotic indices, hepatic cytochrome P-450 content, and hepatic glutathione (GSH and GSSG) levels, PH-induced hepatocellular regeneration was not affected by pretreatment with CD. Thus, the PH model was considered valid for assessing the effects of CD + CCl4 combination treatment. CCl4 (100 l/kg; i.p.) was administered 1, 2, 4 or 7 days after the surgical manipulations. Hepatotoxicity was assessed 24 h later by measuring LW/BW and serum enzymes (SGPT, SGOT and ICD) in all four groups. Hepatic histopathological, histomorphometric and lethal effects were assessed in animals receiving CCl4 1 or 7 days after the surgical manipulations. CCl4-induced increases in LW/BW were observed in CD + PH rats receiving CCl4 4 or 7 days post-PH, but not in the 1 or 2 day post-PH groups in which the hepatocellular regeneration was maximal. CCl4-induced serum enzyme elevations were significantly less in the CD + PH rats as compared to CD + SH. This decrease in the serum enzyme elevations was most prominent in the 1 day post-PH group, where the hepatocellular mitotic activity was most pronounced. CCl4 lethality, assessed in the 1 day post-surgical manipulation group, was also decreased in the CD + PH rats in comparison to CD + SH rats. Such a protection was not observed in rats receiving CCl4 7 days post-PH. These data are consistent with and are supportive of the hypothesis that a suppression of otherwise normally stimulated hepatocellular regeneration following low-dose CCl4 administration is involved in the marked amplification of CCl4 toxicity by CD.Abbreviations CD
chlordecone
- GSH
reduced glutathione
- GSSG
oxidized glutathione
- PH
partial hepatectomy
- SH
shamhepatectomy
- CTRL
control, not surgically manipulated
- N
normal diet
- LW/BW
liver weight-to-body weight ratio
- SGPT
serum glutamic; pyruvic transaminase
- SGOT
serum glutamic oxaloacetic transaminase
- ICD
isocitrate dehydrogenase
These studies were made possible by a grant from the US Environmental Protection Agency R-811072A preliminary report of these findings was presented at the 70th Annual Meetings of the Federation of American Societies for Experimental Biology at St. Louis, MO (Fed Proc 45: 1051, 1986)A. N. Bell is a Predoctoral Toxicology Trainee and Robert A. Young is a Postdoctoral Trainee supported by Toxicology Training grant from National Institute of Environmental Health Science ES-07045 相似文献
52.
目的:探讨超声造影(CEUS)技术在腹腔镜T1期肝细胞癌(HCC)切除术中的应用价值。方法:选择2018年1月—2020年12月于天津医科大学第二医院行腹腔镜T1期HCC切除术的患者80例,根据是否行术前CEUS将患者分为造影组和对照组(每组40例)。均在距肿瘤边缘0.5 cm处切开患者肝脏实质并完整切除肿瘤,然后在切缘3个不同位置取组织活检。采用免疫组化检测癌组织中增殖细胞核抗原(PCNA)及Bcl-2相关X蛋白(Bax)的表达水平。记录患者手术时间、术中出血量、住院时间、肿瘤直径、切缘长度、术后进食时间、拔除引流管时间、术后最高丙氨酸氨基转移酶(ALT)和总胆红素(TBIL)及其恢复正常时间。术后均行规律随访观察。结果:与对照组相比,造影组手术时间(t=11.69,P<0.001)及住院时间更短(t=9.40,P<0.001),术中出血量更少(t=14.86,P<0.001);而两组患者在肿瘤直径(t=0.28,P=0.78)、切缘长度(t=0.18,P=0.86)、术后进食时间(t=0.44,P=0.66)及拔除引流管时间(t=1.16,P=0.25)方面差异均... 相似文献
53.
Choremi-Papadopoulou H Tsalimalma K Dafni U Dimitracopoulou A Kordossis T 《Journal of medical virology》2004,73(2):235-243
Long-term (3.5 years) immune reconstitution in relation to viral load response was determined. Plasma HIV-1 RNA was suppressed in 40 patients (full responders) up to 42 months, and 17 patients achieved partial response. The measurements of CD4+ and CD8+ T lymphocyte subsets (CD45RA, CD45RACD62L, CD45RO, CD28, CD38) were carried out by flow cytometry. Full responders had a significant increase of CD4+ and all CD4+ T subsets both up to 6 and from 6 to 42 months, while the increase for partial responders was only up to 6 months. By 6 months, higher slopes were observed in full versus partial responders in the % of CD28 on CD4+ and the % of CD4+ memory subset and in both naïve and memory CD4+ subsets from 6 to 42 months. The percentage of CD8+ and its subsets was decreased significantly in full responders both up to 6 and from 6 to 42 months (except for an increase in the CD8+CD45RA+ CD62L+ cells), while in partial responders this decrease was only up to 6 months. Lower slopes were observed in full versus partial responders from 6 to 42 months in the percentages of CD8+, CD8+CD45RO+, CD8+CD28−, and CD8+CD38+ T cells. In conclusion, full responders have a stronger long-term naive CD4+ T cell subset reconstitution than partial responders. J. Med. Virol. 73:235–243, 2004. © 2004 Wiley-Liss, Inc. 相似文献
54.
Nwosu E.C.; Ferriman E.; McCormack M.J.; Williams J.H.; Gosden C.M. 《Human reproduction (Oxford, England)》1995,10(9):2459-2462
Partial hydatidiform mole associated with live births is a rarecondition. There are not enough cases in the literature to allowthe assessment of comprehensive risks to be made and upon whichmanagement policies can be based. Several clinical dilemmasarise following diagnosis of a viable pregnancy associated withmolar tissue. We present two cases demonstrating the problemsand suggest management based on outcome and a review of theliterature. 相似文献
55.
目的了解糖类代谢相关基因在大鼠肝再生中的表达变化。方法本研究用搜集网站资料和查阅相关论文等方法获得糖类代谢相关基因,用大鼠基因组230 2.0芯片检测它们在大鼠再生肝中的表达情况,用比较手术组和假手术组中基因表达的差异性确定肝再生相关基因。结果初步证实上述基因中118个基因与肝再生相关。肝再生早期[部分肝切除(PH)后0.5~4h]、前期(PH后4~12h)、中期(PH后16~66h)和后期(PH后72~168h)等4个阶段起始表达的基因数为33、6、68和7;基因的总表达次数为68、44、210和83。表明肝再生相关基因主要在肝再生启动阶段起始表达,在不同阶段发挥作用。它们共上调205次,下调200次,分为12种表达方式,表明肝再生中糖代谢活动多样和复杂。其中,单糖和糖原代谢、糖蛋白和糖脂(主要为神经节苷脂)合成相关基因几乎在整个肝再生中表达增强,寡糖和糖胺聚糖合成及糖蛋白和糖脂分解相关基因表达下调。结论肝再生与糖代谢密切相关。 相似文献
56.
T. V. Osipova V. M. Bukhman G. Ya. Svet-Moldavskii 《Bulletin of experimental biology and medicine》1978,85(2):221-222
Two thirds of the liver was removed from (CBA×C57BL/6j)F1 female mice. On the 5th day after the operation a significant increase was observed in the number of endogenous colonies in the spleen of the partially hepatectomized animals. This increase was not connected with a change in the number of stem cells in the bone marrow, for partial hepatectomy at different times after the operation did not affect the number of colony-forming units in the bone marrow.Laboratory of Virology, Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Kraevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 218–219, February, 1978. 相似文献
57.
We develop tidal-ventilation pulmonary gas-exchange equations that allow pulmonary shunt to have different values during expiration and inspiration, in accordance with lung collapse and recruitment during lung dysfunction (Am. J. Respir. Crit. Care Med. 158 (1998) 1636). Their solutions are tested against published animal data from intravascular oxygen tension and saturation sensors. These equations provide one explanation for (i) observed physiological phenomena, such as within-breath fluctuations in arterial oxygen saturation and blood-gas tension; and (ii) conventional (time averaged) blood-gas sample oxygen tensions. We suggest that tidal-ventilation models are needed to describe within-breath fluctuations in arterial oxygen saturation and blood-gas tension in acute respiratory distress syndrome (ARDS) subjects. Both the amplitude of these oxygen saturation and tension fluctuations, and the mean oxygen blood-gas values, are affected by physiological variables such as inspired oxygen concentration, lung volume, and the inspiratory:expiratory (I:E) ratio, as well as by changes in pulmonary shunt during the respiratory cycle. 相似文献
58.
目的在基因转录水平了解脂类代谢和运输相关基因在大鼠肝再生(LR)中的表达变化和模式。方法用搜集网站资料和查阅相关论文等方法获得参与脂类代谢和运输基因,用大鼠基因组230 2.0芯片检测它们在大鼠再生肝中的表达情况,用比较手术和假手术中基因表达的差异性确定肝再生相关基因。结果初步证实上述基因中193个基因与肝再生相关。肝再生早期[部分肝切除(PH)后0.5~4h]、前期(PH后6~12h)、中期(PH后12~66h)、后期(PH后72~168h)等4个阶段起始表达的基因数为113、20、66和1;基因的总表达次数为250、205、796和293。共上调852次,下调630次,分为27种表达方式。肝再生早期和前期胆汁酸代谢相关基因转录减弱;早期和后期糖皮质激素分解相关基因转录增强;前期和中期磷脂合成相关基因转录增强,磷脂分解相关基因转录减弱;中期脂肪酸、白三烯和鞘糖脂合成相关基因转录增强,甘油三酯和磷脂酰肌醇代谢相关基因转录增强,鞘糖脂分解相关基因转录减弱;中期和后期前列腺素合成和脂肪酸分解相关基因转录增强;几乎在整个肝再生中性激素、糖皮质激素和孕酮合成相关基因转录增强,鞘磷脂代谢相关基因转录增强,脂类运输相关基因转录增强,胆固醇代谢相关基因转录减弱。结论肝再生中脂类代谢和运输变化较大,与肝再生密切相关。 相似文献
59.
新生儿高间接胆红素血症患儿凝血象的研究及临床意义 总被引:5,自引:0,他引:5
目的 探讨凝血因子、血小板和新生儿高间接胆红素血症的关系 ;方法 用散射比浊法测定新生儿高间接胆红素血症患儿 6 0例和正常足月新生儿 2 0例的凝血酶原时间 (PT)、激活的部分凝血活酶时间 (APTT) ,同时检查血小板计数和肝功能 ;结果 新生儿高间接胆红素血症患儿的PT、APTT比正常足月新生儿组明显升高 ,有显著性差异 ,P值均 <0 .0 5 ,而血小板计数和肝功能两组间比较 ,无显著性差异 ,P值 >0 .0 5 ;结论 新生儿高间接胆红素血症患儿临床上常出现脐部渗血、穿刺部位出血不止等表现与新生儿血小板数量无关 ,而与PT、APTT延长有关 ,可能由于母乳喂养的推广和生后没有进行常规维生素K预防。因此 ,我们建议在治疗新生儿高胆红素血症的同时 ,要注意预防维生素K的缺乏。 相似文献
60.
大鼠肝抑素纯化及其生物活性的检测 总被引:3,自引:1,他引:3
用SephadecG-5凝胶过滤层析法,进一步纯化具肝抑素生物活性的大鼠肝蛋白质粗提品,以分离的大鼠再生肝的肝细胞为靶细胞,体外检测各洗脱峰浓缩物对肝细胞增殖的制率结果证明,E峰浓缩物的抑制作用最强,其活性比为粗提品的20倍,SDS聚丙烯酰胺电泳图及蛋白质迁移率测定表明,该浓缩物的主要成分为分子量13.5kD的多肽。本研究对大鼠肝抑素做了初步纯化,验证了该物质在肝再生中起重要调控作用的生物效应。 相似文献