Clove bud (Syzygium aromaticum) improved blood and hepatic antioxidant indices in laying hens receiving low n‐6 to n‐3 ratios

This study was carried out to investigate the effects of different levels of clove bud (Syzygium aromaticum) powder and vitamin E on serum lipid profile, enzyme activities and antioxidant indices, as well as hepatic biochemical and histological alterations in laying hens receiving different n‐6 to n‐3 ratios. A total of 160 laying hens, 43 weeks of age, were allotted to 8 experimental diets with 5 cages of 4 birds each. Dietary treatments consisted of two ratios of n‐6 to n‐3 (16.71 and 2.35), three levels of clove bud (0.0, 2.0 and 4.0 g/kg) and a high vitamin E level (200 mg/kg, as a positive control in each level of n‐6 to n‐3 ratio) in a 2 × 4 factorial arrangement during 70 days of the experiment. Results showed that a decline in the n‐6 to n‐3 ratio led to a reduction in serum cholesterol concentration (p < 0.05) and an increase in serum HDL content (p < 0.05). Additionally, decreasing n‐6 to n‐3 ratio and increasing clove bud level caused a remarkable decline in serum aspartate aminotransferase (p < 0.05 and p < 0.001) and alanine aminotransferase (p < 0.05 and p < 0.05) enzyme activities. Furthermore, total antioxidant capacity (p < 0.05 and p < 0.001) as well as serum vitamin E concentration (p < 0.05 and p < 0.001) was decreased and enhanced by low n‐6 to n‐3 ratio diets (LRD) and clove bud powder respectively. Decreasing the n‐6 to n‐3 ratio lowered hepatic lipid (p < 0.05) and glycogen contents (p < 0.01) as well as tissue integrity (p < 0.05), and raised liver MDA concentration (p < 0.001), markedly. Nevertheless, increments in clove bud content led to a reduction (p < 0.01) in liver relative weight (p < 0.05) and hepatic fat vacuole numbers. In general, the best synergistic responses on modulating of blood lipids and serum enzyme activities were observed when the highest level of clove bud was supplemented in the diets with low n‐6 to n‐3 ratio. Likewise, antioxidant indices were improved by administration of dietary clove bud powder although feeding fish oil was observed to elevate the susceptibility of blood and hepatocytes to lipid peroxidation.     

Sensitivity and specificity of fasting ammonia and serum bile acids in the diagnosis of portosystemic shunts in dogs and cats

Background: Portosystemic shunt (PSS) is the most common cause of hepatic encephalopathy in dogs and cats. Fasting ammonia and serum bile acids (SBA) are used to diagnose PSS, but their true sensitivity and specificity have not been fully evaluated, especially in cats. Objectives: The purpose of this study was to determine the diagnostic accuracy of fasting ammonia and SBA concentrations in the diagnosis of PSS in dogs and cats and to compare diagnostic accuracy between species. Methods: A retrospective analysis of data from 373 dogs and 85 cats presented to the clinic from 1996 to 2006 was carried out. Based on clinical, laboratory, and imaging findings, animals were grouped as having PSS, parenchymal hepatic disease, or extrahepatic disease. The sensitivity and specificity of ammonia and SBA concentrations for the diagnosis of PSS were calculated and receiver‐operating characteristic analysis was used to optimize cut‐offs. Results: Using the upper limit of laboratory reference intervals (ammonia, 59 μmol/L; SBA, 20 μmol/L), the sensitivity and specificity of ammonia was 85% and 86% in dogs, and 83% and 76% in cats, respectively. The sensitivity and specificity of SBA was 93% and 67% in dogs, and 100% and 71% in cats, respectively. Using optimal cut‐off points for ammonia (dogs, 57 μmol/L; cats, 94 μmol/L) the sensitivity and specificity was 91% and 84% in dogs and 83% and 86% in cats, respectively. Using optimal cut‐off points for SBA (dogs, 58 μmol/L; cats, 34 μmol/L) the sensitivity and specificity was 78% and 87% in dogs and 100% and 84% in cats. Conclusion: Increased fasting ammonia and SBA concentrations are accurate indicators of PSS. An improvement in diagnostic accuracy can be achieved by using defined optimal cut‐off points for the selective diagnosis of PSS.     

Signaling pathways involved in liver injury and regeneration in rabbit hemorrhagic disease, an animal model of virally-induced fulminant hepatic failure

Management of fulminant hepatic failure (FHF) continues to be one challenging problem, and experimental animal models resembling its clinical conditions are still needed. Rabbit hemorrhagic disease (RHD) fullfils many requirements of an animal model of FHF. This work investigated changes in MAPK, NF-κB, AP-1 and STAT pathways during RHD-induced liver injury. Rabbits were infected with 2 × 10⁴ hemagglutination units of an RHD virus isolate. Apoptosis was documented by the presence of caspase-3 activity and substantial PARP proteolysis at 36 and 48 h postinfection (pi). Infection induced a marked and maintained expression of TNF-α from 12 h pi, while there was only a transitory increase in IL-6 expression. Expression of phosphorylated (p)-JNK, p-p38 and p-ERK1/2 was significantly elevated at 12 h pi. At 48 h pi p-JNK expression was maintained at a maximum level, while that of p-p38 returned to normality and there was no p-ERK1/2 expression. Activation of NF-κB and AP-1 and increased expression of VCAM-1 and COX-2 were observed. No significant changes were detected in activation of STAT1 and STAT3, while SOCS3 expression increased significantly. The current findings suggest that activation of JNK is an essential component in liver injury mediated by the RHD virus and that lack of activation of STAT3, probably mediated by SOCS3 over-expression, would contribute to the inhibition of the regenerative response. Data show the presence of molecular mechanisms contributing to liver damage and the lack of regeneration and they support the usefulness of this model to investigate novel therapeutical modalities in FHF.     

四君子汤对脾虚大鼠肝脏结构与功能的影响

健康SD大鼠随机分为对照组、脾虚组、中药组（四君子汤治疗）。利血平诱导和建立大鼠脾虚模型,四君子汤进行治疗。组织学观察可见,脾虚大鼠肝细胞体积减小,核质比升高,脂肪空泡增多,肝索形态不可见;经四君子汤治疗后,肝细胞、肝索形态恢复,脂肪泡显著减少,且四君子汤有促进肝细胞增生作用。脾虚大鼠血清肝细胞损伤标志性指标ALT含量显著升高（P〈0．05）;AST显著降低（P〈0．05）,脾虚情况下肝细胞损伤、线粒体功能下降;ALP含量显著降低（P〈0．05）,肝脏合成ALP减少;GGT含量显著升高（P〈0．05）,与肝细胞膜及肝内胆管上皮损伤相关。脾虚大鼠血清CHO,IBIL与TBA含量显著升高（P〈0．05）,肝脏摄取转化和排泄胆固醇、胆红素和胆汁酸能力下降。由此可见,脾虚状态下大鼠肝脏受损,代谢胆红素及胆汁酸功能下降,脾虚黄疸为肝细胞性黄疸;四君子汤对脾虚大鼠肝脏结构改变有修复作用,一定程度回调肝功能指标,并促进肝脏代谢胆红素与胆汁酸能力恢复正常。     

NONINVASIVE ESTIMATION OF CENTRAL VENOUS PRESSURE IN ANESTHETIZED DOGS BY MEASUREMENT OF HEPATIC VENOUS BLOOD FLOW VELOCITY AND ABDOMINAL VENOUS DIAMETER

Determination of central venous pressure (CVP) is relevant to patients with right heart disease, hypovolemia, and following intravenous fluid therapy. We hypothesized that changes in CVP in dogs could be predicted by measurements of hepatic vein diameter, caudal vena cava (CVC) diameter, and hepatic venous flow velocities. Nine healthy American Foxhounds were anesthetized. Following baseline recordings, intravenous fluids were administered to increase CVP. Volume administration created treatment periods with CVP ranges of 5, 10, 15, 20, and 25 mm Hg. Flow velocities in the right medial hepatic vein were recorded using pulsed wave Doppler ultrasound. Hepatic vein, CVC, and aorta diameters were determined with B‐mode ultrasound. Variables were compared across the treatment periods by ANOVA for repeated measures. Relationships between CVP, Doppler, and B‐mode variables were evaluated using Spearman's rank correlations, multiple linear regression, and repeated measures linear regression. The a‐, S‐ and v‐wave velocities were augmented significantly with volume loading. The best part (semipartial) correlation coefficients predicting increasing CVP were identified with v‐wave velocity (0.823), S‐wave velocity (?0.800), CVC diameter (0.855), and hepatic vein diameter (0.815). Multiple linear regression indicated that CVP in this study could be predicted best by a combination of CVC and hepatic vein diameter and the v‐wave velocity (r=0.928). Ultrasound imaging identified gallbladder and pancreatic edema consistently, likely related to acute volume loading. These findings may be applicable in the assessment of volume status, dogs with right heart disease, and during serial monitoring of dogs receiving fluid or diuretic therapy.     

Identification of hepatic stem/progenitor cells in canine hepatocellular and cholangiocellular carcinoma

Hepatic progenitor cells (HPCs) are bipotential stem cells residing in human and animal livers that are able to differentiate towards the hepatocytic or cholangiocytic lineages. HPCs are present in both hepatocellular (HCC) and cholangiocellular carcinoma (CC) in humans; and a small percentage of HCC can originate from cancer stem cells. However, its distribution in canine liver tumour has not been studied. Herein, we searched for stem/progenitor cells in 13 HCC and 7 CC archived samples by immunohistochemical analysis. We found that both liver tumours presented a higher amount of K19‐positive HPCs. Besides, 61.6% of HCC cases presented immature CD44‐positive hepatocytes. Nevertheless, only two cases presented CD133‐positive cells. As observed in humans, hepatic canine tumours presented activated HPCs, with important differentiation onto hepatocytes‐like cells and minimal role of cancer stem cells on HCC. These findings reiterate the applicability of canine model in the search for new therapies before application in humans.     

乙型肝炎失代偿期肝硬化患者血清内毒素、 IL-12、IL-18水平的检测及其意义

目的探讨乙型肝炎肝硬化血清内毒素(LPS)、白介素-12(IL-12)、白介素-18(IL-18)水平变化及临床意义.方法采用鲎试剂(Ⅱ)-偶氮显色法、ELISA双抗体夹心法,分别测定80例肝硬化患者血清LPS、IL-12、IL-18水平.另设正常对照组(32例).结果与正常对照组比较,肝硬化患者血清LPS、IL-12、IL-18水平均明显升高,且随着肝功能越差,升高越明显(P＜0.01);腹水组的LPS及IL-12、IL-18水平较无腹水组也明显增高(P＜0.01).结论LPS、IL-12、IL-18均参与了乙型肝炎肝硬化的病理生理过程,并与病情的变化密切相关.检测这些指标有助于判断肝硬化患者的肝功能状况及疾病的严重程度.     

不同给药途径的姬松茸多糖对鼠急性肝损伤的保护效应及其抗氧化作用的研究

分别通过灌胃、皮下注射的方法,给予小鼠姬松茸多糖灭菌溶液,连续7d。然后经四氯化碳染毒12h后,采血并制备肝组织匀浆液进行GPT、GOT活性及SOD、MDA含量的检测。结果表明:用姬松茸多糖灌胃比皮下注射能更快、更有效的保护肝损伤;而SOD活性及MDA含量未见有统计学差异。     

乙酰甲喹在试验性肝功能损害家兔体内的药动学研究

【目的】比较乙酰甲喹在健康和肝功能损害家兔体内的药动学特征,为临床合理用药提供资料和理论依据。【方法】将12只家兔随机均分为2组,一组为健康对照组,另一组于试验前以0.4 mL/kg剂量皮下分点注射四氯化碳,以复制肝功能损害病理模型。24 h后,对2组家兔以20 mg/kg的剂量耳缘静脉快速注射乙酰甲喹20mg/kg,6 h内不同时间心脏采血8次,用高压液相色谱法测定乙酰甲喹血药浓度,用残数法逐只家兔拟合药-时曲线,以方差分析优选房室模型计算药动学参数。【结果】乙酰甲喹在家兔体内的药动学配置符合无吸收因素一室开放模型,其药-时曲线最佳方程为:C健康=25.564 2 e-0.371 6t,C肝损=24.308 9 e-0.144t。与健康组家兔相比,肝功能损害组家兔药动学参数有显著变化:半衰期t1/2延长166.49%,消除速率常数kel减小61.25%,体清除率CLB减小54.95%,药-时曲线下面积增大155.87%。【结论】家兔肝功能损害后,乙酰甲喹在其体内的消除过程显著减慢,因此在肝脏损害时应相应减小乙酰甲喹的给药剂量或增大给药间隔时间。     

中华鳖肝组织炎性细胞的浸润及其结构↑（*）

用组织化学和显微及亚显微生物技术,研究了患非寄生性肝病中华鳖（Ｔｒｉｏｎｙｘｓｉｎｅｎｓｉｓ）的外周血、肝静脉血血相变化和浸润肝组织炎性细胞的亚显微结构及其细胞免疫病理反应。结果表明,中华鳖的炎性细胞趋化性强、浸润面广。其剧烈的非特异性细胞免疫反应表现为：嗜中性粒细胞数量多、个体大、结构变化复杂,并在非特异性细胞免疫反应中发挥重要作用,其次是淋巴细胞、Ｋｕｆｅｒ细胞;肝组织中被激活的白细胞在结构和数量上发生显著变化,并在浸润肝组织后聚集、吞噬、消化,发生强烈的细胞免疫反应。红细胞发生渗出性病理反应。