Study of the protective effect of ascorbic acid against the toxicity of stannous chloride on oxidative damage, antioxidant enzymes and biochemical parameters in rabbits

Stannous chloride (SnCl2) is a reducing chemical agent used in several man-made products. SnCl2 can generate reactive oxygen species (ROS). Therefore, the present study has been carried out to investigate the antioxidant action of l-ascorbic acid (AA) in minimizing SnCl2 toxicity on lipid peroxidation, antioxidant enzyme, and biochemical parameters in male New Zealand white rabbits. Animals were assigned to one of four treatment groups: 0mg AA and 0mg SnCl2/kg BW (control); 40 mg AA/kg BW; 20mg SnCl2/kg BW; 20mg SnCl2 plus 40 mg AA/kg BW. Rabbits were orally administered the respective doses every other day for 12 weeks. Results obtained showed that SnCl2 significantly (P<0.05) induced thiobarbituric acid-reactive substances (TBARS; the marker of lipid peroxidation) in plasma, while the activities of glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT), and the level of sulfhydryl groups (SH-group) were decreased (P<0.05) in blood plasma. Aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (AlP), acid phosphatase (AcP) and lactate dehydrogenase (LDH) activities were decreased (P<0.05). Stannous chloride significantly (P<0.05) increased the levels of plasma total lipid (TL), cholesterol, triglyceride (TG), low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL), glucose, urea and total bilirubin. On the other hand, the level of plasma high-density lipoprotein (HDL), total protein (TP), albumin (A) and globulin (G) were significantly (P<0.05) decreased. Ascorbic acid alone significantly decreased the levels of TBARS, lipids and urea, and increased the activities of GST, SOD and CAT, and the levels of SH-group and proteins. While the rest of the tested parameters were not affected. Also, the presence of AA with SnCl2 alleviated its harmful effects on most of the tested parameters. Therefore, the present results revealed that treatment with AA could minimize the toxic effects of stannous chloride.     

Pleural tuberculosis in the United States: incidence and drug resistance

BACKGROUND: Pleural tuberculosis (TB) should be considered in any patient with a lymphocytic pleural effusion. The diagnostic approach is under debate. Knowledge of pleural TB epidemiology would be beneficial. To help clarify pleural TB epidemiology, we analyzed US national TB surveillance data for 1993 to 2003. METHODS: We compared pleural TB to pulmonary TB (where each was reported as the major site of TB disease, and no additional sites of disease were reported). Applicable statistical tests were performed; p < 0.05 was considered to be significant. RESULTS: From 1993 through 2003, 7,549 cases of pleural TB and 156,779 cases of pulmonary TB were reported (in 2003: pleural TB, 536 cases; pulmonary TB, 10,551 cases). The annual proportion of pleural TB was relatively stable (median rate, 3.6%; range, 3.3 to 4.0%) compared to that for pulmonary TB, which steadily decreased (average annual decrease, 0.9%; p < 0.01). Pleural TB occurred significantly more often than pulmonary TB among persons >/= 65 years old (30.4% vs 23.3%, respectively; p < 0.01), and it occurred significantly less often among children < 15 years old (1.8% vs 6.1%, respectively; p < 0.01) and persons 45 to 64 years old (22.9% vs 27.9%, respectively; p < 0.01). Pleural TB patients (63.4%) were born slightly more often in the United States than were pulmonary TB patients (60.9%; p < 0.01). Drug-resistance patterns of pleural TB broadly reflected those of pulmonary TB. However, isolates from pleural TB patients were less often resistant to at least isoniazid (6.0% vs 7.8%, respectively; p < 0.01) and to at least one first-line TB drug (9.9% vs 11.9%, respectively; p < 0.01) compared with pulmonary TB patients. CONCLUSIONS: Knowledge of pleural TB demographic, clinical, and drug-resistance patterns may assist clinicians in making diagnostic and therapeutic decisions.     

香辛料中多种生物毒素的污染状况调查

[目的]对黄曲霉毒素、伏马毒素和葡萄球菌肠毒素的污染情况进行调查，旨在为制定有关食品安全卫生管理规范和相关的卫生标准提供有用的资料和依据。[方法]选择桂皮、八角、胡椒、辣椒、花椒、生姜粉、大蒜等常用香辛料，进行黄曲霉毒素(AFB)、伏马毒素(Fumonisins)和葡萄球菌肠毒素(SET)污染情况的检测。[结果]香辛原料成分中霉菌污染是普遍的，香辛料的生产工艺还不能对生物毒素的污染进行消除或降低。对香辛料的辐照处理仅仅出于防止微生物生长和防腐的考虑，对生物毒素的污染消除措施有待进一步研究。     

乙肝病毒对DNA修复基因和肝癌发生的作用

目的　以HBV转基因动物模型研究乙型肝炎病毒 (HBV) ,黄曲霉毒素 (AFB1) ,DNA修复基因和肝细胞肝癌 (HCC)发生的关系。方法　对HBVx基因转基因小鼠以相同的方式和剂量给予黄曲霉毒素 (AFB1)攻击 ,比较肝癌的发生率 ;同时用逆转录———热标记扩增 (RT -HOT -PCR)的方法 ,检查HBVx基因转基因小鼠HBVx整合阳性和阴性以及AFB1攻击后 ,癌组织与癌旁组织的DNA修复基因Brca2和Nthl1的RNA表达水平。结果　 (1)黄曲霉毒素诱导 ,5 2周肝癌发生率HBVx整合阳性小鼠 2 9只 ,14只发生肝癌 (48.3% ) ;HBVx整合阴性小鼠 15只 ,3只发生肝癌 (2 0 .0 % )。两者有显著的差异 (P <0 .0 1)。(2 )HBVx整合阳性小鼠的肝组织DNA修复基因Brca2和Nthl1的RNA表达水平都低于HBVx整合阴性小鼠。经AFB1攻击形成的肝癌和癌旁组织 ,其DNA修复基因Brca2和Nthl1的RNA表达水平也低于HBVx整合阴性小鼠。结论　结果表明HBVx在宿主细胞的整合 ,影响了宿主DNA修复能力 ,从而导致宿主对致癌物质的敏感性增加 ,最终引起肝癌发生率的增加。     

基于CD161的流式检测技术在艾滋病合并结核诊断效能的评价

目的 评价基于CD161的流式检测技术在艾滋合并结核感染中的应用价值。方法 用流式检测技术分别检测58例结核病患者（TB）,55例艾滋病合并结核病患者（HIV+TB）,122例艾滋病患者(HIV)及138例健康对照（HC）全血中CD161的表达水平;同时比较CD161流式检测技术、GeneXpert、TB-DNA、γ-干扰素释放试验（IGRAs）和AFB在TB-HIV中的检测阳性率。结果 TB外周血中淋巴细胞和CD161的表达水平显著低于HC,相反TB中单核细胞和OR值高于HC,但不受HIV感染影响。当OR阈值＞0.45时,分辨HC与TB-HIV时,AUC为0.91,灵敏度92.73%,特异度84.06%。在分辨TB和HC时,AUC为0.86,灵敏度74.14% ,特异度82.61%。平行比较AFB、TB-DNA、GeneXpert、IGRAs、CD161检测方法的HIV-TB阳性率,分别为20%、40 %、54.5%、38.1%和92.7%。当HIV-TB的CD4＜100 个/μL时上述5个检测技术的阳性率分别为26%、39.1%、60.8%、30.4%和82.6%。CD4≥100 个/μL患者组检出率分别为15.6%、37.5%、50%、43.7%和100%。结论 流式CD161技术在检测活动性结核及合并艾滋病中具有很好的临床诊断应用价值。