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71.
We have examined the effect of addition of hydroxocobalamin to growth medium on the activity of the adenosylcobalamin-requiring enzyme methylmalonyl CoA mutase in normal human fibroblasts and in mutant human fibroblasts derived from patients with inherited methylmalonicacidemia. The mutant cell lines were assigned to four distinct genetic complementation groups (cbl A, cbl B, cbl C, and cbl D), each deficient in some step in the synthesis of adenosylcobalamin from hydroxocobalamin. After control cells were grown in cobalamin-supplemented medium, mutase holoenzyme activity increased markedly in a time- and concentration-dependent fashion. Growth in cobalamin-supplemented medium had no effect on mutase activity in some mutant lines belonging to the cbl B group, while activity increased severalfold in other cbl B mutants and in all cbl A, cbl C, and cbl D mutants examined, although mutase activity was still <10% of control. Comparison of mutase holoenzyme activity and total propionate pathway activity suggests that enhancement of mutase activity in mutant cells after cobalamin supplementation to values 5–10% of control may be sufficient to overcome the inherited metabolic block and to restore total pathway activity to normal.This work was supported in part by a research grant from the National Institutes of Health (AM 12579). H. F. W. is a recipient of a traineeship from the National Institutes of Health (T01-GM02299).  相似文献   
72.
Forty-eight intact and eight splenectomized cattle were used to evaluate different systems of coinfectious immunization against Babesia bigemina, Babesia argentina, and Anaplasma marginale. Coinfectious immunity was induced by two methods: (1) blood of cattle acutely infected with B. bigemina, B. argentina and A. marginale was used as the source of inoculum and the post vaccination reactions were chemotherapeutically controlled with Imidocarb, Ganaseg, Gloxazone, and Liquamycin, and (2) by artificially inducing babesiosis with the blood of carrier cattle with chronic infections of B. bigemina and B. argentina without chemotherapy. The degree of resistance was determined by bloodborne and tick-borne challenges. Ticks were collected from cattle and identified as Boophilus microplus and Dermacentor nitens. Vaccinated cattle demonstrated a high degree of resistance to babesiosis and anaplasmosis; however, cattle without coinfectious immunity were treated chemotherapeutically to prevent death losses.  相似文献   
73.
BACKGROUNDS: Recently, potential liver toxicity was discussed with the intake of kava extract preparations (Piper methysticum) as anxiolytic drugs. The aim of this study was to test chronic toxicity in rats by oral application of an ethanolic kava full extract. METHODS: Wistar rats of both sexes were fed 7.3 or 73 mg/kg body weight of ethanolic kava extract for 3 and 6 months. The animals were examined for changes in body weight, hematological and liver parameters, and macroscopical and microscopical histological changes in the major organs. RESULTS: No signs of toxicity could be found. CONCLUSIONS: The results are in accordance with the medical experience regarding the use of kava preparations and the long tradition of kava drinking in the South Pacific island states. Specifically, the results do not back the suspicion of potential liver toxicity.  相似文献   
74.
Malathion (MAL) is an organophosphate insecticide that disrupts the body's antioxidant system; it is one of the earliest organophosphate insecticides extensively used as dust, emulsion, and vapor control a wide variety of insect pests under different conditions. This experimentation aims to evaluate the influence of Arabica coffee oil and olive oil on MAL-induced nephrotoxicity in male rat. 6 sets bearing the same number of animals were applied to this experiment. Each set comprised 10 rats. The first set of rats was used as the control group; rats in the second set were exposed to MAL measured at 100 mg/kg body weight for 7 weeks. Animals in the third and fourth set were treated with 400 mg/kg body weight of Arabica coffee oil and olive oil, and 100 mg/kg body weight of MAL. The fifth, together with the sixth set, were fed with a similar proportion of Arabica coffee oil and olive oil as administered to the third set of rats. After the experimental duration, rats of group 2 showed severe biochemical alterations, including significant increases of creatinine, uric acids, and urea nitrogen (BUN), resulting in marked decreases in serum albumin values and total protein (TP). Severe histopathological and immunohistochemical alterations of kidney tissues were observed in exposed MAL-intoxicated rats. Administration of these oils reduced the detected biochemical, histopathological modifications caused by MAL intoxication. Two active ingredients in Arabica coffee oil (oleic acid) and olive oil (hydroxytyrosol) showed good cyclooxygenase-2 (COX 2) interaction. Moreover, oleic acid from coffee oil and olive oil exhibited impressive association with xanthine oxidase (XO). The current finding showed that coffee oil and olive oil could be appraised as possible and a likely deterrence component against nephrotoxicity brought about by MAL.  相似文献   
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快速、准确鉴定出病原体是临床感染性疾病诊断和传染病预防控制的基础。高通量测序基因检测技术突破了传统检测手段的时效性、灵敏度等的局限,为病原体检测和研究提供了便捷、高效的途径。本综述以高通量测序技术发展过程为基础,回顾纳米孔三代测序技术,及其在病毒性传染病检测鉴定及研究中的应用,并对该技术的应用前景及可能存在的问题进行阐述,期望它能在病毒性传染病的防控方面发挥更大的作用。  相似文献   
78.
The optimisation of two series of 4-hydroxybenzothiazolone derived β2-adrenoceptor agonists, bearing α-substituted cyclopentyl and β-phenethyl amino-substituents, as inhaled long-acting bronchodilators is described. Analogues were selected for synthesis using a lipophilicity based hypothesis to achieve the targeted rapid onset of action in combination with a long duration of action. The profiling of the two series led to identification of the α-substituted cyclopentyl analogue 2 as the optimal compound with a comparable profile to the inhaled once-daily long-acting β2-adrenoceptor agonist indacaterol. On the basis of these data 2 was promoted as the backup development candidate to indacaterol from the Novartis LABA project.  相似文献   
79.
Experimental data suggest that the B-cell antigen CD20 may play a significant role in the pathogenesis of many diseases including glomerular diseases. These and other findings underpin the central concept of B-cell-depleting therapies that target CD20 antigen as treatments for lupus nephritis, idiopathic membranous nephropathy, focal segmental glomerulosclerosis, cryglobulinemic glomerulonephritis, antibody mediated renal allograft rejection and recurrent glomerulonephritis in renal allograft. Use of rituximab as a B-cell depleting therapy has been associated with clinical improvement and has emerged as a possible adjunct or alternative treatment option in this field of nephrology.  相似文献   
80.
Neglected tropical diseases are defined operationally as diseases that prevail in “tropical” regions and are under‐researched, under‐funded, and under‐treated compared with their disease burden. By analysing the adjectives “tropical” and “neglected,” I expose and interrogate the discourses within which the term “neglected tropical disease” derives its meaning. First, I argue that the term “tropical” conjures the notion of “tropicality,” a form of Othering which erroneously explains the disease‐prevalence of “tropical” regions by reference to environmental determinism, rather than colonialism and neocolonialism. Second, I examine the way in which this Othering enables the abjection of tropical regions and their peoples, leading to neglect. I recommend that the term “neglected tropical diseases” be more carefully contextualised within health scholarship, education, and policy.  相似文献   
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