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OvB20 is an antigen of Onchocerca volvulus preferentially recognized by sera from cattle vaccinated with irradiated infective larvae of Onchocerca lienalis. Antibodies raised against the recombinant protein were used to characterize the expression of the native protein in different developmental stages of O. volvulus and the rodent filaria Acanthocheilonema viteae. In O. volvulus, antibodies reacted to a polypeptide of 42 kDa in microfilariae and with proteins of 52 and 65 kDa in third-stage larvae. No products were detected in adult stages. Immunogold electron microscopy localized the native protein to discrete patches of the hypodermis and cuticle of infective larvae. Characterization of a homologous protein in A. viteae confirmed the stage-specific expression in infective larvae of the 65-kDa protein, which was secreted during in vitro culture. Vaccination of rodents against A. viteae with a B20-maltose-binding-protein fusion protein resulted in a 49 to 60% reduction in adult worm recoveries with a corresponding 97% reduction in microfilaremia.  相似文献   
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Viral antigen was detected in the cytoplasm and in associated membranes of salivary gland acinus cells by indirect immunofluorescence and immunoperoxidase staining. Viral ribonucleoproteins (indicated histochemically by presence of pyroninophilic granules) which had accumulated in the cytoplasm of salivary gland type B (granular) acini of unfed Argas (Persicargas) arboreus Kaiser, Hoogstraal & Kohls were no longer visible 24 h after feeding. Virus in tick salivary glands increased from 300 to 500 plaque-forming units during the brief feeding interval (approximately 1 h), but virus was not detectable by 72 h. Overall salivary gland, ovarian, and synganglion tissue levels of Quaranfil virus decreased in the 96 h after feeding, except for synganglion samples in which virus titers increased during 24 h after feeding. Starvation for 105 d resulted in a sevenfold increase in salivary gland viral content compared with those starved 45 d, whereas synganglion tissue titers for Quaranfil virus became undetectable, and ovarian tissue values were similar to those starved for 45 d. Feeding had a greater effect on viral persistence in tissues for ticks starved 60 additional d (comparing 45 with 105 d) in that no Quaranfil virus was detected in any tissue after 48 h (compared with 72 h). Feeding infected ticks (with short extrinsic incubation) on chicks resulted in a peak of host mortality on days 7 and 8, whereas long extrinsic incubation resulted in sporadic mortality over 20 d of monitoring.  相似文献   
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Avanafil is a highly selective and potent oral phosphodiesterase type 5 inhibitor. However, its impact on the soluble markers of endothelial function has not been investigated yet. This study was conducted to assess the effect of daily avanafil on the endothelial markers' serum level and erectile function in patients with erectile dysfunction. In this work, we randomly divided 140 males with erectile dysfunction and other diseases commonly associated with endothelial dysfunction like diabetes mellitus, hypertension and dyslipidaemia into two equal groups: treatment group, treated with 50mg daily oral avanafil, and control group, treated with placebo. The International Index of Erectile Function-5 score and the serum levels of nitric oxide, cyclic guanosine monophosphate and endothelin-1 as markers of endothelial function were measured at baseline and after four weeks of treatment in both groups. At the end of treatment period, those randomised to avanafil achieved statistically significant improvement in erectile function, nitric oxide, cyclic guanosine monophosphate and endothelin-1 levels from baseline versus placebo regardless the type and duration of associated comorbidity as well as the duration and severity of erectile dysfunction. These results permitted us to suggest that daily avanafil can improve the impaired endothelial function associated with the erectile dysfunction.  相似文献   
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The role of hyperthermia during regional alkylating agent chemotherapy is controversial. The aim of this study was to determine the exact contribution of hyperthermia to tumor response during isolated limb infusion with l-phenylalanine mustard. Rats bearing rodent fibrosarcoma on the hindlimb underwent isolated limb infusion with saline, saline plus heat, l-phenylalanine mustard, l-phenylalanine mustard under conditions of normothermia, or l-phenylalanine mustard plus hyperthermia. Heat was administered locally using an in-line hot water circulation loop. Treatment with l-phenylalanine mustard at a concentration of 15 or 50 micrograms/mL was ineffective at producing tumor growth delay (P = 0.24 and 0.41, respectively). Furthermore, thermal enhancement of l-phenylalanine mustard activity was not seen at 15 micrograms/mL. However, administration of high-dose l-phenylalanine mustard, 50 micrograms/mL, with increasing amounts of heat yielded increasing tumor growth delay, increased regressions, and decreased proliferative index. Although l-phenylalanine mustard infusion under normothermia yielded a tumor growth delay of 7.1 days, combination l-phenylalanine mustard + hyperthermia treatment produced tumor growth delay of 27.0 days (P < 0.01; with two of five animals showing a complete response). Four hours after isolated limb infusion, 50.9% of cells in tumor treated with l-phenylalanine mustard + hyperthermia experienced apoptosis, whereas only 18.1, 16, and 4.4% of cells underwent apoptosis after treatment with l-phenylalanine mustard, saline + hyperthermia, or saline. The mean concentration of l-phenylalanine mustard within tumor relative to perfusate following isolated limb infusion was found to be similar among all groups at 0.023, 0.025, and 0.032 in animals undergoing isolated limb infusion with l-phenylalanine mustard, l-phenylalanine mustard + normothermia, and l-phenylalanine mustard + hyperthermia, respectively. These data indicate a synergistic cytotoxic effect of l-phenylalanine mustard + hyperthermia in isolated limb infusion, which is not attributable to enhanced tumor drug uptake.  相似文献   
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Background:Vitiligo is a progressive depigmenting disorder characterized by the loss of functional melanocytes from the epidermis. The etiopathogenesis of vitiligo is still unclear. Heat shock proteins (HSPs) are prime candidates to connect stress to the skin. HSPs were found to be implicated in autoimmune diseases such as rheumatoid arthritis and other skin disorders as psoriasis.Results:Our analysis revealed a significantly higher expression of HSP-70 mRNA in lesional skin biopsies from vitiligo patients compared to nonlesional skin biopsies from vitiligo patients (P < 0.001) and compared to skin biopsies from healthy controls (P < 0.001). The level of HSP-70 was not found to be correlated with age, sex, or disease duration. The expression of HSP-70 was correlated with the disease activity and patients with active vitiligo showed higher mean HSP-70 level compared to those with inactive disease.Conclusions:HSP-70 plays a role in the pathogenesis of vitiligo and may enhance the immune response in active disease.  相似文献   
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