14 research outputs found

    Papaverine-induced and endothelium-dependent relaxation in the isolated rat aortic strip.

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    In the present study, we aimed to obtain further evidence in favour of the hypothesis that nitric oxide (NO) is a major mediator of endothelium-dependent vasorelaxation and to clarify whether NO plays a role in papaverine-induced vasorelaxation. The relaxant effects of acetylcholine (Ach), acidified NaNO2 or papaverine were investigated on isolated helical strips of the rat thoracic aorta precontracted with phenylephrine in an organ bath containing Krebs solution aerated with 95% O2 and 5% CO2. The relaxation was quantified as % peak reduction of phenylephrine contracture. Saponin abolished the relaxant effects of Ach completely whereas it had no effect on the responses to acidified NaNO2 or papaverine. NG-nitro-L-arginine (L-NOARG) reduced the effects of Ach significantly, but it was ineffective on the relaxation induced by acidified NaNO2. The inhibitory action of L-NOARG was partly restored by L-arginine, but not by D-arginine. Hemoglobin, hydroxocobalamin and hydroquinone exhibited significant inhibition on the relaxation evoked by Ach and acidified NaNO2. L-NOARG, hydroxocobalamin and hydroquinone caused only limited but significant decrease in the relaxation due to papaverine. This phenomenon was also observed by increasing phenylephrine concentration leading to an enhancement in the contraction. Our findings strongly support the view that Ach-induced relaxation of rat aorta strips is mediated by free NO released from the endothelium and the results suggest that NO may indirectly contribute to papaverine-induced relaxation.</p

    Inhibitory actions of hydroxocobalamin, cyanocobalamin, and folic acid on the ultraviolet light-induced relaxation of the frog upper oesophageal strip.

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    The applications of ultraviolet (UV) light (336 nm) on the upper oesophageal strips of frog elicited relaxant responses in the presence of NaNO2 (50 microM). The tissues were mounted under the tension 0.5 g in an organ bath containing Ringer solution, maintained at 25 degrees C and gassed with 100% O2. The responses were recorded on a kymograph via an isotonic lever. Antimegaloblastic agents, including hydroxocobalamin (1, 10, and 100 microM), cyanocobalamin (1, 10, 25, and 100 microM), and folic acid (1, 10, 50, 100, and 200 microM), significantly attenuated the relaxation response to UV light. Folinic acid (1, 10, 25, and 100 microM), however, enhanced the relaxation. Pyrogallol (50 microM), hydroquinone (50 microM), and diethyldithiocarbamic acid (8 mM) were found ineffective for attenuation, though FeSO4 (200, 400, and 500 microM) and hemoglobin (50 microM), respectively, exerted significant inhibition. L-arginine methylester (500 microM) did not impair UV-induced relaxation. Based on these results, we concluded that a mechanism involving undefined action(s) of antimegaloblastic drugs may cause alterations in the UV light-induced relaxation of the tissue used.</p

    Inhibitory actions of hydroxocobalamin, cyanocobalamin, and folic acid on the ultraviolet light-induced relaxation of the frog upper oesophageal strip.

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    The applications of ultraviolet (UV) light (336 nm) on the upper oesophageal strips of frog elicited relaxant responses in the presence of NaNO2 (50 microM). The tissues were mounted under the tension 0.5 g in an organ bath containing Ringer solution, maintained at 25 degrees C and gassed with 100% O2. The responses were recorded on a kymograph via an isotonic lever. Antimegaloblastic agents, including hydroxocobalamin (1, 10, and 100 microM), cyanocobalamin (1, 10, 25, and 100 microM), and folic acid (1, 10, 50, 100, and 200 microM), significantly attenuated the relaxation response to UV light. Folinic acid (1, 10, 25, and 100 microM), however, enhanced the relaxation. Pyrogallol (50 microM), hydroquinone (50 microM), and diethyldithiocarbamic acid (8 mM) were found ineffective for attenuation, though FeSO4 (200, 400, and 500 microM) and hemoglobin (50 microM), respectively, exerted significant inhibition. L-arginine methylester (500 microM) did not impair UV-induced relaxation. Based on these results, we concluded that a mechanism involving undefined action(s) of antimegaloblastic drugs may cause alterations in the UV light-induced relaxation of the tissue used.</p

    Vanishing bile duct and Stevens-Johnson syndrome associated with ciprofloxacin treated with tacrolimus

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    Stevens-Johnson syndrome (SJS) is a serious and potentially life-threatening disease. Vanishing bile duct syndrome (VBDS) is a rare cause of progressive cholestasis. Both syndromes are mostly related with drugs. We report a case of a patient with ciprofloxacin-induced SJS and acute onset of VBDS, and reviewed the related literature. It is the first case of ciprofloxacin-induced VBDS successfully treated with tacrolimus. This case reminds physicians of the importance of drug reactions, their severity, techniques for diagnosis and methods of management

    Biochemical and histopathologic assessment of effects of acitretin on epiphyseal growth plate in rats

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    WOS:000551559000009PubMed: 32792874Introduction: Acitretin is a commonly used retinoid in dermatology. Although there are generally known side effects, the effects on the epiphyseal plaque and bone metabolism are not clear in the literature. Aim: To histopathologically investigate the effects on the epiphyseal plate and assess variations in bone metabolism caused by acitretin. Material and methods: Three groups were formed with 10 rats in each group. The 1st group (n = 10, 5 male, 5 female) were administered 10 mg/kg/day oral acitretin solution and the 2nd group (n = 10, 5 male, 5 female) were administered 3 mg/kg/day oral acitretin solution. The control group were given normal standard feed and water. Rats were sacrificed at the end of 4 weeks. The proximal tibias were excised and histopathologically and immunohistochemically assessed. Biochemical assessment was also carried out. Results: Staining with haematoxylin-eosin found reductions in the epiphyseal plate in the 1st and 2nd group compared to the control group, though this situation was not statistically significant. Immunohistochemical studies did not encounter Type II collagen in the epiphyseal bone, proliferative zone and hypertrophic zone in the control group, low dose acitretin solution group and high dose acitretin solution group. Type II collagen was not observed in osteoids and osteoblasts. Type I collagen was not observed in the hypertrophic zone and proliferative zone of any group. Conclusions: Our data show that though acitretin caused degeneration of the epiphyseal plate, it did not cause clear thinning and we identified no significant variations in bone metabolism markers.Yuzuncu Yil University Scientific Research Project ChairWe thank the Yuzuncu Yil University Scientific Research Project Chair for funding this research.; This study was conducted in the Department of Dermatology of the Yuzuncu Yil University

    Health Related Quality of Life in children with Autism Spectrum Disorders: The clinical and demographic related factors in Turkey

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    WOS: 000318194700002We aimed to investigate the Health Related Quality of Life and related clinical variables (HRQoL) of children with Autism Spectrum Disorders (ASD). We included 102 children with ASD (46 with autism, 38 with pervasive developmental disorder not otherwise specified (PDD-NOS) and 18 with Asperger's syndrome (AS)) and 39 typically developing children as a control (TDC), between 3 and 18 years of age. The mothers scored the Pediatric Quality of Life Inventory 4.0 (PedsQLTM 4.0). The physical health, psychosocial health and total summary score of ASD group were significantly lower than TDC. Within ASD group, psychosocial (p < 0.001), social, school functioning and total summary score (p < 0.001) of the autism group were lower than AS, and PDD-NOS. The scores of AS and PDD-NOS were similar. PedsQL scores differed between the groups who take psychotropic medication and continue to special and formal education in ASD. PedsQL scores were negatively correlated with the Childhood Autism Rating Scale (CARS) score and positively correlated with the age that first signs appeared (p < 0.01). Within ASD group the children with autism had the poorer HRQoL than AS and PDD-NOS. The correlation between HRQoL and CARS scores was moderate. The severity of ASD has negative effects on HRQoL. (C) 2012 Elsevier Ltd. All rights reserved
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