RESUMEN
With the development of nanomaterials in electrochemical sensors, the use of nanostructures to modify the electrode surface has been shown to improve the kinetics of the electron transfer process. In this study, a sensor was developed for the electrochemical determination of Acyclovir (ACV) based on the modified carbon paste electrode (CPE) by CdO/Fe3O4. The magnetic CdO nanoparticles characterization was studied by energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). To study of the modified CPE surface morphology, scanning electron microscopy (SEM) was used. At the optimal conditions, a noteworthy enhancement in the electrochemical behavior of ACV was observed at the surface of the modified CPE compared to the unmodified CPE. A detection limit of 300 nM and a linear range of 1-100 µM were obtained for the quantitative monitoring of ACV at the modified CPE surface using differential pulse voltammetry (DPV) in phosphate buffer. The RSD% (relative standard deviation) of the electrode response was <4.3% indicating the development of a high precision method. Also, satisfactory results were obtained in the determination of ACV with the modified electrode in tablet, blood serum, and urine samples with a satisfactory relative recovery (RR%) in the range of 94.0-104.4%.
RESUMEN
Occlusion of the artery of organs results in ischaemia. The opening of occluded artery results in tissue lesion identified as reperfusion injury (RI). Renin-angiotensin system seems to be involved in the RI. In this study we assessed the effects of different doses of two inhibitors of angiotensin converting enzyme (captopril or enalapril) and an angiotensin receptor type 1 (AT1) receptor blocker (losartan) in the RI of the kidney of rats. Female rats of 200-250 g were anaesthetized and used for RI studies. Different doses of captopril (5, 20 and 80 mg/kg), enalapril (1, 4 and 16 mg/kg) and/or losartan (5, 10 and 20 mg/kg) were used (s.c.) 120 min prior to the initiation of RI. Kidneys were removed and checked histologically for the presence and the grading of ischaemic injury. Appropriate controls were used as well, RI produced lesions comparable with that of ischaemia. Different doses of captopril or enalapril prevented these lesions. This is suggestive of the involvement of renin-angiotensin system in the RI. Different doses of losartan failed to prevent RI lesions which suggest that the effect of captopril or enalapril are not mediated through the AT1 receptors. Further studies on the involvement of AT2 receptor or other independent mechanisms are suggested.
Asunto(s)
Captopril/uso terapéutico , Enalapril/uso terapéutico , Riñón/efectos de los fármacos , Receptor de Angiotensina Tipo 1/fisiología , Daño por Reperfusión/prevención & control , Bloqueadores del Receptor Tipo 1 de Angiotensina II , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Animales , Captopril/farmacología , Relación Dosis-Respuesta a Droga , Enalapril/farmacología , Riñón/patología , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/patologíaRESUMEN
BACKGROUND: Finding new tolerable methods in weight loss has largely been an issue of interest for specialists. Present study compared a novel method of calorie shifting diet (CSD) with classic calorie restriction (CR) on weight loss in overweight and obese subjects. METHODS: Seventy-four subjects (body mass index ≥25; 37) were randomized to 4 weeks control diet, 6 weeks CSD or CR diets, and 4 weeks follow-up period. CSD consisted of three phases each lasts for 2 weeks, 11 days calorie restriction which included four meals every day, and 4 h fasting between meals follow with 3 days self-selecting diet. CR subjects receive determined low calorie diet. Anthropometric and metabolic measures were assessed at different time points in the study. RESULTS: Four weeks after treatment, significant weight, and fat loss started (6.02 and 5.15 kg) and continued for 1 month of follow-up (5.24 and 4.3 kg), which was correlated to the restricted energy intake (P < 0.05). During three CSD phases, resting metabolic rate tended to remain unchanged. The decrease in plasma glucose, total cholesterol, and triacylglycerol were greater among subjects on the CSD diet (P < 0.05). Feeling of hunger decreased and satisfaction increased among those on the CSD diet after 4 weeks (P < 0.05). CONCLUSIONS: The CSD diet was associated with a greater improvement in some anthropometric measures, Adherence was better among CSD subjects. Longer and larger studies are required to determine the long-term safety and efficacy of CSD diet.
RESUMEN
Four pre-medication drugs are used to relieve pain, allay anxiety, reduce secretion and enhance hypnosis, were evaluated for their effects on ischemia reperfusion (I/R) injury which is one of the major complications of vascular and transplantation surgery. Right kidney was removed from female rats (210-250 g) 3 weeks before surgical procedure. Different doses of morphine (0.5, 2 and 5 mg/kg), promethazine (1, 2 and 5 mg/kg), atropine (0.1, 0.3 and 0.5 mg/kg) and alprazolam (0.08, 0.32 and 0.64 mg/kg) were administered subcutaneously 30 min before left renal artery occlusion and 6 h reperfusion. Left kidneys were processed for histological evaluations. Creatinine and BUN were measured in serum samples. Morphine, promethazine, atropine and alprazolam at all evaluated doses significantly decreased serum creatinine and BUN levels and histopathological scores. The effects of promethazine (1 mg/kg) and all doses of alprazolam were more potent than other pre-medication drugs and doses. This study suggested a protective effect of these pre-medication drugs on I/R injury. Although obvious studies are required, these findings may lead to effective therapies against I/R injury.