Voltammetric determination of melatonin in tablet dosage forms and human serum

The electrochemical oxidation of melatonin is studied in Britton-Robinson buffer in the pH range 2.2-11.8 by cyclic voltammetry at glassy carbon electrode. Three irreversible, diffusion-controlled oxidation peaks were obtained. The utility of using differential pulse and square wave techniques for determination of melatonin was examined. Different parameters affecting the peak current were analylzed and at optimum conditions, linear calibration plots from 0.02-0.5 mM and 0.04 to 0.5 mM of melatonin were obtained applying the two techniques, respectively. The differential pulse mode was successfully applied to the determination of melatonin in commercial tablets containing about three-folds of vitamin B6 without previous separation. The same technique was also used for melatonin determination in human serum with acceptable accuracy.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Voltammetric determination of melatonin in tablet dosage forms and human serum

The electrochemical oxidation of melatonin is studied in Britton-Robinson buffer in the pH range 2.2-11.8 by cyclic voltammetry at glassy carbon electrode. Three irreversible, diffusion-controlled oxidation peaks were obtained. The utility of using differential pulse and square wave techniques for determination of melatonin was examined. Different parameters affecting the peak current were analylzed and at optimum conditions, linear calibration plots from 0.02-0.5 mM and 0.04 to 0.5 mM of melatonin were obtained applying the two techniques, respectively. The differential pulse mode was successfully applied to the determination of melatonin in commercial tablets containing about three-folds of vitamin B6 without previous separation. The same technique was also used for melatonin determination in human serum with acceptable accuracy.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Relaxation of ultrasonic waves in ternary TeO2-V2O5-Sm2O3 glasses

Studies were carried out on the attenuation of longitudinal ultrasonic waves in tellurite glasses containing vanadium and samarium oxides with different concentrations, using the pulse echo technique. Glass samples were prepared in the form (composition in mol%): 65 TeO2 - (35 - x) V2O5 - x Sm2O3, where x = 0.1, 0.5, 1.0, 2.0, 3.0, 4.0 and 5.0 mol%. The temperature dependence of the attenuation at ultrasonic frequencies of 2, 4, 6, and 10 MHz in the temperature range 150 to 280 Κ was proved. The shape of the loss peaks, i.e. the relaxation spectra, showed the presence of well-defined peaks at various temperatures depending upon glass composition and operating frequency. It was observed that these loss peaks shift to higher temperatures with increasing frequency suggesting some kind of relaxation process. Activation energies of the relaxation process, and deformation potential were calculated. Results showed that activation energies are strongly dependent on the samarium oxide content. Deformation potential is also frequency- and composition-dependent. Discussion of the results obtained in this study is reported

Coccydynia - a medical condition with multiple causes and different management strategies: A local experience

Background: Coccydynia is a common complaint which is usually self-limited and tolerable. Although most of these patients respond dramatically to conservative measures, some patients need more complex plane of treatment. In these conditions, the cause of coccydynia can be complex and multifactorial. Patients and methods: A total of 8 cases were included in the study. All cases received medical treatment for 9 months before surgery. Complete coccygectomy was performed for all cases. Post-operative outcomes were measured according to the degree of pain relief. Results: The mean age of the included cases was 43.87 years (range, 39 – 52). A total of 5 females (62.5%) and 3 males (37.5%) were included. The mean preoperative VAS score was 9 (range, 8 – 10), while post-operatively, it decreased significantly down to 2 (range, 1 – 3). Excellent postoperative outcomes were achieved in 6 cases (75%) whereas good outcomes were obtained in the remaining 2 cases (25%). Conclusion: Although conservative medical measures are effective for treating coccydynia, but surgical excision is still a valid treatment option in resistant cases

The protective effects of cerium oxide nanoparticles against hepatic oxidative damage induced by monocrotaline

Kamal A Amin1, Mohamed S Hassan2, El-Said T Awad3, Khalid S Hashem11Department of Biochemistry, 2Department of Internal Medicine, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef, Egypt; 3Department of Biochemistry, Faculty of Veterinary Medicine, Cairo University, Cairo, EgyptObjective: The objective of the present study was to determine the ability of cerium oxide (CeO2) nanoparticles to protect against monocrotaline (MCT)-induced hepatotoxicity in a rat model.Method: Twenty male Sprague Dawley rats were arbitrarily assigned to four groups: control (received saline), CeO2 (given 0.0001 nmol/kg intraperitoneally [IP]), MCT (given 10 mg/kg body weight IP as a single dose), and MCT + CeO2 (received CeO2 both before and after MCT). Electron microscopic imaging of the rat livers was carried out, and hepatic total glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPX), glutathione S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT) enzymatic activities were quantified.Results: Results showed a significant MCT-induced decrease in total hepatic GSH, GPX, GR, and GST normalized to control values with concurrent CeO2 administration. In addition, MCT produced significant increases in hepatic CAT and SOD activities, which also ameliorated with CeO2.Conclusions: These results indicate that CeO2 acts as a putative novel and effective hepatoprotective agent against MCT-induced hepatotoxicity.Keywords: monocrotaline, ceruim oxide nanoparticle, hepatotoxicity, oxidative stres

Sensitive spectrophotometric methods for determination of some organophosphorus pesticides in vegetable samples

Three rapid, simple, reproducible and sensitive spectrophotometric methods (A, B and C) are described for the determination of two organophosphorus pesticides, (malathion and dimethoate) in formulations and vegetable samples. The methods A and B involve the addition of an excess of Ce4+ into sulphuric acid medium and the determination of the unreacted oxidant by decreasing the red color of chromotrope 2R (C2R) at a suitable lmax = 528 nm for method A, or a decrease in the orange pink color of rhodamine 6G (Rh6G) at a suitable lmax = = 525 nm. The method C is based on the oxidation of malathion or dimethoate with the slight excess of N-bromosuccinimide (NBS) and the determination of unreacted oxidant by reacting it with amaranth dye (AM) in hydrochloric acid medium at a suitable lmax = 520 nm. A regression analysis of Beer-Lambert plots showed a good correlation in the concentration range of 0.1-4.2 μg mL−1. The apparent molar absorptivity, Sandell sensitivity, the detection and quantification limits were calculated. For more accurate analysis, Ringbom optimum concentration ranges are 0.25-4.0 μg mL−1. The developed methods were successfully applied to the determination of malathion, and dimethoate in their formulations and environmental vegetable samples

Cytotoxic Activity and Metabolic Profiling of Fifteen Euphorbia Species

Euphorbia is a large genus of flowering plants with a great diversity in metabolic pattern. Testing the cytotoxic potential of fifteen Euphorbia species revealed highest activity of E. officinarum L. against CACO2 cell line (IC50 7.2 µM) and of E. lactea Haw. against HepG2 and MCF-7 cell lines (IC50 5.2 and 5.1 µM, respectively). Additionally, metabolic profiling of the fifteen tested species, using LC-HRMS, for dereplication purposes, led to the annotation of 44 natural compounds. Among the annotated compounds, diterpenoids represent the major class. Dereplication approach and multivariate data analysis are adopted in order to annotate the compounds responsible for the detected cytotoxic activity. Results of PCA come in a great accordance with results of biological testing, which emphasized the cytotoxic properties of E. lactea Haw. A similarity correlation network showed that the two compounds with the molecular formula C16H18O8 and C20H30O10, are responsible for cytotoxic activity against MCF-7 and HepG2 cell lines. Similarly, the compound with molecular formula C18H35NO correlates with cytotoxic activity against CACO2

UTILITY OF CERTAIN σ AND π-ACCEPTORS FOR THE SPECTROPHOTOMETRIC DETERMINATION OF VORICONAZOL ANTIFUGAL DRUG IN PHARMACEUTICAL FORMULATION

Objective: Studies were carried out, for the first time, to investigate the charge-transfer reactions of voriconazole antifungal drug (VOR) as n-electron donor with the σ-acceptor iodine (I2) and various Ï€-acceptors: 7,7,8,8-tetracyanoquinodimethane (TCNQ); 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and p-chloranilic acid (p-CLA).Methods: The formation of the colored charge-transfer complexes were utilized in the development of simple, rapid and accurate spectrophotometric methods for the analysis of voriconazole in pure form as well as in its pharmaceutical formulation (tablets). Different variables affecting the reactions were studied and optimized.Results: Under the optimum reaction conditions, linear relationships with good correlation coefficients (0.9994–0.9999) were found between the absorbance and the concentration of voriconazole in the range of 2.0–120 μg mL−1. For more accurate analysis, Ringbom optimum concentration range was found to be between 4.0-110 μg mL-1. The limits of detection ranged from 0.36 to 1.23 μg mL−1andthe limits of quantification ranged from 1.20 to 4.10 μg mL−1. A Job's plot of the absorbance versus the molar ratio of voriconazole to each of acceptors under consideration indicated (1:1) ratio.Conclusion: The proposed methods were applied successfully for simultaneous determination of voriconazole in tablets with good accuracy and precision and without interferences from common additives. The results were compared favourably with the reported method.Â

Arabic gum acacia improves diabetic peripheral neuropathy in rats: a biochemical and histopathological evidence

Background: Diabetic peripheral neuropathy (DPN) is a frequent complication of diabetes mellitus and unfortunately, its present therapeutic alternatives are exceptionally poor. Objectives of this study was to assess the antidiabetic, antioxidant and hypolipidemic action of Gum Arabic (GA) and its role in promoting the functional recovery from diabetic neuropathy developed in in an experimental model of diabetic neuropathy.Methods: Sixty adult male Sprague-Dawley rats were utilized and randomly assigned into six groups (n= 10); control, Arabic gum-treated, untreated diabetic, diabetic received metformin, diabetic received metformin and B12 vitamin and diabetic received metformin, B12 vitamin and AG. Locomotor activity and hyperalgesia were assed at the end of the study. Fasting and two hours post-prandial blood glucose, serum insulin levels, lipid Profile, oxidants/antioxidants parameters were assessed in the blood. Sciatic nerve was assessed histopathologically.Results: The locomotor activity of the untreated diabetic rats was significantly (p<0.001) reduced compared to the control group while it was significantly increased in all treated groups. The lipid profile and Malondialdehyde were significantly improved in all treated groups. Levels of CAT, GSH, SOD, GPx were significantly decreased in untreated diabetic group compared to the control while they were significantly increased in all treated groups compared to the untreated diabetic group. Sciatic nerve fibers of untreated diabetic rats showed degenerated axons with dilated myelin sheaths and degenerated Schwann cells. The nerve had significantly fewer fiber compared to the control. These changes were alleviated in all the treated groups specifically that received metformin, vitamin B12 and GA.Conclusions: It could be concluded that Arabic gum had hypoglycemic, antioxidant and hypolipidemic activity and had a protective effect on diabetic neuropathy. Based on this it is recommended that human clinical trials are necessary to prove this therapeutic effect