Simultaneous determination of irbesartan and hydrochiorothiazide in human plasma by high performance liquid chromatography and its pharmacokinetic application

Development of a simple, rapid and routine assay for the combination lrbesartan Hydrochlorothiazide [IB/HCTZ] for the investigation of their pharmacokinetic parameters in human plasma and bioequivalence study of LB I UCT [300/12.5mg] tablets manufactured locally [Test] and originally [Reference]. After extraction of [IB.HCTZ] from plasma, it was chromatographed with mobile phase consisting of phosphate buffer: acetonitrile: methanol [65:25:10] at flow rate of 1 ml/min and detected at wavelength of 272 nm. The pharmacokinetic study was conducted in a 2 X 2 crossover design involving 24 volunteers. The criteria used to assess bioequivalence of the two products were AUC[0-t], AUC[0-infinity], C[max], and t[max]. The described method for analysis showed that the recoveries of LB I HCTZ from plasma were 99.63%and 100.793% the limit of detection were 0.015 micro g/ml and 1.5 ng/ml respectively and the regression analysis for the drug concentrations indicated excellent linearity[r>0.999] for both. Statistical analysis [ANOVA] of the measured parameters showed that there was no significant difference between the two products. The HPLC method presented is direct, simple. reproducible, sensitive and linear for the determination of lB/HCT in human plasma and is adequate for its clinical pharmacokinetic studies. besides, the Test was found to be biocquivalent to the Reference and both products can be considered interchangeable in medical practice

Enoxaparin versus unfractionated heparin in acute ischemic stroke [in-evolution type]. Differential effects of enoxaparin on von willebrand factor release and a possible relation to improved clinical outcomes

The significance of low-molecular-weight heparins [LMWHs] in the management of acute stroke remains controversial. Investigating the effect of early administration of Enoxaparin [ENOX] on risk reduction of early recurrent ischemic strokes compared with Unfractionated Heparin [UFH]. Besides, exploring whether these benefits of ENOX might lead to reduction in death and disability. One hundred patients with acute ischemic stroke in evolution were enrolled [with symptoms of stroke within eight hours randomization]. Patients were randomized to receive UFH or ENOX for ten days. National Institutes of Health Stroke Scale [NIHSS] and Computed Tomography [ct] scan were performed at the time of admission, and after 48 hours of randomization. The mean baseline of [NIHSS] were 9.14 +/- 0.62 and 7.86 +/- 0.54 among patients randomized to UFH and ENOX respectively [P-value 0.2]. At discharge, the mean NIHSS showed a statistically significant difference in favor of the ENOX group [7.9 +/- 0.82 vs 4.96 +/- 0.54 for ENOX and UFH respectively [P-value = 0.002]] The mean NIHSS after therapy in patients who demonstrated neurological improvement was 5.6 +/- 0.46 in the UFH arm compared to 3.65 +/- 0.39 in the ENOX arm [P-valne=0.001]. A deterioration in the clinical neurological condition [progressive stroke symptoms] inspite of treatment with anticoagulant therapy was seen in 20% [n=10] of the patients in the UFH treatment arm compared to none [n=0] in the ENOX treatment arm [P-value=0.005]. ENOX + aspirin was superior to UFH + aspirin in reducing adverse neurological disability after acute ischemic stroke in evolution

Bioequivalence study of 10 mg zaleplon tablets in Egyptian healthy volunteers

Development of a simple, rapid and routine assay of zaleplon [ZL] in plasma for the investigation of Zaleplon [ZL] pharmacokinetic parameters in human and to compare the bioequivalence parameters of 10 mg [ZL] tablets manufactured locally [Test] with originally [Reference]. The drug, after extraction from plasma, was chromatographic on a C-18 reversed- phase column and detected at 232 nm, the mobile phase consisted of 0.1M potassium dihydrogen phosphate: acetonitrile [35:65] V/V pH 4 adjusted with 5% orthophosphoric acid at a flow rate of 1 ml/min. The bioequivalence study was performed according to a randomized, single dose, two-treatment, two-period, two-sequence crossover study conducted on twenty-four healthy volunteers. The criteria used to assess bioequivalence of the two products were t max, C max, k ab, t ab, k 1/2el, t1/2el, AUC 0-12, and AUC 0-00. The described method for analysis showed that the recovery of ZL from plasma was 99.63% with a coefficient of variation of 0.321. Moreover, the 90% confidence intervals for the mean ratio [test/reference] of C max, AUC 0-12, and AUC 0-00 were within the acceptance range [80%-125%]. The HPLC method presented is direct, simple, reproducible, sensitive and linear for the determination of ZL in human plasma and is adequate for its clinical pharmacokinetic studies, besides, the Test was found to be bioequivalent to the Reference and both products can be considered interchangeable in medical practice

effect of green tea treatment on the glycation, antioxidant status and lipid profile in type 2 diabetic female patients

Amongst the numerous co-adjuvant therapies which could influence the incidence and progression of diabetic complications, antioxidants and flavonoids are currently being tested in several clinical trials. Green tea [GT], catechins, has been reported to possess a potent antioxidative properties, and preventive effects against various oxidative diseases. To evaluate the effect of short-term supplementation with GT and its benefit on decreasing the incidence of some of diabetic complications. The effect of GT tablets [Igm] which is equivalent to 200 mg catechin as a co-adjuvant therapy with the oral hypoglycemic drug in a group of 36 Type 2 diabetic female patients was investigated, using a randomized single-blind placebo controlled parallel design, for a period of three months. Parameters of glycation, oxidative stress, lipid profile and C-reactive protein were measured before and after the intervention. An approach to find a relationship between patients response to GT treatment and disease age [history]. GT supplementation resulted in a significantly decrease in serum fasting blood glucose, fructosamine, total-cholesterol and triglycerides by 22.40%, 8.5%, 36.53% and 42.17% respectively, in diabetic patients under this intervention, with a non significant change in HbAlc and C-reactive protein. It also increased blood GSH and serum NO level by 15.16% and 21.5% respectively with a marked decrease in serum MDA level by 43.47% in diabetic patients under this intervention. Moreover, A direct relationship was found between disease' age and patients' high response to GT administration. GT co-administration with the oral hypoglycemic drug proved to improve patients antioxidants status, lipid profile and to a little extent the glucose levels and consequently decreasing the extent and time of occurrence of diabetic complications. Recommendation of GT administration, as a natural product in diabetic female patients for a specified dosage schedule might improve patients' health and quality of life

Determination of possible interactions of citalopram hydrobromide with different excipients

Differential scanning calorimetry [DSC] and Infrared spectroscopy were used as a screening techniques for assessing the possible interactions of citalopram hydrobromide [CTH] with some currently used pharmaceutical excipients in formulation of rapidly dispersible tablets and capsules. On the basis of the DSC,NMR, UV and IR results CTH was found to be compatible with maize starch,talc, fill starch 1500,anhydrous lactose,magnesium sulphate, starch sodium glycolate,polyvinylpyrrolidoneK29/32, magnesium strearate, polyethylene glycol 4000, Avicel PH101, pharmaburst and Avicel PH101. DSC results showed some minor interactions with propylene glycol, sorbitol, Avicel PH102, soluble starch.lactose monohydrate and mannitol

In virto and in vivo effects of isoniazid on stabilityand pharmacokinetics of rifampicin

The stability of rifampicin in the presence of isoniazid was studied using several in vitro examinations including differential scanning calorimetry, infrared spectroscopy and thin layer chromatography. The results suggested the probability of the interaction between rifampicin and isoniazid. Regarding in vivo studies, the effect of isoniazid 5 mg kg-1 on the pharmacokinetics of rifampicin 10 mg kg-1 was investigated in dogs after single oral administration. Plasma rifampicin concentrations were determined using high performance liquid chromatographic assay for the determination of the drug. The effect of repeated oral administration of rifampicin-isoniazid [R-I] combination, for a period of five days in dogs, on hepatic enzymatic activity and renal function tests was studied. The present study showed a good agreement between both in vitro and in vivo results. In addition, the pharmacokinetic of rifampicin was found to be influenced by the presence of isoniazid

role of medical physics in radiation therapy

A Key Role in all medical uses of ionizing radiation is played by the radiophysicist His responsibility includes the establishment and maintenance in collaboration, with the engineering hand of accurate methods of dosimetry for both therapy and protection purposes. The other responsibility is the development of physical technique, for many uses of radioactive isotopes. His special knowledge of radiation and electronics finds many-applications in diagnostic radiology. Collaboration with the radiotherapist in the development of new techniques or in the, study of several problems