Diabetes mellitus is a major health problem that threatens the whole world. According to WHO reports, the prevalence of diabetic patients in egyptis expected to increase from 2,623,000 in 2000 to be 6,726,000 in 2030. Metformin is the first line drug for type 2 diabetes mellitus, which can be used alone or in combination with other drugs. However, the concomitant use of metformin with stevia needs more investigation to clarify the role of this combination as a new strategy in type 2 diabetes mellitus. Type 2 diabetes mellitus was induced in rats by i.p. injection of STZ and NA. Animals were divided into five groups, each contains 8 rats. Group I: negative control, group II: diabetic control received saline, group III: diabetic rats received 400 mg/kg/day stevia aqueous extract, group IV: diabetic rats received metformin 250 mg/kg/day, group V: diabetic rats received stevia 400 mg/kg/day + metformin 250 mg/kg/day. After 3 weeks blood samples were collected, animals were sacrificed and tissue samples were collected. Biochemical parameters including FBG, serum insulin, serum DPP-4, TC, TG, LDL, HDL, GSH and MDA were measured by colorimetric and ELISA methods. Both stevia and metformin significantly reduced FBG level. While serum insulin significantly increased. Serum DPP-4 was significantly reduced in all treated groups, concerning lipid profile, stevia and metformin significantly lowered TC, TG, LDLand increased HDL. Both stevia and metformin significantly decreased MDA and increased GSH compared to diabetic rats. In addition, stevia significantly improved the antidiabetic effects of metformin. Stevia has an antihyperglycemic effect and could increase the antidiabetic activity of metformin. DPP-4 attenuation, antioxidant and insulin-sensitizing effects may be involved in the antidiabetic action of stevia. Regarding lipid profile stevia showed hypolipidemic effect.

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Hydrophilic matrices, especially HPMC based, are widely used to provide sustained delivery where drug release occurs mainly by diffusion. A 32 full factorial design was used to develop and evaluate HPMC matrix tablet for sustained delivery of diclofenac. The influences of polymer concentration/viscosity, diluent type/ratio, drug load/solubility, compression force and pH change on drug release were investigated. Ten tablet formulations were prepared using wet granulation. HPMC K15M (10-30% w/w) was used as the polymer forming matrix. The release kinetics, compatibility studies, lot reproducibility and effect on storage were discussed. Increasing polymer concentration and compression force showed antagonistic effect on release rate. Mannitol tends to increase release rate more than lactose. Reversing diluent ratio between lactose and MCC did not affect drug release. Changing pH resulted in burst release whereas drug solubility is pH independent. F1 showed similar release to VoltarenÆ SR and followed Higuchi model. Drug and polymer were compatible to each other. The formulation is stable at long and intermediate conditions with a significant increase in release rate at accelerated conditions due to water uptake and polymer swelling. The developed formulation was successful for a sustained delivery of diclofenac.

Hydrophilic matrices, especially HPMC based, are widely used to provide sustained delivery where drug release occurs mainly by diffusion. A 32 full factorial design was used to develop and evaluate HPMC matrix tablet for sustained delivery of diclofenac. The influences of polymer concentration/viscosity, diluent type/ratio, drug load/solubility, compression force and pH change on drug release were investigated. Ten tablet formulations were prepared using wet granulation. HPMC K15M (10-30% w/w) was used as the polymer forming matrix. The release kinetics, compatibility studies, lot reproducibility and effect on storage were discussed. Increasing polymer concentration and compression force showed antagonistic effect on release rate. Mannitol tends to increase release rate more than lactose. Reversing diluent ratio between lactose and MCC did not affect drug release. Changing pH resulted in burst release whereas drug solubility is pH independent. F1 showed similar release to VoltarenÆ SR and followed Higuchi model. Drug and polymer were compatible to each other. The formulation is stable at long and intermediate conditions with a significant increase in release rate at accelerated conditions due to water uptake and polymer swelling. The developed formulation was successful for a sustained delivery of diclofenac.

Two different fabrication methods were performed and compared for preparation of binary metallic oxide microstructures supported on a reduced graphene oxide (rGO) modified graphite electrode. Nickel–Cobalt oxide microspheres (NiCo2O4 MSs) were prepared by two different deposition methods: wet chemical and in situ-electrical deposited methods. Different characterization methods were conducted, including cyclic voltammetry (CV), scanning emission microscopy (SEM), electrochemical impedance spectroscopy (EIS) and Raman spectroscopy. The deposition methods of NiCo2O4 MSs were found to affect the electrochemical behavior of the modified electrodes towards the oxidation of venlafaxine (VEN), an antidepressant drug. The fabricated electrode showed linearity over the range 5–500 nmol L_1 and an excellent sensitivity with a limit of detection (LOD) and limit of quantitation (LOQ) of 3.4 and 10.3 nmol L_1, respectively. It was revealed that the wet-NiCo2O4@rGO modified electrode prepared by the wet chemical method showed an improved electrochemical behavior for determination of VEN in pharmaceuticals and human plasma with high recovery results in the range of 96.7–98.6% and 96.0–100.7%, respectively without any interference from the co-existing components.

Two different fabrication methods were performed and compared for preparation of binary metallic oxide microstructures supported on a reduced graphene oxide (rGO) modified graphite electrode. Nickel–Cobalt oxide microspheres (NiCo2O4 MSs) were prepared by two different deposition methods: wet chemical and in situ-electrical deposited methods. Different characterization methods were conducted, including cyclic voltammetry (CV), scanning emission microscopy (SEM), electrochemical impedance spectroscopy (EIS) and Raman spectroscopy. The deposition methods of NiCo2O4 MSs were found to affect the electrochemical behavior of the modified electrodes towards the oxidation of venlafaxine (VEN), an antidepressant drug. The fabricated electrode showed linearity over the range 5–500 nmol L_1 and an excellent sensitivity with a limit of detection (LOD) and limit of quantitation (LOQ) of 3.4 and 10.3 nmol L_1, respectively. It was revealed that the wet-NiCo2O4@rGO modified electrode prepared by the wet chemical method showed an improved electrochemical behavior for determination of VEN in pharmaceuticals and human plasma with high recovery results in the range of 96.7–98.6% and 96.0–100.7%, respectively without any interference from the co-existing components.

Teicoplanin (TEIC) and vancomycin hydrochloride (VAN) are glycopeptide antimicrobial drugs against methicillin-resistant Staphylococcus aureus and Gram-positive organisms. So, simple, quick, cost-effective and ultrasensitive spectrofluorimetric method was developed and bio-analytically validated for assay of TEIC and VAN. The proposed method is based on the reaction of acetylacetone with primary amine moiety in the presence of formaldehyde producing highly fluorogenic product measured at 485 nm (λex at 420 nm). The calibration range was constructed from (50–400 ng mL−1) and (70–800 ng mL−1) for TEIC and VAN, respectively. The presented method exhibited low LOD (7.04 and 3.55 ng mL−1) and LOQ (21.33 and 10.77 ng mL−1) values for TEIC and VAN, respectively. The presented method was effectively applied to determine TEIC and VAN in real human plasma with percentage of recovery ranged from 95.57 ± 2.06% to 97.43 ± 1.66% for the studied drugs. Also, the developed method was applied for the first time to study synthetic mixtures of the studied drugs with rifampicin (RIF), as a combination therapy to treat drug-resistant strains of Staphylococcus aureus without interferences from RIF. The synthetic mixtures of TEIC or VAN with RIF were prepared in three different ratios in order to measure the stability of the studied drugs TEIC or VAN in presence of RIF in pure forms and human plasma.

Teicoplanin (TEIC) and vancomycin hydrochloride (VAN) are glycopeptide antimicrobial drugs against methicillin-resistant Staphylococcus aureus and Gram-positive organisms. So, simple, quick, cost-effective and ultrasensitive spectrofluorimetric method was developed and bio-analytically validated for assay of TEIC and VAN. The proposed method is based on the reaction of acetylacetone with primary amine moiety in the presence of formaldehyde producing highly fluorogenic product measured at 485 nm (λex at 420 nm). The calibration range was constructed from (50–400 ng mL−1) and (70–800 ng mL−1) for TEIC and VAN, respectively. The presented method exhibited low LOD (7.04 and 3.55 ng mL−1) and LOQ (21.33 and 10.77 ng mL−1) values for TEIC and VAN, respectively. The presented method was effectively applied to determine TEIC and VAN in real human plasma with percentage of recovery ranged from 95.57 ± 2.06% to 97.43 ± 1.66% for the studied drugs. Also, the developed method was applied for the first time to study synthetic mixtures of the studied drugs with rifampicin (RIF), as a combination therapy to treat drug-resistant strains of Staphylococcus aureus without interferences from RIF. The synthetic mixtures of TEIC or VAN with RIF were prepared in three different ratios in order to measure the stability of the studied drugs TEIC or VAN in presence of RIF in pure forms and human plasma.

The present work is carried out for the synthesis and evaluation of some new 1,3,4-thiadiazolines, 1,3-thiazolines and 1,3-thiazolidin-4-ones linked to 1,2,4-triazolo[1,5-a]benzimidazole as anti-inflammatory agents. Structure elucidation of these compounds was confirmed by IR, 1H-NMR, and mass spectrometry along with elemental microanalyses. All new compounds were tested for their anti-inflammatory activity in comparison to indomethacin (INM) where some of them showed promising results comparable to INM at 4 hours interval. The most active anti-inflammatory compounds (4b, 8c and 9a) were examined on gastric mucosa and didn’t show any gastric ulcerogenic effect compared with the reference INM. Moreover, LD50 of compounds (4b and 9a) were determined in mice; they were found non toxic up to 400 mg Kg–1 (i.p.). Also, docking simulation of some compounds into PLA2 active sites was studied.