NORMAL VASCULAR REACTIVITY IS RESTORED BY APIGENIN IN DIABETIC RATS

Objective: Diabetes is a disease whose complications have serious implications for the health of sufferers; one of the most serious such complications is the deterioration of vascular reactivity. Apigenin is a natural flavonoid with PKC inhibiting and antioxidant properties. In this study, the impact of apigenin on vascular reactivity deterioration was investigated.Methods: Insulin resistance (IR) and insulin deficiency (ID) were induced by fructose and streptozotocin respectively. The isolated aortae vasoconstriction response to phenylephrine (PE) and potassium chloride (KCl) in addition to the vasodilation response to acetylcholine (ACh) and sodium nitroprusside (SNP) were tested.Results: IR and ID were associated with significantly exaggerated vasoconstriction to KCl and PE while significantly impaired vasodilation to ACh. Response to SNP was not significantly affected by both IR and ID. In vitro incubation with apigenin (7 7µM) for 20 min restored normal responses to PE, KCl and ACh in aortae isolated from insulin-resistant or insulin-deficient rats. Incubation for one hour with the PKC stimulant, phorbol 12-myristate 13-acetate (PMA, 800 nM) resulted in aortic impairment similar to that seen in aortae isolated from IR and ID animals. Incubation with both apigenin prevented PMA-induced exaggerated vasoconstriction response to both PE and KCl.Conclusion: Apigenin alleviates vascular exaggerated vasoconstriction and impaired dilation associated with diabetes or PKC activated

Nanocrystalline Na0.1V2O5.nH2Oxerogel Thin Film for Gas Sensing

Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel obtained by sol-gel synthesis was used as a gas sensor. Gas sensing properties of different gases such as hydrogen, petroleum and humidity were investigated. Applying XRD and TEM the size of the nanocrystals is found to be 7.5 nm. SEM shows a highly porous structure with submicron meter-sized voids present throughout the sample. FTIR measurement shows different chemical groups identifying the obtained series of gels. The sample was n-type semiconductor according to the thermoelectric power and electrical conductivity. It can be seen that the sensor response curves from 130°C to 150°C show a rapid increase in sensitivity for all types of gas injection, low response values for heating period and the rapid high response values for cooling period. This result may suggest that this material is able to act as gas sensor during the heating and cooling process

Nanocrystalline Na0.1V2O5.nH2Oxerogel Thin Film for Gas Sensing

Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel obtained by sol-gel synthesis was used as a gas sensor. Gas sensing properties of different gases such as hydrogen, petroleum and humidity were investigated. Applying XRD and TEM the size of the nanocrystals is found to be 7.5 nm. SEM shows a highly porous structure with submicron meter-sized voids present throughout the sample. FTIR measurement shows different chemical groups identifying the obtained series of gels. The sample was n-type semiconductor according to the thermoelectric power and electrical conductivity. It can be seen that the sensor response curves from 130°C to 150°C show a rapid increase in sensitivity for all types of gas injection, low response values for heating period and the rapid high response values for cooling period. This result may suggest that this material is able to act as gas sensor during the heating and cooling process

Improvement of drought tolerance in five different cultivars of Vicia faba with foliar application of ascorbic acid or silicon

Aim of study: To explore the role of ascorbic acid (AsA) or silicon (Si) in improving drought tolerance in five faba bean cultivars under irrigation water deficit (IWD).Area of study: The experimental farm; 30° 36′ N, 32° 16′ E, Egypt.Material and methods: Three drip irrigation regimes (WW, well-watered, 4000 m3 water ha-1; MD, moderate drought, 3000 m3 water ha-1; and SD, severe drought, 2000 m3 water ha-1) were applied to plants, which were sprayed 25, 40, and 55 days after sowing with 1.5 mM AsA or 2.0 mM Si vs distilled water as a control.Main results: Drought negatively affected physiological attributes (photosynthetic pigments, gas exchange parameters, relative water content, membrane stability index, electrolyte leakage (EL), and lipid peroxidation), which restricted plant growth and yields, and stimulated alterations in both enzymatic and non-enzymatic antioxidant activities. However, AsA or Si application mitigated drought effects on physiological attributes, improving growth, yields and water use efficiency by raising antioxidant activities and suppressing lipid peroxidation and EL in stressful cultivars. The mitigating effects of AsA and Si were more pronounced under MD.Research highlights: ‘Nubaria-2’, ‘Giza-843’, and ‘Sakha-3’ were more tolerant than ‘Giza-716’ and ‘Sakha-4’, suggesting the use of AsA or Si to ameliorate the IWD effects on stressful cultivars. Certain physiological traits exhibited positive association with growth and seed yield, demonstrating their importance in enhancing seed yield under irrigation treatments

Role of Sulfur as a Reducing Agent for the Transition Metals Incorporated into Lithium Silicate Glass

Li2O·0.25Fe2O3·0.25NiO·1.5SiO2 glass was prepared with and without 5 wt % sulfur (S) while melting the mixture of the starting materials at 1350 °C for 1 h in air. A part of the as-prepared glass was heat treated for 1 h near its crystallization temperature (Tc) as determined from differential thermal analysis. Each glass was also investigated by means of Mössbauer spectroscopy, X-ray diffraction, FTIR, and DC conductivity. The Mössbauer spectra showed ionic Fe2+ and Fe3+ species in the glass as well as in the precipitated phase obtained after heat treatment. XRD patterns demonstrated the glassy phase formation in the as-quenched samples irrespective of the presence of sulfur. The heat treated samples showed different precipitated phases containing iron particles of nanometer size. The electric conductivity measurements showed that sulfur-doped samples had high values of (σ) probably because of small polaron hopping between Fe2+ and Fe3+

Silver-Doped Cadmium Selenide/Graphene Oxide-Filled Cellulose Acetate Nanocomposites for Photocatalytic Degradation of Malachite Green toward Wastewater Treatment

Silver-doped cadmium selenide/graphene oxide (GO) (Ag-CdSe/GO) nanocomposites have been synthesized, loaded in cellulose acetate (CA) to form Ag-CdSe/GO@CA heterostructure nanofibers, and characterized in terms of structural, morphological, photocatalytic properties, among others. The photocatalytic degradation of malachite green (MG) was estimated using cadmium selenide-filled CA (CdSe@CA), silver-doped cadmium selenide-filled CA (Ag-CdSe@CA), cadmium selenide/GO-filled CA (CdSe/GO@CA), and silver-doped cadmium selenide/GO-filled CA (Ag-CdSe/GO@CA) nanocomposite materials. The Ag-CdSe/GO@CA nanocomposites exhibit and retain an enhanced photocatalytic activity for the degradation of MG dye. This amended performance is associated with the multifunctional supporting impacts of GO, Ag, and CA on the composite structure and properties. The superior photocatalytic activity is related to the fact that both Ag and GO can act as electron acceptors that boost the separation efficiency of photogenerated carriers and the loading of the combined nanocomposite (Ag-CdSe@GO) on CA nanofibers, which can augment the adsorption of electrons and holes and facilitate the movement of carriers. The stability of Ag-CdSe/GO@CA nanocomposite photocatalysts demonstrates suitable results even after five recycles. This study establishes an advanced semiconductor-based hybrid nanocomposite material for efficient photocatalytic degradation of organic dyes.The Academy of Scientific Research and Technology (ASRT), Egypt, Grant No. 6510, supported this project financially

Rituximab versus cyclophosphamide as first steroid sparing agent in childhood frequently relapsing and steroid dependent nephrotic syndrome

Background: Approximately 50% of children with steroid-sensitive nephrotic syndrome (SSNS) will suffer from frequent relapses or steroid dependency, prompting the use of so-called steroid-sparing drugs. In this pilot study, we compare the efficacy and safety of rituximab to oral cyclophosphamide as first-line steroid-sparing medications. Methods: A prospective open-label non-randomized study of children with frequent relapsing or steroid-dependant SSNS. Exclusion criteria were steroid-resistant disease, prescription of immunosuppressive agents other than prednisolone or levamisole, evidence of impaired kidney function, leucopenia, or active infection. The recruited children were allocated either to the oral cyclophosphamide (3 mg/kg/day for 8 weeks) or intravenous rituximab treatment (two doses of 375 mg/m2/dose, 2 weeks apart) and were monitored for relapses and side effects for 12 months. Results: Forty-six subjects were included from two centers; 27 received cyclophosphamide and 19 received rituximab. One-year relapse-free survival was reached in 17 (58.6%) patients treated with cyclophosphamide compared to 16 (84.2%) with rituximab (adjusted HR 0.36; 95% CI 0.09–1.45; p = 0.151). The mean interval to relapse was 6.9 months in the cyclophosphamide group (N = 10) and 6.3 months in the rituximab group (N = 3). Both treatments were associated with a significant (p < 0.001) reduction in prescribed dose of oral alternate-day steroid from 1.02 to 0.36 mg/kg (cyclophosphamide) and 0.86 to 0.08 mg/kg (rituximab). Importantly, a significantly (p = 0.003) higher percentage of patients achieved complete withdrawal of steroid within 3 months of commencing study treatment in the rituximab (73.7%) versus cyclophosphamide (29.6%) group. Transient leucopenia was the most frequent adverse effect observed in the cyclophosphamide group (18.5%) and one patient (3.4%) had acute hepatotoxicity besides severe leucopenia and neutropenia in the 7th week of treatment with complete recovery with the withdrawal of cyclophosphamide and maintenance of remission. A minor infusion-related reaction in the form of a generalized macular skin rash was observed in one patient (5%) in the rituximab group. Conclusions: Rituximab is non-inferior to cyclophosphamide and safe as a first-line steroid-sparing agent in children with SSNS. A larger multicenter study is required to assess superiority over cyclophosphamide

Stripping voltammetric methods for determination of the antiparasitic drug nitazoxanide in bulk form, pharmaceutical formulation and human serum

Cyclic voltammograms of nitazoxanide recorded at the hanging mercury drop electrode in the Britton-Robinson universal buffer of pH values 2 to 11 containing 20% (v/v) ethanol exhibited a single 4-electron irreversible cathodic peak corresponding to the reduction of its NO2 group to the hydroxylamine stage. Nitazoxanide was found to adsorb onto surface of the mercury electrode in a monolayer surface coverage of 3.16&#215;10-10 mol cm-2 in which each adsorbed molecule occupies an area of 0.525 nm². Based on its adsorption behavior onto the mercury electrode surface, validated linear sweep (LS), differential pulse (DP) and square wave (SW) adsorptive cathodic stripping voltammetric methods were described for determination of bulk nitazoxanide. Limits of detection of 1.5&#215;10-10, 2.4&#215;10-10 and 3.0&#215;10-11 mol L-1 and limits of quantification of 5.0&#215;10-10, 8.0&#215;10-10 and 1.0&#215;10-10 mol L-1 nitazoxanide in the bulk form were achieved by means of the described LS, DP and SW adsorptive cathodic stripping voltammetric methods, respectively. The described methods were successfully applied for determination of nitazoxanide in its pharmaceutical formulation (Cryptonaz powder) and in spiked human serum without the necessity for sample pretreatment, time consuming extraction steps or formation of colored chromogens prior to the analysis. Besides, nitazoxanide was successfully determined without interference from its acid or base-induced degradation products indicating the stability-indicating power of the described voltammetric methods