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In this study, green zinc oxide (ZnO)/polypyrrole (Ppy)/cellulose acetate (CA) film has been synthesized via solvent casting. This film was used as supporting material for glucose oxidase (GOx) to sensitize a glucose biosensor. ZnO nanoparticles have been prepared via the green route using olive leaves extract as a reductant. ZnO/Ppy nanocomposite has been synthesized by a simple in-situ chemical oxidative polymerization of pyrrole (Py) monomer using ferric chloride (FeCl3) as an oxidizing agent. The produced materials and the composite films were characterized using X-ray diffraction analysis (XRD), scanning electron microscope (SEM), Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA). Glucose oxidase was successfully immobilized on the surface of the prepared film and then ZnO/Ppy/CA/GOx composite was sputtered with platinum electrode for the current determination at different initial concentrations of glucose. Current measurements proved the suitability and the high sensitivity of the constructed biosensor for the detection of glucose levels in different samples. The performance of the prepared biosensor has been assessed by measuring and comparing glucose concentrations up to 800 ppm. The results affirmed the reliability of the developed biosensor towards real samples which suggests the wide-scale application of the proposed biosensor. [ABSTRACT FROM AUTHOR]

In this work, mixing polyvinyl alcohol (PVA), chitosan (CS) and polyaniline (PANI) to prepare composite nanofibers with improved adsorption capacity using electrospinning technique has been studied, Thereby overcoming the difficulty of producing PANI nanofibers. The morphologies of the prepared nanocomposites were fully examined by SEM, Fourier transform infrared spectroscopy and X-ray diffraction measurements. Results indicated that the blended PVA/CS/PANI-based nanofibers exhibited better size morphology with smaller diameter than (PVA/PANI) and pure polyaniline. Batch experiments were conducted using the prepared (PVA/PANI/CS) composite to study its affinity for dye decolorization. Different factors affecting the adsorption process such as contact time, initial dye concentration, temperature and pH were optimized. The maximum percentage removal was found to be 96% at 300 rpm using adsorbent dose of 60 mg and temperature of 25°C and initial dye concentration 50 ppm. Also, the adsorption isotherms, kinetics and thermodynamics for the removal process were studied. The adsorption process followed Freundlich isotherm and pseudo-first order kinetics. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO-NPs) were successfully synthesized using both biological and chemical techniques. This study is mainly focused on the green synthesis (biological) method of ZnO-NPs using different plant leaf extracts from leaves of guava, olive, fig, and lemon. The plant leaf extracts (polyphenols) act as reductants and zinc nitrate hexahydrate (Zn(NO3)2.6H2O) acts as a precursor. Chemical synthesis method of ZnO-NPs was carried out using prepared sodium hydroxide and zinc nitrate. The produced ZnO-NPs were characterized using X- ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), fourier transform infrared (FTIR), Thermal gravimetric analysis (TGA), and particle size analysis (PSA). The average crystallite size of green-synthesized zinc oxide nanopowders range from 7.1 to 28 nm, while the average crystallite size of chemical-synthesized zinc oxide powders range from 19.6 to 148 nm according to the XRD calculations and TEM observations. Both ZnO nanopowders showed high thermal stability up to 600 °C. The green-synthetized ZnO-NPs were evaluated for phenol decontamination in polluted wastewater. The maximum recorded phenol removal was 99.7% within 250 minutes using 0.1g ZnO-NPs, making ZnO-NPs a promising adsorbent material for phenol decontamination in polluted wastewater. [ABSTRACT FROM AUTHOR]

Rosemary (Rosmarinus officinalis; RM) and thyme (Thymus vulgaris; TV) are used as remedies. We designed this work to investigate the preventive effect of aqueous extracts of RM or TV on the gentamicin (GM)-induced hepatotoxicity and abnormalities of lipid profile in rats. Both plant extracts exhibited an in vitro antioxidant activity as determined by the 1,1-diphenyl-2-picrylhydrazyl assay. Radical scavenging activity for TV extract was 48.7% and for RM extract was 25.6%. Polyphenolic determination by high-performance liquid chromatography for both extracts revealed that catechin, coumarin, cinnamic acid and rutin were detected in both extracts. RM extract had higher values than TV extract in all except rutin. Ferulic acid and quercetin were also detected in TV extract and sinapic acid and oleuropein were detected in RM extract. In rats given GM intraperitoneally for 10 days and coadministered either RM extract or TV extract orally, both aqueous extracts demonstrated similar hepatoprotective effects manifested by approximate normalization of plasma liver enzymes (AST and ALT), bilirubin level and total protein concentration compared with the group given GM only. Abnormal lipid parameters and raised hydrogen peroxide levels were ameliorated by both extracts. Pancreatic lipase activity was markedly reduced by RM extract. Also, the atherogenic index value was significantly reduced by both extracts as compared to that of GM group. DNA fragmentation analysis confirmed tissue damage by GM and its amelioration by the extracts. These findings suggest that RM and TV extracts could be helpful in ameliorating some aspects of gentamicin toxicity. [ABSTRACT FROM AUTHOR]

This study aims to the enhancement of Cu2+ ions removal from wastewaters and recovery of the metal value by cementation on a longitudinal finned rotating zinc cylinder. The effect of different parameters such as cylinder rotational speed (rpm), initial Cu2+ ions concentration and the effect of the fin height to cylinder diameter (e/d) on the rate of Cu2+ ions cementation was investigated. In addition, the effect of drag reducing polymer on the rate of Cu2+ cementation was examined. The rate of cementation was expressed in terms of the mass transfer coefficient. The results revealed that the mass transfer coefficient increases with increasing rpm, initial Cu2+ concentration and e/d ratio. The present results show that finned rotating cylinder enhances rate of cementation compared to smooth rotating cylinder by percentage ranges from 28.79 to 134.85 depending on the operating conditions. On the other hand, the presence of drag reducing polymer retards the rate of cementation. The present data fit the following dimensionless equations: For smooth cylinder: Sh = 0.74 Re0.69 Sc0.33. For finned rotating cylinder: Sh = 0.38 Re0.9 Sc0.33 (e/d) 0.25. The importance of the above correlations in the design and operation of industrial-scale rotating cylinders cementation reactors was pointed out. [ABSTRACT FROM AUTHOR]

The immune system protects the host against pathogenic organisms and acts to ensure tolerance to self, to food and environmental components. Bovine milk, micronutrients and many nutrients beneficially affect the host immunity. Bovine milk has many components that improve the body immune functions. In addition, a significant mass of research now exists investigating the role of probiotic and prebiotic in ameliorating immunity during various intestinal diseases. Vitamins and minerals boost immunity. Micronutrient deficiency suppresses immune function by affecting the innate T-cell mediated immune response and adoptive antibody response. Moreover essential fatty acids, and some amino acids have numerous important influences on immune responses. Besides, glutathione and nucleotides are important components of immunonutrient mixes. Also, in this article, an overview of how nutrient-nutrient interaction may affect host immunity, was discussed. [ABSTRACT FROM AUTHOR]

Objective: Diabetes mellitus (DM) and hypercholesterolemia (HC) when poorly controlled lead to debilitating central nervous system complications including cognitive deficits and memory impairment. In the present study, we investigated the mechanisms that may be responsible for such deficits. Methods: Both diabetes and HC were induced in two groups of rats independently using alloxan and high cholesterol diet, respectively. Results: Acetyl cholinesterase was significantly increased in brain of diabetic rats. Also, brain malondialdehyde level was extremely elevated in both diabetic and hypercholesterolemic groups. Meanwhile, brain albumin was markedly decreased in both of them. However, the brain iron level was significantly increased in DM with concomitant increase in total antioxidant capacity in the same group as compared to the normal control. The concentration of brain calcium was noticeably increased in HC group. Our results were confirmed by the increased activity of lactate dehydrogenase in both DM and HC groups, indicating major brain cytotoxicity. Conclusions: Overall, our results suggested that both DM and HC have deleterious effects on the brain which may be attributed to oxidative stress and dysregulation of both cholinergic function and calcium level. Administration of antioxidant is recommended in both cases. [ABSTRACT FROM AUTHOR]

The main concern of this study is to test the ability of some fungi isolated from Sinai Peninsula carbonaceous shales to perform microbial leaching of rare earth elements (REEs) from these rocks. Two methods of REEs bioleaching were tested using both direct (active) and indirect (passive) processes. Direct bioleaching process of carbonaceous shale samples was found to be more effective than indirect process for all tested microorganisms. Bioleaching efficiency of REEs using different fungal strains increases with decreasing REEs concentrations when their growth rate decreases. Strains of Aspergillus (A. niger and A. flavus) were found to be the most efficient organisms. The maximum extraction yield of total REEs was 86% at 7days incubation time, 1% pulp density, and 30 °C incubation temperature. A. niger and A. flavus exhibit good potential in generating a variety of organic acids (citric and oxalic) effective for REEs solubilization. Citric and oxalic acids contents produced by A. niger was higher than by A. flavus interpreting higher REEs bioleaching efficiency of A. niger than A. flavus. From properly prepared pregnant bio-leach liquor, the leached REEs were recovered in the form of REEs oxalate product using classical chemical technique. [ABSTRACT FROM AUTHOR]

Tissue factor (TF) is a membranous glycoprotein that activates the coagulation system when blood vessels or tissues are damaged. TF was up-regulated in monocrotaline (MCT)/lipopolysaccharide (LPS) hepatotoxicity model. The present study aimed to test the hypothesis that TF-dependent fibrin deposition occurs in liver toxicity induced by CCl4 in mice. Pericentral deposition of TF and fibrin is induced after CCl4-induced liver toxicity. The toxicity was evaluated by determination of serum activities of ALT, AST and ALP as well as GSH content and histopathological changes. The results showed that injection of mice with TF-antisense deoxyoligonucleotide (TF-AS) prevented the accumulation of TF and fibrin in the hepatic tissues. Furthermore, it significantly restored blood biochemical parameters, GSH content and distorted histopathological features caused by CCl4. The current study demonstrates that TF activation is associated with CCl4-induced liver injury. Furthermore, administration of TF-AS successfully prevented this type of liver injury., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The aim of the present study is to assess the possible protective effects of thymol and carvacrol against cisplatin (CP)-induced nephrotoxicity. A single dose of CP {6 mg/kg, intraperitoneally (i.p.)} injected to male rats revealed significant increases in serum urea, creatinine, and tumor necrosis factor alpha levels. It also increased kidney contents of malondialdehyde and caspase-3 activity with significant reduction in serum albumin, kidney content of reduced glutathione as well as catalase, and superoxide dismutase activity as compared to that of the control group. In contrast, administration of thymol {20 mg/kg, orally (p.o.)} and/or carvacrol (15 mg/kg, p.o.) for 14 days before CP injection and for 7 days after CP administration restored the kidney function and examined oxidative stress parameters. In conclusion, thymol was more effective nephroprotective than carvacrol. Moreover, a combination of thymol and carvacrol had a synergistic nephroprotective effect that might be attributed to antioxidant, anti-inflammatory, and antiapoptotic activities., (© 2014 Wiley Periodicals, Inc.)

Nephrotoxicity is a dose-limiting factor in the use of cisplatin against solid tumours. Methimazole, an antithyroid drug containing a free SH group, has a nephroprotective potential against chemically-induced nephrotoxicity. We tried to explore the nephrotoxic effect of the experimentally therapeutic dose of cisplatin (7 mg kg(-1), i.p.), particularly on the nuclear level of kidney cells in male albino rats, as well as the possible protective effect of methimazole. Furthermore, the drug interaction regarding the oncolytic effect of cisplatin was examined in Ehrlich ascites carcinoma (EAC)-bearing mice. A single dose of cisplatin caused kidney damage, 6 days after injection, manifested by 219% increase in serum creatinine, 384% increase in blood urea nitrogen and 170% increase in kidney content of lipid peroxides. Kidney DNA showed clear fragmentations detected by gel electrophoresis. However, kidney reduced glutathione was unchanged at that time period. Histological examination of kidney confirmed the toxic effect of cisplatin. Methimazole (40 mg kg(-1), i.p., 30 min before cisplatin injection) significantly protected the kidney from the nephrotoxic effect of cisplatin as judged from the biochemical parameters investigated as well as the histopathological examination. On the other hand, the survival data in EAC-bearing mice treated with both drugs indicated the persistence of an effective cytotoxic action. This study points to a promising use of this combination and necessitates further experimental and clinical studies., (Copyright 2000 Academic Press.)

Treatment of pregnant albino rats at gestation day 9 with the dopamine agonist, bromocriptine, in a dose of 0.7 mg kg-1 day-1, i.p. for 11 days produced a significant increase in the normal uterine contractions both in vitro and in vivo. The increase in frequency (F), amplitude (A) and area under the curve (AUC) in the in vitro experiment amounted to 35, 80 and 58%, respectively; while the increase in F and A in the in vivo experiment was 36 and 25%, respectively, in comparison with the corresponding control group. Addition of oxytocin (5x10(-12)-4x10(-11) m) to the uterus isolated from rats pretreated with bromocriptine resulted in marked uterotonic effect (24, 35 and 49% increase in F; 25, 35 and 46% increase in A and 42, 62 and 122% increase in AUC of contractions). Also, the in vivo experiment showed that an injection of oxytocin at the time of investigation (0.125-1.0 I.U. kg-1, i.v.) into rats pretreated with bromocriptine caused a marked increase in F (33, 40 and 81%) and A (33, 37 and 75%) of uterine contractions compared to the values of bromocriptine-treated animals. These results indicate that bromocriptine should be used with caution during pregnancy. In addition, this must be considered when using oxytocin during delivery of females pretreated with bromocriptine., (Copyright 1999 The Italian Pharmacological Society.)

This paper comprises a study of the electrostatic potentials generated on the surface of the scrotal area when different types of textile fabric were worn. 21 healthy volunteers were divided into 3 equal groups. The first group was dressed in underpants made of 100% polyester, the second of 100% cotton, and the third of a 50:50% polyester:cotton mixture. With an electrostatic kilovoltmeter, the electrostatic potentials were measured 1 h after wearing the pants once at daytime and a second time at night. The test was repeated 4 times, each on a separate day. No electrostatic potentials were detected on the cotton underpants. The polyester pants showed the highest potentials (mean 338.9 +/- 25 SD Volt cm-2) while the mixed polyester:cotton pants produced less than half that level (mean 148.3 +/- 16 SD Volt cm-2). The readings at daytime were higher than at night, probably due to the higher temperature during the day. The accumulated electrostatic charges on the pants are due to the friction of the pants with the skin. As a result of friction, equal and opposite charges are accumulated on the skin surface and on the inner surface of the pants facing the skin. Eventually, an 'electrostatic field' is produced traversing the scrotal contents and may disturb the testicles and/or epididymis leading to disordered spermatogenesis.

Action potentials (AP) of neurons A and B could be only elicited in the presence of Na-+ ions. An increase in [Ca-++]0 led to depolarization of neurons, enhancement of their excitability, AP, overshoot, of positive afterpotential, AP duration, AP maximal rate of fall (Vf) and to decrease in AP maximal rate of rise (Vr). After addition of CaCl2 up to 50 mmoles into the Ringer solution, the membrane resistance (R) increased. If the [Na-+]0 was equimolarly diminished, R increased up to the [Ca-++]0 30 mmoles, but at greater [Ca-++]0 R fall below the initial value. The regularities were independent of the initial value of resting potential (RP). At high [Ca-++]0 Ca-++ contributed to the generation of the inward current during AP while Na-+ caused an increase in ionic (calcium) membrane permeability at rest. At high [Ca-++]0, Na-+ was also necessary for support of membrane channels which maintained the inward and outward currents during the AP.

Chlorcholine chloride (CCC) the molecule of which has no other group, characteristic of acetylcholine (Ach), causes an effective cholinomimetic action on the surface membrane of the mollusc neurons A and B. As the concentration of Ach and CCC increases from 10(-6) to 10(-3) M the resting potential (RP) and the membrane resistance (R) of the neuron A first increases then decreases. The increase of Ach and CCC concentration causes in the neuron B only a decrease of the above mentioned parameters. The data point to the necessity of improving the ideas about the structure of cholinoreceptors and mechanism of cholinoreceptor-cholinomimetic interaction.