Antecedents of work-family conflict among Egyptian civil workers.

AIM: Previous studies have suggested variable levels of associations between work-family conflict (W_F_C) and its antecedents in different populations. We aimed to assess the antecedents of this conflict and its two types; work-to-family (WFC) and family-to-work (FWC) among Egyptian civil workers. SUBJECTS AND METHODS: In a convenience sample of 3134 Egyptian civil workers, we assessed the W_F_C using the National Study of Midlife Development in the US and attributed it, by logistic and linear regression analyses, to several sociodemographic, work/family situational, behavioral, and health-related variables which were collected by a questionnaire survey between October 2019 and January 2020. RESULTS: W_F_C was prevalent in 56% of the sample (51% for WFC and 62% for FWC). The work and family situational factors were the most significant antecedents of the W_F_C and its two types; partial R 2 was 0.71. Both the health-related and behavioral clusters of antecedents were also predictors of W_F_C, while the sociodemographic antecedents contributed minimally to the FWC. The multivariable odds ratios (95% CIs) for high W_F_C in those with high vs low work demands, job control, social support at work, and family were 4.11 (2.89-7.03), 0.0 (0.66-0.90), 0.86 (0.62-0.98), and 0.74 (0.59-0.94), respectively. CONCLUSIONS: Work and family situational factors were the most significant antecedents of the levels of W_F_C in Egyptian civil workers. The Egyptian authorities could reduce the civil workers' W_F_C by improving the work environment, finding ways to relieve the workload demands, and helping the civil workers to have more job control and social support.

Storage Mite Infestation of Dry-Stored Food Products and Its Relation to Human Intestinal Acariasis in the City of Minia, Egypt.

Initial data on the prevalence of storage mites in dry-stored food products and estimates of the presence of mites in human stool in the city of Minia, Egypt are provided. In total, 847 samples were collected randomly from houses and retail stores between March 2017 and February 2018. In addition, 1,000 human stool samples were collected for the detection of the presence of mites. Mites were extracted from 285 of 840 (33.9%) samples, and mite contamination was found to be most prevalent in wheat flour (73.3%). In total, 11 mite species belonging to six families were identified, with the pest species Tyrophagus putrescentiae (Schrank) (Acari: Acaridae) (TP) being the most prevalent (91.2% of samples). The seasonal density distribution showed the highest storage mite density in March-April, followed by October, and the lowest in January. In addition, mites were detected in 87 (8.7%) human stool samples, with significant associations between certain occupations and some personal characteristics. Therefore, more attention needs to be paid to intestinal acariasis arising from mite infestation of dry-stored food products.

Targeting anticancer drugs to the brain: II. Physiological pharmacokinetic model of oxantrazole following intraarterial administration to rat glioma-2 (RG-2) bearing rats.

The disposition of the anticancer drug oxantrazole (OX) was characterized in rats bearing the rat glioma-2 (RG-2) brain tumor. Following intraarterial administration of 3 mg/kg of OX, serial sacrifices were completed from 5 min to 5 hr after administration. Blood and tissue samples collected at the time of sacrifice were processed and measured for OX concentrations by HPLC. The kidney had the greatest affinity for OX with the Cmax being 40.6 micrograms/ml at 15 min after administration. OX concentrations in brain tumor were higher than in normal right and left brain hemispheres, and consistent with enhanced drug blood-tumor barrier (BTB) permeability seen in experimental models for brain tumors. Observed heart, liver, lung, and spleen OX concentrations were similar, ranging from approximately 2 micrograms/ml to 20 micrograms/ml. A unique technique was used to develop a global physiological pharmacokinetic model for OX. A hybrid or forcing function method was used to estimate individual tissue compartment biochemical parameters (i.e., partition and mass transfer coefficients). A log likelihood optimization scheme was used to determine the best model structure and parameter sets for each tissue. Most tissues required a 3-subcompartment structure to adequately describe the observed data. The global model was then reconstructed with an arterial blood and rest of body compartments that provided predicted OX concentrations in agreement with the data. The model development strategy provides a systematic approach to physiological pharmacokinetic model development.

Targeting anticancer drugs to the brain. I: Enhanced brain delivery of oxantrazole following administration in magnetic cationic microspheres.

A magnetic cationic microsphere delivery system, prepared from the polysaccharide chitosan and containing oxantrazole (OX), was examined for its ability to enhance brain delivery of OX compared to administration of OX in solution (OX-S). Magnetic chitosan microspheres containing OX (MCM-OX) and OX-S were administered intraarterially to male Fischer 344 rats at OX doses of 0.1 mg/kg and 0.5 mg/kg with a magnetic field of 6000 G applied to the brain for 30 min. Animals were sacrificed at 30 min and 120 min after MCM-OX and OX-S treatments, and multiple tissues were collected and analyzed for OX by HPLC. A statistical analysis of the effects of treatment, OX dose, and time on total OX in each sampled tissue was made. MCM-OX significantly increased OX brain concentrations compared to those achieved with OX-S treatments, concentrations after MCM-OX being a minimum of 100-fold greater. Within the MCM-OX treatment groups, ipsilateral OX concentrations were much greater, indicating target organ selectivity. A most interesting finding was that OX brain concentrations were similar at 120 min and 30 min after MCM-OX treatment. Thus, even in the absence of the magnetic field, MCM-OX were retained in the brain, possibly through cationic-anionic interactions with the blood-brain barrier.

High-performance liquid chromatographic analysis of the anticancer drug oxantrazole in rat whole blood and tissues.

A reversed-phase high-performance liquid chromatographic (HPLC) assay was developed for the antitumor anthrapyrazole analogue, oxantrazole (OX), in rat whole blood and tissues. Blood samples were mixed with equal volumes of a 25% (w/v) aqueous solution of L-ascorbic acid, whereas tissue samples were homogenized with 1.5-3 volumes of an L-ascorbic acid-methanol-water (1:10:1, w/v/v) mixture to prevent oxidative degradation of OX. Samples were then treated with 60% (v/v) perchloric acid (25-30 microliters/ml of stabilized sample) to precipitate proteins, and centrifuged, with the resultant supernatants analyzed on HPLC utilizing a C8 column. The mobile phase for blood and urine samples consisted of 8% (v/v) glacial acetic acid, 13% (v/v) acetonitrile, 79% (v/v) water, 0.16% (w/v) sodium acetate, and 0.05% (w/v) L-ascorbic acid (final pH 2.7), and was pumped at 1.8 ml/min. Tissue samples were eluted at 2 ml/min with a mobile phase consisting of 8% (v/v) glacial acetic acid, 12% (v/v) acetonitrile, 80% (v/v) water, 0.16% (w/v) sodium acetate, and 0.0;5% (w/v) L-ascorbic acid. OX and internal standard were detected at 514 nm and had retention times of 2.3 and 3.1 min, respectively. The limit of quantitation of OX was 25-50 ng/g. Recovery of OX from biological samples ranged from 50 +/- 0.9% in spleen to 102.8 +/- 1.8% in RG-2 glioma. The analytical method was applied to a pharmacokinetic study in rats.

Optimized formulation of magnetic chitosan microspheres containing the anticancer agent, oxantrazole.

A combined emulsion/polymer cross-linking/solvent evaporation technique was used to prepare magnetic chitosan microspheres (MCM) containing the anticancer drug, oxantrazole. A central composite experimental design was used to simultaneously evaluate a variety of formulation factors on a number of response variables, such as the percentage of oxantrazole entrapped in the MCM. In association with the study design, statistical optimization procedures indicated the factors that significantly influence MCM preparation and what levels of the factors are needed to produce optimum MCM. Entrapment of anticancer agents into biodegradable microspheres is difficult because of low aqueous drug solubility and porosity of the particles. The latter effect was circumvented by a chitosan cross-linking step that resulted in approximately 3% (w/w) oxantrazole entrapment in the MCM via the optimization procedures. The combined formulation and statistical optimization strategy provide a basis to develop other microparticulate systems and led to a dosage form that can be used for future in vivo investigations.

A simple rheological method for the in vitro assessment of mucin-polymer bioadhesive bond strength.

A simple viscometric method was used to quantify mucin-polymer bioadhesive bond strength. Viscosities of 15% (w/v) porcine gastric mucin dispersions in 0.1 N HCl (pH 1) or 0.1 N acetate buffer (pH 5.5) were measured with a Brookfield viscometer in the absence (eta m) or presence (eta t) of selected neutral, anionic, and cationic polymers (0.1-2.5%, w/v). Viscosity components of bioadhesion (eta b) were calculated from the equation, eta t = eta m + eta p + eta b, where eta p is the viscosity of corresponding pure polymer solution as measured by an Ostwald viscometer. The forces of bioadhesion (F) were calculated from the equation, F = eta b sigma, where sigma is the rate of shear/sec. eta b's and F's for polyelectrolytes, e.g., polyacrylic acid, cationic gelatin, and chitosan were always higher in acetate buffer than in HCl. Validity of the technique and the effect of ionic charge, polymer conformation, and rate of shear on eta b and F are discussed, as is a comparison of this method to other methods for evaluating bioadhesive materials.

Receptor-mediated magnetic carriers: basis for targeting.

A new magnetic microsphere carrier has been formulated that may localize drugs by both biochemical and physical means. The microspheres, prepared from the polysaccharide chitosan, are designed to bind to anionic glycosaminoglycan receptors on the surface of capillary endothelial cells. The microspheres were formulated to have a controlled cationic character and had a mean diameter of 0.70 micron and a magnetite content of 16% (w/w). Formation of complexes between chitosan and heparin and between the microspheres and heparin has been demonstrated. Heparin served as a model glycosaminoglycan. The chitosan:heparin complex ratio was found to be 1:1 based on charge and was formed between ammonium ions on the chitosan and SO3- groups on heparin. Neutralization of the charge on the microspheres prevented their complexation with heparin. The rationale for the use of the delivery system and its potential limitation are discussed.