Hybrid consensus and k-nearest neighbours (kNN) strategies to classify dual BRD4/PLK1 inhibitors.

A novel decision-making procedure is proposed here for the first time to identify active/inactive and selective/non-selective dual inhibitors using consensus approaches and pools of k-nearest neighbours (kNN) classifications instead of individual models. Dual BRD4/PLK1 inhibition with adequate selectivity is a potential therapeutic strategy for targeting tumour cells in high-risk patients. We report the unique way to identify both active and selective dual BRD4/PLK1 inhibitors using consensus and kNN strategies together with two sources of receptor-based and ligand-based information which are the ranked binding energies of residues and important molecular features, respectively. The results of consensus approaches were compared with the results of individual kNN models. The chemical space similarity was measured using three different distance functions to increase the reliability. All activity and selectivity classification models were validated using cross-validation and y-randomization tests. The outcomes show that consensus approaches can increase the reliability and accuracy of active/inactive or selective/non-selective detections up to 90%. Consensus approaches also reached more balanced values of sensitivity and specificity compared to the individual kNN models because of the compensation in the integration of diverse sources of information.

The effect of synthesis parameters on the geometry and dimensions of mesoporous hydroxyapatite nanoparticles in the presence of 1-dodecanethiol as a pore expander.

Mesoporous hydroxyapatite with different pore diameters and pore volumes were synthesized by the self-assembly method using Cetyltrimethylammonium bromide (CTAB) as the cationic surfactant and 1-dodecanethiol as the pore expander at different micellization pHs, solvent types and surfactant concentrations. Results of field emission scanning electron microscopy (FESEM) showed a decrease in length/diameter ratio of rod-like particles by an increase in micellization pH and also a sphere to rod transition in morphology by an increase in CTAB concentration. Brunauer-Emmett-Teller (BET) surface area and Low angle X-ray diffraction analysis revealed that the optimized mesoporous hydroxyapatite with controlled pore structure can be obtained under basic micellization pH (about 12, pH of complete ionization of 1-dodecanethiol) by using water as the solvent and a high content of cationic surfactant. The results also show that micellization pH has a strong effect on pore structure and changing the pH can shift the mesostructure to a macroporous structure with morphological changes.

In vitro antibacterial evaluation of sol-gel-derived Zn-, Ag-, and (Zn + Ag)-doped hydroxyapatite coatings against methicillin-resistant Staphylococcus aureus.

Hydroxyapatite (HAp) coatings were applied using sol-gel method. Phosphor pentoxide and calcium nitrate were used as phosphorous and calcium precursors, respectively. Zinc nitrate and silver nitrate were used as substitute of calcium in HAp structure. As a base concentration, 1.5 wt %Ag and 2.5 wt %Zn were used. The weight percent of Ag was increased at 0.3 wt% and Zn content was scaled down at 0.5 wt%. Phase analysis and chemical bonds of synthesized materials were studied by XRD and FTIR. Antibacterial activity of Ag- and Zn-doped samples against methicilin-resistant Staphylococcus aureus (MRSA) were assessed by the plate-counting method. The XRD and FTIR results proved formation of HAp compound. Colony counting showed that silver and zinc ions prevent proliferation and growth of MRSA. Interestingly, co-presence of metal ions improves the antibacterial effectiveness of the coatings and the combined effect was greater than sum of the individual effects when each was administered alone. Overall, synergism between antibacterial activities of Zn(2+) and Ag(+) ions against MRSA can be suggested. Thus, cell toxicity decreases and biocompatibility increases without any decrement in antibacterial activity.

Epidemiological study of gastro-oesophageal reflux disease: reflux in spouse as a risk factor.

BACKGROUND: Gastro-oesophageal reflux disease (GERD) is a growing health-care problem with variable distribution. AIM: To assess GERD prevalence and risk factors and their possible correlation with pathophysiology in a population-based study. METHODS: Individuals aged 18-65 years were enrolled through random cluster sampling in Tehran. Previously validated self-administered questionnaires were used. RESULTS: Of the 2500 questionnaires, 2057 were analysed (mean age: 34.8 +/- 13.0 years, 55.1% female). Frequent GERD was seen in 18.2%. Minor symptoms increased prevalence. Female gender (OR: 1.55, 95% CI: 1.01-2.41), BMI >30 kg/m(2) (OR: 1.79, 95% CI: 1.03-3.12), less education (OR: 1.52, 95% CI: 1.02-2.27), smoking (OR: 1.83, 95% CI: 1.12-2.99), NSAID use (OR: 4.23, 95% CI: 1.66-10.74) and GERD in spouse (OR: 1.82, 95% CI: 1.18-2.82) were associated with frequent GERD on multivariable analysis. GERD in first-degree relatives (OR: 1.73, 95% CI: 1.23-2.43) and asthma (OR: 4.09, 95% CI: 1.27-13.15) correlated with infrequent GERD. Minor symptoms correlated with GERD history in first-degree relatives, coffee consumption and NSAID use. Prevalence in the past 3 months was similar to that in the past 12 months (P < 0.05). CONCLUSIONS: Gastro-oesophageal reflux disease is common in Tehran. The association of 'infrequent symptoms' with GERD history in first-degree relatives and 'frequent symptoms' with GERD history in spouse may point to the presence of yet unknown precipitating environmental factors inducing GERD in a genetically susceptible host. Minor GERD symptoms seem to have independent contribution to GERD. Assessing GERD in the past 3 months predicts prevalence in the past year.