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Background: Adrenergic beta antagonists are not sufficient to prevent atrial fibrillation after coronary artery bypass graft (CABG). This study was designed to evaluate the effect of ascorbic acid as an adjunct to beta-blockers in prevention of post-CABG atrial fibrillation Methods: Patients who were more than 50 years old and scheduled to undergo CABG were included if they were treated with beta-blockers at least 1 week before surgery. Patients with previous history of atrial fibrillation, AV block, heart rate

Purpose: To evaluate the changes in the enamel surface microhardness following the application of various suspensions of Crest and Pooneh toothpastes with and without fluoride.Materials and Methods: Fifty-six enamel blocks of primary incisors were exposed to a pH-cycling regime consisting of demineralisation and remineralisation solution, then suspensions of the dentifrices Crest 1100, Crest 500, Pooneh 500, Pooneh without fluoride. Changes of the enamel surface microhardness in pre-demineralisation (initial), post-demineralisation (demineralised) and post-remineralisation (final) stages were measured for four groups and were analysed using the Student t test and one-way ANOVA.Results: The percentages of changes in surface microhardness for Crest 1100, Crest 500, Pooneh 500 and Pooneh without fluoride were 45.4, 35.4, 28.6 and 23.7, respectively.Conclusion: Average changes of surface microhardness for Crest 1100 were significantly higher than Crest 500, Pooneh 500 and Pooneh without fluoride. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to compare the stabilizing effect of four disaccharides alone or in combination on the lactoperoxidase (LP) derived from bovine milk during lyophilization. Sucrose, lactose, maltose, and trehalose at different concentrations (5-500 mM) were used to compare their protective effects on LP activity. The activity of lyophilized and native LP enzyme was evaluated using the procedure of Schindler with slight modifications. The antibacterial activity of the lyophilized enzyme against Pseudomonas aeroginosa, Escherichia coli, and Staphylococcus aureus was also investigated using the antimicrobial effectiveness test. Trehalose at concentration of 500 mM was the most effective cryoprotectant in protecting the enzyme activity. It preserved LP activity for 40 days, while the native enzyme lost its activity after 6 days. Combinations of disaccharides resulted in an increment in the stability of the enzyme, compared to the native enzyme. Combination of 200 mM trehalose and 200 mM sucrose were found most effective cryoprotectant in freeze-drying of LP. The lyophilized LP decreased the growth rate of Ps.aeroginosa, E.coli, and S.aureus between up to 30.8% in 106 cfu/ml and 53.3% in 105 cfu/ml. Antimicrobial efficacy of LP was more pronounced when 105 cfu/ml was used as compared to 106 cfu/ml. [ABSTRACT FROM AUTHOR]

Glibenclamide (GLIB) is a poorly soluble drug with formulation-dependent bioavailability. Therefore, we attempted in this study to improve GLIB dissolution rate by preparing drug solid dispersions by solvent evaporation (SE) and supercritical fluid solvent-antisolvent techniques (SCF-SAS). A D-optimal mixture design was used to investigate the effects of different ratios of HPMCE5 (50-100%), PEG6000 (0-40%), and Poloxamer407 (0-20%) on drug dissolution from different solid dispersion (SD) formulations prepared by SE. The ratios of carriers used in SCF-SAS method were HPMCE5 (fixed at 60%), PEG6000 (20-40%), and Poloxamer407 (0-20%). A constant drug: carrier weight ratio of 1:10 was used in all experiments. The SDs obtained were physically characterized and subjected to the dissolution study. The major GLIB bands in FTIR spectra were indicative of drug integrity. The reduced intensity and the fewer number of peaks observed in X-ray diffractograms (XRD) of GLIB formulations was the indicative of at least partial transformation of crystalline to amorphous GLIB. This change and/or dilution of drug in much higher amounts of carriers present caused disappearance of distinctive endothermic peaks in differential scanning calorimetry thermograms of GLIB formulations. The model generated according to the results of the Doptimal mixture design indicated that GLIB formulations comprising HPMC (50%-60%), PEG (34-40%), and poloxamer (6-10%) had enhanced dissolution performances. As compared to SE method, the SCF-SAS technique produced formulations of higher dissolution performances, likely due to the effects of solution and the supercritical CO2 (SC-CO2) on enhanced plasticization of polymers and thus increased diffusion of the drug into the polymer matrix. [ABSTRACT FROM AUTHOR]

Buccal mucoadhesive systems among novel drug delivery systems have attracted great attention in recent years due to their ability to adhere and remain on the oral mucosa and to release their drug content gradually. Buccal mucoadhesive films can improve the drug therapeutic effect by enhancement of drug absorption through oral mucosa increasing the drug bioavailability via reducing the hepatic first pass effect. The aim of the current study was to formulate the drug as buccal bioadhesive film, which releases the drug at sufficient concentration with a sustain manner reducing the frequency of the dosage form administration. One of the advantagees of this formulation is better patient compliances due to the ease of administration with no water to swallow the product. The mucoadhesive films of glibenclamide were prepared using hydroxypropyl methylcellulose (HPMC) K4M, K15M and Eudragit RL100 polymers and propylene glycol as plasticizer and co-solvent. Films were prepared using solvent casting method, and were evaluated with regard to drug content, thickness, weight variations, swelling index, tensile strength, ex vivo adhesion force and percentage of in vitro drug release. Films with high concentrations of HPMC K4M and K15M did not have favorable appearance and uniformity. The formulations prepared from Eudragit were transparent, uniform, flexible, and without bubble. The highest and the lowest percentages of swelling were observed for the films containing HPMC K15M and Eudragit RL100, respectively. Films made of HPMC K15M had adhesion force higher than those containing Eudragit RL100. Formulations with Eudragit RL100 showed the highest mean dissolution time (MDT). Drug release kinetics of all formulations followed Higuchi's model and the mechanism of diffusion was considered non-Fickian type. It was concluded that formulations containing Eudragit RL100 were more favorable than others with regard to uniformity, flexibility, rate and percentage of drug release. [ABSTRACT FROM AUTHOR]

The article looks at several cases of tick-borne encephalitis virus (TBEV) among U.S. travelers based on the review of the U.S. Centers for Disease Control and Prevention (CDC). The reports had TBEV or Powassan virus (POWV) immunoglobulin M (IgM) antibodies in serum and were regarded as acute TBE cases by plaque-reduction neutralization tests against both viruses. It notes that four patients who went to Europe or Russia who acquired biphasic illnesses were able to recover.

Gliclazide is a second generation of hypoglycemic sulfonylurea and acts selectively on pancreatic β cell to control diabetes mellitus. The objective of this study was to produce a controlled release system of gliclazide using chitosan beads. Chitosan beads were produced by dispersion technique using tripolyphosphate (TPP) as gelating agent. The effects of process variables including chitosan molecular weight, concentration of chitosan and TPP, pH of TPP, and cross-linking time after addition of chitosan were evaluated by Taguchi design on the rate of drug release, mean release time (MRT), release efficiency (RE8%), and particle size of the beads. The blood glucose lowering effect of the beads was studied in normal and streptozotocin-diabetic rats. The optimized formulation CL2T5P2t10 with about 31% drug loading, 2.4 h MRT, and 69.16% RE8% decreased blood glucose level in normal rats for 24 h compared to pure powder of gliclazide that lasted for just 10 h. [ABSTRACT FROM AUTHOR]

Two electrogenic H[sup +]-pumps, the vacuolar type H[sup +]-ATPase (V-ATPase) and the vacuolar pyrophosphatase, coexist at membranes of the secretory pathway of plants. The V-ATPase is the dominant H[sup +]-pump at endomembranes of most plant cells, both in terms of protein amount and, frequently, also in activity. The V-ATPase is indispensable for plant growth under normal conditions due to its role in energizing secondary transport, maintenance of solute homeostasis and, possibly, in facilitating vesicle fusion. Under stress conditions such as salinity, drought, cold, acid stress, anoxia, and excess heavy metals in the soil, survival of the cells depends strongly on maintaining or adjusting the activity of the V-ATPase. Regulation of gene expression and activity are involved in adapting the V-ATPase on long- and short-term bases. The mechanisms known to regulate the V-ATPase are summarized in this paper with an emphasis on their implications for growth and development under stress. [ABSTRACT FROM AUTHOR]

Cites a case report on West Nile virus infections in organ transplant recipients. Cause of death of the organ donor; State of the liver recipient on the twenty-third day of the transplantation; Result of the physical examination on the lung recipient seventeen days after transplantation; Policy of the U.S. for organ-donor screening.