Mixed Berry Juice and Cellulose Fiber Have Differential Effects on Peripheral Blood Mononuclear Cell Respiration in Overweight Adults.

Berries and other anthocyanin-rich foods have demonstrated anti-obesity effects in rodents and humans. However, the bioactive components of these foods and their mechanisms of action are unclear. We conducted an intervention study with overweight and obese adults to isolate the effects of different berry components on bioenergetics. Subjects consumed whole mixed berries (high anthocyanin, high fiber), pressed berry juice (high anthocyanin, low fiber), berry-flavored gelatin (low anthocyanin, low fiber), or fiber-enriched gelatin (low anthocyanin, high fiber) for one week prior to a meal challenge with the same treatment food as the pre-feed period. Peripheral blood mononuclear cells were collected 2 h after the meal challenge, and cellular respiration was assessed via high-resolution respirometry. The high-anthocyanin, low-fiber treatment (berry juice) and the low-anthocyanin, high-fiber treatment (fiber-enriched gelatin) had opposite effects on cellular respiration. In the fasted state, berry juice resulted in the highest oxygen-consumption rate (OCR), while fiber-enriched gelatin resulted in the highest OCR in the fed state. Differences were observed in multiple respiration states (basal, state 3, state 4, uncoupled), with the greatest differences being between the pressed berry juice and the fiber-enriched gelatin. Different components of berries, specifically anthocyanins/flavonoids and fiber, appear to have differential effects on cellular respiration.

Antimicrobial resistance and pathogenicity of Escherichia coli isolated from common dairy products in the Lebanon.

In a recent study, bacteria have been isolated from popular Lebanese dairy products, which had been collected in the Beqaa Valley, in north-eastern Lebanon. The foods investigated were two cheeses (shankleesh and baladi) and a dried fermented mixture of yogurt and wheat grains (kishk). Bacterial colonies on McConkey and sorbitol-McConkey agar that showed the morphology of Escherichia coli were biochemically tested and then classified, using PCR-based assays, into the various strains of pathogenic and non-pathogenic E. coli. Some of the confirmed E. coli isolates were proven to be pathogenic, including two identified as E. coli O157:H7. When the pathogenic isolates were tested for their susceptibility to 10 different antibiotics (all commonly used, by clinicians and veterinarians, for the treatment of infections with Gram-negative bacteria), each tested isolate was found to be highly resistant to at least one antibiotic. It therefore appears that, in Lebanon, some popular dairy products pose a public-health hazard, acting as vehicles for the transmission of drug-resistant pathogens.

Inhaled large porous particles of capreomycin for treatment of tuberculosis in a guinea pig model.

Capreomycin is used for the treatment of multidrug-resistant tuberculosis (MDR-TB), but it is limited therapeutically by its severe side effects. The objectives of the present studies were (i) to design low-density porous capreomycin sulfate particles for efficient pulmonary delivery to improve local and systemic drug bioavailability and capacity to reduce the bacillary load in the lungs in a manner similar to that achieved with intramuscular injections; (ii) to determine pharmacokinetic parameters after pulmonary administration of these capreomycin particles; and (iii) to evaluate the efficacy of these particles in treating animals in a small-aerosol-inoculum guinea pig model of TB. Capreomycin particles were manufactured by spray drying and characterized in terms of size and drug content. Pharmacokinetic parameters were determined by noncompartmental methods with healthy guinea pigs after administration of capreomycin particles by insufflation. The efficacy of the particles was evaluated by histopathological analysis and in terms of wet organ weight and bacterial burden in TB-infected animals. Lungs of animals receiving a 14.5-mg/kg dose of capreomycin particles showed significantly lower wet weights and smaller bacterial burdens than those of animals receiving any other treatment. These results were supported by histopathological analysis. The feasibility of inhaling capreomycin in a novel powder form, with the ultimate objective of the treatment of MDR-TB, is demonstrated by pharmacokinetic and pharmacodynamic studies with guinea pigs. If applied to humans with MDR-TB, such a therapeutic approach might simplify drug delivery by eliminating injections and might reduce adverse effects through lowering the dose.

Single dose pharmacokinetics and bioavailability of nevirapine in healthy volunteers.

The results of two randomized, single-dose, crossover bioavailability studies are presented which describe the pharmacokinetics and oral bioavailability of nevirapine, a novel nonnucleoside antiretroviral drug. In the first study 12 healthy male volunteers received nevirapine 15 mg via short-term i.v. infusion or orally as a 50 mg tablet or reference solution (50 mg/200 mL). Following the i.v. dose, nevirapine had a low systemic clearance (Mean +/- S.D., Cl = 1.4 +/- 0.3 L/h) and a prolonged elimination phase (t(1/2beta) = 52.8 +/- 14.8 h; MRT = 81.4 +/- 22.4 h). Nevirapine absolute bioavailability was 93 +/- 9% and 91 +/- 8% for the tablet and oral solution, respectively. In the second study, 24 healthy male volunteers were administered nevirapine as a 200 mg production-line tablet or oral reference solution (200 mg/200 mL). There was no significant difference in bioavailability between the tablet and reference solution. Overall, comparison of the pharmacokinetic parameters between the 50 and 200 mg doses indicates that nevirapine is well absorbed at clinically relevant doses. The absorption profiles using deconvolution revealed no evidence of differential enzyme induction between the two doses or routes of administration following a single dose.

Solubilization and in vitro spermicidal assessment of nonoxynol-9 and selected fractions using rabbit spermatozoa.

Selected oligomers representing the high, medium, and low molecular weight fractions of the spermicidal agent Nonoxynol-9 (N-9) were separated by HPLC. Nonoxynol-9 and the isolated fractions were formulated with polyvinylpyrrolidone (PVP) in order to increase their water solubility, particularly that of the insoluble low molecular weight fraction. The in vitro spermicidal activity of three molecular weight fractions were compared to that of N-9, using rabbit spermatozoa, at equimolar concentrations. Nonoxynol-9/PVP was far more effective in immobilizing the sperm than either N-9 alone or the separate fractions. The relative spermicidal activity of the oligomers was of the order middle molecular weight greater than high molecular weight greater than low molecular weight.

Development of an HPLC assay for the analysis of tetrafluoroputrescine--a putrescine analog.

A simple reverse-phase liquid chromatographic system with ultraviolet detection at 254 nm for tetrafluoroputrescine (TFP), a putrescine analog, is described. The assay involves precolumn derivatization of TFP with dansyl chloride at pH 6.8-7.5 at 60 degrees C, followed by separation from putrescine (PUT) and quantitation. The derivatization procedure was adapted for the simultaneous analysis of TFP and PUT in whole blood components. Also, preliminary studies on protein binding of TFP are reported.

Detection of tetrafluoroputrescine in RBCs by fluorine-19 nuclear magnetic resonance spectroscopy.

Fluorine-19 nuclear magnetic resonance spectroscopy is used to detect the in vitro uptake of tetrafluoroputrescine, a novel putrescine analogue, in red blood cells.