Polyamine biosynthesis in rabbit perfused heart under various degrees of oxygen tension

Ornithine decarboxylase and S-adenosylmethionine decarboxylase activities increase in hypoxic perfused rabbit heart (more with less severe hypoxia). Anoxic perfusion causes a decrease in the former activity and no effect in the latter. Changes in polyamine specific radioactivity are consistent with those of the the two enzymes, except for the enhancement at 60 minutes of anoxia.     

Correction to: Amycolatopsis pittospori sp. nov., an endophytic actinobacterium isolated from native apricot tree and genome mining revealed the biosynthesis potential as antibiotic producer and plant growth promoter

Antonie van Leeuwenhoek -     

Expression and activity of cyclooxygenase isoforms in skeletal muscles and myocardium of humans and rodents.

Conflicting data have been reported on cyclooxygenase (COX)-1 and COX-2 expression and activity in striated muscles, including skeletal muscles and myocardium, in particular it is still unclear whether muscle cells are able to produce prostaglandins (PGs). We characterized the expression and enzymatic activity of COX-1 and COX-2 in the skeletal muscles and in the myocardium of mice, rats and humans. By RT-PCR, COX-1 and COX-2 mRNAs were observed in homogenates of mouse and rat hearts, and in different types of skeletal muscles from all different species. By Western blotting, COX-1 and -2 proteins were detected in skeletal muscles and hearts from rodents, as well as in skeletal muscles from humans. Immunoperoxidase stains showed that COX-1 and -2 were diffusely expressed in the myocytes of different muscles and in the myocardiocytes from all different species. In the presence of arachidonic acid, which is the COX enzymatic substrate, isolated skeletal muscle and heart samples from rodents released predominantly PGE(2). The biosynthesis of PGE(2) was reduced between 50 and 80% (P < 0.05 vs. vehicle) in the presence of either COX-1- or COX-2-selective blockers, demonstrating that both isoforms are enzymatically active. Exogenous PGE(2) added to isolated skeletal muscle preparations from rodents did not affect contraction, whereas it significantly fastened relaxation of a slow type muscle, such as soleus. In conclusion, COX-1 and COX-2 are expressed and enzymatically active in myocytes of skeletal muscles and hearts of rodents and humans. PGE(2) appears to be the main product of COX activity in striated muscles.     

Screening and secretomic analysis of enthomopatogenic Beauveria bassiana isolates in response to cowpea weevil (Callosobruchus maculatus) exoskeleton

The production of cowpea (Vigna unguiculata), an important self-sustained crop in Latin America and Africa, is severely affected by damage by the cowpea weevil Callosobruchus maculatus. The presence of a single larva in stored seeds can lead to losses of almost 40%. Control of C. maculatus currently relies on the inefficient use of chemical insecticides and post-harvest treatments. The use of entomopathogenic fungus became a reliable alternative for coleopteran pest control and has been extensively investigated. Among them, Beauveria bassiana and Metarhizium anisopliae were widely evaluated in order to measure their virulence toward many insects. In this report, we evaluated the insecticidal activity of ten strains of B. bassiana and the most lethal fungi strains were analyzed for proteinaceous secretions by two dimensional electrophoresis and for enzyme activities, including chitinolytic, proteolytic and alpha-amylolytic activities. This study could, in the near future, help to establish novel biotechnological tools to use for cowpea weevil control.     

Oxidized transthyretin in amniotic fluid as an early marker of preeclampsia

Preeclampsia is a pregnancy-specific hypertensive syndrome and a major cause of maternal and fetal morbidity and mortality. At the present time, no reliable screening tests to identify women at risk are available. We have compared the amniotic fluids (AF) proteomic maps of five preeclamptic patients with those of five controls. The analysis was carried out by two-dimensional electrophoresis followed by peptide mapping and tandem mass spectrometric analysis. Besides the implementation of the previously published AF proteomic maps, our results show that transthyretin (TTR), the protein responsible for transporting both the thyroid hormone tyroxine and the retinol binding protein, is present in the AF of both preeclamptic and control women as a mixture of dimeric and post-translationally modified monomeric forms. Although the nature of these forms is similar in both groups, the preeclamptic women showed a significant increase in the amount of monomeric proteins with respect to the control group. Since the TTR monomeric forms are the results of different oxidizing reactions, we hypothesize that the higher oxidative stress in preeclampsia is the major destabilizing factor of the TTR functional dimeric form in the preeclamptic women.     

Community engagement: leadership tool for catastrophic health events

Disasters and epidemics are immense and shocking disturbances that require the judgments and efforts of large numbers of people, not simply those who serve in an official capacity. This article reviews the Working Group on Community Engagement in Health Emergency Planning's recommendations to government decision makers on why and how to catalyze the civic infrastructure for an extreme health event. Community engagement--defined here as structured dialogue, joint problem solving, and collaborative action among formal authorities, citizens at-large, and local opinion leaders around a pressing public matter--can augment officials' abilities to govern in a crisis, improve application of communally held resources in a disaster or epidemic, and mitigate community wide losses. The case of limited medical options in an influenza pandemic serves to demonstrate the civic infrastructure's preparedness, response, and recovery capabilities and to illustrate how community engagement can improve pandemic contingency planning.     

Stereoselective determination of vigabatrin enantiomers in human plasma by high performance liquid chromatography using UV detection

A rapid and simple high-performance liquid chromatographic method for the determination of the R-(-)- and S-(+)-enantiomers of the antiepileptic drug vigabatrin in human plasma is described. After adding the internal standard (1-aminomethyl-cycloheptyl-acetic acid), plasma samples (200 microL) are deproteinized with acetonitrile and the supernatant is derivatized with 2,4,6 trinitrobenzene sulfonic acid (TNBSA). Separation is achieved on a reversed-phase cellulose-based chiral column (Chiralcel-ODR, 250 mm x 4.6 mm i.d.) using 0.05 M potassium hexafluorophosphate (pH 4.5)/acetonitrile/ethanol (50:40:10 vol/vol/vol) as mobile phase at a flow-rate of 0.9 mL/min. Chromatographic selectivity is improved by concentrating the derivatives on High Performance Extraction Disk Cartridges prior to injection. Detection is at 340 nm. Calibration curves are linear (r(2)> or =0.999) over the range of 0.5-40 microg/mL for each enantiomer, with a limit of quantification of 0.5 microg/mL for both analytes. The assay is suitable for therapeutic drug monitoring and for single-dose pharmacokinetic studies in man.