Androgens augment renal vascular responses to ANG II in New Zealand genetically hypertensive rats

Males develop higher blood pressure than do females. This study tested the hypothesis that androgens enhance responsiveness to ANG II during the development of hypertension in New Zealand genetically hypertensive (NZGH) rats. Male NZGH rats were obtained at 5 wk of age and subjected to sham operation (Sham) or castration (Cas) then studied at three age groups: 6-7, 11-12, and 16-17 wk. Mean arterial blood pressure (MAP), heart rate (HR), and renal blood flow (RBF) measurements were recorded under Inactin anesthesia. These variables were measured after enalapril (1 mg/kg) treatment and during intravenous ANG II infusion (20, 40, and 80 ng/kg/min). Plasma testosterone was measured by ELISA. Angiotensin type 1 (AT1) receptor expression was assessed by Western blot analysis and RT-PCR. ANG II-induced MAP responses were significantly attenuated in Cas NZGH rats. At the highest ANG II dose, MAP increased by 40+/-4% in Sham vs. 22+/-1% in Cas NZGH rats of 16-17 wk of age. Similarly, renal vascular resistance (RVR) responses to ANG II were reduced by castration (209+/-20% in Sham vs. 168+/-10% in Cas NZGH rats at 16-17 wk of age). Castration also reduced MAP recorded in conscious NZGH rats of this age group. Testosterone replacement restored baseline MAP and the pressor and RVR responses to ANG II. Castration reduced testosterone concentrations markedly. Testosterone treatment restored these concentrations. Neither castration nor castration+testosterone treatment affected AT1 receptor mRNA or protein expression. Collectively, these data suggest that androgens modulate renal and systemic vascular responsiveness to ANG II, which may contribute to androgen-induced facilitation of NZGH rat hypertension.     

Biodegradation of diesel/biodiesel blends by a consortium of hydrocarbon degraders: effect of the type of blend and the addition of biosurfactants

Biodegradation experiments for diesel/biodiesel blends in liquid cultures by-petroleum degrading microbial consortium showed that for low amendments of biodiesel (10%) the overall biodegradation efficiency of the mixture after seven days was lower than for petroleum diesel fuel. Preferential usage of methyl esters in the broad biodiesel concentration range and diminished biodegradation of petroleum hydrocarbons for 10% biodiesel blend was confirmed. Rhamnolipids improved biodegradation efficiency only for blends with low content of biodiesel. Emulsion formation experiments showed that biodiesel amendments significantly affected dispersion of fuel mixtures in water. The presence of rhamnolipids biosurfactant affected stability of such emulsions and altered cell surface properties of tested consortium.     

Conjugates of auxin and cytokinin

Plant growth and developmental processes as well as environmental responses require the action and cross talk of phytohormones including auxins and cytokinins. Active phytohormones are changed into multiple forms by acylation, esterification or glycosylation, for example. It seems that conjugated compounds could serve as pool of inactive phytohormones that can be converted to active forms by de-conjugation reactions. The concept of reversible conjugation of auxins and cytokinins suggests that under changeable environmental, developmental or physiological conditions these compounds can be a source of free hormones. Phytohormones metabolism may result in a loss of activity and decrease the size of the bioactive pool. All metabolic steps are in principle irreversible, except for some processes such as the formation of ester, glucoside and amide conjugates, where the free compound can be liberated by enzymatic hydrolysis. The role, chemistry, synthesis and hydrolysis of conjugated forms of two classes of plant hormones are discussed.     

Solid phase synthesis of peptides containing novel amino acids, substituted 3-benzimidazolealanines

A direct solid-phase synthesis of a series of substituted benzimidazole-containing peptides is described. The method involves on-resin formation of new amino acids containing benzimidazole derivatives in the side chain. The heterocycle conjugates were obtained by reaction between aldehydes and peptides containing β-(3,4-diaminophenyl)alanine residue, immobilized on a polymeric solid support.     

Use of the chromosomal co-location of the minor 5S and the major 28S rDNA as a cytogenetic marker within the genus Leuciscus (Pisces, Cyprinidae)

The chromosomes of three species from the genus Leuciscus (the ide L. idus, the European chub L. cephalus and the common dace L. leuciscus) were examined with the FISH technique for 5S and 28S rDNA probes. The analysis showed that among the three examined species, 5S rDNA signals were located on two large and four small subtelocentric chromosomes in L. leuciscus, on one large and five small subtelocentric chromosomes in L. idus, while in L. cephalus the probe signals were found on two metacentric chromosomes and one large and one small subtelocentric chromosome pairs. In all analysed species, the 28S rDNA probe signals were placed on only one chromosome pair, subtelocentric in the common dace and the European chub, and submetacentric in the ide. The three species differed in the number of sites in which both probe signals were present. In conclusion, the co-location of the 5S and 28S rDNA proved to be a useful cytogenetic marker among the studied fishes. Moreover, this marker could be adapted to other cyprinids.     

Assessment between pollen seasons in areas with different urbanization level related to local vegetation sources and differences in allergen exposure

Pollen data recorded by a single sampler in any given city often fail to reflect particular events occurring in surrounding areas. This is frequently overlooked when interpreting aerobiological results, and therefore pollen data obtained in urban areas may not necessarily be representative of the situation in more rural areas of the same city. Our purpose is to assess differences between allergenic pollen concentrations recorded in an urban area (Eskulap) and a rural/suburban (Morasko) of the same city from 2005 to 2007. Anova-Manova Scheffe, Spearman correlation and Mixed-design ANOVA whitin-subjects effects tests were applied. The results obtained have showed longer pollen seasons, earlier starts of flowering and later conclusion in the urban area. The participation of arboreal pollen in the pollen fall of both sites had enough significative similarities to determine that is linked to regional conditions, while differences in the atmospheric pollen content of herbaceous plants between sites should be due to local conditions.     

Molecular epidemiology of Candida albicans and Candida glabrata strains isolated from intensive care unit patients in Poland

Over the last decades, Candida spp have been responsible for an increasing number of infections, especially in patients requiring intensive care. Knowledge of local epidemiology and analysis of the spread of these pathogens is important in understanding and controlling their transmission. The aim of this study was to evaluate the genetic diversity of 31 Candida albicans and 17 Candida glabrata isolates recovered from intensive care unit patients from the tertiary hospital in Krakow between 2011-2012. The strains were typed by random amplified polymorphic DNA (RAPD) polymerase chain reaction using five primers (CD16AS, HP1247, ERIC-2, OPE-3 and OPE-18). The results of the present investigation revealed a high degree of genetic diversity among the isolates. No clonal relationship was found among the C. albicans strains, whereas two C. glabrata isolates were identical. The source of Candida infection appeared to be mostly endogenous; however, the presence of two clonal C. glabrata strains suggested the possibility of cross-transmission of these pathogens. Our study confirmed the high discriminatory power of the RAPD technique in the molecular typing of Candida clinical isolates. This method may be applied to the evaluation of transmission routes of pathogenic fungi on a local level.     

Obesity-associated hyperleptinemia alters the gliovascular interface of the hypothalamus to promote hypertension

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Inhibitor analysis of angiotensin I-converting and kinin-degrading activities of bovine lung and testicular angiotensin-converting enzyme.

Inhibition of bovine lung and testicular angiotensin-converting enzyme (ACE) by some well-known ACE inhibitors (lisinopril, captopril, enalapril), new substances (Nalpha-carboxyalkyl dipeptides PP-09, PP-35, and PP-36), and phosphoramidon was investigated using Cbz-Phe-His-Leu and FA-Phe-Phe-Arg (C-terminal analogs of angiotensin I and bradykinin, respectively) as the substrates. The somatic (two domains) and testicular (single domain) isoenzymes demonstrated different kinetic parameters for hydrolysis of these substrates. All of the inhibitors were competitive inhibitors of both ACE isoforms, and the Ki values were substrate-independent. The relative potencies of the inhibitors for both enzymes were: lisinopril > captopril > PP-09 > enalapril > PP-36 > PP-35 > phosphoramidon. The inhibition efficiency of PP-09 was comparable with those of the well-known ACE inhibitors. Captopril was more effectively bound to the somatic ACE (Ki = 0.5 nM) than to the testicular isoform (Ki = 6.5 nM).     

Reduced expression of α-tubulin genes in Arabidopsis thaliana specifically affects root growth and morphology, root hair development and root gravitropism

Different alpha-tubulin cDNA sequences fused in an antisense orientation to a CaMV 35S promoter were introduced into Arabidopsis thaliana plants. Several independent transgenic lines that showed a moderate but clear reduction of alpha-tubulin gene expression (TUA6/AS lines) were obtained and phenotypically characterized. Although no apparent abnormalities were detected in the aerial parts of TUA6/AS plants, root development was severely affected. Cells in TUA6/AS root tips were found to contain aberrant microtubular structures, to expand abnormally and to be unable to undergo regular cell division. These cellular defects caused a dramatic radial expansion of the root tip and inhibited root elongation. In addition, TUA6/AS roots displayed ectopic formation of root hairs, root hair branching and a reduced ability to respond to gravitropic challenges. Our results contribute to an improved understanding of the different roles microtubules play during root development and demonstrate that reverse genetics is a powerful tool to analyze cytoskeletal functions during plant organogenesis.