Desensitizing and non-desensitizing subtypes of alpha-bungarotoxin-sensitive nicotinic acetylcholine receptors in cockroach neurons

Two alpha-bungarotoxin-sensitive nicotinic receptor subtypes in cockroach neurons are identified as desensitizing (nAChD), selectively inhibitable with 100 nM imidacloprid, and non-desensitizing (nAChN), selectively inhibitable with 100 pM methyllycaconitine. Although the desensitization rate of nAChD receptors is highly variable, pharmacology is largely independent of desensitization rate. Because desensitized states tightly bind agonists, nAChD receptors are potently inhibited by neonicotinoids and specifically measured in radiolabeled imidacloprid binding assays. However, they are not usually detected in binding assays with radiolabeled alpha-bungarotoxin, which has a Kd for the resting state of 21 nM, but binds poorly to desensitized states often present in binding assays. In contrast, nAChN receptors are specifically measured in binding assays with radiolabeled alpha-bungarotoxin, which binds them with a Kd of 1.3 nM. nAChN receptors are activated by neonicotinoids at micromolar concentrations, and allosterically by spinosyn A, with an EC50 of 27 nM. Spinosyn A weakly antagonizes nAChD receptors -23% at 10 microM. The roles of the two nAChR subtypes in insecticide poisoning are discussed.     

Carotenoid-based plumage coloration of male greenfinches reflects health and immunocompetence

Hypotheses of parasite-mediated sexual selection (PMSS) propose that elaborate male ornaments have evolved due to female preferences. Females would benefit from mating with more ornamental males if males' ornamentation signals their health status and ability to provide parasite resistance genes for the offspring. Carotenoid-based plumage coloration of birds has been hypothesised to honestly reflect an individual's health status due to trade-off in allocation of carotenoids between maintenance and signalling functions. The prediction of this hypothesis, namely that individuals with brighter plumage are able to mount stronger immune responses against novel antigens and reveal generally better health state, was tested in captive male greenfinches (Carduelis chloris). Greenfinches with brighter yellow breast feathers showed stronger humoral immune response against novel antigen (SRBC) while no relationship between plumage coloration and an estimate of cell-mediated immune responsiveness (PHA response) was detected. Elaborately ornamental individuals had better general health state as indicated by the negative correlations between plumage brightness and heterophil haemoconcentration. Consistent with the concept of PMSS, these results suggest that carotenoid-based plumage coloration in greenfinches honestly signals immunocompetence and health status.     

Fat soluble antioxidants in brood-rearing great tits Parus major: relations to health and appearance

The concept of parasite-mediated sexual selection assumes that females may improve offspring fitness by selecting mates on the basis of sexual ornaments that honestly reveal the health state of a partner. Expression of such signals may be particularly sensitive to oxidative damage caused by excess production of oxidative metabolites and free radicals. To control and neutralise free radicals, animals rely heavily on dietary fat-soluble antioxidants such as vitamin E and A, and carotenoids. However, the organism's need for free radical scavenging may interfere with the opposite need to generate oxidative stress for fighting parasitic infections. We investigated plasma concentrations of carotenoids and vitamin A and E in brood-rearing great tits Parus major in relation to carotenoid-based plumage coloration, sex, habitat, leukocyte hemoconcentrations and infection status with Haemoproteus blood parasites. Rural great tits differed from urban ones and males from females with respect to the hue of the yellow ventral feathers. However, plasma antioxidant concentrations were not related to sex, habitat or plumage coloration. Plasma carotenoid concentration correlated positively with indices of immune system activation as measured by blood counts of lymphocytes and eosinophils. Birds with gametocytes of Haemoproteus in their blood had higher plasma concentrations of carotenoids and vitamin E than unparasitized individuals. These results are consistent with the idea that maintenance of high blood antioxidant levels might conflict with individual needs to rely on oxidative stress for fighting infections.     

Dahlia spectabilis (Asteraceae, Coreopsideae), a new species from San Luis Potosí, Mexico

Dahlia spectabilis (Asteraceae, Coreopsideae), a new species from San Luis Potosí, Mexico, is described and illustrated. The plant is distinguished by its large habit, big flowering heads, and overall lack of trichomes. It occurs within the natural range for the genus and is known from only one location where it is under heavy grazing pressure.

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Resumen   Dahlia spectabilis (Asteraceae, Coreopsideae), una especie nueva del estado de San Luis Potosí, México, es descrita e ilustrada. Se distingue por su hábito más grande, su grandes inflorescencias y la falta de tricomas. Ocuriendo dento del rango natural del género, conocida solo por un poblacón, la cual está sufriendo por presión de ganado.

     

PipeCraft: Flexible open‐source toolkit for bioinformatics analysis of custom high‐throughput amplicon sequencing data

High‐throughput sequencing methods have become a routine analysis tool in environmental sciences as well as in public and private sector. These methods provide vast amount of data, which need to be analysed in several steps. Although the bioinformatics may be applied using several public tools, many analytical pipelines allow too few options for the optimal analysis for more complicated or customized designs. Here, we introduce PipeCraft, a flexible and handy bioinformatics pipeline with a user‐friendly graphical interface that links several public tools for analysing amplicon sequencing data. Users are able to customize the pipeline by selecting the most suitable tools and options to process raw sequences from Illumina, Pacific Biosciences, Ion Torrent and Roche 454 sequencing platforms. We described the design and options of PipeCraft and evaluated its performance by analysing the data sets from three different sequencing platforms. We demonstrated that PipeCraft is able to process large data sets within 24 hr. The graphical user interface and the automated links between various bioinformatics tools enable easy customization of the workflow. All analytical steps and options are recorded in log files and are easily traceable.     

Physical activity and blood pressure in normotensive young women

Blood pressure and heart rate were measured in 22 physically active normotensive women, 20 +/- 1.7 years old (mean +/- SD) and in 25 physically non-active normotensive women 20.9 +/- 1.7 years old in supine, sitting and standing positions. Diastolic and mean blood pressures were found to be significantly lower in active women than non-active women. A significant negative correlation was found between maximal oxygen consumption and blood pressure, and it is suggested that aerobic physical activity could be used as non-pharmacological therapy in cases of moderate and borderline hypertension in young women.     

Physical Activity and Bone Mineral Accrual in Boys with Different Body Mass Parameters during Puberty: A Longitudinal Study

The aim of our longitudinal study was to investigate the relationships between physical activity and bone mass in boys with different body mass status during the years surrounding pubertal growth spurt. Two hundred and six boys entering puberty took part in this study. The subjects were divided into underweight (), normal weight (), overweight () and obese () groups at baseline according to age related categories. Whole-body DXA scans were performed at baseline, after 12 and 24 months to assess body composition (lean body mass, fat mass), and total body (TB), lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD) parameters. Physical activity was measured by 7- day accelerometry. For longitudinal analysis, multilevel fixed effects regression models were constructed. Biological age, height and lean body mass had an effect for explanation of TB BMD, FN BMD and LS BMD. Moderate to vigorous physical activity (MVPA), vigorous physical activity (VPA) and sedentary time (SED) had the significant effect only on FN BMD. Being an underweight boy at the baseline indicated greater chance (p<0.01) to have lower TB BMD in the future (2 years at follow up) development, compared to normal weight (estimates = −0.038), overweight (estimates = −0.061) and obese boys (estimates = −0.106).     

Physical and Social Environment Are Associated to Leisure Time Physical Activity in Adults of a Brazilian City: A Cross-Sectional Study

The physical activity practice is highlighted as a strategy to health promotion and to avoid chronic diseases. In addition to individual factors, environmental characteristics in which people live, may offer opportunities or barriers in adopting healthy habits and this is related to the physical activity (PA) practice among individuals. The aim of this study is to investigate the associations between neighborhood environment and leisure-time physical activity in adults. This is a cross-sectional study, developed using the database of Surveillance System for Risk and Protective Factors for Chronic Diseases by Telephone Survey (VIGITEL 2008/2010) of Belo Horizonte, Brazil. Individuals with the habit of practicing PA for at least 150 minutes of moderate-intensity PA or at least 75 minutes of vigorous-intensity PA throughout the week in leisure time were classified as active in leisure time. To characterize the built and social environment we used georeferenced data of public and private places for physical activity, population density, residential density, homicide rate and total income of the coverage area of the basic health units. The covered area of the basic health units was used as context unit. For data analysis, we used multilevel logistic regression. The study included 5779 adults, 58.77% female. There was variability of physical activity in leisure time between area covered by the basic health units (Median Odds ratio = 1.30). After adjusting for individual characteristics, the increase of density of private places for physical activity (Odds ratios—OR = 1.31; 95% confidence interval—95% CI: 1.15 to 1.48) and the smaller homicide rate (OR = 0.82; IC95%: 0.70 to 0.96) in the neighborhood increased physical activity in leisure time. The evidence of this study shows that neighborhood environment may influence the physical activity practice in leisure time and should be considered in future interventions and health promotion strategies.