Bat assemblage structure in two dry forests of Colombia: Composition, species richness, and relative abundance

We studied the composition, species richness, and relative abundance of bat assemblages in the Colombian dry forests of Chicamocha and Patía. In Chicamocha, 11 bats of the family Phyllostomidae were captured with mist-nets, corresponding to 85–100% of the potential phyllostomids species in the area. Two bats of the family Vespertilionidae were also captured in Chicamocha. In Patía, 12 species were captured with mist-nets, all Phyllostomidae, representing 72–100% of the estimated total number of species in the zone. Minor differences in number of species and composition were detected among sampling periods in Chicamocha. The most common species in this dry forest were Glossophaga longirostris and Sturnira lilium. In Patía, notable differences in the number of species and composition were observed among sampling periods, and the most common species were Artibeus jamaicensis, Carollia perspicillata and Phyllostomus discolor. Arid-zone dwelling bats were absent in Patía and we suggest that this absence may be associated with the isolation of Patía from other northern dry zones of Colombia since Quaternary times. There was also low abundance of bats in Patía, which appears to be related to human disturbance. The most abundant phyllostomid bat species in the two dry forests studied are those that include fruit and/or nectar-pollen from columnar cacti as an important proportion of their diets.     

Delineation of molecular species of a family of diacyltrehaloses from Mycobacterium fortuitum by mass spectrometry

Abstract Research regarding the accurate, quantitative degradation of novel poly-3-hydroxyalkanoates has been restricted by the absence of an appropriate monitoring technique. The calibration of a gas chromatograph to poly-3-hydroxyalkanoate reveals a linear relationship between the area under gas chromatograph tracings and polymer weight. With this new method, poly-3-hydroxyactanoate granules isolated from Pseudomonas oleovorans , which were incubated at 30°C in an alkaline buffer, exhibited a linear degradation rate. Degradation was inhibited by the presence of Triton X-100 and phenylmethylsulfonyl fluoride. The depolymerase was demonstrated to be associated with the polymer granule complex and most likely possessed serine residues at its active site.     

Salt stress increases ferredoxin-dependent glutamate synthase activity and protein level in the leaves of tomato

Ferredoxin-dependent glutamate synthase (EC 1.4.7.1) catalyzes an essential step in the pathway of glutamate biosynthesis. Exposing detached tomato ( Lycopersicon esculentum ) leaves for 6 h to 12 g l⁻¹ NaCl resulted in a significant two-fold increase in the activity of ferredoxin-dependent glutamate synthase extracted from the leaves. Western blot studies demonstrated that salt treatment also increased the ferredoxin-dependent glutamate synthase content of the leaves. A similar effect of salt on the concentration of this enzyme was found in the leaves of hydroponically-grown tomato plants. The induction of ferredoxin-dependent glutamate synthase under salt stress may provide the glutamate required for the proline synthesis which is a common response to salt stress.     

Fas-induced apoptosis in human malignant melanoma cell lines is associated with the activation of the p34(cdc2)-related PITSLRE protein kinases.

The Cdc2L locus encoding the PITSLRE protein kinases maps to chromosome band 1p36 and consists of two duplicated and tandemly linked genes. The purpose of the present study was to determine whether diminution of PITSLRE kinases leads to deregulation of apoptosis. The human melanoma cell lines A375 (Cdc2L wild-type alleles) and UACC 1227 (mutant Cdc2L alleles) were tested with agonist anti-Fas monoclonal antibody. We found that exposure of these cells to anti-Fas for 24, 48, or 72 h resulted in differential sensitivity to Fas-induced apoptosis. In A375, cell death started at 24-48 h post-treatment, and it was maximal by 72 h. Conversely, UACC 1227 cells were resistant to Fas-mediated apoptosis. Induction of PITSLRE histone H1 kinase activity was observed in A375 anti-Fas treated but not in UACC 1227 cells. Also, the PITSLRE protein kinase activity in A375 anti-Fas-treated cells preceded maximal levels of apoptosis. Finally, fluorescence confocal microscopy revealed a nuclear localization of PITSLRE proteins in normal melanocytes and A375 cells but a cytoplasmic localization in UACC 1227 cells. The differences in PITSLRE protein and cellular localization between A375 and UACC 1227 cells appear to account for the differences in sensitivity of the two cells lines to anti-Fas and staurosporine. These observations suggest that alterations in PITSLRE gene expression and protein localization may result in the loss of apoptotic signaling.     

Risk factors for tungiasis in Nigeria: identification of targets for effective intervention

Background

The parasitic skin disease tungiasis (caused by the flea Tunga penetrans) affects resource-poor communities in Latin America, the Caribbean and sub-Saharan Africa. Prevalences in endemic areas are high, and severe pathology occurs commonly. However, risk factors for infestation have never been assessed in Africa.

Methods and Findings

A cross-sectional study was conducted in Erekiti, a rural community in Lagos State (Nigeria), where tungiasis is endemic. Individuals were examined clinically for the presence of tungiasis, and a questionnaire was applied. Data from 643 individuals (86.6% of the target population) were analyzed; 252 (42.5%) were infested with T. penetrans. In the multivariate logistic regression analysis, presence of pigs on the compounds (adjusted odds ratio = 17.98; 95% confidence interval: 5.55–58.23), sand or clay floor inside houses (9.33; 5.06–17.19), and having the common resting place outside the house (7.14; 4.0–14.29) were the most important risk factors identified. The regular use of closed footwear (0.34; 0.18–0.62) and the use of insecticides indoors (0.2; 0.05–0.83) were protective against infestation. The population attributable fractions associated with tungiasis were: sand or clay floor inside the house (73.7%), resting usually outside the house (65.5%), no regular use of closed footwear (51.1%), and pigs on the compound (37.9%).

Conclusion

The presence of tungiasis in Erekiti is determined to an important extent by a limited number of modifiable variables. Effective and sustainable intervention measures addressing these factors need to be implemented in this and other West African communities with high disease burden.     

Características antropométricas,funcionales y de fuerza explosiva de mujeres mayores de 50 años físicamente activas de la ciudad de Bogotá, Colombia

Objective

To analyze the relationship between different test measuring explosive strength and functionality of active women participating in a leisure sport program in order to describe the caracteristics of health status and look for tools for diagnosing and monitoring degenerative process.

Methods

This study was conducted on 102 women physically active and without risk factors. Anthropometric, functional independence and explosive strength tests were applied.

Results

Mean age 60.08±5.35 years; body mass index: 26.81±3.91; percentage of fat: 52.45±4.75; percentage of muscle mass: 37.24±6.77; tests of functional independence: maximum speed (30 meters): 9.39±1.92 s; speed-agility (30 meters): 12.93±1.59 s, and dynamic balance (6 meters): 21.9±8.01 s. Explosive Strength (Bosco test): Squat Jump: 12.23±3.05 cm, Countermovement Jump: 13.18±3.04 cm and Countermovement Jump Arm swing: 14.80±4.01 cm.

Conclusion

The statistical relationships found between body composition, explosive strength and functionality tests, are important tools for diagnosing and monitoring, and could improve the intervention models on the elderly.     

Specificity of the trypanothione-dependent Leishmania major glyoxalase I: structure and biochemical comparison with the human enzyme

Trypanothione replaces glutathione in defence against cellular damage caused by oxidants, xenobiotics and methylglyoxal in the trypanosomatid parasites, which cause trypanosomiasis and leishmaniasis. In Leishmania major, the first step in methylglyoxal detoxification is performed by a trypanothione-dependent glyoxalase I (GLO1) containing a nickel cofactor; all other characterized eukaryotic glyoxalases use zinc. In kinetic studies L. major and human enzymes were active with methylglyoxal derivatives of several thiols, but showed opposite substrate selectivities: N1-glutathionylspermidine hemithioacetal is 40-fold better with L. major GLO1, whereas glutathione hemithioacetal is 300-fold better with human GLO1. Similarly, S-4-bromobenzylglutathionylspermidine is a 24-fold more potent linear competitive inhibitor of L. major than human GLO1 (Kis of 0.54 microM and 12.6 microM, respectively), whereas S-4-bromobenzylglutathione is >4000-fold more active against human than L. major GLO1 (Kis of 0.13 microM and >500 microM respectively). The crystal structure of L. major GLO1 reveals differences in active site architecture to both human GLO1 and the nickel-dependent Escherichia coli GLO1, including increased negative charge and hydrophobic character and truncation of a loop that may regulate catalysis in the human enzyme. These differences correlate with the differential binding of glutathione and trypanothione-based substrates, and thus offer a route to the rational design of L. major-specific GLO1 inhibitors.     

Changes in the protein profile of Quercus ilex leaves in response to drought stress and recovery

To characterize the molecular response of holm oak to drought stress and its capacity to recover 9-month-old Quercus ilex seedlings were subjected to three treatments for a 14-d period: (i) continuous watering to field capacity (control plants, W), (ii) no irrigation (drought treatment, D), and (iii) no irrigation for 7d followed by a watering period of 7d (recovery treatment, R). In drought plants, leaf water potential decreased from -0.72 (day 0) to -0.99MPa (day 7), and -1.50MPa (day 14). Shoot relative water content decreased from 49.3% (day 0) to 47.7% (day 7) and 40.8% (day 14). Photosystem II quantum yield decreased from 0.80 (day 0) to 0.72 (day 7) and 0.73 (day 14). Plants subjected to water withholding for 7d reached, after a 7-d rewatering period, values similar to those of continuously irrigated control plants. Changes in the leaf protein pattern in response to drought and recovery treatments were analyzed by using a proteomic approach. Twenty-three different spots were observed when comparing the two-dimensional electrophoresis profile of control to both drought and recovered plants. From these, 14 proteins were identified from tryptic peptides tandem mass spectra by using the new Paragon algorithm present in the ProteinPilot software. The proteins identified belong to the photosynthesis, carbohydrate and nitrogen metabolism, and stress-related protein functional categories.