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BackgroundHeart transplant (HT) recipients demonstrate limited exercise capacity compared to normal patients, very likely for multiple reasons. In this study we hypothesized that left atrial volume (LAV), which is known to predict exercise capacity in patients with various cardiac pathologies including heart failure and hypertrophic cardiomyopathy is associated with limited exercise capacity of HT recipients.MethodsWe analyzed 50 patients [age 57 ±2 (SEM), 12 females] who had a post-HT echocardiography and cardiopulmonary exercise test (CPX) within 9 weeks time at clinic follow up. The change in LAV (ΔLAV) was also computed as the difference in LAV from the preceding one-year to the study echocardiogram. Correlations among the measured parameters were assessed with a Pearson's correlation analysis.ResultsLAV (n = 50) and ΔLAV (n = 40) indexed to body surface area were 40.6 ± 11.5 ml·m-2 and 1.9 ± 8.5 ml·m-2·year-1, data are mean ± SD, respectively. Indexed LAV and ΔLAV were both significantly correlated with the ventilatory efficiency, assessed by the VE/VCO2 slope (r = 0.300, p = 0.038; r = 0.484, p = 0.002, respectively). LAV showed a significant correlation with peak oxygen consumption (r = -0.328, p = 0.020).ConclusionsAlthough our study is limited by a retrospective study design and relatively small number of patients, our findings suggest that enlarged LAV and increasing change in LAV is associated with the diminished exercise capacity in HT recipients and warrants further investigation to better elucidate this relationship.

Heavy metal-resistant bacteria can be efficient bioremediators of metals and may provide an alternative or additional method to conventional methods of metal removal. In this study, 10 bacterial isolates were isolated from soil samples of a sugar industry, located at Peshawar, Pakistan. Morphological, physiological, and biochemical characteristics of these isolates were observed. Sequence analysis (16S ribosomal RNA) revealed that isolated strains were closely related to the species belonging to the genera Pseudomonas, Arthrobacter, Exiguobacterium, Citrobacter, and Enterobacter Bacterial isolates were resistant with a minimum inhibitory concentration (500-900 ppm) to lead ion (Pb(2+)), (500-600 ppm) nickel ion (Ni(2+)), (500-800 ppm) copper ion (Cu(2+)), and (600-800 ppm) chromium ion (Cr(3+)) in solid media. Furthermore, biosorption of metals proved considerable removal of heavy metals by isolated metal-resistant strains. Pseudomonas sp. reduced 37% (Pb(2+)), 32% (Ni(2+)), 29% (Cu(2+)), and 32% (Cr(3+)) and was thus found to be most effective, whereas Enterobacter sp. reduced 19% (Pb(2+)), 7% (Ni(2+)), 14% (Cu(2+)), and 21% (Cr(3+)) and was found to be least effective. While average reduction of Pb(2+), Ni(2+), Cu(2+), and Cr(3+) by Citrobacter sp. was found to be 24%, 18%, 23%, and 27%, respectively, among recognized species. This study revealed that Pseudomonas sp. may provide a new microbial community that can be used for enhanced remediation of contaminated environment.

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Atmospheric particles (total suspended particles, TSPs) mass samples (288) were collected by high volume samplers at nine sampling locations in Faisalabad, Pakistan from May 2012 to April 2013. These TSP mass samples were subjected to gravimetric and quantitative chemical analyses for determining trace elements (Pb, Cd, Ni, Zn, Cu, Fe) using atomic absorption spectroscopy and water-soluble cations (Ca 2þ , Mg 2þ , Na þ and K þ , NH 4 þ ) and anions (Cl À , SO 4 2À , and NO 3 À ) by ion chromatography. The average TSP mass and elemental concentrations at all locations were found to be highest during the dry and lowest during the wet season. The crustal elements Ca, Fe, Mg, and Na were the largest contributors to TSP mass while elements of anthropogenic origin Pb, Cd, Ni, Cu, and Zn had relatively lower concentrations and also showing a high spatial variation. The concentration of TSP and elements exhibited the maxima at the sampling locations characterized by intensive industrial and vehicular activities. The wind rose analysis and the UNMIX model applied to chemical speciation data both identified the same three primary sources of TSP: power plant/refinery, brick kilns, and roadways. The normalized dot product was successfully used to quantify the similarity between different source profiles extracted from UNMIX model. The coupling of UNMIX with wind direction analysis complemented each other and provided a complete assessment of source contributions and locations.