942 research outputs found
Lack of maintenance of motorway fences works against their intended purpose with potential negative impacts on protected species
Linear infrastructure intrusions into natural ecosystems, such as motorways and high-speed railways, causes direct loss of habitat but also impacts fauna through collisions. Wildlife road mortality is well documented and extensive conservation legislation exists in many countries to minimise the negative impact of these infrastructures. However, although these measures are implemented because of legislation, these structures are often not adequately maintained. Here we present data on the functionality of perimeter fences along two motorways in Malaga province (southern Spain) erected to prevent collisions with the common chameleon (Chamaeleo chamaeleon). We sampled the fences along the 14 km of the two motorways included in the 17 1 × 1 km squares of the study area. Our results show that the reptile fence is permeable throughout at those points where the metal sheeting was absent and where the vegetation had overgrown around the fence, hence allowing chameleons to cross. Given our results, we conclude that this situation is likely to be similar in other regions of Spain and in other countries. This is because construction/concessionary companies do not consider the environmental impact of construction projects in the medium and long term, and environmental authorities do not ensure that companies comply with the legislation
The effects of age on associations between markers of HIV progression and markers of metabolic function including albumin, haemoglobin and lipid concentrations.
OBJECTIVES: We investigated whether age modified associations between markers of HIV progression, CD4 T lymphocyte count and HIV RNA viral load (VL), and the following markers of metabolic function: albumin, haemoglobin, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC).
METHODS: A retrospective analysis of data from the United Kingdom Collaborative HIV Cohort was carried out. Analyses were limited to antiretroviral-naïve subjects to focus on the impact of HIV disease itself. A total of 16670 subjects were included in the analysis. Multilevel linear regression models assessed associations between CD4 count/VL and each of the outcomes. Statistical tests for interactions assessed whether associations differed among age groups.
RESULTS: After adjustment for gender and ethnicity, there was evidence that lower CD4 count and higher VL were associated with lower TC, LDL-C, haemoglobin and albumin concentrations but higher triglyceride concentrations. Age modified associations between CD4 count and albumin (P 50 years, a 50 cells/μL lower CD4 count correlated with a 2.4 [95% confidence interval (CI) 1.7-3.0], 3.6 (95% CI 3.2-4.0) and 5.1 (95% CI 4.0-6.1) g/L lower haemoglobin concentration and a 0.09 (95% CI 0.07-0.11), 0.12 (95% CI 0.11-0.13) and 0.16 (95% CI 0.13-0.19) g/L lower albumin concentration, respectively.
CONCLUSIONS: We present evidence that age modifies associations between CD4 count and plasma albumin and haemoglobin levels. A given reduction in CD4 count was associated with a greater reduction in haemoglobin and albumin concentrations among older people living with HIV. These findings increase our understanding of how the metabolic impact of HIV is influenced by age
Incomplete reversibility of estimated glomerular filtration rate decline following tenofovir disoproxil fumarate exposure.
BACKGROUND: Tenofovir disoproxil fumarate (TDF) has been linked to renal impairment, but the extent to which this impairment is reversible is unclear. We aimed to investigate the reversibility of renal decline during TDF therapy.
METHODS: Cox proportional hazards models assessed factors associated with discontinuing TDF in those with an exposure duration of >6 months. In those who discontinued TDF therapy, linear piecewise regression models estimated glomerular filtration rate (eGFR) slopes before initiation of, during, and after discontinuation of TDF therapy. Factors associated with not achieving eGFR recovery 6 months after discontinuing TDF were assessed using multivariable logistic regression.
RESULTS: We observed declines in the eGFR during TDF exposure (mean slopes, -15.7 mL/minute/1.73 m(2)/year [95% confidence interval {CI}, -20.5 to -10.9] during the first 3 months and -3.1 mL/minute/1.73 m(2)/year [95% CI, -4.6 to -1.7] thereafter) and evidence of eGFR increases following discontinuation of TDF therapy (mean slopes, 12.5 mL/minute/1.73 m(2)/year [95% CI, 8.9-16.1] during the first 3 months and 0.8 mL/minute/1.73 m(2)/year [95% CI,.1-1.5] thereafter). Following TDF discontinuation, 38.6% of patients with a decline in the eGFR did not experience recovery. A higher eGFR at baseline, a lower eGFR after discontinuation of TDF therapy, and more-prolonged exposure to TDF were associated with an increased risk of incomplete recovery 6 months after discontinuation of TDF therapy.
CONCLUSIONS: This study shows that a decline in the eGFR during TDF therapy was not fully reversible in one third of patients and suggests that prolonged TDF exposure at a low eGFR should be avoided
Improved kidney function in patients who switch their protease inhibitor from atazanavir or lopinavir to darunavir
OBJECTIVE: Atazanavir (ATV) and lopinavir (LPV) have been associated with kidney
disease progression in HIV positive patients, with no data reported for darunavir (DRV).
We examined kidney function in patients who switched their protease inhibitor from
ATV or LPV to DRV.
DESIGN: Cohort study.
METHODS: Data were from the UK CHIC study. We compared pre and post switch
estimated glomerular filtration rate (eGFR) slopes (expressed in ml/min per 1.73 m2 per
year) in all switchers and those with rapid eGFR decline (>5 ml/min per 1.73 m2 per
year) on ATV or LPV. Mixed-effects models were adjusted for age, gender, ethnicity,
eGFR at switch and time updated CD4þ cell count, HIV RNA and cumulative tenofovir
(tenofovir disoproxil fumarate) exposure.
RESULTS: Data from 1430 patients were included. At the time of switching to DRV,
median age was 45 years, 79% were men, 76% had an undetectable viral load, and
median eGFR was 93 ml/min per 1.73 m2
. Adjusted mean (95% confidence interval) pre
and post switch eGFR slopes were 0.84 (1.31, 0.36) and 1.23 (0.80, 1.66) for ATV
(P < 0.001), and 0.57 (1.09, 0.05) and 0.62 (0.28, 0.96) for LPV (P < 0.001). Stable
or improved renal function was observed in patients with rapid eGFR decline on ATV or
LPV who switched to DRV [15.27 (19.35, 11.19) and 3.72 (1.78, 5.66), P < 0.001
for ATV, 11.93 (14.60, 9.26) and 0.87 (0.54, 2.27), P < 0.001 for LPV]. Similar
results were obtained if participants who discontinued tenofovir disoproxil fumarate at
the time of switch were excluded.
CONCLUSIONS: We report improved kidney function in patients who switched from ATV
or LPV to DRV, suggesting that DRV may have a more favourable renal safety profile
Geo-environmental mapping using physiographic analysis: constraints on the evaluation of land instability and groundwater pollution hazards in the Metropolitan District of Campinas, Brazil
Geo-environmental terrain assessments and territorial zoning are useful tools for the formulation and implementation of environmental management instruments (including policy-making, planning, and enforcement of statutory regulations). They usually involve a set of procedures and techniques for delimitation, characterisation and classification of terrain units. However, terrain assessments and zoning exercises are often costly and time-consuming, particularly when encompassing large areas, which in many cases prevent local agencies in developing countries from properly benefiting from such assessments. In the present paper, a low-cost technique based on the analysis of texture of satellite imagery was used for delimitation of terrain units. The delimited units were further analysed in two test areas situated in Southeast Brazil to provide estimates of land instability and the vulnerability of groundwater to pollution hazards. The implementation incorporated procedures for inferring the influences and potential implications of tectonic fractures and other discontinuities on ground behaviour and local groundwater flow. Terrain attributes such as degree of fracturing, bedrock lithology and weathered materials were explored as indicators of ground properties. The paper also discusses constraints on- and limitations of- the approaches taken
Using small molecules to facilitate exchange of bicarbonate and chloride anions across liposomal membranes
Bicarbonate is involved in a wide range of biological processes, which include respiration, regulation of intracellular pH and fertilization. In this study we use a combination of NMR spectroscopy and ion-selective electrode techniques to show that the natural product prodigiosin, a tripyrrolic molecule produced by microorganisms such as Streptomyces and Serratia, facilitates chloride/bicarbonate exchange (antiport) across liposomal membranes. Higher concentrations of simple synthetic molecules based on a 4,6-dihydroxyisophthalamide core are also shown to facilitate this antiport process. Although it is well known that proteins regulate Cl-/HCO3- exchange in cells, these results suggest that small molecules may also be able to regulate the concentration of these anions in biological systems
Nu?cleo de conservac?a?o de recursos gene?ticos animais da Amazo?nia oriental (Bagam) / Nucleus for the conservation of animal genetic resources of the eastern Amazon (Bagam)
O Brasil possui rica biodiversidade de animais, nativos e exóticos, sendo importante o estabelecimento de programas de conservação de recursos genéticos animais, especificamente para aquelas raças e/ou grupos genéticos ameaçados. Na Amazônia Oriental animais com finalidade zootécnica como os búfalos da raça Carabao e do tipo Baio, assim como o cavalo Marajoara e o mini cavalo Puruca, vêm sofrendo graves presso?es de acasalamentos e cruzamentos desordenados, colocando em grande risco de descaracterização e de desaparecimento das pequenas populações. Do mesmo modo os animais de fauna que possuem aptidão zootécnica estão submetidos a grande pressão de captura como o Muçuã, uma pequena tartaruga da Amazônia, endêmica da ilha de Marajó, pois fazem parte da cadeia alimentar das comunidades tradicionais e do mercado gourmet, tendo em vista ser um apreciado prato regional. Diante de tudo isso o trabalho de conservação objetiva o estudo da biologia dos animais, além de acompanhar as ações desses grupos genéticos no Banco de Germoplasma Animal da Amazo?nia Oriental (BAGAM), visando conter essas ameaças, com ênfase nos estudos de sua biologia e comportamento produtivo como, também, na coleta, caracterização, documentação, intercâmbio de conhecimentos do germoplasma desses recursos genéticos.
Chronic Kidney Disease Risk in African and Caribbean Populations With HIV
We conducted an observational cohort study of end-stage kidney disease (ESKD) in
>7,000 African and Caribbean people with HIV in the UK. Using Poisson regression
and East Africans as the reference group, the adjusted incidence rate ratio (95% CI) of
ESKD was 3.14 (1.26, 7.84) in Southern Africans, 6.35 (2.53, 15.96) in West Africans,
and 5.26 (1.91, 14.43) in Caribbeans. Higher CD4 cell count and suppressed HIV
replication were associated with reduced risk of ESKD. The risk of ESKD varied among
HIV positive people of African heritage, with the highest rates observed in those of
West African descent
Detection and follow-up of chronic obstructive pulmonary disease (COPD) and risk factors in the Southern Cone of Latin America. the pulmonary risk in South America (PRISA) study
<p>Abstract</p> <p>Background</p> <p>The World Health Organization has estimated that by 2030, chronic obstructive pulmonary disease will be the third leading cause of death worldwide. Most knowledge of chronic obstructive pulmonary disease is based on studies performed in Europe or North America and little is known about the prevalence, patient characteristics and change in lung function over time in patients in developing countries, such as those of Latin America. This lack of knowledge is in sharp contrast to the high levels of tobacco consumption and exposure to biomass fuels exhibited in Latin America, both major risk factors for the development of chronic obstructive pulmonary disease. Studies have also demonstrated that most Latin American physicians frequently do not follow international chronic obstructive pulmonary disease diagnostic and treatment guidelines. The PRISA Study will expand the current knowledge regarding chronic obstructive pulmonary disease and risk factors in Argentina, Chile and Uruguay to inform policy makers and health professionals on the best policies and practices to address this condition.</p> <p>Methods/Design</p> <p>PRISA is an observational, prospective cohort study with at least four years of follow-up. In the first year, PRISA has employed a randomized three-staged stratified cluster sampling strategy to identify 6,000 subjects from Marcos Paz and Bariloche, Argentina, Temuco, Chile, and Canelones, Uruguay. Information, such as comorbidities, socioeconomic status and tobacco and biomass exposure, will be collected and spirometry, anthropometric measurements, blood sampling and electrocardiogram will be performed. In year four, subjects will have repeat measurements taken.</p> <p>Discussion</p> <p>There is no longitudinal data on chronic obstructive pulmonary disease incidence and risk factors in the southern cone of Latin America, therefore this population-based prospective cohort study will fill knowledge gaps in the prevalence and incidence of chronic obstructive pulmonary disease, patient characteristics and changes in lung function over time as well as quality of life and health care resource utilization. Information gathered during the PRISA Study will inform public health interventions and prevention practices to reduce risk of COPD in the region.</p
Hsp90 orchestrates transcriptional regulation by Hsf1 and cell wall remodelling by MAPK signalling during thermal adaptation in a pathogenic yeast
Acknowledgments We thank Rebecca Shapiro for creating CaLC1819, CaLC1855 and CaLC1875, Gillian Milne for help with EM, Aaron Mitchell for generously providing the transposon insertion mutant library, Jesus Pla for generously providing the hog1 hst7 mutant, and Cathy Collins for technical assistance.Peer reviewedPublisher PD
- …