Nonlocal Diffusion Elliptic System Modelling The Behaviour Of a Bacteria And a Living Nutrient

In this paper, we discuss the existence and uniqueness of coexistence states for a class of non-local elliptic system. This problem models the behaviour of a bacteria and a living nutrient, whose diffusion depends on the population of the bacteria in a non-local and nonlinear way. Mainly, we employ bifurcation methods and the Implicit Function Theorem to obtain the existence and uniqueness of positive solution.Comment: 15 pages and 2 figure

The role of protected areas in the avoidance of anthropogenic conversion in a high pressure region : a matching method analysis in the core region of the brazilian cerrado

Global efforts to avoid anthropogenic conversion of natural habitat rely heavily on the establishment of protected areas. Studies that evaluate the effectiveness of these areas with a focus on preserving the natural habitat define effectiveness as a measure of the influence of protected areas on total avoided conversion. Changes in the estimated effectiveness are related to local and regional differences, evaluation methods, restriction categories that include the protected areas, and other characteristics. The overall objective of this study was to evaluate the effectiveness of protected areas to prevent the advance of the conversion of natural areas in the core region of the Brazil’s Cerrado Biome, taking into account the influence of the restriction degree, governmental sphere, time since the establishment of the protected area units, and the size of the area on the performance of protected areas. The evaluation was conducted using matching methods and took into account the following two fundamental issues: control of statistical biases caused by the influence of covariates on the likelihood of anthropogenic conversion and the non-randomness of the allocation of protected areas throughout the territory (spatial correlation effect) and the control of statistical bias caused by the influence of auto-correlation and leakage effect. Using a sample design that is not based on ways to control these biases may result in outcomes that underestimate or overestimate the effectiveness of those units. The matching method accounted for a bias reduction in 94–99% of the estimation of the average effect of protected areas on anthropogenic conversion and allowed us to obtain results with a reduced influence of the auto-correlation and leakage effects. Most protected areas had a positive influence on the maintenance of natural habitats, although wide variation in this effectiveness was dependent on the type, restriction, governmental sphere, size and age group of the unit

Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie

HIV-infected patients show functionally defective high-density lipoprotein (HDL) paralleled with changes in HDL-associated proteins

Purpose of the study Epidemiological studies have consistently demonstrated an inverse association between plasma HDL concentrations and cardiovascular risk. Although this cardioprotective role has been mainly attributed to its role in promoting cellular cholesterol efflux, there is an emerging interest in the anti-inflammatory and antioxidant properties of HDL. The aim of the study is to investigate the anti-inflammatory properties of HDL isolated from HIV-infected patients. Methods Cross-sectional study of 113 HIV-infected patients and 70 non-infected control subjects without evident CVD. From each subject, HDL was isolated by ultracentrifugation and its anti-inflammatory status was tested as its ability to inhibit MCP-1-induced migration of the monocytic cell line THP-1 using transwell cell culture chamber inserts with micropore filters of 5 microns pore size. HDL-associated proteins were measured by commercial ELISAs. Results Twenty-three HIV-infected patients were ART-na&#x00EF;ve (32&#x00B1;15 years, 66.7% male) and ninety were currently on ART (46&#x00B1;11 years, 78.9 % male). Most patients on ART (91.1%) had undetectable viral load (&#60;50 copies/mL). When compared to healthy subjects, both na&#x00EF;ve and treated HIV-infected patients had lower plasma HDL-cholesterol levels (na&#x00EF;ve: 45&#x00B1;12, ART: 50&#x00B1;10, controls: 55&#x00B1;10 mg/dL, p&#60;0.05). HDL isolated from HIV na&#x00EF;ve patients showed a significantly reduced anti-inflammatory activity (THP-1 monocyte migration capacity was 203% times higher in HIV patients than in control subjects). The anti-inflammatory activity of HDL from ART-treated HIV-infected patients was significantly improved when compared to na&#x00EF;ve patients, although it remained significantly lower than controls (130% THP-1 monocyte migration vs controls). HDL from HIV-infected patients had a decreased concentration of the anti-inflammatory proteins Apo A1 (controls: 2.1&#x00B1;0.3, na&#x00EF;ve: 1.4&#x00B1;0.2, ART: 1.6&#x00B1;0.1 mg/ml) and LCAT (controls: 0.53&#x00B1;0.09, na&#x00EF;ve: 0.34&#x00B1;0.06, ART: 0.48&#x00B1;0.05 &#x03BC;g/ml), and increased of the pro-inflammatory protein serum amiloid (controls: 1.42&#x00B1;0.53, na&#x00EF;ve: 3.23&#x00B1;1.29, ART: 2.72&#x00B1;0.70 &#x03BC;g/ml) than healthy controls. Conclusions Our data demonstrate HIV-infected patients, even with effective therapy, showed a marked reduction of HDL anti-inflammatory properties. This dysfunctional HDL seems to be associated with changes HDL composition and may contribute to the increased CVD risk observed in HIV infection