19 research outputs found

    Physical activity: a strategy to improve antibody response to a SARS-CoV-2 vaccine booster dose in patients with autoimmune rheumatic diseases.

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    Physical activity associates with improved immunogenicity following a 2-dose schedule of CoronaVac (Sinovac's inactivated SARS-CoV-2 vaccine) in patients with autoimmune rheumatic diseases (ARD). This study evaluates whether physical activity impacts vaccine-induced antibody responses to a booster dose in this population. This was a phase-4 trial conducted in Sao Paulo, Brazil. Patients with ARD underwent a 3-dose schedule of CoronaVac. One month after the booster, we assessed seroconversion rates of anti-SARS-CoV-2 S1/S2 IgG, geometric mean titers of anti-S1/S2 IgG, frequency of positive neutralizing antibodies, and neutralizing activity. Physical activity was assessed through questionnaire. Physically active (n = 362) and inactive (n = 278) patients were comparable for most characteristics; however, physically active patients were younger (P<.01) and had a lower frequency of chronic inflammatory arthritis (P<.01). Adjusted models showed that physically active patients had -2 times odds of seroconversion rates (OR: 2.09; 95% confidence interval, 1.22 to 3.61), -22% greater geometric mean titers of anti-S1/S2 IgG (22.09%; 95% confidence interval, 3.91 to 65.60), and -7% greater neutralizing activity (6.76%; 95% confidence interval, 2.80 to 10.72) than inactive patients. Patients with ARD who are physically active have greater odds of experiencing better immunogenicity to a booster dose of CoronaVac. These results support the recommendation of physical activity to improve vaccination responses, particularly for immunocompromised individuals

    No associations between physical activity and immunogenicity in SARS-CoV-2 seropositive patients with autoimmune rheumatic diseases prior to and after vaccination.

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    To investigate the association between physical activity and immunogenicity among SARS-CoV-2 seropositive patients with autoimmune rheumatic diseases prior to and following a 2-dose schedule of CoronaVac (Sinovac inactivated vaccine). This was a prospective cohort study within an open-label, single-arm, phase 4 vaccination trial conducted in Sao Paulo, Brazil. In this substudy, only SARS-CoV-2 seropositive patients were included. Immunogenicity was assessed by seroconversion rates of total anti-SARS-CoV-2 S1/S2 immunoglobulin G (IgG), geometric mean titers of anti-S1/S2 IgG, frequency of positive neutralizing antibodies, and neutralizing activity before and after vaccination. Physical activity was assessed through a questionnaire. Model-based analyses were performed controlling for age (30 kg/m2), and use of prednisone, immunosuppressants, and biologics. A total of 180 seropositive autoimmune rheumatic disease patients were included. There was no association between physical activity and immunogenicity before and after vaccination. This study suggests that the positive association between physical activity and greater antibody responses seen in immunocompromised individuals following vaccination is overridden by previous SARS-CoV-2 infection, and does not extend to natural immunity

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    The impact of the Forest Stewardship Council (FSC) pesticide policy on the management of leaf-cutting ants and termites in certified forests in Brazil

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    International audience• Key messageThe recommendations accompanying pesticide derogations from the FSC are not efficient for the management of leaf-cutting ants and termites in certified forest plantations in Brazil compared with chemical control using insecticides. FSC recommendations ignore the biological and ecological features of pests and forest plantations in Brazil when they set global rules for forest certification

    Double-Blind Clinical Trial of Arginine Supplementation in the Treatment of Adult Patients with Sickle Cell Anaemia

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    Background. Sickle cell anaemia (SCA) is the most prevalent monogenic disease in Brazil. In SCA, haemoglobin S (HbS) is formed, which modifies red blood cell morphology. Intravascular haemolysis occurs, in which free Hb and free radicals degrade nitric oxide (NO) and release arginase, which reduces arginine levels. Because arginine is a substrate for NO formation, this decrease leads to reduced NO (vasodilator) synthesis. SCA treatment uses hydroxyurea (HU) to maintain high foetal haemoglobin (HbF) levels and reduces HbS to avoid haemolytic episodes. Objective. To analyse the efficacy of L-arginine as an adjuvant in the treatment of SCA patients. Setting. The State Blood Centre of Ceará, Brazil. Methods. This was a randomized double-blind clinical study of adults with SCA with continuous use of HU at the State Blood Centre of Ceará. The clinical study enrolled 25 patients receiving HU + L-arginine (500 mg) and 25 patients receiving HU + placebo. The treatment was carried out over four months. Laboratory tests were performed to determine the levels of the following: (1) complete blood count; (2) nitrite + nitrate; (3) HbF; and (4) reticulocytes. The clinical experiments were performed by a haematologist. The main outcome measures were nitrite and pain. Results. Statistical analysis showed that the levels of NO were increased in the study group, and there was also a reduction in pain frequency using a pain frequency scale by day, week, and month. The levels of nitrite plus nitrate in the group receiving placebo plus HU did not change among the times evaluated (38.27 ± 17.27 mg/L, 39.49 ± 12.84 mg/L, 34.45 ± 11.25 mg/L, p >0.05), but in the patients who received supplementation with L-arginine plus HU, a significant increase in nitrite plus nitrate levels was observed between M0 and M4 (36.55 ± 20.23 mg/L versus 48.64 ± 20.63 mg/L, p =0.001) and M2 and M4 (35.71 ± 15.11 mg/L versus 48.64 ± 20.63 mg/L, p <0.001). It is important to note that the increase in nitrite plus nitrate levels occurred only in the fourth month of follow-up of patients in the treatment group, showing that at least 4 months of supplementation with L-arginine is necessary to show an increase in these metabolites in the serum. Conclusion. The use of L-arginine as a coadjuvant in the treatment of sickle cell anaemia may function as a potential tool for pain relief, consequently improving the life of patients
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