Pervasive gaps in Amazonian ecological research

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

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

Acute and chronic hypermethioninemia alter Na+,K+-ATPase activity in rat hippocampus : prevention by antioxidants

In the current study we initially investigated the influence of antioxidants (vitamins E plus C) on the effect mediated by acute and chronic administration of methionine (Met) on Na+,K+-ATPase activity in rat hippocampus. We also verified whether the alterations on the enzyme after administration of Met and/or antioxidants were associated with changes in relative expression of Na+,K+-ATPase catalytic subunits (isoforms α1, α2 and α3). For acute treatment, young rats received a single subcutaneous injection of Met or saline (control) and were sacrificed 12 h later. In another set of experiments, rats were pretreated for 1 week with daily intraperitoneal administration of vitamins E (40 mg/kg) and C (100 mg/kg) or saline. After that, rats received a single injection of Met or saline and were killed 12 h later. For chronic treatment, Met was administered to rats from the 6th to the 28th day of life; controls and treated rats were sacrificed 12 h after the last injection. In parallel to chronic treatment, rats received a daily intraperitoneal injection of vitamins E and C from the 6th to the 28th day of life and were killed 12 h after the last injection. Results showed that administration of antioxidants partially prevented the inhibition of enzyme activity caused by acute and chronic hypermethioninemia. Besides, we demonstrated that transcription of catalytic subunits of Na+,K+-ATPase was not altered by chronic and acute exposure to Met and/or vitamins E plus C. These data strongly suggest the oxidative damage as one possible mechanism involved in the reduction of Na+,K+-ATPase activity caused by hypermethioninemia and if confirmed in human beings, we might propose the use of antioxidants as an adjuvant therapy in hypermethioninemic patients

Macroscopic morphology and arterial vascular supply of thymus in fowls (Gallus gallus domesticus) of Red Bro Cou Nu lineag - doi: 10.4025/actascibiolsci.v34i4.8529

Twenty-eight fowls (Gallus gallus domesticus) of the Red Bro Cou Nu lineage were studied. They were about 35 days old and had their arteries filled with Neoprene Latex 450", aqueous solution at 50%, stained with specific pigment (Globo S/A, Tintas e Pigmentos), and then fixed in aqueous solution of formaldehyde at 10%. The present study aimed to quantify the thymic lobes and identify the main arteries responsible for the blood supply of these lobes and their frequencies. The number of thymic lobes on the right antimere varied from two to 11, with a greater frequency of 8 lobes; and the left antimere showed a variation from one to eight, with a greater frequency of five lobes. The arteries destined to the thymus were composed by direct and indirect branches of the following arteries: left and right common vagus nerve, left and right cranial thyroid, left and right caudal thyroid, left and right ascending esophageal, right ingluvial, left and right cutaneous, and right common carotid. The right thymic lobes, regardless their origin, received from eight to 27 vascular branches, and the left thymic lobes, from eight to 24 branches.

Resumo em andamento - Arquitetura e Urbanismo

Resumo em andamento - Arquitetura e Urbanism

Organizational factors associated with adherence to low tidal volume ventilation: a secondary analysis of the CHECKLIST-ICU database

Background: Survival benefit from low tidal volume (VT) ventilation (LTVV) has been demonstrated for patients with acute respiratory distress syndrome (ARDS), and patients not having ARDS could also benefit from this strategy. Organizational factors may play a role on adherence to LTVV. The present study aimed to identify organizational factors with an independent association with adherence to LTVV. Methods: Secondary analysis of the database of a multicenter two-phase study (prospective cohort followed by a cluster-randomized trial) performed in 118 Brazilian intensive care units. Patients under mechanical ventilation at day 2 were included. LTVV was defined as a VT ≤ 8 ml/kg PBW on the second day of ventilation. Data on the type and number of beds of the hospital, teaching status, nursing, respiratory therapists and physician staffing, use of structured checklist, and presence of protocols were tested. A multivariable mixed-effect model was used to assess the association between organizational factors and adherence to LTVV. Results: The study included 5719 patients; 3340 (58%) patients received LTVV. A greater number of hospital beds (absolute difference 7.43% [95% confidence interval 0.61–14.24%]; p = 0.038), use of structured checklist during multidisciplinary rounds (5.10% [0.55–9.81%]; p = 0.030), and presence of at least one nurse per 10 patients during all shifts (17.24% [0.85–33.60%]; p = 0.045) were the only three factors that had an independent association with adherence to LTVV. Conclusions: Number of hospital beds, use of a structured checklist during multidisciplinary rounds, and nurse staffing are organizational factors associated with adherence to LTVV. These findings shed light on organizational factors that may improve ventilation in critically ill patients

Increased interregional virus exchange and nucleotide diversity outline the expansion of chikungunya virus in Brazil

Abstract The emergence and reemergence of mosquito-borne diseases in Brazil such as yellow fever, zika, chikungunya, and dengue have had serious impacts on public health. Concerns have been raised due to the rapid dissemination of the chikungunya virus across the country since its first detection in 2014 in Northeast Brazil. In this work, we carried out on-site training activities in genomic surveillance in partnership with the National Network of Public Health Laboratories that have led to the generation of 422 chikungunya virus genomes from 12 Brazilian states over the past two years (2021–2022), a period that has seen more than 312 thousand chikungunya fever cases reported in the country. These genomes increased the amount of available data and allowed a more comprehensive characterization of the dispersal dynamics of the chikungunya virus East-Central-South-African lineage in Brazil. Tree branching patterns revealed the emergence and expansion of two distinct subclades. Phylogeographic analysis indicated that the northeast region has been the leading hub of virus spread towards other regions. Increased frequency of C > T transitions among the new genomes suggested that host restriction factors from the immune system such as ADAR and AID/APOBEC deaminases might be driving the genetic diversity of the chikungunya virus in Brazil