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

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Biochemical properties of the major proteins from Rhodnius prolixus eggshell

15 p. : il.Two proteins from the eggshell of Rhodnius prolixus were isolated, characterized and named Rp30 and Rp45 according to their molecular masses. Purified proteins were used to obtain specific antiserum which was later used for immunolocalization. The antiserum against Rp30 and Rp45 detected their presence inside the follicle cells, their secretion and their association with oocyte microvilli. Both proteins are expressed during the final stage of vitellogenesis, preserved during embryogenesis and discarded together with the eggshell. The amino terminals were sequenced and both proteins were further cloned using degenerated primers. The amino acid sequences appear to have a tripartite arrangement with a highly conserved central domain which presents a repetitive motif of valine–proline–valine (VPV) at intervals of 15 amino acid residues. Their amino acid sequence showed no similarity to any known eggshell protein. The expression of these proteins was also investigated; the results demonstrated that this occurred strictly in choriogenic follicles. Antifungal activity against Aspergillus niger was found to be associated with Rp45 but not with Rp30. A. niger exposed to Rp45 protein induced growth inhibition and several morphological changes such as large vacuoles, swollen mitochondria, multi-lamellar structures and a disorganized cell wall as demonstrated by electron microscopy analysis

The Dengue Vector <em>Aedes aegypti</em> Contains a Functional High Mobility Group Box 1 (HMGB1) Protein with a Unique Regulatory C-Terminus

<div><p>The mosquito <em>Aedes aegypti</em> can spread the dengue, chikungunya and yellow fever viruses. Thus, the search for key molecules involved in the mosquito survival represents today a promising vector control strategy. High Mobility Group Box (HMGB) proteins are essential nuclear factors that maintain the high-order structure of chromatin, keeping eukaryotic cells viable. Outside the nucleus, secreted HMGB proteins could alert the innate immune system to foreign antigens and trigger the initiation of host defenses. In this work, we cloned and functionally characterized the HMGB1 protein from <em>Aedes aegypti</em> (AaHMGB1). The AaHMGB1 protein typically consists of two HMG-box DNA binding domains and an acidic C-terminus. Interestingly, AaHMGB1 contains a unique alanine/glutamine-rich (AQ-rich) C-terminal region that seems to be exclusive of dipteran HMGB proteins. AaHMGB1 is localized to the cell nucleus, mainly associated with heterochromatin. Circular dichroism analyses of AaHMGB1 or the C-terminal truncated proteins revealed α-helical structures. We showed that AaHMGB1 can effectively bind and change the topology of DNA, and that the AQ-rich and the C-terminal acidic regions can modulate its ability to promote DNA supercoiling, as well as its preference to bind supercoiled DNA. AaHMGB1 is phosphorylated by PKA and PKC, but not by CK2. Importantly, phosphorylation of AaHMGB1 by PKA or PKC completely abolishes its DNA bending activity. Thus, our study shows that a functional HMGB1 protein occurs in <em>Aedes aegypt</em> and we provide the first description of a HMGB1 protein containing an AQ-rich regulatory C-terminus.</p> </div

Schematic diagram and SDS-PAGE of the recombinant AaHMGB1 proteins used in this study.

<p>(A) Diagram of the recombinant 6×-his-tagged proteins: AaHMGB1, consists of two DNA-binding domains, the HMG box A and HMG box B, a alanine/glutamine-rich (AQ-rich) domain and a short acidic C-terminal domain; AaHMGB1-ΔC lacks only the short acidic C-terminal domain; AaHMGB1-ΔAQ lacks only the AQ-rich domain; AaHMGB1-ΔAQC lacks the entire C-terminus, including the AQ-rich and the short acidic C-terminal domains. (B) SDS-PAGE of the purified recombinant proteins. One microgram of each construct was loaded and analyzed on a 12% SDS-PAGE gel.</p

Analysis of secondary and tertiary structures of AaHMGB1 proteins.

<p>(A) CD spectra of AaHMGB1 (black line), ΔC (red line), ΔQC (green line) and ΔAQC (blue line) were performed at 25°C. Spectra were averaged from three scans at a 30 nm/min speed recorded from 190 to 260 nm, and the buffer baselines were subtracted from their respective sample spectra. (B) AaHMGB1 (black line), ΔC (red line), ΔQC (green line) and ΔAQC (blue line) were analyzed using fluorescence spectroscopy, either in the absence (native state, solid lines) or presence of 8 M urea (denatured state, dashed lines), in order to evaluate tertiary structure content. The excitation wavelength was fixed at 280 nm and the emission spectrum was recorded from 300 nm to 420 nm. Experiments were performed at 25°C.</p

<i>In vitro</i> phosphorylation of AaHMGB1.

<p>(A) One microgram of AaHMGB1 proteins were subjected to an <i>in vitro</i> kinase assay with commercial kinases (CK2, PKA and PKC) and radiolabeled [γ-³²P] ATP. Phosphorylations were analyzed by 12% SDS-PAGE (top panel) and autoradiography (bottom panel). <i>Schistosoma mansoni</i> HMGB1 (SmHMGB1) was used as a positive control for CK2 phosphorylation <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0040192#pone.0040192-deAbreudaSilva1" target="_blank">[37]</a>. (B) Immunoprecipitation of endogenous phosphorylated AaHMGB1. Total protein extract from adult mosquitoes were immune precipitated with pre-immune serum or anti-HMGB1 antibody (lane 3). Western blot analysis was carried out with anti-phospho serine monoclonal antibody (lanes 2 and 3). Endogenous AaHMGB1 (from the protein extract) was reacted against polyclonal anti-AaHMGB1 antibody (lane 1).</p