Unravelling the genome of the brackish water malaria vector Anopheles aquasalis.

Malaria is a severe public health problem in several developing tropical and subtropical countries. Anopheles aquasalis is the primary coastal malaria vector in Central and South America and the Caribbean Islands, and it has the peculiar feature of living in water with large changes in salinity. Recent research has recognised An. aquasalis as an important model for studying the interactions of murine and human Plasmodium parasites. This study presents the complete genome of An. aquasalis and offers insights into its evolution and physiology. The genome is similar in size and gene content to other Neotropical anophelines, with 162 Mb and 12,446 protein-coding genes. There are 1387 single-copy orthologs at the Diptera level (eg. An. gambiae, An. darlingi and Drosophila melanogaster). An. aquasalis diverged from An. darlingi, the primary malaria vector in inland South America, nearly 20 million years ago. Proteins related to ion transport and metabolism belong to the most abundant gene families with 660 genes. We identified gene families relevant to osmosis control (e.g., aquaporins, vacuolar-ATPases, Na+/K+-ATPases, and carbonic anhydrases). Evolutionary analysis suggests that all osmotic regulation genes are under strong purifying selection. We also observed low copy number variation in insecticide resistance and immunity-related genes for all known classical pathways. The data provided by this study offers candidate genes for further studies of parasite-vector interactions and for studies on how anophelines of brackish water deal with the high fluctuation in water salinity. We also established data and insights supporting An. aquasalis as an emerging Neotropical malaria vector model for genetic and molecular studies.

Detection of HPV DNA in vaginal samples self-collected by women living with HIV treated through the Brazilian public health system: Prevalence and analysis of risk factors.

BACKGROUND: Women living with human immunodeficiency virus (HIV) (WLWH) are more likely to be infected with the oncogenic human papillomavirus (HPV). We assessed the prevalence of high-risk (HR) (16/18/31/33/35/39/45/51/52/56/58/59/68/73/82), probable high-risk (pHR) (26/53/66), and low-risk (LR) (6/11/40/42/43/44/54/61/70) HPV types and their associated risk factors. METHODS: This cross-sectional study of WLWH aged 18-64 years included one laboratory and eight HIV-specialty healthcare facilities in the pilot network. Descriptive statistics were used to assess sociodemographic and behavioral characteristics. Adjusted analyses were conducted to evaluate risk factors associated with HR and/or pHR HPV infection in WLWH. RESULTS: From May/2021 to May/2022, 1,914 (92.5%) WLWH participated in the pilot study and had valid HPV-DNA results of self-collected vaginal samples. The median age of the participants was 45 years, 60.1% had ≥ 9 years of schooling, 80.5% were ≤ 18 years at first sexual intercourse, and 51.7% had > 4 sexual partners throughout life. The prevalence of any HPV type, HR HPV, pHR HPV, and LR HPV was 65.8%, 49.6%, 16.7%, and 40.0%, respectively. Age was inversely associated with pHR and/or HR-HPV (p < 0.001), and education level was inversely associated with HR-HPV (p = 0.003) types. Any HR or pHR was associated with being single (p = 0.029) and exchanging sex for drugs (p = 0.037). CONCLUSIONS: The prevalence of HPV, especially HR HPV, among WLWH is high in Brazil, highlighting the need for HPV screening in this population. Self-collection of vaginal samples is an important strategy for increasing testing access.

Temporal patterns of cytokine and injury biomarkers in hospitalized COVID-19 patients treated with methylprednisolone.

Background: The novel coronavirus disease 2019 (COVID-19) presents with complex pathophysiological effects in various organ systems. Following the COVID-19, there are shifts in biomarker and cytokine equilibrium associated with altered physiological processes arising from viral damage or aggressive immunological response. We hypothesized that high daily dose methylprednisolone improved the injury biomarkers and serum cytokine profiles in COVID-19 patients. Methods: Injury biomarker and cytokine analysis was performed on 50 SARS-Cov-2 negative controls and 101 hospitalized severe COVID-19 patients: 49 methylprednisolone-treated (MP group) and 52 placebo-treated serum samples. Samples from the treated groups collected on days D1 (pre-treatment) all the groups, D7 (2 days after ending therapy) and D14 were analyzed. Luminex assay quantified the biomarkers HMGB1, FABP3, myoglobin, troponin I and NTproBNP. Immune mediators (CXCL8, CCL2, CXCL9, CXCL10, TNF, IFN-γ, IL-17A, IL-12p70, IL-10, IL-6, IL-4, IL-2, and IL-1ß) were quantified using cytometric bead array. Results: At pretreatment, the two treatment groups were comparable demographically. At pre-treatment (D1), injury biomarkers (HMGB1, TnI, myoglobin and FABP3) were distinctly elevated. At D7, HMGB1 was significantly higher in the MP group (p=0.0448) compared to the placebo group, while HMGB1 in the placebo group diminished significantly by D14 (p=0.0115). Compared to healthy control samples, several immune mediators (IL-17A, IL-6, IL-10, MIG, MCP-1, and IP-10) were considerably elevated at baseline (all p≤0.05). At D7, MIG and IP-10 of the MP-group were significantly lower than in the placebo-group (p=0.0431, p=0.0069, respectively). Longitudinally, IL-2 (MP-group) and IL-17A (placebo-group) had increased significantly by D14. In placebo group, IL-2 and IL-17A continuously increased, as IL-12p70, IL-10 and IP-10 steadily decreased during follow-up. The MP treated group had IL-2, IFN-γ, IL-17A and IL-12p70 progressively increase while IL-1ß and IL-10 gradually decreased towards D14. Moderate to strong positive correlations between chemokines and cytokines were observed on D7 and D14. Conclusion: These findings suggest MP treatment could ameliorate levels of myoglobin and FABP3, but appeared to have no impact on HMGB1, TnI and NTproBNP. In addition, methylprednisolone relieves the COVID-19 induced inflammatory response by diminishing MIG and IP-10 levels. Overall, corticosteroid (methylprednisolone) use in COVID-19 management influences the immunological molecule and injury biomarker profile in COVID-19 patients.

Genetic polymorphisms of CYP2B6*6, CYP2C8*3 and CYP2D6*4 in vivax malaria patients from Brazilian Amazon

Abstract Genetic variability in the host metabolism of antimalarial drugs influenced by the polymorphisms of cytochrome P450 (CYP) could lead to significant changes in antimalarial treatment response. However, little is known about the frequency of alleles CYP2B6, CYP2C8, and CYP2D6 in an Amazonian population, especially with vivax malaria. Therefore, this study aimed to determine the frequency of CYP alleles CYP2B6*6, CYP2C8*3, and CYP2D6*4 in patients with vivax malaria. The study included 231 patients with vivax malaria treated at a health care reference in Manaus, northern Brazil. A sample of peripheral blood from each subject was collected to perform DNA extraction and genotypic analysis. Genotyping of polymorphisms was performed by allelic discrimination using Real-time polymerase chain reaction. The CYP2D6*4 allele was the most prevalent among patients who developed severe malaria. The frequencies of the CYP2B6*6 and CYP2D6*4 were not different between the severe and uncomplicated malaria. There was a significant association between heterozygous CYP2D6*4 and severe cases of malaria. The results are in agreement with other reports described in the literature for different populations. Future studies are needed to understand the clinical implications of the polymorphisms in patients with vivax malaria.

Detection of HPV DNA in vaginal samples self-collected by women living with HIV treated through the Brazilian public health system: Prevalence and analysis of risk factors

ABSTRACT Background: Women living with human immunodeficiency virus (HIV) (WLWH) are more likely to be infected with the oncogenic human papillomavirus (HPV). We assessed the prevalence of high-risk (HR) (16/18/31/33/35/39/45/51/52/56/58/59/68/73/82), probable high-risk (pHR) (26/53/66), and low-risk (LR) (6/11/40/42/43/44/54/61/70) HPV types and their associated risk factors. Methods: This cross-sectional study of WLWH aged 18-64 years included one laboratory and eight HIV-specialty healthcare facilities in the pilot network. Descriptive statistics were used to assess sociodemographic and behavioral characteristics. Adjusted analyses were conducted to evaluate risk factors associated with HR and/or pHR HPV infection in WLWH. Results: From May/2021 to May/2022, 1,914 (92.5%) WLWH participated in the pilot study and had valid HPV-DNA results of self-collected vaginal samples. The median age of the participants was 45 years, 60.1% had ≥ 9 years of schooling, 80.5% were ≤ 18 years at first sexual intercourse, and 51.7% had > 4 sexual partners throughout life. The prevalence of any HPV type, HR HPV, pHR HPV, and LR HPV was 65.8%, 49.6%, 16.7%, and 40.0%, respectively. Age was inversely associated with pHR and/or HR-HPV (p < 0.001), and education level was inversely associated with HR-HPV (p = 0.003) types. Any HR or pHR was associated with being single (p = 0.029) and exchanging sex for drugs (p = 0.037). Conclusions: The prevalence of HPV, especially HR HPV, among WLWH is high in Brazil, highlighting the need for HPV screening in this population. Self-collection of vaginal samples is an important strategy for increasing testing access.

Malaria and COVID-19 coinfection in a non-malaria-endemic area in Brazil

ABSTRACT Differential diagnosis of coronavirus disease 2019 (COVID-19) from other febrile diseases is one of several challenges imposed by the pandemic. We present a case of severe malaria and COVID-19 coinfection in a non-malaria-endemic region. A 44-year-old female with malaise, fever, hypotension, jaundice, and enlarged liver and spleen was admitted to the intensive care unit. Reverse transcription-quantitative PCR results for severe acute respiratory syndrome coronavirus 2 were positive. Rapid tests, microscopy, and quantitative PCR were positive for Plasmodium vivax. Cytokine storm profiles were identified. We could not determine whether the severe vivax malaria in our patient was triggered by COVID-19 coinfection.

Searching for new antifungals for the treatment of cryptococcosis

ABSTRACT There is a consensus that the antifungal repertoire for the treatment of cryptococcal infections is limited. Standard treatment involves the administration of an antifungal drug derived from natural sources (i.e., amphotericin B) and two other drugs developed synthetically (i.e., flucytosine and fluconazole). Despite treatment, the mortality rates associated with fungal cryptococcosis are high. Amphotericin B and flucytosine are toxic, require intravenous administration, and are usually unavailable in low-income countries because of their high cost. However, fluconazole is cost-effective, widely available, and harmless with regard to its side effects. However, fluconazole is a fungistatic agent that has contributed considerably to the increase in fungal resistance and frequent relapses in patients with cryptococcal meningitis. Therefore, there is an unquestionable need to identify new alternatives or adjuvants to conventional drugs for the treatment of cryptococcosis. A potential antifungal agent should be able to kill cryptococci and "bypass" the virulence mechanism of the yeast. Furthermore, it should have fungicidal action, low toxicity, high selectivity, easily penetrate the central nervous system, and widely available. In this review, we describe cryptococcosis, its conventional therapy, and failures arising from the use of drugs traditionally considered to be the reference standard. Additionally, we present the approaches used for the discovery of new drugs to counteract cryptococcosis, ranging from the conventional screening of natural products to the inclusion of structural modifications to optimize anticryptococcal activity, as well as drug repositioning and combined therapies.

Kidney function and daily emtricitabine/tenofovir disoproxil fumarate pre-exposure prophylaxis against HIV: results from the real-life multicentric demonstrative project PrEP Brazil.

BACKGROUND: Pre-Exposure Prophylaxis (PrEP) has demonstrated efficacy in the reduction of sexually transmitted HIV infections. The prolonged use of tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) co-formulation (TDF/FTC), however, may result in augmented risk of renal toxicity. We aimed to evaluate changes in the estimated Glomerular Filtration Rate (eGFR) in a real-world population setting of participants enrolled in PrEP Brazil, a 48-week prospective, open-label, demonstration study to assess the feasibility of daily oral TDF/FTC used by men who have sex with men and transgender women at high-risk of HIV infection, all over 18 years old. METHODS: Kidney function was assessed by serial measurement of serum creatinine and eGFR with the Modification of Diet in Renal Disease Study (MDRD) formula on weeks 4, 12, 24, 36 and 48. Adherence to PrEP was assessed by dosing TDF concentration in dried blood spots at weeks 4 and 48, measured by liquid chromatography-mass spectrometry or mass spectrometry. RESULTS: Of 392 participants completing the 48-week follow-up protocol with TDF blood detectable levels and eGFR measures, 43.1% were young adults, of Caucasian ethnic background (57.9%), with BMI below 30 kg/m2, without arterial hypertension. At screening, median eGFR was 93.0 mL/min/1.73 m2. At week 4 follow-up, 90 (23% of the study population) participants presented reductions in eGFR greater than 10 mL/min/1.73 m2 as compared to baseline eGFR, some as large as 59 mL/min/1.73 m2, but with no clinical outcomes (adverse events and renal adverse events) severe enough to demand TDF/FTC discontinuation. A negative relationship was observed between TDF blood levels and eGFR at weeks 4 (r = - 0.005; p < 0.01) and 48 (r = - 0.006; p < 0.01). CONCLUSIONS: These results suggest that the renal function profile in individuals on TDF/FTC may be assessed on week 4 and then only annually, allowing a more flexible medical follow-up in primary care centers.

Arranjos tecnoassistenciais no enfrentamento da pandemia da COVID-19 na perspectiva de gestores / Technical-assistance arrangements in coping with the COVID-19 pandemic from the managers' perspective / Preparativos tecnoasistenciales para enfrentar la pandemia de COVID-19 desde la perspectiva de los gestores

Resumo Objetivo: descrever os arranjos tecnoassistenciais desenvolvidos no âmbito da gestão do trabalho na rede de atenção à pandemia de COVID-19, na perspectiva de gestores. Método: pesquisa qualitativa, do tipo caso único incorporado, com 23 gestores de uma Rede de Atenção à Saúde. Análise aplicada em dois ciclos de codificação temática, com o auxílio do software ATLAS.ti. Resultados: os arranjos foram analisados em categorias vinculadas à: atenção à saúde; gestão; incorporação de tecnologias; implantação de hospital de campanha; e análise retrospectiva das experiências como um todo. Houve destaque para a implantação de fluxo de atendimentos, boletins de saúde virtuais, telemonitoramento, chatbots, uso de aplicativos, implantação de hospitais de campanha e da urgência básica no âmbito de Unidades Básicas de Saúde. Identificou-se a hiperjudicialização no sistema; fragilidades na gestão das informações, intersetorialidade e condução técnico-política em âmbito nacional; o protagonismo dos enfermeiros em cargos de gestão e para o enfrentamento da pandemia. Conclusão: apesar do despreparo dos serviços de saúde para o enfrentamento da pandemia, a resiliência dos atores promoveu dinamicidade e arranjos tecnoassistenciais no âmbito da gestão e do cuidado humanizado. O estudo tem potencial contribuição para qualificação das práticas de gestão e desenvolvimento de políticas públicas.

Abstract Objective: to describe the technical-assistance arrangements developed within the scope of work management in the COVID-19 pandemic care network, from the managers' perspective. Method: a qualitative research study, of the incorporated single case type, conducted with 23 managers of a Health Care Network. The analysis was applied in two thematic coding cycles, with the aid of the ATLAS.ti software. Results: the arrangements were analyzed in categories related to health care; management; incorporation of technologies; implementation of a field hospital; and retrospective analysis of the experiences as a whole. There was emphasis on the implementation of care flows, virtual health bulletins, Telemonitoring, chatbots, use of applications, and implementation of field hospitals and of basic urgency services within the scope of the Basic Health Units. Hyperjudicialization in the system was identified; as well as weaknesses in information management, intersectoriality and technical-political leadership at the national level; the role of nurses in management positions and for coping with the pandemic. Conclusion: despite the health services' unpreparedness to face the pandemic, the actors' resilience promoted dynamism and technical-assistance arrangements in the context of management and humanized care. The study has a potential to contribute to the qualification of the public policy management and development practices.

Resumen Objetivo: describir los preparativos tecnoasistenciales que se desarrollaron en el ámbito de la gestión del trabajo en la red de atención de la pandemia de COVID-19, desde la perspectiva de los gestores. Método: investigación cualitativa, del tipo caso único incorporado, con 23 gestores de una Red de Atención de Salud. Análisis aplicado en dos ciclos de codificación temática, con ayuda del software ATLAS.ti. Resultados: los preparativos fueron analizados en categorías relacionadas con: la atención de la salud; la administración; la incorporación de tecnologías; la implementación de un hospital de campaña; y el análisis retrospectivo de las experiencias en general. Se destacaron la implementación del flujo de atención, los boletines virtuales de salud, el telemonitoreo, los chatbots, el uso de aplicaciones, la implementación de hospitales de campaña y emergencias básicas en el ámbito de las Unidades Básicas de Salud. Se identificaron la hiperjudicialización en el sistema; las debilidades en la gestión de la información, la intersectorialidad y conducción técnico-política a nivel nacional; el protagonismo de los enfermeros en cargos de gestión y para hacer frente a la pandemia. Conclusión: a pesar de la falta de preparación de los servicios de salud para enfrentar la pandemia, la resiliencia de los actores promovió el dinamismo y los preparativos tecnoasistenciales en el ámbito de la gestión y de la atención humanizada. El estudio tiene una contribución potencial para la calificación de las prácticas de gestión y el desarrollo de políticas públicas.

Thrombotic microangiopathy associated with arboviral infection: Report of 3 cases.

Dengue fever and chikungunya are viral diseases that have spread rapidly throughout the world in recent decades. The occurrence of complications is well known, including prerenal acute kidney injury (AKI), which is usually thought to be caused by dehydration and fluid loss. Thrombotic microangiopathy (TMA) is an uncommon aggravation of dengue fever and chikungunya, with only a few cases described in the medical literature. The aim of this study is to present 3 cases of TMA associated with arboviral infection. Three patients with clinical history, laboratory test, and kidney biopsy results compatible with TMA were selected for the study, 2 of whom had a serological diagnosis of dengue fever and 1 of chikungunya. The 3 patients were followed up at the Federal University of Maranhão Hospital's Nephrology Service in 2018. A targeted gene panel sequencing (TGPS) plus multiple to atypical hemolytic uremic syndrome (aHUS) multiplex ligation-dependent probe amplification (MLPA) was performed in 2 of the patients and revealed in the patient 1 a heterozygous pathogenic variant in the gene THBD, as well as heterozygous deletions in CFH, CFHR1, and CFHR3. In the patient 2, there were heterozygous pathogenic variant in the genes CFI and CFB, in addition to heterozygous deletions in the genes CFHR1 and CFHR3. Both received treatment with eculizumab and undergone recovery of renal function. The third patient had TMA not classified as either aHUS or thrombotic thrombocytopenic purpura (TTP); he abandoned the treatment and returned to the service after 2 years for a dialysis emergency. Patients with arboviral infectious disease and changes that suggest TMA should have appropriate support to establish early diagnosis and useful treatment.

Acid pH Increases SARS-CoV-2 Infection and the Risk of Death by COVID-19.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can infect a broad range of human tissues by using the host receptor angiotensin-converting enzyme 2 (ACE2). Individuals with comorbidities associated with severe COVID-19 display higher levels of ACE2 in the lungs compared to those without comorbidities, and conditions such as cell stress, elevated glucose levels and hypoxia may also increase the expression of ACE2. Here, we showed that patients with Barrett's esophagus (BE) have a higher expression of ACE2 in BE tissues compared to normal squamous esophagus, and that the lower pH associated with BE may drive this increase in expression. Human primary monocytes cultured in reduced pH displayed increased ACE2 expression and higher viral load upon SARS-CoV-2 infection. We also showed in two independent cohorts of 1,357 COVID-19 patients that previous use of proton pump inhibitors is associated with 2- to 3-fold higher risk of death compared to those not using the drugs. Our work suggests that pH has a great influence on SARS-CoV-2 Infection and COVID-19 severity.

Non-lactational Infectious Mastitis in the Americas: A Systematic Review.

Background: Non-lactational infectious mastitis (NLIM) is an inflammatory breast disease with broad clinical presentation. Inadequate treatment can lead to chronic infections that cause breast deformities. NLIM information is limited, especially in the Americas. A systematic review and meta-analysis have been conducted here. Methods: Literature search was conducted in three databases (Lilacs, PubMed, and Scielo) on NLIM cases in the Americas. Demographic, epidemiological, clinical, radiological, and laboratory data were extracted. The main characteristics and results were also compared according to the country's gross national income. Results: A total of 47 articles were included, resulting in 93 cases. The etiological agent was described in 86 (92.5%) patients. Bacteria were the most prevalent etiology (73; 84.8%). Amongst bacterial diagnoses, more frequent cases were Mycobacterium tuberculosis (28; 38.4%); Corynebacterium spp. (15; 20.5%); non-tuberculous mycobacteria (13; 17.8%). The cases were reported in eight different countries, with the USA being the country with the highest number of cases (35; 37.6%). Patients from high-income countries group presented a shorter diagnostic time when compared to low, low-middle, and upper-middle-income countries. A greater number of radiographic studies with pathological findings were described in high-income countries. Conclusion: Non-lactational infectious mastitis is a complex public health problem with diagnostic and treatment challenges. Hence, multi-professional approach-based additional studies are recommended on its epidemiology, diagnosis, treatment, and control.

Plasmodium vivax Gametocytes Adherence to Bone Marrow Endothelial Cells.

In a Plasmodium vivax infection, it was shown a proportionally increased on gametocyte distribution within the bone marrow aspirant, suggesting a role of this organ as a reservoir for this parasite stage. Here, we evaluated the ex vivo cytoadhesive capacity of P. vivax gametocytes to bone marrow endothelial cells (HBMEC) and investigated the involvement of some receptors in the cytoadhesion process by using transfected CHO cells (CHO-ICAM1, CHO-CD36 and CHO-VCAM), wild type (CHO-K1) or deficient in heparan and chondroitin sulfate (CHO-745). Ex-vivo cytoadhesion assays were performed using a total of 44 P. vivax isolates enriched in gametocyte stages by Percoll gradient in the different cell lines. The majority of isolates (88.9%) were able to adhere to HBMEC monolayer. ICAM1 seemed to be the sole receptor significantly involved. CD-36 was the receptor with higher adhesion rate, despite no significance was noticed when compared to CHO-745. We demonstrated that gametocyte P. vivax adheres ex vivo to bone marrow endothelial cells. Moreover, P. vivax gametocytes display the ability to adhere to all CHO cells investigated, especially to CHO-ICAM1. These findings bring insights to the comprehension of the role of the bone marrow as a P. vivax reservoir and the potential impact on parasite transmission to the vector.

Plasmodium vivax metacaspase 1 (PvMCA1) catalytic domain is conserved in field isolates from Brazilian Amazon.

In the present study, we investigated the genetic diversity of Plasmodium vivax metacaspase 1 (PvMCA1) catalytic domain in two municipalities of the main malaria hotspot in Brazil, i.e., the Juruá Valley, and observed complete sequence identity among all P. vivax field isolates and the Sal-1 reference strain. Analysis of PvMCA1 catalytic domain in different P. vivax genomic sequences publicly available also revealed a high degree of conservation worldwide, with very few amino acid substitutions that were not related to putative histidine and cysteine catalytic residues, whose involvement with the active site of protease was herein predicted by molecular modeling. The genetic conservation presented by PvMCA1 may contribute to its eligibility as a druggable target candidate in vivax malaria.

Violacein-Induced Chaperone System Collapse Underlies Multistage Antiplasmodial Activity.

Antimalarial drugs with novel modes of action and wide therapeutic potential are needed to pave the way for malaria eradication. Violacein is a natural compound known for its biological activity against cancer cells and several pathogens, including the malaria parasite, Plasmodium falciparum (Pf). Herein, using chemical genomic profiling (CGP), we found that violacein affects protein homeostasis. Mechanistically, violacein binds Pf chaperones, PfHsp90 and PfHsp70-1, compromising the latter's ATPase and chaperone activities. Additionally, violacein-treated parasites exhibited increased protein unfolding and proteasomal degradation. The uncoupling of the parasite stress response reflects the multistage growth inhibitory effect promoted by violacein. Despite evidence of proteotoxic stress, violacein did not inhibit global protein synthesis via UPR activation-a process that is highly dependent on chaperones, in agreement with the notion of a violacein-induced proteostasis collapse. Our data highlight the importance of a functioning chaperone-proteasome system for parasite development and differentiation. Thus, a violacein-like small molecule might provide a good scaffold for development of a novel probe for examining the molecular chaperone network and/or antiplasmodial drug design.

Transmission-blocking compound candidates against Plasmodium vivax using P. berghei as an initial screening

BACKGROUND Different strategies for improvement of malaria control and elimination are based on the blockage of malaria parasite transmission to the mosquito vector. These strategies include the drugs that target the plasmodial sexual stages in humans and the early developmental stages inside mosquitoes. OBJECTIVES Here we tested Malaria Box compounds in order to evaluate their activity against male and female gametocytes in Plasmodium berghei, mosquito infection in P. vivax and ookinete formation in both species. METHODS/FINDINGS The membrane feeding assay and the development of ookinetes by a 24 h ex vivo culture and the ookinete yield per 1000 erythrocytes were used to test transmission-blocking potential of the Malaria Box compounds in P. vivax. For P. berghei we used flow cytometry to evaluate male and female gametocyte time course and fluorescence microscopy to check the ookinete development. The two species used in this study showed similar results concerning the compounds' activity against gametocytes and ookinetes, which were different from those in P. falciparum. In addition, from the eight Malaria Box compounds tested in both species, compounds MMV665830, MMV665878 and MMV665941 were selected as a hit compounds due the high inhibition observed. CONCLUSION Our results showed that P. berghei is suitable as an initial screening system to test compounds against P. vivax.

Severe tissue complications in patients of Bothrops snakebite at a tertiary health unit in the Brazilian Amazon: clinical characteristics and associated factors

Abstract INTRODUCTION: Snakebites in the Brazilian Amazon are caused mostly by snakes from the Bothrops genus and envenomated patients may suffer from tissue complications. METHODS: This study aimed to identify risk factors for severe tissue complications (STC) in patients with Bothrops snakebite in the Amazonas state, Brazil. RESULTS: Snakebites that were classified as severe and affected female patients with comorbidities presented greater risks of developing STCs. In addition, hospitalizations of patients with STC exceeded 5 days. CONCLUSIONS: Clinical and epidemiological characteristics can prove essential for assessing the evolution of STC and clinical prognosis of patients with Bothrops snakebites.

Pathological findings and morphologic correlation of the lungs of autopsied patients with SARS-CoV-2 infection in the Brazilian Amazon using transmission electron microscopy

Abstract INTRODUCTION: Electron microscopy (EM) is a rapid and effective tool that can be used to create images of a whole spectrum of virus-host interactions and, as such, has long been used in the discovery and description of viral mechanisms. METHODS: Electron microscopy was used to evaluate the pulmonary pathologies of postmortem lung sections from three patients who died from infection with SARS-associated coronavirus 2 (SARS-CoV-2), a new member of the Coronaviridae family. RESULTS: Diffuse alveolar damage (DAD) was predominant in all three patients. The early exudative stage was characterized principally by edema and extravasation of red blood cells into the alveolar space with injury to the alveolar epithelial cells; this was followed by detachment, apoptosis, and necrosis of type I and II pneumocytes. The capillaries exhibited congestion, exposure of the basement membrane from denuded endothelial cells, platelet adhesion, fibrin thrombi, and rupture of the capillary walls. The proliferative stage was characterized by pronounced proliferation of type II alveolar pneumocytes and multinucleated giant cells. The cytopathic effect of SARS-CoV-2 was observed both in degenerated type II pneumocytes and freely circulating in the alveoli, with components from virions, macrophages, lymphocytes, and cellular debris. CONCLUSIONS: Viral particles consistent with the characteristics of SARS-CoV-2 were observed mainly in degenerated pneumocytes, in the endothelium, or freely circulating in the alveoli. In the final stage of illness, the alveolar spaces were replaced by fibrosis.