Epidemiology of chronic kidney disease in older indigenous peoples of Brazil: findings from a cross-sectional survey.

BACKGROUND: Chronic kidney disease (CKD) is a prevalent disease worldwide, with increasing incidence particularly in low- and middle-income countries. Indigenous communities have poorer CKD outcomes due to limited access to healthcare. They are also experiencing a shift toward a sedentary lifestyle and urbanization-related dietary changes, increasing the risk of CKD-related risk factors. AIM: To determine the prevalence of CKD in older Brazilian indigenous and identify the main associated risk factors. METHODS: This cross-sectional study analyzed demographic and clinical data of 229 older indigenous individuals aged 60 years and above in 2022-2023. CKD was defined as an estimated glomerular filtration rate < 60 mL/min/1.73 m2 or a urinary albumin-creatinine ratio > 30 mg/g. Data were presented categorically and analyzed using the Chi-square test or Fisher's exact test. RESULTS: The prevalence of CKD in the population was 26.6%, with higher prevalence in women and increasing with age. The prevalence of hypertension and diabetes was 67.7% and 24.0%, respectively, and these comorbidities were associated with CKD: hypertension (OR = 5.12; 95% CI 2.2-11.9) and diabetes (OR = 5.5; 95% CI 3.7-8.2). No association was found between the prevalence of CKD and obesity, dyslipidemia, cardiovascular disease, or smoking. DISCUSSION: The study found a higher prevalence of CKD among older indigenous populations in Brazil compared to non-indigenous populations, which is exacerbated by risk factors, such as aging, hypertension, diabetes, and lifestyle changes, emphasizing the importance of early detection and intervention in these communities. CONCLUSION: Older persons' indigenous individuals have a high prevalence of CKD, which is correlated with factors, such as sex, age, diabetes mellitus, and hypertension.

Urbanization and kidney dysfunction in Brazilian indigenous people: a burden for the youth

SUMMARY OBJECTIVE: The aim of this study was to investigate whether the degree of urbanization influences the prevalence of chronic kidney disease in Brazilian indigenous people. METHODS: This is a cross-sectional study conducted between 2016 and 2017 in northeastern Brazil and includes individuals aged between 30 and 70 years from two specific indigenous groups who volunteered to participate in the study: the Fulni-ô people (lowest degree of urbanization) and the Truká group (greater degree of urbanization). Cultural and geographical parameters were used to characterize and measure the magnitude of urbanization. We excluded individuals with known cardiovascular disease or renal failure who required hemodialysis. Chronic kidney disease was defined as a single measurement of an estimated glomerular filtration rate <60 mL/min/1.73 m2 using the Chronic Kidney Disease Epidemiology Collaboration creatinine equation. RESULTS: A total of 184 indigenous people from the Fulni-ô group and 96 from the Truká group with a median age of 46 years (interquartile range: 15.2) were included. We found a chronic kidney disease rate of 4.3% in the total indigenous population, generally affecting an older population: 41.7% over 60 years old (p<0.001). The Truká people had a chronic kidney disease prevalence of 6.2%, with no differences in kidney dysfunction across age groups. The Fulni-ô participants had a chronic kidney disease prevalence of 3.3%, with a higher proportion of kidney dysfunction in older participants (of the six Fulni-ô indigenous people with chronic kidney disease, five were older). CONCLUSION: Our results suggest that a higher degree of urbanization seems to negatively influence the prevalence of chronic kidney disease in Brazilian indigenous people.

Prediabetes Induces More Severe Acute COVID-19 Associated With IL-6 Production Without Worsening Long-Term Symptoms.

Aims: Pre-existing conditions, such as age, hypertension, obesity, and diabetes, constitute known risk factors for severe COVID-19. However, the impact of prediabetes mellitus (PDM) on COVID-19 severity is less clear. This study aimed to evaluate the influence of PDM in the acute and long-term phases of COVID-19. Materials and methods: We compared inflammatory mediators, laboratory and clinical parameters and symptoms in COVID-19 patients with prediabetes (PDM) and without diabetes (NDM) during the acute phase of infection and at three months post-hospitalization. Results: Patients with PDM had longer hospital stays and required intensive care unit admission more frequently than NDM. Upon hospitalization, PDM patients exhibited higher serum levels of interleukin 6 (IL-6), which is related to reduced partial pressure of oxygen (PaO2) in arterial blood, oxygen saturation (SpO2) and increased COVID-19 severity. However, at three months after discharge, those with PDM did not exhibit significant alterations in laboratory parameters or residual symptoms; however, PDM was observed to influence the profile of reported symptoms. Conclusions: PDM seems to be associated with increased risk of severe COVID-19, as well as higher serum levels of IL-6, which may constitute a potential biomarker of severe COVID-19 risk in affected patients. Furthermore, while PDM correlated with more severe acute-phase COVID-19, no long-term worsening of sequelae was observed.

Métodos para avaliação da efetividade de vacinas para COVID-19 com ênfase em abordagens quase-experimentais / Methods to evaluate COVID-19 vaccine effectiveness, with an emphasis on quasi-experimental approaches

Resumo A avalição da efetividade de vacinas é feita com dados do mundo real e é essencial para monitorar o desempenho dos programas de vacinação ao longo do tempo bem como frente a novas variantes. Até o momento, a avaliação da efetividade das vacinas para COVID-19 tem sido baseada em métodos clássicos como estudos de coorte e caso controle teste-negativo, que muitas vezes podem não permitir o adequado controle dos vieses intrínsecos da alocação das campanhas de vacinação. O objetivo dessa revisão foi discutir os desenhos de estudo disponíveis para avaliação de efetividade das vacinas, enfatizando os estudos quase-experimentais, que buscam mimetizar os estudos aleatorizados ao introduzir um componente exógeno para atribuição ao tratamento, bem como suas vantagens, limitações e aplicabilidade no contexto dos dados brasileiros. O emprego de métodos quase-experimentais, incluindo as séries temporais interrompidas, o método de diferença em diferenças, escore de propensão, variáveis instrumentais e regressão descontínua, são relevantes pela possibilidade de gerar estimativas mais acuradas da efetividade de vacinas para COVID-19 em cenários como o brasileiro, que se caracteriza pelo uso de várias vacinas, com respectivos número e intervalos entre doses, aplicadas em diferentes faixas etárias e em diferentes momentos da pandemia.

Abstract The evaluation of vaccine effectiveness is conducted with real-world data. They are essential to monitor the performance of vaccination programmes over time, and in the context of the emergence of new variants. Until now, the effectiveness of COVID-19 vaccines has been assessed based on classic methods, such as cohort and test-negative case-control studies, which may often not allow for adequate control of inherent biases in the assignment of vaccination campaigns. The aim of this review was to discuss the study designs available to evaluate vaccine effectiveness, highlighting quasi-experimental studies, which seek to mimic randomized trials, by introducing an exogenous component to allocate to treatment, in addition to the advantages, limitations, and applicability in the context of Brazilian data. The use of quasi-experimental approaches, such as interrupted time series, difference-in-differences, propensity scores, instrumental variables, and regression discontinuity design, are relevant due to the possibility of providing more accurate estimates of COVID-19 vaccine effectiveness. This is especially important in scenarios such as the Brazilian, which characterized by the use of various vaccines, with the respective numbers and intervals between doses, applied to different age groups, and introduced at different times during the pandemic.

A Double-blind, Randomized Trial to Evaluate Miltefosine and Topical Granulocyte Macrophage Colony-stimulating Factor in the Treatment of Cutaneous Leishmaniasis Caused by Leishmania braziliensis in Brazil.

BACKGROUND: The treatment of cutaneous leishmaniasis (CL) in Brazil using pentavalent antimony (Sbv) is associated with a high rate of failure. Miltefosine has proven efficacy for CL caused by L. braziliensis, with a cure rate (CR) of 75%. A combined treatment with granulocyte macrophage colony-stimulating factor (GM-CSF) and miltefosine could increase CR and decrease healing time. METHODS: A randomized, double-blind clinical trial to evaluate the efficacy of miltefosine combined with topical GM-CSF (M + GM) vs miltefosine and placebo (M + P) vs Sbv in 133 patients with CL caused by L. braziliensis in Bahia, Brazil. RESULTS: The final CR at 180 days after the initiation of treatment was 44.4% in the Sbv group, 76.6% in the M + P group (P = .003 vs Sbv), and 75.6% in the M + GM group (P = .004 vs Sbv). The median healing time for cure was 102 days for the Sbv group and 60 days for both miltefosine groups (P = .0009). During the 6-month follow-up period, 4 relapses were documented: 1 in the Sbv group, 1 in the M + P group, and 2 in the M + GM group. Mild adverse events occurred in 65% of patients from the Sbv group, 76% and 79% from the M + P and M + GM groups respectively. CONCLUSIONS: Miltefosine is more effective than Sbv for the treatment of CL caused by L. braziliensis in Brazil and accelerates the healing time. Association with GM-CSF does not improve therapeutic outcome. CLINICAL TRIALS REGISTRATION: NCT03023111.

Association of miltefosine with granulocyte and macrophage colony-stimulating factor (GM-CSF) in the treatment of cutaneous leishmaniasis in the Amazon region: A randomized and controlled trial.

OBJECTIVES: To compare topical granulocyte and macrophage colony-stimulating factor (GM-CSF) and miltefosine (G + M) versus placebo and miltefosine (P + M) or parenteral meglumine antimoniate (MA) in the treatment of 150 patients with cutaneous leishmaniasis (CL) caused by Leishmania guyanensis in the Amazon. DESIGN: A randomized and double-blinded clinical trial. RESULTS: At 90 days after the initiation of therapy, the cure rates were 66%, 58%, and 52% for the groups P + M, G + M, and MA, respectively (p > 0.05). Cure rates at 180 days did not differ. Healing time was similar in the 3 groups, but faster in the MA group as compared to the G + M group (p = 0.04). Mild and transitory systemic adverse events were frequent in all groups (above 85%). Nausea (85%) and vomiting (39%) predominated in the miltefosine groups and arthralgia (51%) and myalgia (48%) in the MA group. One patient (group MA) stopped treatment after presenting with fever, exanthema, and severe arthralgia. CONCLUSIONS: Miltefosine did not present a higher cure rate than MA, and the association of GM-CSF did not improve the therapeutic response. Nevertheless, because of its less toxicity, easier administration, and a similar cure rate when compared with MA, miltefosine should remain as one of the main drugs for treating CL due to L. guyanensis. (Clinicaltrials.gov Identifier NCT03023111).

Ecocardiografia e Análise de Doenças Cardiovasculares Subclínicas em Povos Indígenas que Vivem em Diferentes Graus de Urbanização: Projeto de Aterosclerose nas Populações Indígenas (Pai) / Echocardiography and Analysis of Subclinical Cardiovascular Diseases in Indigenous People Living in Different Degrees of Urbanization: Project of Atherosclerosis Among Indigenous Populations (Pai

Fundamento: O processo de urbanização tem impacto na carga de doenças cardiovasculares. As populações indígenas podem sofrer uma transição epidemiológica devastadora. Objetivos: Descrever o protocolo de estudo do Projeto de Aterosclerose nas Populações Indígenas (PAI) para avaliar a análise ecocardiográfica e as doenças cardiovasculares (CV) subclínicas em populações indígenas de acordo com o grau de urbanização e mostrar resultados preliminares do estudo piloto. Métodos: O PAI é um estudo transversal, com voluntários com idade entre 30 e 70 anos, em grupos indígenas brasileiros expostos a estágios baixos e avançados de urbanização (Fulni-ô e Truká, respectivamente) e um grupo controle urbano, excluindo indivíduos com doenças CV conhecidas ou em hemodiálise. O estudo piloto começou no território de Fulni-ô em setembro de 2016. Os participantes foram submetidos a avaliação clínica e laboratorial, eletrocardiograma (ECG), ultrassonografia de carótidas e um protocolo ecocardiográfico abrangente, incluindo strain longitudinal global (SLG) avaliado por speckle tracking. Os resultados preliminares são descritos de acordo com o sexo em uma análise univariada. Resultados: O estudo piloto avaliou o protocolo descrito em 55 indivíduos do grupo indígena Fulni-ô (48,7 ± 12,0 anos, 80% mulheres). Foram encontrados fatores de risco tradicionais como hipertensão, diabetes e dislipidemia em 40%, 36% e 54%, respectivamente, sem diferenças estatísticas significativas entre os sexos. O uso de tabaco mostrou-se extremamente prevalente, referido em 91% dos participantes. Os parâmetros derivados da ecocardiografia estavam, em média, dentro da faixa normal. No entanto, a média do SLG foi de 17,3 ± 3,4% (p 0,73 por sexo). Conclusão: Descrevemos o protocolo do estudo PAI para avaliar doenças cardiovasculares subclínicas e fatores de risco em populações indígenas de acordo com o estágio de urbanização. Resultados preliminares sugerem alta prevalência desses na população indígena em menor grau de urbanização.

Background: The urbanization process impacts the burden of cardiovascular disease (CVD). Indigenous populations can undergo a devastating epidemiological transition. Objective: The present study aimed to describe the Project of Atherosclerosis among Indigenous Populations (PAI) study protocol for assessing echocardiographic images and subclinical CVD in indigenous populations according to the degree of urbanization and report its preliminary results. Methods: The PAI is a cross-sectional study that includes volunteers aged 30­70 years among Brazilian indigenous groups exposed to low and advanced stages of urbanization (Fulni-ô and Truká, respectively) and an urban control group. Individuals with known CVD or who were on hemodialysis were excluded. The pilot study began in Fulni-ô territory in September 2016. The participants underwent clinical and laboratory

Evaluation of the Ability of Miltefosine Associated with Topical GM-CSF in Modulating the Immune Response of Patients with Cutaneous Leishmaniasis.

Cutaneous leishmaniasis (CL) due to L. braziliensis is associated with an exaggerated inflammatory response and tissue damage. Miltefosine is more effective than pentavalent antimony (Sbv) in the treatment of CL, and here, we evaluate the ability of Sbv, miltefosine, and GM-CSF administered intravenously, orally, or topically, respectively, to modify the immune response. Patients were treated with miltefosine plus GM-CSF, miltefosine plus placebo, or Sbv. Mononuclear cells were stimulated with soluble Leishmania antigen (SLA) on day 0 and day 15 of therapy, and cytokine levels were determined in supernatants by ELISA. The lymphocyte proliferation and oxidative burst were evaluated by flow cytometry, and the degree of infection and Leishmania killing by optical microscopy. Proliferation of CD4+ T cells were enhanced in patients using miltefosine and in CD8+ T cells when GM-CSF was associated. Enhancement in the oxidative burst occurred in the miltefosine plus GM-CSF group on day 15 of therapy. Moreover, the number of L. braziliensis in infected monocytes on day 15 as well as the percentage of infected cells was lower after 48- and 72-hour culture in cells from patients treated with miltefosine plus GM-CSF. In addition to the ability of miltefosine to kill Leishmania, the changes in the immune response caused by miltefosine and GM-CSF may increase the cure rate of CL patients using these drugs.

Investigating associations between intestinal alterations and parasite load according to Bifidobacterium spp. and Lactobacillus spp. abundance in the gut microbiota of hamsters infected by Leishmania infantum

BACKGROUND Visceral leishmaniasis (VL) is a tropical neglected disease with high associated rates of mortality. Several studies have highlighted the importance of the intestinal tract (IT) and gut microbiota (GM) in the host immunological defense. Data in the literature on parasite life cycle and host immune defense against VL are scarce regarding the effects of infection on the IT and GM. OBJECTIVES This study aimed to investigate changes observed in the colon of Leishmania infantum-infected hamsters, including alterations in the enteric nervous system (ENS) and GM (specifically, levels of bifidobacteria and lactobacilli). METHODS Male hamsters were inoculated with L. infantum and euthanised at four or eight months post-infection. Intestines were processed for histological analysis and GM analysis. Quantitative polymerase chain reaction (qPCR) was performed to quantify each group of bacteria: Bifidobacterium spp. (Bf) and Lactobacillus spp (LacB). FINDINGS Infected hamsters showed histoarchitectural loss in the colon wall, with increased thickness in the submucosa and the mucosa layer, as well as greater numbers of intraepithelial lymphocytes. Forms suggestive of amastigotes were seen inside mononuclear cells. L. infantum infection induced changes in ENS, as evidenced by increases in the area of colonic enteric ganglia. Despite the absence of changes in the levels of Bf and LacB during the course of infection, the relative abundance of these bacteria was associated with parasite load and histological alterations. MAIN CONCLUSIONS Our results indicate that L. infantum infection leads to important changes in the colon and suggest that bacteria in the GM play a protective role.

Preservação da privacidade no enfrentamento da COVID-19: dados pessoais e a pandemia global / Personal data usage and privacy considerations in the COVID-19 global pandemic

Resumo Dados ganham cada vez mais importância e valor na busca de respostas para enfrentar a COVID-19 tanto para a ciência quanto para as autoridades sanitárias. Em virtude da dificuldade de realizar diagnóstico da infecção na população em geral, iniciativas apoiadas em tecnologias digitais vêm sendo desenvolvidas por governos ou empresas privadas para possibilitar rastreamentos de sintomas, contatos e deslocamentos de modo a apoiar estratégias de acompanhamento e avaliação na vigilância de contágios. A despeito da importância e necessidade dessas iniciativas, questionamentos acerca da quantidade e tipos de dados pessoais coletados, processados, compartilhados e utilizados em nome da saúde pública, bem como os concomitantes ou posteriores usos desses dados, suscitam questionamentos éticos, legais e técnicos. Desafios que apontam para a necessidade de novos modelos de governança de dados e de tecnologias, responsáveis e transparentes, para controlar o Sars-Cov2 e as futuras emergências de saúde pública.

Abstract Data has become increasingly important and valuable for both scientists and health authorities searching for answers to the COVID-19 crisis. Due to difficulties in diagnosing this infection in populations around the world, initiatives supported by digital technologies are being developed by governments and private companies to enable the tracking of the public's symptoms, contacts and movements. Considering the current scenario, initiatives designed to support infection surveillance and monitoring are essential and necessary. Nonetheless, ethical, legal and technical questions abound regarding the amount and types of personal data being collected, processed, shared and used in the name of public health, as well as the concomitant or posterior use of this data. These challenges demonstrate the need for new models of responsible and transparent data and technology governance in efforts to control SARS-COV2, as well as in future public health emergencies.

Urbanization is Associated with Increased Trends in Cardiovascular Mortality Among Indigenous Populations: the PAI Study / Urbanização Associa-se com Tendência a Maior Mortalidade Cardiovascular em Populações Indígenas: o Estudo PAI

Abstract Background: The cardiovascular risk burden among diverse indigenous populations is not totally known and may be influenced by lifestyle changes related to the urbanization process. Objectives: To investigate the cardiovascular (CV) mortality profile of indigenous populations during a rapid urbanization process largely influenced by governmental infrastructure interventions in Northeast Brazil. Methods: We assessed the mortality of indigenous populations (≥ 30 y/o) from 2007 to 2011 in Northeast Brazil (Bahia and Pernambuco states). Cardiovascular mortality was considered if the cause of death was in the ICD-10 CV disease group or if registered as sudden death. The indigenous populations were then divided into two groups according to the degree of urbanization based on anthropological criteria:9,10 Group 1 - less urbanized tribes (Funi-ô, Pankararu, Kiriri, and Pankararé); and Group 2 - more urbanized tribes (Tuxá, Truká, and Tumbalalá). Mortality rates of highly urbanized cities (Petrolina and Juazeiro) in the proximity of indigenous areas were also evaluated. The analysis explored trends in the percentage of CV mortality for each studied population. Statistical significance was established for p value < 0.05. Results: There were 1,333 indigenous deaths in tribes of Bahia and Pernambuco (2007-2011): 281 in Group 1 (1.8% of the 2012 group population) and 73 in Group 2 (3.7% of the 2012 group population), CV mortality of 24% and 37%, respectively (p = 0.02). In 2007-2009, there were 133 deaths in Group 1 and 44 in Group 2, CV mortality of 23% and 34%, respectively. In 2009-2010, there were 148 deaths in Group 1 and 29 in Group 2, CV mortality of 25% and 41%, respectively. Conclusions: Urbanization appears to influence increases in CV mortality of indigenous peoples living in traditional tribes. Lifestyle and environmental changes due to urbanization added to suboptimal health care may increase CV risk in this population.

Resumo Fundamento: O risco cardiovascular das diversas comunidades indígenas não está bem estabelecido e pode ser influenciado pelo processo de urbanização a que se submetem esses povos. Objetivos: Investigar o perfil da mortalidade cardiovascular (CV) das populações indígenas durante o rápido processo de urbanização altamente influenciado por intervenções governamentais de infraestrutura no Nordeste do Brasil. Métodos: Avaliamos a mortalidade de populações indígenas (≥ 30 anos) do Vale do São Francisco (Bahia e Pernambuco) no período de 2007-2011. Considerou-se mortalidade CV se a causa de morte constasse no grupo de doenças CV do CID-10 ou se tivesse sido registrada como morte súbita. As populações indígenas foram divididas em dois grupos conforme o grau de urbanização baseado em critérios antropológicos: Grupo 1 - menos urbanizadas (Funi-ô, Pankararu, Kiriri e Pankararé); e Grupo 2 - mais urbanizadas (Tuxá, Truká e Tumbalalá). Taxas de mortalidade de cidades altamente urbanizadas (Petrolina e Juazeiro) nas proximidades das áreas indígenas foram também avaliadas. A análise explorou tendências na porcentagem de mortalidade CV para cada população estudada. Adotou-se o valor de p < 0,05 como significância estatística. Resultados: Houve 1.333 mortes indígenas nas tribos da Bahia e de Pernambuco (2007-2011): 281 no Grupo 1 (1,8% da população de 2012) e 73 no Grupo 2 (3,7% da população de 2012), mortalidade CV de 24% e 37%, respectivamente (p = 0,02). Entre 2007 e 2009, houve 133 mortes no Grupo 1 e 44 no Grupo 2, mortalidade CV de 23% e 34%, respectivamente. Entre 2009 e 2010, houve 148 mortes no Grupo 1 e 29 no Grupo 2, mortalidade CV de 25% e 41%, respectivamente. Conclusões: A urbanização parece influenciar os aumentos de mortalidade CV dos povos indígenas vivendo de modo tradicional. Mudanças no estilo de vida e ambientais devidas à urbanização somadas à subótima atenção à saúde podem estar implicadas no aumento do risco CV nos povos indígenas.

G Protein-Coupled Kinin Receptors and Immunity Against Pathogens.

For decades, immunologists have considered the complement system as a paradigm of a proteolytic cascade that, acting cooperatively with the immune system, enhances host defense against infectious organisms. In recent years, advances made in thrombosis research disclosed a functional link between activated neutrophils, monocytes, and platelet-driven thrombogenesis. Forging a physical barrier, the fibrin scaffolds generated by synergism between the extrinsic and intrinsic (contact) pathways of coagulation entrap microbes within microvessels, limiting the systemic spread of infection while enhancing the clearance of pathogens by activated leukocytes. Insight from mice models of thrombosis linked fibrin formation via the intrinsic pathway to the autoactivation of factor XII (FXII) by negatively charged "contact" substances, such as platelet-derived polyphosphates and DNA from neutrophil extracellular traps. Following cleavage by FXIIa, activated plasma kallikrein (PK) initiates inflammation by liberating the nonapeptide bradykinin (BK) from an internal domain of high molecular weight kininogen (HK). Acting as a paracrine mediator, BK induces vasodilation and increases microvascular permeability via activation of endothelial B2R, a constitutively expressed subtype of kinin receptor. During infection, neutrophil-driven extravasation of plasma fuels inflammation via extravascular activation of the kallikrein-kinin system (KKS). Whether liberated by plasma-borne PK, tissue kallikrein, and/or microbial-derived proteases, the short-lived kinins activate immature dendritic cells via B2R, thus linking the infection-associated innate immunity/inflammation to the adaptive arm of immunity. As inflammation persists, a GPI-linked carboxypeptidase M removes the C-terminal arginine from the primary kinin, converting the B2R agonist into a high-affinity ligand for B1R, a GPCR subtype that is transcriptionally upregulated in injured/inflamed tissues. As reviewed here, lessons taken from studies of kinin receptor function in experimental infections have shed light on the complex proteolytic circuits that, acting at the endothelial interface, reciprocally couple immunity to the proinflammatory KKS.

Scoring clinical signs can help diagnose canine visceral leishmaniasis in a highly endemic area in Brazil

Canine visceral leishmaniasis (CVL) diagnosis is still a challenge in endemic areas with limited diagnostic resources. This study proposes a score with the potential to distinguish positive CVL cases from negative ones. We studied 265 dogs that tested positive for CVL on ELISA and parasitological tests. A score ranging between 0 and 19 was recorded on the basis of clinical signs. Dogs with CVL had an overall higher positivity of the majority of clinical signs than did dogs without CVL or with ehrlichiosis. Clinical signs such as enlarged lymph nodes (83.93%), muzzle/ear lesions (55.36%), nutritional status (51.79%), bristle condition (57.14%), pale mucosal colour (48.21%), onychogryphosis (58.93%), skin lesion (39.28%), bleeding (12.50%), muzzle depigmentation (41.07%), alopecia (39.29%), blepharitis (21.43%), and keratoconjunctivitis (42.86%) were more frequent in dogs with CVL than in dogs with ehrlichiosis or without CVL. Moreover, the clinical score increased according to the positivity of all diagnostic tests (ELISA, p < 0.001; parasite culture, p = 0.0021; and smear, p = 0.0003). Onychogryphosis (long nails) [odds ratio (OR): 3.529; 95% confidence interval (CI): 1.832-6.796; p < 0.001], muzzle depigmentation (OR: 4.651; 95% CI: 2.218-9.750; p < 0.001), and keratoconjunctivitis (OR: 5.400; 95% CI: 2.549-11.441; p < 0.001) were highly associated with CVL. Interestingly, a score cut-off value ≥ 6 had an area under the curve of 0.717 (p < 0.0001), sensitivity of 60.71%, and specificity of 73.64% for CVL diagnosis. The clinical sign-based score for CVL diagnosis suggested herein can help veterinarians reliably identify dogs with CVL in endemic areas with limited diagnostic resources.

Gene Expression Profile of High IFN-γ Producers Stimulated with Leishmania braziliensis Identifies Genes Associated with Cutaneous Leishmaniasis.

BACKGROUND: The initial response to Leishmania parasites is essential in determining disease development or resistance. In vitro, a divergent response to Leishmania, characterized by high or low IFN-γ production has been described as a potential tool to predict both vaccine response and disease susceptibility in vivo. METHODS AND FINDINGS: We identified uninfected and healthy individuals that were shown to be either high- or low IFN-γ producers (HPs and LPs, respectively) following stimulation of peripheral blood cells with Leishmania braziliensis. Following stimulation, RNA was processed for gene expression analysis using immune gene arrays. Both HPs and LPs were shown to upregulate the expression of CXCL10, IFI27, IL6 and LTA. Genes expressed in HPs only (CCL7, IL8, IFI44L and IL1B) were associated with pathways related to IL17 and TREM 1 signaling. In LPs, uniquely expressed genes (for example IL9, IFI44, IFIT1 and IL2RA) were associated with pathways related to pattern recognition receptors and interferon signaling. We then investigated whether the unique gene expression profiles described here could be recapitulated in vivo, in individuals with active Cutaneous Leishmaniasis or with subclinical infection. Indeed, using a set of six genes (TLR2, JAK2, IFI27, IFIT1, IRF1 and IL6) modulated in HPs and LPs, we could successfully discriminate these two clinical groups. Finally, we demonstrate that these six genes are significantly overexpressed in CL lesions. CONCLUSION: Upon interrogation of the peripheral response of naive individuals with diverging IFN-γ production to L. braziliensis, we identified differences in the innate response to the parasite that are recapitulated in vivo and that discriminate CL patients from individuals presenting a subclinical infection.

The microbiological signature of human cutaneous leishmaniasis lesions exhibits restricted bacterial diversity compared to healthy skin

Localised cutaneous leishmaniasis (LCL) is the most common form of cutaneous leishmaniasis characterised by single or multiple painless chronic ulcers, which commonly presents with secondary bacterial infection. Previous culture-based studies have found staphylococci, streptococci, and opportunistic pathogenic bacteria in LCL lesions, but there have been no comparisons to normal skin. In addition, this approach has strong bias for determining bacterial composition. The present study tested the hypothesis that bacterial communities in LCL lesions differ from those found on healthy skin (HS). Using a high throughput amplicon sequencing approach, which allows for better populational evaluation due to greater depth coverage and the Quantitative Insights Into Microbial Ecology pipeline, we compared the microbiological signature of LCL lesions with that of contralateral HS from the same individuals.Streptococcus, Staphylococcus,Fusobacterium and other strict or facultative anaerobic bacteria composed the LCL microbiome. Aerobic and facultative anaerobic bacteria found in HS, including environmental bacteria, were significantly decreased in LCL lesions (p < 0.01). This paper presents the first comprehensive microbiome identification from LCL lesions with next generation sequence methodology and shows a marked reduction of bacterial diversity in the lesions.

Degranulating Neutrophils Promote Leukotriene B4 Production by Infected Macrophages To Kill Leishmania amazonensis Parasites.

Neutrophils mediate early responses against pathogens, and they become activated during endothelial transmigration toward the inflammatory site. In the current study, human neutrophils were activated in vitro with immobilized extracellular matrix proteins, such as fibronectin (FN), collagen, and laminin. Neutrophil activation by FN, but not other extracellular matrix proteins, induces the release of the granules' contents, measured as matrix metalloproteinase 9 and neutrophil elastase activity in culture supernatant, as well as reactive oxygen species production. Upon contact with Leishmania amazonensis-infected macrophages, these FN-activated neutrophils reduce the parasite burden through a mechanism independent of cell contact. The release of granule proteases, such as myeloperoxidase, neutrophil elastase, and matrix metalloproteinase 9, activates macrophages through TLRs, leading to the production of inflammatory mediators, TNF-α and leukotriene B4 (LTB4), which are involved in parasite killing by infected macrophages. The pharmacological inhibition of degranulation reverted this effect, abolishing LTB4 and TNF production. Together, these results suggest that FN-driven degranulation of neutrophils induces the production of LTB4 and TNF by infected macrophages, leading to the control of Leishmania infection.

Immunoregulation in human malaria: the challenge of understanding asymptomatic infection

Asymptomatic Plasmodium infection carriers represent a major threat to malaria control worldwide as they are silent natural reservoirs and do not seek medical care. There are no standard criteria for asymptomaticPlasmodium infection; therefore, its diagnosis relies on the presence of the parasite during a specific period of symptomless infection. The antiparasitic immune response can result in reducedPlasmodium sp. load with control of disease manifestations, which leads to asymptomatic infection. Both the innate and adaptive immune responses seem to play major roles in asymptomatic Plasmodiuminfection; T regulatory cell activity (through the production of interleukin-10 and transforming growth factor-β) and B-cells (with a broad antibody response) both play prominent roles. Furthermore, molecules involved in the haem detoxification pathway (such as haptoglobin and haeme oxygenase-1) and iron metabolism (ferritin and activated c-Jun N-terminal kinase) have emerged in recent years as potential biomarkers and thus are helping to unravel the immune response underlying asymptomatic Plasmodium infection. The acquisition of large data sets and the use of robust statistical tools, including network analysis, associated with well-designed malaria studies will likely help elucidate the immune mechanisms responsible for asymptomatic infection.

Medical Specialty Choice and Related Factors of Brazilian Medical Students and Recent Doctors.

BACKGROUND: Choosing a medical specialty is an important, complex, and not fully understood process. The present study investigated the factors that are related to choosing and rejecting medical specialties in a group of students and recent medical doctors. METHODOLOGY AND FINDINGS: A cross-sectional survey of 1,223 medical students and doctors was performed in Brazil in 2012. A standardized literature-based questionnaire was applied that gathered preferable or rejected specialties, and asked questions about extracurricular experiences and the influence of 14 factors on a Likert-type scale from 0 to 4. Specialties were grouped according to lifestyle categories: controllable and uncontrollable, which were subdivided into primary care, internal medicine, and surgical specialties. Notably, the time period of rejection was usually earlier than the time period of intended choice (p < 0.0001, χ(2) = 107.2). The choice mainly occurred during the internship period in medical school (n = 466; 38.7%). An overall large frequency of participation in extracurricular activities was observed (n = 1,184; 95.8%), which were highly associated with the respective medical area. Orthopedic surgery had the highest correlation with participation in specialty-specific organized groups (OR = 59.9, 95% CI = 21.6-166.3) and psychiatry was correlated with participation in research groups (OR = 18.0, 95% CI = 9.0-36.2). With regard to influential factors in controllable lifestyle specialties, "financial reason" (mean score ± standard deviation: 2.8 ± 1.0; median = 3) and "personal time" (3.1 ± 1.3; median = 4) were important factors. In primary care, these factors were less important (1.7 ± 1.3 and 1.7 ± 1.5, respectively; median = 2 for both), and higher scores were observed for "curricular internship" (3.2 ± 1.1, median = 4) and "social commitment" (2.6 ± 1.3, median = 3). CONCLUSION: The present findings provide important insights into developing strategies to stimulate interest in specialties based on the needs of the Brazilian healthcare system.

Prediction of CD8+ Epitopes in Leishmania braziliensis Proteins Using EPIBOT: In Silico Search and In Vivo Validation.

BACKGROUND: Leishmaniasis is caused by intracellular Leishmania parasites that induce a T-cell mediated response associated with recognition of CD4+ and CD8+ T cell Line 1Lineepitopes. Identification of CD8+ antigenic determinants is crucial for vaccine and therapy development. Herein, we developed an open-source software dedicated to search and compile data obtained from currently available on line prediction algorithms. METHODOLOGY/PRINCIPAL FINDINGS: We developed a two-phase algorithm and implemented in an open source software called EPIBOT, that consolidates the results obtained with single prediction algorithms, generating a final output in which epitopes are ranked. EPIBOT was initially trained using a set of 831 known epitopes from 397 proteins from IEDB. We then screened 63 Leishmania braziliensis vaccine candidates with the EPIBOT trained tool to search for CD8+ T cell epitopes. A proof-of-concept experiment was conducted with the top eight CD8+ epitopes, elected by EPIBOT. To do this, the elected peptides were synthesized and validated for their in vivo cytotoxicity. Among the tested epitopes, three were able to induce lysis of pulsed-target cells. CONCLUSION: Our results show that EPIBOT can successfully search across existing prediction tools, generating a compiled list of candidate CD8+ epitopes. This software is fast and a simple search engine that can be customized to search over different MHC alleles or HLA haplotypes.