Genetic variability of Leishmania (Leishmania) infantum causing human visceral leishmaniasis in the Southeastern Brazil.

Leishmania infantum is a protozoan that causes visceral leishmaniasis (VL) in the Americas and some regions of Europe. The disease is mainly characterized by hepatosplenomegaly and fever, and can be fatal. Factors related to the host and parasite can contribute to the transmission of Leishmania and the clinical outcome. The intraspecific genetic variability of L. infantum strains may be one of these factors. In this study, we evaluated the genetic variability of L. infantum obtained from bone marrow smear slides from patients in the Sao Paulo State, Brazil. For this, the minicircle of the kDNA hypervariable region was used as target by Sanger sequencing. By analyzing the similarity of the nucleotides and the maximum likelihood tree (Fasttree), we observed a high similarity (98%) among samples. Moreover, we identified four different profiles of L. infantum. In conclusion, L. infantum strains from Sao Paulo State, Brazil, showed low diversity measured by minicircle of the kDNA hypervariable region.

Genetic variability of Leishmania (Leishmania) infantum causing human visceral leishmaniasis in the Southeastern Brazil

ABSTRACT Leishmania infantum is a protozoan that causes visceral leishmaniasis (VL) in the Americas and some regions of Europe. The disease is mainly characterized by hepatosplenomegaly and fever, and can be fatal. Factors related to the host and parasite can contribute to the transmission of Leishmania and the clinical outcome. The intraspecific genetic variability of L. infantum strains may be one of these factors. In this study, we evaluated the genetic variability of L. infantum obtained from bone marrow smear slides from patients in the Sao Paulo State, Brazil. For this, the minicircle of the kDNA hypervariable region was used as target by Sanger sequencing. By analyzing the similarity of the nucleotides and the maximum likelihood tree (Fasttree), we observed a high similarity (98%) among samples. Moreover, we identified four different profiles of L. infantum. In conclusion, L. infantum strains from Sao Paulo State, Brazil, showed low diversity measured by minicircle of the kDNA hypervariable region.

Micro-Fourier-transform infrared reflectance spectroscopy as tool for probing IgG glycosylation in COVID-19 patients.

It has been reported that patients diagnosed with COVID-19 become critically ill primarily around the time of activation of the adaptive immune response. However the role of antibodies in the worsening of disease is not obvious. Higher titers of anti-spike immunoglobulin IgG1 associated with low fucosylation of the antibody Fc tail have been associated to excessive inflammatory response. In contrast it has been also reported that NP-, S-, RBD- specific IgA, IgG, and IgM are not associated with SARS-CoV-2 viral load, indicating that there is no obvious correlation between antibody response and viral antigen detection. In the present work the micro-Fourier-transform infrared reflectance spectroscopy (micro-FTIR) was employed to investigate blood serum samples of healthy and COVID-19-ill (mild or oligosymptomatic) individuals (82 healthcare workers volunteers in "Instituto de Infectologia Emilio Ribas", São Paulo, Brazil). The molecular-level-sensitive, multiplexing quantitative and qualitative FTIR data probed on 1 µL of dried biofluid was compared to signal-to-cutoff index of chemiluminescent immunoassays CLIA and ELISA (IgG antibodies against SARS-CoV-2). Our main result indicated that 1702-1785 [Formula: see text] spectral window (carbonyl C=O vibration) is a spectral marker of the degree of IgG glycosylation, allowing to probe distinctive sub-populations of COVID-19 patients, depending on their degree of severity. The specificity was 87.5 % while the detection rate of true positive was 100%. The computed area under the receiver operating curve was equivalent to CLIA, ELISA and other ATR-FTIR methods ([Formula: see text]). In summary, overall discrimination of healthy and COVID-19 individuals and severity prediction as well could be potentially implemented using micro-FTIR reflectance spectroscopy on blood serum samples. Considering the minimal and reagent-free sample preparation procedures combined to fast (few minutes) outcome of FTIR we can state that this technology is suitable for fast screening of immune response of individuals with COVID-19. It would be an important tool in prospective studies, helping investigate the physiology of the asymptomatic, oligosymptomatic, or severe individuals and measure the extension of infection dissemination in patients.

Prevalência de rastreio positivo para síndrome de Cushing em indivíduos obesos candidatos ao tratamento cirúrgico para obesidade / Prevalence of positive screening for Cushing's syndrome in obese indivi-duals who are candidates for bariatric surgery

Introdução: A obesidade afeta mais de um terço dos norte-americanos e sua prevalência está aumentando nos brasileiros. Em casos graves, a cirurgia bariátrica é considerada o tratamento mais bem-sucedido e duradouro. Durante a avaliação pré operatória, deve-se investigar causas secundárias de obesidade e, especificamente no Brasil, deve-se excluir síndrome de Cushing (SC) nesses pacientes, apesar de recomendações controversas de rastreio de SC em diretrizes atuais. A prevalência de SC endógena é extremamente baixa, mas parece ser maior em populações específicas, como pacientes diabéticos, com hipertensão resistente, ou portadores de obesidade Objetivo: Avaliar a prevalência de triagem positiva para SC em obesos candidatos a cirurgia bariátrica e discutir possíveis fatores de risco ou co-morbidades associadas à positividade do rastreio. Material e Métodos: Estudo retrospectivo com 629 pacientes atendidos no ambulatório de obesidade da Santa Casa de Belo Horizonte entre 2008 e 2016. Realizada a triagem da SC com o teste de supressão noturna com 1mg de dexametasona (1mg-DST), dosando o cortisol na manhã seguinte (ponto de corte ≥1,8µg/dL). Resultados: 80 dos 629 pacientes apresentaram rastreio positivo para SC. Destes, 20 pacientes foram considerados negativos após repetirem o 1mg-DST e 6 pacientes foram negativos após o teste Liddle 1. Conclusão: A prevalência de rastreio positivo para SC foi igual a 12,7%, semelhante aos dados da literatura. Nenhum fator de risco ou co-morbidade pôde ser diretamente associado à positividade do teste de rastreamento.

Introduction: Obesity affects more than a third of Americans and its prevalence is increasing in Brazilians. In severe cases, bariatric surgery is considered the most successful and long-lasting treatment. During the preoperative evaluation, secondary causes of obesity should be investigated and, specifically in Brazil, Cushing's Syndrome (CS) should be excluded in these patients, despite controversial recommendations for CS screening in current guidelines. The prevalence of endogenous SC is extremely low, but appears to be higher in specific populations, such as diabetics, patients with resistant hypertension or those with obesity. Aim: To evaluate the prevalence of positive screening for CS in obese candidates for bariatric surgery and to discuss possible risk factors or comorbidities associated with screening positivity. Material and Methods: A retrospective study was conducted with 629 patients attended at the Obesity Outpatient Clinic of Santa Casa, Belo Horizonte between 2008 and 2016. CS screening was performed with a 1mg dexamethasone (1mg-DST) suppression test, dosing cortisol in the next morning (cut-off point ≥1.8µg / dL). Results:80 of the 629 patients had positive screening for SC. Of these, 20 patients were considered negative after repeated 1mg-DST and 6 patients were negative after the Liddle 1 test. Conclusion: The prevalence of positive screening for SC was 12.7%, similar to the literature. No risk factor or co-morbidity could be directly associated with the positivity of the screening test.