Polyunsaturated fatty acids alter the formation of lipid droplets and eicosanoid production in Leishmania promastigotes

BACKGROUND The knowledge about eicosanoid metabolism and lipid droplet (LD) formation in the Leishmania is very limited and new approaches are needed to identify which bioactive molecules are produced of them. OBJECTIVES Herein, we compared LDs and eicosanoids biogenesis in distinct Leishmania species which are etiologic agents of different clinical forms of leishmaniasis. METHODS For this, promastigotes of Leishmania amazonensis, L. braziliensis and L. infantum were stimulated with polyunsaturated fatty acids (PUFA) and LD and eicosanoid production was evaluated. We also compared mutations in structural models of human-like cyclooxygenase-2 (GP63) and prostaglandin F synthase (PGFS) proteins, as well as the levels of these enzymes in parasite cell extracts. FINDINGS PUFAs modulate the LD formation in L. braziliensis and L. infantum. Leishmania spp with equivalent tissue tropism had same protein mutations in GP63 and PGFS. No differences in GP63 production were observed among Leishmania spp, however PGFS production increased during the parasite differentiation. Stimulation with arachidonic acid resulted in elevated production of hydroxyeicosatetraenoic acids compared to prostaglandins. MAIN CONCLUSIONS Our data suggest LD formation and eicosanoid production are distinctly modulated by PUFAS dependent of Leishmania species. In addition, eicosanoid-enzyme mutations are more similar between Leishmania species with same host tropism.

Perfil epidemiológico da tuberculose no município de Barreiras (BA), no período de 2008 a 2018 / Epidemiological profile of tuberculosis in Barreiras (BA) from 2008 to 2018 / Perfil epidemiológico de la tuberculosis en el municipio de Barreiras (Bahía) en el periodo de 2008 a 2018

O objetivo deste estudo foi descrever o perfil epidemiológico da tuberculose em Barreiras (BA) entre 2008 e 2018. Trata-se de um estudo epidemiológico, descritivo, de série histórica, cujos dados foram obtidos no Sistema de Informação de Agravos de Notificação (Sinan), no Sistema de Informação Sobre Mortalidade (SIM) e no Centro de Saúde Leonídia Ayres de Almeida. Foram calculados coeficientes de incidência e de mortalidade. A espacialização da distribuição dos casos por bairros foi elaborada no software ArcGIS 10.2. Nos 537 casos analisados, predominaram homens (57%) de 35-49 anos de idade (26,8%), idosos (> 60 anos) apresentaram incidência e mortalidade superiores à média nacional, e 3,7% dos pacientes estavam coinfectados com o vírus da imunodeficiência humana (HIV). Foi predominante a forma pulmonar da tuberculose (84,5%); constatou-se baciloscopia positiva em 50,5% dos casos e radiografia suspeita em 82,7%. Metade dos casos concentravam-se em sete bairros. Os resultados apontam a necessidade de desenvolver mais ações de saúde para controle da tuberculose entre homens adultos, idosos e nos bairros com mais infectados, além da importância de reavaliar os métodos diagnósticos utilizados em Barreiras.

This article sought to describe the epidemiological profile of tuberculosis in Barreiras, Bahia, Brazil, between 2008 and 2018. An epidemiological, descriptive, historical series study was conducted with data obtained from the Information System for Notifiable Diseases (SINAN), the Mortality Information System (SIM), and the Leonídia Ayres de Almeida Health Center. Incidence and mortality coefficients were calculated. Spatial distribution of cases by neighborhood was developed using ArcGIS v.10.2 software. In the 537 cases analyzed, men (57%) aged 35 to 49 years (26.8%) predominated, older adults (> 60 years) presented incidence and mortality higher than the national average, and 3.7% of patients were co-infected with HIV virus. Pulmonary tuberculosis was predominant (84.5%). Positive smear microscopy was found in 50.5% of cases and suspected radiography in 82.7%. Half of the cases were concentrated in seven neighborhoods. Results show the need for more health actions to control tuberculosis among adult men, older adults and in the most infected neighborhoods, besides the importance of reassessing the diagnostic methods used in Barreiras.

Este estudio tuvo por objetivo describir el perfil epidemiológico de la tuberculosis en Barreiras, en Bahía (Brasil), entre 2008-2018. Se trata de un estudio epidemiológico, descriptivo, de serie histórica, cuyos datos se obtuvieron del Sistema de Información de Agravamientos de Notificación (Sinan), del Sistema de Información de Mortalidad (SIM) y del Centro de Salud Leonídia Ayres de Almeida. Se calcularon los coeficientes de incidencia y mortalidad. La distribución espacial de casos por vecindario se desarrolló utilizando el software ArcGIS v.10.2. En los 537 casos analizados predominaron los hombres (57%), de entre 35-49 años (26,8%); los ancianos (> 60 años) tuvieron una incidencia y mortalidad superior a la media nacional; y el 3,7% de los pacientes fueron coinfectados por el virus de inmunodeficiencia humana (VIH). La forma pulmonar (84,5%) fue la más prevalente; se constató baciloscopia positiva en el 50,5% de los casos y sospecha de radiografía en el 82,7%. La mitad de los casos se concentraron en siete barrios. Los resultados indican que son necesarias más acciones de salud para controlar la tuberculosis en hombres adultos, ancianos y en los barrios con más contagios, además de una reevaluación de los métodos diagnósticos utilizados en Barreiras.

Coagulopathy and the humoral response against viral proteins in patients at different stages of COVID-19

BACKGROUND Patients with severe coronavirus disease 2019 (COVID-19) often present with coagulopathies and have high titres of circulating antibodies against viral proteins. OBJECTIVES Herein, we evaluated the association between D-dimer and circulating immunoglobulin levels against viral proteins in patients at different clinical stages of COVID-19. METHODS For this, we performed a cross-sectional study involving patients of the first wave of COVID-19 clinically classified as oligosymptomatic (n = 22), severe (n = 30), cured (n = 27) and non-infected (n = 9). Next, we measured in the plasma samples the total and fraction of immunoglobulins against the nucleoprotein (NP) and the receptor-binding domain (RBD) of the spike proteins by enzyme-linked immunosorbent assay (ELISA) assays. FINDINGS Patients with severe disease had a coagulation disorder with high levels of D-dimer as well as circulating IgG against the NP but not the RBD compared to other groups of patients. In addition, high levels of D-dimer and IgG against the NP and RBD were associated with disease severity among the patients in this study. MAIN CONCLUSIONS Our data suggest that IgG against NP and RBD participates in the worsening of COVID-19. Although the humoral response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is partially understood, and more efforts are needed to clarify gaps in the knowledge of this process.

Lipid droplets of protozoan parasites: survival and pathogenicity

Lipid droplets (LDs; lipid bodies) are intracellular sites of lipid storage and metabolism present in all cell types. Eukaryotic LDs are involved in eicosanoid production during several inflammatory conditions, including infection by protozoan parasites. In parasites, LDs play a role in the acquisition of cholesterol and other neutral lipids from the host. The number of LDs increases during parasite differentiation, and the biogenesis of these organelles use specific signaling pathways involving protein kinases. In addition, LDs are important in cellular protection against lipotoxicity. Recently, these organelles have been implicated in eicosanoid and specialised lipid metabolism. In this article, we revise the main functions of protozoan parasite LDs and discuss future directions in the comprehension of these organelles in the context of pathogen virulence.