Patients' perception regarding the influence of individual and social vulnerabilities on the adherence to tuberculosis treatment: a qualitative study

Background: Tuberculosis remains an important disease which mainly affects the majority of vulnerable individuals in society, who are subjected to poor living conditions and difficulties to access the services of public health. Under these circumstances, the present study aims to understand patients' perception in relation to the influence of individual and social vulnerabilities on the adherence to tuberculosis treatment. Methods: A qualitative descriptive cross sectional study was conducted in one large municipality at the state of Paraiba, Northeast of Brazil. The study subjects, who were residents of the study site, covered all tuberculosis cases diagnosed between March and June 2015. The sample was defined by the criteria of response saturation. All interviews were audio recorded, and data analysis was developed through the hermeneutic dialectic method and the theory of Generative Route Sense. The project was approved by the Research Ethics Committee of the University of Sao Paulo (USP). Results: A total of 13 individuals were interviewed and the responses were identified into two analytical categories: the difficulties they had and the enabling factors they could mention during their tuberculosis treatment. Patients brought up social exclusion as an obstacle to treatment adherence, which, along with stigmatization, weakened their link with family members and health professionals. Moreover, economic precariousness was a major hindrance to the maintenance of a proper diet and transportation access to health centers. However, social support and directly observed treatment helped to break down barriers of prejudice and to promote individual and family empowerment. Finally, patients also reported that their will to live and faith gave them the strength to continue with the treatment. Conclusions: According to patients in this study, social support and the strengthening of links with family members and health professionals may reduce social exclusion and other difficulties they face, thus encouraging them to the adhere to tuberculosis treatment.Univ Estadual Paraiba, Campina Grande, Paraiba, BrazilUniv Fed Rio Grande do Norte, Natal, RN, BrazilUniv Sao Paulo, Escola Enfermagem, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Escola Paulista Enfermagem, Sao Paulo, BrazilFac Santa Maria, Cajazeiras, Paraiba, BrazilUniv Fed Sao Paulo, Escola Paulista Enfermagem, Sao Paulo, BrazilWeb of Scienc

Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli

Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.  Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins.  Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets

Echinococcus granulosus Antigen B Structure: Subunit Composition and Oligomeric States

Antigen B (AgB) is the major secretory protein of the Echinococcus granulosus hydatid cyst, the causative agent of cystic hydatid disease. Structurally, AgB is a multisubunit protein formed by 8-kDa subunits, but it is not known which subunits are secreted by a single parasite (cyst) and how they interact in the formation of distinct AgB oligomeric states. Here, we investigated AgB subunit composition and oligomeric states in individual samples from bovine and human cysts. We identified AgB8/1, AgB8/2, AgB8/3 and AgB8/4 subunits in AgB oligomers of all samples analyzed. Quantitative and qualitative differences in the expression of AgB subunits were observed within and between samples. Using recombinant subunits as models, we showed that AgB subunits form distinct oligomeric states, with a rAgB8/3>rAgB8/2>rAgB8/1 maximum size relation. We also demonstrated by different experimental approaches that rAgB8/3 oligomers are more similar, both in size and morphology, to those observed for E. granulosus AgB. Overall, we provided experimental evidences that AgB is composed of different subunits within a single cyst, and that subunits have different abundances and oligomerization properties. These issues are important for the understanding of AgB expression and structure variations, and their impact for the host-parasite cross-talk

Chagasic Thymic Atrophy Does Not Affect Negative Selection but Results in the Export of Activated CD4+CD8+ T Cells in Severe Forms of Human Disease

Extrathymic CD4+CD8+ double-positive (DP) T cells are increased in some pathophysiological conditions, including infectious diseases. In the murine model of Chagas disease, it has been shown that the protozoan parasite Trypanosoma cruzi is able to target the thymus and induce alterations of the thymic microenvironment and the lymphoid compartment. In the acute phase, this results in a severe atrophy of the organ and early release of DP cells into the periphery. To date, the effect of the changes promoted by the parasite infection on thymic central tolerance has remained elusive. Herein we show that the intrathymic key elements that are necessary to promote the negative selection of thymocytes undergoing maturation during the thymopoiesis remains functional during the acute chagasic thymic atrophy. Intrathymic expression of the autoimmune regulator factor (Aire) and tissue-restricted antigen (TRA) genes is normal. In addition, the expression of the proapoptotic Bim protein in thymocytes was not changed, revealing that the parasite infection-induced thymus atrophy has no effect on these marker genes necessary to promote clonal deletion of T cells. In a chicken egg ovalbumin (OVA)-specific T-cell receptor (TCR) transgenic system, the administration of OVA peptide into infected mice with thymic atrophy promoted OVA-specific thymocyte apoptosis, further indicating normal negative selection process during the infection. Yet, although the intrathymic checkpoints necessary for thymic negative selection are present in the acute phase of Chagas disease, we found that the DP cells released into the periphery acquire an activated phenotype similar to what is described for activated effector or memory single-positive T cells. Most interestingly, we also demonstrate that increased percentages of peripheral blood subset of DP cells exhibiting an activated HLA-DR+ phenotype are associated with severe cardiac forms of human chronic Chagas disease. These cells may contribute to the immunopathological events seen in the Chagas disease

The role of P2 receptors in controlling infections by intracellular pathogens

A growing number of studies have demonstrated the importance of ATPe-signalling via P2 receptors as an important component of the inflammatory response to infection. More recent studies have shown that ATPe can also have a direct effect on infection by intracellular pathogens, by modulating membrane trafficking in cells that contain vacuoles that harbour intracellular pathogens, such as mycobacteria and chlamydiae. A conserved mechanism appears to be involved in controlling infection by both of these pathogens, as a role for phospholipase D in inducing fusion between lysosomes and the vacuoles has been demonstrated. Other P2-dependent mechanisms are most likely operative in the cases of pathogens, such as Leishmania, which survive in an acidic phagolysosomal-like compartment. ATPe may function as a ‘danger signal–that alerts the immune system to the presence of intracellular pathogens that damage the host cell, while different intracellular pathogens have evolved enzymes or other mechanisms to inhibit ATPe-mediated signalling, which should, thus, be viewed as virulence factors for these pathogens

HEALTH BELIEFS REGARDING DIET: A PERSPECTIVE OF HYPERTENSIVE BLACK INDIVIDUALS

The objective of this descriptive-exploratory study was to identify the health beliefs of black individuals with hypertension regarding the barriers and benefits of diet for controlling the disease, including the sociodemographic factors associated with the health beliefs surrounding diet control. One hundred and six black adults with hypertension were interviewed using a specific instrument. The data were analyzed considering the percentages, frequency of the cases, scores and prevalence ratio. The global analysis of beliefs showed a preponderance of beliefs regarding the benefits of diet control. It was observed that men, younger individuals, lack of a partner and low educational level and income were related to the beliefs regarding the benefits of adopting a healthy diet. In conclusion, health promotion among the black population requires an interdisciplinary approach and specific health policies addressing this populations' needs, aimed at preventive and curative aspects

Dental calculus evidence of Taï Forest Chimpanzee plant consumption and life history transitions

Dental calculus (calcified dental plaque) is a source of multiple types of data on life history. Recent research has targeted the plant microremains preserved in this mineralised deposit as a source of dietary and health information for recent and past populations. However, it is unclear to what extent we can interpret behaviour from microremains. Few studies to date have directly compared the microremain record from dental calculus to dietary records, and none with long-term observation dietary records, thus limiting how we can interpret diet, food acquisition and behaviour. Here we present a high-resolution analysis of calculus microremains from wild chimpanzees (Pan troglodytes verus) of Taï National Park, Côte d"Ivoire. We test microremain assemblages against more tan two decades of field behavioural observations to establish the ability of calculus to capture the composition of diet. Our results show that some microremain classes accumulate as long-lived dietary markers. Phytolith abundance in calculus can reflect the proportions of plants in the diet, yet this pattern is not true for starches. We also report microremains can record information about other dietary behaviours, such as the age of weaning and learned food processing techniques like nutcracking