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Vaccine development against Plasmodium vivax malaria lags behind that for Plasmodium falciparum . To narrow this gap, we administered recombinant antigens based on P. vivax circumsporozoite protein (CSP) to mice. We expressed in Pichia pastoris two chimeric proteins by merging the three central repeat regions of different CSP alleles (VK210, VK247, and P. vivax -like). The first construct (yPvCSP-All FL ) contained the fused repeat regions flanked by N- and C-terminal regions. The second construct (yPvCSP-All CT ) contained the fused repeat regions and the C-terminal domain, plus RI region. Mice were vaccinated with three doses of yPvCSP in adjuvants Poly (I:C) or Montanide ISA720. We also used replication-defective adenovirus vectors expressing CSP of human serotype 5 (AdHu5) and chimpanzee serotype 68 (AdC68) for priming mice which were subsequently boosted twice with yPvCSP proteins in Poly (I:C) adjuvant. Regardless of the regime used, immunized mice generated high IgG titres specific to all CSP alleles. After challenge with P. berghei ANKA transgenic parasites expressing Pb/PvVK210 or Pb/PvVK247 sporozoites, significant time delays for parasitemia were observed in all vaccinated mice. These vaccine formulations should be clinically tried for their potential as protective universal vaccine against P. vivax malaria.

AbstractThe World Health Organization indicates that more than 1.5 billion people are infected with geohelminths. Soil-transmitted helminths prevail mostly in tropical and subtropical regions, in areas with inadequate hygiene and sanitation conditions, and basic health education problems. Nematode eggs are structures of resistance and infection by fecal-oral transmission. When STH eggs are ingested, they can infect the potential host, causing abdominal pain, diarrhea, anemia, malnutrition, and physical-cognitive impacts in children. Taking advantage of the increasing employment of three-dimensional models of these structured based on light microscopy images to improve the research area and education could be an alternative to improve health education and spread scientific information on transmission and prevention. The objective of this work was to produce 3D printed models from bi-dimensional images of eggs based on their real morphological and morphometric characteristics. The virtual models were reconstructed from the acquisition and selection of images obtained using light microscopy. After selecting referential images, we constructed the models based on the vectorization of the egg structures. After vectorization, 3D modeling was performed and printed in PLA. 3D models have a high potential to contribute to the advanced morphological studies and teaching of parasitological sciences, enriching the teaching-learning process applicable in presential or remote teaching of basic education, undergraduate, and post-graduation classes.

Enteropathogenic Escherichia coli (EPEC) produce a capsule of polysaccharides identical to those composing the O-antigen polysaccharide of its LPS (lipopolysaccharide) molecules. In light of this, the impact of O26 polysaccharides on the immune evasion mechanisms of capsulated O26 EPEC compared to non-capsulated enterohemorrhagic Escherichia coli (EHEC) was investigated. Our findings reveal that there was no significant difference between the levels in EPEC and EHEC of rhamnose (2.8:2.5), a molecule considered to be a PAMP (Pathogen Associated Molecular Patterns). However, the levels of glucose (10:1.69), heptose (3.6:0.89) and N-acetylglucosamine (4.5:2.10), were significantly higher in EPEC than EHEC, respectively. It was also observed that the presence of a capsule in EPEC inhibited the deposition of C3b on the bacterial surface and protected the pathogen against lysis by the complement system. In addition, the presence of a capsule also protected EPEC against phagocytosis by macrophages. However, the immune evasion provided by the capsule was overcome in the presence of anti-O26 polysaccharide antibodies, and additionally, these antibodies were able to inhibit O26 EPEC adhesion to human epithelial cells. Finally, the results indicate that O26 polysaccharides can generate an effective humoral immune response, making them promising antigens for the development of a vaccine against capsulated O26 E. coli.

Cryptococcosis is an opportunistic disease caused by the fungus Cryptococcus neoformans and Cryptococcus gattii . It starts as a pulmonary infection that can spread to other organs, such as the brain, leading to the most serious occurrence of the disease, meningoencephalitis. The humoral response has already been described in limiting the progression of cryptococcosis where the B-1 cell seems to be responsible for producing natural IgM antibodies, crucial for combating fungal infections. The role of the B-1 cell in C. neoformans infection has been initially described, however the role of the humoral response of B-1 cells has not yet been evaluated during C. gattii infections. In the present study we tried to unravel this issue using XID mice, a murine model deficient in the Btk protein which compromises the development of B-1 lymphocytes. We use the XID mice compared to BALB/c mice that are sufficient for the B-1 population during C. gattii infection. Our model of chronic lung infection revealed that XID mice, unlike the sufficient group of B-1, had early mortality with significant weight loss, in addition to reduced levels of IgM and IgG specific to GXM isolated from the capsule of C. neoformans . In addition to this, we observed an increased fungal load in the blood and in the brain. We described an increase in the capsular size of C. gattii and the predominant presence of cytokines with a Th2 profile was also observed in these animals. Thus, the present study strongly points to a higher susceptibility of the XID mouse to C. gattii , which suggests that the presence of B-1 cells and anti-GXM antibodies is fundamental during the control of infection by C. gattii .

Circumsporozoite protein (CSP) variants of P. vivax , besides having variations in the protein repetitive portion, can differ from each other in aspects such as geographical distribution, intensity of transmission, vectorial competence and immune response. Such aspects must be considered to P. vivax vaccine development. Therefore, we evaluated the immunogenicity of novel recombinant proteins corresponding to each of the three P. vivax allelic variants (VK210, VK247 and P. vivax -like) and of the C-terminal region (shared by all PvCSP variants) in naturally malaria-exposed populations of Brazilian Amazon. Our results demonstrated that PvCSP-VK210 was the major target of humoral immune response in studied population, presenting higher frequency and magnitude of IgG response. The IgG subclass profile showed a prevalence of cytophilic antibodies (IgG1 and IgG3), that seem to have an essential role in protective immune response. Differently of PvCSP allelic variants, antibodies elicited against C-terminal region of protein did not correlate with epidemiological parameters, bringing additional evidence that humoral response against this protein region is not essential to protective immunity. Taken together, these findings increase the knowledge on serological response to distinct PvCSP allelic variants and may contribute to the development of a global and effective P. vivax vaccine.

This study aims to investigate the prevalence of alcohol and tobacco experimentation among adolescents of the Brazilian Midwest its association with sociodemographic factors. This is a cross-sectional study, with data from the National School Health Survey - PeNSE, carried out in 2015. The sample consisted of ninth-graders. The dependent variable was alcohol and tobacco experimentation at some point in life. A Poisson regression model was performed to identify the associated variables. The weighted estimated prevalence of alcohol and tobacco experimentation was 57.17% (95% CI: 56.20-58.14) and 22.38% (95% CI: 21.56-23.20), respectively. The prevalence of alcohol experimentation among females was higher than in males. However, regarding tobacco, males had a higher prevalence than females. Alcohol and tobacco experimentation was statistically significant with age. Public schools' administrative dependency showed a 23.99% higher prevalence than private schools concerning tobacco experimentation. We concluded that alcohol and tobacco experimentation was high among school adolescents and was shown to be associated with sociodemographic factors .

The long term and complex nature of Chagas disease in humans has restricted studies on vaccine feasibility. Animal models also have limitations due to technical difficulties in monitoring the extremely low parasite burden that is characteristic of chronic stage infections. Advances in imaging technology offer alternative approaches that circumvent these problems. Here, we describe the use of highly sensitive whole body in vivo imaging to assess the efficacy of recombinant viral vector vaccines and benznidazole-cured infections to protect mice from challenge with Trypanosoma cruzi. Mice were infected with T. cruzi strains modified to express a red-shifted luciferase reporter. Using bioluminescence imaging, we assessed the degree of immunity to re-infection conferred after benznidazole-cure. Those infected for 14 days or more, prior to the onset of benznidazole treatment, were highly protected from challenge with both homologous and heterologous strains. There was a >99% reduction in parasite burden, with parasites frequently undetectable after homologous challenge. This level of protection was considerably greater than that achieved with recombinant vaccines. It was also independent of the route of infection or size of the challenge inoculum, and was long-lasting, with no significant diminution in immunity after almost a year. When the primary infection was benznidazole-treated after 4 days (before completion of the first cycle of intracellular infection), the degree of protection was much reduced, an outcome associated with a minimal T. cruzi-specific IFN-γ+ T cell response. Our findings suggest that a protective Chagas disease vaccine must have the ability to eliminate parasites before they reach organs/tissues, such as the GI tract, where once established, they become largely refractory to the induced immune response.

Enteropathogenic Escherichia coli (EPEC) produce a capsule of polysaccharides identical to those composing the O-antigen polysaccharide of its LPS (lipopolysaccharide) molecules. In light of this, the impact of O26 polysaccharides on the immune evasion mechanisms of capsulated O26 EPEC compared to non-capsulated enterohemorrhagic Escherichia coli (EHEC) was investigated. Our findings reveal that there was no significant difference between the levels in EPEC and EHEC of rhamnose (2.8:2.5), a molecule considered to be a PAMP (Pathogen Associated Molecular Patterns). However, the levels of glucose (10:1.69), heptose (3.6:0.89) and N-acetylglucosamine (4.5:2.10), were significantly higher in EPEC than EHEC, respectively. It was also observed that the presence of a capsule in EPEC inhibited the deposition of C3b on the bacterial surface and protected the pathogen against lysis by the complement system. In addition, the presence of a capsule also protected EPEC against phagocytosis by macrophages. However, the immune evasion provided by the capsule was overcome in the presence of anti-O26 polysaccharide antibodies, and additionally, these antibodies were able to inhibit O26 EPEC adhesion to human epithelial cells. Finally, the results indicate that O26 polysaccharides can generate an effective humoral immune response, making them promising antigens for the development of a vaccine against capsulated O26 E. coli.

Resumo O estudo tem como objetivo investigar a prevalência da experimentação do álcool e tabaco em adolescentes da região Centro-Oeste do Brasil e sua associação com fatores sociodemográficos. Estudo transversal, utilizando dados da Pesquisa Nacional de Saúde do Escolar – PeNSE, realizada em 2015. A amostra foi composta por escolares do 9° ano do Ensino Fundamental. A variável dependente foi a experimentação do álcool e tabaco alguma vez na vida. Para identificação das variáveis associadas, foi realizada a análise de regressão de Poisson . A prevalência estimada ponderada da experimentação do álcool e do tabaco foi de 57,17% (IC95%: 56,20 a 58,14) e 22,38% (IC95%: 21,56 a 23,20), respectivamente. A prevalência de experimentação do álcool no sexo feminino foi maior que nos meninos; no entanto, para o tabaco, o sexo masculino apresentou prevalência maior que o sexo feminino. A experimentação do álcool e tabaco foi estatisticamente significativa com o avançar da idade. A dependência administrativa das escolas públicas expôs prevalência de 23,99% maior que as privadas na experimentação do tabaco. Conclui-se que a experimentação do álcool e tabaco, entre os adolescentes escolares, apresentou-se elevada e associada aos fatores sociodemográficos. Abstract This study aims to investigate the prevalence of alcohol and tobacco experimentation among adolescents of the Brazilian Midwest its association with sociodemographic factors. This is a cross-sectional study, with data from the National School Health Survey – PeNSE, carried out in 2015. The sample consisted of ninth-graders. The dependent variable was alcohol and tobacco experimentation at some point in life. A Poisson regression model was performed to identify the associated variables. The weighted estimated prevalence of alcohol and tobacco experimentation was 57.17% (95% CI: 56.20-58.14) and 22.38% (95% CI: 21.56-23.20), respectively. The prevalence of alcohol experimentation among females was higher than in males. However, regarding tobacco, males had a higher prevalence than females. Alcohol and tobacco experimentation was statistically significant with age. Public schools’ administrative dependency showed a 23.99% higher prevalence than private schools concerning tobacco experimentation. We concluded that alcohol and tobacco experimentation was high among school adolescents and was shown to be associated with sociodemographic factors .

Abstract Objective To identify patterns of resistance against various antibiotics in Enterococcus faecalis in urinary tract infections in a population of the Toluca valley, Mexico Methods 155 samples were collected from patients with suspected urinary tract infection without exclusion criteria such as age or gender. Automated equipment was used for the identification of the etiological agent and sensitivity tests. Results 80 positive cultures were obtained, of which 20 strains belong to Enterococcus faecalis, which show 100% sensitivity for penicillins, linezolid, vancomycin, bacitracin, a high pattern of sensitivity for quinolones, and a high pattern of resistance to rifampicin, erythromycin and 100% resistance in tetracycline Conclusion It shows 100% sensitivity to penicillins, vancomycin and linezolid, first-line treatments and for cases of infection complicated by Enterococci. And 100% resistance for tetracycline and high resistance patterns for erythromycin and rifampin. Competing Interest Statement The authors have declared no competing interest.