Reduced Plasma Angiotensin Ii Levels Are Reversed By Hydroxyurea Treatment In Mice With Sickle Cell Disease.

Sickle cell disease (SCD) pathogenesis leads to recurrent vaso-occlusive and hemolytic processes, causing numerous clinical complications including renal damage. As vasoconstrictive mechanisms may be enhanced in SCD, due to endothelial dysfunction and vasoactive protein production, we aimed to determine whether the expression of proteins of the renin-angiotensin system (RAS) may be altered in an animal model of SCD. Plasma angiotensin II (Ang II) was measured in C57BL/6 (WT) mice and mice with SCD by ELISA, while quantitative PCR was used to compare the expressions of the genes encoding the angiotensin-II-receptors 1 and 2 (AT1R and AT2R) and the angiotensin-converting enzymes (ACE1 and ACE2) in the kidneys, hearts, livers and brains of mice. The effects of hydroxyurea (HU; 50-75mg/kg/day, 4weeks) treatment on these parameters were also determined. Plasma Ang II was significantly diminished in SCD mice, compared with WT mice, in association with decreased AT1R and ACE1 expressions in SCD mice kidneys. Treatment of SCD mice with HU reduced leukocyte and platelet counts and increased plasma Ang II to levels similar to those of WT mice. HU also increased AT1R and ACE2 gene expression in the kidney and heart. Results indicate an imbalanced RAS in an SCD mouse model; HU therapy may be able to restore some RAS parameters in these mice. Further investigations regarding Ang II production and the RAS in human SCD may be warranted, as such changes may reflect or contribute to renal damage and alterations in blood pressure.

Effect Of Particles Of Ashes Produced From Sugarcane Burning On The Respiratory System Of Rats.

The practice of burning sugarcane obtained by non-mechanized harvesting exposes workers and the people of neighboring towns to high concentrations of particulate matter (PM) that is harmful to health, and may trigger a series of cardiorespiratory diseases. The aim of this study was to analyze the chemical composition of the micro-particles coming from sugarcane burning residues and to verify the effects of this micro-particulate matter on lung and tracheal tissues. Micro-particulate matter (PM10) was obtained by dissolving filter paper containing burnt residues in NaCl solution. This material was instilled into the Wistar rats' nostrils. Histological analyses (hematoxylin and eosin - HE) of cardiac, lung and tracheal tissues were performed. Inflammatory mediators were measured in lung tissues by using ELISA. The chemical composition of the particulate material revealed a large quantity of the phthalic acid ester, high concentrations of phenolic compounds, anthracene and polycyclic aromatic hydrocarbons (PAH). Histological analysis showed a reduction in subjacent conjunctive tissue in the trachea, lung inflammation with inflammatory infiltrate formation and reduction of alveolar spaces and a significant increase (p<0.05) in the release of IL-1α, IL-1β, IL-6, and INF-γ in the group treated with PM10 when compared to the control group. We concluded that the burning sugarcane residues release many particles, which have toxic chemical compounds. The micro-particulate matter can induce alterations in the respiratory system.

Proinflammatory Activity Of Primarily Infected Endodontic Content Against Macrophages After Different Phases Of The Root Canal Therapy.

This study investigated the presence of target bacterial species and the levels of endotoxins in teeth with apical periodontitis. Levels of inflammatory mediators (interleukin [IL]-1β and tumor necrosis factor [TNF]-α) were determined after macrophage stimulation with endodontic content after different phases of endodontic therapy using different irrigants. Thirty primarily infected root canals were randomly assigned into 3 groups according to the irrigant used for root canal preparation (n = 10 per group): GI: 2.5% sodium hypochlorite, GII: 2% chlorhexidine gel, and GIII (control group): saline solution. Root canal samples were taken by using paper points before (s1) and after root canal instrumentation (s2), subsequently to 17% EDTA (s3), after 30 days of intracanal medication (Ca[OH]2 + saline solution) (s4), and before root canal obturation (s5). Polymerase chain reaction (16S recombinant DNA) and limulus amebocyte lysate assay were used for bacterial and endotoxin detection, respectively. Macrophages were stimulated with the root canal contents for IL-1β/TNF-α measurement using enzyme-linked immunosorbent assay. Porphyromonas gingivalis (17/30), Porphyromonas endodontalis (15/30), and Prevotella nigrescens (11/30) were the most prevalent bacterial species. At s1, endotoxins were detected in 100% of the root canals (median = 32.43 EU/mL). In parallel, substantial amounts of IL-1β and TNF-α were produced by endodontic content-stimulated macrophages. At s2, a significant reduction in endotoxin levels was observed in all groups, with GI presenting the greatest reduction (P < .05). After a root canal rinse with EDTA (s3), intracanal medication (s4), and before root canal obturation (s5), endotoxin levels reduced without differences between groups (P < .05). IL-1β and TNF-α release decreased proportionally to the levels of residual endotoxin (P < .05). Regardless of the use of sodium hypochlorite or CHX, the greatest endotoxin reduction occurs after chemomechanical preparation. Increasing steps of root canal therapy associated with intracanal medication enhances endotoxin reduction, leading to a progressively lower activation of proinflammatory cells such as macrophages.

Clinical Influence Of Different Intracanal Medications On Th1-type And Th2-type Cytokine Responses In Apical Periodontitis.

This clinical study assessed the influence of different intracanal medications on Th1-type and Th2-type cytokine responses in apical periodontitis and monitored the levels of bacteria from primarily infection during endodontic procedures. Thirty primarily infected teeth were randomly divided into 3 groups according to the medication selected: chlorhexidine (CHX), 2% CHX gel; Ca(OH)2/SSL, Ca(OH)2 + SSL; and Ca(OH)2/CHX, Ca(OH)2 + 2% CHX gel (all, n = 10). Bacterial sample was collected from root canals, and the interstitial fluid was sampled from lesions. Culture techniques were used to determine bacterial counts (colony-forming units/mL). Th1 (tumor necrosis factor-α, interferon-γ, and interleukin [IL]-2) and Th2 cytokines (IL-4, IL-5, and IL-13) were measured by enzyme-linked immunosorbent assay. All intracanal medication protocols were effective in reducing the bacterial load from root canals (all P < .05) and lowering the levels of Th1-type cytokines in apical lesions (all P < .05), with no differences between them (P > .05). Both Ca(OH)2 treatment protocols significantly increased the levels of Th2-type cytokines (P < .05), with no differences between them (P > .05). Thus, chlorhexidine medication showed the lowest effectiveness in increasing the levels of Th2-type cytokine. After treatment, regardless of the type of medication, the linear regression analysis indicated the down-regulation of Th2-type cytokines by Th1-type cytokines. All intracanal medication protocols were effective in reducing bacterial load and lowering the levels of Th1-type cytokines. Thus, the use of Ca(OH)2 medications contributed to the increase in the Th2-type cytokine response in apical periodontitis.

Evaluation of the effects of ozone therapy in the treatment of intra-abdominal infection in rats

INTRODUCTION: The antibacterial effect of ozone (O3) has been described in the extant literature, but the role of O3 therapy in the treatment of certain types of infection remains controversial. OBJECTIVES: To evaluate the effect of intraperitoneal (i.p.) O3 application in a cecal ligation/puncture rat model on interleukins (IL-6, IL-10) and cytokine-induced neutrophil chemoattractant (CINC)-1 serum levels, acute lung injury and survival rates. METHODS: Four animal groups were used for the study: a) the SHAM group underwent laparotomy; b) the cecal ligation/puncture group underwent cecal ligation/puncture procedures; and c) the CLP+O2 and CLP+O3 groups underwent CLP+ corresponding gas mixture infusions (i.p.) throughout the observation period. IL-6, CINC-1 and IL-10 concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Acute lung injury was evaluated with the Evans blue dye lung leakage method and by lung histology. P<0.05 was considered significant. RESULTS: CINC-1 was at the lowest level in the SHAM group and was lower for the CLP+O3 group vs. the CLP+O2 group and the cecal ligation/puncture group. IL-10 was lower for the SHAM group vs. the other three groups, which were similar compared to each other. IL-6 was lower for the SHAM group vs. all other groups, was lower for the CLP+O3 or CLP+O2 group vs. the cecal ligation/puncture group, and was similar for the CLP+O3 group vs. the CLP+O2 group. The lung histology score was lower for the SHAM group vs. the other groups. The Evans blue dye result was lower for the CLP+O3 group vs. the CLP+O2 group and the cecal ligation/puncture group but similar to that of the SHAM group. The survival rate for the CLP+O3 group was lower than for the SHAM group and similar to that for the other 2 groups (CLP and CLP+O2). CONCLUSION: Ozone therapy modulated the inflammatory response and acute lung injury in the cecal ligation/puncture infection model in rats, although there was no improvement on survival rates.

Anticorpos contra LDL-ox e síndrome coronariana aguda

FUNDAMENTO: A oxidação da lipoproteína de baixa densidade (LDL-ox) induz à formação de epítopos imunogênicos na molécula. A presença de autoanticorpos contra a LDL-ox tem sido demonstrada no soro de pacientes com doença arterial coronariana (DAC). Contudo, o papel desses autoanticorpos na fisiopatologia das síndromes coronarianas agudas (SCA) e o seu significado clínico permanecem indefinidos. OBJETIVO: Avaliar a associação entre autoanticorpos contra a LDL-ox e SCA. MÉTODOS: Os títulos de imunoglobulina G autoanticorpos contra a LDL-ox por cobre (antiLDL-ox) e contra o peptídeo sintético D derivado da apolipoproteína B (antipeptD) foram determinados por ensaio imunoenzimático (ELISA) em 90 pacientes, nas primeiras 12h de SCA (casos) e em 90 pacientes com DAC crônica (controles). RESULTADOS: Os resultados mostraram que os títulos de antiLDL-ox foram significativamente mais elevados (p = 0,017) nos casos (0,40 ± 0,22), do que nos controles (0,33 ± 0,23). Por outro lado, os títulos de antipeptD foram significativamente menores (p < 0,01) nos casos (0,28 ± 0,23) do que nos controles (0,45 ± 0,30). A diferença dos títulos de ambos anticorpos entre os dois grupos estudados foi independente de idade, sexo, hipertensão arterial, diabete melito, dislipidemia, índice de massa corporal, tabagismo, perfil lipídico, uso de estatinas e história familiar de DAC. CONCLUSÃO: Os resultados mostraram que os títulos de antiLDL-ox foram significativamente mais elevados nos pacientes com síndrome coronariana aguda quando comparados aos pacientes com doença arterial coronariana e podem estar associados à instabilidade da placa aterosclerótica.

Triagem sorológica e influência do conhecimento sobre a dengue em pacientes do ambulatório de especialidades do SUS

INTRODUÇÃO: A dengue é causa de preocupação em países como o Brasil. OBJETIVO: Verificar a soropositividade dos pacientes do ambulatório de especialidades do Sistema Único de Saúde (SUS) para anticorpos antidengue, relacionando os resultados com os dados sociodemográficos. METODOLOGIA: Foram respondidos 184 questionários de avaliação sociodemográfica e de conhecimento sobre a transmissão da dengue. Foi utilizado o método de imunoensaio enzimático (ELISA) para pesquisar imunoglobulina da classe M (IgM) e da classe G (IgG) contra os vírus. RESULTADOS: Quinze por cento dos pacientes apresentaram IgG contra o vírus, sem a presença de IgM. CONCLUSÃO: Os pacientes demonstraram conhecimento sobre a doença e sua prevenção, independentemente da classe econômica. A infecção assintomática deve ser avaliada, principalmente nos casos de doença febril.

Biotin-avidin sandwich elisa with specific human isotypes IgG1 and IgG4 for Culicidae mosquito blood meal identification from an epizootic yellow fever area in Brazil

With a view toward investigating the feeding behavior of Culicidae mosquitoes from an area of epizootic yellow fever transmission in the municipalities of Garruchos and Santo Antônio das Missões, Rio Grande do Sul State, Brazil, specimens were collected by aspiration from September 2005 to April 2007. The engorged females were submitted to blood meal identification by enzyme-linked immunosorbent assay (ELISA). A total of 142 blood-engorged samples were examined for human or monkey blood through species-specific IgG. Additional tests for specificity utilizing isotypes IgG1 and IgG4 of human monoclonal antibodies showed that only anti-human IgG1 was effective in recognizing blood meals of human origin. The results indicated a significant difference (p = 0.027) in detection patterns in samples of Haemagogus leucocelaenus recorded from human blood meals at Santo Antônio das Missões, which suggests some degree of exposure, since it was an area where epizootic outbreaks have been reported.

Características clínico-epidemiológicas da doença Lyme-símile em crianças

OBJETIVO: Determinar a prevalência, distribuição etária, sazonalidade, características clínicas da doença Lyme-símile em menores de 15 anos. MÉTODOS: De julho/1998 a dezembro/2000 foi conduzido um estudo transversal em 333 pacientes, com exantema e febre. Foram coletadas amostras pareadas de sangue para a identificação de patógenos. Somente em 193 amostras, negativas aos outros patógenos (Parvovirus B19, Herpesvírus 6 humano, Sarampo, Rubéola, Dengue, Escarlatina e Enterovírus), foram realizadas a pesquisa da borreliose pelos métodos de Enzyme-Linked Immunosorbent Assay e Western-blotting. Outras variáveis clínicas, socioeconômicas, demográficas e climáticas foram estudadas. RESULTADOS: A prevalência da doença foi de 6,2%(12/193). Das variáveis estudadas, houve predomínio em <6anos(83,2%); sexo feminino (66,7%); procedência da cidade de Franco da Rocha (58,3%); com sazonalidade no outono-verão. O intervalo de atendimento foi de quatro dias. Sinais e sintomas com significância estatística: prurido, ausência da fissura labial e bom estado clínico. Outros dados presentes foram: irritabilidade (80%); febre (?38ºC) (58,3%) com duração de um a três dias. O exantema foi do tipo máculo-papular (33,3%), urticariforme (25%) e escarlatiniforme (16,7%); predominando em tronco (60%). Não houve apresentação clínica característica para diagnóstico da doença de Lyme-símile nestes pacientes. A sensibilidade e especificidade para o diagnóstico clínico contraposta com o diagnóstico laboratorial foi zero. O acompanhamento de 10 casos durante dois anos não evidenciou complicações cardiológicas ou neurológicas. Este é o primeiro estudo desta doença em crianças brasileiras. CONCLUSÃO: A prevalência da doença Lyme-símile foi baixa, não tendo sido lembrada no diagnóstico inicial dos exantemas, mas seu conhecimento é necessário, necessitando maior atenção médica.

Epidemiological and ecological aspects related to malaria in the area of influence of the lake at Porto Primavera dam, in western São Paulo State, Brazil

A study was carried out in the area of influence of the Porto Primavera Hydroelectric Power Station, in western São Paulo State, to investigate ecological and epidemiological aspects of malaria in the area and monitor the profile of the anopheline populations following the environmental changes brought about by the construction of the lake. Mosquitoes captured were analyzed by standardized indicator species analysis (ISA) before and during different flooding phases (253 m and 257 m elevations). The local human population was studied by means of parasitological (thin/thick blood smears), molecular (PCR) and serological tests. Serological tests consisted of Enzyme Linked Immunosorbent Assay (ELISA) with synthetic peptides of the circumsporozoite protein (CSP) from classic Plasmodium vivax, P. vivax variants (VK247 and "vivax-like"), P. malariae and P. falciparum and Indirect Immunofluorescence Assay (IFA) with asexual forms of P. vivax, P. malariae and P. falciparum. The results of the entomological survey indicated that, although the Anopheles darlingi population increased after the flooding, the population density remained very low. No malaria, parasite infection or DNA was detected in the inhabitants of the study area. However, there was a low frequency of antibodies against asexual forms and a significant prevalence of antibodies against P. vivax, P. vivax variants, P. falciparum and P. malariae; the presence of these antibodies may result from recent or less recent contact with human or simian Plasmodium (a parallel study in the same area revealed the existence of a sylvatic cycle). Nevertheless, these results suggest that, as in other places where malaria is present and potential vectors circulate, the local epidemiological conditions observed could potentially support the transmission of malaria in Porto Primavera Lake if infected individuals are introduced in sufficient numbers. Further studies are required to elucidate the phenomena described in this paper.

Circulation of antibodies against yellow fever virus in a simian population in the area of Porto Primavera Hydroelectric Plant, São Paulo, Brazil

Yellow fever (YF) is an acute viral infectious disease transmitted by mosquitoes which occurs in two distinct epidemiological cycles: sylvatic and urban. In the sylvatic cycle, the virus is maintained by monkey's infection and transovarian transmission in vectors. Surveillance of non-human primates is required for the detection of viral circulation during epizootics, and for the identification of unaffected or transition areas. An ELISA (enzyme-linked immunosorbent assay) was standardized for estimation of the prevalence of IgG antibodies against yellow fever virus in monkey sera (Alouatta caraya) from the reservoir area of Porto Primavera Hydroelectric Plant, in the state of São Paulo, Brazil. A total of 570 monkey sera samples were tested and none was reactive to antibodies against yellow fever virus. The results corroborate the epidemiology of yellow fever in the area. Even though it is considered a transition area, there were no reports to date of epizootics or yellow fever outbreaks in humans. Also, entomological investigations did not detect the presence of vectors of this arbovirus infection. ELISA proved to be fast, sensitive, an adequate assay, and an instrument for active search in the epidemiological surveillance of yellow fever allowing the implementation of prevention actions, even before the occurrence of epizootics.

Ecologia de Haemagogus e Sabethes (Diptera: Culicidae) em áreas epizoóticas do vírus da febre amarela, Rio Grande do Sul, Brasil

Objetivou-se com este estudo investigar característica ecológica e o hábito alimentar de Haemagogus e Sabethes em área epizoótica da febre amarela silvestre em duas localidades do Rio Grande do Sul, capturados com aspirador, armadilha de Shannon e puçá. Para identificação do sangue ingerido pelas fêmeas foi utilizada a técnica imunoenzimática ELISA de captura. Obteve-se maior atividade de Hg. leucocelaenus na primavera e outono, entre 12 e 17 horas, enquanto Sabethes albiprivus e Sa. quasycianus durante todo o ano. Para fêmeas de Hg. leucocelaenus em Santo Antônio das Missões, houve predomínio de sangue humano e para as demais espécies destaca-se a atratividade para bovinos nos dois municípios. A capacidade vetorial do Hg. leucocelaenus fundamenta vigilância entomológica em seu papel de estratificar áreas problemas ou a sustentabilidade do programa de imunização da população

Population-based multicentric survey of hepatitis B infection and risk factor differences among three regions in Brazil

This multicentric population-based study in Brazil is the first national effort to estimate the prevalence of hepatitis B (HBV) and risk factors in the capital cities of the Northeast, Central-West, and Federal Districts (2004-2005). Random multistage cluster sampling was used to select persons 13-69 years of age. Markers for HBV were tested by enzyme-linked immunosorbent assay. The HBV genotypes were determined by sequencing hepatitis B surface antigen (HBsAg). Multivariate analyses and simple catalytic model were performed. Overall, 7,881 persons were included; < 70 per cent were not vaccinated. Positivity for HBsAg was less than 1 per cent among non-vaccinated persons and genotypes A, D, and F co-circulated. The incidence of infection increased with age with similar force of infection in all regions. Males and persons having initiated sexual activity were associated with HBV infection in the two settings; healthcare jobs and prior hospitalization were risk factors in the Federal District. Our survey classified these regions as areas with HBV endemicity and highlighted the risk factors differences among the settings

Circulation of antibodies against yellow fever virus in a simian population in the area of Porto Primavera hydroeletric plant, São Paulo, Brazil

A febre amarela (FA) é doença infecciosa aguda de origem viral transmitida por mosquitos. No ciclo silvestre, o vírus é mantido por meio da infecção de macacos e da transmissão transovariana nos vetores. A vigilância sobre populações de primatas não humanos torna-se necessária para detectar a circulação viral, quando ainda está restrito a epizootias, e para determinar sua presença em regiões indenes ou de transição para a doença. Padronizou-se a técnica ELISA (Enzyme Linked Immunosorbent Assay) para determinar a prevalência de anticorpos da classe IgG contra o vírus da FA em soros de bugios (Alouatta caraya) da região do reservatório da Usina Hidrelétrica de Porto Primavera, SP. Foram testados soros de 570 macacos sendo que nenhuma amostra mostrou-se reativa para a presença de anticorpos contra o vírus da FA. Os resultados são coerentes com a epidemiologia da FA na região. Mesmo sendo área de transição, não se conhece, até o momento, ocorrência de epizootia ou surto de FA em humanos e investigações entomológicas não apontaram a presença de vetores para esta arbovirose. A técnica mostrou-se sensível, rápida e útil à vigilância epidemiológica como instrumento de busca ativa permitindo desencadear ações preventivas, como vacinação, antes mesmo do surgimento de epizootias

Detection of Hepatitis B virus subgenotype A1 in a Quilombo community from Maranhao, Brazil

Background: The Brazilian population is mainly descendant from European colonizers, Africans and Native Americans. Some Afro-descendants lived in small isolated communities since the slavery period. The epidemiological status of HBV infection in Quilombos communities from northeast of Brazil remains unknown. The aim of this study was to characterize the HBV genotypes circulating inside a Quilombo isolated community from Maranhao State, Brazil. Methods: Seventy-two samples from Frechal Quilombo community at Maranhao were collected. All serum samples were screened by enzyme-linked immunosorbent assays for the presence of hepatitis B surface antigen ( HBsAg). HBsAg positive samples were submitted to DNA extraction and a fragment of 1306 bp partially comprising HBsAg and polymerase coding regions (S/POL) was amplified by nested PCR and its nucleotide sequence was determined. Viral isolates were genotyped by phylogenetic analysis using reference sequences from each genotype obtained from GenBank (n = 320). Sequences were aligned using Muscle software and edited in the SE-AL software. Bayesian phylogenetic analyses were conducted using Markov Chain Monte Carlo (MCMC) method to obtain the MCC tree using BEAST v.1.5.3. Results: Of the 72 individuals, 9 (12.5%) were HBsAg-positive and 4 of them were successfully sequenced for the 1306 bp fragment. All these samples were genotype A1 and grouped together with other sequences reported from Brazil. Conclusions: The present study represents the first report on the HBV genotypes characterization of this community in the Maranhao state in Brazil where a high HBsAg frequency was found. In this study, we reported a high frequency of HBV infection and the exclusive presence of subgenotype A1 in an Afro-descendent community in the Maranhao State, Brazil.