Analysis of Chromobacterium sp. natural isolates from different Brazilian ecosystems

<p>Abstract</p> <p>Background</p> <p><it>Chromobacterium violaceum </it>is a free-living bacterium able to survive under diverse environmental conditions. In this study we evaluate the genetic and physiological diversity of <it>Chromobacterium </it>sp. isolates from three Brazilian ecosystems: Brazilian Savannah (Cerrado), Atlantic Rain Forest and Amazon Rain Forest. We have analyzed the diversity with molecular approaches (16S rRNA gene sequences and amplified ribosomal DNA restriction analysis) and phenotypic surveys of antibiotic resistance and biochemistry profiles.</p> <p>Results</p> <p>In general, the clusters based on physiological profiles included isolates from two or more geographical locations indicating that they are not restricted to a single ecosystem. The isolates from Brazilian Savannah presented greater physiologic diversity and their biochemical profile was the most variable of all groupings. The isolates recovered from Amazon and Atlantic Rain Forests presented the most similar biochemical characteristics to the <it>Chromobacterium violaceum </it>ATCC 12472 strain. Clusters based on biochemical profiles were congruent with clusters obtained by the 16S rRNA gene tree. According to the phylogenetic analyses, isolates from the Amazon Rain Forest and Savannah displayed a closer relationship to the <it>Chromobacterium violaceum </it>ATCC 12472. Furthermore, 16S rRNA gene tree revealed a good correlation between phylogenetic clustering and geographic origin.</p> <p>Conclusion</p> <p>The physiological analyses clearly demonstrate the high biochemical versatility found in the <it>C. violaceum </it>genome and molecular methods allowed to detect the intra and inter-population diversity of isolates from three Brazilian ecosystems.</p

Genotypic and phenotypic diversity of Bacillus spp. isolated from steel plant waste

Background: Molecular studies of Bacillus diversity in various environments have been reported. However, there have been few investigations concerning Bacillus in steel plant environments. In this study, genotypic and phenotypic diversity and phylogenetic relationships among 40 bacterial isolates recovered from steel plant waste were investigated using classical and molecular methods. Results: 16S rDNA partial sequencing assigned all the isolates to the Bacillus genus, with close genetic relatedness to the Bacillus subtilis and Bacillus cereus groups, and to the species Bacillus sphaericus. tDNA-intergenic spacer length polymorphisms and the 16S–23S intergenic transcribed spacer region failed to identify the isolates at the species level. Genomic diversity was investigatedby molecular typing with rep (repetitive sequence) based PCR using the primer sets ERIC2 (enterobacterial repetitive intergenic consensus), (GTG)5, and BOXAIR. Genotypic fingerprinting of the isolates reflected high intraspecies and interspecies diversity. Clustering of the isolates using ERIC-PCR fingerprinting was similar to that obtained from the 16S rRNA gene phylogenetic tree, indicating the potential of the former technique as a simple and useful tool for examining relationships among unknown Bacillus spp. Physiological, biochemical and heavy metal susceptibility profiles also indicated considerable phenotypic diversity. Among the heavy metal compounds tested Zn, Pb and Cu were least toxic to the bacterial isolates, whereas Ag inhibited all isolates at 0.001 mM. Conclusion: Isolates with identical 16S rRNA gene sequences had different genomic fingerprints and differed considerably in their physiological capabilities, so the high levels of phenotypic diversity found in this study are likely to have ecological relevance

Transcription of toll-like receptors 2, 3, 4 and 9, FoxP3 and Th17 cytokines in a susceptible experimental model of canine Leishmania infantum infection

Canine leishmaniosis (CanL) due to Leishmania infantum is a chronic zoonotic systemic disease resulting from complex interactions between protozoa and the canine immune system. Toll-like receptors (TLRs) are essential components of the innate immune system and facilitate the early detection of many infections. However, the role of TLRs in CanL remains unknown and information describing TLR transcription during infection is extremely scarce. The aim of this research project was to investigate the impact of L. infantum infection on canine TLR transcription using a susceptible model. The objectives of this study were to evaluate transcription of TLRs 2, 3, 4 and 9 by means of quantitative reverse transcription polymerase chain reaction (qRT-PCR) in skin, spleen, lymph node and liver in the presence or absence of experimental L. infantum infection in Beagle dogs. These findings were compared with clinical and serological data, parasite densities in infected tissues and transcription of IL-17, IL-22 and FoxP3 in different tissues in non-infected dogs (n = 10), and at six months (n = 24) and 15 months (n = 7) post infection. Results revealed significant down regulation of transcription with disease progression in lymph node samples for TLR3, TLR4, TLR9, IL-17, IL-22 and FoxP3. In spleen samples, significant down regulation of transcription was seen in TLR4 and IL-22 when both infected groups were compared with controls. In liver samples, down regulation of transcription was evident with disease progression for IL-22. In the skin, upregulation was seen only for TLR9 and FoxP3 in the early stages of infection. Subtle changes or down regulation in TLR transcription, Th17 cytokines and FoxP3 are indicative of the silent establishment of infection that Leishmania is renowned for. These observations provide new insights about TLR transcription, Th17 cytokines and Foxp3 in the liver, spleen, lymph node and skin in CanL and highlight possible markers of disease susceptibility in this model

The magnitude of syphilis: from prevalence to vertical transmission

ABSTRACT Introduction: In 2013, the World Health Organization (WHO) reported that 1.9 million pregnant women were infected with syphilis worldwide, of which 66.5% had adverse fetal effects in cases of untreated syphilis. Congenital syphilis contributes significantly to infant mortality, accounting for 305,000 perinatal deaths worldwide annually. Aim: To estimate the prevalence of syphilis in parturients, the incidence of congenital syphilis and the vertical transmission rate. Material and methods: a cross-sectional study with data collected from 2041 parturients who had undergone treatment between 2012 and 2014 in the maternity section of the Pedro Ernesto Hospital of the State University of Rio de Janeiro, in the metropolitan area of Rio de Janeiro. The inclusion criterion was positive VDRL and treponemal test in a hospital environment. Results: the prevalence of syphilis in pregnant women was 4.1% in 2012, 3.1% in 2013 and 5% in 2014, with official reporting of 15.6%, 25.0% and 48.1%, respectively. The incidence of congenital syphilis (CS) was 22/1,000 in live births (LB) in 2012; 17/1,000 LB in 2013 and 44.8/1,000 LB in 2014. CS underreporting during the period was 6.7%. Vertical transmission occurred in 65.8% of infants from infected mothers. It was concluded that, in 34.6% of the CS cases, maternal VDRL titers were = 1/4. Conclusion: Results demonstrate the magnitude of the disease, fragility of the reporting system in the assessment of the actual prevalence, impact on perinatal outcomes, and they are a warning about the real situation of syphilis, which is still underestimated in the State

Microalgae Schizochytrium sp. in diets for Piau juvenilles

Todos os textos, informa??es e resultados apresentados s?o de inteira responsabilidade dos autores.O DHA ? um ?cido importante da s?rie ?mega 3, fundamental para a forma??o do tecido nervoso e visual em humanos, e confere tamb?m uma boa forma??o da massa encef?lica. O presente trabalho teve o objetivo de avaliar dietas contendo a inclus?o da alga Schizochytrium sp. no desempenho produtivo de juvenis de piau.O experimento foi conduzido no Laborat?rio de Aquicultura e Ecologia Aqu?tica do Departamento de Zootecnia da Universidade Federal dos Vales do Jequitinhonha e Mucuri, em Diamantina MG. Foram utilizados 300 juvenis de Piau (Leporinus friderici) com peso e comprimento total m?dio de 11,8 e 9,68 g respectivamente . Os peixes passaram por sete dias de adapta??o e foram alimentados com a ra??o do tratamento controle. . O experimento foi realizado em um delineamento inteiramente casualizado, com cinco tratamentos (0, 10, 20, 30, e 40 g de Schizochytrium sp/kg-1)e quatro repeti??es. Sete juvenis foram estocados por aqu?rio, totalizando 20 parcelas experimentais. Avaliou-se aos 60 dias de experimento par?metros de desempenho produtivo. Foram mensurados: comprimento padr?o (cm), comprimento total (cm), ganho de peso (g), consumo de ra??o (g), convers?o alimentar (g/g)?, biomassa final (g), e sobreviv?ncia (%). As vari?veis de desempenho apresentaram melhores resultados de acordo com o aumento do n?vel de inclus?o da alga Schizochytrium sp em juvenis de piau. Conlcui-se com este estudo que juvenis de piau alimentados com 40g de Schizochytrium sp.kg-1 apresentam melhor desempenho produtivo e sobreviv?ncia.DHA is an important acid of the omega-3 series, essential for the formation of the nervous and visual tissue in humans, and also gives a good formation of brain matter. This study aimed to evaluate diets with the inclusion of algae Schizochytrium sp. In productive performance of piau juveniles.. Experiment was conducted at the Aquaculture Laboratory of Aquatic Ecology of the Department of Animal Science, of the Federal University of the Jequitinhonha and Mucuri Valleys, in Diamantina MG. . Three hundred Piau (Leporinus friderici) juvenile, with body weight and length means of 11.8, and 9.68 g respectively. Fish have undergone seven days of adaptation and were fed with the control ration treatment. The experiment was conducted in a completely randomized design, with five treatments (0, 10, 20, 30, and 40 g of Schizochytrium sp. Kg-1) and four replications. Seven juveniles were stocked per aquarium, totaling 20 experimental plots. It was evaluated at 60 days of the experiment For the productive performance were measured: standard length (cm), total length (cm), weight gain (g), feed intake (g), feed conversion (g / g) ? , final biomass (g) EC (%) and survival (%). The performance variables showed greater results in accordance with the increase in the level of inclusionof Schizochytrium sp in piau juveniles diets. It follows that piau juveniles fed with 40g Schizochytrium sp.kg-1 have greater growth performance and survival