Caracterização da microbiota vaginal, intestinal e oral durante o período gestacional / Vaginal, gut and oral microbiota characterization during pregnancy

A simbiose desenvolvida entre seres vivos e microrganismos desempenha um importante papel na relação saúde-doença do hospedeiro. Neste sentido, o corpo humano abriga uma grande e diversa comunidade de microrganismos, sendo as mucosas vaginal, intestinal e oral as principais superfícies mucosas do corpo feminino que abrigam as comunidades bacterianas de fundamental importância para a mulher. Estes microrganismos atuam no desenvolvimento e modulação do sistema imune, na manutenção e otimização de vias metabólicas e competem por sítios de colonização, prevenindo que microrganismos patogênicos estabeleçam colonização. A composição da microbiota feminina varia com a idade, pH, secreção hormonal, ciclo menstrual, uso de anticoncepcional e atividade sexual. O presente estudo buscou caracterizar a composição da microbiota do corpo feminino durante o período gestacional, comparando os achados entre gestantes e não gestantes saudáveis, através de técnicas de biologia molecular. Foram selecionadas 60 mulheres saudáveis para o estudo e coletadas amostras de secreção vaginal, fezes e swab oral de cada participante. O DNA das amostras foi extraído e submetido à sequenciamento do gene 16S rRNA e quantificado através da técnica de PCR em tempo real. Das participantes selecionadas, 42 eram gestantes e 18 eram mulheres não gestantes em idade reprodutiva. Observamos que a quantificação total de bactérias na vagina não apresentou diferenças entre gestantes e não gestantes. Houve aumento na abundância de Lactobacillus no sítio vaginal, bactérias produtoras de butirato na microbiota intestinal e Streptococcus na microbiota oral de mulheres grávidas quando comparadas com mulheres não gestantes. Além disso, observamos que a composição e a disposição dos gêneros encontrados sofrem uma modificação, tal como aumento de gêneros relacionados com a manutenção da homeostase no grupo de mulheres gestantes. O período gestacional influencia positivamente na composição da microbiota, garantindo assim a prevalência de gêneros bacterianos responsáveis pela manutenção das condições ideais para o desenvolvimento da gestação saudável

The symbiosis developed between living organisms and microorganisms plays an important role in the health-disease relationship of the host. In this sense, the human body harbor a large and diverse community of microorganisms, the vaginal, intestinal and oral mucosa are the main mucosal surfaces of the female body that harbor bacterial communities of fundamental importance for women. These microorganisms act in the development and modulation of the immune system, in the maintenance and optimization of metabolic pathways and compete for colonization sites, preventing pathogenic microorganisms from establishing colonization. The composition of the female microbiota varies with age, pH, hormonal secretion, menstrual cycle, contraceptive use and sexual activity. The present study aimed to characterize the microbiota composition of the female body during the gestational period, comparing the findings between healthy and non - pregnant women through molecular biology techniques. Sixty healthy women were selected for the study and samples of vaginal secretion, stool and oral swab from each participant were collected. The DNA of the samples was extracted and submitted to the 16S rRNA gene sequencing and quantified by the real-time PCR technique. Were select, 42 were pregnant and 18 were non-pregnant women of reproductive age. We observed that the total quantification of bacteria in the vaginal samples did not present differences between pregnant and non-pregnant women. There was an increase in the abundance of Lactobacillus in the vaginal site, butyrate producing bacteria in the intestinal microbiota and Streptococcus in the oral microbiota of pregnant women when compared to nonpregnant women. In addition, we observed that the composition and arrangement of the genera found undergo a modification, such as an increase in genera related to the maintenance of homeostasis in the group of pregnant women. The pregnancy influences the composition of the microbiota, thus ensuring the prevalence of bacterial genera responsible for the maintenance of the ideal conditions for the development of healthy pregnancy

Profilaxis de sepsis neonatal por Streptococcus Agalactiae (grupo B) basada en vacunas: revisión de la literatura / Prophylaxis of early neonatal sepsis Streptococcus Agalactiae (group B) based on vaccines: literature review

El Streptococcus agalactiae o grupo B (SGB), es el principal agente de sepsis neonatal precoz. A pesar de los intentos de prevención de esta infección, aún no se logra la efectividad esperada. Es por esto que se ha intentado desarrollar una vacuna que pueda prevenir la mayoría de las patologías que esta bacteria produce, incluyendo la sepsis neonatal precoz y tardía. De esta manera se evitarían las limitaciones actuales de la profilaxis antibiótica. Los intentos de crear una vacuna han incluido la utilización de polisacáridos del SGB tanto puros como asociados a proteínas como el toxoide tetánico. También, se han usado proteínas específicas de la cápsula que tienen potencial efectividad como factores inmunogénicos. Las vacunas conjugadas son las más estudiadas en la actualidad, habiendo completado estudios clínicos en fase II, tanto en adultos sanos como en embarazadas. Al ser la sepsis neonatal una complicación grave aún no controlada óptimamente, la creación de una vacuna contra este patógeno sería de gran impacto en salud pública. Se presentan los diferentes tipos de vacunas desarrolladas y el estado de avance en el que se encuentran.

Streptococcus agalactiae or group B, is the mayor causing agent of early onset neonatal sepsis. Although mayor prevention strategies have been made, the expected effectiveness hasn't been achieved. That's why efforts have been made to develop a vaccine that can prevent most of the diseases these bacteria can produce, including early and late onset neonatal sepsis. These way, actual antibiotic prophylaxis limitations can be avoided. Attempts include the utilization of Streptococcus group B polysaccharides in their pure state or combined with proteins as tetanic toxoid. Specific capsule proteins have been used also because of their potential effectiveness as inmunogenic factors. Overall vaccines conjugated ones are the most studied, having completed phase II clinical trials in healthy adults and pregnant women. Neonatal sepsis is a severe complication that has not been controlled yet, so the creation of a vaccine against this pathogen would be of great impact in public health. We introduce now the different developed vaccines and their state of progress.

Vacinas em desenvolvimento: estreptococo do grupo B, herpes-zóster, HIV, malária e dengue / Vaccines under development: group B streptococcus, herpes-zoster, HIV, malaria and dengue

OBJETIVOS: As vacinas contra o estreptococo B, o herpes-zóster, o HIV, a malária e a dengue, selecionadas por critérios de comercialização iminente ou devido a problemas específicos para sua obtenção, foram objeto de uma revisão sobre o estado atual do seu desenvolvimento. FONTE DOS DADOS:Foi realizada revisão da literatura através da MEDLINE no período de 1996 a 2006, sobre a epidemiologia e imunologia das doenças, analisando tanto os maiores problemas para a obtenção de uma vacina como o estado atual dos estudos, com ênfase para os que estavam em fase mais adiantada. SíNTESE DOS DADOS: Cada uma das cinco doenças escolhidas apresenta problemas específicos para o desenvolvimento de uma vacina. No entanto, a maioria deles já foi ou está em vias de ser resolvido, permitindo prever que uma vacina - ou vacinas - eficaz e segura estará disponível em futuro próximo. CONCLUSÕES:Apesar dos problemas enfrentados para o desenvolvimento dessas vacinas, os avanços da biologia molecular e da imunologia permitiram superar a maioria deles, abrindo a perspectiva para a obtenção de novas vacinas.

Recognition of different epitopes on the Ca & R4 proteins of group B streptococci by normal human & antibodies induced in animals.

BACKGROUND & OBJECTIVES: Levels of protective antibodies against Calpha and R4 proteins of the group B streptococci (GBS) have been measured in humans. The findings indicated that the human anti Calpha and anti-R4 antibodies may recognize targets which are different from those recognized by antibodies raised in animals. In the present study normal human serum antibodies which target the GBS proteins Calpha and R4 and immune anti-Calpha and anti -R4 antibodies raised in animals were compared. METHODS: The antigens were prepared by extraction of whole cells of GBS with trypsin and purified, and the testing was done by ELISA and Western blotting. RESULTS: The immune antibodies showed specificity for the corresponding protein and targeted proteins which had been denatured by hot sodium dodecyl sulphate (SDS) or by heating in a nearly neutral buffer. The human antibodies targeted a site(s) common to Calpha and R4 and failed to bind to the denatured proteins. The bulk of antibodies in sera from healthy pregnant women was directed against the SDS and heat labile determinant(s). INTERPRETATION & CONCLUSION: The present results indicated that the immune antibodies were directed against sequential epitopes and the normal human serum antibodies against epitopes determined by molecular conformation.

Rapid diagnosis of vaginal carriage of group B beta haemolytic streptococcus by an enrichment cum antigen detection test.

BACKGROUND & OBJECTIVES: Group B beta haemolytic streptococcus (GBS) is a frequent colonizer of the maternal genital tract causing peripartum fever, puerperal sepsis, neonatal sepsis and neonatal meningitis. The conventional methods for detection of maternal colonization take 24-48 h. We made an attempt to standardize a rapid enrichment cum antigen detection test to screen pregnant women for GBS colonization in less than 8 h, so as to enable early institution of measures to prevent neonatal sepsis. METHODS: Vaginal swabs of 100 women >36 wk of gestation were inoculated onto enrichment broth (Todd Hewitt broth with lysed horse blood and antibiotics). After incubation for 1,2,4,6, and 18 h, the broth was cultured on sheep blood agar. In culture positive cases, the enrichment broth was subjected to antigen detection by latex agglutination test (LAT). For further evaluation of the rapid test, another group of 100 pregnant women were screened for GBS carriage by 6 h enrichment broth culture followed by antigen detection test. RESULTS: Five of the first group yielded GBS on culture and all were positive for GBS antigen after 6 h enrichment. Thirteen of the second group were positive for the antigen, but GBS could be isolated in ten only. This enrichment cum antigen detection test showed sensitivity, specificity, and positive and negative predictive values of 100, 98.4, 83.3 and 100 per cent respectively and could detect as few as 10(3) cfu/ml organisms. Maternal vaginal carriage of GBS was 7.5 per cent (15/200). INTERPRETATION & CONCLUSION: Six hours of enrichment followed by antigen detection proved to be a rapid and reliable method for detection of GBS colonization. This test is easy to perform making it an ideal test for screening GBS vaginal colonization at labour and starting chemoprophylaxis, where indicated on the same day, before the woman is discharged.

Actividad in vitro de agentes antimicrobianos selectos frente a cepas de Neisseria gonorrhoese, streptococcus pneumoniae y streptococcus beta - hemolítico / In vitro activity of selected antimicrobial agents ogeinst of neisseria gonorrhoeae, streftococcus pneumoniae and beta hemolytic streptococcus

Las acividades in vitro de diez agentes antimicrobianos incluyendo a la Penicilina, Ampicilina, Cefalotina, Imipenem, Tetraciclina, Eritromicina, Trimetoprim-Sulfametoxazole, Gentamicina, y un nuevo agente B-lactámico (Imipenem) y dos nuevas quinolonas (Norfloxacina y Ciprofloxacina), fueron comparadas contra 46 cepas de Neisseria gonorrhoeae, 19 cepas de Streptococcus pneumoniae y 16 cepas de Streptococcus B-hemolíticos (especie inepecífica, agrupadas por presentar un número muy pequeño por separado). Todas las cepas fueron aisladas de muestras clínicas recibidas en el laboratorio de Microbiología Clínica del Instituto de Medicina Tropical Alexander Von Humboldt de la Universidad Peruana Cayetano Heredia (Lima-Perú). La susceptibilidad antibacteriana fue estudiada por el método de difusión con disco (antibiograma) y por el método de agar dilución, a través de la determinación de la Concentración Inhibitoria Mínima (CIM). la Penicilina continúa exhibiendo una buena actividad in vitro contra la Neisseria Gonorrhoeae, y puede considerarse a la Cefalotina, al Imipenem y a las 2 fluoroquinolonas (Norfloxacina y Ciprofloxacina) como alternativas de tratamiento. Es necesario resaltar que la no susceptibilidad a la Penicilina se relaciona con la actividad B-lactamasa (mas), en forma significativa (p igual 0.0178). La mayoría de los agentes antimicrobianos presentaron una buena actividad in vitro frente a las cepas de Streptococcus Pneumoniae, exceptuando al Cotrimoxazole, a la Gentamicina y a la Tetraciclina. Se encuentra la aparición de cepas moderadamente susceptibles contra la Penicilina (con un CIM igual a 0.25 ug/ml). Las cepas de Streptococcus B-hemolíticos demostraron la menor susceptibilidad in vitro, siendo sólo susceptibles a los agentes B-lactámicos. En especial, las nuevas quinolonas no han presentado una actividad adecuada frente a estos microorganismos. Se debe promocionar un control periódico de la susceptibilidad antimicrobiana in vitro para detectar rápida y oportunamente la aparición de cepas no susceptibles, y para brindar un nuevo instrumento al médico clínico que lo ayude a tomar las decisiones para brindar el tratamiento más adecuado