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OBJETIVO: Realizar revisao sobre os principais aspectos do desenvolvimento imunologico fetal, salientando a defesa de prematuros extremos contra patogenos bacterianos e descrevendo a situacao atual de intervencoes imunoterapeuticas para a prevencao de sepse hospitalar. FONTES DOS DADOS: Obtiveram-se, por meio de busca eletronica, no banco de dados MEDLINE, artigos publicados nos ultimos 15 anos referentes ao tema, e foram selecionados aqueles que trouxessem informacoes relevantes. SINTESE DOS DADOS: A imunidade de prematuros extremos e deficiente devido a fragilidade da pele, a carencia dos produtos de ativacao do sistema complemento, ao menor pool de reserva de precursores de neutrofilos na medula ossea e a quimiotaxia, aderencia, deformabilidade e atividade enzimatica neutrofilicas reduzidas. Limitacoes adicionais sao detectadas na citotoxicidade de celulas NK, na proliferacao e producao de citocinas dos linfocitos T, na cooperacao entre celulas T e B e na sintese de anticorpos pelos linfocitos B. Ainda nao foram demonstrados beneficios definitivos de intervencoes para incremento da funcao imunologica dessas criancas, tais como o uso de imunoglobulinas endovenosas e de fatores estimuladores de colonias mieloides. CONCLUSAO: Em consequencia a imaturidade de diversos componentes da imunidade, prematuros extremos sao altamente suscetiveis a infeccoes nosocomiais. As possibilidades ainda muito limitadas para a intervencao nesse sistema fazem com que o controle dos fatores extrinsecos sejam essenciais para a prevencao da sepse nosocomial nessas criancas.

PURPOSE: to investigate the effect of antiretroviral drugs on carbohydrate metabolism in HIV-infected pregnant women and on fetal and neonatal prognosis. METHODS: a prospective study was conducted on 57 pregnant women. The women were divided into three groups: ZDV group, taking zidovudine (n=20), TT group, taking zidovudine + lamivudine + nelfinavir (n=25), and control group (n=12). Blood samples were obtained for the determination of the area under the curve (AUC) after a 75-g oral glucose test at four periods during pregnancy (1st=14-20 weeks, 2nd= 21-26 weeks, 3rd=27-32 weeks and 4th=33-38 weeks). Perinatal prognosis was based on prematurity rates, intrauterine growth restriction (IUGR), low birth weight, perinatal mortality, and vertical HIV-1 transmission. Data were analyzed statistically using the nonparametric c2 test, Friedman test and Kruskal-Wallis test. RESULTS: the median values of the AUC were 11.685 mg/dL for the control group, 13.477 mg/dL for the ZDV Group, and 13.650 mg/dL for the TT group (p=0.049). The antiretroviral agents had no deleterious effects on prematurity, low birth weight, IUGR rates or on Apgar score. There was no case of vertical transmission of HIV-1. CONCLUSIONS: an association was detected between the use of triple therapy and the development of carbohydrate intolerance during pregnancy. This association was not shown with ZDV alone. The antiretroviral agents had no deleterious effects on perinatal prognosis.

OBJETIVO: avaliar os efeitos de drogas anti-retrovirais isoladas e em associação sobre as taxas de fertilidade em ratas prenhes expostas a estes fármacos, bem como o efeito perinatal nas crias. MÉTODOS: foram utilizadas ratas fêmeas prenhes adultas da raça Wistar, pesando inicialmente entre 200 e 230 g. Foram testadas a azidotimidina (AZT), lamivudina (3TC) e nelfinavir (NFV), cujas dosagens foram padronizadas em 10 vezes a dose normalmente utilizada em gestantes, proporcionalmente ao peso dos animais. No total foram avaliados sete grupos, incluindo o controle. O início da experimentação foi o dia zero da prenhez e as cesarianas foram realizadas com 21 dias de prenhez. Para o cálculo das taxas de fertilidade, avaliaram-se o número de fetos vivos e mortos, sítios de implantação e número de corpos lúteos. Utilizaram-se o teste t de Student e Mann-Whitney para a análise estatística. RESULTADOS: não houve alterações significativas nas taxas de perdas pré-implantação e da eficiência de implantação de ratas tratadas com anti-retrovirais isolados e em associação. No entanto, houve aumento significativo nas taxas de perdas pós-implantação (grupo controle: 7,6%; grupos medicamentos: de 20,2 a 26,7%), redução significativa nas taxas de viabilidade fetal (grupo controle: 92,4%; grupos medicamentos: de 73,3 a 79,8%) e redução significativa no número de fetos por ninhada (grupo controle: 14,7, grupos medicamentos: de 11,1 a 12,7). Observou-se também que houve redução do peso materno e dos fetos nos grupos tratados com 3TC, AZT + 3TC e AZT + 3TC + NFV. CONCLUSÃO: com a utilização de doses elevadas de medicamentos anti-retrovirais na presente casuística, efeitos importantes sobre a fertilidade foram encontrados, o que sinaliza para a necessidade de se pesquisarem outros fármacos anti-retrovirais com menor potencial histotóxico e que possam, com segurança, ser utilizados por gestantes portadoras da infecção pelo vírus da imunodeficiência humana. PURPOSE: to evaluate experimentally the effects of antiretroviral drugs used alone and in association upon the fertility of pregnant Wistar rats and the perinatal effects on the offspring. METHODS: adult female pregnant Wistar rats weighing 200-230 g were used. The antiretroviral drugs zidovudine (AZT), lamivudine (3TC) and nelfinavir (NFV) were used alone and in association at daily doses of ten times the dose normally used in pregnant women, proportionally to the animal's body weight. Seven groups were studied, including the control one. The experiment started on day 0 and the pregnant animals were sacrificed on day 21. The alive and dead fetuses, the total implantation sites and the total numbers of corporea lutea were used to calculate the fertility values. The statistical analysis was performed by Student's t test and by the Mann-Whitney test. RESULTS: there were no significant statistical differences regarding preimplantation loss and implantation efficiency values of the rats treated with isolated and associated antiretroviral drugs. There was a significant increase in the postimplantation loss values (control group: 7.6%; drug groups variation: 20.2-26.7%), a decrease in the fetal viability values (control group: 92.4%, drug groups variation: 73.3-79.8%), and a decreasing number of fetuses per animal (control group: 14.7; drug groups variation: 11.1-12.7). There was a significant weight reduction of the female rats and of the offspring of animals treated with 3TC, AZT + 3TC and AZT + 3TC + NFV. CONCLUSION: with the administration of high antiretroviral doses, important fertility effects could be observed, which showed that less histotoxic antiretroviral drugs must be studied in order to warrant the safety of using these medicines in pregnant HIV-1 - infected women.

The work reported here points up the real benefits provided by neonatal immunoprophylaxis of newborns delivered by mothers who are seropositive for the hepatitis B virus surface antigen HBsAg and underscores the need to properly identify such mothers in Brazil so that immunoprophylaxis can be undertaken. To help determine levels of hepatitis B virus (HBV) infection and seropositivity for various HBV markers among pregnant women in Southeast Brazil, investigators studied 7992 pregnant women delivering at the Clinical Hospital of the University of Sao Paulo's Ribeirao Preto School of Medicine in Ribeirao Preto, Brazil. Seroreactivity for HBsAg was determined first by serologic screening with an enzyme-linked immunosorbent assay (ELISA) procedure in which the sera were incubated for 2 hours and then by confirmation with another ELISA in which the sera were incubated for 18 hours. Subsequently, tests for anti-HBsAg, HBeAg, anti-HBeAg, and anti-HBcAg markers were conducted using confirmed positive samples. Initial screening found 84 of the 7992 samples (1.05%, 95% CI: 0.84-1.30) to be positive for HBsAg; however, this HBsAg positivity was confirmed in only 76 (0.95%, 95% CI: 0.75-1.19). The positivity rate was significantly higher among subjects whose pregnancies terminated in miscarriage (1.84%) than among those with live births (0.83%) (chi2, Yates correction = 7.6; P = 0.005). Anamnesis was able to identify HBV risk factors in only 27.6% of the confirmed HBsAg-positive subjects or close household contacts. However, 21.3% (95% CI: 1.04-30.56) of the confirmed HBsAg-positive subjects were found positive for HBeAg, indicating a high risk of vertical transmission of the virus. These results demonstrate a need to conduct specific serologic research at term, in order to provide effective neonatal immunoprophylactic benefits.