Assuntos

RESUMO

OBJECTIVE: The goal of this study was to examine associations between demographic, behavioral, and clinical variables and mother-to-child HIV transmission in 15 US jurisdictions for birth years 2005 through 2008. METHODS: The study used Enhanced Perinatal Surveillance system data for HIV-infected women who gave birth to live infants. Multivariable logistic regression was used to assess variables associated with mother-to-child transmission. RESULTS: Among 8054 births, 179 infants (2.2%) were diagnosed with HIV infection. Half of the births had at least 1 missed prevention opportunity: 74.3% of infected infants, 52.1% of uninfected infants. Among 7757 mother-infant pairs with sufficient data for analysis, the odds of having an HIV-infected infant were higher for women who received late testing or no prenatal antiretroviral medications (odds ratio: 2.5 [95% confidence interval (CI): 1.5-4.0] and 3.5 [95% CI: 2.0-6.4], respectively). The odds for mothers who breastfed were 4.6 times (95% CI: 2.2-9.8) the odds for those who did not breastfeed. The adjusted odds for women with CD4 counts <200 cells per microliter were 2.4 times (95% CI: 1.4-4.2) those for women with CD4 counts ≥500 cells per microliter. The odds for women who abused substances were twice (95% CI: 1.4-2.9) those for women who did not. CONCLUSIONS: The odds of having an HIV-infected infant were higher among HIV-infected women who were tested late, had no antiretroviral medications, abused substances, breastfed, or had lower CD4 cell counts. Increases in earlier HIV diagnosis, substance abuse treatment, avoidance of breastfeeding, and use of prenatal antiretroviral medications are critical in eliminating perinatal HIV infections in the United States.

Assuntos

RESUMO

We enrolled 61 neonates of 600 to 1250 gm birth weight with evidence of low-grade intraventricular hemorrhage at 6 to 11 hours of age in a prospective, randomized, placebo-controlled trial to test the hypothesis that indomethacin (0.1 mg/kg given intravenously at 6 to 12 postnatal hours and every 24 hours for two more doses) would prevent extension of intraventricular hemorrhage. Twenty-seven infants were assigned to receive indomethacin; 34 infants received saline placebo. There were no significant differences between the two groups in birth weight, gestational age, sex, Apgar scores, percentage of infants treated with surfactant, or distribution of hemorrhages at the time of the first cranial sonogram (echo-encephalogram). Within the first 5 days, 9 of 27 indomethacin-treated and 12 of 34 saline solution-treated infants had extension of their initial intraventricular hemorrhage (p = 1.00). Four indomethacin-treated and three saline solution-treated infants had parenchymal extension of the hemorrhage. Indomethacin was associated with closure of a patent ductus arteriosus by the fifth day of life (p = 0.003). There were no differences in adverse events attributed to indomethacin. We conclude that in very low birth weight infants with low grade intraventricular hemorrhage within the first 6 postnatal hours, prophylactic indomethacin therapy promotes closure of the patent ductus arteriosus and is not associated with adverse events, but does not affect the cascade of events leading to parenchymal involvement of intracranial hemorrhage.

Assuntos

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Because earlier studies suggested that preterm infants with germinal matrix hemorrhage or intraventricular hemorrhage or both (GMH/IVH) present within the first 12 postnatal hours are at greatest risk for the development of high-grade hemorrhage and neurodevelopmental disability, we examined the risk factors for this insult among 229 neonates of 600 to 1250 gm birth weight in a multicenter study. All had echoencephalography (ECHO) within the first 11 hours and serially for the next 20 days; risk factor data were collected prospectively. Forty-three infants had GMH/IVH within the first 5 to 11 hours (mean age at ECHO 7.7 hours): 18 GMH and 21 grade II, 1 grade III, and 3 grade IV IVH. One hundred eighty-six infants did not have GMH/IVH at a mean age of 7.9 hours. Both groups of infants were similar in birth weight, gestational age, maternal risk factors, cord pH values, and surfactant therapy before ECHO. The group with early IVH had more vertex presentations than the group without early IVH (79% vs 55%, p = 0.043), less maternal tocolytic use (42% vs 60%, p = 0.029), and more vaginal deliveries (67% vs 44%, p = 0.005). In the first 21 days, severe IVH developed in 12 infants with early IVH and in 6 infants without early IVH (p < 0.001). There were more neonatal deaths (16% vs 6%, p = 0.035) and more deaths at any time during the primary hospitalization (23% vs 9%, p = 0.010) among the early IVH group than among the group without early IVH. Multivariate analysis indicated that the mode of delivery, fetal presentation, and birth weight were important and independent prognostic indicators of IVH.

Assuntos

RESUMO

The distribution and the kinetics of potentiated antibody synthesis have been studied at the cellular level in rats infested with Nippostrongylus brasiliensis using the homologous adoptive cutaneous anaphylaxis technique. In animals immunized in the hind footpads with alum-absorbed ovalbumin 10 days prior to infestation with the parasite, the major sites of potentiated anti-ovalbumin homocytotropic antibody synthesis were the regional lymph nodes of the gut and the lungs. Peyer's patches were weakly active late in the response and the spleen produced considerable amounts of potentiated antibody. The regional lymph nodes of the ovalbumin immunization sites were the only organs in which specific homocytotropic antibody synthesis was detected in uninfested control rats. The kinetics of synthesis of the potentiated antibody by cells correlated well with the levels of anti-ovalbumin IgE antibodies in the sera of the infested rats. A traffic of cells secreting anti-ovalbumin homocytotropic antibody was detected in the thoracic duct lymph, but not the mesenteric lymph of immunized uninfested rats. After infestation, the mesenteric lymph also contained cells secreting potentiated antibody. The mesenteric lymph is a major route by which IgE and potentiated IgE antibodies reach the circulation in infested rats. The possible mechanisms responsible for the effects of the parasite on antibody secretion in distant lymphoid organs are discussed.

Assuntos

RESUMO

Mesenteric lymphadenectomy caused a marked reduction in the amounts of both parasite-specific and total IgE in the serum of Nippostrongylus brasiliensis infested rats. This was accompanied by reduced quantities of IgE in the thoracic duct lymph, showing that the mesenteric lymph node is of great importance in the generation of the elevated IgE levels which accompany this infestation. Conversely, the intestinal lamina propria and the Peyer's patches did not appear to be significant contributors to either thoracic duct lymph or serum IgE levels. Homocytotropic antibody-secreting cells specific for parasite antigens were detected in the thoracic duct lymph of lymphadenectomized rats and are believed to arise directly from the gut mucosa and possibly from Peyer's patches.

Assuntos

RESUMO

Synthesis of specific homocytotropic antibody by cells from various lymphoid and haemopoietic organs in rats infested with Nippostrongylus brasiliensis has been studied by use of homologous adoptive cutaneous anaphylaxis and compared with the kinetics of appearance in the serum and thoracic duct lymph of specific IgE antibodies. Using this technique, synthesis of specific mast cell-sensitizing antibody has been detected in the draining lymph nodes of the lung as early as 12 days after infestation and by 14 days in the draining lymph nodes of the small intestine. Specific IgE antibody was not detected in serum until between 16 and 18 days after infestation. The delay in detection of antibody in the serum is at least in part due to its rapid removal from the blood, because antibody en route to the bloodstream from the gut-associated lymphoid tissue was detected in the thoracic duct lymph plasma as early as day 12. A major traffic of homocytotropic antibody-secreting cells has been detected in the thoracic duct lymph of the infested rats. The results are discussed in terms of the possible role of immediate hypersensitivity in the expulsion of the parasite, the origin of the IgE antibody response to the parasite and the mechanism of the potentiated reagin response.

Assuntos

RESUMO

A prospective study of 48 infants with periventricular-intraventricular hemorrhage was carried out to evaluate the role of daily lumbar punctures, instituted from the time of diagnosis of the hemorrhage, in prevention of posthemorrhagic hydrocephalus and improvement in immediate outcome. The data lead to the following conclusions: (1) minor hemorrhage (Grade I) is associated with minimal risk of death or hydrocephalus; (2) moderate hemorrhage (Grade II) is associated with low risk of death and intermediate risk of hydrocephalus, and serial lumbar punctures do not reduce these risks; and (3) severe hemorrhage (Grade III) is associated with high risks of death or hydrocephalus or both, and serial lumbar punctures also do not reduce these risks.

Assuntos

RESUMO

Forty-four haemagglutinating viruses were isolated from the pooled tracheal/cloacal swabs of the dead birds from 170 consignments of caged birds arriving at Heathrow Airport over a period of 6 months. Two isolates were identified as Newcastle disease virus but the remaining 42 were all identified as influenza viruses with Hav 7 Neq 2 antigens. All the consignments from which influenza viruses were isolated originated in India but had widespread destinations. The NDV isolates were from birds originating in central America and destined for Japan.

Assuntos