Enzyme-linked immunosorbent assay for IgA antibodies to Trypanosoma cruzi in congenital infection.
(73/48457)
With the aim of achieving earlier diagnosis of congenital Trypanosoma cruzi infection, we assessed the usefulness of detecting specific IgA antibody by an ELISA. We evaluated 12 pregnant women chronically infected with T. cruzi, their newborn infants, and three additional neonates with parasitemia at birth. The IgA-specific antibody was detected by adapting the procedure for use of a commercial IgG ELISA, the Hemagen Chagas' Kit (Hemagen Diagnostics, Inc., Waltham, MA). Trypanosoma cruzi-specific IgA was detected in 10 (83%) of 12 mothers at delivery, in one of three parasitemic infants, and one of 12 newborns of the chronically infected women. Testing of 13 infants at six months of age revealed IgA in seven infants (54%), of whom four also had persistent T. cruzi-specific IgG. Detection of T. cruzi-specific IgA could provide a criterion for diagnosis of congenital infection in the absence of detectable parasitemia. (+info)
Prevalence of enteric hepatitis A and E viruses in the Mekong River delta region of Vietnam.
(74/48457)
A study of antibody prevalence for hepatitis A virus (HAV) and hepatitis E virus (HEV) was carried out in southwestern Vietnam in an area adjacent to a known focus of epidemic HEV transmission. The purpose of this investigation was first to provide a prevalence measure of hepatitis infections, and second to determine the outbreak potential of HEV as a function of the susceptible population. Blood specimens collected from 646 persons in randomly selected village hamlets were examined by an ELISA for anti-HEV IgG and anti-HAV IgG. The prevalences of anti-HEV IgG and anti-HAV IgG were 9% and 97%, respectively. There was a significant increase (P < 0.01) in age-specific anti-HEV IgG. A notable increase in anti-HAV IgG prevalence (P < 0.0001) occurred between child populations 0-4 (64%) and 5-9 (95%) years of age. No evidence of familial clustering of anti-HEV IgG-positive individuals was detected, and household crowding was not associated with the spread of HEV. Boiling of water was found to be of protective value against HEV transmission. A relatively low prevalence of anti-HEV indicates considerable HEV outbreak potential, against a background of 1) poor, water-related hygiene/sanitation, 2) dependence on a (likely human/animal waste)-contaminated Mekong riverine system, and 3) periodic river flooding. (+info)
Insurance coverage of unintended pregnancies resulting in live-born infants--Florida, Georgia, Oklahoma, and South Carolina, 1996.
(75/48457)
In the United States during 1994, approximately 49% of all pregnancies, excluding miscarriages, were unintended. Unintended pregnancy can result in adverse health outcomes that affect the mother, infant, and family. Little is known about the distribution of unintended pregnancy with respect to the payment source for health care. In the absence of data for periconceptional payment source for health care, prenatal-care payment source is used as a surrogate. To develop recommendations to reduce unintended pregnancy, CDC analyzed insurance coverage-specific prevalences of live-born infants from unintended pregnancies among women aged 20-34 years using data from the Pregnancy Risk Assessment and Monitoring System (PRAMS) for 1996 (the most recent year for which data are available). This report summarizes the results of this analysis, which indicates that the highest rates of unintended pregnancy occurred among women covered by Medicaid, with lower rates among women covered by health-maintenance organizations (HMOs) or private insurance. (+info)
Two neutralizing human anti-RSV antibodies: cloning, expression, and characterization.
(76/48457)
BACKGROUND: Respiratory syncytial virus (RSV) infection is a major problem in the newborn and aging populations. Fully human monoclonal antibodies with the ability to neutralize RSV could have a major impact on the immunotherapy of the disease. The generation of human antibodies has been difficult because there exists no general way to activate B cells against an antigen of choice in vitro. MATERIALS AND METHODS: Human spleen cells from individuals exposed to RSV were used to repopulate SCID mice. Hu-SCID mice were boosted with RSV fusion (F)-protein and subsequently developed B cell tumors. The tumors were removed and cultured and subcloned in vitro, using a feeder layer of CD154-expressing T cells. Two of these tumors produced the antibodies designated RF-1 and RF-2. VL genes were isolated by standard PCR techniques, however, it was necessary to use high-temperature reverse transcriptase to clone the VH genes. RESULTS: RF-1 and RF-2 VH genes were both found to be closely related members of the VH2 family. Vk genes originated from the VK III family. RF-1 and RF-2 recombinant antibodies expressed in CHO cells (cRF-1 and cRF-2) were found to have affinities for RSV F-protein of 0.1 nM and 0.07 nM, respectively, and both were able to neutralize several A and B subtypes of RSV. CONCLUSION: The technique of immortalizing human B lymphocytes, by passage in SCID mice and expression as recombinant antibodies in CHO cells, provides a method by which high-affinity human antibodies can be developed for immunotherapy of viral diseases. (+info)
Artificial reconstituted pulmonary surfactant in prevention and treatment of respiratory distress syndrome in neonates.
(77/48457)
AIM: To test an artificial reconstituted pulmonary surfactant (APS) for prevention and treatment of respiratory distress syndrome (RDS). METHODS: A membrane-formed method combined with supersonic dispersing was used to prepare APS. A pulsating bubble surface tension measurement was established to compare surface properties of APS with natural pulmonary surfactant (NPS). A preliminary clinical trial was made for prevention and treatment of RDS. RESULTS: The APS reduced surface tension from 44.0 mN/m to < 1.0 mN/m in vitro. The changes of APS lipid contents were < 5% of labeled content at 37 degrees C. Clinical trial showed that the APS prevented RDS in 20/20 and cured RDS in 2/2 premature neonates. CONCLUSION: The APS had good surface properties similar to NPS. (+info)
Serum albumin inhibits echovirus 7 uncoating.
(78/48457)
Echoviruses induce a wide spectrum of diseases in man, the most severe being meningitis. In neonates, however, a severe systemic infection can be observed, leading to death. Serum albumin is the most abundant protein in plasma and most interstitial fluids, and its functions include osmoregulation and transport and delivery of hydrophobic molecules such as fatty acids and steroids. The results of cold-synchronized one-step growth analysis of echovirus 7 infection and sucrose-gradient analysis of A-particles suggest that physiological concentrations of albumin block echovirus 7 infection by inhibiting uncoating. The blockage was reversible and was still effective when albumin was added 30 min after virus adsorption. Inhibition of uncoating was confirmed by using rhodanine, a known specific inhibitor of echovirus uncoating. After removal of the albumin blockage, addition of rhodanine perpetuated the inhibition. Serum and interstitial albumin concentrations may limit echovirus infection in vivo and thereby act as an extracellular determinant for echovirus tropism. (+info)
Comparison of urinary 6beta-hydroxycortisol/cortisol ratio between neonates and their mothers.
(79/48457)
AIMS: To assess CYP3A enzyme activity in human neonates by measuring the urinary 6beta-hydroxycortisol/cortisol (6beta-OHF/C) ratio. METHODS: Fifty-six mature male neonates with normal delivery, seventeen of their mothers and twenty-four healthy non-pregnant young women participated in this study. Urinary 6beta-OHF/C ratio was determined on the day of birth in neonates and their mothers. In addition, changes in the ratio after birth were determined in neonates. RESULTS: On the day of birth, the urinary 6beta-OHF/C ratio of neonates was significantly higher than that of their mothers (20.5 vs 6.9). In contrast, no significant difference was observed in the mean ratio of urinary 6beta-OHF/C between women with and without pregnancy (6.9 vs 9.0). The urinary 6beta-OHF/C ratio after birth was decreased day by day in neonates. CONCLUSION: These results indicate that the high urinary 6beta-OHF/C ratio in mature neonates on the day of birth is independent of the activity of CYP3A enzyme in their mothers. (+info)
Concordant induction of cyclin E and p21cip1 in differentiated keratinocytes by the human papillomavirus E7 protein inhibits cellular and viral DNA synthesis.
(80/48457)
Productive infections by human papillomaviruses (HPVs) occur only in differentiated keratinocytes in squamous epithelia in which the HPV E7 protein reactivates the host DNA replication machinery to support viral DNA replication. In a fraction of the differentiated keratinocytes, E7 also posttranscriptionally induces p21Cip1, which is distributed in a mutually exclusive manner with unscheduled cellular DNA synthesis. In this study, double immunofluorescence labeling unexpectedly revealed that E7 caused a concordant accumulation of both cyclin E and p21Cip1 to high levels in patient papillomas and in organotypic cultures of primary human keratinocytes. The induction of cyclin E is mutually exclusive with unscheduled cellular DNA synthesis or abundant viral DNA. These novel virus-host interactions in differentiated keratinocytes are in contrast to previous observations made in submerged proliferating cultures, in which HPV E7 induces cyclin E and overcomes p21Cip1 inhibition of S-phase entry. We propose that an appropriately timed induction of cyclin E/cyclin-dependent kinase 2 by HPV E7 in postmitotic cells enables S-phase reentry and HPV DNA amplification, whereas prematurely induced cyclin E stabilizes p21Cip1 protein, which then inhibits cyclin E/cyclin-dependent kinase 2. Consequently, cyclin E and p21Cip1 both fail to turn over, and DNA synthesis does not occur. (+info)