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We sought to estimate the impact of maternal HIV testing and prenatal care on the potential to reduce vertical transmission through zidovudine (AZT) use by HIV-infected mothers. We evaluated the prepartum maternal HIV diagnosis rate, prenatal care, disease stage, and vertical transmission rate (from a two-part mixture model) using New York State Medicaid and vital statistics data for HIV-infected mothers and their singletons in 1985-90. We used published data to estimate the effect of AZT on vertical transmission and expert input to define other parameters for the model. Our HIV-infected (N = 1514) had a vertical transmission rate of 27.0%. HIV was diagnosed prepartum for 39.5% of women in 1990. Transmission would have been 22.2% if AZT had been taken only by the subset of women diagnosed prepartum with HIV and receiving prenatal care by 34 weeks gestation (86.7%). Transmission would have dropped to 11.2% if all women had been diagnosed prepartum with HIV and received adequate prenatal care. The observed deficiencies in prenatal care and maternal HIV diagnosis rates in this Medicaid population-based cohort must be addressed to realize the promise of AZT to reduce vertical transmission. 相似文献
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VA Tyurin YY Tyurina PJ Quinn NF Schor R Balachandran BW Day VE Kagan 《Canadian Metallurgical Quarterly》1998,60(2):270-281
Incubation of mock-transfected PC12 rat pheochromocytoma cells (PC12) for 2 h with increasing concentrations of glutamate caused progressive loss of viability (e.g., 67% with 15 mM glutamate). In contrast, the viability of bcl-2-transfected cells (PC12/bcl-2) was unaffected by glutamate. Neither PC12 nor PC12/bcl-2 cells showed a significant incidence of apoptosis in response to glutamate. Conventional phospholipid analysis by high-performance TLC and phosphorous determination showed no significant changes in the phospholipid composition of either cell line incubated with =15 mM glutamate. Phospholipid peroxidation was quantified in the cells using our newly developed method based on fluorescence-HPLC analysis of metabolically incorporated oxidation-sensitive and fluorescent fatty acid, cis-parinaric acid. Unlike previous studies that measured total phospholipid oxidation, this novel technology permitted quantitation of oxidative stress in different classes of labeled phospholipids (the amount of labeled phospholipids in the cells did not exceed 1% of total phospholipids). Significant peroxidation of phosphatidylcholine and phosphatidylethanolamine occurred in PC12 cells treated with >5 mM glutamate. The peroxyl radical initiator 2,2'-azobis(2,4-dimethylvaleronitrile) caused a pronounced loss of all major phospholipid classes in PC12 cells, but no loss of cell viability. No phospholipid peroxidation was detected in PC12/bcl-2 cells incubated with =15 mM glutamate or with 2, 2'-azobis(2,4-dimethylvaleronitrile). These results directly demonstrate that peroxidation of membrane phospholipids is not responsible for the cytotoxicity of glutamate in PC12 cells. Total cellular thiol, protein thiol and GSH reserves were quantified by a previously described electron paramagnetic resonance spectrometric method. Total thiols were ca. 1.5-fold greater in PC12/bcl-2 than in PC12 cells. Glutamate (=5 mM) caused a progressive and equally significant decrease in total thiols and GSH in both PC12 and PC12/bcl-2 cells. High glutamate concentrations caused oxidation of protein sulfhydryls in PC12 cells, but not in PC12/bcl-2 cells. The results suggest that the changes in cellular milieu caused by bcl-2 gene transfection protect PC12 cells from the toxic effects of glutamate in a manner consistent with prevention of protein sulfhydryl oxidation. 相似文献
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Prevention by nerve growth factor (NGF) of apoptotic death in neural cells has been variously ascribed to binding of NGF to its low-affinity (p75) or high-affinity (trkA) receptor or to a cooperative interaction between the two. In a series of studies using, in turn, neuroblastoma cell lines that express only p75, mutant NGF species that bind selectively to either p75 or trkA, and a polyclonal antibody that binds to the NGF-binding domain of p75, we demonstrate that NGF binding to p75 is both necessary and sufficient for the abrogation of apoptosis in neuroblastoma cells treated with antimitotic agents. 相似文献
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KS Ternovo? TN Selezneva AV Akleev IA Pashkov LA Noskin NV Klopov VA Noskin NF Starodub 《Canadian Metallurgical Quarterly》1998,70(3):81-85
The effects of an alternative chelation program in thalassemic patients with severe iron overload are investigated. The schedule of treatment, feasible at home, consists in the administration of deferoxamine intravenously (100 mg/kg/die 8 hours 10 days a month), followed by 50 mg/kg/die subcutaneously in the remaining 20 days of the month. The results in 34 patients who underwent this program over 8 months are reported. After intensive chelation therapy serum ferritin and transaminase levels were significantly lower, and daily urinary iron excretion values were significantly higher when compared to the levels observed before the treatment. After the period of study, echocardiography revealed an ejection fraction (EF) significantly higher in 15 out of 34 cardiopathic patients. In conclusion, the alternative chelation program is effective in reducing iron overload of thalassemic patients, protecting them also against cardiac disease. 相似文献