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71.
Reproductive outcomes were investigated in black and white female college graduates, presumed to be of similar socioeconomic status and similar risk profile with respect to environmental factors. Data were gathered by mail survey from graduates (1973-1985) of four Atlanta, Georgia, colleges between February and June 1988. Of 6,867 alumnae to whom questionnaires were mailed, 3,084 responded. A follow-up study of black nonrespondents yielded responses from 14% (335) of those who did not respond to the mail survey. For all graduates with a first live born at the time of survey (n = 1,089), the rates of preterm delivery, low birth weight, and infant mortality were 80.8, 82.6, and 14.6 per thousand births (primigravida), respectively. Compared with white graduates, black graduates had 1.67 times the risk of preterm delivery and 2.48 times the risk of low birth weight. Measures of social and economic status differed significantly by race. However, adjustment for these variables did not reduce the estimated risk for black graduates compared with whites. Analysis of the nonresponder survey suggested that respondent data alone overestimates the incidence of adverse outcomes in blacks; using nonresponder data, relative risks of 1.28 (preterm delivery) and 1.75 (low birth weight) were calculated as lower limits of the increased risk for blacks.  相似文献   
72.

BACKGROUND

Anaphylaxis is a serious and growing concern in the school setting as the prevalence of food allergies and food‐induced severe allergic reactions continues to increase.

METHODS

A cross‐sectional, web‐based survey was conducted regarding anaphylactic events that occurred during the 2014‐2015 school year. Eligible schools were enrolled in the EPIPEN4SCHOOLS® program (Mylan Specialty L.P., Canonsburg, PA), which provides free epinephrine auto‐injectors to qualifying US schools. Participating schools completed a 29‐item survey on anaphylactic event occurrence and treatment, epinephrine stock, school policies regarding anaphylaxis, school staff training, and school nursing coverage.

RESULTS

Responses were provided by 12,275 schools. Epinephrine was administered on school property for 63.7% of reported anaphylactic events (1272/1998). In 38.5% (235/610) of events for which epinephrine was not used, antihistamines were cited as the reason. Only 59.4% of schools cited epinephrine as their standard first‐line therapy for anaphylaxis. School nurses were most likely to be trained in anaphylaxis recognition and permitted to administer epinephrine; however, just 53.6% of schools had a full‐time nurse on staff.

CONCLUSIONS

Process‐related barriers to the appropriate use of epinephrine go beyond access to medication. Widespread staff training and review of school policies are needed to ensure that anaphylaxis is appropriately managed in schools.
  相似文献   
73.
Tumor necrosis factor (TNF) has been proposed as an important mediator of the inflammatory response in acute lung injury. To better understand polymorphonuclear leukocyte (PMN) activation during acute lung injury, we evaluated the effects of TNF on several in vitro PMN functions, including chemotaxis, chemiluminescence, and elastase activity. In the chemotaxis assay using a modified Boyden chamber, TNF alone or with N-formyl-methionyl-leucyl-phenylalanine (FMLP, 10(-8) mol/L) did not alter PMN migration. TNF suspended with 1% zymosan-activated serum (ZAS) increased PMN migration at low concentrations and decreased migration at high concentrations (control 99 +/- 4.8 microns, n = 9; TNF 0.1 ng/ml 135 +/- 9.4 microns, n = 5, p less than 0.01; TNF 1000 ng/ml 62 +/- 7.5 microns, n = 5, p less than 0.01). In the chemiluminescence assay, TNF (1000 ng/ml) induced a 3-fold increase in the PMN chemiluminescent response. However, TNF incubated with PMN did not cause an increase in supernatant elastase activity. These data reveal TNF induced the production of PMN reactive oxygen species as evidenced by an increased chemiluminescent response. Whereas TNF increased chemotaxis at low concentrations in the presence of 1% ZAS, high concentrations of TNF similar to levels detected in septic shock caused a decrease in chemotaxis that might contribute to retaining PMN in sites of inflammation. It is thus suggested that TNF may contribute to inflammation by stimulating the production of PMN-reactive oxygen species and modulating-PMN chemotaxis.  相似文献   
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Substance use and depression are prevalent among mothers enrolled in home visiting programs and are significant risk factors for child maltreatment, yet most home visiting programs are staffed by workers who lack the training and clinical skills to address these risks. Emanating from one state network's interest in advancing its practice in this area, the current study surveyed 159 home visitors on their current practices, training, knowledge, and perceived self‐efficacy, and perceived system‐ and client‐level barriers regarding client substance use and depression. Home visitors reported managing maternal depression more extensively than substance use, though overall management of both risk areas was low. More training was associated with more extensive management of both risk domains, as was greater home visitor knowledge and self‐efficacy. Implications for the development of strategies to improve home visitor management of client behavioral health risks, including enhanced skills‐based training and supervision, are discussed.  相似文献   
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Short inter-pregnancy intervals (IPIs) have been associated with adverse maternal and infant health outcomes in the literature. However, many studies in this area have been lacking in quality and appropriate control for confounders known to be associated with both short IPIs and poor outcomes. The objective of this systematic review was to assess this relationship using more rigorous criteria, based on GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology. We found too few higher-quality studies of the impact of IPIs (measured as the time between the birth of a previous child and conception of the next child) on maternal health to reach conclusions about maternal nutrition, morbidity or mortality. However, the evidence for infant effects justified meta-analyses. We found significant impacts of short IPIs for extreme preterm birth [<6 m adjusted odds ratio (aOR): 1.58 [95% confidence interval (CI) 1.40, 1.78], 6-11 m aOR: 1.23 [1.03, 1.46]], moderate preterm birth (<6 m aOR: 1.41 [1.20, 1.65], 6-11 m aOR: 1.09 [1.01, 1.18]), low birthweight (<6 m aOR: 1.44 [1.30, 1.61], 6-11 m aOR: 1.12 [1.08, 1.17]), stillbirth (aOR: 1.35 [1.07, 1.71] and early neonatal death (aOR: 1.29 [1.02, 1.64]) outcomes largely in high- and moderate-income countries. It is likely these effects would be greater in settings with poorer maternal health and nutrition. Future research in these settings is recommended. This is particularly important in developing countries, where often the pattern is to start childbearing at a young age, have all desired children quickly and then control fertility through permanent contraception, thereby contracting women's fertile years and potentially increasing their exposure to the ill effects of very short IPIs.  相似文献   
80.
We have previously described a unique type of delta beta-thalassemia in a Chinese family characterized by increased expression of the G gamma and A gamma fetal globin genes in the absence of a large deletion in the beta-globlin gene cluster. Our earlier study of the beta-globin gene on this delta beta-thalassemia chromosome showed a promoter mutation in the TATA box. In this report, we describe the results of our study of the fetal globin domain of this delta beta-thalassemia chromosome. We have cloned a 13-kb DNA fragment that includes the G gamma and the A gamma genes and the 3' A gamma enhancer element of this delta beta-thalassemia chromosome. DNA sequence analysis of the G gamma and A gamma-globin genes including their promoters did not show any mutations, but analysis of the putative enhancer element downstream from the A gamma-globin gene showed a C to T substitution 2,401 nucleotides downstream from the A gamma cap site. We performed DNA linkage analysis to determine if this mutation is unique to this chromosome or represents a common polymorphism. Our linkage analysis showed that this mutation is not a common polymorphism and that it is also not an intrinsic part of the haplotype of the chromosome on which it was found. We also studied the interaction of nuclear proteins from erythroid and nonerythroid cells with the DNA sequences surrounding this mutation. We have shown by in vitro DNase I footprinting that this mutation falls within a region that is occupied by a novel DNA-binding protein that binds to this site in nuclear extracts from erythroid, but not nonerythroid cells. The binding of this nuclear protein to DNA appears to be dependent on GATA-1 binding to an adjacent GATA-1 site. We have also developed a new functional assay to compare the activity of the normal and mutant A gamma enhancer elements in erythroid cells. Analysis of the activity of the mutant enhancer shows that the mutation completely eliminates all enhancer activity in this assay. These findings suggest that this mutation of the A gamma enhancer on a chromosome that carries a partially inactivated beta-globin gene may be responsible for the increased expression of both gamma-globin genes seen in this condition.  相似文献   
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