Enzymes and reproduction in natural populations of Drosophila euronotus.
Populations of Drosophila euronotus, one from southern Louisiana )3 samples), and one from Missouri (2 samples), were classified for allele frequencies at alkaline phosphatase (APH) and acid phosphatase (ACPH) loci. The two populations differed consistently in allele frequencies at both loci. The APH locus is on the inversion-free X chromosome; the chromosomal locus of the autosomal ACPH is unknown, and could involve inversion polymorphism. Wild females from Missouri and Louisiana populations heterozygous at the APH locus carried more sperm at capture than did the corresponding homozygotes. This heterotic association was significant for the combined samples, and whether it was the result of heterosis at the enzyme locus studied, or due to geographically widespread close linkage with other heterotic loci, it should help to maintain heterozygosity at the APH locus. In a Louisiana collection which included large numbers of sperm-free females, simultaneous homozygosity at both enzyme loci was significantly associated with lack of sperm. It is suggested that the latter association is the result of young heterozygous females achieving sexual maturity earlier than do the double homozygotes. The average effective sperm load for 225 wild females was only 29.4, suggesting the necessity for frequent repeat-mating in nature to maintain female fertility. A comparison of the sex-linked APH genotypes of wild females with those of their daughters indicated that among 295 wild-inseminated females from five populations, 35% had mated more than once, and of this 35%, six females had mated at least three times. Because of ascertainment difficulties, it is clear that the true frequency of multiple-mating in nature must have been much higher than the observed 35%. Laboratory studies indicate that multiple-mating in this species does not involve sperm displacement, possibly due to the small number of sperms transmitted per mating, and the fact that the sperm receptacles are only partially filled by a given mating. (+info)
Health status of Persian Gulf War veterans: self-reported symptoms, environmental exposures and the effect of stress.
BACKGROUND: Most US troops returned home from the Persian Gulf War (PGW) by Spring 1991 and many began reporting increased health symptoms and medical problems soon after. This investigation examines the relationships between several Gulf-service environmental exposures and health symptom reporting, and the role of traumatic psychological stress on the exposure-health symptom relationships. METHODS: Stratified, random samples of two cohorts of PGW veterans, from the New England area (n = 220) and from the New Orleans area (n = 71), were selected from larger cohorts being followed longitudinally since arrival home from the Gulf. A group of PGW-era veterans deployed to Germany (n = 50) served as a comparison group. The study protocol included questionnaires, a neuropsychological test battery, an environmental interview, and psychological diagnostic interviews. This report focuses on self-reported health symptoms and exposures of participants who completed a 52-item health symptom checklist and a checklist of environmental exposures. RESULTS: The prevalence of reported symptoms was greater in both Persian Gulf-deployed cohorts compared to the Germany cohort. Analyses of the body-system symptom scores (BSS), weighted to account for sampling design, and adjusted by age, sex, and education, indicated that Persian Gulf-deployed veterans were more likely to report neurological, pulmonary, gastrointestinal, cardiac, dermatological, musculoskeletal, psychological and neuropsychological system symptoms than Germany veterans. Using a priori hypotheses about the toxicant effects of exposure to specific toxicants, the relationships between self-reported exposures and body-system symptom groupings were examined through multiple regression analyses, controlling for war-zone exposure and post-traumatic stress disorder (PTSD). Self-reported exposures to pesticides, debris from Scuds, chemical and biological warfare (CBW) agents, and smoke from tent heaters each were significantly related to increased reporting of specific predicted BSS groupings. CONCLUSIONS: Veterans deployed to the Persian Gulf have higher self-reported prevalence of health symptoms compared to PGW veterans who were deployed only as far as Germany. Several Gulf-service environmental exposures are associated with increased health symptom reporting involving predicted body-systems, after adjusting for war-zone stressor exposures and PTSD. (+info)
Home healthcare orders: an assessment of service satisfaction by internists, surgeons, and medical subspecialists.
We conducted a pilot study to evaluate the satisfaction of general internists, medical subspecialists, and surgeons with the quality of home health orders generated by home health agencies. Using a mail survey, we polled 69 physician specialists at Tulane University Medical Center. The percentage of physicians satisfied with the appropriateness of services for the level and type of care, consistency of medication with that prescribed, sufficiency of data on the certification form to assess service continuation, timeliness of orders, and overall health service delivery was 94%, 92%, 69%, 52%, and 88%, respectively. Compared with medical subspecialists and surgeons, general internists were more likely to report that the data on the form were sufficient. Physicians who were satisfied with at least one of the four measures of quality for home health orders were more likely to be satisfied with the overall delivery of services by home health agencies. Our results demonstrate, for the first time, that physicians overall are satisfied with home healthcare orders. However, level of satisfaction with orders is related to the physician's specialty. Areas that physicians were less satisfied with included timeliness of orders and sufficiency of data on the form to assess service continuation. Further studies using a larger population and more specific indicators of healthcare orders quality are recommended. (+info)
The validity and usage of resource utilization data among a group of primary care physicians.
The use of individual resource utilization scores to compare primary care physicians (PCPs) has become more commonplace as managed care organizations (MCOs) increase their penetration into the US healthcare market. This study looks at the validity and usage of these scores among a group of PCPs within a multispecialty clinic that is part of an integrated managed care network. Personal interviews were conducted with PCPs; and reviews were done of the practice site paper charts, the computerized visit record system of the clinic and affiliated hospital, and the MCO-supplied resource utilization data on the 25 patients of each PCP on whom the most healthcare dollars were spent in 1995. As of October 1996, few PCPs had done more than a cursory review of their resource utilization data. None had identified the patients who use the most resources or developed any methods to proactively manage those patients with a history of high utilization. The clinic's communication systems alerted the PCPs less than 50% of the time when patients for whom they were responsible had high utilization of services. Patients appeared to be assigned to the incorrect PCP more than 20% of the time. All players in this managed care network--PCPs, clinic administration, and the MCO--must work together to improve the current system before resource utilization data are considered valid and are incorporated more fully into clinical practice. (+info)
Cost as a barrier to condom use: the evidence for condom subsidies in the United States.
OBJECTIVES: This study sought to determine the impact of price on condom use. METHODS: A program based on distribution of condoms at no charge was replaced with one providing low-cost condoms (25 cents). Pretest and posttest surveys asked about condom use among persons reporting 2 or more sex partners. RESULTS: At pretest, 57% of respondents had obtained free condoms, and 77% had used a condom during their most recent sexual encounter. When the price was raised to 25 cents, the respective percentages decreased to 30% and 64%. CONCLUSIONS: Cost is a barrier to condom use. Free condoms should be distributed to encourage their use by persons at risk for HIV and other sexually transmitted diseases. (+info)
Plasma homocysteine distribution and its association with parental history of coronary artery disease in black and white children: the Bogalusa Heart Study.
BACKGROUND: Elevated homocysteine is associated with increased risk for coronary artery disease (CAD) in adults, but its distribution in children is not well documented. We examined the distribution of homocysteine in children and its relation to parental history of CAD. METHODS AND RESULTS: A subsample of 1137 children (53% white, 47% black) aged 5 to 17 years in 1992 to 1994 examined in the Bogalusa Heart Study (n=3135), including all with a positive parental history of CAD (n=154), had plasma homocysteine levels measured. Homocysteine correlated positively with age (r=0.16, P=0.001). No race or sex differences in homocysteine levels were observed; geometric mean (GM) levels were 5.8 micromol/L (95% CI, 5.6 to 6.1) among white males, 5.8 micromol/L (95% CI, 5.5 to 6.0) among white females, 5.6 micromol/L (95% CI, 5.4 to 5.8) among black males, and 5.6 micromol/L (95% CI, 5.4 to 5.9) among black females. Children with a positive parental history of CAD had a significantly greater age-adjusted GM homocysteine level (GM, 6.7 micromol/L; 95% CI, 6.4 to 7.1) than those without a positive history (GM, 5.6 micromol/L; 95% CI, 5.4 to 5.7); this relation was observed in each race-sex group. CONCLUSIONS: Higher homocysteine levels were observed among children with a positive family history of CAD. Additional studies should elucidate the contribution of genetic, dietary, and other factors to homocysteine levels in children. (+info)
Aldicarb as a cause of food poisoning--Louisiana, 1998.
Cholinesterase-inhibiting pesticides (i.e., organic phosphates and carbamates), widely used in agriculture, can cause illness if they contaminate food or drinking water. Aldicarb, a regulated carbamate pesticide, is highly toxic, and the U.S. Environmental Protection Agency (EPA) requires applicators to be trained and certified. This report describes a foodborne outbreak of aldicarb poisoning that occurred when improperly stored and labeled aldicarb was used mistakenly in food preparation. (+info)
Molecular characterization of Haemophilus ducreyi strains from Jackson, Mississippi, and New Orleans, Louisiana.
Chancroid, a sexually transmitted disease caused by Haemophilus ducreyi, is one of the most common genital ulcer diseases in developing countries. In the United States, while less common, the disease has been associated with outbreaks in inner cities, particularly among persons who engage in sex for drugs or money. Two outbreaks of chancroid were recently studied in the United States, one in New Orleans (from 1990 to 1992) and one in Jackson, Mississippi (from 1994 to 1995). By use of ribotyping, plasmid content, and antibiotic susceptibility, the chancroid cases in New Orleans were found to be due to a limited number of strains, consistent with a limited introduction of H. ducreyi into this community. The H. ducreyi isolates from New Orleans and Jackson had different ribotype patterns, suggesting that the two outbreaks were probably not linked. (+info)