Lung surfactant-associated glycoproteins and proteolipids in human amniotic fluids evaluated by dot immunobinding assays

Dot immunobinding assays for the quantitation of two classes of proteins associated with lung surfactant phospholipids in human amniotic fluid are described. With the use of these assays it was determined that the two classes of surfactant proteins accumulate in the amniotic fluid at the same rate. The concentrations of disaturated phosphatidylcholine and the surfactant-associated proteins are less closely correlated. Centrifugation of amniotic fluids either before or after freezing resulted in a loss ranging from 10 to 35 percent of both surfactant disaturated phosphatidylcholine and proteins depending on the relative centrifugal force used. Preterm amniotic fluids contained significantly less of both surfactant-associated proteins, as well as disaturated phosphatidylcholine, than did term amniotic fluids which suggests that the use of these specific protein markers may enhance the assessment of fetal lung maturity.     

Reduced cell proliferation in fetal lung after maternal administration of pilocarpine. A scintillation autoradiographic study

Fetuses were obtained on the 28th gestational day from pregnant New Zealand white rabbits treated daily, on the 24th through the 27th gestational day, with pilocarpine HCl, 5 mg/kg in saline, or saline alone. Lung fragments from these fetuses were incubated for two hours in medium containing ³H-thymidine. Scintillation autoradiography of 1-μm-thick sections of these fetal lungs revealed that the lung tissue from pilocarpine-treated fetuses had significantly lower labelled cell indices for both alveolar epithelial cells and interstitial cells. These results indicate that pilocarpine treatment promotes differentiation of immature cells in the fetal lung at the expense of cell proliferation.     

Cost comparison of genetic and clinical screening in families with hereditary hemorrhagic telangiectasia

Endoglin (ENG) and ALK-1 mutations cause hereditary hemorrhagic telangiecstasia (HHT), an autosomal dominant disorder leading to vascular dysplasia in the form of mucocutaneous telangiectasia and visceral arteriovenous malformations (AVMs). We proposed to compare two alternative strategies for management of HHT: screening HHT families with molecular diagnostic tests followed by targeted clinical screening versus conventional clinical screening. A decision analytic model was constructed to compare screening strategies for a hypothetical HHT family. The family consists of 1 index case and 13 relatives. The clinical screening protocol in use at the Canadian HHT Center in Toronto was assumed to be the standard of care. Unit costs for clinical screening (in Canadian dollars) were obtained from the 2003 Ontario Health Insurance Schedule of Benefits. Genetic screening costs were estimated for quantitative multiplex PCR and sequencing of Endoglin (ENG) and ALK-1 genes, as performed at HHT Solutions, Toronto. The genetic screening strategy resulted in a net cost of $4,060 per individual versus $5,975 for the clinical screening strategy. The genetic screening strategy would save $1,915 per family member or $26,810 saved per family. Sensitivity analyses revealed that the genetic screening strategy was cost saving over all plausible ranges of input variables for all hypothetical families tested. We concluded that a genetic screening strategy with targeted clinical screening is more economically attractive than conventional clinical screening and results in a reduction in the number of clinical tests for family members who do not have HHT.     

Iron and fur regulation in Vibrio cholerae and the role of fur in virulence

Regulation of iron uptake and utilization is critical for bacterial growth and for prevention of iron toxicity. In many bacterial species, this regulation depends on the iron-responsive master regulator Fur. In this study we report the effects of iron and Fur on gene expression in Vibrio cholerae. We show that Fur has both positive and negative regulatory functions, and we demonstrate Fur-independent regulation of gene expression by iron. Nearly all of the known iron acquisition genes were repressed by Fur under iron-replete conditions. In addition, genes for two newly identified iron transport systems, Feo and Fbp, were found to be negatively regulated by iron and Fur. Other genes identified in this study as being induced in low iron and in the fur mutant include those encoding superoxide dismutase (sodA), fumarate dehydratase (fumC), bacterioferritin (bfr), bacterioferritin-associated ferredoxin (bfd), and multiple genes of unknown function. Several genes encoding iron-containing proteins were repressed in low iron and in the fur mutant, possibly reflecting the need to reserve available iron for the most critical functions. Also repressed in the fur mutant, but independently of iron, were genes located in the V. cholerae pathogenicity island, encoding the toxin-coregulated pilus (TCP), and genes within the V. cholerae mega-integron. The fur mutant exhibited very weak autoagglutination, indicating a possible defect in expression or assembly of the TCP, a major virulence factor of V. cholerae. Consistent with this observation, the fur mutant competed poorly with its wild-type parental strain for colonization of the infant mouse gut.     

Effects of a yearlong moderate-intensity exercise and a stretching intervention on sleep quality in postmenopausal women

STUDY OBJECTIVES: To examine the effects of a moderate-intensity exercise or stretching intervention and changes in fitness, body mass index, or time spent outdoors on self-reported sleep quality and to examine the relationship between the amount and timing of exercise and sleep quality. DESIGN: A randomized intervention trial. SETTING: A cancer research center in Seattle, Washington. PARTICIPANTS: Postmenopausal, overweight or obese, sedentary women not taking hormone replacement therapy, aged 50 to 75 years, and recruited from the Seattle metropolitan area. INTERVENTIONS: A yearlong moderate-intensity exercise (n=87) and a low-intensity stretching (n=86) program. MEASUREMENTS AND RESULTS: Among morning exercisers, those who exercised at least 225 minutes per week had less trouble falling asleep (odds ratio [OR]: 0.3, P < or = .05) compared with those who exercised less than 180 minutes per week. However, among evening exercisers, those who exercised at least 225 minutes per week had more trouble falling asleep (OR: 3.3, P < or = .05) compared to those who exercised less than 180 minutes per week. Stretchers were less likely to use sleep medication (OR = 0.4, P < or = .05) and have trouble falling asleep (OR: 0.7, P < or = .10) during the intervention period compared with baseline. A greater than 10% versus a 1% or less increase in maximum O2 consumption over the year was associated with longer sleep duration (P < or = .05), less frequently falling asleep during quiet activities (P < or = .05), and less use of sleep medication (P < or = .05). Reductions in body mass index and increases in time spent outdoors had inconsistent effects on sleep quality. CONCLUSIONS: Both stretching and exercise interventions may improve sleep quality in sedentary, overweight, postmenopausal women. Increased fitness was associated with improvements in sleep. However, the effect of moderate-intensity exercise may depend on the amount of exercise and time of day it is performed.     

Monte Carlo calculation of the sensitivity of a commercial dose calibrator to gamma and beta radiation

The detection process used in a commercial dose calibrator was modeled using the GEANT 3 Monte Carlo code. Dose calibrator efficiency for gamma and beta emitters, and the response to monoenergetic photons and electrons was calculated. The model shows that beta emitters below 2.5 MeV deposit energy indirectly in the detector through bremsstrahlung produced in the chamber wall or in the source itself. Higher energy beta emitters (E > 2.5 MeV) deposit energy directly in the chamber sensitive volume, and dose calibrator sensitivity increases abruptly for these radionuclides. The Monte Carlo calculations were compared with gamma and beta emitter measurements. The calculations show that the variation in dose calibrator efficiency with measuring conditions (source volume, container diameter, container wall thickness and material, position of the source within the calibrator) is relatively small and can be considered insignificant for routine measurement applications. However, dose calibrator efficiency depends strongly on the inner-wall thickness of the detector.     

Small for gestational age associated with short stature during adolescence

This study examined the relationship between intrauterine growth retardation and adolescent stature in a sample of 1510 White subjects (754 males and 756 females) who were evaluated at birth and at the ages of 15, 16, and 17 years. The subjects were classified into two groups based on birthweight, small for gestational age (SGA) and appropriate for gestational age (AGA), corresponding respectively to values below the 10th, and between the 11th and 99th, percentiles of gestational age and sex. Results showed that boys and girls born prematurely (gestational age < 37 weeks of gestation) attained the same stature as those born at full term (>37 weeks of gestation). In contrast, those born SGA were significantly shorter than their counterparts born AGA. The average reduction in stature was 4.9 cm for males and 2.9 cm for females. When the analysis included adjustments for parental stature (and adolescent's age at menarche for females), the average reduction in stature equaled about 3.5 cm for males and 2.0 cm for females. It is thus concluded that the stature deficit reflects a reduction in growth rate rather than delay in maturation. © 1994 Wiley-Liss, Inc.     

Effects of COVID-19 on University Student Food Security

During COVID-19 restrictions in spring 2020, college students experienced closed dormitories and increased unemployment and many students moved in with their families. College students were vulnerable to food insecurity pre-pandemic and this study examined how the living situations and food security status changed for Midwestern university students due to COVID-19 restrictions. An email survey administered to Iowa State University students between the ages of 18 and 30 who physically attended campus prior to its closure produced 1434 responses. Students living with a parent or guardian increased by 44% and were less likely to experience food insecurity or less likely to work. They had lower stress and ate more home-cooked meals. Students living on their own had higher rates of food insecurity, greater stress, poorer health status, higher cooking self-efficacy, and worked more hours. Seventeen percent of all students were food insecure; related factors were non-White ethnicity, lower cooking self-efficacy, undergraduate status, receipt of financial aid, employment, stress, living in the same situation as before the campus closure, and consumption of more take-out or fast food. These individuals had more barriers to food access. Knowledge of these factors provide useful information to inform future support services for this population in similar conditions.     

Rift Valley Fever and Crimean-Congo Hemorrhagic Fever Viruses in Ruminants,Jordan

The epidemiology of Rift Valley fever virus (RVFV) and Crimean-Congo hemorrhagic fever virus (CCHFV) in Jordan is unknown. Our investigation showed 3% of 989 tested dairy cattle, sheep, and goats were RVFV seropositive and 14% were CCHFV seropositive. Ongoing surveillance is needed to assess risk to humans and protect public health.