Analysis of the Drosophila female sterile mutation fs(1) 1304 by pole cell transplantation experiments

The Drosophila melanogaster mutant fs(1)1304 is an ovary autonomous female sterile mutant that causes abnormal morphology of the egg. Vitellogenesis proceeds at an abnormally slow rate in homozygous females. We have used pole cell transplantation to construct germ line mosaics in order to determine whether the 1304 defect depends upon the genotype of the germ line cells (oocyte or nurse cells) or the somatic line (follicle cells). We have found that the germ line is the primary target tissue where the mutant gene is expressed.     

Ovarian defects in hybrids of the species pair Drosophila virilis and Drosophila texana

In interspecific matings between Drosophila virilis and Drosophila texana female sterility is observed in F₂ hybrid females. A previous study has shown that no vitellogenin synthesis occurs in the fat body of sterile hybrid females. The results presented in this paper show that hybrid ovaries of sterile females transplanted into the abdomens of females of the parental species are not able to develop upon maturity. With few exceptions, the hybrid ovaries remained alive in the host environment, but their oocytes failed to develop to vitellogenic stages. Thus, in hybrid females between Drosophila virilis and Drosophila texana sterility is the result of defects in both the two main developmental processes of egg maturation, the synthesis of vitellogenins in the fat body and the uptake of vitellogenins by the ovary. Dev Genet 20:47–52, 1997. © 1997 Wiley-Liss, Inc.     

Association between obesity and patient satisfaction

Objective: To examine the relationship between BMI and patient satisfaction with health care providers using a nationally representative survey. Research Methods and Procedures: This analysis examined the 9914 adult patients who completed the 2000 Medical Expenditure Panel Survey and had visited a health care provider within 12 months of the survey. Linear regression models were employed with patient satisfaction as the dependent variable. The patient satisfaction scale was based on ratings from five questions assessing the quality of provider interactions. The independent variable was BMI, with adjustments for the domains of demographics, social‐economic status, health attitudes and behavior, health status, and health care use. BMI (weight in kilograms/square of height in meters) was classified as normal weight (18.5 to 24.9), overweight (25.0 to 29.9), or obese (≥30.0). Hierarchical models were used to evaluate how each domain modified the BMI‐satisfaction association. Results: Obese patients reported significantly greater satisfaction with their health care providers than their normal‐weight counterparts did (p < 0.05). There were no significant differences in satisfaction between normal‐weight and overweight patients or between overweight and obese patients. The health status domain produced the largest modification in the BMI‐satisfaction relationship. Examination of interaction effects revealed that the association between BMI and satisfaction was confined to older persons. Discussion: In this nationally representative sample of individuals, obese persons were more satisfied than their normal‐weight counterparts. This finding counters those of previous studies. Incomplete adjustments for health care use and insurance status may have led to those conclusions.     

Evidence for association of endothelial cell nitric oxide synthase gene polymorphism with earlier progression to end-stage renal disease in a cohort of Hellens from Greece and Cyprus

Nitric oxide (NO) is thought to be an important factor in the deterioration of renal function. A variable-number tandem 27-bp repeat in intron 4 of the endothelial cell nitric oxide synthase (NOS3) gene has been found to be associated with the plasma levels of NO metabolites. Two alleles are of varied frequencies in different populations (a and b). The shorter allele a has been associated in Japanese populations with the progression of renal disease. Here we investigated this hypothesis by studying the putative role of this polymorphism in a Hellenic population of patients with end-stage renal disease (ESRD). We analyzed the genotypes of 361 ESRD patients and 295 healthy Hellens from Greece and Cyprus. The frequencies of NOS3-4bb, NOS3-4ab, and NOS3-4aa were 0.69, 0.27, and 0.03, respectively, in the control group and 0.71, 0.24, and 0.04 in the group of patients. The data in the two populations were analyzed by the chi-square and Fisher's exact tests. The frequencies of these three genotypes of NOS3-4 polymorphism in the Hellenic population of Greece and Cyprus are similar to those observed in other Caucasian populations. Moreover, our results from three patient groups, autosomal dominant polycystic kidney disease (ADPKD), diabetes mellitus (DM), and non-DM, showed that the frequencies of aa and ab genotypes in the patient populations were not significantly different from those observed in the control group. This work indicates that NOS3-4 polymorphism does not show any association with the development of ESRD in this studied European population. However, examination of the data regarding progression to ESRD within 5 years or after more than 5 years following clinical diagnosis of ADPKD provided evidence of statistical difference (p = 0.048, before Bonferroni correction), with faster progression in the group of ADPKD patients who carried allele a.     

Biochemical and immunocytochemical analysis of vitellogenesis in the olive fruit fly Dacus (bactrocera) oleae (Diptera: Tephritidae)

Synthesis and selective accumulation of the major yolk proteins in the developing oocytes of the species Dacus oleae (Diptera: Tephritidae) was studied biochemically and by immunoelectron microscopy. In the hemolymph of adult females, two yolk proteins precursors (or vitellogenins) have been detected. They each exhibit a similar molecular weight and isoelectric point to their respective mature yolk proteins (or vitellins), while electrophoretic analysis of their synthetic profile shows that their levels in the hemolymph increase rapidly during development. Immunogold electron microscopy of ovarian sections, revealed that the hemolymph vitellogenins reach the oocyte through enlarged inter-follicular spaces and demonstrated vitellogenin synthesis by the follicle cells of the vitellogenic follicles. The newly synthesized vitellogenins follow a distinct secretory pathway into these cells as compared to other components being synthesized at the same time (e.g. the vitelline envelope proteins), since they were found in secretory vesicles that appeared to be differentiated from those destined to participate in the vitelline envelope. The vitellogenin-containing vesicles exocytose their contents directionally into the follicle cell/vitelline envelope boundary, and subsequently the vitellogenins diffuse among the gaps of the forming vitelline envelope and reach the oocyte plasma membrane. Their internalization by the oocyte includes the formation of an endocytic complex consisting of coated pits, coated vesicles, endosomes, transitional yolk bodies, and finally mature yolk bodies, in which the storage of the vitellins and other yolk proteins occur. These results are discussed in relation to data obtained from other Dipteran species.     

On the association between daily mortality and air mass types in Athens,Greece during winter and summer

In this study, we examined the short-term effects of air mass types on mortality in Athens, Greece. An objective air mass types classification was used, based on meteorological parameters measured at the surface. Mortality data were treated with generalized additive models (GAM) and extending Poisson regression, using a LOESS smoother to control for the confounding effects of seasonal patterns, adjusting also for temperature, long-term trends, day of the week, and ambient particle concentrations. The introduced air mass classification explains the daily variation of mortality to a statistically significant degree. The highest daily mortality was observed on days characterized by southerly flow conditions for both the cold (increase in relative risk for mortality 9%; with a 95% confidence interval: 3-14%), and the warm period (7%; with a 95% confidence interval: 2-13%) of the year. The northeasterly flow is associated with the lowest mortality. Effects on mortality, independent of temperature, are observed mainly for lag 0 during the cold period, but persist longer during the warm period. Not adjusting for temperature and/or ambient particle levels slightly alters the results, which then reflect the known temperature and particle effects, already reported in the literature. In conclusion, we find that air mass types have independent effects on mortality for both the cold and warm season and may be used to predict weather-related adverse health effects.     

Expression of growth hormone-releasing hormone (GHRH) and splice variant of GHRH receptors in normal mouse tissues

Growth hormone-releasing hormone (GHRH) stimulates the production and release of growth hormone in the pituitary and induces cell proliferation in a variety of peripheral tissues and tumors. These extrapituitary effects of GHRH are in many cases mediated by a splice variant of GHRH receptor designated SV1 that differs from the pituitary GHRH receptor in a small portion of its amino-terminal region. While SV1 has been detected in several primary tumors and many cancer cell lines its expression in normal tissues remains unclear. In this study we report the results of an immunohistochemical analysis for SV1 and GHRH expression in normal mouse tissues. For the detection of SV1 immunoreactivity we used a polyclonal antiserum against segments 1-25 of the SV1 receptor protein. Mouse heart, colon, lungs, small intestine, stomach and kidneys exhibited increased SV1 immunoreactivity. These tissues were also positive for GHRH expression, however, tissues such as the endometrium were positive only for GHRH and not for SV1 expression. On the contrary, testis were positive for SV1 and not for GHRH expression. These results indicate that SV1 may play a role in normal physiology.     

Cholesteryl ester-transfer protein (CETP) polymorphism and the association of acute coronary syndromes by obesity status in Greek subjects: the CARDIO2000-GENE study

OBJECTIVE: Cholesterol ester transfer protein (CETP) regulates plasma lipid distribution. The present study aimed to investigate whether the CETP gene (Taq1B) polymorphism predisposes to Acute Coronary Syndromes (ACS) depending on obesity status. METHODS: We studied demographic, lifestyle and clinical information in 237 hospitalized patients (185 males) with a first event of an ACS and 237 controls matched by age and sex. CETP Taq1B genotyping was performed by PCR-RFLP analysis. RESULTS: Overall, the CETP genotype frequencies were, in patients: 14% (n = 33), 35% (n = 83) and 51% (n = 121) and in controls: 17% (n = 39), 33% (n = 78) and 50% (n = 120) for B2B2, B1B1 and B1B2 respectively (p = 0.72). A significant interaction (p for interaction <0.001) was observed between obesity status and CETP concerning the likelihood of having ACS. Therefore, we stratified our analysis by obesity status and observed that B2B2 was associated with a 0.27 times lower likelihood of having ACS among normal-weight people (OR = 0.27, p = 0.02). No significant relationships were observed among overweight or obese participants. CONCLUSIONS: These findings provide evidence of a protective effect of the B2B2 genotype of the CETP Taq1B polymorphism on the likelihood of having a first event of ACS in normal-weight persons.     

Obesity and the Use of Health Care Services

Objective: This study investigated differences in the use of health care services and associated costs between obese and nonobese patients. Research Methods and Procedures: New adult patients (N = 509) were randomly assigned to primary care physicians at a university medical center. Their use of medical services and related charges was monitored for 1 year. Data collected included sociodemographics, self‐reported health status using the Medical Outcomes Study Short Form‐36, evaluation for depression using the Beck Depression Index, and measured height and weight to calculate BMI. Results: Obese patients included a significantly higher percentage of women and had higher mean age, lower mean education, lower mean health status, and higher mean Beck Depression Index scores. Obese patients had a significantly higher mean number of visits to both primary care (p = 0.0005) and specialty care clinics (p = 0.0006), and a higher mean number of diagnostic services (p < 0.0001). Obese patients also had significantly higher primary care (p = 0.0058), specialty clinic (p = 0.0062), emergency department (p = 0.0484), hospitalization (p = 0.0485), diagnostic services (p = 0.0021), and total charges (p = 0.0033). Controlling for health status, depression, age, education, income, and sex, obesity was significantly related to the use of primary care (p = 0.0364) and diagnostic services (p = 0.0075). There was no statistically significant relationship between obesity and medical expenditures in any of the five categories or for total charges. Discussion: Obesity is a chronic condition requiring long‐term management, with an emphasis on prevention. If this critical health issue is not appropriately addressed, the prevalence of obesity and obesity‐related diseases will continue to grow, resulting in escalating use of health care services.