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981.
Growth hormone (GH) deficiency is a significant clinical problem, since growth hormone is essential for the regulation of growth, metabolism, and the cardiovascular system. Stem and progenitor cells have been identified in many adult tissues. Recently, our laboratory identified a cell type within the adult pituitary gland with stem cell-like properties, which we have termed pituitary colony-forming cells (PCFCs). Herein we investigate the ability of PCFCs to survive and differentiate in vivo. Enriched populations of PCFCs were transplanted into an in vivo microchamber model. Grafts were harvested at 6 weeks post-transplant and tested for surviving donor cells (LacZ(+)) or for differentiation (GH(+)). The results showed that donor cells survived in chambers (LacZ(+)) and underwent division (phosphohistone-H3-positive). Furthermore, grafted cells showed colocalization of LacZ and GH, suggesting differentiation. To confirm differentiation, donor cells were obtained from a GH-enhanced green fluorescent protein (eGFP) reporter transgenic mouse model that expressed eGFP under control of the GH promoter. Cells that were eGFP(-), that is, GH(-), were selected by fluorescence-activated cell sorting (FACS) and transplanted. After 6 weeks, eGFP(+)GH(+) cells were detected in grafts by immunostaining and by FACS analysis of digested grafts. In conclusion, PCFCs have the capacity to divide and differentiate into GH(+) cells in vivo. The vascularized tissue chamber model is an ideal model to investigate the environmental niche for PCFC expansion and differentiation and has the potential to be developed into a growth hormone-releasing organoid in vivo. Disclosure of potential conflicts of interest is found at the end of this article.  相似文献   
982.
OBJECTIVE: The Hilo Women's Health Survey was designed and administered to gather baseline data on women's health in Hilo, HI. This randomized, cross-sectional study allowed for a focus on ethnic differences in symptom reporting. The results presented here focus on hot flash and night sweat experience among Japanese-American and European-American women. DESIGN: Survey packets were mailed to street addresses associated with parcel numbers pulled randomly from Hilo tax maps. Of the 6,401 survey packets delivered to households, 1,824 questionnaires were completed and returned. The results reported here are based on 869 women aged 40 to 60, of whom 249 described themselves to be 100% Japanese and 203 described themselves to be 100% European-American. Logistic regression analyses were used to examine whether the relationship between ethnicity and vasomotor symptoms persisted after controlling for other variables. RESULTS: European-American participants were more likely to have ever experienced a hot flash as compared with Japanese-American participants (72% vs 53%, P<0.01). During the 2 weeks before the survey, European-American participants were more likely to have experienced hot flashes (P<0.05) and night sweats (P<0.01). In logistic regression analyses, after controlling for age, body mass index, menopause status, level of education, financial comfort, smoking habits, alcohol intake, exercise, use of hormone therapy, and soy intake, European-American women were still significantly more likely to have experienced hot flashes (odds ratio=1.858) and night sweats (odds ratio=2.672). CONCLUSIONS: The results, based on self-reporting of menopausal symptoms, indicate that Japanese-American women report fewer hot flashes and night sweats than European-American women. Japanese-American women reported a higher intake of soy, but soy intake was not associated with fewer vasomotor symptoms.  相似文献   
983.
The epidemiology of multiple sclerosis suggests that a complex interaction of genes and environment contribute to susceptibility. To enrich for families with large genetic effects and to potentially reduce genetic heterogeneity, we screened a sample of 18,794 probands and identified forty families with four or more affected individuals. Within these 40 families, HLA DRB1*15 was present in 70% of affected individuals; the transmission disequilibrium test showed a significant excess in transmission of DRB1*15 alleles to affected individuals (47 transmitted, 19 untransmitted, χ 2 = 11.9, p = 0.00057). A 10 cM genome scan was performed and analyzed for linkage under a parametric model with heterogeneity. No excess of significant sharing was observed (HLOD > 3.3) in the parametric multipoint analysis. No region exceeded that for marker GATA8A05 with an HLOD = 1.11. Follow-up genotyping with 17 microsatellites revealed a significant two-point parametric HLOD = 3.99 at marker D4S1597. Transmission disequilibrium tests for markers in this candidate region showed no transmission distortion. A scan for variants in a gene adjacent to D4S1597, PALLD, was negative for synonymous or nonsynonymous changes. A final multipoint scan incorporating all microsatellites in the region provided an HLOD = 1.30. The inability to find significant linkage in these highly penetrant families suggests that linkage is not the optimal tool for dissecting the inheritance of MS.  相似文献   
984.
985.
986.
In this article we examine factors associated with women's self-reports of reproductive ill health symptoms and factors associated with seeking and receiving treatment for the symptoms. We focus on indicators of women's societal position, especially empowerment (indicated by experience of and attitudes toward violence against women), autonomy, and education. We used data from the National Family Health Survey-2 from Kerala state in Southern India. Based on our results we suggest that violence against women, whether actually experienced or internalized as acceptance of its justification, is associated with increased ill health symptoms, and the acceptance of violence is associated with decreased chance of treatment. Women's higher formal education appeared to reduce treatment seeking for reproductive ill health, perhaps due to the stigma associated with sexually transmitted disease (STD) in this cultural setting. Women's work participation had no significant impact, nor did indicators of women's economic and personal autonomy.  相似文献   
987.
Linkage analyses of complex, multifactorial traits and diseases, such as essential hypertension, have been difficult to interpret and reconcile. Many published studies provide evidence suggesting that different genes and genomic regions influence hypertension, but knowing which of these studies reflect true positive results is challenging. The reasons for this include the diversity of analytical methods used across these studies, the different samples and sample sizes in each study, and the complicated biological underpinnings of hypertension. We have undertaken a comprehensive linkage analysis of 371 autosomal microsatellite markers genotyped on 4,334 sibling pairs affected with hypertension from five ethnic groups sampled from 13 different field centers associated with the Family Blood Pressure Program (FBPP). We used a single analytical technique known to be robust to interpretive problems associated with a lack of completely informative markers to assess evidence for linkage to hypertension both within and across the ethnic groups and field centers. We find evidence for linkage to a number of genomic regions, with the most compelling evidence from analyses that combine data across field center and ethnic groups (e.g., chromosomes 2 and 9). We also pursued linkage analyses that accommodate locus heterogeneity, which is known to plague the identification of disease susceptibility loci in linkage studies of complex diseases. We find evidence for linkage heterogeneity on chromosomes 2 and 17. Ultimately our results suggest that evidence for linkage heterogeneity can only be detected with large sample sizes, such as the FBPP, which is consistent with theoretical sample size calculations.  相似文献   
988.
Radon is a well-recognized cause of lung cancer, and studies of underground miners have provided invaluable insights on the mechanisms of radon carcinogenesis. Given the dramatic decreases in occupational exposures and the latent interval between the time of exposure and the development of lung cancer, continued follow-up of these cohorts is needed to address uncertainties in risk estimates. Here, we report on the relationship between radon and lung cancer mortality in a cohort of 1,742 Newfoundland fluorspar miners between 1950 and 2001; follow-up has been extended 11 y from previous analyses. The standardized mortality ratio (SMR) was used to compare the mortality experience of the cohort to similarly aged Newfoundland males. Poisson regression methods were used to characterize the radon-lung cancer relationship with respect to: age at first exposure, attained age, time since last exposure, interactions with cigarette smoking, and exposure rate. In total, 191 lung cancers were observed among underground miners (SMR = 3.09; 95% CI = 2.66, 3.56). ERR/WLMs decreased with attained age and time since last exposure. An inverse dose-rate effect was observed, while age at first exposure was not associated with lung cancer risk. An important strength of this study is that the effects of gamma radiation, thoron, and radioactive dust, common exposures in other miner studies, can be ruled out because the source of radon was from water running through the mine. However, the results should be interpreted cautiously due to uncertainties associated with the estimation of radon exposure levels before ventilation was introduced into the mine, and the relatively small number of lung cancer deaths that precluded joint modeling of multiple risk factors.  相似文献   
989.
OBJECTIVE: To determine the degree to which patients and families enrolled with hospice received services across key categories of palliative care, the extent of hospice-level variability in services delivered, and changes over time in services delivered. DATA SOURCE: Nationally representative sample of 9,409 discharged patients from 2,066 hospices in the National Home and Hospice Care Survey. STUDY DESIGN: Observational, cross-sectional study conducted from 1992 to 2000. The primary outcome is the receipt of services across five key categories of palliative care: nursing care, physician care, medication management, psychosocial care, and caregiver support. DATA COLLECTION: Data were obtained via interview with the hospice staff member most familiar with the patient's care, in conjunction with medical record review. PRINCIPLE FINDINGS: In 2000, 22 percent of patients enrolled with hospice received services across five key categories of palliative care. There was marked variation across hospices in service delivery. One-third of hospices provided patients and families services in one or two of the five key categories of palliative care, whereas 14 percent of hospices provided services across five key categories of palliative care. In multivariable analysis, the odds of receiving any additional hospice service was significantly greater in later compared with earlier years (odds ratio=1.10, 95 percent confidence interval 1.01-1.20). Nevertheless, the percentages of patients in 2000 receiving medication management (59 percent), respite care (7 percent), and physician services (30 percent) remained low. CONCLUSIONS: Hospice care for patients and families varies substantially across hospices. Whereas some hospices provide services across the key categories of palliative care, other hospices do not provide this breadth of services. Greater understanding of the causes of variation in service delivery as well as its impact on patient and family outcomes and satisfaction with end-of-life care is a critical subject for future research. Changes in Medicare's reimbursement policies may help hospices increase the range of services provided to patients and families.  相似文献   
990.
STUDY OBJECTIVE: To evaluate self-reported changes in housing quality and health associated with housing-led area regeneration. DESIGN: A prospective study over 1 year using structured interviews with 50 households who moved to new housing and with 50 matched controls who did not move. SETTING AND PARTICIPANTS: Residents of two social rented housing schemes in the West of Scotland. RESULTS: Small but not statistically significant increases in levels of "excellent" or "good" self-reported health status were found in both groups. Both intervention and control groups experienced reductions in problems related to warmth, but no significant change in how they felt about their house. CONCLUSIONS: It is feasible to conduct prospective controlled studies to evaluate the health effects of housing improvement using matched control groups. The absence of marked improvement in health after moving to new housing might be due to the small sample size or to the limited potential to improve health through this intervention alone.  相似文献   
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