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PubMed1999

A case-control study of malignant melanoma in Israeli kibbutzim.

BACKGROUND: Incidence rates for malignant melanoma in Israel are rising steadily, and the kibbutz population is at increased risk for this malignancy. OBJECTIVES: To assess the risk factors for malignant melanoma among kibbutz members compared to matched healthy controls. METHODS: We conducted a case-control study of 168 malignant melanoma patients and 325 healthy controls, matched by age and gender. Data were collected on three categories of risk: demographic, personal (e.g., skin, eye and hair color), and environmental/behavioral (e.g., sun exposure, use of sunscreens). RESULTS: There were no differences between the groups regarding sociodemographic data. Significantly more patients than controls had fair, vulnerable skin (P < 0.001), light eyes (P < 0.05), and fair hair (P < 0.001). There was no difference in family history of malignant melanoma or other cancers. Patients with malignant melanoma had significantly more additional skin lesions (e.g., keratoses) (P < 0.001). More patients than controls recalled having been exposed to the sun for long periods when they were 6-13 years of age. A conditional logistic regression analysis showed that fair hair, fair vulnerable skin, and additional skin lesions were independently associated with malignant melanoma (P < 0.01). CONCLUSIONS: The main target population for interventions to reduce the incidence of malignant melanoma among kibbutz members should be individuals with these risk factors. A history of increased exposure to the sun from age 6 to 13 should also be taken into account as an independent risk factor.

Adult↗
PubMed2004

Management of invasive candidiasis in critically ill patients.

Candida species have become predominant pathogens in critically ill patients. In this population, invasive candidiasis is associated with a poor prognosis but adequate management can limit the attributable mortality. Adequate management, however, is hampered by a problematic diagnosis as the clinical picture of invasive disease is non-specific and blood cultures have a low sensitivity. Moreover, it is often hard to differentiate colonisation from infection and many critically ill patients are heavily colonised with Candida species, especially when receiving broad-spectrum antibacterials. The question of which antifungal agent to choose has become more complex as the development of new drugs raises promising expectations. Until the 1980s therapy for invasive candidiasis was limited to amphotericin B, but with the advent of new antifungal agents, such as azoles and echinocandins, less toxic therapeutic options are possible and doors have opened towards prevention and optimised therapy in the case of documented candidiasis. Through the arrival of these new antifungal agents, a range of therapeutic strategies for the management of invasive candidiasis has been developed: antifungal prophylaxis, pre-emptive therapy, and empirical and definitive antifungal therapy. Each of these strategies has a specific target population, as defined by specific underlying conditions and/or individual risk factors. Antifungal prophylaxis, in order to prevent candidal infection, is based on the type of underlying diseases with a high risk for invasive candidiasis. Individual risk factors are not taken into account. Potential indications are bone marrow transplantation, liver transplantation, recurrent gastrointestinal perforations or leakages, and surgery for acute necrotising pancreatitis. Pre-emptive therapy is also a preventive strategy. It can be recommended on the basis of an individual risk profile including overt candidal colonisation. Empirical therapy is started in patients with a risk profile for invasive candidiasis. It is recommended in the presence of clinical signs of infection, deteriorating clinical parameters, or a clinical picture of infection not responding to antibacterials but in the absence of a clear causative pathogen. Definitive antifungal therapy is defined as therapy in patients with documented invasive infection. The main goal is to maintain a balance between optimal prevention and timely initiation of therapy on one hand, and to minimise selection pressure in order to avoid a shift towards less susceptible Candida species on the other hand.

Antifungal Agents↗
PubMed2001

A review of hepatitis E virus.

Hepatitis E virus (HEV) is a major cause of outbreaks and sporadic cases of viral hepatitis in tropical and subtropical countries but is infrequent in industrialized countries. The virus is transmitted by the fecal-oral route with fecally contaminated drinking water being the usual vehicle. Hepatitis resulting from HEV infection is a moderately severe jaundice that is self-limiting in most patients. Young adults, 15 to 30 years of age, are the main targets of infection, and the overall death rate is 0.5 to 3.0%. However, the death rate during pregnancy approaches 15 to 25%. Death of the mother and fetus, abortion, premature delivery, or death of a live-born baby soon after birth are common complications of hepatitis E infection during pregnancy. Hepatitis E virus is found in both wild and domestic animals; thus, HEV is a zoonotic virus. The viruses isolated from swine in the United States or Taiwan are closely related to human HEV found in those areas. The close genetic relationship of the swine and human virus suggests that swine may be a reservoir of HEV. In areas where swine are raised, swine manure could be a source of HEV contamination of irrigation water or coastal waters with concomitant contamination of produce or shellfish. Increasing globalization of food markets by industrialized countries has the potential of introducing HEV into new areas of the world. The purpose of this review is to cover certain aspects of hepatitis E including the causative agent, the disease, diagnosis, viral detection, viral transmission, epidemiology, populations targeted by HEV, and the role of animals as potential vectors of the virus.

Animals↗
PubMed1997

Who is still uninsured in Minnesota? Lessons from state reform efforts.

OBJECTIVE: To describe Minnesota's health care system reform efforts and their implications for other state and national reform initiatives, document the rate of uninsurance in 1990 and 1995 with special attention to childrens' access to health insurance, and examine the effectiveness of MinnesotaCare, a voluntary state-subsidized health care plan, in serving its target population. DESIGN: Three cross-sectional telephone surveys: 2-stage random samples of Minnesotans of all ages in 1990 and 1995 and a stratified random sample of MinnesotaCare enrollees in 1994. PARTICIPANTS: For the 2 statewide surveys, 10310 respondents participated in 1990 and 11519 in 1995; more detailed information was collected on approximately 1600 respondents in each survey. Eight hundred MinnesotaCare enrollees participated in the third survey conducted in 1994. MAIN OUTCOME MEASURE: Changes in rates of uninsurance. RESULTS: While the rate of uninsurance increased at the national level, the point-in-time Minnesota rate remained stable and low at 6% between 1990 and 1995. The proportion of children uninsured for 12 months or more decreased from 5.2% in 1990 to 3.1% in 1995, while the proportion of uninsured single adults remained stable at approximately 11%. There was no evidence that MinnesotaCare enrollees are gaming the program, or that the program has resulted in significant erosion from the private market. CONCLUSIONS: MinnesotaCare has enabled the state to maintain a low rate of uninsurance and has reduced this rate among its primary target: children. The program has been less effective in enrolling single adults, although it may be too early to witness the effects of recent expansions targeting this group. Minnesota's experience suggests that other state and national reform efforts aimed at reducing uninsurance, particularly among children, are likely to be successful.

Adult↗
PubMed1995

Approaches for exposure characterization and data needs for hazardous waste site assessment.

This article provides an understanding of the approaches for determining exposure and dose to populations in the vicinity of hazardous waste sites. A review of the federal legislation and jurisdiction for assessments is provided, and the approaches of the U.S. Environmental Protection Agency and the Agency for Toxic Substances and Disease Registry are compared. These methods strive to aid in the evaluation of public health impacts of contaminants that were, are, or may be released to the community, and they are concerned with various aspects of the contaminant fate, human contact, and toxic response for chemicals of concern. Such approaches have been designed for generic contamination scenarios, but they aim to be applicable to a wide range of chemicals and sites in the real world. Along with any modeling framework for exposure and dose characterization, detailed information or real data are requisite for the completion of any site-specific assessment. What kinds of data are needed and where they may be found are also discussed. A comprehensive framework for exposure characterization, recently proposed by Georgopoulos and Lioy, is outlined. The framework is one employing the following elements: chemodynamic analyses of sources and receptors; characterization of the target population; toxicokinetic/toxicodynamic analyses; uncertainty/error analyses; and evaluation of the characterization performance.

Environmental Exposure↗
PubMed1998

COOP Charts in French: translation and preliminary data on instrument properties.

This paper describes the procedure used to translate the COOP Charts into French and provides preliminary information on the instrument's acceptability, reliability and validity. The charts were translated in several steps: seven initial translations were combined into a first pilot version, which was then tested for acceptability, clarity and alternative wordings in two convenience samples taken from the general population (n = 53). The modified version was then reviewed by a lay panel and another translator and submitted by mail to 209 congress participants to test several construct validity hypotheses through known-groups comparisons. A panel of public health professionals discussed the content validity of the charts. Finally, test-retest reliability and concurrent validity with SF-36 Health Survey scores were examined among 65 patients with end-stage renal disease. The translation process identified a wide variability in translation options for several items. The acceptability of the charts was excellent. The test-retest correlations ranged from 0.60 to 0.87. Content validity appeared to be appropriate, except for the chart on 'social support', which combines the questions of need and availability of social support. The utility of illustrations was questioned by some respondents: many claimed not to have used the illustrations in selecting their response, while others found them to be not expressive enough. Most preliminary tests of construct validity were consistent with theory. This French translation of the COOP Charts appears to be ready for more extensive testing in the intended target population of ambulatory patients.

Adolescent↗
PubMed2006

Interpreting household survey data intended to measure insecticide-treated bednet coverage: results from two surveys in Eritrea.

BACKGROUND: As efforts are currently underway to roll-out insecticide-treated bednets (ITNs) to populations within malarious areas in Africa, there is an unprecedented need for data to measure the effectiveness of such programmes in terms of population coverage. This paper examines methodological issues to using household surveys to measure core Roll Back Malaria coverage indicators of ITN possession and use. METHODS: ITN coverage estimates within Anseba and Gash Barka Provinces from the 2002 Eritrean Demographic and Health Survey, implemented just prior to a large-scale ITN distribution programme, are compared to estimates from the same area from a sub-national Bednet Survey implemented 18 months later in 2003 after the roll-out of the ITN programme. RESULTS: Measures of bednet possession were dramatically higher in 2003 compared to 2002. In 2003, 82.2% (95% confidence interval (CI) 77.4-87.0) of households in Anseba and Gash Barka possessed at least one ITN. RBM coverage indicators for ITN use were also dramatically higher in 2003 as compared to 2002, with 76.1% (95% CI 69.9-82.2) of children under five years old and 52.4% (95% CI 38.2-66.6) of pregnant women sleeping under ITNs. The ITN distribution programme resulted in a gross increase in ITN use among children and pregnant women of 68.3% and 48% respectively. CONCLUSION: Eritrea has exceeded the Abuja targets of 60% coverage for ITN household possession and use among children under five years old within two malarious provinces. Results point to several important potential sources of bias that must be considered when interpreting data for ITN coverage over time, including: disparate survey universes and target populations that may include non-malarious areas; poor date recall of bednet procurement and treatment; and differences in timing of surveys with respect to malaria season.

Bedding and Linens↗
PubMed2002

Interventions aimed at improving immunization rates.

BACKGROUND: Immunization rates for children and adults are rising, but coverage levels have not reached national goals. As a result of low immunization rates, vaccine-preventable diseases still occur. In an era of increasing complexity of immunization schedules, rising expectations about the performance of primary care, and large demands on primary care physicians, it is important to understand and promote interventions that work in primary care settings to increase immunization coverage. A common theme across immunization programs in all nations involves the challenge of determining the denominator of eligible recipients (e.g., all children who should receive the measles vaccine), and identifying the best strategy to ensure high vaccination rates. Strategies have focused on patient-oriented interventions (e.g., patient reminders), provider interventions, and system interventions. One intervention strategy involves patient reminder/recall systems. OBJECTIVES: Assess the effectiveness of patient reminder/recall systems in improving immunization rates, and compare the effects of various types of reminders in different settings or patient populations. SEARCH STRATEGY: A systematic search was performed using MEDLINE (1966-1998) and 4 other bibliographic databases: EMBASE, PsychINFO, Sociological Abstracts, and CAB Abstracts. Authors also performed a search of EPOC in April 2001 to update the review. Two authors reviewed the lists of titles and abstracts, and used the inclusion criteria to mark potentially relevant articles for full review. The reference lists of all relevant articles and reviews were back searched for additional studies. Publications of abstracts, proceedings from scientific meetings, and files of study collaborators were also searched for references. SELECTION CRITERIA STUDY DESIGN: Randomized controlled trials (RCT), controlled before and after studies (CBA), and interrupted time series (ITS) studies written in English. TYPES OF PARTICIPANTS: Health care personnel who deliver immunizations and children (birth to 18 years) or adults (18 years and up) who receive immunizations in any setting. Types of interventions: Any intervention that falls within the Effective Practice and Organization of Care Group (EPOC) scope and that includes patient reminder and/or recall in at least one arm of the study. Types of outcome measures: Immunization rates, or the proportion of the target population up-to-date on recommended immunizations. Outcomes were acceptable for either individual vaccinations (e.g., influenza vaccination) or standard combinations of recommended vaccinations (e.g., all recommended vaccinations by a specific date or age). DATA COLLECTION AND ANALYSIS DATA COLLECTION: Each study was read independently by two reviewers. Disagreements between reviewers were resolved by a formal reconciliation process to achieve consensus. ANALYSIS: Results are presented for individual studies as relative rates for randomized controlled trials, and as absolute changes in percentage points for controlled before and after studies. Pooled results were presented using the random effects model. MAIN RESULTS: Patient reminder/recall systems were effective in improving immunization rates in 33 of 41 included studies, irrespective of baseline immunization rates, patient ages, type of setting, or type of vaccination. Increases in immunization rates due to reminders were in the range of 5 to 20 percentage points. Reminders were effective for childhood vaccinations (OR=2.02, 95% CI =1.49,2.72), childhood influenza vaccinations (OR=4.19, 95% CI =2.07,8.49), adult pneumococcus or tetanus (OR=5.14, 95%CI = 1.21, 21.8), and adult influenza vaccinations (OR=2.29, 95%CI = 1.69, 3.10). While reminders were most effective in academic settings (OR = 3.33, 95% CI = 1.98, 5.58), they were also highly effective in private practice settings (OR=1.79, 95% CI = 1.45, 2.22) and public health clinics (OR = 2.09, 95% CI = 1.42, 3.07). All types of reminders were effective (postcards, letters, telephone or autodialer calls), with telephone being the most effective but most costly. REVIEWER'S CONCLUSIONS: Patient reminder/recall systems in primary care settings are effective in improving immunization rates.

Humans↗
PubMed2002

The structure of body measurements for the determination of garment system for young Croatian men.

The determination and promotion of garment size systems require a knowledge of the proportions of the human body i.e. of anthropometric measures of a certain population. In order to create and promote a garment size system it is necessary to establish a correct relationship between the body parts or body measures. Possible interregional body differences are often neglected in the process, although they can be considerable even in cases of sex- and age- limited populations. This has been confirmed by an investigation of body measures for determining garment sizes carried out on a randomly selected sample of 4,268 healthy and normally developed men aged 18-22. The investigation was performed in 1993 on five locations each one representing a definite region of the Republic of Croatia: Jastrebarsko (central), Koprivnica (northwest), Pula (southwest), Sinj (south) and Pozega (northeast). The survey instruments were 50 body measures chosen according to ISO standards for garment sizes. Interregional differences were considerable in all body measures. The role of those measures and their contribution to the differences was confirmed by discriminative analysis with regions as a priori defined samples. Besides the differences in body size, significant differences in body build were established, mostly in the northeast region of Croatia and partly also in the northwest region. It is the difference in body build (besides the high number of necessary measurements) that makes the determination of garment size systems so complex. In order to establish an appropriate and purposeful garment size standard it is necessary to collect more information and also introduce the entity of target-population into previously determined categories in terms of chest circumference and body height.

Adult↗
PubMed1995

The potential benefits and harms of screening for colorectal cancer.

Australian guidelines for colorectal cancer screening for average-risk populations vary from recommendations for annual screening by faecal occult blood testing for those over 40 years to recommendations that screening may be appropriate if requested by an informed patient aged 50 to 75 years. There are five large screening trials, of which three have published mortality data. A meta-analysis of the mortality data suggests a 19 per cent reduction in colorectal cancer mortality (95 per cent confidence intervals 0.68 to 0.96) with Hemoccult screening. Because of the width of the confidence interval, decisions about the magnitude of the effect of screening should await further trial results, which should be available in the next few years. In the interim, we should examine issues of harm and costs in Australia. For example, in the major trials, over 80 per cent of positive results have been falsely positive and have required invasive investigation. Estimates of the cost-effectiveness of screening for the Australian health system are not yet available and are essential. If the benefits of screening outweight the harms and costs, a successful screening program would require provision of screening infrastructure and appropriate information to target populations, quality control for screening tests and investigations, recall mechanisms to ensure appropriate follow-up of persons with positive results and the active participation of the Australian public and health practitioners.

Adult↗
PubMed2006

Embryonic stem cells as a source of differentiated neural cells for pharmacological screens.

The process of bringing a new pharmacologically active drug to market is laborious, time consuming, and costly. From drug discovery to safety assessment, new methods are constantly sought to develop faster and more efficient procedures to eliminate drugs from further investigation because of their limited effectiveness or high toxicity. Because in vitro cell assays are an important arm of this discovery process, it is therefore somewhat unsurprising that there is an emerging contribution of embryonic stem (ES) cell technology to this area. This technology utilizes the in vitro differentiation of ES cells into somatic cell target populations that, when coupled to the use of "lineage selection" protocols, allows for the production of infinite numbers of pure populations of the desired cells for both bioactivity and toxicological screens. Unlike the use of transformed cell lines, ES-derived cells remain karyotypically normal and therefore better reflect the potential responses of cells in vivo, and when selected are more homogeneous than those obtained using primary cultures. In this chapter we discuss the use of ES cell-derived somatic cells in pharmacological screens, with particular emphasis on neural cells, and describe the methods and protocols associated with the development of ES cell-derived neural cell assays.

Animals↗
PubMed2006

Modelling suicide risk in later life.

Affective disorder is generally regarded as the prominent risk factor for suicide in the old age population. Despite the large number of empirical studies available in the literature, there is no attempt in modelling the dynamics of an individual's level of suicide risk theoretically yet. In particular, a dynamic model which can simulate the time evolution of an individual's level of risk for suicide and provide quantitative estimates of the probability of suicide risk is still lacking. In the present study we apply the contingent claims analysis of credit risk modelling in the field of quantitative finance to derive a theoretical stochastic model for estimation of the probability of suicide risk in later life in terms of a signalling index of affective disorder. Our model is based upon the hypothesis that the current state of affective disorder of a patient can be represented by a signalling index and exhibits stochastic movement and that a threshold of affective disorder, which signifies the occurrence of suicide, exists. According to the numerical results, the implications of our model are consistent with the clinical findings. Hence, we believe that such a dynamic model will be essential to the design of effective suicide prevention strategies in the target population of older adults, especially in the primary care setting.

Aged↗
PubMed2006

Prevalence of prothrombin gene mutation (G-A 20210 A) in general population: a pilot study.

The objective of this study was to determine the prevalence of prothrombin gene mutation in a sample population from Pakistan. Two hundred apparently healthy unrelated adults (older than 18 years) were included in the study. The sample population comprised 100 Punjabis (male 50, female 50) and 100 Pathans (male 50, female 50). Patients with a history of previous thromboembolism were excluded from the study. Five milliliters (5 mL) of whole blood was drawn in an EDTA bottle. The DNA was extracted by the standard phenol-chloroform method. The DNA was amplified between exon number 14 and the 3'-untranslated region of the prothrombin gene by a polymerase chain reaction in a thermal cycler. Amplified products were digested overnight with HindIII at 37 degrees C. The digested products were electrophoresed on 6% polyacrylamide gel. The fragments were visualized by silver nitrate staining. A heterozygous wild type and an uncut amplified product were included in the electrophoresis strip for quality control. The wild type of DNA ran as a 350-bp fragment and internal control was cut as 550- and 150-bp fragments. The abnormal prothrombin gene was cut into 350-, 322-, and 28-bp fragments. Only two cases of heterozygous prothrombin gene mutation G-A 20210A were found in the sample studied, giving an overall carrier rate of 01% (95% CI 0.4-2.4%) in the target population. Prothrombin gene mutation is present in our population but at a lower frequency than in the white population.

Adult↗
PubMed2005

Ascertainment and evaluation of interval cancers in population-based mammography screening programmes: a collaborative study in four European centres.

OBJECTIVES: The purpose of the present study was to estimate the interval cancer (IC) rates in four population-based mammography screening programmes in four countries with different health-care environments, different access to cancer registry data, and different age groups of women invited. SETTING: The screening programmes in Coimbra (Portugal), Dublin (Ireland), Stockholm (Sweden), and Turin (Italy) participated in the study. METHODS: All cancer cases were searched for in cancer registries. IC rates and other outcome measures from the screening programmes were estimated and compared between the centres. Poisson regression model was used to estimate the proportional incidence based on IC rate in relation to expected total breast cancer incidence rate in the absence of screening. RESULTS: There was a more than tenfold difference in the number of invited women at the first round between the involved centres. The IC rates varied between 4.3 and 23.8 per 10,000 women screened. The levels of IC rates in relation to the estimated background incidence varied from 0.35 up to 0.46 depending on age groups involved in the programme, but did not differ significantly between three of the four involved centres. CONCLUSIONS: IC rates were quite similar between three of the four centres despite the differences in target population, invited ages, length of building-up of the programmes and different health-care organizations. Different access to complete cancer registry data is likely to explain the lower IC rates in the fourth centre.

Breast Neoplasms↗
PubMedDate not supplied

Alternative strategies for prevention of postmenopausal osteoporosis.

Osteoporosis is more readily prevented than treated, and early intervention with effective therapy would be expected to reduce significantly the impact of osteoporotic fractures among the aging population. For the postmenopausal female population, estrogen is the cornerstone of therapy, and multiple studies have demonstrated efficacy in reducing cortical and trabecular bone loss in the axial and peripheral skeleton. Alternative strategies for those who cannot, or will not, take estrogen and who can be documented to be at increased risk of osteoporosis, include calcium supplementation, progestogens, (particularly the 19-nortestosterone derivatives), calcitonin, diphosphonates, and anabolic steroids. All have been shown in some populations to reduce the rate of bone loss to a greater or lesser extent, although, overall, the data are as yet inconclusive. All regimes, with the exception of moderate calcium supplementation, have negative aspects to their use currently, and further research is required before a definitive alternative to estrogen for prevention of postmenopausal osteoporosis can be recommended. Only estrogens and calcitonin have Food and Drug Administration (FDA) approval for use in the treatment of osteoporosis. In the decision-making process for the woman at mid-life, risk factor assessment, although a poor quantitative tool for the individual patient, is the starting point for the evaluation of patients. Bone mass measurements play a crucial role in assisting the dubious patient (or physician) about the need for therapy. Estrogen use, however, is a more important issue for the postmenopausal female, with sequelae other than its effects on bone to be considered, including effects on cardiovascular disease, endometrial and breast cancer, which must be considered in the equation of risk-benefit. The greater the risks and costs of the intervention strategies available, the more important effective identification of the target population becomes. Estrogens, however, provide the most effective preventive treatment for osteoporosis. This review will deal primarily with the decision to introduce estrogen treatment, and the efficacy of estrogens,as well as alternative forms of prevention.

Estrogen Replacement Therapy↗
PubMedDate not supplied

Influence of age and purpose for testing on the cut-off selection of serological methods in bovine neosporosis.

The aim of this study was to investigate the need for different cut-off points, according to animal age and the purpose of testing, for two of the most widely used serological techniques in bovine neosporosis, IFAT and a crude antigen ELISA (Civtest, HIPRA). Therefore, the population reference sera used were defined using a combination of multiple criteria such as epidemiological/clinical and histopathological parameters and an immunoblot test. Firstly, foetuses and breeding cattle (heifers and cows) were considered as separate subpopulations for serological evaluation. Secondly, cut-off points for each serological technique (IFAT and ELISA) according to age group (foetuses and breeding cattle) and the different practical applications (detection of infection and abortion) were calculated following the receiver operating characteristics (ROC) analysis. Cut-off points were defined, for IFAT and ELISA for aborted breeding cattle and for IFAT alone in the case of the foetuses, assuming an equivalent cost of false positive and negative results. In infected breeding cattle, for IFAT and ELISA and in foetuses for ELISA, two possible cut-off values were obtained, one for a maximum sensitivity and one for a maximum specificity and the intervals of unclear results were defined. In this case, a cut-off value for equal sensitivity and specificity was also estimated. When cut-off points for infected breeding cattle, 1:100-1:250 for IFAT and 0.306-0.451 for ELISA were applied to a target population, optimal and similar negative and positive predictive values together with similar apparent and true prevalence results were observed suggesting the possibility of using both tests interchangeably.

Abortion, Veterinary↗
PubMed1992

Genetic control of murine hematopoietic stem cell pool sizes and cycling kinetics.

Bone marrow from each of two inbred mouse strains, C57BL/6J and DBA/2J, was highly enriched for stem cells using flow cytometry and was divided into two stem cell subpopulations using the mitochondrial dye rhodamine 123 (Rh-123). The Rh-123lo population was determined to be more primitive than Rh-123hi based on the expression of stem cell markers such as the c-kit protooncogene (stem cell factor receptor) and the Ly-6A/E stem cell antigen (Sca-1) as well as the lack of in vitro colony-forming ability. Compared to DBA/2J mice, marrow from the C57BL/6J strain consistently showed a higher proportion of "very primitive" (Rh-123lo) cells, suggesting that the sizes of functionally distinct stem cell subpopulations are maintained under precise genetic control. Marrow from both strains exposed to the cytotoxic drug 5-fluorouracil showed a dramatic increase in the proportion of Rh-123lo cells within 2 days as repopulation began. Marrow subpopulations returned to pretreatment proportions by the eighth day in DBA/2J mice but not until 14 days in C57BL/6J mice. This intrinsic difference in 5-fluorouracil recovery time was attributed to an increase rate of stem cell cycling in DBA/2J relative to C57BL/6J mice. When stem cell factor was injected into a C57BL/6J<-->DBA/2J allophenic mouse, blood cell chimerism shifted markedly but transiently toward the DBA/2J genotype, suggesting that the DBA/2J target population, because of an inherent kinetic advantage, was able to respond faster to the cytokine. A model is proposed that is based on these and our earlier observations to explain this strain-specific stem cell behavior and offer new insights into the genetic control of stem cell cycling and population dynamics.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2006

Urban ethnic minority women's attendance at health clinic vs. church based exercise programs.

Older, sedentary, urban-living, ethnic minority women are at high risk for preventable disease, but it is difficult to engage this population in health promotion efforts. This study tested two methods of engaging Hispanic and African American women, who were at high risk for cardiovascular disease, in a 10-week aerobic fitness program. The program was offered to 76 participants, in either a women's health clinic or a church. Attendance was the primary dependent variable and was recorded at each exercise session. Other variables, including the Baecke Questionnaire of Habitual Physical Activity, Fat Frequency Questionnaire, Self-Efficacy for Exercise Behaviors Scale, Social Support and Exercise Survey, and Psychological General Well-Being Schedule, were measured prior to the intervention, at the end of the 10-week program, and at 3-month follow-up. Age predicted attendance, independently of site. Women in the highest age quartile (50 - 70 years) attended more than twice as many exercise sessions compared to women in the lowest age quartile (17 - 27 years). The relationship between older age and attendance was particularly strong for Hispanic women. Church parishioners were primarily women over the age of 40, making it impossible to disentangle the relative effect of locale. These findings are relevant for clinicians who design exercise programs targeting older, ethnic, minority women. Administrators who design exercise programs for urban-living women should consider age of the target population when selecting the most conducive setting.

Adolescent↗