Eomesodermin, a target gene of Pou4f2, is required for retinal ganglion cell and optic nerve development in the mouse.

The mechanisms regulating retinal ganglion cell (RGC) development are crucial for retinogenesis and for the establishment of normal vision. However, these mechanisms are only vaguely understood. RGCs are the first neuronal lineage to segregate from pluripotent progenitors in the developing retina. As output neurons, RGCs display developmental features very distinct from those of the other retinal cell types. To better understand RGC development, we have previously constructed a gene regulatory network featuring a hierarchical cascade of transcription factors that ultimately controls the expression of downstream effector genes. This has revealed the existence of a Pou domain transcription factor, Pou4f2, that occupies a key node in the RGC gene regulatory network and that is essential for RGC differentiation. However, little is known about the genes that connect upstream regulatory genes, such as Pou4f2 with downstream effector genes responsible for RGC differentiation. The purpose of this study was to characterize the retinal function of eomesodermin (Eomes), a T-box transcription factor with previously unsuspected roles in retinogenesis. We show that Eomes is expressed in developing RGCs and is a mediator of Pou4f2 function. Pou4f2 directly regulates Eomes expression through a cis-regulatory element within a conserved retinal enhancer. Deleting Eomes in the developing retina causes defects reminiscent of those in Pou4f2(-/-) retinas. Moreover, myelin ensheathment in the optic nerves of Eomes(-/-) embryos is severely impaired, suggesting that Eomes regulates this process. We conclude that Eomes is a crucial regulator positioned immediately downstream of Pou4f2 and is required for RGC differentiation and optic nerve development.

A pure population of lung alveolar epithelial type II cells derived from human embryonic stem cells.

Alveolar epithelial type II (ATII) cells are small, cuboidal cells that constitute approximately 60% of the pulmonary alveolar epithelium. These cells are crucial for repair of the injured alveolus by differentiating into alveolar epithelial type I cells. ATII cells derived from human ES (hES) cells are a promising source of cells that could be used therapeutically to treat distal lung diseases. We have developed a reliable transfection and culture procedure, which facilitates, via genetic selection, the differentiation of hES cells into an essentially pure (>99%) population of ATII cells (hES-ATII). Purity, as well as biological features and morphological characteristics of normal ATII cells, was demonstrated for the hES-ATII cells, including lamellar body formation, expression of surfactant proteins A, B, and C, alpha-1-antitrypsin, and the cystic fibrosis transmembrane conductance receptor, as well as the synthesis and secretion of complement proteins C3 and C5. Collectively, these data document the successful generation of a pure population of ATII cells derived from hES cells, providing a practical source of ATII cells to explore in disease models their potential in the regeneration and repair of the injured alveolus and in the therapeutic treatment of genetic diseases affecting the lung.

The impact of cancer on the population of Salvador-Bahia, Brazil

The impact of cancer on the population of Salvador-Bahia, Brazil was studied using mortality data available from the Brazilian National Bureau of Vital Statistics. Average annual site, age, and gender specific and adjusted cancer mortality rates were determined for the years 1977-83 and contrasted with United States cancer mortality rates for the year of 1977. The accuracy of the cancer mortality rates generated by this research was determined by comparing the underlying causes of death as coded on death certificates to pathology reports and to hospital diagnosis of a sample of 966 deaths occurring in Salvador during the year of 1983. To further explore the information available on the death certificate, a population based decedent case control study was used to determine the relationship between type of occupation (proxy for exposure) and mortality by cancer sites known to be occupationally related.^ The rates in Salvador for cancer of the stomach, oral cavity, and biliary passages are, on average, two fold higher than the U.S. rates.^ The death certificate was found to be accurate for 65 percent of the 485 cancer deaths studied. Thirty five histologically confirmed cancer deaths were found in a random sample of 481 deaths from other causes. This means that, approximately 700 more deaths may be lost among the remainder 10,073 death certificates stating a cause other than cancer.^ In addition, despite the known limitations of decedent case-control studies, cancers of the oral cavity OR = 2.44, CI = 1.17-5.09, stomach OR = 2.31, CI = 1.18-4.52, liver OR = 4.06, CI = 1.27-12.99, bladder OR = 6.77, CI = 1.5-30.67, and lymphoma OR = 2.55, CI = 1.04-6.25 had elevated point estimates, for different age strata indicating an association between these cancers and occupations that led to exposure to petroleum and its derivates. ^

Behavioral and psychosocial factors associated with sexual risk in a population of crack cocaine users

The purpose of this dissertation was to examine the relationship between key psychosocial and behavioral components of the Transtheoretical Model and the Theory of Reasoned Action for sexual risk reduction in a population of crack cocaine smokers and sex workers, not in drug treatment. ^ The first study examined the results of an analysis of the association between two principal constructs in the Transtheoretical Model, the processes of change and the stages of change for condom use, in a high risk population. In the analysis of variance for all respondents, the overall F-test revealed that people in different stages have different levels of experiential process use, F(3,317) = 17.79, p = 0.0001 and different levels of behavioral process use, F(3,317) = 28.59, p = .0001. For the experiential processes, there was a significant difference between the precontemplation/contemplation stage, and both the action, and maintenance, stages.^ The second study explored the relationship between the Theory of Reasoned Action “beliefs” and the stages-of-change in the same population. In the analysis of variance for all participants, the results indicate that people in different stages did value the positive beliefs differently, F(3,502) = 15.38, p = .0001 but did not value the negative beliefs differently, F(3,502) = 2.08, p = .10. ^ The third study explored differences in stage-of-change by gender, partner type drug use, and HIV status. Three discriminant functions emerged, with a combined χ2(12) = 139.57, p = <.0001. The loading matrix of correlations between predictors and discriminant functions demonstrate that the strongest predictor for distinguishing between the precontemplation/contemplation stage and the preparation, action, and maintenance stages (first function) is partner type (.962). The loadings on the second discriminant function suggest that once partner type has been accounted for, ever having HIV/AIDS (.935) was the best predictor for distinguishing between the first three stages and the maintenance stage. ^ These studies demonstrate that behavioral change theories can contribute important insight to researchers and program planners attempting to alter HIV risk behavior in high-risk populations. ^

Intendedness of pregnancy among active duty women in the U.S. Army

Objective. The objective of this study was to determine the prevalence of unintended pregnancy and the association between social and demographic factors among a population of active duty women in the U.S. Army giving birth to viable infants at a U.S. Army hospital at Fort Hood, Texas. Prevalence of unintended pregnancy in this group was 50.9% (95% CI 44.0 to 57.9) with 36.3% being mistimed (95% CI 29.8 to 33.2) and 14.6% being unwanted (95% CI 10.2 to 20.1). A further 14.2% of the women experienced ambivalence (95% CI 9.8 to 19.6). ^ The study population was a cross-sectional group of active duty pregnant women who represent the target population of all female soldiers that deliver viable infants in the Army. Using a survey based on previous studies, intendedness of pregnancy at conception was retrospectively determined. Unintended births are further characterized as mistimed or unwanted. Demographic and other exposures were described bivariately. Associations were evaluated using measures of relative risk and chi-square analysis. ^ The results of the research indicate that in the study population, race/ethnicity is not associated with unintended pregnancy and non-commissioned officers had a lower rate of unintended pregnancy than other rank groupings. ^

Association between temperament and physical activity in a population of minority women

Physical activity has been, and remains, a significant public health issue. Thus, increasing physical activity has been identified as a top priority according to Healthy People 2010. Various behavioral variables have been associated with participation in physical activity, including the Type A behavior pattern (TABP). This study was a secondary data analysis of the Women On The Move pilot study data and examined the relationship between Type A behavior with physical activity. The study population consisted of fifty-six (56) adult minority women 40 years of age and above. The Thurstone Activity Scale was adapted for use in this study to measure TABP. Physical activity behavior was measured using an accelerometer (Computer Science Application, [CSA]) and a physical activity diary. All study questions were examined using multiple linear regression analysis. In all analyses age, household income, and level of education were entered as covariates. The results found no association with TABP and exercise or physical activity. More research involving a larger, more active study population is recommended in order to more precisely determine the relationship of TABP and physical activity. ^

Self-injury in a residential treatment population of children and adolescents

Objectives. The aim of this study was to describe the relationship between child-abuse and self-injury among children and adolescents living in a residential treatment center in a large urban area. ^ Methods. A retrospective study was conducted through a chart review of the residents who were placed at the center from 2003-2006. A total of 35 cases (with at least one documented incident of self-injury during placement at the residential treatment center) were age/gender matched with 35 controls (without at least one documented incident of self-injury during placement at the residential treatment center). ^ Results. In this study, the case subjects were far more likely to be victims of sexual abuse than were the controls (74.3% vs. 25.7%, respectively). Self-harm was found to be 9.5 times as frequent in the group that was exposed to sexual abuse in the source population (OR = 9.500 with a 95% CI = 2.292, 84.111). The difference was statistically significant (McNemar's test, x2 = 12.190 with 1 df. The two-tailed P value equals 0.0005). ^ Conclusion. These findings suggest that school-age and early-adolescent children who have a history of sexual abuse may engage in a variety of self-harming behaviors. Clinicians should consider a history of sexual abuse when working with self-harming children. ^

A cross sectional examination of risky sexual behaviors among a population of drug users

This study is a secondary data analysis that assesses the relationship between risky sexual behaviors and sexually transmitted infections (STIs) among drug users. This study analyzes data collected from drug users in the Houston Metropolitan area during 2004 and through August 2005, by researchers with the DASH (Drugs, AIDS, STDs and Hepatitis) project at The University of Texas at Houston School of Public Health. Specifically, the sexually transmitted infections that will be of interest in this proposed study are Human Immunodeficiency Virus (HIV) and Hepatitis B Virus (HBV). Risky sexual behaviors that will be examined include lack of condom use, sexual orientation, trading sex for drugs, trading sex for money, and number of male and female sexual partners in the last 4 weeks. ^ Unadjusted, gender, sexual orientation, number of recent male and female sex partners, and a history of injection drug use were all found to be significant independent variables that increased the odds of STI status. When included in an overall model, these variables significantly increased the odds of STI status, including HBV infection, HIV infection, and HBV/HIV co-infection. History of injection drug use was significant for both HBV and HBV/HIV co-infection, whereas a gay sexual orientation was significant for both HIV and HBV/HIV co-infection. Additionally, having excessive female sex partners was significant for HIV infection. This significant association increases the need for implementation of stronger intervention programs tailored to suit this population's needs such as a combination of drug and sexually transmitted disease (STD) treatment. ^ The importance of these findings is that they establish the strength of associations between the previously mentioned risky sexual behaviors and STI status among drug users. This is crucial for assessing future risk of infection as well as for serving as a necessary component in intervention and treatment programs both for drug use and STIs. ^

Theory of uncertainty in illness in patients with cancer of unknown primary origin: Structure providers as antecedents of uncertainty in a population of cancer patients with an unknown primary diagnosis

Uncertainty has been found to be a major component of the cancer experience and can dramatically affect psychosocial adaptation and outcomes of a patient's disease state (McCormick, 2002). Patients with a diagnosis of Carcinoma of Unknown Primary (CUP) may experience higher levels of uncertainty due to the unpredictability of current and future symptoms, limited treatment options and an undetermined life expectancy. To date, only one study has touched upon uncertainty and its' effects on those with CUP but no information exists concerning the effects of uncertainty regarding diagnosis and treatment on the distress level and psychosocial adjustment of this population (Parker & Lenzi, 2003). ^ Mishel's Uncertainty in Illness Theory (1984) proposes that uncertainty is preceded by three variables, one of which being Structure Providers. Structure Providers include credible authority, the degree of trust and confidence the patient has with their doctor, education and social support. It was the goal of this study to examine the relationship between uncertainty and Structure Providers to support the following hypotheses: (1) There will be a negative association between credible authority and uncertainty, (2) There will be a negative association between education level and uncertainty, and (3) There will be a negative association between social support and uncertainty. ^ This cross-sectional analysis utilized data from 219 patients following their initial consultation with their oncologist. Data included the Mishel Uncertainty in Illness Scale (MUIS) which was used to determine patients' uncertainty levels, the Medical Outcomes Study-Social Support Scale (MOSS-SSS) to assess patients, levels of social support, the Patient Satisfaction Questionnaire (PSQ-18) and the Cancer Diagnostic Interview Scale (CDIS) to measure credible authority and general demographic information to assess age, education, marital status and ethnicity. ^ In this study we found that uncertainty levels were generally higher in this sample as compared to other types of cancer populations. And while our results seemed to support most of our hypothesis, we were only able to show significant associations between two. The analyses indicated that credible authority measured by both the CDIS and the PSQ was a significant predictor of uncertainty as was social support measured by the MOSS-SS. Education has shown to have an inconsistent pattern of effect in relation to uncertainty and in the current study there was not enough data to significantly support our hypothesis. ^ The results of this study generally support Mishel's Theory of Uncertainty in Illness and highlight the importance of taking into consideration patients, psychosocial factors as well as employing proper communication practices between physicians and their patients.^

A survey of statural changes with age in the adult population of the United States

A study of the patterns of height loss with age in the Anglo, black, and Mexican-American populations of the United States has been undertaken. The study was based on data gathered by the United States Public Health Service in the Second National Health and Nutrition Examination Survey and the Hispanic Health and Nutrition Examination Survey. Estimates of height loss were obtained by subtracting present stature from a calculated maximum attained height derived from sex- and race/ethnic-specific regression equations relating stature to subischial length. Anglo women have greater height losses than Anglo, black, or Mexican-American males, and black or Mexican-American females. Between 24 and 74 years of age, Anglo women average 3.8 cm. loss in stature. The black populations lose less height than Anglos or Mexican-Americans. Mexican-Americans lose less height than Anglos from 24 to 54 years and then have a greatly increased height loss so that by age 74 their total height loss is the same as Anglos. Standing height, sitting height, body mass index, and the Poverty Index were found to be negatively correlated with height loss. Age was positively correlated to height loss. The most important determinants of the magnitude of height loss with age were sex and ethnicity. ^

Ethnicity as a risk factor for diabetes incidence in a population of diagnosed hypertensives

Significant racial/ethnic differences exist in prevalence of hypertension (HTN) and non-insulin dependent diabetes mellitus (NIDDM). Hypertension is more common in diabetics than in non-diabetics, and an etiologic link between the two conditions has been proposed. Since there are few longitudinal studies of persons with both HTN and NIDDM, a retrospective cohort study was conducted to determine if ethnicity (Black, Hispanic (Mexican-American), and non-Hispanic White) was related to NIDDM incidence in a low-SES, multi-ethnic clinic population of diagnosed hypertensives. Two thousand nine hundred forty-one hypertensives free of NIDDM at baseline were followed for up to 10 years. Mean baseline age was 56 $\pm$ 12 years, M:F percent was 33:67, and Black:Hispanic:White percent was 63:17:20. There were 236 incident cases of NIDDM. In Cox proportional hazards analysis, the risk of developing NIDDM over 10 years was not related to ethnicity after controlling for significant covariates, including age, baseline blood glucose and body mass index (adjusted RR for Blacks compared to Whites =.82, 95 percent CI =.57-1.18; adjusted RR for Hispanics compared to Whites =.84, 95 percent CI =.51-1.38). This result contrasts with the increased risk of NIDDM among Blacks and Hispanics compared to Whites found in the general population. The study suggests that a diagnosis of hypertension equalizes the risk of developing NIDDM among the three ethnic groups. ^

THE RELATIONSHIP BETWEEN SERUM CHOLESTEROL AND CANCER INCIDENCE IN THE POPULATION OF THE HYPERTENSION DETECTION AND FOLLOW-UP PROGRAM

The relationship between serum cholesterol and cancer incidence was investigated in the population of the Hypertension Detection and Follow-up Program (HDFP). The HDFP was a multi-center trial designed to test the effectiveness of a stepped program of medication in reducing mortality associated with hypertension. Over 10,000 participants, ages 30-69, were followed with clinic and home visits for a minimum of five years. Cancer incidence was ascertained from existing study documents, which included hospitalization records, autopsy reports and death certificates. During the five years of follow-up, 286 new cancer cases were documented. The distribution of sites and total number of cases were similar to those predicted using rates from the Third National Cancer Survey. A non-fasting baseline serum cholesterol level was available for most participants. Age, sex, and race specific five-year cancer incidence rates were computed for each cholesterol quartile. Rates were also computed by smoking status, education status, and percent ideal weight quartiles. In addition, these and other factors were investigated with the use of the multiple logistic model.^ For all cancers combined, a significant inverse relationship existed between baseline serum cholesterol levels and cancer incidence. Previously documented associations between smoking, education and cancer were also demonstrated but did not account for the relationship between serum cholesterol and cancer. The relationship was more evident in males than females but this was felt to represent the different distribution of occurrence of specific cancer sites in the two sexes. The inverse relationship existed for all specific sites investigated (except breast) although a level of statistical significance was reached only for prostate carcinoma. Analyses after exclusion of cases diagnosed during the first two years of follow-up still yielded an inverse relationship. Life table analysis indicated that competing risks during the period of follow-up did not account for the existence of an inverse relationship. It is concluded that a weak inverse relationship does exist between serum cholesterol for many but not all cancer sites. This relationship is not due to confounding by other known cancer risk factors, competing risks or persons entering the study with undiagnosed cancer. Not enough information is available at the present time to determine whether this relationship is causal and further research is suggested. ^

SEVERITY OF IRON DEFICIENCY ANEMIA AND ITS RELATIONSHIP TO GROWTH AND MORBIDITY IN A POPULATION OF PRE-SCHOOLERS IN RURAL GUATEMALA (IRON DEFICIENCY, MORBIDITY, GROWTH)

The objectives of this study were to determine the nature of the relationship between severity of iron deficiency anemia, response to iron treatment, respiratory and gastrointestinal illness and weight change. Seventy-five pre-school children from rural Guatemala received daily oral iron therapy for an eleven week period, and were classified into one of three groups having different degrees of iron deficiency anemia. Anthropometric and biochemical data were collected prior and after iron treatment; morbidity data were collected throughout the period of treatment. The outcome variables were percentage weight change, percentage of total days ill with any type of symptom, percentage of total days ill with gastrointestinal symptoms, percentage of total days ill with respiratory symptoms, percentage of total days ill with combination syndrome symptoms. Age, sex and socio-economic status, were independent of any of the independent or outcome variables used. On the other hand, the level of hemoglobin covaried with the height of the children, the smallest children were the most severely anemic. The relationships between hemoglobin levels and weight change, frequency of morbidity (gastrointestinal, respiratory and combination syndrome) and total number of days ill with any symptomatology were investigated. No statistical significance was found in these analyses except when contrasting children with normal hemoglobin levels to iron deficient children, where the findings indicated the normal children experienced more gastrointestinal morbidity. The same relationship were again analyzed but including delta hemoglobin as covariate in the analysis, this latter one was found to be significant at 7% when the percentage of days ill from gastrointestinal morbidity was tested against the hemoglobin groups. The relationship found indicates that, all other covariates accounted for, the percentage of days ill from gastrointestinal morbidity will decrease approximately 1% for each 1% increase in delta of hemoglobin. ^

Cervical cancer screening in Hispanic women as compared with other ethnic groups on an urban campus

Although Pap screening has decreased morbidity and mortality from cervical cancer, reported statistics indicate that among ethnic groups, Hispanic women are one of the least likely to follow screening guidelines. Human papillomavirus (HPV), a major risk factor for cervical cancer, as well as pre-cancerous lesions, may be detected by early Pap screening. With a reported 43% prevalence of HPV infection in college women, regular Pap screening is important. The purpose of this descriptive, cross-sectional survey was to examine self-reported cervical cancer screening rates in a target population of primarily Mexican-American college women, and to discover if recognized correlates for screening behavior explained differences in screening rates between this and two other predominant groups on the University of Houston Downtown campus, non-Hispanic white and African-American. The sample size consisted of 613 women recruited from summer 2003 classes. A survey, adapted from an earlier El Paso study, and based on constructs of the Health Belief Model (HBM), was administered to women ages 18 and older. It was found that although screening rates were similar across ethnic groups, overall, the Hispanic group obtained screening less frequently, though this did not reach statistical significance. However, a significant difference in lower screening rates was found in Mexican American women ages <25. Additionally, of the predicted correlates, the construct of perceived barriers from the HBM was most significant for the Mexican American group for non-screening. For all groups, knowledge about cervical cancer was negatively correlated with ever obtaining Pap screening and screening within the past year. This implies that if health counseling is given at the time of women's screening visits, both adherence to appropriate screening intervals and risk factor avoidance may be more likely. Studies such as these are needed to address both screening behaviors and likelihood of follow-up for abnormal results in populations of multicultural, urban college women. ^