The contributions of the amygdala, orbital frontal cortex and hippocampal formation to primate social cognition

Deficits in social cognition are prominent symptoms of many human psychiatric disorders, but the origin of such deficits remains largely unknown. To further current knowledge regarding the neural network mediating social cognition, the present research program investigated the individual contributions of two temporal lobe structures, the amygdala and hippocampal formation, and one frontal lobe region, the orbital frontal cortex (Areas 11 and 13), to primate social cognition. Based on previous research, we hypothesized that the amygdala, hippocampal formation and orbital frontal cortex contribute significantly to the formation of new social relationships, but less to the maintenance of familiar ones. ^ Thirty-six male rhesus macaques (Macaca mulatta) served as subjects, and were divided into four experimental groups: Neurotoxic amygdala lesion (A-ibo, n = 9), neurotoxic or aspiration orbital frontal cortex lesion (O, n = 9), neurotoxic hippocampal formation lesion (H-ibo, n = 9) or sham-operated control (C, n = 9). Six social groups (tetrads) were created, each containing one member from each experimental group. The effect of lesion on established social relationships was assessed during pre- and post-surgical unrestrained social interactions, whereas the effect of lesion on the formation of new relationships was assessed during an additional phase of post-surgical testing with shuffled tetrad membership. Results indicated that these three neural structures each contribute significantly to both the formation and maintenance of social relationships. Furthermore, the amygdala appears to primarily mediate normal responses to threatening social signals, whereas the orbital frontal cortex plays a more global role in social cognition by mediating responses to both threatening and affiliative social signals. By contrast, the hippocampal formation seems to contribute to social cognition indirectly by providing access to previous experience during social judgments. ^ These conclusions were further investigated with three experiments that measured behavioral and physiological (stress hormone) reactivity to threatening stimuli, and three additional experiments that measured subjects' ability to flexibly alter behavioral responses depending on the incentive value of a food reinforcer. Data from these six experiments further confirmed and strengthened the three conclusions originating from the social behavior experiments and, when combined with the current literature, helped to formulate a simple, but testable, theoretical model of primate social cognition. ^

Comparing the factorial structure, invariance, and predictive validity of transtheoretical model constructs for alcohol use across restricted and unrestricted settings

With substance abuse treatment expanding in prisons and jails, understanding how behavior change interacts with a restricted setting becomes more essential. The Transtheoretical Model (TTM) has been used to understand intentional behavior change in unrestricted settings, however, evidence indicates restrictive settings can affect the measurement and structure of the TTM constructs. The present study examined data from problem drinkers at baseline and end-of-treatment from three studies: (1) Project CARE (n = 187) recruited inmates from a large county jail; (2) Project Check-In (n = 116) recruited inmates from a state prison; (3) Project MATCH, a large multi-site alcohol study had two recruitment arms, aftercare (n = 724 pre-treatment and 650 post-treatment) and outpatient (n = 912 pre-treatment and 844 post-treatment). The analyses were conducted using cross-sectional data to test for non-invariance of measures of the TTM constructs: readiness, confidence, temptation, and processes of change (Structural Equation Modeling, SEM) across restricted and unrestricted settings. Two restricted (jail and aftercare) and one unrestricted group (outpatient) entering treatment and one restricted (prison) and two unrestricted groups (aftercare and outpatient) at end-of-treatment were contrasted. In addition TTM end-of-treatment profiles were tested as predictors of 12 month drinking outcomes (Profile Analysis). Although SEM did not indicate structural differences in the overall TTM construct model across setting types, there were factor structure differences on the confidence and temptation constructs at pre-treatment and in the factor structure of the behavioral processes at the end-of-treatment. For pre-treatment temptation and confidence, differences were found in the social situations factor loadings and in the variance for the confidence and temptation latent factors. For the end-of-treatment behavioral processes, differences across the restricted and unrestricted settings were identified in the counter-conditioning and stimulus control factor loadings. The TTM end-of-treatment profiles were not predictive of drinking outcomes in the prison sample. Both pre and post-treatment differences in structure across setting types involved constructs operationalized with behaviors that are limited for those in restricted settings. These studies suggest the TTM is a viable model for explicating addictive behavior change in restricted settings but calls for modification of subscale items that refer to specific behaviors and caution in interpreting the mean differences across setting types for problem drinkers. ^

Health education intervention to reduce risk of infectious disease transmission among community health workers and their clients

Indigent and congregate-living populations have high susceptibilities for disease and pose a higher risk for disease transmission to family, friends and to persons providing services to these populations. The adoption of basic infection control, personal hygiene, safe food handling and simple engineering practices will reduce the risk of infectious disease transmission to, from and among indigent and congregate-living populations. ^ The provision of social services, health promotion activities and other support services to indigent and congregate-living populations is an important aspect of many public health-related governmental, community-based and other medical care provider agencies. ^ In the interest of protecting the health of indigent and congregate-living populations, of personnel from organizations providing services to these populations and of the general community, an educational intervention is warranted to prevent the spread of blood-borne, air-borne, food-borne and close contact-borne infectious diseases. ^ An educational presentation was provided to staff from a community-based organization specializing in providing housing, health education, foodstuffs and meals and support services to disabled, low-income, homeless and HIV-infected individuals. The educational presentation delivered general best practices and standard guidelines. A pre and post test were administered to determine and measure knowledge pertinent to controlling the spread of infectious diseases between and among homeless shelter-living clients and between clients and the organization's staff. ^ Comparing pre-test and post-test results revealed areas of knowledge currently held by staff and other areas that staff would benefit from additional educational seminars and training. ^

A formative evaluation of the American Diabetes Association's Choosing Health and Sensible Exercise childhood obesity intervention

Background. The increasing prevalence of overweight among youth in the United States, and the parallel rise in related medical comorbidities has led to a growing need for efficient weight-management interventions. Purpose. The aim of this study was to evaluate the effects of the Choosing Health and Sensible Exercise (C.H.A.S.E.) childhood obesity prevention program on Body Mass Index (BMI), physical activity and dietary behaviors. Methods. This study utilized de-identified data collected during the fall 2006 session of the C.H.A.S.E. program. A total of 65 students at Woodview Elementary School and Deepwater Elementary School participated in this intervention. The C.H.A.S.E. program is a 10-week obesity prevention program that focuses on nutrition and physical activity education. Collection of height and weight data, and a health behavior survey was conducted during the first and last week of the intervention. Paired t-tests were used to determine statistically significant differences between pre- and post-intervention measurements. One-way analysis of variance was used to adjust for potential confounders, such as gender, age, BMI category ("normal weight", "at risk overweight", or "overweight"), and self-reported weight loss goals. Data were analyzed using STATA, v. 9.2. Results. A significant decrease in mean BMI (p< 0.05) was found after the 10-week intervention. While the results were statistically significant for the group as a whole, changes in BMI were not significant when stratified by age, sex, or ethnicity. The mean overall scores for the behavior survey did not change significantly pre- and post-intervention; however, significant differences were found in the dietary intention scale, indicating that students were more likely to intend to make healthier food choices (p<0.05). No statistically significant decreases in BMI were found when stratified for baseline BMI-for-age percentiles or baseline weight loss efforts (p>0.05). Conclusion. The results of this evaluation provide information that will be useful in planning and implementing an effective childhood obesity intervention in the future. Changes in the self-reported dietary intentions and BMI show that the C.H.A.S.E. program is capable of modifying food choice selection and decreasing BMI. Results from the behavior questionnaire indicate that students in the intervention program were making changes in a positive direction. Future implementation of the C.H.A.S.E. program, as well as other childhood obesity interventions, may want to consider incorporating additional strategies to increase knowledge and other behavioral constructs associated with decreased BMI. In addition, obesity prevention programs may want to increase parental involvement and increase the dose or intensity of the intervention. ^

Determining the feasibility and acceptability of a garden-based nutrition curriculum for preschoolers

Obesity rates around the nation have risen to epidemic proportions. Rates of childhood obesity are at very high levels with 24.4% of preschool-aged children in the U.S. currently considered as overweight or obese. The percentage of childhood obesity is much higher in the southern part of the United States as compared to the rest of the nation. Minority populations, especially African American and Hispanic, are affected more than other ethnic groups. Obesity prevention programs are needed targeting young children <6 years of age from minority populations. Currently, there are few obesity prevention programs that have been implemented and evaluated in children <6 years of age. Gardening programs have been successful in improving the health status of elementary school children by increasing fruit and vegetable intake and increasing preferences for healthier food choices. However, there is no evidence of the feasibility and acceptability of a garden-based obesity prevention program among preschoolers. This pretest study, a classroom-based gardening curriculum program with 16 lesson plans and coordinating activities for preschool age children (3-5 years old) enrolled in Head Start, provides the opportunity to address this need. The study included 103 preschoolers from two centers and 9 teachers or teachers' aides. Qualitative data on feasibility and acceptability was collected from process evaluation forms of individual lesson plans and focus groups with teachers. Teacher questionnaires assessed individual teacher characteristics and provided feedback regarding the curriculum. Quantitative measures of teachers' self-efficacy, attitudes, and knowledge pertaining to nutrition were analyzed from pre and post-test surveys. Results revealed this preschool garden-based nutrition curriculum was both feasible and acceptable. The program improved teacher's self-efficacy, knowledge, and attitudes about nutrition, with teacher's confidence in ability to teach a gardening curriculum increasing from a mean score of 2.14 to 3.00 from pre to post test (P value = 0.0046). These results indicate implementing garden-based nutrition lessons within preschools is achievable. Employing garden-based nutrition lessons in the classroom is the first step in teaching children about nutrition and gardening concepts. Constructing gardening beds for more hands-on learning is the next proposed step in the larger parent study of this program.^

The role of workplace absence as an organizational mechanism in predicting employee alcohol and drug disorders

Background. EAP programs for airline pilots in companies with a well developed recovery management program are known to reduce pilot absenteeism following treatment. Given the costs and safety consequences to society, it is important to identify pilots who may be experiencing an AOD disorder to get them into treatment. ^ Hypotheses. This study investigated the predictive power of workplace absenteeism in identifying alcohol or drug disorders (AOD). The first hypothesis was that higher absenteeism in a 12-month period is associated with higher risk that an employee is experiencing AOD. The second hypothesis was that AOD treatment would reduce subsequent absence rates and the costs of replacing pilots on missed flights. ^ Methods. A case control design using eight years (time period) of monthly archival absence data (53,000 pay records) was conducted with a sample of (N = 76) employees having an AOD diagnosis (cases) matched 1:4 with (N = 304) non-diagnosed employees (controls) of the same profession and company (male commercial airline pilots). Cases and controls were matched on the variables age, rank and date of hire. Absence rate was defined as sick time hours used over the sum of the minimum guarantee pay hours annualized using the months the pilot worked for the year. Conditional logistic regression was used to determine if absence predicts employees experiencing an AOD disorder, starting 3 years prior to the cases receiving the AOD diagnosis. A repeated measures ANOVA, t tests and rate ratios (with 95% confidence intervals) were conducted to determine differences between cases and controls in absence usage for 3 years pre and 5 years post treatment. Mean replacement costs were calculated for sick leave usage 3 years pre and 5 years post treatment to estimate the cost of sick leave from the perspective of the company. ^ Results. Sick leave, as measured by absence rate, predicted the risk of being diagnosed with an AOD disorder (OR 1.10, 95% CI = 1.06, 1.15) during the 12 months prior to receiving the diagnosis. Mean absence rates for diagnosed employees increased over the three years before treatment, particularly in the year before treatment, whereas the controls’ did not (three years, x = 6.80 vs. 5.52; two years, x = 7.81 vs. 6.30, and one year, x = 11.00cases vs. 5.51controls. In the first year post treatment compared to the year prior to treatment, rate ratios indicated a significant (60%) post treatment reduction in absence rates (OR = 0.40, CI = 0.28, 0.57). Absence rates for cases remained lower than controls for the first three years after completion of treatment. Upon discharge from the FAA and company’s three year AOD monitoring program, case’s absence rates increased slightly during the fourth year (controls, x = 0.09, SD = 0.14, cases, x = 0.12, SD = 0.21). However, the following year, their mean absence rates were again below those of the controls (controls, x = 0.08, SD = 0.12, cases, x¯ = 0.06, SD = 0.07). Significant reductions in costs associated with replacing pilots calling in sick, were found to be 60% less, between the year of diagnosis for the cases and the first year after returning to work. A reduction in replacement costs continued over the next two years for the treated employees. ^ Conclusions. This research demonstrates the potential for workplace absences as an active organizational surveillance mechanism to assist managers and supervisors in identifying employees who may be experiencing or at risk of experiencing an alcohol/drug disorder. Currently, many workplaces use only performance problems and ignore the employee’s absence record. A referral to an EAP or alcohol/drug evaluation based on the employee’s absence/sick leave record as incorporated into company policy can provide another useful indicator that may also carry less stigma, thus reducing barriers to seeking help. This research also confirms two conclusions heretofore based only on cross-sectional studies: (1) higher absence rates are associated with employees experiencing an AOD disorder; (2) treatment is associated with lower costs for replacing absent pilots. Due to the uniqueness of the employee population studied (commercial airline pilots) and the organizational documentation of absence, the generalizability of this study to other professions and occupations should be considered limited. ^ Transition to Practice. The odds ratios for the relationship between absence rates and an AOD diagnosis are precise; the OR for year of diagnosis indicates the likelihood of being diagnosed increases 10% for every hour change in sick leave taken. In practice, however, a pilot uses approximately 20 hours of sick leave for one trip, because the replacement will have to be paid the guaranteed minimum of 20 hour. Thus, the rate based on hourly changes is precise but not practical. ^ To provide the organization with practical recommendations the yearly mean absence rates were used. A pilot flies on average, 90 hours a month, 1080 annually. Cases used almost twice the mean rate of sick time the year prior to diagnosis (T-1) compared to controls (cases, x = .11, controls, x = .06). Cases are expected to use on average 119 hours annually (total annual hours*mean annual absence rate), while controls will use 60 hours. The cases’ 60 hours could translate to 3 trips of 20 hours each. Management could use a standard of 80 hours or more of sick time claimed in a year as the threshold for unacceptable absence, a 25% increase over the controls (a cost to the company of approximately of $4000). At the 80-hour mark, the Chief Pilot would be able to call the pilot in for a routine check as to the nature of the pilot’s excessive absence. This management action would be based on a company standard, rather than a behavioral or performance issue. Using absence data in this fashion would make it an active surveillance mechanism. ^

A summative evaluation of a HIV/AIDS Early Childhood Care, Education and Development Teacher Training Workshop in Mongu, Zambia

Objective. To conduct a summative evaluation of an Early Childhood Care, Education and Development (ECCED) Teacher Training Workshop in Mongu, Zambia by assessing changes in knowledge, attitudes and intent to use the information. ^ Study design. A matched cohort survey design was used with additional qualitative data collected by structured observation of workshop sessions, daily facilitator and participant debriefs and participant interviews. ^ Results. Matching pre and post tests were completed by 27 individuals in addition to daily debriefs, structured workshop observation and participant interviews with 22% of the group. The participant population was predominantly female individuals aged 15-44 years old that had completed high school and additional post-secondary training, been teaching children aged 0 – 8 years for 2-5 years in the Western Province and received other HIV/AIDS and ECCED education. Pre-tests indicated a strong understanding of ECCED principles and misconceptions regarding HIV transmission, prevention and the disease's impact on early childhood development. The workshop was found to significantly increase the participants' knowledge of topics covered by the curriculum (paired t-test, N=27, p = 0.004, 95% CI 1.8, 8.6). Participants began with a more limited understanding of HIV/AIDS than ECCED, but the mean gain was much greater at 7.4 +/- 12.3 points. Significantly more participants believed at post-test that HIV/AIDS education should increase for future educators. The 77.8% of participants that increased their knowledge scores at post-test expressed significantly less fear of having a child with HIV/AIDS in the classroom (Independent Samples t-test, N= 27, p = 0.011). Overall participant fear decreased 15.5%. 92.6% and 88.9% of participants planned at post-test to respectively use and share the taught information in their daily professional lives and reported on innovative strategies to communicate with the community. ^ Conclusions. Teacher training workshops can significantly increase HIV/AIDS awareness and promote positive attitudes in educators working with children affected by HIV/AIDS. Using participant suggested teaching techniques such as poems and songs and translating the materials to the local language could assist future facilitators to both culturally and professionally relate to the workshop audience as well as increase participant capacity to share the information with the local community. ^

Use of tabletop exercises for disaster preparedness training

Background. In public health preparedness, disaster preparedness refers to the strategic planning of responses to all types of disasters. Preparation and training for disaster response can be conducted using different teaching modalities, ranging from discussion-based programs such as seminars, drills and tabletop exercises to more complex operation-based programs such as functional exercises and full-scale exercises. Each method of instruction has its advantages and disadvantages. Tabletop exercises are facilitated discussions designed to evaluate programs, policies, and procedures; they are usually conducted in a classroom, often with tabletop props (e.g. models, maps or diagrams). ^ Objective. The overall goal of this project was to determine whether tabletop exercises are effective teaching modalities for disaster preparedness, with an emphasis on intentional chemical exposure. ^ Method. The target audience for the exercise was the Medical Reserve Brigade of the Texas State Guard, a group of volunteer healthcare providers and first responders who prepare for response to local disasters. A new tabletop exercise was designed to provide information on the complex, interrelated organizations within the national disaster preparedness program that this group would interact with in the event of a local disaster. This educational intervention consisted of a four hour multipart program that included a pretest of knowledge, lecture series, an interactive group discussion using a mock disaster scenario, a posttest of knowledge, and a course evaluation. ^ Results. Approximately 40 volunteers attended the intervention session; roughly half (n=21) had previously participated in a full scale drill. There was an 11% improvement in fund of knowledge between the pre- and post-test scores (p=0.002). Overall, the tabletop exercise was well received by those with and without prior training, with no significant differences found between these two groups in terms of relevance and appropriateness of content. However, the separate components of the tabletop exercise were variably effective, as gauged by written text comments on the questionnaire. ^ Conclusions. Tabletop exercises can be a useful training modality in disaster preparedness, as evidenced by improvement in knowledge and qualitative feedback on its value. Future offerings could incorporate recordings of participant responses during the drill, so that better feedback can be provided to them. Additional research should be conducted, using the same or similar design, in different populations that are stakeholders in disaster preparedness, so that the generalizability of these findings can be determined.^

Process evaluation of intervention program for prevention of early sexual activity and alcohol use among Hispanic teenagers

Hispanic teens are a high-risk population for initiation of early sexual activity and alcohol use which in turn has numerous social and health consequences. One strategy to address prevention of these behaviors is to implement a capacity building intervention that promotes parent child communication, encompasses their cultural values and community participation. This study describes the process evaluation of a pilot intervention program amongst Hispanic teens and their families living along the Texas-Mexico border. “Girls Lets Talk” is a small group intervention with 10-14 year old teens and their female adult family members that involves education regarding effects of alcohol use and sexual activity as well as activities for monitoring and refusal skills to prevent risky behaviors. Two waves of the program each consisting of at least seven mother daughter dyads were conducted. During the designing process, community advisory board meetings and focus groups were held to review course materials and ensure they were appropriate to the Mexican American culture. Parent and adolescent surveys were administered at the beginning and end of the intervention to assess for psychosocial outcome variables. All sessions received high mean satisfactory scores (mean of 4.00 or better on a five point scale) for both adult and adolescent participants. Qualitative feedback was obtained via debriefing sessions to evaluate experience as well as alter recruitment strategies. A Wilcoxon Sign Rank analysis of the pre and post intervention surveys was done that showed significant changes in some outcome variables such as intentions and confidence for monitoring behaviors for adults and beliefs regarding sexual activity. “Girls Lets Talk” is a promising example of how a process evaluation plan can help develop a theory based health promotion program using the community based participatory research approach. The intervention may also be effective in altering intentions and enhancing self-efficacy among parents and teens in order to decrease risky behaviors such as early sexual activity and alcohol use.^

Public service use by residents of Jackson Hinds Gardens before and after enrollment

Homelessness is associated with high use of public services such as health care and criminal justice services. Intervention designs to reverse homelessness have broadly fallen into two categories: either standard care which employs requisitely addressing the causes of homelessness, or housing first, which emphasizes provision of permanent housing without requisitely addressing the causes of homelessness. Multiple cities have recently commenced housing first interventions. Locally, Houston’s first housing first development is the Jackson Hinds Gardens project. The purpose of this study is to analyze the public service use of residents of housing first in Houston. Residents of Jackson Hinds Gardens who have been enrolled for at least 6 months were evaluated for public service use for an equal amount of time preceding and during their residence at Jackson Hinds. Resident interactions with county health services and criminal justice entities were determined by electronic database searches; these data were supplemented by life experience interview data. Service usage values pre- and post-enrollment at Jackson Hinds Gardens were compared by paired t-test analyses. We found that ER and inpatient usage decreased following enrollment in Jackson Hinds, although these reductions were not significant. In contrast, outpatient care and number of medications significantly increased following enrollment. These analyses inform on the effects of housing first in another major city, as well as informing the ethical considerations regarding housing first versus standard care. ^

Selection of body fat distribution indices in adults and associations with plasma lipid metabolism variables

Body fat distribution is a cardiovascular health risk factor in adults. Body fat distribution can be measured through various methods including anthropometry. It is not clear which anthropometric index is suitable for epidemiologic studies of fat distribution and cardiovascular disease. The purpose of the present study was to select a measure of body fat distribution from among a series of indices (those traditionally used in the literature and others constructed from the analysis) that is most highly correlated with lipid-related variables and is independent of overall fatness. Subjects were Mexican-American men and women (N = 1004) from a study of gallbladder disease in Starr County, Texas. Multivariate associations were sought between lipid profile measures (lipids, lipoproteins, and apolipoproteins) and two sets of anthropometric variables (4 circumferences and 6 skinfolds). This was done to assess the association between lipid-related measures and the two sets of anthropometric variables and guide the construction of indices.^ Two indices emerged from the analysis that seemed to be highly correlated with lipid profile measures independent of obesity. These indices are: 2*arm circumference-thigh skinfold in pre- and post-menopausal women and arm/thigh circumference ratio in men. Next, using the sum of all skinfolds to represent obesity and the selected body fat distribution indices, the following hypotheses were tested: (1) state of obesity and centrally/upper distributed body fat are equally predictive of lipids, lipoproteins and apolipoproteins, and (2) the correlation among the lipid-related measures is not altered by obesity and body fat distribution.^ With respect to the first hypothesis, the present study found that most lipids, lipoproteins and apolipoproteins were significantly associated with both overall fatness and anatomical location of body fat in both sex and menopausal groups. However, within men and post-menopausal women, certain lipid profile measures (triglyceride and HDLT among post-menopausal women and apos C-II, CIII, and E among men) had substantially higher correlation with body fat distribution as compared with overall fatness.^ With respect to the second hypothesis, both obesity and body fat distribution were found to alter the association among plasma lipid variables in men and women. There was a suggestion from the data that the pattern of correlations among men and post-menopausal women are more comparable. Among men correlations involving apo A-I, HDLT, and HDL$\sb2$ seemed greatly influenced by obesity, and A-II by fat distribution; among post-menopausal women correlations involving apos A-I and A-II were highly affected by the location of body fat.^ Thus, these data point out that not only can obesity and fat distribution affect levels of single measures, they also can markedly influence the pattern of relationship among measures. The fact that such changes are seen for both obesity and fat distribution is significant, since the indices employed were chosen because they were independent of one another. ^

For health's sake: Cervical and breast cancer screening

African-Americans make up twelve percent of the United States population, yet they experience morbidity and mortality at a rate that, in some cases, is disproportionate to their numbers. There are numerous health areas, including cancer, in which disparities exist. There are also numerous reasons which have been suggested to explain the high rates of cancer morbidity and mortality experienced by African-Americans. Among the reasons given to explain these differences are lack of knowledge and lack of access to medical care (1). This study sought to increase the knowledge, attitudes, and behavioral intentions of African-American women attending a Baptist church in Houston with regard to cervical cancer, breast cancer, Pap smear, and mammography. It was hypothesized that a church-based cancer education program would produce the desired change in knowledge, attitudes, and behavioral intentions.^ The quasi-experimental design of the study was untreated control group with pretest and posttest and untreated control group with posttest only. Female members of Mount Ararat Baptist Church took part in an eight-week, cancer education program based on social cognitive theory. Baseline data were collected before the start of the program at Mount Ararat and at Solid Rock Baptist Church, control group one. At the end of the program, the follow-up survey was administered at the program church, control church one, and in a third church, Damascus Missionary Baptist Church, which served as the posttest only group. The data were analyzed by Fisher's exact and paired t-test to determine if the program supported the project's hypotheses.^ Results of data analyses supported the major study hypotheses, the exception being behavioral intention to have Pap smear performed. Although the program appeared to have generally influenced changes in the desired direction, the results are limited due to the quasi-experimental design and small sample size. Longer term studies with larger sample sizes are needed to more fully develop and evaluate programs which impact the health of African-Americans. ^

NOVEL PHANTOMS AND POST-PROCESSING FOR DIFFUSION SPECTRUM IMAGING

High Angular Resolution Diffusion Imaging (HARDI) techniques, including Diffusion Spectrum Imaging (DSI), have been proposed to resolve crossing and other complex fiber architecture in the human brain white matter. In these methods, directional information of diffusion is inferred from the peaks in the orientation distribution function (ODF). Extensive studies using histology on macaque brain, cat cerebellum, rat hippocampus and optic tracts, and bovine tongue are qualitatively in agreement with the DSI-derived ODFs and tractography. However, there are only two studies in the literature which validated the DSI results using physical phantoms and both these studies were not performed on a clinical MRI scanner. Also, the limited studies which optimized DSI in a clinical setting, did not involve a comparison against physical phantoms. Finally, there is lack of consensus on the necessary pre- and post-processing steps in DSI; and ground truth diffusion fiber phantoms are not yet standardized. Therefore, the aims of this dissertation were to design and construct novel diffusion phantoms, employ post-processing techniques in order to systematically validate and optimize (DSI)-derived fiber ODFs in the crossing regions on a clinical 3T MR scanner, and develop user-friendly software for DSI data reconstruction and analysis. Phantoms with a fixed crossing fiber configuration of two crossing fibers at 90° and 45° respectively along with a phantom with three crossing fibers at 60°, using novel hollow plastic capillaries and novel placeholders, were constructed. T2-weighted MRI results on these phantoms demonstrated high SNR, homogeneous signal, and absence of air bubbles. Also, a technique to deconvolve the response function of an individual peak from the overall ODF was implemented, in addition to other DSI post-processing steps. This technique greatly improved the angular resolution of the otherwise unresolvable peaks in a crossing fiber ODF. The effects of DSI acquisition parameters and SNR on the resultant angular accuracy of DSI on the clinical scanner were studied and quantified using the developed phantoms. With a high angular direction sampling and reasonable levels of SNR, quantification of a crossing region in the 90°, 45° and 60° phantoms resulted in a successful detection of angular information with mean ± SD of 86.93°±2.65°, 44.61°±1.6° and 60.03°±2.21° respectively, while simultaneously enhancing the ODFs in regions containing single fibers. For the applicability of these validated methodologies in DSI, improvement in ODFs and fiber tracking from known crossing fiber regions in normal human subjects were demonstrated; and an in-house software package in MATLAB which streamlines the data reconstruction and post-processing for DSI, with easy to use graphical user interface was developed. In conclusion, the phantoms developed in this dissertation offer a means of providing ground truth for validation of reconstruction and tractography algorithms of various diffusion models (including DSI). Also, the deconvolution methodology (when applied as an additional DSI post-processing step) significantly improved the angular accuracy of the ODFs obtained from DSI, and should be applicable to ODFs obtained from the other high angular resolution diffusion imaging techniques.

The impact of a cooking and gardening summer camp experience on the fruit and vegetable consumption of elementary school-aged children

Childhood obesity is a significant public health problem. Over 15 percent of children in the United States are obese, and about 25 percent of children in Texas are overweight (CDC NHANES). Furthermore, about 30 percent of elementary school aged children in Harris County, Texas are overweight or obese (Children at Risk Institute 2010). In addition to actions such as increasing physical activity, decreasing television watching and video game time, decreasing snacking on low nutrient calorie dense foods and sugar sweetened beverages, children need to consume more fruits and vegetables. According to the National Health and Nutrition Examination Survey (NHANES) from 2002, about 26 percent of U.S. children are meeting the recommendations for daily fruit intake and about 16 percent are meeting the recommendations for daily vegetable intake (CDC NHANES). In 2004, the average total intake of vegetables was 0.9 cups per day and 1.1 cups of fruit per day by children ages four to nine years old in the U.S. (CDC NHANES). Not only do children need effective nutrition education to learn about fruits and vegetables, they also need access and repeated exposure to fruits and vegetables (Anderson 2009, Briefel 2009). Nutrition education interventions that provide a structured, hands-on curriculum such as school gardens have produced significant changes in child fruit and vegetable intake (Blair 2009, McAleese 2007). To prevent childhood obesity from continuing into adolescence and adulthood, effective nutrition education interventions need to be implemented immediately and for the long-term. However, research has shown short-term nutrition education interventions such as summer camps to be effective for significant changes in child fruit and vegetable intake, preferences, and knowledge (Heim 2009). ^ A four week summer camp based on cooking and gardening was implemented at 6 Multi-Service centers in a large, urban city. The participants included children ranging in age from 7 to 14 years old (n=64). The purpose of the camp was to introduce children to their food from the seed to the plate through the utilization of gardening and culinary exercises. The summer camp activities were aimed at increasing the children's exposure, willingness to try, preferences, knowledge, and intake of fruits and vegetables. A survey was given on the first day of camp and again on the last day of camp that measured the pre- and post differences in knowledge, intake, willingness to try, and preferences of fruits and vegetables. The present study examined the short-term effectiveness of a cooking and garden-based nutrition education program on the knowledge, willingness, preferences, and intake among children aged 8 to 13 years old (n=40). The final sample of participants (n=40) was controlled for those who completed pre- and post-test surveys and who were in or above the third grade level. Results showed a statistically significant increase in the reported intake of vegetables and preferences for vegetables, specifically green beans, and fruits. There was also a significant increase in preferences for fruits among boys and participants ages 11 to 13 years. The results showed a change in the expected direction of willingness to try, preferences for vegetables, and intake of fruit, however these were not statistically significant. Interestingly, the results also showed a decrease in the intake of low nutrient calorie dense foods such as sweets and candy.^

Cataract surgery in cancer patients and its impact on quality of life as measured by the National Eye Institute Visual Functioning Questionnaire - 25 (NEI-VFQ-25)

Purpose. The measurement of quality of life has become an important topic in healthcare and in the allocation of limited healthcare resources. Improving the quality of life (QOL) in cancer patients is paramount. Cataract removal and lens implantation appears to improve patient well-being of cancer patients, though a formal measurement has never been published in the US literature. In this current study, National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25), a validated vision quality of life metric, was used to study the change in vision-related quality of life in cancer patients who underwent cataract extraction with intraocular lens implantation. ^ Methods. Under an IRB approved protocol, cancer patients who underwent cataract surgery with intraocular lens implantation (by a single surgeon) from December 2008 to March 2011, and who had completed a pre- and postoperative NEI-VFQ-25 were retrospectively reviewed. Post-operative data was collected at their routine 4-6 week post-op visit. Patients' demographics, cancer history, their pre and postoperative ocular examinations, visual acuities, and NEI-VFQ-25 with twelve components were included in the evaluation. The responses were evaluated using the Student t test, Spearman correlation and Wilcoxon signed rank test. ^ Results. 63 cases of cataract surgery (from 54 patients) from the MD Anderson Cancer Center were included in the study. Cancer patients had a significant improvement in the visual acuity (P<0.0001) postoperatively, along with a significant increase in vision-related quality of life (P<0.0001). Patients also had a statistically significant improvement in ten of the twelve subcategories which are addressed in the NEI-VFQ-25. ^ Conclusions. In our study, cataract extraction and intraocular implantation showed a significant impact on the vision-related quality of life in cancer patients. Although this study includes a small sample size, it serves as a positive pilot study to evaluate and quantify the impact of a surgical intervention on QOL in cancer patients and may help to design a larger study to measure vision related QOL per dollar spent for health care cost in cancer patients.^