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1.  Formative research methods for designing culturally appropriate, integrated child nutrition and development interventions: An overview 
Nutritional and developmental insults in the first few years of life have profound public health implications, including substantial contributions to neonatal, infant, and early childhood morbidity and mortality, as well as longer term impacts on cognitive development, school achievement, and worker productivity. Optimal development that can lead to the attainment of the individual's fullest potential therefore requires a combination of genetic capacity, adequate nutrition, psychosocial stimulation, and safe, clean physical environments. Researchers and policymakers have called for integrated child nutrition and development interventions for more than twenty years, yet there are only a handful of efficacy trials and even fewer examples of integrated interventions that have been taken to scale. While a critical component to the design of such interventions is formative research, there is a dearth of information in both the literature and policy arenas to guide this phase of the process. To move the field forward, this paper first provides an overview of formative research methods with a focus on qualitative inquiry, a description of the critical domains to be assessed (infant and young child feeding, responsive feeding, and child development), and currently available resources. Application of these methods is provided through a real-world case study—the design of an integrated nutrition and child development efficacy trial in Andhra Pradesh, India. Recommendations for next steps are discussed, the most important of which is the need for a comprehensive set of formative guidelines for designing locally tailored, culturally appropriate integrated interventions.
PMCID: PMC4269231  PMID: 24673167
3.  Home-Schooled Children are thinner, leaner, and report better diets relative to traditionally-schooled children 
Obesity (Silver Spring, Md.)  2013;22(2):497-503.
To examine and compare the relationships among diet, physical activity, and adiposity between home-schooled children (HSC) and traditionally-schooled children (TSC).
Design and Methods
Subjects were HSC (n=47) and TSC (n=48) aged 7 to 12 years old. Dietary intakes were determined via two 24-hour recalls and physical activity was assessed with 7 days of accelerometry. Fat mass (FM), trunk fat, and percent body fat (%BF) were measured by dual-energy x-ray absorptiometry (DXA).
Relative to HSC, TSC demonstrated significantly higher BMI percentiles, FM, trunk fat, and %BF; consumed 120 total kilocalories more per day; and reported increased intakes of trans fats, total sugar, added sugars, calcium, and lower intakes of fiber, fruits, and vegetables (p<0.05). At lunch, TSC consumed significantly more calories, sugar, sodium, potassium, and calcium compared to HSC (p<0.05). Physical activity did not differ between groups. Traditional schooling was associated with increased consumption of trans fat, sugar, calcium (p<.05); lower intakes of fiber, and fruits and vegetables (p<.05); and higher FM, %BF, and trunk fat (p<0.01), after adjustment for covariates.
These data suggest HSC may consume diets that differ in energy and nutrient density relative to TSC, potentially contributing to differences in weight and adiposity.
PMCID: PMC3946420  PMID: 24039204
obesity; adiposity; youth; nutrition; physical activity; diet quality
4.  Using participant hedonic ratings of food images to construct data driven food groupings☆ 
Appetite  2014;79:189-196.
Theorists posit that food reward is a powerful determinant of intake, yet little is known regarding how individuals’ hedonic ratings of a variety of foods interrelate and how hedonic ratings correspond to habitual dietary intake. Participant ratings of food appeal of 104 food images were collected while participants were in a fed state (n = 129). Self-reported frequency of intake of the food items, perceived hunger, body mass index (BMI), and dietary restraint were also assessed. Principal components analysis (PCA) was employed to analyze hedonic ratings of the foods, to identify component structures and to reduce the number of variables. The resulting component structures comprised 63 images loading on seven components including Energy-Dense Main Courses, Light Main Courses and Seafood as well as components more analogous to traditional food groups (e.g., Fruits, Grains, Desserts, Meats). However, vegetables were not represented in a unique, independent component. All components were positively correlated with reported intake of the food items (r’s = .26–.52, p < .05), except for the Light Main Course component (r = .10). BMI showed a small positive relation with aggregated food appeal ratings (r = .19; p < .05), which was largely driven by the relations between BMI and appeal ratings for Energy-Dense Main Courses (r = .24; p < .01) and Desserts (r = .27; p < .01). Dietary restraint showed a small significant negative relation to Energy-Dense Main Courses (r = −.21; p < .05), and Meats (r = −.18; p < .05). The present investigation provides novel evidence that how individuals’ hedonic ratings of foods aggregate into food components and how these component ratings relate to dietary intake. The notable absence of a vegetable component suggests that individuals’ liking for vegetables is highly variable and, from an empirical standpoint, not related to how they respond hedonically to other food categories.
PMCID: PMC4104662  PMID: 24769294
Food and beverages; Food preferences; Vegetables; Obesity; Hedonic value
5.  Eating-related Behaviors and Appetite During Energy Imbalance in Obese-Prone and Obese-Resistant Individuals 
Appetite  2013;65:96-102.
While the majority of Americans are now overweight, some individuals maintain their weight with minimal effort. This study investigated behavioral differences between 58 individuals recruited as either obese-resistant (OR) or obese-prone (OP) based on self-identification, BMI, and personal/family weight history. Subjects were studied during Eucaloric (EU), Overfed (OF), and Underfed (UF) phases which included a run-in diet, 1 day intervention diet, and a study day. At baseline, subjects completed the Three Factor Eating Questionnaire (TFEQ) and Power of Food Scale (PFS). On the study day, ratings of appetite, food appeal and desire, and food cravings were performed in response to a breakfast shake. OF resulted in reduced hunger and food desire while UF resulted in increased hunger and food appeal and desire. While hunger did not differ between groups, OP had higher scores for TFEQ measures (hunger, restraint and disinhibition), higher “hedonic hunger” as measured by the PFS, and greater food cravings and ratings of food appeal and desire. These results suggest that subjective hunger and desire for food change significantly after only one day of over- or underfeeding. Additionally, we found several behavioral differences between groups that are likely to promote weight gain over time in the OP.
PMCID: PMC3622833  PMID: 23402714
overfeeding; underfeeding; obesity prone; obesity resistant; hunger; satiety
6.  Development of the Responsiveness to Child Feeding Cues Scale 
Appetite  2013;65:210-219.
Parent-child feeding interactions during the first two years of life are thought to shape child appetite and obesity risk, but remain poorly studied. This research was designed to develop and assess the Responsiveness to Child Feeding Cues Scale (RCFCS), an observational measure of caregiver responsiveness to child feeding cues relevant to obesity. General responsiveness during feeding as well as maternal responsiveness to child hunger and fullness were rated during mid-morning feeding occasions by 3 trained coders using digitally-recordings. Initial inter-rater reliability and criterion validity were evaluated in a sample of 144 ethnically-diverse mothers of healthy 7- to 24-month-old children. Maternal self-report of demographics and measurements of maternal/child anthropometrics were obtained. Inter-rater agreement for most variables was excellent (ICC>0.80). Mothers tended to be more responsive to child hunger than fullness cues (p<0.001). Feeding responsiveness dimensions were associated with demographics, including maternal education, maternal body mass index, and child age, and aspects of feeding, including breastfeeding duration, and self-feeding. The RCFCS is a reliable observational measure of responsive feeding for children <2 years of age that is relevant to obesity in early development.
PMCID: PMC3995412  PMID: 23419965
Responsive feeding; Feeding cues; Hunger and fullness; Child appetite
7.  Intake of Selected Minerals and Risk of Premenstrual Syndrome 
American Journal of Epidemiology  2013;177(10):1118-1127.
Iron, potassium, zinc, and other minerals might impact the development of premenstrual syndrome (PMS) through multiple mechanisms, but few studies have evaluated these relations. We conducted a case-control study nested within the prospective Nurses' Health Study II (1991–2001). Participants were free from PMS at baseline. After 10 years, 1,057 women were confirmed as PMS cases and 1,968 as controls. Mineral intake was assessed using food frequency questionnaires completed in 1991, 1995, and 1999. After adjustment for calcium intake and other factors, women in the highest quintile of nonheme iron intake had a relative risk of PMS of 0.64 (95% confidence interval (CI): 0.44, 0.92; P for trend = 0.04) compared with women in the lowest quintile. Women in the highest quintile of potassium intake had a relative risk of 1.46 (95% CI: 0.99, 2.15; P for trend = 0.04) compared with women in the lowest quintile. High intake of zinc from supplements was marginally associated with PMS (for intake of ≥25 mg/day vs. none, relative risk = 0.69, 95% CI: 0.46, 1.02; P for trend = 0.05). Intakes of sodium, magnesium, and manganese were unrelated to PMS risk. These findings suggest that dietary minerals may be useful in preventing PMS. Additional studies are needed to confirm these relations.
PMCID: PMC3649635  PMID: 23444100
dietary iron; minerals; premenstrual syndrome
8.  Simplified derivatization for determining sphingolipid fatty acyl composition by gas chromatography–mass spectrometry 
Journal of chromatography  1992;605(2):281-286.
A simple procedure for simultaneously derivatizing non-hydroxy and hydroxy fatty acids prior to GC analysis [I. Ciucanu and F. Kerek, J. Chromatogr., 284 (1984) 179] has been evaluated for its usefulness in determining sphingolipid acyl composition. The method uses methyl iodide in polar aprotic solvents to generate methyl esters of carboxyl groups and methyl ethers of hydroxyl groups. Methylation efficiency is examined as a function of hydroxyl group presence and location in free fatty acids as well as a function of 2-hydroxy fatty acid chain length. Conditions are also reported for efficient saponification and derivatization of sphingolipid fatty acyl chains as is illustrated using bovine brain galactosylceramide.
PMCID: PMC4003555  PMID: 1500464
9.  Plasma 25-hydroxyvitamin D and risk of premenstrual syndrome in a prospective cohort study 
BMC Women's Health  2014;14:56.
Moderate to severe premenstrual syndrome (PMS) affects 8–20 percent of premenopausal women. Previous studies suggest that high dietary vitamin D intake may reduce risk. However, vitamin D status is influenced by both dietary vitamin D intake and sunlight exposure and the association of vitamin D status with PMS remains unclear.
We assessed the relation of plasma 25-hydroxyvitamin D (25OHD), total calcium and parathyroid hormone levels with risk of PMS and specific menstrual symptoms in a case–control study nested within the prospective Nurses’ Health Study II. Cases were 401 women free from PMS at baseline who developed PMS during follow-up (1991–2005). Controls were women not experiencing PMS (1991–2005), matched 1:1 with cases on age and other factors. Timed luteal phase blood samples were collected between 1996 and 1999 from cases and controls. We used conditional logistic regression to model the relation of 25OHD levels with risk of PMS and individual menstrual symptoms.
In analyses of all cases and controls, 25OHD levels were not associated with risk of PMS. However, results differed when the timing of blood collection vs. PMS diagnosis was considered. Among cases who had already been diagnosed with PMS at the time of blood collection (n = 279), 25OHD levels were positively associated with PMS, with each 10 nmol/L change in 25OHD associated with a 13% higher risk. Among cases who developed PMS after blood collection (n = 123), 25OHD levels were unrelated to risk of PMS overall, but inversely related to risk of specific menstrual symptoms. For example, each 10 nmol/L increase was associated with a significant 21% lower risk of breast tenderness (P = 0.02). Total calcium or parathyroid hormone levels were unrelated to PMS.
25OHD levels were not associated with overall risk of PMS. The positive association observed among women already experiencing PMS at the time of 25OHD measurement is likely due to confounding by indication related to use of dietary supplements to treat menstrual symptoms. Results from prospective analyses, which were less likely influenced by this bias, suggest that higher 25OHD levels may be inversely related to the development of specific menstrual symptoms.
PMCID: PMC3997197  PMID: 24725979
Vitamin D; Calcium; Premenstrual syndrome; Prospective studies
11.  Marine trophic diversity in an anadromous fish is linked to its life-history variation in fresh water 
Biology Letters  2013;9(1):20120824.
We used carbon and nitrogen stable isotopes from muscle tissues accrued in the ocean to examine whether marine foraging tactics in anadromous sockeye salmon (Oncorhynchus nerka) are linked to their ultimate freshwater life history as adults. Adults from large-bodied populations spawning in deep freshwater habitats had more enriched δ15N than individuals from small-bodied populations from shallow streams. Within populations, earlier maturing individuals had higher δ15N than older fish. These differences in δ15N suggest that the fish with different life histories or spawning habitats in freshwater either fed at different trophic positions or in different habitats in the ocean. We propose that, nested within interspecific diversity in the ecological attributes of salmon, population and life-history diversity in spawning adults is associated with variation in marine foraging tactics. These results further indicate that the trophic diversity of sockeye salmon in the ocean may be linked to trade-offs in ecological and evolutionary constraints they eventually experience as adults in freshwater ecosystems.
PMCID: PMC3565491  PMID: 23173190
stable isotopes; sockeye salmon; nitrogen; geomorphology
12.  Cluster-randomized trial on complementary and responsive feeding education to caregivers found improved dietary intake, growth, and development among rural Indian toddlers 
Maternal & child nutrition  2012;9(1):99-117.
Inadequate feeding and care may contribute to high rates of stunting and underweight among children in rural families in India. This cluster-randomized trial tested the hypothesis that teaching caregivers appropriate complementary feeding, and strategies for how to feed and play responsively through home-visits would increase children’s dietary intake, growth, and development compared to home-visit-complementary feeding education alone or routine care. Sixty villages in Andhra Pradesh were randomized into 3 groups1 of 20 villages with 200 mother-infant dyads in each group. The Control Group (CG), received routine Integrated Child Development Services (ICDS); the Complementary Feeding Group (CFG), received the ICDS plus the World Health Organization recommendations on breastfeeding and complementary foods; and the Responsive Complementary Feeding & Play Group (RCF&PG) received the same intervention as the CFG plus skills for responsive feeding and psychosocial stimulation. Both intervention groups received bi-weekly visits by trained village women. The groups did not differ at 3 months on socioeconomic status, maternal and child nutritional indices and maternal depression. After controlling for potential confounding factors using the mixed models approach, the twelve-month intervention to the CFG and RCF&PG significantly (p<0.05) increased median intakes of energy, protein, Vitamin-A, calcium (CFG), iron and zinc, reduced stunting (0.19, CI: 0.0–0.4) in the CFG (but not RCF&PG) and increased (p<0.01) Bayley Mental Development scores(Mean=3.1, CI: 0.8–5.3) in the RCF&PG (but not CFG) compared to CG. Community-based educational interventions can improve dietary intake, length (CFG), and mental development (RCF&PG) for children under two years in food-secure rural Indian families.
PMCID: PMC3434308  PMID: 22625182
feeding methods; responsive complementary feeding; toddler; growth and development
13.  The Colorado LEAP study: rationale and design of a study to assess the short term longitudinal effectiveness of a preschool nutrition and physical activity program 
BMC Public Health  2013;13:1146.
The preschool years are a critical window for obesity prevention efforts; representing a time when children establish healthy eating habits and physical activity patterns. Understanding the context in which these behaviors develop is critical to formulating a model to address childhood obesity. The Colorado LEAP Study, an intervention study designed to prevent early childhood obesity, utilizes a social ecological approach to explore individual, family and environmental factors and their relationship to child weight status over a 3 year timeframe.
The study is located in 5 rural Colorado preschool centers and elementary schools (2 treatment and 3 control). Treatment sites receive The Food Friends® nutrition (12 weeks) and physical activity (18 weeks) interventions during preschool. Observational measures assess 3 layers of the social ecological model including individual, family and organizational inputs. Children’s food preferences, food intake, gross motor skills, physical activity (pedometers/accelerometers), cognitive, physical and social self-competence and height/weight are collected. Parents provide information on feeding and activity practices, child’s diet, oral sensory characteristics, food neophobia, home food and activity environment, height/weight and physical activity (pedometers). School personnel complete a school environment and policy assessment. Measurements are conducted with 3 cohorts at 4 time points – baseline, post-intervention, 1- and 2-year follow-up.
The design of this study allows for longitudinal exploration of relationships among eating habits, physical activity patterns, and weight status within and across spheres of the social ecological model. These methods advance traditional study designs by allowing not only for interaction among spheres but predictively across time. Further, the recruitment strategy includes both boys and girls from ethnic minority populations in rural areas and will provide insights into obesity prevention effects on these at risk populations.
Trial registration NCT01937481.
PMCID: PMC3867674  PMID: 24321701
Obesity; Social ecological model; Preschool; Early childhood; Intervention; Longitudinal
14.  Soothing the Threatened Brain: Leveraging Contact Comfort with Emotionally Focused Therapy 
PLoS ONE  2013;8(11):e79314.
Social relationships are tightly linked to health and well-being. Recent work suggests that social relationships can even serve vital emotion regulation functions by minimizing threat-related neural activity. But relationship distress remains a significant public health problem in North America and elsewhere. A promising approach to helping couples both resolve relationship distress and nurture effective interpersonal functioning is Emotionally Focused Therapy for couples (EFT), a manualized, empirically supported therapy that is strongly focused on repairing adult attachment bonds. We sought to examine a neural index of social emotion regulation as a potential mediator of the effects of EFT. Specifically, we examined the effectiveness of EFT for modifying the social regulation of neural threat responding using an fMRI-based handholding procedure. Results suggest that EFT altered the brain's representation of threat cues in the presence of a romantic partner. EFT-related changes during stranger handholding were also observed, but stranger effects were dependent upon self-reported relationship quality. EFT also appeared to increase threat-related brain activity in regions associated with self-regulation during the no-handholding condition. These findings provide a critical window into the regulatory mechanisms of close relationships in general and EFT in particular.
PMCID: PMC3835900  PMID: 24278126
15.  Strategies for Recruitment and Retention of Families from Low-Income, Ethnic Minority Backgrounds in a Longitudinal Study of Caregiver Feeding and Child Weight 
Children from low-SES and ethnic minority backgrounds are at heightened risk for overweight, yet are underrepresented in the pediatric obesity literature.
The current paper describes strategies employed to minimize barriers to recruitment and retention of African-American families receiving WIC services in a longitudinal study examining caregiver feeding and child weight.
Seventy-six families enrolled in the study over 3.5 years, and 50% of the families completed the study.
Implications for Practice
Despite effortful planning, unanticipated barriers likely contributed to lengthy recruitment and a modest retention rate. Future research should incorporate lessons learned to modify and develop effective strategies for increasing engagement of low-SES and ethnic minority families in research.
PMCID: PMC3782992  PMID: 24078763
16.  Biological Determinants Linking Infant Weight Gain and Child Obesity: Current Knowledge and Future Directions12 
Advances in Nutrition  2012;3(5):675-686.
Childhood obesity rates have reached epidemic proportions. Excessive weight gain in infancy is associated with persistence of elevated weight status and later obesity. In this review, we make the case that weight gain in the first 6 mo is especially predictive of later obesity risk due to the metabolic programming that can occur early postpartum. The current state of knowledge regarding the biological determinants of excess infant weight gain is reviewed, with particular focus on infant feeding choice. Potential mechanisms by which different feeding approaches may program the metabolic profile of the infant, causing the link between early weight gain and later obesity are proposed. These mechanisms are likely highly complex and involve synergistic interactions between endocrine effects and factors that alter the inflammatory and oxidative stress status of the infant. Gaps in current knowledge are highlighted. These include a lack of data describing 1) what type of infant body fat distribution may impart risk and 2) how maternal metabolic dysfunction (obesity and/or diabetes) may affect milk composition and exert downstream effects on infant metabolism. Improved understanding and management of these early postnatal determinants of childhood obesity may have great impact on reducing its prevalence.
PMCID: PMC3648749  PMID: 22983846
17.  The Effects of Tibolone in Older Postmenopausal Women 
The New England journal of medicine  2008;359(7):697-708.
Tibolone has estrogenic, progestogenic, and androgenic effects. Although tibolone prevents bone loss, its effects on fractures, breast cancer, and cardiovascular disease are uncertain.
In this randomized study, we assigned 4538 women, who were between the ages of 60 and 85 years and had a bone mineral density T score of −2.5 or less at the hip or spine or a T score of −2.0 or less and radiologic evidence of a vertebral fracture, to receive once-daily tibolone (at a dose of 1.25 mg) or placebo. Annual spine radiographs were used to assess for vertebral fracture. Rates of cardiovascular events and breast cancer were adjudicated by expert panels.
During a median of 34 months of treatment, the tibolone group, as compared wit h the placebo group, had a decreased risk of vertebral fracture, with 70 cases versus 126 cases per 1000 person-years (relative hazard, 0.55; 95% confidence interval [CI], 0.41 to 0.74; P<0.001), and a decreased risk of nonvertebral fracture, with 122 cases versus 166 cases per 1000 person-years (relative hazard, 0.74; 95% CI, 0.58 to 0.93; P = 0.01). The tibolone group also had a decreased risk of invasive breast cancer (relative hazard, 0.32; 95% CI, 0.13 to 0.80; P = 0.02) and colon cancer (relative hazard, 0.31; 95% CI, 0.10 to 0.96; P=0.04). However, the tibolone group had an increased risk of stroke (relative hazard, 2.19; 95% CI, 1.14 to 4.23; P = 0.02), for which the study was stopped in February 2006 at the recommendation of the data and safety monitoring board. There were no significant differences in the risk of either coronary heart disease or venous thromboembolism between the two groups.
Tibolone reduced the risk of fracture and breast cancer and possibly colon cancer but increased the risk of stroke in older women with osteoporosis. (ClinicalTrials. gov number, NCT00519857.)
PMCID: PMC3684062  PMID: 18703472
18.  A prospective study for prevalence and/or development of transfusion-transmitted infections in multiply transfused thalassemia major patients 
To evaluate the rate of seropositivity to hepatitis B and C and Human Immunodeficiency Virus (HIV) infections among children with β-thalassemia major receiving multiple transfusions in Ahmedabad, India, compared with healthy controls.
Materials and Methods:
The study was performed during January 2007 to January 2009 on multi-transfused children suffering with β-thalassemia major registered in the Prathama Blood Centre, Ahmedabad; Jeevandeep hospital, Ahmedabad; and Red Cross Blood Centre, Ahmedabad, and investigated for the prevalence and development of transfusion-transmitted infections. Hepatitis B surface Antigen (HBsAg), anti-Hepatitis C Virus (HCV) Antibodies (Ab), and HIV Ab were checked using a fourth-generation Enzyme-Linked Immunosorbent Assay (ELISA). Positive tests were confirmed by western blots. Healthy blood donors were used for the control group.
Hepatitis B surface antigen, anti-HCV Ab, and HIV Ab were positive in one of 96 (1.04%; 95% Confidence Interval (CI) = 0.17–1.3), 24 of 96 (25%; 95% CI = 11.4–14.2), and one of 96 (1.04%; 95% CI = 0.12–1.3), respectively. The rate of anti-HCV Ab was significantly higher in multi-transfused children suffering with β-thalassemia major. In thalassemia patients, the rate of positive anti-HCV Ab was significantly higher than that for positive HBsAg (P<0.001) and HIV Ab (P<0.001).
It is concluded that HCV is the current major problem in multi-transfused children with thalassemia major and more careful pretransfusion screening of blood for anti-HCV must be introduced in blood centers.
PMCID: PMC3439754  PMID: 22988380
Hepatitis B; hepatitis C; Human immunodeficiency virus; β-thalassemia major; seroprevalence
19.  Sweetness and Food Preference123 
The Journal of Nutrition  2012;142(6):1142S-1148S.
Human desire for sweet taste spans all ages, races, and cultures. Throughout evolution, sweetness has had a role in human nutrition, helping to orient feeding behavior toward foods providing both energy and essential nutrients. Infants and young children in particular base many of their food choices on familiarity and sweet taste. The low cost and ready availability of energy-containing sweeteners in the food supply has led to concerns that the rising consumption of added sugars is the driving force behind the obesity epidemic. Low-calorie sweeteners are one option for maintaining sweet taste while reducing the energy content of children’s diets. However, their use has led to further concerns that dissociating sweetness from energy may disrupt the balance between taste response, appetite, and consumption patterns, especially during development. Further studies, preferably based on longitudinal cohorts, are needed to clarify the developmental trajectory of taste responses to low-calorie sweeteners and their potential impact on the diet quality of children and youth.
PMCID: PMC3738223  PMID: 22573785
20.  Sporophytic ovule tissues modulate the initiation and progression of apomixis in Hieracium 
Journal of Experimental Botany  2012;63(8):3229-3241.
Apomixis in Hieracium subgenus Pilosella initiates in ovules when sporophytic cells termed aposporous initial (AI) cells enlarge near sexual cells undergoing meiosis. AI cells displace the sexual structures and divide by mitosis to form unreduced embryo sac(s) without meiosis (apomeiosis) that initiate fertilization-independent embryo and endosperm development. In some Hieracium subgenus Pilosella species, these events are controlled by the dominant LOSS OF APOMEIOSIS (LOA) and LOSS OF PARTHENOGENESIS (LOP) loci. In H. praealtum and H. piloselloides, which both contain the same core LOA locus, the timing and frequency of AI cell formation is altered in derived mutants exhibiting abnormal funiculus growth and in transgenic plants expressing rolB which alters cellular sensitivity to auxin. The impact on apomictic and sexual reproduction was examined here when a chimeric RNAse gene was targeted to the funiculus and basal portions of the ovule, and also when polar auxin transport was inhibited during ovule development following N-1-naphthylphthalamic acid (NPA) application. Both treatments led to ovule deformity in the funiculus and distal parts of the ovule and LOA-dependent alterations in the timing, position, and frequency of AI cell formation. In the case of NPA treatment, this correlated with increased expression of DR5:GFP in the ovule, which marks the accumulation of the plant hormone auxin. Our results show that sporophytic information potentiated by funiculus growth and polar auxin transport influences ovule development, the initiation of apomixis, and the progression of embryo sac development in Hieracium. Signals associated with ovule pattern formation and auxin distribution or perception may influence the capacity of sporophytic ovule cells to respond to LOA.
PMCID: PMC3350933  PMID: 22378948
Apomixis; auxin; gametophyte; ovule; seed
21.  Development of replication-defective lymphocytic choriomeningitis virus vectors for the induction of potent CD8+ T cell immunity 
Nature medicine  2010;16(3):339-345.
Lymphocytic choriomeningitis virus (LCMV) exhibits natural tropism for dendritic cells and represents the prototypic infection that elicits protective CD8+ T cell (cytotoxic T lymphocyte (CTL)) immunity. Here we have harnessed the immunobiology of this arenavirus for vaccine delivery. By using producer cells constitutively synthesizing the viral glycoprotein (GP), it was possible to replace the gene encoding LCMV GP with vaccine antigens to create replication-defective vaccine vectors. These rLCMV vaccines elicited CTL responses that were equivalent to or greater than those elicited by recombinant adenovirus 5 or recombinant vaccinia virus in their magnitude and cytokine profiles, and they exhibited more effective protection in several models. In contrast to recombinant adenovirus 5, rLCMV failed to elicit vector-specific antibody immunity, which facilitated re-administration of the same vector for booster vaccination. In addition, rLCMV elicited T helper type 1 CD4+ T cell responses and protective neutralizing antibodies to vaccine antigens. These features, together with low seroprevalence in humans, suggest that rLCMV may show utility as a vaccine platform against infectious diseases and cancer.
PMCID: PMC3247638  PMID: 20139992
22.  Morphology and gonad development of normal soldiers and reproductive soldiers of the termite Zootermopsis nevadensis nevadensis (Isoptera, Archotermopsidae)  
ZooKeys  2011;15-30.
Reproductive or neotenic soldiers of the Archotermopsid Zootermopsis nevadensis nevadensis (Hagen) are compared to sterile soldiers and primary male reproductives. Several head capsule morphometrics correlate significantly with gonad size across all forms and both sexes of soldiers. The easily observed field character of ratio of mandible length to labrum length is a consistent and reliable feature of head capsule external morphology for predicting gonad development and reproductive potential of soldier forms regardless of age, sex, or live weight.
PMCID: PMC3264407  PMID: 22287888
evolution of soldier caste; reproductive soldier; neotenic soldier; Zootermopsis; morphometrics
23.  Adiposity and the Development of Premenstrual Syndrome 
Journal of Women's Health  2010;19(11):1955-1962.
Moderate to severe premenstrual syndrome (PMS) affects 8%–20% of premenopausal women and causes substantial levels of impairment, but few modifiable risk factors for PMS have been identified. Adiposity may impact risk through the complex interaction of hormonal and neurochemical factors, but it is not known if adiposity increases a woman's risk of developing PMS. We have addressed these issues in a prospective study nested within the Nurses' Health Study 2.
Participants were a subset of women aged 27–44 and free from PMS at baseline, including 1057 women who developed PMS over 10 years of follow-up and 1968 controls. Body mass index (BMI), weight change and weight cycling were assessed biennially via questionnaire.
We observed a strong linear relationship between BMI at baseline and risk of incident PMS, with each 1 kg/m2 increase in BMI associated with a significant 3% increase in PMS risk (95% confidence interval [CI] 1.01-1.05). After adjustment for age, smoking, physical activity, and other factors, women with BMI ≥27.5 kg/m2 at baseline had significantly higher risks of PMS than women with BMI <20 kg/m2 (ptrend = 0.003). A large weight change between age 18 and the year 1991 was significantly associated with PMS risk, whereas weight cycling during this period was not. BMI was positively associated with specific symptoms, including swelling of extremities, backache, and abdominal cramping (all p < 0.001).
Our findings suggest that maintaining a healthy body mass may be important for preventing the development of PMS. Additional studies are needed to assess whether losing weight would benefit overweight and obese women who currently experience PMS.
PMCID: PMC2971655  PMID: 20874240
24.  Assessing food appeal and desire to eat: the effects of portion size & energy density 
Visual presentation of food provides considerable information such as its potential for palatability and availability, both of which can impact eating behavior.
We investigated the subjective ratings for food appeal and desire to eat when exposed to food pictures in a fed sample (n = 129) using the computer paradigm ImageRate. Food appeal and desire to eat were analyzed for the effects of food group, portion size and energy density of the foods presented as well as by participant characteristics.
Food appeal ratings were significantly higher than those for desire to eat (57.9 ± 11.6 v. 44.7 ± 18.0; p < 0.05). Body mass index was positively correlated to desire to eat (r = 0.20; p < 0.05), but not food appeal. Food category analyses revealed that fruit was the highest rated food category for both appeal and desire, followed by discretionary foods. Additionally, overweight individuals reported higher ratings of desire to eat large portions of food compared to smaller portions (p < 0.001), although these effects were relatively small. Energy density of the foods was inversely correlated with ratings for both appeal and desire (r's = - 0.27; p's < 0.01).
Results support the hypothesis that individuals differentiate between food appeal and desire to eat foods when assessing these ratings using the same type of metric. Additionally, relations among food appeal and desire to eat ratings and body mass show overweight individuals could be more responsive to visual foods cues in a manner that contributes to obesity.
PMCID: PMC3204278  PMID: 21943082
liking; wanting; food appeal; desire to eat; intake; hedonic; obesity; portion size
25.  Child Care Provider Training and a Supportive Feeding Environment in Child Care Settings in 4 States, 2003 
Preventing Chronic Disease  2011;8(5):A113.
Strategies to prevent adult chronic diseases, including obesity, must start in childhood. Because many preschool-aged children spend mealtimes in child care facilities, staff should be taught supportive feeding practices for childhood obesity prevention. Higher obesity rates among low-income children suggest that centers providing care to these children require special attention. We compared self-reported feeding practices at child care centers serving low-income children on the basis of whether they received funding and support from the Child and Adult Care Food Program (CACFP), which suggests supportive feeding practices. We also assessed training factors that could account for differences among centers.
Eligible licensed child care centers (n = 1600) from California, Colorado, Idaho, and Nevada received surveys. Of the 568 responding centers, 203 enrolled low-income families and served meals. We analyzed the responses of 93 directors and 278 staff for CACFP-funded centers and 110 directors and 289 staff from nonfunded centers. Chi square analyses, pairwise comparisons, t tests, and multiple linear regressions were used to compare CACFP-funded and nonfunded centers.
Significant differences were noted in 10 of 26 feeding practices between CACFP-funded and nonfunded centers. In each case, CACFP-funded centers reported practices more consistent with a supportive feeding environment. Forty-one percent of the variance could be explained by training factors, including who was trained, the credentials of those providing training, and the type of training.
Our findings suggest that when trained by nutrition professionals, child care staff learn, adopt, and operationalize childhood obesity prevention feeding guidelines, thereby creating a supportive mealtime feeding environment.
PMCID: PMC3181186  PMID: 21843416

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