Stages of change and carotene intake in the Paso del Norte region: Que Sabrosa Vida

Understanding a population's dietary behavior is important to promote behaviors which have the most beneficial impact on health. The most recent Dietary Guidelines for Americans (2005) identifies carotenoids as a key nutrient to be consumed through increased intake of fruits and vegetables (FV). While some studies have included or focused on the Hispanic population, few have focused only on Mexican-American populations and staged its intake of FV. Stage of change behavior theory has been used to understand the adoption and promotion of healthy behaviors such as increased intake of FV. It has been shown to effectively aid interventionists' understanding of dietary behavior. Intake patterns of FV of older women, rural residents, and adolescents of Mexican American descent have been conducted but not by stages of change. This study aimed to determine the relationship between stages of change for fruits and vegetables (SOC-FV) and total carotene intake to assess the quality of SOC-FV as a surrogate measure of total carotene. ^ Data from the 2000 Qué Sabrosa Vida Community Nutrition Survey (QSV-CNS) were analyzed to identify the SOC-FV and sources of carotenes in a Mexican American population 18-60 yrs. of the Paso del Norte region. A 107 item interviewer administered food frequency questionnaire (FFQ) specifically calibrated for a Mexican American population was used to collect usual intake of total carotene. The QSV survey study population included 963 participants, 590 (61.3%) women and 373 (38.7%) men. A statistically significant mean difference in caloric intake between men and women was found (p-value = <0.01). When total carotene intake was adjusted for energy, there were significant differences between men and women (p-value = <0.0001) with women consuming a higher amount of total carotene (406 RE/kcal 1,000) than men (332 RE/kcal 1000). The food sources of total carotene for both genders included many items found in a traditional Mexican American diet. Chile, after carrots, was the highest contributor of dietary carotene. Total carotene intake was not associated with stages of change among women or men and their distributions were not linear. Mean differences of total carotene by stages of change were significant for women for pre-contemplation/contemplation (p-value = 0.04) and preparation (p-value = 0.0004) but not for men. ^ SOC-FV may serve as a surrogate measure for dietary carotene intake. This study's Mexican American population had a high carotene quality diet derived from traditional food items irrespective of their stage of change for fruits and vegetables. To better understand this population's dietary intake a measure for acculturation should be included. Interventions aimed at Mexican American populations should aim to promote traditional diets consistent with cultural practices.^ ^

A descriptive analysis of the consumers at farm stands outside WIC clinics

Because fruit and vegetable intake remains low in low-income populations, the attention of public health researchers has focused on different strategies to reach this population. One possible method of reaching low income populations is through government food assistance programs like the WIC's Farmers Market Nutrition Program (FMNP). This program provides vouchers to WIC recipients that are redeemable only at farmers' markets. In the summer of 2010, two farm stands near WIC clinics in Austin were surveyed in order to establish socio-demographic characteristics of the clientele of the markets. The overall purpose of this pilot study was to describe the clientele of the markets and to examine associations between food insecurity, acculturation, socio-demographic factors, and farmers' market participants' fruit and vegetable intake. The sample was a convenience sample of farmers' market customers. One hundred study participants completed self-administered surveys. Independent t-tests were used to explore the differences in means of fruit and vegetable intake according to acculturation and food insecurity levels. The overall mean (SD) of daily fruit and vegetable intake was 4.20±2.69 for customers of both markets. Significant differences were reported between the two markets in overall fruit and vegetable intake and specifically in the following: 100% juice (P=.023), fruit consumption (P=.028), green salad (P=.003), and salsa (P=.044). The differences showed that customers at the market in a more busy location were on average reporting eating more fruits and vegetables than customers at another market that was located in a more secluded location. When examined by level of food security, individuals who were more food secure consumed more fruit (P=.016). When examined by level of acculturation, the overall fruit and vegetable intake was not significantly different between levels of acculturation. The overall findings in this report suggest that the population at these markets consists of individuals who are food insecure and on government assistance programs. While there were no significant differences between fruit and vegetable intake, acculturation and food insecurity, this report suggests the need for culturally tailored interventions that serve the Hispanic population and would assist this population to become more food secure.^

Effects of a health advocacy program to promote physical activity and nutrition behaviors among adolescents: An evaluation of the Young Leaders for Healthy Change program

Background. This study was designed to evaluate the effects of the Young Leaders for Healthy Change program, an internet-delivered program in the school setting that emphasized health advocacy skills-development, on nutrition and physical activity behaviors among older adolescents (13–18 years). The program consisted of online curricular modules, training modules, social media, peer and parental support, and a community service project. Module content was developed based on Social Cognitive Theory and known determinants of behavior for older adolescents. ^ Methods. Of the 283 students who participated in the fall 2011 YL program, 38 students participated in at least ten of the 12 weeks and were eligible for this study. This study used a single group-only pretest/posttest evaluation design. Participants were 68% female, 58% white/Caucasian, 74% 10th or 11th graders, and 89% mostly A and/or B students. The primary behavioral outcomes for this analysis were participation in 60-minutes of physical activity per day, 20-minutes of vigorous- or moderate- intensity physical activity (MVPA) participation per day, television and computer time, fruit and vegetable (FV) intake, sugar-sweetened beverage intake, and consumption of breakfast, home-cooked meals, and fast food. Other outcomes included knowledge, beliefs, and attitudes related to healthy eating, physical activity, and advocacy skills. ^ Findings. Among the 38 participants, no significant changes in any variables were observed. However, among those who did not previously meet behavioral goals there was an 89% increase in students who participated in more than 20 minutes of MVPA per day and a 58% increase in students who ate home-cooked meals 5–7 days per week. The majority of participants met program goals related to knowledge, beliefs, and attitudes prior to the start of the program. Participants reported either maintaining or improving to the goal at posttest for all items except FV intake knowledge, taste and affordability of healthy foods, interest in teaching others about being healthy, and ease of finding ways to advocate in the community. ^ Conclusions. The results of this evaluation indicated that promoting healthy behaviors requires different strategies than maintaining healthy behaviors among high school students. In the school setting, programs need to target the promotion and maintenance of health behaviors to engage all students who participate in the program as part of a class or club activity. Tailoring the program using screening and modifying strategies to meet the needs of all students may increase the potential reach of the program. The Transtheoretical Model may provide information on how to develop a tailored program. Additional research on how to utilize the constructs of TTM effectively among high school students needs to be conducted. Further evaluation studies should employ a more expansive evaluation to assess the long-term effectiveness of health advocacy programming.^

The role of youth sports in public health

Study 1: Schools provide a range of opportunities for youth to be active, however, over the past decade, these opportunities have been declining. Sports teams are a promising venue to promote physical activity yet limited research has examined the gender an ethnic differences in sport participation. The purpose of this study is to examine trends in sport participation from 1991-2009 among US high school students. Secondly, we examined the association between gender and ethnicity with sports over time. This serial cross-sectional study used surveillance data from the Youth Risk Behavior Survey, a probability based sample weighted to represent gender and race/ethnic subpopulations of US high school students. The findings of this paper reveal persistent gender and ethnic disparities for sports participation among US youth. Since sports teams may provide a substantial source of physical activity, greater efforts should be undertaken to increase the participation of girls, especially minorities, in sports teams. ^ Study 2: Sports team participation is congruent with teaching and supporting healthy eating, yet limited research has examined the association between sports participation and dietary behaviors. This study aims to determine the association between youth sports participation and dietary behaviors among elementary-aged children. Significant dose-response associations were observed between number of sports teams and consumption of most fruits and vegetables. The likelihood of eating fruit for boys increased with the number of sports teams (1 team: OR=1.89; 3 teams: OR=3.44, p<0.001) and the likelihood of consuming green vegetables for girls was higher with the number of sports teams (1 team: OR=1.50; 3 teams: OR=2.39; p<0.001). For boys, the odds of consuming fruit-flavored drinks was higher ( p=0.019) and the odds of drinking soda was lower (p=0.018) with participation in increasing number of sports teams whereas for girls, sports participation was positively associated with diet soda consumption (p=0.006). ^ Study 3: Parents and peers have been shown to have a strong influence over the physical activity, dietary, and sedentary behaviors of youth. Youth sports teams have the potential to offer physical activity, displace sedentary behaviors, and promote a healthy diet. The purpose of this study is to assess how peer and parental support for physical activity and healthy eating, coupled with sport participation, is associated obesity related risk factors including diet and sedentary behaviors. A secondary analysis of data from the School Physical Activity and Nutrition study, a state-representative survey, was conducted. Eighth (n=3,931) and 11th (n=2,785) grade students were categorized into four groups based upon the level of peer and parental support derived from a three item scale and their participation in sports (sports/high support, sports/low support, no sports/high support, no sports/low support). Linear models were conducted to determine the difference in means between these groups for the following outcome variables: previous day fruit and vegetable intake, scores for an unhealthy and healthy food index, and hours spent watching television, playing video games, and working on a computer. Eighth graders had significantly greater levels of parental support for healthy eating and physical activity compared to 11th grade. Both 8 th and 11th graders in the sport/high support for healthy eating from peers and parents scored significantly higher on the healthy food index than other groups. Eighth and 11th graders in the sport/high support for physical activity from peers participated in fewer hours of sedentary behaviors than any other group (p ≤ 0.032). Although it is thought that sport participation may offer opportunities to support a healthy diet and displace sedentary time by offering providing physical activity, our study found that parental and peer support for activity and healthy eating may further attenuate this association. Parents and peer support should be an important target when developing strategies to improve healthy diets and reduce sedentary time among youth, especially in the context of youth sports. (Abstract shortened by UMI.)^

Structural conservations and diversities of dsRNA viruses: Structural studies of the cytoplasmic polyhedrosis virus by electron cryomicroscopy and 3D reconstruction

The Reoviridae virus family is a group of economically and pathologically important viruses that have either single-, double-, or triple-shelled protein layers enclosing a segmented double stranded RNA genome. Each virus particle in this family has its own viral RNA dependent RNA polymerase and the enzymatic activities necessary for the mature RNA synthesis. Based on the structure of the inner most cores of the viruses, the Reoviridae viruses can be divided into two major groups. One group of viruses has a smooth surfaced inner core, surrounded by complete outer shells of one or two protein layers. The other group has an inner core decorated with turrets on the five-fold vertices, and could either completely lack or have incomplete outer protein layers. The structural difference is one of the determinant factors for their biological differences during the infection. ^ Cytoplasmic polyhedrosis virus (CPV) is a single-shelled, turreted virus and the structurally simplest member in Reoviridae. It causes specific chronic infections in the insect gut epithelial cells. Due to its wide range of insect hosts, CPV has been engineered as a potential insecticide for use in fruit and vegetable farming. Its unique structural simplicity, unparalleled capsid stability and ease of purification make CPV an ideal model system for studying the structural basis of dsRNA virus assembly at the highest possible resolution by electron cryomicroscopy (cryoEM) and three-dimensional (3D) reconstruction. ^ In this thesis work, I determined the first 3D structure of CPV capsids using 100 kV cryoEM. At an effective resolution of 17 Å, the full capsid reveals a 600-Å diameter, T = 1 icosahedral shell decorated with A and B spikes at the 5-fold vertices. The internal space of the empty CPV is unoccupied except for 12 mushroom-shaped densities that are attributed to the transcriptional enzyme complexes. The inside of the full capsid is packed with icosahedrally-ordered viral genomic RNA. The interactions of viral RNA with the transcriptional enzyme complexes and other capsid proteins suggest a mechanism for RNA transcription and subsequent release. ^ Second, the interactions between the turret proteins (TPs) and the major capsid shell protein (CSPs) have been identified through 3D structural comparisons of the intact CPV capsids with the spikeless CPV capsids, which were generated by chemical treatments. The differential effects of these chemical treatment experiments also indicated that CPV has a significantly stronger structural integrity than other dsRNA viruses, such as the orthoreovirus subcores, which are normally enclosed within outer protein shells. ^ Finally, we have reconstructed the intact CPV to an unprecendented 8 Å resolution from several thousand of 400kV cryoEM images. The 8 Å structure reveals interactions among the 120 molecules of each of the capsid shell protein (CSP), the large protrusion protein (LPP), and 60 molecules of the turret protein (TP). A total of 1980 α-helices and 720 β-sheets have been identified in these capsid proteins. The CSP structure is largely conserved, with the majority of the secondary structures homologous to those observed in the x-ray structures of corresponding proteins of other reoviruses, such as orthoreovirus and bluetongue virus. The three domains of TP are well positioned to play multifunctional roles during viral transcription. The completely non-equivalent interactions between LPP and CSP and those between the anchoring domain of TP and CSP account for the unparalleled stability of this structurally simplest member of the Reoviridae. ^

Tecnologías de conservación por métodos combinados en pimiento, chaucha y berenjena

La tecnología de los métodos combinados permite reducir la intensidad del tratamiento térmico y mantener las propiedades organolépticas en el producto final, mediante una combinación de obstáculos que aseguran la estabilidad y seguridad microbiana. El objetivo de este trabajo fue aplicar dicha tecnología en la conservación de tres hortalizas: pimiento, chaucha y berenjena y analizar la calidad y vida útil de los productos obtenidos. La elaboración de las conservas se efectuó del siguiente modo: las hortalizas fueron cortadas y posteriormente escaldadas en solución de ácidos cítrico, láctico y acético. Terminada esta etapa se envasaron con la solución de relleno, constituida por los ácidos de la solución de escaldado con la adición de ácido ascórbico. Los análisis que se realizaron tanto en el material fresco como en los productos procesados fueron: humedad, pH, hidratos de carbono, lípidos, proteína, vitamina C, °Brix, actividad enzimática y acidez total. En los productos ya procesados se realizó el control microbiológico. Los resultados indican que la aplicación de los métodos combinados permite conservar los productos elaborados a temperatura ambiente y se mantiene su seguridad microbiológica.

Impact testing in melon (Cucumis melo L.)

The application of Rheology to study biological systems is a new and very extensive matter, in which melon is absolutely unknown. The goal of this work is to determine some physical characteristics of this fruit, immediately after harvest and during its conservation in cold storage. Portugal and Spain are the most interested countries in these studies, as they are important producers of melon. The varieties Branco da Leziria and Piel de sapo were chosen because they are the most popular in both countries. The fruit were studied on the day they were harvested, and then were conserved in cold storage in the "Instituto del Frio" in Madrid, and they were periodically tested again. Thus during seven days the same fruits, and new fruits, were picked up and tested. On the first day of testing we had 20 fruits to study and at the end of the testing period we had used 80 fruits. The results from the non-destructive impact test were very significant and they may contribute to standardise methods to measure fruit maturity. These results were confirmed by those obtained from compression tests. The results obtained during the Impact tests with melon were similar to those obtained previously with other fruits. There is a close relationship between the results of the Impact tests and Compression tests. Tests like Impact and Compression can be adapted to melon, varieties 'Piel de Sapo" and 'Branco de Leziria', allowing us to continue further work with this species. The great number of data obtained during performance of the tests allowed us to go on with this work and to contribute to standardise methods of measurement and expression of characteristics of a new biological product. During the "Impact damage in fruits and vegetables" workshop, held in Zaragoza in 1990, these matters were included in the priority list.

Impact damage on selected varieties of apples, pears and other fruits.

During the past years, different laboratory impact response studies have been carrj.ec out in following fruits: apples (2 varieties), pears (4 varieties), Asian or Nashi pears (4 varieties), melons (2 varieties), peaches (2 varieties) and avocados. The methodology of the tests is described, as well as the results and observations obtained in each group of tests. Impact response is compared to bruising susceptibility, bruise characteristics (appearance and structural features) and varietal and ripeness differences.

Effect of impacting mass on firmness sensing of fruits.

There has been an increased interest in using impact techniques for sensing firmness of fruits and vegetables. When an impacter is used to impact a fruit, the impacting mass is an important parameter which affects both the impact signal and fruit damage. Results of theoretical analysis and tests conducted on two varieties of pears indicate that lowering the impacting mass results in amplifying the measured signal, reducing sensing errors, and minimizing damage to the fruit.

Non-destructive optical characterization of fruits in the red and near infrared.

Increasing attention is being paid to the possible development of non-invasive tests for the assessment of the quality of Fruits. We propose a novel non-destructive method for the measurement of the internal optical properties of fruits and vegetables by means of lime-resolved reflectance spectroscopy in the visible and NIR range. A Fully automated instrumentation for time-resolved reflectance measurements was developed. It is based on mode-locked laser sources and electronics for time-correlated single photon counting, and provides a time-resolution of 120-160 ps. The system was used to probe the optical properties of several species and varieties of Fruits and vegetables in the red and NIR range (650-1000 nm). In most Fruits, the absorption line shape is dominated by the absorption peak of water, centred around 970 nm. Generally, the absorption spectra also show the spectral features typical of chlorophyll, with maximum at 675 nm. In particular, for what concerns apples, variations in peak intensity are observed depending on the variety, the degree of ripeness as well as the position on the apple. For all the species and varieties considered, the transport scattering coefficient decreases progressively upon increasing the wavelength.

An alternative pathway to β-carotene formation in plant chromoplasts discovered by map-based cloning of Beta and old-gold color mutations in tomato

Carotenoid pigments in plants fulfill indispensable functions in photosynthesis. Carotenoids that accumulate as secondary metabolites in chromoplasts provide distinct coloration to flowers and fruits. In this work we investigated the genetic mechanisms that regulate accumulation of carotenoids as secondary metabolites during ripening of tomato fruits. We analyzed two mutations that affect fruit pigmentation in tomato (Lycopersicon esculentum): Beta (B), a single dominant gene that increases β-carotene in the fruit, and old-gold (og), a recessive mutation that abolishes β-carotene and increases lycopene. Using a map-based cloning approach we cloned the genes B and og. Molecular analysis revealed that B encodes a novel type of lycopene β-cyclase, an enzyme that converts lycopene to β-carotene. The amino acid sequence of B is similar to capsanthin-capsorubin synthase, an enzyme that produces red xanthophylls in fruits of pepper (Capsicum annum). Our results prove that β-carotene is synthesized de novo during tomato fruit development by the B lycopene cyclase. In wild-type tomatoes B is expressed at low levels during the breaker stage of ripening, whereas in the Beta mutant its transcription is dramatically increased. Null mutations in the gene B are responsible for the phenotype in og, indicating that og is an allele of B. These results confirm that developmentally regulated transcription is the major mechanism that governs lycopene accumulation in ripening fruits. The cloned B genes can be used in various genetic manipulations toward altering pigmentation and enhancing nutritional value of plant foods.

Characterization of Two Divergent Endo-β-1,4-Glucanase cDNA Clones Highly Expressed in the Nonclimacteric Strawberry Fruit

Two cDNAs clones (Cel1 and Cel2) encoding divergent endo-β-1,4-glucanases (EGases) have been isolated from a cDNA library obtained from ripe strawberry (Fragaria x ananassa Duch) fruit. The analysis of the amino acid sequence suggests that Cel1 and Cel2 EGases have different secondary and tertiary structures and that they differ in the presence of potential N-glycosylation sites. By in vitro translation we show that Cel1 and Cel2 bear a functional signal peptide, the cleavage of which yields mature proteins of 52 and 60 kD, respectively. Phylogenetic analysis revealed that the Cel2 EGase diverged early in evolution from other plant EGases. Northern analysis showed that both EGases are highly expressed in fruit and that they have different temporal patterns of accumulation. The Cel2 EGase was expressed in green fruit, accumulating as the fruit turned from green to white and remaining at an elevated, constant level throughout fruit ripening. In contrast, the Cel1 transcript was not detected in green fruit and only a low level of expression was observed in white fruit. The level of Cel1 mRNA increased gradually during ripening, reaching a maximum in fully ripe fruit. The high levels of Cel1 and Cel2 mRNA in ripe fruit and their overlapping patterns of expression suggest that these EGases play an important role in softening during ripening. In addition, the early expression of Cel2 in green fruit, well before significant softening begins, suggests that the product of this gene may also be involved in processes other than fruit softening, e.g. cell wall expansion.

A Novel Alkaline α-Galactosidase from Melon Fruit with a Substrate Preference for Raffinose1

The cucurbits translocate the galactosyl-sucrose oligosaccharides raffinose and stachyose, therefore, α-galactosidase (α-d-galactoside galactohydrolase, EC 3.2.1.22) is expected to function as the initial enzyme of photoassimilate catabolism. However, the previously described alkaline α-galactosidase is specific for the tetrasaccharide stachyose, leaving raffinose catabolism in these tissues as an enigma. In this paper we report the partial purification and characterization of three α-galactosidases, including a novel alkaline α-galactosidase (form I) from melon (Cucumis melo) fruit tissue. The form I enzyme showed preferred activity with raffinose and significant activity with stachyose. Other unique characteristics of this enzyme, such as weak product inhibition by galactose (in contrast to the other α-galactosidases, which show stronger product inhibition), also impart physiological significance. Using raffinose and stachyose as substrates in the assays, the activities of the three α-galactosidases (alkaline form I, alkaline form II, and the acid form) were measured at different stages of fruit development. The form I enzyme activity increased during the early stages of ovary development and fruit set, in contrast to the other α-galactosidase enzymes, both of which declined in activity during this period. In the mature, sucrose-accumulating mesocarp, the alkaline form I enzyme was the major α-galactosidase present. We also observed hydrolysis of raffinose at alkaline conditions in enzyme extracts from other cucurbit sink tissues, as well as from young Coleus blumei leaves. Our results suggest different physiological roles for the α-galactosidase forms in the developing cucurbit fruit, and show that the newly discovered enzyme plays a physiologically significant role in photoassimilate partitioning in cucurbit sink tissue.

Polygalacturonase Gene Expression in Ripe Melon Fruit Supports a Role for Polygalacturonase in Ripening-Associated Pectin Disassembly

Ripening-associated pectin disassembly in melon is characterized by a decrease in molecular mass and an increase in the solubilization of polyuronide, modifications that in other fruit have been attributed to the activity of polygalacturonase (PG). Although it has been reported that PG activity is absent during melon fruit ripening, a mechanism for PG-independent pectin disassembly has not been positively identified. Here we provide evidence that pectin disassembly in melon (Cucumis melo) may be PG mediated. Three melon cDNA clones with significant homology to other cloned PGs were isolated from the rapidly ripening cultivar Charentais (C. melo cv Reticulatus F1 Alpha) and were expressed at high levels during fruit ripening. The expression pattern correlated temporally with an increase in pectin-degrading activity and a decrease in the molecular mass of cell wall pectins, suggesting that these genes encode functional PGs. MPG1 and MPG2 were closely related to peach fruit and tomato abscission zone PGs, and MPG3 was closely related to tomato fruit PG. MPG1, the most abundant melon PG mRNA, was expressed in Aspergillus oryzae. The culture filtrate exponentially decreased the viscosity of a pectin solution and catalyzed the linear release of reducing groups, suggesting that MPG1 encodes an endo-PG with the potential to depolymerize melon fruit cell wall pectin. Because MPG1 belongs to a group of PGs divergent from the well-characterized tomato fruit PG, this supports the involvement of a second class of PGs in fruit ripening-associated pectin disassembly.