RESUMO
Ribonucleoside analog inhibitors (rNAI) target the hepatitis C virus (HCV) RNA-dependent RNA polymerase nonstructural protein 5B (NS5B) and cause RNA chain termination. Here, we expand our studies on ß-d-2'-C-methyl-2,6-diaminopurine-ribonucleotide (DAPN) phosphoramidate prodrug 1 (PD1) as a novel investigational inhibitor of HCV. DAPN-PD1 is metabolized intracellularly into two distinct bioactive nucleoside triphosphate (TP) analogs. The first metabolite, 2'-C-methyl-GTP, is a well-characterized inhibitor of NS5B polymerase, whereas the second metabolite, 2'-C-methyl-DAPN-TP, behaves as an adenosine base analog. In vitro assays suggest that both metabolites are inhibitors of NS5B-mediated RNA polymerization. Additional factors, such as rNAI-TP incorporation efficiencies, intracellular rNAI-TP levels, and competition with natural ribonucleotides, were examined in order to further characterize the potential role of each nucleotide metabolite in vivo Finally, we found that although both 2'-C-methyl-GTP and 2'-C-methyl-DAPN-TP were weak substrates for human mitochondrial RNA (mtRNA) polymerase (POLRMT) in vitro, DAPN-PD1 did not cause off-target inhibition of mtRNA transcription in Huh-7 cells. In contrast, administration of BMS-986094, which also generates 2'-C-methyl-GTP and previously has been associated with toxicity in humans, caused detectable inhibition of mtRNA transcription. Metabolism of BMS-986094 in Huh-7 cells leads to 87-fold higher levels of intracellular 2'-C-methyl-GTP than DAPN-PD1. Collectively, our data characterize DAPN-PD1 as a novel and potent antiviral agent that combines the delivery of two active metabolites.
Assuntos
Adenosina/análogos & derivados , Antivirais/farmacologia , Guanosina Monofosfato/análogos & derivados , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Pró-Fármacos/farmacologia , Sofosbuvir/farmacologia , Adenosina/farmacologia , Linhagem Celular , RNA Polimerases Dirigidas por DNA/metabolismo , Guanosina Monofosfato/farmacologia , Humanos , RNA/metabolismo , RNA Mitocondrial , RNA Viral/metabolismo , Ribonucleosídeos/metabolismo , Transcrição Gênica/efeitos dos fármacos , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacosRESUMO
INTRODUCTION: Children's diets in the U.S. typically fail to meet dietary recommendations, contributing to associated adverse health outcomes. The Healthy, Hunger-Free Kids Act (HHFKA) of 2010 required the U.S. government to update nutrition standards for school meals to align with the Dietary Guidelines for Americans (DGAs). This study estimates the evolving impact of substituting school-prepared food for home-prepared food on overall daily diet quality and by subcomponents of diet quality. Subgroup analyses are performed by race/ethnicity and income. METHODS: Two, nonconsecutive days of dietary recall data from the National Health and Nutrition Examination Survey (2005-March 2020) are used to calculate schoolchildren's Healthy Eating Index (HEI)-2020 scores. The study includes children with complete two-day dietary intakes who attend kindergarten through twelfth grade in a school offering lunch. An individual-level fixed effects regression is employed to examine the relationship of school food consumption on HEI-2020 scores before and after HHFKA-mandated changes in nutrition standards. Analyses were conducted on September 23, 2023. RESULTS: Prior to changes in standards (2005-2008), school food did not impact diet quality within the overall group of children. In 2009-2012, positive associations between school food and diet quality emerged for low-income students and for non-Hispanic Black students. By 2013-2020, improvements were seen across all groups. The association between school food and diet quality was most attributable to more favorable consumption of dairy, fruit, whole grains, refined grains, added sugars and saturated fats. CONCLUSIONS: HHFKA-based nutrition standards were associated with beneficial dietary changes and reduced dietary disparities for children across diverse backgrounds.
Assuntos
Serviços de Alimentação , Renda , Política Nutricional , Instituições Acadêmicas , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Dieta Saudável/normas , Etnicidade , Serviços de Alimentação/normas , Serviços de Alimentação/estatística & dados numéricos , Inquéritos Nutricionais , Estados Unidos , Grupos RaciaisRESUMO
OBJECTIVE: To examine how increasing vegetable consumption from foods prepared at home (FAH) and foods prepared away from home (FAFH) would impact energy, dietary fibre and Na (sodium) intakes in the U.S.A. DESIGN: Using data from the 20032004 U.S. National Health and Nutrition Examination Survey, dietary intake data from two separate days were fitted with a first-difference (fixed-effects) model. Vegetables consumed from all sources, including mixed foods and juices, were disaggregated and expressed as amounts equivalent to one cup of whole vegetables. SETTING: Nationally representative sample of the U.S. population. SUBJECTS: Individuals aged 2 years and above reporting 2 d of dietary intake data in 20032004 (n 7647). RESULTS: Holding constant the total amount of food consumed, consuming an additional cup of tomatoes and potatoes from FAFH increases energy intake by respectively 1522 and 665 kJ, as compared with 246 and 367 kJ for FAH. Each additional cup of tomatoes from FAH is associated with an additional 179 mg of Na, compared with 113 mg for FAFH. All vegetable consumption increases fibre intake, except for potatoes and tomatoes from FAFH. Dark green and orange vegetables from FAH add the largest amount of fibre (1.38 g/cup). CONCLUSIONS: Because U.S. consumers frequently consume vegetables as part of mixed foods that add energy and Na, heavier consumption of vegetables as currently prepared raises the energy content and Na density of the overall diet. This is particularly true for vegetables prepared away from home.
Assuntos
Dieta , Fibras na Dieta/administração & dosagem , Ingestão de Energia , Manipulação de Alimentos , Sódio/administração & dosagem , Solanum lycopersicum , Solanum tuberosum , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Inquéritos sobre Dietas , Comportamento Alimentar , Feminino , Serviços de Alimentação , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Estados Unidos , Verduras , Adulto JovemRESUMO
The Supplemental Nutrition Assistance Program (SNAP) provides millions of low-income Americans food benefits and other forms of nutrition assistance. Evidence indicates that SNAP reduces food insecurity. However, there is a concern that the food benefit may increase the demand for less healthy foods more than healthier foods, thereby reducing the overall nutritional quality of the participant's food basket. This paper aims to examine the association of SNAP participation with the nutritional quality of food-at-home purchases of low-income households and to investigate the potential heterogeneity among consumers with different levels of nutrition attitude. This analysis used food purchase data from the USDA National Household Food Acquisition and Purchase Survey (FoodAPS). Our study sample included 2,218 low-income households, of which 1,184 are SNAP participants, and 1,034 are income-eligible nonparticipants. Multivariate regressions were performed to explore the SNAP-nutritional quality association. A household's nutrition attitude was measured using its response to a question on whether the household searched for nutrition information online in the last 2 months. Households that affirmed they had an online nutrition search were treated as nutrition-oriented households (21.2% of the low-income sample), and households that did not were considered less nutrition-oriented households (78.8%). For robustness, we also created an alternative nutrition attitude measure based on reported use of the nutrition facts label. We found that among less nutrition-oriented households, SNAP participants had a statistically significant 0.097 points (p = 0.018) lower Guiding Stars rating than low-income nonparticipants. However, there was no significant SNAP-nutritional quality association among nutrition-oriented households. In conclusion, SNAP participation was associated with lower nutritional quality of food purchases among less nutrition-oriented households, but not among nutrition-oriented households. The results suggest that the intended nutritional benefits of restrictions on purchases of healthy foods may not reach the subgroup of nutrition-oriented SNAP participants.
Assuntos
Comportamento do Consumidor/estatística & dados numéricos , Comportamento Alimentar , Assistência Alimentar/estatística & dados numéricos , Valor Nutritivo , Pobreza , Adolescente , Adulto , Idoso , Características da Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais/estatística & dados numéricos , Estados Unidos , United States Department of Agriculture/estatística & dados numéricos , Adulto JovemRESUMO
The benefit calculation of the Supplemental Nutrition Assistance Program (SNAP), formerly the Food Stamp Program, is based primarily on results of the Thrifty Food Plan (TFP) developed by the USDA. By using a nonlinear mathematical programming approach, the TFP provides a dietary pattern recommendation that deviates the least from low-income consumers' consumption pattern, meets dietary guidelines, and is economical. The TFP stipulates that all foods should be purchased at stores and prepared at home [food at home (FAH)] and excludes an important part of current consumers' diet, food away from home (FAFH). Our purpose was to evaluate the feasibility and nutritional impact of adding a FAFH dimension into the TFP model framework. Measures of energy density, nutrients and food group composition, and the overall diet quality measured by the Healthy Eating Index 2005 were calculated and compared across the TFP, the TFP with FAFH, and low-income consumers' diet pattern. Our results indicated that considering moderate FAFH in the TFP yielded similar nutrient and food group composition as the original TFP while greatly increasing the practicality and adaptability of the recommended dietary pattern. These findings may be used by nutrition educators to develop healthful FAFH choices for individuals receiving SNAP benefits.
Assuntos
Comportamento Alimentar , Alimentos/economia , Dieta , Humanos , Necessidades Nutricionais , Pobreza , Estados Unidos , United States Department of AgricultureRESUMO
INTRODUCTION: Since 2005, the federal government's Dietary Guidelines for Americans have recommended at least half of total grain intake be whole grains. Beginning with the 2012-2013 school year, the U.S. Department of Agriculture updated school meal regulations to align with this recommendation. METHODS: Nationally representative food consumption survey data spanning 1994-2014 were analyzed in 2018 to construct a sample of 17,016 schoolchildren aged 5-19 years. Regression models were used to examine changes in whole grain/total grain intake by food source. For school-obtained foods, changes in whole grain intake are decomposed into changes in propensity (proportion of students consuming whole grains) and intensity (amount consumed by whole grain consumers). RESULTS: The whole grain/total grain ratio from all sources fell from 9.67% (1994-1998) to 7.6% (2005-2006) before climbing to 13.48% (2013-2014). Home-prepared foods topped the whole grain/total grain ratio among all sources until surpassed by school foods in 2013-2014 (17.16% vs 21.48%). The whole grain/total grain ratio from school rose from 4.02% to 21.48% during 1994-2014. Among those consuming school foods, increased intensity contributed more than propensity to increases in whole grain intake from school between 2005-2010 and 2011-2012; the opposite occurred between 2011-2012 and 2013-2014 because of increasing propensity, from one in four to one in two students consuming whole grains. CONCLUSIONS: During 1994-2006, the whole grain/total grain ratio of schoolchildren's diets declined, contrary to expert advice. Following the 2012 U.S. Department of Agriculture school meal regulations, both the propensity and the intensity of whole grain consumption from school rose considerably, demonstrating the important role school meals may play in improving children's diets.
Assuntos
Refeições , Política Nutricional/tendências , Instituições Acadêmicas , Estudantes/estatística & dados numéricos , Grãos Integrais/normas , Adolescente , Adulto , Criança , Pré-Escolar , Ingestão de Energia , Feminino , Regulamentação Governamental , Humanos , Masculino , Inquéritos Nutricionais , Estados Unidos , Adulto JovemRESUMO
Hepatitis C virus (HCV) nucleoside inhibitors display pan-genotypic activity, a high barrier to the selection of resistant virus, and are some of the most potent direct-acting agents with durable sustained virologic response in humans. Herein, we report, the discovery of ß-d-2'-Br,2'-F-uridine phosphoramidate diastereomers 27 and 28, as nontoxic pan-genotypic anti-HCV agents. Extensive profiling of these two phosphorous diastereomers was performed to select one for in-depth preclinical profiling. The 5'-triphosphate formed from these phosphoramidates selectively inhibited HCV NS5B polymerase with no inhibition of human polymerases and cellular mitochondrial RNA polymerase up to 100 µM. Both are nontoxic by a variety of measures and display good stability in human blood and favorable metabolism in human intestinal microsomes and liver microsomes. Ultimately, a preliminary oral pharmacokinetics study in male beagles showed that 28 is superior to 27 and is an attractive candidate for further studies to establish its potential value as a new clinical anti-HCV agent.
Assuntos
Antivirais/farmacologia , Desoxirribonucleosídeos/farmacologia , Nucleotídeos de Desoxiuracil/farmacologia , Hepacivirus/efeitos dos fármacos , Pró-Fármacos/farmacologia , Animais , Antivirais/síntese química , Antivirais/farmacocinética , Linhagem Celular Tumoral , Desoxirribonucleosídeos/síntese química , Desoxirribonucleosídeos/farmacocinética , Nucleotídeos de Desoxiuracil/síntese química , Nucleotídeos de Desoxiuracil/farmacocinética , Cães , Descoberta de Drogas , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Humanos , Masculino , Microssomos Hepáticos/metabolismo , Pró-Fármacos/síntese química , Pró-Fármacos/farmacocinética , Proteínas não Estruturais Virais/antagonistas & inibidoresRESUMO
Human papillomavirus (HPV) DNA replication requires the viral origin recognition protein E2 and the presumptive viral replicative helicase E1. We now report for the first time efficient DNA unwinding by a purified HPV E1 protein. Unwinding depends on a supercoiled DNA substrate, topoisomerase I, single-stranded-DNA-binding protein, and ATP, but not an origin. Electron microscopy revealed completely unwound molecules. Intermediates contained two single-stranded loops emanating from a single protein complex, suggesting a bidirectional E1 helicase which translocated the flanking DNA in an inward direction. We showed that E2 protein partially inhibited DNA unwinding and that Hsp70 or Hsp40, which we reported previously to stimulate HPV-11 E1 binding to the origin and promote dihexameric E1 formation, apparently displaced E2 and abolished inhibition. Neither E2 nor chaperone proteins were detected in unwinding complexes. These results suggest that chaperones play important roles in the assembly and activation of a replicative helicase in higher eukaryotes. An E1 mutation in the ATP binding site caused deficient binding and unwinding of origin DNA, indicating the importance of ATP binding in efficient helicase assembly on the origin.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Conformação de Ácido Nucleico , Papillomaviridae/metabolismo , Proteínas Virais/metabolismo , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Sistema Livre de Células , Cloroquina/farmacologia , DNA/ultraestrutura , DNA Topoisomerases Tipo I/metabolismo , DNA Super-Helicoidal , Proteínas de Ligação a DNA/química , Eletroforese em Gel de Ágar , Humanos , Imuno-Histoquímica , Insetos , Microscopia Eletrônica , Modelos Biológicos , Mutação , Plasmídeos/metabolismo , Ligação Proteica , Proteínas Virais/químicaRESUMO
High rates of obesity among low-income populations have led some to question whether USDA's food assistance programs have contributed to this health problem. Using data from National Health and Nutrition Examination Surveys (NHANES), this study shows that the association between food assistance program participation and body weight measures has weakened over the past three decades. Earlier NHANES data show that program participants were more likely to be overweight than individuals who were eligible but not participating in the program. This was particularly true among white women. However, the more recent data show that these differences have vanished, as the BMI of the rest of the population has caught up to BMI levels of food stamps recipients.
Assuntos
Peso Corporal , Obesidade/epidemiologia , Pobreza/tendências , Assistência Pública/tendências , Adulto , Índice de Massa Corporal , Centers for Disease Control and Prevention, U.S. , Feminino , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Pobreza/estatística & dados numéricos , Assistência Pública/estatística & dados numéricos , Fatores Sexuais , Estados Unidos/epidemiologiaRESUMO
The genomes of human and animal papillomaviruses amplify in keratinocytes undergoing terminal squamous differentiation. Two approaches have been developed to facilitate the investigation into the requirement for viral DNA replication and its regulation outside the context of the host tissues. Under these conditions, the investigation can be conducted independently of viral genes required to re-establish the S-phase milieu in the differentiated keratinocytes to support viral DNA replication. The first method is transient replication in cell lines after transfection of a plasmid containing the viral origin of replication together with expression vectors of the necessary viral proteins that direct specific initiation from the origin. The second is cell-free replication in which purified viral replication proteins are complemented by cell extracts to initiate origin-specific replication. The two methods have identified the origin, the viral E1 and E2 proteins necessary for initiation, their functions, and the host factors that are required to support and regulate the viral DNA replication. These two methods are complementary in providing answers and insights that either one alone may not be able to achieve. This chapter provides a practical guide to these two replication assays.
Assuntos
Replicação do DNA , DNA Viral/genética , Papillomaviridae/genética , Replicação Viral , Animais , Linhagem Celular , DNA Viral/isolamento & purificação , Eletroforese em Gel de Ágar , Eletroforese em Gel de Poliacrilamida , Vetores Genéticos , Humanos , Queratinócitos/citologia , Queratinócitos/virologia , Papillomaviridae/fisiologia , Biossíntese de Proteínas , Proteínas Virais/genéticaRESUMO
OBJECTIVES: Trends between 1977/1978 and 1994/1998 in the prevalence, amounts, and sources of soft drink consumption were examined among youth age 6 to 17 years. DESIGN: Dietary intake data were examined from three national surveys: the Nationwide Food Consumption Survey 1977/1978 (n=8,908), and the combined Continuing Survey of Food Intakes by Individuals 1994/1996, and the Supplemental Children's Survey 1998 (n=3,177). Soft drinks were defined as carbonated beverages (all United States Department of Agriculture database codes starting with 924) and included flavored waters and juice drinks. Subjects/Setting A national sample of youth ages 6 to 17 years were interviewed for each of the 3 surveys. STATISTICAL ANALYSIS: t tests were conducted to examine between-survey changes in soft drink consumption and sources of soft drinks. RESULTS: The prevalence of soft drink consumption among youth ages 6 to 17 years increased 48%, from a prevalence of 37% in 1977/1978 to 56% in 1994/1998. Mean intake of soft drinks more than doubled, from 5 fl oz to 12 fl oz per day. Although the home environment remained the largest source of children's soft drink access, an increasing share was obtained from restaurants and fast-food establishments (+53%), vending machines (+48%), and other sources (+37%). CONCLUSIONS: Away-from-home sources of soft drink are an important factor for dietitians to consider when evaluating the dietary intake and nutritional status of youths.
Assuntos
Fenômenos Fisiológicos da Nutrição do Adolescente , Bebidas Gaseificadas/estatística & dados numéricos , Fenômenos Fisiológicos da Nutrição Infantil , Ingestão de Líquidos , Adolescente , Criança , Ingestão de Energia , Comportamento Alimentar , Feminino , Humanos , Entrevistas como Assunto , Masculino , Inquéritos Nutricionais , Prevalência , Estados UnidosRESUMO
With the elderly becoming an ever-larger proportion of the American population, their dietary well-being is of increasing concern. In particular, lower-income elderly may face special challenges in maintaining a healthful diet. This group makes up a sizeable proportion of the elderly population; we estimate that almost 1 in 5 (19%) of the elderly have household incomes at or below 130% of the federal poverty level, the income level that generally qualifies a household to participate in the federal Food Stamp Program. Here we examine the dietary intakes and related behaviors, as well as the food security status, of lower- and higher-income elderly and review major US government food and nutrition assistance programs that can be of benefit to the elderly, particularly those of low income. Our subjects are individuals 60 years of age and over, living in community (noninstitutionalized) settings. Data on dietary intakes and behaviors were obtained from the US Department of Agriculture's Continuing Survey of Food Intakes by Individuals (CSFII), 1994-96. Food security data were obtained from the 1999 Current Population Survey (CPS), conducted by the US Census Bureau. For both the CSFII and the CPS, sampling weights were used to generate nationally representative estimates. We found that lower-income elderly consume significantly fewer calories than higher-income elderly, fewer servings of major Food Guide Pyramid food groups, and most nutrients. Approximately 6% of elderly households report some degree of food insecurity. Although food and nutrition assistance programs can benefit elderly individuals, many do not participate. Many lower-income elderly also face physiological and social obstacles to obtaining a healthful diet. How best to meet these varied needs is a challenge for nutrition educators, researchers, and policy makers.
Assuntos
Dieta/normas , Serviços de Alimentação/estatística & dados numéricos , Renda , Pobreza , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Ingestão de Energia , Feminino , Abastecimento de Alimentos/economia , Abastecimento de Alimentos/normas , Planejamento em Saúde , Nível de Saúde , Humanos , Masculino , Inquéritos Nutricionais , Fatores Socioeconômicos , Estados UnidosRESUMO
OBJECTIVE: To examine changes, between 1977-78 and 1994-96, in the quantity and quality of food Americans consumed that was prepared at home versus away from home. DESIGN: Data were obtained from nationwide surveys of food consumption conducted by the US Department of Agriculture (USDA) in 1977-78 and 1994-96. To maximize comparability, we used "day 1" dietary data, which both surveys collected via 24-hour recall. SUBJECTS/SETTINGS: Individuals 2 years of age and over were selected. USDA sampling weights were used to generate nationally representative estimates. VARIABLES MEASURED: We categorized foods by preparation at home or at restaurants, fast-food establishments, schools/day care, and other non-home locations. We assessed percent calories from total fat and saturated fat, and the cholesterol, sodium, fiber, calcium, and iron densities of foods prepared at home versus those prepared away from home. STATISTICAL ANALYSES: T tests were calculated using accepted procedures to adjust for survey design effects. RESULTS: Between 1977-78 and 1994-96, consumption of food prepared away from home increased from 18% to 32% of total calories. Meals and snacks based on food prepared away from home contained more calories per eating occasion, and "away" food was higher in total fat and saturated fat on a per-calorie basis than at-home food. "Away" food contained less dietary fiber, calcium, and iron on a per-calorie basis. Among adults but not children, food prepared away from home was more sodium and cholesterol dense. IMPLICATIONS: When developing intervention messages and strategies, nutrition educators need to be aware of the increasing role of "away" food in Americans' diets.
Assuntos
Comportamento de Escolha , Dieta/tendências , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Inquéritos sobre Dietas , Comportamento Alimentar , Feminino , Preferências Alimentares , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Restaurantes , Estados UnidosRESUMO
Childhood obesity is associated with a number of serious health risks that can persist into adulthood. While trends in food away from home and fast-food consumption have paralleled trends in childhood obesity, it is important to identify whether this is a causal relationship. This paper reviews recent literature in this area to summarize if there is a consensus in research findings. We group the literature into two areas - consumption of and access to food away from home (FAFH). While no consensus findings have been reached in either area, the evidence of an association between FAFH consumption and childhood obesity has gained strength. Further, there is evidence that FAFH meals add calories to children's diets. The literature on the role of FAFH access and childhood obesity has continued producing mixed results.
RESUMO
Taxing unhealthy foods has been proposed as a means to improve diet and health by reducing calorie intake and raising funds to combat obesity, particularly sugar-sweetened beverages (SSBs). A growing number of studies have examined the effects of such food taxes, but few have estimated the weight-loss effects. Typically, a static model of 3500 calories for one pound of body weight is used, and the main objective of the study is to demonstrate its bias. To accomplish the objective, we estimate income-segmented beverage demand systems to examine the potential effects of a SSB tax. Elasticity estimates and a hypothetical 20 percent effective tax rate (or about 0.5 cent per ounce) are applied to beverage intake data from a nationally representative survey, and we find an average daily reduction of 34-47 calories among adults and 40-51 calories among children. The tax-induced energy reductions are translated into weight loss using both static and dynamic calorie-to-weight models. Results demonstrate that the static model significantly overestimates the weight loss from reduced energy intake by 63 percent in year one, 346 percent in year five, and 764 percent in year 10, which leads to unrealistic expectations for obesity intervention strategies. The tax is estimated to generate $5.8 billion a year in revenue and is found to be regressive, although it represents about 1 percent of household food and beverage spending.
Assuntos
Bebidas Gaseificadas/economia , Obesidade/prevenção & controle , Impostos , Redução de Peso/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Ingestão de Energia/fisiologia , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Estados Unidos , Adulto JovemRESUMO
OBJECTIVES. High rates of overweight and obesity among low-income children have led some to question whether participation in US domestic food assistance programs contributes to this health problem. We use multiple years of data to examine trends in children's body weight and participation in the Food Stamp Program (FSP) or Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). Specifically, we assess whether a consistent relationship between program participation and body weight exists over time. METHODS. Data from multiple waves of the National Health and Nutrition Examination Surveys (NHANES) are used to examine the relationship between children's body weight and food assistance programs between 1976 and 2002. Linear regression models are used to estimate BMI and logit models are used to predict the probabilities of at-risk of overweight and overweight. Food assistance program participants (either FSP or WIC participants depending on age) are compared with income eligible non-participants and higher income children. RESULTS. Results show no systematic relationship over time between FSP participation and weight status for school-aged children (age 5-17). For children aged 2-4, no differences in weight status between WIC participants and eligible non-participants were found. However, recent data show some differences between WIC participants and higher income children. CONCLUSIONS. Our analysis does not find evidence of a consistent relationship between childhood obesity and participation in the FSP or WIC programs.
Assuntos
Peso Corporal , Abastecimento de Alimentos/estatística & dados numéricos , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Pobreza/estatística & dados numéricos , Assistência Pública/estatística & dados numéricos , Adolescente , Negro ou Afro-Americano/estatística & dados numéricos , Fatores Etários , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Lineares , Modelos Logísticos , Masculino , Americanos Mexicanos/estatística & dados numéricos , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Medição de Risco , Fatores de Risco , Fatores de Tempo , Estados Unidos , População Branca/estatística & dados numéricosRESUMO
The purpose of this research was to investigate the associations between misperception of body weight and sociodemographic factors such as food stamp participation status, income, education, and race/ethnicity. National Health and Nutrition Examination Survey (NHANES) data from 1999-2004 and multivariate logistic regression are used to estimate how sociodemographic factors are associated with (i) the probability that overweight adults misperceive themselves as healthy weight; (ii) the probability that healthy-weight adults misperceive themselves as underweight; and (iii) the probability that healthy-weight adults misperceive themselves as overweight. NHANES data are representative of the US civilian noninstitutionalized population. The analysis included 4,362 men and 4,057 women. BMI derived from measured weight and height was used to classify individuals as healthy weight or overweight. These classifications were compared with self-reported categorical weight status. We find that differences across sociodemographic characteristics in the propensity to underestimate or overestimate weight status were more pronounced for women than for men. Overweight female food stamp participants were more likely to underestimate weight status than income-eligible nonparticipants. Among healthy-weight and overweight women, non-Hispanic black and Mexican-American women, and women with less education were more likely to underestimate actual weight status. We found few differences across sociodemographic characteristics for men. Misperceptions of weight are common among both overweight and healthy-weight individuals and vary across socioeconomic and demographic groups. The nutrition education component of the Food Stamp Program could increase awareness of healthy body weight among participants.
Assuntos
Peso Corporal , Sobrepeso/psicologia , Autoimagem , Magreza/psicologia , Etnicidade , Feminino , Humanos , Masculino , Razão de Chances , Sobrepeso/epidemiologia , Fatores Socioeconômicos , Magreza/epidemiologia , Estados Unidos/epidemiologiaRESUMO
The human papillomavirus (HPV) DNA replication origin (ori) shares a common theme with many DNA control elements in having multiple binding sites for one or more proteins spaced over several hundreds of base pairs. The HPV type 11 ori spans 103 bp and contains three palindromic E2 binding sites (E2BS-2, E2BS-3, and E2BS-4) for the dimeric E2 ori binding protein. These sites are separated by 64 and 3 bp. E2BS-1 is located 288 bp upstream of E2BS-2 and is not required for efficient transient or cell-free replication. In this study, electron microscopy was used to visualize complexes of HPV-11 DNA ori bound by purified E2 protein. DNA containing only E2BS-2 showed a single E2 dimer bound. DNA containing E2BS-3 and E2BS-4 showed two side-by-side E2 dimers, while DNA containing E2BS-2, E2BS-3, and E2BS-4 exhibited a large disk/ring-shaped protein particle bound, indicating that the DNA had been remodeled into a discrete complex, likely containing an E2 hexamer. With all four binding sites present, up to 27% of the DNA molecules were arranged into loops by E2, the majority of which spanned E2BS-1 and one of the other three sites. Studies on the dependence of looping on salt, ATP, and DTT using full-length E2 and an E2 protein containing only the carboxyl-terminal DNA binding and protein dimerization domain suggest that looping is dependent on the N-terminal domain and factors that may affect the manner in which E2 scans DNA for binding sites. The role of these structures in the modeling and regulation of the HPV-11 ori is discussed.
Assuntos
Papillomavirus Humano 11/genética , Nucleoproteínas/metabolismo , Origem de Replicação , Proteínas Virais/química , Proteínas Virais/metabolismo , Trifosfato de Adenosina/metabolismo , Sequência de Bases , Sítios de Ligação , Sondas de DNA , DNA Viral/genética , DNA Viral/metabolismo , DNA Viral/ultraestrutura , Dimerização , Humanos , Modelos Biológicos , Dados de Sequência Molecular , Peso Molecular , Mutação , Conformação de Ácido Nucleico , Nucleoproteínas/isolamento & purificação , Plasmídeos , Regiões Promotoras Genéticas , Ligação Proteica , Estrutura Secundária de Proteína , Proteínas Virais/genética , Proteínas Virais/isolamento & purificação , Proteínas Virais/ultraestruturaRESUMO
Human and animal papillomavirus DNA replicates as multicopy nuclear plasmids. Replication requires two viral proteins, the origin-recognition protein E2 and the replicative DNA helicase E1. Using genetic, biochemical, and immunofluorescence assays, we demonstrated that efficient nuclear import of the human papillomavirus (HPV) type 11 E1 protein depends on a codominant bipartite nuclear localization sequence (NLS) and on phosphorylation of the serine residues S89 and S93 by the mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase, and c-Jun N-terminal protein kinase. The NLS and the MAPK substrates are located within a 50-amino-acid-long peptide near the amino terminus, previously designated the localization regulatory region (LRR). The downstream NLS overlaps the cyclin-binding motif RRL, which is necessary for phosphorylation by the cyclin-dependent kinases to inactivate a dominant nuclear export sequence, also in the LRR. Alanine mutations of the MAPK substrates significantly impaired nuclear import, whereas phospho-mimetic mutations partially restored nuclear import. We further identified two MAPK docking motifs near the C terminus of E1 that are conserved among E1 proteins of many HPVs and bovine papillomavirus type 1. Mutations of these MAPK docking motifs or addition of specific MAPK inhibitors significantly reduced nuclear import. Interestingly, a fraction of the NLS-minus E1 protein was cotransported with the E2 protein into the nucleus and supported transient viral DNA replication. In contrast, E1 proteins mutated in the MAPK docking motifs were completely inactive in transient replication, an indication that additional properties were adversely affected by those changes.
Assuntos
DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Papillomavirus Humano 11/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Sinais de Localização Nuclear/metabolismo , Proteínas Virais/metabolismo , Transporte Ativo do Núcleo Celular , Motivos de Aminoácidos , Animais , Sítios de Ligação/genética , Linhagem Celular , Núcleo Celular/química , Chlorocebus aethiops , DNA Helicases/química , DNA Helicases/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Papillomavirus Humano 11/genética , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Microscopia de Fluorescência , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Modelos Biológicos , Mutagênese Sítio-Dirigida , Sinais de Localização Nuclear/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Virais/química , Proteínas Virais/genética , Replicação Viral/genéticaRESUMO
This is the second part of a 2-part article that summarizes a review of research designs for assessing the impact of the USDA's food assistance and nutrition programs on nutrition and health. The first part focused on the research designs for evaluating ongoing national programs. Here, the random experiment and 3 quasi-experimental designs that can be used to evaluate the impacts of demonstration projects are reviewed.