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1.
Ann Allergy Asthma Immunol ; 110(5): 340-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23622004

RESUMO

BACKGROUND: Community-based studies of obesity, asthma, biomarkers of oxidative stress, and adipokines among low-income, urban, minority populations are lacking. Oxidative stress, perhaps modulated by adipokines, may increase airway inflammation in obese individuals. OBJECTIVES: To characterize associations between obesity and asthma in a low-income, urban, minority community and evaluate adipokines, biomarkers of inflammation, and oxidant-antioxidant balance in association with asthma and obesity. METHODS: A door-to-door evaluation of asthma and obesity prevalence was performed in a low-income housing development. Nonsmoking adults and children underwent additional evaluation, including allergy skin testing, and measures of serum adipokines, and indicators of oxidative stress in blood and exhaled breath. RESULTS: The prevalences of current asthma and a body mass index in the 85th percentile or higher were 15.8% and 35.3%, respectively, among 350 nonsmokers older than 4 years. Asthma and obesity were not associated with one another (odds ratio, 1.0; 95% confidence interval, 0.55-1.84). Among 116 nonsmoking participants who underwent biomarker evaluation, obesity was not associated with exhaled nitric oxide. In multivariate logistic models that adjusted for age category, sex, and a body mass index in 85th percentile or higher, leptin concentrations in the highest quartile were associated with asthma (odds ratio, 8.34; 95% confidence interval, 1.29-50.2) but not with atopy. Adiponectin was associated with total antioxidant capacity in exhaled breath. CONCLUSION: Asthma and obesity, although both common in a low-income, minority community, were not associated with one another. Nevertheless, adipokines were associated with asthma status and with markers of oxidative stress in the lungs, providing some support for an adipokine-inflammatory mechanistic link between the two conditions.


Assuntos
Asma/epidemiologia , Obesidade/epidemiologia , Adiponectina/sangue , Adulto , Asma/sangue , Biomarcadores/análise , Pré-Escolar , Coleta de Dados , Feminino , Humanos , Leptina/sangue , Masculino , Grupos Minoritários , Obesidade/sangue , Estresse Oxidativo , Pobreza , População Urbana
2.
Br J Nutr ; 109(12): 2219-30, 2013 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-23200261

RESUMO

Tomatoes may have beneficial effects on prostate health. Efficacy trials would require long-term adherence to high levels of tomato product (TP) consumption. Therefore, factors that affect adherence in men most at risk and whether increased consumption of TP negatively affects diet and health are important concerns. Cancer-free African­American (AA) men (n 36) with mean serum prostate-specific antigen of 7.4 SD 5.6) ng/ml were randomised to consume one serving of TP/d or a control diet for 3 months. Mean intervention group lycopene intake rose to 464%, with negligible control group increase. Plasma lycopene levels rose by 53 and 40% in the intervention group in months 1 and 3, respectively (P < 0.0001), with no control group change. The intervention group's barriers to adherence score was inversely associated with both dietary (r -0.49, P = 0.02) and plasma lycopene concentration (r -0.37, P = 0.02). Their TP disadvantage score negatively correlated with the 3-month plasma lycopene concentrations (r -0.37, P = 0.008) and their weekly incentives and impediments were remarkably stable, 'concern for prostate health' being the most consistent over time. 'Liking tomatoes' and 'study participation' decreased in citation frequency at weeks 6 and 9, respectively. No major shifts occurred in dietary cholesterol or saturated fat, with no adverse effects on gastrointestinal complaints, serum total cholesterol, body weight or blood pressure. Lower socio-economic status AA men at higher prostate cancer risk can successfully achieve a whole food intervention goal with a corresponding rise in plasma lycopene concentrations, with no adverse effects on self-selected diet quality or health parameters.


Assuntos
Anticarcinógenos/sangue , Carotenoides/sangue , Dieta/métodos , Cooperação do Paciente , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/etnologia , Solanum lycopersicum , Negro ou Afro-Americano , Idoso , Análise de Variância , Humanos , Licopeno , Solanum lycopersicum/efeitos adversos , Solanum lycopersicum/química , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/prevenção & controle , Inquéritos e Questionários
3.
J Food Sci ; 77(10): C1109-14, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22950575

RESUMO

The objective of this study was to determine the influence of thermal processing on the assessment of tocopherols and carotenoids, as well as their isomer formation in tomatoes. The sliced tomatoes were heated in an oven at 100, 130, and 160 °C for 5, 10, and 20 min, then freeze-dried. Freeze-dried samples were finely ground and the analysis was performed on lyophilized samples. The average concentrations of total lycopene, lutein, ß-carotene, α-tocopherol, and γ-tocopherol in fresh tomatoes (in 100 g dry weight) were 21.2, 1.1, 2.7, 8.0, and 2.5 mg, respectively. Oven baking of tomato at 160 °C for 20 min led to a significant increase in the apparent measurement of lycopene, ß-carotene, and α-tocopherol content by 75%, 81%, and 32%, respectively. Heating induced isomerization of (all-E) to various (Z) isomers of lycopene, and we found that the total (Z)-lycopene proportion in the tomatoes increased with longer heating time. (All-E)-lycopene constituted 75.4% in fresh tomatoes and decreased to 52.5% in oven-baked tomatoes (160 °C, 20 min), while (5Z)-lycopene increased from 9.4% to 17.9% of total lycopene. However, ß-carotene release and isomerization was less influenced by the heat treatment than that of lycopene. These results suggested that thermal processes might break down cell walls and enhance the release of carotenoids and tocopherols from the matrix, as well as increase isomerization of lycopene and ß-carotene.


Assuntos
Carotenoides/análise , Luteína/análise , Solanum lycopersicum/química , alfa-Tocoferol/análise , beta Caroteno/análise , gama-Tocoferol/análise , Cromatografia Líquida de Alta Pressão , Manipulação de Alimentos/métodos , Temperatura Alta , Isomerismo , Licopeno , Vitaminas/análise
4.
Cancer Prev Res (Phila) ; 4(5): 711-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21430075

RESUMO

Consumption of tomato products is associated with a decreased risk of developing prostate cancer, and lycopene, the red carotenoid in the tomato, is a potent antioxidant that might contribute to this chemoprevention activity. A double-blind, randomized, placebo-controlled trial of 105 African American men veterans, recommended for prostate biopsy to detect cancer, was carried out to investigate whether oral administration of lycopene increases lycopene levels in blood and prostate tissue and lowers markers of oxidative stress. Urology patients were randomly assigned to receive 30 mg/d of lycopene as a tomato oleoresin or placebo for 21 days prior to prostate biopsy for possible diagnosis of prostate cancer. A total of 47 men had a diagnosis of prostate cancer, and 58 men had a diagnosis of benign prostate hyperplasia. Diet, smoking, and drinking habits were assessed. For the men receiving lycopene, the mean lycopene concentration increased from 0.74 ± 0.39 to 1.43 ± 0.61 µmol/L in plasma (P < 0.0001) and from 0.45 ± 0.53 to 0.59 ± 0.47 pmol/mg in prostate tissue (P = 0.005). No significant changes in the DNA oxidation product 8-oxo-deoxyguanosine and the lipid peroxidation product malondialdehyde were observed in prostate tissue and plasma, respectively, as a result of lycopene administration.


Assuntos
Antioxidantes/uso terapêutico , Carotenoides/uso terapêutico , Hiperplasia Prostática/prevenção & controle , Neoplasias da Próstata/prevenção & controle , Negro ou Afro-Americano , Idoso , Idoso de 80 Anos ou mais , Carotenoides/análise , Método Duplo-Cego , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Licopeno , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Estresse Oxidativo , Hiperplasia Prostática/etnologia , Neoplasias da Próstata/etnologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
5.
Cancer Epidemiol Biomarkers Prev ; 17(1): 212-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18199726

RESUMO

The extent of oxidative DNA damage is considered a biomarker of carcinogenic process and could be investigated in population studies using easily obtained cells. The oxidized DNA base adduct 8-hydroxy-2-deoxyguanosine (8-OHdG) released by enzymatic hydrolysis of DNA is commonly assayed by high performance liquid chromatography with electrochemical detection. It is expressed as a ratio of 8-OHdG to unoxidized deoxyguanosine. We modified and improved this method, determined the optimal time for harvesting buccal mucosa cells (BMC), assessed whether they mirror peripheral circulating blood cell DNA damage, and compared the anticoagulants, heparin, and EDTA for consistency in measurement of leukocyte 8-OHdG. Thirty-one healthy participants, randomized into two groups, donated BMC and blood samples. Samples were collected at baseline and either 3 or 7 days after baseline. Results showed no correlation between 8-OHdG/deoxyguanosine ratios in BMC and peripheral blood leukocytes at any time point regardless of harvest time. BMC had much higher oxidative DNA damage, but displayed a 25.6% reduction in the oxidized DNA adduct level (P < 0.04) at 3 days after baseline. Leukocytes collected in heparin and EDTA had similar 8OHdG/deoxyguanosine ratios; however, EDTA was preferred, as it produced a clean nuclear pellet without hemoglobin contamination, and the results were less variable. This improved assay shows within subject stability over time in both leukocyte and BMC DNA damage, increasing the probability that small intervention differences can be detected in healthy subjects. Buccal cells provide an accessible pool of epithelial cells that represents higher levels of DNA damage than circulating leukocytes.


Assuntos
Biomarcadores , DNA/genética , Desoxiguanosina/análogos & derivados , Mucosa Bucal/citologia , Estresse Oxidativo/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina , Adolescente , Adulto , Idoso , Adutos de DNA/genética , Dano ao DNA , Desoxiguanosina/metabolismo , Estudos de Viabilidade , Feminino , Heparina/farmacologia , Humanos , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/cirurgia
6.
Mol Nutr Food Res ; 52(1): 114-30, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18080240

RESUMO

Both genetic and environmental influences may be involved in etiology of prostate health and prostate cancer. These include ethnic origin, family history, smoking, and diet. Adiposity and excess energy intake are potentially distinct risk factors and positive associations with prostate cancer risk for both were observed among case-control and cohort studies. Some epidemiological studies support an association between dietary fat, particularly saturated or animal fats, and prostate cancer risk. Of these, several suggest reduced risk with low-fat diets high in n-3 fatty acids and increased risk with high-fat diets rich in n-6 fatty acids. Others suggested association with higher meat intake, possibly due to heterocyclic amines and polycyclic aromatic hydrocarbons, produced during grilling or frying. Positive association of prostate cancer risk with dairy intake could involve alpha-methylacyl-CoA racemase activity (required for beta-oxidation of phytanic acid present in dairy products and red meat) or the suppression of vitamin D activity by calcium. Inverse associations were observed with dietary intake of plant foods. These include cereals, soy products, and fruit and vegetable sources of carotenoids. Numerous plant constituents may act synergistically in the prevention and inhibition of prostate disorders. These diet-risk associations may lead to future individualized diet recommendations based upon genetic polymorphisms.


Assuntos
Dieta , Neoplasias da Próstata , Adiposidade , Animais , Carotenoides , Laticínios , Gorduras na Dieta/administração & dosagem , Grão Comestível , Ingestão de Energia , Metabolismo Energético , Frutas , Humanos , Masculino , Carne , Obesidade/complicações , Polimorfismo Genético , Neoplasias da Próstata/etiologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/prevenção & controle , Fatores de Risco , Alimentos de Soja , Chá , Verduras
7.
J Nutr ; 138(1): 185S-192S, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18156423

RESUMO

The purpose of this article is to describe the baseline design elements and sample characteristics of the Behavior Change Consortium (BCC) Dietary Measurement studies for each of the 7 sites that comprised the BCC Nutrition Working Group (NWG). This article summarizes the project designs, including descriptions of diverse study populations, primary assessment methods, and study outcomes. Common measures used across sites included the National Cancer Institute (NCI) Fruit and Vegetable Screener, NCI Percentage Energy from Fat Screener, 24-h dietary recalls, and a single- or 2-item fruit and vegetable measure. Data on sociodemographic characteristics, body weight and height, smoking status, and serum carotenoids were also collected. Study design information such as assessment time points, as well as baseline sample characteristics, is also described. This paper provides the overall framework and descriptive information and serves as the reference for the BCC NWG special supplement.


Assuntos
Terapia Comportamental , Avaliação Nutricional , Projetos de Pesquisa , Gorduras na Dieta , Comportamento Alimentar , Feminino , Frutas , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Verduras
8.
J Nutr ; 138(1): 200S-204S, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18156425

RESUMO

Five sites participating in the NCI Behavior Change Consortium administered the NCI Fruit and Vegetable Screener (FVS) and multiple, nonconsecutive 24-h dietary recall interviews (24HR) to 590 participants. Three sites also obtained serum carotenoids (n = 295). Participants were primarily female, ethnically diverse, and varied by age and education. Correlations between 24HR and FVS by site ranged from 0.31 (P = 0.07) to 0.47 (P < 0.01) in men and from 0.43 to 0.63 (P < 0.01) in women. Compared with 24HR, FVS significantly (P < 0.05) overestimated intake at 2 of 4 sites for men and all 4 sites for women. Differences in estimated total servings of fruits and vegetables/d ranged from 0.16 to 3.06 servings. On average, the FVS overestimated intake by 1.76 servings in men and 2.11 servings in women. Alternative FVS scoring procedures and a 1-item screener lowered correlations with 24HR as well as serum carotenoids but alternate scoring procedures generally improved estimations of servings.


Assuntos
Carotenoides/sangue , Frutas , Rememoração Mental , Inquéritos Nutricionais , Verduras , Adulto , Terapia Comportamental , Dieta , Comportamento Alimentar , Feminino , Humanos , Masculino , National Cancer Institute (U.S.) , Avaliação Nutricional , Estados Unidos
9.
J Zoo Wildl Med ; 38(2): 201-16, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17679503

RESUMO

Complete physical examinations and biomedical sample collection were performed on 70 free-ranging ring-tailed lemurs (Lemur catta) from three different habitats in the Beza Mahfaly Special Reserve (BMSR), in southern Madagascar, to assess the impact of humans and habitat on lemur health. Lemurs were chemically immobilized with ketamine and diazepam administered via blow darts for concurrent biomedical, morphometric, and behavioral studies. Subsets of the animals had blood analyzed for hematology, serum chemistry, micronutrients, fat-soluble vitamins (vitamins A, D, and E), measures of iron metabolism, and polymerase chain reaction assays (PCR) for Toxoplasma gondii, Hemoplasma spp., Bartonella spp., Ehrlichia spp., Anaplasma phagocytophilum, and Neorickettsia risticii. Results were compared on the basis of gender and the habitats at the study site: reserve (intact gallery forest), degraded (human inhabited and altered), and marginal (dry didieracea forest with heavy grazing and tree cutting). Levels of vitamin D, triglycerides, and cholesterol, and measures of iron metabolism for BMSR lemurs were greater than those previously reported for a free-ranging lemur population (Tsimanampetsotsa Strict Nature Reserve, Madagascar) with less access to foods of anthropogenic origin. BMSR ring-tailed lemurs from a habitat with less water (marginal) had higher sodium (P = 0.051), chloride (P = 0.045), osmolality (P = 0.010), and amylase (P = 0.05) levels than lemurs from other BMSR habitats, suggesting that these lemurs were less hydrated. Vitamin D levels of male lemurs were higher (P = 0.011) than those of females at BMSR, possibly because of differences in sunning behavior or differential selection of food items. The biological significance is uncertain for other parameters with statistically significant differences. All samples tested (n = 20) were negative for the pathogens tested using PCR assays. Continued concurrent biomedical and ecological research is needed at BMSR to confirm these results and determine their association with population mortality and fecundity rates.


Assuntos
Análise Química do Sangue/veterinária , Lemur , Estado Nutricional , Exame Físico/veterinária , Animais , Animais Selvagens , Bactérias/isolamento & purificação , Conservação dos Recursos Naturais , Feminino , Testes Hematológicos/veterinária , Lemur/microbiologia , Lemur/parasitologia , Lemur/fisiologia , Madagáscar , Masculino , Doenças Parasitárias em Animais/epidemiologia , Valores de Referência , Fatores Sexuais
10.
J Nutr ; 137(6): 1415-22, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17513400

RESUMO

Previous work using an adolescent rat model for breast cancer showed increased tumor occurrence in rats fed a chemopreventive dose of vitamin A. Preclinical models for nutrient-cancer interactions utilizing defined diets do not replicate the complexity of the human diet and may be inadequate to investigate food patterns associated with reduced cancer risk in humans. To evaluate this concept, the effects of vitamin A on sexual maturation, mammary gland development, and sensitivity to carcinogenesis were determined in the context of a human food-based diet (whole food diet). At 20 d of age (p20), female rats received either a whole-food diet with adequate levels of vitamin A, a diet with a 5.5-fold increase in vitamin A from fruits and vegetables (S diet), or a diet with a 6.2-fold increase in vitamin A provided as retinyl palmitate (RP diet). To determine the effect of dietary intervention on pubertal mammary gland development, the dietary intervention period was restricted to postnatal d 21-63. Rats were injected with 50 mg 1-methyl-1-nitrosourea/kg body weight at d 66. Compared with adolescent rats that consumed the Ad diet, consumption of S and RP diets reduced mammary cancer multiplicity (relative risk approximately 0.7, P < or = 0.002), which was associated with a reduction in alveolar gland development. The S diet suppressed the onset of sexual maturation (P < 0.001) and inhibited markers of mammary alveologenesis more than the RP diet. These data demonstrate that the amount and source of vitamin A consumed by adolescent female rats can influence the onset of puberty, mammary gland alveolar development, and breast cancer risk and highlight the relevance of utilizing whole-food diets to evaluate the role of dietary factors in cancer prevention.


Assuntos
Anticarcinógenos/farmacologia , Dieta , Glândulas Mamárias Animais/crescimento & desenvolvimento , Neoplasias Mamárias Animais/prevenção & controle , Desenvolvimento Sexual/efeitos dos fármacos , Vitamina A/análogos & derivados , Vitamina A/farmacologia , Animais , Anticarcinógenos/administração & dosagem , Diterpenos , Relação Dose-Resposta a Droga , Feminino , Ratos , Ratos Sprague-Dawley , Ésteres de Retinil , Vitamina A/administração & dosagem , Vitamina A/sangue
11.
Biochim Biophys Acta ; 1740(2): 202-5, 2005 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-15949687

RESUMO

Epidemiological evidence associating the decreased risk of prostate cancer with frequent consumption of tomato products inspired us to conduct a small intervention trial among patients diagnosed with prostate adenocarcinoma. Tomato sauce pasta was consumed daily for 3 weeks before their scheduled prostatectomy, and biomarkers of tomato intake, prostate cancer progression and oxidative DNA damage were followed in blood and the available prostate tissue. The whole food intervention was so well accepted by the subjects that the blood lycopene (the primary carotenoid in tomatoes responsible for their red color) doubled and the prostate lycopene concentration tripled during this short period. Oxidative DNA damage in leukocytes and prostate tissues was significantly diminished, the latter mainly in the tumor cell nuclei, possibly due to the antioxidant properties of lycopene. Quite surprising was the decrease in blood prostate-specific antigen, which was explained by the increase in apoptotic death of prostate cells, especially in carcinoma regions. Prostate cancer cell cultures (LNCaP) were also sensitive to lycopene in growth medium, which caused an increased apoptosis and arrested the cell cycle. A possible explanation of these promising results may reside in lycopene effects on the genes governing the androgen stimulation of prostate growth, cytokines and on the enzymes producing reactive oxygen species, all of which were recently discovered by nutrigenomic techniques. Other phytochemicals in tomato may act in synergy with lycopene to potentiate protective effects and to help in the maintenance of prostate health.


Assuntos
Adenocarcinoma/tratamento farmacológico , Carotenoides/uso terapêutico , Fitoterapia , Preparações de Plantas/uso terapêutico , Próstata/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Solanum lycopersicum , Adenocarcinoma/sangue , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Apoptose/efeitos dos fármacos , Apoptose/genética , Carotenoides/administração & dosagem , Carotenoides/análise , Carotenoides/sangue , Dieta , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Licopeno , Masculino , Preparações de Plantas/administração & dosagem , Próstata/química , Próstata/patologia , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Fatores de Tempo
12.
Cancer Epidemiol Biomarkers Prev ; 13(5): 850-60, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15159319

RESUMO

This report details the findings of a single-dose Phase I pharmacokinetic and toxicity study of a food-based formulation of lycopene in healthy adult male subjects. Five dosing groups (n = 5 per group) were sequentially treated with increasing doses of lycopene ranging from 10 to 120 mg. Blood samples were collected for a total of 28 days (672 h) after administration of single doses of lycopene. The mean time (t(max)) to reach maximum total lycopene concentration (C(max)) ranged from 15.6 to 32.6 h. The C(max) for total lycopene ranged between 4.03 and 11.27 microg/dl (0.075-0.210 microm). Mean AUC(0-96) and elimination half-life for total lycopene ranged from 214 to 655 microg h/dl (3.986-12.201 micromol h/l) and 28.1 and 61.6 h, respectively. The changes observed in lycopene exposure parameters (e.g., C(max) and AUC(0-96)) were not proportional to increments in dose, with larger increases observed at the lowest end of the dosing range (10-30 mg). Chylomicron lycopene was measured during the first 12 h with the differences observed among the dosing groups not reaching statistical significance. These findings may reflect a process of absorption that is saturable at very low dosing levels or may be explained by the large interindividual variability in attained lycopene concentrations that were observed within each dosing group. Pharmacokinetic parameters for trans- and cis-lycopene isomers were calculated and are reported here. The formulation was well tolerated with minimal side effects, which were mainly of gastrointestinal nature and of very low grade.


Assuntos
Antioxidantes/farmacocinética , Carotenoides/farmacocinética , Quilomícrons/sangue , Portadores de Fármacos , Administração Oral , Adolescente , Adulto , Análise de Variância , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Disponibilidade Biológica , Carotenoides/administração & dosagem , Carotenoides/efeitos adversos , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos , Humanos , Licopeno , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Probabilidade
13.
J Pediatr ; 143(5): 644-8, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14615738

RESUMO

OBJECTIVE: To determine whether postnatal vitamin A therapy increased ductal closure rate in premature infants. STUDY DESIGN: This was a prospective, double-blind, placebo-controlled trial. Subjects (n=40) were recruited on day of life 1. Inclusion criteria were premature neonates weighing 500 to 1500 g with an indwelling umbilical line. Vitamin A was administered intramuscularly on days 1, 3, and 7. Blood vitamin A and retinol binding protein levels were obtained on days 1 and 3. Echocardiography was performed on days 1, 3, 7, and 14. Failure of ductal closure was defined as the presence of a moderate to large patent ductus arteriosus on day 14, indomethacin therapy, or surgical ligation. RESULTS: Comparison between the treatment and placebo groups revealed no differences in gestational age, weight, or oxygenation index. Vitamin A and retinol binding protein levels did not differ between the groups at entry but increased significantly after vitamin A treatment. Failure of ductal closure occurred in 22 of 40 babies without any difference between the groups (12/22 vs 10/18, P=NS). Four infants required surgical ligation, all in the treatment group (P=.04). Clinical outcome did not vary between groups. CONCLUSION: Postnatal vitamin A therapy did not improve ductal closure rates in premature infants.


Assuntos
Permeabilidade do Canal Arterial/tratamento farmacológico , Vitamina A/uso terapêutico , Peso ao Nascer , Método Duplo-Cego , Permeabilidade do Canal Arterial/diagnóstico , Eletrocardiografia , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Estudos Prospectivos , Índice de Gravidade de Doença
14.
J Nutr ; 133(9): 2788-92, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12949366

RESUMO

Consumption of lycopene, the predominant carotenoid in tomatoes and tomato products, is associated with reduced prostate cancer risk. The purpose of this study was to measure the pharmacokinetics and tissue distribution of lycopene after oral administration to male dogs. After single doses of 10, 30 and 50 mg/kg body weight (BW) lycopene to 2 dogs/dose, the mean half-life was 36 h and the plasma systemic exposure levels (AUC(0-)( infinity ), area under the curve) after the 30 and 50 mg/kg BW doses were similar. In a repeat dose study, 30 mg/(kg BW. d) administered orally to six dogs for 28 d resulted in steady-state plasma concentrations between 785 and 997 nmol/L lycopene. Apparent clearance, volume of distribution and apparent elimination half-life were 2.29 L/(h. kg), 96 L/kg and 30.5 h, respectively. Dogs were killed 1 or 5 d after the last dose and 23 tissues were collected for lycopene analysis. Lycopene concentrations were highest in liver, adrenals, spleen, lymph nodes and intestinal tissues. Liver lycopene concentrations were 66 and 91 nmol/g 1 and 5 d after cessation of treatment, respectively. Prostate lycopene concentrations were < 0.2 nmol/g both 1 and 5 d after dosing ceased (<0.4% of liver concentrations). Although 70% trans-lycopene was used in the dosing material, most of the lycopene identified in plasma and tissues was cis-lycopene.


Assuntos
Antioxidantes/administração & dosagem , Antioxidantes/farmacocinética , Carotenoides/administração & dosagem , Carotenoides/farmacocinética , Administração Oral , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Carotenoides/sangue , Carotenoides/química , Cães , Licopeno , Masculino , Estereoisomerismo , Distribuição Tecidual
15.
J Lipid Res ; 44(10): 1927-39, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12867539

RESUMO

A physiological pharmacokinetic model was developed to describe the disposition of lycopene, delivered as a tomato beverage formulation in five graded doses (10, 30, 60, 90, or 120 mg), for a phase I study in healthy male subjects (five per dose). Blood was collected before dose administration (0 h) and at scheduled intervals until 672 h. Serum concentrations of carotenoids and vitamins were measured by high performance liquid chromatography analysis. The model was comprised of seven compartments: gastrointestinal tract, enterocytes, chylomicrons, plasma lipoproteins, fast-turnover liver, slow-turnover tissues, and a delay compartment before the enterocytes. As predicted, the percent absorption at the 10 mg dose (33.9 +/- 8.1%) was significantly greater than at the higher doses; however, the amount of lycopene absorbed (mg) was not statistically different (mean: 4.69 +/- 0.55 mg) between doses, suggesting a possible saturation of absorptive mechanisms. The slow-turnover tissue compartment served as a slow-depleting reservoir for lycopene, and the liver represented the fast-turnover pool. Independent of dose, 80% of the subjects absorbed less than 6 mg of lycopene. This may have important implications for planning clinical trials with pharmacological doses of lycopene in cancer control and prevention if absorption saturation occurs at levels that are already being consumed in the population.


Assuntos
Anticarcinógenos/farmacocinética , Antioxidantes/farmacocinética , Carotenoides/farmacocinética , Dieta , Adulto , Anticarcinógenos/sangue , Bebidas , Carotenoides/administração & dosagem , Carotenoides/sangue , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Humanos , Lipídeos/sangue , Fígado/metabolismo , Licopeno , Solanum lycopersicum , Masculino , Pessoa de Meia-Idade , Azeite de Oliva , Óleos de Plantas , Distribuição Tecidual , Vitaminas/administração & dosagem , Vitaminas/sangue , Vitaminas/farmacocinética
16.
J Nutr ; 133(1): 160-6, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12514284

RESUMO

Serum concentrations of several nutrients were measured in 12 captive wild felid species including caracal (Felis caracal), cheetah (Acinonyx jubatus), cougar (Felis concolor), fishing cat (Felis viverrinus), leopard (Panthera pardus), lion (Panthera leo), ocelot (Felis pardalis), pallas cat (Felis manul), sand cat (Felis margarita), serval (Felis serval), snow leopard (Panthera uncia) and tiger (Panthera tigris). Diet information was collected for these animals from each participating zoo (Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens and North Carolina Zoological Park). The nutritional composition of the diets at each institution met the probable dietary requirements for each species except for the pallas cat. Blood samples were collected from each animal (n = 69) and analyzed for lipids (total cholesterol, triacylglycerides, HDL cholesterol and LDL cholesterol), vitamin D metabolites [25-hydroxycholecalciferol (25(OH)D) and 1,25-dihydroxycholecalciferol (1,25(OH)(2)D)], vitamin A (retinol, retinyl stearate and retinyl palmitate), vitamin E (alpha- and gamma-tocopherol) and selected carotenoids. Species differences were found for all except triacylglycerides and 1,25(OH)(2)D. Genus differences were found for retinol, retinyl palmitate, retinyl stearate, gamma-tocopherol and beta-carotene. Circulating nutrient concentrations for many of the species in this study have not been reported previously and most have not been compared with the animals' dietary intakes. The large number of animals analyzed provides a substantial base for comparing the serum nutrient concentrations of healthy animals, for both wild and captive exotic species.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Animais de Zoológico/sangue , Carotenoides/sangue , Lipídeos/sangue , Tocoferóis/sangue , Vitamina A/sangue , Vitamina D/sangue , Animais , Especificidade da Espécie , Vitamina D/metabolismo
17.
J Nutr ; 132(12): 3668-73, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12468605

RESUMO

Age-related macular degeneration (ARMD) is inversely associated with the accumulation of lutein + zeaxanthin in the macula, but higher lutein intakes are inconsistently related to reduced risk of ARMD in epidemiologic studies. Resolution of efficacy awaits clinical trials designed with knowledge of lutein supplement pharmacokinetics. Lutein bioavailability was determined for lutein diester and unesterified lutein formulations as they might be incorporated into dietary supplements. Healthy subjects (n = 18) consumed a single dose of each formulation (either 0.5 or 0.67 micro mol lutein/kg body, 10 and 8 subjects, respectively) in random order, and the appearance of free lutein + zeaxanthin was measured in serum from 0 to 408 h. Areas under the serum concentration x time curves (AUC), as a measure of bioavailability, were independent of gender, body mass index and lutein dose. The lutein diester formulation was 61.6% more bioavailable than the unesterified lutein formulation with higher mean AUC, maximum serum concentration and ascending slope (P < 0.05). The AUC was greater in 14 of 18 subjects when they consumed the lutein diester formulation. Comparison with data from previous studies suggested that dissolution was a greater limitation to bioavailability than lutein ester hydrolysis because an oil-solubilized unesterified lutein preparation, given at 0.5 micro mol/kg body, resulted in greater mean peak concentrations and AUC compared with either the unesterified or lutein diester formulations used in our study. In conclusion, the lutein diester formulation poses no impediment to lutein bioavailability at the doses tested, but formulation dissolution is an important factor in lutein bioavailability and should be evaluated before a supplement and dose are selected for use in clinical trials.


Assuntos
Luteína/farmacocinética , Adulto , Área Sob a Curva , Disponibilidade Biológica , Estudos Cross-Over , Esterificação , Feminino , Humanos , Masculino
18.
Exp Biol Med (Maywood) ; 227(10): 886-93, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12424330

RESUMO

As part of a randomized placebo-controlled study to evaluate the effect of lycopene supplementation on DNA damage in men with prostate cancer, a nonrandomized 5th arm using tomato sauce was included and reported here. Thirty-two patients with localized prostate adenocarcinoma consumed tomato sauce-based pasta dishes for 3 weeks (30 mg of lycopene/day) before their scheduled radical prostatectomy. Prostate tissue was obtained as biopsies at baseline and as resected tissue at the time of the prostatectomy. Serum and prostate lycopene, serum prostate specific antigen (PSA) concentrations, and leukocyte DNA 8-OH-deoxyguanosine/deoxyguanosine (8OHdG) were measured at baseline and at the end of the intervention. Cancer cells in paraffin sections of prostate biopsies and postintervention resected tissue were compared for 8OHdG staining and for apoptosis. Adherence to the daily consumption of tomato-based entrees was 81.6% of the intended dose, and serum and prostate lycopene concentrations increased 1.97- and 2.92-fold (P < 0.001), respectively. Mean serum PSA concentrations decreased by 17.5% (P < 0.002) and leukocyte 8OHdG decreased by 21.3% (P < 0.005) after tomato sauce consumption. Resected tissues from tomato sauce-supplemented patients had 28.3% lower prostate 8OHdG compared with the nonstudy control group (P < 0.03). Cancer cell 8OHdG staining of Gleason Score-matched resected prostate sections was reduced by 40.5% in mean nuclear density (P < 0.005) and by 36.4% in mean area (P < 0.018) compared with the presupplementation biopsy. Apoptotic index was higher in hyperplastic and neoplastic cells in the resected tissue after supplementation. These data taken as a whole indicate significant uptake of lycopene into prostate tissue and a reduction in DNA damage in both leukocyte and prostate tissue. Whether reduction in DNA damage to prostate cancer cells is beneficial awaits further research, although reduction in serum PSA concentrations is promising.


Assuntos
Carotenoides/metabolismo , Desoxiguanosina/análogos & derivados , Neoplasias da Próstata/dietoterapia , Neoplasias da Próstata/metabolismo , Solanum lycopersicum , 8-Hidroxi-2'-Desoxiguanosina , Adenocarcinoma/dietoterapia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Anticarcinógenos/administração & dosagem , Anticarcinógenos/metabolismo , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Apoptose , Carotenoides/administração & dosagem , Desoxiguanosina/metabolismo , Humanos , Licopeno , Masculino , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Nutr Cancer ; 42(1): 78-90, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12235654

RESUMO

We tested the hypothesis that adolescent dietary vitamin A intake impacts mammary gland development and subsequent sensitivity to carcinogenesis. Sprague-Dawley rats were fed a purified diet that was vitamin A deficient, adequate (2.2 mg retinyl palmitate/kg diet), or supranutritional (16 mg retinyl palmitate/kg diet) from 21 to 63 days of age, the period of adolescent mammary gland development. At 73 days of age, rats were given 1-methyl-1-nitrosourea (25 mg/kg body wt i.p.) and monitored for mammary tumors. Tumors appeared earlier and more frequently in rats fed vitamin A-deficient or -supplemented diets. Vitamin A deficiency during adolescence was associated with alveolar mammary gland development and precocious milk protein expression, while supplementation was associated with ductal gland development and suppression of milk protein expression. Differences in circulating estradiol and mammary gland estrogen receptor-alpha, and estrogen-responsive progesterone receptor mRNA were not observed, suggesting that the effects of vitamin A on mammary gland development and carcinogenesis are estrogen independent. Mammary expression of another hormone receptor that regulates milk protein expression, the glucocorticoid receptor, was also unaffected. These results demonstrate that vitamin A intake during adolescence alters mammary gland differentiation and indicate that a narrow range of vitamin A intake during adolescence protects against carcinogenesis.


Assuntos
Neoplasias Mamárias Experimentais/prevenção & controle , Vitamina A/análogos & derivados , Vitamina A/administração & dosagem , Animais , Suscetibilidade a Doenças , Diterpenos , Estradiol/sangue , Receptor alfa de Estrogênio , Proteínas do Leite/genética , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/genética , Receptores de Glucocorticoides/genética , Ésteres de Retinil , Vitamina A/sangue
20.
JPEN J Parenter Enteral Nutr ; 26(3): 189-97, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12005461

RESUMO

BACKGROUND: The purpose of this study was to determine the course of oxidative stress in trauma patients as measured by antioxidant disappearance and modulation of DNA damage. The study also explored the role of injury severity and the effect of changes in plasma lipoprotein concentration as the result of hemodilution on lipid-soluble plasma antioxidant concentrations. METHODS: The study population included 17 adult male trauma patients in an urban level-1 trauma hospital and 12 healthy adult male controls. Blood was collected immediately after admission in the emergency room, and on days 2, 3, 4, 6, and 8 of admission. Plasma antioxidant concentrations and total cholesterol concentrations were evaluated. DNA damage was evaluated using the ratio of 8-hydroxydeoxyguanosine to deoxyguanosine (8OhdG to dG). Admission data were compared with data from controls. RESULTS: Plasma antioxidant concentrations (except alpha-tocopherol) significantly decreased by 9.9% to 34.3% in the 24 hours after trauma and remained depressed throughout day 8. Repeated measures regression analysis for trend showed a significant increase in unadjusted alpha-tocopherol from day 1 to day 8 (p < .008). No other unadjusted antioxidant or plasma cholesterol showed a significant change. After individually adjusting antioxidant concentrations by total cholesterol, only gamma-tocopherol (22.2%) and lycopene (22.6%) were decreased (p < .04) in the 24 hours after trauma. Repeated measures regression analysis for trend for the cholesterol-adjusted antioxidants showed a significant decrease from day 1 to day 8 for cholesterol-adjusted alpha-carotene (p < .007) and beta-carotene (p < .007). Trauma patients were divided into more and less severely injured groups based on Injury Severity Score (ISS). Decreases in antioxidant concentration from day 1 to day 2 were found for the patients in the more injured group, with no significant differences from day 1 to day 2 in the less severely injured group. Cholesterol-adjusted gamma-to copherol (29.7%, p < .003) and lycopene (32.7%, p < .05) decreased from day 1 to day 2 in the more severely injured group. Using repeated measures regression analysis for trend, the only antioxidant that was significantly different in the high versus low ISS groups from day 1 through day 6 was cholesterol-adjusted lutein-zeaxanthin (p < .02). Compared with controls, trauma patients had significantly lower (27.3% to 64.9%) concentrations of all cholesterol-adjusted antioxidants at day 1 except for lycopene. Trauma patients had higher leukocyte 8OhdG to dG ratios at admission (42.6%, p < .05), but 8OhdG to dG ratios tended to decrease over the 24 hours after trauma (p < .07). This decrease was greater in the 3 trauma patients with an admission 8OhdG to dG ratio greater than 6 x 10(-5) (59.3% versus 0.05%, p < .03). CONCLUSIONS: The difference in antioxidant concentrations between trauma patients and controls may have been associated with oxidative stress or with a poorer diet. The difference between antioxidant concentrations and cholesterol-adjusted antioxidant concentrations is likely caused by hemodilution or by changes in plasma lipid levels as a result of trauma. Therefore, individually adjusting lipid-soluble antioxidant concentrations by total cholesterol concentrations is important in trauma patients. Leukocyte 8OhdG to dG ratios were already elevated in trauma patients on admission but returned nearly to control levels 24 hours later, indicating short-term responsiveness to DNA oxidation in trauma patients and an extensive capacity for DNA repair within 24 hours.


Assuntos
Antioxidantes/análise , Colesterol/sangue , Dano ao DNA/fisiologia , Desoxiguanosina/análogos & derivados , Estresse Oxidativo , Ferimentos e Lesões/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Adolescente , Adulto , Antioxidantes/metabolismo , Estudos de Casos e Controles , Reparo do DNA/fisiologia , Desoxiguanosina/sangue , Hemodiluição , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Estudos Prospectivos , Análise de Regressão , Fatores de Tempo , Índices de Gravidade do Trauma , Ferimentos e Lesões/sangue
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