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1.
Oral Dis ; 22(5): 430-7, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26948988

RESUMEN

OBJECTIVES: To relate five periodontopathogenic bacteria, including the red complex, to the severity, extent, and inflammation of the periodontal lesion in Caucasian patients with generalized aggressive and chronic periodontitis and to explore whether tobacco use is associated with a specific bacterial profile. MATERIALS AND METHODS: A cross-sectional and analytic study was conducted in patients with aggressive and chronic periodontitis. Data were gathered on socio-demographic and periodontal variables, and RH-PCR was used to determine subgingival bacterial profile. Linear and logistic regression analyses were performed. RESULTS: The study included 60 patients with aggressive and 123 with chronic periodontitis. Total red complex bacteria count was higher in aggressive periodontitis, mainly due to T. denticola (P = 0.015). In both periodontitis types, models showed an association between T. forsythia count and probing depth (B = 0.157, P = 0.030) and between T. denticola count and higher bleeding scores (B = 2.371, P = 0.027). Smoking did not affect the red complex bacteria count in either disease. CONCLUSIONS: The prevalence of red complex bacteria was similar between aggressive and chronic periodontitis, but their count was higher in the former. In both diseases, T. forsythia was associated with greater severity and T. denticola with more severe bleeding. Tobacco smoking was not associated with the presence of red complex bacteria in either disease.


Asunto(s)
Periodontitis Agresiva/microbiología , Periodontitis Crónica/microbiología , Uso de Tabaco/patología , Treponema denticola/aislamiento & purificación , Infecciones por Treponema/microbiología , Población Blanca , Adulto , Periodontitis Agresiva/etnología , Periodontitis Crónica/etnología , Estudios Transversales , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Femenino , Hemorragia Gingival/microbiología , Humanos , Masculino , Persona de Mediana Edad , Bolsa Periodontal/microbiología , Treponema denticola/genética , Infecciones por Treponema/etnología
2.
J Bioenerg Biomembr ; 47(5): 395-408, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26350412

RESUMEN

Mitochondria are essential for survival. Their primary function is to support aerobic respiration and to provide energy for intracellular metabolic pathways. Paraquat is a redox cycling agent capable of generating reactive oxygen species. The aim of the present study was to evaluate changes in cortical and striatal mitochondrial function in an experimental model of acute paraquat toxicity and to compare if the brain areas and the molecular mechanisms involved were similar to those observed after chronic exposure. Sprague-Dawley rats received paraquat (25 mg/Kg i.p.) or saline and were sacrificed after 24 h. Paraquat treatment decreased complex I and IV activity by 37 and 21 % respectively in striatal mitochondria. Paraquat inhibited striatal state 4 and state 3 KCN-sensitive respiration by 80 % and 62 % respectively, indicating a direct effect on respiratory chain. An increase of 2.2 fold in state 4 and 2.3 fold in state 3 in KCN-insensitive respiration was observed in striatal mitochondria from paraquat animals, suggesting that paraquat redox cycling also consumed oxygen. Paraquat treatment increased hydrogen peroxide production (150 %), TBARS production (42 %) and cardiolipin oxidation/depletion (12 %) in striatal mitochondria. Also, changes in mitochondrial polarization was induced after paraquat treatment. However, no changes were observed in any of these parameters in cortical mitochondria from paraquat treated-animals. These results suggest that paraquat treatment induced a clear striatal mitochondrial dysfunction due to both paraquat redox cycling reactions and impairment of the mitochondrial electron transport, causing oxidative damage. As a consequence, mitochondrial dysfunction could probably lead to alterations in cellular bioenergetics.


Asunto(s)
Cuerpo Estriado/metabolismo , Mitocondrias/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Paraquat/envenenamiento , Animales , Cuerpo Estriado/patología , Proteínas del Complejo de Cadena de Transporte de Electrón/metabolismo , Peróxido de Hidrógeno/metabolismo , Masculino , Mitocondrias/patología , Ratas , Ratas Sprague-Dawley
3.
Phys Rev Lett ; 113(1): 012501, 2014 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-25032921

RESUMEN

The properties of pygmy dipole states in 208Pb were investigated using the 208Pb(17O, 17O'γ) reaction at 340 MeV and measuring the γ decay with high resolution with the AGATA demonstrator array. Cross sections and angular distributions of the emitted γ rays and of the scattered particles were measured. The results are compared with (γ, γ') and (p, p') data. The data analysis with the distorted wave Born approximation approach gives a good description of the elastic scattering and of the inelastic excitation of the 2+ and 3- states. For the dipole transitions a form factor obtained by folding a microscopically calculated transition density was used for the first time. This has allowed us to extract the isoscalar component of the 1- excited states from 4 to 8 MeV.

4.
Actas Urol Esp (Engl Ed) ; 47(1): 27-33, 2023.
Artículo en Inglés, Español | MEDLINE | ID: mdl-36470711

RESUMEN

INTRODUCTION: The objective of this study was to compare the results on prevention of uncomplicated recurrent UTI between continuous use of antibiotics, MV140 autovaccine and MV140 polybacterial vaccine from collection strain. METHODS: 377 patients were prospectively analyzed from January 2017 to August 2019 and divided into 3 groups according to the prophylaxis. Group A (126): antibiotics, Group B (126): MV140 autovaccine, Group C (125): MV140 polybacterial vaccine from the collection strain. Variables analyzed were: gender, age, menopause, number of UTI at baseline and 3 and 6 months after the end of prophylaxis, health cost along follow-up at 3 and 6 months. RESULTS: At 3 months, group A had 0-1 UTI in 65%, group B had 0-1 UTI in 80.8% and group C in 81.7%. At 6 months, group A had 0-1 UTI in 44.4%, group B had 0-1 UTI in 61.6% and group C in 74.6%. Regarding health cost along follow-up, at 3 months group A had euro21,171.87, group B had euro20,763.73 and group C euro18,866.14. At 6 months, health cost was euro32,980.35 in group A, euro28,133.42 in group B, and euro23,629.19 in group C. CONCLUSIONS: MV140 autovaccine and MV140 polybacterial vaccine were more efficient with lower number of UTI at 3 and 6 months and lower health cost along follow-up compared to continued prophylaxis with antibiotics (p < 0.05). Polybacterial MV140 vaccine from collection strain had higher effect to reduce the number of UTI and less health cost than autovaccine.


Asunto(s)
Autovacunas , Infecciones Urinarias , Vacunas , Femenino , Humanos , Lactante , Antibacterianos/uso terapéutico , Autovacunas/uso terapéutico , Infecciones Urinarias/prevención & control , Infecciones Urinarias/tratamiento farmacológico , Vacunas/uso terapéutico , Costos de la Atención en Salud
5.
Endoscopy ; 44(9): 813-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22926666

RESUMEN

BACKGROUND AND STUDY AIMS: Obesity is a risk factor for colorectal neoplasia. Lifestyle modifications, including weight loss, have been advocated to reduce the risk. However, no prospective study has evaluated whether weight loss actually affects adenoma recurrence. The aim of this study was to examine whether weight change (loss or gain) over 4 years is associated with adenoma recurrence. PATIENTS AND METHODS: A total of 1826 patients with colorectal adenoma in the Polyp Prevention Trial had their height and weight measured at baseline. Adenoma recurrence was determined by end of trial colonoscopy 4 years after study entry when patients' weights were re-measured. Poisson regression models were used to evaluate body mass index (BMI), weight change over 4 years, and the risk of any adenoma and advanced adenoma recurrence. RESULTS: Adenoma recurrence was observed in 723 patients (39.6%), 118 (6.5%) of whom had advanced adenoma recurrence. Among those with baseline BMI < 25 kg/m² (n = 466), BMI 25-29 kg/m² (n = 868), and BMI ≥ 30 kg/m² (n = 492), the recurrence rate was 34.5%, 41.0%, and 41.9%, respectively. Obesity was associated with an increased risk of adenoma recurrence (RR = 1.19; 95%CI 1.01-1.39) and advanced adenoma recurrence (RR = 1.62; 95%CI 1.01-2.57). However, when compared with those with relatively stable weight (weight change < 5 lb) over the 4-year trial, weight gain or loss was not associated with adenoma recurrence. This was consistent, regardless of the baseline BMI. CONCLUSIONS: Weight loss or gain over 4 years does not affect adenoma recurrence. This study does not support weight loss alone as an effective intervention for reducing adenoma recurrence.


Asunto(s)
Adenoma/prevención & control , Índice de Masa Corporal , Pólipos del Colon/prevención & control , Neoplasias Colorrectales/prevención & control , Recurrencia Local de Neoplasia/prevención & control , Adenoma/cirugía , Anciano , Pólipos del Colon/cirugía , Neoplasias Colorrectales/cirugía , Grasas de la Dieta/administración & dosificación , Fibras de la Dieta/administración & dosificación , Consejo Dirigido , Femenino , Frutas , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Verduras , Aumento de Peso , Pérdida de Peso
6.
Br J Cancer ; 103(9): 1453-61, 2010 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-20924374

RESUMEN

BACKGROUND: Serum cytokine concentrations may reflect inflammatory processes occurring during the development of colorectal neoplasms. Flavonols, bioactive compounds found in plant-based foods and beverages, may inhibit colorectal neoplasms partly by attenuating inflammation. METHODS: Using logistic regression, we estimated odds ratios (ORs) and 95% confidence intervals (CIs) to investigate the association between serum concentrations of interleukin (IL) ß, 2, 8, 10, 12p70, granulocyte macrophage colony stimulating factor, interferon-γ, and tumour necrosis factor-α, measured over time, flavonol intake, estimated from a flavonol database used in conjunction with a food frequency questionnaire, and adenoma recurrence in 872 participants from the intervention arm of the Polyp Prevention Trial. RESULTS: Decreased IL-2 concentration during the trial increased the risk of any adenoma recurrence (4th vs 1st quartile, OR=1.68, 95% CI=1.13-2.49), whereas decreased IL-1ß or IL-10 reduced the risk of advanced adenoma recurrence (OR=0.37, 95% CI=0.15-0.94; OR=0.39, 95% CI=0.15-0.98, respectively). Individuals with flavonol intake above the median (29.7 mg per day) and decreased cytokine concentrations had the lowest risk of advanced adenoma recurrence. CONCLUSION: Overall, no consistent associations were observed between serum cytokine profile and colorectal adenoma recurrence; however, decreased cytokine concentrations during high flavonol consumption may indicate prevention of colorectal neoplasms.


Asunto(s)
Adenoma/sangre , Adenoma/prevención & control , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/prevención & control , Citocinas/sangre , Flavonoles/administración & dosificación , Anciano , Ensayos Clínicos como Asunto , Dieta , Femenino , Humanos , Interleucinas/sangre , Masculino , Persona de Mediana Edad , Recurrencia
7.
Eur J Clin Nutr ; 62(2): 186-96, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17487212

RESUMEN

OBJECTIVE: To determine the effects of dietary change on serum concentrations of insulin, glucose, IGF-I and IGFBP-3. SUBJECTS: From among participants in a randomized clinical trial of men and women without a history of diabetes who were 35 years old or older and who had at least one histologically confirmed colorectal adenoma removed during a qualifying colonoscopy within the 6 months before randomization, 750 subjects were selected for this analysis. METHODS: The authors analyzed fasting serum from 375 subjects with and 375 subjects without a recurrent polyp among participants in a randomized trial of a low-fat (20% of energy), high-fiber (18 g per 1000 kcals of energy intake) and high-fruit and -vegetable (5-8 servings per day) dietary intervention. RESULTS: After 4 years of follow-up, IGF-I concentration in the intervention group (N=248) declined by 8.86 ng/ml (initial mean of 133 ng/ml) and 7.74 ng/ml (initial mean value of 139 ng/ml) in the non-intervention group (N=502). Based on an unpaired t-test, these declines were both statistically significant, but the difference between groups for the decline in IGF-I (1.12 ng/ml ((95% confidence interval, -3.24 to 5.48)) was not. After 4 years, concentrations of IGFBP-3, insulin and glucose were not statistically different from values at baseline, and there were no differences in these serum measures between the intervention and control groups. In analysis restricted to lean (body mass index <25 kg/m(2)) subjects only, however, glucose concentrations in the intervention group decreased by 0.28 mmol/l, while they increased in the control group by 0.01 mmol/l (t-test for mean differences P=0.0003) over 4 years. CONCLUSIONS: A low-fat, high-fiber, high-fruit and -vegetable dietary intervention had minimal impact on serum concentrations of insulin, glucose, IGF-I and IGFBP-3 overall, but in lean subjects the intervention resulted in a significant reduction in serum glucose concentration.


Asunto(s)
Glucemia/análisis , Dieta con Restricción de Grasas , Fibras de la Dieta/administración & dosificación , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Insulina/sangre , Adenoma/sangre , Adenoma/prevención & control , Glucemia/metabolismo , Índice de Masa Corporal , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/prevención & control , Femenino , Frutas , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Verduras
8.
Actas Urol Esp ; 31(2): 141-5, 2007 Feb.
Artículo en Español | MEDLINE | ID: mdl-17645093

RESUMEN

INTRODUCTION: To evaluate the differences between laparoscopic (LRP) and open radical prostatectomy (ORP). MATERIAL AND METHODS: From 2004 to 2005 180 Radical prostatectomies (RP) were performed, 105 laparoscopical and 75 by an open approach. Different urologists have acted as first surgeon; 51% of them, fully experienced ones in OPR, and 56% in LRP. Differences in operative time, estimated blood loss (difference of pre and post operative hematocrite), and duration of hospitalization were compared. Additionally, we have also analysed surgical and oncologic control of the specimen defined by the following variables: Malignant margins (MM) (positive margin in a pT3 specimen), and benign/malign surgical incision (BSI/MSI). RESULTS: Groups were similar concerning age, clinical stage and Gleason score, and there are only differences in PSA. Mean operative time was significantly higher in LRP (172 minutes) versus ORP (145 minutes) (p < 0.001). Difference of pre and post operative hematocrite was also higher in the open group (10.7 vs 9.2) (p = 0.03), together with hospital stay, which was one day longer in the ORP group (p = 0.001). ORP group had a higher rate of benign surgical incisions (48.7% vs 26.7%) (p = 0.001). Regarding oncologic results, LRP presented a 5.4% of positive margins, which compared significantly with a 16.9% rate in the open group (p = 0.023). However, no differences concerning malignant surgical incisions were observed. CONCLUSION: With no differences in clinical and pathological stage, LRP offers a significant reduction of surgical aggressiveness on the specimen, together with a better MM control. We also observe a clear decrease in blood loss and hospital stay. Therefore, we conclude that LRP in our environment is a valid approach of surgical prostate cancer treatment in spite of a longer operative time (27 minutes) and a steep learning curve.


Asunto(s)
Laparoscopía , Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Anciano , Humanos , Masculino , Estudios Prospectivos
9.
J Natl Cancer Inst ; 79(1): 83-91, 1987 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3037148

RESUMEN

Major food sources of total dietary fiber are presented for the whole U.S. population and by age, sex, and race. Revised data on fiber content were applied to dietary intake data from the Second National Health and Nutrition Examination Survey, a representative sample of the U.S. population examined in 1976-80. Vegetables are the principal sources of dietary fiber, followed by bread and fruit. Legumes are important population sources and rank first for several age-sex-race categories when food groups are broken down into more detailed food items. Breakfast cereals make considerably lesser contributions. Data on fiber intake in several age, sex, and race groups are also presented.


Asunto(s)
Encuestas sobre Dietas , Fibras de la Dieta/análisis , Análisis de los Alimentos , Encuestas Nutricionales , Adulto , Factores de Edad , Anciano , Demografía , Etnicidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Estados Unidos
10.
J Natl Cancer Inst ; 82(8): 650-61, 1990 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-2157027

RESUMEN

Whether colon cancer risk can be modified by a diet rich in vegetables, grains, and fruit, and, if so, whether the protective factor is dietary fiber or other biologically active components correlated with a high-fiber diet are questions of active research interest. Because studies on diet are susceptible to bias from a number of sources, in this review we evaluated the adequacy of study methodology as well as study results to clarify how much protection, if any, is conferred by a high-fiber diet. The review consisted of an aggregate assessment of the strength of evidence from 37 observational epidemiologic studies as well as meta-analyses of data from 16 of the 23 case-control studies. Both types of analyses revealed that the majority of studies gave support for a protective effect associated with fiber-rich diets; an estimated combined odds ratio (OR) of 0.57 (95% confidence interval = 0.50, 0.64) was obtained when the highest and lowest quantiles of intake were compared. Risk estimates based on vegetable consumption (OR = 0.48) were only slightly more convincing than those based on an estimate of fiber intake (OR = 0.58), but the data do not permit discrimination between effects due to fiber and nonfiber effects due to vegetables.


Asunto(s)
Neoplasias del Colon/prevención & control , Fibras de la Dieta/administración & dosificación , Verduras , Estudios de Casos y Controles , Humanos , Metaanálisis como Asunto , Riesgo
11.
J Natl Cancer Inst ; 93(23): 1799-805, 2001 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-11734596

RESUMEN

BACKGROUND: Epidemiologic studies have suggested that estrogen may protect against the development of colorectal cancers and adenomatous polyps. We conducted a prospective study to evaluate the association between hormone replacement therapy (HRT) and adenoma recurrence among perimenopausal and postmenopausal women participating in the Polyp Prevention Trial, a randomized dietary intervention study of individuals with colorectal adenomas. METHODS: We used a questionnaire and interviews to collect detailed information, at baseline and at each of four annual study visits, from 620 women regarding hormone use, menopausal status, diet, alcohol consumption, and other risk factors. Adenoma recurrence was ascertained by complete colonoscopy at baseline and after 1 and 4 years. Logistic regression models were used to evaluate the association between hormone use and adenoma recurrence after adjusting for intervention group and for age and body mass index at baseline. All statistical tests were two-sided. RESULTS: Adenomas recurred in 200 women. There was no overall association between adenoma recurrence and either overall hormone use (odds ratio [OR] = 1.01; 95% confidence interval [CI] = 0.70 to 1.45), combined estrogen and progestin use (OR = 0.94; 95% CI = 0.57 to 1.56), or unopposed estrogen use (OR = 1.04; 95% CI = 0.68 to 1.59). HRT use was associated with a reduction in risk for recurrence of distal adenomas (OR = 0.56; 95% CI = 0.32 to 1.00) and a statistically nonsignificant increase in risk for recurrence of proximal adenomas (OR = 1.39; 95% CI = 0.85 to 2.26). We observed a statistically significant interaction between the HRT-adenoma recurrence association and age (P =.02). HRT was associated with a 40% reduced risk of adenoma recurrence among women older than 62 years (OR = 0.58; 95% CI = 0.35 to 0.97) but with an increased risk among women younger than 62 years (OR = 1.99; 95% CI = 1.11 to 3.55). CONCLUSIONS: HRT was not associated with a reduced risk for overall adenoma recurrence in this trial cohort, although there was a suggestion of an age interaction. The effect of age on the association needs to be confirmed in other adenoma recurrence trials.


Asunto(s)
Adenoma/tratamiento farmacológico , Adenoma/prevención & control , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/prevención & control , Terapia de Reemplazo de Hormonas , Recurrencia , Adenoma/patología , Adulto , Factores de Edad , Anciano , Colonoscopía , Neoplasias Colorrectales/patología , Estrógenos/uso terapéutico , Femenino , Humanos , Menopausia , Persona de Mediana Edad , Oportunidad Relativa , Posmenopausia , Progestinas/uso terapéutico , Análisis de Regresión , Factores de Riesgo , Factores de Tiempo
12.
J Clin Endocrinol Metab ; 81(10): 3599-603, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8855808

RESUMEN

Lipoprotein, apolipoprotein (apo), and hormone levels were measured in 12 healthy women over three consecutive menstrual cycles, one free-living and two under controlled dietary conditions. Serum hormone levels were measured to identify menstrual cycle phases (menses, early follicular, late follicular, and midluteal). After stabilization for one cycle on the controlled diet, ANOVA modeling of the second controlled-diet cycle revealed that low-density lipoprotein (LDL) cholesterol levels in the midluteal phase were significantly lower (by 7%) than in the early follicular phase. High-density lipoprotein (HDL) cholesterol levels during the late follicular phase were higher (by 6%) than menses levels. Differences in the HDL-cholesterol and apoA-I fluctuations resulted in a higher proportion of HDL-cholesterol to apoA-I during the late follicular phase than that during the menses phase. The ratios of LDL cholesterol/HDL cholesterol and apoB/apoA-I in the early follicular phase were greater by 5.6% and 6.0%, respectively, than those in the midluteal phase. Fluctuations in total cholesterol, triglyceride, apoA-I, and apoB did not reach significance. Thus, the cyclic fluctuations of LDL and HDL cholesterol need to be considered in the screening and medical monitoring of women with borderline lipoprotein levels, as well as in the design and the interpretation of results of studies involving premenopausal women.


Asunto(s)
Apolipoproteínas/sangre , Dieta , Lipoproteínas/sangre , Ciclo Menstrual/sangre , Premenopausia/sangre , Adulto , Apolipoproteína A-I/metabolismo , Apolipoproteínas B/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Grasas de la Dieta/administración & dosificación , Estradiol/sangre , Femenino , Humanos , Hormona Luteinizante/sangre , Progesterona/sangre
13.
Am J Clin Nutr ; 48(3 Suppl): 888-95, 1988 09.
Artículo en Inglés | MEDLINE | ID: mdl-3046317

RESUMEN

The National Cancer Institute (NCI) believes that the potential for dietary changes to reduce the risk of cancer is considerable and that the existing scientific data provide evidence that is sufficiently consistent to warrant prudent interim dietary guidelines that will promote good health and reduce the risk of some types of cancer. Six interim dietary guidelines and their scientific rationale are discussed herein. The evidence presented for the scientific rationale is based on the 1982 National Academy of Sciences Committee report Diet, Nutrition and Cancer and NCI's own scientific reviews that link long-term dietary patterns with cancer risk. These guidelines to the American public are consistent with other dietary recommendations from the US departments of Agriculture and Health and Human Services, the American Cancer Society, and the American Heart Association.


Asunto(s)
Dieta/normas , National Institutes of Health (U.S.) , Neoplasias/prevención & control , Humanos , Estados Unidos
14.
Am J Clin Nutr ; 46(5): 790-7, 1987 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2823592

RESUMEN

Twenty-four hour recall data from adults interviewed in the Second National Health and Nutrition Examination Survey, NHANES II, were used as the basis to estimate total dietary fiber intake in the United States. Food fiber values were calculated for the 2500 foods in NHANES II in two ways: 1) using fiber values compiled from the literature by NCI and 2) values based on the Southgate methodology. Mean dietary fiber intake in the US adult population (greater than 19 y of age) is 11.1 g/d using the first set of values and 13.3 g/d according to Southgate values. On a per 1000 kcal basis, women consume more dietary fiber (6.5 g/1000 kcal) than men (5.5 g/1000 kcal) at every age. Fiber intake by geographic region, age, race, and sex is discussed. Our study indicates that dietary fiber intake in the United States is considerably lower than that previously reported.


Asunto(s)
Fibras de la Dieta/análisis , Adulto , Negro o Afroamericano , Factores de Edad , Anciano , Femenino , Humanos , Renta , Masculino , Persona de Mediana Edad , Factores Sexuales , Estados Unidos , Población Blanca
15.
Am J Clin Nutr ; 67(1): 81-7, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9440379

RESUMEN

Because premenopausal women experience cyclic fluctuations of plasma carotenoids and their lipoprotein carriers, it is hypothesized that carotenoid concentrations in lipoprotein fractions fluctuate by phase of the menstrual cycle. Nine women ate a standard set of carotenoid-rich foods daily for two cycles under isoenergetic conditions. In the second cycle, hormones and carotenoids in lipoprotein fractions were measured in the early and late follicular and luteal phases. alpha-Carotene concentrations in the LDL fraction were lower in the early than in the late follicular phase (P = 0.03) on the basis of regression analysis. beta-carotene concentrations in the LDL fraction and the HDL2 subfraction were higher in the late follicular than in the luteal phase (P = 0.02 and P = 0.04, respectively). Lutein/zeaxanthin concentrations in the LDL and HDL fractions were higher in the late follicular than in the luteal phase (P = 0.03 and P = 0.02, respectively). In each phase, 80% of alpha-carotene, 82% of beta-carotene, 85% of lycopene, and 64% of lutein/zeaxanthin were distributed in the LDL fraction. Among the hydrocarbon cartenoids, 18% of alpha-carotene and of beta-carotene and 13% of lycopene were distributed in the HDL fraction, with slightly more in the HDL2 than in the HDL3 subfraction. In contrast 34% of lutein/zeaxanthin was distributed in the HDL fraction with more concentrated in the HDL3 than in the HDL2 subfraction. Less than 4% of any carotenoid was found in the VLDL + IDL (intermediate-density-lipoprotein) fractions. Thus, the hydrocarbon carotenoids were highly concentrated in the LDL fraction and xanthophyll was more evenly distributed in the LDL and HDL fractions. The cyclic fluctuations of these carotenoids in lipoprotein fractions add another dimension to the understanding of their transport and physiologic function.


Asunto(s)
Carotenoides/análisis , Dieta , Lipoproteínas/química , Ciclo Menstrual/fisiología , Adulto , Carotenoides/administración & dosificación , Colesterol/análisis , Dieta/normas , Femenino , Fase Folicular/sangre , Fase Folicular/fisiología , Humanos , Lipoproteínas/sangre , Fase Luteínica/sangre , Fase Luteínica/fisiología , Luteína/administración & dosificación , Luteína/análisis , Licopeno , Ciclo Menstrual/sangre , Xantófilas , Zeaxantinas , beta Caroteno/administración & dosificación , beta Caroteno/análogos & derivados , beta Caroteno/análisis
16.
Am J Clin Nutr ; 65(4 Suppl): 1269S-1274S, 1997 04.
Artículo en Inglés | MEDLINE | ID: mdl-9094932

RESUMEN

Nutrient indexes derived from food-frequency questionnaires have generally been regarded as acceptably valid for epidemiologic purposes. Evaluations of these indexes, however, have considered only their convergent validity. We suggest that discriminant validity, or the ability to distinguish among exposures to different nutrients, is also important. Using baseline data from a large clinical trial, we tested the discriminant validity of indexes of intake of vitamin E, alpha-carotene, and beta-carotene. Our results suggest that the vitamin E index possesses neither convergent not discriminant validity, the alpha-carotene index adequate convergent and discriminant validity, and the beta-carotene index adequate convergent but no discriminant validity.


Asunto(s)
Biomarcadores/sangre , Dieta , Evaluación Nutricional , Carotenoides/administración & dosificación , Carotenoides/sangre , Análisis Discriminante , Alimentos , Humanos , Masculino , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Vitamina E/administración & dosificación , Vitamina E/sangre , beta Caroteno/administración & dosificación , beta Caroteno/sangre
17.
Am J Clin Nutr ; 58(4): 519-24, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8379507

RESUMEN

A newly available carotenoid food-composition database providing specific carotenoid values for > 2300 foods was linked to dietary data on 57 male nonsmokers to examine the association between dietary carotenoid intake and plasma carotenoid concentrations over 3 wk when free-living. Carotenoid intake was estimated from a food-frequency questionnaire (FFQ) and 7 d of food diaries with concurrent analysis of plasma carotenoid concentrations. After adjustment for energy intake, percentage of energy from alcohol, and plasma lipid concentrations, significant diet-plasma correlations for the FFQ and the food diaries (FD) included alpha-carotene (r = 0.29 and 0.43), beta-carotene (r = 0.36 FFQ only), beta-cryptoxanthin (r = 0.46 and 0.44), lutein (r = 0.44 FD only), and lycopene (r = 0.53 FD only). Dietary carotenoid intakes were associated with plasma carotenoid concentrations for all the carotenoids except for beta-carotene when food diaries were used whereas the diet-plasma correlation for the provitamin A carotenoids were consistently significant when the FFQ was used.


Asunto(s)
Carotenoides/administración & dosificación , Carotenoides/sangre , Dieta , Adulto , Bases de Datos Factuales , Registros de Dieta , Análisis de los Alimentos , Humanos , Masculino , Encuestas y Cuestionarios
18.
Am J Clin Nutr ; 64(4): 559-65, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8839500

RESUMEN

This is the first controlled diet study to examine the fluctuation of plasma carotenoids, lipoproteins, and serum hormone concentrations by phase of the menstrual cycle. Nonsmoking, premenopausal women (n = 12) with confirmed ovulatory cycles were given a standard diet with 10 mg total carotenoids/d for two cycles under isoenergetic conditions. Blood was drawn for simultaneous measurement of carotenoids, lipoproteins, and hormones on menses days 1-2, 4-6, 11 through 1 d after the luteinizing hormone surge, and 7-8 d after the surge, representing the menses, early and late follicular, and midluteal phases, respectively. Regression modeling with adjustment for plasma cholesterol concentrations was used to compare mean individual and total plasma carotenoid concentrations by phase of the cycle. Plasma carotenoid concentrations were at their lowest at menses and significantly higher thereafter, except for alpha-carotene. Compared with plasma concentrations at menses, beta-carotene peaked (increased by 9%, P = 0.01) in the late follicular phase. Plasma lutein/zeaxanthin and anhydrolutein concentrations were higher by 8-11% (P < or = 0.006) and by 15-31% (P < or = 0.02), respectively, during the last three phases. Plasma lycopene and phytofluene concentrations peaked (increased by 12%, P = 0.004; and by 21%, P = 0.006, respectively) at the midluteal phase. This cyclic fluctuation may affect the estimation of the plasma carotenoid-disease relation in studies of premenopausal women.


Asunto(s)
Carotenoides/sangre , Dieta , Ciclo Menstrual/sangre , Adulto , Carotenoides/administración & dosificación , Estradiol/sangre , Femenino , Humanos , Lipoproteínas/sangre , Hormona Luteinizante/sangre , Progesterona/sangre
19.
Am J Clin Nutr ; 60(2): 223-30, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8030600

RESUMEN

The diet-plasma relationships for carotenoids were examined in a group of 98 nonsmoking premenopausal women who participated in the cross-sectional phase of the National Cancer Institute (NCI)-US Department of Agriculture (USDA) diet study on alcohol-hormone metabolism, 1988-90. With use of the newly developed USDA-NCI carotenoid food-composition database, the mean daily intakes of carotenoids were significantly higher when estimated from the food-frequency questionnaire (FFQ) than from the 7-d diet records. Lycopene (mean = 0.58 mmol/L), lutein plus zeaxanthin (mean = 0.46 mmol/L), and beta-carotene (mean = 0.34 mmol/L) were the major plasma carotenoids. After adjustment for body mass index, energy and alcohol intakes, and total plasma cholesterol concentration, the following significant correlation (P < 0.05) were observed between the diet record and the FFQ-estimated carotenoid intakes and their respective plasma concentrations: alpha-carotene (r = 0.58 vs 0.49), beta-carotene (r = 0.51 vs 0.49), beta-cryptoxanthin (r = 0.49 vs 0.36), lutein plus zeaxanthin (r = 0.31 vs 0.37), lycopene (r = 0.50 vs 0.26), and total carotenoids (r = 0.57 vs 0.49). These data indicate that plasma carotenoid concentrations are reflective of dietary intake, but the magnitude of the correlation varies depending on the specific carotenoid and on the dietary assessment tool.


Asunto(s)
Carotenoides/administración & dosificación , Carotenoides/sangre , Dieta , Premenopausia/sangre , Adulto , Estudios Transversales , Bases de Datos Factuales , Registros de Dieta , Femenino , Humanos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
20.
Am J Clin Nutr ; 62(1): 131-5, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7598056

RESUMEN

This 6-mo controlled dietary study compared the effect of 30 g alcohol/d for three menstrual cycles with three alcohol-free cycles on plasma carotenoid concentrations in 18 nonsmoking, premenopausal women. Participants were randomly allocated within a crossover design to either phase and consumed approximately 6 mg total carotenoids/d under isoenergetic conditions. Blood was drawn during the third menstrual cycle of each alcohol phase. After adjustment for the mean daily specific carotenoid and energy intakes for each alcohol phase, the paired differences in mean plasma alpha- and beta-carotene concentrations were significantly higher by 19% (P = 0.027) and 13% (P = 0.034), respectively, during the alcohol-intake phase of the study. The paired difference in mean plasma lutein/zeaxanthin concentration was significantly lower by 17% (P = 0.031) when the participants consumed alcohol than when they did not. This is the first reported study in women to document the independent effect of alcohol on plasma carotenoid concentrations without the potential interaction of smoking under controlled dietary conditions.


Asunto(s)
Consumo de Bebidas Alcohólicas/sangre , Carotenoides/sangre , Etanol/farmacología , Premenopausia/sangre , Adulto , Carotenoides/análogos & derivados , Colesterol/sangre , Estudios Cruzados , Femenino , Humanos , Licopeno , Ciclo Menstrual/sangre , Premenopausia/fisiología , Vitamina A/sangre , Vitamina E/sangre , Xantófilas , Zeaxantinas , beta Caroteno
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