Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 66
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Appl Environ Microbiol ; 79(2): 734-7, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23144142

RESUMEN

In a comparison to the widely used Cronobacter rpoB PCR assay, a highly specific multiplexed PCR assay based on cgcA, a diguanylate cyclase gene, that identified all of the targeted six species among 305 Cronobacter isolates was designed. This assay will be a valuable tool for identifying suspected Cronobacter isolates from food-borne investigations.


Asunto(s)
Técnicas Bacteriológicas/métodos , Cronobacter/clasificación , Cronobacter/genética , Proteínas de Escherichia coli/genética , Reacción en Cadena de la Polimerasa Multiplex/métodos , Liasas de Fósforo-Oxígeno/genética , Cronobacter/enzimología , Cronobacter/aislamiento & purificación , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos/diagnóstico , Enfermedades Transmitidas por los Alimentos/microbiología , Sensibilidad y Especificidad
2.
Appl Environ Microbiol ; 77(12): 4017-26, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21531829

RESUMEN

Cronobacter (formerly Enterobacter sakazakii) is a recently defined genus consisting of six species, C. sakazakii, C. malonaticus, C. dublinensis, C. muytjensii, C. turicensis, and Cronobacter genomospecies 1. In this study, MboII restriction fragment length polymorphism (RFLP) patterns of O-antigen gene clusters, located between galF and gnd, were used to identify serotypes in Cronobacter spp. Seven O-antigen RFLP clusters were generated, including three C. sakazakii clusters, previously identified as serotypes O1, O2, and O3. The O-antigen regions of six strains with unique RFLP patterns, including two C. sakazakii strains, two C. malonaticus strains, one C. turicensis strain, and one C. muytjensii strain, revealed three O-antigen gene clusters shared among Cronobacter species. PCR assays were developed, targeting the wzx O-antigen polymerase gene, and used to screen 231 Cronobacter strains to determine the frequency of these newly identified serotypes.


Asunto(s)
Técnicas Bacteriológicas/métodos , Enterobacteriaceae/clasificación , Enterobacteriaceae/genética , Familia de Multigenes , Antígenos O/genética , Reacción en Cadena de la Polimerasa/métodos , Análisis por Conglomerados , Cartilla de ADN/genética , ADN Bacteriano/química , ADN Bacteriano/genética , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/microbiología , Microbiología Ambiental , Microbiología de Alimentos , Datos de Secuencia Molecular , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN
3.
J Clin Invest ; 91(4): 1761-8, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8473516

RESUMEN

A subclinical vitamin K deficiency was induced in 32 healthy subjects (four groups of eight males and females) aged 20-40 and 60-80 yr residing in the Metabolic Research Unit of the Human Nutrition Research Center on Aging at Tufts University. Volunteers were initially fed (4 d) a baseline-period diet containing the recommended daily allowance for vitamin K which is equivalent to 80 micrograms/d of phylloquinone (vitamin K1). During the baseline period various parameters of vitamin K nutritional status were monitored. The baseline period was followed by a 13-d depletion period during which the subjects were fed a very low vitamin K1 diet (approximately 10 micrograms/d). After depletion, the subjects entered a 16-d repletion period (four stages lasting 4 d each) during which time they were repleted with 5, 15, 25, and 45 micrograms of vitamin K1 per day. Vitamin K1 depletion dramatically and significantly decreased plasma vitamin K1 levels (P < 0.0001) in both elderly and young groups to values 13-18% of day 1 (elderly 0.22 nM, young 0.14 nM). Repleting the subjects with up to 45 micrograms of vitamin K1 per day failed, in the case of the young subjects, to bring plasma vitamin K1 levels back into the normal range. Dietary vitamin K1 restriction induced different responses in the urinary excretion of gamma-carboxyglutamic acid between the young and the elderly subjects with values decreasing significantly (P < 0.03) in the young while remaining unchanged in the elderly. The vitamin K1 depletion period had no significant effect on either prothrombin and activated partial thromboplastin times, or Factor VII and protein C (as determined by antigenic and functional assays). By using a monoclonal antibody, decarboxy prothrombin was found to increase slightly but significantly in both groups (P < 0.05) as a consequence of the low vitamin K1 diet. This study clearly shows that a diet low in vitamin K1 can result in a functional subclinical deficiency of vitamin K (decreased urinary gamma-carboxyglutamic acid excretion) without affecting blood coagulation.


Asunto(s)
Deficiencia de Vitamina K/inducido químicamente , Vitamina K/administración & dosificación , Ácido 1-Carboxiglutámico/biosíntesis , Ácido 1-Carboxiglutámico/orina , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Antígenos/análisis , Dieta , Factor VII/inmunología , Factor VII/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Nutricional , Tiempo de Tromboplastina Parcial , Proteína C/inmunología , Proteína C/fisiología , Tiempo de Protrombina , Vitamina K/sangre , Vitamina K/metabolismo
4.
Biochim Biophys Acta ; 1426(1): 43-52, 1999 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-9878685

RESUMEN

Gender differences in relation to vitamin K were investigated in the rat. Hepatic phylloquinone and menaquinone (MK-1 to MK-10) concentrations, gamma-carboxyglutamic acid (Gla) excretion, plasma phylloquinone and percent prothrombin were measured in male and female rats on a chow diet (24.5 ng phylloquinone and 8.8 microgram menadione), and on phylloquinone-deficient and -supplemented purified diets (0.38 and 1400 ng phylloquinone/g, respectively). Mean hepatic phylloquinone concentrations varied with dietary intake and ranged from 6.8+/-9.0 pmol/g in the deficient male, to 171. 1+/-56.9 pmol/g in the supplemented female. Menaquinones accounted for a large proportion of total vitamin K in the liver of males and females with MK-4, MK-6, and MK-10 present in highest concentrations. On the chow and supplemented diets, females had significantly higher MK-4, MK-6, and MK-10 concentrations in their livers (P<0.05). On the phylloquinone-deficient diet (-K1), hepatic phylloquinone, MK-4, and to a lesser extent MK-6 (but not MK-10) were significantly reduced (P<0.05). In the phylloquinone-supplemented male and female groups, which did not receive menadione during the experimental period, MK-4 increased above that in the chow groups suggesting synthesis of MK-4 from phylloquinone which was statistically significant in the female (P<0.01). A significant gender difference (P<0.05) was also observed for urinary Gla excretion with less Gla excreted by the females indicating that females may require less dietary phylloquinone than males of the same body weight.


Asunto(s)
Hígado/metabolismo , Vitamina K 1/metabolismo , Deficiencia de Vitamina K/metabolismo , Vitamina K/farmacología , Ácido 1-Carboxiglutámico/orina , Animales , Cromatografía Líquida de Alta Presión , Dieta , Humanos , Masculino , Protrombina/análisis , Ratas , Ratas Sprague-Dawley , Factores Sexuales , Vitamina K/administración & dosificación , Vitamina K/análogos & derivados , Vitamina K 1/sangre , Vitamina K 1/deficiencia , Vitamina K 2/análogos & derivados
5.
Arch Intern Med ; 150(2): 413-8, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2302017

RESUMEN

In 1981 to 1983, the nutrition and health status of 346 Chinese immigrants in Boston, Mass, aged 60 to 96 years was surveyed and analyzed for cardiovascular risk factors. These elderly Chinese were physically active and seldom obese and consumed a high-carbohydrate (57% of total energy intake), low-fat (24% of total energy intake), low-ascorbic acid (0.62 mmol/d) diet. Current cigarette smoking was common (39%) only in men, while alcoholism was rare in both sexes. Compared with elderly whites, they had lower mean blood pressure and blood levels of total, low-density lipoprotein, and high-density lipoprotein cholesterol, apolipoproteins A-I and B, and ascorbic acid. These characteristics resemble those of the urban population in mainland China, where hemorrhagic stroke is the major cause of cardiovascular mortality.


Asunto(s)
Asiático , Enfermedades Cardiovasculares/etnología , Anciano , Anciano de 80 o más Años , Antropometría , China/etnología , Diabetes Mellitus/etnología , Dieta , Femenino , Humanos , Hipertensión/etnología , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos/epidemiología
6.
Am J Clin Nutr ; 63(4): 566-73, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8599321

RESUMEN

Biochemical indexes for assessing vitamin K nutritional status were evaluated in 263 healthy subjects (127 males, 136 females) aged 18-85 y. The influences of aging (stratified by decade), menopause, and sex were examined. Total, carboxylated, and undercarboxylated osteocalcin concentrations were affected by sex and aging with increases in the sixth decade in women attributed to menopause. Aging effects in the women and sex differences were eliminated when undercarboxylated osteocalcin was expressed as a percentage of the total. Plasma phylloquinone and undercarboxylated prothrombin (PIVKA-II) concentrations varied little with aging with the exception of lower concentrations of phylloquinone in women in their third decade compared with other ages and higher concentrations of PIVKA-II in younger males compared with younger females. Urinary gamma-carboxyglutamic acid (Gla)-creatinine excretion ratios increased significantly with age in both males (r = 0.68, P < 0.001) and females (r = 0.63, P < 0.001) with values 20% higher in the females on average over the entire age span. The undercarboxylated osteocalcin concentration, shown previously to be responsive to depletion and repletion of phylloquinone, was compared with the other indexes to determine its reliability as an indicator of vitamin K nutritional status. This measure appears promising because it correlated with plasma PIVKA-II concentrations (r = 0.27, P < 0.001) and with plasma phylloquinone concentrations (r = -0.35, P < 0.001), whereas the agreement between plasma phylloquinone and PIVKA-II concentrations was not as strong (r = -0.15, P < 0.05).


Asunto(s)
Vitamina K/sangre , Ácido 1-Carboxiglutámico/orina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Boston , Creatinina/orina , Femenino , Humanos , Masculino , Menopausia/sangre , Persona de Mediana Edad , Estado Nutricional , Osteocalcina/sangre , Osteocalcina/metabolismo , Protrombina/análisis , Caracteres Sexuales , Vitamina K 1/sangre
7.
Am J Clin Nutr ; 68(5): 1081-7, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9808226

RESUMEN

BACKGROUND: The putative beneficial effects of an increased consumption of fruit and vegetables have been associated with antioxidant nutrients. However, the effect of fruit and vegetable consumption on the overall antioxidant status in humans is unclear. OBJECTIVE: The objective of this study was to investigate whether a diet rich in fruit and vegetables would affect the antioxidant capacity of human plasma. DESIGN: Thirty-six healthy nonsmokers resided in a metabolic research unit and consumed 2 sets of controlled diets. Diet A contained 10 servings of fruit and vegetables each day for 15 d. Diet B was the same as diet A, except diet B also provided 2 servings of broccoli each day on days 6-10. There was a free-living period of a minimum of 6 wk between the 2 experiments using either diet A or diet B. Fasting plasma antioxidant capacity, measured as oxygen radical absorbance capacity (ORAC), and alpha-tocopherol concentrations were determined on days 1, 6, 11, and 16. RESULTS: The fasting baseline plasma ORAC of these subjects was significantly correlated with their estimated daily intake of total antioxidants from fruit and vegetables during the previous year. Plasma ORAC of these subjects was significantly increased by both diets A and B. This increase in ORAC could not be explained by the increase in the plasma alpha-tocopherol concentration. CONCLUSION: Increased consumption of fruit and vegetables can increase the plasma antioxidant capacity in humans.


Asunto(s)
Envejecimiento/sangre , Antioxidantes/metabolismo , Dieta , Frutas , Verduras , Vitamina E/sangre , Adulto , Anciano , Anciano de 80 o más Años , Antioxidantes/administración & dosificación , Cromanos/administración & dosificación , Femenino , Radicales Libres/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Especies Reactivas de Oxígeno/metabolismo
8.
Am J Clin Nutr ; 51(3): 446-52, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2309650

RESUMEN

Plasma pyridoxal-5'-phosphate (PLP) and erythrocyte aspartate aminotransferase activity coefficients were longitudinally determined in rats. Blood was obtained at weeks 0, 1, 2, 4, 6, 9, and 11 from rats initially aged 3 wk, 3 mo, 12 mo, and 23 mo (weeks 0, 1, 4, 6, and 9 only). The diet groups were ad libitum control (ALC), deficient (DEF), and pair-fed control (PF). Plasma PLP concentrations of controls were highest at 3 mo, intermediate at 3 wk and 12 mo, and lowest at 23 mo. When an additional group of 22-mo-old rats was fed a high-vitamin B-6 diet for 4 wk, their low baseline plasma PLP concentrations did not increase significantly. Plasma PLP decreased significantly within 1 wk and activity coefficients increased significantly by week 4 in all DEF rats. Depletion was most rapid and severe in the youngest DEF rats and least in 12-mo-old DEF rats. Mechanisms for the low plasma PLP control values and resistance to depletion in aged rats remain to be determined.


Asunto(s)
Envejecimiento/metabolismo , Aspartato Aminotransferasas/sangre , Eritrocitos/enzimología , Deficiencia de Vitamina B 6/etiología , Animales , Peso Corporal , Ingestión de Energía , Masculino , Estado Nutricional , Fosfato de Piridoxal/sangre , Piridoxina/sangre , Ratas , Ratas Endogámicas F344 , Deficiencia de Vitamina B 6/enzimología , Deficiencia de Vitamina B 6/metabolismo
9.
Am J Clin Nutr ; 48(1): 152-8, 1988 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3389322

RESUMEN

As part of an exploratory study of nutrition and senile cataract relationships between biochemical markers of nutritional status and senile cataract were examined in 112 subjects aged 40-70 y. Seventy-seven subjects had a cataract in at least one lens. Blood levels were determined for total carotenoids, vitamin A, vitamin D, vitamin E, vitamin C, riboflavin, thiamin, vitamin B-6, zinc, copper, selenium, and magnesium. Subjects were grouped into quintiles for each nutrient. Logistic regression was used to estimate the odds ratios (ORs) for cataract among subjects in the highest quintile and the middle three quintiles relative to subjects in the lowest quintile. ORs were adjusted for age, sex, race, and presence of diabetes. Results suggest that risk of cortical cataract was reduced for subjects in the highest quintile of vitamin D and total carotenoids and that persons with cataract may have lower levels of vitamin C and higher levels of vitamin B-6 and Se.


Asunto(s)
Envejecimiento/sangre , Catarata/sangre , Minerales/sangre , Estado Nutricional , Vitaminas/sangre , Adulto , Anciano , Catarata/etiología , Grasas , Humanos , Persona de Mediana Edad , Análisis de Regresión , Factores de Riesgo , Solubilidad , Agua
10.
Am J Clin Nutr ; 50(1): 100-8, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2750682

RESUMEN

Fasting plasma phylloquinone concentrations were determined by reverse-phase high-performance liquid chromatography in a population of young (n = 131) and elderly (n = 195) human subjects. The distribution of values was non-Gaussian but was converted to Gaussian form after a logarithmic transformation of the data. The normal range derived from the lognormal distribution was 0.29-2.64 nmol/L (geometric means = 0.87 nmol/L, median = 0.86 nmol/L). Young females had significantly decreased plasma phylloquinone concentrations when compared with the elderly females whereas concentrations in young males were slightly higher than those in elderly males. A regression model was constructed and revealed that plasma phylloquinone concentrations were positively correlated with plasma triglycerides and alpha-tocopherol. Although the elderly subjects (means = 1.05 nmol/L) had higher levels of phylloquinone than the young subjects (0.94 nmol/L), when the concentration of phylloquinone in plasma is expressed as nanomoles phylloquinone per millimole of triglyceride, the elderly subjects (0.62 x 10(-6) showed decreased levels for phylloquinone compared with the young subjects (0.82 x 10(-6) (p less than 0.001).


Asunto(s)
Vitamina K 1/sangre , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento , Ayuno , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Nutricional , Factores Sexuales , Triglicéridos/sangre , Vitamina A/sangre , Vitamina E/sangre , Vitamina K/sangre
11.
Am J Clin Nutr ; 48(6): 1436-42, 1988 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3202092

RESUMEN

Vitamin C status and interactions with other nutrients were studied in 677 healthy, noninstitutionalized elderly people aged 60-98 y. Although 6% of the males and 3% of the females showed marginal vitamin C status (plasma ascorbic acid 11 to less than 23 mumol/L), only one person had a plasma ascorbic acid (AA) level less than 11 mumol/L. At all levels of total vitamin C intake, mean plasma AA levels were higher in females than males. Vitamin C supplement use was associated with generally higher blood levels of vitamins B-6, B-12, and E and folate in both sexes and with higher levels of retinol in females. However, after both age and the total dietary intake of the specific nutrient being examined were controlled for, plasma AA levels were significantly correlated only with plasma levels of vitamin E and folate in females.


Asunto(s)
Anciano , Ácido Ascórbico/sangre , Anciano de 80 o más Años , Ácido Ascórbico/administración & dosificación , Femenino , Humanos , Masculino , Estado Nutricional , Piridoxina/sangre , Valores de Referencia , Factores Sexuales , Fumar , Vitamina B 12/sangre , Vitamina E/sangre
12.
Am J Clin Nutr ; 65(3): 779-84, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9062529

RESUMEN

The response of osteocalcin and other biochemical markers of vitamin K status to diets formulated to contain different amounts of phylloquinone was assessed in nine healthy subjects aged 20-33 y. Subjects resided in a metabolic ward for two 15-d cycles with a minimum of 6 wk between cycles. A mixed diet containing 100 micrograms phylloquinone/d was fed throughout both cycles; however, the phylloquinone content of one of the cycles was increased to a total of 420 micrograms/d on days 6 through 10 by fortifying corn oil in the diet with phylloquinone (supplemented diet). Total serum osteocalcin concentrations were not affected by either of the dietary treatments. The percentage of undercarboxylated osteocalcin increased an average of 28% over the 15-d cycle with the mixed diet (P < 0.05) and declined significantly an average of 41% with 5 d of the supplemented diet (day 6: 21.9 +/- 1.3%, day 11: 12.8 +/- 1.1%; P = 0.0001) with a rise after the return to the mixed diet (16.7 +/- 1.3%, P < 0.001). Plasma phylloquinone concentrations increased significantly with supplementation (day 6: 0.95 +/- 0.16 nmol/L, day 11: 1.40 +/- 0.29 nmol/L; P < 0.001) and then rapidly returned to presupplementation concentrations on returning to the mixed diet. Twenty-four-hour ratios of urinary gamma-carboxyglutamic acid to creatinine were unchanged with the supplemented diet; however, excretion declined to 91 +/- 2% of baseline after 10 d on the mixed diet (P = 0.01). These results show that undercarboxylated osteocalcin, plasma phylloquinone, and urinary gamma-carboxyglutamic acid excretion appear to be sensitive measures of vitamin K nutritional status because all of these variables were responsive to changes in dietary intake.


Asunto(s)
Ácido 1-Carboxiglutámico/orina , Antifibrinolíticos/administración & dosificación , Antifibrinolíticos/sangre , Dieta , Osteocalcina/sangre , Vitamina K 1/administración & dosificación , Vitamina K 1/sangre , Vitamina K/fisiología , Adulto , Femenino , Humanos , Masculino , Estado Nutricional , Tiempo de Protrombina
13.
Am J Clin Nutr ; 67(6): 1226-31, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9625097

RESUMEN

The purpose of this study was to characterize the absorption and transport of phylloquinone (vitamin K1) by plasma lipoproteins. Twenty-six healthy subjects (11 men and 15 women) aged 20-78 y received phylloquinone in the amount of either 1.43 or 50 microg/kg body wt orally with a fat-rich meal containing 1.0 g/kg body wt of fat, carbohydrate, and protein and 7.0 mg cholesterol/kg body wt. Blood was obtained at baseline (0 h) and 3, 6, 9, and 12 h after the meal for the measurement of plasma lipid and phylloquinone concentrations in plasma and lipoprotein subfractions. In both groups of subjects, triacylglycerol concentrations peaked after 3 h in plasma and in the triacylglycerol-rich lipoprotein fraction, composed of chylomicrons and VLDLs. Plasma phylloquinone concentrations peaked at 6 h. At baseline and during the postprandial phase, > 53% of plasma phylloquinone was carried by the triacylglycerol-rich lipoprotein fraction. In 9 of the 11 subjects supplemented with 50 microg phylloquinone/kg, plasma lipoproteins were isolated by sequential ultracentrifugation. In these subjects the fraction of plasma phylloquinone carried by LDLs and by HDLs increased progressively from 3% and 4% at 3 h to 14% and 11% at 12 h, respectively. Our data indicate that whereas triacylglycerol-rich lipoproteins are the major carriers of phylloquinone, LDL and HDL may carry small fractions of this vitamin.


Asunto(s)
Antifibrinolíticos/sangre , Antifibrinolíticos/farmacocinética , Grasas de la Dieta/metabolismo , Lipoproteínas/sangre , Vitamina K 1/farmacocinética , Administración Oral , Adulto , Anciano , Antifibrinolíticos/administración & dosificación , Transporte Biológico , Colesterol/sangre , Grasas de la Dieta/administración & dosificación , Femenino , Humanos , Absorción Intestinal , Lipoproteínas/administración & dosificación , Lipoproteínas/fisiología , Masculino , Persona de Mediana Edad , Triglicéridos/sangre , Vitamina K 1/administración & dosificación , Vitamina K 1/sangre
14.
Am J Clin Nutr ; 67(4): 716-21, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9537619

RESUMEN

This randomized, controlled study evaluated the bioavailability of phylloquinone from an intravenous lipid emulsion. A mild vitamin K deficiency was induced in 12 healthy adult men and women by dietary restriction of phylloquinone (40 microg/d, days 1-11) and by administration of warfarin (1.0 mg/d, days 5-11). On day 11, subjects received a 500-mL intravenous solution of either lipid or saline, both of which contained 154 microg phylloquinone. Bioavailability was assessed by serial measurements of plasma phylloquinone, vitamin K1-2,3-epoxide. PIVKA-II (proteins induced by vitamin K absence or antagonists-II), and percentage undercarboxylated osteocalcin. As a result of vitamin K deficiency and minidose warfarin, vitamin K1-2,3-epoxide, PIVKA-II, and percentage undercarboxylated osteocalcin increased significantly between days 1 and 11 (P = 0.05, 0.016, and 0.001, respectively). With the infusions, plasma phylloquinone increased in both groups (P = 0.001). After the infusions vitamin K,-2,3-epoxide decreased in both groups (P = 0.002). Changes in plasma phylloquinone and vitamin K1-2,3-epoxide were no different in the two groups (mean areas under the curves +/- SEM: 116+/-13 nmol x h/L for the saline group and 102+/-20 nmol x h/L for the lipid group for phylloquinone; 38.6+/-7.5 nmol x h/L for the saline group and 31.3+/-9.0 nmol x h/L for the lipid group for vitamin K1-2,3-epoxide). PIVKA-II decreased significantly from baseline values (P = 0.005) in both groups after the infusions. Intravenous lipid reversed the effects of minidose warfarin and of dietary restriction of phylloquinone on hemostasis and vitamin K nutritional status. This reversal was no different from that seen with the infusion of phylloquinone in a saline solution.


Asunto(s)
Biomarcadores , Emulsiones Grasas Intravenosas , Vitamina K 1/farmacocinética , Adulto , Disponibilidad Biológica , Dieta , Femenino , Humanos , Masculino , Osteocalcina/sangre , Precursores de Proteínas/metabolismo , Protrombina/metabolismo , Vitamina K 1/administración & dosificación , Vitamina K 1/análogos & derivados , Vitamina K 1/sangre , Deficiencia de Vitamina K/inducido químicamente , Deficiencia de Vitamina K/metabolismo , Warfarina
15.
Am J Clin Nutr ; 68(3): 699-704, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9734750

RESUMEN

Subjects taking a hydrogen pump blocking agent (omeprazole) develop bacterial overgrowth of the small intestine. We tested the hypothesis that this bacterial overgrowth produces menaquinones, which would meet the vitamin requirement in situations of vitamin K deficiency. In a crossover-type design, 13 healthy volunteers eating a phylloquinone-restricted diet for 35 d were randomly assigned to take omeprazole during the first period of study or starting on day 15 until the end of the study. Coagulation times, serum osteocalcin [total osteocalcin and undercarboxylated osteocalcin (ucOC)], plasma phylloquinone, urinary gamma-carboxyglutamic acid, and plasma undercarboxylated prothrombin (PIVKA-II) were measured. Plasma phylloquinone concentrations declined 82% with dietary phylloquinone restriction (P < 0.05) and were not significantly different in the period when the diet was combined with omeprazole treatment (P > 0.05). The mean value for PIVKA-II during the phylloquinone-restricted diet significantly increased 5.7-fold from baseline (P < 0.05); however, the combination of omeprazole treatment and the phylloquinone-restricted diet significantly reduced PIVKA-II values by 21% (P < 0.05) compared with the diet period alone. There were no alterations in total or percentage ucOC concentrations during the phylloquinone-restricted diet or during the period of diet plus omeprazole treatment. Our data support the hypothesis that bacterial overgrowth results in the synthesis and absorption of menaquinones. These menaquinones contribute to vitamin K nutriture during dietary phylloquinone restriction, but not enough to restore normal vitamin K status.


Asunto(s)
Aclorhidria/metabolismo , Bacterias/crecimiento & desarrollo , Biomarcadores , Intestino Delgado/efectos de los fármacos , Omeprazol/farmacología , Vitamina K 1/farmacología , Deficiencia de Vitamina K/tratamiento farmacológico , Vitamina K/biosíntesis , Ácido 1-Carboxiglutámico/orina , Aclorhidria/inducido químicamente , Aclorhidria/microbiología , Adulto , Anciano , Estudios Cruzados , Dieta , Interacciones Farmacológicas , Humanos , Intestino Delgado/metabolismo , Intestino Delgado/microbiología , Persona de Mediana Edad , Omeprazol/administración & dosificación , Osteocalcina/sangre , Precursores de Proteínas/metabolismo , Protrombina/metabolismo , Vitamina K 1/administración & dosificación , Vitamina K 1/sangre , Deficiencia de Vitamina K/metabolismo
16.
Am J Clin Nutr ; 64(4): 594-602, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8839505

RESUMEN

Plasma carotenoid responses were determined in 36 healthy men and women before and after being fed controlled diets with a moderate amount of fat (26% of total energy) and a high carotenoid content (approximately 16 mg/d) for two 15-d periods. In addition, broccoli (205 g/d) was provided either during the first or the second 15-d residency period in a crossover design. Plasma was digested with lipase and cholesterol esterase, and carotenoids were extracted and measured by using HPLC. Three oxygenated carotenoids (lutein, zeaxanthin, and cryptoxanthin), three hydro-carbon carotenoids (alpha-carotene, all-trans-beta-carotene, and 13-cis-beta-carotene), and four geometric isomers of lycopene (15-cis-, 13-cis-, 9-cis-, and all-trans-lycopene) were separated by using a C30 carotenoid column. A small unidentified peak coeluted with standard 9-cis-beta-carotene and was identified as zeta-carotene (lambda(max) = 400 nm). The concentrations of plasma lutein, cryptoxanthin, alpha-carotene, 13-cis-beta-carotene, all-trans-beta-carotene, and cis- and trans-lycopenes were all significantly increased (P < 0.05) on days 6-16 by the high-fruit and -vegetable diets. The provision of additional broccoli for 5 d to the basic high-carotenoid diet resulted in a further significant increase in the serum concentration of lutein compared with the feeding of the basic high-carotenoid diet alone. Most of the measurable carotenoids of human plasma can be increased by moderate alterations in diet within a short time, although the magnitude of the plasma response may be related to the baseline carotenoid concentrations.


Asunto(s)
Carotenoides/sangre , Dieta , Frutas , Verduras , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/metabolismo , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Am J Clin Nutr ; 57(2): 182-9, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8424386

RESUMEN

We compared the intake of 12 micronutrients as reported on a semiquantitative food frequency questionnaire with corresponding biochemical indicators of nutrient status in a sample of 57 males and 82 females aged 40-83 y. Age-, sex-and energy-adjusted correlation coefficients ranged from near zero for thiamin, vitamin A, and zinc to 0.63 for folate. Correlation coefficients between intake and the biochemical measures were > 0.30 for carotenoids, vitamin D, vitamin E, vitamin B-12, folate, and vitamin C. Differences of 50% or more were observed between extreme quartiles of intake for mean plasma concentrations of folate, vitamin B-12, and vitamin C. Excluding nutrient supplement users generally reduced the correlations. These data demonstrate that food frequency questionnaires can provide valid information on intake for a number of micronutrients.


Asunto(s)
Registros de Dieta , Fenómenos Fisiológicos de la Nutrición , Encuestas y Cuestionarios , Oligoelementos/administración & dosificación , Vitaminas/administración & dosificación , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Oligoelementos/sangre , Vitaminas/sangre
18.
Am J Clin Nutr ; 49(1): 112-20, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2911996

RESUMEN

We studied the relationships of supplemental and total vitamin A and supplemental vitamin E intake with fasting plasma biochemical indicators of vitamin A and vitamin E nutritional status among 562 healthy elderly people (aged 60-98 y) and 194 healthy young adult (aged 19-59 y) volunteers. All subjects were nonsmokers. For the young adults, plasma retinol was significantly greater in males than in females (p less than 0.01); retinol was not related to supplemental vitamin A intake for either group. Fasting plasma retinyl esters demonstrated a significant increase with vitamin A supplement use. For supplemental vitamin A intakes of 5001-10,000 IU/d, a 2.5-fold increase over nonusers in fasting plasma retinyl esters was observed for elderly people (p less than 0.05) and a 1.5-fold increase for young adults (p greater than 0.20). For elderly people, greater fasting plasma retinyl esters were associated with long-term vitamin A supplement use (greater than 5 y) and biochemical evidence of liver damage. Elderly people who take vitamin A supplements may be at increased risk for vitamin A overload.


Asunto(s)
Envejecimiento/sangre , Carotenoides/sangre , Colesterol/sangre , Alimentos Fortificados , Proteínas de Unión al Retinol/sangre , Vitamina A/análogos & derivados , Vitamina A/administración & dosificación , Vitamina A/sangre , Vitamina E/administración & dosificación , Vitamina E/sangre , Anciano , Anciano de 80 o más Años , Diterpenos , Ayuno , Femenino , Humanos , Hipervitaminosis A/sangre , Hipervitaminosis A/etiología , Masculino , Persona de Mediana Edad , Proteínas Plasmáticas de Unión al Retinol , Ésteres de Retinilo
19.
Am J Clin Nutr ; 55(6): 1154-60, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1595588

RESUMEN

The catabolism of homocysteine through cystathionine synthesis requires pyridoxal-5'-phosphate, thus the effect of vitamin B-6 deficiency on plasma homocysteine concentrations was evaluated. Total fasting plasma homocysteine concentrations were measured in 11 elderly subjects aged 64.4 +/- 1.7 y (mean +/- SE) who consumed a vitamin B-6-deficient diet for less than or equal to 20 d. Only 1 of the 11 subjects was found to have elevated homocysteine concentrations even though all subjects exhibited high urinary xanthurenic acid concentrations after a tryptophan load, a measure indicative of vitamin B-6 deficiency. In a supporting study, fasting plasma homocysteine concentrations were measured in 3- and 23-mo-old rats fed vitamin B-6-deficient diets and were compared with those of vitamin B-6-replete, pair-fed controls. There was no difference in homocysteine concentrations between deficient and pair-fed animals after 6 wk of the dietary regimen for either age group; after 9 wk a modest elevation was observed in the 3-mo-old deficient rats whereas no difference was observed for the 23-mo-old rats. It is concluded that fasting plasma homocysteine concentrations are not initially elevated in vitamin B-6 deficiency and therefore fasting plasma homocysteine concentrations are not a good indicator of vitamin B-6 status.


Asunto(s)
Homocisteína/sangre , Deficiencia de Vitamina B 6/sangre , Anciano , Animales , Peso Corporal , Ingestión de Alimentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ratas , Ratas Endogámicas F344 , Triptófano , Xanturenatos/orina
20.
Pediatrics ; 86(6): 883-7, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2251025

RESUMEN

The "superwarfarin" compounds are 4-hydroxy derivatives of coumarin that have increased activity and a longer duration of action than the parent compound. The superwarfarins are used widely in the United States as rodenticides and are effective against warfarin-resistant strains of rats. A chronic accidental ingestion of one of these products, brodifacoum, by a 7-year-old child who had bleeding and laboratory evidence suggestive of a vitamin K-related coagulopathy is reported. The bleeding manifestations were severe and prolonged, requiring 13 months for normalization of coagulation times. With a negative history of ingestion and despite clinical suspicion, documentation of superwarfarin poisoning was hampered by the lack of readily available assays for these compounds, even from the manufacturers. Brodifacoum was also identified in rat feces from the family home. This finding raises the concern of poisoning not only from ingestion of brodifacoum particles themselves, but also from a fecal-oral route. A review of the literature is presented and the implications of this case for the practicing physician are discussed.


Asunto(s)
4-Hidroxicumarinas/envenenamiento , Hemorragia/inducido químicamente , Rodenticidas/envenenamiento , Niño , Femenino , Humanos , Intoxicación/diagnóstico , Intoxicación/terapia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA