RESUMO
The status of thiamin, riboflavin, folate, and vitamins B-6, B-12, C, A, D, and E was investigated in 37 middle-aged and healthy French vegetarians by means of a dietary survey and biochemical studies. Values were compared with those of a group of nonvegetarians. Unsatisfactory intakes of vitamin B-6 were observed: vitamin B-6 intake as a percentage of the French Recommended Dietary Allowances was approximately 66% for vegetarians and approximately 58% for nonvegetarians. Vegetarians had a higher mean intake of thiamin, riboflavin, and vitamins C, A, D, and E than did nonvegetarians. Vegetarians did not have a higher risk rate for a biochemical vitamin deficiency of thiamin, riboflavin, folates, and vitamins B-6, C, A, and E than the nonvegetarians. The percentage of subjects assessed as abnormal by blood vitamin concentrations was higher in vegetarians for vitamin B-12 (serum vitamin B-12) and vitamin D, which indicated a higher risk for a deficiency of vitamins B-12 and D in this group.
Assuntos
Dieta Vegetariana , Ingestão de Energia , Estado Nutricional , Vitaminas/administração & dosagem , Adulto , Feminino , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Necessidades Nutricionais , Vitaminas/sangueRESUMO
This study was conducted to determine the nutritional status with respect to fatty acids of 53 institutionalized elderly subjects (group A). Seven-day food records and biochemical determinations were used. The same protocol was applied to 25 healthy young adults (group B). The 1981 French Recommended Dietary Allowances were used to assess adequacy of intake. Total fat intake was found to be too high in both groups. Higher intakes of animal fats and saturated fatty acids and lower intakes of polyunsaturated fatty acids and linoleic acid were documented in group A than in group B. Elderly subjects exhibited decreased 18:2 omega 6 and 20:4 omega 6 in serum phospholipids and triglycerides. Other indicators of essential fatty acid status in group A differed from group B in the direction of deficiency (double-bond index [DBI], 0.93 +/- 0.01 vs 1.13 +/- 0.04, p less than 0.001; total omega 6, 25.07 +/- 0.46% vs 32.49 +/- 0.89%, p less than 0.001). These findings indicate that institutionalized elderly people are deficient in circulating essential fatty acids, which appears to be caused by both diet and metabolism.
Assuntos
Idoso , Dieta , Ácidos Graxos/sangue , Adulto , Idoso de 80 Anos ou mais , Ésteres do Colesterol/sangue , Ingestão de Energia , Metabolismo Energético , Ácidos Graxos Insaturados/sangue , Feminino , Humanos , Ácido Linoleico , Ácidos Linoleicos/sangue , Masculino , Triglicerídeos/sangueRESUMO
Two experiments examined the contribution of the two catecholamines--epinephrine (EPI) and norepinephrine (NE)--to the control of food intake and body weight gain in male rats during chronic exercise. Urinary excretion of both catecholamines rose significantly and was positively correlated to food intake inhibition (NE, n = 54, r = 0.394, p less than 0.01; EPI, n = 54, r = 0.428, p less than 0.01). Oral ingestion of the non-selective beta-adrenoceptor blocking drug, pindolol, abolished the food intake reduction induced by exercise. Furthermore, rats that were treated with pindolol gained weight at a higher rate than untreated rats. These findings are consistent with the idea that catecholamines contribute to post-exercise inhibition of food intake and reduction of body weight in male rats. However, the exact physiological mechanism of catecholamine-induced decrease in food intake remains to be elucidated.
Assuntos
Ingestão de Alimentos , Metabolismo Energético , Epinefrina/fisiologia , Norepinefrina/fisiologia , Esforço Físico , Animais , Peso Corporal , Masculino , Ratos , Ratos Endogâmicos , Receptores Adrenérgicos/fisiologiaRESUMO
Vitamin B1, B2, B6, C, A, and E status was assessed by combining determination of dietary intake with biochemical indices in 55 young male athletes. When compared with 20 matched sedentary controls, a similar number of individuals with biochemical deficiency was found in both groups for vitamins B1, B6, and E despite a higher mean dietary intake of these three vitamins in young athletes. Markedly reduced levels of pyridoxal 5'-phosphate, the biologically active form of the vitamin B6 compounds, were found in both populations. Supplementation administered for one month improved the vitamin status of the control subjects but not entirely those of the young athletes.
Assuntos
Esportes , Vitaminas/metabolismo , Adulto , Deficiência de Vitaminas/epidemiologia , Inquéritos sobre Dietas , Estudos de Avaliação como Assunto , Humanos , MasculinoRESUMO
Many experimental studies have utilized the activity of dopamine-beta-hydroxylase (DBH) as an index of sympathetic activity, since this enzyme is not submitted to uptake mechanisms or to enzymatic metabolism as are the circulating catecholamines norepinephrine (NE) and epinephrine (E). However, large discrepancies have been found between the results of these studies. The hypothesis which is examined in this study is that these discrepancies might arise from the different intensities in the stimuli utilized. In order to examine this possibility, plasma DBH activity was measured in seven subjects at rest and in three different conditions known to increase sympathetic activity to varying degrees, i.e., during hand-grip, standing, and supra-maximal bicycle exercise. Plasma NE and E concentrations were also measured during these stimuli. The results of this study show that DBH activity increases above resting levels only during supramaximal dynamic exercise, while plasma NE and E concentrations increase during each experimental condition. Furthermore, the increases in NE and E are related to each other and are also related to heart rate when all experimental conditions are considered. On the contrary, the variations in plasma DBH (expressed as a percentage of the resting value) are not related to other sympathetic indices or to heart rate. Since NE and E vary little from subject to subject at rest and increase discretely in response to the various stimuli, these plasma catecholamine concentrations therefore appear to represent the most accurate indices of sympathetic activity.
Assuntos
Dopamina beta-Hidroxilase/sangue , Epinefrina/sangue , Esforço Físico , Frequência Cardíaca , Humanos , Contração Isométrica , Masculino , Norepinefrina/sangueRESUMO
The vitamin B6 status of 60 institutionalised elderly subjects (group A: 31 men, mean age = 77 yr and 29 women, mean age = 84 yr) and 41 healthy young adults (group B or control group: 18 men, mean age = 30 yr and 23 women, mean age = 27 yr) was evaluated using erythrocyte aspartate aminotransferase activity coefficient (alpha EGOT) and plasma pyridoxal phosphate (PLP) level (vitamin B6-deficient subjects = alpha greater than 2.0 and PLP less than 80 nmol/l). The kilocalorie, protein and pyridoxine intakes were also estimated. Regarding calories and protein, the diets may be generally considered satisfactory in respect to the French 1981 RDA. The mean dietary intake of vitamin B6 was less than 2 mg/day in all groups. Ninety per cent of the aged, 80 per cent of females in group B in contrast to 56 per cent of males in group B consumed less than their individual vitamin B6 requirements as determined by a probability method. As the incidence of vitamin B6 biochemical deficiency was much higher in the group A (71% for males and 86% for females) than in the control group (11% for males and 30% for females), it is concluded that the high incidence of biochemical vitamin B6 deficiency noted in the aged appeared more relevant from an altered metabolism of the vitamin than from a too low energy intake. Supplements with high doses of vitamin B6 to aged subjects caused a significant decrease in alpha EGOT and a significant increase in PLP levels.
Assuntos
Envelhecimento , Piridoxina/administração & dosagem , Deficiência de Vitamina B 6/epidemiologia , Adulto , Idoso , Aspartato Aminotransferases/sangue , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Eritrócitos/enzimologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Casas de Saúde , Fosfato de Piridoxal/sangue , Fatores Sexuais , Deficiência de Vitamina B 6/sangueRESUMO
The use of sensitive detectors has enabled the development of high performance liquid chromatography (HPLC) for the dosage of plasma catecholamines (adrenalin, A; noradrenalin, NA and dopamine, DA). Separation of the catecholamines may be done with a pair of ions chromatography on grafted silica or with an exchange of ions chromatography. The quantification is carried out, either by electro-chemical detection (HPLC-ECD), or by fluorometry after catecholamines shunting into trihydroxyindoles compounds (THI). The THI method, more sensitive, does not permit the detection of DA. Plasma levels of A or NA of 30 pg/ml (or 150 fmol/ml) may be measured by HPLC-ECD). The validation of this method as compared with a radioenzymatic method (RA-COMT) permits to imagine that the HPLC-ECD method, which has the advantage of being more economical, less complex and faster than the RA-COMT method, represent a useful tool for the exploration of the adrenergic system clinically as well as in research.
Assuntos
Dopamina/sangue , Epinefrina/sangue , Norepinefrina/sangue , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , HumanosRESUMO
In 3 patients with proved pheochromocytoma, circulating catecholamine concentrations, vanillylmandelic acid and total free catecholamine urinary excretion, dopamine-beta-hydroxylase activities in plasma were measured the day before surgery, during the removal of the tumour and postoperatively. Following the removal of the pheochromocytoma, all these parameters declined with a different rate, possibly related to the half-life proper to each molecule. The results showing a decrease in plasma D beta H activities after the removal of the tumors are in good accordance with most authors. The mechanism and the meaning of catecholamines release from non-innervated tumor-cells remain to be elucidated. By considering these three cases, it does not seem that the evolution of D beta H activity after removal of the tumor is dependent upon the fact that the pheochromocytoma releases preferentially either epinephrine or nephinephrine.
Assuntos
Neoplasias das Glândulas Suprarrenais/enzimologia , Dopamina beta-Hidroxilase/sangue , Feocromocitoma/enzimologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Catecolaminas/sangue , Catecolaminas/urina , Feminino , Humanos , Feocromocitoma/cirurgia , Período Pós-Operatório , Ácido Vanilmandélico/urinaAssuntos
Coração/inervação , Receptores de Droga , Sistema Nervoso Simpático/efeitos dos fármacos , Hormônios Tireóideos/fisiologia , Animais , Calorimetria , Epinefrina/farmacologia , Metabolismo dos Lipídeos , Masculino , Ratos , Simpatolíticos/farmacologia , Simpatomiméticos/farmacologia , TireoidectomiaAssuntos
Coração/inervação , Receptores Adrenérgicos/efeitos dos fármacos , Teofilina/farmacologia , Hormônios Tireóideos/fisiologia , Animais , Interações Medicamentosas , Epinefrina/farmacologia , Humanos , Técnicas In Vitro , Masculino , Consumo de Oxigênio , Perfusão , Ratos , Estimulação Química , TireoidectomiaAssuntos
Glândulas Suprarrenais/fisiologia , Etanol/toxicidade , Mobilização Lipídica/efeitos dos fármacos , Glândula Tireoide/fisiologia , Alcoolismo/fisiopatologia , Animais , Catecolaminas/análise , Ácidos Graxos não Esterificados/análise , Humanos , Metabolismo dos Lipídeos , Masculino , Ratos , Ácido Vanilmandélico/urinaAssuntos
Cafeína/farmacologia , Catecolaminas/sangue , Adulto , Cafeína/metabolismo , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
A dietary survey has been carried out in 5 to 6, 9 to 11 and 14 to 16 years old children of the urban area of Dijon. The method was the 7 day-record with data processing by computer. The results showed that the mean caloric intakes were lower than the recommended allowances, and that the mean values of proteins (14.5%), lipids (40%) and carbohydrates (45.5%) were the same in the various age groups. Iron and calcium intakes were not sufficient in adolescent girls. The part of the breakfast was decreasing with age. Large individual variations were observed among children.
Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Inquéritos sobre Dietas , Inquéritos Nutricionais , Adolescente , Fatores Etários , Criança , Pré-Escolar , Ingestão de Energia , Preferências Alimentares , França , Humanos , População UrbanaRESUMO
During the French 1980 Mount Pabil (7,102 m) Expedition, a study was made of four altitude-acclimatised climbers (age 36.5 +/- 3.6 years; VO2max 50.5 +/- 3.1 ml X kg-1). Intake of various nutrients, body weight, skinfold thicknesses as indices of body composition, and water and nitrogen balances, were recorded before, and during high altitude exposure, and again after the return to low altitude. There was a significant (35-57%) reduction in total caloric intake at high altitude. Body weight decreased progressively, mainly due to a reduction in body fat. The subjects apparently remained in water balance, while the nitrogen balance was always negative during high altitude exposure. The significant nutritional alterations were mainly observed above 6,000 m. They are discussed with respect to changes in feeding patterns and in hormonal status of the climbers accompanying hypoxia and other stressors proper to high altitude.
Assuntos
Altitude , Montanhismo , Distúrbios Nutricionais/etiologia , Adulto , Água Corporal/metabolismo , Peso Corporal , Ingestão de Alimentos , Ingestão de Energia , Humanos , Mobilização Lipídica , Masculino , Nitrogênio/metabolismoRESUMO
The daily intake of vitamin B1, B2, B6, PP, C, A, D and E was investigated in 297 adult subjects, undergoing a check-up examination in a Health Center in Burgundy, by the 7-day self-recorded prospective protocol, to determine the prevalence of vitamin deficiency risks in an area of a West European Country. The daily vitamin intake was lower than the French Recommended Dietary Allowances: RDA (CNERNA, 1981). The intake was between 50 and 80% of RDA for vitamin B1 in 58%, B2 in 24%, B6 in 59%, PP in 43%, C in 21%, A in 8%, D in 0.6%, E in 53% of the female population and for B1 in 40%, B2 in 18.5%, B6 in 59%, PP in 46%, C in 27%, A in 11%, D in 7% and E in 47% of the male population. The daily vitamin intake was less than half of RDA vor vitamin B1 in 11%, B2 in 0.6%, B6 in 33%, PP in 6.3%, C in 4.5%, A in 0.6%, D in 98%, E in 36% in the females and for B1 in 3%, B6 in 8.5%, PP in 3.5%, C in 5%, A in 0.7%, D in 91% and E in 9% in the males. The use of a probability analysis for estimating vitamin deficiencies showed intakes below their own requirement in 37.8% for B1, 18% for B2, 58.6% for B6, 46% for PP, 29% for C, 8.3% for A, 98% for D and 43.4% for E in the males and 62.5% for B1, 20.9% for B2, 86% for B6, 46% for PP, 24% for C, 9.2% for A, 98% for D and 59.7% for E in the females. Significant correlations were found between the daily vitamin intake and the caloric intake for B1 (r = 0.64), B2 (r = 0.46), B6 (r = 0.64) and PP (r = 0.62). The significantly lower caloric intake in females than in males explains a higher proportion of vitamin deficiencies for B1, B2, B6 and PP in this population. The consumption of green vegetables and fresh fruit, and, consequently, vitamin C intake, was higher in females. Although it was not possible to determine to what extent the vitamin intake deficiency contributes to an impaired biochemical vitamin status, the dietary data of this study supply sufficient information to demonstrate high prevalences of deficient vitamin status in France, particularly for B1, B6 and E.
Assuntos
Deficiência de Vitaminas/epidemiologia , Comportamento Alimentar , Adulto , Deficiência de Ácido Ascórbico/epidemiologia , Carboidratos da Dieta , Gorduras na Dieta , Proteínas Alimentares , Ingestão de Energia , Feminino , França , Humanos , Masculino , Pessoa de Meia-Idade , Niacinamida/deficiência , Inquéritos Nutricionais , Fatores Sexuais , Fatores Socioeconômicos , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitaminas do Complexo B/epidemiologia , Deficiência de Vitamina D/epidemiologia , Deficiência de Vitamina E/epidemiologiaRESUMO
An assay method for the determination of pyridoxal 5'-phosphate (PLP) in plasma is presented. The procedure is rapid and requires only a small volume. The method includes PLP-dependent enzymatic decarboxylation of L-tyrosine to tyramine (enzyme used: L-tyrosine apodecarboxylase (EC 4.1.1.25) from Streptococcus faecalis) and measurement of tyramine by high-performance liquid chromatography with electrochemical detection. This technique confers specificity, rapidity, and low-cost measurement. Human plasma PLP from 30 normal healthy adults had a mean value of 65.10 +/- 4.70 nM. Sensitivity of the reaction was 1.3 nM and the coefficient of variation of the method (30 repeated assays of sample with a value of 60 nM) was 1.9%.