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Using high-performance liquid chromatography and gas chromatography, we reevaluated the 24-h influence of a serotonin- and dopamine-rich diet on platelet serotonin and serotonin, 5-hydroxyindoleacetic acid (5-HIAA), and major catecholamine metabolites in the urine of 15 healthy adults. Although there were significant responses in urinary free serotonin and catecholamine metabolites, their concentrations did not exceed the upper limits of the reference ranges for any of the participants. For urinary 5-HIAA, pronounced effects were observed within 2-4 h. After 6-8 h, results for 11 participants exceeded the upper limit of the reference range. The median recovery of dietary serotonin as urinary 5-HIAA was 20% and subject to a large range (1-50%). There was no significant change in platelet serotonin. We conclude that, using specific analytical methods, no dietary restrictions need be imposed to diagnose catecholamine (metabolite)-producing tumors. For diagnosis of carcinoids on the basis of urinary 5-HIAA it is appropriate to completely abstain from serotonin-containing foods for greater than or equal to 12 h before testing. Platelet serotonin is a more sensitive marker for carcinoids that produce only small amounts of serotonin, and is unaffected by dietary serotonin.  相似文献   
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We correlated arachidonic acid (AA) and docosahexaenoic acid (DHA) status with anthropometric measures and growth rates in a group of low birth weight infants (≤2500 g; gestational ages 30–41 weeks; n = 143). AA and DHA status were measured in erythrocytes (RBC) and plasma cholesterol esters (CE) during days 10 to 42. Infants received preterm formula without long-chain polyunsaturated fatty acids (LCP; n = 81), with LCP (n = 29) or maternal milk (n = 33). RBC AA contents on day 10 were correlated (P < 0.05) with birth weight in breast-fed infants and all formula-fed infants, with on day 10 a standard deviation score (SDS) for weight, length and occipito-frontal circumference in all formula-fed infants, and with on day 10 an SDS for length in breast-fed infants. Brain weight was related to RBC DHA and CE DHA contents on both day 10 and day 42 in formula-fed infants. Of the variances of brain growth parameters on day 42, 21–34% were explained by DHA status on day 42 and protein intake from days 10–42. Conclusion We conclude that parameters of early neonatal AA status are related to intra-uterine rather than to post-natal growth. Parameters of post-natal brain growth are related to RBC DHA and CE DHA contents on day 42, and to dietary protein intake. These results point to the importance of dietary DHA for brain growth in the first 6 post-natal weeks. Received: 23 July 1996 / Received in revised form and accepted: 18 June 1997  相似文献   
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Summary In addition to their usual diet, nine Type 1 (insulin-dependent) diabetic men and ten male control subjects took 20 g d,ga-tocopheryl acetate enriched evening primrose oil (14.45 g 182c,6, 1.73g 183c,6, 400 mg d,-tocopheryl acetate) daily for one week. At start, diabetic patients had more 140, 150 and 18 2c,6, and less 160, 161c,7, 181c,7, 183c,6, 203c,9, 203c,6, 204c,6 and 226c,3 in plasma, erythrocytes and/or platelets. Furthermore, they had lower 161c,7/160, 181c,7/160, and 204c,6/203c,6 ratios and a higher 203c,6/183c,6 ratio. In diabetic patients, -tocopherol levels in erythrocytes were lower, whereas those in plasma were normal. In both groups, oil intake changed fatty acid profiles. Most markedly, 203c,6 increased, whereas the ratios 203c,6/ 183c,6 and 204c,6/203c,6 decreased. 204c,6 increased in control subjects, but not in diabetic patients. Erythrocytes and platelets responded differently in their fatty acid profiles, -tocopherol rose in plasma and, although less for diabetic patients, in erythrocytes. In diabetic patients as well as in control subjects, erythrocyte count, haemoglobin level, mean corpuscular haemoglobin content and concentration increased and glycosylated haemoglobin percentage decreased without an apparent decline in blood glucose levels. Plasma -thromboglobulin and platelet factor 4 decreased, especially in diabetic patients. In conclusion, diabetic patients had abnormal fatty acid patterns, suggesting an impaired 9, 6 and 5 desaturation and an enhanced chainelongation, and had lower erythrocyte a-tocopherol levels; and short-term high dose intake of evening primrose oil increased 203c,6 in both groups, but 204c,6 only in control subjects, gave fatty acid responses which were different for erythrocytes and platelets, enhanced erythropoiesis, and lowered indices of in vivo platelet activation.  相似文献   
5.
The present review addresses the effect of pre- and postnatal supplementation of nutrition with long-chain polyunsaturated fatty acids (LCPUFA) on neurodevelopmental outcome. The few studies which addressed the effect of prenatal LCPUFA status or prenatal LCPUFA supplementation suggest that a better prenatal arachidonic acid (AA) and doxosahexaenoic acid (DHA) status might be related to a better neurodevelopmental outcome until at least 18 months of age. A review of the few randomized controlled trials on formula supplementation with LCPUFA in preterm infants did not provide evidence for a significant beneficial effect of LCPUFA on developmental outcome. A review of the trials on formula supplementation with LCPUFA in term infants revealed that supplementation with LCPUFA, in particularly supplementation with >or=0.30% DHA, has a beneficial effect on neurodevelopmental outcome until 4 months. The studies could not demonstrate a consistent positive effect beyond that age. It was concluded that the relatively subtle effects of LCPUFA supplementation on neurodevelopmental outcome do not only depend on dosage but also on the gestational period during which the nutritional components are supplied: supplementation prior to term seems to have more effect than that after term.  相似文献   
6.
Obesity, and obesity-associated conditions such as hypertension, chronic kidney disease, type 2 diabetes, and cardiovascular disease, are important risk factors for severe Coronavirus disease-2019 (COVID-19). The common denominator is metaflammation, a portmanteau of metabolism and inflammation, which is characterized by chronically elevated levels of leptin and pro-inflammatory cytokines. These induce the “Suppressor Of Cytokine Signaling 1 and 3” (SOCS1/3), which deactivates the leptin receptor and also other SOCS1/3 sensitive cytokine receptors in immune cells, impairing the type I and III interferon early responses. By also upregulating SOCS1/3, Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 adds a significant boost to this. The ensuing consequence is a delayed but over-reactive immune response, characterized by high-grade inflammation (e.g., cytokine storm), endothelial damage, and hypercoagulation, thus leading to severe COVID-19. Superimposing an acute disturbance, such as a SARS-CoV-2 infection, on metaflammation severely tests resilience. In the long run, metaflammation causes the “typical western” conditions associated with metabolic syndrome. Severe COVID-19 and other serious infectious diseases can be added to the list of its short-term consequences. Therefore, preventive measures should include not only vaccination and the well-established actions intended to avoid infection, but also dietary and lifestyle interventions aimed at improving body composition and preventing or reversing metaflammation.  相似文献   
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BACKGROUND: Prevention of coronary heart disease (CHD) in high-risk subjects. OBJECTIVE: To investigate the associations of dietary intake of alpha-linolenic acid (ALA) and linoleic acid (LA) as assessed by food frequency questionnaire and in the plasma cholesteryl ester (CE), with CHD risk factors. DESIGN: Baseline data of a double-blind, randomized placebo-controlled trial. Subjects have hypercholesterolemia (6.0-8.0 mmol/l) and at least two other CHD risk factors (n=266). RESULTS: The reported dietary ALA and LA intakes and the LA/ALA ratio were associated with the contents in the CE (r=0.37, r=0.21, and r=0.42, respectively; P<0.01). In multivariate analysis, CE ALA was inversely associated with diastolic blood pressure (r=-0.13; P<0.05) and positively with serum triacylglycerol (r=0.13; P<0.05), and CE LA was inversely associated with serum triacylglycerol (r=-0.32; P<0.01). The CE LA/ALA ratio was strongly inversely associated with CE ALA (r=-0.95; P<0.01). In the lowest quintile of CE ALA, mean dietary intake was 0.4 energy % ALA (1.2 g/day), 8.4 energy % LA and an LA/ALA ratio of 21, and in the highest quintile 0.6 energy % ALA (1.7 g/day), 6.8 energy % LA and 12 (ratio). In the lowest quintile of CE ALA the diastolic blood pressure was 4 mm Hg lower (P trend<0.05), and the serum triacylglycerol 0.3 mmol/l higher (P trend NS) when compared with the top quintile. CONCLUSIONS: In a CHD high-risk population with LA-rich background diet, these cross-sectional data suggest that replacing LA in the diet by ALA may decrease diastolic blood pressure, and may increase serum triacylglycerol concentration.  相似文献   
9.
A left to right shunt increases myocardial work and is often accompanied by increased catecholamine levels. Because both increased myocardial work and increased catecholamine levels may induce increased fatty acid utilization, which could increase resting myocardial oxygen consumption and therefore unfavorably affect coronary reserve, we studied myocardial uptake of glucose, pyruvate, lactate, beta-OH-butyrate, acetoacetate, FFA, and triglycerides in 12 7-wk-old lambs with aortopulmonary left to right shunts (58 +/- 2% of left ventricular output, mean +/- SEM) and in 10 control lambs 2 wk after surgery. Despite the shunt, systemic blood flow in the shunt lambs was maintained at the same level as in the control lambs. This was accomplished by an increased heart rate and stroke volume. Furthermore, the shunt was accompanied by an increased myocardial oxygen consumption in the shunt lambs (834 +/- 70 versus 528 +/- 43 mumol O2.min-1 x 100 g-1; p less than 0.05). There were no significant differences in arterial substrate concentrations between the two groups. The same was true for arteriovenous differences across the myocardium, with the exception of lactate, which was substantially higher in shunt than in control lambs (72 +/- 25 versus 18 +/- 23 mumol/L; p less than 0.05). As a consequence, myocardial lactate uptake in the shunt lambs was increased 15-fold (18 +/- 6 versus 1 +/- 2 mumol.min-1 x 100 g-1; p less than 0.02), whereas uptake of the other substrates merely paralleled the increased myocardial blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Epidemiological studies indicate a positive relation between iron status and coronary artery disease (CAD) risk The HFE C282Y allele is associated with increased iron status and higher CAD risk. We investigated whether HFE C282Ymight be a CAD risk factor in Cura?ao in a case-control study design. The patient group comprised 42 men and 10 women. Fifty-four men and 30 women without history of CAD served as age and gender matched controls. HFE C282Y genotypes were established using sequence-specific priming polymerase chain reaction. None of the investigated subjects were homozygous for HFE C282Y, whereas 5/52 (9.6%) CAD patients and 1/84 controls (1.2%) were heterozygous for HFE C282Y (p = 0.03). The HFE C282Y mutation was 8.8 fold (95% CI 1.001, 77.8; p = 0.049) more prevalent in CAD patients than in controls. The HFE C282Y allele frequency in Cura?ao is higher than that of African populations, but comparable with that of Jamaica. We conclude that Cura?ao CAD patients have somewhat higher frequency of HFE C282Y heterozygosity than controls, and that the HFE C282Y allele frequency in the Cura?ao population is higher than might be expected in persons of African descent. The consequences of HFE C282Y heterozygosity as CAD risk factor are as yet uncertain, since there is no proof that iron lowering reduces CAD risk.  相似文献   
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