European journal of clinical investigation
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Eur. J. Clin. Invest. · Jul 1996
Clinical Trial Controlled Clinical TrialRenal and hormonal actions of atrial natriuretic peptide during angiotensin II or noradrenaline infusion in man.
In order to study the renal and hormonal actions of atrial natriuretic peptide (ANP) during background infusions with angiotensin II (ANG II) or noradrenaline (NA), 69 healthy subjects were examined in three main groups receiving a 90-min infusion with either placebo, ANG II (1.5 ng kg-1 min-1), or NA (25 ng kg-1 min-1). Each of these three main groups were subdivided into two groups receiving an infusion with either placebo or ANP (10 ng kg-1 min-1) for the last 60 min of the background infusion. Lithium clearance was used to evaluate segmental tubular reabsorption. ⋯ It is concluded that the natriuretic action of low-dose ANP seems to be preserved during background infusions with ANG II and NA in man. Net sodium excretion during the combined infusion with ANG II and ANP seems to reflect the sum of the opposing influences of each peptide. Low-dose ANP had a very modest but significant inhibitory effect on proximal tubular sodium reabsorption prestimulated by ANG II infusion.
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Eur. J. Clin. Invest. · Apr 1996
Comparative StudyEffect of regular physical training on age-associated alteration of body composition in men.
Body composition changes with increasing age in men, in that lean body mass decreases whereas fat mass increases. Whether this altered body composition is related to decreasing physical activity or to the known age-associated decrease in growth hormone secretion is uncertain. To address this question, three groups of healthy men (n = 14 in each group), matched for weight, height and body mass index, were investigated using dual-energy X-ray absorptiometry, indirect calorimetry and estimate of daily growth hormone secretion [i.e. plasma insulin-like growth factor I (IGF-I-) levels]. ⋯ Mean plasma IGF-I level in old trained men was higher than in old untrained men (P < 0.05), but was still lower than that observed in young untrained men (P < 0.005) (young untrained men, 236 +/- 24 ng mL-1; old untrained men, 119 +/- 13 ng mL-1; old trained men, 166 +/- 14 ng mL-1). In summary, regular physical training in older men seems to prevent the changes in body composition and fuel metabolism normally associated with ageing. Whether regular physical training in formerly untrained old subjects would result in similar changes awaits further study.
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Eur. J. Clin. Invest. · Apr 1996
Comparative StudyDifferences in phospholipase A2 activity between males and females and Asian Indians and Caucasians.
There is epidemiological evidence that chronic inflammatory diseases occur more frequently in female than in male subjects and prevail differently in various ethnic populations. Phospholipase A2 (PLA2) (group II) plays a key role in many inflammatory reactions by releasing free arachidonic acid, which is a prerequisite for the production of proinflammatory lipid mediators. We therefore, measured PLA2 activity in plasma, serum, leucocytes and lymphocytes in 20 female and 20 male subjects, 10 of each group being of Asian Indian and of Caucasian origin respectively. ⋯ Lymphocytes exhibited lower activities of PLA2 than neutrophils in all four groups of subjects investigated. Females had a tendency towards higher PLA2 activity in both lymphocytes and neutrophils than males. In conclusion the present investigation revealed an ethnic and sex-dependent basal activity of PLA2, a key enzyme in the pathogenesis of chronic inflammatory diseases.
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Eur. J. Clin. Invest. · Mar 1996
Elevated serum neopterin level: its relation to endotoxaemia and sepsis in patients with major burns.
The present study was conducted to determine the relationship between levels of neopterin and endotoxin in the circulation, and whether the neopterin level was related to the development of severe sepsis after extensive burns. This prospective study included 35 patients with burn size greater than 30% (30-98%), and 22 healthy volunteers who served as a comparison group. Neopterin levels increased in most patients on day 3 post-burn, but they were not significantly correlated with the extent of the burn surface (P > 0 center dot 05). ⋯ These results suggest that thermal injury can lead to an elevation of serum neopterin independent of the burn surface area. The initial increase in the neopterin level may be a part of the acute-phase response to tissue injury itself, whereas the endotoxin release in the circulation may be responsible for the continuous induction of neopterin during the late stage. In addition, the presence of a constant high neopterin level is associated with a critical event in the development of severe burn sepsis.