Biomedical subjects

P Peer

Publications and source records attributed to P Peer.

At least 19 recordsLinked to original sources

PubMed1990

Information bias in a case-referent study on mental retardation and parental occupation: colleagues as dual respondents.

We conducted a validity study to assess whether information bias from differential misclassification of occupational exposures occurred in a case-referent study on mental retardation and parental occupation. The colleagues of 42 case parents and 38 referent parents were traced and interviewed with a questionnaire similar to that used for the parents. Within each parent-colleague pair, Cohen's kappa coefficient was calculated as a measure of agreement between the reported occupational exposures. Averaged across pairs, the mean kappa coefficient was 0.48 (95% CI = 0.40-0.56) for case pairs and 0.46 (95% CI = 0.38-0.54) for referent pairs, indicating little evidence for differential reporting of exposures between cases and referents. Our results also indicate that colleagues are eligible substitute respondents for information on occupational exposures.

Adult↗

PubMed1987

Tooth loss and remaining occlusion in a Dutch population.

The aim of this study was to gain a better insight into the tooth-loss pattern in terms of frequency, location and impaired occlusion. The sample, stratified according to socio-economic class and age, consisted of 750 subjects. The investigation was done by questionnaire and clinical examination. The non-response was small (15%). With increasing age, more teeth were missing. In the lower socio-economic group more teeth were missing than in the higher socio-economic group. The percentage of totally edentulous persons as well as the percentage of persons with one edentulous jaw increased with age. Also, the percentage of antagonistic tooth contacts declined with increasing age. The following order was found in decreasing contacts: first premolar, second premolar, second molar and first molar. In all strata the percentage of antagonistic contacts in the premolar area was larger than in the molar area.

Adult↗

PubMed1984

The renin-angiotensin-aldosterone system in infancy and childhood in basal conditions and after stimulation.

Plasma renin activity (PRA), aldosterone (PA), sodium and potassium concentration were measured in 107 healthy infants and children under basal conditions of normal diet and recumbency. Urinary aldosterone (UAldo), sodium and potassium were also measured (n = 51). A significant (P less than 0.001) age-related decrease in PRA (r = -0.67), PA (r = -0.67), UAldo (r = -0.56) was observed, with a striking scatter of values especially in infancy. The reninangiotensin-aldosterone system (RAAS) was also studied after stimulation by standardised sodium restriction during 4 days, followed by acute postural change (n = 40). After salt restriction a rise of PRA and UAldo was noted, but a rise in PA could not be demonstrated in children aged 0-6 months. The influence of postural change on the RAAS seems more important in older children. The reported values not only in basal but also in stimulated conditions allow study of the RAAS in diseases such as salt loss and hypertension.

Adolescent↗

PubMed1984

The basal levels of active and inactive plasma renin concentration in infancy and childhood.

Basal plasma renin activity, active and inactive plasma renin concentration were measured in 89 healthy recumbent children aged between 1 week and 16 years. A significant (P less than 0.001) age-related decrease for active (r = -0.60), inactive (r = -0.59) and total renin concentration (r = -0.66) was observed. After correction for the influence of age, active renin concentration correlated with plasma renin activity (r = 0.81), but not with inactive renin concentration (r = 0.18). The proportions of active and inactive renin were not related to age, and the overall percentage of inactive renin was 79%.

Adolescent↗

PubMed1983

Levels of renin, angiotensin I and II, angiotensin-converting enzyme and aldosterone in infancy and childhood.

Basal plasma renin activity (PRA), angiotensin I and II (AI, AII), angiotensin-converting enzyme (ACE) activity and plasma aldosterone (PA) and sodium and potassium concentration were simultaneously measured in 55 healthy recumbent children aged between 1 week and 13 years. A significant (P less than 0.001) age-related decrease for PRA (r = -0.73), AI (r = -0.72), AII (r = -0.51) and PA (r = -0.71) was observed but not for ACE (r = 0.26, P = 0.06). After correction for age the correlation between PRA or PA and AI or AII was still significant (P less than 0.005). The strong correlation between AI and AII in the group as a whole (r = 0.82, P less than 0.001) and also in separate age groups, and an AI to AII ratio which was not different between the various age groups suggest that ACE activity in this age range is not rate-limiting for AII generation.

Adolescent↗

PubMed1983

Influence of the stress of venepuncture on basal levels of plasma renin activity in infants and children.

The influence of venepuncture on plasma renin activity (PRA), cortisol, and serum noradrenaline and adrenaline concentration in infants and children was evaluated by comparing values obtained immediately on insertion of an indwelling intravenous line (venepuncture value) and 5 and 60 minutes later. PRA values 5 min after venepuncture in the total group of infants and children were significantly higher (P less than 0.001) than venepuncture values. There was no significant difference between PRA values at 60 min compared to venepuncture or 5 min values. A well performed venepuncture does not systematically affect the PRA values obtained. A significant difference between values for noradrenaline, adrenaline and cortisol at the various points of time could not be demonstrated. The number of lower values for noradrenaline and adrenaline at 60 min, however, prevailed. The stress of a well performed venepuncture is not an explanation for the greater scatter of basal PRA levels in infants and young children.

Age Factors↗

PubMed1974