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Biomedical subjects

P A de Jong

Publications and source records attributed to P A de Jong.

At least 19 recordsLinked to original sources
PubMed2006

Bronchiolitis obliterans following lung transplantation: early detection using computed tomographic scanning.

BACKGROUND: Computed tomographic (CT) scanning may enable earlier diagnosis of chronic lung allograft dysfunction than forced expiratory volume in 1 second (FEV1). A study was undertaken to determine intra-observer and inter-observer agreement of composite and air trapping CT scores, to examine the association of FEV1 with the composite and air trapping CT score, and to relate the baseline composite CT score to changes in FEV1 and changes in the composite CT score over 1 year. METHODS: Lung function and baseline CT scans following transplantation and at subsequent annual follow ups were analysed in 38 lung transplant recipients. Scans were randomly scored by two observers for bronchiectasis, mucus plugging, airway wall thickening, consolidation, mosaic pattern, and air trapping, and re-scored after 1 month. CT scores were expressed on a scale of 0-100 and correlated with FEV1 as a percentage of the post-transplant baseline value. RESULTS: The mean (SD) interval between baseline and follow up CT scans was 11.2 (4.7) months. Inter-observer and intra-observer agreement was good for both the composite and air trapping CT scores. There was a significant association between FEV1 and the composite CT score, with each unit of worsening in the baseline composite CT score predicting a 1.55% and 1.37% worsening in FEV1 over the following year (p<0.0001) and a 1.25 and 1.12 unit worsening in the composite CT score (p<0.0001) for observers 1 and 2, respectively. CONCLUSION: These findings indicate a potential role for a composite CT scoring system in the early detection of bronchiolitis obliterans.

Adolescent↗
PubMed2006

Computed tomographic estimation of lung dimensions throughout the growth period.

The aim of the current study was to use computed tomography (CT) to estimate airway wall and lumen, and arterial and parenchyma dimensions in children throughout the growth period, and to provide normative data to study alterations caused by pulmonary disease. Clinical CT scans reported as normal that were performed in children for nonpulmonary and noncardiac reasons were analysed for lung weight, gas volume, lung expansion, lung surface/volume ratio, airway wall area, airway lumen area, airway lumen perimeter, arterial area and airway surface length/area ratio. The age range of the 50 subjects was 0-17.2 yrs. The data showed only little increase in lung expansion throughout childhood (n = 32). There was substantial variability in lung expansion between subjects. Airway wall and lumen and arterial area were exponentially associated with subjects' height (n = 50). Airway surface length/area ratio was linearly associated to alveolar surface/volume ratio. The data from the current study provide normative computed tomography estimates of airway wall and lumen, and arterial and parenchyma dimensions throughout the growth period that may be useful for the study of alterations in disease.

Adolescent↗
PubMed2005

Progression of lung disease on computed tomography and pulmonary function tests in children and adults with cystic fibrosis.

BACKGROUND: A study was undertaken to compare the ability of computed tomographic (CT) scores and pulmonary function tests to detect changes in lung disease in children and adults with cystic fibrosis (CF). METHODS: CT scans and pulmonary function tests were retrospectively studied in a cohort of patients with CF aged 5-52 years for whom two or three CT scans at 3 year intervals were available, together with pulmonary function test results. All CT scans were scored by two observers. Pulmonary function results were expressed as percentage predicted and Z scores. RESULTS: Of 119 patients studied, two CT scans were available in 92 patients and three in 24. CT (composite and component) scores and lung function both deteriorated significantly (p<0.02). Peripheral bronchiectasis worsened by 1.7% per year in children (p<0.0001) and by 1.5% per year in adults (p<0.0001). Bronchiectasis worsened in 68 of 92 patients while forced expiratory volume in 1 second (FEV1) worsened in 54 of 92 patients; bronchiectasis also deteriorated in 27 patients with stable or improving FEV1. The CT score (and its components) and pulmonary function tests showed similar rates of deterioration in adults and children (p>0.09). CONCLUSION: The peripheral bronchiectasis CT score deteriorates faster and more frequently than lung function parameters in children and adults with CF, which indicates that pulmonary function tests and CT scans measure different aspects of CF lung disease. Our data support previous findings that the peripheral bronchiectasis CT score has an added value to pulmonary function tests in monitoring CF lung disease.

Adolescent↗
PubMed2005

Computed tomographic imaging of the airways: relationship to structure and function.

Alterations in the structure of the airways, collectively termed airway remodelling, contribute to airflow obstruction in a variety of chronic lung diseases. While histology has provided valuable insights into the structure of airway wall remodelling, this technique is invasive and does not allow the longitudinal analysis of airway wall dimensions. Technical advances in computed tomography allow the assessment of airway wall dimensions, and are ideally suited for the noninvasive investigation of the pathogenesis of airway wall remodelling and the evaluation of new therapeutic interventions. The aim of this article is to review the use of computed tomography in the investigation of airway structure and function in health and disease.

Airway Obstruction↗
PubMed2004

Carbohydrate solution intake during labour just before the start of the second stage: a double-blind study on metabolic effects and clinical outcome.

OBJECTIVE: To study the effects of oral carbohydrate ingestion on clinical outcome and on maternal and fetal metabolism. DESIGN: Prospective, double-blind, randomised study. SETTING: Leyenburg Hospital, The Hague, The Netherlands. POPULATION: Two hundred and two nulliparous women. METHODS: In labour, at 8 to 10 cm of cervical dilatation, the women were asked to drink a solution containing either 25 g carbohydrates or placebo. In a subgroup of 28 women, metabolic parameters were measured. MAIN OUTCOME MEASURES: Number of instrumental deliveries, fetal and maternal glucose, free fatty acids, lactate, pH, Pco2, base excess/deficit and beta-hydroxybutyrate. RESULTS: Drinking a carbohydrate-enriched solution just before starting the second stage of labour did not reduce instrumental delivery rate (RR 1.1, 95% CI 0.9-1.3). Caesarean section rate was lower in the carbohydrate group, but the difference did not reach statistical significance (1% vs 7%, RR 0.2, 95% CI 0.02-1.2). In the carbohydrate group, maternal free fatty acids decreased and the lactate increased. In the umbilical cord there was a positive venous-arterial lactate difference in the carbohydrate group and a negative one in the placebo group, but the differences in pH and base deficit were comparable. CONCLUSION: Intake of carbohydrates just before the second stage does not reduce instrumental delivery rate. The venous-arterial difference in the umbilical cord suggested lactate transport to the fetal circulation but did not result in fetal acidaemia.

3-Hydroxybutyric Acid↗
PubMed2004

Progressive damage on high resolution computed tomography despite stable lung function in cystic fibrosis.

For effective clinical management of cystic fibrosis (CF) lung disease it is important to closely monitor the start and progression of lung damage. The aim of this study was to investigate the ability of high-resolution computed tomography (HRCT) scoring systems and pulmonary function tests (PFT) to detect changes in lung disease. CF children (n=48) had two HRCT scans in combination with two PFT 2 yrs apart. Their scans were scored using five scoring systems (Castile, Brody, Helbich, Santamaria and Bhalla). "Sensitivity" was defined as the ability to detect disease progression. In this group of children, HRCT scores worsened. PFT remained unchanged or improved. Of the HRCT parameters, mucous plugging and the severity, extent and peripheral extension of bronchiectasis worsened significantly. Relationships between changes in HRCT scores and PFT were weak. Substantial structural lung damage was evident in some children who had normal lung function. These data show that high-resolution computed tomography is more sensitive than pulmonary function tests in the detection of early and progressive lung disease, and suggest that high-resolution computed tomography may be useful in the follow up of cystic fibrosis children and as an outcome measure in studies that aim to reduce lung damage.

Child↗
PubMed2003

Estimation of lung growth using computed tomography.

Anatomical studies suggest that normal lungs grow by rapid alveolar addition until about 2 yrs of age followed by a gradual increase in alveolar dimensions. The aim of this study was to examine the hypothesis that normal lung growth can be monitored by computed tomography (CT). Therefore, the gas volume per gram of lung tissue was estimated from measurements of lung density obtained from CT scans performed on children throughout the growth period. CT scans were performed on 17 males and 18 females, ranging in age from 15 days-17.6 yrs. CT-measured lung weight was correlated with predicted post mortem values and CT measured gas volume with predicted values of functional residual capacity. The median value for lung expansion was 1.86 mL x g(-1) at 15 days, decreased to 0.79 mL x g(-1) by 2 yrs and then increased steadily to 5.07 mL x g(-1) at 17 yrs. Computed tomography scans can be used to estimate lung weight, gas volume and expansion of normal lungs during the growth period. The increase in the lung expansion after the age of 2 yrs suggests progressive alveolar expansion with increasing lung volume.

Adolescent↗
PubMed2001

Eating and drinking in labor: the influence of caregiver advice on women's behavior.

BACKGROUND: Although there is much debate about eating and drinking during labor, little scientific data about its influence on the course of labor exist. In The Netherlands, most midwives and obstetricians allow women to eat and drink during normal labor. The objective of this study was to examine whether or not women were actively advised to eat and drink and if this advice affected eating and drinking behavior. METHODS: A randomly selected group of midwives and obstetricians from across The Netherlands identified 211 consecutive nulliparous women to participate in the study. In a questionnaire with open-ended questions, women were asked after their delivery whether or not they were advised about eating and drinking during labor, and if so, about the nature of this advice and what they had consumed. Data were analyzed at the Leyenburg Hospital in The Hague. RESULTS: Sixty-six percent of the women were not given advice about eating and drinking during labor. Women who were given advice usually followed it. In the total group, 37 percent of the women had intake other than water and of these, 75 percent ate solid food. After adjusting for other prognostic factors, the incidence of an instrumental delivery due to a nonprogressing second stage was lower in women with caloric intake (13% vs 24%, p = 0.04). CONCLUSION: The study design did not enable us to draw conclusions about the cause and effect between caloric intake and labor progress. Scientific data with respect to the giving of evidence-based advice about eating and drinking during labor are lacking. Should such advice become available, women are likely to follow it.

Drinking↗
PubMed2001

Fetal and maternal energy metabolism during labor in relation to the available caloric substrate.

AIM: To discuss maternal and fetal metabolic events during labor and the possible role of glucose administration. RESULTS: The oxidative pathway covers the largest part of the energy demand of labor, although in the second stage or, in polysystolic labor, the non-oxidative pathway becomes important as well. Glucose is the main maternal energy source, but the rise in ketobodies, even during normal labor, suggests a relative shortage. In the first stage of labor, a combination of a respiratory alkalosis, and to a lesser extent, a metabolic acidosis, result in a rise in the maternal pH. In the second stage of labor, the maternal pH decreases due to an increasing metabolic acidosis. Glucose is also the main fetal energetic fuel. In fetal hypoxia, lactate is produced, which in most cases is transferred to the maternal circulation. High maternal lactate concentrations, however, may interfere with this process. Furthermore, fetal hyperglycemia may lead to an increased fetal lactate production. CONCLUSIONS: Maternal hyperglycemia, may lead to an increase in maternal and fetal lactate production resulting in metabolic acidosis. Unlike high dosage intravenous glucose administration, it is not likely that oral intake of carbohydrates leads to maternal and fetal hyperglycemia and subsequently to metabolic acidosis, but studies are rare.

Acid-Base Equilibrium↗
PubMed2000

Angiotensin sensitivity test revisited.

OBJECTIVE: To determine the validity of a single angiotensin sensitivity test as predictor of pregnancy-induced hypertension with special reference to the dietary sodium intake at the time of testing. METHODS: The angiotensin sensitivity test was successfully performed at 32 weeks' gestation in 104 women. In 90 of these women, the 24-h urinary sodium-creatinine ratio was known. Using an effective pressure dose of 10 ng/kg/min as the cutoff level, test characteristics were assessed in both the total population and after subdivision into a sodium restricted (n = 23) and an unrestricted diet group (n = 67). RESULTS: The incidence of pregnancy-induced hypertension was 13.4%. The number of positive angiotensin sensitivity tests was 7.5%. Test characteristics showed poor sensitivity (22.2%) and high specificity (94.8%); positive and negative predictive values were 40.0% and 88.7%, respectively. None of the sodium-restricted women was angiotensin sensitive. Sodium restriction did not have a significant influence on sensitivity, specificity, and predictive values of the test. CONCLUSION: The angiotensin sensitivity test is not an appropriate screening test to predict hypertensive disorders of pregnancy. No significant effect of dietary sodium restriction was found.

Adult↗
PubMed1998

Effect of angiotensin infusion on plasma endothelin in pregnancy.

OBJECTIVE: To study a possible role of plasma endothelin in angiotensin-induced vasoconstriction. STUDY DESIGN: Plasma endothelin levels were measured before and after an angiotensin sensitivity test at 32 gestational weeks in 19 nulliparous women. RESULTS: No significant change in plasma endothelin occurred as a result of angiotensin infusion. CONCLUSION: The angiotensin-induced rise in diastolic blood pressure is not associated with changes in plasma endothelin.

Adult↗
PubMed1996

Diurnal variation in angiotensin sensitivity in pregnancy.

OBJECTIVE: Our purpose was to study the diurnal variation in angiotensin II sensitivity. STUDY DESIGN: Angiotensin sensitivity tests were performed at 9 AM and at 2 PM in 12 normotensive pregnant women, with each woman serving as her own control. RESULTS: In all patients the effective pressor dose was higher in the afternoon. CONCLUSION: We suggest the greater sensitivity to angiotensin in the morning is related to an intrinsic circadian variation in vascular reactivity. When the result of an angiotensin sensitivity test is interpreted, the time of day it is performed should be taken into account.

Angiotensin II↗
PubMed1994

Effects of maternal smoking on neonatal morbidity.

In this paper a prospective study of the association between maternal smoking and neonatal morbidity variables is presented. Caucasian nulliparous women (n = 115) were studied throughout pregnancy, childbirth and puerperal period. Birthweight(-centiles), Apgar scores, mode of delivery, umbilical arterial and venous blood gas analyses, admission incidence to the neonatal ward and the neurological examination according to Prechtl were considered to be representatives for the starting condition of the newborns. The babies of smokers were statistically significantly at a disadvantage compared to babies of non-smokers for birthweight(-centiles), pH of the umbilical vein (medians: smokers 7.29, non-smokers 7.30) and the score of the neurological examination (medians: smokers 57, non-smokers 58).

Apgar Score↗
PubMed1993

Erythrocytic ouabain-sensitive sodium efflux rate constant in pregnancy.

To elucidate the physiology of active sodium transport (expressed as erythrocytic ouabian-sensitive sodium efflux rate constant = ERCos) in pregnancy and the influence of dietary sodium intake on that transport, active sodium transport was measured in 52 healthy pregnant women in week 16, 20, 24, 28, 32, 36 or week 38 of gestation. ERCos was not influenced by parity, dietary sodium intake or the development of pregnancy-induced hypertension. A statistical significant shift in ERCos was detected between week 24 and week 28 of gestation accompanied by a shift in intracellular sodium content. The meaning of this change in pregnancy remains unsolved, but an influence of ANP through A-II is suggested.

Adult↗
PubMed1992

[Loss of taste sensation in terbinafine administration].

Terbinafine is a new antifungal agent for oral treatment of dermatomycosis. Seven patients are reported who developed taste loss after treatment with terbinafine. In four of them, taste loss was complete while one patient was still able to taste sweet products, and a second and third patient no longer tasted salty and sweet products, respectively. In all patients, the onset of the adverse reaction occurred 4-8 weeks after starting treatment. As far as known, taste loss is a transient effect which disappears within 3-6 weeks after discontinuation of terbinafine.

Adult↗
PubMed1991

Assessment of tobacco-exposure during pregnancy; behavioural and biochemical changes.

Smoking-behavior during pregnancy and the reliability of an interview were prospectively investigated. The tobacco-exposure was assessed a) by an intake interview b) by a smoking diary and c) by maternal thiocyanate and carboxy-hemoglobin concentrations. Of the 115 nulliparous women, 66 smoked (57.4%). Seventeen women (25.8%) quit and 39 women (59.1%) reduced smoking. Directly after intake, in the first week of the diary, significantly more cigarettes were smoked than stated during the intake interview. According to the diaries, the number of cigarettes increased during the first half of pregnancy. In the 24th week significantly more cigarettes were smoked than in the first week after intake. Also a significant increase of thiocyanate between the measurements at intake and in the 24th of amenorrhea was found. The maternal carboxy-hemoglobin levels did not significantly change during pregnancy. Investigators should be aware of changes in smoking behavior during pregnancy and the potential bias of self reported smoking behavior at the beginning of pregnancy. The tobacco-exposure should be assessed (anamnestic or biochemical) several times during pregnancy, anyway it should include the second half of pregnancy.

Adult↗
PubMed1991

Effects of angiotensin II on atrial natriuretic peptide in pregnancy.

To clarify the effects on angiotensin II and blood pressure on plasma atrial natriuretic peptide in pregnancy, angiotensin II was infused in 37 healthy, normotensive pregnant women in week 32 of gestation. Levels of atrial natriuretic peptide were determined with the women in a sitting position 3 days before the test and in the left lateral recumbent position immediately before and after the test. Levels of atrial natriuretic peptide were not influenced by parity or salt intake. They were found to be significantly higher in the left lateral recumbent position than in the sitting position. There was also a significant increase in atrial natriuretic peptide levels during angiotensin II infusion. A dose of angiotensin II less than 1.5 ng/kg/min did not affect atrial natriuretic peptide levels. Rise in atrial natriuretic peptide levels was minimally correlated with rise in mean arterial pressure, as caused by acute vasoconstriction from angiotensin II infusion. Therefore it is suggested that, in pregnancy, the response of atrial natriuretic peptide to angiotensin II is mediated not only by changes in blood pressure but also by angiotensinergic receptor activity in the atria.

Adult↗