Search PubMed⌕ Search

Biomedical subjects

A Albert

Publications and source records attributed to A Albert.

At least 181 records · Page 10Linked to original sources
PubMed1990

Combined diagnostic value of biochemical markers in acute pancreatitis.

Eighty-three patients suffering from upper abdominal pain were studied to evaluate the contribution of commonly used biochemical markers in the diagnosis of acute pancreatitis. On admission to hospital, serum amylase, lipase, total bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and gamma-glutamyl transferase activities were measured. By stepwise logistic discrimination, only two determinations appeared to be of clinical value: lipase and alkaline phosphatase activities. A classification rule was established including these two measurements and its diagnostic performance evaluated by a jackknifed method amounted .83%. ROC curves were used to assess sensitivity and specificity. Our study clearly shows that serum lipase measurements should be preferred to amylase measurements, and that our two-test classification rule provides an efficient aid in clinical decision-making.

Acute Disease↗
PubMed1990

Dual photon absorptiometry of lumbar spine in west European (Belgian) postmenopausal females: normal range and fracture threshold.

Bone mineral content (BMC) and bone mineral density (BMD) of lumbar spine have been measured in 695 healthy postmenopausal and 64 type I osteoporotic Belgian, Caucasian females. Bone loss is strongly correlated to time elapse from menopause (Tm) with a maximum rate of bone loss during the first five years of menopause. BMC (gHA) = 461 + 0.662 ln Tm -0.481 (ln Tm)2 and BMD (gHA/cm2) = 0.91 + 0.00711 ln Tm - 0.00846 (ln Tm)2 (in both cases p less than 0.001 and Tm expressed in months of menopause). After 20 years of menopause, 50 to 60% of normal women have vertebral BMC and BMD values below the 90th percentile of women with vertebral fractures and, thus, might be considered to have asymptomatic osteoporosis. We conclude that prevention of postmenopausal osteoporosis should be initiated as soon as possible after the onset of menopause and that bone density screening should be extended in elderly in order to detect and allow treatment of asymptomatic "densitometric" osteoporosis.

Absorptiometry, Photon↗
PubMed1990

Calcitonin and postmenopausal bone loss.

In order to establish the role of calcitonin (CT) in postmenopausal bone loss, we studied CT metabolism in 25 pre- and postmenopausal women. Postmenopausal women presented a highly significant reduction of CT basal levels compared to premenopausal females (p less than 0.01). Also, production rates of CT in osteoporotics were significantly lower than in either young premenopausal (18-25 years old), older premenopausal (35-40 years old), or postmenopausal healthy subjects. In a study in rabbits, we found that injection of CT, along with equimolar amounts of anti-SCT antibodies extracted from serum of pagetic patients, did not inhibit the hypocalcemic response to the hormone, thus demonstrating that resistance to CT treatment cannot be accounted for by antibody production. In a subsequent clinical study in patients with Paget's disease of bone, we found that 200 IU/day of salmon CT (SCT), given by nasal spray, improved both clinically and biochemically the activity of the disease, as demonstrated by 37 +/- 4% decrease of serum alkaline phosphatase and 35 +/- 5% fall of urinary excretion of hydroxyproline after six months of therapy. The effectiveness of CT as nasal spray was further tested in healthy women at an early stage of menopause. A 12-month course of intranasal SCT counteracted early postmenopausal bone loss, presumably by inhibiting bone resorption. In conclusion, intranasal CT seems to be a very attractive alternative to be considered for the prevention of postmenopausal osteoporosis.

Administration, Intranasal↗
PubMed1990

[Mixed venous versus central venous oxygen saturation in intensive medicine].

Mixed venous oxygen saturation (SvO2) has been established as a useful guide in observing whole body oxygenation. Since SvO2 provides limited information about adequate tissue oxygenation for a specific organ, the usefulness of central venous saturation (ScvO2) as a guide was analysed, which is a less invasive parameter. In 19 ICU patients 44 pairs of blood samples were drawn from a separate central venous catheter and from the tip of an SG-catheter. The correlation of oxygen partial pressures was 0.687 and the correlation of the saturation reached 0.779. The calculation of venous admixture showed a correlation of 0.901. It is concluded that ScvO2 yields adequate information on the oxygen saturation of venous return.

Catheterization, Central Venous↗
PubMed1990

[Clinical experiences with central venous multi-lumen catheters].

We retrospectively studied 617 insertions of multilumen-catheters in 570 cardiosurgical patients. Number of catheters, insertion technique, indwelling period, catheter insertion site, specific positions and complications of insertion were evaluated by anesthetic chart and chest x-ray. In most cases the catheters were placed by a percutaneous insertion lock in the right or left v. jugularis interna as main site. Early complications mainly occurred because of incorrect placements. Post-operative radiological control by chest x-ray nearly showed 67% malpositions mainly resulting from the catheter placed not sufficiently far within the insertion lock. Though the catheter initially was placed correctly, it slided back to the insertion lock under mechanical influence on the site of fixation. In only 3 of 617 cases we found a too far inserted catheter. In these cases insertion was made by a Seldinger guidewire after direct venipuncture.

Adult↗
PubMed1989

Characteristics associated with early (less than or equal to 3 months) versus late (greater than 3 months to less than or equal to 3 years) mortality after acute myocardial infarction.

To define the independent variables predictive of early versus late mortality after acute myocardial infarction (AMI), 420 consecutive patients were studied and divided into 3 groups: the 45 patients who died within the initial 3 months (group 1), the 45 patients who died greater than 3 months and less than or equal to 3 years after AMI (group 2) and the 330 greater than 3-year survivors (group 3). The stepwise logistic discrimination method was applied to clinical and laboratory variables recorded during hospitalization to distinguish among the 3 groups. Six independent variables were found to be predictive of early mortality: left ventricular function score (chi-square 26.2; p less than 0.00001), ventricular fibrillation (chi-square 9.3; p = 0.002), bundle branch block (chi-square 9.0; p = 0.003), history of previous AMI (chi-square 8.7; p = 0.003), age (chi-square 5.8; p = 0.02) and atrioventricular block (chi-square 3.8; p = 0.05). Three independent variables were found predictive of late mortality: age (chi-square 13.8; p = 0.0002), anterior location of the AMI (chi-square 4.0; p = 0.04) and a low peak creatine kinase-MB level (chi-square 3.8; p = 0.05). Only 2 variables were able to distinguish between early and late nonsurvivors: peak creatine kinase-MB level (chi-square 8.7; p = 0.003) and ventricular fibrillation (chi-square 4.6; p = 0.03). Thus, the sets of independent risk factors for early and late mortality after AMI are substantially different--suggesting that differing mechanisms are responsible for outcome.

Age Factors↗
PubMed1989

Prognostic significance of a low peak serum creatine kinase level in acute myocardial infarction.

To assess the prognostic significance of a low peak creatine kinase (CK) level, 723 consecutive patients admitted with acute myocardial infarction (AMI) within 16 hours after onset of symptoms were studied. Thrombolytic therapy was not attempted during the study. Patients were dichotomized according to their peak CK levels, determined from a cluster analysis of peak CK distribution among the population of patients who died within 3 years after hospital discharge. The 139 patients with low peak CK (less than or equal to 650 IU/liter) (group 1) were compared to the 584 patients with high peak CK (greater than 650 IU/liter) (group 2). Patients in group 1 were older and had a higher incidence of previous AMI, angina pectoris before AMI and non-Q-wave AMI. Despite a lower incidence of in-hospital complications and a nonsignificantly lower hospital mortality rate (4 vs 9%) the group 1 three-year posthospital mortality rate was higher (26 vs 17%; p less than 0.02), especially in the subgroup of patients with a Q-wave infarct (mortality 31% in group 1 vs 16% in group 2; p less than 0.001). Among the 491 patients who had a first Q-wave AMI, 55 had a peak CK less than or equal to 650 IU/liter. Compared to the 436 patients with a higher peak CK, these 55 patients had a higher incidence of early postinfarction angina (31 vs 14%; p less than 0.01), a similar hospital mortality (4 vs 7%) but a higher 3-year posthospital mortality (23 vs 12%; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical Enzyme Tests↗
PubMed1989

Prediction of mortality after myocardial infarction by simple clinical variables recorded during hospitalization.

Simple clinical variables obtainable in any coronary care unit and in any patient were recorded in 769 consecutive patients who were admitted with acute myocardial infarction (AMI) and who were discharged from the hospital and followed for up to 3 years. To identify the patients at highest and lowest risk of posthospital mortality, a prognostic index was established from a stepwise logistic discriminant analysis of variables obtained in a consecutive series of 418 patients discharged alive from one of two coronary care units admitting new patients on alternate days. This prognostic index was validated by applying it to a comparison group of 351 consecutive control patients discharged from the other coronary care unit. In the training group, 59 of the 418 patients (14%) died during the first year after hospital discharge and 34 (8%) died during the second or third year. The stepwise logistic discriminant analysis made it possible to distinguish between 1-year survivors and nonsurvivors, but not between the patients who died during the second and third years and the 3-year survivors. Four variables were selected for obtaining a 1-year prognostic index: the maximum grade of left ventricular function during hospitalization (0 to 4), history of previous AMI (1 or 0), predischarge cardiothoracic ratio (0 to 0.99), and complete bundle branch block (1 or 0). Prognostic index = 7.0196-0.6515 function - 1.6623 previous AMI - 0.0729 cardiothoracic ratio - 1.0813 bundle branch block. This index was validated in the comparison group.(ABSTRACT TRUNCATED AT 250 WORDS)

Bundle-Branch Block↗
PubMed1989

Relative prognostic value of clinical, biochemical, echocardiographic and haemodynamic variables in predicting in-hospital and one-year cardiac mortality after acute myocardial infarction.

This study examined the relative value of clinical, biochemical, echocardiographic and haemodynamic variables, obtained early after acute myocardial infarction in predicting in-hospital and one-year cardiac mortality in 66 consecutive patients. Clinical examination and cross-section echocardiography were obtained in all 66 patients. An echocardiographic score index was calculated by grading wall motion from 0 to 5 in each of 16 left ventricular segments. Right-sided cardiac catheterization was performed soon after admission in 51 patients. Cardiac enzymes were measured every fourth hour in all patients and peak levels were identified in 55. During the follow-up of one year, 14 patients died of cardiac causes, seven of them during hospital stay; three patients died of a non-cardiac cause and were excluded from analysis. The echocardiographic score index was the best predictor of cardiac death and survival (chi 2 = 35), followed by Killip class on admission (chi 2 = 22), stroke volume index (chi 2 = 17) and a biochemical risk index (chi 2 = 11). Stepwise logistic discriminant analysis performed in the patients in whom all variables were obtained resulted in three independent prognostic variables: the echocardiographic score index, systemic vascular resistance at the time of catheterization and the development of infarct expansion. High- and low-risk patients are well identified by echocardiography in the acute phase of myocardial infarction.

Acute Disease↗
PubMed1989

Haemodynamic alterations during ischaemia induced by dobutamine stress testing.

To identify the haemodynamic response to ischaemia induced by dobutamine stress testing, 15 patients with a first acute myocardial infarction underwent right-sided heart catheterization during dobutamine stress cross-sectional echocardiography. Haemodynamic variables and echocardiography were recorded at rest and during dobutamine infusion at each dose from 5 to a maximum of 40 micrograms kg-1 min-1. Ischaemia was diagnosed by cross-sectional echocardiography if asynergy appeared in at least two ventricular segments other than the area of acute myocardial infarction. Ischaemia was absent in six patients (group I) and identified in nine (group II). Response curves for each haemodynamic variable in the two groups were compared by applying Zerbe's method. The response curves were similar in the two groups for heart rate, arterial, right atrial, pulmonary arterial and pulmonary artery wedge pressures. The response curves were significantly different in groups I and II for thermodilution cardiac output, stroke volume and systemic vascular resistance (P less than 0.05). An increase in stroke volume was observed at low dosage of dobutamine in both groups. From low to maximum dose, stroke volume remained unchanged in group I and was significantly decreased in group II. Ischaemia induced by dobutamine stress testing leads to a decrease in stroke volume with no change in pulmonary artery wedge pressure.

Adult↗
PubMed1989

Student population changes and progress in Belgian medical schools.

The present study was designed to analyse the evolution of student populations--undergraduates and graduates--in the 11 Belgian medical schools from 1969 to 1982. During this period, an overall 44% drop in the number of entrants was observed, while the number of medical graduates continued to rise until 1977, when it stabilized. French- and Flemish-speaking universities followed a similar trend. During the period under study, the proportion of women students virtually doubled from 25 to 44%. The total success rate averaged 39% for Belgian students and 24% for foreigners. By comparing success curves over the years, the various medical faculties were rated with a 'selectivity' score, indicating those significantly different from the national average. A separate classification was made for preclinical (3 years of 'Candidature') and clinical (4 years of 'Doctorat') phases since, among the 11 Belgian medical schools, four teach only preclinical subjects. Marked differences in failure rates were observed between candidature and doctoral education even within universities.

Achievement↗
PubMed1989

Effects of pulsatile delivery of insulin and glucagon in humans.

The purpose of the present study was to investigate the respective effects of continuous intravenous delivery of both insulin and glucagon compared with those of pulsatile insulin (and continuous glucagon), pulsatile glucagon (and continuous insulin) and both hormones administered in a pulsatile manner (but out of phase) on various parameters of glucose turnover. The study was performed on six healthy male volunteers submitted to a 325-min glucose-controlled glucose intravenous infusion using the Biostator. The endogenous secretion of pancreatic hormones was inhibited by somatostatin (2 micrograms/min). Four combinations of continuous and pulsatile infusions of insulin and glucagon were performed on different days and in random order. The amounts of hormone infused were identical in all instances and were 0.2 mU.kg-1.min-1 (continuous insulin), 67 ng/min (continuous glucagon), 1.3 mU.kg-1.min-1 and 435 ng/min with a switching on-off length of 2-11 min (for intermittent insulin and glucagon delivery, respectively). In the case of pulsatile administration of both hormones, the pulses of insulin and glucagon were given out of phase with a 6-min interval. Blood glucose levels and glucose infusion rate were monitored continuously by the Biostator, and classic methodology using a D-[3-3H]glucose infusion allowed to study glucose turnover. When compared with pulsatile insulin and continuous glucagon, pulsatile glucagon and continuous insulin were characterized by a significantly higher endogenous (hepatic) glucose production. When both insulin and glucagon were delivered in a pulsatile manner, the effect of pulsatile glucagon was predominant, maintaining a high endogenous glucose production. Under no circumstance was an effect on glucose utilization or clearance detected. This study demonstrates that pulsatile delivery of insulin or glucagon in humans has greater effects in modulating endogenous glucose production than continuous infusion. Furthermore, when both insulin and glucagon are delivered intermittently and out of phase, the stimulatory effect of glucagon on endogenous glucose production prevails over the inhibitory effect of insulin.

Adult↗
PubMed1989

Relationship between whole plasma calcitonin levels, calcitonin secretory capacity, and plasma levels of estrone in healthy women and postmenopausal osteoporotics.

The exact role of calcitonin (CT) in the pathogenesis of postmenopausal osteoporosis remains unknown. Whole plasma calcitonin (iCT) basal levels, metabolic clearance rate (MCR), and production rate (PR) of CT were measured in 9 premenopausal and 16 postmenopausal women, including 11 osteoporotics (OP). Basal iCT levels were statistically lower in postmenopausal women than in the premenopausal group (P less than 0.01) and strongly correlated (r = 0.72; P less than 0.001) with estrone circulating levels (E1). MCR were similar in all groups. PR were similar in eugonadal women between 22 (mean +/- SD = 30.9 +/- 9.9 micrograms/d) and 37 yr (mean +/- SD = 25.5 +/- 11.1 micrograms/d) premenopausal women. In healthy postmenopausal women PR were reduced, but not significantly (mean +/- SD = 19.5 +/- 6.95 micrograms/d), whereas osteoporotic patients presented a highly significant reduction of CT PR (mean +/- SD = 9.8 +/- 4 micrograms/d) (P less than 0.01). Because there is a strong relationship between E1 and PR (r = 0.64; P less than 0.001), CT secretory capacity appears to be modulated by estrogen circulating levels. This modulation leads to a menopause-related decrease in iCT. In osteoporotics, an independent impairment of CT production drastically lowers PR and basal iCT levels. CT might be one of the determining factors in the pathogenesis of postmenopausal osteoporosis.

Adult↗
PubMed1989

Treatment of an enteric fistula with somatostatin in a premature.

The authors present the case of an extremely premature baby affected by severe Necrotizing Enterocolitis (NEC) needing intestinal resection and ileostomy. An enteric fistula developed 3 days after ostomy closure. The baby was started on Total Parenteral Nutrition (TPN), and 7 days later the fistula output remained constant. Somatostatin (SM) was then given intravenously (3.0 micrograms/Kg/hr) and the fistula closed on the 3rd day of treatment. Since SM was introduced in 1986 as an adjunct treatment to TPN in enteric fistulas, the authors believe that theirs is the first report of a successful SM treatment in a premature.

Enterocolitis, Pseudomembranous↗
PubMed1989

Improved outcome prediction based on CSF extrapolated creatine kinase BB isoenzyme activity and other risk factors in severe head injury.

The present study of 43 patients with severe head injury shows that outcome prediction can be markedly improved by combining an appropriate marker of the degree of initial brain damage and other risk factors. The patients were classified into three groups according to their actual outcome after 6 months: death (22 patients); persistent vegetative state or severe disability (eight patients); and moderate disability or good recovery (13 patients). By applying stepwise logistic discriminant analysis to the patients' data, five significant risk factors were selected: degree of neurological damage assessed by cerebrospinal fluid (CSF) extrapolated creatine kinase BB isoenzyme activity, Glasgow-Liège Coma Scale score, age, incidence of thoracic injury, and intracranial pressure (ICP). Extrapolated creatine kinase BB activity had the highest prognostic ability (67%). Uncontrollable elevated ICP proved to be systematically associated with death, whereas its absence was not necessarily indicative of a favorable outcome. The combination of the five variables yielded a total prognostic efficiency of 91%. The percentages of correctly predicted patients for the three outcome groups were, respectively, 100%, 50%, and 100%. Thus, half of the persistently vegetative and severely disabled patients were identified by the selected factors.

Adolescent↗
PubMed1989

[Usefulness and indications for Port-a-Cath in children with acute leukemia].

Duration of treatment for acute leukemia is as long as 2 years. During this time, venous punctures are repeated every few days. The Port-a-Cath system allows a long-lasting but intermittent venous access. Since March 1987, 11 Port-a-Cath systems have been implanted in 11 children (age 3 to 14) with the diagnosis of high risk acute leukemia (9 ALL and 2 AML). The facial vein has been used in five instances, the external jugular vein in five, and the jugular vein in one case. Ten systems have had a good function. Seven are still in use, and the duration ranges from 450 to 47 days. Two children died because of their disease, their catheters still functioning. Two systems have been withdrawn, one for incorrected location and the other for cutaneous necrosis of the puncture site. Two more children developed reversible thrombosis. The Port-a-Cath system is useful in children affected by high risk acute leukemia, ameliorating their life quality and avoiding the need for repeated vein punctures.

Acute Disease↗