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P Devos

Publications and source records attributed to P Devos.

At least 37 records · Page 2Linked to original sources
PubMed1999

Influence of mental stress and circadian cycle on postprandial lipemia.

BACKGROUND: Mental stress produces alterations in serum lipids and lipoproteins. OBJECTIVE: The objective was to assess the effect of mental stress during the day and night on postprandial lipoproteins. DESIGN: Fourteen healthy subjects aged 26.6 +/- 5.0 y were given randomly the same meal either at night (0100) or during the day (1300), with or without (control session) a mental stress challenge. The meal contained 40% of estimated daily energy needs. The mental task was performed on a computer and consisted of a task of choice reaction. Blood samples were drawn at baseline and hourly for 7 h after the meal. RESULTS: Urinary epinephrine concentrations were higher (P < 0.012) during the mental task than during the control sessions. Repeated-measures analysis of variance showed that mean postprandial triacylglycerol concentrations were significantly higher (P < 0.02) and total cholesterol (P < 0.0001) and HDL-cholesterol concentrations were significantly lower (P < 0.0001) at night than during the day. The mean postprandial VLDL-triacylglycerol concentration was significantly higher (P < 0.04) during the mental task than during the control sessions. Similarly, the VLDL-cholesterol response, calculated as the area under the postprandial curve, was significantly greater (P < 0.02) during the mental task than during the control sessions. There was no interaction between mental stress and nyctohemeral cycle on postprandial lipoprotein responses, suggesting that both indexes act independently on postprandial lipid metabolism. CONCLUSIONS: Mental stress is associated with increased concentrations of postprandial triacylglycerol-rich lipoprotein fractions. Therefore, postprandial hyperlipidemia is one possible mechanism contributing to the higher risk of ischemic heart disease in stressed people.

Adult↗
PubMed1999

Simplified prediction rule for prognosis of patients with severe community-acquired pneumonia in ICUs.

STUDY OBJECTIVES: To develop a simplified prognostic prediction rule for patients admitted to ICUs for severe community-acquired pneumonia (CAP). SETTING: Six ICUs in the north of France. PATIENTS: Five hundred five patients admitted to ICUs over a 9-year period (from 1987 to 1995) for severe CAP. INTERVENTIONS: Retrospective prognosis analysis and multivariate analysis using a credit scoring technique. MEASUREMENTS: The primary outcome measure was ICU mortality. RESULTS: Among the 505 patients, 472 were eligible for the prognosis study. The ICU mortality rate was 22.9%. Multivariate analysis identified, on the basis of the patient's medical history and initial examination on ICU admission, six independent predictors of mortality: age > or = 40 years, anticipated death within 5 years, nonaspiration pneumonia, chest radiograph involvement > 1 lobe, acute respiratory failure requiring mechanical ventilation, and septic shock. An initial risk score based on these factors classified patients into three risk classes of increasing mortality: 4% in class I, 25% in class II, and 60% in class III. Multivariate analysis of events occurring during ICU stay identified three independent predictors of mortality: hospital-acquired lower respiratory tract superinfections, nonspecific CAP-related complications, and sepsis-related complications. An adjustment risk score based on these factors was essential to accurately predict the final outcome of patients in the initial risk class II. CONCLUSIONS: As an aid to clinicians in stratifying the prognosis of patients with severe CAP, the simplified prediction rule used in this study could be useful for therapeutic decisions and appropriate care.

Community-Acquired Infections↗
PubMed1999

[Clinical results of angioplasty of the renal arteries in renovascular arterial hypertension. A retrospective study in 113 patients].

The aim of the study was to evaluate the clinical results of percutaneous transluminal renal angioplasty in a population of 113 consecutive hypertensive patients who underwent endoluminal revascularization for angiographically significant renal artery stenosis. Retrospective analysis of the case records of 104 patients showed that systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreased significantly 6 months after angioplasty (-20.9 mmHg and -8.4 mmHg respectively; p = 0.0001). This decrease was maintained until 19.8 months after the procedure. In cases with suboptimal revascularization (persistence of a residual stenosis more than 30%), only the SBP decreased significantly at 6 months (from 177 mmHg to 156.1 mmHg; p = 0.0061); when DBP decreased from 91.4 mmHg to 86.1 mmHg (NS) at 6 months, and fell to 80.9 mmHg (p = 0.026) at 19.8 months (after the performance of a second transluminal angioplasty for 41% patients of this group due to restenosis). Twenty-nine patients presented a restenosis of the renal artery 6 months after the initial procedure. In this group, only SBP decreased significantly at 6.1 months and at 18.7 months (from 171.9 mmHg to 156.1 mmHg and 146.5 mmHg respectively; p = 0.0064 and p = 0.0001). DBP decreased significantly only at 18.7 months (-12.6 mmHg; p = 0.0001), after a second renal angioplasty in 23 patients (79%). In the 60 patients without restenosis at 6 months, SBP and DBP decreased significantly at 6.1 and 18.7 months. No significant variation of creatinine levels was observed. These results confirm the utility of percutaneous transluminal renal angioplasty for the treatment of renovascular hypertension.

Angioplasty, Balloon↗
PubMed1999

A prototype of an information system for assessing the health status of prison inmates.

A research-action program was established in 1996 between the Loos-Lez-Lille prison psychiatric unit and the Department of Medical Informatics of the University Hospital of Lille (France):--(1) to investigate the health status and the general characteristics of the prison population--(2) to develop an Information System for improving the prison health care and to facilitate social rehabilitation of convicts. Starting off 1988, all new prisoners are interviewed on their arrival using a standard questionnaire. The transfer of all the information recorded in this questionnaire into a computer base was initiated in 1996, when the research action program began. A statistical analysis was performed on 15,200 records (1989-1995) to identify the most informative parameters: 50% of inmates were less than 24 years old; 57% were unemployed; 60% had no professional qualification. 31% of inmates had a psychiatric history and 16% had made a previous suicide attempt. The rate of drug abuse has increased from 24% in 89 to 53% in 95. To analyze the time trends of these parameters, a prototype of Information System was then developed. The system uses the database to product standard reports in real time.

Adolescent↗
PubMed1999

QUALIDIAB: implementation of the Diabcare project in the French-speaking environment: regional, national and international issues. Qualidiab Group.

Diabcare is an international Project devoted to the evaluation of the Quality of Care [1] in the population of diabetic patients. As Diabetes is one of the most frequent chronic illnesses, the management of its treatment has a strong impact on the public health policy both regional and national [2]. Funded by the European Commission, initiated by WHO and the International Diabetes Federation (IDF), this Project is now recognised as a Pilot Project throughout the world as an example of a large international collaboration for the surveillance of quality of care in a typical chronic disease.

Computer Security↗
PubMed1998

Potentiating effect of metformin on insulin-induced glucose uptake and glycogen metabolism with Xenopus oocytes.

Xenopus laevis oocytes were chosen as the in vitro model for this study with the aim of reconsidering metformin action on the main insulin-responsive glucose pathway. Metformin alone, when present at a therapeutic dose (20 micromol/l) in the incubation medium, did not alter the basal rate of glucose uptake or of glycogen synthesis as measured by [U-14C] D-glucose incorporation. The drug had no effect on the main rate-limiting enzyme implicated in this pathway, i.e. glycogen synthase. In contrast, when combined with 2 micromol/l insulin, metformin led to a specific rise of both free and stored glucose, by 42.4 and 102.3% respectively. Moreover, a short-term preincubation of mature oocytes with metformin, but in the absence of glucose, enhanced significantly the amount of synthase a when stimulated by 50 nmol/l insulin (basal 17.4 +/- 5.7%, metformin 21.3 +/- 4.1%, insulin 31.2 +/- 4.6%, metformin together with insulin 62.7 +/- 4.2%, p < 0.005, n = 5). Interestingly, the microinjection of this biguanide, at a final concentration of 20 nmol/l, allowed a similar biochemical response. These data clearly suggest that metformin could act primarily at postreceptor steps which are thought to be key sites in controlling the cellular glucose homeostasis.

3-O-Methylglucose↗
PubMed1998

Relationships between severe neonatal thrombocytopenia and maternal characteristics in pregnancies associated with autoimmune thrombocytopenia.

In pregnant women with antecedents of autoimmune thrombocytopenia (AITP), no predictive factor for severe fetal thrombocytopenia has been identified. We evaluated the relationships between the course of the maternal disease before and during pregnancy and the risk of severe fetal thrombocytopenia, in 64 pregnant women with known chronic AITP antecedents, over a 12-year period. 28 pregnant women had undergone splenectomy before pregnancy and 17 experienced severe thrombocytopenia (< 50 x 10(9)/l) during pregnancy (monthly determination). Eight infants presented with severe thrombocytopenia at birth (12.5%), and four in the following days (6.25%). No severe haemorrhage was observed. Severe thrombocytopenia at birth was present in 57% (CI 95% 18-90%) of the infants born to mothers with severe pregnancy-associated thrombocytopenia and splenectomy antecedents, and in 0% (CI 95% 0-15%) of the infants born to mothers who presented none of these antecedents (P=0.001). In thrombocytopenic mothers the infant platelet counts at birth were positively correlated to the nadir maternal platelet count during the index pregnancy (r=0.42, P=0.0075). These results suggest that severe autoimmune disease is a risk factor for severe fetal thrombocytopenia, and that pregnant women with no antecedent of splenectomy nor severe thrombocytopenia during pregnancy have a very low risk of severe fetal thrombocytopenia.

Chronic Disease↗
PubMed1998

[Modifications of heart rate and blood pressure during pregnancy].

The pathophysiology of pre-eclampsia, disease of the endothelium, placental ischaemia, and its consequences on blood pressure and heart rate variations are described. The methods of evaluation of heart rate and blood pressure during pregnancy, outpatient visit clinical measurement, self-measurement, ambulatory measurement, "Finapres", electrocardiogram and Holter ECG are reviewed; the practical implications of the nocturnal fall of vagal tone with tachycardia, demonstrated during pre-eclampsia, are discussed.

Blood Pressure↗
PubMed1994

Insulin but not progesterone promotes the biosynthesis of glycogen in Xenopus laevis oocytes: implications on the control of glycogen synthase by phosphorylation, dephosphorylation.

Insulin, the well-known hypoglycemic hormone, mimics progesterone in promoting the resumption of meiosis within the oocyte of Xenopus laevis. Both hormones exert their action through the inhibition of protein kinases and the activation of protein phosphatases. Because glycogen synthase is an enzyme regulated by a kinases/phosphatases cascade, we investigated the effect of insulin and progesterone on the regulation of glycogen synthesis and glycogen synthase throughout the oogenesis of Xenopus laevis oocytes. In this framework the maximal activity of synthase "a" is concomitant with the vitellogenic period characterized by a drastic increase in the amount of glycogen. Oocyte glycogen synthase is inhibited by cAMP-dependent phosphorylation and stimulated by 20 mM Mg2+. The magnesium effect is inhibited by mu molar concentrations of okadaic acid and suggests that oocyte glycogen synthase is activated by dephosphorylation achieved by protein phosphatase-1. The okadaic acid effect is itself thwarted by the specific inhibitor of protein kinase A, confirming the role of this kinase in the regulation of glycogen synthase. Finally, working on intact ripe oocytes, we showed that insulin but not progesterone increases glycogen synthesis and glycogen synthase "a" activity and lowers the rates of phosphorylation, especially in the glycogen-bound proteins.

Animals↗
PubMed1994

Evidence for time-dependent activation of monocytes in the systemic circulation in unstable angina but not in acute myocardial infarction or in stable angina.

BACKGROUND: Platelet activation plays a pivotal role in the pathogenesis of acute coronary disease. Monocytes are involved in the progression of atherosclerosis and are potent activators of blood coagulation through their ability to synthesize tissue factor (TF). The aim of this study was to compare markers of monocyte and coagulation activation in the systemic blood of patients with unstable angina, acute myocardial infarction, or stable angina. METHODS AND RESULTS: We studied 26 patients with unstable angina (10 +/- 5 hours after the onset of the last episode of pain), 18 patients with acute myocardial infarction (5 +/- 4 hours after the onset of pain), and 34 patients with stable angina. We measured levels of TF expression in peripheral blood mononuclear cells (isolated by gradient centrifugation and incubated for 16 hours, with or without endotoxin stimulation), levels of plasma prothrombin fragment 1 + 2 (F1 + 2), and levels of fibrinogen in peripheral blood. In patients with unstable angina, both stimulated and unstimulated cells exhibited higher levels of TF expression than in patients with stable angina (P = .0001). In patients with acute myocardial infarction, monocyte TF activity did not differ from that in patients with stable angina. Mean levels of F1 + 2 and of fibrinogen did not differ significantly between groups. Only in the unstable angina group, a modest correlation was found between fibrinogen (r = .72, P = .005) and F1 + 2 levels (r = .54, P = .001) levels and the degree of monocyte TF expression. In patients with unstable angina, monocyte TF expression (both stimulated and unstimulated, assessed by biological activity and by antigen techniques) and fibrinogen levels were correlated with the time elapsed from the beginning of the most recent episode of pain (.61 < r < .72, .02 < P < .0001). By contrast, there was no correlation between these variables and the time from onset of pain in patients with acute myocardial infarction. CONCLUSIONS: A time-dependent activation of systemic monocytes and a time-dependent increase in fibrinogen levels occurs in unstable angina but not in myocardial infarction. These findings provide further evidence that a specific inflammatory process occurs in unstable angina. Further studies are required to determine whether monocyte activation is a cause or a consequence of plaque instability in patients with unstable angina and to clarify the interrelations between platelet and monocyte activation in these circumstances.

Adult↗
PubMed1993

Developmental extinction of liver lipoprotein lipase mRNA expression might be regulated by an NF-1-like site.

The molecular mechanism underlying the extinction of lipoprotein lipase (LPL) expression in rat liver during development was investigated. A mouse (BWTG3) and a rat (7777) hepatoma, both of which exhibit characteristics of fetal hepatocytes, were found to contain LPL mRNA, whereas the more differentiated human (Hep G2 and Hep 3B) or rat (Fa32) hepatoma cell lines did not. Somatic cell hybrids between LPL-producing hepatoma cells and non-LPL-producing cells, such as adult rat hepatocytes or fibroblasts, exhibited extinction of LPL gene expression. Assay of expression of nested deletions in the 5' regulatory sequences of the LPL gene in the Hep G2 cell line and in BWTG3 cells localized sequences involved in the suppression of LPL production to a region between -591 and -288 relative to the transcription initiation site. A site with sequence homology to a glucocorticoid responsive element (GRE) was shown not to play an important role in the extinction process. A novel transcription factor, termed RF-1-LPL, was shown to bind to an NF-1-like site in this region. In contrast to neonatal animals, in adult animals an additional protein complex (RF-2-LPL), was formed on the NF-1-like site, suggesting that this sequence might recruit a trans-acting factor involved in the extinction of LPL gene expression in adult rat liver.

Animals↗
PubMed1993

Cobalamin absorption and serum homocysteine and methylmalonic acid in elderly subjects with low serum cobalamin.

We prospectively studied 41 consecutive elderly patients with serum cobalamin (vitamin B12) levels lower than 125 pmol/l. The protein-bound cobalamin absorption test (PBAT) was performed in 34 of them and in 27 selected elderly control patients. The lower decision limit was 0.18% and an abnormal test was detected in only 9 (26%) of the 34 patients with low serum cobalamin level. When the PBAT was compared to the Schilling (Dicopac method) test, a concordant result was found in 80%. Serum methylmalonic acid and/or total homocysteine concentrations were elevated in 75% (26/35) of the patients with low serum cobalamin levels but also in 30% (5/17) of the control patients. Of the 12 and 9 cobalamin-deficient patients with elevated serum levels of methylmalonic acid and homocysteine, normalization after cobalamin therapy was obtained in 11 and 5 respectively. In conclusion, determination of serum metabolites and their response to cobalamin therapy are a sensitive index of significant cobalamin deficiency and a useful means of distinguishing between cobalamin and folate deficiency. The PBAT offers little advantage over the Schilling test in diagnosing cobalamin malabsorption in elderly patients.

Aged↗
PubMed1992

Alterations of the mineralization profile and osteocalcin concentrations in osteoarthritic cortical iliac crest bone.

The relation between bone mineralization and osteocalcin content was investigated in iliac crest cortical bone obtained at necropsy in young females and in two groups of elderly women with and without osteoarthritis of the hands evaluated by X-ray. Using density fractionation technique, the bone was separated into fractions of increasing density from 1.72 to 2.30 g/ml. The mineralization profile revealed a significant shift to higher densities in the osteoarthritis cases compared with young adults (P less than 0.005) and age-sex-matched controls (P less than 0.001). The ash, calcium, and phosphorus content of the bone increased with increasing density of the fractions whereas collagen content, measured as hydroxyproline, decreased. The osteocalcin concentration of each fraction was determined in the supernatants obtained after EDTA-extraction in the presence of protease inhibitors. In the young control and osteoarthritis group, the osteocalcin content in the lowest density fractions was higher compared with the older non-osteoarthritic group. Osteocalcin content of the high density fractions, representing highly mineralized osteons, was the same in the three groups studied. These findings support the hypothesis that quality differences in bone may explain the inverse relationship between osteoarthritis and osteoporosis.

Adult↗
PubMed1991

Short-term course of 1,25(OH)2D3 stimulates osteoblasts but not osteoclasts in osteoporosis and osteoarthritis.

We investigated the effect of short-term, 1,25-dihydroxyvitamin D3 therapy (4 micrograms/day for 4 days) on calcium metabolism in 27 postmenopausal women (11 cases with osteoporosis and 16 cases with osteoarthritis). Bone mass at the axial and appendicular skeleton was higher in osteoarthritis than in osteoporosis. Initial values of calcium metabolism were similar. Osteoporotic and osteoarthritic patients responded with a similar significant increase in serum osteocalcin (+61% and +54%, respectively), fasting urinary calcium excretion (+178% and +124%, respectively) and 24 hour calcium excretion (+148% and +142%, respectively). Parathyroid hormone (PTH) levels decreased significantly in both groups (-30% and -18%, respectively). Osteoclastic bone resorption, evaluated by urinary hydroxyproline excretion, was not stimulated in either group. We conclude that in osteoporosis and also in osteoarthritis (1) 1,25-dihydroxy-vitamin D3 (1,25(OH)2D3) stimulation of osteoblast function is similar in production of osteocalcin; (2) the vitamin D target tissues react adequately to 1,25(OH)2D3 stimulation; (3) short-term high dose of 1,25(OH)2D3 does not stimulate bone resorption; and (4) the differences in bone mass between osteoarthritis and osteoporosis are not related to an alteration of the responsiveness to stimulation by 1,25 (OH)2D3.

Aged↗
PubMed1991

Seasonal variation in bone metabolism in young healthy subjects.

Serum vitamin D metabolites and urinary calcium excretion; parameters of bone formation (serum alkaline phosphatase, serum osteocalcin); parameters of bone resorption (24 hour hydroxyprolinuria, 2 hour fasting urinary hydroxyproline/creatinine ratio); and parameters of cortical and trabecular bone density, parathyroid hormone (iPTH, COOH terminal assay), and serum minerals (calcium, phosphorus) were followed serially in 55 young adults (21 women and 34 men) from December 1985 until January 1987 at four different times during the year. The effect of a low-dose cyclooxygenase inhibitor (piroxicam 5 mg daily) on the same parameters of bone density and bone turnover when given from December until May, was also evaluated in this study. At the end of the treatment period parameters of bone turnover and bone density were comparable between placebo and piroxicam-treated groups. Therefore, the results of all subjects were pooled in order to investigate seasonal variation. In both sexes, seasonal variation was found not only for 250HD3 but also for 1,25(OH)2D3, serum calcium and phosphorus, urinary calcium excretion, and for bone density at the lumbar spine. Parameters of bone formation (serum osteocalcin and alkaline phosphatase), bone resorption (24 hour urinary hydroxyprolinuria and fasting urinary hydroxyproline/creatinine ratio) and PTH were influenced by this seasonal variation. We conclude that in young adults, a significant seasonal variation occurs, with low winter and high summer values, for serum 25 and 1,25(OH)2D3 for urinary calcium apparently without important influence on parameters of bone turnover or parathyroid activity and for lumbar spine density. Treatment with a low-dose cyclooxygenase inhibitor was without influence on the observed changes.

Adult↗
PubMed1991

Electromagnetic extracorporeal shock wave lithotripsy in children.

Extracorporeal shock wave lithotripsy (ESWL) was performed for the treatment of urinary tract calculi in 28 children. All treatments were done with the standard Siemens Lithostar device in situ: no special adaptations for adequate positioning of children are required to target the stone precisely. A total of 42 calculi in 30 renal units was treated, requiring 50 ESWL sessions. The mean energy used was 16.4 kv. and the number of shock waves averaged 3,188. Mean fluoroscopy time per session was 1.5 minutes. In 26 of 50 sessions (52%) general anesthesia was needed for the child to remain perfectly still. A complete stone-free rate was achieved in 38 of 42 calculi (90.5%): after 1 session in 30 (71.4%), after 2 sessions in 6 (13.7%) and after 3 sessions in 2 (4.8%). Five staghorn calculi were treated with ESWL monotherapy. A complete stone-free result was obtained after 3 treatments in 2 patients, while 2 had residual fragments in the lower pole (5 mm. after 6 sessions and 11 months of followup in 1, and 7 mm. after 3 sessions and 3 months of followup in 1). A cystine staghorn stone necessitated open nephrolithotomy after 3 sessions without any fragmentation. One impacted sacroiliac ureteral stone required endoscopic laser lithotripsy. Except for these 2 failures no adjuvant procedures were needed. There were no intraoperative or postoperative complications and minor skin bruising at the coupling site after 3 treatments did not require any therapy. We conclude that electromagnetic ESWL with the standard Lithostar unit is a safe and effective method to treat calculi throughout the urinary tract in children.

Adolescent↗