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P Simon

Publications and source records attributed to P Simon.

At least 181 records · Page 10Linked to original sources
PubMed1996

[Epidemiologic data, clinical and prognostic features of autosomal dominant polycystic kidney disease in a French region].

Epidemiological study on autosomal dominant polycystic kidney disease (ADPKD) was undertaken in a French region from 1988 to 1993. This survey was led in a population of 410,000 inhabitants and 84 kindreds with ADPKD and 296 affected members were studied. Prevalence of ADPKD in the studied region was calculated to 1/1111 inh. Renal prognosis was evaluated according to the Kaplan-Meier method in 296 affected subjects of whom 212 were members of propositus kindreds. In our region 17% of patients had ESRD by the age of 50 years, 47% by the age of 60 years and 70% by the age of 70. No significance difference was found between males and females. The influence of the sex of the parent from whom ADPKD was received on the renal prognosis of the disease in affected descendants was evaluated. Anticipation of ESRD for at least one offspring inheriting ADPKD from parent was found in 15 (38%) out of 39 families, without genetic imprinting linked to gender. Mean survival to ESRD for fathers transmitting ADPKD to offspring (52 +/- 10 years) was significantly earlier compared to that for mothers transmitting ADPKD (61 +/- 10 years, p < 0.001), therefore that for siblings inheriting the disease from their fathers (sons: 49 +/- 7 years, daughters: 51 +/- 9 years) and for those inheriting ADPKD from their mothers (sons: 57 +/- 10 yrs, p < 0.01, daughters: 55 +/- 6 yrs, p < 0.02). Prevalence of de novo mutations was evaluated to 1/135,000 inh. Adult polycystic disease of the liver (APLD) was studied in 82 kindreds with 158 ADPKD affected members by ultrasonography and/or CT. In patients with APLD, 49/84 (58.3%) were females compared to 46/74 (62.2%) in those without APLD. Familial APLD (at least 2 affected members and all with APLD) was demonstrated in 22/27 APLD kindreds (81.5%). Familial ADPKD without APLD (at least 2 affected members and all without APLD) was demonstrated in 12/12 kindreds (100%). Renal prognosis of ADPKD in 84 APLD pts was compared to that in 71 non-APLD pts, in whom mean age was not different at the time of the study. In APLD pts 28/84 (33.3%) had reached ESRD compared to 23/71 (32.3%) non-APLD pts (ns). The occurrence of stroke in ADPKD patients was documented in 24/231 pts (10.4%) from 11/82 kindreds (13.4%). Family history of cerebro-vascular event was found in 4/11 kindreds (36%).

Adult↗
PubMed1996

[An epidemiologic approach for the prevention of renal insufficiency].

Primary and secondary prevention of disease is among major goals of medicine. End stage renal disease (ESRD) is too expensive for society and its progression can be prevented or slowed down in many patients. In order to manage such an objective, clinical means as the search of urinary abnormalities and infection, as the measurement of plasma creatinin and microalbuminuria, the recording of blood pressure must help to create the nephrovigilance. Descriptive epidemiological data seem in favour of a progression of the incidence of ESRD due to development of vascular nephropathy, diabetes type II or toxic interstitial nephropathy. Analytic epidemiology studies suggest the implication of numerous environmental factors for progression of renal disease, whatever its type. Nephrologists, with preventive medicine, practitioners and other specialists, have to implicate themselves in the early diagnosis of renal diseases.

Albuminuria↗
PubMed1996

[A familial history of hypertension is associated with the development of hypertension and nephroangiosclerosis in patients with glomerulonephritis caused by mesangial IgA deposits].

The progress of IgA Nephropathy (IgAN) is correlated with glomerular and vascular sclerosis. Renal vascular lesions, i.e. nephrosclerosis, often precede the onset of hypertension (HBP) in young patients with IgAN. It is also recognized that a family history of HBP (FHBP) is strongly predictive of future onset of HBP in family members, when two or more first-degree relatives with HBP are identified. In order to examine the possible link between FHBP and nephrosclerosis, we compared 2 groups of 29 pts each (23 M and 6 F) with IgAN, matched for age and sex, according to the presence or absence of FHBP. FHBP was considered present if at least 2 or more 1st degree relatives under 60 years of age received antihypertensive Rx. Parents and siblings of patients were examined at home by two investigators. Patients with FHBP (+) and FHBP (-) were aged 36 +/- 12 and 35 +/- 12, respectively, at the time of renal biopsy and the follow-up was conducted for an average of 4.6 years. At the end of this survey, HBP and renal failure (Cr Cl < 80 ml/min) were reevaluated in all patients. At the time of renal biopsy, nephrosclerosis was significantly associated with FHBP: FHBP (+): 96.5% versus FHBP(-): 10.3%; p < 0.0001. At the end of the follow-up, FHBP was found to be associated with HBP (89.6% versus 10.3%; p < 0.001) and with renal failure (44.8% versus 3.4%; p < 0.001). These data suggest that nephrosclerosis has a strong genetic component in patients with IgAN, FHBP is an early clinical indicator of nephrosclerosis in these patients and that FHBP is a strong indicator of unfavorable prognosis in IgAN.

Adult↗
PubMed1996

[Risk factors for acute hypersensitivity reactions in hemodialysis].

The aim of this prospective study was to evaluate the prevalence of anaphylactoid reactions (AR) in patients dialysed with cellulose or synthetic membranes and the possible link with ACE inhibitors. Survey was conducted for six months (Jan, 1 to July, 1 1993). Thirty dialysis units treating 1573 patients (899 M and 674 F) were participating to the study. At the end of the period under study, only 1536 patients were included in the analysis. Prevalence of AR was calculated from 122 694 hemodialysis sessions. Thirty-three AR in 21 patients (1.3%) (8 M, 13 F), of which 8 severe AR in 5 patients (0.25%) were observed. Annual incidence of AR was 0.17 per 1000 sessions with cellulose membranes and 4.2 per 1000 sessions with synthetic membranes. Relative risk of the occurrence of AR was 10 to 20 times higher with synthetic membranes than cellulose membranes, and 3 to 4 times higher in patient treated with ACE inhibitors than in those no treated. Prevalence of AR with AN69 membrane (3.2%) was not significatively different from that with other synthetic membranes (1.6%). However, treatment with ACE inhibitors increased strongly the risk of AR in AN69 patients (7.2%) in comparison to patients treated with other synthetic membranes (1.6%) ( < 0.1). Prevalence of severe AR was 0.25% in total dialysed population, 0.5% in patient treated with synthetic membranes, 1.1% in AN69 patient and 4.9% in AN69 patients treated with ACE inhibitors. Relative risk of AR is at least 20 times higher in dialysed patients with ACE inhibitors (1.7%) than other dialysed patients without ACE inhibitors (0%). Seventy-two percent of AR occurred in 2/30 dialysis units, thus demonstrating the role of a "un effect". That suggest the role of a "third factor" in the occurrence of AR.

Adult↗
PubMed1995

Serum pyridinoline as a specific marker of collagen breakdown and bone metabolism in hemodialysis patients.

Type I collagen represents more than 90% of bone matrix. Quantitative analysis of collagen cross-link molecules such as pyridinoline (PYD) provides valuable information on bone resorption rate. We have studied 37 hemodialysis patients who underwent a systematic transiliac bone biopsy for histomorphometry study. Eighteen of them had tetracycline double labeling, allowing to determine dynamic, in addition to static bone parameters. Measurement of serum-free PYD was performed using a new competitive enzyme immunoassay. Serum PYD values were compared with those of three other serum markers of bone metabolism, namely intact PTH (iPTH), bone-specific alkaline phosphatase (bAP), and osteocalcin, for the correlations with bone histomorphometric parameters. Serum PYD levels (mean +/- SD) were significantly higher in dialysis patients than in normal individuals, 90.6 +/- 99.6 nM versus 1.9 +/- 0.4 nM, respectively. Patients with high turnover bone disease had significantly higher serum PYD levels than patients with normal or low bone turnover, 108.8 +/- 108.0 nM versus 34.1 +/- 12.8 nM, respectively. Serum PYD levels were positively correlated with bone resorption parameters including osteoclast surface (r = 0.59, p < 0.0001) and osteoclast number/mm2 (r = 0.61, p < 0.0001), and also with bone formation parameters, osteoblast surface (r = 0.43, p < 0.008), double-labeled surface (r = 0.81, p < 0.001), and BFR (r = 0.91, p < 0.0001). The BFR was better correlated with serum PYD levels than with either serum iPTH or osteocalcin concentrations. However, correlation with serum bAP was comparable.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Can amputation be avoided in local recurrence after limb salvage for high grade osteosarcoma? A case report and a review of the literature.

We report a case of local recurrence after a limb salvage procedure for high grade osteosarcoma. We carried out a second salvage operation because the lesion was small, there were no distant metastases, the patient had initially responded to chemotherapy and was able to receive more drugs. She is still alive, well and free of disease more than 6 years after the second operation, and 9 years after the diagnosis was made. Amputation is not always needed for every case of recurrence.

Amputation, Surgical↗
PubMed1995

Echocardiographic results after repair of incompetent bicuspid aortic valves.

INTRODUCTION: Valve-related complications and the necessity of anticoagulation after aortic valve replacement have led to new operative techniques for correction of aortic insufficiency (AI). Fourteen patients with bicuspid aortic valves and significant AI underwent valve repair. METHODS: Transthoracic echocardiography was performed preoperatively and 1 week postoperatively and in 10 patients who have come to follow-up so far. Operative procedures were triangular resection of one leaflet in all patients. Five patients had pericardial patch plasty in addition. RESULTS: Mean AI decreased significantly from grade 3.5 +/- 0.1 preoperatively to 0.5 +/- 0.1 postoperatively (p < 0.001). Postoperatively, 10 patients had no or trivial AI (0 to 0.5), and 2 patients had mild AI (1 to 1.5). Within the first week, 2 patients were reoperated on after echocardiography established significant AI. Ventricular dimensions decreased from preoperative to postoperative and were normal after 1 year. At follow-up, 7 patients show no change of AI; in 3 patients AI increased to moderate because of dilatation of the sinus of Valsalva or the sinotubular junction. CONCLUSIONS: Reconstruction of bicuspid aortic valves is feasible with good early results. Echocardiography shows that asymmetric sinuses may lead to early perioperative failures and postoperative dilatation of the proximal aorta to increasing AI. Operative techniques may have to consider the pathology of the proximal aorta.

Adolescent↗
PubMed1995

Experience with 1251 transcervical chorionic villus samplings performed in the first trimester by a single team of operators.

OBJECTIVE: We report our experience with 1251 chorionic villus samplings (CVS) performed by a single team of operators. STUDY DESIGN: From April 1984 through August 1993, 1251 CVS were performed in 1236 pregnancies. The transcervical route was used in the vast majority and the sampling was performed during the 9th through 13th weeks of gestation in 1193 cases (96%). Follow-up was ensured to tabulate the pregnancy-related complications and fetal loss rate until 28 weeks' gestation. Pregnancy outcome was documented for all but 36 women (3%). RESULTS: Most of the tests (72%-891/1236 pregnancies) were performed for advanced maternal age (> or = 35 years). The percentage of each indication remained relatively stable, around 90% for chromosomal indications and between 8 and 11% for DNA studies. Samples adequate for diagnosis were obtained in one or two sessions in 1179 pregnancies (95%). The rate of spontaneous abortion possibly related to CVS was 2.5% (28/1092). Mosaicism confined to the placenta was found in 23 cases (1.8%). The pregnancy outcome was known in 1098 pregnancies. There were 10 perinatal losses (0.9%) and nine congenital malformations (0.8%). No transverse limb defects were observed. The rate of premature deliveries (4.6%) and of small for gestational age were comparable to the general uninstrumented population. CONCLUSION: CVS is a safe and effective mode of antenatal diagnosis when performed by a single team of experienced operators.

Adult↗
PubMed1995

[Erythropoietin and arterial hypertension in patients with chronic renal insufficiency].

The induction or the aggravation of a hypertension is a side effect of recombinant human erythropoietin therapy in 30% of dialysed patients. Clinical manifestations can be severe. Pathogenesis of erythropoietin-induced hypertension is ill known. Peripheral vascular changes were found in most studies. Recently, it was demonstrated that erythropoietin increased endothelin-1 release by endothelial cells. Ambulatory blood pressure recording seems to be the best method for evaluating the modification of blood pressure profile during the interdialytic period. Erythropoietin-induced hypertension is easily controlled by drugs, but also by low dose of erythropoietin. Subcutaneous administration of erythropoietin is an approach to avoid the induction of hypertension. Furthermore economical advantages of subcutaneous administration are proven.

Anemia↗
PubMed1995

The dopamine D3 receptor and schizophrenia: pharmacological, anatomical and genetic approaches.

Antipsychotic drug therapy mainly rests on the use of antagonists of dopamine D2-like (D2, D3 and D4) receptors, for which all clinically active compounds have high affinity. The D3 receptor has a restricted expression in brain limbic areas, associated with cognitive functions and motivated behavior. D3 selective agonists and antagonists reveal an inhibitory role on motor behaviors for the D3 receptor, opposite to that of the D2 receptor. An opposing role for D2 and D3 receptors is also suggested by the contrasted effects of D2/D3 antagonists on neurotensin expression in discrete subdivisions of nucleus accumbens, where D2 and D3 receptors are selectively expressed. Tolerance to the motor but not to the therapeutic effects of neuroleptics is observed after repeated administration, which upregulates the D2, but not the D3 receptor in animals. In genetic association studies, an excess of homozygosity for both alleles of the BalI polymorphism at the D3 receptor gene was found in schizophrenic patients, suggesting that this gene may have subtle influence on the liability to develop schizophrenia. These results suggest the D3 receptor as an important target for antipsychotic drug action, and D3 receptor selective antagonists as promising therapeutic agents.

Animals↗
PubMed1995

Non-amphetaminic mechanism of stimulant locomotor effect of modafinil in mice.

Previously established dose-response curves indicated that modafinil 20-40 mg/kg i.p. elicited in mice an obvious stimulation of locomotor activity roughly similar to that induced by (+)amphetamine 2-4 mg/kg. The effects of various agents modifying dopamine transmission were compared on the locomotor response to both drugs. The preferential D2 dopamine receptor antagonist haloperidol 37.5-150 micrograms/kg i.p. suppressed the stimulant effect of (+)amphetamine in a dose dependent manner, but not that of modafinil. The D1 dopamine receptor antagonist SCH 23390 (7.5-30 micrograms/kg s.c.) reversed the (+)amphetamine but not the modafinil induced hyperactivity. The tyrosine hydroxylase inhibitor alpha-methyl-para-tyrosine (200 mg/kg) suppressed the hyperactivity induced by 4 mg/kg dexamphetamine but not that induced by 20 mg/kg modafinil. Associating L-DOPA 150 mg/kg and benserazide 37.5 mg/kg with (+)amphetamine 2 mg/kg resulted in stereotyped climbing behavior, that was not observed with modafinil 10-80 mg/kg. The profound akinesia induced by reserpine (4 mg/kg s.c.; 5 h before testing) was reversed by (+)amphetamine 2 mg/kg but not by modafinil 40 mg/kg. Finally, on synaptosomes prepared from mouse striata preloaded with [3H]dopamine, modafinil 10(-5) M did not increase the spontaneous [3H]dopamine release whereas (+)amphetamine, at the same concentration, doubled it. From all these differences between the two drugs, it is concluded that the mechanism underlying the modafinil induced stimulant locomotor effect differs completely from that of (+)amphetamine.

Animals↗
PubMed1995

Transoesophageal echocardiographic follow-up of patients with surgically treated aortic aneurysms.

In the present study, biplane transoesophageal echocardiography (TEE) was scheduled as part of an aneurysm surveillance programme during routine ambulatory follow-up of 37 patients following aortic aneurysm surgery. Time from surgery ranged from 3-72 months. Twenty-two patients had had aortic dissection and 15 non-dissecting aneurysms. Nineteen patients received an interposition graft of the ascending aorta, 12 valved conduit and six an interposition graft of the descending thoracic aorta. TEE showed enlargement of the sinus of Valsalva > 45 mm in seven patients. Dilatation > 45 mm of one or more aortic segments was found in four patients. An intimal flap was present in all patients, with primary aortic dissection if the initial dissection extended beyond the replaced segment. This was the case in 17 of 22 patients with aortic dissection. One to four intimal tears were identified in 15 of these patients. In all patients with intimal tears, flow was detected by colour flow Doppler in the false lumen. Thrombus formation was nil or minimal in the false lumen in 12 patients. TEE significantly influenced further management in 14 of 37 patients (38%). More frequent follow-up was scheduled in eight patients. Aortic surgery was performed electively for the second or third time in six patients based on TEE findings. We conclude that after surgical repair of aortic aneurysm, the incidence of pathological findings by TEE is high. These may have significant influence on further patient management and emphasize the need for careful follow-up.

Adult↗