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J Aigueperse

Publications and source records attributed to J Aigueperse.

At least 19 recordsLinked to original sources
PubMed1998

In vivo alterations of fluid and electrolyte fluxes in rat colon by gamma irradiation.

Colonic function in rats was investigated up to 14 days following exposure to whole-body gamma irradiation (8 Gy) using a combination of in vivo and in vitro approaches. Water and electrolyte fluxes were measured in vivo under anesthesia by insertion of an agarose cylinder into the descending colon. Short-circuit current responses (Isc; basal, agonist-stimulated) of distal colon were measured in vitro as were mannitol and sodium fluxes. Water and electrolyte absorption (Na, Cl) was markedly reduced at four days after irradiation but returned to normal at seven days. Potassium secretion was increased from one to seven days after exposure. There were no differences in basal Isc, Na, or mannitol fluxes at four days but responses to secretagogues (5-hydroxytryptamine, forskolin, carbachol) were attenuated. No morphological alterations were associated with these functional modifications.

Animals↗
PubMed1998

Exposure to ionizing radiation modifies neurally-evoked electrolyte transport and some inflammatory responses in rat colon in vitro.

PURPOSE: To characterize the responsiveness of the colon to neural stimulation following acute exposure of rats to gamma-radiation and to correlate observed changes to a number of parameters. MATERIALS AND METHODS: Rats were exposed to 5 or 10 Gy 137Cs gamma-radiation or not (sham-irradiated) and studied at 1, 3 and 7 days after irradiation. Stripped segments of colon were mounted in Ussing chambers for measurements of neurally-evoked electrolyte transport (electrical field stimulation). Colonic tissue was also taken for biochemical (tissue 5-hydroxytryptamine, histamine, leukotriene B4, nitric oxide synthase) and histological analyses (mast cells). RESULTS: In irradiated rats both proximal and distal colon were hyporesponsive to electrical field stimulation at 1 and 3 days, but had recovered by 7 days. In the distal colon, carbachol responses were attenuated 1 day after 10 Gy. Mast cells, tissue histamine and leukotriene B4 synthesis were significantly reduced at all time points but no changes were seen in 5-HT or inducible NOS activity. CONCLUSIONS: Rat colon becomes hyporesponsive to neural stimuli post-irradiation. The response initially (1 and 3 days) correlates with decreased mast cells and histamine, but not at 7 days.

Animals↗
PubMed1998

Effects of ionizing radiation (neutrons/gamma rays) on plasma lipids and lipoproteins in rats.

Male Wistar rats weighing 250 g were exposed to 4 Gy of neutrons/gamma radiation (3.33 Gy of neutrons and 0.66 Gy of gamma rays). After whole-body irradiation, plasma cholesterol and phospholipid levels increased up to 62 and 37%, respectively, at day 4 and then returned to control values 12 days after irradiation. Plasma triglyceride concentrations decreased concomitantly with decreased food intake after irradiation but remained higher than in pair-fed control rats. Plasma lipoproteins were separated by ultracentrifugation on a density gradient (1.006-1.210 g/ml). Four days after irradiation, most of the cholesterol (62% compared to 31% in controls, P < 0.001) is transported by apolipoprotein E-rich high-density lipoproteins. At the same time, plasma levels of apolipoproteins B and E were increased by 28 and 65%, respectively, while those of apolipoproteins AI and AIV were reduced by 21 and 59%, respectively. While in the liver of irradiated rats the apolipoprotein B/E receptor number was not modified, the hydroxymethylglutaryl coenzyme A reductase activity was fivefold higher than in control pair-fed rats. Four days after irradiation, the susceptibility of lipoproteins to peroxidation, as measured by the formation of conjugated dienes in the presence of Cu2+, was markedly increased while plasma vitamin E levels were decreased, demonstrating that irradiation reduces antioxidant stores markedly. These results suggest that such modified lipoproteins could be involved in radiation-induced vascular damage.

Animals↗
PubMed1997

Changes in gut neurotensin and modified colonic motility following whole-body irradiation in rat.

Exposure to ionizing radiation induces gastrointestinal dysfunction often associated with disorders of intestinal motility. Neurotensin is one of the mediators involved in the control of intestinal muscle activity. The aim of this study was to relate neurotensin tissue content and specific receptor binding with contractile effect of neurotensin in rat colon after irradiation. Rats were exposed to whole-body gamma-irradiation (60Co; 6 Gy). Intestinal (caecum, colon) neurotensin-like immunoreactivity, colonic muscle neurotensin receptor binding and neurotensin-induced contractions in isolated colon were investigated 3 and 7 days after irradiation. Irradiation produced a marked increase in the intestinal muscle content of neurotensin-like immunoreactivity (2.5-fold in caecum, 5-fold in colon) 3 days post-irradiation. At 7 days, the intestinal neurotensin content was close to that of the control values. Three days after irradiation, neurotensin receptors in colonic muscle were characterized by the appearance of a transient second class of sites of low affinity-high capacity. A three-fold increase in the total number of sites was observed. In addition, effects of neurotensin on isolated colon preparations showed an increase (37%) of potency but a decrease (7-fold) of efficacy. Seven days after irradiation, the efficacy was close to the control. Modifications of intestinal neurotensin content and specific receptor characteristics induced by irradiation can influence the colonic contractile activity.

Animals↗
PubMed1996

Modulation of gut substance P after whole-body irradiation. A new pathological feature.

Exposure to ionizing radiation induces gastrointestinal dysfunction and inflammatory reactions. The present study carried out in the rat, focuses on substance P, an inflammatory mediator implicated in the control of intestinal motility. We have investigated the effects of gamma irradiation on plasma and tissue substance P levels, ileal smooth muscle activity, and properties of specific receptors. Plasma and ileal (mucosa and muscle) substance P concentrations were measured by radioimmunoassay. At doses ranging from 1 to 8 Gy, plasma substance P levels increased in a dose-dependent manner up to four days after irradiation. Ileal mucosal concentration decreased rapidly 1 hr after a 6-Gy irradiation as compared to controls. A second class of binding sites appeared three days after 6 Gy irradiation. In addition, substance P contractile effects measured on isolated ileum showed a fourfold decrease of EC50, three days after 6 Gy irradiation. These results indicated that gamma irradiation induced an increase of plasma levels concomitant with a modification of gastro-intestinal substance P specific binding sites and contractile activity.

Animals↗
PubMed1996

Exposure to either gamma or a mixed neutron/gamma field irradiation modifies vasoactive intestinal peptide receptor characteristics in membranes isolated from pig jejunum.

The effect of acute whole body exposure to ionizing radiation was investigated on intestinal vasoactive intestinal peptide (VIP) receptors and adenylate cyclase activity in membranes isolated from pig jejunum. Pigs under light anaesthesia were exposed to a single dose (6 Gy) of gamma (gamma) or to mixed neutron/gamma field (ratio 1:1; neutron/gamma) irradiation. Seven days after irradiation, plasma-membranes were prepared from post mortem jejunal mucosal scrapings. Marker enzyme activities (sucrase, leucine aminopeptidase (LAP), Na,K-ATPase) were measured in each preparation. The characteristics (KD, Bmax) of VIP receptors were determined using 125I-labelled VIP. In addition VIP-sensitive adenylate cyclase activity was measured. Results showed that enzyme activities were reduced following both gamma (sucrase 67%; LAP 53%; Na/K-ATPase 29%; N = 7) and neutron/gamma (sucrase 53%; LAP 59%; Na/K-ATPase 68%; N = 5) compared with control values (N = 5). VIP receptor affinity was decreased following either type of irradiation (gamma or neutron/gamma P < 0.01) and receptor numbers increased. Both VIP- and forskolin-stimulated adenylate cyclase activities were reduced but the sensitivity of the enzyme remained the same for VIP (EC50 values (nmol dm-3)-control-1.27 +/- 0.35; gamma-2.18 +/- 0.41; neutron/gamma-1.91 +/- 0.28). In conclusion, exposure to either gamma or neutron/gamma irradiation attenuates intestinal enzyme activities and VIP receptor affinity but increases VIP receptor numbers.

Adenylyl Cyclases↗
PubMed1991

[Evaluation of the quality of life in adulthood of 158 patients surgically-treated for tetralogy of Fallot].

Open heart correction of tetralogy of Fallot is now carried out in infancy. This operation provides children with the best physical and mental conditions for them to complete their education. Until recently, follow-up had been too short to assess the results of repair during infancy in adults. The object of this study was to evaluate the quality of adult life in the first 158 survivors of this surgery, now aged 19 to 36 years, performed in our department since 1968. Ninety eight per cent of these patients are physically capable of leading a normal life; 24% obtained their "baccalaureate" and hold positions of high professional responsibility; 37% achieved basic education diplomas. Even those who left school without qualifications were usually able to find employment. The number of unemployed is less than that of the same age group in the general population. Thirty per cent are married or live with someone, and twenty five per cent have normal healthy children. The large majority have normal active lives. Thirty per cent play sport regularly as a leisure activity. Notwithstanding, all these patients were operated for severe symptoms. Two thirds had had previous Blalock shunts. Severe and persistent cyanosis is not a sign of anatomic severity of tetralogy of Fallot and does not seem to influence the socio-professional outcome. These results are those of what was considered to be high risk surgery at the time because of the inaccuracy of angiographic diagnosis, the inadequacy of myocardial protection and the chronicity of the anatomo-pathological lesions (average age of operated patients was 8 years).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Incidence of residual defects determining the clinical outcome after correction of tetralogy of Fallot: postoperative late follow-up.

The postoperative results in 150 patients who had repair of tetralogy of Fallot (mean follow-up, 10.2 +/- 2.6 years) were defined as good in 71.3%, fair in 20.7%, and unsatisfactory in 8.0% on the basis of clinical criteria. Ninety-six percent of the patients are socially active, 92.0% have a good exercise tolerance, and 79.3% participate in sports. Data from 78 postoperative hemodynamic studies show mild right ventricular dysfunction in almost all patients examined. Peak systolic right ventricular/left ventricular pressure ratio decreased in the postoperative period in 65.4% of patients, remained unchanged in 3.8%, and increased in 30.8%. Minimal residual anomalies can modify the prognosis substantially. Of our patients, 53.3% of those with a shunt (p less than 0.05), 37.5% of those with stenosis (not significant), and 53.8% of those with pulmonary incompetences (p = not significant) have fair or unsatisfactory results. The associated defects are particularly unfavorable. Rhythm and conduction disturbances have resulted in fair or unsatisfactory results in 65.1% of patients. Such a disturbance occurring soon after bypass must be considered an incremental risk factor: 52.9% of patients seen with rhythm and conduction disturbances show the same disturbances later (p less than 0.001).

Adolescent↗
PubMed1986

[Cardiac contusion with dissecting hematoma of the apex of the heart and interventricular communication].

The authors report the case of a post-traumatic ventricular septal defect diagnosed after the detection of a systolic murmur in a 39 year old man, 18 months after a car accident. Two-dimensional echocardiography and angioscintigraphy showed an abnormal cavity at the apex of the heart. At cardiac catheterisation there was a moderate left-to-right ventricular shunt through this cavity. There were no traumatic or atheromatous lesions of the coronary arteries. The operative appearances were of stunned myocardium which had caused a dissecting haematoma of the cardiac apex which ruptured into both ventricular cavities. The lesions were corrected surgically and the systolic murmur disappeared.

Accidents, Traffic↗
PubMed1983

Short-term variations of the right ventricular/left ventricular pressure ratio following repair of tetralogy of fallot.

In 50 consecutive patients undergoing repair of tetralogy of Fallot, the peak systolic right ventricular/left ventricular pressure ratio (pRV/LV) was measured prospectively in the operating room and in the third postoperative week in order to assess its eventual short-term variations. Postoperatively, the ratio fell in 64% of the patients, remained unchanged in 6%, and increased in 30%. The mean postoperative pRV/LV ratio for the group as a whole showed a small but statistically significant fall with respect to the mean operating room pRV/LV ratio (0.47 [standard deviation] +/- 0.16 and 0.52 +/- 0.12, respectively; mean difference, -0.05; p value for the significance level of difference, 0.004). A separate analysis of patients in whom the right ventricular outflow tract was reconstructed with (N = 12) or without (N = 38) a transannular patch showed essentially the same results. Nevertheless, the difference between the pRV/LV ratio measured in the operating room and three weeks postoperatively is not significant in the group with a transannular patch because of the small number of patients. These data corroborate that the pRV/LV ratio measured in the operating room immediately after repair of tetralogy of Fallot reflects closely the postoperative ratio, being slightly higher by an average of 10%, is expected to fall shortly after operation in almost two-thirds of the patients, and is a useful variable in intraoperative decision making and in predicting the surgical result.

Blood Pressure↗
PubMed1982

In vivo study of cholesterol turnover in tissues of adult sows.

The in vivo study of free and esterified cholesterol turnover was carried out in 15 tissues of adult Large White sows maintained at a constant weight for 10-12 weeks. They received a single intravenous injection either of [1-14C] acetate, or of an autologous red cell suspension or of plasma, previously labelled in vitro (for red cells) or in vivo (for plasma) with tritiated cholesterol. The tissues can be separated into four groups according to their relative rate of free cholesterol exchange between plasma and tissues. The liver and the lungs have a very fast exchange rate whereas the brain and the spinal cord have a very slow one. The whole lipoprotein particle transfer--an exclusive model for the esterified cholesterol transport from plasma to tissues--has been found in all sow tissues. When [1-14C] acetate is used as a substrate for cholesterol synthesis, lungs, adrenal glands and heart do not seem--or at an extremely low rate--to convert acetate into cholesterol whereas an intense cholesterol synthesis takes place in the small intestine. Its contribution to cholesterol synthesis in sows--taking into account the cholesterol transfer processes--reaches 70 per cent.

Animals↗
PubMed1981

[Optimal age for the surgical treatment of aortic coarctation. Statistical study on long-term blood pressure values].

UNLABELLED: A retrospective statistical study on late blood pressure in patients operated for coarctation of the aorta have been done, in order to determine the optimum age for elective surgical treatment. Patients were considered hypertensive when their mean blood pressure exceeded the 90th percentile for their age and sex. The series included 126 isolated coarctation of the aortic isthmus operated at the CMC of the Porte de Choisy. The incidence of residual hypertension at rest in the series is as follows: age 1-5: 16,6 %;age 6-10: 34,3%; age 11-15: 47,5 %. In spite of these results there is no significative difference in the incidence by age group. A similar study by the Massachusetts General Hospital on 77 patients showed essentially the same results. A combination of both series (203 patients) which is possible because the study criteria are the same, gives the following results: age 1-5: 11,4 %;age 6-10: 31,9 %; age 11-20: 40,8 %. There is now a significative difference between age group 1-5 and the others (p Less Than 0,02). IN CONCLUSION: the optimum age for elective correction of coarctation of the aorta is 1-5 year. The incidence of residual hypertension is only 11,4 % in that group (70 % confidence limits: 6 to 20%).

Adolescent↗
PubMed1981

[Atrioventricular block disclosing an isolated congenital aneurysm of the sinus of Valsalva, extending into the septum and not ruptured].

A case of a congenital aneurysm of the right anterior sinus of Valsalva (ASV) extending into the septum is reported. The patient, a 20 year old male Central-African, presented with syncopal complete atrioventricular block (AVB) or recent onset. There were no clinical or radiological signs of associated cardiac disease. After implantation of a pacemaker, the diagnosis of an ASV extending into the septum was suggested on routine M mode echocardiography. It was confirmed by two-dimensional echocardiography and aortography. These investigations provided data on its size, its relationship to the cardiac chambers and also showed absence of rupture. The neck of the aneurysm was closed by an endo-aortic approach. There was moderate postoperative aortic regurgitation. This case underlines the value of systematic echocardiography in young patients with AVB of recent onset and obscure origin.

Adult↗
PubMed1977

[Veinous return from the inferior vena cava into the left atrium after surgical correction of Fallot's tetralogy].

A child of 6 presented with a syndrome of gross respiratory distress together with persistant arterial desaturation, requiring ventilation for maintenance of life, occurring after the apparently straightforward correction of a Fallot's tetralogy. Postoperative investigation on the 15th day showed the reasons for the desaturation: there was a massive right-left shunt caused by flow from the inferior vena cava into the auricle of the left atrium through a low atrial septal defect which had not been recognised. Reoperation on the 15th day to close the atrial septal defect corrected the condition satisfactorily.

Child↗
PubMed1976

[Emergency surgical treatment of septal perforations in the acute phase of myocardial infarct. Apropos of 2 cases operated on successfully in the 48th hour and 5th day after development after the necrosis].

The authors report two personal cases of septal perforation during the acute phase of myocardial infarction which under medical treatment would have been rapidly fatal, and which were treated successfully by surgery on the second and fifth days respectively after the infarction, i.e. very early. After briefly recalling the main diagnostic and etiological factors of this serious complication, and the spontaneous prognosis which is usually catastrophic, they emphasise that in presence of poorly controlled heart failure and cardiogenic shock, uncontrollable by intensive medical treatment, only early surgical repair during the first few hours or days of the course of the coronary accident will permit one in certain cases to avoid a fatal issue as proved by their two cases and a review of recent publications. They emphasis the place of circulatory assistance by intraaortic balloon in the preparation of patients for operation and the methods of mycardial revascularisatin during the operation.

Aged↗