PubMed Health⌕ Search

Biomedical subjects

C Breton

Publications and source records attributed to C Breton.

84 records · Page 5Linked to original sources
PubMed1979

[Epidemiological profile of patients with myocardial infarction and normal coronary arteriography].

Of a total of 4,800 coronary arteriogrammes, 1,280 of which were carried out after myocardial infarction, 25 cases of proven infarction with normal coronary arteriography, confirmed by several "blind" interpretations, were retained. The interval between acute infarction and coronary arteriography was usually less than 6 months. The average age of the patients was 36.9 years, affecting more women than in classical coronary artery disease. The acute infarction was nearly always the first symptom. Cigarette consumption and hormonal factors is women were coronary risks factors of note. Ventricular sequellae were frequent, cardiac failure exceptional, exercise testing nearly always negative and occupational rehabilitation usually normal. It would seem that this affection is less serious than classical myocardial infarction due to atheroma probably because the non-infarcted myocardium is healthy, but the true prognosis of this type of coronary accident will only be revealed by long term studies. In the meantime the most useful investigations and the management of these patients are discussed.

Adolescent↗
PubMed1979

[Hemodynamic effects of normovolemic hemodilution].

After reviewing data from the literature concerning the effects of normovolaemic haemodilution on cardiac output and regional flow rates, the authors illustrate these concepts by a personal study involving the haemodynamics of 10 subjects undergoing operation in normovolaemic haemodilution. Removal of blood was compensated simultaneously by modified liquid gelatin in electrolytic solution (Plasmion) until the haematocrit was 0.30. Measurements were performed before haemodilution in patients in a steady state (anaesthetised, intubated, normoventilated), at the end of haemodilution, at the end of the operation, then 4 hours after recovery. There was no variation in blood pressure and heart rate, showing that normovolaemia was maintained. At the end of haemodilution, cardiac index increased from 3.10 to 3.84 l.min-1.m-2 (0.0517 to 0.0638 l.s-1 . m-2) (p < 0.005); stroke volume increased from 70 to 83 ml (p < 0.005); systemic resistance fell from 1585 to 1262 dynes. s.cm-5 (158.5 to 130.4 kPa.s.l-1) (p < 0.005); arterial oxygen content decreased from 191.1 to 152.1 ml.100 ml-1 (8.535 to 6.793 mmol.l-1) (p < 0.005), whilst oxygen transport was unchanged. These various haemodynamic measurements showed no significant changes at the subsequent times when they were measured, values remaining close to those obtained at the end of haemodilution. The results confirm the fact that norvolaemic haemodilution is accompanied by a fall in systemic vascular resistance with an increase in cardiac output. Regional circulations are thus improved. Since oxygen transport is unaffected, the oxygenation of peripheral tissues is ensured normally.

Biological Transport↗
PubMedDate not supplied

[Conformal radiotherapy of brain tumors].

Conformal irradiation of brain tumours is based on the three-dimensional reconstruction of the targeted volumes and at-risk organ images, the three-dimensional calculation of the dose distribution and a treatment device (immobilisation, beam energy, collimation, etc.) adapted to the high precision required by the procedure. Each step requires an appropriate methodology and a quality insurance program. Specific difficulties in brain tumour management are related to GTV and CTV definition depending upon the histological type, the quality of the surgical resection and the medical team. Clinical studies have reported dose escalation trials, mostly in high-grade gliomas and tumours at the base of the skull. Clinical data are now providing a better knowledge of the tolerance of normal tissues. As for small tumours, the implementation of beam intensity modulation is likely to narrow the gap between conformal and stereotaxic radiotherapy.

Brain Neoplasms↗
PubMedDate not supplied

[Curietherapy in uterine cervix cancers: what therapeutic trends?].

Brachytherapy is a fundamental step in the treatment of patients with cervical cancer. Brachytherapy allows a significant increase in the local control rate as well as the survival rate. Brachytherapy has to be performed as soon as possible after external irradiation in order to maintain the overall treatment time below 53 days. Technical and dosimetric data characterizing low dose-rate brachytherapy using ICRU 38 recommendations have led to an improvement in local control and a decrease in complications. Data are less well known for other dose rates. The role of interstitial brachytherapy is not clearly defined and its potential benefit is probably balanced by an increase in severe complications. Concomitant brachy-chemotherapy requires further clinical investigations, even if concomitant radio-chemotherapy has become a standard in advanced cervical cancers.

Antineoplastic Agents↗
PubMedDate not supplied

Vasopressin : a potent autocrine/paracrine regulator of mammal adrenal functions.

The control of adrenal functions by locally secreted neuropeptides or neurotransmitters is of great physiological importance. Vasopressin (VP) is one of these autocrine/paracrine regulators. We demonstrated by RT-PCR and perifusion experiments that rat and human adrenal medulla expressed and released vasopressin under basal conditions and under stimulation by acetylcholine. Intra-adrenal concentrations of VP may be sufficient to activate adrenal VP receptors. In the cortex, only the V1a receptor subtype has been detected. It triggered both steroid secretion and cortical growth. In the medulla, both V1a and V1b receptor subtypes were expressed. V1b receptors were mainly present on chromaffin cells and stimulated catecholamine secretion. The role of the V1a receptor remains unclear. Pathophysiological studies also revealed that human pheochromocytoma did not overexpress vasopressin receptors but might oversecrete vasopressin causing high plasma VP concentrations and elevated blood pressure.

Adrenal Glands↗
PubMedDate not supplied

Intraperitoneal chemohyperthermia for peritoneal carcinomatosis: original modeling, clinical tolerance and results study about 30 patients.

BACKGROUND/AIMS: The authors' objective is to report their experience of the intraperitoneal chemohyperthermia after a thermal modeling study which has allowed the optimization the intraperitoneal chemohyperthermia circuit and its running parameters and to evaluate the intraperitoneal chemohyperthermia tolerance. Intraperitoneal chemohyperthermia is considered more and more as an interesting therapeutic option in cases of some abdominal carcinomatosis, particularly of digestive origin. However, the main technical problem of this treatment is the homogenization of the temperature distribution in the abdominal cavity. METHODOLOGY: A thermal modeling has allowed us to finalize a reliable and well-tolerated intraperitoneal chemohyperthermia technique. The achievement of a physical model of the abdomen has allowed us to make an experimental study of the temperature distribution in a given liquid volume. Two steps were carried out. The first step was the characterization of the model with a thermal study carried out on the physical model and which has led to dynamic data about the heat balance leading to a knowledge model. The second step was the identification of a theoretical model of the thermal behavior which would correlate best with the experimental data. Between January 1995 and January 1998, 30 patients with peritoneal carcinomatosis were studied. Twenty-six patients underwent maximal cytoreductive surgery with abdominal evisceration, intraperitoneal chemohyperthermia. Intraperitoneal chemohyperthermia was carried out for 1 hour, at 42 degrees C, with a flow rate of 0.9 L/min in the 30 patients. The thermal modeling has shown the main purpose of a high flow rate of 0.9 L/min in the homogenization of temperature distribution. RESULTS: The 2 steps are shown to converge. This coherency between the 2 models proves that the thermal aspects of the process have been properly identified. Our initial results have shown that intraperitoneal chemohyperthermia was properly tolerated. Major intraoperative complications occurred for 1 patient. CONCLUSIONS: The experimental study with thermal modeling results should help to optimize the intraperitoneal chemohyperthermia circuit and its running parameters for human treatment, with an acceptable morbidity in 30 patients.

Adolescent↗
PubMedDate not supplied

Immunogenicity of Plasmodium falciparum antigenic determinants produced by Escherichia coli recombinant clones.

The immunogenicity of two parasite antigens produced by Escherichia coli as proteins fused to beta-galactosidase was investigated in three animal species: mice, rabbits and squirrel monkeys. 2L protein carries 71 amino acids of a parasite antigen and 11.1 protein carries 23 repeats of a 9-amino-acid repetitive unit. The humoral response was studied using indirect immunofluorescence and immunoprecipitation. The results indicate that immunization of mice, rabbits and squirrel monkeys using SDS-denatured 2L fusion protein induced antibodies able to bind to parasite antigen 2L in the IFA or in the immunoprecipitation assays. Immunization using the native fusion protein did not induce antibodies able to immunoprecipitate the 2L parasite antigen. The same observation was made for the animals immunized with 11.1 recombinant protein. In this case, the antibody response was also measured by ELISA using synthetic dimers of the repeat as antigen. In mice and rabbits, high titres of anti-11.1 antibodies were found by ELISA. However, when the antigen produced by the parasite itself was used to evaluate the response, low titres were found. This indicates that the animals produced high levels of antibodies to a structure which is not exposed in the parasite. In squirrel monkeys, the same observation was made, but the overall levels of the response to 11.1 antigen were considerably lower than those observed in mice or rabbits.

Animals↗
PubMedDate not supplied

[Duration of action of trandolapril in mild to moderate hypertensive patients evaluated by ambulatory measurement of blood pressure].

The duration of the antihypertensive action of transdolapril, a new angiotensin converting enzyme inhibitor, was studied in 23 patients using ambulatory blood pressure monitoring (ABPM) over 48 hours. After a 20-day placebo period (D1 to D20), mild to moderate hypertensive patients received 2 mg trandolapril once daily for 30 days (D21 to D50). The first 24-hour ABPM recording was performed on day 14, during the placebo run-in period. Two additional recordings were done successively on days 50 and 51 corresponding to a normal dosing day and a following day with a simulated missed dose, respectively. The three blood pressure recordings (placebo, treatment, missed dose) were compared. The average 24-hour systolic (SBP) and diastolic (DBP) blood pressure were significantly decreased by trandolapril. The mean +/- s.d. decrease between day 14 and day 50 were - 8.0 +/- 7.2 mmHg for the DBP and -13.3 +/- 7.8 mmHg for the SBP. Blood pressure was also consistently decreased during the daytime period (-8.7 +/- 7.9 mmHg for the DBP and - 15.6 +/- 8.5 mmHg for the SBP), nighttime period (-5.6 +/- 9.1 mmHg for the DBP and - 8.5 +/- 11.3 mmHg for the SBP) and early morning (- 12.3 +/- 9.7 mmHg for the DBP and - 15.9 +/- 15.1 mmHg for the SBP). The normal circadian pattern of blood pressure was maintained under treatment. The antihypertensive effect of trandolapril was sustained beyond 24 hours after the last intake: there were no significant difference beetween days 50 and 51 in terms of 24-hour, daytime and nighttime average blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Ambulatory Care↗
PubMedDate not supplied

[Azygo-portal disconnection by the abdominal route].

Azygo-portal disconnection by the abdominal route consists of devascularization of the lower oesophagus, cardiac orifice and greater gastric tuberosity by ligation of the varices and section of the oesophagus, combined in every case with truncular vagotomy and gastric bypass. In emergencies the abdominal approach enables the bleeding points to be accurately localized. In the treatment of haemorrhages due to portal hypertension, this technique offers an alternative to porto-caval bypasses when these cannot be performed (thrombosis or portal cavernoma) or when the risk of encephalitis is too high. However, contrary to liver transplantation, it is a palliative technique for cirrhotic patients.

Abdomen↗