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A Louvel

Publications and source records attributed to A Louvel.

At least 37 records · Page 2Linked to original sources
PubMed1995

Nonsteroidal anti-inflammatory drug-induced colonic strictures: two cases and literature review.

We report two patients with large bowel submucosal diaphragm disease associated with nonsteroidal anti-inflammatory drugs (slow release form of diclofenac and phenylbutazone) who were admitted in 1990 and 1991 because of iron deficiency. At colonoscopy, the lumen of the ascending colon was divided into compartments by multiple thin circumferential mucosal membranes. Barium enema showed two short strictures in one patient. Right hemicolectomy was carried out on one patient. The other patient was simply advised to discontinue taking diclofenac and remains well. Such lesions are rare (10 cases have been reported) and resemble those previously described in the small bowel.

Aged↗
PubMed1994

Clonal analysis of human adrenocortical carcinomas and secreting adenomas.

OBJECTIVES: Adrenocortical tumours in man are characterized mainly on biochemical, anatomical and histological grounds which establish their secretory pattern and, with some uncertainty, their benign or malignant nature. To study further these tumours and eventually to shed some light on their pathogenesis, we determined their clonal composition. METHODS: Clonal composition was determined by X-chromosome inactivation analysis on tumour and leucocyte DNA using three markers: M27 beta, phospho-glycero-kinase (PGK) and hypoxanthine-phosphoribosyl transferase (HPRT) with 88, 33 and 27% heterozygosity rates respectively. PATIENTS: Clonal analysis was performed on 25 tumours from 19 heterozygous female patients: four had a carcinoma, 14 had a single secreting adenoma, and one had autonomous bilateral macronodular hyperplasia with Cushing's syndrome (seven adenomas examined). RESULTS: The malignant tumours had patterns indicative of monoclonality. The single adenomas displayed contrasting results with patterns indicative of monoclonality in eight cases, and patterns indicative of polyclonality in six cases; monoclonal adenomas were larger and had a higher prevalence of nuclear pleomorphism than the apparently polyclonal adenomas. In the patient with bilateral macronodular hyperplasia, different clonal patterns were present in different adenomas: whereas a clear monoclonal pattern was observed in the three adenomas of the right gland, in which the active X-allele was not always the same, in two interpretable adenomas of the left gland, a moderately skewed pattern suggested a partial monoclonal component. CONCLUSIONS: These data show that adrenocortical carcinomas are monoclonal and suggest that adenomas may arise from a single cell or from more than one cell under the putative action of local growth factors. In adenomas, which until now had appeared homogeneous, this genetic heterogeneity may reflect different pathophysiological mechanisms or it may represent different stages of a common multistep process exceptionally occurring in a single patient with bilateral macronodular hyperplasia.

Adenoma↗
PubMed1992

Chromosome 1 in human colorectal tumors. Cytogenetic research on structural changes and their significance.

The significance of short and long arm anomalies of chromosome 1 was investigated in 55 colorectal tumors comprising 41 carcinomas and 14 adenomas. The tumors were at various stages of transformation from adenoma to carcinoma. Our investigation was prompted by the observation of a p32-pter deletion on the short arm of chromosome 1 in a case of benign tubulovillous adenoma with mild dysplasia, as well as by frequent reports that chromosome 1 is involved in many neoplastic processes. Long arm anomalies were found in seven of the 41 carcinomas, six of which were in stage B2, and short arm anomalies in ten carcinomas at various stages. Three of the adenomas exhibited chromosome 1 anomalies, which in one case comprised a 1p32-pter deletion only. Overall, short arm anomalies especially concerned the p32-36 region. These results suggest that the cytogenetic anomalies respectively located on the short and long arms of chromosome 1 should be considered separately. Damage to the long arm might constitute a late non-specific event, whereas damage to the p32-pter region of the short arm might be involved in triggering colorectal tumor development.

Adenocarcinoma↗
PubMed1991

Disposition and metabolism of acetylcholinesterase reactivators 2PAM-I, TMB4 and R665 in rats submitted to organophosphate poisoning.

1. The dispositions of the acetylcholinesterase reactivators: 2PAM-I, TMB4 and R665, labelled with 14C on the oxime group, have been studied in normal rats and rats poisoned by the organophosphates Soman and A4. 2. For all three compounds, radioactivity was eliminated mostly in the urine (60-90% dose in 24 h). Faecal elimination was low (5.8-17.2% in 72 h). 3. All three compounds concentrated in kidney, but only 2PAM-I and R665 concentrated in liver. TMB4 and R665 concentrated in mucopolysaccharide-containing tissues such as cartilage and intervertebral disc. Other tissues were weakly and uniformly labelled. Soman poisoning does not modify the kinetic parameters of both compounds, but A4 poisoning increases 2PAM-I tissue concentration. 4. Chromatography of urine and plasma showed only unchanged 2PAM-I, TMB4 and R665 in both healthy and poisoned animals. Despite the high concentration of 2PAM-I and R665 in liver, these oximes are not metabolized.

Acetylcholinesterase↗
PubMed1991

[Technique and results of lung transplantation in rats].

Lung transplantation has recently emerged as an efficient therapy for a variety of endstage pulmonary diseases. Nevertheless, many problems remain unsolved. A simple and reproducible experimental model allows examination of some of the problems encountered. We report here our experience of lung transplantation in the rat. One hundred and thirty six lung transplantations have been performed. After the initial phase necessary to master the technique, an overall survival rate of 86% was achieved. Graft function, as assessed by chest X-rays and lung isotope scans, was satisfactory up to 4 months after transplantation. Lung transplantation in the rat is a reliable and reproductible experimental model allowing the development of research projects in this field.

Animals↗
PubMed1991

[Ectasing cholangitis and secondary biliary cirrhosis following intra-arterial hepatic chemotherapy. Treatment by liver transplantation].

A case of ectasing cholangitis, following intra-arterial chemotherapy with discontinuous infusion of fluorouracile, is described. The severe destruction of the intra-hepatic biliary ducts led to the constitution of large cavities in continuity with the biliary tree. These cavities were responsible for images which were mistakenly thought to be metastases. Consequently, secondary biliary cirrhosis developed, requiring orthotopic liver transplantation.

Adenocarcinoma↗
PubMed1990

Clinical features of adrenocortical carcinoma, prognostic factors, and the effect of mitotane therapy.

Adrenocortical carcinoma is a rare tumor, and only limited information is available about its natural history and the effects of therapy. We studied 105 patients (75 female and 30 male; mean age, 46 years) with adrenocortical carcinoma who were referred to us between 1963 and 1987. The average duration of symptoms before diagnosis was 8.7 months. At the time of diagnosis, 68 percent of the patients had endocrine symptoms, and 30 percent had distant metastases. Hormonal studies showed that 79 percent of the tumors were functional. Eighty patients underwent surgery, and 59 also received the adrenal cytotoxic agent mitotane. The median disease-free interval after surgery was 12.1 months (range, 1 to 175). Tumor dissemination occurred in 82 percent of the patients, most commonly to the lung, liver, and adjacent organs. The median survival time was 14.5 months (range, less than 1 to 175), and the five-year survival was 22 percent. Age over 40 years and the presence of metastases at the time of diagnosis were the only factors recognized as indicating a poor prognosis. Mitotane controlled hormonal secretion in 75 percent of the patients. Eight mitotane-treated patients had partial tumor regression, but the drug did not have a significant effect on survival. We conclude that adrenocortical carcinoma carries a poor prognosis. Mitotane therapy may offer transient benefits, particularly in controlling endocrine symptoms.

Adrenal Cortex Hormones↗
PubMed1990

[Xenogeneic hyperacute rejection of the lung in rats].

Xenotransplantation, with organs harvested from appropriate donor animals could be a potential solution to the shortage of donor organs in general and of lung grafts in particular. Unilateral orthotopic lung transplantation in the rat has been used to study the lung xenograft rejection in a discordant donor-recipient combination, i.e. guinea-pig to rat. With this microsurgical technique, a high post-operative survival rate has been reached. The good function of the grafts was assessed by serial chest x-ray, lung perfusion scintigraphy until several months after the transplantation. The survival of the xenografts has been then compared to that of allografts and isografts. Lung xenograft rejection in this combination has been very fast: 53 minutes. Macroscopic and histologic data displayed lung infarct with hemorrhagic edema.

Animals↗
PubMed1990

[Non-functioning tumors of the endocrine pancreas. Concept, diagnosis, treatment].

Five cases of nonfunctioning islet cell tumors of the pancreas are reported. There were 3 males and 2 females aged from 34 to 83 years (Average: 55.8 years). Two tumors were malignant since already metastatic, one tumor was probably malignant and two tumors were judged as benign. One patient died post-operatively. The four remaining patients are alive without recurrence after from 1.4 to 7.3 years. The concepts of nonfunctioning tumors of the pancreas and APUD system are discussed in view of these 5 cases and the relevant literature. The value of tumor markers as well as the radiographic appearances of these tumors are reported. Having a better prognosis than the adenocarcinoma of the exocrine pancreas, the nonfunctioning tumors of the endocrine pancreas are best managed by surgery. The indications and the results of surgery and chemotherapy are discussed.

Adenoma, Islet Cell↗
PubMed1989

[Primary hyperaldosteronism caused by unilateral macronodular hyperplasia].

A case or primary hyperaldosteronism due to unilateral macronodular adrenal hyperplasia is presented. This entity is exceptional: a review of the literature has yielded only three similar cases. The significance of these adrenal nodules is discussed; in particular, they are compared with the nodules found in hypertensive subjects. Their course after surgery is similar to that of Conn's adenoma.

Adrenal Gland Diseases↗
PubMed1989

In vivo MR spectroscopic imaging of the adrenal glands: distinction between adenomas and carcinomas larger than 15 mm based on lipid content.

The usefulness of MR spectroscopic imaging for discriminating between lipid and water was applied to the in vivo differentiation of adrenal adenomas from carcinomas. By using the Dixon sequence in 20 patients, the lipid content of 22 adrenal tumors larger than 15 mm was determined. The mean percentage of lipid in 15 adenomas was 13.4% (standard deviation, 8%), compared with 3.5% lipid (standard deviation, 2%) in seven carcinomas. Only one lesion would have been misclassified on the basis of in vivo measurements of lipid content. After surgery, in vitro MR spectroscopy was used to determine the percentage of lipid in excised samples of nine of the 22 tumors. These in vitro measurements confirmed the in vivo results on lesions larger than 20 mm in diameter. Respiratory artifacts appeared to decrease the accuracy of in vivo measurements in smaller lesions. In vivo MR spectroscopic imaging of adrenal tumors appears to be useful for differentiating between adrenal carcinomas and adenomas.

Adenoma↗
PubMed1988

Tubulovillous adenoma of the colon with hyperdiploidy, double-minute chromosomes, and inversion of chromosome 1.

A sessile adenoma of the left flexure of the colon was studied after surgical colectomy. Specimens were obtained for complete histologic evaluation. The tumor consisted of glandular tubes with decreased mucin production and a papillary structure on the luminal aspect. The muscularis mucosa was not involved; there was no carcinomatous focus. Cytogenetic study was carried out on 56 cells; none was normal, 77% were hyperdiploid (52-87 chromosomes), 16% were hypodiploid (18-39 chromosomes), and 7% were paradiploid. The supernumerary chromosomes were chromosomes #3, #6, #13, #19, and #20; chromosome #18 was missing in 80% of the cells. A marker for chromosome #1 resulting from a q21.1-q21.2 break with inversion of the centromere-bearing segment (pter-q21) was observed in 58% of the cells. Twenty-five percent of the cells had double minute chromosomes. Despite the histologically benign nature of the tumor, all the cells showed significant cytogenetic aberrations, some of which are considered to be markers of neoplastic transformation (polyploidy, double minutes, chromosome #1 marker).

Adenoma↗
PubMed1988

Hepatocellular carcinoma after danazol therapy.

Danazol, an inhibitor of pituitary gonadotropin, has been proposed in the treatment of systemic lupus erythematosus (SLE). We report the case of a female patient with SLE in whom a hepatocellular carcinoma was discovered after 4 years of treatment with danazol. Except for 3 days of hypochondrium pain, there were neither clinical signs of liver tumor nor biological abnormalities. An ultrasonography showed 2 tumors of the liver. At histological examination after surgery, one of the tumors was found to be a benign adenoma, while the other was a well differentiated hepatocellular carcinoma. When longterm danazol therapy is required, ultrasonography may be useful for early tumor detection.

Adenoma↗