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P Lointier

Publications and source records attributed to P Lointier.

At least 19 recordsLinked to original sources
PubMed1997

[Segmental absence of colonic muscularis propria. Report of a case in an adult].

We report a case of segmental defect of colonic muscularis propria revealed by perendoscopic perforation in a 64-year-old woman. Segmental absence of intestinal musculature is well documented in new-borns and infants and is more frequent in small bowel. It is characterized by localised absence of muscularis propria without fibrous scar. The remaining layers of the bowel wall are intact. The pathogenesis of this lesion is discussed.

Colon↗
PubMed1996

[Hepatic hamartoma in adults. Apropos of a case documented by MRI].

A mixed hamartoma of the liver in a 39 year old man is reported. Abdominal ultrasound revealed a 4 cm inhomogeneous echogenic mass with acoustic shadowing. MRI T1 weighted images showed a inhomogeneous low intensity mass with lower gadolinium enhancement than normal liver, a moderate low signal intensity on proton density weighted images, and heterogeneous isosignal intensity on T2 weighted images. Peripheric calcifications were found on pathologic examination.

Adult↗
PubMed1994

Adenocarcinoma of the duodenum: factors influencing survival. French Association for Surgical Research.

The records of 66 patients with histologically proven adenocarcinoma of the duodenum were reviewed retrospectively to determine factors influencing survival. The parameters studied were age, sex, weight loss, jaundice, anaemia, duodenal stenosis, type of surgical procedure, tumour size and location, depth of parietal invasion, presence and location of lymph node metastases, and pancreatic invasion. These factors were assessed in a group of 46 patients who underwent curative resection of the tumour; 20 patients who received palliative procedures were excluded from statistical analysis. Survival curves were established by the Kaplan-Meier method and compared by the Mantel-Haentszel test. The actuarial 3- and 5-year survival rates of patients undergoing curative resection were 59 and 45 per cent respectively. None of the prognostic factors studied influenced survival. These results indicate that resection of adenocarcinoma of the duodenum should be performed whenever possible, even in the presence of lymph node metastasis and pancreatic spread.

Adenocarcinoma↗
PubMed1994

Human breast and colon cancers exhibit alterations of DNA methylation patterns at several DNA segments on chromosomes 11p and 17p.

In breast and colon adenocarcinomas methylation patterns at CCGG sites of several loci located on the short arm of chromosome 11 were determined by Southern blot analysis. Results obtained indicate that all tumor samples (20/20) exhibit DNA methylation changes when compared to their normal counterparts. In colon tumors, gamma-globin gene is usually hypomethylated (9/10), whereas Ha-ras gene, which is located in the same region, retains an unmodified DNA methylation pattern. Hypomethylation of parathyroid hormone (5/10) and catalase genes (4/10) are also frequently detected in colon tumor specimens. For the catalase gene the region around exon 2 is the only one which is affected by these changes. In breast adenocarcinoma, modifications of the methylation patterns are less frequently observed. However, hypomethylation of the gamma-globin gene is a very common event in these tumors (8/10), and it is also detected (2/2) in lobular carcinoma in situ which is an early step in breast tumorigenesis. In addition, hypermethylation of a CpG island is also observed at the locus 17p13.3 in both colon (5/5) and breast (4/9) adenocarcinomas. In the tumoral tissues analyzed these hypermethylations are not associated with the hypermethylation of the 5' flanking sequences which contain a limited amount of CpG. Some of these alterations seem, therefore, to be tumor and sequence specific.

Adenocarcinoma↗
PubMed1993

Characterization of the DiFi rectal carcinoma cell line derived from a familial adenomatous polyposis patient.

The DiFi human colorectal cancer cell line was recently established from a familial adenomatous polyposis patient with extracolonic features characteristic of the Gardner syndrome. These cells have now been propagated for 150 passages in standard culture media and vessels without feeder layers or collagen coatings. They retain features of colonic epithelial cells such as surface microvilli, secretory vesicles, and desmosomes. Cytosol of DiFi cells contains a high level (502 U/mg protein) of the mucin CA 19-9. In addition, DiFi cells produce carcinoembryonic antigen, and induce tumors in athymic mice. Cytoskeleton analysis of DiFi cells by fluorescence microscopy showed a pronounced disorganization of actin cable structure. The isozyme genetic signature of DiFi cells is unique (0.01 probability of finding the same genetic signature in a different cell line), differs from that of HeLa cells, and has expressional features seen in other colorectal cell lines. The DiFi cell karyotype is tetraploid, contains many marker chromosomes, and shows numerous episomal particles. Two copies of chromosome 18 were absent, and only a single normal chromosome 17 was found. This parallels detection of allelic losses from DiFi cell DNA at loci on chromosomes 17p and 18 using molecular (cDNA) probes. DiFi cells clearly express transcripts for the c-myc proto-oncogene, the c-myb proto-oncogene, and the p53 tumor suppressor gene. Transforming growth factor beta inhibits DiFi cell growth in soft agar and suppresses c-myc expression in these cells. The value of this cell line in the study of genetic alterations in colorectal cancer is discussed.

Actins↗
PubMed1993

Thoracoscopic dissection of the esophagus in human cadavers.

A technique for thoracoscopic dissection of the esophagus is described which gives a large and magnified view of the pleural cavity, the mediastinum, and the esophagus. This technique was developed on human cadavers which gives excellent technical resources for learning and practicing endoscopic surgical anatomy of the esophagus. It avoids the need to change the position of the patient to perform a total thoracoabdominal esophagectomy via a triple surgical approach.

Azygos Vein↗
PubMed1993

A technique of laparoscopic gastrectomy and Billroth II gastrojejunostomy.

This report describes a technique of total intraabdominal laparoscopic gastrectomy using laparoscopic stapling and suturing. The reestablishment of continuity of the upper gastrointestinal tract was performed by gastrojejunostomy (Billroth II) using the Endo GIA stapler. This procedure merits inclusion in the armamentarium of approaches toward surgical treatment of recurrent gastric ulcer.

Anastomosis, Surgical↗
PubMed1993

Laparoscopic-assisted perineal rectosigmoidectomy with pullthrough.

We report for the first time the treatment of an early rectal cancer by laparoscopically assisted rectosigmoidectomy with pullthrough. The low colorectal anastomosis was constructed using a double-stapling technique. We believe that this procedure might offer a promising new option for the treatment of midrectal cancer with sphincter saving. Further investigation is recommended.

Adenocarcinoma↗
PubMed1993

[Subtotal colectomy under celioscopy].

Indications for laparoscopic surgery of digestive disease are increasing in scope and now include colorectal affections. A technique for subtotal colectomy with ileorectal anastomosis under laparoscopic control is described.

Anastomosis, Surgical↗
PubMed1991

Status of sex steroid hormone receptors in large bowel cancer.

To determine the potential role of sex steroid hormones in the development of colorectal tumors in humans, specific androgen (AR), estrogen (ER), and progesterone (PGR) receptors were investigated in normal mucosa (NM) and in tumor (T) paired biopsy specimens from 94 patients. Androgen receptors were detected in 98% and 96% of NM and T samples, ER in 91% and 83% of NM and T biopsy samples, whereas PGR were detected only in 14% and 10% of NM and T specimens, respectively. These incidences are independent of the sex and age of the patients. They are not related to tumor localization, histologic grade, or stages of Dukes' classification. Scatchard analysis of labeled ligand binding indicated the existence of one single class of high affinity binding sites; the calculated dissociation constant (Kd) was 1.7 +/- 0.6 10(-9) molar concentration (M) for 5 alpha-dihydrotestosterone (DHT) and 0.6 +/- 0.3 10(-9) M for estradiol (E2). These values were identical in NM and T tissue for both AR and ER. The binding capacity for DHT was 148 +/- 67 and 93 +/- 43 fmol/mg of cytosol protein in NM and T tissues, respectively (P less than 0.05). The ER content was lower and similar in NM and T biopsy specimens: 19 +/- 9 and 18 +/- 10 fmol/mg protein, respectively. The PGR content was 10 +/- 4 in NM versus 17.5 +/- 6 fmol/mg protein in T specimens. It is observed that the elevated AR in normal mucosa is not related to any known function for androgens in the digestive tract. The receptor pattern observed in tumors does not support the hypothesis previously raised in the case of chemically induced colonic tumors in rodents.

Adenocarcinoma↗
PubMed1991

Sex steroid and 1,25-dihydroxyvitamin D3 receptors in human colorectal adenocarcinoma and normal mucosa.

In order to determine the potential role of sex steroid and 1,25-dihydroxyvitamin D3 in the spreading of colorectal cancer, previously hypothesized from epidemiological and experimental data, specific androgen (AR, n = 94), estrogen (ER, n = 60), progesterone (PGR, n = 50), and 1,25-dihydroxyvitamin D3 receptors (VDR, (n = 111) were investigated in human colorectal adenocarcinoma (AC) and compared with the normal adjacent mucosa (NM). Scatchard analysis and competition studies of binding data did not reveal any difference between the biochemical behavior (affinity, specificity, and sedimentation coefficient) of the normal and tumoral tissue receptors. For ARs and ERs, high incidences were found (92 of 94 and 90 of 94 in NM versus 46 of 60 and 40 of 60 in AC, respectively) in both classes of tissues, while they were low for progesterone (7 of 50 and 5 of 50 in NM versus AC). While for sex steroid receptors the incidences did not vary with sex and age of the patients or the location and histopathological grade of the tumor, the VDR incidence was lower in AC (35 of 111) than in NM (99 of 111) and decreased significantly from the right colon to the rectum in adenocarcinoma. Binding capacities were similar in NM and AC for ERs and VDRs, whereas AR levels in NM were significantly higher than in AC. The expression of VDRs in some colorectal tumors suggests a possible clinical significance. No known function for sex steroid receptors is related to their presence in human colorectal tissues and their pattern in carcinoma does not support any hypothesis previously raised in the case of chemically induced colonic tumors in rodents.

Adenocarcinoma↗
PubMed1991

1,25-Dihydroxyvitamin D3 receptors and human colon adenocarcinoma.

Epidemiological evidence suggests that dietary calcium and 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) might have a protective effect against colorectal cancers. Since the presence of receptors is required for steroid action, specific 1,25-(OH)2D3 receptors (RD3) were investigated in biopsies taken at different levels of the colon. The study involved 90 biopsies from patients operated on for colorectal adenocarcinoma. They were paired biopsies from adenocarcinoma tissue and adjacent normal mucosa. In addition, 26 normal intestinal mucosa biopsies from patients without cancer were examined. RD3 receptors were assayed in tissue extract by the dextran-coated charcoal technique and also characterized by sucrose density gradient sedimentation. Scatchard analysis showed a single class of specific high affinity-low capacity sites binding for 1,25-(OH)2D3. The incidence of RD3 was 86 per cent in normal mucosa (n = 77) and lower in carcinoma (n = 34), for which the incidence decreased significantly (P less than 0.001) from right colon (58 per cent) to left colon (37 per cent) and rectum (19 per cent). These data suggest that the normal colon is a potential target organ for 1,25-(OH)2D3 which might modulate calcium transport in the colon. Loss of receptivity to 1,25-(OH)2D3 is associated with malignant transformation.

Adenocarcinoma↗
PubMed1990

[Hepatic alveolar echinococcosis: diagnosis and treatment].

Alveolar echinococcosis is a parasitic disease which is relatively rare in humans. It almost exclusively affects patients of rural origin living in enzootic regions (Eastern France, Auvergne) and most lesions are in the liver. Several anatomico-clinical forms have been described; the most frequent is the multilocular form, but the disease may consist of one single cyst or abscess. The liver structure is always deeply altered, with compression, inflammation or superinfection. Jaundice, liver enlargement, abdominal pain or signs of secondary localizations are manifestations that lead to the discovery of hepatic alveolar echinococcosis. The anatomical features of the lesions are demonstrated by ultrasounds and computerized tomography. The main differential diagnosis is tumoral pathology of the liver. In most cases the diagnosis of echinococcosis is confirmed by serological tests, although needle or even surgical biopsy might be necessary. Diagnosed at an early stage, alveolar echinococcosis can be amenable to surgical treatment (hepatectomy), and liver transplantation may even be performed. Medical treatment with benzimidazoles seems to be promising.

Albendazole↗