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M Mignon

Publications and source records attributed to M Mignon.

At least 91 records · Page 5Linked to original sources
PubMed1995

Evaluation of transferrin-binding protein 2 within the transferrin-binding protein complex as a potential antigen for future meningococcal vaccines.

Because the meningococcal transferrin receptor was shown to elicit bactericidal and protective antibodies in laboratory animals, we undertook a study of the protective role of each of the polypeptides within the Tbp1-Tbp2 complex. We developed a procedure to purify from Neisseria meningitidis B16B6 the two proteins in milligram amounts and raised specific antisera in rabbits and mice. Only antisera specific for Tbp2 displayed bactericidal activity against the parent strain. Mice immunized with purified Tbp2 survived a lethal challenge to a similar degree as animals immunized with the Tbp1-Tbp2 complex, demonstrating that Tbp2 played an important role in the protective activity observed with the complex. Both Tbp1- and Tbp2-specific antisera inhibited transferrin binding to the purified receptor in a solid-phase binding assay, suggesting that the antibodies were able to interact with the Tbp1 molecule only when it was removed from its membrane environment. Finally, Tbp2-specific immunoglobulins were able to lower the growth rate of the meningococci when human transferrin was their sole iron source. Therefore, in all four different systems tested, Tbp2 or antibodies specific for Tbp2 displayed biological characteristics close to those of the Tbp1-Tbp2 complex. This suggests that Tbp2 plays an important role in the protective activity of the complex, eliciting antibodies that are not only bactericidal but also inhibitory for meningococcal growth.

Animals↗
PubMed1995

M or M-like protein gene polymorphisms in human group G streptococci.

Many group G streptococci (GGS) isolated from infected humans (but not from animal sources) express M or M-like proteins with biological, immunochemical, and genetic features similar to those of group A streptococci (GAS). To further elucidate the recently proposed M-like protein gene (emmL gene) polymorphisms in GGS, Southern blots of genomic DNAs from 38 epidemiologically unrelated GGS strains isolated from human specimens and 12 GGS strains recovered from animal sources were hybridized with oligonucleotide probes designed to specifically detect GAS M class I and M class II M protein (emm) genes. All human-associated GGS strains showed DNA homology to the GAS M class I emm gene probe, whereas no hybridization was found with DNA from any of the animal-associated strains. The emmL genes from all human isolates were amplified by PCR, and the complete sequence of the emmL gene of the Rebecca Lancefield grouping strain D166B was determined. Again, this gene exhibited the structural features typical for emm genes of M class I GAS. The 5' regions of the PCR-amplified emmL genes of the remaining 37 human GGS strains were sequenced. This region showed a sequence diversity similar to that known for GAS emm genes. When strains whose N-terminal emmL gene sequences showed a homology of > 95% were defined as belonging to one genetic type, 30 strains were segregated into six distinct genetic types, whereas the remaining 8 strains each exhibited a unique emmL gene sequence. A high degree of homology between the N-terminal emmL gene segments of six GGS strains and the corresponding regions of either the emm12 or the emm57 gene of GAS was found, suggesting a horizontal gene transfer between strains of these species of beta-hemolytic streptococci. Besides a further understanding of the evolution of GGS emmL genes, the observed emmL gene polymorphisms in GGS could provide the basis for a molecular subspecies delineation of strains and offers the potential of typing GGS for epidemiological purposes.

Amino Acid Sequence↗
PubMed1995

Assessment of dysplasia, mucosal mucins, p53 protein expression, and DNA content in ulcerative colitis patients with colectomy and ileorectal anastomosis.

BACKGROUND: Patients with ileorectal anastomosis after colectomy for ulcerative colitis remain at risk of developing rectal malignancy. Detection of mucosal dysplasia has been used for regular screening but is difficult in inflammatory mucosa, prompting the search for complementary markers. METHODS: This prospective study aimed to assess the prevalence of dysplasia, the predominance of sialomucin, DNA aneuploidy, and p53 overexpression as possible predictors of colorectal tumourigenesis, in the rectal mucosa of an unselected group of 27 patients with ileorectal anastomosis performed for ulcerative colitis. Patients had neither neoplastic nor dysplastic lesions on the colectomy specimen and the retained rectum at the time of surgery. One biopsy specimen of each lateral rectal wall was studied, using routine histology, mucin histochemistry, DNA flow cytometry, and the streptavidin-biotin complex method with D07 monoclonal antibodies directed towards the p53 protein. RESULTS: Seventeen, seven, and three patients showed inflammatory lesions of inactive, moderate, and severe active colitis, respectively. Dysplasia, sialomucin predominance, DNA aneuploidy, and p53 overexpression were not detected. CONCLUSIONS: The risk of malignant transformation of the rectal mucosa after ileorectal anastomosis seemed to be low in this ulcerative colitis group without high-grade dysplasia or carcinoma in the previous colectomy specimen, carefully followed up endoscopically and histologically. It remains to be evaluated which of the methods studied above will optimize the histopathologic surveillance of the rectal mucosa of ulcerative colitis patients with ileorectal anastomosis.

Adult↗
PubMed1995

[Effect of prolonged treatment with proton pump inhibitors on serum gastrin levels and the fundus mucosa. Preliminary results].

OBJECTIVES: To evaluate the evolution of fundic argyrophil cell density and hyperplasia grading, fundic chronic gastritis grading and serum gastrin levels in patients treated with proton pump inhibitors. METHODS: Thirty-two patients treated with proton pump inhibitors for gastroesophageal reflux and/or duodenal ulcer were studied. No patient had a gastric ulcer. The studied parameters were serum gastrin levels, fundic argyrophil cell density, the degree of fundic argyrophil cell hyperplasia, the grade of fundic atrophic gastritis and the presence of Helicobacter pylori. The first point of the study was 7 months (range: 0-42 months) and the last point 33 months (range: 7-72 months) after the beginning of the treatment. RESULTS: Serum gastrin levels significantly increased with treatment. Fundic argyrophil cell density did not change significantly. In 3 patients (9%), serum gastrin levels were twice the normal upper limit. The highest serum gastrin levels (249 and 665 pg/mL) were noted in the 2 patients treated with the highest doses of proton pump inhibitors. Micronodular hyperplasia of the fundic argyrophil cells was observed in 2 patients treated with omeprazole 20 mg/d for 4 years and lansoprazole 90 mg/d for 6 years, respectively. Non active superficial chronic gastritis was noted in 2 patients. Serum gastrin levels were significantly correlated with cell densities. CONCLUSION: There were minor modifications of fundic argyrophil cell population and of gastrinaemia during the study period. They were not related to chronic atrophic gastritis. However, survey is mandatory in patients treated with high dose proton pump inhibitors, in those in whom gastrinaemia is elevated and when treatment duration is longer than 5 years.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1995

[Factors of gastroesophageal acid reflux in severe obesity].

OBJECTIVE: To study in morbid obesity the relationship between the degree of gastro-oesophageal reflux (GER) and the excess of body weight, or the related factors such as the energy intake or the fat distribution (waist-hip ratio). METHODS: In 20 morbid obese subjects (body weight: 125 +/- 32 kg) consulting in a weight-loss programme, anthropometric measurements, 3-hr oesophageal pHmetry, double isotope labelled meal for studying gastric emptying, study of gastric acid and pepsin secretions using PEG 4,000 as marker, and upper endoscopy were performed. RESULTS: Nine out of the 20 patients had more than 10 GER per 3-hr period. Seven patients had at least one GER symptom per day. In 6 patients, pH was under 4 for more than 10% of the time. The total number of GER and the number of GER of more than 5 min duration were correlated to the body mass index (P = 0.016 and P < 0.05 respectively). The number of GER was also correlated to the android type of overweight (P < 0.03). These relationships persisted when sex, age, smoking, and obesity complications (such as diabetes) were taken into account. There was a positive correlation between the number of GER and energy and lipid intake (energy intake: 3,119 +/- 1,082 kcal/day; P < 0.003 for both). The degree of GER was positively related to basal acid output (P = 0.049), and to sham feeding-stimulated acid output (P = 0.05); it was negatively related to gastric emptying half time, but was not correlated with basal or stimulated pepsin output. A relationship was found between body mass index (BMI) and gastric emptying half time for solid (P = 0.002) and liquid phases (P = 0.001). CONCLUSION: GER seems to be common in long lasting morbid obesity. The number of refluxes increased with waist/hip ratio, BMI and energy or fat intake. GER was also increased by decreased gastric emptying rate, which was in part determined by BMI. The real prevalence of GER in morbid obeses must be determined by a large prospective study.

Adult↗
PubMed1994

[Zollinger-Ellison syndrome].

Medical management of patients with Zollinger-Ellison syndrome has considerably evolved since initial reports in 1955 and especially over the last decade. Control of gastric hypersecretion by effective antisecretory drugs, accurate localization and staging of the tumoral process by modern medical imaging techniques as well as progress in surgical skill undoubtedly account for higher rates of gastrinoma definitive or long-lasting cure. Elective surgery for gastrinoma removal may indeed be safely undertaken in selected patients. Current diagnostic and treatment strategies have been discussed here, by reference to the literature and a large personal series of patients followed at Bichat-Claude-Bernard Hospital for 30 years. The specific case of gastrinoma associated with multiple endocrine neoplasia type I is also discussed.

Antacids↗
PubMed1994

[Female dyschesia, functional associations and pelvic disorders].

OBJECTIVES: Although the usual methods of exploring anorectal disorders give information on specific aspects of defecation, they do not take into account the related effect of disorders involving the pelvic contents including the genital and urinary tract. We therefore used physical examination and global imaging to demonstrate the effect of urinary and genital anomalies in female patients with dyschesia. METHODS: A prospective study was conducted in 50 consecutive female patients (age range 21-83) who consulted for dyschesia. The following protocol was used. History taking included a search for urinary and gynaecology surgery or medical treatment and the number of pregnancies and instrumental deliveries as well as a precise scoring of defecation disorders. The general physical examination included a search for signs of prolapsus or ulcerations. A rectocolpocystogram was performed in all patients. RESULTS: There were 7 patients under 40 years of age, 25 from 41 to 61 years and 18 over 61. Urinary incontinence was the most frequent functional complaint (80%). In 92% of the patients, the rectocolpocystogram revealed associated anatomic anomalies. Dynamic stimulation was associated with cervicocystoptosis (72%), hysteroptosis (50%) and rectocele (66%). CONCLUSION: Female dyschesia is a complex phenomena involving the anatomic status of the urinary, genital and anorectal tracts. Therapeutic management should be based on a complete examination including an evaluation of the pelvic contents and the perineum.

Adult↗
PubMed1994

Somatostatin receptor scintigraphy in forty-eight patients with the Zollinger-Ellison syndrome. GRESZE: Groupe d'Etude du Syndrome de Zollinger-Ellison.

In patients with the Zollinger-Ellison syndrome, which is either sporadic or integrated into multiple endocrine neoplasia type 1, accurate localization of all the tumours is difficult and may have therapeutic implications. In an attempt to improve this localization, somatostatin receptor scintigraphy using [111In-DTPA-D-Phe1]-octreotide was performed prospectively in 48 consecutive patients with the Zollinger-Ellison syndrome. Thirty of them had the sporadic type of this disease. Scintigraphic data were compared with data obtained by conventional imaging methods, and also, in 32 selected patients, with those obtained by endoscopic ultrasonography. Somatostatin receptor scintigraphy showed abnormal tracer uptake in 39 patients (81%), in whom it correctly identified 50 of the 60 tumoral sites (83%) previously localized by the other imaging methods. In 17 patients (35%) somatostatin receptor scintigraphy disclosed abnormal tracer uptake at 18 different tumoral sites: 14 were located in the abdomen, including four in the liver and eight in the duodenopancreatic area, and four outside the abdomen, including two in the mediastinum. Six of the ten tumoral sites which were not correctly identified by somatostatin receptor scintigraphy were located in the duodenopancreatic area. However, in the 20 patients for whom conventional techniques failed to visualize any tumour in the duodenopancreatic area, somatostatin receptor scintigraphy was positive in ten (50%) whereas endoscopic ultrasonography was only positive in five (25%). In our patients with the Zollinger-Ellison syndrome, somatostatin receptor scintigraphy appeared to be a useful new addition to the battery of tests used for tumour detection.

Bone Neoplasms↗
PubMed1994

Mechanisms of decreased food intake during weight loss in adult Crohn's disease patients without obvious malabsorption.

Because weight loss is common in colonic Crohn's disease and is poorly correlated with disease activity, we analyzed food intake in 63 patients without malabsorption, 30 patients with weight loss (9.2 +/- 4.2 kg), and 33 patients without weight loss. Energy and protein intakes were lower in patients with weight loss than in those with stable weight (P < 0.01). In the former group, food restrictions were more numerous (P < 0.01) and visual analog scales showed less hunger, decreased appetite, and fewer sensations of pleasure related to eating, as compared with the other group (P < 0.01). Food intake reduction was also related to depressive mood and medical advice. However, there was no difference between groups in fecal energy wasting and resting energy expenditure. Weight loss in Crohn's disease may be due to a decrease in food intake rather than to an increase in energy cost of the disease. Thus, focus of attention on the diet is crucial to prevent malnutrition.

Adult↗
PubMed1994

Polymerase chain reaction assay for the detection of Helicobacter pylori in gastric biopsy specimens: comparison with culture, rapid urease test, and histopathological tests.

Ulcer recurrence is probably related to residual Helicobacter pylori (H pylori). Histological examination and culture are considered to be the most specific tests. CLO test is a rapid but less specific test, which is usually used as an alternative test to culture. The aim of this study was to investigate the efficiency of a simplified polymerase chain reaction (PCR) assay as a procedure for the diagnosis of gastric H pylori infection of patients. Biopsy specimens were obtained from antral mucosa of 58 patients at endoscopy and submitted to four tests for detection of H pylori. The bacteria were found in 53%, 43%, 48%, and 50% of patients according to the results of PCR, CLO test, culture, and histological examination. Twenty three patients had both negative histology and negative culture and PCR was negative in all of these. Thirteen patients were not classified because only histology or culture was positive and 10 of these had a positive PCR test. When the diagnosis of H pylori was established by agreement with both histology and culture or three positive tests out of four, 29 patients were H pylori positive (28 having had three positive tests and one displaying positive histology and culture), and 26 were negative, and three undetermined. PCR proved the most sensitive and specific test. These results suggest the simplified PCR assay may be a valuable test for the detection of H pylori.

Adult↗
PubMed1994

[Stenosing esophagitis in Zollinger-Ellison syndrome].

Three patients with the Zollinger-Ellison syndrome and severe oesophagitis are reported. Intractable oesophageal stricture developed, leading to oesophago-gastrectomy in two patients and iterative oesophageal dilatations in the third. The retrospective analysis of these 3 cases led us to recommend, in case of oesophagitis in patients who have or might have the Zollinger-Ellison syndrome, to quickly institute a major antisecretory treatment, by parenteral route if necessary, to precociously and repeatedly control the efficacy of the antisecretory treatment mainly by measuring basal acid output and to avoid unjustified treatment discontinuance and gastric intubations.

Esophageal Stenosis↗
PubMed1994

[Diagnostic and therapeutic strategy of Zollinger-Ellison syndrome. Groupe de Recherches et d'Etudes du Syndrome de Zollinger-Ellison (GRESZE)].

The current strategy recommended for Zollinger-Ellison syndrome (ZES) has significantly improved the outcome of this condition. Diagnosis is based on determinations of basal and post-secretin gastric acid output and serum gastrin levels. A crucial step is differentiation of patients with sporadic ZES from those with multiple endocrine neoplasia type 1 syndrome. Only the former should undergo excision of the tumor when feasible. All available imaging techniques should be used pre- and intra-operatively to detect tumorous lesions. Exploratory laparatomy is warranted in patients who have sporadic ZES without evidence of liver metastases.

Gastric Acidity Determination↗
PubMed1994

[Effect of enprostil on the healing and the recurrence of duodenal ulcer. Comparison with ranitidine].

Enprostil, a synthetic prostaglandin E2, has been shown to exert both antisecretory and mucoprotective activity. It is effective in duodenal ulcer healing. OBJECTIVE--This study was performed to compare the frequency and the delay of spontaneous duodenal ulcer relapse during a two-year follow up period after initial healing by enprostil (35 micrograms, twice a day) or ranitidine (300 mg per day). METHODS--This multicentric, double-blind, randomized study included 642 patients (324 in the enprostil group and 318 in the ranitidine group). Patients included in the follow up period were evaluated by an endoscopy at 6 months, one and two years after healing. RESULTS--After a 6 weeks treatment period, healing rate was 85% for ranitidine and 70% for enprostil, respectively (P < 0.001). Adverse effects, especially digestive ones, occurred more often with enprostil than with ranitidine (P < 0.001). After initial healing, there was no significant difference between the 2 groups concerning the cumulative rate of relapse, despite a non significant trend for a milder rate of relapse in the enprostil group (P = 0.08). Twenty-seven % of the patients randomized to treatment (intend-to-treat analysis) in the enprostil group and 29% in the ranitidine group had no ulcer recurrence 6 months after ulcer healing, and respectively 12% and 13% at 2 years (difference not statistically significant). CONCLUSIONS--It is concluded that a) ranitidine is more effective and has less adverse effects than enprostil for duodenal ulcer healing, b) after duodenal ulcer healing by enprostil, there is a non significant trend for a lower rate of relapse than after healing with ranitidine, c) there is the same proportion of patients without ulcer in the 2 groups after 6 months and 2 years.

Adolescent↗