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R Michiels

Publications and source records attributed to R Michiels.

At least 19 recordsLinked to original sources
PubMed1991

Report of a primary lymphoma of the conjunctiva. A lymphoma of MALT origin?

A case of primary conjunctival lymphoma is reported herein. A 47-year-old woman presented with an indolent salmon-coloured tumour of the lower epibulbar conjunctiva. Histologically, we found a lymphoid infiltrate in the epithelium and subepithelium consisting of two components. One component was characterized by centrocytic-like cells and the other by lymphocytic, plasmacytoid and plasma cells. An immunohistological study demonstrated a light chain restricted immunoglobulin expression of the tumour cells as well as some residual polytypic follicles exhibiting reticular dendritic cells. Tumour cell proliferation was associated with a T cell reactive population. A comprehensive investigation (in particular an orbital scan) did not demonstrate any other localization of this lymphoma. Such a lesion raised the question of a possible MALT origin, by analog with MALT-lymphomas of the gastrointestinal tract described by Isaacson and colleagues.

Antibodies, Monoclonal↗
PubMed1991

[Production of a monoclonal anti-Cryptosporidium sp. antibody for paraffin-embedded sections].

Since the development of acquired immunodeficiency syndrome, human Cryptosporidiosis has received increased attention. A provisional histological diagnosis can be made on gastrointestinal tract biopsy specimens by light microscopy by showing small round organisms of 2-5 microns attached to the epithelial cell apex. The definitive diagnosis of certitude can only be made by electron microscopy with the identification of various developmental stages of the parasites. We have produced a monoclonal antibody specific to Cryptosporidium sp. usable in paraffin-embedded tissue sections. Such a monoclonal antibody would be an important tool for histological diagnosis of human Cryptosporidiosis.

Acquired Immunodeficiency Syndrome↗
PubMed1990

[A case of liver angiosarcoma arising in a pre-existing cavernous hemangioma].

A 36-year-old woman presented with a solitary hepatic tumor. Macroscopically, the tumor measured 9 cm in greatest diameter, and was well encapsulated; it was reddish, and showed multiple foci of hemorrhage. Microscopic examination revealed two different patterns: a peripheral angiosarcoma surrounding a centrally located cavernous haemangioma. To our knowledge, such an entity has not been reported up to now. Possible pathomechanisms, radiological and pathological findings of this angiosarcoma of liver arising within a cavernous haemangioma are commented.

Adult↗
PubMed1990

[Is the Tru-Cut needle more efficient than the fine needle in the diagnosis of hepatic lesions? Comparative study of 45 echography-guided punctures].

A comparison of diagnostic efficiency of fine needle biopsy (22 G) versus coarse needle biopsy (Tru-Cut 14 G) was performed on ultrasound-guided liver biopsies in 45 patients. Diagnosis was established through clinical, paraclinical and pathologic features. For each patient pathologic examination of both fine needle biopsy (cytology and histology) and coarse needle biopsy (histology) were performed by a pathologist unaware of any clinical data. Of 36 malignant tumors, diagnosis of malignancy was made in 83 percent of the cases by fine needle biopsy and in 81 percent of the cases by Tru-Cut biopsy, and distinction between primary and secondary cancer, in 83 and 86 percent of cases respectively. Specificity was 100 percent with both techniques. Of 9 benign lesions, the 6 focalized fatty infiltrations were diagnosed by both fine and coarse needle biopsies. As fine needle biopsy is less invasive than coarse needle biopsy and gave equally satisfying results, we suggest that it should be used preferentially in the diagnosis of focalized liver lesions.

Biopsy, Needle↗
PubMed1990

[Epilepsy and bilateral occipital calcifications: 3 cases].

We report 3 cases of epilepsy with bilateral occipital calcifications followed up for several years. These cases were compared with 21 published cases and were found to differ from the classical Sturge-Weber syndrome on several points: 1) the disease appeared around the age of 5 years and consisted of focal epilepsy without neurological or mental disorders; 2) the epilepsy was easy to control during 2 to 5 years. This was followed by a diffuse encephalopathy with severe, treatment-resistant epilepsy, Gerstmann's syndrome, optic ataxia, cerebellar syndrome and slow activity at EEG. It appears from these 3 cases that: 1) occipital calcifications may be unilateral at the onset of the disease; 2) visual evoked potentials are affected at a late stage, and 3) CT scans are of considerable value in the prognosis of benign epilepsy in childhood.

Brain Diseases↗
PubMed1990

[Favorable outcome of Wegener's disease limited to the lungs. Apropos of a case].

A case of Wegener's granuloma limited to the lungs is reported in a 22 year old man. The pulmonary radiograph showed bilateral nodules. A lung biopsy of a nodule revealed a necrosing vasculitis involving the arteries and the veins and some areas of necrosis in geographical contours around these vessels. The renal function was normal and 4 1/2 years later the outcome remains favourable with the minimum of treatment, the exception being a course of antibiotics post operatively. Fifty seven cases of Wegener's granuloma limited to the lungs have been diagnosed after lung biopsy, transbronchial or bronchial material. The outcome was favourable in 72% of cases. This result was observed in the absence of any treatment in 6 cases (13%). In 2 cases the pulmonary nodules disappeared or developed cavities. In 4 cases the anatomical and/or radiological progress is unknown. Currently the factors leading to such an outcome have not yet been identified.

Adult↗
PubMed1989

CD 15 antigen in Hodgkin's disease.

A retrospective analysis of 117 cases of Hodgkin's disease treated at the Centre G.F. Leclerc between 1976 and 1985 was performed with three objectives: 1): to re-evaluate the histologic subtype by the Lukes-Rye classification according to recent data; 2): to demonstrate the frequency of CD 15 antigen by an indirect, three stage immunoperoxidase technique on initial node biopsy histologic sections; 3): to study the prognostic value of this antigen. Histologic reclassification disclosed that 9 cases were in fact non Hodgkin's lymphoma. The remaining 108 cases were classified as lymphocyte predominant (n = 11), nodular sclerosis (n = 77), and mixed cellularity (n = 17), with no cases of either lymphocyte depletion or nodular paragranuloma of Poppema and Lennert identified. In these specimens, fixed in Bouin's solution and embedded in paraffin, CD 15 antigen was detected in the Reed-Sternberg cells and the mononuclear variety of Hodgkin cells in 64 patients (59%). The presence of this antigen was independent of histologic subtype, patient age or sex, clinical stage and the presence of systemic symptoms. Both actuarial disease-free and overall survivals showed that the prognosis of Hodgkin's disease is more favorable in CD 15 positive cases.

Antigens, Differentiation↗
PubMed1989

Subcellular localization of UDP-glucuronyltransferase by differential centrifugation. Changes produced by pretreatment of rats with secretin, glucagon, vasoactive intestinal polypeptide and phenobarbitone.

Subcellular fractionation of liver homogenates from treated rats was carried out in order to study the mechanism of action of the gastrointestinal polypeptides on glucoronidation. Rats were treated for 90 min with an intravenous infusion of secretin (0.4 cU/h/100 g body weight), glucagon (100 micrograms/h/100 g body weight) and vasoactive intestinal polypeptide (VIP) (300 ng/h/100 g body weight); controls were sham-treated rats. For comparison, another group of animals was treated with a daily injection of phenobarbitone (10 mg/kg), a well-established enzyme inducer. Treatment with the different polypeptides produced minor changes in the subcellular localization of the enzyme. The bulk of activity was always recovered in the microsomal fraction, as identified by both differential centrifugation and the enrichment in specific activity of glucose-6-phosphatase, esterase and NADPH-cytochrome c reductase. Secretin produced a specific increase of bilirubin glucuronidation, more evident in all nuclear fractions. Glucagon increased both bilirubin and p-nitrophenol glucuronidation in all subcellular fractions. VIP had a selective action on p-nitrophenol conjugation of similar extent in nuclear and microsomal fractions. The type of changes observed is suggestive of physicochemical modifications occurring into the cell, perhaps at the membrane environment of different organelles, able to modify the overall conjugation of different substrates by the cell.

Animals↗
PubMed1987

[Glandulo-cystic polyps of the stomach. Apropos of 12 cases and review of the literature].

We report 12 cases of cystic glandular fundic polyps detected in 7 women and 5 men. As in the 238 similar previously reported cases these lesions were always located in the fundic gastric mucosae and did not involve the muscularis mucosae. They were discovered by endoscopy in patients with minor abdominal discomfort. They were less than 5 mm in diameter and were more often multiple and sessile; only a few of them were pedunculate. They consisted of mucosal cysts lined with cuboidal, parietal or chief cells and surrounded with a normal lamina propria. If in 213 cases, these polyps were not associated with polyposis coli in 37 cases they occurred with a Gardner's syndrome or a familial adenomatosis coli. These benign lesions are without malignant potential. Careful gastroscopic follow up with biopsy is recommended for all patients with multiple gastric polyps. The etio-pathogenesis of these polyps is still unknown. Their relationship to familial polyposis coli or to Gardner's syndrome is obscure.

Adenomatous Polyposis Coli↗
PubMed1979

[An incidence study of digestive cancers in a well defined population. Results of two years registration in the departement of Côte d'Or (author's transl)].

A systematic registration of mortality and morbidity from digestive cancers was started in January 1976 in the French department of COTE-D'Or (population 455,727). In the course of two years 913 new cases of digestive cancers were recorded. Nearly half of these cancers were colorectal cancers. The survey gives informations on histology, stage of the disease and survival. The morbidity survey allows comparison with the incidence rate of digestive cancers in other countries.

Adult↗
PubMed1979

Incidence of large bowel cancer in Côte-d'Or (Burgundy).

The present study is based on the registry of digestive cancers set up for the French department of Côte-d'Or (455,727 residents). Large bowel cancer represents half of the gastrointestinal tract cancers recorded in the course of 2 years (1976-1977). The crude annual incidence rate was 52.2 per 100,000 for males, 41.7 per 100,000 for females. The age-standardized incidence rate for cancer of the rectum is one of the highest reported. The incidence rates for cancer of the colon are in the intermediate range. Half of the large bowel cancers were rectal cancers, nearly always adenocarcinoma. Coexisting benign polyps were seen in 21% of the cases at the time of diagnosis of carcinoma and were more common in males than in females. 54% of cancers of the colon and 62% of cancers of the rectum underwent curative surgery.

Adenocarcinoma↗
PubMed1979

[Malignant lymphomas in Burgundy, France (1976--1977): a new approach using computerized pathological diagnoses (author's transl)].

Pathology laboratories in the Burgundy region have recently been equipped with mini-computers using the same software and working method. This report brings together their histological records, stored on magnetic discs, and describes the first results of this regional data base. Malignant lymphomas were chosen as a pilot study and evaluated between January 1976 and December 1977. After a brief presentation of the method, 246 cases of malignant lymphoma are analysed: 95 of Hodgkins disease, 103 of non-Hodgkins malignant lymphoma of the nodes and 48 cases of extranodal non-Hodgkins malignant lymphoma. The distribution of patients in terms of sex and ten year age groups is analysed, together with the various incidence rates for a year in Burgundy and in its four administrative units (Cote-d'Or, Nievre, Saone-et-Loire and Yonne).

Adolescent↗
PubMed1979

[Mucinous adenocarcinomas of the scalp. Anatomo-clinical, histochemical and ultrastructural study of a case and a review of the literature].

The third recurrence of a primary mucinous adenocarcinoma of the right parietal scalp was studied by histochemistry and electron microscopy. Histochemically the mucin produced by this neoplasm was of the sialomucine type. Electron microscopy revealed a high differentiated tumour whose cells looked like eccrine mucinous ones. The natural history of this carcinoma is similar to that of 33 ones already published. The tumours, round and elevated, grow in 75 p. 100 of the cases in patients over 50 years of age. They are located on the face or the scalp and more rarely on the trunk. Such tumours are frequently misdiagnosed as carcinomas. But the knowledge of thier morphological and histochemical features should lead to the right diagnosis all the more since the various biological and radiological investigations do not discover other primary neoplasm. Besides if these neoplasms are not metastases they are quite different from the other sweat gland carcinomas. They have a better prognosis than these tumours. However they give local recurrences, lymph node or subcutaneous metastases and a fatal issue in 6 p. 100 of the cases.

Adenocarcinoma↗
PubMed1978

A complete form of testicular feminisation syndrome; a light and electron microscopy study.

A case is described of testicular feminisation syndrome in a 19-yr-old patient with a normal female appearance. A laparotomy with removal of the gonads was performed. The latter looked like testes with intraparenchymal nodules. Light and electron microscopy study of these nodules revealed the presence of immature seminiferous-like tubules and of Leydig cell clusters. The tubules were filled with clear Sertoli cells, few degenerative dark cells and scanty spermatogonia. Thin collagen bundles surrounded the tubules and the foci of Leydig cells without any crystals of Reinke. The immaturity of all these cellular components could be connected with a mutation at a repressive locus which could be responsible for the abnormalities observed in the different steps of androgen action at target cell level.

Adult↗