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Biomedical subjects

M Pluot

Publications and source records attributed to M Pluot.

At least 19 recordsLinked to original sources
PubMed1991

Quantitative immunolocalization of four immunodominant antigens of Toxoplasma gondii.

Ultrastructural localization of four immunodominant antigens of Toxoplasma gondii was investigated quantitatively on thin sections and replicas by an immunogold technique using four monoclonal antibodies (Mab). On immunoblot Mab IV47, GII9, II38 and IE10 identified proteins of 28, 30, 45 and 66-70 kDa, respectively. Use of digital image analyzer and a semi-automatic procedure developed by us, the patterns of label distribution were compared in three cell structures: cell surface, submembrane area and rhoptries. On the whole cell surface, protein P28 and P30 were 2.5 and 4 times more abundant than P66-70 respectively. The protein P28 was essentially concentrated in the submembrane area with a labeling of 195.4 +/- 46.7 gold particles/microns 2 that follows a decreasing gradient from this area to the cell centre. In the rhoptries, all four antigens were detected, P45 and P66-70 being major with a labeling of 97.1 +/- 31.1 gold particles/microns 2 and 155.1 +/- 39.3 gold particles/microns 2 respectively. The results support the hypothesis that rhoptries are the essential site for antigen storage.

Animals↗
PubMed1991

[Invasive adenocarcinoma with epidermoid carcinoma on the site of bladder exstrophy. Histochemical and immunocytochemical study].

To date, one hundred and ten cases of malignant neoplasms arising from untreated bladder exstrophy have been reported. We describe another case of uncorrected bladder exstrophy with invasive adenocarcinoma and in situ squamous carcinoma discovered in a 51 year old woman. Postoperative radiotherapy was performed after cystectomy with nephroureterectomy and hysterectomy. The neoplastic samples were investigated by mucin histochemistry and immunocytochemistry. The epithelium lining the tumor villi and the surrounding mucosae was colonic with mucin histochemistry and reacted to anti KL1, EMA and ACE antibodies. These features were those of colonic and vesical adenocarcinomas. Although early vesical reconstruction is the best oncologic prevention, patients with bladder exstrophy run the risk of sigmoid adenocarcinoma after cystectomy and urinary diversion including ureterosigmoidostomy.

Adenocarcinoma↗
PubMed1991

[Acute malignant myelofibrosis. Report of 3 cases].

This report describes three cases of acute malignant myelofibrosis characterized by pancytopenia, absence of splenomegaly, bone marrow fibrosis with an immature cell proliferation and rapidly fatal outcome. The authors investigated the origin of blast cells with the use of immunohistochemical markers on paraffin embedded material with anti-factor VIII, BNH9 and anti-lysozyme. They studied the expression of megakaryoblastic, erythroblastic and myeloblastic differentiation in these cells. They demonstrated the heterogeneity of blast cells which are capable of differentiating along the three hematologic cell lines. The morphometric study showed the mutilating or systematized character of myelofibrosis. The increase in reticulin fiber density compared with normal bone marrow was not significantly different from two other types of myelofibrosis. It would be interesting to correlate a quantitative parameter with the course of this disease in order to evaluate the prognosis and the treatment.

Acute Disease↗
PubMed1991

[Value of the nucleolar organizers (AgNOR) in brain gliomas].

The aim of the study was to evaluate the feasibility and possible contribution of silver stained nucleolar organizer regions (AgNORs) to prognostic considerations, in a series of 55 supratentorial gliomas: eight grade II astrocytomas, twelve grade III astrocytomas, thirty grade IV astrocytomas, two glioblastomas, one anaplastic oligodendroglioma, one oligodendroglioma and one ependymoma. Silver NORs (AgNORs) were demonstrated according to the method of Crocker et al. A difference between AgNOR sizes in peritumor and tumor tissue is noted. The mean NOR numbers in the tumor areas range from 0.871 to 2.677, without overlap between peritumor gliosis and glial tumors. A comparative analysis reveals significant correlations between the mean NOR number per nucleus and histological grading. This technique can play a practical role in the diagnosis and grading of tumors sampled by stereotactic biopsies: a count higher than 0.8 is highly suggestive of malignancy. In addition, the distribution of NORs may be important: intratumoral heterogeneity expresses various degrees of transcriptional activity between different glial tumors of the same grade. This technique provides information about the biological behaviour of glial tumors supplementary to that obtained from growth fraction analysis.

Evaluation Studies as Topic↗
PubMed1990

Toxoplasma gondii: immunocytochemistry of four immunodominant antigens with monoclonal antibodies.

Four monoclonal antibodies in which diagnostic usefulness has been observed, concerning congenital, acquired, and reactivated toxoplasmosis, were raised against Toxoplasma gondii tachyzoïtes in order to localize immunodominant antigens. On immunoblots, it appears that McAb IV47, McAB GII9, McAb II38, and McAb IE10 identify families of proteins with estimated molecular weights of 28-30 kDa, 30 kDa, 45-50 kDa, and 66-70 kDa, respectively. By immunogold preembedding techniques one can observe an homogeneous labeling of the outer pellicle of the tachyzoïtes with the McAb GII9 and IV47 and a light labeling with the McAb II38 and IE10. The three-dimensional observation of cell surface antigens is performed by applying a modified metal extraction replica method, i.e., A plasma polymerization method of glow discharge by Tanaka (1979). By immunogold preembedding techniques [with saponin permeabilization (0.1%)], and by immunogold postembedding techniques, a labeling of the rhoptries is observed with McAb GII9 and McAb IV47 but essentially all label is found with McAb II38 and IE10. With McAb GII9 a uniform labeling is observed on the cell surface. By immunoenzymatic techniques (peroxidase) a cell surface labeling is observed with the four McAb. Intracellular Toxoplasma, the outer pellicle, and the vesicles of the network (elaborated by Toxoplasma in parasitophorous vacuole) are also labeled with McAb IE10. These results indicate that McAb GII9 recognizes antigens of the antigen family (P 30) located on the cell surface and in the rhoptries. The antigen recognized by McAb IV47 is essentially located on and beneath the Toxoplasma cell surface membrane, and McAb II38 and IE10 identify preferentially rhoptry proteins.

Animals↗
PubMed1990

Evaluation of morphological criteria in the cytological diagnosis of thyroid cold nodules. A preliminary study.

Although cytological diagnosis plays a significant role in the management of thyroid cold nodules, the rather high rates of false negative cases diminishes its usefulness. The purpose of this preliminary study is to evaluate the utility of numerous morphological criteria used by the cytologist to exclude benign tumours. Thirty-one cytological criteria were routinely scored as binary (yes/no) or as categories: 6 referred to the general arrangement and frequency of thyroid cells, 9 to the associated cellular and cell product elements, and 16 to the morphological features of the cells. We examined the manner in which these criteria, alone or combined, contributed to the diagnosis. The data base consisted of 171 intraoperative imprint cytological samples (143 histologically benign, 1 atypical adenoma and 27 cancers), as well as 257 thyroid cold nodule aspirates from another set of patients (198 histologically benign, 7 atypical adenomas and 52 cancers). For the imprint cytology, the diagnostic power of each criterion was individually assessed by the likelihood ratio (LR) which eliminated 11 as being undiscriminatory. The remaining independent criteria were subjected to logistic regression analysis to determine the most discriminant. Three were selected: Cellular clustering organisation, nuclear hypertrophy and colloid quantity with the latter being somewhat less powerful. Furthermore, it appears that the diagnostic power of the criteria was significantly lower when there was at least one nucleolus (number of nucleoli greater than 0). The smears gave essentially the same results as the imprints.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗
PubMed1990

[Contribution of monoclonal antibody HMB45 in the histopathologic diagnosis of melanoma].

We have tested the diagnostic value in malignant melanoma of HMB45, a monoclonal antibody available for use on paraffin-embedded tissue. MATERIAL AND METHOD. Tissues tested. The following pathological tissues were tested: 10 intradermal and 11 compound naevi; 6 spitz naevi; 20 dysplastic naevi; 10 blue naevi; 2 Bednar's tumours; 6 Sutton naevi; 15 melanonychias; 21 cutaneous and 11 ocular malignant melanomas (MM), and 3 achromic metastases. Control tissues were: vitiligo (20), carcinoma (5), malignant schwannoma of the orbit (1), soft tissue sarcoma (5) and malignant lymphoma (5). Antibodies. The antibodies used were antiprotein S100, antivimentin, anticytokeratin (KL1), monoclonal antileucocyte (CD45) antibodies and HMB45, a monoclonal antibody of the IgG 1 type obtained from lymph node metastases from pigmented malignant melanomas. RESULTS. None of the control tissues were stained by the HMB Ab. Intradermal naevi did not react positively. Compound naevi: the juntional cells were stained by HMB45 in 2/10 cases. Dysplastic naevi: HMB45 showed heterogeneous reactivity of junctional cells in 15/20 cases, and this correlated with the degree of atypia. Blue naevi: HMB45 stained the superficial and deep cells in 3/10 cases. Bednar's tumour: no cell was stained by HMB45. Spitz naevi: HMB45 gave an intensely positive reaction of junctional cells in 4/5 cases and a weaker reaction of dermal cells. Sutton naevi: the naevus cells were not stained by HMB45 in 5/6 cases. In simple melanocytic hyperplasia of the nail bed, only a few atypical cells were stained. In superficially spreading melanoma (SSM) all neoplastic cells were stained by HMB45 in proportion to their degree of atypia. Residual naevus cells were negative. The anti S100 and the antivimentin antibodies stained all neoplastic and naevus cells. In nodular melanoma (NM), HMB45 stained all neoplastic cells in proportion to their degree of atypia. The antivimentin Ab stained the neoplastic cells, and so did the anti-S100 Ab which also stained inflammatory cells. In acral-lentiginous melanoma (ALM), HMB stained the dermal tumoral cells moderately and the junctional cells more strongly. In ocular melanoma, HMB45 strongly stained the fusiform cells and less strongly the epithelioid cells. In achromic metastases from cutaneous malignant melanomas, HMB45 strongly stained the neoplastic cells but did not stain the peritumoral cells. DISCUSSION. The purpose of this study was to compare the value of HMB45 with that of other immunohistochemical staining methods A. Main data from the literature. (ABSTRACT TRUNCATED AT 400 WORDS)

Antibodies, Monoclonal↗
PubMed1990

[Malignant histiocytofibroma of the heart simulating myxoma of the left atrium].

The authors report a case of malignant fibrous histiocytoma of the left atrium which was excised but rapidly recurred in a 47-year-old woman. Clinical examination, echocardiography and the absence of biochemical abnormalities were in favour of the diagnosis of left atrial myxoma. This report illustrates the clinical similarity between myxoma and sarcoma of the left atrium. Very careful anatomopathological examination of multiple sections of the tumour are necessary to distinguish it from benign tumours, especially myxomas.

Diagnosis, Differential↗
PubMed1990

[Melanoma of the uvea in young patients. Apropos of 3 cases].

The authors report 3 cases of uveal melanoma, appeared on young women: 20, 23 and 28 years old. The melanomas were localized on the iris, the ciliary body and on the choroid. The authors studied the different notions of the literature about happened age of these lesions.

Adult↗
PubMed1990

[Cardiac metastasis secondary to digestive adenocarcinoma. A case report].

The authors report a case of cardiac metastasis revealing a malignant tumor of the biliopancreatic junction. This observation raises the problem of the diagnosis of revealing metastases. Immunohistochemical and ultrastructural studies may help to diagnose and identify primary tumors. This identification plays a major role predicting the prognosis and determining an optimal treatment.

Adenocarcinoma↗
PubMed1989

[Intramural pseudo-diverticulosis of the esophagus or cystic esophagitis? Study of an unusual surgical case].

The authors report an unusual case of oesophageal pseudo-diverticulosis. A 63-year-old male patient presented with dysphagia. A preoperative diagnosis of oesophageal intramural tumour was made on radiological and endoscopic abnormalities. The histopathological study of the involved oesophagus showed a pseudocystic dilatation of glandular ducts in the submucosa with a lymphocytic infiltrate. The authors review the relevant literature on oesophageal intramural pseudodiverticulosis and suggest a possible pathogenesis for this rare and benign entity.

Diverticulum, Esophageal↗
PubMed1989

[Synovial cysts and synovialomas of the lumbar spine. Histo-pathologic and neuro-surgical aspects apropos of 8 cases].

Based on 8 personal cases and a 81-cases review of literature, it's authors' opinion that cystic or solid masses issued form posterior lumbar articular process and called according to the cases synovial cyst, ganglion cyst, benign synovialoma, pigmented villonodular synovitis, are a single variety of benign degeneration of soft articular tissues. The cystic or solid feature of these masses depends upon the extent of their histiocytic granulomatous proliferation. They may be asymptomatic, accompany chronic lumbar pain or cause sciatica, seldom cauda equina syndrome. In case of sciatica, clinical picture rather consists of a narrow lateral recess than a discal protrusion. CT scan is the best investigation to get a right preoperative diagnosis. Postoperative prognosis is excellent and no anatomical recurrence has been reported.

Adult↗
PubMed1989

[Imprint cytology in the diagnosis of tumors of the thyroid].

We have correlated imprint cytology findings in thyroid tumors to the results of preoperative fine needle aspiration and operative specimen histology. Specificity of imprint cytology proved greater than that of fine needle aspiration cytology and topographic correlations were particularly helpful. Imprint cytology can improve the intraoperative histologic diagnosis. Because abundant cells are available, imprint thyroid cytology is ideal for teaching and training cytologists. Imprint cytology provides enough cells to perform special techniques, such as quantitative cytology, that are useful for the diagnosis of some tumor varieties (e.g. follicular tumors).

Cytodiagnosis↗