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Biomedical subjects

A Lavergne

Publications and source records attributed to A Lavergne.

At least 55 records · Page 3Linked to original sources
PubMed1989

[Primary malignant melanoma of the esophagus arising in melanosis. Histological, immunohistochemical and ultrastructural study of a case].

The authors report a case of a primary melanoma of the esophagus, which is a rare neoplasm with poor prognosis. The diagnosis of malignant melanoma was suggested, on endoscopic biopsies, because of the presence of large malignant cells with abundant cytoplasm containing melanin pigment positive in the Fontana-Masson's reaction. These cells were immunoreactive for S100 protein while they did not show staining for antiepithelial membrane antigen and anti-keratin antibodies. Moreover ultrastructural study of the tumor cells revealed cytoplasmic aberrant premelanosomas. An important histological feature of the present case, which confirmed the primary oesophageal nature of the tumor was the presence of foci of melanosis (benign melanocytes) within the oesophageal epithelium which was adjacent to the melanoma. The variation in the histology of malignant melanoma may provide difficulties in diagnosis especially if one is limited to study a small biopsy specimen. In such cases other diagnoses including epidermoid carcinoma with prominent spindle-cell features and sarcomas should be eliminated by means of immunohistochemical and ultrastructural studies. The particular feature of our case, which apparently has not been reported previously, is the identification of the melanosis two years prior to the diagnosis of the malignant melanoma. The present study indicates that the identification of this lesion is of important diagnostic interest and might lead to the follow-up surveillance of the melanosis by multiple biopsies.

Esophageal Neoplasms↗
PubMed1988

Primary gastric peripheral T-cell malignant lymphoma with helper/inducer phenotype. First case report with a complete histological ultrastructural and immunochemical study.

Primary gastrointestinal T-cell malignant lymphomas (T-ML) are very rare. In this case report we describe a primary gastric tumor with local lymph node involvement. On the basis of histologic, immunohistochemical, and electron microscopic studies, the authors classified this tumor as a pleomorphic T-ML, large cell variant with peripheral helper/inducer T-cell phenotype (Leu1/CD5+, Leu4/CD3+, Leu5/CD2+, Leu9/CD7+, and Leu3/CD4+). The extreme pleomorphism of lymphoma cells, the numerous giant cells, and the presence of tumor nodules with two or three concentric layers were the three striking morphologic features of our case. Tumor cells showed an inconstant but true positive staining with anti-LeuM1/CD15 and LeuM3/CD14 antibodies. Vimentin positivity could be related to the presence of intermediate filaments at ultrastructural level. Neuron-specific enolase reactivity was a peculiar but unexplained feature. Furthermore, the positivity of the surface markers Ki-1/CD30, anti-Tac/CD25 and HLA-DR, and the nuclear marker Ki-67 suggested an activation state and a high proliferative activity of the tumor cells. This study emphasizes the usefulness of combined pathologic methods in order to rule other diagnoses such as undifferentiated carcinoma, malignant melanoma, malignant histiocytosis, B-cell lymphoma and interdigitating reticulum cells sarcoma, in view of an extremely polymorph tumor proliferation. This is apparently the first completely documented case report of a primary gastric pleomorphic T-ML of peripheral T-cell origin.

Antigens, Neoplasm↗
PubMed1988

Aortic 125I-albumin transport in patients with Marfan's syndrome and annuloaortic ectasia.

The morphologic, biochemical, and mechanical abnormalities of connective tissue fibrous proteins in Marfan's syndrome have been well studied, and their role in cardiovascular complications is well accepted. Less is known, however, about the state of the amorphous components of the aortic connective tissue. In the course of a study of transmural transport in blood vessels, we have had the opportunity to study dystrophic aorta from two young men who survived elective surgery; both with aortic insufficiency (AI) histologically compatible with Marfan's syndrome. One had recurrent chronic dissecting aneurysm (RCDA) as well. The aorta of the first (but not the second) was histologically compatible with Marfan's syndrome. Fresh specimens of intact ascending aorta were incubated in Krebs solution, pH 7.4, containing 125I-labelled bovine serum albumin for 2 h at 37 degrees C. The samples were then frozen, and serially sectioned in the plane of the lumenal surface. The radioactivity of the 20-micron thick sections was then determined, and expressed as a tissue/labelled solution concentration ratio. Transmural profiles of these ratios revealed no difference between the aorta of the RCDA patient with non-specific aortic dystrophy, and that of a 70-year-old man undergoing aortocoronary bypass. However, in the patient with aortic histology compatible with Marfan's syndrome, the average media concentration ratio was 5-fold less (4% vs. 20%).

Adult↗
PubMed1988

[Histiocytoid hemangioma of the heart. Histological and immunohistochemical study of a case].

We present the fourth case report of an histiocytoid hemangioma of the heart, which was found incidentally, as in the other three reported cases, in a 50 year old man during surgery for congenital heart disease. A polypoid sessile reddish tumor with a smooth surface, which measured 2 cm in diameter, was found in the right atrium. No necrosis nor cystic areas were seen. Histologic evaluation revealed a proliferation of histiocytoid or epithelioid cells, whose arrangement varied a great deal within the infiltrate. Sometimes, the cells were isolated but in most places they were arranged in sheets or nests surrounded by connective tissue. Some of these nests were compact whereas in others a lumen formation, frequently occupied by erythrocytes, could be appreciated. A striking feature was the presence of vacuolated tumor cells sometimes assuming a signet-ring configuration. Some large vascular spaces were lined by histiocytoid or epithelioid endothelial cells, many of which protruded into the lumen. Multinucleated tumor cells were occasionally observed. Mitoses were rare (up to 1/10 HPF) and scattered inflammatory cells such as lymphocytes, macrophages, neutrophils and eosinophils were seen. Histologic appearance of our patient's tumor is identical to the histiocytoid hemangioma of Rosai et al., which is an ubiquitous endothelial benign neoplasm.

Heart Neoplasms↗
PubMed1988

A primary immunoblastic T malignant lymphoma of the small bowel, with azurophilic intracytoplasmic granules. A histologic, immunologic, and electron microscopy study.

We report an aggressive primary T-immunoblastic lymphoma of the small intestine without blood involvement or associated celiac disease. Grossly, the tumor was composed of multiple disseminated ulcerated, infiltrating, or protuberant nodular lesions. Immunologic investigation showed that lymphoma cells were of peripheral (post-thymic) T-cell origin and expressed the phenotype associated with cytotoxic-suppressor subset (Leu4/CD3+, Leu9/CD7+, Leu2/CD8+, Leu11/CD16+, Leu 7/NKcells+, FcIgG+, HLA-DR+, anti-Tac/CD25+, Ki-1/CD30-, Leu1/CD5-, Leu5/CD2-, Leu3/CD4-). A particular morphologic feature of this case is the presence of numerous azurophilic granules within the lymphoma cells, identified as lysosomes by cytochemical and ultrastructural studies. In view of recent immunologic evidence that normal cytotoxic/suppressor T-cells selectively reside within the epithelium of the normal bowel and some of them contain azurophilic granules, it could be suggested that our patient's lymphoma represents a malignant counterpart of these lymphocytes. Furthermore, the aggressive character of this T malignant lymphoma (T-ML) could be related to the expression of T-cell activation markers HLA-DR and Tac/CD25 and the proliferation-associated antigen Ki-67 on a high proportion of tumor cells.

Cytoplasmic Granules↗
PubMed1987

Neuron-specific enolase and malignant lymphomas (23 cases).

The immunoreactivity of polyclonal antiserum to neuron-specific enolase (NSE) has been investigated. Twenty-three cases of malignant lymphoma (ML) were studied and compared with previously published reports. In our study 11 out of 23 cases showed strong or weak NSE positivity; any type of ML could be positive or negative even among B or T cell ML. This study indicated that polyclonal NSE is not a specific marker; it might be an inconstant marker of ML with no apparent correlation between reactivity and morphology or phenotype.

Antibodies, Monoclonal↗
PubMed1987

[Parathyroid microadenomas].

Ten out of 329 cases of hyperparathyroidism operated over a 4 year period had lesions which conformed to the diagnostic criteria of microadenoma. Although small and light weight these lesions all gave rise to complete laboratory work ups and 7 out of the 10 patients had clinical signs. The microadenomas were not easily identified at surgery and the diagnosis could only be confirmed after a thorough histological examination. After resection, all patients seemed to be permanently cured.

Adenoma↗
PubMed1986

Idiopathic chronic watery diarrhea from excluded rectosigmoid with goblet cell hyperplasia cured by restoration of large bowel continuity.

A 73-year-old woman developed abnormal electrolyte and water loss from an excluded rectosigmoid segment after surgical treatment of a volvulus of the sigmoid colon. Rectal discharges lasted almost for a year, until it spontaneously resolved after restoration of large bowel continuity. Despite extensive investigation, including endoscopic, radiologic, microscopic, bacteriologic and parasitic examinations, no satisfactory explanation of the diarrhea could be found. The histologic pattern of the excluded segment showed a striking increase in mucosal thickness and in number and height of goblet cells. These abnormalities disappeared after closure of the colostomy. Electrolyte composition of the rectal fluid, which contained 134 mmol potassium and 22 mmol sodium per liter was remarkable and similar to that of normal stool water and anal discharges of patients with ulcerative proctitis.

Aged↗
PubMed1986

Polydioxanone in digestive surgery. An experimental study.

An experimental study was carried out to analyze the reaction of polydioxanone suture. Two hundred ten single layer colonic anastomoses were performed in rats and histopathologically studied at nine different times between the 2nd and 180th postoperative days. Eighteen of 105 abdominal wound closures were studied in the same way between the 7th and 90th days. Polydioxanone was resorbed slowly in approximately 6 months with minimum inflammation. We believe that polydioxanone is actually the suture material of choice for all biliary and biliodigestive sutures.

Abdominal Muscles↗
PubMed1985

Limitations of fluorocarbons in reducing myocardial infarct size.

The effects of the oxygen-carrier fluorocarbons on myocardial infarct size were assessed in non-exchange-transfused dogs subjected either to a 3-hour occlusion of the left anterior descending coronary artery (LAD) followed by 2 hours of reperfusion (protocol I) or to a 5-hour permanent LAD occlusion (protocol II). Fluorocarbon administration was begun 30 minutes after LAD occlusion and was continued over the entire period of ischemia. After 5 hours, the hearts were excised and areas of necrosis were visualized by triphenyl tetrazolium chloride staining while risk regions were assessed by radiolabeled microspheres injected after coronary occlusion just before the onset of therapy, and further, in protocol I, by thallium-201 perfusion imaging performed at the end of fluorocarbon administration. In protocol I experiments, the ratio of necrotic area to area at risk was 81 +/- 35% (mean +/- standard deviation) in control saline-treated dogs (n = 6) and 67 +/- 27% in fluorocarbon-treated dogs (n = 6) (difference not significant). There was no significant difference between risk regions measured after and before fluorocarbon treatment. In protocol II, the ratio of necrotic area to area at risk was 47 +/- 30% in control dogs (n = 5) and 63 +/- 29% in fluorocarbon-treated dogs (n = 5) (difference not significant). However, in control dogs, the ratio of necrotic area to area at risk increased from 47 +/- 30% in the dogs that underwent permanent occlusion to 81 +/- 35% in the group that underwent reperfusion (p less than 0.001) while this ratio was similar in the corresponding subsets of fluorocarbon-treated animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗