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J P Saint-Andre

Publications and source records attributed to J P Saint-Andre.

At least 19 recordsLinked to original sources
PubMed2000

High-field quantitative transverse relaxation time, magnetization transfer and apparent water diffusion in experimental rat brain tumour.

The potential of quantitative parameter images of transverse relaxation time T(2), apparent diffusion coefficient (ADC) and magnetization transfer ratio (MTR) to characterize experimental brain tumours was studied. Necrosis or haemorrhage can be detected using either MTR, ADC or T(2) (necrosis-MTR reduced by 35%, ADC and T(2) increased respectively by 170% and 100% compared with normal brain tissue; haemorrhage-MTR increased by 60%, ADC and T(2) decreased by 40% and 20%, respectively). Normal brain tissue can only be distinguished from tumour on T(2) and MTR parameter images. However, for small tumours (10 microl), the best contrast is observed with MTR, ca. 30%, whereas for T(2) the contrast is ca. 10%.

Animals↗
PubMed1999

Medullary thyroid microcarcinoma: a clinicopathologic retrospective study of 38 patients with no prior familial disease.

Thirty-eight patients (25 women, 13 men; mean age, 57.8 [32 to 91]) showing one or more medullary thyroid microcarcinomas (ie, < 1 cm), with no prior MEN II or medullary thyroid carcinoma history in their family, were reviewed. Follow-up was available for 29 patients (mean, 53.6 months [1 to 147]). 21 patients (72.4%) are alive and free of disease, four patients (13.8%) died during follow-up without disease, 2 patients are alive with disease (local recurrence and persistent hypercalcitoninemia) after 80 and 99 months, respectively, and 2 patients died of disease after 24 and 46 months. Most tumors were incidental pathological findings (19 of 38) or were discovered by systematic blood calcitonin measurement for a nodular thyroid disease (15 of 38). Only the four patients who had an unfavorable outcome were symptomatic cases (palpable micro-MTC, diarrhea, cervical lymph node metastasis and pulmonary metastatic disease). The two patients with metastatic disease at diagnosis died during follow-up. In univariate analysis, a symptomatic medullary thyroid carcinoma was a strong predictor of an unfavourable outcome (p < .00008), as were the preoperative calcitonin level (P = .007) and an elevated postoperative calcitonin level (P = .004). Among 30 histopathological criteria, only the presence of amyloid correlated with an unfavorable outcome (P = .018).

Adult↗
PubMed1996

Immunohistochemical study of 100 pancreatic tumors in 28 patients with multiple endocrine neoplasia, type I.

One hundred pancreatic tumors ranging in size from 0.3 to 7 cm were studied in 28 patients (17 male and 11 female patients; mean age 35 years) with multiple endocrine neoplasia, type I. An immunohistochemical study was performed on deparaffinized sections using the following antibodies: neuron-specific enolase, chromogranin A or synaptophysin, insulin, glucagon, somatostatin, pancreatic polypeptide (PP), vasoactive intestinal peptide (VIP), gastrin, adrenocorticotropic hormone, alpha-subunit of human chorionic gonadotropin, gonadotropin-releasing factor, serotonin, and calcitonin. Among the 100 tumors (all multiple), seven were unclassified, 10 were plurihormonal, and 83 produced a predominant hormonal secretion (with 50-90% of the same cell type), including 37 "A-cell tumors" (glucagon), 27 "B-cell tumors" (insulin), 11 PP-cell tumors, one G-cell tumor (gastrin) and one vasoactive intestinal peptide (VIP)-cell tumor. These multiple tumors had a different predominant hormonal secretion in the same patient in 23 of the 28 cases. There was a preferential association of A-cell tumor and B-cell tumor. Hyperplasia of the islets of Langerhans was not detected in adjacent pancreas. Nesidioblastosis was observed in 30% of cases.

Adolescent↗
PubMed1994

C-cell hyperplasia associated with chronic lymphocytic thyroiditis: a retrospective quantitative study of 112 cases.

Since the first description by Wolfe et al of C-cell hyperplasia (CCH) in asymptomatic relatives of patients suffering from a medullary thyroid carcinoma (MTC), several investigators have described CCH associated with a chronic lymphocytic thyroiditis (CLT) not within the context of MTC or multiple endocrine neoplasia (MEN). We report the study of C-cell density in 112 cases of CLT on retrospective surgical material to determine the frequency of the association between CCH and CLT. The cases of CLT were compared with 19 normal thyroid glands obtained at necropsy. C cells, immunoreactive with a polyclonal anti-calcitonin (CT) antibody, were counted at high magnification (X400) and the number of low-power magnification (X100) microscopic fields (LPFs) containing at least 50 C cells per slide was assessed. Image analysis was performed to determine the C-cell density expressed in number of C cells/cm2. C-cell hyperplasia was defined by the following criteria: C-cell density > 40 cells/cm2 and the presence of at least three LPFs containing more than 50 C cells. Twenty percent of the cases of CLT showed a CCH thus defined, and four of them had an elevated serum CT level. Statistical analysis showed no clinical or biological correlation with the presence of CCH. However, the frequency of CCH was higher if a follicular cell carcinoma was associated with CLT. This study confirms a pathological association between CCH and CLT, provides new criteria for the definition of CCH on surgical pathology material, and reports four cases with an elevated serum CT level not within the context of MTC or MEN.

Adolescent↗
PubMed1993

Translocation t(11;19) (q23;p13) in a child with myelomonocytic leukemia following 2 years after chemotherapy for pneumoblastoma.

A child, who received successful chemotherapy for pneumoblastoma, developed a myelomonocytic leukemia with translocation t(11;19)(q23;p13) 2 years later. Although this leukemia did not present with features generally associated with therapy-related leukemias, we think this hematologic disease to be secondary to previous chemotherapy. Involvement of chromosome 11q23 is common in acute leukemia and seems to be more significantly related to ANLL in young children (M4 and M5 FAB classification). However, our observation and previous reports suggest that this chromosomal abnormality might be more frequent in therapy-related leukemias. The responsibility of etoposide and cisplatin may be discussed in such secondary malignancies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1992

Contribution of immunohistochemistry, electron microscopy, and cell culture to the characterization of nonfunctioning pituitary adenomas: a study of 40 cases.

We studied 40 endocrinologically inactive pituitary adenomas by immunohistochemistry, electron microscopy, and cell culture in order to determine the incidence of gonadotropic adenomas and to classify nonfunctioning adenomas. Immunohistochemical studies using a large panel of monoclonal and polyclonal antibodies identified the following nonfunctioning adenomas: 20 gonadotropic adenomas, four silent corticotropic adenomas, one plurihormonal adenoma, and 15 nonsecreting adenomas. Among nonsecreting adenomas, ultrastructural study of 13 cases identified seven null cell adenomas and six oncocytomas. Silent corticotropic adenomas were classified into subtypes I, II, and III according to Kovacs and Horvath. Most often, gonadotropic adenomas displayed a varying number of oncocytic cells, characteristic secretory granules, and a prominent Golgi apparatus. Postembedding immunoelectron microscopy was performed on eight gonadotropic or nonsecreting adenomas, but this technique did not provide any additional information. Six gonadotropic adenomas and 10 so-called nonsecreting adenomas were studied in primary cell cultures. The six gonadotropic adenomas and seven of the 10 nonsecreting adenomas released gonadotropins in the culture medium. The use of in vitro results as a supplementary diagnostic criterion allowed classification of the 40 nonfunctioning adenomas as follows: 27 gonadotropic adenomas, four silent corticotropic adenomas, one plurihormonal adenoma, and eight nonsecreting adenomas. These results demonstrate a high proportion of gonadotropic adenomas among nonfunctioning adenomas (67.5%) and the usefulness of several techniques in characterizing this type of pituitary adenoma.

Adenoma↗
PubMed1991

Presence of renin, angiotensinogen, angiotensin II in the lamb anterior pituitary gland: immunocytochemical study after cryoultramicrotomy.

The presence of renin, angiotensin I-converting enzyme and angiotensin II detected by immunocytochemistry in the adult male rat anterior pituitary has suggested the existence of a pituitary renin-angiotensin system. To establish another mammalian experimental model we have investigated the presence of renin, angiotensinogen, angiotensin I-converting enzyme, and angiotensin II II in five normal lamb anterior pituitaries by immunocytochemistry after cryoultramicrotomy. Renin, angiotensinogen and angiotensin II immunoreactivities were observed only in cytoplasmic granules of lactotrophs, and the three proteins were found co-localized with prolactin in the same granules by double immunolabelling. No immunoreactive angiotensin I-converting enzyme was observed. These results suggest an activation of renin in the cytoplasmic granules of lactotrophs leading to a local synthesis of angiotensin II. Thus, the lamb anterior pituitary may provide a good experimental model for investigating the possible autocrine action of a local renin-angiotensin system on prolactin release in the human pituitary.

Angiotensin II↗
PubMed1990

Stenotic intimal thickening of the external iliac artery in competition cyclists.

Twenty-three cases of an arterial disease that affects competition cyclists are reported. Patients complained of intermittent acute claudication appearing on one lower limb only at the time of a maximal strain while cycling. Doppler hemodynamic investigation on an ergometric bicycle revealed a collapse of the ankle systolic pressure. Arteriography showed a sinuous lengthening and moderate stenosis of the external iliac artery. Pathologic examination of the artery disclosed a stenotic intimal thickening due to moderately cellular loose connective tissue with a variable distribution of collagen and elastic fibers. The cells in the affected zone were readily labeled with anti-actin and anti-myosin antibodies, and electron microscopy revealed features of synthetic smooth muscle cells. The lesion observed differs from intimal fibrodysplasia and from artherosclerosis. Abnormal local hemodynamic conditions may lead to this type of lesion. Thus, stenotic intimal thickening of the external iliac artery appears to be a new arterial disease defined by clinical, arteriographic, and pathologic features.

Adult↗
PubMed1990

Immunocytochemical and biochemical evidence of renin in human lactotrophic cell cultures.

Primary cell cultures from human prolactin (PRL)-secreting adenomas were used to test the ability of human lactotrophs to synthesize renin in vitro. The renin content of the culture medium and of cellular extracts was measured by enzyme-linked immunosorbent assay. The level of PRL release in the culture medium and the amount of PRL in a cellular extract were determined by radioimmunoassay. Morphologic studies included indirect immunofluorescence, pre-embedding immunoelectron microscopy using a three-layer peroxidase-antiperoxidase method and postembedding immunoelectron microscopy using protein A-gold complexes. Renin was detected in cellular extracts and was found to be absent in the culture medium, whereas PRL was extracellularly secreted. PRL and renin immunoreactivity was observed in all the cultures studied by immunofluorescence. The subcellular localization of renin was found to be similar to that of PRL and was observed in the rough endoplasmic reticulum, the Golgi apparatus, and cytoplasmic secretory granules. The results suggest that, in vitro, renin may be synthesized and intracellularly metabolized in human adenomatous lactotrophic cells rather than secreted. Cell cultures may be a useful model to further the understanding of the role of a local renin-angiotensin system in PRL secretion.

Female↗
PubMed1990

Transient acanthosis nigricans following bone marrow transplantation for lymphoid malignancy.

Transient acanthosis nigricans (AN) was observed 3 months after bone marrow transplantation (BMT) for lymphoblastic lymphoma. The patient had no endocrine abnormality and had not received any drug known to induce AN. Forty-eight months post-BMT no malignancy recurred or appeared. Although usual hyperkeratosis, papillomatosis and acanthosis were present on skin biopsy, these were associated with the finding of keratinocyte necrosis and CD8+ lymphocytic infiltrate. It is suggested that graft-versus-host disease may be one of the triggers for AN.

Acanthosis Nigricans↗
PubMed1989

Four brothers with Waldenstrom's macroglobulinemia.

An exceptional family including four brothers with Waldenstrom's macroglobulinemia was studied. The four patients had different light chain IgM monoclonal components: two of the kappa type and two of the lambda type. Anti-idiotypic rabbit antisera, prepared for each monoclonal component, revealed no cross-reactivity. The four brothers did not share a common HLA A B DR haplotype and a genetic linkage to the HLA complex cannot be ascertained. Five of the 12 relatives had high serum immunoglobulin concentration (four IgG, three IgA, and two IgM) without monoclonal components. Two relatives showed auto-antibodies at low titer. Some of the youngest relatives exhibited immunological abnormalities and they may be high-risk subjects with regard to Waldenstrom's macroglobulinemia.

Aged↗
PubMed1989

A case of temporal arteritis with intrahepatic arterial involvement.

We report a case of temporal arteritis associated with anicteric cholestasis. Serial sections of a transthoracic needle biopsy of the liver revealed giant-cell arteritis in medium-sized hepatic arteries and cholangitis in adjacent bile ducts. The literature reveals that similar pathologic features have only exceptionally been observed in liver biopsies. These lesions may account for liver function disturbances commonly seen in temporal arteritis or polymyalgia rheumatica.

Aged↗
PubMed1988

Angiotensin-I-converting enzyme in germinomas.

Angiotensin-I-converting enzyme (ACE) was detected in 18 germinomas, both of testicular or extratesticular localization, and studied by immunohistochemical methods using specific polyclonal antibodies and by enzyme activity measurements. ACE was also detected in normal human germ cells. On the other hand, it was not present in other types of testicular tumors. Biochemical studies and immunohistochemical findings suggest that at least part of the enzyme is membrane bound. Plasma ACE levels appeared to be normal, indicating that measurement of plasma ACE levels in germinomas would be of little help for the diagnosis and follow-up of patients. However, the apparent specificity of ACE detection in germinomas among germ cell tumors might help in histologic diagnosis, especially for tumors of extragonadal localization.

Dysgerminoma↗
PubMed1987

Sarcomatous degeneration in Paget's bone disease.

The authors report 12 cases (8 men and 4 women) of sarcomatous degeneration in Paget's bone disease, with an average age of 72.3 years. Sarcomatous degeneration occurred often in polyostotic Paget's disease, and osteitis deformans was seen in 4 cases. Femur and pelvis were the most affected bones. Pain was a constant feature, whereas tumefaction and fracture were less common. Osteolytic lesions were more frequent than condensed or mixed lesions and radiological signs of malignancy were usually found. Seven cases were histologically classified as osteogenic sarcoma and 3 cases as fibrosarcoma. Electron microscopy was performed on 2 osteogenic sarcomas and in 1 case revealed microcylindrical inclusions in Pagetic osteoclasts and in multinucleated giant tumor cells, but none in mononucleated tumor cells. The average survival time for the patients in this study was only 4.5 months.

Aged↗
PubMed1987

Angiotensin I-converting enzyme in a suprasellar germinoma.

High levels of angiotensin I-converting enzyme (ACE) were found by both direct radioimmunoassay and enzyme activity evaluation in a patient's plasma that had suprasellar germinoma. ACE levels returned to normal values after surgery, suggesting the tumor was the cause of the elevated plasma ACE. ACE was found in the tumor, and ACE activity was measured in a tumor extract. With the use of specific antihuman ACE antibodies, ACE was localized by immunohistochemistry in the tumoral germinal cells. Because ACE was also found in testicular germinomas, it appears to be a possible marker for germ cell tumors.

Aged↗