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Biomedical subjects

P Babin

Publications and source records attributed to P Babin.

At least 37 records · Page 2Linked to original sources

[Papillary fibroelastoma. A rare etiology of strokes in young patients].

BACKGROUND: The papillary fibroelastomas are cardiac lesions, which typically occur on the cardiac valves, but rarely on the endocardium. The incidence of these benign primitive tumors varies from 0.002 to 0.33% and increases with advancing age. METHODS: We report two cases of stroke, one in a 31-year-old man and the other in a 48-year-old woman, both admitted to the same stroke center. RESULTS: The diagnostic studies were normal in these two patients, except for the echocardiography. The first showed an echogenic mass on the mitral valve on transthoracic echocardiography (TTE), confirmed by the transesophageal echocardiography (TEE). The second demonstrated a mass on the sigmoid aortic valve on TEE, but the TTE was normal. For these two patients, a surgical excision was carried out and pathologic examination concluded to a papillary fibroelastoma. After surgery, no recurrence was observed. CONCLUSIONS: The papillary fibroelastomas are usually asymptomatic and easily detected by TEE. However, it can be revealed by stroke, myocardial infarction and lower limbs ischemia. These cardiac tumors should be surgically removed, since their complete excision remains the only means of avoiding a recurrence of embolism.

Adult↗

t(3;17)(q21;q25) in Epstein-Barr virus associated peripheral T-cell lymphoma: a paediatric case.

We describe an immunocompetent 8-year-old boy with a serological profile indicating chronic infection by Epstein-Barr virus (EBV) who developed subcutaneous and pulmonary lesions related to a peripheral T-cell proliferation. No clonal rearrangement of T-cell receptor or immunoglobulin genes was seen. However, the finding of a t(3;17)(q21;q25) in 44 metaphases from one skin lesion demonstrated a clonal origin. We also showed that the proliferative T cells contained EBV genome leading to the diagnosis of EBV-associated peripheral T-cell lymphoma. Further cytogenetic and molecular studies are needed to identify genes implicated in the pathogenesis of this haematological malignancy.

Child↗

Use of immunoblot assay to define serum antibody patterns associated with Helicobacter pylori infection and with H. pylori-related ulcers.

Serology has been used worldwide to detect Helicobacter pylori infection. Using an immunoblot assay with an antigen from strain ATCC 43579, we sought to determine the antibodies which were good markers of colonization and the antibody patterns associated with ulcers or atrophy. Out of 98 dyspeptic patients, 41 were colonized by H. pylori, based on a positive culture or on positive results of both a urease test and direct examination. These 41 patients were seropositive by an enzyme immunoassay, and 12 of them had ulcers and 29 had evidence of atrophy. Fifty-seven of the 98 patients were noncolonized. Twenty-five of the 57 had evidence of gastric atrophy, and 10 were seropositive; 5 of these 10 had ulcers. By Western blot analysis, 12 antibodies were significantly more frequent in sera from colonized patients, and they produced immunoreactive bands at 125, 87, 74, 66, 54, 48, 46, 42, 35, 30, 16 and 14 kDa. The presence of at least one band at 54, 35, or 42 kDa was the best marker of infection (sensitivity, 95%; specificity, 82%). In the group of colonized patients, none of the antibody patterns were correlated to gastric atrophy. Conversely, the presence of a band at 125, 87, or 35 kDa was statistically associated with the presence of an ulcer. The simultaneous presence of bands at 87 and 35 kDa predicted the risk of ulcers with 83% sensitivity and 69% specificity. By using CagA-positive and VacA-positive strains and CagA-negative and VacA-negative isogenic mutants, the antigens corresponding to the bands at 125 and 87 kDa were shown to be CagA and VacA, respectively. On the other hand, the 35-kDa antigen is a novel uncharacterized component of H. pylori. These results may help to optimize the composition of antigenic preparations for serologic detection of H. pylori colonization. Immunoblot assay would be useful for screening patients at high risk of ulcers.

Adolescent↗

Central nervous system relapses after autologous stem cell transplantation for myeloma. Report of two cases.

We report on two cases of central nervous system (CNS) relapse after high-dose chemotherapy and autologous stem cell transplantation. A 55-year-old man received two courses of vincristin, doxorubicin and dexamethasone (VAD) as an induction treatment for stage IIIB IgG kappa multiple myeloma. Bone marrow stem cell collection was performed after a high-dose melphalan (HDM) course (140 mg/m2). Autologous bone marrow transplantation (ABMT) was performed with this cryo-preserved unpurged bone marrow sample after a second HDM course. Three months after ABMT, the patient presented with signs of central nervous involvement with plasma cells and monoclonal IgG kappa in the cerebral fluid. The patient died despite systemic and intrathecal chemotherapy. A 50-year-old man was initially treated with 3 courses of VAD for a stage IIIA IgD lambda multiple myeloma. Blood stem cell were collected after a course of high-dose etoposide and cyclophosphamide. ABMT was performed after total body irradiation (TBI) and HDM. Three months later, he presented with right leg palsy and a lumbar puncture showed numerous plasma cells and the presence of the IgG lambda. The patient died of neurological complications three months later. Extramedullary occurred prior to medullary relapse in the two cases, suggesting the presence of an extramedullary clone of plasma cells with a high degree of chemo-resistance. Although high-dose chemotherapy appears promising, this therapeutic approach could allow the occurrence of presently unobserved complications. Wether CNS prophylaxis is indicated in this context, as recommended in leukemia, remains an open question.

Central Nervous System Diseases↗

Allogeneic bone marrow transplantation for hypereosinophilic syndrome with advanced myelofibrosis.

A 33-year-old man with an atypical course of hypereosinophilic syndrome including malignant hypercalcemia, osteolytic lesions and evolution into severe myelofibrosis was treated by allogeneic bone marrow transplantation after conditioning with cytoxan and total body irradiation. As the transplant was sex-mismatched, chimerism was studied by means of cytogenetic analysis and Y chromosomal DNA amplification by PCR assay. Long-term complete remission has been assessed by normalization of blood cell counts, magnetic resonance imaging and karyotypic analysis. A relapse was observed 40 months after transplantation. The patient remains alive 44 months post-BMT. This case report is compared with those reported in the literature.

Adult↗

[Reoperations of total hip prosthesis with acetabular reconstruction using bone allografts].

Detachment of the acetabular segment is the most important long-term problem with total hip prostheses. We analyzed long-term outcome in our first 48 acetabular reconstructions with cryopreserved allografts. Among the 48 hips operated on with this technique, 38 were reassessed after a mean follow-up of 7 years 3 months (range 5 years-9 years 6 months). Mean age of the population at surgery was 63 years. There were two predominant etiologies: sequelae of chronic hip luxation and primary osteoarthrosis of the hip. In 10 cases with massive destruction, the Müller ring was used to stabilize the allograft. Results were assessed at 6 months, 2 years, 4 years and at longest follow-up using the Merle d'Aubigné clinical assessment scale. For the radiographic assessment, the Ranawat criteria were used to evaluate the alignment of the reconstruction. Clinically, patient comfort was improved in all cases with significant pain relief. Radiologically, mean acetabular ascention was 5 mm and mean medialization was 3.5 mm. A rim was observed in 24 cases including 19 measuring less than 2 cm. Acetabular loosening was evidenced in the 5 other cases where the rim measured more than 2 mm. In 4 of these 5 cases, the acetabulum had migrated to a new setting. The radiographic image then remained unchanged. Analysis of our 38 first cases showed that bone allografts with cimented acetabulum, sometimes with a stabilizing ring, is one of the possible solutions for difficult acetabular reconstructions. However, after a 7 years 3 months follow-up, we have had five (13%) aseptic displacements including one case requiring reoperation. In the 33 stable joints (87%) with good results reconstruction has achieved a nearly perfect anatomic position, similar to first intention arthroplasty with the use of perfectly stabilized bone grafts with a maximal acetabular surface. Our follow-up is longer than most published in the literature. However, the migration rate of 13% it is still too short to draw any conclusion concerning the long-term outcome in our patients, despite their older age and reduced physical activity compared with primary hip arthroplasty patients.

Adult↗

[Pathological anatomy of primary cerebral lymphoma].

In this retrospective study (1986-1996), a series of 250 immunocompetent patients (SFNC series) with primary malignant lymphoma of the central nervous system is reviewed and the lymphomas redefined using the REAL (Revised European-American classification of Lymphoid neoplasms) and the modified Kiel classifications. All the tumors available for review were classic diffuse non-Hodgkin's lymphomas. Thirty-eight were unclassifiable due to small size and artifacts in the specimens. Eight cases were of T-cell type (3.7%). The 212 others cases were B-cell type. According to the REAL classification, the high majority was diffuse large cell (62%). Following the modified Kiel classification percentage of cases categorized as low and high grade of malignancy were 22.4% and 77.6% respectively.

Brain Neoplasms↗

Changes in Helicobacter pylori ultrastructure and antigens during conversion from the bacillary to the coccoid form.

In vitro, Helicobacter pylori converts from a bacillary to a full coccoid form via an intermediate U-shaped form. Organisms with a full coccoid form keep a double membrane system, a polar membrane, and invagination structures. Western blots (immunoblots) of sera from colonized patients show that some high-molecular-mass antigenic fractions are expressed only in coccoids. Conversely, fractions of 30 and 94 kDa were more intensively detected in the bacillary forms. These results suggest that (i) coccoid conversion is not a degenerative transformation and (ii) antigens specific to the coccoid forms are expressed in vivo.

Antigens, Bacterial↗

Evidence of chromosomal instability in the lymphocytes of Gorlin basal-cell carcinoma patients.

The Gorlin syndrome, or naevoid basal-cell carcinoma syndrome (NBCS) is an autosomal dominant disease. It has been suspected for long that this cancer prone disease (multiple basal-cell carcinomas; other malignant or benign proliferations) is a chromosome instability syndrome. We previously reported a lengthening in the cell cycle of lymphocytes from two patients with NBCS. With a larger sample (n = 7), we confirm this disease to be a chromosome instability syndrome, although clearly, expression of this characteristic can vary between patients: (1) spontaneous chromatid breaks occurred more often in a subset of the patients; (2) spontaneous micronuclei were found more frequently in NBCS than in the controls; (3) we confirm the cell cycle to be affected in this disease. As these results were obtained on lymphocytes--a cell lineage not affected in NBCS manifestations--the chromosome instability we found would appear to be part of the general condition of this syndrome.

Adult↗

Cell-mediated cytotoxicity can be regulated by p53 tumor suppressor gene activity in vitro.

The wild-type human p53 tumor suppressor gene was tested for its ability to modulate cytotoxic activity of in vitro activated peripheral blood lymphocytes. Peripheral blood mononuclear cells (PBMCs) were stimulated by phytohemagglutinin (PHA), interferon alpha 2b (IFN alpha 2b), interleukin 2 (IL-2) or their combinations to induce cytotoxicity. This stimulation significantly increased the percentage of cells expressing p53, which was at its maximum when induced by IL-2 combined with IFN alpha 2b. The role of p53 in the modulation of different aspects of cytotoxic activity of these cells was analyzed by studying the effects of p53 abrogation by antisense oligonucleotide (p53 AS) treatment in comparison with p53 sense or scrambled (missense) oligonucleotide (p53 S or p53 MS) treatment. We show that p53 plays a key role through induction of apoptosis in target cells (tumor necrosis factor pathway) rather than through osmolytic degeneration (perforin pathway) which is only slightly increased by p53 abrogation. Meanwhile, in vitro abrogation of p53 expression in PBL was found to be accompanied by an increase of CD8+ lymphocytes and an important increase of the CD56 'bright' NK cell sub-population.

Antigens, CD↗

Cathepsin D in normal and neoplastic thyroid tissues.

BACKGROUND: Cathepsin D is a widely distributed lysosomal acidic endopeptidase. It is an estrogen-regulated protein that is a prognostic factor in breast cancer. The aim of this study was to measure cathepsin D concentrations in thyroid tissues and to correlate these concentrations with clinical and pathologic parameters. METHODS: Cathepsin D and thyroglobulin concentrations were measured in the cytosol of normal thyroid tissues (n = 14), benign nodules (n = 6), and thyroid carcinomas (n = 32) with an immunoradiometric assay. Statistical analysis was based on the Kruskal-Wallis and Wilcoxon tests and on the Spearman rank correlation coefficient. RESULTS: The mean level of cathepsin D, expressed as picomoles per milligram protein minus thyroglobulin, was higher in the 32 carcinomas, 29.1 +/- 15.5, than in the 14 normal thyroid tissues, 8.4 +/- 2.5 (p < 0.001) or in the 6 benign nodules, 11.2 +/- 7.3 (p = 0.003). Cathepsin D concentrations correlated with tumor size; Spearman rank correlation coefficient was rs = 0.44 (p = 0.012). No significant difference was found regarding histologic type. Cathepsin D concentrations were inversely correlated with the thyroglobulin level in the tumor; Spearman rank correlation coefficient was rs = -0.60 (p < 0.001). CONCLUSIONS: Cathepsin D concentration is higher in thyroid carcinoma than in normal thyroid tissue. Increased cathepsin D concentrations correlate with thyroid tumor size but not with histologic type. Further studies should be done to confirm the potential prognostic value of cathepsin D in patients with thyroid carcinomas.

Adult↗

[Demonstration of molecular forms of Rap 1 in cells or tissues deriving from normal or pathological human colonic epithelium].

Mutations of the cK-ras gene which confer oncogenic properties to the corresponding encoded small G protein, occur in 30 to 50% of the human colonic adenocarcinomas. Overexpression of Rap 1A, a member of the Ras family, in K-ras transformed fibroblasts, reverts the transforming properties of the oncogene. This indicates that Rap 1A may exert antagonistic properties towards the K-Ras protein. In this respect, we have been interested in comparing Rap 1 expression in the human adenocarcinoma cell line HT29 and in safe or pathological tissues deriving from the human colonic epithelium. In the human adenocarcinoma cells HT29, several immunoreactive forms of Rap 1 of 71 kDa, 47 kDa, 40 kDa and 24 kDa are detected. Extraction in Triton X-114 allows separation of HT29 cell proteins on the basis of their differential hydrophobic properties. Parallelly, proteins were separated in crude cytosolic or membrane fractions. Most of the immunoreactive material corresponding to the 24 kDa band may contain hydrophobic and membrane associated components. The molecular nature of the higher size components is also discussed here. In the tissues, the 47 kDa form which is common in all of the safe and pathological samples considered, appears to be specifically expressed in the colon. Besides, the 71, 68 and 24 kDa were found in pathological tissues. High expression of Rap 1 was demonstrated to be correlated with cell differentiation in the safe colonic epithelium and in the adenomas. Cloning of the Rap 1A cDNA is now in progress in the laboratory, using PCR detection in an HT29 expression library.

Adenocarcinoma↗

Strategy for identifying primary malignancies with inaugural bone metastases.

The diagnosis of primary tumors with inaugural bone metastases is a serious and difficult problem commonly encountered in rheumatology. Helpful information can be derived from the radiologic appearance of the metastases, history of the patient, clinical findings, chest film, standard laboratory tests, imaging studies, serum marker assays, and histologic findings. Based on our personal experience and on previously published data, we have developed a decision tree aimed at enhancing the efficacy of the diagnostic process while ensuring optimal patient comfort and containing costs.

Adult↗

Checks for chromosomal instability in Gorlin and non-Gorlin basal-cell carcinoma patients.

The naevoid basal-cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder with multiple basal-cell carcinomas, an increased risk for other neoplasms, and various malformations. Chromosome instability has been implicated in the pathogenesis of this syndrome, but these reports are somewhat contradictory. We have investigated five patients, two with confirmed NBCCS and three suspected. No evidence for chromosome instability was found in lymphocytes at three sample times after stimulation using metaphase aberration analysis, sister-chromatid exchange (SCE) in second division cells, or micronuclei. A significant lengthening of the cell cycle was found for the two confirmed NBCCS patients, but not for the suspected cases.

Adolescent↗