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R Bouvier

Publications and source records attributed to R Bouvier.

At least 91 records · Page 5Linked to original sources

Regional distribution of substance P binding sites in the brainstem of the human newborn.

The distribution of [3H]substance P ([3H]SP) binding sites in the brainstem of the human newborn was investigated in eleven cases (aged 1 h to 6 months) by in vitro quantitative receptor autoradiography. The binding of [3H]SP to newborn brainstem tissue was found to be saturable (for the eight cases examined, Kd and Bmax (M +/- S.E.M.) were 0.29 +/- 0.03 nM and 206 +/- 21 fmol/mg tissue, respectively). Competition studies showed unlabeled SP to be the most potent peptide for displacing [3H]SP binding from tissue sections. The desaturating effect of GTP on the specific binding of [3H]SP was also investigated, but was not found to be significant. Autoradiographic analysis showed that the neurokinin-1 (NK-1)/SP binding sites were widely but unevenly distributed, and that they varied with age. The highest densities of (NK-1)/SP binding sites were observed in the locus coeruleus, olivaris inferior nuclei, raphe magnus and obscurus nuclei, while low to moderate densities were observed in other brainstem structures. These findings support the idea that SP is involved in cardiovascular regulation, and that it may interact with the catecholaminergic and/or serotonergic system.

Autoradiography↗

Complications of percutaneous liver biopsy in infants and children.

UNLABELLED: In this study, 144 consecutive percutaneous liver biopsies performed with a 1.6 mm Menghini needle, during a 2-year period were reviewed. All the children were aged under 15 years, 57 patients less than 1 year and 87 more than 1 year. All biopsies were adequate and the mean number of portal tracts examined was 17.6 per biopsy (14.3 in patients weighing less than 10 kg and 19.1 in the others). There were no deaths and we observed only bleeding complications. In patients with normal coagulation (128 cases), 1 bleeding requiring transfusion occurred; and in patients with abnormal coagulation (16 cases), we observed 2 bleeding cases requiring transfusion. CONCLUSION: Percutaneous liver biopsy can be performed with 1.6 mm needles in children. For increased safety, ultrasound-guided biopsies are recommended.

Adolescent↗

[Primary AL-type amyloidosis disclosed by Horton disease].

Primary systemic amyloidosis rarely affects the walls of small and medium-sized vessels. We report a case of primary AL amyloidosis masquerading as giant cell arteritis at the onset of the disease, revealed by the temporal arteritis biopsy, and successfully treated by corticotherapy for three years. Histology of temporal arteritis confirms the diagnosis of amyloidosis (characteristic birefringence with Congo red). We discuss in this case the diagnosis of primary amyloidosis revealed by Horton disease, or the coincidental association of these two diseases.

Aged↗

[Early manifestations of Tangier disease].

BACKGROUND: The diagnosis of Tangier disease in childhood is based on the specific aspect of tonsils or by screening relatives of affected subjects. CASE REPORT: A moderately enlarged liver associated with splenomegaly was found upon routine physical examination of a 3 month-old breast-fed boy, born in Turkey from consanguineous parents. Laboratory studies disclosed moderate increase in serum alanine aminotransferase activity (ALAT 52 UI/l, N < 30). The diagnosis of Tangier disease was confirmed by studies of plasma cholesterol and apolipoprotein A. By 8 months of age, the patient had enlarged orange tonsils. Small cervical, axillary and inguinal lymphadenopathies were present. The tonsilar and adenoidal tissues were removed at 18 months of age because the patient suffered from chronic airway obstruction. Colonoscopic examination revealed tiny flat orange spots, 1 to 2 mm in diameter, scattered throughout the rectosigmoidal and colonic mucosa. Survey of the family led to the discovery of one sister, with asymptomatic apolipoprotein Al deficiency and a normal sister, while the parents were heterozygotes for Tangier disease. CONCLUSION: Enlarged liver associated with a moderate level in serum aminotransferase may be an early manifestation of Tangier disease in infants. Rectosigmoidal and colonic lesions may be convenient for biopsy when tonsillectomy is not indicated.

Hepatomegaly↗

Evaluation of CD44 prognostic value in neuroblastoma: comparison with the other prognostic factors.

CD44 gene products are potential markers of aggressiveness in different tumour models, a result which prompted us to study clinical neuroblastoma (NB) specimens. CD44 expression was determined by immunostaining of 52 tumour samples from newly diagnosed NB with a monoclonal antibody (J173) directed against an epitope common to all CD44 isoforms. CD44 immunoreactivity was detected in 37 of the tumours (71%). CD44 was expressed in all 22 NBs with favourable prognoses (stages 1, 2 or 4S), but only 50% (15/30) of advanced NB (stages 3 and 4) (P < 10(-4)), suggesting that the absence, rather than the overexpression, of CD44 is a signal of tumour aggressiveness. The cumulative progression-free survival was significantly longer in patients with CD44 positive tumours compared with patients with CD44 negative tumours (P < 10(-5)). More importantly, progression-free survival was also significantly higher in CD44 positive patients within the high-risk group (P < 0.01). In univariate analysis, we tested the prognostic value of tumour expression of CD44 in comparison with tumour stage, age, tumour histology, and presence or absence of amplification of the MYCN protooncogene. All five measures had significant prognostic value. The expression of CD44 and the absence of MYCN amplification were the most powerful predictors of a favourable outcome. In a multivariate analysis of these measures, CD44 expression and tumour stage were the only independent prognostic factors for the prediction of patient survival. NB is the first clinical model described in which tumour aggressiveness correlates with repression rather than stimulation of CD44 expression. We recommend the use of CD44 as an additional biological marker in the initial staging of NB.

Adolescent↗

[CD44 expression: a new prognostic factor in neuroblastoma].

CD44 gene products are potential markers of aggressiveness in different tumor models, a result which prompted us to study clinical neuroblastoma (NB) specimens. CD44 expression was determined by immunostaining of 52 NB with a monoclonal antibody (J173) directed against an epitope common to all CD44 isoforms. All tumors were from patients (pts) with newly diagnosed NB treated with standardized protocols. They were classified according to international criteria [11]. CD44 immunoreactivity was detected in 37 tumors (71%). CD44 was expressed in 100% of favorable NB stages (1, 2 or 4S), but only 50% of advanced NB (stages 3 and 4) (p = 0.0001), suggesting that the absence rather that the overexpression of CD44 is a signal of tumor aggressiveness. The cumulative event-free survival was significantly longer in pts with CD44-positive tumors as compared to pts with CD44-negative tumors (p < 10(-5)). More importantly, progression-free survival was also significantly higher in CD44-positive pts within the high-risk group (p < 0.01). In univariate analyses, we tested the prognostic value of tumor expression of CD44 in comparison with tumor stage, age, tumor histology and presence or absence of N-myc proto-oncogene amplification. All five measures had significant prognostic value. The expression of CD44 and the absence of N-myc amplification were the most powerful predictors of a favorable clinical outcome. In a multivariate analysis of these measures, CD44 expression and tumor stage were the only independent prognostic factors for the prediction of patient survival. NB is the first clinical model described in which tumor aggressiveness correlates with a repression rather than a stimulation of CD44 expression. We recommend the use of CD44 as an additional biological marker in the initial staging of neuroblastoma.

Adolescent↗

Mutation in the COL2A1 gene in a patient with hypochondrogenesis. Expression of mutated COL2A1 gene is accompanied by expression of genes for type I procollagen in chondrocytes.

A new dominant mutation in the COL2A1 gene was found in a 38-week-old fetus with hypochondrogenesis. Denaturing gradient gel electrophoresis was used to analyze all 44 exons coding for the triple-helical domain of COL2A1 gene and the corresponding exon-intron boundaries. The technique detected a new sequence variation in exon 35. Sequencing of exon 35 demonstrated a single base mutation that converted the codon for glycine at position 604 to a codon for alanine. Electrophoresis of pepsin-digested collagen extracted from the diseased cartilage showed a doublet band of the alpha 1(II) chain of type II collagen and the presence of alpha 1(I) and alpha 2(I) chains of type I collagen. Two-dimensional analysis of cyanogen bromide peptides from the type II collagen revealed post-translational overmodification of peptides CB12, CB11, CB8, and CB10.5, whereas peptide CB9.7 migrated normally. Microscopic examination of cartilage showed that the mutation altered the organization of the growth plate. Also, articular chondrocytes contained large cisternae of rough endoplasmic reticulum. The density of the extracellular matrix was reduced, and the intensity of the staining with an antibody to type II collagen was diminished. In contrast, a significant staining with an antibody to type I collagen was observed. In situ hybridization with cRNA probes revealed a significant level of alpha 1(I) mRNA in the cytoplasm of the patient's chondrocytes. The signal for alpha 1(II) mRNA was about the same in control samples. The results indicated, therefore, that the genes for both type I and type II procollagens were simultaneously expressed in chondrocytes from the patient.

Adult↗

Desmoplastic small round cell tumors of the abdomen.

BACKGROUND: Desmoplastic small round cell tumors (DSRCT) have been only recently identified. METHODS: The authors report DSRCT in two pediatric patients (an 8-year-old boy and 12-year-old boy). In both patients, the initial diagnosis was rhabdomyosarcoma. The resistance to standard chemotherapy and radiation therapy prompted the authors to review the initial biopsy specimens and perform complementary immunophenotypic characterization. RESULTS: These analyses revealed that the tumor cells were strongly positive for keratin epithelial marker antigen, desmin, vimentin, neurospecific enolase, and S100 protein, corresponding to pleomorphic differentiation, characteristic of DSRCT: CONCLUSIONS: The authors suggest that extensive immunohistologic characterization be performed in all cases of small round cell tumors of the abdomen so that the diagnosis of DSRCT is not overlooked. These rare tumors are refractory to chemotherapy, and initial aggressive surgery is warranted.

Antigens, Neoplasm↗

Familial autoimmune enteropathy with circulating anti-bullous pemphigoid antibodies and chronic autoimmune hepatitis.

In a family of four children (two boys and two girls), the two brothers had severe, protracted watery diarrhea beginning at 2 and 3 weeks of life, respectively. Duodenal mucosa in both patients showed total villous atrophy and severe inflammatory infiltration of the entire bowel. The first patient also had lymphoid cell infiltration of the pancreas and died at 6 weeks of age. The second boy is alive at 2 years of age and is immunocompetent, but still receives total parenteral nutrition. Indirect immunofluorescence studies revealed circulating antibodies to enterocytes, smooth muscle, thyroid, and islet cells. Bullous pemphigoid antibodies (230 and 180 kd), specific for hemidesmosomal proteins and usually associated with a subepidermal blistering skin disease, were detected by direct and indirect immunofluorescence studies and by Western immunoblot. A diagnosis of autoimmune hepatitis was made, based on evidence of chronic active hepatitis and circulating anti-smooth muscle antibody. Immunosuppressive treatments induced partial clinical remission of the diarrhea but no resolution of the small bowel injury. At 16 months of age, remission of the diarrhea occurred, but persistent autoimmune hepatitis led us to maintain treatment with prednisone and azathioprine, and later with cyclosporine. In this child, as in other patients with autoimmune disease, the link between autoantibodies and organ damage remains uncertain but immunosuppressive treatment is indicated.

Autoantibodies↗

[Melanosis of the prostate. A new case and review of the literature].

Melanin may be found within fibromuscular prostatic stroma and/or in prostatic epithelium. An example of prostatic melanosis, with histochemical and immunohistochemical studies is reported. The pathologic description and the histogenesis of this rare entity are discussed.

Humans↗

[Non-seminomatous germ cell tumors of the testis. Role of the pathologist in the assessment of prognostic factors based on the specimen of orchiectomy. Proposal of an anatomopathological examination report defined by the Study Group of the Committee of Cancerology of the French Association of Urology].

Non-seminomatous germ cell tumors of the testis. Role of the pathologist in the definition of the prognostic factors based on examination of the orchidectomy specimen. Proposal of a pathological examination report form defined by the study Group of the Oncology Committee of the French Urological Association.

Carcinoma, Embryonal↗

[Ectopic deposits of Tamm-Horsfall protein. A psuedo-tumoral lesion].

Three cases of unusual deposits of Tamm-Horsfall protein in peripelvic and perirenal fat tissue are reported. A renal tubular rupture leads to the deposition of this protein. In the first case, the association of the deposits with epithelial structures, raised the possibility of a bladder carcinoma infiltration. These deposits simulated on the X-ray examination, a pelvis neoplasm in our second patient and a tuberculosis in the third case. However the particular microscopic appearance of Tamm-Horsfall protein, its intense staining with the periodic-acid-Schiff, and its positivity with a specific antibody led to the diagnosis.

Adipose Tissue↗