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Biomedical subjects

J Barbier

Publications and source records attributed to J Barbier.

At least 19 recordsLinked to original sources

Alterations of beta3-adrenoceptors expression and their myocardial functional effects in physiological model of chronic exercise-induced cardiac hypertrophy.

Physical training induces cardiovascular autonomic nervous system regulation adaptations, which could result from beta adrenergic receptor (AR) modifications. Among them, beta(3 )AR alterations have been recently reported but their functional effect remained to discuss. To explain the beta(3) AR gene expression in relation to function, we simultaneously studied the left ventricle (LV) beta(3) AR mRNA and protein levels and the myocardial functional effects of a beta(3) AR agonist following physical training. Forty rats were assigned to either a control (C; N = 20) or a trained (T; N = 20) group. The treadmill running protocol was performed for 8 weeks. Histological measurements on LV slices were quantified. The beta(3) AR mRNA abundance was studied with RT-PCR and beta(3) AR protein density with Western-Blot analysis. Myocardial functional effects of a beta(3) AR agonist, BRL37344 (10(-8) M), were studied in Langendorff-perfused hearts. Histological data confirmed the adapted patterns of the physiological cardiac hypertrophy observed in T (P < 0.01), with a significant increase in arteries density (P < 0.01) and an unchanged collagen concentration. The beta(3) AR protein density was increased in T (154 +/- 38% in T vs. 100 +/- 24% in C; P < 0.05), but no change was noted concerning the beta(3) AR mRNA level. After BRL37344 perfusion LVDP, +dP/dT and -dP/dT, in C (P < 0.01), and only +dP/dT in T (P < 0.05) were decreased. Moreover, all LV hemodynamic parameters were more altered after BRL37344 in C than in T (P < 0.01).Thus, in this physiological model of cardiac hypertrophy, an increase of beta(3) AR density without beta(3) AR mRNA alteration was observed. Classical negative myocardial lusitropic and inotropic effects induced by a specific agonist of beta(3) AR were diminished in trained rats.

Animals↗

[Severe angular deformity of the humerus: unilateral external fixation for correction and bone lengthening].

We report the case of a 10-year-old child who presented a severely deformed upper limb due to post-traumatic partial proximal epiphysiodesis of the humerus. The goal of treatment was to correct the severe angular deformity, prevent recurrence, and lengthen the humerus 6 cm. We used the De Bastiani callotasis method with osteotomy of the humeral shaft and unilateral external fixation (Orthofix LRS). The bony deformations were corrected progressively. Angular correction induced a geometric lengthening sufficient to match the length of the healthy limb. Lengthening index was 22.7 days/cm. The functional and esthetic results were remarkable. Complementary epiphysiodesis of the proximal physis successfully prevented recurrent deformation.

Anthropometry↗

[Fracture-dislocation of the second carpometacarpal joint. Case report and review of the literature].

A 26-year-old man was involved in a car crash then he presented an isolated trauma of the hand. We found out a dorsal dislocation of the second carpometacarpal joint with trapezoid fracture and a Rolando fracture. In emergency, closed reduction with percutaneous wires to stabilize, was performed. In the same time, the Rolando fracture was treated by internal fixation (plate). In a second time, after computerized tomography of the carpus, the trapezoid was reduced through a dorsal incision and held with two Kirschner-wires. At last follow-up one year after injury, the result was good. All movements of the wrist and fingers were full and pain free. Thumb index pinch and grasp were approximately 80% those of the uninjured hand. The mechanisms of injury, anatomic factors and management of seventy-one cases of similar trauma (included at least a dislocation of the second carpometacarpal joint) were reviewed in the literature.

Accidents, Traffic↗

Multicentre study of thyroid nodules in patients with Graves' disease.

BACKGROUND: The association of Graves' disease with thyroid nodules and thyroid carcinoma is rarely reported. The incidence seems to be increasing according to recent literature. The aim of this multicentre study was to review patients who had surgery for Graves' disease associated with thyroid nodules, and to evaluate the risk of thyroid carcinoma. METHODS: A retrospective study was made of 557 consecutive patients who underwent operation for Graves' disease between 1991 and 1997 in five endocrine surgery departments. Each patient underwent clinical, biochemical, ultrasonographic and scintigraphic evaluation. None of the patients had had previous radioactive iodine therapy or external irradiation. Surgery consisted of either a subtotal or total thyroidectomy. RESULTS: Nodules were observed before operation in 140 patients (25.1 per cent). Thyroid carcinoma was diagnosed in 21 patients (15.0 per cent), always inside a nodule. The incidence of thyroid carcinoma associated with Graves' disease was 3.8 per cent (21 of 557 patients): 20 papillary and one follicular carcinoma. The carcinoma was multifocal in two patients. Tumour diameter ranged from 2 to 25 mm. A nodule was palpable in four patients. CONCLUSION: This multicentre study of patients having thyroidectomy for Graves' disease showed that 3.8 per cent had a carcinoma; the rate of carcinoma in cold nodules was 15.0 per cent. Surgery should be advised in any patient with Graves' disease and a thyroid nodule; the operation should be total thyroidectomy.

Adolescent↗

A new orthoborate, Sr3Ga3(BO3)4O(OH)

The crystal structure of tristrontium trigallium tetraborate oxide hydroxide has been determined by X-ray diffraction using a crystal grown by hydrothermal crystallization of a strontium gallo-borate glass. It represents a new orthoborate structure type built of complex layers formed by BO(3) triangles sharing corners with Ga(2)O(7) tetrahedral dimers and GaO(4)OH square pyramids. The Sr atoms occupy both inter- and intralayer sites.

Journal Article↗

Structure of the defect perovskite Ce1/3NbO3: a redetermination by electron and neutron powder diffraction

The crystal structure of the defect perovskite Ce1/3NbO3, cerium niobium oxide, has been re-examined by neutron powder and electron diffraction. The results of a powder neutron Rietveld refinement indicate that the structure is monoclinic: space group P2/m with Z = 4, a = 5.5267 (3), b = 7.8824 (2), c = 5.5245 (3) A, beta = 90.294 (1)degrees, V= 240.67 (2) A3 at 298 K with chi2 = 2.570. Previous reports have described the Ce1/3NbO3 structure in a smaller (V/2) orthorhombic cell based solely upon X-ray powder diffraction data. The presence of weak reflections in the electron diffraction pattern provides conclusive evidence for a monoclinic superstructure of the orthorhombic cell. While these superlattice reflections are barely detectable with X-ray radiation, they are clearly visible in the neutron diffraction experiments. The superlattice reflections are shown to arise from a tilting of the NbO6 octahedra which results in the reduction of symmetry from orthorhombic to monoclinic. It is also found that the Ce3+ and Nb5+ cations are displaced from the centres of their respective polyhedra to accommodate the bond-valence requirements of the crystal structure. It is likely that distortions of this type are present in other Ln1/3NbO3 and Ln1/3TaO3 defect perovskites.

Journal Article↗

Stimulation of femoral trabecular bone growth in ovariectomized rats by human parathyroid hormone (hPTH)-(1-30)NH(2).

It has been proposed that intermittent bursts of adenylyl cyclase and the surges of cyclic AMP (cAMP) they produce can trigger PTH's bone anabolic action without the activation of phospholipase-C (PLC). This was based on the osteogenic action in ovariectomized (OVX) rats of hPTH-(1-31)NH(2), which can stimulate adenylyl cyclase but not PLC in ROS 17/2 rat osteosarcoma cells, and the osteogenic impotence of fragments such as 1-desamino-hPTH-(1-34) and hPTH-(8-84) which strongly stimulate PLC but not adenylyl cyclase. But this seems to have been disproven by the inability of hPTH-(1-30)NH(2) to stimulate bone growth despite its having hPTH-(1-31)NH(2)'s ability to strongly stimulate adenylyl cyclase but not PLC in cells with rat type1 PTH/PTHrP receptors. Because of the importance of hPTH-(1-30)NH(2)'s apparent osteogenic impotence for knowing how PTH triggers bone growth, we have reinvestigated the fragment's ability to stimulate trabecular bone growth in the femurs of young OVX rats and have found it to be strongly osteogenic at doses 2-10 times higher than the highest dose used previously. Thus, 6 weeks of once-daily subcutaneous injections of 10-50 nmol of hPTH-(1-30)NH(2)/100 g of body weight into young rats starting 2 weeks after OVX significantly increased the femoral trabecular volume and mean thickness of individual trabeculae above those in sham-operated control rats. In OVX rats treated with 50 nmol of hPTH-(1-30)NH(2)/100 g of body weight, the trabecular volume was 2.6 times higher and the mean trabecular thickness nearly 4 times higher than in the sham-operated control rats. This very large increase in the mean trabecular thickness was as much as the increase induced by 2 nmol/100 g of body weight of hPTH-(1-31)NH(2), [Leu(27)]cyclo(Glu(22)-Lys(26))-hPTH-(1-31)NH(2), hPTH-(1-34)NH(2) and [Leu(27)]cyclo(Glu(22)-Lys(26))-hPTH-(1-34)NH(2). These results have removed a major objection to the proposal that PTH's osteogenic action in rats can be triggered solely by intermittent surges of cAMP and the bursts of cAMP-dependent protein kinase activity they cause.

Animals↗

[Human "pancreatic" bladder. Two case reports].

The aim of this study is to report two similar cases with an "accessory biliary duct" confluent to the main pancreatic duct. There was pancreatic juice inside the "gallbladder". There was no connection between "accessory biliary duct" and intra or extrahepatic biliary ducts. This anomalous junction of the "cystic duct" and the main pancreatic duct may be explained by embryology. These two cases could be the first human "pancreatic" bladders reported.

Bile Ducts↗

Mapping of a gene predisposing to familial thyroid tumors with cell oxyphilia to chromosome 19 and exclusion of JUN B as a candidate gene.

BACKGROUND: Familial nonmedullary thyroid carcinoma (FNMTC) is a clinical entity characterized by a more aggressive phenotype than the sporadic counterpart. The transmission of susceptibility of FNMTC is compatible with autosomal dominant inheritance. We report the identification of a new entity of FNMTC and the mapping of the responsible gene named TCO (for thyroid tumor with cell oxyphilia). METHODS: In one family, multinodular goiters were diagnosed in six individuals and papillary thyroid carcinoma was diagnosed in three. Eight patients were operated on. Blood samples were collected from the nine affected patients and from eight unaffected relatives. The gene was mapped by linkage analysis with a whole-genome panel of microsatellite markers. RESULTS: The neoplastic cells from all lesions showed characteristic faint to marked cytoplasmic oxyphilia. We found a logarithm of odd ratio (LOD) score of 2.41 at theta = 0 for marker D19S586. Additional markers were typed in the region and were found to be in linkage, with LOD scores peaking at markers D19S916 (Zmax = 3.01 at theta = 0) and D19S413 (Zmax = 2.95 at theta = 0). All these markers have been physically mapped to 19p13.2. CONCLUSIONS: TCO was mapped to chromosome 19p13.2. Interestingly, both the benign and malignant thyroid tumors in this family exhibit some degree of oxyphilia, which has not been described until now in the familial forms of NMTC.

Adenoma, Oxyphilic↗

A gene predisposing to familial thyroid tumors with cell oxyphilia maps to chromosome 19p13.2.

Familial nonmedullary thyroid cancer (FNMTC) is a clinical entity characterized by a phenotype more aggressive than that of its sporadic counterpart. Families with recurrence of nonmedullary thyroid cancer (NMTC) have been repeatedly reported in the literature, and epidemiological data show a very high relative risk for first-degree relatives of probands with thyroid cancer. The transmission of susceptibility to FNMTC is compatible with autosomal dominant inheritance with reduced penetrance, or with complex inheritance. Cases of benign thyroid disease are often found in FNMTC kindreds. We report both the identification of a new entity of FNMTC and the mapping of the responsible gene, named "TCO" (thyroid tumors with cell oxyphilia), in a French pedigree with multiple cases of multinodular goiter and NMTC. TCO was mapped to chromosome 19p13.2 by linkage analysis with a whole-genome panel of microsatellite markers. Interestingly, both the benign and malignant thyroid tumors in this family exhibit some extent of cell oxyphilia, which, until now, had not been described in the FNMTC. These findings suggest that the relatives of patients affected with sporadic NMTC with cell oxyphilia should be carefully investigated.

Adenoma, Oxyphilic↗

[Basedow's disease and thyroid nodules. A common association].

The frequency of thyroid cancer associated with Graves' disease is a controversial subject. The authors retrospectively studied 110 consecutive patients operated for Graves' disease between 1991 and 1996. Each patient was evaluated by clinical and laboratory examination, ultrasound and isotope scan. None of the patients had a history of external beam cervical radiotherapy or radioactive iodine. All patients were treated by total or subtotal thyroidectomy. Thyroid nodules were detected in 28 patients (24 women, 4 men), and 6 of them corresponded to papillary carcinoma (5.5% of patients with Graves' disease and 21.4% of patients with Graves' disease associated with nodules). These data suggest the value of surgery in Graves' disease associated with thyroid nodules.

Adult↗

Comparison of the abilities of human parathyroid hormone(1-31)NH2 and human parathyroid hormone-related protein(1-31)NH2 to stimulate femoral trabecular bone growth in ovariectomized rats.

N-terminal fragments of PTH and PTHrP, such as hPTH-(1-34) and hPTHrP-(1-34), are sufficiently similar with respect to amino acid sequence, location of functional domains, and higher order configuration to activate the same PTH/PTHrP receptor and the same two signal enzymes, adenylyl cyclase and phospholipase-Cbeta. Therefore, it was expected that hPTHrP-(1-31)NH2 would stimulate bone growth in ovariectomized rats as strongly as hPTH-(1-31)NH2. Like hPTH-(1-31)NH2, hPTHrP-(1-31)NH2 stimulated adenyly cyclase in ROS 17/2 osteosarcoma cells as strongly as the standard hPTH-(1-34) and like hPTH-(1-31)NH2, triggered a large drop in mean blood pressure when injected intravenously. Unlike hPTH-(1-31)NH2, however, hPTHrP-(1-31)NH2 could not stimulate trabecular growth in the distal femurs of young, sexually mature, ovariectomized rats.

Adenylyl Cyclases↗

Postthyroidectomy analgesia: morphine, buprenorphine, or bupivacaine?

STUDY OBJECTIVE: To compare three analgesic regimens for pain relief after thyroidectomy. DESIGN: Randomized, double-blind, placebo-controlled study. SETTING: Inpatient anesthesia in a university department of endocrine surgery. PATIENTS: 342 patients scheduled for elective thyroidectomy with nitrous oxide-oxygen-isoflurane anesthesia in addition to fentanyl. INTERVENTIONS: Group 1 received preoperative oral controlled release morphine 10 mg, and Group 2 received postoperative sublingual buprenorphine 0.2 mg. Group 3 received 0.25% bupivacaine (10 ml) wound infiltration before skin closure. Eight hours after tracheal extubation, patients received a second dose of the same drug in each group except in Group 3, where medication was changed to sublingual buprenorphine 0.2 mg. MEASUREMENTS AND MAIN RESULTS: Patients in Group 2 required fewer additional analgesics: 0.54 +/- 0.68 vs. 0.96 +/- 0.84 in Group 1 and 0.79 +/- 0.78 in Group 3. Patients in Group 2 demonstrated a better pain score and this group showed a higher percentage of satisfied patients: 96% vs. 85% in Group 1 and 91% in Group 3. Group 2 also included more patients requiring no analgesics: 56% vs. 32% in Group 1 and 42% in Group 3. The side effects in all three groups did not differ. CONCLUSION: The administration of sublingual buprenorphine after thyroidectomy provides better analgesia than small doses of oral controlled-release morphine or than 0.25% bupivacaine wound infiltration at the end of surgery.

Administration, Sublingual↗

Endosonographic features of esophageal granular cell tumors.

BACKGROUND AND STUDY AIMS: Granular cell tumors of the esophagus are rare tumors. A definite diagnosis is achieved by endoscopic biopsies in only 50% of cases. Endoscopic ultrasonography (EUS) is the best procedure in the evaluation of upper gastrointestinal tract submucosal tumors. The aim of this study was to describe the endosonographic findings of esophageal granular cell tumors. METHODS: From January 1989 to March 1994, 15 patients with 21 granular cell tumors which had negative biopsies were examined by EUS (Olympus GF UM3 or GF UM20,7,5 and 12 MHz). In five cases, the tumor was also studied with a 20 MHz Olympus miniprobe. The final histological diagnoses were obtained by subsequent endoscopic snare resection in 20 cases and surgically in one case. RESULTS: The endosonographic features (with the GF UM3 or GF UM20) of esophageal granular cell tumors were: a) a tumor size of less than 2 cm in 95% of cases; b) an hypoechoic solid pattern in 100% of cases; c) a tumor arising in the inner layers in 95% (second echo-poor layer n=15; third echo-rich layer n=5). In one case, the endosonographic finding was transmural malignant infiltration of the esophageal wall (histologically confirmed). CONCLUSION: When a granular cell tumor of the esophagus is suspected, EUS can show the inner layer location of the tumor and thus contribute to planning the endoscopic resection or follow up. When the tumor also invades the outer layers, EUS can contribute to planning the surgical resection.

Endosonography↗

Expression, localization, and thyrotropin regulation of cathepsin D in human thyroid tissues.

Enzymatic activity and isoform expression of cathepsin D (cath D) were studied in 107 cytosols from various human thyroid tissues including 21 normal tissues, 12 cold benign nodules, 17 toxic adenomas, 22 samples from Graves' disease patients, and 35 thyroid carcinomas. Cath D assay was optimized for human thyroid tissues. We found that mean cath D specific activities, expressed as units per milligrams protein minus thyroglobulin, were higher in carcinomas (P = 0.0001), toxic adenomas (P = 0.0001), and specimens from Graves' disease patients (P = 0.0001) than in normal thyroid tissues. Mean cath D activity in carcinomas was also significantly different from that in cold benign nodules (P < 0.001) and Graves' disease tissues (P < 0.05) but not from that of toxic adenomas. To determine possible mechanisms by which the observed increase in cath D activity might be regulated, we used Western blotting to measure relative amounts of cath D isoforms in the various thyroid tissues. We found that the 31-kDa major processing form of cath D was significantly increased in carcinomas and toxic adenomas compared with normal tissues (P < 0.01), cold benign nodules (P < 0.05), and Graves' disease tissues (P < 0.05). A positive correlation of cath D activity with relative expression of the 31-kDa form (r = 0.67, P = 0.0001) was observed in 104 thyroid cytosols. These data demonstrate a deregulation at the protein level, with resulting increases in cath D activity. Immunogold labeling of cath D showed particle concentration in lysosomes or phagosomes in both normal follicles and papillary carcinoma cells, indicating that cath D localization was not altered by malignant transformation in human thyroid cells. TSH induced cath D synthesis and secretion in extracellular fluid of normal human thyroid cells in primary culture; TSH had little effect on intracellular cath D level. In conclusion, TSH-induced cath D synthesis may explain high cath D levels in Graves' disease tissues and toxic adenomas, because these tissues possess a permanently stimulated cAMP transduction pathway. Furthermore, the overexpression of cath D in thyroid carcinomas in comparison with normal controls adds further arguments for the potential role of cath D in tumor growth and metastasis.

Adult↗

[Thyroid nodules associated with Graves' disease: another argument for surgical treatment].

Much controversy surrounds the incidence of thyroid cancer associated with Graves' disease. We studied retrospectively 110 patients operated on for Graves' disease between 1991 and 1996. Each patient was evaluated by clinical exam, biological test, ultrasonography, and scintigraphy. No patient had a history of prior external radiation to the head or the neck. All patients underwent near total or total thyroidectomy. Nodules in the thyroid were detected in 28 cases: 6 were papillary carcinoma (5.5% from patients with Graves' disease, and 21.4% from patients with Graves' disease associated with thyroid nodules). These data suggest interest of surgery in Graves' disease associated with thyroid nodules.

Graves Disease↗

[Technique for protecting the liver graft less tolerant than the small bowel to heat-induced ischemia in experimental liver + small bowel transplantation in swine].

Multivisceral and orthotopic liver/small bowel transplantations have been performed to treat patients with intestinal failure associated with liver failure induced by parenteral nutrition. The aim of this experimental study was to determine the experimental liver-small bowel harvesting and transplantation technique that achieves the best compromise between liver and intestine ischemia times in pigs. Initial portal revascularization of the liver which reduces the hepatic warm ischemia time after cold ischemia preparation of the graft immersed in lactated ringer's solution at 4 degrees C, reduce the risk of primary non function of the graft.

Animals↗