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M D'herbomez

Publications and source records attributed to M D'herbomez.

5 recordsLinked to original sources
PubMed2001

Pseudohypoparathyroidism Ia and hypercalcitoninemia.

Pseudohypoparathyroidism Ia (PHP Ia) is characterized by resistance to PTH and many other stimuli because of deficiency of stimulatory G protein alpha-subunit. To determine the incidence, natural history, and mechanism of C cell dysfunction in PHP, calcitonin assays were performed in six patients with PHP Ia and four with pseudopseudohypoparathyroidism from three unrelated families. Controls included healthy subjects and patients with PHP Ib or hypoparathyroidism. The mean basal level of calcitonin was higher in PHP Ia patients than in controls (95.3 +/- 112.7 vs. 3.7 +/- 2.4 pg/mL; P = 0.005; n < 10). In PHP Ia patients, calcitonin levels rose over the normal range (30 pg/mL) after pentagastrin infusion in five patients and remained normal in one. Familial medullary thyroid carcinoma was clinically, biologically, and ultrasonographically ruled out over a mean follow-up exceeding 3 yr. Genomic screening for RET protooncogene mutations failed to reveal any anomaly. The calcitonin infusion test, which induced a significant increase in plasma cAMP in controls 30 and 60 min after infusion, failed to produce this response in PHP Ia patients, suggesting that the action of calcitonin was specifically impaired. PHP Ia may therefore be an independent etiology of hypercalcitoninemia and hyperresponsiveness to pentagastrin infusion.

Adult↗
PubMed2001

Lingual thyroid. A case report.

We describe an unusual clinical case in which a non functional cervical thyroid coexisted with a functional ectopic lingual thyroid. A twenty-year-old woman was referred for hypothyroidism treated with L-thyroxin related to a basilingual tumor diagnosed 8 years previously. Oropharyngeal examination showed a spherical basilingual tumor 2.5 cm in diameter. Laboratory findings during treatment with 50 microgram of L-thyroxin daily showed: TSH 6,280 microIU/ml (N: 4,4 to 3.6), FT3 4,2 pmol/l (N: 3.3 to 5.1), and FT4 15.4 pmol/l (N: 10,5 to 25,5). Antithyroid antibodies were absent. Cervical ultrasonography showed a small hypoechogenic, heterogeneous orthotopic thyroid gland confirmed by cervical computed tomography thyroid. An I(123) scan revealed uptake above the chin on the profile, and no significant uptake is the area of the normal thyroid. The lack of iodine uptake by the cervical thyroid remains unexplained. In conclusion, this report of an ectopic thyroid location in unusual because of the coexistence of non functional cervical thyroid and of a partially functional lingual thyroid tissue. The pathogenesis of this association remains unclear.

Adult↗
PubMed2000

Resistance to thyroid hormone in a family with no TRbeta gene anomaly: pathogenic hypotheses.

UNLABELLED: Syndromes of resistance to thyroid hormone (RTH) are almost always linked to a defective triiodothyronine-receptor B gene (TRB). Only six families with RTH exhibiting a normal TRB gene have been reported so far. We report another and discuss possible mechanisms. PATIENTS AND METHODS: We studied a kindred expressing a typical RTH phenotype. DNA was amplified and the TRB gene was sequenced. Linkage analysis assessed linkage between the TRB gene and RTH phenotype. RESULTS: Direct sequencing of the TRB gene failed to identify any anomaly in the coding exons. Linkage analysis demonstrated that the RTH phenotype was not linked to the TRB gene in this family. CONCLUSION: TRB1 and TRB2 genes were not defective in this family. Multiple mechanisms might account for this situation at the pre-receptor, receptor and post-receptor levels. The most likely hypothesis is the involvement of an abnormal nuclear cofactor serving a specific function in the regulation of thyroid hormone action.

Adult↗
PubMed1999

Human pancreatic islet quality control: easy assessment of metabolic functions.

We describe simplified and rapid methods to assess islet function with the aim to develop better protocols for islet isolation and to determine islet characteristics before transplantation. These methods are also useful in the assessment of the potentially beneficial or deleterious effects of compounds added to the culture media in stimulation experiments. To this end, we took advantage of the multiscreen assay system produced by Millipore SA. This 96-well unit allowed the free-floating culture of islets on filter membranes, the rapid vacuuming and collection of conditioned media or reaction buffer and thus successive testing of the same number of islets, possibly at different culture times. We estimated islet viability by determination of the metabolic activity of cells, normal function of islets by their ability to metabolize glucose and to synthesize and secrete insulin and of nitrite release, a reflection of nitric oxide (NO) status of cells, which may be involved in a signaling pathway during glucose-stimulated insulin secretion or in cytokine inducible pathway. Assays may be performed either on selected islets or on aliquots of semi-purified preparations designated for grafting, allowing thus the rapid estimation of graft function of the entire preparation. This herein described system may be also extended to many other functional tests.

Automation↗