Karen M. Tordjman

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De novo lipogenesis is an energy-expensive process whose role in adult mammals is poorly understood. We generated mice with liver-specific inactivation of fatty-acid synthase (FAS), a key lipogenic enzyme. On a zero-fat diet, FASKOL (FAS knockout in liver) mice developed hypoglycemia and fatty liver, which were reversed with dietary fat. These phenotypes(More)
OBJECTIVE Hyperprolactinaemia in humans may be associated with a high prevalence of obesity but the nature of this link is poorly defined. The aim of this study was to establish the relationship between hyperprolactinaemia and body weight in patients with prolactin-secreting pituitary tumours. DESIGN We conducted a retrospective study of prolactinoma(More)
The majority of pituitary tumors are of monoclonal origin; however, the molecular basis for their formation is poorly understood. Somatic mutations in the alpha-subunit of the GTP-binding protein, Gs alpha (gsp oncogene) have been found in about one third of GH-secreting tumors. Mutations in another alpha-subunit of a GTP-binding protein, Gi2 alpha (gip(More)
OBJECTIVE There is no consensus as to the optimal postoperative treatment of patients with clinically nonfunctioning pituitary adenomas (NFPA) in whom total tumour removal has not been achieved. In this study we assessed whether dopamine agonist (DA) treatment can prevent postoperative remnant enlargement in NFPA. DESIGN AND METHODS Thirty-three patients(More)
The role of the low dose (1 microgram) ACTH stimulation test in the evaluation of patients with pituitary diseases was systematically assessed by relating its results to those obtained on gold standard tests of hypothalamo-pituitary-adrenal (HPA) reserve, such as insulin-induced hypoglycemia or a metyrapone challenge. Ten patients with pituitary diseases (8(More)
OBJECTIVE We have shown previously that in contrast to the standard high-dose 250-microgram ACTH test, a low-dose 1-microgram ACTH stimulation test correctly identified all patients with pituitary disease who had impaired hypothalamo-pituitary-adrenal (HPA) function. In this study we further compared the performances of these two tests as screening(More)
CONTEXT The diagnostic value of tests for detecting hypothalamic-pituitary adrenal insufficiency (HPAI) is controversial. OBJECTIVE Our objective was to compare standard-dose and low-dose corticotropin tests for diagnosing HPAI. DATA SOURCES We searched the PubMed database from 1966-2006 for studies reporting diagnostic value of standard-dose or(More)
PTH-induced osteoblast proliferation may contribute to its anabolic effects in bone. Since PTH-dependent osteoblast-like cell (Ob) growth is mediated via protein kinase C (PKC) and MAP kinase-kinase (MEK) and since lipoxygenase (LO) products activate PKC in a number of cell types, we assessed the expression of LO pathways in primary human cultured Ob. Ob(More)
We have demonstrated previously that rat adipose tissue showed sex and depot-specific responses to gonadal steroids. The epididymal fat pad in males responded exclusively to androgens by increased specific activity of the brain type isozyme of creatine kinase (CK). In females, the parametrial adipose tissue responded exclusively to estrogens. The present(More)
Lipoprotein lipase (LPL) provides tissues with fatty acids, which have complex effects on glucose utilization and insulin secretion. To determine if LPL has direct effects on glucose metabolism, we studied mice with heterozygous LPL deficiency (LPL+/-). LPL+/- mice had mean fasting glucose values that were up to 39 mg/dl lower than LPL+/+ littermates.(More)