bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thyrotropin Receptor Autoantibodies in Serum Are Present at Much Lower Levels Than Thyroid Peroxidase Autoantibodies: Analysis by Flow Cytometry*
Authors: Jaume Juan Carlos , Kakinuma Ayumu , Chazenbalk Gregorio D. , Rapoport Basil , McLachlan Sandra M. 
Published: January 2014

Abstract
Using Chinese hamster ovary (CHO) cells that express high numbers of TSH receptor (TSHR) on their surface, we studied the feasibility of detecting directly by flow cytometry the binding of autoantibodies in patients’ sera to the native TSHR. After using a serum (BBl) with high potency in the TSH binding inhibition (TBI) assay to establish the protocol, we studied an additional 38 sera: 10 without TBI activity (1–4.2% inhibition), 10 with moderately high TBI values (17.3–39.4% inhibition), 10 with high TBI levels (52–95.1% inhibition), 4 from normal individuals without autoimmune thyroid disease, and 4 from patients with systemic lupus erythematosus. We observed that a number of sera, including some without thyroid autoantibodies, contain antibodies against unknown antigens on CHO cells. Preadsorption with untransfected CHO cells before addition to the TSHR-10,000 cells eliminated or greatly reduced this nonspecific background. None of the sera from normal individuals, subjects with negative TBI values, or patients with systemic autoimmunity generated a positive signal on flow cytometry with TSHR-10,000 cells relative to the signal on untransfected cells. Remarkably, only 4 of 21 TBI-positive sera (including BBl) unequivocally recognized the TSHR on flow cytometry. In contrast, when thyroid peroxidase (TPO) autoantibodies in the same sera were studied using CHO cells overexpressing TPO on their surface, all 20 sera with TPO autoantibodies clearly elicited positive net fluorescence relative to untransfected cells. Study of the potent serum, BBl, revealed similar fluorescence (∼250 U) for TPO autoantibodies and TSHR autoantibodies at dilutions of 1:1000 and 1:10, respectively. Thus, by flow cytometry, the titer of TPO autoantibodies in the BBl serum is about 100-fold higher than that for TSHR autoantibodies in the same serum.
In conclusion, the present data provide the strongest support for the idea that TSHR autoantibodies in the sera of patients with autoimmune thyroid disease are present at much lower levels than are TPO autoantibodies. This finding has important implications for the diagnostic detection of TSHR autoantibodies and for understanding the pathogenesis of Graves’ disease.
The Differential Expression of Hepatocyte Growth Factor and Met in Human Placenta*
Authors: Kauma Scott , Hayes Natalie , Weatherford Shannon 
Published: January 2014

Abstract
Met is the tyrosine kinase receptor for the ligand hepatocyte growth factor (HGF). Met/HGF plays an important role in epithelial cell proliferation, migration, and morphogenesis. HGF also plays a crucial role in placental development in the mouse. To determine whether HGF potentially has a similar role in human placental development, the production and localization of Met and HGF were determined in early second trimester and term placentas. Reverse transcription-PCR using specific primers demonstrated the expression of Met and HGF messenger ribonucleic acid in placental villi. HGF production was determined by enzyme-linked immunosorbent assay. HGF production over 48 h by second trimester placental villous explants in culture (810 pg/mg total protein·h) was 2.1-fold greater than that in term placental villous explants (380 pg/mg total protein·h; P &lt; 0.01). Isolated trophoblast did not produce HGF, whereas isolated villous core tissues and villous core mesenchymal cells did produce HGF. Interleukin-1β treatment of placental villi or coculture of villous core mesenchymal cells with isolated trophoblast cells did not stimulate HGF production. Using immunohistochemistry, HGF localized to the villous core compartment with no localization to the trophoblast. In contrast, Met localized mainly to cytotrophoblast. These findings suggest that HGF produced by the villous core may act in a paracrine fashion to regulate trophoblast development or function through the HGF receptor, Met.
Expression of Glucokinase in Glucose-Unresponsive Human Fetal Pancreatic Islet-Like Cell Clusters1
Authors: Tu Jian , Tuch Bernard E. 
Published: January 2014

AbstractGlucokinase (GK) is the glucose sensor in the adult β-cell, resulting in fuel for insulin synthesis and secretion. Defects in this enzyme in the β-cell are responsible for the genetic disorder maturity-onset diabetes of the young, with the β-cell being unable to secrete insulin appropriately when challenged with glucose. The human fetalβ -cell is also unable to secrete insulin when exposed to glucose, but whether GK is present and functional in this developing cell is unknown. To determine the expression of GK in human fetal pancreatic tissue, cytosolic protein was extracted from human fetal islet-like cell clusters (ICCs) at 17–19 weeks gestation and examined for protein content and enzyme activity. On Western blots, a single band corresponding to GK was seen at 52 kDa, and this was similar to that obtained from human adult islets. The maximal velocity (Vmax) of GK was less in fetal ICCs than that in adult islets (8.7 vs. 20.7 nmol/mg protein·h); similar Km values were found in both ICCs and islets. No attempt was made to determine which cells in an ICC contained GK. Glucose utilization was determined radiometrically; the Vmax of the high Km component was less in ICCs than in islets (31.3 pmol/ICC·h vs. 101.4 pmol/islet·h). Culture of ICCs for 3–7 days in medium containing 11.2 mmol/L glucose resulted in a 3.7-fold increase in the Vmax of GK and a 1.8-fold increase in glucose utilization. These enhanced activities of glucose phosphorylation and glycolysis, however, did not lead to the β-cell being able to secrete insulin when exposed to glucose. In conclusion, glucokinase is present and functional in human fetal ICCs, but the inability of the human fetal β-cell to secrete insulin in response to an acute glucose challenge is not due to immaturity of this enzyme.
Detection of an Activating Mutation of the Thyrotropin Receptor in a Case of an Autonomously Hyperfunctioning Thyroid Insular Carcinoma1
Authors: Russo Diego , Tumino Salvatore , Arturi Franco , Vigneri Paolo , Grasso Giuseppe , Pontecorvi Alfredo , Filetti Sebastiano , Belfiore Antonino 
Published: January 2014

Abstract
Thyroid carcinomas, even when well differentiated, usually appear as hypofunctioning at scintigraphy. We report a case of an aggressive insular thyroid carcinoma presenting as an autonomously functioning thyroid nodule and causing severe thyrotoxicosis. The tumor was metastatic to a cervical lymph node and both lungs.
An activating mutation of the TSH receptor gene in both the primary tumor and the lymph node metastasis was found, due to a base substitution at codon 633 (normal guanine at position 1896 replaced by cytosine CAC for GAC causing aspartic acid substitution by histidine). Other known oncogenes (gsp, ras, PTC/ret, trk, met, and p53) were not involved.
This is the first description of an activating TSH receptor mutation in a thyroid hyperfunctioning carcinoma in which an aggressive malignant phenotype coexisted with activation of the cAMP cascade and differentiated thyroid functions.
Effects of Adrenomedullin on the Human Adrenal Glands: An in Vitro Study
Authors: Andreis P. G. , Neri G. , Prayer-Galetti T. , Rossi G. P. , Gottardo G. , Malendowicz L. K. , Nussdorfer G. G. 
Published: January 2014

Abstract
Numerous lines of evidence indicate that adrenal medulla exerts a paracrine control on the secretory activity of the cortex by releasing catecholamines and several regulatory peptides. Adrenomedullin (ADM) is contained in adrenal medulla of several mammalian species, including humans. Thus, we investigated whether human ADM1–52 exerts a modulatory action on steroid secretion of human adrenal cortex in vitro. Dispersed adrenocortical cells (obtained from the gland tail deprived of chromaffin cells) and adrenal slices (including both capsule and medulla) were employed. ADM specifically inhibited angiotensin II-stimulated aldosterone secretion of dispersed cells and enhanced basal aldosterone production by adrenal slices, minimal effective concentrations being 10−7 and 10−9 mol/L, respectively. These effects of ADM were suppressed by the CGRP1 receptor antagonist CGRP8–37 (10−5 mol/L). Neither basal and ACTH-stimulated aldosterone secretion of dispersed cells nor agonist-enhanced aldosterone production by adrenal slices were affected by ADM, which also did not alter cortisol secretion of both types of adrenal preparations. ADM (10−6 mol/L) blunted the aldosterone secretagogue action of the Ca2+ ionophore A23187 (10−5 mol/L) on dispersed cells and adrenal slices. Theβ -adrenoceptor antagonist l-alprenolol (10−6 mol/L) suppressed aldosterone response of adrenal slices to 10−7 mol/L isoprenaline and ADM. ADM concentration dependently raised epinephrine and norepinephrine release by adrenal slices, minimal effective concentration being 10−9 mol/L. Collectively, these findings suggest that ADM, acting via the CGRP1 receptor subtype, exerts a direct inhibitory effect on angiotensin II-stimulated aldosterone secretion, which, when the integrity of adrenal tissue is preserved, is overcome and reversed by an indirect stimulatory action, conceivably involving the release of catecholamines by adrenal chromaffin cells.
Increased Concentration of Vascular Endothelial Growth Factor/Vascular Permeability Factor in Cyst Fluid of Enlarging and Recurrent Thyroid Nodules1
Authors: Sato Kanji , Miyakawa Megumi , Onoda Noritaka , Demura Hiroshi , Yamashita Tetsuji , Miura Masakazu , Kasajima Takeshi , Yamazaki Kazuko , Obara Takao 
Published: January 2014

AbstractHuman thyrocytes produce vascular endothelial growth factor (VEGF), a potent angiogenic factor, also known as vascular permeability factor (VPF), which increases vascular permeability. Based on the assumption that VEGF/VPF is involved in fluid accumulation in thyroid cysts, we determined the VEGF/VPF concentration in cyst fluids of thyroid nodules from 79 patients. VEGF/VPF was found to be abundantly present in the cyst fluids (0.02–183 ng/mL). There was no significant difference of VEGF/VPF concentration in the cyst fluid obtained from thyroid adenoma or from adenomotous goiter with cystic degeneration. Immunoreactive VEGF/VPF in cyst fluid was eluted mainly at 45 kDa, and stimulated endothelial cell proliferation, which was partially blocked by anti-VEGF/VPF antibody. The VEGF/VPF concentration in the cyst fluid obtained from patients who required repeated aspiration or underwent surgical resection because of recurrent accumulation (84.8 ± 58.3 ng/mL, mean ± sd, n = 18) was significantly higher than that in the cysts that regressed or disappeared after a single aspiration (4.3 ± 4.4 ng/mL, n = 12, P &lt; 0.001).These in vitro and clinical findings suggest that VEGF/VPF is at least partly involved in the accumulation of cyst fluid in thyroid nodules, and that a high VEGF/VPF concentration predicts rapid accumulation of the cyst fluid, possibly necessitating interventional treatment.
Increased 12-Lipoxygenase Expression in Breast Cancer Tissues and Cells. Regulation by Epidermal Growth Factor1
Authors: Natarajan Rama , Esworthy Robert , Bai Wei , Gu Jia-Li , Wilczynski Sharon , Nadler Jerry 
Published: January 2014

AbstractThe interaction of growth factors, such as epidermal growth factor (EGF) with their receptors, on breast cancer cells can lead to the hydrolysis of phospholipids and release of fatty acids, such as arachidonic acid, which can be further metabolized by the lipoxygenase (LO) pathway. Several LO products have been shown to stimulate oncogenes and have mitogenic and chemotactic effects. In this study, we have evaluated the regulation of 12-LO activity and expression in breast cancer cells and tissues. Leukocyte-type 12-LO messenger RNA (mRNA) expression was studied by a specific RT-PCR method in matched, normal, uninvolved and cancer-involved breast tissue RNA samples from six patients. In each of these six patients, the cancer-involved section showed a much higher level of 12-LO mRNA than the corresponding normal section. 12-LO mRNA levels also were greater in two breast cancer cell lines, MCF-7 and COH-BR1, compared with the nontumorigenic breast epithelial cell line, MCF-10F. The growth of the MCF-7 cells was significantly inhibited by two specific LO blockers but not by a cyclooxygenase blocker. Treatment of serum-starved MCF-7 cells with EGF for 4 h led to a dose-dependent increase in the formation of the 12-LO product, 12-hydroxyeicosatetraenoic acid. EGF treatment also increased the levels of the leukocyte-type 12-LO protein expression at 24 h. These results suggest that activation of the 12-LO pathway may play a key role in basal and EGF-induced breast cancer cell growth.
Serum α-Inhibin Levels in Polycystic Ovary Syndrome: Relationship to the Serum Androstenedione Level1
Authors: Pigny Pascal , Desailloud Rachel , Cortet-Rudelli Christine , Duhamel Alain , Deroubaix-Allard Delphine , Racadot André , Dewailly Didier 
Published: January 2014

Abstract
To date, only one study has demonstrated increased serum inhibin levels in women with polycystic ovary syndrome (PCOS). Moreover, no relationship between serum inhibin and either FSH or androgen levels has been noted. This lack of data could be due to 1) the heterogeneity of PCOS and the small sample size of previous studies, and/or 2) the complexity of circulating inhibin molecular forms, which hinders the precise evaluation of bioactive inhibin. In the present study,α -inhibin levels were assayed in the serum of 61 healthy women and 72 PCOS patients by means of an α-α enzyme-linked immunosorbent assay. Serum α-inhibin levels together with LH and androstenedione (A) levels were significantly increased in PCOS women (mean ± sd, 1.45 ± 0.55 vs. 0.94 ± 0.36 U/mL in controls; P &lt; 0.001). Moreover, simple and partial regression analysis demonstrated that serum A levels were positively and independently correlated to serum α-inhibin (r = 0.32; P &lt; 0.01) and LH levels (r = 0.48; P &lt; 0.001) in PCOS. The respective influences of α-inhibin and LH on A variability were 20% and 80%, as determined by multiple regression analysis. In conclusion, in agreement with recent in vitro data, our in vivo results argue for a role of inhibin in the hyperandrogenism of PCOS together with, but independently from, that of LH. Further studies are needed to determine whether this effect is produced by inhibin A and/or B.
Comparative Messenger Ribonucleic Acid Analysis of Immediate Early Genes and Sex Steroid Receptors in Human Leiomyoma and Healthy Myometrium
Authors: Lessl Monika , Klotzbuecher Michael , Schoen Silvia , Reles Angela , Stöckemann Klaus , Fuhrmann Ulrike 
Published: January 2014

To shed light on the molecular mechanisms involved in the pathogenesis of uterine leiomyomas, transcript levels of the immediate early genes c-fos, c-myc, and c-jun and of the estrogen receptor (ER) and progesterone receptor (PR) were determined in tissue samples of human myometrium and leiomyoma. The messenger RNA (mRNA) content was analyzed by RT-PCR. mRNAs for c-fos, c-myc, c-jun, ER, and PR were detected in all 18 samples of leiomyoma and corresponding myometrial tissue collected in this study. Interestingly, in contrast to healthy tissues, we found a distinct and significant reduction of c-fos mRNA in the tumor. These data were substantiated by the finding of lowered c-Fos protein levels in leiomyomas tissues. Moreover, transcripts of c-jun and c-myc were less abundant in most of the leiomyomas than in the myometrium. This different expression of the protooncogenes in leiomyomas and myometrium was independent of the phase of the menstrual cycle in which samples were collected. In contrast to the reduced transcript levels observed for the immediate early genes, the ER and PR mRNA contents of the leiomyomas and myometrium did not differ. These results were confirmed by immunohistochemical studies for ER and PR protein.
In conclusion, our data show that the deregulated expression of protooncogenes, especially of c-fos, is linked to the pathogenesis of leiomyomas. Confirmation of a potential role of downregulated c-fos levels for the benign character of these tumors requires further investigation. Additionally, the findings suggest that sex steroids do not influence the different expression patterns of c-fos, c-myc, and c-jun in leiomyomas, as compared with myometrium.
Methimazole and Propylthiouracil Equally Cross the Perfused Human Term Placental Lobule*
Authors: Mortimer R. H. , Cannell G. R. , Addison R. S. , Johnson L. P. , Roberts M. S. , Bernus I. 
Published: January 2014

Abstract
Propylthiouracil (PTU) is widely believed to cross the placenta less freely than methimazole (MMI) and is therefore regarded as the preferred drug for treatment of hyperthyroidism in pregnancy. Clinical studies comparing the two drugs show, however, no differences in maternal or fetal thyroid function. We investigated transfer from the maternal to the fetal circuit in the isolated perfused term human placental lobule of low and high doses of PTU (4 μg/mL and 40μ g/mL) and MMI (1.5 μg/mL and 15 μg/mL) in protein-free perfusate and low doses of both drugs with addition of 40 g/L of bovine albumin. Both drugs readily crossed the placenta, reaching equilibrium in all experiments in about 2 h. Drug concentrations in the two circuits fitted a two compartmental model. Transfer kinetics for the two drugs were similar, nonsaturable, and unaffected by addition of albumin. Clearances (mL·min−1·g−1, means ± sd) of PTU from maternal to fetal circuits were: 0.229± 0.110, 0.216 ± 0.065, and 0.170 ± 0.032; and for transfer of MMI: 0.165 ± 0.025, 0.232 ± 0.153, and 0.174 ± 0.009 (for low doses without, low doses with, and high doses without albumin, respectively). Clearances of PTU from fetal to maternal circuits were: 0.147 ± 0.072, 0.109 ± 0.014, and 0.116 ± 0.028; and for transfer of MMI: 0.095 ± 0.029, 0.122 ± 0.088, and 0.12 ± 0.005 (in the same experiments). There was no significant difference between drugs or drug doses and no effect of addition of albumin. We conclude that PTU and MMI have similar placental transfer kinetics.
Interleukin 1α Increases Serum Leptin Concentrations in Humans
Authors: Janik John E. , Curti Brendan D. , Considine Robert V. , Rager Helen C. , Powers Geraldine C. , Alvord W. Gregory , Smith John W. , Gause Barry L. , Kopp William C. 
Published: January 2014

Abstract
Leptin, the protein product of the ob gene, regulates appetite and body weight in animals. Endotoxin and cytokines, induced by endotoxin, interleukin (IL) 1 and tumor necrosis factor, increase expression of leptin in mice and hamsters. We measured serum leptin concentrations in patients with cancer before and after administration of recombinant human IL-1α. Fourteen patients received IL-1α at one of three dose levels (0.03, 0.1, or 0.3 μg/kg·day) for 5 days. Serum leptin concentrations increased in all but two patients within 24 h after the first dose. The increase in leptin was correlated directly with IL-1α dose (P = 0.0030). Despite continued administration of IL-1α, serum leptin concentrations returned to pretreatment levels by day 5 of therapy. An increase in serum leptin concentrations may be one mechanism by which anorexia is induced by IL-1α. However, tachyphylaxis of the leptin response suggests that other mechanisms also are involved.
Effect of Aging on the Sensitivity of Growth Hormone Secretion to Insulin-Like Growth Factor-I Negative Feedback*
Authors: Chapman Ian M. , Hartman Mark L. , Pezzoli Suzan S. , Harrell Frank E. , Hintz Raymond L. , Alberti K. G. M. M. , Thorner Michael O. 
Published: January 2014

Abstract
To determine the effect of aging on the suppression of GH secretion by insulin-like growth factor (IGF)-I, we studied 11 healthy young adults (6 men, 5 women, mean ± sd: 25.2 ± 4.6 yr old; body mass index 23.7 ± 1.8 kg/m2) and 11 older adults (6 men, 5 women, 69.5 ± 5.8 yr old; body mass index 24.2 ± 2.5 kg/m2). Saline (control) or recombinant human IGF-I (rhIGF-I) (2 h baseline then, in sequence, 2.5 h each of 1, 3, and 10 μg/kg·h) was infused iv during the last 9.5 h of a 40.5-h fast; serum glucose was clamped within 15% of baseline. Baseline serum GH concentrations (mean ± se: 3.3 ± 0.7 vs. 1.9 ± 0.5 μg/L, P = 0.02) and total IGF-I concentrations (219 ± 15 vs. 103 ± 19 μg/L, P &lt; 0.01) were higher in the younger subjects. In both age groups, GH concentrations were significantly decreased by 3 and 10 μg/kg·h, but not by 1μ g/kg·h rhIGF-I. The absolute decrease in GH concentrations was greater in young than in older subjects during the 3 and 10 μg/kg·h rhIGF-I infusion periods, but both young and older subjects suppressed to a similar GH level during the last hour of the rhIGF-I infusion (0.78 ± 0.24 μg/L and 0.61 ± 0.16 μg/L, respectively). The older subjects had a greater increase above baseline in serum concentrations of both total (306 ± 24 vs. 244 ± 14 μg/L, P = 0.04) and free IGF-I (8.5 ± 1.4 vs. 4.2 ± 0.6 μg/L, P = 0.01) than the young subjects during rhIGF-I infusion, and their GH suppression expressed in relation to increases in both total and free serum IGF-I concentrations was significantly less than in the young subjects. We conclude that the ability of exogenous rhIGF-I to suppress serum GH concentrations declines with increasing age. This suggests that increased sensitivity to endogenous IGF-I negative feedback is not a cause of the decline in GH secretion that occurs with aging.