bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insulin-Like Growth Factor I Receptors Are Expressed by the Enteroendocrine Cell Line STC-1: Relationship with Proliferation and Cholecystokinin Expression
Authors: Ye Fei , Chevrier Anne-Marie , Langlois Dominique , Cuber Jean-Claude , Saez Jose M. , Chayvialle Jean-Alain , Abello Jacques 
Published: April 2003

Receptors for insulin-like growth factors (IGF-I and IGF-II) are expressed in mammalian intestinal epithelium. No information on the presence of IGF receptors in intestinal endocrine cells is available. We tested for IGF-I receptors the endocrine cell line STC-1, which synthesizes and processes cholecystokinin (CCK) among other peptides, and assessed the effects of IGF-I on cell growth and CCK content. Cell monolayers in serum-free culture medium specifically bound [<sup>125</sup>I]IGF-I. Scatchard analysis was consistent with a single class of high affinity binding sites (K<sub>D</sub> = 0.91 n<i>M</i>; B<sub>max</sub> = 4,700 sites/cell). In competitive binding assays, unlabeled IGF-I, IGF-II and insulin displaced in a dose-dependent manner [<sup>125</sup>I]IGF-I binding with the following potencies (K<sub>I</sub>): IGF-I (0.74 n<i>M</i>) > IGF-II (3 n<i>M</i>) >> insulin (1 µ<i>M</i>). Affinity cross-linking with [<sup>125</sup>I]IGF-I using disuccinimidyl suberate and SDS-PAGE under reducing conditions yielded a polypeptide band with apparent M<sub>r</sub> 130,000, consistent with the α-subunit of the IGF-I receptor. IGF-I and IGF-II (0.3–30 n<i>M</i>) dose-dependently stimulated [<sup>3</sup>H]thymidine incorporation, with a maximal response of 110% above basal. IGF-II was approximately 10-fold less potent than IGF-I, suggesting a mediation through IGF-I receptors. In addition, the numbers of cells treated with 3 n<i>M</i> IGF-I amounted to 116, 130 and 159% of control values after 1, 2 and 4 days of incubation, respectively (p < 0.05). A significant increase in the cell CCK contents was observed after a 48-hour exposure to 3 or 30 n<i>M</i> IGF-I. These results demonstrate IGF-I receptor expression by the enteroendocrine cell line STC-1. IGF-I stimulates proliferation in short-term experiments, and increases intracellular levels of CCK.
Hypergonadotropic Hypogonadism in a 3-Year-Old Girl with Blepharophimosis, Ptosis, and Epicanthus inversus Syndrome
Authors: Ogata Tsutomu , Hasegawa Tomonobu , Tamai Shinya , Sato Seiji , Hasegawa Yukihiro , Matsuo Nobutake 
Published: April 2003

We report on ovarian dysfunction in a 3-year-old girl with blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES). A gonadotropin releasing hormone test showed hyperresponses of luteinizing hormone (<0.2→7.2 mIU/ml) and follicle-stimulating hormone (7.1→44.8 mIU/ml), and a human menopause gonadotropin test yielded no estradiol response (13→11 pg/ml). The results suggest that primary ovarian failure in type I BPES can take place in early childhood.
Central Precocious Puberty: A Single Blood Sample after Gonadotropin-Releasing Hormone Agonist Administration in Monitoring Treatment
Authors: Salerno Mariacarolina , Di Maio Salvatore , Gasparini Nicoletta , Mariano Angela , Macchia Vincenzo , Tenore Alfred 
Published: April 2003

This study was designed to evaluate whether a single blood sample drawn after the home injection of a long-acting gonadotropin-releasing hormone (GnRH) agonist (GnRHa) in patients treated for central precocious puberty (CPP) could be a more simple and inexpensive test with respect to the conventional GnRH stimulating test in assessing adequate suppression of the pituitary-gonadal axis. The response to the first therapeutic injection of the GnRHa triptorelin was studied in 14 newly diagnosed untreated females with CPP. The results were compared with the response that the same patients had to the conventional GnRH stimulation test performed at the time of diagnosis. A significant increase in LH, FSH and E<sub>2</sub> levels was observed 12 h after the triptorelin intramuscular injection; serum peak values of LH (70.3 ± 58.5 IU/l), FSH (44.2 ± 21.7 IU/l) and E<sub>2</sub> (489.7 ± 263.9 pmol/l) were significantly greater than those obtained with the conventional GnRH test (LH 31.4 ± 21.7, p = 0.002; FSH 19.8 ± 10.7, p = 0.001; E<sub>2</sub> 83.3 ± 25, p < 0.001). In particular, the E<sub>2</sub> response, 12 h after triptorelin injection, was clearly consistent with gonadal activation compared to the modest E<sub>2</sub> increase in response to the GnRH test. Thereafter 22 girls who were already being treated with triptorelin for CPP were evaluated to see whether a single blood sample drawn 12 h after the therapeutic home injection of GnRHa could be informative in assessing adequate suppression of the pituitary-gonadal axis. This response was also compared to the conventional GnRH stimulation test performed 2 days before the therapeutic triptorelin injection. In 7 girls with evidence of pubertal progression, the E<sub>2</sub> response following the GnRHa injection (136.3 ± 44.4 pmol/l) was significantly higher with respect to the response after the GnRH stimulation test (73.0 ± 0.0; p < 0.02) indicating an inadequate suppression of the pituitary-gonadal axis. The present data suggest that a single blood sample drawn 12 h after the therapeutic home administration of triptorelin provides a simple, comfortable and inexpensive means of monitoring pituitary as well as gonadal function in girls treated for CPP.
Mechanism of the Stimulatory Action of Antisteroid RU486 on Follicle-Stimulating Hormone Secretion in the Cyclic Rat
Authors: Sánchez-Criado J.E. , Tébar M. , Gonzalez D. 
Published: April 2003

These experiments explored the mechanism underlying FSH hypersecretion on estrous afternoon in rats injected with RU486 (RU) on proestrus. Four-day cyclic rats were injected with RU at 12:00 h on proestrus (1 or 4 mg/0.2 ml oil; s.c.), and its effects on LH and FSH secretion at 18:30 h on estrus were compared with those of antiprogestagens ZK299 (ZK) (1 or 4 mg/0.2 ml oil; s.c.) and Org31806 (OR) (2 or 8 mg/0.2 ml oil; s.c.). Additionally, rats treated with RU or nembutal (PB) (60 mg/kg; i.p. at 13:00 h on proestrus) were injected with an LHRH antagonist (LHRHa) at 10:00 h on estrus (1 mg/0.2 ml saline; s.c.) or progesterone (P) (7.7, 15.5 or 30.9 mg/0.2 ml oil; s.c.) on proestrus at 10:00 h in RU-injected rats and at 14:00 h in PB-injected rats. Animals were killed by decapitation at 18:30 h on estrus and serum LH and FSH concentrations were determined. Rats trated with 1 or 4 mg of RU or Org or 4 mg of ZK recorded increased serum FSH on estrous afternoon, while 1 mg ZK had no effect. PB increased mainly serum LH levels and, to a lesser extent, FSH levels. P decreased serum FSH concentrations in both RU- and PB-injected rats. LHRHa reversed the effects of PB on FSH secretions, but reduced FSH hypersecretion induced by RU only. These results are interpreted to mean that, in the absence of proestrous afternoon P-inhibitory action of the neural stimulus controlling LHRH release, FSH secretion on estrous afternoon involves two components: one is LHRH dependent while, in contrast to LH secretion, the other is LHRH independent, and only expressed in a low estrogen background.
Low-Dose Growth Hormone Treatment with Diet Restriction Accelerates Body Fat Loss, Exerts Anabolic Effect and Improves Growth Hormone Secretory Dysfunction in Obese Adults
Authors: Kim Kyung Rae , Nam Su Youn , Song Young Duk , Lim Sung Kil , Lee Hyun Chul , Huh Kap Bum 
Published: April 2003

Growth hormone (GH) can induce an accelerated lipolysis. Impaired secretion of GH in obesity results in the consequent loss of the lipolytic effect of GH. Dietary restriction as a basic treatment for obesity is complicated by poor compliance, protein catabolism, and slow rates or weight loss. GH has an anabolic effect by increasing insulin-like growth factor (IGF)-I. We investigated the effects of GH treatment and dietary restriction on lipolytic and anabolic actions, as well as the consequent changes in insulin and GH secretion in obesity. 24 obese subjects (22 women and 2 men; 22–46 years old) were fed a diet of 25 kcal/kg ideal body weight (IBW) with 1.2 g protein/kg IBW daily and were treated with recombinant human GH (n = 12, 0.18 U/kg IBW/week) or placebo (n = 12, vehicle injection) in a 12-week randomized, double-blind and placebo-controlled trial. GH treatment caused a 1.6-fold increase in the fraction of body weight lost as fat and a greater loss of visceral fat area than placebo treatment (35.3 vs. 28.5%, p < 0.05). In the placebo group, there was a loss in lean body mass (–2.62 ± 1.51 kg) and a negative nitrogen balance (–4.52 ± 3.51 g/day). By contrast, the GH group increased in lean body mass (1.13 ± 1.04 kg) and had a positive nitrogen balance (1.81 ± 2.06 g/day). GH injections caused a 1.6-fold increase in IGF-I, despite caloric restriction. GH response to <i>L</i>-dopa stimulation was blunted in all subjects and it was increased after treatment in both groups. GH treatment did not induce a further increase in insulin levels during an oral glucose tolerance test (OGTT) but significantly decreased free fatty acid (FFA) levels during OGTT. The decrease in FFA area under the curve during OGTT was positively correlated with visceral fat loss. This study demonstrates that in obese subjects given a hypocaloric diet, GH accelerates body fat loss, exerts anabolic effects and improves GH secretion. These findings suggest a possible therapeutic role of low-dose GH with caloric restriction for obesity.
Comparison between Low- and Standard-Dose ACTH Tests in Premature Infants at Risk for Chronic Lung Disease
Authors: Nykänen Päivi , Heinonen Kirsti , Voutilainen Raimo 
Published: April 2003

In order to find a sensitive method to evaluate adrenocortical function in premature infants, we compared low- (0.5 μg/1.73 m<sup>2</sup>) and standard-dose (250 μg/1.73 m<sup>2</sup>) adrenocorticotropin tests (LD- and SD-ACTH) in 12 very-low-birth-weight infants before and 2 days after the end of dexamethasone therapy (duration 9–14 days) for chronic lung disease. Basal serum cortisol levels were inappropriately low in several infants already before dexamethasone therapy (median 190, range 60–357 nmol/l). The 95% confidence intervals of mean serum cortisol levels at 20 min were equal in LD- and SD-ACTH, while at 60 min, the low-dose gave a clearly lower response than the standard-dose test. The LD-ACTH can be used in premature infants as in older children and adults, but the criteria for adrenocortical insufficiency need to be defined.
Expression of the Human Papillomavirus Type 11 E5A Protein from the E1∧E4,E5 Transcript
Authors: Brown Darron R. , McClowry Tracy L. , Sidner Richard A. , Fife Kenneth H. , Bryan Janine T. 
Published: April 2003

The abundant human papillomavirus type 11 (HPV 11) E1∧E4,E5 transcript potentially encodes the E1∧E4,E5a and E5b proteins. It is not known if either of the E5 proteins are expressed from this transcript. For HPV 16, E5 is a single open reading frame (ORF), and the E5 protein is expressed from an unspliced E2,E5 transcript but not from the spliced E1∧E4,E5 transcript. This study was undertaken to determine if the HPV 11 E5a protein is expressed from the E1∧E4,E5 transcript. To detect E5a expression in eukaryotic cells, the green fluorescent protein (GFP) gene was fused to the 3′ end of the E5a gene in the pEGFP-N1 vector. Several recombinant plasmid constructs were made to determine if E5a translation is influenced by upstream sequences present in the E1∧E4,E5 transcript. COS-7 cells were transfected with each construct, and flow cytometry was performed after 24 h of growth. The amount of E5a-GFP expressed from each construct was determined by the mean fluorescence of 2,000 transfected cells. Although the E5a-GFP fusion was expressed by all but one construct, the quantity of expressed E5a-GFP varied considerably. The most abundant expression was detected in cells transfected with the E1∧E4,E5a construct that lacked the 5′ noncoding sequence between nucleotides (nts) 714 and 831 that is present in the authentic transcript. Other constructs expressed E5a-GFP in variable amounts, suggesting that sequences between nt 714 and the start of the E5a ORF affect expression of the E5a protein. An E2,E5a construct was made to compare the HPV 11 E5a expression to that of HPV 16. In contrast to HPV 16, no E5a-GFP was expressed from the HPV 11 E2,E5a construct. E1∧E4 protein was detected by immunofluorescence in COS-7 cells transfected with a construct that expressed E1∧E4 as a T7-epitope-tagged protein, and E5a as a GFP fusion. We conclude that the abundant HPV 11 E1∧E4,E5 transcript is a functional message that can support both E1∧E4 and E5a expression in eukaryotic cells.
Coinfection of <i>Spodoptera exigua</i> and <i>Spodoptera frugiperda</i> Cell Lines with the Nuclear Polyhedrosis Viruses of <i>Autographa californica</i> and<i>Spodoptera exigua</i>
Authors: Yanase Tohru , Yasunaga Chisa , Hara Toshio , Kawarabata Takeshi 
Published: April 2003

The <i>Autographa californica</i> multinucleocapsid nuclear polyhedrosis virus (AcMNPV) has a broad host range among Lepidoptera. In contrast, the <i>Spodoptera exigua</i> MNPV (SeMNPV) can replicate efficiently only in <i>S. exigua</i> larvae or <i>S. exigua</i>-derived cell lines. In this study, we examined the coinfection of <i>S. exigua</i> Se301 and <i>Spodoptera frugiperda</i> IPLB-SF21AEII (Sf21) cell lines with SeMNPV and AcMNPV recombinant (Ac360-<i>501β-gal</i>) which was constructed for expression of β-galactosidase under control of the polyhedrin promoter. Coinfection led to the restriction as the level of late gene expression, nonoccluded virus production, and DNA replication of Ac360-<i>501β-gal</i> in both Se301 and Sf21 cell lines. In contrast, Ac360-<i>501β-gal</i> supported the SeMNPV replication in Sf21 cells. Occurrence of recombinants, between Ac360-<i>501β-gal</i> and SeMNPV, with expanded host range was not observed in coinfected Sf21 cells. This suggests that Ac360-<i>501β-gal</i> supports the SeMNPV replication through <i>trans</i>-activation.
Close Association between High Serum ALT and More Rapid Recurrence of Hepatocellular Carcinoma in Hepatectomized Patients with HCV-Associated Liver Cirrhosis and Hepatocellular Carcinoma
Authors: Tarao Kazuo , Rino Yasushi , Takemiya Shoji , Tamai Setsuo , Ohkawa Shinichi , Sugimasa Yukio , Miyakawa Kaoru , Morinaga Soichiro , Yoshida Muneki , Shibuya Akitaka , Kokubu Shigehiro , Kakita Akira , Endo Osamu 
Published: April 2003

We investigated whether or not a high serum alanine aminotransferase (ALT) level is associated with a more rapid recurrence of hepatocellular carcinoma (HCC) in hepatectomized patients with hepatitis C virus (HCV)-associated liver cirrhosis (LC) (HCV-LC) and HCC. Thirty-three hepatectomized patients with HCV-LC and HCC of a single nodule who had no histologic evidence of portal or hepatic vein invasion and who had been followed up for more than 3 years were included in the study. They were subdivided into two groups according to their serum ALT levels, ALT being a well-known marker of inflammatory necrosis in the liver. Seventeen patients whose serum ALT levels showed several peaks or plateaus above 80 international units (IU) were designated as the high ALT group, and 16 patients whose serum ALT levels showed a sustained low level below 80 IU until the first recurrence were designated as the low ALT group, and the interval between hepatectomy and the first recurrence was observed. In the high ALT group, HCC recurred within 3 years in 70.6% of the patients. In contrast, it recurred in only 18.8% of the low ALT group within the same period (p < 0.05). There was a significant difference (p = 0.0201) between the two groups in the cumulative nonrecurrence rate. The mean interval in recurrent patients between hepatectomy and the first recurrence in the high ALT group (23.6 ± 2.8 months; mean ± SE) was significantly (p < 0.02) shorter than that in the low ALT group (49.3 ± 9.7 months). The expected interval between hepatectomy and recurrence was as short as 2.8 ± 0.5 years (mean ± SE) in the high ALT group, compared with 5.8 ± 0.7 years in the low ALT group (p < 0.05). These results showed that the recurrence of HCC was accelerated in the high ALT group, suggesting that suppression of the rise in ALT level after hepatectomy by treatment with anti-inflammatory drugs may prolong the interval until recurrence by about 2 years in hepatectomized patients with HCC and HCV-LC.
Contribution of Individual Structural Components in Determining the Zero-Stress State in Small Arteries
Authors: Zeller Peter J. , Skalak Thomas C. 
Published: April 2003

Arterial-wall stress distributions are important determinants of arterial function and are determined by the mechanical properties of the vessel wall, the physiological loading conditions, and the zero stress state of the artery. In this study, the relationship between this zero-stress state, the contractile state of the vessel, and the extracellular matrix components was investigated. Rat saphenous arteries were excised, and cross-sectional slices were cut. Wall thickness, intimal circumference, medial to adventitial border circumference, and the outer adventitial circumference were measured. Each slice was cut once longitudinally to relieve the residual stresses, and after a period of 30 min, vessel dimensions were again measured, and the angle to which the arterial section opened, a measure of the residual stress present in the intact artery, was recorded in this new zero-stress state. Control ‘opening angle’ was 112 ± 10° (mean ± SD, n = 8) as compared to 138 ± 6° (n = 18) and 127 ± 6° (n = 11) for slices placed in 10<sup>–4</sup> <i>M</i> adenosine at 25 and 37°C, respectively. Fluorescein isothiocyanate dextran was also injected intravenously in 8 animals to measure the homeostatic lumen diameter and wall thickness using intravital microscopy. Comparison of homeostatic strains calculated from these in situ dimensions to residual strains indicated that a given opening angle produced a radially uniform circumferential strain only for a specific level of tone. These results suggest that smooth muscle tone can acutely modify residual strain, possibly through interconnections with matrix components. Furthermore, selective elimination of matrix components by post-treatment of zero-stress slices with elastase or collagenase in 6 animals each increased the opening angle by 53 and 70%, respectively, suggesting that the extracellular matrix structure may regulate arterial strains in the long term.
Role of Intracellular Calcium for Noradrenaline-Induced Depolarization in Rat Mesenteric Small Arteries
Authors: Nilsson Holger , Videbæk Lars M. , Toma Catalin , Mulvany Michael J. 
Published: April 2003

We have investigated the effect of intracellular calcium levels for membrane potential during noradrenaline application in isolated small arteries. Rat mesenteric small arteries were mounted for isometric tension measurement. Smooth muscle membrane potentials were measured by conventional intracellular electrodes, and intracellular calcium concentration was measured using Fura-2 fluorescence. Under control conditions, noradrenaline caused contraction and depolarization from –55.5 to –29.3 mV. In intact arteries, depleting intracellular calcium stores with thapsigargin caused smooth muscle hyperpolarization and inhibited contraction to noradrenaline. In de-endothelialized vessels, thapsigargin still depleted calcium stores, but did not affect either the depolarization or contraction caused by noradrenaline. In noradrenaline-activated vessels, inhibition of calcium influx by amlodipine caused tension and calcium levels to fall to near-baseline levels, but membrane potential returned by only 55%. Treatment with a combination of thapsigargin, D-600 and BAPTA-AM inhibited the tension and calcium responses to noradrenaline, but the membrane potential response was reduced by only 34%. Acute reduction of extracellular chloride concentration caused similar, small depolarization at rest and during noradrenaline exposure. It is concluded that an elevation of intracellular calcium concentration is not essential for noradrenaline depolarization, although part of the depolarization is associated with the raised intracellular calcium level.
Segmental Differences in Geometric, Elastic and Contractile Characteristics of Small Intramural Coronary Arteries of the Rat
Authors: Szekeres Mária , Nádasy György L. , Dézsi László , Orosz Miklós , Tökés Annamária , Monos Emil 
Published: April 2003

The depedence of elastic and contractile properties on the caliber of small intramural coronary arteries was investigated in the rat in vitro. Different segments of the left anterior descending coronary artery branching system were prepared for microarteriography. The segments were cannulated at both ends, immersed in oxygenated normal Krebs Ringer (nKR) solution. Intraluminal pressure was changed at a rate of about 0.5 mm Hg/s between 0 and 150 mm Hg in repeated cycles. The outer diameter was continuously measured with microangiometry. Pressure-diameter curves were recorded after preconditioning pressure cycles in nKR, with PGF<sub>2α</sub> in the bath (7.5 × 10<sup>–6</sup> <i>M</i>), and in maximal relaxation with papaverine (2.8 × 10<sup>–4</sup> <i>M</i>). Biomechanical parameters were computed for vessels grouped according to their calibers (inner diameters: 50–150, 150–250, 250–350, >350 µm). Distensibility and contractility decreased with increasing caliber of the vessels, while the elastic modulus increased. Spontaneous tone was (at 100 mm Hg in mechanically preconditioned vessels) 18.8 ± 4.5, 8.4 ± 4.4, 9.7 ± 3.7 and 8.3 ± 3.8% in the four groups, respectively. PGF<sub>2α</sub> contraction was maximal around the 300-µm caliber. Our study is the first direct demonstration that intramural small coronary arteries exhibit characteristic variability in their elastic and contractile properties as a function of their caliber. Such differences may be important in segmentally specific control processes of the coronary microcirculation.
Barium and 4-Aminopyridine Inhibit Flow-Initiated Endothelium-Independent Relaxation
Authors: Xie Hui , Bevan John A. 
Published: April 2003

Although much is known about the underlying mechanism of endothelium-dependent flow-induced vasorelaxation, the cellular processes responsible for the endothelium-independent flow-induced relaxation observed in some vessels is unknown. As there is evidence for the participation of K<sup>+</sup> channels in the endothelium-dependent response, the present study was designed to determine whether such channels are involved in the endothelium-independent response and if so, which ones. We examined the effects of various selective K<sup>+</sup> channel blockers on endothelium-independent relaxation initiated by intraluminal flow (10–80 µl/min), and by an endothelium-independent vasodilator sodium nitroprusside (SNP, 1 nmol/l to 3 µmol/l) in segments of the rabbit facial vein under isometric conditions. Flow-initiated relaxation was abolished by 25 and 40 mmol/l K<sup>+</sup> as well as 10 mmol/l tetraethylammonium (TEA), significantly inhibited by 100 µmol/l Ba<sup>2+</sup>, 5 mmol/l Cs<sup>+</sup> and 7.5 mmol/l 4-aminopyridine (4-AP), but unaffected by 5 µmol/l glibenclamide and 50 nmol/l charybdotoxin. Relaxation induced by SNP was reduced by 7.5 mmol/l 4-AP, but not by any of the above drugs in their listed concentrations. The inhibitory effect of 100 µmol/l Ba<sup>2+</sup> on the relaxation caused by low concentrations of K<sup>+</sup> (15–20 mmol/l) supports the presence of inward rectifier K<sup>+</sup> channels in the vascular smooth muscle cells of this tissue. We speculate that endothelium-independent flow-initiated relaxation of the rabbit facial vein may be associated with activation of inward rectifier and voltage-dependent K<sup>+</sup> channels. The latter may also contribute to the vasorelaxation initiated by SNP.