bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endogenous Sex Hormones and Cardiovascular Disease in Men
Authors: Muller Majon , van der Schouw Yvonne T. , Thijssen Jos H. H. , Grobbee Diederick E. 
Published: November 2003

AbstractUnlike women, men do not experience an abrupt reduction in endogenous sex hormone production. It has, however, become clear that an age-associated decrease in the levels of (bioactive) sex hormones does occur. Whether endogenous sex hormones have an impact on cardiovascular disease has for many years remained largely unknown, but during the last decade more attention has been drawn to the importance of testosterone, estrogens, and adrenal androgens in etiology, prevention, and treatment of male cardiovascular disease. The purpose of this article is to summarize the evidence currently available on the association between endogenous sex hormones and cardiovascular disease in males. Published studies dealing with the relationship between circulating levels of sex hormones and cardiovascular disease in males were reviewed. The studies reviewed in this article suggest that circulating endogenous sex hormones and estrogens have a neutral or beneficial effect on cardiovascular disease in men.
Effects of Growth Hormone (GH) on Ghrelin, Leptin, and Adiponectin in GH-Deficient Patients
Authors: Engström Britt Edén , Burman Pia , Holdstock Camilla , Karlsson F. Anders 
Published: November 2003

Abstract
Ghrelin is a recently discovered gastric peptide that increases appetite, glucose oxidation, and lipogenesis and stimulates the secretion of GH. In contrast to ghrelin, GH promotes lipolysis, glucose production, and insulin secretion. Both ghrelin and GH are suppressed by intake of nutrients, especially glucose. The role of GH in the regulation of ghrelin has not yet been established.
We investigated the effect of GH on circulating levels of ghrelin in relation to its effects on glucose, insulin, body composition, and the adipocyte-derived peptides leptin and adiponectin. Thirty-six patients with adult-onset GH deficiency received recombinant human GH for 9 months in a placebo-controlled study. Body composition and fasting serum analytes were assessed at baseline and at the end of the study. The GH treatment was accompanied by increased serum levels of IGF-I, reduced body weight (−2%) and body fat (−27%), and increased serum concentrations of glucose (+10%) and insulin (+48%). Ghrelin levels decreased in 30 of 36 subjects by a mean of −29%, and leptin decreased by a mean of −24%. Adiponectin increased in the women only. The decreases in ghrelin and leptin correlated with changes in fat mass, fat-free mass, and IGF-I. The reductions in ghrelin were predicted independently of the changes in IGF-I and fat mass.
It is likely that the reductions in ghrelin and leptin reflect the metabolic effects of GH on lipid mobilization and glucose production. Possibly, a suppression of ghrelin promotes loss of body fat in GH-deficient patients receiving treatment. The observed correlation between the changes in ghrelin and IGF-I may suggest that the GH/IGF-I axis has a negative feedback on ghrelin secretion.
Longitudinal Association between Sex Hormone Levels, Bone Loss, and Bone Turnover in Elderly Men
Authors: Gennari Luigi , Merlotti Daniela , Martini Giuseppe , Gonnelli Stefano , Franci Beatrice , Campagna Stella , Lucani Barbara , Dal Canto Norberto , Valenti Roberto , Gennari Carlo , Nuti Ranuccio 
Published: November 2003

Abstract
Male osteoporosis is an increasingly important health problem. It is known that sex steroid hormones play an important role in regulating bone turnover and bone mass in males as well as in females. However, the exact mechanism of bone loss in men remains unknown. In the present study, 200 elderly men (age range, 55–85 yr) were followed for 4 yr to evaluate the relationships between hormone levels, bone turnover markers, bone mineral density, and rates of bone loss. Femoral and lumbar bone mineral density, bone ultrasound parameters at the os calcis, serum testosterone (T), serum estradiol (E2), SHBG levels, and bone turnover markers (urinary crosslaps and bone alkaline phosphatase) were evaluated for each man at enrollment and 4 yr afterward. The free androgen index (FAI) and free estrogen index (FEI) as well as measures of the bioavailable sex hormones [calculated bioavailable E2 (c-bioE2) and T (c-bioT)] were calculated from total hormone levels and SHBG. In the total population, T, c-bioT, c-bioE2, FAI, and FEI, but not E2, decreased significantly with age, whereas SHBG increased significantly. Subjects with FEI, c-bioE2, and E2 levels below the median showed higher rates of bone loss at the lumbar spine and the femoral neck as well as higher speed-of-sounds decrease at the calcaneus with respect to men with FEI, c-bioE2, and E2 levels above the median. Serum bone alkaline phosphatase and urinary crosslaps were significantly higher in men with FEI, c-bioE2, and E2 in the lower quartile than in men with FEI, c-bioE2, and E2 levels in the higher quartile. No statistically significant differences were observed in relation to T, c-bioT, or FAI levels. Finally, the ratio between E2 and T, an indirect measure for aromatase activity, increased significantly with age and was higher in normal than in osteoporotic subjects. In conclusion, results from the present study indicate an important role of estrogens, and particularly of the ability to aromatize T to E2, in the regulation of bone loss and bone metabolism in elderly men.
Familial Hypocalciuric Hypercalcemia in a Woman with Metastatic Breast Cancer: A Case Report of Mistaken Identity
Authors: Marcocci Claudio , Borsari Simona , Pardi Elena , Dipollina Giada , Giacomelli Tamara , Pinchera Aldo , Cetani Filomena 
Published: November 2003

Abstract
We describe a 45-yr-old woman with metastatic breast cancer and hypercalcemia previously diagnosed as hypercalcemia of malignancy and treated with bisphosphonates without changes of serum calcium (s-Ca). At the time of our evaluation, biochemical data [s-Ca, 10.8 mg/dl (2.70 mmol/liter); PTH, 24.4 pg/ml (2.6 pmol/liter); 24-h urinary calcium, 160 mg (4.0 mmol); calcium/creatinine clearance, 0.007] suggested the diagnosis of familial hypocalciuric hypercalcemia. Three of five relatives had mild hypercalcemia [s-Ca, 10.7–11.2 mg/dl (2.67–2.80 mmol/liter)] and detectable serum PTH [24.5–29.0 pg/ml (2.6–3.1 pmol/liter)]. A novel heterozygous I212T missense mutation in exon 4 of the calcium-sensing receptor (CaR) gene was found in the proband and affected relatives but not in unaffected relatives. Expression of the mutant I212T CaR in COS-7 cells resulted in no response of inositol phosphates to any calcium concentration. The calcium dose-response curve of the coexpressed receptors [wild-type/I212T] suggested that the mutant receptor interferes with the function of the wild-type receptor. In conclusion, we describe a case of familial hypocalciuric hypercalcemia due to a novel CaR mutation, in a woman with breast cancer in whom hypercalcemia was initially attributed to hypercalcemia of malignancy.
Efficacy and Safety of Human Parathyroid Hormone-(1–84) in Increasing Bone Mineral Density in Postmenopausal Osteoporosis
Authors: Hodsman Anthony B. , Hanley David A. , Ettinger Mark P. , Bolognese Michael A. , Fox John , Metcalfe Anna J. , Lindsay Robert 
Published: November 2003

Abstract
Daily sc injections of N-terminal analogs of PTH increase bone mass and decrease fractures in osteoporotic women. We investigated the efficacy and safety of human PTH-(1–84) (full-length PTH) in the treatment of postmenopausal osteoporosis in a double-blind, placebo-controlled study. The women (n = 50–53/group) self-administered PTH (50, 75, or 100 μg) or placebo by daily sc injection for 12 months. PTH treatment induced time- and dose-related increases in lumbar spine bone mineral density (BMD). The 100-μg dose increased BMD significantly at 3 months (+2.0%) and 12 months (+7.8%). BMD underestimated the anabolic effect of PTH in lumbar spine (bone mineral content, +10.0%) because bone area increased significantly (+2.0%). A nonsignificant decrease (−0.9%) in total hip BMD occurred during the first 6 months with the 100-μg dose, but this trend reversed (+1.6%) during the second 6 months. Bone turnover markers increased during the first half of the study and were maintained at elevated levels during the second 6 months. Protocol compliance was excellent (95–98%), and treatment was generally safe and well tolerated. Dose-related incidences of transient hypercalcemia occurred, but only one patient (100-μg group) was withdrawn because of repeated hypercalcemia. Thus, full-length PTH was efficacious and safe over 12 months.
Characterization of Endozepines in the Human Testicular Tissue: Effect of Triakontatetraneuropeptide on Testosterone Secretion
Authors: Duparc Celine , Lefebvre Herve , Tonon Marie-Christine , Vaudry Hubert , Kuhn Jean-Marc 
Published: November 2003

AbstractPrevious studies have shown that endozepines, i.e. endogenous ligands of benzodiazepine (BZD) receptors, stimulate steroidogenesis in adrenocortical and Leydig cells. In the present report, we have investigated the presence and action of endozepines in the human testis. Immunohistochemical labeling revealed the occurrence of endozepine-like immunoreactivity in Leydig, Sertoli, and germ cells. HPLC analysis combined with a specific RIA resolved two immunoreactive peaks that coeluted with synthetic octadecaneuropeptide (ODN) and triakontatetraneuropeptide (TTN). RT-PCR amplification showed that the mRNA encoding the endozepine precursor diazepam-binding inhibitor is expressed in the human testis. The action of endozepines on testosterone production was studied in vitro using perifused human testicular fragments. Administration of TTN provoked a dose-dependent increase in testosterone secretion, whereas ODN had no effect. The stimulatory action of TTN on testosterone production was totally blocked by flunitrazepam, a peripheral-type BZD receptor antagonist/central-type BZD receptor (CBR) agonist. Conversely, the CBR agonist clonazepam and the CBR antagonist flumazenil did not affect testosterone secretion. Collectively, these results suggest that, in the human testicular tissue, TTN may exert an intracrine and/or paracrine control of steroidogenesis through activation of a peripheral-type BZD receptor.
Differential Responses of Circulating Ghrelin to High-Fat or High-Carbohydrate Meal in Healthy Women
Authors: Monteleone Palmiero , Bencivenga Rachele , Longobardi Nicola , Serritella Cristina , Maj Mario 
Published: November 2003

Abstract
The effects of specific nutritional factors on ghrelin secretion have not been investigated in humans. Therefore, we assessed ghrelin responses to a high-carbohydrate meal (1217 kcal with 77% carbohydrates, 10% protein, and 13% lipids) and to an isocaloric high-fat meal (15% carbohydrates, 10% proteins, and 75% lipids) in 14 nonobese healthy women. Eleven subjects also rated their hunger feelings on visual analog scales. Circulating ghrelin abruptly fell after both meals, but, after the carbohydrate meal, its maximum percent decrease was significantly greater than after the fat meal (P = 0.02). Plasma insulin and glucose levels rose after the meals, but their increases were significantly higher after the carbohydrate meal than after the fat meal. No significant change was observed in circulating leptin after both meals. Moreover, compared with the fat meal, the carbohydrate meal had a significantly greater suppressant effect on hunger feelings. Plasma ghrelin changes were significantly associated with hunger changes (P &lt; 0.007). These findings show that circulating ghrelin is differently suppressed by diet manipulations. The mechanisms responsible for such a phenomenon and its possible implication in the physiology of human satiety remain to be elucidated.
Increased Luteinizing Hormone Secretion in Women with Polycystic Ovary Syndrome Is Unaltered by Prolonged Insulin Infusion
Authors: Patel Ketan , Coffler Mickey S. , Dahan Michael H. , Yoo Richard Y. , Lawson Mark A. , Malcom Pamela J. , Chang R. Jeffrey 
Published: November 2003

Abstract
In PCOS women with insulin resistance, hyperinsulinemia may contribute to inappropriate gonadotropin secretion. To determine whether insulin influences gonadotropin release in PCOS, pulsatile LH secretion and gonadotropin responses to GnRH were evaluated before (phase 1) and during (phase 2) insulin infusion. In phase 1, 11 PCOS and 9 normal women on separate days underwent 1) frequent blood sampling (q 10 min) for 12 h and 2) gonadotropin stimulation by successive doses of GnRH, 2 μg, 10 μg, and 20 μg, administered iv at 4 h intervals over a continuous 12 h. In phase 2, studies were repeated 2 h after initiation of a 12-h hyperinsulinemic-euglycemic clamp (80 mU/m2·min). Administration of insulin to both groups failed to alter mean serum gonadotropin concentrations, LH pulse frequency, or LH pulse amplitude. Moreover, gonadotropin responses to GnRH were unchanged by insulin infusion. In PCOS and normal women, a significant reduction of serum androstenedione was associated with insulin administration, whereas no differences were noted for the remaining androgens and estrogens measured.
These findings demonstrated that in PCOS women, LH secretion and gonadotropin responses to GnRH were not influenced by insulin administration. Insulin infusion had little effect on steroid hormone production with the possible exception of androstenedione. These results suggest that inappropriate LH secretion in PCOS is not a direct consequence of insulin resistance and compensatory hyperinsulinemia.
Phenotypic Heterogeneity in Body Fat Distribution in Patients with Congenital Generalized Lipodystrophy Caused by Mutations in the AGPAT2 or Seipin Genes
Authors: Simha Vinaya , Garg Abhimanyu 
Published: November 2003

Abstract
Congenital generalized lipodystrophy (CGL) is a rare autosomal recessive syndrome characterized by extreme paucity of adipose tissue since birth, acanthosis nigricans, severe insulin resistance, marked hypertriglyceridemia, and early-onset diabetes mellitus. Recently, we reported mutations in the 1-acylglycerol-3-phosphate O-acyltransferase 2 (AGPAT2) gene in CGL pedigrees linked to chromosome 9q34 (CGL1 subtype), and mutations in the Seipin gene were reported in pedigrees linked to chromosome 11q13 (CGL2 subtype). Whether the two subtypes have differences in body fat distribution has not been investigated. We, therefore, compared whole-body adipose tissue distribution by magnetic resonance imaging in 10 CGL patients, of whom seven (six females, one male) had CGL1 and three (two males, one female) had CGL2. Both subtypes had marked lack of metabolically active adipose tissue located at most sc, intermuscular, bone marrow, intraabdominal, and intrathoracic regions. Paucity of mechanical adipose tissue in the palms, soles, orbits, scalp, and periarticular regions was noted in CGL2, whereas it was well preserved in CGL1 patients. We conclude that CGL patients with Seipin mutations have a more severe lack of body fat, which affects both metabolically active and mechanical adipose tissue, compared with patients with mutations in the AGPAT2 gene.
Functional, Structural, and Distribution Analysis of the Chorionic Gonadotropin Receptor Using Murine Monoclonal Antibodies
Authors: Funaro Ada , Sapino Anna , Ferranti Bruna , Horenstein Alberto L. , Castellano Isabella , Bagni Bruno , Garotta Gianni , Malavasi Fabio 
Published: November 2003

AbstractLH and human chorionic gonadotropin (hCG) control steroid production and gametogenesis. They also function as growth factors through interaction with a specific receptor that is a member of the seven-transmembrane receptor family coupled via G proteins to signal pathways involving cAMP and phospholipase C/inositol 3 phosphate.For this study, monoclonal antibodies (mAbs) were raised against the human LH receptor (LHR)/hCG receptor (hCGR), using Chinese hamster ovary LHR-transfected cells as the immunogen. Two reagents were then selected on the basis of their ability to recognize the full-length transmembrane re-ceptor expressed both by Chinese hamster ovary LHR-transfected cells and by a limited number of tumor cell lines.One of these mAbs reacts with the LHR/hCGR in tissue sections of both frozen and paraffin-embedded specimens. This unique feature allowed us to map the cytological distribution of LHR/hCGR in human breast tissues at different stages of development in physiological and benign pathological conditions. The same mAb proved to be agonistic: receptor ligation elicits signals that modulate the growth of selected breast tumor cell lines. This observation suggests that the mAb recognizes an epitope that is included in the domain of the receptor involved in the interaction with the natural ligand.
Marketing Literature Review
Authors: Leonard Myron 
Published: November 2003

This section is based on a selection of article abstracts from a comprehensive business literature database. Marketing-related abstracts from more than 125 journals (both academic and trade) are reviewed by JM staff. Descriptors for each entry are assigned by JM staff. Each issue of this section represents three months of entries into the database. Each entry has an identifying number. Cross-references appear immediately under each subject heading. The following article abstracts are available online from the ABI/INFORM database, which is published and copyrighted by Bell & Howell Information and Learning. For additional information about access to the database or about obtaining photocopies of the articles abstracted here, please call (800) 521-0600 or write to B&H, 300 N. Zeeb Rd., Ann Arbor, MI 48106.
Air and Ship‐Based Space Launch Vehicles
Authors: Fenn Dale 
Published: October 2003

Abstract
In 1957, the Soviet Union placed the first man‐made object in orbit around the earth. Since then, numerous launch vehicles have been developed to improve the performance, reliability, and cost of placing objects in orbit. By one estimate, roughly 75 active space launch vehicles either have established flight records or are planning an inaugural launch within the year. This does not include the numerous launch vehicles from around the world that are no longer operational such as the Jupiter, Redstone, Juno, Saturn, Scout, Thor, Vanguard, and Conestoga family of rockets from the United States or the N‐1 from the former Soviet Union, to name just a few. Despite the many differences among all of these launch vehicles from both past and present, one common element can be found in all but four of them: they are ground‐launched. Of the four exceptions, two are air‐launched (NOTSNIK and Pegasus), one is ship‐launched (Sea Launch), and one is submarine‐launched (Shtil). It is important to keep in mind that numerous air‐launched and ship‐launched suborbital launch systems are in use by militaries, commercial entities, and educational institutions. However, the four mentioned are the only mobile launch systems that can place objects into a sustainable Earth orbit. The launch systems and the advantages and disadvantages of these systems are discussed.
Moon
Authors: Spudis Paul D. 
Published: October 2003

Abstract
The Moon, the natural satellite of Earth, has positively affected our development in many profound ways. Its orbital presence helps stabilize Earth's axial precession and thus, prevents the alternating extremes of climate that some planets, such as Mars, experience. This equitable climate makes Earth a habitable world. The ocean tides induced by the Moon probably permitted vertebrate life to emerge from the sea more than 300 million years ago, leading to the development of land fauna and ultimately, to ourselves. Thus in a very real sense, we are here because the Moon exists.
Now, the Moon is exerting its beneficial influence on us once again by its existence. The Moon is the first milepost in humanity's movement into the solar system. We must pass by the Moon's orbit to go anywhere else in space. Thus, nature has provided us with a natural “way station,” a place to learn how to live and work in space, refuel, and refresh our spacecraft. In addition to these benefits, the Moon also happens to be a rather interesting place. Its surface contains a record of the important events that occurred in the early history of Earth. Moreover, it is an excellent platform to observe the Universe around us. In all of these ways, the Moon is an important part of our movement into space. Basic properties and motions of the moon are given as well as its origin and structure.
Scientific data from the Apollo and post Apollo missions are discussed. Later missions are designed to look for water on the moon water could help support a lunar colony on the moon as an outpost for exploration.
NASA
Mission Operation Control Center at Johnson Space Center
Authors: Lunney Glynn S. 
Published: October 2003

Abstract
As the Space Task Group (STG) began to relocate to Houston, Texas, from Langley Field, Virginia, in 1962, the last of the Mercury flights were still being supported from the Mercury Control Center (MCC) at the Cape Canaveral Air Force Station in Florida. In those early days, dramatic change was underway throughout the manned space program. Galvanized by President Kennedy's Moon challenge in 1961, Gemini and Apollo began to take form in the engineering, design, and manufacturing organizations throughout the country. The learning curves were very steep in all of the disciplines. This was equally true in the control of flight operations, as they were facilitated in the first control center in Florida and at key remote sites around the globe.
The flight operations function (becoming known as flight control) faced new changes for the upcoming programs—missions were much more complex due to rendezvous, extra vehicular activity (EVA), and lunar challenges. Telemetry and command systems were changing from analog to digital, reliable global communications were enabling a more centralized control center with fewer remote sites, and the schedule demanded extensive training with concurrent training for one flight while actively performing another simultaneously. All of these considerations and others led to the conclusion that the new Mission Control Center must be colocated with the flight control team in Houston.
This article details the various missions launched from Houston basic concepts of flight control are discussed. Missions in the Gemini, Apollo, Skylab, Apollo‐Soyuz, Space Shuttle, and Challenger programs are discussed. Space station preparations are considered.