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71.
OBJECTIVE: Adiponectin is an adipocyte-specific secretory protein which exhibits antiatherogenic, anti-inflammatory and antidiabetic properties. We hypothesized that testosterone plays an important role in the regulation of its secretion in humans, as adiponectin concentrations are higher in women than in men and as testosterone administration is accompanied by a reduction in serum adiponectin in animals and by reduced protein secretion in cultured adipocytes. This study aimed to evaluate adiponectin levels in hypogonadal men prior to and during testosterone replacement therapy. SUBJECTS AND METHODS: In a retrospective study, adiponectin, total and free testosterone, oestradiol, SHBG, total cholesterol and triglyceride levels were evaluated in 31 hypogonadal men [HM; age, mean +/- SEM: 36.5 +/- 2.4 years; body mass index (BMI) 24.6 +/- 0.8 kg/m2] and 29 weight-matched eugonadal men (EM; age 30.8 +/- 1.5 years; BMI 23.4 +/- 0.6 kg/m2). In 13 HM (age 33.9 +/- 3.2 years; BMI 24.2 +/- 0.9 kg/m2) the same parameters were also evaluated after 6 months of testosterone replacement therapy. Correlation analysis between adiponectin and hormonal, biochemical and anthropometric parameters was performed in all subjects. RESULTS: Testosterone, free testosterone and oestradiol concentrations were significantly lower in HM than in EM (4.4 +/- 0.4 nmol/l, 78.4 +/- 10.9 pmol/l and 36.1 +/- 3.0 pmol/l, respectively, in HM vs. 21.9 +/- 0.7 nmol/l, 507.9 +/- 13.8 pmol/l and 65.2 +/- 1.8 pmol/l, respectively, in EM, P < 0.0001), while SHBG levels in HM were higher than in EM (54.4 +/- 7.5 vs. 30.9 +/- 2.2 nmol/l, P < 0.005). Serum adiponectin levels in HM were significantly higher than in EM (9.53 +/- 0.73 vs. 6.80 +/- 0.55 microg/ml, P < 0.01). Calculation of the Pearson coefficient showed that adiponectin levels in HM were not correlated with any of the anthropometric and hormonal parameters examined, but showed a significant negative correlation with serum triglycerides (r = -0.38, P < 0.05). Serum adiponectin levels were negatively correlated with body weight (r = -0.41, P < 0.05) in EM but not with other anthropometric, hormonal or biochemical parameters. Six months after initiation of testosterone replacement therapy, which increased testosterone and free testosterone levels to the normal range, adiponectin levels were significantly reduced in HM (6.37 +/- 0.93 vs. 9.26 +/- 1.01 microg/ml, P < 0.01) and similar to those recorded in EM. CONCLUSIONS: Compared to eugonadal subjects, hypogonadal men show higher adiponectin levels which are reduced by testosterone replacement therapy. This study indicates that testosterone exerts a regulatory role on adiponectin secretion in humans. 相似文献
72.
von Eckardstein S Noe G Brache V Nieschlag E Croxatto H Alvarez F Moo-Young A Sivin I Kumar N Small M Sundaram K;International Committee for Contraception Research The Population Council 《The Journal of clinical endocrinology and metabolism》2003,88(11):5232-5239
Several preparations of testosterone and its esters are being investigated alone or in combination with other gonadotropin-suppressing agents as possible antifertility agents for men. We studied the effectiveness of 7 alpha-methyl-19-nortestosterone (MENT) as an antispermatogenic agent in men. MENT has been shown to be more potent than testosterone and to be resistant to 5 alpha-reduction. For sustained delivery of MENT, we used a system consisting of ethylene vinyl acetate implants containing MENT acetate (Ac), administered subdermally. Thirty-five normal volunteers were recruited in 3 clinics and were randomly assigned to 1 of 3 doses: 1 (12 men), 2 (11 men), or 4 (12 men) MENT Ac implants. The initial average in vitro release rate of MENT Ac from each implant was approximately 400 micro g/day. Implants were inserted subdermally in the medial aspect of the upper arm under local anesthesia. The duration of treatment was initially designed to be 6 months. However, in 2 clinics the duration of treatment was extended to 9 months for the 2-implant group and to 12 months for the 4-implant group. Dose-related increases in serum MENT levels and decreases in testosterone, LH, and FSH levels were observed. Effects on sperm counts were also dose related. None of the subjects in the 1-implant group exhibited oligozoospermia (sperm count, <3 million/ml). Four subjects in the 2-implant group became oligozoospermic, 2 of whom reached azoospermia. Eight subjects in the 4-implant group reached azoospermia, with 1 exhibiting oligozoospermia, whereas 2 were nonresponders. Side effects generally seen with androgen administration, such as increases in erythrocyte count, hematocrit, and hemoglobin and a decrease in SHBG, were also seen in this study and were reversible. Changes in lipid parameters were moderate and transient. Liver enzymes showed small changes. This study demonstrates that MENT Ac, when administered in a sustained release fashion via subdermal implants, can inhibit spermatogenesis over a prolonged period after a single administration and has the potential to be used as a male contraceptive. 相似文献
73.
Role of sequence variations of the GnRH receptor and G protein-coupled receptor 54 gene in male idiopathic hypogonadotropic hypogonadism 总被引:6,自引:0,他引:6
Lanfranco F Gromoll J von Eckardstein S Herding EM Nieschlag E Simoni M 《European journal of endocrinology / European Federation of Endocrine Societies》2005,153(6):845-852
OBJECTIVE: To determine the frequency of mutations of the gonadotropin-releasing hormone receptor (GnRHR) and of the G protein-coupled receptor 54 (GPR54) genes in normosmic idiopathic hypogonadotropic hypogonadism (IHH). METHODS: In a retrospective study we analyzed the GnRHR and the GPR54 genes of 45 IHH patients and 50 controls. Genomic DNA was amplified by PCR to obtain partially overlapping amplicons encompassing the exon-intron boundaries of the GnRHR and GPR54 genes and analyzed by single-stranded conformation polymorphism gel electrophoresis and/or DNA sequencing. RESULTS: One heterozygous R262Q mutation of the GnRHR gene was identified in one patient with familial IHH. The silent single-nucleotide polymorphism (SNP) 453C > T occurred at the same frequency in patients and controls. One patient with sporadic IHH and consanguineous parents showed a novel homozygous sequence variation of the GPR54 gene (1001_1002insC) resulting in an open reading frame shift and elongation of 43 amino acids with an increased number of proline residues in the intracellular receptor domain. This patient had delayed puberty, low testosterone (3.4 nmol/l), and low-normal LH and FSH levels responsive to GnRH. Pulsatile GnRH administration normalized testosterone levels and induced spermatogenesis sufficiently to induce a pregnancy with assisted reproduction. Two common SNPs in exon 1 and exon 5 of the GPR54 gene showed similar frequency distribution and hormonal profiles in IHH and controls. CONCLUSIONS: Mutations of the GnRHR and of the GPR54 gene are rare in IHH and should be investigated especially in cases with autosomal recessive transmission. Common SNPs of the GnRHR and GPR54 genes do not play any role in IHH. 相似文献
74.
Carlo Di Mario Nuccia Morici Cosmo Godino Omer Goktekin Corrado Tamburino Rossella Barbagallo David Antoniucci Eberhard Grube Flavio Airoldi Giuseppe Biondi Zoccai Antonio Colombo Giuseppe M Sangiorgi 《Catheterization and cardiovascular interventions》2007,69(3):416-424
OBJECTIVES: The aim of the study was the assessment of the clinical, angiographic and procedural characteristics correlated with freedom from adverse events at 1 year in a real life setting of consecutive bifurcation lesions. BACKGROUND: Even if stent implantation has shown to be superior to conventional balloon angioplasty in most coronary lesions, bifurcation treatment with stent implantation both in main and in side branch (SB) still raises controversy. METHODS: We reviewed the results obtained in a prospective multicenter registry of 150 patients with 158 bifurcation lesions involving a SB of sufficient diameter to be treated, if necessary, with a polymer based paclitaxel eluting stent (PES, TAXUS). Two stents were used in 118 lesions (74.7%). Final kissing balloon inflation was performed in 87/118 lesions (73.7%) and in 30/40 lesions (75.0%) of the 2 and 1 stent group respectively. RESULTS: At 1-year clinical follow-up we observed 4 stent thromboses, all involving the SBs of the 2 stents group (2.7%). Unlike previous reports, revascularization involved the main vessel in the majority of patients (21/150, 14.0%). After an exploratory multivariable analysis the only parameter predictive of target lesion revascularization (TLR) (HR 0.52; CI 95% 0.11-0.86; p = 0.02) and target vessel revascularization (TVR) (HR 0.47; CI 95% 0.14-0.90; p = 0.03) was postprocedural main branch minimal lumen diameter (MB-MLD). CONCLUSIONS: In a real life setting of consecutive bifurcation lesions, thrombosis rate, concentrated in the SB and the 2-stents group, and need for target lesion revascularization remain higher than in less complex lesion subgroups treated with PES. No differences in immediate success and TLR were observed between 2 stents and 1 stent groups. The frequently observed suboptimal stent expansion and final MB-MLD predict 1 year revascularization. 相似文献
75.
Eberhard Gläss 《Journal of cancer research and clinical oncology》1960,63(3):294-310
Zusammenfassung Erwachsene Ratten wurden mit 4-Dimethylaminoazobenzol (“Buttergelb”) gefüttert und die Mitosen der Leberkerne nach Aufnahme
verschiedener Buttergelbmengen (200–1020 mg) auf Chromosomenzahlen und Mitoseanomalien hin untersucht. Um mehr Teilungsstadien
zu erhalten, wurde die Leber 48 Std vor der Fixierung partiell hepatektomiert. Auch in buttergelbbehandelten Rattenlebern
ist ein Mitosemuster vorhanden, dessen Zusammensetzung sich w?hrend der Buttergelbbehandlung in charakteristischer Weise ver?ndert:
Mit steigender Buttergelbdosis nehmen die diploiden Mitosen stark ab (von 44% auf 10%), die aneuploiden Stadien stark zu (von
13% auf 60%). Die Ver?nderungen vom euploiden (diploiden) zum aneuploiden Mitosemuster gehen sprunghaft vor sich, wobei die
erste Reaktionsschwelle nach 300 mg Buttergelbaufnahme liegt. Bei 939 untersuchten aneuploiden Metaphasen finden sich Chromosomenzahlen
zwischen 6 und 192. Von den in diesem Bereich enthaltenen 178 m?glichen aneuploiden Zahlen sind nur 50 realisiert. Die Zahlen
27, 33, 36, 48, 54, 69, 75, 96 sind dabei besonders h?ufig (78,5% aller aneuploiden Metaphasen). Mit steigender Buttergelbdosis
kommen zus?tzlich zu den bereits bevorzugt auftretenden vier aneuploiden Zahlen der unbehandelten Leber weitere aneuploide
Zahlen als bevorzugt hinzu, deren H?ufigkeit mit steigender Dosis ansteigt. Ferner treten neue aneuploide, nicht bevorzugte
Chromosomenzahlen auf. Sowohl für die neuauftretenden, bevorzugten wie nicht bevorzugten Klassen ist eine an bestimmte Buttergelbdosen
gebundene Entstehung charakteristisch.
Mit 4 Textabbildungen 相似文献
76.
Eberhard K. Walther M.D. 《Dysphagia》1995,10(4):275-278
Eighty-one patients were examined after laryngopharyngeal cancer surgery with a sequential computer manometry system using 4-channel-pressure probes. The general swallowing coordination is neither a matter of the oropharyngeal pressure thrust nor of the pharyngeal transit time, but mainly depends on swallowing initiation. The points of interest are both the pharyngeal inlet and outlet. The topographic correlates are the base of the tongue and the upper esophageal sphincter (UES). Resections of the base of the tongue lead to a decrease of volume available for pressure generation, thus reducing the tongue driving force. The swallowing reflex is uncoordinated resulting in dyskinesia of the UES. Compensation may be achieved with a stronger oropharyngeal thrust and/or repeated swallows. Distal resections alter the pharyngoesophageal segment so that a functional obstruction results, combined with lower pressure amplitudes in the hypopharynx, reducing the pressure gradient necessary for bolus flow. This increasing resistance can be overcome by higher propulsive forces in the base of the tongue region. In case of additional lingual defects, deglutition is subject to decompensation, highlighting the major role of the tongue as a pressure generator for bolus passage. 相似文献
77.
Aron H. Lichtman Eberhard Albert Lux Robert McQuade Sandro Rossetti Raymond Sanchez Wei Sun Stephen Wright Elena Kornyeyeva Marie T. Fallon 《Journal of pain and symptom management》2018,55(2):179-188.e1
Context
Prior Phase 2/3 studies found that cannabinoids might provide adjunctive analgesia in advanced cancer patients with uncontrolled pain.Objectives
To assess adjunctive nabiximols (Sativex®), an extract of Cannabis sativa containing two potentially therapeutic cannabinoids (Δ9-tetrahydrocannabinol [27 mg/mL] and cannabidiol [25 mg/mL]), in advanced cancer patients with chronic pain unalleviated by optimized opioid therapy.Methods
Phase 3, double-blind, randomized, placebo-controlled trial in patients with advanced cancer and average pain Numerical Rating Scale scores ≥4 and ≤8 despite optimized opioid therapy. Patients randomized to nabiximols (n = 199) or placebo (n = 198) self-titrated study medications over a two-week period, followed by a three-week treatment period at the titrated dose.Results
Median percent improvements in average pain Numerical Rating Scale score from baseline to end of treatment in the nabiximols and placebo groups were 10.7% vs. 4.5% (P = 0.0854) in the intention-to-treat population (primary variable) and 15.5% vs. 6.3% (P = 0.0378) in the per-protocol population. Nabiximols was statistically superior to placebo on two of three quality-of-life instruments at Week 3 and on all three at Week 5. In exploratory post hoc analyses, U.S. patients, but not patients from the rest of the world, experienced significant benefits from nabiximols on multiple secondary endpoints. Possible contributing factors to differences in nabiximols efficacy include: 1) the U.S. participants received lower doses of opioids at baseline than the rest of the world and 2) the subgroups had different distribution of cancer pain types, which may have been related to differences in pathophysiology of pain. The safety profile of nabiximols was consistent with earlier studies.Conclusions
Although not superior to placebo on the primary efficacy endpoint, nabiximols had benefits on multiple secondary endpoints, particularly in the U.S. patients. Nabiximols might have utility in patients with advanced cancer who receive a lower opioid dose, such as individuals with early intolerance to opioid therapy. 相似文献78.
Cunningham MO Whittington MA Bibbig A Roopun A LeBeau FE Vogt A Monyer H Buhl EH Traub RD 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(18):7152-7157
Basic cellular and network mechanisms underlying gamma frequency oscillations (30-80 Hz) have been well characterized in the hippocampus and associated structures. In these regions, gamma rhythms are seen as an emergent property of networks of principal cells and fast-spiking interneurons. In contrast, in the neocortex a number of elegant studies have shown that specific types of principal neuron exist that are capable of generating powerful gamma frequency outputs on the basis of their intrinsic conductances alone. These fast rhythmic bursting (FRB) neurons (sometimes referred to as "chattering" cells) are activated by sensory stimuli and generate multiple action potentials per gamma period. Here, we demonstrate that FRB neurons may function by providing a large-scale input to an axon plexus consisting of gap-junctionally connected axons from both FRB neurons and their anatomically similar counterparts regular spiking neurons. The resulting network gamma oscillation shares all of the properties of gamma oscillations generated in the hippocampus but with the additional critical dependence on multiple spiking in FRB cells. 相似文献
79.
Karl Egerer Julia Hertzer Eugen Feist Anja Albrecht Paul Eberhard Rudolph Thomas Drner Gerd‐Rüdiger Burmester 《Arthritis care & research》2003,49(4):546-548
Objectives
To determine the usefulness of sE‐selectin as a marker for early diagnosis and stratification of rheumatoid arthritis.Methods
We investigated several markers of disease activity, including circulating adhesion molecules and other standard laboratory tests, in a 2–3 year followup analysis of patients with rheumatoid arthritis.Results
The mean ± SD levels of sE‐selectin (91.68 ± 31.8 ng/ml versus 49.83 ± 14.76 ng/ml) and rheumatoid factor (375.7 ± 394.4 U versus 44.66 ± 37.63 U) were strongly elevated in severe (n = 15) versus mild (n = 7) courses of disease. Statistical calculation of mean and standard deviation revealed that sE‐selectin represents a highly significant marker for the presence of persistent and aggressive disease over time, regardless of therapeutic intervention and observation time points (P = 0.0004). Notably, regression analysis identified constant values for all parameters analyzed and, therefore, a stable course of the disease could be predicted from the beginning.Conclusion
sE‐selectin appears to be a powerful marker to predict the severity of rheumatoid arthritis.80.
Eberhard P. Scholz Patrick Fischer Patrick Lugenbiel Panagiotis Xynogalos Patrick A. Schweizer Daniel Scherer Dierk Thomas Hugo A. Katus Edgar Zitron 《Journal of interventional cardiac electrophysiology》2018,53(3):347-355