52 research outputs found
Effect of aging on endogenous level of 5 alpha-dihydrotestosterone, testosterone, estradiol, and estrone in epithelium and stroma of normal and hyperplastic human prostate.
associated with aging. Thus, the question arises whether or not a
correlation exists between the well known prostatic androgen and
estrogen accumulation and aging. To address this question, we measured
5a-dihydrotestosterone (DHT), testosterone, estradiol, and estrone
in epithelium and stroma of six normal (NPR) and 19 BPH and
correlated the values with the age of the donors (26-87 yr). The mean
DHT level in NPR epithelium was significantly higher than in NPR
stroma, and also significantly higher than in epithelium and stroma of
BPH. The epithelial DHT level of NPR and BPH decreased with age,
the correlation being statistically significant. The stromal DHT level
of NPR and BPH showed no correlation with age. Concerning testosterone,
generally rather low values were found which showed no correlation
with age. The mean levels of estradiol and estrone were
significantly higher in BPH stroma as compared to BPH epithelium
as well as to NPR epithelium and stroma. In NPR, the mean levels of
estradiol and estrone were significantly higher in epithelium than
stroma. In NPR and BPH, the stromal estradiol and estrone levels
increased significantly with age. In epithelium such a correlation between
the estrogen levels and age was not found. Our results indicate
that the prostatic accumulation of DHT, estradiol, and estrone is in
part intimately correlated with aging, leading with increasing age to a
dramatic increase of the estrogen/androgen ratio particularly in stroma
of BPH
Effect of Growth Hormone (hGH) Replacement Therapy on Physical Work Capacity and Cardiac and Pulmonary Function in Patients with hGH Deficiency Acquired in Adulthood.
The effects of 6 months of replacement therapy with recombinant human GH (hGH) on physical work capacity and cardiac structure and function were investigated in 20 patients with hGH deficiency of adult onset in a double blind, placebo-controlled trial. The GH dose of 12.5 micrograms/kg BW was self-administered daily sc. Oxygen consumption (VO2), CO2 production, and ventilatory volumes were measured during exercise on a bicycle spiroergometer. M-Mode echocardiography was performed using standard techniques. The VO2 max data, expressed per kg BW (mL/min.kg BW) showed a significant increase from 23.2 +/- 2.4 to 30.0 +/- 2.3 (P < 0.01) in the hGH-treated group, whereas the VO2 max data, expressed per lean body mass (milliliters per min/kg lean body mass) did not change significantly in either group. Maximal O2 pulse (milliliters per beat) increased significantly from 15.2 +/- 5.6 to 19.6 +/- 3.3 mL/beat (P < 0.01), but remained constant in the placebo group. The maximal power output (watts +/- SE) increased significantly (P < 0.01) from 192.5 +/- 13.5 to 227.5 +/- 11.5 in the hGH-treated group, but remained constant in the placebo group. Cardiac structure (left ventricular posterior wall, interventricular septum thickness, left ventricular mass, left ventricular end-systolic dimension, and left ventricular end-diastolic dimension) as well as echocardiographically assessed cardiac function did not change significantly after 6 months of treatment in either group. We conclude that hGH replacement in hGH-deficient adults improves oxygen uptake and exercise capacity. These improvements in pulmonary parameters might be due to an increase in respiratory muscle strength and partly to the changes in muscle volume per se observed during hGH replacement therapy. Furthermore, an increased cardiac output might contribute to the improvement in exercise performance during hGH treatment. According to our data, hGH replacement therapy leads to an improvement of exercise capacity and maximal oxygen uptake, but has no significant effect on cardiac structure
(R p)-1-{(R)-(Dimethylamino)[2-(diphenylphosphanyl)phenyl]methyl}-2-(diphenylphosphanyl)ferrocene chloroform solvate
The absolute configuration of the title molecule, [Fe(C5H5)(C38H34NP2)]·CHCl3, is R,R
p. The molecular structure is similar to the structure of the solvent-free compound [Fukuzawa, Yamamoto & Kikuchi (2007 ▶). J. Org. Chem. 72, 1514–1517], but some torsion angles about the P—Cphenyl bonds differ by up to 25°. The P atoms and the N atom have a distorted trigonal-pyramidal geometry. The chloroform solvate group donates a C—H⋯π bond to the central benzene ring and is also involved in six intermolecular C—H⋯Cl contacts with H⋯Cl distances between 2.96 and 3.13 Å
A gas analyzer for the internal polarized target of the HERMES experiment
A gas analyzer has been developed for the internal polarized target of the HERMES experiment at DESY in order to determine the relative amount of atomic and molecular hydrogen or deuterium in a gas sample. The precise quantitative knowledge of this ratio is crucial because the nucleons in atoms and molecules contribute differently to the average nuclear polarization of the target gas. A new calibration technique used to derive the relative sensitivity to atoms and molecules is presented. As an example, it is shown how the gas analyzer is used within the HERMES environment to divide the molecules in the gas sample into an unpolarized and a potentially polarized fraction
First Search for Axion-Like Particles in a Storage Ring Using a Polarized Deuteron Beam
Based on the notion that the local dark-matter field of axions or axion-like
particles (ALPs) in our Galaxy induces oscillating couplings to the spins of
nucleons and nuclei (via the electric dipole moment of the latter and/or the
paramagnetic axion-wind effect), we performed the first experiment to search
for ALPs using a storage ring. For that purpose, we used an in-plane polarized
deuteron beam stored at the Cooler Synchrotron COSY, scanning momenta near 970
MeV/c. This entailed a scan of the spin precession frequency. At resonance
between the spin precession frequency of deuterons and the ALP-induced EDM
oscillation frequency there will be an accumulation of the polarization
component out of the ring plane. Since the axion frequency is unknown, the
momentum of the beam and consequently the spin precession frequency were ramped
to search for a vertical polarization change that would occur when the
resonance is crossed. At COSY, four beam bunches with different polarization
directions were used to make sure that no resonance was missed because of the
unknown relative phase between the polarization precession and the axion/ALP
field. A frequency window of 1.5-kHz width around the spin precession frequency
of 121 kHz was scanned. We describe the experimental procedure and a test of
the methodology with the help of a radiofrequency Wien filter located on the
COSY ring. No ALP resonance was observed. As a consequence an upper limit of
the oscillating EDM component of the deuteron as well as its axion coupling
constants are provided.Comment: 25 pages, 24 figures, 7 tables, 67 reference
Conception of data archiving and management for geological mapping of Martian surface illustrated by an “analysis and interpretation of valley networks on Mars”
Conception of a geo-database as well as an application-oriented query system for geological mapping of Martian surface illustrated by an “analysis and interpretation of valley networks on Mars”
Mars raises special attention in the field of planetary research because of its geological similarity to Earth. Based
on this increasing interest, the rapid technical development as well as the increase of missions to Mars, more
different but complementary datasets are collected (e.g. images, digital terrain models, spectral data, maps etc.).
This datasets get more and more quantified and evaluation yield complex mapping interpretations and results.
For a better and more efficient use of this great quantity of data (basis data, different analysis methods, and
derived information) a database concept to combine and correlate different data, maps and interpretations is being
developed and will be presented here. "The analysis and interpretation of valley networks on Mars" is used as
working example for the database conception.
The first step will enable the user to create an individually useable database by a special query system.
Based on this data collection multi-dimensional mapping needed for the interpretation can then be executed. After
completion of this task the results will be stored in the database, defined as metadata. Through this the results will
be available as secondary base data for further cross-correlations of basic and derived data to add additional values
in interpretation
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