755 research outputs found
Moderators of resistance-based exercise programs\u27 effect on sarcopenia-related measures in men with prostate cancer previously or currently undergoing androgen deprivation therapy: An individual patient data meta-analysis
Introduction: Older men with prostate cancer are commonly affected by reductions in lean mass and physical function following androgen deprivation therapy (ADT). Resistance-based exercise programs are critical to counteract the musculoskeletal toxicities derived from prostate cancer treatment and aging. However, there is significant variability in the effects of exercise interventions. Examining demographic and clinical moderators of exercise effects in this patient group can assist in identifying which subgroups of patients benefit most. Therefore, we examined the effects and moderators of resistance-based exercise programs on sarcopenia-related outcomes that included lean mass, skeletal muscle index, physical function, and muscle strength in older men with prostate cancer. Materials and Methods: Data were retrieved from the Predicting OptimaL cAncer RehabIlitation and Supportive care (POLARIS) consortium. For the present study, we included data from trials that examined the effects of supervised resistance-based exercise interventions on lean mass outcomes, muscle strength, and physical function in patients with prostate cancer previously or currently treated with ADT. Linear mixed models were undertaken to analyse the effects of resistance-based exercise programs considering the clustering of patients within studies. Effects were evaluated by regressing the study group on the post-intervention value of the outcome adjusted for the baseline value, while potential moderators were examined by adding the moderator and its interaction term into the regression model. Results: A total of 560 patients with prostate cancer (age: 69.5 ± 7.8 yrs.; body mass index: 28.6 ± 4.0 kg.m−2) previously or currently treated with ADT were included. Resistance-based exercise programs resulted in significant effects on whole-body and appendicular lean mass and the skeletal muscle index (P \u3c 0.05), with improvements observed across different characteristics. Improvements were also observed in 400-m walk and 6-m backwards tandem walk (P \u3c 0.05), with patients presenting with lower baseline levels deriving greater exercise effects on 400-m walk (−19.4 s, 95% confidence interval [CI]: −36.6 to −2.3) and 6-m backwards tandem walk tests (−3.0 s, 95% CI: −5.7 to −0.3). For relative muscle strength, significant exercise effects were observed, with greater effects in younger patients (0.35 kg.kg−1, 95% CI: 0.22 to 0.48). Discussion: Resistance-based exercise programs effectively improve well-known markers of sarcopenia in men with prostate cancer, with specific subgroups of patients, such as those younger and presenting with lower baseline levels of physical function, deriving greater effects on muscle strength and physical function, respectively
Effects and moderators of exercise medicine on cardiometabolic outcomes in men with prostate cancer previously or currently undergoing androgen deprivation therapy: An individual patient data meta-analysis
Purpose: To examine the effects and moderators of exercise effects on cardiometabolic outcomes in men with prostate cancer previously or currently undergoing androgen deprivation therapy (ADT). Results: Seven trials including 560 patients were examined. Exercise resulted in significant effects on whole-body and regional fat mass (P ≤ 0.001). For whole-body fat mass, significant exercise effects were observed in patients who were unmarried (−1.4 kg, P \u3c 0.05) and who presented with higher fat mass levels (−1.0 kg, P \u3c 0.05). For diastolic blood pressure and low-density lipoprotein (LDL), younger (−4.7 mmHg, P \u3c 0.05) and older patients (−0.2 mmol.l-1, P \u3c 0.10) achieved greater effects, respectively. Regarding high-density lipoprotein (HDL), patients undertaking ADT + prostatectomy + radiotherapy derived significant exercise effects (0.3 mmol.l-1, P \u3c 0.05). Conclusions: Exercise effectively reduces fat mass across subgroups of men undergoing or following ADT with different characteristics. For diastolic blood pressure, HDL and LDL, groups based on age and treatment history could be specifically targeted with exercise medicine
Coral Disease and Health Workshop: Coral Histopathology II
The health and continued existence of coral reef ecosystems are threatened by an increasing array of environmental and anthropogenic impacts. Coral disease is one of the prominent causes of increased mortality among reefs globally, particularly in the Caribbean. Although over 40 different coral diseases and syndromes have been reported
worldwide, only a few etiological agents have been confirmed; most pathogens remain unknown and the dynamics of disease transmission, pathogenicity and mortality are not
understood. Causal relationships have been documented for only a few of the coral diseases, while new syndromes continue to emerge. Extensive field observations by coral
biologists have provided substantial documentation of a plethora of new pathologies, but our understanding, however, has been limited to descriptions of gross lesions with names reflecting these observations (e.g., black band, white band, dark spot). To determine etiology, we must equip coral diseases scientists with basic biomedical knowledge and specialized training in areas such as histology, cell biology and pathology. Only through
combining descriptive science with mechanistic science and employing the synthesis epizootiology provides will we be able to gain insight into causation and become equipped to handle the pending crisis.
One of the critical challenges faced by coral disease researchers is to establish a framework to systematically study coral pathologies drawing from the field of diagnostic
medicine and pathology and using generally accepted nomenclature. This process began in April 2004, with a workshop titled Coral Disease and Health Workshop: Developing Diagnostic Criteria co-convened by the Coral Disease and Health Consortium (CDHC), a working group organized under the auspices of the U.S. Coral Reef Task Force, and the International Registry for Coral Pathology (IRCP). The workshop was hosted by the U.S. Geological Survey, National Wildlife Health Center (NWHC) in Madison, Wisconsin and was focused on gross morphology and disease signs observed in the field. A resounding recommendation from the histopathologists participating in the workshop was the urgent need to develop diagnostic criteria that are suitable to move from gross observations to morphological diagnoses based on evaluation of microscopic anatomy. (PDF contains 92 pages
RNA interference in marine and freshwater sponges
Background: The marine sponge Tethya wilhelma and the freshwater sponge Ephydatia muelleri are emerging model organisms to study evolution, gene regulation, development, and physiology in non-bilaterian animal systems. Thus far, functional methods (i.e., loss or gain of function) for these organisms have not been available.
Results: We show that soaking developing freshwater sponges in double-stranded RNA and/or feeding marine and freshwater sponges bacteria expressing double-stranded RNA can lead to RNA interference and reduction of targeted transcript levels. These methods, first utilized in C. elegans, have been adapted for the development and feeding style of easily cultured marine and freshwater poriferans. We demonstrate phenotypic changes result from ‘knocking down’ expression of the actin gene.
Conclusion: This technique provides an easy, efficient loss-of-function manipulation for developmental and gene regulatory studies in these important non-bilaterian animals
Infrared Light Curves of Mira Variable Stars from COBE DIRBE Data
We have used the COBE DIRBE database to derive near- and mid-infrared light
curves for a well-defined sample of 38 infrared-bright Mira variable stars, and
compared with optical data from the AAVSO. In general, the 3.5 micron and 4.9
micron DIRBE bandpasses provide the best S/N light curves, with S/N decreasing
with wavelength at longer wavelengths. At 25 microns, good light curves are
only available for ~10 percent of our stars, and at wavelengths >= 60 microns,
extracting high quality light curves is not possible. The amplitude of
variability is typically less in the near-infrared than in the optical, and
less in the mid-infrared than in the near-infrared, with decreasing amplitude
with increasing wavelength. On average, there are 0.20 +/- 0.01 magnitudes
variation at 1.25 microns and 0.14 +/- 0.01 magnitudes variation at 4.9 micron
for each magnitude variation in V. The observed amplitudes are consistent with
results of recent theoretical models of circumstellar dust shells around Mira
variables. For a few stars in our sample, we find clear evidence of time lags
between the optical and maxima of phase ~ 0.05 - 0.13, with no lags in the
minima. For three stars, mid-infrared maximum appears to occur slightly before
that in the near-infrared,but after optical maximum. We find three examples of
secondary maxima in the rising portions of the DIRBE light curves, all of which
have optical counterparts in the AAVSO data, supporting the hypothesis that
they are due to shocks rather than newly-formed dust layers. We find no
conclusive evidence for rapid (hours to days) variations in the infrared
brightnesses of these stars.Comment: 16 pages, Astronomical Journal, in press, to be publishe
HITRAP: A facility at GSI for highly charged ions
An overview and status report of the new trapping facility for highly charged
ions at the Gesellschaft fuer Schwerionenforschung is presented. The
construction of this facility started in 2005 and is expected to be completed
in 2008. Once operational, highly charged ions will be loaded from the
experimental storage ring ESR into the HITRAP facility, where they are
decelerated and cooled. The kinetic energy of the initially fast ions is
reduced by more than fourteen orders of magnitude and their thermal energy is
cooled to cryogenic temperatures. The cold ions are then delivered to a broad
range of atomic physics experiments.Comment: 8 pages, 11 figure
The dynamical evolution of the circumstellar gas around low-and intermediate-mass stars I: the AGB
We have investigated the dynamical interaction of low- and-intermediate mass
stars (from 1 to 5 Msun) with their interstellar medium (ISM). In this first
paper, we examine the structures generated by the stellar winds during the
Asymptotic Giant Branch (AGB) phase, using a numerical code and the wind
history predicted by stellar evolution. The influence of the external ISM is
also taken into account. We find that the wind variations associated with the
thermal pulses lead to the formation of transient shells with an average
lifetime of 20,000 yr, and consequently do not remain recorded in the density
or velocity structure of the gas. The formation of shells that survive at the
end of the AGB occurs via two main processes: shocks between the shells formed
by two consecutive enhancements of the mass-loss or via continuous accumulation
of the material ejected by the star in the interaction region with the ISM. Our
models show that the mass of the circumstellar envelope increases appreciably
due to the ISM material swept up by the wind (up to 70 % for the 1 Msun stellar
model). We also point out the importance of the ISM on the deceleration and
compression of the external shells. According to our simulations, large regions
(up to 2.5 pc) of neutral gas surrounding the molecular envelopes of AGB stars
are expected. These large regions of gas are formed from the mass-loss
experienced by the star during the AGB evolution.Comment: 43 pages, 15 figures. Accepted for publication in the Astrophysical
Journa
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