41 research outputs found
Low Intensity Resistance Exercise Training with Blood Flow Restriction: Insight into Cardiovascular Function, and Skeletal Muscle Hypertrophy in Humans
Attenuated functional exercise capacity in elderly and diseased populations is a common problem, and stems primarily from physical inactivity. Decreased function and exercise capacity can be restored by maintaining muscular strength and mass, which are key factors in an independent and healthy life. Resistance exercise has been used to prevent muscle loss and improve muscular strength and mass. However, the intensities necessary for traditional resistance training to increase muscular strength and mass may be contraindicated for some at risk populations, such as diseased populations and the elderly. Therefore, an alternative exercise modality is required. Recently, blood flow restriction (BFR) with low intensity resistance exercise (LIRE) has been used for such special populations to improve their function and exercise capacity. Although BFR+LIRE has been intensively studied for a decade, a comprehensive review detailing the effects of BFR+LIRE on both skeletal muscle and vascular function is not available. Therefore, the purpose of this review is to discuss previous studies documenting the effects of BFR+LIRE on hormonal and transcriptional factors in muscle hypertrophy and vascular function, including changes in hemodynamics, and endothelial function
Two Years after the <i>Hebei Spirit</i> Oil Spill: Residual Crude-Derived Hydrocarbons and Potential AhR-Mediated Activities in Coastal Sediments
The <i>Hebei Spirit</i> oil spill occurred
in December
2007 approximately 10 km off the coast of Taean, South Korea, on the
Yellow Sea. However, the exposure and potential effects remain largely
unknown. A total of 50 surface and subsurface sediment samples were
collected from 22 sampling locations at the spill site in order to
determine the concentration, distribution, composition of residual
crudes, and to evaluate the potential ecological risk after two years
of oil exposure. Samples were extracted and analyzed for 16 polycyclic
aromatic hydrocarbons (PAHs), 20 alkyl-PAHs, 15 aliphatic hydrocarbons,
and total petroleum hydrocarbons using GC-MSD. AhR-mediated activity
associated with organic sediment extracts was screened using the H4IIE-<i>luc</i> cell bioassay. The response of the benthic invertebrate
community was assessed by mapping the macrobenthic fauna. Elevated
concentrations of residual crudes from the oil spill were primarily
found in muddy bottoms, particularly in subsurface layers. In general,
the bioassay results were consistent with the chemistry data in a
dose-dependent manner, although the mass-balance was incomplete. More
weathered samples containing greater fractions of alkylated PAHs exhibited
greater AhR activity, due to the occurrence of recalcitrant AhR agonists
present in residual oils. The macrobenthic population distribution
exhibits signs of species-specific tolerances and/or recolonization
of certain species such as <i>Batillaria</i> during weathering
periods. Although the <i>Hebei Spirit</i> oil spill was
a severe oil exposure, it appears the site is recovering two years
later