8,002 research outputs found
Eicosapentaenoic acid and oxypurinol in the treatment of muscle wasting in a mouse model of cancer cachexia
Cancer cachexia is a wasting condition, driven by systemic inflammation and oxidative stress. This study investigated eicosapentaenoic acid (EPA) in combination with oxypurinol as a treatment in a mouse model of cancer cachexia. Mice with cancer cachexia were randomized into 4 treatment groups (EPA (0.4 g/kg/day), oxypurinol (1 mmol/L ad-lib), combination, or control), and euthanized after 29 days. Analysis of oxidative damage to DNA, mRNA analysis of pro-oxidant, antioxidant and proteolytic pathway components, along with enzyme activity of pro- and antioxidants were completed on gastrocnemius muscle. The control group displayed earlier onset of tumor compared to EPA and oxypurinol groups (P<0.001). The EPA group maintained body weight for an extended duration (20 days) compared to the oxypurinol (5 days) and combination (8 days) groups (P<0.05). EPA (18.2±3.2 pg/ml) and combination (18.4±3.7 pg/ml) groups had significantly higher 8-OH-dG levels than the control group (12.9±1.4 pg/ml, P≤0.05) indicating increased oxidative damage to DNA. mRNA levels of GPx1, MURF1 and MAFbx were higher following EPA treatment compared to control (P≤0.05). Whereas oxypurinol was associated with higher GPx1, MnSOD, CAT, XDH, MURF1, MAFbx and UbB mRNA compared to control (P≤0.05). Activity of total SOD was higher in the oxypurinol group (32.2±1.5 U/ml) compared to control (27.0±1.3 U/ml, P<0.01), GPx activity was lower in the EPA group (8.76±2.0 U/ml) compared to control (14.0±1.9 U/ml, P<0.05), and catalase activity was lower in the combination group (14.4±2.8 U/ml) compared to control (20.9±2.0 U/ml, P<0.01). There was no change in XO activity. The increased rate of weight decline in mice treated with oxypurinol indicates that XO may play a protective role during the progression of cancer cachexia, and its inhibition is detrimental to outcomes. In combination with EPA, there was little significant improvement from control, indicating oxypurinol is unlikely to be a viable treatment compound in cancer cachexia.<br /
Ultrafast Spin Density Wave Transition in Chromium Governed by Thermalized Electron Gas
The energy and momentum selectivity of time- and angle-resolved photoemission
spectroscopy is exploited to address the ultrafast dynamics of the
antiferromagnetic spin density wave (SDW) transition photoexcited in epitaxial
thin films of chromium. We are able to quantitatively extract the evolution of
the SDW order parameter Δ through the ultrafast phase transition and show that
Δ is governed by the transient temperature of the thermalized electron gas, in
a mean field description. The complete destruction of SDW order on a sub-100
fs time scale is observed, much faster than for conventional charge density
wave materials. Our results reveal that equilibrium concepts for phase
transitions such as the order parameter may be utilized even in the strongly
nonadiabatic regime of ultrafast photoexcitation
Palliative Care Consultations in Nursing Homes and Reductions in Acute Care Use and Potentially Burdensome End-of-Life Transitions
To evaluate how receipt and timing of nursing home (NH) palliative care consults (primarily by nurse practitioners with palliative care expertise) is associated with end-of-life care transitions and acute care us
Use of cumulative incidence of novel influenza A/H1N1 in foreign travelers to estimate lower bounds on cumulative incidence in Mexico
Background: An accurate estimate of the total number of cases and severity of illness of an emerging infectious disease is
required both to define the burden of the epidemic and to determine the severity of disease. When a novel pathogen first
appears, affected individuals with severe symptoms are more likely to be diagnosed. Accordingly, the total number of cases
will be underestimated and disease severity overestimated. This problem is manifest in the current epidemic of novel
influenza A/H1N1.
Methods and Results: We used a simple approach to leverage measures of incident influenza A/H1N1 among a relatively
small and well observed group of US, UK, Spanish and Canadian travelers who had visited Mexico to estimate the incidence
among a much larger and less well surveyed population of Mexican residents. We estimate that a minimum of 113,000 to
375,000 cases of novel influenza A/H1N1 have occurred in Mexicans during the month of April, 2009. Such an estimate
serves as a lower bound because it does not account for underreporting of cases in travelers or for nonrandom mixing
between Mexican residents and visitors, which together could increase the estimates by more than an order of magnitude.
Conclusions: We find that the number of cases in Mexican residents may exceed the number of confirmed cases by two to
three orders of magnitude. While the extent of disease spread is greater than previously appreciated, our estimate suggests
that severe disease is uncommon since the total number of cases is likely to be much larger than those of confirmed cases
Nutritional Quality of Leaves and Unripe Fruit Consumed as Famine Foods by the Flying Foxes of Samoa
Many tropical herbivores alter their diets throughout the year in
response to different levels of food availability. Fruit bats, including Pteropus
samoensis Peale and Pteropus tonganus Quoy & Gaimard, are phytophagous
species that may increase their consumption of foods such as unripe fruit and
leaves in periods of low fruit diversity and volume. These periods include the
tropical dry season or following the frequent hurricanes that batter the Samoan
Archipelago. We examined the nutritional composition of leaves and immature
fruits and compared the levels of organic and mineral nutrients with those of
ripe fruit. We used principal components analysis (PCA) to examine patterns
of variation in nutrient components of leaves, unripe fruit, and ripe fruit, as
well as to compare the mean levels of nutrients. Overall, unripe fruit provided
levels of nutrients comparable with those of ripe fruit of the same species for
many organic and mineral components. Unripe fruit were only half as rich in
iron as ripe fruit, but unripe fruit had high levels of calcium compared with
ripe fruit of the same species. Leaves are often cited as a rich source of protein
for fruit bats, and our results were consistent with this suggestion. Leaves were
also found to be rich in zinc, manganese, and calcium. Therefore, flying foxes
and other herbivores probably do not avoid unripe fruits and leaves because of
their low nutrient levels. It may be that these famine foods are not normally
consumed because of the presence of secondary compounds, low concentrations
of palatable sugars, or a distasteful and hard pericarp on unripe fruits
Palliative Care Consultations in Nursing Homes and End-of-Life Hospitalizations
While specialty palliative care in hospital and outpatient settings is associated with lower acute care use, its impact in U.S. nursing homes (NHs) is unknown
Laser frequency noise characterisation using high-finesse plano-concave optical microresonators
Characterising laser frequency noise is essential for applications including optical sensing and coherent optical communications. Accurate measurement of ultranarrow linewidth lasers over a wide frequency range using existing methods is still challenging. Here we present a method for characterising the frequency noise of lasers using a high finesse plano-concave optical microresonator (PCMR) acting as frequency discriminator. To enable noise measurements at a wide range of laser frequencies, an array of PCMRs was produced with slight variations of thickness resulting in a series of discriminators operating at a series of periodical frequencies. This method enables measuring the frequency noise over a wide linewidth range (15Hz to <100MHz) over the 1440nm-1630nm wavelength range. To assess the performance of the method, four different lasers were characterised, and the results were compared to the estimations of a commercial frequency noise analyser
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