586 research outputs found
Insulin Resistance and Cancer-Specific and All-Cause Mortality in Postmenopausal Women: The Women\u27s Health Initiative
© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please email: [email protected]. BACKGROUND: Insulin resistance has been proposed as a mediator of the increased cancer incidence and mortality associated with obesity. However, prior studies included limited cancer deaths and had inconsistent findings. Therefore, we evaluated insulin resistance and cancer-specific and all-cause mortality in postmenopausal women participating in the Women\u27s Health Initiative (WHI). METHODS: Eligible were a subsample of 22 837 WHI participants aged 50-79âyears enrolled at 40 US clinical centers from 1993 to 1998 who had baseline fasting glucose and insulin levels. Baseline insulin resistance was measured by the homeostasis model assessment of insulin resistance (HOMA-IR). Cancers were verified by central medical record review and deaths verified by medical record and death certificate review enhanced by National Death Index queries. Cox proportional hazards regression models were used to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer-specific and all-cause mortality. All statistical tests were two-sided. RESULTS: During a median of 18.9âyears of follow-up, 1820 cancer deaths and 7415 total deaths occurred. Higher HOMA-IR quartile was associated with higher cancer-specific mortality (Q4 vs Q1, HRâ=â1.26, 95% CIâ=â1.09 to 1.47; Ptrend = .003) and all-cause mortality (Q4 vs Q1, HRâ=â1.63, 95% CIâ=â1.51 to 1.76; Ptrend \u3c .001). A sensitivity analysis for diabetes status did not change findings. Among women with body mass index less than 25âkg/m2, higher HOMA-IR quartile was associated with higher cancer mortality (Fine and Gray, Pâ=â.004). CONCLUSIONS: High insulin resistance, as measured by HOMA-IR, identifies postmenopausal women at higher risk for cancer-specific and all-cause mortality who could potentially benefit from early intervention
Genetic variants in the MRPS30 region and postmenopausal breast cancer risk
Abstract{no abstract
Quasi-simultaneous XMM-Newton and VLA observation of the non-thermal radio emitter HD\168112 (O5.5III(f^+))
We report the results of a multiwavelength study of the non-thermal radio
emitter HD168112 (O5.5III(f^+)). The detailed analysis of two
quasi-simultaneous XMM-Newton and VLA observations reveals strong variability
of this star both in the X-ray and radio ranges. The X-ray observations
separated by five months reveal a decrease of the X-ray flux of ~30%. The radio
emission on the other hand increases by a factor 5-7 between the two
observations obtained roughly simultaneously with the XMM-Newton pointings. The
X-ray data reveal a hard emission that is most likely produced by a thermal
plasma at kT ~2-3 keV while the VLA data confirm the non-thermal status of this
star in the radio waveband. Comparison with archive X-ray and radio data
confirms the variability of this source in both wavelength ranges over a yet
ill defined time scale. The properties of HD168112 in the X-ray and radio
domain point towards a binary system with a significant eccentricity and an
orbital period of a few years. However, our optical spectra reveal no
significant changes of the star's radial velocity suggesting that if HD168112
is indeed a binary, it must be seen under a fairly low inclination.Comment: 17 pages, 11 figures (10 postscript + 1 gif
Whole Earth Telescope observations of the hot helium atmosphere pulsating white dwarf EC 20058-5234
We present the analysis of a total of 177h of high-quality optical
time-series photometry of the helium atmosphere pulsating white dwarf (DBV) EC
20058-5234. The bulk of the observations (135h) were obtained during a WET
campaign (XCOV15) in July 1997 that featured coordinated observing from 4
southern observatory sites over an 8-day period. The remaining data (42h) were
obtained in June 2004 at Mt John Observatory in NZ over a one-week observing
period. This work significantly extends the discovery observations of this
low-amplitude (few percent) pulsator by increasing the number of detected
frequencies from 8 to 18, and employs a simulation procedure to confirm the
reality of these frequencies to a high level of significance (1 in 1000). The
nature of the observed pulsation spectrum precludes identification of unique
pulsation mode properties using any clearly discernable trends. However, we
have used a global modelling procedure employing genetic algorithm techniques
to identify the n, l values of 8 pulsation modes, and thereby obtain
asteroseismic measurements of several model parameters, including the stellar
mass (0.55 M_sun) and T_eff (~28200 K). These values are consistent with those
derived from published spectral fitting: T_eff ~ 28400 K and log g ~ 7.86. We
also present persuasive evidence from apparent rotational mode splitting for
two of the modes that indicates this compact object is a relatively rapid
rotator with a period of 2h. In direct analogy with the corresponding
properties of the hydrogen (DAV) atmosphere pulsators, the stable low-amplitude
pulsation behaviour of EC 20058 is entirely consistent with its inferred
effective temperature, which indicates it is close to the blue edge of the DBV
instability strip. (abridged)Comment: 19 pages, 8 figures, 5 tables, MNRAS accepte
Association between dietary inflammatory potential and breast cancer incidence and death: results from the Women\u27s Health Initiative
BACKGROUND: Diet modulates inflammation and inflammatory markers have been associated with cancer outcomes. In the Women\u27s Health Initiative, we investigated associations between a dietary inflammatory index (DII) and invasive breast cancer incidence and death.
METHODS: The DII was calculated from a baseline food frequency questionnaire in 122 788 postmenopausal women, enrolled from 1993 to 1998 with no prior cancer, and followed until 29 August 2014. With median follow-up of 16.02 years, there were 7495 breast cancer cases and 667 breast cancer deaths. We used Cox regression to estimate multivariable-adjusted hazards ratios (HRs) and 95% confidence intervals (95% CIs) by DII quintiles (Q) for incidence of overall breast cancer, breast cancer subtypes, and deaths from breast cancer. The lowest quintile (representing the most anti-inflammatory diet) was the reference.
RESULTS: The DII was not associated with incidence of overall breast cancer (HRQ5vsQ1, 0.99; 95% CI, 0.91-1.07; Ptrend=0.83 for overall breast cancer). In a full cohort analysis, a higher risk of death from breast cancer was associated with consumption of more pro-inflammatory diets at baseline, after controlling for multiple potential confounders (HRQ5vsQ1, 1.33; 95% CI, 1.01-1.76; Ptrend=0.03).
CONCLUSIONS: Future studies are needed to examine the inflammatory potential of post-diagnosis diet given the suggestion from the current study that dietary inflammatory potential before diagnosis is related to breast cancer death
Third Order Effect of Rotation on Stellar Oscillations of a -Cephei Star
Here the effect of rotation up to third order in the angular velocity of a
star on the p, f and g modes is investigated. To do this, the third-order
perturbation formalism presented by Soufi et al. (1998) and revised by Karami
(2008), was used. I quantify by numerical calculations the effect of rotation
on the oscillation frequencies of a uniformly rotating -Cephei star with
12 . For an equatorial velocity of 90 , it is found
that the second- and third-order corrections for , for instance,
are of order of 0.07% of the frequency for radial order and reaches up
to 0.6% for .Comment: 13 pages, 2 figures, 10 table
Stellar winds from Massive Stars
We review the various techniques through which wind properties of massive
stars - O stars, AB supergiants, Luminous Blue Variables (LBVs), Wolf-Rayet
(WR) stars and cool supergiants - are derived. The wind momentum-luminosity
relation (e.g. Kudritzki et al. 1999) provides a method of predicting mass-loss
rates of O stars and blue supergiants which is superior to previous
parameterizations. Assuming the theoretical sqrt(Z) metallicity dependence,
Magellanic Cloud O star mass-loss rates are typically matched to within a
factor of two for various calibrations. Stellar winds from LBVs are typically
denser and slower than equivalent B supergiants, with exceptional mass-loss
rates during giant eruptions Mdot=10^-3 .. 10^-1 Mo/yr (Drissen et al. 2001).
Recent mass-loss rates for Galactic WR stars indicate a downward revision of
2-4 relative to previous calibrations due to clumping (e.g. Schmutz 1997),
although evidence for a metallicity dependence remains inconclusive (Crowther
2000). Mass-loss properties of luminous (> 10^5 Lo) yellow and red supergiants
from alternative techniques remain highly contradictory. Recent Galactic and
LMC results for RSG reveal a large scatter such that typical mass-loss rates
lie in the range 10^-6 .. 10^-4 Mo/yr, with a few cases exhibiting 10^-3 Mo/yr.Comment: 16 pages, 2 figures, Review paper to appear in Proc `The influence of
binaries on stellar population studies', Brussels, Aug 2000 (D. Vanbeveren
ed.), Kluwe
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