39 research outputs found
Menopausal stage differences in endothelial resistance to ischemia‐reperfusion injury
Background
In postmenopausal women, reduced ovarian function precedes endothelial dysfunction and attenuated endothelial resistance to ischemia-reperfusion (IR) injury. We hypothesized that IR injury would lower endothelial function, with premenopausal women demonstrating the greatest protection from injury, followed by early, then late postmenopausal women.
Methods
Flow-mediated dilation (FMD) was assessed at baseline and following IR injury in premenopausal (n = 11), early (n = 11; 4 ± 1.6 years since menopause), and late (n = 11; 15 ± 5.5 years since menopause) postmenopausal women.
Results
There were significant group differences in baseline FMD (p = 0.007); post hoc analysis revealed a similar resting FMD between premenopausal (7.8% ± 2.1%) and early postmenopausal (7.1% ± 2.7%), but significantly lower FMD in late postmenopausal women (4.5% ± 2.3%). Results showed an overall decline in FMD after IR injury (p < 0.001), and a significant condition*time interaction (p = 0.048), with early postmenopausal women demonstrating the most significant decline in FMD following IR.
Conclusion
Our findings indicate that endothelial resistance to IR injury is attenuated in healthy early postmenopausal women
Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy
We review HB stars in a broad astrophysical context, including both variable
and non-variable stars. A reassessment of the Oosterhoff dichotomy is
presented, which provides unprecedented detail regarding its origin and
systematics. We show that the Oosterhoff dichotomy and the distribution of
globular clusters (GCs) in the HB morphology-metallicity plane both exclude,
with high statistical significance, the possibility that the Galactic halo may
have formed from the accretion of dwarf galaxies resembling present-day Milky
Way satellites such as Fornax, Sagittarius, and the LMC. A rediscussion of the
second-parameter problem is presented. A technique is proposed to estimate the
HB types of extragalactic GCs on the basis of integrated far-UV photometry. The
relationship between the absolute V magnitude of the HB at the RR Lyrae level
and metallicity, as obtained on the basis of trigonometric parallax
measurements for the star RR Lyrae, is also revisited, giving a distance
modulus to the LMC of (m-M)_0 = 18.44+/-0.11. RR Lyrae period change rates are
studied. Finally, the conductive opacities used in evolutionary calculations of
low-mass stars are investigated. [ABRIDGED]Comment: 56 pages, 22 figures. Invited review, to appear in Astrophysics and
Space Scienc
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NEUTROPHIL ACTIVATION AND SECONDARY PULMONARY INJURY AFTER PENETRATING ABDOMINAL TRAUMA
Exercise-induced vasodilation is associated with menopause stage in healthy middle-aged women
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Single and 7-day handgrip and squat exercise prevents endothelial ischaemia-reperfusion injury in individuals with cardiovascular disease risk factors
Background: Whole-body exercise provides protection against endothelial ischemia-reperfusion (IR) injury. In this crossover study, we examined the effects of 1) single bout of local exercise (handgrip, squats) on endothelial responses to IR , and 2) if 7 days of daily exercise bolsters these effects in individuals with cardiovascular disease (CVD) risk factors. Methods: Fifteen participants (9 women, 58±5 years, ≥2 CVD risk factors) attended the laboratory for 6 visits. On the control visit, brachial artery flow-mediated dilation (FMD) was measured before and after IR. One week later, participants were randomized to 4x5-min unilateral handgrip (50% maximal voluntary contraction, 25 rpm) or squat exercises (15 rpm), followed by IR plus FMD measurements. Subsequently, home-based exercise was performed (six days), followed by a laboratory visit for the IR protocol plus FMD measurements (18-24 h after). There was a two-week washout period between exercise mode. Results: For a single exercise bout, we found a significant IR injury*exercise mode interaction (P0.05). Conclusions: Single bouts of local exercise provides remote protection against IR-induced injury in individuals with CVD risk factors, with one-week daily, home-based exercise preserving these effects for up to 24h following the last bout