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991.
S. Kim M.J. Graham R.G. Lee L. Yang S. Kim V. Subramanian J.D. Layne L. Cai R.E. Temel D. Shih A.J. Lusis J.A. Berliner S. Lee 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(3):306-315
Background and aims
Heparin-binding EGF-like growth factor (HB-EGF) is a representative EGF family member that interacts with EGFR under diverse stress environment. Previously, we reported that the HB-EGF-targeting using antisense oligonucleotide (ASO) effectively suppressed an aortic aneurysm in the vessel wall and circulatory lipid levels. In this study, we further examined the effects of the HB-EGF ASO administration on the development of hyperlipidemia-associated atherosclerosis using an atherogenic mouse model.Methods and results
The male and female LDLR deficient mice under Western diet containing 21% fat and 0.2% cholesterol content were cotreated with control and HB-EGF ASOs for 12 weeks. We observed that the HB-EGF ASO administration effectively downregulated circulatory VLDL- and LDL-associated lipid levels in circulation; concordantly, the HB-EGF targeting effectively suppressed the development of atherosclerosis in the aorta. An EGFR blocker BIBX1382 administration suppressed the hepatic TG secretion rate, suggesting a positive role of the HB-EGF signaling for the hepatic VLDL production. We newly observed that there was a significant improvement of the insulin sensitivity by the HB-EGF ASO administration in a mouse model under the Western diet as demonstrated by the improvement of the glucose and insulin tolerances.Conclusion
The HB-EGF ASO administration effectively downregulated circulatory lipid levels by suppressing hepatic VLDL production rate, which leads to effective protection against atherosclerosis in the vascular wall. 相似文献992.
993.
Bo Yang Elizabeth L. Norton Terry Shih Linda Farhat Xiaoting Wu Whitney E. Hornsby Karen M. Kim Himanshu J. Patel G. Michael Deeb 《The Journal of thoracic and cardiovascular surgery》2019,157(4):1313-1321.e2
Objective
To compare perioperative and long-term outcomes in patients undergoing hemiarch and aggressive arch replacement for acute type A aortic dissection (ATAAD).Methods
From 1996 to 2017, we compared outcomes of hemiarch (n = 322) versus aggressive arch replacements (zones 2 and 3 arch replacement with implantation of 2-4 arch branches, n = 150) in ATAAD. Indications for aggressive arch were arch aneurysm >4 cm or intimal tear in the aortic arch that was not resectable by hemiarch replacement, or dissection of arch branches with malperfusion.Results
Patients in the aggressive arch group were significantly younger (mean age: 57 vs 61 years old) and had significantly longer hypothermic circulatory arrest, cardiopulmonary bypass, and aortic crossclamp times. There were no significant differences in perioperative outcomes between hemiarch and aggressive arch groups, including 30-day mortality (5.3% vs 7.3%, P = .38) and postoperative stroke rate (7% vs 7%, P = .96). Over 15 years, Kaplan–Meier survival was similar between hemiarch and aggressive arch groups (log-rank P = .55, 10-year survival 70% vs 72%). Given death as a competing factor, incidence rates of reoperation over 15 years (2.1% vs 2.0% per year, P = 1) and 10-year cumulative incidence of reoperation (14% vs 12%, P = .89) for arch and distal aorta pathology were similar between the 2 groups.Conclusions
Both hemiarch and aggressive arch replacement are appropriate approaches for select patients with ATAAD. Aggressive arch replacement should be considered for an arch aneurysm >4 cm or an intimal tear at the arch unable to be resected by hemiarch replacement, or dissection of the arch branches with malperfusion. 相似文献994.
995.
Cerebrovascular reactivity (CVR) can give insight into the cerebrovascular function. CVR can be estimated by measuring a blood‐oxygen‐level‐dependent (BOLD) response combined with breath‐holding (BH). The reproducibility of this technique has been addressed and existing studies have focused on short‐term reproducibility using a 3 T magnetic resonance imaging (MRI) system. However, little is known about the long‐term reproducibility of this procedure and the corresponding reproducibility using a 1.5 T MRI system. Here, we systematically examined the short‐ and long‐term reproducibility of BOLD responses to BH across field strengths. Nine subjects participated in three MRI sessions separated by 30 minutes (sessions 1 and 2: short term) and 68–92 days (sessions 1 and 3, long term) at both 1.5 and 3 T MRI. Our findings revealed that significant differences between field strengths were detected in the activated gray matter volume and BOLD signal change (both P < 0.001), with smaller magnitudes at 1.5 T. However, activation patterns were reproducible, independent of the time interval, brain region or field strength. All interscan coefficient of variation values were below the 33% fiducial limit, and the intraclass correlation coefficient values were above 0.4, which is usually considered the acceptability limit in functional studies. These findings suggest that the response of BOLD signal to BH for assessing CVR is reproducible over time at 1.5 and 3 T. This technique can be considered a tool for monitoring longitudinal changes in patients with cerebrovascular diseases, and its use should be encouraged for clinical 1.5 T MRI systems. 相似文献
996.
997.
Wen-Shiuan Shih Chueh-Hung Wu Tyng-Guey Wang 《Journal of Science and Medicine in Sport》2019,22(4):392-396
Objectives
Among symptomatic dancers, sonographic abnormalities are common. Whether asymptomatic dancers have any abnormalities remains unknown. Some dancers became cyanosis over distal feet after ballet training. The hemodynamic changes at the feet in ballet are not clearly understood.Design
Cross-sectional study.Methods
In 25 dancers and 14 non-dancers, B-mode ultrasonography was used to measure cross-sectional areas (CSA) of tendons of deep posterior compartment muscles. Doppler ultrasonography was used to measure peak velocity (Vpeak) of posterior tibial artery in three ankle postures: the neutral position, passively and forced actively plantar flexion (en pointe). The big toe oxygen saturation was recorded in neutral position and during 1-min en pointe. Single-leg standing heel rise test was performed to represent the muscle function.Results
The CSA of FHL was larger in dancers (0.26 cm2 [0.20, 0.30] vs 0.21 cm2 [0.17, 0.24], p < 0.01), while other tendons were not different (all p > 0.05). Higher Vpeak was recorded in passively plantar flexion than in neutral position (p < 0.01, in both groups). The blood flow was undetectable during en pointe, more frequently in dancers (54.9% vs 14.3%, p < 0.01). Oxygen saturation decreased during en pointe more prominently in dancers (85% [80, 90] vs 94% [84, 97], p < 0.01). There was no significant difference in muscle function.Conclusions
US showed the FHL tendon thickening and en pointe-related vascular compromise in pre-professional dancers, even when they are asymptomatic. 相似文献998.
999.
1000.