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Objectives

In patients with hypertrophic cardiomyopathy, obstruction of the left ventricular outflow tract can be relieved by surgical septal myectomy or alcohol septal ablation, but uncertainty remains regarding long-term results and comparative effectiveness of alcohol septal ablation. This study aims to compare short- and long-term outcomes of the 2 procedures.

Methods

Between December 1998 and September 2016, 2407 patients underwent septal myectomy and 211 patients underwent alcohol septal ablation at our institution. After 2:1 propensity score matching, the study cohort included 334 patients who underwent myectomy and 167 patients who underwent alcohol septal ablation.

Results

Median (interquartile range) ages of patients in the myectomy and alcohol septal ablation groups were 65 (58-71) years and 64 (56-73) years (P = .9), respectively. After intervention, median resting left ventricular outflow tract gradient at predischarge transthoracic echocardiography was 0 (0-10) mm Hg in the myectomy group (n = 288) and 21 (10-60) mm Hg in the alcohol septal ablation group (n = 63) (P < .001, tested at baseline gradients of 30 and 50 mm Hg). There were no differences in survival between the 2 groups (risk of death for alcohol septal ablation vs myectomy, hazard ratio, 1.5; 95% confidence interval, 0.9-2.6; P = .1). Survival of patients undergoing septal myectomy was better than that of an age-, sex-, and race-matched US population (82% vs 75% at 12 years, P = .01). Reintervention for left ventricular outflow tract obstruction was more likely to occur in patients who received alcohol septal ablation (hazard ratio, 33.3; 95% confidence interval, 4.4-250.6; P < .001).

Conclusions

There were no differences in survival of patients undergoing myectomy or alcohol septal ablation, but freedom from reintervention and early and late reduction of left ventricular outflow tract gradient are superior in patients undergoing septal myectomy.  相似文献   
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Methamphetamine is a central and peripheral nervous system stimulant. There is only a single study that describes exposure to and disposition of this compound in horses. The potential for abuse and inadvertent exposure in equine athletes along with the limited data available necessitates further study. The objectives of the current study were to describe drug and metabolite concentrations, develop an analytical method that could be used to regulate its use, and describe selected pharmacodynamic effects. In phase 1, six horses were randomized into three transmucosal dose groups (n = 2/group; 0.5, 1.0 or 10 mg). In phase 2, horses received a single 10 mg intravenous dose. In phase 3, the effects of urinary pH on elimination were studied. Blood and urine samples were collected for up to 72 hours post drug administration. Concentrations of methamphetamine were measured using liquid chromatography–tandem mass spectrometry. Methamphetamine was below the limit of detection (LOD) in blood by 2, 4, and 18 hours following transmucosal administration of 0.5, 1, and 10 mg, respectively. Following intravenous administration, methamphetamine fell below the LOD between 12 and 18 hours. Following urinary acidification, methamphetamine fell below the limit of quantitation (LOQ) by 12 hours. In urine, methamphetamine was no longer detected at 48, 48, and 72 hours in the 0.5, 1, and 10 mg transmucosal groups and 18 hours in the intravenous group. Increased urinary pH resulted in urinary concentrations of methamphetamine falling below detectable levels by 48 hours post transmucosal administration. While the number of animals was small, behavioral, stimulatory, and cardiac effects were minimal.  相似文献   
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Puberty marks the beginning of a period of dramatic physical, hormonal, and social change. This instability has made adolescence infamous as a time of “storm and stress” and it is well-established that stress during adolescence can be particularly damaging. However, prior stress may also shape the adolescent experience. In the present series of experiments, we observed sex-specific effects of early-life maternal separation stress on the timing of puberty onset in the rat. Specifically, stressed females exhibited earlier pubertal onset compared to standard-reared females, whereas stressed males matured later than their standard-reared counterparts. Further, we demonstrated that a probiotic treatment restores the normative timing of puberty onset in rodents of both sexes. These results are in keeping with previous findings that probiotics reverse stress-induced changes in learned fear behaviors and stress hormone levels, highlighting the remarkable and wide-ranging restorative effects of probiotics in the context of early-life stress.  相似文献   
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Introduction: Rural residence is associated with increased peritoneal dialysis (PD) utilization. The influence of travel distance on rates of home dialysis utilization has not been examined in the United States. The purpose of this study was to determine whether travel distances to the closest home and in-center hemodialysis (IHD) facilities are a barrier to home dialysis.♦ Methods: This was a retrospective cohort study of patients aged ≥ 18 years initiating dialysis between 2005 and 2011. Unadjusted PD and home hemodialysis (HHD) rates were compared by travel distances to both the closest home dialysis and closest IHD facilities. Adjusted PD and HHD utilization rates were examined using multivariable logistic regression models.♦ Results: There were 98,608 patients in the adjusted analyses. 55.5% of the dialysis facilities offered home dialysis. IHD, PD and HHD patients traveled median distances of 5.4, 3.5 and 6.6 miles respectively to their initial dialysis facilities. Unadjusted analyses showed an increase in PD rates and decrease in HHD rates with increased travel distances. Adjusted odds of PD and HHD were 1.6 and 1.2 respectively for a ten mile increase in distance to the closest home dialysis facility, while for distances to the closest IHD facility the odds ratios for both PD and HHD were 0.7 (all p < 0.01).♦ Conclusions: In metropolitan areas, PD and HHD generally increased with increased travel distance to the closest home dialysis facility and decreased with greater distance to an IHD facility. Examination of travel distances to PD and HHD facilities separately may provide further insight on specific barriers to these modalities which can serve as targets for future studies examining expansion of home dialysis utilization.  相似文献   
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