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91.

Introduction

Although the apolipoprotein E ε4-allele (APOE-ε4) is a susceptibility factor for Alzheimer's disease (AD) and dementia with Lewy bodies (DLB), its relationship with imaging and cognitive measures across the AD/DLB spectrum remains unexplored.

Methods

We studied 298 patients (AD = 250, DLB = 48; 38 autopsy-confirmed; NCT01800214) using neuropsychological testing, volumetric magnetic resonance imaging, and APOE genotyping to investigate the association of APOE-ε4 with hippocampal volume and learning/memory phenotypes, irrespective of diagnosis.

Results

Across the AD/DLB spectrum: (1) hippocampal volumes were smaller with increasing APOE-ε4 dosage (no genotype × diagnosis interaction observed), (2) learning performance as assessed by total recall scores was associated with hippocampal volumes only among APOE-ε4 carriers, and (3) APOE-ε4 carriers performed worse on long-delay free word recall.

Discussion

These findings provide evidence that APOE-ε4 is linked to hippocampal atrophy and learning/memory phenotypes across the AD/DLB spectrum, which could be useful as biomarkers of disease progression in therapeutic trials of mixed disease.  相似文献   
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BackgroundAlthough preoperative anemia has been suggested to predict postsurgical morbidity and mortality among infants < 1 year of age, the data were drawn from heterogeneous patient cohorts including severely ill infants undergoing complex, high-risk procedures. We aimed to determine whether untreated preoperative anemia was associated with increased risk of postoperative complications in infants < 1 year of age who underwent pyloromyotomy, a common and relatively simple surgery.MethodsInfants < 1 year of age undergoing pyloromyotomy were identified from the American College of Surgeons (ACS) National Surgical Quality Improvement Program-Pediatric database. Preoperative anemia was defined as a hematocrit ≤ 40% for infants 0–30 days of age and ≤ 30% for infants more than 30 days of age. Patients who received pre- or postoperative blood transfusions were excluded.ResultsWe identified 2948 patients who met our inclusion criteria, of whom 843 were anemic (29%). The overall rate of complications in this cohort was 6%. The most common postoperative complications were readmission (97 cases), surgical site infection (43), reoperation (39), prolonged hospital stay (24), urinary tract infection (3), 30-day mortality (3) and cardiac arrest (2). We found no differences in the incidence of complications in anemic versus nonanemic patients on bivariate analysis or multivariable logistic regression (adjusted odds ratio = 1.2; 95% confidence interval: 0.8–1.7; P = 0.319).ConclusionsIn relatively healthy infants undergoing pyloromyotomy, untreated preoperative anemia was not associated with postoperative compilations and should not be considered a significant risk factor.Level of evidence III.  相似文献   
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Radon inhalation decreases the level of lipid peroxide (LPO); this is attributed to the activation of antioxidative functions. This activation contributes to the beneficial effects of radon therapy, but there are no studies on the risks of radon therapy, such as DNA damage. We evaluated the effect of radon inhalation on DNA damage caused by oxidative stress and explored the underlying mechanisms. Mice were exposed to radon inhalation at concentrations of 2 or 20 kBq/m3 (for one, three, or 10 days). The 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels decreased in the brains of mice that inhaled 20 kBq/m3 radon for three days and in the kidneys of mice that inhaled 2 or 20 kBq/m3 radon for one, three or 10 days. The 8-OHdG levels in the small intestine decreased by approximately 20–40% (2 kBq/m3 for three days or 20 kBq/m3 for one, three or 10 days), but there were no significant differences in the 8-OHdG levels between mice that inhaled a sham treatment and those that inhaled radon. There was no significant change in the levels of 8-oxoguanine DNA glycosylase, which plays an important role in DNA repair. However, the level of Mn-superoxide dismutase (SOD) increased by 15–60% and 15–45% in the small intestine and kidney, respectively, following radon inhalation. These results suggest that Mn-SOD probably plays an important role in the inhibition of oxidative DNA damage.  相似文献   
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The purpose of this study was to develop ELISAs for key neural proteins, three synaptic and one glial, that exist in different intracellular compartments, which would be used as a measure of synaptic phenotype. These assays would be valuable to neurologically phenotype transgenic mouse models of human disease and also human disease itself using minimal amounts of post-mortem tissue. We showed that supernatant from crude brain tissue homogenates extracted in RIPA buffer containing 0.1% SDS bind to synaptophysin, synaptosome-associated protein of 25 kDa (SNAP-25), post-synaptic density-95 (PSD-95), and glial fibrillary acidic protein (GFAP) antibody pairs with high affinity and selectivity. Overall, RIPA + 0.1% SDS were more efficient than RIPA + 2% SDS or a buffer containing only 1% Triton-X-100. Diluting the brain extracts resulted in dose-dependent binding to the antibody pairs for each neural protein, with EC50s that varied from 8.6 μg protein for PSD-95 to 0.23 μg for GFAP. The assays were used to measure synaptic marker protein levels at various times during mouse development and GFAP in a model of disease accompanied by neuroinflammation. Comparison of ELISAs with Western blots by measuring marker levels in brain extract from developing mice showed a greater relative difference in values derived from ELISA. These ELISAs should be valuable to phenotype the synapse in neurological disease and their rodent models.  相似文献   
96.
To date, there has been little empirical evidence to support the broader use of value-based insurance design, which lowers copayments for services with high value relative to their costs. To address this lack of data, we evaluated the impact of the value-based insurance program of a US corporation, Pitney Bowes. The program eliminated copayments for cholesterol-lowering statins and reduced them for clopidogrel, a blood clot inhibitor. We found that the policy was associated with an immediate 2.8?percent increase in adherence to statins relative to controls, which was maintained for the subsequent year. For clopidogrel, the policy was associated with an immediate stabilizing of the adherence rate and a four-percentage-point difference between intervention and control subjects a year later. Our study thus provides an empirical basis for the use of this approach to improve the quality of health care.  相似文献   
97.
We examined awareness of osteoporosis prevention among peri- and post-menopausal South Asian women attending two community centers in the Dallas/Fort-Worth Metroplex. We conducted a quasi-experimental study (final N = 61) assessing knowledge about osteoporosis among South Asian women (≥40 years). The mean age was 52.3 years (SD = 8.72). Over 50% were college educated and 64% had no health insurance. We administered a baseline knowledge test, followed by a health education intervention and, 2 weeks later, by a post-test. Participants received one point for each correct answer and scores were added (≤14). Participants showed a significant increase in osteoporosis knowledge post intervention (paired t 60 = −9.5, P < .01). For example, women reported highest knowledge gains on the following: adequate calcium intake is achievable from two glasses of milk a day; very thin women are at risk for developing osteoporosis, and family history of osteoporosis is a risk factor. Intervention completers were better prepared to prevent and manage osteoporosis. Results indicate the efficacy of educational intervention in improving osteoporosis awareness; and point to the potential for knowledge acquisition aimed at developing community-based prevention strategies at the community level.  相似文献   
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The degree of exposure to pediatric and adolescent gynecology (PAG) varies across residency programs in obstetrics and gynecology and pediatrics. Nevertheless, these programs are responsible for training residents and providing opportunities within their programs to fulfill PAG learning objectives. To that end, the North American Society for Pediatric and Adolescent Gynecology has taken a leadership role in PAG resident education by creating and systematically updating the Short Curriculum. This curriculum outlines specific learning objectives that are central to PAG education and lists essential resources for learners' reference. This updated curriculum replaces the previous 2014 publication with added content, resources, and updated references. Additionally, attention to the needs of learners in pediatrics and adolescent medicine is given greater emphasis in this revised North American Society for Pediatric and Adolescent Gynecology Short Curriculum 2.0.  相似文献   
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