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61.
62.
Szabo AN Mullen SP White SM Wojcicki TR Mailey EL Gothe N Olson EA Fanning J Kramer AF McAuley E 《Archives of physical medicine and rehabilitation》2011,92(5):785-791
Szabo AN, Mullen SP, White SM, Wojcicki TR, Mailey EL, Gothe N, Olson EA, Fanning J, Kramer AF, McAuley E. Longitudinal invariance and construct validity of the abbreviated Late-Life Function and Disability Instrument in healthy older adults.
Objective
To cross-validate the psychometric properties of the abbreviated Late-Life Function and Disability Instrument (LL-FDI), a measure of perceived functional limitations and disability.Design
Baseline and 12-month follow-up assessments conducted across the course of a 12-month exercise program.Setting
University research community.Participants
Older healthy adults (N=179; mean ± SD age, 66.43±5.67y) at baseline; 145 were retained at follow-up.Interventions
Not applicable.Main Outcome Measures
LL-FDI and functional performance measures.Results
Factor analyses confirmed the factor structure of the abbreviated LL-FDI, and all subscales met minimal criteria for temporal invariance. Significant correlations also were found between functional limitations subscales and an array of physical function performance measures, supporting the scale's construct validity.Conclusions
The abbreviated LL-FDI with some modifications appears to be temporally invariant in community-dwelling older adults. Additionally, moderate relationships between functional limitations and functional performance provide further support for these being conceptually distinct constructs. 相似文献63.
Suppression of proliferation and cardiomyocyte hypertrophy by CHAMP, a cardiac-specific RNA helicase 总被引:4,自引:0,他引:4 下载免费PDF全文
Liu ZP Olson EN 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(4):2043-2048
Adult cardiomyocytes are irreversibly postmitotic but respond to a variety of stimuli by hypertrophic growth, which is associated with an increase in cell size and protein content, organization of sarcomeres, and activation of a fetal gene program. Recently, we described a novel cardiac helicase activated by MEF2 protein (CHAMP), which is expressed specifically in the heart throughout prenatal and postnatal development. Here we show that CHAMP acts as an inhibitor of cell proliferation and cardiomyocyte hypertrophy. Ectopic expression of CHAMP inhibits proliferation of HeLa cells and blocks cell cycle entry of serum-stimulated NIH 3T3 cells. Overexpression of CHAMP in primary neonatal cardiomyocytes blocks hypertrophic growth and the induction of fetal genes in response to stimulation by serum and phenylephrine but does not prevent sarcomere organization or early mitogenic signaling events including activation of extracellular signal-regulated kinases or up-regulation of c-fos. Inhibition of cardiomyocyte hypertrophy by CHAMP requires the conserved ATPase domain and is accompanied by up-regulation of the cyclin-dependent protein kinase inhibitor p21(CIP1). These findings identify CHAMP as a cardiac-specific suppressor of cardiomyocyte hypertrophy and cell cycle progression and suggest that CHAMP may suppress these processes through the regulation of p21(CIP1). 相似文献
64.
Chylothorax in lymphangioleiomyomatosis 总被引:4,自引:0,他引:4
STUDY OBJECTIVE: Pulmonary lymphangioleiomyomatosis (LAM) is a rare, serious disorder characterized by proliferation of abnormal smooth-muscle cells and affects almost exclusively women of childbearing age. Optimal management of chylothorax, a well-recognized complication of LAM, in these patients has not been defined. This study was performed to characterize the clinical course and identify appropriate management options for chylothorax occurring in patients with LAM. DESIGN: Identification and retrospective review of available medical records on patients with LAM and chylothorax. SETTING: Tertiary-referral medical center. PATIENTS: All patients with LAM seen at Mayo Clinic, Rochester, MN, from January 1, 1976, to December 31, 2000. INTERVENTION: None. Measurement and results: Eight of 79 patients (10.1%) with LAM had chylothorax. All were women aged 33 to 51 years, and four patients had underlying tuberous sclerosis complex. These eight women represented 3.5% of the 229 patients with chylothorax seen over this 25-year period at Mayo Clinic Rochester. Six patients had unilateral pleural effusion and two patients had bilateral effusions at initial presentation. The size of the chylothorax varied and was not necessarily progressive. Management of chylothorax ranged from thoracentesis only to thoracotomy with thoracic duct ligation and parietal pleurectomy. When needed, pleurodesis by instillation of sclerosing agents or parietal pleurectomy appeared to be effective in controlling chylothorax. CONCLUSIONS: Chylothorax occurring in patients with LAM has a variable clinical course. Although pleurodesis with or without thoracic duct ligation appears to be effective in controlling intractable chylothorax, less invasive treatments such as thoracentesis or observation may suffice in some cases. Management of chylothorax in patients with LAM should be individualized depending on the size and clinical effects of the chylous pleural effusion, as well as comorbid factors and local expertise. 相似文献
65.
Geno J. Merli Judd E. Hollander Patrick Lefebvre Monika K. Raut William H. Olson 《Hospital practice (1995)》2015,43(2):85-93
Background. Compared to warfarin, the non-vitamin K antagonist oral anticoagulant rivaroxaban may have advantages in treating patients with venous thromboembolism, because injectable bridging therapy and routine laboratory monitoring are not required. The objective of this study was to compare the rate of hospitalization in patients treated with rivaroxaban after its introduction with what it would have been before the introduction of rivaroxaban. Methods. A retrospective claims analysis was conducted using the MarketScan Hospital Drug Database from January 2011 to December 2013. Adult patients with a primary diagnosis of deep vein thrombosis (DVT) treated with rivaroxaban or low-molecular-weight heparin (LMWH) bridged to warfarin during the first day of an evaluation at a hospital were identified. Based on propensity-score methods, historical LMWH/warfarin patients (i.e., patients who received LMWH/warfarin before the approval of rivaroxaban) were matched 4:1 to rivaroxaban patients, and the rates of hospitalization were compared. Results. All rivaroxaban-treated patients (n = 134) in the database were well matched with four historical LMWH/warfarin-treated patients (n = 536). Among the rivaroxaban cohort, 60% of the patients were admitted to the hospital, compared to 82% of the historical patients treated with LMWH/warfarin in the matched cohort. The difference was statistically significant and corresponded to a 27% reduction in hospital admissions (rate ratio [95% confidence interval]: 0.73 [0.62–0.84]). Hospital admission rates adjusted for time-trend analyses also led to similar results. Conclusion. The availability of rivaroxaban significantly reduced the hospitalization rate in patients with DVT treated with rivaroxaban compared to what it would have been if only LMWH/warfarin were available. 相似文献
66.
Eui Young So Mutsuko Ouchi Sara Cuesta-Sancho Susan Losee Olson Dirk Reif Kazuhiro Shimomura Toru Ouchi 《Cancer biology & therapy》2015,16(3):460-465
Resistant maltodextrin Fibersol-2 is a soluble and fermentable dietary fiber that is Generally Recognized As Safe (GRAS) in the United States. We tested whether Fibersol-2 contains anti-tumor activity. Human colorectal cancer cell line, HCT116, and its isogenic cells were treated with FIbersol-2. Tumor growth and tumorigenesis were studied in vitro and in vivo. Apoptotic pathway and generation of reactive oxygen species (ROS) were investigated. We discovered that Fibersol-2 significantly inhibits tumor growth of HCT116 cells by inducing apoptosis. Fibersol-2 strongly induces mitochondrial ROS and Bax-dependent cleavage of caspase 3 and 9, which is shown by isogenic HCT116 variants. Fibersol-2 induces phosphorylation of Akt, mTOR in parental HCT116 cells, but not in HCT116 deficient for Bax or p53. It prevents growth of tumor xenograft without any apparent signs of toxicity in vivo. These results identify Fibersol-2 as a mechanism-based dietary supplement agent that could prevent colorectal cancer development. 相似文献
67.
68.
H P Yang L S Cook E Weiderpass H-O Adami K E Anderson H Cai J R Cerhan T V Clendenen A S Felix C M Friedenreich M Garcia-Closas M T Goodman X Liang J Lissowska L Lu A M Magliocco S E McCann K B Moysich S H Olson S Petruzella M C Pike S Polidoro F Ricceri H A Risch C Sacerdote V W Setiawan X O Shu A B Spurdle B Trabert P M Webb N Wentzensen Y-B Xiang Y Xu H Yu A Zeleniuch-Jacquotte L A Brinton 《British journal of cancer》2015,112(5):925-933
Background:
Nulliparity is an endometrial cancer risk factor, but whether or not this association is due to infertility is unclear. Although there are many underlying infertility causes, few studies have assessed risk relations by specific causes.Methods:
We conducted a pooled analysis of 8153 cases and 11 713 controls from 2 cohort and 12 case-control studies. All studies provided self-reported infertility and its causes, except for one study that relied on data from national registries. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI).Results:
Nulliparous women had an elevated endometrial cancer risk compared with parous women, even after adjusting for infertility (OR=1.76; 95% CI: 1.59–1.94). Women who reported infertility had an increased risk compared with those without infertility concerns, even after adjusting for nulliparity (OR=1.22; 95% CI: 1.13–1.33). Among women who reported infertility, none of the individual infertility causes were substantially related to endometrial cancer.Conclusions:
Based on mainly self-reported infertility data that used study-specific definitions of infertility, nulliparity and infertility appeared to independently contribute to endometrial cancer risk. Understanding residual endometrial cancer risk related to infertility, its causes and its treatments may benefit from large studies involving detailed data on various infertility parameters. 相似文献69.
Jacqueline AM Smith DL Patil OT Daniels Y-S Ding J-D Gallezot S Henry KHS Kim S Kshirsagar WJ Martin GP Obedencio E Stangeland PR Tsuruda W Williams RE Carson ST Patil 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(2)
Background:
Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.Methods:
We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.Results:
TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.Conclusions:
These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation. 相似文献70.
D. A. Wiles J. L. Russell K. R. Olson P. D. Walson M. Kelley 《Journal of medical toxicology》2015,11(1):106-109