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61.
Time course of structural and functional maturation of human olfactory epithelial cells in vitro 下载免费PDF全文
The unique ability of olfactory neurons to regenerate in vitro has allowed their use for the study of olfactory function, regeneration, and neurodegenerative disorders; thus, characterization of their properties is important. This present study attempts to establish the timeline of structural (protein expression) and functional (odorant sensitivity) maturation of human olfactory epithelial cells (hOE) in vitro using biopsy‐derived cultured tissue. Cells were grown for 7 days; on each day, cells were tested for odorant sensitivity using calcium imaging techniques and then protein expression of each cell was tested using immunocytochemistry for proteins typically used for characterizing olfactory cells. Previous studies have shown that mature olfactory neurons in vitro attain a unique “phase‐bright” morphology and express the olfactory marker protein (OMP). By day 3 in vitro, a variety of cells were odorant‐sensitive, including both “phase‐bright” and “phase‐dark” cells that have previously been considered glial‐like cells. The functional maturation of these hOEs appears to take place within 4 days. Interestingly, the emergence of an odorant sensitivity profile of both phase‐bright and phase‐dark cells preceded the expression of marker protein expression for OMP (which is expressed only by mature neurons in vivo). This structural maturation took 5 days, suggesting that the development of odorant sensitivity is not coincident with the expression of marker molecules that are hallmarks of structural maturation. These results have important implications for the use of hOEs as in vitro models of olfactory and neuronal function. © 2013 Wiley Periodicals, Inc. 相似文献
62.
Screening for cognitive and affective dysfunction in patients suspected of mild cognitive impairment 下载免费PDF全文
63.
Targeting stathmin in prostate cancer 总被引:4,自引:0,他引:4
Stathmin is the founding member of a family of microtubule-destabilizing proteins that regulate the dynamics of microtubule polymerization and depolymerization. Stathmin is expressed at high levels in a variety of human cancers and provides an attractive molecule to target in cancer therapies that disrupt the mitotic apparatus. We developed replication-deficient bicistronic adenoviral vectors that coexpress green fluorescent protein and ribozymes that target stathmin mRNA. The therapeutic potential of these recombinant adenoviruses was tested in an experimental androgen-independent LNCaP prostate cancer model. Adenovirus-mediated transfer of anti-stathmin ribozymes resulted in efficient transduction and marked inhibition of stathmin expression in these cells. Cells that were transduced with the anti-stathmin adenoviruses showed a dramatic dose-dependent growth inhibition. This was associated with accumulation of LNCaP cells in the G2-M phases of the cell cycle. A similar dose-dependent inhibition of clonogenic potential was also observed in cells infected with anti-stathmin adenoviruses. Morphologic and biochemical analysis of infected cells showed a marked increase in apoptosis characterized by detachment of the cells, increased chromatin condensation, activation of caspase-3, and fragmentation of internucleosomal DNA. If these findings are confirmed in vivo, it may provide an effective approach for the treatment of prostate cancer. 相似文献
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66.
Catharine Chambers Shirley Chiu Allison N. Scott George Tolomiczenko Donald A. Redelmeier Wendy Levinson Stephen W. Hwang 《Community mental health journal》2014,50(5):553-559
The purpose of this study was to estimate the prevalence of mental health problems among a representative sample of homeless women with and without dependent children and determine if the effects of risk factors for mental health are modified by the presence of dependent children. Homeless women (n = 522) were recruited in 2004–2005 from shelters and meal programs in Toronto, Canada. Linear and logistic regression was performed to identify factors associated with mental health status. Poor mental health was associated with low perceived access to social support, physical/sexual assault in the past 12 months, presence of a chronic health condition, and presence of a drug use problem in the past month. Efforts to improve mental health in this population will need to address the associated problems of victimization, substance abuse, and lack of social supports. 相似文献
67.
Bas W.G. van Rhijn James W. Catto Peter J. Goebell Ruth Knüchel Shahrokh F. Shariat Henk G. van der Poel Marta Sanchez-Carbayo George N. Thalmann Bernd J. Schmitz-Dräger Lambertus A. Kiemeney 《Urologic oncology》2014,32(7):1078-1087
ObjectivesTo summarize the current status of clinicopathological and molecular markers for the prediction of recurrence or progression or both in non–muscle-invasive and survival in muscle-invasive urothelial bladder cancer, to address the reproducibility of pathology and molecular markers, and to provide directions toward implementation of molecular markers in future clinical decision making.Methods and materialsImmunohistochemistry, gene signatures, and FGFR3-based molecular grading were used as molecular examples focussing on prognostics and issues related to robustness of pathological and molecular assays.ResultsThe role of molecular markers to predict recurrence is limited, as clinical variables are currently more important. The prediction of progression and survival using molecular markers holds considerable promise. Despite a plethora of prognostic (clinical and molecular) marker studies, reproducibility of pathology and molecular assays has been understudied, and lack of reproducibility is probably the main reason that individual prediction of disease outcome is currently not reliable.ConclusionsMolecular markers are promising to predict progression and survival, but not recurrence. However, none of these are used in the daily clinical routine because of reproducibility issues. Future studies should focus on reproducibility of marker assessment and consistency of study results by incorporating scoring systems to reduce heterogeneity of reporting. This may ultimately lead to incorporation of molecular markers in clinical practice. 相似文献
68.
Kimon Bekelis Symeon Missios George Kakoulides Redi Rahmani Nathan Simmons 《The spine journal》2014,14(9):1944-1950
Background contextThere is a persistent trend for more outpatient lumbar discectomies in the United States.PurposeTo investigate the characteristics of the patients selected for ambulatory procedures.Study designRetrospective cohort study.Patient sampleForty-seven thousand one hundred twenty-five patients who underwent outpatient and 102,592 patients undergoing inpatient lumbar discectomies and were were registered in the State Ambulatory Surgery Database (SASD) and State Inpatient Database (SID), respectively, for New York, California, Florida, and North Carolina from 2005 to 2008.Outcome measuresRate of outpatient procedures, 30-day readmissions, and hospital charges.MethodsWe performed a retrospective cohort study involving patients who underwent outpatient and inpatient lumbar discectomies and were registered in SASD and SID, respectively, for New York, California, Florida, and North Carolina from 2005 to 2008. Logistic regression models were used to demonstrate the association of socioeconomic factors with the odds of undergoing an outpatient procedure.ResultsMale gender (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.03–1.08), private insurance (OR, 1.93; 95% CI, 1.86–2.01), lower Charlson Comorbidity Index (OR, 4.04; 95% CI, 3.17–5.16), and higher volume hospitals (OR, 1.06; 95% CI, 1.04–1.08) were significantly associated with outpatient procedures. Higher income (OR, 0.83; 95% CI, 0.81–0.85), older age (OR, 0.996; 95% CI, 0.995–0.997), coverage by Medicaid (OR, 0.89; 95% CI, 0.83–0.96), African Americans (OR, 0.65; 95% CI, 0.60–0.70), and other minority races were associated with decreased odds of outpatient procedures. The rate of 30-day postoperative readmissions was higher among inpatients. Institutional charges were significantly lower for outpatient lumbar discectomies. The median charge for inpatient surgery was $24,273 as compared with $11,339 for the outpatient setting (p<.0001).ConclusionsAccess to ambulatory lumbar discectomies appears to be more common for younger, white, male patients, with private insurance and less comorbidities, in the setting of higher volume hospitals. Further investigation is needed in the direction of mapping these disparities for appropriate resource utilization. 相似文献
69.
Yichen Zhong Alvaro Mu?oz George J. Schwartz Bradley A. Warady Susan L. Furth Alison G. Abraham 《Journal of the American Society of Nephrology : JASN》2014,25(5):913-917
GFR decline in patients with CKD has been widely approximated using linear models, but this linearity assumption is not well validated. We conducted a matched case-control study in children from the Chronic Kidney Disease in Children (CKiD) cohort ages 1–16 years with mild to moderate CKD to assess whether GFR decline follows a nonlinear trajectory as CKD approaches ESRD. Children (n=125) who initiated RRT (cases) during follow-up were individually matched by CKD stage at baseline and glomerular/nonglomerular diagnosis with children (n=125) who remained RRT-free when the corresponding case initiated RRT (controls). GFR trajectories were compared using log-linear and piecewise log-linear mixed effects models adjusted for baseline characteristics. From study entry to 18 months before RRT, GFR declined 7% faster among cases compared with controls. However, GFR declined 26% faster among cases compared with controls (P<0.001) during the 18 months before RRT. Nonlinearity in the rate of kidney function loss, which was shown in this cohort, may preclude accurate clinical prediction of the timing of RRT and adequate patient preparation. This study should prompt the characterization of predictive factors that may contribute to an acceleration of kidney function decline.GFR is a key measurement of kidney function, and the degree of GFR decline over time is a reflection of the severity of CKD progression. GFR decline has been approximated as linear or log-linear in most analyses of progression, an assumption that has been consistent with available data.1–4 However, many studies rely on relatively short follow-up periods and few repeated measures. Given the convenience of assuming a linear GFR trajectory, which results from the ease of modeling and interpreting linear slopes, few studies have sought to validate the linearity assumption and explore the possibility of nonlinear GFR decline. However, nonlinearity in GFR decline has been observed in some epidemiologic studies,5–7 and the implications on the risk for adverse outcomes have generated interest.8 A CKD cohort study in France found that about one half of its patients experienced nonlinear GFR decline during the last year before dialysis.5 A study by Li et al.9 used a flexible approach to model nonlinearity in GFR trajectories. Li et al.9 found evidence of nonlinear GFR trajectory behavior in adult patients with CKD, and furthermore, the probability of having nonlinear features in an individual trajectory was associated with known risk factors for CKD progression. O’Hare et al.10 found several distinct nonlinear patterns of GFR decline in the 2 years before dialysis initiation in Veterans Affairs patients.Clinical strategies and subsequent patient response to care could potentially benefit from new insights into the variable paths of progression in patients with CKD.10,11 The question of whether characterizing the nonlinearity in the GFR trajectory can assist the identification of risk groups for outcomes, such as ESRD, remains unexplored. The implications on future outcomes of an increased rate of GFR decline could inform clinical decisions about screening frequencies, treatment, or preparation for RRT.The Chronic Kidney Disease in Children (CKiD) study is an ongoing cohort study of children with CKD who, at baseline, had an eGFR between 30 and 90 ml/min per 1.73 m3 and were ages 1–16 years. An end point of the study is RRT defined as transplant or dialysis. To determine whether trajectories of GFR accelerate before RRT, we nested a case-control study, in which cases were children observed to have received RRT and controls were children with CKD who remained RRT-free at the time when the corresponding case initiated RRT.There were 147 children who experienced RRT during follow-up. Each case was matched individually to an eligible control at the time of the case occurrence. The matching factors included baseline CKD stage, glomerular/nonglomerular diagnosis, and, through design, the amount of follow-up time from study entry. Matching was done without replacement, and 22 cases were excluded from the analyses, because no appropriate control was available. We used a random sequence to determine the order of matching. The analysis was, thus, based on 125 matched case-control pairs. Demographic and clinical characteristics of cases and controls at baseline are shown in Characteristics Cases (n=125) Controls (n=125) Age, yr 12.64 (9.23–14.53) 12.33 (8.71–14.74) Sex (girls), N (%) 38 (30.4) 57 (45.6) Race (nonwhite), N (%) 51 (40.8) 36 (28.8) Urine protein/creatinine ratio 1.74 (0.48–4.04) 0.60 (0.26–1.76) Proteinuria, N (%) 0.2≤protein/creatinine ratio<2 56 (46.7) 71 (59.7) Protein/creatinine ratio≥2 51 (42.5) 23 (19.3) Baseline GFRa 32.21 (26.43–39.64) 35.77 (27.86–43.78) Glomerular diagnosis, N (%)a 47 (37.6) 47 (37.6)