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51.
For decades, hematopoietic stem cells (HSCs) were thought to be a homogeneous population of cells with flexible behavior. Now a new picture has emerged: The HSC compartment consists of several subpopulations of HSCs each with distinct, preprogrammed differentiation and proliferation behaviors. These programs are epigenetically fixed and are stably bequeathed to all daughter HSCs on self-renewal. HSCs within each subset are remarkably similar in their self- renewal and differentiation behaviors, to the point where their life span can be predicted with mathematical certainty. Three subsets can be distinguished when HSCs are classified by their differentiation capacity: myeloid-biased, balanced, and lymphoid-biased HSCs. The relative number of the HSC subsets is developmentally regulated. Lymphoid-biased HSCs are found predominantly early in the life of an organism, whereas myeloid-biased HSCs accumulate in aged mice and humans. Thus, the discovery of distinct subpopulations of HSCs has led to a new understanding of HCS aging. This finding has implications for other aspects of HSC biology and applications in re-generative medicine. The possibility that other adult tissue stem cells show similar heterogeneity and mechanisms of aging is discussed. 相似文献
52.
M Reincke E Fischer S Gerum K Merkle S Schulz A Pallauf M Quinkler G Hanslik K Lang S Hahner B Allolio C Meisinger R Holle F Beuschlein M Bidlingmaier S Endres;Participants of the German Conn's Registry-Else Kröner-Fresenius-Hyperaldosteronism Registry 《Hypertension》2012,60(3):618-624
In comparison with essential hypertension, primary aldosteronism (PA) is associated with an increased risk of cardiovascular morbidity. To date, no data on mortality have been published. We assessed mortality of patients treated for PA within the German Conn's registry and identified risk factors for adverse outcome in a case-control study. Patients with confirmed PA treated in 3 university centers in Germany since 1994 were included in the analysis. All of the patients were contacted in 2009 and 2010 to verify life status. Subjects from the population-based F3 survey of the Cooperative Health Research in the Region of Augsburg served as controls. Final analyses were based on 600 normotensive controls, 600 hypertensive controls, and 300 patients with PA. Kaplan-Meyer survival curves were calculated for both cohorts. Ten-year overall survival was 95% in normotensive controls, 90% in hypertensive controls, and 90% in patients with PA (P value not significant). In multivariate analysis, age (hazard ratio, 1.09 per year [95% CI, 1.03-1.14]), angina pectoris (hazard ratio, 3.6 [95% CI, 1.04-12.04]), and diabetes mellitus (hazard ratio, 2.55 [95% CI, 1.07-6.09]) were associated with an increase in all-cause mortality, whereas hypokalemia (hazard ratio, 0.41 per mmol/L [95% CI, 0.17-0.99]) was associated with reduced mortality. Cardiovascular mortality was the main cause of death in PA (50% versus 34% in hypertensive controls; P<0.05). These data indicate that cardiovascular mortality is increased in patients treated for PA, whereas all-cause mortality is not different from matched hypertensive controls. 相似文献
53.
Lutz Philipp Breitling Heiko Müller Christa Stegmaier Matthias Kliegel Hermann Brenner 《Experimental gerontology》2012
Objectives
Recent animal studies have suggested a key role for cellular prion protein (PrPc) in the pathological consequences of amyloid plaque formation, the hallmark of Alzheimer's disease. This epidemiological study investigated whether serum concentrations of PrPc are associated with cognitive functioning in humans.Design, Setting, Participants
Cross-sectional study of 1,322 participants from the elderly general population in Germany, aged 65 + years at baseline (2000–2002).Measurements
Cognitive functioning was assessed by the COGTEL phone interview 5 years after baseline. Serum PrPc was determined by a commercial immunoassay.Results
In multiple linear regression adjusted for important confounders, subjects in higher PrPc quintiles appeared to have lower cognitive functioning scores than those in the lowest PrPc quintile. Spline regression suggested pronounced non-linearity with an inverse association between PrPc and cognitive functioning levelling off beyond median PrPc. Cognitive subdomain-specific models produced somewhat heterogeneous results.Conclusion
The findings are suggestive of an independent association of PrPc with cognitive functioning in humans. Confirmatory and longitudinal studies are needed to elucidate the potential of PrPc for applications in early risk stratification for cognitive impairment. 相似文献54.
Elisabeth V.C. Friedrich Reinhold Scherer Christa Neuper 《Clinical neurophysiology》2013,124(1):61-69
ObjectiveThe aim of this study was to examine the temporal stability of event-related desynchronization/synchronization (ERD/S) patterns over several sessions as a function of mental task, frequency band, brain region and time interval during the imagery period.MethodsNine volunteers participated in four sessions within 2 weeks of multi-channel EEG recordings. They performed seven mental tasks (i.e. mental rotation, word association, auditory imagery, mental subtraction, spatial navigation, imagery of familiar faces, motor imagery) during 7-s imagery periods. Cronbach’s alpha coefficients were calculated over sessions to evaluate the stability of ERD/S values.ResultsThe word association, mental subtraction and spatial navigation task showed highest stability. Cronbach’s alpha coefficients were highest in the alpha bands (7–10, 10–13 Hz), poorer in the beta bands (13–20, 20–30 Hz) and poorest in the theta band (4–7 Hz). In the majority of tasks, the first time interval and posterior left regions showed highest stability and strongest ERD in the alpha and beta bands.ConclusionStability of ERD/S is strongly dependent on the specific task and differs between time intervals of the imagery period. Furthermore, stability was related to ERD in the alpha and beta bands.SignificanceThe reliability of brain activation patterns is highly relevant for brain–computer interface developments. 相似文献
55.
56.
Hunger M Schunk M Meisinger C Peters A Holle R 《Journal of diabetes and its complications》2012,26(5):413-418
ObjectivesObesity is known to be an important risk factor for type 2 diabetes and its related comorbid conditions; however, its specific impact on generic health-related quality of life (HRQL) is less clear. The objective of this study was to estimate the association between body mass index (BMI) and HRQL in individuals with type 2 diabetes.MethodsThe EQ-5D quality of life questionnaire was administered in a follow-up of 10,385 participants aged 33–94 of the population-based German MONICA/KORA surveys. 1033 participants with type 2 diabetes were identified by self-report combined with validated physician diagnoses. Semiparametric additive regression models were used to estimate the effect of BMI on EQ-5D health utilities adjusted for age, sex, education and comorbidities.ResultsBMI was significantly associated with EQ-5D health utilities even after adjustment for macro- and microvascular complications. The functional relationship between BMI and utilities was nonlinear, reflecting optimal health around 26 kg/m2 and significantly decreasing health utilities with increasing levels of overweight and obesity (? 0.09 points between BMI values 26 and 40). Among the diabetic complications, the history of a stroke (? 0.13) and neuropathy (? 0.10) were the strongest predictors of reduced health utility scores.ConclusionsBMI is strongly associated with health utilities in persons with type 2 diabetes. This suggests that lifestyle measures to reduce obesity can markedly improve patients' health-related quality of life and that the negative effect of potential weight gain should be taken into account when determining patient preferences for different type 2 diabetes treatment options. 相似文献
57.
Petersen HH Larsen MC Nielsen OW Kensing F Svendsen JH 《Journal of interventional cardiac electrophysiology》2012,34(3):317-324
Purpose
The study aim was to evaluate patient acceptance and content with remote follow-up (FU) of their implantable cardioverter defibrillator (ICD) and to estimate patients?? wish for changes in remote follow-up routines.Methods
Four hundred seventy-four ICD patients at the device follow-up clinic at Rigshospitalet using CareLink? (Medtronic) remote follow-up, who had made ??2 transmissions, received a questionnaire.Results
Three hundred eighty-five patients (81.2%) answered. Mean time with ICD was 56?±?45?months and mean age was 62?±?13?years; 80% was male. Diagnosis related to ICD implant was: ischemic heart disease in 56% and dilated cardiomyopathy in 21%. Twenty-six percent had primary prophylactic indication. Mean time on remote FU was 16.4?±?6.9?months. Mean time spent on in-clinic FU (two-way transport and FU) was 4?h and 36?min?±?7?h and 50?min, excluding 12 patients from Greenland and Faroe Islands. Ninety-five percent of the patients was very content or content with remote FU compared to in-clinic FU; 3% was less content and 2% was not content. For scheduled transmissions, 21% of the patients wished for a faster reply (sms or e-mail) compared to current practice with a letter. Eighty-four percent preferred more detailed information concerning ICD leads, battery status, and ICD therapies. A total of 96 patients (25%) had performed extra unscheduled remote transmissions: 20 due to shock, 20 due to alarm, 35 due to palpitations, and 18 for other or combined reasons.Conclusion
Ninety-five percent of the patients were content with the remote FU. Only 25% had unscheduled transmissions and most unscheduled transmissions were for appropriate reasons. Eighty-four percent of the patients wished for a more detailed response and 21% wished for a faster reply after routine transmissions. 相似文献58.
Christa?Kasang Albrecht?Ulmer Norbert?Donhauser Barbara?Schmidt August?Stich Hartwig?Klinker Samuel?Kalluvya Eleni?Koutsilieri Axel?Rethwilm Carsten?SchellerEmail author 《BMC infectious diseases》2012,12(1):14
Background
HIV-associated general immune activation is a strong predictor for HIV disease progression, suggesting that chronic immune activation may drive HIV pathogenesis. Consequently, immunomodulating agents may decelerate HIV disease progression. 相似文献59.
Abstract The aim of this study was to identify personality factors predicting psychotherapy utilization on the basis of personality pathology, affect regulation and interpersonal functioning. The authors assessed affectivity (using the Affect Experience and Affect Regulation Q-Sort), interpersonal context (using the Quality of Object Relations Scale), and character pathology (using the Shedler–Westen Assessment Procedure-200). Combination of instruments showed one stable factor predictive for nonengagement in psychotherapy, revealing an externalizing personality dimension, dominated by externalizing defenses, acting out, deficient superego functions, and impairment in reflective functioning and in relating to others. Stability of the predictive power of this personality factor for therapy engagement could be shown, and replication in two other samples confirmed the findings. The results highlight the importance of measuring affect-regulatory mechanisms, and clinical implications for intervention techniques are discussed. 相似文献
60.
Katrin D. Bartl-Pokorny Peter B. Marschik Jeff Sigafoos Helen Tager-Flusberg Walter E. Kaufmann Tobias Grossmann Christa Einspieler 《Research in developmental disabilities》2013,34(10):3133-3138
Rett syndrome (RTT) is a severe neurological disorder characterized by a developmental regression in motor and speech-language domains. There is, however, limited research on socio-communicative development of affected children before the onset of regression. We analyzed audio–video recordings made by parents of six 9- to 12-month old girls later diagnosed with typical RTT, applying the Inventory of Potential Communicative Acts (IPCA) to identify early communicative forms and functions. Each girl used at least one communicative form (e.g., body movement, eye gaze, or vocalizations) to gain attention and answer, but none were observed to make choices or request information. Varying numbers of children were observed to perform other communicative functions according to the IPCA including social convention, rejecting or requesting an object. Non-verbal forms (e.g., reaching, moving closer, eye contact, smiling) were more common than non-linguistic verbal forms (e.g., unspecified vocalizations, pleasure vocalizations, crying). (Pre-)linguistic verbal forms (e.g., canonical or variegated babbling, proto-words) were not used for communicative purposes. These data suggest that atypical developmental patterns in the socio-communicative domain are evident prior to regression in young individuals later diagnosed with RTT. 相似文献