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981.
982.
Martina Absinta Pascal Sati Matthew Schindler Emily C. Leibovitch Joan Ohayon Tianxia Wu Alessandro Meani Massimo Filippi Steven Jacobson Irene C.M. Cortese Daniel S. Reich 《The Journal of clinical investigation》2016,126(7):2597-2609
BACKGROUND. In some active multiple sclerosis (MS) lesions, a strong immune reaction at the lesion edge may contain growth and thereby isolate the lesion from the surrounding parenchyma. Our previous studies suggest that this process involves opening of the blood-brain barrier in capillaries at the lesion edge, seen on MRI as centripetal contrast enhancement and a colocalized phase rim. We hypothesized that using these features to characterize early lesion evolution will allow in vivo tracking of tissue degeneration and/or repair, thus improving the evaluation of potential therapies for chronic active lesions.METHODS. Centripetally and centrifugally enhancing lesions were studied in 17 patients with MS using 7-tesla MRI. High-resolution, susceptibility-weighted, T1-weighted (before/after gadolinium), and dynamic contrast–enhanced scans were acquired at baseline and months 1, 3, 6, and 12. For each lesion, time evolution of the phase rim, lesion volume, and T1 hypointensity were assessed. In autopsies of 3 progressive MS cases, the histopathology of the phase rim was determined.RESULTS. In centripetal lesions, a phase rim colocalized with initial contrast enhancement. In 12 of 22, this phase rim persisted after enhancement resolved. Compared with centripetal lesions with transient rim, those with persistent rim had less volume shrinkage and became more T1 hypointense between months 3 and 12. No centrifugal lesions developed phase rims at any time point. Pathologically, persistent rims corresponded to an iron-laden inflammatory myeloid cell population at the edge of chronic demyelinated lesions.CONCLUSION. In early lesion evolution, a persistent phase rim in lesions that shrink least and become more T1 hypointense over time suggests that the rim might mark failure of early lesion repair and/or irreversible tissue damage. In later stages of MS, phase rim lesions continue to smolder, exerting detrimental effects on affected brain tissue.TRIAL REGISTRATION. .FUNDING. The Intramural Research Program of NINDS supported this study. NCT00001248相似文献
983.
Roorda LD Roebroeck ME van Tilburg T Molenaar IW Lankhorst GJ Bouter LM Boonstra AM de Laat FA Caron JJ Burger BJ Heyligers IC Nollet F Stover-Van Herk IE Perez RS Meijer JW Rijken PM;Measuring Mobility Study Group 《Archives of physical medicine and rehabilitation》2005,86(12):1396-2283
OBJECTIVE: To develop a hierarchical scale that measures activity limitations in walking in patients with lower-extremity disorders who live at home. DESIGN: Cross-sectional study. SETTING: Orthopedic workshops and outpatient clinics of secondary and tertiary care centers. PARTICIPANTS: Patients (N=981; mean age +/- standard deviation, 58.6+/-15.4 y; 46% men) living at home, with different lower-extremity disorders: stroke, poliomyelitis, osteoarthritis, amputation, complex regional pain syndrome type I, and diabetic and degenerative foot disorders. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: (1) Fit of the monotone homogeneity model, indicating whether items can be used for measuring patients; (2) fit of the double monotonicity model, indicating invariant (hierarchical) item ordering; (3) intratest reliability, indicating repeatability of the sum score; (4) robustness, addressing the clinimetric properties within subgroups of patients; and (5) differential item functioning, addressing the validity of comparisons between subgroups of patients. RESULTS: Thirty-five of 41 dichotomous items had (1) good fit of the monotone homogeneity model (coefficient H=.50), (2) good fit of the double monotonicity model (coefficient H(T)=.33), (3) good intratest reliability (coefficient rho=.95), (4) satisfactory robustness (within subgroups of patients defined by age, sex, and diagnosis), and (5) some differential item functioning (6 items in amputees compared with nonamputees). CONCLUSIONS: A hierarchical scale, with excellent scaling characteristics, was developed to measure activity limitations in walking in patients with lower-extremity disorders who live at home. The measurements should be interpreted cautiously when making comparisons between amputees and nonamputees. 相似文献
984.
Study protocol: The DOse REsponse Multicentre International collaborative initiative (DO-RE-MI) 下载免费PDF全文
Kindgen-Milles D Journois D Fumagalli R Vesconi S Maynar J Marinho A Bolgan I Brendolan A Formica M Livigni S Maio M Marchesi M Mariano F Monti G Moretti E Silengo D Ronco C 《Critical care (London, England)》2005,9(4):R396-R406
Introduction
Current practices for renal replacement therapy in intensive care units (ICUs) remain poorly defined. The DOse REsponse Multicentre International collaborative initiative (DO-RE-MI) will address the issue of how the different modes of renal replacement therapy are currently chosen and performed. Here, we describe the study protocol, which was approved by the Scientific and Steering Committees.Methods
DO-RE-MI is an observational, multicentre study conducted in ICUs. The primary end-point will be the delivered dose of dialysis, which will be compared with ICU mortality, 28-day mortality, hospital mortality, ICU length of stay and number of days of mechanical ventilation. The secondary end-point will be the haemodynamic response to renal replacement therapy, expressed as percentage reduction in noradrenaline (norepinephrine) requirement. Based on the the sample analysis calculation, at least 162 patients must be recruited. Anonymized patient data will be entered online in electronic case report forms and uploaded to an internet website. Each participating centre will have 2 months to become acquainted with the electronic case report forms. After this period official recruitment will begin. Patient data belong to the respective centre, which may use the database for its own needs. However, all centres have agreed to participate in a joint effort to achieve the sample size needed for statistical analysis.Conclusion
The study will hopefully help to collect useful information on the current practice of renal replacement therapy in ICUs. It will also provide a centre-based collection of data that will be useful for monitoring all aspects of extracorporeal support, such as incidence, frequency, and duration. 相似文献985.
986.
987.
Concentration of Myo-inositol in Skeletal Muscle of the Rat Occurs without Active Transport 总被引:2,自引:2,他引:2 下载免费PDF全文
Bruce A. Molitoris Irene E. Karl William H. Daughaday 《The Journal of clinical investigation》1980,65(4):783-788
The cellular uptake of nonphosphorylated myo-inositol (MI) and its incorporation into phosphoinositide in the rat epitrochlearis muscle was measured. Cellular uptake of [2-3H]MI was determined by the difference between total uptake and [2-3H]MI present in the extracellular fluid determined with [1-14C]mannitol. Cellular uptake was parabolic and directly proportional to medium MI concentrations between 25 and 3,200 μM. Saturation of a MI carrier was not evident. Moreover, uptake was not inhibited by 2 mM ouabain, 0.3 mM 2,4-dinitrophenol, or 22 mM glucose. Insulin, 100 mU/ml, was without effect on either cellular uptake of [2-3H]MI or its incorporation into phosphoinositides. In muscles that were preloaded with [2-3H]MI and then incubated in media that contained a constant amount of MI but no [2-3H]MI, 44.3% of the [2-3H]MI was released after 10 min increasing to 62.5% by 120 min. Cellular MI concentrations were 0.18 μmol/g wet tissue (four times plasma levels) in rapidly isolated and frozen epitrochlearis muscle. When muscle was incubated without MI, 48% of endogenous MI was lost rapidly. Restoration of cellular MI in 50 μM MI media occurred in two phases, a rapid uptake phase lasting 10 min and a subsequent slow phase of MI uptake. 相似文献
988.
Tuffrey-Wijne I 《International journal of palliative nursing》2002,8(5):222-232
This article describes a case study that aimed to consider the unique needs of a client who has intellectual disabilities and a terminal illness. Data collection included semi-structured interviews with the client and professionals involved in his care. Five broad sets of themes emerged from these interviews. Although these are not unique to the rapidly evolving field of palliative care, they are less familiar within the specialism of intellectual disabilities, i.e. difficulties and delays around diagnosing the illness, consent issues, conflicts between the carers and the family, truth-telling, and the need for professional support. Professionals who work with a person with intellectual disabilities and a terminal illness need to be aware that special issues may arise. The effects of potential problems with comprehension and communication need to be assessed individually. A close collaboration between all professionals, carers, family and the client, and the mutual sharing of expertise, is essential to ensure the best possible care. 相似文献
989.
990.