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41.
The impact of comorbidity on the survival of postmenopausal women with breast cancer 总被引:5,自引:0,他引:5
Nagel G Wedding U Röhrig B Katenkamp D 《Journal of cancer research and clinical oncology》2004,130(11):664-670
Purpose The aim was to assess the impact of comorbidity on survival of postmenopausal women with breast cancer diagnosis in the period 1995–1997.Methods The level of comorbidity was described by the methods suggested by Satariano and Charlson. Coxs proportional hazard models were used to explore the impact of comorbidity on all-cause mortality.Results After a median follow-up time of 52 months, an increasing level of comorbidity was associated with a higher all-cause mortality. Compared to patients without comorbid conditions, the hazard ratio of death (HR) was 1.2 (95% CI: 0.8–1.7) for Satariano index 1 and HR 2.3 (95% CI: 1.5–3.5) for Satariano index 2, and HR 1.6 and 2.1 for the Charlson comorbidity index, respectively. Independent of comorbidity, the treatment pattern had a strong impact on survival. The level of comorbidity has an influence on the 3-year survival of postmenopausal women with breast cancer.Conclusions Long-term follow-up is required to appraise these findings in relation to treatment strategies. 相似文献
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43.
Immunologic Identification of Tissue Factor (Thromboplastin) Synthesized by Cultured Fibroblasts 总被引:2,自引:0,他引:2
The proliferative capacity of bone marrowcells from thymus-deprived nude mice wasinvestigated in lethally irradiated recipients. Although the colony-forming capacityof these cells was found to be similar tothat of normal littermates, a reduction inthe number of nucleated cells was observed in the bone marrow of nude mice.Moreover when the radioprotective effectof such cells was studied, it was foundthat 5 x 105 or 2 x 106 bone marrowcells from nude mice were less effectivein restoring hemopoiesis and establishingpermanent chimerism than similaramounts of bone marrow cells of normalcontrols. In addition, irradiated animalssurviving after injection of bone marrowcells from nude mice were found to havelower immune responses to SRBC thannormal chimeras. The possibility that mortality of irradiated recipients injected withbone marrow of nude mice is due to thepresence of a latent infective agent or ofsome inhibitory factor of hematopoiesis inthe bone marrow of such nude mice isshown to be improbable. Alternatively it issuggested that nude mice suffer from anintrinsic defect in the proliferative capacityof their bone marrow colony-forming cells(CFUs). Submitted on February 12, 1973 Revised on March 29, 1973 Accepted on April 20, 1973 相似文献
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45.
Stephanie Hiser Chi Ryang Chung Amy Toonstra Lisa Aronson Friedman Elizabeth Colantuoni Erik Hoyer Dale M. Needham 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2021,25(3):352-355
BackgroundThe Johns Hopkins Highest Level of Mobility (JH-HLM) scale is used to document the observed mobility of hospitalized patients, including those patients in the intensive care unit (ICU) setting.ObjectiveTo evaluate the inter-rater reliability of the JH-HLM, completed by physical therapists, across medical, surgical, and neurological adult ICUs at a single large academic hospital.MethodsThe JH-HLM is an ordinal scale for documenting a patient’s highest observed level of activity, ranging from lying in bed (score = 1) to ambulating >250 feet (score = 8). Eighty-one rehabilitation sessions were conducted by eight physical therapists, with 1 of 2 reference physical therapist rater simultaneously observing the session and independently scoring the JH-HLM. The intraclass correlation coefficient was used to determine the inter-rater reliability.ResultsA total of 77 (95%) of 81 assessments had perfect agreement. The overall intraclass correlation coefficient for inter-rater reliability was 0.98 (95% confidence interval: 0.96, 0.99), with similar scores in the medical, surgical, and neurological ICUs. A Bland–Altman plot revealed a mean difference in JH-HLM scoring of 0 (limits of agreement: ?0.54 to 0.61).ConclusionThe JH-HLM has excellent inter-rater reliability as part of routine physical therapy practice, across different types of adult ICUs. 相似文献
46.
Performance of Antinuclear Antibodies for Classifying Systemic Lupus Erythematosus: A Systematic Literature Review and Meta‐Regression of Diagnostic Data
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Nicolai Leuchten Annika Hoyer Ralph Brinks Monika Schoels Matthias Schneider Josef Smolen Sindhu R. Johnson David Daikh Thomas Dörner Martin Aringer George Bertsias the Systemic Lupus Erythematosus Classification Criteria Steering Committee 《Arthritis care & research》2018,70(3):428-438
Objective
To review the published literature on the performance of indirect immunofluorescence (IIF)–HEp‐2 antinuclear antibody (ANA) testing for classification of systemic lupus erythematosus (SLE).Methods
A systematic literature search was conducted in the Medline, Embase, and Cochrane databases for articles published between January 1990 and October 2015. The research question was structured according to Population, Intervention, Comparator, Outcome (PICO) format rules, and Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) recommendations were followed where appropriate. Meta‐regression analysis for diagnostic tests was performed, using the ANA titer as independent variable, while sensitivity and specificity were dependent variables.Results
Of 4,483 publications screened, 62 matched the eligibility criteria, and another 2 articles were identified through reference analysis. The included studies comprised 13,080 SLE patients in total, of whom 12,542 (95.9%) were reported to be IIF‐ANA positive at various titers. For ANA at titers of 1:40, 1:80, 1:160, and 1:320, meta‐regression gave sensitivity values of 98.4% (95% confidence interval [95% CI] 97.6–99.0%), 97.8% (95% CI 96.8–98.5%), 95.8% (95% CI 94.1–97.1%), and 86.0% (95% CI 77.0–91.9%), respectively. The corresponding specificities were 66.9% (95% CI 57.8–74.9%), 74.7% (95% CI 66.7–81.3%), 86.2% (95% CI 80.4–90.5%), and 96.6% (95% CI 93.9–98.1%), respectively.Conclusion
The results of this systematic literature review and meta‐regression confirm that IIF‐ANAs have high sensitivity for SLE. ANAs at a titer of 1:80 have sufficiently high sensitivity to be considered as an entry criterion for SLE classification criteria, i.e., formally test other classification criteria for SLE only if ANAs of at least 1:80 have been found.47.
Shear stress-induced up-regulation of the intermediate-conductance Ca(2+)-activated K(+) channel in human endothelium 总被引:3,自引:0,他引:3
Brakemeier S Kersten A Eichler I Grgic I Zakrzewicz A Hopp H Köhler R Hoyer J 《Cardiovascular research》2003,60(3):488-496
OBJECTIVE: Wall shear stress associated with blood flow is a major stimuli for generation of endothelial vasodilating and antithrombotic factors and it also regulates endothelial gene expression. Activation of endothelial intermediate-conductance Ca(2+)-activated K(+) channels (IK(Ca)) is important for the control of endothelial function by inducing cell hyperpolarization and thus generation of the endothelium-derived hyperpolarizing factor. In the present study we tested whether the IK(Ca) encoding IKCa1 gene is regulated by laminar shear stress (LSS). METHODS: Human umbilical vein endothelial cells (HUVEC) were subjected to LSS with a magnitude of 0.5-15 dyn/cm(2) and time intervals of 2-24 h in a flow cone apparatus. Expression of the IKCa1 gene and IK(Ca)-functions were determined by using real time RT-PCR and patch-clamp techniques. RESULTS: A short 2-4 h-or long 24 h-exposure to a LSS with a low (venous) magnitude of 0.5 dyn/cm(2) had no effect on IKCa1 expression levels. An exposure for 2 and 4 h to LSS with an intermediate magnitude of 5 dyn/cm(2) was also ineffective, whereas an exposure for 24 h induced a significant threefold up-regulation of IKCa1 expression levels. An exposure to LSS with a higher (arterial) magnitude of 15 dyn/cm(2), resulted in an eightfold up-regulation of IKCa1 expression levels after a 4 h-exposure and a fourfold increase of IKCa1 expression levels at 24 h. The increased IKCa1 expression levels following exposure to high levels of LSS resulted in enhanced IK(Ca) whole-cell currents and in an increased hyperpolarization of the endothelium in response to ATP and the IK(Ca) opener 1-EBIO. Inhibition of the mitogen-activated protein kinase/extracellular-signal-regulated kinase (ERK) kinase 1/2 (MEK/ERK) pathway by PD98059 prevented the LSS-induced up-regulation of IKCa1 expression levels and IK(Ca) whole-cell currents indicating that augmentation of IKCa1 expression levels is mediated by the LSS-induced activation of the MEK/ERK pathway. CONCLUSION: Long term exposure to LSS up-regulates expression and function of endothelial IK(Ca). This increase might represent a new important mechanism in endothelial adaptation to altered hemodynamics. 相似文献
48.
Moderation of hemophilia A phenotype by the factor V R506Q mutation 总被引:11,自引:1,他引:11
Nichols WC; Amano K; Cacheris PM; Figueiredo MS; Michaelides K; Schwaab R; Hoyer L; Kaufman RJ; Ginsburg D 《Blood》1996,88(4):1183-1187
Although many examples of unrelated hemophilia A patients carrying identical point mutations in the factor VIII (FVIII) gene have been reported, the clinical phenotype is not always the same among patients sharing the same molecular defect. Possible explanations for this discrepancy include undetected additional mutations in the FVIII gene or coinheritance of mutations at other genetic loci that modulate FVIII function. We report molecular genetic analysis of potential modifying genes in two sets of unrelated patients carrying common FVIII missense mutations but exhibiting different levels of clinical severity. Both mutations (FVIII R1689C and R2209Q) are associated with severe hemophilia A in some patients and mild/moderate disease in others. The common von Willebrand disease type 2N mutation (R91Q) was excluded as a modifying factor in these groups of patients. However, analysis of the recently described factor V (FV) R506Q mutation (leading to activated protein C resistance) identified a correlation of inheritance of this defect with reduced hemophilia A severity. Two moderately affected hemophilia A patients, each with either of two FVIII gene mutations, were heterozygous for FV R506Q, whereas two severely affected patients and two moderately affected patients were homozygous normal at the FV locus. Our results suggest that coinheritance of the FV R506Q mutation may be an important determinant of clinical phenotype in hemophilia A and that modification of the protein C pathway may offer a new strategy for the treatment of FVIII deficiency. 相似文献
49.
Anja K. Büscher Bodo B. Beck Anette Melk Julia Hoefele Birgitta Kranz Daniel Bamborschke Sabrina Baig B?rbel Lange-Sperandio Theresa Jungraithmayr Lutz T. Weber Markus J. Kemper Burkhard T?nshoff Peter F. Hoyer Martin Konrad Stefanie Weber 《Clinical journal of the American Society of Nephrology》2016,11(2):245-253
Background and objectives
Treatment of congenital nephrotic syndrome (CNS) and steroid–resistant nephrotic syndrome (SRNS) is demanding, and renal prognosis is poor. Numerous causative gene mutations have been identified in SRNS that affect the renal podocyte. In the era of high–throughput sequencing techniques, patients with nongenetic SRNS frequently escape the scientific interest. We here present the long-term data of the German CNS/SRNS Follow-Up Study, focusing on the response to cyclosporin A (CsA) in patients with nongenetic versus genetic disease.Design, setting, participants, & measurements
Cross–sectional and longitudinal clinical data were collected from 231 patients with CNS/SRNS treated at eight university pediatric nephrology units with a median observation time of 113 months (interquartile range, 50–178). Genotyping was performed systematically in all patients.Results
The overall mutation detection rate was high at 57% (97% in CNS and 41% in SRNS); 85% of all mutations were identified by the analysis of three single genes only (NPHS1, NPHS2, and WT1), accounting for 92% of all mutations in patients with CNS and 79% of all mutations in patients with SRNS. Remission of the disease in nongenetic SRNS was observed in 78% of patients after a median treatment period of 2.5 months; 82% of nongenetic patients responded within 6 months of therapy, and 98% of patients with nongenetic SRNS and CsA–induced complete remission (normalbuminemia and no proteinuria) maintained a normal renal function. Genetic SRNS, on the contrary, is associated with a high rate of ESRD in 66% of patients. Only 3% of patients with genetic SRNS experienced a complete remission and 16% of patients with genetic SRNS experienced a partial remission after CsA therapy.Conclusions
The efficacy of CsA is high in nonhereditary SRNS, with an excellent prognosis of renal function in the large majority of patients. CsA should be given for a minimum period of 6 months in these patients with nongenetic SRNS. In genetic SRNS, response to CsA was low and restricted to exceptional patients. 相似文献50.
Patrick Hoyer Gustavo de Medeiros Bálint Balázs Nils Norlin Christina Besir Janina Hanne Hans-Georg Kr?usslich Johann Engelhardt Steffen J. Sahl Stefan W. Hell Lars Hufnagel 《Proceedings of the National Academy of Sciences of the United States of America》2016,113(13):3442-3446
We present a plane-scanning RESOLFT [reversible saturable/switchable optical (fluorescence) transitions] light-sheet (LS) nanoscope, which fundamentally overcomes the diffraction barrier in the axial direction via confinement of the fluorescent molecular state to a sheet of subdiffraction thickness around the focal plane. To this end, reversibly switchable fluorophores located right above and below the focal plane are transferred to a nonfluorescent state at each scanning step. LS-RESOLFT nanoscopy offers wide-field 3D imaging of living biological specimens with low light dose and axial resolution far beyond the diffraction barrier. We demonstrate optical sections that are thinner by 5–12-fold compared with their conventional diffraction-limited LS analogs.Far-field nanoscopy (1, 2) methods discern features within subdiffraction distances by briefly forcing their molecules to two distinguishable states for the time period of detection. Typically, fluorophores are switched between a signaling “on” and a nonsignaling (i.e., dark) “off” state. Depending on the switching and fluorescence registration strategy used, these superresolution techniques can be categorized into coordinate-stochastic and coordinate-targeted approaches (2). The latter group of methods, comprising the so-called RESOLFT [reversible saturable/switchable optical (fluorescence) transitions] (1, 3–7) approaches, have been realized using patterns of switch-off light with one or more zero-intensity points or lines, to single out target point (zero-dimensional) or line (1D) coordinates in space where the fluorophores are allowed to assume the on state. The RESOLFT idea can also be implemented in the inverse mode, by using switch-on light and confining the off state. In any case, probing the presence of molecules in new sets of points or lines at every scanning step produces images.Owing to the nature of the on and off states involved––first excited electronic and ground state––stimulated emission depletion (STED) (3) and saturated structured illumination microscopy (SSIM) (8), which both qualify as variants of the RESOLFT principle, typically apply light intensities in the range of MW/cm2 and above. Especially when imaging sensitive samples where photoinduced changes must be avoided, RESOLFT is preferably realized with fluorophores which lead to the same factor of resolution improvement at much lower intensities of state-switching light. Reversibly switchable fluorescent proteins (RSFPs) are highly suitable for this purpose (4–7, 9), as transitions between their metastable on and off states require 5 orders of magnitude lower threshold intensities than STED/SSIM to guarantee switch-off. Suitable spectral properties, relatively fast millisecond switching kinetics, and high photostability of recently developed yellow-green-emitting RSFPs like rsEGFP (5), rsEGFP2 (7), and rsEGFP(N205S) (10) compared with early RSFPs have indeed enabled RESOLFT nanoscopy in living cells and tissues. To date, RSFP-based RESOLFT has achieved resolution improvements by factors of 4–5 in rsEGFP2-labeled samples (7). To further reduce the imaging time, massive parallelization of scanning has been reported (10). However, the diffraction-limited axial resolution and lack of background suppression restrict applications to thin samples.Imaging applications typically require careful tuning of imaging parameters including speed, contrast, photosensitivity, and spatial resolution, depending on the information that is sought. Light-sheet fluorescence microscopy (LSFM) (11–15) stands out by its ability to balance most of these parameters for 3D imaging of living specimens. Recently reenacted as the selective plane illumination microscope (13), this microscopy mode has sparked increasing interest notably because of its short acquisition times in 3D imaging and low phototoxicity in living specimens. It excites fluorophores only in a thin diffraction-limited slice of the sample, perpendicular to the direction of fluorescence detection. The LS is generated by a cylindrical lens which focuses an expanded laser beam in only one direction onto the specimen or into the back-focal plane of an illumination objective. Alternatively, a single beam is quickly moved as a “virtual” LS (16) across a specimen section.In such conventional LSFM imaging, the lateral resolution is determined by the numerical aperture (N.A.) of the detection objective (17), whereas axial resolution is given by the LS thickness, provided the latter is thinner than the axial extent of the point-spread function describing the imaging process from the focal plane of the detecting lens to the camera. In a previous study, the axial resolution of LSFM was pushed to the diffraction limit by using the full aperture of the illumination objective with Gaussian beams; this was carried out for practically useful combinations of N.A. (e.g., 0.8 for both illumination and detection objectives) permissible in light of the geometrical constraints given by the objective lens dimensions (18). High-N.A. illumination comes with short Rayleigh ranges of Gaussian beams, which inherently limit the field of view (FOV) along the direction of illumination. Scanned Bessel beams for diffraction-limited excitation with a virtual LS (19–21) typically offer larger FOVs (22), but side lobes broaden the scanned LS in the axial direction and contribute to phototoxicity outside of the focal plane of detection (20). A more complex approach has used Bessel-beam excitation in combination with structured illumination to obtain near-isotropic (but still diffraction-limited) resolution as measured on fluorescent beads (20), albeit at the cost of acquisition time and reduced contrast due to fluorescence generated by the side lobes. In different work, axial resolution has also been improved about fourfold by acquiring two complementary orthogonal views of the sample using two alternating LSs, followed by computationally fusing image information with a deconvolution incorporating both views (23). LS approaches have also helped suppress out-of-focus background for single-molecule imaging in biological situations (e.g., in ref. 24), including at superresolution (25–27).Slight axial resolution improvement beyond the diffraction barrier has been demonstrated by overlapping a Gaussian excitation LS with a STED LS featuring a zero-intensity plane (28). Due to scattering and possibly additional aberrations caused by the wavelength difference between excitation and STED light, the maximal achievable resolution in biological specimens was severely limited. This was the case even in fixed samples. A successful application of LS-STED to living cells or organisms has not been reported. The relatively high average STED laser power required for high resolution gains calls for developing a coordinate-targeted superresolution LS approach with low-power operation, meaning a concept that does not solely rely on changing the way the light is directed to––or collected from––the sample, but a concept that harnesses an “on–off” transition for improved feature separation. 相似文献