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61.
Access to kidney transplantation in European adults aged 75–84 years and related outcomes: an analysis of the European Renal Association–European Dialysis and Transplant Association Registry 下载免费PDF全文
Maria Pippias Vianda S. Stel Anneke Kramer Jose M. Abad Diez Nuria Aresté‐Fosalba Carole Ayav Jadranka Buturovic Fergus J. Caskey Frederic Collart Cécile Couchoud Johan De Meester James G. Heaf Ilkka Helanterä Marc H. Hemmelder Myrto Kostopoulou Marlies Noordzij Julio Pascual Runolfur Palsson Anna Varberg Reisæter Jamie P. Traynor Ziad Massy Kitty J. Jager 《Transplant international》2018,31(5):540-553
To what extent access to, and allocation of kidney transplants and survival outcomes in patients aged ≥75 years have changed over time in Europe is unclear. We included patients aged ≥75–84 years (termed older adults) receiving renal replacement therapy in thirteen European countries between 2005 and 2014. Country differences and time trends in access to, and allocation of kidney transplants were examined. Survival outcomes were determined by Cox regression analyses. Between 2005 and 2014, 1392 older adult patients received 1406 transplants. Access to kidney transplantation varied from ~0% (Slovenia, Greece and Denmark) to ~4% (Norway and various Spanish regions) of all older adult dialysis patients, and overall increased from 0.3% (2005) to 0.9% (2014). Allocation of kidney transplants to older adults overall increased from 0.8% (2005) to 3.2% (2014). Seven‐year unadjusted patient and graft survival probabilities were 49.1% (95% confidence interval, 95% CI: 43.6; 54.4) and 41.7% (95% CI: 36.5; 46.8), respectively, with a temporal trend towards improved survival outcomes. In conclusion, in the European dialysis population aged ≥75–84 years access to kidney transplantation is low, and allocation of kidney transplants remains a rare event. Though both are increasing with time and vary considerably between countries. The trend towards improved survival outcomes is encouraging. This information can aid informed decision‐making regarding treatment options. 相似文献
62.
Differentiation of breast masses using 3-D sonographic and echo-enhancer-based evaluation of the vascular pattern: initial experiences 总被引:2,自引:0,他引:2
Hochmuth A Boehm T Bitzer C Fleck M Schneider A Kaiser WA 《Ultrasound in medicine & biology》2002,28(7):845-851
To evaluate the potential of combined 3-D B-mode and color Doppler (CD) data sets in the differentiation of breast masses, in 50 patients with histologically proven solid breast lesions, 3-D datasets were acquired. A 3-D display was created and volume calculation of tumors, their periphery and vasculature was performed. Time-intensity curves of enhancement after administration of a contrast agent were analyzed. Volumetry of tumor vasculature yielded no significant differences between malignant and benign tumors regarding vascularization of the center (2.60 vs. 2.88%) and periphery (6.66 vs. 3.78%). Only the mean values for the rise time in the center of the tumor, fibroadenoma (FA): 5.7 s and ductal invasive carcinoma (DIC): 15.8s; p = 0.05, and the time to peak in the periphery, FA: 21.0 s and DIC: 31.6 s; p = 0.03, differed significantly. The 3-D ultrasound (US) technique was of no additional value in differentiating breast masses. The calculation of time-intensity curves after administration of a contrast agent may be helpful in differentiating FA and DIC. 相似文献
63.
Iris Noordman Anthonie Duijnhouwer Livia Kapusta Marlies Kempers Nel Roeleveld Michiel Schokking Dominique Smeets Kim Freriks Henri Timmers Janiëlle van Alfen-van der Velden 《European journal of medical genetics》2018,61(6):301-306
Introduction
Turner syndrome (TS) is a genetic disorder characterized by the (partial) absence or a structural aberration of the second sex chromosome and is associated with a variety of phenotypes with specific physical features and cardio-aortic malformations. The objective of this study was to gain a better insight into the differences in dysmorphic features between girls and women with TS and to explore the association between these features, karyotype and cardio-aortic malformations.Methods
This prospective study investigated 14 dysmorphic features of TS girls and women using a checklist. Three major phenotypic patterns were recognized (severe phenotype, lymphatic phenotype and skeletal phenotype). Patient data including karyotype and cardio-aortic malformations (bicuspid aortic valve (BAV) and aortic coarctation (COA)) were collected. Associations between the prevalence of dysmorphic features, karyotype and cardio-aortic malformations were analysed using chi2-test and odds ratios.Results
A total of 202 patients (84 girls and 118 women) were analysed prospectively. Differences in prevalence of dysmorphic features were found between girls and women. A strong association was found between monosomy 45,X and the phenotypic patterns. Furthermore, an association was found between COA and lymphatic phenotype, but no association was found between karyotype and cardio-aortic malformations.Conclusion
This study uncovered a difference in dysmorphic features between girls and women. Monosomy 45,X is associated with a more severe phenotype, lymphatic phenotype and skeletal phenotype. All patients with TS should be screened for cardio-aortic malformations, because in contrast to previous reports, karyotype and cardio-aortic malformations showed no significant association. 相似文献64.
65.
I Bekaert J L Pannier C Van de Weghe J P Van Durme D L Clement R Pannier 《Heart (British Cardiac Society)》1981,45(2):213-218
Cardiac dimensions and left ventricular function were investigated at rest with non-invasive methods in 14 professional road race cyclists and in 11 age-matched sedentary control subjects. The electrocardiographic findings were in agreement with previous studies in endurance athletes and the vectocardiographic data showed anterior displacement of the electrical forces. Echocardiographic dimensions at end-diastole showed higher values in the cyclists for left ventricular internal diameter, left ventricular posterior wall thickness, and interventricular septal thickness. Derived values for left ventricular volume and left ventricular mass were also much larger in the cyclists and there was excellent agreement between total heart volume measured with radiology and total measured by echocardiography. There was a significant correlation between maximal oxygen consumption and end-diastolic left ventricular diameter. 相似文献
66.
Bernt van den Blink Marlies S. Wijsenbeek Henk C. Hoogsteden 《Pulmonary pharmacology & therapeutics》2010,23(6):515-520
Within the group of Idiopathic Interstitial Pneumonias (IIPs), above all Idiopathic Pulmonary Fibrosis (IPF) poses a considerable diagnostic and therapeutic problem. Although genetic profiling indicates that IPF, Non Specific Interstitial Pneumonia (NSIP), and chronic hypersensitivity pneumonitis (HP) are distinctly different diseases, in every day practice these diseases can be difficult to tell apart. Furthermore, treatment of these diseases is notoriously difficult. Serum biomarkers reflect our understanding of the underlying pathogenesis and potentially fulfill a role in establishing a diagnosis, prognosis and therapy. While no single biomarker is currently able to accurately predict the presence or absence of an IIP, a composite of several markers holds promise for the future. Several biomarkers, such as KL-6, surfactant proteins and circulating fibrocytes, appear to contribute to our insight into disease progression and prognosis. It is however uncertain whether these markers give us additional information to common diagnostic tests and their value has as yet to be validated for every day practice. Fortunately, the potential of biomarkers is increasingly recognized and biomarker data are prospectively gathered in current placebo-controlled therapeutic trials. 相似文献
67.
Avlasevich S Bryce S De Boeck M Elhajouji A Van Goethem F Lynch A Nicolette J Shi J Dertinger S 《Mutagenesis》2011,26(1):147-152
The relative simplicity of the in vitro micronucleus (MNvit) endpoint has made it amenable to several automated scoring approaches. Flow cytometry is one such scoring platform that has been successfully employed. This review describes the origins of the MNvit assay, as well as the evolution and properties of flow cytometry-based scoring systems. While the current state-of-the-art methods acquire micronucleus (MN) frequency data very efficiently, it is becoming clear that they also endow the assay with high information content. For instance, simultaneous with MN frequency determinations, several additional endpoints are acquired that provide insights into cytotoxicity, cell cycle perturbations and, in the event of MN induction, information about genotoxic mode of action. This review concludes with a discussion regarding data gaps and also recommendations for additional work that is needed to more fully realise the potential of flow cytometric MNvit scoring. 相似文献
68.
Somers K Geusens P Elewaut D De Keyser F Rummens JL Coenen M Blom M Stinissen P Somers V 《Journal of autoimmunity》2011,36(1):33-46
Approximately one-third of rheumatoid arthritis (RA) patients are seronegative for the 2 serological RA markers, rheumatoid factor (RF) and antibodies against cyclic citrullinated peptides (ACCP). Moreover, the sensitivities of both markers are lower in the diagnostically important early disease phase. The aim of this study was to identify additional autoantibody markers for early RA and for RF-negative, ACCP-negative (seronegative) RA.We screened an RA synovium cDNA phage display library with autoantibodies in plasma from 10 early (symptoms of maximum 1 year) and 10 seronegative (RF-negative, ACCP-negative) RA patients with validation in 72 additional RA patients and 121 controls (38 healthy controls, 43 patients with other inflammatory rheumatic diseases, 20 osteoarthritis patients and 20 subjects with mechanical joint complaints). Fourteen novel autoantibodies were identified that showed a 54% sensitivity and 90% specificity for RA. For 11 of these autoantibodies, an exclusive presence was demonstrated in RA patients (100% specificity, 37% sensitivity) as compared to controls. All early RA patients were positive for at least one of the identified autoantibodies and antibody-positivity was associated with a shorter disease duration (P = 0.0087). 52% of RA patients who initially tested negative for RF and ACCP, tested positive for at least one of the 14 novel autoantibodies, resulting in a 19% increase in sensitivity compared to current serological testing. Moreover, 5 identified autoantibodies were detected more frequently in seronegative RA patients, indicating that these autoantibodies constitute novel candidate markers for this RA subtype. We demonstrated that the targets of 3 of these 5 autoantibodies had an increased expression in RA synovial tissue compared to control synovial tissue, pointing towards a biological rationale for these auto antibody targets in RA.In conclusion, we identified novel candidate autoantibody markers for RA that can be detected in early and seronegative RA patients indicating the potential added value for RA diagnostics. 相似文献
69.
Meyer-Schwesinger C Meyer TN Sievert H Hoxha E Sachs M Klupp EM Münster S Balabanov S Carrier L Helmchen U Thaiss F Stahl RA 《The American journal of pathology》2011,178(5):2044-2057
Ubiquitin C-terminal hydrolase L1 (UCH-L1), a key protease of the ubiquitin-proteasome system (UPS), is associated with neurodegenerative diseases and cancer. Recently, de novo expression of UCH-L1 was described in podocytes in patients with membranous nephropathy (MN), in which UCH-L1 expression correlated with increased ubiquitin content. The objective of the present study was to investigate the role of UCH-L1 in ubiquitin homeostasis and proteasomal degradation in a rat model of MN. After disease induction, UCH-L1 expression increased in podocytes and coincided with decreased glomerular monoubiquitin content. After an initial increase in proteasomal activity, the UPS was impaired. In addition to an increase of ubiquitin in podocytes, aggregates were observed 1 year after disease induction, as in MN in human beings. Inhibition of UCH-L1 hydrolase function in MN reduced UPS impairment and ameliorated proteinuria. In contrast, inhibition of proteasomal activity enhanced UPS impairment, resulting in increased proteinuria. Stable UCH-L1 overexpression in cultured podocytes resulted in accumulation of monoubiquitin and polyubiquitin proteins. In contrast, stable knock-down of UCH-L1 reduced monoubiquitin and polyubiquitin proteins and significantly increased proteasomal activity, indicating that the observed effects in rat MN also occurred in cultured podocytes. These data demonstrate that UCH-L1 activity results in polyubiquitin accumulation, proteasome inhibition, and disease aggravation in experimental models of MN. 相似文献
70.
Korevaar MA Goorden MC Heemskerk JW Beekman FJ 《Physics in medicine and biology》2011,56(15):4785-4801
Gamma cameras based on charge-coupled devices (CCDs) coupled to continuous scintillation crystals can combine a good detection efficiency with high spatial resolutions with the aid of advanced scintillation detection algorithms. A previously developed analytical multi-scale algorithm (MSA) models the depth-dependent light distribution but does not take statistics into account. Here we present and validate a novel statistical maximum-likelihood algorithm (MLA) that combines a realistic light distribution model with an experimentally validated statistical model. The MLA was tested for an electron multiplying CCD optically coupled to CsI(Tl) scintillators of different thicknesses. For (99m)Tc imaging, the spatial resolution (for perpendicular and oblique incidence), energy resolution and signal-to-background counts ratio (SBR) obtained with the MLA were compared with those of the MSA. Compared to the MSA, the MLA improves the energy resolution by more than a factor of 1.6 and the SBR is enhanced by more than a factor of 1.3. For oblique incidence (approximately 45°), the depth-of-interaction corrected spatial resolution is improved by a factor of at least 1.1, while for perpendicular incidence the MLA resolution does not consistently differ significantly from the MSA result for all tested scintillator thicknesses. For the thickest scintillator (3 mm, interaction probability 66% at 141 keV) a spatial resolution (perpendicular incidence) of 147 μm full width at half maximum (FWHM) was obtained with an energy resolution of 35.2% FWHM. These results of the MLA were achieved without prior calibration of scintillations as is needed for many statistical scintillation detection algorithms. We conclude that the MLA significantly improves the gamma camera performance compared to the MSA. 相似文献