Atherosclerotic renal artery stenosis (ARAS) is one of the most relevant long-term complications of atherosclerotic disease. It is associated both with hypertension and increased renal and ...cardiovascular risk and overall mortality. Diagnostic modalities include non-invasive duplex ultrasound, dynamic magnetic resonance angiography (MRA) and computer tomography angiography (CTA) and are confirmed by using invasive renal angiography. Percutaneous revascularization of renal artery stenosis has been studied in various clinical trials. With regard to hypertension, several case series could show a clinical response to revascularization. However, the majority of randomized clinical trials could not confirm the correlation between intervention and the improvement of hypertension, kidney function, cardiovascular events, and mortality. Based on this predication the crucial tool in the treatment of ARAS is an optimal medical therapy, including statins, antihypertensive agents and platelet inhibition. Today the core point is to select subgroups and appropriate indications for better outcomes and avoiding unnecessary procedures very carefully. Therefore in patients with typical manifestations of ARAS including resistant or malignant hypertension, progressive decline of renal function, flash pulmonary edema or angina, renal artery intervention remains a sensible therapeutic option - after hemodynamic testing prior to revascularization. In the future further trials targeting patients who fulfill rational selection criteria need to be undertaken to confirm the efficacy of revascularization.
We have carried out an (e,e'p) experiment at high momentum transfer and in parallel kinematics to measure the strength of the nuclear spectral function S(k,E) at high nucleon momenta k and large ...removal energies E. This strength is related to the presence of short-range and tensor correlations, and was known hitherto only indirectly and with considerable uncertainty from the lack of strength in the independent-particle region. This experiment locates by direct measurement the correlated strength predicted by theory.
Abstract Purpose To evaluate the effect of cold ischemia time (CIT) of renal allografts on diffusion and perfusion using intravoxel incoherent motion (IVIM) derived parameters. Material and methods A ...total of 37 patients with renal allografts (CIT: 27 <15 h, 10 ≥15 h) and 30 individuals with healthy kidneys were examined at 1.5 T using a single-shot echo-planar diffusion-weighted pulse sequence with nine b -values ranging from 0 to 800 s/mm2 . ADC, perfusion fraction f , and the diffusion coefficient D were calculated using the IVIM model. Parameters of allografts stratified by CIT were compared with healthy kidney groups using the Mann–Whitney U test for unpaired data. We computed the Spearman correlation coefficient for correlation with creatinine values. Results ADC, D , and f of transplanted kidneys were significantly lower than in the healthy controls. The long-CIT group showed significantly lower diffusion parameters compared with the short-CIT group mean ± SD: ADC: 1.63 ± 0.14 μm2 /ms, f : 11.90 ± 5.22%, D : 1.55 ± 0.25 μm2 /ms versus ADC: 1.79 ± 0.13 μm2 /ms, f : 16.12 ± 3.43%, D : 1.73 ± 0.14 μm2 /ms, PADC , f , D < 0.05. Conclusion Our results suggest that diffusion parameters, especially the ADC, depend on the CIT of the kidney allograft. Potentially, this stands for functional changes in renal allografts. Diffusion-weighted imaging could be used for follow-up examinations. Thus, diffusion parameters may help guide therapy in patients with delayed graft function.
Abstract Introduction Real-time contrast-enhanced sonography (CES) can assess microvascular tissue perfusion using gas-filled microbubbles. The purpose of the study was to evaluate the feasibility of ...early CES in predicting long-term kidney allograft function in comparison to color Doppler ultrasonography (CDUS). Methods We prospectively studied 68 consecutive kidney transplant recipients using CES and conventional CDUS investigation 1 week after transplantation. Transplant tissue perfusion imaging was performed by low-power imaging during intravenous administration of the sonocontrast SonoVue. Renal tissue perfusion was assessed quantitatively using flash replenishment kinetics of microbubbles to estimate renal blood flow (RBF). The obtained sonography values were correlated with clinical data 1 week up to 1 year after transplantation. Results In contrast with conventional CDUS resistive indices, RBF estimated by CES 1 week posttransplantation significantly correlated with kidney function after 1 year ( r = 0.67; P < .001). Determination of RBF by CES revealed a significant correlation with donor age but not recipient age, whereas conventional CDUS resistive index was significantly correlated to recipient age ( r = 0.54; P < .001) but not donor age. Furthermore RBF was associated with vascular fibrosis and intimal thickening of the engraftment biopsies. Conclusion This is the first prospective study demonstrating the prognostic value of CES early after kidney transplantation. In contrast with CDUS, CES reveals information about kidney allograft perfusion independent of recipient vascular compliance.
Presensitized kidney transplant recipients are at high‐risk for early antibody‐mediated rejection. We studied the impact of pre‐ and post‐transplant donor‐specific human leukocyte antigen (HLA) ...antibodies (DSA) and T‐cell‐activation on the occurrence of antibody‐mediated rejection episodes (AMR) and graft loss (AMR‐GL) in a unique cohort of 80 desensitized high‐risk kidney transplant recipients. Patients with pre‐transplant DSA demonstrated more AMR episodes than patients without DSA, but did not show a significantly increased rate of AMR‐GL. The rates of AMR and AMR‐GL were not significantly increased in patients with complement split product (C1q)‐binding pre‐transplant DSA. Pre‐transplant C1q‐DSA became undetectable post‐transplant in 11 of 13 (85%) patients; 2 (18%) of these 11 patients showed AMR but no AMR‐GL. In contrast, the post‐transplant presence of C1q‐DSA was associated with significantly higher rates of AMR (86 vs 33 vs 0%; P < 0.001) and AMR‐GL (86 vs 0 vs 0%; log‐rank P < 0.001) compared with post‐transplant DSA without C1q‐binding or the absence of DSA. Patients with both pre‐transplant DSA and evidence of pre‐transplant T‐cell‐activation as indicated by soluble CD30‐positivity showed a significantly increased risk for AMR‐GL HR = 11.1, 95% confidence interval (CI) = 1.68–73.4; log‐rank P = 0.013. In these high‐risk patients, AMR‐GL was associated with total DSA in combination with T‐cell‐activation pre‐transplant, and de novo or persistent C1q‐binding DSA post‐transplant.
A resistance index (RI) of 0.8 or higher was shown to be a strong predictor of kidney allograft and patient survival. Uncertainties persist since the intrarenal RI is closely associated with the ...vascular stiffness of the allograft recipient. To clarify the diagnostic value of RI further, we analyzed parameters of vascular stiffness of the recipient and intrarenal RI of the renal allograft. In a prospective study laboratory and clinical parameters, pulse wave velocity (PWV), intima media thickness (IMT) and RI were obtained in 76 kidney allograft patients. We found that the RI values significantly correlated with the PWV (p < 0.05) and the recipients age (p < 0.01) but not with the donor age and renal function. Using multiple regression analysis recipient age, PWV, pulse pressure (PP) and IMT were identified as independent factors influencing RI values. For a more correct interpretation of the RI values in renal allografts parameters of vascular stiffness such as IMT, PP or PWV should be included.
Resistive index values in renal allografts can be interpreted more accurately if parameters of vascular stiffness are also considered.
Metrology dedicated to electricity and magnetism has changed considerably in recent years. It encompasses almost all modern scientific, industrial, and societal challenges, e.g. the revision of the ...International System of Units, the profound transformation of industry, changes in energy use and generation, health, and environment, as well as nanotechnologies (including graphene and 2D materials) and quantum engineering. Over the same period, driven by the globalization of worldwide trade, the Mutual Recognition Arrangement (referred to as the CIPM MRA) was set up. As a result, the regional metrology organizations (RMOs) of national metrology institutes have grown in significance. EURAMET is the European RMO and has been very prominent in developing a strategic research agenda (SRA) and has established a comprehensive research programme. This paper reviews the highlights of EURAMET in electrical metrology within the European Metrology Research Programme and its main contributions to the CIPM MRA. In 2012 EURAMET undertook an extensive roadmapping exercise for proposed activities for the next decade which will also be discussed in this paper. This work has resulted in a new SRA of the second largest European funding programme: European Metrology Programme for Innovation and Research.
Patients with multiple myeloma and dialysis-dependent renal failure have dismal outcomes. In this retrospective analysis of a case series, we evaluated 27 consecutive patients, all of whom required ...haemodialysis at the time of first-line induction therapy with either bortezomib or a standard regimen followed by high-dose chemotherapy and auto-SCT. The overall response rate was significantly better after bortezomib-based induction before auto-SCT (83% vs 36%, P=0.02) and at day +100 post auto-SCT (100% vs 58%, P=0.01). Bortezomib also prolonged EFS and furthermore, a trend towards a shorter time on haemodialysis was observed in the bortezomib group at a median of 6.1 months (0.2-68.2 months) vs 17.1 months (0.7-94.3 months, P=0.38) in patients who had received vincristine, adriamycin, dexamethasone or vincristine, adriamycin, dexamethasone-like induction regimens. These data demonstrate the superior efficacy of bortezomib-based induction therapy in transplant-eligible patients with end-stage renal failure.
Cytomegalovirus (CMV) can cause severe infections with serious consequences in renal transplant recipients. Disseminated CMV infections can affect almost every organ, but obstructive cholestasis and ...cholangitis, as a consequence of a CMV‐induced papillitis, is extremely rare. We are reporting a rare case of obstructive cholestasis and cholecystitis due to CMV‐related inflammation of the major duodenal papilla in a 60‐year‐old woman 3 months after renal transplantation. In addition, the patient suffered from a disseminated CMV infection with ulcerative esophagitis and gastritis. Because of the severe CMV infection, failure of the renal graft occurred. Obstructive cholestasis was resolved through internal stenting, and the progressive cholecystitis necessitated an emergency cholecystectomy. Following antiviral therapy with ganciclovir, the gastrointestinal ulcerations regressed and renal function was restored. Diagnosis of the CMV‐related disease was established only in tissue samples, whereas standard serologic tests had failed.
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