Hemodynamic stress during hemodialysis (HD) results in recurrent segmental ischemic injury (myocardial stunning) that drives cumulative cardiac damage. We performed a fully comprehensive study of the cardiovascular effect of dialysis sessions using intradialytic cardiac magnetic resonance imaging (MRI) to examine the comparative acute effects of standard HD versus hemodiafiltration (HDF) in stable patients. We randomly allocated 12 patients on HD (ages 32–72 years old) to either HD or HDF. Patients were stabilized on a modality for 2 weeks before undergoing serial cardiac MRI assessment during dialysis. Patients then crossed over to the other modality and were rescanned after 2 weeks. Cardiac MRI measurements included cardiac index, stroke volume index, global and regional contractile function (myocardial strain), coronary artery flow, and myocardial perfusion. Patients had mean±SEM ultrafiltration rates of 3.8±2.9 ml/kg per hour during HD and 4.4±2.5 ml/kg per hour during HDF (P=0.29), and both modalities provided a similar degree of cooling. All measures of systolic contractile function fell during HD and HDF, with partial recovery after dialysis. All patients experienced some degree of segmental left ventricular dysfunction, with severity proportional to ultrafiltration rate and BP reduction. Myocardial perfusion decreased significantly during HD and HDF. Treatment modality did not influence any of the cardiovascular responses to dialysis. In conclusion, in this randomized, crossover study, there was no significant difference in the cardiovascular response to HDF or HD with cooled dialysate as assessed with intradialytic MRI.

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Two synthetic routes to compounds [(η 5 -C 5 H 4 SiMe 3 ) 2

The patient's organic dysfunction primarily determines illness-specific complaints but has little relevance for the psychological and social aspects of the HRQL. These aspects are predominantly determined by the patient's depressive disposition and by the experienced social support. A successful therapy should therefore take biological as well as psycho-social determinants of the quality of life into account.

The synthesis and characterization, including crystallographic analysis, of the bifunctional boranes RCHdC[B(C 6 F 5 ) 2 ] 2 (R ) t-C 4 H 9 , 1a; C 6 H 5 , 1b; C 6 F 5 , 1c) by regioselective hydroboration of the corresponding 1-boraalkynes using HB(C 6 F 5 ) 2 are reported herein. Compounds 1a and 1b have been screened as cocatalysts for ethylene polymerization in the presence of Cp 2 ZrMe 2 (3) under a variety of conditions. NMR spectroscopic studies indicate that Cp 2 -Zr[η 2 -Bu t CtCB(C 6 F 5 ) 2 ] (4a), Cp 2 ZrMe(C 6 F 5 ), the organoborane Me 2 BC 6 F 5 , and methane gas are the final products formed from reaction of 1a with 3 in toluene solution at room temperature. The stoichiometric mechanism for this transformation has been elucidated through variable-temperature NMR studies. Complex 4a and MeB(C 6 F 5 ) 2 (7) were prepared independently and screened as ethylene polymerization catalysts and cocatalysts, respectively. Compound 4a is inactive for ethylene polymerization, either alone or in the presence of additional 1a. However, the combination of Cp 2 ZrMe 2 and 7 gives rise to the species [Cp 2 ZrMe] + [Me 2 B(C 6 F 5 ) 2 ] -(8), which although unstable at room temperature in solution (decomposing over a period of 60 min to give Cp 2 ZrMe(C 6 F 5 ) and the organoborane Me 2 -BC 6 F 5 ), is active for ethylene polymerization. From a comparison of activity and MW data, it is concluded that the putative ion pairs formed from 1a (or 1b) and 3 lack sufficient thermal stability at conventional polymerization temperatures and that the polymerization activity observed can be interpreted as arising from species 8.

Microcirculatory disturbances are an initial causative determinant in hepatic ischemia/reperfusion injury. The aim of this study was to assess sinusoidal perfusion during human liver transplantation using orthogonal polarization spectral imaging and to evaluate the significance of intraoperative microcirculation for early postoperative graft function. Hepatic microcirculation was measured in 27 recipients undergoing full-size liver transplantation and compared to a group of 32 healthy living-related liver donors. The microvascular parameters were correlated with postoperative aspartate aminotransferase and bilirubin levels. Hepatic perfusion following liver transplantation was found to be significantly decreased when compared with the control group.

Online haemodiafiltration (HDF) represents today the most advanced and innovative form of renal replacement therapy (RRT). Recent controlled trials tend to prove its superiority over conventional haemodialysis on hard clinical end points provided that the right convective dose was delivered. In this article we report on present prevalent use and epidemiologic trends of HDF worldwide as well as on practice patterns in HDF prescription. In addition we analyze factors that may affect HDF clinical acceptance and more widely its implementation. National and international renal registries provide valuable demographic and epidemiologic information on end stage kidney disease patients on RRT. However, the updating and maintenance of such information system is particularly challenging at a country level and even more so on an international basis. Lag time, incompleteness and/or imprecision of data collection may further hamper precision and validity of data reporting. Fresenius Medical Care (FMC), as a large dialysis care provider operating worldwide, maintains an annually updated database addressing international end stage kidney disease data. Over the last decade, FMC has produced series of precise and reliable reports analyzing RRT trends and practices worldwide. The present overview and analysis is based on our consolidated data from market survey as well as national database registries and databases of recent studies. Online HDF acceptance is growing fast in the two leading regions having approved the method, i.e. Europe and Asia Pacific, with a patient average growth rate of 12 to 24%, being far above the total patient HD growth rate of 6.6%. Today online HDF represents a new paradigm shift in RRT with promising clinical results. Further initiatives (e.g., Kidney Health Initiative, NICE) might provide further push for promoting HDF as a new standard of care in end stage kidney disease patients on a global scale.

Silver(I) and rhodium(I) complexes bearing the bisallyl-substituted N-heterocyclic carbene ligand (4R,5S)-4,5-diallyl-1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene (allyl 2 SIMes) have been prepared in a straightforward synthesis. The reaction of (4R,5S)-4,5-diallyl-1,3bis(2,4,6-trimethylphenyl)-4,5-dihydro-3H-imidazol-1-ium tetrafluoroborate (1a) with Ag 2 O affords the ionic biscarbene complex [(allyl 2 SIMes) 2 Ag] + BF 4 -(2), while the reaction of (4R,5S)-4,5-diallyl-1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydro-3H-imidazol-1-ium chloride (1b) with Ag 2 O leads to the monocarbene complex (allyl 2 SIMes)AgCl (3). Sequential treatment of 1a with KOtBu and dimeric [RhCl(cod)] 2 (cod ) cyclooctadiene) yields the rhodium carbene complex (allyl 2 SIMes)RhCl(cod) (4). However, the reaction of 1a with the first-generation Grubbs catalyst (PCy 3 ) 2 Cl 2 RudC(H)Ph (Cy ) cyclohexyl) leads to ring-closing metathesis of the two allylic groups, yielding 1,3-bis(2,4,6-trimethylphenyl)-3a,4,7,7a-tetrahydro-3Hbenzimidazol-1-ium tetrafluoroborate (5). Subsequent reaction of this new imidazolium salt with KOtBu and 1 equiv of (PCy 3 )Cl 2 RudC(H)(C 6 H 4 OiPr-2) forms [1,3-bis(2,4,6-trimethylphenyl)-3a,4,7,7a-tetrahydro-3H-benzimidazolin-2-ylidene]dichloro(2-isopropanolatobenzylidene)ruthenium(II) (8). All new complexes have been thoroughly characterized, including X-ray crystallographic analyses of 2, 3, and 8. The most intriguing feature of 8 is the presence of an innocent CdC bond that is part of a highly active olefin metathesis catalyst, which offers many options for further functionalization of the ligand backbone. The catalytic activity of complex 8 has been evaluated for the ring-closing metathesis of N,N-diallyl-4-toluenesulfonamide.