Blutungen am VAD-System

The effects of ventricular assist devices (VADs) on the coagulation system are not yet fully understood. The high molecular weight (HMW) von Willebrand factor (vWF) decrease observed after continuous flow left VAD (CF-LVAD) implantation has been well documented by several studies. However, not all CF-LVAD recipients suffer from bleeding complications so that additional risk factors need to be identified by further studies. If predictors of bleeding complications were known in more detail this would facilitate the development of individualized strategies for anticoagulation and antiplatelet therapy in VAD recipients. In the face of the significant mortality associated with bleeding this complication remains a major obstacle in improving patient outcome which should be overcome.     

Periprosthetic bone mineral density after total hip arthroplasty with an AMIStem or Quadra femoral component performed by a minimally invasive anterior approach (AMIS): a prospective randomized clinical dual-energy X-ray absorptiometry study

Introduction

This prospective 12 months of dual-energy X-ray absorptiometry (DEXA) study evaluated differences in periprosthetic bone mineral density in 40 patients undergoing cementless total hip arthroplasty (THA) by a minimally invasive anterior approach (AMIS), using Medacta AMIStem or Quadra stems. Both stems are straight rectangular. AMIStem shows reduced lateral flare and length in comparison to Quadra.

Objectives

The main goal of the study is to verify if bone mineral density is equivalent following THA with the AMIStem and Quadra femoral components.

Methods

Forty patients were randomly allocated to the Quadra and AMIStem groups. Three patients were lost to follow-up because they moved to another town, and revision surgery was performed on one patient due to periprosthetic fracture after a car accident. Patients were examined clinically and underwent DEXA preoperatively and at 1 week, 6 weeks, 6 months, and 1 year after THA. Patients enrolled had no preexisting lower limb arthroplasty and no osteoporosis.

Results

Harris hip score increased significantly for Quadra stem 5.3?±?14.1 and AMIStem 41.0?±?13.4. The high-activity hip score increased significantly for Quadra stem 3.8 ±2.2 and AMIStem 4.1?±?2.4. Considering 0.15 mg/cm² as an acceptable difference, bone mineral density for AMIStem and Quadra groups was statistically equivalent. A limited remodeling process with slight bone loss in the proximal calcar region R7, as expected after implantation of uncemented components, was observed for both stems.

Conclusions

The study demonstrates that the two stems are statistically equivalent in all zones at all time points investigated.     

Reassessing the Impact of Donor HLA-C Genotype on Long-Term Liver Transplant Survival

HLA-C is the major inhibitory ligand for killer immunoglobulin-like receptors (KIRs) that are expressed on natural killer (NK) cells. Based on their KIR specificity, HLA-C alleles can be divided into two groups, termed HLA-C1 and HLA-C2. Donor HLA-C group has recently been identified by Hanvesakul et al. (Am J Transplant 2008) as a critical determinant of clinical outcome following liver transplantation: Possession of at least one HLA-C group 2 allele by the donor was associated with significantly improved long-term graft and patient survival, presumably due to an inhibition of host NK cell function. To verify this study, we performed genotyping of 913 deceased liver donors for the relevant KIR epitopes of HLA-C and correlated the presence or absence of donor HLA-C2 genotype with graft and patient survival. In our study, donor HLA-C2 genotype had no impact on 10-year graft or patient survival. We cannot confirm a major role of donor HLA-C2 genotype on long-term allograft survival after liver transplantation.     

The NeuroDevNet Autism Spectrum Disorders Demonstration Project

The NeuroDevNet Autism Spectrum Disorder Demonstration Project interfaces at many levels with the network's research themes and priorities. Our interdisciplinary team aims to improve understanding of genetic factors underlying vulnerability to autism spectrum disorders (ASDs) to develop better diagnostic strategies and, ultimately, to pinpoint molecular pathways relevant to developing biologically based treatments. Linking our existing longitudinal ASD cohorts with both genetics and neuroimaging studies will provide, for the first time, integrated data on how the genetic variation influences brain and behavioral development in ASD. Importantly, as our science progresses and we translate this information to the health care system, we will also educate policy makers, media, and business, so an informed society is prepared to capitalize on new genomic advances and effectively integrate these into health services for the broader community. We believe that this research has the potential to transform assessment and care for individuals with ASD.     

Kv7.2 regulates the function of peripheral sensory neurons

The Kv7 (KCNQ) family of voltage‐gated K⁺ channels regulates cellular excitability. The functional role of Kv7.2 has been hampered by the lack of a viable Kcnq2‐null animal model. In this study, we generated homozygous Kcnq2‐null sensory neurons using the Cre‐Lox system; in these mice, Kv7.2 expression is absent in the peripheral sensory neurons, whereas the expression of other molecular components of nodes (including Kv7.3), paranodes, and juxtaparanodes is not altered. The conditional Kcnq2‐null animals exhibit normal motor performance but have increased thermal hyperalgesia and mechanical allodynia. Whole‐cell patch recording technique demonstrates that Kcnq2‐null sensory neurons have increased excitability and reduced spike frequency adaptation. Taken together, our results suggest that the loss of Kv7.2 activity increases the excitability of primary sensory neurons. J. Comp. Neurol. 522:3262–3280, 2014. © 2014 Wiley Periodicals, Inc.     

A new mutation in GJC2 associated with subclinical leukodystrophy

Recessive mutations in GJC2, the gene-encoding connexin 47 (Cx47), cause Pelizaeus–Merzbacher-like disease type 1, a severe dysmyelinating disorder. One recessive mutation (p.Ile33Met) has been associated with a much milder phenotype––hereditary spastic paraplegia type 44. Here, we present evidence that a novel Arg98Leu mutation causes an even milder phenotype––a subclinical leukodystrophy. The Arg98Leu mutant forms gap junction plaques in HeLa cells comparable to wild-type Cx47, but electrical coupling was 20-fold lower in cell pairs expressing Arg98Leu than for cell pairs expressing wild-type Cx47. On the other hand, coupling between Cx47Arg98Leu and Cx43WT expressing cells did not show such reductions. Single channel conductance and normalized steady-state junctional conductance–junctional voltage (G _j–V _j) relations differed only slightly from those for wild-type Cx47. Our data suggest that the minimal phenotype in this patient results from a reduced efficiency of opening of Cx47 channels between oligodendrocyte and oligodendrocyte with preserved coupling between oligodendrocyte and astrocyte, and support a partial loss of function model for the mild Cx47 associated disease phenotypes.     

Hemodynamic and respiratory changes in operations of the esophagus by unilateral ventilation

One-lung ventilation offers optimal operating conditions during intrathoracic surgery. Hemodynamic and respiratory changes were measured in 9 patients. Cardiac output was unchanged, arterial pO2 decreased and venous admixture increased markedly. The increase in mean pulmonary artery pressure and pulmonary vascular resistance are signs for hypoxic pulmonary vasoconstriction in the unventilated lung. In spite of an inspiratory oxygen concentration of 66% oxygen availability was decreased by about 20%. Anaesthesia and related procedures should not interfere with pulmonary autoregulation. Complete monitoring is necessary to safely assess oxygenation of the patient.     

Procedural learning in schizophrenia can reflect the pharmacologic properties of the antipsychotic treatments.

BACKGROUND: Conventional and atypical antipsychotics have different affinities for D2 receptors, and these receptors are principally located in the striatum. Given that this cerebral structure was previously found to play a major role in procedural learning, the antipsychotic treatment in schizophrenia may be determinant for the procedural learning profile of these patients. OBJECTIVE: The current study was aimed at verifying whether procedural learning differs in patients with schizophrenia treated with conventional antipsychotics and patients treated with atypical antipsychotics. METHOD: Forty-five patients with schizophrenia were divided into 3 different groups according to their pharmacologic treatment: (1) haloperidol, a classical neuroleptic with high D2 receptor affinity; (2) clozapine, an atypical neuroleptic with practically no D2 receptor affinity; and (3) risperidone, an atypical neuroleptic that nevertheless shows high D2 receptor affinity. Patients were compared to 35 control subjects on a visuomotor procedural learning task (mirror drawing). RESULTS: All patients were able to learn the task. However, those treated with haloperidol showed some degree of learning impairment, while those treated with clozapine or risperidone did not show this impairment. In addition, performance per se, regardless of the learning, was found to be affected in the haloperidol and risperidone, but not in the clozapine groups. CONCLUSION: Procedural learning in schizophrenia may be differentially affected, depending on the pharmacologic profiles of the antipsychotics used for the treatment of this illness.     

Multidetektor-Computertomographie (MDCT) bei Nieren- und Hochdruckkrankheiten

Imaging of renal and hypertonic diseases has also profited from multidetector computed tomography which is now widely available. MDCT is increasingly being used when there are indications for conventional (invasive) angiography and has completely supplanted i.v. urography. In order to minimize the total radiation dose a tailor-made investigation protocol must be applied in every situation. As far as this makes sense low-dose protocols (e.g. for the diagnosis of urolithiasis) should be applied. Improvement of the longitudinal resolution (z-axis) and the resulting isotropic voxels means that many options for image reconstruction are now available. The production of multiplanar reconstructions, thinner slice or 3-D reconstruction can greatly assist the diagnosis in many cases. The fundament of a conclusive examination is also a good communication between clinical physicians and radiologists.