A multicenter randomized controlled trial indicates that paclitaxel-coated balloons provide no benefit for arteriovenous fistulas.

The role of paclitaxel-coated balloons has been established in the coronary and peripheral arterial circulations with recent interest in the use of paclitaxel-coated balloons to improve patency rates following angioplasty of arteriovenous fistulas. To assess the efficacy of paclitaxel-coated angioplasty balloons to prolong the survival time of target lesion primary patency in arteriovenous fistulas, we designed an investigator-led multi-center randomized controlled trial with follow up time variable for a minimum of one year. Patients with an arteriovenous fistula who were undergoing an angioplasty for a clinical indication were included but patients with one or more lesions outside the treatment segment were excluded. Following successful treatment with a high-pressure balloon, 212 patients were randomized. In the intervention arm, the second component was insertion of a paclitaxel-coated balloon. In the control arm, an identical procedure was followed, but using a standard balloon. The primary endpoint was time to loss of clinically driven target lesion primary patency. Primary analysis showed no significant evidence for a difference in time to end of target lesion primary patency between groups: hazard ratio 1.18 with a 95% confidence interval of 0.78 to 1.79. There were no significant differences for any secondary outcomes, including patency outcomes and adverse events. Thus, our study demonstrated no evidence that paclitaxel-coated balloons provide benefit, following standard care high-pressure balloon angioplasty, in the treatment of arteriovenous fistulas. Hence, in view of the benefit suggested by other trials, the role of paclitaxel-coated angioplasty balloons remains uncertain.

Paclitaxel-coated balloon fistuloplasty versus plain balloon fistuloplasty only to preserve the patency of arteriovenous fistulae used for haemodialysis (PAVE): study protocol for a randomised controlled trial.

BACKGROUND: The initial therapy for a stenosis in an arteriovenous fistula used for haemodialysis is radiological balloon dilatation or angioplasty. The benefit of angioplasty is often short-lived, intervention-free survival is reported to be 40-50 % at 1 year. Previous small studies and observational data suggest that paclitaxel-coated balloons may be of benefit in improving outcomes after fistuloplasty of stenotic arteriovenous fistulae. METHODS/DESIGN: We have designed a multicentre, double-blind randomised controlled trial to test the superiority of paclitaxel-coated balloons for preventing restenosis after fistuloplasty in patients with a native arteriovenous fistula. Two hundred and eleven patients will be followed up for a minimum of 1 year. Inclusion criteria include a clinical indication for a fistuloplasty, an access circuit that is free of synthetic graft material or stents, and a residual stenosis of 30 % or less after plain balloon fistuloplasty. Exclusion criteria include a synchronous venous lesion in the same access circuit, location of the stenosis central to the thoracic inlet or a thrombosed access circuit at the time of treatment. The primary endpoint is time to end of target lesion primary patency. This is defined as a clinically-driven radiological or surgical re-intervention at the treatment segment, thrombosis that includes the treatment segment, or abandonment of the access circuit due to an inability to re-treat the treatment segment. Secondary endpoints include angiographic late lumen loss, time to end of access circuit cumulative patency, the total number of interventions, and quality of life. The trial is funded by the National Institute for Health Research. DISCUSSION: We anticipate that this trial will provide rigorous data that will determine the efficacy of additional paclitaxel-coated balloon fistuloplasty versus plain balloon fistuloplasty only to preserve the patency of arteriovenous fistulae used for haemodialysis. TRIAL REGISTRATION: ISRCTN14284759 . Registered on 28 October 2015.

Systematic assessment of the influence of complement gene polymorphisms on kidney transplant outcome.

The importance of the innate immune system, including complement, in causing transplant injury and augmenting adaptive immune responses is increasingly recognized. Therefore variability in graft outcome may in part be due to genetic polymorphism in genes encoding proteins of the immune system. This study assessed the relationship between single nucleotide polymorphisms (SNPs) in complement genes and outcome after transplantation. Analysis was performed on two patient cohorts of 650 and 520 transplant recipients. 505 tagged SNPs in 47 genes were typed in both donor and recipient. The relationships between SNPs and graft survival, serum creatinine, delayed graft function and acute rejection were analyzed. One recipient SNP in the gene encoding mannose binding lectin was associated with graft outcome after correction for analysis of multiple SNPs (p=6.41 × 10(-5)). When further correction was applied to account for analysis of the effect of SNPs in both donor and recipient this lost significance. Despite association p values of <0.001 no SNP was significantly associated with clinical phenotypes after Bonferroni correction. In conclusion, the variability seen in transplant outcome in this patient cohort cannot be explained by variation in complement genes. If causal genetic effects exist in these genes, they are too small to be detected by this study.

Immune and viral profile from tolerance to hepatitis B surface antigen clearance: a longitudinal study of vertically hepatitis B virus-infected children on combined therapy.

The aim of the study was to investigate longitudinally hepatitis B virus (HBV)-specific T-cell reactivity and viral behavior versus treatment response in tolerant children during combined antiviral therapy. Twenty-three children with infancy-acquired hepatitis B (HBeAg(+)) belonging to a published pilot study of 1-year treatment with lamivudine/alpha interferon (IFN-α) were investigated. Five seroconverted to anti-HBs (responders). Nine were HLA-A2(+) (4 responders and 5 nonresponders). Mutations within the HBV core gene were determined at baseline in liver and in serial serum samples by direct sequencing at baseline; during treatment week 2 (TW2), TW9, TW28, and TW52; and after follow-up week 24 (FUW24) and FUW52. HBV-specific reactivity was evaluated by T-cell proliferation with 16 HBV core 20-mer overlapping peptides and by HLA-A2-restricted core(18-27) pentamer staining and CD8(+) IFN-γ enzyme-linked immunospot (ELISPOT) assay. HBV core-specific T-cell proliferative and CD8 responses were more vigorous and broader among responders than among nonresponders at TW28 and TW52, while the number of mutations within HBV core gene immunodominant epitopes was lower at TW28 and was negatively associated with HBV-specific T-cell proliferative responses at both time points. The HBV DNA viral load was negatively associated with HBV-specific T-cell proliferative and CD8 responses during treatment, especially at TW28. Treatment-induced transition from immunotolerance to HBV immune control is characterized by the emergence of efficient virus-specific immune responses capable of restraining mutations and preventing viral evasion.

Impaired intellect and memory: a missing link between genetic risk and schizophrenia?

CONTENT: The DSM-IV concept of schizophrenia offers diagnostic reliability but etiologic and pathologic heterogeneity, which probably contributes to the inconsistencies in genetic studies. One solution is to identify intermediate phenotypes, "narrower" constructs of liability, that hypothetically share genetic risk with the disorder. Although a variety of candidate intermediate phenotypes have emerged, few have explicitly quantified the extent of their genetic overlap with schizophrenia. OBJECTIVE: To quantify the net-shared genetic effects between schizophrenia and specific cognitive candidate intermediate phenotypes. DESIGN: Twin and family design. SETTING: Adult psychiatric research centers in the United States and the United Kingdom. PARTICIPANTS: A total of 2056 participants: 657 patients with schizophrenia, 674 first-degree relatives (including co-twins), and 725 controls. MAIN OUTCOME MEASURES: (1) Latent factors capturing the common variance between cognitive tasks, (2) separation of the latent factors into their genetic and environmental components, and (3) estimation of the net-shared genetic variance between the latent cognitive factors or intelligence and schizophrenia. RESULTS: Genetic factors contributed substantially to the total variance in cognition (immediate recall latent factor: 0.66; 95% confidence interval [CI], 0.62 to 0.85; delayed recall latent factor: 0.48; 0.42 to 0.55; and intelligence: 0.66; 0.62 to 0.71). The latent common factors for modality-specific immediate and delayed recall and intelligence showed similar levels of phenotypic covariance with schizophrenia (immediate recall: -0.35; delayed recall: -0.37; and intelligence: -0.38), with 72%, 86%, and 89%, respectively, due to shared genetic effects with schizophrenia. Environmental effects accounted for little phenotypic correlation between cognition and schizophrenia. CONCLUSIONS: Using the largest international familial schizophrenia cohort to date, we showed that a substantial portion of the phenotypic correlation between schizophrenia and cognition is caused by shared genetic effects. However, because the phenotypic and genetic correlations are far from unity, the genetics of schizophrenia are clearly not merely the genetics of cognition.