34 research outputs found
Sofosbuvir and Ribavirin Prevent Recurrence of HCV Infection After Liver Transplantation: An Open-Label Study
Background & AimsPatients with detectable hepatitis C virus (HCV) RNA at the time of liver transplantation universally experience recurrent HCV infection. Antiviral treatment before transplantation can prevent HCV recurrence, but existing interferon-based regimens are poorly tolerated and are either ineffective or contraindicated in most patients. We performed a trial to determine whether sofosbuvir and ribavirin treatment before liver transplantation could prevent HCV recurrence afterward.MethodsIn a phase 2, open-label study, 61 patients with HCV of any genotype and cirrhosis (ChildâTurcotteâPugh score, â€7) who were on waitlists for liver transplantation for hepatocellular carcinoma, received up to 48 weeks of sofosbuvir (400 mg) and ribavirin before liver transplantation. The primary end point was the proportion of patients with HCV-RNA levels less than 25 IU/mL at 12 weeks after transplantation among patients with this HCV-RNA level at their last measurement before transplantation.ResultsSixty-one patients received sofosbuvir and ribavirin, and 46 received transplanted livers. The per-protocol efficacy population consisted of 43 patients who had HCV-RNA level less than 25 IU/mL at the time of transplantation. Of these 43 patients, 30 (70%) had a post-transplantation virologic response at 12 weeks, 10 (23%) had recurrent infection, and 3 (7%) died (2 from nonfunction of the primary graft and 1 from complications of hepatic artery thrombosis). Of all 61 patients given sofosbuvir and ribavirin, 49% had a post-transplantation virologic response. Recurrence was related inversely to the number of consecutive days of undetectable HCV RNA before transplantation. The most frequently reported adverse events were fatigue (in 38% of patients), headache (23%), and anemia (21%).ConclusionsAdministration of sofosbuvir and ribavirin before liver transplantation can prevent post-transplant HCV recurrence. ClinicalTrials.gov: NCT01559844
Ledipasvir and Sofosbuvir Plus Ribavirin for Treatment of HCV Infection in Patients With Advanced Liver Disease
BACKGROUND & AIMS: There are no effective and safe treatments for chronic hepatitis C virus (HCV) infection of patients who have advanced liver disease.
METHODS: In this phase 2, open-label study, we assessed treatment with the NS5A inhibitor ledipasvir, the nucleotide polymerase inhibitor sofosbuvir, and ribavirin in patients infected with HCV genotypes 1 or 4. Cohort A enrolled patients with cirrhosis and moderate or severe hepatic impairment who had not undergone liver transplantation. Cohort B enrolled patients who had undergone liver transplantation: those without cirrhosis; those with cirrhosis and mild, moderate, or severe hepatic impairment; and those with fibrosing cholestatic hepatitis. Patients were assigned randomly (1:1) to receive 12 or 24 weeks of a fixed-dose combination tablet containing ledipasvir and sofosbuvir, once daily, plus ribavirin. The primary end point was sustained virologic response at 12 weeks after the end of treatment (SVR12).
RESULTS: We enrolled 337 patients, 332 (99%) with HCV genotype 1 infection and 5 (1%) with HCV genotype 4 infection. In cohort A (nontransplant), SVR12 was achieved by 86%-89% of patients. In cohort B (transplant recipients), SVR12 was achieved by 96%-98% of patients without cirrhosis or with compensated cirrhosis, by 85%-88% of patients with moderate hepatic impairment, by 60%-75% of patients with severe hepatic impairment, and by all 6 patients with fibrosing cholestatic hepatitis. Response rates in the 12-Â and 24-week groups were similar. Thirteen patients (4%) discontinued the ledipasvir and sofosbuvir combination prematurely because of adverse events; 10 patients died, mainly from complications related to hepatic decompensation.
CONCLUSION: The combination of ledipasvir, sofosbuvir, and ribavirin for 12 weeks produced high rates of SVR12 in patients with advanced liver disease, including those with decompensated cirrhosis before and after liver transplantation. ClinTrials.gov: NCT01938430
Rare coding variants in PLCG2, ABI3, and TREM2 implicate microglial-mediated innate immunity in Alzheimer's disease
We identified rare coding variants associated with Alzheimerâs disease (AD) in a 3-stage case-control study of 85,133 subjects. In stage 1, 34,174 samples were genotyped using a whole-exome microarray. In stage 2, we tested associated variants (P<1Ă10-4) in 35,962 independent samples using de novo genotyping and imputed genotypes. In stage 3, an additional 14,997 samples were used to test the most significant stage 2 associations (P<5Ă10-8) using imputed genotypes. We observed 3 novel genome-wide significant (GWS) AD associated non-synonymous variants; a protective variant in PLCG2 (rs72824905/p.P522R, P=5.38Ă10-10, OR=0.68, MAFcases=0.0059, MAFcontrols=0.0093), a risk variant in ABI3 (rs616338/p.S209F, P=4.56Ă10-10, OR=1.43, MAFcases=0.011, MAFcontrols=0.008), and a novel GWS variant in TREM2 (rs143332484/p.R62H, P=1.55Ă10-14, OR=1.67, MAFcases=0.0143, MAFcontrols=0.0089), a known AD susceptibility gene. These protein-coding changes are in genes highly expressed in microglia and highlight an immune-related protein-protein interaction network enriched for previously identified AD risk genes. These genetic findings provide additional evidence that the microglia-mediated innate immune response contributes directly to AD development
Home and Online Management and Evaluation of Blood Pressure (HOME BP) using a digital intervention in poorly controlled hypertension: randomised controlled trial
Objective: The HOME BP (Home and Online Management and Evaluation of Blood Pressure) trial aimed to test a digital intervention for hypertension management in primary care by combining self-monitoring of blood pressure with guided self-management. Design: Unmasked randomised controlled trial with automated ascertainment of primary endpoint. Setting: 76 general practices in the United Kingdom. Participants: 622 people with treated but poorly controlled hypertension (>140/90 mm Hg) and access to the internet. Interventions: Participants were randomised by using a minimisation algorithm to self-monitoring of blood pressure with a digital intervention (305 participants) or usual care (routine hypertension care, with appointments and drug changes made at the discretion of the general practitioner; 317 participants). The digital intervention provided feedback of blood pressure results to patients and professionals with optional lifestyle advice and motivational support. Target blood pressure for hypertension, diabetes, and people aged 80 or older followed UK national guidelines. Main outcome measures: The primary outcome was the difference in systolic blood pressure (mean of second and third readings) after one year, adjusted for baseline blood pressure, blood pressure target, age, and practice, with multiple imputation for missing values. Results: After one year, data were available from 552 participants (88.6%) with imputation for the remaining 70 participants (11.4%). Mean blood pressure dropped from 151.7/86.4 to 138.4/80.2 mm Hg in the intervention group and from 151.6/85.3 to 141.8/79.8 mm Hg in the usual care group, giving a mean difference in systolic blood pressure of â3.4 mm Hg (95% confidence interval â6.1 to â0.8 mm Hg) and a mean difference in diastolic blood pressure of â0.5 mm Hg (â1.9 to 0.9 mm Hg). Results were comparable in the complete case analysis and adverse effects were similar between groups. Within trial costs showed an incremental cost effectiveness ratio of ÂŁ11 ($15, âŹ12; 95% confidence interval ÂŁ6 to ÂŁ29) per mm Hg reduction. Conclusions: The HOME BP digital intervention for the management of hypertension by using self-monitored blood pressure led to better control of systolic blood pressure after one year than usual care, with low incremental costs. Implementation in primary care will require integration into clinical workflows and consideration of people who are digitally excluded. Trial registration: ISRCTN13790648
A novel Alzheimer disease locus located near the gene encoding tau protein
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordAPOE Δ4, the most significant genetic risk factor for Alzheimer disease (AD), may mask effects of other loci. We re-analyzed genome-wide association study (GWAS) data from the International Genomics of Alzheimer's Project (IGAP) Consortium in APOE Δ4+ (10 352 cases and 9207 controls) and APOE Δ4- (7184 cases and 26 968 controls) subgroups as well as in the total sample testing for interaction between a single-nucleotide polymorphism (SNP) and APOE Δ4 status. Suggestive associations (P<1 Ă 10-4) in stage 1 were evaluated in an independent sample (stage 2) containing 4203 subjects (APOE Δ4+: 1250 cases and 536 controls; APOE Δ4-: 718 cases and 1699 controls). Among APOE Δ4- subjects, novel genome-wide significant (GWS) association was observed with 17 SNPs (all between KANSL1 and LRRC37A on chromosome 17 near MAPT) in a meta-analysis of the stage 1 and stage 2 data sets (best SNP, rs2732703, P=5·8 Ă 10-9). Conditional analysis revealed that rs2732703 accounted for association signals in the entire 100-kilobase region that includes MAPT. Except for previously identified AD loci showing stronger association in APOE Δ4+ subjects (CR1 and CLU) or APOE Δ4- subjects (MS4A6A/MS4A4A/MS4A6E), no other SNPs were significantly associated with AD in a specific APOE genotype subgroup. In addition, the finding in the stage 1 sample that AD risk is significantly influenced by the interaction of APOE with rs1595014 in TMEM106B (P=1·6 Ă 10-7) is noteworthy, because TMEM106B variants have previously been associated with risk of frontotemporal dementia. Expression quantitative trait locus analysis revealed that rs113986870, one of the GWS SNPs near rs2732703, is significantly associated with four KANSL1 probes that target transcription of the first translated exon and an untranslated exon in hippocampus (Pâ€1.3 Ă 10-8), frontal cortex (Pâ€1.3 Ă 10-9) and temporal cortex (Pâ€1.2 Ă 10-11). Rs113986870 is also strongly associated with a MAPT probe that targets transcription of alternatively spliced exon 3 in frontal cortex (P=9.2 Ă 10-6) and temporal cortex (P=2.6 Ă 10-6). Our APOE-stratified GWAS is the first to show GWS association for AD with SNPs in the chromosome 17q21.31 region. Replication of this finding in independent samples is needed to verify that SNPs in this region have significantly stronger effects on AD risk in persons lacking APOE Δ4 compared with persons carrying this allele, and if this is found to hold, further examination of this region and studies aimed at deciphering the mechanism(s) are warranted
Applications of piezoresponse force microscopy in materials research: from inorganic ferroelectrics to biopiezoelectrics and beyond
Piezoresponse force microscopy (PFM) probes the mechanical deformation of a sample in response to an electric field applied with the tip of an atomic force microscope. Originally developed more than two decades ago to study ferroelectric materials, this technique has since been used to probe electromechanical functionality in a wide range of piezoelectric materials including organic and biological systems. Piezoresponse force microscopy has also been demonstrated as a useful tool to detect mechanical strain originating from electrical phenomena in non-piezoelectric materials. Parallelling advances in analytical and numerical modelling, many technical improvements have been made in the last decade: switching spectroscopy PFM allows the polarisation switching properties of ferroelectrics to be resolved in real space with nanometric resolution, while dual ac resonance tracking and band excitation PFM have been used to improve the signal-to-noise ratio. In turn, these advances have led to increasingly large multidimensional data sets containing more complete information on the properties of the sample studied. In this review, PFM operation and calibration are described, and recent advances in the characterisation of electromechanical coupling using PFM are presented. The breadth of the systems covered highlights the versatility and wide applicability of PFM in fields as diverse as materials engineering and nanomedicine. In each of these fields, combining PFM with complementary techniques is key to develop future insight into the intrinsic properties of the materials as well as for device applications.Science Foundation IrelandSwiss National Science Foundatio
Sources of dissolved and particulate organic material in Loch Vale watershed, Rocky Mountain National Park,
Abstract. The sources of both dissolved organic carbon (DOC) and particulate organic carbon (POC) to an alpine (Sky Pond) and a subalpine lake (The Loch) in Rocky Mountain National Park were explored for four years. The importance of both autochthonous and allochthonous sources of organic matter differ, not only between alpine and subalpine locations, but also seasonally. Overall, autochthonous sources dominate the organic carbon of the alpine lake, while allochthonous sources are a more significant source of organic carbon to the subalpine lake. In the alpine lake, Sky Pond, POC makes up greater than one third of the total organic matter content of the water column, and is related to phytoplankton abundance. Dissolved organic carbon is a product of within-lake activity in Sky Pond except during spring snowmelt and early summer (May-July), when stable carbon isotope ratios suggest a terrestrial source. In the subalpine lake, The Loch, DOC is a much more important constituent of water column organic material than POC, comprising greater than 90% of the spring snowmelt organic matter, and greater than 75% of the organic matter over the rest of the year. Stable carbon isotope ratios and a very strong relation of DOC with soluble Al(lt ) indicate DOC concentrations are almost entirely related to flushing of soil water from the surrounding watershed during spring snowmelt. Stable carbon isotope ratios indicate that, for both lakes, phytoplankton is an important source of DOC in the winter, while terrestrial material of plant or microbial origin contributes DOC during snowmelt and summer
The CD34+CD38neg population is significantly increased in haemopoietic cell expansion cultures in serum-free compared to serum-replete conditions: Dissociation of phenotype and function
Expansion of haemopoietic stem cells is proposed to combat graft failure in adult recipients following cord blood (CB) transplantation. Cultures are traditionally performed in medium containing FCS, but to transfer expansion to the clinic, 'good manufacturing practice' (GMP) standards are required. This study evaluated expansion cultures in culture bags and serum-free (SF) conditions, to comply with GMP, by analysing subpopulations of CD34+ cells, colony-forming cells (CFC) and long-term culture initiating cells (LTC-IC). CD34+ cell analysis has previously been used to measure clonogenic capacity and the CD34+CD38neg surface pheno-type to measure primitive cell numbers. In this study, comparison of expansion in serum-replete medium with that in SF conditions demonstrated a lack of expression of CD38 on CD34+ cells in the absence of serum. These findings must be considered in clinical studies using in vitro expansion in SF conditions, and the CD34+CD38neg phenotype should not be used to confirm maintenance, or expansion, of primitive progenitor cells