New insights into the genetic etiology of Alzheimer's disease and related dementias

Characterization of the genetic landscape of Alzheimer's disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/'proxy' AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Natural History of Non-Alcoholic Fatty Liver Disease: A Study With Paired Liver Biopsies

Background: Although there is unequivocal evidence for progression of nonalcoholic steatohepatitis (NASH) to cirrhosis, there is uncertainty with regard to the progression to nonalcoholic fatty liver (NAFL) and NASH. Aims: We investigated the rate of progression to NASH and advanced fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) and assessed the factors associated with such progression. Methods: Histological assessment was performed in 36 patients with NAFLD with paired liver biopsies (≥1 year apart; median, 3.8 years; range, 1–10.33 years). NASH Clinical Research Network (NASH CRN) criteria were used to assess NAFLD Activity Score (NAS). Results: At baseline, 26 (72%) patients had NAFL and 10 (28%) patients had NASH. At follow-up, 27% NAFL progressed to NASH (NAS score ≥5), and 50% of patients with NASH no longer met the criteria of NASH. Fibrosis progressed in 15 (42%), regressed in 9 (25%), and remained stable in 12 (33%) patients overall. Thirty-five percent of patients with NAFL had fibrosis progression. The incidence of type 2 diabetes mellitus (T2DM) was higher in patients with NASH versus NAFL (40% vs. 27%). Both at the time of baseline and follow-up, liver biopsies, composite models of noninvasive scores such as Fibrosis-4 (FIB-4) score and NAFLD fibrosis score, and ratio of aspartate aminotransferase (AST) to alanine aminotransferase (ALT) were all significantly higher in progressors than in nonprogressors. Conclusions: NAFLD is a dynamic liver disease with varying degrees of progression and regression. T2DM was strongly associated with fibrosis progression. Noninvasive fibrosis scores such as AST/ALT ratio, FIB-4 score, and NAFLD fibrosis score can identify those at risk of fibrosis progression

Accuracy of noninvasive fibrosis scoring systems in african american and white patients with nonalcoholic fatty liver disease

OBJECTIVES: Nonalcoholic fatty liver disease fibrosis score (NFS), fibrosis-4 (FIB-4) score, aspartate aminotransferase (AST)-to-platelet ratio index (APRI) score, and AST-alanine aminotransferase (ALT) ratio are noninvasive fibrosis scoring systems for the staging of liver fibrosis in patients with chronic liver disease. METHODS: In a large cohort of patients with nonalcoholic fatty liver disease, we compared AST-ALT ratio, NFS, FIB-4 score, and APRI score in predicting advanced fibrosis (defined as fibrosis stage ‡ 3) in histologically confirmed African American (AA) and white patients. We identified 907 patients: 677 (74.6%) white and 230 (25.3%) AA patients with nonalcoholic fatty liver disease. RESULTS: Of the 907 patients, 115 (12.8%) patients had advanced fibrosis (stages 3 and 4) in the total cohort: 6 (2.6%) AAs, and 109 (16.2%) whites. In AAs, the area under the receiver operating characteristic (area under the curve) for predicting advanced fibrosis was 0.58 by NFS, 0.86 by APRI score, 0.77 by FIB-4 score, and 0.65 by AST-ALT ratio. In whites, the area under the receiver operating characteristic for predicting advanced fibrosis was 0.82 by NFS, 0.82 by APRI score, 0.88 by FIB-4 score, and 0.76 by AST-ALT ratio. In the AA population, NFS \u3e 0.675, FIB-4 score \u3e 2.67, and APRI score \u3e 1.5 each has a negative predictive value of 98%, whereas the negative predictive values in whites are 91%, 88%, and 85%, respectively. DISCUSSION: Noninvasive fibrosis scoring systems can reliably exclude advanced fibrosis in both AAs and whites and have acceptable discriminatory ability to predict advanced fibrosis in whites. The utility of noninvasive fibrosis scoring systems in predicting advanced fibrosis in AAs needs further validation in a larger multicenter cohort

Charm production in 400 GeV/c proton-emulsion interactions

5032 proton-emulsion interactions at 400 GeV/c momentum have been carefully scrutinized for production and decay of charged charm particles. In order to detect these decays, shower tracks from 3056 stars have been followed to a maximum length of 1 mm and those from 1976 stars up to 2 mm. A total of 23 three-prong charm-like candidates have been recorded in the forward cone. The background due to γ-overlap on a shower track, trident/pseudo-trident production and secondary interactions is estimated to be 15. Attributing the signal of 8 events to Λc+ and assuming the branching ratio of Λc+ → 3 prong to be 0.6 and tΛc to be 10-13 sec we obtain the production cross section to be 106±39µb/nucleon. Out of these 8 events one example of semileptonic decay of Λc+ is seen

Effect of a quadrivalent meningococcal ACWY glycoconjugate or a serogroup B meningococcal vaccine on meningococcal carriage: an observer-blind, phase 3 randomised clinical trial

BACKGROUND: Meningococcal conjugate vaccines protect individuals directly, but can also confer herd protection by interrupting carriage transmission. We assessed the effects of meningococcal quadrivalent glycoconjugate (MenACWY-CRM) or serogroup B (4CMenB) vaccination on meningococcal carriage rates in 18-24-year-olds.METHODS: In this phase 3, observer-blind, randomised controlled trial, university students aged 18-24 years from ten sites in England were randomly assigned (1:1:1, block size of three) to receive two doses 1 month apart of Japanese Encephalitis vaccine (controls), 4CMenB, or one dose of MenACWY-CRM then placebo. Participants were randomised with a validated computer-generated random allocation list. Participants and outcome-assessors were masked to the treatment group. Meningococci were isolated from oropharyngeal swabs collected before vaccination and at five scheduled intervals over 1 year. Primary outcomes were cross-sectional carriage 1 month after each vaccine course. Secondary outcomes included comparisons of carriage at any timepoint after primary analysis until study termination. Reactogenicity and adverse events were monitored throughout the study. Analysis was done on the modified intention-to-treat population, which included all enrolled participants who received a study vaccination and provided at least one assessable swab after baseline. This trial is registered with ClinicalTrials.gov, registration number NCT01214850.FINDINGS: Between Sept 21 and Dec 21, 2010, 2954 participants were randomly assigned (987 assigned to control [984 analysed], 979 assigned to 4CMenB [974 analysed], 988 assigned to MenACWY-CRM [983 analysed]); 33% of the 4CMenB group, 34% of the MenACWY-CRM group, and 31% of the control group were positive for meningococcal carriage at study entry. By 1 month, there was no significant difference in carriage between controls and 4CMenB (odds ratio 1·2, 95% CI 0·8-1·7) or MenACWY-CRM (0·9, [0·6-1·3]) groups. From 3 months after dose two, 4CMenB vaccination resulted in significantly lower carriage of any meningococcal strain (18·2% [95% CI 3·4-30·8] carriage reduction), capsular groups BCWY (26·6% [10·5-39·9] carriage reduction), capsular groups CWY (29·6% [8·1-46·0] carriage reduction), and serogroups CWY (28·5% [2·8-47·5] carriage reduction) compared with control vaccination. Significantly lower carriage rates were also noted in the MenACWY-CRM group compared with controls: 39·0% (95% CI 17·3-55·0) carriage reduction for serogroup Y and 36·2% (15·6-51·7) carriage reduction for serogroup CWY. Study vaccines were generally well tolerated, with increased rates of transient local injection pain and myalgia in the 4CMenB group. No safety concerns were identified.INTERPRETATION: Although we detected no significant difference between groups at 1 month after vaccine course, MenACWY-CRM and 4CMenB vaccines reduced meningococcal carriage rates during 12 months after vaccination and therefore might affect transmission when widely implemented.<br/