37 research outputs found
Fully differential W' production and decay at next-to-leading order in QCD
We present the fully differential production and decay of a W' boson, with
arbitrary vector and axial-vector couplings, to any final state at
next-to-leading order in QCD. We demonstrate a complete factorization of
couplings at next-to-leading order in both the partial width of the W' boson,
and in the full two-to-two cross section. We provide numerical predictions for
the contribution of a W' boson to single-top-quark production, and separate
results based on whether the mass of the right-handed neutrino (nu_R) is light
enough for the leptonic decay channel to be open. The single-top-quark analysis
will allow for an improved direct W' mass limit of 525-550 GeV using data from
run I of the Fermilab Tevatron. We propose a modified tolerance method for
estimating parton distribution function uncertainties in cross sections.Comment: 23 pages, revtex3, 13 ps fig
Systems genetics identifies a role for Cacna2d1 regulation in elevated intraocular pressure and glaucoma susceptibility
Glaucoma is a multi-factorial blinding disease in which genetic factors play an important role. Elevated intraocular pressure is a highly heritable risk factor for primary open angle glaucoma and currently the only target for glaucoma therapy. Our study helps to better understand underlying genetic and molecular mechanisms that regulate intraocular pressure, and identifies a new candidate gene, Cacna2d1, that modulates intraocular pressure and a promising therapeutic, pregabalin, which binds to CACNA2D1 protein and lowers intraocular pressure significantly. Because our study utilizes a genetically diverse population of mice with kno
Cross-ancestry genome-wide association analysis of corneal thickness strengthens link between complex and Mendelian eye diseases
Central corneal thickness (CCT) is a highly heritable trait associated with complex eye diseases such as keratoconus and glaucoma. We perform a genome-wide association meta-analysis of CCT and identify 19 novel regions. In addition to adding support for known connective tissue-related pathways, pathway analyses uncover previously unreported gene sets. Remarkably, >20% of the CCT-loci are near or within Mendelian disorder genes. These included FBN1, ADAMTS2 and TGFB2 which associate with connective tissue disorders (Marfan, Ehlers-Danlos and Loeys-Dietz syndromes), and the LUM-DCN-KERA gene complex involved in myopia, corneal dystrophies and cornea plana. Using index CCT-increasing variants, we find a significant inverse correlation in effect sizes between CCT and keratoconus (r =-0.62, P = 5.30 Ă 10-5) but not between CCT and primary open-angle glaucoma (r =-0.17, P = 0.2). Our findings provide evidence for shared genetic influences between CCT and keratoconus, and implicate candidate genes acting in collagen and extracellular matrix regulation
Female patients with ankylosing spondylitis: analysis of the impact of gender across treatment studies
TIMP-1 promotes VEGF-induced neovascularization in the retina
Proteolysis of vascular basement membranes
and surrounding extracellular matrix is a critica1 early
step in neovascularization. It requires alteration of the
balance between matrix metalloproteinases (MMPs) and
proteins that bind to and inactivate MMPs, tissue
inhibitors of metalloproteinases (TIMPs). TIMP-1 has
been demonstrated to inhibit neovascularization in chick
chorioallantoic membranes. However, TIMP-1 has also
been shown to either promote or inhibit cell proliferation
and migration in different settings. To determine whether
genetic alteration of the MMPDIMP-1 ratio would alter
retinal neovascularization, we crossed mice that express
vascular endothelial growth factor (VEGF) in
photoreceptors with TIMP-1-deficient mice or mice that
overexpress TIMP-1. Compared to VEGF transgenepositive/
TIMP-1-sufficient mice, VEGF transgenepositive1TIMP-
1-deficient mice showed smaller
neovascular lesions. There was also no difference
between the two groups of mice in the appearance of the
neovascularization by light or electron microscopy.
Compound VEGFITIMP-1 transgenic mice had
increased expression of both VEGF and TIMP-1 in the
retina, and had more neovascularization than mice that
had increased expression of VEGF alone. These gainand
loss-of-function data suggest that alteration of the
TIMP-1MMP ratio modulates retinal neovascularization
in a complex manner and not simply by altering the proteolytic activity and thereby invasiveness of
endothelial cells
Recommended from our members
Gene expression variation in the adult human retina
Despite evidence that differences in gene expression levels contribute significantly to phenotypic variation across individuals, there has been only limited effort to study gene expression variation in human tissue. To characterize expression variation in the normal human retina, the authors utilized a custom retinal microarray to analyze 33 normal retinas from 19 donors, aged 29 to 90 years. Statistical models were designed to separate and quantify biological and technical sources of variation, including age, gender, eye laterality, gene function, and age-by-gender interaction. Although the majority of the 9406 genes analyzed showed relatively stable expression across different donors (for an average gene the expression level value of 95 out of a 100 individual fell within a 1.23-fold range), 2.6% of genes showed significant donor-to-donor variation, with a false discovery rate of 10%. The mean expression ratio standard deviation was 0.15 ± 0.8, log
2, with a range of 0.09 to 0.99. Genes selectively expressed in photoreceptors showed higher expression variation than other gene classes. Gender, age, and other donor-specific factors contributed significantly to the expression variation of multiple genes, and groups of genes with age- or gender-associated expression pattern were identified. These findings show that a significant fraction of gene expression variation in the normal human retina is attributable to identifiable biologic factors. The greater expression variability of many genes central to retinal function (including photoreceptor-specific gene) may be partially explained by the dynamics of the vision process, and raises the possibility that photoreceptor gene expression levels may contribute to phenotypic diversity across normal adult retinas. Additionally, as such diversity may result in different levels of disease susceptibility, exploring its sources may provide insights into the pathogenesis of retinal disease.âHans E. Grossniklau
Alcohol dehydrogenase: An autoantibody target in patients with alcoholic liver disease
The link between alcohol consumption and liver disease is not direct and several factors including autoimmunity to hepatocyte components have been implicated. We have previously identified alcohol dehydrogenase (ADH) as an autoantigen in autoimmune liver disease and in a proportion of patients with alcoholic liver disease. The aim of the present study is to investigate the association between the presence of anti-ADH antibodies, alcohol consumption and severity of liver damage in alcoholic patients. The presence of antibodies to human ADH beta2 and horse ADH was investigated in 108 patients with documented history of alcohol consumption and alcohol related liver disease, 86 being active alcohol abusers and 22 on sustained alcohol withdrawal, 39 with non-alcohol related disease and 22 normal subjects. Antibodies to either ADH form were more frequently detected in active alcohol abusers (55/86, 64%) than in patients on sustained alcohol withdrawal longer than 6 months (1/8, 13 %, P < 0.005), HBV infection (2/8, 25 %, P=0.03), non-alcohol related disease (9/29, 23 %, P < 0.0001) and in normal controls (3/22, 14 %, P < 0.0001); were more frequent in patients with cirrhosis than in those with steatosis (26/34, 76 % vs 34/64, 53 %, P=0.02); and were associated with elevated levels of ALT (anti-ADH beta2, P < 0.05), immunoglobulin A (P < 0.05) and gamma-glutamyl transpeptidase (P=0.01). Anti-ADH antibody positive serum samples were able to inhibit the enzymatic activity of ADH. These findings suggest that anti-ADH antibodies may be triggered by alcohol consumption and act as a disease activity marker in alcoholic liver disease