A Unique Case of Autoimmune Retinopathy Associated with Anti-Alpha-Enolase Antibodies

Background. We report a case of autoimmune retinopathy associated with anti-alpha-enolase antibodies with unique manifestations. Methods. A case report. Results. A 30-year-old male experienced recurrent, primarily peripheral visual field disturbances and minimal photopsia, with interval symptom resolution. Fundus changes subsequently developed in areas corresponding to the previous visual field symptoms. Electroretinogram showed bilaterally symmetric abnormalities of light-adapted responses and suggested loss of photoreceptor function. Only anti-alpha-enolase antibodies were detected on Western blot. Our patient noted cutaneous symptoms at the time of both episodes of visual symptoms, but not in the interim. Biomicroscopy revealed subtle small reddish spots in areas of the peripheral retina corresponding to the areas of the patient's visual field where he noted symptoms. To our knowledge these reddish spots have not been reported in autoimmune retinopathy and may clinically support in vitro and in vivo evidence that anti-alpha-enolase antibodies may target photoreceptors. Conclusions. Our patient demonstrates some unique features adding to the known characteristics of autoimmune retinopathy associated with anti-alpha-enolase antibodies. As more cases are reported, further understanding of the features and pathophysiology of this rare condition will hopefully be elucidated

Electroretinographic and clinicopathologic correlations of retinal dysfunction in infantile neuronal ceroid lipofuscinosis (infantile Batten disease)

Infantile neuronal ceroid lipofuscinosis (INCL) is an autosomal recessive disease that results from deficiency of palmitoyl-protein thioesterase-1 (PPT1). INCL leads to retinal blindness, neurodegeneration, and early death. We studied the clinical features and electroretinogram (ERG) in three patients and histopathologic and immunofluorescence analyses of the retina in the third patient, who died at 3 years 2 months of age. The ERGs for the 2 youngest patients (ages 1.7 and 2.3 years) showed normal scotopic bright flash a-wave amplitudes with severe loss of b-wave (electronegative ERG), indicating dysfunction at or proximal to the photoreceptor inner segments. The third patient at 2.9 years of age showed subnormal a-wave amplitudes and even greater loss of b-wave amplitudes. Histopathology revealed reduced cell numbers in all retinal layers, including the inner nuclear layer (INL), and a central epiretinal membrane. Autofluorescent lipofuscin granules were present in all neuronal cell types in the retina. Cones and rods in the parafoveal area were labeled with a cone cytoplasmic marker, mAb 7G6, and anti-rhodopsin, respectively, and had extremely short outer segments. The periphery showed better preservation but photoreceptor outer segments were short. Immunofluorescence revealed degenerate rods and cones throughout the retina with better preservation in the periphery. Autofluorescent lipofuscin was found in all cell types, including cone inner segments, to a greater degree than seen in normal ageing. The ERG findings support the existence early in the disease of a relative pre- or post-synaptic block of effective neurotransmission from photoreceptor inner segments to the second order bipolar neurons

Search for supersymmetry in the multijet and missing transverse momentum final state in pp collisions at 13 TeV

A search for new physics is performed based on all-hadronic events with large missing transverse momentum produced in proton-proton collisions at sqrt(s)=13 TeV. The data sample, corresponding to an integrated luminosity of 2.3 inverse femtobarns, was collected with the CMS detector at the CERN LHC in 2015. The data are examined in search regions of jet multiplicity, tagged bottom quark jet multiplicity, missing transverse momentum, and the scalar sum of jet transverse momenta. The observed numbers of events in all search regions are found to be consistent with the expectations from standard model processes. Exclusion limits are presented for simplified supersymmetric models of gluino pair production. Depending on the assumed gluino decay mechanism, and for a massless, weakly interacting, lightest neutralino, lower limits on the gluino mass from 1440 to 1600 GeV are obtained, significantly extending previous limits

Search for associated production of dark matter with a Higgs boson decaying to bbˉb\bar{b} or γγ\gamma\gamma at s\sqrt{s} = 13 TeV

A search for dark matter is performed using events with large missing transverse momentum and a Higgs boson decaying either to a pair of bottom quarks or to a pair of photons. The data from proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC, correspond to an integrated luminosity of 2.3 inverse-femtobarns. Results are interpreted in the context of a Z'-two-Higgs-doublet model, where a high-mass resonance Z' decays into a pseudoscalar boson A and a CP-even scalar Higgs boson, and the A decays to a pair of dark matter particles. No significant excesses are observed over the background prediction. Combining results from the two decay channels yields exclusion limits in the signal cross section in the m[Z']-m[A] phase space. The observed data exclude, for Z' coupling strength g[Z'] = 0.8 and m[A] = 300 GeV for example, the Z' mass range of 600 to 1860 GeV. This is the first result on a search for dark matter produced in association with a Higgs boson that includes constraints on h to gamma-gamma obtained at sqrt(s) = 13 TeV

Measurement of double-differential cross sections for top quark pair production in pp collisions at s=8\sqrt{s} = 8 TeV and impact on parton distribution functions

Normalized double-differential cross sections for top quark pair $(t\bar{t})$ production are measured in pp collisions at a centre-of-mass energy of 8 TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 19.7 fb$^{-1}$. The measurement is performed in the dilepton $e^{\pm} \mu^{\mp}$ final state. The $t\bar{t}$ cross section is determined as a function of various pairs of observables characterizing the kinematics of the top quark and $t\bar{t}$ system. The data are compared to calculations using perturbative quantum chromodynamics at next-to-leading and approximate next-to-next-to-leading orders. They are also compared to predictions of Monte Carlo event generators that complement fixed-order computations with parton showers, hadronization, and multiple-parton interactions. Overall agreement is observed with the predictions, which is improved when the latest global sets of proton parton distribution functions are used. The inclusion of the measured ttbar cross sections in a fit of parametrized parton distribution functions is shown to have significant impact on the gluon distribution

Particle-flow reconstruction and global event description with the CMS detector

The CMS apparatus was identified, a few years before the start of the LHC operation at CERN, to feature properties well suited to particle-flow (PF) reconstruction: a highly-segmented tracker, a fine-grained electromagnetic calorimeter, a hermetic hadron calorimeter, a strong magnetic field, and an excellent muon spectrometer. A fully-fledged PF reconstruction algorithm tuned to the CMS detector was therefore developed and has been consistently used in physics analyses for the first time at a hadron collider. For each collision, the comprehensive list of final-state particles identified and reconstructed by the algorithm provides a global event description that leads to unprecedented CMS performance for jet and hadronic τ decay reconstruction, missing transverse momentum determination, and electron and muon identification. This approach also allows particles from pileup interactions to be identified and enables efficient pileup mitigation methods. The data collected by CMS at a centre-of-mass energy of 8TeV show excellent agreement with the simulation and confirm the superior PF performance at least up to an average of 20 pileup interactions

Measurement of the top quark mass in the dileptonic ttˉt\bar{t} decay channel using the mass observables Mbl,MT2,M_{bl}, M_{T2}, and MblvM_{blv} in pppp collisions at s=8\sqrt{s} = 8 TeV

A measurement of the top quark mass ($M_{t}$) in the dileptonic ttbar decay channel is performed using data from proton-proton collisions at a center-of-mass energy of 8 TeV. The data was recorded by the CMS experiment at the LHC and corresponding to an integrated luminosity of 19.7$\pm$ 0.5$^{-1}$. Events are selected with two oppositely charged leptons $(\ell = e, \mu)$ and two jets identified as originating from b quarks. The analysis is based on three kinematic observables whose distributions are sensitive to the value of $M_{t}$. An invariant mass observable, $M_{bl}$, and a 'stransverse mass' observable, $M_{T2}$, are employed in a simultaneous fit to determine the value of $M_{t}$ and an overall jet energy scale factor (JSF). A complementary approach is used to construct an invariant mass observable, $M_{bl\nu},$ that is combined with $M_{T2}$ to measure $M_{t}$. The shapes of the observables, along with their evolutions in $M_{t}$ and JSF, are modeled by a nonparametric Gaussian process regression technique. The sensitivity of the observables to the value of $M_{t}$ is investigated using a Fisher information density method. The top quark mass is measured to be 172.22 $\pm$ 0.18 (stat)$^{+0.89}_{-0.93}$ (syst) GeV

Search for vector-like light-flavor quark partners in proton-proton collisions at sqrt(s)=8 TeV

A search is presented for heavy vector-like quarks (VLQs) that couple only to light quarks in proton-proton collisions at sqrt(s) = 8 TeV at the LHC. The data were collected by the CMS experiment during 2012 and correspond to an integrated luminosity of 19.7 inverse femtobarns. Both single and pair production of VLQs are considered. The single-production search is performed for down-type VLQs (electric charge of magnitude 1/3), while the pair-production search is sensitive to up-type (charge of magnitude 2/3) and down-type VLQs. Final states with at least one muon or one electron are considered. No significant excess over standard model expectations is observed, and lower limits on the mass of VLQs are derived. The lower mass limits range from 400 to 1800 GeV, depending on the single-production cross section and the VLQ branching fractions B to W, Z, and Higgs bosons. When considering pair production alone, VLQs with masses below 845 GeV are excluded for B(W) = 1.0, and below 685 GeV for B(W) = 0.5, B(Z) = B(H) = 0.25. The results are more stringent than those previously obtained for single and pair production of VLQs coupled to light quarks

Particle-flow reconstruction and global event description with the CMS detector

The CMS apparatus was identified, a few years before the start of the LHC operation at CERN, to feature properties well suited to particle-flow (PF) reconstruction: a highly-segmented tracker, a fine-grained electromagnetic calorimeter, a hermetic hadron calorimeter, a strong magnetic field, and an excellent muon spectrometer. A fully-fledged PF reconstruction algorithm tuned to the CMS detector was therefore developed and has been consistently used in physics analyses for the first time at a hadron collider. For each collision, the comprehensive list of final-state particles identified and reconstructed by the algorithm provides a global event description that leads to unprecedented CMS performance for jet and hadronic tau decay reconstruction, missing transverse momentum determination, and electron and muon identification. This approach also allows particles from pileup interactions to be identified and enables efficient pileup mitigation methods. The data collected by CMS at a centre-of-mass energy of 8 TeV show excellent agreement with the simulation and confirm the superior PF performance at least up to an average of 20 pileup interactions