Bose-Einstein correlations of same-sign charged pions in the forward region in pp collisions at √s=7 TeV

Bose-Einstein correlations of same-sign charged pions, produced in protonproton collisions at a 7 TeV centre-of-mass energy, are studied using a data sample collected by the LHCb experiment. The signature for Bose-Einstein correlations is observed in the form of an enhancement of pairs of like-sign charged pions with small four-momentum difference squared. The charged-particle multiplicity dependence of the Bose-Einstein correlation parameters describing the correlation strength and the size of the emitting source is investigated, determining both the correlation radius and the chaoticity parameter. The measured correlation radius is found to increase as a function of increasing charged-particle multiplicity, while the chaoticity parameter is seen to decreas

Study of prompt D0 meson production in pPb collisions at √sNN=5 TeV

Production of prompt D0 mesons is studied in proton-lead and lead-proton collisions recorded at the LHCb detector at the LHC. The data sample corresponds to an integrated luminosity of 1.58±0.02 nb−1 recorded at a nucleon-nucleon centre-of-mass energy of √sNN=5 TeV. Measurements of the differential cross-section, the forward-backward production ratio and the nuclear modification factor are reported using D 0 candidates with transverse momenta less than 10 GeV/c and rapidities in the ranges 1.5 < y ∗ < 4.0 and −5.0 < y ∗ < −2.5 in the nucleon-nucleon centre-of-mass system.S

Prompt and nonprompt J/ψ production and nuclear modification in pPb collisions at s_NN=8.16 TeV

The production of J/ψ mesons is studied in proton-lead collisions at the centre-of-mass energy per nucleon pair sNN=8.16 TeV with the LHCb detector at the LHC. The double differential cross-sections of prompt and nonprompt J/ψ production are measured as a function of the J/ψ transverse momentum and rapidity in the nucleon–nucleon centre-of-mass frame. Forward-to-backward ratios and nuclear modification factors are determined. The results are compared with theoretical calculations based on collinear factorisation using nuclear parton distribution functions, on the colour glass condensate or on coherent energy loss models.</p

Observation of the Doubly Charmed Baryon Ξ++cc

A highly significant structure is observed in the $\Lambda_c^+K^-\pi^+\pi^+$ mass spectrum, where the $\Lambda_c^+$ baryon is reconstructed in the decay mode $pK^-\pi^+$. The structure is consistent with originating from a weakly decaying particle, identified as the doubly charmed baryon $\Xi_{cc}^{++}$. The difference between the masses of the $\Xi_{cc}^{++}$ and $\Lambda_c^+$ states is measured to be $1334.94 \pm 0.72 (\mathrm{stat}) \pm 0.27 (\mathrm{syst}~\mathrm{MeV}/c^2$, and the $\Xi_{cc}^{++}$ mass is then determined to be $3621.40 \pm 0.72 (\mathrm{stat}) \pm 0.27 (\mathrm{syst} \pm 0.14 \, (\Lambda_c^+)~\mathrm{MeV}/c^2$, where the last uncertainty is due to the limited knowledge of the $\Lambda_c^+$ mass. The state is observed in a sample of proton-proton collision data collected by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.7 $\mathrm{fb}^{-1}$, and confirmed in an additional sample of data collected at 8 TeV.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2017-018.htm

Real Life Data on Efficacy and Safety of Topical NGF Eye Drops (Cenegermin)

Background Topical NGF eye drops (Cenegermin) were approved in 2015 as an orphan drug for the treatment of neurotrophic keratopathy (NK). The active substance Cenegermin is a recombinant form of human NGF (nerve growth factor). Objectives Presentation of efficacy and safety of Cenegermin for use in patients in an university real-life setting. Material and Methods Retrospective study at the Koln University Eye Hospital from 2017 to 2019 with n = 11 eyes. Average follow-up was 13.5 +/- 7.1 months. Reasons for treatment were neurotrophic keratopathy stage II and III, clinically mostly in combination with corneal neovascularization. Results Seven eyes with a NK II and 4 eyes with a NK III with a median observation period of 13.6 months (range 1.2-20.3 months) from a total of 11 patients were included. The median patient age was 42.8 +/- 23.6 years (range 18-75 years). Before the start of therapy, the median erosion area measured 3.1 +/- 1.4 x 1.9 +/- 1.1 mm and the median ulcer area had a size of 2.3 +/- 1.1 x 2.1 +/- 0.8 mm. After the start of therapy with Cenegermin (application 6x/day), the epithelial defect closed in all 11 study eyes (100%) within 4-12 weeks (mean: 49 d +/- 9 d). In 9 out of 10 patients (90%) pre-existing corneal neovascularization regressed significantly (p <0.001). Before the start of therapy, a value in the Luneau test of 2.9 +/- 1.9 (minimum 1/6, maximum 4/6) was found and rose to a median value of 4.2 +/- 1.7 (minimum 2(6, maximum 6/6) after 18 months (p = 0.015). Therapy with Cenegermin had no long-term effect on intraocular pressure: the pressure ranged between 13.2 +/- 4.1 mmHg (minimum 8 mmHg, maximum 21 mmHg). Under therapy with NGF eye drops, 67% of the patients, after an initial decrease, showed a long-term improvement in visual acuity (BSCVA) from 0.72 +/- 0.31 to 0.46 +/- 0.29 logMAR after 18 months (p = 0.005). Relapses in form of a corneal erosion in the long-term follow-up were observed in only one eye. One patient had to stop therapy because of local pain, no other local and systemic side effects were observed. Conclusion This real-life series on the use of Cenegermin in a university context shows a good effectiveness of the substance for epithelial closure in various underlying diseases (100% within 12 weeks). There is a long-term improvement in vision and corneal sensitivity. Larger real-life cohorts with various underlying diseases should follow

Intensified Early Postoperative Topical Steroids Do Not Influence Endothelial Cell Density After Descemet Membrane Endothelial Keratoplasty Combined With Cataract Surgery (Triple-DMEK)

Purpose:To investigate the effect of intensified postoperative topical steroid therapy after Descemet membrane endothelial keratoplasty combined with cataract surgery (Triple-DMEK) on postoperative endothelial cell density (ECD).Methods:This comparative clinical study with historical controls was conducted at a tertiary hospital, specialized in corneal surgery. Patients undergoing DMEK or Triple-DMEK are included prospectively in the Cologne DMEK Database. Until April 2014, first week's postoperative standard therapy for lamellar keratoplasties was prednisolone acetate eye drops 1% applied 5x daily. After April 2014, first week's postoperative standard therapy changed to prednisolone acetate eye drops 1% applied hourly. We compared 75 consecutive eyes before (group 1) with 75 consecutive eyes after the change of therapy regimen (group 2). Patients received ECD analysis 3 and 6 months after surgery.Results:ECD of grafts in group 1 before transplantation, and 3 months and 6 months after surgery was 2697 218, 1765 +/- 349, and 1703 +/- 432 cells/mm(2), respectively. ECD of grafts in group 2 was 2696 +/- 267, 1737 +/- 450, and 1694 +/- 482 cells/mm(2), respectively. Over 3 and 6 months, ECD in group 1 decreased by 35% +/- 13% and 38% +/- 18%, respectively. In group 2, ECD decreased by 36% +/- 16% and 38% +/- 16%, respectively. Neither absolute numbers nor decrease in ECD differed significantly between groups 1 and 2 at any time point (all P > 0.60).Conclusions:Intensified early postoperative topical steroid therapy during the first postoperative week does not stabilize ECD, nor does it have a toxic effect on endothelial cells during a follow-up of 6 months

Intraoperative Optical Coherence Tomography (MI-OCT) for the Treatment of Corneal Dystrophies

Background The surgical treatment of corneal dystrophies develops rapidly as the use of lamellar corneal grafting techniques continue. While penetrating keratoplasty was the gold standard for treating a variety of dystrophies a few years ago, the affected layers of the cornea can, nowadays, be selectively replaced or ablated using laser technology. Of particular importance for these methods is optical coherence tomography, which has recently been integrated into surgical microscopes (MI-OCT). Methods Literature overview from PubMed and Google.scholar.de supplemented with own imaging data. Results The MI-OCT enables the intraoperative real-time monitoring of different ophthalmic surgical procedures, such as deep anterior lamellar keratoplasty, Descemets membrane endothelial keratoplasty, as well as minimally-invasive procedures, such as phototherapeutic keratectomy. In addition, it enables an evaluation of the cornea, but also of structures of the anterior chamber, in situations in which the cornea, for example, is clouded by an edema. Conclusion Microscope-integrated, intraoperative optical coherence tomography (MI-OCT) represents a useful supplement to the normal surgical microscope. It is superior to the sole surgical microscope, especially in already severely clouded corneas, and represents a sensible supplement, especially for novel lamellar transplantation procedures. Prospective randomized trials are necessary to increase safety and efficacy when using MI-OCT for different indications

Effect of corneal collagen crosslinking on subsequent deep anterior lamellar keratoplasty (DALK) in keratoconus

The purpose was to investigate the impact of ultraviolet light corneal collagen crosslinking (UV-CXL) on the success rate and clinical outcome of subsequent deep anterior lamellar keratoplasty (DALK) in eyes with keratoconus (KC). Medical records of 101 consecutive eyes with KC scheduled for big-bubble DALK surgery were screened retrospectively for details of previously performed UV-CXL, as well as intra- and postoperative complications of DALK surgery. Main outcome measures were intraoperative success rates (big-bubble formation, conversion to penetrating keratoplasty (PK)), postoperative complications, best corrected visual acuity (BCVA), endothelial cell density (ECD), and central corneal thickness (CCT) within 18 months of follow-up. Out of the 101 KC eyes, eight eyes (7.9%) had a history of previous UV-CXL. Surgical failure, defined as conversion to PK due to macroperforation, occurred in 17 eyes (16.8%) of 93 eyes without and in none with previous UV-CXL (P < .001). Failure to achieve a big-bubble occurred in 37 eyes (40.2%) without previous UV-CXL and in two eyes (25%) with previous UV-CXL. Microperforations of Descemet's membrane were observed in ten eyes (20.7%) without and in 14 eyes (15.2%) with previous UV-CXL (P = .16). No significant differences could be detected for either the postoperative complication rate (P ae .18) or the clinical outcome parameters at 18 months follow-up, including BCVA, ECD and CCT (P ae .08) for eyes with or without UV-CXL. In DALK surgery, prior UV-CXL does not seem to affect the rate of intra- or postoperative complications, the success rate, or its clinical outcome

Outcome of Descemet Membrane Endothelial Keratoplasty Using Corneas from Donors >= 80 Years of Age

PURPOSE: The purpose of this study was to investigate whether corneas from donors Z80 years old are suitable for Descemet membrane endothelial keratoplasty (DMEK). DESIGN: Retrospective, comparative, interventional case series. METHODS: Records of 1,765 consecutive DMEKs were reviewed and matched with corresponding donor tissue data. Older donors (>= 80 years of age) were compared to younger donors ( = 80 to 94 years of age, seem to produce comparable mid-term functional results following DMEK surgery compared to younger donors. The use of corneas from donors aged >= 80 for DMEK surgery may therefore be a promising approach to counteract global donor shortage. ((C) 2019 Elsevier Inc. All rights reserved.