Membrane lipid composition of Carnobacterium maltaromaticum CNCM I-3298, a highly cryoresistant lactic bacterium.

The growing consumption of fermented products has led to an increasing demand for lactic acid bacteria (LAB), especially for LAB tolerant to freezing/thawing conditions. Carnobacterium maltaromaticum is a psychrotrophic and freeze-thawing resistant lactic acid bacterium. The membrane is the primary site of damage during the cryo-preservation process and requires modulation to improve cryoresistance. However, knowledge about the membrane structure of this LAB genus is limited. We presented here the first study of the membrane lipid composition of C. maltaromaticum CNCM I-3298 including the polar heads and the fatty acid compositions of each lipid family (neutral lipids, glycolipids, phospholipids). The strain CNCM I-3298 is principally composed of glycolipids (32%) and phospholipids (55%). About 95% of glycolipids are dihexaosyldiglycerides while less than 5% are monohexaosyldiglycerides. The disaccharide chain of dihexaosyldiglycerides is composed of α-Gal(1-2)-α-Glc chain, evidenced for the first time in a LAB strain other than Lactobacillus strains. Phosphatidylglycerol is the main phospholipid (94%). All polar lipids are exceptionally rich in C18:1 (from 70% to 80%). Regarding the fatty acid composition, C. maltaromaticum CNCM I-3298 is an atypical bacterium within the genus Carnobacterium due to its high C18:1 proportion but resemble the other Carnobacterium strains as they mostly do not contain cyclic fatty acids.

Sequential intracorneal ring segment implantation followed by transepithelial phototherapeutic keratectomy and corneal cross-linking.

PURPOSE: To evaluate the safety and visual outcomes of intrastromal corneal ring segment (ICRS) implantation followed by transepithelial phototherapeutic keratectomy (te-PTK) and corneal cross-linking (CXL) in patients with mild keratoconus. METHODS: Patients with mild keratoconus and contact lens intolerance who underwent sequential ICRS implantation followed by phototherapeutic keratectomy and corneal CXL between April 2015 and July 2018 were retrospectively included in the study. Refractive and visual outcomes, satisfaction questionnaire and complications were recorded at the last follow-up (mean 9.5 months postoperatively). RESULTS: Twenty eyes of 17 patients were enrolled, including 5 women and 15 men. The mean time between the two procedures was 16 months. Based on values before the first procedure and 9.5 months after the second procedure, significant improvements were noted in uncorrected distance visual acuity (UDVA) (0.80±0.35 logMAR vs. 0.46±0.38 logMAR), corrected distance visual acuity (CDVA) (0.38±0.23 logMAR vs. 0.13±0.16 logMAR), maximal K (56.11±4 diopters [D] vs. 50.6±3.56 D), mean K (51.87±3.43 D vs. 48.45±2.91 D), cylinder (7.99±3.94 D vs. 4.23±3.49 D), and spherical equivalent (-3.84±3.36 D vs. -0.99±2.15 D) (P<0.01). Among the outcomes, we noted 5 (25%) superficial corneal scarring (haze); 75% of eyes gained>=1 logMAR line of CDVA. In all, 94.5% of patients reported that they were satisfied with their outcomes. CONCLUSION: Combining ICRS implantation followed by te-PTK and corneal CXL appears to be a safe and effective approach for improving visual outcomes and quality of life in keratoconus patients.

Screening for retinopathy of prematurity by telemedicine in a tertiary level neonatal intensive care unit in France: Review of a six-year period.

PURPOSE: To analyze the prevalence and risk factors for retinopathy of prematurity (ROP) and severe (treatment-requiring) ROP. METHODS: A retrospective study was conducted in a level III neonatal unit in Bordeaux, France, from 2009 to 2015. Four hundred and nineteen preterm infants who were screened for ROP exclusively by RetCam were included. RESULTS: ROP of any degree was diagnosed in 27.68% of infants. Stages 1, 2, 3 and 4 ROP was found in 44%, 46%, 9% and 1% of subjects, respectively. No stage 5 ROP was observed. 28/419 infants (6.6%) were treated exclusively with laser photocoagulation. No intravitreal anti-VEGF injections or surgical treatments were performed. No infants born at>31 weeks or with BW>1110g required ROP treatment. On multivariate analysis, risk factors for ROP development were low birth weight, low gestational age at birth, high duration of invasive mechanical ventilation, shock or use of vasopressors. On multivariate analysis, risk factors for severe, treatment-requiring ROP were male gender, gestational age≤27 weeks and Apgar score at 5minutes≤7. CONCLUSION: In our 6-year series, ROP was successfully identified on screening exclusively by telemedicine, and no surgical treatment was required. This study identifies known ROP risk factors, but the Apgar score at 5minutes as a risk factor for severe ROP requires further studies in order to be confirmed.

[Refractive outcomes and precision in toric intraocular lens alignment using an automated alignment system]. / Résultats réfractifs et évaluation de la précision du positionnement des implants toriques à l'aide d'un système d'alignement automatisé.

PURPOSE: To compare precision in toric intraocular lens (TIOL) alignment and refractive outcomes between an intraoperative automated digital marker system and the conventional manual-ink marking. MATERIALS AND METHODS: Prospective single center study including consecutive patients undergoing uneventful cataract surgery with corneal astigmatism greater than 1 diopter. Total corneal astigmatism was measured using a placido-dual Scheimpflug system (GalileiG4®, Ziemer). Acrysof® SN6AT (Alcon) TIOL's were implanted, and patients were divided into 2 groups, the digital group (Verion®, Alcon) and the ink-marking group (Pendular marker, AMO). Mean error in TIOL axis, visual acuity and residual astigmatism were analyzed at 3 days, one month and 6 months after surgery. RESULTS: In total, 45 eyes of 30 patients were included (n=25 digital group, n=20 ink-marking group). The mean preoperative total corneal astigmatism was 1.71±0.53 diopters. At one month, there was a significantly lower mean average error in TIOL axis in the digital group compared to the ink-marking group (2.6±2.3° and 6.4±2.8° respectively, P=0.009). At 6months, these results remained statistically significant. Mean residual astigmatism was 0.7±0.4 diopters at one month, without significant difference between the two groups (P=0.9). The rate of misalignment less than or equal to 5° was 86 % (n=25) in the digital group and 63 % (n=20) in the ink-marking group (P=0.05). CONCLUSION: Intraoperative digital marker system is associated with better TIOL alignment accuracy and better reproducibility than the manual ink-marking method.

High mass and spatial resolution mass spectrometry imaging of Nicolas Poussin painting cross section by cluster TOF-SIMS.

The painting Rebecca and Eliezer at the Well, which hangs in the Fitzwilliam Museum, Cambridge, UK, is possibly one of the last figure painting executed by Nicolas Poussin at the very end of his life and is usually dated to the early 1660s. In this perspective special feature, Philippe Walter, Alain Brunelle and colleagues give new insights on the artist's working methods by a careful stateof-the-art imaging ToF-SIMS study of one sample taken on the edge of the painting. This approach allowed for the identification of the pigments used in the painting, their nature and components and those of the ground and preparatory layers, with the identification of the binder(s) and possible other additions of organic materials such as glue. This study paves the way to a wider use of ToF-SIMS for the analysis of ancient cultural heritage artefacts. Dr. Walter is the Director of the Molecular and Structural Archeology Laboratory (Université Pierre et Marie Curie, Paris, France). Dr. Brunelle is Head of the Mass Spectrometry Laboratory at the Institut de Chimie des Substances Naturelles (CNRS, Gif-sur-Yvette, France). Their long standing collaboration has led to several seminal publications on the analysis of ancient artefacts by mass spectrometry.

Reproducibility of single-pass donor DSAEK tissue preparation with the MORIA single-use microkeratome.

PURPOSE: To assess the reproducibility of single-pass cutting for preparation of ultra-thin (≤120µm) donor cornea grafts in Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: All consecutive patients of DSAEK performed using the MORIA One Use microkeratome (MORIA, Antony, France) in between June 2014 and August 2015. Patient and donor central corneal thickness (CTT), microkeratome head, remaining stromal bed thickness (RSBT), number of cut and graft thickness at 1 month and 6 months postoperatively were recorded in this single-center prospective study. RESULTS: The mean preoperative donor graft CCT was 569.0±45.1µm and the mean donor endothelial graft CCT immediately after the cut was 116.5±28.7µm. At 1 month postoperatively, the mean CCT was 102.8±35.9µm. At 6 months, the mean CCT was 89.4±26.2µm. In all eyes, the mean CCT decreased from the post-cut (116.5±28.7µm) to the last visit (89.4±26.2µm) (P<0.01) due to in vivo deturgesence of the graft. We obtained 77.5% ultra-thin DSAEK immediately after the cut, 77.5% at 1 month and 89.8% after 6 months. CONCLUSION: Single-pass technique with the MORIA One Use microkeratome offers safe and reproducible DSAEK tissue preparation and allows achieving ultra-thin DSAEK in 89.8% of cases.

[Efficacy of corneal cross-linking for the treatment of keratoconus]. / Efficacité du cross-linking du collagène cornéen pour le traitement du kératocône.

Keratoconus (KC) is a complex disease whose pathophysiology is only partially understood. The priority in management is to halt the progression of corneal deformation as soon as possible in the course of KC disease. Corneal cross-linking (CXL) is at present the only dedicated treatment for this purpose. Its biochemical mechanism of action leads to changes in the viscoelastic properties of the cornea induced by matrix bonding and renewal of keratocytes. The effect of CXL is difficult to quantify when measured in in-vivo conditions because of a lack of consistent tools adapted for clinical practice. Nevertheless, a large amount of evidence has been collected so far confirming the positive action of CXL on corneal structural reinforcement, and numerous studies have demonstrated significant efficacy in halting progression of KC with long-term follow-up. Published studies, however, are of relatively low scientific power given the great heterogeneity of the disease and the numerous associated biases in evaluation. The purpose of this paper is to summarize the consistent evidence of efficacy of CXL and to justify its role in our therapeutic armamentarium for management of progressive KC.

[Evaluation of corneal biomechanical properties in glaucoma and control patients by dynamic Scheimpflug corneal imaging technology]. / Évaluation des propriétés biomécaniques de la cornée de patients glaucomateux et témoins par la technologie dynamique Scheimpflug de visualisation cornéenne.

PURPOSE: To compare corneal biomechanical properties measured with Corvis Scheimpflug technology (Corvis ST) between a group of patients with chronic open-angle glaucoma and a group of control patients. DESIGN: Prospective observational case-control study. METHODS: This study enrolled 56 right eyes of 56 patients (G1 [chronic open-angle glaucoma] n=37/G2 [control] n=19). Each patient underwent measurement of corneal biomechanical properties by dynamic Scheimpflug (Corvis ST) camera and the Ocular Response Analyser (ORA), then a measurement of intraocular pressure (IOP) by Goldmann applanation tonometry (GAT) and measurement of central corneal thickness (CCT) by optical coherence tomography during the same visit, by a single clinician. The parameters determined by Corvis ST are: Corvis IOP (IOP Corvis ST), the corneal deformation amplitude (CDA), corneal velocity, the time at highest concavity (TIME CONCAV), the lengths of applanation and their corresponding applanation time. Those studied by ORA are: compensated IOP (IOPcc), non-compensated IOL (IOPg), corneal hysteresis (CH) and corneal resistance factor (CRF). RESULTS: IOP measured on all patients by Corvis ST was positively correlated to GAT (Spearman r=0.569, P<0.001) and PIOcc (Spearman r=0.531, P<0.001). After adjusting for age effect, CCT and GAT, the CDA was significantly lower in G1 than in G2, respectively 1.10 ± 0.12 mm and 1.15 ± 0.10mm (P<0.001). The TIME CONCAV is significantly shorter in G1 than in G2, respectively 16.88 ± 0.63 ms and 17.11 ± 0.29 ms, P=0.029. CH was significantly lower in G1 (G1: 9.58 ± 1.94 than G2: 10.89 ± 2.16, P=0.026). CONCLUSIONS: This study showed differences in corneal biomechanical properties between glaucoma and control patients. The cornea of glaucoma patients appears less deformable.

[Keratoconus]. / Kératocône.

Keratoconus is a slowly progressive, non-inflammatory disorder of the eye characterized by thinning and protrusion of the cornea. Typically diagnosed in the patient's adolescent years, keratoconus may lead to substantial distortion of vision primarily from irregular astigmatism and myopia, and secondarily from corneal scarring. The classic histopathologic features include breaks in Bowman's layer and thinning of the corneal stroma. The etiology of keratoconus remains unclear. Form fruste keratoconus shows little progression, and has become known due to videotopographic analysis; it is very important to rule out in refractive surgery candidates. Treatment begins first and foremost with contact lenses, progressing to surgery as contact lens intolerance develops, with the goal of stabilization, including: cross-linking, intrastromal corneal ring segments and corneal transplantation.

[Neovascular invasion of the endothelio-descemetic interface occurring after deep anterior lamellar keratoplasty]. / Invasion néovasculaire de l'interface endothélio-descemetique au décours d'une kératoplastie lamellaire antérieure profonde.

INTRODUCTION: The endothelio-descemetic interface (EDI) of a deep anterior lamellar keratoplasty (DALK) may become the locus of a neovascular proliferation. Bevacizumab (Avastin) is an antiangiogenic alternative available for curative treatment in deep corneal neovascularization. OBSERVATION: We report the case of a 49-year-old woman who had received two arcuate relaxing incisions for high astigmatism after DALK. She developed graft rejection associated with significant neovascular stromal invasion in the EDI of the graft-host interface. Two subconjunctival injections of bevacizumab 1 month apart as well as thermocauterization of the feeding vessel were necessary and effective. No recurrence has been observed after 2 years of follow-up. DISCUSSION: Corneal neovascularization can be a cause of DALK rejection. A combination of anti-antiangiogenic and physical methods may abort graft rejection and permanently restore graft function.

VUV photoionization of gas phase adenine and cytosine: a comparison between oven and aerosol vaporization.

We studied the single photon ionization of gas phase adenine and cytosine by means of vacuum ultraviolet synchrotron radiation coupled to a velocity map imaging electron∕ion coincidence spectrometer. Both in-vacuum temperature-controlled oven and aerosol thermodesorption were successfully applied to promote the intact neutral biological species into the gas phase. The photoion yields are consistent with previous measurements. In addition, we deduced the threshold photoelectron spectra and the slow photoelectron spectra for both species, where the close to zero kinetic energy photoelectrons and the corresponding photoions are measured in coincidence. The photoionization close and above the ionization energies are found to occur mainly via direct processes. Both vaporization techniques lead to similar electronic spectra for the two molecules, which consist of broadbands due to the complex electronic structure of the cationic species and to the possible contribution of several neutral tautomers for cytosine prior to ionization. Accurate ionization energies are measured for adenine and cytosine at, respectively, 8.267 ± 0.005 eV and 8.66 ± 0.01 eV, and we deduce precise thermochemical data for the adenine radical cation. Finally, we performed an evaluation and a comparison of the two vaporization techniques addressing the following criteria: measurement precision, thermal fragmentation, sensitivity, and sample consumption. The aerosol thermodesorption technique appears as a promising alternative to vaporize large thermolabile biological compounds, where extended thermal decomposition or low sensitivity could be encountered when using a simple oven vaporization technique.

[AcrySof® Toric (SN60T) intraocular lens implantation: refractive predictibility and aberrometric impact of decentration]. / Prédictibilité réfractive et retentissement aberrométrique du décentrement des implantations toriques du pseudophaque de type SN60T-AcrySof®.

PURPOSE: To evaluate refractive outcomes of toric intraocular lens (IOL) implantation with a detailed analysis of decentration and its effect on aberrometry. METHODS: This retrospective study enrolled 19 eyes implanted with SN60T AcrySof(®) Toric (Alcon - USA) IOL's. Spherocylindric correction was studied in depth by the Alpins method, and retro-illumination images were used to analyze the alignment of the IOL with its intended axis. IOL decentration as well as its aberrometric impact were evaluated with a strict, novel protocol. RESULTS: Three months postoperatively, uncorrected distance visual acuity was greater or equal to 20/40 in 94.74% of cases, postoperative subjective cylinder was less or equal to 0.5 D in 68.42% of eyes, with a mean index of success of 0.24. Mean error of toric IOL alignment was 5.68° (0 to 14). Mean IOL decentration was 0.78 mm (0 to 1.78) with a mean coma and trefoil of 0.18 µ (0.06 to 0.33) and 0.19 µ (0.05 to 0.51), respectively. The larger the IOL decentration, the higher the optical aberrations were. CONCLUSION: Toric intraocular lens implantation is an effective, safe and predictable method of spherocylindrical correction during cataract surgery, with a refractive accuracy similar to that of LASIK in the treatment of astigmatism in young patients. IOL decentration produces optical aberrations including coma and trefoil, which interfere with visual performance.

[Epidemiological aspects of keratoconus in children]. / Aspects épidémiologiques du kératocône chez l'enfant.

PURPOSE: To study the epidemiological aspects of keratoconus in children. METHODS: We conducted a retrospective study of patients with keratoconus diagnosed prior to age 15 or after age 27. Age, gender, reason for consultation, ethnicity, personal and family history, allergic history, eye rubbing, optical and surgical treatment, and educational and professional background were identified. Data from each group were compared by Chi(2) testing. RESULTS: Forty-nine children and 167 adults were studied. The majority of patients were Caucasian. Children were more frequently male (P=0.0386) and allergic (67.35% versus 47.31% in adults, P=0.0136). Eye rubbing was found in 91.84% of children and 70.06% of adults (P=0.002). In total, 12.24% of children had a family history of keratoconus versus 14.97% of adults (P=0.6324). Totally, 68.09% of children were fitted with rigid contact lenses versus 15.66% of adults (P=0.0909). In all, 80.5% of surgically treated children underwent corneal collagen cross-linking versus 30% of adults. DISCUSSION: Younger patients are more often male, with women being older at time of diagnosis. Allergy is a frequent association. However, 25% of children in the general population display allergies. In any event, eye rubbing is a common feature, whether due to itching or induced ametropia. CONCLUSION: In order to detect the disease early, corneal topography could be performed routinely in all young, allergic boys with a history of eye rubbing and recent-onset corneal astigmatism.

[Correction of irregular astigmatism with intracorneal ring segments]. / Correction des astigmatismes irréguliers par anneaux intra cornéens.

Management of irregular astigmatism with intracorneal rings segments is an intrastromal additive technique developed initially for myopia but eventually popularized for keratoconus and post LASIK ectasia. ICR's are indicated for rigid contact lens intolerance, as an alternative to corneal transplantation. The mechanism of action is complex and involves biomechanical changes leading to a centering and a flattening of the ectasia. The surgical procedure has become much easier thanks to the use of femtosecond lasers. Individualized implantation strategies, based on each patient's topographic and tomographic pattern, are constantly evolving. Patients' refraction and vision are usually improved in more than 70% of cases. Complications remain very rare. Intracorneal ring segments can often be combined with other types of keratoplasty, usually in a sequential fashion, so as to optimize functional results.