Reproducible method for assessing the effects of blue light using in vitro human skin tissues.

INTRODUCTION: High-intensity visible light (HEV), also referred to as blue light, has a wavelength of 400-500 nm and accounts for approximately one-third of the visible light. Blue light is also emitted from electronic devices and artificial indoor lighting. Studies have shown that exposure of human skin cells to light emitted from electronic devices, even as short as 1 h, can cause an increase in reactive oxygen species (ROS), apoptosis and necrosis. Despite comprising a significant portion of the light spectrum, the effects of HEV light have not been studied as extensively. This is in part due to a lack of suitable in vitro testing methods. This work was conducted in order to develop a reproducible testing method for assessing the effects of blue light on the skin. METHODS: Testing was performed using a full thickness, 3D in vitro skin tissue model. Different exposure protocols were tested to (1) determine the biological effects of blue light on the skin and (2) to identify an appropriate exposure for routine testing of cosmetic materials that may protect the skin from blue light damage. Gene expression and protein biomarkers were measured using qPCR, ELISA and immunohistochemical (IHC) methods. RESULTS: Our work demonstrates that daily exposure to blue light produced dose-and-time-dependent changes in biomarkers associated with skin damage. Exposure to blue light for 6 h for 5 consecutive days (total intensity of 30 J/cm2 ) increased the expression of genes that regulate inflammation and oxidative stress pathways and decreased the expression of genes that maintain skin barrier and tissue integrity. Exposure to blue light significantly increased protein biomarkers associated with ageing, inflammation and tissue damage. IHC staining confirmed changes in collagen, filaggrin and NQO1 protein expression. Treatment with ascorbic acid inhibited the effects of blue light, demonstrating a role in protection from blue light. CONCLUSION: Our results showed that consistent blue light exposure produced skin damage via alterations in biological pathways that are associated with skin ageing. This work provides a new, reproducible in vitro testing method for assessing the effects of blue light on human skin using gene expression, protein ELISA and IHC staining.

INTRODUCTION: La lumière visible à haute énergie (VHE), également appelée lumière bleue, a une longueur d'onde de 400 à 500 nm et représente environ un tiers de la lumière visible. La lumière bleue est également émise par les appareils électroniques et l'éclairage intérieur artificiel. Des études ont montré que l'exposition des cellules cutanées humaines à la lumière émise par les appareils électroniques, même pour une période de seulement 1 h, peut entraîner une augmentation des dérivés réactifs de l'oxygène (DRO), de l'apoptose et de la nécrose. Bien qu'ils représentent une partie importante du spectre lumineux, les effets de la lumière VHE n'ont pas été étudiés aussi largement. Cela est en partie dû à un manque de méthodes de test in vitro appropriées. Ces travaux ont été réalisé afin de développer une méthode de test reproductible pour évaluer les effets de la lumière bleue sur la peau. MÉTHODES: Les tests ont été réalisés à l'aide d'un modèle de tissu cutané 3D in vitro de pleine épaisseur. Différents protocoles d'exposition ont été testés pour (1) déterminer les effets biologiques de la lumière bleue sur la peau et (2) identifier une exposition appropriée pour les tests de routine des produits cosmétiques susceptibles de protéger la peau des dommages causés par la lumière bleue. L'expression génique et les biomarqueurs protéiques ont été mesurés à l'aide des méthodes de PCR quantitative, de dosage par la méthode immuno-enzymatique ELISA et immunohistochimiques (IHC). RÉSULTATS: Nos travaux démontrent que l'exposition quotidienne à la lumière bleue a produit des modifications dépendantes de la dose et du temps dans les biomarqueurs associés aux lésions cutanées. L'exposition à la lumière bleue pendant 6 h au cours de 5 jours consécutifs (intensité totale de 30 J/cm2) a augmenté l'expression des gènes qui régulent l'inflammation et les voies du stress oxydatif, et a diminué l'expression des gènes qui maintiennent la barrière cutanée et l'intégrité tissulaire. L'exposition à la lumière bleue a significativement augmenté les biomarqueurs protéiques associés au vieillissement, à l'inflammation et aux lésions tissulaires. La coloration par IHC a confirmé les modifications de l'expression du collagène, de la filaggrine et de la protéine NQO1. Le traitement par acide ascorbique a inhibé les effets de la lumière bleue, démontrant un rôle dans la protection contre la lumière bleue. CONCLUSION: Nos résultats ont montré qu'une exposition continue à la lumière bleue produisait des lésions cutanées par le biais d'altérations des voies biologiques associées au vieillissement de la peau. Ces travaux fournissent une nouvelle méthode de test in vitro reproductible pour évaluer les effets de la lumière bleue sur la peau humaine à l'aide de l'expression des gènes, du test ELISA de détection de protéines et de la coloration IHC.

Disinfection mechanism of the photocatalytic activity of SnO2 thin films against Candida albicans, proposed from experimental and simulated perspectives.

Nosocomial infections are an important health problem and cause of complications and death in hospitalized patients. This problem should be solved from the preventive angle, avoiding the spread of infections by designing disinfection methods based on the photocatalytic activity of semiconductor materials such as tin oxide (SnO2). The antimicrobial activity of UV light was tested by using inoculation with Candida albicans ATCC10231 on SnO2 thin films and counting colony forming units (CFU). The interaction of UV light with SnO2 was analyzed by density functional theory (DFT) and the extension to the Hubbard model (DFT+U) schemes to predict the electron behavior at the subatomic level. After exposure to UV light, C. albicans showed a reduction of 36.5% in viable cells, and when SnO2 was included, cell viability was reduced by 60.2%. Measurements of the electronic structure obtained by the first-principle calculations under the DFT and DFT+U schemes showed that the O-p orbitals mediate the oxidation process in the bulk semiconductor. By including the surface effects when cleaving the (1 0 0) plane, the three orbitals O-p, Sn-p, and Sn-s are the mediators. SnO2 films are promising antimicrobial coatings because UV light has a synergic activity with thin films, resulting in faster disinfection.

Inactivation of Cronobacter sakazakii by blue light illumination and the resulting oxidative damage to fatty acids.

Blue light (BL) exerts an antimicrobial effect on pathogenic bacteria. It has been hypothesized that its bactericidal activity depends upon the generation of reactive oxygen species (such as anion superoxides) and the resultant cellular damage. However, some aspects of this hypothesis needed to be tested and investigated. Thus, the work conducted herein examined the molecular impact of BL treatment on Cronobacter sakazakii, an emerging foodborne pathogen. The results showed that BL exhibited an efficient bactericidal effect against C. sakazakii. Under a sublethal BL dose, both intracellular anion superoxides and malondialdehyde (a marker of oxidative stress) contents were increased gradually. Moreover, permeability of the outer membrane was increased by approximately 50%, indicating membrane damage. Further investigation revealed alterations to cellular fatty acid profiles, with a decrease and disappearance of unsaturated fatty acids, including C18:2, C16:1, and C18:1. These data indicate that bacterial lipids, especially unsaturated fatty acids, are important molecular targets of BL photo-oxidation. The transcriptional response of bacteria to BL was also studied, and it was found that three genes were upregulated, including genes encoding antioxidants. The current study contributes towards an improved understanding of the bactericidal mechanisms of BL and highlights the importance of lipid and membrane damage.

Improvement of the anti-proliferative activity of the peptide ERα17p in MCF-7 breast cancer cells using nanodiamonds.

Nanodiamonds (NDs) are emerging delivery systems with biomedical applications and interesting perspectives in oncology. Their use has been proposed to assist the internalization of anticancer drugs and to decrease administered drug doses. The pro-apoptotic peptide ERα17p, which is issued from the hinge/N-terminus parts of the AF2 region of the human estrogen receptor α (ERα), is active at a concentration of 10µM on breast cancer cells and particularly on those cancer cells that are ERα-positive. We have synthesized ND@ERα17p conjugates by physisorption of the cationic peptide ERα17p on the surface of anionic NDs. Resulting ND@ERα17p suspensions were characterized by far-UV electronic circular dichroism (ECD), dynamic light scattering (DLS) and zetametry. We then tested the anti-proliferative action of ND@ERα17p on ERα-positive MCF-7 breast carcinoma cells. ND@ERα17p allowed a decrease of the active concentration to 0.1nM (ND@ERα17p), revealing unambiguously that NDs could be used to improve the anti-proliferative action of this peptide. This preliminary study proposes a novel approach for enhancing the apoptotic action displayed by ERα17p, in the context of breast cancer.

[The use of social media modifies teenagers' sleep-related behavior]. / Nouveaux médias sociaux, nouveaux comportements de sommeil chez les adolescents.

OBJECTIVE: Modification of sleep behaviors in teenagers has been observed over the past 30years with a reduction in overall sleep time and an increasing number of teenagers suffering from sleep deprivation. Sleep deprivation is linked to physical problems such as obesity but also to change in performance at school and mood disorders. Changes have been associated with the use of screens, cell phones, Internet and social media. Use of screens has been shown to delay sleep onset and melatonin secretion and stimulation of wake systems by interaction with social media may exacerbate these effects. The links between the use of social media and sleep patterns have not been fully explored. Our study aimed to evaluate the effects of social media on teenagers' sleep and the impact of sleep deprivation. METHODOLOGY: As part of a sleep education program conducted in middle schools, teenagers from 6th to 9th grade were invited to complete an online questionnaire on sleep habits with teacher supervision and after parental consent. Outcome measures were sleep and wake times with estimated sleep duration in school (SP) and rest periods (RP), use of screens (computers, tablets, smartphones and video game consoles), the use of social media and impact on visual analogue scales of sleep quality, mood and daytime functioning. Students were divided into those with clear sleep deprivation (sleep time<6hours in SP) and those whose sleep time was in line with the National Sleep Foundations recommended sleep needs for teenagers (9hours or more). RESULTS: A total of 786 questionnaires were completed and 776 were exploitable. Four schools took part with 408/786 girls (64.2 %) and a mean age of 12.4±1.24. Internet access was almost universal (98.3 %), 85.2 % had cell phones and 42.7 % had a personal computer in their bedroom. Social media was used by 64.6 %. After dinner, 52.6 % spent more than an hour and 14.7 % spent more than 2hours in front of a screen. After bedtime, 51.7 % regularly used electronic devices of which 25.6 % had a screen-based activity (e.g. texts, social media, video games or television). During the night, some teens woke up to continue screen-based activities: 6.1 % in order to play online video games, 15.3 % to send texts and 11 % to use social media. Bedtimes were later in PR compared with PS (22h06±132 vs. 23h54±02; P<0.0001) as were wake times (7h06±36 vs. 10h06±102; P<0.0001). Sleep time was clearly longer in PR (10h12±126 P<0.0001) compared to PS. For students in 6th grade compared to 9th grade in sleep duration in SP decreased (8:55±90 vs. 7:25±93; P<0.0001), whereas sleep duration during RP was stable (10h08±118 vs. 10h08±90 P<0.029). No significant difference was found between girls and boys for sleep duration, sleep quality, performance during the day or mood. Sleep deprivation during the week (6hours or less) was less common in 6th graders 5 % vs. 15 % (P<0.0001). In sleep deprived teens compared to teens sleeping, the recommended ≥9hours, difficulties falling asleep were reported with 33 % vs. 9 % taking over an hour to fall asleep (P<0.0001) and difficulties getting up in the morning were more common (7.05±3.27 vs. 5.74±2.97; P=0.0003). Sleep deprivation had an effect on daytime performance: teenagers deprived of sleep were more likely to report a need to fight sleepiness, (5.93±3.24 vs. 2.84±2.44 P<0.0001) and had reduced energy during the day (6.21±2.86 vs. 7.77±2.07 P<0.0001). A negative effect on mood was evident: in sleep, deprived teenagers irritability (5.28±3.12 vs. 3.30±2.34; P<0.0001) and feelings of sadness (3.97±2.99 vs. 2.59±2.15; P=0.003) were more common. There was a clear association between sleep deprivation and access to screens and social media: sleep deprived teens were at more risk of nocturnal disruption with a higher prevalence of computers (67 % vs. 33 %; P<0.0001), cell phones (99 % vs. 80 %; P=0.0001) and smart phones (85 % vs. 66 %; P=0.0001) in their bedrooms. CONCLUSIONS: Access to social media and especially a cell phone in teenagers' bedrooms is associated with a reduction in sleep time during the school week with negative effects on daily functioning and mood which increases with increasing age. Education about use of social media and sleep for teenagers needs to start early as modifications in sleep and evening use of screens was present on our population from 11years on and to involve parents as setting parent controlled bedtimes has been shown to increase teenage sleep time.

[Light sources usable by the plastic surgeon in the absence of photographic studio]. / Sources lumineuses utilisables par le chirurgien plasticien en l'absence de studio photographique.

Medical photography is an important part of the medical file and is widely used in medical communication, especially in our discipline. His practice has to be the most standardized and reproducible as possible, which distinguishes it from artistic photography. Photography fix the light reflecting from a subject, so surgeon have to control of the light source in any environment. In the absence of dedicated studio, using external cobra or ring flashes with special diffusers allow the surgeon to have light sources adapted to the different conditions encountered in daily practice.

[Procedure for daylight methyl aminolevulinate photodynamic therapy to treat actinic keratoses]. / Modalités pratiques de traitement des kératoses actiniques par photothérapie dynamique topique en lumière du jour avec l'aminolévulinate de méthyle.

Actinic keratosis (AK), also known as solar keratosis or pre-cancerous keratosis, is frequently observed in areas of skin exposed to sunlight, particularly in light-skinned patients. In France, photodynamic therapy using red light (conventional PDT) and methylamino 5-levulinate (MAL) is indicated in the treatment of thin or non-hyperkeratotic and non-pigmented multiple AK lesions or large zones covered with AK lesions. It is well-known for its efficacy but also for its side effects, especially pain during illumination, which can limit its use. An alternative to PDT using natural daylight has recently been proposed to treat actinic keratosis lesions, and results in greater flexibility as well as significant reduction in pain. The lesions are prepared as for conventional PDT, with MAL cream being applied by the physician or the patient, after which they are exposed to natural daylight for 2hours. The lesions are then gently cleansed and protected from natural light for 24hours. This paper seeks to provide a precise description of the daylight PDT procedure for the treatment of AK.

[The circadian system in man: From the internal clock to melatonin secretion]. / À propos du système circadien chez l'homme : de l'horloge interne à la sécrétion de mélatonine.

The internal or biological clock which is located in the suprachiasmatic nuclei of the anterior hypothalamus is controlled by clock genes and environmental factors which are able to synchronize the clock to 24h. Rhythm desynchronization (shiftwork and nightwork, transmeridian flights, aging, some psychiatric diseases, blindness, intake of some drugs…) occurs when the internal clock does no longer work in harmony with the astronomical time i.e. our watch. The circadian system consists of three major elements, which are the clock, the retinohypothalamic tract and melatonin which is secreted by the pineal gland and considered as the arrow of the clock. Both light and melatonin present a phase response curve useful for the treatment of sleep circadian disorders.

[A cause of palatal necrosis not to ignore]. / Une cause de nécrose palatine à ne pas méconnaître.

We report a case of pseudotumoral nasal septum and hard palate perforation in a 42-years-old man. The diagnosis retained after differential diagnosis exclusion was necrotic midfacial lesion due to chronic inhalation of cocaine. This condition can mimic vasculitis, primary tumors and granulomatous infections. Differential diagnosis and pathophysiology of this condition will be discussed in this anatomo-clinical case.

[Stimuli-sensitive polymer systems]. / Systèmes polymères stimuli sensibles.

The polymers can be found in different forms in solution (particles, capsules, pseudo-micelles, hydrogels…) or on surface with important prospects in many field applications. These polymer systems are particularly very good candidates to entrap, transport and deliver an active substance in biomedical applications however with many limitations on control of release of a given target. The stimuli-sensitive polymers, also called smart or environmentally sensitive polymers, present physical or chemical changes under the action of small variations of an external stimulus. This signal acts as a stimulus which causes the change of conformation and/or solvation of the macromolecular chains by modifying their various interactions. The stimuli are classified into two broad categories: physical or external stimuli: temperature, mechanical stress, light, magnetic and electric fields; chemical and biochemical or internal stimuli: pH, ionic strength, chemical molecule (glucose, redox) or biochemical (enzymes, antigens…). The use of stimuli-sensitive pathway is widely used in the literature to enhance or trigger the release of an active compound. In this paper, we present the different stimuli addressing the theoretical aspects, polymers corresponding to these stimuli. Some examples illustrate these systems for the controlled release of active compounds.

[Blue light and intraocular lenses (IOLs): Beliefs and realities]. / Lumière bleue et implants intraoculaires : croyances et réalités.

The first intraocular lenses (IOLs) used for cataract surgery transmitted both ultraviolet (UV) radiation and visible light to the retina. Colorless UV-blocking IOLs were introduced and rapidly adopted in the 1980s. Yellow-tinted blue-blocking (also known as blue-filtering) IOLs were marketed in the early 1990s. Blue-blocking IOLs were intended to simulate age-related crystalline lens yellowing to reduce the cyanopsia that some patients experienced after cataract surgery. When blue-filtering IOLs were introduced in North America, however, blue-blocking chromophores were advocated as a way to protect patients from age-related macular degeneration (AMD) despite the lack of evidence that normal environmental light exposure causes AMD. The "blue light hazard" is a term that describes the experimental finding that acute, abnormally intense light exposures are potentially more phototoxic to the retina when short rather than long wavelengths are used. Thus, in brief exposures to intense light sources such as welding arcs, ultraviolet radiation is more hazardous than blue light, which is more hazardous than longer wavelength green or red light. International commissions have cautioned that the blue light hazard does not apply to normal indoor or outdoor light exposures. Nonetheless, the hazard is used for commercial purposes to suggest misleadingly that ambient environmental light can cause acute retinal phototoxicity and increase the risk of AMD. Very large epidemiological studies show that blue-blocking IOLs do not reduce the risk or progression of AMD. Additionally, blue-filtering IOLs or spectacles cannot decrease glare disability, because they decrease image and glare illuminance in the same proportion. Blue light is essential for older adults' scotopic photoreception needed to reduce the risk of nighttime falling and related injuries. It is also critical for circadian photoreception that is essential for good health, sleep and cognitive performance. Unfortunately, age-related pupillary miosis, retinal rod and ganglion cell photoreceptor degeneration and decreased outdoor activity all reduce the amount of healthful blue light available to older adults. Blue-restricting IOLs further reduce the available blue light at a time when older adults need it most. Patients and ophthalmologists are exposed to hypothesis-based advertisements for blue-filtering optical devices that suppress short wavelength light critical for vision in dim lighting and for good physical and mental health. Spectacle and intraocular lens selections should be based on scientific fact, not conjecture. Ideal IOLs should improve photoreception rather than limit it permanently. Practice efficiency, surgical convenience and physician-manufacturer relationships may eliminate a patient's opportunity to choose between colorless blue-transmitting IOLs and yellow-tinted, blue-restricting IOLs. Cataract surgeons ultimately determine whether their patients have the opportunity to make an informed choice about their future photoreception.

Efficacy and safety of intense pulsed light delivered by the C.STIM® for treatment of Meibomian gland dysfunction.

INTRODUCTION: Intense pulsed light (IPL) appears to be a promising treatment for Meibomian gland dysfunction (MGD), the most common cause of dry eye disease. C.STIM® is a new IPL device. We report the first safety and efficacy study in clinical practice. MATERIALS AND METHODS: Patients with moderate MGD treated with C.STIM® were included. Three IPL sessions were performed at D0, D15 and D45 with 4 shots per side (fluence of 8J/cm2). Clinical evaluation was performed at D0, D45 and M3 with several parameters: BUT, OSDI and Oxford scales, meibomian gland evaluation (morphology, quality and expressibility of meibum). The Lacrydiag® imaging device was used for objective evaluation of interferometry, meibography, tear meniscus height and NIBUT. The primary endpoint was the change in NIBUT between D0 and M3. Data collection was retrospective. Longitudinal analysis and a non-parametric linear mixed-effects model (R software) were used for statistical analysis. RESULTS: Thirty-five patients were included. NIBUT increased significantly between D0 and M3, with a mean difference of 2.6seconds (95% CI 2.0; 3.1, P<0.001). The other parameters studied also changed significantly, except for meibography (percentage of loss and morphology) and tear meniscus height. No adverse event was noted. CONCLUSION: C.STIM® appears safe and effective in the treatment of MGD, although a randomized controlled trial is needed to validate these results.

Optimized combined low level light therapy and intense pulsed light therapy for the treatment of dry eye syndrome caused by Meibomian glands dysfunction.

Dry eye syndrome (DES) is a common disease that can lead to ocular discomfort, reduced visual acuity and reduced quality of life. Meibomian Gland dysfunction plays an important role in most cases. To evaluate the effects of "EyeLight", a novel device delivering combined intense pulsed light (IPL) and low-level light therapy (LLLT), we conducted a retrospective chart review of patients refractory to conventional medical treatment who were treated with "EyeLight" therapy at Laser Vision, Lebanon. Each patient received between 2 to 5 treatment sessions. Clinical measurements were obtained before and after each session, including tear film breakup time (TBUT), ME-CHECK-meiboscale and the ME-CHECK questionnaire to determine the need for an additional session and to monitor progress. The same clinical evaluation was performed 3 to 5 weeks after the final treatment. A total of 52 eyes were included. A significant improvement in objective clinical signs was found, with an increase in TBUT from 6.98±1.41s. to 9.27±1.25s. (P<0.001) and a decrease in ME-CHECK-meiboscale (P<0.001). A reduction of severity level on the ME-CHECK-meiboscale classification was observed in 90%, along with a significant improvement in subjective clinical signs on the ME-CHECK questionnaire (P<0.001). No ocular or facial adverse events were noted. "EyeLight" treatment of 2 to 5 sessions depending on the severity of MGD in each eye showed an improvement in objective clinical signs and subjective symptoms and therefore appears to be an effective treatment for DES related to MGD refractory to conventional treatment.

[Efficacy of intense pulsed light therapy in the treatment of Meibomian gland dysfunction-related severe dry eye]. / Efficacité de la lumière pulsée dans le traitement des sécheresses oculaires sévères par dysfonctionnement meibomien.

INTRODUCTION: Dry eye syndrome caused by Meibomian gland dysfunction (MGD) is a common disease in the general population and impairs quality of life. Intense Pulsed Light (IPL) has mainly been used in dermatology for the treatment of skin disorders, and more recently for MGD-related dry eye. The objective of our study is to evaluate the efficacy and tolerability of IPL with the E-Eye® device (E-Swin, Houdan, France) in severe MGD-related dry eye patients. MATERIALS AND METHODS: This non-comparative study included 20 patients with MGD-related dry eye with a Break-Up Time (BUT)<10seconds, dry eye symptoms >30mm on a Visual Analog Scale (VAS), and failure of lid hygiene and artificial tears. Treatment consisted of 3 sessions of IPL on D0, D15, and D45 (5 flashes of 13J/cm2 per eye). The following parameters were assessed at each visit and at D75 : symptoms graded with a VAS and the Standard Patient Assessment of Eye Dryness questionnaire (SPEED), BUT, corneal fluorescein staining, Meibomian gland expression score, meibography, tear film lipid layer thickness by interferometry and the ocular scattering index by double-pass aberrometry (OQAS). Statistical analysis was performed on the eye most affected at baseline. RESULTS: We included 40 eyes of 20 patients, 15 female and 5 male, mean age 47±15 years (24 to 74 years). The symptoms rated by VAS were severe, averaging 69±25mm. After treatment, there was a statistically significant decrease in symptoms, with a 14mm VAS decrease (55±29mm at D75 versus 69mm at D0, P=0.048) and SPEED score of 3.4 (19.0±6mm versus 22.4±4.6, P=0.03). The number of expressible Meibomian gland ducts increased significantly (from 5.9 to 8.1, P=0.04), lid redness decreased (from 1.4 to 0.6, P=NS) and BUT improved (from 4.2 to 5.9, P=NS). Other parameters remained unchanged. Three patients (15%) complained of transient ocular burning after each treatment. CONCLUSION: IPL appears to be effective in improving signs and symptoms in patients with severe MGD-related dry eye, with a good safety profile. Its exact mechanism of action remains to be elucidated.

[Combined Intense Pulsed Light and low-level light therapy in the treatment of Meibomian gland dysfunction]. / Traitement combiné par lumière intense pulsée et thérapie par lumière de faible niveau dans le dysfonctionnement des glandes de Meibomius.

INTRODUCTION: Meibomian gland dysfunction (MGD) is the most common cause of dry eye syndrome. The goal of this study was to evaluate the efficacy of combined intense pulsed light (IPL) and low-level light therapy (LLLT) in symptomatic MGD. MATERIALS AND METHODS: This retrospective study analyzed data from 30 patients with MGD causing dry eye symptoms not relieved by medical therapy and managed with combined IPL and LLLT. The primary endpoint was the Ocular Score Disease Index (OSDI) score at 1 month and 1 year. Secondary endpoints were visual acuity, intraocular pressure, tear film break-up time, Schirmer's test, Oxford score, and infrared meibographic score at 1 month after the conclusion of treatment. RESULTS: The mean OSDI score decreased from 43±19 to 17±12 (1 month; p<0.0001) and then to 29±11 (12 months; p=0.013); 63% of patients were meibographic grade 2 before versus 7% after treatment (range, 1-4) (p=0.009); 75% of patients were Oxford grade 1 before versus 41% after treatment (p=0.004) (range, 1-3). No significant difference in the other secondary endpoints was noted. CONCLUSION: Over time, IPL therapy in combination with LLLT appears to improve patients with symptomatic MGD resistant to medical therapy.

In-hospital professional production of patient-specific 3D-printed devices for hand and wrist rehabilitation.

The reported use of 3D printing in hand and wrist rehabilitation has been mostly limited to feasibility studies and case series so far. Some of the reasons are the lack of purpose-built scanning applications, complicated digital design software, and lengthy and error-prone printing processes. We propose a multidisciplinary workflow for in-hospital mass production of patient-specific 3D-printed devices for hand and wrist rehabilitation.

[Thoughts about Light and Sleep]. / Mach nicht zu viel «blau¼.

Thoughts about Light and Sleep Abstract. Many aspects of health and disease are mainly determined by the constant change between light and darkness during a solar day. The resulting physiological rhythms correspond to the circadian rhythm, which was one of the most central drivers in the evolution of humans. However, over the last 20-30 years, these natural rhythms of the change of light and darkness are being increasingly ignored by modern societies. It is well known that these rhythms are modulators of many physiological pathways and any desynchronization or misalignment will activate different pathophysiological pathways, which contribute to the risk of chronic diseases. Light pollution by widespread illumination of our environment and the night sky and uncontrolled man-made use of any light source plays a key role in the pathogenesis of sleep disturbances. Blue light exposure in the evening from any artificial light source (especially from electronic device screens) is of special relevance in this context. In this article a few key facts concerning light, sleep and diseases are presented. We should by all means account for the effects of light and darkness and stop any further light pollution.

Treatment of platelet concentrates and plasma with riboflavin and UV light: Impact in bacterial reduction.

OBJECTIVES: Transfusion of hemocomponents is essential for clinical and surgical procedures and therefore their safety has increased. An option for pathogen reduction includes the combination of riboflavin and UV light. To our knowledge, there are no studies in Latin America that demonstrate the effectiveness of the pathogen reduction in hemocomponents. The objective of this work was to evaluate the efficiency of a pathogens reduction system in platelets concentrates (PC) and plasma. MATERIALS AND METHODS: PC and plasma were contaminated with Escherichia coli, Klebsiella pneumoniae, Streptococcus pyogenes and Staphylococcus epidermidis at 104 to 106 CFU and subjected to bacterial reduction. After bacterial reduction, hemocomponents were subjected to cultivation of surviving bacteria by automated method and classical colonies quantification. Additionally, quality control testing was performed in order to confirm the integrity of platelets and coagulation laboratory values in plasma before and after bacterial reduction. RESULTS: The bacterial death in PC/plasma was expressed by Logarithmic Reduction Value as follows: for both strains (E. coli and S. pyogenes) 4/4, 5/5 and 6/6; for K. pneumoniae 2.54/2.23, 2.94/2.22 and 3.44/2.98, for S. epidermidis 4/4, 3.11/5 and 3.23/4.19, for 104, 105 and 106 CFU, respectively. In PC and plasma, platelet count, pH (at 22°C), activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen, factor VIII and total proteins (TP) were slightly modified. CONCLUSIONS: UV light with riboflavin is able to reduce an important number of pathogens in hemocomponents; however, the bacterial reduction is influenced by the nature and quantity of the pathogen.

Sclerotic scatter.

Sclerotic scatter involves the scattering of incident light by the limbal sclera followed by entry of part of the scattered light into the cornea, where some of the light travels through total internal reflection to the other side, where it scatters a second time in the limbal sclera. It is then visible in the form of a limbal scleral arc of light. Sclerotic scatter has been used for decades to spot and delineate corneal opacities, which disrupt and scatter the light travelling through total internal reflection. To implement the technique, the slit beam and the binoculars of the slit lamp should be dissociated so that the limbal sclera is illuminated, while the binoculars are centered on the cornea. The technique does not provide any information as to the depth of corneal opacities and therefore needs to be complemented by direct illumination. The second sclerotic scatter may also be used clinically, for instance for diode cycloablation, the posterior part of the arc of light projecting 0.5mm behind the scleral spur. This article aims to describe the phenomenon of sclerotic scatter, explaining how the slit-lamp should be set to use this technique, describing its clinical applications (in the opacified cornea and in the normal sclera), showing that the limbal scleral arc of light of sclerotic scatter may be seen under certain circumstances in daily life with the naked eye and, finally, explaining how the arc of light differs from peripheral light focusing ("Coroneo effect").

[The dangers of blue light: True story!]. / Les dangers de la lumière bleue : la vérité !

The dangers of the blue light are the object of numerous publications, for both the scientific community and the general public. The new prolific development of light sources emitting potentially toxic blue light (415-455nm) ranges from LED (Light Emitting Diodes) lamps for interior lighting to television screens, computers, digital tablets and smartphones using OLED (Organic Light Emitting Diode) or AMOLED (Active-Matrix Organic Light Emitting Diode) technology. First we will review some technical terms and the main characteristics of light perceived by the human eye. Then we will discuss scientific proof of the toxicity of blue light to the eye, which may cause cataract or macular degeneration. Analysis of the light spectra of several light sources, from natural light to LED lamps, will allow us to specify even better the dangers related to each light source. LED lamps, whether used as components for interior lighting or screens, are of concern if they are used for extended viewing times and at short distance. While we can protect ourselves from natural blue light by wearing colored glasses which filter out, on both front and back surfaces, the toxic wavelengths, it is more difficult to protect oneself from LED lamps in internal lighting, the use of which should be restricted to "white warmth" lamps (2700K). As far as OLED or AMOLED screens are concerned, the only effective protection consists of using them occasionally and only for a short period of time.