Relationship between corneal temperature and i0ntraocular pressure in healthy Individuals. a clinical thermographic analysis

To study the geographical distribution of corneal temperature (CT) and its influence on the intraocular pressure (IOP) of healthy human volunteers. Materials and Methods. Fifteen subjects (7 M, 8 F), 33.8 +/- 17.4 years old, were enrolled in this pilot, cross-sectional study. Measurements of CT were taken after one hour with closed eyelids (CET) or closed eyelids with a cooling mask (cm-CET) and compared to baseline. Results. If compared to baseline, after CET, average CT significantly increased by 0.56 degrees C in the RE and by 0.48 degrees C in the LE (p < 0.001) and IOP concomitantly significantly increased by 1.13 mm Hg and 1.46 mm Hg, respectively, in each eye (p < 0.001). After cm-CET, average CT significantly decreased by 0.11 degrees C and 0.20 degrees C, respectively, in the RE and LE (RE p = 0.04; LE p = 0.024), followed by a significant IOP decrease of 2.19 mm Hg and 1.54 mm Hg, respectively, in each eye (RE p < 0.001; LE = 0.0019). Conclusion. Significant variations of CT occurred after CET and cm-CET and were directly correlated with significant differences of IOP. It can be speculated that both oxidative stress and sympathetic nerve fiber stimulation by temperature oscillations may affect the regulation of AH vortex flow and turnover, thus influencing IOP values

Neovascularization in alkali-burned rabbit cornea

Objective: To study the neovascularization in regenerating and proliferating corneal cells following a standard alkali injury in rabbit eye. Methods: Three and six weeks after the creation of an alkali burn in the center of the right cornea of six albino rabbits, the animals were killed and histological sections from the cornea of both eyes were stained, photographed and studied for a possible formation of a neovascularization. The photographs were examined using the Quantimet image analyzer (Leica) and statistical analysis of the data was performed. Results: Sections of the injured cornea showed the formation of neovessels in the epithelial and superficial stromal layers. The neovascularization is present after 3 weeks of the corneal injury. After 6 weeks from the corneal alkali burn, neovessels are increased. Conclusions: There is a growing body of evidence suggesting that vascular abnormalities may play a crucial rolein several ocular diseases. To improve our knowledge of the vascular involvement in these conditions, there is a need for a non-invasive imaging modality capable of assessing microcirculation within ocular tissue beds both in vitro and in vivo. This study shows that ultra-high sensitive optical microangiography, associated with other experimental techniques, is an adequate technique to visualize the eye surface microcirculations and to quantify microvascular vessel density under both normal and physio-pathological conditions

Cataract surgery complications: An in vitro model of toxic effects of Ropivacaine and lidocaine

Background: Intraoperative lidocaine is widely used in controlling discomfort during cataract surgery. However, recent studies have confirmed the toxic effect of lidocaine on ganglion cells. Ropivacaine is an anesthetic recently introduced in clinical practice that couples a long anesthetic effect with a mild vasoconstrictive action. Objective: The aim of this study was an in vitro evaluation of the efficacy of ropivacaine in reducing the degenerative effects usually observed during lidocaine treatment. Methods: Ropivacaine and lidocaine toxicity has been evaluated in murine fibroblasts 3T6 by measuring percentage of cell death, cell growth inhibition, and DNA degradation. The choice of this cellular line is motivated by the presence of a complete apoptotic system that can be assimilated to the endothelium precursor cells. Results: We observed that lidocaine 0.25% decreases cell viability and causes DNA degradation in murine fibroblasts 3T6, whereas ropivacaine 0.5% does not cause any cellular or molecular degenerative effect. Conclusions: Our in vitro studies confirm that ropivacaine is less toxic than lidocaine to these cells. Therefore, in vivo studies in the anterior chamber could be useful to evaluate the effects of ropivacaine versus lidocaine in intracameral anesthesia in cataract surgery. © 2011 Vergani & Rusconi, publisher and licensee Adis Data Information BV

Biomolecular Modulation of Neurodegenerative Events during Ageing

The objective is to assess the modulation of retinal and optic nerve degenerative events induced by the combination of α-lipoic acid (ALA) and superoxide dismutase (SOD) in an animal model of ageing. For this study, 24 male Wistar-Harlan strain rats were left to age for up to 24 months. One group of rats was subjected to a diet supplemented with ALA and SOD for 8 weeks, while another group was used as a positive control and not subjected to any dietary treatment. To assess the cytoprotective effects of the antioxidants, a morphological analysis was carried out on sections of retina and optic nerve head, stained with haematoxylin-eosin, followed by an analysis of the modifications to nuclear DNA detected by the TUNEL technique. The lipid peroxidation assay was used to assess the damage induced by oxidative stress at cell membrane level. The molecules involved in apoptosis mediated by oxidative stress, such as caspase-3 and inducible nitric oxide synthase, were also assayed by immunolocalization and western blot. ALA and SOD are able to counteract senile neurodegenerative deterioration to the retina and optic nerve. Indeed, the combination of these antioxidant molecules can reduce oxidative stress levels and thus prevent both nuclear degradation and subsequent cell death

Hypotensive Effect of Nanomicellar Formulation of Melatonin and Agomelatine in a Rat Model: Significance for Glaucoma Therapy

Background: Melatoninergic agents are known to reduce intraocular pressure (IOP). The present study was performed to evaluate the effect of nanomicellar formulations of melatoninergic agents on IOP in the rat. Methods: Tonometry was used to measure IOP in eyes instilled with melatonin or agomelatine. Ocular hypertension was induced by the injection of methylcellulose in the anterior chamber. Results: Melatonin formulated in nanomicelles had a longer lasting hypotonizing effect on IOP with respect to melatonin in saline. Nanomicellar formulations of melatonin and agomelatine, either alone or in combination, had lowering effects that did not depend on their concentration or their combination, which, however, resulted in an increased duration of the hypotonizing effect. The duration of the lowering effect was further increased by the addition of lipoic acid. Conclusions: We demonstrated the effective hypotonizing activity of melatonin and agomelatine in combination with lipoic acid. Although results in animals cannot be directly translated to humans, the possibility of developing novel therapeutical approaches for patients suffering from hypertensive glaucoma should be considered

Analysis of Photo Sharing and Visual Social Relationships. Instagram as Case Study

This article discusses how visuality, through the mobility of Instagram, modifies individuals’ mediated lives. In particular, it examines how Instagram transforms individuals’ perceptions of their interpersonal relationships. It advances a critical re-reading of the concept of mobility (smart mobile devices) and the new approach to sociality. Conducting an empirical examination, this article delineates the changing dynamics that digitality determines within contemporary life experiences. Findings show that the ubiquitous use of smart mobile devices leads individuals towards the development of new forms and conceptions of mobile mediated visualities. In order to understand the rise of new visual practices based on Pink’s (2007) ethnographic work, this article considers how relationships develop among individuals, visual technologies, practices and images, society and culture. A qualitative approach informed by netnography (Kozinets, 2010), computer-mediated interviews and visual analysis (Rose, 2007) is employed in this study. The critical analysis of 44 participant interviews and their photo sharing behaviour presents the transformations that the mediation and mobility of Instagram bring into everyday relations between humans and technologies. The increased use of social media shows how sociality is affected and mediated by new mobile technologies. Although the social potentiality of (visual) social relationships itself does not offer a variety of verbal communication mechanisms, it encourages offline meetings or the relocation onto other social media. This shows that every alteration in the structure of societies has influence on individuals and on their means of expression

Synthetic Social Support: Theorizing Lay Health Worker Interventions

Levels of social support are strongly associated with health outcomes and inequalities. The use of lay health workers (LHWs) has been suggested by policy makers across the world as an intervention to identify risks to health and to promote health, particularly in disadvantaged communities. However, there have been few attempts to theorize the work undertaken by LHWs to understand how interventions work. In this article, the authors present the concept of 'synthetic socialsupport' and distinguish it from the work of health professionals or the spontaneous social support received from friends and family. The authors provide new empirical data to illustrate the concept based on qualitative, observational research, using a novel shadowing method involving clinical and non-clinical researchers, on the everyday work of 'pregnancy outreach workers' (POWs) in Birmingham, UK. The service was being evaluated as part of a randomized controlled trial. These LHWs provided instrumental, informational, emotional and appraisal support to the women they worked with, which are all key components of social support. The social support was 'synthetic' because it was distinct from the support embedded in spontaneous social networks: it was non-reciprocal; it was offered on a strictly time-limited basis; the LHWs were accountable for the relationship, and the social networks produced were targeted rather than spontaneous. The latter two qualities of this synthetic form of social support may have benefits over spontaneous networks by improving the opportunities for the cultivation of new relationships (both strong and weak ties) outside the women's existing spontaneous networks that can have a positive impact on them and by offering a reliable source of health information and support in a chaotic environment. The concept of SSS can help inform policy makers about how deploying lay workers may enable them to achieve desired outcomes, specify their programme theories and evaluate accordingly. [Abstract copyright: Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.