Does air gas aesthesiometry generate a true mechanical stimulus for corneal sensitivity measurement?

Background: Belmonte Ocular Pain Meter (OPM) air jet aesthesiometry overcomes some of the limitations of the Cochet-Bonnet aesthesiometer. However, for true mechanical corneal sensitivity measurement, the airflow stimulus temperature of the aesthesiometer must equal ocular surface temperature (OST), to avoid additional response from temperature-sensitive nerves. The aim of this study was to determine: (A) the stimulus temperature inducing no or least change in OST; and (B) to evaluate if OST remains unchanged with different stimulus durations and airflow rates. Methods: A total of 14 subjects (mean age 25.14 2.18 years; seven women) participated in this clinical cohort study: (A) OST was recorded using an infrared camera (FLIR A310) during the presentation of airflow stimuli, at five temperatures, ambient temperature (AT) +5C, +10C, +15C, +20C and +30C, using the OPM aesthesiometer (duration three seconds; over a four millimetre distance; airflow rate 60 ml/min); and (B) OST measurements were repeated with two stimulus temperatures (AT +10C and +15C) while varying stimulus durations (three seconds and five seconds) and airflow rates (30, 60, 80 and 100 ml/min). Inclusion criteria were age <40 years, no contact lens wear, absence of ocular disease including dry eye, and no use of artificial tears. Repeated measures (analysis of variance) and appropriate post-hoc t-tests were applied. Results: (A) Stimulus temperatures of AT +10C and +15C induced the least changes in OST (−0.20 0.13C and 0.08 0.05C). (B) OST changes were statistically significant with both stimulus temperatures and increased with increasing airflow rates (p < 0.001), and were more marked with stimulus temperature AT +10C. Conclusion: A true mechanical threshold for corneal sensitivity cannot be established with the air stimulus of the Belmonte OPM because its air jet stimulus with mechanical setting is likely to have a thermal component. Appropriate stimulus selection for an air jet aesthesiometer must incorporate stimulus temperature control that can vary with stimulus duration and airflow rate

Early predictors of separation anxiety disorder : early stranger anxiety, parental pathology and prenatal factors

&lt;i&gt;Objective:&lt;/i&gt; The present study seeks to extend research on the etiology of separation anxiety disorder (SAD) in a German-speaking sample by examining differences between children with SAD and healthy comparisons, using a retrospective-reporting paradigm. &lt;i&gt;Method:&lt;/i&gt; The sample included 106 children with SAD and 44 healthy children between the ages of 4 and 14 years. Parents completed questionnaires and structured clinical interviews to assess parental pathology, pregnancy variables and strong early stranger anxiety. &lt;i&gt;Results:&lt;/i&gt; Children with SAD were more likely than healthy children to have had a phase of stronger stranger anxiety in infancy. Further, early stranger anxiety remained a significant predictor of SAD after controlling for maternal depression. Meaningful effects were not found for the influence of parental age at birth or other pregnancy factors. &lt;i&gt;Conclusion:&lt;/i&gt; This study provides beginning evidence of the potential predictive value of strong stranger anxiety in distinguishing children with SAD from those with no disorder, above and beyond the influence of parental pathology.</jats:p

Emerging dietary patterns: impact on child health

What we eat today and how we decide to produce sufficient food to meet both demand and nutritional requirements will determine the availability, diversity and quality of diets for future generations. Acceptability and normalisation of new dietary patterns must be prioritised to the same extent as education on environmental sustainability and health, because these are important social levers. They can help to reduce the psychosocial barriers and anxieties often connected to the behaviour changes that are needed to transition away from the traditional Western eating habits that are now increasingly subject to critical scrutiny. Without understanding the motivations and facilitators to change eating habits (and then designing and amplifying solutions which make those changes attractive and compelling in the modern world) positive changes to young people’s health and their environment through better food will not come quickly enough to halt potentially catastrophic consequences for people and planet. Changing consumption is seen by experts as the most powerful lever compared to food waste reduction or more efficient food production methods and technological solutions. There is simply not enough on Earth to sustain the increase of intensification required to continue feeding a global population on its current trajectory with a diet so rich in animal produce. However, radical behaviour modification is challenging and therefore cross-sector, bold and perhaps unorthodox leadership is necessary to inspire alteration in the food system, which will have a knock-on effect in terms of changing food environments and therefore food perceptions, narratives and behaviours. There are no ‘quick fix’ solutions, but what is undeniable is that populations can only make effective shifts in dietary patterns if government and the food industry help them to make those changes. This requires budgetary investment in public health information and the implementation of policies that promote ways to eat healthily that are also affordable and environmentally sustainable. The aim is to offer food that tastes as good as it can be made to look so that uptake is maximised and the benefits are cumulative. The inevitable upheaval incurred by making any alteration to entrenched patterns of consumption that have been centuries in the making should not be underestimated, but carrying on as before is no longer credible nor desirable. The aim is to offer ‘nutritious’ food. ‘If we don’t take action, the collapse of our civilisations and the extinction of much of the natural world is on the horizon’ Sir David Attenborough. This Report is our initial contribution to a conversation that has only just begun.It is unlikely to be the last

Differential regulation of key stages in early corneal wound healing by TGF-beta isoforms and their inhibitors

PURPOSE: Inhibition of TGF-beta reduces myofibroblast differentiation and fibrosis in the cornea. Determining the actions of distinct TGF-beta isoforms and their inhibitors during early corneal wound healing is an essential step in guiding therapeutic intervention. METHODS: Bovine serum-free corneal cell and wounded organ cultures were challenged with a range of concentrations of TGF-beta1, -beta2, and -beta3; IL-10; and neutralizing human monoclonal antibodies (mAbs) against TGF-beta1 (CAT-192) or -beta2, (CAT-152). Cultures were assessed for re-epithelialization, proliferation (cell counts and cresyl violet assay), morphology (histologic examination), repopulation of the area under the wound, and myofibroblast transformation (alpha-smooth muscle actin) between 0 and 5 days. RESULTS: TGF-beta1 delayed re-epithelialization, increased repopulation of the stroma, increased keratocyte proliferation and was the only isoform to promote myofibroblast differentiation. The anti-TGF-beta1 mAb, CAT-192 promoted re-epithelialization and reduced repopulation of the stroma. Exogenous TGF-beta3 had little effect on re-epithelialization but reduced repopulation of the stroma. IL-10 promoted corneal re-epithelialization at low doses but inhibited this response at high doses. Stromal repopulation was prevented by all doses of IL-10. TGF-beta2 or the anti-TGF-beta2 mAb, CAT-152 had little effect on any repair parameter. CONCLUSIONS: The results confirm TGF-beta1 as the principal isoform in corneal wound healing and suggest that inhibition of the action of TGF-beta1 can promote corneal wound healing. Treatment with the anti-TGF-beta1 mAb CAT-192 accelerates corneal re-epithelialization but reduces cell repopulation of the stroma. The cytokines TGF-beta3 and IL-10 have opposing actions to that of TGF-beta1

Measuring the refractive index of bovine corneal stromal cells using quantitative phase imaging

The cornea is the primary refractive lens in the eye and transmits >90% of incident visible light. It has been suggested that the development of postoperative corneal haze could be due to an increase in light scattering from activated corneal stromal cells. Quiescent keratocytes are thought to produce crystallins that match the refractive index of their cytoplasm to the surrounding extracellular material, reducing the amount of light scattering. To test this, we measured the refractive index (RI) of bovine corneal stromal cells, using quantitative phase imaging of live cells in vitro, together with confocal microscopy. The RI of quiescent keratocytes (RI = 1.381 ± 0.004) matched the surrounding matrix, thus supporting the hypothesis that keratocyte cytoplasm does not scatter light in the normal cornea. We also observed that the RI drops after keratocyte activation (RI = 1.365 ± 0.003), leading to a mismatch with the surrounding intercellular matrix. Theoretical scattering models showed that this mismatch would reduce light transmission in the cornea. We conclude that corneal transparency depends on the matching of refractive indices between quiescent keratocytes and the surrounding tissue, and that after surgery or wounding, the resulting RI mismatch between the activated cells and their surrounds significantly contributes to light scattering

Healthy families: the present and future role of the supermarket

In this report, we contend that the grocery industry must be accountable for their role in an obesogenic environment. The social context most likely to support making healthy behaviour changes is the family. For families, supermarkets represent more than merely places in which to spend their money. They establish the values that underpin the ways in which people conduct their lives

Investigating hyper-vigilance for social threat of lonely children

The hypothesis that lonely children show hypervigilance for social threat was examined in a series of three studies that employed different methods including advanced eye-tracking technology. Hypervigilance for social threat was operationalized as hostility to ambiguously motivated social exclusion in a variation of the hostile attribution paradigm (Study 1), scores on the Children’s Rejection-Sensitivity Questionnaire (Study 2), and visual attention to socially rejecting stimuli (Study 3). The participants were 185 children (11 years-7 months to 12 years-6 months), 248 children (9 years-4 months to 11 years-8 months) and 140 children (8 years-10 months to 12 years-10 months) in the three studies, respectively. Regression analyses showed that, with depressive symptoms covaried, there were quadratic relations between loneliness and these different measures of hypervigilance to social threat. As hypothesized, only children in the upper range of loneliness demonstrated elevated hostility to ambiguously motivated social exclusion, higher scores on the rejection sensitivity questionnaire, and disengagement difficulties when viewing socially rejecting stimuli. We found that very lonely children are hypersensitive to social threat