Visual function and dysfunction in early and late age-related maculopathy

Late age-related maculopathy (ARM) is responsible for the majority of blind registrations in the Western world among persons over 50 years of age. It has devastating effects on quality of life and independence and is becoming a major public health concern. Current treatment options are limited and most aim to slow progression rather than restore vision; therefore, early detection to identify those patients most suitable for these interventions is essential. In this work, we review the literature encompassing the investigation of visual function in ARM in order to highlight those visual function parameters which are affected very early in the disease process. We pay particular attention to measures of acuity, contrast sensitivity (CS), cone function, electrophysiology, visual adaptation, central visual field sensitivity and metamorphopsia. We also consider the impact of bilateral late ARM on visual function as well as the relationship between measures of vision function and self-reported visual functioning. Much interest has centred on the identification of functional changes which may predict progression to neovascular disease; therefore, we outline the longitudinal studies, which to date have reported dark-adaptation time, short-wavelength cone sensitivity, colour-match area effect, dark-adapted foveal sensitivity, foveal flicker sensitivity, slow recovery from glare and slower foveal electroretinogram implicit time as functional risk factors for the development of neovascular disease. Despite progress in this area, we emphasise the need for longitudinal studies designed in light of developments in disease classification and retinal imaging, which would ensure the correct classification of cases and controls, and provide increased understanding of the natural course and progression of the disease and further elucidate the structure-function relationships in this devastating disorder.

Considerations for using sucrose to reduce procedural pain in preterm infants

Preterm and critically ill newborns admitted to a NICU undergo repeated skin-breaking procedures that are necessary for their survival. Sucrose is rapidly becoming the accepted clinical standard nonpharmacologic intervention for managing acute procedural pain for these infants. Although shown to be safe in single doses, only 4 studies have evaluated the effects of repeated doses of sucrose over relatively short periods of time. None has examined the use of sucrose throughout the NICU stay, and only 1 study evaluated the neurodevelopmental outcomes after repeated doses of sucrose. In that study, infants born at 10 doses per day in the first week of life were more likely to show poorer attention and motor development in the early months after discharge from the NICU. Results of studies in animal models have suggested that the mechanism of action of sucrose is through opioid pathways; however, in human infants, little has been done to examine the physiologic mechanisms involved, and the findings reported thus far have been ambiguous. Drawing from the growing animal literature of research that has examined the effects of chronic sugar exposure, we describe alternative amine and hormone pathways that are common to the processing of sucrose, attention, and motor development. In addition, a review of the latest research to examine the effects of repeated sucrose on pain processing is presented. These 2 literatures each can inform the other and can provide an impetus to initiate research to examine not only the mechanisms involved in the calming mechanisms of sucrose but also in the long-term neurodevelopmental effects of repeated sucrose in those infants born extremely preterm or critically ill.

Farm animal welfare:Assessing risks attributable to the prenatal environment

An ever-expanding scientific literature highlights the impact of the prenatal environment on many areas of biology. Across all major farmed species, experimental studies have clearly shown that prenatal experiences can have a substantial impact on outcomes relevant to later health, welfare and productivity. In particular, stress or sub-optimal nutrition experienced by the mother during pregnancy has been shown to have wide-ranging and important effects on how her offspring cope with their social, physical and infectious environment. Variation in the conditions for development provided by the reproductive tract or egg, for instance by altered nutritional supply or hormonal exposure, may therefore explain a large degree of variation in many welfare- and productivity-relevant traits. The scientific literature suggests a number of management practices for pre-birth/hatch individuals that could compromise their later welfare. Such studies may have relevance for the welfare of animals under human care, depending on the extent to which real life conditions involve exposure to these practices. Overall, the findings highlight the importance of extending the focus on animal welfare to include the prenatal period, an aspect which until recently has been largely neglected. © 2012 Universities Federation for Animal Welfare The Old School.