236 research outputs found

    Investigative Ophthalmology & Visual Science Articles Quantitative Magnetic Resonance Imaging in Assessment of the Blood-Retinal Barrier

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    Application of magnetic resonance imaging (MRI) in two- The initial lesions of diabetic retinopathy include retinal capillary pericyte loss, endothelial cell proliferation, and microaneurysm formation. 1 These changes are accompanied by capillary dilatation and increased capillary permeability due to disruption of the inner blood-retinal barrier. While qualitative increases in permeability are demonstrated readily by fluorescein angiography, quantifying fluorescein leakage by vitreous fluorophotometry continues to be subject to several practical problems. These include the age-related reduction in light transmission by the lens, the necessity for clear optic media, 2 " 4 an intact vitreous gel 5 and the restriction with current fluoro

    Tumor Necrosis Factor-α in Diabetic Plasma Increases the Activity of Core 2 GlcNAc-T and Adherence of Human Leukocytes to Retinal Endothelial Cells

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    A large body of evidence now implicates increased leukocyte-endothelial cell adhesion as a key early event in the development of diabetic retinopathy. We recently reported that raised activity of the glycosylating enzyme core 2 β 1,6-N-acetylglucosaminyltransferase (GlcNAc-T) through protein kinase C (PKC)β2-dependent phosphorylation plays a fundamental role in increased leukocyte-endothelial cell adhesion and capillary occlusion in retinopathy. In the present study, we demonstrate that following exposure to plasma from diabetic patients, the human promonocytic cell line U937 exhibits a significant elevation in core 2 GlcNAc-T activity and increased adherence to cultured retinal capillary endothelial cells. These effects of diabetic plasma on enzyme activity and cell adhesion, mediated by PKCβ2-dependent phosphorylation of the core 2 GlcNAc-T protein, were found to be triggered by increased plasma levels of tumor necrosis factor (TNF)-α. Levels of enzyme activity in plasma-treated U937 cells were closely dependent on the severity of diabetic retinopathy, with the highest values observed upon treatment with plasma of patients affected by proliferative retinopathy. Furthermore, we noted much higher correlation, as compared with control subjects, between increased values of core 2 GlcNAc-T activity and cell adhesion properties. Based on the prominent role of TNF-α in the development of diabetic retinopathy, these observations further validate the significance of core 2 GlcNAc-T in the pathogenesis of capillary occlusion, thereby enhancing the therapeutic potential of specific enzyme inhibitors

    The role of healthcare professionals in encouraging parents to see and hold their stillborn baby: a meta-synthesis of qualitative studies.

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    Background: Globally, during 2013 there were three million recorded stillbirths. Where clinical guidelines exist some recommend that professionals do not encourage parental contact. The guidance is based on quantitative evidence that seeing and holding the baby is not beneficial for everyone, but has been challenged by bereaved parents' organisations. We aim to inform future guideline development through a synthesis of qualitative studies reporting data relevant to the research question; how does the approach of healthcare professionals to seeing and holding the baby following stillbirth impact parents views and experiences? Methods/Findings: Using a predetermined search strategy of PubMed and PsychINFO we identified robust qualitative studies reporting bereaved parental views and/or experiences relating to seeing and holding their stillborn baby (final search 24 February, 2014). Eligible studies were English language, reporting parental views, with gestational loss >20weeks. Quality was independently assessed by three authors using a validated tool. We used meta-ethnographic techniques to identify key themes and a line of argument synthesis. We included 12 papers, representing the views of 333 parents (156 mothers, 150 fathers, and 27 couples) from six countries. The final themes were: "[Still]birth: Nature of care is paramount", "Real babies: Perfect beauties, monsters and spectres", and "Opportunity of a lifetime lost." Our line-of-argument synthesis highlights the contrast between all parents need to know their baby, with the time around birth being the only time memories can be made, and the variable ability that parents have to articulate their preferences at that time. Thus, we hypothesised that how health professionals approach contact between parents and their stillborn baby demands a degree of active management. An important limitation of this paper is all included studies originated from high income, westernised countries raising questions about the findings transferability to other cultural contexts. We do not offer new evidence to answer the question "Should parents see and hold their stillborn baby?", instead our findings advance understanding of how professionals can support parents to make appropriate decisions in a novel, highly charged and dynamic situation. Conclusions: Guidelines could be more specific in their recommendations regarding parental contact. The role of healthcare professionals in encouraging parents to see and hold their stillborn baby is paramount. Parental choice not to see their baby, apprehension, or uncertainty should be continuously revisited in the hours after birth as the opportunity for contact is fleeting and final

    Spatial distribution of early red lesions is a risk factor for development of vision-threatening diabetic retinopathy

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    Aims/hypothesis Diabetic retinopathy is characterised by morphological lesions related to disturbances in retinal blood flow. It has previously been shown that the early development of retinal lesions temporal to the fovea may predict the development of treatment-requiring diabetic maculopathy. The aim of this study was to map accurately the area where lesions could predict progression to vision-threatening retinopathy. Methods The predictive value of the location of the earliest red lesions representing haemorrhages and/or microaneurysms was studied by comparing their occurrence in a group of individuals later developing vision-threatening diabetic retinopathy with that in a group matched with respect to diabetes type, age, sex and age of onset of diabetes mellitus who did not develop vision-threatening diabetic retinopathy during a similar observation period. Results The probability of progression to vision-threatening diabetic retinopathy was higher in a circular area temporal to the fovea, and the occurrence of the first lesions in this area was predictive of the development of vision-threatening diabetic retinopathy. The calculated peak value showed that the risk of progression was 39.5% higher than the average. There was no significant difference in the early distribution of lesions in participants later developing diabetic maculopathy or proliferative diabetic retinopathy. Conclusions/interpretation The location of early red lesions in diabetic retinopathy is predictive of whether or not individuals will later develop vision-threatening diabetic retinopathy. This evidence should be incorporated into risk models used to recommend control intervals in screening programmes for diabetic retinopathy

    Prevalence of diabetic retinopathy in Tehran province: a population-based study

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    <p>Abstract</p> <p>Background</p> <p>To determine the prevalence and characteristics of diabetic retinopathy (DR) among Iranian patients with diabetes.</p> <p>Methods</p> <p>Design: population-based cross-sectional study.</p> <p>Participants: patients with diabetes aged 25 to 64 years in Tehran province, Iran. This survey was conducted from April to October 2007. The study sample was derived from the first national survey of risk factors for non-communicable disease. Diabetes mellitus was defined as a fasting plasma glucose of ≥ 7.0 mmol/l (126 mg/dl) or more, use of diabetic medications, or a physician's diagnosis of diabetes. All patients known to have diabetes underwent an eye examination by bio-microscope and indirect ophthalmoscope to check for any signs of DR through dilated pupils by + 78 lens. Participants were also interviewed and examined to determine their demographic characteristics, medical conditions and the regularity of their eye visits.</p> <p>Results</p> <p>Among 7989 screened patients, 759 (9.5%) had diabetes. Of them, 639 patients (84.2%) underwent eye examination. Five patients (0.7%) with media opacity were excluded. Of 634 examined patients with diabetes, 240 had some degree of diabetic retinopathy, and the overall standardized prevalence of any retinopathy was 37.0% (95% CI: 33.2-40.8), including 27.3% (95% CI: 23.7-30.8) (n = 175) with non-proliferative and 9.6% (95% CI: 7.3-11.9) (n = 65) with proliferative diabetic retinopathy. Clinically significant macular edema and vision-threatening retinopathy were detected in 5.8% (95% CI: 4.0-7.7) (n = 38) and 14.0% (95% CI: 11.3-16.7) (n = 95) of patients, respectively. Only 143 patients (22.6%) with diabetes had a history of regular eye examination.</p> <p>Conclusion</p> <p>This study demonstrated a high prevalence and poor control of DR in Tehran province. This suggests the need for adequate prevention and treatment in patients with diabetes.</p

    Improving eye care for veterans with diabetes: An example of using the QUERI steps to move from evidence to implementation: QUERI Series

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    <p>Abstract</p> <p>Background</p> <p>Despite being a critical part of improving healthcare quality, little is known about how best to move important research findings into clinical practice. To address this issue, the Department of Veterans Affairs (VA) developed the Quality Enhancement Research Initiative (QUERI), which provides a framework, a supportive structure, and resources to promote the more rapid implementation of evidence into practice.</p> <p>Methods</p> <p>This paper uses a practical example to demonstrate the use of the six-step QUERI process, which was developed as part of QUERI and provides a systematic approach for moving along the research to practice pipeline. Specifically, we describe a series of projects using the six-step framework to illustrate how this process guided work by the Diabetes Mellitus QUERI (DM-QUERI) Center to assess and improve eye care for veterans with diabetes.</p> <p>Results</p> <p>Within a relatively short time, DM-QUERI identified a high-priority issue, developed evidence to support a change in the diabetes eye screening performance measure, and identified a gap in quality of care. A prototype scheduling system to address gaps in screening and follow-up also was tested as part of an implementation project. We did not succeed in developing a fully functional pro-active scheduling system. This work did, however, provide important information to help us further understand patients' risk status, gaps in follow-up at participating eye clinics, specific considerations for additional implementation work in the area of proactive scheduling, and contributed to a change in the prevailing diabetes eye care performance measure.</p> <p>Conclusion</p> <p>Work by DM-QUERI to promote changes in the delivery of eye care services for veterans with diabetes demonstrates the value of the QUERI process in facilitating the more rapid implementation of evidence into practice. However, our experience with using the QUERI process also highlights certain challenges, including those related to the hybrid nature of the research-operations partnership as a mechanism for promoting rapid, system-wide implementation of important research findings. In addition, this paper suggests a number of important considerations for future implementation work, both in the area of pro-active scheduling interventions, as well as for implementation science in general.</p
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