898 resultados para Age-related maculopathy
Resumo:
Telomerase reverse transcriptase (TERT) is a key component of the telomerase complex. By lengthening telomeres in DNA strands, TERT increases senescent cell lifespan. Mice that lack TERT age much faster and exhibit age-related conditions such as osteoporosis, diabetes and neurodegeneration. Accelerated telomere shortening in both human and animal models has been documented in conditions associated with insulin resistance, including T2DM. We investigated the role of TERT, in regulating cellular glucose utilisation by using the myoblastoma cell line C2C12, as well as primary mouse and human skeletal muscle cells. Inhibition of TERT expression or activity by using siRNA (100. nM) or specific inhibitors (100. nM) reduced basal 2-deoxyglucose uptake by ~. 50%, in all cell types, without altering insulin responsiveness. In contrast, TERT over-expression increased glucose uptake by 3.25-fold. In C2C12 cells TERT protein was mostly localised intracellularly and stimulation of cells with insulin induced translocation to the plasma membrane. Furthermore, co-immunoprecipitation experiments in C2C12 cells showed that TERT was constitutively associated with glucose transporters (GLUTs) 1, 4 and 12 via an insulin insensitive interaction that also did not require intact PI3-K and mTOR pathways. Collectively, these findings identified a novel extra-nuclear function of TERT that regulates an insulin-insensitive pathway involved in glucose uptake in human and mouse skeletal muscle cells. © 2014 Elsevier B.V.
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Lutein and zeaxanthin are carotenoids that are selectively taken up into the macula of the eye, where they are thought to protect against the development of age-related macular degeneration. They are obtained from dietary sources, with the highest concentrations found in dark green leafy vegetables, such as kale and spinach. In this Review, compositional variations due to variety/cultivar, stage of maturity, climate or season, farming practice, storage, and processing effects are highlighted. Only data from studies which report on lutein and zeaxanthin content in foods are reported. The main focus is kale; however, other predominantly xanthophyll containing vegetables such as spinach and broccoli are included. A small amount of data about exotic fruits is also referenced for comparison. The qualitative and quantitative composition of carotenoids in fruits and vegetables is known to vary with multiple factors. In kale, lutein and zeaxanthin levels are affected by pre-harvest effects such as maturity, climate, and farming practice. Further research is needed to determine the post-harvest processing and storage effects of lutein and zeaxanthin in kale; this will enable precise suggestions for increasing retinal levels of these nutrients.
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Ongoing advances in mobile technologies have the potential to improve independence and quality of life of older adults by supporting the delivery of personalised and ubiquitous healthcare solutions. The authors are actively engaged in participatory, user-focused research to create a mobile assistive healthcare-related intervention for persons with age-related macular degeneration (AMD): the authors report here on our participatory research in which participatory design (PD) has been positively adopted and adapted for the design of our mobile assistive technology. The authors discuss their work as a case study in order to outline the practicalities and highlight the benefits of participatory research for the design of technology for (and importantly with) older adults. The authors argue it is largely impossible to achieve informed and effective design and development of healthcare-related technologies without employing participatory approaches, and outline recommendations for engaging in participatory design with older adults (with impairments) based on practical experience.
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Oxidised biomolecules in aged tissue could potentially be used as biomarkers for age-related diseases; however, it is still unclear whether they causatively contribute to ageing or are consequences of the ageing process. To assess the potential of using protein oxidation as markers of ageing, mass spectrometry (MS) was employed for the identification and quantification of oxidative modifications in obese (ob/ob) mice. Lean muscle mass and strength is reduced in obesity, representing a sarcopenic model in which the levels of oxidation can be evaluated for different muscular systems including calcium homeostasis, metabolism and contractility. Several oxidised residues were identified by tandem MS (MS/MS) in both muscle homogenate and isolated sarcoplasmic reticulum (SR), an organelle that regulates intracellular calcium levels in muscle. These modifications include oxidation of methionine, cysteine, tyrosine, and tryptophan in several proteins such as sarcoplasmic reticulum calcium ATPase (SERCA), glycogen phosphorylase, and myosin. Once modifications had been identified, multiple reaction monitoring MS (MRM) was used to quantify the percentage modification of oxidised residues within the samples. Preliminary data suggests proteins in ob/ob mice are more oxidised than the controls. For example SERCA, which constitutes 60-70% of the SR, had approximately a 2-fold increase in cysteine trioxidation of Cys561 in the obese model when compared to the control. Other obese muscle proteins have also shown a similar increase in oxidation for various residues. Further analysis with complex protein mixtures will determine the potential diagnostic use of MRM experiments for analysing protein oxidation in small biological samples such as muscle needle biopsies.
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Gilles de la Tourette syndrome (GTS) and other chronic tic disorders are neurodevelopmental conditions characterized by the presence of tics and associated behavioral problems. Whilst converging evidence indicates that these conditions can affect patients' quality of life (QoL), the extent of this impairment across the lifespan is not well understood. We conducted a systematic literature review of published QoL studies in GTS and other chronic tic disorders to comprehensively assess the effects of these conditions on QoL in different age groups. We found that QoL can be perceived differently by child and adult patients, especially with regard to the reciprocal contributions of tics and behavioral problems to the different domains of QoL. Specifically, QoL profiles in children often reflect the impact of co-morbid attention-deficit and hyperactivity symptoms, which tend to improve with age, whereas adults' perception of QoL seems to be more strongly affected by the presence of depression and anxiety. Management strategies should take into account differences in age-related QoL needs between children and adults with GTS or other chronic tic disorders.
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PURPOSE: To describe changes in intraocular pressure (IOP) in the 'alternative treatments to Inhibit VEGF in Age-related choroidal Neovascularisation (IVAN)' trial (registered as ISRCTN92166560). DESIGN: Randomised controlled clinical trial with factorial design. PARTICIPANTS: Patients (n=610) with treatment naïve neovascular age-related macular degeneration were enrolled and randomly assigned to receive either ranibizumab or bevacizumab and to two regimens, namely monthly (continuous) or as needed (discontinuous) treatment. METHODS: At monthly visits, IOP was measured preinjection in both eyes, and postinjection in the study eye. OUTCOME MEASURES: The effects of 10 prespecified covariates on preinjection IOP, change in IOP (postinjection minus preinjection) and the difference in preinjection IOP between the two eyes were examined. RESULTS: For every month in trial, there was a statistically significant rise in both the preinjection IOP and the change in IOP postinjection during the time in the trial (estimate 0.02 mm Hg, 95% CI 0.01 to 0.03, p<0.001 and 0.03 mm Hg, 95% CI 0.01 to 0.04, p=0.002, respectively). There was also a small but significant increase during the time in trial in the difference in IOP between the two eyes (estimate 0.01 mm Hg, 95% CI 0.005 to 0.02, p<0.001). There were no differences between bevacizumab and ranibizumab for any of the three outcomes (p=0.93, p=0.22 and p=0.87, respectively). CONCLUSIONS: Anti-vascular endothelial growth factor agents induce increases in IOP of small and uncertain clinical significance.
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The development of novel, affordable and efficacious therapeutics will be necessary to ensure the continued progression in the standard of global healthcare. With the potential to address previously unmet patient needs as well as tackling the social and economic effects of chronic and age-related conditions, cell therapies will lead the new generation of healthcare products set to improve health and wealth across the globe. However, if many of the small to medium enterprises (SMEs) engaged in much of the commercialization efforts are to successfully traverse the ‘Valley of Death’ as they progress through clinical trials, there are a number of challenges that must be overcome. No longer do the challenges remain biological but rather a series of engineering and manufacturing issues must also be considered and addressed.
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BACKGROUND: Since 1972, the Australian College of Optometry has worked in partnership with Vision Australia to provide multidisciplinary low-vision care at the Kooyong Low Vision Clinic. In 1999, Wolffsohn and Cochrane reported on the demographic characteristics of patients attending Kooyong. Sixteen years on, the aim of this study is to review the demographics of the Kooyong patient cohort and prescribing patterns. METHODS: Records of all new patients (n = 155) attending the Kooyong Low Vision Clinic for optometry services between April and September 2012 were retrospectively reviewed. RESULTS: Median age was 84.3 years (range 7.7 to 98.1 years) with 59 per cent female. The majority of patients presented with late-onset degenerative pathology, 49 per cent with a primary diagnosis of age-related macular degeneration. Many (47.1 per cent) lived with their families. Mean distance visual acuity was 0.57 ± 0.47 logMAR or approximately 6/24. The median spectacle-corrected near visual acuity was N8 (range N3 to worse than N80). Fifty patients (32.3 per cent) were prescribed new spectacles, 51 (32.9 per cent) low vision aids and five (8.3 per cent) were prescribed electronic magnification devices. Almost two-thirds (63.9 per cent) were referred for occupational therapy management and 12.3 per cent for orientation and mobility services. CONCLUSIONS: The profile of patients presenting for low-vision services at Kooyong is broadly similar to that identified in 1999. Outcomes appear to be similar, aside from an expected increase in electronic devices and technological solutions; however, the nature of services is changing, as treatments for ocular diseases advance and assistive technology develops and becomes more accessible. Alongside the aging population and age-related ocular disease being the predominant cause of low vision in Australia, the health-funding landscape is becoming more restrictive. The challenge for the future will be to provide timely, high-quality care in an economically efficient model.
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Background: Food allergy (FA) is aunique chronic condition as sufferers aregenerally well unless they accidentally ingest an allergen, whereupon symptoms can be life threatening. A good under-standing of the condition is essential forsuccessful self-management, however little is known about children and young teenagers' understanding. This study aimed toexplore understanding of FA in childrenwith and without FA and whether under-standing changes as children get older.Method: Participants aged 6–14 years (53with FA; 89 without), recruited from loc evidence of a prospective associationbetween maternal, perinatal or infant VDIand subsequent IgE-mediated FA schools and allergy clinics took part insemi-structured interviews; data were analysed using thematic analysis.Results: Three themes were identified fromthe data across the different age groups andallergy statuses: food allergy as a sickness, food allergy as an illness and food allergy asintolerance to food. Children aged 6–8 years described FA as a sickness; you were not allowed the food because it makes youpoorly. Children aged 9–11 years also talked about FA as something that makesyou poorly, but many also described it as anillness and understood that symptoms were caused by food. Children aged 12–14 yearsdescribed it as an intolerance or that FA was your body's response to a particularfood. These age-related differences wereseen in children with and without FA. Conclusion: Although sophistication ofknowledge of FA increases with age, it is still a little understood condition by chil-dren and young teenagers. Clear, age-re-lated information about food allergy andhow it should be managed is needed forthose with and without allergy, to avoidmisunderstanding, and aid awareness andbetter self-management of the condition
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Preimplantation genetic diagnosis (PGD) following in vitro fertilization (IVF) offers couples at risk for transmitting genetic disorders the opportunity to identify affected embryos prior to replacement. In particular, embryo gender determination permits screening for X-linked diseases of unknown etiology. Analysis of embryos can be performed by polymerase chain reaction (PCR) amplification of material obtained by micromanipulation. This approach provides an alternative to the termination of an established pregnancy following chorionic villi sampling or amniocentesis. ^ Lately, the focus of preimplantation diagnosis and intervention has been shifting toward an attempt to correct cytoplasmic deficiencies. Accordingly, it is the aim of this investigation to develop methods to permit the examination of single cells or components thereof for clinical evaluation. In an attempt to lay the groundwork for precise therapeutic intervention for age related aneuploidy, transcripts encoding proteins believed to be involved in the proper segregation of chromosomes during human oocyte maturation were examined and quantified. Following fluorescent rapid cycle RT-PCR analysis it was determined that the concentration of cell cycle checkpoint gene transcripts decreases significantly as maternal age increases. Given the well established link between increasing maternal age and the incidence of aneuploidy, these results suggest that the degradation of these messages in aging oocytes may be involved with inappropriate chromosome separation during meiosis. ^ In order to investigate the cause of embryonic rescue observed following clinical cytoplasmic transfer procedures and with the objective of developing a diagnostic tool, mtDNA concentrations in polar bodies and subcellular components were evaluated. First, the typical concentration of mtDNA in human and mouse oocytes was determined by fluorescent rapid cycle PCR. Some disparity was noted between the copy numbers of individual cytoplasmic samples which may limit the use of the current methodology for the clinical assessment of the corresponding oocyte. ^
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The purpose of this study was to investigate the effectiveness of an experimental teaching method, Sport Aerobics, on the basketball skill acquisition of fifth grade students. This study investigated the differences in the shooting, dribbling, and passing scores of students taught with Sport Aerobics instruction compared to those taught with a traditional method, Practice Style. Sport Aerobics is an instructional method based on a theoretical framework developed by the researcher to enhance skill acquisition. This framework leads to teaching strategies such as using immediate feedback and specific cueing; arranging for students to engage in object free movement; arranging lessons, according to the framework's concept of movement progression, into lessons staged according to skill and sub-skill complexity; and instructing based on whole group organization. Sport Aerobic instructional strategies were designed to facilitate process learning that is recognized as important in today's development learning approach for age related curriculums. In contrast, the traditional Practice Style uses product-oriented strategies. ^ Four classrooms, consisting of seventy-nine fifth grade students from two physical education programs, at different locations, were randomly assigned to two treatments; Sport Aerobics and Practice Style for instruction over a 15 period curriculum. Using the American Alliance Physical Education Recreation & Dance tests, both groups were pretested and posttested for skill achievement of shooting, dribbling, and passing. Pretest and posttest skill score samples were collected and evaluated. ANCOVAs were performed on the posttests adjusted for the pretests to determine whether or not there would be greater achievement of skills with the Sport Aerobics method. Results failed to establish significant scoring differences between the two methods. Based on the literature and study findings a recommendation is made that longer lesson units will assist in the investigation of the effectiveness of both the instructional model and the individual elements that facilitate skill acquisition. ^
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Age-related macular degeneration (AMD) is the leading cause of blindness inAmerica. The fact that AMD wreaks most of the damage in the center of the retina raises the question of whether light, integrated over long periods, is more concentrated in the macula. A method, based on eye-tracking, was developed to measure the distribution of light in the retina under natural viewing conditions. The hypothesis was that integrated over time, retinal illumination peaked in the macula. Additionally a possible relationship between age and retinal illumination was investigated. The eye tracker superimposed the subject's gaze position on a video recorded by a scene camera. Five informed subjects were employed in feasibility tests, and 58 naïve subjects participated in 5 phases. In phase 1 the subjects viewed a gray-scale image. In phase 2, they observed a sequence of photographic images. In phase 3 they viewed a video. In phase 4, they worked on a computer; in phase 5, the subjects walked around freely. The informed subjects were instructed to gaze at bright objects in the field of view and then at dark objects. Naïve subjects were allowed to gaze freely for all phases. Using the subject's gaze coordinates, and the video provided by the scene camera, the cumulative light distribution on the retina was calculated for ∼15° around the fovea. As expected for control subjects, cumulative retinal light distributions peaked and dipped in the fovea when they gazed at bright or dark objects respectively. The light distribution maps obtained from the naïve subjects presented a tendency to peak in the macula for phases 1, 2, and 3, a consistent tendency in phase 4 and a variable tendency in phase 5. The feasibility of using an eye-tracker system to measure the distribution of light in the retina was demonstrated, thus helping to understand the role played by light exposure in the etiology of AMD. Results showed that a tendency for light to peak in the macula is a characteristic of some individuals and of certain tasks. In these situations, risk of AMD could be increased. No significant difference was observed based on age.
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Heart valve disease occurs in adults as well as in pediatric population due to age-related changes, rheumatic fever, infection or congenital condition. Current treatment options are limited to mechanical heart valve (MHV) or bio-prosthetic heart valve (BHV) replacements. Lifelong anti-coagulant medication in case of MHV and calcification, durability in case of BHV are major setbacks for both treatments. Lack of somatic growth of these implants require multiple surgical interventions in case of pediatric patients. Advent of stem cell research and regenerative therapy propose an alternative and potential tissue engineered heart valves (TEHV) treatment approach to treat this life threatening condition. TEHV has the potential to promote tissue growth by replacing and regenerating a functional native valve. Hemodynamics play a crucial role in heart valve tissue formation and sustained performance. The focus of this study was to understand the role of physiological shear stress and flexure effects on de novo HV tissue formation as well as resulting gene and protein expression. A bioreactor system was used to generate physiological shear stress and cyclic flexure. Human bone marrow mesenchymal stem cell derived tissue constructs were exposed to native valve-like physiological condition. Responses of these tissue constructs to the valve-relevant stress states along with gene and protein expression were investigated after 22 days of tissue culture. We conclude that the combination of steady flow and cyclic flexure helps support engineered tissue formation by the co-existence of both OSS and appreciable shear stress magnitudes, and potentially augment valvular gene and protein expression when both parameters are in the physiological range.