Browsing by Subject "Age"

Now showing 1 - 8 of 8

Open Access
Aging, neurogenesis, and caloric restriction in different model organisms
(International Society on Aging and Disease, 2013) Ergul, A. A.; Ozdemir A.T.; Adams, M. M.
Brain aging is a multifactorial process that is occurring across multiple cognitive domains. A significant complaint that occurs in the elderly is a decrement in learning and memory ability. Both rodents and zebrafish exhibit a similar problem with memory during aging. The neurobiological changes that underlie this cognitive decline are complex and undoubtedly influenced by many factors. Alterations in the birth of new neurons and neuron turnover may contribute to age-related cognitive problems. Caloric restriction is the only non-genetic intervention that reliably increases life span and healthspan across multiple organisms although the molecular mechanisms are not well-understood. Recently the zebrafish has become a popular model organism for understanding the neurobiological consequences but to date very little work has been performed. Similarly, few studies have examined the effects of dietary restriction in zebrafish. Here we review the literature related to memory decline, neurogenesis, and caloric restriction across model organisms and suggest that zebrafish has the potential to be an important animal model for understanding the complex interactions between age, neurobiological changes in the brain, and dietary regimens or their mimetics as interventions.
Open Access
The aid of colour on spatial navigation: A study in a virtual hospital environment
(ACM, 2016) Kumaoğlu, Özge; Olguntürk, Nilgün
The aim of this study is to explore the effects of colour as visuo-spatial cue on spatial navigation and developing a cognitive map in elderly in a simulated virtual hospital environment. The study further purports to explore whether it is possible to improve elders' spatial navigation and cognitive mapping performances as well as younger-aged group, by the aid of coloured visuo-spatial cues. © 2016 ACM.
Open Access
Colour contribution to children's wayfinding in school environments
(Elsevier, 2011) Helvacioglu, E.; Olgunturk, N.
The purpose of this study was to explore the contribution of colour to children's wayfinding ability in school environments and to examine the differences between colours in terms of their remembrance and usability in route learning process. The experiment was conducted with three different sample groups for each of three experiment sets differentiated by their colour arrangement. The participants totalled 100 primary school children aged seven and eight years old. The study was conducted in four phases. In the first phase, the participants were tested for familiarity with the experiment site and also for colour vision deficiencies by using Ishihara's tests for colour-blindness. In the second phase, they were escorted on the experiment route by the tester one by one, from one starting point to one end point and were asked to lead the tester to the end point by the same route. In the third phase, they were asked to describe verbally the route. In the final phase, they were asked to remember the specific colours at their correct locations. It was found that colour has a significant effect on children's wayfinding performances in school environments. However, there were no differences between different colours in terms of their remembrances in route finding tasks. In addition, the correct identifications of specific colours and landmarks were dependent on their specific locations. Contrary to the literature, gender differences were not found to be significant in the accuracy of route learning performances.
Open Access
Data mining experiments on the Angiotensin II-Antagonist in Paroxysmal Atrial Fibrillation (ANTIPAF-AFNET 2) trial: ‘exposing the invisible’
(Oxford University Press, 2016) Okutucu, S.; Katircioglu-Öztürk, D.; Oto, E.; Güvenir, H. A.; Karaagaoglu, E.; Oto, A.; Meinertz, T.; Goette, A.
Aims: The aims of this study include (i) pursuing data-mining experiments on the Angiotensin II-Antagonist in Paroxysmal Atrial Fibrillation (ANTIPAF-AFNET 2) trial dataset containing atrial fibrillation (AF) burden scores of patients with many clinical parameters and (ii) revealing possible correlations between the estimated risk factors of AF and other clinical findings or measurements provided in the dataset. Methods: Ranking Instances by Maximizing the Area under a Receiver Operating Characteristics (ROC) Curve (RIMARC) is used to determine the predictive weights (Pw) of baseline variables on the primary endpoint. Chi-square automatic interaction detector algorithm is performed for comparing the results of RIMARC. The primary endpoint of the ANTIPAF-AFNET 2 trial was the percentage of days with documented episodes of paroxysmal AF or with suspected persistent AF. Results: By means of the RIMARC analysis algorithm, baseline SF-12 mental component score (Pw = 0.3597), age (Pw = 0.2865), blood urea nitrogen (BUN) (Pw = 0.2719), systolic blood pressure (Pw = 0.2240), and creatinine level (Pw = 0.1570) of the patients were found to be predictors of AF burden. Atrial fibrillation burden increases as baseline SF-12 mental component score gets lower; systolic blood pressure, BUN and creatinine levels become higher; and the patient gets older. The AF burden increased significantly at age >76. Conclusions: With the ANTIPAF-AFNET 2 dataset, the present data-mining analyses suggest that a baseline SF-12 mental component score, age, systolic blood pressure, BUN, and creatinine level of the patients are predictors of AF burden. Additional studies are necessary to understand the distinct kidney-specific pathophysiological pathways that contribute to AF burden. Published on behalf of the European Society of Cardiology.
Open Access
Determinants of choosing withdrawal over modern contraceptive methods in Turkey
(Taylor & Francis, 2008) Cindoglu, D.; Sirkeci, I.; Sirkeci, R. F.
Objectives The determinants of the use of withdrawal in Turkey are examined using a multinomial logistic model. Methods Data were drawn from a nation-wide population-based cross-sectional study, the Turkish Demographic Health Surveys that took place in 1998 and 2003. Detailed interviews were conducted with 8576 women aged 15-49 and analysed using SPSS. Results Contextual, cultural and demographic characteristics define women's choice of withdrawal over modern methods. Socio-economic status, education, employment status, and past fertility behaviour are among key determinants. First-ever used contraception method has a very strong impact on later choices. Urban women, the more educated, those with better socioeconomic status, and those living in less crowded households resort less to withdrawal. Experience and empowerment positively linked to modern contraceptive use among women in Turkey. Conclusions The use of contraceptive methods in Turkey differs greatly. Empowerment of women in terms of better socioeconomic status, better education, modern and liberal attitudes towards women and family planning seem to reduce withdrawal use as the main method of contraception. The results suggest the need for education (particularly targeting young women and couples), information and provision of modern contraceptive services particularly for disadvantaged groups.
Open Access
Do Alzheimer’s disease patients appear younger than their real age?
(S. Karger AG, 2020-10) Tüfekçioğlu, Z.; Bilgiç, B.; Zeylan, A. E.; Salah, A. A.; Dibeklioğlu, Hamdi; Emre, M.
Introduction: The most prominent risk factor of Alzheimer’s disease (AD) is aging. Aging also influences the physical appearance. Our clinical experience suggests that patients with AD may appear younger than their actual age. Based on this empirical observation, we set forth to test the hypothesis with human and computer-based estimation systems. Method: We compared 50 early-stage AD patients with 50 age and sex-matched controls. Facial images of all subjects were recorded using a video camera with high resolution, frontal view, and clear lighting. Subjects were recorded during natural conversations while performing Mini-Mental State Examination, including spontaneous smiles in addition to static images. The images were used for age estimation by 2 methods: (1) computer-based age estimation; (2) human-based age estimation. Computer-based system used a state-of-the-art deep convolutional neural network classifier to process the facial images contained in a single-video session and performed frame-based age estimation. Individuals who estimated the age by visual inspection of video sequences were chosen following a pilot selection phase. The mean error (ME) of estimations was the main end point of this study. Results: There was no statistically significant difference between the ME scores for AD patients and healthy controls (p = 0.33); however, the difference was in favor of younger estimation of the AD group. The average ME score for AD patients was lower than that for healthy controls in computer-based estimation system, indicating that AD patients were on average estimated to be younger than their actual age as compared to controls. This difference was statistically significant (p = 0.007). Conclusion: There was a tendency for humans to estimate AD patients younger, and computer-based estimations showed that AD patients were estimated to be younger than their real age as compared to controls. The underlying mechanisms for this observation are unclear.
Restricted
Emeklilik tarihi
(Bilkent University, 2020) Atalay, Ekin; Şentürk, Bekir Alkım; Ercengiz, Murat Ege; Özoral, Ayça; Çivi, Ümit
Türkiye'de faal durumda olan emeklilik kurumlarının temeli Osmanlı İmparatorluğu'na dayanmaktadır. Osmanlı İmparatorluğu'nun son dönemlerinde açılan emekli sandıkları ve çıkarılan Nizamnameler emeklilik açısından ilk çalışmaları oluşturmaktadır. Cumhuriyet döneminde ise Osmanlı'dan kalan kurumlar genişletilmiş ve daha modern kurumlar kurulmuştur. Kurumları birleştirmek için yapılan çalışmalar sonrasında sırasıyla 1950, 1965 ve 1971 yıllarında Emekli Sandığı, Sosyal Sigortalar Kurumu ve Bağ-Kur kurulmuştur.
Open Access
Short-term dietary restriction in old zebrafish changes cell senescence mechanisms
(Elsevier, 2016-10) Arslan-Ergul, Ayca; Erbaba, Begun; Karoglu, Elif Tugce; Halim, Dilara Ozge; Adams, Michelle M.
Brain aging is marked by a decline in cognitive abilities and associated with neurodegenerative disorders. Recent studies have shown, neurogenesis continues into adulthood but is known to be decreasing during advancing age and these changes may contribute to cognitive alterations. Advances, which aim to promote better aging are of paramount importance. Dietary restriction (DR) is the only non-genetic intervention that reliably extends life- and health-span. Mechanisms of how and why DR and age affect neurogenesis are not well-understood, and have not been utilized much in the zebrafish, which has become a popular model to study brain aging and neurodegenerative disease due to widely available genetic tools. In this study we used young (8–8.5 months) and old (26–32.5 months) zebrafish as the model to investigate the effects of a short-term DR on actively proliferating cells. We successfully applied a 10-week DR to young and old fish, which resulted in a significant loss of body weight in both groups with no effect on normal age-related changes in body growth. We found that age decreased cell proliferation and increased senescence associated β-galactosidase, as well as shortened telomere lengths. In contrast, DR shortened telomere lengths only in young animals. Neither age nor DR changed the differentiation patterns of glial cells. Our results suggest that the potential effects of DR could be mediated by telomere regulation and whether these are beneficial or negative remains to be determined.