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Age Related Changes (age + relate_change)
Selected AbstractsCortical lens opacification in IcelandACTA OPHTHALMOLOGICA, Issue 2 2001Reykjavik Eye Study, Risk Factor Analysis ABSTRACT. Purpose: Cortical lens opacification has been associated with outdoor exposure and UV radiation more than other types of lens opacification. We studied risk factors for cortical lens opacification only, the most common as well as the earliest age related change we observe in the lens. Methods: 1,045 persons, 583 females and 462 males, 50 years and older, underwent a detailed eye examination and answered a questionnaire. Participants with cortical lens opacification grade I, totalling 374 persons, were assigned to case-control study I, and to case-control study II those with cortical lens opacification grades II and III, totalling 82 subjects. 378 age and sex matched persons served as controls. Results: Those who spent more than 4 hours/day outside on weekdays, in their 20's,30's and 40's,50's respectively, were found to have increased risk of moderate to severe cortical lens opacification. Thus the relative risk for grades II & III, was 2.80 (95% CI 1.01,7.80) and 2.91 (95% CI 1.13,9.62) respectively. Ageing and systemic cortical steroids use were also found to be risk factors. Conclusion: Outdoor exposure appears to be associated with increased risk of moderate to severe cortical lens opacification. Ageing is, however, the main risk factor. [source] Play fighting in androgen-insensitive tfm rats: Evidence that androgen receptors are necessary for the development of adult playful attack and defenseDEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2006Evelyn F. Field Abstract The frequency of playful attack and the style of playful defense, are modifiable by gonadal steroids and change after puberty in male and female rats. The present study examined the play behavior exhibited by testicular feminized mutation (tfm) -affected males, who are insensitive to androgens but can bind estrogens aromatized from androgens, to determine the relative contributions of androgens and estrogens to the age-related changes in play behavior. tfm males did not exhibit a decrease in playful attack with age and were more likely to maintain the use of complete rotations, a juvenile form of playful defense, into adulthood. tfm males did however, show age related changes in the use of partial rotations and upright postures, two other forms of playful defense, that were similar to normal males. These data suggest that the development of play fighting and defense in males is dependent on both androgen- and estrogen-receptor-mediated effects. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 111,120, 2006. [source] Aging and lung injury repair: A role for bone marrow derived mesenchymal stem cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2008Ana L. Mora Abstract The incidence of lung fibrosis increases with age. Aging is associated with modifications in the intracellular and extracellular environment including alteration of the extracellular matrix, imbalance of the redox state, accumulation of senescent cells and potential alteration of the recruitment of bone marrow mesenchymal stem cells. The combination of these senescence-related alterations in the lung and in bone marrow progenitor cells might be responsible of the higher susceptibility to lung fibrosis in elderly individuals. The understanding of these age related changes must be considered in the rationale for the development of therapeutic interventions to control lung injury and fibrosis. J. Cell. Biochem. 105: 641,647, 2008. © 2008 Wiley-Liss, Inc. [source] In vivo quantitative proton MRSI study of brain development from childhood to adolescence,JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2002Alena Horská PhD Abstract Purpose To quantify regional variations in metabolite levels in the developing brain using quantitative proton MR spectroscopic imaging (MRSI). Materials and Methods Fifteen healthy subjects three to 19 years old were examined by in vivo multislice proton MRSI. Concentrations of N-acetyl aspartate (NAA), total choline (Cho), total creatine (Cr), and peak area ratios were determined in selected frontal and parietal gray and white matter regions, basal ganglia, and thalamus. Results In cortical gray matter regions, the ratio of NAA/Cho increased to a maximum at 10 years and decreased thereafter (P = 0.010). In contrast, in white matter, average ratios NAA/Cho increased linearly with age (P = 0.045). In individual brain regions, age-related changes in NAA/Cho were found in the putamen (P = 0.044). No significant age-related changes in NAA, Cho, Cr, or other metabolite ratios could be determined. Conclusion Consistent with recent studies using other structural and functional neuroimaging techniques, our data suggest that small but significant changes occur in regional cerebral metabolism during childhood and adolescence. Non-linear age related changes of NAA/Cho in frontal and parietal areas, resembling previously reported age related changes in rates of glucose utilization and cortical volumes, may be associated with dendritic and synaptic development and regression. Linear age-related changes of NAA/Cho in white matter are also in agreement with age-related increases in white matter volumes, and may reflect progressive increases in axonal diameter and myelination. J. Magn. Reson. Imaging 2002;15:137,143. Published 2002 Wiley-Liss, Inc. [source] Relation of Age and Sex to Atrial Electrophysiological Properties in Patients with No History of Atrial FibrillationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2003KOICHI SAKABE Although atrial fibrillation is a common arrhythmia, especially in elderly men, little is known about age related changes in atrial electrophysiological properties or gender differences. The aim of this study was to analyze the effects of aging on vulnerability to atrial fibrillation and assessed gender differences in those age related changes. An electrophysiological study was performed on 73 patients with no history of atrial fibrillation, structural heart disease, or conditions with potential effects on cardiac hemodynamic or electrophysiological function, including 25 women (mean age 49 ± 18 years; range 12,84 years). The following atrial excitability parameters were assessed: spontaneous or paced (A1) and extrastimulated (A2) atrial electrogram widths, percent maximum atrial fragmentation(A2/A1 × 100), effective refractory period, wavelength index (effective refractory period/A2), and inducibility of atrial fibrillation. There were no significant differences in percent maximum atrial fragmentation (143 ± 28vs142 ± 35%), effective refractory period (241 ± 39vs238 ± 50 ms), wavelength index (2.9 ± 0.8vs3.1 ± 0.9), induction of atrial fibrillation (10 [21%] vs 7 [28%]), or age (50 ± 17vs 49 ± 20 years) between men and women. Age was not statistically different between those patients with and without induction of atrial fibrillation in men (48 ± 14vs50 ± 18 years) and women (48 ± 18vs49 ± 21 years). Percent maximum atrial fragmentation and effective refractory period were directly correlated with age in men (r = 0.35, P = 0.01; r = 0.46, P < 0.001, respectively) and women (r = 0.42, P = 0.04; r = 0.45, P = 0.02, respectively), though wavelength index did not correlate with age in men (r =,0.04) or women (r =,0.04) with no history of atrial fibrillation. Considering these findings, the authors conclude that the mechanism triggering atrial fibrillation may be different between older and younger patients with atrial fibrillation, because younger patients who have no marked substrate for atrial fibrillation may need many trigger beats to induce atrial fibrillation. (PACE 2003; 26:1238,1244) [source] 2231: Age-related modifications in RPE cellsACTA OPHTHALMOLOGICA, Issue 2010E MANNERMAA Age-related macular degeneration (AMD) is a multi-factorial polygenetic aging disease. It has been shown that RPE dysfunction predisposes neural retinal dysfunction and the development of choroidal neovascularization. The pathogenesis of age-related macular degeneration (AMD) essentially involves chronic oxidative stress, increased accumulation of lipofuscin in retinal pigment epithelial (RPE) cells and extracellular drusen formation, as well as the presence of chronic inflammation. The capacity to prevent the accumulation of cellular cytotoxic protein aggregates is decreased in senescent cells which may evoke lipofuscin accumulation into lysosomes in postmitotic RPE cells. This presence of lipofuscin decreases lysosomal enzyme activity and impairs autophagic clearance of damaged proteins which should be removed from cells. Proteasomes are another crucial proteolytic machine which degrades especially cellular proteins damaged by oxidative stress. The cross-talk between lysosomes, autophagy and proteasomes in RPE cell protein aggregation, their role as a possible therapeutic target and their involvement in the pathogenesis of AMD is discussed. In addition, age related changes in Bruch's membrane and choroidal blood flow may take part in the pathogenesis of AMD. This will be also discussed. [source] Does internal longitudinal microstructure of retinal veins change with age in medically healthy persons?ACTA OPHTHALMOLOGICA, Issue 2009KE KOTLIAR Purpose We demonstrated previously that roughness of the retinal arterial blood column measured along the vessel axis, termed longitudinal arterial profile (LAP) increases significantly in anamnesticly healthy volunteers with increasing age. Recently we have demonstrated age related changes in LAP of medically healthy persons. Whether longitudinal retinal venous profiles (LVP) are altered with age in this group is investigated. Methods 83 medically healthy volunteers were examined by Dynamic Vessel Analyzer (IMEDOS, Jena, Germany) using stimulation with flickering light. 3 age groups were formed: young (N=28, 30,2±4,3 years), middle age (N=28, 42,3±3,3 years) and seniors (N=27, 64,0±5,0 years). Included in the analysis were volunteers without medical vascular risk factors defined as: blood pressure < 140/90 mmHg, HDL > 35 mg/dl, LDL < 190 mg/dl and glucose levels < 110 mg/dl. Retinal venous diameters were measured along 1 mm vessel segments to obtain LVP. Differences were analyzed using Fourier transformation. Results In all age groups power spectra of LVP do not change during all stages of the venous response to the stimulation. There were no significant differences in LVP between the age groups. Venous diameters in middle-age group were reduced in comparison to the young group at all stages of vessel reaction (p<0,05). Conclusion Our results indicate that in contrast to retinal arteries retinal veins of validated healthy volunteers do not undergo age related microstructural changes. Hence previously reported age related decrease of retinal venous diameter might have physiologic origin due to reduced blood flow in retinal microcirculation with age, not because of structural changes of venous wall. [source] | ||||||||||