Background: Fibulin- 5 was recently found as a secreted extracellular matrix protein that functions as a scaffold for elastic fibres. However, the distribution of fibulin- 5 in human skin and its changes during the ag...Background: Fibulin- 5 was recently found as a secreted extracellular matrix protein that functions as a scaffold for elastic fibres. However, the distribution of fibulin- 5 in human skin and its changes during the ageing process are not known. Objectives: To explore the involvement of fibulin- 5 in skin ageing, the age- dependent changes in fibulin- 5 localization in human skin were examined compared with those of other elastic fibre components including elastin, fibrillin- 1 and fibulin- 2. Methods: The distribution of elastin, fibrillin- 1, fibrillin- 2, fibulin- 2 and fibulin- 5 was investigated by means of immunohistochemistry using their specific antibodies. Skin samples were recovered from 12 healthy subjects undergoing plastic surgery. Ultraviolet (UV) B- irradiated or control nonirradiated buttock skin samples were obtained from two healthy volunteers at 2 days after the irradiation at 2 minimal erythemal doses. Results: In the reticular dermis of young sun- protected skin from the upper arm, fibulin- 5 colocalized with the other elastic fibre components, while in the papillary dermis fibulin- 5 showed candelabra- like structures perpendicular to the epidermiswith an unstained area just beneath the epidermis, which was similar to that of elastin but not fibrillin- 1. Fibulin- 5 in the reticular dermis decreased and disappeared with age even in sun- protected skin from the thigh, abdomen and upper arm. In sun- exposed skin, fibulin- 5 was extremely reduced in the dermis of cheek skin even from a 20- year- old man. UVB irradiation reduced fibulin- 5, fibulin- 2 and elastin markedly, moderately and weakly, respectively, compared with levels in control nontreated skin. Interestingly, the deposition of fibulin- 5 was increased in solar elastosis, like that of other elastic fibre components. Conclusions: These results suggest that fibulin- 5 is a good marker of skin ageing and that the earlier loss of fibulin- 5 may involve age- dependent changes in other elastic fibre components.展开更多
Objective:This study aimed to employ time‐resolved spectroscopy(TRS)to explore age‐related differences in prefrontal cortex(PFC)activity while subjects performed a working memory task.Methods:We employed TRS to meas...Objective:This study aimed to employ time‐resolved spectroscopy(TRS)to explore age‐related differences in prefrontal cortex(PFC)activity while subjects performed a working memory task.Methods:We employed TRS to measure PFC activity in ten healthy younger and ten healthy older subjects while they performed a working memory(WM)task.All subjects performed the Sternberg test(ST)in which the memory‐set size varied between one and six digits.Using TRS,we recorded changes in cerebral blood oxygenation as a measure of changes in PFC activity during the task.In order to identify left/right asymmetry of PFC activity during the working memory task,we calculated the laterality score,i.e.,Δoxy‐Hb(rightΔoxy‐Hb—leftΔoxy‐Hb);positive values indicate greater activity in the right PFC,while negative values indicate greater activity in the left PFC.Results:During the ST,statistical analyses showed no significant differences between the younger and older groups in accuracy for low memory‐load and high memory‐load.In high memory‐load tasks,however,older subjects were slower than younger subjects(P<0.05).We found that the younger group showed right lateral responses with a stronger right than left activation in the frontal pole,whereas the older group showed bilateral responses(P<0.05).Conclusions:The present results are consistent with the hemispheric asymmetry reduction in older adults(HAROLD)model;working memory tasks cause asymmetrical PFC activation in younger adults,while older adults tend to show reduced hemispheric lateralization.展开更多
文摘Background: Fibulin- 5 was recently found as a secreted extracellular matrix protein that functions as a scaffold for elastic fibres. However, the distribution of fibulin- 5 in human skin and its changes during the ageing process are not known. Objectives: To explore the involvement of fibulin- 5 in skin ageing, the age- dependent changes in fibulin- 5 localization in human skin were examined compared with those of other elastic fibre components including elastin, fibrillin- 1 and fibulin- 2. Methods: The distribution of elastin, fibrillin- 1, fibrillin- 2, fibulin- 2 and fibulin- 5 was investigated by means of immunohistochemistry using their specific antibodies. Skin samples were recovered from 12 healthy subjects undergoing plastic surgery. Ultraviolet (UV) B- irradiated or control nonirradiated buttock skin samples were obtained from two healthy volunteers at 2 days after the irradiation at 2 minimal erythemal doses. Results: In the reticular dermis of young sun- protected skin from the upper arm, fibulin- 5 colocalized with the other elastic fibre components, while in the papillary dermis fibulin- 5 showed candelabra- like structures perpendicular to the epidermiswith an unstained area just beneath the epidermis, which was similar to that of elastin but not fibrillin- 1. Fibulin- 5 in the reticular dermis decreased and disappeared with age even in sun- protected skin from the thigh, abdomen and upper arm. In sun- exposed skin, fibulin- 5 was extremely reduced in the dermis of cheek skin even from a 20- year- old man. UVB irradiation reduced fibulin- 5, fibulin- 2 and elastin markedly, moderately and weakly, respectively, compared with levels in control nontreated skin. Interestingly, the deposition of fibulin- 5 was increased in solar elastosis, like that of other elastic fibre components. Conclusions: These results suggest that fibulin- 5 is a good marker of skin ageing and that the earlier loss of fibulin- 5 may involve age- dependent changes in other elastic fibre components.
基金Supported by the Strategic Research Foundation Grant-aided Project for Private Universities(No.S1411017)a Grant-in-Aid for Exploratory Research(No.25560356)from the Ministry of Education,Culture,Sports,Sciences,and Technology of Japan
文摘Objective:This study aimed to employ time‐resolved spectroscopy(TRS)to explore age‐related differences in prefrontal cortex(PFC)activity while subjects performed a working memory task.Methods:We employed TRS to measure PFC activity in ten healthy younger and ten healthy older subjects while they performed a working memory(WM)task.All subjects performed the Sternberg test(ST)in which the memory‐set size varied between one and six digits.Using TRS,we recorded changes in cerebral blood oxygenation as a measure of changes in PFC activity during the task.In order to identify left/right asymmetry of PFC activity during the working memory task,we calculated the laterality score,i.e.,Δoxy‐Hb(rightΔoxy‐Hb—leftΔoxy‐Hb);positive values indicate greater activity in the right PFC,while negative values indicate greater activity in the left PFC.Results:During the ST,statistical analyses showed no significant differences between the younger and older groups in accuracy for low memory‐load and high memory‐load.In high memory‐load tasks,however,older subjects were slower than younger subjects(P<0.05).We found that the younger group showed right lateral responses with a stronger right than left activation in the frontal pole,whereas the older group showed bilateral responses(P<0.05).Conclusions:The present results are consistent with the hemispheric asymmetry reduction in older adults(HAROLD)model;working memory tasks cause asymmetrical PFC activation in younger adults,while older adults tend to show reduced hemispheric lateralization.
