Retinitis pigmentosa(RP)is a group of heredofamilial retinal diseases which is characterized by night blindness and progressive visual field loss.This study aims to study the treatment effect of Lycium barbarum(LB)on ...Retinitis pigmentosa(RP)is a group of heredofamilial retinal diseases which is characterized by night blindness and progressive visual field loss.This study aims to study the treatment effect of Lycium barbarum(LB)on retinal functions and structure of RP patients.The study is a double-masked randomized controlled trial.RP subjects received scheduled eye examination including visual acuity(VA),Humphrey field analysis(HFA),ganzfeld flash electroretinogram(ffERG)and optical coherence tomography(OCT).The suitable subjects were randomly allocated to either LB-treatment or placebo groups with the supply of LB or placebo for 12 months.There were total 41 RP subjects(22 in LB group and 19 in placebo group)completed the 12 months intervention.The compliance rates for LB and placebo groups were 89.8%±12.5%and 85.3%±7.7%respectively.As compared with placebo group,there were no deteriorations of both high and low contrast VA in LB group(P<0.01).In addition,certain improvements of scotopic rod response and photopic cone response of ffERG were obtained in LB group(P<0.05).In the OCT measurement,an obvious thinning of macular thickness was observed in placebo group but not found in LB group(P<0.05).However,there were no changes found in the sensitivity of central visual field between two groups.Our results confirm that the 12-month LB treatment for RP patients had neuroprotective effect on retina and is believed to delay or minimize the deterioration of visual function in RP.展开更多
Intracellular recordings were made from luminosity-type horizontal cells (LHCs) in the isolated superfused carp retina and the effect of AMPA (α-amino-3-hydroxy-5-methylisoxa-zole-4-propionic acid), a glutamate recep...Intracellular recordings were made from luminosity-type horizontal cells (LHCs) in the isolated superfused carp retina and the effect of AMPA (α-amino-3-hydroxy-5-methylisoxa-zole-4-propionic acid), a glutamate receptor agonist, on these cells was studied. AMPA suppressed the responses of LHCs driven by red-sensitive (R-) cones whereas it potentiated the responses driven by green-sensitive (G-) cones. The AMPA effect could be completely blocked by GYKI 53655, a specific AMPA receptor antagonist, indicating the exclusive involvement of AMPA-preferring receptors. The AMPA effect persisted in the presence of picrotoxin (PTX) or di-hydrokainic acid (DHK), suggesting that the feedback from LHCs onto cones and glutamate transporters on cones may not be involved. It is suggested that there may exist different AMPA receptor subtypes with distinct characteristics on LHCs, which mediate signal transfer from R- and G-cones to LHCs, respectively.展开更多
The biological patterning of the drosophila retina in vivo has striking resemblance to liquid bubbles, in which the surface mechanics due to N-cadherin within a sub-group of retina cells can be mimicked by surface ten...The biological patterning of the drosophila retina in vivo has striking resemblance to liquid bubbles, in which the surface mechanics due to N-cadherin within a sub-group of retina cells can be mimicked by surface tension. In this work, the aggregating patterns were reasonably simplified into 2D clusters consisting of 2—6 identical bubbles confined within a shrinking boundary. By using a hybrid fluid dy-namics model proposed for liquid foams, the aggregating process of 2―6 retina cells was studied. Assuming the minimal perimeter for patterning cells to be the condition of stability patterns, the stable converged patterns we simulated in this work are the same as the experimental observations. More importantly, a new pattern of 6 cells was obtained which was found physically more stable than the other two reported by Hayashi and Carthew[1]. Aggregating perimeters of cells, i.e. the surface energy, showed a good linear fit with the cell numbers.展开更多
基金Health and Medical Research Fund(01121876)and PolyU Internal Grants(G-YBBS,G-YBGS,Z-0GF).
文摘Retinitis pigmentosa(RP)is a group of heredofamilial retinal diseases which is characterized by night blindness and progressive visual field loss.This study aims to study the treatment effect of Lycium barbarum(LB)on retinal functions and structure of RP patients.The study is a double-masked randomized controlled trial.RP subjects received scheduled eye examination including visual acuity(VA),Humphrey field analysis(HFA),ganzfeld flash electroretinogram(ffERG)and optical coherence tomography(OCT).The suitable subjects were randomly allocated to either LB-treatment or placebo groups with the supply of LB or placebo for 12 months.There were total 41 RP subjects(22 in LB group and 19 in placebo group)completed the 12 months intervention.The compliance rates for LB and placebo groups were 89.8%±12.5%and 85.3%±7.7%respectively.As compared with placebo group,there were no deteriorations of both high and low contrast VA in LB group(P<0.01).In addition,certain improvements of scotopic rod response and photopic cone response of ffERG were obtained in LB group(P<0.05).In the OCT measurement,an obvious thinning of macular thickness was observed in placebo group but not found in LB group(P<0.05).However,there were no changes found in the sensitivity of central visual field between two groups.Our results confirm that the 12-month LB treatment for RP patients had neuroprotective effect on retina and is believed to delay or minimize the deterioration of visual function in RP.
基金the National Programme of Basic Research sponsored by the Ministryof Science and Technology of China (G1999054000), the National Foundation of Natural Science of China (No. 39800041), the Shanghai Metropolitan Fund for Development of Science and Techno
文摘Intracellular recordings were made from luminosity-type horizontal cells (LHCs) in the isolated superfused carp retina and the effect of AMPA (α-amino-3-hydroxy-5-methylisoxa-zole-4-propionic acid), a glutamate receptor agonist, on these cells was studied. AMPA suppressed the responses of LHCs driven by red-sensitive (R-) cones whereas it potentiated the responses driven by green-sensitive (G-) cones. The AMPA effect could be completely blocked by GYKI 53655, a specific AMPA receptor antagonist, indicating the exclusive involvement of AMPA-preferring receptors. The AMPA effect persisted in the presence of picrotoxin (PTX) or di-hydrokainic acid (DHK), suggesting that the feedback from LHCs onto cones and glutamate transporters on cones may not be involved. It is suggested that there may exist different AMPA receptor subtypes with distinct characteristics on LHCs, which mediate signal transfer from R- and G-cones to LHCs, respectively.
基金the National Natural Science Foundation of China (Grant Nos. 20336040 and 20490201)
文摘The biological patterning of the drosophila retina in vivo has striking resemblance to liquid bubbles, in which the surface mechanics due to N-cadherin within a sub-group of retina cells can be mimicked by surface tension. In this work, the aggregating patterns were reasonably simplified into 2D clusters consisting of 2—6 identical bubbles confined within a shrinking boundary. By using a hybrid fluid dy-namics model proposed for liquid foams, the aggregating process of 2―6 retina cells was studied. Assuming the minimal perimeter for patterning cells to be the condition of stability patterns, the stable converged patterns we simulated in this work are the same as the experimental observations. More importantly, a new pattern of 6 cells was obtained which was found physically more stable than the other two reported by Hayashi and Carthew[1]. Aggregating perimeters of cells, i.e. the surface energy, showed a good linear fit with the cell numbers.
