Background : Scleral fixation of intraocular lenses is a surgical technique that involves anchoring an artificial lens to the sclera. Traditional approaches, such as capsular bag placement, may not be feasible in cert...Background : Scleral fixation of intraocular lenses is a surgical technique that involves anchoring an artificial lens to the sclera. Traditional approaches, such as capsular bag placement, may not be feasible in certain situations, making scleral fixation a valuable alternative. The scleral reactions to different types of suture materials are not fully understood. Therefore, the present study describes the microscopic structure of normal scleral tissue and its changes with suture materials. Methods : We compared six groups of rabbit eyes focusing on the sclera: group with polytetrafluoroethylene( PTFE) chain, PTFE fiber, polypropylene( PPE) fiber and control groups. multilevel sampling and stereological methods were used for histological quantification of the leukocyte infiltration fractions and type Ⅰ and type Ⅲ collagen. Results : Quantitative histological evaluation revealed the following:(1) For all materials used, inflammation was present in the surrounding scleral tissue compared with healthy controls. However, leukocyte infiltration in the sclera was not statistically different between the materials.(2) As part of the evaluation of collagen, the greatest changes occurred in the PTFE fiber group at 2 weeks postoperatively. In the PTFE chain group, more significant changes were visible at 4 weeks.(3) The changes in the PPE fiber group compared to healthy scleral tissue were the least significant. Conclusions : From a histological point of view, it is evident that there are differences in the quantitative parameters between the untouched sclera and the sclera with suture material. Furthermore, distinctions were observed among various materials and across different time intervals.展开更多
Background: SIRT1 histone deacetylase acts on many epigenetic and non-epigenetic targets. It is thought that SIRT1 is involved in oocyte maturation;therefore, the importance of the ooplasmic SIRT1 pool for the further...Background: SIRT1 histone deacetylase acts on many epigenetic and non-epigenetic targets. It is thought that SIRT1 is involved in oocyte maturation;therefore, the importance of the ooplasmic SIRT1 pool for the further fate of mature oocytes has been strongly suggested. We hypothesised that SIRT1 plays the role of a signalling molecule in mature oocytes through selected epigenetic and non-epigenetic regulation.Results: We observed SIRT1 re-localisation in mature oocytes and its association with spindle microtubules.In mature oocytes, SIRT1 distribution shows a spindle-like pattern, and spindle-specific SIRT1 action decreasesα-tubulin acetylation. Based on the observation of the histone code in immature and mature oocytes, we suggest that SIRT1 is mostly predestined for an epigenetic mode of action in the germinal vesicles(GVs) of immature oocytes. Accordingly, BML-278-driven trimethylation of lysine K9 in histone H3 in mature oocytes is considered to be a result of GV epigenetic transformation.Conclusions: Taken together, our observations point out the dual spatiotemporal SIRT1 action in oocytes,which can be readily switched from the epigenetic to non-epigenetic mode of action depending on the progress of meiosis.展开更多
基金supported by the Charles University Cooperatio Program,Research Areas MED/DIAG,and Surgical Disciplinessupport from the Ministry of Education,Youth,and Sports of the Czech Republic under Project FIND No.CZ.02.1.01/0.0/0.0/16_019/0000787.L.V.was also supported by Charles University SVV-2025260773.
文摘Background : Scleral fixation of intraocular lenses is a surgical technique that involves anchoring an artificial lens to the sclera. Traditional approaches, such as capsular bag placement, may not be feasible in certain situations, making scleral fixation a valuable alternative. The scleral reactions to different types of suture materials are not fully understood. Therefore, the present study describes the microscopic structure of normal scleral tissue and its changes with suture materials. Methods : We compared six groups of rabbit eyes focusing on the sclera: group with polytetrafluoroethylene( PTFE) chain, PTFE fiber, polypropylene( PPE) fiber and control groups. multilevel sampling and stereological methods were used for histological quantification of the leukocyte infiltration fractions and type Ⅰ and type Ⅲ collagen. Results : Quantitative histological evaluation revealed the following:(1) For all materials used, inflammation was present in the surrounding scleral tissue compared with healthy controls. However, leukocyte infiltration in the sclera was not statistically different between the materials.(2) As part of the evaluation of collagen, the greatest changes occurred in the PTFE fiber group at 2 weeks postoperatively. In the PTFE chain group, more significant changes were visible at 4 weeks.(3) The changes in the PPE fiber group compared to healthy scleral tissue were the least significant. Conclusions : From a histological point of view, it is evident that there are differences in the quantitative parameters between the untouched sclera and the sclera with suture material. Furthermore, distinctions were observed among various materials and across different time intervals.
基金supported by the Charles University Research Fund(Progres Q39)the National Sustainability Programme I(NPU I)Nr.LO1503 provided by the Ministry of Education+5 种基金Youth and Sports of the Czech Republic(MEYS CR)project No.SVV 02690 awarded by MEYS CRthe project No.CZ.02.1.01/0.0/0.0/16_019/0000787 “Fighting Infectious Diseases”awarded by MEYS CR and financed from The European Regional Development Fundsupported by the National Agency of Agriculture Sciences(NAZV QJ1510138)the Czech Ministry of Agriculture(MZe RO 0718)
文摘Background: SIRT1 histone deacetylase acts on many epigenetic and non-epigenetic targets. It is thought that SIRT1 is involved in oocyte maturation;therefore, the importance of the ooplasmic SIRT1 pool for the further fate of mature oocytes has been strongly suggested. We hypothesised that SIRT1 plays the role of a signalling molecule in mature oocytes through selected epigenetic and non-epigenetic regulation.Results: We observed SIRT1 re-localisation in mature oocytes and its association with spindle microtubules.In mature oocytes, SIRT1 distribution shows a spindle-like pattern, and spindle-specific SIRT1 action decreasesα-tubulin acetylation. Based on the observation of the histone code in immature and mature oocytes, we suggest that SIRT1 is mostly predestined for an epigenetic mode of action in the germinal vesicles(GVs) of immature oocytes. Accordingly, BML-278-driven trimethylation of lysine K9 in histone H3 in mature oocytes is considered to be a result of GV epigenetic transformation.Conclusions: Taken together, our observations point out the dual spatiotemporal SIRT1 action in oocytes,which can be readily switched from the epigenetic to non-epigenetic mode of action depending on the progress of meiosis.
