AIM: To analyze concentrations of vascular endothelial growth factor(VEGF) and fibrosis-related factors in vitreous fluid of proliferative diabetic retinopathy(PDR) patients pretreated with intravitreal anti-VEGF inje...AIM: To analyze concentrations of vascular endothelial growth factor(VEGF) and fibrosis-related factors in vitreous fluid of proliferative diabetic retinopathy(PDR) patients pretreated with intravitreal anti-VEGF injections(IVI) at different time periods prior to pars plana vitrectomy(PPV), and their correlation with the degree of vitreoretinal fibrosis and explore the optimal timing of preoperative IVI.METHODS: The prospective case-control study from January 2019 to July 2020 included 31 eyes with PDRrelated complications(PDR group) and 21 eyes with nondiabetic ocular disease(control group) requiring PPV. PDR eyes were divided into four groups based on timing of PPV: 3 d after IVI(3-day group);5 d after IVI(5-day group);7 or more days after IVI(≥7-day group);and no IVI. Vitreous fluid samples(0.5-1.0 m L) were collected prior to switching on the infusion before routine 23-G PPV. Concentrations of VEGF, basic fibroblast growth factor(b FGF), periostin(PN), interleukin(IL)-6, IL-8, and tumor necrosis factor(TNF)-α were measured by immunoassay, and concentration differences for each cytokine were compared among the groups. The degree of vitreoretinal fibrosis was graded intraoperatively, and the correlation between the changes in cytokine levels and the severity of vitreoretinal fibrosis was analyzed by univariate ordinal logistic regression analysis.RESULTS: PDR eyes without IVI had significantly higher VEGF, b FGF, PN, and IL-6 concentrations than nondiabetic eyes(all P<0.05), and had a significantly higher concentration of VEGF(P<0.05) and a significantly lower concentration of IL-8(P<0.05) than PDR eyes with IVI. Statistically significant differences were also observed for concentrations of VEGF, b FGF, PN, IL-6, and IL-8 among 3-day, 5-day, and ≥7-day groups(all P<0.05);meanwhile there was no significant difference in TNF-α among groups(P=0.226). The 5-day group had the lowest concentration of VEGF and the ≥7-day group had the highest concentration of b FGF and PN. The degree of vitreoretinal fibrosis was significantly higher in the ≥7-day group compared to the 3-day(P=0.015) and 5-day group(P=0.039), and vitreoretinal fibrosis correlated significantly with concentrations of b FGF, PN, IL-6, and IL-8(all P<0.05). Univariate ordinal logistic regression analysis showed that b FGF was an independent risk factor for the severity of vitreoretinal fibrosis in PDR patients pre-treated with IVI.CONCLUSION: The vitreous concentrations of VEGF, b FGF, PN, IL-6, and IL-8 change after pretreatment with IVI before PPV in PDR patients. The degree of vitreoretinal fibrosis is higher in patients with a longer time between IVI treatment and PPV, which may be related to the angiofibrosis switch. The results suggest that PPV should be performed 5 d after IVI administration in PDR patients.展开更多
The oceans are the largest carbon pools on Earth, and play the role of a "buffer" in climate change. Blue carbon, the carbon(mainly organic carbon) captured by marine ecosystems, is one of the important mech...The oceans are the largest carbon pools on Earth, and play the role of a "buffer" in climate change. Blue carbon, the carbon(mainly organic carbon) captured by marine ecosystems, is one of the important mechanisms of marine carbon storage.Blue carbon was initially recognized only in the form of visible coastal plant carbon sequestration. In fact, microorganisms(phytoplankton, bacteria, archaea, viruses, and protozoa), which did not receive much attention in the past, account for more than 90% of the total marine biomass and are the main contributors to blue carbon. Chinese coastal seas, equivalent to 1/3 of China's total land area, have a huge carbon sink potential needing urgently research and development. In this paper, we focus on the processes and mechanisms of coastal ocean's carbon sequestration and the approaches for increasing that sequestration. We discuss the structures of coastal ecosystems, the processes of carbon cycle, and the mechanisms of carbon sequestration. Using the evolution of coastal ocean's carbon sinks in sedimentary records over geologic times, we also discuss the possible effects of natural processes and anthropogenic activities on marine carbon sinks. Finally, we discuss the prospect of using carbon sequestration engineering for increasing coastal ocean's carbon storage capacity.展开更多
基金Supported by the Guiding Science and Technology Plan Project of Huainan City(No.2020044)Construction Project of Key Medical and Health of Anhui Province in 2021。
文摘AIM: To analyze concentrations of vascular endothelial growth factor(VEGF) and fibrosis-related factors in vitreous fluid of proliferative diabetic retinopathy(PDR) patients pretreated with intravitreal anti-VEGF injections(IVI) at different time periods prior to pars plana vitrectomy(PPV), and their correlation with the degree of vitreoretinal fibrosis and explore the optimal timing of preoperative IVI.METHODS: The prospective case-control study from January 2019 to July 2020 included 31 eyes with PDRrelated complications(PDR group) and 21 eyes with nondiabetic ocular disease(control group) requiring PPV. PDR eyes were divided into four groups based on timing of PPV: 3 d after IVI(3-day group);5 d after IVI(5-day group);7 or more days after IVI(≥7-day group);and no IVI. Vitreous fluid samples(0.5-1.0 m L) were collected prior to switching on the infusion before routine 23-G PPV. Concentrations of VEGF, basic fibroblast growth factor(b FGF), periostin(PN), interleukin(IL)-6, IL-8, and tumor necrosis factor(TNF)-α were measured by immunoassay, and concentration differences for each cytokine were compared among the groups. The degree of vitreoretinal fibrosis was graded intraoperatively, and the correlation between the changes in cytokine levels and the severity of vitreoretinal fibrosis was analyzed by univariate ordinal logistic regression analysis.RESULTS: PDR eyes without IVI had significantly higher VEGF, b FGF, PN, and IL-6 concentrations than nondiabetic eyes(all P<0.05), and had a significantly higher concentration of VEGF(P<0.05) and a significantly lower concentration of IL-8(P<0.05) than PDR eyes with IVI. Statistically significant differences were also observed for concentrations of VEGF, b FGF, PN, IL-6, and IL-8 among 3-day, 5-day, and ≥7-day groups(all P<0.05);meanwhile there was no significant difference in TNF-α among groups(P=0.226). The 5-day group had the lowest concentration of VEGF and the ≥7-day group had the highest concentration of b FGF and PN. The degree of vitreoretinal fibrosis was significantly higher in the ≥7-day group compared to the 3-day(P=0.015) and 5-day group(P=0.039), and vitreoretinal fibrosis correlated significantly with concentrations of b FGF, PN, IL-6, and IL-8(all P<0.05). Univariate ordinal logistic regression analysis showed that b FGF was an independent risk factor for the severity of vitreoretinal fibrosis in PDR patients pre-treated with IVI.CONCLUSION: The vitreous concentrations of VEGF, b FGF, PN, IL-6, and IL-8 change after pretreatment with IVI before PPV in PDR patients. The degree of vitreoretinal fibrosis is higher in patients with a longer time between IVI treatment and PPV, which may be related to the angiofibrosis switch. The results suggest that PPV should be performed 5 d after IVI administration in PDR patients.
基金supported by the National Key Research Programs (Grant Nos. 2013CB955700 & 2016YFA0601400)the National Natural Science Foundation of China (Grant Nos. 41422603, 41676125 and 91428308)the National Programme on Global Change and Air-Sea Interaction (Grant No. GASI-0301-02-03)
文摘The oceans are the largest carbon pools on Earth, and play the role of a "buffer" in climate change. Blue carbon, the carbon(mainly organic carbon) captured by marine ecosystems, is one of the important mechanisms of marine carbon storage.Blue carbon was initially recognized only in the form of visible coastal plant carbon sequestration. In fact, microorganisms(phytoplankton, bacteria, archaea, viruses, and protozoa), which did not receive much attention in the past, account for more than 90% of the total marine biomass and are the main contributors to blue carbon. Chinese coastal seas, equivalent to 1/3 of China's total land area, have a huge carbon sink potential needing urgently research and development. In this paper, we focus on the processes and mechanisms of coastal ocean's carbon sequestration and the approaches for increasing that sequestration. We discuss the structures of coastal ecosystems, the processes of carbon cycle, and the mechanisms of carbon sequestration. Using the evolution of coastal ocean's carbon sinks in sedimentary records over geologic times, we also discuss the possible effects of natural processes and anthropogenic activities on marine carbon sinks. Finally, we discuss the prospect of using carbon sequestration engineering for increasing coastal ocean's carbon storage capacity.
