AIM:To evaluate the efficacy,timing of retreatment and safety of dexamethasone(DEX)implant on macular edema(ME)secondary to diabetic retinopathy(DME)and retinal vein occlusion(RVO-ME)patients who were refractory to an...AIM:To evaluate the efficacy,timing of retreatment and safety of dexamethasone(DEX)implant on macular edema(ME)secondary to diabetic retinopathy(DME)and retinal vein occlusion(RVO-ME)patients who were refractory to anti-vascular endothelial growth factor(VEGF)treatment.METHODS:This retrospective study included 37 eyes received at least one DEX implant treatment for DME or RVO-ME between January 1,2019,and January 1,2023.These refractory DME and RVO-ME cases received at least 5 anti-VEGF injections and failure to gain more than 5 letters or a significant reduction in central retinal thickness(CRT).The best corrected visual acuity(BCVA)and CRT were measured at baseline,and at 1,3,4 and 6mo post-DEX implant injection.Adverse events such as elevated intraocular pressure(IOP)and cataract were recorded.RESULTS:For RVO cases(n=22),there was a significant increase in BCVA from 0.27±0.19 to 0.35±0.20 at 6mo post-DEX injection(P<0.05)and CRT decreased from 472.1±90.6 to 240.5±39.0μm at 6mo(P<0.0001).DME cases(n=15)experienced an improvement in BCVA from 0.26±0.15 to 0.43±0.20 at 6mo post-DEX implant injection(P=0.0098),with CRT reducing from 445.7±55.7 to 271.7±34.1μm at 6mo(P<0.0001).Elevated IOP occurred in 45.9% of patients but was well-controlled with topical medications.No cases of cataract or other adverse events were reported.CONCLUSION:DEX implants effectively improve BCVA and reduce CRT in refractory DME and RVO-ME.Further research with larger cohorts and longer follow-up periods is needed to confirm these findings and assess long-term outcomes.展开更多
AIM: To detect the possible role of interleukin(IL)-26 in diabetic retinopathy(DR) patients.METHODS: Subjects were divided into diabetes without retinopathy(DWR) group(n=20), non-proliferative diabetic retinopathy(NPD...AIM: To detect the possible role of interleukin(IL)-26 in diabetic retinopathy(DR) patients.METHODS: Subjects were divided into diabetes without retinopathy(DWR) group(n=20), non-proliferative diabetic retinopathy(NPDR) group(n=20), proliferative diabetic retinopathy(PDR) group(n=20) and normal control group(n=20). The protein expression of IL-26 in the serum and vitreous fluid were measured by enzyme-linked immunosorbent assay(ELISA). The m RNA change of IL-26 in peripheral blood mononuclear cells(PBMCs) was assessed by real-time polymerase chain reaction.RESULTS: The serum expression of IL-26 in PDR group was significantly elevated compared with the normal control group, DWR group and NPDR group. The vitreous fluid concentration of IL-26 in PDR patients(without antiVEGF therapy) was also higher compared to normal controls. However, no obvious significance was found concerning the expression of IL-26 in vitreous fluid between PDR after anti-VEGF therapy and normal controls. In PDR group, the m RNA level of IL-26 significantly increased compared with the normal controls and DWR patients in the PBMCs.CONCLUSION: Protein and m RNA expression of IL-26 are increased in serum, vitreous fluid and PBMCs in PDR patients, suggesting that IL-26 may be associated with the pathogenesis of PDR.展开更多
AIM: To examine the expression of high mobility group box-1(HMGB-1) and intercellular adhesion molecule-1(ICAM-1) in the retina and the hippocampal tissues; and further to evaluate the association of these two mo...AIM: To examine the expression of high mobility group box-1(HMGB-1) and intercellular adhesion molecule-1(ICAM-1) in the retina and the hippocampal tissues; and further to evaluate the association of these two molecules with the alterations of blood-retinal barrier(BRB) and blood-brain barrier(BBB) in a rat model of type 2 diabetes.METHODS: The type-2 diabetes mellitus(DM) model was established with a high-fat and high-glucose diet combined with streptozotocin(STZ). Sixteen weeks after DM induction, morphological changes of retina and hippocampus were observed with hematoxylin-eosin staining, and alternations of BRB and BBB permeability were measured using Evans blue method. Levels of HMGB-1 and ICAM-1 in retina and hippocampus were detected by Western blot. Serum HMGB-1 levels were determined by enzyme-linked immunosorbent assay(ELISA).RESULTS: A significantly higher serum fasting blood glucose level in DM rats was observed 2wk after STZ injection(P 〈0.01). The serum levels of fasting insulin,Insulin resistance homeostatic model assessment(IRHOMA),total cholesterol(TC), total triglycerides(TG) and low density lipoprotein cholesterol(LDL-C) in the DM rats significantly higher than those in the controls(all P 〈0.01).HMGB-1(0.96±0.03, P 〈0.01) and ICAM-1(0.76±0.12, P 〈0.05) levels in the retina in the DM rats were significantly higher than those in the controls. HMGB-1(0.83±0.13, P 〈0.01) and ICAM-1(1.15 ±0.08, P 〈0.01) levels in the hippocampal tissues in the DM rats were alsosignificantly higher than those in the controls. Sixteen weeks after induction of DM, the BRB permeability to albumin-bound Evans blue dye in the DM rats was significantly higher than that in the controls(P 〈0.01).However, there was no difference of BBB permeability between the DM rats and controls. When compared to the controls, hematoxylin and eosin staining showed obvious irregularities in the DM rats.CONCLUSION: BRB permeability increases significantly in rats with type-2 DM, which may be associated with the up-regulated retinal expression of HMGB-1 and ICAM-1.展开更多
As a model molecule of actinide chemistry,UO molecule plays an important role in understanding the electronic structure and chemical bonding of actinide-containing species.We report a study of the laser-induced fluore...As a model molecule of actinide chemistry,UO molecule plays an important role in understanding the electronic structure and chemical bonding of actinide-containing species.We report a study of the laser-induced fluorescence spectra of the U^(16)O and U^(18)O using two-dimensional spectroscopy.Several rotationally resolved excitation spectra were investigated.Accurate molecular rotational constants and equilibrium internuclear distances were reported.Low-lying electronic states information was extracted from high resolution dispersed fluorescence spectra and analyzed by the ligand field theory model.The configuration of the ground state was determined as U^(2+)(5 f^(3)7 s)O^(2-).The branching ratios,and the vibrational harmonic and anharmonic parameters were also obtained.Radiative lifetimes were determined by recording the timeresolved fluorescence spectroscopy.Transition dipole moments were calculated using the branching ratios and the radiative lifetimes.These findings were elucidated by using quantum-chemical calculations,and the chemical bonding was also analyzed.The findings presented in this work will enrich our understanding of actinide-containing molecules.展开更多
Existing sequential parameter estimation methods use the acoustic pressure of a line array as observations. The modal dispersion curves are employed to estimate the sound speed profile(SSP) and geoacoustic parameter...Existing sequential parameter estimation methods use the acoustic pressure of a line array as observations. The modal dispersion curves are employed to estimate the sound speed profile(SSP) and geoacoustic parameters based on the ensemble Kalman filter. The warping transform is implemented to the signals received by a single hydrophone to obtain the dispersion curves. The experimental data are collected at a range-independent shallow water site in the South China Sea. The results indicate that the SSPs are well estimated and the geoacoustic parameters are also well determined. Comparisons of the observed and estimated modal dispersion curves show good agreement.展开更多
Dam structures are prime targets during wars,and a tragedy is likely to happen in a populated area downstream of a dam exposed to explosions.However,experimental investigations of the failure of a concrete gravity dam...Dam structures are prime targets during wars,and a tragedy is likely to happen in a populated area downstream of a dam exposed to explosions.However,experimental investigations of the failure of a concrete gravity dam subjected to underwater explosion(UNDEX)are extremely scarce.In this study,centrifuge tests and numerical simulations were performed to investigate the failure of a concrete gravity dam subjected to a near-field UNDEX.The results revealed the existence of two tensile fractures inside the dam,one in the upper part and the other in the lower part.Due to the narrowness of the upper part,there were coupled effects of bending tensile loads in the upstream face and a reflected tensile stress wave in the downstream face,resulting in severe tensile damage to the upper part in both the upstream and downstream faces.The fracture in the lower part was measured at around one third of the height of the dam.This fracture was produced mainly by the bending tensile loads in the upstream face.Driven by those loads,this fracture started from the upstream face and developed towards the downstream face,with a horizontal angle of about 15?.The underlying mechanisms behind the two tensile fractures were confirmed by recorded strain histories.The dam failures presented in this study are similar to those produced in historical wars,in which dams were under similar attack scenarios.展开更多
This paper presents the explosion cratering effects and their propagation laws of blast waves in dry standard sands using a 450 g-t geotechnical centrifuge apparatus.Ten centrifuge model tests were completed with vari...This paper presents the explosion cratering effects and their propagation laws of blast waves in dry standard sands using a 450 g-t geotechnical centrifuge apparatus.Ten centrifuge model tests were completed with various ranges of explosive mass,burial depth and centrifuge accelerations.Eleven accelerometers were installed to record the acceleration response in sand.The dimensions of the explosion craters were measured after the tests.The results demonstrated that the relationship between the dimensionless parameters of cratering efficiency and gravity scaled yield is a power regression function.Three specific function equations were obtained.The results are in general agreement with those obtained by other studies.A scaling law based on the combination of the π terms was used to fit the results of the ten model tests with a correlation coefficient of 0.931.The relationship can be conveniently used to predict the cratering effects in sand.The results also showed that the peak acceleration is a power increasing function of the acceleration level.An empirical exponent relation between the proportional peak acceleration and distance is proposed.The propagation velocity of blast waves is found to be ranged between 200 and 714 m/s.展开更多
An unprecedented enzyme-catalyzed asymmetric domino aza-Michael/aldol reaction of 2-aminobenzaldehyde and a,b-unsaturated aldehydes is achieved. Pepsin from porcine gastric mucosa provided mild and efficient access to...An unprecedented enzyme-catalyzed asymmetric domino aza-Michael/aldol reaction of 2-aminobenzaldehyde and a,b-unsaturated aldehydes is achieved. Pepsin from porcine gastric mucosa provided mild and efficient access to diverse substituted 1,2-dihydroquinolines in yields of 38%–97% with 6%–24%enantiomeric excess(ee). This work not only provides a novel method for the synthesis of dihydroquinoline derivatives, but also promotes the development of enzyme catalytic promiscuity.展开更多
The desulfurization and resulfurization of slag containing oxides of vanadium and titanium(CaO–SiO_(2)–MgO–Al_(2)O_(3)–V_(2)O_(3)–TiO_(2)–FeO)in the pretreatment of semi-steel desulfurization at 1623 K were inve...The desulfurization and resulfurization of slag containing oxides of vanadium and titanium(CaO–SiO_(2)–MgO–Al_(2)O_(3)–V_(2)O_(3)–TiO_(2)–FeO)in the pretreatment of semi-steel desulfurization at 1623 K were investigated.Based on the ionic structure theory of slag,it could be concluded that V_(2)O_(3) and TiO_(2) combined with(O_(2)–)to form complex anions including VO_(3)^(3–),TiO_(4)^(4–),etc.,which reduced the activity of(O_(2)–)and decreased the sulfur partition ratio(LS).And FeO enhanced the activity of[O]at the slag–metal interface,which decreased the desulfurization capacity of the slag.Compared to the binary basicity,the presented basicity expression containing V_(2)O_(3) and TiO_(2) described the relationship between LS and basicity more accurately.Considering the problems of dilute slag,a large amount of residual slag and much resulfurization in the slagging-off process after pretreatment,the effect of CaO+C-based slag modifier on the resulfurization,melting point and viscosity of the desulfurization slag was investigated.It was proposed that adding 5%–10%of the slag modifier to the desulfurization slag after desulfurization decreased the resulfurization effectively.And the added modifier adjusted the slag viscosity well,which helped to reduce iron loss and residual slag.展开更多
To the Editor:A 68-year-old man presented with a 2-month aphasia.Magnetic resonance imaging scan revealed an abnormal signal in the left temporal lobe with heterogenous enhancement[Figure 1A].Glioma was considered,and...To the Editor:A 68-year-old man presented with a 2-month aphasia.Magnetic resonance imaging scan revealed an abnormal signal in the left temporal lobe with heterogenous enhancement[Figure 1A].Glioma was considered,and the patient underwent total tumor resection.Microscopic examination of the resected tumor showed a high-grade glial tumor with pleomorphic cells,elevated mitotic activity,microvascular proliferation,and pseudopalisading necrosis[Figure 1B and Figure 1C].Part of the lesion contained round cells with perinuclear halos.展开更多
基金Supported by the National Natural Science Found of China(No.81870673,No.81800814,No.82201168).
文摘AIM:To evaluate the efficacy,timing of retreatment and safety of dexamethasone(DEX)implant on macular edema(ME)secondary to diabetic retinopathy(DME)and retinal vein occlusion(RVO-ME)patients who were refractory to anti-vascular endothelial growth factor(VEGF)treatment.METHODS:This retrospective study included 37 eyes received at least one DEX implant treatment for DME or RVO-ME between January 1,2019,and January 1,2023.These refractory DME and RVO-ME cases received at least 5 anti-VEGF injections and failure to gain more than 5 letters or a significant reduction in central retinal thickness(CRT).The best corrected visual acuity(BCVA)and CRT were measured at baseline,and at 1,3,4 and 6mo post-DEX implant injection.Adverse events such as elevated intraocular pressure(IOP)and cataract were recorded.RESULTS:For RVO cases(n=22),there was a significant increase in BCVA from 0.27±0.19 to 0.35±0.20 at 6mo post-DEX injection(P<0.05)and CRT decreased from 472.1±90.6 to 240.5±39.0μm at 6mo(P<0.0001).DME cases(n=15)experienced an improvement in BCVA from 0.26±0.15 to 0.43±0.20 at 6mo post-DEX implant injection(P=0.0098),with CRT reducing from 445.7±55.7 to 271.7±34.1μm at 6mo(P<0.0001).Elevated IOP occurred in 45.9% of patients but was well-controlled with topical medications.No cases of cataract or other adverse events were reported.CONCLUSION:DEX implants effectively improve BCVA and reduce CRT in refractory DME and RVO-ME.Further research with larger cohorts and longer follow-up periods is needed to confirm these findings and assess long-term outcomes.
基金Supported by the National Natural Science Foundation of China (No.81870643)
文摘AIM: To detect the possible role of interleukin(IL)-26 in diabetic retinopathy(DR) patients.METHODS: Subjects were divided into diabetes without retinopathy(DWR) group(n=20), non-proliferative diabetic retinopathy(NPDR) group(n=20), proliferative diabetic retinopathy(PDR) group(n=20) and normal control group(n=20). The protein expression of IL-26 in the serum and vitreous fluid were measured by enzyme-linked immunosorbent assay(ELISA). The m RNA change of IL-26 in peripheral blood mononuclear cells(PBMCs) was assessed by real-time polymerase chain reaction.RESULTS: The serum expression of IL-26 in PDR group was significantly elevated compared with the normal control group, DWR group and NPDR group. The vitreous fluid concentration of IL-26 in PDR patients(without antiVEGF therapy) was also higher compared to normal controls. However, no obvious significance was found concerning the expression of IL-26 in vitreous fluid between PDR after anti-VEGF therapy and normal controls. In PDR group, the m RNA level of IL-26 significantly increased compared with the normal controls and DWR patients in the PBMCs.CONCLUSION: Protein and m RNA expression of IL-26 are increased in serum, vitreous fluid and PBMCs in PDR patients, suggesting that IL-26 may be associated with the pathogenesis of PDR.
基金Supported by the Project of Education Bureau Foundation of Hubei Province(No.Q20151901)
文摘AIM: To examine the expression of high mobility group box-1(HMGB-1) and intercellular adhesion molecule-1(ICAM-1) in the retina and the hippocampal tissues; and further to evaluate the association of these two molecules with the alterations of blood-retinal barrier(BRB) and blood-brain barrier(BBB) in a rat model of type 2 diabetes.METHODS: The type-2 diabetes mellitus(DM) model was established with a high-fat and high-glucose diet combined with streptozotocin(STZ). Sixteen weeks after DM induction, morphological changes of retina and hippocampus were observed with hematoxylin-eosin staining, and alternations of BRB and BBB permeability were measured using Evans blue method. Levels of HMGB-1 and ICAM-1 in retina and hippocampus were detected by Western blot. Serum HMGB-1 levels were determined by enzyme-linked immunosorbent assay(ELISA).RESULTS: A significantly higher serum fasting blood glucose level in DM rats was observed 2wk after STZ injection(P 〈0.01). The serum levels of fasting insulin,Insulin resistance homeostatic model assessment(IRHOMA),total cholesterol(TC), total triglycerides(TG) and low density lipoprotein cholesterol(LDL-C) in the DM rats significantly higher than those in the controls(all P 〈0.01).HMGB-1(0.96±0.03, P 〈0.01) and ICAM-1(0.76±0.12, P 〈0.05) levels in the retina in the DM rats were significantly higher than those in the controls. HMGB-1(0.83±0.13, P 〈0.01) and ICAM-1(1.15 ±0.08, P 〈0.01) levels in the hippocampal tissues in the DM rats were alsosignificantly higher than those in the controls. Sixteen weeks after induction of DM, the BRB permeability to albumin-bound Evans blue dye in the DM rats was significantly higher than that in the controls(P 〈0.01).However, there was no difference of BBB permeability between the DM rats and controls. When compared to the controls, hematoxylin and eosin staining showed obvious irregularities in the DM rats.CONCLUSION: BRB permeability increases significantly in rats with type-2 DM, which may be associated with the up-regulated retinal expression of HMGB-1 and ICAM-1.
基金Project supported by the National Natural Science Foundation of China(Grant No.21903050)。
文摘As a model molecule of actinide chemistry,UO molecule plays an important role in understanding the electronic structure and chemical bonding of actinide-containing species.We report a study of the laser-induced fluorescence spectra of the U^(16)O and U^(18)O using two-dimensional spectroscopy.Several rotationally resolved excitation spectra were investigated.Accurate molecular rotational constants and equilibrium internuclear distances were reported.Low-lying electronic states information was extracted from high resolution dispersed fluorescence spectra and analyzed by the ligand field theory model.The configuration of the ground state was determined as U^(2+)(5 f^(3)7 s)O^(2-).The branching ratios,and the vibrational harmonic and anharmonic parameters were also obtained.Radiative lifetimes were determined by recording the timeresolved fluorescence spectroscopy.Transition dipole moments were calculated using the branching ratios and the radiative lifetimes.These findings were elucidated by using quantum-chemical calculations,and the chemical bonding was also analyzed.The findings presented in this work will enrich our understanding of actinide-containing molecules.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11434012,11774374,11404366 and41561144006
文摘Existing sequential parameter estimation methods use the acoustic pressure of a line array as observations. The modal dispersion curves are employed to estimate the sound speed profile(SSP) and geoacoustic parameters based on the ensemble Kalman filter. The warping transform is implemented to the signals received by a single hydrophone to obtain the dispersion curves. The experimental data are collected at a range-independent shallow water site in the South China Sea. The results indicate that the SSPs are well estimated and the geoacoustic parameters are also well determined. Comparisons of the observed and estimated modal dispersion curves show good agreement.
基金Project supported by the National Natural Science Foundation of China(Nos.51879283 , 51339006)。
文摘Dam structures are prime targets during wars,and a tragedy is likely to happen in a populated area downstream of a dam exposed to explosions.However,experimental investigations of the failure of a concrete gravity dam subjected to underwater explosion(UNDEX)are extremely scarce.In this study,centrifuge tests and numerical simulations were performed to investigate the failure of a concrete gravity dam subjected to a near-field UNDEX.The results revealed the existence of two tensile fractures inside the dam,one in the upper part and the other in the lower part.Due to the narrowness of the upper part,there were coupled effects of bending tensile loads in the upstream face and a reflected tensile stress wave in the downstream face,resulting in severe tensile damage to the upper part in both the upstream and downstream faces.The fracture in the lower part was measured at around one third of the height of the dam.This fracture was produced mainly by the bending tensile loads in the upstream face.Driven by those loads,this fracture started from the upstream face and developed towards the downstream face,with a horizontal angle of about 15?.The underlying mechanisms behind the two tensile fractures were confirmed by recorded strain histories.The dam failures presented in this study are similar to those produced in historical wars,in which dams were under similar attack scenarios.
基金supported by the National Natural Science Foundation of China (No. 50779073)the Program Foundation of the China Institute of Water Resources and Hydropower Research (IWHR)(No. YANJI ZD0710)
文摘This paper presents the explosion cratering effects and their propagation laws of blast waves in dry standard sands using a 450 g-t geotechnical centrifuge apparatus.Ten centrifuge model tests were completed with various ranges of explosive mass,burial depth and centrifuge accelerations.Eleven accelerometers were installed to record the acceleration response in sand.The dimensions of the explosion craters were measured after the tests.The results demonstrated that the relationship between the dimensionless parameters of cratering efficiency and gravity scaled yield is a power regression function.Three specific function equations were obtained.The results are in general agreement with those obtained by other studies.A scaling law based on the combination of the π terms was used to fit the results of the ten model tests with a correlation coefficient of 0.931.The relationship can be conveniently used to predict the cratering effects in sand.The results also showed that the peak acceleration is a power increasing function of the acceleration level.An empirical exponent relation between the proportional peak acceleration and distance is proposed.The propagation velocity of blast waves is found to be ranged between 200 and 714 m/s.
基金supported by the National Natural Science Foundation of China (Nos. 21276211 and 21472152)
文摘An unprecedented enzyme-catalyzed asymmetric domino aza-Michael/aldol reaction of 2-aminobenzaldehyde and a,b-unsaturated aldehydes is achieved. Pepsin from porcine gastric mucosa provided mild and efficient access to diverse substituted 1,2-dihydroquinolines in yields of 38%–97% with 6%–24%enantiomeric excess(ee). This work not only provides a novel method for the synthesis of dihydroquinoline derivatives, but also promotes the development of enzyme catalytic promiscuity.
文摘The desulfurization and resulfurization of slag containing oxides of vanadium and titanium(CaO–SiO_(2)–MgO–Al_(2)O_(3)–V_(2)O_(3)–TiO_(2)–FeO)in the pretreatment of semi-steel desulfurization at 1623 K were investigated.Based on the ionic structure theory of slag,it could be concluded that V_(2)O_(3) and TiO_(2) combined with(O_(2)–)to form complex anions including VO_(3)^(3–),TiO_(4)^(4–),etc.,which reduced the activity of(O_(2)–)and decreased the sulfur partition ratio(LS).And FeO enhanced the activity of[O]at the slag–metal interface,which decreased the desulfurization capacity of the slag.Compared to the binary basicity,the presented basicity expression containing V_(2)O_(3) and TiO_(2) described the relationship between LS and basicity more accurately.Considering the problems of dilute slag,a large amount of residual slag and much resulfurization in the slagging-off process after pretreatment,the effect of CaO+C-based slag modifier on the resulfurization,melting point and viscosity of the desulfurization slag was investigated.It was proposed that adding 5%–10%of the slag modifier to the desulfurization slag after desulfurization decreased the resulfurization effectively.And the added modifier adjusted the slag viscosity well,which helped to reduce iron loss and residual slag.
基金This work was supported by the Beijing Excellent Talents Training Project,China(No.201600026833ZK07)the Beijing Higher Education Young Elite Teacher Project,China(No.CIT&TCD201904091)。
文摘To the Editor:A 68-year-old man presented with a 2-month aphasia.Magnetic resonance imaging scan revealed an abnormal signal in the left temporal lobe with heterogenous enhancement[Figure 1A].Glioma was considered,and the patient underwent total tumor resection.Microscopic examination of the resected tumor showed a high-grade glial tumor with pleomorphic cells,elevated mitotic activity,microvascular proliferation,and pseudopalisading necrosis[Figure 1B and Figure 1C].Part of the lesion contained round cells with perinuclear halos.