Dementia is a clinical syndrome that affects approximately 47 million people worldwide and is characterized by progressive and irreversible decline of cognitive,behavioral and sesorimotor functions.Alzheimer’s diseas...Dementia is a clinical syndrome that affects approximately 47 million people worldwide and is characterized by progressive and irreversible decline of cognitive,behavioral and sesorimotor functions.Alzheimer’s disease(AD)accounts for approximately 60–80%of all cases of dementia,and neuropathologically is characterized by extracellular deposits of insoluble amyloid-β(Aβ)and intracellular aggregates of hyperphosphorylated tau.Significantly,although for a long time it was believed that the extracellular accumulation of Aβwas the culprit of the symptoms observed in these patients,more recent studies have shown that cognitive decline in people suffering this disease is associated with soluble Aβ-induced synaptic dysfunction instead of the formation of insoluble Aβ-containing extracellular plaques.These observations are translationally relevant because soluble Aβ-induced synaptic dysfunction is an early event in AD that precedes neuronal death,and thus is amenable to therapeutic interventions to prevent cognitive decline before the progression to irreversible brain damage.The plasminogen activating(PA)system is an enzymatic cascade that triggers the degradation of fibrin by catalyzing the conversion of plasminogen into plasmin via two serine proteinases:tissue-type plasminogen activator(tPA)and urokinase-type plasminogen activator(uPA).Experimental evidence reported over the last three decades has shown that tPA and uPA play a role in the pathogenesis of AD.However,these studies have focused on the ability of these plasminogen activators to trigger plasmin-induced cleavage of insoluble Aβ-containing extracellular plaques.In contrast,recent evidence indicates that activity-dependent release of uPA from the presynaptic terminal of cerebral cortical neurons protects the synapse from the deleterious effects of soluble Aβvia a mechanism that does not require plasmin generation or the cleavage of Aβfibrils.Below we discuss the role of the PA system in the pathogenesis of AD and the translational relevance of data published to this date.展开更多
Membrane depolarization induces the release of the serine proteinase tissue-type plasminogen activator（t PA） from the presynaptic terminal of cerebral cortical neurons.Once in the synaptic cleft this t PA promotes t...Membrane depolarization induces the release of the serine proteinase tissue-type plasminogen activator（t PA） from the presynaptic terminal of cerebral cortical neurons.Once in the synaptic cleft this t PA promotes the exocytosis and subsequent endocytic retrieval of glutamate-containing synaptic vesicles,and regulates the postsynaptic response to the presynaptic release of glutamate.Indeed,t PA has a bidirectional effect on the composition of the postsynaptic density（PSD） that does not require plasmin generation or the presynaptic release of glutamate,but varies according to the baseline level of neuronal activity.Hence,in inactive neurons t PA induces phosphorylation and accumulation in the PSD of the Ca^（2＋）/calmodulin-dependent protein kinase IIα（pCa MKIIα）,followed by pCa MKIIα-induced phosphorylation and synaptic recruitment of Glu R1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid（AMPA） receptors.In contrast,in active neurons with increased levels of pCa MKIIα in the PSD t PA induces pCa MKIIα and p Glu R1 dephosphorylation and their subsequent removal from the PSD.These effects require active synaptic N-methyl-D-aspartate（NMDA） receptors and cyclin-dependent kinase 5（Cdk5）-induced phosphorylation of the protein phosphatase 1（PP1） at T320.These data indicate that t PA is a homeostatic regulator of the postsynaptic response of cerebral cortical neurons to the presynaptic release of glutamate via bidirectional regulation of the pCa MKIIα/PP1 switch in the PSD.展开更多
Primary focal and segmental glomerulosclerosis(FSGS) may be due to genetic or acquired etiologies and is a common cause of nephrotic syndrome with high morbidity that often leads to end-stage renal failure. The differ...Primary focal and segmental glomerulosclerosis(FSGS) may be due to genetic or acquired etiologies and is a common cause of nephrotic syndrome with high morbidity that often leads to end-stage renal failure. The different available therapeutic approaches are unsuccessful, in part due to partially deciphered heterogeneous and complex pathophysiological mechanisms. Moreover, the term FSGS, even in its primary form, comprises a histological description shared by a number of different causes with completely different molecular pathways of disease. This review focuses on the latest developments regarding the pathophysiology of primary acquired FSGS caused by soluble factor urokinase type plasminogen activator receptor, a circulating permeability factor involved in proteinuria and edema formation, and describes recent advances with potential success in therapy.展开更多
组织型纤溶酶原激活剂(tissue type plasmin activator,tPA)是美国食品药品监督管理局唯一批准的用于急性缺血性卒中治疗的药物,但由于治疗时间窗狭窄以及会导致严重的出血性转化(hemorrhagic transformation,HT),其临床应用受到限制。...组织型纤溶酶原激活剂(tissue type plasmin activator,tPA)是美国食品药品监督管理局唯一批准的用于急性缺血性卒中治疗的药物,但由于治疗时间窗狭窄以及会导致严重的出血性转化(hemorrhagic transformation,HT),其临床应用受到限制。本文拟从血脑屏障破坏、神经炎症、氧化应激以及亚硝酸应激等方面对HT发展的机制及近7年来发表在国内外期刊上的小分子化合物对HT保护的研究进展予以综述,为缺血性中风的新药开发和药物联用提供一定参考。展开更多
Aberrant expression of annexin A2-SI00A10 heterotetramer （AIIt） associated with PML/RARα fusion protein causes lethal hyperfibrinolysis in acute promyelocytic leukemia （APL）, but the mechanism is unclear. To faci...Aberrant expression of annexin A2-SI00A10 heterotetramer （AIIt） associated with PML/RARα fusion protein causes lethal hyperfibrinolysis in acute promyelocytic leukemia （APL）, but the mechanism is unclear. To facilitate the investigation of regulatory association between ANXA2 and promyelocytic leukemia/retinoic acid receptor α （PML/RARα） fusion protein, this work was performed to determine the transcription start site of ANXA2 promoter with rapid amplification of 5＇-cDNA ends analysis. Zinc-induced U937/PR9 cells expressed PML/RARα fusion protein, and resultant increases in ANXA2 transcripts and translational expressions of both ANXA2 and S100A10, while S100A10 transcripts remained constitutive. The transactivation of ANXA2 promoter by PML/RARα fusion protein was 3.29 ± 0.13 fold higher than that by control pSG5 vector or wild-type RARer. The overexpression of ANXA2 in U937 transfected with full-length ANXA2 cDNA was associated with increased S100A10 subunit, although S100A10 transcripts remained constitutive. The tPA-dependent initial rate of plasmin generation （IRPG） in zinc-treated U937/PR9 increased by 2.13-fold, and cell invasiveness increased by 27.6%. Antibodies against ANXA2, S100A10, or combination of both all remarkably inhibited the IRPG and invasiveness in U937/PR9 and NB4. Treatment of zinc-induced U937/PR9 or circulating APL blasts with all-trans retinoic acid （ATRA） significantly reduced cell surface ANXA2 and S100A10 and associated reductions in IRPG and invasiveness. Thus, PML/RARα fusion protein transactivated the ANXA2 promoter to upregulate ANXA2 and accumulate S100A10. Increased AIIt promoted IRPG and invasiveness, both of which were partly abolished by antibodies against ANXA2 and S100A10 or by ATRA.展开更多
目的探讨溶栓胶囊联合阿司匹林治疗颈动脉硬化斑块的疗效。方法选取100例颈动脉粥样硬化斑块患者作为研究对象,用随机数字表法分为观察组(55例,用溶栓胶囊联合阿司匹林肠溶片治疗)和对照组(45例,用阿司匹林肠溶片治疗)。观察2组治疗后...目的探讨溶栓胶囊联合阿司匹林治疗颈动脉硬化斑块的疗效。方法选取100例颈动脉粥样硬化斑块患者作为研究对象,用随机数字表法分为观察组(55例,用溶栓胶囊联合阿司匹林肠溶片治疗)和对照组(45例,用阿司匹林肠溶片治疗)。观察2组治疗后的临床疗效、斑块情况、中医症状积分、血流变指标和不良反应发生情况。结果治疗后,观察组的临床总有效率(96.36%)高于对照组(80.00%),P<0.05。观察组患者的内-中膜的厚度(intima media thickness,IMT)和斑块面积分别为(0.95±0.16)mm、(19.34±1.47)mm^(2),均低于对照组[(1.24±0.18)mm、(20.33±1.87)mm^(2)];管腔直径[(6.47±0.48)mm]大于对照组[(5.53±0.43)mm],P<0.05。治疗后,观察组患者的头晕、头刺痛、肢体麻木、口唇紫暗中医症候积分分别为(1.02±0.56)、(2.02±1.48)、(2.34±0.47)、(2.26±1.22)分,均低于对照组[(2.34±0.43)、(3.20±1.03)、(3.33±1.87)、(3.51±1.49)分],P<0.05。治疗后,观察组全血黏度低切、中切、高切及血浆黏度均低于对照组(P<0.05)。2组不良反应发生率比较差异无统计学意义(P>0.05)。结论溶栓胶囊联合阿司匹林肠溶片治疗颈动脉硬化斑块能提高临床疗效,改善斑块情况,降低中医证候积分,改善血流变指标,且无明显不良反应发生,安全性较高。展开更多
Objective: To study the changes of tissue-type plasminogen activator (t-PA), urokinase-type plasminogen activator (u-PA) expressions and fibrinolysis molecular markers in patients with gastrointestinal cancer in order...Objective: To study the changes of tissue-type plasminogen activator (t-PA), urokinase-type plasminogen activator (u-PA) expressions and fibrinolysis molecular markers in patients with gastrointestinal cancer in order to elucidate their clinical significance. Methods: The plasma levels of t-PA, u-PA, urokinase-type plasminogen activator receptor (u-PAR) and plasmin anti-plasmin complex (PAP) were measured by ELISA. t-PA and u-PA mRNAs were detected by Real-time RT-PCR. Results: The plasma levels of u-PA, u-PAR and PAP were elevated in gastrointestinal cancer patients, while u-PA was markedly elevated in patients with local infiltration, lymph node involvement or distal metastasis. U-PA mRNA was higher and t-PA was lower in gastrointestinal cancer compared to normal tissue. Conclusion: Hyperfibrinolysis is an important factor related with metastasis potential of gastrointestinal cancer. t-PA may be a character of well differentiated tissue.展开更多
基金This work was supported in part by National Institutes of Health Grant NS-NS091201(to MY)and VA MERIT Award IO1BX003441(to MY).
文摘Dementia is a clinical syndrome that affects approximately 47 million people worldwide and is characterized by progressive and irreversible decline of cognitive,behavioral and sesorimotor functions.Alzheimer’s disease(AD)accounts for approximately 60–80%of all cases of dementia,and neuropathologically is characterized by extracellular deposits of insoluble amyloid-β(Aβ)and intracellular aggregates of hyperphosphorylated tau.Significantly,although for a long time it was believed that the extracellular accumulation of Aβwas the culprit of the symptoms observed in these patients,more recent studies have shown that cognitive decline in people suffering this disease is associated with soluble Aβ-induced synaptic dysfunction instead of the formation of insoluble Aβ-containing extracellular plaques.These observations are translationally relevant because soluble Aβ-induced synaptic dysfunction is an early event in AD that precedes neuronal death,and thus is amenable to therapeutic interventions to prevent cognitive decline before the progression to irreversible brain damage.The plasminogen activating(PA)system is an enzymatic cascade that triggers the degradation of fibrin by catalyzing the conversion of plasminogen into plasmin via two serine proteinases:tissue-type plasminogen activator(tPA)and urokinase-type plasminogen activator(uPA).Experimental evidence reported over the last three decades has shown that tPA and uPA play a role in the pathogenesis of AD.However,these studies have focused on the ability of these plasminogen activators to trigger plasmin-induced cleavage of insoluble Aβ-containing extracellular plaques.In contrast,recent evidence indicates that activity-dependent release of uPA from the presynaptic terminal of cerebral cortical neurons protects the synapse from the deleterious effects of soluble Aβvia a mechanism that does not require plasmin generation or the cleavage of Aβfibrils.Below we discuss the role of the PA system in the pathogenesis of AD and the translational relevance of data published to this date.
基金supported in part by National Institutes of Health Grants NS-079331(to MY)and NS-091201(to MY)
文摘Membrane depolarization induces the release of the serine proteinase tissue-type plasminogen activator（t PA） from the presynaptic terminal of cerebral cortical neurons.Once in the synaptic cleft this t PA promotes the exocytosis and subsequent endocytic retrieval of glutamate-containing synaptic vesicles,and regulates the postsynaptic response to the presynaptic release of glutamate.Indeed,t PA has a bidirectional effect on the composition of the postsynaptic density（PSD） that does not require plasmin generation or the presynaptic release of glutamate,but varies according to the baseline level of neuronal activity.Hence,in inactive neurons t PA induces phosphorylation and accumulation in the PSD of the Ca^（2＋）/calmodulin-dependent protein kinase IIα（pCa MKIIα）,followed by pCa MKIIα-induced phosphorylation and synaptic recruitment of Glu R1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid（AMPA） receptors.In contrast,in active neurons with increased levels of pCa MKIIα in the PSD t PA induces pCa MKIIα and p Glu R1 dephosphorylation and their subsequent removal from the PSD.These effects require active synaptic N-methyl-D-aspartate（NMDA） receptors and cyclin-dependent kinase 5（Cdk5）-induced phosphorylation of the protein phosphatase 1（PP1） at T320.These data indicate that t PA is a homeostatic regulator of the postsynaptic response of cerebral cortical neurons to the presynaptic release of glutamate via bidirectional regulation of the pCa MKIIα/PP1 switch in the PSD.
文摘Primary focal and segmental glomerulosclerosis(FSGS) may be due to genetic or acquired etiologies and is a common cause of nephrotic syndrome with high morbidity that often leads to end-stage renal failure. The different available therapeutic approaches are unsuccessful, in part due to partially deciphered heterogeneous and complex pathophysiological mechanisms. Moreover, the term FSGS, even in its primary form, comprises a histological description shared by a number of different causes with completely different molecular pathways of disease. This review focuses on the latest developments regarding the pathophysiology of primary acquired FSGS caused by soluble factor urokinase type plasminogen activator receptor, a circulating permeability factor involved in proteinuria and edema formation, and describes recent advances with potential success in therapy.
文摘组织型纤溶酶原激活剂(tissue type plasmin activator,tPA)是美国食品药品监督管理局唯一批准的用于急性缺血性卒中治疗的药物,但由于治疗时间窗狭窄以及会导致严重的出血性转化(hemorrhagic transformation,HT),其临床应用受到限制。本文拟从血脑屏障破坏、神经炎症、氧化应激以及亚硝酸应激等方面对HT发展的机制及近7年来发表在国内外期刊上的小分子化合物对HT保护的研究进展予以综述,为缺血性中风的新药开发和药物联用提供一定参考。
文摘Aberrant expression of annexin A2-SI00A10 heterotetramer （AIIt） associated with PML/RARα fusion protein causes lethal hyperfibrinolysis in acute promyelocytic leukemia （APL）, but the mechanism is unclear. To facilitate the investigation of regulatory association between ANXA2 and promyelocytic leukemia/retinoic acid receptor α （PML/RARα） fusion protein, this work was performed to determine the transcription start site of ANXA2 promoter with rapid amplification of 5＇-cDNA ends analysis. Zinc-induced U937/PR9 cells expressed PML/RARα fusion protein, and resultant increases in ANXA2 transcripts and translational expressions of both ANXA2 and S100A10, while S100A10 transcripts remained constitutive. The transactivation of ANXA2 promoter by PML/RARα fusion protein was 3.29 ± 0.13 fold higher than that by control pSG5 vector or wild-type RARer. The overexpression of ANXA2 in U937 transfected with full-length ANXA2 cDNA was associated with increased S100A10 subunit, although S100A10 transcripts remained constitutive. The tPA-dependent initial rate of plasmin generation （IRPG） in zinc-treated U937/PR9 increased by 2.13-fold, and cell invasiveness increased by 27.6%. Antibodies against ANXA2, S100A10, or combination of both all remarkably inhibited the IRPG and invasiveness in U937/PR9 and NB4. Treatment of zinc-induced U937/PR9 or circulating APL blasts with all-trans retinoic acid （ATRA） significantly reduced cell surface ANXA2 and S100A10 and associated reductions in IRPG and invasiveness. Thus, PML/RARα fusion protein transactivated the ANXA2 promoter to upregulate ANXA2 and accumulate S100A10. Increased AIIt promoted IRPG and invasiveness, both of which were partly abolished by antibodies against ANXA2 and S100A10 or by ATRA.
文摘目的探讨溶栓胶囊联合阿司匹林治疗颈动脉硬化斑块的疗效。方法选取100例颈动脉粥样硬化斑块患者作为研究对象,用随机数字表法分为观察组(55例,用溶栓胶囊联合阿司匹林肠溶片治疗)和对照组(45例,用阿司匹林肠溶片治疗)。观察2组治疗后的临床疗效、斑块情况、中医症状积分、血流变指标和不良反应发生情况。结果治疗后,观察组的临床总有效率(96.36%)高于对照组(80.00%),P<0.05。观察组患者的内-中膜的厚度(intima media thickness,IMT)和斑块面积分别为(0.95±0.16)mm、(19.34±1.47)mm^(2),均低于对照组[(1.24±0.18)mm、(20.33±1.87)mm^(2)];管腔直径[(6.47±0.48)mm]大于对照组[(5.53±0.43)mm],P<0.05。治疗后,观察组患者的头晕、头刺痛、肢体麻木、口唇紫暗中医症候积分分别为(1.02±0.56)、(2.02±1.48)、(2.34±0.47)、(2.26±1.22)分,均低于对照组[(2.34±0.43)、(3.20±1.03)、(3.33±1.87)、(3.51±1.49)分],P<0.05。治疗后,观察组全血黏度低切、中切、高切及血浆黏度均低于对照组(P<0.05)。2组不良反应发生率比较差异无统计学意义(P>0.05)。结论溶栓胶囊联合阿司匹林肠溶片治疗颈动脉硬化斑块能提高临床疗效,改善斑块情况,降低中医证候积分,改善血流变指标,且无明显不良反应发生,安全性较高。
文摘Objective: To study the changes of tissue-type plasminogen activator (t-PA), urokinase-type plasminogen activator (u-PA) expressions and fibrinolysis molecular markers in patients with gastrointestinal cancer in order to elucidate their clinical significance. Methods: The plasma levels of t-PA, u-PA, urokinase-type plasminogen activator receptor (u-PAR) and plasmin anti-plasmin complex (PAP) were measured by ELISA. t-PA and u-PA mRNAs were detected by Real-time RT-PCR. Results: The plasma levels of u-PA, u-PAR and PAP were elevated in gastrointestinal cancer patients, while u-PA was markedly elevated in patients with local infiltration, lymph node involvement or distal metastasis. U-PA mRNA was higher and t-PA was lower in gastrointestinal cancer compared to normal tissue. Conclusion: Hyperfibrinolysis is an important factor related with metastasis potential of gastrointestinal cancer. t-PA may be a character of well differentiated tissue.
