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
BACKGROUND:Urokinase-type plasminogen activator(uPA) and urokinase-type plasminogen activator receptor(uPAR) are known as important factors,which mediate a variety of functions in terms of vascular homeostasis,inflamm...BACKGROUND:Urokinase-type plasminogen activator(uPA) and urokinase-type plasminogen activator receptor(uPAR) are known as important factors,which mediate a variety of functions in terms of vascular homeostasis,inflammation and tissue repair.However,their role in systemic inflammatory response syndrome(SIRS) has been less well studied.This study aimed to test the hypothesis that the abnormalities of fibrinolysis and degradation of extracellular matrix mediated by uPA and uPAR are directly related to the patients with SIRS.We therefore analyzed their role and clinicopathological significance in patients with SIRS.METHODS:A case-control study was conducted with 85 patients who were divided into two groups according to the diagnostic criteria of SIRS:SIRS group(n=50) and non-SIRS group(/7=35).The SIRS group was divided into MODS group(n=26) and non-MODS group(n=24) by their severity,and survival group(n=35) and non-survival group(n=15) by their prognosis.Another 30 healthy adults served as normal controls.uPA and uPAR in plasma were detected by commercial enzyme-linked immunosorbent assay(ELISA) kits.RESULTS:The plasma level of uPA was lower in the SIRS group than in the non-SIRS group and controls(P<0.001 and P<0.001).It was lower in sepsis patients and the MODS group than in the non-sepsis patients and the non-MODS patients(all P<0.05).However,there was no difference in uPA level between survivors and non-survivors(P>0.05).The plasma level of uPAR increased in the SIRS group compared with the non-SIRS group and controls(P<0.001 and P<0.001).There was a significant elevation of uPAR in sepsis patients,MODS patients and non-survivors as compared with non-sepsis patients,non-MODS patients and survivors respectively(all P<0.05).Plasma uPAR levels were positively correlated with APACHE Ⅱ score(r=0.575,P<0.001) and SOFA score(r=0.349,P=0.013).AUCs for the prediction of SIRS mortality were 0.67 and 0.51,respectively,for uPA and uPAR.CONCLUSION:uPAR could be a predictor of poor outcome in patients with SIRS.展开更多
AIM: To evaluate the therapeutic effects of bone marrow-derived mesenchymal stem cells(BMSCs) with human urokinase-type plasminogen activator(u PA) on liver fibrosis, and to investigate the mechanism of gene therapy.M...AIM: To evaluate the therapeutic effects of bone marrow-derived mesenchymal stem cells(BMSCs) with human urokinase-type plasminogen activator(u PA) on liver fibrosis, and to investigate the mechanism of gene therapy.METHODS: BMSCs transfected with adenovirusmediated human urokinase plasminogen activator(Adu PA) were transplanted into rats with CCl4-induced liver fibrosis. All rats were sacrificed after 8 wk, and their serum and liver tissue were collected for biochemical, histopathologic, and molecular analyzes. The degree of liver fibrosis was assessed by hematoxylin and eosin or Masson's staining. Western blot and quantitative reverse transcription-polymerase chain reaction were used to determine protein and m RNA expression levels.RESULTS: Serum levels of alanine aminotransferase, aminotransferase, total bilirubin, hyaluronic acid, laminin, and procollagen type Ⅲ were markedly decreased, whereas the levels of serum albumin were increased by u PA gene modified BMSCs treatment. Histopathology revealed that chronic CCl4-treatment resulted in significant fibrosis while u PA gene modified BMSCs treatment significantly reversed fibrosis. By quantitatively analysing the fibrosis area of liver tissue using Masson staining in different groups of animals, we found that model animals with CCl4-induced liver fibrosis had the largest fibrotic area(16.69% ± 1.30%), while fibrotic area was significantly decreased by BMSCs treatment(12.38% ± 2.27%) and was further reduced by u PA-BMSCs treatment(8.31% ± 1.21%). Both protein and m RNA expression of β-catenin, Wnt4 and Wnt5 a was down-regulated in liver tissues following u PA gene modified BMSCs treatment when compared with the model animals.CONCLUSION: Transplantation of u PA gene modified BMSCs suppressed liver fibrosis and ameliorated liver function and may be a new approach to treating liver fibrosis. Furthermore, treatment with u PA gene modified BMSCs also resulted in a decrease in expression of molecules of the Wnt signaling pathway.展开更多
Tissue plasminogen activator is usually used for the treatment of acute ischemic stroke,but the role of endogenous tissue plasminogen activator in traumatic brain injury has been rarely reported.A rat model of traumat...Tissue plasminogen activator is usually used for the treatment of acute ischemic stroke,but the role of endogenous tissue plasminogen activator in traumatic brain injury has been rarely reported.A rat model of traumatic brain injury was established by weight-drop method.The tissue plasminogen activator inhibitor neuroserpin(5μL,0.25 mg/mL)was injected into the lateral ventricle.Neurological function was assessed by neurological severity score.Neuronal and axonal injuries were assessed by hematoxylin-eosin staining and Bielschowsky silver staining.Protein level of endogenous tissue plasminogen activator was analyzed by western blot assay.Apoptotic marker cleaved caspase-3,neuronal marker neurofilament light chain,astrocyte marker glial fibrillary acidic protein and microglial marker Iba-1 were analyzed by immunohistochemical staining.Apoptotic cell types were detected by immunofluorescence double labeling.Apoptotic cells in the damaged cortex were detected by terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP-biotin nick-end labeling staining.Degenerating neurons in the damaged cortex were detected by Fluoro-Jade B staining.Expression of tissue plasminogen activator was increased at 6 hours,and peaked at 3 days after traumatic brain injury.Neuronal apoptosis and axonal injury were detected after traumatic brain injury.Moreover,neuroserpin enhanced neuronal apoptosis,neuronal injury and axonal injury,and activated microglia and astrocytes.Neuroserpin further deteriorated neurobehavioral function in rats with traumatic brain injury.Our findings confirm that inhibition of endogenous tissue plasminogen activator aggravates neuronal apoptosis and axonal injury after traumatic brain injury,and activates microglia and astrocytes.This study was approved by the Biomedical Ethics Committee of Animal Experiments of Shaanxi Province of China in June 2015.展开更多
The last two decades have witnessed a rapid decrease in mortality due to acute cerebral ischemia that paradoxically has led to a rapid increase in the number of patients that survive an acute ischemic stroke with vari...The last two decades have witnessed a rapid decrease in mortality due to acute cerebral ischemia that paradoxically has led to a rapid increase in the number of patients that survive an acute ischemic stroke with various degrees of disability.Unfortunately,the lack of an effective therapeutic strategy to promote neurological recovery among stroke survivors has led to a rapidly growing population of disabled patients.Thus,understanding the mechanisms of neurorepair in the ischemic brain is a priority with wide scientific,social and economic implications.Cerebral ischemia has a harmful effect on synaptic structure associated with the development of functional impairment.In agreement with these observations,experimental evidence indicates that synaptic repair underlies the recovery of neurological function following an ischemic stroke.Furthermore,it has become evident that synaptic plasticity is crucial not only during development and learning,but also for synaptic repair after an ischemic insult.The plasminogen activating system is assembled by a cascade of enzymes and their inhibitors initially thought to be solely involved in the generation of plasmin.However,recent work has shown that in the brain this system has an important function regulating the development of synaptic plasticity via mechanisms that not always require plasmin generation.Urokinase-type plasminogen activator(uPA)is a serine proteinase and one of the plasminogen activators,that upon binding to its receptor(uPAR)not only catalyzes the conversion of plasminogen into plasmin on the cell surface,but also activates cell signaling pathways that promote cell migration,proliferation and survival.The role of uPA is the brain is not fully understood.However,it has been reported while uPA and uPAR are abundantly found in the developing central nervous system,in the mature brain their expression is restricted to a limited group of cells.Remarkably,following an ischemic injury to the mature brain the expression of uPA and uPAR increases to levels comparable to those observed during development.More specifically,neurons release uPA during the recovery phase from an ischemic injury,and astrocytes,axonal boutons and dendritic spines recruit uPAR to their plasma membrane.Here we will review recent evidence indicating that binding of uPA to uPAR promotes the repair of synapses damaged by an ischemic injury,with the resultant recovery of neurological function.Furthermore,we will discuss data indicating that treatment with recombinant uPA is a potential therapeutic strategy to promote neurological recovery among ischemic stroke survivors.展开更多
INTRODUCTIONPlasminogen activator inhibitor type 1 ( PAI-I ), an approximately Mr 50000 glycoprotein, is the major physiological inhibitor of plasminogen activators. It is not only the priming factor for atheroscleros...INTRODUCTIONPlasminogen activator inhibitor type 1 ( PAI-I ), an approximately Mr 50000 glycoprotein, is the major physiological inhibitor of plasminogen activators. It is not only the priming factor for atherosclerosis and coronary thrombosis[1-3] , but also participates in the genesis of chronic hepatitis and liver fibrosis[4-11] . However, there has been no available report yet about the research of hepatic PAl-1 gene expression in hyperlipidemia and fatty liver. The present study aimed to explore the change of hepatic PAl-1 mRNA and its plasma activity by means of animal model.展开更多
To clarify the role of urokinase plasminogen activator(uPA) in the mechanisms of regulating sperm motility and the ability of fertilizing, we investigated the quantities and activities of uPA in human seminal Plasma a...To clarify the role of urokinase plasminogen activator(uPA) in the mechanisms of regulating sperm motility and the ability of fertilizing, we investigated the quantities and activities of uPA in human seminal Plasma and on the membrane of spermatozoa.Semens were harvested from 22 infertile patients with asthenospermia and 20 healthy fertile men according to WHO standards. To quantify the membrane-bound uPA in the samples, polyclonal antibodies against human urokinase were employed by means of a sandwich ELISA. The uPA activities in seminal plasma and on the surface of spermatozoa were determined using Agarose-Fibrine-Plate method and the experiment of immunological identification with polyclonal antibodies against urokinase. In lysates of spermatozoa, significantly lower levels of uPA(23. 1±7.35 mu/106 cells ) and uPA activity (5.13±3.85 mu/106 cells) were found in patient group as compared to healthy fertile men exhibiting normospermia (29. 89±9. 40 mu/105 cells and 10. 17±6. 18 mu/106 cells). In seminal plasma, uPA activity in patient group (2134±1581. 3 IU/L)was also found significantly lower than that of normal group (3365±1859. 5 IU/L). Positive correlations were observed between sperm motility and uPA quantities (r=0. 48, P＜0. 005), as well as with uPA activities (r= 0. 45,P＜0. 005).Thus, it is inferred that membrane associated uPA on human spermatozoa may be related directly to sperm motility and fertility.展开更多
AIM:To investigate the role of tissue plasminogen activator(t-PA) and plasminogen activator inhibitor(PAI)in proliferative diabetic retinopathy(PDR) and to discuss the correlations among t-PA, PAI and vascular endothe...AIM:To investigate the role of tissue plasminogen activator(t-PA) and plasminogen activator inhibitor(PAI)in proliferative diabetic retinopathy(PDR) and to discuss the correlations among t-PA, PAI and vascular endothelial growth factor(VEGF) expressions.METHODS:A total of 36 vitreous samples were collected from 36 patients with PDR(PDR group), and 17 vitreous samples from 17 patients with idiopathic macular hole were used as control. The concentrations of t-PA, PAI and VEGF in samples were determined by ELISA method. The correlations among t-PA, PAI and VEGF expressions were discussed.RESULTS:The concentrations of t-PA, PAI and VEGF in the PDR group were significantly higher than those in the control group(P <0.001). The t-PA and PAI expressions were highly correlated with the VEGF expression(P <0.001).CONCLUSION:In addition to VEGF, a variety of bioactive substances, such as t-PA and PAI, are involved in the pathogenesis involved in the angiogenesis of PDR.VEGF can activate t-PA expression, resulting in collagen tissue degradation and angiogenesis. VEGF may also activate the mechanism for endogenous anti-neovascularization.展开更多
BACKGROUND:The study aimed to compare the therapeutic effect of recombinant tissue plasminogen activator(rt-PA) on the onset of acute cerebral infarction(ACI) at different time points of the first 6 hours.METHODS:A re...BACKGROUND:The study aimed to compare the therapeutic effect of recombinant tissue plasminogen activator(rt-PA) on the onset of acute cerebral infarction(ACI) at different time points of the first 6 hours.METHODS:A retrospective analysis was conducted in 74 patients who received rt-PA thrombolysis treatment within 4.5 hours after ACI and another 15 patients who received rt-PA thrombolysis treatment between 4.5-6 hours after ACI.RESULTS:National Institute of Health Stroke Scale(NIHSS) scores were statistically decreased in both groups(P>0.05) at 24 hours and 7 days after ACI.There was no significant difference in modified ranking scores and mortality at 90 days after the treatment between the two groups(P>0.05).CONCLUSIONS:The therapeutic effect and mortality of rt-PA treatment in patients with ACI between 4.5-6 hours after the onset of the disease were similar to those in patients who received rtPA within 4.5 hours after the onset of this disease.Therefore,intravenous thrombolytic therapy for ACI within 4.5-6 hours after ACI was effective and safe.展开更多
Dear Editor,I am Dr.Zhao PQ,from the Department of Ophthalmology,Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,Shanghai,China.I write to present a case report of tissue plasminogen ac...Dear Editor,I am Dr.Zhao PQ,from the Department of Ophthalmology,Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,Shanghai,China.I write to present a case report of tissue plasminogen activator(tP A)-assisted vitrectomy in the early treatment of acute massive展开更多
AIM To investigate serum urokinase-type plasminogen activator receptor(u PAR) and liver stiffness in biliary atresia(BA) and examine the correlation of circulating u PAR, liver stiffness, and clinical outcomes in post...AIM To investigate serum urokinase-type plasminogen activator receptor(u PAR) and liver stiffness in biliary atresia(BA) and examine the correlation of circulating u PAR, liver stiffness, and clinical outcomes in postoperative BA children.METHODS Eighty-five post Kasai BA children and 24 control subjects were registered. Circulating u PAR was measured using enzyme-linked immunosorbent essay. Liver stiffness was analyzed using transient elastography.RESULTS BA children had significantly greater circulating u PAR andliver stiffness scores than control subjects(P < 0.001). Circulating u PAR and liver stiffness were substantially higher in jaundiced BA children than non-jaundiced BA children(P < 0.001). In addition, circulating u PAR was positively associated with serum aspartate aminotransferase(r = 0.507, P < 0.001), alanine aminotransferase(r = 0.364, P < 0.001), total bilirubin(r = 0.559, P < 0.001), alkaline phosphatase(r = 0.325, P < 0.001), and liver stiffness scores(r = 0.508, P < 0.001).CONCLUSION Circulating u PAR and liver stiffness values were greater in BA children than healthy controls. The increased circulating u PAR was associated with liver dysfunction in BA. As a consequence, serum u PAR and liver stiffness may be used as noninvasive biomarkers indicating the progression of liver fibrosis in post Kasai BA.展开更多
Background: PAI-1 (plasminogen activator inhibitor-1) is a powerful regulator of fibrinolysis and plasma level is high in type 2 diabetes and cardio-vascular disease, which is determined by genetic polymorphisms in PA...Background: PAI-1 (plasminogen activator inhibitor-1) is a powerful regulator of fibrinolysis and plasma level is high in type 2 diabetes and cardio-vascular disease, which is determined by genetic polymorphisms in PAI-1 gene and environmental factors. The aim of the study was to examine the determinants of plasma PAI-1 Ag level among type 2 diabetes patients. Methods: 491 Tunisian type 2 diabetes patients had clinical evaluation (weight, high, BMI, Waist Circumference), laboratory investigations including FBG Hb1Ac, cholesterol, triglyceride;HDL-cholesterol was done;plasma PAI-1 antigen level was done with ELISA;−675 4G/5G and −844 G/A polymorphisms of PAI-1 gene was done by PCR-ASA and PCR-RFLP respectively. Results: The mean age for our patients was 58.3 ± 10.5 years;sex-ratio = 0.92;mean PAI-1 level was 34.6 ± 21.3 ng/ml. We didn’t find correlation between PAI-1 level and BMI, but we have found significant correlation between PAI-1 and waist circumference (p = 0.032), most enhanced in men (P = 0.002), T2D patients who have FBG > 11 mmol/l had PAI-1 Ag level higher than those who have FBG P = 0.034), but no difference found between T2D with high Hb1Ac > 8% and those with Hb1Ac < 8%, significant correlation was seen between PAI-1 level and LDL-cholesterol (P = 0.05), high correlation between PAI-1 Ag level and −675 4G/5G polymorphism genotype was seen, 4G/4G carriers had the highest PAI-1 level, 4G/5G had intermediary level and 5G/5G had the lowest level (P −844G/A polymorphism genotypes. Using multiple variable linear regression analysis, the independent factor associated with plasma PAI-1 level was −675 4G/5G polymorphism (regression coefficient β = 4.6, P Conclusion: the present study identifies −675 4G/5G not −844 G/A polymorphism of PAI gene as the principal determinant of plasma PAI-1 level in Tunisian T2D patients, the android fat distribution, dyslipidemia and hyperglycemia play a modest role in this variation.展开更多
Tissue plasminogen activator(t PA)use in the treatment of ischemic stroke:t PA is a serine protease that catalyzes the breakdown of blood clots.Because of its thrombolytic properties,t PA is used to treat specific typ...Tissue plasminogen activator(t PA)use in the treatment of ischemic stroke:t PA is a serine protease that catalyzes the breakdown of blood clots.Because of its thrombolytic properties,t PA is used to treat specific types of stroke,including ischemia,but is contraindicated for treatment of hemorrhagic stroke or head trauma.Although a life saving and powerful‘clot buster’,t PA has a展开更多
Objective: To study the expression and clinicalsignificance of urokinase-type plasminogen activator(uPA) in breast cancer. Methods: Applyingstreptavidin-biotin complex (SABC) immunohistochemical technique, expression ...Objective: To study the expression and clinicalsignificance of urokinase-type plasminogen activator(uPA) in breast cancer. Methods: Applyingstreptavidin-biotin complex (SABC) immunohistochemical technique, expression of uPA was studied in100 patients with primary breast canceL Results: Therewere 55 patients with high uPA expression, and 45 withlower expression. There was significant correlationbetween uPA expression and TNM stage, lymph nodestatus, and the tumor size. Neither age, menopausalstatus, nor ER status was significantly related with levelof uPA expression. The patients with high expression ofuPA had significantly shorter disease-free survival (DFS)and overall survival (OS) than did those with lowexpression of uPA. Univariate analysis showed that uPAas a prognostic factor was of similar magnitude tolymph node status and TNM stage, hut stronger thanthat of ER status and tumor size. UPA was anindependent prognostic factor affecting disease-freesurvival and overall survival. Collclusion: uPA appearsto be a strong and independent biologic marker forpredicting prognosis of breast cancer.展开更多
In order to further investigate the effect of annexinⅡ(Ann Ⅱ) on tissue plasminogen activator (t PA) dependent plasminogen (PLG) activation and its interactive mechanism, recombinant native Ann Ⅱ bound t PA, PLG an...In order to further investigate the effect of annexinⅡ(Ann Ⅱ) on tissue plasminogen activator (t PA) dependent plasminogen (PLG) activation and its interactive mechanism, recombinant native Ann Ⅱ bound t PA, PLG and plasmin with high affinity was examined. The flow cytometric assay showed that the ann Ⅱexpression rate was higher in the human umbilical vein endothelial cell (HUVEC) (87 65 %) than in the HL 60 cells as controls (35.79 %). Two irrelevant proteins, bovine serum albumin (BSA) and equine IgG (EIG) had no effect on the production of plasmin. Ann Ⅱ mediated enhancement of t PA dependent PLG activation was inhibited by ε aminocaproic acid or by pretreatment of Ann Ⅱ with carboxypeptidase B with the inhibitive rate being 77.8 % and 77.0 %, respectively. It was revealed that the effect of Ann Ⅱon PLG activation was specific for t PA. Urokinase didn’t bind to Ann Ⅱ, demonstrating the role of receptor related lysine residues on activation of PLG, showing that the Ann Ⅱ PLG interaction was dependent upon carboxyl terminal lysine residues. These findings suggest that annexin Ⅱ mediated co assembly of t PA and PLG may promote plasmin generation and play a key role in modulating fibrinolysis on the endothelial surface.展开更多
OBJECTIVE To investigate the thrombolytic and antiplatelet effects of a novel plasminogen activator from the venom of Gloydius brevicaudus viper(GBV-PA)in vitro and in vivo.METHODS Thrombolytic experiments were perfor...OBJECTIVE To investigate the thrombolytic and antiplatelet effects of a novel plasminogen activator from the venom of Gloydius brevicaudus viper(GBV-PA)in vitro and in vivo.METHODS Thrombolytic experiments were performed in rabbit models of ear vein thrombosis and carotid artery thrombosis,and in dog model of acute cerebral infarction.Inhibition of thrombus formation was evaluated in rat inferior vena cava thrombosis model and ferric chloride-induced arterial thrombosis.In vitro,we assayed the antithrombotic effect of GBV-PA on rabbit blood clots,euglobulin lysis time(ELT)of rabbit plasma,and on ADP-induced platelet aggregation.RESULTS GBV-PA intravenous administ ration significantly reduced vascular recanalization times of rabbit ear veins thrombosis and thrombus weight of rabbit carotid artery thrombosis.The arterial recanalization rates were dose-and time-dependently improved after administration of GBV-PA in canine acute cerebral infarction model.Thrombus length and weight was significantly reduced by GBV-PA both in rat inferior vena cava and ferric chloride-induced arterial thrombosis models.Thrombus formation of blood of rabbits they were administrated with GBV-PA was also inhibited.GBV-PA radically reduced plasma ELT of rabbit′s blood clots.ADP-induced platelet aggregation was inhibited by GBV-PA in a dose-dependent manner with a half-maximal inhibitory concentration of 19.9μg·mL-1.CONCLUSION This study demonstrates that GBV-PA is a thrombolytic and antiplatelet agent.It has significant antithrombotic effects on various in vitro and in vivo experimental models of thrombosis.The mechanisms that underline its antithrombotic effects were related to GBV-PA′s capabilities of increasing fibrinolytic activities and inhibition of platelet aggregation.展开更多
Objective To observe the changes of the activity of tissue -type plasminogen activa tor(TPA)after asphyxia.Methods As-phyxia was induced in mouse pups by performing a ‘delayed cesarean section’.The experiment was de...Objective To observe the changes of the activity of tissue -type plasminogen activa tor(TPA)after asphyxia.Methods As-phyxia was induced in mouse pups by performing a ‘delayed cesarean section’.The experiment was designed for a co ntrol group and 4asphyctic groups to detect the activity of TPA.Results TPAactivity of brain increased afte r asphyxia(P <0.01).Conclusion TPAincreased after asphyxia might be able to attack the b asement membrane of microvessels,t hen opened the blood -brain barrier a nd induced neuronal damage.展开更多
Tandem internal carotid and middle cerebral artery occlusion after carotid dissection predicts poor outcome after systemic thrombolysis. Current treatments include the use of endovascular carotid stenting, which carri...Tandem internal carotid and middle cerebral artery occlusion after carotid dissection predicts poor outcome after systemic thrombolysis. Current treatments include the use of endovascular carotid stenting, which carries with it a high risk of propagating further embolic events and worsening the dissection. New strategies for avoiding the aforementioned side-effects include recanalization using cross-collaterals for delivery of intra-lesional tissue plasminogen activator(t PA). We present two cases that provide further support for this novel approach. Both patients presented with a National Institute of Health Stroke Scale of 20, received intra-arterial t PA via cross-collateralization, and made full recoveries without the need for stenting.展开更多
Dear Sir,We congratulate Wu et al[1] for their study entitled'Roles of tissue plasminogen activator and its inhibitor in proliferative diabetic retinopathy'.The authors investigated the effects of tissue plasm...Dear Sir,We congratulate Wu et al[1] for their study entitled'Roles of tissue plasminogen activator and its inhibitor in proliferative diabetic retinopathy'.The authors investigated the effects of tissue plasminogen activator（t-PA）and plasminogen activator inhibitor（PAI）in the pathogenesis of proliferative diabetic retinopathy（PDR）.The authors reported that t-PA and PAI are involved in the pathogenesis of PDR.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.
文摘BACKGROUND:Urokinase-type plasminogen activator(uPA) and urokinase-type plasminogen activator receptor(uPAR) are known as important factors,which mediate a variety of functions in terms of vascular homeostasis,inflammation and tissue repair.However,their role in systemic inflammatory response syndrome(SIRS) has been less well studied.This study aimed to test the hypothesis that the abnormalities of fibrinolysis and degradation of extracellular matrix mediated by uPA and uPAR are directly related to the patients with SIRS.We therefore analyzed their role and clinicopathological significance in patients with SIRS.METHODS:A case-control study was conducted with 85 patients who were divided into two groups according to the diagnostic criteria of SIRS:SIRS group(n=50) and non-SIRS group(/7=35).The SIRS group was divided into MODS group(n=26) and non-MODS group(n=24) by their severity,and survival group(n=35) and non-survival group(n=15) by their prognosis.Another 30 healthy adults served as normal controls.uPA and uPAR in plasma were detected by commercial enzyme-linked immunosorbent assay(ELISA) kits.RESULTS:The plasma level of uPA was lower in the SIRS group than in the non-SIRS group and controls(P<0.001 and P<0.001).It was lower in sepsis patients and the MODS group than in the non-sepsis patients and the non-MODS patients(all P<0.05).However,there was no difference in uPA level between survivors and non-survivors(P>0.05).The plasma level of uPAR increased in the SIRS group compared with the non-SIRS group and controls(P<0.001 and P<0.001).There was a significant elevation of uPAR in sepsis patients,MODS patients and non-survivors as compared with non-sepsis patients,non-MODS patients and survivors respectively(all P<0.05).Plasma uPAR levels were positively correlated with APACHE Ⅱ score(r=0.575,P<0.001) and SOFA score(r=0.349,P=0.013).AUCs for the prediction of SIRS mortality were 0.67 and 0.51,respectively,for uPA and uPAR.CONCLUSION:uPAR could be a predictor of poor outcome in patients with SIRS.
基金Supported by National Natural Science Foundation of ChinaNo.81460114+5 种基金Natural Science Foundation of Guangxi Zhuang Autonomous RegionNo.1355005-3-2 and No.2012GXNSFAA053143Chinese Traditional Medicine Science Foundation of Guangxi Zhuang Autonomous RegionNo.GZPT1238Science Foundation of Guangxi Department of EducationNo.201203YB036 and No.2013LX031
文摘AIM: To evaluate the therapeutic effects of bone marrow-derived mesenchymal stem cells(BMSCs) with human urokinase-type plasminogen activator(u PA) on liver fibrosis, and to investigate the mechanism of gene therapy.METHODS: BMSCs transfected with adenovirusmediated human urokinase plasminogen activator(Adu PA) were transplanted into rats with CCl4-induced liver fibrosis. All rats were sacrificed after 8 wk, and their serum and liver tissue were collected for biochemical, histopathologic, and molecular analyzes. The degree of liver fibrosis was assessed by hematoxylin and eosin or Masson's staining. Western blot and quantitative reverse transcription-polymerase chain reaction were used to determine protein and m RNA expression levels.RESULTS: Serum levels of alanine aminotransferase, aminotransferase, total bilirubin, hyaluronic acid, laminin, and procollagen type Ⅲ were markedly decreased, whereas the levels of serum albumin were increased by u PA gene modified BMSCs treatment. Histopathology revealed that chronic CCl4-treatment resulted in significant fibrosis while u PA gene modified BMSCs treatment significantly reversed fibrosis. By quantitatively analysing the fibrosis area of liver tissue using Masson staining in different groups of animals, we found that model animals with CCl4-induced liver fibrosis had the largest fibrotic area(16.69% ± 1.30%), while fibrotic area was significantly decreased by BMSCs treatment(12.38% ± 2.27%) and was further reduced by u PA-BMSCs treatment(8.31% ± 1.21%). Both protein and m RNA expression of β-catenin, Wnt4 and Wnt5 a was down-regulated in liver tissues following u PA gene modified BMSCs treatment when compared with the model animals.CONCLUSION: Transplantation of u PA gene modified BMSCs suppressed liver fibrosis and ameliorated liver function and may be a new approach to treating liver fibrosis. Furthermore, treatment with u PA gene modified BMSCs also resulted in a decrease in expression of molecules of the Wnt signaling pathway.
文摘Tissue plasminogen activator is usually used for the treatment of acute ischemic stroke,but the role of endogenous tissue plasminogen activator in traumatic brain injury has been rarely reported.A rat model of traumatic brain injury was established by weight-drop method.The tissue plasminogen activator inhibitor neuroserpin(5μL,0.25 mg/mL)was injected into the lateral ventricle.Neurological function was assessed by neurological severity score.Neuronal and axonal injuries were assessed by hematoxylin-eosin staining and Bielschowsky silver staining.Protein level of endogenous tissue plasminogen activator was analyzed by western blot assay.Apoptotic marker cleaved caspase-3,neuronal marker neurofilament light chain,astrocyte marker glial fibrillary acidic protein and microglial marker Iba-1 were analyzed by immunohistochemical staining.Apoptotic cell types were detected by immunofluorescence double labeling.Apoptotic cells in the damaged cortex were detected by terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP-biotin nick-end labeling staining.Degenerating neurons in the damaged cortex were detected by Fluoro-Jade B staining.Expression of tissue plasminogen activator was increased at 6 hours,and peaked at 3 days after traumatic brain injury.Neuronal apoptosis and axonal injury were detected after traumatic brain injury.Moreover,neuroserpin enhanced neuronal apoptosis,neuronal injury and axonal injury,and activated microglia and astrocytes.Neuroserpin further deteriorated neurobehavioral function in rats with traumatic brain injury.Our findings confirm that inhibition of endogenous tissue plasminogen activator aggravates neuronal apoptosis and axonal injury after traumatic brain injury,and activates microglia and astrocytes.This study was approved by the Biomedical Ethics Committee of Animal Experiments of Shaanxi Province of China in June 2015.
基金supported in part by National Institutes of Health Grant NS-091201(to MY)VA MERIT Award IO1BX003441(to MY)
文摘The last two decades have witnessed a rapid decrease in mortality due to acute cerebral ischemia that paradoxically has led to a rapid increase in the number of patients that survive an acute ischemic stroke with various degrees of disability.Unfortunately,the lack of an effective therapeutic strategy to promote neurological recovery among stroke survivors has led to a rapidly growing population of disabled patients.Thus,understanding the mechanisms of neurorepair in the ischemic brain is a priority with wide scientific,social and economic implications.Cerebral ischemia has a harmful effect on synaptic structure associated with the development of functional impairment.In agreement with these observations,experimental evidence indicates that synaptic repair underlies the recovery of neurological function following an ischemic stroke.Furthermore,it has become evident that synaptic plasticity is crucial not only during development and learning,but also for synaptic repair after an ischemic insult.The plasminogen activating system is assembled by a cascade of enzymes and their inhibitors initially thought to be solely involved in the generation of plasmin.However,recent work has shown that in the brain this system has an important function regulating the development of synaptic plasticity via mechanisms that not always require plasmin generation.Urokinase-type plasminogen activator(uPA)is a serine proteinase and one of the plasminogen activators,that upon binding to its receptor(uPAR)not only catalyzes the conversion of plasminogen into plasmin on the cell surface,but also activates cell signaling pathways that promote cell migration,proliferation and survival.The role of uPA is the brain is not fully understood.However,it has been reported while uPA and uPAR are abundantly found in the developing central nervous system,in the mature brain their expression is restricted to a limited group of cells.Remarkably,following an ischemic injury to the mature brain the expression of uPA and uPAR increases to levels comparable to those observed during development.More specifically,neurons release uPA during the recovery phase from an ischemic injury,and astrocytes,axonal boutons and dendritic spines recruit uPAR to their plasma membrane.Here we will review recent evidence indicating that binding of uPA to uPAR promotes the repair of synapses damaged by an ischemic injury,with the resultant recovery of neurological function.Furthermore,we will discuss data indicating that treatment with recombinant uPA is a potential therapeutic strategy to promote neurological recovery among ischemic stroke survivors.
文摘INTRODUCTIONPlasminogen activator inhibitor type 1 ( PAI-I ), an approximately Mr 50000 glycoprotein, is the major physiological inhibitor of plasminogen activators. It is not only the priming factor for atherosclerosis and coronary thrombosis[1-3] , but also participates in the genesis of chronic hepatitis and liver fibrosis[4-11] . However, there has been no available report yet about the research of hepatic PAl-1 gene expression in hyperlipidemia and fatty liver. The present study aimed to explore the change of hepatic PAl-1 mRNA and its plasma activity by means of animal model.
文摘To clarify the role of urokinase plasminogen activator(uPA) in the mechanisms of regulating sperm motility and the ability of fertilizing, we investigated the quantities and activities of uPA in human seminal Plasma and on the membrane of spermatozoa.Semens were harvested from 22 infertile patients with asthenospermia and 20 healthy fertile men according to WHO standards. To quantify the membrane-bound uPA in the samples, polyclonal antibodies against human urokinase were employed by means of a sandwich ELISA. The uPA activities in seminal plasma and on the surface of spermatozoa were determined using Agarose-Fibrine-Plate method and the experiment of immunological identification with polyclonal antibodies against urokinase. In lysates of spermatozoa, significantly lower levels of uPA(23. 1±7.35 mu/106 cells ) and uPA activity (5.13±3.85 mu/106 cells) were found in patient group as compared to healthy fertile men exhibiting normospermia (29. 89±9. 40 mu/105 cells and 10. 17±6. 18 mu/106 cells). In seminal plasma, uPA activity in patient group (2134±1581. 3 IU/L)was also found significantly lower than that of normal group (3365±1859. 5 IU/L). Positive correlations were observed between sperm motility and uPA quantities (r=0. 48, P＜0. 005), as well as with uPA activities (r= 0. 45,P＜0. 005).Thus, it is inferred that membrane associated uPA on human spermatozoa may be related directly to sperm motility and fertility.
基金Supported by Natural Science Foundation of Ningxia(No.NZ10129)
文摘AIM:To investigate the role of tissue plasminogen activator(t-PA) and plasminogen activator inhibitor(PAI)in proliferative diabetic retinopathy(PDR) and to discuss the correlations among t-PA, PAI and vascular endothelial growth factor(VEGF) expressions.METHODS:A total of 36 vitreous samples were collected from 36 patients with PDR(PDR group), and 17 vitreous samples from 17 patients with idiopathic macular hole were used as control. The concentrations of t-PA, PAI and VEGF in samples were determined by ELISA method. The correlations among t-PA, PAI and VEGF expressions were discussed.RESULTS:The concentrations of t-PA, PAI and VEGF in the PDR group were significantly higher than those in the control group(P <0.001). The t-PA and PAI expressions were highly correlated with the VEGF expression(P <0.001).CONCLUSION:In addition to VEGF, a variety of bioactive substances, such as t-PA and PAI, are involved in the pathogenesis involved in the angiogenesis of PDR.VEGF can activate t-PA expression, resulting in collagen tissue degradation and angiogenesis. VEGF may also activate the mechanism for endogenous anti-neovascularization.
基金supported by a grant from Shanghai Municipal Health Bureau(GWDTR201219)
文摘BACKGROUND:The study aimed to compare the therapeutic effect of recombinant tissue plasminogen activator(rt-PA) on the onset of acute cerebral infarction(ACI) at different time points of the first 6 hours.METHODS:A retrospective analysis was conducted in 74 patients who received rt-PA thrombolysis treatment within 4.5 hours after ACI and another 15 patients who received rt-PA thrombolysis treatment between 4.5-6 hours after ACI.RESULTS:National Institute of Health Stroke Scale(NIHSS) scores were statistically decreased in both groups(P>0.05) at 24 hours and 7 days after ACI.There was no significant difference in modified ranking scores and mortality at 90 days after the treatment between the two groups(P>0.05).CONCLUSIONS:The therapeutic effect and mortality of rt-PA treatment in patients with ACI between 4.5-6 hours after the onset of the disease were similar to those in patients who received rtPA within 4.5 hours after the onset of this disease.Therefore,intravenous thrombolytic therapy for ACI within 4.5-6 hours after ACI was effective and safe.
基金Supported by the National Natural Science Foundation of China(No.81500725No.81770963+1 种基金No.81470642)Shanghai Science and Technology Committee(No.15XD1502800)
文摘Dear Editor,I am Dr.Zhao PQ,from the Department of Ophthalmology,Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,Shanghai,China.I write to present a case report of tissue plasminogen activator(tP A)-assisted vitrectomy in the early treatment of acute massive
基金the Thailand Research Fund (RSA5880019)the Research Chair Grant from the National Science and Technology Development Agency+2 种基金the 100th Anniversary Chulalongkorn University Fund for Doctoral Scholarship to WUNational Research University Project, through the Ageing Cluster (NRU59056-AS)Chulalongkorn University
文摘AIM To investigate serum urokinase-type plasminogen activator receptor(u PAR) and liver stiffness in biliary atresia(BA) and examine the correlation of circulating u PAR, liver stiffness, and clinical outcomes in postoperative BA children.METHODS Eighty-five post Kasai BA children and 24 control subjects were registered. Circulating u PAR was measured using enzyme-linked immunosorbent essay. Liver stiffness was analyzed using transient elastography.RESULTS BA children had significantly greater circulating u PAR andliver stiffness scores than control subjects(P < 0.001). Circulating u PAR and liver stiffness were substantially higher in jaundiced BA children than non-jaundiced BA children(P < 0.001). In addition, circulating u PAR was positively associated with serum aspartate aminotransferase(r = 0.507, P < 0.001), alanine aminotransferase(r = 0.364, P < 0.001), total bilirubin(r = 0.559, P < 0.001), alkaline phosphatase(r = 0.325, P < 0.001), and liver stiffness scores(r = 0.508, P < 0.001).CONCLUSION Circulating u PAR and liver stiffness values were greater in BA children than healthy controls. The increased circulating u PAR was associated with liver dysfunction in BA. As a consequence, serum u PAR and liver stiffness may be used as noninvasive biomarkers indicating the progression of liver fibrosis in post Kasai BA.
文摘Background: PAI-1 (plasminogen activator inhibitor-1) is a powerful regulator of fibrinolysis and plasma level is high in type 2 diabetes and cardio-vascular disease, which is determined by genetic polymorphisms in PAI-1 gene and environmental factors. The aim of the study was to examine the determinants of plasma PAI-1 Ag level among type 2 diabetes patients. Methods: 491 Tunisian type 2 diabetes patients had clinical evaluation (weight, high, BMI, Waist Circumference), laboratory investigations including FBG Hb1Ac, cholesterol, triglyceride;HDL-cholesterol was done;plasma PAI-1 antigen level was done with ELISA;−675 4G/5G and −844 G/A polymorphisms of PAI-1 gene was done by PCR-ASA and PCR-RFLP respectively. Results: The mean age for our patients was 58.3 ± 10.5 years;sex-ratio = 0.92;mean PAI-1 level was 34.6 ± 21.3 ng/ml. We didn’t find correlation between PAI-1 level and BMI, but we have found significant correlation between PAI-1 and waist circumference (p = 0.032), most enhanced in men (P = 0.002), T2D patients who have FBG > 11 mmol/l had PAI-1 Ag level higher than those who have FBG P = 0.034), but no difference found between T2D with high Hb1Ac > 8% and those with Hb1Ac < 8%, significant correlation was seen between PAI-1 level and LDL-cholesterol (P = 0.05), high correlation between PAI-1 Ag level and −675 4G/5G polymorphism genotype was seen, 4G/4G carriers had the highest PAI-1 level, 4G/5G had intermediary level and 5G/5G had the lowest level (P −844G/A polymorphism genotypes. Using multiple variable linear regression analysis, the independent factor associated with plasma PAI-1 level was −675 4G/5G polymorphism (regression coefficient β = 4.6, P Conclusion: the present study identifies −675 4G/5G not −844 G/A polymorphism of PAI gene as the principal determinant of plasma PAI-1 level in Tunisian T2D patients, the android fat distribution, dyslipidemia and hyperglycemia play a modest role in this variation.
文摘Tissue plasminogen activator(t PA)use in the treatment of ischemic stroke:t PA is a serine protease that catalyzes the breakdown of blood clots.Because of its thrombolytic properties,t PA is used to treat specific types of stroke,including ischemia,but is contraindicated for treatment of hemorrhagic stroke or head trauma.Although a life saving and powerful‘clot buster’,t PA has a
文摘Objective: To study the expression and clinicalsignificance of urokinase-type plasminogen activator(uPA) in breast cancer. Methods: Applyingstreptavidin-biotin complex (SABC) immunohistochemical technique, expression of uPA was studied in100 patients with primary breast canceL Results: Therewere 55 patients with high uPA expression, and 45 withlower expression. There was significant correlationbetween uPA expression and TNM stage, lymph nodestatus, and the tumor size. Neither age, menopausalstatus, nor ER status was significantly related with levelof uPA expression. The patients with high expression ofuPA had significantly shorter disease-free survival (DFS)and overall survival (OS) than did those with lowexpression of uPA. Univariate analysis showed that uPAas a prognostic factor was of similar magnitude tolymph node status and TNM stage, hut stronger thanthat of ER status and tumor size. UPA was anindependent prognostic factor affecting disease-freesurvival and overall survival. Collclusion: uPA appearsto be a strong and independent biologic marker forpredicting prognosis of breast cancer.
文摘In order to further investigate the effect of annexinⅡ(Ann Ⅱ) on tissue plasminogen activator (t PA) dependent plasminogen (PLG) activation and its interactive mechanism, recombinant native Ann Ⅱ bound t PA, PLG and plasmin with high affinity was examined. The flow cytometric assay showed that the ann Ⅱexpression rate was higher in the human umbilical vein endothelial cell (HUVEC) (87 65 %) than in the HL 60 cells as controls (35.79 %). Two irrelevant proteins, bovine serum albumin (BSA) and equine IgG (EIG) had no effect on the production of plasmin. Ann Ⅱ mediated enhancement of t PA dependent PLG activation was inhibited by ε aminocaproic acid or by pretreatment of Ann Ⅱ with carboxypeptidase B with the inhibitive rate being 77.8 % and 77.0 %, respectively. It was revealed that the effect of Ann Ⅱon PLG activation was specific for t PA. Urokinase didn’t bind to Ann Ⅱ, demonstrating the role of receptor related lysine residues on activation of PLG, showing that the Ann Ⅱ PLG interaction was dependent upon carboxyl terminal lysine residues. These findings suggest that annexin Ⅱ mediated co assembly of t PA and PLG may promote plasmin generation and play a key role in modulating fibrinolysis on the endothelial surface.
基金The project supported by the Natural Science Foundation of Fujian Province(2007J0008and C0720002)the Training Program of Fujian Excellent Talents in University
文摘OBJECTIVE To investigate the thrombolytic and antiplatelet effects of a novel plasminogen activator from the venom of Gloydius brevicaudus viper(GBV-PA)in vitro and in vivo.METHODS Thrombolytic experiments were performed in rabbit models of ear vein thrombosis and carotid artery thrombosis,and in dog model of acute cerebral infarction.Inhibition of thrombus formation was evaluated in rat inferior vena cava thrombosis model and ferric chloride-induced arterial thrombosis.In vitro,we assayed the antithrombotic effect of GBV-PA on rabbit blood clots,euglobulin lysis time(ELT)of rabbit plasma,and on ADP-induced platelet aggregation.RESULTS GBV-PA intravenous administ ration significantly reduced vascular recanalization times of rabbit ear veins thrombosis and thrombus weight of rabbit carotid artery thrombosis.The arterial recanalization rates were dose-and time-dependently improved after administration of GBV-PA in canine acute cerebral infarction model.Thrombus length and weight was significantly reduced by GBV-PA both in rat inferior vena cava and ferric chloride-induced arterial thrombosis models.Thrombus formation of blood of rabbits they were administrated with GBV-PA was also inhibited.GBV-PA radically reduced plasma ELT of rabbit′s blood clots.ADP-induced platelet aggregation was inhibited by GBV-PA in a dose-dependent manner with a half-maximal inhibitory concentration of 19.9μg·mL-1.CONCLUSION This study demonstrates that GBV-PA is a thrombolytic and antiplatelet agent.It has significant antithrombotic effects on various in vitro and in vivo experimental models of thrombosis.The mechanisms that underline its antithrombotic effects were related to GBV-PA′s capabilities of increasing fibrinolytic activities and inhibition of platelet aggregation.
文摘Objective To observe the changes of the activity of tissue -type plasminogen activa tor(TPA)after asphyxia.Methods As-phyxia was induced in mouse pups by performing a ‘delayed cesarean section’.The experiment was designed for a co ntrol group and 4asphyctic groups to detect the activity of TPA.Results TPAactivity of brain increased afte r asphyxia(P <0.01).Conclusion TPAincreased after asphyxia might be able to attack the b asement membrane of microvessels,t hen opened the blood -brain barrier a nd induced neuronal damage.
文摘Tandem internal carotid and middle cerebral artery occlusion after carotid dissection predicts poor outcome after systemic thrombolysis. Current treatments include the use of endovascular carotid stenting, which carries with it a high risk of propagating further embolic events and worsening the dissection. New strategies for avoiding the aforementioned side-effects include recanalization using cross-collaterals for delivery of intra-lesional tissue plasminogen activator(t PA). We present two cases that provide further support for this novel approach. Both patients presented with a National Institute of Health Stroke Scale of 20, received intra-arterial t PA via cross-collateralization, and made full recoveries without the need for stenting.
文摘Dear Sir,We congratulate Wu et al[1] for their study entitled'Roles of tissue plasminogen activator and its inhibitor in proliferative diabetic retinopathy'.The authors investigated the effects of tissue plasminogen activator（t-PA）and plasminogen activator inhibitor（PAI）in the pathogenesis of proliferative diabetic retinopathy（PDR）.The authors reported that t-PA and PAI are involved in the pathogenesis of PDR.
