Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not...Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well understood.Type-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is absent.Immunofluorescence was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory columns.Parenchymal and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,CD34/CD39.LIF immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/CD118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,cytoarchitecture.These neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent precursors.Dissociated cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage cells.Fluorescence-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in culture.This is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal cords.Our data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterized by surface BMPRⅡ^(+)hNPCs.Our study has provided a new methodology for an in vitro model capable of amplifying human fetal spinal cord cell numbers for>10 passages.Investigations of the role BMPRⅡplays in spinal cord development have primarily relied upon mouse and rat models,with interpolations to human development being derived through inference.Because of significant species differences between murine biology and human,including anatomical dissimilarities in central nervous system(CNS)structure,the findings made in murine models cannot be presumed to apply to human spinal cord development.For these reasons,our human in vitro model offers a novel tool to better understand neurodevelopmental pathways,including BMP signaling,as well as spinal cord injury research and testing drug therapies.展开更多
目的:探讨血清生物标志物甲胎蛋白(AFP)、维生素K缺失或拮抗剂Ⅱ诱导的蛋白质(PIVKA-Ⅱ)和磷脂酰肌醇蛋白聚糖3(GPC-3)单独或联合用于肝细胞癌(以下简称肝癌)诊断的价值。方法:检索PubMed、Web of Science、Embase三个数据库,收集2002...目的:探讨血清生物标志物甲胎蛋白(AFP)、维生素K缺失或拮抗剂Ⅱ诱导的蛋白质(PIVKA-Ⅱ)和磷脂酰肌醇蛋白聚糖3(GPC-3)单独或联合用于肝细胞癌(以下简称肝癌)诊断的价值。方法:检索PubMed、Web of Science、Embase三个数据库,收集2002年以来发表的AFP、PIVKA-Ⅱ和GPC-3单独或联合用于诊断肝癌的文献。根据纳入和排除标准筛选文献并提取相关数据。利用诊断准确性研究的质量评价(QUADAS)检查表对纳入的文献进行质量评价,并采用Meta DiSc软件、Review Manager 5.4软件和Stata 15.1软件对AFP、PIVKA-Ⅱ和GPC-3单用和联合使用诊断肝癌的受试者工作特征曲线下面积(AUC)、敏感度、特异度等指标进行数据分析。结果:共纳入32篇文献。Meta分析结果显示,单个标志物用于诊断肝癌时,PIVKA-Ⅱ的AUC值最高,为0.88(95%CI:0.85~0.91),其次是GPC-3和AFP;多个标志物联合用于诊断肝癌的AUC均高于单个标志物,其中PIVKA-Ⅱ联合GPC-3诊断的AUC值最高,为0.90(95%CI:0.87~0.92)。单个标志物用于诊断肝癌时,PIVKA-Ⅱ和GPC-3的敏感度相对较高(分别为0.75和0.76),但GPC-3的特异度不如PIVKA-Ⅱ和AFP(AFP、PIVKA-Ⅱ和GPC-3分别为0.87、0.88和0.81);多个标志物联合用于诊断肝癌的敏感度较单个标志物诊断时有所提高,但特异度无明显提高。单个标志物用于诊断肝癌时,PIVKA-Ⅱ的诊断比值比(DOR)最高,为22(95%CI:13~36),其次是GPC-3和AFP;两个标志物联合用于诊断肝癌的DOR均高于单个标志物,其中AFP联合GPC-3诊断的DOR最高,为25(95%CI:9~67);三个标志物联合用于诊断肝癌时的DOR明显降低,为10(95%CI:7~45)。结论:单个标志物用于肝癌诊断时,PIVKA-Ⅱ的诊断价值更高。两种标志物联合能显著提高肝癌诊断的敏感度,三种标志物联合未能进一步提高诊断价值。结合临床实际,推荐AFP联合PIVKA-Ⅱ用于肝癌的诊断。展开更多
Background: As a promising biomarker of hepatocellular carcinoma(HCC), protein induced by vitamin K absence or antagonist-Ⅱ(PIVKA-Ⅱ) has been studied extensively. However, its diagnostic capability varies across HCC...Background: As a promising biomarker of hepatocellular carcinoma(HCC), protein induced by vitamin K absence or antagonist-Ⅱ(PIVKA-Ⅱ) has been studied extensively. However, its diagnostic capability varies across HCC studies. This study aimed to compare the performance of PIVKA-Ⅱ with alpha-fetoprotein(AFP) in the diagnosis of HCC. Data sources: A systematic literature search was conducted to identify the studies from MEDLINE, Embase and Cochrane Library Databases, which were published up to December 20, 2017 to compare the diagnostic capability of PIVKA-Ⅱ and AFP for HCC. The data were pooled using random effects model. Pooled sensitivity and specificity were calculated. Summary receiver operating characteristic curve(ROC) was employed to evaluate the diagnostic accuracy of each marker. Results: Thirty-one studies were included. The pooled sensitivity(95% CI) of PIVKA-Ⅱ and AFP was 0.66(0.65–0.68) and 0.66(0.65–0.67), respectively in diagnosis of HCC; and the corresponding pooled specificity(95% CI) was 0.89(0.88–0.90) and 0.84(0.83–0.85), respectively. The area under the ROC curve(AUC) of PIVKA-Ⅱ and AFP was 0.856(0.817–0.895) and 0.770(0.728–0.811), respectively. Subgroup analysis showed that PIVKA-Ⅱ was superior to AFP in terms of the AUC for both small HCC( < 3 cm) [0.863(0.825–0.901) vs 0.717(0.658–0.776)] and large HCC( ≥ 3 cm) [0.854(0.811–0.897) vs 0.729(0.682–0.776)]; for American [0.926(0.897–0.955) vs 0.698(0.594–0.662)], European [0.772(0.743–0.801) vs 0.628(0.594–0.662)], Asian [0.838(0.812–0.864) vs 0.785(0.764–0.806)] and African [0.812(0.794–0.840) vs 0.721(0.675–0.767)] HCC patients; and for HBV-related [0.909(0.866–0.951) vs 0.714(0.673–0.755)] and mixed-etiology [0.847(0.821–0.873) vs 0.794(0.772–0.816)] HCC. Conclusion: This meta-analysis indicates that PIVKA-Ⅱ is better than AFP in terms of the accuracy for diagnosing HCC, regardless of tumor size, patient ethnic group, or HCC etiology.展开更多
SDF-1α,a ligand for the chemokine receptor CXCR4,is well known for mediating the migration of breast cancer cells.In a previous study we demonstrated that a synthetic 21-mer peptide antagonist of CXCR4（NT21MP） deri...SDF-1α,a ligand for the chemokine receptor CXCR4,is well known for mediating the migration of breast cancer cells.In a previous study we demonstrated that a synthetic 21-mer peptide antagonist of CXCR4（NT21MP） derived from the viral macrophage inflammatory protein Ⅱ could antagonize tumor growth in vivo by inhibiting cellular proliferation and inducing apoptosis in breast cancer cells.However,the role of SDF-1α in the signaling pathways underlying the proliferation of human breast cancer cells and associated signaling pathways and inhibiting signal pathways of NT21MP remained unclear.The present study investigated the mechanism of NT21MP on anti-tumor in breast cancer in vitro.The effect of NT21MP on the viability of cells was determined by the MTT assay.Annexin V-FITC and PI staining was performed to detect early stage apoptosisin SKBR3 cells treated with SDF-1α and AMD3100 or NT21MP.Western blotting techniques were used to assay the composition of phosphoproteomics and total proteins present in the SKBR3 breast cancer cells.RT-PCR and Western blotting technique were used to detect the effect of NT21MP and AMD3100 on Bcl-2 and Bax expression.The results indicated that SDF-1α prevented apoptosis and promoted the proliferation of SKBR3 human breast cancer cells.As compared with untreated SKBR3 cells,Treatment with SDF-1α significantly increased cell viability,and NT21MP abolished the protective effects of SDF-1α dose-dependently（P0.05）.There was a significant decrease in the percentage of apoptotic cells after SDF-1α treatment as compared with control group（2.7%±0.2% vs.5.7%±0.4%,P0.05）.But pretreatment of SKBR3 cells with NT21MP significantly attenuated the antiapoptotic effects of SDF-1α as compared with SKBR3 cells without NT21MP pretreatment.The proliferative and anti-apoptotic effects of SDF-1α in SKBR3 cells were associated with an increase in AKT and ERK1/2 phosphorylation as well as a decrease in Bax expression and an increase in Bcl-2 expression.These changes in intracellular processes were blocked by NT21MP in a dose-dependent manner（P0.05）.In conclusion,NT21MP efficiently inhibits SDF-1α-induced proliferation and antiapoptosis in SKBR3 cells by reducing the levels of phosphorylated AKT and ERK1/2,as well as decreasing the ratio of expression of Bcl-2 relative to Bax.展开更多
Glycosides of Cistanche（GC）is a preparation used extensively for its neuroprotective effect against neurological diseases,but its mechanisms of action remains incompletely understood.Here,we established a bilateral ...Glycosides of Cistanche（GC）is a preparation used extensively for its neuroprotective effect against neurological diseases,but its mechanisms of action remains incompletely understood.Here,we established a bilateral common carotid artery occlusion model of vascular dementia in rats and injected the model rats with a suspension of GC（10 mg/kg/day,intraperitoneally）for 14 consecutive days.Immunohistochemistry showed that GC significantly reduced p-tau and amyloid beta（Aβ）immunoreactivity in the hippocampus of the model rats.Proteomic analysis demonstrated upregulation of mitochondrial precursor protein and downregulation of keratin type II cytoskeletal6A after GC treatment compared with model rats that had received saline.Western blot assay confirmed these findings.Our results suggest that the neuroprotective effect of GC in vascular dementia occurs via the promotion of neuronal cytoskeleton regeneration.展开更多
Protein induced by vitamin K absence or antagonist Ⅱ(PIVKA-Ⅱ) is a putative specific marker of hepatocellular carcinoma(HCC),but it may also be produced by asmall number of gastric cancers.To date,16 cases of PIVKA-...Protein induced by vitamin K absence or antagonist Ⅱ(PIVKA-Ⅱ) is a putative specific marker of hepatocellular carcinoma(HCC),but it may also be produced by asmall number of gastric cancers.To date,16 cases of PIVKA-Ⅱ-producing gastric cancer have been reported,2 of which were reported by us and all of which were identified in Japan.There are no symptoms specific to PIVKA-Ⅱ-producing gastric cancer,and the representative clinical symptoms are general fatigue,appetite loss,and upper abdominal pain.Serum alpha-feto-protein(AFP)levels are also increased in almost allcases.Liver metastasis is observed in approximately 80% of cases and portal vein tumor thrombus is ob-served in approximately 20% of cases.Differential diagnosis between metastatic liver tumor and HCC is often difficult.Grossly,almost all cases appear as advanced gastric cancer.Histologically,a hepatoid pattern is observed in many cases,in addition to a moderately to poorly differentiated adenocarcinoma component.The production of PIVKA-Ⅱ and AFP is usually confirmed using immunohistochemical staining.Treatment and prognosis largely depends on the existence of liver meta-stasis,and the prognosis of patients with liver metas-tasis is very poor.PIVKA-Ⅱ may be produced during the hepatocellular metaplasia of the tumor cells.展开更多
Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to de...Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to determine the effects of the calmodulin-dependent protein kinase(CaMK) Ⅱ inhibitor,KN-93,on L-type calcium current(I Ca,L) and early after-depolarizations(EADs) in hypertrophic cardiomyocytes.A rabbit model of myocardial hypertrophy was constructed through abdominal aortic coarctation(LVH group).The control group(sham group) received a sham operation,in which the abdominal aortic was dissected but not coarcted.Eight weeks later,the degree of left ventricular hypertrophy(LVH) was evaluated using echocardiography.Individual cardiomyocyte was isolated through collagenase digestion.Action potentials(APs) and I Ca,L were recorded using the perforated patch clamp technique.APs were recorded under current clamp conditions and I Ca,L was recorded under voltage clamp conditions.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were observed under the conditions of low potassium(2 mmol/L),low magnesium(0.25 mmol/L) Tyrode’s solution perfusion,and slow frequency(0.25-0.5 Hz) electrical stimulation.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were also evaluated after treatment with different concentrations of KN-92(KN-92 group) and KN-93(KN-93 group).Eight weeks later,the model was successfully established.Under the conditions of low potassium,low magnesium Tyrode’s solution perfusion,and slow frequency electrical stimulation,the incidence of EADs was 0/12,11/12,10/12,and 5/12 in sham group,LVH group,KN-92 group(0.5 μmol/L),and KN-93 group(0.5 μmol/L),respectively.When the drug concentration was increased to 1 μmol/L in KN-92 group and KN-93 group,the incidence of EADs was 10/12 and 2/12,respectively.At 0 mV,the current density was 6.7±1.0 and 6.3±0.7 PA·PF-1 in LVH group and sham group,respectively(P>0.05,n=12).When the drug concentration was 0.5 μmol/L in KN-92 and KN-93 groups,the peak I Ca,L at 0 mV was decreased by(9.4±2.8)% and(10.5±3.0)% in the hypertrophic cardiomyocytes of the two groups,respectively(P>0.05,n=12).When the drug concentration was increased to 1 μmol/L,the peak I Ca,L values were lowered by(13.4±3.7)% and(40±4.9)%,respectively(P<0.01,n=12).KN-93,a specific inhibitor of CaMKII,can effectively inhibit the occurrence of EADs in hypertrophic cardiomyocytes partially by suppressing I Ca,L,which may be the main action mechanism of KN-93 antagonizing the occurrence of ventricular arrhythmias in hypertrophic myocardium.展开更多
基金supported by grants from the National Health and Medical Research Council(NHMRC)of Australia(Nos.571100 and 1048082)the Baxter Charitable Foundation(to TCL)+1 种基金Medical Research grants from the Rebecca L.Cooper Medical Research Foundation(to MWW,TCL,and MDL)supported by a Charles D.Kelman,M.D.Postdoctoral Award(2010)from the International Retinal Research Foundation(USA)。
文摘Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well understood.Type-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is absent.Immunofluorescence was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory columns.Parenchymal and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,CD34/CD39.LIF immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/CD118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,cytoarchitecture.These neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent precursors.Dissociated cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage cells.Fluorescence-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in culture.This is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal cords.Our data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterized by surface BMPRⅡ^(+)hNPCs.Our study has provided a new methodology for an in vitro model capable of amplifying human fetal spinal cord cell numbers for>10 passages.Investigations of the role BMPRⅡplays in spinal cord development have primarily relied upon mouse and rat models,with interpolations to human development being derived through inference.Because of significant species differences between murine biology and human,including anatomical dissimilarities in central nervous system(CNS)structure,the findings made in murine models cannot be presumed to apply to human spinal cord development.For these reasons,our human in vitro model offers a novel tool to better understand neurodevelopmental pathways,including BMP signaling,as well as spinal cord injury research and testing drug therapies.
基金supported in part by the National Natural Sci-ence Foundation of China(81472284 and 81672699)Shanghai Pujiang Program(16PJD004)
文摘Background: As a promising biomarker of hepatocellular carcinoma(HCC), protein induced by vitamin K absence or antagonist-Ⅱ(PIVKA-Ⅱ) has been studied extensively. However, its diagnostic capability varies across HCC studies. This study aimed to compare the performance of PIVKA-Ⅱ with alpha-fetoprotein(AFP) in the diagnosis of HCC. Data sources: A systematic literature search was conducted to identify the studies from MEDLINE, Embase and Cochrane Library Databases, which were published up to December 20, 2017 to compare the diagnostic capability of PIVKA-Ⅱ and AFP for HCC. The data were pooled using random effects model. Pooled sensitivity and specificity were calculated. Summary receiver operating characteristic curve(ROC) was employed to evaluate the diagnostic accuracy of each marker. Results: Thirty-one studies were included. The pooled sensitivity(95% CI) of PIVKA-Ⅱ and AFP was 0.66(0.65–0.68) and 0.66(0.65–0.67), respectively in diagnosis of HCC; and the corresponding pooled specificity(95% CI) was 0.89(0.88–0.90) and 0.84(0.83–0.85), respectively. The area under the ROC curve(AUC) of PIVKA-Ⅱ and AFP was 0.856(0.817–0.895) and 0.770(0.728–0.811), respectively. Subgroup analysis showed that PIVKA-Ⅱ was superior to AFP in terms of the AUC for both small HCC( < 3 cm) [0.863(0.825–0.901) vs 0.717(0.658–0.776)] and large HCC( ≥ 3 cm) [0.854(0.811–0.897) vs 0.729(0.682–0.776)]; for American [0.926(0.897–0.955) vs 0.698(0.594–0.662)], European [0.772(0.743–0.801) vs 0.628(0.594–0.662)], Asian [0.838(0.812–0.864) vs 0.785(0.764–0.806)] and African [0.812(0.794–0.840) vs 0.721(0.675–0.767)] HCC patients; and for HBV-related [0.909(0.866–0.951) vs 0.714(0.673–0.755)] and mixed-etiology [0.847(0.821–0.873) vs 0.794(0.772–0.816)] HCC. Conclusion: This meta-analysis indicates that PIVKA-Ⅱ is better than AFP in terms of the accuracy for diagnosing HCC, regardless of tumor size, patient ethnic group, or HCC etiology.
基金supported by a grant from the National Natural Sciences Foundation of China (No. 81071848)a grant from a Key Program of Anhui Educational Committee(No. KJ2010A240)
文摘SDF-1α,a ligand for the chemokine receptor CXCR4,is well known for mediating the migration of breast cancer cells.In a previous study we demonstrated that a synthetic 21-mer peptide antagonist of CXCR4（NT21MP） derived from the viral macrophage inflammatory protein Ⅱ could antagonize tumor growth in vivo by inhibiting cellular proliferation and inducing apoptosis in breast cancer cells.However,the role of SDF-1α in the signaling pathways underlying the proliferation of human breast cancer cells and associated signaling pathways and inhibiting signal pathways of NT21MP remained unclear.The present study investigated the mechanism of NT21MP on anti-tumor in breast cancer in vitro.The effect of NT21MP on the viability of cells was determined by the MTT assay.Annexin V-FITC and PI staining was performed to detect early stage apoptosisin SKBR3 cells treated with SDF-1α and AMD3100 or NT21MP.Western blotting techniques were used to assay the composition of phosphoproteomics and total proteins present in the SKBR3 breast cancer cells.RT-PCR and Western blotting technique were used to detect the effect of NT21MP and AMD3100 on Bcl-2 and Bax expression.The results indicated that SDF-1α prevented apoptosis and promoted the proliferation of SKBR3 human breast cancer cells.As compared with untreated SKBR3 cells,Treatment with SDF-1α significantly increased cell viability,and NT21MP abolished the protective effects of SDF-1α dose-dependently（P0.05）.There was a significant decrease in the percentage of apoptotic cells after SDF-1α treatment as compared with control group（2.7%±0.2% vs.5.7%±0.4%,P0.05）.But pretreatment of SKBR3 cells with NT21MP significantly attenuated the antiapoptotic effects of SDF-1α as compared with SKBR3 cells without NT21MP pretreatment.The proliferative and anti-apoptotic effects of SDF-1α in SKBR3 cells were associated with an increase in AKT and ERK1/2 phosphorylation as well as a decrease in Bax expression and an increase in Bcl-2 expression.These changes in intracellular processes were blocked by NT21MP in a dose-dependent manner（P0.05）.In conclusion,NT21MP efficiently inhibits SDF-1α-induced proliferation and antiapoptosis in SKBR3 cells by reducing the levels of phosphorylated AKT and ERK1/2,as well as decreasing the ratio of expression of Bcl-2 relative to Bax.
基金supported by the National Natural Science Foundation of China,No.30960520the Natural Science Foundation of Inner Mongolia Autonomous Region of China,No.2016MS0837
文摘Glycosides of Cistanche（GC）is a preparation used extensively for its neuroprotective effect against neurological diseases,but its mechanisms of action remains incompletely understood.Here,we established a bilateral common carotid artery occlusion model of vascular dementia in rats and injected the model rats with a suspension of GC（10 mg/kg/day,intraperitoneally）for 14 consecutive days.Immunohistochemistry showed that GC significantly reduced p-tau and amyloid beta（Aβ）immunoreactivity in the hippocampus of the model rats.Proteomic analysis demonstrated upregulation of mitochondrial precursor protein and downregulation of keratin type II cytoskeletal6A after GC treatment compared with model rats that had received saline.Western blot assay confirmed these findings.Our results suggest that the neuroprotective effect of GC in vascular dementia occurs via the promotion of neuronal cytoskeleton regeneration.
文摘Protein induced by vitamin K absence or antagonist Ⅱ(PIVKA-Ⅱ) is a putative specific marker of hepatocellular carcinoma(HCC),but it may also be produced by asmall number of gastric cancers.To date,16 cases of PIVKA-Ⅱ-producing gastric cancer have been reported,2 of which were reported by us and all of which were identified in Japan.There are no symptoms specific to PIVKA-Ⅱ-producing gastric cancer,and the representative clinical symptoms are general fatigue,appetite loss,and upper abdominal pain.Serum alpha-feto-protein(AFP)levels are also increased in almost allcases.Liver metastasis is observed in approximately 80% of cases and portal vein tumor thrombus is ob-served in approximately 20% of cases.Differential diagnosis between metastatic liver tumor and HCC is often difficult.Grossly,almost all cases appear as advanced gastric cancer.Histologically,a hepatoid pattern is observed in many cases,in addition to a moderately to poorly differentiated adenocarcinoma component.The production of PIVKA-Ⅱ and AFP is usually confirmed using immunohistochemical staining.Treatment and prognosis largely depends on the existence of liver meta-stasis,and the prognosis of patients with liver metas-tasis is very poor.PIVKA-Ⅱ may be produced during the hepatocellular metaplasia of the tumor cells.
基金supported by grants from the Fujian Provincial Natural Science Foundation of China (No. 2008J0075)the Fujian Provincial Science and Technology Project of China(No. 2010Y0011)
文摘Cardiac hypertrophy is an independent risk factor for sudden cardiac death in clinical settings and the incidence of sudden cardiac death and ventricular arrhythmias are closely related.The aim of this study was to determine the effects of the calmodulin-dependent protein kinase(CaMK) Ⅱ inhibitor,KN-93,on L-type calcium current(I Ca,L) and early after-depolarizations(EADs) in hypertrophic cardiomyocytes.A rabbit model of myocardial hypertrophy was constructed through abdominal aortic coarctation(LVH group).The control group(sham group) received a sham operation,in which the abdominal aortic was dissected but not coarcted.Eight weeks later,the degree of left ventricular hypertrophy(LVH) was evaluated using echocardiography.Individual cardiomyocyte was isolated through collagenase digestion.Action potentials(APs) and I Ca,L were recorded using the perforated patch clamp technique.APs were recorded under current clamp conditions and I Ca,L was recorded under voltage clamp conditions.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were observed under the conditions of low potassium(2 mmol/L),low magnesium(0.25 mmol/L) Tyrode’s solution perfusion,and slow frequency(0.25-0.5 Hz) electrical stimulation.The incidence of EADs and I ca,L in the hypertrophic cardiomyocytes were also evaluated after treatment with different concentrations of KN-92(KN-92 group) and KN-93(KN-93 group).Eight weeks later,the model was successfully established.Under the conditions of low potassium,low magnesium Tyrode’s solution perfusion,and slow frequency electrical stimulation,the incidence of EADs was 0/12,11/12,10/12,and 5/12 in sham group,LVH group,KN-92 group(0.5 μmol/L),and KN-93 group(0.5 μmol/L),respectively.When the drug concentration was increased to 1 μmol/L in KN-92 group and KN-93 group,the incidence of EADs was 10/12 and 2/12,respectively.At 0 mV,the current density was 6.7±1.0 and 6.3±0.7 PA·PF-1 in LVH group and sham group,respectively(P>0.05,n=12).When the drug concentration was 0.5 μmol/L in KN-92 and KN-93 groups,the peak I Ca,L at 0 mV was decreased by(9.4±2.8)% and(10.5±3.0)% in the hypertrophic cardiomyocytes of the two groups,respectively(P>0.05,n=12).When the drug concentration was increased to 1 μmol/L,the peak I Ca,L values were lowered by(13.4±3.7)% and(40±4.9)%,respectively(P<0.01,n=12).KN-93,a specific inhibitor of CaMKII,can effectively inhibit the occurrence of EADs in hypertrophic cardiomyocytes partially by suppressing I Ca,L,which may be the main action mechanism of KN-93 antagonizing the occurrence of ventricular arrhythmias in hypertrophic myocardium.
