The plasma membrane fortion isolated from primp leaves of 14 d soybean shoot showed Protein kinase (PK) and protein phosphatase (PP) activities (Fig. 1 ), and these activities declined dramaically when the leaves unde...The plasma membrane fortion isolated from primp leaves of 14 d soybean shoot showed Protein kinase (PK) and protein phosphatase (PP) activities (Fig. 1 ), and these activities declined dramaically when the leaves underwent senescence-inducing treatment (Table 1 ). 6-BA pretreatment, which showed retarding effect on soybean leaf senescence, could sustain the activities of both PKs and PPs during the senescence-inducing treatment (Table 1 ). The results of autoradiogra phy suggested that the main PKs whose activities declined during leaf senescence were calcium-dependent Protein kinases (Fig. 3). The potent and specif ic inhibitor of Protein phosphatase 1 and 2A, okadric acid, could fasten leaf senescence. These results impied thatretaining the balance of plasma membrane protein phosphorylation/ dephosphorylation was the key action of exogenous 6-BA in retarding leat senescence.展开更多
AIM:The current study was to determine the serum/pLasma levels of VEGF,IL-6,malondialdehyde (MDA),nitric oxide (NO),PCT and CRP in gastric carcinoma and correlation with the stages of the disease and accompanying infe...AIM:The current study was to determine the serum/pLasma levels of VEGF,IL-6,malondialdehyde (MDA),nitric oxide (NO),PCT and CRP in gastric carcinoma and correlation with the stages of the disease and accompanying infection. METHODS:We examined the levels of serum VEGF,IL-6, PCT,CRP and plasma MDA,NO in 42 preoperative gastric cancer patients and 23 healthy subjects.There were infection anamneses that had no definite origin in 19 cancer patients. RESULTS:The VEGF levels (mean±SD; pg/mL) were 478.05±178.29 and 473.85±131.24 in gastric cancer patients with and without infection,respectively,and these values were not significantly different (P>0.05).The levels of VEGF, CRP,PCT,It-6,MDA and NO in cancer patients were significantly higher than those in healthy controls and the levels of CRP,PCT,It-6,MDA and NO were statistically increased in infection group when compared with non- infection group (P<0.001). CONCLUSION:Although serum VEGF concentrations were increased in gastric cancer,this increase might not be related to infection.CRP,PCT,IL-6,MDA and NO have obvious drawbacks in the diagnosis of infections in cancer patients. These markers may not help to identify infections in the primary evaluation of cancer patients and hence to avoid unnecessary antibiotic treatments as well as hospitalization. According to the results of this study,IL-6,MDA,NO and especially VEGF can be used as useful parameters to diagnose and grade gastric cancer.展开更多
目的:分析急性肺损伤中IL-6与肺表面活性蛋白-A(surfactant protein A,SP-A)和SP-B的含量变化及其相互关系,探讨急性肺损伤的发病机制。方法:用Wistar大鼠复制油酸性急性肺损伤动物模型,在不同时间点收集急性肺损伤大鼠血清标本及肺泡...目的:分析急性肺损伤中IL-6与肺表面活性蛋白-A(surfactant protein A,SP-A)和SP-B的含量变化及其相互关系,探讨急性肺损伤的发病机制。方法:用Wistar大鼠复制油酸性急性肺损伤动物模型,在不同时间点收集急性肺损伤大鼠血清标本及肺泡灌洗液(bronchoalveo larlavage fluid,BALF),用放射免疫法测定血清细胞因子IL-6的动态变化;采用ELISA法检测BALF中SP-A、SP-B含量的变化。结果与结论:急性肺损伤后大鼠血清中细胞因子IL-6的分泌水平显著上升(P<0.05),而BALF中SP-A、SP-B含量显著降低,且血清中IL-6含量升高与BALF中SP-A、SP-B下降幅度呈显著负相关。结果提示急性肺损伤中IL-6分泌的升高与肺表面活性蛋白SP-A、SP-B含量的降低有显著的相关关系,炎症细胞因子IL-6可能通过影响SP-A、SP-B的表达产生致病作用。展开更多
N^6-methyladenosine(m^6A)emerges as an important modification in eukaryotic mRNAs.m^6A has first been reported in 1974,and its functional significance in mammalian gene regulation and importance for proper development...N^6-methyladenosine(m^6A)emerges as an important modification in eukaryotic mRNAs.m^6A has first been reported in 1974,and its functional significance in mammalian gene regulation and importance for proper development have been well established.An arsenal of writer,eraser,and reader proteins accomplish deposition,removal,and interpretation of the m^6A mark,resulting in dynamic function.This led to the concept of an epitranscriptome,the compendium of RNA species with chemical modification ofthe nucleobases in the cell,in analogy to the epigenome.While m^6A has long been known to also exist in plant mRNAs,proteins involved in m^6A metabolism have only recently been detected by mutant analysis,homology search,and mRNA interactome capture in the reference plant Arabidopsis thaliana.Dysregulation ofthe m^6A modification causes severe developmental abnormalities of leaves and roots and altered timing of reproductive development.Furthermore,m^6A modification affects viral infection.Here,we discuss recent progress in identifying m^6A sites transcriptome-wide,in identifying the molecular players involved in writing,removing,and reading the mark,and in assigning functions to this RNA modification in 4.thaliana.We highlight similarities and differences to m^6A modification in mammals and provide an outlook on important questions that remain to be addressed.展开更多
RNA interference (RNAi) is triggered by the presence of a double-stranded RNA (dsRNA), and results in the silencing of homologous gene expression through the specific degradation of an mRNA containing the same sequenc...RNA interference (RNAi) is triggered by the presence of a double-stranded RNA (dsRNA), and results in the silencing of homologous gene expression through the specific degradation of an mRNA containing the same sequence. dsRNAmediated RNAi can be used in a wide variety of eucaryotes to induce the sequence-specific inhibition of gene expression.Synthetic 21-23 nucleotide (nt) small interfering RNA (siRNA) with 2 nt 3' overhangs was recently found to mediate efficient sequence-specific mRNA degradation in mammalian cells. Here, we studied the effects of synthetic siRNA duplexes targeted to SARS coronavirus structural proteins E, M, and N in a cell culture system. Among total 26 siRNA duplexes, we obtained 3 siRNA duplexes which could sequence-specifically reduce target genes expression over 80％ at the concentration of 60 nM in Vero E6 cells. The downregulation effect was in correlation with the concentrations of the siRNA duplexes in a range of 0～60 nM. Our results also showed that many inactive siRNA duplexes may be brought to life simply by unpairing the 5' end of the antisense strands. Results suggest that siRNA is capable of inhibiting SARS coronavirus genes expression and thus may be a new therapeutic strategy for treatment of SARS.展开更多
文摘The plasma membrane fortion isolated from primp leaves of 14 d soybean shoot showed Protein kinase (PK) and protein phosphatase (PP) activities (Fig. 1 ), and these activities declined dramaically when the leaves underwent senescence-inducing treatment (Table 1 ). 6-BA pretreatment, which showed retarding effect on soybean leaf senescence, could sustain the activities of both PKs and PPs during the senescence-inducing treatment (Table 1 ). The results of autoradiogra phy suggested that the main PKs whose activities declined during leaf senescence were calcium-dependent Protein kinases (Fig. 3). The potent and specif ic inhibitor of Protein phosphatase 1 and 2A, okadric acid, could fasten leaf senescence. These results impied thatretaining the balance of plasma membrane protein phosphorylation/ dephosphorylation was the key action of exogenous 6-BA in retarding leat senescence.
文摘AIM:The current study was to determine the serum/pLasma levels of VEGF,IL-6,malondialdehyde (MDA),nitric oxide (NO),PCT and CRP in gastric carcinoma and correlation with the stages of the disease and accompanying infection. METHODS:We examined the levels of serum VEGF,IL-6, PCT,CRP and plasma MDA,NO in 42 preoperative gastric cancer patients and 23 healthy subjects.There were infection anamneses that had no definite origin in 19 cancer patients. RESULTS:The VEGF levels (mean±SD; pg/mL) were 478.05±178.29 and 473.85±131.24 in gastric cancer patients with and without infection,respectively,and these values were not significantly different (P>0.05).The levels of VEGF, CRP,PCT,It-6,MDA and NO in cancer patients were significantly higher than those in healthy controls and the levels of CRP,PCT,It-6,MDA and NO were statistically increased in infection group when compared with non- infection group (P<0.001). CONCLUSION:Although serum VEGF concentrations were increased in gastric cancer,this increase might not be related to infection.CRP,PCT,IL-6,MDA and NO have obvious drawbacks in the diagnosis of infections in cancer patients. These markers may not help to identify infections in the primary evaluation of cancer patients and hence to avoid unnecessary antibiotic treatments as well as hospitalization. According to the results of this study,IL-6,MDA,NO and especially VEGF can be used as useful parameters to diagnose and grade gastric cancer.
文摘目的:分析急性肺损伤中IL-6与肺表面活性蛋白-A(surfactant protein A,SP-A)和SP-B的含量变化及其相互关系,探讨急性肺损伤的发病机制。方法:用Wistar大鼠复制油酸性急性肺损伤动物模型,在不同时间点收集急性肺损伤大鼠血清标本及肺泡灌洗液(bronchoalveo larlavage fluid,BALF),用放射免疫法测定血清细胞因子IL-6的动态变化;采用ELISA法检测BALF中SP-A、SP-B含量的变化。结果与结论:急性肺损伤后大鼠血清中细胞因子IL-6的分泌水平显著上升(P<0.05),而BALF中SP-A、SP-B含量显著降低,且血清中IL-6含量升高与BALF中SP-A、SP-B下降幅度呈显著负相关。结果提示急性肺损伤中IL-6分泌的升高与肺表面活性蛋白SP-A、SP-B含量的降低有显著的相关关系,炎症细胞因子IL-6可能通过影响SP-A、SP-B的表达产生致病作用。
文摘N^6-methyladenosine(m^6A)emerges as an important modification in eukaryotic mRNAs.m^6A has first been reported in 1974,and its functional significance in mammalian gene regulation and importance for proper development have been well established.An arsenal of writer,eraser,and reader proteins accomplish deposition,removal,and interpretation of the m^6A mark,resulting in dynamic function.This led to the concept of an epitranscriptome,the compendium of RNA species with chemical modification ofthe nucleobases in the cell,in analogy to the epigenome.While m^6A has long been known to also exist in plant mRNAs,proteins involved in m^6A metabolism have only recently been detected by mutant analysis,homology search,and mRNA interactome capture in the reference plant Arabidopsis thaliana.Dysregulation ofthe m^6A modification causes severe developmental abnormalities of leaves and roots and altered timing of reproductive development.Furthermore,m^6A modification affects viral infection.Here,we discuss recent progress in identifying m^6A sites transcriptome-wide,in identifying the molecular players involved in writing,removing,and reading the mark,and in assigning functions to this RNA modification in 4.thaliana.We highlight similarities and differences to m^6A modification in mammals and provide an outlook on important questions that remain to be addressed.
基金supported by the Grant No.2003AA208215 from the National High Technology Programs of Chinathe Grant No.30270311 from the National Natural Science Foundation of China.
文摘RNA interference (RNAi) is triggered by the presence of a double-stranded RNA (dsRNA), and results in the silencing of homologous gene expression through the specific degradation of an mRNA containing the same sequence. dsRNAmediated RNAi can be used in a wide variety of eucaryotes to induce the sequence-specific inhibition of gene expression.Synthetic 21-23 nucleotide (nt) small interfering RNA (siRNA) with 2 nt 3' overhangs was recently found to mediate efficient sequence-specific mRNA degradation in mammalian cells. Here, we studied the effects of synthetic siRNA duplexes targeted to SARS coronavirus structural proteins E, M, and N in a cell culture system. Among total 26 siRNA duplexes, we obtained 3 siRNA duplexes which could sequence-specifically reduce target genes expression over 80％ at the concentration of 60 nM in Vero E6 cells. The downregulation effect was in correlation with the concentrations of the siRNA duplexes in a range of 0～60 nM. Our results also showed that many inactive siRNA duplexes may be brought to life simply by unpairing the 5' end of the antisense strands. Results suggest that siRNA is capable of inhibiting SARS coronavirus genes expression and thus may be a new therapeutic strategy for treatment of SARS.
