GTSE1在肝癌中的表达及其对预后和免疫浸润的影响

目的研究G_(2)/S期应答相关蛋白1(G_(2) and S phase-expressed protein 1,GTSE1)在肝细胞癌(hepatocellular carcinoma,HCC)中的表达、免疫学作用和预后分析,及其潜在作用机制。方法使用公共数据库癌症基因组图谱(The Cancer Genome Atlas,TCGA)提供的数据,用Kaplan-Meier、肿瘤免疫评估资源(Tumor Immune Estimation Resource,TIMER)数据库和基因表达谱交互分析(Gene Expression Profiling Interactive Analysis,GEPIA)数据库进行GTSE1基因表达、免疫学作用及预后分析,通过免疫组化实验验证GTSE1在临床样本中的表达,应用R软件对GTSE1相关差异基因进行基因本体(gene ontology,GO)和京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)富集分析。结果GTSE1在人类癌组织中显著高表达,且与肝细胞癌预后不良显著相关(P<0.05);GTSE1基因表达与HCC中浸润性免疫细胞的丰度显著相关(P<0.001)。GTSE1相关的差异表达基因主要富集于核分裂、细胞器裂变、离子通道活性等基因模块;其参与的信号通路主要包括神经活性配体-受体的相互作用、细胞周期等。结论GTSE1在HCC中的表达显著上调并与患者预后不良显著相关,且在免疫细胞浸润中发挥重要作用,可作为HCC的预后标志物和免疫治疗靶点。

Modulating Co-Co bonds average length in Co_(0.85)Se_(1-x)S_(x) to enhance conversion reaction for potassium storage

While alloying transition metal chalcogenides(TMCs)with other chalcogen elements can effectively improve their conductivity and electrochemical properties,the optimal alloying content is still uncertain.In this study,we study the influence of dopant concentration on the chemical bonds in TMC and reveal the associated stepwise conversion reaction mechanism for potassium ion storage.According to density function theory calculations,appropriate S-doping in Co0.85Se(Co_(0.85)Se_(1-x)S_(x))can reduce the average length of Co-Co bonds because of the electronegativity variation,which is thermodynamically favourable to the phase transition reactions.The optimal Se/S ratio(x=0.12)for the conductivity has been obtained from experimental results.When assembled as an anode in potassium-ion batteries(PIBs),the sample with optimized Se/S ratio exhibits extraordinary electrochemical performance.The rate performance(229.2 mA h g^(-1)at 10 A g^(-1))is superior to the state-of-the-art results.When assembled with Prussian blue(PB)as a cathode,the pouch cell exhibits excellent performance,demonstrating its great potential for applications.Moreover,the stepwise K+storage mechanism caused by the coexistence of S and Se is revealed by in-situ X-ray diffraction and ex-situ transmission electron microscopy techniques.Hence,this work not only provides an effective strategy to enhance the electrochemical performance of transition metal chalcogenides but also reveals the underlying mechanism for the construction of advanced electrode materials.

AR、SKP2、SOX10、PD-L1及TIL表达在三阴性乳腺癌中的意义

目的:探索雄激素受体(androgen receptor,AR)、S期激酶相关蛋白2(S-phase kinase-associated protein 2,SKP2)、性别决定区Y相关的HMG盒含因子10(sry-related HMG box-containing factor 10,SOX10)、程序性死亡配体1(programmed death-ligand 1,PD-L1)及肿瘤浸润性淋巴细胞(tumor infiltrating lymphocyte,TIL)在三阴性乳腺癌(triple negative breast cancer,TNBC)表达与临床病理特征和预后的关系。方法:根据苏木精-伊红染色(hematoxylineosin, HE)染色切片评判109例TNBC瘤巢内TIL的比例,采用Leica Bond-Max全自动免疫组化仪检测TNBC组织中AR、SKP2、SOX10、PD-L1的表达。分析以上各生物指标与临床病理特征间的关系,并采用kaplan-Meier、Log-rank进行生存分析。结果:95例患者获得随访,中位随访时间为48个月,中位无病生存时间(disease-free survival, DFS)为42个月,中位总生存时间(overall survival, OS)48个月。在TNBC中,AR阳性表达与淋巴结转移阴性(P=0.009)、肿瘤最大径<2 cm(P=0.008)相关,TIL高表达与低级别TNBC相关(P=0.007),SKP2阳性表达与神经/脉管侵犯阳性(P=0.011)、高级别TNBC相关(P=0.002),SOX10阳性表达与淋巴结转移阳性(P=0.022)、高级别TNBC(P=0.005)相关,PD-L1阳性表达与淋巴结转移阳性(P=0.020)、神经/脉管侵犯阳性(P=0.006)、高级别TNBC(P=0.042)相关。生存分析显示,SKP2、SOX10阳性表达与更差的DFS(P=0.007、P<0.001)和OS(P=0.013、P<0.001)相关,TIL高表达与更好的DFS(P=0.016)及OS(P=0.004)相关。在生物表志物的联合表达中,AR+/SKP2-、AR+/SOX10-与更好的DFS(P=0.004、P<0.001)及OS(P=0.007、P=0.001)相关,SOX10+/低TIL、PD-L1+/低TIL与更差的DFS(P<0.001、P=0.008)及OS(P=0.001、P=0.002)相关,AR-/低TIL者具有更差的OS(P=0.014)。SKP2(HR=4.143,95%CI为1.578~10.875)、SOX10(HR=7.578,95%CI为2.067~27.782)的阳性表达是影响TNBC患者DFS的独立预后因子,SKP2(HR=3.758,95%CI为1.400~10.084)、SOX10(HR=5.131,95%CI为1.316~20.000)及TIL(HR=0.375,95%CI为0.154~0.917)的阳性表达是TNBC患者OS的独立预后因子(P均<0.05)。结论:在TNBC中,AR阳性、TIL高表达与具有更好预后的临床病理特征相关,SKP2、SOX10和PD-L1与具侵袭性的临床病理特征相关。SKP2、SOX10及TIL表达与TNBC预后相关,提示这些生物指标可能成为TNBC新的预后因子,同时它们也有可能成为潜在的治疗靶点。

SENEX-mediated CDK4/6 inhibition promotes senescence and confers apoptosis resistance in B-cell non-Hodgkin lymphoma

Background:The primary cause of treatment failure in patients with refractory or relapsed B-cell non-Hodgkin lymphoma(r/r B-NHL)is resistance to current therapies,and therapy-induced senescence(TIS)stands out as a crucial mechanism contributing to tumor drug resistance.Here,we analyzed SENEX/Rho GTPase Activating Protein 18(ARHGAP18)expression and prognostic significance in doxorubicin-induced B-NHL-TIS model and r/r B-NHL patients,investigating its target in B-NHL cell senescence and the effect of combining specific inhibitors on apoptosis resistance in B-NHL-TIS cells.Methods:Raji cells were transfected with the human SENEX shRNA recombinant lentiviral vector(Sh-SENEX)and the empty vector negative(NC)to construct a stable transfection cell line with knockdown of SENEX.Effect of SENEX-silencing on B-NHL-TIS formation,cell function and cell cycle-related pathways was analyzed.Using doxorubicin(DOX)-inducible senescent B-NHL cells combined with the specific cyclin dependent kinase 4/6(CDK4/6)inhibitor Palbociclib to observe that blocking CDK4/6 effects on TIS formation.SENEX expression of 21 B-NHL patients and 8 healthy controls were analyzed by qRT-PCR,and the correlation between its expression and clinical indicators were evaluated.Results:The downregulation of SENEX expression promotes G1-S phase transition and apoptosis while inhibiting cell proliferation,collectively suppressing the formation of TIS in B-NHL.Blockade of CDK4/6 promotes the DOX-induced G1 phase arrest to enhance TIS formation in B-NHL cells which can reverse the regulatory effect of silencing SENEX on B-NHL cell cycle regulation and senescence.The expression levels of SENEX were notably elevated in B-NHL patients compared to healthy controls,and Elevated expression levels of SENEX were associated with poor prognosis of B-NHL patients.Conclusions:SENEX enhances apoptosis resistance in B-NHL by inhibiting CDK4/6,thereby preventing G1-S phase transition and promoting TIS formation.

外周血单个核细胞GTSE1水平与上皮性卵巢癌预后的相关性

目的:探究外周血单个核细胞G_(2)/S期应答相关蛋白1(G_(2)and S phase-expressed-1,GTSE1)水平与上皮性卵巢癌(epithelial ovarian cancer,EOC)预后的关系。方法:GEPIA和Kaplan-Meier Plotter分析GTSE1在卵巢癌组织中的表达及其与预后的关系。选择2017年04月至2020年10月本院126例EOC患者(EOC组)和40例同期无EOC的健康体检者(对照组)作为研究对象。Ficoll密度梯度离心法分离外周血中单个核细胞,蛋白质免疫印迹法检测GTSE1水平。Spearman相关分析EOC组织和外周血单个核细胞中GTSE1水平的关系。随访了解EOC预后,用COX回归分析EOC预后的风险因素。结果:GEPIA和Kaplan-Meier Plotter分析结果显示,卵巢癌组织中GTSE1水平高于正常卵巢组织(P<0.05),GTSE1低水平卵巢癌患者的中位无进展生存时间高于GTSE1高水平卵巢癌患者(P<0.05)。随访期间复发98例(77.8%),其中铂类敏感型65例,铂类耐药型33例;死亡41例(32.5%)。EOC组的外周血单个核细胞中GTSE1 mRNA和GTSE1蛋白水平均高于对照组(P<0.001)。EOC患者癌组织和外周血单个核细胞中GTSE1水平呈正相关关系(r_(s)=0.225,P=0.011)。国际妇产科联盟(International Federation of Gynecology and Obstetrics,FIGO)Ⅰ-Ⅱ期患者的GTSE1水平低于Ⅲ-Ⅳ期的患者(P<0.001);未复发患者的GTSE1水平低于铂类敏感型和铂类耐药型的患者(P<0.05);生存患者的GTSE1水平低于死亡患者(P<0.001)。GTSE1高水平患者的无复发生存时间和总生存时间均低于GTSE1低水平患者(P<0.001)。COX回归分析结果显示,FIGO分期高(HR=2.110,95%CI:1.465~3.038,P<0.001;HR=2.261,95%CI:1.212~4.216,P=0.011)、初次手术残存灶>1 cm(HR=1.724,95%CI:1.130~2.631,P=0.012;HR=2.465,95%CI:1.246~4.874,P=0.010)和GTSE1>1.29(HR=2.071,95%CI:1.304~3.291,P=0.002;HR=5.634,95%CI:2.410~13.169,P<0.001)是EOC预后(复发和生存)的独立危险因素,应用贝伐单抗(HR=0.293,95%CI:0.116~0.738,P=0.010;HR=0.141,95%CI:0.056~0.357,P<0.001)是EOC预后的独立保护因素。结论:EOC患者外周血单个核细胞中GTSE1水平高提示预后不良风险高。

Fe_(1-x)S-BC/g-C_(3)N_(4)的制备及其光芬顿降解盐酸四环素的性能

通过浸渍联合原位煅烧方法成功制备了Fe_(1-x)S-BC/g-C_(3)N_(4)复合光催化材料,采用SEM、XRD、FTIR和XPS对Fe_(1-x)S-BC/g-C_(3)N_(4)催化剂的结构进行表征分析,并将其用于盐酸四环素(TCH)的光芬顿催化降解,考察了三聚氰胺加入量、催化剂投加量、TCH初始浓度、H2O2浓度和初始pH对TCH降解率的影响.结果表明,最佳反应条件为pH=3.0、H2O2=10 mmol·L^(−1)、催化剂投加量为1.0 g·L^(−1),光照1 h后,Fe_(1-x)S-BC/g-C_(3)N_(4)-2对40 mg·L^(−1)的TCH降解率达到98.5%,且铁溶出量仅为0.5 mg·L^(−1).对照实验显示,Fe_(1-x)S-BC/g-C_(3)N_(4)-2的光芬顿催化反应速率常数分别是其光催化反应和非均相芬顿反应的66.6倍和2.9倍.杂离子干扰实验表明Fe_(1-x)S-BC/g-C_(3)N_(4)-2对常见的阴离子有良好的耐受性,经过5次循环使用后,TCH的解率仍有87.1%.活性物种猝灭实验证实·OH和·O2−为主要的活性物种.

Postoperative chemotherapy with S-1 plus oxaliplatin versus S-1alone in locally advanced gastric cancer(RESCUE-GC study): a protocol for a phase Ⅲ randomized controlled trial

Background： The ACTS-GC study had shown postoperative adiuvant therapy with S-1 improved survival of patients with locally advanced gastric cancer. Addition of oxaliplatin to S-1 is considered to be acceptable as one of the treatment options for gastric cancer patients after radical gastrectomy with D2 lymph node excision. Methods： We have commenced a randomized phase III trial in December 2016 to evaluate S-I plus oxaliplatin compared with S-1 alone in the adjuvant setting for locally advanced gastric cancer. A total of 564 patients will be accrued from 13 Chinese institutions in two years. The primary endpoint is 3-year relapse-free survival. The secondary endpoints are 5-year overall survival, proportion of patients who complete the postoperative chemotherapy and incidence of adverse events. Ethic and dissemination： The trial has been approved by the institutional review board of each participating institution and it was activated on December, 2016. The enrollment will be finished in December, 2018. Patient＇s follow-up will be ended until December, 2023. Trial registration： ClinicalTrials.gov, identifier： NCT02867839. Registered on August 4, 2016.

Butyrate inhibits the bovine rumen epithelial cell proliferation via downregulation of positive regulators at G0/G1 phase checkpoint

Short-chain fatty acids(SCFAs)butyrate promote the postnatal rumen epithelial development and maturation in ruminants.However,molecular mechanisms of effects of butyrate on the bovine rumen epithelial cells(BRECs)proliferation remain elusive.Therefore,purpose of this study was to investigate the effects of butyrate on the expression of genes and proteins at G0/G1 and S phase of BRECs cycle.Our results showed that BRECs treated with butyrate inhibited(P<0.05)the proliferation of BRECs,relatively to control.Flow cytometric assays revealed that butyrate triggers the BRECs cycle arrest at the G0/G1 phase.qRT-PCR analyses of mRNA level of genes involved in the G0/G1 phase of cell cycle showed that butyrate significantly upregulated(P<0.001)the expression of mRNA encoding p21^(Cip1)compared with control group,but it decreased(P<0.05)the mRNA levels of cyclin D1 and CDK4 genes at G0/G1 phase checkpoint compared with control.Moreover,Western blot also revealed that butyrate downregulated the expression of cyclin D3,CDK6,p-Rb,and E2F1 proteins involved in the modulation of G0/G1 phase of cell cycle.In conclusion,our results demonstrated that butyrate inhibits the proliferation of BRECs via downregulation of positive regulators at G0/G1 phase checkpoint.

1-Chloromethyl-6,7-dimethoxy-3,4-dihydro-1H-isoquinoline-2-sulfonic acid amide, a derivative of tetrahydroisoquinoline, induces granulocytic differentiation of the human leukemic HL-60 cells via G0/G1 phase arrest

Tetrahydroisoquinolines are known to have various biological effects, including antitumor activity. This study investigated the effect of 1-chloromethyl-6, 7-dimethoxy-3, 4-dihydro-1H-isoquinoline-2-sulfonic acid amide (CDST), a newly synthesized anticancer agent, on cellular differentiation and proliferation in HL-60 cells. Differentiation and proliferation of HL-60 cells were determined through expression of CD11b and CD14 surface antigens using flow cytometry and nitroblue tetrazolium (NBT) assay, and through analysis of cell cycle using propidium iodide staining, western blot analysis and immunoprecipitation, respectively. CDST induced the differentiation of HL-60, as shown by increased expression of differentiation surface antigen CD11b (but no significant change in CD14 expression) and increased NBT-reducing functional activity. DNA flow cytometry analysis indicated that CDST markedly induced a G0/G1 phase arrest of HL-60 cells. Subsequently, we examined the expre-ssion of G0/G1 phase cell cycle-related proteins, including cyclin-dependent kinases (CDKs), cyclins and cyclin dependent kinase inhibitors (CKIs), during the differentiation of HL-60. The levels of CDK2, CDK6, cyclin E and cyclin A were decreased, whereas steady-state levels of CDK4 and cyclin D1 were unaffected. The expression of the p27Kip1 was markedly increased by CDST, but not p21WAF1/Cip1. Moreover, CDST markedly enhanced the binding of p27Kip1 with CDK2 and CDK6, resulting in the reduced activity of both kinases. Taken together, these results demonstrate that CDST is capable of inducing cellular differentiation and growth inhibition through p27Kip1 protein-related G0/G1 phase arrest in HL-60 cells.

直角坐标系下无向双环网络G(N;±1,±s)直径的研究

提出将直角坐标系引入无向双环网络的研究,通过直角坐标系,系统研究无向双环网络G(N;±1,±s)的直径、平均直径,验证直径的下界,得出平均直径的下界。最后给出直角坐标系下无向双环网络的仿真方法,该方法克服了传统L型瓦方法在无向双环网络研究中的不足,大大提升了无向双环网络的研究水平。

阿尔茨海默病患者外周血淋巴细胞G_1S检验点功能障碍研究

目的检测G1期向S期转换的特异性阻滞剂雷帕霉素在阿尔茨海默病(Alzheimer's disease,AD)患者外周血淋巴细胞G1S检验点功能,探索AD新的外周标记物及治疗靶点。方法选择AD患者50例(AD组),另选择健康体检者50例(对照组),分离外周血淋巴细胞,经植物凝集素(促使细胞进入细胞循环)干预24h(T24期细胞),再经雷帕霉素干预24h(T48),流式细胞技术分别检测2组T24、T48细胞周期分布情况。结果在T24期细胞,AD组与对照组G1期细胞和S期细胞比较,差异无统计学意义[(71.14±5.25)%vs(71.11±4.94)%,(18.55±3.57)%vs(18.13±3.53)%,P>0.05];在T48期细胞,AD组G1期细胞明显低于对照组[(47.70±7.19)%vs(71.05±4.14)%,P=0.005)],而S期细胞明显高于对照组[(29.12±4.36)%vs(15.26±3.27)%,P=0.003)]。结论经雷帕霉素处理的AD细胞呈现不明显的G1期向S期的阻滞效应,AD患者外周血淋巴细胞G1S检验点功能障碍,G1S检验点功能障碍有望成为AD新的外周标记物及治疗靶点。

CSN3、CSN1S2和β-1g基因多态与西农萨能奶山羊产羔数的相关性研究

首次利用PCR-RFLP技术探讨κ酪蛋白(CSN3)、αs2酪蛋白(CSN1S2)和β-乳球蛋白(β-lg)基因多态与69只西农萨能奶山羊产羔数的相关性。结果表明:CSN3-TaqI位点与产羔数之间存在显著相关(P<0.05或P<0.01),如TC基因型个体第1胎产羔数高于CC型(P<0.01),CC基因型个体第2胎产羔数高于CC型(P<0.05);CSN3-HindIII位点与产羔数之间不存在关联(P>0.05);CSN1S2-Alw26I位点与产羔数间存在显著的相关性(P<0.05或P<0.01),如NF基因型个体第1胎产羔高于NN型(P<0.05),NN基因型个体第4胎产羔数高于NF型(P<0.01);β-lg-smaI位点与产羔数间不存在显著相关(P>0.05)。结果提示CSN3和CSN1S2基因对奶山羊产羔数有显著影响,从而推测酪蛋白基因可能与FecB基因连锁。因此,认为CSN3-TaqI和CSN1S2-Alw26I位点可作为奶山羊高产羔数标记辅助选择(MAS)的有效分子标记。

内皮素和心钠素调节下丘脑细胞G_1期至S期

目的观察内皮素 (ET)和心钠素 (ANP)对下丘脑胶质细胞周期素依赖蛋白激酶 (CDK)和周期素依赖蛋白激酶抑制性蛋白 (CKI)的影响。 方法采用细胞内蛋白质合成试验 (周期素D1、D3和P2 7、P57)、Northern印迹及3 H -TdR掺入试验 ,以GST -PRb和组蛋白为底物测定CDK的活性。 结果ET可增加周期素D1、D3、DNA的合成和CDK的活性 ;ANP则可逆转ET的作用 ,并增加P2 7、P57蛋白质的合成及P2 7mRNA的量。 结论ET和ANP能分别促进与抑制下丘脑细胞从G1到S期 ,从而参与细胞的增殖。

肺岩宁颗粒干预细胞周期G_1/S检测点调控信号抗Lewis肺癌细胞增殖的研究

目的观察肺岩宁颗粒对Lewis肺癌小鼠肿瘤生长、肿瘤细胞周期分布,以及G1/S检测点调控信号RB-E2F1生物轴的影响。方法采用C57BL/6小鼠,造模并随机分为6组:模型组、顺铂组、肺岩宁煎剂组(煎剂组)、肺岩宁颗粒低剂量组(低剂量组,0·3g)、肺岩宁颗粒中剂量组(中剂量组,0·6g)、肺岩宁颗粒高剂量组(高剂量组,1·2g)。造模后顺铂组1、3、5天腹腔注射顺铂0·1mg,其他各组分别灌胃给药14天,观察各组治疗后抑瘤率、瘤重、体重,流式细胞术检测细胞周期时相分布,RT-PCR测定肿瘤组织视网膜母细胞瘤蛋白(RB)-腺病毒E2启动子结合转录因子(E2F1)的mRNA表达,Western blot检测RB、E2F1蛋白表达。结果各用药组瘤重低于模型组(P<0·05,P<0·01),中剂量组体重明显高于模型组和顺铂组(P<0·05,P<0·01)。流式细胞术发现中剂量组的G0/G1比例较模型组、顺铂组和煎剂组显著增多(P<0·01),癌细胞增殖指数明显降低(P<0·01,P<0·05)。RT-PCR显示中剂量组E2F1mRNA水平明显低于模型组、顺铂组和煎剂组(P<0·01);中剂量组RBmRNA表达明显高于模型组、顺铂组和煎剂组(P<0·01)。Western blot分析显示中剂量组较模型组和顺铂组明显抑制E2F1蛋白表达(P<0·05),并较模型组、顺铂组和煎剂组明显增加RB蛋白表达(P<0·05)。结论肺岩宁颗粒抑制Lewis肺癌肿瘤生长与干预细胞周期时相分布有关,能使癌细胞较多的阻滞在细胞周期G0/G1期,通过抑制E2F1,增强RB表达,从而干预细胞周期G1/S检测点信号通路中RB-E2F1生物轴实现抗肺癌增殖。

甘蔗渣淀粉功能降解菌筛选及s2g5-1和s3g4-8的鉴定

[目的]筛选甘蔗淀粉功能降解菌,并对菌株s2g5-1和s3g4-8进行鉴定。[方法]利用多种选择性培养基,从自然发酵不同阶段的甘蔗渣中分离到多种淀粉分解菌,并对其进行初筛和复筛。[结果]获得了淀粉降解功能菌株s2g5-1和s3g4-8。通过形态、生理生化和分子综合鉴定得出s2g5-1和s3g4-8菌株均为解淀粉芽孢杆菌。[结论]该研究结果为甘蔗渣工厂化应用提供了理论依据。

UV-B辐射对拟南芥细胞周期G1/S期转变的影响

以同步化的拟南芥(Arabidopsis thaliana)根尖细胞为材料,研究了UV-B辐射对拟南芥细胞周期G1/S期转变的影响。细胞周期荧光显微图像分析表明,UV-B辐射延缓了拟南芥根尖细胞G1/S期的转变。基因表达的RT-PCR检测表明,在UV-B辐射下G1/S期转变的标志基因Histone H4和E2Fa的表达受抑制,而G1/S期转变的抑制因子KRP2基因表达则受诱导上调。单细胞凝胶电泳检测结果表明,UV-B辐射引起拟南芥根尖细胞内积累大量的环丁烷嘧啶二聚体。以上结果表明,UV-B辐射抑制植物的生长可能受细胞周期和DNA损伤调控。

双优无向双环网络G(N;±1,±s)分布特性研究

基于直角坐标系研究一类在一族无向双环网络G(N;±1,±s)(1<s<N)中直径、平均距离均达到最小值的双优双环网络DG(N;±1,±s)的仿真图形特征及其分布特性,计算出4≤N≤1 000中任意N存在的双优双环网络个数n;仿真出4≤N≤1 000的n-N紧优分布图并列出为紧优,但不存在双优双环网络的N值,发现n-N分布呈现平稳的波动特性,n不随着N递增。

有氧运动对大鼠外周血EPCs G_1/S转换信号通路相关基因mRNA表达的影响

目的:研究有氧运动对EPCs细胞周期关键转换点G1/S转换信号通路相关基因mRNA表达的影响,从分子水平探讨有氧运动影响外周血EPCs增殖的机制。方法:两月龄雄性SD大鼠20只,按体重分层随机分为空白对照组和有氧运动组.。采用递增负荷跑台运动,每天训练1次,每周6天,由15 m/min(持续25 min)递增至26 m/min(持续50 min),跑台坡度为10%,共训练8周。运动方案结束后,采集大鼠外周血得到单个核细胞并诱导其分化获取EPCs,培养12天后收集贴壁EPCs进行全基因组检测,检测结果采用GeneSpring11.0芯片软件进行分析,对运动组与对照组相比差异表达基因进行信号通路分析。运动组/对照组基因差异表达倍数大于2倍视为表达具有差异,且表达上调;对照组/运动组基因差异表达倍数大于2倍视为表达具有差异,且表达下调。结果:在G1/S转换信号通路的10个相关基因中,Fbxo5 mRNA、Ccne1 mRNA、Orc1lmRNA、Dhfr mRNA、Pola1 mRNA、Pcna mRNA表达上调,Tyms mRNA、Cdc45l mRNA、Cdc6mRNA、Cdt1 mRNA无明显改变。结论:有氧运动可通过改变EPCs细胞周期G1/S转换相关基因Fbxo5、Ccne1、Orc1l、Dhfr、Pola1、Pcna mRNA表达,促使细胞增殖的关键点由DNA合成前期向DNA合成期转化,并为DNA的复制做充分准备,有利于EPCs细胞周期的缩短。

流体切应力促成骨细胞通过细胞周期G1/S调控点机制的研究

[目的]探讨流体切应力(FSS)促成骨细胞增殖、分化作用与细胞周期从G1期向S期转化机制的关系,为确立最佳生理应力刺激骨再生提供依据。[方法]从KM乳鼠颅盖骨提取原代成骨细胞,在体外流体小室内分别受FSS(12dyn/cm2)作用0、0.25、0.5、1、2、4h,通过MTT法分析细胞增殖能力,并利用碱性磷酸酶(ALP)的表达评价其分化能力;通过流式细胞仪、免疫荧光染色和RT-PCR测定细胞周期G1/S百分比、细胞周期依赖激酶2和4(CDK2、CDK4)的活性改变及E2F1、p27mRNA的表达实现FSS促成骨细胞由G1期转向S期的测定。[结果]FSS促增殖作用在短期(0.25h、0.5h)明显,并且细胞生长曲线前移;但在1、2、4h却有明显抑制增殖作用。FSS同样增加了ALP的活性,尤其在应力作用0.25、0.5h时显著(比对照达128%和158%);而应力作用1、2、4h后减低了ALP的表达。在FSS作用1h内细胞周期S期百分比增高,作用0.5h后与对照组比较明显增高(P<0.05);但随着时间的增加细胞周期S期百分比开始下降,当作用时间持续4h后S期百分比下降明显(P<0.05)。流体切应力增加了活化pRb的CDK2、CDK4的活性,而且与CDK2相关的E2F1表达量也明显增加;而细胞周期依赖激酶抑制剂p27在流体切应力作用下有所下降。其中流体切应力在0.25h、0.5h明显增加了E2FlmRNA的表达水平(P<0.05),此效应在作用1h后减退。[结论]适宜的流体切应力通过上调CDK2、CDK4及E2F1,下调p27,使细胞从G1期转化到S期,在流体切应力促成骨细胞增殖、分化机制中起重要作用;并且这种作用有明显的FSS作用时间限制性。

最优无向双环网络G(N;±1,±s)的构造

创造性地将直角坐标系引入无向双环网络的研究,通过直角坐标系,系统研究无向双环网络G(N;±1,±s)的仿真图形,提出最优无向双环网络BestG(N;±1,±s)(直径、平均直径均达到下界)的构造方法并研究步长s和其直径之间的关系。与传统L型瓦方法在无向双环网络研究中相比,该方法克服其不足,大大提升了无向双环网络的研究水平,相关研究在国内外文献中尚未见到。