沉默TRIM23基因抑制骨肉瘤细胞的增殖

目的 探讨TRIM23基因对骨肉瘤细胞增殖能力的影响.方法 应用Western blot实验检测TRIM23基因在骨肉瘤细胞中的表达;应用shRNA质粒转染骨肉瘤细胞系U2OS,通过MTT与平板克隆形成实验评估细胞增殖能力;应用Westernblot实验检测U2OS细胞Akt/P53/P21通路的表达改变.结果 TRIM23蛋白在骨肉瘤细胞中的表达高于成骨细胞;沉默TRIM23基因可以抑制骨肉瘤细胞的增殖能力;沉默TRIM23基因下调P-Akt表达,但总Akt的表达无明显改变,上调P53与P21的表达.结论 TRIM23在骨肉瘤细胞中表达升高,TRIM23能通过调节Akt/P53/P21通路影响骨肉瘤细胞的增殖.     

CISD2在乳腺癌组织中的表达及其对人乳腺癌MCF-7细胞增殖与侵袭的影响

目的检测CDGSH铁硫结构域2 (CDGSH iron sulfur domain 2, CISD2)在乳腺癌组织中的表达及其对人乳腺癌MCF-7细胞增殖与侵袭的影响。方法选取46乳腺癌组织及10例对应的癌旁正常组织,免疫组织化学方法与Western blot方法检测乳腺癌和癌旁组织中CISD2蛋白的表达。应用化学合成小干扰RNA技术沉默人乳腺癌MCF-7细胞中CISD2基因的表达,Western blot实验验证基因沉默效率。采用CCK-8和克隆形成实验检测转染后MCF-7细胞的增殖和侵袭情况。结果与癌旁正常组织相比,乳腺癌组织中CISD2蛋白表达的平均光密度值明显上调, siRNA能够明显抑制人乳腺癌MCF-7细胞CISD2的表达。CISD2基因沉默后,人乳腺癌MCF-7细胞的增殖能力和侵袭能力显著降低,P0.01。结论 CISD2可能是治疗乳腺癌的潜在靶点。     

沉默HAX1基因对人骨肉瘤细胞凋亡的影响

目的观察HS1相关蛋白X-1(HS1-associated protein X-1,HAX1)对骨肉瘤细胞凋亡的影响。方法应用基因沉默技术在骨肉瘤细胞系MG63中下调HAX1基因的表达,并且通过Western blot实验与免疫荧光实验检测基因沉默效率;应用MTT方法及克隆形成实验,评价沉默HAX1基因对MG63细胞增殖能力的影响;流式细胞术检测细胞凋亡并通过Western blot实验检测下游蛋白的表达变化。结果沉默HAX1基因抑制人骨肉瘤细胞系MG63的增殖能力与克隆形成能力,流式细胞技术显示沉默HAX1可以诱导MG63细胞凋亡,Western blot实验说明HAX1诱导的MG63细胞凋亡与caspase3和caspase9蛋白上调相关。结论 HAX1可能是维持骨肉瘤细胞增殖能力的关键基因,沉默该基因诱导骨肉瘤细胞凋亡可能与caspase3/caspase9上调相关。     

siRNA 沉默NOK 基因抑制脑胶质瘤U251 细胞增殖与侵袭

目的:通过小干扰RNA(siRNA)沉默NOK基因的转录表达,研究NOK基因在人脑胶质瘤细胞U251增殖、凋亡及侵袭中的调控作用。方法:合成NOK siRNA(si-578和si-996),脂质体转染U251细胞,qRT-PCR、Western blot检测其对NOK基因转录及表达的抑制效果,MTS法及平板克隆形成实验研究其对细胞增殖的影响,Transwell试验检测细胞迁移能力,Annexin V-FITC/7-AAD双染法检测细胞凋亡,Western blot检测Cyclin D1及AKT的蛋白表达。结果:si-578和si-996可显著降低NOK基因转录和表达(P0.05)。抑制U251细胞NOK基因表达,可显著抑制细胞增殖和侵袭(P0.05),凋亡细胞数量明显增加(P0.05),G_1期U251细胞数量显著增加(P0.05),S期细胞明显减少(P0.05),Cyclin D1表达和AKT磷酸化水平明显降低。结论:NOK在脑胶质瘤细胞的增殖、侵袭和凋亡过程中发挥重要调节作用。     

沉默Cat D对骨肉瘤细胞增殖、凋亡和侵袭的影响及相关信号通路

研究组织蛋白酶D(cathepsin D,Cat D)在骨肉瘤细胞中的表达，并通过shRNA技术沉默Cat D,探讨该分子对骨肉瘤细胞MG63和U2OS增殖、凋亡及侵袭的作用和机制。构建sh-Cat D质粒及阴性对照质粒sh-NC并转染至骨肉瘤细胞MG63和U2OS中，RT-PCR和Western blotting检测Cat D在骨肉瘤细胞中的表达；CCK-8法、克隆形成实验和EdU荧光染色实验检测骨肉瘤细胞的增殖活性；Transwell实验检测肿瘤细胞的侵袭能力；FACS检测肿瘤细胞的凋亡情况；Western blotting检测细胞凋亡相关蛋白(Bax和Bcl-2)的表达及Akt/mTOR信号通路相关蛋白(Akt和mTOR)的磷酸化水平。结果显示，相较健康人成骨细胞hFOB,Cat D在骨肉瘤细胞中的表达显著升高，尤其是MG63和U2OS细胞中Cat D的高表达均显著(均P<0.001)。与sh-NC组相比，Cat D沉默显著抑制MG63和U2OS细胞的增殖和侵袭(均P<0.001)。与sh-NC组相比，Cat D沉默通过上调Bax表达和下调Bcl-2表达促进肿瘤细胞的...     

分化抑制因子Idl对骨肉瘤细胞增殖的影响

目的探讨分化抑制因子Idl对骨肉瘤细胞增殖的影响及可能的途径。方法采用四甲基偶氮唑蓝（MTY）法检测Idl表达调节后MG．63细胞增殖变化情况;采用流式细胞术检测Idl下调表达后,MG．63细胞凋亡及细胞周期变化情况;Westemblotting技术检测Idl下调表达后对p-AKT水平的影响。结果本实验利用RNA干扰技术下调骨肉瘤细胞系Idl表达后,可以明显抑制MG．63细胞的增殖,p-AKT的水平也显示下降,流式细胞术证明下调后Idl的水平可以一定程度地调节细胞凋亡水平,而对细胞周期无明显影响,另外进一步构建了Idl的真核表达质粒,转染Idl过表达质粒后。并未见骨肉瘤细胞明显地增殖加速。结论分化抑制因子Idl可能通过影响AKT信号通路进而影响了骨肉瘤细胞的增殖。     

下调HMGA2基因表达对改善骨肉瘤U2OS细胞恶性表型的实验研究

目的:研究HMGA2表达在维持人骨肉瘤U2OS细胞恶性表型中的作用,为基因靶向治疗提供理论依据。方法:采用基于DNA的shRNA表达载体HMGA2-shRNA,稳定转染人骨肉瘤U2OS细胞,下调其HMGA2表达水平,并应用RT-PCR技术检测其对HMGA2基因的沉默效果;经Cell Counting Kit-8(CCK8)测定、Hoechst33342染色荧光显微镜观察及Boyden小室法分别检测细胞增殖、凋亡及迁移情况;实时定量RT-PCR检测mRNAs表达水平。结果:稳定转染靶向HMGA2的shRNA可特异性下调U2OS细胞HMGA2 mRNA表达水平;其作用结果使细胞的增殖和迁移能力受到明显抑制,自发凋亡率及Caspase 3和Caspas 9基因表达水平显著升高。结论:HMGA2基因异常表达在维持人骨肉瘤U2OS细胞恶性表型中起重要作用,靶向HM-GA2的基因治疗可能为骨肉瘤治疗带来新希望。     

RNA干扰环指蛋白2基因抑制胰腺癌细胞系PANC-1增殖和迁移

目的研究沉默环指蛋白2(RNF2)基因对人胰腺癌细胞系PANC-1增殖、迁移、周期和凋亡的影响及可能机制。方法用siRNA-RNF2转染PANC-1细胞沉默RNF2表达,同时设立转染无义序列(siRNA-NC)的空转染组及不进行任何处理的空白对照组(mock)。荧光定量PCR检测RNF2 mRNA表达;Western blot检测RNF2和p53表达;MTS实验和划痕实验分别检测细胞增殖和迁移能力;流式细胞计量术检测细胞转染率、凋亡率和细胞周期。结果相比正常胰腺导管上皮细胞,RNF2在胰腺癌细胞系中高表达(P<0.05)。转染siRNA-RNF2的PANC-1细胞与阴性对照组比较,RNF2 mRNA及蛋白表达下调;细胞增殖被抑制(P<0.05);细胞迁移能力下降(P<0.05);细胞凋亡率增高(P<0.05);G_0/G_1期细胞比例上升,S期和G2/M期细胞比例则降低(P<0.05)。此外,转染siRNA-RNF2显著下调PANC-1细胞中p53蛋白的表达。结论 siRNA-RNF2特异性下调胰腺癌细胞RNF2表达,显著抑制细胞增殖和迁移,结果提示RNF2可能成为胰腺癌基因治疗的一个新靶点。     

下调DPT基因通过调节CyclinD1抑制食道癌细胞的增殖

目的观察皮肤桥蛋白(Dermatopontin, DPT)对食道癌细胞增殖能力的影响。方法应用基因沉默技术在食道癌细胞Eca-109中下调DPT基因的表达,通过Western blot实验与免疫荧光实验评价24h、48h、72h基因沉默效率;应用克隆形成实验及MTT实验,检测下调DPT基因对食道癌细胞增殖能力的影响;流式细胞术检测细胞周期;通过Western blot实验检测CyclinD1蛋白的表达变化。结果抑制DPT基因可以下调人食道癌细胞的克隆形成与细胞增殖能力,沉默DPT基因引起食道癌细胞G 0/G1期阻滞, CyclinD1蛋白表达下调。结论 DPT参与食道癌的发病机制,是食道癌治疗的新靶点。     

RNA干扰组蛋白去乙酰化酶4诱导骨肉瘤细胞凋亡

目的探讨沉默组蛋白去乙酰化酶4(HDAC4)对骨肉瘤细胞HOS,U2OS生物学行为的影响。方法用脂质体瞬时转染法将化学合成HDAC4-siRNA转染至骨肉瘤HOS及U2OS细胞中,实时荧光定量PCR(q-PCR)法检测细胞中HDAC4 mRNA的表达;蛋白质免疫印迹法(Western blot)检测细胞HDAC4及其下游基因HIF-1α的蛋白表达;CCK-8法检测细胞的增殖能力;流式细胞仪检测细胞凋亡;Transwell小室法检测细胞的侵袭能力。结果转染后HOS及U2OS细胞中HDAC4 mRNA表达明显降低(P0.01)。沉默HDAC4后HOS细胞早期凋亡率为(16.8±2.1)%,较si-control组(10.2±2.5)%明显增加(P0.05);U2OS细胞早期凋亡率为(21.4±3.1)%,较si-control组(12.5±2.3)%明显增加(P0.05);HOS细胞si-con组及si-HDAC4组细胞的穿膜细胞数分别为(146±34)个、(45±20)个,U2OS细胞为(207±35)个、(121±23)个,分别显著低于si-con组(P0.05)。si-HDAC4能够明显降低HDAC4以及下游基因HIF-1α的表达。结论针对HDAC4基因的特异性RNA小干扰片段能够下调HDAC4mRNA及蛋白的表达,并抑制骨肉瘤细胞的增殖和侵袭,诱导细胞凋亡。     

An apparent KIR2DS2-negative KIR2DL2-positive genotype discloses the novel allele KIR2DS2*00104

KIR2DS2*00104 lacks a distinctive synonymous substitution of KIR2DS2 in nucleotide 418 that affects KIR genotyping.     

CaO-MgO-P_2O_5-SiO_2-CaF_2系统自硬性玻璃的研究

为研究钙离子、镁离子在体内环境中对自硬性玻璃结晶行为的影响,为自硬性生物活性玻璃的临床应用提供依据,本文设计了CaO-P2O5-SiO2-CaF2(Ca-glass)和CaO-MgO-P2O5-SiO2-CaF2(CaMg-glass)系统玻璃并使用模拟体液(simulated body flu id,SBF)进行了研究。首先采用磷酸氢二氨[(NH4)2HPO4]/[NH4H2PO4]硬化液与Ca-glass、CaMg-glass制成硬化体,然后使用X射线衍射(XRD)、扫描电镜(SEM)、失重、力学分析等方法,研究硬化体在SBF中的结晶性、降解性和力学性能。实验结果表明,玻璃粉末与磷酸铵缓冲溶液反应形成了磷酸铵钙[(NH4)2.Ca(HPO4)2.H2O]硬化体。硬化体经过SBF浸泡,Ca-glass系统硬化体中部分磷酸铵钙转化成羟基磷灰石,而CaMg-glass系统硬化体仍然为磷酸铵钙。Ca-glass与CaMg-glass硬化体在SBF中浸泡28天分别降解19.4%和31.3%,抗压强度分别为93.14MPa和64.52MPa。镁离子的歧化作用是导致Ca-glass、CaMg-glass硬化体结晶性能、降解性能以及力学性能差别的主要原因。     

K2O-B2O3-Al2O3-SiO2-MgO-F系统可切削生物微晶玻璃

目的 可切削微晶玻璃的制备温度高达1500 ℃以上,此特性严重制约其产业化发展.本文设计制备了K2O-B2O3-Al2O3-SiO2-MgO-F系统低温云母生物微晶玻璃,并探讨制备工艺对材料结构和性能的影响.方法 采用1300 ℃熔化工艺与600～750 ℃晶化热处理工艺制备微晶玻璃,通过X射线衍射分析方法研究微晶玻璃的晶相组成,利用扫描电子显微镜观察微晶玻璃的形貌,并通过显微硬度分析、高速砂轮切削实验考察微晶玻璃的可切削性能.结果 分别经过600 ℃、650 ℃、700 ℃、750 ℃晶化热处理2 h、4 h、8 h后,玻璃中均形成了主晶相为氟金云母的微晶玻璃,微晶玻璃的显微硬度为3～8 GPa.且随着晶化温度的升高,微晶玻璃层状结构逐渐明晰,但硬度不断下降,其可切削性持续提高.结论 低温下熔化K2O-B2O3-Al2O3-SiO2-MgO系统玻璃工艺降低了可切削微晶玻璃的制备温度和成本,利于产业化生产和推广应用.     

Cross-Protection in Mice After Immunization with H2N2, H3N2, and Heq2Neq2 Influenza Virus Strains

Mice were vaccinated with the influenza viruses A/Japan/57 (H2N2), A/Hong Kong/68 (H3N2), and A/Equi/Miami/63 (Heq2Neq2) and the hemagglutinin and neuraminidase recombinants derived from these viruses. After infection with the parent viruses, protection was compared with serological findings. It was found that influenza vaccine protects not only against infection with a strain identical or closely related to the vaccine strain, but against heterologous strains as well. Vaccination with Hong Kong/68 and its neuraminidase recombinant resulted in a heterologous neuraminidase inhibition titer against Japan/57 and in a protection against infection with Japan/57. By contrast, after vaccination with Japan/57 and its neuraminidase recombinant, no relevant heterologous neuraminidase inhibition titer against Hong Kong/68 was observed, whereas a protection against infection with Hong Kong/68 did exist. A cross-protection between Hong Kong/68 and Miami/63, but no relationship in the hemagglutination or neuraminidase inhibition tests, was established in the preinfection sera. A one-way antigenic relationship between these viruses was confirmed by the rise of hemagglutinin or neuraminidase antibodies against Hong Kong/68 in the postinfection sera. No cross-protection or serological relationship existed between Miami/63 and Japan/57. Besides the hemagglutinin and neuraminidase, a third factor, the “mouse-protecting antigen,” was considered to contribute to the protection obtained. According to the protection observed, the mouse-protecting antigen of Hong Kong/68 virus is related to that of Japan/57 as well as Miami/63 virus. The mouse-protecting antigens of both Japan/57 and Miami/63 are related to that of Hong Kong/68.     

2-Perbromomethyl-2-oxazoline: a novel trifunctional initiator for the ring-opening polymerization of 2-methyl-2-oxazoline

Polymerization of 2-methyl-2-oxazoline was carried out using a trifunctional initiator, 2-perbromomethyl-2-oxazoline. The degree of polymerization (DP) of the resulting polymer was very close to the feed mole ratio of the monomer to initiator. The number-average molecular weight M?_n increased linearly with conversion, indicating the living nature of the propagating chain end. ¹H NMR and end-group analyses results are consistent with the proposal that the polymer possesses a star-shaped structure.     

H2O2 enhances Ca2+ release from osteoblast internal stores

The physiological activity of osteoblasts is known to be closely related to increased intracellular Ca2+ activity ([Ca2+]i) in osteoblasts. The cellular regulation of [Ca2+]i in osteoblasts is mediated by Ca2+ movements associated with Ca2+ release from intracellular Ca2+ stores, and transmembrane Ca2+ influx via Na+-Ca2+ exchanger, and Ca2+ ATPase. Reactive oxygen species, such as H2O2, play an important role in the regulation of cellular functions, and act as signaling molecules or toxins in cells. In this study, we investigated the effects of H2O2 on cellular Ca2+ regulation in osteoblasts by measuring intracellular Ca2+ activities using cellular calcium imaging techniques. Osteoblasts were isolated from the femurs and tibias of neonatal rats, and cultured for 7 days. The cultured osteoblasts were loaded with a Ca2+-sensitive fluorescent dye, Fura-2, and fluorescence images were monitored using a cooled CCD camera, and subsequently analyzed using image analyzing software. The results obtained are as follows: (1) The osteoblasts with lower basal Ca2+ activities yielded a transient Ca2+ increase, a Ca2+ spike, while osteoblasts with higher basal Ca2+ activities showed a continuous increase in [Ca2+]i leading to cell death. (2) Ca2+ spikes, generated after removing Na+ from superfusing solutions, were blocked by H2O2 and this was followed by a sustained increase in Ca2+ activity. (3) ATP- induced Ca2+ spikes were inhibited by pretreating with H2O2 and this was followed by a continuous increase of [Ca2+]i. When cells were pretreated with the exogenous nitric oxide (NO) donor S-Nitroso-N-acetylpenicilance (SNAP, 50 microM), treatments of ATP (1 mM) induced a Ca2+ spike-like increase, but [Ca2+]i did not return to the basal level. (4) The expression of inositol- 1,4,5-triphosphate receptor (IP3R) was enhanced by H2O2. Our results suggest that H2O2 modulates intracellular Ca2+ activity in osteoblasts by increasing Ca2+ release from the intracellular Ca2+ stores.     

13C NMR spectroscopy of 2-formamido-2-methylpropyl acrylate and poly(2-formamido-2-methylpropyl acrylate)

The synthesis and characterization of 2-formamido-2-methylpropyl acrylate (FMPA) is reported. ¹³C NMR spectra of FMPA in CDCl₃, CD₃OD, DMSO-d₆, DMF-d₇, and D₂O exhibit two pairs of lines for all seven carbon atoms at room temperature; the ratio of the two conformers varies moderately with solvent (21 : 79 to 41 : 59). The conformers are believed to involve strong internal hydrogen bonding which is not completely broken even by the addition of trifluoroacetic acid to CDCl₃ (1/1, v/v). However, the pairs of lines coalesce in turn as the temperature is raised to 120°C in DMSO-d₆. FMPA was polymerized at 35°C in DMF and CHCl₃, using a free radical initiator and the polymer was characterized by ¹³C NMR spectroscopy.     

KIR2DL2/S2 and KIR2DS5 in alcoholic cirrhotic patients undergoing liver transplantation

IntroductionThe molecular mechanisms underlying alcoholic liver fibrosis and cirrhosis are not completely understood. Hepatic fibrosis involves the interplay of diverse cells and factors, including hepatic stellate cells (HSCs), Kupffer, NK cells, and T-lymphocyte subsets. Killer-cell immunoglobulin-like receptors (KIR) are membrane receptors involved in mediation between NK and activated HSCs, regulating NK cell function through their interaction with HLA-I molecules. The aim of this study was to analyse the genetic association between KIR genes and the susceptibility to or protection from alcoholic cirrhosis (AC) in a cohort of male AC patients undergoing liver transplantation (LT) with and without concomitant viral infections.Material and methodsKIR genotyping was performed in nuclear DNA extracted from 281 AC patients and compared with 319 male controls.ResultsSignificant differences between total AC patients and healthy controls were only found in the case of KIR2DL2 and KIR2DS5. KIR2DL2 was significantly underrepresented in non-viral AC patients (52.6% vs. 63.3%; p = 0.015), while patients heterozygous for KIR2DL2 were also underrepresented in the non-viral AC group compared with controls (p = 0.034). KIR2DS5 was overrepresented in this group compared with healthy controls (p = 0.002). All these observations were only evident in AC patients older than 54 years old.ConclusionsOur data suggest a contrary effect of KIR2DL2 and KIR2DS5 in AC patients older than 54 years, in whom the presence of KIR2DL2 appears to be protective against AC, whereas the presence of KIR2DS5 seems to promote the fibrotic process, particularly in patients with no associated viral infection.     

ExspiratorischepO2-undpCO2-Kurven bei Atmung von N2-, He- und Ar−O2-Gemischen

Zusammenfassung Zur Untersuchung der intrapulmonalen Gasmischung wurden an zehn Versuchspersonen die exspiratorischenpO₂- undpCO₂-Kurven fortlaufend und simultan massenspektrometrisch in Abhängigkeit vom Atemvolumen bei Atmung von Stickstoff-Sauerstoff-, Helium-Sauerstoff- und Argon-Sauerstoff-Gemischen registriert.Im Mischluftanteil wurden für den Abfall despO₂ von 75% auf 25% der Endamplitude im Mittel bei N₂–O₂-Atmung 81,6 ml, bei He–O₂-Atmung 66,1 ml und bei Ar–O₂-Atmung 71,9 ml benötigt. Die entsprechenden Zahlen für den Anstieg despCO₂ sind bei Atmung von N₂–O₂ 84,9 ml, von He–O₂ 68,5 ml und von Ar–O₂ 80.6 ml.DerpO₂ des Alveolarluftanteils sank während der letzten 300 ml Exspirationsvolumen bei Atmung des N₂–O₂-Gemisches im Mittel um 4,7 Torr, bei He–O₂ um 3,4 Torr und bei Ar–O₂ um 6,8 Torr. DerpCO₂ stieg gleichzeitig im Mittel bei Atmung des N₂–O₂-Gemisches um 2,8 Torr, bei He–O₂ um 2,1 Torr und bei Ar–O₂ um 3,7 Torr.Die Ursachen dieser Differenzen werden für den Mischluftanteil auf unterschiedliche Diffusions- und Strömungsbedingungen in den zentralen Lungenabschnitten zurückgeführt. Demgegenüber lassen sich die unterschiedlichen Partialdruckänderungen im Alveolarplateau durch Diffusion in den peripheren Lungenabschnitten und durch die Form der O₂ und CO₂-Bindungskurven erklären.Mit finanzieller Unterstützung der Europäischen Gemeinschaft für Kohle und Stahl durchgeführte Forschungsarbeit.