两种粒径量子点在人舌鳞癌细胞中双色荧光成像的应用研究

目的 研究粒径655 nm和525nm的两种量子点(quantum dots,QDs)对人舌癌Tca8113细胞内2种热休克蛋白( heat shock protein,HSP)进行特异性荧光标记的成像效果和稳定性,为今后的连续动态观察提供实验依据.方法利用QD655nm和QD525nm,对人舌癌Tca8113细胞内HSP90蛋白和HSP70蛋白进行特异性双重荧光标记,激光连续照射2420391 ms,在共聚焦显微镜下同时观测人舌癌Tca8113细胞内的HSP90蛋白和HSP70蛋白表达及分布,用软件Leica Confocal Software测量量子点QD655nm和QD525nm的荧光信号强度变化.结果 激光共聚焦显微镜下可见人舌癌Tca8113细胞内HSP90蛋白和HSP70蛋白均有明显表达,分别表现为红色和绿色荧光,两种蛋白重叠处呈黄色荧光,在激光连续照射中,两种荧光有所衰减,其中QD655nm的荧光强度值下降相对较快、幅度相对较大.结论 量子点荧光标记技术能同时对人舌鳞癌细胞中HSP90蛋白和HSP70蛋白进行双重标记,而且QD655nm与QD525nm都具有较强的光稳定性,均可用于蛋白的长时间动态监测,其中QD525nm的稳定性更好.     

量子点荧光成像技术在人舌鳞癌细胞缺氧环境下的应用研究

目的：利用量子点(quantum dots, QDs)荧光成像技术对氯化钴（CoCl2）诱导的缺氧环境下人舌鳞癌Tca8113细胞内Heat Shock Protein 70(HSP70)蛋白进行长时间动态连续观测。方法：对人舌鳞癌Tca8113细胞分别进行常氧培养和CoCl2模拟缺氧培养,利用QDs对细胞内HSP70蛋白进行特异性荧光标记,在激光共聚焦显微镜下观测HSP70表达及细胞内分布情况。用Image-Pro Plus软件测量缺氧0 h、6 h、12 h、24 h、36 h、48 h后HSP70蛋白的荧光信号强度变化。结果：激光共聚焦显微镜下可见人舌癌Tca8113细胞内HSP70蛋白明显表达,表现为绿色荧光。缺氧6 h后Tca8113细胞进入有丝分裂期的细胞明显增多,细胞内hsp70的表达开始增强,约在24 h时到达快速增强期,36 h组、48 h组则未见明显的进一步增强。结论：缺氧环境下Tca8113细胞有丝分裂活动明显增强,HSP70蛋白呈现出高表达,缺氧24 h时HSP70蛋白的表达达到快速增强期,随着缺氧时间的进一步延长,进入缓慢增强的平台期。     

口腔鳞癌细胞中bcl-2、bax的量子点双标免疫荧光成像研究

目的:利用量子点对口腔鳞癌细胞内bcl-2、bax蛋白进行双标免疫荧光成像研究。方法:利用量子点QD605和QD545通过双标免疫荧光法,在激光共聚焦显微镜下对人舌癌Tca8113细胞内bcl-2、bax蛋白同时观察识别。结果:不同粒径量子点可同时对舌癌细胞bcl-2、bax蛋白特异性识别,在激光共聚焦显微镜下观察到舌癌细胞bcl-2和bax蛋白高表达。QD605标记的bcl-2蛋白表现为红色荧光,QD545标记的bax蛋白表现为绿色荧光,2种蛋白在细胞内同一位置重叠呈现黄色荧光。激光连续照射1 h,3种颜色的荧光均未明显衰减。结论:量子点能同时对细胞内的2种蛋白进行双标免疫荧光成像。     

HSP70多肽复合物介导的细胞毒性T淋巴细胞对Tca8113细胞的免疫杀伤作用

目的:研究HSP70多肽(HSP70 peptide complexes,HSP70-PC)对人脾细胞毒T淋巴细胞(CTL)活性及功能的影响.方法:人舌癌Tca8113细胞在43℃条件下加热30min,恢复12h后,用亲和层析方法提纯HSP70多肽,并用Western印迹鉴定;将提纯的HSP70多肽体外刺激人脾淋巴细胞扩增、活化,然后用MTT法测定其对舌癌Tca8113细胞的杀伤作用,并用电镜和相差显微镜观察其培养上清舌癌Tca8113细胞的形态学变化.采用SPSS11.0软件包对数据进行t检验.结果:1g湿重的肿瘤细胞可提取纯化HSP70蛋白85μg,通过SDS-PAGE和Western印迹证实为HSP70抗原肽复合物;提取舌癌Tca8113细胞的HSP70-PC与体外免疫扩增的人脾淋巴细胞形成致敏CTL,当致敏CTL与Tca8113细胞效靶比为100:1和50:1时,致敏CTL的杀伤率分别为(77.4±2.9)%和(78.9±1.9)%,2组间无显著差异(P>0.05).HSP70诱导的CTL对Tca8113的杀伤率与非抗原刺激的淋巴细胞组比较,有显著性差异(P<0.01),受攻击的舌癌Tca8113细胞出现凋亡的形态学变化.结论:Tca8113细胞来源的HSP70多肽具有较强的刺激T淋巴细胞增殖的能力,能刺激人脾淋巴细胞产生特异性杀伤肿瘤细胞的效应,并能介导肿瘤细胞凋亡.     

姜黄素对人舌鳞癌Tca8113细胞形态学的影响

目的 探讨姜黄素对体外培养人舌鳞癌Tca8113细胞凋亡的形态学影响.方法 以30、40、50 μmol/L的姜黄素溶液处理体外培养的人舌鳞癌Tca8113细胞,倒置显微镜下观察细胞生长状态,吖啶橙荧光染色和透射电镜观察细胞形态学变化.结果 倒置显微镜下可观察到细胞皱缩成圆形,核染色质浓集呈球形;激光共聚焦显微镜(吖啶橙染色)可见凋亡细胞的多种形态学改变;透射电镜见核染色质浓缩并沿核膜排列,可见凋亡小体.结论 姜黄素作用于人舌鳞癌Tca8113细胞后可出现细胞凋亡的形态学改变.     

MHC-Ⅰ类链相关基因A真核表达载体的构建及稳定转染舌鳞癌细胞的实验研究

采用PCR技术扩增pCMV-SPORT6-MICA中编码MICA基因的cDNA序列,重组至有绿色荧光蛋白标记的真核表达载体pEGFP-N1,构建最终的表达载体pEGFP-N1-MICA,脂质体法转染Tca8113-Tb细胞,G418筛选,荧光显微镜下观察绿色荧光蛋白的表达,有限稀释法建立稳定过表达MI-CA基因的Tca8113-Tb细胞系,RT-PCR、real time PCR和免疫细胞化学检测MICA在该细胞中的表达。     

量子点对口腔鳞癌Tca8113活细胞中bcl-2、bax的荧光标记观察

目的:探讨量子点对口腔鳞癌(OSCC)活细胞bcl-2、bax蛋白进行观察研究。方法:量子点QD605,QD545通过间接免疫荧光法,在激光共聚焦显微镜下观测人舌癌Tca8113活细胞内bcl-2、bax蛋白与量子点孵育0.5 h、1.0h、1.5 h和2.0 h的荧光成像。结果:量子点对OSCC活细胞中的bcl-2、bax蛋白的观察研究显示:在0.5 h～2.0 h时,QD605和QD545与bcl-2、bax蛋白结合,荧光从分布于胞浆边缘逐渐至胞浆。结论:量子点能对活细胞内蛋白进行观察。     

PAMAM-D介导EGFP基因转染人舌鳞癌细胞的实验研究

目的:优化聚酰胺-胺型树枝状高聚物(PAMAM-D)纳米载体介导增强型绿色荧光蛋白(EGFP)基因转染人舌鳞癌Tca8113细胞的条件,以获得最佳的转染效率和细胞内表达。方法:采用不同的质粒DNA浓度、PAMAM-D代数、PAMAM-D∶DNA质量比以及转染时间等参数,在激光共聚焦显微镜下,观察PAMAM-D介导pEGFP-N1体外转染Tca8113细胞,检测转染效率,并应用单因素方差分析等统计学方法进行比较分析;结合细胞生长和荧光蛋白的表达情况,进一步评估和优化转染条件。结果:1.0μg质粒DNA与2.0μlG5PAMAM-D形成复合物,转染细胞2h后,可获得最佳的转染效率(42.1%);G5PAMAM-D转染效率显著高于G2PAMAM-D(42.1%比19.4%,P<0.05);PAMAM-D基因转移系统对细胞的生长增殖无显著影响(P>0.05)。结论:PAMAM-D纳米载体在优化的转染条件下,可安全高效地介导目的基因转染Tca8113细胞,是一种较理想的基因转移系统。     

热休克诱导人舌鳞癌Tca8113细胞HSP70表达的研究

目的:研究热休克恢复期人舌癌Tca8113细胞热休克蛋白(HSP70)的表达和热动力学变化,为人舌鳞癌的免疫治疗提供理论基础。方法:通过人舌鳞癌细胞Tca8113在43℃加热30min,运用免疫组化和流式细胞技术检测在各时间点细胞HSP70的表达,各时间点再次以相同条件加热后用MTT法测各组细胞活性,以期了解Tca8113细胞HSP70表达的动态变化。结果:热休克后恢复2h即出现HSP70的表达,8~12h达到高峰,之后逐渐减少,48h后基本恢复至加热2h后的水平,热休克后恢复12h细胞活性最强。结论:HSP70的迅速表达与缓慢降解对维持Tca8113细胞的生理功能有重要作用。为进一步研究HSP70在人舌癌热疗联合免疫治疗初步提供了理论依据。     

人舌癌Tca8113细胞热休克蛋白多肽复合物(HSP70-PC)的提取和鉴定

采用ADP-Agarose亲和层析结合DEAE离子交换对Tca8113细胞的HSP70-PC进行分离纯化.结果显示在NaCl 250～350 mmol/L浓度处出现一洗脱峰,收集此峰各组分,经10% SDS-PAGE、在相对分子质量70 000处可见清晰单一蛋白条带,电泳后于第5峰发现相对分子质量为70 000的蛋白,此蛋白被洗脱的盐浓度为NaCl 250～350 mmol/L,此即为高纯度的HSP70-PC.HSP70获得率为1 g湿重的Tca8113细胞能纯化85 μg的HSP70-PC.采取低渗匀浆、超速离心、ConA-Sepharose亲和层析、ADP-Agarose亲和层析及DEAE离子交换的纯化方案,可获得高纯度的HSP70-PC.     

Mood and malignancy: head and neck cancer and depression

Head and neck cancer patients have been reported to show high rates of depression. However, it is important to differentiate between depressive symptoms and a depressive disorder. This review critically examines the relationship between head and neck cancer and depression. There appears to be little evidence for depression leading to an increased risk of developing cancer and although depressive symptoms in head and neck cancer patients are common, very few studies have investigated depressive disorders. The studies that investigated the incidence of a comorbid depressive disorder report a prevalence very close to that of the general population, implying that major depression is not a normal response to cancer. Finally, the evidence suggests that comorbidity of depression with cancer has a negative impact on morbidity and mortality. Both psychosocial and biological factors could account for this. Dysregulation of the stress hormone axis and increased inflammation are common in depressive disorders and have been suggested as underlying pathological mechanisms and are both markers of poor prognosis in cancer. This evidence suggests that a relatively small number of patients develop a depressive disorder following a diagnosis of cancer, but for those that do it may have a substantial impact on their prognosis.     

低氧和自噬与肿瘤的发生发展

自噬作为真核生物的一种应激调控机制,既可以促进肿瘤的发生发展,又可以抑制肿瘤的增殖。在肿瘤局部低氧的微环境下,低氧诱导因子-1α、哺乳动物雷帕霉素靶蛋白信号转导通路抑制、内质网应激均可促进自噬的发生。在肿瘤快速地发生发展过程中,肿瘤的糖代谢功能增强、活性氧族增多、窖蛋白1下调以及上皮间质转化的激活均诱导了自噬的发生并促进肿瘤的局部浸润、侵袭转移和耐药,因此,抑制自噬可能为肿瘤治疗提供一种新的策略。     

补体与牙周炎发生发展及其治疗

在牙周炎这一慢性炎症反应过程中,补体不仅可以调解机体防御反应,保护宿主,还可直接作用于免疫细胞或通过调控信号转导通路,协助病原菌进一步感染和破坏牙周组织,最终导致免疫病理性的损伤反应。在免疫炎症反应中,补体不仅可刺激白细胞分泌白细胞介素、肿瘤坏死因子和粒细胞-巨噬细胞集落刺激因子,调节辅助性T细胞和巨噬细胞,促进细胞免疫和T细胞依赖的抗体分泌,增强免疫效应的调节,提高机体免疫力;亦可引起的炎症反应可对组织造成损伤,引起牙周炎。以补体受体拮抗剂干扰补体受体-Toll样受体信号转导通路,有利于机体清除病原菌,达到防治牙周炎的目的。理解补体在牙周炎发生发展中的作用,可为牙周炎治疗探索新途径。     

Molecular biology and its applications in orthodontics and oral and maxillofacial surgery

Molecular biology is an exciting, rapidly expanding field, which has enabled enormously greater understanding of the biology of diseases and malfunctions in many fields. It chiefly concerns itself with understanding the interactions between the various systems of a cell, including the interrelationship of DNA, RNA and protein synthesis and how these interactions are regulated. Since the introduction of molecular biology into modern science, numerous other fields have been enabled to go ““molecular““. Advanced molecular biological techniques showed us new avenue towards finding answers to the questions asked for decades. The first part of this article described the history of molecular biology. It started as a joined discipline of other areas of biology, i.e. genetics and biochemistry in the 1930s and 1940s, and enjoyed its classical period and became institutionalized in the 1950s and 1960s. Major molecular techniques manipulating proteins, DNA and RNA were introduced and their mechanisms were concisely illustrated. The current knowledge of molecular biology and their applications in orthodontic and oral and maxillofacial surgery, i.e. osteoclast differentiation and function, regulation of tooth movement, mechanotransduction/cell-signalling, bone fracture healing, oral cancer as well as craniofacial/dental anomalies and distraction osteogenesis were discussed. Although the problems of introducing molecular technologies are still substantial, it is anticipated that the future of medicine/dentistry will be ““molecular““: molecular prevention, molecular diagnosis and molecular therapy.     

成釉细胞瘤、颌骨囊肿中E-cadherin、vimentin的表达及意义

目的通过免疫组化双染技术检测成釉细胞瘤(ameloblastomas,AM)、颌骨囊肿中E-cadherin、vimentin的表达情况,探索AM中是否存在上皮间充质转化(epithelial-mesenchymal transition,EMT)现象。方法选择37例不同分型的AM、5例颌骨囊肿为研究对象,用免疫组化双染技术检测E-cadherin、vimentin的表达情况,通过计数分析二者共同表达细胞的分布情况。单因素方差分析AM与颌骨囊肿、实性型与单囊型AM的EMT。结果 AM中存在EMT现象,EMT发生特点在实性型与单囊型AM之间、AM与颌骨囊肿之间均无统计学差异。结论 EMT与成釉细胞瘤的侵袭性生物学行为无相关性,EMT存在于AM中可能为肿瘤组织中间质细胞的来源之一。     

VEGF及受体在颌面部血管瘤和血管畸形中表达及意义

目的 检测细胞因子血管内皮生长因子(VEGF),血管内皮生长因子受体(VEGFR/KDR)及VEGF mRNA在颌面部血管瘤和血管畸形中的表达,探讨VEGF及其受体与血管瘤发病机制的关系。方法 采用二步EnVision免疫组织化学方法,分别检测27例血管瘤和15例血管畸形组织中VEGF和VEGF/KDR表达;同时采用原位杂交Gene Point法检测VEGF mRNA的表达。结果 VEGF和VEGFR/KDR在血管瘤中高表达,而在血管畸形组中低表达,两者有显著差异(P<0.01);VEGF和VEGF mRNA在血管瘤细胞及周围间质细胞明显表达,VEGFR/KDR主要表达于血管瘤中内皮细胞膜上。结论 VEGF可通过自分泌和旁分泌的形式影响血管瘤内皮细胞的增殖,可能与血管瘤发生、发展和退化有密切相关。     

Differences between and within human parotid saliva and nasal mucus cAMP and cGMP in normal subjects and in patients with taste and smell dysfunction

J Oral Pathol Med (2010) 40 : 504–509 Background: We previously described some of the moieties in human saliva and nasal mucus including cyclic nucleotides. However, comparison of levels of these latter moieties in saliva and nasal mucus has not been performed and meaning of differences found has not been discussed. Purpose: To compare the levels of cAMP and cGMP in saliva and nasal mucus and to describe the differences in their concentrations and function. Methods: cAMP and cGMP in saliva and nasal mucus were compared in normal subjects and patients with taste and smell dysfunction by use of a spectrophotometric colorimetric ELISA. Results: Both cAMP and cGMP were present in saliva and nasal mucus of normals and patients with levels of both moieties lower in patients than in normals. In normals, cAMP is 6½ times higher in saliva than in nasal mucus whereas cGMP in nasal mucus is 2½ times higher than in saliva. In patients, these differences persist but are less robust. In normals, within saliva, cAMP is 9½ times higher than cGMP whereas within nasal mucus cAMP is half the level of cGMP. In patients, within saliva, these differences persist but at variable differences. Conclusions: Both saliva and nasal mucus cAMP and cGMP play roles in taste and smell function, and differences in their concentrations may offer insight into these roles. In nasal mucus, cGMP may be more relevant than cAMP in activity of olfactory epithelial cell function. In saliva, cAMP may be more relevant as a growth factor in taste bud function than cGMP.     

Twins and twinning, dentists and dentistry

Comparisons of physical features within identical (monozygous) and non-identical (dizygous) twin pairs have provided valuable insights into the relative contributions of genetic and environmental influences to observed variability. The special nature of the twinning process itself also provides an opportunity to learn more about early human development, including how body symmetry is determined. The mechanisms of twinning, mortality and morbidity in twins, determination of body symmetry including the phenomenon of mirror-imaging, postnatal growth and development of twins, and zygosity determination are discussed. Twin studies with direct relevance to clinical dentistry are reviewed and illustrated by examples from an ongoing investigation of dentofacial morphology in South Australian twins.