肿瘤热疗的研究进展

肿瘤热疗是近年来研究的热点。肿瘤热疗后宿主机体的免疫功能发生变化,宿主全身抗肿瘤免疫反应被激活。本文从基础研究和临床试验两个方面对热疗后机体免疫功能的改变及其杀伤肿瘤的机理作一综述。     

肿瘤热疗的研究进展

肿瘤热疗是近年来研究的热点.肿瘤热疗后宿主机体的免疫功能发生变化,宿主全身抗肿瘤免疫反应被激活.本文从基础研究和临床试验两个方面对热疗后机体免疫功能的改变及其杀伤肿瘤的机理作一综述.     

肿瘤热疗中自动控温、恒温

肿瘤热疗技术在临床上得到了较为广泛的应用,但是对于人体深层部位的肿瘤,由于热能难于传至并集中于肿瘤部位,肿瘤热疗效果不理想.在当前肿瘤热疗中存在的另一个问题,即是准确、快速地测出热疗病灶部位的温度,仍然存在很大的困难,因而热剂量难于掌握,直接影响到肿瘤热疗的疗效.由于锰锌铁氧体磁性微粉吸收剂具有强烈吸收电磁波和存在居里温度的特性,采用在肿瘤热疗过程中,将锰锌铁氧体磁性微粉吸收剂输入血管中,可以达到对肿瘤热疗自动控温、恒温和提高疗效的目的.     

短波对兔VX2肿瘤热疗效果实验研究

目的 探讨短波热疗对荷VX2肿瘤的抑制作用.方法 选择一级新西兰兔49只,随机分成热化组(RH)13只、热疗组(R)13只、化疗组(H)12只和空白对照组(K)11只.移植VX2肿瘤10天后,对RH组施加热疗和化疗,R组施加热疗,H组施加化疗,K组不作任何处理,监测肿瘤的变化.结果 RH组、R组、H组和K组平均瘤重为9.1 g、29.81 g、16.62 g和29.93 g.RH组瘤重极显著小于对照组(P＜0.01),并显著小于H组(P＜0.05).肿瘤平均大小为:7.81 cm3、26.28 cm3、11.66 cm3和30.94 cm3,RH组肿瘤平均体积比H组小,但无显著性差异.结论 短波热疗结合化疗对兔VX2肿瘤的抑制作用明显高于单纯化疗.单纯热疗未见对肿瘤有明显的抑制作用.     

磁性纳米粒子在肿瘤热疗中的应用

本文介绍了肿瘤热疗及其存在的问题,并对磁热疗,磁性纳米粒子材料在热疗中的应用进行了综述。     

磁流体肿瘤热疗技术的研究进展

热疗在近年来已经成为肿瘤治疗最为重要的手段之一,但存在一定的局限性。磁流体热疗技术作为新兴发展起来的热疗手段,克服了常规热疗的缺陷,可以辅助治疗,甚至发展成独立治疗手段。本文综述了国内外近年来有关磁流体热疗基础研究及试验领域的最近进展,首先对磁流体特性、常见磁流体材料和交变磁场装置等方面进行了介绍,最后介绍了磁流体肿瘤热疗技术在体外试验、动物试验和临床研究方面的进展状况。虽然磁流体热疗逐步进入临床阶段,但仍存在不足,需要进一步的完善提高治疗效果。     

应用多晶铁纤维提高肿瘤热疗疗效的基础研究

肿瘤热疗已成为一种重要的治癌手段,但是对于人体深层部位的肿瘤,由于人体内各部脏器组织对电磁波的干扰及人体内各部分物理特性的非均匀性,肿瘤热疗的疗效并不显。本提出一种提高肿瘤热疗疗效的新方法,它能使肿瘤热疗既适用于浅层肿瘤的治疗又适用于深层肿瘤的治疗：通过静脉注射将多晶铁纤维注入血管,利用稳恒梯度磁场诱导多晶铁纤维定位于肿瘤病灶局部,然后在微波照射下,多晶铁纤维将有效地吸收微波能量,并将其转换成热能对肿瘤组织加热,杀灭肿瘤细胞。本对多晶铁纤维提高肿瘤热疗疗效的应用基础进行了研究,并得出重要结论;多晶铁纤维通过很强的畴壁运动损耗和宏观涡流损耗将入射的微波能量转换成热能从而对肿瘤加温;热疗过程中当微波频率为11GHz时多晶铁纤维吸收转换微波能量的效率最高;稳恒梯度磁场可用于诱导多晶铁纤维定位于肿瘤病灶局部等。随着研究的深入,多晶铁纤维将使肿瘤热疗发展成更为重要的肿瘤治疗手段。     

铁氧体微粉吸收剂提高肿瘤热疗疗效的机理探讨

铁氧体微粉吸收剂是一种高性能的磁性微波吸收剂。经静脉注射和磁场诱导定位于肿瘤后 ,铁氧体微粉可以充分吸收体外传入的微波能量 ,并将其转换成热能对肿瘤加热 ,因而可以提高热效率、改善热分布的均匀性及消除冷点。本文首先阐述了肿瘤热疗中存在的问题 ,然后介绍了铁氧体微粉在肿瘤热疗中的应用原理和方法 ,分析了铁氧体微粉的发热机理 ,并对铁氧体微粉在肿瘤化疗中的应用进行了探讨。     

应用多晶铁纤维提高肿瘤热疗疗效的基础研究

肿瘤热疗已成为一种重要的治癌手段 ,但是对于人体深层部位的肿瘤 ,由于人体内各部脏器组织对电磁波的干扰及人体内各部分物理特性的非均匀性 ,肿瘤热疗的疗效并不显著。本文提出一种提高肿瘤热疗疗效的新方法 ,它能使肿瘤热疗既适用于浅层肿瘤的治疗又适用于深层肿瘤的治疗 ;通过静脉注射将多晶铁纤维注入血管 ,利用稳恒梯度磁场诱导多晶铁纤维定位于肿瘤病灶局部 ,然后在微波照射下 ,多晶铁纤维将有效地吸收微波能量 ,并将其转换成热能对肿瘤组织加热 ,杀灭肿瘤细胞。本文对多晶铁纤维提高肿瘤热疗疗效的应用基础进行了研究 ,并得出重要结论 ;多晶铁纤维通过很强的畴壁运动损耗和宏观涡流损耗将入射的微波能量转换成热能从而对肿瘤加温 ;热疗过程中当微波频率为 1 1GHz时多晶铁纤维吸收转换微波能量的效率最高 ;稳恒梯度磁场可用于诱导多晶铁纤维定位于肿瘤病灶局部等。随着研究的深入 ,多晶铁纤维将使肿瘤热疗发展成更为重要的肿瘤治疗手段。     

新一代热疗技术:纳米材料介导的微纳尺度热疗

经典的热疗技术存在一些局限性,如适形性不佳、治疗范围有限以及复发率高等问题.纳米材料介导的微纳尺度热疗是新一代热疗技术,它利用纳米材料在病灶部位将外界物理场的能量转换为热能,以实现治疗效果,具有高度适形、远程可控、可结合多模态诊疗等优势,还可在肿瘤细胞内触发多种分子事件,激活抗肿瘤免疫反应,阻止肿瘤的复发和转移.微纳尺度热疗不仅能毁伤目标细胞,还可以调节细胞特定的生命活动,特别是通过热敏离子通道调控神经系统是近年来应用的焦点.本文回顾热疗技术的发展历程,综述纳米材料介导的微纳尺度热疗作为新一代热疗技术的特点及其优势,并具体阐述其在肿瘤治疗和神经调控两大领域的应用及前景.     

Photodynamic therapy of murine fibrosarcoma with topical and systemic administration of Hypericin

The in vivo antitumour activity of the natural photosensitizer hypericin was evaluated. C3H/DiSn mice inoculated with fibrosarcoma G5:1:13 cells were intraperitoneally or intratumourally injected with hypericin (5 mg/kg) and 2 hours later the mice were locally irradiated with laser light (488 nm, 150 mW/cm2, 180 J/cm2) when the tumour reached volume of 40-80 mm3 (approximately 17 days after inoculation). Tumours treated with hypericin alone as well as those irradiated with laser light alone have similar growth rates and none of these tumours regressed spontaneously. The mean tumour volume in hypericin-PDT treated groups was significantly lower in comparison to that found in the control group 3-5 weeks after the therapy. A higher proportion of animals with tumour volume less than 5-fold of the initial volume has been observed in both hypericin-PDT treated groups. Complete response to PDT has been observed for 44.4% of the animals with intraperitoneally administered hypericin and for 33.3% of the animals with intratumourally administered hypericin. Complete remission occurred in treated lesions with 3 mm or less in height. Hypericin-PDT significantly increased survival. However, no statistically significant difference in survival rate of animals has been found between the intratumoural and the intraperitoneal schedule of administration of hypericin.     

Photoinduced antitumour effect of hypericin can be enhanced by fractionated dosing

The in vivo antitumour activity of the natural photosensitizer hypericin was evaluated. C3H/DiSn mice were inoculated with fibrosarcoma G5:1:13 cells. When the tumour reached a volume of 40-80mm3 the mice were intraperitoneally injected with hypericin, either in a single dose (5mg/kg; 1 or 6h before laser irradiation) or two fractionated doses (2.5 mg/kg; 6 and 1 h before irradiation with laser light; 532 nm, 70mW/cm2, 168 J/cm2). All tumours in control groups treated with hypericin alone as well as those irradiated with laser light alone had similar growth rates and none of these tumours regressed spontaneously. Complete remission of tumour in photodynamic therapy (PDT)-treated groups was similar (14-17% single dose vs. 33% fractionated dose), but the fractionated schedule of hypericin dosing was found to be more efficient than the single dose, measured by survival assay (p < 0.05). Our experimental model showed that fractionated administration of hypericin can produce a better therapeutic response than single administration.     

Histomorphological changes in murine fibrosarcoma after hypericin-based photodynamic therapy

Histomorphological changes in murine fibrosarcoma after photodynamic therapy (PDT) based on the natural photosensitizer hypericin were evaluated. C3H/DiSn mice were inoculated with fibrosarcoma G5:1:13 cells. When the tumour reached a volume of 40-80 mm(3) the mice were intraperitoneally injected with hypericin, either in a single dose (5 mg/kg; 1 or 6 h before laser irradiation) or two fractionated doses (2.5 mg/kg; 6 and 1 h before irradiation with laser light; 532 nm, 70 mW/cm(2), 168 J/cm(2)). All groups of PDT-treated animals with single and fractionated hypericin dosing presented primary vascular reactions including vascular dilatation, congestion, thrombosis and oedema. Two hours after PDT there were necrotic changes with small, rather focal appearance. One day after therapy the necrotic areas were enhanced, often affecting a complete superficial layer of tumour tissue. Necrotic areas were accompanied with inflammation and haemorrhages.     

肠道细菌移位的研究进展

肠道是机体最大的生物库,定植着以细菌为主的种类繁多的微生物,共同构成肠道菌群。正常情况下肠道菌群与机体处于动态平衡,当各种原因引起肠道屏障功能损坏,致使细菌的数量、比例发生改变或空间上发生转移将引起肠道细菌移位,最终导致机体各种功能障碍。本文对肠道细菌移位的研究进行综述,为其防治提供相应的理论依据。     

小细胞肺癌药物治疗的研究进展

小细胞肺癌(small cell lung cancer,SCLC)约占肺癌患者总数的15%-20%,与吸烟关系密切,约60%-70%的患者就诊时已处于广泛期,预后很差,内科药物治疗仍然为其主要的治疗手段。由于其细胞生物学行为复杂,恶性程度高,易出现复发及耐药,通过多药联合、优化给药顺序、改变用药方法及调整药物剂量强度并没有获得预期的疗效,且毒副反应较多,其死亡率依然高居各种肿瘤之首,寻求有效的治疗方案变得迫切而棘手。近年来,随着SCLC内科治疗药物研究的不断深入,一些研究热点药物如bcl-2抑制剂、Hedgehog信号通路抑制剂、ipilimumab、贝伐单抗等已在Ⅱ期或Ⅲ期试验中显示出良好的抗肿瘤活性,为SCLC的药物治疗提供了新的方向。本文就目前针对SCLC的药物治疗进展情况作一综述。     

CD44v6: a target for antibody-based cancer therapy

The human CD44 gene encodes type 1 transmembrane glycoproteins involved in cell-cell and cell-matrix interactions. The structural heterogeneity of the gene products is caused primarily by alternative splicing of at least 10 out of 20 exons. Certain CD44 variant isoforms, in particular those containing CD44 variant domain 6 (CD44v6), have been implicated in tumourigenesis, tumour cell invasion and metastasis. Here we will give an overview of immunohistochemically determined CD44v6 expression in human malignancies (primary epithelial and nonepithelial tumours as well as metastases) and normal tissues, and review several examples of the clinical use of CD44v6-specific antibodies. In nonmalignant tissues, CD44v6 expression is essentially restricted to a subset of epithelia. Intense and homogeneous expression of CD44v6 was reported for the majority of squamous cell carcinomas and a proportion of adenocarcinomas of differing origin, but was rarely seen in nonepithelial tumours. This expression pattern has made CD44v6 an attractive target for antibody-guided therapy of various types of epithelium-derived cancers.Abbreviations CD44 type 1 transmembrane glycoprotein, cell surface receptor for hyaluronate - CD44s (CD44H) standard form of CD44 - CD44v6 splice variant exon 6 of CD44 - CTC common toxicity criteria - 2F10, VFF4, VFF7, VFF18 (BIWA 1), U36, V6B3, HB-256, Var 3.1 monoclonal antibodies targeting the CD44v6 antigen - SCC squamous cell carcinoma     

Photosensitization with protoporphyrin IX inhibits attachment of cancer cells to a substratum

Effects of photodynamic therapy (PDT) on adhesion of human adenocarcinoma cells of the line WiDr to a plastic substratum were investigated. Protoporphyrin IX induced by 5-aminolevulinic acid (ALA) was used as a photosensitizer. Light exposure inhibited attachment of suspended cells to a substratum. The adhesion was most strongly pronounced for light exposures around 200 mJ/cm(2) causing cell death. However, sub-lethal exposures (42 mJ/cm(2), 97% survival) inhibited cell adhesion as well. Sub-lethal ALA-PDT increased the intracellular space in dense colonies of WiDr cells. This was attributed to formation of lamellipodia between the cells and to increased numbers of focal contacts containing alpha(V)beta(3) integrin in some of the cells. The E-cadherin distribution was not changed by the treatment. Complex processes, including changes in cellular shape and reorganization of the cytoskeleton, are suggested to participate in the observed ALA-PDT effect on the cell adhesion.     

艾滋病合并丙型肝炎的抗病毒治疗临床观察

目的:观察艾滋病合并丙型肝炎的抗病毒治疗效果并回顾总结艾滋病合并丙肝的临床研究进展。方法:选择艾滋病合并丙型肝炎的患者33例,采用HAART疗法及干扰素联合利巴韦林治疗的方法,治疗4周后观察以上患者谷丙转氨酶(ALT)、谷草转氨酶(AST)、谷氨酸脱氢酶(GLDH)、总胆红素(TBIL)、白蛋白(ALB)和HCV-RNA检查结果,同时总结艾滋病合并丙肝的临床研究进展。结果:治疗4周后,以上患者ALT、AST、GLDH、TBIL、ALB和HCV-RNA阳性患者显著改善,治疗前后比较差异具有(高度)统计学意义(P<0.05,P<0.01)。结论:在对艾滋病合并丙型肝炎充分了解的同时,积极采取抗病毒治疗措施,可延缓疾病的发展。