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1.
目的 研究5-硝基吲唑-3-甲酰亚氨基二乙酸的细胞毒性,以及对HeLa细胞的放射增敏作用。方法 取指数生长期的HeLa细胞,接种于96孔板,加入不同浓度的药物作用后,用噻唑蓝比色法(MTT法)测定存活分数,并比较不同药物剂量加照射的实验组与单纯照射组的细胞存活分数。结果 5-硝基吲唑-3-甲酰亚氨基二乙酸对HeLa细胞的毒性较小。该药物对HeLa细胞有放射增敏作用,且乏氧处理的效果优于有氧处理:0、6、12、24、48、96μg/ml药物乏氧处理,存活率分别为0.91、0.87、0.84、0.81、0.76、0.60;48、96μg/ml药物有氧处理,存活率分别为0.85和0.73。结论 5-硝基吲唑-3-甲酰亚氨基二乙酸对HeLa细胞的毒性较小,且具有一定的乏氧放射增敏剂特征。  相似文献   

2.
探讨3-硝基三氮唑衍生物的放射增敏作用,并对其生物学效应作出评价。方法本文用克隆形成法研究了22个3-硝基-1,2,4-三氮唑衍生物的体外放射增敏活性和乏氧、富氧细胞毒性。结果两个化合物的活性胜过MISO,有三个化合物与MISO和SR-2508相当,其余的其活性均较低。3-硝基三唑衍生物也像2-硝基咪唑类那样,其放射增敏活性与电子亲和性(用半波还原电位E1/2表示)有关。亲和性越大,即E1/2值越偏正,增敏活性越强。环核N1位和5位上取代基的结构和性质影响着化合物的E1/2、分配系数p和细胞毒性。结论3-硝基三唑衍生物对乏氧和富氧(空气)细胞的毒性差别是很有限的,所以它们不是有效的乏氧调节细胞毒剂。但某些的放射增敏作用是值得深入研究的。  相似文献   

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Miso的神经毒作用主要是由于它的亲脂性.本文介绍了一种核苷类乏氧细胞增敏剂RP-170〔即:1-(2-羟基-1-羟甲基)乙氧基甲基-2-硝基咪唑〕,并与Miso和SR-2508在体内外的增敏、毒性等方面作了比较.体外实验选用Balb/c小鼠的EMT6/KU乳瘤细胞株.经培养的细胞用~(60)Co γ线(剂量率为1.0Gy/min)照射后以集落形成分析检测细胞活性.Balb/c Cr Slc小鼠EMT6/KU瘤和C3H/He N Slc小鼠SCCVⅡ瘤的增长研究用于体内实验.经接种二周后的两  相似文献   

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一般认为,实体瘤中的乏氧细胞是肿瘤放射治疗存在的主要问题。解决这一问题的最有希望的疗法之一是应用亲电子制剂,增强放射对乏氧细胞的致死效应。最有效的放射增敏剂是硝基咪唑类化合物Misonidazole(MISO)和第二代类似物SR2508与RO03-8799。这三个化合物现已进行广泛的临床试用,但由于神经毒副作用限制了疗效。本文作者试图克服神经毒副作用,研究了结构与硝基咪唑不同、特别是不含硝基的化合物,报告烟酰胺在小鼠体内作用特性的实验结果。资料指出了烟酰胺对小鼠的一般毒性、药代动力学和三种不同肿瘤与二种正常组织的放射增敏作用,并讨论了  相似文献   

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硝基杂环类化合物可用作乏氧细胞辐射增敏剂,它们的增敏效应与单电子还原电位(E_7~1)有关.本文介绍了具有较高电子亲和力的硝基呋喃类化合物的化学合成及其生物效应.5-硝基呋喃类化合物的亲电子能力大于2-硝基咪唑,因此它们的增敏效应比硝基咪唑类化合物  相似文献   

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目的探讨有氧与乏氧条件下^99Tc^m-巯基乙酰基-缬氨酸-甘氨酸-甘氨酸(MAVGG)-硝基咪唑硫嘌呤在肿瘤细胞的摄取及其在荷瘤小鼠体内的生物学分布和显像特点。方法用^99Tc^m-标记双功能螯合剂MAVGG偶联的硝基咪唑硫嘌呤。体外测定有氧与乏氧条件下标记物在S180肉瘤细胞内的滞留率。观察荷瘤小鼠体内生物学分布及其γ显像。结果乏氧条件下标记物与S180肉瘤细胞结合5h后,在S180肉瘤细胞内的滞留率为0.59,高于有氧条件下的0.36。生物学分布显示肿瘤摄取率高,注射后3h肿瘤与肌肉和血液的摄取率比值分别为4.24和1.55。γ显像示肿瘤显影清晰。结论^99Tc^m-MAVGG-硝基咪唑硫嘌呤有望作为新的肿瘤乏氧显像剂。  相似文献   

7.
KU-2285是N~1取代基为CH_2CF_2CONHCH_2CH_2OH的2-硝基咪唑衍生物,目前被认为是最有希望的乏氧细胞辐射增敏剂.研究通过与无-CF_2取代基的etanidazole比较,观察KU-2285体内辐射增敏效应和急性毒性反应,以估计其临床实用性.实验采用8~9周龄雌性C3H/He小鼠,接种SCCⅦ肿瘤或移植乳癌,照射采用10MVX射线,剂量率为5.6Gy/分.KU-2285和etanidazole在辛醇/水分配系数分别为0.250和0.040,还原电势〔E_(1/2)〕各为-0.96V和-1.05V.  相似文献   

8.
放射增敏剂研究进展   总被引:4,自引:0,他引:4  
放射增敏剂在肿瘤放疗中具有很大的实用价值,因而对它的研究日益受到重视,已先后合成并筛选出MISO等乏氧细胞放射增敏剂,对这些化合物的药效、毒性及临床都做了大量工作,同时还对具有放射增敏活性的生物还原剂及合并用药等作了研究。  相似文献   

9.
这一章包括的论文着重报道以下三个问题:<1>硝基咪唑(Miso)对乏氧细胞的优先毒性。<2>用Miso 预先处理乏氧细胞可使其在离体对化疗药物的敏感性增高(“预先孵育效应”)。<3>Miso 可使整体内的肿瘤细胞对化疗药物增敏。一、对乏氧细胞的毒性细胞存活曲线的形状:Miso〔1-(2-硝基咪唑-1-Yp)-3-甲氧基丙烷-2-01〕对乏氧细胞的优先细胞毒性首先被Hall 和Roijin-Towle 以及Moore 等人报道,Miso 对有氧细胞也有毒性,但需作用较长时间,或者相同作用时间但药物浓度增加15~50倍。学者们观察到Miso 有相同的细胞存活曲线:在5mM Miso 不同时间作用下乏氧细胞的存活曲  相似文献   

10.
目的 探究黄连素对乏氧环境中鼻咽癌细胞系CNE-2及裸鼠移植瘤的增敏效应及其分子机制。方法 四甲基偶氮唑盐比色法(MTT法)检测黄连素对CNE-2细胞的增殖抑制作用,克隆形成实验观察5 μmol/L黄连素对常氧和乏氧环境中CNE-2细胞放射敏感性的影响。黄连素乏氧下作用24 h后给予8 Gy X射线照射,流式细胞技术检测CNE-2细胞凋亡率。建立鼻咽癌CNE-2细胞裸鼠移植瘤模型,观察黄连素及单次8 Gy照射对移植瘤的抑制作用。Western blot检测乏氧条件下黄连素对HIF-1α及VEGF蛋白表达的抑制作用。 结果 黄连素显著抑制CNE-2细胞增殖,且存在时间、浓度依赖效应,24 h药物作用后半数抑制剂量IC50为(14.9±2.2)μmol/L。乏氧环境下,5 μmol/L黄连素处理后的克隆形成率较单纯乏氧组下降,其增敏比(SERD0)为1.27。在常氧环境中克隆形成率较乏氧组显著增加,常氧组和常氧加药组的SERD0分别为1.45和1.74。5和15 μmol/L黄连素能在乏氧环境中单独发挥促凋亡作用,与对照组比较差异有统计学意义(t=5.01、9.02,P<0.05),黄连素联合照射后,凋亡率较单纯照射组增加(t=5.31、9.91,P<0.05)。 体内实验显示,照射给药组肿瘤体积的增长显著延迟于对照组及单纯给药组,肿瘤倍增时间联合组较单纯照射组及对照组差异有统计学意义(t=2.96、14.52,P<0.05)。Western blot显示乏氧条件下HIF-1α、VEGF表达升高,黄连素作用24 h后表达显著下调。结论 黄连素对乏氧环境中的CNE-2细胞及裸鼠移植瘤有放射增敏作用,其与下调乏氧环境中HIF-1α及下游因子VEGF的表达有关。  相似文献   

11.
The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.  相似文献   

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Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).  相似文献   

15.
Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas (CCF) and their complications such as pseudoaneurysms. Methods: Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% (4/22). A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% (8/22). Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.  相似文献   

16.
Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.  相似文献   

17.
Introduction Interventional Radiology has evolved into a specialty having enormous input into the care of the traumatized patient.In all hospitals,regardless of size,the Interventional Radiologist must consider their relationships with the trauma service in order to  相似文献   

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KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief,intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.,≥90%of VO2 peak).  相似文献   

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The objective of the current paper is to report a new case of sexual murder involving human arson and summarize the literature on the phenomenon of sexual homicide. The present case study is unprecedented in Greece and a rarity in international literature due to the fact that the victim suffered genital mutilation and incineration while still alive. The evaluation consisted of 176 articles; 53 were reviewed by the authors. The results revealed sparse, but significant, research findings. The authors discuss the limitations regarding research, incidence of the phenomenon, crime-scene patterns, offender characteristics (killing methods, motive inferences, sociodemographic data, classifications, psychopathology, modus operandi), and victim selection. The incidence of the phenomenon is unclear (1–4%) due to non-standardized criteria. It is an expression of displaced anger or sexual sadism and/or a way to elude detection (ancillary benefit). Most offenders (in their first kill) and victims were in their late 20s to early 30s and belong to Caucasian populations. Personal weapons were commonly used against women, strangulation is the prevalent killing method against children, and firearms against men. Most of the sexual homicide perpetrators are non-psychotic at the time of the attack, but experience personality pathology, primitive defenses, pathological object relations, and withdrawal into fantasy in order to deal with social isolation.  相似文献   

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