5-氟尿嘧啶诱导人卵巢癌细胞凋亡的实验研究

 用不同剂量的5-氟尿嘧啶（5—Fu）处理人卵巢癌AO10／17细胞株，观察药物作用后细胞形态学，DNA片段化和细胞内钙离子浓度的变化。结果表明受药物影响的人卵巢癌细胞内ca⁺⁺升高，出现了细胞凋亡的形态改变。最后探讨了5—Fu抑制卵巢肿瘤细胞的作用机理。     

全脑照射对大鼠脑胶质瘤内顺铂浓度的影响

[目的]探讨大鼠脑胶质瘤受照射后瘤内顺铂(DDP)浓度的变化,为脑胶质瘤放疗提高依据。[方法]50只大鼠平均分为5组,采用立体定向方法在右侧尾状核接种C6细胞,肿瘤接种20d后MRI检查,确定肿瘤体积。60Coγ线行全脑单次外照射,剂量分别为0Gy、10Gy、15Gy、20Gy和30Gy。照射24h后经尾静脉注入DDP(8mg/kg),2h后取脑,分离肿瘤,以石墨炉原子吸收分光光度法测定DDP量浓度。[结果]0Gy、10Gy时,胶质瘤体较健侧半脑DDP质量浓度显著升高(P<0.05);胶质瘤体受照射10Gy后未见DDP质量浓度显著升高(P>0.05),受照射20Gy后出现DDP质量浓度显著升高(P<0.05),受照射30Gy后未见继续升高(P>0.05)。[结论]胶质瘤体内血脑屏障功能部分存在,受一定剂量照射后能够开放,超过一定剂量强度以后,胶质瘤血脑屏障通透性不再增加。照射剂量与DDP浓度的相关性有待进一步研究。     

6MV-X线单次高剂量照射肺腺癌细胞Anip973的超微结构观察北大核心CSCD

目的探讨6 MV-X线单次不同剂量照射后肺腺癌细胞系Anip973细胞损伤的超微结构变化。方法采用6 MV-X射线单次10、20 Gy照射肺腺癌细胞系Anip973,在24和48小时后透射电子显微镜下观察细胞损伤的超微结构变化。结果正常对照组细胞生长活跃,代谢旺盛。10 Gy照射后24小时细胞肿胀,可逆性损伤;48小时,细胞凋亡明显。20 Gy照射后24小时部分肿胀,部分细胞凋亡明显;48小时,胀亡为细胞主要改变,出现典型、广泛的溶解性坏死。结论在单次大剂量放射情况下,胀亡是细胞坏死的主要方式。照射后48小时出现典型形态改变—溶解性坏死。     

快中子及X射线诱导人直肠癌细胞凋亡及相关基因表达的研究

目的:研究及探讨快中子及X射线诱导人直肠癌细胞凋亡及其相关基因表达。方法：不同剂量X射线（0、2、4、6、8、10Gy）及具有同等放射生物学效应的相当于射线1／3剂量的不同剂量快中子（０、０.67、1.34、2.01、2.68、３.34Gy)照射细胞,于３７℃孵育６小时,２４小时,４８小时,７２小时后,进行Ｈoechest33342荧光染色,观察细胞凋亡形态并凋亡指数ＡＩ（凋亡细胞的百分数）;用电子显微镜观察凋亡细胞特有的形态学特征;此外,我们分别对不同剂量（0、2、4、6、8、10Gy)X射线及快中子（0、0.67、1.34、2.01、2.68、3.34Gy)照射后24小时的细胞用免疫组化方法进行基因表达p53及bcl-2)的检测。结果：不同剂量X射线和快中子照射的细胞凋亡指数,随着照射剂量和受照时间的延长而逐渐增加,在同一时间点,快中子诱导的细胞凋亡水平明显高于X射线;不同剂量快中子照射后的细胞,较阳性对照组,p53基因表达下调明显,bcl－2基因表达下调不明显;不同剂量快中子照射后的细胞,p53及bcl-2基因表达下调均不明显。结论：高能X射线和快中子诱导人直肠癌细胞的凋亡具有明确的时间－剂量相关性,随着受照后时间的延长和剂量的逐渐增大,凋亡指数渐趋升高,无明显变缓之势;快中子照射人直肠癌细胞,与X射线相比较,可引起较大的凋亡反应;此外,照射后p53及bcl-2基因表达下调,说明此两类基因都参与了细胞凋亡的基因调控。     

快中子及X射线诱导人直肠癌细胞凋亡及相关基因表达的研究

目的:研究及探讨快中子及X射线诱导人直肠癌细胞凋亡及其相关基因表达.方法:不同剂量X射线(0、2、4、6、8、10Gy)及具有同等放射生物学效应的相当于X射线1/3剂量的不同剂量快中子(0、0.67、1.34、2.01、2.68、3.34Gy)照射细胞,于37℃孵育6小时24小时48小时72小时后,进行Hoechest 33 342荧光染色,观察细胞凋亡形态并计数凋亡指数AI(凋亡细胞的百分数);用电子显微镜观察凋亡细胞特有的形态学特征;此外,我们分别对不同剂量(0、2、4、6、8、10Gy) X射线及快中子(0、0.67、1.34、2.01、2.68、3.34Gy)照射后24小时的细胞用免疫组化方法进行基因表达(p53及bcl-2)的检测.结果:不同剂量X射线和快中子照射的细胞凋亡指数随着照射剂量和受照时间的延长而逐渐增加,在同一时间点,快中子诱导的细胞凋亡水平明显高于X射线;不同剂量X射线照射后的细胞,较阳性对照组,p53基因表达下调明显,bcl-2基因表达下调不明显;不同剂量快中子照射后的细胞,p53及bcl-2基因表达下调均不明显.结论:高能X射线和快中子诱导人直肠癌细胞的凋亡具有明确的时间-剂量相关性,随着受照后时间的延长和剂量的逐渐增大,凋亡指数渐趋升高,无明显变缓之势;快中子照射人直肠癌细胞,与X射线相比较,可引起较大的凋亡反应;此外,照射后p53及bcl-2基因表达下调,说明此两类基因都参与了细胞凋亡的基因调控.     

高低剂量醛红叶酸合并氟脲嘧啶治疗晚期胃肠道癌

 本文观察了国产酸氢叶酸(CF)两种不同剂量(20mg/M²和200mg/M²)合并5-Fu静脉持续120小时滴注治疗晚期胃肠道癌52例的疗效.认为采用低剂量国产CF合并5-Fu联合化疗方案在临床上更合适,安全经济,有一定推广价值.     

全脑照射加拓普替康治疗肺癌脑转移剂量 递增试验

 目的通过全脑照射加拓普替康每周化疗综合治疗肺癌脑转移,观察其不良反应、耐受剂量及临床 可行性。方法18例肺癌脑转移患者成为研究对象,全程常规分割照射,全脑剂量40Gy/20次,病灶较大者 局部加量至50～60Gy。拓普替康的用量从低剂量逐渐上升至高剂量,起始剂量为1.0 mg/m²,1次/周,4次 ,递增剂量为0.25 mg/m²,每剂量组至少3例,如无剂量限制毒性（DLT）出现则进入下一剂量组,直至出 现DLT,DLT的次一剂量即为最大耐受量（MTD）。结果DLT为3级放射性骨髓抑制,发生在拓普替康2.0 mg/m²剂量水平;则其次一剂量1.75 mg/m²即为MTD。主要不良反应为放射性骨髓抑制。结论全脑照射加拓 普替康每周化疗治疗肺癌脑转移具有临床可行性;拓普替康的最大耐受剂量为1.75 mg/m²。     

丁基苯酞对放射性脑损伤模型大鼠皮质AQP4表达影响的观察

目的:观察丁基苯酞对单次全脑照射后大鼠大脑皮质水通道蛋白4 (AQP4)表达的影响.方法:将雄性SD大鼠60只随机分为假照射组、单纯照射组和丁基苯酞组,采用10 Gy单次全脑照射模型,制模后丁基苯酞组大鼠分别按剂量0.3、1.0和3.0 mg/kg丁基苯酞腹腔注射;依文思蓝(EB)法评价血脑屏障通透性改变;免疫组织化学法检测皮质AQP4表达的变化.结果:单纯照射组大鼠脑组织EB含量为(1.62±0.18) μg/g,与假照射组的(0.58士0.11)μg/g比较,差异有统计学意义,P=0.006;照射后1周单纯照射组大鼠脑组织皮质AQP4表达(1.67±0.63)较对照组(4.00土0.32)降低,P=0.004.与单纯照射组比较,不同剂量丁基苯酞组大鼠脑组织EB含量均降低(0.3mg/kg组,P=0.002;1.0 mg/kg组,P=0.004; 3.0mg/kg组,P=0.003);照射后1周不同剂量丁基苯酞组皮质AQP4表达有不同程度增加,呈现剂量依赖性(0.3mg/kg组,P=0.035;1.0 mg/kg组,P=0.042; 3.0 mg/kg组,P=0.006).结论:大鼠全脑照射后皮质AQP4表达呈时程性变化,丁基苯酞对AQP4有调节作用.     

四君子汤 对电离辐射损伤 的防治作用

目的：观察四君子汤对电离辐射所致免疫和造血系统损伤的防治作用,探讨其可能的机制。方法：采用CCK-8试剂盒检测不同终浓度（0、60、120、600、1 200 μg/mL）的四君子汤作用48 h对淋巴母细胞AHH-1的毒性作用,以及不同终浓度（0、0.04、0.2、1、25、120 μg/mL）的四君子汤预处理2 h对4 Gy ⁶⁰Co γ射线照射后AHH-1细胞存活率的影响。选择6~8周的BALB/c小鼠160只,用随机数字表法分为阴性对照组、照射对照组以及四君子汤0.75、2.25、6.75 g/kg剂量组。3.5 Gy γ射线全身单次照射造成小鼠电离辐射损伤模型。照射后第3和第7天,观察四君子汤对小鼠外周血淋巴细胞数及百分率、胸腺系数的影响。各组小鼠经5.5 Gy γ射线全身单次照射后,观察30 d并记录死亡小鼠数和死亡时间。结果：与照射对照组细胞（0 μg/mL）相比,四君子汤在0~120 μg/mL范围内对AHH-1细胞未见明显毒性（P > 0.05）,经120 μg/mL四君子汤处理的AHH-1细胞存活率显著提高（P < 0.05）。与照射对照组比较,照后3 d,四君子汤2.25 g/kg剂量组小鼠的外周血淋巴细胞数及百分率均显著升高（P均 < 0.05）;四君子汤6.75 g/kg剂量组的淋巴细胞百分率显著升高（P < 0.05）;照后第3和第7天,四君子汤6.75 g/kg剂量组的胸腺系数均显著升高（P均 < 0.05）。与照射对照组比较,四君子汤6.75 g/kg剂量组小鼠的30 d内平均存活时间及30 d生存率均显著增加（P均 < 0.05）。结论：四君子汤通过提高外周血淋巴细胞数、减少胸腺损伤,可缓解电离辐射所致损伤,促进小鼠免疫和造血功能恢复,并可促进γ射线照射小鼠的存活,可考虑作为电离辐射损伤防治药物作进一步的研究。     

肺癌脑转移患者全脑放疗后认知功能状况的研究北大核心CSCD

目的:探究肺癌脑转移患者全脑放疗后的认知功能状况。方法:回顾性分析2020年1月至2021年2月广州中医药大学金沙洲医院收治的146例肺癌脑转移患者资料。根据有无神经系统症状,分为A组(有,95例)和B组(无,51例)。采用多因素logistic回归分析危险因素,构建列线图预测模型并评价。结果:经全脑放疗后,临床有效者124例(84.9%),无效者有22例(15.1%)。全脑放疗后:A组患者的简明精神状态检查量表(MMSE)评分显著提高(P均<0.05),放疗后4个月时最显著,之后略有下降;B组患者的MMSE评分有所下降,放疗后4个月时最显著,之后有所恢复。多因素logistic回归分析显示,化疗≥3个周期、有同步加量、计划靶区照射剂量40 Gy、无海马区保护以及海马区照射剂量>30 Gy,均为认知功能下降的独立危险因素(P均<0.05)。列线图预测模型的评价结果显示,其区分度、准确度以及有效性均较高。危险分层系统将所有患者分为4个危险分组:极低(总分<90分)、低(90分≤总分<128分)、中(128分≤总分<152分)、高(总分≥152分)风险组。结论:对于肺癌脑转移患者,全脑放疗的临床疗效较好,但其对于患者认知功能有影响,放疗后4个月最显著。化疗≥3个周期、有同步加量、计划靶区照射剂量40 Gy、无海马区保护以及海马区照射剂量>30 Gy,均为认知功能下降的独立危险因素。     

The time course of radioprotection by WR 2721 in mouse skin

The radioprotective effect of 400 mg/kg of WR 2721 on mouse skin has been investigated over a series of times from 5 to 60 minutes after intravenous or intraperitoneal injection of the drug. The acute desquamation reaction on the hind leg of white mice was studied. Dose response curves were obtained for the average reaction over 15 to 25 days after single-dose irradiation. A high dose-rate electron beam (13–17 Gy/min) was used to minimize the irradiation time. Single doses of 20 to 60 grays were given. Dose modifying factors (DMFs) of 1.7-2.1 were obtained at 30 to 60 minutes, but only 1.1 to 1.3 at 5 minutes and intermediate values at 10 and 15 minutes. DMFs rose slightly faster and to slightly higher values after i.v. than after i.p. injection of WR 2721. We conclude that 30 minutes is the shortest interval which should be used between injection of WR 2721 and irradiation with this normal tissue.     

照射对血—脑屏障促进化疗药物透过性的影响

用氢甲碟呤（ＭＴＸ）静脉注射观察脑部照射前、中、后，ＭＴＸ由血管向脑脊液渗透的动态变化作为定量研究照射剂量对血－脑脊液屏障的影响。通过１７例脑瘤照射观察，血脑屏障开放者１１例，不开放者６例。脑瘤体积大的病人，其血－脑脊液屏障受损明显，而瘤体小的病例，其血－脑脊液屏障基本完好，照射２０Ｇｙ后，屏障窗孔逐渐开放，与照射前相比，ＭＴＸ透过性增加１～３倍，所以照射２０Ｇｙ后，开始给化疗药是最佳时期。     

Fundamental studies on locally injected methotrexate bound to activated carbon particles (MTX-CH)

We developed a new dosage formulation of methotrexate bound to activated carbon particles (MTX-CH). In this study, subcutaneous injection of MTX-CH was examined for its long-acting effect at the injection sites, anti-tumor effect and acute toxicity in mice. MTX-CH- or MTX aqueous solution (MTX-SOL)- was injected locally into tumors growing on the back of BALB/c mice at a dosage of 30 mg/kg as methotrexate (MTX). (1) The MTX concentration at the injection sites remained higher in mice with MTX-CH than that with MTX-SOL. (2) A marked effect on the control of tumor growth by MTX-CH was noted after repeated injections throughout the observation period. These results suggest that MTX-CH is superior to MTX-SOL due to longer-acting effects at the administration site and have a better control of tumor growth than MTX aqueous solution (MTX-SOL).     

急性淋巴细胞白血病小鼠甲氨蝶呤化疗后血及脑组织药物浓度的对比研究

 目的　探索急性淋巴细胞白血病小鼠不同剂量甲氨蝶呤（MTX）化疗后血和脑组织药物浓度的关系。方法　4周龄清洁级普通昆明小鼠80只：建立急性淋巴细胞白血病小鼠模型,随机抽取20只小鼠经股骨取骨髓行骨髓细胞学检查作模型验证;依据MTX化疗剂量与标本采取时间点的不同将余60只急性淋巴细胞白血病小鼠分为六组,每组10只,分别为A、B、C、D、E、F组;各组均取0.5 ml血液及0.4 g脑组织,血液离心,脑组织匀浆后离心,取上清用荧光偏振免疫方法检测药物浓度。结果　A、B、C、D、E、F六组平均MTX血药浓度分别为（39.08±5.18）μmol／L、（15.86±1.02）μmol／L、（8.67±5.43）μmol／L、（68.29±5.19）μmol／L、（29.55±6.22）μmol／L、（13.98±1.12）μmol／L,组间比较差异有统计学意义（P＜0.05）;各组脑组织平均MTX浓度依次为：（1.05±0.26）μmol／L、（0.61±0.25）μmol／L、（0.48±0.25）μmol／L、（2.07±0.35）μmol／L、（1.27±0.21）μmol／L、（0.59±0.69）μmol／L,组间比较差异有统计学意义（P＜0.05）;六组血与脑组织药物浓度相关系数依次为：0.82、0.75、0.19、0.81、0.55、0.43。结论　急性淋巴细胞白血病小鼠经大剂量MTX（HD-MTX）方案化疗后,于0.5 h出现血及脑组织药物浓度峰值,5 g／m2较3 g／m2能更好地透过血脑屏障使脑组织药物浓度达到有效治疗浓度。     

Effects of single-dose and fractionated cranial irradiation on rat brain accumulation of methotrexate

The effects of single-dose and fractionated whole-brain irradiation on brain methotrexate (MTX) has been studied in a rat model. The amount of MTX present in the brain 24 hr after a single i.p. dose (100 mg/kg) was the same wether animals were sham irradiated or given a single dose of 2000 rads 6 or 48 hr prior to the drug (6.9, 8.3, and 6.8 pmol MTX/g, wet weight, respectively). Animals sham irradiated or given 2000 rads in 10 fractions over 11 days and treated with an average dose of 1.2 mg MTX/kg i.p. twice a week for 24 weeks did not differ significantly in their brain MTX concentration (7.9 and 8.3 pmol MTX/g, wet weight, respectively). Chronically MTX-treated animals became folate deficient whether they were irradiated or not (450 and 670 pmol folate/g, wet weight, brain in MTX-treated and control animals). Thus, MTX accumulates in the brain with acute or chronic administration, and this accumulation is not altered by this amount of brain irradiation.     

Improved efficacy of chemotherapy for glioblastoma by radiation-induced opening of blood-brain barrier: clinical results

PURPOSE: To improve the efficacy of chemotherapy for glioblastoma through the radiation-induced opening of the blood-brain barrier (BBB). METHODS AND MATERIALS: In two previous articles, we have described the results of brain scanning using technetium 99m-labeled somatostatin and the measurement of methotrexate (MTX) concentrations in blood and cerebrospinal fluid (CSF) after i.v. injection. We discovered that the BBB and blood-cerebrospinal fluid barrier opened to a certain extent after 20- to 40-Gy irradiation, thus increasing the degree to which MTX permeated the brain tissue. On the basis of these findings, we retrospectively analyzed the outcome in 56 patients with glioblastoma given either chemotherapy (CCNU) after 20- to 40-Gy irradiation (28 patients) or radiation therapy alone (28 patients). RESULTS: The 1-, 3-, and 5-year survival rates were 57.14%, 22.50%, and 15.00% in the combined-therapy group and 17.86%, 7.14%, and 3.57% in the radiotherapy alone group, respectively. The respective median survival times were 29.11 +/- 6.99 and 9.86 +/- 3.45 months (p < 0.001), which represented a statistically significant difference. CONCLUSION: Our study further confirms that opening of the BBB induced by irradiation with 20-40 Gy may optimize the effects of intracranial chemotherapy.     

Influence of C6 and CNS1 Brain Tumors on Methotrexate Pharmacokinetics in Plasma and Brain Tissue

PURPOSE: Comparison of the influence of two different brain tumors (C6 and CNS1 glioma) on methotrexate (MTX) disposition in plasma, brain, and tumor tissue extracellular fluid (ECF). METHODS: Serial collection of plasma samples and brain ECF dialysates after i.v. bolus administration of MTX (50 mg kg(-1)) for 4 h. Quantitation of MTX concentrations by HPLC-UV. RESULTS: Histological studies revealed a 3-fold higher number of blood vessels in CNS1 than in C6 tumor tissue. In vivo recoveries (reverse dialysis) were significantly different in tumor tissue (C6: 8.0 +/- 3.8%; CNS1: 4.9 +/- 2.5%), and in the contralateral hemisphere (C6: 6.0 +/- 4.0%; CNS1: 3.9 +/- 2.5%) between the two tumors. Area under the concentration-time curve (AUC) in plasma was 30% higher in CNS1 than in C6 due to a lower systemic clearance. Maximum MTX levels in brain tumor ECF were significantly higher in CNS1 than in C6, and decreased faster in CNS1 than in C6 tumor-bearing rats. Penetration in tumor ECF (AUC(ECF)/AUC(Plasma) ratio) was similar in CNS1 and C6. MTX concentrations in contralateral hemisphere were significantly lower than in tumor tissue and dependent on tumor model. CONCLUSION: C6 and CNS1 brain tumors have a distinct yet highly variable impact on MTX penetration in brain and brain tumor ECF.     

Distribution and degradation of [3H]methotrexate after intravenous and cerebral intraventricular injection in primates.

Four hr after either a single injection or continuous infusion of methotrexate (MTX) plus purified [3',5',9(n)-3H]MTX in cynomolgus or rhesus monkeys, 80 to 98% of the 3H radioactivity present in the plasma was found not to represent intact MTX. The percentage of 3H-containing MTX products in the urine after 4 hr was considerably less, although more variable. This variability seemed to be related to variability in the amount of the total dose excreted. Non-MTX products were also found in selected tissues and the percentage of intact MTX found 4 hr after i.v. injection varied from 2 to 26%. The percentage of intact MTX was routinely measured by comparing the values obtained using the dihydrofolate reductase assay with values based on the specific activity of [3',5',9(n)-3H]MTX. Results obtained by diethylaminoethyl column chromatography on a few samples, however, showed good agreement with results from the reductase assay. [3',5',9(n)-3H]MTX products appeared in peaks eluting from the diethylaminoethyl column both earlier and later than the MTX peak, with the earlier peaks being present in only small amounts in the urine. After continuous i.v. infusion, only 2% or less of the radioactivity found in the cerebrospinal fluid after 4 hr represented intact MTX, with the remaining radioactivity eluting much earlier than MTX. In contrast, after direct injection into the left lateral ventricel, all the 3H radioactivity in both cerebrospinal fluid and brain tissue represented intact MTX for up to 4 hr after injection. The appearance of MTX products in the plasma and selected tissues of these primates a short time after i.v. injection is compared to other work in experimental animals and man and suggests a greater metabolism of MTX than was previously suspected.     

Toxicity of trimetrexate on hemopoietic progenitor cells in normal mice

Single increasing doses of methotrexate (MTX) and trimetrexate (TMQ) were administered to normal mice. Survival of hemopoietic progenitor cells assayed as CFU-S and GM-CFC was determined 24 hr after drug injection. The survival of each population in TMQ-treated animals was not statistically different from that observed in mice treated with MTX. No difference was observed in time-survival curves of hemopoietic progenitor cells comparing TMQ to MTX. TMQ toxicity at the hematological level thus seems comparable to that of MTX.     

Interactions of radiation and 5-fluorouracil,cyclophosphamide or methotrexate in intestinal crypt cells

The interactions of radiation and 5-fluorouracil (5-FU), cyclopbosphamide (CTX), or methotrexate (MTX) in mouse jejunal crypt cells were studied using the microcolony survival may. 5-FU given from 48 hr before to 24 hr after irradiation resulted in an almost constant, increased cell kill except at injection 6 hr after irradiation, which resulted in a more pronounced effect. CTX enhanced the radiation effect only when given simultaneously with or up to 3 br after irradiation. The effect of MTX, extremely dependent on the sequence and interval between drug administration and irradiation, was most prominent when administered 1 hr before irradiation. At this drug-radiation interval, the Do surprisingly increased by a factor of 2.4, whereas MTX 15 min before irradiation displaced the survival curve to the left without changing the D₀. The influence of MTX on the radiation response disappeared when the drug was given either % hr before or 3 hr after irradiation.