核桃低聚肽对６０Ｃｏγ射线照射小鼠氧化损伤 保护作用的实验研究

摘要：目的　探讨核桃低聚肽（ＷＯＰｓ）对６０Ｃｏγ射线辐照小鼠氧化损伤的保护作用。方法　将９６ 只ＳＰＦ 级雌性ＢＡＬＢ／ｃ小鼠随机分为６ 组：空白对照组、模型对照组、乳清蛋白组（０．４４ｇ／ｋｇ）、ＷＯＰｓ组低、 中、高组（０．２２ｇ／ｋｇ、０．４４ｇ／ｋｇ、０．８８ｇ／ｋｇ）,连续饮水途径给予不同溶液第１４ 天,除空白对照组外, 所有小鼠全身照射３．５ Ｇｙ剂量６０Ｃｏγ 射线,分别在辐照后第３ 天和第１４ 天检测小鼠血清及肝脏ＳＯＤ、 ＧＳＨ Ｐｘ活性及ＭＤＡ 含量。结果　辐照降低了小鼠肝脏及血清ＳＯＤ、ＧＳＨ Ｐｘ含量,增高了ＭＤＡ 含量。 辐照后第３ 天,ＷＯＰｓ中组小鼠肝脏及血清ＳＯＤ 活性均高于模型对照组和乳清蛋白组（犘＜０．０５）;辐照后 第１４ 天,ＷＯＰｓ低组小鼠肝脏及血清ＳＯＤ 活性均高于模型对照组和乳清蛋白组（犘＜０．０５）。辐照后第 ３ 天,ＷＯＰｓ低组小鼠肝脏及血清ＧＨＳ Ｐｘ 活性均高于模型对照组和乳清蛋白组（犘＜０．０５）; 辐照后第 １４ 天,ＷＯＰｓ低组小鼠肝脏及血清ＧＳＨ Ｐｘ活性均高于模型对照组和乳清蛋白组（犘＜０．０５）。辐照后第 ３ 天,ＷＯＰｓ低、中组小鼠肝脏和血清ＭＤＡ 含量均低于模型对照组和乳清蛋白组（犘＜０．０５）; 辐照后 第１４ 天,ＷＯＰｓ低、中、高组小鼠肝脏及血清ＭＤＡ 含量均低于模型对照组和乳清蛋白组（犘＜０．０５）。结 论　ＷＯＰｓ对辐照所致氧化损伤具有一定的保护作用。 关键词：核桃低聚肽;辐照;氧化损伤;超氧化物歧化酶;谷胱甘肽过氧化物歧化酶;丙二醛 中图分类号：Ｒ１５１　　文献标识码：Ａ　　文章编号：１００９ ６６３９ （２０１９）０３ ０２１２ ０５     

DDC与平阳霉素联合应用治疗小鼠P388肿瘤的实验研究

应用小鼠Ｐ３８８实体瘤模型，进行了二乙基二硫代氨基甲酸钠（ＤＤＣ）增强平阳霉素（ＢＬＭＡ５）抗癌活性的实验。结果表明，在ＢＬＭＡ５１２ｍｇ／ｋｇ、１５ｍｇ／ｋｇ及２４ｍ／ｋｇ３个剂量组分别辅加５００ｍｇ／ｋｇＤＤＣ后，抑癌率明显高于单独用ＢＬＭＡ５的试验组。给小鼠ｉｐ５００ｍｇ／ｋｇ、７５０ｍｇ／ｋｇＤＤＣ，在３０ｍｉｎ、１ｈ、４ｈ时，受试小鼠的ＳＯＤ活性丧失至０，到２４ｈ时，ＳＯＤ活性才恢复到正常的４０％。结果提示，减少Ｃｕ２＋的水平及增加Ｏ＿２￣－的浓度可以修饰ＢＬＭＡ５的细胞毒性。     

海藻硫酸多糖抗氧化与抗肿瘤作用的实验研究

目的：观察海藻硫酸多糖（ＳＰ）对正常及荷瘤小鼠肝匀浆及红细胞中ＳＯＤ，ＧＳＨ－Ｐｘ活性及脂质过氧化产物ＭＤＡ含量的影响，探讨其抗氧化与抗肿瘤之间的关系。结果：移植肿瘤Ｓ１８０使肝组织中ＳＯＤ，ＧＳＨ－Ｐｘ活性分别由１１３．７３±８．１７降至７１．４１±１０．９８ｍｇ／Ｌ（Ｐ＜０．０５），３２．３４±０．０５降至２９．９６±０．１６Ｕ（Ｐ＜０．０１），ＭＤＡ含量由０．２３４±０．００１增至０．２８０±０．０１２（Ｐ＜０．０５），腹腔注射或口服ＳＰ则使ＳＯＤ，ＧＳＨ－Ｐｘ活性增至１１８．７７±１８．９２ｍｇ／Ｌ（Ｐ＜０．０５），３６．５８±１．０６Ｕ（Ｐ＜０．０１），ＭＤＡ含量降至０．１０４±０．０３９（Ｐ＜０．０１）。且腹腔注射ＳＰ１００ｍｇｋｇ－１ｄ－１×１０ｄ可使肿瘤抑制率达３９．１３％，口服ＳＰ２００ｍｇｋｇ－１ｄ－１×１０ｄ也能使肿瘤抑制率达２８．０４％。结论：ＳＰ抑瘤作用的机理可能与抗氧化有关。     

苯对作业工人血清中SOD活力及LPO含量影响的研究

９２名油漆工为观察组，５７名行政人员、教师和学生为对照组，观察其白细胞计数（ＷＢＣ）、血清过氧化脂质（ＬＰＯ）含量及超氧化物歧化酶（ＳＯＤ）的活力。结果；观察组ＷＢＣ异常［低于４０００／ｍｍ３（４×１０９／Ｌ）］检出率高于对照组（Ｐ＜０．０１）；ＳＯＤ活力高于对照组（Ｐ＜０．０５），且与ＷＢＣ呈负相关。观察组中ＷＢＣ低于４０００／ｍｍ３（４×１０９／Ｌ）的人群，其血清ＳＯＤ活力高于ＷＢＣ４０００／ｍｍ３以上的人群。在ＷＢＣ高于４０００／ｍｍ３（４×１０９／Ｌ）的人群中，血清ＳＯＤ活力观察组也高于对照组。说明苯对作业工人血清中ＳＯＤ水平有影响，且比较敏感，其意义有待进一步研究。ＬＰＯ两组无差别。Ｐ＜０．０１２．３ＬＰＯ及ＳＯＤ测定结果观察组ＬＰＯ值低于对照组，但统计学处理差异无显著意义。ＳＯＤ活性观察组高于对照组，差异具有显著意义（Ｐ＜０．０５）。观察组按工龄及吸烟与否分组，各组间ＳＯＤ活性无显著性差异（表３）。表３观察组与对照组血清ＬＰＯ、ＳＯＤ测定结果比较＊ｐ＜０．０５２．４ＷＢＣ、ＬＰＯ、ＳＯＤ之间相关性分析ＳＯＤ与ＬＰＯ之间、ＷＢＣ与ＬＰＯ之间相关关系不明显（ｐ＞０．０５），而ＷＢＣ与ＳＯＤ之间呈负相     

外源性超氧化物歧化酶对氯化汞免疫毒性的影响

采用免疫毒理学方法观察外源性ＳＯＤ对汞的免疫毒性的影响。结果氯化汞染毒的ＩＣＲ小鼠血中碳廓清率、ＳＲＢＣ致敏小鼠迟发型过敏反应（ＤＴＨ），ＤＮＣＢ所致的迟发型皮肤过敏反应（ＤＣＨ），血清溶血素（Ｈｃ５０）和免疫脏器系数均明显低于对照组，预先给予ＳＯＤ后再给同剂量氯化汞的小鼠除Ｈｃ５０外上述各指标均有不同程度提高。免疫器官脂质过氧化作用，汞组脂质过氧化物（ＬＰＯ）含量明显高于对照组，ＳＯＤ活性比对照组明显降低（Ｐ＜０．０１），而ＳＯＤ－汞组与汞组比较，ＬＰＯ含量明显降低，ＳＯＤ活性明显升高（Ｐ＜０．０５）。提示外源性ＳＯＤ能拮抗氯化汞所致的免疫毒性和脂质过氧化作用。     

白魔芋精粉对荷瘤小鼠的抑瘤和免疫增强作用

方法：用２５、５０、１００ｍｇ／ｋｇ白魔芋精粉（ＡＡＰ）对Ｓ１８０、ＥＡＣ、Ｈｅｐｓ和Ｕ１４四瘤株进行了动物移植性肿瘤的抑瘤试验。结果：ＡＡＰ对Ｓ１８０、ＥＡＣ、Ｈｅｐｓ和Ｕ１４的抑瘤率分别为５９．７４％、５４．０２％、５２．７９％和４０．８６％。ＡＡＰ能显著增强荷瘤小鼠单核巨噬细胞的吞噬功能，与对照组相比，差异极显著（Ｐ＜０．０１），Ｔ淋巴细胞转化能力也显著高于对照组（Ｐ＜０．０１），肿瘤相伴免疫试验显示ＡＡＰ治疗组的长瘤率与瘤重均明显小于对照组     

β-胡萝卜素和核黄素对大鼠脂质过氧化的影响

目的：进一步探讨亚硝胺通过脂质过氧化而致癌的可能途径,以及研究β－胡萝卜素（β－Ｃ）和核黄素（ＶＢ２）通过抑制脂质过氧化反应而影响亚硝胺致癌的可能途径。方法：将５０只二级ＳＤ雄性大鼠随机分成５组。实验组在每日灌胃二甲基亚硝胺（ＮＤＭＮ）１．７５ｍｇ／ｋｇ的基础上,每日分别给予β－Ｃ２５ｍｇ／ｋｇ和／或ＶＢ２１８ｍｇ／ｋｇ补充,实验期为２８天。实验结束时,收集血液,摘取肝脏和肾脏,测红细胞和肝肾匀浆ＳＯＤ活性,全血ＧＳＨ－Ｐｘ活性,血清和肝肾匀浆ＭＤＡ含量,血清ＲＯＯＨ以及全血Ｈｂ含量。结果：１．ＮＤＭＮ可使ＳＯＤ和ＧＳＨ－Ｐｘ活性下降（Ｐ＜０．０５）,ＭＤＡ和ＲＯＯＨ产生增多（Ｐ＜０．０５）。２．添加β－Ｃ后,ＳＯＤ和ＧＳＨ－Ｐｘ活性有明显提高（Ｐ＜０．０５）,ＭＤＡ和ＲＯＯＨ的含量明显降低（Ｐ＜０．０５）。３．添加ＶＢ２后,肝ＳＯＤ和全血ＧＳＨ－Ｐｘ活性均有明显提高（Ｐ＜０．０５）,但ＭＤＡ和ＲＯＯＨ的含量没有差异（Ｐ＞０．０５）。４．同时补充β－Ｃ和ＶＢ２后,各项指标的变化与单纯β－Ｃ组基本一致。结论：脂质过氧化也是亚硝胺致癌的途径之一;一定剂量的β－Ｃ可对抗ＮＤＭＮ引发的脂质过氧化;核黄素对提高抗氧化?     

IQ CT阴极输出模块故障维修实例

故障现象机架工作正常,控制台高压ＲＥＡＤＹ灯不能点亮,即高压不能上电。打开机架,在高压控制及输出部分分别发现模拟控制板（ＡＮＡＬＯＧＹＣＯＮＴＲＯＬＬＢＯＡＲＤ）的ＤＳ７灯点亮,提示板上 １５Ｖ控制电源（ １５ＶＳＷＩＴＣＨ）故障;在阴极输出模块（ＣＡＴＨＯＤＯＵＴＰＵＴＭＯＤＵＬＥ）上ＤＳ９灯亮,提示模块 １５Ｖ控制电源（ １５ＶＳＷＩＴＣＨ）故障;在逆变诊断控制板（ＩＮＶＥＲＴＥＲＤＩＡＧＮＯＳＴＩＣＢＯＡＲＤ）上的ＤＳ１５灯点亮,提示板上 １５Ｖ控制电源（ １５ＶＳＷＩＴＣＨ）故障;在系统控制板（ＳＹＳ…     

职业性肺癌HSPs与多种瘤抑制基因,k—ras表达的相关性

目的 观察ＨＳＰ２７，ＨＳＰ７０与多种瘤抑制基因（ＭＴＳ１），ｋ－ｒａｓ基因及其蛋白产物在职业性肺癌（ｏｃｃｕｐａｔｉｏｎａｌｌｕｎｇｃａｎｃｅｒ，ＯＬＣ）中的联合表达的情况，方法 采用免疫组化和原位分子杂交技术。结果 ＯＬＣ中的ＨＳＰｓ较正常肺组织高，ＯＬＣ中的ＨＳＰｓ与ｋ－ｒａｓ都有基因扩增和蛋白产物的过表达；ＭＴＳ１的表达与ＨＳＰｓ，ｋ－ｒａｓ的表达呈负相关，结论ＭＴＳ１表达的变化可能是ＯＬ     

外源性超氧化物歧化酶对醋酸铅免疫毒性的影响

目的探讨外源性超氧化物歧化酶（ＳＯＤ）对醋酸铅免疫毒性的拮抗作用。方法采用免疫毒理学方法观察外源性ＳＯＤ对醋酸铅免疫毒性的影响。结果醋酸铅染毒的昆明种小鼠血中碳粒廓清率、ＳＲＢＣ致敏小鼠迟发型过敏反应（ＤＴＨ）、ＤＮＣＢ所致的迟发型皮肤过敏反应（ＤＣＨ）、血清溶血素（Ｈｃ５０）和免疫脏器系数均明显低于对照组,预先给于ＳＯＤ后再给同剂量醋酸铅的小鼠除Ｈｃ５０外上述各指标均有不同程度提高,免疫器官脂质过氧化物（ＬＰＯ）含量,醋酸铅组明显高于对照组,而ＳＯＤ－醋酸铅组ＬＰＯ含量比醋酸铅组明显降低（Ｐ＜０．０１）。结论外源性ＳＯＤ能拮抗醋酸铅所致的免疫毒性和脂质过氧化作用。     

维生素C对S180移植腹水瘤荷瘤小鼠的影响

目的：研究不同剂量维生素C对S180移植腹水瘤荷瘤小鼠一般状况及免疫水平的影响。方法：建立小鼠S180移植腹水瘤模型，维生素C干预7天后处死，测定小鼠血红蛋白含量，白细胞数目及体液免疫指标（血清溶血素）。细胞免疫指标（小鼠足跖肿胀实验）和脏／体重比值，结果：维生素C对荷瘤小鼠的血象改变有一定保护作用，对免疫脏器损伤有一定保护，但总体未见显性差异（P＞0．05），维生素C对荷瘤小鼠的免疫功能具有显保护作用（P＜0．01，P＜0．05），且呈剂量依赖趋，结论：维生素C可提高荷瘤小鼠的免疫功能，并具有减轻荷瘤小鼠脏器受损程度及改善荷瘤小鼠血红蛋白含量的作用。     

Low-dose radiation induces adaptive response in normal cells, but not in tumor cells: in vitro and in vivo studies

Biological effects of low-dose radiation (LDR) are distinguishable from those of high-dose radiation. Hormetic and adaptive responses are such two examples. However, whether adaptive response could be induced in tumor cells by LDR, especially under in vivo condition, remains elusive, and was systemically investigated in the present study. Four tumor cell lines: two human leukemia cell lines (erythroleukemia cell line K562, and acute promyelocytic leukemia cell line HL60), and two human solid tumor cell lines (lung carcinoma cell line NCI-H446 and glioma cell line U251), along with one normal cell line (human fibroblast cells, MRC-5), were irradiated with LDR at 75 mGy of X-rays as D1 and then 4 Gy of X-rays as D2 (i.e.: D1 + D2) or only 4 Gy of X-rays (D2 alone). Three tumor-bearing animal models were also used to further define whether LDR induces adaptive response in tumor cells in vivo. Adaptive response was observed only in normal cell line, but not in four tumor cell lines, in response to LDR, showing a resistance to subsequent D2-induced cell growth inhibition. Three tumor-bearing mouse models with U251, NCI-H446 or S180 tumor cells were used to confirm that pre-exposure of tumor-bearing mice to D1 did not induce the resistance of tumor cells in vivo to D2-induced tumor growth inhibition. Furthermore, a higher apoptotic effect, along with higher expression of apoptosis-related genes P53 and Bax and lower expression of anti-apoptosis gene Bcl-2, was found in tumor cells of the tumor-bearing mice exposed to D1 + D2 than those in the tumor cells of the tumor-bearing mice exposed to D2 alone. These results suggest that LDR does not induce adaptive response in the tumor cells under both in vitro and in vivo conditions, which is a very important, clinic-relevant phenomenon.     

全反式维甲酸联合三氧化二砷抗膀胱癌作用及其毒副作用的实验研究

目的观察全反式维甲酸（ATRA）联合三氧化二砷（As2O3）对膀胱癌细胞株BIU-87裸鼠移植瘤生长的抑制作用,及其毒副作用。方法建立人膀胱癌裸鼠皮下移植瘤模型40只,随机等分为4组：对照组,ATRA组,As2O3组,ATRA和As2O3联合用药组;裸鼠瘤体内连续注射用药14d。停药后48h检测血常规和肝、肾功能;处死裸鼠,测量移植瘤体积、重量,计算抑瘤率;移植瘤及心、肝、肾等组织HE染色,观察其病理变化;瘤组织免疫组化S-P法检测血管内皮生长因子（VEGF）表达、CD43标记的微血管密度MVD的表达。结果与对照组比较,As2O3组及ATRA组移植瘤生长明显受到抑制（质量抑瘤率分别为43．77％,41．82％）,两者联合用药后,抑制作用显著增强（质量抑瘤率为68．55％）,抑瘤率差异具有统计学意义（X2=26．81,P〈0．01）;As2O3组、ATRA组、联合用药组均不同程度下调VEGF表达（OD值分别为27．33±2．17,20．72±2．01,19．23±2．32,17．16±1．59）及MVD的表达（OD值分别为141．12±8．38,43．39±7．41,44．77±8．25,30．56±7．71）,联合用药组下调最显著;各用药组均出现轻度白细胞抑制（t=3．16,3．08,3．37,P〈0．01）,联合用药组抑制程度与单一用药组比较差异无统计学意义（P〉0．05）,肝、肾功能各指标比较差异均无统计学意义（P〉0．05）。结论ATRA联合As2O3在体内能够协同抑制膀胱癌BIU-87细胞移植瘤的生长和血管生成,仅有白细胞轻度抑制,对肝肾功能无毒副作用。     

Implanted tumor growth is suppressed and survival is prolonged in sixty percent of food-restricted mice

To examine the effect of food restriction on immune functions in the tumor-bearing state, mice were divided into a control group (fed 5.0 g diet/d; 71 kJ/d) and a 60% food-restricted group (fed 3.0 g diet/d; 43 kJ/d) at 8-wk of age, and 4 wk later, L1210 tumor cells were inoculated intradermally. In the food-restricted mice, tumor growth was significantly suppressed, and mean survival time after the tumor inoculation was prolonged (P < 0.05). The plasma concentrations of two antitumor cytokines, interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), were greater in the food-restricted group before tumor inoculation (P < 0. 05). Furthermore, the food-restricted mice had significantly higher plasma levels of IFN-gamma and TNF-alpha after tumor inoculation, although the treatment significantly increased these cytokine levels in both groups. Splenic natural killer cell cytotoxicity was also higher in the tumor-bearing food-restricted mice than in controls (P < 0.05). Food-restricted mice have strong antitumor immunity, and as a result, tumor growth is suppressed and survival time is prolonged in these mice.     

Effect of tumor weight and tube feeding on TNF-alpha and IL-1beta mRNA expression in the brain of mice.

BACKGROUND: Previous studies have shown that cytokine mRNA expression is elevated in the brains of anorectic, tumor-bearing rats. The objectives of the current study were as follows: (1) to determine whether a small tumor would result in up-regulation of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta mRNA expression in the brain and other tissues of tumor-bearing mice; and (2) to determine whether hyperalimentation by tube feeding would prevent up-regulation of cytokine mRNA expression in the brain and other tissues of tumor-bearing mice. METHODS: Male C57BL/6 mice were divided into 4 groups: (1) control mice fed ad libitum (Control); (2) tumor-bearing mice fed ad libitum (TB); (3) control mice receiving tube feeding (CTF); and (4) tumor-bearing mice receiving tube feeding (TBTF). RESULTS: TNF-alpha and IL-1beta mRNA expression was elevated in the brains of mice with a 1% body weight tumor, relative to the control and CTF groups, without any detectable changes in the other organs. On the other hand, TNF-alpha and IL-1beta mRNA expression was elevated in all organs of mice with an 8% body weight tumor, relative to the control and CTF groups. Tube feeding did not change TNF-alpha and IL-1beta mRNA expression in mice burdened with either a 1% or 8% body weight tumor. CONCLUSIONS: Up-regulation of cytokine mRNA synthesis occurs earlier in the brain than in other organs, and hyperalimentation does not change cytokine mRNA expression in tumor-bearing mice.     

荔枝草水提物联合X线放疗对结直肠癌细胞株荷瘤小鼠瘤组织的生长抑制作用

目的 观察荔枝草水提物（water extract of salvia plebeia,WESP）联合X线放疗对结直肠癌CT26细胞株荷瘤小鼠瘤组织生长的抑制作用。方法 建立结直肠癌CT26细胞荷瘤小鼠模型,分为空白对照组、阳性对照组（腹腔注射氟尿嘧啶30 mg/kg）、WESP组（灌胃WESP 500 mg/kg）、放疗组（2 Gy X线照射）和WESP + 放疗组（灌胃WESP 500 mg/kg + 2 Gy X线照射）,每组10只。各组小鼠每日给药1次,连续21 d;放疗组及WESP + 放疗组在给药期间每5 d放疗1次。于给药后第0、7、14及21 d测量移植瘤体积;末次测量瘤体积后,取瘤组织称重;采用RT-PCR和Western blot法测定瘤组织VEGF、Survivin mRNA和蛋白表达水平。结果 与空白对照组比较,其他3组小鼠第7、14及21 d移植瘤体积增长降低,瘤重减轻,瘤组织VEGF、Survivin mRNA与蛋白表达水平下调;与阳性对照组比较,WESP 组和放疗组小鼠第7、14及21 d瘤体积增长较快,瘤重增加,瘤组织VEGF、Survivin mRNA与蛋白表达水平上调。结论 荔枝草水提物与X线放疗合用对结直肠癌生长具有抑制作用,其机制与下调VEGF、Survivin表达有关。     

碳酸镧在CA、UDS和MN试验中的抗诱变作用

应用人胚纤维母细胞（ＨＥＦ）染色体畸变（ＣＡ）试验、非程序ＤＮＡ合成（ＵＤＳ）试验和小鼠骨髓细胞微核（ＭＮ）试验，研究了碳酸镧对短波紫外线（ＵＶ）、盐酸氮芥（ＮＨ２ＨＣ１）、亚砷酸钠（ＮａＡｓＯ２）和环磷酰胺（ＣＰ）致突变作用的影响，从遗传学角度评估了碳酸镧的抗诱变作用。结果表明：碳酸镧在ＵＶ、ＮＨ２ＨＣｌ和ＣＰ诱导的不同遗传终点中，显示了不同程度的诱变抑制作用。但碳酸镧对ＮａＡｓＯ２诱导的ＣＡ效应仅有下降趋势，而无统计学意义，故认为其抗诱变作用可能有某种专属性。     

碳酸镧在CA,UDS和MN试验中抗诱变作用

应用人胚纤维母细胞染色体畸变试验，非程序合成试验和小鼠骨髓细胞微核试验，研究了碳酸镧对短波紫外线，盐酸氮芥，亚砷酸钠和环磷酰胺致突变作用的影响，从遗传学角度评估了碳酸镧的抗诱变作用。     

果蔬发酵液体内外的抑癌作用及对免疫功能的影响

目的研究果蔬发酵液(VFFL)的抑瘤作用及对免疫功能的保护作用。方法采用ICR小鼠建立移植性肝癌小鼠模型,随机分为阴性对照组、阳性对照组和VFFL16.6、33.36、6.6 ml/(kg.d)三个剂量组,观察小鼠的瘤重、脾指数、胸腺指数;流式细胞仪检测细胞凋亡;MTT法检测VFFL对SMMC-7721肝癌细胞增殖的抑制作用并用吖啶橙染色于荧光显微镜观察细胞核形态学变化并检测淋巴细胞转化能力、NK细胞活性。结果VFFL各剂量组对H22肿瘤细胞均有明显的抑制作用,抑制率为49.1%、35.0%和25.7%并可显著诱导细胞凋亡;VFFL作用3 d后呈剂量依赖性抑制SMMC-7721细胞增殖,5 d后作用显著,荧光显微镜下细胞核固缩、凝聚,呈浓染致密的颗粒块状并明显提高小鼠NK细胞活力(P<0.01)。结论VFFL具有抑制肿瘤细胞生长作用,其可能与诱导细胞凋亡及提高小鼠机体免疫功能有关。     

JP-8 jet fuel exposure potentiates tumor development in two experimental model systems

The US Air Force has implemented the widespread use of JP-8 jet fuel in its operations, although a thorough understanding of its potential effects upon exposed personnel is unclear. Previous work has reported that JP-8 exposure is immunosuppressive. Exposure of mice to JP-8 for 1 h/day resulted in immediate secretion of two immunosuppressive agents; namely, interleukin-10 (IL-10) and prostaglandin E2 (PGE2). Thus, it was of interest to determine if jet fuel exposure might promote tumor growth and metastasis. The syngeneic B16 tumor model was used for these studies. Animals were injected intravenously with tumor cells, and lung colonies were enumerated. Animals were also examined for metastatic spread of the tumor. Mice were either exposed to 1000 mg/m3 JP-8 (1 h/ day) for 7 days before tumor injection or were exposed to JP-8 at the time of tumor injection. All animals were killed 17 days after tumor injection. In the present study, JP8 exposure potentiated the growth and metastases of B16 tumors in an animal model. Exposure of mice to JP-8 for 1 h/day before tumor induction resulted in an approximately 8.7-fold increase in tumors, whereas those mice exposed to JP8 at the time of tumor induction had a 5.6-fold increase in tumor numbers. Thus, low concentration JP-8 jet fuel exposures have significant immune suppressive effects on the immune system that can result in increased tumor formation and metastases. We have now extended the observations to an experimental subcutaneous tumor model. JP8 exposure at the time of tumor induction in this model did not affect the growth of the tumor. However, JP8-exposed, tumor-bearing animals died at an accelerated rate as compared with air-exposed, tumor-bearing mice.