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11.
Strong adjuvant action of Klebsiella O3 lipopolysaccharide and its inhibition of systemic anaphylaxis 总被引:1,自引:0,他引:1
T. Yokochi Y. Inoue Y. Kato T. Sugiyama G.-Z. Jiang M. Kawai M. Fukada K. Takahashi 《FEMS immunology and medical microbiology》1995,10(3-4):181-184
Abstract Immunization with lipopolysaccharide from Klebsiella O3 as an immunological adjuvant did not cause the death of mice in systemic anaphylaxis to bovine serum albumin. On the other hand, most mice immunized with lipopolysaccharide from Escherichia coli O111, Klebsiella O4 and Salmonella minnesota did die. Klebsiella O3 lipopolysaccharide enhanced IgM and IgG antibody response to BSA more markedly than Escherichia coli O111 lipopolysaccharide, while it affected the production of IgE antibody only slightly. Therefore, it is suggested that the inhibition of systemic anaphylaxis by Klebsiella O3 lipopolysaccharide adjuvant might be related to its strong adjuvant action on IgM and IgG class antibody production, and that high levels of circulating IgM and IgG antibodies might act as blocking antibodies in the development of IgE-mediated systemic anaphylaxis. 相似文献
12.
R. J. Bernacki M. Sharma N. K. Porter Y. Rustum B. Paul W. Korytnyk 《Journal of cellular biochemistry》1977,7(2):235-250
We have synthesized several potential inhibitors and/or modifiers of the carbohydrate portion of plasma membrane glycoconjugates. These include fluorinated and actylated analogs of D-glucosamine, D-galactosamine, and D-mannosamine. These compounds have been tested to determine their effects on both [14C] glucosamine and [3H] leucine incorporation into glycoconjugate and on cell growth and viability using P-288 murine lymphoma cells maintained in tissue culture. The most cytotoxic agent tested was 2-acetamido-2-deoxy-1,3,4,6-tetra-O-acetyl-β-D-glucopyranose or simply β-pentaacetylglucosamine which prevented cell growth at 10?4–10?3 M. β-Pentaacetylglucosamine cytotoxicity was correlated with its high lipid solubility, having an octanol/water partition coefficient of 0.424 as compared with 0.278 for the β-anomer and 0.017 for N-acetylglucosamine. In vitro metabolism studies with [14C]-and/or [3H]-labeled pentaacetylglucosamine have indicated intracellular de-O-acetylation leading to the biosynthesis of UDP-N-acetylglucosamine, followed by the incorporation of this sugar into cellular glycoprotein. Concomitant with the formation of increased amounts of this nucleotide sugar, intracellular UTP and CTP pools fell to one third normal within 3 h after the administration of 1 mM pentaacetylglucosamine. At present it is unclear whether the cytotoxicity of β-pentaacetylglucosamine or other similar agents is due to alterations in nucleotide and nucleotide-sugar pools causing a decrease in energy charge and polynucleotide biosynthesis or is due to a direct effect on membrane glycoconjugate biosynthesis. 相似文献
13.
抑制O~6-甲基鸟嘌呤-DNA甲基转移酶活性与肿瘤细胞对亚硝脲药物敏感性关系的研究 总被引:1,自引:0,他引:1
80%以上的肿瘤细胞为O~6-甲基鸟嘌吟-DNA甲基转移酶(O~6-MT)活性较高的Mer~+型,能够修复亚硝脲药物(NU)造成的DNA烷化损伤,对NU不敏感。本实验证明,用0.75,0.50和0.25mmol/L甲基亚硝脲(MNU)分别处理Mer~+型的HeLaS3,SMMC-7721和表现Mer~-型特征的Cc801,均能明显降低细胞中O~6-MT活性,从而显著提高了三种细胞对嘧啶亚硝脲和双氯乙亚硝脲的敏感性,提示降低O~6-MT活性是使用NU对Mer~+型肿瘤进行有效治疗的前提。 相似文献
14.
F W Jennings D D Whitelaw P H Holmes H G Chizyuka G M Urquhart 《International journal for parasitology》1979,9(4):381-384
During the aparasitaemic period following chemotherapy of all three strains of T. brucei infections in mice, successful transmission as shown by subsequent parasitaemia, was regularly achieved following the inoculation of homogenates of brain tissue into recipient mice. Transmission with blood obtained at the same time was consistently negative and in the case of T. brucei TREU 667, homogenates of other organs were non-infective. The implications of this central nervous system involvement are discussed with particular reference to its use as a model for relapsing infections after therapy in man. 相似文献
15.
Rajagopalan Sridhar Eric C. Stroude W. Rodger Inch 《In vitro cellular & developmental biology. Plant》1979,15(9):685-690
Summary 2-Deoxy-d-glucose (2DG) and 5-thio-d-glucose (5TG) are glucose antimetabolites that are known to be selectively toxic to hypoxic cells grown as single cells or
as monolayer cultures. These analogues were toxic to Chinese hamster V79 cells grown as multicell spheroids even under aerobic
conditions. When spheroids, 500- to 600-μm diameter, were exposed to 7.5mm of these chemicals for 3 days, the number of clonogenic cells per spheroid dropped to 50% for 5-thio-d-glucose and 20% for 2-deoxy-d-glucose, relative to control values. Survivals were reduced to less than 1% when the experiment was repeated in glucose-free
medium. Scanning electron photomicrographs of spheroids treated with 7.5mm of either analogue showed extensive damage to the outer cells. The cell killing observed was much more than could be predicted
on the basis of the hypoxic fraction known to be present in these spheroids. The crowded tumor-like environment may make the
cells vulnerable to the cytotoxic action of glucose analogues and other glycolytic inhibitors.
Supported by the Ontario Cancer Treatment and Research Foundation, London Clinic. 相似文献
16.
免疫疗法是预防和治疗疾病的有效手段之一.近年来,肿瘤免疫疗法已成为一种新型治疗方法,相关肿瘤疫苗已在多种肿瘤的治疗中被证明有效.然而,在肿瘤疫苗的设计中,肿瘤抗原免疫原性弱,应答率低等问题是目前面对的一大挑战,佐剂的加入为问题的解决提供了一种新的方法和思路.免疫佐剂在提高肿瘤抗原免疫原性,激活机体适应性免疫应答等方面起着十分重要的作用.为了解近几年免疫佐剂的发展及其研究现状,针对目前常用的抗肿瘤佐剂进行综述,并总结了其对免疫系统的作用机制,为后续的疫苗设计策略提供帮助. 相似文献
17.
18.
Rui Zhou Huiying Sun Siting Zheng Jingwen Zhang Dongqiang Zeng Jianhua Wu Zhenhua Huang Xiaoxiang Rong Jianping Bin Yulin Liao Min Shi Wangjun Liao 《Journal of cellular and molecular medicine》2020,24(5):3229-3241
The heterogeneity in prognoses and chemotherapeutic responses of colon cancer patients with similar clinical features emphasized the necessity for new biomarkers that help to improve the survival prediction and tailor therapies more rationally and precisely. In the present study, we established a s troma-related l ncRNA s ignature (SLS) based on 52 lncRNAs to comprehensively predict clinical outcome. The SLS model could not only distinguish patients with different recurrence and mortality risks through univariate analysis, but also served as an independent factor for relapse-free and overall survival. Compared with the conventionally used TNM stage system, the SLS model clearly possessed higher predictive accuracy. Moreover, the SLS model also effectively screened chemotherapy-responsive patients, as only patients in the low-SLS group could benefit from adjuvant chemotherapy. The following cell infiltration and competing endogenous RNA (ceRNA) network functional analyses further confirmed the association between the SLS model and stromal activation-related biological processes. Additionally, this study also identified three phenotypically distinct colon cancer subtypes that varied in clinical outcome and chemotherapy benefits. In conclusion, our SLS model may be a significant determinant of survival and chemotherapeutic decision-making in colon cancer and may have a strong clinical transformation value. 相似文献
19.
Hao Xu Shangjun Wu Xin Shen Zhan Shi Ding Wu Yuan Yuan Wei Jiang Qianliang Wang Qin Ke Qing Mao Xianlong Li Yong Liu Pingcheng Yuan Qinghan Zhang Enying Huang Xiaogang Chen 《Journal of cellular and molecular medicine》2020,24(11):6410-6425
LIVIN, a member of the inhibitor of apoptosis proteins (IAPs), is reported playing important roles in the development and progression of multiple human cancers. However, its underlined mechanisms in human renal cell carcinoma (RCC) are still needed to be clarified. In the present study, we reported that inhibition of miR-214 promoted the expression of LIVIN, then facilitated RCC cells growth and reduced the sensitivity of RCC cells to chemotherapeutic drugs. In constant, overexpression of miR-214 had contradictory effects. Further investigation showed that miR-214 was down-regulated in RCC because of abnormal methylation. In addition, DNA methyltransferase DNMT1, miR-214 and LIVIN are directly correlated in RCC patients. In conclusion, these results suggest that abnormal miR-214 methylation negatively regulates LIVIN, which may promote RCC cells growth and reduced the sensitivity of RCC cells to chemotherapeutic drugs. 相似文献
20.
摘要 目的:探讨消癌平注射液联合表柔比星新辅助化疗对三阴性乳腺癌(TNBC)患者免疫功能、生活质量及血清肿瘤标志物的影响。方法:选取TNBC患者89例,按照随机数字表法分为对照组和研究组,对照组(n=44)患者给予表柔比星新辅助化疗治疗,研究组(n=45)患者给予消癌平注射液联合表柔比星新辅助化疗。对比两组疗效、免疫功能、生活质量、血清肿瘤标志物及不良反应。结果:研究组治疗12周后的临床总有效率为91.11%(41/45),高于对照组的63.64%(28/44)(P<0.05)。两组治疗12周后健康调查简表(SF-36)量表各维度评分升高,且研究组较对照组高(P<0.05)。两组治疗12周后CD4+CD25+Treg、Th17/ Treg均降低,且研究组较对照组低(P<0.05),Th17升高,且研究组较对照组高(P<0.05)。两组治疗12周后癌胚抗原(CEA)、糖类抗原199(CA199)、糖类抗原125(CA125)均降低,且研究组较对照组低(P<0.05)。两组不良反应发生率对比未见差异(P>0.05)。结论:消癌平注射液联合表柔比星新辅助化疗治疗TNBC,具有确切的治疗效果,可降低血清肿瘤标志物水平,改善患者免疫功能和生活质量。 相似文献