芦荟多糖对正常细胞株和肿瘤细胞株辐射防护作用的差异性

芦荟多糖(Aloe Polysaccharides, AP)是从中华芦荟提取得到的粗多糖,研究表明其对辐射动物具有显著的保护作用[1],对非瘤细胞辐射后细胞凋亡及凋亡蛋白的表达也有显著调节作用[2].本文观察AP对正常细胞株和肿瘤细胞株的辐射防护作用是否具有差异性.     

中药多糖对免疫调节作用的研究进展

本文从免疫器官、细胞及分子等水平上对40多年来对中药多糖的免疫调节作用研究进行了综合分析，进一步揭示中药多糖可从多系统、多器官、多细胞、多靶点等层次发挥其免疫调节作用。     

中药多糖抗肿瘤作用研究进展

本文主要从多糖提高宿主免疫功能,对肿瘤细胞的直接作用以及其构效关系对中药多糖抗肿瘤作用研究进展作一综述。     

中药多糖抗肿瘤作用研究进展

本文主要从多糖提高宿主免疫功能,对肿瘤细胞的直接作用以及其构效关系对中药多糖抗肿瘤作用研究进展作一综述.     

中药多糖抗肿瘤作用研究进展

本文主要从多糖提高宿主免疫功能,对肿瘤细胞的直接作用以及其构效关系对中药多糖抗肿瘤作用研究进展作一综述。     

冬灵菌丝体多糖合剂对小鼠的辐射防护和对外周血白细胞数量的影响

冬虫夏草为传统的滋补强壮药，其主要成份虫草菌丝多糖的药理作用和天然虫草相似，均具有降血脂，抗炎．止咳，镇静等作用，但抗肿瘤作用较弱”］，而虫草多糖加灵芝多糖制成的冬灵菌丝体多糖合剂，贝IJ又寸小鼠518。肉瘤及BI6－MB黑色素瘤有明显的抑癌作用D］，对巨噬细胞吞噬功能具有明显的激活作用。本文拟在此基础上，进一步研究冬灵菌丝体多糖合剂对钻‘’r射线辐射的防护及升白作用。实验材料1．药物：冬灵菌丝体多糖合剂由我室自制，按K。rbef氏法，lP给药的LDS。为19．429／kg，95％可信阳为17．Zg／kg～21．879／kg。香茹多…     

甘草多糖药理学作用研究进展

甘草多糖是豆科植物甘草的主要成分之一.经研究表明,甘草多糖的药理作用广泛,在免疫调节,抗氧化,抗肿瘤、抑菌、抗炎和肠道菌群调节方面发挥重要作用.本文通过检索近些年国内外有关甘草多糖的研究报道,对其药理学作用及机制的研究进展进行综述,为甘草多糖日后的开发及临床应用提供参考.     

石花多糖对辐射损伤小鼠防护作用的研究

目的研究地衣类石花多糖对辐射损伤小鼠造血功能及DNA损伤的防护作用。方法用内源性脾结节形成(CFU-S),骨髓有核细胞计数(BMNC),脾脏指数观察石花多糖50,80 mg/kg腹腔注射对137Csγ射线照射小鼠造血功能的影响;单细胞凝胶电泳(SCGE)技术检测小鼠淋巴细胞照射后的DNA双链断裂,观察给药后小鼠DNA损伤修复情况。结果照射前连续给药3 d,照后第7天受照小鼠的BMNC、CFU-S和脾指数与对照组相比有明显的增高;SCGE中各项指标显示,给药组的DNA损伤的修复明显增加,呈明显的量-效关系。结论石花多糖对辐射损伤小鼠具有良好的辐射防护作用。     

辐射防护相关信号通路研究现状

人们在生活中接触到各种辐射,长期或者大剂量的辐射能够导致组织损伤,其机制通常与细胞凋亡、坏死、炎症等相关。目前关于辐射防护的研究越来越多,其中涉及多条通路,代表性的通路有：NFκB通路、MAPK通路、PI3K/Akt通路、p53通路以及STAT3通路。笔者综述了上述通路在辐射防护领域的作用与研究现状。     

Dose Response of MTLn3 Cells to Serial Dilutions of Arsenic Trioxide and Ionizing Radiation

MTLn3 cells derived from mouse mammary epithelium are known to be highly malignant and are resistant to both radio- and chemo-therapy. We exposed MTLn3 cells to various doses of inorganic Arsenic trioxide (As₂O₃) in combination with ionizing radiation. Cells were treated with a series of As₂O₃ concentrations ranging from 20 μM to 1.22 nM for 8 hour, 24 hour and 48 hour periods. Post-treated cell proliferation was quantified by measuring mitochondrial activity and DNA analysis. Cells exposed to radiation and As₂O₃ at concentration greater than 1.25 μM showed apoptosis and radiations alone treated cells were statistically not different from the control. Hormesis was observed for As₂O₃ concentrations in the range of 0.078 μM to 0.625 μM while the combined chemo and radiation treatments of the cells did not affect the hormetic effect. We have demonstrated that As₂O₃ (in the presence and absence of ionizing radiation) in specific low concentrations induced apoptosis in the otherwise chemoresistant cancer cells. This low concentration-mediated cell death is immediately followed by a surge in cell survival. Low dosing dosimetry is highly desirable in metronomic therapy however, it has a narrow window since necrosis, hormesis, apoptosis and other dose-dependent biological processes take place in this region. Further quantifiable dosimetry is highly desired for routine clinical practice.     

脉冲场凝胶电泳检测电离辐射诱发DNA损伤及其修复

目的：评价脉冲场凝胶电泳（PFGE）法检测电离辐射诱发小鼠脾细胞DNA损伤及其修复的可行性.方法：采用PFGE法测定不同剂量γ射线诱发小鼠脾细胞DNA单、双链断裂及4 Gyγ射线照射后不同时间脾细胞DNA单、双链断裂及其修复情况,并与未照射组（对照组）进行比较.结果：γ射线照射小鼠后,脾细胞DNA单、双链断裂数目随照射剂量的增加均呈增加趋势,单链断裂数目多于双链,1 Gy所致DNA双链断裂及2 Gy所致DNA单链断裂显著高于对照组（t=2.668,P＜0.05;t=5.117,P＜0.01）.以4 Gy照射后经过不同时间修复,单、双链断裂均呈下降趋势,起初DNA链断裂的修复为快速修复,1 h后大多数损伤已得到修复.单链断裂的修复速度高于双链,当修复时间超过2 h后,单链断裂又呈现上升趋势.结论：本实验方法有可能成为一种快速、敏感地检测活体动物细胞DNA损伤及其修复的方法.     

药物中有关物质检测方法的研究进展及应用

摘 要 当前药物安全性问题已成为全社会越来越关注的焦点,而有关物质研究及控制是药品安全保证的关键要素之一,各国药品质量标准对有关物质检查的要求也越来越高。因此,对药物中有关物质进行检测和控制也显得极为重要。本文针对近年来药物中有关物质检查的分析技术及其应用进行综述,为药物质量控制提供参考。     

黄芪多糖对电离辐射诱发间充质干细胞基因DNA损伤的保护作用

目的 研究黄芪多糖(Astragalus polysaccharide,APS)对X射线辐照人骨髓间充质干细胞(human bone mesenchymal stem cells,HMSC-bm)增殖水平影响及其诱发DNA损伤的保护作用。方法 采用CCK-8法筛选APS作用于HMSC-bm细胞的最佳有效浓度;照射组采用2.0 Gy剂量X射线辐照干预HMSC-bm,加药组用最佳药物浓度干预受辐照HMSC-bm：CCK-8法检测各组细胞的增殖能力;胞质分裂阻滞微核技术(CB微核法)检测X射线照射HMSC-bm后的微核率;免疫荧光检测53BP1免疫荧光簇集焦点。结果 APS浓度为50 μg·mL^-1时促增殖作用最高,设为最佳药物浓度,与对照组(0 μg·mL^-1 APS)相比,其促增殖作用具有统计学差异(P<0.05);与对照组比较,X射线照射后细胞增殖水平明显降低(P<0.05)。与单纯照射组比较,加药照射组HMSC-bm细胞增殖水平显著增加(P<0.05),其增殖水平接近对照组细胞增殖水平;单纯照射组0.5,2 h细胞内53BP1免疫荧光焦点显著增多(P<0.05),而给药显著降低了辐射诱导的53BP1焦点水平(P<0.05);照射后细胞微核率明显升高(P<0.05),给药则导致细胞微核率显著降低(P<0.05)。结论 APS对X射线辐射诱发人骨髓间充质干细胞基因组DNA损伤有防护作用。     

小檗碱治疗高脂血症研究进展

随着近年血脂异常患者逐渐增加,高脂血症备受关注。现代药理学证实,传统中药小檗碱具有温和的降血脂作用,其作用机制独特,毒副作用小,临床不良反应少,且价低易得,具有现有降脂类药物不可比拟的优势。本文就小檗碱的降血脂药理作用、作用机制、药代动力学、毒理学及临床应用方面进行概括性综述,结果表明小檗碱治疗高脂血症药效明确,毒副作用小,在高脂血症及相关疾病的治疗中前景广阔。     

辐射防护与辐射治疗剂临床应用及进展

目的：探讨辐射防护与辐射治疗剂的临床应用及进展。方法：通过查阅最新的研究文献，对辐射防护与辐射治疗剂的临床应用及进展进行归纳、综述。结果：辐射防护与辐射治疗剂有：氨磷汀、蛋白酶抑制剂、激素类抗放射药、天然药物、细胞因子和间充质干细胞等；其中，细胞因子和间充质干细胞作为辐射防护与辐射治疗剂的研究在国内外备受关注。结论：辐射防护与辐射治疗剂的临床应用有了新的进展，为核事故临床救治提供了新的治疗依据。     

Commentary: Ethical Issues of Current Health-Protection Policies on Low-Dose Ionizing Radiation

The linear no-threshold (LNT) model of ionizing-radiation-induced cancer is based on the assumption that every radiation dose increment constitutes increased cancer risk for humans. The risk is hypothesized to increase linearly as the total dose increases. While this model is the basis for radiation safety regulations, its scientific validity has been questioned and debated for many decades. The recent memorandum of the International Commission on Radiological Protection admits that the LNT-model predictions at low doses are “speculative, unproven, undetectable and ‘phantom’.” Moreover, numerous experimental, ecological, and epidemiological studies show that low doses of sparsely-ionizing or sparsely-ionizing plus highly-ionizing radiation may be beneficial to human health (hormesis/adaptive response). The present LNT-model-based regulations impose excessive costs on the society. For example, the median-cost medical program is 5000 times more cost-efficient in saving lives than controlling radiation emissions. There are also lives lost: e.g., following Fukushima accident, more than 1000 disaster-related yet non-radiogenic premature deaths were officially registered among the population evacuated due to radiation concerns. Additional negative impacts of LNT-model-inspired radiophobia include: refusal of some patients to undergo potentially life-saving medical imaging; discouragement of the study of low-dose radiation therapies; motivation for radiological terrorism and promotion of nuclear proliferation.     

荞麦多糖的研究进展

多糖是从动、植物中分离出的一类物质,在免疫调节、抗肿瘤、抗病毒和抗感染等方面有很强的活性,疗效高、毒副作用小,值得深入研究和开发。本文就荞麦多糖的提取纯化、化学结构、分子量测定、生物活性等方面的研究进展予以综述。     

硫酸化多糖抗肿瘤研究进展

摘 要硫酸化多糖是糖羟基上含有硫酸根的多糖,可经天然提取或硫酸化的化学修饰而得到。近年的研究证明硫酸化多糖呈现了不同程度的抗肿瘤活性,尤其是与化学修饰前相比其抗肿瘤活性显著增强,引起广泛的关注。本文对近几年国内外与天然硫酸化多糖和化学合成硫酸化多糖抗肿瘤活性相关的研究进行综述。     

Adaption By Low Dose Radiation Exposure: A Look at Scope and Limitations for Radioprotection

The procedures and dose limitations used for radiation protection in the nuclear industry are founded on the assumption that risk is directly proportional to dose, without a threshold. Based on this idea that any dose, no matter how small, will increase risk, radiation protection regulations generally attempt to reduce any exposure to “as low as reasonably achievable” (ALARA). We know however, that these regulatory assumptions are inconsistent with the known biological effects of low doses. Low doses induce protective effects, and these adaptive responses are part of a general response to low stress. Adaptive responses have been tightly conserved during evolution, from single celled organisms up to humans, indicating their importance. Here we examine cellular and animal studies that show the influence of radiation induced protective effects on diverse diseases, and examine the radiation dose range that is effective for different tissues in the same animal. The concept of a dose window, with upper and lower effective doses, as well as the effect of multiple stressors and the influence of genetics will also be examined. The effect of the biological variables on low dose responses will be considered from the point of view of the limitations they may impose on any revised radiation protection regulations.