大豆异黄酮对电离辐射小鼠淋巴细胞的防护作用

目的研究大豆异黄酮(SI)对小鼠淋巴细胞的辐射防护作用。方法24只雄性昆明小鼠,随机分为正常对照组、辐射对照组和辐射补充0.5%SI组,喂养2周后,4.0Gy照射。照射后24 h处死小鼠,取血、胸腺和脾脏分离淋巴细胞,进行血淋巴细胞计数、观察DNA损伤情况;培养胸腺和脾脏淋巴细胞,检测3H-dT掺入量,观察淋巴细胞的增殖能力,计算淋巴细胞的增殖指数。结果辐射使小鼠胸腺和脾脏淋巴细胞数明显减少、胸腺淋巴细胞增殖能力和脾脏淋巴细胞转化指数降低、血淋巴细胞DNA损伤增加,这些变化均具有统计学意义;补充SI可降低胸腺和脾脏淋巴细胞数的减少幅度,降低胸腺淋巴细胞增殖能力和脾脏淋巴细胞转化指数下降幅度,减少辐射对血淋巴细胞DNA损伤程度,其中SI对胸腺淋巴细胞增殖能力和对血淋巴细胞DNA损伤程度的防护作用与辐射对照组相比有统计学意义。结论大豆异黄酮可对小鼠的血、胸腺和脾脏淋巴细胞有一定的辐射防护作用。     

大蒜素对白色念珠菌感染小鼠神经内分泌免疫系统调节作用的研究(英文)

本研究旨在探讨大蒜素对白色念珠菌感染小鼠神经内分泌免疫系统(NEI)的调节作用。将小鼠随机分为三组:正常对照组、模型组、大蒜素组。除正常对照组外,模型组、大蒜素组分别建立小鼠白色念珠菌感染模型。大蒜素组小鼠给予大蒜素灌胃,其余组给予等量生理盐水。连续用药14 d后,各组小鼠取血测定促肾上腺激素(ACTH)、皮质酮(CORT)、β-内啡肽(β-EP)、5-羟色胺(5-HT)的水平,测定胸腺指数及脾脏淋巴细胞增殖活性。实验结果显示,模型组小鼠NEI功能发生紊乱,与正常对照组相比,ACTH、CORT、β-EP水平均明显升高,5-HT、胸腺指数及脾脏淋巴细胞增殖活性均明显下降,差异有显著性(P<0.05)。而大蒜素组小鼠ACTH、CORT、β-EP水平较之模型组明显下降,5-HT、胸腺指数及脾脏淋巴细胞增殖活性明显升高,差异有显著性(P<0.05)。综上所述,本研究提示大蒜素对白色念珠菌感染小鼠紊乱的NEI具有明显的调节作用。     

X线全身照射对2型糖尿病KKAy小鼠造血免疫系统功能的影响

目的观察X线全身照射对2型糖尿病模型KKAy小鼠的造血免疫系统功能的损伤作用,并与对照C57小鼠进行比较。方法KKAy小鼠,分为对照组和照射组,照射组小鼠经X线全身照射,剂量4Gy,C57小鼠作为对照。照射后15d检测小鼠的外周血常规,流式细胞术检测骨髓中造血祖细胞、造血干细胞和长期造血干细胞的比例,脾中B细胞和T细胞的比例,胸腺中CD4CD8双阳性T细胞、CD4单阳性T细胞和CD8单阳性T细胞的比例。通过粒细胞集落形成能力实验评价小鼠造血祖细胞的功能。结果照射前KKAy小鼠的HSC和LT-HSC的比例低于C57小鼠。4Gy全身照射后,KKAy小鼠的外周血WBC、RBC、PLT、HGB和LYM%分别下降了68.42%、12.17%、8.78%、30.12%、70.84%;骨髓中HPC、HSC和LT-HSC的比例分别下降了34.02%、29.49%、35.74%;脾B细胞和T细胞的比例分别下降了57.85%、58.81%;胸腺CD4CD8双阳性细胞的比例下降了51.70%。KKAy小鼠的骨髓HSC、LT-HSC、外周血RBC和HGB的降低幅度显著低于C57小鼠。结论4Gy全身照射损伤KKAy小鼠的造血免疫系统功能,KKAy小鼠可能比C57小鼠表现出对电离辐射较强的耐受性。     

唐古特大黄多糖组分1对急性电离辐射损伤小鼠的保护作用

目的：探讨唐古特大黄多糖组分1（RTP1）对急性电离辐射损伤小鼠的保护作用。方法：采用昆明种小鼠,随机分为5组：正常对照组（Normal Control,NC）、辐射对照组（Irradiation Control,IC）以及RTP1低剂量组（200 mg/kg）、中（400 mg/kg）和高剂量组（800 mg/kg）,采用灌胃给药方式,连续14 d,NC组和IC组则给予等量的生理盐水,第14 d除NC组外,各组小鼠均接受2.0 Gy/只60Coγ射线照射1次,照射后24 h,检测小鼠胸腺和脾脏指数,测定肝脏超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH-Px）活性及丙二酰二醛（MDA）水平以及小鼠外周血象和骨髓嗜多染红细胞（PCE）微核数。结果：RTP1能够升高小鼠的胸腺、脾脏指数,增加肝脏SOD和GSH-Px活性,降低MDA水平,升高外周血中白细胞数并降低骨髓PCE微核数,与IC组比较有统计学意义（P〈0.05或P〈0.01）。结论：RTP1对辐射所致的小鼠损伤具有一定的保护作用。     

恒定磁场对小鼠免疫功能的影响

目的:从免疫学方面探讨不同照射时间的恒定磁场对小鼠免疫功能的影响。方法:用同一强度不同照射时间的恒定磁场(2小时恒定磁场照射组、3小时恒定磁场照射组、4小时恒定磁场照射组和无磁场照射的正常对照组)对小鼠进行照射,连续20天,每天一次,末次12小时后称其体重,取出胸腺、脾脏、肝脏,称重,计算各器官指数。结果:与正常对照组比较,三组同一强度不同照射时间的恒定磁场组对小鼠的胸腺指数有显著的降低(p<0.05);2小时组与3小时组的肝脏指数也有显著的降低(p<0.05);对脾脏指数无显著影响(p>0.05)。结论:一定照射时间的恒定磁场对小鼠的免疫功能具有抑制作用。     

恒定磁场对小鼠免疫功能的影响

目的：从免疫学方面探讨不同照射时间的恒定磁场对小鼠免疫功能的影响。方法：用同一强度不同照射时间的恒定磁场（2小时恒定磁场照射组、3小时恒定磁场照射组、4小时恒定磁场照射组和无磁场照射的正常对照组）对小鼠进行照射,连续20天。每天一次,末次12小时后称其体重,取出胸腺、脾脏、肝脏,称重,计算各器官指数。结果：与正常对照组比较,三组同一强度不同照射时间的恒定磁场组对小鼠的胸腺指数有显著的降低（p〈0．05）;2小时组与3小时组的肝脏指数也有显著的降低（p〈0．06）;对脾脏指数无显著影响（p〉0．05）。结论：一定照射时间的恒定磁场对小鼠的免疫功能具有抑制作用。     

沙棘Vp对辐射损伤小鼠的保护及免疫功能作用研究

本文探讨了沙棘Vp对X射线辐射损伤小鼠的保护作用。将150只昆明种小白鼠分为正常对照组、阳性对照组、辐射对照组、沙棘Vp高、中、低剂量组,雌雄各半,除了正常对照组外,其余各组小鼠接受5Gy的X射线一次性的全身均匀照射。检查各小组小鼠外周血中红细胞数、白细胞数,血小板数,测定超氧化物歧化酶的活力,丙二醛水平,小鼠单核巨噬细胞吞噬功能,小鼠血清溶血素生成能力,计算胸腺和脾脏的脏器指数。结果显示沙棘Vp对辐射后的小鼠血象有明显回升(P0.05),超氧化物歧化酶的活力显著增强(P0.05),丙二醛水平下降(P0.05),胸腺和脾脏的脏器指数升高(P0.05),并且显著提高小鼠血清溶血素生成能力,增强小鼠单核巨噬细胞吞噬功能。本研究说明,沙棘Vp对X射线辐射损伤小鼠具有一定的增强免疫及保护作用。     

小鼠低剂量辐射损伤模型的初步研究

目的:对小鼠低剂量辐射损伤模型进行初步研究并筛选敏感检测指标.方法:实验分7组,1组为正常组,其余6组用XHA600直线加速器射线照射,每组取一部分小鼠于照射后2、4、8、16h测定红细胞(RBC)、白细胞(WBC)、血小板(PLT)和血红蛋白(HGB)含量;测定小鼠肝脏和脾脏重量及其组织中的超氧化合物歧化酶(SOD)和丙二醛(MDA)含量;剩余小鼠于4周后观察骨髓切片中血细胞变化.结果:照射后4h测定血常规,发现累积辐射0.4Gy组小鼠RBC有降低趋势,WBC、HGB显著降低,PLT显著升高;肝脏、脾脏的湿质量显著降低;小鼠肝脏组织中MDA的含量显著升高、SOD的活力显著降低;4周后小鼠骨髓细胞的病理改变与单次照射剂量相关,单次较大剂量(如0.6Gy)照射对骨髓细胞影响较大,在4周观察期不能自身恢复,而多次累积照射对骨髓细胞病理改变较小.结论:小鼠低剂量辐射损伤模型的最佳造模剂量为累积照射0.4Gy即每次照射100mGy,间隔一天,连续照射4次.     

转基因MSC对放射损伤胸腺组织修复的研究

目的：探讨转基因MSC能否修复放射损伤的胸腺。方法：雌性BALB/C小鼠120只,随机分为4组：对照组30只,予以假照射;照射组30只,60Coγ射线胸腺单次照射,剂量为9Gy;照射＋MSC组30只,9Gy照射后2小时输注转基因MSC;对照＋MSC组30只,假照射后2小时输注转基因MSC。照射后1、7、14、21、28天检测各组小鼠血像、胸腺指数及胸腺病理。结果：照射＋MSC组血像和胸腺指数在各个时间点均优于照射组,胸腺病理显示组织结构恢复明显加快。结论：转基因MSC能归巢至放射损伤胸腺并能促进胸腺的修复,为干细胞的临床应用提供了实验依据。     

海藻酸钠寡糖对小鼠免疫及 抗氧化功能的影响

目的研究海藻酸钠寡糖对小鼠免疫及抗氧化活性的影响。方法采用不同浓度的海藻酸钠寡糖分别对小鼠连续灌胃15d后,测量小鼠生长性能、小鼠胸腺和脾脏指数以及小鼠血浆中SOD和GSH的活性。结果海藻酸钠寡糖能促进小鼠的生长性能,提高小鼠的胸腺和脾脏指数。其中给小鼠灌注高浓度的海藻酸钠寡糖15d后,与对照组相比,小鼠的特定生长率和增重率分别提高了37.0%和48.5%(P0.01),小鼠胸腺和脾脏指数分别提高了18.8%和21.7%(P0.01)。海藻酸钠寡糖还能增加小鼠的抗氧化活性,与对照组相比,灌注高浓度海藻酸钠寡糖组小鼠的SOD和GSH-Px活性分别提高了92.6%和35.9%(P0.01)。结论海藻酸钠寡糖能促进小鼠的生长性能,增强小鼠的免疫和抗氧化功能。     

Migration of bone marrow cells to the thymus in mice after a single sublethal-dose irradiation

In sublethally irradiated mice, thymus repopulation is due first to the proliferation of surviving thymocytes followed by the multiplication of bone marrow derived prothymocytes. The migration of bone marrow cells to the thymus after a single sublethal whole-body X irradiation was studied by using fluorescein isothiocyanate as a cell marker. Irradiation increases the permissiveness of the thymus to the immigration of bone marrow cells. Furthermore, the post-Rx regenerating bone marrow cells exhibit migration capacities greater than the normal ones. The radiation induced changes in the bone marrow thymus interaction might play an important role in thymus regeneration after sublethal irradiation.     

Cell transfer studies in cyclophosphamide-induced tolerance

Thymectomized, irradiated adult CBA mice were restored with various combinations of bone marrow and thymus cells from nontolerant animals and from animals made tolerant to sheep erythrocytes or to hemocyanin with the drug cyclophosphamide. Mice reconstituted with tolerant marrow and thymus responded as well as those that received nontolerant cells. Thus it is concluded that the tolerant state of the transferred marrow and thymus cells is not a significant factor in the tolerant state of the recipient, and that antigenic diversity is restored in the interaction and proliferation of bone marrow and thymus cells that follow transfer.Thymectomized irradiated mice restored with thymocytes, in contrast to unoperated animals, require multiple antigen injections to demonstrate comparable immune response, but develop tolerance normally when treated with cyclophosphamide and antigen. Reconstitution with tolerant marrow and thymus cells resembles the recovery of immune responsiveness seen after lethal irradiation of tolerant mice; in both instances a complete breakdown of immunological tolerance is observed.     

Use of flt3 ligand to evaluate residual hematopoiesis after heterogeneous irradiation in mice

We evaluated the possibility of using plasma Flt3 ligand (FL) concentration as a biological indicator of bone marrow function after heterogeneous irradiation. Mice were irradiated with 4, 7.5 or 11 Gy with 25, 50, 75 or 100% of the bone marrow in the field of irradiation. This model of irradiation resulted in graded and controlled damage to the bone marrow. Mice exhibited a pancytopenia correlated with both the radiation dose and the percentage of bone marrow irradiated. The FL concentration in the blood increased with the severity of bone marrow aplasia. Nonlinear regression analysis showed that the FL concentration was strongly correlated with the total number of residual colony-forming cells 3 days after irradiation, allowing a precise estimate of residual hematopoiesis. Moreover, the FL concentration on day 3 postirradiation was correlated with the duration and severity of subsequent pancytopenia, suggesting that variations in FL concentrations might be used as a predictive indicator of bone marrow aplasia, especially by the use of linear regression equations describing these correlations. Our results provide a rationale for the use of FL concentration as a biological indicator of residual hematopoiesis after heterogeneous irradiation.     

Effect of continuous, whole-body gamma irradiation upon canine lymphohematopoietic (CFU-GM, CFU-L) progenitors and a possible hematopoietic regulatory population

Clonogenic assays for granulocytes-macrophages (CFU-GM) in bone marrow and for T lymphocytes (CFU-L) in peripheral blood were performed on dogs continuously exposed to 60Co irradiation (0.02, 0.04, or 0.11 Gy/day). When decreased numbers of CFU-GM were observed they correlated well with the clinical status of the dogs but were not generally associated with increasing cumulative doses of absorbed irradiation. In clinically normal, irradiated animals, decreased CFU-GM values and myeloid-erythroid ratios were observed, suggesting that chronic irradiation may affect the granulocytic series well before decreased peripheral blood values are seen. In hypocellular dogs the number of CFU-GM were significantly decreased compared to values obtained from control or clinically normal irradiated dogs, while virtually no CFU-GM were observed in the leukemic dogs. Only the CFU-GM values of the hypocellular group showed an association, e.g., a suggestion of an abortive regenerative effort, with increasing absorbed dose. Proliferative capacity of T lymphocytes (CFU-L) was not affected by either increasing absorbed irradiation or the presence of leukemia. D0 values were determined on marrow fibroblastic cells to ascertain whether a radioresistant subpopulation of stromal elements would result from continuous in vivo irradiation. No correlation was found between absorbed dose and increased D0 values. However, seven of eight dogs which developed acute nonlymphocytic leukemia displayed marrow fibroblastic cells with elevated D0 values. These radioresistant marrow fibroblastic cells were assayed for their ability to support normal granulopoiesis and found to be not significantly different from control fibroblasts.     

Full reconstitution of the immune deficiency in scid mice with normal stem cells requires low-dose irradiation of the recipients

Mice homozygous for an autosomal recessive mutation for the scid gene exhibit a defect that specifically impairs lymphoid differentiation but not myelopoiesis. Such mice can be cured of their lymphoid deficiency by grafts with normal bone marrow, although full reconstitution of lymphoid function is seldom obtained. Long-term bone marrow cultures (LTBMC) are devoid of all mature B and pre-B cells but contain lymphoid stem cells. We therefore reconstituted scid mice with LTBMC cells to study the kinetics of B lymphocyte reconstitution in normal and irradiated (4 Gy) scid recipients and in irradiated (9.5 Gy) co-isogenic C.B-17 mice. Detectable colony-forming B cells rapidly increased in the spleen and bone marrow of irradiated C.B-17 and irradiated scid recipients, reaching normal levels between 4 and 6 wk post-grafting. Unirradiated scid recipients showed limited reconstitution in spleen and very poor reconstitution in bone marrow. Unirradiated scid recipients also had relatively few surface Ig+ cells in spleen or bone marrow, whereas both groups of irradiated recipients had normal numbers between 4 and 6 wk post-reconstitution. Normal levels of cytotoxic T cell activity by 8 wk after reconstitution were observed only in the irradiated C.B-17 and irradiated scid recipients. Analysis of mice reconstituted with cells from LTBMC indicates that these cultures contain lymphoid stem cells with significant proliferative and self-renewal potential, and that full reconstitution of lymphoid function requires prior irradiation of the scid recipient.     

Lipid metabolism in rat tissues during chronic gamma-irradiation and action of ubiquinone Q-9]

Chronic gamma-irradiation of rats with the daily dose of 0.129 Gy activates the synthesis of various classes of lipids in the thymus, spleen and bone marrow cells and induces lipid accumulation in these tissues. Feeding of rats with the antioxidant, ubiquinone Q-9, under conditions of chronic irradiation causes a considerable normalization of lipogenesis and levels of the lipid concentration in the tissues of animals irradiated with the dose of 20 Gy.     

CFU-S and haematopoietic microenvironment in mice after fractionated irradiation. A study on spleen colonies.

The paper is aimed at evaluating the quantity and quality of the haematopoietic stem cells, CFU-S, in the bone marrow and the functional effectiveness of the haematopoietic microenvironment of the spleen in two time intervals after repeated exposure of mice to doses of 0.5 Gy gamma-rays once a week (total doses of 12 and 24 Gy). After irradiation, bone marrow was cross-transplanted between fractionatedly irradiated and control mice. The parameter evaluated were numbers of spleen colonies classified into size categories. The data obtained provide evidence for a significant damage to the CFU-S, concerning both their number and proliferation ability, after both total doses used. The functional effectiveness of the haematopoietic microenvironment of the spleen was impaired only in bone marrow recipients receiving a transplant after having been exposed to a total dose of 24 Gy; this dose combined with subsequent pre-transplantation irradiation resulted in a marked suppression of cell production within the spleen colonies formed from a normal bone marrow on the spleens of fractionatedly irradiated mice.