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51.
H. J. J. Kars Juha M. Hijmans Jan H. B. Geertzen Wiebren Zijlstra 《Journal of diabetes science and technology》2009,3(4):931-943
The objective of this review is to identify and review publications describing the impact of reduced somatosensation on balance. Based on knowledge of the association between specific somatosensory loss and deterioration of balance, conclusions can be made about role of somatosensation in standing balance.A systematic literature review is presented in which publications from the years 1993 through 2007 were searched in Medline and Embase. Medical Subject Headings (MESH) terms and free text words (related to balance, somatosensory loss, and lower limb) were used to perform the searches. Fifteen articles were selected for detailed review based on predetermined inclusion criteria, and three of the included articles described the effect of experimentally reduced somatosensation on balance in healthy subjects. Ten of the articles described balance in diabetic neuropathy (DN). The last two included articles described balance in Charcot-Marie-Tooth (CMT) disease type 1A (CMT1A) or type 2 (CMT2).The literature indicates that the tactile sensation is reduced in DN, CMT1A, and CMT2 and when the plantar surface of the feet was hypothermically anesthetized. Joint motion sensation seems to be impaired in patients with DN, and passive joint position sensation appears to be reduced in healthy subjects with anesthesia of ankle and foot from prolonged ischemia. This reduced somatosensation seems to have a negative effect on balance in patients with DN and CMT2; however, this appeared not to be the case in patients with CMT1A and in healthy subjects. 相似文献
52.
Jing‐Ping Zhang Limin Zheng Jiang‐Hai Wang Karl‐Eric Magnusson Xin Liu 《Phytotherapy research : PTR》2009,23(6):844-850
Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
53.
54.
Immune reactivity towards insulin, its amyloid and protein S100B in blood sera of Parkinson's disease patients 总被引:1,自引:0,他引:1
K. R. Wilhelm K. Yanamandra M. A. Gruden V. Zamotin M. Malisauskas V. Casaite A. Darinskas L. Forsgren L. A. Morozova-Roche 《European journal of neurology》2007,14(3):327-334
Peripheral immune responses can be sensitive indicators of disease pathology. We evaluated the autoimmune reactions to endocrine (insulin) and astrocytical (S100B) biomarkers in the blood sera of 26 Parkinson's disease (PD) patients compared with controls by using ELISA. We found a statistically significant increase of the autoimmune responses to both antigens in PD patients compared with controls with a mean increase of 70% and 50% in the autoimmune reactions towards insulin and S100B, respectively. Heterogeneity of the immune responses observed in patients may reflect the modulating effect of multiple variables associated with neurodegeneration and also changes in the basic mechanisms of individual autoimmune reactivity. We did not detect any pronounced immune reactions towards insulin amyloid fibrils and oligomers in PD patients, indicating that an amyloid-specific conformational epitope is not involved in immune recognition of this amyloid type, while sequential epitope of native insulin is hidden within the amyloid structures. Immune reactions towards S100B and insulin may reflect the neurodegenerative brain damaging processes and impaired insulin homeostasis occurring in PD. 相似文献
55.
Mary Locniskar PhD Kathleen M. Nauss PhD Paul M. Newberne DVM PhD 《Digestive diseases and sciences》1987,32(7):747-752
Twoin vitro models of immune surveillance were used to examine the immune status of the gut-associated lymphoid tissue, mesenteric lymph nodes, and spleen during the early stages of 1,2-dimethylhydrazine (DMN)-induced colon tumorigenesis. DMH-and vehicletreated Fischer rats were sacrificed at one of three time points; one week, two months, or five months after cessation of treatment. Colonic, lymph node, and splenic natural killer cell cytolytic activity toward YAC-1 tumor targets and T-cell response to autologous la-induced balstogenesis were measured at each time point. We found little change in natural killer cell activity or T-cell proliferation induced by autologous Ia gene products at these time periods.This investigation was supported in part by grant CA26917 from the National Cancer Institute, Department of Health and Human Services. 相似文献
56.
目的 研究甘肃棘豆生物碱部位对KM小鼠肝癌H22细胞抑制作用及其对KM小鼠免疫功能的影响。 方法 采用鼠源性肝癌细胞H22移植瘤法,将60只KM小鼠随机分为5组,其中高、中、低剂量组分别给予甘肃棘豆生物碱部位32、16、8 mg/kg体重灌胃,阴性对照组给予生理盐水(NS)20 mL/kg灌胃,5- 氟脲嘧啶(5-FU)组给予5-FU 15 mg/kg体重腹腔注射,每天1次,连续给药10天。检测平均瘤重和抑瘤率,计算脾指数、胸腺指数,MTT法测脾细胞增殖率。 结果 甘肃棘豆生物碱部位高、中、低剂量组对肝癌细胞H22实体移植瘤的抑制率分别为43%、29%、23%;各剂量组小鼠的脾指数和胸腺指数均明显高于阴性对照组,中、高剂量组明显高于5-FU 组(P<0.05);各剂量组在24、48、72 h的脾细胞增殖率也明显高于阴性对照组及5-FU 组(P<0.01)。 结论 甘肃棘豆生物碱部位对KM小鼠肝癌H22移植瘤有抑制作用,并能增强KM小鼠免疫功能。 相似文献
57.
Mathematical modelling of the spatio-temporal response of cytotoxic T-lymphocytes to a solid tumour.
Anastasios Matzavinos Mark A J Chaplain Vladimir A Kuznetsov 《Mathematical medicine and biology》2004,21(1):1-34
In this paper a mathematical model describing the growth of a solid tumour in the presence of an immune system response is presented. In particular, attention is focused upon the attack of tumour cells by so-called tumour-infiltrating cytotoxic lymphocytes (TICLs), in a small, multicellular tumour, without necrosis and at some stage prior to (tumour-induced) angiogenesis. At this stage the immune cells and the tumour cells are considered to be in a state of dynamic equilibrium--cancer dormancy--a phenomenon which has been observed in primary tumours, micrometastases and residual disease after ablation of the primary tumour. Nonetheless, the precise biochemical and cellular mechanisms by which TICLs control cancer dormancy are still poorly understood from a biological and immunological point of view. Therefore we focus on the analysis of the spatio-temporal dynamics of tumour cells, immune cells and chemokines in an immunogenic tumour. The lymphocytes are assumed to migrate into the growing solid tumour and interact with the tumour cells in such a way that lymphocyte-tumour cell complexes are formed. These complexes result in either the death of the tumour cells (the normal situation) or the inactivation (sometimes even the death) of the lymphocytes. The migration of the TICLs is determined by a combination of random motility and chemotaxis in response to the presence of chemokines. The resulting system of four nonlinear partial differential equations (TICLs, tumour cells, complexes and chemokines) is analysed and numerical simulations are presented. We consider two different tumour geometries--multi-layered cell growth and multi-cellular spheroid growth. The numerical simulations demonstrate the existence of cell distributions that are quasi-stationary in time and heterogeneous in space. A linear stability analysis of the underlying (spatially homogeneous) ordinary differential equation (ODE) kinetics coupled with a numerical investigation of the ODE system reveals the existence of a stable limit cycle. This is verified further when a subsequent bifurcation analysis is undertaken using a numerical continuation package. These results then explain the complex heterogeneous spatio-temporal dynamics observed in the partial differential equation (PDE) system. Our approach may lead to a deeper understanding of the phenomenon of cancer dormancy and may be helpful in the future development of more effective anti-cancer vaccines. 相似文献
58.
Tick-borne encephalitis (TBE) virus is an important human pathogenic flavivirus that is endemic in Europe and Asia. The disease can be effectively prevented by inactivated vaccines and vaccination breakthroughs (VBTs) are rare. We investigated the characteristics of antibody responses in such VBTs in comparison to those in unvaccinated TBE patients. In contrast to the unvaccinated controls, most of the VBTs displayed a delayed IgM antibody response and had high avidity and strongly neutralizing antibodies already in the first sample taken upon hospitalization. The antibody profile of these patients therefore had the characteristics of an anamnestic immune response. In the VBTs analyzed, immunological priming and memory were apparently not sufficient or fast enough to prevent the disease. 相似文献
59.
目的 探讨 IL - 4和 IL - 10在诱导异种骨移植免疫耐受中的作用。方法 反应细胞为 BAL B/c小鼠脾淋巴细胞 ,刺激细胞为新西兰白兔血淋巴细胞 ,刺激抗原为兔骨上清液。采用经典的混合淋巴细胞培养法及骨上清液与淋巴细胞混合培养法作为异种骨移植的体外实验模型。在各培养液中分别加入 IL - 4、IL - 10及两者联合应用 ,通过测定其 3H- Td R掺入率 ,观察不同细胞因子对刺激淋巴细胞增殖的影响。结果 无论在细胞刺激组还是骨上清液刺激组 ,IL- 4对淋巴细胞增殖均有显著抑制作用 (P<0 .0 0 1和 P<0 .0 5 ) ,IL- 10未表现出抑制作用 (P>0 .0 5 )。在两组 IL- 4和 IL - 10联合应用均产生比 IL - 4单独应用更为明显的细胞增殖抑制作用 (P<0 .0 0 1和 P<0 .0 5 )。结论 IL - 4对由细胞或骨上清液刺激产生的淋巴细胞增殖均有很好的抑制作用 ,IL- 10没有表现出抑制作用 ;IL- 4与 IL- 10联合应用有协同抑制作用。 相似文献
60.
目的 探讨门腔分流术后病人给予含丙氨酰 谷氨酰胺双肽 (Ala GLN)肠外营养 (PN)的安全性 ;观察其营养支持的效果 ,及对肠道通透性的影响。方法 16例病人随机分为两组。对照组(n =7)接受不含GLN的PN ;实验组 (n =9)接受含Ala GLN双肽的PN。两组自术后第 1天起给予等氮、等热量的PN共 7d ,于PN前后分别测定血清前白蛋白、氮平衡变化、血清GLN浓度、血氨、尿乳果糖 /甘露醇排泄率比值 (L/Mratio)、生化和临床指标的变化。结果 对照组术后血清GLN水平比术前显著降低 ,术后实验组GLN水平 (5 77± 4 2 ) μmol/L显著 (P =0 0 0 9)高于对照组术后水平 (499± 6 1)μmol/L ;两组术前的L/M比率均明显高于国人正常水平 ,术后对照组L/M水平 (0 0 95± 0 0 34)显著 (P=0 0 4 5 )高于实验组 (0 0 6 4± 0 0 2 3) ;两组累积氮平衡无显著性差异 ,但实验组第 5~ 7天期间氮平衡要明显优于对照组 ,实验组第 5天氮平衡 (- 15 3± 4 6 9)mg·kg-1·d-1显著 (P =0 0 4 3)好于对照组 (-92 7± 90 5 )mg·kg-1·d-1;对照组术后血清前白蛋白水平较术前显著下降 ,实验组术后血清前白蛋白水平 (0 2 6 9± 0 0 37)g/L显著 (P =0 0 0 1)高于对照组 (0 199± 0 0 2 7)g/L ;两组术后血氨水平相比无统计学意义 ;生 相似文献