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81.
Induction of cytotoxic T lymphocyte responses by cholera toxin-treated bone marrow-derived dendritic cells 总被引:4,自引:0,他引:4
Cholera toxin (CT), a powerful mucosal adjuvant, is a potent inducer of Th2-type responses via activation of co-stimulatory molecules for the induction of IgA antibody responses. Less appreciated is the ability of CT to induce and regulate cytotoxic T lymphocyte (CTL) responses. In order to help for clarifying mechanisms underlying the CTL-inducing ability of CT, we have examined the effects of CT on dendritic cells (DCs) that could lead to the induction of cytotoxic CD8(+) T cells. When bone marrow-derived DCs (BM-DCs) were cultured with CT in vitro, B7-1 but not B7-2 molecules were significantly enhanced and allogenic CTL responses were induced. Also, increased numbers of IFN-gamma-secreting CD8(+) T cells were elicited when CT-treated BM-DCs were co-cultured with allogenic CD8(+) CTLs. Antibody blockade of B7-1 on CT-treated BM-DCs suppressed allogenic CTL responses, further indicating the importance of CT-induced B7-1 molecules on DCs for the acquisition of cytolytic function by CTL precursors. CD40 signaling was proven not necessary for the CT-induced CTL response since CT-treated CD40(-/-) BM-DCs developed CTL responses equivalent to those detected in CT-treated BM-DCs derived from normal mice. Our results suggest that CT-treated DCs are effective inducers of CD8(+) CTL, and this induction is mediated through CT's ability to enhance B7-1 expression on DCs. 相似文献
82.
Isolation and characterization of anticomplementary beta-glucans from the shoots of bamboo Phyllostachys edulis 总被引:1,自引:0,他引:1
Bamboo, Phyllostachys edulis produces well known edible shoots in Asia. Immunostimulating anticomplementary (complement activating) substances have been recognized as a characteristic biological response modifier (BRM). In the present study, we isolated and characterized three anticomplementary beta-glucans (BS-BGA, BS-BGB, and BS-BGC) from bamboo shoots. Hot-water extraction, DEAE-Toyopearl 650M-column chromatography, amylase digestion and concanavalin A adsorption, and Sephacryl S-100 HR column chromatography were applied to isolate the beta-glucans. The average molecular masses of the beta-glucans were estimated to be from 14,500 to 85,300 Da by HPSEC-MALLS-RI. All three beta-glucans (0.1-1.0 mg/mL) activated the complement system via the alternative pathway, and could cleave human complement C3 under Ca 2+-free gelatin veronal buffered saline. Among them, the largest molecule, BS-BGA was the most potent complement activator. Methylation analysis and NMR spectroscopy were used to achieve their structural characterization. They are all water-soluble and composed mainly of backbone structures of beta-(1-->3)-glucan with beta-(1-->4)-linked side chains varying in degree of branching. BS-BGA consisted of a higher proportion of 3-linked glucopyranosyl residues and a lower degree of branching than BS-BGB and BS-BGC. In particular, BS-BGA contained a small amount of O-acetyl groups at C-6 of the 3-linked glucopyranosyl residues. These data demonstrate that the structural characteristics including molecular size, degree of branching, and O-acetyl substitution are involved, at least in part, in their different anticomplementary activities. 相似文献
83.
Feng G Reale V Chatwin H Kennedy K Venard R Ericsson C Yu K Evans PD Hall LM 《The European journal of neuroscience》2003,18(2):227-238
A cDNA clone encoding a seven-transmembrane domain, G-protein-coupled receptor (NPFR76F, also called GPCR60), has been isolated from Drosophila melanogaster. Deletion mapping showed that the gene encoding this receptor is located on the left arm of the third chromosome at position 76F. Northern blotting and whole mount in situ hybridization have shown that this receptor is expressed in a limited number of neurons in the central and peripheral nervous systems of embryos and adults. Analysis of the deduced amino acid sequence suggests that this receptor is related to vertebrate neuropeptide Y receptors. This Drosophila receptor shows 62-66% similarity and 32-34% identity to type 2 neuropeptide Y receptors cloned from a variety of vertebrate sources. Coexpression in Xenopus oocytes of NPFR76F with the promiscuous G-protein Galpha16 showed that this receptor is activated by the vertebrate neuropeptide Y family to produce inward currents due to the activation of an endogenous oocyte calcium-dependent chloride current. Maximum receptor activation was achieved with short, putative Drosophila neuropeptide F peptides (Drm-sNPF-1, 2 and 2s). Neuropeptide F-like peptides in Drosophila have been implicated in a signalling system that modulates food response and social behaviour. The identification of this neuropeptide F-like receptor and its endogenous ligand by reverse pharmacology will facilitate genetic and behavioural studies of neuropeptide functions in Drosophila. 相似文献
84.
4分子治疗分析肿瘤细胞中的分子遗传性变异及后天变异的方法正在快速成熟起来。这些方法通常涉及基因组学、转录特征性识别及蛋白质组学,有利于更深入地了解ALL的发病机理,使用于临床评估的靶向治疗全面发展。最终,这些层出不穷的新技术将营造出一个全新的个性化分子医学时代,创造出效果更好而毒性更低的治疗方案。尽管治疗方案均显示了药物介入控制细胞周期进程、基因转录、细胞运动、凋亡及细胞代谢信号通路的可行性(图1),但针对ALL的分子治疗情况(表1)仍差强人意。我们将从众多正处于临床前期或早期临床研究的分子治疗方案中,选择出那… 相似文献
85.
利用目前的治疗手段,80%的急性淋巴细胞白血病(acute lymphoblastic leukem ia,ALL)患儿均能得到治愈,尚有部分患者需接受强化治疗,但治疗的副作用也带来了急性或远期的严重并发症。此外,成人ALL病人的生存率依然低于40%。因此,本病需要既可以提高治愈率又能改善生活质量的新治疗方案。本文讨论了新出现的可能会改善ALL病人预后的治疗方法,包括现有常规化疗药物的新剂型、新的抗代谢药和核苷衍生物、白血病相关抗原的单克隆抗体,针对白血病细胞的基因异常及相关信号通路的分子治疗。1常规化疗药物的新剂型化疗药物的脂质体剂型是将药物… 相似文献
86.
N. MATSANIOTIS F. TZORTZATOU-STATHOPOULOU TH. THOMAIDIS Z. KARAKATSANI-KERASIOT CH. THEODORIDIS C. DACOU-VOUTETAKIS 《Acta paediatrica (Oslo, Norway : 1992)》1981,70(6):949-950
Abstract. Matsaniotis, N., Tzortzatou-Stathopoulou, F., Thomaidis, Th., Karakatsani-Kerasioti, Z., Theodoridis, Ch. and Dacou-Voutetakis, C. (First Department of Paediatrics of Athens University, "Aghia Sophia" Children's Hospital, Athens, Greece). Diabetes mellitus and Addison's disease in an adolescent female. Acta Paediatr Scand, 70: 949, 1981.-This short report describes a 16-year-old female who presented with Addison's disease 6 years after diabetes mellitus had been diagnosed. The possibility of both conditions being present should be borne in mind whenever an unexplained reduction of insulin requirements is noted, especially if this is accompanied by cutaneous pigmentation. The metabolic interrelationships of the two conditions are briefly discussed. 相似文献
87.
S. F. Varavi M.D. D.C.H. J. R. Kamat MD. D.CH M. K. Joshi M.D. D.C.H. Dr. P. W. Kandoth M.D. D.C.H. 《Indian journal of pediatrics》1982,49(5):665-669
Immunoglobulins were estimated in the cerebrospinal fluid from 70 cases of nervous system diseases. Thirty childern with evidence of C.N.S. irritation without infection served as controls. The immunoglobulins were higher in cases with C.N. S infections. Within this group meningeal involvement (tubercular and pyogenic) resulted in a significant rise in IgG compared to viral encephalitis. The proportion of immunoglobulin in the CSF protein can be helpful in distinguishing TBM from PM. 相似文献
88.
Julien Labrie Yolanda van der Graaf Eric Buskens Stella ESM Tiersma Huub CH van der Vaart 《BMC women's health》2009,9(1):24
Background
Stress urinary incontinence is a common condition affecting approximately 20% of adult women causing substantial individual (quality of life) and economic (119 million Euro/year spent on incontinence pads in the Netherlands) burden. Pelvic floor muscle training (PFMT) is regarded as first line treatment, but only 15-25% of women will be completely cured. Approximately 65% will report that their condition improved, but long term adherence to treatment is problematic. In addition, at longer term (2-15 years) follow-up 30-50% of patients will end up having surgery. From 1996 a minimal invasive surgical procedure, the Tension-free Vaginal Tape (TVT) has rapidly become the gold standard in surgical treatment of stress urinary incontinence. With TVT 65-95% of women are cured. However, approximately 3-6% of women will develop symptoms of an overactive bladder, resulting in reduced quality of life. Because of its efficacy the TVT appears to be preferable over PFMT but both treatments and their costs have not been compared head-to-head in a randomised clinical trial. 相似文献89.
Stenosis of the vena cava: preliminary assessment of treatment with expandable metallic stents 总被引:11,自引:0,他引:11
Charnsangavej C; Carrasco CH; Wallace S; Wright KC; Ogawa K; Richli W; Gianturco C 《Radiology》1986,161(2):295-298
To test the ability of Gianturco expandable metallic stents to dilate and maintain patency in stenotic venae cavae, stenosis of the inferior vena cava was created in seven mongrel dogs by the percutaneous injection of absolute ethanol into the paravascular retroperitoneal space. Gianturco stents, placed across the stenotic segment, resulted in successful dilatation with improved hemodynamics in four dogs. The stents failed to dilate an occluded vena cava in one dog; in the remaining dogs, stent placement was complicated by early migration and occlusion. Gianturco stents were placed in two patients, one with superior vena cava syndrome and one with retroperitoneal fibrosis that obstructed the inferior vena cava, and resulted in immediate relief of presenting symptoms. These results should be viewed cautiously, but further investigation into the clinical use of the stents is indicated, especially for patients for whom other treatments are difficult. 相似文献
90.
Kweon Young Kim Soo Jin Choi Hyuk Jin Jang Dong Chuan Zuo Pawan Kumar Shahi Shankar Prasad Parajuli Cheol Ho Yeum Pyung Jin Yoon Seok Choi Jae Yeoul Jun 《The Korean journal of physiology & pharmacology》2008,12(3):111-115
The effects of (-)-epigallocatechin gallate (EGCG) on pacemaker activities of cultured interstitial cells of Cajal (ICC) from murine small intestine were investigated using whole-cell patch-clamp technique at 30℃ and Ca2+ image analysis. ICC generated spontaneous pacemaker currents at a holding potential of -70 mV. The treatment of ICC with EGCG resulted in a dose-dependent decrease in the frequency and amplitude of pacemaker currents. SQ-22536, an adenylate cyclase inhibitor, and ODQ, a guanylate cyclase inhibitor, did not inhibit the effects of EGCG. EGCG-induced effects on pacemaker currents were not inhibited by glibenclamide, an ATP-sensitive K+ channel blocker and TEA, a Ca2+-activated K+ channel blocker. Also, we found that EGCG inhibited the spontaneous [Ca2+]i oscillations in cultured ICC. In conclusion, EGCG inhibited the pacemaker activity of ICC and reduced [Ca2+]i oscillations by cAMP-, cGMP-, ATP-sensitive K+ channel-independent manner. 相似文献