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991.
Altered neutrophil apoptosis activity is reversed by melatonin in liver ischemia-reperfusion 总被引:2,自引:0,他引:2
Delayed neutrophil apoptosis has been implicated as the mechanism of the systemic inflammatory response. Herein, we examined the effect of melatonin on the neutrophil apoptosis in ischemia and reperfusion of the human liver. We studied seven patients receiving elective hepatectomy for liver tumor and ten patients receiving laparoscopic cholecystectomy for gallstones. Ten milli liters of blood was drawn isolation and incubation of the human neutrophils. Neutrophil apoptosis activity and CD18 expression and respiratory burst activity were assessed flow cytometrically. Another group of neutrophils included those from the patients receiving hepatectomy and isolated and incubated with melatonin. Neutrophil apoptosis is delayed from patients after hepatectomy or laparoscopic cholecystectomy when compared with that of the preoperative state. The decrease in the apoptosis activity is more severe in patients receiving hepatectomy as compared with those receiving laparoscopic cholecystectomy. Neutrophils from patients receiving hepatectomy or laparoscopic cholecystectomy are functionally activated. Melatonin can reverse the delayed process and enhance the apoptosis activity in neutrophils from patients receiving hepatectomy. This study demonstrates that melatonin enhances neutrophil apoptosis in patients receiving hepatectomy involving ischemia and reperfusion of the human liver. 相似文献
992.
Tokuhira M Watanabe R Iizuka A Sekiguchi Y Nemoto T Hanzawa K Takamatsu I Maruyama T Tamaru J Itoyama S Suzuki H Takeuchi T Mori S 《American journal of hematology》2007,82(2):162-167
Basophils play an important role in allergic inflammation and are pathologically related to hematological disturbances, such as iron deficiency anemia and myeloproliferative disorders; however, they are only rarely encountered in lymphoid malignancies. Here, we report the case of a 33-year-old man with a bulky mass of the small intestine, multiple paraaortic lymphoadenopathy, pleural effusion, and ascites, who was diagnosed as a case of de novo CD5+ diffuse large B cell lymphoma (DLBCL). This patient showed a marked elevation of the basophil count in the peripheral blood, which appeared to run in parallel with the tumor burden. High dose chemotherapy followed by autologous peripheral blood cell transplantation yielded complete remission, and the patient has remained disease free for 5 years. To the best of our knowledge, this is the first report of a case of de novo CD5+ DLBCL showing marked elevation of the PB basophil count. 相似文献
993.
Mitsuo Hori Shouichi Mitsuhashi Toshitaka Kobayashi Toshiro Nagasawa Naoyoshi Mori Masanao Miwa† Tsukasa Abe 《British journal of haematology》1994,88(2):419-420
Summary. CD30, Ki-1 antigen, an activated T-cell antigen, is a member of the nerve growth factor receptor family. This antigen is expressed on the lymphoma cells of some adult T-cell leukaemia/lymphoma (ATL/L) patients and some patients with Epstein-Barr virus infection. CD30-positive large cell cutaneous T-cell lymphomas occasionally integrate a defective HTLV-1 provirus. We describe here an HTLV-1 carrier who developed Ki-1 lymphoma with no evidence of monoclonal integration of the HTLV-1 proviral sequence. 相似文献
994.
目的观察用氯吡格雷(clopidogrel)治疗早期急性冠状动脉综合征(acute coronary syndrome,ACS)对病人血清可溶性CD40配体(soluble CD40ligand,sCD40L)的影响,了解该药对ACS斑块稳定性和免疫炎症抑制的作用。方法128例初次确诊为ACS病人分为常规治疗组62例和氯吡格雷治疗组66例,用酶联免疫吸附测定ACS病人治疗前后血清sCD40L水平的变化。结果氯吡格雷治疗组66例ACS病人治疗后血清sCD40L水平从(11.8±3.1)μg/L下降至(5.7±3.0)μg/L,与常规治疗组比较,差异有统计学意义(P<0.01)。结论使用氯吡格雷治疗早期ACS,可明显降低病人sCD40L水平。 相似文献
995.
Paczkowska E Larysz B Rzeuski R Karbicka A Jałowiński R Kornacewicz-Jach Z Ratajczak MZ Machaliński B 《European journal of haematology》2005,75(6):461-467
The hematopoietic and non-hematopoietic stem/progenitor cells harvested directly from the bone marrow (BM) or G-CSF mobilized peripheral blood were demonstrated to play an important role in regeneration of damaged organs (1, 2). Here, we asked if the stroke- or acute heart infarct-related stress triggers mobilization of stem/progenitor-enriched CD34(+)cells from the BM into the peripheral blood, which subsequently could contribute to regeneration of damaged tissues. To address this question the peripheral blood samples were harvested from patients with ischemic stroke during the first 24 h of manifestation of symptoms and on the second and sixth day afterwards or during the first 24 h of acute cardiac pain as well as on the second and sixth day of infarct. We measured in these patients (i) percentage of circulating hematopoietic stem/progenitor-enriched CD34(+) cells in peripheral blood by employing fluorescence activated cell sorter (FACS) and (ii) number of hematopoietic progenitor cells for the granulocyte-monocytic colony-forming unit (CFU-GM) and erythoid burst-forming unit (BFU-E) lineages circulating in peripheral blood. We concluded that stress related to ischemic stroke or acute myocardial infarction triggers the mobilization of hematopoietic stem/progenitor-enriched CD34(+) cells from the BM into peripheral blood. These circulating stem/progenitor-enriched CD34(+) cells may contribute to the regeneration of ischemic tissues, however, this possibility requires further studies. 相似文献
996.
Bolognesi A Polito L Tazzari PL Lemoli RM Lubelli C Fogli M Boon L de Boer M Stirpe F 《British journal of haematology》2000,110(2):351-361
Immunotoxins specific for the CD80 and CD86 antigens were prepared by linking three type 1 ribosome-inactivating proteins (RIPs), namely bouganin, gelonin and saporin-S6, to the monoclonal antibodies M24 (anti-CD80) and 1G10 (anti-CD86). These immunotoxins showed a specific cytotoxicity for the CD80/CD86-expressing cell lines Raji and L428. The immunotoxins inhibited protein synthesis by target cells with IC50s (concentration causing 50% inhibition) ranging from 0.25 to 192 pmol/l as RIPs. The anti-CD80 immunotoxins appeared 1-2 log more toxic for target cells than the anti-CD86 ones. Immunotoxins containing saporin and bouganin induced apoptosis of target cells. The toxicity for bone marrow haemopoietic progenitors of these conjugates was also evaluated. Bouganin and related immunotoxins at concentrations up to 100 nmol/l did not significantly affect the recovery of committed progenitors or of more primitive cells. The saporin-containing immunotoxins at concentrations >/= 1 nmol/l showed some toxicity on colony-forming unit cells (CFU-C). The expression of the CD80 and CD86 molecules is prevalently restricted to antigen-presenting cells and is also strong on Hodgkin and Reed-Sternberg cells in Hodgkin's disease. Present results suggest that immunotoxins targeting type 1 ribosome-inactivating proteins to these antigens could be considered and further studied for the therapy of Hodgkin's disease or other CD80/CD86-expressing tumours. 相似文献
997.
血凝素样氧化型低密度脂蛋白受体1在人脐静脉内皮细胞表达CD40中的作用 总被引:2,自引:0,他引:2
目的研究氧化低密度脂蛋白对人脐静脉内皮细胞表达CD40中血凝素样氧化型低密度脂蛋白受体1的作用。方法在氧化低密度脂蛋白作用人脐静脉内皮细胞前预先用血凝素样氧化型低密度脂蛋白受体1阻断剂角叉(菜)胶(κ-carrageenan)和多聚肌苷酸(PIA)作用1h,应用亲合组织化学技术检测血凝素样氧化型低密度脂蛋白受体1的表达,流式细胞技术检测细胞表面CD40的表达。结果预先加入血凝素样氧化型低密度脂蛋白受体1阻断剂PIA和角叉(菜)胶的CD40的表达低于氧化低密度脂蛋白组(P<0.05)。结论在人脐静脉内皮细胞的炎症反应中,氧化低密度脂蛋白通过血凝素样氧化型低密度脂蛋白受体1途径激活了CD40的表达。 相似文献
998.
OBJECTIVES: HIV-infected patients responding to combination antiretroviral therapy (ART) after experiencing severe immunodeficiency may exhibit persistent immune defects and occasionally experience opportunistic infections (OIs) despite increased CD4 T-cell counts. The investigation of immune defects in such patients was examined in this study. METHODS: CD4 effector memory T-cell (T(em)-cell) function [assessed by blood cytomegalovirus (CMV) interferon-gamma (IFN-gamma) enzyme-linked immunosorbent spot-forming cell assay (ELISPOT) counts] and B-cell dysregulation [assessed by serum immunoglobulin A (IgA) and IgE levels] were examined in 27 patients with increased CD4 T-cell counts after receiving ART for over 2 years. Two of these patients and one other had developed OIs on ART and are described in detail. RESULTS: Serum levels of IgA and IgE were higher than reference intervals (P<0.001) and CMV IFN-gamma ELISPOT counts were lower than those in non-HIV-infected controls (P<0.001) in the HIV-infected patients. Low CMV IFN-gamma ELISPOT counts were associated with high IgA levels (r=-0.5, P=0.01, Spearman's correlation test) and segregated with high IgE levels (P=0.06, Fisher's test). CMV IFN-gamma ELISPOT counts and serum IgA and IgE levels did not change significantly over a median time of 35 (range 8-60) months after the first measurement, whereas CD4 T-cell counts increased. All three patients who experienced OIs had repeatedly low CMV IFN-gamma ELISPOT counts and increased serum levels of IgA and/or IgE. CONCLUSION: Low CD4 T(em)-cell function and B-cell dysregulation are immune defects that may persist independently of changes in the CD4 T-cell count in HIV-1-infected patients responding to ART and are associated with an increased risk of developing an OI. 相似文献
999.
Sjöberg J Andersson M Garcia C Palucka KA Björkholm M Porwit-MacDonald A Pisa P 《British journal of haematology》2002,116(4):765-773
We investigated whether the described immune evasion of Epstein-Barr virus (EBV)-infected malignant Hodgkin and Reed-Sternberg (HRS) cells in Hodgkin's disease (HD) is paralleled by a disturbed expression of the signal transduction molecule zeta associated with CD3 and CD16 in tumour-associated T lymphocytes (TAL). Flow cytometric analysis revealed a significantly lower zeta expression in CD3+/4+, CD3+/8+ and CD16+ patient peripheral blood lymphocytes (PBL; n = 10) compared with normal donor PBLs (n = 11). When patient PBLs were compared with the corresponding TAL, the latter showed a significantly higher (CD3+/4+) or equal (CD3+/8+) zeta expression. The EBV status of the tumours did not correlate with zeta expression in the TAL. Immunohistochemical staining revealed zeta-positive lymphocytes among the adjacent bystander cells of the HRS cells in all analysed tumours (n = 8), irrespective of tumour EBV status. In conclusion, these results do not support downregulation of zeta in TAL as a critical mechanism contributing specifically to the immune escape of EBV+ HRS cells. 相似文献
1000.
Ting SS Tangye SG Wood J Ffrench RA Ziegler JB 《British journal of haematology》2001,112(4):1004-1011
X-linked severe combined immunodeficiency (XSCID) is a lethal disease resulting in death in infancy. In many instances, haploidentical bone marrow transplantation (BMT) offers reconstitution of T-cell immunity alone, with residual hypogammaglobulinaemia. The exact nature of B-cell dysfunction in these patients is unclear, although differentiation arrest of the B cells is a potential explanation. To ascertain the differentiation status of peripheral blood B lymphocytes from XSCID patients after BMT, the surface expression of CD19, CD10, CD34, CD5, serum immunoglogulin (sIg)M, sIgD, sIgG and CD27 on these B cells was investigated using three-colour flow cytometry. CD27 is a marker of memory B cells. Populations of CD19+IgM-D- B cells, CD19+IgM-only, CD19+IgG+CD27+ and CD19+IgM+ CD27+ B cells were found to be diminished in the XSCID patients after BMT with persistent hypogammaglobulinaemia, compared with both post-BMT patients with B-cell function and age-matched normal controls. This indicated the lack of CD19+IgM-D- B cells, which represent Ig isotype-switched B cells, as well as CD19+IgM-only and CD19+IgG+CD27+ or CD19+IgM+CD27+ memory B-cell populations. Interaction between CD27 and its ligand CD70 has been shown to induce IgG and IgM production by CD27+ B cells. Therefore, the lack of CD27/70 interaction is a probable explanation for the hypogammaglobulinaemia in these patients after BMT. 相似文献