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排序方式: 共有782条查询结果,搜索用时 31 毫秒
31.
Two pathways of exocytosis of cytoplasmic granule contents and target cell killing by cytokine-induced CD3+ CD56+ killer cells 总被引:40,自引:0,他引:40
Cytokine-induced killer (CIK) cells are non-major histocompatibility complex-restricted cytotoxic cells generated by incubation of peripheral blood lymphocytes with anti-CD3 monoclonal antibody (MoAb), interleukin-2 (IL-2), IL-1, and interferon-gamma. Cells with the greatest effector function in CIK cultures coexpress CD3 and CD56 surface molecules. CIK cell cytotoxicity can be blocked by MoAbs directed against the cell surface protein leukocyte function associated antigen-1 but not by anti-CD3 MoAbs. CIK cells undergo release of cytoplasmic cytotoxic granule contents to the extracellular space upon stimulation with anti-CD3 MoAbs or susceptible target cells. Maximal granule release was observed from the CD3+ CD56+ subset of effector cells. The cytoplasmic granule contents are lytic to target cells. Treatment of the effector cells with a cell-permeable analog of cyclic adenosine monophosphate (cAMP) inhibited anti-CD3 MoAb and target cell- induced degranulation and cytotoxicity of CIK cells. The immunosuppressive drugs cyclosporin (CsA) and FK506 inhibited anti-CD3- mediated degranulation, but did not affect cytotoxicity of CIK cells against tumor target cells. In addition, degranulation induced by target cells was unaffected by CsA and FK506. Our results indicate that two mechanisms of cytoplasmic granule release are operative in the CD3+ CD56+ killer cells; however, cytotoxicity proceeds through a cAMP- sensitive, CsA- and FK506-insensitive pathway triggered by yet-to-be- identified target cell surface molecules. 相似文献
32.
6q deletions define distinct clinico-pathologic subsets of non- Hodgkin's lymphoma 总被引:11,自引:1,他引:11
Offit K; Parsa NZ; Gaidano G; Filippa DA; Louie D; Pan D; Jhanwar SC; Dalla- Favera R; Chaganti RS 《Blood》1993,82(7):2157-2162
Commonly observed in lymphoid neoplasms, deletions of 6q have been correlated with histologic and clinical subsets of non-Hodgkin's lymphoma (NHL). Our recent analysis of loss of heterozygosity of 6q loci in NHL showed two regions of minimal molecular deletion (RMD), an RMD1 at 6q25-27 and an RMD2 at 6q21-23. To establish correlations between these RMDs and regions of minimal cytogenetic deletions (RCDs) on 6q, and to define associations between RCDs and clinico-pathologic features, we have analyzed chromosome 6 abnormalities in 459 consecutively ascertained, karyotypically abnormal cases of NHL. Among these, 126 (27.5%) cases had structural abnormalities of chromosome 6, of which 94 were deletions. Analysis of these deletions identified three RCDs. An RCD1 encompassing 6q25-27 was seen in 45 intermediate- grade NHL. An RCD2 at 6q21 was observed in 11 high-grade NHL, 9 of which were of the immunoblastic subtype. An RCD3 at 6q23 was noted in 18 low-grade NHL lacking a t(14;18) translocation. Of these 18 cases, 12 were small lymphocytic NHL and, in 2 of these, del(6q) was the sole karyotypic abnormality. In 20 cases of low-grade NHL with t(14;18), the deletions spanned both RCD1 and RCD3. These data suggested the presence of at least 3 tumor suppressor genes on 6q within RCD1, RCD2, and RCD3; they also showed associations between RCDs in 6q and subsets of NHL, including a specific association between a group of well-differentiated lymphoid neoplasms and RCD3. The apparent heterogeneity of breakpoints when all NHLs are considered together explains the inability of previous studies to reliably establish correlations between recurring 6q deletions and histologic and clinical features of NHL. 相似文献
33.
Hannah X Chu Hyun Ah Kim Seyoung Lee Jeffrey P Moore Christopher T Chan Antony Vinh Mathias Gelderblom Thiruma V Arumugam Brad RS Broughton Grant R Drummond Christopher G Sobey 《Journal of cerebral blood flow and metabolism》2014,34(3):450-459
We tested whether significant leukocyte infiltration occurs in a mouse model of permanent cerebral ischemia. C57BL6/J male mice underwent either permanent (3 or 24 hours) or transient (1 or 2 hours+22- to 23-hour reperfusion) middle cerebral artery occlusion (MCAO). Using flow cytometry, we observed ∼15,000 leukocytes (CD45+high cells) in the ischemic hemisphere as early as 3 hours after permanent MCAO (pMCAO), comprising ∼40% lymphoid cells and ∼60% myeloid cells. Neutrophils were the predominant cell type entering the brain, and were increased to ∼5,000 as early as 3 hours after pMCAO. Several cell types (monocytes, macrophages, B lymphocytes, CD8+ T lymphocytes, and natural killer cells) were also increased at 3 hours to levels sustained for 24 hours, whereas others (CD4+ T cells, natural killer T cells, and dendritic cells) were unchanged at 3 hours, but were increased by 24 hours after pMCAO. Immunohistochemical analysis revealed that leukocytes typically had entered and widely dispersed throughout the parenchyma of the infarct within 3 hours. Moreover, compared with pMCAO, there were ∼50% fewer infiltrating leukocytes at 24 hours after transient MCAO (tMCAO), independent of infarct size. Microglial cell numbers were bilaterally increased in both models. These findings indicate that a profound infiltration of inflammatory cells occurs in the brain early after focal ischemia, especially without reperfusion. 相似文献
34.
Prevalence of Candida spp., xerostomia,and hyposalivation in oral lichen planus – A controlled study
Objective
To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non‐OLP group), and subjects without oral mucosal lesions (control group).Material and methods
Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non‐OLP lesions (28 patients), and healthy subjects (32 subjects).Results
There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non‐OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp.Conclusions
Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme. 相似文献35.
KH Neppelenbroek RS Seó VM Urban S Silva LN Dovigo JH Jorge NH Campanha 《Oral diseases》2014,20(4):329-344
In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species. 相似文献
36.
37.
Marcelo Kirschbaum Vitor Emer Egypto Rosa Brunna Pileggi Azevedo Sampaio Gabriela Thevenard Ndia Romanelli Quintanilha Joo Ricardo Cordeiro Fernandes Antonio de Santis Tarso Duenhas Accorsi Roney Orismar Sampaio Flavio Tarasoutchi 《Arquivos brasileiros de cardiologia》2022,118(3):588
BackgroundThe bicuspid aortic valve (BAV) affects 0.5 to 2% of the population and is associated with valve and aortic alterations. There is a lack of studies on the profile of these patients in the Brazilian population.ObjectiveTo describe the profile of patients with BAV undergoing valve and/or aortic surgery in a tertiary cardiology center, in addition to the outcomes related to the intervention.MethodsRetrospective cohort including 195 patients (mean age 54±14 years, 73.8% male) diagnosed with BAV who underwent surgical approach (valvular and/or aorta) from 2014 to 2019. Clinical data, echocardiographic and tomographic studies were evaluated, as well as characteristics of the intervention and events in 30 days. A value of p<0.05 was considered statistically significant.ResultsWe found a high prevalence of aortic aneurysm (56.5%), with a mean diameter of 46.9±10.2 mm. Major aortic regurgitation was found in 25.1% and major aortic stenosis in 54.9%. Isolated aortic valve surgery was performed in 48.2%, isolated aortic surgery in 6.7% and combined surgery in 45.1%. The 30-day mortality was 8.2%. In the multivariate analysis, the predictors of the combined outcome at 30 days (death, atrial fibrillation and reoperation) were age (OR 1.044, 95% CI 1.009-1.081, p=0.014) and left ventricular mass index (OR 1.009, 95% CI 1.000-1.018, p=0.044).ConclusionPatients with BAV approached in our service have a higher incidence of aortopathy, with the additional need to evaluate the aorta with computed tomography or magnetic resonance imaging. 相似文献
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40.
目的:探索糖稳态调节细胞定向分化的基因改造方案思路.方法:①研究构建的解除干细胞分化抑制状态的信号传导与转录激活因子-3(STAT-3)基因载体,检测其介导目的基因感染ARIP等细胞基因表达;②研究构建的活化配体DL诱导N信号、在"旁侧抑制"过程中扮演重要角色的Kuzbanian(KUZ)基因载体在转基因小鼠表达后糖稳态调节细胞的分化.结果:在完成的STAT-3腺病毒基因载体生产了腺病毒,用带有目的基因的腺病毒对ARIP靶细胞进行感染,3 d后,荧光显微镜观察时,活细胞、固定液固定细胞均看到了构建基因中绿色荧光蛋白成功、高效的阳性表达报告.在完成的Kuzbanian(KUZ)基因载体构建、转基因、动物模型、小鼠品系鉴定后,用非放射性原位杂交实验对胰腺靶细胞的mRNA进行检测,获得了预期的阳性结果.结论:通过用某些分化抑制性基因的显性失活形式(DN)竞争性预先解除干细胞分化的抑制状态,然后再定向分化诱导使之朝向期望的目标细胞方向分化,可能是糖稳态细胞定向分化的可行途径之一. 相似文献