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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.
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
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34.
Most congenital lateral cervical cysts, fistulae, and skin tags are considered to be from the branchial apparatus. This is a 13-year review of 58 patients (with 66 branchial lesions) who were operated on. There were eight simple cysts and six cysts with a fistula; 43 external fistulae with or without an internal opening, and nine skin tags. Eighty-seven percent (39/45) of patients with skin tags and external fistulae were less than 5 years of age at the time of operation. On the other hand, all eight patients with cysts but no fistula were greater than 9 years of age. Eight lesions were considered to be the first branchial remnants, and 44 lesions were suspected to be from the second branchial cleft. One external fistula with an internal communication to the pharynx at the level of thyrohyoid membrane was considered to be a third (or fourth) branchial remnant. The other branchial cyst with thyroid tissue in its wall was suggested to be a fourth branchial remnant. Pathology of the excised lesions showed columnar, squamous, or a mixed epithelium. Lymphoid aggregates were documented in 31 patients. Duration of hospital stay was short, except for four patients with first cleft defects who stayed more than five days. Three of the four recurrent cases were first branchial remnants, including one case with the first operation performed at another hospital. In view of these findings, first branchial remnants must be excised with extra care. 相似文献
35.
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36.
37.
38.
George A. Heckman Alyana Karim Shamji Raisa Ladha Jackie Stapleton Veronique Boscart Rebecca S. Boxer Lora Bruyn Martin Lauren Crutchlow Robert S. McKelvie 《The Canadian journal of cardiology》2018,34(7):871-880
Heart failure (HF) affects 20% of nursing home (NH) residents, causing high morbidity and mortality. The optimal approach to HF management in NHs remains elusive. We conducted a scoping review of published guidelines and HF management interventions in NHs. A search for English publications since 1990 was conducted using PubMed, EMBASE, CINAHL, and Scopus, for scientific statements, guidelines, recommendations, or intervention studies that addressed at least 1 principle of HF management. Of 2545 records retrieved, 19 articles were retained after screening, and 2 additional articles identified through reference list manual searches. Six articles represented 5 guidelines and 15 described interventions. All guidelines endorsed the applicability of general HF guidelines to NH residents, tailored to comorbidities, frailty, and advance care preferences. Four addressed quality assurance but not feasibility and sustainability. Methodological quality of the interventions was poor, although results suggest that guideline-based HF management in NHs can improve nursing staff knowledge and job satisfaction, prescribing, and reduce acute care utilization. Clinically-based education for staff, and access to specialist mentorship are important. NH physician involvement was limited, and resident/family education potentially ineffective. Concerns about feasibility, sustainability, and quality assurance were identified in most interventions, and advance care planning was rarely addressed. HF guidelines for NH support the applicability of general HF guidelines to the care of NH residents, and published interventions suggest that guideline-based HF management in NHs is effective. Future work should support greater physician and resident engagement, advance care planning, and provide robust guidelines on developing feasible and sustainable interventions. 相似文献
39.
Ashlay A. Huitema Karen Harkness George A. Heckman Robert S. McKelvie 《The Canadian journal of cardiology》2018,34(7):863-870
Heart failure (HF) is a significant public health concern. Specialized HF clinics provide the optimal environment to address the complex needs of these patients and improve outcomes. The current and growing population of patients with HF outstrips the ability of these clinics to deliver care. Integrated care is defined as health services that are managed and delivered so that people receive a seamless continuum of health promotion, disease prevention, diagnosis, treatment, disease management, rehabilitation, and palliative care services. This approach requires coordination across different levels and sites of care within and beyond the health sector, according to changing patient needs throughout their lives. The spoke-hub-and-node (SHN) model represents an organization of care that works collaboratively with the primary care sector and is highly integrated with community-based multidisciplinary teams of health care professionals and specialty care. The purpose of this article is to analyze the requirements for successful implementation of SHN models. We consider the respective roles of HF clinics, HF nurse specialists, pharmacists, palliative care teams, telemonitoring, and solo practitioners. We also discuss levels of care delivery and the importance of patient stratification and patient flow. The SHN approach has the potential to build on and improve the chronic care model (CCM) to deliver centralized services to preserve high-quality patient-centred care at affordable costs. 相似文献
40.
Chronic myelocytic leukemia (CML) may display a lymphoproliferative phase (lymphoid blast crisis) that is generally of B cell phenotype. Since lymphoproliferative disorders may occur following bone marrow transplantation (BMT), it may be difficult to distinguish posttransplant relapse of CML lymphoid blast crisis from de novo lymphoproliferation. Lymphoid blast crisis cells from a patient with CML displayed immunoglobulin heavy chain gene (C mu) rearrangement before BMT. Following BMT the patient developed a lymphoproliferative disorder involving multiple organs. Clonal rearrangement of C mu was demonstrated in several involved tissues. The rearranged C mu restriction fragment was distinct from that displayed before BMT. Additionally, rearrangement of the breakpoint cluster region (bcr) was demonstrated in the pretransplant blast crisis sample, but not in the posttransplant lymphoproliferation samples, thus confirming that these lymphoproliferative disorders were distinct. Molecular genetic techniques offer powerful diagnostic tools for monitoring the course of patients with CML undergoing BMT. 相似文献