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101.
Specificity of cytotoxic effector cells directed against trinitrobenzene sulfonate-modified syngeneic cells. Failure to recognize cell surface- bound trinitrophenyl dextran
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PA Henkart A Schmitt-Verhulst GM Shearer 《The Journal of experimental medicine》1977,146(4):1068-1078
Mouse splenic lymphocytes and lymphoid tumor cells were modified with the trinitrophenyl (TNP) group either by treatment with trinitrobenzene sulfonate (TNBS) (which covalently modifies cell surface proteins) or with TNP stearoyl dextran (TSD) (which binds to the cell by noncovalent forces). These cell preparations were compared for their ability to: (a) sensitive syngeneic splenic lymphocytes leading to the generation of cytotoxic effector cells; (b) serve as lysable targets in a 4-h(51)Cr- release assay for effector cells generated in (a); and (c) act as blocking cells in the lysis of TNBS-medified targets lysed by TNP self effector cells generated in (a). In none of these three experimental systems did TSD-medified syngeneic spleen or H-2-matched tumor cells act either as a sensitizing immunogen or as a target antigen, despite the demonstration that quantitatively equivalent mounts of TNP were exposed on the cell surface in the TNBS- and TSD-modified cells. In contrast, TNBS-modified spleen cells sensitized syngeneic lymphocytes to generate effectors against TNBS-modified syageneic targets. Furthermore, TNBS- modified, H-2-matched cells served as specific lysable targets and as inhibiting cells for such effectors. These results indicate that the manner in which TNP is associated with the cell surface is important in the immunogenicity and antigenicity of hapten-modified syngeneic stimulating cells in generating H-2-associated cell-mediated lympholysis (CML) reactions. These findings raise the possibility that a covalent or at least a stable linkage with cell surface proteins (possibly H-2- controlled products) is important for immunological function. Furthermore, these observations do not favor the dual receptor model for H-2-restricted syngeneic CML if it is assumed in such a model that one receptor is specific for the TNP moiety and the second for unmodified self major histocompatibility products. 相似文献
102.
Inflammatory bowel disease and the X chromosome 总被引:1,自引:0,他引:1
Hayward PA; Satsangi J; Jewell DP 《QJM : monthly journal of the Association of Physicians》1996,89(9):713-718
A review of documented cases demonstrates a significant association of
Turner's syndrome with Crohn's disease and ulcerative colitis; this
association relates particularly to genetic constitutions comprising an
abnormal rather than an absent X chromosome. The karyotype 46XiXq, in pure
or mosaic form, appears to be a significant susceptibility factor for
inflammatory bowel disease. This karyotype often gives rise to relatively
weak phenotypic characteristics of Turner's syndrome, which may be
overlooked in short females with inflammatory bowel disease. The
association of inflammatory bowel disease with Turner's syndrome may
reflect the presence on the X chromosome of genes involved in disease
pathogenesis. Linkage analysis studies, involving microsatellite markers on
the X chromosome, are being performed.
相似文献
103.
Expression and function of receptors for stem cell factor and erythropoietin during lineage commitment of human hematopoietic progenitor cells 总被引:2,自引:0,他引:2
The aim of the present study was to determine whether stem cell factor (SCF) and erythropoietin (EPO) act differently on defined subsets of progenitor cells, and if potential differences correlate with the receptor density on each subset. To investigate this possibility directly, we optimized conditions for the identification and purification of homogeneous progenitor cell subpopulations from human bone marrow. Populations containing 40% and 44% colony forming cells (CFCs) with 99% and 95% purity for the granulomonocytic and erythroid lineage, respectively, were sorted on the basis of differential expression of CD34, CD64, and CD71. In addition, a population containing 67% CFCs, of which 29-43% were CFU-MIX, was sorted from CD34hi CD38loCD50+ cells. Purified progenitor cell subsets were compared directly for responsiveness to SCF and EPO using a short-term proliferation assay. Expression of the receptors for SCF and EPO were then examined on each subset using a flow cytometer modified for high- sensitivity fluorescence measurements. The results show that EPO induces extensive proliferation of erythroid progenitor cells, but has no effect on the proliferation or survival of primitive or granulomonocytic progenitors, even when used in combination with other cytokines. The majority of erythroid progenitor cells furthermore stained positively with anti-EPO receptor (EPO-R) monoclonal antibodies, whereas other progenitor cells were negative. SCF alone induced extensive proliferation of erythroid progenitor cells, and had a stronger synergistic effect on primitive than on granulo-monocytic progenitors. In spite of these differences in SCF activity, there were no significant differences in SCF-R expression between the progenitor subsets. These results suggest that the selective action of EPO on erythropoiesis is determined by lineage-restricted receptor expression, whereas there are additional cell-type specific factors that influence progenitor cell responses to SCF. 相似文献
104.
For convenience, small volumes of platelet concentrate (PC) intended for neonatal patients are often dispensed in syringes. The PC, however, may remain in the syringe for up to several hours before the actual transfusion. As there are few data on the effect of such syringe storage on PCs, the in vitro syringe storage properties of small volumes of 1- and 5-day-old units, and volume-reduced units of PC were evaluated. In four separate experiments, PCs were stored in syringes in volumes of 10, 15, or 30 mL for up to 6 hours at 20 to 24 degrees C without agitation. Platelets were evaluated for pH, platelet count, and a variety of biochemical and in vitro functional assays. Results showed that even with the equivalent of a full unit of platelets stored in the syringe for up to 6 hours, the pH did not fall below 6.0. Although there was an increase in lactate production and consumption of glucose, which paralleled the decline in pH, the changes were not greater than those seen in platelets stored up to 5 days in gas-permeable blood bags. Similar results were seen for PCs stored in syringes for 6 hours at 37 degrees C. All of the pH levels recorded at the end of 6 hours of syringe storage were above the minimum required level of pH 6.0. Data from in vitro platelet assays imply that at any time during their shelf life, PCs can be stored in gas-impermeable polypropylene syringes for up to 6 hours and can maintain acceptable storage characteristics; in vivo data are needed to confirm these observations. 相似文献
105.
目的 对比分析锡伯族、汉族冠心病患者颈动脉粥样硬化及冠状动脉病变情况.方法 对经冠状动脉造影明确的48例锡伯族、57例汉族冠心病患者和50例正常对照者均行颈动脉超声检查,比较各组间颈动脉内膜中膜厚度、斑块的发生率及冠状动脉病变的Gensini积分.结果 锡伯族、汉族冠心病患者内膜中膜厚度及颈动脉斑块的发生率均高于正常对照者(1.1±0.3 mm和1.0±0.1 mm比0.6±0.2 mm、88.3%和77.2%比38.0%,P<0.05),但锡伯族与汉族间比较没有统计学差异(P>0.05);锡伯族患者冠状动脉病变支数少于汉族(1.82±0.24比2.54±0.31, P<0.05),冠状动脉病变的Gensini积分也明显低于汉族(8.23±1.35比15.84±2.68,P<0.05),且冠状动脉病变支数越多,锡伯族、汉族冠心病患者颈动脉粥样硬化程度越重.结论 锡伯族和汉族冠心病患者颈动脉粥样硬化情况均重于正常对照者,但锡伯族和汉族间比较没有统计学意义;锡伯族和汉族冠心病患者冠状动脉病变存在差异,且锡伯族冠心病患者冠状动脉病变严重程度低于汉族;通过颈动脉内膜中膜厚度的程度可预测冠状动脉病变的存在及严重程度. 相似文献
106.
J Vesper E Bölke C Wille PA Gerber C Matuschek M Peiper HJ Steiger W Budach G Lammering 《European journal of medical research》2009,14(3):93-101
Stereotactic radiosurgery is related to the history of "radiotherapy" and "stereotactic neurosurgery". The concepts for neurosurgeons and radiooncologists have been changed during the last decade and have also transformed neurosurgery. The gamma knife and the stereotactically modified linear accelerator (LINAC) are radiosurgical equipments to treat predetermined intracranial targets through the intact skull without damaging the surrounding normal brain tissue. These technical developments allow a more precise intracranial lesion control and offer even more conformal dose plans for irregularly shaped lesions. Histological determination by stereotactic biopsy remains the basis for any otherwise undefined intracranial lesion. As a minimal approach, it allows functional preservation, low risk and high sensitivity. Long-term results have been published for various indications. The impact of radiosurgery is presented for the management of gliomas, metastases, brain stem lesions, benign tumours and vascular malformations and selected functional disorders such as trigeminal neuralgia. In AVM''s it can be performed as part of a multimodality strategy including resection or endovascular embolisation. Finally, the technological advances in radiation oncology as well as stereotactic neurosurgery have led to significant improvements in radiosurgical treatment opportunities. Novel indications are currently under investigation. The combination of both, the neurosurgical and the radiooncological expertise, will help to minimize the risk for the patient while achieving a greater treatment success. 相似文献
107.
E Bölke K Orth PA Gerber G Lammering R Mota M Peiper C Matuschek W Budach E Rusnak S Shaikh B Dogan HB Prisack H Bojar 《European journal of medical research》2009,14(8):359-363
Background
Breast cancer (BC) represents one of the leading causes of cancer related deaths worldwide. New tools for diagnostic staging and therapeutic monitoring are needed to improve individualized therapies and improve clinical outcome. The analyses of circulating tumour cells may provide important prognostic information in the clinical setting.Materials and methods
Circulating tumour cells (CTC) of 63 BC patients were isolated from peripheral blood (PB) through immunomagnetic separation. Subsequently, RT-PCR or mPCR for the genes ga733.2, muc-1, c-erbB2, mgb-1, spdef and c-erbB2 were performed. Subsequently, expression data were correlated with the tumour stages. Fourteen healthy individuals served as controls.Results
Significant correlations with tumour stages were found in single gene analyses of ga733.2, muc-1 and in multi-gene analyses of ga733.2/muc-1/mgb1/spdef. Furthermore, a significant correlation of Ca 15-3 and all studied genes was also observed.Conclusion
Herein, we demonstrated a positive correlation of a gene signature consisting of ga733.2, muc-1, mgb1 and spdef and advanced stages of BC. Moreover, all studied genes and gene patterns revealed a significant correlation with Ca 15-3 positive cases. 相似文献108.
109.
Background and purpose:
In vitro evidence suggests that metabolism of anandamide by cyclooxygenase-2 (COX-2) may be more important when the primary metabolic pathway [i.e. fatty acid amide hydrolase (FAAH)] is inhibited. Thus, the first aim of the present study was to assess the effects of COX-2 and/or FAAH inhibition, on the cardiovascular actions of anandamide. The second aim was to compare the effects of anandamide with those of the metabolically stable analogue (i.e. methanandamide) and investigate mechanisms involved in responses to the latter in conscious rats.Experimental approach:
Rats were chronically instrumented for recording blood pressure, heart rate and renal, mesenteric and hindquarters vascular conductances in the freely moving state.Key results:
Inhibition of FAAH with URB597 (cyclohexycarbamic acid 3′-carbamoyl-biphenyl-3-yl-ester) augmented the haemodynamic actions of anandamide, but there was no effect of COX-2 inhibition with parecoxib, either in the absence or the presence of URB597. Methanandamide caused CB1 receptor-mediated renal and mesenteric vasoconstriction and evoked β2-adrenoceptor-mediated hindquarters vasodilatation.Conclusions and implications:
No evidence for an involvement of COX-2 in the systemic cardiovascular actions of anandamide could be demonstrated. Vasoconstrictor actions of methanandamide were shown to involve CB1 receptors, whereas no involvement of CB1 receptors in such actions of anandamide has been shown. However, β2-adrenoceptor-mediated hindquarters vasodilatation, independent of CB1 receptors, observed here with methanandamide, has previously been seen with anandamide and differs from previous results with other synthetic cannabinoids for which the response was CB1 receptor-dependent. Thus, mechanisms underlying the cardiovascular actions of endocannabinoids and synthetic analogues appear to be agonist-specific. 相似文献110.
Z Luo Y Chen S Chen WJ Welch BT Andresen PA Jose CS Wilcox 《British journal of pharmacology》2009,157(6):935-943