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191.
Expression of murine CD38 defines a population of long-term reconstituting hematopoietic stem cells 总被引:5,自引:6,他引:5
Using a monoclonal antibody to murine CD38, we showed that a population of adult bone marrow cells that expressed the markers Sca-1 and c-kit but lacked the lineage markers Mac-1, GR-1, B220, IgM, CD3, CD4, CD8 and CD5 could be subdivided by the expression of CD38. We showed that CD38high c-kit+ Sca-1+, linlow/-cells sorted from adult bone marrow cultured with interleukin-3 (IL-3), IL-6, and kit-L produced much larger colonies in liquid culture at a greater frequency than their CD38low/- counterparts. In addition, we found that CD36low/ - cells contained most of the day-12 colony-forming units-spleen (CFU-S) but were not long-term reconstituting cells, whereas the population that expressed higher levels of CD38 contained few, but significant, day-12 CFU-S and virtually all the long-term reconstituting stem cells. Interestingly, the CD38high Sca-1+ c-kit+ linlow/- cells isolated from day-E14.5 fetal liver were also found to be long-term reconstituting stem cells. This is in striking contrast to human hematopoietic progenitors in which the most primitive hematopoietic cells from fetal tissues lack the expression of CD38. Furthermore, because antibodies to CD38 could functionally replace antibodies to Thy-1.1 in a stem cell purification procedure, the use of anti-CD38 may be more generally applicable to the purification of hematopoietic stem cells from mouse strains that do not express the Thy-1.1 allele. 相似文献
192.
Dr. Nicola Pietra M.D. Leopoldo Sarli M.D. Giuliano Sansebastiano B.S. Gloria Saccani Jotti M.D. Anacleto Peracchia M.D. 《Diseases of the colon and rectum》1996,39(5):494-503
PURPOSE: The aim of this study was to obtain additional biologic determinants that may be of use in segregating into subgroups with different prognosis patients with similarly staged colorectal cancers. METHODS: Between 1989 and 1991, a prospective study of prognostic factors has been performed in a group of 98 consecutive, unselected patients who underwent curative resections for primary untreated large bowel carcinoma. The fate of all patients is known at three years after operation. Clinical and pathologic data were recorded at the time of presentation and operation, and patients have been the subjects of regular follow-up. Tumor DNA content was determined by flow cytometry, and cell proliferative activity was determined by autoradiography with tritiated thymidine labeling index (LI). RESULTS: Univariate analysis revealed that the most important predictors of survival (P<0.001) were the presence of positive lymph nodes, the presence of preoperative complications, Dukes stage, and LI. The multivariate analysis showed that Dukes stage (P<0.002) and LI(P<0.0001) were the only factors significantly related to survival. Disease-free survival was influenced significantly by Dukes stage (P<0.001), LI, according to the classification in the two groups of high and low proliferative activity, respectively, (P<0.0001), LI, calculated as a continuous variable (P<0.0002), and the presence of lymph node metastases (P<0.003). Outcome (favorable/unfavorable) was influenced significantly by Dukes stage (P<0.0001) and LI (P<0.0001). Concordance for each patient between Dukes stage and outcome was 73.1 percent and between LI, calculated as a continuous variable, and outcome was 74.1 percent. If, on the other hand, Dukes stage and LI are used together, concordance with outcome reaches 89.2 percent. CONCLUSION: We can conclude that, from a practical point of view, LI is an essential factor that must be combined with pathologic variables for a better prediction of patient outcome. 相似文献
193.
Report: workshop on mediastinal grey zone lymphoma 总被引:2,自引:0,他引:2
Sibrand Poppema Joost L Kluiver Cigdem Atayar Anke van den Berg reas Rosenwald Michael Hummel Dido Lenze Hetty Lammert Harald Stein Stephan Joos Thomas Barth Martin Dyer Peter Lichter Uwe Klein Giorgio Cattoretti Annunziata Gloghini Yuhai Tu Gustavo A Stolovitzky rea Califano Antonino Carbone Ricardo Dalla-Favera Ingo Melzner Alexandra J Bucur Silke Brüderlein Karola Dorsch Cornelia Hasel Thomas FE Barth Frank Leithäuser Peter Möller 《European journal of haematology》2005,75(S66):45-52
Abstract: There are several indications that classical Hodgkin lymphoma (cHL) and at least a proportion of cases of Primary Mediastinal B cell Lymphoma (PMBL) are derived from B cells at similar stages of differentiation and share common pathogenic mechanisms. The first indication was the existence of mediastinal grey zone lymphomas as identified in the 4th International Symposium on HL, with clinical, histological and immunohistochemical features intermediate between cHL and PMBL. Second, both tumor types resemble a cell that is developmentally situated in-between the germinal center reaction and a plasma cell. Third, cHL and PMBL were found to have similar gene expression profiles, including the lack of immunoglobulin expression and low levels of B cell receptor signalling molecules, and the secretion of molecules like the chemokine TARC and the prominent expression of IL-13 receptors. Fourth, both entities were found to have common genomic aberrancies, notably in 2p15 and 9p24, the sites of the REL oncogene and the tyrosine kinase gene JAK2, respectively. Further comparison of both lymphoma types may provide further insight in the pathogenic mechanisms and allow the design of diagnostic algorithms to sort out the small number of so-called mediastinal grey zone lymphomas, that appear to be intermediate between PMBL and cHL. 相似文献
194.
Predictive markers of chronic liver disease in hemophilia 总被引:1,自引:0,他引:1
In an attempt to predict progressive liver damage in hemophiliac patients by noninvasive means, we conducted a retrospective analysis of clinical and laboratory data from 44 liver biopsies taken from 35 hemophiliac patients. This showed that serum IgG was normal in patients with chronic persistent hepatitis (CPH) but significantly elevated in those with chronic active hepatitis (CAH) or cirrhosis (CIR) (P less than .001). Relationships were less significant between liver histology and IgM (P less than .01), IgA (P less than .05), and globulin (P less than .05). This was unaffected by human immunodeficiency virus (HIV) antibody status in asymptomatic individuals. Although patients with progressive liver disease were also older than those with CPH (P less than .001), the immunoglobulin abnormalities were independent of this. Neither clinical examination nor liver biochemistry at the time of biopsy were of significant diagnostic value. Our results indicate that in the absence of AIDS an elevated IgG level is a reliable indicator of progressive hemophilic liver disease. 相似文献
195.
P Devine ; FE Dawson ; TL Motschman ; KJ Skradski ; L Orsini ; JJ Moulds ; HF Taswell 《Transfusion》1988,28(4):346-349
Sera from three unrelated persons whose red cells (RBC) had the common Scianna phenotype (Sc:1,-2) contained IgG alloantibodies directed against high-frequency RBC antigens. In each case, sera or eluates or both failed to react only with Scianna null (Sc:-1,-2) cells, although an eluate from one person was compatible with a sibling's Sc:1,-2 cells. Cross-testing cells with sera or eluates, or both, from the three persons revealed no mutual compatibility. These studies show the existence of three additional RBC antigens phenotypically related to the Scianna blood group system. Sc:-1,-2 cells lack these antigens, which indicates that Scianna null cells lack multiple high-frequency antigens. 相似文献
196.
FE Xavier J Blanco-Rivero M Ferrer G Balfagón 《British journal of pharmacology》2009,158(7):1787-1795
Background and purpose:
Prostacyclin (PGI2) is usually described as an endothelium-derived vasodilator, but it can also induce vasoconstriction. We studied the vasomotor responses to PGI2 in resistance arteries and the role of thromboxane (TP) and prostaglandin E2 (EP) receptors in this effect.Experimental approach:
Mesenteric resistance arteries were obtained from Sprague-Dawley rats. Vasomotion to PGI2 was studied in segments of these arteries with and without endothelium and in presence of the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME), the potassium channel blockers apamin plus charybdotoxin, the non-selective EP receptor antagonist AH6809, the selective TP receptor antagonist SQ29548 or the EP1 receptor antagonist SC19220. PGI2-induced NO release was analysed in the absence or presence of SQ29548, AH6809 or SC19220.Key results:
PGI2 caused contractions in arterial segments that were increased by endothelium removal, L-NAME or L-NAME plus apamin plus charybdotoxin and abolished by SQ29548. In segments with endothelium, AH6809 or SC19220 almost abolished the contractions to PGI2; this effect was prevented by L-NAME, L-NAME plus apamin plus charybdotoxin or by endothelium removal. PGI2 induced NO release that was inhibited by the prostacyclin receptor (IP receptor) antagonist, RO1138452, and increased by SQ29548, SC19220 and AH6809. The increase in NO release induced by these separate drugs was inhibited by RO1138452.Conclusions and implications:
PGI2 activated the TP receptor in mesenteric resistance arteries and produced vasoconstriction, which the endothelium modulated through TP and EP1 receptors. PGI2 also released endothelium-derived hyperpolarizing factor and, through IP receptor activation, induced NO release, which in turn, was antagonized by TP and EP1 receptor activation. 相似文献197.
以豚鼠离体回肠和结肠带为标本,观察蛇床子素(Ost)的作用与Ca~(2+)的关系。结果表明:Ost和钙拮抗剂Ver产生剂量依赖性抑制乙酰胆碱(ACh)、组胺及KCl所致回肠条或结肠带的收缩;非竞争性拮抗CaCl_2累积量—效曲线,pD_2分别为4.41±0.15,7.0±0.2。Ost 100μmol/L和Ver 1μmol/L均能对抗小剂量Ca~(2+)所致结肠带收缩,但被加入较大量Ca~(2+)所取消。Ost和Ver均能抑制ACh诱导的依内钙性收缩,不影响依外钙性收缩。结果提示Ost具有钙拮抗作用,其作用方式与Ver类似。 相似文献