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91.
92.
A technique for the flow cytometric analysis of lymphocytes bearing histamine receptors 总被引:2,自引:0,他引:2
Histamine receptors have been demonstrated on lymphocyte membranes by a variety of techniques. We now report a method that allows for the flow cytometric analysis of histamine receptors on human peripheral T cells. Histamine is conjugated to fluoresceinated human albumin by the coupling agent ECDI. This conjugated histamine compound (FHA-his) binds to approximately 45% of T cells. Fluoresceinated human albumin alone (FHA), not conjugated to histamine, does not bind to T cells. In addition, unconjugated histamine can inhibit completely the binding seen with FHA-his. We conclude that this technique demonstrates specific FHA-his binding to histamine receptors on T cells and can be used to determine the number of cells bearing such receptors. In addition, the reagent could be used with a cell sorter to isolate distinct histamine-receptor-bearing (HR+) cells for further immunologic study. 相似文献
93.
Wolff SN; Marion J; Stein RS; Flexner JM; Lazarus HM; Spitzer TR; Phillips GL; Herzig RH; Herzig GP 《Blood》1985,65(6):1407-1411
High-dose (HD) cytosine arabinoside (ARA-C) is more effective treatment than conventional-dose ARA-C regimens for patients with relapsed acute nonlymphocytic leukemia (ANLL). We report here that HD ARA-C given during the first remission of ANLL has resulted in long remission durations and a high proportion of patients who survive more than three years free of disease. From August 1979 to September 1983, 36 adult patients with ANLL in first remission received one to three courses of HD ARA-C (3 g/m2 by one-hour infusion every 12 hours for 12 doses on days 1 through 6) alone or with daunorubicin (30 mg/m2 for two or three doses on days 7 through 9). Three patients died of sepsis or hemorrhage during consolidation, and 14 patients have relapsed from five to 48 months after diagnosis. The remaining 19 patients are in continued complete remission (CCR) from 11 to 62 months. Denoting all deaths in remission as relapse, the actuarial probability of CCR is 42% at 62 months, with an apparent plateau in the survival curve. Of the first 22 patients treated, ten remain in CCR from 37 to 62 months with no therapy for at least three years. Due to its heightened anti-leukemic activity, HD ARA-C allows brief but effective consolidation of ANLL in first remission, with long-term disease-free survival comparable to other approaches. 相似文献
94.
Sickle erythrocyte-endothelial interactions in microcirculation: the role of von Willebrand factor and implications for vasoocclusion 总被引:1,自引:0,他引:1
To determine the role of von Willebrand factor (vWF) in adhesion of sickle (SS) erythrocytes in microvascular flow conditions, we have perfused the ex vivo mesocecum vasculature of the rat with desmopressin, an analogue of vasopressin that causes the release of endothelial vWF. Analysis of vWF in the venous effluent of the isolated vasculature showed mainly the presence of extra-large molecular weight forms characteristic of endothelial vWF, which in the presence of desmopressin showed an average increase of 54%. Also, desmopressin induced a significant increase in adhesion of washed oxygenated (oxy) unseparated SS erythrocytes, accompanied by a persistent microvascular obstruction and a pronounced increase in the peripheral resistance (PRU). In contrast, infusion of SS deformable discocytes (SS2) in desmopressin-perfused vasculature resulted in a significant adhesion but not in persistent vasoocclusion, showing that SS2 discocytes alone are not sufficient for microvascular obstruction. Furthermore, SS4 erythrocytes (dense discocytes and irreversibly sickled erythrocytes) caused a persistent microvascular blockage and a significantly higher PRU than SS2 discocytes. However, the increase in PRU for SS4 erythrocytes following desmopressin treatment was 50% less compared with a corresponding increase for SS2 discocytes over the control values, which showed a smaller effect of desmopressin on the hemodynamic behavior of SS4 dense erythrocytes. Incubation of desmopressin-treated vasculature with anti-vWF antibodies resulted in a pronounced decrease in adhesion and significantly improved hemodynamic behavior of SS cells. Also, in untreated vasculature, similarly incubated with anti-vWF antibodies, there was almost complete inhibition of adhesion. Under the described perfusion conditions, antibodies to fibronectin and thrombospondin, as well as incubation of SS erythrocytes with anti-vWF antibodies did not affect adhesion. These results are compatible with a model for SS vasoocclusion in which extra- large vWF-mediated adhesion of deformable SS erythrocytes is the first step followed by an accelerated entrapment of dense SS erythrocytes. 相似文献
95.
Previous studies on the association of ankylosing spondylitis and
abnormalities of the lung parenchyma have been based largely on plain
radiography and pulmonary function testing. This study, although
uncontrolled, is the first to use high-resolution computed tomography to
examine the entire lung parenchyma in ankylosing spondylitis patients, and
to correlate the findings with clinical assessment, plain radiography and
pulmonary function testing. The study population comprised 26 patients
meeting the New York criteria for idiopathic ankylosing spondylitis who
attended the out-patient department at our institution. High-resolution
computed tomography examination revealed abnormalities in 19 patients
(70%): these included interstitial lung disease (n = 4), bronchiectasis (n
= 6), emphysema (n = 4), apical fibrosis (n = 2), mycetoma (n = 1) and
non-specific interstitial lung disease (n = 12). Plain radiography was
abnormal in only four patients and failed to identify any patient with
interstitial lung disease. All patients with interstitial lung disease on
high-resolution computed tomography had respiratory symptoms and three of
the four had evidence of a restrictive process on pulmonary function
testing. This study raises, for the first time, the possible association
between interstitial lung disease and ankylosing spondylitis, and
highlights the use of high-resolution computed tomography in detecting such
disease in ankylosing spondylitis patients.
相似文献
96.
Interleukin 1 induces human marrow stromal cells in long-term culture to produce granulocyte colony-stimulating factor and macrophage colony- stimulating factor 总被引:11,自引:0,他引:11
Fibbe WE; van Damme J; Billiau A; Goselink HM; Voogt PJ; van Eeden G; Ralph P; Altrock BW; Falkenburg JH 《Blood》1988,71(2):430-435
Pure interleukin 1 (IL 1) was found to stimulate established human bone marrow stromal layers in long-term culture to produce colony- stimulating activity (CSA). Maximal concentrations in the culture medium were reached 24 hours after a single IL 1 pulse. The effect could be neutralized by a specific rabbit anti-IL 1 antiserum. Stromal layers, once stimulated by IL 1, continued to release CSA into the culture medium in the absence of exogenous IL 1. A second IL 1 pulse induced CSA release in an identical manner, as did the primary stimulation, indicating that the CSA released was actively produced. Using specific immunologic assays, both granulocyte colony-stimulating factor (G-CSF) and macrophage CSF (M-CSF) could be identified in the culture supernatants, and production of both factors was inducible by IL 1. Shortly after initiation of the long-term marrow cultures "spontaneous" G-CSF and M-CSF release occurred. The release of G-CSF diminished following addition of the anti-IL 1 antiserum, indicating that endogenous production of IL 1 by stromal cells had contributed to this effect. These results further support the role of IL 1 as an important modulator of CSF production by cells of the hematopoietic microenvironment. 相似文献
97.
Hepatitis C virus infection and chronic liver disease in children with leukemia in long-term remission 总被引:2,自引:0,他引:2
Locasciulli A; Gornati G; Tagger A; Ribero ML; Cavalletto D; Cavalletto L; Masera G; Shulman HM; Portmann B; Alberti A 《Blood》1991,78(6):1619-1622
Antibody to the recently identified hepatitis C virus (HCV) was investigated in sera of 50 leukemic children who had chronic liver disease (CLD), observed for 1 to 12.6 years after therapy withdrawal. All patients were tested for anti-HCV at regular intervals: Ortho- enzyme-linked immunosorbent assay (ELISA) test was performed in all cases. Reactive sera were also tested by recombinant immunoblotting assay to define the specificity of the results obtained by ELISA. Twelve cases (24%) were persistently positive (group A), 11 (22%) were transiently anti-HCV+ positive (group B), and 27 (54%) were negative. Mean SGPT peak during follow-up was significantly higher in group A (P = .014, A v B and P less than .00001, A v C). SGPT normalized off- therapy in 1 of 12 cases (group A), 10 of 11 (group B), and 19 of 27 (group C) (P = .0004, A v B and P = .012, A v C). Accordingly, liver histology, available in 37 patients, showed signs of chronic hepatitis in all patients in group A while most patients in group B and C had less severe liver lesions. These results indicate that HCV plays a significant role in the etiology of chronic hepatitis in leukemic patients and that persistent anti-HCV activity correlates with a more severe CLD, which could jeopardize the final prognosis of children cured of leukemia. 相似文献
98.
99.
Chen HM; Zhang P; Voso MT; Hohaus S; Gonzalez DA; Glass CK; Zhang DE; Tenen DG 《Blood》1995,85(10):2918-2928
100.
Dercksen MW; Weimar IS; Richel DJ; Breton-Gorius J; Vainchenker W; Slaper- Cortenbach CM; Pinedo HM; von dem Borne AE; Gerritsen WR; van der Schoot CE 《Blood》1995,86(10):3771-3782
In the present study, we show by adhesion assays and ultrastructural studies that platelets can bind to CD34+ cells from human blood and bone marrow and that this interaction interferes with the accurate detection of endogenously expressed platelet glycoproteins (GPs). The interaction between these cells was found to be reversible, dependent on divalent cations, and mediated by P-selectin. Enzymatic characterization showed the involvement of sialic acid residues, protein(s). The demonstration of mRNA for the P-selectin glycoprotein ligand 1 (PSGL-1) in the CD34+ cells by polymerase chain reaction (PCR) analysis suggests that this molecule is present in these cells. Under conditions that prevent platelet adhesion, a small but distinct subpopulation of CD34+ cells diffusely expressed the platelet GPIIb/IIIa complex. These cells were visualized by immunochemical studies. Furthermore, synthesis of mRNA for GPIIb and GPIIIa by CD34+ cells was shown using PCR analysis. The semiquantitative PCR results show relatively higher amounts of GPIIb mRNA than of PF4 mRNA in CD34+CD41+ cells in comparison with this ratio in platelets. This finding is a strong indication that the PCR results are not caused by contaminating adhering platelets. MoAbs against GPIa GPIb alpha, GPV, P- selectin, and the alpha-chain of the vitronectin receptor did not react with CD34+ cells. The number of CD34+ cells expressing GPIIb/IIIa present in peripheral blood stem cell (PBSC) transplants was determined and was correlated with platelet recovery after intensive chemotherapy in 27 patients. The number of CD34+CD41+ cells correlated significantly better with the time of platelet recovery after PBSC transplantation (r = .83, P = .04) than did the total number of CD34+ cells (r = .55). Statistical analysis produced a threshold value for rapid platelet recovery of 0.34 x 10(6) CD34+CD41+ cells/kg. This study suggests that if performed in the presence of EDTA the flow cytometric measurement of GPIIb/IIIa on CD34+ cells provides the most accurate indication of the platelet reconstitutive capacity of the PBSC transplant. 相似文献