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101.
Price  TH; Chatta  GS; Dale  DC 《Blood》1996,88(1):335-340
Recombinant granulocyte colony-stimulating factor (G-CSF) was administered to healthy young (n = 32) and elderly (n = 19) volunteers (0 microgram/d, 30 microgram/d, or 300 microgram/d) to determine its effect on neutrophil production, blood kinetics, and tissue migration. Measurements included blood counts (daily), marrow neutrophil pool sizes and neutrophil tissue migration (baseline and day 5), blood kinetics (day 6), and marrow transit time while on drug (days 6 to 14). G-CSF markedly expanded the marrow neutrophil mitotic pool and shortened the transit time of the postmitotic pool (control, mean = 6.4 days; 300 microgram/d, mean = 2.9 d). G-CSF increased neutrophil production without significantly altering blood neutrophil half-life or margination. Compared to control, neutrophil accumulation in skin chambers decreased by about 50% in the 300 microgram/d group in both young and elderly subjects. G-CSF induced neutrophilia by stimulating proliferation of marrow neutrophil precursors and accelerating neutrophil entry into the blood. Decreased neutrophil inflammatory responses measured with the skin chamber technique may be because of the relative immaturity of the circulating cells or to alterations in neutrophil phenotype induced by G-CSF.  相似文献   
102.
Case  DC Jr 《Blood》1982,59(5):934-937
Fourteen consecutively referred, symptomatic patients with Waldenstrom's macroglobulinemia (ages 52-87 yr) have been treated with the 5-drug M-2 protocol (BCNU, cyclophosphamide, vincristine, melphalan, and prednisone). Three patients were previously treated and 11 patients were untreated. The majority of patients were symptomatic from hyperviscosity. All patients have responded to therapy. Two patients have achieved complete remissions and 12 patients partial remissions to date. None of the patients with symptomatic hyperviscosity has required plasmapheresis since therapy with the M-2 has been initiated. Lymphadenopathy, hepatosplenomegaly, and anemia have also responded to treatment. Follow-up data are limited, with survival from initiation of therapy with the M-2 ranging from 2+ to 35% mo (median 17+ mo) 2+-40+ mo from time of diagnosis). Combination chemotherapy for Waldenstrom's macroglobulinemia with the M-2 protocol appears to increase the response rate in patients with symptomatic disease. Further survival analysis will be carried out.  相似文献   
103.
The acute leukemia associated with the t(4;11) chromosome rearrangement is characterized by relatively consistent clinical features: occurrence primarily in young individuals, hyperleukocytosis, and poor response to therapy. This study describes the morphological, ultrastructural, and immunologic characteristics of the leukemic cells from ten patients with this type of leukemia. The morphological features of the leukemic blasts vary from lymphoid-appearing to monocytic. Ultrastructurally and cytochemically, some of the lymphoid-appearing blasts possess features of myeloid origin. The immunologic phenotype is characteristically E- SIg- CALLA- BA-1- BA-2+ HLA-DR+ and TdT+. These findings suggest that the t(4;11)-associated acute leukemia represents a proliferation of an early myeloid progenitor cell.  相似文献   
104.
105.
Polymorphonuclear leukocytes (PMN) with a deficiency of the complement receptor type 3 (CR3) membrane glycoprotein family have impairments in the ability to adhere to surfaces as well as chemotactic and phagocytic defects, processes that require a functional contractile apparatus. PMN from the patient with neutrophil actin dysfunction (NAD) displayed similar functional characteristics to those with CR3 deficiency suggesting the two disorders may be the same disease. In order to evaluate the relationship between CR3 deficiency and actin assembly, actin filament assembly was measured in PMN from six previously reported homozygotes (two severe and four moderate CR3-deficient patients) as well as five heterozygotes for CR3 deficiency. PMN from all patients had normal unstimulated concentrations of F-actin and after exposure to the chemotactic peptide FMLP (5 x 10(-7) mol/L for 5 to 40 seconds at 25 degrees C) assembled actin normally. Pretreatment of normal PMN with concentrations of monoclonal anti-alpha CR3 antibody, capable of blocking PMN adherence, also failed to impair FMLP- induced actin filament assembly. CR3 glycoprotein expression was measured in PMNs from the mother, father, and older sister of the NAD patient (N Engl J Med 291:1093, 1974). Actin filament assembly was recently shown to be defective in PMNs from all three family members. The total concentrations of the alpha and beta CR3 subunits were below normal in PMN detergent extracts from the mother (25% of simultaneous controls) and older sister (56% of control). PMN surface expression of these two subunits was also found to be depressed (mother, 50%; older sister, 63% of control). These findings suggest these two NAD family members are heterozygote carriers for CR3 deficiency as well as NAD. Simultaneous studies of the father, however, demonstrated normal total concentrations of both the alpha and beta CR3 subunits (126% of controls) as well as normal surface expression of both subunits after phorbol myristate acetate stimulation and incubation at 37 degrees C (mean, 112% of controls) but slightly lower than normal levels after FMLP stimulation (mean, 83%). These findings indicate that CR3 deficiency generally is not associated with defective actin filament assembly and support the conclusion that NAD represents a unique kindred in which PMN actin function differs from previously reported genotypes of CR3 deficiency.  相似文献   
106.
Twenty-six patients with progressive Hodgkin's disease after conventional chemotherapy received intensive chemoradiotherapy and autologous bone marrow transplantation (ABMT); 19 also received additional involved-field radiotherapy. Twenty-one patients [81%, 95% confidence intervals (CI) 61% to 94%] attained complete (n = 18) or partial responses. Ten patients (38%, 95% CI 20% to 59%) are disease- free a median of 4.5 years later (range 3.5 to 7.0 years), including seven patients with continuous complete responses. The likelihood of overall response was not significantly influenced by any clinical or treatment variable examined. However, there was a trend favoring patients with higher Karnofsky scores, and higher scores were associated with attainment of complete responses (P = .06 and P = .02, respectively, Mann-Whitney U test). Both higher Karnofsky scores and shorter durations of disease before transplantation were associated with improved survival in a stepwise Cox multivariate analysis. The chief cause of failure was progression at sites previously involved with Hodgkin's disease. No patient relapsed in the marrow, and two of three patients with a history of marrow involvement with Hodgkin's disease achieved durable complete responses after transplantation. These data suggest that inadequate pretransplant conditioning, and not the reinoculation of occult tumor cells in the autologous marrow, caused most relapses. Fatal treatment-related toxicity occurred in six patients. Three patients died of idiopathic interstitial pneumonitis; each had previously received local mediastinal irradiation before intensive chemoradiotherapy. Intensive chemoradiotherapy and ABMT produces durable responses in some patients with Hodgkin's disease incurable with conventional therapy. Use of such therapies at the first sign of failure with conventional chemotherapy and development of more effective conditioning regimens should further improve results.  相似文献   
107.
Russo  DC; Lee  S; Reid  M; Redman  CM 《Blood》1994,84(10):3518-3523
Kell is one of the major blood group systems in human red blood cells (RBCs). The Kell antigens are carried on a 731 amino acid glycoprotein that is thought to span the erythrocyte membrane once. Rabbit antibodies to three synthetic peptides, derived from different parts of the Kell protein, were used to determine the topology of Kell protein on the RBC. Antibodies to a C-terminal peptide and to a peptide derived from amino acid residues 410 to 439 reacted with RBCs treated with 0.2 mol/L dithiothreitol. An antibody to the N-terminal peptide reacted with inside-out RBC vesicles but not with right-side-out vesicles nor with intact RBCs, showing that Kell is a type II membrane protein and that the extracellular portion of the protein is folded by disulfide bonds. By transfection, Kell protein was expressed on the cell surface of surrogate cells, and the transfected cells expressed similar antigenic properties as native RBCs. Kell protein was expressed in COS- 1 and K562 cells and in Sf9 cells infected by the Baculovirus system. Transfected K562 cells expressed several high-incidence antigens but not the low-incidence antigen K1.  相似文献   
108.
Human neonatal neutrophils manifest decreases in mobility, adherence, and emigration compared with adult neutrophils that may contribute to the increased susceptibility of neonates to infection. In a developmental rabbit model, we show a reduced ability of neutrophils from 1-day-old rabbit pups to emigrate to inflamed peritoneium (3.7 +/- 0.35 x 10(6) neutrophils/mL peritoneal exudate) compared with 14-day- old (8.5 +/- 0.7 x 10(6)/mL) and adult rabbits (9.4 +/- 1.4 x 10(6) mL, P < .05) despite significantly increased blood neutrophil counts. Because the reductions in functional Mac-1 (CD11b/CD18) as well as the amount of surface L-selectin are hypothesized to be primarily responsible for the differences in human neonatal neutrophil mobility, we examined CD11b/CD18 and L-selectin in our model. Using flow cytometric analysis we found that similar to human neonates, neutrophils from 1-day-old rabbit pups had 57% of adult rabbit levels of L-selectin and, in contrast with adults, failed to show significant decreases in L-selectin after chemotactic stimulation. In addition, neutrophils from 1-day-old pups compared with adults showed a significantly diminished capacity to upregulate CD11b/CD18 after chemotactic stimulation in vitro, or after emigration to the inflamed peritoneum. Systemic administration of anti-L-selectin monoclonal antibody (MoAb) resulted in significant reduction in peritoneal neutrophils in adult (47%, P < .05) and 14-day-old rabbits (47%, P < .05), but was without effect in 1-day-old rabbits. Administration of anti-CD18 MoAb resulted in significant reduction in peritoneal neutrophil accumulation in all age groups though less in 1 day and 14 day (58% and 65%, respectively) than in adults (91%, P < .05). Only in the 14-day-old rabbits was there an additive effect of anti-L-selectin and anti-CD18 MoAbs compared with anti-CD18 alone (84% v 65%, P < .05). The findings in this in vivo rabbit model support the hypothesis that the previously described in vitro defects in human neonatal L-selectin and CD11b/CD18 may be major contributors to human neonatal inflammatory deficits.  相似文献   
109.
Rising demand for single-donor platelet components–from random donors, to maintain platelet inventories, or from HLA-compatible donors, to support alloimmune platelet-refractory patients–necessitated increasing the size of a community plateletpheresis donor registry. This study compares two strategies for recruiting whole-blood donors into a plateletpheresis program. The whole-blood donors who were asked to participate in this study had recently joined an unrelated bone marrow donor registry and had been HLA-typed as part of that process. An in-person recruitment strategy, which was time-intensive for the apheresis donor coordinator, served as the standard. A by-mail strategy involved the mailing of recruitment materials to marrow-donor registry participants. Marrow-donor registry participants were approached about apheresis participation after they had indicated an interest in the plateletpheresis program by returning a tear-off section of an informational brochure that was sent to them along with their marrow- donor registry materials. A total of 852 marrow-donor registry participants were randomly assigned to one of two recruitment strategies, and the recruitment rates were the same (46%) for both methods. In addition, levels of apheresis participation and attrition rates of donors recruited by either strategy were comparable. Thus, the simple strategy of mailing information about a plateletpheresis program is a very cost-effective method of recruiting donors.  相似文献   
110.
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