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81.
In order to determine whether antigenic patterns alter with disease progression and are thereby suggestive of impending blast crisis in chronic myelogenous leukemia, 50 bone marrow biopsy specimens from 32 patients were examined retrospectively using indirect immunoperoxidase labeling with three monoclonal antibodies that detect myeloid antigens. Monoclonal antibodies PMN13F6, PMN7C3, and PMN8C7 detect human neutrophil antigens that first appear at the myeloblast, promyelocyte, and metamyelocyte stages of differentiation, respectively, and persist throughout later differentiation. Percentages of antigen-positive bone marrow cells during the chronic phase were compared with percentages of antigen-positive cells at blast transformation, and time from bone marrow biopsy until blast crisis was correlated with the percentage of bone marrow cells expressing these antigens. Bone marrow biopsy samples from patients in the chronic phase who continue to remain clinically stable 4 to 106 months after biopsy expressed PMN13F6 antigen on 82% +/- 9% (mean +/- SD) of cells, PMN7C3 antigen on 62% +/- 14% of cells, and PMN8C7 on 68% +/- 14% of cells. Bone marrow biopsy specimens obtained from patients 1 or more years prior to blast transformation expressed PMN13F6 antigen on 81% +/- 12%, PMN7C3 antigen on 71% +/- 16%, and PMN8C7 on 64% +/- 16% of cells. Bone marrow biopsy samples obtained between 2 months and 1 year prior to blast crisis expressed PMN13F6 antigen on 68% +/- 15%, PMN7C3 on 51% +/- 17%, and PMN8C7 antigen on 46% +/- 18% of cells. Bone marrow biopsy specimens taken at the time of blast transformation expressed PMN13F6 antigen on 20% +/- 25%, PMN7C3 antigen on 19% +/- 25%, and PMN8C7 antigen on 13% +/- 25% of cells. The difference between the mean of antigen-positive cells from bone marrow biopsy samples obtained at the time of blast crisis was significant compared with the mean of positive cells from biopsy specimens obtained at all other phases of the disease (P less than .001 for all three antibodies). There was a positive correlation between loss of myeloid antigens and disease progression as determined by simple regression of log time and correlation analysis (PMN13F6, r = .6533, P less than .005; PMN7C8, r = .6304, P less than .005; PMN8C7, r = .5215, P less than .05). There was a negative correlation between percentage of immature cells and time to blastic crisis (r = -.6206, P less than .005).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
82.
BackgroundSerum carotenoids are commonly used as biomarkers of fruit and vegetable (F/V) intake in the general population. Although hyperglycemia induces oxidative stress, it is unknown whether this pathway is associated with lower serum carotenoid concentrations in individuals with type 1 diabetes. Consequently, the utility of serum carotenoids as markers of F/V intake in individuals with type 1 diabetes is unclear.ObjectiveThe study objectives were: 1) to investigate the relationship of glycemic control, oxidative stress, dietary carotenoid and F/V intake with serum carotenoid concentrations in youth with type 1 diabetes and 2) to determine whether glycemic control or oxidative stress moderates the association of carotenoid and F/V intake with serum carotenoids.DesignThe study was a secondary analysis of baseline data from youth with type 1 diabetes. Blood samples were drawn from youth with type 1 diabetes to assess carotenoids and markers of glycemic control (glycated hemoglobin and 1,5-anhydroglucitol); urine samples were used to assess oxidative stress (8-iso-prostaglandin F); and 3-day diet records completed by families were used to determine F/V and carotenoid intake.Participants/settingThe study participants were youth with type 1 diabetes (n=136; age range: 8 to 16.9 years; diabetes duration ≥1 year; glycated hemoglobin: 5.8% to 11.9%) enrolled in a nutrition intervention trial from 2010 to 2013 at a tertiary diabetes center in Boston, MA.Main outcome measuresSerum carotenoids (total carotenoids and α-carotene, β-carotene, lycopene, β-cryptoxanthin, and lutein+zeaxanthin).Statistical analysisRegression analyses were used to estimate the association of glycemic control, oxidative stress, F/V and carotenoid intake with serum carotenoids, as well as the role of glycemic control and oxidative stress in moderating diet-serum carotenoid associations.ResultsGreater F/V intake (β=0.35, P<0.001) and carotenoid intake (β=0.28, P<0.01) were associated with higher total serum carotenoids, and no moderation by glycemic control or oxidative stress was observed. Greater hyperglycemia, as indicated by lower 1,5-anhydroglucitol (β=0.27, P<0.01), was related to lower serum carotenoids; however, glycated hemoglobin was not associated with serum carotenoids. 8-Iso-prostaglandin F2α was not associated with glycemic control or serum carotenoids.ConclusionsFindings support the validity of serum carotenoids as markers of F/V and carotenoid intake in youth with type 1 diabetes.  相似文献   
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85.
Yee  K; Bishop  TR; Mather  C; Zon  LI 《Blood》1993,82(4):1335-1343
Activation of distinct receptor tyrosine kinases (RTK), such as the products of the c-fms and c-kit proto-oncogenes, profoundly affects hematopoietic development. We have isolated a novel RTK cDNA, called met-related kinase (MRK), which is expressed on early erythroid progenitors. MRK is also expressed in many hematopoietic cell lines, and is not lineage restricted. Several regions within the catalytic domain of MRK have amino acid similarity to the c-met proto-oncogene and v-sea oncogene. Specific polyclonal anti-MRK antisera detects an 84- Kd polypeptide in COS cells transfected with an expression vector containing the MRK cDNA. Further studies of this novel RTK will provide potential insight into its role during hematopoiesis.  相似文献   
86.
Ulich  TR; del Castillo  J; Guo  KZ 《Blood》1989,73(1):108-110
Interleukin-6 (IL-6) administered as a single intravenous (IV) injection caused the following changes in the peripheral circulation of rats: (a) a biphasic neutrophilia with an initial peak at 1.5 hours and a second sustained wave of neutrophilia between four and 12 hours, (b) a mild lymphocytosis at 0.5 hours and a mild lymphopenia between 1.5 and four hours, and (c) a reticulocytosis between 12 and 24 hours. The bone marrow showed no significant changes at 1.5 hours, suggesting that the peripheral neutrophilia at that time is caused by demargination of intravascular neutrophils and not by release of marrow neutrophils. The bone marrow at 12 hours showed a mild left-shifted myeloid hyperplasia of myeloblasts and promyelocytes and a tremendous erythroid hyperplasia of intermediate and late normoblasts. The bone marrow at 24 hours showed a continued mild myeloid hyperplasia and striking erythroid hyperplasia. In conclusion, IL-6 in vivo acts as a stimulus for myelopoiesis and erythropoiesis and causes accompanying peripheral changes in the number of neutrophils, lymphocytes, and RBCs.  相似文献   
87.
88.
Plasma interleukin-1 (IL-1) activity is modulated in part through the simultaneous appearance of several inhibitors of IL-1 action, including interleukin-1 receptor antagonist (IL-1ra) and the soluble IL-1 type II receptor (IL-1RII). However, little is known concerning the plasma appearance of these inhibitors in patients following operative trauma or those with sepsis syndrome. In the present report, plasma IL-1beta, IL-1ra, and soluble IL-1RI and IL-1RII concentrations were evaluated in 118 patients with sepsis syndrome or after elective operative trauma. Plasma concentrations of IL-1ra increased significantly following elective operative repair of thoraco-abdominal and abdominal aortic aneurysms, and after bowel resection for inflammatory bowel disease, but did not increase after laparoscopic cholecystectomy. Plasma IL-1ra levels were also elevated in patients with sepsis syndrome. In contrast, soluble IL-1RII levels were only increased in patients after operative repair of thoraco-abdominal aortic aneurysms and in sepsis syndrome, whereas concentrations were unaffected by the other more modest surgical procedures. Plasma IL-1RI concentrations decreased in all postoperative patients in the first 24 hours after surgery. We conclude that both plasma IL-1ra and soluble IL-1RII concentrations often increase in sepsis and following some operative trauma. Less severe operative trauma increases the plasma concentration of only IL- 1ra, whereas both IL-1ra and soluble IL-1RII are increased in patients with sepsis syndrome or following thoraco-abdominal aneurysm repair.  相似文献   
89.
Herpesvirus-like DNA sequences (KSHV/HHV-8) have recently been described in AIDS-associated Kaposi's sarcoma (KS) lesions. Many questions remain regarding the role of this virus in KS and the therapeutic implications of this finding. In the current study, KSHV/HHV-8 DNA was detected in peripheral blood mononuclear cells (PBMCs) from human immunodeficiency virus (HIV)-infected patients with KS (34/98) more often than in HIV-infected individuals without KS (12/64, P = .03). The detection of KSHV/HHV-8 DNA did not correlate with the CD4 lymphocyte count. Five patients demonstrated KSHV/HHV-8 DNA in their PBMCs during administration of intravenous foscarnet and/or ganciclovir. The continued detection of KSHV/HHV-8 DNA in the PBMCs of patients receiving these anti-herpesvirus drugs has potential implications regarding the virus-cell relationship of KSHV/HHV-8, as well as for the value of these drugs in treating or preventing KS, but additional studies are needed.  相似文献   
90.
BACKGROUND: Several studies have demonstrated that the administration of intravenous immunoglobulin (IVIG) may be followed by the transient appearance of positive red cell antibody screens, positive direct antiglobulin tests, and, occasionally, frank hemolysis. However, little information is available regarding the possibility that IVIG could transmit neutrophil and/or platelet antibodies. STUDY DESIGN AND METHODS: Serum samples were obtained both immediately before and immediately after the administration of 12 separate lots of commercially available IVIG to bone marrow transplant patients. RESULTS: None of the patients were shown by standard granulocyte immunofluorescence testing to have acquired neutrophil antibodies. Four of the 12 postinfusion sera were positive for platelet antibodies in standard platelet suspension immunofluorescence testing, but in all four instances the corresponding preinfusion serum was positive as well. CONCLUSION: The risk of acquiring neutrophil and/or platelet antibodies after the administration of commercially available IVIG appears to be low.  相似文献   
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