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排序方式: 共有446条查询结果,搜索用时 0 毫秒
361.
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363.
Giang H.T. Au Linette Mejias Vanlila K. Swami Ari D. Brooks Wan Y. Shih Wei-Heng Shih 《Biomaterials》2014
In this study, we examined the use of CdSe aqueous quantum dots (AQDs) each conjugated to three streptavidin as a fluorescent label to image Tn antigen expression in various breast tissues via a sandwich staining procedure where the primary monoclonal anti-Tn antibody was bound to the Tn antigen on the tissue, a biotin-labeled secondary antibody was bound to the primary anti-Tn antibody, and finally the streptavidin-conjugated AQDs were bound to the biotin on the secondary antibody. We evaluated the AQD staining of Tn antigen on tissue microarrays consisting of 395 cores from 115 cases including three tumor cores and one normal-tissue core from each breast cancer case and three tumor cores from each benign case. The results indicated AQD-Tn staining was positive in more than 90% of the cells in the cancer cores but not the cells in the normal-tissue cores and the benign tumor cores. As a result, AQD-Tn staining exhibited 95% sensitivity and 90% specificity in differentiating breast cancer against normal breast tissues and benign breast conditions. These results were better than the 90% sensitivity and 80% specificity exhibited by the corresponding horse radish peroxidase (HRP) staining using the same antibodies on the same tissues and those of previous studies that used different fluorescent labels to image Tn antigen. In addition to sensitivity and specificity, the current AQD-Tn staining with a definitive threshold was quantitative. 相似文献
364.
Childhood acute myeloid leukemia (AML) has a poor prognosis with standard chemotherapy. Allogeneic bone marrow transplantation (BMT) in remission improves the outlook only for the one third of patients with sibling donors. Autologous BMT with a lower morbidity and mortality is available to all. In this study, maximum cytoreduction was achieved by intensive early chemotherapy. Final intensification, with autologous BMT was offered to all those remaining in first complete remission (CR). Patients received two induction and two consolidation courses of intensively scheduled chemotherapy. Cytoreduction was assessed on day 14 and remission was assessed after courses 2 and 4. Bone marrow was harvested after recovery from the second consolidation course or after the first maintenance course and separated on a discontinuous percoll gradient before cryopreservation. Twenty-eight of 31 consecutively enrolled patients achieved CR. Three relapsed early and, of the 25 eligible, 24 underwent autologous BMT. Twenty-three patients received high-dose melphalan and 1 received busulphan and cyclophosphamide before autologous BMT at a median of 113 days (range, 86 to 301) after initial CR. Trilineage engraftment occurred in all. Neutrophil recovery to greater than 0.5 x 10(9)/L occurred at a median of 46 days (range, 13 to 92) after autologous BMT. Platelet recovery was delayed, with a median time to achieve greater than 20 x 10(9)/L of 42 days (range, 18 to 215). With a minimum follow up of 25 months following autologous BMT only 3 children have relapsed. The 5-year event-free survival rate (EFS) from diagnosis is 68% (95% confidence interval, 46% to 90%). Five- year EFS following autologous BMT is 87% (95% confidence interval, 67% to 100%). Autologous BMT with high-dose melphalan administration after intensive chemotherapy has produced EFS equivalent to allogeneic BMT and is associated with a strikingly low relapse rate. High-dose melphalan appears to be a valuable agent for conditioning therapy in AML. 相似文献
365.
In both sickle cell (SS) anemia and beta-thalassemia (beta-thal), an increase in fetal hemoglobin (HbF) ameliorates the clinical symptoms of the underlying disease. Several pharmacologic agents have been used to elevate HbF levels in adults; however, concerns regarding adverse effects of the prevailing drugs raise an urgent need for other agents capable of stimulating HbF production. We show here that sodium phenylacetate (NaPA) and its precursor, sodium 4-phenylbutyrate (NaPB), can enhance HbF production in cultured erythroid progenitor derived from normal donors and patients with SS anemia or beta-thal, when used at pharmacologic concentrations. Treatment resulted in (1) reduced cell proliferation, (2) elevated hemoglobin (Hb) content per cell (mean cellular Hb [MCH]), and (3) an increased proportion of HbF produced, associated with elevated levels of gamma-globin mRNA. Moreover, the active phenyl-fatty acids, with NaPA as a prototype, potentiated HbF induction by other drugs of clinical interest, including hydroxyurea (HU), sodium butyrate, and 5-azacytidine (5AzaC). Efficacy could be further enhanced by introducing chlorine substituents at the phenyl ring to increase drug lipophilicity. Our findings indicate that NaPA and NaPB, both already proven safe and effective in treatment of children with urea cycle disorders, might benefit also patients with severe hemoglobinopathies. The two-phase liquid culture procedure used in this study should prove valuable in further studies exploring the mechanisms of HbF induction by these agents, and might provide an assay to predict patient response in the clinical setting. 相似文献
366.
Factor XI antigen and activity in human platelets 总被引:5,自引:1,他引:5
Washed platelets, contaminated with less than 0.20% plasma factor XI, were examined for the presence of factor XI antigen and activity. These platelets contained a factor-XI-like coagulant activity (0.67 +/- 0.11 U/10(11) platelets) that remained constant after successive washes. By means of indirect immunofluorescence, a monospecific antibody to factor XI showed specific staining of both normal platelets and platelets from patients deficient in plasma factor XI. Radiolabeled Triton extracts of washed platelets and labeled purified factor XI solutions were analyzed for factor XI antigen by Staph A immunoprecipitation analysis using antibody to purified plasma factor XI followed by SDS gel electrophoresis. On unreduced gels, the platelet material ran as a single band having an apparent molecular weight of 220,000 daltons, whereas purified plasma factor XI gave a single band at 160,000 daltons. On reduced gels, the platelet material analyzed as a single band at 52,000 daltons, whereas purified factor XI gave a single band of 80,000 daltons. Analysis of a partially purified factor XI preparation from platelets by immunoelectrophoresis revealed that the platelet preparation displayed a slightly lower cathodal electrophoretic mobility at pH 8.6 than did plasma factor XI and yet appeared to possess complete antigenic identity with plasma factor XI. These results indicate that platelets possess a form of factor XI that exists as a disulfide-linked 52,000-dalton tetramer in contrast to the plasma form that circulates as a 80,000-dalton disulfide-linked dimer. 相似文献
367.
Use of 8-methoxypsoralen and long-wavelength ultraviolet radiation for decontamination of platelet concentrates 总被引:7,自引:0,他引:7
Transmission of viral diseases through blood products remains an unsolved problem in transfusion medicine. We have developed a psoralen photochemical system for decontamination of platelet concentrates in which platelets are treated with long wavelength ultraviolet radiation (UVA, 320-400 nm) in the presence of 8-methoxypsoralen (8-MOP). Bacteria, RNA viruses, and DNA viruses ranging in genome size from 1.2 x 10(6) daltons, encompassing the size range of human pathogens, were inoculated into platelet concentrates and subjected to treatment. This system inactivated 25 to 30 logs/h of bacteria Escherichia coli or Staphylococcus aureus, 6 logs/h of bacteriophage fd, 0.9 log/h of bacteriophage R17 and 1.1 logs/h of feline leukemia virus (FeLV) in platelet concentrates maintained in standard storage bags. Platelet integrity and in vitro function before, immediately following photochemical treatment, and during prolonged storage after treatment, were evaluated by measuring: (1) extracellular pH; (2) platelet yields; (3) extracellular lactate dehydrogenase (LDH) levels; (4) platelet morphology; (5) platelet aggregation responsiveness; (6) thromboxane beta-2 (TXB-2) production; (7) dense body secretion; and (8) alpha granule secretion. These assays demonstrated that this photochemical inactivation system inactivated bacteria and viruses in platelet concentrates with minimal adverse effects on the in vitro function of platelets in comparison to untreated control concentrates maintained under current, standard blood bank conditions. 相似文献
368.
Photochemical inactivation of viruses and bacteria in platelet concentrates by use of a novel psoralen and long-wavelength ultraviolet light 总被引:15,自引:0,他引:15
L Lin ; DN Cook ; GP Wiesehahn ; R Alfonso ; B Behrman ; GD Cimino ; L Corten ; PB Damonte ; R Dikeman ; K Dupuis ; YM Fang ; CV Hanson ; JE Hearst ; CY Lin ; HF Londe ; K Metchette ; AT Nerio ; JT Pu ; AA Reames ; M Rheinschmidt ; J Tessman ; ST Isaacs ; S Wollowitz ; L Corash 《Transfusion》1997,37(4):423-435
BACKGROUND: A photochemical treatment process has been developed for the inactivation of viruses and bacteria in platelet concentrates. This process is based on the photochemical reaction of a novel psoralen, S- 59, with nucleic acids upon illumination with long-wavelength ultraviolet light (UVA, 320–400 nm). STUDY DESIGN AND METHODS: High levels of pathogens were added to single-donor platelet concentrates containing 3 to 5 × 10(11) platelets in 300 mL of 35-percent autologous plasma and 65-percent platelet additive solution. After treatment with S-59 (150 microM) and UVA (0-3 J/cm2), the infectivity of each pathogen was measured with established biologic assays. In vitro platelet function after photochemical treatment was evaluated during 7 days of storage by using a panel of 14 assays. The in vivo recovery and life span of photochemically treated platelets were evaluated after 24 hours of storage in a primate transfusion model. RESULTS: The following levels of pathogen inactivation were achieved:>10(6.7) plaque-forming units (PFU) per mL of cell-free human immunodeficiency virus (HIV),>10(6.6) PFU per mL of cell-associated HIV,>10(6.8) infectious dose (ID50) per mL of duck hepatitis B virus (a model for hepatitis B virus),>10(6.5) PFU per mL of bovine viral diarrhea virus (a model for hepatitis C virus),>10(6.6) colony-forming units of Staphylococcus epidermidis, and>10(5.6) colony-forming units of Klebsiella pneumoniae. Expression of integrated HIV was inhibited by 0.1 microM S- 59 and 1 J per cm2 of UVA. In vitro and in vivo platelet function were adequately maintained after antiviral and antibacterial treatment. CONCLUSION: Photochemical treatment of platelet concentrates offers the potential for reducing transfusion-related viral and bacterial diseases. 相似文献
369.
GP Thami † S Kaur † RS Punia ‡ AJ Kanwar† 《Journal of the European Academy of Dermatology and Venereology》2002,16(2):159-161
A 70-year-old male with a superficial granulomatous ulcer is reported. Histopathological findings were the same as those described for superficial granulomatous pyoderma, a recognized variant of classic pyoderma gangrenosum. The differences between pyoderma gangrenosum and its variant superficial granulomatous pyoderma are highlighted. 相似文献
370.
Expression of neutrophil antigens after 10 days of granulocyte-colony- stimulating factor 总被引:1,自引:0,他引:1
BACKGROUND: Granulocyte-colony-stimulating factor (G-CSF) is becoming the standard agent for mobilizing granulocytes. Most granulocyte donors are given a single dose of G-CSF, but in some cases they are given G- CSF for several days, and multiple granulocyte concentrates are collected. The administration of a single dose of G-CSF induces several changes in the expression of neutrophil antigens, but the effects of multiple daily doses of G-CSF are not known. STUDY DESIGN AND METHODS: Seven healthy people received 5 microg per kg of G-CSF for 10 days. Their expression of several neutrophil antigens before, during, and after the administration of G-CSF was analyzed through the use of flow cytometry. RESULTS: The expression of L-selectin (CD62L), Fcgamma receptor (FcgammaR) III (FcgammaRIII, CD16), and the leukocyte function antigen (CD11a) decreased throughout the course of G-CSF administration, while the expression of FgammaR I (FcgammaRI, CD64) and lipopolysaccharide-binding protein receptor (CD14) increased. The expression of FcgammaR II (FcgammaRII, CD32) also increased, but not until the fourth day of G-CSF administration. The expression of amino peptidase N (CD13), C3bi receptor (CD11b), and the neutrophil beta2 integrin unit (CD18) did not change during the administration of G-CSF, but that of both CD13 and CD18 increased 3 days after the last dose. The expression of neutrophil-specific antigen NB1 initially increased, returned to pre-G-CSF levels after 4 days, and then increased again after 10 days of G-CSF administration. CONCLUSION: Changes in the expression of several neutrophil antigens occurred throughout a 10-day course of G-CSF Most of the changes occurred after one dose, but additional changes occurred later in the 10-day course and after its completion. These changes may affect the function of G-CSF-mobilized granulocytes. 相似文献