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21.
Carrier detection in hemophilia A: a cooperative international study. I. The carrier phenotype 总被引:1,自引:0,他引:1
Graham JB; Rizza CR; Chediak J; Mannucci PM; Briet E; Ljung R; Kasper CK; Essien EM; Green PP 《Blood》1986,67(6):1554-1559
Eight laboratories in six countries cooperated to clarify several issues concerning the phenotypes of heterozygous carriers of hemophilia "A." Plasma levels of factor VIII (F.VIII:C, formerly VIII:C) and von Willebrand factor (VWF:Ag, formerly VIIIR:Ag) of carriers and normal women were determined by various "in-house" methods; a single lyophilized plasma standard was used for all assays. Analysis of the collated data from 336 carriers (296 obligatory carriers and 40 sporadic carriers) and 137 normal women showed that there was no difference in the F.VIII:C levels of "paternal" carriers (women who had obtained the abnormal gene from their fathers) and "maternal" carriers. Neither was there a difference in the VWF:Ag levels of normal women and either type of carrier. Age was found to have a significant effect on both F.VIII:C and VWF:Ag, values being higher at very young and very old ages, the minima occurring in the 25- to 30-year range. ABO blood type had a striking effect. Women of types A, B, and AB (designated non- O in the study), both normals and carriers, had significantly higher levels of both factors than did women of type O. Analysis by laboratories showed that differences in mean levels of both factors between laboratories were highly significant. It was concluded that age, ABO blood type, and laboratory variation should be taken into account in carrier detection. 相似文献
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23.
Lymphokine-induced phagocytosis in angiocentric immunoproliferative lesions (AIL) and malignant lymphoma arising in AIL 总被引:1,自引:1,他引:1
A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states. 相似文献
24.
Differential effects of nitric oxide on erythroid and myeloid colony growth from CD34+ human bone marrow cells 总被引:15,自引:0,他引:15
Nitric oxide (NO) is a reactive molecule with numerous physiologic and pathophysiologic roles affecting the nervous, cardiovascular, and immune systems. In previous work, we have demonstrated that NO inhibits the growth and induces the monocytic differentiation of cells of the HL- 60 cell line. We have also demonstrated that NO inhibits the growth of acute nonlymphocytic leukemia cells freshly isolated from untreated patients and increases monocytic differentiation antigens in some. In the present work, we studied the effect of NO on the growth and differentiation of normal human bone marrow cells in vitro. Mononuclear cells isolated from human bone marrow were cultured in semisolid media and treated with the NO-donating agents sodium nitroprusside (SNP) or S- nitroso-acetyl penicillamine (SNAP) (0.25 to 1 mmol/L). Both agents decreased colony-forming unit-erythroid (CFU-E) and colony-forming unit- granulocyte macrophage (CFU-GM) formation by 34% to 100%. When CD34+ cells were examined, we noted that these cells responded to SNP and SNAP differently than did the mononuclear cells. At a concentration range of 0.25 to 1 mmol/L, SNP inhibited the growth of CFU-E by 30% to 75%. However, at the same concentration range, SNP increased the number of CFU-GM by up to 94%. At concentrations of 0.25 to 1 mmol/L, SNAP inhibited the growth of CFU-E by 33% to 100%. At a concentration of 0.25 mmol/L, SNAP did not affect CFU-GM. At higher concentrations, SNAP inhibited the growth of CFU-GM. Although SNP increased intracellular levels of cGMP in bone marrow cells, increasing cGMP in cells by addition of 8-Br-cGMP (a membrane permeable cGMP analogue) did not reproduce the observed NO effects on bone marrow colonies. These results demonstrate that NO can influence the growth and differentiation of normal human bone marrow cells. NO (generated in the bone marrow microenvironment) may play an important role modulating the growth and differentiation of bone marrow cells in vivo. 相似文献
25.
Daniel Zúiga-Núez Pablo Barrias Gloria Crdenas-Jirn M. Soledad Ureta-Zaartu Camilo Lopez-Alarcn F. Eduardo Morn Vieyra Claudio D. Borsarelli Emilio I. Alarcon Alexis Aspe 《RSC advances》2018,8(4):1927
Coumarin compounds have been described as anti-inflammatories, and chemotherapeutic agents as well as antioxidants. However, the origin of the antioxidant activity of non phenolic coumarins remains obscure. In the present report, we demonstrate that non-phenolic 7-dialkyl-aminocoumarins may also have significant antioxidant properties against free radicals derived from 2,2′-azobis(2-amidinopropane) dihydrochloride under aerobic conditions. This atypical behaviour is due to the presence of traces of very reactive hydroxycinnamic acid-type compounds. Changing functional groups at the C-3 and C-4 positions shifts the reactivity of the compounds from peroxyl to alkoxyl free radicals. Kinetic and theoretical studies based on Density Functional Theory support the formation of reactive hydroxycinnamic acid and directly link the antioxidant behaviour of the compounds to hydrogen atom transfer.Relevant antioxidant properties of non-phenolic 7-dialkyl-aminocoumarins against free radicals derived from 2,2′-azobis(2-amidinopropane) dihydrochloride under aerobic conditions have been experimentally and theoretically demonstrated. 相似文献
26.
27.
Ifosfamide and vinorelbine is an effective reinduction regimen in children with refractory/relapsed Hodgkin lymphoma,AHOD00P1: A children's oncology group report
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28.
Evolutionary relationship between the T3 chains of the T-cell receptor complex and the immunoglobulin supergene family. 总被引:14,自引:6,他引:14
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D P Gold H Clevers B Alarcon S Dunlap J Novotny A F Williams C Terhorst 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(21):7649-7653
Antigen receptors on the surface of the thymus-derived (T) lymphocytes are associated with small integral membrane proteins called the T3 (CD3) gamma, delta, epsilon, and zeta chains. After interaction of the T-cell receptor with antigen, the T3 proteins are believed to transfer an activation signal to the intracellular compartment. In previous studies, the human gamma, epsilon, and delta chains have been cloned along with the mouse delta chain, but a relationship between these sequences and known molecular families has not been established. We now report the molecular cloning and characterization of the murine T3-epsilon protein and a sequence and structural analysis of the relationships between all the T3 chains and the immunoglobulin superfamily. It is established that the T3 chains are immunoglobulin-related and a particular relationship to the neural cell adhesion molecule (N-CAM) is noted. This sequence relationship adds interest to previous findings that the T3 chains are genetically linked to N-CAM and Thy-1 antigen on band q23 of human chromosome 11. 相似文献
29.
30.
Protective immunization against inhalational anthrax: a comparison of minimally invasive delivery platforms 总被引:8,自引:0,他引:8
Mikszta JA Sullivan VJ Dean C Waterston AM Alarcon JB Dekker JP Brittingham JM Huang J Hwang CR Ferriter M Jiang G Mar K Saikh KU Stiles BG Roy CJ Ulrich RG Harvey NG 《The Journal of infectious diseases》2005,191(2):278-288
A new anthrax vaccine under clinical investigation is based on recombinant Bacillus anthracis protective antigen (rPA). Here, we investigated microneedle-based cutaneous and nasal mucosal delivery of rPA in mice and rabbits. In mice, intradermal (id) delivery achieved up to 90% seroconversion after a single dose, compared with 20% after intramuscular (im) injection. Intranasal (inl) delivery of a liquid formulation required 3 doses to achieve responses that were comparable with those achieved via the id or im routes. In rabbits, id delivery provided complete protection against aerosol challenge with anthrax spores; in addition, novel powder formulations administered inl provided complete protection, whereas a liquid formulation provided only partial protection. These results demonstrate, for the first time, that cutaneous or nasal mucosal administration of rPA provides complete protection against inhalational anthrax in rabbits. The novel vaccine/device combinations described here have the potential to improve the efficacy of rPA and other biodefense vaccines. 相似文献