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91.
Chronic myelogenous leukemia (CML) is a hematologic malignancy characterized by the presence of the Philadelphia (Ph) chromosome. Bcr- abl, the fusion gene associated with the Ph chromosome, expresses a p210bcr-abl protein that promotes a selective expansion of mature myeloid progenitor cells. Methylphosphonate (MP) oligodeoxynucleotides complementary to specific regions of the bcr-abl mRNA were incorporated in liposomes. We studied the effects of liposomal MP (L-MP) on the growth inhibition of CML-like cell lines. L-MP targeted to the breakpoint junctions of the bcr-abl mRNA inhibited the growth of CML cells. Fifty percent inhibition was achieved at approximately 1 mumol/L of L-MP oligonucleotide concentrations. The inhibitory effect was selective because growth inhibition was observed only with CML but not with control cell lines. Moreover, CML cell growth inhibition was dependent on the sequence of the MP oligodeoxynucleotides incorporated in the liposomes. The growth inhibition of CML cells by L-MP resulted from selective inhibition of the expression of the p210bcr-abl protein.  相似文献   
92.
93.
Galli  SJ; Arizono  N; Murakami  T; Dvorak  AM; Fox  JG 《Blood》1987,69(6):1661-1666
The normal skin and other tissues of adult mast cell-deficient WBB6F1- W/Wv or WCB6F1-Sl/Sld mice contain less than 1.0% the number of mast cells present in the corresponding tissues of the congenic normal (+/+) mice. As a result, genetically mast cell-deficient WBB6F1-W/Wv or WCB6F1-Sl/Sld mice are widely used for studies of mast cell differentiation and function. We found that mast cells developed at sites of idiopathic chronic dermatitis in WBB6F1-W/Wv mice and that the number of mast cells present in the skin of WBB6F1-W/Wv mice was proportional to the severity of the dermatitis (in ear skin, there were 33 +/- 4 mast cells/mm2 of dermis at sites of severe dermatitis v 9 +/- 3 at sites of mild dermatitis, 0.8 +/- 0.3 in skin without dermatitis, and 100 +/- 7 in the normal skin of congenic WBB6F1-+/+ mice; in back skin, the corresponding values were 2.0 +/- 0.6, 1.1 +/- 0.9, 0.025 +/- 0.025, and 26.2 +/- 3.2). The development of mast cells was a local, not systemic, consequence of the dermatitis. Thus, WBB6F1-W/Wv mice with severe dermatitis lacked mast cells in skin not showing signs of dermatitis and also in the peritoneal cavity, stomach, cecum, and tongue. Idiopathic chronic dermatitis was not associated with the local development of mast cells in WCB6F1-Sl/Sld mice, a mutant whose mast cell deficiency is due to a mechanism distinct from that of WBB6F1-W/Wv mice. These findings may have implications for understanding the nature of the mast cell deficiency in WBB6F1-W/Wv and WCB6F1-Sl/Sld mice and for the use of these mutants to analyze mast cell differentiation and function.  相似文献   
94.
Hemophilia A: carrier detection and prenatal diagnosis by DNA analysis   总被引:2,自引:0,他引:2  
In this study, we used DNA polymorphisms for carrier detection and prenatal diagnosis of hemophilia A in a large group of Italian families. The restriction fragment length polymorphisms (RFLPs) investigated were the intragenic polymorphic Bc/I site within the factor VIII gene; the extragenic multiallelic Taq I system at the St14 locus; and the extragenic Bg/II site at the DX13 locus. The factor VIII probe was informative in 30%, St14 in 82%, and DX13 in 60% of obligate carriers. The combination of factor VIII-Bc/I and St14-Taq I showed that 91% of obligate carriers were heterozygotes for one or both; with all three probes, only 4% of obligate carriers were noninformative. In families clearly segregating for hemophilia A, RFLP analysis allowed us to define the carrier status for the hemophilia A gene in all 27 women tested. RFLP analysis allowed us to exclude the carrier status in 39 of 45 female relatives of sporadic patients. The combination of RFLP analysis and biological assay of factor VIII allowed us to identify a de novo mutation in the maternal grandfather in 7 of 12 of the families with sporadic cases, for which members of three generations were available for study. Nine of 10 couples requesting prenatal diagnosis provided informative RFLP DNA pattern. Carrier status was excluded in two women, two fetuses were shown to be female, and prenatal diagnosis was carried out in five pregnancies by DNA analysis. Prenatal testing was successful in three instances and failed in two because a sufficient amount of chorionic villous DNA was not obtained for the analysis.  相似文献   
95.
This is a case series and review of the literature adding11 new cases.Coronary-cameral fistulas(CCFs)are infrequent anomalies which are in general co-incidentally found during diagnostic coronary angiography(CAG).To delineate the characteristics of congenital and acquired CCFs in adults,we performed a PubMed search for papers dealing with congenital or acquired CCFs in adults.Publications on coronary-vascular fistulas or paediatric subjects were not included.From the world literature,a total of 243 adult patients were identified who had congenital(65%)or acquired(35%)CCFs.In this review,which is part one of a two-part series on CCFs,we describe and discuss the congenital fistulas,give an overview on the published literature and report details of our own series of 11 patients with MMFs and solitary macro CCFs.Of the congenital group,56%were small or large solitary macro CCFs(cut-off 1.5mm)and 9%were coronary artery-ventricular multiple micro-fistulas(MMFs).Apical hypertrophic cardiomyopathy was reported in some of the reviewed subjects with MMFs(3/24=13%)but not was seen in our own series.Conservative medical management was generally the treatment of choice in congenital MMFs;prophylactic implantable cardioverter defibrillators(ICD)were implanted in 2/24(8%)of subjects,especially when extensive micro-fistulisations were involved.None of the patients of our own series required an ICD,as the MMFs were of limited size.Congenital or acquired CCFs in adults are infrequent anomalies having a wide spectrum of clinical presentation may varies from asymptomatic to severely devastating states requiring different treatment modalities.  相似文献   
96.
Autologous stem cell transplantation (ASCT) has been proposed as a possible treatment for severe autoimmune diseases such as rheumatoid arthritis (RA), multiple sclerosis (MS), systemic sclerosis, and systemic lupus erythematosus (SLE). To date, more than 250 patients with various autoimmune disorders have undergone an ASCT since 1996. Among them, there is a very limited number of children. This review summarizes the experience with ASCT for pediatric rheumatic diseases. Most reported cases concern juvenile idiopathic arthritis (JIA). Experience with ASCT for childhood SLE, Scleroderma, or Dermatomyositis is very limited. To date, 12 children with severe systemic or polyarticular JIA, all with progressive disease activity despite the use of corticosteroids, MTX, CsA, or Cyclophosphamide were treated in our center with ASCT. Rheumatologic follow-up at 3-month intervals up to 36 months showed a marked decrease in arthritis severity as expressed by the core-set criteria for juvenile chronic arthritis (JCA) activity. However, these children remain at risk for severe viral infections due to the prolonged lymfopenia. ASCT in this severely ill patient group induces a very significant and drug-free remission of the disease, but carries a significantly risk of developing fatal MAS.  相似文献   
97.
Farese  AM; Hunt  P; Boone  T; MacVittie  TJ 《Blood》1995,86(1):54-59
Megakaryocyte growth and development factor (MGDF) is a novel cytokine that binds to the c-mpl receptor and stimulates megakaryocyte development in vitro and in vivo. This report describes the ability of recombinant human (r-Hu) MGDF to affect megakaryocytopoiesis in normal nonhuman primates. r-HuMGDF was administered subcutaneously to normal, male rhesus monkeys once per day for 10 consecutive days at dosages of 2.5, 25, or 250 micrograms/kg of body weight. Bone marrow and peripheral blood were assayed for clonogenic activity and peripheral blood counts were monitored. Circulating platelet counts increased significantly (P < .05) for all doses within 6 days of r-HuMGDF administration and reached maximal levels between day 12 and day 14 postcytokine administration. The 2.5, 25.0, and 250.0 micrograms/kg/d doses elicited peak mean platelet counts that were 592%, 670%, and 449% of baseline, respectively. Bone marrow-derived clonogenic data showed significant increases in the concentration of megakaryocyte (MEG)- colony-forming unit (CFU) and granulocyte-erythroid-macrophage- megakaryocyte (GEMM)-CFU, whereas that of granulocyte-macrophage (GM)- CFU and burst-forming unit-erythroid (BFU-e) remained unchanged during the administration of r-HuMGDF. These data show that r-HuMGDF is a potent stimulator of thrombocytopoiesis in the normal nonhuman primate.  相似文献   
98.
99.
BACKGROUND: Several substitutes for intact, viable platelets have been used for transfusion, both to people and in animal models, with varied success. Infusible platelet membrane (IPM) is prepared from human platelets. IPM retains the glycoprotein (GP)lb receptor and has platelet factor 3 activity (procoagulant activity). However, factor V, serotonin, a cytoplasmic marker enzyme (purine nucleotide phosphorylase), GPIIb/IIIa complex, and HLA class I and II antigens are all absent in IPM. STUDY DESIGN AND METHODS: IPM is prepared from outdated platelets. The platelets were disrupted by freezing and thawing; they were washed and heated to inactivate possible viral contaminants, and then the sonicated membrane microvesicle fraction was separated and lyophilized. The hemostatic activity of IPM was measured by its ability to reduce the prolonged bleeding time in thrombocytopenic rabbits. RESULTS: Administration of IPM at a dose of 2 mg per kg results in a substantial reduction in the bleeding time. In a series of 23 experiments, a median preinjection bleeding time of 15 minutes was reduced to 6 minutes within 4 hours after IPM administration. Administration of IPM did show a mild enhancement in the thrombogenicity index, as measured in the Wessler rabbit model. This enhancement is, however, not significant, as a thrombogenicity index value of up to 0.6 is clinically acceptable. CONCLUSION: IPM may have clinical potential as a substitute for platelets in the treatment of bleeding due to thrombocytopenia.  相似文献   
100.
The use of eye-patches allows to modulate the visual information treating process. Twelve subjects with a left unilateral spatial neglect, randomly divided into three groups — non treated, treated by right eye complete patching, treated by right hemifield patching — were assessed at 1 month and 3 months after acute episode, by means of functional and neuropsychological tests. Results in the subjects treated by complete eye-patch [5]show an improvement of all the assessment parameters whatever the unilateral spatial neglect seriousness degree may be. The progression is less convincing in the patients treated by eye-patch in right hemifield. The effects of the different modalities of occultation interpreted on the basis of anatomo-physiological and psychophysiological patterns of attention, suggest the role of ocular occultation in the initial, voluntary and directed, coven attention recovery and secondary of the automatic and divided overt attention.  相似文献   
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