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61.
Mean platelet survival and turnover were simultaneously determined with autologous 111In-labeled platelets (111In-AP) and homologous 51Cr- labeled platelets (51Cr-HP) in ten patients with chronic immune thrombocytopenic purpura (ITP). In vivo redistribution of the 111In-AP was quantitated with a scintillation camera and computer-assisted image analysis. The patients were divided into two groups: those with splenic platelet sequestration (spleen-liver 111In activity ratio greater than 1.4), and those with diffuse sequestration in the reticuloendothelial system. The latter patients had more severe ITP reflected by pronounced thrombocytopenia, decreased platelet turnover, and prominent early hepatic platelet sequestration. Mean platelet life span estimated with 51Cr-HP was consistently shorter than that of 111In-AP. Platelet turnover determined with 51Cr-HP was thus over-estimated. The difference in results with the two isotope labels was apparently due to greater in vivo elution of 51Cr. Although the limitations of the techniques should be taken into account, these findings indicate that platelet turnover is not always normal or increased in ITP, but is low in severe disease. We suggest that this may be ascribed to damage to megakaryocytes by antiplatelet antibody. The physical characteristics in 111In clearly make this radionuclide superior to 51Cr for the study of platelet kinetics in ITP. 相似文献
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MG Pacheco-Tovar E Avalos-Díaz E Vega-Memije JJ Bollain-y-Goytia E López-Robles MT Hojyo-Tomoka L Domínguez-Soto R Herrera-Esparza 《Journal of the European Academy of Dermatology and Venereology》2009,23(6):697-701
Background Pemphigus is an autoimmune disease characterized by the formation of intra-epidermal blisters. Patients develop auto-antibodies against desmoglein 1 and 3 proteins and induce acantholysis.
Objective This work addresses the issue of whether the Fas pathway mediates acantholysis. Furthermore, the possible suppliers of the Fas pathway were investigated.
Methods Seventeen biopsies of pemphigus patients were studied by haematoxylin and eosin staining, and apoptosis was defined by TUNEL. The expression of Fas, FasL and caspase 3 was studied by in situ hybridization and immunohistochemistry. Cell infiltrates were studied by immunofluorescence with monoclonal anti-CD3, CD4, CD8, CD19 and CD69.
Results All of the biopsies showed intra-epidermal blisters, acantholytic cells and inflammatory infiltrates. The blisters expressed Fas, FasL and caspase 3. Cell infiltrates were composed of CD8 and a few CD4+ CD69+ cells. Additionally, CD19+ cells were detected. Interestingly, the Fas expression was increased in acantholytic cells and perilesional keratinocytes. Incidentally, these cells exhibited apoptotic features. Interestingly, the CD8 cells expressed FasL.
Conclusion This paper presents the morphological evidence that apoptosis and acantholysis are linked. Therefore, the Fas pathway is associated with CD8 cells in pemphigus lesions.
None declared. 相似文献
Objective This work addresses the issue of whether the Fas pathway mediates acantholysis. Furthermore, the possible suppliers of the Fas pathway were investigated.
Methods Seventeen biopsies of pemphigus patients were studied by haematoxylin and eosin staining, and apoptosis was defined by TUNEL. The expression of Fas, FasL and caspase 3 was studied by in situ hybridization and immunohistochemistry. Cell infiltrates were studied by immunofluorescence with monoclonal anti-CD3, CD4, CD8, CD19 and CD69.
Results All of the biopsies showed intra-epidermal blisters, acantholytic cells and inflammatory infiltrates. The blisters expressed Fas, FasL and caspase 3. Cell infiltrates were composed of CD8 and a few CD4
Conclusion This paper presents the morphological evidence that apoptosis and acantholysis are linked. Therefore, the Fas pathway is associated with CD8 cells in pemphigus lesions.
Conflicts of interest
None declared. 相似文献
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65.
Increased expression of tissue plasminogen activator and its inhibitor and reduced fibrinolytic potential of human endothelial cells cultured in elevated glucose. 总被引:10,自引:0,他引:10
M Maiello D Boeri F Podesta E Cagliero M Vichi P Odetti L Adezati M Lorenzi 《Diabetes》1992,41(8):1009-1015
In diabetic patients, elevated plasma levels of t-PA and PAI-1 accompany impaired fibrinolysis. To identify mechanisms for these abnormalities, we examined whether vascular endothelial cells exposed to high glucose upregulate t-PA and PAI-1 production and whether ambient PA activity is decreased concomitantly. In 17 cultures of human umbilical vein endothelial cells grown to confluency in 30 mM glucose, the t-PA antigen released to the medium in 24 h was (median) 52 ng/10(6) cells (range 10-384) and the PAI-1 antigen was 872 ng/10(6) cells (range 217-2074)--both greater (P less than 0.02) than the amounts released by paired control cultures grown in 5 mM glucose--29 ng/10(6) cells (range 7.5-216) and 461 ng/10(6) cells (range 230-3215), respectively. In the presence of high glucose, the steady-state levels of t-PA and PAI-1 mRNAs were increased correspondingly (median 142 and 183% of control, respectively, P less than 0.05); high glucose per se and hypertonicity contributed to the upregulation in additive fashion. The PA activity of conditioned medium from cultures exposed to high glucose was 0.4 IU/ml (range 0.2-0.6), which was significantly lower (P less than 0.02) than the PA activity of control medium (0.5 IU/ml, range 0.2-0.9). No difference was observed when comparing the PA activities of acidified conditioned media, expected to be depleted of inhibitors. Thus, high glucose coordinately upregulates endothelial t-PA and PAI-1 expression through effects exerted at the pretranslational level and enhanced by even mild degrees of hypertonicity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
66.
Nuclear RNA sequences coding for alpha and beta globins in erythroid cells: evidence for multiple intermediate molecules 总被引:1,自引:0,他引:1
The poly (A)-containing nuclear RNA from dimethylsulfoxide-induced Friend leukemia cells was fractionated by acrylamide gel electrophoresis in denaturing conditions and analyzed for alpha and beta globin RNA sequences. The results indicate that nuclear RNA contains one species of large-size RNA (0.6 X 10(6) daltons), which is the putative precursor for beta globin mRNA only. In addition, it was shown by electrophoretic analysis that the complex of RNA molecules not resolved by sucrose gradient centrifugation (11S) comprises sequences of decreasing size (0.34, 0.28, and 0.26 X 10(6) daltons), which might be the precursors of alpha and beta globin mRNA. 相似文献
67.
Pre‐therapy inflammation and coagulation activation and long‐term CD4 count responses to the initiation of antiretroviral therapy
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68.
Riccardo Fabian Fonzar Michele Carrabba Maurizio Sedda Marco Ferrari Cecilia Goracci Alessandro Vichi 《Dental materials》2017,33(1):63-70
Objective
To compare flexural strength of CAD-CAM and heat-pressed lithium disilicate.Methods
For Pressed specimens (Group A), acrylate polymer blocks were cut with a saw in bars shape. Sprueing, investing and preheating procedures were carried out following manufacturer’s instructions. IPS e.max Press ingots (Ivoclar-Vivadent) were divided into subgroups (n = 15) according to translucency: A.1 = HT-A3; A.2 = MT-A3; A.3 = LT-A3; A.4 = MO2. Ingots were then pressed following manufacturer’s instructions. For CAD-CAM specimens (Group B) blocks of IPS e.max CAD (Ivoclar-Vivadent) were divided into subgroups: B.1 = HT-A3; B.2 = MT-A3; B.3 = LT-A3; B.4 = MO2. Specimens (n = 15) were obtained by cutting the blocks with a saw. Final crystallization was performed following manufacturer’s instructions. Both Press and CAD specimens were polished and finished with silica carbide papers of increasing grit. Final dimensions of the specimens were 4.0 ± 0.2 mm, 1.2 ± 0.2 mm, and 16.0 ± 0.2 mm. Specimens were tested using a three-point bending test. Flexural strength, Weibull modulus, and Weibull characteristic strength were calculated. Flexural strength data were statistically analyzed.Results
The overall means of Press and CAD specimens did not differ significantly. Within the Press group different translucencies were found to have similar flexural strength. Within the CAD group, statistically significant differences emerged among the tested translucencies (p < 0.001). Specifically, MT had significantly higher flexural strength than HT and MO. Also, LT exhibited significantly higher flexural strength than MO.Significance
The choice between IPS e.max Press and IPS e.max CAD formulations can be based on different criteria than flexural resistance. Within each formulation, for IPS e.max Press translucency does not affect the flexural strength while for IPS e.max CAD it is an influential factor. 相似文献69.
70.