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71.
S Kayashima  S Tsuru  N Hata    M Rokutanda 《Immunology》1993,80(3):471-476
Anti-listerial activity in SCID mice as well as in control C.B-17 mice was augmented by granulocyte colony-stimulating factor (G-CSF). After 1 x 10(3) colony-forming units of Listeria monocytogenes (strain EGD) were intravenously inoculated, mice were intraperitoneally injected with G-CSF at a daily dose of 500 micrograms/kg for 5 days. The numbers of viable bacteria in the liver were significantly lower in G-CSF-treated SCID and C.B-17 mice than in non-treated mice. The surface marker analyses on gamma delta T-cell receptor (TcR), Mac-1 and F4/80, and dichlorofluorescein oxidative activity, showed a possible contribution of activated neutrophils, but not gamma/delta T cells nor activated macrophages, to the augmentation of anti-listerial activity in SCID mice. This study is one of the first reports on the anti-microbial effect of G-CSF in therapeutic use.  相似文献   
72.
Honda M  Morikawa N  Hata K  Yada T  Morita S  Ueda M  Kimata K 《Biomaterials》2003,24(20):3511-3519
This study was designed to examine the adhesion, proliferation, and morphology of chondrocytes on new scaffolds; and to examine these cells histologically for the ability of the chondrocytes to maintain chondrogenic properties after subcutaneous implantation into nude mice. Both 75:25 poly (L-lactide-co-epsilon-caprolactone) (75PLC) and 50:50 poly (L-lactide-co-epsilon-capro-lactone) scaffold (50PLC) were tested as a scaffold for rat costochondral resting zone chondrocytes in comparison with a type I collagen sponge scaffold (collagen scaffold). Both of the poly (L-lactide-co-epsilon-caprolactone) scaffolds (75PLC and 50PLC) were coated with type I collagen solution and the effects of the collagen coat (hybrid-PLC) were also examined. The hybrid-75PLC bound the same number of cells as the collagen scaffold, whereas the 75PLC and the 50PLC bound 60% and 50% fewer cells than the collagen scaffold, respectively. The cell growth on the scaffolds progressed with culture time in all scaffolds. Cell morphology was assessed by scanning electron microscopy for differences in the structure of cellular interaction. Chondrocytes on every scaffold maintained a spherical shape. The hybrid-PLCs were superior to the PLCs with respect to the number of cells attached. The PLCs had an advantageous degradation characteristic in that they retained their original shape better than the collagen scaffold. Additionally, in the PLCs seeded, the cells retained their integrity 4 weeks after implantation, although the volume of collagen scaffold decreased by 50%.  相似文献   
73.
Aurora-A is a centrosomal serine-threonine kinase that regulates mitosis. Over-expression of Aurora-A has been found in a wide range of tumors and has been implicated in oncogenic transformation. However, how Aurora-A over-expression contributes to promotion of carcinogenesis remains elusive. Immunohistochemical analysis of breast tumors revealed that over-expressed Aurora-A is not restricted to the centrosomes but is also found in the cytoplasm. This over-expressed Aurora-A appeared to be phosphorylated on Thr288, which is known to be required for its enzymatic activation. In analogy to Aurora-A's role in oocyte maturation and the early embryonic cell cycle, here we investigated whether ectopically over-expressed Aurora-A can similarly stimulate polyadenylation of mRNA in human somatic cultured cells by interacting with a human ortholog of cytoplasmic polyadenylation element binding protein, h-CPEB. In vitro experiments revealed that Aurora-A binds directly to, and phosphorylates, h-CPEB. We found that polyadenylation of mRNA tails of cyclin B1 and Cdk1 was synergistically stimulated when Aurora-A and h-CPEB were over-expressed, and they were further promoted in the presence of an Aurora-A activator Ajuba. Our results suggest a function of ectopically over-expressed Aurora-A that might be relevant for carcinogenesis.  相似文献   
74.
We developed a rapid PCR method utilizing the diversity of the insertion site IS1203 for genotyping Shiga toxin-producing Escherichia coli (STEC) O157 (IS1203 PCR typing). DNA fragments digested by PvuII, which cut IS1203 at one site, were ligated with themselves and detected by PCR with outward-facing primer pairs for IS1203. To minimize nonspecific bands, nested PCR was also performed. Two fingerprinting patterns produced from the upstream or downstream regions of IS1203 were obtained within 1 or 2 days. By combining the two patterns, 79 STEC O157 isolates were classified into 39 types, which were then classified into 36 subtypes by pulsed-field gel electrophoresis (PFGE). The discriminatory power of IS1203 PCR typing (D = 0.974) is similar to that of PFGE (D = 0.981). This method can be used for rapid and simplified genotyping.  相似文献   
75.
beta(2)-Glycoprotein I (beta(2)GPI) appears to be the major antigen for antiphospholipid antibodies (aPL) in patients with antiphospholipid syndrome (APS). In early infancy, virtually all children initiate transient immune response to non-pathogenic nutritional antigens, which fails to terminate in children with atopic diseases. To examine the possibility that a prolonged immune response to beta(2)GPI could also spread to the human protein, antibodies against human beta(2)GPI (anti-beta(2)GPI) were determined in 93 randomly selected children with different allergic diseases. A high frequency (42%) of IgG anti-beta(2)GPI was found in children with atopic dermatitis (AD), but not in those with other allergic diseases. Anti-beta(2)GPI in children with AD were exclusively of the IgG1 subclass and bound to bovine beta(2)GPI as well, but not to either beta(2)GPI combined with the phospholipid cardiolipin. The epitopes were identified in domain V of beta(2)GPI and the antibody binding was abolished upon the specific proteolytic cleavage of the phospholipid-binding C-terminal loop in domain V of beta(2)GPI. These results indicated that the epitopes for anti-beta(2)GPI in children with AD most likely resided in close vicinity of the phospholipid-binding site of beta(2)GPI. The epitopic difference from anti-beta(2)GPI in APS may explain presumed non-thrombogenicity of anti-beta(2)GPI in children with AD.  相似文献   
76.
Invasive fungal infection (IFI) is a significant complication after allogeneic hematopoietic stem cell transplantation (HSCT); however, we have little information on its clinical features after reduced intensity cord blood transplantation (RICBT) for adults. We reviewed medical records of 128 patients who underwent RICBT at Toranomon Hospital between March 2002 and November 2005. Most of the patients received purine-analogbased preparative regimens. Graft-versus-host disease (GVHD) prophylaxis was a continuous infusion of either tacrolimus 0.03 mg/kg or cyclosporine 3 mg/kg. IFI was diagnosed according to the established EORTC/NIH-MSG criteria. IFI was diagnosed in 14 patients. Thirteen of the 14 had probable invasive pulmonary aspergillosis and the other had fungemia resulting from Trichosporon spp. Median onset of IFI was day 20 (range: 1-82), and no patients developed IFI after day 100. Three-year cumulative incidence of IA was 10.2%. Four of the 13 patients with invasive aspergillosis (IA) developed grade II-IV acute GVHD, and their IA was diagnosed before the onset of acute GVHD. The mortality rate of IFI was 86%. Multivariate analysis revealed that the use of prednisolone >0.2 mg/kg (relative risk 7.97, 95% confidence interval 2.24-28.4, P = .0014) was a significant risk factor for IA. This study suggests that IFI is an important cause of deaths after RICBT, and effective strategies are warranted to prevent IFI.  相似文献   
77.
We examined the cellular activity in the rostral cingulate motor area (CMAr) with respect to multiple behavioral factors that ranged from the retrieval and processing of associative visual signals to the planning and execution of instructed actions. We analyzed the neuronal activity in monkeys while they performed a behavioral task in which 2 visual instruction cues were given successively with an intervening delay. One cue instructed the location of the target to be reached; the other cue instructed which arm was to be used. After a second delay, the monkey received a motor-set cue to be prepared to initiate the motor task in accordance with instructions. Finally, after a GO signal, the monkey reached for the instructed target with the instructed arm. We found that the activity of neurons in the CMAr changed profoundly throughout the behavioral task, which suggested that the CMAr participated in each of the behavioral processing steps. However, the neuronal activity was only modestly selective for the spatial location of the visual signal. We also found that selectivity for the instructional information delivered with the signals (target location and arm use) was modest. Furthermore, during the motor-set and movement periods, few CMAr neurons exhibited selectivity for such motor parameters as the location of the target or the arm to be used. The abundance and robustness of the neuronal activity within the CMAr that reflected each step of the behavioral task and the modest selectivity of the same cells for sensorimotor parameters are strikingly different from the preponderance of selectivity that we have observed in other frontal areas. Based on these results, we propose that the CMAr participates in monitoring individual behavioral events to keep track of the progress of required behavioral tasks. On the other hand, CMAr activity during motor planning may reflect the emergence of a general intention for action.  相似文献   
78.
The prevalence of hepatitis C antibodies (anti- HCV) among multitransfused patients was studied and compared with predicted values obtained from a post-transfusion hepatitis study and from data on the prevalence of anti-HCV among blood donors. The prevalence of hepatitis B core antibodies (anti-HBc) was also studied to determine the routes of transmission of hepatitis C virus. The patients consisted of 65 dialysis patients (57 on haemodialysis and 8 on continuous ambulatory peritoneal dialysis) and 71 leukemia patients in long-term remission [49 with acute myeloid leukemia (AML) and 22 with acute lymphatic leukemia (ALL)]. The presence of anti-HCV was investigated using a second generation enzyme-linked immunosorbent assay. Reactive samples were confirmed by a second generation recombinant immunoblot assay. Anti-HBc was studied in the 65 dialysis patients and in 40 of the leukemia patients. Three (4.6%) of the 65 dialysis patients and 12 (24.5%) of the 49 AML patients were anti-HCV positive whereas all of the ALL patients were seronegative. The total number of blood units transfused to 134 patients (data on two dialysis patients were not available) was 18,148, out of which 17,575 units had been transfused prior to the initiation of anti- HCV screening of blood donors. On the basis of the anti-HCV prevalence among blood donors and the incidence of post-transfusion hepatitis, the predicted number of seropositive patients was 11 and 18, respectively. Five of the 65 dialysis patients were anti-HBc positive, compared with only one of the 40 leukemia patients. It is concluded that the anti-HCV prevalence among dialysis and leukemia patients is concordant with the risk of receiving contaminated blood products, whereas hepatitis B infection may have other routes of transmission in dialysis patients. © 1993 Wiley-Liss, Inc.  相似文献   
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