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61.
The reliability of the Japanese public telephone facilities to transmit electrocardiograms (e.c.g.) for computer interpretation was assessed. The International Business Machine's (IBM) e.c.g. computer program by Bonner was used. No appreciable distortion of e.c.g. was observed following repeated transmission from hospitals separated by 1000 km. Thirty-four normal and 66 abnormal e.c.g.s. were transmitted twice. Identical results were observed in 97% of normals and 92% of abnormals. Following these fundamental experiments, 1236 patients' e.c.g.s. were transmitted for computer intepretation. The study showed that 98·6% (1219 cases) were technically satisfactory and 1·4% (17 cases) were not. The 17 unsatisfactory cases were classified into ten unreceivable data formats, six inconsistent measurements and one unacceptable noise level. The authors concluded that the Japanese public telephone facilities were acceptable for the transmission of e.c.g.s. for computer interpretation.  相似文献   
62.
We investigated whether saber sheath-type tracheomalacia could be treated by the slow release of bone morphogenetic protein (BMP)-2 from a gelatin sponge. A 1 cm gap was made in the middle portion of each of 10 consecutive tracheal cartilage rings in the canine cervix (control group, n = 3), then a gelatin sponge containing 12 microg of BMP-2 solution was implanted in the gap (12 microg group, n = 3). In another group (120 microg + P group, n = 3), the implanted gelatin sponge contained 120 microg of BMP-2 solution, and the gap was covered with periosteum. All of the control dogs developed saber sheath-type tracheomalacia, whereas tracheomalacia was not observed in the 12 microg and 120 microg + P groups. In the 12 microg group, fibrous cartilage was observed at the ends of the cartilage stumps. In the 120 microg + P group, newly formed bone and cartilage were observed to form a bridge between the cartilage stumps. The regeneration of cartilage or bone induced by the slow release of BMP-2 from a gelatin sponge might be useful for treatment of tracheomalacia.  相似文献   
63.
PD-1 is a member of the immunoglobulin superfamily expressed on immune cells, including T and B cells, and is involved in the delivery of inhibitory signal upon engagement of its ligands, PD-L1 and PD-L2. While the expression profile of PD-1 has been well documented, the analysis of PD-L1 and PD-L2 distributions on a protein basis has not been carried out because of the lack of available monoclonal antibodies specific for the molecules. In this study, we established two monoclonal antibodies, 1-111A and 122, specific for murine PD-L1 and PD-L2, respectively, and examined their expression profiles. Based on flow cytometric analyses, the expression of PD-L1 was detected in a variety of lymphohematopoietic cell types, including a minor proportion of T and B cells in the spleen, majority of pre-B cells and myeloid cells in bone marrow and subsets of thymocytes, while the expression of PD-L2 was not observed in the lymphohematopoietic cells at all. Notably, a significant proportion of the most immature lineage-marker-negative and c-Kit-positive bone marrow cells containing stem cells did express PD-L1. Following mitogenic stimulation, essentially all lymphocytes expressed PD-L1. Furthermore, a variety of leukemic lines also expressed PD-L1, while none of them did PD-L2. Thus, present results demonstrate the distinct expression patterns of PD-L1 and PD-L2 with the cells of lymphohematopoietic tissues exclusively expressing the former.  相似文献   
64.
The measurement of HIV antigen levels in sera or plasma of HIV-infected individuals is critical for determining the existence of antigen or infectious virus before seroconversion and for prognosis. Pretreatment of sera or plasma of HIV carriers by heating at 70 degrees C for 10 min at an acidic pH enabled us to estimate antigens efficiently in immune complexes. This procedure will also be useful in determining antigen levels in HIV carriers more precisely.  相似文献   
65.
A purified human granulocyte colony-stimulating factor (hG-CSF) was studied for its protective effect on the induction of neutropenia and enhanced susceptibility to microbial infections in mice receiving cyclophosphamide (CPA). A severe reduction in peripheral blood neutrophils was induced 4 days after injection with 200 mg of CPA per kg although the level normalized rapidly thereafter. When mice were injected subcutaneously once a day with 2.5 micrograms of hG-CSF beginning on the day after CPA injection, the reduction was prevented markedly, even 4 days later. On the other hand, in mice receiving CPA 4 days prior to infection, a weakened resistance to intraperitoneal challenge with a strain of Pseudomonas aeruginosa was induced. This weakened resistance was dose-dependently restored to normal by four daily injections with hG-CSF. A daily dose of 1.0 microgram was required for complete restoration, although hG-CSF did not directly inhibit bacterial growth in vitro. In hG-CSF-treated mice, morphologically mature neutrophils migrated rapidly into the peritoneal cavities where bacteria were inoculated, followed by a rapid elimination of bacteria from the locality as compared with controls. In addition, the same treatment with hG-CSF was able to protect significantly against systemic infections caused by Serratia marcescens, Escherichia coli, Staphylococcus aureus, and Candida albicans. These data show the possibility that prophylactic therapy with hG-CSF may augment the resistance of immunocompromised patients to infections.  相似文献   
66.
The identification of rare monogenic forms of Parkinson's disease (PD) has provided tremendous insight into the molecular pathogenesis of this disorder. Heritable mutations in alpha-synuclein, parkin, DJ-1 and PINK1 cause familial forms of PD. In the more common sporadic form of PD, oxidative stress and derangements in mitochondrial complex-I function are considered to play a prominent role in disease pathogenesis. However, the relationship of DJ-1 with other PD-linked genes and oxidative stress has not been explored. Here, we show that pathogenic mutant forms of DJ-1 specifically but differentially associate with parkin, an E3 ubiquitin ligase. Chemical cross-linking shows that pathogenic DJ-1 mutants exhibit impairments in homo-dimer formation, suggesting that parkin may bind to monomeric DJ-1. Parkin fails to specifically ubiquitinate and enhance the degradation of L166P and M26I mutant DJ-1, but instead promotes their stability in cultured cells. The interaction of parkin with L166P DJ-1 may involve a larger protein complex that contains CHIP and Hsp70, perhaps accounting for the lack of parkin-mediated ubiquitination. Oxidative stress also promotes an interaction between DJ-1 and parkin, but this does not result in the ubiquitination or degradation of DJ-1. Parkin-mediated alterations in DJ-1 protein stability may be pathogenically relevant as DJ-1 levels are dramatically increased in the detergent-insoluble fraction from sporadic PD/DLB brains, but are reduced in the insoluble fraction from parkin-linked autosomal recessive juvenile-onset PD brains. These data potentially link DJ-1 and parkin in a common molecular pathway at multiple levels that may have important implications for understanding the pathogenesis of inherited and sporadic PD.  相似文献   
67.
Family-based linkage disequilibrium (LD) mapping has been suggested as a powerful and practical alternative to linkage analysis. We have performed a genome-wide LD survey of susceptibility loci for schizophrenia in a Japanese population. We first typed 119 schizophrenic pedigrees (357 individuals) using 444 microsatellite markers, and analyzed the data using the pedigree disequilibrium test. This analysis revealed 14 markers demonstrating significant transmission distortion. To corroborate these findings, the statistical methods were changed to the extended transmission disequilibrium test (ETDT), using 80 independent complete trios (schizophrenic proband and both parents), with 68 derived from initial pedigrees and 12 newly recruited trios. ETDT supported two markers for continued association, D11S987 on 11q13.3 (P = 0.00009) and D16S423 on 16p13.3 (P = 0.002). We scrutinized the most significant genomic locus on 11q11-13 by adding 26 new markers for analysis. Results of three-marker haplotype analysis in the region showed evidence of association with schizophrenia (most significant haplotype P = 0.0005, global P = 0.022). Although the present study may have missed other potential genomic intervals because of the sparse mapping density, we hope that it has identified promising anchor points for further studies to identify risk-conferring genes for schizophrenia in the Japanese population. In addition, we provide useful information on genomic LD structures in Japanese populations, which can be used for LD mapping of complex diseases.  相似文献   
68.
We developed a novel technique to improve tendon-bone attachment by hybridizing calcium phosphate (CaP) with tendons using an alternate soaking process. We characterized the deposited CaP on or in tendons and determined the healing process of anterior cruciate ligament (ACL) grafts by implanting CaP-hybridized free tendons in bone tunnels intra-articularly. Tendons to be implanted were alternately soaked 10 times in a Ca-containing solution and a PO(4)-containing solution for 30 s each. Treated tendons had ash contents threefold that of untreated tendons. Low-crystallinity apatite was found on or in treated tendons. In animal experiments, the CaP-hybridized tendon exhibited osteoclasts at the tendon-bone interface at 5 days after operation. At 2 weeks after operation, there were more osteoclasts and osteoblasts around the tendon than at 5 days after operation. Directly bonded areas were partially found between the implanted tendon and newly formed bone. The formation of a cartilage layer was partially apparent at 3 weeks after operation. The newly formed bone was observed almost around the tendon. We conclude that CaP-hybridized tendons clearly enhance the healing process of ACL grafts at the tendon-bone interface and regenerate a direct insertion-like formation of tendons similar to a normal healthy ACL insertion within 3 weeks after operation.  相似文献   
69.
Otitis media with effusion (OME) is one of the most common ear diseases. Bacterial endotoxins and several inflammatory cytokines appear to be involved in the pathogenesis of OME in children; however, little is known of the immunological aspects of the onset of OME in adults. We sought to determine the presence of macrophage migration inhibitory factor (MIF) as well as interleukin 1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), RANTES (regulated upon activation, normal T-cell expressed and presumably secreted), and endotoxin in middle ear effusions (MEEs) from adult patients with OME. In addition, the levels of MIF in MEEs from adults and children were compared. MEE was obtained from 95 adults and 11 children. The levels of MIF, IL-1beta, TNF-alpha, and RANTES were determined by enzyme-linked immunosorbent assay, and the concentrations of endotoxin and total protein were determined by the Endospec assay and bicinchoninic acid assay, respectively. MIF was detected in 97.9% of the MEEs from adults, while endotoxin, IL-1beta, TNF-alpha, and RANTES were detected in 96.8, 12.6, 5.3, and 43.9%, respectively. In addition, the level of MIF was significantly higher than those of endotoxin, IL-1beta, and TNF-alpha. A positive correlation between the levels of MIF and endotoxin was observed. MIF and endotoxin were detected in 81.8 and 72.7%, respectively, of the MEEs from the children. The level of MIF was significantly higher in the children, and conversely that of endotoxin was significantly higher in the adults. These results suggest that the interaction between MIF and endotoxin may promote fluid collection in the middle ear, particularly in adults.  相似文献   
70.
Microanatomical localization of PD-1 in human tonsils   总被引:3,自引:0,他引:3  
PD-1 is an immunoinhibitory receptor, which belongs structurally to the CD28 family. PD-1-deficient mice show breakdown of peripheral tolerance and manifest multiple autoimmune symptoms. We previously described expression of PD-1 on activated T and B lymphocytes and myeloid cells. However, little is known about the microanatomical distribution of PD-1 in lymphoid organs. In this study, we performed immunohistochemistry using monoclonal antibodies against human PD-1. In human tonsils, PD-1 was expressed on most of T cells and a small subset of centrocytes in the light zone of germinal centers (GCs), where clonal selection of centrocytes takes place. These results suggest that PD-1 may play an important role in GC reaction.  相似文献   
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