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111.
Chorioamnionitis decreased incidence of respiratory distress syndrome by elevating fetal interleukin-6 serum concentration 总被引:2,自引:0,他引:2
Shimoya K Taniguchi T Matsuzaki N Moriyama A Murata Y Kitajima H Fujimura M Nakayama M 《Human reproduction (Oxford, England)》2000,15(10):2234-2240
Respiratory distress syndrome (RDS) of newborns is one of the most important factors determining neonatal morbidity and mortality. The interleukin-6 (IL-6) titre in cord sera of RDS-free neonates born to mothers with histological chorioamnionitis was significantly higher than that in RDS-complicated neonates without chorioamnionitis. Maternal administration of glucocorticoid suppressed the IL-6 concentrations in the cord sera of fetuses with chorioamnionitis. The fetuses without chorioamnionitis who suffered from RDS even after maternal glucocorticoid administration showed a similar IL-6 titre to that of RDS-affected neonates without chorioamnionitis. Examination of the mechanism by which IL-6 decreased the incidence of fetal RDS revealed that H441-4, a human pulmonary adenocarcinoma cell line, stimulated with recombinant (r)-IL-6 started the synthesis of mRNA and protein of pulmonary surfactant protein (SP)-A. The present study shows that IL-6 elevation in fetuses with chorioamnionitis promotes fetal lung maturation by inducing SP-A synthesis, thereby decreasing the incidence of RDS in the preterm neonates. 相似文献
112.
113.
Cloning of a truncated Babesia equi gene encoding an 82-kilodalton protein and its potential use in an enzyme-linked immunosorbent assay
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Hirata H Ikadai H Yokoyama N Xuan X Fujisaki K Suzuki N Mikami T Igarashi I 《Journal of clinical microbiology》2002,40(4):1470-1474
To isolate Babesia equi genes encoding immunodominant proteins, a cDNA expression library prepared from B. equi mRNA was immunoscreened with B. equi-infected horse serum. Eighteen positive cDNA clones were obtained, and the clone that showed the strongest immunoreactivity, designated Be82, was further characterized. The Be82 gene consisted of 1,953 bp and contained a partial open reading frame lacking the 5'-terminal sequence. As shown by Western blot analyses, immune sera from mice intraperitoneally injected with the Be82 gene product recognized the 82- and 52-kDa proteins of B. equi but not those of Babesia caballi. The glutathione S-transferase fusion protein expressed in Escherichia coli that was purified and used as the antigen in the enzyme-linked immunosorbent assay reacted specifically with B. equi-infected horse sera. These results suggest that the Be82 gene product is a potential diagnostic antigen candidate in the detection of B. equi infection in horses that will be useful both in the performance of epidemiological studies and in the granting of quarantine passes. 相似文献
114.
Yasutake N Matsuzaki T Kimura K Hashimoto S Yokokura T Yoshikai Y 《Medical microbiology and immunology》1999,188(1):9-14
The involvement of several cytokines in the antitumor effect induced by intrapleural (i.pl.) injection of heat-killed cells
of Lactobacillus casei strain Shirota (LC 9018) in mice was investigated. Injection of LC 9018 i.pl. into Meth A fibrosarcoma (Meth A)-bearing mice
not only significantly prolonged the survival of the mice, but also effectively inhibited the accumulation of malignant pleural
fluid in the thoracic cavity. In the thoracic cavity of tumor-bearing mice treated with LC 9018, we observed large amounts
of several cytokines including interleukin (IL)-1β, interferon (IFN)-γ, IL-12 and tumor necrosis factor (TNF)-α. Both anti-IFN-γ
and anti-IL-12 monoclonal antibody (mAb) treatments partially diminished the antitumor activity of LC 9018 in vivo, while
the treatment of anti-IL-1β mAb did not influence the survival of the mice. However, anti-TNF-α mAb treatment completely abolished
the antitumor effect of LC 9018 in vivo, suggesting that in this model LC 9018 has a survival-prolonging effect involving
certain cytokines. Moreover, i.pl. injection of mouse recombinant TNF-α into Meth A-bearing mice pretreated with anti-TNF-α
mAb partially restored the survival-enhancing effect of LC 9018. These results led us to conclude that TNF-α induced by i.pl.
injection of LC 9018 plays an important role in the antitumor effect of LC 9018 in vivo.
Received: 22 February 1999 相似文献
115.
Purification and Characterization of Thermostable Direct Hemolysin of Vibrio parahaemolyticus 总被引:8,自引:12,他引:8
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A thermostable direct hemolysin was purified from culture filtrates of Vibrio parahaemolyticus. The purified hemolysin gave one precipitation line with the antihemolysin antiserum on agar-gel diffusion test and a single band on polyacrylamide gel electrophoresis. The hemolysin was not inactivated by heating at 70 to 100 C for 10 min. The hemolytic activity was not enhanced by the addition of lecithin. It was demonstrated that the hemolysin was a protein with a molecular weight of approximately 118,000. Amino acid analysis revealed that 43% of total amino acids were acidic amino acids, whereas 11% were basic amino acids. 相似文献
116.
Naoki Tanaka Kensaku Ito Hiromi Kitano 《Macromolecular chemistry and physics.》1994,195(10):3369-3380
The Raman spectra of solutions of poly(N-vinyl-2-pyrrolidone) (PVP; M?w = 1 000, 10 000, 40 000 and 360 000) in D2O and dimethyl sulfoxide (DMSO) were measured at various concentrations. PVP is hydrated by D2O in a manner different from N-ethyl-2-pyrrolidone (NEP) and N-methyl-2-pyrrolidone (NMP), monomer analogues of PVP. The self-association of DMSO molecules in the solution of PVP was found to be different from that in the solution of NMP by using difference spectroscopy. These phenomena were attributed to a net-like structure of concentrated solutions of PVP. 相似文献
117.
Chikako?IkebeEmail author Masaki?Kuro-o Hiromi?Ohtani Yoshie?Kawase Tomomi?Matsui Sei-ichi?Kohno 《Chromosome research》2005,13(2):157-167
Using Giemsa staining, C-banding and Ag-NOR staining techniques, we analyzed chromosomes in adult male and female Hynobius quelpaertensis and in embryos of this species in egg sacs collected from eight localities of Cheju Island, South Korea. Chromosome pair
21 was consistently homomorphic in male specimens, while it was heteromorphic in female specimens, suggesting the occurrence
of ZZ/ZW sex chromosome constitution in this species. The W chromosome, being much larger than the Z chromosome, was of three
morphologically distinct types: WA, WB and WC. Lampbrush chromosomes examined in the oocytes of one female specimen having the WA chromosome showed that the short arm of the WA chromosome and the long arm of the Z chromosome paired closely and hence are genetically homologous. We also tried to analyze
the structural relationship among the three types of W chromosomes based on their C-banding and Ag-NOR patterns. 相似文献
118.
Toshiyuki Uryu Katsuhiro Ito Ken-Ichi Kobayashi Kei Matsuzaki 《Macromolecular chemistry and physics.》1979,180(6):1509-1519
In order to elucidate the catalytic behavior of phosphorus pentafluoride in the polymerization of anhydro sugars, 13P and 19F NMR spectra were measured on a reaction mixture of 1,6-anhydro-2,3,4-tri-O-benzyl-β-D -glucopyranose (LGTBE) and PF5 with different mole ratios in a temperature range of ?40 to ?80°C. In the 31P NMR spectrum measured at low temperatures, there was a total of 16 peaks, which consisted of a broad quintet, a septet, and a sharp quartet, being assigned to the PF4O-group, to PF, and to POF3, respectively. These fluoro compounds were also determined by the 19F NMR spectrum of the reaction mixture. The concentration of PF ions was found to correspond to that of oxonium ions, which are assumed to be actual propagating species, by determining both the concentration of PF from 19F NMR spectrum and the degree of polymerization of 2,3,4-tri-O-benzyl-α-D -glucopyranan obtained. Formation of the PF5: LGTBE complex was observed from the 31P NMR spectrum of the polymerization system at ?80°C, which exhibits a broad sextet as well as absorptions due to POF3, PF4O–, and PF. To confirm the PF5:LGTBE complex, the NMR measurement of the PF5: tetrahydropyran complex was carried out. A polymerization mechanism of LGTBE by PF5 catalyst is discussed on the basis of the NMR measurement of the polymerization system. 相似文献
119.
Negawa T Mizuno S Hahashi T Kuwata H Tomida M Hoshi H Era S Kuwata K 《The Japanese journal of physiology》2002,52(2):191-198
We characterized the visual pathways involved in the stereoscopic recognition of the random dot stereogram based on the binocular disparity employing a functional magnetic resonance imaging (fMRI). The V2, V3, V4, V5, intraparietal sulcus (IPS) and the superior temporal sulcus (STS) were significantly activated during the binocular stereopsis, but the inferotemporal gyrus (ITG) was not activated. Thus a human M pathway may be part of a network involved in the stereoscopic processing based on the binocular disparity. It is intriguing that areas 44 (Broca's area) and 45 in the left hemisphere were also active during the binocular stereopsis. However, it was reported that these regions were inactive during the monocular stereopsis. To separate the specific responses directly caused by the stereoscopic recognition process from the nonspecific ones caused by the memory load or the intention, we designed a novel frequency labeled tasks (FLT) sequence. The functional MRI using the FLT indicated that the activation of areas 44 and 45 is correlated with the stereoscopic recognition based on the binocular disparity but not with the intention artifacts, suggesting that areas 44 and 45 play an essential role in the binocular disparity. 相似文献
120.
Comparison of various bone marrow fractions in the ability to participate in vascular remodeling after mechanical injury 总被引:2,自引:0,他引:2
Sahara M Sata M Matsuzaki Y Tanaka K Morita T Hirata Y Okano H Nagai R 《Stem cells (Dayton, Ohio)》2005,23(7):874-878
In contrast to conventional assumption, recent reports propose the possibility that hematopoietic stem cells (HSCs) may have broader potential to differentiate into various cell types. Here, we tested the pluripotency of HSCs by comparing vascular lesions induced by mechanical injury after bone marrow reconstitution with total bone marrow (TBM) cells, c-Kit+ Sca-1+ Lin- (KSL) cells, or a single HSC cell (Tip-SP CD34-KSL cell, CD34- c-Kit+ Sca-1+ Lin- cell with the strongest dye-efflux activity) harboring green fluorescent protein (GFP). The lesions contained a significant number of GFP-positive cells in the TBM and KSL groups, whereas GFP-positive cells were rarely detected in the HSC group. These results suggest that transdifferentiation of a highly purified HSC seems to be a rare event, if it occurs at all, whereas bone marrow cells including the KSL fraction can give rise to vascular cells that substantially contribute to repair or lesion formation after mechanical injury. 相似文献