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81.
Among several approaches to augment the therapeutic effect of adoptive immunotherapy, we focused the antitumor synergy between transferred killer cells and host's fresh lymphocytes. Immunotherapy models using murine tumors or clinical experiments revealed that preadministration of immunostimulator such as OK-432, followed by chemotherapeutic agents such as cyclophosphamide, can induce host's non-cytotoxic fresh lymphocytes that act synergistically with cultured killer cells against autologous tumor cells. Immuno-chemo-lymphocytotherapy (a sequential treatment with OK-432, chemotherapy and adoptive immunotherapy) is useful to treat the patients with advanced cancer even if the number of transferred lymphocytes is limited.  相似文献   
82.
BACKGROUND: 17alpha-Hydroxylase/17,20-lyase deficiency is caused by a defect of P450c17 which catalyzes both 17alpha-hydroxylase and 17,20-lyase reactions in adrenal glands and gonads. RESULTS: In the present study, we analyzed the CYP17 gene in a Japanese patient with 17alpha-hydroxylase/17,20-lyase deficiency. The patient was a phenotypic girl and referred to us for right-sided inguinal hernia at the age of 4 years. Biopsy of the herniated gonad showed testicular tissue. The karyotype was 46,XY. At 6 years of age, hypertension was clearly recognized and the patient was diagnosed as having 17alpha-hydroxylase/17,20-lyase deficiency based on the clinical and laboratory findings. Analysis of the CYP17 gene revealed a compound heterozygous mutation. One mutation was an undescribed single nucleotide deletion at codon 247 in exon 4 (CTT to CT: 247delT) and the other was a missense mutation resulting in a substitution of His to Leu at codon 373 in exon 6 (CAC to CTC: H373L), which has been previously shown to abolish both 17alpha-hydroxylase and 17,20-lyase activities. The functional expression study of the 247delT mutant showed that this 247delT mutation completely eliminates both 17alpha-hydroxylase and 17,20-lyase activities. CONCLUSIONS: Together, these results indicate that the patient is a compound heterozygote for the mutation of the CYP17 gene (247delT and H373L) and that these mutations inactivate both 17alpha-hydroxylase and 17,20-lyase activities and give rise to clinically manifest 17alpha-hydroxylase/17,20-lyase deficiency.  相似文献   
83.
The objectives of this study were to investigate the fate of microorganisms by using cultivation methods as well as DNA analyses in a commercial microbiological additive (MA) in the course of the composting. Almost all the predominant species in the microbial succession during composting process determined by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) were in disagreement with those determined by the clone library method. None of the microbial species in the composting stages corresponded to the microorganisms identified in the MA either by the cultivation method or DNA analysis. The results in regard to predominant microorganisms of the MA detected from the liquid medium by the PCR-DGGE did not correspond with those detected from the MA itself and composting processes. Although no evidence was found that predominant species in the MA itself dominate in the composting process, predominant species diversity in the MA itself was markedly changed after culturing at different thermophilic temperatures. These results suggested that cultivable microorganisms in the MA did not become predominant in the composting process: however, some microorganisms that are detected from the MA itself by the DNA analysis may act effectively in the composting process.  相似文献   
84.
In the present study, we examined the role of tumor necrosis factor (TNF) in interleukin (IL)-10 production by dendritic cells (DCs) using bone-marrow derived DCs from wild type (WT) and TNF-α knockout (TNF-α−/−) mice. Toll-like receptor (TLR) stimulation induced substantial level of IL-10 production by WT DCs, but significantly low level of IL-10 production by TNF-α−/− DCs. In contrast, no significant difference was detected in IL-12 p40 production between WT and TNF-α−/− DCs. Addition of TNF-α during TLR stimulation recovered the impaired ability of TNF-α−/− DCs for IL-10 production. This recovery appeared to be associated with an activation of extracellular signal-regulated kinase, p38 mitogen-activated protein kinase, and phosphatidylinositol 3-kinase/Akt following the TNF-α addition. Blocking these kinases significantly inhibited IL-10 production by TNF-α−/− DCs stimulated with TLR ligands plus TNF-α. Thus, TNF-α may be a key molecule to regulate the balance between anti-inflammatory versus inflammatory cytokine production in DCs.  相似文献   
85.
To find novel proteins involved in radio-resistance of human cells, we searched for nuclear proteins, whose expression levels alter after X-ray irradiation in HeLa cells, using agarose fluorescent two-dimensional differential gel electrophoresis following mass spectrometry. We identified 6 proteins, whose levels were increased in nuclei 24 h after irradiation at 5 Gy, including aldolase A. Nuclear aldolase A levels increased twofold after the irradiation, however, total aldolase A levels did not change. When the expression of aldolase A was suppressed by its specific siRNA, sensitization of the suppressed cells to X-ray-induced cell death was observed. In addition, UVr-1 cells with higher aldolase A expression exhibited lower sensitivity to X-ray-induced cell death than the parental RSa cells with lower aldolase A expression. These results suggest that aldolase A may play a role in the radio-response of human cells, probably in nuclei, in addition to its glycolytic role in the cytosol.  相似文献   
86.
Starch synthase (SS) I and IIIa are the first and second largest components of total soluble SS activity, respectively, in developing japonica rice (Oryza sativa L.) endosperm. To elucidate the distinct and overlapping functions of these enzymes, double mutants were created by crossing the ss1 null mutant with the ss3a null mutant. In the F(2) generation, two opaque seed types were found to have either the ss1ss1/SS3ass3a or the SS1ss1/ss3ass3a genotype. Phenotypic analyses revealed lower SS activity in the endosperm of these lines than in those of the parent mutant lines since these seeds had different copies of SSI and SSIIIa genes in a heterozygous state. The endosperm of the two types of opaque seeds contained the unique starch with modified fine structure, round-shaped starch granules, high amylose content, and specific physicochemical properties. The seed weight was ~90% of that of the wild type. The amount of granule-bound starch synthase I (GBSSI) and the activity of ADP-glucose pyrophosphorylase (AGPase) were higher than in the wild type and parent mutant lines. The double-recessive homozygous mutant prepared from both ss1 and ss3a null mutants was considered sterile, while the mutant produced by the leaky ss1 mutant×ss3a null mutant cross was fertile. This present study strongly suggests that at least SSI or SSIIIa is required for starch biosynthesis in rice endosperm.  相似文献   
87.

Introduction

In rheumatoid arthritis (RA), synovial fluid (SF) contains a large number of neutrophils that contribute to the inflammation and destruction of the joints. The SF also contains granulocyte-macrophage colony-stimulating factor (GM-CSF), which sustains viability of neutrophils and activates their functions. Using proteomic surveillance, we here tried to elucidate the effects of GM-CSF on neutrophils.

Methods

Neutrophils stimulated by GM-CSF were divided into four subcellular fractions: cytosol, membrane/organelle, nuclei, and cytoskeleton. Then, proteins were extracted from each fraction and digested by trypsin. The produced peptides were detected using matrix-assisted laser desorption ionisation-time-of-flight mass spectrometry (MALDI-TOF MS).

Results

We detected 33 peptide peaks whose expression was upregulated by more than 2.5-fold in GM-CSF stimulated neutrophils and identified 11 proteins out of the 33 peptides using MALDI-TOF/TOF MS analysis and protein database searches. One of the identified proteins was neutrophil gelatinase-associated lipocalin (NGAL). We confirmed that the level of NGAL in SF was significantly higher in patients with RA than in those with osteoarthritis. We next addressed possible roles of the increased NGAL in RA. We analysed proteome alteration of synoviocytes from patients with RA by treatment with NGAL in vitro. We found that, out of the detected protein spots (approximately 3,600 protein spots), the intensity of 21 protein spots increased by more than 1.5-fold and the intensity of 10 protein spots decreased by less than 1 to 1.5-fold as a result of the NGAL treatment. Among the 21 increased protein spots, we identified 9 proteins including transitional endoplasmic reticulum ATPase (TERA), cathepsin D, and transglutaminase 2 (TG2), which increased to 4.8-fold, 1.5-fold and 1.6-fold, respectively. Two-dimensional electrophoresis followed by western blot analysis confirmed the upregulation of TERA by the NGAL treatment and, moreover, the western blot analysis showed that the NGAL treatment changed the protein spots caused by post-translational modification of TERA. Furthermore, NGAL cancelled out the proliferative effects of fibroblast growth factor (FGF)-2 and epidermal growth factor (EGF) on chondrocytes from a patient with RA and proliferative effect of FGF-2 on chondrosarcoma cells.

Conclusions

Our results indicate that GM-CSF contributes to the pathogenesis of RA through upregulation of NGAL in neutrophils, followed by induction of TERA, cathepsin D and TG2 in synoviocytes. NGAL and the upregulated enzymes may therefore play an important role in RA.  相似文献   
88.
Shinobu Satoh  Tadashi Fujii 《Planta》1988,175(3):364-373
A glycoprotein (GP57) was purified by ion-exchange and hydroxylapatite column chromatography from the 70%-ethanol precipitate of culture medium of non-embryogenic carrot cells (Daucus carota L.) grown with 2,4-dichlorophen-oxyacetic acid (2,4-D). Its apparent molecular mass (M r) was estimated to be 57000 by sodium dodecylsulfate-polyacrylamide gel electrophoresis and 50000 by gel filtration. GP57 contained 14% (w/w) carbohydrate; the M r of the peptide portion was estimated to be 55000 after deglycosylation by trifluoromethanesulfonic acid. GP57 is composed of two polypeptides with the same Mr and with very similar amino-acid composition but different pI values, 8.8 and 9.5. Both are rich in aspartic acid, serine and threonine, and may possess N-linked oligosaccharide chains, including fucose and xylose. A monoclonal antibody (MAb) against the purified GP57 reacted with both the pI 8.8 and the 9.5 components, as well as the deglycosylated GP57. Immunoblotting with the MAb indicated that GP57 is synthesized in and released from cultured cells which have been supplied with auxin. In immunocytochemical studies, GP57 was found in the space between the embryo and the endosperm of dry seeds, and its content decreased during germination. GP57 was also found in the endodermis and epidermis of young roots, the periderm of mature taproots, and the epidermis of petioles and young leaves.Abbreviations 2,4-D 2,4-dichlorophenoxyacetic acid - GP57 M r-57000 glycoprotein - GP65 M r-65000 glycoprotein - MAb monoclonal antibody - M r apparent molecular mass - SDS-PAGE sodium dodecylsulfate-polyacrylamide gel electrophoresis - TFMS trifluoromethanesulfonic acid  相似文献   
89.
RNA/DNA ratio is a useful and reliable indicator of the nutritional status of fish larvae and juveniles. In order to assess the nutritional status of field-caught larval Pacific bluefin tuna Thunnus orientalis (Temminck et Schlegel), starvation experiments of hatchery-reared larvae were conducted and changes in the RNA/DNA ratio of fed and starved larvae were analyzed. Starvation experiments were conducted every 3 days after first feeding. The survival rate of Pacific bluefin tuna larvae ranged 10-50% after 1 day of starved conditions and growth retardation was observed immediately. These results suggest that Pacific bluefin tuna larvae have a very low tolerance to starvation. The RNA/DNA ratios of fed larvae were approximately 2.0-4.0. On the other hand, the value of starved larvae significantly decreased to 1.0-3.0. The nutritional status of 3 cohorts of field-caught tuna larvae collected in the northwestern Pacific Ocean was examined based on the value of the RNA/DNA ratio of the 1 day starved larvae. 4.35-25.77% of the cohorts were regarded as the “starving condition”, which was negatively correlated to the ambient prey densities. These findings suggest that the nutritional condition of larval Pacific bluefin tuna was influenced by the ambient prey density, and starvation itself and starvation-induced predation could greatly contribute to mortality in the larval period of Pacific bluefin tuna.  相似文献   
90.
The egg of the ascidian Ciona savignyi is pinkish red with brownish myoplasm that contains the putative determinants responsible for differentiation of muscle cells. When dechorionated unfertilized eggs were centrifuged at moderate speed, eggs were divided into centripetal, small gray fragments and centrifugal, large red fragments. The former contained the female pronucleus and clear cytoplasm, while most of the latter was filled with yolk granules. An antibody raised against the myoplasm of C. intestinalis eggs extensively stained the cortical region of gray fragments, while the antibody stained only small regions of the red fragments. After insemination, both fragments cleaved and gave rise to partial embryos. When development of muscle and epidermal cells in the partial embryos was examined with specific antibodies, muscle development was conspicuous in gray partial embryos, while epidermal differentiation was extensive in red partial embryos. Furthermore, when expression of markers of differentiation was examined in cleavage-arrested gray and red fragments, the number of arrested gray fragments exhibiting the muscle marker was about three-fold greater than in controls. These results suggest that putative muscle determinants are concentrated into gray fragments.  相似文献   
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