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11.
Makoto Suematsu Shigenari Houzawa Soichiro Miura Hiroshi Nagata Tetsuji Kitahora Tetsuo Morishita Chikara Oshio Masaharu Tsuchiya 《Luminescence》1989,4(1):531-534
Reaction difference of oxyradical generation and luminol-dependent photoemission of zymosan- and phorbol ester-treated neutrophils were investigated using a conventional photomultiplier and ultrasensitive photonic imaging technique. Zymosan-treated cells released a concentrated photonic burst corresponding to the cellular distribution. In contrast, phorbol ester-treated cells produced a negligible level of photoemission, and the additional application of Ca2+ ionophore enhanced the photonic burst, which was gradually spread out into extracellular space. Serine protease inhibitors did not attenuate PMA-induced chemiluminescence but did attenuate zymosan-induced chemiluminescence. This suggests the involvement of serine protease in the respiratory burst of phagocytizing neutrophils. 相似文献
12.
A Nakai C Hirayama K Ohtsuka K Hirayoshi K Nagata 《Journal of cellular physiology》1990,143(3):577-589
Using affinity chromatography on ATP-agarose, we have identified a major ATP-binding protein in Nonidet P-40 extracts of avian and mammalian cells labeled with [35S]methionine. After washing ATP-agarose beads with high-ionic-strength buffer (0.4 M NaCl), the 37-kD protein was shown to be one of the major ATP-binding proteins while p72 and grp78, which are members of the hsp70 family, also bound to ATP-agarose. This protein consisted of several spots on two-dimensional gel electrophoresis. The isoelectric point of the most basic spot was approximately 9.2 in chick embryo fibroblasts, whereas it was about 8.8 in mouse 3T3 cells. The identities of these proteins in mouse and chick cells were confirmed by peptide mapping. After heat-shock treatment of BALB/3T3 cells, the major heat-shock protein, hsp70, was shown to be induced very rapidly after heat shock and was recovered in the ATP-binding fraction. Besides hsp70, a 37-kD protein was also found to be induced by heat shock. This protein was drastically induced by treating the cells with alpha,alpha'-dipyridyl, an iron chelating reagent, but not with sodium arsenite, calcium ionophore, or tunicamycin. The synthesis and the total amount of this ATP-binding protein increased in mouse 3T3 cells transformed by simian virus 40, methylcholanthrene, or activated c-Ha-ras oncogene compared to their normal counterparts. The incorporation of [32P]orthophosphate was not detected in either normal or transformed cells. These studies established that a major ATP-binding protein of Mr = 37,000 is a heat-inducible protein and that the synthesis of this protein is regulated by malignant transformation. 相似文献
13.
14.
Nucleotide sequence of the gene for cholesterol oxidase from a Streptomyces sp. 总被引:9,自引:3,他引:6
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The nucleotide sequence of a 2.1-kilobase-pair fragment containing the Streptomyces choA gene, which codes a secreted cholesterol oxidase, was determined. A single open reading frame encodes a mature cholesterol oxidase of 504 amino acids, with a calculated Mr of 54,913. The leader peptides extend over 42 amino acids and have the characteristics of a signal sequence, including basic amino acids near the amino terminus and a hydrophobic core near the signal cleavage site. Analyses of the total amino acid composition and amino acid sequencing of the first 21 amino acids from the N terminus of the purified extracellular enzyme agree with the values deduced from nucleotide sequencing data. 相似文献
15.
EDTA-insoluble organic structures of the hypercalcified peritubular matrix (PM) in horse dentine were observed by scanning electron microscopy. The PM was enveloped in double cylindrical structures composed of fibrillar sheaths in the inner and outer peripheries. Between the outer fibrillar sheath and intrinsic fibrils of the intertubular matrix, a calcified cementing membrane existed. Within the PM, warped cone-shaped structures of fibrillar sheaths, overlapping at intervals of 4-6 microns and semiconcentrically surrounding the dentinal tubule, extended from the inner fibrillar towards the outer fibrillar sheath. The cone-shaped fibrillar sheaths following the inner and outer fibrillar sheaths were identified as the incremental lines of the PM. Most of these fibrils may be collagen although it could not be confirmed, whereas non-collagenous organic materials in the lateral branches of the dentinal tubule are radially arranged in the PM. These EDTA-insoluble structures were three-dimensionally illustrated using an image-analysing system. 相似文献
16.
S. Yoshikawa Y. Togawa N. Mitsui K. Chikara G. Taguchi M. Shimosaka M. Okazaki 《Biotechnology letters》1996,18(6):655-658
Summary A temperature-sensitive osmophilic mutant of Zygosaccharomyces rouxii, OS15, was isolated, which required high salt or sugar concentration for growth above 30°C. Cell viability at 35°C in the presence of NaCl was higher than in the absence of NaCl, and a survival ratio of the mutant cells after incubation at 55°C was also higher in the presence of NaCl than NaCl-free condition. Furthermore, resistance to UV light, hygromycin B and geneticin was improved in the presence of NaCl. There was no difference between the parent and the mutant in fatty acid saturation and microscopic cell shape under NaCl condition. 相似文献
17.
It has been shown that mammalian neurogenesis is partly controlled by multiple basic helix–loop–helix (bHLH) genes, as inDrosophila.Recently, mouse homologs ofDrosophila atonal,a proneural gene encoding a bHLH protein required for chordotonal organ and photoreceptor development, have been characterized to obtain further insights into the molecular nature of mammalian neurogenesis. Here, to assess their potential involvement in genetic neural disorders, we have determined genetic map positions for four mouseatonal-related genes,Atoh1, Atoh2, Atoh3,andNdrf,which encode MATH-1, MATH-2, MATH-3, and NDRF, respectively. Interspecific backcross analysis indicated thatAtoh1andAtoh2were located in separate positions of Chr 6 and thatAtoh3andNdrfwere mapped to Chr 10 and Chr 11, respectively. Thus, these structurally related genes are located separately on multiple chromosomes. 相似文献
18.
The human gene encoding the mutual signal-transducing subunit (-chain) of granulocyte-macrophage colony-stimulating factor, interleukin-3, and interleukin-5 receptor complexes has been mapped to chromosome 22q13.1 by the fluorescence in situ hybridization method. 相似文献
19.
S. Takai M. Kasama K. Yamada N. Kai N. Hirayama H. Namiki T. Taniyama 《Human genetics》1994,93(1):13-15
The human FcRI gene encodes for a highaffinity Fc receptor that plays pivotal roles in the immune response. We have used fluorescence in situ hybridization analysis to localize the FcRI gene to human chromosome 1. The human FcRI (CD64) gene has been assigned to human chromosome 1q21.2-q21.3 using R-banded human (pro)metaphase chromosomes. 相似文献
20.
Hideaki Sato Hideki Hirayama Takeshi Yamamoto Yoshimasa Lchio Fumiaki Ishizawa Michinao Mizugaki 《Luminescence》1994,9(2):73-77
The purpose of the study was to evaluate the quality of Toki-shakuyaku-san extract granules (TJ-23) using chemiluminescence (CL). A linear relationship was obtained between the log value of the CL of TJ-23 and the reaction temperature. An excellent correlation (r= 0.999) was found between the slope of this curve (ΔA) and the colour intensity due to the browning reaction occurring at the early stage of the Maillard reaction. 相似文献