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451.
Human hematopoietic survival and stem cell growth factor (SCGF), derived from the KPB-M15 myeloid cells, is a heat- and pH-stable protein. Chemical modification with various denaturing agents and proteolytic enzymes abrogated SCGF activity. The granulocyte-macrophage colony-potentiating and erythroid burst-promoting activities of SCGF were proportional to the density of the bone marrow (BM) cells cultured, the optimal BM cell density for delta granulocyte- and delta burst-promoting activities being 5 to 10 X 10(5)/ml. These data could be important in enabling the use of SCGF to induce proliferation of human hematopoietic stem cells in vitro. 相似文献
452.
Ai Minamidate Michio Onizawa Chikako Saito Rie Hikichi Tomoaki Mochimaru Mai Murakami Chiharu Sakuma Takehito Asakawa Yuichi Hiraoka Shigeru Oshima Takashi Nagaishi Kiichiro Tsuchiya Hiromasa Ohira Ryuichi Okamoto Mamoru Watanabe 《Biochemistry and Biophysics Reports》2021
Ikarugamycin (IK) is an antibiotic which has been reported to have a variety of functions, such as inhibition of clathrin-mediated endocytosis (CME), anti-tumor effects and regulation of the immune system. Whether IK influences cytokine production is poorly understood. We have investigated the relationship between IK and production of tumor necrosis factor-α (TNF). TNF plays a pivotal role in pathogenesis of many diseases. Although the dynamics of soluble TNF (sTNF) has been widely explored so far, the functions of the membrane form of TNF (mTNF) have not been fully elucidated. We demonstrated that IK increases the amount of mTNF and prolongs the duration of TNF expression. This effect is unrelated to the shedding activity of disintegrin and metalloproteinase domain-containing protein 17 (ADAM 17). Our results revealed that there is a mechanism to terminate inflammation at the cellular level which IK dysregulates. Furthermore, IK can be a tool to study TNF signaling due to its effect of increasing mTNF expression. 相似文献
453.
A variety of biologic activities on human hematopoietic stem cells were detected in 12-O-tetradecanoylphorbol-13-acetate-stimulated leukocyte-conditioned medium (TPA-LCM). Partial purification of TPA-LCM demonstrated the presence of human-active granulocyte-macrophage colony-stimulating factor (GM-CSF; Mr 50-70Kd), macrophage-CSF (M-CSF; Mr greater than 100Kd) and possibly a third protein (Mr 24-26Kd) supporting survival and growth of hematopoietic stem cells in vitro. Activities investigated included GM-colony and erythroid burst-potentiation, burst-promoting activity (BPA) and delta granulocyte and delta burst-promoting activities (delta GPA and delta BPA). 相似文献
454.
Jerry W. Hupp Paul L. Flint John M. Pearce Yusuke Shigeta Tetsuo Shimada Emiko N. Hiraoka Hiroyoshi Higuchi 《Journal of Field Ornithology》2012,83(2):141-153
ABSTRACT From 2006 to 2009, we marked 198 Northern Pintails (Anas acuta) with satellite transmitters on their wintering areas in Japan to study their migration routes and habitat use in spring staging areas. We hypothesized that the distribution of pintails during spring staging was influenced by patterns of land use and expected that the most frequently used areas would have more agricultural habitat than lesser‐used areas. We obtained 3031 daily locations from 163 migrant pintails marked with satellite transmitters and identified 524 stopover sites. Based on a fixed kernel home range analysis of stopover utilization distribution (UD), core staging areas (areas within the 50% UD) were identified in northern Honshu and western Hokkaido, and were used by 71% of marked pintails. Core staging areas had a greater proportion of rice fields than peripheral (51–95% UD) and rarely used (outside the 95% UD) staging areas. Stopover sites also contained more rice fields and other agricultural land than were available at regional scales, indicating that pintails selected rice and other agricultural habitats at regional and local scales. Pintails remained at spring staging areas an average of 51 d. Prolonged staging in agricultural habitats of northern Japan was likely necessary for pintails to prepare for transoceanic migration to Arctic nesting areas in eastern Russia. 相似文献
455.
A New Operation for Producing Disease-Suppressive Compost from Grass Clippings 总被引:3,自引:0,他引:3 下载免费PDF全文
This study evaluated the use of grass clippings discharged from golf courses as the raw material for production of a suppressive compost to control Rhizoctonia large-patch disease in mascarene grass. Bacillus subtilis N4, a mesophilic bacterium with suppressive effects on the pathogenic fungus Rhizoctonia solani AG2-2, was used as an inoculum in a procedure developed with the aim of controlling composting temperatures and inoculation timing. The population density of mesophilic bacteria in the raw material was reduced to around 5 log10 CFU/g (dry weight) of composting material in the self-heating reaction at the initial stage of composting by maintaining a temperature of 80°C for 1 day. The inoculum was applied immediately, and the composting material was maintained at 40°C for 3 days. This served both to highly concentrate the suppressive bacterium and to achieve sporulation. The temperature was then raised to 60°C and maintained, enabling hygienic, high-speed composting while maintaining the population density of the suppressive bacterium as high as 8 log10 CFU/g (dry weight) in the compost. The suppressiveness of compost made in this way was confirmed in a turf grass disease prevention assay. 相似文献
456.
M Abe M Hiraoka 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1985,47(4):347-359
Clinical researches in hyperthermia have recently expanded rapidly with the increase in our knowledge of the biological effects of heat on experimental systems. This article provides background information on the biological rationale and current status of technologies concerning thermometry and heating equipment for the application of hyperthermia to human cancer treatment. Much data has been accumulated recently in hyperthermia treatment with and without radiation to superficial tumours which are refractory to conventional treatments. In this paper the treatment results published recently have been surveyed. The complete responses of tumours treated by heat alone are in the range of 15 per cent as opposed to approximately 60 per cent for the combination of heat plus radiation. Clinical results so far published have demonstrated that local control is consistently better in the lesions treated with radiation plus heat than with radiation alone. The morbidity related to heat therapy is within tolerable limits. Several articles on the clinical results of deep-seated tumours treated by hyperthermia are reviewed. Problems to be solved in the application of heat to cancer therapy are discussed. 相似文献
457.
T Murakami K Hiraoka T Mikami T Matsumoto S Katagiri M Suzuki 《Microbiology and immunology》1991,35(3):223-234
A serological typing scheme of Bacillus cereus has been developed by immunochemical analyses of flagellar antigen using an agglutination method. Enzyme-linked immunosorbent assay (ELISA) for the classification of flagellar serotype of Bacillus cereus had greater sensitivity. 10-500 times, than that of agglutination method. The specificity of flagellar antigen and antibody was determined by immunogold electron microscopy and ELISA inhibition assay. Application of ELISA is useful for the detection of the small amounts and many kinds of antigen-antibody reactions. 相似文献
458.
M Shiozawa Y Hiraoka K Yasuda T Imamura D Sakamuro N Taniguchi M Yamazoe H Yoshikawa 《Gene》1990,87(2):299-303
We have determined expression of human GGT gene encoding gamma-glutamyl transpeptidase (GGT) during fetal development of liver using the Northern-blot analysis with a cloned human GGT cDNA and immunohistochemistry with a monoclonal antibody. GGT mRNA could be detected as early as the 12th week of gestation. It then increased gradually to a peak of approx. threefold the amount at week 12, at week 40, just before birth. The size of the mRNA in the fetal liver was 2.7 kb and mRNA of the same size was detected both in the human fetal kidney and human hepatocellular carcinoma as well as normal adult liver. Immunohistochemical analyses show that GGT increased as the fetal liver developed in parallel with the increase in mRNA. Histochemically, GGT was shown to be located in the wall of bile canaliculi when synthesis was low in early development, but to be distributed, in addition, all over the cell membrane of the fetal hepatocytes when synthesis was high at the later stage of development. 相似文献
459.
A simple, specific, and sensitive assay procedure for cardiolipin synthase of Escherichia coli has been developed. This measures the radioactivity of glycerol formed from phosphatidyl [2-3H]glycerol and is mainly based on the findings that 400 mM phosphate and 0.015% Triton X-100 markedly activate the enzyme. Cardiolipin synthase was amplified 760-fold upon induction with isopropyl beta-D-thiogalactoside in cells harboring a pBR322 derivative in which the cls gene encoding this enzyme was preceded by the tac promoter. Under these conditions, cardiolipin content increased, membrane potential decreased, spheroplasts became fragile, cells lost viability, and inducer-resistant mutants appeared at a high frequency. The amplification enabled the isolation of an enzyme preparation with a specific activity approximately 10,000-times higher than that of wild-type whole cell lysate. This purification was simply achieved by extraction of the crude membrane fraction with Triton X-100 and a single phosphocellulose column chromatography. This preparation, together with the crude envelope fraction, was used to characterize the basic properties of E. coli cardiolipin synthase, some of which were utilized in setting up the assay conditions. 相似文献
460.
Shoot cultures ofAtractylodes lancea DC. (Compositae) have been established by inoculating the flower bud on Linsmaier-Skoog's medium supplemented with 10−5 M naphthaleneacetic acid and 10−5 M 6-benzyl-aminopurine. Shoots were multiplied on a medium containing 10−6 M 6-benzylaminopurine. Propagated shoots rooted on a medium devoid of any plant growth regulators were transferred to potting
soil and finally to the field. 相似文献