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141.
In rat cerebellum the major portion of guanylate cyclase was found to be particulate-bound. The properties of particulate and supernatant guanylate cyclases from the cerebellum were comparatively examined. Both enzymes required the same optimal concentration of Mn2+ and were stimulated by Ca2+ in the presence of a low concentration of Mn2+. But dispersion of the particulate enzyme with Triton X-100 altered the Mn2+ concentration producing maximum activity and the inhibitory effect of Ca2+. The subcellular distributions of guanylate and adenylate cyclases were also studied in rat cerebellum. The major portions of the two cyclases were found in the mitochondrial fraction. The submitochondrial fractions separated by sucrose gradient showed that the major activities of both cyclases were concentrated in the fraction containing mainly nerve ending particles. 相似文献
142.
Dr. Shuichi Ueda Toshikuni Tanabe Norihiko Ihara Yutaka Sano 《Cell and tissue research》1989,256(3):457-463
Summary Pieces of fetal midbrain raphe containing serotonergic and dopaminergic neurons were transplanted into the leptomeningeal tissue (see Fig. 3) of adult host rats that had previously been denervated by treatment with 5,6-dihydroxytryptamine. One, 2 and 5 months after transplantation, the rate of neuronal survival in the grafted tissue and the extent of axonal outgrowth into the host brain were studied by use of serotonin and tyrosine hydroxylase (TH) immunohistochemistry. The survival rate of the grafts in the 1-month group was approximately 70%. Neurons containing either serotonin or catecholamine were demonstrated by means of immunocytochemical procedures in the grafts. Two and 5 months after transplantation, serotonin-immunoreactive nerve fibers were densely distributed throughout the graft tissue, while TH-immunoreactive fiber elements were restricted to an area near the somata of TH-positive neurons. Numerous serotonin-immunoreactive fibers derived from the transplant were found in the leptomeningeal tissue surrounding the graft, on the wall of neighboring blood vessels, and also in the adjacent parenchyma of the host brain. Outgrowing TH-immunoreactive nerve fibers were not observed in the host brain, although such elements occurred in the leptomeningeal tissue and the wall of the larger blood vessels. These results suggest that the serotonergic and catecholaminergic (dopaminergic) neurons located in transplants of the raphe nuclei show different patterns when reinnervating the host tissue. 相似文献
143.
Osamu Hiroshima Yoshihisa Sano Teruaki Yuzuriha Chiyuki Yamato Akira Saito Naomichi Okamura† Yasuo Uchiyama† Sadao Kimura † Katsutoshi Goto 《Journal of neurochemistry》1988,50(2):480-485
The binding site for calcitonin gene-related peptide (CGRP) was solubilized with 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS) in an active form from porcine spinal cord. 125I-labeled human alpha-CGRP (125I-CGRP) binding to the solubilized protein was determined by filtration using a GF/B glass filter. The maximal binding activity (approximately 60% of the crude membrane fraction) was obtained with 5 mM CHAPS. 125I-CGRP binding to the solubilized protein was of high affinity, saturability, and high specificity, having KD and Bmax values of 3.69 pM and 338 fmol/mg of protein, respectively. The binding activity was eluted in a single peak with a molecular mass of 400,000 daltons by gel filtration on TSK gel G4000SW. These results suggest that the solubilized protein may be responsible for the specific binding site. 相似文献
144.
Tsunenori Nozawa Jeffrey T. Trost Taisei Fukada Masahiro Hatano James D. McManus Robert E. Blankenship 《BBA》1987,894(3):468-476
Reaction centers were purified from the thermophilic purple sulfur photosynthetic bacterium Chromatium tepidum. The reaction center consists of four polypeptides L, M, H and C, whose apparent molecular masses were determined to be 25, 30, 34 and 44 kDa, respectively, by polyacrylamide gel electrophoresis. The heaviest peptide corresponds to tightly bound cytochrome. The tightly bound cytochrome c contains two types of heme, high-potential c-556 and low-potential c-553. The low-potential heme is able to be photooxidized at 77 K. The reaction center exhibits laser-flash-induced absorption changes and circular dichroism spectra similar to those observed in other purple photosynthetic bacteria. Whole cells contain both ubiquinone and menaquinone. Reaction centers contain only a single active quinone; chemical analysis showed this to be menaquinone. Reaction center complexes without the tightly bound cytochrome were also prepared. The near-infrared pigment absorption bands are red-shifted in reaction centers with cytochrome compared to those without cytochrome. 相似文献
145.
Satoshi Osada Satoshi Sano Mariko Ueyama Yoshiro Chuman Hiroaki Kodama Kazuyasu Sakaguchi 《Bioorganic & medicinal chemistry》2010,18(2):605-611
Inhibitors of histone deacetylases (HDAC) are emerging as a promising class of anti-cancer agents. The mercaptoacetoamide-based inhibitors are reported to be less toxic than hydroxamate and are worthy of further consideration. Therefore, we have designed a series of analogs as potential inhibitors of HDACs, in which the mercaptoacetamide group was replaced by (mercaptomethyl)fluoroalkene, and their HDAC inhibitory activity was evaluated. Subnanomolar inhibition was observed for all synthetic compounds. 相似文献
146.
147.
Induction of antibacterial activity in larvae of the blowfly Lucilia sericata by an infected environment 总被引:1,自引:0,他引:1
Kawabata T Mitsui H Yokota K Ishino K Oguma K Sano S 《Medical and veterinary entomology》2010,24(4):375-381
Maggot debridement therapy (MDT) is a method for the treatment of intractable, infected and necrotic wounds. In MDT, sterile larvae of Lucilia sericata Meigen (Diptera: Calliphoridae) are applied to infected wounds, where they exert antibacterial effects. Once the larvae are placed in the wound, they are no longer germ-free. This study analysed the influence of infected environments on larval antibacterial activities. Sterile larvae were mixed in a test tube containing a bacterial suspension of Staphylococcus aureus or Pseudomonas aeruginosa, transferred to liver puree agar, and incubated at 25 °C for set periods. To collect the larval extracts, the incubated larvae were transferred to a test tube containing phosphate buffered saline (PBS), cut into multiple pieces with scissors, and centrifuged. The supernatant was used to test antibacterial activities. The results showed that infected larvae had better antibacterial capacities than sterile larvae. Antibacterial activities were induced by pretreatment with a single bacterial species, S. aureus or P. aeruginosa, within 24 h and 12 h, respectively, and disappeared after 36 h. The activities were effective against S. aureus, but not against P. aeruginosa. This natural infection model is very similar to the clinical wound context in MDT and will be a powerful tool with which to study the antibacterial activities of L. sericata larvae in MDT. 相似文献
148.
R. H. F. Vivan P. C. Leonello L. A. Nagashima M. S. Kaminami F. S. M. Tristão A. Sano M. A. Ono C. V. Béjar E. N. Itano 《Mycopathologia》2010,169(3):151-157
Histoplasma capsulatum var. capsulatum is a thermally dimorphic fungus that causes histoplasmosis. Fungal hemagglutination activity and cases of reactive hemophagocytic
syndrome (RHS) have been reported in the disseminated form of disease. In the present study, soluble components of H. capsulatum var. capsulatum have been investigated for hemagglutinin activity and the capacity to induce hemophagocytosis in the mouse system. To analyze
hemagglutinating activity, mouse red blood cells (RBC) (1% v/v in PBS) were incubated (37°C, 1 h) with cell-free antigen (CFAg)
from H. capsulatum var. capsulatum (isolate IMT/HC128) (RBC-CFAg) or previously heated CFAg (56°C, 30 min) (RBC-hCFAg) or as control with PBS (RBC-PBS). Hemophagocytosis
was analyzed by incubating BALB/c mouse peritoneal phagocytic cells (5 × 106 cells) with syngeneic RBC, sensitized or not with CFAg. In addition, mouse polyclonal antibodies were raised against syngeneic
RBC-CFAg (anti-RBC-CFAg) and used to analyze CFAg chromatographic fractions (Sephadex G75/120) by immunoenzymatic assay (ELISA).
Hemagglutinin activity was observed with RBC-CFAg, but not with RBC-hCFAg or RBC. Also, hemophagocytosis was observed with
RBC-CFAg, but not with RBC. The anti-RBC-CFAg antibodies reacted with CFAg fractions corresponding to a molecular mass (MM)
higher than 150 kDa. In conclusion, the yeast form of H. capsulatum var. capsulatum releases thermolabile soluble components with hemagglutinin activity and it has been demonstrated for the first time that
soluble components of the same fungus induce syngeneic hemophagocytosis in the in vitro mouse system. Also, indirect analysis
with antibodies suggests that high-MM components (>150 kDa) are responsible for the interaction with RBC. 相似文献
149.
The largest genus of the Eriocaulaceae, Paepalanthus, presents many taxonomic problems. Some of these were identified during studies of Eriocaulaceae from the flora of S?o Paulo
State and Caparaó National Park. Here, we propose changes in nomenclature as a solution to such issues, based on type collections,
recent collections and field observations. These changes are in agreement with the taxonomic species concept, and the rules
established by the International Code of Botanical Nomenclature. We define six lectotypes: P. gneissicola, P. caparoensis, P. caldensis, P. lundii, P. oerstedianus and P. striatus, and six synonyms: P. gneissicola = P. acantholimon, P. loefgrenianus = P. aequalis, P. multicostatus = P. calvus, P. scopulifer = P. caparoensis, P. neocaldensis = P. flaccidus and P. macrotrichus = P. lundii. We also present comments on morphology, protologue and type collections. 相似文献
150.
Seiji Abe Shigeo Nakabayashi Jun‐Ichiro Murayama Yoshihiro Sano Ken‐Ichi Ohno Masako Maeda Hidetoshi Arakawa 《Luminescence》2010,25(6):456-462
Nitric oxide (NO) is related to various physiological effects as well as to numerous diseases caused by accentuation of NO production. Measurement of NO in cells and tissues is difficult as NO readily reacts with other molecules; furthermore, its half‐life as a radical is fleeting. Currently, many NO pharmaceuticals are marketed as therapeutic agents for ischemic disease. Consequently, the identification of NO radicals and determination of generation rate from pharmaceuticals is very important when the effect of the medicinal supply is estimated. In this study, we developed a fluorometric assay for NO employing sesamol (3,4‐methylenedioxyphenol) as a fluorometric substrate. Sesamol is converted to a fluorescent derivative (ex. 365 nm, em. 447 nm), which is dimmer in the presence of NO. The detection limit of NO with this method is 400 fmol; moreover, NO generated from drugs can be measured. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献