Search

Your search keyword '"Azuma, Sadahiro"' showing total 31 results
Start Over Author "Azuma, Sadahiro"
31 results on '"Azuma, Sadahiro"'

3. Metallothionein is a crucial protective factor against Helicobacter pylori-induced gastric erosive lesions in a mouse model

Author

Mita, Masaharu, Satoh, Masahiko, Shimada, Akinori, Okajima, Mina, Azuma, Sadahiro, Suzuki, Junko S., Sakabe, Kou, Hara, Shuntaro, and Himeno, Seiichiro

Subjects
Helicobacter pylori -- Health aspects, Helicobacter pylori -- Control, Helicobacter pylori -- Research, Metallothionein -- Health aspects, Metallothionein -- Research, Stomach ulcer -- Risk factors, Stomach ulcer -- Research, Biological sciences
Abstract

Infection with the gastric pathogen Helicobacter pylori (H. pylori) causes chronic gastritis, peptic ulcer, and gastric adenocarcinoma. These diseases are associated with production of reactive oxygen species (ROS) from infiltrated macrophages and neutrophiles in inflammatory sites. Metallothionein (MT) is a low-molecular-weight, cysteine-rich protein that can act not only as a metal-binding protein, but also as a ROS scavenger. In the present study, we examined the role of MT in the protection against H. pylori-induced gastric injury using MT-null mice. Female MT-null and wild-type mice were challenged with H. pylori SS1 strain, and then histological changes were evaluated with the updated Sydney grading system at 17 and 21 wk after challenge. Although the colonization efficiency of H. pylori was essentially the same for MT-null and wild-type mice, the scores of activity of inflammatory cells were significantly higher in MT-null mice than in wild-type mice at 17 wk after challenge. Histopathological examination revealed erosive lesions accompanied by infiltration of inflammatory cells in the infected MT-null mice but not in wild-type mice. Furthermore, activation of NF-KB and expression of NF-KB-mediated chemokines such as macrophage inflammatory protein-IoL and monocytes chemoattractant protein-1 in gastric cells were markedly higher in MT-null mice than in wild-type mice. These results suggest that MT in the gastric mucosa might play an important role in the protection against H. pylori-induced gastric ulceration. gastric ulcer; reactive oxygen species; NF-KB; chemokine

Published
2008

6. A role for macrophage scavenger receptors in atherosclerosis and susceptibility to infection

Author

Suzuki, Hiroshi, Kurihara, Yukiko, Takeya, Motohiro, Kamada, Nobuo, Kataoka, Motoyuki, Jishage, Kouichi, Ueda, Otoya, Sakaguchi, Hisashi, Higashi, Takayuki, Suzuki, Tsukasa, Takashima, Yoshiaki, Kawabe, Yoshiki, Cynshi, Osamu, Wada, Youichiro, Honda, Makoto, Kurihara, Hiroki, Aburatani, Hiroyuki, Doi, Takefumi, Matsumoto, Akiyo, Azuma, Sadahiro, Noda, Tetsuo, Toyoda, Yutaka, Itakura, Hiroshige, Yazaki, Yoshio, Horiuchi, Seikoh, Takahashi, Kiyoshi, Kruijt, J. Kar, Berkel, Theo J.C. van, Steinbrecher, Urs P., Ishibashi, Shun, Maeda, Nobuyo, Gordon, Siamon, and Kodama, Tatsuhiko

Subjects
Macrophages -- Research, Atherosclerosis -- Microbiology, Infection -- Microbiology, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Targeted disruption of the macrophage type-I and type-II class-A scavenger receptors (MSR-A) gene in mice results in size reduction of atherosclerotic lesions in an animal deficient in apolipoprotein E. Macrophages from these deficient mice reveal a marked decrease in the in vitro uptake of modified low-density lipoproteins (mLDL), whereas mLDL clearance from plasma occurs at a normal rate. This indicates that alternative mechanisms for removing mLDL from the circulation exist. MSR-A may also play a role in host defense against pathogens.

Published
1997

7. Elevated blood pressure and craniofacial abnormalities in mice deficient in endothelin-1

Author

Kurihara, Yukiko, Kurihara, Hiroki, Suzuki, Hiroshi, Kodama, Tatsuhiko, Maemura, Koji, Nagai, Ryozo, Oda, Hideaki, Kuwaki, Tomoyuki, Cao, Wei-Hua, Kamada, Nobuo, Jishage, Kouichi, Ouchi, Yasuyoshi, Azuma, Sadahiro, Toyoda, Yutaka, Ishikawa, Takatoshi, Kumada, Mamoru, and Yazaki, Yoshio

Subjects
Endothelin -- Genetic aspects, Homeostasis -- Research, Mice -- Growth, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Studies on ET-1-/- homozygous mice with disrupted endothelin-1 (ET-1) genes reveal that the ET-1 gene is vital for normal mouse development and may also be involved in cardiovascular homeostasis. The ET-1-/- mice die at birth due to respiratory failure and exhibit abnormal craniofacial tissues and organs. ET-1+/- heterozygous mice exhibit elevated blood pressure.

Published
1994

8. The I2020T Leucine-rich repeat kinase 2 transgenic mouse exhibits impaired locomotive ability accompanied by dopaminergic neuron abnormalities

Author

Maekawa Tatsunori, Mori Sayuri, Sasaki Yui, Miyajima Takashi, Azuma Sadahiro, Ohta Etsuro, and Obata Fumiya

Subjects
Parkinson’s disease, LRRK2, Transgenic mouse, Neurology. Diseases of the nervous system, RC346-429, Geriatrics, RC952-954.6
Abstract

Abstract Background Leucine-rich repeat kinase 2 (LRRK2) is the gene responsible for autosomal-dominant Parkinson’s disease (PD), PARK8, but the mechanism by which LRRK2 mutations cause neuronal dysfunction remains unknown. In the present study, we investigated for the first time a transgenic (TG) mouse strain expressing human LRRK2 with an I2020T mutation in the kinase domain, which had been detected in the patients of the original PARK8 family. Results The TG mouse expressed I2020T LRRK2 in dopaminergic (DA) neurons of the substantia nigra, ventral tegmental area, and olfactory bulb. In both the beam test and rotarod test, the TG mice exhibited impaired locomotive ability in comparison with their non-transgenic (NTG) littermates. Although there was no obvious loss of DA neurons in either the substantia nigra or striatum, the TG brain showed several neurological abnormalities such as a reduced striatal dopamine content, fragmentation of the Golgi apparatus in DA neurons, and an increased degree of microtubule polymerization. Furthermore, the tyrosine hydroxylase-positive primary neurons derived from the TG mouse showed an increased frequency of apoptosis and had neurites with fewer branches and decreased outgrowth in comparison with those derived from the NTG controls. Conclusions The I2020T LRRK2 TG mouse exhibited impaired locomotive ability accompanied by several dopaminergic neuron abnormalities. The TG mouse should provide valuable clues to the etiology of PD caused by the LRRK2 mutation.

Published
2012
Full Text
View/download PDF

12. A Single Amino Acid Mutation in SNAP-25 Induces Anxiety-Related Behavior in Mouse

Author

Kataoka, Masakazu, primary, Yamamori, Saori, additional, Suzuki, Eiji, additional, Watanabe, Shigeru, additional, Sato, Taku, additional, Miyaoka, Hitoshi, additional, Azuma, Sadahiro, additional, Ikegami, Shiro, additional, Kuwahara, Reiko, additional, Suzuki-Migishima, Rika, additional, Nakahara, Yohko, additional, Nihonmatsu, Itsuko, additional, Inokuchi, Kaoru, additional, Katoh-Fukui, Yuko, additional, Yokoyama, Minesuke, additional, and Takahashi, Masami, additional

Published
2011
Full Text
View/download PDF

13. Profile of new green fluorescent protein transgenic Jinhua pigs as an imaging source

Author

Kawarasaki, Tatsuo, primary, Uchiyama, Kazuhiko, additional, Hirao, Atsushi, additional, Azuma, Sadahiro, additional, Otake, Masayoshi, additional, Shibata, Masatoshi, additional, Tsuchiya, Seiko, additional, Enosawa, Shin, additional, Takeuchi, Koichi, additional, Konno, Kenjiro, additional, Hakamata, Yoji, additional, Yoshino, Hiroyuki, additional, Wakai, Takuya, additional, Ookawara, Shigeo, additional, Tanaka, Hozumi, additional, Kobayashi, Eiji, additional, and Murakami, Takashi, additional

Published
2009
Full Text
View/download PDF

19. Germ-Line Contribution of Embryonic Stem Cells in Chimeric Mice: Influence of Karyotype and In Vitro Differentiation Ability.

Author

SUZUKI, Hiroshi, primary, KAMADA, Nobuo, additional, UEDA, Otoya, additional, JISHAGE, Kouichi, additional, KURIHARA, Yukiko, additional, KURIHARA, Hiroki, additional, TERAUCHI, Yasuo, additional, AZUMA, Sadahiro, additional, KADOWAKI, Takashi, additional, KODAMA, Tatsuhiko, additional, YAZAKI, Yoshio, additional, and TOYODA, Yutaka, additional

Published
1997
Full Text
View/download PDF

23. Mice deficient for the IL-3/GM-CSF/IL-5 βc receptor exhibit lung pathology and impaired immune response, while βIL3 receptor-deficient mice are normal

Author

Nishinakamura, Ryuichi, primary, Nakayama, Naoki, additional, Hirabayashi, Yoko, additional, Inoue, Tohru, additional, Aud, Dee, additional, Mcneil, Tom, additional, Azuma, Sadahiro, additional, Yoshida, Shosei, additional, Toyoda, Yutaka, additional, Aral, Ken-ichi, additional, Miyajima, Atsushi, additional, and Murray, Richard, additional

Published
1995
Full Text
View/download PDF

31. Targeted Disruption of Na+/Ca2+Exchanger Gene Leads to Cardiomyocyte Apoptosis and Defects in Heartbeat*

Author

Wakimoto, Koji, Kobayashi, Kinji, Kuro-o, Makoto, Yao, Atsushi, Iwamoto, Takahiro, Yanaka, Noriyuki, Kita, Satomi, Nishida, Atsuyuki, Azuma, Sadahiro, Toyoda, Yutaka, Omori, Kenji, Imahie, Hiroshi, Oka, Toru, Kudoh, Sumiyo, Kohmoto, Osami, Yazaki, Yoshio, Shigekawa, Munekazu, Imai, Yuji, Nabeshima, Yo-ichi, and Komuro, Issei

Abstract

Ca2+, which enters cardiac myocytes through voltage-dependent Ca2+channels during excitation, is extruded from myocytes primarily by the Na+/Ca2+exchanger (NCX1) during relaxation. The increase in intracellular Ca2+concentration in myocytes by digitalis treatment and after ischemia/reperfusion is also thought to result from the reverse mode of the Na+/Ca2+exchange mechanism. However, the precise roles of the NCX1 are still unclear because of the lack of its specific inhibitors. We generated Ncx1-deficient mice by gene targeting to determine the in vivofunction of the exchanger. Homozygous Ncx1-deficient mice died between embryonic days 9 and 10. Their hearts did not beat, and cardiac myocytes showed apoptosis. No forward mode or reverse mode of the Na+/Ca2+exchange activity was detected in null mutant hearts. The Na+-dependent Ca2+exchange activity as well as protein content of NCX1 were decreased by ∼50% in the heart, kidney, aorta, and smooth muscle cells of the heterozygous mice, and tension development of the aortic ring in Na+-free solution was markedly impaired in heterozygous mice. These findings suggest that NCX1 is required for heartbeats and survival of cardiac myocytes in embryos and plays critical roles in Na+-dependent Ca2+handling in the heart and aorta.

Published
2000
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results