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41.
Katayama Kazuhiro Hosui Atsushi Sakai Yoshiyuki Itou Minoru Matsuzaki Yasushi Takamori Yoriyuki Hosho Keiko Tsuru Tomomi Takikawa Yasuhiro Michitaka Kojiro Ogawa Eishin Miyoshi Yoko Ito Toshifumi Ida Shinobu Hamada Izumi Miyoshi Katsunori Kodama Hiroko Takehara Tetsuo 《Biological trace element research》2020,195(1):71-81
Biological Trace Element Research - The essential trace element zinc maintains liver functions. Liver diseases can alter overall zinc concentrations, and hypozincemia is associated with various... 相似文献
42.
Akihiko Shimizu Hiroyuki Tsukagoshi Tsuyoshi Sekizuka Makoto Kuroda Aya Koizumi Masahiro Fujita Yoshiyuki Yamada Nobuhiro Saruki 《Microbiology and immunology》2020,64(9):630-634
Group B streptococcus (GBS) is a leading cause of neonatal infections. Most isolates are β-hemolytic, and their activity is considered to be pivotal for GBS pathogenicity. We report a case of a neonate with meningitis caused by nonhemolytic GBS. The patient developed meningitis 3 days after birth. Genotyping was performed and the characteristics of the strain (GCMC97051) identified by whole genome sequence using next generation sequencing. GCMC97051 possesses genetic alterations such as disruption of cylA by IS1381A insertion and a frameshift mutation in cylE, resulting in a lack of hemolysis. Thus, nonhemolytic GBS can retain the potential to cause invasive infections. 相似文献
43.
Amaia Artal-Martinez de Narvajas Timothy S. Gomez Jin-San Zhang Alexander O. Mann Yoshiyuki Taoda Jacquelyn A. Gorman Marta Herreros-Villanueva Thomas M. Gress Volker Ellenrieder Luis Bujanda Do-Hyung Kim Alan P. Kozikowski Alexander Koenig Daniel D. Billadeau 《Molecular and cellular biology》2013,33(20):3983-3993
44.
Yoshie Maitani Sae Yano Yoshiyuki Hattori Masahiko Furuhata Kyoko Hayashi 《Journal of liposome research》2013,23(4):359-372
For injectable-sized liposome complexed with DNA (lipoplexes) with high transfection efficiency of genes, we initially prepared small-sized liposomes by addition of biosurfactant. For selectivity of gene expression, the thymidine kinase (MK-tk) gene controlled by midkine was used for herpes simplex virus thymidine kinase (HSV-tk) gene therapy. Liposomes composed of 3([N-(N′,N′–dimethylaminoethane)-carbamoyl] cholesterol (DC-Chol), L-dioleoylphosphatidylethanolamine (DOPE), and a biosurfactant, such as β-sitosterol β-D-glucoside (Sit-G) for Sit-G-liposomes and mannosylerythrytol lipid A (MEL) for MEL-liposomes, produced about 300-nm-sized lipoplexes. Sit-G- and MEL-liposomes showed higher transfection efficiency of the luciferase marker gene and thymidine kinase activity in the presence of serum in the cells. The treatment with transfection of MK-tk gene by Sit-G-liposome and injection of ganciclovir significantly reduced tumor growth in a solid tumor model, compared with that by Sit-G-liposome alone. This finding suggested that Sit-G-liposome is a potential vector for HSV-tk gene therapy. 相似文献
45.
Norikazu Matsumoto Tsukasa Kumai Shinji Isomoto Yasushi Shinohara Yasuhito Tanaka Cho Azuma Takeshi Minami Yoshiyuki Tohno 《Biological trace element research》2013,154(2):185-189
Many studies have been performed on the structure, molecular composition, and biochemical properties of tendons. However, comparatively little research has been conducted on the content of various trace elements within tendons. Six elements were analyzed in four regions of the peroneus longus tendon: the tensional part of the tendon immediately proximal to the lateral malleolus (region A), the compressive region of the tendon in contact with the lateral malleolus (region B), the compressive region of the tendon in contact with the deep surface of the cuboid (region C), and the tensional part of the tendon between the cuboid and first metatarsal, to which the tendon is attached (region D). Regions B and C are wraparound regions. The calcium content was higher in region C (2.10?±?0.93 mg/g) than in both regions A (1.25?±?0.51 mg/g) and D (1.43?±?0.41 mg/g) (p?<?0.05), indicating that it is likely related to regional differences in cartilage degeneration. The phosphorus content was also higher in region C, possibly because of low alkaline phosphatase activity in this region. The sulfur content was higher in the wraparound regions (region B: 0.98?±?0.09 mg/g, region C: 1.24?±?0.19 mg/g) than in both regions A (0.83?±?0.11 mg/g) and D (0.83?±?0.1 mg/g) (p?<?0.01); sulfur content is thought to be influenced by tendon–bone compression. Finally, the magnesium content in the wraparound regions was also higher, which is probably related to a higher level of fibrocartilage. No significant relationships were found with regard to zinc or iron. Overall, the findings of the present study indicate that element contents are related to function and anatomical differences in tendons, and that they may even vary within the same tendon. 相似文献
46.
Wenxiu Ye Mohammad Anowar Hossain Shintaro Munemasa Yoshimasa Nakamura Izumi C. Mori Yoshiyuki Murata 《Journal of plant physiology》2013
We recently demonstrated that endogenous abscisic acid (ABA) is involved in methyl jasmonate (MeJA)-induced stomatal closure in Arabidopsis thaliana. In this study, we investigated whether endogenous ABA is involved in MeJA-induced reactive oxygen species (ROS) and nitric oxide (NO) production and cytosolic alkalization in guard cells using an ABA-deficient Arabidopsis mutant, aba2-2, and an inhibitor of ABA biosynthesis, fluridon (FLU). The aba2-2 mutation impaired MeJA-induced ROS and NO production. FLU inhibited MeJA-induced ROS production in wild-type guard cells. Pretreatment with 0.1 μM ABA, which does not induce stomatal closure in the wild type, complemented the insensitivity to MeJA of the aba2-2 mutant. However, MeJA induced cytosolic alkalization in both wild-type and aba2-2 guard cells. These results suggest that endogenous ABA is involved in MeJA-induced ROS and NO production but not in MeJA-induced cytosolic alkalization in Arabidopsis guard cells. 相似文献
47.
Shogo Higaki Yutaka Kawakami Yoshiki Eto Etsuro Yamaha Masashi Nagano Seiji Katagiri Tatsuyuki Takada Yoshiyuki Takahashi 《Cryobiology》2013
The aim of this study was to examine the effects of partial removal of yolk and cryoprotectant mixtures on the viability of cryopreserved primordial germ cells (PGCs) and elucidated the differentiation ability of cryopreserved PGCs in zebrafish. First, dechorionated yolk-intact and yolk-depleted (partially yolk removed) embryos, PGCs of which were labeled with green fluorescence protein (GFP), were vitrified after serial exposures to pretreatment solution (PS) and vitrification solution (VS) that contained ethylene glycol (EG), dimethyl sulfoxide (Me2SO) or propylene glycol at 3 and 5 M, respectively. Although partial removal of yolk improved the viability of cryopreserved PGCs, numbers of PGCs with pseudopodial movement were limited (0–2.6 cells/embryo). Next, yolk-depleted embryos were cryopreserved using mixtures of two types of cryoprotectants. The maximum survival rate of PGCs (81%; 9.6 cells/embryo) was obtained from the yolk-depleted embryos vitrified using PS containing 2 M EG + 1 M Me2SO and VS containing 3 M EG + 2 M Me2SO and 56% (5.3 cells/embryo) of PGCs showed pseudopodial movement. Finally, PGCs recovered from yolk-depleted embryos (wild-type) that were vitrified under the optimum condition were transplanted individually into 236 sterilized recipient blastulae (recessive light-colored). Seven recipients matured and generated progeny with characteristics inherited from the PGC donor. In conclusion, the authors confirmed the beneficial effects of partial removal of yolk on the viability of cryopreserved PGCs and that the viability of the PGCs was improved by using PS and VS that contained two types of cryoprotectants, especially PS containing 2 M EG + 1 M Me2SO and VS containing 3 M EG + 2 M Me2SO, and that recovered PGCs retained ability to differentiate into functional gametes. 相似文献
48.
Yoshiyuki Inoue Keiko Nakahara Keisuke Maruyama Yoshiharu Suzuki Yujiro Hayashi Kenji Kangawa Noboru Murakami 《Biochemical and biophysical research communications》2013,430(1):278-283
In the present study using rats, we demonstrated that central and peripheral administration of des-acyl ghrelin induced a decrease in the surface temperature of the back, and an increase in the surface temperature of the tail, although the effect of peripheral administration was less marked than that of central administration. Furthermore, these effects of centrally administered des-acyl ghrelin could not be prevented by pretreatment with [D-Lys3]-GHRP-6 GH secretagogue receptor 1a (GHS-R1a) antagonists. Moreover, these actions of des-acyl ghrelin on body temperature were inhibited by the parasympathetic nerve blocker methylscopolamine but not by the sympathetic nerve blocker timolol. Using immunohistochemistry, we confirmed that des-acyl ghrelin induced an increase of cFos expression in the median preoptic nucleus (MnPO). Additionally, we found that des-acyl ghrelin dilated the aorta and tail artery in vitro. These results indicate that centrally administered des-acyl ghrelin regulates body temperature via the parasympathetic nervous system by activating neurons in the MnPO through interactions with a specific receptor distinct from the GHS-R1a, and that peripherally administered des-acyl ghrelin acts on the central nervous system by passing through the blood–brain barrier, whereas it exerts a direct action on the peripheral vascular system. 相似文献
49.
Takako Aboshi Nobuhiro Shimizu Yuji Nakajima Yoshiyuki Honda Yasumasa Kuwahara Hiroshi Amano Naoki Mori 《Insect biochemistry and molecular biology》2013,43(11):991-996
We report here that Tyrophagus similis and Tyrophagus putrescentiae (Astigmata: Acaridae) have the ability to biosynthesize linoleic acid [(9Z, 12Z)-9, 12-octadecadienoic acid] via a Δ12-desaturation step, although animals in general and vertebrates in particular appear to lack this ability. When the mites were fed on dried yeast enriched with d31-hexadecanoic acid (16:0), d27-octadecadienoic acid (18:2), produced from d31-hexadecanoic acid through elongation and desaturation reactions, was identified as a major fatty acid component of phosphatidylcholines (PCs) and phosphatidylethanolamines (PEs) in the mites. The double bond position of d27-octadecadienoic acid (18:2) of PCs and PEs was determined to be 9 and 12, respectively by dimethyldisulfide (DMDS) derivatization. Furthermore, the GC/MS retention time of methyl 9, 12-octadecadienoate obtained from mite extracts agreed well with those of authentic linoleic acid methyl ester. It is still unclear whether the mites themselves or symbiotic microorganisms are responsible for inserting a double bond into the Δ12 position of octadecanoic acid. However, we present here the unique metabolism of fatty acids in the mites. 相似文献
50.
Isoko Kuriyama Anna Miyazaki Yuko Tsuda Hiromi Yoshida Yoshiyuki Mizushina 《Bioorganic & medicinal chemistry》2013,21(2):403-411
The present study was designed to investigate the anticancer activity of novel nine small peptides (compounds 1–9) derived from TT-232, a somatostatin structural analogue, by analyzing the inhibition of mammalian DNA polymerase (pol) and human cancer cell growth. Among the compounds tested, compounds 3 [tert-butyloxycarbonyl (Boc)-Tyr-Phe-1-naphthylamide], 4 (Boc-Tyr-Ile-1-naphthylamide), 5 (Boc-Tyr-Leu-1-naphthylamide) and 6 (Boc-Tyr-Val-1-naphthylamide) containing tyrosine (Tyr) but no carboxyl groups, selectively inhibited the activity of rat pol β, which is a DNA repair-related pol. Compounds 3–6 strongly inhibited the growth of human colon carcinoma HCT116 p53+/+ cells. The influence of compounds 1–9 on HCT116 p53?/? cell growth was similar to that observed for HCT116 p53+/+ cells. These results suggest that the cancer cell growth suppression induced by these compounds might be related to their inhibition of pol. Compound 4 was the strongest inhibitor of pol β and cancer cell growth among the nine compounds tested. This compound specifically inhibited rat pol β activity, but had no effect on the other 10 mammalian pols investigated. Compound 4 combined with methyl methane sulfonate (MMS) treatment synergistically suppressed HCT116 p53?/? cell growth compared with MMS alone. This compound also induced apoptosis in HCT116 cells with or without p53. From these results, the influence of compound 4, a specific pol β inhibitor, on the relationship between DNA repair and cancer cell growth is discussed. 相似文献