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81.
Mari Kawamura Tadashi Yamamoto Keisuke Yamashiro Shinsuke Kochi Chiaki Yoshihara‐Hirata Hidetaka Ideguchi Hiroaki Aoyagi Kazuhiro Omori Shogo Takashiba 《Journal of cellular and molecular medicine》2019,23(2):1211-1223
The recruitment of tissue‐resident stem cells is important for wound regeneration. Periodontal ligament cells (PDL cells) are heterogeneous cell populations with stemness features that migrate into wound sites to regenerate periodontal fibres and neighbouring hard tissues. Cell migration is regulated by the local microenvironment, coordinated by growth factors and the extracellular matrix (ECM). Integrin‐mediated cell adhesion to the ECM provides essential signals for migration. We hypothesized that PDL cell migration could be enhanced by selective expression of integrins. The migration of primary cultured PDL cells was induced by platelet‐derived growth factor‐BB (PDGF‐BB). The effects of blocking specific integrins on migration and ECM adhesion were investigated based on the integrin expression profiles observed during migration. Up‐regulation of integrins α3, α5, and fibronectin was identified at distinct localizations in migrating PDL cells. Treatment with anti‐integrin α5 antibodies inhibited PDL cell migration. Treatment with anti‐integrin α3, α3‐blocking peptide, and α3 siRNA significantly enhanced cell migration, comparable to treatment with PDGF‐BB. Furthermore, integrin α3 inhibition preferentially enhanced adhesion to fibronectin via integrin α5. These findings indicate that PDL cell migration is reciprocally regulated by integrin α3‐mediated inhibition and α5‐mediated promotion. Thus, targeting integrin expression is a possible therapeutic strategy for periodontal regeneration. 相似文献
82.
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
83.
84.
Keisuke Kitamura Kazuyoshi Okubo Kazuo Shibasaki 《Bioscience, biotechnology, and biochemistry》2013,77(5):1083-1085
Kinetics of the acyl transfer catalyzed by Xanthomonas α-amino acid ester hydrolase was studied. The enzyme hydrolyzed d-α-phenylglycine methyl ester (d-PG-OMe) to give equimolar amounts of d-α-phenylglycine and methanol. With d-PG-OMe as an acyl donor and 7-amino-3-deacetoxy-cephalosporanic acid (7-ADCA) as an acyl acceptor, the enzyme transferred the acyl group from d-PG-OMe to 7-ADCA in competition with water. The addition of amine nucleophiles (7-ADCA and 6-aminopenicillanic acid) decreased the molecular activity (ko) of the enzyme-catalyzed hydrolysis of d-PG-OMe, whereas it did not alter the Michaelis constant (KM), and plots of l/ko against the initial concentration of a nucleophile (no) gave a straight line. These results support the assumptions that the overall process for hydrolysis and acyl transfer proceeds through a common acyl-enzyme intermediate, that the acylation step of the enzyme is rate-limiting, and that the transfer competes with the hydrolysis of the acyl donor. 相似文献
85.
Hasegawa Y Ishida Y Kato K Ijiri R Miyake T Nishimata S Watanabe T Namba I Hayabuchi Y Kigasawa H Tanaka Y 《Acta cytologica》2003,47(4):679-684
BACKGROUND: Pancreatoblastoma (PBL) is a rare neoplasm that generally occurs in the pediatric age group and shows unique histopathology, including squamoid corpuscles that may contain tumor cells with optically clear nuclei (OCN) rich in biotin. In the English-language literature there have been two reports on the cytology of PBL, but neither of them refers to the cytologic features of squamoid corpuscles. CASE: A 3-year-old boy with nausea and general fatigue was referred to our center. Imaging studies showed an approximately 7.5-cm, left-sided abdominal mass and multiple metastases in the lung. The abdominal mass was biopsied, and its histology showed solid cellular nests with occasional acinar differentiation and squamoid corpuscles. Imprint cytology of the biopsied sample displayed cellular epithelial nests with focal acinar structures and foci composed of larger cells with a low nuclear/cytoplasmic ratio. These foci contained a few tumor cells with biotin-rich OCN and were determined to be squamoid corpuscles. CONCLUSION: Detection of occasional squamoid corpuscles with biotin-rich OCN can be useful in making a diagnosis of PBL on cytologic samples. 相似文献
86.
Upregulation of cAMP is a new functional signal pathway of Klotho in endothelial cells 总被引:3,自引:0,他引:3
Yang J Matsukawa N Rakugi H Imai M Kida I Nagai M Ohta J Fukuo K Nabeshima Y Ogihara T 《Biochemical and biophysical research communications》2003,301(2):424-429
We measured angiotensin I-converting enzyme (ACE) activity in a human endothelial cell to characterize the intracellular signal pathways of Klotho. COS-1 cells transfected with naked mouse membrane-form klotho plasmid DNA (pCAGGS-klotho) translated proper Klotho protein. This translated Klotho protein was secreted into the culture medium. Furthermore, ACE activity in human umbilical vein endothelial cells (HUVEC) was upregulated when HUVEC were co-cultured with COS-1 cells that were pre-transfected with pCAGGS-klotho. The conditioned medium from COS-1 cells pre-transfected with pCAGGS-klotho also dose-dependently upregulated ACE in HUVEC. In addition, the conditioned medium induced time- and dose-dependent enhancement of cAMP production in HUVEC. Rp-cAMP, an inhibitor of cAMP-dependent protein kinase A (PKA), inhibited the upregulation of ACE by Klotho protein. Our results suggest that mouse membrane-form Klotho protein acts as a humoral factor to increase ACE activity in HUVEC via a cAMP-PKA-dependent pathway. These findings may provide a new insight into the mechanism of Klotho protein. 相似文献
87.
Tokusei Tanahashi Keisuke Kawai Keita Tatsushima Chihiro Saeki Kunie Wakabayashi Naho Tamura Tetsuya Ando Toshio Ishikawa 《BioPsychoSocial medicine》2017,11(1):22
Background
We examined how purging behaviors relate to subjective sleep quality and sleep patterns and how symptoms of disordered eating behaviors relate to global sleep quality in female patients with anorexia nervosa (AN).Methods
Participants were new consecutive female inpatients with a primary diagnosis of AN admitted to the Department of Psychosomatic Medicine at Kohnodai Hospital between June 26 and December 25, 2015. We recorded patients’ habitual eating behaviors, laxative overuse, or uretic misuse, and administered the Japanese versions of the Pittsburgh Sleep Quality Index (PSQI-J) and Center for Epidemiologic Studies Depression Scale. Raw PSQI-J data were used to determine sleep patterns (sleep-onset time, wake-up time, and sleep duration). To examine how purging behaviors related to sleep quality, we compared variables between AN restricting type (ANr) and AN binge-eating/purging type (ANbp). Spearman’s rank correlation analysis was used to examine which potential factors influence global PSQI-J score.Results
Participants were 20 patients, of whom 12 had ANbp. Two ANr patients (25%) had global PSQI-J scores greater than 5, compared to 9 ANbp patients (75%; P < 0.05). Circadian rhythm disruption and abnormal sleep duration were significantly greater in ANbp patients than in ANr patients (P < 0.05). Global PSQI-J was significantly correlated with a diagnosis of ANbp (ρ = 0.525; P < 0.05), vomiting (ρ = 0.561; P < 0.05), and duration of illness (ρ = 0.536; P < 0.05).Conclusions
ANbp patients had worse global sleep quality and greater disrupted sleep than did ANr patients. This suggests that treatments focusing on sleep would be useful, especially for ANbp patients. Furthermore, vomiting and duration of illness should be considered essential factors related to impaired global sleep quality.Trial registration
Not applicable.88.
Nagai Y Nochi T Watanabe K Watanabe K Aso H Kitazawa H Matsuzaki M Ohwada S Yamaguchi T 《Cell and tissue research》2005,322(3):455-462
A pro-inflammatory cytokine, interleukin 18 (IL-18), induces intracellular expression of IL-1 and the release of IL-6. IL-1
and IL-6 has been detected in anterior pituitary cells, suggesting that IL-18 is produced in anterior pituitary cells and
may serve to aid immuno-endocrine regulation. In the present study, we addressed this hypothesis by investigating the intracellular
localization of IL-18 and its receptor in bovine anterior pituitary gland. IL-18 mRNA and its protein were detected in the
anterior pituitary gland by RT-PCR and Western blotting. In situ hybridization showed that IL-18 mRNA was expressed in the
anterior pituitary cells. Immunohistochemistry of IL-18 and specific hormones revealed the presence of IL-18 in somatotrophs.
Furthermore, the expression of GH mRNA in IL-18 immunoreactive cells was confirmed by immuno-laser microdissection. These
results first demonstrated that somatotrophs produced IL-18. Subsequently, the distribution of the IL-18 receptor alpha (IL-18Rα)
was investigated in order to understand IL-18 signaling among the anterior pituitary cells. Bovine IL-18Rα cDNA was partially
sequenced and detected in the anterior pituitary gland by RT-PCR. Immunohistochemistry of IL-18Rα, IL-18 and GH showed that
IL-18Rα was co-localized in IL-18 immunoreactive cells or somatotrophs. These data suggest that IL-18 acts on somatotrophs
as an immuno-endocrine mediator through the autocrine pathway.
This work was supported by a Grant-in-Aid for Scientific Research (B) (No.13460122) from the Ministry of Education, Science
and Culture of Japan 相似文献
89.
Imai D Mori K Horie-Inoue K Gehlbach PL Awata T Inoue S Yoneya S 《Journal of ocular biology, diseases, and informatics》2010,3(2):53-59
We determined whether there is an association between complement factor H (CFH), high-temperature requirement A-1 (HTRA1), vascular endothelial growth factor (VEGF), and pigment epithelium-derived factor (PEDF) genotypes and the response to treatment with a single intravitreous injection of bevacizumab for age-related macular degeneration (AMD). Eighty-three patients with exudative AMD treated by bevacizumab injection were genotyped for three single nucleotide polymorphisms (SNPs; rs800292, rs1061170, rs1410996) in the CFH gene, a rs11200638-SNP in the HTRA1 gene, three SNPs (rs699947, rs1570360, rs2010963) in the VEGF gene, and four SNPs (rs12150053, rs12948385, rs9913583, rs1136287) in the PEDF gene using a TaqMan assay. The CT genotype (heterozygous) of CFH-rs1061170 was more frequently represented in nonresponders in vision than TT genotypes (nonrisk allele homozygous) at the time points of 1 and 3 months, while there was no CC genotype (risk allele homozygous) in our study cohort (p = 7.66 × 10−3, 7.83 × 10−3, respectively). VEGF-rs699947 was also associated with vision changes at 1 month and PEDF-rs1136287 at 3 months (p = 5.11 × 10−3, 2.05 × 10−2, respectively). These variants may be utilized for genetic biomarkers to estimate visual outcomes in the response to intravitreal bevacizumab treatment for AMD. 相似文献
90.
The freshwater type of ninespine sticklebacks, genus Pungitius, is widely distributed in northern Japan and reproductively isolated from other genetically divergent types endemic to small
regions in Japan. This type expresses dimorphism in its lateral plate morphology: complete and partial row morphs. The two
morphs show a parapatric distribution in Japan. To clarify the process involving the distribution of these two morphs, we
examined their phylogeography based on restriction fragment length polymorphism of an entire mitochondrial DNA (mtDNA). The
survey was carried out with seven restriction enzymes on the populations of the freshwater type collected from 41 localities
across the distribution range in Japan, and 6 further Pungitius populations from the Okhotsk Sea coast of Russia were appended. An unweighted pair-group method with arithmetic averages
(UPGMA) tree among 54 mtDNA haplotypes resolved eight clustering groups that differed in sequence divergence by approximately
1.3%–2.1%. Two of the eight groups were found only in Russia. mtDNA phylogenies constructed by neighbor-joining and Wagner
parsimony methods suggested that the haplotypes of each plate morph were polyphyletic. The geographic distribution pattern
of these groups suggests that they should be classified into two broad categories, one with extensive distribution and the
other with localized distribution of the constituent haplotypes within a group. The former groups were found mainly in the
populations with the completely plated morph and the latter groups with the partially plated morph. It is supposed that twice
dispersals of dimorphic or complete plated ancestors and genetic differentiation during the interglacial played an important
role in the formation of the present distribution of the two morphs in Japan.
Received: March 28, 2000 / Revised: November 3, 2000 / Accepted: January 16, 2001 相似文献