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61.
Yosuke Kanno Akira Ishisaki Eri Kawashita Hiromi Kuretake Kanako Ikeda Osamu Matsuo 《International journal of biological sciences》2016,12(1):63-71
Chronic inflammatory diseases, such as rheumatoid arthritis and periodontitis-caused bone destruction, results from an increase of bone-resorbing osteoclasts (OCs) induced by inflammation. However, the detailed mechanisms underlying this disorder remain unclear. We herein investigated that the effect of urokinase-type plasminogen activator (uPA) on inflammatory osteoclastogenesis induced by lipopolysaccharide (LPS), which is a potent stimulator of bone resorption in inflammatory diseases. We found that the uPA deficiency promoted inflammatory osteoclastogenesis and bone loss induced by LPS. We also showed that LPS induced the expression of uPA, and the uPA treatment attenuated the LPS-induced inflammatory osteoclastogenesis of RAW264.7 mouse monocyte/macrophage lineage cells. Additionally, we showed that the uPA-attenuated inflammatory osteoclastgenesis is associated with the activation of plasmin/protease-activated receptor (PAR)-1 axis by uPA. Moreover, we examined the mechanism underlying the effect of uPA on inflammatory osteoclastogenesis, and found that uPA/plasmin/PAR-1 activated the adenosine monophosphate-activated protein kinase (AMPK) pathway through Ca2+/calmodulin dependent protein kinase kinase (CaMKK) activation, and attenuated inflammatory osteoclastogenesis by inactivation of NF-κB in RAW264.7 cells. These data suggest that uPA attenuated inflammatory osteoclastogenesis through the plasmin/PAR-1/Ca2+/CaMKK/AMPK axis. Our findings may provide a novel therapeutic approach to bone loss caused by inflammatory diseases. 相似文献
62.
Tohru Taniguchi Mai Asahata Akihito Nasu Yukatsu Shichibu Katsuaki Konishi Kenji Monde 《Chirality》2016,28(7):534-539
Separation of the diastereomers of glycosyl sulfoxides differing in the sulfur chirality has been difficult. This article presents a fast and scalable method for their diastereoseparation using a chiral stationary phase. The usefulness of this method was demonstrated in a 500‐mg scale separation within 20 min, and in the separation of trisaccharyl sulfoxide diastereomers. Chirality 28:534–539, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
63.
Kazuma Okada Masato Wada Shigeki Moriya Yuichi Katayose Hiroko Fujisawa Jianzhong Wu Hiroyuki Kanamori Kanako Kurita Harumi Sasaki Hiroshi Fujii Shingo Terakami Hiroshi Iwanami Toshiya Yamamoto Kazuyuki Abe 《Journal of plant research》2016,129(6):1109-1126
Determining the molecular mechanism of fruit tree architecture is important for tree management and fruit production. An apple mutant ‘McIntosh Wijcik’, which was discovered as a bud mutation from ‘McIntosh’, exhibits a columnar growth phenotype that is controlled by a single dominant gene, Co. In this study, the mutation and the Co gene were analyzed. Fine mapping narrowed the Co region to a 101 kb region. Sequence analysis of the Co region and the original wild-type co region identified an insertion mutation of an 8202 bp long terminal repeat (LTR) retroposon in the Co region. Segregation analysis using a DNA marker based on the insertion polymorphism showed that the LTR retroposon was closely associated with the columnar growth phenotype. RNA-seq and RT-PCR analysis identified a promising Co candidate gene (91071-gene) within the Co region that is specifically expressed in ‘McIntosh Wijcik’ but not in ‘McIntosh’. The 91071-gene was located approximately 16 kb downstream of the insertion mutation and is predicted to encode a 2-oxoglutarate-dependent dioxygenase involved in an unknown reaction. Overexpression of the 91071-gene in transgenic tobaccos and apples resulted in phenotypes with short internodes, like columnar apples. These data suggested that the 8202 bp retroposon insertion in ‘McIntosh Wijcik’ is associated with the short internodes of the columnar growth phenotype via upregulated expression of the adjacent 91071-gene. Furthermore, the DNA marker based on the insertion polymorphism could be useful for the marker-assisted selection of columnar apples. 相似文献
64.
Mature plant cells have large vacuoles. But how these vacuoles are formed has not been fully understood. It has been reported that autophagy is involved in the genesis of plant vacuoles. Thus we examined whether autophagy occurs in the vacuole genesis of a plant cell model called miniprotoplasts, in which preexisting large vacuoles have been removed. We prepared miniprotoplasts from tobacco culture cells (BY-2) and observed the formation of vacuoles by light and electron microscopy. The miniprotoplasts had few vacuoles immediately after preparation, but had large vacuoles after 1 to 2 d. When the cysteine protease inhibitor E-64c or E-64d was added to culture media, almost all vacuoles formed contained materials of cytoplasmic origin. This result suggests that autophagy occurs together with the genesis of the vacuoles in miniprotoplasts. 3-Methyladenine and phosphatidylinositol 3-kinase inhibitors such as wortmannin and LY294002, all of which block starvation?induced autophagy in tobacco culture cells and constitutive autophagy in Arabidopsis root cells, did not affect the autophagy in miniprotoplasts. Thus the form of autophagy in miniprotoplasts is probably different from the form of autophagy that arises as a result of sucrose starvation and constitutive autophagy in root tip cells. The causal connection between autophagy and vacuole genesis in miniprotoplasts was not clarified in this study. 相似文献
65.
Hydrogen production by termite gut protists: characterization of iron hydrogenases of Parabasalian symbionts of the termite Coptotermes formosanus
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Cellulolytic flagellated protists in the guts of termites produce molecular hydrogen (H(2)) that is emitted by the termites; however, little is known about the physiology and biochemistry of H(2) production from cellulose in the gut symbiotic protists due to their formidable unculturability. In order to understand the molecular basis for H(2) production, we here identified two genes encoding proteins homologous to iron-only hydrogenases (Fe hydrogenases) in Pseudotrichonympha grassii, a large cellulolytic symbiont in the phylum Parabasalia, in the gut of the termite Coptotermes formosanus. The two Fe hydrogenases were phylogenetically distinct and had different N-terminal accessory domains. The long-form protein represented a phylogenetic lineage unique among eukaryotic Fe hydrogenases, whereas the short form was monophyletic with those of other parabasalids. Active recombinant enzyme forms of these two Fe hydrogenases were successfully obtained without the specific auxiliary maturases. Although they differed in their extent of specific activity and optimal pH, both enzymes preferentially catalyzed H(2) evolution rather than H(2) uptake. H(2) evolution, at least that associated with the short-form enzyme, was still active even under high hydrogen partial pressure. H(2) evolution activity was detected in the hydrogenosomal fraction of P. grassii cells; however, the vigorous H(2) uptake activity of the endosymbiotic bacteria compensated for the strong H(2) evolution activity of the host protists. The results suggest that termite gut symbionts are a rich reservoir of novel Fe hydrogenases whose properties are adapted to the gut environment and that the potential of H(2) production in termite guts has been largely underestimated. 相似文献
66.
Rapid SNP diagnostics using asymmetric isothermal amplification and a new mismatch-suppression technology 总被引:2,自引:0,他引:2
Mitani Y Lezhava A Kawai Y Kikuchi T Oguchi-Katayama A Kogo Y Itoh M Miyagi T Takakura H Hoshi K Kato C Arakawa T Shibata K Fukui K Masui R Kuramitsu S Kiyotani K Chalk A Tsunekawa K Murakami M Kamataki T Oka T Shimada H Cizdziel PE Hayashizaki Y 《Nature methods》2007,4(3):257-262
We developed a rapid single nucleotide polymorphism (SNP) detection system named smart amplification process version 2 (SMAP 2). Because DNA amplification only occurred with a perfect primer match, amplification alone was sufficient to identify the target allele. To achieve the requisite fidelity to support this claim, we used two new and complementary approaches to suppress exponential background DNA amplification that resulted from mispriming events. SMAP 2 is isothermal and achieved SNP detection from whole human blood in 30 min when performed with a new DNA polymerase that was cloned and isolated from Alicyclobacillus acidocaldarius (Aac pol). Furthermore, to assist the scientific community in configuring SMAP 2 assays, we developed software specific for SMAP 2 primer design. With these new tools, a high-precision and rapid DNA amplification technology becomes available to aid in pharmacogenomic research and molecular-diagnostics applications. 相似文献
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69.
According to a report from the World Health Organization (WHO), the mortality and disease severity induced by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are significantly higher in cancer patients than those of individuals with no known condition. Common and cancer-specific risk factors might be involved in the mortality and severity rates observed in the coronavirus disease 2019 (COVID-19). Similarly, various factors might contribute to the aggravation of COVID-19 in patients with cancer. However, the factors involved in the aggravation of COVID-19 in cancer patients have not been fully investigated so far. The formation of metastases in other organs is common in cancer patients. Therefore, the present study investigated the association between lung metastatic lesion formation and SARS-CoV-2 infectivity. In the pulmonary micrometastatic niche of patients with ovarian cancer, alveolar epithelial stem-like cells were found adjacent to ovarian cancer. Moreover, angiotensin-converting enzyme 2, a host-side receptor for SARS-CoV-2, was expressed in these alveolar epithelial stem-like cells. Furthermore, the spike glycoprotein receptor-binding domain (RBD) of SARS-CoV-2 was bound to alveolar epithelial stem-like cells. Altogether, these data suggested that patients with cancer and pulmonary micrometastases are more susceptible to SARS-CoV-2. The prevention of de novo niche formation in metastatic diseases might constitute a new strategy for the clinical treatment of COVID-19 for patients with cancer. 相似文献
70.
Akihiro Kuno Yoshihisa Ikeda Shinya Ayabe Kanako Kato Kotaro Sakamoto Sayaka R. Suzuki Kento Morimoto Arata Wakimoto Natsuki Mikami Miyuki Ishida Natsumi Iki Yuko Hamada Megumi Takemura Yoko Daitoku Yoko Tanimoto Tra Thi Huong Dinh Kazuya Murata Michito Hamada Masafumi Muratani Atsushi Yoshiki Fumihiro Sugiyama Satoru Takahashi Seiya Mizuno 《PLoS biology》2022,20(1)
Genome editing can introduce designed mutations into a target genomic site. Recent research has revealed that it can also induce various unintended events such as structural variations, small indels, and substitutions at, and in some cases, away from the target site. These rearrangements may result in confounding phenotypes in biomedical research samples and cause a concern in clinical or agricultural applications. However, current genotyping methods do not allow a comprehensive analysis of diverse mutations for phasing and mosaic variant detection. Here, we developed a genotyping method with an on-target site analysis software named Determine Allele mutations and Judge Intended genotype by Nanopore sequencer (DAJIN) that can automatically identify and classify both intended and unintended diverse mutations, including point mutations, deletions, inversions, and cis double knock-in at single-nucleotide resolution. Our approach with DAJIN can handle approximately 100 samples under different editing conditions in a single run. With its high versatility, scalability, and convenience, DAJIN-assisted multiplex genotyping may become a new standard for validating genome editing outcomes.Genome editing can introduce designed mutations into a target genomic site, but also into unintended off-target sites. DAJIN, a novel nanopore sequencing data analysis tool, identifies and quantifies allele numbers and their mutation patterns, reporting consensus sequences and visualizing mutations in alleles at single-nucleotide resolution. 相似文献