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101.
Fumiya Noguchi Masaru Kawato Takao Yoshida Yoshihiro Fujiwara Katsunori Fujikura Kiyotaka Takishita 《The Journal of eukaryotic microbiology》2013,60(2):158-165
It has recently been unveiled that a wide variety of microbial eukaryotes (protists) occur in chemosynthetic ecosystems, such as hydrothermal vents and methane seeps. However, there is little knowledge regarding protists associated with endemic animals inhabiting these environments. In the present study, utilizing PCR techniques, we detected fragments of the small subunit ribosomal RNA gene (SSU rRNA gene) from a particular protist from gill tissues of a significant fraction of the vesicomyid clams Calyptogena soyoae and C. okutanii complex and of the mussel Bathymodiolus platifrons and B. japonicus, all of which harbor chemosynthetic endosymbiont bacteria and dominate methane seeps in Sagami Bay, Japan. Based on the phylogeny of SSU rRNA gene, the organism in question was shown to belong to Alveolata. It is noteworthy that this protist did not affiliate with any known alveolate group, although being deeply branched within the lineage of Syndiniales, for which the monophyly was constantly recovered, but not robustly supported. In addition, the protist detected using PCR followed by sequencing was localized within gill epithelial cells of B. platifrons with whole‐mount fluorescence in situ hybridization. This protist may be an endoparasite or an endocommensal of Calyptogena spp. and Bathymodiolus spp., and possibly have physiological and ecological impacts on these bivalves. 相似文献
102.
Keitarou Suzuki Yoshikazu Terasaki Masaru Uyeda 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):183-186
The inhibitory effects of various fatty acids on three hyaluronidases (h-ST, h-SH and h-SD) and four chondroitinases (c-ABC, c-B, c-ACI and c-ACII) were examined, and their structure-activity relationships and mechanism of action were studied. The fatty acids used in this experiment showed various inhibitory activities against the enzymes. None of the fatty acids did not inhibit h-ST and h-SH. The saturated fatty acids (C 10:0 to C 22:0) showed very weak or no inhibition against h-SD, c-ABC, c-B, c-ACI and c-ACII but the unsaturated fatty acids (C 14:1 to C 24:1) with one double bond strongly inhibited the enzymes, and the inhibitory potency increased with increase in carbon chain length of the fatty acids. In contrast, the increase in number of double bonds caused a decrease in inhibitory potency against the enzymes. The position of the double bond and the stereochemistry of the cis - trans form of oleic acid (C 18:1) did not influence the inhibitory potency against the enzymes. Carboxyl and hydroxyl groups in the fatty acid molecule were concerned in the inhibition of c-ACI. Among the fatty acids, eicosatrienoic acid (C 20:3) generally inhibited h-SD, c-ABC, c-B and c-ACI, and nervonic acid (C 24:1) was a potent inhibitor of c-ACII, and the fatty acids inhibited the enzymes in a noncompetitive manner. 相似文献
103.
John Paul Wanner Roopashree Subbaiah Yelenna Skomorovska-Prokvolit Yousef Shishani Eric Boilard Sujatha Mohan Robert Gillespie Masaru Miyagi Reuben Gobezie 《Arthritis research & therapy》2013,15(6):R180
Introduction
The development of effective treatments for osteoarthritis (OA) has been hampered by a poor understanding of OA at the cellular and molecular levels. Emerging as a disease of the ''whole joint’, the importance of the biochemical contribution of various tissues, including synovium, bone and articular cartilage, has become increasingly significant. Bathing the entire joint structure, the proteomic analysis of synovial fluid (SF) from osteoarthritic shoulders offers a valuable ''snapshot’ of the biologic environment throughout disease progression. The purpose of this study was to identify differentially expressed proteins in early and late shoulder osteoarthritic SF in comparison to healthy SF.Methods
A quantitative 18O labeling proteomic approach was employed to identify the dysregulated SF proteins in early (n = 5) and late (n = 4) OA patients compared to control individuals (n = 5). In addition, ELISA was used to quantify six pro-inflammatory and two anti-inflammatory cytokines.Results
Key results include a greater relative abundance of proteins related to the complement system and the extracellular matrix in SF from both early and late OA. Pathway analyses suggests dysregulation of the acute phase response, liver x receptor/retinoid x receptor (LXR/RXR), complement system and coagulation pathways in both early and late OA. The network related to lipid metabolism was down-regulated in both early and late OA. Inflammatory cytokines including interleukin (IL) 6, IL 8 and IL 18 were up-regulated in early and late OA.Conclusions
The results suggest a dysregulation of wound repair pathways in shoulder OA contributing to the presence of a ''chronic wound’ that progresses irreversibly from early to later stages of OA. Protease inhibitors were downregulated in late OA suggesting uncontrolled proteolytic activity occurring in late OA. These results contribute to the theory that protease inhibitors represent promising therapeutic agents which could limit proteolytic activity that ultimately leads to cartilage destruction. 相似文献104.
Structure and function of abscisic acid receptors 总被引:2,自引:0,他引:2
105.
Masaru Ishii Junichi Kikuta 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(1):223-227
Bone is a dynamic organ that is continuously turned over during growth, even in adults. During bone remodeling, homeostasis is regulated by the balance between bone formation by osteoblasts and bone resorption by osteoclasts. However, in pathological conditions such as osteoporosis, osteopetrosis, arthritic joint destruction, and bone metastasis, this equilibrium is disrupted. Since osteoclasts are excessively activated in osteolytic diseases, the inhibition of osteoclast function has been a major therapeutic strategy. It has recently been demonstrated that sphingosine-1-phosphate (S1P), a biologically active lysophospholipid that is enriched in blood, controls the trafficking of osteoclast precursors between the circulation and bone marrow cavities via G protein-coupled receptors, S1PRs. While S1PR1 mediates chemoattraction toward S1P in bone marrow, where S1P concentration is low, S1PR2 mediates chemorepulsion in blood, where the S1P concentration is high. The regulation of precursor recruitment may represent a novel therapeutic strategy for controlling osteoclast-dependent bone remodeling. By means of intravital multiphoton imaging of bone tissues, we have recently revealed that the reciprocal action of S1P controls the migration of osteoclast precursors between bone tissues and blood stream. Imaging technologies have enabled us to visualize the in situ behaviors of different cell types in intact tissues. In this review we also discuss future perspectives on this new method in the field of bone biology and medical sciences in general. This article is part of a Special Issue entitled Advances in Lysophospholipid Research. 相似文献
106.
Saki Nagano-Koyashiki Makoto Matsubayashi Isao Kimata Masaru Furuya Hiroyuki Tani Kazumi Sasai 《Parasitology international》2013,62(2):109-111
Cryptosporidium andersoni is a protozoan parasite found in many countries that invades the stomachs of primarily adult cattle. Unlike the isolates of C. andersoni in cattle from other countries, C. andersoni isolates from Japanese cattle can infect mice and were identified as a novel type and later defined as C. andersoni Kawatabi type. The biological characteristics of C. andersoni Kawatabi type have not yet been well documented. In the present study, we assess the infectivity of this type isolate in mice with different immune competence status and age. We found that inoculation of more than 1 × 104 oocysts is needed to establish infection in mature mice irrespective of immune status. All of the infected immunocompetent mice recovered after a patent period of approximately 20 days. In immunodeficient mice, the pre-patent period was prolonged compared with that of 1 × 106 oocysts, but the pattern and the maximum shedding measured by the number of oocysts per day were almost identical. In neonatal immunocompetent and immunodeficient mice, inoculation with 1 × 104 to 105 oocysts was also needed to establish infection. Our results indicate that there is a threshold of oocysts needed to establish patent infection in the acidic conditions of the stomach. 相似文献
107.
Identification of a replication initiation protein of the pVV8 plasmid from Thermus thermophilus HB8
Naoto Ohtani Masaru Tomita Mitsuhiro Itaya 《Extremophiles : life under extreme conditions》2013,17(1):15-28
Recently, the extremely thermophilic bacterium Thermus thermophilus HB8 has been demonstrated to harbor a circular plasmid designated by pVV8 in addition to two well-known plasmids, pTT8 and pTT27, and its entire sequence has been determined. The absence of any obvious replication initiation gene in the 81.2 kb plasmid prompted us to isolate its minimum replicon. By in vivo replication assays with fragments deleted in a stepwise manner, a minimum replicon containing a single ORF, TTHV001, was identified. A protein encoded by TTHV001 showed no amino acid sequence similarity to other function-known proteins. As the results of in vivo and in vitro experiments strongly suggested that the TTHV001 protein was involved in the replication initiation of pVV8, the protein and the gene were referred to as RepV and repV, respectively. The RepV protein binds to an inverted repeat sequence within its own repV gene and then triggers the unwinding of the DNA duplex in an A + T-rich region located just downstream from the inverted repeat. The in vivo replication assays with minimum replicon mutants in the RepV binding site or the unwinding region demonstrated that the unwinding in the region by the RepV binding was essential for pVV8 replication initiation. 相似文献
108.
Takao Tanahashi Tomohisa Yamamoto Takuyuki Endo Harutoshi Fujimura Masaru Yokoe Hideki Mochizuki Taishin Nomura Saburo Sakoda 《PloS one》2013,8(12)
Freezing of gait in patients with Parkinson’s disease is associated with several factors, including interlimb incoordination and impaired gait cycle regulation. Gait analysis in patients with Parkinson’s disease is confounded by parkinsonian symptoms such as rigidity. To understand the mechanisms underlying freezing of gait, we compared gait patterns during straight walking between 9 patients with freezing of gait but little to no parkinsonism (freezing patients) and 11 patients with Parkinson’s disease (non-freezing patients). Wireless sensors were used to detect foot contact and toe-off events, and the step phase of each foot contact was calculated by defining one stride cycle of the other leg as 360°. Phase-resetting analysis was performed, whereby the relation between the step phase of one leg and the subsequent phase change in the following step of the other leg was quantified using regression analysis. A small slope of the regression line indicates a forceful correction (phase reset) at every step of the deviation of step phase from the equilibrium phase, usually at around 180°. The slope of this relation was smaller in freezing patients than in non-freezing patients, but the slope exhibited larger step-to-step variability. This indicates that freezing patients executed a forceful but noisy correction of the deviation of step phase, whereas non-freezing patients made a gradual correction of the deviation. Moreover, freezing patients tended to show more variable step phase and stride time than non-freezing patients. Dynamics of a model of two coupled oscillators interacting through a phase resetting mechanism were examined, and indicated that the deterioration of phase reset by noise provoked variability in step phase and stride time. That is, interlimb coordination can affect regulation of the gait cycle. These results suggest that noisy interlimb coordination, which probably caused forceful corrections of step phase deviation, can be a cause of freezing of gait. 相似文献
109.
Tomoyuki Yamanaka Asako Tosaki Masaru Kurosawa Kazunori Akimoto Tomonori Hirose Shigeo Ohno Nobutaka Hattori Nobuyuki Nukina 《PloS one》2013,8(12)
Cell polarity plays a critical role in neuronal differentiation during development of the central nervous system (CNS). Recent studies have established the significance of atypical protein kinase C (aPKC) and its interacting partners, which include PAR-3, PAR-6 and Lgl, in regulating cell polarization during neuronal differentiation. However, their roles in neuronal maintenance after CNS development remain unclear. Here we performed conditional deletion of aPKCλ, a major aPKC isoform in the brain, in differentiated neurons of mice by camk2a-cre or synapsinI-cre mediated gene targeting. We found significant reduction of aPKCλ and total aPKCs in the adult mouse brains. The aPKCλ deletion also reduced PAR-6β, possibly by its destabilization, whereas expression of other related proteins such as PAR-3 and Lgl-1 was unaffected. Biochemical analyses suggested that a significant fraction of aPKCλ formed a protein complex with PAR-6β and Lgl-1 in the brain lysates, which was disrupted by the aPKCλ deletion. Notably, the aPKCλ deletion mice did not show apparent cell loss/degeneration in the brain. In addition, neuronal orientation/distribution seemed to be unaffected. Thus, despite the polarity complex disruption, neuronal deletion of aPKCλ does not induce obvious cell loss or disorientation in mouse brains after cell differentiation. 相似文献
110.
Yachiyo Sasaki Satoko Ohfuji Wakaba Fukushima Akihiro Tamori Masaru Enomoto Daiki Habu Shuji Iwai Sawako Uchida-Kobayashi Hideki Fujii Susumu Shiomi Norifumi Kawada Yoshio Hirota 《PloS one》2013,8(12)