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81.
Patients with atopic dermatitis (AD) have superficial skin colonization with Staphylococcus aureus and an increased number of T helper (Th)2 cells in their peripheral blood. The purpose of this study was to clarify the involvement of interleukin (IL)‐10 secretion from Langerhans cells (LCs) in staphylococcal peptidoglycan (PEG)‐induced Th2 immune responses in mice. Mice were primed with LCs pulsed with PEG (or LPS) and ovalbumin (OVA) and then given a booster OVA injection 2 days later in the hind footpad. Five days after the OVA injection, cytokine responses in the draining popliteal lymph nodes were investigated by RT‐PCR and ELISA. Production of both IL‐10 and IL‐12 by cultured LCs was detected by ELISA. Administration of PEG‐ or LPS‐stimulated LCs into the hind footpads of the mice induced Th2‐prone and Th1‐prone immune responses, respectively, as represented by expression of IL‐4 and interferon ‐γ . In vitro experiments showed that PEG induced greater production of IL‐12 p40 from LCs than did LPS, whereas LPS induced greater production of IL‐12 p70 from LCs than did PEG. Furthermore, it was found that PEG‐stimulated LCs induced greater production of IL‐10 than did LPS‐stimulated LCs, and that neutralization of IL‐10 augmented IL‐12 p70 production and inhibited Th2 development by PEG‐stimulated LCs. These results suggest that PEG can induce Th2 development through down‐regulation of IL‐12 p70 production by LCs in an IL‐10 production‐dependent manner and would explain the role of S. aureus colonization in patients with AD. 相似文献
82.
Hadhemi Kaddour Yosra Hamdi David Vaudry Magalie Basille Laurence Desrues Jérôme Leprince Hélène Castel Hubert Vaudry Marie‐Christine Tonon Mohamed Amri Olfa Masmoudi‐Kouki 《Journal of neurochemistry》2013,125(4):620-633
Oxidative stress, induced by various neurodegenerative diseases, initiates a cascade of events leading to apoptosis, and thus plays a critical role in neuronal injury. In this study, we have investigated the potential neuroprotective effect of the octadecaneuropeptide (ODN) on 6‐hydroxydopamine (6‐OHDA)‐induced oxidative stress and apoptosis in cerebellar granule neurons (CGN). ODN, which is produced by astrocytes, is an endogenous ligand for both central‐type benzodiazepine receptors (CBR) and a metabotropic receptor. Incubation of neurons with subnanomolar concentrations of ODN (10?18 to 10?12 M) inhibited 6‐OHDA‐evoked cell death in a concentration‐dependent manner. The effect of ODN on neuronal survival was abrogated by the metabotropic receptor antagonist, cyclo1–8[DLeu5]OP, but not by a CBR antagonist. ODN stimulated polyphosphoinositide turnover and ERK phosphorylation in CGN. The protective effect of ODN against 6‐OHDA toxicity involved the phospholipase C/ERK MAPK transduction cascade. 6‐OHDA treatment induced an accumulation of reactive oxygen species, an increase of the expression of the pro‐apoptotic gene Bax, a drop of the mitochondrial membrane potential and a stimulation of caspase‐3 activity. Exposure of 6‐OHDA‐treated cells to ODN blocked all the deleterious effects of the toxin. Taken together, these data demonstrate for the first time that ODN is a neuroprotective agent that prevents 6‐OHDA‐induced oxidative stress and apoptotic cell death. 相似文献
83.
Masamitsu Konno Atsushi Hamabe Shinichiro Hasegawa Hisataka Ogawa Takahito Fukusumi Shimpei Nishikawa Katsuya Ohta Yoshihiro Kano Miyuki Ozaki Yuko Noguchi Daisuke Sakai Toshihiro Kudoh Koichi Kawamoto Hidetoshi Eguchi Taroh Satoh Masahiro Tanemura Hiroaki Nagano Yuichiro Doki Masaki Mori Hideshi Ishii 《Development, growth & differentiation》2013,55(3):309-318
Adipose tissue‐derived mesenchymal stem cells (ADSCs) are multipotent and can differentiate into various cell types, including osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β‐cells, and hepatocytes. Compared with the extraction of other stem cells such as bone marrow‐derived mesenchymal stem cells (BMSCs), that of ADSCs requires minimally invasive techniques. In the field of regenerative medicine, the use of autologous cells is preferable to embryonic stem cells or induced pluripotent stem cells. Therefore, ADSCs are a useful resource for drug screening and regenerative medicine. Here we present the methods and mechanisms underlying the induction of multilineage cells from ADSCs. 相似文献
84.
Ahmed Abdelmoniem Mousa Shinuo Cao Gabriel Oluga Aboge Mohamad Alaa Terkawi Ahmed El Kirdasy Akram Salama Mabrouk Attia Mahmoud Aboulaila Mo Zhou Ketsarin Kamyingkird Paul Franck Adjou Moumouni Tatsunori Masatani Sami Ahmed Abd El Aziz Waheed Mohammed Moussa Bayin Chahan Shinya Fukumoto Yoshifumi Nishikawa Salah Sayed El Ballal Xuenan Xuan 《Experimental parasitology》2013
Identification and molecular characterization of Babesia gibsoni proteins with potential antigenic properties are crucial for the development and validation of the serodiagnostic method. In this study, we isolated a cDNA clone encoding a novel B. gibsoni 76-kDa protein by immunoscreening of the parasite cDNA library. Computer analysis revealed that the protein presents a glutamic acid-rich region in the C-terminal. Therefore, the protein was designated as B. gibsoni glutamic acid-rich protein (BgGARP). A BLASTp analysis of a translated BgGARP polypeptide demonstrated that the peptide shared a significant homology with a 200-kDa protein of Babesia bigemina and Babesia bovis. A truncated BgGARP cDNA (BgGARPt) encoding a predicted 13-kDa peptide was expressed in Escherichia coli (E. coli), and mouse antisera against the recombinant protein were used to characterize a corresponding native protein. The antiserum against recombinant BgGARPt (rBgGARPt) recognized a 140-kDa protein in the lysate of infected erythrocytes, which was detectable in the cytoplasm of the parasites by confocal microscopic observation. In addition, the specificity and sensitivity of enzyme-linked immunosorbent assay (ELISA) with rBgGARPt were evaluated using B. gibsoni-infected dog sera and specific pathogen-free (SPF) dog sera. Moreover, 107 serum samples from dogs clinically diagnosed with babesiosis were examined using ELISA with rBgGARPt. The results showed that 86 (80.4%) samples were positive by rBgGARPt-ELISA, which was comparable to IFAT and PCR as reference test. Taken together, these results demonstrate that BgGARP is a suitable serodiagnostic antigen for detecting antibodies against B. gibsoni in dogs. 相似文献
85.
Kentaro Takai Yasunao Inoue Yasuko Konishi Atsushi Suwa Yoshiharu Uruno Harumi Matsuda Tomokazu Nakako Mutsuko Sakai Hiroyuki Nishikawa Gakuji Hashimoto Takeshi Enomoto Atsushi Kitamura Yasuaki Uematsu Akihiko Kiyoshi Takaaki Sumiyoshi 《Bioorganic & medicinal chemistry letters》2013,23(16):4644-4647
We designed and synthesized N-substituted 8-azatetrahydroquinolone derivatives as selective M1 and M4 muscarinic acetylcholine receptors agonists. Optimization of selected derivatives led to the discovery of compound 7 as a highly potent M1 and M4 agonist with weak hERG inhibition. Oral administration of compound 7 improved psychosis-like behavior in rats. 相似文献
86.
Eriko Kudo Manabu Taura Kouki Matsuda Masako Shimamoto Ryusho Kariya Hiroki Goto Shinichiro Hattori Shinya Kimura Seiji Okada 《Bioorganic & medicinal chemistry letters》2013,23(3):606-609
The anti-HIV-1 activity of GUT-70, a natural product derived from the stem bark of Chlophyllum brasiliense, was evaluated. GUT-70 inhibited HIV-1 replication in both acutely and chronically infected cells through suppression of NF-κB. Our results strengthen the idea that NF-κB pathway is one of the potential targets to control HIV-1 replication and that GUT-70 could serve as a lead compound to develop novel therapeutic agents against HIV-1 infection. 相似文献
87.
Zhe Nie Victoria Feher Srinivasa Natala Christopher McBride Andre Kiryanov Benjamin Jones Betty Lam Yan Liu Stephen Kaldor Jeffrey Stafford Kouki Hikami Noriko Uchiyama Tomohiro Kawamoto Yuichi Hikichi Shin-ichi Matsumoto Nobuyuki Amano Lilly Zhang David Hosfield Takashi Ichikawa 《Bioorganic & medicinal chemistry letters》2013,23(12):3662-3666
Using structure-based drug design, we identified and optimized a novel series of pyrimidodiazepinone PLK1 inhibitors resulting in the selection of the development candidate TAK-960. TAK-960 is currently undergoing Phase I evaluation in adult patients with advanced solid malignancies. 相似文献
88.
Yasutoyo Nagai Tetsusaburo Nishikawa 《Bioscience, biotechnology, and biochemistry》2013,77(4):575-584
Chicken feather powder was solubilized by Schweitzer’s reagent with shaking in the presence of air and the soluble feather keratin was prepared by dialyzing this extract against running water. Cystine residues in the starting feather keratin was converted to cysteic acid residues in the solubilized derivatives by air oxygen. Copper was bound fairly tightly to the solubilized protein and this copper-protein complex was separated into four fractions by CM- and DEAE-cellulose column chromatography. Each fraction had varied amount of bound copper, having a broad distribution of the molecular weight between 10,000 and 60,000 Sephadex column chromatographically. Although the amino acid composition of all separated feather keratin fractions were quite similar, the different electrophoretic patterns were observed among them by DISC electrophoresis. 相似文献
89.
90.