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101.
Kubo Y Tominaga C Yoshii H Kamiyama H Mitani C Amanuma H Yamamoto N 《Archives of virology》2007,152(12):2169-2182
Summary The C-terminal R peptide of ecotropic murine leukemia virus (MLV) envelope protein (Env) negatively controls membrane fusion
activity. The R peptide cleavage during virion maturation activates its fusogenicity and is required for viral entry. We analyzed
fusogenicity and transduction efficiency of mutant Env proteins of ecotropic, amphotropic, polytropic, and xenotropic MLVs.
As the result, we found that the hydrophobic amino acid residues around the R peptide cleavage site are important for membrane
fusion inhibition by the R peptide. In addition, we found that Env complexes with R peptide-truncated and -containing Env
proteins have lower fusogenicity and transduction efficiency than those with the R-peptide-truncated Env alone, suggesting
that efficient R peptide cleavage is required for efficient MLV vector transduction. The role of R peptide cleavage in amphotropic,
polytropic, and xenotropic MLV infection has not been investigated. We found in this study that the R peptide cleavage is
required for amphotropic, xenotropic, and polytropic MLV vector transduction, like with ecotropic MLV. The R-peptide-truncated
Env proteins of the xenotropic and polytropic MLVs, however, had much lower fusogenicity than those of the ecotropic and amphotropic
MLVs. These results provide valuable information for construction of efficient MLV vectors and for understanding the retroviral
entry mechanism. 相似文献
102.
Matsuura K Tanaka Y Takagi K Hiramatsu K Kani S Gotoh T Wakimoto Y Joh T Mizokami M 《Rinsho byori. The Japanese journal of clinical pathology》2007,55(11):983-988
The Abbott Real Time HCV assay (lower limit of detection 12 IU/ml) was developed as a highly sensitive HCV RNA quantitative assay using real-time detection PCR(RTD-PCR). We assessed whether the new assay more effectively predicts sustained virological response (SVR) than conventional PCR (PCR) in 38 chronic hepatitis patients infected with HCV genotype 1b and treated with pegylated interferon alpha2b plus ribavirin. Sixteen patients reached SVR, 10 patients relapsed, 9 patients did not respond, 3 patients discontinued treatment. Positive predictive value (PPV) for SVR of undetectable HCV RNA at W4, 8, 12 by RTD-PCR and PCR was (100% vs. 100% at W4), (100% vs. 100% at W8), (83.3% vs. 72.7% at W12). HCV RNA undetectable at W12 had a higher PPV for SVR when measured by RTD-PCR than by conventional PCR. 相似文献
103.
Kurabayashi M Tajima K 《The New England journal of medicine》2007,356(5):526; discussion 526-526; discussion 527
104.
Taguchi Kumiko Bessho Nanami Hida Mari Narimatsu Haruka Matsumoto Takayuki Kobayashi Tsuneo 《Naunyn-Schmiedeberg's archives of pharmacology》2018,391(10):1075-1083
Naunyn-Schmiedeberg's Archives of Pharmacology - Abnormal G protein-coupled receptor kinase 2 (GRK2) accumulation has a crucial role in the development of insulin resistance and diabetes.... 相似文献
105.
Morita I Nakagaki H Yoshii S Tsuboi S Hayashizaki J Igo J Mizuno K Sheiham A 《Journal of clinical periodontology》2007,34(11):952-956
AIM: The objective was to assess whether there was a social gradient in periodontal status by job classification in Japanese male workers. MATERIAL AND METHODS: Study participants were 15,803 Japanese male workers aged 20-69 years. There were seven groups classified by jobs. Oral examinations were conducted using community periodontal index (CPI). RESULTS: The percentages of sextants with a CPI score of 3 or 4 of professionals were significantly lower than for other job classes. The gradient also existed for the percentage of sextants with CPI score 4. After adjusting for age, a history of diabetes mellitus and smoking status, those lower on the gradient, namely, drivers, service occupations, salespersons and managers were 2.0, 1.5, 1.4 and 1.4, times, respectively more likely to have one or more sextants with CPI score 3 or 4 compared with professionals. Odds ratios of having more than one or more sextants with CPI score 4 after adjusting for age, clinical history of diabetes mellitus and smoking status for drivers, service occupations, salespersons and managers were 2.1, 1.5, 1.5 and 1.2, respectively, compared with professionals. CONCLUSIONS: There was a gradient in periodontal status by job classification. Professional and office workers had better periodontal status than salespersons, service occupations and drivers. 相似文献
106.
Yamashita Takehiro Terasaki Hiroto Tanaka Minoru Nakao Kumiko Sakamoto Taiji 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(8):1779-1785
Graefe's Archive for Clinical and Experimental Ophthalmology - To determine the relationship between the peripapillary choroidal thickness (ppCT) and the degree and distribution of the... 相似文献
107.
108.
Kumiko Matsuzaki Yasushi Shimada Yasuo Shinno Serina Ono Kozo Yamaji Naoko Ohara Alireza Sadr Yasunori Sumi Junji Tagami Masahiro Yoshiyama 《Materials》2021,14(8)
The purpose of this study was to evaluate the mechanism of action and the inhibiting effects of two types of desensitizers against dentin demineralization using pre-demineralized hypersensitivity tooth model in vitro. In this study, we confirmed that a hypersensitivity tooth model from our preliminary experiment could be prepared by immersing dentin discs in an acetic acid-based solution with pH 5.0 for three days. Dentin discs with three days of demineralization were prepared and applied by one of the desensitizers containing calcium fluoro-alumino-silicate glass (Nanoseal, NS) or fluoro-zinc-silicate glass (Caredyne Shield, CS), followed by an additional three days of demineralization. Dentin discs for three days of demineralization (de3) and six days of demineralization (de6) without the desensitizers were also prepared. The dentin discs after the experimental protocol were scanned using swept-source optical coherence tomography (SS-OCT) to image the cross-sectional (2D) view of the samples and evaluate the SS-OCT signal. The signal intensity profiles of SS-OCT from the region of interest of 300, 500, and 700 µm in depth were obtained to calculate the integrated signal intensity and signal attenuation coefficient. The morphological differences and remaining chemical elements of the dentin discs were also analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy. SS-OCT images of CS and NS groups showed no obvious differences between the groups. However, SS-OCT signal profiles for both the CS and NS groups showed smaller attenuation coefficients and larger integrated signal intensities than those of the de6 group. Reactional deposits of the desensitizers even after the additional three days of demineralization were observed on the dentin surface in NS group, whereas remnants containing Zn were detected within the dentinal tubules in CS group. Consequently, both CS and NS groups showed inhibition effects against the additional three days of demineralization in this study. Our findings demonstrate that SS-OCT signal analysis can be used to monitor the dentin demineralization and inhibition effects of desensitizers against dentin demineralization in vitro. 相似文献
109.
Kumiko Yoshihara Noriyuki Nagaoka Aya Umeno Akinari Sonoda Hideki Obika Yasuhiro Yoshida Bart Van Meerbeek Yoji Makita 《Materials》2021,14(6)
Several dental materials contain silver for antibacterial effect, however the effect is relatively low. The reason for the lower antibacterial efficacy of silver is considered to be the fact that silver ions bind to chloride ions in saliva. To develop new effective silver antibacterial agents that can be useful in the mouth, we synthesized two novel amino acid (methionine or histidine)–silver complexes (Met or His–Ag) loaded with montmorillonite (Mont) and analyzed their antibacterial efficacy. At first the complexes were characterized using nuclear magnetic resonance (NMR), and amino acid–Ag complex-loaded Mont (amino acid–Ag–Mont) were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The antibacterial efficacy of these materials in dental acrylic resin was then investigated by bacterial growth measurement using a spectrophotometer. As controls, commercially available silver-loaded zeolite and silver-zirconium phosphate were also tested. Dental acrylic resin incorporating His–Ag–Mont strongly inhibited Streptococcus mutans growth. This was explained by the fact that His-Ag complex revealed the highest amounts of silver ions in the presence of chloride. The structure of the amino acid–Ag complexes affected the silver ion presence in chloride and the antibacterial efficacy. His–Ag–Mont might be used as antibacterial agents for dental materials. 相似文献
110.
OBJECTIVE: To clarify the signaling mechanism of human myeloid differentiation by hematopoietic growth factors and cytokines, we investigated the role of extracellular signal-regulated kinase (ERK) during the differentiation of human monoblastic U937 cells stimulated by granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF). MATERIALS AND METHODS: Myeloid differentiation was evaluated by morphology, function (respiratory burst activity), and cell surface expression of adhesion molecule (CD11b), and activation of ERK and/or p38 was determined by Western blotting and/or in vitro kinase assay. Inhibition of the ERK pathway was performed using PD98059, a specific inhibitor of this pathway. RESULTS: U937 cells were induced to be differentiated by the combination of GM-CSF and TNF, but only minimally by either cytokine alone. Transient phosphorylation and activation of ERK was induced by both GM-CSF alone and combination of the two cytokines, whereas sustained phosphorylation and activation was induced only by the combination. In addition, PD98059, a specific inhibitor of ERK pathway, almost completely abolished this prolonged phosphorylation of ERK and completely blocked differentiation. In contrast, both TNF alone and cytokine combination equivalently phosphorylated p38 in U937 cells, which was dissociated from differentiation, and a specific inhibitor of p38 (SB203580) did not inhibit differentiation. CONCLUSIONS: The results indicate potential roles of sustained activation of ERK but not of p38 in the signaling pathways for human myeloid differentiation in U937 cells synergistically stimulated by the two physiologic cytokines GM-CSF and TNF. 相似文献