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981.
Involvement of both the V2 and V3 regions of the CCR5-tropic human immunodeficiency virus type 1 envelope in reduced sensitivity to macrophage inflammatory protein 1alpha 下载免费PDF全文
To determine whether C-C chemokines play an important role in the phenotype switch of human immunodeficiency virus (HIV) from CCR5 to CXCR4 usage during the course of an infection in vivo, macrophage inflammatory protein (MIP)-1alpha-resistant variants were isolated from CCR5-tropic (R5) HIV-1 in vitro. The selected variants displayed reduced sensitivities to MIP-1alpha (fourfold) through CCR5-expressing CD4-HeLa/long terminal repeat-beta-galactosidase (MAGI/CCR5) cells. The variants were also resistant to other natural ligands for CCR5, namely, MIP-1beta (>4-fold) and RANTES (regulated upon activation, normal T-cell expressed and secreted) (6-fold). The env sequence analyses revealed that the variants had amino acid substitutions in V2 (valine 166 to methionine) and V3 (serine 303 to glycine), although the same V3 substitution appeared in virus passaged without MIP-1alpha. A single-round replication assay using a luciferase reporter HIV-1 strain pseudotyped with mutant envelopes confirmed that mutations in both V2 and V3 were necessary to confer the reduced sensitivity to MIP-1alpha, MIP-1beta, and RANTES. However, the double mutant did not switch its chemokine receptor usage from CCR5 to CXCR4, indicating the altered recognition of CCR5 by this mutant. These results indicated that V2 combined with the V3 region of the CCR5-tropic HIV-1 envelope modulates the sensitivity of HIV-1 to C-C chemokines without altering the ability to use chemokine receptors. 相似文献
982.
Glycyrrhizin inhibits the lytic pathway of complement--possible mechanism of its anti-inflammatory effect on liver cells in viral hepatitis 总被引:10,自引:0,他引:10
Fujisawa Y Sakamoto M Matsushita M Fujita T Nishioka K 《Microbiology and immunology》2000,44(9):799-804
Glycyrrhizin, an aqueous extract of licorice root, has anti-inflammatory activity and has been used for the treatment of chronic viral hepatitis. In the present study we describe the mechanism by which glycyrrhizin inhibits complement. Glycyrrhizin inhibited the cytolytic activity of complement via the activation of both the classical and alternative pathways, while it had no effect on immune adherence, suggesting that it blocks C5 or a later stage of the complement cascade. Further analysis revealed that glycyrrhizin inhibits the lytic pathway in which the membrane attack complex (MAC) is formed. This mechanism suggests that glycyrrhizin may prevent tissue injury caused by MAC not only in chronic hepatitis but in many autoimmune and inflammatory diseases. 相似文献
983.
Genetic structure of a 2,500-year-old human population in China and its spatiotemporal changes 总被引:7,自引:0,他引:7
Wang L Oota H Saitou N Jin F Matsushita T Ueda S 《Molecular biology and evolution》2000,17(9):1396-1400
To examine temporal changes in population genetic structure, we compared the mitochondrial DNA (mtDNA) sequences of three populations that lived in the same location, Linzi, China, in different periods: 2,500 years ago (the Spring-Autumn era), 2,000 years ago (the Han era), and the present day. Two indices were used to compare the genetic differences: the frequency distributions of the radiating haplotype groups and the genetic distances among the populations. The results indicate that the genetic backgrounds of the three populations are distinct from each other. Inconsistent with the geographical distribution, the 2,500-year-old Linzi population showed greater genetic similarity to present-day European populations than to present-day east Asian populations. The 2, 000-year-old Linzi population had features that were intermediate between the present-day European/2,500-year-old Linzi populations and the present-day east Asian populations. These relationships suggest the occurrence of drastic spatiotemporal changes in the genetic structure of Chinese people during the past 2,500 years. 相似文献
984.
Matsushita K Nishina M Asakura T Kamei S Suzuki M Yabe K 《Physiological chemistry and physics and medical NMR》2000,32(1):13-19
In natural aging of spirits or wine, the dynamic structure of ethanol-water clusters changes to a smaller and more uniform state. Through experience we know that naturally aged ones have higher metabolism than the non-aged ones. Also, the same effect as natural aging can be obtained in various types of spirits or wines by the treatment for a period of time with soft ultrasonic wave (US). In this study, we compared ethanol metabolism in human subjects dosed with non-treated white wine (control = CON) and with US treated wine. Ethanol levels in human sera were followed by 400 MHz 1H-NMR spectroscopy after administration of wine doses. Experimental results indicated that ethanol metabolism was enhanced 18% in subjects when US treated wine was used rather than when non-treated (CON) was used. Other experiments using rabbits showed that a 20% ethanol-aqueous solution was absorbed 18% more rapidly by the group dosed with US wine than by the CON group. From these experimental facts, it was theorized that ethanol metabolism depends on the rapidity of ethanol absorption in the human body. And it can be concluded that US treatment brings about the same effect on spirits or wines as natural aging. 相似文献
985.
Spectroscopy on the B850 band of individual light-harvesting 2 complexes of Rhodopseudomonas acidophila. II. Exciton states of an elliptically deformed ring aggregate 下载免费PDF全文
Matsushita M Ketelaars M van Oijen AM Köhler J Aartsma TJ Schmidt J 《Biophysical journal》2001,80(3):1604-1614
Spectroscopy of individual light-harvesting 2 complexes from purple photosynthetic bacteria revealed a deformation of the circular complex into C(2) symmetry. The present work relates the geometry of the deformed aggregate to its spectroscopic properties. Different models of elliptical deformation are discussed and compared with the experimental findings. It is shown that the model with smaller interpigment distances, where the curvature of the ellipse is small, provides the best agreement with fluorescence excitation spectra of individual complexes. 相似文献
986.
Mayumi Hoshikawa Taku Aoki Hirokazu Matsushita Takahiro Karasaki Akihiro Hosoi Kosuke Odaira Nao Fujieda Yukari Kobayashi Kaori Kambara Osamu Ohara Junichi Arita Kiyoshi Hasegawa Kazuhiro Kakimi Norihiro Kokudo 《Biochemical and biophysical research communications》2018,495(2):2058-2065
To establish prognostic biomarkers and to identify potential novel therapeutic targets, we performed integrative immunomonitoring of blood and tumor in patients with resectable pancreatic cancer. Flow cytometry (FC) was employed for phenotyping immune cells, multiplex bead assays for plasma cytokine and chemokine determination, and RNA-Seq for the analysis of gene expression in the tumor. Nineteen pancreatic cancer patients were stratified into those with longer or shorter than median recurrence-free survival after surgery (median, 426 days). There were no significant differences between the two groups for clinical parameters including age, sex, surgical procedure, stage, or postoperative adjuvant therapy. However, we found that the percentages of NK cells as assessed by FC in peripheral blood mononuclear cells were higher in patients with late recurrence (P?=?.037). RNA-Seq data indicated no differences in the amount of immune cells or stromal cells between the two groups, although NK cells in the tumor did tend to be higher in patients with late recurrence (P?=?.058). Type I and II IFN signatures were enriched in late-recurring tumors (FDR q-value <0.001), while genes related to KRAS signaling and the epithelial mesenchymal transition (EMT) were enriched in early recurrence. We conclude that tumor-intrinsic properties of metastasis and recurrence influence prognosis, whereas NK cells that might contribute to prevent metastasis are associated with longer recurrence-free survival. Therefore, enhancement of NK cell activity and inhibition of the EMT and KRAS signaling might represent appropriate therapeutic targets following surgical resection of pancreatic cancer. 相似文献
987.
Yakushi Toshiharu Fukunari Seiya Kodama Tomohiro Matsutani Minenosuke Nina Shun Kataoka Naoya Theeragool Gunjana Matsushita Kazunobu 《Applied microbiology and biotechnology》2018,102(10):4549-4561
Applied Microbiology and Biotechnology - Acetic acid fermentation is widely considered a consequence of ethanol oxidation by two membrane-bound enzymes—alcohol dehydrogenase and aldehyde... 相似文献
988.
Sexual and temporal variations in floral scent in the subdioecious shrub Eurya japonica Thunb 下载免费PDF全文
Hui Wang Peiming Zheng Dan Aoki Takashi Miyake Sachie Yagami Yasuyuki Matsushita Kazuhiko Fukushima Michiko Nakagawa 《Ecology and evolution》2018,8(16):8266-8272
In many flowering plants, floral scents are a significant trait for visitors, playing an important role in attracting pollinators and/or detracting herbivores. The evolution of flowering plants from hermaphroditism to dioecy is often accompanied by sexual dimorphism in floral scent. In this study, floral scents emitted by different sexual morphs of the subdioecious shrub Eurya japonica Thunb. were collected using a dynamic headspace method, and sexual and temporal variations were evaluated by gas chromatography–mass spectrometry (GC–MS). Two volatiles, α‐pinene and linalool, were identified as the major components of floral scents in females, hermaphrodites, and males. The males emit higher amounts of floral scents, particularly α‐pinene, compared to females or hermaphrodites. Floral scents emitted by males generally decrease as flowers enter senescence, whereas those from females or hermaphrodites do not significantly differ. Intraspecific variations in floral scents of subdioecious species provided by this study would contribute to better understanding of sexual dimorphism in floral scent. 相似文献
989.
990.
Minoru Ameyama Emiko Shinagawa Kazunobu Matsushita Osao Adachi 《Bioscience, biotechnology, and biochemistry》2013,77(11):2909-2911
Yeast alcohol dehydrogenase (ADH), diaphorase (DI) and NAD were co-immobilized on Sepharose that had been repeatedly modified with hexamethylenediamine and glutaraldehyde. The activity and re-usability of the gel were investigated with changing the immobilization conditions of the enzymes and the reaction conditions of the glutaraldehyde used in the modification. The results suggested that the immobilization temperature and the immobilization time of the enzymes mainly had an effect on the stability and activity, respectively. The degree of polymerization of the glutaraldehyde affected both the activity and the re-usability, and A235/A2S0 was used as an index of the degree of polymerization. The optimum conditions were as follows: a temperature and reaction time in the immobilization of the enzymes of 20°C and 7 hr, respectively, and a degree of polymerization of the glutaraldehyde used in the modification of A235/A2S0 = 20. The gel prepared under these optimum conditions was applied to a flow injection analytical system for ethanol. A good linear relationship between the concentration and the response was observed in the range of 20 ~ 80 mm, suggesting that the gel would be applicable to ethanol analysis. 相似文献