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131.
Gursel M Gursel I Mostowski HS Klinman DM 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(3):1575-1580
Unmethylated CpG motifs are present at high frequency in bacterial DNA. They provide a danger signal to the mammalian immune system that triggers a protective immune response characterized by the production of Th1 and proinflammatory cytokines and chemokines. Although the recognition of CpG DNA by B cells and plasmacytoid dendritic cells is mediated by TLR 9, these cell types differ in their ability to bind and respond to structurally distinct classes of CpG oligonucleotides. This work establishes that CXCL16, a membrane-bound scavenger receptor, influences the uptake, subcellular localization, and cytokine profile induced by D oligonucleotides. This is the first example of a surface receptor modifying the cellular specificity and nature of the immune response mediated by an intracellular TLR. 相似文献
132.
To estimate the evolutionary history of the mustard family (Brassicaceae or Cruciferae), we sampled 113 species, representing 101 of the roughly 350 genera and 17 of the 19 tribes of the family, for the chloroplast gene ndhF. The included accessions increase the number of genera sampled over previous phylogenetic studies by four-fold. Using parsimony, likelihood, and Bayesian methods, we reconstructed the phylogeny of the gene and used the Shimodaira-Hasegawa test (S-H test) to compare the phylogenetic results with the most recent tribal classification for the family. The resultant phylogeny allowed a critical assessment of variations in fruit morphology and seed anatomy, upon which the current classification is based. We also used the S-H test to examine the utility of trichome branching patterns for describing monophyletic groups in the ndhF phylogeny. Our phylogenetic results indicate that 97 of 114 ingroup accessions fall into one of 21 strongly supported clades. Some of these clades can themselves be grouped into strongly to moderately supported monophyletic groups. One of these lineages is a novel grouping overlooked in previous phylogenetic studies. Results comparing 30 different scenarios of evolution by the S-H test indicate that five of 12 tribes represented by two or more genera in the study are clearly polyphyletic, although a few tribes are not sampled well enough to establish para- or polyphyly. In addition, branched trichomes likely evolved independently several times in the Brassicaceae, although malpighiaceous and stellate trichomes may each have a single origin. 相似文献
133.
Yurekli AI Ozkan M Kalkan T Saybasili H Tuncel H Atukeren P Gumustas K Seker S 《Electromagnetic biology and medicine》2006,25(3):177-188
The ever increasing use of cellular phones and the increasing number of associated base stations are becoming a widespread source of nonionizing electromagnetic radiation. Some biological effects are likely to occur even at low-level EM fields. In this study, a gigahertz transverse electromagnetic (GTEM) cell was used as an exposure environment for plane wave conditions of far-field free space EM field propagation at the GSM base transceiver station (BTS) frequency of 945 MHz, and effects on oxidative stress in rats were investigated. When EM fields at a power density of 3.67 W/m2 (specific absorption rate = 11.3 mW/kg), which is well below current exposure limits, were applied, MDA (malondialdehyde) level was found to increase and GSH (reduced glutathione) concentration was found to decrease significantly (p < 0.0001). Additionally, there was a less significant (p = 0.0190) increase in SOD (superoxide dismutase) activity under EM exposure. 相似文献
134.
Ciftci IH Cetinkaya Z Atambay M Kiyildi N Aycan OM Daldal N 《The Korean journal of parasitology》2006,44(3):259-264
House dust mites play an important role in the pathogenesis of allergic diseases. Many factors may influence mite growth. The presence of mites is related to mean temperature and humidity as well as altitude. The aim of this study was to analyze the mite fauna in 5 regions of western Anatolia, Turkey, that have similar climatic properties with low mean temperature and humidity, but differ in altitude. During the period October-November 2004, house dust was collected from 290 homes in 5 different cities. House dust mites were isolated in 67 (23.1%) of 290 samples. The family Pyroglyphidae (Astigmata) was present in all positive samples. This study suggests that the selected western Anatolian regions that share similar environmental conditions host similar dust mite populations. 相似文献
135.
Guven Ozdemir Baris Pazarbasi Ali Kocyigit Esra Ersoy Omeroglu Ihsan Yasa Ismail Karaboz 《World journal of microbiology & biotechnology》2008,24(8):1375-1381
The present study deals with the decolorization of Acid Black 210 by a bioluminescent bacterium, Vibrio harveyi TEMS1, isolated from coastal seawater of Izmir Bay, Turkey. Maximum rate of decolorization of Acid Black 210 was observed
when Luria Bertani medium was used. Decolorization of Acid Black 210 was 38.9% and 93.9% at 24 h under shaking and static
conditions, respectively. The optimum dye-decolorizing activity of the culture was obtained at 100 ppm initial dye concentration
and incubation temperature of 20°C. Vibrio harveyi TEMS1 was also tested for its ability to decolorize four azo dyes (Acid Black 24, Acid Blue 7, Acid Green 20, Acid Yellow
36) in addition to Acid Black 210. 相似文献
136.
Four cycloartane glycosides, 3-O-[α-l-arabinopyranosyl-(1 → 2)-β-d-xylopyranosyl]-3β,6α,16β,23α,25-pentahydroxy-20(R),24(S)-epoxycycloartane (1), 3-O-[α-l-arabinopyranosyl-(1 → 2)-β-d-xylopyranosyl]-16-O-hydroxyacetoxy-23-O-acetoxy-3β,6α,25-trihydroxy-20(R),24(S)-epoxycycloartane (2), 3-O-[α-l-arabinopyranosyl-(1 → 2)-β-d-xylopyranosyl]-3β,6α,23α,25-tetrahydroxy-20(R),24(R)-16β,24;20,24-diepoxycycloartane (3), 3-O-[α-l-arabinopyranosyl-(1 → 2)-β-d-xylopyranosyl]-25-O-β-d-glucopyranosyl-3β,6α,16β,25-tetrahydroxy-20(R),24(S)-epoxycycloartane (4), along with three known cycloartane glycosides were isolated from the MeOH extract of the roots of Astragalus campylosema ssp. campylosema. Their structures were established by the extensive use of 1D- and 2D-NMR experiments along with ESIMS and HRMS analysis. The occurrence of the hydroxyl function at position 23 (1-2) and of the ketalic function at C-24 (3) are very unusual findings in the cycloartane class. 相似文献
137.
Ihsan A. Al‐Shehbaz 《Nordic Journal of Botany》2012,30(6):737-738
Cardamine guatemalensis Al‐Shehbaz is described from Zacapa, Guatemala. Its features such as the perennial, scapose, rhizomatous habit and simple leaves are very rare among North American Brassicaceae. The distinguishing characters from other species of Cardamine are discussed. 相似文献
138.
139.
Muhammad Nisar Shafiq Ahmad Tariq Inamullah Khan Marwat Muhammad Raza Shah Ihsan Ali Khan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):224-229
The antibacterial, antifungal, acute cytotoxicity, phytotoxicity and insecticidal profile of the crude extract and various fractions of Indigofera gerardiana have been studied. Six bacterial and fungal strains were used, of which Samonella typhi and Microsporum canis were the most susceptible strains with MICs 0.37 mg/mL and 0.09 mg/mL, respectively. The crude extract and the fractions showed low insecticidal activity against Sitophilus oryzae, Rhyzopertha dominica and Callosbruchus analis but no activity against Tribolium castaneum. The brine shrimp lethality assay showed absence of any measurable cytotoxicity of the crude extract and fractions, showing a good safety profile at a preliminary level. All the fractions except crude extract revealed profound and highly significant herbicidal activity against Lemna minor at the concentration of 1000 μg/mL. Indigofera gerardiana was shown by in-vitro assays to be a potential source for natural antifungal, antibacterial and herbicidal agents. 相似文献
140.
Adam M Corrigan Roshan L Shrestha Ihsan Zulkipli Noriko Hiroi Yingjun Liu Naoka Tamura Bing Yang Jessica Patel Akira Funahashi Athene Donald Viji M Draviam 《Cell cycle (Georgetown, Tex.)》2013,12(16):2643-2655
Spindle orientation defines the plane of cell division and, thereby, the spatial position of all daughter cells. Here, we develop a live cell microscopy-based methodology to extract spindle movements in human epithelial cell lines and study how spindles are brought to a pre-defined orientation. We show that spindles undergo two distinct regimes of movements. Spindles are first actively rotated toward the cells’ long-axis and then maintained along this pre-defined axis. By quantifying spindle movements in cells depleted of LGN, we show that the first regime of rotational movements requires LGN that recruits cortical dynein. In contrast, the second regime of movements that maintains spindle orientation does not require LGN, but is sensitive to 2ME2 that suppresses microtubule dynamics. Our study sheds first insight into spatially defined spindle movement regimes in human cells, and supports the presence of LGN and dynein independent cortical anchors for astral microtubules. 相似文献