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101.
Low frequency magnetic fields have previously been shown to affect cell functions. In this article, the effects of 20 mT, 50 Hz sinusoidal magnetic field on cell proliferation, ion concentration, and osmolarity in two human cancer cell lines (HL-60 and SK-Hep-1) were investigated. Inhibition of cell growth was observed. On the other hand, the exposure also increased the Na+, K+ ion concentration and osmolarity in cell supernatant compared to the control group. To our knowledge, this is the first study on cancer cells where magnetic fields affect osmolarity in cell supernatant. In addition, a model of cells exposed to the oscillating magnetic field is described as well as the characteristics of ions in and out of cells. The experimental data appears to be consistent with the theoretical analysis. The results are also discussed in terms of the relationships among cell growth, ion concentration, and osmolarity. Magnetic field inhibitions of cell growth in vitro may relate to changes in cell ion concentration and osmolarity. 相似文献
102.
A new acylated secoiridoidal glucoside, named gentiorigenoside A (1 ), was isolated from the root of Gentiana rigescens (Gentianaceae) , together with eight known compounds, gentiopicroside ( 2) , 6′- O-β- D-glucopyranosyl gentiopicroside (3) , loganic acid (4 ) , 6′- O-β- D-glucopyranosyl loganic acid ( 5), sweroside ( 6 ), 2′-( o, m-dihydoxybenzyl) -sweroside (7), swertiamarin (8) and secologanoside (9) . heir structures were elucidated on the basis of detailed spectroscopic analysis. Iridoidal glucosides 3, 5 and 9 were isolated for the first time from the title plant. 相似文献
103.
Ding Haixia Zhang Jingsong Jiang Lei Dong Hairong Wang Jun Xiao Hang Chen Weixian 《Cell biochemistry and biophysics》2011,59(1):39-47
Extracellular domains of the transmembrane glycoprotein, neuropilin-1 (Np1), specifically bind an array of factors and co-receptors
including class-3 semaphorins (Sema3a), vascular endothelial growth factor (VEGF), hepatocyte growth factor, platelet-derived
growth factor BB, transforming growth factor-β 1 (TGF-β1), and fibroblast growth factor2 (FGF2). Np1 may have a role in immune
response, tumor cell growth, and angiogenesis, but its relative expression in comparison to its co-primary receptors, VEGF
and Sema3a, is not known. In this study we determined the mRNA expression of Np1 and its co-receptors, VEGF and Sema3a, and
the ratio of VEGF/Sema3a in different human and rodent cell lines. Expression of Np1, VEGF and Sema3a is very low in cells
derived from normal tissues, but these proteins are highly expressed in tumor-derived cells. Furthermore, the ratio of VEGF/Sema3a
is highly variable in different tumor cells. The elevated mRNA expression of Np1 and its putative receptors in tumor cells
suggests a role for these proteins in tumor cell migration and angiogenesis. As different tumor cells exhibit varying VEGF/Sema3a
ratios, it appears that cancer cells show differential response to angiogenic factors. These results bring to light the individual
variation among the cancer-related genes, Np1, VEGF, and Sema3a, and provide an important impetus for the possible personalized
therapeutic approaches for cancer patients. 相似文献
104.
To determine the species of the yeast-like symbionts (YLS) in the brown planthoppers (BPH), Nilaparvata lugens, YLS were first isolated and purified by ultracentrifugation from the fat bodies of BPH, and then 18S rDNA and internal transcribed
spacer (ITS)–5.8S rDNA sequences of YLS were amplified with the different general primers for fungi. The results showed that
the two different 18S and ITS–5.8S rDNA sequences of YLS were obtained. One 2291-bp DNA sequence, which contained 18S and
ITS–5.8S rDNA, showed the high similarity to Cryptococcus and was named Cryp-Like symbiotes. Another 1248-bp DNA sequence, which contained a part of 18S and ITS–5.8S rDNA, showed the high similarity
to Pichia guilliermondii and was named Pichia-Like symbiotes. It was further proved that Cryp- and Pichia-Like symbiotes existed in BPH through nested PCR with specific primers for two symbiotes and in situ hybridization analysis
using digoxigenin-labeled probes. Our results showed that BPH harbored more than one species of eukaryotic YLS, which suggested
that diversity of fungal endosymbiotes may be occurred in planthoppers, just like bacterial endosymbiotes. 相似文献
105.
Jigon Han Leonid N. Ten Dong Hoon Lee In-Kyu Kang Hee-Young Jung 《Antonie van Leeuwenhoek》2018,111(10):1815-1823
A bacterial isolate was recovered from a soil sample collected in Jeollabuk-do Province, South Korea, and subjected to polyphasic taxonomic assessment. Cells of the isolate, designated strain S1-2-1-2-1T, were observed to be rod-shaped, pink in color, and Gram-stain negative. The strain was able to grow at temperature range from 10 to 30 °C, with an optimum of 25 °C, and growth occurred at pH 6–8. Comparative 16S rRNA gene sequence analysis showed that strain S1-2-1-2-1T belongs to the genus Hymenobacter, with closely related type strains being Hymenobacter daeguensis 16F3Y-2T (95.8% similarity), Hymenobacter rubidus DG7BT (95.8%), Hymenobacter soli PBT (95.7%), Hymenobacter terrenus MIMtkLc17T (95.6%), Hymenobacter terrae DG7AT (95.3%), and Hymenobacter saemangeumensis GSR0100T (95.2%). The genomic DNA G+C content of strain S1-2-1-2-1T was 63.0 mol%. The main polar lipid of this strain was phosphatidylethanolamine, the predominant respiratory quinone was menaquinone-7, and the major fatty acids were C15:0 iso (27.3%), summed feature 3 (C16:1 ω7c/C16:1 ω6c) (16.5%), C15:0 anteiso (15.3%), and C16:0 (14.7%), supporting the affiliation of this strain with the genus Hymenobacter. The results of this polyphasic analysis allowed for the genotypic and phenotypic differentiation of strain S1-2-1-2-1T from recognized Hymenobacter species. On the basis of its phenotypic properties, genotypic distinctiveness, and chemotaxonomic features, strain S1-2-1-2-1T is considered to represent a novel species of the genus Hymenobacter, for which the name Hymenobacter agri sp. nov. is proposed. The type strain is S1-2-1-2-1T (=KCTC 52739T?=?JCM 32194T). 相似文献
106.
The Synergistic Effect of Cation and Anion of an Ionic Liquid Additive for Lithium Metal Anodes 下载免费PDF全文
Lithium metal anodes are steadily gaining more attention, as their superior specific capacities and low redox voltage can significantly increase the energy density of rechargeable batteries far beyond those of current Li‐ion batteries. Nonetheless, the relevant technology is still in a premature research stage mainly due to the uncontrolled growth of Li dendrites that ceaselessly cause unwanted side reactions with electrolyte. In order to circumvent this shortcoming, herein, an ionic liquid additive, namely, 1‐dodecyl‐1‐methylpyrrolidinium (Pyr1(12)+) bis(fluorosulfonyl)imide (FSI?), for conventional electrolyte solutions is reported. The Pyr1(12)+ cation with a long aliphatic chain mitigates dendrite growth via the combined effects of electrostatic shielding and lithiophobicity, whereas the FSI? anion can induce the formation of rigid solid–electrolyte interphase layers. The synergy between the cation and anion significantly improves cycling performance in asymmetric and symmetric control cells and a full cell paired with an LiFePO4 cathode. The present study provides a useful insight into the molecular engineering of electrolyte components by manipulating the charge and structures of the involved molecules. 相似文献
107.
Zheng Zhou Jiajun Wu Wenli Ma Feilin Dong Jiafeng Wang 《Journal of cellular and molecular medicine》2023,27(2):204
Necroptosis is a unique programmed death mechanism of necrotic cells. However, its role and specific mechanism in cancer remain unclear, and a systematic pan‐cancer analysis of necroptosis is yet to be conducted. Thus, we performed a specific pan‐cancer analysis using The Cancer Genome Atlas and Genotype‐Tissue Expression databases to analyse necroptosis expression in terms of cancer prognosis, DNA methylation status, tumour mutative burden, microsatellite instability, immune cell infiltration in different types of cancer and molecular mechanisms. For the first time, we explored the correlation between necroptosis and immunotherapy prognosis. Thus, our study provides a relatively comprehensive understanding of the carcinogenicity of necroptosis in different types of cancer. It is suggested that necroptosis can be used to evaluate the sensitivity of different patients to immunotherapy and may become a potential target for tumour immunotherapy. 相似文献
108.
Pan Y Chu T Dong S Hao Y Ren X Wang J Wang W Li C Zhang Z Zhou Y 《Molecular biology reports》2012,39(9):8581-8594
The study was designed to investigate feasibility of tissue culture in vitro utilizing static culture method. Annulus fibrosus cells obtained from spine of rabbits were cultured. Results showed that fibrous tissue infiltration could be detected in shallow layer. With extended time, tissue infiltration depth increased, but there were still a large amount of holes in central part. Fibrous tissue infiltration was detected in the control side products and inner infiltration wasn't obvious. Hydroxyproline content of the control side products gradually increased with extended culture time. Hydroxyproline content of the control side products in the third and fourth month was significantly higher than that in the first month, but lower than those of the experimental side products and normal annulus fibrosus cells. DNA content of the control side products in the third and fourth month was significantly increased compared to the first month. DNA content of the control side products at each phase point was significantly lower than that of the experimental side and normal annulus fibrosus cells. Furthermore, there was lower expression levels of the type I, II collagen mRNA and protein in the experimental side scaffolds compared to the control side product. This study demonstrates the successful formation of Intervertebral disc Anulus Fibrosus in vitro by static culture method. 相似文献
109.
110.