169 results on '"Yang, Xiaohe"'
Search Results
152. A RARE CASE OF MESENTERIC PLEXIFORM NEUROFIBROMA ASSOCIATED WITH GOBLET CELL CARCINOID AND GANGLIONEUROMA OF THE SMALL BOWEL.
- Author
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Li, Qing, Yang, Xiaohe, Ambros, Robert, and Qian, Jiang
- Published
- 2005
153. Metformin reduces basal subpopulation and attenuates mammary epithelial cell stemness in FVB/N mice.
- Author
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Shan M, Cheng Q, Parris AB, Kong L, Yang X, and Shi Y
- Abstract
Metformin shows promise in breast cancer prevention, but its underlying mechanisms remain unclear. This study investigated the impact of metformin on the repopulation dynamics of mammary epithelial cells (MECs) and the signaling pathways in non-tumorigenic FVB/N mice. This study aimed to enhance our understanding of the role of metformin in reducing the susceptibility of MECs in premalignant tissues to oncogenic factors. In this study, female mice were administered 200 mg/kg/day of metformin via intraperitoneal (i.p.) injection from 8 to 18 weeks of age. After this treatment period, morphogenesis, flow cytometry, analyses of MEC stemness, and RNA sequencing were performed. The study findings indicated that metformin treatment in adult mice reduced mammary gland proliferation, as demonstrated by decreased Ki67+ cells and lateral bud formation. Additionally, metformin significantly reduced both basal and mammary repopulating unit subpopulations, indicating an impact on mammary epithelial cell repopulation. Mammosphere, colony-forming cell, and 3D culture assays revealed that metformin adversely affected mammary epithelial cell stemness. Furthermore, metformin downregulated signaling in key pathways including AMPK/mTOR, MAPK/Erk, PI3K/Akt, and ER, which contribute to its inhibitory effects on mammary proliferation and stemness. Transcriptome analysis with RNA sequencing indicated that metformin induced significant downregulation of genes involved in multiple critical pathways. KEGG-based pathway analysis indicated that genes in PI3K/Akt, focal adhesion, ECM-receptor, small cell lung cancer and immune-modulation pathways were among the top groups of differentially regulated genes. In summary, our research demonstrates that metformin inhibits MEC proliferation and stemness, accompanied by the downregulation of intrinsic signaling. These insights suggest that the regulatory effects of metformin on premalignant mammary tissues could potentially delay or prevent the onset of breast cancer, offering a promising avenue for developing new preventive strategies., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Shan, Cheng, Parris, Kong, Yang and Shi.)
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- 2024
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154. Metabolic Profiles of Offspring Born From Biopsied Embryos from Toddlerhood to Preschool Age.
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Zhao J, Li S, Ban M, Gao S, Cui L, Yan J, Yang X, Li J, Zhang Y, Guan S, Zhou W, Gao X, and Chen ZJ
- Abstract
Context: Embryo biopsy, which is necessary for preimplantation genetic testing (PGT), has not been fully investigated regarding its potential influences and safety. Previous studies of children born from biopsied embryos (PGT children) have primarily centered around their growth and neuropsychological development, while there remains limited knowledge concerning their endocrine and metabolic parameters., Objective: This study aims to examine the effect of trophectoderm (TE) biopsy on metabolic outcomes for PGT children., Methods: A total of 1267 children from the Center for Reproductive Medicine, Shandong University, who were conceived through in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) with and without PGT, were analyzed in this study. Three sets of measurements pertaining to growth and metabolism were taken at each predetermined follow-up time point. The linear regression models within a generalized estimating equation were employed to examine the associations between the PGT and each outcome measure and the approach of false discovery rate was used to correct for multiple comparisons., Results: After controlling for confounding factors and correcting for multiple comparisons, no statistically significant difference was identified in any of the measured variables between the PGT children and children conceived by IVF alone (IVF children) and children conceived through IVF using ICSI (ICSI children). The same is true also for age- or sex-based subgroup analyses., Conclusion: Between the ages of 1 and 5 years, there are no clinically adverse metabolic outcomes observed in PGT children, and their metabolic profiles are essentially identical to those of IVF children and ICSI children., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)
- Published
- 2024
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155. First Report of Green Mould on Leaf of Phaseolus vulgaris Caused by Cladosporium tenuissimum in Liaoning, China.
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Gao X, Yang X, Li Y, Yu M, Ao J, Liu X, Sun Y, Song L, Chen F, and Guo L
- Abstract
Phaseolus vulgaris Linn. is a widely cultivated vegetable throughout the world. From spring 2019 to 2022, green mould symptoms were observed on leaves of P. vulgaris in the greenhouse in Liaoning, China, with disease incidence of 8-75% (plants) and 6-23% (leaves). Symptoms appeared as chlorotic lesions covered with dark green mould. The infections started at the apex or margin of the leaves and then spread inward with a characteristic "V" shape. Lesions exhibited curly morphology. 15 leaf samples with typical symptoms were collected from 5 different greenhouses. A total of 75 (5 replicates of each sample) leaf tissues (0.5 cm × 0.5 cm) were selected from the boundary between diseased and healthy parts. These samples were surface sterilized in 0.5% NaClO formin, rinsed 3 times in sterile distilled water and subsequently incubated at 28℃ on potato dextrose agar (PDA) supplemented with streptomycin (50 μg/ml). Numerous morphologically uniform colonies had been purified, with no other fungi observed. Afterwards, the strains were subcultured on malt extract agar (MEA). Colonies on MEA reached 70 to 80 mm diam after 14 days, smoke-grey to pale olivaceous-grey, woolly, sometimes radially wrinkled. The mycelia were pale olivaceous-grey, with hyphae measuring 1-5 μm wide (n = 20). The conidiophores were solitary or in groups of 2 to 5, and measured 50-280(-350) × 2.5-4 μm (n = 20), with 2-7 septa. The conidiogenous cells exhibited a cylindrical-oblong morphology and measured 10-44 × 5 μm (n = 20), with 0-2 septa, and the loci frequently thickened. The conidia were catenate in densely branched chains, ellipsoid to obovoid, smooth, and measured 2.5-5 × 2-3 μm (n = 50), with 0-4 septa. The morphological characteristics were similar to Cladosporium tenuissimum (Zhang 2003). The representative isolate KZ-19 was selected for molecular identification. The rDNA-ITS, translation elongation factor 1-α and actin genes were amplified, sequenced, and the resulting sequence data were submitted to GenBank (ITS: OQ931048; EF-1α: OQ954495; ACT: OQ954496). The BLAST results exhibited a 99 to 100% similarity with the sequences of C. tenuissimum type strain CBS 125995(ITS: HM148197; EF-1α: HM148442; ACT: HM148687). Furthermore, a multi-locus phylogenetic tree was constructed using the PhyloSuite (v 1. 2. 2) software, which revealed that the strains were most closely related to C. tenuissimum (Zhang et al. 2020). Based on both morphological and molecular characteristics, KZ-19 was finally identified as C. tenuissimum (Bensch 2012). Pathogenicity testing was performed on healthy 1-month-old P. vulgaris plants by inoculating the spore suspension (1×106 conidia/ml) of KZ-19 onto leaf surfaces, while control plants were simulated inoculated with sterile water, and five pots were used for each treatment. The test was performed under field conditions of 16-28°C (temperature) and 24-56% (relative humidity). Chlorotic lesions became evident within 2 days of inoculation, followed by the appearance of green mold on leaves after 7 days. No symptoms were observed in the control group. To fulfill Koch's postulates, the pathogen was re-isolated from three inoculated leaves. The morphological identification of re-isolated pathogens was similar to that of originally isolated pathogens. No infection was observed in non-inoculated control. To the best of our knowledge, this is the first report of C. tenuissimum causing green mould on P. vulgaris. As a ubiquitous saprobic hyphomycete, C. tenuissimum has been implicated in leaf mold in Punica granatum and Trifolium repens, larch bud blight, and strawberry blossom blight in previous years (He et al. 1987; Zhang et al. 2003; Zheng et al. 2010; Nam et al. 2015), presenting a potential threat to numerous crops. Therefore, an investigation of its distribution and pathogenic potential is essential in addition to the development of effective disease management strategies.
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- 2024
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156. First report of anthracnose caused by Colletotrichum kahawae on Hypericum chinensis in China.
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Ding J, Shen H, Yao L, Gao X, Zhang M, Wang Z, Li Y, and Yang X
- Abstract
Hypericum chinensis is growing in popularity amongst consumers in cut-flower and pop-flower market as an ornamental woody plant for its florid berry and colorful flower. In August 2019, a new leaf spot disease was observed on H. chinensis in three commercial nurseries in Kunming (25°05'N, 102°72'E), Yunnian province, China. Disease symptoms were observed on approximately 40% of the plants one year after planting and 30% of the leaves were infected. Leaf symptoms began as small, water-soaked lesions on young leaves which later became larger, dark brown and necrotic. The lesion size ranged from 0.2 to 2.8 cm in diameter. For pathogen isolation, three samples of symptomatic leaves were collected from four different nurseries. The leaves were cut into 0.5 mm pieces, surface sterilized using 70% ethanol for 30 s, and 3% NaOCl for 5 min, rinsed three times in sterilized distilled water and plated on potato dextrose agar (PDA) (Zhou et al. 2023). The plates were incubated at 26°C in the dark for 3 days. Eight isolates with comparable morphological characteristics were obtained. Initially, colonies produced pale gray to white aerial mycelia, turning dark gray after 5 days. The isolates produced hyaline, single celled, straight and cylindrical conidia, with mean size 9.7 to 14.8 μm long × 3.7 to 5.6 μm wide ( n = 100). Morphological characteristics were consistent with Colletotrichum sp. (Bailey and Jeger 1992). For molecular analysis, genomic DNA was extracted from three representative isolates (XSD1, XSD3 and XSD5), amplified using the primers ITS1/ITS4 (Yin et al. 2012) and T1/Bt2b (Glass and Donaldson 1995) and submitted to sequencing (Weir et al. 2012). DNA sequences of the isolates XSD2, XSD3 and XSD8 were identical. DNA sequences of a representative isolate XSD2 were deposited in GenBank (accession no. MW202334 for ITS, and OR347007 for TUB 2 ). MegaBLAST analysis of the ITS and TUB2 sequences showed 99.5% and 99.3% similarity with C. kahawae strain ICMP 18539 (accession no. NR_120138.1 for ITS) and strain IMI319418 (JX145227.1 for TUB 2 ). Pathogenicity tests were conducted by inoculating the pathogen on healthy mature leaves of H. chinensis in the field. Ten leaves (two leaves/plant) were inoculated by spraying conidial suspension (10
6 spores/ml) of isolates XSD1, XSD3 and XSD5, and covered with plastic bags to maintain high humidity for 48 hours, respectively. Leaves treated with sterile distilled water served as a control. All inoculated leaves showed symptoms similar to those observed in the field at 23±5°C 10 days after inoculation. No symptoms developed on non-inoculated leaves. The pathogen was re-isolated from inoculated diseased leaves and identified as C. kahawae based on morphological and molecular characters. C. kahawae has been reported to cause leaf spot on cultivated rocket in Italy (Garibaldi et al. 2016), and anthracnose disease on tree tomato in Colombia (Rojas et al. 2018), to our knowledge, this is the first report of C. kahawae causing anthracnose on H. chinensis worldwide. Due to important ornamental and economic value of H. chinensis , the distribution of C. kahawae needs to be investigated and monitored for effective disease management strategies to be developed.- Published
- 2023
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157. [Study on Clinical Application and Supervision of LC-MS in in Vitro Diagnosis Test].
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Ye C, Zhang L, Kou Y, Wang Y, and Yang X
- Subjects
- Chromatography, Liquid methods, Reference Standards, Japan, Tandem Mass Spectrometry methods
- Abstract
From the perspective of technical evaluation, this study reviewed the current situation of application and clinical application of medical device products were detected by liquid chromatography-tandem mass spectrometry in the market in recent years. The regulatory requirements of these products in China, USA, EU and Japan were compared and analyzed, and the monitoring situation of adverse events after listing, the standards for reference and the domestic and foreign regulatory documents were combined, the clinical application and regulatory risks of the product were analyzed. The problems such as pre-treatment, system matching, adequacy of performance index requirements, inter-room consistency, reference interval and registration unit were discussed and suggestions for supervision were given, with a view to the field of product R&D and production, review and approval of supervision to provide technical reference.
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- 2023
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158. [Analysis of Class II Common Problems in the Registration of in Vitro Diagnostic Reagent (Kit) for Clinical Chemistry].
- Author
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Yang X, Dong Q, Zhu W, and Zhen H
- Subjects
- China, Indicators and Reagents, Chemistry, Clinical standards, Reagent Kits, Diagnostic standards
- Abstract
From the perspective of technical review, this paper made statistics on the supplement contents of in vitro diagnostic reagent (kit) for clinical chemistry registered in Zhejiang province in the past five years, summarized and analyzed the common problems, and put forward corresponding suggestions based on the common problems encountered in the public welfare training of registered specialists in Zhejiang province. The aim is to provide technical reference for registrars to prepare registration documents reasonably and efficiently and for review staffs to strengthen their points of focus.
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- 2020
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159. [Study of the Application of Mobile Medical Technology in Construction of Grading Diagnosis and Treatment System].
- Author
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Zhu W, Shen Y, Zhen H, Yang X, and Hu K
- Subjects
- Public Health, Diagnosis, Mobile Applications, Technology trends
- Abstract
The combination of mobile medical technology and the grading diagnosis and treatment system (GDTS) can stimulate the allocation of medical resources, reduce medical cost and improve public health significantly. Firstly we summarize development features of mobile medical technology in foreign and domestic market, then we study the application model of mobile medical application in GDTS with field research data and analyzes its advantage and shortage. Finally, we propose four measures for further developing mobile medical application in the GDTS:the government departments should formulate policies and industry standards of products as soon as possible to meet requirement of market; service providers should take the hospitals as core role to achieve mutual benefit and win-win situation; take the daily monitoring of chronic diseases as an entry point to build profitable business model; enhance publicity to promote public health awareness.
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- 2018
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160. [Common Problems and Suggestions on Full Life-cycle Supervision and Administration of in Vitro Diagnostics].
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Yang X, Ma L, Wang W, and Zhen H
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- Diagnosis, Equipment and Supplies, Product Surveillance, Postmarketing
- Abstract
This article analyzes common problems and offers some suggestions on full life-cycle supervision and administration process of in vitro diagnostics, including premarket technical evaluations, pre-market QMS on-site inspections, postmarket adverse event surveillance, unannounced inspections and re-evaluation, from regulators' perspectives. It aims to provide technical reference for revisions on regulations, and help government administrators to figure out major points in daily regulatory practice.
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- 2018
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161. [Advice on Data Analysis Methods for Clinical Trials of Medical Devices].
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Yang X, He C, and Zhen H
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- Research Design, Statistics as Topic, Clinical Trials as Topic, Equipment and Supplies
- Abstract
This paper provides an overview on data analysis of medical devices undergoing clinical trials during medical device evaluation. It reports some common questions occurred in study design phase and data analysis phase. Then the paper proposes some advice on data analysis methods for different types of products, which may provide technical references for reviewers and clinical data analysts.
- Published
- 2017
162. Resveratrol induces apoptosis in breast cancer cells by E2F1-mediated up-regulation of ASPP1.
- Author
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Shi Y, Yang S, Troup S, Lu X, Callaghan S, Park DS, Xing Y, and Yang X
- Subjects
- Adaptor Proteins, Signal Transducing genetics, Apoptosis genetics, Apoptosis Regulatory Proteins genetics, Blotting, Western, Breast Neoplasms genetics, Cell Line, Tumor, E2F1 Transcription Factor genetics, Female, Gene Expression, Gene Expression Profiling, Gene Expression Regulation, Neoplastic, Humans, RNA, Small Interfering, Resveratrol, Reverse Transcriptase Polymerase Chain Reaction, Transfection, Up-Regulation, Adaptor Proteins, Signal Transducing biosynthesis, Antineoplastic Agents, Phytogenic pharmacology, Apoptosis drug effects, Apoptosis Regulatory Proteins biosynthesis, Breast Neoplasms metabolism, E2F1 Transcription Factor metabolism, Stilbenes pharmacology
- Abstract
Resveratrol is a natural polyphenolic compound with cancer chemopreventive activity. However, our understanding of the molecular mechanism responsible for resveratrol-induced apoptosis is still very limited. Here, we used MCF-7 and MDA-MB231 breast cancer cells as a model to demonstrate that resveratrol induced the expression of ASPP1, a new member of the ASPP (apoptosis stimulation protein of p53) family, which plays an important role in the regulation of apoptosis. Moreover, resveratrol enhanced apoptosis of MCF-7/ASPP1 cells, accompanied by higher expression of bax and p21. In contrast, siRNA-mediated knockdown of ASPP1 inhibited apoptosis in MB231 cells. Furthermore, we found that higher levels of ASPP1 were associated with adenovirus-mediated overexpression of E2F1 while siRNA-mediated E2F1 knockdown led to down-regulation of ASPP1. In conclusion, our results demonstrate that overexpression of ASPP1 rendered MCF-7 and MDA-MB231 breast cancer cells more sensitive to resveratrol-mediated apoptosis via the E2F pathway, thus suggesting that ASPP1 may represent a novel therapeutic target for resveratrol in human breast cancer.
- Published
- 2011
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163. Myrica rubra Extracts Protect the Liver from CCl(4)-Induced Damage.
- Author
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Xu L, Gao J, Wang Y, Yu W, Zhao X, Yang X, Zhong Z, and Qian ZM
- Abstract
The relationship between the expression of mitochondrial voltage-dependent anion channels (VDACs) and the protective effects of Myrica rubra Sieb. Et Zucc fruit extract (MCE) against carbon tetrachloride (CCl(4))-induced liver damage was investigated. Pretreatment with 50 mg kg(-1), 150 mg kg(-1) or 450 mg kg(-1) MCE significantly blocked the CCl(4)-induced increase in both serum aspartate aminotransferase (sAST) and serum alanine aminotransferase (sALT) levels in mice (P < .05 or .01 versus CCl(4) group). Ultrastructural observations of decreased nuclear condensation, ameliorated mitochondrial fragmentation of the cristae and less lipid deposition by an electron microscope confirmed the hepatoprotection. The mitochondrial membrane potential dropped from -191.94 ± 8.84 mV to -132.06 ± 12.26 mV (P < .01) after the mice had been treated with CCl(4). MCE attenuated CCl(4)-induced mitochondrial membrane potential dissipation in a dose-dependent manner. At a dose of 150 or 450 mg kg(-1) of MCE, the mitochondrial membrane potentials were restored (P < .05). Pretreatment with MCE also prevented the elevation of intra-mitochondrial free calcium as observed in the liver of the CCl(4)-insulted mice (P < .01 versus CCl(4) group). In addition, MCE treatment (50-450 mg kg(-1)) significantly increased both transcription and translation of VDAC inhibited by CCl(4). The above data suggest that MCE mitigates the damage to liver mitochondria induced by CCl(4), possibly through the regulation of mitochondrial VDAC, one of the most important proteins in the mitochondrial outer membrane.
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- 2011
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164. Cell density-dependent regulation of p73 in breast cancer cells.
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Tophkhane C, Yang S, Zhao ZJ, and Yang X
- Subjects
- Blotting, Western, Breast Neoplasms genetics, Cell Count, Cell Line, Tumor, DNA-Binding Proteins genetics, Female, Humans, Nuclear Proteins genetics, Protein Isoforms genetics, Protein Isoforms metabolism, Reverse Transcriptase Polymerase Chain Reaction, Tumor Protein p73, Tumor Suppressor Proteins genetics, Breast Neoplasms metabolism, Cell Communication physiology, DNA-Binding Proteins metabolism, Gene Expression Regulation, Neoplastic, Nuclear Proteins metabolism, Tumor Suppressor Proteins metabolism
- Abstract
Molecular regulation of p73, a p53 family member, remains unclear. Here we report that p73 expression is significantly regulated by cell densities. In particular, we found that p73alpha and p73beta are differentially regulated. While p73beta protein levels were inversely correlated with cell densities, p73alpha protein levels behaved oppositely. We further showed that density-dependent changes of p73alpha follow the same patterns as E2F-1 and TAp73 mRNA levels, suggesting transcriptional regulation. Our data also suggest that high levels of p73beta at lower densities may be due to increased protein stability. However, AIP-4/Itch appeared not to be involved in downregulation of p73beta at high densities. Moreover, we also found that subcellular location of p73 isoforms changes with the culture density increases. While high level of p73beta at low density was mainly presented in the nucleus, low levels of this protein at high densities were mainly in the cytosol. Taken together, these findings reveal a novel mechanism that differentially regulates p73 isoforms and underscores the role of cell-cell interaction in p73 regulation, which may advance our understanding of p73 expression and function in human cancers.
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- 2009
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165. Functional contrast and kinetic analysis of water-dispersible carbon black nanoparticles and MWNTs in glucose biosensors.
- Author
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Yang H, Yang X, Pan M, Chen Y, and Chen D
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- Biomedical Engineering, Enzymes, Immobilized, Glucose Oxidase, Kinetics, Microscopy, Electron, Transmission, Polystyrenes, Soot, Water, Biosensing Techniques methods, Glucose analysis, Nanoparticles ultrastructure, Nanotubes, Carbon ultrastructure
- Abstract
Poly (sodium 4-styrenesulfonate) (PSS) was grafted onto carbon black surface by ambient surface-initiated atom radical transfer polymerization. And the carbon paste electrodes modified by CB-g-PSS and MWNTs were completed. CB-g-PSS and MWNTs had no effect on direct electron transfer based on the carbon paste electrode, but increased the redox speed of Fe [(CN)(6)](3-) / Fe[(CN)(6)](4-) and led to stronger current response. The experimental results indicate that the sensitivity of modified by CB-g-PSS is 2.1 times of no modified, and MWNTs is 4 times. Measurable linear range is 1.1 mmol/L approximately 33.3 mmol/L. For sensors modified by CB-g-PSS, testing of different concentration glucose: RSD<7%; sensors modified by MWNTs, RSD<7.5% (glucose < 15 mmol/L), RSD<10% (glucose > 15 mmol/L) respectively.
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- 2009
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166. [Microstrip antenna design and system research of radio frequency identification temperature sensor].
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Yang H, Yang X, Chen Y, and Pan M
- Subjects
- Computer Communication Networks, Humans, Monitoring, Physiologic instrumentation, Radio Waves, Telemetry methods, Body Temperature, Radio Frequency Identification Device methods, Telemetry instrumentation, Transducers
- Abstract
Radio frequency identification sensor network, which is a product of integrating radio frequency identification (RFID) with wireless sensor network (WSN), is introduced in this paper. The principle of radio frequency identification sensor is analyzed, and the importance of the antenna is emphasized. Then three kinds of common antennae, namely coil antenna, dipole antenna and microstrip antenna, are discussed. Subsequently, according to requirement, we have designed a microstrip antenna in a wireless temperature-monitoring and controlling system. The measurement of factual effect showed the requirement was fulfilled.
- Published
- 2008
167. Disruption of Nrf2 enhances upregulation of nuclear factor-kappaB activity, proinflammatory cytokines, and intercellular adhesion molecule-1 in the brain after traumatic brain injury.
- Author
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Jin W, Wang H, Yan W, Xu L, Wang X, Zhao X, Yang X, Chen G, and Ji Y
- Subjects
- Animals, Cytokines analysis, Electrophoretic Mobility Shift Assay, Enzyme-Linked Immunosorbent Assay, Immunohistochemistry, Mice, Mice, Inbred ICR, Brain metabolism, Brain Injuries metabolism, Cytokines biosynthesis, Intercellular Adhesion Molecule-1 analysis, NF-E2-Related Factor 2 physiology, NF-kappa B metabolism
- Abstract
Inflammatory response plays an important role in the pathogenesis of secondary brain injury after traumatic brain injury (TBI). Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key transcription factor that plays a crucial role in cytoprotection against inflammation. The present study investigated the role of Nrf2 in the cerebral upregulation of NF-kappaB activity, proinflammatory cytokine, and ICAM-1 after TBI. Wild-type Nrf2 (+/+) and Nrf2 (-/-)-deficient mice were subjected to a moderately severe weight-drop impact head injury. Electrophoretic mobility shift assays (EMSAs) were performed to analyze the activation of nuclear factor kappa B (NF-kappaB). Enzyme-linked immunosorbent assays were performed to quantify the production of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6). Immunohistochemistry staining experiments were performed to detect the expression of intercellular adhesion molecule-1 (ICAM-1). Nrf2 (-/-) mice were shown to have more NF-kappaB activation, inflammatory cytokines TNF-alpha, IL-1beta and IL-6 production, and ICAM-1 expression in brain after TBI compared with their wild-type Nrf2 (+/+) counterparts. The results suggest that Nrf2 plays an important protective role in limiting the cerebral upregulation of NF-kappaB activity, proinflammatory cytokine, and ICAM-1 after TBI.
- Published
- 2008
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168. Mammary tumor heterogeneity in wt-ErbB-2 transgenic mice.
- Author
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Kosanke S, Edgerton SM, Moore D 2nd, Yang X, Mason T, Alvarez K, Jones L, Kim A, and Thor AD
- Subjects
- Adenocarcinoma genetics, Adenocarcinoma pathology, Animals, Diet, Female, Mammary Neoplasms, Animal pathology, Mice, Mice, Inbred Strains, Mice, Transgenic, Genes, erbB-2, Mammary Neoplasms, Animal genetics, Mammary Tumor Virus, Mouse genetics
- Abstract
Phenotypic and biological heterogeneity was studied in a single transgenic mouse model to determine the level of biological variance. We analyzed 1,258 tumors from 417 MMTV-wt-ErbB-2 transgenic mice, subdivided by casein or soy-based dietary randomization and hormonal treatment. Variance in tumor histologic features, growth pattern, invasion, metastases, and multi-focality were detected in untreated and treated mice. Ninety-three percent (1,174/1,258) of tumors had the solid growth pattern widely reported in this model. However, among the solid tumors, a spectrum of growth patterns, from well-circumscribed tumors with a pseudocapsule to locally invasive or highly aggressive, metastatic subtype, was observed. Of the non-solid tumors, glandular features were prominent in 84 (7%). Adenocarcinomas included papillary, acinar/glandular, and adenosquamous subtypes. Adenosquamous tumors were exclusively observed in the group of mice treated on a short-term basis with estrogen. In contrast to the reported literature for this transgenic mouse model, mammary tumors were multifocal in the majority of cases (303 of 417 mice, or 73%). Results of this extensive study of a single transgenic model of mammary tumorigenesis indicate phenotypic and biological heterogeneity not previously associated with this transgenic mouse. These data support a complex, multistep process of carcinogenesis and clonal evolution, with biological and phenotypic variance similar to that observed in human mammary cancer development.
- Published
- 2004
169. Hormonal and dietary modulation of mammary carcinogenesis in mouse mammary tumor virus-c-erbB-2 transgenic mice.
- Author
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Yang X, Edgerton SM, Kosanke SD, Mason TL, Alvarez KM, Liu N, Chatterton RT, Liu B, Wang Q, Kim A, Murthy S, and Thor AD
- Subjects
- Age Factors, Animals, Anticarcinogenic Agents adverse effects, Anticarcinogenic Agents pharmacology, Disease Models, Animal, Estradiol adverse effects, Estradiol blood, Estrogen Antagonists adverse effects, Estrogen Antagonists pharmacology, Estrogens, Non-Steroidal pharmacology, Female, Mammary Glands, Animal drug effects, Mammary Glands, Animal growth & development, Mammary Neoplasms, Experimental chemically induced, Mammary Neoplasms, Experimental genetics, Mammary Neoplasms, Experimental prevention & control, Mammary Tumor Virus, Mouse genetics, Mice, Mice, Transgenic, Phytoestrogens, Plant Preparations, Risk Factors, Tamoxifen adverse effects, Cocarcinogenesis, Diet, Estradiol pharmacology, Genes, erbB-2 genetics, Isoflavones, Mammary Neoplasms, Experimental etiology, Tamoxifen pharmacology
- Abstract
Exogenous and dietary estrogens have been associated with modification of breast cancer risk. Mammary cancer model systems can be used to explore interactions between specific transgenes, and hormonal and dietary factors. Transgenic mice bearing the rat wild-type erbB-2 gene were used to study the effects of short-term hormonal exposure [17beta-estradiol (E2) or tamoxifen] or a soy meal diet on mammary carcinogenesis. In mice fed a casein diet, mammary tumors developed at an earlier age after short-term E2 exposure during the early reproductive period. The median mammary tumor latency was shortest (29 weeks) for the high-dose estrogen as compared with the lowest dose of E2 treated or placebo control mice (33 and 37 weeks, respectively). The timing of short-term E2 exposure was also important, with the most significant changes observed in mice exposed to E2 between 8 and 18 weeks of age. E2 exposure was associated with the subsequent development of more aggressive tumors as determined by histologic grade, multifocal tumor development, stromal invasion, and pulmonary metastasis. In contrast, short-term tamoxifen-exposed mice generally failed to develop mammary tumors by 60 weeks of age. Mice fed a soy meal diet developed mammary tumors at a later age than casein-fed animals treated with E2 or placebo, whereas no differences were observed by diet for the tamoxifen-treated mice. Mammary tumor prevention was >80% in tamoxifen-treated mice on either diet. Novel histologic tumor types were identified, suggesting greater phenotypic diversity than described previously. Benign mammary gland morphogenesis was also significantly altered by short-term hormonal exposure or dietary factors, consistent with the modification of mammary tumor risk in specific treatment groups. Estrogenic modulation of the mammary tumor phenotype in wild-type erbB-2 transgenic mice was observed. Histologic tumor types and clinical aggressivity not reported previously in this transgenic model were noted, suggesting greater biologic heterogeneity than reported previously. In addition, dietary phytoestrogens modified mammary development and tumor latency, suggesting a need for greater stringency in dietary assignment for transgenic mouse models of mammary neoplasia.
- Published
- 2003
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