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Find video protocols related to scientific articles indexed in Pubmed.
Radix Angelicae Sinensis and Radix Hedysari enhance radiosensitivity of 12C6+ radiation in human liver cancer cells by modulating apoptosis protein.
Saudi Med J
PUBLISHED: 09-18-2014
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To investigate the radiosensitizing effects of Radix Angelicae Sinensis-Radix Hedysari (RAS-RH [an ultra-filtration extract]) and its underlying mechanisms in human liver cancer cells H22.
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Zearalenone exposure affects epigenetic modifications of mouse eggs.
Mutagenesis
PUBLISHED: 08-25-2014
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Zearalenone (ZEA) is a mycotoxin produced by various Fusarium fungi, which has been shown to cause several cases of mycotoxicosis in farm animals and humans. However, there is no evidence regarding the effect of ZEA on mouse egg developmental competence. In this study, we found that the activation rate of maturated oocytes was affected in mice by ZEA treatment, indicating that ZEA affects egg developmental competence. And we explored possible mechanisms of low mouse maturated oocyte developmental competence after ZEA treatment from an epigenetic modification perspective. The fluorescence intensity analysis showed that 5-methyl cytosine level increased after ZEA treatment, indicating that the general DNA methylation level increased in the treated eggs. Moreover, histone methylations were also altered: H3K4me2 as well as H3K9me3 and H4K20me1, me2, me3 levels decreased in eggs that were cultured in high-dose ZEA medium. Thus, our results indicated that ZEA decreased egg developmental competence by affecting the epigenetic modifications.
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Structural elucidation of sorghum lignins from an integrated biorefinery process based on hydrothermal and alkaline treatments.
J. Agric. Food Chem.
PUBLISHED: 08-04-2014
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An integrated process based on hydrothermal pretreatment (HTP) (i.e., 110-230 °C, 0.5-2.0 h) and alkaline post-treatment (2% NaOH at 90 °C for 2.0 h) has been performed for the production of xylooligosaccharide, lignin, and digestible substrate from sweet sorghum stems. The yield, purity, dissociation mechanisms, structural features, and structural transformations of alkali lignins obtained from the integrated process were investigated. It was found that the HTP process facilitated the subsequent alkaline delignification, releasing lignin with the highest yield (79.3%) and purity from the HTP residue obtained at 190 °C for 0.5 h. All of the results indicated that the cleavage of the ?-O-4 linkages and degradation of ?-? and ?-5 linkages occurred under the harsh HTP conditions. Depolymerization and condensation reactions simultaneously occurred at higher temperatures (? 170 °C). Moreover, the thermostability of lignin was positively related to its molecular weight, but was also affected by the inherent structures, such as ?-O-4 linkages and condensed units. These findings will enhance the understanding of structural transformations of the lignins during the integrated process and maximize the potential utilizations of the lignins in a current biorefinery process.
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CYLD mediates ciliogenesis in multiple organs by deubiquitinating Cep70 and inactivating HDAC6.
Cell Res.
PUBLISHED: 08-01-2014
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Cilia are hair-like organelles extending from the cell surface with important sensory and motility functions. Ciliary defects can result in a wide range of human diseases known as ciliopathies. However, the molecular mechanisms controlling ciliogenesis remain poorly defined. Here we show that cylindromatosis (CYLD), a tumor suppressor protein harboring deubiquitinase activity, plays a critical role in the assembly of both primary and motile cilia in multiple organs. CYLD knockout mice exhibit polydactyly and various ciliary defects, such as failure in basal body anchorage and disorganization of basal bodies and axenomes. The ciliary function of CYLD is partially attributed to its deconjugation of the polyubiquitin chain from centrosomal protein of 70 kDa (Cep70), a requirement for Cep70 to interact with ?-tubulin and localize at the centrosome. In addition, CYLD-mediated inhibition of histone deacetylase 6 (HDAC6), which promotes tubulin acetylation, constitutes another mechanism for the ciliary function of CYLD. Small-molecule inhibitors of HDAC6 could partially rescue the ciliary defects in CYLD knockout mice. These findings highlight the importance of protein ubiquitination in the modulation of ciliogenesis, identify CYLD as a crucial regulator of this process, and suggest the involvement of CYLD deficiency in ciliopathies.
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EZH2 is essential for development of mouse preimplantation embryos.
Reprod. Fertil. Dev.
PUBLISHED: 07-30-2014
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Enhancer of zeste homologue 2 (Ezh2) is essential for the development of the early mouse preimplantation embryo. Loss of Ezh2 results in embryonic lethality in mice. Ezh2-deficient embryos display impaired outgrowth potential, defective establishment of Ezh2-null embryonic stem (ES) cells and adherence and differentiation of the trophoblast layer into giant cells. We investigated if Ezh2 controls the fate of embryos at an earlier stage by treating with cycloheximide (CHX) or microinjecting short interfering RNA (siRNA) to restrict embryonic Ezh2 expression during preimplantation. CHX inhibited de novo EZH2 protein synthesis in zygotes, suggesting that EZH2 requires de novo synthesis during post-fertilisation stages. We found that loss of Ezh2 at the pronuclear stage caused severe growth retardation and reduced blastocyst formation. Expression of the pluripotency-associated markers Oct4, Sox2 and Nanog were significantly decreased in embryos that had been injected with Ezh2 siRNA. In addition, Ezh2 loss induced upregulated expression of genes related to the differentiation of germ layers, including Gata6, Hoxb1 and Hand1. Finally, apoptosis was increased in the blastocyst embryos with Ezh2 knockdown. Modification of histone H3-Lysine 27 de-methylation and tri-methylation (H3K27me2/3) was strongly reduced in Ezh2 siRNA embryos. We conclude that Ezh2 is essential for early preimplantation embryo development through the regulation of epigenetic modification and apoptosis.
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[Investigation of exogenous stimulus effect on the interaction of CdSe/ZnS quantum dots/TiO2 nanocomposites with human serum albumin by resonance light scattering].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 07-11-2014
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The interaction between CdSe/ZnS(quantum dots)/TiO2 nanocomposites and human serum albumin(HSA) was investigated by resonance light scattering (RLS) spectroscopic methods under approximate physiological conditions. Much important information of the interaction between CdSe/ZnS(Quantum Dots)/TiO2 nanocomposites and HSA was obtained by studying comprehensively the Exogenous influence factors of nanocomposites concentration, pH, NaCl concentration, reaction temperature, detection time, coexisting ions, surfactants, sequence of adding to the sample etc. It was showed that the new formation of complex system is likely to enhance the protein hydrophobic cavity and tend to focus the hydrophobic interface in aqueous solution, resulting in strengthening the intensity of resonance light scattering; Also it is very sensitive to the changes in the pH value in the system; The sensitivity of I(RLS) in system can be increased by the appropriate NaCl concentration; The value of IRLS in system would be changed with the change in the concentration of coexisting ions; The value of I(RLS) in system is basically stable when the reaction time reaches 5 min; The value of I(RLS) in system is not exactly the same with a surfactant, and strong electrostatic interaction has occurred between oppositely charged surfactant and nano composites; It is obvious that the value of I(RLS) in complex system is affected by the sequence of adding to sample; It has the incomplete monotonically increasing trend with the changes in temperature. The information is useful for providing theoretical supporting for the mechanism of interaction between nanomaterials and bio-macromolecule, and for understanding the biocompatibility and safety of nano-materials.
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TPL2 mediates autoimmune inflammation through activation of the TAK1 axis of IL-17 signaling.
J. Exp. Med.
PUBLISHED: 06-30-2014
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Development of autoimmune diseases, such as multiple sclerosis and experimental autoimmune encephalomyelitis (EAE), involves the inflammatory action of Th1 and Th17 cells, but the underlying signaling mechanism is incompletely understood. We show that the kinase TPL2 is a crucial mediator of EAE and is required for the pathological action of Th17 cells. TPL2 serves as a master kinase mediating the activation of multiple downstream pathways stimulated by the Th17 signature cytokine IL-17. TPL2 acts by linking the IL-17 receptor signal to the activation of TAK1, which involves a dynamic mechanism of TPL2-TAK1 interaction and TPL2-mediated phosphorylation and catalytic activation of TAK1. These results suggest that TPL2 mediates TAK1 axis of IL-17 signaling, thereby promoting autoimmune neuroinflammation.
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Structural features and antioxidant activities of lignins from steam-exploded bamboo (Phyllostachys pubescens).
J. Agric. Food Chem.
PUBLISHED: 06-13-2014
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An environmentally friendly steam explosion process of bamboo, followed by alkali and alkaline ethanol delignification, was developed to fractionate lignins. Results showed that after steam explosion the lignins isolated showed relatively low carbohydrate contents (0.55-1.76%) and molecular weights (780-1050 g/mol). For each steam-exploded sample, alkali-extracted lignins presented higher phenolic OH values (1.41-1.82 mmol/g), p-coumaric acid to ferulic acid ratios (pCA/FA ratios 4.5-14.1), and syringyl to guaiacyl ratios (S/G ratios 5.0-8.5) than those from alkaline ethanol-extracted lignins (phenolic OH 0.85-1.35 mmol/g, pCA/FA ratios 1.6-5.2, and S/G ratios 3.5-4.8). The lignins obtained consisted mainly of ?-O-4' linkages combined with small amounts of ?-?', ?-5', and ?-O-4/?-O-4 linkages. Antioxidant activities of the lignins obtained were tested by the 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azobis(3-ethylbenzothiazoline-6-sulfonic acid), and ferric reducing activity power methods. It was found that alkali-extracted lignins obtained during the initial extraction process had higher antioxidant activities than alkaline ethanol-extracted lignins obtained during the second extraction process.
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T cell-intrinsic function of the noncanonical NF-?B pathway in the regulation of GM-CSF expression and experimental autoimmune encephalomyelitis pathogenesis.
J. Immunol.
PUBLISHED: 06-04-2014
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The noncanonical NF-?B pathway induces processing of the NF-?B2 precursor protein p100, and thereby mediates activation of p52-containing NF-?B complexes. This pathway is crucial for B cell maturation and humoral immunity, but its role in regulating T cell function is less clear. Using mutant mice that express a nonprocessible p100, NF-?B2(lym1), we show that the noncanonical NF-?B pathway has a T cell-intrinsic role in regulating the pathogenesis of a T cell-mediated autoimmunity, experimental autoimmune encephalomyelitis (EAE). Although the lym1 mutation does not interfere with naive T cell activation, it renders the Th17 cells defective in the production of inflammatory effector molecules, particularly the cytokine GM-CSF. We provide evidence that p52 binds to the promoter of the GM-CSF-encoding gene (Csf2) and cooperates with c-Rel in the transactivation of this target gene. Introduction of exogenous p52 or GM-CSF to the NF-?B2(lym1) mutant T cells partially restores their ability to induce EAE. These results suggest that the noncanonical NF-?B pathway mediates induction of EAE by regulating the effector function of inflammatory T cells.
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Rab5a is required for spindle length control and kinetochore-microtubule attachment during meiosis in oocytes.
FASEB J.
PUBLISHED: 05-31-2014
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Rab GTPases are highly conserved components of vesicle trafficking pathways. Rab5, as a master regulator of endocytic trafficking, has been shown to function in membrane tethering and docking. However, the function of Rab5 in meiosis has not been addressed. Here, we report elongated spindles and misaligned chromosomes, with kinetochore-microtubule misattachments, on specific depletion of Rab5a in mouse oocytes. Moreover, the localization and levels of centromere protein F (CENPF), a component of the nuclear matrix, are severely reduced at kinetochores in metaphase oocytes following Rab5a knockdown. Consistent with this finding, nuclear lamina disassembly in the transition from prophase arrest to meiosis I is also impaired in Rab5a-depleted oocytes. Notably, oocyte-specific ablation of CENPF phenocopies the meiotic defects resulting from Rab5a knockdown. In summary, our data support a model where Rab5a-positive vesicles, likely through interaction with nuclear lamina, modulate CENPF localization and levels at centromeres, consequently ensuring proper spindle length and kinetochore-microtubule attachment in meiotic oocytes.-Ma, R., Hou, X., Zhang, L., Sun, S.-C., Schedl, T., Moley, K., Wang, Q. Rab5a is required for spindle length control and kinetochore-microtubule attachment during meiosis in oocytes.
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[Treatment of flexion-distraction thoracolumbar fractures by postural reduction with instrumental reduction].
Zhongguo Gu Shang
PUBLISHED: 05-16-2014
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To study the curative effect of postural reduction with instrumental reduction in treatment of flexion-distraction thoracolumbar fractures.
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Effect of mycotoxin-containing diets on epigenetic modifications of mouse oocytes by fluorescence microscopy analysis.
Microsc. Microanal.
PUBLISHED: 05-09-2014
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Mycotoxins, such as aflatoxin (AF), fumonisin B1, zearalenone (ZEA), and deoxynivalenol (DON), are commonly found in many food commodities. Mycotoxins have been shown to increase DNA methylation levels in a human intestinal cell line. We previously showed that the developmental competence of oocytes was affected in mice that had been fed a mycotoxin-containing diet. In this study, we explored possible mechanisms of low mouse oocyte developmental competence after mycotoxin treatment in an epigenetic modification perspective. Mycotoxin-contaminated maize (DON at 3,875 ?g/kg, ZEA at 1,897 ?g/kg, and AF at 806 ?g/kg) was included in diets at three different doses (mass percentage: 0, 15, and 30%) and fed to mice for 4 weeks. The fluorescence intensity analysis showed that the general DNA methylation levels increased in oocytes from high dose mycotoxin-fed mice. Mouse oocyte histone methylation was also altered. H3K9me3 and H4K20me3 level increased in oocytes from mycotoxin-fed mice, whereas H3K27me3 and H4K20me2 level decreased in oocytes from mycotoxin-fed mice. Thus, our results indicate that naturally occurring mycotoxins have effects on epigenetic modifications in mouse oocytes, which may be one of the reasons for reduced oocyte developmental competence.
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WASH complex regulates Arp2/3 complex for actin-based polar body extrusion in mouse oocytes.
Sci Rep
PUBLISHED: 05-06-2014
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Prior to their fertilization, oocytes undergo asymmetric division, which is regulated by actin filaments. Recently, WASH complex were identified as actin nucleation promoting factors (NPF) that activated Arp2/3 complex. However, the roles of WASH complex remain uncertain, particularly for oocyte polarization and asymmetric division. Here, we examined the functions of two important subunits of a WASH complex, WASH1 and Strumpellin, during mouse oocyte meiosis. Depleting WASH1 or disrupting Strumpellin activity by WASH1 morpholino (MO) injection or Strumpellin antibody injection decreased polar body extrusion and caused oocyte symmetric division, and this may have been due to spindle formation and migration defects. Time lapse microscopy showed that actin filaments distribution and relative amount at the membrane and in the cytoplasm of oocytes was significantly decreased after disrupting WASH complex. In addition, Arp2/3 complex expression was reduced after WASH1 depletion. Thus, our data indicated that WASH complex regulated Arp2/3 complex and were required for cytokinesis and following polar body extrusion during mouse oocyte meiotic maturation.
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Adipose-derived stem cells transfected with pEGFP-OSX enhance bone formation during distraction osteogenesis.
J Zhejiang Univ Sci B
PUBLISHED: 05-06-2014
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This study was designed to investigate the effects of local delivery of adipose-derived stem cells (ADSCs) transfected with transcription factor osterix (OSX) on bone formation during distraction osteogenesis. New Zealand white rabbits (n=54) were randomly divided into three groups (18 rabbits per group). A directed cloning technique was used for the construction of recombinant plasmid pEGFP-OSX, where EGFP is the enhanced green fluorescence protein. After osteodistraction of the right mandible of all experimental rabbits, rabbits in group A were treated with ADSCs transfected with pEGFP-OSX, group B with ADSCs transfected with pEGFP-N1, and group C with physiological saline. Radiographic and histological examinations were processed after half of the animals within each group were humanely killed by injection of sodium pentothal at Week 2 or 6 after surgery. The distraction bone density was measured as its projectional bone mineral density (BMD). Three parameters were measured, namely, the thickness of new trabeculae (TNT), and the volumes of the newly generated cortical bone (NBV1) and the cancellous bone (NBV2) of the distracted regions. Good bone generation in the distraction areas was found in group A, which had the highest BMD, TNT, and NBV in the distraction zones among the groups. There was no significant difference in bone generation in the distraction areas between groups B and C. The results indicate that the transplantation of ADSCs transfected with pEGFP-OSX can effectively promote bone generation during distraction in vivo.
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Structural characterization of residual hemicelluloses from hydrothermal pretreated Eucalyptus fiber.
Int. J. Biol. Macromol.
PUBLISHED: 04-19-2014
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In this study, an environmental-friendly hydrothermal pretreatment of Eucalyptus fiber followed with alkali post-treatment was developed to produce bioethanol efficiently. This biorefinery process allowed all major components of biomass being converted into high value-added products. The chemical and structural features of the residual hemicelluloses isolated with alkali from the hydrothermal pretreated Eucalyptus fiber, were comparatively investigated. Sugar and spectral analyses indicated that the hemicelluloses were mainly composed of glucuronoxylans, and especially hemicelluloses prepared at higher temperature (180°C) contained higher contents of glucomannans and ?-glucan. Hydrothermal pretreatment resulted in a significant hydrolysis of the glycosidic linkages in xylan backbone, and thus the molecular weight of the hemicelluloses was significantly reduced from 56,520 to 7780g/mol with the increase of temperature. This suggested that a combination of hydrothermal pretreatment at low temperatures (100-140°C) and alkali post-treatment was an effective technique for isolating of hemicelluloses from Eucalyptus fiber.
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Involvement of Dynamin 2 in actin-based polar-body extrusion during porcine oocyte maturation.
Mol. Reprod. Dev.
PUBLISHED: 04-15-2014
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Mammalian oocyte meiotic maturation involves a unique asymmetric division, but the regulatory mechanisms and signaling pathways involved are poorly understood. Dynamins are ubiquitous eukaryotic GTPases involved in membrane trafficking and actin dynamics, whose roles in mammalian oocyte maturation have not been determined. In this study, we used porcine oocytes to show that Dynamin 2 accumulated at the meiotic spindle and in the cortex of oocytes, with a distribution similar to that of actin. Inhibiting Dynamin 2 activity in porcine oocytes with the specific inhibitor dynasore resulted in failed polar-body extrusion. This phenotype may have been due to aberrant actin distribution and/or spindle positioning as inhibitor treatment disrupted the formation of the actin cap and cortical granule-free domain, which negatively impacted spindle positioning. Moreover, the distribution of ARP2, a key actin-nucleation factor, was severely reduced in the cortex after dynasore treatment. Thus, our results suggest that Dynamin 2 possibly regulates porcine oocyte maturation through its effects on actin-mediated spindle positioning and cytokinesis, and that this may depend on regulating ARP2 localization.
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Characteristics and enzymatic hydrolysis of cellulose-rich fractions from steam exploded and sequentially alkali delignified bamboo (Phyllostachys pubescens).
Bioresour. Technol.
PUBLISHED: 04-06-2014
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In this study, cellulose-rich fractions from bamboo were prepared with steam explosion pretreatment (SEP) followed by a successive alkaline delignification to improve the enzymatic digestibility for an efficient bioethanol production. The cellulose-rich fractions obtained were characterized by FT-IR, XRD, CP/MAS (13)C NMR, SEM, and BET surface area. It was found that the SEP alone significantly removed partial hemicelluloses, while the synergistic treatment by SEP and alkaline delignification removed most hemicelluloses and lignin. Results from enzymatic hydrolysis showed that SEP alone improved the enzymatic hydrolysis rate by 7.9-33.1%, while the synergistic treatment by SEP and alkaline delignification enhanced the rate by 45.7-63.9%. The synergistic treatment by SEP at 2.0 MPa for 5 min with water impregnation followed by a successive alkaline delignification with 0.5% NaOH and 70% ethanol containing 1.5% NaOH resulted in a maximum enzymatic hydrolysis rate of 70.6%.
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Isolated pancreatic tuberculosis in non-immunocompromised patient treated by Whipple's procedure: a case report.
Chin. Med. Sci. J.
PUBLISHED: 04-05-2014
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PANCREATIC tuberculosis (TB) is a rare disease and its diagnosis is difficult because of the lack of specific clinical manifestations. Computed tomography (CT) and magnetic resonance imaging (MRI) have some diagnostic values in this disease, but it is easy to misdiagnose pancreatic TB as a pancreatic tumor.1 In this article, we present a case of non-immunocompromised patient developing an isolated pancreatic TB, report the CT and MRI findings, and the surgical procedure for it.
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Zearalenone exposure affects mouse oocyte meiotic maturation and granulosa cell proliferation.
Environ. Toxicol.
PUBLISHED: 03-28-2014
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Zearalenone (ZEN) is a metabolite of Fusarium and is a common contaminant of grains and foodstuffs. ZEN acts as a xenoestrogen and is considered to be cytotoxic, tissue toxic, and genotoxic, which causes abortions and stillbirths in humans and animals. Since estrogens affect oocyte maturation during meiosis, in this study we investigated the effects of ZEN on mouse oocyte meiotic maturation and granulosa cell proliferation. Our results showed that ZEN-treated oocyte maturation rates were decreased, which might be due to the disrupted cytoskeletons: (1) ZEN treatment resulted in significantly more oocytes with abnormal spindle morphologies; (2) actin filament expression and distribution were also disrupted after ZEN treatment, which was confirmed by the aberrant distribution of actin regulatory proteins. In addition, cortical granule-free domains (CGFDs) were disrupted after ZEN treatment, which indicated that ZEN may affect mouse oocyte fertilization capability. ZEN reduced mouse granulosa cell proliferation in a dose-dependent manner as determined by MTT assay and TUNEL apoptosis analysis, which may be another cause for the decreased oocyte maturation. Thus, our results demonstrated that exposure to zearalenone affected oocyte meiotic maturation and granulosa cell proliferation in mouse. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014.
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Inflammatory T cell responses rely on amino acid transporter ASCT2 facilitation of glutamine uptake and mTORC1 kinase activation.
Immunity
PUBLISHED: 03-24-2014
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Glutamine has been implicated as an immunomodulatory nutrient, but how glutamine uptake is mediated during T cell activation is poorly understood. We have shown that naive T cell activation is coupled with rapid glutamine uptake, which depended on the amino acid transporter ASCT2. ASCT2 deficiency impaired the induction of T helper 1 (Th1) and Th17 cells and attenuated inflammatory T cell responses in mouse models of immunity and autoimmunity. Mechanistically, ASCT2 was required for T cell receptor (TCR)-stimulated activation of the metabolic kinase mTORC1. We have further shown that TCR-stimulated glutamine uptake and mTORC1 activation also required a TCR signaling complex composed of the scaffold protein CARMA1, the adaptor molecule BCL10, and the paracaspase MALT1. This function was independent of IKK kinase, a major downstream target of the CARMA1 complex. These findings highlight a mechanism of T cell activation involving ASCT2-dependent integration of the TCR signal and a metabolic signaling pathway.
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Ezetimibe-Mediated Protection of Vascular Smooth Muscle Cells from Cholesterol Accumulation through the Regulation of Lipid Metabolism-Related Gene Expression.
Pharmacology
PUBLISHED: 03-03-2014
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Background: Ezetimibe is a potent inhibitor of Niemann-Pick type C1-Like 1 and has been approved for the treatment of hypercholesterolemia. Our preliminary study showed that ezetimibe promotes cholesterol ef?ux from vascular smooth muscle cells (VSMCs). Our aim was to investigate the cellular mechanisms underlying the ezetimibe actions. Methods and Results: Rat VSMCs were converted to foam cells by incubation with cholesterol:methyl-?-cyclodextrin. The intracellular free cholesterol, total cholesterol, and the ratio of cholesteryl ester to total cholesterol were decreased after the incubation of VSMCs with different concentrations of ezetimibe (3, 10, 30, and 30 ?mol/l) or treated with 30 ?mol/l of ezetimibe for different time periods (6, 12, 24, and 48 h). Our results also showed that the expression of caveolin-1, liver X receptor ?, and ATP-binding cassette transporter ABCA1 was enhanced, but the expression of nSREBP-1c was decreased in a concentration- and time-dependent manner. RNA interference was used to determine the roles of caveolin-1 and SREBP-1 in the lipid-lowering effect of ezetimibe. The results showed that caveolin-1 was involved in the regulation of intracellular cholesterol content, and the expression of caveolin-1 was repressed by SREBP-1. Conclusion: The present study indicates that ezetimibe protects VSMCs from cholesterol accumulation by regulating the expression of lipid metabolism-related genes. © 2014 S. Karger AG, Basel.
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USP15 stabilizes MDM2 to mediate cancer-cell survival and inhibit antitumor T cell responses.
Nat. Immunol.
PUBLISHED: 02-19-2014
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Deubiquitinases (DUBs) are a new class of drug targets, although the physiological function of only few DUBs has been characterized. Here we identified the DUB USP15 as a crucial negative regulator of T cell activation. USP15 stabilized the E3 ubiquitin ligase MDM2, which in turn negatively regulated T cell activation by targeting the degradation of the transcription factor NFATc2. USP15 deficiency promoted T cell activation in vitro and enhanced T cell responses to bacterial infection and tumor challenge in vivo. USP15 also stabilized MDM2 in cancer cells and regulated p53 function and cancer-cell survival. Our results suggest that inhibition of USP15 may both induce tumor cell apoptosis and boost antitumor T cell responses.
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Chk2 regulates cell cycle progression during mouse oocyte maturation and early embryo development.
Mol. Cells
PUBLISHED: 02-19-2014
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As a tumor suppressor homologue during mitosis, Chk2 is involved in replication checkpoints, DNA repair, and cell cycle arrest, although its functions during mouse oocyte meiosis and early embryo development remain uncertain. We investigated the functions of Chk2 during mouse oocyte maturation and early embryo development. Chk2 exhibited a dynamic localization pattern; Chk2 expression was restricted to germinal vesicles at the germinal vesicle (GV) stage, was associated with centromeres at pro-metaphase I (Pro-MI), and localized to spindle poles at metaphase I (MI). Disrupting Chk2 activity resulted in cell cycle progression defects. First, inhibitor-treated oocytes were arrested at the GV stage and failed to undergo germinal vesicle breakdown (GVBD); this could be rescued after Chk2 inhibition release. Second, Chk2 inhibition after oocyte GVBD caused MI arrest. Third, the first cleavage of early embryo development was disrupted by Chk2 inhibition. Additionally, in inhibitor-treated oocytes, checkpoint protein Bub3 expression was consistently localized at centromeres at the MI stage, which indicated that the spindle assembly checkpoint (SAC) was activated. Moreover, disrupting Chk2 activity in oocytes caused severe chromosome misalignments and spindle disruption. In inhibitor-treated oocytes, centrosome protein ?-tubulin and Polo-like kinase 1 (Plk1) were dissociated from spindle poles. These results indicated that Chk2 regulated cell cycle progression and spindle assembly during mouse oocyte maturation and early embryo development.
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ROCK inhibition prevents early mouse embryo development.
Histochem. Cell Biol.
PUBLISHED: 02-16-2014
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ROCK is a Rho-GTPase effector that is important for actin assembly and is involved in various cellular functions, including cell contraction, migration, motility, and tumor cell invasion. In this study, we investigated ROCK expression and function during early mouse embryo development. Inhibiting ROCK by Y-27632 treatment at the zygote stage resulted in first cleavage failure, and most embryos failed to develop to the 8-cell stage. When adding Y-27632 at the 8-cell stage, embryos failed to undergo compaction and could not develop into blastocysts. In addition, fluorescence staining intensity analysis indicated that actin expression at blastomere membranes was significantly reduced. After ROCK inhibition, two or more nuclei were observed in a cell, which indicated possible cytokinesis failure. Moreover, after ROCK inhibition with Y-27632, the phosphorylation levels of LIMK1/2, a downstream molecule of ROCK, were decreased at blastomere membranes. Thus, our results showed conserved roles for ROCK in this mammalian embryo model and indicated that a ROCK-LIMK1/2-actin pathway might regulate cleavage and blastocyst formation during early mouse embryo development.
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Dynamin 2 regulates actin-mediated spindle migration in mouse oocytes.
Biol. Cell
PUBLISHED: 02-04-2014
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During meiosis, a bipolar spindle forms in the central cytoplasm of an oocyte and then moves to the cortex to extrude the first polar body. This is dependent on the regulation of actin and actin-related molecules. Dynamin 2, a large guanosine triphosphatases (GTPase) known to regulate clathrin-mediated endocytosis, is involved in actin recruitment and actin-based vesicle mobility. In this study, we investigated the role of Dynamin 2 in oocyte meiosis.
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Integrated biorefinery based on hydrothermal and alkaline treatments: investigation of sorghum hemicelluloses.
Carbohydr Polym
PUBLISHED: 01-27-2014
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An integrated process based on hydrothermal pretreatment (HTP) and alkaline post-treatment was proposed to treat sweet sorghum stem. The structural features of the alkali-soluble hemicelluloses (ASHs) obtained from the un-pretreated and hydrothermally pretreated materials were comprehensively investigated by HPAEC, GPC, NMR, FT-IR, and TGA techniques. The ASH with the highest yield (60.6%) was obtained from the HTP residue performed at 130 °C for 1.0 h. All the results indicated that the ASHs had a more linear structure with increasing the pretreatment temperature (110-170 °C). The molecular weights of the ASHs were decreased with increasing the pretreatment temperature, suggesting that C-O bonds in the ASHs were gradually cleaved, especially at the higher temperatures (? 170 °C). Interestingly, the integrated process yielded more homogeneous ASHs than hemicelluloses obtained from the un-pretreated material. Based on the spectral analyses, the structure of the ASHs was assumed to be L-arabino-4-O-methyl-D-glucurono-D-xylan.
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CYLD regulates spindle orientation by stabilizing astral microtubules and promoting dishevelled-NuMA-dynein/dynactin complex formation.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 01-27-2014
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Oriented cell division is critical for cell fate specification, tissue organization, and tissue homeostasis, and relies on proper orientation of the mitotic spindle. The molecular mechanisms underlying the regulation of spindle orientation remain largely unknown. Herein, we identify a critical role for cylindromatosis (CYLD), a deubiquitinase and regulator of microtubule dynamics, in the control of spindle orientation. CYLD is highly expressed in mitosis and promotes spindle orientation by stabilizing astral microtubules and deubiquitinating the cortical polarity protein dishevelled. The deubiquitination of dishevelled enhances its interaction with nuclear mitotic apparatus, stimulating the cortical localization of nuclear mitotic apparatus and the dynein/dynactin motor complex, a requirement for generating pulling forces on astral microtubules. These findings uncover CYLD as an important player in the orientation of the mitotic spindle and cell division and have important implications in health and disease.
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The complete mitochondrial genome of Scapharca kagoshimensis (Bivalvia: Arcidae).
Mitochondrial DNA
PUBLISHED: 01-14-2014
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Abstract In this paper, the complete mitochondrial genome of Scapharca kagoshimensis (Bivalvia: Arcidae) was determined. It is 46,713 in length, which contains 12 protein-coding genes (lacking of atp8), 2 ribosomal RNA genes, 42 transfer RNA genes and two ultra-long non-coding regions. The mitogenome of S. kagoshimensis is composed of 28.3% A, 34.5% T, 20.6% G and 16.6% C, showing a slight AT bias of 62.8. In addition, some peculiar patterns, like AT-rich, tandem repeats elements, are found in the largest non-coding region of S. kagoshimensis.
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Noncanonical NF-?B pathway controls the production of type I interferons in antiviral innate immunity.
Immunity
PUBLISHED: 01-13-2014
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Production of type I interferons (IFN-I) is a crucial innate immune mechanism against viral infections. IFN-I induction is subject to negative regulation by both viral and cellular factors, but the underlying mechanism remains unclear. We report that the noncanonical NF-?B pathway was stimulated along with innate immune cell differentiation and viral infections and had a vital role in negatively regulating IFN-I induction. Genetic deficiencies in major components of the noncanonical NF-?B pathway caused IFN-I hyperinduction and rendered cells and mice substantially more resistant to viral infection. Noncanonical NF-?B suppressed signal-induced histone modifications at the Ifnb promoter, an action that involved attenuated recruitment of the transcription factor RelA and a histone demethylase, JMJD2A. These findings reveal an unexpected function of the noncanonical NF-?B pathway and highlight an important mechanism regulating antiviral innate immunity.
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ROCK inhibitor Y-27632 prevents porcine oocyte maturation.
Theriogenology
PUBLISHED: 01-09-2014
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The inhibitor Y-27632 is a specific selective inhibitor of Rho-associated protein kinases (ROCKs), which are downstream effectors of Rho guanosine triphosphatease (GTPases) and regulate Rho-associated cellular functions, including actin cytoskeletal organization. Little is known regarding the effects of Y-27632 on mammalian oocyte maturation. In the present study, we investigated the effects of Y-27632 on porcine oocyte meiosis and possible regulatory mechanisms of ROCK during porcine oocyte maturation. We found that ROCK accumulated not only at spindles, but also at the cortex in porcine oocytes. Y-27632 treatment reduced ROCK expression, and inhibited porcine oocyte meiotic maturation, which might be because of the impairment of actin expression and actin-related spindle positioning. Y-27632 treatment also disrupted the formation of actin cap and cortical granule-free domain, which further confirmed a spindle positioning failure. Thus, Y-27632 has significant effects on the meiotic competence of mammalian oocytes by reducing ROCK expression, and the regulation is related to its effects on actin-mediated spindle positioning.
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A highly selective chemosensor for Al3+ based on 2-oxo-quinoline-3-carbaldehyde Schiff-base.
Spectrochim Acta A Mol Biomol Spectrosc
PUBLISHED: 01-04-2014
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A new Schiff-base ligand (1) with good fluorescence response to Al(3+), derived from 2-oxo-quinoline-3-carbaldehyde and nicotinic hydrazide, had been synthesized and investigated in this paper. Spectroscopic investigation revealed that the compound 1 exhibited a high selectivity and sensitivity toward Al(III) ions over other commonly coexisting metal ions in ethanol, and the detection limit of Al(3+) ions is at the parts per billion level. The mass spectra and Job's plot confirmed the 1:1 stoichiometry between 1 and Al(3+). Potential utilization of 1 as intracellular sensors of Al(3+) ions in human cancer (HeLa) cells was also examined by confocal fluorescence microscopy.
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3-Nitropropionic acid induces ovarian oxidative stress and impairs follicle in mouse.
PLoS ONE
PUBLISHED: 01-01-2014
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Oxidative stress induces many serious reproductive diseases in female mammals and thus poses a serious threat to reproductive health. However, the relationship between reactive oxygen species (ROS)-induced oxidative stress and follicular development, oocyte and embryo quality is not clear. The aim of this study was to investigate the effect of ovarian oxidative stress on the health of follicle and oocyte development. Female ICR mice were dosed with 3-nitropropionic acid (3-NPA) at three different concentrations (6.25, 12.5 and 25 mg/kg) and saline (control) via continuous intraperitoneal injection for 7 days. The treatment with 12.5 mg/kg reduced the weight of mouse ovaries, and significantly increased ROS levels and the activities of antioxidant enzymes--total superoxide dismutase (T-SOD), glutathione peroxidase (GPx) and catalase (CAT)--in granulosa cells and ovarian tissues, but not in other tissues (brain, liver, kidney and spleen). The same treatment significantly increased the percentage of atretic large follicles, and reduced the number of large follicles, the number of ovulated oocytes, and the capacity for early embryonic development compared with controls. It also significantly decreased the ratio of Bcl-2 to Bax, while causing an increase in the mRNA expression of (SOD2, CAT and GP X) and ROS levels in granulosa cells. Collectively, these data indicate that 3-NPA induces granulosa cell apoptosis, large follicle atresia, and an increase of ROS levels in the ovary. Therefore, we have established an in vivo model of ovarian oxidative stress for studying the mechanism of resulting damage induced by free radicals and for the screening of novel antioxidants.
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Arp2/3 complex inhibition prevents meiotic maturation in porcine oocytes.
PLoS ONE
PUBLISHED: 01-01-2014
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The Arp2/3 complex regulates actin nucleation, which is critical for a wide range of cellular processes, such as cell polarity, cell locomotion, and endocytosis. In the present study, we investigated the possible roles of the Arp2/3 complex in porcine oocytes during meiotic maturation. Immunofluorescent staining showed the Arp2/3 complex to localize mainly to the cortex of porcine oocytes, colocalizing with actin. Treatment with an Arp2/3 complex specific inhibitor, CK666, resulted in a decrease in Arp2/3 complex localization at the oocyte cortex. The maturation rate of porcine oocytes decreased significantly after CK666 treatment, concomitant with the failure of cumulus cell expansion and oocyte polar body extrusion. The fluorescence intensity of F-actin decreased in the cytoplasm, and CK666 also disrupted actin cap formation. In summary, our results illustrate that the Arp2/3 complex is required for the meiotic maturation of porcine oocytes and that actin nucleation is critical for meiotic maturation.
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Rho-GTPase effector ROCK phosphorylates cofilin in actin-meditated cytokinesis during mouse oocyte meiosis.
Biol. Reprod.
PUBLISHED: 01-01-2014
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During oocyte meiosis, a spindle forms in the central cytoplasm and migrates to the cortex. Subsequently, the oocyte extrudes a small body and forms a highly polarized egg; this process is regulated primarily by actin. ROCK is a Rho-GTPase effector that is involved in various cellular functions, such as stress fiber formation, cell migration, tumor cell invasion, and cell motility. In this study, we investigated possible roles for ROCK in mouse oocyte meiosis. ROCK was localized around spindles after germinal vesicle breakdown and was colocalized with cytoplasmic actin and mitochondria. Disrupting ROCK activity by RNAi or an inhibitor resulted in cell cycle progression and polar body extrusion failure. Time-lapse microscopy showed that this may have been due to spindle migration and cytokinesis defects, as chromosomes segregated but failed to extrude a polar body and then realigned. Actin expression at oocyte membranes and in cytoplasm was significantly decreased after these treatments. Actin caps were also disrupted, which was confirmed by a failure to form cortical granule-free domains. The mitochondrial distribution was also disrupted, which indicated that mitochondria were involved in the ROCK-mediated actin assembly. In addition, the phosphorylation levels of Cofilin, a downstream molecule of ROCK, decreased after disrupting ROCK activity. Thus, our results indicated that a ROCK-Cofilin-actin pathway regulated meiotic spindle migration and cytokinesis during mouse oocyte maturation.
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TRAF3 regulates the effector function of regulatory T cells and humoral immune responses.
J. Exp. Med.
PUBLISHED: 12-30-2013
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Regulatory T cells (Treg cells) control different aspects of immune responses, but how the effector functions of Treg cells are regulated is incompletely understood. Here we identified TNF receptor-associated factor 3 (TRAF3) as a regulator of Treg cell function. Treg cell-specific ablation of TRAF3 impaired CD4 T cell homeostasis, characterized by an increase in the Th1 type of effector/memory T cells. Moreover, the ablation of TRAF3 in Treg cells resulted in increased antigen-stimulated activation of follicular T helper cells (TFH cells), coupled with heightened formation of germinal centers and production of high-affinity IgG antibodies. Although the loss of TRAF3 did not reduce the overall frequency of Treg cells, it attenuated the antigen-stimulated production of follicular Treg cells (TFR cells). TRAF3 signaling in Treg cells was required to maintain high level expression of inducible co-stimulator (ICOS), which in turn was required for TFR cell generation and inhibition of antibody responses. These findings establish TRAF3 as a mediator of Treg cell function in the regulation of antibody responses and suggest a role for TRAF3 in mediating ICOS expression in Treg cells.
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Activation of the Transcription Factor c-Maf in T Cells Is Dependent on the CARMA1-IKK? Signaling Cascade.
Sci Signal
PUBLISHED: 12-19-2013
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The proto-oncogene c-Maf is a transcription factor that plays a critical role in the differentiation of various T helper (TH) cell subsets. The amount of c-Maf increases after stimulation of the T cell receptor (TCR), which results in the production of multiple cytokines. We showed that two essential regulators of the transcription factor nuclear factor ?B (NF-?B), the scaffold protein CARMA1 and the kinase IKK? [inhibitor of NF-?B (I?B) kinase ?], are also critical for the activation of c-Maf. Although CARMA1 deficiency did not affect the TCR-dependent increase in c-Maf abundance in T cells, CARMA1-dependent activation of the IKK complex was required for the nuclear translocation of c-Maf and its binding to the promoters of its target genes. Consistent with a role for c-Maf in the development of T follicular helper (TFH) cells, which provide help to B cells in the germinal centers of the spleen, CARMA1- or IKK?-deficient mice immunized with peptide antigen had defects in the generation of TFH cells, formation of germinal centers, and production of antigen-specific antibodies. Together, these data suggest a mechanism by which c-Maf is regulated during T cell activation and differentiation.
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Involvement of cdc25c in cell cycle alteration of a radioresistant lung cancer cell line established with fractionated ionizing radiation.
Asian Pac. J. Cancer Prev.
PUBLISHED: 12-03-2013
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Cancer patients often suffer from local tumor recurrence after radiation therapy. Cell cycling, an intricate sequence of events which guarantees high genomic fidelity, has been suggested to affect DNA damage responses and eventual radioresistant characteristics of cancer cells. Here, we established a radioresistant lung cancer cell line, A549R , by exposing the parental A549 cells to repeated ?-ray irradiation with a total dose of 60 Gy. The radiosensitivity of A549 and A549R was confirmed using colony formation assays. We then focused on examination of the cell cycle distribution between A549 and A549R and found that the proportion of cells in the radioresistant S phase increased, whereas that in the radiosensitive G1 phase decreased. When A549 and A549R cells were exposed to 4 Gy irradiation the total differences in cell cycle redistribution suggested that G2-M cell cycle arrest plays a predominant role in mediating radioresistance. In order to further explore the possible mechanisms behind the cell cycle related radioresistance, we examined the expression of Cdc25 proteins which orchestrate cell cycle transitions. The results showed that expression of Cdc25c increased accompanied by the decrease of Cdc25a and we proposed that the quantity of Cdc25c, rather than activated Cdc25c or Cdc25a, determines the radioresistance of cells.
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[Effect of flavonoids from hedysari radix on pulmonary functions of pulmonary fibrosis rat].
Zhong Yao Cai
PUBLISHED: 11-14-2013
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To study the effect of flavonoids from Hedysari Radix on pulmonary functions of pulmonary fibrosis rat and its mechanism.
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Actin nucleator Arp2/3 complex is essential for mouse preimplantation embryo development.
Reprod. Fertil. Dev.
PUBLISHED: 11-10-2013
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The Arp2/3 complex is a critical actin nucleator, which promotes actin assembly and is widely involved in a diverse range of actin-related processes such as cell locomotion, phagocytosis and the establishment of cell polarity. Previous studies showed that the Arp2/3 complex regulates spindle migration and asymmetric division during mouse oocyte maturation; however, the role of the Arp2/3 complex in early mouse embryo development is still unknown. The results of the present study show that the Arp2/3 complex is critical for cytokinesis during mouse embryo development. The Arp2/3 complex was concentrated at the cortex of each cell at the 2- to 8-cell stage and the peripheral areas of the morula and blastocyst. Inhibition of the Arp2/3 complex by the specific inhibitor CK666 at the zygote stage caused a failure in cell division; mouse embryos failed to undergo compaction and lost apical-basal polarity. The actin level decreased in the CK666-treated group, and two or more nuclei were observed within a single cell, indicating a failure of cell division. Addition of CK666 at the 8-cell stage caused a failure of blastocyst formation, and CDX2 staining confirmed the loss of embryo polarity and the failure of trophectoderm and inner cell mass formation. Taken together, these data suggest that the Arp2/3 complex may regulate mouse embryo development via its effect on cell division.
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Involvement of microRNA-335-5p in cytoskeleton dynamics in mouse oocytes.
Reprod. Fertil. Dev.
PUBLISHED: 11-10-2013
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MicroRNA is a short RNA molecule expressed in eukaryotic cells that is involved in multiple processes, including translational repression, target degradation and gene silencing. However, its specific role(s) in these processes remains largely unknown, especially in terms of germ cell development. The present study identified a microRNA, namely miR-335-5p, that is involved in mouse oocyte meiosis. MiR-335-5p was highly expressed in oocytes, but levels decreased markedly shortly after fertilisation. Microinjection of miR-335-5p or its inhibitor into oocytes resulted in a higher proportion of 2-cell-like MII oocytes and oocytes at the germinal vesicle breakdown and/or MI stage, indicating failure of asymmetric oocyte division. This may be due to regulation of actin because perturbation of miR-335-5p resulted in reduced expression of actin nucleator Daam1, a member of the Formin family. Moreover, injection of miR-335-5p or its inhibitor resulted in aberrant spindle morphology, namely an elongated spindle and multiple poles spindle. After injection of oocytes, levels of phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) decreased, suggesting that miR-335-5p may regulate spindle formation via the mitogen-activated protein kinase pathway. Overexpression and inhibition of miR-335-5p had no effect on embryo development. Together, the results of the present study indicate that miR-335-5p is a novel regulator expressed in oocytes that is involved in cytoskeleton dynamics.
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Structural Elucidation of Lignin Polymers of Eucalyptus Chips during Organosolv Pretreatment and Extended Delignification.
J. Agric. Food Chem.
PUBLISHED: 11-08-2013
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Effective delignification of lignocelluloses is a very important to guarantee the economic feasibility of organosolv-based biorefinery. Eucalyptus chips were successively subjected to organosolv pretreatment (AEOP) and extended delignification (ED) process in the present study. The effects of delignification processes were scientifically evaluated by component analysis, SEM, and CP-MAS NMR techniques. It was found that the integrated process of organosolv pretreatment and subsequent delignification resulted in an effective delignification. The fundamental chemistry of the lignin obtained after these processes was thoroughly investigated by FT-IR, multidimensional NMR ((31)P-, (13)C-, and 2D-HSQC NMR), and GPC techniques. It was observed that an extensive cleavage of aryl ether linkages, ethoxylation, and some condensation reactions occurred in AEOP process, while ?-oxidation mainly took place in alkaline hydrogen peroxide (AHP) process. It is believed that better understanding the fundamental chemistry of lignin facilitates the optimization of the delignification process. More importantly, well-defined of lignin polymers will facilitate their value-added applications in current and future biorefineries.
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MKlp2 inhibitior paprotrain affects polar body extrusion during mouse oocyte maturation.
Reprod. Biol. Endocrinol.
PUBLISHED: 10-09-2013
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Mammalian oocyte meiotic maturation involves a number of important processes, including spindle assembly and migration, cortical reorganization and polar body extrusion. Numerous proteins contribute to these processes, but it is unknown whether MKlp2 (mitotic kinesin-like protein 2; also called KIF20A), a microtubule-associated protein that regulates cytokinesis during mitosis, is involved in oocyte maturation.
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Oocyte quality in mice is affected by a mycotoxin-contaminated diet.
Environ. Mol. Mutagen.
PUBLISHED: 09-12-2013
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Mycotoxins, such as deoxynivalenol (DON), zearalenone (ZEN), and aflatoxin (AF), are commonly found in many food commodities and may impair the growth and reproductive efficiency of animals and humans. We investigated the effects of a mycotoxin-contaminated diet on mouse oocyte quality. Maize contaminated with DON (3.875 mg/kg), ZEN (1,897 ?g/kg), and AF (806 ?g/kg) was incorporated into a mouse diet at three different levels (0, 15, and 30% w/w). After 4 weeks, ovarian and germinal vesicle oocyte indices decreased in mycotoxin-fed mice. Oocytes from these mice exhibited low developmental competence with reduced germinal vesicle breakdown and polar body extrusion rates. Embryo developmental competence also showed a similar pattern, and the majority of embryos could not develop to the morula stage. Actin expression was also reduced in both the oocyte cortex and cytoplasm, which was accompanied by decreased expression of the actin nucleation factors profilin-1 and mDia1. Moreover, a large percentage of oocytes derived from mice that were fed a mycotoxin-contaminated diet exhibited aberrant spindle morphology, a loss of the cortical granule-free domain, and abnormal mitochondrial distributions, which further supported the decreased oocyte quality. Thus, our results demonstrate that mycotoxins are toxic to the mouse reproductive system by affecting oocyte quality. Environ. Mol. Mutagen., 2013. © 2013 Wiley Periodicals, Inc.
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Fractionation of bamboo culms by autohydrolysis, organosolv delignification and extended delignification: Understanding the fundamental chemistry of the lignin during the integrated process.
Bioresour. Technol.
PUBLISHED: 08-26-2013
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Bamboo (Phyllostachys pubescens) was successfully fractionated using a three-step integrated process: (1) autohydrolysis pretreatment facilitating xylooligosaccharide (XOS) production (2) organosolv delignification with organic acids to obtain high-purity lignin, and (3) extended delignification with alkaline hydrogen peroxide (AHP) to produce purified pulp. The integrated process was comprehensively evaluated by component analysis, SEM, XRD, and CP-MAS NMR techniques. Emphatically, the fundamental chemistry of the lignin fragments obtained from the integrated process was thoroughly investigated by gel permeation chromatography and solution-state NMR techniques (quantitative (13)C, 2D-HSQC, and (31)P-NMR spectroscopies). It is believed that the integrated process facilitate the production of XOS, high-purity lignin, and purified pulp. Moreover, the enhanced understanding of structural features and chemical reactivity of lignin polymers will maximize their utilizations in a future biorefinery industry.
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Fabrication of multifunctional Gd2O3/Au hybrid nanoprobe via a one-step approach for near-infrared fluorescence and magnetic resonance multimodal imaging in vivo.
Anal. Chem.
PUBLISHED: 08-21-2013
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Facile fabrication of multimodal imaging probes is highly desired for bioimaging application due to their integrated advantages of several imaging modalities. Here, we report a simple and one-step mild strategy to fabricate a multifunctional Gd2O3/Au hybrid nanoprobe. Bovine serum albumin (BSA) was used as the template in the biomineralization synthesis. The fabricated BSA-Gd2O3/Au nanoprobe showed excellent chemical stability, intense near-infrared (NIR) fluorescence, and good magnetic resonance imaging (MRI) ability. The multimodal imaging potential of the prepared multifunctional nanoprobe was demonstrated by successful NIR fluorescent and magnetic resonance blood pool imaging. Further modification of BSA-Gd2O3/Au with arginine-glycine-aspartic acid peptide c(RGDyK) (RGD) enabled the nanoprobe for targeted tumor imaging in vivo.
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A novel surgery-like strategy for droplet coalescence in microchannels.
Lab Chip
PUBLISHED: 07-24-2013
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We report an innovative and efficient surgery-like strategy for achieving the coalescence of surfactant-stabilized droplets in microchannels. As pairs of preformed droplets flow across a micro-lancet, with a suitable surface wettability, in a converging microchannel simultaneously, their surfaces are scratched by the micro-lancet, which causes temporarily local scattering of surfactants, and thus induces their coalescence by joining up their scratched wounds. Our approach shows highly controllable flexibility and stability. We demonstrate this by controlling the coalescence of emulsion droplets with different numbers and complex structures. This surgery-like strategy is totally passive and has great potential in myriad applications including micro-reaction, high-throughput injection, and multiple emulsion formation, etc.
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Structure and thermal property of alkaline hemicelluloses from steam exploded Phyllostachys pubescens.
Carbohydr Polym
PUBLISHED: 07-05-2013
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An environmentally friendly pretreatment process was developed to fractionate hemicelluloses from dried and water-immersed Phyllostachys pubescens chips by steam explosion followed with alkali and alkali/ethanol extractions. The detailed chemical and structural features of the isolated hemicellulosic fractions were comparatively investigated by HPAEC, GPC, FT-IR, (13)C NMR spectroscopies, and TGA analysis. It was found that the xylose/arabinose ratios of hemicelluloses obtained from alkali and alkali/ethanol extractions were 21.5-34.4 and 7.7-9.9, respectively, suggesting that hemicelluloses extracted with alkali had relatively lower degree of branches than those extracted with alkali/ethanol. Hemicellulosic fractions isolated from the water-immersed samples were obtained in high yields and exhibited similar compositions, which can be used as raw materials for production of value-added products. Furthermore, the hemicelluloses extracted with alkali had relatively higher molecular weight than those extracted with alkali/ethanol. In addition, an increment of incubation time resulted in a decreased thermal stability of hemicelluloses obtained from water-immersed sample.
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[Analysis of epidural hematoma formative reason and its preventive measure after anterior cervical operation].
Zhongguo Gu Shang
PUBLISHED: 06-26-2013
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To explore the risk factors,preventive measure of epidural hematoma after anterior cervical operation.
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Molecular mechanisms of asymmetric division in oocytes.
Microsc. Microanal.
PUBLISHED: 06-14-2013
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In contrast to symmetric division in mitosis, mammalian oocyte maturation is characterized by asymmetric cell division that produces a large egg and a small polar body. The asymmetry results from oocyte polarization, which includes spindle positioning, migration, and cortical reorganization, and this process is critical for fertilization and the retention of maternal components for early embryo development. Although actin dynamics are involved in this process, the molecular mechanism underlying this remained unclear until the use of confocal microscopy and live cell imaging became widespread in recent years. Information obtained through a PubMed database search of all articles published in English between 2000 and 2012 that included the phrases "oocyte, actin, spindle migration," "oocyte, actin, polar body," or "oocyte, actin, asymmetric division" was reviewed. The actin nucleation factor actin-related protein 2/3 complex and its nucleation-promoting factors, formins and Spire, and regulators such as small GTPases, partitioning-defective/protein kinase C, Fyn, microRNAs, cis-Golgi apparatus components, myosin/myosin light-chain kinase, spindle stability regulators, and spindle assembly checkpoint regulators, play critical roles in asymmetric cell division in oocytes. This review summarizes recent findings on these actin-related regulators in mammalian oocyte asymmetric division and outlines a complete signaling pathway.
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Clinical analysis of thyroid carcinoma showing thymus-like differentiation: report of 8 cases.
Int Surg
PUBLISHED: 05-25-2013
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Thyroid carcinoma showing thymus-like differentiation (CASTLE) is a kind of rare neoplasm of the thyroid gland. Because thyroid CASTLE is rare and difficult to diagnose, its clinicopathologic features have not been well defined, and no universally accepted treatment recommendation is available. We analyzed retrospectively the clinicopathologic data of 8 patients with thyroid CASTLE who underwent surgery and radiotherapy at the Shengjing Hospital of China Medical University between December 2008 and June 2012. All patients accepted radical surgery. All patients accepted postoperative radiotherapy, except one 79-year-old patient. There was no evidence of recurrence or metastasis during the follow-up period. The pattern of immunohistochemical staining was similar to that of thymic carcinoma. Six of 8 CASTLE cases expressed CD5. All 8 CASTLE patients were negatively expressed in thyroglobulin, thyroid transcription factor 1, and calcitonin. Patients with thyroid CASTLE have good outcomes after radical resection and postoperative radiotherapy. Positive CD5 immunoreactivity can contribute to diagnosis of this disease.
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Identification of genes and candidate agents associated with pancreatic cancer.
Tumour Biol.
PUBLISHED: 05-21-2013
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Pancreatic cancer is a malignant neoplasm originating from transformed cells arising in tissues forming the pancreas. A major challenge in current cancer research is biological interpretation of complexity of cancer somatic mutation profiles. It has been suggested that several molecular alterations may play important roles in pancreatic carcinogenesis. In this study, by using the GSE28735 affymetrix microarray data accessible from Gene Expression Omnibus (GEO) database, we identified differentially expressed genes (DEGs) between paired pancreatic cancer tissues and adjacent nontumor tissues, followed the protein-protein interaction of the DEGs. Our study identified thousands of DEGs involved in regulation of cell cycle and apoptosis in progression of pancreatic cancer. Sp1 was predicted to be the major regulator by transcription factors analysis. From the protein-protein interaction networks, we found that Tk1 might play an important role in the progression of pancreatic cancer. Finally, we predicted candidate agents, including tomatidine and nialamide, which may be used as drugs to treat pancreatic cancer. In conclusion, our data provide a comprehensive bioinformatics analysis of genes and pathways which may be involved in the progression of pancreatic cancer.
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Ubiquitin-specific protease 25 regulates TLR4-dependent innate immune responses through deubiquitination of the adaptor protein TRAF3.
Sci Signal
PUBLISHED: 05-16-2013
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Protein ubiquitination plays a critical role in Toll-like receptor (TLR) signaling and innate immunity. Although several E3 ubiquitin ligases have been identified downstream of TLRs, the regulation of protein deubiquitination in TLR-triggered innate immune responses is poorly understood. We identified ubiquitin-specific protease 25 (USP25) as a regulator of TLR signaling. USP25 was recruited to the TLR4 signaling complex, and it associated with the adaptor proteins tumor necrosis factor receptor-associated factor 3 (TRAF3) and TRAF6 after stimulation of TLR4 with its ligand lipopolysaccharide (LPS). USP25 specifically reversed the Lys(48)-linked ubiquitination of TRAF3 that was mediated by the E3 ubiquitin ligase cIAP2 (cellular inhibitor of apoptosis 2). Deficiency in USP25 enhanced the extent of ubiquitination of TRAF3 and accelerated its degradation after TLR4 activation, which potentiated TLR4-induced activation of NF-?B (nuclear factor ?B) and MAPK (mitogen-activated protein kinase) signaling, but inhibited activation of the transcription factor IRF3 (interferon regulatory factor 3). USP25-deficient mice exhibited increased susceptibility to LPS-induced septic shock compared to their wild-type counterparts, which was associated with enhanced production of proinflammatory cytokines and decreased production of interferon-?. Thus, by inhibiting the degradation of TRAF3 during TLR4 activation, USP25 enables a balanced innate immune response.
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Superovulation induces defective methylation in line-1 retrotransposon elements in blastocyst.
Reprod. Biol. Endocrinol.
PUBLISHED: 05-10-2013
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Series of epigenetic events happen during preimplantation development. Therefore assistant reproduction techniques (ART) have the potential to disrupt epigenetic regulation during embryo development. The purpose of this study was to investigate whether defects in methylation patterns in blastocyst due to superovulation originate from abnormal expression of Dnmts.
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Spatio-temporal analysis of type 2 diabetes mellitus based on differential expression networks.
Sci Rep
PUBLISHED: 05-08-2013
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T2DM is complex in its dynamical dependence on multiple tissues, disease states, and factors interactions. However, most existing work devoted to characterizing its pathophysiology from one static tissue, individual factors, or single state. Here we perform a spatio-temporal analysis on T2DM by developing a new form of molecular network, i.e. differential expression network (DEN), which can reflect phenotype differences at network level. Static DENs show that three tissues (white adipose, skeletal muscle, and liver) all suffer from severe inflammation and perturbed metabolism, among which metabolic functions are seriously affected in liver. Dynamical analysis on DENs reveals metabolic function changes in adipose and liver are consistent with insulin resistance (IR) deterioration. Close investigation on IR pathway identifies disease interactions, revealing that IR deterioration is earlier than that on SlC2A4 in adipose and muscle. Our analysis also provides evidence that rising of insulin secretion is the root cause of IR in diabetes.
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[Transoral plate internal fixation for treatment of instability atlas fracture].
Zhongguo Gu Shang
PUBLISHED: 04-27-2013
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To evaluate the efficacy and safety of transoral plate internal fixation for instability atlas fracture.
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Revealing the structural inhomogeneity of lignins from sweet sorghum stem by successive alkali extractions.
J. Agric. Food Chem.
PUBLISHED: 04-24-2013
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To investigate the inhomogeneity of the lignin from sweet sorghum stem, successive alkali treatments were applied to extract lignin fragments in the present study. The successive treatments released 80.3% of the original lignin from the sorghum stem. The chemical structural inhomogeneity of the isolated lignins was comparatively and comprehensively investigated by UV, FT-IR, and NMR spectra. The lignins were found to be predominantly composed of ?-O-4 aryl ether linkages, together with minor amounts of ?-?, ?-5, ?-1, and ?,?-diaryl ether linkages. In addition, hydroxycinnamic acid (mainly p-coumaric acid), which was found to be attached to lignin, was released and co-precipitated in the lignin fractions isolated in the initial extracting steps, whereas hydroxycinnamic acids (p-coumaric and ferulic acids) were not detected in the subsequently extracted lignin fractions. Moreover, the high proportion of carbon-carbon structures was potentially related to the high amounts of guaiacyl units in the lignin investigated. Thermogravimetric analysis revealed that the higher molecular weights of lignins resulted in relatively higher thermal stability, and the higher content of C-C structures in the lignin probably led to a higher "char residue". These findings suggested that the lignin fractions extracted from sweet sorghum stem by successive alkali extractions had inhomogeneous features in both chemical composition and structure.
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Environmentally friendly microwave ionic liquids synthesis of hybrids from cellulose and AgX (X=Cl, Br).
Carbohydr Polym
PUBLISHED: 04-15-2013
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The purpose of this article was to explore an environmentally friendly strategy to synthesis of biomass-based hybrids. Herein, microwave-assisted ionic liquids method was applied to fabricate the hybrids from cellulose and AgX (X=Cl, Br) using cellulose and AgNO3. The ionic liquids act simultaneously as a solvent, a microwave absorber, and a reactant. Ionic liquids provided Cl(-) or Br(-) to the synthesis of AgCl or AgBr crystals; thus no additional reactant is needed. The products are characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential thermal analysis (DTA). The cellulose-Ag/AgCl hybrid and cellulose-Ag/AgBr hybrid were also obtained by using cellulose-AgCl and cellulose-AgBr hybrids as precursors. This environmentally friendly microwave-assisted ionic liquids method is beneficial to the hybrids with high dispersion.
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Role of nucleation-promoting factors in mouse early embryo development.
Microsc. Microanal.
PUBLISHED: 04-04-2013
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During mitosis nucleation-promoting factors (NPFs) bind to the Arp2/3 complex and activate actin assembly. JMY and WAVE2 are two critical members of the NPFs. Previous studies have demonstrated that NPFs promote multiple processes such as cell migration and cytokinesis. However, the role of NPFs in development of mammalian embryos is still unknown. Results of the present study show that the NPFs JMY and WAVE2 are critical for cytokinesis during development of mouse embryos. Both JMY and WAVE2 are expressed in mouse embryos. After injection of JMY or WAVE2 siRNA, all embryos failed to develop to the morula or blastocyst stages. Moreover, using fluorescence intensity analysis, we found that the expression of actin decreased, and multiple nuclei were observed within a single cell indicating that NPFs-induced actin reduction caused the failure of cell division. In addition, injection of JMY and WAVE2 siRNA also caused ARP2 degradation, indicating that involvement of NPFs in development of mouse embryos is mainly through regulation of ARP2/3-induced actin assembly. Taken together, these data suggested that WAVE2 and JMY are involved in development of mouse embryos, and their regulation may be through a NPFs-Arp2/3-actin pathway.
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A label-free near-infrared fluorescent assay for the determination of deoxyribonuclease I activity based on malachite green/G-quadruplexes.
Analyst
PUBLISHED: 03-26-2013
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Owing to the biological and clinical significance of deoxyribonuclease I (DNase I), it is highly desirable to develop near-infrared (NIR) fluorescent assays for the determination of DNase I activity. Here we report a label-free NIR fluorescent assay for selective determination of DNase I activity based on malachite green (MG)/G-quadruplexes. In the presence of Na(+) or K(+), single stranded DNA (ssDNA) is able to form a G-quadruplex structure, thus to increase the rigidity of MG structure and result in a remarkable NIR fluorescence. As DNase I is capable of cleaving all types of DNA indiscriminately to release nucleotide products, the G-quadruplexes are cleaved into oligonucleotides in the presence of DNase I. As a result, the rigidity of MG structure is reduced, and the NIR fluorescence of the solution decreases with increase of DNase I activity, providing a useful platform for low-cost, label-free and convenient detection of DNase I activity. Under the optimum conditions, the proposed label-free NIR fluorescent assay gave a detection limit of 1 u mL(-1), and a relative standard deviation of 3.2% for eleven replicate detections of 50 u mL(-1) DNase I. The proposed assay was applied to the determination of DNase I activity in spiked human urine samples with recoveries from 99.1 to 109.0%.
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Identifying MicroRNA and mRNA expression profiles in embryonic stem cells derived from parthenogenetic, androgenetic and fertilized blastocysts.
J Genet Genomics
PUBLISHED: 03-13-2013
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MicroRNAs (miRNAs) are a class of highly conserved small non-coding RNA molecules that play a pivotal role in several cellular functions. In this study, miRNA and messenger RNA (mRNA) profiles were examined by Illumina microarray in mouse embryonic stem cells (ESCs) derived from parthenogenetic, androgenetic, and fertilized blastocysts. The global analysis of miRNA-mRNA target pairs provided insight into the role of miRNAs in gene expression. Results showed that a total of 125 miRNAs and 2394 mRNAs were differentially expressed between androgenetic ESCs (aESCs) and fertilized ESCs (fESCs), a total of 42 miRNAs and 87 mRNAs were differentially expressed between parthenogenetic ESCs (pESCs) and fESCs, and a total of 99 miRNAs and 1788 mRNAs were differentially expressed between aESCs and pESCs. In addition, a total of 575, 5 and 376 miRNA-mRNA target pairs were observed in aESCs vs. fESCs, pESCs vs. fESCs, and aESCs vs. pESCs, respectively. Furthermore, 15 known imprinted genes and 16 putative uniparentally expressed miRNAs with high expression levels were confirmed by both microarray and real-time RT-PCR. Finally, transfection of miRNA inhibitors was performed to validate the regulatory relationship between putative maternally expressed miRNAs and target mRNAs. Inhibition of miR-880 increased the expression of Peg3, Dyrk1b, and Prrg2 mRNA, inhibition of miR-363 increased the expression of Nfat5 and Soat1 mRNA, and inhibition of miR-883b-5p increased Nfat5, Tacstd2, and Ppapdc1 mRNA. These results warrant a functional study to fully understand the underlying regulation of genomic imprinting in early embryo development.
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Network biomarkers reveal dysfunctional gene regulations during disease progression.
FEBS J.
PUBLISHED: 03-01-2013
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Extensive studies have been conducted on gene biomarkers by exploring the increasingly accumulated gene expression and sequence data generated from high-throughput technology. Here, we briefly report on the state-of-the-art research and application of biomarkers from single genes (i.e. gene biomarkers) to gene sets (i.e. group or set biomarkers), gene networks (i.e. network biomarkers) and dynamical gene networks (i.e. dynamical network biomarkers). In particular, differential and dynamical network biomarkers are used as representative examples to demonstrate their effectiveness in both detecting early signals for complex diseases and revealing essential mechanisms on disease initiation and progression at a network level.
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Mycotoxin-containing diet causes oxidative stress in the mouse.
PLoS ONE
PUBLISHED: 02-26-2013
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Mycotoxins which mainly consist of Aflatoxin (AF), Zearalenone (ZEN) and Deoxynivalenol (DON) are commonly found in many food commodities. Although each component has been shown to cause liver toxicity and oxidative stress in several species, there is no evidence regarding the effect of naturally contained multiple mycotoxins on tissue toxicity and oxidative stress in vivo. In the present study, mycotoxins-contaminated maize (AF 597 µg/kg, ZEN 729 µg/kg, DON 3.1 mg/kg maize) was incorporated into the diet at three different doses (0, 5 and 20%) to feed the mice, and blood and tissue samples were collected to examine the oxidative stress related indexes. The results showed that the indexes of liver, kidney and spleen were all increased and the liver and kidney morphologies changed in the mycotoxin-treated mice. Also, the treatment resulted in the elevated glutathione peroxidase (GPx) activity and malondialdehyde (MDA) level in the serum and liver, indicating the presence of the oxidative stress. Moreover, the decrease of catalase (CAT) activity in the serum, liver and kidney as well as superoxide dismutase (SOD) activity in the liver and kidney tissue further confirmed the occurrence of oxidative stress. In conclusion, our data indicate that the naturally contained mycotoxins are toxic in vivo and able to induce the oxidant stress in the mouse.
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The root of reduced fertility in aged women and possible therapentic options: Current status and future perspects.
Mol. Aspects Med.
PUBLISHED: 02-20-2013
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It is well known that maternal ageing not only causes increased spontaneous abortion and reduced fertility, but it is also a high genetic disease risk. Although assisted reproductive technologies (ARTs) have been widely used to treat infertility, the overall success is still low. The main reasons for age-related changes include reduced follicle number, compromised oocyte quality especially aneuploidy, altered reproductive endocrinology, and increased reproductive tract defect. Various approaches for improving or treating infertility in aged women including controlled ovarian hyperstimulation with intrauterine insemination (IUI), IVF/ICSI-ET, ovarian reserve testing, preimplantation genetic diagnosis and screening (PGD/PGS), oocyte selection and donation, oocyte and ovary tissue cryopreservation before ageing, miscarriage prevention, and caloric restriction are summarized in this review. Future potential reproductive techniques for infertile older women including oocyte and zygote micromanipulations, derivation of oocytes from germ stem cells, ES cells, and iPS cells, as well as through bone marrow transplantation are discussed.
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TBP dynamics during mouse oocyte meiotic maturation and early embryo development.
PLoS ONE
PUBLISHED: 01-31-2013
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To maintain cell lineage, cells develop a mechanism which can transmit the gene activity information to the daughter cells. In mitosis, TBP (TATA-binding protein), a transcription factor which belongs to TFIID was associated with M phase chromosomes and was proved to be a bookmark for cellular memory. Although previous work showed that TBP was dispensable for mouse oocyte maturation and early embryo development, exogenous TBP protein was detected in the nuclear of oocytes and early embryos. It is still unknown whether exogenous TBP can associate with condensed chromosomes during meiosis and mouse early embryo development. In present study by the injection of GFP-tagged TBP mRNA we for the first time investigated TBP dynamics in mouse early embryos and confirmed its localization pattern in oocytes. The exogenous TBP enriched at germinal vesicle at GV stage but disappeared from the chromosomes after GVBD. Moreover, exogenous TBP was still dispersed from the chromosomes of somatic donor nuclear in oocytes by nuclear transfer (NT), further proving that oocyte has some mechanism to remove TBP. During mouse embryo development, the exogenous TBP was removed from the chromosomes of M phase zygotes, but was found to express weakly at the M phase of 2-cell. Moreover, in the blastocyst TBP was also detected at the M phase chromosomes. Overexpression of TBP caused the failure of oocyte maturation and embryo development. Our results supported the idea that TBP might be a marker for transmitting cellular memory to daughter cells.
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Peli1 promotes microglia-mediated CNS inflammation by regulating Traf3 degradation.
Nat. Med.
PUBLISHED: 01-29-2013
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Microglia are crucial for the pathogenesis of multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE). Here we show that the E3 ubiquitin ligase Peli1 is abundantly expressed in microglia and promotes microglial activation during the course of EAE induction. Peli1 mediates the induction of chemokines and proinflammatory cytokines in microglia and thereby promotes recruitment of T cells into the central nervous system. The severity of EAE is reduced in Peli1-deficient mice despite their competent induction of inflammatory T cells in the peripheral lymphoid organs. Notably, Peli1 regulates Toll-like receptor (TLR) pathway signaling by promoting degradation of TNF receptor-associated factor 3 (Traf3), a potent inhibitor of mitogen-activated protein kinase (MAPK) activation and gene induction. Ablation of Traf3 restores microglial activation and CNS inflammation after the induction of EAE in Peli1-deficient mice. These findings establish Peli1 as a microglia-specific mediator of autoimmune neuroinflammation and suggest a previously unknown signaling mechanism of Peli1 function.
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The sternocleidomastoid muscle flap for the prevention of Frey syndrome and cosmetic deformity following parotidectomy: A systematic review and meta-analysis.
Oncol Lett
PUBLISHED: 01-28-2013
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Approximately 34-86% of neoplasms of the salivary glands are located in the parotid gland and parotidectomy is the first-line treatment for parotid gland tumors. Frey syndrome and cosmetic deformity are common complications experienced by patients following parotidectomy and the sternocleidomastoid muscle flap (SCMF) is used to prevent them. Numerous studies have been performed to examine the effectiveness of the SCMF for the prevention of cosmetic deformity and Frey syndrome, however, they provide contradictory results and possess small sample sizes with consequently low statistical power. In order to evaluate the effectiveness of the SCMF for the prevention of Frey syndrome and cosmetic deformity following parotidectomy, we performed a systematic review and meta-analysis based on published randomized controlled trials (RCTs), which were identified using PubMed and CNKI databases, and references of studies up to August 2012 were included. Using these criteria, we yielded 11 RCTs. Following an independent assessment of the methodological quality of these studies and the extraction of data, a systematic review and meta-analysis was conducted. The results of the meta-analysis demonstrated that there was a significant trend towards a lower risk of objective incidence [67%; risk ratio (RR), 0.33; 95% confidence interval (CI), 0.16-0.67; P<0.01] and subjective incidence (66%; RR, 0.34; 95% CI, 0.16-0.75; P= 0.01) of Frey syndrome in the SCMF group. The sensitivity analysis also indicated that this result was significant. Due to the considerable variation between the included studies, a meta-analysis was not applicable to assess cosmetic deformity. Two RCTs demonstrated that the difference between the SCMF and no SCMF group was not statistically significant, while the other seven RCTs detected a statistically significant difference between the two groups. Publication bias was detected. In conclusion, based on currently available evidence, the use of the SCMF is benefical for the prevention of Frey syndrome, however, whether it is also benefical for cosmetic deformity remains inconclusive.
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Why to synthesize vaterite polymorph of calcium carbonate on the cellulose matrix via sonochemistry process?
Ultrason Sonochem
PUBLISHED: 01-20-2013
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Vaterite is an important biomedical material due to its features such as high specific surface area, high solubility, high dispersion, and small specific gravity. The purposes of this article were to explore the growth mechanism of vaterite on the cellulose matrix via sonochmistry process. In the work reported herein, the influences of experimental parameters on the polymorph of calcium carbonate were investigated in detail. The calcium carbonate crystals on the cellulose matrix were characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Experimental results revealed that all the reactants, solvent, and synthesis method played an important role in the polymorph of calcium carbonate. The pure phase of vaterite polymorph was obtained using Na2CO3 as reactant in ethylene glycol on the cellulose matrix via sonochmistry process. Based on the experimental results, one can conclude that the synthesis of vaterite polymorph is a system process.
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OTUD7B controls non-canonical NF-?B activation through deubiquitination of TRAF3.
Nature
PUBLISHED: 01-20-2013
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The non-canonical NF-?B pathway forms a major arm of NF-?B signalling that mediates important biological functions, including lymphoid organogenesis, B-lymphocyte function, and cell growth and survival. Activation of the non-canonical NF-?B pathway involves degradation of an inhibitory protein, TNF receptor-associated factor 3 (TRAF3), but how this signalling event is controlled is still unknown. Here we have identified the deubiquitinase OTUD7B as a pivotal regulator of the non-canonical NF-?B pathway. OTUD7B deficiency in mice has no appreciable effect on canonical NF-?B activation but causes hyperactivation of non-canonical NF-?B. In response to non-canonical NF-?B stimuli, OTUD7B binds and deubiquitinates TRAF3, thereby inhibiting TRAF3 proteolysis and preventing aberrant non-canonical NF-?B activation. Consequently, the OTUD7B deficiency results in B-cell hyper-responsiveness to antigens, lymphoid follicular hyperplasia in the intestinal mucosa, and elevated host-defence ability against an intestinal bacterial pathogen, Citrobacter rodentium. These findings establish OTUD7B as a crucial regulator of signal-induced non-canonical NF-?B activation and indicate a mechanism of immune regulation that involves OTUD7B-mediated deubiquitination and stabilization of TRAF3.
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CYP3A5*3 polymorphism and cancer risk: a meta-analysis and meta-regression.
Tumour Biol.
PUBLISHED: 01-14-2013
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CYP3A5 is a cytochrome P450 superfamily member which is involved in the metabolism of drugs, steroid hormones, and other xenobiotics. Emerging evidences suggest that CYP3A5*3 (rs776746 A>G) polymorphism may play a role in the etiology of carcinogenesis and affect an individuals susceptibility to cancer in humans, but individually published studies showed inconclusive results. This meta-analysis aimed to derive a more accurate estimation of the correlation between CYP3A5*3 polymorphism and cancer risk. A literature search of PubMed, Embase, Web of Science, and China BioMedicine databases was conducted on articles published before January 1, 2013. Seventeen case-control studies were included with a total of 7,458 cancer patients and 7,166 healthy controls. The meta-analysis results showed that CYP3A5*3 polymorphism may increase the risk of cancer, especially in acute leukemia, chronic leukemia, and colorectal cancer. However, no statistically significant associations were found in prostate cancer, liver cancer, and other cancers. Further subgroup analysis by ethnicity indicated that CYP3A5*3 polymorphism was associated with an increased risk of cancer among Asian and Caucasian populations, but not among African populations. In conclusion, the current meta-analysis suggests that CYP3A5*3 polymorphism may play an important role in the development of acute and chronic leukemia and colorectal cancer, especially among Asian and Caucasian populations.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.