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Find video protocols related to scientific articles indexed in Pubmed.
Histological and developmental study of prehierarchical follicles in geese.
Folia Biol. (Krakow)
PUBLISHED: 11-19-2014
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The development of the follicular wall and apoptosis of corresponding cells are dependent upon the stage of follicle growth and levels of endogenous hormones. However, the development and apoptosis of prehierarchical follicles in geese is insufficiently known. In order to obtain an understanding about the microstructure, development and apoptosis of prehierarchical follicles in geese, firstly, a histological method was used to investigate the morphological structure of prehierarchical follicles. Results showed that the thickness of granulosa cell layers of the follicular wall increased first, then decreased to the lowest when follicles grew to 9-10 mm in diameter, and the theca layers also thinned to the lowest thickness at the same stage. Moreover, the expression of follicle-stimulating hormone receptor (FSHR) mRNA and the enzyme activity of caspase-3 were analyzed and the results showed that the expression of FSHR was highest when follicles grew to 8-9 mm in diameter (p < 0.05); the enzyme activity of caspae-3 was the highest when follicles grew to 6-8 mm in diameter (p < 0.05). These collective findings suggested that follicles 6-10 mm in diameter were especially significant, and perhaps represent a turning point from growing follicles to dominant follicles to be selected into a hierarchical sequence or to other follicles to be degenerated during prehierarchical follicle development.
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Amide Groups Switch Selectivity: C-H Trifluoromethylation of ?,?-Unsaturated Amides and Subsequent Asymmetric Transformation.
Org. Lett.
PUBLISHED: 11-10-2014
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The first direct C-H ?-trifluoromethylation of unsubstituted or ?-alkyl-substituted ?,?-unsaturated carbonyl compounds under metal-free conditions was realized with excellent regio- and stereoselectivity as well as a very broad substrate scope. Both olefinic and allylic trifluoromethylation products are accessible with high selectivities by altering the substrate substitutions. The resultant olefinic products, namely (E)-?-trifluoromethyl (CF3) ?,?-unsaturated hydroxamic acid derivatives, served as acceptors in organocatalytic asymmetric Michael addition reactions to give hydroxamic acid derivatives bearing a chiral CF3-substituted stereocenter with high enantioselectivities.
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Compressive Sensing by Learning a Gaussian Mixture Model from Measurements.
IEEE Trans Image Process
PUBLISHED: 11-01-2014
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Compressive sensing of signals drawn from a Gaussian mixture model (GMM) admits closed-form minimum mean squared error (MMSE) reconstruction from incomplete linear measurements. An accurate GMM signal model is usually not available a priori, because it is difficult to obtain training signals that match the statistics of the signals being sensed. We propose to solve that problem by learning the signal model in situ, based directly on the compressive measurements of the signals, without resorting to other signals to train a model. A key feature of our method is that the signals being sensed are treated as random variables and are integrated out in the likelihood. We derive a maximum marginal likelihood estimator (MMLE), that maximizes the likelihood of the GMM of the underlying signals given only their linear compressive measurements. We extend the MMLE to a GMM with dominantly low-rank covariance matrices, to gain computational speedup. We report extensive experimental results on image inpainting, compressive sensing of high-speed video, and compressive hyperspectral imaging (the latter two based on real compressive cameras). The results demonstrate that the proposed methods outperform state-of-theart methods by significant margins.
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Asymmetric Direct Vinylogous Michael Additions of Allyl Alkyl Ketones to Maleimides through Dienamine Catalysis.
Org. Lett.
PUBLISHED: 10-30-2014
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A direct catalytic asymmetric ?-regioselective vinylogous Michael addition of allyl alkyl ketones to maleimides has been developed through dienamine catalysis of a simple chiral 1,2-diphenylethanediamine, giving multifunctional products in excellent enantioselectivity and with high yields. The success of this catalytic strategy relies on the unique inducing effect of deconjugated ?,?-C?C bond, which facilitates the formation of the otherwise unfavored extended dienamine species.
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Use of Auditory Evoked Potentials for Intra-Operative Awareness in Anesthesia: A Consciousness-Based Conceptual Model.
Cell Biochem. Biophys.
PUBLISHED: 10-20-2014
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Auditory evoked potentials (AEPs) have been used as a measure of the depth of anesthesia during the intra-operative process. AEPs are classically divided, on the basis of their latency, into first, fast, middle, slow, and late components. The use of auditory evoked potential has been advocated for the assessment of Intra-operative awareness (IOA), but has not been considered seriously enough to universalize it. It is because we have not explored enough the impact of auditory perception and auditory processing on the IOA phenomena as well as on the subsequent psychological impact of IOA on the patient. More importantly, we have seldom tried to look at the phenomena of IOP from the perspective of consciousness itself. This perspective is especially important because many of IOA phenomena exist in the subconscious domain than they do in the conscious domain of explicit recall. Two important forms of these subconscious manifestations of IOA are the implicit recall phenomena and post-operative dreams related to the operation. Here, we present an integrated auditory consciousness-based model of IOA. We start with a brief description of auditory awareness and the factors affecting it. Further, we proceed to the evaluation of conscious and subconscious information processing by auditory modality and how they interact during and after intra-operative period. Further, we show that both conscious and subconscious auditory processing affect the IOA experience and both have serious psychological implications on the patient subsequently. These effects could be prevented by using auditory evoked potential during monitoring of anesthesia, especially the mid-latency auditory evoked potentials (MLAERs). To conclude our model with present hypothesis, we propose that the use of auditory evoked potential should be universal with general anesthesia use in order to prevent the occurrences of distressing outcomes resulting from both conscious and subconscious auditory processing during anesthesia.
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CLDN3 inhibits cancer aggressiveness via Wnt-EMT signaling and is a potential prognostic biomarker for hepatocellular carcinoma.
Oncotarget
PUBLISHED: 10-04-2014
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Hepatocellular carcinoma (HCC) is one of the most common fatal malignancies but the molecular genetic basis of this disease remains unclear. By using genome-wide methylation profiling analysis, we identified CLDN3 as an epigenetically regulated gene in cancer. Here, we investigated its function and clinical relevance in human HCC. CLDN3 downregulation occurred in 87/114 (76.3%) of primary HCCs, where it was correlated significantly with shorter survival of HCC patients (P=0.021). Moreover, multivariate cyclooxygenase regression analysis showed that CLDN3 was an independent prognostic factor for overall survival (P=0.014). Absent expression of CLDN3 was also detected in 67% of HCC cell lines, which was significantly associated with its promoter hypermethylation. Ectopic expression of CLDN3 in HCC cells could inhibit cell motility, cell invasiveness, and tumor formation in nude mice. Mechanistic investigations suggested through downregulation of GSK3B, CTNNB1, SNAI2, and CDH2, CLDN3 could significantly suppress metastasis by inactivating the Wnt/?-catenin-epithelial mesenchymal transition (EMT) axis in HCC cells. Collectively, our findings demonstrated that CLDN3 is an epigenetically silenced metastasis suppressor gene in HCC. A better understanding of the molecular mechanism of CLDN3 in inhibiting liver cancer cell metastasis may lead to a more effective management of HCC patients with the inactivation of CLDN3.
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Straightforward installation of carbon-halogen, carbon-oxygen and carbon-carbon bonds within metal-organic frameworks (MOF) via palladium-catalysed direct C-H functionalization.
Chem. Commun. (Camb.)
PUBLISHED: 09-18-2014
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The straightforward C-H functionalization of UiO-67-dcppy materials was realized by a Pd-catalysed PSM. This novel protocol provides an efficient method for the synthesis of various functionalized MOFs, which have shown promising adsorbent ability in removing phenolic contaminates from water.
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Arenimonas maotaiensis sp. nov., isolated from freshwater.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 09-13-2014
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A translucent white-colored, gram-negative, facultative anaerobic, non-flagellated, slightly curved or curved bacterial strain, designated YT8T, was isolated from the freshwater of Maotai section of Chishui River, China. Cells were catalase- positive and oxidase-positive. Phylogenetic analyses of 16S rRNA gene sequence revealed that strain YT8T was a member of the genus Arenimonas with the similarity ranging from 93.7 to 95.0 %. The major isoprenoid quinone was ubiquinone 8 (Q-8), major polar lipids were phosphatidylethanolamine, one unidentified aminolipid, two unidentified phospholipids, and two unidentified polar lipids, while major fatty acids were iso-C15:0, iso-C14:0 and anteiso-C15:0. The DNA G+C content of strain YT8T was 66.6 mol %. Based on phenotypic, phylogenetic and genotypic features studied in this article, strain YT8T is suggested to represent a novel Arenimonas species, for which the name Arenimonas maotaiensis sp. nov. is proposed. The type strain is YT8T (= CGMCC 1.12726T = JCM 19710T).
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MicroRNA-9 promotes tumor metastasis via repressing E-cadherin in esophageal squamous cell carcinoma.
Oncotarget
PUBLISHED: 08-11-2014
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MicroRNAs (miRNAs) play a critical role in development and progression of cancers. Deregulation of MicroRNA-9 (miR-9) has been documented in many types of cancers but their role in the development of esophageal squamous cell carcinoma (ESCC) has not been studied. This study aimed to investigate the effect of miR-9 in esophageal cancer metastasis. The up-regulation of miR-9 was frequently detected in primary ESCC tumor tissue, which was significantly associated with clinical progression (P = 0.022), lymph node metastasis (P = 0.007) and poor overall survival (P < 0.001). Functional study demonstrated that miR-9 promoted cell migration and tumor metastasis, which were effectively inhibited when expression of miR-9 was silenced. Moreover, we demonstrated that miR-9 interacted with the 3'-untranslated region of E-cadherin and down-regulated its expression, which induced ?-catenin nuclear translocation and subsequently up-regulated c-myc and CD44 expression. In addition, miR-9 induced epithelial-mesenchymal transition (EMT) in ESCC, a key event in tumor metastasis. Taken together, our study demonstrates that miR-9 plays an important role in ESCC metastasis by activating ?-catenin pathway and inducing EMT via targeting E-cadherin. Our study also suggests miR-9 can be served as a new independent prognostic marker and/or as a novel potential therapeutic target for ESCC.
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p21/Cyclin E pathway modulates anticlastogenic function of Bmi-1 in cancer cells.
Int. J. Cancer
PUBLISHED: 08-01-2014
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Apart from regulating stem cell self-renewal, embryonic development and proliferation, Bmi-1 has been recently reported to be critical in the maintenance of genome integrity. In searching for novel mechanisms underlying the anticlastogenic function of Bmi-1, we observed, for the first time, that Bmi-1 positively regulates p21 expression. We extended the finding that Bmi-1 deficiency induced chromosome breaks in multiple cancer cell models. Interestingly, we further demonstrated that knockdown of cyclin E or ectopic overexpression of p21 rescued Bmi-1 deficiency-induced chromosome breaks. We therefore conclude that p21/cyclin E pathway is crucial in modulating the anticlastogenic function of Bmi-1. As it is well established that the overexpression of cyclin E potently induces genome instability and p21 suppresses the function of cyclin E, the novel and important implication from our findings is that Bmi-1 plays an important role in limiting genomic instability in cylin E-overexpressing cancer cells by positive regulation of p21.
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Video compressive sensing using Gaussian mixture models.
IEEE Trans Image Process
PUBLISHED: 07-30-2014
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A Gaussian mixture model (GMM)-based algorithm is proposed for video reconstruction from temporally compressed video measurements. The GMM is used to model spatio-temporal video patches, and the reconstruction can be efficiently computed based on analytic expressions. The GMM-based inversion method benefits from online adaptive learning and parallel computation. We demonstrate the efficacy of the proposed inversion method with videos reconstructed from simulated compressive video measurements, and from a real compressive video camera. We also use the GMM as a tool to investigate adaptive video compressive sensing, i.e., adaptive rate of temporal compression.
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Ablation of EIF5A2 induces tumor vasculature remodeling and improves tumor response to chemotherapy via regulation of matrix metalloproteinase 2 expression.
Oncotarget
PUBLISHED: 07-30-2014
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Hepatocellular carcinoma (HCC) is a highly vascularized tumor with poor clinical outcome. Our previous work has shown that eukaryotic initiation factor 5A2 (EIF5A2) over-expression enhances HCC cell metastasis. In this study, EIF5A2 was identified to be an independent risk factor for poor disease-specific survival among HCC patients. Both in vitro and in vivo assays indicated that ablation of endogenous EIF5A2 inhibited tumor angiogenesis by reducing matrix metalloproteinase 2 (MMP-2) expression. Given that MMP-2 degrades collagen IV, a main component of the vascular basement membrane (BM), we subsequently investigated the effect of EIF5A2 on tumor vasculature remodeling using complementary approaches, including fluorescent immunostaining, transmission electron microscopy, tumor perfusion assays and tumor hypoxia assays. Taken together, our results indicate that EIF5A2 silencing increases tumor vessel wall continuity, increases blood perfusion and improves tumor oxygenation. Additionally, we found that ablation of EIF5A2 enhanced the chemosensitivity of HCC cells to 5-Fluorouracil (5-FU). Finally, we demonstrated that EIF5A2 might exert these functions by enhancing MMP-2 activity via activation of p38 MAPK and JNK/c-Jun pathways.
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Differential expression and regulation of Ido2 in the mouse uterus during peri-implantation period.
In Vitro Cell. Dev. Biol. Anim.
PUBLISHED: 07-22-2014
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Ido2 is involved in tryptophan catabolism and immunity, but its physiological functions remain poorly understood. This study was undertaken to examine the expression and regulation of Ido2 gene in mouse uterus during the peri-implantation period. The results showed that Ido2 mRNA was highly expressed on day 4 of pregnancy and in the delayed implantation uterus. On days 5-8 of pregnancy, a low level of Ido2 expression was observed in the uteri. Simultaneously, Ido2 mRNA was also lowly expressed in the decidualized uterus. In the uterine stromal cells, 8-Br-cAMP could inhibit the expression of Ido2 mRNA. Moreover, Ido2 mRNA expression was gradually decreased after the stromal cells were treated with estrogen and progesterone and reached a nadir at 96 h. Further study found that overexpression of Ido2 could downregulate the expression of decidualization marker genes PRL, IGFBP1, and Dtprp under in vitro decidualization, while inhibition of Ido2 with devo-1-methyl-tryptophan (D-1-MT) could upregulate the expression of these marker genes. Under in vitro decidualization, overexpression of Ido2 could suppress the proliferation of uterine stromal cells and elevate the expression of Bax and MMP2 genes. On the contrary, Ido2 inhibitor D-1-MT could enhance the proliferation of stromal cells and expression of Bcl2 gene but decline the Bax/Bcl2 ratio. In the uterine stromal cells, estrogen and progesterone could induce the expression of Ido2 mRNA. These data indicate that Ido2 may be important for mouse embryo implantation and decidualization.
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Copper-catalyzed aminotrifluoromethylation of unactivated alkenes with (TMS)CF3: construction of trifluoromethylated azaheterocycles.
J. Org. Chem.
PUBLISHED: 07-16-2014
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The first example of a copper(I)-catalyzed intramolecular aminotrifluoromethylation of unactivated alkenes using (TMS)CF3 (trimethyl(trifluoromethyl)silane) as the CF3 source is described. A broad range of electronically and structurally varied substrates undergo convenient and step-economical transformations for the concurrent construction of a five- or six-membered ring and a C-CF3 bond toward different types of trifluoromethyl azaheterocycles. The methodology not only circumvents use of expensive electrophilic CF3 reagents or the photoredox strategy but also expands the scope to substrates that are difficult to access by the existing methods. Mechanistic studies are conducted, and a plausible mechanism is proposed.
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Regulatory role of miR-142-3p on the functional hepatic cancer stem cell marker CD133.
Oncotarget
PUBLISHED: 07-13-2014
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Tumor relapse after therapy typifies hepatocellular carcinoma (HCC) and is believed to be attributable to residual cancer stem cells (CSCs) that survive treatment. We have previously identified a CSC population derived from HCC that is characterized by CD133. Despite our growing knowledge of the importance of this subset of cells in driving HCC, the regulatory mechanism of CD133 is not known. Epigenetic changes are believed to be essential in the control of cancer and stem cells. Here, we report the epigenetic regulation of CD133 by miR-142-3p. The interaction between CD133 and miR-142-3p was identified by in silico prediction and substantiated by luciferase reporter analysis. Expression of CD133 was found to be inversely correlated with miR-142-3p in HCC clinical samples as well as in cell lines. Importantly, lower miR-142-3p expression in HCC was significantly associated with worst survival. Functional studies with miR-142-3p stably transduced in HCC cells demonstrated a diminished ability to self-renew, initiate tumor growth, invade, migrate, induce angiogenesis and resist chemotherapy. Rescue experiments whereby CD133 and miR-142-3p is simultaneously overexpressed compensated the deregulated ability of the cells to confer these features. Thus, miR-142-3p directly targets CD133 to regulate its ability to confer cancer and stem cell-like features in HCC.
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Characterization, sequencing and comparative genomic analysis of vB_AbaM-IME-AB2, a novel lytic bacteriophage that infects multidrug-resistant Acinetobacter baumannii clinical isolates.
BMC Microbiol.
PUBLISHED: 06-25-2014
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With the use of broad-spectrum antibiotics, immunosuppressive drugs, and glucocorticoids, multidrug-resistant Acinetobacter baumannii (MDR-AB) has become a major nosocomial pathogen species. The recent renaissance of bacteriophage therapy may provide new treatment strategies for combatting drug-resistant bacterial infections. In this study, we isolated a lytic bacteriophage vB_AbaM-IME-AB2 has a short latent period and a small burst size, which clear its host's suspension quickly, was selected for characterization and a complete genomic comparative study.
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Effect of ammonium pyrrolidine dithiocarbamate (PDTC) on NF-?B activation and CYP2E1 content of rats with immunological liver injury.
Pharm Biol
PUBLISHED: 06-25-2014
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Abstract Context: Ammonium pyrrolidine dithiocarbamate (PDTC) is a potent inhibitor of nuclear factor-?B (NF-?B). Recent studies have shown that NF-?B plays an essential role in the regulation of genes whose products are involved in the pathogenesis of immunological liver injury.
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miR-31 is consistently inactivated in EBV-associated nasopharyngeal carcinoma and contributes to its tumorigenesis.
Mol. Cancer
PUBLISHED: 05-24-2014
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As a distinctive type of head and neck cancers, nasopharyngeal carcinoma (NPC) is genesis from the clonal Epstein-Barr virus (EBV)-infected nasopharyngeal epithelial cells accumulated with multiple genetic lesions. Among the recurrent genetic alterations defined, loss of 9p21.3 is the most frequent early event in the tumorigenesis of EBV-associated NPC. In addition to the reported CDKN2A/p16, herein, we elucidated the role of a miRNA, miR-31 within this 9p21.3 region as NPC-associated tumor suppressor.
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Enantioselective c?h bond functionalization triggered by radical trifluoromethylation of unactivated alkene.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 05-19-2014
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An asymmetric unactivated alkene/C?H bond difunctionalization reaction for the concomitant construction of C?CF3 and C?O bonds was realized by using a Cu/Brønsted acid cooperative catalytic system, thus providing facile access to valuable chiral CF3 -containing N,O-aminals with excellent regio-, chemo-, and enantioselectivity. Mechanistic studies revealed that this reaction may proceed by an unprecedented 1,5-hydride shift involving activation of unactivated alkenes and a radical trifluoromethylation to initiate subsequent enantioselective functionalization of C?H bonds. Control experiments also suggested that chiral Brønsted acid plays multiple roles and not only controls the stereoselectivity but also increases the reaction rate through activation of Togni's reagent.
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Thyroid disease in Chinese girls with Turner syndrome.
J. Pediatr. Endocrinol. Metab.
PUBLISHED: 05-16-2014
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Abstract Aim: The aim of this study was to determine the prevalence of autoimmune thyroid disease in Turner syndrome (TS) and the association between thyroid autoantibodies (TAA), thyroid dysfunction, age, and karyotype. Methods: Sixty-nine girls with TS were divided into two groups according to being TAA-positive or TAA-negative. TAA and thyroid hormone concentrations were determined by immunochemiluminescence. Results: One third (23/69) of the girls were TAA positive, with antibody prevalence increasing with age. Of the TAA-positive girls, seven were hypothyroid and three hyperthyroid. Compared with the TAA-negative group, the girls in the TAA-positive group were significantly older (p<0.05). For those who were TAA positive, 26.3% of patients were 5-10 years old, 37.1% 10-15 years old, and 62.5% above the age of 15 years. Conclusion: Chinese girls with TS are prone to Hashimoto's thyroiditis, especially those older than 5 years, and routine thyroid testing is advocated thereafter on a yearly basis. There was no specific association between the incidence of autoimmune thyroid disease and TS karyotypes.
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PTEN-deficient tumors depend on AKT2 for maintenance and survival.
Cancer Discov
PUBLISHED: 05-16-2014
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Loss of PTEN is a common event in many cancers and leads to hyperactivation of the PI3K-AKT signaling pathway. The mechanisms by which AKT isoforms mediate signaling to phenotypes associated with PTEN inactivation in cancer have not been defined. Here, we show that AKT2 is exclusively required for PTEN-deficient prostate tumor spheroid maintenance, whereas AKT1 is dispensable. shRNA silencing of AKT2 but not AKT1 promotes regression of prostate cancer xenografts. Mechanistically, we show that AKT2 silencing upregulates p21 and the proapoptotic protein BAX and downregulates the insulin-like growth factor receptor-1. We also show that p21 is an effector of AKT2 in mediating prostate tumor maintenance. Moreover, AKT2 is also exclusively required for the maintenance and survival of other PTEN-deficient solid tumors, including breast cancer and glioblastoma. These findings identify a specific function for AKT2 in mediating survival of PTEN-deficient tumors and provide a rationale for developing therapeutics targeting AKT2.
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Alkenyl/Thiol-Derived Metal-Organic Frameworks (MOFs) by Means of Postsynthetic Modification for Effective Mercury Adsorption.
Chemistry
PUBLISHED: 05-04-2014
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The synthesis of new functionally diverse alkenyl-derived Cr-MIL-101s (MIL=material of Institute Lavoisier) was realized by a novel and convenient postsynthetic modification (PSM) protocol by means of the carbon?carbon bond-forming Mizoroki-Heck reaction. The new PSM protocol demonstrates a broad scope of substrates with excellent tolerance of functionality under mild reaction conditions. Moreover, a new metal-organic framework (MOF) that bears both alkenyl and thiol side chains prepared by means of the tandem PSM method has shown excellent adsorbent ability in removing mercury ions from water.
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Acetylcholinesterase overexpression mediated by oncolytic adenovirus exhibited potent anti-tumor effect.
BMC Cancer
PUBLISHED: 04-30-2014
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Acetylcholinesterase (AChE) mainly functions as an efficient terminator for acetylcholine signaling transmission. Here, we reported the effect of AChE on gastric cancer therapy.
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Podoplanin?positive cancer cells at the edge of esophageal squamous cell carcinomas are involved in invasion.
Mol Med Rep
PUBLISHED: 04-24-2014
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Podoplanin (PDPN) is a well established lymphatic endothelial marker and has frequently been observed in cancer cells at the edge of cancer masses. Previous studies investigating the association between PDPN expression and patient prognosis have had contradictory results. In the present study, it was hypothesized that the different locations of PDPN?positive cells may explain these varying results. The present study aimed to focus on PDPN expression at the edge of esophageal cancer cell nests. In order to analyze the clinical significance of this PDPN expression, immunohistochemistry was performed using esophageal cancer tissue microarrays. PDPN expression at the edge of the cancer cell nest was found to be significantly associated with invasion (P<0.05) and poor prognosis (P<0.001) in patients with cancer. To further investigate the role of PDPN expression in cancer cells, the PDPN gene was cloned and transfected into esophageal squamous cell carcinoma (ESCC) cell lines. PDPN expression was also knocked down using small interfering RNA. PDPN?positive cancer cells were found to exhibit invasion characteristics. Thus, PDPN expression at the edge of a cancer cell nest may indicate invasion and represent a poor prognostic factor for ESCCs.
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LCK: a new biomarker candidate for the early diagnosis of acute myocardial infarction.
Mol. Biol. Rep.
PUBLISHED: 04-03-2014
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Acute myocardial infarction (AMI) is one of the most common cardiovascular emergencies, of which the molecular pathogenesis is still not fully understood. This study aimed to explore the differentially expressed genes (DEGs) and then identify the critical genes in AMI thus screening out potential biomarkers for the early diagnosis of this serious heart disease. The gene expression data of AMI patients (GSE19339) were downloaded from gene expression omnibus database. After preprocessing with affy package, the DEGs were screened out by significance analysis of microarray (SAM) algorithm within samr package. Then function and pathway enrichment analyses of the DEGs were carried out using DAVID (database for annotation visualization and integrated discovery software) online tools. Further, the relevant genes of AMI were screened out with GENETIC_ASSOCIATION_DB_DISEASE analysis and blastp alignment. Finally, the novel genes were subjected to transcription factor and protein-protein interaction network analyses. A total of 633 DEGs, including 378 up-regulated and 255 down-regulated, were screened out between AMI patients and normal control samples. Among those genes, several important ones such as PPAR, CCL2, HMOX1 and NPR1 were demonstrated to be related to AMI. Most importantly, a novel gene LCK (lymphocyte-specific protein tyrosine kinase) was significantly differentially expressed in AMI. Further analyses showed that LCK was involved in the expression regulation of CXCL12 (chemokine (C-X-C motif) ligand 12) and the expression of LCK can be regulated by different transcription factors. In this study, we provided a new insight into the mechanism of AMI and raised LCK as an attractive marker candidate in the diagnosis of this serious heart disease.
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In situ generation of electrophilic trifluoromethylthio reagents for enantioselective trifluoromethylthiolation of oxindoles.
Org. Lett.
PUBLISHED: 04-03-2014
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An organocatalytic asymmetric trifluoromethylthiolation reaction via in situ generation of active electrophilic trifluoromethylthio species involving trichloroisocyanuric acid and AgSCF3 as a practical and easily handled electrophilic SCF3 source for CSP(3)-SCF3 bond formation was developed. Reactions with this one-pot version strategy occurred in good yields and excellent stereoselectivities to access enantiopure oxindoles bearing a SCF3-substituted quaternary chiral center. The straightforward process described here makes use of simple starting materials and proceeds under mild conditions, which will be useful in medicinal chemistry and diversity-oriented syntheses.
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High-throughput sequencing exclusively identified a novel Torque teno virus genotype in serum of a patient with fatal fever.
Virol Sin
PUBLISHED: 03-24-2014
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Torque teno virus (TTV) has been found to be prevalent world-wide in healthy populations and in patients with various diseases, but its etiological role has not yet been determined. Using high-throughput unbiased sequencing to screen for viruses in the serum of a patient with persistent high fever who died of suspected viral infection and prolonged weakness, we identified the complete genome sequence of a TTV (isolate Hebei-1). The genome of TTV-Hebei-1 is 3649 bp in length, encoding four putative open reading frames, and it has a G+C content of 49%. Genomic comparison and a BLASTN search revealed that the assembled genome of TTV-Hebei-1 represented a novel isolate, with a genome sequence that was highly heterologous to the sequences of other reported TTV strains. A phylogenetic tree constructed using the complete genome sequence showed that TTV-Hebei-1 and an uncharacterized Taiwanese strain, TW53A37, constitute a new TTV genotype. The patient was strongly suspected of carrying a viral infection and died eventually without any other possible causes being apparent. No virus other than the novel TTV was identified in his serum sample. Although a direct causal link between the novel TTV genotype infection and the patient's disease could not be confirmed, the findings suggest that surveillance of this novel TTV genotype is necessary and that its role in disease deserves to be explored.
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The genetic and epigenetic alterations in human hepatocellular carcinoma: a recent update.
Protein Cell
PUBLISHED: 03-18-2014
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Hepatocellular carcinoma (HCC) is one of the most frequent human malignancies worldwide with very poor prognosis. It is generally accepted that the progression of HCC is a long-term process with accumulation of multiple genetic and epigenetic alterations, which further lead to the activation of critical oncogenes or inactivation of tumor suppressor genes. HCC is characterized with multiple cancer hallmarks including their ability to proliferate, anti-apoptosis, invade, metastasis, as well as the emerging features such as stem cell properties and energy metabolic switch. The irreversible alterations at genetic level could be detected as early as in the pre-neoplastic stages and accumulate during cancer progression. Thus, they might account for the cancer initiating steps and further malignant transformation. In addition to genetic alterations, epigenetic alterations can affect the cancer transcriptome more extensively. Alterations in DNA methylation, histone modification, miRNAs, RNA editing, and lncRNAs might result in disrupted gene regulation networks and substantially contribute to HCC progression. In this review, the genetic and epigenetic alterations which significantly contribute to the malignant capabilities of HCC will be updated and summarized in detail. Further characterization of those critical molecular events might better elucidate the pathogenesis of HCC and provide novel therapeutic targets for treatment of this deadly disease.
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Neuroprotective effects of madecassoside against focal cerebral ischemia reperfusion injury in rats.
Brain Res.
PUBLISHED: 03-04-2014
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Madecassoside, a triterpenoid derivative isolated from Centella asiatica, exhibits anti-inflammatory and antioxidant activities. We investigated its neuroprotective effect against ischemia-reperfusion (I/R) injury in cerebral neurons in male Sprague-Dawley rats. Madecassoside (6, 12, or 24mg/kg, i.v.) was administered 1h after the start of reperfusion, and neurological deficit score and infarct volume were evaluated 24h later. Neuronal apoptosis was assessed by performing terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) staining, and pathological brain damage was estimated by performing hematoxylin and eosin staining. Serum levels of malondialdehyde, superoxide dismutase activity, reduced glutathione levels, and nitric oxide levels were also determined. mRNA and protein expression of pro-inflammatory cytokines (Interleukin-1?/6, and tumor necrosis factor-?) were measured by real-time RT-PCR and ELISA, respectively; NF-?B p65 expression was determined by western blotting. Madecassoside significantly reduced brain infarct area, resolved neurological deficit, and ameliorated neuronal apoptosis. It also significantly reduced the levels of malondialdehyde and nitric oxide, and augmented the antioxidant activity in rats subjected to cerebral I/R. Moreover, the levels of pro-inflammatory cytokines and NF-?B p65 significantly reduced after madecassoside treatment. These results indicate that madecassoside is neuroprotective and may be useful in reducing the damage caused by stroke.
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Isolation, culture and differentiation of duck (Anas platyrhynchos) preadipocytes.
Cytotechnology
PUBLISHED: 03-04-2014
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In the present study, we isolated preadipocytes from the adipose tissue of Peking duck and subsequently cultured them in vitro. Cell counting kit-8 assay was employed to establish the growth curve of duck primary preadipocytes. Meanwhile, after the cells reaching full confluency, they were induced to differentiate into mature adipocytes by the addition of a cocktail containing dexamethasone, insulin, 3-isobutyl-1-methylxanthine, and oleic acid for 8 days. Successful differentiation was demonstrated by the development of lipid droplets and the expression of key marker genes including peroxisome proliferator-activated receptor-? (PPAR?), CCAAT/enhancer binding protein-? (CEBP/?) and adipocyte fatty acid-binding protein (FABP4). Our results showed that duck primary preadipocytes began to adhere 12 h after seeding as short spindle shapes or litter triangles, which grew quickly 3 days post attachment and maintained stable after day 7. After 8 days the preadipocytes were induced to differentiate into mature adipocytes, which were stained red by oil red O. Additionally, it showed that during preadipocyte differentiation PPAR? mRNA was highly expressed at day 3, while CEBP/? and FABP4 mRNA peaked at day 5 and 8, respectively. These results indicate that we have successfully isolated and cultured Peking duck preadipocytes and successfully induced them to differentiate into mature adipocytes. This work could lay a foundation for further research into waterfowl adipogenesis.
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Increased expression of EIF5A2, via hypoxia or gene amplification, contributes to metastasis and angiogenesis of esophageal squamous cell carcinoma.
Gastroenterology
PUBLISHED: 02-18-2014
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Solid tumors often become hypoxic, leading to activation of hypoxia-response genes. We investigated the effects of overexpression of the hypoxia response genes eIF5A2 in esophageal squamous cell carcinoma (ESCC).
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Transcription factors GATA-4 and GATA-6: molecular characterization, expression patterns and possible functions during goose (Anser cygnoides) follicle development.
J. Reprod. Dev.
PUBLISHED: 02-17-2014
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The transcription factors GATA-4 and GATA-6, members of the GATA family, play an important role in ovarian cell proliferation, differentiation and apoptosis. In this study, the full-length coding sequences of goose GATA-4 and GATA-6 were cloned and characterized. GATA-4 and GATA-6 consist of 1236 and 1104 nucleotides encoding proteins with 411 and 367 amino acids, respectively. The deduced amino acid sequences of both proteins include two adjacent zinc finger domains with the distinctive form (CVNC-X17-CNAC)-X29-(CANC-X17-CNAC) and share 84.76% identity within this domain. In silico prediction together with matching of the high affinity RRXS(T)Y motif revealed that the GATA-4 protein might be phosphorylated predominantly at S(233), but no phosphorylation site was found in the GATA-6 protein. Real-time quantitative PCR analysis showed that GATA-4 and GATA-6 mRNAs were co-expressed in goose follicles, moderately expressed in granulosa cells and weakly expressed in theca cells. The expression level of GATA-4 mRNA in healthy follicles was significantly higher than in atretic follicles or postovulatory follicles (P<0.01), and the expression level of GATA-6 mRNA in healthy follicles was significantly lower than in atretic follicles or postovulatory follicles (P<0.01). The expression level of GATA-4 mRNA in granulosa cells was downregulated during follicle development; the peak of expression occurred in the 8-10 mm follicles, and the lowest expression was in the F1 follicles. GATA-6 was upregulated and reached its peak expression in the F1 follicles. These results indicate that the molecular structural differences in goose GATA-4 and GATA-6 may be related to their different roles during follicle development.
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Influence of diabetes mellitus on long-term clinical and economic outcomes after coronary artery bypass grafting.
Ann. Thorac. Surg.
PUBLISHED: 02-08-2014
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China has the most patients with diabetes mellitus (DM) in the world and, annually, approximately 1 million Chinese become diabetic. We investigated both clinical and economic outcomes in a large Chinese cohort of diabetic patients undergoing coronary artery bypass graft surgery (CABG).
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Downregulation of LGI1 promotes tumor metastasis in esophageal squamous cell carcinoma.
Carcinogenesis
PUBLISHED: 02-07-2014
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Here, we report the characterization of a candidate tumor suppressor gene leucine-rich glioma inactivated 1 (LGI1) in human esophageal squamous cell carcinoma (ESCC). Downregulation of LGI1 has been detected in approximately 50% of primary ESCCs, which was significantly associated with advanced clinical stage (P < 0.001), lymph node metastasis (P < 0.001), tumor invasion (P = 0.009) and poor disease-specific survival (P < 0.001). Functional studies found that LGI1 could inhibit cell growth, clonogenicity, cell motility and tumor formation in nude mice. Mechanistic investigations suggested that LGI1 acted through extracellular signal-regulated kinase (ERK1/2) signaling to downregulate matrix metalloproteinase (MMP)-3 expression and subsequently suppressed tumor metastasis. Taken together, our study revealed that LGI1 plays an important tumor suppressive role in the development and progression of ESCC, with possible application in clinics as a biomarker and a potential new therapeutic target.
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Impaired myocardium energetics associated with the risk for new-onset atrial fibrillation after isolated coronary artery bypass graft surgery.
Coron. Artery Dis.
PUBLISHED: 01-28-2014
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New-onset postoperative atrial fibrillation (POAF) is one of the most common complications occurring in 10-40% of patients after coronary artery bypass graft (CABG) surgery. Recent studies suggest that dysmetabolism may contribute to the pathogenesis of atrial fibrillation; however, the putative mechanism in patients undergoing CABG surgery is unknown. Peroxisome proliferator-activated receptor ? coactivator-1? (PGC-1?) has been demonstrated as a master regulator of myocardial energy metabolism, and glucose transporter 3 (GLUT3) has both a higher affinity for glucose and a much greater transport capacity compared with GLUT1, GLUT2, and GLUT4. We sought to evaluate the role of energy metabolism, especially the glucose metabolism, on patients after isolated CABG surgery.
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Direct access to ?-trifluoromethyl enones via efficient copper-catalyzed trifluoromethylation of Meyer-Schuster rearrangement.
Org. Lett.
PUBLISHED: 01-27-2014
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A novel domino copper-catalyzed trifluoromethylated Meyer-Schuster rearrangement reaction with Togni's reagent was developed, leading to ?-trifluormethyl (CF3) enone products with moderate to good yields. Furthermore, ?-CF3 enones can be transformed toward important trifluoromethyl heterocyclic motifs in a one-pot version.
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Efficient copper-catalyzed direct intramolecular aminotrifluoromethylation of unactivated alkenes with diverse nitrogen-based nucleophiles.
Chemistry
PUBLISHED: 01-25-2014
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A mild, convenient, and step-economical intramolecular aminotrifluoromethylation of unactivated alkenes with a variety of electronically distinct, nitrogen-based nucleophiles in the presence of a simple copper salt catalyst, in the absence of extra ligands, is described. Many different nitrogen-based nucleophiles (e.g., basic primary aliphatic and aromatic amines, sulfonamides, carbamates, and ureas) can be employed in this new aminotrifluoromethylation reaction. The aminotrifluoromethylation process allows straightforward access to diversely substituted CF3-containing pyrrolidines or indolines, in good to excellent yields, through a direct difunctionalization strategy from the respective acyclic starting materials. Mechanistic studies were conducted and a plausible mechanism was proposed.
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Highly enantioselective kinetic resolution of axially chiral BINAM derivatives catalyzed by a Brønsted acid.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 01-18-2014
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A highly efficient strategy for the kinetic resolution of axially chiral BINAM derivatives involving a chiral Brønsted acid-catalyzed imine formation and transfer hydrogenation cascade process was developed. The kinetic resolution provides a convenient route to chiral BINAM derivatives in high yields with excellent enantioselectivities.
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Integrative genomic analysis reveals a high frequency of LKB1 genetic alteration in Chinese lung adenocarcinomas.
J Thorac Oncol
PUBLISHED: 01-15-2014
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Liver kinase B1 (LKB1) genetic alteration in lung cancer involves not only point mutations and small deletion of several base pairs but also exonic loss. However, most of recent studies in LKB1 gene status only focus on point mutations and small deletion, and thus may underestimate the actual frequency of LKB1 genetic alteration in lung cancer. Thus, an integrative analysis of LKB1 genetic alteration is timely and important for providing a better estimate for the incidence of genetic alterations in this important tumor suppressor gene. One hundred and seven lung adenocarcinomas with more than 70% tumor have been analyzed for mutation of LKB1 as well as LKB1 large deletions detection by using multiplex ligation-dependent probe amplification analysis. These samples were also analyzed for EGFR, KRAS, HER2, BRAF, ALK, ROS1, and RET status in stepwise method. Among 107 lung adenocarcinomas analyzed, 29 (27.1%) harbored LKB1 genetic alteration. Twenty-three (21.5%) harbored LKB1 large exonic deletions and eight (7.48%) had LKB1 points mutations, two samples harbored both LKB1 large exonic deletions and point mutations. Eighty-seven samples (81.31%) harbored known driver mutations and 20 samples (18.69%) had no identifiable driver mutations. A high rate of LKB1 genetic alteration in Chinese lung adenocarcinomas is revealed by the integrative analysis of point mutation and exonic deletion. Moreover, LKB1 genetic alterations are concurrent with EGFR, KRAS, HER2, and CD74-ROS fusions.
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Metal-Free Direct Intramolecular Carbotrifluoromethylation of Alkenes to Functionalized Trifluoromethyl Azaheterocycles.
Org. Lett.
PUBLISHED: 12-18-2013
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The first example of a metal-free direct carbotrifluoromethylation of alkenes using inexpensive TMSCF3 as the CF3 source is described. The methodology not only exhibits high chemoselectivity for this transformation but also expands the substrate scope that is difficult to access by known transition-metal-catalyzed methods.
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Adenosine-to-Inosine RNA Editing Mediated by ADARs in Esophageal Squamous Cell Carcinoma.
Cancer Res.
PUBLISHED: 12-03-2013
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Esophageal squamous cell carcinoma (ESCC), the major histologic form of esophageal cancer, is a heterogeneous tumor displaying a complex variety of genetic and epigenetic changes. Aberrant RNA editing of adenosine-to-inosine (A-to-I), as it is catalyzed by adenosine deaminases acting on RNA (ADAR), represents a common posttranscriptional modification in certain human diseases. In this study, we investigated the status and role of ADARs and altered A-to-I RNA editing in ESCC tumorigenesis. Among the three ADAR enzymes expressed in human cells, only ADAR1 was overexpressed in primary ESCC tumors. ADAR1 overexpression was due to gene amplification. Patients with ESCC with tumoral overexpression of ADAR1 displayed a poor prognosis. In vitro and in vivo functional assays established that ADAR1 functions as an oncogene during ESCC progression. Differential expression of ADAR1 resulted in altered gene-specific editing activities, as reflected by hyperediting of FLNB and AZIN1 messages in primary ESCC. Notably, the edited form of AZIN1 conferred a gain-of-function phenotype associated with aggressive tumor behavior. Our findings reveal that altered gene-specific A-to-I editing events mediated by ADAR1 drive the development of ESCC, with potential implications in diagnosis, prognosis, and treatment of this disease. Cancer Res; 1-12. ©2013 AACR.
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Lithium Down-regulates Histone Deacetylase 1 (HDAC1) and Induces Degradation of Mutant Huntingtin.
J. Biol. Chem.
PUBLISHED: 10-28-2013
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Lithium is an effective mood stabilizer that has been clinically used to treat bipolar disorder for several decades. Recent studies have suggested that lithium possesses robust neuroprotective and anti-tumor properties. Thus far, a large number of lithium targets have been discovered. Here, we report for the first time that HDAC1 is a target of lithium. Lithium significantly down-regulated HDAC1 at the translational level by targeting HDAC1 mRNA. We also showed that depletion of HDAC1 is essential for the neuroprotective effects of lithium and for the lithium-mediated degradation of mutant huntingtin through the autophagic pathway. Our studies explain the multiple functions of lithium and reveal a novel mechanism for the function of lithium in neurodegeneration.
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Microfabricated glow discharge plasma (MFGDP) for ambient desorption/ionization mass spectrometry.
Anal. Chem.
PUBLISHED: 09-19-2013
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A novel ambient ionization technique for mass spectrometry, microfabricated glow discharge plasma (MFGDP), is reported. This device is made of a millimeter-sized ceramic cavity with two platinum electrodes positioned face-to-face. He or Ar plasma can be generated by a direct current voltage of several hundreds of volts requiring a total power below 4 W. The thermal plume temperature of the He plasma was measured and found to be between 25 and 80 °C at a normal discharge current. Gaseous, liquid, creamy, and solid samples with molecular weights up to 1.5 kDa could be examined in both positive and negative mode, giving limits of detection (LOD) at or below the fg/mm(2) level. The relative standard deviation (RSD) of manual sampling ranged from 10% to ~20%, while correlation coefficients of the working curve (R(2)) are all above 0.98 with the addition of internal standards. The ionization mechanisms are examed via both optical and mass spectrometry. Due to the low temperature characteristics of the microplasma, nonthermal momentum desorption is considered to dominate the desorption process.
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Par-1 regulates tissue growth by influencing hippo phosphorylation status and hippo-salvador association.
PLoS Biol.
PUBLISHED: 08-01-2013
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The evolutionarily conserved Hippo (Hpo) signaling pathway plays a pivotal role in organ size control by balancing cell proliferation and cell death. Here, we reported the identification of Par-1 as a regulator of the Hpo signaling pathway using a gain-of-function EP screen in Drosophila melanogaster. Overexpression of Par-1 elevated Yorkie activity, resulting in increased Hpo target gene expression and tissue overgrowth, while loss of Par-1 diminished Hpo target gene expression and reduced organ size. We demonstrated that par-1 functioned downstream of fat and expanded and upstream of hpo and salvador (sav). In addition, we also found that Par-1 physically interacted with Hpo and Sav and regulated the phosphorylation of Hpo at Ser30 to restrict its activity. Par-1 also inhibited the association of Hpo and Sav, resulting in Sav dephosphorylation and destabilization. Furthermore, we provided evidence that Par-1-induced Hpo regulation is conserved in mammalian cells. Taken together, our findings identified Par-1 as a novel component of the Hpo signaling network.
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Cloning, functional characterization, and expression profiles of NADPH-cytochrome P450 reductase gene from the Asiatic rice striped stem borer, Chilo suppressalis (Lepidoptera: Pyralidae).
Comp. Biochem. Physiol. B, Biochem. Mol. Biol.
PUBLISHED: 07-16-2013
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NADPH-cytochrome P450 reductase (CPR) is one of the most important components of the cytochrome P450 enzyme system. It catalyzes electron transfer from NADPH to all known P450s, thus plays central roles not only in the metabolism of exogenous xenobiotics but also in the regulation of endogenous hormones in insects. In this study, a full-length cDNA encoding of a CPR (named CsCPR) was isolated from the Asiatic rice striped stem borer, Chilo suppressalis, by using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods. The cDNA contains a 2061 bp open reading frame, which encodes an enzyme of 686 amino acid residues, with a calculated molecular mass of 77.6 kDa. The deduced peptide has hallmarks of typical CPR, including an N-terminal membrane anchor and the FMN, FAD and NADPH binding domains. The N-terminal-truncated protein fused with a 6 × His·tag was heterologously expressed in Escherichia coli Rosetta (DE3) cells and purified, specific activity and the Km values of the recombinant enzyme were determined. Tissue- and developmental stage-dependent expression of CsCPR mRNA was investigated by real-time quantitative PCR. The CsCPR mRNA was noticeably expressed in the digestive, metabolic, and olfactory organs of the larvae and adults of C. suppressalis. Our initial results would provide valuable information for further study on the interactions between CPR and cytochrome P450 enzyme systems.
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Systematic correlation between spine plasticity and the anxiety/depression-like phenotype induced by corticosterone in mice.
Neuroreport
PUBLISHED: 07-11-2013
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Unraveling the pathophysiological basis for the development of and recovery from depression is a unique challenge. Dendritic plasticity has been reported to be involved in the development of depression. We modeled an anxiety/depression-like phenotype by chronic corticosterone exposure in mice and reversed this anxiety/depression-like phenotype by long-term treatment with fluoxetine (FLX). Spine density in the hippocampus was detected by Golgi-Cox staining at five time points. The data showed that 35 days of corticosterone exposure led to a decrease in spine density in CA1, concomitant with the onset of depression. Following 25 days of treatment with FLX, the decrease in both the dendritic spine density in the hippocampus and the anxiety/depression-like phenotype induced by chronic corticosterone recovered to normal levels concomitantly. Interestingly, the total spine density changes are all mainly driven by changes in thin and stubby spines, not mushroom spines, following chronic corticosterone or FLX treatment. Our results suggest that the changes in dendritic spine density in the hippocampus may be one of the pathophysiological mechanisms underlying the development of and recovery from depression, and the neuronal plasticity of CA1 is first impaired during the development of depression.
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Two co-existing germline mutations P53 V157D and PMS2 R20Q promote tumorigenesis in a familial cancer syndrome.
Cancer Lett.
PUBLISHED: 07-08-2013
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Germline mutations are responsible for familial cancer syndromes which account for approximately 5-10% of all types of cancers. These mutations mainly occur at tumor suppressor genes or genome stability genes, such as DNA repair genes. Here we have identified a cancer predisposition family, in which eight members were inflicted with a wide spectrum of cancer including one diagnosed with lung cancer at 22years old. Sequencing analysis of tumor samples as well as histologically normal specimens identified two germline mutations co-existing in the familial cancer syndrome, the mutation of tumor suppressor gene P53 V157D and mismatch repair gene PMS2 R20Q. We further demonstrate that P53 V157D and/or PMS2 R20Q mutant promotes lung cancer cell proliferation. These two mutants are capable of promoting colony formation in soft agar as well as tumor formation in transgenic drosophila system. Collectively, these data have uncovered the important role of co-existing germline P53 and PMS2 mutations in the familial cancer syndrome development.
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Enhancement of cisplatin-based TACE by a hemoglobin-based oxygen carrier in an orthotopic rat HCC model.
Artif Cells Nanomed Biotechnol
PUBLISHED: 06-25-2013
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Objective: Hypoxic tumor cells are more resistant to standard chemotherapies. A number of studies indicated that improving oxygenation inside the tumor could serve as a potential strategy to target hypoxia-induced chemoresistance. In this study, we examined whether a hemoglobin-based oxygen carrier (OC89) could increase tumor oxygenation and thus enhance the efficiency of transarterial chemoembolization (TACE) in an orthotopic rat HCC model. Methods: Efficiency of the hemoglobin-based oxygen carrier (OC89) in improving tumor oxygenation was examined by OxyLab pO2. Sensitization of chemotherapy (cisplatin) in TACE by OC89 was evaluated in four different therapeutic regimens including cisplatin (1 mg/kg) + OC89 (0.2 g/kg), cisplatin (1 mg/kg) + OC89 (0.4 g/kg), cisplatin (3 mg/kg) + OC89 (0.2 g/kg), cisplatin (3 mg/kg) + OC89 (0.4 g/kg). For all the therapeutic regimens, a single delivery of OC89 via the tail vein was performed 1 h before TACE. Results: Compared with Ringers buffer, systemic delivery of OC89 (0.4 g/kg) attenuated tumor hypoxia (p < 0.05). Additionally, partial pressure of oxygen (pO2) fraction of low readings (0-10 mmHg) inside the tumor decreased from 74.1% to 24.6% after OC89 delivery, while pO2 fraction of high readings (15-25 mmHg) increased from 22.2% to 41.5%. When cisplatin was combined with OC89, regimen cisplatin (3 mg/kg) + OC89 (0.4 g/kg) resulted in a significant inhibition of tumor growth at Day 21 after therapy (p < 0.05). Further investigation indicated that OC89 delivery influenced anti-apoptotic and pro-apoptotic balance of the UPR pathway in the tumor. Conclusions: Our data suggest that targeting tumor hypoxia with the hemoglobin-based O2 carrier serves as a promising approach to enhance the efficacy of cisplatin-based chemotherapy in HCC.
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MicroRNA-antagonism regulates breast cancer stemness and metastasis via TET-family-dependent chromatin remodeling.
Cell
PUBLISHED: 06-17-2013
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Tumor cells metastasize to distant organs through genetic and epigenetic alterations, including changes in microRNA (miR) expression. Here we find miR-22 triggers epithelial-mesenchymal transition (EMT), enhances invasiveness and promotes metastasis in mouse xenografts. In a conditional mammary gland-specific transgenic (TG) mouse model, we show that miR-22 enhances mammary gland side-branching, expands the stem cell compartment, and promotes tumor development. Critically, miR-22 promotes aggressive metastatic disease in MMTV-miR-22 TG mice, as well as compound MMTV-neu or -PyVT-miR-22 TG mice. We demonstrate that miR-22 exerts its metastatic potential by silencing antimetastatic miR-200 through direct targeting of the TET (Ten eleven translocation) family of methylcytosine dioxygenases, thereby inhibiting demethylation of the mir-200 promoter. Finally, we show that miR-22 overexpression correlates with poor clinical outcomes and silencing of the TET-miR-200 axis in patients. Taken together, our findings implicate miR-22 as a crucial epigenetic modifier and promoter of EMT and breast cancer stemness toward metastasis.
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A disrupted RNA editing balance mediated by ADARs (Adenosine DeAminases that act on RNA) in human hepatocellular carcinoma.
Gut
PUBLISHED: 06-13-2013
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OBJECTIVE: Hepatocellular carcinoma (HCC) is a heterogeneous tumour displaying a complex variety of genetic and epigenetic changes. In human cancers, aberrant post-transcriptional modifications, such as alternative splicing and RNA editing, may lead to tumour specific transcriptome diversity. DESIGN: By utilising large scale transcriptome sequencing of three paired HCC clinical specimens and their adjacent non-tumour (NT) tissue counterparts at depth, we discovered an average of 20 007 inferred A to I (adenosine to inosine) RNA editing events in transcripts. The roles of the double stranded RNA specific ADAR (Adenosine DeAminase that act on RNA) family members (ADARs) and the altered gene specific editing patterns were investigated in clinical specimens, cell models and mice. RESULTS: HCC displays a severely disrupted A to I RNA editing balance. ADAR1 and ADAR2 manipulate the A to I imbalance of HCC via their differential expression in HCC compared with NT liver tissues. Patients with ADAR1 overexpression and ADAR2 downregulation in tumours demonstrated an increased risk of liver cirrhosis and postoperative recurrence and had poor prognoses. Due to the differentially expressed ADAR1 and ADAR2 in tumours, the altered gene specific editing activities, which was reflected by the hyper-editing of FLNB (filamin B, ?) and the hypo-editing of COPA (coatomer protein complex, subunit ?), are closely associated with HCC pathogenesis. In vitro and in vivo functional assays prove that ADAR1 functions as an oncogene while ADAR2 has tumour suppressive ability in HCC. CONCLUSIONS: These findings highlight the fact that the differentially expressed ADARs in tumours, which are responsible for an A to I editing imbalance, has great prognostic value and diagnostic potential for HCC.
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Characterization of the oncogenic function of centromere protein F in hepatocellular carcinoma.
Biochem. Biophys. Res. Commun.
PUBLISHED: 06-06-2013
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Centromere protein F (CENPF) is an essential nuclear protein associated with the centromere-kinetochore complex and plays a critical role in chromosome segregation during mitosis. Up-regulation of CENPF expression has previously been detected in several solid tumors. In this study, we aim to study the expression and functional role of CENPF in hepatocellular carcinoma (HCC). We found CENPF was frequently overexpressed in HCC as compared with non-tumor tissue. Up-regulated CENPF expression in HCC was positively correlated with serum AFP, venous invasion, advanced differentiation stage and a shorter overall survival. Cox regression analysis found that overexpression of CENPF was an independent prognosis factor in HCC. Functional studies found that silencing CENPF could decrease the ability of the cells to proliferate, form colonies and induce tumor formation in nude mice. Silencing CENPF also resulted in the cell cycle arrest at G2/M checkpoint by down-regulating cell cycle proteins cdc2 and cyclin B1. Our data suggest that CENPF is frequently overexpressed in HCC and plays a critical role in driving HCC tumorigenesis.
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Urea postmodified in a metal-organic framework as a catalytically active hydrogen-bond-donating heterogeneous catalyst.
Chem. Commun. (Camb.)
PUBLISHED: 05-30-2013
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New functionally diverse urea-derived MOF hydrogen-bond-donating heterogeneous catalysts were achieved via postsynthetic modification, which exhibit excellent catalytic activity and very broad substrate scopes for the Friedel-Crafts alkylation reactions.
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Coded aperture compressive temporal imaging.
Opt Express
PUBLISHED: 05-15-2013
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We use mechanical translation of a coded aperture for code division multiple access compression of video. We discuss the compressed videos temporal resolution and present experimental results for reconstructions of > 10 frames of temporal data per coded snapshot.
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Mitochondrial Calcium Uniporter Opener Spermine Attenuates the Cerebral Protection of Diazoxide through Apoptosis in Rats.
J Stroke Cerebrovasc Dis
PUBLISHED: 05-10-2013
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It is reported that ischemic penumbra is a dynamic process, in which irreversible necrosis in the center of ischemia propagates to the neighboring tissue over time. Recent research has indicated that mitochondrial adenosine triphosphate (ATP)-sensitive potassium channels (mitoKATP) opener diazoxide plays an important role in cerebral protection; however, the role of mitochondrial calcium uniporter (MCU) in the effect of diazoxide on penumbra and infarct core remains unclear.
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Hepatocellular carcinoma: transcriptome diversity regulated by RNA editing.
Int. J. Biochem. Cell Biol.
PUBLISHED: 04-30-2013
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Hepatocellular carcinoma (HCC) can be envisioned as a prolonged multi-stage process accumulating genetic and epigenetic changes. In the past years, DNA alterations lent us important clues to the comprehension of molecular pathways involved in HCC. However, as an increasing number of RNAs were identified to be subject to A-to-I modifications, it has become apparent that RNA editing might be the causal basis of various human diseases. Recent evidence has strengthened this notion by correlating hyper-edited AZIN1 (antizyme inhibitor 1) protein with HCC onset and the mechanisms that regulate cell transformation. As we continue to demystify it, RNA editing astonishes us with its diverse substrates, esoteric functions, elaborate machinery and complex interaction with HBV/HCV viral infection. In this review, we examine the contribution of A-to-I RNA editing to caner onset/progression and explore its potential implications for cancer treatment advances.
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Mortality risk model for heart valve surgery in China.
J. Heart Valve Dis.
PUBLISHED: 04-25-2013
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The study aim was to construct a scoring system for the prediction of early mortality in heart valve surgery patients in China, on the basis of objective risk factors.
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Microwave-induced plasma desorption/ionization source for ambient mass spectrometry.
Anal. Chem.
PUBLISHED: 04-15-2013
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A new ionization source based on microwave induced plasma was developed for ambient desorption/ionization. The microwave-induced plasma desorption/ionization source (MIPDI) was composed of a copper Surfatron microwave cavity where a fused-silica tube was centered axially. Stable nonlocal thermodynamic equilibrium plasma was generated in the quartz discharge tube when a microwave at a frequency of 2450 MHz was coupled to the microwave cavity. Analytes deposited on the surface of poly(tetrafluoroethylene) (PTFE) or quartz slide after hydrofluoric acid (HF) etching were desorbed and ionized by the plasma. The performance of the MIPDI technique was validated by the analysis of a variety of chemical substances, polymer compounds, and pharmaceutical drugs using argon or helium as the discharge gas. Protonated [M + H](+) or deprotonated [M - H](-) ions were observed in the positive or negative mode. MIPDI was also used for the analysis of compounds in a complex matrix without any sample preparation. MIPDI was also capable of analyzing liquid samples. The signal-to-noise ratio was 463 in the analysis of 9.2 ng of phenylalanine, and the limit of detection was 60 pg for phenylalanine. MIPDI could desorb and ionize analytes with a molecular weight of up to 1200, which was demonstrated by the analysis of polyethylene glycol 800 (PEG800). MIPDI has advantages of simple instrumentation, relatively high temperature, stability, and reproducibility.
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Maelstrom promotes hepatocellular carcinoma metastasis by inducing epithelial-mesenchymal transition by way of Akt/GSK-3?/Snail signaling.
Hepatology
PUBLISHED: 04-10-2013
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Amplification of 1q is one of the most frequent chromosomal alterations in human hepatocellular carcinoma (HCC). In this study we identified and characterized a novel oncogene, Maelstrom (MAEL), at 1q24. Amplification and overexpression of MAEL was frequently detected in HCCs and significantly associated with HCC recurrence (P = 0.031) and poor outcome (P = 0.001). Functional study demonstrated that MAEL promoted cell growth, cell migration, and tumor formation in nude mice, all of which were effectively inhibited when MAEL was silenced with short hairpin RNA (shRNAs). Further study found that MAEL enhanced AKT activity with subsequent GSK-3? phosphorylation and Snail stabilization, finally inducing epithelial-mesenchymal transition (EMT) and promoting tumor invasion and metastasis. In addition, MAEL up-regulated various stemness-related genes, multidrug resistance genes, and cancer stem cell (CSC) surface markers at the messenger RNA (mRNA) level. Functional study demonstrated that overexpression of MAEL increased self-renewal, chemoresistance, and tumor metastasis. Conclusion: MAEL is an oncogene that plays an important role in the development and progression of HCC by inducing EMT and enhancing the stemness of HCC. (Hepatology 2013;).
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Generation of haploid embryonic stem cells from Macaca fascicularis monkey parthenotes.
Cell Res.
PUBLISHED: 04-08-2013
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Recent success in the derivation of haploid embryonic stem cells (haESCs) from mouse via parthenogenesis and androgenesis has enabled genetic screening in mammalian cells and generation of gene-modified animals. However, whether haESCs can be derived from primates remains unknown. Here, we report the derivation of haESCs from parthenogenetic blastocysts of Macaca fascicularis monkeys. These cells, termed as PG-haESCs, are pluripotent and can differentiate to cells of three embryonic germ layers in vitro or in vivo. Interestingly, the haploidy of one monkey PG-haESC line (MPH1) is more stable compared with that of the other one (MPH2), as shown by the existence of haploid cells for more than 140 days without fluorescence-activated cell sorting (FACS) enrichment of haploid cells. Importantly, transgenic monkey PG-haESC lines can be generated by lentivirus- and piggyBac transposon-mediated gene transfer. Moreover, genetic screening is feasible in monkey PG-haESCs. Our results demonstrate that PG-haESCs can be generated from monkeys, providing an ideal tool for genetic analyses in primates.
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Characterization of CACNA2D3 as a putative tumor suppressor gene in the development and progression of nasopharyngeal carcinoma.
Int. J. Cancer
PUBLISHED: 04-04-2013
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Apart from ?-catenin accumulation, loss of 3p21 is one of the most frequent genetic alterations in numerous malignancies including nasopharyngeal carcinoma (NPC). Herein, we characterized a novel candidate tumor suppressor gene (TSG) CACNA2D3, a voltage-dependent subunit alpha 2 delta 3 of a calcium channel complex. Downregulation of CACNA2D3 was frequently detected in primary NPCs and NPC cell lines compared with their nontumorigenic counterparts. Attenuated CACNA2D3 expression may be associated with loss of heterozygosity (LOH) at intragenic single-nucleotide polymorphism sites (rs589281, rs1449325 and rs6797113) and/or epigenetic silencing by methylation and histone deacetylation. Given the extensive effects of calcium in cancer, we then investigated the tumor suppressive role and underlying mechanism of CACNA2D3 in the development and progression of NPC. CACNA2D3 was stably transfected into NPC cell lines (C666 and SUNE1) at levels comparative with the normal nasopharynx, alongside siRNA-mediated silencing in an immortalized nasopharyngeal epithelial cell line (NP69) to conduct in vivo and in vitro functional assays. Our findings show that CACNA2D3-mediated increase in intracellular calcium (Ca2+) can induce mitochondrial-mediated apoptosis and activation of NLK (through the Wnt/Ca2+ pathway) to antagonize Wnt signaling-mediated anchorage-dependent and independent cell proliferation (via CCND1 and CMYC), invasion (via MMP7) and epithelial-to-mesynchemal transition (via SNAIL). As the expression pattern of calcium channels and their degree of functionality can change with the progression of cancer, CACNA2D3 may indeed be a promising biomarker for NPC. Our study also warrants further exploration in the potential therapeutic use of existing epigenetic targeting drugs (e.g., 5-azacytidine, SAHA) to reconstitute CACNA2D3-associated tumor suppression in NPC.
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National trend in congenital heart disease mortality in China during 2003 to 2010: A population-based study.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 03-30-2013
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Previous studies suggest that mortality from congenital heart diseases (CHDs) is declining in the United States. But we do not know what the CHD mortality trend is in China, especially the rural versus urban patterns. Our study aimed to determine recent changes in death caused by CHD in China and describe CHD mortality in rural and urban Chinese populations.
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HbA1c in the diagnosis of diabetes and abnormal glucose tolerance in patients with Graves hyperthyroidism.
Diabetes Res. Clin. Pract.
PUBLISHED: 03-20-2013
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OBJECTIVE: To assess the suitability of HbA1c as a criterion for the diagnosis of diabetes in patients with Graves disease. METHODS: This study enrolled 310 patients with untreated newly diagnosed Graves disease, 208 patients with euthyroid goiter and 329 age-matched (control) subjects without thyroid disease from Fuzhou, China. The performance of HbA1c against the OGTT for diagnosing diabetes was determined. The Framingham risk score was used to assess general cardiovascular disease (CVD) risk. RESULTS: The percentage of patients with abnormal glucose metabolism as classified by HbA1c levels was lower than by OGTT criteria in patients with Graves disease-33.2% vs. 41.3% for pre-diabetes and 4.5% vs. 11.3% for diabetes, respectively. The sensitivity of HbA1c for diagnosing diabetes in patients with Graves disease was lower than in patients with euthyroid goiter and subjects without thyroid disease (34.9%, 63.2% and 60.6% respectively), while the specificity was similar (99.3%, 98.6%, 97.4%). Approximately 7.4% of patients with Graves disease diagnosed with diabetes according to OGTT criteria were misdiagnosed as not having the disease by HbA1c, much higher than that for the other two groups. Patients with Graves disease with diabetes not diagnosed with the disease by HbA1c showed a high risk for CVD. CONCLUSIONS: The low sensitivity of the HbA1c criterion underestimated the percentage of diabetes in patients with Graves disease. Patients with diabetes who were misdiagnosed as not having the disease by HbA1c were at high risk for CVD.
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Tumor suppressor in lung cancer-1 (TSLC1) mediated by dual-regulated oncolytic adenovirus exerts specific antitumor actions in a mouse model.
Acta Pharmacol. Sin.
PUBLISHED: 03-18-2013
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The tumor suppressor in lung cancer-1 (TSLC1) is a candidate tumor suppressor of lung cancer, and frequently inactivated in primary non-small cell lung cancer (NSCLC). In this study, we investigated the effects of TSLC1 mediated by a dual-regulated oncolytic adenovirus on lung cancer, and the mechanisms underlying the antitumor actions.
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Chlorbipram: A novel PDE4 inhibitor with improved safety as a potential antidepressant and cognitive enhancer.
Eur. J. Pharmacol.
PUBLISHED: 03-05-2013
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Major depressive disorder is a common, but serious, psychiatric dysfunction that affects 21% of the population worldwide. Rolipram, a first-generation phosphodiesterase-4 (PDE4) inhibitor, has been shown to have significant antidepressant and cognitive enhancement effects; however, it was unsuccessful in clinic trials because of PDE4-dependent side effects such as nausea and emesis. In this study, we investigated the neuropharmacology of the novel PDE4 inhibitor chlorbipram and the classical PDE4 inhibitor rolipram. Using antidepressant-sensitive behavioral tests, we demonstrated that the acute single administration of chlorbipram (0.075-0.6mg/kg) produced antidepressant-like effects, as evidenced by decreases in the duration of immobility in Kunming mice in the forced swim and tail suspension tests, and no significant changes in locomotor activity. Scopolamine-induced cognitive dysfunction was also significantly attenuated in the Morris water maze test after the treatment of Sprague Dawley rats with different doses of chlorbipram (0.5-1.5mg/kg). Furthermore, we evaluated the emetic potential of chlorbipram in beagle dogs. After oral administration, 0.5mg/kg rolipram showed emetic profiles in all dogs within 20 minutes, whereas chlorbipram did not induce any emesis during the 120-min observation period, even at the 1.0mg/kg dose. Together, our data suggest that chlorbipram is a novel antidepressant and cognitive enhancer with little or no emetic potency.
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ERG induces androgen receptor-mediated regulation of SOX9 in prostate cancer.
J. Clin. Invest.
PUBLISHED: 02-15-2013
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Fusion of the androgen receptor-regulated (AR-regulated) TMPRSS2 gene with ERG in prostate cancer (PCa) causes androgen-stimulated overexpression of ERG, an ETS transcription factor, but critical downstream effectors of ERG-mediating PCa development remain to be established. Expression of the SOX9 transcription factor correlated with TMPRSS2:ERG fusion in 3 independent PCa cohorts, and ERG-dependent expression of SOX9 was confirmed by RNAi in the fusion-positive VCaP cell line. SOX9 has been shown to mediate ductal morphogenesis in fetal prostate and maintain stem/progenitor cell pools in multiple adult tissues, and has also been linked to PCa and other cancers. SOX9 overexpression resulted in neoplasia in murine prostate and stimulated tumor invasion, similarly to ERG. Moreover, SOX9 depletion in VCaP cells markedly impaired invasion and growth in vitro and in vivo, establishing SOX9 as a critical downstream effector of ERG. Finally, we found that ERG regulated SOX9 indirectly by opening a cryptic AR-regulated enhancer in the SOX9 gene. Together, these results demonstrate that ERG redirects AR to a set of genes including SOX9 that are not normally androgen stimulated, and identify SOX9 as a critical downstream effector of ERG in TMPRSS2:ERG fusion-positive PCa.
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Abnormal regional body fat distribution also exists in non-obese subjects with high blood pressure.
Clin. Exp. Hypertens.
PUBLISHED: 02-12-2013
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A cross-sectional analysis was performed to explore the relationship between regional body fat distribution and blood pressure in non-obese subjects with different status of blood pressure. Dual-energy X-ray absorptiometry was performed to measure fat mass. Obesity was defined as present body fat ?25% in males and ?35% in females. The ratio of leg fat mass to total fat mass (L/T) decreased gradually while the ratio of trunk fat mass to total fat mass (Tr/T) increased gradually with the increasing blood pressure for both genders in non-obese subjects (P < .01), which was consistent with the change in obese ones; and the blood pressure status in the low Tr/T + high L/T group was better than that in the high Tr/T + low L/T group, obviously. After adjustment for confounding factors, blood pressure was still positively related with Tr/T but negatively associated with L/T in non-obese groups. A multiple linear regression analysis showed that L/T was the major negative factors of blood pressure in the non-obese population. Abnormal fat distribution also exists in non-obese subjects with high blood pressure; compared to trunk fat, leg fat may be a more important factor against blood pressure.
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Depletion of a putatively druggable class of phosphatidylinositol kinases inhibits growth of p53-null tumors.
Cell
PUBLISHED: 01-21-2013
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Here, we show that a subset of breast cancers express high levels of the type 2 phosphatidylinositol-5-phosphate 4-kinases ? and/or ? (PI5P4K? and ?) and provide evidence that these kinases are essential for growth in the absence of p53. Knocking down PI5P4K? and ? in a breast cancer cell line bearing an amplification of the gene encoding PI5P4K ? and deficient for p53 impaired growth on plastic and in xenografts. This growth phenotype was accompanied by enhanced levels of reactive oxygen species (ROS) leading to senescence. Mice with homozygous deletion of both TP53 and PIP4K2B were not viable, indicating a synthetic lethality for loss of these two genes. Importantly however, PIP4K2A(-/-), PIP4K2B(+/-), and TP53(-/-) mice were viable and had a dramatic reduction in tumor formation compared to TP53(-/-) littermates. These results indicate that inhibitors of PI5P4Ks could be effective in preventing or treating cancers with mutations in TP53.
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MicroRNA profiling during rat ventricular maturation: A role for miR-29a in regulating cardiomyocyte cell cycle re-entry.
FEBS Lett.
PUBLISHED: 01-19-2013
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Recent studies demonstrated that the mammalian heart possesses some capacity to proliferate. We observed cardiomyocyte proliferation within 4 weeks of age (P4W) in rats. We found 95 microRNAs that are differentially expressed in P4W cardiomyocytes. MicroRNA-29a was among the most highly up-regulated microRNAs in P4W cardiomyocytes. Overexpression of microRNA-29a suppressed the proliferation of H9c2 cell line. MicroRNA-29a inhibition induced cardiomyocytes to proliferate, accelerated the G1/S and G2/M transition, and up-regulated the cell cycle gene expression. Cyclin D2 (CCND2) was identified as a direct target of microRNA-29a. These findings indicate that microRNA-29a is involved in cardiomyocyte proliferation during postnatal development.
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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.