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Find video protocols related to scientific articles indexed in Pubmed.
Molecular cloning and expression pattern of duck Six1 and its preliminary functional analysis in myoblasts transfected with eukaryotic expression vector.
Indian J. Biochem. Biophys.
PUBLISHED: 10-10-2014
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Skeletal muscle development is regulated by Six1, an important myogenic transcription factor. However, the functional analysis of duck Six1 has not been reported. Here, we cloned the coding domain sequence (CDS) region of the duck Six1 gene using RT-PCR and RACE methods. Bioinformatics analysis revealed that duck Six1 CDS region comprised of 849 bp and encoded 282 amino acids and had a high degree of homology with other species, suggesting that the functions of duck Six1 gene are conserved among other animals. Real-time PCR used to determine the mRNA expression profiles of duck Six1 in different tissues and different developmental stages showed that Six1 was highly expressed in skeletal muscle and the embryonic stage. Furthermore, the eukaryotic expression vector pEGFP-duSix1 was constructed and transfected into the duck myoblasts; the MTT assay revealed an obvious increase of cell proliferation after transfection. The expression profiles of Six1, Myf5 and MyoD showed that their expression levels were significantly increased. These results together suggested that pEGFP-duSix1 vector was constructed successfully and overexpression of duck Six1 in the myoblasts could promote cell proliferation activity and significant up-regulate expression of Myf5 and MyoD.
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Follistatin could promote the proliferation of duck primary myoblasts by activating PI3K/Akt/mTOR signalling.
Biosci. Rep.
PUBLISHED: 09-10-2014
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FST (follistatin) is essential for skeletal muscle development, but the intracellular signalling networks that regulate FST-induced effects are not well defined. We sought to investigate whether FST promotes the proliferation of myoblasts through the PI3K (phosphoinositide 3-kinase)/Akt (protein kinase B)/mTOR (mammalian target of rapamycin) signalling. In the present study, we transfected the pEGFP-duFST plasmid and added PI3K and mTOR inhibitors to the medium of duck primary myoblasts. Then, we analysed the cellular phenotypic changes that occurred and analysed the expression of target genes. The results showed that FST promoted myoblast proliferation, induced the mRNA expression of PI3K, Akt, mTOR, 70-kDa ribosomal protein S6K (S6 kinase) and the protein expression of phospho-Akt (Thr308), mTOR, phospho-mTOR (serine 2448), phospho-S6K (Ser417), inhibited the mRNA expression of FoxO1, MuRF1 (muscle RING finger-1) and the protein expression of phospho-FoxO1 (Ser256). Moreover, we found that the overexpression of FST could alleviate the inhibitory effect of myoblast proliferation caused by the addition of LY294002, a PI3K inhibitor. Additionally, the overexpression of duck FST also relieved the inhibition of myoblast proliferation caused by the addition of rapamycin (an mTOR inhibitor) through PI3K/Akt/mTOR signalling. In light of the present results, we hypothesize that duck FST could promote myoblast proliferation, which is dependent on PI3K/Akt/mTOR signalling.
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Downregulation of RIP140 in hepatocellular carcinoma promoted the growth and migration of the cancer cells.
Tumour Biol.
PUBLISHED: 08-17-2014
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Hepatocellular carcinoma (HCC) is one of the most common malignancies with a poor response to chemotherapy. It is very important to identify novel diagnosis biomarkers and therapeutic targets. RIP140, a regulator of estrogen receptor, recently has been found to be involved in the tumorigenesis. However, its function in the progression of HCC remains poorly understood. Here, we found that the expression of RIP140 was downregulated in the HCC tissues. Moreover, overexpression of RIP140 in HCC cells inhibited cell proliferation and migration, while downregulation of RIP140 promoted the tumorigenicity of HCC cells in vitro and in vivo. Mechanistically, RIP140 interacted with beta-catenin and negatively regulated beta-catenin/TCF signaling. Taken together, our study suggests the suppressive roles of RIP140 in the pathogenesis of HCC.
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[Assessment of positive end-expiratory pressure induced lung volume change by ultrasound in mechanically ventilated patients].
Zhonghua Jie He He Hu Xi Za Zhi
PUBLISHED: 07-12-2014
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To investigate the value of lung ultrasound for assessing positive end-expiratory pressure (PEEP) -induced lung volume change in mechanically ventilated patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) .
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Bifurcation and oscillation in a time-delay neural mass model.
Biol Cybern
PUBLISHED: 06-17-2014
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The neural mass model developed by Lopes da Silva et al. simulates complex dynamics between cortical areas and is able to describe a limit cycle behavior for alpha rhythms in electroencephalography (EEG). In this work, we propose a modified neural mass model that incorporates a time delay. This time-delay model can be used to simulate several different types of EEG activity including alpha wave, interictal EEG, and ictal EEG. We present a detailed description of the model's behavior with bifurcation diagrams. Through simulation and an analysis of the influence of the time delay on the model's oscillatory behavior, we demonstrate that a time delay in neuronal signal transmission could cause seizure-like activity in the brain. Further study of the bifurcations in this new neural mass model could provide a theoretical reference for the understanding of the neurodynamics in epileptic seizures.
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Epileptic EEG classification based on kernel sparse representation.
Int J Neural Syst
PUBLISHED: 03-27-2014
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The automatic identification of epileptic EEG signals is significant in both relieving heavy workload of visual inspection of EEG recordings and treatment of epilepsy. This paper presents a novel method based on the theory of sparse representation to identify epileptic EEGs. At first, the raw EEG epochs are preprocessed via Gaussian low pass filtering and differential operation. Then, in the scheme of sparse representation based classification (SRC), a test EEG sample is sparsely represented on the training set by solving l1-minimization problem, and the represented residuals associated with ictal and interictal training samples are computed. The test EEG sample is categorized as the class that yields the minimum represented residual. So unlike the conventional EEG classification methods, the choice and calculation of EEG features are avoided in the proposed framework. Moreover, the kernel trick is employed to generate a kernel version of the SRC method for improving the separability between ictal and interictal classes. The satisfactory recognition accuracy of 98.63% for ictal and interictal EEG classification and for ictal and normal EEG classification has been achieved by the kernel SRC. In addition, the fast speed makes the kernel SRC suit for the real-time seizure monitoring application in the near future.
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Five novel variants of GPR103 and their expression in different tissues of goose (Anser cygnoides).
Comp. Biochem. Physiol. B, Biochem. Mol. Biol.
PUBLISHED: 02-23-2014
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GPR103 plays an important role in various tissues, while little information is available about the alternative splicing (AS) of its mRNA. In the present study, we used genomic PCR to identify the partial genomic locus of goose (Anser cygnoides) GPR103 and rapid amplification of cDNA ends (RACE)-PCR to identify five GPR103 variants, including the full-length variant (aGPR103-n) and four alternatively spliced variants (aGPR103-va, -vb, -vc and -vd). Sequence analysis showed that aGPR103-va and -vd are less likely to undergo nonsense-mediated mRNA decay, suggesting that they may be translated into truncated proteins. Quantitative real-time PCR (qRT-PCR) analysis revealed that the five variants are widely distributed in the brain and peripheral tissues of geese and show specific expression patterns. Thus, we here provide the first account of the GPR103 genomic locus and illustrate its transcriptional diversity and widespread distribution in geese.
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Role of leptin in the regulation of sterol/steroid biosynthesis in goose granulosa cells.
Theriogenology
PUBLISHED: 02-21-2014
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Leptin is critical for reproductive endocrinology. The aim of this study is to assess the expression patterns of leptin receptor (Lepr) during ovarian follicle development and to reveal the mechanism by which leptin affects steroid hormone secretion in goose granulosa cells. Transcripts of Lepr were ubiquitous in all tested tissues, with pituitary and adrenal glands being the predominant sites. Goose ovarian follicles were divided into several groups by diameter including prehierarchical (4 to 6, 6 to 8, and 8 to 10 mm) and hierarchical (F5-F1) follicles. Lepr gene expression was significantly higher in granulosa cells than in theca cells from follicles of 4 to 8 mm in diameter. Expression of Lepr in granulosa cells decreased gradually as follicles developed, with fluctuating expression in F5 and F3 follicles. Lepr mRNA in theca cells underwent a slight decrease from the 6- to 8-mm cohorts to F5 follicle and then exhibited a transient increase and declined later. In vitro experiments in cultured goose granulosa cells showed that estradiol release was significantly stimulated, whereas progesterone increased slightly and testosterone decreased dramatically after leptin treatment. In accordance with the data for steroids, expression of Lepr, Srebp1, Cyp51, StAR, and Cyp19a1 were induced by the addition of leptin, and the concomitant changes in Hmgcs1, Dhcr24, Cyp11a1, 17?-hsd, Cyp17, and 3?-hsd gene expression were seen. These results suggested that leptin is involved in the development of goose ovarian follicles, and leptin's effect on steroid hormone secretion could be due to altered sterol/steroidogenic gene expression via interaction with its receptor.
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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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Molecular cloning, expression profile and transcriptional modulation of two splice variants of very low density lipoprotein receptor during ovarian follicle development in geese (Anser cygnoide).
Anim. Reprod. Sci.
PUBLISHED: 02-13-2014
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Very low density lipoprotein receptor (VLDLR)-mediated endocytosis of plasma lipoproteins into the ovary is essential for ovarian follicle development. Two splice variants of VLDLR have been identified in several species, yet little is known about their distinctive roles in ovarian developing follicles. In the present study, the full-length cDNAs of two splice isoforms of VLDLR were obtained from geese (Anser cygnoide) ovaries using the RACE method. The longer isoform (TypeI VLDLR) is 3141bp and contains five conserved structural domains, while the other (TypeII VLDLR) lacks 90bp encoding for the O-linked sugar domain. TypeII VLDLR was predominantly expressed in the ovary, with greater amounts of mRNA in theca and granulosa cells from early stages of follicle development but decreased during vitellogenesis. However, there was minimal expression of the TypeI VLDLR gene in theca cells and expression was almost undetectable in granulosa cells throughout follicle development. Yolk VLDL concentrations decreased as stage of development advanced while yolk triglyceride and cholesterol concentrations increased in a follicular size-dependent manner. The significant correlations between transcripts of TypeII VLDLR and yolk lipids supported its important role on yolk lipid deposition. In addition, in vitro experiments suggested that exogenous cholesterol, 25-hydroxycholesterol and mevinolin (a highly potent competitive inhibitor of HMG-CoA) treatment could significantly alter TypeII VLDLR gene expression in granulosa cells from both pre-hierarchical and pre-ovulatory follicles. Collectively, data from the present study indicate that TypeII VLDLR is more important for the transport of plasma lipoproteins into developing follicles than TypeI VLDLR, and provide new evidence about the influence of steroids in modulating VLDLR gene expression in ovarian cells.
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Diagnostic accuracy of serum HE4, CA125 and ROMA in patients with ovarian cancer: a meta-analysis.
Tumour Biol.
PUBLISHED: 01-18-2014
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CA125, human epididymis secretary protein 4 (HE4) and the Risk of Ovarian Malignancy Algorithm (ROMA) could be used for diagnosing ovarian cancer (OCa). However, it has not been conclusively determined which of these markers yields the best diagnostic accuracy. Therefore, we conducted a meta-analysis to evaluate the diagnostic value of these markers. We systematically searched the PubMed and ScienceDirect databases and identified 32 studies that evaluated the role of CA125, HE4 and ROMA in diagnosing OCa. The bivariate random-effects approach was used to calculate the pooled estimates by considering the heterogeneity of major related parameters such as the menopausal status, International Federation of Gynecology and Obstetrics stages, detection method and blinded design. Three tests yielded similar discriminatory performances in the OCa diagnosis (AUC [95 % CI]-0.89 [0.86-0.92] for HE4; 0.87 [0.84-0.90] for CA125; 0.91 [0.88-0.93] for ROMA). HE4 yielded a higher specificity than CA125 and ROMA (HE4 93.60 [90.00-95.90]?>CA125 82.10 [76.60-86.50] and ROMA 82.40 [77.40-86.50]), especially in the premenopausal subgroup (HE4 93.80 [88.40-96.80]?>CA125 76.30 [63.30-85.70] and ROMA 85.10 [80.40-88.80]). In contrast, CA125 and ROMA performed significantly better in the postmenopausal subgroup than in the premenopausal subgroup (AUC [95 % CI]-CA125-premenopausal 0.85 [0.82-0.88]
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Effects of the regulation of follistatin mRNA expression by IGF-1 in duck (Anas platyrhynchos) skeletal muscle.
Growth Horm. IGF Res.
PUBLISHED: 01-17-2014
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The IGF-1 and TGF-? pathways have been shown to be involved in regulating muscle development. Many mediators that are associated with the regulation of muscle development have been found to participate in the cross-talk between these two pathways. To research the relationships between IGF-1 and the follistatin-mediated TGF-? pathways in duck skeletal muscle development, a series of studies were conducted. The results showed that follistatin had similar expression patterns to IGF-1 during duck embryonic muscle development. The in ovo feeding of IGF-1 to duck eggs was shown to increase follistatin expression in the duck skeletal muscle. Thus, IGF-1 may induce the mRNA expression of follistatin. These results suggest that follistatin may be a key regulator of multiple signaling cascades responding to the cross-talk between the IGF-1 and TGF-? pathways.
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Molecular characterization, tissue distribution, and expression of two ovarian Dicer isoforms during follicle development in goose (Anser cygnoides).
Comp. Biochem. Physiol. B, Biochem. Mol. Biol.
PUBLISHED: 01-09-2014
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Dicer plays a key role in the biogenesis of microRNAs and small interfering RNAs, which control the coordinated expression of multiple of genes during follicle development. In this study, the cDNAs encoding two Dicer isoforms (gDicer-a and gDicer-b, respectively) were isolated and cloned from goose ovary using RT-PCR. This is the first time a new Dicer splice variant has been characterized at the molecular level in vertebrates. Sequence analysis indicated that both of the two isoforms consist of seven conserved functional domains, where gDicer-b lacks a linker sequence between DEAD box and helicase C domain composed of 158 amino acids. Each domain of gDicer-a/gDicer-b showed higher than 89.5% identity to corresponding domain of Dicers from chicken, human, and mouse. The ubiquity of transcripts of gDicer-a/gDicer-b was found in all tested tissues by real time PCR with the pituitary, oviduct, and hypothalamus being the predominant site of expression of gDicer-a. A similar expression profile of the gDicer-a/gDicer-b mRNAs was found during follicle development. The abrupt changes in transcripts of gDicer in 2-4mm, 9-10mm, F5, and F1 follicles support its participation in the process of follicle recruitment, selection, dominance, and ovulation. However, high mRNA levels of gDicer-b and caspase-3 were detectable in atretic and post-ovulatory follicles, where expression of gDicer-a was considerably low. These findings suggest that gDicer is required for follicle development, and structural differences in the helicase domain of two gDicer isoforms might contribute to their different roles in controlling granulosa cell apoptosis.
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Replication study of ESCC susceptibility genetic polymorphisms locating in the ADH1B-ADH1C-ADH7 cluster identified by GWAS.
PLoS ONE
PUBLISHED: 01-01-2014
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China was one of the countries with highest esophageal squamous cell carcinoma (ESCC) incidence and mortality worldwide. Alcohol drinking has been identified as a major environmental risk-factor related to ESCC. The alcohol dehydrogenase (ADH) family are major enzymes involved in the alcohol-metabolizing pathways, including alcohol dehydrogenase 1B (ADH1B) and ADH1C. Interestingly, ADH1B and ADH1C genes locate tandemly with ADH7 in a genomic segment as a gene cluster, and are all polymorphic. Several ESCC susceptibility single nucleotide polymorphisms (SNPs) of the ADH1B-ADH1C-ADH7 cluster have been identified previously through a genome-wide association study (GWAS). In the study, we examined the association between five ADH1B-ADH1C-ADH7 cluster SNPs (rs1042026, rs17033, rs1614972, rs1789903 and rs17028973) and risk of developing ESCC. Genotypes were determined in two independent case-control sets from two regions of China. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by logistic regression. Our data demonstrated that these ADH1B-ADH1C-ADH7 cluster SNPs confer susceptibility to ESCC in these two case-control sets, which were consistent to results of the previous GWAS.
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Refractive error and risk of early or late age-related macular degeneration: a systematic review and meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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To summarize relevant evidence investigating the associations between refractive error and age-related macular degeneration (AMD).
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Comparison of ictal and interictal EEG signals using fractal features.
Int J Neural Syst
PUBLISHED: 09-18-2013
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The feature analysis of epileptic EEG is very significant in diagnosis of epilepsy. This paper introduces two nonlinear features derived from fractal geometry for epileptic EEG analysis. The features of blanket dimension and fractal intercept are extracted to characterize behavior of EEG activities, and then their discriminatory power for ictal and interictal EEGs are compared by means of statistical methods. It is found that there is significant difference of the blanket dimension and fractal intercept between interictal and ictal EEGs, and the difference of the fractal intercept feature between interictal and ictal EEGs is more noticeable than the blanket dimension feature. Furthermore, these two fractal features at multi-scales are combined with support vector machine (SVM) to achieve accuracies of 97.58% for ictal and interictal EEG classification and 97.13% for normal, ictal and interictal EEG classification.
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Role of mammalian sirtuin 1 (SIRT1) in lipids metabolism and cell proliferation of goose primary hepatocytes.
Mol. Cell. Endocrinol.
PUBLISHED: 05-10-2013
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Our result showed in the fatty liver formation induced-by overfeeding goose, it was accompanied by an activation of mammalian target of rapamycin (mTOR) pathway and cell proliferation. Recent studies have suggested a crucial role for mammalian sirtuin 1 (SIRT1) in regulating lipid metabolism and cell proliferation, so we hypothesize that resveratrol -activated and nicotinamide -inhibited SIRT1 acts goose hepatocellular lipid metabolism and cell proliferation by mTOR signal pathway. Here we show that both resveratrol and nicotinamide could evidently affect the DNA synthesis rate, the lipids accumulation, the mRNA level and protein content of genes involved in the lipids metabolism, mTOR signal pathway, and the cell cycle progression of goose primary hepatocytes. Moreover, rapamycin decreased the effect of nicotinamide on lipids accumulation and cell proliferation. These findings suggest that SIRT1 functions as a regulator for mTOR signaling and plays an essential role in the regulation of hepatocyte lipid metabolism and cell proliferation.
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Functional polymorphisms in FAS and FASL contribute to risk of squamous cell carcinoma of the larynx and hypopharynx in a Chinese population.
Gene
PUBLISHED: 04-01-2013
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Accumulating evidences indicate that the functional FAS-1377G>A, -670A>G and FASL-844T>C polymorphisms affect the risk of several kinds of cancers. However, their roles in the development of larynx and hypopharynx squamous cell carcinoma (SCC) were still unknown in the Chinese. In the current study, we examined whether these functional genetic variants were associated with the risk of larynx and hypopharynx squamous SCC in a Han Chinese population. The FAS and FASL polymorphisms were genotyped in 300 patients with laryngeal and hypopharyngeal SCC and 300 control subjects by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Logistic regression analysis revealed that subjects carrying the FASL-844CT or TT genotype had a significantly decreased risk of developing laryngeal and hypopharyngeal SCC [odds ratio (OR)=0.69; 95% confidence interval (CI)=0.51-0.93; P=0.016; or, OR=0.41; 95% CI=0.20-0.86; P=0.009] compared with those carrying the CC genotype. Joint gene-smoking and gene-drinking effects were also observed, with the OR of CC genotype for smokers or drinkers were 5.15 (95%CI=3.24-8.97) or 12.52 (95%CI=7.31-22.47), respectively. Therefore, the FASL-844T>C polymorphism is associated with genetic susceptibility of developing laryngeal and hypopharyngeal SCC in a Han Chinese population.
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Primary tracheobronchial mucoepidermoid carcinoma--a retrospective study of 32 patients.
World J Surg Oncol
PUBLISHED: 02-24-2013
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This retrospective study was designed to investigate the clinical characteristics, diagnosis, treatment and prognosis of primary tracheobronchial mucoepidermoid carcinoma (MEC).
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The effects of endoplasmic reticulum stress response on duck decorin stimulate myotube hypertrophy in myoblasts.
Mol. Cell. Biochem.
PUBLISHED: 01-30-2013
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Decorin inhibits the transforming growth factor superfamily to stimulate skeletal muscle hypertrophy. The endoplasmic reticulum (ER) plays a crucial role in the synthesis and folding of proteins. The disruption of ER homeostasis affects protein folding and causes ER stress, which is associated with protein synthesis in muscle cells. The purpose of this study was to establish the mechanism by which decorin promotes myoblast proliferation and myotube hypertrophy as mediated by an ER stress-related pathway. Duck myoblasts were incubated for 24 h with tunicamycin. Our results show that tunicamycin triggered ER stress in myoblasts and led to an increase in protein synthesis via a decorin-dependent pathway. We then transfected the decorin gene into duck myoblasts in vitro, and the results demonstrated that overexpression of duck decorin increased myogenic determination factor and follistatin expression and decreased myogenin and myostatin expression. Moreover, the results demonstrated that overexpression of duck decorin led to higher expression of ER stress marker genes. This increased expression trend can be alleviated in vitro by 4-PBA, which is a chemical chaperone that inhibits palmitate-induced ER stress. Collectively, our data show that duck decorin promotes myoblast proliferation mediated by an ER stress-related pathway.
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Polymorphism of follicle stimulating hormone beta (FSH?) subunit gene and its association with litter traits in giant panda.
Mol. Biol. Rep.
PUBLISHED: 01-20-2013
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The different SSCP patterns of the follicle stimulating hormone beta (FSH?) gene amplified by three pairs of primers were sequenced. Comparisons among the three nucleotide sequences of three genotypes indicated that three base substitutions (A213T, A91G, and A89C) were detected in FSH? gene, which A213T substitution led to one amino acids mutation (Lys > Met), and the other two substitutions were synonymous mutations. The AA, AB and BB genotypes patterns obtained by FSH? primer1 had evident relation with the litter traits, but the SSCP genotypes patterns obtained by FSH? primer2 and primer3 had no evident relation with the litter traits in giant panda. The giant panda with AA and AB genotype had the largest litter size and multiparity rate compared with the BB genotypes (P < 0.05). We speculated that the giant pandas with the A allele have better litter traits than those with the B allele.
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Improvement of hypoxia-ischemia-induced white matter injury in immature rat brain by ethyl pyruvate.
Neurochem. Res.
PUBLISHED: 01-11-2013
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Ethyl pyruvate (EP) has been reported to be neuroprotective in several models of brain injury, yet its influence on periventricular leukomalacia still remains elusive. Here we investigated whether repeated administration of EP could protect against white matter injury after hypoxia-ischemia (HI) (right common carotid artery ligation and 6 % O2 for 60 min) in post-natal 3 day rat pups. EP was injected (50 mg/kg, intraperitoneally) 10 min, 1 and 24 h after HI insult. Treatment with EP significantly reduced HI-induced ventricular enlargement, loss of developing oligodendrocytes, and hypomyelination. We further demonstrated a marked inhibitory effect of EP on inflammatory responses, as indicated by the decreased number of activated microglia and astrocytes and the reduced release of proinflammatory cytokines. Moreover, EP down-regulated the expression of cleaved caspase-3 and Bax, and up-regulated Bcl-2 expression after HI exposure. In conclusion, our results demonstrated that EP was able to provide potent protection on white matter injury through blocking the cerebral inflammatory responses and modulating the apoptotic death program of oligodendrocytes, indicating a potential neuroprotective agent in neonatal brain injury.
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Identification of isocitrate dehydrogenase 1 as a potential diagnostic and prognostic biomarker for non-small cell lung cancer by proteomic analysis.
Mol. Cell Proteomics
PUBLISHED: 11-07-2011
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Lung cancer is the leading cause of cancer-related death in the world. To explore tumor biomarkers for clinical application, two-dimensional fluorescence difference gel electrophoresis and subsequent MALDI-TOF/TOF mass spectrometry were performed to identify proteins differentially expressed in 12 pairs of lung squamous cell tumors and their corresponding normal tissues. A total of 28 nonredundant proteins were identified with significant alteration in lung tumors. The up-regulation of isocitrate dehydrogenase 1 (IDH1), superoxide dismutase 2, 14-3-3?, and receptor of activated protein kinase C1 and the down-regulation of peroxiredoxin 2 in tumors were validated by RT-PCR and Western blot analysis in independent 15 pairs of samples. Increased IDH1 expression was further verified by the immunohistochemical study in extended 73 squamous cell carcinoma and 64 adenocarcinoma clinical samples. A correlation between IDH1 expression and poor overall survival of non-small cell lung cancer (NSCLC) patients was observed. Furthermore, ELISA analysis showed that the plasma level of IDH1 was significantly elevated in NSCLC patients compared with benign lung disease patients and healthy individuals. In addition, knockdown of IDH1 by RNA interference suppressed the proliferation of NSCLC cell line and decreased the growth of xenograft tumors in vivo. These observations suggested that IDH1, as a protein promoting tumor growth, could be used as a plasma biomarker for diagnosis and a histochemical biomarker for prognosis prediction of NSCLC.
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The impact of positive cancer family history on the clinical features and outcome of patients with non-small cell lung cancer.
Fam. Cancer
PUBLISHED: 10-04-2011
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The purpose of this study is to investigate the impact of positive cancer/lung cancer family history (FH) on clinical features and outcome in non-small cell lung cancer (NSCLC) patients. We analyzed 4,491 NSCLC patients with NSCLC who presented from January 1999-December 2005. Chi-square test and Wilcoxon test were used for univariate comparisons, while Cox Proportional Hazards regression analysis was performed to evaluate the adjusted risk of death. Univariate probability of survival was calculated using Kaplan-Meier estimate and compared using the log-rank test. Of 4,491 patients, 579 patients (12.89%) had positive FH, including 233 patients (5.19%) with FH of lung cancer. Patients with positive lung cancer FH, compared to those with negative FH, were diagnosed at earlier age (57 vs. 60; P < 0.001), presented more cases of adenocarcinoma (58.80 vs. 50.69%; P = 0.016), and at more advanced stage (Stage IIIB/IV 45.74 vs. 36.79%; P < 0.001). These differences were also detected in patients with positive cancer FH. In addition, more females and non-smokers were among patients with positive cancer FH (30.05 vs. 26.15%; P = 0.045 and 39.90 vs. 33.82%; P = 0.008, respectively). Furthermore, patients with advanced cancer (stage IIIB/IV) who had positive FH had lower response rate to chemotherapy (CR&PR 24.68 vs. 34.42%; P = 0.024). Nevertheless, patients with positive lung cancer FH had better prognosis (P = 0.015), especially if diagnosed at an early stage (P = 0.035), and their adjusted relative risk of death was lower (RR 0.69; 95% CI: 0.51-0.93; P = 0.015). Definite epidemiologic and survival differences exist between NSCLC patients with positive or negative FH of cancer. Our results suggest that cancer FH is an important factor of clinical features, and could serve as a prognostic indicator for NSCLC.
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On the likelihood of SCN1A microdeletions or duplications in Dravet syndrome with missense mutation.
Brain Dev.
PUBLISHED: 08-27-2011
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This study examines whether microdeletions and duplications of the gene encoding ?1 subunit of the sodium channel (SCN1A) are underlying causes in Dravet syndrome (DS) with SCN1A missense mutation. Multiple exonic deletions were identified in 8/84 patients without mutation and 0/41 patients with missense mutations. Our findings indicate that while microdeletions are not rare in SCN1A-negative patients, they are not likely to be present simultaneously with other SCN1A mutations.
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Effects of linoleate on cell viability and lipid metabolic homeostasis in goose primary hepatocytes.
Comp. Biochem. Physiol., Part A Mol. Integr. Physiol.
PUBLISHED: 01-26-2011
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Studies have shown linoleate could not only promote cell viability but also affect lipid metabolism in mammals. However, to what degree these effects are mediated by steatosis in goose primary hepatocytes is unknown. In this study, the effect of linoleate on the lipid metabolic homeostasis pathway was determined. We measured the mRNA levels of genes involved in triglyceride synthesis, lipid deposition, ?-oxidation, and assembly and secretion of VLDL-TGs in goose (Anser cygnoides) primary hepatocytes. Linoleate significantly increased goose hepatocyte viability, and linoleate at 0.125 mM, 0.25 mM, 0.5 mM and 1.0 mM all showed a significant effect on TG accumulation. However, with increasing linoleate concentrations, the extracellular TG concentration and extracellular VLDL gradually decreased. DGAT1, DGAT2, PPAR?, PPAR?, FoxO1, MTP, PLIN and CPT-1 mRNA was detected by real-time PCR. With increasing linoleate concentrations, the changes in DGAT1, DGAT2, PPAR? and CPT-1 gene expression, which regulates hepatic TG synthesis and fatty acid oxidation, first increased and then decreased. Additionally, FoxO1 and MTP gene expression was reduced with increasing linoleate concentrations, and the change in PLIN gene expression was increased at all concentrations, similar to the regulation of intracellular TG accumulation. In conclusion, linoleate regulated TG accumulation and increased hepatocyte viability. The data suggest that linoleate does promote goose hepatocyte viability and steatosis, which may up-regulate TG synthesis-relevant gene expression, suppress assembly and secretion of VLDL-TGs, and increase fatty acid oxidation properly to function of goose primary hepatocytes.
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[Diagnostic value of ProGRP and NSE for small cell lung cancer: a meta-analysis].
Zhongguo Fei Ai Za Zhi
PUBLISHED: 12-17-2010
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pro-gastrin-releasing peptide (ProGRP) and neuron specific enolase (NSE) have become hotspot of tumor markers for small cell lung cancer (SCLC), and the aim of this study is to evaluate and compare the diagnostic value of serum ProGRP and NSE in SCLC by meta-analysis.
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Effect of HSPC016 gene expression on the aggregative growth of dermal papillae cells.
Australas. J. Dermatol.
PUBLISHED: 10-13-2010
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In previous studies, HSPC016 was identified as a differentially expressed gene in dermal papilla cells (DPC) with aggregative behaviour. To clarify its role in the regulation of DPC, the recombinant HSPC016 protein was expressed using the Pichia pastoris expression system, and three small interfering ribonucleic acid duplexes (siRNA) were designed and transfected into DPC. Results showed that DPC with the HSPC016 gene inhibited, exhibit non-aggregative behaviour and grow much slower than normal DPC, and that the recombinant HSPC016 protein could promote the proliferation of high-passage DPC and induce its aggregative behaviour.
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Screening and identification of differentially expressed genes in goose hepatocytes exposed to free fatty acid.
J. Cell. Biochem.
PUBLISHED: 09-28-2010
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The overaccumulation of triglycerides in hepatocytes induces hepatic steatosis; however, little is known about the mechanism of goose hepatic steatosis. The aim of this study was to define an experimental model of hepatocellular steatosis with TG overaccumulation and minimal cytotoxicity, using a mixture of various proportions of oleate and palmitate free fatty acids (FFAs) to induce fat-overloading, then using suppressive subtractive hybridization and a quantitative PCR approach to identify genes with higher or lower expression levels after the treatment of cells with FFA mixtures. Overall, 502 differentially expressed clones, representing 21 novel genes and 87 known genes, were detected by SSH. Based on functional clustering, up- and down-regulated genes were mostly related to carbohydrate and lipid metabolism, enzyme activity and signal transduction. The expression of 20 selected clones involved with carbohydrate and lipid metabolism pathways was further studied by quantitative PCR. The data indicated that six clones similar to the genes ChREBP, FoxO1, apoB, IHPK2, KIF1B, and FSP27, which participate in de novo synthesis of fatty acid and secretion of very low density lipoproteins, had significantly lower expression levels in the hepatocytes treated with FFA mixtures. Meanwhile, 13 clones similar to the genes DGAT-1, ACSL1, DHRS7, PPAR?, L-FABP, DGAT-2, PCK, ACSL3, CPT-1, A-FABP, PPAR?, MAT, and ALDOB had significantly higher expression levels in the hepatocytes treated with FFA mixtures. These results suggest that several metabolic pathways are altered in goose hepatocytes, which may be useful for further research into the molecular mechanism of goose hepatic steatosis.
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Effects of palmitic acid on lipid metabolism homeostasis and apoptosis in goose primary hepatocytes.
Mol. Cell. Biochem.
PUBLISHED: 07-24-2010
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Studies have shown that not only does palmitic acid promote triglyceride (TG) accumulation, but it also affects cell viability in in vitro steatosis models. However, to what degree these effects are mediated by steatosis in goose primary hepatocytes is unknown. In this study, the effects of palmitic acid on the lipid metabolism homeostasis pathway and on apoptosis were determined. The authors measured the mRNA levels of genes involved in TG synthesis, lipid deposition, fatty acid oxidation and the assembly and secretion of VLDL-TG in goose primary hepatocytes. The results indicated that palmitic acid can significantly reduce the activity of goose hepatocytes, and that palmitic acid had a significant effect on TG accumulation; however, with increasing palmitic acid concentrations, the extracellular TG and extracellular VLDL concentration gradually decreased. With increasing palmitic acid concentrations, the gene expression levels of DGAT1, DGAT2, PPAR?, CPT-1, FoxO1 and MTTP (which regulate hepatic TG synthesis, fatty acid oxidation and the assembly and secretion of VLDL-TGs) first increased and then decreased; the change in PLIN gene expression was palmitic acid dose-dependent, similar to the regulatory mode of intracellular TG accumulation. In conclusion, this study clearly shows that palmitic acid can promote TG accumulation and induce apoptosis in goose primary hepatocytes, and this effect may be related to the lipid metabolism pathway.
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Identification of differentially expressed genes between hepatocytes of Landes geese (Anser anser) and Sichuan White geese (Anser cygnoides).
Mol. Biol. Rep.
PUBLISHED: 03-05-2010
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In this study, we examined gene expression in order to identify genes that are differentially expressed between the hepatocytes of Sichuan White geese and Landes geese. We hypothesized that such genes may be involved in the different predispositions between these two species to develop hepatic steatosis. RNA was isolated from primary hepatocytes of the two species, and suppression subtractive hybridization was employed to screen for genes that showed differences in mRNA expression. We built and characterized two reciprocal cDNA libraries that were enriched in genes up-regulated in Landes geese or Sichuan White geese. Using dot blot analysis we identified 128 of 600 randomly selected sequences that demonstrated differential expression between the two species. Of these differentially expressed genes, 115 sequences shared high homology with 46 known genes and 13 sequences corresponded to eight novel expressed sequence tags (ESTs). Based on functional clustering, up and down-regulated genes were mostly related to lipid metabolism, nuclear mRNA splicing, enzyme activity and transcription control. The expression of 18 selected clones was further studied by quantitative PCR. The data showed that eight clones similar to the genes ACSL5, CTGF, CIDEA, PPAR?, PCK, GSTS1, RPS4X, and THBS1 had significantly higher expression levels in the hepatocytes of Landes geese. In contrast, seven clones similar to the genes ADH5, YBX1, ASAH1, UCB, AOPVLDL, SCD-1, and ELOVL-6 had significantly higher expression levels in the hepatocytes of Sichuan White geese.
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The role of LXR alpha in goose primary hepatocyte lipogenesis.
Mol. Cell. Biochem.
PUBLISHED: 08-06-2009
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In this study, we investigate the role of liver X receptor alpha (LXR alpha) in lipogenesis in geese in order to understand the differences in hepatic steatosis mechanisms between mammals and waterfowl. Primary goose hepatocytes were isolated and treated with the LXR alpha agonist T0901317. Triglyceride (TG) accumulation, acetyl-CoA carboxylase alpha (ACC alpha) and fatty acid synthase (FAS) activities, and gene expression levels of LXR alpha, sterol regulatory element-binding proteins-1 (SREBP-1), FAS, ACC alpha and lipoprotein lipase (LPL) were measured in primary hepatocytes. We found a dose-dependent up-regulation of TG accumulation, ACC, and FAS activities and the mRNA levels of LXR alpha, SREBP-1, FAS, ACC alpha, and LPL genes in the presence of To-901317. We also found that binding of nuclear SREBP-1 to ACC alpha SRE sequence was induced by To-901317 (P < 0.05). In conclusion, LXR alpha is involved in the induction of the lipogenic pathway through activation of SREBP-1 and its target genes in goose primary hepatocytes.
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Nanocrystalline hydroxyapatite with simultaneous enhancements in hardness and toughness.
Biomaterials
PUBLISHED: 07-15-2009
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Using a series of dense hydroxyapatite (HA) bodies with well controlled grain sizes ranging from sub-micrometers to nanometers, we show that simultaneous improvements in hardness and toughness can be attained for nanocrystalline (nc) HA. It is demonstrated that the hardness of HA follows the Hall-Petch relationship as the grain size decreases from sub-micrometers to nanometers. In the same grain size range, the toughness of HA increases by as much as 74% because of the enhanced crack deflection associated with a transition from transgranular to intergranular cracking, promoted by the reduced grain size in the nanoscale. The mechanisms for simultaneous enhancements in the hardness and toughness of nc HA are discussed. It is anticipated that the principle of simultaneous improvements in hardness and toughness discovered in this study is also applicable to other nc ceramics, particularly non-cubic ceramics, with anisotropic elastic and thermal expansion properties.
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The role of insulin and glucose in goose primary hepatocyte triglyceride accumulation.
J. Exp. Biol.
PUBLISHED: 05-05-2009
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In order to obtain some information on how fatty liver arises in geese, we investigated the role of insulin and glucose in triglyceride (TG) accumulation in goose primary hepatocytes. Goose primary hepatocytes were isolated and treated with insulin and glucose. Compared with the control group, 100 and 150 nmol l(-1) insulin increased TG accumulation, acetyl-CoA carboxylase-alpha (ACCalpha) and fatty acid synthase (FAS) activity, and the mRNA levels of sterol regulatory element-binding protein-1 (SREBP-1), FAS and ACCalpha genes. Insulin at 200 nmol l(-1) had an inhibiting effect on TG accumulation and the activity of ACC and FAS, but increased the gene expression of SREBP-1, FAS and ACCalpha. We also found that high glucose (30 mmol l(-1)) increased the TG level, ACC and FAS activity, and the mRNA levels of SREBP-1 and FAS. However, there was no effect of high glucose on ACCalpha mRNA level. In addition, the interaction between insulin and glucose was observed to induce TG accumulation, ACC and FAS activity, and gene expression of SREBP-1, FAS and ACCalpha, and increase SREBP-1 nuclear protein level and binding of nuclear SREBP-1 and the SRE response element of the ACC gene. The result also indicated that the glucose-induced TG accumulation decreased after 96 h when the hepatocytes were cultured with 30 mmol l(-1) glucose. In conclusion, insulin and glucose may affect hepatic lipogenesis by regulating lipogenic gene expression and lipogenic enzyme activity in goose hepatocytes, and SREBP-1 might play an important role in the synergetic activation of lipogenic genes. We propose that the utilization of accumulated TG in hepatocytes is the reason for the reversible phenomenon in goose hepatocellular steatosis.
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Synthesis of high purity hydroxyapatite nanopowder via sol-gel combustion process.
J Mater Sci Mater Med
PUBLISHED: 01-10-2009
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A polymeric sol-gel combustion method has been used to synthesize nanocrystalline hydroxyapatite (HA) powder from calcium nitrate and triethyl phosphate with the addition of NH(4)OH. The sol-gel combustion process generates phase-pure nanocrystalline HA powder, as characterized using Fourier transform infrared (FTIR), X-ray diffraction (XRD), and transmission electron microscopy (TEM). Sintering of the HA powder compact at 1200 degrees C for 2 h leads to a 93% theoretical dense ceramic body. This method offers an easy route for the preparation of phase-pure nanocrystalline HA powder.
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Ethyl pyruvate protects against lipopolysaccharide-induced white matter injury in the developing rat brain.
Int. J. Dev. Neurosci.
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The neuroprotective effects of ethyl pyruvate (EP) have been proved in several brain injury models, yet very little is known about its action on neonatal white matter injury. To investigate the effect of EP on white matte damage, a stereotactic intracerebral injection of lipopolysaccharide (LPS, 1mg/kg) was performed on postnatal day 5 Sprague-Dawley rat pups, and EP was administrated intraperitoneally at a dose of 40mg/kg immediately, 1h and 12h after LPS exposure. Significantly, treatment with EP reduced LPS-induced ventricle dilation, loss of O4+ and O1+ oligodendrocytes, apoptosis of oligodendrocytes, and hypomyelination. The protective effect of EP was associated with suppressed inflammatory responses, indicated by the inhibition of activation of microglia and astrocytes, as well as the decreased expression of tumor necrosis factor-alpha (TNF-?) and interleukin-1beta (IL-1?) in rat brains. Also, EP prevented the elevation of cleaved caspase-3 in periventricular white matter tissue after LPS insult. Taken together, these results suggest that EP confers potent protection against LPS-induced white matter injury via its anti-inflammatory and anti-apoptotic properties.
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Analysis of the tumor length and other prognosis factors in pT1-2 node-negative esophageal squamous cell carcinoma in a Chinese population.
World J Surg Oncol
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Tumor length is an important prognostic factor for many carcinomas, but its role in esophageal cancer remained undetermined. The aim of this study was to investigate the effect of tumor length on survival for patients with confined tumors (grade pT1-2) without lymph-node metastases in esophageal squamous cell carcinoma.
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The cloning, characterization, and expression profiling of the LRP8 gene in duck (Anas platyrhynchos).
Mol. Cell. Biochem.
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Low-density lipoprotein receptor-related protein 8 (LRP8) is a member of the low-density lipoprotein receptor gene family that functions in body lipoprotein homeostasis. In this study, reverse transcription-polymerase chain reaction, rapid amplification of cDNA ends, and real-time PCR were performed to characterize the duck LRP8 gene. The cDNA of duck LRP8 contained a 14-bp 5 UTR, a 2754-bp open reading frame, and a 189-bp 3 UTR. The duck LRP8 encoded a protein of 917 amino acid residues composed of five functional domains and resembling other members of the LDLR family, and it displayed high nucleotide and amino acid homology to the LRP8 sequences in other avian species. The mRNA expression level of LRP8 was greater in duck extra-hepatic adipose tissue than in the liver. The peak expression values of LRP8 in both liver and adipose tissues occurred at week 1 and were significantly higher than the values observed during any other week (p < 0.05). Differences in the expression patterns of LRP8 mRNA from weeks 2 to 8 of growth were observed in different organs. A consistent low expression was observed in the liver, and fluctuating expression was observed in the subcutaneous adipose tissue (up- and then down-regulated) and abdominal adipose tissue (down-, then up-, then down-regulated). These findings suggest that LRP8 might play more important roles in regulating lipid metabolism in extra-hepatic adipose tissues than in the liver during early growth after hatching in the duck.
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Epileptic seizure detection with linear and nonlinear features.
Epilepsy Behav
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Automatic seizure detection is significant in both diagnosis of epilepsy and relieving the heavy workload of inspecting prolonged EEG. This paper presents a new seizure detection method for multi-channel long-term EEG. The fractal intercept derived from fractal geometry is extracted as a novel nonlinear feature of EEG signals, and the relative fluctuation index is calculated as a linear feature. The feature vector, consisting of the two EEG descriptors, is fed into a single-layer neural network for classification. Extreme learning machine (ELM) algorithm is adopted to train the neural network. Finally, post-processing including smoothing, channel fusion, and collar technique is employed to obtain more accurate and stable results. Both the segment-based and event-based assessments are used for the performance evaluation of this method on the 21-patient Freiburg dataset. The segment-based sensitivity of 91.72% and specificity of 94.89% were achieved. For the event-based assessment, this method yielded a sensitivity of 93.85% with a false detection rate of 0.35/h.
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De novo lipogenesis in the liver and adipose tissues of ducks during early growth stages after hatching.
Comp. Biochem. Physiol. B, Biochem. Mol. Biol.
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In vivo de novo lipogenesis (DNL) in the liver and adipose tissues of ducks during early developmental stages after hatching has not previously been investigated. In this study, female Peking ducks (Anas platyrhynchos) at weeks 1 to 8 post-hatching were selected for experimentation. We measured the mRNA levels of 6 DNL-related genes in the duck liver, subcutaneous adipose tissue and abdominal adipose tissue by real-time PCR during the 8 weeks. Correlations of the plasma triacylglycerol (TG) and very low density lipoprotein (VLDL) concentrations with fat deposition at these sites were also detected during growth. Our results showed that fat content was highest in the subcutaneous adipose tissue and lowest in the liver during the growth period we studied. Additionally, plasma VLDL and TG were significantly associated with lipid content in adipose tissue (P<0.05), but not in the liver. Lastly, in the growing birds, the expression levels of lipogenic genes (with the exceptions SREBP-1c and SCD1) were much higher in the liver than in the adipose tissues, and the maximal expression levels of these genes occurred at week 4 or 5 at these sites. These findings indicated that the main site of DNL is always the liver in post-hatching ducks, and adipose tissues are of little importance for DNL. Taken together, our results suggested that the plasma lipoproteins contribute greatly to fat deposition in adipose tissues originating from hepatic lipogenesis.
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Molecular cloning and in silico analysis of the duck (Anas platyrhynchos) MEF2A gene cDNA and its expression profile in muscle tissues during fetal development.
Genet. Mol. Biol.
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The role of myogenic enhancer transcription factor 2a (MEF2A) in avian muscle during fetal development is unknown. In this work, we cloned the duck MEF2A cDNA sequence (GenBank accession no. HM460752) and examined its developmental expression profiles in cardiac muscle, non-vascular smooth muscle and skeletal muscle. Duck MEF2A cDNA comprised 1479 bp encoding 492 amino acid residues. In silico analysis showed that MEF2A contained MADS (MCM1, AGAMOUS, DEFICIENS and SRF - serum response factor), MEF2 and mitogen-activated protein kinase (MAPK) transcription domains with high homology to related proteins in other species. Modified sites in these domains were conserved among species and several variants were found. Quantitative PCR showed that MEF2A was expressed in all three muscles at each developmental stage examined, with the expression in smooth muscle being higher than in the other muscles. These results indicate that the conserved domains of duck MEF2A, including the MADS and MEF2 domains, are important for MEF2A transcription factor function. The expression of MEF2A in duck smooth muscle and cardiac muscle suggests that MEF2A plays a role in these two tissues.
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MicroRNA-25 promotes cell migration and invasion in esophageal squamous cell carcinoma.
Biochem. Biophys. Res. Commun.
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MicroRNAs (miRNAs) as a species of small non coding single stranded RNA of about 21-25 nucleotides have important roles in the development of different cancers. In present study, we found that the expression of miR-25 was up-regulated in 60 esophageal squamous cell carcinoma (ESCC) tissues compared with matched adjacent non-cancer tissues. Moreover, we demonstrated that the up-regulation of miR-25 was significantly correlated with the status of lymph node metastasis and TNM (Tumor, Node and Metastasis) stage. Furthermore, over-expression of miR-25 markedly promoted migration and invasion of ESCC cells. On the contrary, down-regulation of miR-25 inhibited the migration and invasion of cells. E-cadherin(CDH1) is a very important tumor metastasis suppressor. We further identified that miR-25 directly targeted CDH1 3-untranslated region (3UTR) and repressed the expression of CDH1. These results, for the first time, demonstrate that miR-25 promotes ESCC cell migration and invasion by suppressing CDH1 expression.
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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.