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Find video protocols related to scientific articles indexed in Pubmed.
Nemo-like kinase (NLK) inhibits the progression of NSCLC via negatively modulating WNT signaling pathway.
J. Cell. Biochem.
PUBLISHED: 09-03-2014
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Nemo-like kinase (NLK), an evolutionarily conserved serine/threonine kinase, is a critical regulator of various cancers. NLK expression was evaluated by Western blot in 8 paired fresh non-small-cell lung cancer (NSCLC) tissues and immunohistochemistry (IHC) on 83 paraffin-embedded slices. NLK was lowly expressed in NSCLC and significantly associated with NSCLC histological differentiation, clinical stage, lymph node status, and Ki-67. Multivariate analysis indicated that low NLK expression was an independent prognostic factor for NSCLC patients' low survival rate. In vitro, after the release of NSCLC cell line A549 from serum starvation, the expression of NLK was downregulated, whereas the cell-cycle-related proteins were upregulated. In addition, we used RNA interference to knock down NLK expression, then observed its effects on NSCLC's growth in vitro. Western blot analyses indicated that deletion of NLK was positively correlated with cell-cycle-related proteins. The present investigation demonstrated that suppression of NLK expression resulted in significant promotion of proliferation in NSCLC cells. And flow cytometry further indicated that loss of NLK promoted cell proliferation by facilitating S-phase and mitotic entry. Besides, the transcription activity of ?-catenin/TCF in A549 cells was remarkably enhanced when NLK was knocked down, which suggested that NLK participated in NSCLC cell proliferation via medulating Wnt signaling pathway. Based on these findings, we can provide a potential strategy for NSCLC therapy.
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One-Step Modification of Fabrics with Bioinspired Polydopamine@Octadecylamine Nanocapsules for Robust and Healable Self-Cleaning Performance.
Small
PUBLISHED: 08-09-2014
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An in-situ polymerization to coat fabrics with polydopamine-encapsulated octadecylamine endows the fabrics with self-cleaning and self-healing abilities. The treated fabric exhibits self-healing after losing its hydrophobicity. It is durable against washing and mechanical abrasion without changing the hydrophobicity. Thanks to the versatile adhesive property of polydopamine, the approach is compatibile with a variety of substrates, such as fabrics, glass, sponge, paper, and polymeric materials.
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Identification of Gem as a new candidate prognostic marker in hepatocellular carcinoma.
Pathol. Res. Pract.
PUBLISHED: 07-17-2014
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GTP binding protein overexpressed in skeletal muscle (Gem) is a Ras-related protein whose expression is induced in several cell types upon activation by extracellular stimuli. To investigate the potential roles of Gem in hepatocellular carcinoma (HCC), expression of Gem was examined in human HCC samples. Western blot analysis showed that compared with primary human hepatocytes and adjacent noncancerous tissue, significant down-regulation of Gem was found in HCC cells and tumor tissues. In addition, immunohistochemical analysis of Gem expression was investigated in 108 specimens of HCC tissues. Clinicopathological data were collected to analyze the association with Gem expression. Expression of Gem was significantly negatively correlated with histological grade (P=0.001), tumor size (P=0.020), and vascular invasion (P=0.005), and Gem was also negatively correlated with proliferation marker Ki-67 (P<0.01). More importantly, the Kaplan-Meier survival curves analysis revealed that low expression of Gem was associated with poor prognosis in HCC patients. Univariate analysis showed that Gem expression was associated with poor prognosis (P=0.006). Multivariate analysis indicated that Gem expression was an independent prognostic marker for HCC (P=0.007). Finally, serum starvation and release experiments showed that Gem expression was negatively related with cell proliferation. In the conclusion, our results suggested that down regulation of Gem expression was involved in the pathogenesis of hepatocellular carcinoma, and it might be a favorable independent prognostic parameter for HCC.
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The transcriptional regulation of SOX2 on FOXA1 gene and its application in diagnosis of human breast and lung cancers.
Clin. Lab.
PUBLISHED: 07-15-2014
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Recent study demonstrated the important contribution of SOX2 to tumorigenesis and metastasis properties of various types of cancers and strongly supported the concept that SOX2 can be used as an effective marker for diagnosis and predicting prognosis of cancer patients. However, our previous RNA-Seq results from human lung cancer cell line A549 showed that some oncogenes, including FOXA1 are negatively regulated by SOX2.
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Identification and characterization of a type-2 diacylglycerol acyltransferase (DGAT2) from Rhodosporidium diobovatum.
Antonie Van Leeuwenhoek
PUBLISHED: 07-07-2014
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Triacylglycerols (TAGs), synthesized in the microsomal membranes of eukaryotes, serve as a primary storage form of carbon and energy in microorganisms. For this reason, TAGs produced by organisms have great potential to become biofuels and facilitate researchers to look for alternative renewable sources of energy. The present study describes the identification and functional characterization of a type-2 diacylglycerol acyltransferase from Rhodosporidium diobovatum, designated as RdDGAT, which catalyzed the final step of TAG synthesis. A full-length cDNA clone for RdDGAT was obtained, and its biological activity was proven by being expressed in a Saccharomyces cerevisiae quadruple mutant that was defective in TAG synthesis. Enzymatic assays were performed and finally the existence of TAGs in the transformed Saccharomyces cerevisiae quadruple mutant was determined using the method of thin-layer chromatography. Substrate preference experiments revealed that RdDGAT preferred unsaturated fatty acids over saturated ones. Through further analysis, we assume that the evolution and expression characteristics of the RdDGAT gene perhaps is the result of adaption to its oligotrophic and cold living environment.
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Mucosal-associated invariant T-cell function is modulated by programmed death-1 signaling in patients with active tuberculosis.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 07-01-2014
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Mucosal-associated invariant T (MAIT) cells have been proven to play an important role in host defense against mycobacterial infection in animal infection models; however, the functional role of MAIT cells in patients with active tuberculosis (TB) is still largely unknown.
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[Methylation of ER and ER gene and its significance in primary and relapsed/metastatic lesions of breast cancer].
Zhonghua Zhong Liu Za Zhi
PUBLISHED: 05-07-2014
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To investigate the different expressions of ER and ER gene status between primary and relapsed/metastatic lesions and their clinical significance.
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Decreasing the amount of trypsin in in-gel digestion leads to diminished chemical noise and improved protein identifications.
J Proteomics
PUBLISHED: 05-02-2014
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Pre-fractionation by gel electrophoresis is often combined with liquid chromatography-mass spectrometry (LC-MS) for large-scale profiling of complex protein samples. An essential component of this widely applied proteomic platform is in-gel protein digestion. In nearly two decades of practicing this approach, an extremely high level of trypsin has been utilized due to the consideration of slow enzyme diffusion into the gel matrix. Here we report that trypsin autolysis products contribute to the bulk of chemical noise in in-gel digestion and remarkably we found evidence that the amount of trypsin can be slashed by an order of magnitude with comparable digestion performance. By revising perhaps the most critical element of this decade-old digestion protocol, the proteomics community relying on gel separation prior to LC-MS analysis will benefit instantly from much lowered cost due to enzyme expenditure. More importantly, substantially reduced chemical noise (i.e., trypsin self-cleavage products) as a result of less enzyme usage translates into more protein identifications when limited amounts of samples are the interest of interrogation.
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Legumain protease-activated TAT-liposome cargo for targeting tumours and their microenvironment.
Nat Commun
PUBLISHED: 04-23-2014
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Specific targeting and cellular internalization are key properties for carriers of antitumor therapeutic agents. Here, we develop a drug carrier through the attachment of substrate of endoprotease legumain, alanine-alanine-asparagine (AAN), to cell-penetrating peptides (TAT, trans-activating factor). The addition of the AAN moiety to the fourth lysine in the TAT creates a branched peptide moiety, which leads to a decrease in the transmembrane transport capacity of TAT by 72.65%. Legumain efficiently catalyses the release of TAT-liposome from the AAN-TAT-liposome and thereby recovers the penetrating capacity of TAT. Doxorubicin carried by the AAN-TAT-liposome led to an increase in the tumoricidal effect of doxorubicin and a reduction in its systemic adverse effects in comparison with doxorubicin carried by a control delivery system. Thus, the specific targeting and high efficiency of this delivery platform offers a novel approach to limit the toxicity of anticancer agents as well as increasing their efficacy in cancer therapy.
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Increased frequency of ILT2-expressing CD56(dim)CD16(+) NK cells correlates with disease severity of pulmonary tuberculosis.
Tuberculosis (Edinb)
PUBLISHED: 03-30-2014
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The functional role of ILT2 in anti-tuberculosis immunity remains to be elucidated. In this study, we investigated expression and functions of ILT2 on NK cells during TB infection. The frequency of CD56(dim)CD16(+) NK cells that expressed ILT2 was significantly elevated in patients with active pulmonary TB as compared with tuberculin-positive healthy controls (p < 0.0001). TB patients with Mycobacterium tuberculosis smear/culture-positive result had significantly higher frequency of ILT2-expressing CD56(dim)CD16(+) NK cells than those with M. tuberculosis smear/culture-negative result (p < 0.0001), suggesting that ILT2 expression on CD56(dim)CD16(+) NK cells correlated with disease severity of pulmonary TB. ILT2-expressing CD56(dim) NK cells had a functional defect, as evidenced by reduced expression of CD107a and IFN-?. Spontaneous apoptosis in ILT2(+)CD56(dim) NK cells was higher than in ILT2(-) cells. Blocking of ILT2 signaling resulted in increased expression of CD107a on CD56(dim)CD16(+) NK cells. It is concluded that ILT2 has an inhibitory role on NK cells in patients with active TB.
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An iron-containing dodecameric heptosyltransferase family modifies bacterial autotransporters in pathogenesis.
Cell Host Microbe
PUBLISHED: 03-20-2014
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Autotransporters deliver virulence factors to the bacterial surface by translocating an effector passenger domain through a membrane-anchored barrel structure. Although passenger domains are diverse, those found in enteric bacteria autotransporters, including AIDA-I in diffusely adhering Escherichia coli (DAEC) and TibA in enterotoxigenic E. coli, are commonly glycosylated. We show that AIDA-I is heptosylated within the bacterial cytoplasm by autotransporter adhesin heptosyltransferase (AAH) and its paralogue AAH2. AIDA-I heptosylation determines DAEC adhesion to host cells. AAH/AAH2 define a bacterial autotransporter heptosyltransferase (BAHT) family that contains ferric ion and adopts a dodecamer assembly. Structural analyses of the heptosylated TibA passenger domain reveal 35 heptose conjugates forming patterned and solenoid-like arrays on the surface of a ? helix. Additionally, CARC, the AIDA-like autotransporter from Citrobacter rodentium, is essential for colonization in mice and requires heptosylation by its cognate BAHT. Our study establishes a bacterial glycosylation system that regulates virulence and is essential for pathogenesis.
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Systematic review focusing on the excretion and protection roles of sweat in the skin.
Dermatology (Basel)
PUBLISHED: 02-22-2014
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The skin excretes substances primarily through sweat glands. Several conditions have been demonstrated to be associated with diminished sweating. However, few studies have concentrated on the metabolism and excretion of sweat. This review focuses on the relationship between temperature and the thermoregulatory efficacy of sweat, and then discusses the excretion of sweat, which includes the metabolism of water, minerals, proteins, vitamins as well as toxic substances. The potential role of sweat secretion in hormone homeostasis and the effects on the defense system of the skin are also clarified.
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Analysis of the effect of repeated-pulse transcranial magnetic stimulation at the Guangming point on electroencephalograms.
Neural Regen Res
PUBLISHED: 01-19-2014
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Here, we administered repeated-pulse transcranial magnetic stimulation to healthy people at the left Guangming (GB37) and a mock point, and calculated the sample entropy of electroencephalo-gram signals using nonlinear dynamics. Additionally, we compared electroencephalogram sample entropy of signals in response to visual stimulation before, during, and after repeated-pulse tran-scranial magnetic stimulation at the Guangming. Results showed that electroencephalogram sample entropy at left (F3) and right (FP2) frontal electrodes were significantly different depending on where the magnetic stimulation was administered. Additionally, compared with the mock point, electroencephalogram sample entropy was higher after stimulating the Guangming point. When visual stimulation at Guangming was given before repeated-pulse transcranial magnetic stimula-tion, significant differences in sample entropy were found at five electrodes (C3, Cz, C4, P3, T8) in parietal cortex, the central gyrus, and the right temporal region compared with when it was given after repeated-pulse transcranial magnetic stimulation, indicating that repeated-pulse transcranial magnetic stimulation at Guangming can affect visual function. Analysis of electroencephalogram revealed that when visual stimulation preceded repeated pulse transcranial magnetic stimulation, sample entropy values were higher at the C3, C4, and P3 electrodes and lower at the Cz and T8 electrodes than visual stimulation followed preceded repeated pulse transcranial magnetic stimula-tion. The findings indicate that repeated-pulse transcranial magnetic stimulation at the Guangming evokes different patterns of electroencephalogram signals than repeated-pulse transcranial mag-netic stimulation at other nearby points on the body surface, and that repeated-pulse transcranial magnetic stimulation at the Guangming is associated with changes in the complexity of visually evoked electroencephalogram signals in parietal regions, central gyrus, and temporal regions.
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Folate and CD44 receptors dual-targeting hydrophobized hyaluronic acid paclitaxel-loaded polymeric micelles for overcoming multidrug resistance and improving tumor distribution.
J Pharm Sci
PUBLISHED: 01-17-2014
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The drug efflux mediated by P-glycoprotein (P-gp) transporter is one of the important factors responsible for multidrug resistance (MDR), and then the efficient intracellular drug delivery is an important strategy to overcome MDR of tumor cells. We describe and compare CD44 receptor single-targeting and folate (FA), CD44 receptors dual-targeting hyaluronic acid-octadecyl (HA-C18 ) micellar formulations to overcome MDR of tumor cells and to improve tumor distribution. In comparison with Taxol solution, the cytotoxicity of paclitaxel (PTX) loaded in HA-C18 and FA-HA-C18 micelles against drug-resistant tumor cells was improved significantly because of the increased intracellular delivery by active receptor-mediated endocytosis. Compared with the single-targeting micelles, dual-targeting micelles possessed better MDR-overcoming performance. Pharmacokinetic study demonstrated HA-C18 and FA-HA-C18 PTX-loaded micelles possessed much longer circulation and moderately larger AUC than Taxol solution. Above all, the tumor distribution in MCF-7 tumor-bearing mice of PTX encapsulated in HA-C18 and FA-HA-C18 micelles were 2.8 and 4.0 times higher than that of Taxol solution. It was concluded that dual-targeting FA-HA-C18 micelles demonstrate excellent MDR-overcoming ability and improved tumor distribution, and provide a novel effective nanoplatform for anticancer drug delivery in cancer chemotherapy.
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Ammonia gas sensors based on chemically reduced graphene oxide sheets self-assembled on Au electrodes.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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We present a useful ammonia gas sensor based on chemically reduced graphene oxide (rGO) sheets by self-assembly technique to create conductive networks between parallel Au electrodes. Negative graphene oxide (GO) sheets with large sizes (>10 ?m) can be easily electrostatically attracted onto positive Au electrodes modified with cysteamine hydrochloride in aqueous solution. The assembled GO sheets on Au electrodes can be directly reduced into rGO sheets by hydrazine or pyrrole vapor and consequently provide the sensing devices based on self-assembled rGO sheets. Preliminary results, which have been presented on the detection of ammonia (NH3) gas using this facile and scalable fabrication method for practical devices, suggest that pyrrole-vapor-reduced rGO exhibits much better (more than 2.7 times with the concentration of NH3 at 50 ppm) response to NH3 than that of rGO reduced from hydrazine vapor. Furthermore, this novel gas sensor based on rGO reduced from pyrrole shows excellent responsive repeatability to NH3. Overall, the facile electrostatic self-assembly technique in aqueous solution facilitates device fabrication, the resultant self-assembled rGO-based sensing devices, with miniature, low-cost portable characteristics and outstanding sensing performances, which can ensure potential application in gas sensing fields.
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Mismatch negativity of sad syllables is absent in patients with major depressive disorder.
PLoS ONE
PUBLISHED: 01-01-2014
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Major depressive disorder (MDD) is an important and highly prevalent mental disorder characterized by anhedonia and a lack of interest in everyday activities. Additionally, patients with MDD appear to have deficits in various cognitive abilities. Although a number of studies investigating the central auditory processing of low-level sound features in patients with MDD have demonstrated that this population exhibits impairments in automatic processing, the influence of emotional voice processing has yet to be addressed. To explore the automatic processing of emotional prosodies in patients with MDD, we analyzed the ability to detect automatic changes using event-related potentials (ERPs).
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SOX2 regulates apoptosis through MAP4K4-Survivin signaling pathway in human lung cancer cells.
Carcinogenesis
PUBLISHED: 11-14-2013
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Previous studies have implicated cancer stem cells in tumor recurrence and revealed that the stem cell gene SOX2 plays an important role in the tumor cell resistance to apoptosis. Nonetheless, the mechanism by which SOX2 regulates apoptosis signals remained undefined. Here, we demonstrated the surprising finding that silencing of the SOX2 gene effectively induces apoptosis via the activation of death receptor and mitochondrial signaling pathways in human non-small cell lung cancer cells. Unexpectedly, reverse transcription-PCR analysis suggested that downregulation of SOX2 leads to activation of MAP4K4, previously implicated in cell survival. Evaluation of the apoptotic pathways revealed an increased expression of key inducers of apoptosis, including tumor necrosis factor-? and p53, with concurrent attenuation of Survivin. Although p53 appeared dispensable for this pathway, the loss of Survivin in SOX2-deficient cells appeared critical for the observed MAP4K4 induced cell death. Rescue experiments revealed that SOX2-silencing-mediated killing was blocked by ectopic expression of Survivin, or by reduction of MAP4K4 expression. Clinically, expressions of Survivin and SOX2 were highly correlated with each other. The results reveal a key target of SOX2 expression and highlight the unexpected context-dependent role for MAP4K4, a pluripotent activator of several mitogen-activated protein kinase pathways, in regulating tumor cell survival.
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Targeted delivery of the RGD-labeled biodegradable polymersomes loaded with the hydrophilic drug oxymatrine on cultured hepatic stellate cells and liver fibrosis in rats.
Eur J Pharm Sci
PUBLISHED: 07-14-2013
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Oxymatrine (OM) is an alkaloid extracted from a Chinese herb that has been found to possess an anti-hepatic fibrosis effect, although its anti-fibrotic potential is limited due to a lack of targeting specificity, a short half-life and adverse effects. Polymersomes (PM) assembled from amphiphilic block copolymers represent promising vesicles for applications that include drug delivery and surface functionalization. The aim of this study was to develop a novel drug carrier based on PM modified with the peptide RGD and evaluate its therapeutic effect on liver fibrosis. A series of PM based on poly(ethylene glycol)-b-poly(?-caprolactone) (PEG-b-PCL) were prepared and characterized. OM was loaded into PM by a pH-gradient method then the OM-loaded PM was modified with RGD peptide to obtain RGD-PM-OM. The average drug loading of RGD-PM-OM, with a size of 95nm, was 6.8%. The targeting effects of the system were determined in cultured hepatic stellate cells (HSCs) and bile duct-ligated rats (BLD). RGD-PM-OM displayed better suppression of HSCs proliferation and significantly reduced the expression of the genes for ?-SMA and collagen l?1 in cultured HSCs. Furthermore, RGD-PM-OM exhibited markedly superior anti-fibrosis activity by reducing the levels of PC-III and IV-C in serum and connective tissue deposition in BLD compared with PM-OM and OM. These results indicate that targeted RGD-PM-OM markedly attenuates the effects of hepatic fibrosis.
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Determination of paclitaxel in hyaluronic acid polymeric micelles in rat blood by protein precipitation-micelle breaking method: application to a pharmacokinetic study.
J. Chromatogr. B Analyt. Technol. Biomed. Life Sci.
PUBLISHED: 07-02-2013
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An efficient dissociation of paclitaxel (PTX) from the home-made hyaluronic acid-octadecyl (HA-C18) polymeric micelles formulation in rat blood could not be achieved using previously published PTX analytical methods. So, we intended to develop the micelle-breaking method to determine paclitaxel encapsulated in the HA-C18 polymeric micelles in blood. The pretreatment method of blood samples adopted a simple one-step protein precipitation-micelle breaking process with methanol as micelle-breaking and protein precipitant solvents for complete extraction of PTX from HA-C18 micelles in blood. The micelle breaking efficiency of methanol was as high as 97.7%. Separation was carried out by gradient elution on an Acquity UPLC BEH C18 column with a mobile phase consisting of water (containing 0.1% formic acid) and acetonitrile. A total single run time was as short as 3.0min. Detection was performed by triple-quadrupole mass spectrometry with positive electrospray ionization as source ionization in multiple-reaction monitoring mode at m/z 854.3?286.2 for PTX and m/z 808.5?527.3 for the internal standard, docetaxel. The method demonstrated good linearity at the concentrations ranging from 20 to 10,000ng/mL. The intra- and inter-day relative standard deviations were less than 9.9%. The mean extraction recoveries of PTX and IS were 94.7% and 87.5%, respectively. In summary, the methanol protein precipitation-micelle breaking method could extract PTX completely from the polymeric micelles. Finally, the method was successfully applied to a pharmacokinetic study of the home-made PTX-loaded HA-C18 polymeric micelles and Taxol solution after intravenous administration in rats.
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Upregulated expression of CAP1 is associated with tumor migration and metastasis in hepatocellular carcinoma.
Pathol. Res. Pract.
PUBLISHED: 06-19-2013
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Hepatocellular carcinoma (HCC) is one of the most common cancers that exhibits high incidences of intrahepatic metastasis and tumor recurrence. Adenylate cyclase-associated protein 1 (CAP1), a protein involved in the regulation of actin filaments, was recently reported to play a role in cell motility and the pathology of pancreatic cancer. In this study, we examined a potential role of CAP1 in HCC progression, and found that CAP1 was overexpressed in HCC specimens compared with adjacent noncancerous liver tissues by Western blot analysis and real-time PCR assay. Further, immunohistochemical analysis in 107 HCC specimens revealed that overexpression of CAP1 was closely correlated only with tumor metastasis, but not with other clinicopathologic parameters. Univariate and multivariate survival analyses showed that CAP1 could be an independent prognostic factor for patients survival. In addition, immunofluorescent assay demonstrated that CAP1 was colocalized with actin in the leading edge of lamellipodium in HCC cells. Importantly, knocking-down the expression of CAP1 using small interfering RNA (siRNA) targeting CAP1 led to impaired migration of HCC cells. Collectively, our results indicated that upregulated expression of CAP1 might contribute heavily to the metastasis of HCC.
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Decomposition of NO in automobile exhaust by plasma-photocatalysis synergy.
Environ Sci Pollut Res Int
PUBLISHED: 05-30-2013
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The combination of plasma discharge and TiO2 photocatalysis exhibits high performances in the removal of nitrogen monoxide (NO). This article is aimed at elucidating the relationships between NO decomposition efficiency and various experimental parameters, including voltages, humidity and temperature. The experimental results indicate that the efficiency of NO removal by synergic plasma-catalyst coupling is significantly higher than plasma only or photocatalyst only systems. Moreover, the NO removal efficiency improves with the increase of applied voltage. Meanwhile, a higher humidity results in a reduced number of electron-hole pairs at the surface of TiO2 photocatalyst, leading to lower synergic purification efficiencies. Finally, the efficiency of NO removal is raised with the increase of temperature due to the fact that the adsorption of NO and water by nano-TiO2 is affected by environmental temperature.
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Decreased expression of SERPINB1 correlates with tumor invasion and poor prognosis in hepatocellular carcinoma.
J. Mol. Histol.
PUBLISHED: 05-29-2013
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SERPINB1 (serine protease inhibitor, clade B, member1) is a member of the SERPINB family. Recent studies suggested that SERPINB1 may suppress the migration and invasion of lung and breast cancers. In this study, we investigated a possible involvement of SERPINB1 in the regulation of hepatocellular carcinoma metastasis (HCC). The expression of SERPINB1 was evaluated using western blot analysis in 8 paired fresh HCC specimens and immunohistochemistrical assay on 67 paraffin-embedded HCC slices. SERPINB1 was downregulated in HCC specimens and correlatively related with two clinicopathologic features of HCC, metastasis (P = 0.000) and vein invasion (P = 0.006). Univariate and multivariate survival analyses showed a lower level of SERPINB1 expression is associated with poor prognosis and clinical outcome (P = 0.001). In addition, small interfering RNA targeting SERPINB1 was used to knock down the expression of SERPINB1 in Huh7 and BEL-7404 cells. We showed that interference of SERPINB1 promoted migration and invasion of HCC cells, while cell proliferation was not affected. Finally, we observed an apparent increase in the level of active matrix metalloproteinase-2 (MMP2) after SERPINB1 knockdown, implying that SERPINB1 might participate in the regulation of HCC metastasis through modulating the activation of matrix metalloproteinases. Overall, our results suggested an inhibitory role of SERPINB1 in the migration and invasion of HCC, implying that SERPINB1 might be a potential prognostic indicator of HCC metastasis.
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[Study on association between ERCC2/XPD single nucleotide polymorphisms and DNA adducts damage induced by B[a]P in vitro].
Wei Sheng Yan Jiu
PUBLISHED: 04-20-2013
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To evaluate the association between DNA damage repair capacity induced by environment carcinogen benzo[a] pyrene (B [a] P) and ERCC2/XPD single nucleotide polymorphisms(SNP).
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Vacuolar protein sorting 4B, an ATPase protein positively regulates the progression of NSCLC via promoting cell division.
Mol. Cell. Biochem.
PUBLISHED: 04-17-2013
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Vacuolar protein sorting 4B (VPS4B), a member of ATPase family proteins, plays a crucial role in lysosome-dependent degradation. Recently, it was found that VPS4B could negatively regulate breast cancer progression through promoting lysosomal-dependent degradation for EGFR. Nevertheless, other studies found that VPS4B was also essential for cell division and mitosis through insuring the maintenance of centrosome and spindle assembly. Thus, the role of VPS4B in cancer biology remains under debate. In this study, we analyzed the clinical significance of VPS4B in NSCLC. The expression of VPS4B was evaluated by Western blot in 8 paired fresh NSCLC tissues and immunohistochemistry on 105 paraffin-embedded slices. VPS4B was highly expressed in NSCLC and significantly associated with NSCLCs tumor size, histological differentiation, clinical stage and Ki-67. Besides, high VPS4B expression was an independent prognostic factor for NSCLC patients poor survival. To determine whether VPS4B could regulate the proliferation of NSCLC cells, we knocked down the expression of VPS4B and analyzed the proliferation of A549 NSCLC cells using Western blot, CCK8 and flow cytometry assays, which together indicated that loss of VPS4B could inhibit cell cycle progress. These data suggest that VPS4B may promote the progression of NSCLC and be a biotarget for NSCLCs therapy.
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SOX2 promotes tumor metastasis by stimulating epithelial-to-mesenchymal transition via regulation of WNT/?-catenin signal network.
Cancer Lett.
PUBLISHED: 03-20-2013
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SOX2 was reported to promote metastasis in various tumor tissues; however the underlying mechanisms remain elusive. Here, we disclosed that SOX2 improves metastasis of breast and prostate cancer cells by promoting epithelial-to-mesenchymal transition (EMT) through WNT/?-catenin, but not TGF-? or Snail1 signaling. Dual luciferase assay and chromatin immunoprecipitation revealed activation and binding of SOX2 on promoter region of ?-catenin. In addition, SOX2 affects the protein expression levels of DKK3, DVL1 and DVL3, which are regulators or downstream molecules of WNT signaling. Taken together, our findings demonstrated ?-catenin as one of vital downstream molecules that mediate the EMT induced by SOX2.
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589 nm laser generation by frequency doubling of a single-frequency Raman fiber amplifier in PPSLT.
Appl Opt
PUBLISHED: 03-13-2013
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A high-power single-frequency 1178 nm continuous-wave laser is generated in a two-stage stimulated-Brillouin-scattering-suppressed all-polarization-maintaining Raman fiber amplifier pumped by 1120 nm fiber lasers. A polarization-extinction-ratio of 30 dB is achieved due to the all-polarization-maintaining configuration and the polarization dependence gain of Raman scattering. Single-pass frequency doubling with a homemade periodically poled near-stoichiometric LiTaO(3) crystal (PPSLT) produces an up to 7 W narrow-linewidth laser at 589 nm. The thermally induced dephasing effect is found to be the key issue for improving second-harmonic efficiency.
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Expression and clinical role of small glutamine-rich tetratricopeptide repeat (TPR)-containing protein alpha (SGTA) as a novel cell cycle protein in NSCLC.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 02-26-2013
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A small glutamine-rich tetratricopeptide repeat-containing protein alpha (SGTA) is a 35 kDa protein involved in a number of biological processes. However, the role of SGTA in non-small-cell lung cancer (NSCLC) tumorigenesis has never been elucidated. The purpose of this study was to determine whether SGTA could serve as a biomarker for stratification and prediction of prognosis in NSCLC.
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Expression of SGTA Correlates with Prognosis and Tumor Cell Proliferation in Human Hepatocellular Carcinoma.
Pathol. Oncol. Res.
PUBLISHED: 01-19-2013
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To investigate the potential role of small glutamine-rich TPR-containing protein A (SGTA) in hepatocarcinogenesis, immunohistochemistry and Western blot were performed to detect the expression of SGTA in clinical Hepatocellular carcinoma (HCC) samples, adjacent nontumorous liver tissues and HCC cell lines. In addition, expression of SGTA was correlated with clinicopathological variables and univariate and multivariate survival analyses were performed to determine the prognostic significance. Moreover, the biological significance of the aberrant expression of SGTA was investigated in vitro. Both immunohistochemistry evaluation and Western blot analyses demonstrated that SGTA was overexpressed in HCC tissues compared with adjacent nontumorous liver tissues. Expression of SGTA directly correlated with the histological grades of HCC and high expression of SGTA was associated with a poor prognosis. SGTA depletion by siRNA inhibited cell proliferation, blocked S-phase and mitotic entry in Huh7 cells. Western blot analyses showed that SGTA depletion decreased cyclin A and cyclin B levels. Taken together, owing to overexpression of SGTA in HCC and its important role in predicting poor prognosis and the development of HCC, SGTA could be a potential prognostic marker and therapeutic target of HCC.
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miR-582-5p Is Upregulated in Patients with Active Tuberculosis and Inhibits Apoptosis of Monocytes by Targeting FOXO1.
PLoS ONE
PUBLISHED: 01-01-2013
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Macrophage apoptosis is a host innate defense mechanism against tuberculosis (TB). In this study, we found that percentage of apoptotic cells in peripheral blood monocytes from patients with active TB was lower than that from healthy controls (p<0.001). To understand whether microRNAs can modulate apoptosis of monocytes, we investigated differentially expressed microRNAs in patients with active TB. miR-582-5p was mainly expressed in monocytes and was upregulated in patients with active TB. The apoptotic percentage of THP-1 cells transfected with miR-582-5p mimics was significantly lower than those transfected with negative control of microRNA mimics (p<0.001), suggesting that miR-582-5p could inhibit apoptosis of monocytes. To our knowledge, the role of miR-582-5p in regulating apoptosis of monocytes has not been reported so far. Systematic bioinformatics analysis indicated that FOXO1 might be a target gene for miR-582-5p and its 3UTR contains potential binding sites for miR-582-5p. To determine whether miR-582-5p could influence FOXO1 expression, miR-582-5p mimics or negative control of microRNA mimics were transfected into THP-1 cells. RT-PCR and western blot analysis showed that the miR-582-5p could suppress both FOXO1 mRNA and protein expression. Co-transfection of miR-582-5p and FOXO1 3UTR-luciferase reporter vector into cells demonstrated that significant decrease in luciferase activity was only found in reporter vector that contained a wild type sequence of FOXO1 3UTR, suggesting that miR-582-5p could directly target FOXO1. In conclusion, miR-582-5p inhibited apoptosis of monocytes by down-regulating FOXO1 expression and might play an important role in regulating anti-M. tuberculosis directed immune responses.
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ERCC1 and ERCC2 haplotype modulates induced BPDE-DNA adducts in primary cultured lymphocytes.
PLoS ONE
PUBLISHED: 01-01-2013
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Benzo[a]pyrene(B[a]P), and its ultimate metabolite Benzo[a]pyrene 7,8-diol 9,10-epoxide (BPDE), are classic DNA damaging carcinogens. DNA damage caused by BPDE is normally repaired by Nucleotide Excision Repair (NER), of which ERCC1 and ERCC2/XPD exert an indispensable role. Genetic variations in ERCC1 and ERCC2 have been related to DNA repair efficiency. In this study we used lymphocytes from healthy individuals to show that polymorphisms in ERCC1 and ERCC2 are directly associated with decreased DNA repair efficiency.
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Ultra-performance liquid chromatography-tandem mass spectrometry method for the determination of nitrendipine in dog plasma and its application to a pharmacokinetic study of a solid self-emulsifying pellet formulation.
Arzneimittelforschung
PUBLISHED: 09-20-2011
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A rapid, sensitive and selective ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the quantitative determination of nitrendipine (NTD, CAS 39562-70-4) in dog plasma. Using propranolol hydrochloride (CAS 318-98-9) as an internal standard (IS), plasma samples pretreatment adopted a simple liquid-liquid extraction process with diethyl ether. Separation was carried out by a gradient elution on an Acquity UPLC BEH C18 column with a mobile phase consisting of water (containing 0.1% formic acid) and acetonitrile. Detection was performed by a triple-quadrupole mass spectrometry with positive electrospray ionization (ESI) as source ionization in multiple-reaction monitoring (MRM) mode at m/z 361.0 --> 315.0 for NTD and m/z 260.2 --> 116.0 for IS. The method demonstrated good linearity at the concentrations ranged from 0.1-200 ng/mL and the lower limit of quantification (LLOQ) of NTD was 0.1 ng/mL. The intra- and inter-day relative standard deviations (RSD) were less than 10%. The mean extraction recoveries of NTD and IS were 90.2% and 82.4%, respectively. Finally, the method was successfully applied to a pharmacokinetic study of home-made solid self-emulsifying pellets and conventional NTD tablets in beagle dogs following a single oral administration.
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Dual targeting folate-conjugated hyaluronic acid polymeric micelles for paclitaxel delivery.
Int J Pharm
PUBLISHED: 07-20-2011
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A series of novel self-assembled hyaluronic acid derivatives (HA-C(18)) grafted with hydrophobic octadecyl moiety and further dual targeting folic acid-conjugated HA-C(18) (FA-HA-C(18)) were synthesized. With the increase in the degree of substitution of octadecyl group from 12.7% to 19.3%, the critical micellar concentration of HA-C(18) copolymers decreased from 37.3 to 10.0 ?g/mL. Paclitaxel (PTX) was successfully encapsulated into the hydrophobic cores of the HA-C(18) and FA-HA-C(18) micelles, with encapsulation efficiency as high as 97.3%. The physicochemical properties of the polymeric micelles were measured by DLS, TEM and DSC. Moreover, in vitro release behavior of PTX was investigated by dialysis bag method and PTX was released from micelles in a near zero-order sustained manner. In vitro antitumor activity tests suggested PTX-loaded HA-C(18) and FA-HA-C(18) micelles exhibited significantly higher cytotoxic activity against MCF-7 and A549 cells compared to Taxol at a lower PTX concentration. The cellular uptake experiments were conducted by quantitative assay of PTX cellular accumulation and confocal laser scanning microscopy imaging of coumarin-6 labeled HA-C(18) and FA-HA-C(18) micelles in folate receptor overexpressing MCF-7 cells. Folate and CD44 receptor competitive inhibition studies performed by fluorescence microscopy imaging suggested intracellular delivery of HA-C(18) and FA-HA-C(18) micelles were efficiently taken up via CD44 receptor-mediated endocytosis. The folate receptor-mediated endocytosis further enhanced internalized amounts of FA-HA-C(18) micelles in MCF-7 cells, as compared with HA-C(18) micelles. The internalization pathways of PTX-loaded HA-C(18) and FA-HA-C(18) micelles might include clathrin-mediated endocytosis, caveolae-mediated endocytosis and macropinocytosis. Therefore, the present study suggested that HA-C(18) and FA-HA-C(18) copolymers as biodegradable, biocompatible and cell-specific targetable nanostructure carriers, are promising nanosystems for cellular and intracellular targeting delivery of hydrophobic anticancer drugs.
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Novel organic solvent-responsive expression vectors for biocatalysis: application for development of an organic solvent-tolerant biodesulfurizing strain.
Bioresour. Technol.
PUBLISHED: 06-09-2011
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Biodesulfurization is an attractive alternative to hydrodesulfurization for lowering the sulfur content of petroleum products. However, the fuel oils are toxic to microorganisms, which have seriously hindered the application of biodesulfurization. Here, a solvent-tolerant desulfurizing bacterium, Pseudomonas putida DS23, was developed using one of the organic solvent-responsive expression vectors newly constructed for biocatalysis, in which gene expression could be regulated in an organic solvent-dependent fashion. The biodesulfurizing activity of P. putida DS23 could be induced by all the organic solvents used. P. putida DS23 cells induced by n-hexane were able to degrade 56% of 0.5 mM DBT in 12 h in the biphasic reaction containing 33.3% (v/v) n-hexane, while the strain induced by isopropyl ?-D-1-thiogalactopyranoside could only degrade 26% of 0.5 mM DBT. These results suggested that use of the constructed organic solvent-responsive expression vectors can facilitate the biphasic biocatalysis involving organic solvents.
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A precise hexagonal octadecanuclear Ag macrocycle with significant luminescent properties.
Chem. Commun. (Camb.)
PUBLISHED: 05-31-2011
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The first hexagonal octadecanuclear Ag macrocycle [Ag(18)(TTTMB)(12)](NO(3))(18)·30H(2)O has been hydrothermally synthesized. The outside and inner diameters of the unprecedented architecture are about 27.72(13) Å and 15.37(7) Å, respectively. This complex displays a huge increase in the intensity and lifetime of phosphorescence with decreasing temperature.
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Cerenkov third-harmonic generation via cascaded ?(2) processes in a periodic-poled LiTaO? waveguide.
Opt Lett
PUBLISHED: 04-12-2011
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We report a type of quasi-phase-matched (QPM) Cerenkov third-harmonic generation (CTHG) in a periodic-poled LiTaO? waveguide. The CTHG results from a guided-to-guided second-harmonic generation cascaded with a guided-to-radiated sum-frequency generation (SFG) in the waveguide. In the guided-to-radiated SFG process, nonlinear interactions with participating and nonparticipating reciprocal vectors would lead to different CTHG radiations. In addition, the power and temperature detuning characters of QPM CTHG were studied. Theoretical predictions were in good agreement with experimental results.
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SOX2 promotes tumorigenesis and increases the anti-apoptotic property of human prostate cancer cell.
J Mol Cell Biol
PUBLISHED: 03-17-2011
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SRY-related HMG-box gene 2 (SOX2) is one of the key regulatory genes that maintain the pluripotency and self-renewal properties in embryonic stem cells. Here we used immunohistochemistry to analyze the expression of SOX2 in human prostate tissues and found it contributed to tumorigenesis and correlated with histologic grade and Gleason score. We further investigated SOX2s function in cell growth and apoptosis process by using a human prostate cancer cell line DU145 with SOX2 overexpression or down-regulation. Cell cycle assay revealed that SOX2 promoted cell growth and increased the percentage of cells in S phase. In vitro and in vivo xenograft experiments in NOD/SCID mice further demonstrated that SOX2 increased the apoptosis-resistant properties of DU145 cells with decreased function of store-operated Ca(2+) entry and reduced expression of Orai1 at both mRNA and protein levels, suggesting a potential mechanism that contributes to the anti-apoptotic property of SOX2. To our knowledge, this study is the first to investigate SOX2s function in tumorigenesis and apoptosis of human prostate cancer and to elucidate its regulatory effect on the activity of store-operated Ca(2+) channels. Our results support the concept that SOX2 has the potential to be a significant marker to evaluate the progression of prostate cancer and serve as a potentially useful target for prostate cancer therapy.
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(Z)-N-(2-Chloro-benzyl-idene)aniline N-oxide.
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 03-16-2011
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In the title compound, C(13)H(10)ClNO, the central C-N bond has considerable double-bond character and the N-O bond indicates a formal negative charge on the O atom. The mol-ecule is stabilized by an intra-molecular C-H?O hydrogen bond. The geometry about the C=N bond is Z [C-C-N-O torsion angle = -4.2?(3)°] and the phenyl and benzene rings are trans-oriented around the C=N bond. The phenyl and benzene rings make a dihedral angle of 56.99?(2)°.
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Bifunctional peptidomimetic prodrugs of didanosine for improved intestinal permeability and enhanced acidic stability: synthesis, transepithelial transport, chemical stability and pharmacokinetics.
Mol. Pharm.
PUBLISHED: 03-04-2011
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Five peptidomimetic prodrugs of didanosine (DDI) were synthesized and designed to improve bioavailability of DDI following oral administration via targeting intestinal oligopeptide transporter (PepT1) and enhancing chemical stability. The permeability of prodrugs was screened in Caco-2 cells grown on permeable supports. 5-O-L-valyl ester prodrug of DDI (compound 4a) demonstrated the highest membrane permeability and was selected as the optimal target prodrug for further studies. The uptake of glycylsarcosine (Gly-Sar, a typical substrate of PepT1) by Caco-2 cells could be inhibited by compound 4a in a concentration-dependent manner. The Caco-2 cells were treated with 0.2 nM leptin for enhanced PepT1 expression. The uptake of compound 4a was markedly increased in the leptin-treated Caco-2 cells compared with the control Caco-2 cells, both of which were obviously inhibited by 20 mM Gly-Sar. The K(m) and V(max) values of kinetic study of compound 4a transported by PepT1 in Caco-2 cells were 0.91 mM and 11.94 nmol/mg of protein/10 min, respectively. The chemical stability studies were performed in simulated gastric fluid (SGF), phosphate buffers under various pH conditions, rat tissue homogenates and plasma at 37 °C. The concentrations of DDI could not be detected in the two minutes in SGF. But compound 4a could significantly increase DDI acidic stability, and its t(½) was extended to as long as 36 min in SGF. Compound 4a was stable in pH 6.0 phosphate buffer but could be quickly transformed into DDI in plasma and tissue homogenates. The oral absolute bioavailability of DDI was 47.2% and 7.9% after compound 4a and DDI were orally administered to rats at a dose of 15 mg/kg, respectively. The coadministration with antiacid agent could also suggest that compound 4a was more stable under harsh acidic conditions compared with DDI. Compound 4a bioavailability in rats was reduced to 33.9% when orally co-administered with Gly-Sar (100 mg/kg). The In Vivo bioactivation mechanism of compound 4a was investigated by comparing the levels of DDI and compound 4a in the jugular and portal veins in rats. The plasma concentration of intact compound 4a was very low in portal veins and could hardly be detected in the jugular vein. In conclusion, compound 4a could significantly improve the oral bioavailability of DDI in rats through PepT1-mediated absorption and enhanced acidic stability, followed by rapid and mostly intracellular bioactivation, the majority in the intestinal cells but the minority in the liver. Additionally, the prodrug strategy targeted to intestinal PepT1 could offer a promising strategy to improve oral bioavailability of poorly absorbed didanosine.
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Neonatal overfeeding induced by small litter rearing causes altered glucocorticoid metabolism in rats.
PLoS ONE
PUBLISHED: 02-18-2011
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Elevated glucocorticoid (GC) activity may be involved in the development of the metabolic syndrome. Tissue GC exposure is determined by the tissue-specific GC-activating enzyme 11?-hydroxysteriod dehydrogenase type 1 (11?-HSD1) and the GC-inactivating enzyme 5?-reductase type 1 (5?R1), as well as 5?-reductase (5?R). Our aim was to study the effects of neonatal overfeeding induced by small litter rearing on the expression of GC-regulating enzymes in adipose tissue and/or liver and on obesity-related metabolic disturbances during development. Male Sprague-Dawley rat pup litters were adjusted to litter sizes of three (small litters, SL) or ten (normal litters, NL) on postnatal day 3 and then given standard chow from postnatal week 3 onward (W3). Small litter rearing induced obesity, hyperinsulinemia, and higher circulating corticosterone in adults. 11?-HSD1 expression and enzyme activity in retroperitoneal, but not in epididymal, adipose tissue increased with postnatal time and peaked at W5/W6 in both groups before declining. From W8, 11?-HSD1 expression and enzyme activity levels in retroperitoneal fat persisted at significantly higher levels in SL compared to NL rats. Hepatic 11?-HSD1 enzyme activity in SL rats was elevated from W3 to W16 compared to NL rats. Hepatic 5?R1 and 5?R expression was higher in SL compared to NL rats after weaning until W6, whereupon expression decreased in the SL rats and remained similar to that in NL rats. In conclusion, small litter rearing in rats induced peripheral tissue-specific alterations in 11?-HSD1 expression and activity and 5?R1 and 5?R expression during puberty, which could contribute to elevated tissue-specific GC exposure and aggravate the development of metabolic dysregulation in adults.
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Modulation of T cell cytokine production by miR-144* with elevated expression in patients with pulmonary tuberculosis.
Mol. Immunol.
PUBLISHED: 01-08-2011
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microRNAs have a critical role in regulating innate and adaptive immunity. To understand whether microRNAs play roles in regulating immune responses to Mycobacterium tuberculosis infection in humans, microRNA expression profiling was performed in PBMCs from pulmonary tuberculosis patients and healthy controls. Analysis of expression profiles showed that expression of 30 microRNAs was significantly altered during active TB as compared with healthy controls, 28 microRNAs were up-regulated and 2 microRNAs down-regulated. miR-144* was one of the microRNAs that were overexpressed in active TB patients. Real-time RT-PCR analysis showed that miR-144* was mainly expressed in T cells. Transfection of T cells with miR-144* precursor demonstrated that miR-144* could inhibit TNF-? and IFN-? production and T cell proliferation. It is concluded that miR-144* might involve in regulation of anti-TB immunity through modification of cytokine production and cell proliferation of T cells.
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Adiponectin levels in circulation and breast milk and mRNA expression in adipose tissue of preeclampsia women.
Hypertens Pregnancy
PUBLISHED: 12-21-2010
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Physiological insulin resistance occurs in normal pregnancy and is exaggerated in women with preeclampsia (PE). Adiponectin is a hormone with insulin-sensitizing, anti-atherogenic, and anti-inflammatory properties. Reports published on association between adiponectin levels and PE risk have been conflicting. This study sought to better determine the circulating adiponectin levels and its mRNA expression in adipose tissue in women with PE.
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Rapid detection of tobacco mosaic virus using the reverse transcription loop-mediated isothermal amplification method.
Arch. Virol.
PUBLISHED: 04-21-2010
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Tobacco mosaic virus (TMV) can cause a severe disease that is capable of greatly reducing tobacco quality and yield. In this study, a one-step reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for detection of TMV. The concentration of Mg(2+), reaction temperature and reaction time of the RT-LAMP were optimized to 5 mM, 65°C, and 60 min, respectively. The detection limit of the method was 100 times higher than that of RT-PCR. Visual inspection of RT-LAMP amplification demonstrated that positive and negative reactions exhibit distinctly different colours in daylight. Our results demonstrate that the method is stable, sensitive and specific.
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Reduced CD27 expression on antigen-specific CD4+ T cells correlates with persistent active tuberculosis.
J. Clin. Immunol.
PUBLISHED: 01-16-2010
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CD27, a member of the tumor necrosis factor receptor family, has important role in generation of T cell immunity. In this study, association of CD27 expression on mycobacterial antigen-specific CD4+ T cells with pulmonary tuberculosis (TB) was investigated.
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Strong humoral response elicited by a DNA vaccine targeting gastrin-releasing peptide with optimized adjuvants inhibits murine prostate carcinoma growth in vivo.
Endocr. Relat. Cancer
PUBLISHED: 07-31-2009
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Previous studies demonstrated that the elevated expression and receptor binding of gastrin-releasing peptide (GRP) in various types of cancer suggest that GRP might be a putative target for immunotherapy in neoplastic diseases. DNA vaccine for hormone/growth factor immune deprivation represents a feasible and attractive approach for cancer treatment; nevertheless, there is still a need to increase the potency of the DNA vaccine. Here, based on six copies of the B cell epitope GRP(18-27) in a linear alignment as an immunogen, we designed several anti-GRP DNA vaccines containing different combinations of immunoadjuvants, such as HSP65, tetanus toxoid(830-844) (T), pan HLA-DR-binding epitope (PADRE) (P), and mycobacterial HSP70(407-426) (M), on a backbone of pCR3.1 plasmid vector with eight 5-GACGTT-3 CpG motifs and the VEGF183 signal peptide (VS). The effects of these immunoadjuvants in enhancing GRP-specific humoral immune response were then evaluated by comparing the respective immunogenicity and antitumor effects. Immunization of mice with pCR3.1-VS-HSP65-TP-GRP6-M2 elicited much higher levels of specific anti-GRP antibodies and more effectively inhibited the growth of a GRP-dependent tumor RM-1 in vivo. Interestingly, plasmids encoding for 2HSP70(407-426), but not the one with 1 or 3HSP70(407-426) showed stronger immune stimulatory potential as well as impressive antitumor activity, suggesting that 2HSP70(407-426) is an efficient molecular adjuvant for developing self-epitope vaccines. The highly immunogenic, potent anti-tumorigenic and antiangiogenesis activities of the anti-GRP DNA vaccine offered a novel immunotherapeutic approach in the treatment of GRP-dependent tumors and their complications.
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NOx removal from vehicle emissions by functionality surface of asphalt road.
J. Hazard. Mater.
PUBLISHED: 06-27-2009
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This paper reported the potential of heterogeneous photocatalysis as an advanced oxidation technology for NO(x) removal from vehicle emissions by using TiO(2) as a photocatalyst immobilized on the surface of asphalt road. Based on asphalt road material porous characteristic, we utilized permeability technology to make asphalt nano-TiO(2) to be environmental protection materials. And then using scanning electron microscope, we observed the penetrating effect of TiO(2). The effect of surface friction, humidity and light intensity on NO(x) removal had been systematically investigated by the use of TiO(2) immobilized on the surface of asphalt road as photocatalytic environmental protection materials. In addition, the decontaminating effect was tested by contrast test in TiO(2) spraying section with non-spraying section, while the productions were used in road environment. Results of experiment revealed that decontaminating rate of the productions ranged from 6% to 12% this kind of photochemical catalysis environmental protection material has good environment purification function.
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Solid self-emulsifying nitrendipine pellets: preparation and in vitro/in vivo evaluation.
Int J Pharm
PUBLISHED: 05-27-2009
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Objective of this study is to develop and evaluate the new solid self-emulsifying (SE) pellets of poorly soluble nitrendipine (NTD). These pellets were prepared via extrusion/spheronization technique, using liquid SEDDS (NTD, Miglyol 812, Cremophor RH 40, Tween 80, and Transcutol P), adsorbents (silicon dioxide and crospovidone), microcrystalline cellulose and lactose. The resulting SE pellets with 30% liquid SEDDS exhibited uniform size (800-1000 microm) and round shape, droplet size distribution following self-emulsification was nearly same to the liquid SEDDS (72+/-16 nm and 64+/-12 nm). The in vitro release was similar for the two SE formulations (over 80% within 30 min), both significantly higher than the conventional tablets (only 35% within 30 min). The oral bioavailability was evaluated for the SE pellets, liquid SEDDS and conventional tablets in fasted beagle dogs. AUC of NTD from the SE pellets showed 1.6-fold greater than the conventional tablets and no significant difference compared with the liquid SEDDS. In conclusion, our studies illustrated that extrusion/spheronization technique could be a useful large-scale producing method to prepare the solid SE pellets from liquid SEDDS, which can improve oral absorption of NTD, nearly equivalent to the liquid SEDDS, but better in the formulation stability, drugs leakage and precipitation, etc.
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Specific antibodies elicited by a novel DNA vaccine targeting gastrin-releasing peptide inhibit murine melanoma growth in vivo.
Clin. Vaccine Immunol.
PUBLISHED: 05-20-2009
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The elevated expression and receptor binding of gastrin-releasing peptide (GRP) in various types of cancer, especially in malignant melanoma of the skin, suggest that GRP might be a putative target for immunotherapy in neoplastic diseases. We have therefore constructed a novel DNA vaccine coding for six tandem repeats of a fragment of GRP from amino acids 18 to 27 (GRP6) flanked by helper T-cell epitopes for increased immunogenicity, including HSP65, a tetanus toxoid fragment from amino acids 830 to 844 (T), pan-HLA-DR-binding epitope (PADRE) (P), and two repeats of a mycobacterial HSP70 fragment from amino acids 407 to 426 (M). The anti-GRP DNA vaccine (pCR3.1-VS-HSP65-TP-GRP6-M2) was constructed on a backbone of a pCR3.1 plasmid vector with eight 5-GACGTT-3 CpG motifs and the VEGF183 signal peptide (VS). Intramuscular (IM) injections of anti-GRP vaccine in mice stimulated the production of high titers of specific antibodies against GRP and suppressed the growth of subcutaneous tumors of B16-F10 melanoma cells. Parallel results were obtained in vitro, showing inhibition of B16-F10 cell proliferation by GRP antisera. IM injections of the DNA vaccine also significantly attenuated tumor-induced angiogenesis associated with intradermal tumors of B16-F10 cells. In addition, lung invasion of intravenously injected cells was highly diminished, suggesting potent antimetastatic activity of the DNA vaccine. These findings support the highly immunogenic and potent antitumorigenic activity of specific anti-GRP antibodies elicited by the anti-GRP DNA vaccine.
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A novel human parathyroid hormone (1-34) analog for the treatment of osteoporosis.
Peptides
PUBLISHED: 01-06-2009
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The more effective bioactive peptides which can be efficiently prepared with low cost and high yield are in great demand for the development of therapeutic peptides. In this study, Pro-Pro-[Arg(11)]hPTH(1-34)-Pro-Pro-Asp (hPTH), an analog of human parathyroid hormone (1-34) [hPTH(1-34)], was prepared by an efficiently cost-effective preparation strategy. It was repeated eight times on the gene level and expressed in the form of inclusion bodies in Escherichia coli. Following some primary purifications, the inclusion bodies of octapeptide repeats were hydrolyzed into hPTH monomers by hydrochloric acid. After further purified by a CM52 chromatographic column, hPTH reached a yield of 16.9% and output of 61 mg/l medium. Furthermore, we compared anabolic effects between hPTH and hPTH(1-34) on ovariectomized rats. The results indicated that hPTH led to more significant increments in bone material density (BMD), trabecular width and bone formation marker as well as less loss in marrow space area than what hPTH(1-34) did. In addition, the active form of hPTH was introduced by the excision with dipeptidyl peptidase IV in vivo. These results suggest that hPTH is more effective than hPTH(1-34) in stimulating bone formation and improving skeletal microarchitecture. We can conclude that hPTH is potentially a more effective therapeutical agent on osteoporosis.
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Excision repair of BPDE-adducts in human lymphocytes: diminished capacity associated with ERCC1 C8092A (rs3212986) polymorphism.
Arch. Toxicol.
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Benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE), a metabolite of Benzo[a]pyrene (B[a]P), is a high-risk factor for development of a number of cancers. DNA damage caused by BPDE is normally repaired by Nucleotide Excision Repair system of which ERCC1 exerts an important role. We investigated whether two single nucleotide polymorphisms in ERCC1 (C19007T; rs11615 and C8092A; rs3213986) affected the repair efficacy of BPDE-DNA adducts. We collected peripheral blood of 780 healthy individuals from the northeast of China and detected the genotypes of rs11615 and rs3213986. The amount of induced BPDE-DNA adducts in lymphocytes from 117 randomly selected participants was assessed by HPLC. Presence of BPDE-DNA adducts in nucleus of lymphocytes was visualized using the modified comet assay. ERCC1 and CAST (3 adjacent gene of ERCC1) mRNA expression levels were quantified after in vitro exposure to BPDE. We found that the minor A allele in rs3212986 was related to higher levels of BPDE-DNA adducts and holistic marking DNA damage (P < 0.01). Haplotype CA (rs11615 and rs3213986) was also associated with an elevated risk of high BPDE-DNA adduct levels (OR = 1.801, 95 % CI of OR 1.191-2.724). Interestingly, in participants with AA genotype for rs3213986, CAST mRNA level was decreased compared to individuals with the homozygous CC genotype. Our findings suggests that ERCC1 C8092A (rs3213986) is associated with a diminished capacity of repairing BPDE-DNA adducts and may be used as a valid biomarker to predict an individuals risk to develop cancer upon exposure to environmental carcinogens.
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Association of genetic polymorphisms in ERCC1 and ERCC2/XPD with risk of chronic benzene poisoning in a Chinese occupational population.
Mutat. Res.
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DNA damage induced by benzene and its metabolites is thought of as an important mechanism underlying benzene genotoxicity in chronic benzene poisoning (CBP). Therefore, genetic variation in DNA repair genes may contribute to susceptibility to CBP in the exposed population. Since benzene-induced DNA damages include DNA adducts, we hypothesized that the polymorphisms of ERCC1 (Excision repair cross complementation group 1) and ERCC2/XPD (Excision repair cross complementation group 2/xeroderma pigmentosum group D) are associated with the risk of CBP. A case-control study involving 102 benzene-poisoned patients and 204 none-benzene-poisoned controls occupationally exposed to benzene was carried out in the Northeast region of China. The polymorphisms of codon 118 (rs11615) and C8092A (rs3212986) of ERCC1, codon 751 (rs13181), 312 (rs1799793) and 156 (rs238406) of ERCC2/XPD were genotyped by TaqMan(®) Real-time PCR. The results showed that individuals carrying the ERCC1 codon 118 TT genotype had an increased risk of CBP (OR(adj)=3.390; 95%CI: 1.393-8.253; P=0.007) comparing with its CC genotype. After stratified by smoking, gender and exposure duration we found that the increased risk of CBP associated with the ERCC1 codon 118 TT genotype confined to nonsmokers (OR=3.214; 95% CI: 1.359-7.601; P=0.006), female (OR=3.049; 95% CI: 1.235-7.529; P=0.013) and exposure duration> 12 years (OR=3.750; 95% CI: 1.041-13.513; P=0.035). Since ERCC1 and ERCC2/XPD are both located on chromosome 19q13.3, haplotype analysis of all 5 SNPs was also conducted. However no correlations between the risks of CBP and other genotypes or haplotypes were found. Therefore, our findings suggest an important role of ERCC1 codon 118 polymorphisms for a biomarker to CBP in the Chinese occupational population.
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Human embryonic stem cell-derived endothelial cells as cellular delivery vehicles for treatment of metastatic breast cancer.
Cell Transplant
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Endothelial progenitor cells (EPCs) have shown tropism towards primary tumors or metastases and are thus potential vehicles for targeting tumor therapy. However, the source of adult EPCs is limited, which highlights the need for a consistent and renewable source of endothelial cells for clinical applications. Here, we investigated the potential of human embryonic stem cell-derived endothelial cells (hESC-ECs) as cellular delivery vehicles for therapy of metastatic breast cancer. In order to provide an initial assessment of the therapeutic potency of hESC-ECs, we treated human breast cancer MDA-MB-231 cells with hESC-EC conditioned medium (EC-CM) in vitro. The results showed that hESC-ECs could suppress the Wnt/?-catenin signaling pathway and thereby inhibit the proliferation and migration of MDA-MB-231 cells. To track and evaluate the possibility of hESC-EC-employed therapy, we employed the bioluminescence imaging (BLI) technology. To study the therapeutic potential of hESC-ECs, we established lung metastasis models by intravenous injection of MDA-MB-231 cells labeled with firefly luciferase (Fluc) and green fluorescent protein (GFP) to NOD/SCID mice. In mice with lung metastases, we injected hESC-ECs armed with herpes simplex virus truncated thymidine kinase (HSV-ttk) intravenously on days 11, 16, 21, and 26 after MDA-MB-231 cell injection. The NOD/SCID mice were subsequently treated with ganciclovir (GCV), and the growth status of tumor was monitored by Fluc imaging. We found that MDA-MB-231 tumors were significantly inhibited by intravenously injected hESC-ECs. The tumor-suppressive effects of the hESC-ECs, by inhibiting Wnt/?-catenin signaling pathway and inducing tumor cell death through bystander effect in human metastatic breast cancer model, provide previously unexplored therapeutic modalities for cancer treatment.
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Assessment of therapeutic efficacy of liposomal nanoparticles mediated gene delivery by molecular imaging for cancer therapy.
J Biomed Nanotechnol
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The inadequate treatment efficacy, suboptimal cancer detection and disease monitoring in anticancer therapies have led to the quest for clinically relevant, innovative multifaceted solutions such as development of targeted and traceable approaches. Molecular imaging technologies with the versatility of liposomal nanoparticles platform offer tangible options to better guide treatment delivery and monitor outcome. In this study, we introduced noninvasive, quantitative and functional imaging techniques with reporter gene methods to probe breast cancer processes with liposomal nanoparticles by bioluminescence imaging (BLI). A breast cancer model was applied for therapy by injecting 5.0 x 10(5) 4T1 cells carrying a reporter system encoding a double fusion reporter gene consisting of firefly luciferase (Fluc) and green fluorescent protein (GFP) into BALB/c mice. Liposomal nanoparticles loaded with a triple fusion gene containing the herpes simplex virus truncated thymidine kinase (HSV-ttk) and renilla luciferase (Rluc) and red fluorescent protein (RFP) were applied by in situ injection for monitoring and evaluating gene therapy. The BALB/c mice were subsequently treated with ganciclovir (GCV) and the growth status of tumor was monitored by bioluminescence imaging of Fluc and the treatment delivery of liposomal nanoparticle was efficiently tracked by Rluc imaging. In fact, TF plasmids were shown to be useful for monitoring and evaluating targeting efficacy and gene therapy by non-invasive molecular imaging. In conclusion, the combination of noninvasive imaging techniques and liposomal nanoparticle can provide a practical and clinically useful way for gene delivery and monitoring the level of gene expression over time and treatment response in patients undergoing gene therapy.
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Trimethylsilyl chloride promoted synthesis of ?-branched amines by nucleophilic addition of organozinc halides to nitrones.
Org. Biomol. Chem.
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A general procedure for the nucleophilic addition of organozinc halides with nitrones in the presence of trimethylsilyl chloride has been developed. Trimethylsilyl chloride was found to be both an indispensable reaction promoter and a ready hydroxylamine protective agent in these reactions. The produced O-(trimethylsilyl)hydroxylamines can be easily reduced into corresponding amines just by a zinc-copper couple in saturated aqueous NH(4)Cl solution.
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The effects of dietary fatty acid composition in the post-sucking period on metabolic alterations in adulthood: can ?3 polyunsaturated fatty acids prevent adverse programming outcomes?
J. Endocrinol.
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Early life nutrition is important in the regulation of metabolism in adulthood. We studied the effects of different fatty acid composition diets on adiposity measures, glucose tolerance, and peripheral glucocorticoid (GC) metabolism in overfed neonatal rats. Rat litters were adjusted to a litter size of three (small litters (SLs)) or ten (normal litters (NLs)) on postnatal day 3 to induce overfeeding or normal feeding respectively. After weaning, SL and NL rats were fed a ?6 polyunsaturated fatty acid (PUFA) diet (14% calories as fat, soybean oil) or high-saturated fatty acid (high-fat; 31% calories as fat, lard) diet until postnatal week 16 respectively. SL rats were also divided into the third group fed a ?3 PUFA diet (14% calories as fat, fish oil). A high-fat diet induced earlier and/or more pronounced weight gain, hyperphagia, glucose intolerance, and hyperlipidemia in SL rats compared with NL rats. In addition, a high-fat diet increased 11?-hsd1 (Hsd11b1) mRNA expression and activity in the retroperitoneal adipose tissue of both litter groups compared with standard chow counterparts, whereas high-fat feeding increased hepatic 11?-hsd1 mRNA expression and activity only in SL rats. SL and a high-fat diet exhibited significant interactions in both retroperitoneal adipose tissue and hepatic 11?-HSD1 activity. Dietary ?3 PUFA offered protection against glucose intolerance and elevated GC exposure in the retroperitoneal adipose tissue and liver of SL rats. Taken together, the results suggest that dietary fatty acid composition in the post-sucking period may interact with neonatal feeding and codetermine metabolic alterations in adulthood.
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SOX2 gene regulates the transcriptional network of oncogenes and affects tumorigenesis of human lung cancer cells.
PLoS ONE
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Recent studies demonstrated that cancer stem cells (CSCs) have higher tumorigenesis properties than those of differentiated cancer cells and that transcriptional factor-SOX2 plays a vital role in maintaining the unique properties of CSCs; however, the function and underlying mechanism of SOX2 in carcinogenesis of lung cancer are still elusive. This study applied immunohistochemistry to analyze the expression of SOX2 in human lung tissues of normal individuals as well as patients with adenocarcinoma, squamous cell carcinoma, and large cell and small cell carcinoma and demonstrated specific overexpression of SOX2 in all types of lung cancer tissues. This finding supports the notion that SOX2 contributes to the tumorigenesis of lung cancer cells and can be used as a diagnostic probe. In addition, obviously higher expression of oncogenes c-MYC, WNT1, WNT2, and NOTCH1 was detected in side population (SP) cells than in non-side population (NSP) cells of human lung adenocarcinoma cell line-A549, revealing a possible mechanism for the tenacious tumorigenic potential of CSCs. To further elucidate the function of SOX2 in tumorigenesis of cancer cells, A549 cells were established with expression of luciferase and doxycycline-inducible shRNA targeting SOX2. We found silencing of SOX2 gene reduces the tumorigenic property of A549 cells with attenuated expression of c-MYC, WNT1, WNT2, and NOTCH1 in xenografted NOD/SCID mice. By using the RNA-Seq method, an additional 246 target cancer genes of SOX2 were revealed. These results present evidence that SOX2 may regulate the expression of oncogenes in CSCs to promote the development of human lung cancer.
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CD44 antibody-targeted liposomal nanoparticles for molecular imaging and therapy of hepatocellular carcinoma.
Biomaterials
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Most hepatocellular carcinoma (HCC) therapies fail to target cancer stem cells (CSCs) and monitor cancer progression or regression. The purpose of this study was to evaluate the possibility of cancer imaging and simultaneously monitoring targeted therapy in a single animal by anti-CD44 antibody-mediated liposomal nanoparticle. In this study, an in situ liver tumor model was applied for therapy by injecting 1.0 × 10(6) HepG2 cells carrying a reporter system encoding a double fusion (DF) reporter gene consisting of firefly luciferase (Fluc) and green fluorescent protein (GFP) into the liver of NOD/SCID mice. A strategy was developed which specifically targeted HCC via anti-CD44 antibody-mediated liposomal nanoparticle delivery, loaded of either doxorubicin (Dox) or a triple fusion (TF) gene containing the herpes simplex virus truncated thymidine kinase (HSV-ttk) and renilla luciferase (Rluc) and red fluorescent protein (RFP). The NOD/SCID mice were subsequently treated with ganciclovir (GCV) and the growth status of tumor was monitored by optical bioluminescence imaging (BLI) of Fluc and specific targeting of the liposomal nanoparticle was tracked by Rluc imaging. CD44 antibody-mediated liposomal nanoparticle, loaded of TF plasmids, were shown to be useful for monitoring and evaluating targeting efficacy and gene therapy by non-invasive molecular imaging. Here, we demonstrate the time intensive preclinical steps involved in molecular target identification, validation, and characterization by dual molecular imaging. This targeted and traceable therapeutic strategy has potential advantages to overcome the problems of conventional tumor therapy and may open a new application for the treatment of HCC by targeting CSCs.
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Legumain: a biomarker for diagnosis and prognosis of human ovarian cancer.
J. Cell. Biochem.
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Legumain is a member of the asparaginyl endopeptidase family that is over-expressed in response to hypoxic stress on mammary adenocarcinoma, colorectal cancer, proliferating endothelial cells, and tumor-associated macrophages (TAMs). Here, we demonstrate that elevated expression of legumain in ovarian cancer by a proteomic approach using isobaric tags for relative and absolute quantification (iTRAQ) followed by liquid chromatography-mass spectrometry (LC-MS/MS). To investigate the relationship between legumain expression and ovarian cancer development, we tested legumain expression in malignant human ovarian tumors (n?=?60), borderline ovarian tumors (n?=?20), benign ovarian tumors (n?=?20), and normal ovary samples (n?=?20) using immunohistochemical assay (IHC). A correlation between legumain expression, and clinocopathologic and biological variables was also established. Importantly, increased legumain expression was validated by real-time PCR and Western blots, correlated positively with an increased malignancy of ovarian tumors (P?
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Activating transcription factor 4 increases chemotherapeutics resistance of human hepatocellular carcinoma.
Cancer Biol. Ther.
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It has been reported that activating transcription factor 4 (ATF4) increases the processes of tumor growth, metastasis and drug resistance. However, the role played by ATF4 in chemoresistance of hepatocellular carcinoma (HCC) remains unknown. Clarification of this role of ATF4 in HCC could greatly benefit the efficacy of clinical treatment of HCC. In this study, we found that ATF4 was overexpressed in about 50.7% of HCC tissues. In fact knockdown of ATF4 significantly increased the cytotoxicity of cisplatin in both in vitro and in vivo assays, while overexpression of this molecule dramatically decreased the sensitivity of HCC cell lines to cisplatin. Additionally, we found that synthesis of glutathione was significantly reduced in HCC cell lines subjected to ATF4 knockdown. Taken together, these results demonstrate that ATF4 can increase resistance to cisplatin in HCC by increased biosynthesis of glutathione, and that this may be a potent novel target for the future development of anti-HCC drugs.
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Resemblance of symptoms for major depression assessed at interview versus from hospital record review.
PLoS ONE
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Diagnostic information for psychiatric research often depends on both clinical interviews and medical records. Although discrepancies between these two sources are well known, there have been few studies into the degree and origins of inconsistencies.
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Gold nanoparticles with asymmetric polymerase chain reaction for colorimetric detection of DNA sequence.
Anal. Chem.
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We developed a novel strategy for rapid colorimetric analysis of a specific DNA sequence by combining gold nanoparticles (AuNPs) with an asymmetric polymerase chain reaction (As-PCR). In the presence of the correct DNA template, the bound oligonucleotides on the surface of AuNPs selectively hybridized to form complementary sequences of single-stranded DNA (ssDNA) target generated from As-PCR. DNA hybridization resulted in self-assembly and aggregation of AuNPs, and a concomitant color change from ruby red to blue-purple occurred. This approach is simpler than previous methods, as it requires a simple mixture of the asymmetric PCR product with gold colloid conjugates. Thus, it is a convenient colorimetric method for specific nucleic acid sequence analysis with high specificity and sensitivity. Most importantly, the marked color change occurs at a picogram detection level after standing for several minutes at room temperature. Linear amplification minimizes the potential risk of PCR product cross-contamination. The efficiency to detect Bacillus anthracis in clinical samples clearly indicates the practical applicability of this approach.
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What is Visualize?

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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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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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.