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Find video protocols related to scientific articles indexed in Pubmed.
Hierarchical superstructures from a star-shaped molecule consisting of a cyclic oligosiloxane with cyanobiphenyl moieties.
Soft Matter
PUBLISHED: 11-20-2014
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Unconventional star-shaped liquid crystals (abbreviated as SiLCs) were successfully synthesized by chemically connecting four cyanobiphenyl anisotropic mesogens to the periphery of a super-hydrophobic and ultra-flexible cyclic tetramethyltetrasiloxane ring with flexible hexyl chains. Based on the combined experimental techniques of differential scanning calorimetry (DSC), cross-polarized optical microscopy (POM), solid-state carbon-13 ((13)C) nuclear magnetic resonance (NMR) spectroscopy and one-dimensional (1D) wide-angle X-ray diffraction (WAXD), it was found that the SiLC molecule exhibited the monotropic phase transition from a LC phase to a crystalline phase. The crystalline phase was only detected during slow heating processes above its glass transition temperature, while a LC phase was formed both during cooling and during heating processes. The hierarchical superstructures were identified from the structure-sensitive 2D WAXD of the macroscopically oriented SiLC film and confirmed by selected area electron diffraction (SAED) of the SiLC single crystals. The molecular packing symmetry in the monoclinic unit cell was further investigated by computer simulations on the real and reciprocal spaces. Macroscopically oriented SiLC hierarchical superstructures on the different length scales may provide the targeted physical properties, which can allow us to apply SiLC molecules in the fields of electro-optical devices and nonlinear optics.
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Titanium nanoparticles inhalation induces renal fibrosis in mice via an oxidative stress-up-regulated transforming growth factor-? pathway.
Chem. Res. Toxicol.
PUBLISHED: 11-19-2014
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Titanium dioxide nanoparticles (Nano-TiO2) are gradually extensively used in the clinical, industry and daily life. Accumulation studies showed that Nano-TiO2 exposure is able to cause injuries in various animal organs, including lung, liver, spleen, and kidney. However, it remains unclear whether exposure of Nano-TiO2 by inhalation causes renal fibrosis. Here, we investigated the role of reactive oxygen species (ROS)/reactive nitrogen species (RNS)-related signalling molecules in the chronic renal damage after Nano-TiO2 inhalation in mice. Mice were treated with Nano-TiO2 (0.1, 0.25, and 0.5 mg/week) or microparticle-TiO2 (0.5 mg/week) by non-surgical intratracheal instillation for 4 weeks. The results showed that Nano-TiO2 inhalation increased renal pathological changes in a dose-dependent manner. No renal pathological changes were observed in microparticle-TiO2-instilled mice. Nano-TiO2 (0.5 mg/week) possessed the ability to precipitate in the kidneys determined by transmission electron microscopy and increased serum levels of blood urea nitrogen. The expressions of markers of ROS/RNS and renal fibrosis markers, including nitrotyrosine, inducible nitric oxide synthase, hypoxia inducible factor-1? (HIF-1?), heme oxygenase 1, transforming growth factor-? (TGF?), and collagen I determined by immunohistochemical staining were increased in the kidneys. Furthermore, Nano-TiO2-induced renal injury could be mitigated by iNOS inhibitor aminoguanidine and ROS scavenger N-acetylcysteine treatment in transcription level. The in vitro experiments showed that Nano-TiO2 significantly and dose-dependently increased the ROS production and the expressions of HIF-1??and TGF? in human renal proximal tubular cells, which could be reversed by N-acetylcysteine treatment. Taken together, these results suggest Nano-TiO2 inhalation might induce the renal fibrosis through a ROS/RNS-related HIF-1?-up-regulated TGF-? signalling pathway.
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Proliferative epithelial disease identified in nipple aspirate fluid and risk of developing breast cancer: A systematic review.
Curr Med Res Opin
PUBLISHED: 11-19-2014
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Abstract Background: Guideline panels recognize the need to increase the accuracy of identifying women at high risk of developing breast cancer who would benefit from prevention strategies. The characterization of proliferative epithelial disease found in nipple aspirate fluid (PED-NAF) may be a relevant risk factor. Objective: To comprehensively review the published literature to characterize and summarize abnormal cytology detected by NAF and the association of PED-NAF with subsequent risk of developing breast cancer. Research design and methods: Literature identified by systematic searches in MEDLINE PubMed and the Cochrane Library was screened for articles containing primary data on NAF cytology based on predefined inclusion and exclusion criteria. Main outcome measures: Study characteristics, cytological group distribution, and incidence of breast cancer. Results: Thirty articles were included after full-text review, of which 16 were analyzed, containing data on 20,808 unique aspirations from over 17,378 subjects. Seven (44%) of the studies used the King cytological classification system. Among aspirations from women free of breast cancer, 51.5% contained fluid, in which over 27.7% had PED on cytology. In the 2 prospective studies of 7,850 cancer-free women, abnormal cytology by NAF carried a 2.1-fold higher risk (95% CI, 1.6-2.6; p < 0.001) of developing breast cancer, compared with women from whom no fluid could be obtained. Conclusions: PED-NAF among women free of breast cancer, compared with no fluid being obtained, has an independent risk of developing breast cancer comparable to the risk of a woman with a positive family history of breast cancer. These findings have implications for augmenting risk prediction and clinical decisions concerning breast cancer surveillance and chemoprevention. As with all reviews, heterogeneity across studies may have influenced the results. The limited literature calls for prospective studies on asymptomatic women with long-term follow-up.
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Role of P-selectin and P-selectin glycoprotein ligand-1 interaction in the induction of tissue factor expression on human platelets after incubation with porcine aortic endothelial cells.
Xenotransplantation
PUBLISHED: 11-19-2014
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Development of coagulation disorders remains a major challenge in pig-to-primate organ xenotransplantation. Our previous studies demonstrated that porcine aortic endothelial cells (pAEC) activate human platelets to express tissue factor (TF). In this study, we investigated the molecular interaction between human platelets and pAEC to identify possible targets for further genetic modification and/or systemic therapy. Human platelets were incubated with pAEC from wild-type (WT), ?1,3-galactosyltransferase gene-knockout (GTKO), and GTKO pigs expressing human CD46, after which the platelets were analyzed for TF expression, TF mRNA level and TF function. pAEC were analyzed for von Willebrand factor (vWF) expression and mRNA level as well. Neutralizing antibodies for P-selectin and P-selectin glycoprotein ligand-1 (PSGL-1) were used to block the molecular interaction between platelets and pAEC. GTKO and GTKO/CD46 pAEC-activated human platelets to induce human TF activity equivalently to WT pAEC. Simultaneously, after incubation with pAEC, platelets co-expressed TF and P-selectin. TF expression was blocked when pAEC and platelets were pre-incubated with anti-human P-selectin or anti-human PSGL-1 antibodies, but not by anti-porcine P-selectin antibody. Activated pAEC up-regulated TF on platelets through the interaction of porcine vWF with the human GPIb receptor. Up-regulation of TF on human platelets by GTKO and GTKO/CD46 pAEC was comparable to that by WT pAEC, which is associated with concomitant expression of P-selectin and PSGL-1, forming an auto-augmented loop of pAEC and platelet activation. Blocking of P-selectin and PSGL-1 interaction may be required to prevent up-regulation of recipient TF in vivo after organ xenotransplantation.
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Resistin promotes tumor metastasis by down-regulation of miR-519d through the AMPK/p38 signaling pathway in human chondrosarcoma cells.
Oncotarget
PUBLISHED: 11-06-2014
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Resistin is a recently discovered adipocyte-secreting adipokine, which may play a critical role in modulating cancer pathogenesis. Chondrosarcoma is a highly malignant tumor known to frequently metastasize; however, the role of resistin in the metastasis of human chondrosarcoma is largely unknown. Here, we found that the expression of resistin was higher in chondrosarcoma biopsy tissues than in normal cartilage. Moreover, treatment with resistin increased matrix metalloproteinase (MMP)-2 expression and promoted cell migration in human chondrosarcoma cells. Co-transfection with microRNA (miR)-519d mimic resulted in reversed resistin-mediated cell migration and MMP-2 expression. Additionally, AMP-activated protein kinase (AMPK) and p38 inhibitors or siRNAs reduced the resistin-increased cell migration and miR-519d suppression, and inhibition of resistin expression resulted in suppression of MMP-2 expression and lung metastasis in vivo. Taken together, our results indicate that resistin promotes chondrosarcoma metastasis and MMP-2 expression through activation of the AMPK/p38 signaling pathway and down-regulation of miR-519d expression. Therefore, resistin may represent a potential novel molecular therapeutic target in chondrosarcoma metastasis.
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Antimicrobial resistance of Escherichia coli isolates from canine urinary tract infections.
J. Vet. Med. Sci.
PUBLISHED: 10-31-2014
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This study determined the antimicrobial resistance profiles of Escherichia coli isolates from dogs with a presumptive diagnosis of urinary tract infection (UTI). Urine samples from 201 dogs with UTI diagnosed through clinical examination and urinalysis were processed for isolation of Escherichia coli. Colonies from pure cultures were identified by biochemical reactions (n=114) and were tested for susceptibility to 18 antimicrobials. The two most frequent antimicrobials showing resistance in Urinary E. coli isolates were oxytetracycline and ampicillin. Among the resistant isolates, 17 resistance patterns were observed, with 12 patterns involving multidrug resistance (MDR). Of the 69 tetracycline-resistant E. coli isolates, tet(B) was the predominant resistance determinant and was detected in 50.9% of the isolates, whereas the remaining 25.5% isolates carried the tet(A) determinant. Most ampicillin and/or amoxicillin-resistant E. coli isolates carried blaTEM-1 genes. Class 1 integrons were prevalent (28.9%) and contained previously described gene cassettes that are implicated primarily in resistance to aminoglycosides and trimethoprim (dfrA1, dfrA17-aadA5). Of the 44 quinolone-resistant E. coli isolates, 38 were resistant to nalidixic acid, and 6 were resistant to nalidixic acid, ciprofloxacin and enrofloxacin. Chromosomal point mutations were found in the GyrA (Ser83Leu) and ParC (Ser80Ile) genes. Furthermore, the aminoglycoside resistance gene aacC2, the chloramphenicol resistant gene cmlA and the florfenicol resistant gene floR were also identified. This study revealed an alarming rate of antimicrobial resistance among E. coli isolates from dogs with UTIs.
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CCL5/CCR5 axis induces vascular endothelial growth factor-mediated tumor angiogenesis in human osteosarcoma microenvironment.
Carcinogenesis
PUBLISHED: 10-22-2014
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Chemokines modulate angiogenesis and metastasis that dictate cancer development in tumor microenvironment. Osteosarcoma is the most frequent bone tumor and is characterized by a high metastatic potential. Chemokine CCL5 (previously called RANTES) has been reported to facilitate tumor progression and metastasis. However, the crosstalk between chemokine CCL5 and vascular endothelial growth factor (VEGF) as well as tumor angiogenesis in human osteosarcoma microenvironment has not been well explored. In this study, we found that CCL5 increased VEGF expression and production in human osteosarcoma cells. The conditioned medium (CM) from CCL5-treated osteosarcoma cells significantly induced tube formation and migration of human endothelial progenitor cells. Pretreatment of cells with CCR5 antibody or transfection with CCR5 specific siRNA blocked CCL5-induced VEGF expression and angiogenesis. CCL5/CCR5 axis demonstrably activated protein kinase C? (PKC?), c-Src, and hypoxia-inducible factor-1 alpha (HIF-1?) signaling cascades to induce VEGF-dependent angiogenesis. Furthermore, knockdown of CCL5 suppressed VEGF expression and attenuated osteosarcoma CM-induced angiogenesis in vitro and in vivo. CCL5 knockdown dramatically abolished tumor growth and angiogenesis in the osteosarcoma xenograft animal model. Importantly, we demonstrated that the expression of CCL5 and VEGF were correlated with tumor stage according the immunohistochemistry analysis of human osteosarcoma tissues. Taken together, our findings provide evidence that CCL5/CCR5 axis promotes VEGF-dependent tumor angiogenesis in human osteosarcoma microenvironment through PKC?/c-Src/HIF-1? signaling pathway. CCL5 may represent a potential therapeutic target against human osteosarcoma.
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Resveratrol suppresses TPA-induced matrix metalloproteinase-9 expression through the inhibition of MAPK pathways in oral cancer cells.
J. Oral Pathol. Med.
PUBLISHED: 10-21-2014
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Naturally occurring agents, such as resveratrol, have been determined to benefit health. Numerous studies have demonstrated that resveratrol has antioxidative, cardioprotective, and neuroprotective properties. However, the effect of resveratrol exerts on the metastasis of oral cancer cells remains unclear. In this study, we investigated the effect the anti-invasive activity of resveratrol on a human oral cancer cell line (SCC-9) in vitro and the underlying mechanisms.
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A survey of ultrasound elastography approaches to percutaneous ablation monitoring.
Proc Inst Mech Eng H
PUBLISHED: 10-20-2014
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Percutaneous thermal ablation has been widely used as a minimally invasive treatment for tumors. Treatment monitoring is essential for preventing complications while ensuring treatment efficacy. Mechanical testing measurements on tissue reveal that tissue stiffness increases with temperature and ablation duration. Different types of imaging methods can be used to monitor ablation procedures, including temperature or thermal strain imaging, strain imaging, modulus imaging, and shear modulus imaging. Ultrasound elastography demonstrates the potential to become the primary imaging modality for monitoring percutaneous ablation. This review briefly presented the state-of-the-art ultrasound elastography approaches for monitoring radiofrequency ablation and microwave ablation. These techniques were divided into four groups: quasi-static elastography, acoustic radiation force elastography, sonoelastography, and applicator motion elastography. Their advantages and limitations were compared and discussed. Future developments were proposed with respect to heat-induced bubbles, tissue inhomogeneities, respiratory motion, three-dimensional monitoring, multi-parametric monitoring, real-time monitoring, experimental data center for percutaneous ablation, and microwave ablation monitoring.
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CCL5 promotes VEGF-dependent angiogenesis by down-regulating miR-200b through PI3K/Akt signaling pathway in human chondrosarcoma cells.
Oncotarget
PUBLISHED: 10-11-2014
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Chondrosarcoma is the second most common primary malignant bone cancer, with potential for local invasion and distant metastasis. Chemokine CCL5 (formerly RANTES) of the CC-chemokine family plays a crucial role in metastasis. Angiogenesis is essential for the cancer metastasis. However, correlation of CCL5 with vascular endothelial growth factor (VEGF) expression and angiogenesis in human chondrosarcoma is still unknown. CCL5-mediated VEGF expression was assessed by qPCR, ELISA, and Western blotting. CCL5-induced angiogenesis was examined by migration and tube formation in endothelial progenitor cells in vitro. CCL5 increased VEGF expression and also promoted chondrosarcoma conditional medium-mediated angiogenesis in vitro and in vivo. Stimulation of chondrosarcoma with CCL5 augmented PI3K and Akt phosphorylation, while PI3K and Akt inhibitor or siRNA abolished CCL5-induced VEGF expression and angiogenesis. We also demonstrated CCL5 inhibiting miR-200b expression and miR-200b mimic reversing the CCL5-enhanced VEGF expression and angiogenesis. Moreover, in chondrosarcoma patients showed the positive correlation between CCL5 and VEGF; negative correlation between CCL5 and miR-200b. Taken together, results demonstrate CCL5 promoting VEGF-dependent angiogenesis in human chondrosarcoma cells by down-regulating miR-200b through PI3K/Akt signaling pathway.
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Osteoblast-derived Wnt-1-induced secreted protein 1 increases VCAM-1 expression and enhances prostate cancer metastasis by down-regulating miR-126.
Oncotarget
PUBLISHED: 10-04-2014
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Bone metastases of prostate cancer (PCa) may cause intractable pain. Wnt-1-induced secreted protein 1 (WISP-1) belongs to the CCN family (CTGF/CYR61/NOV) that plays a key role in bone formation. We found that osteoblast-conditioned medium (OBCM) stimulates migration and vascular adhesion molecule-1 (VCAM)-1 expression in human PCa (PC3 and DU145) cells. Osteoblast transfection with WISP-1 shRNA reduced OBCM-mediated PCa migration and VCAM-1 expression. Stimulation of PCa with OBCM or WISP-1 elevated focal adhesion kinase (FAK) and p38 phosphorylation. Either FAK and p38 inhibitors or siRNA abolished osteoblast-derived WISP-1-induced migration and VCAM-1 expression. Osteoblast-derived WISP-1 inhibited miR-126 expression. Moreover, miR-216 mimic reversed the WISP-1-enhanced migration and VCAM-1 expression. This study suggests that osteoblast-derived WISP-1 promotes migration and VCAM-1 expression in human PCa cells by down-regulating miR-126 expression via ?v?1 integrin, FAK, and p38 signaling pathways. Thus, WISP-1 may be a new molecular therapeutic target in PCa bone metastasis.
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CCN1 induces oncostatin M production in osteoblasts via integrin-dependent signal pathways.
PLoS ONE
PUBLISHED: 09-04-2014
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Inflammatory response and articular destruction are common symptoms of osteoarthritis. Cysteine-rich 61 (CCN1 or Cyr61), a secreted protein from the CCN family, is associated with the extracellular matrix involved in many cellular activities like growth and differentiation. Yet the mechanism of CCN1 interacting with arthritic inflammatory response is unclear. This study finds CCN1 increasing expression of oncostatin m (OSM) in human osteoblastic cells. Pretreatment of ?v?3 monoclonal antibody and inhibitors of focal adhesion kinase (FAK), c-Src, phosphatidylinositol 3-kinase (PI3K), and NF-?B inhibited CCN1-induced OSM expression in osteoblastic cells. Stimulation of cells with CCN1 increased phosphorylation of FAK, c-Src, PI3K, and NF-?B via ?v?3 receptor; CCN1 treatment of osteoblasts increased NF-?B-luciferase activity and p65 binding to NF-?B element on OSM promoter. Results indicate CCN1 heightening OSM expression via ?v?3 receptor, FAK, c-Src, PI3K, and NF-?B signal pathway in osteoblastic cells, suggesting CCN1 as a novel target in arthritis treatment.
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Inhibitory effects of butein on cancer metastasis and bioenergetic modulation.
J. Agric. Food Chem.
PUBLISHED: 09-03-2014
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Tumor metastasis is the major obstacle for cancer treatment. Previous studies have shown that butein exhibits antiangiogenesis property and anticancer effects in different kinds of human cancer cells. However, the effects of butein on metastasis and energy metabolism of cancer cells are mostly unknown. This study showed that butein significantly inhibited invasion of cancer cells without acting in a cytotoxic fashion. It was further demonstrated that butien dramatically suppressed cancer metastasis by an in vivo CAM-intravasation model. Additionally, butein concentration-dependently repressed the expression and activity of matrix metalloproteinase-9 (MMP-9) and urokinase plasminogen activator (uPA). The study indicated that butein may repress MMP-9 and uPA proteolytic activities and subsequently inhibit cancer metastasis via Akt/mTOR/p70S6K translational machinery. Moreover, butein may partly suppress cancer metastasis by down-regulating ATP synthesis via both oxidative and glycolytic metabolism. The results suggest that butein is a potential antimetastatic agent worthy of further development for cancer treatment.
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Supramolecular [60]Fullerene Liquid Crystals Formed By Self-Organized Two-Dimensional Crystals.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-21-2014
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Fullerene-based liquid crystalline materials have both the excellent optical and electrical properties of fullerene and the self-organization and external-field-responsive properties of liquid crystals (LCs). Herein, we demonstrate a new family of thermotropic [60]fullerene supramolecular LCs with hierarchical structures. The [60]fullerene dyads undergo self-organization driven by ?-? interactions to form triple-layer two-dimensional (2D) fullerene crystals sandwiched between layers of alkyl chains. The lamellar packing of 2D crystals gives rise to the formation of supramolecular LCs. This design strategy should be applicable to other molecules and lead to an enlarged family of 2D crystals and supramolecular liquid crystals.
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Brain-derived neurotrophic factor increases vascular endothelial growth factor expression and enhances angiogenesis in human chondrosarcoma cells.
Biochem. Pharmacol.
PUBLISHED: 08-19-2014
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Chondrosarcomas are a type of primary malignant bone cancer, with a potent capacity for local invasion and distant metastasis. Brain-derived neurotrophic factor (BDNF) is commonly upregulated during neurogenesis. The aim of the present study was to examine the mechanism involved in BDNF-mediated vascular endothelial growth factor (VEGF) expression and angiogenesis in human chondrosarcoma cells. Here, we knocked down BDNF expression in chondrosarcoma cells and assessed their capacity to control VEGF expression and angiogenesis in vitro and in vivo. We found knockdown of BDNF decreased VEGF expression and abolished chondrosarcoma conditional medium-mediated angiogenesis in vitro as well as angiogenesis effects in vivo in the chick chorioallantoic membrane and Matrigel plug nude mouse models. In addition, in the xenograft tumor angiogenesis model, the knockdown of BDNF significantly reduced tumor growth and tumor-associated angiogenesis. BDNF increased VEGF expression and angiogenesis through the TrkB receptor, PLC?, PKC?, and the HIF-1? signaling pathway. Finally, we analyzed samples from chondrosarcoma patients by immunohistochemical staining. The expression of BDNF and VEGF protein in 56 chondrosarcoma patients was significantly higher than in normal cartilage. In addition, the high level of BDNF expression correlated strongly with VEGF expression and tumor stage. Taken together, our results indicate that BDNF increases VEGF expression and enhances angiogenesis through a signal transduction pathway that involves the TrkB receptor, PLC?, PKC?, and the HIF-1?. Therefore, BDNF may represent a novel target for anti-angiogenic therapy for human chondrosarcoma.
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Leptin induces oncostatin M production in osteoblasts by downregulating miR-93 through the Akt signaling pathway.
Int J Mol Sci
PUBLISHED: 08-04-2014
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Inflammatory response and articular destruction are common symptoms of osteoarthritis (OA) and rheumatoid arthritis (RA). Leptin, an adipocyte-secreted hormone that centrally regulates weight control, may exert proinflammatory effects in the joint, depending on the immune response. Yet, the mechanism of leptin interacting with the arthritic inflammatory response is unclear. This study finds that leptin increased expression of oncostatin M (OSM) in human osteoblasts in a concentration- and time-dependent manner. In addition, OBRl, but not OBRs receptor antisense oligonucleotide, abolished the leptin-mediated increase of OSM expression. On the other hand, leptin inhibited miR-93 expression; an miR-93 mimic reversed leptin-increased OSM expression. Stimulation of osteoblasts with leptin promoted Akt phosphorylation, while pretreatment of cells with Akt inhibitor or siRNA reversed leptin-inhibited miR-93 expression. Our results showed that leptin heightened OSM expression by downregulating miR-93 through the Akt signaling pathway in osteoblasts, suggesting leptin as a novel target in arthritis treatment.
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Is an observed non-co-linear RNA product spliced in trans, in cis or just in vitro?
Nucleic Acids Res.
PUBLISHED: 07-22-2014
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Global transcriptome investigations often result in the detection of an enormous number of transcripts composed of non-co-linear sequence fragments. Such 'aberrant' transcript products may arise from post-transcriptional events or genetic rearrangements, or may otherwise be false positives (sequencing/alignment errors or in vitro artifacts). Moreover, post-transcriptionally non-co-linear ('PtNcl') transcripts can arise from trans-splicing or back-splicing in cis (to generate so-called 'circular RNA'). Here, we collected previously-predicted human non-co-linear RNA candidates, and designed a validation procedure integrating in silico filters with multiple experimental validation steps to examine their authenticity. We showed that >50% of the tested candidates were in vitro artifacts, even though some had been previously validated by RT-PCR. After excluding the possibility of genetic rearrangements, we distinguished between trans-spliced and circular RNAs, and confirmed that these two splicing forms can share the same non-co-linear junction. Importantly, the experimentally-confirmed PtNcl RNA events and their corresponding PtNcl splicing types (i.e. trans-splicing, circular RNA, or both sharing the same junction) were all expressed in rhesus macaque, and some were even expressed in mouse. Our study thus describes an essential procedure for confirming PtNcl transcripts, and provides further insight into the evolutionary role of PtNcl RNA events, opening up this important, but understudied, class of post-transcriptional events for comprehensive characterization.
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Two-dimensional nanocrystals of molecular Janus particles.
J. Am. Chem. Soc.
PUBLISHED: 07-16-2014
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This paper describes a rational strategy to obtain self-assembled two-dimensional (2D) nanocrystals with definite and uniform thickness from a series of molecular Janus particles based on molecular nanoparticles (MNPs). MNPs are 3D framework with rigid shapes. Three different types of MNPs based on derivatives of polyhedral oligomeric silsesquioxane (POSS), [60]fullerene (C60), and Lindqvist-type polyoxometalate (POM) are used as building blocks to construct these amphiphilic molecular Janus particles by covalently connecting hydrophobic crystalline BPOSS with a charged hydrophilic MNP. The formation of 2D nanocrystals with an exact thickness of double layers of molecules is driven by directional crystallization of the BPOSS MNP and controlled by various factors such as solvent polarity, number of counterions, and sizes of the MNPs. Strong solvating interactions of the ionic MNPs in polar solvents (e.g., acetonitrile and dimethylformamide) are crucial to provide repulsive interactions between the charged outlying ionic MNPs and suppress further aggregation along the layer normal direction. The number of counterions per molecule plays a major role in determining the self-assembled morphologies. Size matching of the hydrophobic and ionic MNPs is another critical factor in the formation of 2D nanocrystals. Self-assembly of rationally designed molecular Janus particles provides a unique "bottom-up" strategy to engineer 2D nanostructures.
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The Characteristics of Thrombin in Osteoarthritic Pathogenesis and Treatment.
Biomed Res Int
PUBLISHED: 07-09-2014
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Osteoarthritis (OA) is a mechanical abnormality associated with degradation of joints. It is characterized by chronic, progressive degeneration of articular cartilage, abnormalities of bone, and synovial change. The most common symptom of OA is local inflammation resulting from exogenous stress or endogenous abnormal cytokines. Additionally, OA is associated with local and/or systemic activation of coagulation and anticoagulation pathways. Thrombin plays an important role in the stimulation of fibrin deposition and the proinflammatory processes in OA. Thrombin mediates hemostatic and inflammatory responses and guides the immune response to tissue damage. Thrombin activates intracellular signaling pathways by interacting with transmembrane domain G protein coupled receptors (GPCRs), known as protease-activated receptors (PARs). In pathogenic mechanisms, PARs have been implicated in the development of acute and chronic inflammatory responses in OA. Therefore, discovery of thrombin signaling pathways would help us to understand the mechanism of OA pathogenesis and lead us to develop therapeutic drugs in the future.
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CTGF increases matrix metalloproteinases expression and subsequently promotes tumor metastasis in human osteosarcoma through down-regulating miR-519d.
Oncotarget
PUBLISHED: 07-09-2014
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Osteosarcoma, the most common primary malignant bone tumor, shows potent capacity for local invasion and distant metastasis. Connective tissue growth factor (CTGF/CCN2), a secreted protein, binds to integrins, modulates invasive behavior of certain human cancer cells. Effect of CTGF in metastasis of human osteosarcoma is unknown. We found overexpression of CTGF increasing matrix metalloproteinases (MMPs)-2 and MMP-3 expression as well as promoting cell migration. MicroRNA (miRNA) analysis of CTGF-overexpressed osteosarcoma versus control cells probed mechanisms of CTGF-mediated promotion of migration. Among miRNAs regulated by CTGF, miR-519d was most downregulated after CTGF treatment. Co-transfection with miR-519d mimic reversed CTGF-mediated MMPs expression and cell migration. Also, MEK and ERK inhibitors or mutants reduced CTGF-increased cell migration and miR-519d suppression. By contrast, knockdown of CTGF diminished lung metastasis in vivo. Clinical samples indicate CTGF expression as linked with clinical stage and tumor metastasis. Taken together, data show CTGF elevating MMPs expression and subsequently promoting tumor metastasis in human osteosarcoma, down-regulating miR-519d via MEK and ERK pathways, making CTGF a new molecular therapeutic target in osteosarcoma metastasis.
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Ectopic DNMT3L triggers assembly of a repressive complex for retroviral silencing in somatic cells.
J. Virol.
PUBLISHED: 07-02-2014
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Mammalian genomes are replete with retrotransposable elements, including endogenous retroviruses. DNA methyltransferase 3-like (DNMT3L) is an epigenetic regulator expressed in prospermatogonia, growing oocytes, and embryonic stem (ES) cells. Here, we demonstrate that DNMT3L enhances the interaction of repressive epigenetic modifiers, including histone deacetylase 1 (HDAC1), SET domain, bifurcated 1 (SETDB1), DNA methyltransferase 3A (DNMT3A), and tripartite motif-containing protein 28 (TRIM28; also known as TIF1? and KAP1) in ES cells and orchestrates retroviral silencing activity with TRIM28 through mechanisms including, but not limited to, de novo DNA methylation. Ectopic expression of DNMT3L in somatic cells causes methylation-independent retroviral silencing activity by recruitment of the TRIM28/HDAC1/SETDB1/DNMT3A/DNMT3L complex to newly integrated Moloney murine leukemia virus (Mo-MuLV) proviral DNA. Concurrent with this recruitment, we also observed the accumulation of histone H3 lysine 9 trimethylation (H3K9me3) and heterochromatin protein 1 gamma (HP1?), as well as reduced H3K9 and H3K27 acetylation at Mo-MuLV proviral sequences. Ectopic expression of DNMT3L in late-passage mouse embryonic fibroblasts (MEFs) recruited cytoplasmically localized HDAC1 to the nucleus. The formation of this epigenetic modifying complex requires interaction of DNMT3L with DNMT3A as well as with histone H3. In fetal testes at embryonic day 17.5, endogenous DNMT3L also enhanced the binding among TRIM28, DNMT3A, SETDB1, and HDAC1. We propose that DNMT3L may be involved in initiating a cascade of repressive epigenetic modifications by assisting in the preparation of a chromatin context that further attracts DNMT3A-DNMT3L binding and installs longer-term DNA methylation marks at newly integrated retroviruses.
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Readiness to quit as a predictor for outcomes of smoking-reduction programme with transdermal nicotine patch or bupropion in a sample of 308 patients with schizophrenia.
Eur Arch Psychiatry Clin Neurosci
PUBLISHED: 06-28-2014
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Readiness to quit has been found to predict smoking-cessation outcomes in a general population. However, little is known about the relationship between the readiness to quit and smoking-reduction outcomes in patients with schizophrenia treated with pharmacological adjuvants. The aim of this study was to examine the association between readiness to quit and smoking-reduction outcomes in patients with schizophrenia. A total of 308 subjects using nicotine replacement therapy (NRT) (N = 242) or bupropion (N = 66) participated in an 8-week smoking-reduction programme. Participants were categorised into precontemplators (N = 127), contemplators (N = 76) and preparators (N = 105) to quit smoking based on the transtheoretical model. There was a significant difference in change in number of cigarettes (NOC) (p = 0.007) and Fagerstrom test for nicotine dependence (FTND) score (nicotine dependence level) (p = 0.029) across the stages of change. A linear regression model revealed trend of increasing reduction in NOC and FTND scores in different stages of change (NOC: B = -1.22, t = -2.81, p = 0.005; FTND: B = -0.43, t = -2.57, p = 0.011). However, the 7-day point prevalence of abstinence was 5.5 % (18/308), but there was no significant association between stage of change and smoking cessation (p = 0.26), possibly due to a very small sample size of successful quitters. In summary, among a cohort of institutionalised chronic schizophrenia patients receiving 8-week NRT or bupropion, stage of change can predict smoking reduction and may serve as a useful indicator for patients' preparedness before a trial of smoking reduction.
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Association of increased travel distance to dialysis units with the risk of anemia in rural chronic hemodialysis elderly.
Hemodial Int
PUBLISHED: 06-14-2014
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Geographic remoteness has been found to influence health-related outcomes negatively. As reported in the literature, rural dialysis patients have a higher risk of mortality with increasing travel distance to dialysis units. However, few studies have focused on the impact of travel distances on the development of dialysis complications. We utilized a prospectively collected chronic hemodialysis patient cohort from a rural regional hospital for analysis. Data on demographics, comorbidities, and serum laboratory results were obtained. Correlation analyses between travel distance to dialysis units and dialysis complications were conducted, and significantly correlated parameters were entered into multivariate logistic regression models to determine their exact associations. A total of 46 rural chronic hemodialysis patients were enrolled, with an average age higher than others in the literature. Significant correlation was found between travel distance and serum hemoglobin levels (R(2) ?=?-0.34, P value?=?0.029). Multivariate logistic regression found that every 1?km increase in travel distance was associated with an increased risk of anemia (hemoglobin <9?g/dL) (odds ratio 1.46; P value?=?0.01). Sensitivity analyses further showed that the associated risk was partially attenuated by serum albumin (odds ratio 1.83; P value?=?0.07) and ferritin (odds ratio 1.39; P value?=?0.08) levels. This is the first study to demonstrate the association between increased travel distance to dialysis units and the risk of anemia in chronic dialysis patients, especially elderly. Malnutrition, inflammation, and atherosclerosis syndrome could be partially responsible for the observed association. Further research is required to confirm our findings.
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Cognitive inference device for activity supervision in the elderly.
ScientificWorldJournal
PUBLISHED: 06-10-2014
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Human activity, life span, and quality of life are enhanced by innovations in science and technology. Aging individual needs to take advantage of these developments to lead a self-regulated life. However, maintaining a self-regulated life at old age involves a high degree of risk, and the elderly often fail at this goal. Thus, the objective of our study is to investigate the feasibility of implementing a cognitive inference device (CI-device) for effective activity supervision in the elderly. To frame the CI-device, we propose a device design framework along with an inference algorithm and implement the designs through an artificial neural model with different configurations, mapping the CI-device's functions to minimise the device's prediction error. An analysis and discussion are then provided to validate the feasibility of CI-device implementation for activity supervision in the elderly.
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Leptin increases VEGF expression and enhances angiogenesis in human chondrosarcoma cells.
Biochim. Biophys. Acta
PUBLISHED: 06-03-2014
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Leptin, 16kDa product of obese gene, is adipocytokine playing critical role in regulation of body weight. In recent years, leptin is also defined as potent angiogenic factor involving in tumorigenesis, angiogenesis, and metastasis. However, it is unknown whether leptin regulates VEGF production in human chondrosarcoma and contributing the tumor-associated angiogenesis.
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Evaluation of endoscopic salpingectomy for sterilization of female Formosan macaques (Macaca cyclopis).
Am. J. Primatol.
PUBLISHED: 05-16-2014
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We evaluated the safety and postsurgical outcomes of endoscopic salpingectomy for sterilization of female Formosan macaques (Macaca cyclopis) as a method of population control. Nineteen adult female Formosan macaques were included in our study. The fallopian tubes of each anesthetized macaque were cauterized and excised endoscopically using a 2.7-mm rigid endoscope system. We recorded the complications encountered, and objectively scored the amount of hemorrhage throughout the procedure. Postoperative ovarian function was evaluated by monitoring the serum levels of sex hormones in ten of the macaques for two ovarian cycles following the salpingectomy. Two to 13 months later, eight of the 19 macaques underwent laparoscopy for the objective evaluation of inflammation at the surgical sites on the fallopian tubes. No major anesthetic- or surgical-associated complications were observed in any of the macaques. The hormonal evaluation showed cyclic ovarian function after salpingectomy in all of the ten macaques examined, and the parameters were comparable to those of other macaque species. The long-term postoperative level of inflammation at the surgical site was minimal to low, and was lower than that reported for other tubal occlusion techniques used in macaques. The use of a 2.7-mm rigid endoscope for salpingectomy in macaques is safe and efficient, with fewer postoperative complications than comparable sterilization techniques. Am. J. Primatol. © 2014 Wiley Periodicals, Inc.
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Granulosa cells and retinoic acid co-treatment enrich potential germ cells from manually selected Oct4-EGFP expressing human embryonic stem cells.
Reprod. Biomed. Online
PUBLISHED: 05-13-2014
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Differentiation of human embryonic stem (HES) cells to germ cells may become clinically useful in overcoming diseases related to germ-cell development. Niches were used to differentiate HES cell lines, NTU1 and H9 Oct4-enhanced green fluorescence protein (EGFP), including laminin, granulosa cell co-culture or conditioned medium, ovarian stromal cell co-culture or conditioned medium, retinoic acid, stem cell factor (SCF) and BMP4-BMP7-BMP8b treatment. Flow cytometry showed that granulosa cell co-culture (P < 0.001) or conditioned medium (P = 0.007) treatment for 14 days significantly increased the percentages of differentiated H9 Oct4-EGFP cells expressing early germ cell marker stage-specific embryonic antigen 1(SSEA1); sorted SSEA1[+] cells did not express higher levels of germ cell gene VASA and GDF9. Manually collected H9 Oct4-EGFP[+] cells expressed significantly higher levels of VASA (P = 0.005) and GDF9 (P = 0.001). H9 Oct4-EGFP[+] cells developed to ovarian follicle-like structures after culture for 28 days but with low efficiency. Unlike SCF and BMP4, retinoic acid co-treatment enhanced VASA, GDF9 and SCP3 expression. A protocol is recommended to enrich differentiated HES cells with germ-cell potential by culture with granulosa cells, conditioned medium or retinoic acid, manual selection of Oct4-EGFP[+] cells, and analysis of VASA, GDF9 expression, or both.
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Diagnostic performance of random urine samples using albumin concentration vs ratio of albumin to creatinine for microalbuminuria screening in patients with diabetes mellitus: a systematic review and meta-analysis.
JAMA Intern Med
PUBLISHED: 05-07-2014
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A random urine sample measuring the albumin concentration (UAC) without simultaneously measuring the urinary creatinine is less expensive than measuring the ratio of albumin to creatinine (ACR), but comparisons of their diagnostic performance for microalbuminuria screening among patients with diabetes mellitus (DM) have not been undertaken in previous meta-analyses.
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Naringin suppress chondrosarcoma migration through inhibition vascular adhesion molecule-1 expression by modulating miR-126.
Int. Immunopharmacol.
PUBLISHED: 04-30-2014
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Chondrosarcoma, a primary malignant bone cancer, has a potent capacity to invade locally and cause distant metastasis, especially to the lungs. Patients diagnosed with it have poor prognosis. Naringin, polymethoxylated flavonoid commonly found in citrus fruits, has anti-oxidant, anti-inflammatory and anti-tumor activity; whether naringin regulates migration of chondrosarcoma is largely unknown. Here we report that naringin does not expedite apoptosis in human chondrosarcoma. By contrast, at noncytotoxic concentrations, naringin suppressed migration and invasion of chondrosarcoma cells. Vascular cell adhesion molecule-1 (VCAM-1) of the immunoglobulin superfamily is linked with metastasis; we found incubation of chondrosarcoma cells with naringin reducing mRNA transcription for, and cell surface expression of, VCAM-1. We also observed that naringin enhancing miR-126 expression, and miR-126 inhibitor reversed the naringin-inhibited cell motility and VCAM-1 expression. Therefore, naringin inhibits migration and invasion of human chondrosarcoma via down-regulation of VCAM-1 by increasing miR-126. Thus, naringin may be a novel anti-migration agent for the treatment of migration in chondrosarcoma.
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Semi-automatic breast ultrasound image segmentation based on mean shift and graph cuts.
Ultrason Imaging
PUBLISHED: 04-22-2014
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Computerized tumor segmentation on breast ultrasound (BUS) images remains a challenging task. In this paper, we proposed a new method for semi-automatic tumor segmentation on BUS images using Gaussian filtering, histogram equalization, mean shift, and graph cuts. The only interaction required was to select two diagonal points to determine a region of interest (ROI) on an input image. The ROI image was shrunken by a factor of 2 using bicubic interpolation to reduce computation time. The shrunken image was smoothed by a Gaussian filter and then contrast-enhanced by histogram equalization. Next, the enhanced image was filtered by pyramid mean shift to improve homogeneity. The object and background seeds for graph cuts were automatically generated on the filtered image. Using these seeds, the filtered image was then segmented by graph cuts into a binary image containing the object and background. Finally, the binary image was expanded by a factor of 2 using bicubic interpolation, and the expanded image was processed by morphological opening and closing to refine the tumor contour. The method was implemented with OpenCV 2.4.3 and Visual Studio 2010 and tested for 38 BUS images with benign tumors and 31 BUS images with malignant tumors from different ultrasound scanners. Experimental results showed that our method had a true positive rate (TP) of 91.7%, a false positive (FP) rate of 11.9%, and a similarity (SI) rate of 85.6%. The mean run time on Intel Core 2.66 GHz CPU and 4 GB RAM was 0.49 ± 0.36 s. The experimental results indicate that the proposed method may be useful in BUS image segmentation.
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Paeonol suppresses chondrosarcoma metastasis through up-regulation of miR-141 by modulating PKC? and c-Src signaling pathway.
Int J Mol Sci
PUBLISHED: 04-16-2014
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Chondrosarcoma, a primary malignant bone cancer, has potential for local invasion and distant metastasis, especially to the lungs. Patients diagnosed with it show poor prognosis. Paeonol (2'-hydroxy-4'-methoxyacetophenone), the main active compound of traditional Chinese remedy Paeonia lactiflora Pallas, exhibits anti-inflammatory and anti-tumor activity; whether paeonol regulates metastatic chondrosarcoma is largely unknown. Here, we find paeonol do not increase apoptosis. By contrast, at non-cytotoxic concentrations, paeonol suppresses migration and invasion of chondrosarcoma cells. We also demonstrate paeonol enhancing miR-141 expression and miR-141 inhibitor reversing paeonol-inhibited cell motility; paeonol also reduces protein kinase C (PKC)d and c-Src kinase activity. Since paeonol inhibits migration and invasion of human chondrosarcoma via up-regulation of miR-141 via PKCd and c-Src pathways, it thus might be a novel anti-metastasis agent for treatment of metastatic chondrosarcoma.
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Prostate cancer-derived CCN3 induces M2 macrophage infiltration and contributes to angiogenesis in prostate cancer microenvironment.
Oncotarget
PUBLISHED: 04-12-2014
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Tumor-associated macrophages (TAMs) are M2-polarized macrophages that infiltrate the tumor microenvironment and promote tumorigenesis. However, the mechanisms by which TAMs modulate prostate cancer (PCa) growth are poorly understood. Here, we found that expression of Nephroblastoma Overexpressed (NOV/CCN3) is upregulated in PCa cells and correlated with M2 macrophage infiltration. RAW264.7 macrophage migration was induced by conditioned media (CM) from various PCa cells in proportion to the cellular level of CCN3 expression and was inhibited by an anti-CCN3 neutralizing antibody. CCN3 and PCaCM treatment skewed RAW264.7 cell differentiation from an M1 phenotype to an M2 phenotype. PCa-derived CCN3 induced focal adhesion kinase (FAK)/Akt/NF-?B signaling in RAW264.7 cells, which resulted in VEGF expression and subsequently increased tube formation in endothelial progenitor cells. Finally, PCa-secreted CCN3 stimulated RAW264.7 cells and promoted angiogenesis in the chick chorioallantoic membrane assay (CAM), and increased tumor growth and tumor-associated angiogenesis in a PCa xenograft mouse model. Our results indicate that PCa-secreted CCN3 can recruit macrophages and skew their differentiation to an M2 phenotype. In turn, CCN3-stimulated macrophages contribute to VEGF-dependent angiogenesis. This study reveals a novel mechanism by which TAMs enhance PCa angiogenesis and identifies a potential therapeutic target for PCa.
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Inhibition of soluble tumor necrosis factor is therapeutic in Huntington's disease.
Hum. Mol. Genet.
PUBLISHED: 04-03-2014
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Neuroinflammation is a common feature of many neurodegenerative diseases, including Huntington's disease (HD). HD is an autosomal dominant genetic disease caused by an expanded CAG repeat in exon 1 of the huntingtin (HTT) gene. Previous studies demonstrated that levels of several proinflammatory cytokines, including tumor necrosis factor (TNF)-?, were higher in the plasma and brain tissues of mice and patients with HD, suggesting that inflammation may contribute to HD progression. To evaluate the pathological role of TNF-? in HD pathogenesis, we blocked TNF-? signaling using a dominant negative inhibitor of soluble TNF-? (XPro1595). XPro1595 effectively suppressed the inflammatory responses of primary astrocytes-enriched culture isolated from a transgenic mouse model (R6/2) and human astrocytes-enriched culture derived from induced pluripotent stem cells (iPSCs) of HD patients evoked by lipopolysaccharide and cytokines, respectively. Moreover, XPro1595 protected the cytokine-induced toxicity of primary R6/2 neurons and human neurons derived from iPSCs of HD patients. To assess the beneficial effect of XPro1595 in vivo, an intracerebroventricular (i.c.v.) infusion was provided with an osmotic minipump. ELISA analyses showed that i.c.v. infusion of XPro1595 decreased elevated levels of TNF? in the cortex and striatum, improved motor function, reduced caspase activation, diminished the amount of mutant HTT aggregates, increased neuronal density and decreased gliosis in brains of R6/2 mice. Moreover, reducing the peripheral inflammatory response by a systemic injection of XPro1595 improved the impaired motor function of R6/2 mice but did not affect caspase activation. Collectively, our findings suggest that an effective and selective anti-inflammatory treatment targeting the abnormal brain inflammatory response is a potential therapeutic strategy for HD.
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Systemic inflammation in xenograft recipients precedes activation of coagulation.
Xenotransplantation
PUBLISHED: 03-28-2014
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Dysregulation of coagulation is considered a major barrier against successful pig organ xenotransplantation in non-human primates. Inflammation is known to promote activation of coagulation. The role of pro-inflammatory factors as well as the relationship between inflammation and activation of coagulation in xenograft recipients is poorly understood.
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Design and experimental evaluation of a 256-channel dual-frequency ultrasound phased-array system for transcranial blood-brain barrier opening and brain drug delivery.
IEEE Trans Biomed Eng
PUBLISHED: 03-25-2014
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Focused ultrasound (FUS) in the presence of microbubbles can bring about transcranial and local opening of the blood-brain barrier (BBB) for potential noninvasive delivery of drugs to the brain. A phased-array ultrasound system is essential for FUS-BBB opening to enable electronic steering and correction of the focal beam which is distorted by cranial bone. Here, we demonstrate our prototype design of a 256-channel ultrasound phased-array system for large-region transcranial BBB opening in the brains of large animals. One of the unique features of this system is the capability of generating concurrent dual-frequency ultrasound signals from the driving system for potential enhancement of BBB opening. A wide range of signal frequencies can be generated (frequency = 0.2-1.2 MHz) with controllable driving burst patterns. Precise output power can be controlled for individual channels via 8-bit duty-cycle control of transistor-transistor logic signals and the 8-bit microcontroller-controlled buck converter power supply output voltage. The prototype system was found to be in compliance with the electromagnetic compatibility standard. Moreover, large animal experiments confirmed the phase switching effectiveness of this system, and induction of either a precise spot or large region of BBB opening through fast focal-beam switching. We also demonstrated the capability of dual-frequency exposure to potentially enhance the BBB-opening effect. This study contributes to the design of ultrasound phased arrays for future clinical applications, and provides a new direction toward optimizing FUS brain drug delivery.
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Self-assembly of fullerene-based janus particles in solution: effects of molecular architecture and solvent.
Chemistry
PUBLISHED: 03-20-2014
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Two molecular Janus particles based on amphiphilic [60]fullerene (C60 ) derivatives were designed and synthesized by using the regioselective Bingel-Hirsh reaction and the click reaction. These particles contain carboxylic acid functional groups, a hydrophilic fullerene (AC60 ), and a hydrophobic C60 in different ratios and have distinct molecular architectures: 1:1 (AC60 -C60 ) and 1:2 (AC60 -2C60 ). These molecular Janus particles can self-assemble in solution to form aggregates with various types of micellar morphology. Whereas vesicular morphology was observed for both AC60 -C60 and AC60 -2C60 in tetrahydrofuran, in a mixture of N,N-dimethylformamide (DMF)/water, spherical micelles and cylindrical micelles were observed for AC60 -C60 and AC60 -2C60 , respectively. A mechanism of formation was tentatively proposed based on the effects of molecular architecture and solvent polarity on self-assembly.
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Suppression of the SOX2 neural effector gene by PRDM1 promotes human germ cell fate in embryonic stem cells.
Stem Cell Reports
PUBLISHED: 02-11-2014
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The mechanisms of transcriptional regulation underlying human primordial germ cell (PGC) differentiation are largely unknown. The transcriptional repressor Prdm1/Blimp-1 is known to play a critical role in controlling germ cell specification in mice. Here, we show that PRDM1 is expressed in developing human gonads and contributes to the determination of germline versus neural fate in early development. We show that knockdown of PRDM1 in human embryonic stem cells (hESCs) impairs germline potential and upregulates neural genes. Conversely, ectopic expression of PRDM1 in hESCs promotes the generation of cells that exhibit phenotypic and transcriptomic features of early PGCs. Furthermore, PRDM1 suppresses transcription of SOX2. Overexpression of SOX2 in hESCs under conditions favoring germline differentiation skews cell fate from the germline to the neural lineage. Collectively, our results demonstrate that PRDM1 serves as a molecular switch to modulate the divergence of neural or germline fates through repression of SOX2 during human development.
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Angiopoietin-2-induced arterial stiffness in CKD.
J. Am. Soc. Nephrol.
PUBLISHED: 02-07-2014
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The mechanism of vascular calcification in CKD is not understood fully, but may involve collagen deposition in the arterial wall upon osteo/chondrocytic transformation of vascular smooth muscle cells (VSMCs). Increased levels of circulating angiopoietin-2 correlate with markers of CKD progression and angiopoietin-2 regulate inflammatory responses, including intercellular and vascular adhesion and recruitment of VSMCs. Here, we investigate the potential role of angiopoietin-2 in the pathogenesis of arterial stiffness associated with CKD. In a cohort of 416 patients with CKD, the plasma level of angiopoietin-2 correlated independently with the severity of arterial stiffness assessed by pulse wave velocity. In mice subjected to 5/6 subtotal nephrectomy or unilateral ureteral obstruction, plasma levels of angiopoietin-2 also increased. Angiopoietin-2 expression markedly increased in tubular epithelial cells of fibrotic kidneys but decreased in other tissues, including aorta and lung, after 5/6 subtotal nephrectomy. Expression of collagen and profibrotic genes in aortic VSMCs increased in mice after 5/6 subtotal nephrectomy and in mice producing human angiopoietin-2. Angiopoietin-2 stimulated endothelial expression of chemokines and adhesion molecules for monocytes, increased Ly6C(low) macrophages in aorta, and increased the expression of the profibrotic cytokine TGF-?1 in aortic endothelial cells and Ly6C(low) macrophages. Angiopoietin-2 blockade attenuated expression of monocyte chemokines, profibrotic cytokines, and collagen in aorta of mice after 5/6 subtotal nephrectomy. This study identifies angiopoietin-2 as a link between kidney fibrosis and arterial stiffness. Targeting angiopoietin-2 to attenuate inflammation and collagen expression may provide a novel therapy for cardiovascular disease in CKD.
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VIRIDANS STREPTOCOCCI IN PERITONEAL DIALYSIS PERITONITIS: CLINICAL COURSES AND LONG-TERM OUTCOMES.
Perit Dial Int
PUBLISHED: 02-06-2014
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The clinical courses and long-term outcomes of viridans streptococcus (VS) peritoneal dialysis (PD) peritonitis remain unclear.
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Quercetin attenuates renal ischemia/reperfusion injury via an activation of AMP-activated protein kinase-regulated autophagy pathway.
J. Nutr. Biochem.
PUBLISHED: 01-27-2014
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Renal ischemia/reperfusion (I/R) is a major cause of acute renal failure. Quercetin, a flavonoid antioxidant, presents in many kinds of food. The molecular mechanism of quercetin on renal protection during I/R is still unclear. Here, we investigated the role of AMP-activated protein kinase (AMPK)-regulated autophagy in renal protection by quercetin. To investigate whether quercetin protects renal cells from I/R-induced cell injury, an in vitro model of I/R and an in vivo I/R model were used. Cell apoptosis was determined by propidium iodide/annexin V staining. Western blotting and immunofluorescence were used to determine the autophagy. AMPK expression was inhibited with appropriate short hairpin RNA (shRNA). In cultured renal tubular cell I/R model, quercetin decreased the cell injury, up-regulated the AMPK phosphorylation, down-regulated the mammalian target of rapamycin (mTOR) phosphorylation and activated autophagy during I/R. Knockdown of AMPK by shRNA transfection decreased the quercetin-induced autophagy but did not affect the mTOR phosphorylation. In I/R mouse model, quercetin decreased the increased serum creatinine level and altered renal histological score. Quercetin also increased AMPK phosphorylation, inhibited the mTOR phosphorylation and activated autophagy in the kidneys of I/R mice. These results suggest that quercetin activates an AMPK-regulated autophagy signaling pathway, which offers a protective effect in renal I/R injury.
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BMP-7 Enhances Cell Migration and ?v?3 Integrin Expression via a c-Src-Dependent Pathway in Human Chondrosarcoma Cells.
PLoS ONE
PUBLISHED: 01-01-2014
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Bone morphogenic protein (BMP)-7 is a member of the transforming growth factor (TGF)-beta superfamily, which is originally identified based on its ability to induce cartilage and bone formation. In recent years, BMP-7 is also defined as a potent promoter of cell motility, invasion, and metastasis. However, there is little knowledge of the role of BMP-7 and its cellular function in chondrosarcoma cells. In the present study, we investigated the biological impact of BMP-7 on cell motility using transwell assay. In addition, the intracellular signaling pathways were also investigated by pharmacological and genetic approaches. Our results demonstrated that treatment with exogenous BMP-7 markedly increased cell migration by activating c-Src/PI3K/Akt/IKK/NF-?B signaling pathway, resulting in the transactivation of ?v?3 integrin expression. Indeed, abrogation of signaling activation, by chemical inhibition or expression of a kinase dead form of the protein attenuated BMP-7-induced expression of integrin ?v?3 and cell migration. These findings may provide a useful tool for diagnostic/prognostic purposes and even therapeutically in late-stage chondrosarcoma as an anti-metastatic agent.
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Acinetobacter Peritoneal Dialysis Peritonitis: A Changing Landscape over Time.
PLoS ONE
PUBLISHED: 01-01-2014
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Acinetobacter species are assuming an increasingly important role in modern medicine, with their persistent presence in health-care settings and antibiotic resistance. However, clinical reports addressing this issue in patients with peritoneal dialysis (PD) peritonitis are rare.
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Serum myostatin is reduced in individuals with metabolic syndrome.
PLoS ONE
PUBLISHED: 01-01-2014
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Myostatin is a negative regulator of skeletal muscle mass and may also modulate energy metabolism secondarily. We aim to investigate the relationship between serum myostatin and the metabolic variables in diabetic (DM) and non-diabetic subjects.
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5-Lipoxygenase inhibitors attenuate TNF-?-induced inflammation in human synovial fibroblasts.
PLoS ONE
PUBLISHED: 01-01-2014
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The lipoxygenase isoform of 5-lipoxygenase (5-LOX) is reported to be overexpressed in human rheumatoid arthritis synovial tissue and involved in the progress of inflammatory arthritis. However, the detailed mechanism of how 5-lipoxygenase regulates the inflammatory response in arthritis synovial tissue is still unclear. The aim of this study was to investigate the involvement of lipoxygenase pathways in TNF-?-induced production of cytokines and chemokines. Human synovial fibroblasts from rheumatoid patients were used in this study. 5-LOX inhibitors and shRNA were used to examine the involvement of 5-LOX in TNF-?-induced cytokines and chemokines expression. The signaling pathways were examined by Western Blotting or immunofluorescence staining. The effect of 5-LOX inhibitor on TNF-?-induced chemokine expression and paw edema was also explored in vivo in C57BL/6 mice. Treatment with 5-LOX inhibitors significantly decreased TNF-?-induced pro-inflammatory mediators including interleukin-6 (IL-6) and monocyte chemo-attractant protein-1 (MCP-1) in human synovial fibroblasts. Knockdown of 5-LOX using shRNA exerted similar inhibitory effects. The abrogation of NF-?B activation was involved in the antagonizing effects of these inhibitors. Furthermore, 5-LOX inhibitor decreased TNF-?-induced up-regulation of serum MCP-1 level and paw edema in mouse model. Our results provide the evidence that the administration of 5-LOX inhibitors is able to ameliorate TNF-?-induced cytokine/chemokine release and paw edema, indicating that 5-LOX inhibitors may be developed for therapeutic treatment of inflammatory arthritis.
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A nationwide survey of mild cognitive impairment and dementia, including very mild dementia, in Taiwan.
PLoS ONE
PUBLISHED: 01-01-2014
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An increasing population of dementia patients produces substantial societal impacts. We assessed the prevalence of mild cognitive impairment (MCI) and all-cause dementia, including very mild dementia (VMD), in Taiwan. In a nationwide population-based cross-sectional survey, participants were selected by computerized random sampling from all 19 Taiwan counties and were enrolled between December 2011 and March 2013. Cases were identified through in-person interviews based on the National Institute on Aging-Alzheimer's Association clinical criteria. Demographic data and histories involving mental status and function in daily living were collected. The principal objective assessments were the Taiwanese Mental Status Examination and Clinical Dementia Rating. In all, 10,432 people aged 65 years or older (mean age 76.2 ± 6.7, 52.3% women) were interviewed. The age-adjusted prevalence of all-cause dementia was 8.04% (95% CI 7.47-8.61), including a 3.25% (95% CI 2.89-3.61) prevalence of VMD; that of MCI was 18.76% (95% CI 17.91-19.61). Women had a higher prevalence than men of both all-cause dementia (9.71% vs. 6.36%) and MCI (21.63% vs. 15.57%). MCI affects a considerable portion of the population aged 65 and above in Taiwan. The inclusion of VMD yields dementia prevalence rates higher than those previously reported from Taiwan. Old age, female gender, and a low educational level are significant associated factors.
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Entropic imaging of cataract lens: an in vitro study.
PLoS ONE
PUBLISHED: 01-01-2014
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Phacoemulsification is a common surgical method for treating advanced cataracts. Determining the optimal phacoemulsification energy depends on the hardness of the lens involved. Previous studies have shown that it is possible to evaluate lens hardness via ultrasound parametric imaging based on statistical models that require data to follow a specific distribution. To make the method more system-adaptive, nonmodel-based imaging approach may be necessary in the visualization of lens hardness. This study investigated the feasibility of applying an information theory derived parameter - Shannon entropy from ultrasound backscatter to quantify lens hardness. To determine the physical significance of entropy, we performed computer simulations to investigate the relationship between the signal-to-noise ratio (SNR) based on the Rayleigh distribution and Shannon entropy. Young's modulus was measured in porcine lenses, in which cataracts had been artificially induced by the immersion in formalin solution in vitro. A 35-MHz ultrasound transducer was used to scan the cataract lenses for entropy imaging. The results showed that the entropy is 4.8 when the backscatter data form a Rayleigh distribution corresponding to an SNR of 1.91. The Young's modulus of the lens increased from approximately 8 to 100 kPa when we increased the immersion time from 40 to 160 min (correlation coefficient r?=?0.99). Furthermore, the results indicated that entropy imaging seemed to facilitate visualizing different degrees of lens hardening. The mean entropy value increased from 2.7 to 4.0 as the Young's modulus increased from 8 to 100 kPa (r?=?0.85), suggesting that entropy imaging may have greater potential than that of conventional statistical parametric imaging in determining the optimal energy to apply during phacoemulsification.
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An association of genotypes and antimicrobial resistance patterns among Salmonella isolates from pigs and humans in Taiwan.
PLoS ONE
PUBLISHED: 01-01-2014
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We collected 110 Salmonella enterica isolates from sick pigs and determined their serotypes, genotypes using pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibility to 12 antimicrobials and compared the data with a collection of 18,280 isolates obtained from humans. The pig isolates fell into 12 common serovars for human salmonellosis in Taiwan; S. Typhimurium, S. Choleraesuis, S. Derby, S. Livingstone, and S. Schwarzengrund were the 5 most common serovars and accounted for a total of 84% of the collection. Of the 110 isolates, 106 (96%) were multidrug resistant (MDR) and 48 (44%) had PFGE patterns found in human isolates. S. Typhimurium, S. Choleraesuis, and S. Schwarzengrund were among the most highly resistant serovars. The majority of the 3 serovars were resistant to 8-11 of the tested antimicrobials. The isolates from pigs and humans sharing a common PFGE pattern displayed identical or very similar resistance patterns and Salmonella strains that caused severe infection in pigs were also capable of causing infections in humans. The results indicate that pigs are one of the major reservoirs to human salmonellosis in Taiwan. Almost all of the pig isolates were MDR, which highlights the necessity of strictly regulating the use of antimicrobials in the agriculture sector in Taiwan.
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Vitamin D and the Immune System from the Nephrologist's Viewpoint.
ISRN Endocrinol
PUBLISHED: 01-01-2014
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Vitamin D and its analogues are widely used as treatments by clinical nephrologists, especially when treating chronic kidney disease (CKD) patients with secondary hyperparathyroidism. As CKD progresses, the ability to compensate for elevations in parathyroid hormone (PTH) and fibroblast growth factor-23 and for decreases in 1,25(OH)2D3 becomes inadequate, which results in hyperphosphatemia, abnormal bone disorders, and extra-skeletal calcification. In addition to its calciotropic effect on the regulation of calcium, phosphate, and parathyroid hormone, vitamin D has many other noncalciotropic effects, including controlling cell differentiation/proliferation and having immunomodulatory effects. There are several immune dysregulations that can be noted when renal function declines. Physicians need to know well both the classical and nonclassical functions of vitamin D. This review is an analysis from the nephrologist's viewpoint and focuses on the relationship between the vitamin D and the immune system, together with vitamin's clinical use to treat kidney diseases.
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Correlation of interleukin-17-producing effector memory T cells and CD4+CD25+Foxp3 regulatory T cells with the phosphate levels in chronic hemodialysis patients.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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Hyperparathyroidism and hyperphosphatemia contribute to the inflammatory effects in chronic hemodialysis (HD) patients. Interleukin-17-producing CD4+ effector memory T (Th17) cells and CD4+CD25+Foxp3 regulatory T (Treg) cells both play critical roles in immune activation and inflammation. We investigated the relationship between the Treg and Th17 cells and the phosphate level in chronic HD patients.
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OmicCircos: A Simple-to-Use R Package for the Circular Visualization of Multidimensional Omics Data.
Cancer Inform
PUBLISHED: 01-01-2014
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OmicCircos is an R software package used to generate high-quality circular plots for visualizing genomic variations, including mutation patterns, copy number variations (CNVs), expression patterns, and methylation patterns. Such variations can be displayed as scatterplot, line, or text-label figures. Relationships among genomic features in different chromosome positions can be represented in the forms of polygons or curves. Utilizing the statistical and graphic functions in an R/Bioconductor environment, OmicCircos performs statistical analyses and displays results using cluster, boxplot, histogram, and heatmap formats. In addition, OmicCircos offers a number of unique capabilities, including independent track drawing for easy modification and integration, zoom functions, link-polygons, and position-independent heatmaps supporting detailed visualization.
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Lhx2 regulates a cortex-specific mechanism for barrel formation.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-21-2013
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LIM homeodomain transcription factors are critical regulators of early development in multiple systems but have yet to be examined for a role in circuit formation. The LIM homeobox gene Lhx2 is expressed in cortical progenitors during development and also in the superficial layers of the neocortex in maturity. However, analysis of Lhx2 function at later stages of cortical development has been hampered by severe phenotypes associated with early loss of function. We identified a particular Cre-recombinase line that acts in the cortical primordium after its specification is complete, permitting an analysis of Lhx2 function in neocortical lamination, regionalization, and circuit formation by selective elimination of Lhx2 in the dorsal telencephalon. We report a profound disruption of cortical neuroanatomical and molecular features upon loss of Lhx2 in the cortex from embryonic day 11.5. A unique feature of cortical circuitry, the somatosensory barrels, is undetectable, and molecular patterning of cortical regions appears disrupted. Surprisingly, thalamocortical afferents innervate the mutant cortex with apparently normal regional specificity. Electrophysiological recordings reveal a loss of responses evoked by stimulation of individual whiskers, but responses to simultaneous stimulation of multiple whiskers were present, suggesting that thalamic afferents are unable to organize the neurocircuitry for barrel formation because of a cortex-specific requirement of Lhx2. We report that Lhx2 is required for the expression of transcription factor paired box gene 6, axon guidance molecule Ephrin A5, and the receptor NMDA receptor 1. These genes may mediate Lhx2 function in the formation of specialized neurocircuitry necessary for neocortical function.
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Quantitative proteomics of protein complexes and their implications for cell reprograming and pluripotency.
J. Proteome Res.
PUBLISHED: 11-20-2013
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Pluripotency of embryonic stem cells (ESCs)/induced pluripotent stem cells (iPSCs) and reprograming of somatic cells (SCs) to pluripotency are governed by known and unknown factors. These factors, including protein complexes, are poorly described at the proteome level. Here, we established the quantitative proteomic profiles across three types of cells (iPSCs, ESCs, and SCs) using OFFGEL fractionation coupled with LTQ-Orbitrp analysis. Additionally, we utilized the previously published proteomic profiles of iPSCs, ESCs, and SCs. By integrating these proteomic profiles with protein-protein interaction resources, we identified numerous protein complexes in iPSCs and/or ESCs, which include known and novel chromatin remodeling complexes that facilitate cell reprograming. The identified protein complexes also include the previously unreported ones that are associated with the imperfect aspects of iPSCs or cell reprograming process. Further, we performed a comparison between our study and previously published studies and highlighted a partial conservation of the identified protein complexes across the iPSCs generated by different laboratories and iPS cell-type specific protein complexes. The identified protein complexes were validated by integrated in silico analysis of microarray repository data related to ESCs differentiation into embryoid bodies. A majority of the protein complexes exhibited significant (p < 0.005) co-regulation of their components upon ESC differentiation, suggesting their role in the maintenance of the pluripotent state. Finally, we showed a link between the components of the protein complexes and embryonic development using the existing loss-of-function phenotype data. Together, our integrated approach provides the first comprehensive view of the protein complexes that may have implications for cell reprograming and pluripotency.
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Molecular weight effect on the efficiency of polymer solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 11-11-2013
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In this study, we report the investigation of the influence of molecular weight (MW) on power conversion efficiency (PCE) of bulk heterojunction (BHJ) polymer solar cells (PSCs). It was found that PCEs of PSCs fabricated by poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7) blended with [6,6]-phenyl-C71 butyric acid methyl ester (PC71BM) as the active layer, are significantly enhanced from 5.41 to 6.27 and 8.50% along with the MW of PTB7 increased from 18 to 40 and 128 kg/mol, respectively. This enhancement is attributed to the enhanced light absorption and increased charge carrier mobility of PTB7 with high MW, and a proper phase separation in BHJ composite of PTB7:PC71BM interpenetrating network. All these results demonstrate that the MW of donor polymer plays an important role in the performance of BHJ PSCs.
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Thrombin Promotes Matrix Metalloproteinase-13 Expression through the PKC ? /c-Src/EGFR/PI3K/Akt/AP-1 Signaling Pathway in Human Chondrocytes.
Mediators Inflamm.
PUBLISHED: 10-16-2013
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Thrombin is a key mediator of fibrin deposition, angiogenesis, and proinflammatory processes. Abnormalities in these processes are primary features of rheumatoid arthritis and osteoarthritis. Matrix metalloproteinase-13 (MMP-13) may contribute to the breakdown of articular cartilage during arthritis. However, the role of thrombin in MMP-13 production in chondrocytes is unknown. In this study, we investigated the intracellular signaling pathways involved in thrombin-induced MMP-13 expression in human chondrocytes. We found that stimulation with thrombin led to increased secretion of MMP-13 in cultured human chondrocytes. Further, this thrombin-induced MMP-13 production was reduced after transfection with siRNAs against protease activated receptors 1 and 3 (PAR1 and PAR3), but not with PAR4 siRNA. Treatment with specific inhibitors for PKC ? , c-Src, EGFR, PI3K, Akt, or AP-1 or with the corresponding siRNAs against these signaling proteins also abolished the thrombin-mediated increase in MMP-13 production in chondrocytes. Our results provide evidence that thrombin acts through the PAR1/PAR3 receptors and activates PKC ? and c-Src, resulting in EGFR transactivation and activation of PI3K, Akt, and finally AP-1 on the MMP-13 promoter, thereby contributing to cartilage destruction during arthritis.
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Integrative transcriptome sequencing identifies trans-splicing events with important roles in human embryonic stem cell pluripotency.
Genome Res.
PUBLISHED: 10-16-2013
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Trans-splicing is a post-transcriptional event that joins exons from separate pre-mRNAs. Detection of trans-splicing is usually severely hampered by experimental artifacts and genetic rearrangements. Here, we develop a new computational pipeline, TSscan, which integrates different types of high-throughput long-/short-read transcriptome sequencing of different human embryonic stem cell (hESC) lines to effectively minimize false positives while detecting trans-splicing. Combining TSscan screening with multiple experimental validation steps revealed that most chimeric RNA products were platform-dependent experimental artifacts of RNA sequencing. We successfully identified and confirmed four trans-spliced RNAs, including the first reported trans-spliced large intergenic noncoding RNA ("tsRMST"). We showed that these trans-spliced RNAs were all highly expressed in human pluripotent stem cells and differentially expressed during hESC differentiation. Our results further indicated that tsRMST can contribute to pluripotency maintenance of hESCs by suppressing lineage-specific gene expression through the recruitment of NANOG and the PRC2 complex factor, SUZ12. Taken together, our findings provide important insights into the role of trans-splicing in pluripotency maintenance of hESCs and help to facilitate future studies into trans-splicing, opening up this important but understudied class of post-transcriptional events for comprehensive characterization.
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A prediction model for cognitive performance in health ageing using diffusion tensor imaging with graph theory.
Conf Proc IEEE Eng Med Biol Soc
PUBLISHED: 10-11-2013
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In this study, we employed diffusion tensor imaging (DTI) to construct brain structural network and then derive the connection matrices from 96 healthy elderly subjects. The correlation analysis between these topological properties of network based on graph theory and the Cognitive Abilities Screening Instrument (CASI) index were processed to extract the significant network characteristics. These characteristics were then integrated to estimate the models by various machine-learning algorithms to predict users cognitive performance. From the results, linear regression model and Gaussian processes model showed presented better abilities with lower mean absolute errors of 5.8120 and 6.25 to predict the cognitive performance respectively. Moreover, these extracted topological properties of brain structural network derived from DTI also could be regarded as the bio-signatures for further evaluation of brain degeneration in healthy aged and early diagnosis of mild cognitive impairment (MCI).
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A reproducible mechano-responsive luminescent system based on a discotic crown ether derivative doped with fluorophores: taking advantage of the phase transition of a matrix.
Chem. Commun. (Camb.)
PUBLISHED: 08-22-2013
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A reproducible mechano-responsive luminescent system based on a discotic crown ether derivative (1) doped with a small amount of fluorophore has been prepared. The emission intensity was enhanced when the material was subjected to mechanical shear with localized response.
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Bradykinin promotes vascular endothelial growth factor expression and increases angiogenesis in human prostate cancer cells.
Biochem. Pharmacol.
PUBLISHED: 08-07-2013
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Prostate cancer is the most commonly diagnosed malignancy in men and shows a tendency for metastasis to distant organs. Angiogenesis is required for metastasis. Bradykinin (BK) is an inflammatory mediator involved in tumor growth and metastasis, but its role in vascular endothelial growth factor (VEGF) expression and angiogenesis in human prostate cancer remains unknown. The aim of this study was to examine whether BK promotes prostate cancer angiogenesis via VEGF expression. We found that exogenous BK increased VEGF expression in prostate cancer cells and further promoted tube formation in endothelial progenitor cells and human umbilical vein endothelial cells. Pretreatment of prostate cancer with B2 receptor antagonist or small interfering RNA (siRNA) reduced BK-mediated VEGF production. The Akt and mammalian target of rapamycin (mTOR) pathways were activated after BK treatment, and BK-induced VEGF expression was abolished by the specific inhibitor and siRNA of the Akt and mTOR cascades. BK also promoted nuclear factor-?B (NF-?B) and activator protein 1 (AP-1) activity. Importantly, BK knockdown reduced VEGF expression and abolished prostate cancer cell conditional medium-mediated angiogenesis. Taken together, these results indicate that BK operates through the B2 receptor, Akt, and mTOR, which in turn activate NF-?B and AP-1, activating VEGF expression and contributing to angiogenesis in human prostate cancer cells.
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Extrinsic sphingosine 1-phosphate activates S1P5 and induces autophagy through generating endoplasmic reticulum stress in human prostate cancer PC-3 cells.
Cell. Signal.
PUBLISHED: 07-24-2013
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Sphingosine 1-phosphate (S1P) is a bioactive lysophospholipid that binds to a family of G protein-coupled receptors (GPCRs), termed S1P1-S1P5. Our previous study has reported that S1P induces autophagy in human prostate cancer PC-3 cell. In addition, S1P-induced autophagy plays a prosurvival role in PC-3 cells. Accumulating evidence has shown that the autophagy responses triggered by ER stress signaling have cytoprotective effects. Thus, we attempted to investigate whether S1P-induced autophagy is a result of triggering ER stress in PC-3 cells. By monitoring XBP-1 mRNA splicing, a characteristic of ER stress, we demonstrate that S1P triggers ER stress in a concentration-dependent and time-dependent manner. Moreover, DiH S1P, a membrane-nonpermeable S1P analog without intracellular effects also enhances ER stress. Meanwhile, we also show that S1P5 is required for S1P-induced ER stress by using RNA interference experiments. Furthermore, signaling analyses revealed that PI3K, PLC, and ROS production were involved in S1Ps effects on ER stress induction. On the other hand, knockdown of XBP-1 abolished S1P-induced autophagy. In summary, our results demonstrate for the first time that the extracellular S1P-triggered ER stress is responsible for autophagy induction in PC-3 cells.
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Ras activation mediates WISP-1-induced increases in cell motility and matrix metalloproteinase expression in human osteosarcoma.
Cell. Signal.
PUBLISHED: 07-12-2013
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WISP-1 is a cysteine-rich protein that belongs to the CCN (Cyr61, CTGF, Nov) family of matrix cellular proteins. Osteosarcoma is a type of highly malignant tumor with a potent capacity to invade locally and cause distant metastasis. However, the effect of WISP-1 on migration activity in human osteosarcoma cells is mostly unknown. In this study, we first found that the expression of WISP-1 in osteosarcoma patients was significantly higher than that in normal bone and corrected with tumor stage. Exogenous treatment of osteosarcoma cells with WISP-1 promoted cell motility and matrix metalloproteinase (MMP)-2 and MMP-9 expression. In addition, the Ras and Raf-1 inhibitor or siRNA abolished WISP-1-induced cell migration and MMP expression. On the other hand, activation of the Ras, Raf-1, MEK, ERK, and NF-?B signaling pathway after WISP-1 treatment was demonstrated, and WISP-1-induced expression of MMPs and migration activity were inhibited by the specific inhibitor, and mutant of MEK, ERK, and NF-?B cascades. Taken together, our results indicated that WISP-1 enhances the migration of osteosarcoma cells by increasing MMP-2 and MMP-9 expression through the integrin receptor, Ras, Raf-1, MEK, ERK, and NF-?B signal transduction pathway.
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Increased concentrations of plasma growth arrest-specific 6 and its soluble tyrosine kinase receptor sAxl in Taiwanese women with pelvic inflammatory disease.
Clin. Chim. Acta
PUBLISHED: 07-09-2013
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To investigate the concentrations of plasma growth arrest-specific protein 6 (Gas6) and its soluble tyrosine kinase receptor sAxl in women with pelvic inflammatory disease (PID) and their association with clinical outcomes of PID.
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Cloning, overexpression, purification and crystallization of malate dehydrogenase from Thermus thermophilus.
Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun.
PUBLISHED: 07-07-2013
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Malate dehydrogenase (MDH) has been used as a conjugate for enzyme immunoassay of a wide variety of compounds, such as drugs of abuse, drugs used in repetitive therapeutic application and hormones. In consideration of the various biotechnological applications of MDH, investigations of MDH from Thermus thermophilus were carried out to further understand the properties of this enzyme. The DNA fragment containing the open reading frame of mdh was amplified from the genomic DNA of T. thermophilus and cloned into the expression vector pET21b(+). The protein was expressed in a soluble form in Escherichia coli strain BL21(DE3). Homogeneous protein was obtained using a three-step procedure consisting of thermal treatment, Ni(2+)-chelating chromatography and size-exclusion chromatography. The purified MDH was crystallized and the crystals diffracted to a resolution of 1.80?Å on the BL13C1 beamline of the National Synchrotron Radiation Research Center (NSRRC), Taiwan. The crystals belonged to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 71.3, b = 86.1, c = 118.2?Å. The unit-cell volume of the crystal is compatible with the presence of two monomers in the asymmetric unit, with a corresponding Matthews coefficient VM of 2.52?Å(3)?Da(-1) and a solvent content of 51.2%. The crystal structure of MDH has been solved by molecular replacement and is currently under refinement.
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LHX2 regulates the neural differentiation of human embryonic stem cells via transcriptional modulation of PAX6 and CER1.
Nucleic Acids Res.
PUBLISHED: 06-26-2013
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The LIM homeobox 2 transcription factor Lhx2 is known to control crucial aspects of neural development in various species. However, its function in human neural development is still elusive. Here, we demonstrate that LHX2 plays a critical role in human neural differentiation, using human embryonic stem cells (hESCs) as a model. In hESC-derived neural progenitors (hESC-NPs), LHX2 was found to be expressed before PAX6, and co-expressed with early neural markers. Conditional ectopic expression of LHX2 promoted neural differentiation, whereas disruption of LHX2 expression in hESCs significantly impaired neural differentiation. Furthermore, we have demonstrated that LHX2 regulates neural differentiation at two levels: first, it promotes expression of PAX6 by binding to its active enhancers, and second, it attenuates BMP and WNT signaling by promoting expression of the BMP and WNT antagonist Cerberus 1 gene (CER1), to inhibit non-neural differentiation. These findings indicate that LHX2 regulates the transcription of downstream intrinsic and extrinsic molecules that are essential for early neural differentiation in human.
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Si-Wu-tang extract stimulates bone formation through PI3K/Akt/NF-kappaB signaling pathways in osteoblasts.
BMC Complement Altern Med
PUBLISHED: 06-18-2013
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Si-Wu-Tang (SWT), a Traditional Chinese Medicine (TCM) formula, is widely used for the treatment of gynopathies diseases such as menstrual discomfort, climacteric syndrome, dysmenorrhea, and other estrogen-related diseases. Recent studies have shown that SWT can treat primary dysmenorrhea, have anti-pruritic anti-inflammatory effects, and protect against radiation-induced bone marrow damage in an animal model. It has been reported that anti-inflammatory and anti-oxidant agents have the potential to treat osteoporosis by increasing bone formation and/or suppressing bone resorption. However, the effect of SWT on bone cell function has not yet been reported.
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Autophagy induction promotes aristolochic acid-I-induced renal injury in vivo and in vitro.
Toxicology
PUBLISHED: 06-18-2013
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Studies have found that ingestion of aristolochic acid (AA) causes nephropathy first by inducing renal tubular cell apoptosis acutely. It is currently unknown whether crosstalk between autophagy and apoptosis orchestrates the fate of tubular cells in acute AA nephropathy. We tested this hypothesis by acute administration of AA in vivo and in vitro. Autophagy was first induced in vivo through enhancing Atg5 and LC3-II expressions in kidneys of AA-I-treated rats. Punctuate LC3-GFP dots and autophagosomes were detected in this acute AA-I nephropathy rat model. We subsequently utilized normal rat renal proximal tubular epithelial cells (NRK52E) to study the autophagy mechanisms involved in acute AA-I nephropathy, with 100?M AA-I (median lethal dose 50) given in vitro. Cleavage of poly (ADP-ribose) polymerase (PARP), nuclear condensation, and fragmentation were demonstrated in the AA-I-treated NRK52E cells. Furthermore, AA-I induced Atg5 and LC3-II expressions and punctuated LC3-GFP dots. Autophagy flux by using lysosome inhibitor E64 induced the accumulation of LC3-II, which further promoted apoptosis through enhancing PARP cleavage. Inhibition of autophagy by 3-methyl adenine also led to the attenuation of AA-I-induced apoptosis, manifesting as decreased PARP cleavage, nuclei condensation, and decreased the number of cells negative for acridine orange/ethidium bromide staining. In addition, knockdown of Atg5 by short hairpin RNA attenuated LC3-II expression and PARP cleavage in NRK52E cells. Taken together, these findings suggested that the acute phase of AA-I-induced nephropathy is associated with induction of Atg5-dependent autophagy, which promotes renal tubular cell apoptosis.
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Early utilization of hypertonic peritoneal dialysate and subsequent risks of non-traumatic amputation among peritoneal dialysis patients: a nationwide retrospective longitudinal study.
BMC Nephrol
PUBLISHED: 06-13-2013
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The hemodialysis (HD) population has a particularly high incidence of amputation, which is likely associated with decreased tissue oxygenation during HD. However, information about the risk factors leading to amputation in peritoneal dialysis (PD) patients is limited. Here, we have investigated the association between the use of hypertonic peritoneal dialysate (HPD) and subsequent amputation in PD patients.
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Berberine Reduces the Metastasis of Chondrosarcoma by Modulating the ? v ? 3 Integrin and the PKC ? , c-Src, and AP-1 Signaling Pathways.
Evid Based Complement Alternat Med
PUBLISHED: 06-04-2013
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Chondrosarcoma is a primary malignant bone cancer, with a potent capacity to invade locally and cause distant metastasis, especially to the lungs. Patients diagnosed with chondrosarcoma have poor prognosis. Berberine, an active component of the Ranunculaceae and Papaveraceae families of plant, has been proven to induce tumor apoptosis and to prevent the metastasis of cancer cells. However, the effects of berberine in human chondrosarcoma are largely unknown. In this study, we found that berberine did not induce cell apoptosis in human primary chondrocytes and chondrosarcoma cells. However, at noncytotoxic concentrations, berberine reduced the migration and invasion of chondrosarcoma cancer cells. Integrins are the major adhesive molecules in mammalian cells and have been associated with the metastasis of cancer cells. We also found that incubation of chondrosarcoma cells with berberine reduced mRNA transcription for, and cell surface expression of, the ? v ? 3 integrin, with additional inhibitory effects on PKC ? , c-Src, and NF- ? B activation. Thus, berberine may be a novel antimetastasis agent for the treatment of metastatic chondrosarcoma.
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Apoptosis signal-regulating kinase 1 is involved in brain-derived neurotrophic factor (BDNF)-enhanced cell motility and matrix metalloproteinase 1 expression in human chondrosarcoma cells.
Int J Mol Sci
PUBLISHED: 05-21-2013
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Chondrosarcoma is the primary malignancy of bone that is characterized by a potent capacity to invade locally and cause distant metastasis, and is therefore associated with poor prognoses. Chondrosarcoma further shows a predilection for metastasis to the lungs. The brain-derived neurotrophic factor (BDNF) is a small molecule in the neurotrophin family of growth factors that is associated with the disease status and outcome of cancers. However, the effect of BDNF on cell motility in human chondrosarcoma cells is mostly unknown. Here, we found that human chondrosarcoma cell lines had significantly higher cell motility and BDNF expression compared to normal chondrocytes. We also found that BDNF increased cell motility and expression of matrix metalloproteinase-1 (MMP-1) in human chondrosarcoma cells. BDNF-mediated cell motility and MMP-1 up-regulation were attenuated by Trk inhibitor (K252a), ASK1 inhibitor (thioredoxin), JNK inhibitor (SP600125), and p38 inhibitor (SB203580). Furthermore, BDNF also promoted Sp1 activation. Our results indicate that BDNF enhances the migration and invasion activity of chondrosarcoma cells by increasing MMP-1 expression through a signal transduction pathway that involves the TrkB receptor, ASK1, JNK/p38, and Sp1. BDNF thus represents a promising new target for treating chondrosarcoma metastasis.
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C/EBP homologous protein deficiency aggravates acute pancreatitis and associated lung injury.
World J. Gastroenterol.
PUBLISHED: 05-09-2013
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To investigate the pathophysiological role of C/EBP homologous protein (CHOP) in severe acute pancreatitis and associated lung injury.
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