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Find video protocols related to scientific articles indexed in Pubmed.
Reduction of radiation dose in the spiral CT scan of the lumbar spine by the combined use of body mass index (BMI) and automatic exposure control (AEC).
J Xray Sci Technol
PUBLISHED: 11-20-2014
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The aim of this study was to investigate the significance of the combined use of BMI and AEC in reducing the radiation dose of CT volume scans of the lumbar spine.
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Transcription factor IRF8 plays a critical role in the development of murine basophils and mast cells.
Blood
PUBLISHED: 11-16-2014
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Basophils and mast cells play critical roles in host defense against pathogens and allergic disorders. However, the molecular mechanism by which these cells are generated is not completely understood. Here we demonstrate that interferon regulatory factor-8 (IRF8), a transcription factor essential for the development of several myeloid lineages, also regulates basophil and mast cell development. Irf8(-/-) mice displayed a severe reduction in basophil counts, which was accounted for by the absence of pre-basophil and mast cell progenitors (pre-BMPs). Although Irf8(-/-) mice retained peripheral tissue mast cells, remaining progenitors from Irf8(-/-) mice including granulocyte progenitors (GPs) were unable to efficiently generate either basophils or mast cells, indicating that IRF8 also contributes to the development of mast cells. IRF8 appeared to function at the GP stage, since IRF8 was expressed in GPs but not in basophils, mast cells, and basophil/mast cell-restricted progenitor cells. Furthermore, we demonstrate that GATA2, a transcription factor known to promote basophil and mast cell differentiation, acts downstream of IRF8. These results shed light on the pathways and the mechanism underlying the development of basophils and mast cells.
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Computer-Aided Diagnosis of Mammographic Masses Using Scalable Image Retrieval.
IEEE Trans Biomed Eng
PUBLISHED: 11-01-2014
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Computer-aided diagnosis of masses in mammograms is important to the prevention of breast cancer. Many approaches tackle this problem through content-based image retrieval (CBIR) techniques. However, most of them fall short of scalability in the retrieval stage, and their diagnostic accuracy is therefore restricted. To overcome this drawback, we propose a scalable method for retrieval and diagnosis of mammographic masses. Specifically, for a query mammographic region of interest (ROI), SIFT features are extracted and searched in a vocabulary tree, which stores all the quantized features of previously diagnosed mammographic ROIs. In addition, to fully exert the discriminative power of SIFT features, contextual information in the vocabulary tree is employed to refine the weights of tree nodes. The retrieved ROIs are then used to determine whether the query ROI contains a mass. The presented method has excellent scalability due to the low spatial-temporal cost of vocabulary tree. Extensive experiments are conducted on a large dataset of 11,553 ROIs extracted from the digital database for screening mammography (DDSM), which demonstrate the accuracy and scalability of our approach.
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Band gap opening in bilayer silicene by alkali metal intercalation.
J Phys Condens Matter
PUBLISHED: 10-29-2014
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Recently, bilayer and multilayer silicene have attracted increased attention following the boom of silicene, which holds great promise for future applications in microelectronic devices. Herein we systematically investigate all stacking configurations of bilayer silicene and the corresponding electronic properties. Strong coupling is found between two silicene layers, which destroys the Dirac cones in the band structures of pristine silicene and makes bilayer silicene sheets metallic. However, intercalation of alkali metal (especially potassium) can effectively decouple the interaction between two silicene layers. In the K-intercalated bilayer silicene (KSi4), the Dirac cones are recovered with a small band gap of 0.27 eV located about 0.55 eV below the Fermi level. Furthermore, intercalation of K(+) cations in bilayer silicene (K(+)Si4) results in a semiconductor with a moderate band gap of 0.43 eV, making it ideal for microelectronic applications.
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ErbB Receptors as Prognostic and Therapeutic Drug Targets in Bone and Soft Tissue Sarcomas.
Cancer Invest.
PUBLISHED: 10-27-2014
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ErbB receptors have been intensely studied to understand their importance in cancer biology and as therapeutic targets, and many ErbB inhibitors are now used in the clinical setting. A large number of studies have been conducted to examine the expression of ErbB family members in bone and soft tissue sarcomas, including osteosarcomas, synovial sarcomas, Ewing sarcomas, rhabdomyosarcomas, and so on. Nevertheless, the clinical implications of ErbB receptors remain elusive. To illustrate the potential of ErbB family members as prognostic and therapeutic drug targets in bone and soft tissue sarcomas, we summarized the molecular evidence and observations from clinical and basic trials.
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pH-Responsive Anionic Wormlike Micelle Based on Sodium Oleate Induced by NaCl.
J Phys Chem B
PUBLISHED: 10-22-2014
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A pH-responsive anionic surfactant wormlike micellar system induced by NaCl has been developed. In this work, the anionic surfactant, sodium oleate (NaOA) solutions, transforms from low-viscosity fluid into high-viscoelastic solution induced by NaCl of 200 mM to 350 mM concentration. According to the above, the solution reversibility has been studied via changing pH value of the solution. This pH-responsive solution can be promptly switched between gel-like solution and waterlike fluid in a narrow pH value range. Steady and dynamic rheological measurements are employed to characterize the pH-responsiveness at different pH. The transformation between wormlike micelle and spherical micelle in the various pH solutions is demonstrated by dynamic light scattering tests, cryo-TEM, and NMR measurements. The pH-responsive property of the system is attributed to the carboxylate ion contained by sodium oleate. With higher pH value, the ionized carboxylate combines with NaCl closely and thus forms wormlike micelles. On the contrary, sodium oleate converts to oleate acid when pH decreases. In this way, spherical micelles are transformed because of the weaker interaction between oleate aicd and NaCl.
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Interferon Regulatory Factor 8 (IRF8) Interacts with the BCL6 Corepressor, BCOR.
J. Biol. Chem.
PUBLISHED: 10-22-2014
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BCOR was discovered as a BCL6-interacting corepressor, but little is known about its other biological activities in normal B cell development and function. Previously, we found that interferon regulatory factor 8 (IRF8), also known as interferon consensus sequence-binding protein (ICSBP), directly targets a large number of genes in germinal center (GC) B cells including BCL6. In this study, we screened potential binding partners of IRF8 using a retrovirus-based protein complementation assay screen in a mouse pre-B cell line. We found that IRF8 interacts directly with BCOR and that the alpha helical region of IRF8 and the BCL6 binding domain (BBD) of BCOR are required for this interaction. In addition, IRF8 protein interacts directly with BCL6. Using a siRNA-mediated IRF8 knockdown mouse B cell lymphoma cell line, we showed that IRF8 represses BCOR and enhances BCL6 transcription. Taken together, these data suggest that a complex comprised of BCOR-BCL6-IRF8 modulates BCL6-associated transcriptional regulation of GC B cell function.
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Simultaneous targeting of PI3K? and a PI3K?-dependent MEK1/2-Erk1/2 pathway for therapy in pediatric B-cell acute lymphoblastic leukemia.
Oncotarget
PUBLISHED: 10-15-2014
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B cell acute lymphoblastic leukemia (B-ALL) is the most common hematological malignancy diagnosed in children, and blockade of the abnormally activated PI3K? displayed promising outcomes in B cell acute or chronic leukemias, but the mechanisms are not well understood. Here we report a novel PI3K? selective inhibitor X-370, which displays distinct binding mode with p110? and blocks constitutively active or stimulus-induced PI3K? signaling. X-370 significantly inhibited survival of human B cell leukemia cells in vitro, with associated induction of G1 phase arrest and apoptosis. X-370 abrogated both Akt and Erk1/2 signaling via blockade of PDK1 binding to and/or phosphorylation of MEK1/2. Forced expression of a constitutively active MEK1 attenuated the antiproliferative activity of X-370. X-370 preferentially inhibited the survival of primary pediatric B-ALL cells displaying PI3K?-dependent Erk1/2 phosphorylation, while combined inhibition of PI3K? and MEK1/2 displayed enhanced activity. We conclude that PI3K? inhibition led to abrogation of both Akt and Erk1/2 signaling via a novel PI3K-PDK1/MEK1/2-Erk1/2 signaling cascade, which contributed to its efficacy against B-ALL. These findings support the rationale for clinical testing of PI3K? inhibitors in pediatric B-ALL and provide insights needed to optimize the therapeutic strategy.
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Early predictors of acetabular growth after closed reduction in late detected developmental dysplasia of the hip.
J Pediatr Orthop B
PUBLISHED: 10-12-2014
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This study evaluates improvement of the acetabular index (AI) in patients with developmental dysplasia of the hip at 4 years after closed reduction, and determines the association between the final AI and a set of factors. Sixty-two patients (74 hips) treated with closed reduction were categorized into three groups according to age: group A (0-12 months, 18 hips), group B (13-18 months, 24 hips), and group C (>18 months, 32 hips). There was no difference in AI among the three groups before reduction (P=0.293). In groups A and C, the AI decreased significantly over time until 3 years after reduction and no differences were observed between the time points of 3 and 4 years. At 4 years after reduction, the AI of group C was significantly higher than that of groups A (P<0.001) and B (P=0.012). The overall AI improvement rate was 28.63%. The AI improvement rate of group A was significantly higher than that of group C (P=0.005). Pearson correlation analysis indicated no correlation between center-head distance discrepancy and the final AI (P=0.811). Linear regression suggested that age and initial AI correlated significantly with the final AI (R=0.617, F=15.031, P<0.001). Other factors, such as sex, center-edge angle of Wiberg, bilaterally involved, and avascular necrosis of the femoral head, showed no correlations with the final AI (P>0.05). According to the coefficients, initial AI (?1=0.432, P<0.001) had greater effect than age (?2=0.197, P=0.023) on the final AI. In conclusion, the AI decreases in all patients after reduction and stabilizes at 3 years after reduction. The AI improvement rate is correlated negatively with age. Age and initial AI are early predictors of the progress of AI after closed reduction in developmental dysplasia of the hip patients.
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Ovariectomy-induced osteopenia influences the middle and late periods of bone healing in a mouse femoral osteotomy model.
Rejuvenation Res
PUBLISHED: 10-10-2014
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Objective It is known that bone healing was delayed in the presence of osteoporosis in humans. However, due to the complexities of the healing of osteoporotic fractures, animal models may be more appropriate to study the effects of osteoporosis in more details and to test drugs on the fracture repair process. The purpose of this study was to investigate the influence of ovariectomy-induced osteopenia in bone healing in an open femoral osteotomy model, and to test the feasibility of this model for evaluating the healing process under osteopenic conditions. Methods In assessing the effects of osteopenia on fracture healing, ovariectomized mouse models were employed. A mid-shaft femur osteotomy model was also established 3 weeks after ovariectomy as an osteopenic fracture group (OVX group). Femurs were then harvested at 2 weeks and 6 weeks after fracture for X-ray radiography, micro-computed tomography (micro-CT), histology and biomechanical analysis. A sham-operated group (Sham group) was used for comparison. Results The OVX mice had significantly lower BVF, vBMD and TMD in the fracture calluses at 6 weeks (P < 0.05), and similar trend was observed in 2 weeks. Additionally, larger calluses in OVX animals were observed via micro-CT and X-ray, but these did not result in better healing outcomes as determined by biomechanical test at 6 weeks. Histological images of the healing fractures in the OVX mice found forward of broken end resorption and delay of hard callus remodeling. The impaired biomechanical measurements in the OVX group (P < 0.05) were consistent with micro-CT measurements and radiographic scoring, which also indicated delay in fracture healing of the OVX group. Conclusions This study provided evidences that ovariectomy-induced osteopenia impair the middle and late bone healing process once more. These data also supported the validity of the mouse femoral osteotomy model in evaluating the process of bone healing under osteopenic conditions.
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The transcription factors IRF8 and PU.1 negatively regulate plasma cell differentiation.
J. Exp. Med.
PUBLISHED: 10-06-2014
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Activated B cells undergo immunoglobulin class-switch recombination (CSR) and differentiate into antibody-secreting plasma cells. The distinct transcriptomes of B cells and plasma cells are maintained by the antagonistic influences of two groups of transcription factors: those that maintain the B cell program, including BCL6 and PAX5, and plasma cell-promoting factors, such as IRF4 and BLIMP-1. We show that the complex of IRF8 and PU.1 controls the propensity of B cells to undergo CSR and plasma cell differentiation by concurrently promoting the expression of BCL6 and PAX5 and repressing AID and BLIMP-1. As the PU.1-IRF8 complex functions in a reciprocal manner to IRF4, we propose that concentration-dependent competition between these factors controls B cell terminal differentiation.
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The 3'-5' DNA Exonuclease TREX1 Directly Interacts with Poly(ADP-ribose) Polymerase-1 (PARP1) During the DNA Damage Response.
J. Biol. Chem.
PUBLISHED: 10-02-2014
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The main function of the 3'-5' DNA exonuclease TREX1 is to digest cytosolic single-stranded DNA to prevent activation of cell-intrinsic responses to immunostimulatory DNA. TREX1 translocates to the nucleus following DNA damage with its nuclear activities being less well defined. Although mutations in human TREX1 have been linked to autoimmune/inflammatory diseases, the mechanisms contributing to the pathogenesis of these diseases remain incompletely understood. Here, using mass spectrometry and co-immunoprecipitation assays and in vivo over-expression models, we show that TREX1 interacts with poly(ADP-ribose) polymerase-1 (PARP1), a nuclear enzyme involved in the DNA damage response. Two zinc finger domains at the amino-terminus of PARP1 were required for the interaction with TREX1 that occurs after nuclear translocation of TREX1 in response to DNA damage. Functional studies suggested that TREX1 may contribute to stabilization of PARP1 levels in the DNA damage response and its activity. These results provide new insights into the mechanisms of single-stranded DNA repair following DNA damage and alterations induced by gene mutations.
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Tuning the band gap in silicene by oxidation.
ACS Nano
PUBLISHED: 09-30-2014
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Silicene monolayers grown on Ag(111) surfaces demonstrate a band gap that is tunable by oxygen adatoms from semimetallic to semiconducting type. With the use of low-temperature scanning tunneling microscopy, we find that the adsorption configurations and amounts of oxygen adatoms on the silicene surface are critical for band gap engineering, which is dominated by different buckled structures in ?13 × ?13, 4 × 4, and 2?3 × 2?3 silicene layers. The Si-O-Si bonds are the most energy-favored species formed on ?13 × ?13, 4 × 4, and 2?3 × 2?3 structures under oxidation, which is verified by in situ Raman spectroscopy as well as first-principles calculations. The silicene monolayers retain their structures when fully covered by oxygen adatoms. Our work demonstrates the feasibility of tuning the band gap of silicene with oxygen adatoms, which, in turn, expands the base of available two-dimensional electronic materials for devices with properties that is hardly achieved with graphene oxide.
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Design and application of quadrature compensation patterns in bulk silicon micro-gyroscopes.
Sensors (Basel)
PUBLISHED: 09-17-2014
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This paper focuses on the detailed design issues of a peculiar quadrature reduction method named system stiffness matrix diagonalization, whose key technology is the design and application of quadrature compensation patterns. For bulk silicon micro-gyroscopes, a complete design and application case was presented. The compensation principle was described first. In the mechanical design, four types of basic structure units were presented to obtain the basic compensation function. A novel layout design was proposed to eliminate the additional disturbing static forces and torques. Parameter optimization was carried out to maximize the available compensation capability in a limited layout area. Two types of voltage loading methods were presented. Their influences on the sense mode dynamics were analyzed. The proposed design was applied on a dual-mass silicon micro-gyroscope developed in our laboratory. The theoretical compensation capability of a quadrature equivalent angular rate no more than 412 °/s was designed. In experiments, an actual quadrature equivalent angular rate of 357 °/s was compensated successfully. The actual compensation voltages were a little larger than the theoretical ones. The correctness of the design and the theoretical analyses was verified. They can be commonly used in planar linear vibratory silicon micro-gyroscopes for quadrature compensation purpose.
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Expression of Cre Recombinase in Alveolar Epithelial Cells of the AQP2-Cre Transgenic Mini-Pigs.
Cell. Physiol. Biochem.
PUBLISHED: 09-10-2014
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Background/Aims: Optimal use of Cre mediated recombination in conditional animal models depends on well characterized Cre driver lines. Unfortunately, some Cre driver lines exhibit unexpected expression patterns hindering their utility in Cre/loxP systems. Thus, systematic assessment of new Cre lines is essential for generating useful Cre driver lines for future studies. Methods: Here, we describe a Cre Transgenic (Tg) mini-pig line in which the expression of Cre is directed by a 3-kb 5' fragment of the kidney-specific aquaporin 2 (AQP2); however, the AQP2-Cre Tg mini-pig line exhibits expression of Cre in alveolar epithelial cells (AECs) instead of collecting duct cells. The specificity of the AQP2-Cre plasmid was validated in vitro, and indicating that the AQP2-Cre was specifically expressed in the transfected LLC-PK1 cells. Absolute quantitative real-time PCR (qRT-PCR) and inverse PCR were performed to determine the copy numbers and integration sites of the AQP2-Cre transgene. Relative qRT-PCR was performed to evaluate variation in Cre expression levels over time. Results: Our data indicated that this AQP2-Cre Tg mini-pig line exhibits stable expression of Cre recombinase over time and in subsequent generations, even though the AQP2-Cre transgene was segregated and reduced in subsequent generations. Conclusion: Combined with our previous studies of the activity of this Cre, we conclude that this Cre Tg mini-pig line will provide a reliable tool for generating lung-specific gene targeting mini-pig models, thereby allowing the investigation of gene functions in lung development and studying the molecular mechanisms of human lung disease. © 2014 S. Karger AG, Basel.
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Coordination of Swarming Motility, Biosurfactant Synthesis, and Biofilm Matrix Exopolysaccharide Production in Pseudomonas aeruginosa.
Appl. Environ. Microbiol.
PUBLISHED: 08-29-2014
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Biofilm formation is a complex process in which many factors are involved. Bacterial swarming motility and exopolysaccharides both contribute to biofilm formation, yet it is unclear how bacteria coordinate swarming motility and exopolysaccharide production. Psl and Pel are two key biofilm matrix exopolysaccharides in Pseudomonas aeruginosa. This opportunistic pathogen has three types of motility, swimming, twitching, and swarming. In this study, we found that elevated Psl and/or Pel production reduced the swarming motility of P. aeruginosa but had little effect on swimming and twitching. The reduction was due to decreased rhamnolipid production with no relation to the transcription of rhlAB, two key genes involved in the biosynthesis of rhamnolipids. Rhamnolipid-negative rhlR and rhlAB mutants synthesized more Psl, whereas exopolysaccharide-deficient strains exhibited a hyperswarming phenotype. These results suggest that competition for common sugar precursors catalyzed by AlgC could be a tactic for P. aeruginosa to balance the synthesis of exopolysaccharides and rhamnolipids and to control bacterial motility and biofilm formation inversely because the biosynthesis of rhamnolipids, Psl, and Pel requires AlgC to provide the sugar precursors and an additional algC gene enhances the biosynthesis of Psl and rhamnolipids. In addition, our data indicate that the increase in RhlI/RhlR expression attenuated Psl production. This implied that the quorum-sensing signals could regulate exopolysaccharide biosynthesis indirectly in bacterial communities. In summary, this study represents a mechanism that bacteria utilize to coordinate swarming motility, biosurfactant synthesis, and biofilm matrix exopolysaccharide production, which is critical for biofilm formation and bacterial survival in the environment.
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Modulation of cytokine expression in human macrophages by endocrine-disrupting chemical Bisphenol-A.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-13-2014
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Exposure to environmental endocrine-disrupting chemical Bisphenol-A (BPA) is often associated with dysregulated immune homeostasis, but the mechanisms remain unclear. In the present study, the effects of BPA on the cytokines responses of human macrophages were investigated. Treatment with BPA increased pro-inflammation cytokines tumor necrosis factor-? (TNF-?) and interleukin-6 (IL-6) production, but decreased anti-inflammation cytokines interleukin-10 (IL-10) and transforming growth factor-? (TGF-?) production in THP1 macrophages, as well as in primary human macrophages. BPA effected cytokines expression through estrogen receptor ?/? (ER?/?)-dependent mechanism with the evidence of ER?/? antagonist reversed the expression of cytokines. We also identified that activation of extracellular regulated protein kinases (ERK)/nuclear factor ?B (NF-?B) signal cascade marked the effects of BPA on cytokines expression. Our results indicated that BPA effected inflammatory responses of macrophages via modulating of cytokines expression, and provided a new insight into the link between exposure to BPA and human health.
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Inhibition of HMG-CoA reductase increases the expression of IFN-responsive genes.
Clin. Exp. Pharmacol. Physiol.
PUBLISHED: 08-12-2014
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The HMG-CoA reductase (HMGCR) pathway is an important metabolic route that is present in almost every organism. However, whether HMGCR affects the expression of IFN-responsive genes is unclear. In this study, expression levels of IFN-responsive genes were monitored by real time PCR and ELISA. The results showed that expression levels of IFN-responsive genes were significantly increased in HMGCR-downregulated cells and HMGCR inhibitor-treated cells, indicating that inhibition of HMGCR activates the expression of IFN-responsive genes. The result in this study will give new insight into the role of HMG-CoA reductase in antiviral research. This article is protected by copyright. All rights reserved.
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Knee moment and shear force are correlated with femoral tunnel orientation after single-bundle anterior cruciate ligament reconstruction.
Am J Sports Med
PUBLISHED: 07-25-2014
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Increasing evidence has shown that anatomic single-bundle anterior cruciate ligament reconstruction (ACLR) better restores normal knee kinematics and functionality than nonanatomic ACLR. Whether anatomic reconstruction results in better knee kinetics during daily activities has not been fully investigated.
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DNA methylation-mediated silencing of neuronatin (NNAT) in pig parthenogenetic fetuses.
Gene
PUBLISHED: 07-18-2014
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It is generally believed that aberrant expression of imprinted genes participates in growth retardation of mammalian parthenogenesis. Neuronatin (NNAT), a paternally expressed gene, plays important roles in neuronal growth and metabolic regulation. Here we have compared the gene expression and promoter methylation pattern of NNAT between pig normally fertilized (Con) and parthenogenetic (PA) embryos. The results showed loss of NNAT expression (p<0.001) and hypermethylation of NNAT promoter in PA samples. Additionally, partial methylation was observed in Con fetuses, while almost full methylation and unmethylation of NNAT promoter were apparent in Metaphase II (MII) oocytes and mature sperms, respectively, which identified the CpG promoter region as a putative differentially methylated region (DMR) of NNAT. The data demonstrate that promoter hypermethylation is associated with the silencing of NNAT in pig PA fetuses, which may be related to developmental failure of pig parthenogenesis at early stages.
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The Expression and Role of MEKK3 in Renal Clear Cell Carcinoma.
Anat Rec (Hoboken)
PUBLISHED: 07-14-2014
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To explore the relationship between Mitogen-activated protein kinase/extracellular signal-regulated kinase kinase kinase 3(MEKK3) and cell apoptosis, clinicopathology and prognosis, we characterize the expression of MEKK3, survivin and stat3 in renal clear cell carcinoma (RCCC). The expressions were measured by RT-PCR and Western blot from 15 cases of RCCC and 15 cases of control group (CG). Protein expression was detected by tissue microarray and immunochemistry in 98 cases of RCCC, 28 cases of CG. Expression patterns were analyzed for their association with pathological factors, correlation and prognosis in RCCC. Expression of MEKK3, survivin and stat3 mRNA was significantly higher in RCCC than in CG (P < 0.01). MEKK3, survivin and stat3 expression differed significantly between pathological grade (P < 0.05) and clinical stage (P < 0.05). MEKK3 expression was positively correlated with survivin and stat3 (P < 0.01). Furthermore, we investigated the role of MEKK3 in RCCC using the technique of RNA silencing via small interfering (siRNA) in ACHN cells. The results indicated that the targeted depletion of MEKK3 caused a dramatic massive apoptotic cell death. Kaplan-Meier survival analysis showed that MEKK3 and survivin expression, pathological grade, and clinical stage reduced cumulative survival. Cox multivariate regression analysis showed that MEKK3, survivin, and clinical staging were independent prognostic factors in renal cancer (P < 0.05). MEKK3 can be used as an important marker of prognostic evaluation in RCCC. The mechanism may be closely related to cell apoptosis. Targeted therapy of MEKK3 may provide a new strategy for treatment of chemotherapeutic-resistant tumors. Anat Rec, 2014. © 2014 Wiley Periodicals, Inc.
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A reporter mouse reveals lineage-specific and heterogeneous expression of IRF8 during lymphoid and myeloid cell differentiation.
J. Immunol.
PUBLISHED: 07-14-2014
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The IFN regulatory factor family member 8 (IRF8) regulates differentiation of lymphoid and myeloid lineage cells by promoting or suppressing lineage-specific genes. How IRF8 promotes hematopoietic progenitors to commit to one lineage while preventing the development of alternative lineages is not known. In this study, we report an IRF8-EGFP fusion protein reporter mouse that revealed previously unrecognized patterns of IRF8 expression. Differentiation of hematopoietic stem cells into oligopotent progenitors is associated with progressive increases in IRF8-EGFP expression. However, significant induction of IRF8-EGFP is found in granulocyte-myeloid progenitors and the common lymphoid progenitors but not the megakaryocytic-erythroid progenitors. Surprisingly, IRF8-EGFP identifies three subsets of the seemingly homogeneous granulocyte-myeloid progenitors with an intermediate level of expression of EGFP defining bipotent progenitors that differentiation into either EGFP(hi) monocytic progenitors or EGFP(lo) granulocytic progenitors. Also surprisingly, IRF8-EGFP revealed a highly heterogeneous pre-pro-B population with a fluorescence intensity ranging from background to 4 orders above background. Interestingly, IRF8-EGFP readily distinguishes true B cell committed (EGFP(int)) from those that are noncommitted. Moreover, dendritic cell progenitors expressed extremely high levels of IRF8-EGFP. Taken together, the IRF8-EGFP reporter revealed previously unrecognized subsets with distinct developmental potentials in phenotypically well-defined oligopotent progenitors, providing new insights into the dynamic heterogeneity of developing hematopoietic progenitors.
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Synthesis of hollow mesoporous silica nanoparticles with tunable shell thickness and pore size using amphiphilic block copolymers as core templates.
Dalton Trans
PUBLISHED: 06-25-2014
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This paper presents a facile method for the fabrication of uniform hollow mesoporous silica nanoparticles (HMSNs) with tunable shell thickness and pore size. In this method, a series of amphiphilic block copolymers of polystyrene-b-poly (acrylic acid) (PS-b-PAA) with different hydrophobic block (PS) lengths were first synthesized via atom transfer radical polymerization (ATRP). The as-synthesized PS-b-PAA and cetyltrimethylammonium bromide (CTAB) were subsequently used as co-templates to fabricate HMSNs. This approach allows the control of shell thickness and pore size distribution of the synthesized HMSNs simply by changing the amounts of PS-b-PAA and CTAB, respectively. In vitro cytotoxicity and hemolysis assays demonstrated that the synthesized HMSNs had a low and shell thickness-dependent cytotoxicity and hemolytic activity. Therefore, these HMSNs have great potential for biomedical applications due to their good biocompatibility and ease of synthesis.
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RNAi-mediated silencing of the Skp-2 gene causes inhibition of growth and induction of apoptosis in human renal carcinoma cells.
Int J Clin Exp Pathol
PUBLISHED: 06-15-2014
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Renal cancer ranks one of the most frequent causes of cancer death in the world. S-phase kinase-associated protein 2 (SKP 2) is overexpressed in human tumors and has prognostic value in many cancers including renal cancer, indicating its potential as a therapeutic target. In this study, we investigated the therapeutic potential of Skp-2 in renal cancer using the technique of RNA silencing via short hairpin RNA (shRNA). Synthetic shRNA duplexes against Skp-2 were introduced to down-regulate the expression of Skp-2 in a highly malignant renal carcinoma cell line, ACHN. The results indicated that siRNA targeting of Skp-2 could lead to an efficient and specific inhibition of endogenous Skp-2 activity. Furthermore, we found that depletion of Skp-2 caused a dramatic cell cycle arrest, followed by massive apoptotic cell death, and eventually resulted in a significant decrease in growth, viability and tumor formation in renal cancer cell lines studied.
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A preliminary study of the relationship between breast cancer metastasis and loss of heterozygosity by using exome sequencing.
Sci Rep
PUBLISHED: 06-09-2014
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We explored the feasibility of studying loss of heterozygosity (LOH) by using exome sequencing and compared the differences in genetic LOH between primary breast tumors and metastatic lesions. Exome sequencing was conducted to investigate the genetic LOH in the peripheral blood, a primary tumor, and a metastatic lesion from the same patient. LOH was observed in 30 and 48 chromosomal loci of the primary tumor and metastatic lesion, respectively. The incidence of LOH was the highest on chromosome 19, followed by chromosomes 14, 3, and 11 in the metastatic lesion. Among these 'hot' regions, LOH was observed for multiple genes of the CECAM, MMP and ZNF families. Therefore, the use of exome sequencing for studying LOH is feasible. More members of gene families appeared with LOH in 'hot' regions, suggesting that these gene families had synergistic effects in tumorigenesis.
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Anoxic stress and rapid cold hardening enhance cold tolerance of the migratory locust.
Cryobiology
PUBLISHED: 05-02-2014
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Anoxia and rapid cold hardening (RCH) can increase the cold tolerance of many animals. However, mechanisms underlying these two kinds of stresses remain unclear. In this study, we aimed to explore the relationship of acclimation to cold stress with acclimation to anoxic stress in the migratory locust, Locusta migratoria. RCH at 0°C for 3h promoted the survival of cold stress-exposed locusts. Anoxic hypercapnia (CO2 anoxic treatment) for 40 min exerted an effect similar to that of RCH. Anoxic hypercapnia within 1h can all promote the cold hardiness of locusts. We investigated the transcript levels of six heat shock protein (Hsp) genes, namely, Hsp20.5, Hsp20.6, Hsp20.7, Hsp40, Hsp70, and Hsp90. Four genes, namely, Hsp90, Hsp40, Hsp20.5, and Hsp20.7, showed differential responses to RCH and anoxic hypercapnia treatments. Under cold stress, locusts exposed to the two regimens showed different responses for Hsp90, Hsp20.5, and Hsp20.7. However, the varied responses disappeared after recovery from cold stress. Compared with the control group, the transcript levels of six Hsp genes were generally downregulated in locusts subjected to anoxic hypercapnia or/and RCH. These results indicate that anoxic stress and RCH have different mechanisms of regulating the transcription of Hsp family members even if the two treatments exerted similar effects on cold tolerance of the migratory locust. However, Hsps may not play a major role in the promotion of cold hardiness by the two treatments.
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On bandwidth characteristics of tuning fork micro-gyroscope with mechanically coupled sense mode.
Sensors (Basel)
PUBLISHED: 04-29-2014
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The bandwidth characteristics of a tuning fork micro-gyroscope with mechanically coupled sense mode were investigated in this paper to provide some references for mechanical bandwidth design. The concept of sense mode mechanical coupling is introduced first. Theoretical frequency response analyses were then carried out on the mechanical part of the gyroscope. Equations representing the relationships between the differential output signal and the frequency of the input angular rate were deduced in full frequency range and further simplified in low frequency range. Based on these equations, bandwidth characteristics under ideal and non-ideal conditions are discussed. Analytical results show that under ideal conditions, the bandwidth characteristics of a tuning fork micro-gyroscope are similar to those of a single mass micro-gyroscope, but under non-ideal conditions, especially when sense mass and/or stiffness are asymmetric, the bandwidth characteristics would be quite different because the in-phase mode would participate in the anti-phase vibration response. Experimental verifications were carried out on two micro-gyroscope prototypes designed in our laboratory. The deduced equations and analytical results can be used in guiding the mechanical bandwidth design of tuning fork micro-gyroscopes with mechanically coupled sense mode.
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Bone Plug Versus Suture-Only Fixation of Meniscal Grafts: Effect on Joint Contact Mechanics During Simulated Gait.
Am J Sports Med
PUBLISHED: 04-28-2014
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Meniscus allograft transplantation (MAT) is primarily undertaken to relieve the symptoms associated with meniscal deficiencies. However, its ability to restore normal knee joint contact mechanics under physiological loads is still unclear.
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Analysis of molecular variation in porcine reproductive and respiratory syndrome virus in China between 2007 and 2012.
Virol Sin
PUBLISHED: 04-23-2014
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In the present study, 89 porcine reproductive and respiratory syndrome virus (PRRSV) isolates in China during 2007 to 2012 were randomly selected from the GenBank genetic sequence database. Evolutionary characteristics of these isolates were analyzed based on the sequences of non-structural protein 2 (Nsp2) and glycoprotein 5 (GP5). The genetic variations of the isolates were also compared with six representative strains. The results showed that a high degree of genetic diversity exists among the PRRSV population in China. Highly pathogenic PRRSV isolates, with a discontinuous deletion of a 30 amino acid residue in the Nsp2 region, remained the most dominant virus throughout 2007-2012 in China. Owing to the extensive use of representative vaccine strains, natural recombination events occurred between strains. Three isolates - HH08, DY, and YN-2011 - were more closely related to vaccine strains than the other isolates. Both YN-2011 and DY were the evolutionary products of recombination events between strains SP and CH-1R. The results of the present study provide useful information for the epidemiology of PRRSV as well as for vaccine development.
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[Value of dual-phase (18)F-FDG PET/CT in preoperative staging of bladder cancer].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 04-23-2014
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To investigate the clinical value of dual-phase (18)F-FDG PET/CT with oral diuretics in preoperative staging of bladder cancer.
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Cell infiltration and vascularization in porous nanoyarn scaffolds prepared by dynamic liquid electrospinning.
J Biomed Nanotechnol
PUBLISHED: 04-17-2014
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A novel electrospun nanoyarn scaffold, aimed to improve cell infiltration and vascularization, as well as guide cell behaviors by its biomimetic structure, was fabricated for tissue engineering. Electrospun nanofibers were deposited and twisted into yarns in a water vortex before collecting on a rotating mandrel to form a nanoyarn scaffold. Field emission-scanning electronic microscope (FE-SEM) images revealed that the scaffold, composed of aligned nanoyarns (24 micro m) which were composed of a bundle of nanofibers, created a porous structure which may be conducive to cellular infiltration. Thus, we hypothesized that the biomimetic nanoyarn will have a positive influence on cell proliferation and morphology. Pig iliac endothelial cells (PIECs) and MC3T3-E1 pre-osteoblastic cells cultured on the nanoyarn scaffolds showed significantly higher proliferation rates than that on traditional electrospun nanofiber scaffolds. Histological analysis demonstrated that cells infiltrate throughout the nanoyarn scaffolds over a 10-day period, however, no cell infiltration was observed on the nanofiber scaffolds. Moreover, confocal microscopy images indicated that both PIECs and MC3T3-E1 pre-osteoblastic cells cultured on the nanoyarn scaffolds exhibit an extremely elongated morphology compared to the flattened morphology when cells were cultured on electrospun nanofiber scaffolds or tissue culture plates. Furthermore, complex capillary-like structures were observed when PIECs cultured on the nanoyarn scaffold for 7 days, indicating that the nanoyarns provide templates and topographical cues for the assembly of PIECs and the promotion of a capillary network in vitro. In conclusion, the positive cellular interactions on the nanoyarn scaffold demonstrate potential application for use in tissue engineering.
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Nitro-oleic acid downregulates lipoprotein-associated phospholipase A2 expression via the p42/p44 MAPK and NF?B pathways.
Sci Rep
PUBLISHED: 04-11-2014
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Nitro-oleic acid (OA-NO2), acting as anti-inflammatory signaling mediators, are involved in multiple signaling pathways. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is well known as a cardiovascular risk biomarker. Our results showed that OA-NO2 downregulated the expression of Lp-PLA2 in a time- and dose-dependent manner, whereas native OA had no such effect. Furthermore, OA-NO2 could repress Lp-PLA2 expression in the peripheral blood mononuclear cells of apo CIII-transgenic (apo CIII TG) pigs, which exhibited higher Lp-PLA2 expression and activity than did wild-type (WT) pigs. OA-NO2 inhibited Lp-PLA2 expression in macrophages, independent of nitric oxide formation and PPAR?-activation. However, OA-NO2 downregulates Lp-PLA2 by inhibiting the p42/p44 mitogen-activated protein kinase (MAPK) and the nuclear factor ?B (NF?B) pathways. When used to mediate anti-inflammatory signaling, the regulation of inflammatory cytokines and SOD by OA-NO2 might be associated with the reduction of Lp-PLA2. These results suggested that OA-NO2 might exert a vascular-protective effect partially via Lp-PLA2 inhibition.
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Fufang Kushen injection inhibits sarcoma growth and tumor-induced hyperalgesia via TRPV1 signaling pathways.
Cancer Lett.
PUBLISHED: 04-09-2014
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Cancer pain is a deleterious consequence of tumor growth and related inflammation. Opioids and anti-inflammatory drugs provide first line treatment for cancer pain, but both are limited by side effects. Fufang Kushen injection (FKI) is GMP produced, traditional Chinese medicine used alone or with chemotherapy to reduce cancer-associated pain. FKI limited mouse sarcoma growth both in vivo and in vitro, in part, by reducing the phosphorylation of ERK and AKT kinases and BAD. FKI inhibited TRPV1 mediated capsaicin-induced ERK phosphorylation and reduced tumor-induced proinflammatory cytokine production. Thus, FKI limited cancer pain both directly by blocking TRPV1 signaling and indirectly by reducing tumor growth.
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Imbalance between MMP-2, 9 and TIMP-1 promote the invasion and metastasis of renal cell carcinoma via SKP2 signaling pathways.
Tumour Biol.
PUBLISHED: 03-31-2014
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S-phase kinase-associated protein-2 (Skp2) is overexpressed in human cancers and acted as an oncogenic protein associated with poor prognosis by enhancing tumor metastasis. The present study has demonstrated that Skp2 overexpresses stable transfectants from 786-0 human renal cancer cells. We found that these stable transfectants exhibited increased migratory and invasive abilities. In addition, expression of matrix metalloproteinase-2 (MMP-2) and MMP-9 was upregulated and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) was downregulated. In contrast, RNA interference-mediated knockdown Skp2 expression suppressed the ability of ACHN cells to migratory and invasive. Skp2 depletion increased P27 and decreased cyclin E activity, and then induced cell cycle arrest in the G0/G1 phase. Skp2 depletion also downregulated MMP-2 and MMP-9, while upregulated the TIMP-1 activity and expression. The results suggest that Skp2 signaling pathways promoted the ability to metastasize, by stimulating cell proliferation and increasing the ratio of MMP-2 and MMP-9/TIMP-1. So, in conclusion, we provide the first evidence that the imbalance of MMP/TIMP, including upregulation of MMP-2 and MMP-9 and downregulation of TIMP-1, is one of the mechanisms by which Skp2 promotes cell invasion.
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Pathogenesis and regulation of cellular proliferation in acute lymphoblastic leukemia - the role of Ikaros.
J BUON
PUBLISHED: 03-25-2014
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Acute lymphoblastic leukemia (ALL) is the most common type of leukemia of childhood. Over the last 50 years there have been tremendous scientific advances in understanding the pathogenesis and the mechanisms that control cellular proliferation in ALL. These discoveries led to the development of efficient therapeutic regimens that greatly improved survival of children with ALL. Recently, several genes have been demonstrated to play a key role in tumor suppression and that their deregulation leads to malignant transformation and can affect overall survival. This review summarizes the role of Ikaros (IKZF1) in tumor suppression and regulation of gene expression in leukemia. Deletions and/or mutations of Ikaros have been detected in a large percentage of pediatric and adult ALL and reduced Ikaros function has been associated with poor outcome in ALL. Ikaros function in chromatin remodeling and epigenetic regulation of gene transcription emphasizes the important role of this protein in controlling cellular proliferation. In this review, we particularly focus on the role of signaling pathways in the regulation of Ikaros activity and its transcriptional control in leukemia.
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HMG-CoA reductase is negatively associated with PCV2 infection and PCV2-induced apoptotic cell death.
J. Gen. Virol.
PUBLISHED: 03-18-2014
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We examined the role of HMG-CoA reductase (HMGCR) during porcine circovirus 2 (PCV2) infection. The results demonstrated that levels of endogenous HMGCR were not significantly different in PCV2-infected cells and mock-infected cells. However, the level of phosphorylated HMGCR, an inactivated form of HMGCR, was increased in PCV2-infected cells. Furthermore, HMGCR was upregulated by overexpression, silenced by siRNA or inactivated using its dominant-negative form in PK-15 cells. The results showed that PCV2 infection was inhibited by HMGCR overexpression, whereas it was significantly increased in HMGCR-silenced cells and HMGCR inhibitor-treated cells. Moreover, there was a robust apoptotic response at 48 h post-infection (p.i.) in HMGCR-inactivated cells, and this response was significantly greater than that observed in PK-15 cells. A modest apoptotic response was also observed in HMGCR-silenced cells. Caspase-3 activity was also analysed in PCV2-infected cells at 48 h p.i. As expected, caspase-3 activity was significantly increased in HMGCR-inactivated and -silenced cells compared with PK-15 cells. PCV2 replication was dose-dependently increased in HMGCR-inactivated cells when treated with increasing amounts of caspase-3 inhibitor. Altogether, HMGCR was negatively associated with PCV2 infection and PCV2-induced apoptotic cell death. These data demonstrated that HMGCR can be used as a candidate target for PCV2 disease control and antivirus research. Furthermore, the cells generated in this study can be used to evaluate the potential effects of HMGCR on PCV2 replication.
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Green electrospun pantothenic acid/silk fibroin composite nanofibers: fabrication, characterization and biological activity.
Colloids Surf B Biointerfaces
PUBLISHED: 03-18-2014
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Silk fibroin (SF) from Bombyx mori has many established excellent properties and has found various applications in the biomedical field. However, some abilities or capacities of SF still need improving to meet the need for using practically. Indeed, diverse SF-based composite biomaterials have been developed. Here we report the feasibility of fabricating pantothenic acid (vitamin B5, VB5)-reinforcing SF nanofibrous matrices for biomedical applications through green electrospinning. Results demonstrated the successful loading of D-pantothenic acid hemicalcium salt (VB5-hs) into resulting composite nanofibers. The introduction of VB5-hs did not alter the smooth ribbon-like morphology and the silk I structure of SF, but significantly decreased the mean width of SF fibers. SF conformation transformed into ?-sheet from random coil when composite nanofibrous matrices were exposed to 75% (v/v) ethanol vapor. Furthermore, nanofibers still remained good morphology after being soaked in water environment for five days. Interestingly, as-prepared composite nanofibrous matrices supported a higher level of cell viability, especially in a long culture period and significantly assisted skin cells to survive under oxidative stress compared with pure SF nanofibrous matrices. These findings provide a basis for further extending the application of SF in the biomedical field, especially in the personal skin-care field.
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The expression of miR-21 and miR-375 predict prognosis of esophageal cancer.
Biochem. Biophys. Res. Commun.
PUBLISHED: 03-11-2014
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MicroRNA is a class of small, well-conserved, non-coding RNAs, and could play a potential role as diagnostic and prognostic biomarkers of esophageal cancers. We aimed to review comprehensively the evidence of microRNA as prognostic biomarkers in esophageal cancers.
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Is fibrin sealant effective and safe in total knee arthroplasty? A meta-analysis of randomized trials.
J Orthop Surg Res
PUBLISHED: 03-10-2014
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The objective of this study was to evaluate the efficacy and safety of fibrin sealant in patients following total knee arthroplasty (TKA). A comprehensive literature search of the electronic databases PubMed, MEDLINE, Web of Science, and Cochrane Library for published randomized controlled trials (RCTs) was undertaken. The evidence base was critically appraised using a tool from the Cochrane Bone, Joint and Muscle Trauma Group. Eight RCTs involving 641 patients were included. The use of fibrin sealant significantly reduced postoperative drainage (weighted mean difference (WMD) -346, 95% confidence interval (CI) -496.29 to -197.54, P?
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Genomic imprinting analysis of Igf2/H19 in porcine cloned fetuses using parthenogenetic somatic cells as nuclear donors.
Biotechnol. Lett.
PUBLISHED: 02-28-2014
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To gain insight into parthenogenesis in pigs, we report for the first time that using parthenogenetic somatic cells as nuclear donors (PSCNT), the porcine parthenogenetic fetus can develop to gestational day 39. Weight and morphological analysis revealed that PSCNT fetuses were smaller and developmentally retarded when compared to normally fertilized controls. Quantitative gene expression analysis indicated that in PSCNT fetuses, H19 was over-expressed, whereas Igf2 was significantly reduced (p < 0.05) compared with their controls. In addition, bisulfite-sequencing PCR results demonstrated that H19 differentially DNA methylated regions (DMRs) were hypomethylated in PSCNT fetuses, while Igf2 DMRs were hypermethylated in both PSCNT and control fetuses. Our results suggest that extended development of the porcine parthenogenetic fetus can be accomplished using PSCNT and that abnormal DNA methylation of H19 DMRs might contribute to the critical barrier of parthenogenesis in pigs.
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Identification of dirty necrosis in colorectal carcinoma based on multiphoton microscopy.
J Biomed Opt
PUBLISHED: 02-26-2014
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Dirty necrosis within glandular lumina is often considered as a characteristic of colorectal carcinomas (CRCs) that is a diagnostically useful feature of CRCs with DNA microsatellite instability (MSI). Multiphoton microscopy (MPM), which is based on the second-harmonic generation and two-photon excited fluorescence signals, was used to identify dirty necrosis. Our results demonstrated that MPM has the ability to exhibit the microstructure of dirty necrosis and the signal intensity as well as an emission spectrum that can help to differentiate dirty necrosis from cancer cells. These findings indicate that MPM may be helpful in distinguishing MSI colorectal carcinoma via the identification of dirty necrosis.
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Protein Phosphatase 1 (PP1) and Casein Kinase II (CK2) regulate Ikaros-mediated repression of TdT in thymocytes and T-cell leukemia.
Pediatr Blood Cancer
PUBLISHED: 02-25-2014
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Ikaros is a DNA-binding protein that acts as master-regulator of hematopoiesis and a tumor suppressor. In thymocytes and T-cell leukemia, Ikaros negatively regulates transcription of terminal deoxynucleotide transferase (TdT), a key protein in lymphocyte differentiation. The signaling pathways that regulate Ikaros-mediated repression of TdT are unknown. Our previous work identified Casein Kinase II (CK2) and Protein Phosphatase 1 (PP1) as regulators of Ikaros DNA binding activity. Here, we investigated the role of PP1 and CK2 in regulating Ikaros-mediated control of TdT expression.
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Elevated expression of vascular endothelial growth factor (VEGF) 120 in parthenogenetic porcine placentas.
Biotechnol. Lett.
PUBLISHED: 02-21-2014
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Most mammalian parthenogenetic embryos are unable to develop to term due to placental defects, potentially caused by decreased vasculogenesis and angiogenesis of the parthenogenetic placenta. Here we have compared the expression status of vascular endothelial growth factor (VEGF) and angiopoietin family members between normally developing and parthenogenetic porcine placentas. The result showed significantly reduced expression of these genes but elevated expression of VEGF 120 in the parthenogenetic porcine placenta (p < 0.05). We postulate that the abnormal expression levels of VEGF and angiopoietin family members and, especially, the elevated expression of VEGF 120 observed in parthenogenetic porcine placentas are related to the early miscarriage of parthenogenetic embryos in pigs.
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Construction and expression of mutagenesis strain of aroG gene from Escherichia coli K-12.
Int. J. Biol. Macromol.
PUBLISHED: 02-17-2014
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3-Deoxy-d-arabino-heptulonate-7-phosphate (DAHP) synthase is one of the key enzymes, which catalyzes the first step in the aromatic amino acid biosynthetic pathway and yields the three amino acids tyrosine (Tyr), tryptophan (Typ), and phenylalanine (Phe). In Escherichia coli (E. coli), three differently regulated DAHP synthases carry out the first regulated step in the aromatic amino acid biosynthetic pathway. The three DAHP synthases encoded by the genes aroG, aroF, and aroH are inhibited by phenylalanine, tyrosine and tryptophan, respectively. In this work, the aroG gene was cloned and mutated by site-directed mutagenesis using overlap extension PCR (SOE-PCR) technique. The feedback-resistant DAHP synthase encoded by aroG was achieved by replacing the residue Pro150 of aroG with Leu as to increase net carbon flow down the common pathway. SDS-PAGE and Western blots were used to assess the protein expression level of aroGM which showed the strain harboring the mutated aroGM150 gene achieving over-expression compared to the strain containing an empty plasmid pET-28b((+)).
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Image based weighted center of proximity versus directly measured knee contact location during simulated gait.
J Biomech
PUBLISHED: 02-13-2014
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To understand the mechanical consequences of knee injury requires a detailed analysis of the effect of that injury on joint contact mechanics during activities of daily living. Three-dimensional (3D) knee joint geometric models have been combined with knee joint kinematics to dynamically estimate the location of joint contact during physiological activities-using a weighted center of proximity (WCoP) method. However, the relationship between the estimated WCoP and the actual location of contact has not been defined. The objective of this study was to assess the relationship between knee joint contact location as estimated using the image-based WCoP method, and a directly measured weighted center of contact (WCoC) method during simulated walking. To achieve this goal, we created knee specific models of six human cadaveric knees from magnetic resonance imaging. All knees were then subjected to physiological loads on a knee simulator intended to mimic gait. Knee joint motion was captured using a motion capture system. Knee joint contact stresses were synchronously recorded using a thin electronic sensor throughout gait, and used to compute WCoC for the medial and lateral plateaus of each knee. WCoP was calculated by combining knee kinematics with the MRI-based knee specific model. Both metrics were compared throughout gait using linear regression. The anteroposterior (AP) location of WCoP was significantly correlated with that of WCoC on both tibial plateaus in all specimens (p<0.01, 95% confidence interval of Pearson?s coefficient r>0), but the correlation was not significant in the mediolateral (ML) direction for 4/6 knees (p>0.05). Our study demonstrates that while the location of joint contact obtained from 3D knee joint contact model, using the WCoP method, is significantly correlated with the location of actual contact stresses in the AP direction, that relationship is less certain in the ML direction.
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Risk factors of radiation-induced acute esophagitis in non-small cell lung cancer patients treated with concomitant chemoradiotherapy.
Radiat Oncol
PUBLISHED: 02-13-2014
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To analyze the clinical and dosimetric risk factors of acute esophagitis (AE) in non-small-cell lung cancer (NSCLC) patients treated with concomitant chemoradiotherapy.
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Berberine regulates AMP-activated protein kinase signaling pathways and inhibits colon tumorigenesis in mice.
Mol. Carcinog.
PUBLISHED: 02-12-2014
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Colorectal cancer, a leading cause of cancer death, has been linked to inflammation and obesity. Berberine, an isoquinoline alkaloid, possesses anti-inflammatory, anti-diabetes and anti-tumor properties. In the azoxymethane initiated and dextran sulfate sodium (AOM/DSS) promoted colorectal carcinogenesis mouse model, berberine treated mice showed a 60% reduction in tumor number (P?=?0.009), a 48% reduction in tumors <2?mm, (P?=?0.05); 94% reduction in tumors 2-4?mm, (P?=?0.001), and 100% reduction in tumors >4?mm (P?=?0.02) compared to vehicle treated mice. Berberine also decreased AOM/DSS induced Ki-67 and COX-2 expression. In vitro analysis showed that in addition to its anti-proliferation activity, berberine also induced apoptosis in colorectal cancer cell lines. Berberine activated AMP-activated protein kinase (AMPK), a major regulator of metabolic pathways, and inhibited mammalian target of rapamycin (mTOR), a downstream target of AMPK. Furthermore, 4E-binding protein-1 and p70 ribosomal S6 kinases, downstream targets of mTOR, were down regulated by berberine treatment. Berberine did not affect Liver kinase B1 (LKB1) activity or the mitogen-activated protein kinase pathway. Berberine inhibited Nuclear Factor kappa-B (NF-?B) activity, reduced the expression of cyclin D1 and survivin, induced phosphorylation of p53 and increased caspase-3 cleavage in vitro. Berberine inhibition of mTOR activity and p53 phosphorylation was found to be AMPK dependent, while inhibition NF-?B was AMPK independent. In vivo, berberine also activated AMPK, inhibited mTOR and p65 phosphorylation and activated caspase-3 cleavage. Our data suggests that berberine suppresses colon epithelial proliferation and tumorigenesis via AMPK dependent inhibition of mTOR activity and AMPK independent inhibition of NF-?B. © 2014 Wiley Periodicals, Inc.
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Long-term outcome of sensorineural hearing loss in nasopharyngeal carcinoma patients: comparison between treatment with radiotherapy alone and chemoradiotherapy.
Cell Biochem. Biophys.
PUBLISHED: 02-11-2014
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The purpose of this study is to assess the long-term effect of sensorineural hearing loss (SNHL) resulted from radiotherapy (RT) alone versus chemoradiotherapy in nasopharyngeal carcinoma patients (NPC). Seventy-two patients initially diagnosed with NPC were enrolled from Shandong Tumor Hospital between March 2003 and May 2007. They were assigned into two groups: RT alone and chemoradiotherapy according to the different treatment regimens. Intensity-modulated radiation therapy was applied for both groups, concurrent and adjuvant cisplatin were administered for chemoradiotherapy group additionally. Hearing threshold test was performed at various time periods after completion of RT. Mean radiation dose to the cochlea in each ear was calculated to determine the correlation between cochlear dose and SNHL. We found that the hearing loss is more severe in the chemoradiotherapy group compared with RT group, from completion of RT up to the 5 years of follow-up period. This is especially obvious in the high frequency range. Hearing level is seriously damaged when cochlea dose exceeds 46 GY. We concluded that concurrent/adjuvant chemotherapy plus RT aggravates SNHL in NPC patients than RT alone and thus inner ear tissue tolerance should be redefined in those patients.
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Randomized, placebo controlled and double-blind trials of efficacy and safety of adalimumab for treating ankylosing spondylitis: a meta-analysis.
Int J Rheum Dis
PUBLISHED: 02-08-2014
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Adalimumab is a fully human, anti-TNF monoclonal antibody of proven efficacy and safety in the treatment of the signs, symptoms and functional disability of ankylosing spondylitis (AS). A systematic review and meta-analysis was performed to assess the efficacy and safety of adalimumab treatment, relative to a placebo, in adult patients with AS. In the efficacy meta-analysis, significantly more patients in the adalimumab group achieved Assessment in AS International Working Group (ASAS)20 and Bath AS Disease Activity Index (BASDAI)50 compared with patients in the placebo group. Patients in the adalimumab group also showed significant improvement in BASDAI and health-related quality of life. With regard to adverse events, any adverse events and injection-site reaction were significantly higher in the adalimumab group compared with the control group. This meta-analysis shows a higher efficacy of adalimumab relative to placebo, but clinicians should be careful regarding adverse events in adalimumab-treated patients.
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Genetic variants in inducible nitric oxide synthase gene are associated with the risk of radiation-induced lung injury in lung cancer patients receiving definitive thoracic radiation.
Radiother Oncol
PUBLISHED: 02-02-2014
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Nitric oxide (NO), mainly synthesized by inducible nitric oxide synthase (NOS2) in pathological conditions, plays an important role in cytotoxicity, inflammation and fibrosis. Elevations in exhaled NO after thoracic radiation have been reported to predict radiation-induced lung injury (RILI). This study examined whether genetic variations in NOS2 gene is associated with the risk of RILI.
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The transcription factor IRF8 activates integrin-mediated TGF-? signaling and promotes neuroinflammation.
Immunity
PUBLISHED: 01-30-2014
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Recent epidemiological studies have identified interferon regulatory factor 8 (IRF8) as a susceptibility factor for multiple sclerosis (MS). However, how IRF8 influences the neuroinflammatory disease has remained unknown. By studying the role of IRF8 in experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, we found that Irf8(-/-) mice are resistant to EAE. Furthermore, expression of IRF8 in antigen-presenting cells (APCs, such as macrophages, dendritic cells, and microglia), but not in T cells, facilitated disease onset and progression through multiple pathways. IRF8 enhanced ?v?8 integrin expression in APCs and activated TGF-? signaling leading to T helper 17 (Th17) cell differentiation. IRF8 induced a cytokine milieu that favored growth and maintenance of Th1 and Th17 cells, by stimulating interleukin-12 (IL-12) and IL-23 production, but inhibiting IL-27 during EAE. Finally, IRF8 activated microglia and exacerbated neuroinflammation. Together, this work provides mechanistic bases by which IRF8 contributes to the pathogenesis of MS.
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[Tumor targeting efficacy of a novel PET radiotracer (1)8F-AlF-NOTA-PRGD2 in mice].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 01-28-2014
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To investigate the tumor targeting efficacy of (18)F-AlF-NOTA-PRGD2, a novel radiotracer of Arginine-glycine-aspartic acid (RGD) peptides.
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Risk factors for hepatitis B virus reactivation after conformal radiotherapy in patients with hepatocellular carcinoma.
Cancer Sci.
PUBLISHED: 01-22-2014
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This study investigated whether conformal radiotherapy affects hepatitis B virus (HBV) reactivation, and the risk factors for HBV reactivation in patients with HBV-related hepatocellular carcinoma (HCC). Sixty-nine patients with HCC were included in this retrospective study. Before radiotherapy (RT), all patients underwent imaging examinations and some baseline examinations, including CBC, liver function test, renal function test, ?-fetoprotein level, hepatitis B (HB) surface antigen, HB surface Ab, HB e antigen, HB e Ab, and serum HBV DNA quantification. During the period of RT and at least 16 weeks after the end of RT, CBCs were carried out weekly and the other tests were monitored monthly or more frequently if necessary. The clinical features and dosimetric parameters of RT were recorded. Univariate and multivariate logistic regression algorithms were used to analyze the risk factors of HBV reactivation. The incidence of complications in the study population was as follows: radiation-induced liver disease, 17.4%; HBV reactivation, 24.6%; and HBV reactivation-induced hepatitis, 21.7%. The HBV DNA level and dose volume parameters including normal liver volume, V20, and mean dose were associated with HBV reactivation. There was a relatively high incidence of HBV reactivation in HCC patients after the end of conformal RT. The serum HBV DNA level and some dosimetric parameters related to normal liver, including normal liver volume, V20, and mean dose, were the prognosis factors of HBV reactivation and should be carefully considered before conformal RT.
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Expression, purification and antibody preparation using different constructs of PCV2 capsid protein.
Int. J. Biol. Macromol.
PUBLISHED: 01-20-2014
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Capsid protein (Cap) of porcine circovirus 2 (PCV2) contained critical epitopes for inducing a protective immune response. Here, different fragments of PCV2 Cap protein were cloned, expressed, purified and used to raise polyclonal antibodies. The result showed the recombinant plasmids expressed efficiently in the prokaryotic system. Western blot and ELISA showed the recombinant protein had antigenicity and immunogenicity. Furthermore, efficiency of different constructs to produce antibody against PCV2 was compared. Reactivity and specificity of the polyclonal antibody were characterized by Western blot and indirect immunofluorescent assays. The results indicated that polyclonal antiserum prepared from protein ?Cap17-233 had better reactivity and specificity against PCV2 in comparison to that of protein ?Cap51-233 and the inactivated vaccine. These results will contribute to further studies focusing on the gene and vaccine development against PCV2.
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Effectiveness, medication patterns, and adverse events of traditional chinese herbal patches for osteoarthritis: a systematic review.
Evid Based Complement Alternat Med
PUBLISHED: 01-14-2014
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Objective. The aim of this study is to systematically evaluate the evidence whether traditional Chinese herbal patches (TCHPs) for osteoarthritis (OA) are effective and safe and analyze their medication patterns. Methods. A systematic literature search was performed using all the possible Medical Subject Headings (MeSH) and keywords from January 1979 to July 2013. Both randomized controlled trials (RCTs) and observational studies were included. Estimated effects were analyzed using mean difference (MD) or relative risk (RR) with 95% confidence intervals (CI) and meta-analysis. Results. 86 kinds of TCHPs were identified. RCTs and controlled clinical trials (CCTs) which were mostly of low quality favored TCHPs for local pain and dysfunction relief. TCHPs, compared with diclofenac ointment, had significant effects on global effectiveness rate (RR = 0.50; 95% CI (0.29, 0.87)). Components of formulae were mainly based on the compounds "Xiao Huo Luo Dan" (Minor collateral-freeing pill) and "Du Huo Ji Sheng Tang" (Angelicae Pubescentis and Loranthi decoction). Ten kinds of adverse events (AEs), mainly consisting of itching and/or local skin rashes, were identified after 3-4 weeks of follow-up. Conclusions. TCHPs have certain evidence in improving global effectiveness rate for OA; however, more rigorous studies are warranted to support their use.
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Sequence-specific inhibition of microRNA via CRISPR/CRISPRi system.
Sci Rep
PUBLISHED: 01-13-2014
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Here, we report a convenient and efficient miRNA inhibition strategy employing the CRISPR system. Using specifically designed gRNAs, miRNA gene has been cut at a single site by Cas9, resulting in knockdown of the miRNA in murine cells. Using a modified CRISPR interference system (CRISPRi), inactive Cas9 can reversibly prevent the expression of both monocistronic miRNAs and polycistronic miRNA clusters. Furthermore, CRISPR/CRISPRi is also capable of suppressing genes in porcine cells.
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Spatiotemporal control of porcine p65RHD expression by advanced Tet-On system in PIEC cells helps regulate NF?B activity.
Mol. Biol. Rep.
PUBLISHED: 01-03-2014
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NF?B transcription activation leads to malfunction of endothelial cells, which is the main reason for pig xenograft rejection. Overexpression of a dominant negative mutant of porcine NF?B p65 (pp65RHD) could inhibit NF?B activation in endothelial cells. This study presents an advanced tetracycline-regulated system for pp65RHD spatiotemporal expression in porcine iliac endothelial cell line. In this system, an endothelial specific promoter ICAM-2 is used to improve pTet-On and internal ribosome entry site as well as enhanced green fluorescent protein (EGFP) elements are used to facilitate the result observation in pTRE-Tight. Through transfection and drug selection, we obtained 7 single cell clones containing the advanced Tet-On system, in which pp65RHD expression is under tight regulated by doxycycline and can be visualized easily through EGFP. The distribution of induced pp65RHD was verified by immunocytochemical assays test. Then, NF?B activity was tested. Luciferase reporter assays showed that NF?B activity in two clones was influenced by the Dox-induced pp65RHD expression, but other clones weren't influenced. Therefore, we picked up 2 cell clones from the uninfluenced clones for further investigation by immunocytochemical assays and RT-PCR detection. The final results supported the overexpression of pp65RHD in one clone could successfully inhibit NF?B activity. The success of pp65RHD spatiotemporal expression system is helpful to regulate NF?B activity and conquer cell-mediated immunity and could be used for preparation of transgenic pig, contributing to xenotransplantation.
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Production of transgenic pigs over-expressing the antiviral gene Mx1.
Cell Regen (Lond)
PUBLISHED: 01-01-2014
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The myxovirus resistance gene (Mx1) has a broad spectrum of antiviral activities. It is therefore an interesting candidate gene to improve disease resistance in farm animals. In this study, we report the use of somatic cell nuclear transfer (SCNT) to produce transgenic pigs over-expressing the Mx1 gene. These transgenic pigs express approximately 15-25 times more Mx1 mRNA than non-transgenic pigs, and the protein level of Mx1 was also markedly enhanced. We challenged fibroblast cells isolated from the ear skin of transgenic and control pigs with influenza A virus and classical swine fever virus (CFSV). Indirect immunofluorescence assay (IFA) revealed a profound decrease of influenza A proliferation in Mx1 transgenic cells. Growth kinetics showed an approximately 10-fold reduction of viral copies in the transgenic cells compared to non-transgenic controls. Additionally, we found that the Mx1 transgenic cells were more resistant to CSFV infection in comparison to non-transgenic cells. These results demonstrate that the Mx1 transgene can protect against viral infection in cells of transgenic pigs and indicate that the Mx1 transgene can be harnessed to develop disease-resistant pigs.
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Katanin p60 promotes neurite growth and collateral formation in the hippocampus.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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This study aimed to investigate the effect of Katanin p60 on the neurite growth and collateral formation in the hippocampus.
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B-myb is a gene implicated in cell cycle and proliferation of breast cancer.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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B-myb belongs to the myb family of transcription factors that include A-myb and c-myb. While A-myb and c-myb are tissue-specific, B-myb is broadly expressed in rapidly dividing cells of developing adult mammals. Results of our study showed that increased B-myb expression of was associated with the progression of breast cancer and that B-myb protein levels were signi?cantly elevated in matched metastases. High B-myb levels also predict shorter overall survival of breast cancer patients. Moreover, B-myb stimulated transcription of target genes that promoted entry into the S and M-phases of the cell cycle, cell proliferation, migration and invasion in breast cancer. Taken together, our results strongly demonstrated that B-myb had a critical role in both cell cycle progression and tumorigenesis, and might serve as a novel potential target in the diagnosis and/or treatment of human breast cancer.
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Primary microcephaly gene MCPH1 shows a novel molecular biomarker of human renal carcinoma and is regulated by miR-27a.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Microcephalin 1 (MCPH1) gene, initially identified as an hTERT repressor, result in two autosomal recessive disorders: primary microcephaly and premature chromosome condensation syndrome. Recently, several studies have found that MCPH1 has also been shown to be downregulated in several different types of human cancers, suggesting that it could also function as a tumor suppressor gene and a novel molecular biomarker of human cancers. To investigate its potential role in the human renal carcinoma progression, we evaluated the expression of protein MCPH1 in 188 renal cancer and 20 normal renal tissues from 188 patients with renal cancer and 20 healthy persons by immunohistochemistry. Positive MCPH1 staining was found in all normal renal samples and partly in cancerous tissues. But MCPH1-positive cells resulted significantly lower in renal carcinoma tissues compared with normal tissues. We further observed that overexpression of MCPH1 decreased cellular proliferation, cell migration and invasion and induced cell apoptosis, indicating it is tumor suppressor. Using bioinformatics approaches and luciferase reporter assay, we showed that the 3'-UTR of MCPH1 harbors two non-overlapping functional seed regions for miR-27 which negatively regulated its level. The expression level of miR-27a negatively correlated with the MCPH1 protein level in renal cancer. Our study indicates for the first time that, in addition to its role in brain development, MCPH1 also functions as a tumor suppressor gene and is directly regulated by miR-27a.
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CRMP-5 interacts with tubulin to promote growth cone development in neurons.
Int J Clin Exp Med
PUBLISHED: 01-01-2014
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Collapsin response mediator proteins (CRMPs) have been reported to control axonal guidance during neuronal development and degeneration. Among these proteins, CRMP-5 has been indicated to play an important role in growth cone development. However, the mechanisms underlying the linkage between growth cone development and the cytoskeleton remain to be elucidated. Here, we report that CRMP-5 interacts with tubulin to mediate growth cone development in cultured hippocampal neurons. We found that CRMP-5 physically interacted with tubulin in the growth cones of developing neurons. CRMP-5 colocalized with tubulin in lamellipodia in HEK293 cells and in the growth cones of cultured hippocampal neurons. Genetic silencing of CRMP-5 using RNA interference led to abnormal growth cone morphology in neurons. Overexpression of CRMP-5 led to significantly increased filopodial formation and enlarged growth cones. These results suggest that CRMP-5 interacts with tubulin to regulate growth cone dynamics, thus complying with the restrictive intracellular guidance cues.
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Efficacy and Safety of Accelerated Partial Breast Irradiation after Breast-conserving Surgery: A Meta-analysis of Published Comparative Studies.
Breast J
PUBLISHED: 12-26-2013
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To compare the treatment outcomes between accelerated partial breast irradiation (APBI) and conventional whole-breast irradiation (WBI) and to explore the efficacy and safety of APBI as an adjuvant treatment for early-stage breast cancer who received breast-conserving therapy. Eligible studies were identified on Medline, Embase, and the Cochrane Library updated to July 10, 2012. Comparative studies were considered for inclusion. Analyses were carried out using Stata software. Eleven comparative studies with a total of 7,097 patients were included. The meta-analysis showed that there were no statistically significant differences between group APBI and group WBI associated with the supraclavicular failure, distant metastasis, overall survival, and disease-free survival, while local recurrence (LR) and axillary failure (AF) increased in group APBI. The sensitivity analysis indicated that both the LR and AF were not statistically significant difference between the two groups. In the subgroup analysis, LR was statistically significantly higher in group APBI for patients with the age <60, large tumor size, and unknown margin status. APBI is a safe treatment modality and could become a potential option for the delivery of adjuvant radiation therapy in patients receiving breast-conserving therapy, especially for the suitable group that was classified by the American Society of Radiation Oncology Consensus Panel.
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Langerhans cells are generated by two distinct PU.1-dependent transcriptional networks.
J. Exp. Med.
PUBLISHED: 11-18-2013
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Langerhans cells (LCs) are the unique dendritic cells found in the epidermis. While a great deal of attention has focused on defining the developmental origins of LCs, reports addressing the transcriptional network ruling their differentiation remain sparse. We addressed the function of a group of key DC transcription factors-PU.1, ID2, IRF4, and IRF8-in the establishment of the LC network. We show that although steady-state LC homeostasis depends on PU.1 and ID2, the latter is dispensable for bone marrow-derived LCs. PU.1 controls LC differentiation by regulating the expression of the critical TGF-? responsive transcription factor RUNX3. PU.1 directly binds to the Runx3 regulatory elements in a TGF-?-dependent manner, whereas ectopic expression of RUNX3 rescued LC differentiation in the absence of PU.1 and promoted LC differentiation from PU.1-sufficient progenitors. These findings highlight the dual molecular network underlying LC differentiation, and show the central role of PU.1 in these processes.
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Efficiency of porcine somatic cell nuclear transfer - a retrospective study of factors related to embryo recipient and embryos transferred.
Biol Open
PUBLISHED: 11-15-2013
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The successful generation of pigs via somatic cell nuclear transfer depends on reducing risk factors in several aspects. To provide an overview of some influencing factors related to embryo transfer, the follow-up data related to cloned pig production collected in our laboratory was examined. (i) Spring showed a higher full-term pregnancy rate compared with winter (33.6% vs 18.6%, P?=?0.006). Furthermore, a regression equation can be drawn between full-term pregnancy numbers and pregnancy numbers in different months (y?=?0.692x-3.326). (ii) There were no significant differences detected in the number of transferred embryos between surrogate sows exhibiting full-term development compared to those that did not. (iii) Non-ovulating surrogate sows presented a higher percentage of full-term pregnancies compared with ovulating sows (32.0% vs 17.5%, P?=?0.004; respectively). (iv) Abortion was most likely to take place between Day 27 to Day 34. (v) Based on Life Table Survival Analysis, delivery in normally fertilized and surrogate sows is expected to be completed before Day 117 or Day 125, respectively. Additionally, the length of pregnancy in surrogate sows was negatively correlated with the average litter size, which was not found for normally fertilized sows. In conclusion, performing embryo transfer in appropriate seasons, improving the quality of embryos transferred, optimizing the timing of embryo transfer, limiting the occurrence of abortion, combined with ameliorating the management of delivery, is expected to result in the harvest of a great number of surviving cloned piglets.
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Targeted Deletion of the Gene Encoding the La Autoantigen (Sjogrens Syndrome Antigen B) in B Cells or the Frontal Brain Causes Extensive Tissue Loss.
Mol. Cell. Biol.
PUBLISHED: 11-04-2013
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La antigen (Sjögrens syndrome antigen B) is a phosphoprotein associated with nascent precursor tRNAs and other RNAs, and it is targeted by autoantibodies in patients with Sjögrens syndrome, systemic lupus erythematosus, and neonatal lupus. Increased levels of La are associated with leukemias and other cancers, and various viruses usurp La to promote their replication. Yeast cells (Saccharomyces cerevisiae and Schizosaccharomyces pombe) genetically depleted of La grow and proliferate, whereas deletion from mice causes early embryonic lethality, raising the question of whether La is required by mammalian cells generally or only to surpass a developmental stage. We developed a conditional La allele and used it in mice that express Cre recombinase in either B cell progenitors or the forebrain. B cell Mb1(Cre) La-deleted mice produce no B cells. Consistent with ?CamKII Cre, which induces deletion in hippocampal CA1 cells in the third postnatal week and later throughout the neocortex, brains develop normally in La-deleted mice until ?5 weeks and then lose a large amount of forebrain cells and mass, with evidence of altered pre-tRNA processing. The data indicate that La is required not only in proliferating cells but also in nondividing postmitotic cells. Thus, La is essential in different cell types and required for normal development of various tissue types.
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Over-expression of microRNA-494 Up-regulates hypoxia-inducible factor-1 alpha expression via PI3K/Akt pathway and protects against hypoxia-induced apoptosis.
J. Biomed. Sci.
PUBLISHED: 09-11-2013
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Hypoxia-inducible factor-1 alpha (HIF-1alpha) is one of the key regulators of hypoxia/ischemia. MicroRNA-494 (miR-494) had cardioprotective effects against ischemia/reperfusion (I/R)-induced injury, but its functional relationship with HIF-1alpha was unknown. This study was undertaken to determine if miR-494 was involved in the induction of HIF-1alpha.
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Multipotent mesenchymal stem cells from human subacromial bursa: potential for cell based tendon tissue engineering.
Tissue Eng Part A
PUBLISHED: 08-21-2013
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Rotator cuff injuries are a common clinical problem either as a result of overuse or aging. Biological approaches to tendon repair that involve use of scaffolding materials or cell-based approaches are currently being investigated. The cell-based approaches are focused on applying multipotent mesenchymal stem cells (MSCs) mostly harvested from bone marrow. In the present study, we focused on characterizing cells harvested from tissues associated with rotator cuff tendons based on an assumption that these cells would be more appropriate for tendon repair. We isolated MSCs from bursa tissue associated with rotator cuff tendons and characterized them for multilineage differentiation in vitro and in vivo. Human bursa was obtained from patients undergoing rotator cuff surgery and cells within were isolated using collagenase and dispase digestion. The cells isolated from the tissues were characterized for osteoblastic, adipogenic, chondrogenic, and tenogenic differentiation in vitro and in vivo. The results showed that the cells isolated from bursa tissue exhibited MSCs characteristics as evidenced by the expression of putative cell surface markers attributed to MSCs. The cells exhibited high proliferative capacity and differentiated toward cells of mesenchymal lineages with high efficiency. Bursa-derived cells expressed markers of tenocytes when treated with bone morphogenetic protein-12 (BMP-12) and assumed aligned morphology in culture. Bursa cells pretreated with BMP-12 and seeded in ceramic scaffolds formed extensive bone, as well as tendon-like tissue in vivo. Bone formation was demonstrated by histological analysis and immunofluorescence for DMP-1 in tissue sections made from the scaffolds seeded with the cells. Tendon-like tissue formed in vivo consisted of parallel collagen fibres typical of tendon tissues. Bursa-derived cells also formed a fibrocartilagenous tissue in the ceramic scaffolds. Taken together, the results demonstrate a new source of MSCs with a high potential for application in tendon repair.
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Object matching using a locally affine invariant and linear programming techniques.
IEEE Trans Pattern Anal Mach Intell
PUBLISHED: 08-14-2013
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In this paper, we introduce a new matching method based on a novel locally affine-invariant geometric constraint and linear programming techniques. To model and solve the matching problem in a linear programming formulation, all geometric constraints should be able to be exactly or approximately reformulated into a linear form. This is a major difficulty for this kind of matching algorithm. We propose a novel locally affine-invariant constraint which can be exactly linearized and requires a lot fewer auxiliary variables than other linear programming-based methods do. The key idea behind it is that each point in the template point set can be exactly represented by an affine combination of its neighboring points, whose weights can be solved easily by least squares. Errors of reconstructing each matched point using such weights are used to penalize the disagreement of geometric relationships between the template points and the matched points. The resulting overall objective function can be solved efficiently by linear programming techniques. Our experimental results on both rigid and nonrigid object matching show the effectiveness of the proposed algorithm.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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

Video X seems to be unrelated to Abstract Y...

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