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Find video protocols related to scientific articles indexed in Pubmed.
Reductive dechlorination of BCl3 for efficient ammonia borane regeneration.
Dalton Trans
PUBLISHED: 11-20-2014
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This paper reports a complete ammonia borane (AB) regeneration process in which Bu3SnH was utilized as a reductant for the reductive dechlorination of BCl3, and Et2PhN was selected as a 'helper ligand' to generate Et2PhN·BH3, which gives rise to a high yield of AB by a base-exchange reaction at ambient temperature.
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Super-resolution radially polarized-light pupil-filtering confocal sensing technology.
Appl Opt
PUBLISHED: 11-18-2014
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Radially polarized beams can be focused to a tighter spot in the focal plane with a high numerical-aperture objective when combined with an optimally designed pupil filter. Based on the unique characters, a novel super-resolution radially polarized-light pupil-filtering confocal sensing technology (SRPCST) is proposed, and a sensor based on SRPCST is developed. By using a radially polarized beam and pupil-filtering technology, SRPCST can effectively improve its lateral resolution. In SRPCST a strong longitudinal field component can be generated in the focal plane by focusing a radially polarized light with a high numerical-aperture objective. Pupil-filtering technology will modify the pupil function of the optical system by optimally designing the parameters of pupil filter to higher resolution. Theoretical analyses and packaged SRPCST sensor experiments indicate that the lateral resolution of SRPCST can be improved by 15.23% and 32.12% through super-resolution image restoration compared with confocal microscopy under the same conditions.
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Three-step method for systematic lymphadenectomy in gastric cancer surgery using the 'curettage and aspiration dissection technique' with Peng's multifunctional operative dissector.
World J Surg Oncol
PUBLISHED: 10-01-2014
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Gastric cancer is one of the most common malignancies and is a leading cause of cancer death worldwide. Surgery is the most effective and successful method of treatment for gastric cancer, and systematic lymph node (LN) dissection is unquestionably the most effective procedure for treating LN metastases of gastric cancer. Systematic lymphadenectomy is the most important part of curative resection, but lymphadenectomy is also the most difficult procedure in gastric cancer surgery. The aim of this study is to report our three-step method for lymphadenectomy in gastric cancer.
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RNA interference in the progress of gastric cancer.
Pak J Pharm Sci
PUBLISHED: 09-29-2014
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Gastric cancer is one of common malignant tumors. The development of molecular biology and genetics prompts people to regulate tumor cell regulation from the gene level, and seeks method to the new tumor therapy. RNA interference (which is also called RNAi) is a technology of double stranded RNAexogenous or dsRNA into cells, therefore this thereby inhibits the expression function of corresponding target gene. This paper summarizes the development process and the mechanism of RNAi technology, outlines the progress of experimental gastric cancer of the current RNAi technology, which shows that this technology can directly or indirectly inhibit tumor, and reduce the drug resistance of tumor cells. With the gradual improvement of RNAi technology, it will become a new direction for gene therapy of gastric cancer.
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Tetrandrine induces apoptosis in gallbladder carcinoma in vitro.
Int J Clin Pharmacol Ther
PUBLISHED: 09-29-2014
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The aims of this study were to observe the apoptosis effects of tetrandrine on human gallbladder carcinoma cell line (SGC-996), and to explore its related mechanism.
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Sub-bandgap transverse frequency conversion in semiconductor nano-waveguides.
Nanoscale
PUBLISHED: 09-10-2014
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Transverse frequency conversion in the sub-bandgap spectral region is investigated in semiconductor nanowires and nanoribbons using CW lasers with a pump power less than 1 mW. It is found that the properties of the emissions are strongly dependent on the cross-sectional geometries and the surrounding media of nano-waveguides. The polarization is higher in nano-waveguides under single-mode conditions, and the spatial distribution is more tunable in nano-waveguides with higher-order modes involved. Compared with the birefringent approach, transverse frequency conversion shows lower divergence angles, higher polarization, and more tunable spatial distribution.
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Well-dispersed lithium amidoborane nanoparticles through nanoreactor engineering for improved hydrogen release.
Nanoscale
PUBLISHED: 09-04-2014
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Well-distributed lithium amidoborane (LiAB) nanoparticles were successfully fabricated via adopting carbon nanofibers (CNFs) with homogenous pores uniformly containing Li3N as the nanoreactor and reactant, simply prepared by a single-nozzle electrospinning technique, for the subsequent interaction with AB. The hierarchical porous structure consists of various macropores, mesopores and micropores in situ produced during the formation of Li3N simultaneously serving as the reaction initiator, which not only controllably realizes the well-distribution of LiAB nanoparticles but also provides favorable channels for hydrogen release. Because of the hierarchical porous architecture and nanoscale size effects, the LiAB nanoparticles start to release hydrogen at only 40 °C, which is 30 °C lower than that of pure LiAB, and dehydrogenate completely within only 15 min at 100 °C (10.6 wt%). This work provides a new perspective to the controllable fabrication of nanosized hydrogen storage materials.
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Serum diamine oxidase as a hemorrhagic shock biomarker in a rabbit model.
PLoS ONE
PUBLISHED: 08-21-2014
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In prolonged hemorrhagic shock, reductions in intestinal mucosal blood perfusion lead to mucosal barrier damage and systemic inflammation. Gastrointestinal failure in critically ill patients has a poor prognosis, so early assessment of mucosal barrier injury in shock patients is clinically relevant. Unfortunately, there is no serum marker that can accurately assess intestinal ischemia-reperfusion injury.
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Large-scale transcriptome comparison reveals distinct gene activations in wheat responding to stripe rust and powdery mildew.
BMC Genomics
PUBLISHED: 07-18-2014
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Stripe rust (Puccinia striiformis f. sp. tritici; Pst) and powdery mildew (Blumeria graminis f. sp. tritici; Bgt) are important diseases of wheat (Triticum aestivum) worldwide. Similar mechanisms and gene transcripts are assumed to be involved in the host defense response because both pathogens are biotrophic fungi. The main objective of our study was to identify co-regulated mRNAs that show a change in expression pattern after inoculation with Pst or Bgt, and to identify mRNAs specific to the fungal stress response.
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CLIC1 overexpression is associated with poor prognosis in gallbladder cancer.
Tumour Biol.
PUBLISHED: 06-30-2014
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The chloride intracellular channel 1 (CLIC1) gene family is a recently identified class of Cl channel proteins. Although CLIC1 involvement is well established in some cancers such as gastric cancer and colon cancer, its expression pattern in gallbladder cancer (GBC) remains unknown. The aim of our study was to investigate the expression of CLIC1 in relation to progression and prognosis of GBC. Eight fresh gallbladder cancers paired with adjacent non-tumour tissues were quantified using real-time PCR and Western blot. Tissue samples from resected gallbladder cancer (n?=?75) and cholelithiasis (n?=?75) were evaluated for CLIC1 expression by immunohistochemical staining. Their expression was correlated with different clinicopathological parameters. CLIC1 expression was significantly higher (62.7 %) in gallbladder cancer than in cholelithiasis (21.3 %, p??0.05). Univariate Kaplan-Meier analysis showed that a positive CLIC1 expression was associated with a decreased overall survival (p?
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Hierarchical Porous Li2Mg(NH)2@C Nanowires with Long Cycle Life Towards Stable Hydrogen Storage.
Sci Rep
PUBLISHED: 06-27-2014
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The hierarchical porous Li2Mg(NH)2@C nanowires full of micropores, mesopores, and macropores are successfully fabricated via a single-nozzle electrospinning technique combined with in-situ reaction between the precursors, i.e., MgCl2 and LiN3, under physical restriction upon thermal annealing. The explosive decomposition of LiN3 well dispersed in the electrospun nanowires during carbothermal treatment induces a highly porous structure, which provides a favourable way for H2 delivering in and out of Li2Mg(NH)2 nanoparticles simultaneously realized by the space-confinement of the porous carbon coating. As a result, the thus-fabricated Li2Mg(NH)2@C nanowires present significantly enhanced thermodynamics and kinetics towards hydrogen storage performance, e.g., a complete cycle of H2 uptake and release with a capacity close to the theoretical value at a temperature as low as 105°C. This is, to the best of our knowledge, the lowest cycling temperature reported to date. More interestingly, induced by the nanosize effects and space-confinement function of porous carbon coating, a excellently stable regeneration without apparent degradation after 20 de-/re-hydrogenation cycles at a temperature as low as 130°C was achieved for the as-prepared Li2Mg(NH)2@C nanowires.
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p27 kip1 haplo-insufficiency improves cardiac function in early-stages of myocardial infarction by protecting myocardium and increasing angiogenesis by promoting IKK activation.
Sci Rep
PUBLISHED: 06-10-2014
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p27(kip1) (p27) is widely known as a potent cell cycle inhibitor in several organs, especially in the heart. However, its role has not been fully defined during the early phase of myocardial infarction (MI). In this study, we investigated the relationships between p27, vascular endothelial growth factor/hepatocyte growth factor (VEGF/HGF) and NF-?B in post-MI cardiac function repair both in vivo and in the hypoxia/ischemia-induced rat myocardiocyte model. In vivo, haplo-insufficiency of p27 improved cardiac function, diminished the infarct zone, protected myocardiocytes and increased angiogenesis by enhancing the production of VEGF/HGF. In vitro, the presence of conditioned medium from hypoxia/ischemia-induced p27 knockdown myocardiocytes reduced the injury caused by hypoxia/ischemia in myocardiocytes, and this effect was reversed by VEGF/HGF neutralizing antibodies, consistent with the cardioprotection being due to VEGF/HGF secretion. We also observed that p27 bound to IKK and that p27 haplo-insufficiency promoted IKK/p65 activation both in vivo and in vitro, thereby inducing the NF-?B downstream regulator, VEGF/HGF. Furthermore, IKKi and IKK inhibitor negated the effect of VEGF/HGF. Therefore, we conclude that p27 haplo-insufficiency protects against heart injury by VEGF/HGF mediated cardioprotection and increased angiogenesis through promoting IKK activation.
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Yes-associated protein 1 (YAP1) promotes human gallbladder tumor growth via activation of the AXL/MAPK pathway.
Cancer Lett.
PUBLISHED: 05-24-2014
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The transcriptional coactivator Yes-associated protein 1 (YAP1), a key regulator of cell proliferation and organ size in vertebrates, has been implicated in various malignancies. However, little is known about the expression and biological function of YAP1 in human gallbladder cancer (GBC). In this study we examined the clinical significance and biological functions of YAP1 in GBC and found that nuclear YAP1 and its target gene AXL were overexpressed in GBC tissues. We also observed a significant correlation between high YAP1 and AXL expression levels and worse prognosis. The depletion of YAP1 using lentivirus shRNAs significantly inhibited cell proliferation by inducing cell cycle arrest in S phase in concordance with the decrease of CDK2, CDC25A, and cyclin A, and resulted in increased cell apoptosis and invasive repression in GBC cell lines in vitro. Furthermore, knockdown of YAP1 also inhibited tumor growth in vivo. Additionally, we demonstrated that the activation of the AXL/MAPK pathway was involved in the oncogenic functions of YAP1 in GBC. These results demonstrated that YAP1 is a putative oncogene and represents a prognostic marker and potentially a novel therapeutic target for GBC.
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Angiographic features of transgenic mice with increased expression of human serine protease HTRA1 in retinal pigment epithelium.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 05-24-2014
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Polypoidal choroidal vasculopathy (PCV) is characterized by a branching vascular network (BVN) of choroid that terminates in polypoidal dilations. We have previously reported the generation of the first PCV model by transgenically expressing human HTRA1 (hHTRA1(+)), a multifunctional serine protease, in mouse RPE. The purpose of this study was to perform a comprehensive examination of the PCV phenotypes (e.g., lesion type and distribution) of hHTRA1(+) mice by a variety of in vivo imaging techniques.
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Bipolar radiofrequency ablation is useful for treating atrial fibrillation combined with heart valve diseases.
BMC Surg
PUBLISHED: 05-14-2014
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Atrial fibrillation (AF) is a common arrhymia, and it results in increased risk of thromboembolism and decreased cardiac function. In patients undergoing cardiac surgery, concomitant radiofrequency ablation to treat AF is effective in restoring sinus rhythm (SR). This study is an observational cohort study aimed to investigate the safety and efficacy of bipolar radiofrequency ablation (BRFA) for treating AF combined with heart valve diseases.
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[Anti-tumor effect of 5-FU-PLLA-CNTs on human gastric carcinoma cell lines in vitro].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 04-25-2014
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To prepare cisPLLAtin-loaded polylactic acid/cnts, and to study the anti-tumor effect of 5-FU-PLLA-CNTs on human gastric carcinoma cell lines(MGC803 and MNK45).
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[Individualized neurosurgical treatments of spastic cerebral palsy].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-22-2014
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To explore the outcomes of individualized neurosurgical treatments of spastic cerebral palsy.
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PERK pathway are involved in NO-induced apoptosis in endothelial cells cocultured with RPE under high glucose conditions.
Nitric Oxide
PUBLISHED: 04-14-2014
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Although excessive nitric oxide (NO) induced from iNOS is critical for dysfunction of vascular endothelial cells (ECs) in the diabetic retina, its role on ECs injury remains unknown. RPE (retinal pigment epithelium) is the pigmented cell layer just outside the neurosensory retina that constitutes the blood-retinal-barrier (BRB) with ECs, and also serves as the limiting transport factor that maintains the retinal environment. Dysfunction of the RPE is related to oxidative stress that contributes to the progression of diabetic retina. Using a co-cultural biosystem, we demonstrate that NO generation and iNOS expression was increased in both ECs and RPE cells after high glucose treatment. Increased NO in ECs cocultured with RPE activate the endoplasmic reticulum (ER) and protein kinase RNA (PKR)-like ER kinase (PERK) pathway and involved in ECs apoptosis. Blockade of the iNOS pathway, or depletion of PERK effectively, reverses NO-mediated apoptosis. Our study demonstrates that iNOS and subsequently excessive NO generation in RPE cells can have an unanticipated effect by activating PERK pathways in ECs, resulting in a novel mechanism for vascular endothelium to avoid injury from prolonged hyperglycemia.
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TGF-?1 stimulates human Tenon's capsule fibroblast proliferation by miR-200b and its targeting of p27/kip1 and RND3.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 03-27-2014
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To evaluate the role of miR-200b expression in the proliferation of human Tenon's capsule fibroblasts (HTFs) induced by transforming growth factor-beta 1 (TGF-?1).
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Pathophysilogical mechanism and treatment strategies for Leber congenital amaurosis.
Adv. Exp. Med. Biol.
PUBLISHED: 03-26-2014
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Mutations in retinoid isomerase, RPE65, or lecithin-retinol acyltransferase (LRAT) disrupt 11-cis-retinal recycling and cause Leber congenital amaurosis (LCA), the most severe retinal dystrophy in early childhood. We used Lrat (-/-), a murine model for LCA, to investigate the mechanism of rapid cone degeneration. We found that mislocalized M-opsin was degraded whereas mislocalized S-opsin accumulated in Lrat (-/-) cones before the onset of massive ventral/central cone degeneration. Since the ventral and central retina expresses higher levels of S-opsin than the dorsal retina in mice, our results may explain why ventral and central cones degenerate more rapidly than dorsal cones in Rpe65 (-/-) and Lrat (-/-) LCA models. In addition, human blue opsin and mouse S-opsin, but not mouse M-opsin or human red/green opsins, aggregated to form cytoplasmic inclusions in transfected cells, which may explain why blue cone function is lost earlier than red/green-cone function in LCA patients. The aggregation of short-wavelength opsins likely caused rapid cone degenerations through an ER stress pathway as demonstrated in both the Lrat (-/-) retina and transfected cells. Based on this mechanism, we designed a new therapy of LCA by reducing ER stress. We found that systemic injection of an ER chemical chaperone, tauroursodeoxycholic acid (TUDCA), is effective in reducing ER stress, preventing apoptosis, and preserving cones in Lrat (-/-) mice.
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Whole-exome and targeted gene sequencing of gallbladder carcinoma identifies recurrent mutations in the ErbB pathway.
Nat. Genet.
PUBLISHED: 03-23-2014
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Individuals with gallbladder carcinoma (GBC), the most aggressive malignancy of the biliary tract, have a poor prognosis. Here we report the identification of somatic mutations for GBC in 57 tumor-normal pairs through a combination of exome sequencing and ultra-deep sequencing of cancer-related genes. The mutation pattern is defined by a dominant prevalence of C>T mutations at TCN sites. Genes with a significant frequency (false discovery rate (FDR)<0.05) of non-silent mutations include TP53 (47.1%), KRAS (7.8%) and ERBB3 (11.8%). Moreover, ErbB signaling (including EGFR, ERBB2, ERBB3, ERBB4 and their downstream genes) is the most extensively mutated pathway, affecting 36.8% (21/57) of the GBC samples. Multivariate analyses further show that cases with ErbB pathway mutations have a worse outcome (P=0.001). These findings provide insight into the somatic mutational landscape in GBC and highlight the key role of the ErbB signaling pathway in GBC pathogenesis.
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MiR-199a-5p loss up-regulated DDR1 aggravated colorectal cancer by activating epithelial-to-mesenchymal transition related signaling.
Dig. Dis. Sci.
PUBLISHED: 03-23-2014
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Discoidin domain receptors1 (DDR1) is associated with tumor progression, and its dysregulated expression has been observed in many cancers.
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Detecting abnormalities in choroidal vasculature in a mouse model of age-related macular degeneration by time-course indocyanine green angiography.
J Vis Exp
PUBLISHED: 03-19-2014
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Indocyanine Green Angiography (or ICGA) is a technique performed by ophthalmologists to diagnose abnormalities of the choroidal and retinal vasculature of various eye diseases such as age-related macular degeneration (AMD). ICGA is especially useful to image the posterior choroidal vasculature of the eye due to its capability of penetrating through the pigmented layer with its infrared spectrum. ICGA time course can be divided into early, middle, and late phases. The three phases provide valuable information on the pathology of eye problems. Although time-course ICGA by intravenous (IV) injection is widely used in the clinic for the diagnosis and management of choroid problems, ICGA by intraperitoneal injection (IP) is commonly used in animal research. Here we demonstrated the technique to obtain high-resolution ICGA time-course images in mice by tail-vein injection and confocal scanning laser ophthalmoscopy. We used this technique to image the choroidal lesions in a mouse model of age-related macular degeneration. Although it is much easier to introduce ICG to the mouse vasculature by IP, our data indicate that it is difficult to obtain reproducible ICGA time course images by IP-ICGA. In contrast, ICGA via tail vein injection provides high quality ICGA time-course images comparable to human studies. In addition, we showed that ICGA performed on albino mice gives clearer pictures of choroidal vessels than that performed on pigmented mice. We suggest that time-course IV-ICGA should become a standard practice in AMD research based on animal models.
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MicroRNA-216b/Beclin 1 axis regulates autophagy and apoptosis in human Tenon's capsule fibroblasts upon hydroxycamptothecin exposure.
Exp. Eye Res.
PUBLISHED: 03-17-2014
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Proliferation and fibrosis of human Tenon's fibroblasts (HTFs) have significantly challenged the outcome of glaucoma filtration surgery. Hydroxycamptothecin (HCPT) is considered as a potential chemical to overcome this issue as it was previously shown that HCPT inhibited cell proliferation and induced apoptosis in fibroblasts. Here, we further dissected the molecular pathway, through which the HCPT inhibit the proliferation of HTFs. We showed that HCPT induced significant autophagy as well as apoptosis, two self-destructive processes, and down-regulated the expression of miR-216b in HTFs. Overexpression of miR-216b in HTFs suppressed the autophagy and apoptosis induced by HCPT, whereas silence of miR-216b led to effects that were similar to those caused by the treatment with HCPT. Further, we showed that miR-216b could directly target a specific fragment in the 3' untranslated region of Beclin 1 as demonstrated by luciferase assay, and consequently decreased the expression of Beclin 1. Consistently, knocking down Beclin 1 significantly decreased HCPT-triggered autophagy and apoptosis, and increased the viability of HTFs treated with HCPT, thus implicating that Beclin 1 functions as a pro-apoptotic molecule in this circumstance. Altogether, we concluded that miR-216b regulated both autophagy and apoptosis by modulating Beclin 1 in HTFs treated with HCPT. We also demonstrated that HCPT-induced autophagy is one of the agent's anti-proliferative effects.
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The diameters and number of nerve fibers in spinal nerve roots.
J Spinal Cord Med
PUBLISHED: 03-11-2014
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Objective To investigate the anatomical and histological features of spinal nerve roots and provide base data for neuroanastomosis therapy for paraplegia. Methods Spinal nerve roots from C1 to S5 were exposed on six adult cadavers. The diameter and the number of nerve fibers of each nerve root were measured, respectively, with a caliper and image analysis software. Results As for ventral roots, the diameter of C5 (2.50 ± 0.55 mm) was the largest in cervical segments. In thoracic and lumbosacral segments, the diameter gradually increased from T11 to S1 and then decreased from S1 to S5 except L3. S1 (1.43 ± 0.16 mm) was the thickest root and S5 (0.14 ± 0.02 mm) was the thinnest one. As for dorsal roots, the diameter of C7 (4.61 ± 0.87 mm) was the largest in cervical segments. From T11 to S1, the diameter increased and then decreased gradually from S1 to S5. The diameter of dorsal roots from T1 to S5 was largest at S1 (2.95 ± 0.57 mm) and smallest at S5 (0.27 ± 0.13 mm), respectively. C7 (8467 ± 1019), T12 (6538 ± 892), L3 (9169 ± 1160), and S1 (8253 ± 1419) ventral roots contained the most nerve fibers in cervical, thoracic, lumbar, and sacral segments, respectively. Similarly, C7 (39 653 ± 8458), T1 (26 507 ± 7617), L5 (34 455 ± 2740), and S1 (41 543 ± 3036) dorsal roots, respectively, contained the most nerve fibers in their corresponding segments. Conclusion The findings in the current study provided the imperative data and may be valuable for spinal nerve root microanastomosis surgery in the paraplegic patients.
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Oridonin induces apoptosis and cell cycle arrest of gallbladder cancer cells via the mitochondrial pathway.
BMC Cancer
PUBLISHED: 03-06-2014
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Gallbladder cancer is the most frequent malignancy of the bile duct with high aggressive and extremely poor prognosis. The main objective of the paper was to investigate the inhibitory effects of oridonin, a diterpenoid isolated from Rabdosia rubescens, on gallbladder cancer both in vitro and in vivo and to explore the mechanisms underlying oridonin-induced apoptosis and cell cycle arrest.
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Candidemia: incidence rates, type of species, and risk factors at a tertiary care academic hospital in China.
Int. J. Infect. Dis.
PUBLISHED: 02-28-2014
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To investigate the incidence rates of candidemia in hospitalized patients and to identify differences in risk factors of patients with Candida albicans and non-C. albicans and with Candida guilliermondii and non-C. guilliermondii candidemia.
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Enzymatic synthesis of 2'-deoxyuridine by whole cell catalyst co-expressing uridine phosphorylase and thymidine phosphorylase through auto-induction system.
J. Biosci. Bioeng.
PUBLISHED: 02-24-2014
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Genes encoding uridine phosphorylase (UP) and thymidine phosphorylase (TP) from Escherichia coli K12 were cloned and recombined respectively into plasmids pET-21a(+) and pET-28a(+). The recombinant plasmids BL21/pET21a-UP and BL21/pET28a-TP were co-transformed into E. coli BL21(DE3) to construct highly effective BTU strain (BL21/pET28a-TP, pET21a-UP) overexpressing both of UP and TP. BTU was cultivated in ZYM-Fe-5052 medium for 10 h and used as catalyst to synthesize 2'-deoxyuridine (dUR). It was found to increase the productivity of dUR by 8-9 fold when compared to wild E. coli K12 and E. coli BL21(DE3) strains. A series of experiments were carried out to find out the optimal conditions for synthesis of dUR. At 50°C, with 0.25‰ dry wt./v to catalyze the reaction of 2:1 ?-thymidine: uracil (60 mM ?-thymidine, 30 mM uracil), the conversion rate of dUR would reach 61.6% at 1 h, which was much higher than the rates obtained by BTU strain cultured in LB medium and induced by IPTG. This result proved co-expression and auto-induction were efficient methods in enhancing the expression quantity and activity of nucleoside phosphorylases, and they also had significant implications for large-scale industrial production of dUR and synthesis of other nucleoside derivatives.
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Downregulation of VEGF expression attenuates malignant biological behavior of C6 glioma stem cells.
Int. J. Oncol.
PUBLISHED: 02-14-2014
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Several lines of direct evidence show that gliomas express high levels of vascular endothelial growth factor (VEGF). VEGF can promote the growth of gliomas through angiogenesis. It is believed that gliomas originate in the brain tumor stem cells (BTSCs). However, the direct effect of VEGF on the biological behavior of BTSCs has not been completely elucidated. In this study, we established C6 glioma stem cells (C6GSCs) from the C6 glioma cells. Furthermore, we suppressed the VEGF expression of C6GSCs using lentiviral vector-VEGF shRNA. After transfection, the VEGF expression of C6GSCs was downregulated significantly. The proliferation and invasion capacity of transfected C6GSCs was impaired and the ability of differentiation was enhanced. The data demonstrate that downregulation of VEGF expression attenuates malignant biological behavior of C6GSCs. RNA interference of VEGF expression implies an effective anti-gliomas strategy.
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Ventilator-associated pneumonia after cardiac surgery: A meta-analysis and systematic review.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 02-13-2014
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Ventilator-associated pneumonia (VAP) is the most common and serious nosocomial infection that threatens patients who have undergone cardiac surgery. This article summarizes its clinical characteristics and provides theoretical evidence for prevention and treatment.
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Genetic variations of MMP9 gene and intracerebral hemorrhage susceptibility: a case-control study in Chinese Han population.
J. Neurol. Sci.
PUBLISHED: 02-08-2014
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To investigate the association between genetic variations of matrix metalloproteinase 9 (MMP9) gene and intracerebral hemorrhage (ICH) susceptibility in Chinese Han population.
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Role of polymorphisms of the IGF2 and IGFBP3 genes and risk of gastric carcinoma in China.
Chin. Med. J.
PUBLISHED: 01-24-2014
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The insulin-like growth factor signaling pathway plays an important role in the modulation of cell growth and proliferation. The aim of this study was to investigate the role of polymorphisms of the insulin-like growth factor 2 (IGF2) and IGF-binding protein 3 (IGFBP3) genes, which encode key proteins of this pathway, as risk factors for gastric carcinoma (GC).
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Erythropoietin enhances mitochondrial biogenesis in cardiomyocytes exposed to chronic hypoxia through Akt/eNOS signalling pathway.
Cell Biol. Int.
PUBLISHED: 01-16-2014
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Adaptation of cardiomyocytes to chronic hypoxia in cyanotic patients remains unclear. Mitochondrial biogenesis is enhanced in myocardium from cyanotic patients, which is possibly an adaptive response. Erythropoietin (EPO) in blood and its receptor (EPOR) on cardiomyocytes are upregulated by chronic hypoxia, suggesting that EPO-EPOR interaction is increased, which is inferred to positively regulate mitochondrial biogenesis through protein kinase B (Akt)/endothelial nitric oxide synthase (eNOS) signalling pathway. H9c2 cardiomyocytes were exposed to hypoxia (1% O(2)) for 1 week and treated with different doses of recombinant human erythropoietin (rhEPO). Mitochondrial number, mitochondrial DNA (mtDNA) copy number and peroxisome proliferator activated receptor gamma coactivator alpha (PGC-1?) mRNA expression increased in a dose-dependent manner induced by rhEPO. Akt and eNOS were significantly phosphorylated by rhEPO. Both blocking Akt with Wortmannin and silencing eNOS expression with shRNA plasmid decreased the mtDNA copy number and PGC-1? mRNA expression induced by rhEPO. Blocking Akt was associated with the decreased phosphorylation of Akt and eNOS. RNA interference led to a reduction in the total and phosphorylated proteins of eNOS. Thus EPO enhances mitochondrial biogenesis in cardiomyocytes exposed to chronic hypoxia, at least partly through Akt/eNOS signalling, which might be an adaptive mechanism of cardiomyocytes associated with the increased EPO-EPOR interaction in patients with cyanotic congenital heart disease (CCHD).
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Thioridazine, an antipsychotic drug, elicits potent antitumor effects in gastric cancer.
Oncol. Rep.
PUBLISHED: 01-10-2014
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Thioridazine, an antipsychotic drug, has been reported to induce apoptosis in various types of cancer cells, with specificity on targeting cancer stem cells (CSCs). However, whether it elicits anticancer effects in gastric cancer has never been reported. In the present study, we examined the ability of thioridazine to induce cell death in the gastric cancer cell lines NCI-N87 and AGS, and detected its in vivo tumor inhibition capacity. Thioridazine elicited cytotoxic effects on NCI-N87 and AGS cells in a dose-dependent manner, and inhibited the colony formation abilitiy of the NCI-N87 and AGS cells. Thioridazine treatment induced nuclear fragmentation, increased the proportion of sub-G1 phase cells, and elevated the percentage of Annexin V-positive cells, suggesting the occurrence of apoptosis. Moreover, thioridazine induced gastric cancer cell apoptosis in a caspase-dependent manner, as shown by a decrease in the precursors of casapse-9, caspase-8 and caspase-3, and by the ability of the caspase inhibitor Z-VAD-FMK to reverse the cytotoxic effect of thioridazine. JC-1 staining further revealed that thioridazine induced gastric cancer cell apoptosis via the mitochondrial pathway. In addition, thioridazine pretreatment inhibited the growth of NCI-N87 cell-derived tumors. The present study demonstrated that the antipsychotic drug thioridazine possesses anti-gastric cancer ability through in vitro and in vivo experiments, suggesting thioridazine as a potential drug in gastric cancer therapy.
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Validation of EORTC IN-PATSAT32 for Chinese patients with gastrointestinal cancer.
Patient Prefer Adherence
PUBLISHED: 01-01-2014
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To test the psychometric properties and applicability of the European Organization for Research and Treatment of Cancer In-patient Satisfaction with Care Questionnaire 32 (EORTC IN-PATSAT32) for Chinese patients with gastrointestinal cancer.
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Conditioned medium from hypoxic bone marrow-derived mesenchymal stem cells enhances wound healing in mice.
PLoS ONE
PUBLISHED: 01-01-2014
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Growing evidence indicates that bone marrow-derived mesenchymal stem cells (BM-MSCs) enhance wound repair via paracrine. Because the extent of environmental oxygenation affects the innate characteristics of BM-MSCs, including their stemness and migration capacity, the current study set out to elucidate and compare the impact of normoxic and hypoxic cell-culture conditions on the expression and secretion of BM-MSC-derived paracrine molecules (e.g., cytokines, growth factors and chemokines) that hypothetically contribute to cutaneous wound healing in vivo. Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) analyses of normoxic and hypoxic BM-MSCs and their conditioned medium fractions showed that the stem cells expressed and secreted significantly higher amounts of basic fibroblast growth factor (bFGF),vascular endothelial growth factor A (VEGF-A) interleukin 6 (IL-6) and interleukin 8 (IL-8) under hypoxic conditions. Moreover, hypoxic BM-MSC-derived conditioned medium (hypoCM) vs. normoxic BM-MSC-derived conditioned medium (norCM) or vehicle control medium significantly enhanced the proliferation of keratinocytes, fibroblasts and endothelial cells, the migration of keratinocytes, fibroblasts, endothelial cells and monocytes, and the formation of tubular structures by endothelial cells cultured on Matrigel matrix. Consistent with these in vitro results, skin wound contraction was significantly accelerated in Balb/c nude mice treated with topical hypoCM relative to norCM or the vehicle control. Notably increased in vivo cell proliferation, neovascularization as well as recruitment of inflammatory macrophages and evidently decreased collagen I, and collagen III were also found in the hypoCM-treated group. These findings suggest that BM-MSCs promote murine skin wound healing via hypoxia-enhanced paracrine.
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Granulocyte/macrophage colony-stimulating factor influences angiogenesis by regulating the coordinated expression of VEGF and the Ang/Tie system.
PLoS ONE
PUBLISHED: 01-01-2014
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Granulocyte/macrophage colony-stimulating factor (GM-CSF) can accelerate wound healing by promoting angiogenesis. The biological effects of GM-CSF in angiogenesis and the corresponding underlying molecular mechanisms, including in the early stages of primitive endothelial tubule formation and the later stages of new vessel maturation, have only been partially clarified. This study aimed to investigate the effects of GM-CSF on angiogenesis and its regulatory mechanisms. Employing a self-controlled model (Sprague-Dawley rats with deep partial-thickness burn wounds), we determined that GM-CSF can increase VEGF expression and decrease the expression ratio of Ang-1/Ang-2 and the phosphorylation of Tie-2 in the early stages of the wound healing process, which promotes the degradation of the basement membrane and the proliferation of endothelial cells. At later stages of wound healing, GM-CSF can increase the expression ratio of Ang-1/Ang-2 and the phosphorylation of Tie-2 and maintain a high VEGF expression level. Consequently, pericyte coverages were higher, and the basement membrane became more integrated in new blood vessels, which enhanced the barrier function of blood vessels. In summary, we report here that increased angiogenesis is associated with GM-CSF treatment, and we indicate that VEGF and the Ang/Tie system may act as angiogenic mediators of the healing effect of GM-CSF on burn wounds.
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Investigation on the antibacterial micro-porous titanium with silver nano-particles.
J Nanosci Nanotechnol
PUBLISHED: 11-20-2013
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Micro-porous titanium is coated with silver nanoparticles by using a simple chemical reduction method that exhibits excellent antibacterial ability. Scanning electron microscopy (SEM) shows that the silver nanoparticles with average sizes of about 100 nm are formed homogeneously on the micro-porous titanium surface. After the micro-porous Ti coated with silver nano particles is treated by heating, the average size of the silver nano particles is slightly increased, but the nano particles are more uniformly dispersed on the surface of the micro-porous titanium. X-ray diffraction (XRD) indicates that those nanoparticles are metallic silver produced on the micro-porous titanium surface. The samples of micro-porous titanium coated with silver nanoparticles inhibit the growth of Escherichia coli. Our results show that the electrical double layer of the samples play an important role in the antibiosis and this study opens a new window for antibacterial mechanism which may be suitable for the other antibacterial metallic materials.
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miR-138 protects cardiomyocytes from hypoxia-induced apoptosis via MLK3/JNK/c-jun pathway.
Biochem. Biophys. Res. Commun.
PUBLISHED: 10-22-2013
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Cardiomyocytes experience a series of complex endogenous regulatory mechanisms against apoptosis induced by chronic hypoxia. MicroRNAs are a class of endogenous small non-coding RNAs that regulate cellular pathophysiological processes. Recently, microRNA-138 (miR-138) has been found related to hypoxia, and beneficial for cell proliferation. Therefore, we intend to study the role of miR-138 in hypoxic cardiomyocytes and the main mechanism. Myocardial samples of patients with congenital heart disease (CHD) were collected to test miR-138 expression. Agomir or antagomir of miR-138 was transfected into H9C2 cells to investigate its effect on cell apoptosis. Higher miR-138 expression was observed in patients with cyanotic CHD, and its expression gradually increased with prolonged hypoxia time in H9C2 cells. Using MTT and LDH assays, cell growth was significantly greater in the agomir group than in the negative control (NC) group, while antagomir decreased cell survival. Dual luciferase reporter gene and Western-blot results confirmed MLK3 was a direct target of miR-138. It was found that miR-138 attenuated hypoxia-induced apoptosis using TUNEL, Hoechst staining and Annexin V-PE/7-AAD flow cytometry analysis. We further detected expression of apoptosis-related proteins. In the agomir group, the level of pro-apoptotic proteins such as cleaved-caspase-3, cleaved-PARP and Bad significantly reduced, while Bcl-2 and Bcl-2/Bax ratio increased. Opposite changes were observed in the antagomir group. Downstream targets of MLK3, JNK and c-jun, were also suppressed by miR-138. Our study demonstrates that up-regulation of miR-138 plays a protective role in myocardial adaptation to chronic hypoxia, which is mediated mainly by MLK3/JNK/c-jun signaling pathway.
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Risk compensation behaviours in construction workers activities.
Int J Inj Contr Saf Promot
PUBLISHED: 10-19-2013
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The purpose of this study was to test whether the construction workers have the tendency of engaging in risk compensation behaviours, and identify the demographic variables, which may influence the extent to which the construction workers may show risk compensation behaviours. Both quantitative (survey) and qualitative (interviews) approaches were used in this study. A questionnaire survey was conducted with all the construction workers on three building construction sites of a leading construction company in Australia. Semi-structured interviews were then conducted to validate the findings of the quantitative research. The findings indicate that workers tend to show risk compensation behaviours in the construction environment. The workers with more working experience, higher education, or having never been injured at work before have a higher tendency to show risk compensation in their activities than the others. The implication is that contractors need to assess the potential influence of workers risk compensation behaviours when evaluating the effect of risk control measures. It is recommended that supervisors pay more attention to the behavioural changes of those workers who have more experience, higher education, and have never been injured before after the implementation of new safety control measures on construction site.
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Mesenchymal stem cells overexpressing C-X-C chemokine receptor type 4 improve early liver regeneration of small-for-size liver grafts.
Liver Transpl.
PUBLISHED: 08-06-2013
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Mesenchymal stem cell (MSC) therapy can prevent hepatic parenchymal cell loss and promote tissue repair. However, poor MSC engraftment is one of the primary barriers to the effectiveness of cell therapy because culture-expanded MSCs progressively down-regulate C-X-C chemokine receptor type 4 (CXCR4) expression and lose their ability to migrate toward a concentration gradient of stromal cell-derived factor 1a (SDF1a). In this study, we investigated whether a CXCR4-MSC infusion could protect hepatocytes and stimulate regeneration in 50% reduced size liver transplantation (RSLT). Rats that underwent 50% RSLT were randomly divided into 3 groups: a phosphate-buffered solution group (PBS), a green fluorescent protein (GFP)-MSC group, and a CXCR4-MSC group. Rats received 1 mL of PBS with or without a resuspension of GFP-MSCs or CXCR4-MSCs. The factors secreted by MSCs, the graft function, the apoptosis and proliferation of hepatocytes, the efficacy of MSC engraftment, and the expression of SDF1?, albumin (Alb), and cytokeratin 18 (CK18) in engrafted GFP-positive MSCs were assessed. A systemic infusion of GFP-MSCs led to a reduction of the release of liver injury biomarkers and apoptosis of hepatocytes; CXCR4 overexpression did not further reduce the liver injury. However, CXCR4 overexpression enhanced MSC engraftment in liver grafts, improved the effect on the proliferation of hepatocytes, and thus provided a significant 1-week survival benefit. SDF1? expression in grafts was elevated after transplanted CXCR4-MSCs were recruited to the remnant liver. However, engrafted MSCs did not express the markers of hepatocytes, including Alb and CK18, in vivo 168 hours after transplantation. CXCR4 overexpression enhanced the mobilization and engraftment of MSCs into small-for-size liver grafts, in which these cells promoted the early regeneration of the remnant liver not by direct differentiation but perhaps by a paracrine mechanism.
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COL1A1 polymorphism is associated with risks of osteosarcoma susceptibility and death.
Tumour Biol.
PUBLISHED: 07-30-2013
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Osteosarcoma is a life-threatening malignancy that often occurs in teenagers. Collagen type I alpha 1 (COL1A1) polymorphism is reportedly associated with the occurrence of several human diseases. However, the relationship between COL1A1 and osteosarcoma occurrence remains unknown, and there is no report about the prevalence of COL1A1 in osteosarcoma. The purpose of this study is to investigate the associations of COL1A1 polymorphism with the susceptibility and survival of osteosarcoma. The relative risk to develop osteosarcomas and the overall survival associated to COL1A1 polymorphism were investigated in a homogeneous group of 189 osteosarcomas patients. Correlations with overall survival and hazard ratios (HR) were also analyzed. CT genotype and C allele of COL1A1 at rs1061970, and CG genotype and G allele of COL1A1 at rs2075559 are associated with decreased susceptibility to osteosarcoma in the Chinese population. CC genotype and C allele of COL1A1 at rs1061970 are associated with nonmetastasis in patients. CC genotype and CT genotype of COL1A1 at rs1061970 are associated with lower risk of death. Metastasis was found to be an independent prognostic factor for survival. This study provides the first evidence for the association between COL1A1 polymorphism and osteosarcoma risk in Chinese and shows that COL1A1 polymorphism at rs1061970 has a prognostic value for overall survival in osteosarcoma patients.
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Upregulation of DNMT1 mediated by HBx suppresses RASSF1A expression independent of DNA methylation.
Oncol. Rep.
PUBLISHED: 07-29-2013
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The hepatitis B virus (HBV) X protein (HBx) plays a key role in the molecular pathogenesis of HBV-related hepatocellular carcinoma (HCC). However, its critical gene targets remain largely unknown. RASSF1A gene (Ras-association domain family 1A, RASSF1A), a tumor-suppressor gene, is frequently found to be hypermethylated and downregulated in HCC. In the present study, we investigated whether HBx is involved in the hypermethylation and downregulation of RASSF1A and we examined the potential regulation mechanisms. RT-PCR analysis was used to determine RASSF1A and HBx expression in 9 liver cell lines and the results showed that RASSF1A expression was relatively low in HBx-positive cells. Notably, RASSF1A was downregulated in HepG2.2.15 cells, as compared to HepG2 cells. Further analysis revealed that HBx transfection suppressed RASSF1A expression and HBx knockdown induced its expression. Enforced HBx suppressed RASSF1A and meanwhile induced DNMT1 and DNMT3B expression. In addition, RASSF1A is negatively regulated by DNMT1. ChIP analysis using an antibody against DNMT1 revealed that HBx enhanced the binding of DNMT1 to the RASSF1A promoter but the inhibition of RASSF1A by HBx is DNA methylation-independent as detected by methylation-specific PCR (MSP). Further studies using MSP and bisulfite genomic sequencing (BGS) revealed that no significant methylation changes were observed for regional methylation levels of RASSF1A in DNMT1 knockdown cells, although methylation levels of specific CpG sites at the predicted binding sites for the Sp1 and USF transcription factors were reduced. Additionally, RASSF1A was downregulated in HBV-associated HCC (HBV-HCC) as detected by RT-PCR and immunohistochemistry suggesting RASSF1A expression may be related to HBx in HCC and the clinical relevance of our observations. Collectively, our data showed that HBx suppressed RASSF1A expression via DNMT1 and offered a new mechanism of RASSF1A inactive in HCC in addition to the widely known DNA methylation, enriching the epigenetic mechanism by which HBx contributes to the pathogenesis of HBV-HCC.
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Complete preservation of the mitral valve apparatus during mitral valve replacement for rheumatic mitral regurgitation in patients with an enlarged left ventricular chamber.
Heart Surg Forum
PUBLISHED: 06-28-2013
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The merits of retaining the subvalvular apparatus during mitral valve replacement (MVR) for chronic mitral regurgitation have been demonstrated in clinical investigations. This study was to investigate the feasibility of total preservation of the leaflet and subvalvular apparatus at the native anatomic position during MVR in a rheumatic population with enlarged left ventricular chamber.
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Regulation of cell proliferation and migration in gallbladder cancer by zinc finger X-chromosomal protein.
Gene
PUBLISHED: 06-23-2013
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Gallbladder carcinoma (GBC) is one of the mostly aggressive and fatal malignancies. However, little is known about the oncogenic genes that contributed to the development of GBC. Zinc finger X-chromosomal protein (ZFX) was a novel member of the Krueppel C2H2-type zinc-finger protein family and its down-regulation led to impaired cell growth in human laryngeal squamous cell carcinoma. Here, we aim to investigate the function of ZFX in GBC cell proliferation and migration. Loss of function analysis was performed on GBC cell line (GBC-SD) using lentivirus-mediated siRNA against ZFX. The proliferation, in vitro tumorigenesis (colony-formation) ability as well as cell migration was significantly suppressed after GBC-SD cells which were infected with ZFX-siRNA-expressing lentivirus (Lv-shZFX). Our finding suggested that ZFX promoted the growth and migration of GBC cells and could present a potential molecular target for gene therapy of GBC.
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Hydroxycamptothecin induces apoptosis of human tenons capsule fibroblasts by activating the PERK signaling pathway.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 06-14-2013
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Hydroxycamptothecin (HCPT) has been proven to induce apoptosis in fibroblasts. In this study, we investigated whether the PRKR-like ER kinase (PERK) pathway is implicated in apoptotic signaling of human Tenons capsule fibroblasts (HTCFs) by HCPT.
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[Application of occlusal guide plate combined with intermaxillary fixation screw in mandibular defect repair with free fibular flap].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 05-16-2013
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To investigate the clinical value of occlusal guide plate combined with intermaxillary fixation screw in mandibular defect repair with free fibular flap.
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Prognostic significance of nemo-like kinase (NLK) expression in patients with gallbladder cancer.
Tumour Biol.
PUBLISHED: 05-04-2013
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Nemo-like kinase (NLK), a serine/threonine protein kinase, has been implicated in tumor development and progression, and plays an important role in diverse signaling pathways by phosphorylating a variety of transcription factors. Recent studies demonstrated that altered expression of NLK was observed in various types of human cancers. However, the clinical significance of NLK expression in gallbladder cancer (GBC) remains largely unknown. In this study, we focused on the clinical significance of NLK in GBC, and found that nuclear NLK protein overexpression was frequently detected in GBC tissues. The overexpression of NLK was significantly correlated with histological grade, TNM stage, and perineural invasion. The results of Kaplan-Meier analysis indicated that a high expression level of NLK resulted in a significantly poorer prognosis of GBC patients (P?=?0.002). Furthermore, multivariate Cox regression analysis showed that high NLK expression was an independent prognostic factor for GBC patients (HR?=?3.077). In conclusion, overexpression of NLK is closely related to progression of GBC, and NLK could be used as a potential prognostic marker for GBC patients.
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SECTM1 Produced by Tumor Cells Attracts Human Monocytes via CD7-Mediated Activation of the PI3K Pathway.
J. Invest. Dermatol.
PUBLISHED: 04-30-2013
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Tumor-associated macrophages (TAMs) have essential roles in tumor progression and metastasis. Tumor cells recruit myeloid progenitors and monocytes to the tumor site, where they differentiate into TAMs; however, this process is not well studied in humans. Here we show that human CD7, a T-cell and NK cell receptor, is highly expressed by monocytes and macrophages. Expression of CD7 decreases in M-CSF-differentiated macrophages and in melanoma-conditioned medium-induced macrophages (MCMI/M?) in comparison to monocytes. A ligand for CD7, SECTM1 (secreted and transmembrane protein 1), is highly expressed in many tumors, including melanoma cells. We show that SECTM1 binds to CD7 and significantly increases monocyte migration by activation of the PI3K (phosphatidylinositol 3-kinase) pathway. In human melanoma tissues, tumor-infiltrating macrophages expressing CD7 are present. These melanomas, with CD7-positive inflammatory cell infiltrations, frequently highly express SECTM1, including an N-terminal, soluble form, which can be detected in the sera of metastatic melanoma patients but not in normal sera. Taken together, our data demonstrate that CD7 is present on monocytes and tumor macrophages and that its ligand, SECTM1, is frequently expressed in corresponding melanoma tissues, possibly acting as a chemoattractant for monocytes to modulate the melanoma microenvironment.Journal of Investigative Dermatology advance online publication, 21 November 2013; doi:10.1038/jid.2013.437.
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Carbon-coated Li3 N nanofibers for advanced hydrogen storage.
Adv. Mater. Weinheim
PUBLISHED: 04-30-2013
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3D porous carbon-coated Li3 N nanofibers are successfully fabricated via the electrospinning technique. The as-prepared nanofibers exhibit a highly improved hydrogen-sorption performance in terms of both thermodynamics and kinetics. More interestingly, a stable regeneration can be achieved due to the unique structure of the nanofibers, over 10 cycles of H2 sorption at a temperature as low as 250 °C.
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A Phe-rich region in short-wavelength sensitive opsins is responsible for their aggregation in the absence of 11-cis-retinal.
FEBS Lett.
PUBLISHED: 04-18-2013
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Human blue and mouse S-opsin are prone to aggregation in the absence of 11-cis-retinal, which underlie the rapid cone degeneration in human patients and animal models of Leber congenital amaurosis (LCA). By in silico analysis and domain swapping experiments, we show that a Phe-rich region in short-wavelength sensitive (SWS) opsins, but not in medium/long-wavelength sensitive opsins, is responsible for SWS opsin aggregation. Mutagenesis studies suggest that Phe residues in this region are critical in mediating protein aggregation. Fusing the Phe-rich region of SWS opsins to GFP causes the latter to aggregate. Our findings suggest that new therapeutics can be designed to disrupt the Phe-rich region in preventing cone degeneration due to S-opsin aggregation in LCA.
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Molecular assays for quantitative and qualitative detection of influenza virus and oseltamivir resistance mutations.
J Mol Diagn
PUBLISHED: 04-16-2013
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Sensitive and reproducible molecular assays are essential for influenza virus diagnostics. This manuscript describes the design, validation, and evaluation of a set of real-time RT-PCR assays for quantification and subtyping of human influenza viruses from patient respiratory material. Four assays are included for detection of oseltamivir resistance mutations H275Y in prepandemic and pandemic influenza A/H1N1 and E119V and R292K in influenza A/H3N2 neuraminidase. The lower limits of detection of the quantification assay were determined to be 1.7 log(10) virus particles per milliliter (vp/mL) for influenza A and 2.2 log(10) vp/mL for influenza B virus. The lower limits of quantification were 2.1 and 2.3 log(10) vp/mL, respectively. The RT-PCR efficiencies and lower limits of detection of the quantification assays were only marginally affected when tested on the most dissimilar target sequences found in the GenBank database. Finally, the resistance RT-PCR assays detected at least 5% mutant viruses present in mixtures containing both wild-type and mutant viruses with approximated limits of detection of 2.4 log(10) vp/mL. Overall, this set of RT-PCR assays is a powerful tool for enhanced influenza virus surveillance.
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Downregulated expression of hepatoma-derived growth factor (HDGF) reduces gallbladder cancer cell proliferation and invasion.
Med. Oncol.
PUBLISHED: 03-27-2013
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Hepatoma-derived growth factor (HDGF), a heparin-binding growth factor, has a wide range of biological functions, including mitogenic activity and vascular development. Recent studies demonstrated that HDGF also acted as an oncogene with aberrantly increased activity in multiple human cancers; however, little is known about the biological function of HDGF in gallbladder cancer (GBC). In this study, we focused on the clinical significance and biological functions of HDGF in GBC and found that Nuclear HDGF protein overexpression was frequently detected in GBC tissues. Patients with nuclear HDGF-positive tumors had worse overall survival than patients with HDGF-negative tumors. Furthermore, treatment of GBC lines with HDGF-targeting siRNA oligonucleotides (HDGF-siRNA) significantly reduced the proliferation of GBC-SD and SGC-996 cell lines and diminished both anchorage-independent growth on soft agar and cell migration. These data indicate that HDGF acts as a putative oncogene in GBC and could be a novel diagnostic and therapeutic target for GBC.
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[Advanced oxidation protein products inhibit proliferation and differentiation of rat osteoblasts through oxidative stress].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 03-27-2013
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To investigate the effect of advanced oxidation protein products (AOPP) on proliferation, differentiation, and oxidative stress in rat osteoblasts.
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Effect of advanced oxidation protein products on the proliferation and osteogenic differentiation of rat mesenchymal stem cells.
Int. J. Mol. Med.
PUBLISHED: 03-09-2013
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Advanced oxidation protein products (AOPPs) as a novel marker of oxidative stress, are involved in a variety of diseases, including osteoporosis. Although a number of studies have shown the possible functions of AOPPs in biological processes, little is known about the role of AOPPs in the pathogenesis of osteoporosis. In this study, we aimed to investigate the effect of AOPPs on the proliferation and osteogenic differentiation of rat mesenchymal stem cells (MSCs). MSCs, isolated from bone marrow, were cultured in the absence or presence of AOPPs (50, 100, 200 and 400 mg/ml). MTT assay was used to determine the proliferative ability of the cells. Alkaline phosphatase (ALP) activity, the mRNA expression of ALP and collagen I and bone nodule formation were detected to assess osteogenic differentiation. Reactive oxygen species (ROS) generation was analyzed with the probe 2,7-dichlorodihydrofluorescein diacetate (DCFH-DA). The expression of receptor of advanced glycation end-products (RAGE) at the mRNA and protein level was detected by real-time PCR and western blot analysis, respectively. Compared with the control group, AOPPs inhibited MSC proliferation in a dose- and time-dependent manner. Moreover, AOPPs induced a significant reduction in ALP activity, as well as a decrease in ALP and collagen I mRNA levels in the MSCs; bone nodule formation was also inhibited. Furthermore, AOPPs increased ROS generation in the MSCs, and upregulated the expression of RAGE at the mRNA and protein level. These results suggest that AOPPs inhibit the proliferation and osteogenic differentiation of MSCs, possibly through the AOPPs-RAGE-ROS pathway; this may be an important mechanism in the development of osteoporosis.
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Effects of unfractionated heparin on renal osteodystrophy and vascular calcification in chronic kidney disease rats.
Bone
PUBLISHED: 02-21-2013
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Unfractionated heparin (UFH) is the most widely used anticoagulant in hemodialysis for chronic kidney disease (CKD) patients. Many studies have verified that UFH can induce bone loss in subjects with normal bone, but few have focused on its effect on renal osteodystrophy. We therefore investigated this issue in adenine-induced CKD rats. As CKD also impairs mineral metabolism systemically, we also studied the impacts of UFH on serum markers of CKD-mineral and bone disorder (CKD-MBD) and vascular calcification. We administered low and high doses of UFH (1U/g and 2U/g body weight, respectively) to CKD rats and compared them with CKD controls. At sacrifice, the serum markers of CKD-MBD did not significantly differ among the two UFH CKD groups and the CKD control group. The mean bone mineral densities (BMDs) of the total femur and a region of interest (ROI) constituted of trabecular and cortical bone were lower in the high-dose UFH (H-UFH) CKD group than in the CKD control group (P<0.05 and P<0.01, respectively). The BMD of the femoral ROI constituted of cortical bone did not differ between the H-UFH CKD group and the CKD control group. Histomorphometrical changes in the CKD rats indicated secondary hyperparathyroidism, and the femoral trabecular bone volume, but not cortical bone volume, significantly decreased with increasing UFH dose. The same decreasing trend was found in osteoblast parameters, and an increasing trend was found in osteoclast parameters; however, most differences were not significant. Moreover, no distinct statistical differences were found in the comparison of vascular calcium or phosphorus content among the CKD control group and the two UFH CKD groups. Therefore, we concluded that UFH could induce bone loss in CKD rats with secondary hyperparathyroidism, mainly by reducing the trabecular volume and had little effect on cortical bone volume. The underlying mechanism might involve inhibition of osteoblast activity and promotion of osteoclast activity by UFH. We did not find any effect of UFH on vascular calcification in CKD rats with secondary hyperparathyroidism.
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Endoplasmic reticulum stress signaling is involved in mitomycin C (MMC)-induced apoptosis in human fibroblasts via PERK pathway.
PLoS ONE
PUBLISHED: 02-13-2013
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Endoplasmic reticulum (ER) stress-mediated cell apoptosis has been implicated in various cell types, including fibroblasts. Previous studies have shown that mitomycin C (MMC)-induced apoptosis occurs in fibroblasts, but the effects of MMC on ER stress-mediated apoptosis in fibroblasts have not been examined. Here, MMC-induced apoptosis in human primary fibroblasts was investigated by exposing cells to a single dose of MMC for 5 minutes. Significant inhibition of cell proliferation and increased apoptosis were observed using a cell viability assay, Annexin V/propidium iodide double staining, cell cycle analysis, and TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling) staining. Upregulation of proapoptotic factors, including cleaved caspase-3 and poly ADP-ribose polymerase (PARP), was detected by Western blotting. MMC-induced apoptosis was correlated with elevation of 78-kDa glucose-regulated protein (GRP78) and C/EBP homologous protein (CHOP), which are hallmarks of ER stress. Three unfolded protein response (UPR) sensors (inositol-requiring enzyme 1, IRE1; activating transcription factor 6, ATF6; and PKR-like ER kinase, PERK) and their downstream signaling pathways were also activated. Knockdown of CHOP attenuated MMC-induced apoptosis by increasing the ratio of BCL-2/BAX and decreasing BIM expression, suggesting that ER stress is involved in MMC-induced fibroblast apoptosis. Interestingly, knockdown of PERK significantly decreased ER stress-mediated apoptosis by reducing the expression of CHOP, BIM and cleaved caspase-3. Reactive oxygen species (ROS) scavenging also decreased the expression of GRP78, phospho-PERK, CHOP, and BIM. These results demonstrate that MMC-induced apoptosis is triggered by ROS generation and PERK activation.
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The role of prophylactic transpapillary pancreatic stenting in distal pancreatectomy: a meta-analysis.
Front Med
PUBLISHED: 02-07-2013
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Pancreatic fistula (PF) is the most frequent complication after distal pancreatectomy (DP). Prophylactic transpapillary pancreatic stenting (PTPS) has been proposed recently for the prevention of PF after DP. In this meta-analysis, a comprehensive search was performed in the PubMed, Embase, and Cochrane Library databases. Studies analyzing the results of PTPS in DP were considered eligible for this meta-analysis. The analyzed outcome variables included PF rate, postoperative morbidity, non-PF-related complications, mortality, operation duration, and hospital stay. Four studies with 200 patients were included in this review. Only one was a randomized controlled trial (RCT). The results showed that PTPS was associated with less PF formation (odds ratio, 0.45; 95% confidence interval [CI], 0.22-0.94; P = 0.03) and shorter hospital stay (mean difference, - 6.31; 95% CI, - 6.99 to - 5.62; P < 0.00001). There was no significant difference in terms of the other variables. In conclusion, current evidence indicates that PTPS could reduce PF incidence and hospital stay after DP, without increasing other complications or operative time. However, the evidence is not solid, because the single RCT conflicted with the other three retrospective reports. Thus, considering the limitation, more well-designed RCTs on this topic are needed in the future.
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Mesenchymal stem cell-conditioned medium reduces liver injury and enhances regeneration in reduced-size rat liver transplantation.
J. Surg. Res.
PUBLISHED: 01-17-2013
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Mesenchymal stem cell (MSC) therapy can prevent parenchymal cell loss and promotes tissue repair through the action of trophic, secreted molecules. In this study, we investigated whether MSC-conditioned medium (MSC-CM) could protect hepatocytes and sinusoidal endothelial cells (SECs) and stimulate their regeneration in 50% reduced-size liver transplantation (RSLT).
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Primary repair of tetralogy of Fallot in infants: Transatrial/transpulmonary or transventricular approach.
Asian J Surg
PUBLISHED: 01-09-2013
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Right ventricular (RV) dysfunction is a significant cause of morbidity and mortality after surgical correction of tetralogy of Fallot (TOF). Transatrial/transpulmonary repair avoids a ventriculotomy (in contrast to the transventricular approach) in order to preserve the structure and function of the right ventricle. We performed a pilot prospective randomized controlled trial in infants with TOF undergoing primary repair.
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An acetylcholinesterase antibody-based quartz crystal microbalance for the rapid identification of spinal ventral and dorsal roots.
PLoS ONE
PUBLISHED: 01-01-2013
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Differences in the levels of acetylcholinesterase (AChE) in ventral and dorsal spinal roots can be used to differentiate the spinal nerves. Although many methods are available to assay AChE, a rapid and sensitive method has not been previously developed. Here, we describe an antibody-based quartz crystal microbalance (QCM) assay and its application for the quantification of AChE in the solutions of ventral and dorsal spinal roots. The frequency variation of the QCM device corresponds to the level of AChE over a wide dynamic range (0.5-10 µg/ml), which is comparable to the response range of the ELISA method. The frequency shift caused by the ventral roots is 3-fold greater than that caused by the dorsal roots. The antibody-based QCM sensor was stable across many successive replicate samples, and the method required less than 10 min, including the AChE extraction and analysis steps. This method is a rapid and convenient means for the quantification of AChE in biological samples and may be applicable for distinguishing the ventral and dorsal roots during surgical operations.
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Photoreceptor avascular privilege is shielded by soluble VEGF receptor-1.
Elife
PUBLISHED: 01-01-2013
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Optimal phototransduction requires separation of the avascular photoreceptor layer from the adjacent vascularized inner retina and choroid. Breakdown of peri-photoreceptor vascular demarcation leads to retinal angiomatous proliferation or choroidal neovascularization, two variants of vascular invasion of the photoreceptor layer in age-related macular degeneration (AMD), the leading cause of irreversible blindness in industrialized nations. Here we show that sFLT-1, an endogenous inhibitor of vascular endothelial growth factor A (VEGF-A), is synthesized by photoreceptors and retinal pigment epithelium (RPE), and is decreased in human AMD. Suppression of sFLT-1 by antibodies, adeno-associated virus-mediated RNA interference, or Cre/lox-mediated gene ablation either in the photoreceptor layer or RPE frees VEGF-A and abolishes photoreceptor avascularity. These findings help explain the vascular zoning of the retina, which is critical for vision, and advance two transgenic murine models of AMD with spontaneous vascular invasion early in life. DOI:http://dx.doi.org/10.7554/eLife.00324.001.
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The DNMT3B -579 G>T promoter polymorphism and risk of lung cancer.
Exp Ther Med
PUBLISHED: 08-31-2011
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The present study aimed to investigate the association of the -579 G>T polymorphism in the DNMT3B promoter with susceptibility to lung cancer. A total of 174 lung cancer patients and 135 healthy controls from the northern part of China were enrolled, and were matched for gender and age. All subjects were genotyped by polymerase chain reaction-restriction-fragment length polymorphism analysis and confirmed by DNA sequencing. Stratification analyses were used to study the subgroups of subjects by age and gender, and evaluate the association between the -579 G>T polymorphism and the genetic susceptibility to lung cancer. The results revealed that individuals with the DNMT3B -579 GT genotype had a significantly decreased risk of lung cancer [odds ratio (OR), 0.517; 95% confidence interval (CI), 0.273-0.981] compared with those with a -579 TT genotype in the studied population. However, the deviation was significant (OR, 0.138, 95% CI, 0.034-0.549) between the risk of lung cancer and the GT and GG genotype, when the smoking factor was considered. The data from this study indicate that the DNMT3B genetic polymorphism varies among various races, ethnic groups and geographical areas. The DNMT3B -579 G>T polymorphism may contribute to the genetic susceptibility to lung cancer.
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Are Helicobacter pylori and other Helicobacter species infection associated with human biliary lithiasis? A meta-analysis.
PLoS ONE
PUBLISHED: 08-23-2011
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Since the isolation of Helicobacter species in biliary system, a hypothetical question was raised about the role of these agents in the development of cholelithiasis. This meta-analysis is to explore the association between the Helicobacter infection and biliary lithiasis.
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Increased expression of multifunctional serine protease, HTRA1, in retinal pigment epithelium induces polypoidal choroidal vasculopathy in mice.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 08-15-2011
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Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in the elderly. Wet AMD includes typical choroidal neovascularization (CNV) and polypoidal choroidal vasculopathy (PCV). The etiology and pathogenesis of CNV and PCV are not well understood. Genome-wide association studies have linked a multifunctional serine protease, HTRA1, to AMD. However, the precise role of HTRA1 in AMD remains elusive. By transgenically expressing human HTRA1 in mouse retinal pigment epithelium, we showed that increased HTRA1 induced cardinal features of PCV, including branching networks of choroidal vessels, polypoidal lesions, severe degeneration of the elastic laminae, and tunica media of choroidal vessels. In addition, HTRA1 mice displayed retinal pigment epithelium atrophy and photoreceptor degeneration. Senescent HTRA1 mice developed occult CNV, which likely resulted from the degradation of the elastic lamina of Bruchs membrane and up-regulation of VEGF. Our results indicate that increased HTRA1 is sufficient to cause PCV and is a significant risk factor for CNV.
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Effects of matrine on proliferation and apoptosis in gallbladder carcinoma cells (GBC-SD).
Phytother Res
PUBLISHED: 08-14-2011
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Although matrine, a primary active component of dried Sophora flavescens root (ku shen), is known to induce apoptosis in a variety of tumor cells in vitro, the molecular mechanism of such apoptosis remains elusive. This analysis of the cell cycle and apoptosis in matrine-treated human gallbladder carcinoma cells (GBC-SD) showed that matrine can indeed inhibit cell proliferation and induce G1 cell cycle arrest and apoptosis in a dose- and time-dependent manner. An additional western blot analysis of matrine-treated cells also showed caspase-3 and Bcl-2 activation, as well as cyclinE down-regulation. Overall, the results indicate that matrine perturbs gallbladder cancer cell progression during the G1 phase by down-regulating cyclinE and induces apoptosis by decreasing the expression of the antiapoptotic protein Bcl-2 and increasing expression of the proapoptotic protein Bax.
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Structural basis for the neutralization and genotype specificity of hepatitis E virus.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-03-2011
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Hepatitis E virus (HEV) causes acute hepatitis in humans, predominantly by contamination of food and water, and is characterized by jaundice and flu-like aches and pains. To date, no vaccines are commercially available to prevent the disease caused by HEV. Previously, we showed that a monoclonal antibody, 8C11, specifically recognizes a neutralizing conformational epitope on HEV genotype I. The antibody 8C11 blocks the virus-like particle from binding to and penetrating the host cell. Here, we report the complex crystal structure of 8C11 Fab with HEV E2s(I) domain at 1.9 Å resolution. The 8C11 epitopes on E2s(I) were identified at Asp(496)-Thr(499), Val(510)-Leu(514), and Asn(573)-Arg(578). Mutations and cell-model assays identified Arg(512) as the most crucial residue for 8C11 interaction with and neutralization of HEV. Interestingly, 8C11 specifically neutralizes HEV genotype I, but not the other genotypes. Because HEV type I and IV are the most abundant genotypes, to understand this specificity further we determined the structure of E2s(IV) at 1.79 Å resolution and an E2s(IV) complex with 8C11 model was generated. The comparison between the 8C11 complexes with type I and IV revealed the key residues that distinguish these two genotypes. Of particular interest, the residue at amino acid position 497 at the 8C11 epitope region of E2s is distinct among these two genotypes. Swapping this residue from one genotype to another inversed the 8C11 reactivity, demonstrating the essential role played by amino acid 497 in the genotype recognition. These studies may lead to the development of antibody-based drugs for the specific treatment against HEV.
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What is Visualize?

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

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

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