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Find video protocols related to scientific articles indexed in Pubmed.
Proposed Motor Scoring System in a Porcine Model of Parkinson's Disease induced by Chronic Subcutaneous Injection of MPTP.
Exp Neurobiol
PUBLISHED: 07-18-2014
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Destruction of dopaminergic neurons in the substantia nigra pars compacta (SNpc) is a common pathophysiology of Parkinson's disease (PD). Characteristics of PD patients include bradykinesia, muscle rigidity, tremor at rest and disturbances in balance. For about four decades, PD animal models have been produced by toxin-induced or gene-modified techniques. However, in mice, none of the gene-modified models showed all 4 major criteria of PD. Moreover, distinguishing between PD model pigs and normal pigs has not been well established. Therefore, we planned to produce a pig model for PD by chronic subcutaneous administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), neurotoxin. Changes in behavioral patterns of pigs were thoroughly evaluated and a new motor scoring system was established for this porcine model that was based on the Unified Parkinson's Disease Rating Scale (UPDRS) in human PD patients. In summary, this motor scoring system could be helpful to analyze the porcine PD model and to confirm the pathology prior to further examinations, such as positron emission tomography-computed tomography (PET-CT), which is expensive, and invasive immunohistochemistry (IHC) of the brain.
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HeLa human cervical cancer cell migration is inhibited by treatment with dibutyryl-cAMP.
Anticancer Res.
PUBLISHED: 07-02-2014
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Cyclic AMP (cAMP) activates both protein kinase A (PKA) and guanine-nucleotide exchange factor exchange protein directly activated by CAMP (EPAC)-mediated Ras-related Protein1 (RAP1) GTPase that regulates various cellular functions including cell migration. Herein, we investigated whether cAMP-mediated PKA and EPAC1/RAP1 pathways differentially control HeLa cervical cancer cell migration. Although HeLa cell migration was reduced by dibutyryl-cAMP, we observed an increase in cAMP/PKA, cAMP/EPAC1/RAP1-GTPase, and RAC1-GTPase. HeLa cell migration and RAC1-GTPase were increased by treatment with 8-(4-chloro-phenylthio)-2'-O-methyladenosine-3',5'-cAMP analogue to activate EPAC-specific signaling pathways. When HeLa cells were treated with H-89, a PKA inhibitor, cell migration was enhanced but RAC1-GTPase was inhibited. In addition, cell migration induced by dibutyryl-cAMP was reversed but the activity of Rac1-GTPase was inhibited by H-89 treatment. Taken together, these data demonstrate that cAMP/PKA and cAMP/EPAC1/RAP1-GTPase might inversely control cervical cancer cell migration, although both signaling pathways may up-regulate RAC1-GTPase. It also suggests that cAMP-mediated cancer cell migration was independent of RAC1-GTPase activation.
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Effects of ethyl chloride spray on pain and parameters of needle electromyography in the upper extremity.
Am J Phys Med Rehabil
PUBLISHED: 06-01-2014
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The aim of this study was to compare the effects of ethyl chloride and placebo sprays for reducing pain induced by needle electromyography and changes in parameters of the motor unit action potential during needle electromyography of the upper extremity.
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Inhibitory effects of seaweed extracts on the growth of the vaginal bacterium Gardnerella vaginalis.
J Environ Biol
PUBLISHED: 05-13-2014
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Of 44 species of seaweed screened for potential anti-Gardnerella vaginalis activity, 27 (61.4%) showed antimicrobial activity by the agar disk-diffusion method. Among them, the strongest activities against the pathogen were exhibited by Chlorophyta, with Ulva pertusa producing an 11.3-mm zone of inhibition at 5 mg disk?¹. The MIC values of U. pertusa extracts against both G. vaginalis KCTC 5096 and KCTC 5097, the main cause of vaginosis, were 312 ?g ml?¹, while the MIC values against both Candida albicans KCTC 7270 and KCTC 7965, the main cause of candidiasis, were 2.5 mg ml?¹. Against Lactobacillus gasseri KCTC 3173 and Lactobacillus jensenii KCTC 5194, members of the normal vaginal microflora, no inhibitory effect was seen even at 10 mg ml?¹. To identify the primary active compounds, a U. pertusa powder was successively fractionated according to polarity, and the main active agents against G. vaginalis KCTC 5096 were determined to be nitrogenous compounds (156 ?g ml?¹ of the MIC value). According to these results, it was suggested that extracts of the seaweed U. pertusa are valuable for the development of natural therapeutic agents for treating women with bacterial vaginosis.
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Microarray and KOG analysis of Acanthamoeba healyi genes up-regulated by mouse-brain passage.
Exp. Parasitol.
PUBLISHED: 05-12-2014
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Long-term cultivation in a laboratory could reduce the virulence of Acanthamoeba. To identify virulence factors of Acanthamoeba, the authors compared the transcription profiles of long-term cultivated Acanthamoeba healyi (OLD) and three times mouse-brain passaged A. healyi (MBP) using microarray analysis and eukaryotic orthologous group (KOG) assignments. Microarray analysis revealed that 601 genes were up-regulated by mouse-brain passage. The results of real-time PCR of 8 randomly selected genes up-regulated in the MBP strain confirmed microarray analysis findings. KOG assignments showed relatively higher percentages of the MBP strain up-regulated genes in T article (signal transduction mechanism), O article (posttranslational modification, protein turnover, chaperones), C article (energy production and conversion), and J article (translation, ribosomal structure and biogenesis). In particular, the MBP strain showed higher expressions of cysteine protease and metalloprotease. A comparison of KOG assignments by microarray analysis and previous EST (expressed sequence tags) analysis showed similar populations of up-regulated genes. These results provide important information regarding the identification of virulence factors of pathogenic Acanthamoeba.
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Postoperative nausea and vomiting.
Korean J Anesthesiol
PUBLISHED: 05-08-2014
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Postoperative nausea and vomiting (PONV) is a long-standing issue, not a new concept in anesthesiology. Despite many studies over the last several decades, PONV remains a significant problem due to its complex mechanism. This review presents a summary of the mechanism underlying the pathogenesis of PONV, focusing on preventive treatment, particularly the use of new drugs. In addition, we discuss the latest meta-analysis results regarding correct clinical use of classic drugs. I also summarize the latest trends of postdischarge nausea and vomiting and the pharmacogenetics, which is attracting a great deal of attention from other medical fields in PONV-related studies. Finally, we discuss the drawbacks of existing studies on PONV and suggest a focus for future investigations.
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Depth profiles of methane oxidation potentials and methanotrophic community in a lab-scale biocover.
J. Biotechnol.
PUBLISHED: 05-08-2014
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The depth profiles of the CH4 oxidation potentials and the methanotrophic community were characterized in a lab-scale soil mixture biocover. The soil mixture samples were collected from the top (0-10cm), middle (10-40cm), and bottom (40-50cm) layers of the biocover where most of methane was oxidized at the top layer due to consumption of O2. Batch tests using serum bottles showed that the middle and bottom samples displayed CH4 oxidation activity under aerobic conditions, and their CH4 oxidation rates were 85 and 71% of the rate of top sample (8.40?molgdry sample(-1)h(-1)), respectively. The numbers of methanotrophs in the middle and bottom were not significantly different from those in the top sample. There was no statistical difference in the community stability indices (diversity and evenness) among the methanotrophic communities of the three layer samples, even though the community structures were distinguished from each other. Based on microarray analysis, type I and type II methanotrophs were equally present in the top sample, while type I was more dominant than type II in the middle and bottom samples. We suggested that the qualitative difference in the community structures was probably caused by the difference in the depth profiles of the CH4 and O2 concentrations. The results for the CH4 oxidation potential, methanotrophic biomass, and community stability indices in the middle and bottom layer samples indicated that the deeper layer in the methanotrophic biocover serves as a bioresource reservoir for sustainable CH4 mitigation.
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Videothoracoscopic management of a perforated central vein and pleura after ultrasound-guided internal jugular vein cannulation: a case report.
Korean J Anesthesiol
PUBLISHED: 04-28-2014
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A 23-year-old male underwent a left internal jugular vein catheterization during extended surgery for treatment of multiple fractures due to a traffic accident. Although the catheterization was performed under ultrasound (US) guidance, iatrogenic perforation of the central vein and pleura occurred. The catheter was removed, and the perforated site was addressed under thoracoscopy rather than an open thoracotomy. This case suggests that using US does not completely guarantee a complication-free outcome, and that catheter placement should be carefully confirmed. In addition, this case suggests that thoracoscopy may be an ideal method of resolving a perforation of the central vein and pleura.
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Control of functional responses via reversible oxygen loss in La?-xSrxFeO?-? films.
Adv. Mater. Weinheim
PUBLISHED: 04-16-2014
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La0.3 Sr0.7 FeO3-? films undergo dramatic changes in electronic and optical properties due to reversible oxygen loss induced by low-temperature heating. This mechanism to control the functional properties may serve as a platform for new devices or sensors in which external stimuli are used to dynamically control the composition of complex oxide heterostructures.
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The comparison of monitored anesthesia care with dexmedetomidine and spinal anesthesia during varicose vein surgery.
Ann Surg Treat Res
PUBLISHED: 04-08-2014
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The purpose of this study was to investigate the effectiveness and safety of monitored anesthesia care (MAC) using dexmedetomidine for its sedative and analgesic effect during varicose vein surgery.
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Cervical vertebral bone mineral density changes in adolescents during orthodontic treatment.
Am J Orthod Dentofacial Orthop
PUBLISHED: 04-01-2014
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The cervical vertebral maturation (CVM) stages have been used to estimate facial growth status. In this study, we examined whether cone-beam computed tomography images can be used to detect changes of CVM-related parameters and bone mineral density distribution in adolescents during orthodontic treatment.
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Seasonal variation of antibacterial activities in the green alga Ulva pertusa Kjellman.
J Environ Biol
PUBLISHED: 03-27-2014
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The present study was performed to screen out the extracts of algae and assess the seasonal variation in antimicrobial activity of Ulva pertusa against Gardnerella vaginalis. Seasonal variation in antibacterial activity was observed, with the extracts showing no activity during summer and autumn, and showing antibacterial activity from early winter (December) to middle spring (April). The maximum value of antimicrobial activity (6.5 mm inhibition zone at 5 mg disk(-1)) of U. pertusa against G. vaginalis was observed in April. Otherwise, for both chlorophyll a and b, the highest content (2.87 mg g(-1) and 1.37 mg g(-1)) was observed in March 2009. These results may reflect variation in cellular chemical compositions such as secondary metabolite(s) rather than chlorophyll and biological activities according to season.
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A Pilot Study for Discovering Candidate Genes of Chromosome 18q21 in Methamphetamine Abusers: Case-control Association Study.
Clin Psychopharmacol Neurosci
PUBLISHED: 03-01-2014
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It was previously suggested that the malic enzyme 2 (ME2) as the candidate gene for psychosis in fine mapping of chromosome 18q21. Chromosome 18q21 is also one of the possible regions that can contribute to addiction.
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Dexamethasone inhibits in vivo tumor growth by the alteration of bone marrow CD11b? myeloid cells.
Int. Immunopharmacol.
PUBLISHED: 02-09-2014
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Inflammation is closely associated with tumor growth, which is mediated by the activation of bone marrow-derived CD11b(+) cells. Here, we investigated whether anti-inflammatory dexamethasone (Dex), a synthetic glucocorticoid (GC), could regulate tumor growth and CD11b(+) myeloid bone marrow cells (BMCs) in lymphocyte (R1), monocyte (R2) and granulocyte (R3) regions of FSC-SSC dot plot. The growth of B16F10 mouse melanoma tumor was inhibited in Dex-injected group. Lung metastasis was decreased and the lifespan was elongated in Dex-injected mice with tumor resection. Intravenous injection of B16F10 cells increased the percentage of CD11b(+) myeloid BMCs in R1 and R2 regions from 3h to 72h. In contrast, little changes in the percentage of CD11b(+) myeloid BMCs were detected in R3 region. Among CD11b(+) myeloid BMCs, the percentage of CD11b(+)Gr-1(+) cells was increased in R1, R2 and R3 regions. Absolute number of CD11b(+) and CD11b(+)Gr-1(+) cells was enhanced in R1 region from 3h to 72 h. B16F10 tumor growth was significantly increased by intravenous injection of CD11b(+) BMCs. Tumor-bearing mice showed an increase in the percentage of CD11b(+) myeloid BMCs in R2 region and CD11b(+)Gr-1(+) cells in R2 and R3 regions, which are reduced by intravenous injection with Dex. Absolute number of CD11b(+)Gr-1(+) cells was enhanced in R2 and R3 regions. Tumor growth was significantly inhibited by intravenous injection of BMCs collected from Dex-treated tumor-bearing mice. Taken together, data demonstrate that tumor regression by Dex was resulted from the alteration of CD11b(+) myeloid BMCs and their inhibitory function to tumor growth. It suggests that CD11b(+) myeloid BMCs could regulate antitumor efficacy of GCs such as Dex.
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Fluorination of epitaxial oxides: synthesis of perovskite oxyfluoride thin films.
J. Am. Chem. Soc.
PUBLISHED: 01-30-2014
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While the synthesis of ABO3 perovskite films has enabled new strategies to control the functionality of this material class, the chemistries that have been realized in thin film form constitute only a fraction of those accessible to bulk chemists. Here, we report the synthesis of oxyfluoride films, where the incorporation of F may provide a new means to tune physical properties in thin films by modifying electronic structure. Fluorination is achieved by spin coating a poly(vinylidene fluoride) (PVDF) solution onto oxygen-deficient films. The film/polymer bilayer is then annealed, promoting the diffusion of F into the film. We have used this method to synthesize SrFeO(3-?)F? films, as confirmed by X-ray photoemission spectroscopy and X-ray absorption spectroscopy.
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Down-regulation of cellulose synthase inhibits the formation of endocysts in Acanthamoeba.
Korean J. Parasitol.
PUBLISHED: 01-28-2014
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Acanthamoeba cysts are resistant to unfavorable physiological conditions and various disinfectants. Acanthamoeba cysts have 2 walls containing various sugar moieties, and in particular, one third of the inner wall is composed of cellulose. In this study, it has been shown that down-regulation of cellulose synthase by small interfering RNA (siRNA) significantly inhibits the formation of mature Acanthamoeba castellanii cysts. Calcofluor white staining and transmission electron microscopy revealed that siRNA transfected amoeba failed to form an inner wall during encystation and thus are likely to be more vulnerable. In addition, the expression of xylose isomerase, which is involved in cyst wall formation, was not altered in cellulose synthase down-regulated amoeba, indicating that cellulose synthase is a crucial factor for inner wall formation by Acanthamoeba during encystation.
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Tobermolite effects on methane removal activity and microbial community of a lab-scale soil biocover.
J. Ind. Microbiol. Biotechnol.
PUBLISHED: 01-10-2014
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Three identical lab-scale biocovers were packed with an engineered soil (BC 1), tobermolite only (BC 2), and a mixture of the soil and tobermolite (BC 3), and were operated at an inlet load of 338-400 g-CH4 m(-2) d(-1) and a space velocity of 0.12 h(-1). The methane removal capacity was 293 ± 47 g-CH4 m(-2) d(-1) in steady state in the BC 3, which was significantly higher than those in the BC 1 and BC 2 (106 ± 24 and 114 ± 48 g-CH4 m(-2) d(-1), respectively). Quantitative PCR indicated that bacterial and methanotrophic densities (6.62-6.78 × 10(7) 16S rDNA gene copy number g-dry sample(-1) and 1.37-2.23 × 10(7) pmoA gene copy number g-dry sample(-1) in the BC 1 and BC 3, respectively) were significantly higher than those in the BC 2. Ribosomal tag pyrosequencing showed that methanotrophs comprised approximately 60 % of the bacterial community in the BC 2 and BC 3, while they only comprised 43 % in the BC 1. The engineered soil favored the growth of total bacteria including methanotrophs, while the presence of tobermolite enhanced the relative abundance of methanotrophs, resulting in an improved habitat for methanotrophs as well as greater methane mitigation performance in the mixture. Moreover, a batch experiment indicated that the soil and tobermolite mixture could display a stable methane oxidation level over wide temperature (20-40 °C, at least 38 ?mol g-dry sample(-1) h(-1)) and pH (5-8, at least 61 ?mol g-dry sample(-1) h(-1)) ranges. In conclusion, the soil and tobermolite mixture is promising for methane mitigation.
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The Actin-Sequestering Protein Thymosin Beta-4 Is a Novel Target of Hypoxia-Inducible Nitric Oxide and HIF-1? Regulation.
PLoS ONE
PUBLISHED: 01-01-2014
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The actin-sequestering protein thymosin beta-4 (T?4) is involved in various cellular and physiological processes such as proliferation, motility, growth and metastasis. Nitric oxide (NO) promotes tumor invasiveness and metastasis by activating various enzymes. Herein, we investigated whether hypoxia-inducible NO regulates T?4 expression and cancer cell migration using HeLa cervical cancer cells. NO production and T?4 expression were increased in a hypoxic condition. The treatment with N-(?-D-Glucopyranosyl)-N2-acetyl-S-nitroso-D, L-penicillaminamide (SNAP-1), to generate NO, enhanced the transcription of T?4 and cancer cell migration. SNAP-1-induced cell migration was decreased by the inhibition of T?4 with small interference (si) RNA. In a hypoxic condition, treatment with NG-monomethyl-L-arginine (L-NMMA), nitric oxide synthase (NOS) inhibitor, reduced T?4 transcriptional activity, and hypoxia-inducible factor (HIF)-1?. Hypoxia-induced cancer cell migration was also decreased by L-NMMA treatment. In a normoxic condition, T?4 transcriptional activity was decreased in the cells incubated in the presence of L-NMMA after co-transfection with T?4 promoter and GST-conjugated HIF-1?. Collectively, these results suggest that NO could regulate the expression of T?4 by direct or indirect effect of HIF-1? on T?4 promoter.
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Dynamic rearrangement of F-actin is required to maintain the antitumor effect of trichostatin A.
PLoS ONE
PUBLISHED: 01-01-2014
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Actin plays a role in various processes in eukaryotic cells, including cell growth and death. We investigated whether the antitumor effect of trichostatin A (TSA) is associated with the dynamic rearrangement of F-actin. TSA is an antitumor drug that induces hyper-acetylation of histones by inhibiting histone deacetylase. HeLa human cervical cancer cells were used to measure the antitumor effect of TSA. The percent cell survival was determined by an MTT assay. Hypodiploid cell formation was assessed by flow cytometry. Collapse of the mitochondrial membrane potential (MMP) was identified by a decrease in the percentage of cells with red MitoProbe J-aggregate (JC-1) fluorescence. Cell survival was reduced by treatment with TSA, as judged by an MTT assay and staining with propidium iodide, FITC-labeled annexin V, or 4',6-diamidino-2-phenylindole (DAPI). TSA also induced an MMP collapse, as judged by the measurement of intracellular red JC-1 fluorescence. In addition, the F-actin depolymerizers cytochalasin D (CytoD) and latrunculin B (LatB) induced an MMP collapse and increased apoptotic cell death in HeLa cells. However, our data show that apoptotic cell death and the MMP collapse induced by TSA were decreased by the co-treatment of cells with CytoD and LatB. These findings demonstrate that the dynamic rearrangement of F-actin might be necessary for TSA-induced HeLa cell apoptosis involving a TSA-induced MMP collapse. They also suggest that actin cytoskeleton dynamics play an important role in maintaining the therapeutic effects of antitumor agents in tumor cells. They further suggest that maintaining the MMP could be a novel strategy for increasing drug sensitivity in TSA-treated tumors.
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Cancer incidence and survival among adolescents and young adults in Korea.
PLoS ONE
PUBLISHED: 01-01-2014
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In Korea, cancer is the third leading cause of death among adolescents and young adults (AYAs). However, cancer incidence and survival trends among AYAs (15-29 years) have never been studied in Korea. Therefore, this study aimed to investigate the incidence and relative survival rates and their trends among AYAs in Korea.
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Brain-metastatic Triple-negative Breast Cancer Cells Regain Growth Ability by Altering Gene Expression Patterns.
Cancer Genomics Proteomics
PUBLISHED: 12-17-2013
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Backgroud/Aim: Triple-negative breast cancer (TNBC) frequently metastasizes to the brain (BrM). However, genes responsible for BrM of TNBC are yet to be identified.
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The usefulness of F-18 FDG PET/CT-mammography for preoperative staging of breast cancer: comparison with conventional PET/CT and MR-mammography.
Radiol Oncol
PUBLISHED: 12-01-2013
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The objective of the study was to compare the diagnostic efficacy of an integrated Fluorine-18 fluorodeoxyglucose (F-18 FDG) PET/CT-mammography (mammo-PET/CT) with conventional torso PET/CT (supine-PET/CT) and MR-mammography for initial assessment of breast cancer patients.
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Non-fermi-liquid and topological States with strong spin-orbit coupling.
Phys. Rev. Lett.
PUBLISHED: 11-12-2013
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We argue that a class of strongly spin-orbit-coupled materials, including some pyrochlore iridates and the inverted band gap semiconductor HgTe, may be described by a minimal model consisting of the Luttinger Hamiltonian supplemented by Coulomb interactions, a problem studied by Abrikosov and collaborators. It contains twofold degenerate conduction and valence bands touching quadratically at the zone center. Using modern renormalization group methods, we update and extend Abrikosovs classic work and show that interactions induce a quantum critical non-Fermi-liquid phase, stable provided time-reversal and cubic symmetries are maintained. We determine the universal power-law exponents describing various observables in this Luttinger-Abrikosov-Beneslavskii state, which include conductivity, specific heat, nonlinear susceptibility, and the magnetic Gruneisen number. Furthermore, we determine the phase diagram in the presence of cubic and/or time-reversal symmetry breaking perturbations, which includes a topological insulator and Weyl semimetal phases. Many of these phases possess an extraordinarily large anomalous Hall effect, with the Hall conductivity scaling sublinearly with magnetization ?_{xy}?M^{0.51}.
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Riluzole attenuates neuropathic pain and enhances functional recovery in a rodent model of cervical spondylotic myelopathy.
Neurobiol. Dis.
PUBLISHED: 10-04-2013
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Cervical spondylotic myelopathy (CSM) is the commonest cause of spinal cord impairment worldwide and despite surgical treatment, it is commonly associated with chronic neuropathic pain and neurological impairment. Based on data suggesting a key role of sodium and glutamate mediated cellular injury in models of spinal cord compression, we examined whether riluzole, a sodium channel/glutamate blocker, could improve neurobehavioral outcomes in a rat model of CSM. To produce chronic progressive compression of the cervical spinal cord, we used an established model of graded mechanical cord compromise developed in our laboratory. The chronic (8weeks) mechanical compression of the cervical spinal cord resulted in persistent mechanical allodynia and thermal hyperalgesia at 8weeks. Moreover, we found increased expression of phosphorylated NR1 and NR2B in the dorsal horns as well as astrogliosis and increased microglia expression in the dorsal horns after mechanical compression. Following daily systemic administration for 7weeks after the induction of compression, riluzole (8mg/kg) significantly attenuated forelimb and hindlimb mechanical allodynia and alleviated thermal hyperalgesia in the tail. Importantly, riluzole led to a decrease in swing phase duration, an increase in hind leg swing speed and an increase paw intensity in gait analysis. Riluzole also decreased the number of phosphorylated NR1 and phosphorylated NR2B positive cells in the dorsal horns and the microglia activation in the dorsal horns. Together, our results indicate that systemic riluzole administration during chronic cervical spinal cord compression is effective at protecting spinal cord tissue, preserving neurobehavioral function and alleviating neuropathic pain, possibly by decreasing NMDA receptor phosphorylation in astrocytes and by eliminating microglia activation. As such, riluzole represents a promising clinical treatment for CSM.
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The presence of significant methylotrophic population in biological activated carbon of a full-scale drinking water plant.
J. Microbiol. Biotechnol.
PUBLISHED: 09-05-2013
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Methylotrophs within biological activated carbon (BAC) systems have not received attention although they are a valuable biological resource for degradation of organic pollutants. In this study, methylotrophic populations were monitored for four consecutive seasons in BAC of an actual drinking water plant, using ribosomal tag pyrosequencing. Methylotrophs constituted up to 5.6% of the bacterial community, and the methanotrophs Methylosoma and Methylobacter were most abundant. Community comparison showed that the temperature was an important factor affecting community composition, since it had an impact on the growth of particular methylotrophic genera. These results demonstrated that BAC possesses a substantial methylotrophic activity and harbors the relevant microbes.
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A new method for measurement of the vitrification rate of earthenware texture by scanning electron microscope.
Microsc. Microanal.
PUBLISHED: 08-08-2013
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A new method for determining the vitrification rate of pottery depending on the firing temperature was devised using secondary electron images (SEI) of scanning electron microscope (SEM). Several tests were performed to establish the appropriate operating conditions of SEM and reproducibility as well as to examine the applicability of the method. The grayscale values converted from each pixel of SEI were used to determine the vitrification rate of pottery, which in our study were artificially fired specimens composed of three types of clay. A comparison between the vitrification rate value and appearance temperature of minerals shows that mullite formation starts at 1,100°C, during which the vitrification rate rapidly increases by over 10%. In consequence, the result presented here demonstrates that the new method can be applied to estimate the firing temperature of pottery.
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Anabolic effects of Peniel 2000, a peptide that regulates TGF-?1 signaling on intervertebral disc degeneration.
Spine
PUBLISHED: 07-03-2013
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An in vitro study with bovine intervertebral disc (IVD) cells and an in vivo study with a rabbit disc degeneration model on the extracellular matrix metabolism by a biglycan-derived peptide (Peniel 2000; P2K).
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Identification of atg8 isoform in encysting acanthamoeba.
Korean J. Parasitol.
PUBLISHED: 06-26-2013
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Autophagy-related protein 8 (Atg8) is an essential component of autophagy formation and encystment of cyst-forming parasites, and some protozoa, such as, Acanthamoeba, Entamoeba, and Dictyostelium, have been reported to possess a type of Atg8. In this study, an isoform of Atg8 was identified and characterized in Acanthamoeba castellanii (AcAtg8b). AcAtg8b protein was found to encode 132 amino acids and to be longer than AcAtg8 protein, which encoded 117 amino acids. Real-time PCR analysis showed high expression levels of AcAtg8b and AcAtg8 during encystation. Fluorescence microscopy demonstrated that AcAtg8b is involved in the formation of the autophagosomal membrane. Chemically synthesized siRNA against AcAtg8b reduced the encystation efficiency of Acanthamoeba, confirming that AcAtg8b, like AcAtg8, is an essential component of cyst formation in Acanthamoeba. Our findings suggest that Acanthamoeba has doubled the number of Atg8 gene copies to ensure the successful encystation for survival when 1 copy is lost. These 2 types of Atg8 identified in Acanthamoeba provide important information regarding autophagy formation, encystation mechanism, and survival of primitive, cyst-forming protozoan parasites.
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Incidence of cervical, endometrial, and ovarian cancer in Korea, 1999-2010.
J Gynecol Oncol
PUBLISHED: 06-26-2013
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To investigate the recent incidence of and trends in cervical, endometrial, and ovarian cancer in Korean females.
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TRAIL negatively regulates VEGF-induced angiogenesis via caspase-8-mediated enzymatic and non-enzymatic functions.
Angiogenesis
PUBLISHED: 04-09-2013
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Solid tumors supply oxygen and nutrients required for angiogenesis by producing vascular endothelial growth factor (VEGF). Thus, inhibitors of VEGF signaling abrogate tumor angiogenesis, resulting in the suppression of tumor growth and metastasis. We here investigated the effects of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on VEGF-induced angiogenesis. TRAIL inhibited VEGF-induced in vitro angiogenesis of human umbilical vein endothelial cells (HUVECs) and in vivo neovascularization in chicken embryos and mice. TRAIL blocked VEGF-induced angiogenic signaling by inhibiting ERK, Src, FAK, paxillin, Akt, and eNOS. Further, TRAIL blocked intracellular Ca(2+) elevation and actin reorganization in HUVECs stimulated with VEGF, without inhibiting VEGF receptor-2 tyrosine phosphorylation. TRAIL increased caspase-8 activity, without inducing caspase-9/-3 activation and apoptosis. Moreover, TRAIL resulted in cleavage of FAK into FAK-related non-kinase-like fragments in VEGF-stimulated HUVECs, which was blocked by a caspase-8 inhibitor and cellular caspase-8-like inhibitory protein. Biochemical and pharmacological inhibition of caspase-8 and FAK blocked the inhibitory effects of TRAIL on VEGF-stimulated anti-angiogenic signaling and events. In addition, caspase-8 knockdown also suppressed VEGF-mediated signaling and angiogenesis, suggesting that procaspase-8 plays a role of a non-apoptotic modulator in VEGF-induced angiogenic signaling. These results suggest that TRAIL inhibits VEGF-induced angiogenesis by increasing caspase-8 activity and subsequently decreasing non-apoptotic signaling functions of procaspase-8, without inducing caspase-3 activation and endothelial cell cytotoxicity. These data indicate that caspase-8 may be used as an anti-angiogenic drug for solid tumors resistant to TRAIL and anti-tumor drugs.
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The inhibitory activities of the edible green alga Capsosiphon fulvescens on rat lens aldose reductase and advanced glycation end products formation.
Eur J Nutr
PUBLISHED: 03-28-2013
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PURPOSE: Accumulating evidence suggests that inhibitors of aldose reductase (AR) may prevent hyperglycemia-induced long-term complications in diabetes mellitus. In the present study, we evaluated the AR inhibitory potential of ethanolic (EtOH) extracts from 22 seaweed species. METHODS: AR inhibitory activities of the selected seaweed species were evaluated using the rat lens aldose reductase (RLAR) inhibitory assay. RESULTS: All extracts exhibited RLAR inhibitory activity, which ranged from 5.87 to 92.71 % at a concentration of 50 ?g/mL. Since Capsosiphon fulvescens exhibited significant inhibitory potential and is a frequently used foodstuff, it was selected for a detailed investigation using RLAR and advanced glycation end products (AGE) formation inhibitory assays. Among the different solvent-soluble fractions, the CH2Cl2, EtOAc, and n-BuOH fractions showed promising RLAR and AGE formation inhibitory activities. Considering the AR inhibitory potential, CH2Cl2 and EtOAc fractions were selected for chromatographic separation and yielded 11 compounds in which capsofulvesin A, capsofulvesin B, and chalinasterol showed potential RLAR inhibitory activity with the respective IC50 values of 52.53, 101.92, and 345.27 ?M. Kinetic studies revealed that capsofulvesin A and chalinasterol exhibited mixed type inhibition, while capsofulvesin B exhibited noncompetitive inhibition. To our knowledge, this is the first report of AR inhibitory activity of the glycolipids capsofulvesin A and capsofulvesin B. CONCLUSIONS: Our results clearly indicate the potential RLAR and AGE formation inhibitory activities of C. fulvescens as well as its isolated constituents, which could be further explored to develop therapeutic modalities for the treatment of diabetes and related complications.
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Ethanol induces cell cycle arrest and triggers apoptosis via Sp1-dependent p75NTR expression in human neuroblastoma cells.
Cell Biol. Toxicol.
PUBLISHED: 03-26-2013
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Ethanol exposure has deleterious effects on the central nervous system. Although several mechanisms for ethanol-induced damage have been suggested, the precise mechanism underlying ethanol-induced neuronal cell death remains unclear. Recent studies indicate that the p75 neurotrophin receptor (p75NTR) has a critical role in the regulation of neuronal survival. This study was designed to examine the role of p75NTR in ethanol-induced apoptotic signaling in neuroblastoma cells. Ethanol caused highly increased level of p75NTR expression. The use of small interfering RNA to inhibit p75NTR expression markedly attenuated ethanol-induced cell cycle arrest and apoptosis. DNA binding activity of Sp1 was increased by ethanol, whereas inhibition of Sp1 activity by mithramycin, a Sp1 inhibitor, or short hairpin RNA suppressed ethanol-induced p75NTR expression. In addition, inhibitors of casein kinase 2 (CK2) and extracellular signal-regulated kinase (ERK) augmented ethanol-induced p75NTR expression. Our results also demonstrate that inhibition of ERK and CK2 caused a further increase in the activation of the p75NTR proximal promoter induced by ethanol. This increased activation was partially suppressed by the deletion of the Sp1 binding sites. These results suggest that Sp1-mediated p75NTR expression is regulated at least in part by ERK and CK2 pathways. The present study also showed that treatment with ethanol resulted in significant increases in the expression of p21, but not the levels of p53 and p53 target genes such as Bax, Puma, and Bcl-2. Furthermore, the inhibition of p75NTR expression or Sp1 activity suppressed ethanol-induced p21 expression, cell cycle arrest, and apoptosis. These data suggest that ethanol increases p75NTR expression, and CK2 and ERK signaling inversely regulate Sp1-mediated p75NTR expression in ethanol-treated neuroblastoma cells. Thus, our study provides more insight into the mechanisms underlying ethanol actions.
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Amnestic multiple cognitive domains impairment and periventricular white matter hyperintensities are independently predictive factors progression to dementia in mild cognitive impairment.
Int J Geriatr Psychiatry
PUBLISHED: 03-15-2013
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Mild cognitive impairment (MCI) usually represents a transitional phase between normal cognitive function and dementia, but not all people with MCI develop dementia because MCI is a clinically and etiologically heterogeneous grouping. The aim of this study was to determine whether clinical subtypes of MCI and severity of white matter hyperintensities (WMH) were associated with progression of MCI to dementia.
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Does medial support decrease major complications of unstable proximal humerus fractures treated with locking plate?
BMC Musculoskelet Disord
PUBLISHED: 03-13-2013
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The purpose of this study was to evaluate the role of medial support and clinical factors responsible on outcomes and major complications associated with treatment of unstable proximal humerus fractures using a locking plate and suture augmentation.
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B cell activating factor-dependent expression of vascular endothelial growth factor in MH7A human synoviocytes stimulated with tumor necrosis factor-?.
Int. Immunopharmacol.
PUBLISHED: 02-28-2013
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Angiogenesis in rheumatoid arthritis (RA) is one of the histological hallmarks, which is mediated by expression of vascular endothelial growth factor (VEGF) in RA synovium. VEGF expression is enhanced by TNF-?, the main pro-inflammatory cytokine in RA. B cell activating factor (BAFF) which plays a role in maturation and maintenance of B cells is also associated with autoimmune RA. Here, we investigated whether BAFF could regulate VEGF expression in TNF-?-stimulated synovium using MH7A synovial cells that are established by transfection with the SV40 T antigen. Changes in hBAFF and hVEGF were measured by western blotting, RT-PCR and luciferase promoter assay. When MH7A cells were treated with TNF-?, we observed that TNF-? increased the expression of hBAFF and hVEGF. TNF-? also increased transcriptional activity of hBAFF and hVEGF as judged by luciferase promoter assay. Inhibition of hBAFF expression with BAFF-siRNA decreased transcriptional level and activity of hVEGF. In addition, when c-fos expression was inhibited by the transfection of MH7A cells with c-fos-siRNA, data showed that transcriptional level and activity of both hBAFF and hVEGF were attenuated by the activation with TNF-?. Our results demonstrate for the first time that VEGF-mediated angiogenesis in RA could be controlled by TNF-?-induced BAFF expression through c-Fos. Data suggest that TNF-?-induced BAFF expression and BAFF-mediated VEGF expression in synovium may cooperate to maintain the capacity of such cells to protect B cells from apoptosis and the supply of nutrients and oxygen in inflammatory microenvironments.
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Theory of topological quantum phase transitions in 3D noncentrosymmetric systems.
Phys. Rev. Lett.
PUBLISHED: 02-19-2013
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We construct a general theory describing the topological quantum phase transitions in 3D systems with broken inversion symmetry. While the consideration of the systems codimension generally predicts the appearance of a stable metallic phase between the normal and topological insulators, it is shown that a direct topological phase transition between two insulators is also possible when an accidental band crossing occurs along directions with high crystalline symmetry. At the quantum critical point, the energy dispersion becomes quadratic along one direction while the dispersions along the other two orthogonal directions are linear, which manifests the zero chirality of the band touching point. Because of the anisotropic dispersion at quantum critical point, various thermodynamic and transport properties show unusual temperature dependence and anisotropic behaviors.
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Cysteine protease inhibitor (AcStefin) is required for complete cyst formation of Acanthamoeba.
Eukaryotic Cell
PUBLISHED: 02-08-2013
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The encystation of Acanthamoeba leads to the formation of resilient cysts from vegetative trophozoites. This process is essential for parasite survival under unfavorable conditions, such as those associated with starvation, low temperatures, and biocides. Furthermore, cysteine proteases have been implicated in the massive turnover of intracellular components required for encystation. Thus, strict modulation of the activities of cysteine proteases is required to protect Acanthamoeba from intracellular damage. However, mechanisms underlying the control of protease activity during encystation have not been established in Acanthamoeba. In the present study, we identified and characterized Acanthamoeba cysteine protease inhibitor (AcStefin), which was found to be highly expressed during encystation and to be associated with lysosomes by fluorescence microscopy. Recombinant AcStefin inhibited various cysteine proteases, including human cathepsin B, human cathepsin L, and papain. Transfection with small interfering RNA against AcStefin increased cysteine protease activity during encystation and resulted in incomplete cyst formation, reduced excystation efficiency, and a significant reduction in cytoplasmic area. Taken together, these results indicate that AcStefin is involved in the modulation of cysteine proteases and that it plays an essential role during the encystation of Acanthamoeba.
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A novel experimental model of cervical spondylotic myelopathy (CSM) to facilitate translational research.
Neurobiol. Dis.
PUBLISHED: 02-01-2013
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Cervical spondylotic myelopathy (CSM) is the most common form of spinal cord impairment in adults. However critical gaps in our knowledge of the pathobiology of this disease have limited therapeutic advances. To facilitate progress in the field of regenerative medicine for CSM, we have developed a unique, clinically relevant model of CSM in rats. To model CSM, a piece of synthetic aromatic polyether, to promote local calcification, was implanted microsurgically under the C6 lamina in rats. We included a sham group in which the material was removed 30s after the implantation. MRI confirmed postero-anterior cervical spinal cord compression at the C6 level. Rats modeling CSM demonstrated insidious development of a broad-based, ataxic, spastic gait, forelimb weakness and sensory changes. No neurological deficits were noted in the sham group during the course of the study. Spasticity of the lower extremities was confirmed by a significantly greater H/M ratio in CSM rats in H reflex recordings compared to sham. Rats in the compression group experienced significant gray and white matter loss, astrogliosis, anterior horn cell loss and degeneration of the corticospinal tract. Moreover, chronic progressive posterior compression of the cervical spinal cord resulted in compromise of the spinal cord microvasculature, blood-spinal cord barrier disruption, inflammation and activation of apoptotic signaling pathways in neurons and oligodendrocytes. Finally, CSM rats were successfully subjected to decompressive surgery as confirmed by MRI. In summary, this novel rat CSM model reproduces the chronic and progressive nature of human CSM, produces neurological deficits and neuropathological features accurately mimicking the human condition, is MRI compatible and importantly, allows for surgical decompression.
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Analysis of single nucleotide polymorphism in adolescent idiopathic scoliosis in Korea: for personalized treatment.
Yonsei Med. J.
PUBLISHED: 02-01-2013
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The incidence of adolescent idiopathic scoliosis (AIS) has rapidly increased, and with it, physician consultations and expenditures (about one and a half times) in the last 5 years. Recent etiological studies reveal that AIS is a complex genetic disorder that results from the interaction of multiple gene loci and the environment. For personalized treatment of AIS, a tool that can accurately measure the progression of Cobbs angle would be of great use. Gene analysis utilizing single nucleotide polymorphism (SNP) has been developed as a diagnostic tool for use in Caucasians but not Koreans. Therefore, we attempted to reveal AIS-related genes and their relevance in Koreans, exploring the potential use of gene analysis as a diagnostic tool for personalized treatment of AIS therein.
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Combined treatment with peroxisome proliferator-activated receptor (PPAR) gamma ligands and gamma radiation induces apoptosis by PPAR?-independent up-regulation of reactive oxygen species-induced deoxyribonucleic acid damage signals in non-small cell lung
Int. J. Radiat. Oncol. Biol. Phys.
PUBLISHED: 01-17-2013
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To investigate possible radiosensitizing activities of the well-known peroxisome proliferator-activated receptor (PPAR)? ligand ciglitazone and novel PPAR? ligands CAY10415 and CAY10506 in non-small cell lung cancer (NSCLC) cells.
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Cyclin-dependent kinase 4 signaling acts as a molecular switch between syngenic differentiation and neural transdifferentiation in human mesenchymal stem cells.
Cell Cycle
PUBLISHED: 01-16-2013
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Multipotent mesenchymal stem/stromal cells (MSCs) are capable of differentiating into a variety of cell types from different germ layers. However, the molecular and biochemical mechanisms underlying the transdifferentiation of MSCs into specific cell types still need to be elucidated. In this study, we unexpectedly found that treatment of human adipose- and bone marrow-derived MSCs with cyclin-dependent kinase (CDK) inhibitor, in particular CDK4 inhibitor, selectively led to transdifferentiation into neural cells with a high frequency. Specifically, targeted inhibition of CDK4 expression using recombinant adenovial shRNA induced the neural transdifferentiation of human MSCs. However, the inhibition of CDK4 activity attenuated the syngenic differentiation of human adipose-derived MSCs. Importantly, the forced regulation of CDK4 activity showed reciprocal reversibility between neural differentiation and dedifferentiation of human MSCs. Together, these results provide novel molecular evidence underlying the neural transdifferentiation of human MSCs; in addition, CDK4 signaling appears to act as a molecular switch from syngenic differentiation to neural transdifferentiation of human MSCs.
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Phosphodiesterase inhibitors control A172 human glioblastoma cell death through cAMP-mediated activation of protein kinase A and Epac1/Rap1 pathways.
Life Sci.
PUBLISHED: 09-06-2011
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We investigated whether cAMP-mediated protein kinase A(PKA) and Epac1/Rap1 pathways differentially affect brain tumor cell death using 4-(3-cyclopentyloxy-4-methoxyphenyl)-2-pyrrolidone(rolipram), specific phosphodiesterase type IV(PDE IV) inhibitor.
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Expression of SDF-1? and leptin, and their effect on expression of angiogenic factors in mouse ovaries.
Clin Exp Reprod Med
PUBLISHED: 08-08-2011
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Ovarian angiogenesis plays an important role in folliculogenesis. However, little is known about the expression of angiogenic factors during follicular development according to female age. Stromal cell derived factor-1? (SDF-1?) plays a role in granulosa cell survival and embryo quality as an angiogenic chemokine. Leptin is also involved in folliculogenesis and angiogenesis. This study examined expression of SDF-1? and leptin, and their effects on the expression of angiogenic factors in the ovary during follicular development according to female age.
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Protein tyrosine phosphatase 1B and ?-glucosidase inhibitory Phlorotannins from edible brown algae, Ecklonia stolonifera and Eisenia bicyclis.
Biosci. Biotechnol. Biochem.
PUBLISHED: 08-07-2011
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The present work investigates protein tyrosine phosphatase 1B (PTP1B) and the ?-glucosidase inhibitory activities of two edible brown algae, Ecklonia stolonifera and Eisenia bicyclis, as well as in their isolated phlorotannins. Since the individual extracts and fractions showed significant inhibitory activities, column chromatography was performed to isolate six phlorotannins, phloroglucinol (1), dioxinodehydroeckol (2), eckol (3), phlorofurofucoeckol-A (4), dieckol (5), and 7-phloroeckol (6). Phlorotannins 3-6 were potent and noncompetitive PTP1B inhibitors with IC(50) values ranging from 0.56 to 2.64 µM; 4-6 exhibited the most potent ?-glucosidase inhibition with IC(50) values ranging from 1.37 to 6.13 µM. Interestingly, 4 and 6 were noncompetitive, while 5 exhibited competitive inhibition in an ?-glucosidase assay. E. stolonifera and E. bicyclis as well as their isolated phlorotannins therefore possessed marked PTP1B and ?-glucosidase inhibitory activities; this could lead to opportunities in the development of therapeutic agents to control the postprandial blood glucose level and thereby prevent diabetic complications.
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Reduction of perchlorate by salt tolerant bacterial consortia.
Bioresour. Technol.
PUBLISHED: 08-04-2011
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Two perchlorate-reducing bacterial consortia (PRBC) were obtained by enrichment cultures from polluted marine sediments. Non-salt-tolerant PRBC (N-PRBC) was enriched without the addition of NaCl, and salt tolerant-PRBC (ST-PRBC) was enriched with 30 g-NaCl L(-1). Although the perchlorate reduction rates decreased with increasing NaCl concentration, ST-PRBC (resp., N-PRBC) could reduce perchlorate until 75 g-NaCl L(-1) (resp., 30 g-NaCl L(-1)). The reduction yield (1.34±0.05 mg-perchlorate per mg-acetate) and maximum perchlorate reduction rate (86 mg-perchlorateL(-1) h(-1)) of ST-PRBC was higher than those (1.16±0.03 mg-perchlorate per mg-acetate and 48 mg-perchlorate L(-1) h(-1)) of N-PRBC. Kinetic analysis showed that NaCl acted as an uncompetitive inhibitor against both PRBCs. The inhibition constants were 25 and 41 mg-NaCl L(-1) for N-PRBC and ST-PRBC, respectively.
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Microarray analysis of differentially expressed genes between cysts and trophozoites of Acanthamoeba castellanii.
Korean J. Parasitol.
PUBLISHED: 07-28-2011
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Acanthamoeba infection is difficult to treat because of the resistance property of Acanthamoeba cyst against the host immune system, diverse antibiotics, and therapeutic agents. To identify encystation mediating factors of Acanthamoeba, we compared the transcription profile between cysts and trophozoites using microarray analysis. The DNA chip was composed of 12,544 genes based on expressed sequence tag (EST) from an Acanthamoeba ESTs database (DB) constructed in our laboratory, genetic information of Acanthamoeba from TBest DB, and all of Acanthamoeba related genes registered in the NCBI. Microarray analysis indicated that 701 genes showed higher expression than 2 folds in cysts than in trophozoites, and 859 genes were less expressed in cysts than in trophozoites. The results of real-time PCR analysis of randomly selected 9 genes of which expression was increased during cyst formation were coincided well with the microarray results. Eukaryotic orthologous groups (KOG) analysis showed an increment in T article (signal transduction mechanisms) and O article (posttranslational modification, protein turnover, and chaperones) whereas significant decrement of C article (energy production and conversion) during cyst formation. Especially, cystein proteinases showed high expression changes (282 folds) with significant increases in real-time PCR, suggesting a pivotal role of this proteinase in the cyst formation of Acanthamoeba. The present study provides important clues for the identification and characterization of encystation mediating factors of Acanthamoeba.
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Characterization of methane oxidation by a methanotroph isolated from a landfill cover soil, South Korea.
J. Microbiol. Biotechnol.
PUBLISHED: 07-28-2011
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A methane-oxidizing bacterium was isolated from the enriched culture of a landfill cover soil. The closest relative of the isolate, designated M6, is Methylocystis sp. Based on a kinetic analysis, the maximum specific methane oxidation rate and saturation constant were 4.93 mmol·g--dry cell weight--1·h?¹ and 23 microM, respectively. This was the first time a kinetic analysis was performed using pure methanotrophic culture. The methane oxidation by M6 was investigated in the presence of aromatic (m- and p-xylene and ethylbenzene) or sulfur (hydrogen sulfide, dimethyl sulfide, methanthiol) compounds. The methane oxidation was inhibited by the presence of aromatic or sulfur compounds.
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Stereocalpin A inhibits the expression of adhesion molecules in activated vascular smooth muscle cells.
Int. Immunopharmacol.
PUBLISHED: 07-26-2011
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Up-regulation of cell adhesion molecules on vascular smooth muscle cells (VSMCs) and leukocyte recruitment to the vascular wall contribute to vascular inflammation and atherosclerosis. Stereocalpin A, a chemical compound of the Antarctic lichen Ramalina terebarata, displays tumoricidal activity against several different tumor cell types. However, other biological activities of stereocalpin A and its molecular mechanisms remain unknown. In this study, our work is directed toward studying the in vitro effects of stereocalpin A on the ability to suppress the expression of adhesion molecules induced by TNF-? in vascular smooth muscle cells. Pretreatment of VSMCs for 2h with stereocalpin A at nontoxic concentrations of 0.1-10 ?g/ml inhibited TNF-?-induced adhesion of THP-1 monocytic cells and expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1). Stereocalpin A reduced TNF-?-induced production of intracellular reactive oxygen species (ROS) and phosphorylation of p38, ERK, JNK and Akt. Stereocalpin A also inhibited NK-?B activation induced by TNF-?. Moreover, stereocalpin A inhibited TNF-?-induced ??? kinase activation, subsequent degradation of ????, and nuclear translocation of NF-?B. Hence, we describe a new anti-inflammatory activity and mechanism of stereocalpin A, owing to the negative regulation of TNF-?-induced adhesion molecule and MCP-1 expression, monocyte adhesion and ROS production in vascular smooth muscle cells. These results suggest that stereocalpin A has the potential to exert a protective effect by modulating inflammation within the atherosclerotic lesion.
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Sulforaphane suppresses vascular adhesion molecule-1 expression in TNF-?-stimulated mouse vascular smooth muscle cells: involvement of the MAPK, NF-?B and AP-1 signaling pathways.
Vascul. Pharmacol.
PUBLISHED: 07-04-2011
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Atherosclerosis is a long-term inflammatory disease of the arterial wall. Increased expression of the cell adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) is associated with increased proliferation of vascular smooth muscle cells (VSMCs), leading to increased neointima or atherosclerotic lesion formation. Therefore, the functional inhibition of adhesion molecules could be a critical therapeutic target of inflammatory disease. In the present study, we investigate the effect of sulforaphane on the expression of VCAM-1 induced by TNF-? in cultured mouse vascular smooth muscle cell lines. Pretreatment of VSMCs for 2h with sulforaphane (1-5?g/ml) dose-dependently inhibited TNF-?-induced adhesion of THP-1 monocytic cells and protein expression of VCAM-1. Sulforaphane also suppressed TNF-?-induced production of intracellular reactive oxygen species (ROS) and activation of p38, ERK and JNK. Furthermore, sulforaphane inhibited NK-?B and AP-1 activation induced by TNF-?. Sulforaphane inhibited TNF-?-induced ??? kinase activation, subsequent degradation of ???? and nuclear translocation of p65 NF-?B and decreased c-Jun and c-Fos protein level. This study suggests that sulforaphane inhibits the adhesive capacity of VSMC and downregulates the TNF-?-mediated induction of VCAM-1 in VSMC by inhibiting the MAPK, NF-?B and AP-1 signaling pathways and intracellular ROS production. Thus, sulforaphane may have beneficial effects to suppress inflammation within the atherosclerotic lesion.
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4-Chlorotetrazolo[1,5-a]quinoxaline inhibits activation of Syk kinase to suppress mast cells in vitro and mast cell-mediated passive cutaneous anaphylaxis in mice.
Toxicol. Appl. Pharmacol.
PUBLISHED: 06-29-2011
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4-Chlorotetrazolo[1,5-a]quinoxaline is a quinoxaline derivative. We aimed to study the effects of 4-chlorotetrazolo[1,5-a]quinoxaline on activation of mast cells in vitro and in mice. 4-Chlorotetrazolo[1,5-a]quinoxaline reversibly inhibited degranulation of mast cells in a dose-dependent manner, and also suppressed the expression and secretion of TNF-? and IL-4 in mast cells. Mechanistically, 4-chlorotetrazolo[1,5-a]quinoxaline inhibited activating phosphorylation of Syk and LAT, which are crucial for early Fc?RI-mediated signaling events, as well as Akt and MAP kinases, which play essential roles in the production of various pro-inflammatory cytokines in mast cells. Notably, although 4-chlorotetrazolo[1,5-a]quinoxaline inhibited the activation of Fyn and Syk, minimal inhibition was observed in mast cells in the case of Lyn. Furthermore, consistent with its in vitro activity, 4-chlorotetrazolo[1,5-a]quinoxaline significantly suppressed mast cell-mediated passive cutaneous anaphylaxis in mice. In summary, the results from this study demonstrate that 4-chlorotetrazolo[1,5-a]quinoxaline shows an inhibitory effect on mast cells in vitro and in vivo, and that this is mediated by inhibiting the activation of Syk in mast cells. Therefore, 4-chlorotetrazolo[1,5-a]quinoxaline could be useful in the treatment of mast cell-mediated allergic diseases.
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Complete genome sequence of the polycyclic aromatic hydrocarbon-degrading bacterium Alteromonas sp. strain SN2.
J. Bacteriol.
PUBLISHED: 06-24-2011
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Alteromonas sp. strain SN2, able to metabolize polycyclic aromatic hydrocarbons, was isolated from a crude oil-contaminated sea-tidal flat. Here we report the complete 4.97-Mb genome sequence and annotation of strain SN2. These will advance the understanding of strain SN2s adaptation to the sea-tidal flat ecosystem and its pollutant metabolic versatility.
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The optimal dose of esmolol and nicardipine for maintaining cardiovascular stability during rapid-sequence induction.
J Clin Anesth
PUBLISHED: 06-22-2011
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To determine the optimal dose of esmolol in combination with nicardipine in effectively blocking undesirable cardiovascular responses during rapid-sequence induction.
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MyD88-dependent Toll-like receptor signaling is required for murine macrophages response to IS2.
Int. Immunopharmacol.
PUBLISHED: 05-06-2011
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IS2, a soluble ?-glucan isolated from the cell wall of mutated Saccharomyces cerevisiae (S. cerevisiae) enhances the immune response compared to the wild type (WT) ?-glucan. In the present investigation we report that Toll-like receptor (TLR)/MyD88 signaling pathway was responsible in IS2 ?-glucan-mediated cellular response in RAW264.7 murine macrophages. Data revealed that IS2 ?-glucan significantly up-regulated the TLR2/TLR4 expression. Moreover, TLR2/TLR4 responds to IS2 resulting in murine macrophage activation. In addition, the IS2 signal led to cytokine secretions of IL-6 and TNF-?. In the case of thioglycolate-elicited peritoneal macrophages from MyD88-deficient mice, the decrease in cytokines was observed. Further the mitogen-activated protein kinases (MAPKs) phosphorylation was evident and degradation of I?B-? was increased after stimulation with IS2 ?-glucan. Further examination with MyD88-deficient mice revealed that the MyD88 pathway might play an important role for IS2 ?-glucan-mediated activation of macrophages.
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Video-assisted thoracoscopic surgery plus lumbar mini-open surgery for adolescent idiopathic scoliosis.
Yonsei Med. J.
PUBLISHED: 05-04-2011
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The objectives of this study are to describe the outcome of adolescent idiopathic scoliosis (AIS) patients treated with Video Assisted Thoracoscopic Surgery (VATS) plus supplementary minimal incision in the lumbar region for thoracic and lumbar deformity correction and fusion.
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Expressed sequence tag analysis of the erythrocytic stage of Plasmodium berghei.
Korean J. Parasitol.
PUBLISHED: 04-16-2011
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Rodent malaria parasites, such as Plasmodium berghei, are practical and useful model organisms for human malaria research because of their analogies to the human malaria in terms of structure, physiology, and life cycle. Exploiting the available genetic sequence information, we constructed a cDNA library from the erythrocytic stages of P. berghei and analyzed the expressed sequence tag (EST). A total of 10,040 ESTs were generated and assembled into 2,462 clusters. These EST clusters were compared against public protein databases and 48 putative new transcripts, most of which were hypothetical proteins with unknown function, were identified. Genes encoding ribosomal or membrane proteins and purine nucleotide phosphorylases were highly abundant clusters in P. berghei. Protein domain analyses and the Gene Ontology functional categorization revealed translation/protein folding, metabolism, protein degradation, and multiple family of variant antigens to be mainly prevalent. The presently-collected ESTs and its bioinformatic analysis will be useful resources to identify for drug target and vaccine candidates and validate gene predictions of P. berghei.
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Plasmon response of a quantum-confined electron gas probed by core-level photoemission.
Phys. Rev. Lett.
PUBLISHED: 03-21-2011
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We demonstrate the existence of quantized "bulk" plasmons in ultrathin magnesium films on Si(111) by analyzing plasmon-loss satellites in core-level photoemission spectra, recorded as a function of the film thickness d. Remarkably, the plasmon energy is shown to vary as 1/d2 all the way down to three atomic layers. The loss spectra are dominated by the n=1 and n=2 normal modes, consistent with the excitation of plasmons involving quantized electronic subbands. With decreasing film thickness, spectral weight is gradually transferred from the plasmon modes to the low-energy single-particle excitations. These results represent striking manifestations of the role of quantum confinement on plasmon resonances in precisely controlled nanostructures.
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KR33426, [2-(2,5-dichlorophenyl)-5-methyloxazol-4yl]carbonylguanidine, is a novel compound to be effective on mouse systemic lupus erythematosus.
Eur. J. Pharmacol.
PUBLISHED: 03-14-2011
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B cell-activating factor (BAFF) is a key regulator of B lymphocyte development. Signals from BAFF are transmitted through binding to a specific BAFF receptor (BAFF-R). Here, we established screening method to find a specific inhibitor for the interference of BAFF-BAFF-R interactions. We screened oxazole-4-carbonylguanidine derivatives and selected KR33426, [2-(2,5-dichlorophenyl)-5-methyloxazol-4yl]carbonylguanidine, as a candidate to interfere BAFF-BAFF-R interactions. KR33426 inhibited BAFF-mediated anti-apoptotic effect on splenocytes as judged by hypodiploid cell formation. KR33426 also increased the degradation of procaspase-3 that was inhibited by BAFF protein. In addition, we examined whether KR33426 was effective on the treatment of systemic lupus erythematosus-like symptom in MRL(lpr/lpr) mouse. When 5 or 10mg/kg KR33426 was intraperitoneally administered to MRL(lpr/lpr) mice for 4 weeks, histopathological changes were ameliorated in the narrowed space between renal glomerulus and glomerulus capsule. KR33426 reduced B220(+) B cell population and B cell mitogen, lipopolysaccharide-stimulated lymphocyte proliferation in splenocytes. KR33426 attenuated an increase in CD43(-)IgM(+) immature pro-B and a decrease in CD21(+) IgM(+) T2-B and IgD(+) IgM(-)recirculating-B cells on B cell development. Data show that KR33426 inhibits BAFF-BAFF-R interactions and it is effective on the treatment of systemic lupus erythematosus-like symptom in MRL(lpr/lpr) mice. Thus, it suggests that KR33426 is a novel candidate to develop anti-autoimmune therapeutics by the interference of BAFF-BAFF-R interactions, specifically.
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Toll-like receptor 4-mediated cAMP production up-regulates B-cell activating factor expression in Raw264.7 macrophages.
Exp. Cell Res.
PUBLISHED: 03-14-2011
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B-cell activating factor (BAFF) plays a role in the generation and the maintenance of mature B cells. Lipopolysaccharide (LPS) increased BAFF expression through the activation of toll-like receptor 4 (TLR4)-dependent signal transduction. Here, we investigated the mechanism of action on mouse BAFF (mBAFF) expression by cAMP production in Raw264.7 mouse macrophages. mBAFF expression was increased by the treatment with a cAMP analogue, dibutyryl-cAMP which is the activator of protein kinase A (PKA), cAMP effector protein. PKA activation was measured by the phosphorylation of cAMP-response element binding protein (CREB) on serine 133 (S133). cAMP production and CREB (S133) phosphorylation were augmented by LPS-stimulation. While mBAFF promoter activity was enhanced by the co-transfection with pS6-RSV-CREB, it was reduced by siRNA-CREB. PKA inhibitor, H-89, reduced CREB (S133) phosphorylation and mBAFF expression in control and LPS-stimulated macrophages. Another principal cAMP effector protein is cAMP-responsive guanine nucleotide exchange factor (Epac), a Rap GDP exchange factor. Epac was activated by the treatment with 8-(4-chloro-phenylthio)-2-O-methyladenosine-3,5-cyclic monophosphate (CPT), Epac activator, as judged by the measurement of Rap1 activation. Basal level of mBAFF expression was increased by CPT treatment. LPS-stimulated mBAFF expression was also slightly enhanced by co-treatment with CPT. In addition, dibutyryl-cAMP and CPT enhanced mBAFF expression in bone marrow-derived macrophages (BMDM). With these data, it suggests that the activation of PKA and cAMP/Epac1/Rap1 pathways could be required for basal mBAFF expression, as well as being up-regulated in the TLR4-induced mBAFF expression.
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The effect of preparation order on the crystal structure of yttria-stabilized tetragonal zirconia polycrystal and the shear bond strength of dental resin cements.
Dent Mater
PUBLISHED: 03-11-2011
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The purpose of this study was to evaluate the effect of preparation order on the crystal structure of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) and the shear bond strength of dental resin cements.
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Vascular tube formation and angiogenesis induced by polyvinylpyrrolidone-coated silver nanoparticles.
Toxicol. Lett.
PUBLISHED: 03-04-2011
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Silver nanoparticles (AgNPs) are one of the most commonly used nanomaterials due to their antibacterial properties. In this study, we examined the effects of polyvinylpyrrolidone (PVP)-coated AgNPs (average size 2.3nm) on angiogenesis in both an in vivo model and an in vitro endothelial cell line, SVEC4-10. Increased angiogenesis was detected around the injection site of AgNP-containing Matrigel in vivo. AgNPs also increased the infiltration of endothelial cells and the hemoglobin (Hb) content in AgNP-Matrigel plugs implanted into mice. AgNPs induced endothelial cell tube formation on growth factor-reduced Matrigel, production of reactive oxygen species (ROS), and production of angiogenic factors, such as vascular endothelial growth factor (VEGF) and nitric oxide (NO), in SVEC4-10 cells. In addition, AgNPs promoted the activation of FAK, Akt, ERK1/2, and p38, which are all involved in VEGF receptor (VEGFR)-mediated signaling. Finally, AgNP-treated tumors caused angiogenesis around tumors in B16F10 melanomas after they were injected into mice, and the Hb concentration in the tumors increased in a concentration-dependent manner with AgNP treatment. Thus, our study suggests that exposure to AgNPs can cause angiogenesis through the production of angiogenic factors.
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High abundance and role of antifungal bacteria in compost-treated soils in a wildfire area.
Microb. Ecol.
PUBLISHED: 02-23-2011
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Compost has been widely used in order to promote vegetation growth in post-harvested and burned soils. The effects on soil microorganisms were scarcely known, so we performed the microbial analyses in a wildfire area of the Taebaek Mountains, Korea, during field surveys from May to September 2007. Using culture-dependent and -independent methods, we found that compost used in burned soils influenced a greater impact on soil fungi than bacteria. Compost-treated soils contained higher levels of antifungal strains in the genera Bacillus and Burkholderia than non-treated soils. When the antifungal activity of Burkholderia sp. strain O1a_RA002, which had been isolated from a compost-treated soil, was tested for the growth inhibition of bacteria and fungi isolated from burned soils, the membrane-filtered culture supernatant inhibited 19/37 fungal strains including soil fungi, Eupenicillium spp. and Devriesia americana; plant pathogens, Polyschema larviformis and Massaria platani; an animal pathogen, Mortierella verticillata; and an unidentified Ascomycota. However, this organism only inhibited 11/151 bacterial strains tested. These patterns were compatible with the culture-independent DGGE results, suggesting that the compost used in burned soils had a greater impact on soil fungi than bacteria through the promotion of the growth of antifungal bacteria. Our findings indicate that compost used in burned soils is effective in restoring soil conditions to a state closer to those of nearby unburned forest soils at the early stage of secondary succession.
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A spinal cord astrocytoma and its concurrent osteoblastic metastases at the time of the initial diagnosis: a case report and literature review.
Korean J Radiol
PUBLISHED: 02-22-2011
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Bone metastasis from a spinal cord astrocytoma has been reported only twice in the English medical literature. It is generally known that bone metastasis is found after the initial diagnosis with/without intervening surgery rather than being found at the time of the diagnosis of astrocytoma. The purpose of this article is to report for the first time a case of concurrent bone metastasis from a spinal cord astrocytoma at the time of diagnosing the spinal cord astrocytoma.
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Src activates HIF-1? not through direct phosphorylation of HIF-1? specific prolyl-4 hydroxylase 2 but through activation of the NADPH oxidase/Rac pathway.
Carcinogenesis
PUBLISHED: 02-18-2011
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Hypoxia-Inducible Factor (HIF)-1?/? heterodimer is a master transcription factor for several genes involved in angiogenesis, glycolysis, pH balance and metastasis. These HIF-1 target genes help tumors to overcome forthcoming metabolic obstacles as they grow. Under normoxic condition, the HIF-1? subunit is hydroxylated by its specific prolyl-4 hydroxylase 2, given the acronym PHD2. Hydroxylated HIF-1? becomes a target for von Hippel-Lindau (VHL), which functions as an E3 ubiquitin ligase. Src prevents hydroxylation-dependent ubiquitinylation of HIF-1?, thus stabilizing it under normoxic conditions. We found that active Src does not directly phosphorylate any tyrosine residue of PHD2. In vitro hydroxylation reaction showed that the presence of the purified active Src protein does not inhibit the hydroxylation activity of the purified PHD2 enzymes. Instead of directly inhibiting PHD2, Src recruits several downstream-signaling pathways to intercept hydroxylation-dependent ubiquitinylation of HIF-1?. Using biochemical and genetic inhibition, we demonstrated that Src requires reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase/Rac complex for stabilization of HIF-1?. We found that excess vitamin C treatment attenuates Src-induced HIF-1? activation. HIF-1?-hydroxylation-dependent VHL pull-down assay showed that Src inhibits cellular PHD2 activity by inducing ROS production in a mechanism involving Rac1-dependent NADPH oxidase. Src-induced ROS reduces cellular vitamin C, which is required for the activity of PHD2, thus Src can block VHL recruitment of HIF-1?, leading to stabilization of HIF-1?.
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Atg3-mediated lipidation of Atg8 is involved in encystation of Acanthamoeba.
Korean J. Parasitol.
PUBLISHED: 02-07-2011
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Autophagy is a catabolic process involved in the degradation of a cells own components for cell growth, development, homeostasis, and the recycling of cellular products. Autophagosome is an essential component in the protozoan parasite during differentiation and encystation. The present study identified and characterized autophagy-related protein (Atg) 3, a member of Atg8 conjugation system, in Acanthamoeba castellanii (AcAtg3). AcAtg3 encoding a 304 amino acid protein showed high similarity with the catalytic cysteine site of other E2 like enzymes of ubiquitin system. Predicted 3D structure of AcAtg3 revealed a hammer-like shape, which is the characteristic structure of E2-like enzymes. The expression level of AcAtg3 did not increase during encystation. However, the formation of mature cysts was significantly reduced in Atg3-siRNA transfected cells in which the production of Atg8-phosphatidylethanolamine conjugate was inhibited. Fluorescent microscopic analysis revealed that dispersed AcAtg3-EGFP fusion protein gathered around autophagosomal membranes during encystation. These results provide important information for understanding autophagic machinery through the lipidation reaction mediated by Atg3 in Acanthamoeba.
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The effects of preoperative intravenous acetaminophen in patients undergoing abdominal hysterectomy.
Arch. Gynecol. Obstet.
PUBLISHED: 02-04-2011
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Although intravenous acetaminophen is commonly used for the management of postoperative pain, very limited evidence supports the usefulness of preoperative administration. The aim of this study was to determine the analgesic effect of preoperative acetaminophen on opioid consumption, pain scores, and side effects in patients receiving an elective abdominal hysterectomy.
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An increase in mouse tumor growth by an in vivo immunomodulating effect of titanium dioxide nanoparticles.
J Immunotoxicol
PUBLISHED: 02-03-2011
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Here, we investigated whether titanium dioxide (TiO?) nanoparticles affect in vivo tumor growth through the modulation of mononuclear leukocytes. In vitro lymphocyte proliferation by lipopolysaccharide (LPS) or concanavalin A (ConA) was reduced by < 25 nm TiO? with a dose-dependent manner. Similarly, TiO? nanoparticles inhibited nitric oxide (NO) production from bone marrow-derived macrophages obtained from naïve mice. When mice were intraperitoneally (IP) injected with < 25 or < 100 nm TiO? once a day for 7 days, total cell number of splenocytes was reduced in the spleen of TiO? nanoparticle-exposed mice. Both CD4+ and CD8+ T-lymphocyte numbers were significantly decreased and B-lymphocyte development was retarded by host exposure to the TiO? nanoparticles. LPS-stimulated spleen cell proliferation was significantly reduced by host exposure to < 25 or < 100 nm TiO?, but no changes were detected in ConA-stimulated spleen cell proliferation. Further, LPS-stimulated cytokine production by peritoneal macrophages and the percentage of NK1.1+ natural killer cells among splenocytes was reduced by the host exposures to the TiO? nanoparticles. When mice were IP injected with TiO? nanoparticles once a day for 28 days prior to the subcutaneous implantation of B16F10 melanoma cells, tumor growth was subsequently significantly increased. Collectively, these results show that TiO? nanoparticles may damage the development and proliferation of B- and T-lymphocytes, reduce the activity of macrophages, and decrease natural killer (NK) cell population levels, outcomes that appear to lead to an increase in tumor growth in situ. These studies allow us to suggest that TiO? nanoparticles might have the potential to enhance tumor growth through immunomodulation of B- and T-lymphocytes, macrophages, and NK cells.
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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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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.