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Find video protocols related to scientific articles indexed in Pubmed.
Intermittent Antibiotic Therapy for Nodular Bronchiectatic Mycobacterium avium Complex Lung Disease.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 11-14-2014
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Rationale: Although intermittent, three-times-weekly therapy is recommended for the initial treatment of non-cavitary nodular bronchiectatic Mycobacterium avium complex (MAC) lung disease, supporting data are limited. Objectives: To evaluate the clinical efficacy of intermittent therapy compared with daily therapy for nodular bronchiectatic MAC lung disease. Methods: A retrospective cohort study of 217 patients with treatment-naïve non-cavitary nodular bronchiectatic MAC lung disease. All patients received either daily (n = 99) or intermittent therapy (n = 118) that included clarithromycin or azithromycin, rifampin, and ethambutol. Measurements and Results: Modification of the initial antibiotic therapy occurred more frequently in the daily therapy group than in the intermittent therapy group (46% vs. 21%, P < 0.001); in particular, ethambutol was more frequently discontinued in the daily therapy group than in the intermittent therapy group (24% vs. 1%, P < 0.001). However, the rates of symptomatic improvement, radiographic improvement, and sputum culture conversion were not different between the two groups (daily therapy vs. intermittent therapy; 75% vs. 82%, P = 0.181; 68% vs. 73%, P = 0.402; 76% vs. 67%, P = 0.154; respectively). In addition, the adjusted proportion of sputum culture conversion was similar between the daily therapy (71.3%, 95% confidence interval [CI] 59.1-81.1%) and the intermittent therapy groups (73.6%, 95% CI 62.9-82.2%, P = 0.785). Conclusions: These results suggest that intermittent three-times-weekly therapy with a macrolide, rifampin, and ethambutol is a reasonable initial treatment regimen for patients with non-cavitary nodular bronchiectatic MAC lung disease. Clinical trial registration can be found at www. clinicaltrials.gov, ID NCT00970801.
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Significant Association of oncogene YAP1 with Poor Prognosis and Cetuximab Resistance in Colorectal Cancer Patients.
Clin. Cancer Res.
PUBLISHED: 11-13-2014
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Purpose: Activation of YAP1, novel oncogene in Hippo pathway, has been observed in many cancers including colorectal cancer (CRC). We investigated if activation of YAP1 is significantly associated with prognosis or treatment outcomes in CRC Experimental Design: A gene expression signature reflecting YAP1 activation was identified in CRC cells, and CRC patients were stratified into two groups according to this signature: activated YAP1 CRC (AYCC) or inactivated YAP1 CRC (IYCC). Stratified patients in five test cohorts were evaluated to determine the effect of the signature on CRC prognosis and response to cetuximab treatment. Results: The activated YAP1 signature was associated with poor prognosis for CRC in four independent patient cohorts with stage I-III disease (total n = 1,028). In a multivariate analysis, the impact of the YAP1 signature on the disease-free survival was independent of other clinical variables [hazard ratio (HR), 1.63; 95% confidence interval (CI), 1.25-2.13; P < 0.001]. In patients with stage IV CRC and wild-type KRAS, IYCC patients had a better disease control rate and progression-free survival (PFS) after cetuximab monotherapy than did AYCC patients; however, in patients with KRAS mutations, PFS duration after cetuximab monotherapy was not different between IYCC and AYCC patients. In multivariate analysis, the effect of YAP1 activation on PFS was independent of KRAS mutation status and other clinical variables (HR, 1.82; 95% CI, 1.05-3.16; P = 0.03). Conclusions: Activation of YAP1 is highly associated with poor prognosis for CRC and may be useful in identifying patients with metastatic CRC resistant to cetuximab.
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High performance CNT point emitter with graphene interfacial layer.
Nanotechnology
PUBLISHED: 10-20-2014
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Carbon nanotubes (CNTs) have great potential in the development of high-power electron beam sources. However, for such a high-performance electronic device, the electric and thermal contact problem between the metal and CNTs must be improved. Here, we report graphene as an interfacial layer between the metal and CNTs to improve the interfacial contact. The interfacial graphene layer results in a dramatic decrease of the electrical contact resistance by an order of 2 and an increase of the interfacial thermal conductivity by 16%. Such a high improvement in the electrical and thermal interface leads to superior field emission performance with a very low turn-on field of 1.49 V ?m(-1) at 10 ?A cm(-2) and a threshold field of 2.00 V ?m(-1) at 10 mA cm(-2), as well as the maximum current of 16 mA (current density of 2300 A cm(-2)).
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Effect of Rifampin and Rifabutin on Serum Itraconazole Levels in Patients with Chronic Pulmonary Aspergillosis and Coexisting Nontuberculous Mycobacterial Infection.
Antimicrob. Agents Chemother.
PUBLISHED: 10-15-2014
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The effects of rifampin and rifabutin on serum itraconazole levels in patients with chronic pulmonary aspergillosis were investigated. Serum itraconazole concentrations were significantly lower in patients who received itraconazole with rifampin (median, 0.1 ?g/mL; P < 0.001) or rifabutin (median, 0.34 ?g/mL, P < 0.001) compared with those receiving itraconazole alone (median 5.92 ?g/mL). Concomitant use of rifampin or rifabutin and itraconazole should be avoided in patients with chronic pulmonary aspergillosis and coexisting mycobacterial infections.
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Effect of Graphitic Layers Encapsulating Single-Crystal Apatite Nanowire on the Osteogenesis of Human Mesenchymal Stem Cells.
J Phys Chem B
PUBLISHED: 10-11-2014
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An ideally designed scaffold for tissue engineering must be able to provide an environment that recapitulates the physiological conditions to control stem cell function. Here, we compared vertically aligned single-crystal apatite nanowires sheathed in graphitic layers (SANGs) with single-crystal apatite nanowires (SANs), which had the same geometric properties as-but differing nanotopographic surface chemistry than-SANGs, in order to evaluate the effect of the graphitic layer on the behavior of human mesenchymal stem cells (hMSCs). The difference in nanotopographic surface chemistry did not affect hMSC adhesion, growth, or morphology. However, hMSCs were more effectively differentiated into bone cells on SANGs through interaction with graphitic layers, which later degraded and thereby allowed the cells to continue differentiation on the bare apatite nanowires. Thus, SANGs provide an excellent microenvironment for the osteogenic differentiation of hMCS.
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Spontaneous Pneumomediastinum, Pneumopericardium, and Pneumothorax with Respiratory Failure in a Patient with AIDS and Pneumocystis jirovecii Pneumonia.
Infect Chemother
PUBLISHED: 09-24-2014
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Spontaneous pneumothorax occurs in up to 35% of patients with Pneumocystis jirovecii pneumonia. However, spontaneous pneumomediastinum and pneumopericardium are uncommon complications in patients infected with human immunodeficiency virus, with no reported incidence rates, even among patients with acquired immunodeficiency syndrome (AIDS) and P. jirovecii pneumonia. We report a case of spontaneous pneumomediastinum, pneumopericardium, and pneumothorax with respiratory failure during treatment of P. jirovecii pneumonia in a patient with AIDS; the P. jirovecii infection was confirmed by performing methenamine silver staining of bronchoalveolar lavage specimens. This case suggests that spontaneous pneumomediastinum and pneumopericardium should be considered in patients with AIDS and P. jirovecii pneumonia.
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Interleukin-32? downregulates the activity of the B-cell CLL/lymphoma 6 protein by inhibiting protein kinase C?-dependent SUMO-2 modification.
Oncotarget
PUBLISHED: 09-24-2014
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A proinflammatory cytokine IL-32 acts as an intracellular mediator. IL-32? interacts with many intracellular molecules, but there are no reports of interaction with a transcriptional repressor BCL6. In this study, we showed that PMA induces an interaction between IL-32?, PKC?, and BCL6, forming a trimer. To identify the mechanism of the interaction, we treated cells with various inhibitors. In HEK293 and THP-1 cell lines, treatment with a pan-PKC inhibitor, PKC? inhibitor, and PKC? inhibitor decreased BCL6 and IL-32? protein expression. MAPK inhibitors and classical PKC inhibitor did not decrease PMA-induced BCL6 and IL-32? protein expression. Further, the pan-PKC inhibitor and PKC? inhibitor disrupted PMA-induced interaction between IL-32? and BCL6. These data demonstrate that the intracellular interaction between IL-32? and BCL6 is induced by PMA-activated PKC?. PMA induces post-translational modification of BCL6 by conjugation to SUMO-2, while IL-32? inhibits. PKC? inhibition eliminated PMA-induced SUMOylation of BCL6. Inhibition of BCL6 SUMOylation by IL-32? affected the cellular function and activity of the transcriptional repressor BCL6 in THP-1 cells. Thus, we showed that IL-32? is a negative regulator of the transcriptional repressor BCL6. IL-32? inhibits BCL6 SUMOylation by activating PKC?, resulting in the modulation of BCL6 target genes and cellular functions of BCL6.
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Transcriptional regulation of fksA, a ?-1,3-glucan synthase gene, by the APSES protein StuA during Aspergillus nidulans development.
J. Microbiol.
PUBLISHED: 09-17-2014
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The temporal and spatial regulation of ?-1,3-glucan synthesis plays an important role in morphogenesis during fungal growth and development. Northern blot analysis showed that the transcription of fksA, the gene encoding ?-1,3-glucan synthase in Aspergillus nidulans, was cell-cycle-dependent and increased steadily over the duration of the vegetative period, but its overall expression during the asexual and sexual stages was fairly constant up until the time of transcription cessation. In an A. nidulans strain mutated in the eukaryotic bHLH-like APSES transcription factor stuA1, the transcriptional level of fksA, and consequently the content of alkali-insoluble cell wall ?-glucan, significantly increased at the conidial chain formation and maturation stage. Electrophoretic mobility shift assays revealed that StuA was bound to StREs (StuA Response Elements) on the fksA promoter region. Promoter analysis with sGFP-fusion constructs also indicated the negative regulation of fksA expression by StuA, especially during asexual development. Taken together, these data suggest that StuA plays an important role in cell wall biogenesis during the development of A. nidulans, by controlling the transcription level of fksA.
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In silico analysis of genomic data for construction of nuclear receptor network.
Methods Mol. Biol.
PUBLISHED: 09-04-2014
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Availability of genome-wide information in public database provides unprecedented opportunity for developing new strategy to uncover potential interactions of members in large functional family. Here we describe a systematic strategy for constructing and analyzing potential interaction map to uncover novel interaction between nuclear receptors that may play important roles in human disease. This in silico approach can prioritize candidate interactions for further functional validation and assess its clinical relevance.
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Interleukin-32? modulates promyelocytic leukemia zinc finger gene activity by inhibiting protein kinase C?-dependent sumoylation.
Int. J. Biochem. Cell Biol.
PUBLISHED: 08-29-2014
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Interleukin-32 (IL-32) is a proinflammatory cytokine. However, there is growing evidence that IL-32 also plays a mediatory role intracellularly. In this study, we present evidence that IL-32? modifies and inhibits promyelocytic leukemia zinc finger (PLZF), a sequence-specific transcriptional regulator that regulates the expression of a subset of interferon (IFN)-stimulated genes (ISGs). We screened IL-32?-interacting proteins in a human spleen cDNA library using the yeast two-hybrid assay, and investigated the functional relevance of the interaction between IL-32? and PLZF. We demonstrated that IL-32? interacts with protein kinase C (PKC)? and PKC? in a phorbol 12-myristate 13-acetate (PMA) dependent way, and that PKC? regulates the interaction of IL-32? with PLZF. We verified the involvement of PKC? in the interaction between these proteins by using various PKC inhibitors. PLZF is known to be modified by small ubiquitin-like modifier (SUMO)-1, but it is unclear whether SUMO-2 conjugation of PLZF occurs. We showed that IL-32? inhibited SUMO-2-conjugation of PLZF. Further, we demonstrated that sumoylated PLZF decreased when IL-32? was co-expressed. PKC? affected the sumoylation of PLZF only in the presence of IL-32? because PKC inhibitor treatment did not reduce PLZF sumoylation in the absence of IL-32?. We finally investigated whether IL-32?-mediated inhibition of PLZF sumoylation affected the transcriptional activity of PLZF, and demonstrated that the inhibition of sumoylation of PLZF by IL-32? down-regulated ISGs induced by PLZF. Together, our data suggest that IL-32? associates with PLZF and PKC?, and then inhibits PLZF sumoylation, resulting in suppression of the transcriptional activity of PLZF.
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A study of docetaxel and irinotecan in children and young adults with recurrent or refractory Ewing sarcoma family of tumors.
BMC Cancer
PUBLISHED: 08-28-2014
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Patients with Ewing sarcoma family of tumors (ESFT) who are resistant even to salvage chemotherapy, have dismal prognoses and few therapeutic options. Because the docetaxel/irinotecan (DI) combination has not been previously evaluated in ESFT, we prospectively evaluated its use in patients with recurrent or refractory ESFT.
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Hypoxia-modulated gene expression profiling in sea urchin (Strongylocentrotus nudus) immune cells.
Ecotoxicol. Environ. Saf.
PUBLISHED: 08-24-2014
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Hypoxia is an issue that affects ocean coastal waters worldwide. It has severe consequences for marine organisms, including death and rapid adaptive changes in metabolic organization. Although some aquatic animals are routinely exposed and resistant to severe environmental hypoxia, others such as sea urchins (Strongylocentrotus nudus) have a limited capacity to withstand this stress. In this study, hypoxia induced a significant increase in the number of red spherule cells among coelomocytes, which function as immune cells. This suggests that sea urchin immune cells could be used as a biological indicator of hypoxic stress. In the current study, we used cDNA microarrays to investigate the differential expression patterns of hypoxia-regulated genes to better understand the molecular mechanisms underlying the response of immune cells to hypoxia. Surprisingly, the predominant major effect of hypoxia was the widespread suppression of gene expression. In particular, the expression of RNA helicase and GATA-4/5/6 was decreased significantly in response to hypoxia, even in field conditions, suggesting that they could be utilized as sensitive bioindicators of hypoxic stress in the sea urchin.
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Comparison of strain and shear wave elastography for the differentiation of benign from malignant breast lesions, combined with B-mode ultrasonography: qualitative and quantitative assessments.
Ultrasound Med Biol
PUBLISHED: 08-15-2014
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Our aim was to compare the diagnostic performance of strain elastography (SE) and shear-wave elastography (SWE), combined with B-mode ultrasonography (US), in breast cancer. For 79 breast lesions that underwent SE and SWE, two radiologists reviewed five data sets (B-mode US, SWE, SE and two combined sets). Qualitative and quantitative elastographic data and Breast Imaging Reporting and Data System (BI-RADS) categories were recorded. The area under the receiver operating characteristic curve (AUC) was evaluated. No significant difference in the AUC between the two elastography methods was noted. After subjective assessment by reviewers, the AUC for the combined sets was improved (SWE, 0.987; SE, 0.982; B-mode US, 0.970; p < 0.05). When SE and SWE were added, 38% and 56% of benign BI-RADS category 4a lesions with a low suspicion of cancer were downgraded without false-negative results, respectively. SE and SWE performed similarly. Therefore, addition of SE or SWE improved the diagnostic performance of B-mode US, potentially reducing unnecessary biopsies.
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Evaluation of the Accuracy of the EasyTest™ Malaria Pf/Pan Ag, a Rapid Diagnostic Test, in Uganda.
Korean J. Parasitol.
PUBLISHED: 07-10-2014
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In recent years, rapid diagnostic tests (RDTs) have been widely used for malaria detection, primarily because of their simple operation, fast results, and straightforward interpretation. The Asan EasyTest™ Malaria Pf/Pan Ag is one of the most commonly used malaria RDTs in several countries, including Korea and India. In this study, we tested the diagnostic performance of this RDT in Uganda to evaluate its usefulness for field diagnosis of malaria in this country. Microscopic and PCR analyses, and the Asan EasyTest™ Malaria Pf/Pan Ag rapid diagnostic test, were performed on blood samples from 185 individuals with suspected malaria in several villages in Uganda. Compared to the microscopic analysis, the sensitivity of the RDT to detect malaria infection was 95.8% and 83.3% for Plasmodium falciparum and non-P. falciparum, respectively. Although the diagnostic sensitivity of the RDT decreased when parasitemia was ?500 parasites/µl, it showed 96.8% sensitivity (98.4% for P. falciparum and 93.8% for non-P. falciparum) in blood samples with parasitemia ?100 parasites/µl. The specificity of the RDT was 97.3% for P. falciparum and 97.3% for non-P. falciparum. These results collectively suggest that the accuracy of the Asan EasyTest™ Malaria Pf/Pan Ag makes it an effective point-of-care diagnostic tool for malaria in Uganda.
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sAPP modulates iron efflux from brain microvascular endothelial cells by stabilizing the ferrous iron exporter ferroportin.
EMBO Rep.
PUBLISHED: 05-27-2014
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A sequence within the E2 domain of soluble amyloid precursor protein (sAPP) stimulates iron efflux. This activity has been attributed to a ferroxidase activity suggested for this motif. We demonstrate that the stimulation of efflux supported by this peptide and by sAPP? is due to their stabilization of the ferrous iron exporter, ferroportin (Fpn), in the plasma membrane of human brain microvascular endothelial cells (hBMVEC). The peptide does not bind ferric iron explaining why it does not and thermodynamically cannot promote ferrous iron autoxidation. This peptide specifically pulls Fpn down from the plasma membrane of hBMVEC; based on these results, FTP, for ferroportin-targeting peptide, correctly identifies the function of this peptide. The data suggest that in stabilizing Fpn via the targeting due to the FTP sequence, sAPP will increase the flux of iron into the cerebral interstitium. This inference correlates with the observation of significant iron deposition in the amyloid plaques characteristic of Alzheimer's disease.
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IL-32? downregulates CCL5 expression through its interaction with PKC? and STAT3.
Cell. Signal.
PUBLISHED: 05-21-2014
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Interleukin-32 (IL-32) exists in several isoforms and plays an important role in inflammatory response. Recently, we identified a new isoform, IL-32?, and performed a microarray analysis to identify IL-32?-regulated genes in THP-1 myelomonocytic cells. Upon stimulating IL-32?-expressing THP-1 cells with phorbol myristate acetate (PMA), we found that the CCL5 transcript level was significantly reduced. We confirmed the downregulation of CCL5 protein expression by using an enzyme-linked immunosorbent assay (ELISA). Because STAT3 phosphorylation on Ser727 by PKC? is reported to suppress CCL5 protein expression, we examined whether IL-32?-mediated STAT3 Ser727 phosphorylation occurs through an interaction with PKC?. In this study, we first demonstrate that IL-32? interacts with PKC? and STAT3 using co-immunoprecipitation (Co-IP) and pulldown assay. Moreover, STAT3 was rarely phosphorylated on Ser727 in the absence of IL-32?, leading to the binding of STAT3 to the CCL5 promoter. These results indicate that IL-32?, through its interaction with PKC?, downregulates CCL5 expression by mediating the phosphorylation of STAT3 on Ser727 to render it transcriptionally inactive. Therefore, similar to what we have reported for IL-32? and IL-32?, our data from this study suggests that the newly identified IL-32? isoform also acts as an intracellular modulator of inflammation.
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Role of interventional radiology in trauma care: retrospective study from single trauma center experience.
Am J Emerg Med
PUBLISHED: 05-10-2014
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Although interventional management is now regarded as essential in trauma care, the effect on clinical result remains uncertain. We conducted this retrospective study to figure out the role of interventional management in trauma care.
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Phylogenetic relationships of 3 Korean Neodiplostomum species (Digenea: Neodiplostomidae) based on partial CO1 gene.
Korean J. Parasitol.
PUBLISHED: 04-26-2014
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The phylogenetic relationships of the 3 Neodiplostomum spp. (Digenea: Neodiplostomidae) occurring in Korea (N. seoulense, N. leei, and N. boryongense) were analyzed using the partial mitochondrial cytochrome c oxidase subunit 1 (CO1) gene. The adult flukes were recovered from Sprague-Dawley rats (N. seoulense) and newborn chicks (N. leei and N. boryongense) experimentally infected with the neodiplostomula from the grass snake, Rhabdophis tigrinus tigrinus. The genomic DNA was amplified using specific primers, and the sequence of CO1 was obtained. According to the results, the pairwise similarity was 96.1% between N. boryongense and N. seoulense, but was 95.0% between N. boryongense and N. leei and 94.2% between N. leei and N. seoulense. The results demonstrated a closer phylogenetic relationship between N. seoulense and N. boryongense. This high relationship of N. seoulense and N. boryongense may be related to their similar morphologic features including the limited distribution of vitellaria and the presence of a genital cone. N. leei is distinct on the other hand with an extensive distribution of vitellaria and the absence of a genital cone.
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Risk factors for acquiring potentially drug-resistant pathogens in immunocompetent patients with pneumonia developed out of hospital.
Respiration
PUBLISHED: 04-01-2014
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The concept of healthcare-associated pneumonia (HCAP) exists to identify patients infected with highly resistant pathogens who are exposed to the healthcare environment. However, many studies have included immunosuppressed patients who were excluded from the original concept.
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Ultrasmooth, extremely deformable and shape recoverable Ag nanowire embedded transparent electrode.
Sci Rep
PUBLISHED: 03-17-2014
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Transparent electrodes have been widely used in electronic devices such as solar cells, displays, and touch screens. Highly flexible transparent electrodes are especially desired for the development of next generation flexible electronic devices. Although indium tin oxide (ITO) is the most commonly used material for the fabrication of transparent electrodes, its brittleness and growing cost limit its utility for flexible electronic devices. Therefore, the need for new transparent conductive materials with superior mechanical properties is clear and urgent. Ag nanowire (AgNW) has been attracting increasing attention because of its effective combination of electrical and optical properties. However, it still suffers from several drawbacks, including large surface roughness, instability against oxidation and moisture, and poor adhesion to substrates. These issues need to be addressed before wide spread use of metallic NW as transparent electrodes can be realized. In this study, we demonstrated the fabrication of a flexible transparent electrode with superior mechanical, electrical and optical properties by embedding a AgNW film into a transparent polymer matrix. This technique can produce electrodes with an ultrasmooth and extremely deformable transparent electrode that have sheet resistance and transmittance comparable to those of an ITO electrode.
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Comparative analysis of flavonoids and polar metabolite profiling of Tanno-original and Tanno-high rutin buckwheat.
J. Agric. Food Chem.
PUBLISHED: 03-17-2014
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Rutin is an important indicator for evaluating the quality of buckwheat. In this study, flavonoid biosynthesis was compared between two common cultivars (an original and a high-rutin line) of buckwheat, Fagopyrum esculentum Moench. Transcriptional levels of the main flavonoid biosynthetic genes were analyzed by real-time PCR, and main flavonoid metabolites were detected by high-performance liquid chromatography (HPLC); levels of gene expression varied among organs of the two cultivars. Significantly higher transcription levels of most flavonoid biosynthetic genes, except FeFLS1, were detected in stems of the high-rutin line than in stems of the original line. FeCHI and FeFLS2 genes also showed higher expression levels in seeds of the high-rutin cultivar. In contrast, FePAL, FeC4H, Fe4CL1, FeCHS, FeF3H, FeF3'H, FeFLS2, and FeDFR were highly detected in the roots of the original line. The HPLC results indicated 1.73-, 1.62-, and 1.77-fold higher accumulation of rutin (the primary flavonoid compound) in leaves, stems, and mature seeds of the high-rutin cultivar (24.86, 1.46, and 1.36 ?g/mg, respectively) compared with the original cultivar (14.40, 0.90, and 0.77 ?g/mg, respectively). A total of 46 metabolites were identified from seeds by gas chromatography-time-of-flight mass spectrometry. The metabolite profiles were subjected to principal component analysis (PCA). PCA could clearly differentiate the original and high-rutin cultivars. Our results indicate that the high-rutin cultivar could be an excellent alternative for buckwheat culture, and we provide useful information for obtaining this cultivar.
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IL-32? down-regulates ?2 integrin (CD18) expression by suppressing PU.1 expression in myeloid cells.
Cell. Signal.
PUBLISHED: 03-06-2014
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Myeloid-specific CD18 associates with CD11 and plays a critical role in leukocyte adhesion to the endothelium. In this study, we observed that CD18 expression was decreased by IL-32? in THP-1 and K562 cells upon PMA stimulation, and investigated the mechanism by which IL-32? down-regulated CD18 expression. We found that IL-32? suppressed the expression of PU.1, a major transcription factor for CD18. Because we previously demonstrated that IL-32? mediated STAT3 S727 phosphorylation by PKC?, and STAT3 regulates PU.1 expression, we performed time-course analyses of STAT3 S727 phosphorylation and found that IL-32? induces prolonged phosphorylation of STAT3 S727 until 72h after PMA stimulation. The expression pattern of C/EBP?, another transcriptional regulator of PU.1, was not affected by IL-32?. In addition, we showed that STAT3 binding to the PU.1 promoter was suppressed by IL-32?. Thus, we examined the relatedness among these factors and found that IL-32?-mediated STAT3 S727 phosphorylation induced C/EBP? association. When STAT3 was mutated at S727 to proline (S727P), the mutant STAT3 S727P did not interact with C/EBP?. We further demonstrated that only the intact STAT3 interacted with the basic leucine zipper region of C/EBP?. The PU.1 promoter was activated by co-expression of STAT3 and IL-32? upon PMA stimulation. However, the promoter activity was inhibited with STAT3 and C/EBP? co-expression. Therefore, our data suggest that IL-32?-mediated STAT3 S727 phosphorylation induced C/EBP? association, which inhibited PU.1 expression, and then resulted in the down-regulation of CD18 expression.
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Comparison of hormonal receptor and HER2 status between ultrasound-guided 14-gauge core needle biopsy and surgery in breast cancer patients.
Ultrasonography
PUBLISHED: 03-03-2014
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To evaluate the concordance of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) statuses between ultrasound (US)-guided 14-gauge core needle biopsy (CNB) and surgery and to analyze whether the clinicopathological and imaging features including those from mammography and ultrasonography can predict the concordance in breast cancer patients.
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IL-32? negatively regulates IL-1? production through its interaction with PKC? and the inhibition of PU.1 phosphorylation.
FEBS Lett.
PUBLISHED: 03-03-2014
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It has been well known that IL-32 exerts pro-inflammatory effects on the various inflammatory diseases in clinical studies. Here, we confirmed that IL-32?, a new isoform of IL-32, decreased the phorbol 12-myristate 13-acetate (PMA)-induced IL-1? expression in THP-1 human myelomonocyte. We previously reported that the IL-32 isoforms control expressions of other cytokines via novel PKCs. Likewise, IL-32? interacted with PKC?, and consequently inhibited PKC?-mediated phosphorylation of PU.1. Moreover, IL-32? attenuated the localization of PU.1 into the IL-1? promoter region. These findings reveal that IL-32? reduces PKC?-mediated phosphorylation of PU.1, resulting in attenuation of IL-1? production.
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Transferring MBE-grown topological insulator films to arbitrary substrates and metal-insulator transition via Dirac gap.
Nano Lett.
PUBLISHED: 03-03-2014
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Mechanical exfoliation of bulk crystals has been widely used to obtain thin topological insulator (TI) flakes for device fabrication. However, such a process produces only microsized flakes that are highly irregular in shape and thickness. In this work, we developed a process to transfer the entire area of TI Bi2Se3 thin films grown epitaxially on Al2O3 and SiO2 to arbitrary substrates, maintaining their pristine morphology and crystallinity. Transport measurements show that these transferred films have lower carrier concentrations and comparable or higher mobilities than before the transfer. Furthermore, using this process we demonstrated a clear metal-insulator transition in an ultrathin Bi2Se3 film by gate-tuning its Fermi level into the hybridization gap formed at the Dirac point. The ability to transfer large area TI films to any substrate will facilitate fabrication of TI heterostructure devices, which will help explore exotic phenomena such as Majorana fermions and topological magnetoelectricity.
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Tonicity-responsive enhancer binding protein regulates the expression of aldose reductase and protein kinase C ? in a mouse model of diabetic retinopathy.
Exp. Eye Res.
PUBLISHED: 02-24-2014
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Recent studies revealed that Tonicity-responsive enhancer binding protein (TonEBP) directly regulates the transcription of aldose reductase (AR), which catalyzes the first step of the polyol pathway of glucose metabolism. Activation of protein kinase C ? (PKC?) is dependent on AR and it has been linked to diabetic complications. However, whether TonEBP affects expressions of AR and PKC? in diabetic retinopathy was not clearly shown. In this study, we used TonEBP heterozygote mice to study the role of TonEBP in streptozotocin (STZ)-induced diabetic retinopathy. We performed immunofluorescence staining and found that retinal expressions of AR and PKC? were significantly reduced in the heterozygotes compared to wild type littermates, particularly in ganglion cell layer. To examine further the effect of TonEBP reduction in retinal tissues, we performed intravitreal injection of TonEBP siRNA and confirmed the decrease in AR and PKC? levels. In addition, we found that a proapoptotic factor, Bax level was reduced and a survival factor, Bcl2 level was increased after injection of TonEBP siRNA, indicating that TonEBP mediates apoptotic cell death. In parallel, TonEBP siRNA was applied to the in vitro human retinal pigment epithelial (ARPE-19) cells cultured in high glucose media. We have consistently found the decrease in AR and PKC? levels and changes in apoptotic factors for survival. Together, these results clearly demonstrated that hyperglycemia-induced TonEBP plays a crucial role in increasing AR and PKC? levels and leading to apoptotic death. Our findings suggest that TonEBP reduction is an effective therapeutic strategy for diabetic retinopathy.
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Seroprevalence of Plasmodium vivax in the Republic of Korea (2003-2005) using indirect fluorescent antibody test.
Korean J. Parasitol.
PUBLISHED: 02-19-2014
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Plasmodium vivax reemerged in the Republic of Korea (ROK) in 1993, and is likely to continue to affect public health. The purpose of this study was to measure levels of anti-P. vivax antibodies using indirect fluorescent antibody test (IFAT) in border areas of ROK, to determine the seroprevalence of malaria (2003-2005) and to plan effective control strategies. Blood samples of the inhabitants in Gimpo-si, Paju-si, and Yeoncheon-gun (Gyeonggi-do), and Cheorwon-gun (Gangwon-do) were collected and kept in Korea Centers for Disease Control and Prevention (KCDC). Out of a total of 1,774 serum samples tested, the overall seropositivity was 0.94% (n=17). The seropositivity was the highest in Paju-si (1.9%, 7/372), followed by Gimpo-si (1.4%, 6/425), Yeoncheon-gun (0.67%, 3/451), and Cheorwon-gun (0.19%, 1/526). The annual parasite incidence (API) in these areas gradually decreased from 2003 to 2005 (1.69, 1.09, and 0.80 in 2003, 2004, and 2005, respectively). The highest API was found in Yeoncheon-gun, followed by Cheorwon-gun, Paju-si, and Gimpo-si. The API ranking in these areas did not change over the 3 years. The seropositivity of Gimpo-si showed a strong linear relationship with the API of 2005 (r=0.9983, P=0.036). Seropositivity data obtained using IFAT may be useful for understanding malaria prevalence of relevant years, predicting future transmission of malaria, and for establishing and evaluating malaria control programs in affected areas.
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Hypoxia inducible factor-1? directly regulates nuclear clusterin transcription by interacting with hypoxia response elements in the clusterin promoter.
Mol. Cells
PUBLISHED: 02-19-2014
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Differential transcription of the clusterin (CLU) gene yields two CLU isoforms, a nuclear form (nCLU) and a secretory form (sCLU), which play crucial roles in prostate tumorigenesis. Pro-apoptotic nCLU and anti-apoptotic sCLU have opposite effects and are differentially expressed in normal and cancer cells; however, their regulatory mechanisms at the transcriptional level are not yet known. Here, we examined the transcriptional regulation of nCLU in response to hypoxia. We identified three putative hypoxia response elements (HREs) in the human CLU promoter between positions -806 and +51 bp. Using a luciferase reporter, electrophoretic gel mobility shift, and chromatin immunoprecipitation assays, we further showed that hypoxia-inducible factor-1? (HIF-1?) bound directly to these sites and activated transcription. Exposure to the hypoxiamimetic compound CoCl?, incubation under 1% O? conditions, or overexpression of HIF-1? enhanced nCLU expression and induced apoptosis in human prostate cancer PC3M cells. However, LNCaP prostate cancer cells were resistant to hypoxia-induced cell death. Methylation-specific PCR analysis revealed that the CLU promoter in PC3M cells was not methylated; in contrast, the CLU promoter in LNCap cells was methylated. Co-treatment of LNCaP cells with CoCl? and a demethylating agent promoted apoptotic cell death through the induction of nCLU. We conclude that nCLU expression is regulated by direct binding of HIF-1? to HRE sites and is epigenetically controlled by methylation of its promoter region.
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Thyroid nodules with macrocalcification: sonographic findings predictive of malignancy.
Yonsei Med. J.
PUBLISHED: 02-18-2014
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To analyze which sonographic features of thyroid nodules with macrocalcifications were predictable of thyroid malignancy.
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Risk factors for recurrence after therapeutic lateral neck dissection for primary papillary thyroid cancer.
Ann. Surg. Oncol.
PUBLISHED: 02-11-2014
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Lateral lymph node metastasis is an important prognostic factor and is predictive of tumor recurrence and cause-specific survival in patients with papillary thyroid cancer (PTC). However, the factors predicting recurrence and clinical outcomes after therapeutic lateral neck dissection are not well established. The aims of this study were to evaluate the incidence, pattern, and factors predictive of PTC recurrence after therapeutic lateral neck dissection.
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Activation of YAP1 is associated with poor prognosis and response to taxanes in ovarian cancer.
Anticancer Res.
PUBLISHED: 02-11-2014
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We aimed to investigate the clinical significance of the activation of Yes-Associated Protein 1 (YAP1), a key downstream effector of Hippo tumor-suppressor pathway, in ovarian cancer.
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Luteolin induces intrinsic apoptosis via inhibition of E6/E7 oncogenes and activation of extrinsic and intrinsic signaling pathways in HPV-18-associated cells.
Oncol. Rep.
PUBLISHED: 01-23-2014
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Luteolin, a flavonoid extracted from a number of plants with recognized anticancer, anti-inflammatory and anti-oxidative activities, inhibits angiogenic processes and modulates multidrug resistance. However, the efficacy and mechanisms of action of this flavonoid agent are still undergoing study. In order to elucidate whether luteolin exhibits an anticancer effect in cervical cancer cells, HeLa cells were incubated with luteolin and apoptosis was assessed by observing nuclear morphological changes, and performing Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. Cell cycle analysis, western blotting, RT-PCR and mitochondrial membrane potential measurements were also carried out. Luteolin showed a significant dose-dependent cytotoxic effect only in human papillomavirus (HPV)-positive cervical cancer cells, when compared to its effect on HPV-negative cervical cancer C33A cells. Expression levels of human papilloma virus E6 and E7 oncogenes were suppressed, those of related factors pRb and p53 were recovered and E2F5 was increased by luteolin treatment. Furthermore, luteolin enhanced the expression of death receptors and death receptor downstream factors such as Fas/FasL, DR5/TRAIL and FADD in HeLa cells, and activated caspase cascades. In particular, luteolin enhanced the activity of caspase-3 and -8 in a dose-dependent manner. Activation of caspase-3 induced caspase-8 activity and vice versa. Luteolin also induced mitochondrial membrane potential collapse and cytochrome c release, and inhibited Bcl-2 and Bcl-xL expression. In conclusion, luteolin exerts anticarcinogenic activity through inhibition of E6 and E7 expression and cross-activation of caspase-3 and -8. Taken together, these results suggest that luteolin induces inactivation of HPV-18 oncogene expression and apoptosis by activating the intrinsic and extrinsic pathways.
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Outcomes of Pneumocystis pneumonia with respiratory failure in HIV-negative patients.
J Crit Care
PUBLISHED: 01-21-2014
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The outcomes and predictors of mortality from Pneumocystis pneumonia (PCP) in HIV-negative patients requiring mechanical ventilation (MV) for respiratory failure were evaluated.
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Interaction network mapping among IL-32 isoforms.
Biochimie
PUBLISHED: 01-17-2014
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IL-32 has been studied for its pleiotropic effects ranging from host immune responses to cell differentiation. Although several IL-32 isoforms have been characterized for their effects on cells, the roles of the others remain unclear. We previously reported that IL-32? interacted with IL-32? and inhibited IL-32?-mediated IL-10 production. Thus, we performed comprehensive analyses to reveal more interactions between IL-32 isoforms in this study. We screened the interactions of 81 combinations of nine IL-32 isoforms by using a yeast two-hybrid assay, which identified 13 heterodimeric interactions. We verified these results by using reciprocal immunoprecipitation assays and reconfirmed 10 interactions, and presented the interaction network map between IL-32 isoforms. Our data suggest that IL-32 may have diverse intracellular effects through the interactions with its different isoforms.
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Serum galactomannan antigen test for the diagnosis of chronic pulmonary aspergillosis.
J. Infect.
PUBLISHED: 01-03-2014
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A serum galactomannan (GM) antigen test has been widely used to diagnose invasive pulmonary aspergillosis. However, there are limited data on the use of the serum GM antigen test for the serologic diagnosis of chronic pulmonary aspergillosis (CPA).
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Identification of regulatory factors for mesenchymal stem cell-derived salivary epithelial cells in a co-culture system.
PLoS ONE
PUBLISHED: 01-01-2014
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Patients with Sjögren's syndrome or head and neck cancer patients who have undergone radiation therapy suffer from severe dry mouth (xerostomia) due to salivary exocrine cell death. Regeneration of the salivary glands requires a better understanding of regulatory mechanisms by which stem cells differentiate into exocrine cells. In our study, bone marrow-derived mesenchymal stem cells were co-cultured with primary salivary epithelial cells from C57BL/6 mice. Co-cultured bone marrow-derived mesenchymal stem cells clearly resembled salivary epithelial cells, as confirmed by strong expression of salivary gland epithelial cell-specific markers, such as alpha-amylase, muscarinic type 3 receptor, aquaporin-5, and cytokeratin 19. To identify regulatory factors involved in this differentiation, transdifferentiated mesenchymal stem cells were analyzed temporarily by two-dimensional-gel-electrophoresis, which detected 58 protein spots (>1.5 fold change, p<0.05) that were further categorized into 12 temporal expression patterns. Of those proteins only induced in differentiated mesenchymal stem cells, ankryin-repeat-domain-containing-protein 56, high-mobility-group-protein 20B, and transcription factor E2a were selected as putative regulatory factors for mesenchymal stem cell transdifferentiation based on putative roles in salivary gland development. Induction of these molecules was confirmed by RT-PCR and western blotting on separate sets of co-cultured mesenchymal stem cells. In conclusion, our study is the first to identify differentially expressed proteins that are implicated in mesenchymal stem cell differentiation into salivary gland epithelial cells. Further investigation to elucidate regulatory roles of these three transcription factors in mesenchymal stem cell reprogramming will provide a critical foundation for a novel cell-based regenerative therapy for patients with xerostomia.
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Associations of the BRAFV600E Mutation with Sonographic Features and Clinicopathologic Characteristics in a Large Population with Conventional Papillary Thyroid Carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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To evaluate the association of the BRAFV600E mutation with sonographic features and clinicopathologic characteristics in a large population with conventional papillary thyroid carcinoma (PTC).
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Importance of Reciprocal Balance of T Cell Immunity in Mycobacterium abscessus Complex Lung Disease.
PLoS ONE
PUBLISHED: 01-01-2014
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Little is known about the nature of the host immune response to Mycobacterium abscessus complex (MABC) infection. The aim of the present study was to investigate whether alterations in serum immunomolecule levels after treating MABC lung disease patients with antibiotics can reflect the disease-associated characteristics.
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Genome-wide transcriptome profiling of homologous recombination DNA repair.
Nat Commun
PUBLISHED: 01-01-2014
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Homologous recombination (HR) repair deficiency predisposes to cancer development, but also sensitizes cancer cells to DNA damage-inducing therapeutics. Here we identify an HR defect (HRD) gene signature that can be used to functionally assess HR repair status without interrogating individual genetic alterations in cells. By using this HRD gene signature as a functional network analysis tool, we discover that simultaneous loss of two major tumour suppressors BRCA1 and PTEN extensively rewire the HR repair-deficient phenotype, which is found in cells with defects in either BRCA1 or PTEN alone. Moreover, the HRD gene signature serves as an effective drug discovery platform to identify agents targeting HR repair as potential chemo/radio sensitizers. More importantly, this HRD gene signature is able to predict clinical outcomes across multiple cancer lineages. Our findings, therefore, provide a molecular profile of HR repair to assess its status at a functional network level, which can provide both biological insights and have clinical implications in cancer.
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Clinical significance of Mycobacterium szulgai isolates from respiratory specimens.
Scand. J. Infect. Dis.
PUBLISHED: 12-20-2013
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Background: The clinical relevance of Mycobacterium szulgai respiratory isolates has been controversial. The aim of this study was to determine the clinical significance of M. szulgai isolates from respiratory specimens and to identify the clinical features and outcomes of M. szulgai lung disease. Methods: We reviewed the medical records of 30 patients from whom M. szulgai was isolated between 2001 and 2010 at the Samsung Medical Center (Seoul, Korea). Results: Of the 30 patients, 13 (43%) met the American Thoracic Society diagnostic criteria and were thus likely to have true M. szulgai lung disease. Approximately 57% (17/30) of M. szulgai isolates were recovered only once from patients with other pulmonary diseases, such as pulmonary tuberculosis and other non-tuberculous mycobacterial lung diseases. The 13 patients with M. szulgai lung disease included 12 men (92%), and the median age was 63 y. Among them, 7 (54%) were current smokers and 7 (54%) had a history of previous treatment for tuberculosis. Eight (62%) patients had the fibrocavitary form of M. szulgai lung disease. Nine (69%) patients received anti-mycobacterial treatment for a median duration of 8 months. Conversion to negative cultures was documented in all patients. There was no recurrence or disease-related mortality. Conclusions: Because the isolated M. szulgai from respiratory specimens could be regarded as pathogenic in less than 50% of cases, strict adherence to the recommended diagnostic criteria of non-tuberculous mycobacterial lung disease is essential.
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Graded synthetic approach for the fabrication of nanocrystal quantum dots for enhanced carrier injection in light-emitting diodes.
Nanotechnology
PUBLISHED: 11-27-2013
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A synthetic approach for fabricating compositionally graded multishell nanocrystal quantum dots (NQDs) from cubic CdSe is presented. The structural shapes with each shell formation were examined using scanning transmission electron microscopy (STEM) coupled with energy dispersive x-ray spectroscopy and electron energy loss spectroscopy (EELS). The optical properties probed via time-resolved spectroscopy further revealed detailed carrier behavior at the core/graded shell interface. A highly luminescing stable optical device was built using our graded multishell NQDs.
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Club cell protein 16 and disease progression in chronic obstructive pulmonary disease.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 11-20-2013
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Rationale: Club (Clara) cell protein 16 (CC-16) is a protein that is synthesized predominantly in the lungs and is detectable in serum. Its expression decreases with lung injury and smoking, and is thus a marker of bronchial cell dysfunction. Objectives: To evaluate the possibility of using serum CC-16 as a biomarker for disease progression in chronic obstructive pulmonary disease (COPD). Methods: We measured serum CC-16 levels from 4,724 subjects with mild-to-moderate airflow limitation in the Lung Health Study. Using a linear regression model, we determined the relationship of serum CC-16 concentrations to decline in lung function over 9 years. In addition, to determine whether CC-16 plays a major role in the pathogenesis of mild COPD, we exposed CC-16-deficient (-/-) mice to 6 months of cigarette smoke. Measurements and Main Results: Reduced serum concentrations of CC-16 were associated with accelerated decline in FEV1 over 9 years (P < 0.0001), and this association persisted after adjustments for age, sex, race, smoking status, airway reactivity, body mass index, and baseline FEV1 (P = 0.0002). However, CC-16(-/-) mice did not demonstrate an enhanced risk of emphysema or small airway remodeling in response to cigarette smoke. Conclusions: Serum CC-16 is associated with disease progression, and may assist in the identification of "rapid progressors." However, the absence of CC-16 does not appear to modify the risk of cigarette-related COPD in mice.
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Evaluation of circumsporozoite protein of Plasmodium vivax to estimate its prevalence in the Republic of Korea: an observational study of incidence.
Malar. J.
PUBLISHED: 11-17-2013
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Plasmodium vivax re-emerged in 1993. Although the number of infections has been steadily decreasing, it is likely to continue to affect public health until it is eradicated. The aim of this study is to measure anti-circumsporozoite protein (CSP) antibody and compare malaria prevalence. As to understand the prevalence, an epidemiology study has to be conducted in the Republic of Korea.
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Metabolic Differentiation of Diamondback Moth ( Plutella xylostella (L.)) Resistance in Cabbage ( Brassica oleracea L. ssp. capitata).
J. Agric. Food Chem.
PUBLISHED: 11-07-2013
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The diamondback moth, Plutella xylostella (L.), is a major pest responsible for destroying cabbage and other Brassica vegetable crops. A diamondback moth-resistant cabbage line was studied by comparing its metabolite profiles with those of a susceptible cabbage. Fourier transform infrared spectroscopy analysis revealed that carbohydrates, aromatic compounds, and amides were the major factors that distinguished the resistant and susceptible genotypes. Gas chromatography-time-of-flight mass spectrometry profiled 46 metabolites, including 19 amino acids, 15 organic acids, 8 sugars, 3 sugar alcohols, and 1 amine in two genotypes and F1 hybrid cabbages. The levels of glycolic acid, quinic acid, inositol, fumaric acid, glyceric acid, trehalose, shikimic acid, and aspartic acid were found to be very significantly different between the resistant and susceptible genotypes with a P value of <0.0001. These results will provide a foundation for further studies on diamondback moth resistance in cabbage breeding and for the development of other herbivore-resistant crops.
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Metabolomic analysis and differential expression of anthocyanin biosynthetic genes in white- and red-flowered buckwheat cultivars (Fagopyrum esculentum).
J. Agric. Food Chem.
PUBLISHED: 10-23-2013
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Red-flowered buckwheat ( Fagopyrum esculentum ) is used in the production of tea, juice, and alcohols after the detoxification of fagopyrin. In order to investigate the metabolomics and regulatory of anthocyanin production in red-flowered (Gan-Chao) and white-flowered (Tanno) buckwheat cultivars, quantitative real-time RT-PCR (qRT-PCR), gas chromatography time-of-flight mass spectrometry (GC-TOFMS), and high performance liquid chromatography (HPLC) were conducted. The transcriptions of FePAL, FeC4H, Fe4CL1, FeF3H, FeANS, and FeDFR increased gradually from flowering stage 1 and reached their highest peaks at flowering stage 3 in Gan-Chao flower. In total 44 metabolites, 18 amino acids, 15 organic acids, 7 sugars, 3 sugar alcohols, and 1 amine were detected in Gan-Chao flowers. Two anthocyanins, cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside, were identified in Gan-Chao cultivar. The first component of the partial least-squares to latent structures-discriminate analysis (PLS-DA) indicated that high amounts of phenolic, shikimic, and pyruvic acids were present in Gan-Chao. We suggest that transcriptions of genes involved in anthocyanin biosynthesis, anthocyanin contents, and metabolites have correlation in the red-flowered buckwheat Gan-Chao flowers. Our results may be helpful to understand anthocyanin biosynthesis in red-flowered buckwheat.
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Transmission electron microscopy study of microstructural properties and dislocation characterization in the GaN film grown on the cone-shaped patterned Al2O3 substrate.
Microscopy (Oxf)
PUBLISHED: 10-09-2013
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Growing a GaN film on a patterned Al2O3 substrate is one of the methods of reducing threading dislocations (TDs), which can significantly deteriorate the performance of GaN-based LEDs. In this study, the microstructural details of the GaN film grown on a cone-shaped patterned Al2O3 substrate were investigated using high-resolution transmission electron microscopy and weak-beam dark-field techniques. Various defects such as misfit dislocations (MDs), recrystallized GaN (R-GaN) islands and nano-voids were observed on the patterned Al2O3 surfaces, i.e. the flat surface (FS), the inclined surface (IS) and the top surface (TS), respectively. Especially, the crystallographic orientation of R-GaN between the GaN film and the inclined Al2O3 substrate was identified as , . In addition, a rotation by 9° between and and between and was found to reduce the lattice mismatch between the GaN film and the Al2O3 substrate. Many TDs in the GaN film were observed on the FS and TS of Al2O3. However, few TDs were observed on the IS. Most of the TDs generated from the FS of Al2O3 were bent to the inclined facet rather than propagating to the GaN surface, resulting in a reduction in the dislocation density. Most of the TDs generated from the TS of Al2O3 were characterized as edge dislocations.
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Asthma and severity of the 2009 novel H1N1 influenza: a case-control study.
J Asthma
PUBLISHED: 10-08-2013
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Abstract Objective: Previous studies reported that the most common chronic condition found among hospitalized patients due to the novel 2009 H1N1 influenza was asthma. However, these studies did not include a concurrent control group. Thus, we investigated the association of asthma status and severity of H1N1 influenza in adults. Methods: The study was designed as a multi-site case-control study. Cases were patients who had positive PCR for H1N1 influenza and were admitted to the ICU or general ward with a diagnosis of H1N1 influenza from 1 January 2009 to 31 December 2009. Controls were patients who had positive PCR for H1N1 influenza, but were not admitted to hospitals. Results: There were 91 H1N1 cases admitted to either ICU (n?=?41) or general hospital ward (n?=?50), and 56 controls who met the matching criteria were available. Of the 91 cases, the mean age was 47.3 years, 59% were female, and 38% had comorbid conditions. Of the 91 cases, 12 (13%) had asthma. Stratified analysis by comorbid conditions showed that among those without any comorbid conditions, 8 of 56 cases (14%) and 2 of 49 controls (4%) had asthma, (OR: 3.92, 95% CI: 0.79-19.42, p?=?0.095) whereas, among the 39 subjects with one or more comorbid conditions, one of 7 controls (14%) had asthma and 4 of 35 (11%) cases had asthma (p?=?0.83). Conclusions: Asthma may be associated with severity of H1N1 influenza among those without any non-asthma comorbid conditions. However, the limited sample size did not allow this study to fully establish statistical significance. We still recommend asthmatics as a priority group for influenza vaccination and treatment.
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Extent of Mycobacterium bovis Infection in Dairy Cattle Herds Subject to Partial Culling as Determined by an Interferon-Gamma Assay.
J. Vet. Sci.
PUBLISHED: 09-27-2013
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The interferon-gamma (IFN-?) assay has been employed as a complementary diagnostic test for bovine tuberculosis (BTB) in many countries. In order to simplify this assay, we established a 96-well plate format using the ESAT-6 and CFP-10 antigens and used it to determine the extent of Mycobacterium bovis infection in dairy herds with a history of BTB outbreaks in a country where only selective culling is practiced. The sensitivity and specificity of this IFN-? assay were 85.9% and 100%, respectively, based on a comparison with the conventional single intradermal tuberculin test (SIDT). The IFN-? assay was also positive in 30.4% and 36.8% of SIDT-negative animals from herds with recent and remote BTB outbreaks, respectively. Of 14 SIDT-negative, IFN-? positive cattle, 5 (35.7%) were culture positive and an additional 6 were positive by a polymerase chain reaction-based test for M. bovis. Therefore, the IFN-? assay potentially provides a specific and sensitive test for M. bovis infection in dairy cattle. Further, based on the results obtained from this assay, a substantial portion of SIDT-negative animals in herds with previous BTB outbreaks were actually infected with M. bovis. The present selective-culling strategy may require modifications to include this more sensitive assay.
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The role of endobronchial ultrasound-guided transbronchial needle aspiration in the diagnosis of recurrent non-small cell lung cancer after surgery.
Intern. Med.
PUBLISHED: 09-03-2013
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Obtaining an accurate histopathological diagnosis is mandatory for the optimal treatment of patients who are suspected of having recurrent lung cancer. The purpose of this retrospective study was to investigate the usefulness of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for the diagnosis of recurrent non-small cell lung cancer (NSCLC) among patients who undergo curative surgical resection.
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Repeated derecruitments accentuate lung injury during mechanical ventilation*.
Crit. Care Med.
PUBLISHED: 08-22-2013
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The aim of our study was to assess whether repeated derecruitments induced by the repetitive withdrawal of high positive end-expiratory pressure could induce lung injury in a swine model.
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The novel, actin-like protein Tact3 is expressed in rodent testicular haploid germ cells.
Mol. Reprod. Dev.
PUBLISHED: 08-16-2013
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Mouse testis actin-like proteins 1 and 2 (mTact1 and mTact2), which are expressed in the mouse haploid germ cells, have been described previously. Here, we report the cloning and characterization of a third actin-like protein from rat, rat testis actin-like protein 3 (rTact3). The complete cDNA of the rTact3 gene was approximately 3.7?kb in length, and its corresponding amino acid sequence consisted of 1219 amino acids. The rTact3 gene lacks introns, similar to mTact1 and mTact2. The 356 C-terminal amino acids of rTact3 showed 43% homology with mTact1, whereas the 863 N-terminal amino acids did not show any significant homology. Northern blot analysis revealed that rTact3 mRNA was expressed only in adult rat testes and not during the prepubescent stage. In situ hybridization revealed that rTact3 was expressed exclusively during round and elongated spermatids maturation stages in rat testes. Immunohistochemical experiments using antibodies raised against a synthetic peptide showed that the expression of the rTact3 protein was also restricted in round and elongated spermatids, specifically in the head and acrosome of mature rat sperm. The 5-flanking region of the mTact3 gene was found to contain a TATA-box motif as well as two putative CREB/c-Jun and five C/EBP motifs. mTact3 promoter activity was enhanced in a dose-dependent manner by the transfection of CREB, c-Jun, or C/EBP in NIH3T3 cells. These results suggest that Tact3 proteins might play an important role in rodent germ-cell development. Mol. Reprod. Dev. © 2013 Wiley Periodicals, Inc.
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Microscopic and spectroscopic analyses of Pt-decorated carbon nanowires formed on carbon fiber paper.
Microsc. Microanal.
PUBLISHED: 08-08-2013
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We report the synthesis of carbon nanowires (CNWs) via chemical vapor deposition using catalytic decomposition of ethanol on nanosized transition metals such as Co, Fe, and Ni. Dip-coating process was used for the formation of catalytic nanoparticles, inducing the growth of CNWs on the surface of the carbon fiber paper (CFP). The liquid ethanol used as carbon source was atomized by an ultrasonic atomizer and subsequently flowed into the reactor that was heated up to a synthesis temperature of 600-700°C. Microscopic images show that CNWs of <50 nm were densely synthesized on the surface of the CFP. Raman spectra reveal that a higher synthesis temperature leads to the growth of higher crystalline CNWs. In addition, we demonstrate the successful decoration of platinum nanoparticles on the surface of the prepared CNWs/CFP using the electrochemical deposition technique.
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Microstructural characterization of high indium-composition InXGa?-XN epilayers grown on c-plane sapphire substrates.
Microsc. Microanal.
PUBLISHED: 08-08-2013
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The growth of high-quality indium (In)-rich In(X)Ga(1-X)N alloys is technologically important for applications to attain highly efficient green light-emitting diodes and solar cells. However, phase separation and composition modulation in In-rich In(X )Ga(1-X)N alloys are inevitable phenomena that degrade the crystal quality of In-rich In(X)Ga(1-X)N layers. Composition modulations were observed in the In-rich In(X)Ga(1-X)N layers with various In compositions. The In composition modulation in the In X Ga1-X N alloys formed in samples with In compositions exceeding 47%. The misfit strain between the InGaN layer and the GaN buffer retarded the composition modulation, which resulted in the formation of modulated regions 100 nm above the In(0.67)Ga(0.33)N/GaN interface. The composition modulations were formed on the specific crystallographic planes of both the {0001} and {0114} planes of InGaN.
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Development of a polymerase chain reaction applicable to rapid and sensitive detection of Clonorchis sinensis eggs in human stool samples.
Pathog Glob Health
PUBLISHED: 08-07-2013
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Microscopic examination of eggs of parasitic helminths in stool samples has been the most widely used classical diagnostic method for infections, but tiny and low numbers of eggs in stool samples often hamper diagnosis of helminthic infections with classical microscopic examination. Moreover, it is also difficult to differentiate parasite eggs by the classical method, if they have similar morphological characteristics. In this study, we developed a rapid and sensitive polymerase chain reaction (PCR)-based molecular diagnostic method for detection of Clonorchis sinensis eggs in stool samples. Nine primers were designed based on the long-terminal repeat (LTR) of C. sinensis retrotransposon1 (CsRn1) gene, and seven PCR primer sets were paired. Polymerase chain reaction with each primer pair produced specific amplicons for C. sinensis, but not for other trematodes including Metagonimus yokogawai and Paragonimus westermani. Particularly, three primer sets were able to detect 10 C. sinensis eggs and were applicable to amplify specific amplicons from DNA samples purified from stool of C. sinensis-infected patients. This PCR method could be useful for diagnosis of C. sinensis infections in human stool samples with a high level of specificity and sensitivity.
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Wogonin induces apoptosis by suppressing E6 and E7 expressions and activating intrinsic signaling pathways in HPV-16 cervical cancer cells.
Cell Biol. Toxicol.
PUBLISHED: 07-22-2013
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Wogonin is a flavonoid compound extracted from Scutellaria baicalensis and is well known as a benzodiazepine receptor ligand with anxiolytic effects. Many recent studies have demonstrated that wogonin modulates angiogenesis, proliferation, invasion, and tumor progress in various cancer tissues. We further explored the mechanism of action of wogonin on cervical cancer cells that contain or lack human papillomavirus (HPV) DNA. Wogonin was cytotoxic to HPV 16 (+) cervical cancer cells, SiHa and CaSki, but not to HPV-negative cells. We demonstrated that wogonin induced apoptosis by suppressing the expressions of the E6 and E7 viral oncogenes in HPV-infected cervical cancer CaSki and SiHa cells. The modulation of p53 and protein retinoblastoma (pRb) were also triggered by the suppression of E6 and E7 expressions. However, p53 was not altered in HPV-negative cervical cancer C33A cells. Moreover, wogonin modulated the mitochondrial membrane potential and the expression of pro- and anti-apoptotic factors such as Bax and Bcl-2. Wogonin also provoked the cleavage of caspase-3, caspase-9, and poly ADP ribose polymerase. After transfection of siRNAs to target E6 and E7, additional restoration of p53 and pRb was not induced, but processing of caspases and PARP was increased compared with wogonin treatment alone. Together, our findings demonstrated that wogonin effectively promotes apoptosis by downregulating E6 and E7 expressions and promoting intrinsic apoptosis in human cervical cancer cells.
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Transparent films for heterojunction Si photovoltaics.
J Nanosci Nanotechnol
PUBLISHED: 07-19-2013
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A heterojunction of Al-doped ZnO (AZO) and Si was applied as a photodiode. A Co-sputtering system was used to deposit a quality AZO film following an n-type Si thin film coating. Al is an n-doping element for ZnO and thus the Al content significantly controls the mobility and the crystalline structure of AZO films. In order to provide the highest mobility, the optimum Al-content was found to be 5.22 wt%. X-ray diffraction analysis also showed a release of the compressive stress for the Al-5.22 wt% AZO film. Due to the excellent electrical conductivity of the AZO film, the heterojunction diode showed an enhanced rectifying ratio of 87.7 from 59.9 of the bare Si diode according to the reduction of the series resistance. This scheme may provide a route to reducing the contact resistance and subsequently improving photovoltaic devices.
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Decreasing incidence of Plasmodium vivax in the Republic of Korea during 2010-2012.
Malar. J.
PUBLISHED: 07-18-2013
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After the re-emergence of Plasmodium vivax in 1993, a total of 31,254 cases of vivax malaria were reported between 1993-2012 in the Republic of Korea (ROK). The purpose of this study was to review Korea Centers for Disease Control and Prevention records to investigate the transmission of malaria from 2010-2012.
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Metabolite profiling approach reveals the interface of primary and secondary metabolism in colored cauliflowers (Brassica oleracea L. ssp. botrytis).
J. Agric. Food Chem.
PUBLISHED: 07-05-2013
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In the present study, carotenoids, anthocyanins, and phenolic acids of cauliflowers ( Brassica oleracea L. ssp. botrytis) with various colored florets (white, yellow, green, and purple) were characterized to determine their phytochemical diversity. Additionally, 48 metabolites comprising amino acids, organic acids, sugars, and sugar alcohols were identified using gas chromatography-time-of-flight mass spectrometry (GC-TOFMS). Carotenoid content was considerably higher in green cauliflower; anthocyanins were detected only in purple cauliflower. Phenolic acids were higher in both green and purple cauliflower. Results of partial least-squares discriminant, Pearson correlation, and hierarchical clustering analyses showed that green cauliflower is distinct on the basis of the high levels of amino acids and clusters derived from common or closely related biochemical pathways. These results suggest that GC-TOFMS-based metabolite profiling, combined with chemometrics, is a useful tool for determining phenotypic variation and identifying metabolic networks connecting primary and secondary metabolism.
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Scaling Laws at the Nano Size: The Effect of Particle Size and Shape on the Magnetism and Relaxivity of Iron Oxide Nanoparticle Contrast Agents.
J Mater Chem B Mater Biol Med
PUBLISHED: 07-03-2013
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The magnetic properties of iron oxide nanoparticles govern their relaxivities and efficacy as contrast agents for MRI. These properties are in turn determined by their composition, size and morphology. Herein we present a systematic study of the effect of particle size and shape of magnetite nanocrystals synthesized by thermal decompositions of iron salts on both their magnetism and their longitudinal and transverse relaxivities, r 1 and r 2, respectively. Faceted nanoparticles demonstrate superior magnetism and relaxivities than spherical nanoparticles of similar size. For faceted nanoparticles, but not for spherical ones, r 1 and r 2 further increase with increasing particle size up to a size of 18 nm. This observation is in accordance with increasing saturation magnetization for nanoparticles increasing in size up to 12 nm, above which a plateau is observed. The NMRD (Nuclear Magnetic Resonance Dispersion) profiles of MIONs (Magnetic Iron Oxide Nanoparticles) display an increase in longitudinal relaxivity with decreasing magnetic field strength with a plateau below 1 MHz. The transverse relaxivity shows no dependence on the magnetic field strength between 20 MHz and 500 MHz. These observations translate to phantom MR images: in T 1-weighted SWIFT (SWeep imaging with Fourier Transform) images MIONs have a positive contrast with little dependence on particle size, whereas in T 2-weighted gradient-echo images MIONs create a negative contrast which increases in magnitude with increasing particle size. Altogether, these results will enable the development of particulate MRI contrast agents with enhanced efficacy for biomedical and clinical applications.
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Interleukin (IL)-32?-mediated CCAAT/enhancer-binding protein ? (C/EBP?) phosphorylation by protein kinase C? (PKC?) abrogates the inhibitory effect of C/EBP? on IL-10 production.
J. Biol. Chem.
PUBLISHED: 06-30-2013
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We previously reported that IL-32? promotes IL-10 production in myeloid cells. However, the underlying mechanism remains elusive. In this study, we demonstrated that IL-32? abrogated the inhibitory effect of CCAAT/enhancer-binding protein ? (C/EBP?) on IL-10 expression in U937 cells. We observed that the phosphorylation of C/EBP? Ser-21 was inhibited by a PKC?-specific inhibitor, rottlerin, or IL-32? knockdown by siRNA and that IL-32? shifted to the membrane from the cytosol upon phorbol 12-myristate 13-acetate treatment. We revealed that IL-32? suppressed the binding of C/EBP? to IL-10 promoter by using ChIP assay. These data suggest that PKC? and IL-32? may modulate the effect of C/EBP? on IL-10 expression. We next demonstrated by immunoprecipitation that IL-32? interacted with PKC? and C/EBP?, thereby mediating C/EBP? Ser-21 phosphorylation by PKC?. We showed that IL-32? suppressed the inhibitory effect of C/EBP? on IL-10 promoter activity. However, the IL-10 promoter activity was reduced to the basal level by rottlerin treatment. When C/EBP? serine 21 was mutated to glycine (S21G), the inhibitory effect of C/EBP? S21G on IL-10 promoter activity was not modulated by IL-32?. Taken together, our results show that IL-32?-mediated C/EBP? Ser-21 phosphorylation by PKC? suppressed C/EBP? binding to IL-10 promoter, which promoted IL-10 production in U937 cells.
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Focused-laser-enabled p-n junctions in graphene field-effect transistors.
ACS Nano
PUBLISHED: 06-21-2013
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With its electrical carrier type as well as carrier densities highly sensitive to light, graphene is potentially an ideal candidate for many optoelectronic applications. Beyond the direct light-graphene interactions, indirect effects arising from induced charge traps underneath the photoactive graphene arising from light-substrate interactions must be better understood and harnessed. Here, we study the local doping effect in graphene using focused-laser irradiation, which governs the trapping and ejecting behavior of the charge trap sites in the gate oxide. The local doping effect in graphene is manifested by large Dirac voltage shifts and/or double Dirac peaks from the electrical measurements and a strong photocurrent response due to the formation of a p-n-p junction in gate-dependent scanning photocurrent microscopy. The technique of focused-laser irradiation on a graphene device suggests a new method to control the charge-carrier type and carrier concentration in graphene in a nonintrusive manner as well as elucidate strong light-substrate interactions in the ultimate performance of graphene devices.
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Single-crystal apatite nanowires sheathed in graphitic shells: synthesis, characterization, and application.
ACS Nano
PUBLISHED: 06-17-2013
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Vertically aligned one-dimensional hybrid structures, which are composed of apatite and graphitic structures, can be beneficial for orthopedic applications. However, they are difficult to generate using the current method. Here, we report the first synthesis of a single-crystal apatite nanowire encapsulated in graphitic shells by a one-step chemical vapor deposition. Incipient nucleation of apatite and its subsequent transformation to an oriented crystal are directed by derived gaseous phosphorine. Longitudinal growth of the oriented apatite crystal is achieved by a vapor-solid growth mechanism, whereas lateral growth is suppressed by the graphitic layers formed through arrangement of the derived aromatic hydrocarbon molecules. We show that this unusual combination of the apatite crystal and the graphitic shells can lead to an excellent osteogenic differentiation and bony fusion through a programmed smart behavior. For instance, the graphitic shells are degraded after the initial cell growth promoted by the graphitic nanostructures, and the cells continue proliferation on the bare apatite nanowires. Furthermore, a bending experiment indicates that such core-shell nanowires exhibited a superior bending stiffness compared to single-crystal apatite nanowires without graphitic shells. The results suggest a new strategy and direction for bone grafting materials with a highly controllable morphology and material conditions that can best stimulate bone cell differentiation and growth.
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Timing of silicone stent removal in patients with post-tuberculosis bronchial stenosis.
Ann Thorac Med
PUBLISHED: 06-16-2013
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In patients with post-tuberculosis bronchial stenosis (PTBS), the severity of bronchial stenosis affects the restenosis rate after the silicone stent is removed. In PTBS patients with incomplete bronchial obstruction, who had a favorable prognosis, the timing of stent removal to ensure airway patency is not clear.
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Severe Rhabdomyolysis Associated With Concurrent Use of Simvastatin and Sirolimus After Cisplatin-Based Chemotherapy in a Kidney Transplant Recipient.
Exp Clin Transplant
PUBLISHED: 05-29-2013
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Objectives: Cardiovascular disease is the most common cause of sickness and death for long-term kidney transplant recipients, and dyslipidemia is an important risk factor for developing cardiovascular disease. Lipid-lowering strategies, with the use of statins, have been shown to reduce the cardiovascular risks related to dyslipidemia, but concomitant use of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors and immunosuppressive agents may increase the risk of rhabdomyolysis owing to a drug-drug interaction. We report a case of simvastatin-induced rhabdomyolysis and acute kidney injury triggered by addition of sirolimus and cisplatin-based chemotherapy to a kidney transplant recipient who had previously tolerated chronic statin therapy.
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A case of vivax malaria complicated by adult respiratory distress syndrome and successful management with extracorporeal membrane oxygenation.
Korean J. Parasitol.
PUBLISHED: 05-28-2013
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Complicated malaria is mainly caused by Plasmodium falciparum, but, increasingly, Plasmodium vivax is also being reported as a cause. Since the reemergence of indigenous vivax malaria in 1993, cases of severe malaria have been steadily reported in Korea. Herein, we report a case of vivax malaria complicated by adult respiratory distress syndrome (ARDS) that was successfully managed with extracorporeal membrane oxygenation (ECMO). A 59-year-old man presented at our hospital with fever and abdominal pain, which had persisted for 10 days. On admission, the patient had impaired consciousness, shock, hypoxia and haziness in both lungs, jaundice, thrombocytopenia and disseminated intravascular coagulation, metabolic acidosis, and acute kidney injury. A peripheral blood smear and a rapid diagnostic test verified P. vivax mono-infection. Ten hours after admission, hypoxia became more severe, despite providing maximal ventilatory support. The administration of antimalarial agents, ECMO, and continuous venovenous hemofiltration resulted in an improvement of his vital signs and laboratory findings. He was discharged from the hospital 7 weeks later, without any sequelae.
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Additional role of second washing specimen obtained during single bronchoscopy session in diagnosis of pulmonary tuberculosis.
BMC Infect. Dis.
PUBLISHED: 05-01-2013
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Flexible bronchoscopy with bronchial washing is a useful procedure for diagnosis of pulmonary tuberculosis (TB), when a patient cannot produce sputum spontaneously or when sputum smears are negative. However, the benefit of gaining serial bronchial washing specimens for diagnosis of TB has not yet been studied. Therefore, we conducted a retrospective study to determine the diagnostic utility of additional bronchial washing specimens for the diagnosis of pulmonary TB in suspected patients.
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Is Atrial Fibrillation Always a Culprit of Stroke in Patients with Atrial Fibrillation plus Stroke?
Cerebrovasc. Dis.
PUBLISHED: 04-15-2013
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Background: Some ischemic strokes in patients with atrial fibrillation (AF) are caused by noncardioembolic etiologies (AF-unrelated stroke), but not AF itself (AF-related stroke). However, most clinical trials on the risk of stroke in AF have not distinguished between these. We investigated the frequency and features of AF-unrelated versus AF-related strokes in patients with AF plus ischemic stroke. We hypothesized that certain clinical factors, including chronicity of AF, treatment at the time of stroke onset and echocardiographic findings, may help to discriminate between AF-related and AF-unrelated strokes. The mechanisms and antithrombotic medications at the time of stroke recurrence in the two groups were also examined. Methods: Consecutive patients with ischemic stroke within 7 days of symptom onset and with AF were included. Patients were classified according to the previously published criteria. Clinical factors including CHADS2 and CHA2DS2-VASc scores and transthoracic echocardiographic (TTE) findings were evaluated. Results: Of 522 patients, 424 (81.2%) were grouped as AF-related stroke and the remaining 90 (17.2%) were classified as AF-unrelated stroke. Among the patients with AF-unrelated stroke, 51 (9.8%) were categorized as possible large artery atherosclerosis and 38 (7.3%) as possible small artery occlusion; 1 patient (0.2%) was assigned to miscellaneous cause. The AF-related and AF-unrelated strokes had similar CHADS2 and CHA2DS2-VASc scores. However, compared to AF-unrelated stroke, AF-related stroke was independently associated with female sex (odds ratio, OR, 2.19; 95% confidence interval, CI, 1.18-4.05), sustained AF (OR, 2.09; 95% CI, 1.21-3.59), inadequate anticoagulation at stroke onset (OR, 3.21; 95% CI, 1.33-7.75) and left ventricular dysfunction on TTE (OR, 2.84; 95% CI, 1.40-5.74). We identified 26 patients who experienced 2 strokes during the study period. The initial stroke subtype was a strong predictor of the recurrent stroke mechanism (p < 0.001). Among 17 events of AF-related recurrent stroke in these subpopulation, only 2 strokes (11.8%) occurred in a setting of adequate anticoagulation, whereas 4 out of 9 patients (44.4%) who had AF-unrelated strokes at recurrence were sufficiently anticoagulated at the time of admission (p = 0.138). Conclusion: AF is not always a culprit of stroke in patients with AF plus ischemic stroke; approximately one sixth of these cases are unrelated to AF and have distinct characteristics compared to AF-related stroke. There are significant differences in terms of some clinical and TTE parameters between AF-related and AF-unrelated stroke. Future studies are warranted to optimize strategies for risk stratification, treatment and prevention of stroke in these patients. © 2013 S. Karger AG, Basel.
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Insight to the interaction of the dihydrolipoamide acetyltransferase (E2) core with the peripheral components in the Escherichia coli pyruvate dehydrogenase complex via multifaceted structural approaches.
J. Biol. Chem.
PUBLISHED: 04-11-2013
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Multifaceted structural approaches were undertaken to investigate interaction of the E2 component with E3 and E1 components from the Escherichia coli pyruvate dehydrogenase multienzyme complex (PDHc), as a representative of the PDHc from Gram-negative bacteria. The crystal structure of E3 at 2.5 ? resolution reveals similarity to other E3 structures and was an important starting point for understanding interaction surfaces between E3 and E2. Biochemical studies revealed that R129E-E2 and R150E-E2 substitutions in the peripheral subunit-binding domain (PSBD) of E2 greatly diminished PDHc activity, affected interactions with E3 and E1 components, and affected reductive acetylation of E2. Because crystal structures are unavailable for any complete E2-containing complexes, peptide-specific hydrogen/deuterium exchange mass spectrometry was used to identify loci of interactions between 3-lipoyl E2 and E3. Two peptides from the PSBD, including Arg-129, and three peptides from E3 displayed statistically significant reductions in deuterium uptake resulting from interaction between E3 and E2. Of the peptides identified on E3, two were from the catalytic site, and the third was from the interface domain, which for all known E3 structures is believed to interact with the PSBD. NMR clearly demonstrates that there is no change in the lipoyl domain structure on complexation with E3. This is the first instance where the entire wild-type E2 component was employed to understand interactions with E3. A model for PSBD-E3 binding was independently constructed and found to be consistent with the importance of Arg-129, as well as revealing other electrostatic interactions likely stabilizing this complex.
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The relationships between tracheal index and lung volume parameters in mild-to-moderate COPD.
Eur J Radiol
PUBLISHED: 04-09-2013
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Although elongated morphological changes in the trachea are known to be related to lung function in chronic obstructive pulmonary disease (COPD), whether the tracheal morphological changes are associated with airflow limitations or overinflation of the lung in the early stages of COPD has not yet been determined. Thus, our aim was to investigate the association of tracheal index (TI) with lung function parameters, including lung volume parameters, in COPD patients with mild-to-moderate airflow limitations.
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