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Find video protocols related to scientific articles indexed in Pubmed.
Large-Scale Production of Graphene Nanoribbons from Electrospun Polymers.
J. Am. Chem. Soc.
PUBLISHED: 11-20-2014
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Graphene nanoribbons (GNRs) are promising building blocks for high-performance electronics due to their high electron mobility and dimensionality-induced bandgap. Despite many past efforts, direct synthesis of GNRs with controlled dimensions and scalability remains challenging. Here we report the scalable synthesis of GNRs using electrospun polymer nanofibers templates. Palladium-incorporated poly-(4-vinylphenol) nanofibers were prepared by electrospinning with controlled diameter and orientation. Highly graphitized GNRs as narrow as 10 nm were then synthesized from these templates by chemical vapor deposition. A transport gap can be observed in 30-nm-wide GNRs, enabling them to function as field-effect transistors at room temperature. Our results represent the first success on the scalable synthesis of highly graphitized GNRs from polymer templates. Furthermore, the generality of this method allows various polymers to be explored, which will lead to understanding of growth mechanism and rational control over crystallinity, feature size and bandgap to enable a new pathway for graphene electronics.
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High Electrochemical Selectivity of Edge versus Terrace Sites in Two-Dimensional Layered MoS2 Materials.
Nano Lett.
PUBLISHED: 11-06-2014
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Exploring the chemical reactivity of different atomic sites on crystal surface and controlling their exposures are important for catalysis and renewable energy storage. Here, we use two-dimensional layered molybdenum disulfide (MoS2) to demonstrate the electrochemical selectivity of edge versus terrace sites for Li-S batteries and hydrogen evolution reaction (HER). Lithium sulfide (Li2S) nanoparticles decorates along the edges of the MoS2 nanosheet versus terrace, confirming the strong binding energies between Li2S and the edge sites and guiding the improved electrode design for Li-S batteries. We also provided clear comparison of HER activity between edge and terrace sites of MoS2 beyond the previous theoretical prediction and experimental proof.
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Progesterone receptor-NF?B complex formation is required for progesterone-induced NF?-B nuclear translocation and binding onto the p53 promoter.
Endocrinology
PUBLISHED: 10-30-2014
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We previously demonstrated that progesterone (P4) up-regulates p53 expression in human umbilical venous endothelial cells (HUVEC) through P4 receptor (PR) activation of extra-nuclear signaling pathways. However, the involvement of nuclear PR in P4-increased p53 expression is still unclear. Here, the molecular mechanism underlying PR-regulated p53 expression in HUVEC was investigated. Treatment with P4 increased I?B? phosphorylation and NF?-B nuclear translocation. Interestingly, P4 also increased PR-A, but not PR-B, nuclear translocation in HUVEC. Immunoprecipitation assay illustrated that P4 increased the formation of PR-A-NF?-B complex in both the cytosol and the nucleus of HUVEC. Chromatin immunoprecipitation assay showed an interaction between PR and the NF?-B binding mortif on the p53 promoter. Ablation of the NF?-B binding motif in the p53 promoter completely abolished P4-increased the p53 promoter activity. In the absence of P4, overexpression of NF?-B did not increase NF?-B nuclear translocation. In contrast, treatment of NF?-B overexpressing HUVEC with P4 for only 4 h, which is much shorter than the time (21.5 h) required for P4-induced I?B? phosphorylation, increased NF?-B nuclear translocation. Blockade of PR activity abolished this effect. Taken together, these results uncover a novel role of PR for P4-induced NF?-B nuclear translocation and suggest that PR-A-NF?-B complex formation is required for NF?-B nuclear translocation and binding onto the p53 promoter in HUVEC. Our data indicate that both nuclear and extra-nuclear signaling pathways of PR are involved in P4-regulated p53 expression in HUVEC.
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CHADS2 Score and Risk of New-onset Peripheral Arterial Occlusive Disease in Patients without Atrial Fibrillation: A Nationwide Cohort Study in Taiwan.
J. Atheroscler. Thromb.
PUBLISHED: 10-25-2014
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Aim: Although our recent cross-sectional study demonstrated that the CHADS2 score is associated with an ankle-brachial index of ?0.9 in patients without atrial fibrillation (AF), the true cause-effect relationship between these parameters remains to be evaluated. Hence, the aim of this study was to investigate whether the CHADS2 score is a useful predictor of new-onset PAOD in non-AF patients.Methods: From January 1, 2000 to December 31, 2001, a total of 723,750 patients older than 18years of age with no past history of PAOD, rheumatic heart disease or AF were surveyed from the "National Health Insurance Research Database." The CHADS2 score was calculated for each patient. Finally, 581,997 (score 0), 84,971 (score 1), 31,473 (score 2), 14,432 (score 3), 8,156 (score 4), 2,430 (score 5) and 291 (score 6) patients were studied and followed for the onset of PAOD. We further divided the study patients into four groups: group 1 (score 0), group 2 (score 1-2), group 3 (score 3-4) and group 4 (score 5-6). Results: During the follow-up period of 9.83±0.01 years, 24,775 (3.4%) patients experienced new-onset PAOD. The overall incidence of PAOD was 0.6 per 1,000 patient-years. The rate of PAOD increased from 1.8% (group 1) to 18.7% (group 4) (p?0.001). According to a multivariate analysis, groups 2-4 were significantly associated with new-onset PAOD (all p?0.001). In addition, the hazard ratio of each two-point increment in the CHADS2 score for predicting PAOD was 2.51 (p?0.001). Conclusions: The CHADS2 score is a useful predictor of new-onset PAOD in non-AF patients.
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Impact of hospital volume on long-term survival after resection for oesophageal cancer: a population-based study in Taiwan†.
Eur J Cardiothorac Surg
PUBLISHED: 10-03-2014
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Previous studies have shown that patients who undergo oesophageal cancer surgery in high-volume hospitals have lower postoperative mortality rates. However, the impact of hospital volume on long-term survival is controversial.
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Hydraulic and hemodynamic performance of a minimally invasive intra-arterial right ventricular assist device.
Int J Artif Organs
PUBLISHED: 10-02-2014
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Right ventricular assistance is still in the early phase of development compared to left ventricular assist device (LVAD) technology. In order to provide flexible pulmonary support and potentially reduce the known complications, we propose a minimally invasive right ventricular assist device (MIRVAD), located in the pulmonary artery (PA) and operating in series with the right ventricle (RV).The MIRVAD is an intra-arterial rotary blood pump containing a single axial impeller, which is not enclosed by a rigid housing but stent-fixed within the vessel. The impeller geometry has been designed with the assistance of analytical methods and computational fluid dynamics (CFD). The hydraulic performance of the impeller was evaluated experimentally with a customized test setup using blood synthetic medium (HES). The blade-tip clearance (BTC) was varied between 0.25-4.25 mm to evaluate the effect of different PA sizes on impeller performance. Furthermore, the Langrangian particle-tracking method was used to estimate the level of hemolysis and generate numerical blood damage indexes.The impeller design generated 25.6 mmHg for flow rates of 5 lpm at a speed of 6,000 rpm at the baseline condition, capable of providing sufficient support for the RV. The BTC presented a significant effect on the static pressure generation and the efficiency, but the operational range is suitable for most vessel sizes. The numerical results demonstrated a low risk of blood damage at the design point (mean Lagrangian damage index 2.6 * 10-7). The preliminary results have encouraged further impeller optimization and development of the MIRVAD.
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Evaluation of Prognostic Integrin ?2?1 PET Tracer and Concurrent Targeting Delivery Using Focused Ultrasound for Brain Glioma Detection.
Mol. Pharm.
PUBLISHED: 08-25-2014
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The ability to early detect and assess the treatment response of recurrent and/or disseminated metastatic glioblastoma is critical for the effective management of this group of patients. Accumulating experimental evidence indicates that integrin ?2?1 might be a prognostic biomarker for advanced phenotype of cancers. In this study, a novel (68)Ga-labeled integrin ?2?1-targeted PET tracer (68)Ga-NOTA-PEG4-cyclo (GDGEAyK) ((68)Ga-A2B1) was designed and evaluated for the potential prognostic imaging of glioblastoma tumor in preclinical model. To prospectively verify the prognostic value of integrin ?2?1, the in vitro Western blot and flow cytometry studies were performed to validate the integrin expression level of human glioblastoma (U87MG) cells. Extremely high expression level of integrin ?2?1 justifies its role as a potential targeting marker. Thus, (68)Ga-A2B1 positron emission tomography was performed in subcutaneous U87MG tumor bearing athymic mice at 15 min postinjection after injection of 7-8MBq tracers. The receptor targeting specificity was confirmed in a competition blocking experiment. The tumor uptake of (68)Ga-A2B1 in the control and blockage groups was 1.57 ± 0.13 %ID/g (n = 3) and 0.96 ± 0.23 %ID/g** (n = 3), respectively. However, because of the quick renal washout rate and labile nature of peptide tracers in circulation conditions, the focus ultrasound (FUS) mediated delivery method was adopted to enhance tumor uptake and retention of tracers. To test the FUS delivery efficacy in vivo, three experimental arms were designed as follows: tumor bearing mice were administrated with (68)Ga-A2B1 only or microbubbles (MBs) with FUS treatment ((68)Ga-A2B1 + FUS + MBs) or embedded (68)Ga-A2B1-microbubbles ((68)Ga-A2B1-MBs + FUS) followed with FUS sonication. The average radioactivity accumulation within a tumor was quantified from the multiple region of interest volumes using the %ID/g value and was analyzed in accordance with the ex vivo autoradiographic and pathologic data. The significant tumor uptake in (68)Ga-A2B1 + FUS +MBs group (n = 6) and (68)Ga-A2B1-MBs + FUS group (n = 4) following FUS treatment were calculated as 2.25 ± 0.50 %ID/g* and 2.6 ± 0.49 %ID/g**, comparing with (68)Ga-A2B1 only group 1.48 ± 0.42 %ID/g (n = 10). These results suggest that there is significant difference in (68)Ga-A2B1 tumor uptake by FUS treatment either with or without tracer integration with microbubbles, which demonstrate a promising delivery strategy and critical multimodal setting for phenotyping imaging of aggressive glioma tumor. In conclusion, (68)Ga labeled (68)Ga-A2B1 allows noninvasive imaging of tumor-associated ?2?1 expression and can be embedded in MB lipid shell for enhanced delivery and controlled release by sonoporation.
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Myocardial performance index derived from pre-ejection period as a novel and useful predictor of cardiovascular events in atrial fibrillation.
J Cardiol
PUBLISHED: 08-22-2014
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The pre-ejection period-derived myocardial performance index measured from tissue Doppler echocardiography (PEPa-derived MPI) was reported to be associated with left ventricular systolic and diastolic function in atrial fibrillation (AF). However, its relationship with cardiovascular outcomes in AF has never been evaluated. This study sought to examine the ability of PEPa-derived MPI in predicting adverse cardiovascular events in AF patients.
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Colchicine suppresses atrial fibrillation in failing heart.
Int. J. Cardiol.
PUBLISHED: 08-17-2014
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This study aimed to investigate the mechanism by which colchicine suppresses atrial fibrillation (AF) in a rabbit heart failure (HF) model.
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R2CHADS2 score is significantly associated with ankle-brachial index <0.9 in patients without atrial fibrillation.
Atherosclerosis
PUBLISHED: 08-01-2014
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Previous studies demonstrated CHADS2 score and impaired renal function were both associated with ankle-brachial index (ABI) < 0.9 in patients without atrial fibrillation (AF). Hence, we hypothesized the R2CHADS2 score had a significant correlation with ABI < 0.9 and the aim of this study was to validate this association in non-AF patients.
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Sputtering deposition of P-type SnO films with SnO? target in hydrogen-containing atmosphere.
ACS Appl Mater Interfaces
PUBLISHED: 07-18-2014
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In this work, we had investigated sputtering deposition of p-type SnO using the widely used and robust SnO2 target in a hydrogen-containing reducing atmosphere. The effects of the hydrogen-containing sputtering gas on structures, compositions, optical, and electrical properties of deposited SnOx films were studied. Results show that polycrystalline and SnO-dominant films could be readily obtained by carefully controlling the hydrogen gas ratio in the sputtering gas and the extent of reduction reaction. P-type conductivity was unambiguously observed for SnO-dominant films with traceable Sn components, exhibiting a p-type Hall mobility of up to ?3 cm(2) V(-1) s(-1). P-type SnO thin-film transistors using such SnO-dominant films were also demonstrated.
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Electrolessly deposited electrospun metal nanowire transparent electrodes.
J. Am. Chem. Soc.
PUBLISHED: 07-17-2014
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Metal nanowire (MNW) transparent electrodes have been widely developed for their promising sheet resistance (R(s))-transmittance (T) performance, excellent mechanical flexibility, and facile synthesis. How to lower the junction resistance without compromising optical transmittance has become the key issue in enhancing their performance. Here we combine electrospinning and electroless deposition to synthesize interconnected, ultralong MNW networks. For both silver and copper nanowire networks, the R(s) and T values reach around 10 ?/sq and 90%, respectively. This process is scalable and takes place at ambient temperature and pressure, which opens new opportunities for flexible electronics and roll-to-roll large-scale manufacturing.
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Comparison of the microbial communities in solid-state anaerobic digestion (SS-AD) reactors operated at mesophilic and thermophilic temperatures.
Appl. Microbiol. Biotechnol.
PUBLISHED: 07-08-2014
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The microbiomes involved in liquid anaerobic digestion process have been investigated extensively, but the microbiomes underpinning solid-state anaerobic digestion (SS-AD) are poorly understood. In this study, microbiome composition and temporal succession in batch SS-AD reactors, operated at mesophilic or thermophilic temperatures, were investigated using Illumina sequencing of 16S rRNA gene amplicons. A greater microbial richness and evenness were found in the mesophilic than in the thermophilic SS-AD reactors. Firmicutes accounted for 60 and 82 % of the total Bacteria in the mesophilic and in the thermophilic SS-AD reactors, respectively. The genus Methanothermobacter dominated the Archaea in the thermophilic SS-AD reactors, while Methanoculleus predominated in the mesophilic SS-AD reactors. Interestingly, the data suggest syntrophic acetate oxidation coupled with hydrogenotrophic methanogenesis as an important pathway for biogas production during the thermophilic SS-AD. Canonical correspondence analysis (CCA) showed that temperature was the most influential factor in shaping the microbiomes in the SS-AD reactors. Thermotogae showed strong positive correlation with operation temperature, while Fibrobacteres, Lentisphaerae, Spirochaetes, and Tenericutes were positively correlated with daily biogas yield. This study provided new insight into the microbiome that drives SS-AD process, and the findings may help advance understanding of the microbiome in SS-AD reactors and the design and operation of SS-AD systems.
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Chylothorax complicating video-assisted thoracoscopic surgery for non-small cell lung cancer.
World J Surg
PUBLISHED: 07-04-2014
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Chylothorax is an infrequent but well-known complication in lung cancer surgery. Previous published studies on this topic are limited, and thoracotomy has been the main surgical approach for treatment. However, chylothorax after lung cancer surgery performed solely by video-assisted thoracoscopic surgery (VATS) has rarely been investigated. The purpose of this study is to evaluate chylothorax after VATS for lung cancer.
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Two-dimensional layered transition metal disulphides for effective encapsulation of high-capacity lithium sulphide cathodes.
Nat Commun
PUBLISHED: 06-18-2014
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Fully lithiated lithium sulphide (Li2S) is currently being explored as a promising cathode material for emerging energy storage applications. Like their sulphur counterparts, Li2S cathodes require effective encapsulation to reduce the dissolution of intermediate lithium polysulphide (Li2Sn, n=4-8) species into the electrolyte. Here we report, the encapsulation of Li2S cathodes using two-dimensional layered transition metal disulphides that possess a combination of high conductivity and strong binding with Li2S/Li2Sn species. In particular, using titanium disulphide as an encapsulation material, we demonstrate a high specific capacity of 503?mAh?g(-1)(Li2S) under high C-rate conditions (4C) as well as high areal capacity of 3.0?mAh?cm(-2) under high mass-loading conditions (5.3?mg(Li2S)?cm(-2)). This work opens up the new prospect of using transition metal disulphides instead of conventional carbon-based materials for effective encapsulation of high-capacity electrode materials.
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Downregulation of Sirt1 as aging change in advanced heart failure.
J. Biomed. Sci.
PUBLISHED: 05-21-2014
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In congestive heart failure the balance between cell death and cell survival in cardiomyocytes is compromised. Sirtuin 1 (Sirt1) activates cell survival machinery and has been shown to be protective against ischemia/reperfusion injury in murine heart. The role of Sirt1 in heart failure, especially in human hearts is not clear.
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Single-Incision Versus Multiple-Incision Thoracoscopic Lobectomy and Segmentectomy: A Propensity-Matched Analysis.
Ann. Surg.
PUBLISHED: 05-20-2014
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To compare the perioperative outcomes of single-incision and multiple-incision thoracoscopic lobectomy and segmentectomy.
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Role of right upper mediastinal lymph node metastasis in patients with esophageal squamous cell carcinoma after tri-incisional esophagectomies.
Surgery
PUBLISHED: 05-12-2014
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Whereas standard (infracarinal) mediastinal lymphadenectomy refers to the clearance of lymph nodes in the middle and lower posterior mediastinum, extension along right side of trachea and upper mediastinum is termed extended lymphadenectomy. The benefit of an extended versus standard lymphadenectomy in esophageal cancer is unclear.
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The ratio of early mitral inflow velocity to global diastolic strain rate as a useful predictor of cardiac outcomes in patients with atrial fibrillation.
J Am Soc Echocardiogr
PUBLISHED: 04-24-2014
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Although the ratio of early mitral inflow velocity (E) to global diastolic strain rate (E'sr) has been correlated with left ventricular filling pressure, its relationship with cardiac outcomes in patients with atrial fibrillation (AF) has never been evaluated. The aim of this study was to examine the ability of E/E'sr ratio in predicting cardiac outcomes in patients with AF.
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Improving lithium-sulphur batteries through spatial control of sulphur species deposition on a hybrid electrode surface.
Nat Commun
PUBLISHED: 04-22-2014
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Lithium-sulphur batteries are attractive owing to their high theoretical energy density and reasonable kinetics. Despite the success of trapping soluble polysulphides in a matrix with high surface area, spatial control of solid-state sulphur and lithium sulphide species deposition as a critical aspect has not been demonstrated. Herein, we show a clear visual evidence that these solid species deposit preferentially onto tin-doped indium oxide instead of carbon during electrochemical charge/discharge of soluble polysuphides. To incorporate this concept of spatial control into more practical battery electrodes, we further prepare carbon nanofibers with tin-doped indium oxide nanoparticles decorating the surface as hybrid three-dimensional electrodes to maximize the number of deposition sites. With 12.5 ?l of 5 M Li2S8 as the catholyte and a rate of C/5, we can reach the theoretical limit of Li2S8 capacity ~\n1,470 mAh g(-1) (sulphur weight) under the loading of hybrid electrode only at 4.3 mg cm(-2).
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Selective reduction of afterload in right heart assist therapy: a mock loop study†.
Interact Cardiovasc Thorac Surg
PUBLISHED: 03-26-2014
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The treatment of right ventricular failure is closely linked to effects on pulmonary vascular resistance and thus the right ventricular (RV) afterload. Medical therapy includes afterload-decreasing drugs such as nitric oxide and prostacycline. However, current devices for mechanical unloading of the right ventricle aim at a decrease in preload increasing the pulmonary volume loading. In our concept study, we tested a minimally invasive right ventricular assist device (MIRVAD) that specifically reduces the afterload.
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Mst1 promotes cardiac myocyte apoptosis through phosphorylation and inhibition of Bcl-xL.
Mol. Cell
PUBLISHED: 03-15-2014
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The Hippo pathway, evolutionarily conserved from flies to mammals, promotes cell death and inhibits cell proliferation to regulate organ size. The core component of this cascade, Mst1 in mammalian cells, is sufficient to promote apoptosis. However, the mechanisms underlying both its activation and its ability to elicit cell death remain largely undefined. We here identify a signaling cassette in cardiac myocytes consisting of K-Ras, the scaffold RASSF1A, and Mst1 that is localized to mitochondria and promotes Mst1 activation in response to oxidative stress. Activated Mst1 phosphorylates Bcl-xL at Ser14, which resides in the BH4 domain, thereby antagonizing Bcl-xL-Bax binding. This, in turn, causes activation of Bax and subsequent mitochondria-mediated apoptotic death. Our findings demonstrate mitochondrial localization of Hippo signaling and identify Bcl-xL as a target that is directly modified to promote apoptosis.
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Evaluation of five antibiotic resistance genes in wastewater treatment systems of swine farms by real-time PCR.
Sci. Total Environ.
PUBLISHED: 03-13-2014
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Antibiotics are widely used in livestock for infection treatment and growth promotion. Wastes from animal husbandry are a potential environmental source of antibiotic-insensitive pathogens, and the removal efficiency of the resistance genotypes in current wastewater treatment plants (WWTPs) is unknown. In this study, quantitative PCR was used for evaluating antibiotic resistance genes in wastewater treatment processes. Six wastewater treatment plants in different swine farms were included in this study, and five antibiotic resistance genes (ARGs) were tested for each treatment procedure. All of the tested ARGs including tetA, tetW, sulI, sulII, and blaTEM genes were detected in six swine farms with considerable amounts. The results showed that antibiotic resistance is prevalent in livestock farming. The ARG levels were varied by wastewater treatment procedure, frequently with the highest level at anaerobic treatment tank and lowest in the activated sludge unit and the effluents. After normalizing the ARG levels to 16S rRNA gene copies, the results showed that ARGs in WWTP units fluctuated partly with the quantity of bacteria. Regardless of its importance in biodegradation, the anaerobic procedure may facilitate bacterial growth thus increasing the sustainability of the antibiotic resistance genotypes. After comparing the copy numbers in influx and efflux samples, the mean removal efficiency of ARGs ranged between 33.30 and 97.56%. The results suggested that treatments in the WWTP could partially reduce the spread of antibiotic-resistant bacteria, and additional procedures such as sedimentation may not critically affect the removal efficiency.
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Emergency endovascular aortic repair of a ruptured mycotic aorto-iliac aneurysm presenting with lumbar radiculopathy.
Cardiovasc J Afr
PUBLISHED: 03-09-2014
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Ruptured abdominal aortic aneurysm is life-threatening without immediate management. The initial clinical presentation is non-specific and impending rupture is easily missed, especially without a CT scan. We present a case of a 56-year-old man with low-back pain and left lower-extremity numbness, which was diagnosed as a herniated intervertebral disc (HIVD) with left acute sciatica syndrome. He also complained of persistent fever and abdominal discomfort. Routine blood work-up revealed leukocytosis and decreasing haemoglobin levels. CT angiography (CTA) showed impending rupture of the left aorto-iliac aneurysm. We therefore performed endovascular aneurysm repair (EVAR). Blood culture revealed Salmonella enterica, for which he received antibiotics. No acute sciatica syndrome was present immediately after the EVAR. No EVAR-related complications were noted in the one-year CTA follow up.
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Survival benefits of postoperative chemoradiation for lymph node-positive esophageal squamous cell carcinoma.
Ann. Thorac. Surg.
PUBLISHED: 03-06-2014
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Little is known about the efficacy of chemoradiation therapy after surgery for patients with esophageal squamous cell carcinoma. This retrospective study aimed to determine whether postoperative chemoradiation improves survival compared with surgery alone.
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The function of nicotinamide phosphoribosyltransferase in the heart.
DNA Repair (Amst.)
PUBLISHED: 02-12-2014
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In addition to its roles as a coenzyme and an electron transfer molecule, nicotinamide adenine dinucleotide (NAD+) has emerged as a substrate of sirtuins, a family of enzymes that control aging and metabolism. Nicotinamide phosphoribosyltransferase (Nampt), a rate-limiting enzyme in the NAD+ salvage pathway, plays an important role in controlling the level of NAD+ and the activity of Sirt1 in the heart and the cardiomyocytes therein. Nampt protects the heart from ischemia and reperfusion injury by stimulating Sirt1. In this review, we summarize what is currently known regarding the function of Nampt in the heart.
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Nickel ions from a corroded cardiovascular stent induce monocytic cell apoptosis: Proposed impact on vascular remodeling and mechanism.
J. Formos. Med. Assoc.
PUBLISHED: 02-09-2014
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Monocytes play important roles in inflammatory responses and vascular remodeling after vascular stenting. This research focused on impacts of nickel (Ni) ions released from a corroded cardiovascular stent on cytotoxicity and monocyte activation.
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Association between C-reactive protein, corrected QT interval and presence of QT prolongation in hypertensive patients.
Kaohsiung J. Med. Sci.
PUBLISHED: 02-01-2014
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C-reactive protein (CRP) and corrected QT (QTc) interval are predictors of cardiovascular disease. Whether CRP is associated with QTc interval and QT prolongation is unknown in hypertensive patients. We recruited hypertensive patients from a cardiovascular clinic in a tertiary medical center in Taiwan. All received standard 12-lead electrocardiogram examination. QT prolongation was defined as QTc interval ? 440 ms in men or ? 450 ms in women. High-sensitive CRP kits were used for the measurement of the CRP levels. A total of 466 consecutive patients were finally enrolled. Mean age was 60.6 ± 12.0 years. CRP level was correlated with QTc interval (p < 0.001) and presence of QT prolongation (p = 0.014). Multivariate regression analysis showed that CRP level (p = 0.001), age (p = 0.004), sex (p < 0.001), height (p = 0.001), low-density lipoprotein (p = 0.041), and QRS interval (p < 0.001) were associated with QTc interval. Furthermore, CRP level [odds ratio (OR) = 1.203, 95% confidence interval (CI) = 1.027-1.410, p = 0.022], age (OR = 1.040, 95% CI = 1.010-1.071, p = 0.009), waist (OR = 1.033, 95% CI = 1.000-1.066, p = 0.047), triglyceride (OR = 0.993, 95% CI = 0.987-0.999, p = 0.021) and QRS interval (OR = 1.046, 95% CI = 1.028-1.065, p < 0.001) independently predicted the presence of QT prolongation. Because CRP is an independent predictor of QTc interval and presence of QT prolongation, it could be considered in the risk assessment for hypertensive patients.
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Electrochemical tuning of layered lithium transition metal oxides for improvement of oxygen evolution reaction.
Nat Commun
PUBLISHED: 01-31-2014
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Searching for low-cost and efficient catalysts for the oxygen evolution reaction has been actively pursued owing to its importance in clean energy generation and storage. While developing new catalysts is important, tuning the electronic structure of existing catalysts over a wide electrochemical potential range can also offer a new direction. Here we demonstrate a method for electrochemical lithium tuning of catalytic materials in organic electrolyte for subsequent enhancement of the catalytic activity in aqueous solution. By continuously extracting lithium ions out of LiCoO2, a popular cathode material in lithium ion batteries, to Li0.5CoO2 in organic electrolyte, the catalytic activity is significantly improved. This enhancement is ascribed to the unique electronic structure after the delithiation process. The general efficacy of this methodology is demonstrated in several mixed metal oxides with similar improvements. The electrochemically delithiated LiCo0.33Ni0.33Fe0.33O2 exhibits a notable performance, better than the benchmark iridium/carbon catalyst.
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Spatial and temporal variations of microbial community in a mixed plug-flow loop reactor fed with dairy manure.
Microb Biotechnol
PUBLISHED: 01-23-2014
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Mixed plug-flow loop reactor (MPFLR) has been widely adopted by the US dairy farms to convert cattle manure to biogas. However, the microbiome in MPFLR digesters remains unexplored. In this study, the microbiome in a MPFLR digester operated on a mega-dairy farm was examined thrice over a 2 month period. Within 23 days of retention time, 55-70% of total manure solid was digested. Except for a few minor volatile fatty acids (VFAs), total VFA concentration and pH remained similar along the course of the digester and over time. Metagenomic analysis showed that although with some temporal variations, the bacterial community was rather stable spatially in the digester. The methanogenic community was also stable both spatially and temporally in the digester. Among methanogens, genus Methanosaeta dominated in the digester. Quantitative polymerase chain reaction (qPCR) analysis and metagenomic analysis yielded different relative abundance of individual genera of methanogens, especially for Methanobacterium, which was predominant based on qPCR analysis but undetectable by metagenomics. Collectively, the results showed that only small microbial and chemical gradients existed within the digester, and the digestion process occurred similarly throughout the MPFLR digester. The findings of this study may help improve the operation and design of this type of manure digesters.
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Tight regulation of a timed nuclear import wave of EKLF by PKC? and FOE during Pro-E to Baso-E transition.
Dev. Cell
PUBLISHED: 01-13-2014
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Erythropoiesis is a highly regulated process during which BFU-E are differentiated into RBCs through CFU-E, Pro-E, PolyCh-E, OrthoCh-E, and reticulocyte stages. Uniquely, most erythroid-specific genes are activated during the Pro-E to Baso-E transition. We show that a wave of nuclear import of the erythroid-specific transcription factor EKLF occurs during the Pro-E to Baso-E transition. We further demonstrate that this wave results from a series of finely tuned events, including timed activation of PKC?, phosphorylation of EKLF at S68 by P-PKC?(S676), and sumoylation of EKLF at K74. The latter EKLF modifications modulate its interactions with a cytoplasmic ankyrin-repeat-protein FOE and importin?1, respectively. The role of FOE in the control of EKLF nuclear import is further supported by analysis of the subcellular distribution patterns of EKLF in FOE-knockout mice. This study reveals the regulatory mechanisms of the nuclear import of EKLF, which may also be utilized in the nuclear import of other factors.
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The hOGG1 Ser326Cys gene polymorphism and the risk of coronary ectasia in the Chinese population.
Int J Mol Sci
PUBLISHED: 01-06-2014
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Oxidative stress (OS) is related to vascular inflammation possibly, contributing to the development of coronary ectasia (CE). Base excision repair (BER) and nucleotide excision repair are the main DNA repair pathways that can help to remove 8-hydroxydeoxyguanine (8-OHdG), a marker of OS. Human 8-oxoguanine DNA glycosylase 1 (hOGG1) is a key enzyme of the BER pathway and catalyzes the removal of 8-OHdG. The aim of our study was to investigate the association between hOGG1 Ser326Cys gene polymorphism and CE in a Chinese population. Five-hundred forty-seven patients who underwent diagnostic coronary angiography in a tertiary medical center were recruited. The angiographic definition of CE is the diameter of the ectatic segment being more than 1.5 times larger compared with an adjacent healthy reference segment. The gene polymorphisms were analyzed by polymerase chain reaction. The urine 8OHdG concentration was measured using a commercial ELISA kit. The distribution of hOGG1 Ser326Cys genotypes was significantly different between CE and non-CE groups (p = 0.033). The odds ratio of CE development for the Ser to the Cys variant was 1.55 (95% confidence interval (CI), 1.04-2.31, p = 0.033). Both univariate and logistic regression analysis showed a significant association of hOGG1 Ser326Cys polymorphism in the dominant model with CE development (p = 0.009 and 0.011, respectively). Urine 8-OHdG levels were significantly higher in subjects carrying the hOGG1 Ser variant than in those with the Cys/Cys genotype (p < 0.03). In conclusion, our study suggests that the hOGG1 Ser326Cys gene variant might play a role in susceptibility to the development of CE.
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Acute pulmonary injury with refractory hypoxaemia after implantation of Levitronix CentriMag ventricular assist device: successful treatment with veno-venous extracorporeal membrane oxygenation.
J Artif Organs
PUBLISHED: 01-03-2014
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Although acute pulmonary injury after cardiopulmonary bypass has been detailed in the literature, it was seldom mentioned in the context of following implantation of a ventricular assist device. We report on a 65-year-old male with end-stage ischemic cardiomyopathy who underwent implantation of Levitronix CentriMag (Levitronix, Waltham, MA) for cardiac support and was listed for heart transplantation. Acute pulmonary injury with profound hypoxaemia was noted 6 h after the implantation. Despite optimal medical treatment and maximal ventilator support, refractory hypoxaemia persisted, and veno-venous extracorporeal membrane oxygenation (oxygenator: Affinity-NT; centrifugal pump: BPX-80 Bio-Pump, Medtronic, Minneapolis, MN, USA) was applied for ventilation support. The patient was weaned from the extracorporeal membrane oxygenation 4 days later and from the ventilator on the next 2 days. He underwent a successful orthotopic heart transplant after a total of 77 days on Levitronix left ventricular device cardiac support.
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Cardiovascular events in patients with atherothrombotic disease: a population-based longitudinal study in Taiwan.
PLoS ONE
PUBLISHED: 01-01-2014
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Atherothrombotic diseases including cerebrovascular disease (CVD), coronary artery disease (CAD), and peripheral arterial disease (PAD), contribute to the major causes of death in the world. Although several studies showed the association between polyvascular disease and poor cardiovascular (CV) outcomes in Asian population, there was no large-scale study to validate this relationship in this population.
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The impact of chronic kidney disease on lipid management and goal attainment in patients with atherosclerosis diseases in Taiwan.
Int J Med Sci
PUBLISHED: 01-01-2014
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Patients with chronic kidney disease (CKD) is a very high risk cardiovascular disease population and should be treated aggressively. We investigated lipid management in CKD patients with atherosclerosis in Taiwan.
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Association of bilateral brachial-ankle pulse wave velocity difference with peripheral vascular disease and left ventricular mass index.
PLoS ONE
PUBLISHED: 01-01-2014
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Unequal arterial stiffness had been associated with cardiovascular risks. We investigated whether an association existed between unequal arterial stiffness indicated by bilateral brachial-ankle pulse wave velocity (baPWV) difference and ankle-brachial index (ABI), baPWV, echocardiographic parameters and interarm and interankle systolic blood pressure (BP) differences. A total of 1111 patients referred for echocardiographic examination were included in this study. The BPs, ABI and baPWV were measured simultaneously by an ABI-form device. The ?baPWV was defined as absolute value of difference between bilateral baPWV. We performed three multivariate analyses for determining the factors associated with a ?baPWV ? 185 cm/s (90 percentile of ?baPWV) (model 1: significant variables in univariate analysis and ABI <0.9 and baPWV; model 2: significant variables in univariate analysis and left ventricular mass index [LVMI]; model 3: significant variables in univariate analysis and interankle systolic BP difference ? 15 mmHg). The ABI <0.9 and high baPWV (both P<0.001) in model 1, high LVMI (P = 0.021) in model 2 and an interankle systolic BP difference ? 15 mmHg (P = 0.026) in model 3 were associated with a ?baPWV ? 185 cm/s, but the interarm systolic BP difference ? 10 mmHg was not (P = NS). Our study demonstrated ABI <0.9, high baPWV, high LVMI and an interankle systolic BP difference ? 15 mmHg were associated with unequal arterial stiffness.
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Coronary collateral circulation in patients of coronary ectasia with significant coronary artery disease.
PLoS ONE
PUBLISHED: 01-01-2014
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Patients with coronary ectasia (CE) usually have coexisting coronary stenosis resulting in myoischemia. Coronary collateral plays an important role in protecting myocardium from ischemia and reducing cardiovascular events. However, limited studies investigate the role of CE in coronary collaterals development.
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Associations of Pulse Pressure Index With Left Ventricular Filling Pressure and Diastolic Dysfunction in Patients With Chronic Kidney Disease.
Am. J. Hypertens.
PUBLISHED: 12-10-2013
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Patients with chronic kidney disease (CKD) often have poor vascular compliance and poor left ventricular diastolic dysfunction (LVDD). The pulse pressure index (PPI) defined as ((systolic blood pressure - diastolic blood pressure)/systolic blood pressure) reflects vascular compliance. Vascular compliance is reportedly associated with left ventricular diastolic function. This study of CKD patients investigated whether PPI correlates with the ratio of transmitral E wave velocity (E) to early diastole mitral annulus velocity (Ea) or with LVDD.
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Association between the CHADS2 Score and an Ankle-Brachial Index of ?0.9 in Patients without Atrial Fibrillation.
J. Atheroscler. Thromb.
PUBLISHED: 11-27-2013
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Aim: The ankle-brachial index(ABI) is an easy-to-use, non-invasive and reliable diagnostic tool for assessing peripheral arterial occlusive disease(PAOD). The CHADS2(congestive heart failure, hypertension, age ?75 years, diabetes, prior stroke) score is a simple and popular clinical parameter that is used to assess the risk of stroke in patients with atrial fibrillation(AF). Because all five components of the CHADS2 score are risk factors for PAOD, the score should have a strong correlation with the presence of PAOD. However, there are limited studies regarding the association between the CHADS2 score and PAOD in patients without AF. Therefore, the aim of the present study was to investigate whether the CHADS2 score is positively associated with PAOD in patients without AF. Methods: A total of 1,320 patients without AF were included in this study. The ABI was measured using an ABI-form device. PAOD was defined as an ABI of ?0.9 in either leg. Results: Among the 1,320 subjects(mean age: 60.3±13.4 years), the prevalence of an ABI of ?0.9 was 5.7%. A multivariate analysis showed that an increased age(odds ratio [OR], 1.054; p?0.001), decreased estimated glomerular filtration rate (OR, 0.971; p?0.001) and increased CHADS2 score(OR, 1.861; p?0.001) were independently associated with an ABI of ?0.9. Conclusions: Our study demonstrated that the CHADS2 score is significantly associated with an ABI of ?0.9 in non-AF patients. Further prospective studies are needed to examine the ability of the CHADS2 score to predict the incidence of PAOD.
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Predictor of poor coronary collaterals in elderly population with significant coronary artery disease.
Am. J. Med. Sci.
PUBLISHED: 11-19-2013
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Coronary collateral circulation plays an important role in protecting myocardium from ischemia and reducing cardiovascular events. Advanced age might be associated with poor coronary collateral development and cardiovascular outcome. However, limited studies investigate the predictors for collateral development in the elderly population.
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Electrochemical tuning of vertically aligned MoS2 nanofilms and its application in improving hydrogen evolution reaction.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 11-18-2013
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The ability to intercalate guest species into the van der Waals gap of 2D layered materials affords the opportunity to engineer the electronic structures for a variety of applications. Here we demonstrate the continuous tuning of layer vertically aligned MoS2 nanofilms through electrochemical intercalation of Li(+) ions. By scanning the Li intercalation potential from high to low, we have gained control of multiple important material properties in a continuous manner, including tuning the oxidation state of Mo, the transition of semiconducting 2H to metallic 1T phase, and expanding the van der Waals gap until exfoliation. Using such nanofilms after different degree of Li intercalation, we show the significant improvement of the hydrogen evolution reaction activity. A strong correlation between such tunable material properties and hydrogen evolution reaction activity is established. This work provides an intriguing and effective approach on tuning electronic structures for optimizing the catalytic activity.
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Microbial battery for efficient energy recovery.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 09-16-2013
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By harnessing the oxidative power of microorganisms, energy can be recovered from reservoirs of less-concentrated organic matter, such as marine sediment, wastewater, and waste biomass. Left unmanaged, these reservoirs can become eutrophic dead zones and sites of greenhouse gas generation. Here, we introduce a unique means of energy recovery from these reservoirs-a microbial battery (MB) consisting of an anode colonized by microorganisms and a reoxidizable solid-state cathode. The MB has a single-chamber configuration and does not contain ion-exchange membranes. Bench-scale MB prototypes were constructed from commercially available materials using glucose or domestic wastewater as electron donor and silver oxide as a coupled solid-state oxidant electrode. The MB achieved an efficiency of electrical energy conversion of 49% based on the combustion enthalpy of the organic matter consumed or 44% based on the organic matter added. Electrochemical reoxidation of the solid-state electrode decreased net efficiency to about 30%. This net efficiency of energy recovery (unoptimized) is comparable to methane fermentation with combined heat and power.
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Global left ventricular longitudinal systolic strain as a major predictor of cardiovascular events in patients with atrial fibrillation.
Heart
PUBLISHED: 09-07-2013
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Although global left ventricular longitudinal systolic strain (GLS) is a sensitive measure of left ventricular mechanics, its relationship with adverse cardiovascular (CV) events in atrial fibrillation (AF) has not been evaluated. This study sought to examine the ability of GLS in predicting CV events in AF.
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Two phloem nitrate transporters, NRT1.11 and NRT1.12, are important for redistributing xylem-borne nitrate to enhance plant growth.
Plant Physiol.
PUBLISHED: 09-04-2013
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This study of the Arabidopsis (Arabidopsis thaliana) nitrate transporters NRT1.11 and NRT1.12 reveals how the interplay between xylem and phloem transport of nitrate ensures optimal nitrate distribution in leaves for plant growth. Functional analysis in Xenopus laevis oocytes showed that both NRT1.11 and NRT1.12 are low-affinity nitrate transporters. Quantitative reverse transcription-polymerase chain reaction and immunoblot analysis showed higher expression of these two genes in larger expanded leaves. Green fluorescent protein and ?-glucuronidase reporter analyses indicated that NRT1.11 and NRT1.12 are plasma membrane transporters expressed in the companion cells of the major vein. In nrt1.11 nrt1.12 double mutants, more root-fed (15)NO3(-) was translocated to mature and larger expanded leaves but less to the youngest tissues, suggesting that NRT1.11 and NRT1.12 are required for transferring root-derived nitrate into phloem in the major veins of mature and larger expanded leaves for redistributing to the youngest tissues. Distinct from the wild type, nrt1.11 nrt1.12 double mutants show no increase of plant growth at high nitrate supply. These data suggested that NRT1.11 and NRT1.12 are involved in xylem-to-phloem transfer for redistributing nitrate into developing leaves, and such nitrate redistribution is a critical step for optimal plant growth enhanced by increasing external nitrate.
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Significant correlation of P-wave parameters with left atrial volume index and left ventricular diastolic function.
Am. J. Med. Sci.
PUBLISHED: 08-30-2013
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The 12-lead electrocardiogram (ECG) is a commonly used tool to access left atrial enlargement, which is a marker of left ventricular diastolic dysfunction (LVDD). The aim of this study was to evaluate any association of the P-wave measurements in ECG with left atrial volume (LAV) index and LVDD.
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Design Method of a Foldable Ventricular Assist Device for Minimally Invasive Implantation.
Artif Organs
PUBLISHED: 08-22-2013
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To date, ventricular assist devices (VADs) have become accepted as a therapeutic solution for end-stage heart failure patients when a donor heart is not available. Newer generation VADs allow for a significant reduction in size and an improvement in reliability. However, the invasive implantation still limits this technology to critically ill patients. Recently, expandable/deployable devices have been investigated as a potential solution for minimally invasive insertion. Such a device can be inserted percutaneously via peripheral vessels in a collapsed form and operated in an expanded form at the desired location. A common structure of such foldable pumps comprises a memory alloy skeleton covered by flexible polyurethane material. The material properties allow elastic deformation to achieve the folded position and withstand the hydrodynamic forces during operation; however, determining the optimal geometry for such a structure is a complex challenge. The numerical finite element method (FEM) is widely used and provides accurate structural analysis, but computation time is considerably high during the initial design stage where various geometries need to be examined. This article details a simplified two-dimensional analytical method to estimate the mechanical stress and deformation of memory alloy skeletons. The method was applied in design examples including two popular types of blade skeletons of a foldable VAD. Furthermore, three force distributions were simulated to evaluate the strength of the structures under different loading conditions experienced during pump operation. The results were verified with FEM simulations. The proposed two-dimensional method gives a close stress and deformation estimation compared with three-dimensional FEM simulations. The results confirm the feasibility of such a simplified analytical approach to reveal priorities for structural optimization before time-consuming FEM simulations, providing an effective tool in the initial structural design stage of foldable minimally invasive VADs.
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Association of interankle systolic blood pressure difference with peripheral vascular disease and left ventricular mass index.
Am. J. Hypertens.
PUBLISHED: 08-21-2013
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An interankle systolic blood pressure (SBP) difference has been associated with overall and cardiovascular mortality. We investigated whether an association existed between this difference and ankle-brachial index (ABI), brachial-ankle pulse wave velocity (baPWV), and echocardiographic parameters.
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Loss of CRNN expression is associated with advanced tumor stage and poor survival in patients with esophageal squamous cell carcinoma.
J. Thorac. Cardiovasc. Surg.
PUBLISHED: 06-19-2013
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CRNN gene expression is downregulated in esophageal squamous cell carcinoma (ESCC), although its clinical implications in esophageal cancer remain unclear.
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Comparison of survival among neoadjuvant chemoradiation responders, non-responders and patients receiving primary resection for locally advanced oesophageal squamous cell carcinoma: does neoadjuvant chemoradiation benefit all?
Interact Cardiovasc Thorac Surg
PUBLISHED: 05-31-2013
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While neoadjuvant chemoradiation followed by surgery has been shown to improve the survival of patients with locally advanced oesophageal cancer, it is not known whether neoadjuvant chemoradiation has a beneficial or harmful effect on the non-responders. We aimed to compare the outcomes among neoadjuvant chemoradiation responders, non-responders and patients receiving primary oesophagectomies for resectable locally advanced oesophageal squamous cell carcinoma.
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Purification and characterization of a phospholipase by Photobacterium damselae subsp. piscicida from cobia Rachycentron canadum.
J. Basic Microbiol.
PUBLISHED: 05-18-2013
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Toxicity of the extracellular products (ECPs) and the lethal attributes of phospholipase secreted by pathogenic Photobacterium damselae subsp. piscicida from cobia Rachycentron canadum was studied. An extracellular lethal toxin in the ECPs was partially purified by using Fast Protein Liquid Chromatography system. A protein band (27?kDa) exhibited phospholipase activity on Native-PAGE (by 0.3% egg yolk agar-overlay), was excised and eluted. The pI value of the purified phospholipase was determined as 3.65 and was determined as a phospholipase C by using the Amplex™ Red phosphatidylcholine -Specific phospholipase C Assay kit. The phospholipase showed maximum activity at temperature around 4-40?°C and maximal activity at pH between 8 and 9. The enzyme was inhibited by ethylenediamine-tetraacetic acid (EDTA) and sodium dodecyl sulfate (SDS); but was activated by Ca(2+) and Mg(2+) and inactivated by Zn(2+) and Cu(2+) . Both the ECPs and phospholipase were hemolytic against erythrocytes of cobia and lethal to the fish with LD50 values of 3.25 and 0.91?µg protein?g(-1) fish, respectively. In toxicity neutralization test, the rabbit antisera against the phospholipase could neutralize the toxicity of ECPs, indicating that the phospholipase is a major extracellular toxin produced by the bacterium.
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The impact of bird-beak configuration on aortic remodeling of distal arch pathology after thoracic endovascular aortic repair with the Zenith Pro-Form TX2 thoracic endograft.
J. Vasc. Surg.
PUBLISHED: 05-03-2013
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Structural changes and incomplete endograft apposition to the aortic arch (bird-beak configuration) after thoracic endovascular aortic repair are poorly understood. The aim of this study was to analyze the morphologic changes, conformability, and angulation factors in patients who underwent stainless steel-based stent graft repair of thoracic aortic pathology.
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Experimental and analytical performance evaluation of short circular hydrodynamic journal bearings used in rotary blood pumps.
Artif Organs
PUBLISHED: 05-02-2013
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Rotary blood pumps (RBPs) have demonstrated considerable promise while treating heart failure patients, such that they are being placed at an earlier stage of the disease. These devices may therefore be required to operate for prolonged durations which yields the need for RBPs exhibiting high durability, reliability, and blood compatibility. Noncontacting bearings, utilizing magnetic and/or hydrodynamic suspension techniques, appear to provide a suitable solution to these challenges. Hydrodynamic suspension has the advantage that it does not need feedback control systems. Among various hydrodynamic bearing types, the circular journal bearing has the particular benefit of easy manufacturing. This study presents methods to evaluate the performance of short (length to diameter ratio <1) circular hydrodynamic journal bearings (HJBs) for RBPs. Analytical calculations with specific boundary conditions are presented to predict the rotors eccentricity under equilibrium states and thus the related performance parameters such as load capacity, power loss, and shear rates. These results and boundary conditions were confirmed experimentally in a specially designed test set-up. The bearing performance was found to correlate to analytical solutions using the full Sommerfeld boundary condition instead of the half Sommerfeld condition conventionally used for such applications. Geometrical and operational parameter variations showed that HJB designs with a short Sommerfeld Number SS >0.02 can provide sufficient fluid film thicknesses and low shear rates. The measurements were further used to evaluate the bearings stability. The estimation of the stability threshold drawn in relation to a modified stability index and the equilibrium eccentricity of the rotor allows the prediction of stability for short circular HJB designs under full Sommerfeld condition.
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Surgical outcomes in lung cancer presenting as ground-glass opacities of 3 cm or less: A review of 5 years experience.
J Chin Med Assoc
PUBLISHED: 04-25-2013
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High-resolution computed tomography (HRCT) has become increasingly popular recently and more pulmonary ground-glass opacities (GGOs) are being identified. However, the treatment for these GGOs remains controversial. The purpose of this study was to retrospectively review the clinical and pathological characteristics and to demonstrate the longterm surgical outcomes in patients undergoing resection for GGOs in our institute.
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Performance enhancement of metal nanowire transparent conducting electrodes by mesoscale metal wires.
Nat Commun
PUBLISHED: 04-23-2013
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For transparent conducting electrodes in optoelectronic devices, electrical sheet resistance and optical transmittance are two of the main criteria. Recently, metal nanowires have been demonstrated to be a promising type of transparent conducting electrode because of low sheet resistance and high transmittance. Here we incorporate a mesoscale metal wire (1-5??m in diameter) into metal nanowire transparent conducting electrodes and demonstrate at least a one order of magnitude reduction in sheet resistance at a given transmittance. We realize experimentally a hybrid of mesoscale and nanoscale metal nanowires with high performance, including a sheet resistance of 0.36???sq(-1) and transmittance of 92%. In addition, the mesoscale metal wires are applied to a wide range of transparent conducting electrodes including conducting polymers and oxides with improvement up to several orders of magnitude. The metal mesowires can be synthesized by electrospinning methods and their general applicability opens up opportunities for many transparent conducting electrode applications.
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Endovascular stenting for nutcracker syndrome.
J Chin Med Assoc
PUBLISHED: 04-18-2013
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Nutcracker syndrome (NCS) is a rare pathology manifested by pain or hematuria in males and females alike. It can be easily overlooked, and should be considered in young men or women with symptoms of extended duration. We present a case of a 54-year-old female with chronic lower abdominal pain radiating to the left thigh of 4 years in duration. Computed tomography (CT) eventually revealed engorged left renal, gonadal, and uterine veins due to compression between the superior mesenteric artery (SMA) and the abdominal aorta, consistent with NCS. After a successful endovascular stenting and a 6-month period of antiplatelet and anticoagulant therapy, the patient returned to stable health. NCS, while rare, should be suspected in patients of both sexes with persistent pain or hematuria.
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TPX2 expression is associated with cell proliferation and patient outcome in esophageal squamous cell carcinoma.
J. Gastroenterol.
PUBLISHED: 04-17-2013
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The molecular and genetic changes underlying esophageal squamous cell carcinoma (ESCC) tumor formation and rapid progression are poorly understood. Using high-throughput data analysis, we examined molecular changes involved in ESCC pathogenesis and investigated their clinical relevance.
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Mst1 inhibits autophagy by promoting the interaction between Beclin1 and Bcl-2.
Nat. Med.
PUBLISHED: 04-12-2013
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Here we show that Mst1, a proapoptotic kinase, impairs protein quality control mechanisms in the heart through inhibition of autophagy. Stress-induced activation of Mst1 in cardiomyocytes promoted accumulation of p62 and aggresome formation, accompanied by the disappearance of autophagosomes. Mst1 phosphorylated the Thr108 residue in the BH3 domain of Beclin1, which enhanced the interaction between Beclin1 and Bcl-2 and/or Bcl-xL, stabilized the Beclin1 homodimer, inhibited the phosphatidylinositide 3-kinase activity of the Atg14L-Beclin1-Vps34 complex and suppressed autophagy. Furthermore, Mst1-induced sequestration of Bcl-2 and Bcl-xL by Beclin1 allows Bax to become active, thereby stimulating apoptosis. Mst1 promoted cardiac dysfunction in mice subjected to myocardial infarction by inhibiting autophagy, associated with increased levels of Thr108-phosphorylated Beclin1. Moreover, dilated cardiomyopathy in humans was associated with increased levels of Thr108-phosphorylated Beclin1 and signs of autophagic suppression. These results suggest that Mst1 coordinately regulates autophagy and apoptosis by phosphorylating Beclin1 and consequently modulating a three-way interaction among Bcl-2 proteins, Beclin1 and Bax.
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A transparent electrode based on a metal nanotrough network.
Nat Nanotechnol
PUBLISHED: 04-11-2013
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Transparent conducting electrodes are essential components for numerous flexible optoelectronic devices, including touch screens and interactive electronics. Thin films of indium tin oxide-the prototypical transparent electrode material-demonstrate excellent electronic performances, but film brittleness, low infrared transmittance and low abundance limit suitability for certain industrial applications. Alternatives to indium tin oxide have recently been reported and include conducting polymers, carbon nanotubes and graphene. However, although flexibility is greatly improved, the optoelectronic performance of these carbon-based materials is limited by low conductivity. Other examples include metal nanowire-based electrodes, which can achieve sheet resistances of less than 10? ?(-1) at 90% transmission because of the high conductivity of the metals. To achieve these performances, however, metal nanowires must be defect-free, have conductivities close to their values in bulk, be as long as possible to minimize the number of wire-to-wire junctions, and exhibit small junction resistance. Here, we present a facile fabrication process that allows us to satisfy all these requirements and fabricate a new kind of transparent conducting electrode that exhibits both superior optoelectronic performances (sheet resistance of ~2? ?(-1) at 90% transmission) and remarkable mechanical flexibility under both stretching and bending stresses. The electrode is composed of a free-standing metallic nanotrough network and is produced with a process involving electrospinning and metal deposition. We demonstrate the practical suitability of our transparent conducting electrode by fabricating a flexible touch-screen device and a transparent conducting tape.
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Diverse Hap43-independent functions of the Candida albicans CCAAT-binding complex.
Eukaryotic Cell
PUBLISHED: 03-29-2013
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The CCAAT motif is ubiquitous in promoters of eukaryotic genomes. The CCAAT-binding complex (CBC) is conserved across a wide range of organisms, specifically recognizes the CCAAT motif, and modulates transcription directly or in cooperation with other transcription factors. In Candida albicans, CBC is known to interact with the repressor Hap43 to negatively regulate iron utilization genes in response to iron deprivation. However, the extent of additional functions of CBC is unclear. In this study, we explored new roles of CBC in C. albicans and found that CBC pleiotropically regulates many virulence traits in vitro, including negative control of genes responsible for ribosome biogenesis and translation and positive regulation of low-nitrogen-induced filamentation. In addition, C. albicans CBC is involved in utilization of host proteins as nitrogen sources and in repression of cellular flocculation and adhesin gene expression. Moreover, our epistasis analyses suggest that CBC acts as a downstream effector of Rhb1-TOR signaling and controls low-nitrogen-induced filamentation via the Mep2-Ras1-protein kinase A (PKA)/mitogen-activated protein kinase (MAPK) pathway. Importantly, the phenotypes identified here are all independent of Hap43. Finally, deletion of genes encoding CBC components slightly attenuated C. albicans virulence in both zebrafish and murine models of infection. Our results thus highlight new roles of C. albicans CBC in regulating multiple virulence traits in response to environmental perturbations and, finally, suggest potential targets for antifungal therapies as well as extending our understanding of the pathogenesis of other fungal pathogens.
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Multiscale cross-approximate entropy analysis as a measure of complexity among the aged and diabetic.
Comput Math Methods Med
PUBLISHED: 03-22-2013
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Complex fluctuations within physiological signals can be used to evaluate the health of the human body. This study recruited four groups of subjects: young healthy subjects (Group 1, n = 32), healthy upper middle-aged subjects (Group 2, n = 36), subjects with well-controlled type 2 diabetes (Group 3, n = 31), and subjects with poorly controlled type 2 diabetes (Group 4, n = 24). Data acquisition for each participant lasted 30 minutes. We obtained data related to consecutive time series with R-R interval (RRI) and pulse transit time (PTT). Using multiscale cross-approximate entropy (MCE), we quantified the complexity between the two series and thereby differentiated the influence of age and diabetes on the complexity of physiological signals. This study used MCE in the quantification of complexity between RRI and PTT time series. We observed changes in the influences of age and disease on the coupling effects between the heart and blood vessels in the cardiovascular system, which reduced the complexity between RRI and PTT series.
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Assessment of autonomic dysfunction in patients with type 2 diabetes using reactive hyperemia.
J. Theor. Biol.
PUBLISHED: 03-13-2013
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It is known that aging and type 2 diabetes mellitus contribute to atherosclerosis and autonomic dysfunction. By using the air pressure sensing system (APSS), peak-peak intervals (PPIs) of wrist arterial waveforms from baseline and reactive hyperemia (RH) were obtained. Through frequency domain analysis of heart rate variability (HRV) and nonlinear Poincaré method, the HRV of healthy young individuals (Group 1, n=25), healthy upper middle-aged individuals (Group 2, n=22), and patients with type 2 diabetes (Group 3, n=28) were assessed. By using the standard deviation (SD) of the instantaneous PPI variability (SD1)/the SD of the long PPI variability (SD2) ratio (SSR), PPIs of the same individuals before and after RH induction were compared. Reduced SSR???? was noted only in patients with diabetes. Moreover, a significient correlation between SSR???? and endothelial function was observed in all subjects (r=0.290, p=0.033) after RH. However, no correlation with low-frequency to high-frequency power ratio (LHR) was noted before and after RH. In conclusion, according to our results, campared to the baseline, there were more significant changes of SSR???? after RH in patients with diabetes; and, a significient correlation between SSR???? and endothelial function at the moment of RH was noted.
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Influence of high-density lipoprotein cholesterol on coronary collateral formation in a population with significant coronary artery disease.
BMC Res Notes
PUBLISHED: 03-13-2013
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Coronary collateral circulation plays an important role in protecting myocardium from ischemia and reducing cardiovascular events. Low High-density lipoprotein cholesterol (HDL-C) level is a strong risk factor for coronary artery disease (CAD) and is associated with poor cardiovascular outcome. It was recently reported to be associated with poor coronary collateral development in Turkish population. Hence, we investigated the influence of HDL-C on coronary collateral formation in Chinese population.
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Non-invasive synergistic treatment of brain tumors by targeted chemotherapeutic delivery and amplified focused ultrasound-hyperthermia using magnetic nanographene oxide.
Adv. Mater. Weinheim
PUBLISHED: 03-07-2013
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The combination of chemo-thermal therapy is the best strategy to ablate tumors, but how to heat deep tumor tissues effectively without side-damage is a challenge. Here, a systemically delivered nanocarrier is designed with multiple advantages, including superior heat absorption, highly efficient hyperthermia, high drug capacity, specific targeting ability, and molecular imaging, to achieve both high antitumor efficacy and effective amplification of hyperthermia with minimal side effects.
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Clinical characteristics and risk factors for mortality in cefepime-resistant Pseudomonas aeruginosa bacteremia.
J Microbiol Immunol Infect
PUBLISHED: 02-25-2013
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To identify the clinical characteristics and risk factors for mortality of patients with cefepime-resistant Pseudomonas aeruginosa (FRPa) bacteremia.
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Clinical significance and outcomes of Clostridium perfringens bacteremia--a 10-year experience at a tertiary care hospital.
Int. J. Infect. Dis.
PUBLISHED: 02-19-2013
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The mortality rate of patients with Clostridium perfringens bacteremia is 27-44%. Typically, the clinical characteristics of this infection are non-specific, which leads to considerable difficulty with the diagnosis and early initiation of appropriate therapy.
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Heat shock protein inducer modifies arrhythmogenic substrate and inhibits atrial fibrillation in the failing heart.
Int. J. Cardiol.
PUBLISHED: 02-07-2013
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Geranylgeranylacetone (GGA) has been reported up-regulating heat shock protein (HSP) expression, and protecting against atrial remodeling. This study aimed to investigate the effects of GGA on atrial electrophysiology and inducibility of atrial fibrillation (AF) in heart failure (HF) model.
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Impact of Chronic Kidney Disease in Early Invasive versus Early Conservative Revascularization Strategies in Non-ST-Segment Elevation Acute Coronary Syndromes: A Population-Based Study from NHIRD of Taiwan.
Nephron Clin Pract
PUBLISHED: 02-05-2013
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Background: Patients with chronic kidney disease (CKD) sustaining a non-ST-segment elevation acute coronary syndrome (NSTE-ACS) are considered high risk and an early invasive strategy (EIS) is often recommended. However, the impact of CKD on patients receiving an EIS or an early conservative strategy (ECS) is unclear in real-world practice. Methods: Data were analyzed from the 2005-2008 National Health Insurance Research Database (NHIRD) in Taiwan. The diagnosis of CKD was based on the International Classification of Disease-9 codes recorded by physicians. EIS was defined as coronary angiography with intent to revascularization performed within 72 h of symptom onset. The primary endpoint was time to first major adverse cardiac event (MACE) comprising cardiovascular death, myocardial infarction (MI) and stroke. The secondary endpoints included major bleeding (MB), heart failure (HF) and dialysis during admission (DDA). Results: 834 patients (466 EIS and 368 ECS) were enrolled and age was 64.3 ± 12.6 years. Mean follow-up time was 1,163.96 ± 19.99 days. In the whole population an EIS was associated with a reduction in MACE (HR 0.69; 95% CI 0.50-0.95, p = 0.024) but not in the CKD population (HR 1.08; 95% CI 0.66-1.78, p = 0.76). Kaplan-Meier curves showed CKD subjects receiving an EIS had the highest MACE, HF and DDA rate (all p < 0.019) and CKD subjects receiving an ECS had the highest MB rate (p = 0.018). Cox regression analysis showed CKD predicted higher HF and DDA in those receiving an EIS and higher DDA and MB in those receiving an ECS. Conclusion: An EIS reduced MACE in the overall population, and CKD was a poor outcome predictor for both revascularization strategies in NSTE-ACS. © 2013 S. Karger AG, Basel.
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The prognostic value of the number of negative lymph nodes in esophageal cancer patients after transthoracic resection.
Ann. Thorac. Surg.
PUBLISHED: 02-03-2013
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Although the number of positive lymph nodes (LN), the total number of resected LN, and the proportion of positive LN have been reported to be associated with survival in patients with esophageal cancer, little is known about the prognostic impact of the number of negative LN.
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Relative contraindications for percutaneous tracheostomy: from the surgeons perspective.
Surg. Today
PUBLISHED: 01-30-2013
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Percutaneous tracheostomy (PT) has gained worldwide acceptance as a bedside procedure by intensivists, but its popularity has declined based on reports of some relative contraindications. The aim of this study was to ascertain the perioperative comorbidities of PT when it is performed by surgeons with experience performing standard tracheostomy.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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

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