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Find video protocols related to scientific articles indexed in Pubmed.
Single-molecule analysis of the self-assembly process facilitated by host-guest interactions.
Chem. Commun. (Camb.)
PUBLISHED: 11-20-2014
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The self-assembly process from a 1?:?1 to a 1?:?2 complex, facilitated by para-sulfonatocalix[6]arenes (SC6) as host and methyl viologen (MV(2+)) as guest, was analyzed at the single-molecule level through an ?-hemolysin nanopore. Especially, the assembled complex structures were discriminated in real time in the mixture of SC6 and MV(2+).
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The direct electrophilic cyanation of ?-keto esters and amides with cyano benziodoxole.
Org. Biomol. Chem.
PUBLISHED: 11-20-2014
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The direct electrophilic ?-cyanation of ?-keto esters and amides has been developed using a hypervalent iodine benziodoxole-derived cyano reagent. The procedure is accomplished within 10 min and without the use of any catalyst in DMF, at room temperature. Thus, the highly functionalized quaternary carbon-centered nitriles were produced in high to excellent yields.
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Deep localized distortion of alternating bonds and reduced transport of charged carriers in conjugated polymers under photoexcitation.
Nanoscale
PUBLISHED: 11-20-2014
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In a real bulk heterojunction polymer solar cell, after exciton separation in the heterojunction, the resulting negatively-charged carrier, a polaron, moves along the polymer chain of the acceptor, which is believed to be of significance for the charged carrier transport properties in a polymer solar cell. During the negative polaron transport, due to the external light field, the polaron, which is re-excited and induces deep localization, also forms a new local distortion of the alternating bonds. It is revealed that the excited polaron moves more slowly than the ground-state polaron. Furthermore, the velocity of the polaron moving along the polymer chain is crucially dependent on the photoexcitation. With an increase in the intensity of the optical field, the localization of the excited polaron will be deepened, with a decrease of the polaron's velocity. It is discovered that, for a charged carrier, photoexcitation is a significant factor in reducing the efficiency during the charged carrier transport in polymer solar cells. Mostly, the deep trapping effect of charged carrier in composite conjugated polymer solar cell presents an opportunity for the future application in nanoscale memory and imaging devices.
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Synthesis of a novel polyamidoamine dendrimer conjugating with alkali blue as a lymphatic tracer and study on the lymphatic targeting in vivo.
Drug Deliv
PUBLISHED: 11-20-2014
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Abstract In this study, a novel lymphatic tracer polyamidoamin-alkali blue (PAMAM-AB) was synthesized in order to evaluate the intra-lymphatic targeting ability and lymphatic tropism of PAMAM-AB after subcutaneous administration. UV-Vis, FT-IR, NMR and HPLC characterization were performed to prove the successful synthesis of PAMAM-AB. The calculated AB payload of PAMAM-AB conjugate was seven per dendrimer molecule (27.16% by weight). Hydrolysis stability of PAMAM-AB in vitro was evaluated, which was stable in PBS and human plasma. Lymphatic tracing were studied to determine the blue-stained intensity of PAMAM-AB in right popliteral lymph nodes (PLNs), iliac lymph nodes (ILNs) and para-aortic lymph nodes (PALNs) after subcutaneous administration. The pharmacokinetics and biodistribution of PAMAM-AB in mice were investigated. PLNs, ILNs and PALNs could be obviously blue-stained within 10?min after PAMAM-AB administration, and displayed a more rapid lymphatic absorption, a higher AUC value in lymph nodes and a longer lymph nodes residence time compared with methylene blue solution (MB-S), MB water-in-oil microemulsion (MB-ME), MB multiple microemulsion (MB-MME). Enhanced lymphatic drainage from the injection site and uptake into lymph of PAMAM-AB indicated that PAMAM-AB possesses the double function of lymphatic tracing and lymphatic targeting, and suggested the potential for the development of lymphatic targeting vectors or as a lymphatic tracer in its own right.
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Dynamics of syndesmophyte growth in AS as measured by quantitative CT: heterogeneity within and among vertebral disc spaces.
Rheumatology (Oxford)
PUBLISHED: 11-15-2014
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Syndesmophytes in AS typically grow slowly, but it is not known whether growth is uniform among syndesmophytes in the same intervertebral disc space (IDS) or among different IDSs in the same patient or if growth is heterogeneous. We examined the dynamics of syndesmophyte growth over 24 months using CT, with the main aim of determining if syndesmophytes in the same IDS or the same patient grow at similar rates.
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Characterization of Protein Kinase PsSRPKL, a Novel Pathogenicity Factor in the Wheat Stripe Rust Fungus.
Environ. Microbiol.
PUBLISHED: 11-10-2014
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As in other eukaryotes, protein kinases (PKs) are generally evolutionarily conserved and play major regulatory roles in plant pathogenic fungi. Many PKs have been proven to be important for pathogenesis in model fungal plant pathogens, but little is currently known about their roles in the pathogenesis of cereal rust fungi, devastating pathogens in agriculture worldwide. Here, we report on an in planta highly induced PK gene PsSRPKL from the wheat stripe rust fungus Puccinia striiformis f. sp. tritici (Pst), one of the most important cereal rust fungi. PsSRPKL belongs to a group of PKs that are evolutionarily specific to cereal rust fungi. It shows a high level of intra-species polymorphism in the kinase domains and directed GFP-chimers to plant nuclei. Overexpression of PsSRPKL in fission yeast induces aberrant cell morphology and a decreased resistance to environmental stresses. Most importantly, PsSRPKL is proven to be an important pathogenicity factor responsible for fungal growth and responses to environmental stresses, therefore contributing significantly to Pst virulence in wheat. We hypothesize that cereal rust fungi have developed specific protein kinases as pathogenicity factors for adaptation to their host species during evolution. Thus our findings provide significant insights into pathogenicity and virulence evolution in cereal rust fungi.
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Scopine as a Novel Brain-Targeting Moiety Enhances the Brain Uptake of Chlorambucil.
Bioconjug. Chem.
PUBLISHED: 11-06-2014
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The blood brain barrier (BBB) represents the biggest challenge for therapeutic drugs to enter the brain. In our study, we selected chlorambucil (CHL), an alkylating agent, as the model therapeutic agent, and used scopine as a novel brain-targeting moiety. Here, we synthesized Chlorambucil-Scopine (CHLS) prodrug and evaluated its brain-targeting efficacy. The tissue distribution study after i.v. injection revealed that the AUC0-t and Cmax of CHLS in the brain were 14.25- and 12.20-fold of CHL, respectively. Specifically, CHLS accumulated in bEnd.3 and C6 cells in an energy-dependent manner. In C6 cells, superior anti-glioma activity with a significantly decreased IC50 of 65.42 nM/mL was observed for CHLS compared to CHL (IC50 > 400 nM/mL). The safety evaluation, including acute toxicity, pathology, and hematology study, showed minimal toxicity toward nontargeting tissues, and also reached a lower systemic toxicity at 5 mg/kg (i.v.). Our results suggested that scopine is a potential brain-targeting moiety for enhancing the brain uptake efficiency of CHL.
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Sustained Effects of Sirolimus on Lung Function and Cystic Lung Lesions in Lymphangioleiomyomatosis.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 10-21-2014
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Rationale. Sirolimus therapy stabilizes lung function and reduces the size of chylous effusions and lymphangioleiomyomas in patients with lymphangioleiomyomatosis. Objectives. To determine whether sirolimus has beneficial effects on lung function, cystic areas and adjacent lung parenchyma, whether these effects are sustained, and sirolimus is well tolerated by patients. Methods. Lung function decline over time, lung volume occupied by cysts (cyst score), and lung tissue texture in the vicinity of the cysts, were quantified with a computer-aided diagnosis system, in 38 patients. Then we compared cyst scores from the last study off sirolimus with studies done on sirolimus therapy. In 12 patients, we evaluated rates of change in lung function and cyst scores off and on sirolimus. Measurements and results. Sirolimus reduced yearly declines in FEV1 (-2.3±0.1 versus 1.0±0.3 % predicted, p<0.001) and DLCO (-2.6±0.1 versus 0.9±0.2 % predicted, p<0.001). Cyst scores 1.2±0.8 years (30.5±11.9 %), and 2.5±2 years (29.7±12.1 %) after initiating sirolimus were not significantly different from pre-treatment values (28.4±12.5 %). In 12 patients, followed for five years, a significant reduction in rates of yearly decline in FEV1 (-1.4±0.2 versus 0.3±0.4 % predicted, p=0.025) was observed. Analyses of 104 computed tomography scans showed a non-significant (p=0.23) reduction in yearly rates of change of cyst scores (1.8±0.2 versus 0.3±0.3 %, p=0.23), and lung texture features. Despite adverse events, most patients were able to continue sirolimus therapy. Conclusions. Sirolimus therapy slowed down lung function decline and increase in cystic lesions. Most patients were able to tolerate sirolimus therapy.
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Targeted transplantation of human umbilical cord blood endothelial progenitor cells with immunomagnetic nanoparticles to repair corneal endothelium defect.
Stem Cells Dev.
PUBLISHED: 10-16-2014
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Corneal endothelial dysfunction involves progressive corneal edema and loss of visual acuity, which result in the need for corneal transplantation. The global shortage of donor corneas limits the development of the surgery. Reconstruction of a bioengineered corneal endothelium might resolve this problem. Various scaffolds have been used, but poor biocompatibility and degradation limit their applications. In this study, a novel method of targeted cellular transplantation without permanent residence of cell carriers in the host was proposed. Human umbilical cord blood endothelial progenitor cells (UCB EPCs) were labeled with CD34 immunomagnetic nanoparticles. The efficiency of the magnet attraction was evaluated in vitro with a simple device simulating the anterior chamber. The UCB EPCs labeled with nanoparticles were transplanted into the anterior chamber of rabbits with magnet attraction. The results indicated that labeling the nanoparticles did not affect the proliferation of the UCB EPCs. The in vitro study indicated that the magnet could directionally attract UCB EPCs labeled with nanoparticles. The in vivo study indicated that the corneas in rabbits transplanted with UCB EPCs labeled with nanoparticles and magnet attraction became relatively transparent with little edema. These results indicate that UCB EPCs labeled with CD34 immunomagnetic nanoparticles could be attracted directionally by a magnet and could repair corneal endothelial defects, providing a promising cell therapy for corneal endothelial dysfunction.
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Transmission of H7N9 influenza virus in mice by different infective routes.
Virol. J.
PUBLISHED: 10-03-2014
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On 19 February 2013, the first patient infected with a novel influenza A H7N9 virus from an avian source showed symptoms of sickness. More than 349 laboratory-confirmed cases and 109 deaths have been reported in mainland China since then. Laboratory-confirmed, human-to-human H7N9 virus transmission has not been documented between individuals having close contact; however, this transmission route could not be excluded for three families. To control the spread of the avian influenza H7N9 virus, we must better understand its pathogenesis, transmissibility, and transmission routes in mammals. Studies have shown that this particular virus is transmitted by aerosols among ferrets.
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Combinations of Oseltamivir and Fibrates Prolong the Mean Survival Time of Mice Infected with the Lethal H7N9 Influenza Virus.
J. Gen. Virol.
PUBLISHED: 10-03-2014
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The outbreak of human infections caused by the novel avian-origin H7N9 influenza viruses in China since March 2013 underscores the urgent need to find an effective treatment strategy against H7N9 infection in humans. In this study, we assessed the effectiveness of combinations of oseltamivir and two immunomodulators, simvastatin and fenofibrate, against H7N9 infection in a mouse model. Mice treated with oseltamivir plus fenofibrate exhibited the longest mean survival time, the largest reduction of viral titer in lung tissue, the highest levels of CD4+ and CD8+ T lymphocytes, and the greatest decrease in pulmonary inflammation. Thus, the combination of oseltamivir plus fenofibrate improved the outcomes of mice infected with H7N9 virus by simultaneously reducing viral replication and normalizing the aberrant immune response. This drug combination should be considered in randomized controlled trials of treatments for H7N9 patients.
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A 12-Bit High-Speed Column-Parallel Two-Step Single-Slope Analog-to-Digital Converter (ADC) for CMOS Image Sensors.
Sensors (Basel)
PUBLISHED: 09-16-2014
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A 12-bit high-speed column-parallel two-step single-slope (SS) analog-to-digital converter (ADC) for CMOS image sensors is proposed. The proposed ADC employs a single ramp voltage and multiple reference voltages, and the conversion is divided into coarse phase and fine phase to improve the conversion rate. An error calibration scheme is proposed to correct errors caused by offsets among the reference voltages. The digital-to-analog converter (DAC) used for the ramp generator is based on the split-capacitor array with an attenuation capacitor. Analysis of the DAC's linearity performance versus capacitor mismatch and parasitic capacitance is presented. A prototype 1024 × 32 Time Delay Integration (TDI) CMOS image sensor with the proposed ADC architecture has been fabricated in a standard 0.18 ?m CMOS process. The proposed ADC has average power consumption of 128 ?W and a conventional rate 6 times higher than the conventional SS ADC. A high-quality image, captured at the line rate of 15.5 k lines/s, shows that the proposed ADC is suitable for high-speed CMOS image sensors.
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Expedient Synthesis of Chiral ?-Amino Acids through Nickel-Catalyzed Reductive Cross-Coupling.
Chemistry
PUBLISHED: 09-16-2014
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A novel method for the synthesis of non-natural L- and D-amino acids by a Ni-catalyzed reductive cross-coupling reaction is described. This strategy enables the racemization-free cross-coupling of serine/homoserine- derived iodides with aryl/acyl/alkyl halides. It provides convenient access to varieties of enantiopure and functionalized amino acids, which are important building blocks in bioactive compounds and pharmaceuticals.
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Copper-catalyzed endo-type trifluoromethylarylation of alkynes.
Chem. Commun. (Camb.)
PUBLISHED: 09-13-2014
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A new copper-catalyzed trifluoromethylarylation reaction of alkynes has been developed. The transformation represents the first example of endo-type carbotrifluoromethylation of unsaturated carbon-carbon bonds and provides efficient access to a variety of CF3-substituted dihydronaphthalenes and chromenes.
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Copper-catalyzed reductive cross-coupling of nonactivated alkyl tosylates and mesylates with alkyl and aryl bromides.
Chemistry
PUBLISHED: 09-11-2014
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A copper-catalyzed reductive cross-coupling reaction of nonactivated alkyl tosylates and mesylates with alkyl and aryl bromides was developed. It provides a practical method for efficient and cost-effective construction of aryl-alkyl and alkyl-alkyl C?C bonds with stereocontrol from readily available substrates. When used in an intramolecular fashion, the reaction enables convenient access to various substituted carbo- or heterocycles, such as 2,3-dihydrobenzofuran and benzochromene derivatives.
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Subcutaneously injected ivermectin-loaded mixed micelles: formulation, pharmacokinetics and local irritation study.
Drug Deliv
PUBLISHED: 09-04-2014
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Abstract Clinical application of ivermectin (IVM) is limited by several unfavorable properties, induced by its insolubility in water. Slight differences in formulation may change the plasma pharmacokinetics and efficacy. In this study, an IVM-loaded Soy phosphatidylcholine-sodium deoxycholate mixed micelles (IVM-SPC-SDC-MMs) were developed to improve its aqueous solubility, aiming to make it more applicable for clinical use. First, IVM-SPC-SDC-MMs were prepared using the co-precipitation method. After formulation optimization, the particle size was 9.46?±?0.16?nm according to dynamic light scattering. The water solubility of IVM in SPC-SDC-MMs (4.79?±?0.02?mg/mL) was improved by 1200-fold, comparing with free IVM (0.004?mg/mL). After subcutaneous administration, the pharmacokinetic study showed that IVM-SPC-SDC-MMs and commercially available IVM injection were bioequivalent. Also, the local irritation study confirmed that IVM-SPC-SDC-MMs reduced side reactions of the commercially available IVM injection. These results indicated that IVM-SPC-SDC-MMs represented a promising new drug formulation suitable for subcutaneous delivery of IVM.
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Taichi-inspired rigid-flexible coupling cellulose-supported solid polymer electrolyte for high-performance lithium batteries.
Sci Rep
PUBLISHED: 09-03-2014
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Inspired by Taichi, we proposed rigid-flexible coupling concept and herein developed a highly promising solid polymer electrolyte comprised of poly (ethylene oxide), poly (cyano acrylate), lithium bis(oxalate)borate and robust cellulose nonwoven. Our investigation revealed that this new class solid polymer electrolyte possessed comprehensive properties in high mechanical integrity strength, sufficient ionic conductivity (3 × 10(-4) S cm(-1)) at 60°C and improved dimensional thermostability (up to 160°C). In addition, the lithium iron phosphate (LiFePO4)/lithium (Li) cell using such solid polymer electrolyte displayed superior rate capacity (up to 6 C) and stable cycle performance at 80°C. Furthermore, the LiFePO4/Li battery could also operate very well even at an elevated temperature of 160°C, thus improving enhanced safety performance of lithium batteries. The use of this solid polymer electrolyte mitigates the safety risk and widens the operation temperature range of lithium batteries. Thus, this fascinating study demonstrates a proof of concept of the use of rigid-flexible coupling solid polymer electrolyte toward practical lithium battery applications with improved reliability and safety.
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Accurate predictions of C-SO2R bond dissociation enthalpies using density functional theory methods.
Phys Chem Chem Phys
PUBLISHED: 08-29-2014
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The dissociation of the C-SO2R bond is frequently involved in organic and bio-organic reactions, and the C-SO2R bond dissociation enthalpies (BDEs) are potentially important for understanding the related mechanisms. The primary goal of the present study is to provide a reliable calculation method to predict the different C-SO2R bond dissociation enthalpies (BDEs). Comparing the accuracies of 13 different density functional theory (DFT) methods (such as B3LYP, TPSS, and M05 etc.), and different basis sets (such as 6-31G(d) and 6-311++G(2df,2p)), we found that M06-2X/6-31G(d) gives the best performance in reproducing the various C-S BDEs (and especially the C-SO2R BDEs). As an example for understanding the mechanisms with the aid of C-SO2R BDEs, some primary mechanistic studies were carried out on the chemoselective coupling (in the presence of a Cu-catalyst) or desulfinative coupling reactions (in the presence of a Pd-catalyst) between sulfinic acid salts and boryl/sulfinic acid salts.
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[Effects of postconditioning on autophagy of lung ischemic reperfusion injury in rats].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-23-2014
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To explore the effects of postconditioning on autophagy of lung injury in situ during lung ischemic reperfusion.
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Augment low-field intra-operative MRI with preoperative MRI using a hybrid non-rigid registration method.
Comput Methods Programs Biomed
PUBLISHED: 08-19-2014
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Preoperatively acquired diffusion tensor image (DTI) and blood oxygen level dependent (BOLD) have been proved to be effective in providing more anatomical and functional information; however, the brain deformation induced by brain shift and tumor resection severely impairs the correspondence between the image space and the patient space in image-guided neurosurgery.
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Aerobic Oxidation of Hydroxymethylfurfural and Furfural by Using Heterogeneous Cox Oy -N@C Catalysts.
ChemSusChem
PUBLISHED: 08-17-2014
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2,5-Furandicarboxylic acid (FDCA) is considered to be a promising replacement for terephthalic acid since they share similar structures and properties. In contrast to FDCA, 2,5-furandicarboxylic acid methyl (FDCAM) has properties that allow it to be easily purified. In this work, we reported an oxidative esterification of 5-hydroxymethylfurfural (HMF) and furfural to prepare corresponding esters over Cox Oy -N@C catalysts using O2 as benign oxidant. High yield and selectivity of FDCAM and methyl 2-furoate were obtained under optimized conditions. Factors which influenced the product distribution were examined thoroughly. The Cox Oy -N@C catalysts were recycled five times and no significant loss of activity was detected. Characterization of the catalysts could explain such phenomena. Using XPS and TGA, we made a thorough investigation of the effects of ligand and pyrolysis temperature on catalyst activity.
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Computer-aided detection of exophytic renal lesions on non-contrast CT images.
Med Image Anal
PUBLISHED: 08-15-2014
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Renal lesions are important extracolonic findings on computed tomographic colonography (CTC). They are difficult to detect on non-contrast CTC images due to low image contrast with surrounding objects. In this paper, we developed a novel computer-aided diagnosis system to detect a subset of renal lesions, exophytic lesions, by (1) exploiting efficient belief propagation to segment kidneys, (2) establishing an intrinsic manifold diffusion on kidney surface, (3) searching for potential lesion-caused protrusions with local maximum diffusion response, and (4) exploring novel shape descriptors, including multi-scale diffusion response, with machine learning to classify exophytic renal lesions. Experimental results on the validation dataset with 167 patients revealed that manifold diffusion significantly outperformed conventional shape features (p<1e-3) and resulted in 95% sensitivity with 15 false positives per patient for detecting exophytic renal lesions. Fivefold cross-validation also demonstrated that our method could stably detect exophytic renal lesions. These encouraging results demonstrated that manifold diffusion is a key means to enable accurate computer-aided diagnosis of renal lesions.
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On computing stress in polymer systems involving multi-body potentials from molecular dynamics simulation.
J Chem Phys
PUBLISHED: 08-10-2014
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Hardy stress definition has been restricted to pair potentials and embedded-atom method potentials due to the basic assumptions in the derivation of a symmetric microscopic stress tensor. Force decomposition required in the Hardy stress expression becomes obscure for multi-body potentials. In this work, we demonstrate the invariance of the Hardy stress expression for a polymer system modeled with multi-body interatomic potentials including up to four atoms interaction, by applying central force decomposition of the atomic force. The balance of momentum has been demonstrated to be valid theoretically and tested under various numerical simulation conditions. The validity of momentum conservation justifies the extension of Hardy stress expression to multi-body potential systems. Computed Hardy stress has been observed to converge to the virial stress of the system with increasing spatial averaging volume. This work provides a feasible and reliable linkage between the atomistic and continuum scales for multi-body potential systems.
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Cu-catalyzed Suzuki-Miyaura reactions of primary and secondary benzyl halides with arylboronates.
Chem. Commun. (Camb.)
PUBLISHED: 08-07-2014
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A copper-catalyzed Suzuki-Miyaura coupling of benzyl halides with arylboronates is described. Varieties of primary benzyl halides as well as more challenging secondary benzyl halides with ? hydrogens or steric hindrance could be successfully converted into the corresponding products. Thus it provides access to diarylmethanes, diarylethanes and triarylmethanes.
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Brain-specific delivery of dopamine mediated by n,n-dimethyl amino group for the treatment of Parkinson's disease.
Mol. Pharm.
PUBLISHED: 08-06-2014
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Parkinson's disease (PD) has become one of the most deadly diseases due to a lack of effective treatment. Herein, N-3,4-bis(pivaloyloxy)dopamine-3-(dimethylamino)propanamide (PDDP), a brain-specific derivative of dopamine, was designed and synthesized, which consists of a brain targeted ligand, N,N-dimethyl amino group, and two dipivaloyloxy groups for lipophilic modification. PDDP was investigated both in vitro and in vivo by comparing with L-DOPA and another derivative (BPD) without N,N-dimethyl amino group. PDDP showed a more pronounced accumulation in mouse brain microvascular endothelial cells (bEnd.3) than BPD via an active transport process. The increased cellular uptake of PDDP was proven to be mediated by putative pyrilamine cationic transporters. Following intravenous administration, the concentration of PDDP in the brain was 269.28-fold and 6.41-fold higher than that of L-DOPA and BPD at 5 min, respectively. Additionally, PDDP effectively attenuated the striatum lesion caused by 6-hydroxydopamine (6-OHDA) in rats. More importantly, PDDP presented antioxidant and antiapoptotic effects on 6-OHDA-induced toxicity in human neuroblastoma cells (SH-SY5Y). Thus, N,N-dimethyl amino group-based PDDP represents an effective and safe treatment for PD.
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Genetic variation in the tissue factor gene is associated with clinical outcome in severe sepsis patients.
Crit Care
PUBLISHED: 08-03-2014
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IntroductionActivation of inflammation and coagulation was closely related and mutually interdependent in sepsis. Tissue factor (TF) and its endogenous inhibitor, tissue factor pathway inhibitor (TFPI) was the main regulators of the initiation of coagulation process. Altered plasma levels of TF and TFPI have been related to worse outcome in sepsis. The objective of this study was to investigate whether single nucleotide polymorphisms (SNPs) in the TF and TFPI genes were associated with risk and outcome for patients with severe sepsis.MethodsSeventeen SNPs in TF and TFPI were genotyped in samples of sepsis (n =577) and severe sepsis patients (n =476), and tested for association in this case¿control collection. We then investigated correlation between the associated SNPs and the mRNA expression, and protein level of the corresponding gene. The mRNA levels of TF were determined using real-time quantitative reverse transcription-polymerase chain reaction and the soluble plasma levels of TF were measured using enzyme linked immunosorbent assay (ELISA) method.ResultsAssociation analysis revealed that three TF SNPs in perfect linkage disequilibrium, rs1361600, rs3917615 and rs958587, were significantly associated with outcome of severe sepsis. G allele frequency of rs1361600 in survivor patients was significantly higher than that in nonsurvivor severe sepsis patients (P =4.91¿×¿10¿5, odds ratio (OR) =0.48, 95% confidence interval (CI) 0.33 to 0.69). The association remained significant after adjustment for covariates in multiple logistic regression analysis and for multiple comparisons. Lipopolysaccharide-induced TF-mRNA expression levels in peripheral blood mononuclear cells from subjects carrying rs1361600 AG and GG genotypes, were significantly lower than those subjects carrying AA genotype (P =0.0012). Moreover, severe sepsis patients of GG and GA genotypes showed lower serum levels of TF than patients with AA genotype (P adj =0.02). The plasma levels of TF were also associated with outcome of severe sepsis patients (P adj =0.01). However, genotype and allele analyses did not show any significant difference between sepsis and severe sepsis patients.ConclusionsOur findings indicate that common genetic variation in TF was significantly associated with outcome of severe sepsis in Chinese Han population.
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Effects of Melatonin on the Proliferation and Apoptosis of Sheep Granulosa Cells under Thermal Stress.
Int J Mol Sci
PUBLISHED: 07-30-2014
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The cross-talk between oocyte and somatic cells plays a crucial role in the regulation of follicular development and oocyte maturation. As a result, granulosa cell apoptosis causes follicular atresia. In this study, sheep granulosa cells were cultured under thermal stress to induce apoptosis, and melatonin (MT) was examined to evaluate its potential effects on heat-induced granulosa cell injury. The results demonstrated that the Colony Forming Efficiency (CFE) of granulosa cells was significantly decreased (heat 19.70% ± 1.29% vs. control 26.96% ± 1.81%, p < 0.05) and the apoptosis rate was significantly increased (heat 56.16% ± 13.95% vs. control 22.80% ± 12.16%, p < 0.05) in granulosa cells with thermal stress compared with the control group. Melatonin (10-7 M) remarkably reduced the negative effects caused by thermal stress in the granulosa cells. This reduction was indicated by the improved CFE and decreased apoptotic rate of these cells. The beneficial effects of melatonin on thermal stressed granulosa cells were not inhibited by its membrane receptor antagonist luzindole. A mechanistic exploration indicated that melatonin (10-7 M) down-regulated p53 and up-regulated Bcl-2 and LHR gene expression of granulosa cells under thermal stress. This study provides evidence for the molecular mechanisms of the protective effects of melatonin on granulosa cells during thermal stress.
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Rifampicin Loaded Mannosylated Cationic Nanostructured Lipid Carriers for Alveolar Macrophage-specific Delivery.
Pharm. Res.
PUBLISHED: 07-11-2014
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In this study, cationic mannosylated nanostructured lipid carriers (Man-NLCs) were developed for the targeted delivery of rifampicin to alveolar macrophages.
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The timing of surgical treatment of knee dislocations: a systematic review.
Knee Surg Sports Traumatol Arthrosc
PUBLISHED: 07-04-2014
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Traumatic knee dislocations (KDs) are unusual yet limb-threatening injuries; the timing of surgical intervention is still debated. A systematic review was performed to determine the optimal timing of surgery with respect to injury pattern.
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Adenosine Triphosphate-Induced Rabbit Corneal Endothelial Cell Proliferation in vitro via the P2Y2-PI3K/Akt Signaling Axis.
Cells Tissues Organs (Print)
PUBLISHED: 07-01-2014
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Purpose: To investigate the effect of the ATP-P2Y2-PI3K/Akt signaling axis on promoting rabbit corneal endothelial cell (RCEC) proliferation in vitro. Methods: Five concentrations of adenosine triphosphate (ATP; 1, 10, 25, 50 and 100 ?M) were added to RCECs, and the cell proliferation was detected using Cell Counting Kit-8 (CCK8) and Ki67 immunohistochemical staining. Other P2Y2 receptor agonists and antagonists were added to the cells, and the proliferation effect was evaluated using CCK8 to determine the involvement of the P2Y2 receptor. Changes in the expression of phosphorylated Akt in RCECs treated with different concentrations of extracellular ATP and the duration of extracellular ATP on Akt phosphorylation were investigated using Western blotting. The pharmacological profiles with or without the PI3K/Akt pathway inhibitors were also determined using Western blotting. Results: We found that 10 ?M ATP strongly promoted RCEC proliferation in vitro. Additionally, 25 ?M ATP had a proliferation effect, whereas other concentrations (1, 50 and 100 ?M) had no effect compared with the control group. Selective P2Y2 receptor agonists (UTP, ATP?S and Ap4A) showed the same promotion effect, while P2Y2 antagonists and PI3K/Akt inhibitors inhibited the effect of ATP. Moreover, phosphorylated Akt could be induced by the addition of extracellular ATP at all five concentrations and lasted for 1 h. This phosphorylation was prevented by PI3K/Akt inhibitors and a P2Y2 antagonist. Conclusions: These findings showed that 10 ?M ATP markedly promoted RCEC proliferation via the P2Y2-PI3K/Akt signaling axis. © 2014 S. Karger AG, Basel.
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Mechanistic study of chemoselectivity in Ni-catalyzed coupling reactions between azoles and aryl carboxylates.
J. Am. Chem. Soc.
PUBLISHED: 05-27-2014
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Itami et al. recently reported the C-O electrophile-controlled chemoselectivity of Ni-catalyzed coupling reactions between azoles and esters: the decarbonylative C-H coupling product was generated with the aryl ester substrates, while C-H/C-O coupling product was generated with the phenol derivative substrates (such as phenyl pivalate). With the aid of DFT calculations (M06L/6-311+G(2d,p)-SDD//B3LYP/6-31G(d)-LANL2DZ), the present study systematically investigated the mechanism of the aforementioned chemoselective reactions. The decarbonylative C-H coupling mechanism involves oxidative addition of C(acyl)-O bond, base-promoted C-H activation of azole, CO migration, and reductive elimination steps (C-H/Decar mechanism). This mechanism is partially different from Itami's previous proposal (Decar/C-H mechanism) because the C-H activation step is unlikely to occur after the CO migration step. Meanwhile, C-H/C-O coupling reaction proceeds through oxidative addition of C(phenyl)-O bond, base-promoted C-H activation, and reductive elimination steps. It was found that the C-O electrophile significantly influences the overall energy demand of the decarbonylative C-H coupling mechanism, because the rate-determining step (i.e., CO migration) is sensitive to the steric effect of the acyl substituent. In contrast, in the C-H/C-O coupling mechanism, the release of the carboxylates occurs before the rate-determining step (i.e., base-promoted C-H activation), and thus the overall energy demand is almost independent of the acyl substituent. Accordingly, the decarbonylative C-H coupling product is favored for less-bulky group substituted C-O electrophiles (such as aryl ester), while C-H/C-O coupling product is predominant for bulky group substituted C-O electrophiles (such as phenyl pivalate).
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A photochromic supramolecular polymer based on bis-p-sulfonatocalix[4]arene recognition in aqueous solution.
Chem. Commun. (Camb.)
PUBLISHED: 05-24-2014
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A photochromic supramolecular polymer based on bis-p-sulfonatocalix[4]arene recognition with a dithienylethene derivative in aqueous solution was fabricated. The resultant polymer showed good photochromic behaviour with obvious colour switching and a morphology change under alternative UV/Vis light stimuli.
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PEGylated fluorescent carbon nanoparticles for noninvasive heart imaging.
Bioconjug. Chem.
PUBLISHED: 05-22-2014
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Fluorescent carbon nanoparticles (CNP) have gained much attention due to their unique fluorescent properties and safety. In this study, we evaluated the potential application of CNP and PEGylated CNP (PEG-CNP) in noninvasive heart imaging. CNP was prepared by hydrothermal treatment of silk. The particle size and zeta potential of CNP were 121.8 nm and -3.7 mV, respectively, which did not change significantly after PEGylation with a PEG density of 4.43 ± 0.02 ?g/mg CNP. FTIR and XPS showed that CNP possessed several functional groups, such as -COOH, -OH, and NH2, which could be utilized for PEGylation and other modifications. CNP displayed strong blue fluorescence after excitation at the wavelength of 375 nm. PEG-CNP displayed better serum stability compared to CNP. The hemolysis rate of PEG-CNP was lower than that of CNP, suggesting PEGylation could enhance the hemocompatibility of CNP. Both CNP and PEG-CNP showed higher uptake capacity by H9c2 cells (a heart cell line) than that by human umbilical vein endothelial cells (HUVEC), suggesting the particles tend to be selectively taken up by heart cells. Both CNP and PEG-CNP were proven to be taken up through endosome-mediated pathway, and the colocalization of nanoparticles with mitochondria was also observed. In vivo results demonstrated that CNP could target heart with much higher fluorescent intensity than liver and spleen. Although PEGylation could decrease the distribution in heart, it remained high for PEG-CNP. In conclusion, CNP could be used for heart imaging, and moreover, PEGylation could improve the stability and biocompatibility of CNP.
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Hydrolysis reaction mechanism in atrazine metabolism and prediction of its metabolites' toxicities.
J. Agric. Food Chem.
PUBLISHED: 05-16-2014
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Atrazine (ATR) is a widely used herbicide. There are several types of reactions in its metabolism. Herein, the mechanism of three paths of hydrolysis reactions in its metabolism and predictions of toxicities of its metabolites in the three paths will be presented. The calculation results by B3LYP (Becke, 3-parameter, Lee-Yang-Parr), one of the approaches in density functional theory, indicated that (1) there were three models in the three hydrolysis paths of ATR. The dissociation mechanisms of C(9/11)-N(8/10), C(4/6)-N(8/10), and C-Cl were dealkylation, deamination, and Cl substitution, respectively. (2) The energy barrier of C-Cl dissociation was lower. The dissociation was advantageous in dynamics and the primary reaction in the three hydrolysis paths. In these hydrolysis reactions, the different intermediates had different concentrations because of the impact of the reaction rate. (3) In addition, it was necessary to consider the solvent effect to investigate hydrolysis reaction. The conductor-like polarizable continuum model (CPCM) was used to simulate the hydrolysis reaction in bond length and energy barrier because of the solvent effect. Experimental or predictive results showed that atrazine and its metabolites in the three hydrolysis paths were carcinogenic.
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Evaluation of clinical application of ESICM acute gastrointestinal injury grading system: a single-center observational study.
Chin. Med. J.
PUBLISHED: 05-15-2014
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In 2012, the working group on abdominal problems of the European Society of Intensive Care Medicine (ESICM) proposed a definition and also guidelines for the grading system and treatment of acute gastrointestinal injury (AGI). Until now, clinical reports on this topic have not been available, and the practicality of using the AGI grading system requires further validation in the clinic. Therefore, we conducted this study to evaluate the feasibility of utilizing the current AGI grading system in a clinical environment, and to provide evidence for its usefulness in assessing the severity and prognosis of critically ill patients with gastrointestinal dysfunction.
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Worse cardiometabolic health in African immigrant men than African American men: reconsideration of the healthy immigrant effect.
Metab Syndr Relat Disord
PUBLISHED: 05-09-2014
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The healthy immigrant effect is a phrase that has been used for decades to describe better cardiometabolic health in African immigrants than African Americans. The recent global increase in cardiometabolic diseases raises the possibility that immigrant health may be changing. Therefore, a new assessment of cardiometabolic health in African immigrants is warranted.
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[Histopathological changes in EV71-infected mouse model:a transmission electron microscopic study].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 04-19-2014
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To document ultrastructural changes of brain, spinal cord, skeletal muscle, jejunum and lung of EV71 infection mouse model, and to explore the myotropism and pathogenesis of EV71 in nervous system.
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FunSeq2: A framework for prioritizing noncoding regulatory variants in cancer.
Genome Biol.
PUBLISHED: 04-17-2014
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Identification of noncoding drivers from thousands of somatic alterations in a typical tumor is a difficult and unsolved problem. We report a computational framework, FunSeq2, to annotate and prioritize these mutations. The framework combines an adjustable data context integrating large-scale genomics and cancer resources with a streamlined variant-prioritization pipeline. The pipeline has a weighted scoring system combining: inter- and intra-species conservation; loss- and gain-of function events for transcription-factor binding; enhancer-gene linkages and network centrality; and per-element recurrence across samples. We further highlight putative drivers with information specific to a particular sample, such as differential expression. FunSeq2 is available from funseq2.gersteinlab.org.
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Distribution of enterovirus 71 RNA in inflammatory cells infiltrating different tissues in fatal cases of hand, foot, and mouth disease.
Arch. Virol.
PUBLISHED: 04-16-2014
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In previous studies of hand, foot, and mouth disease patients fatally infected with enterovirus 71 (EV71), the distribution of viral protein, but not the genome, was determined. To understand the pathogenesis of EV71, however, it is important to investigate the spread of the viral genome. There have been no pathological studies of in situ EV71 viral RNA in inflammatory cells infiltrating various tissues of fatal cases. We therefore first investigated the distribution and classification of inflammatory cells in various tissues and then performed in situ EV71 RNA hybridization in these tissues to better understand the pathogenesis of EV71 infection. EV71 RNA was found mainly in inflammatory cells infiltrating the central nervous system (CNS), intestines, lungs, and tonsils. Most EV71 RNA-positive inflammatory cells in the CNS were macrophages/microglia and neutrophils infiltrating the perivascular cuffing, microglial nodule, neuronophagia, and meninges. CD68+ macrophages and CD15+ neutrophils were diffusely distributed in tissues with severe pathological changes. This study demonstrates the presence of EV71 RNA in inflammatory cells infiltrating tissues in fatally infected patients. Our findings suggest that fatal EV71 infection with extensive infiltration of macrophages/microglia and neutrophils into the CNS results in severe neurological lesions.
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An adjuvanted inactivated murine cytomegalovirus (MCMV) vaccine induces potent and long-term protective immunity against a lethal challenge with virulent MCMV.
BMC Infect. Dis.
PUBLISHED: 04-04-2014
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Human cytomegalovirus (HCMV) is a ubiquitous pathogen that causes serious problems in immunocompromised or immunologically immature hosts. Vaccination is the preferred approach for prevention of HCMV infection, but so far no approved HCMV vaccine is available. In this study, we assessed the immunogenicity and protective immunity of a formalin-inactivated murine cytomegalovirus vaccine (FI-MCMV) in a mouse model in combination with adjuvants MF59, alum, or chitosan.
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Tumor sensitive matching flow: A variational method to detecting and segmenting perihepatic and perisplenic ovarian cancer metastases on contrast-enhanced abdominal CT.
Med Image Anal
PUBLISHED: 03-31-2014
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Accurate automated segmentation and detection of ovarian cancer metastases may improve the diagnosis and prognosis of women with ovarian cancer. In this paper, we focus on an important subset of ovarian cancer metastases that spread to the surface of the liver and spleen. Automated ovarian cancer metastasis detection and segmentation are very challenging problems to solve. These metastases have a wide variety of shapes and intensity values similar to that of the liver, spleen and adjacent soft tissues. To address these challenges, this paper presents a variational approach, called tumor sensitive matching flow (TSMF), to detect and segment perihepatic and perisplenic ovarian cancer metastases. TSMF is an image motion field that only highlights metastasis-caused deformation on the surface of liver and spleen while dampening all other image motion between the patient image and the atlas image. It provides several benefits: (1) juxtaposing the roles of image matching and metastasis classification within a variational framework; (2) only requiring a small set of features from a few patient images to train a metastasis-likelihood function for classification; and (3) dynamically creating shape priors for geodesic active contour (GAC) to prevent inaccurate metastasis segmentation. We compared the TSMF to an organ surface partition (OSP) baseline approach. At a false positive rate of 2 per patient, the sensitivities of TSMF and OSP were 87% and 17% (p<0.001), respectively. In a comparison of the segmentations conducted using TSMF-constrained GAC and conventional GAC, the volume overlap rates were 73 ± 9% and 46 ± 26% (p<0.001) and average surface distances were 2.4 ± 1.2 mm and 7.0 ± 6.0 mm (p<0.001), respectively. These encouraging results demonstrate that TSMF could accurately detect and segment ovarian cancer metastases.
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Dynamic changes of tear fluid after cosmetic transcutaneous lower blepharoplasty measured by optical coherence tomography.
Am. J. Ophthalmol.
PUBLISHED: 03-27-2014
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To investigate the dynamic changes of tear fluid after cosmetic transcutaneous lower blepharoplasty.
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Feasibility of using the marginal blood vessels as reference landmarks for CT colonography.
AJR Am J Roentgenol
PUBLISHED: 02-27-2014
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The purpose of this study was to show the spatial relationship of the colonic marginal blood vessels and the teniae coli on CT colonography (CTC) and the use of the marginal blood vessels for supine-prone registration of polyps and for determination of proper connectivity of collapsed colonic segments.
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Enhancement of neighbouring-group participation in Cu0-promoted cross-coupling gem-difluoromethylenation of aryl/alkenyl halides with 1,3-azolic difluoromethyl bromides.
Chemistry
PUBLISHED: 02-15-2014
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A copper(0)-promoted direct reductive gem-difluoromethylenation of unactivated aryl or alkenyl halides with benzo-1,3-azolic (oxa-, thia- or aza-) difluoromethyl bromides or 2-bromodifluoromethyl-1,3-oxazoline has been developed for the construction of pharmaceutically important gem-difluoromethylene-linked twin molecules. The unique ?-conjugated aryl-fused 1,3-azolic moiety in difluoromethyl bromide substrates could stabilise the reaction intermediates, which promotes the reactivities, providing facile access to the cross-coupling products in good to excellent yields, and allowing significant functional group tolerance. The reaction exhibits an enhanced neighbouring-group-participation effect. This method could provide a new strategy for the construction of gem-difluoromethylene-linked identical or nonidentical twin drugs through further functionalisation of 1,3-azolic skeletons.
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Patient specific tumor growth prediction using multimodal images.
Med Image Anal
PUBLISHED: 02-11-2014
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Personalized tumor growth model is valuable in tumor staging and therapy planning. In this paper, we present a patient specific tumor growth model based on longitudinal multimodal imaging data including dual-phase CT and FDG-PET. The proposed Reaction-Advection-Diffusion model is capable of integrating cancerous cell proliferation, infiltration, metabolic rate and extracellular matrix biomechanical response. To bridge the model with multimodal imaging data, we introduce Intracellular Volume Fraction (ICVF) measured from dual-phase CT and Standardized Uptake Value (SUV) measured from FDG-PET into the model. The patient specific model parameters are estimated by fitting the model to the observation, which leads to an inverse problem formalized as a coupled Partial Differential Equations (PDE)-constrained optimization problem. The optimality system is derived and solved by the Finite Difference Method. The model was evaluated by comparing the predicted tumors with the observed tumors in terms of average surface distance (ASD), root mean square difference (RMSD) of the ICVF map, average ICVF difference (AICVFD) of tumor surface and tumor relative volume difference (RVD) on six patients with pathologically confirmed pancreatic neuroendocrine tumors. The ASD between the predicted tumor and the reference tumor was 2.4±0.5mm, the RMSD was 4.3±0.4%, the AICVFD was 2.6±0.6%, and the RVD was 7.7±1.3%.
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Rapid adaptation of avian H7N9 virus in pigs.
Virology
PUBLISHED: 01-20-2014
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How the H7N9 avian influenza virus gained the distinct ability to infect humans is unclear. Pigs are an important host in influenza virus ecology because they are susceptible to infection with both avian and human influenza viruses and are often involved in interspecies transmission. Here, we passaged one avian isolate and one human isolate in pigs to examine the mammalian host adaptation of the H7N9 virus. The avian virus replicated to a high titer after one passage, whereas the human isolate replicated poorly after three passages in pig lungs. Sequence analysis found nine substitutions in the HA, NA, M and NS segments of the avian isolate, which enhanced the binding affinity for human-type receptors. These results indicate that avian H7N9 influenza viruses can be easily adapted to pigs and that pigs may act as an important intermediate host for the reassortment and transmission of such novel viruses.
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Sustainable, heat-resistant and flame-retardant cellulose-based composite separator for high-performance lithium ion battery.
Sci Rep
PUBLISHED: 01-13-2014
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A sustainable, heat-resistant and flame-retardant cellulose-based composite nonwoven has been successfully fabricated and explored its potential application for promising separator of high-performance lithium ion battery. It was demonstrated that this flame-retardant cellulose-based composite separator possessed good flame retardancy, superior heat tolerance and proper mechanical strength. As compared to the commercialized polypropylene (PP) separator, such composite separator presented improved electrolyte uptake, better interface stability and enhanced ionic conductivity. In addition, the lithium cobalt oxide (LiCoO2)/graphite cell using this composite separator exhibited better rate capability and cycling retention than that for PP separator owing to its facile ion transport and excellent interfacial compatibility. Furthermore, the lithium iron phosphate (LiFePO4)/lithium cell with such composite separator delivered stable cycling performance and thermal dimensional stability even at an elevated temperature of 120°C. All these fascinating characteristics would boost the application of this composite separator for high-performance lithium ion battery.
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Histopathological features and distribution of EV71 antigens and SCARB2 in human fatal cases and a mouse model of enterovirus 71 infection.
Virus Res.
PUBLISHED: 01-12-2014
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Enterovirus 71 (EV71) is a neurotropic pathogen that causes hand, foot, and mouth disease. While infection is usually self-limiting, a minority of patients infected with EV71 develop severe neurological complications. In humans, EV71 has been reported to utilize the scavenger receptor class B, member 2 (SCARB2) as a receptor for infectious cellular entry. In this study, we define the pathological features of EV71-associated disease as well as the distribution of EV71 antigen and SCARB2 in human fatal cases and a mouse model. Histopathologically, human fatal cases showed severe central nervous system (CNS) changes, mainly in the brainstems, spinal cords, and thalamus. These patient further exhibited pulmonary edema and necrotic enteritis. Immunohistochemical analysis of human fatal cases demonstrated that EV71 antigen and SCARB2 were observed mainly in neurons, microglia cells and inflammatory cells in the CNS, and epithelial cells in the intestines. However, skeletal muscle tissue was negative for EV71 antigen. In a mouse model of EV71 infection, we observed massive necrotic myositis, different degrees of viral diseases in CNS, and extensive interstitial pneumonia. In mice, EV71 exhibits strong myotropism compared to the neurotropism seen in humans. EV71 antigen was detected in the spinal cord and brainstem of mice. However, there was no clear correlation between mouse SCARB2 and EV71 antigen distribution in the mouse model, consistent with previous results that SCARB2 functions as a receptor for EV71 in humans but not mice. The EV71-induced lesions seen in the mouse model resembled the pathological changes seen in human samples. These results increase our understanding of EV71 pathogenesis and will inform further work developing a mouse model for EV71 infection.
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Computer aided detection of epidural masses on computed tomography scans.
Comput Med Imaging Graph
PUBLISHED: 01-09-2014
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The widespread use of CT imaging and the critical importance of early detection of epidural masses of the spinal canal generate a scenario ideal for the implementation of a computer-aided detection (CAD) system. Epidural masses can lead to paralysis, incontinence and loss of neurological function if not promptly detected. We present, to our knowledge, the first CAD system to detect epidural masses on CT scans. In this paper, spatially constrained Gaussian mixture model (GMM) and supervoxel-based method are proposed for epidural mass detection. The detection is performed on the Gaussian level or the supervoxel level rather than the voxel level. Cross-validation on 40 patients with epidural masses on body CT showed that the supervoxel-based method yielded a significant improvement of performance (82% at 3 false positives per patient) over the spatially constrained GMM method (55% at 3 false positives per patient).
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Cortical shell unwrapping for vertebral body abnormality detection on computed tomography.
Comput Med Imaging Graph
PUBLISHED: 01-09-2014
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The vertebral body is the main axial load-bearing structure of the spinal vertebra. Assessment of acute injury and chronic deformity of the vertebral body is difficult to assess accurately and quantitatively by simple visual inspection. We propose a cortical shell unwrapping method to examine the vertebral body for injury such as fractures and degenerative osteophytes. The spine is first segmented and partitioned into vertebrae. Then the cortical shell of the vertebral body is extracted using deformable dual-surface models. The cortical shell is then unwrapped onto a 2D map and the complex 3D detection problem is effectively converted to a pattern recognition problem on a 2D plane. Characteristic features adapted for different applications are computed and sent to a committee of support vector machines for classification. The system was evaluated on two applications, one for fracture detection on trauma CT datasets and the other on degenerative osteophyte assessment on sodium fluoride PET/CT. The fracture CAD achieved 93.6% sensitivity at 3.2 false positive per patient and the degenerative osteophyte CAD achieved 82% sensitivity at 4.7 false positive per patient.
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Multistate self-assembled micro-morphology transitions controlled by host-guest interactions.
Chem. Commun. (Camb.)
PUBLISHED: 01-03-2014
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The multistate micro-morphology of aggregates in aqueous solution can be manipulated by host-guest interactions between bis-sulfonatocalix[4]arene, ?-CD and a ditopic guest possessing viologen and coumarin moieties.
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Nonlinear mixed-effects (NLME) diameter growth models for individual China-Fir (Cunninghamia lanceolata) trees in Southeast China.
PLoS ONE
PUBLISHED: 01-01-2014
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An individual-tree diameter growth model was developed for Cunninghamia lanceolata in Fujian province, southeast China. Data were obtained from 72 plantation-grown China-fir trees in 24 single-species plots. Ordinary non-linear least squares regression was used to choose the best base model from among 5 theoretical growth equations; selection criteria were the smallest absolute mean residual and root mean square error and the largest adjusted coefficient of determination. To account for autocorrelation in the repeated-measures data, we developed one-level and nested two-level nonlinear mixed-effects (NLME) models, constructed on the selected base model; the NLME models incorporated random effects of the tree and plot. The best random-effects combinations for the NLME models were identified by Akaike's information criterion, Bayesian information criterion and -2 logarithm likelihood. Heteroscedasticity was reduced with two residual variance functions, a power function and an exponential function. The autocorrelation was addressed with three residual autocorrelation structures: a first-order autoregressive structure [AR(1)], a combination of first-order autoregressive and moving average structures [ARMA(1,1)] and a compound symmetry structure (CS). The one-level (tree) NLME model performed best. Independent validation data were used to test the performance of the models and to demonstrate the advantage of calibrating the NLME models.
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[Effects of biochar application on greenhouse gas emission from paddy soil and its physical and chemical properties].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-31-2013
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A field experiment was conducted to investigate the effects of rice straw returning and rice straw biochar and life rubbish biochar application on the greenhouse gas (CH4, CO2 and N2O) emission from paddy soil, its physical and chemical properties, and rice grain yield. Compared with rice straw returning, applying rice straw biochar decreased the cumulative CH4 and N2O emissions from paddy soil significantly by 64.2% - 78.5% and 16.3% - 18.4%, respectively. Whether planting rice or not, the cumulative N2O emission from paddy soil under the applications of rice straw biochar and life rubbish biochar was decreased significantly, compared with that without biochar amendment. Under the condition of no rice planting, applying life rubbish biochar reduced the cumulative CO2 emission significantly by 25.3%. Rice straw biochar was superior to life rubbish biochar in improving soil pH and available potassium content. Both rice straw biochar and life rubbish biochar could increase the soil organic carbon content significantly, but had less effects on the soil bulk density, total nitrogen and available phosphorus contents, cation exchange capacity (CEC), and grain yield. It was suggested that compared with rice straw returning, straw biochar was more effective in improving rice grain yield.
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Quantitative syndesmophyte measurement in ankylosing spondylitis using CT: longitudinal validity and sensitivity to change over 2 years.
Ann. Rheum. Dis.
PUBLISHED: 12-04-2013
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Accurate measurement of syndesmophyte development and growth in ankylosing spondylitis (AS) is needed for studies of biomarkers and of treatments to slow spinal fusion. We tested the longitudinal validity and sensitivity to change of quantitative measurement of syndesmophytes using CT.
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Intranasal Immunization of Mice with Inactivated Virus and Mast Cell Activator C48/80 Elicits Protective Immunity against Influenza H1 but not H5.
Immunol. Invest.
PUBLISHED: 12-02-2013
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Vaccination represents the most economic and effective strategy of preventing influenza pandemics. We previously demonstrated that intranasal immunization of mice with recombinant hemagglutinin and the mast cell activator C48/80 elicited protective immunity against challenge with the 2009 pandemic H1N1 influenza in mice, demonstrating that the novel C48/80 mucosal adjuvant was safe and effective. The present study demonstrated that intranasal immunization with inactivated H1N1 virus and C48/80 elicited protective immunity against lethal challenge with homologous virus, however, when the immunogen was replaced with inactivated H5N1 virus protection was lost. These observations suggested that the adjuvant effects conferred by C48/80 were virus subtype specific and that its use as a broad-spectrum adjuvant for use in immunizations against all influenza viruses needs to be further analyzed.
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Complementary and alternative medicine is expected to make greater contribution in controlling the prevalence of influenza.
Biosci Trends
PUBLISHED: 11-19-2013
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Influenza pandemics are a serious threat to public health in todays world. In the past 10 years, the outbreak of three forms of severe influenza--H5N1, H1N1, and H7N9--has caused tremendous loss of life and property. In order to better cope with pandemics, antivirals such as oseltamivir are being stockpiled in great quantities, placing a substantial burden on government budgets and potentially resulting in massive waste because of the uncertainty as to when an influenza pandemic will strike and whether emerging virus strains will be resistant to the stockpiled drugs. Complementary and alternative medicine (CAM) is generally available, affordable, and commonly used in China and many other countries and CAM has a long track record of fighting influenza. The Chinese Government appropriated funds to intensively investigate herbal medicines in accordance with the principles of evidence-based medicine in order to identify effective, inexpensive, and easily stockpiled medicines. Thus far, several drugs including Shufeng Jiedu capsules, Lianhua Qingwen capsules, Maxing Shigan decoction, Yinqiao powder, and Jinhua Qinggan granules have demonstrated effectiveness in fighting influenza. In the future, CAM is expected to make greater contribution in controlling the prevalence of influenza pandemics.
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An Animal Model of MERS Produced by Infection of Rhesus Macaques With MERS Coronavirus.
J. Infect. Dis.
PUBLISHED: 11-11-2013
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In 2012, a novel coronavirus (CoV) associated with severe respiratory disease, Middle East respiratory syndrome (MERS-CoV; previously known as human coronavirus-Erasmus Medical Center or hCoV-EMC), emerged in the Arabian Peninsula. To date, 114 human cases of MERS-CoV have been reported, with 54 fatalities. Animal models for MERS-CoV infection of humans are needed to elucidate MERS pathogenesis and to develop vaccines and antivirals. In this study, we developed rhesus macaques as a model for MERS-CoV using intratracheal inoculation. The infected monkeys showed clinical signs of disease, virus replication, histological lesions, and neutralizing antibody production, indicating that this monkey model is suitable for studies of MERS-CoV infection.
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A Modified Staged Surgical Intervention for Blepharophimosis-Ptosis-Epicanthus Inversus Syndrome: 125 Cases With Encouraging Results.
Ann Plast Surg
PUBLISHED: 10-30-2013
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Blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) is a rare autosomal dominant condition characterized by typical eyelid malformations that include blepharophimosis, ptosis, epicanthus inversus, and telecanthus.
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Linear correlation between the C-H activation barrier and the C-Cu/C-H bond dissociation energy gap in Cu-promoted C-H activation of heteroarenes.
Chem. Commun. (Camb.)
PUBLISHED: 10-16-2013
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DFT calculations indicate a linear correlation between the C-H activation barrier and the C-Cu/C-H bond dissociation energy gap in Cu-promoted C-H activation of heteroarenes.
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Integrative annotation of variants from 1092 humans: application to cancer genomics.
Science
PUBLISHED: 10-05-2013
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Interpreting variants, especially noncoding ones, in the increasing number of personal genomes is challenging. We used patterns of polymorphisms in functionally annotated regions in 1092 humans to identify deleterious variants; then we experimentally validated candidates. We analyzed both coding and noncoding regions, with the former corroborating the latter. We found regions particularly sensitive to mutations ("ultrasensitive") and variants that are disruptive because of mechanistic effects on transcription-factor binding (that is, "motif-breakers"). We also found variants in regions with higher network centrality tend to be deleterious. Insertions and deletions followed a similar pattern to single-nucleotide variants, with some notable exceptions (e.g., certain deletions and enhancers). On the basis of these patterns, we developed a computational tool (FunSeq), whose application to ~90 cancer genomes reveals nearly a hundred candidate noncoding drivers.
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A framework to measure myocardial extracellular volume fraction using dual-phase low dose CT images.
Med Phys
PUBLISHED: 10-05-2013
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Myocardial extracellular volume fraction (ECVF) is a surrogate imaging biomarker of diffuse myocardial fibrosis, a hallmark of pathologic ventricular remodeling. Low dose cardiac CT is emerging as a promising modality to detect diffuse interstitial myocardial fibrosis due to its fast acquisition and low radiation; however, the insufficient contrast in the low dose CT images poses great challenge to measure ECVF from the image.
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Antigenicity and transmissibility of a novel clade 2.3.2.1 avian influenza H5N1 virus.
J. Gen. Virol.
PUBLISHED: 09-28-2013
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A genetic variant of the H5N1 influenza virus, termed subclade 2.3.2.1, was first identified in Bulgaria in 2010 and has subsequently been found in Vietnam and Laos. Several cases of human infections with this virus have been identified. Thus, it is important to understand the antigenic properties and transmissibility of this variant. Our results showed that, although it is phylogenetically closely related to other previously characterized clade 2.3 viruses, this novel 2.3.2.1 variant exhibited distinct antigenic properties and showed little cross-reactivity to sera raised against other H5N1 viruses. Like other H5N1 viruses, this variant bound preferentially to avian-type receptors, but contained substitutions at positions 190 and 158 of the haemagglutinin (HA) protein that have been postulated to facilitate HA binding to human-type receptors and to enhance viral transmissibility among mammals, respectively. However, this virus did not appear to have acquired the capacity for airborne transmission between ferrets. These findings highlight the challenges in selecting vaccine candidates for H5N1 influenza because these viruses continue to evolve rapidly in the field. It is important to note that some variants have obtained mutations that may gain transmissibility between model animals, and close surveillance of H5N1 viruses in poultry is warranted.
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Novel Avian-Origin Human Influenza A(H7N9) Can Be Transmitted Between Ferrets via Respiratory Droplets.
J. Infect. Dis.
PUBLISHED: 08-29-2013
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The outbreak of human infections caused by novel avian-origin influenza A(H7N9) in China since March 2013 underscores the need to better understand the pathogenicity and transmissibility of these viruses in mammals. In a ferret model, the pathogenicity of influenza A(H7N9) was found to be less than that of an influenza A(H5N1) strain but comparable to that of 2009 pandemic influenza A(H1N1), based on the clinical signs, mortality, virus dissemination, and results of histopathologic analyses. Influenza A(H7N9) could replicate in the upper and lower respiratory tract, the heart, the liver, and the olfactory bulb. It is worth noting that influenza A(H7N9) exhibited a low level of transmission between ferrets via respiratory droplets. There were 4 mutations in the virus isolated from the contact ferret: D678Y in the gene encoding PB2, R157K in the gene encoding hemagglutinin (H3 numbering), I109T in the gene encoding nucleoprotein, and T10I in the gene encoding neuraminidase. These data emphasized that avian-origin influenza A(H7N9) can be transmitted between mammals, highlighting its potential for human-to-human transmissibility.
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Mechanistic Study on Ligand-Controlled Cobalt-Catalyzed Regioselectivity-Switchable Hydroarylation of Styrenes.
Chemistry
PUBLISHED: 07-30-2013
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Density functional theory (DFT) calculations have been performed to study the mechanism of the recently reported Co-catalyzed ligand-controlled hydroarylation of styrenes as a means of preparing 1,1- or 1,2-diarylalkanes. The present study corroborates the previously proposed three-step mechanism, comprising C?H activation (C?H oxidative addition), styrene insertion, and reductive elimination. In the C?H activation and reductive elimination steps, our calculations suggest that styrene does not coordinate to the Co center. In the insertion step, styrene is inserted into the Co?H bond rather than the Co?C bond. Furthermore, the rate- and regiodetermining step is found to be C?C reductive elimination. It is significant that the regioselectivity observed experimentally has been successfully reproduced by our calculations. More importantly, in analyzing the origin of the ligand-controlled regioselectivity, we have found that the steric effects of different ligands mainly determine the observed regioselectivity. Both the shape (i.e., "umbrella-up" or "umbrella-down") and bulkiness of the ligand contribute to the steric effect.
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Rhodium-catalyzed directed C-H cyanation of arenes with N-cyano-N-phenyl-p-toluenesulfonamide.
J. Am. Chem. Soc.
PUBLISHED: 07-12-2013
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A Rh-catalyzed directed C-H cyanation reaction was developed for the first time as a practical method for the synthesis of aromatic nitriles. N-Cyano-N-phenyl-p-toluenesulfonamide, a user-friendly cyanation reagent, was used in the transformation. Many different directing groups can be used in this C-H cyanation process, and the reaction tolerates a variety of synthetically important functional groups.
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Comparative analysis of antibody induction and protection against influenza virus infection by DNA immunization with HA, HAe, and HA1 in mice.
Arch. Virol.
PUBLISHED: 07-05-2013
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Plasmid DNA vaccines are considered alternatives to inactivated influenza virus vaccines to control influenza. Vaccination with a hemagglutinin (HA)-, HA ectodomain (HAe)-, or HA subunit 1 (HA1)-based vaccine can stimulate protective immunity in animals. The aim of this study was to compare their capacity to induce an antibody response and protection against influenza virus infection in mice after DNA vaccination. We constructed three expression vectors encoding full-length HA, HAe, or HA1 of the A/California/07/2009 influenza A virus and designed three animal experiments: (i) BALB/c mice were immunized twice with 30 ?g of the HA, HAe, or HA1 DNA vaccine with high-voltage electroporation (100 V), and 3 weeks after boosting, they were challenged with a lethal dose of virus. (ii) Immunization and challenge were as in experiment i, but with low-voltage electroporation (10 V). (iii) Mice were immunized once with 50 ?g of DNA and challenged 1 week later. The immunogenic effects of the three DNA vaccines were evaluated in terms of antibody titer, survival rate, bodyweight change, and lung viral titer. In all three experiments, both HA and HAe induced higher antibody and neutralization titers than HA1. Following challenge with a lethal mouse-adapted homologous virus, both HA and HAe reduced the viral titers in lung washes or offered better protection from weight loss than HA1 in experiments ii and iii. Thus, HA1 induces a lower immune response than HA or HAe when used as a DNA vaccination. Our data should be valuable in choosing the optimal candidate vaccine when faced with the threat of pandemic influenza.
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Mesenteric vasculature-guided small bowel segmentation on 3-D CT.
IEEE Trans Med Imaging
PUBLISHED: 06-27-2013
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Due to its importance and possible applications in visualization, tumor detection and preoperative planning, automatic small bowel segmentation is essential for computer-aided diagnosis of small bowel pathology. However, segmenting the small bowel directly on computed tomography (CT) scans is very difficult because of the low image contrast on CT scans and high tortuosity of the small bowel and its close proximity to other abdominal organs. Motivated by the intensity characteristics of abdominal CT images, the anatomic relationship between the mesenteric vasculature and the small bowel, and potential usefulness of the mesenteric vasculature for establishing the path of the small bowel, we propose a novel mesenteric vasculature map-guided method for small bowel segmentation on high-resolution CT angiography scans. The major mesenteric arteries are first segmented using a vessel tracing method based on multi-linear subspace vessel model and Bayesian inference. Second, multi-view, multi-scale vesselness enhancement filters are used to segment small vessels, and vessels directly or indirectly connecting to the superior mesenteric artery are classified as mesenteric vessels. Third, a mesenteric vasculature map is built by linking vessel bifurcation points, and the small bowel is segmented by employing the mesenteric vessel map and fuzzy connectness. The method was evaluated on 11 abdominal CT scans of patients suspected of having carcinoid tumors with manually labeled reference standard. The result, 82.5% volume overlap accuracy compared with the reference standard, shows it is feasible to segment the small bowel on CT scans using the mesenteric vasculature as a roadmap.
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The mouse and ferret models for studying the novel avian-origin human influenza A (H7N9) virus.
Virol. J.
PUBLISHED: 06-18-2013
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The current study was conducted to establish animal models (including mouse and ferret) for the novel avian-origin H7N9 influenza virus.
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Synergistic combination of clinical and imaging features predicts abnormal imaging patterns of pulmonary infections.
Comput. Biol. Med.
PUBLISHED: 06-10-2013
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We designed and tested a novel hybrid statistical model that accepts radiologic image features and clinical variables, and integrates this information in order to automatically predict abnormalities in chest computed-tomography (CT) scans and identify potentially important infectious disease biomarkers. In 200 patients, 160 with various pulmonary infections and 40 healthy controls, we extracted 34 clinical variables from laboratory tests and 25 textural features from CT images. From the CT scans, pleural effusion (PE), linear opacity (or thickening) (LT), tree-in-bud (TIB), pulmonary nodules, ground glass opacity (GGO), and consolidation abnormality patterns were analyzed and predicted through clinical, textural (imaging), or combined attributes. The presence and severity of each abnormality pattern was validated by visual analysis of the CT scans. The proposed biomarker identification system included two important steps: (i) a coarse identification of an abnormal imaging pattern by adaptively selected features (AmRMR), and (ii) a fine selection of the most important features from the previous step, and assigning them as biomarkers, depending on the prediction accuracy. Selected biomarkers were used to classify normal and abnormal patterns by using a boosted decision tree (BDT) classifier. For all abnormal imaging patterns, an average prediction accuracy of 76.15% was obtained. Experimental results demonstrated that our proposed biomarker identification approach is promising and may advance the data processing in clinical pulmonary infection research and diagnostic techniques.
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What is Visualize?

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

How does it work?

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

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

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