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Find video protocols related to scientific articles indexed in Pubmed.
Enhancement of the field emission from the TiO2 nanotube arrays by reducing in a NaBH4 solution.
ACS Appl Mater Interfaces
PUBLISHED: 11-20-2014
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A mass of oxygen vacancies are successfully introduced into TiO2 nanotube arrays using low-cost NaBH4 as a reductant in a liquid-phase environment. By controlling and adjusting the reduction time over the range of 0-24 h, the doping concentration of the oxygen vacancy realizes controllable and eventually reaches saturation. Meanwhile, the thermal stability of oxygen vacancies is also investigated, indicating that part of oxygen vacancies remain stable up to 250 °C. In addition, this liquid-phase reduction strategy significantly lowers the requirements of instruments and cost. More interesting, reduced TiO2 nanotube arrays show drastically enhanced field emission performances including substantially decreased turn-on field from 25.01 to 2.65 V/?m, a high current density of 3.5 mA/cm2 at 7.2 V/?m and an excellent field emission stability and repeatability. These results are attributed to the oxygen vacancies obtained by reducing in NaBH4 solution, resulting in a reduced effective work function and an increased conductivity.
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Diagnosis and surgical treatment of cavernous sinus angioleiomyoma: a report of four cases.
Jpn. J. Clin. Oncol.
PUBLISHED: 10-23-2014
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The aims of the study were to retrospectively evaluate the imaging characteristics of cavernous sinus angioleiomyoma and explore appropriate surgical approaches.
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The complete chloroplast genome sequence of Sapindus mukorossi.
Mitochondrial DNA
PUBLISHED: 10-16-2014
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Abstract The complete chloroplast genome sequence of Sapindus mukorossi, a critical Chinese medicine, was reported here. The total length of the chloroplast genome is 160,481?bp long with 37.7% overall GC content. A pair of IRs (inverted repeats) of 27,979?bp were separated by SSC (18,873?bp) and LSC (85,650?bp). It contains 78 protein-coding genes, 30 tRNA genes and four rRNA genes. Sixteen genes contain one or two introns.
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A nanosized {ag@ag12} "molecular windmill" templated by polyoxometalates anions.
Inorg Chem
PUBLISHED: 10-14-2014
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Reaction of multidentate 5-(4-imidazol-1-yl-phenyl)-2H-tetrazole (L) ligand with Ag(I) ions in the existence of H3PW12O40 as anionic template under hydrothermal conditions results in tridecanuclear silver cluster-polyoxometalates hybrid: {Ag13L12}{PW12O40}4·30H2O (1). X-ray single crystal diffraction analysis indicates that the main structural feature of 1 is a nanosized molecular windmill-shaped polynuclear Ag cluster with intriguing {M@M12}-type cuboctahedral topology. The as-synthesized compound exhibits effective photocatalytic activity in the photodegradation of Rhodamine-B (RhB) and antibacterial activity against Escherichia coli, respectively.
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Efficacy of therapy with bortezomib in solid tumors: a review based on 32 clinical trials.
Future Oncol
PUBLISHED: 10-11-2014
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ABSTRACT? The ubiquitin-proteasome system is a major pathway for protein degradation, so that proteasome is now considered as an important target for drug discovery. Bortezomib, the first US FDA-approved proteasome inhibitor now used as a front-line treatment for multiple myeloma. To better understand the effects of bortezomib in cancer treatment, we carried out a review based on 32 published clinical trials to determine whether bortezomib will benefit patients with solid tumors. Information of complete response, partial response, stable disease and objective response rate was collected to assess clinical outcomes. A lack of therapeutic effects was observed when bortezomib was used as a single agent. Meanwhile, when bortezomib treatment was combined with other agents, bortezomib offered no statistically significant response versus these agents alone. High-quality studies are required to better understand the clinically effects of bortezomib and the development of a new generation of proteasome inhibitors is absolutely necessary.
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Disease Diagnosis: Multifunctional PEGylated Multiwalled Carbon Nanotubes for Enhanced Blood Pool and Tumor MR Imaging (Adv. Healthcare Mater. 10/2014).
Adv Healthc Mater
PUBLISHED: 10-11-2014
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Long-circulating multifunctional Gd(III)-loaded multiwalled carbon nanotubes (MWCNTs) modified with polyethylene glycol are designed and synthesized by W. Zhu, X. Shi, and colleagues on page 1568. The formed MWCNTs are water-dispersible, stable, and have good cytocompatibility and antifouling property. With the low r2 /r1 relaxivity ratio and relatively long blood circulation time, the multifunctional MWCNTs are able to be used as a platform for enhanced blood pool and tumor MR imaging.
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Induction of trabecular meshwork cells from induced pluripotent stem cells.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 10-10-2014
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Loss or dysfunction of trabecular meshwork (TM) cells has been associated with the development of pathologically elevated IOP, and it is conceivable that replacement of damaged TM cells could restore function to the TM. We propose that the use of TM-like cells derived from induced pluripotent stem cells (iPSCs) created from a patient's own dermal fibroblasts offers the best solution to this challenge. Here we demonstrate that mouse iPSCs can be induced to differentiate into TM-like cells suitable for autologous transplantation.
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Label-free detection and discrimination of poly-brominated diphenylethers using molecularly imprinted photonic cross-reactive sensor arrays.
Chem. Commun. (Camb.)
PUBLISHED: 10-03-2014
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Molecularly imprinted photonic polymers can serve as ideal sensing elements for efficiently creating cross-reactive sensor arrays. Based on this concept, a new method for sensitive and label-free detection of challenging PBDEs was developed, by which the direct detection and discrimination of trace levels of PBDEs against a high-background of interferents was achieved with 100% accuracy.
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Screening of Key Antioxidant Compounds of Longan (Dimocarpus longan Lour.) Seed Extract by Combining Online Fishing/Knockout, Activity Evaluation, Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, and High-Performance Liquid Chromatography Electrospray Ioniza
J. Agric. Food Chem.
PUBLISHED: 09-24-2014
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To figure out the key phenolic compounds accounting for the antioxidant effects of longan (Dimocarpus longan Lour.) seed extract, online fishing/knockout method, activity evaluation assays, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), and high-performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) analysis were used jointly for the first time. p-Coumaric acid-glycoside, (S)-flavogallonic acid, ellagic acid derivative, and methyl-ellagic acid glucopyranoside were first identified in longan seeds. In addition, our study revealed that ellagic acid as well as its derivative and p-coumaric acid-glycoside had important contribution to the potent antioxidant activity of longan seed extract, while gallic acid, corilagin, (S)-flavogallonic acid, methyl-ellagic acid glucopyranoside, and ethyl gallate showed very little contribution to the total antioxidant activity of longan seed extract. The combining use of the online fishing/knockout method, activity evaluation assays, FT-ICR-MS, and HPLC-ESI-MS analysis is a useful and simple strategy for screening of key bioactive compounds from complex extracts.
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Efficacy of polyunsaturated fatty acids for dry eye syndrome: a meta-analysis of randomized controlled trials.
Nutr. Rev.
PUBLISHED: 09-18-2014
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Dry eye syndrome (DES) is a common ocular disease that significantly affects the quality of life. Polyunsaturated fatty acids (PUFAs) have been used to treat DES; however, randomized controlled trials (RCTs) of PUFA therapy yield discordant results. The objective of this study was to clarify the effects of PUFAs on DES through meta-analysis of all relevant RCTs. To do so, a comprehensive search of PubMed, Embase, the Cochrane Library, ISI Web of Science, and unpublished data was conducted. The changes in clinical and laboratory examinations, symptomatic scores, and rates of relevant symptoms were analyzed. Nine RCTs were included in the current meta-analysis. Compared with placebo, PUFA supplementation was not related to changes in tear film break-up time (weighted mean difference [WMD], 0.33; 95% confidence interval [CI], -0.05 to 0.72), Schirmer's test score (WMD, 0.32; 95%CI, -0.23 to 0.86), or lissamine green staining score (WMD, -0.77; 95%CI, -1.66 to 0.12). However, significant reductions were detected in the symptom score on the ocular surface disease index (WMD, -2.26; 95%CI, -4.44 to -0.08) and in the rate of cells positive for human leukocyte antigen DR (WMD, -5.80; 95%CI, -8.62 to -2.97). This comprehensive meta-analysis supports the use of PUFA supplementation as a potential effective therapy for DES.
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Arthroscopic single-bundle versus triple-bundle anterior cruciate ligament reconstruction.
Acta Orthop Traumatol Turc
PUBLISHED: 09-18-2014
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The aim of this prospective, randomized study was to compare the clinical results of arthroscopic single-bundle (SB) and triple-bundle (TB) anterior cruciate ligament (ACL) reconstruction.
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Norcantharidin enhances TIMP?2 anti?vasculogenic mimicry activity for human gallbladder cancers through downregulating MMP?2 and MT1?MMP.
Int. J. Oncol.
PUBLISHED: 09-12-2014
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Vasculogenic mimicry (VM) is a tumor microcirculation pattern in highly aggressive gallbladder cancers (GBCs). We recently reported the anti?VM activity of norcantharidin (NCTD) in highly aggressive GBC?SD cells and xenografts. In this study, we further investigated that NCTD enhanced tissue inhibitor of matrix metalloproteinase?2 (TIMP?2) anti?VM activity for GBCs and the underlying mechanisms. In vivo and in vitro experiments were performed to determine the effects of NCTD in combination with TIMP?2 on tumor growth, host survival, VM formation, hemodynamic of GBC?SD xenografts, and VM?like networks and malignant phenotypes of GBC?SD cells. Expression of matrix metalloproteinase (MMP)?2 and membrane type 1?MMP (MT1?MMP) among human GBCs, GBC?SD cells and xenografts were determined, respectively. The results showed that expression of MMP?2 and MT1?MMP in human GBCs, GBC?SD cells and xenografts was significantly related to VM in GBCs; a shorter survival time of VM?positive patients with high expression of MMP?2 or MT1?MMP compared to that of the patients with low expression. After treatment with NCTD+TIMP?2, tumor growth, VM formation, VM hemodynamic of the xenografts in vivo were significantly inhibited as compared to control, NCTD or TIMP?2 group, with a prolonged survival time of the xenograft mice (log?rank test, P=0.0115); and these observations were confirmed by VM?like networks by 3?D matrices and showed that proliferation, apoptosis, invasion, migration of GBC?SD cells in vitro were markedly affected. Furthermore, expression of MMP?2 and MT1?MMP in VM formation of the xenografts in vivo and GBC?SD cells in vitro was downregulated as compared to control, NCTD or TIMP?2 group. Thus, we concluded that NCTD enhances TIMP?2 antitumor and anti?VM activities in GBCs through downregulating MMP?2 and MT1?MMP.
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Immunohistochemical staining reveals C-reactive protein existing predominantly as altered conformation forms in inflammatory lesions.
Acta. Biol. Hung.
PUBLISHED: 09-08-2014
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C-reactive protein (CRP) is an established marker of inflammation and has been proposed to play a proinflammatory role in pathologies of several diseases. CRP is primarily produced by the liver and released into circulation as a pentameric molecule composed of five identical subunits. It has been suggested that the activation of the proinflammatory actions of CRP requires sequential conformational changes triggered by local inflammatory conditions. These include the dissociation into the subunit form (monomeric CRP, mCRP) and further reduction of the intra-subunit disulfide bond of mCRP. This model predicts that mCRP is the primary isoform present in inflamed but not healthy tissues, however the supporting evidence is lacking. Herein, we stained tissue samples across multiple anatomical locations from several types of human diseases with highly selective monoclonal antibodies that can differentiate CRP and mCRP. The results indicated that mCRP is the predominant form existing in the lesions. Further immunoblotting of the patient tissue samples revealed the potential presence of reduced mCRP. Together, we conclude that mCRP but not CRP is the major isoform present in local inflammatory lesions, supporting the so-called cascading model of CRP function and regulation.
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The prognostic value of global DNA hypomethylation in cancer: a meta-analysis.
PLoS ONE
PUBLISHED: 09-03-2014
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Aberrant methylation of the global genome has been investigated as a prognostic indicator in various cancers, but the results are controversial and ambiguous.
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Vitronectin silencing inhibits hepatocellular carcinoma in vitro and in vivo.
Future Oncol
PUBLISHED: 09-02-2014
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ABSTRACT Aim: To explore if inhibition of vitronectin can be used for the treatment of hepatocellular carcinoma. Materials & methods: RNAi technology was used to silence the expression of VTN in HepG2 and SMMC 7721 cells. Change of growth characteristics in these cells was evaluated. Results: VTN silencing does not affect growth characteristics of cancer cells in monolayer cell culture, but could suppress the colonized growth of cells in soft agar. VTN-siRNA suppresses colony formation more than 80% compared with that of control in SMMC7721cells and leads to the inhibition of colony formation of over 70% in HepG2 cells. In addition, VTN silencing decreases the size of tumor xenografts in nude mice, particularly in male mice, with an inhibition rate of 46.6%. Conclusion: VTN plays a significant role in the malignant growth of tumor. Inhibition of VTN could potentially be applied for the treatment of hepatocellular carcinoma.
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Photonic metal-organic framework composite spheres: a new kind of optical material with self-reporting molecular recognition.
Nanoscale
PUBLISHED: 09-02-2014
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Exploiting metal-organic framework (MOF) materials as novel building blocks to construct superstructures with extended and enhanced functions represents a big challenge. In biological systems, the ordering of many components is not achieved by interaction of the components with each other, but by interaction of each component with the host protein which provides a matrix to support the entire assembly. Inspired by biological systems, in this work, a general strategy for efficient spatial arrangement of MOF materials was developed by using spherical colloidal crystals as host matrices, affording a new class of highly tunable MOF composite spheres with a series of distinctive properties. It was found that the synergetic combination of the unique features of both MOF and photonic colloidal crystal imparted these hierarchically structured spheres intrinsic optical properties, specific molecular recognition with self-reporting signalling, derivatization capability, and anisotropy. More importantly, the unique photonic band-gap structure integrated in these composite spheres provides a more convenient means to manipulate the photophysical and photochemical behaviour of the trapped guest molecules in MOF nanocavities.
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Myocardial infarction worsens glomerular injury and microalbuminuria in rats with pre-existing renal impairment accompanied by the activation of ER stress and inflammation.
Mol. Biol. Rep.
PUBLISHED: 08-31-2014
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Deterioration of renal function occurs after chronic heart failure in approximately one-third of patients, particularly in those with pre-existing renal impairment such as diabetic nephropathy. Impaired renal function in these patients is always associated with a worse prognosis. However, the mechanisms underlying such deterioration of renal function are still largely unknown. In three separate protocols, we compared 1) sham operation (Ctr, n = 10) with surgically induced myocardial infarction (MI, n = 10); 2) unilateral nephrectomy (UNX, n = 10) with UNX + MI (n = 10); and 3) STZ-induced type 1 diabetes (DB, n = 10) with DB + MI (n = 10). The differences between combined injury models (UNX + MI, DB + MI) and simple MI were also examined. Renal remodeling, function, ER stress (CHOP and GRP78) and inflammation (infiltration of inflammatory cells, NF-?B p65) were evaluated 12 weeks after MI. In common SD rats, MI activated less glomerular ER stress and inflammation, resulting in a minor change of glomerular remodeling and microalbuminuria. However, MI significantly increased the glomerular expression of GRP78 and CHOP in UNX and DB rats. In addition, it also promoted the infiltration of CD4+ T cells, particularly inflammatory cytokine (IFN-?, IL-17, IL-4)-producing CD4+ T cells, and the expression of NF-?B p65 in the glomeruli. By contrast, significant glomerular fibrosis, glomerulosclerosis, podocyte injury and microalbuminuria were found in rats with UNX + MI and DB + MI. MI significantly increased chronic glomerular injury and microalbuminuria at 12 weeks in rats with pre-existing renal impairment, i.e., UNX and DB, but not common SD rats. These changes were accompanied by increased glomerular ER stress and immune-associated inflammation.
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Solvent-assisted electrospray ionization for direct analysis of various compounds (complex) from low/nonpolar solvents and eluents.
Anal. Chem.
PUBLISHED: 08-26-2014
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Electrospray ionization (ESI) is a powerful ionization technique with a wide range of applications. However, the analytes in low/nonpolar solvents cannot be analyzed directly in electrospray ionization-mass spectrometry (ESI-MS), because low/nonpolar solvents are incompatible with ESI, because of their low conductivity. To circumvent this problem, we introduce an electrospray-based ionization method termed solvent-assisted electrospray ionization (SAESI). With the help of electrospray solvents at the tip of the spray needle, compounds in "non-electrospray ionization-friendly" solvents can be ionized directly using solvent-assisted electrospray ionization-mass spectrometry (SAESI-MS). The key features that the assistant solvent can be chosen flexibly and makes little interference to samples lead to better ionization performance in detection of organic reaction intermediates and real-time analysis of polymers and chiral drugs separated by gel permeation chromatography (GPC) and normal phase liquid chromatography (NPLC). Furthermore, it can achieve online hydrogen/deuterium (H/D) exchange reaction and even mitigate the signal suppression caused by strong acid modifiers in liquid chromatography. In addition, all parts of this device are commercially available and it only requires two parameters to be optimized, which makes SAESI easy to handle.
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Comparative analysis of LTR and structural genes in an equine infectious anemia virus strain isolated from a feral horse in Japan.
Arch. Virol.
PUBLISHED: 08-23-2014
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Although equine infectious anemia virus (EIAV) poses a major threat to the equine industry worldwide, the molecular epidemiology of this virus is poorly understood. Recently, an EIAV strain (EIAVMiyazaki2011-A) representing a new monophyletic group was discovered in feral horses in southern Japan. In the present study, the EIAVMiyazaki2011-A proviral genome is compared with evolutionarily divergent EIAV isolates to investigate conservation of functional elements or motifs within the long terminal repeats (LTRs) and structural genes. This analysis represents a significant step forward in increasing understanding of the molecular conservation and variation between geographically distinct strains of this equine lentivirus.
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[Experimental study of repairing severe ligament injury with transgenetic bone mesenchymal stem cells].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-22-2014
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To evaluate the efficacies of transgenetic bone mesenchymal stem cells (BMSCs) carring basic fibroblast growth factor (bFGF) gene on repairing severe ligament injury.
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The preoperative lymphocyte to monocyte ratio predicts clinical outcomes in patients with stage II/III gastric cancer.
Tumour Biol.
PUBLISHED: 08-20-2014
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Recently, lymphocyte to monocyte ratio (LMR) has been reported to be associated with clinical outcomes in some types of cancer but has not been explored in gastric cancer. In this study, we analyzed the association between LMR and clinical outcomes in stage II/III gastric cancer patients. Preoperative LMR calculated from peripheral lymphocyte and monocyte with corresponding clinical features from 426 stage II/III gastric cancer patients was noted. Kaplan-Meier method and Cox regression model were applied for overall survival (OS) and recurrence-free survival (RFS). Related with smaller tumor size (p?
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The comparison of minimally invasive percutaneous nephrolithotomy and retrograde intrarenal surgery for stones larger than 2 cm in patients with a solitary kidney: a matched-pair analysis.
World J Urol
PUBLISHED: 08-13-2014
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To compare the treatment outcomes between retrograde intrarenal surgery (RIRS) and minimally invasive percutaneous nephrolithotomy (MPCNL) for the management of stones larger than 2 cm in patients with solitary kidney.
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Effects and mechanisms of resveratrol on the amelioration of oxidative stress and hepatic steatosis in KKAy mice.
Nutr Metab (Lond)
PUBLISHED: 08-12-2014
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The exact mechanism of the protective role of Resveratrol (Res) in lipid metabolism and oxidative stress is not well elucidated. The present study aimed to investigate the potential benefits and possible mechanisms of Res on the amelioration of oxidative stress and hepatic steatosis in a KKAy mouse model.
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Hypoxia preconditioned mesenchymal stem cells prevent cardiac fibroblast activation and collagen production via leptin.
PLoS ONE
PUBLISHED: 08-12-2014
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Activation of cardiac fibroblasts into myofibroblasts constitutes a key step in cardiac remodeling after myocardial infarction (MI), due to interstitial fibrosis. Mesenchymal stem cells (MSCs) have been shown to improve post-MI remodeling an effect that is enhanced by hypoxia preconditioning (HPC). Leptin has been shown to promote cardiac fibrosis. The expression of leptin is significantly increased in MSCs after HPC but it is unknown whether leptin contributes to MSC therapy or the fibrosis process. The objective of this study was to determine whether leptin secreted from MSCs modulates cardiac fibrosis.
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Proteomics analysis of Mahonia bealei leaves with induction of alkaloids via combinatorial peptide ligand libraries.
J Proteomics
PUBLISHED: 08-08-2014
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Alkaloids are one of the most attractive sources for obtaining active natural products. However, alkaloids exist in the plants as the secondary metabolites with tracing amount, and there is an enormous demand for a large production. In the present study, we aimed to profile the modification of benzylisoquinoline alkaloids in Mahonia bealei seedlings under the binary stress of ultraviolet-B irradiation and dark incubation. Comparative proteomics analysis was carried out to address the underlying proteome variations that accounted for the alkaloid induction under treatment. Thirteen differential proteins were identified in the leaves under binary stress. Of note, the abundance of S-adenosyl-l-methionine synthetase was highly increased to sustain a high concentration of S-adenosyl-l-methionine for the enhanced biosynthesis of alkaloids. Additionally, we presented the application of CPLL to M. bealei leaf proteins. Three new secondary metabolism proteins and 12 additional differential proteins were identified only after CPLL treatment. Six genes in the benzylisoquinoline alkaloid biosynthesis pathway were selected to verify their variable expression using quantitative real time polymerase chain reaction. The results suggest that the benzylisoquinoline alkaloids in M. bealei leaf were increased to eliminate the adverse effect of UV-B exposure. The suppression of photosynthesis and respiratory rate may save an extra energy for the secondary metabolites, and the enhanced N-metabolism may supply sufficient primary metabolite precursors. To our best knowledge, this is the first work aimed at the secondary metabolism proteomic characterization of M. bealei using the CPLL technique. It also presented an effective and innovative process to improve the contents of alkaloids in medicinal plants for industrial production.
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Effects of fish oil on serum lipid profile in dialysis patients: a systematic review and meta-analysis of randomized controlled trials.
Lipids Health Dis
PUBLISHED: 08-08-2014
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The effects of fish oil supplements on lipid profile in dialysis patients are controversial. With increasing interest in the potential health benefits of fish oil, it is important to explore its real effects.
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Motor evoked potential monitoring during surgery of middle cerebral artery aneurysms: a cohort study.
World Neurosurg
PUBLISHED: 08-07-2014
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Motor evoked potential (MEP) monitoring has been widely used in brain or spine surgery to recognize potential damages of the pyramidal motor system. But its ability to detect ischemic injury during middle cerebral artery aneurysm (MCA-AN) surgery remains unclear. Thus, a prospective cohort study was designed to evaluate MEP changes during MCA-AN surgery. No similar study has been reported yet.
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A Molecular Dynamics Investigation of Mycobacterium tuberculosis Prenyl Synthases: Conformational Flexibility, and Implications for Computer-Aided Drug Discovery.
Chem Biol Drug Des
PUBLISHED: 08-06-2014
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With the rise in antibiotic resistance, there is interest in discovering new drugs active against new targets. Here, we investigate the dynamic structures of three isoprenoid synthases from Mycobacterium tuberculosis using molecular dynamics (MD) methods with a view to discovering new drug leads. Two of the enzymes, cis-farnesyl diphosphate synthase (cis-FPPS) and cis-decaprenyl diphosphate synthase (cis-DPPS) are involved in bacterial cell wall biosynthesis while the third, tuberculosinyl adenosine synthase (Rv3378c), is involved in virulence factor formation. The MD results for these three enzymes were then compared with previous results on undecaprenyl diphosphate synthase (UPPS) by means of active site volume fluctuation and principal component analyses. In addition, an analysis of the binding of prenyl diphosphates to cis-FPPS, cis-DPPS, and UPPS utilizing the new MD results is reported. We also screened libraries of inhibitors against cis-DPPS, finding ~1 ?M inhibitors, and used the receiver operating characteristic-area under the curve (ROC-AUC) method to test the predictive power of X-ray and MD-derived cis-DPPS receptors. We found that one compound with potent M. tuberculosis cell growth inhibition activity was an IC50 ~0.5-20 ?M inhibitor (depending on substrate) of cis-DPPS, a ~660 nM inhibitor of Rv3378c as well as a 4.8 ?M inhibitor of cis-FPPS, opening up the possibility of multi-target inhibition involving both cell wall biosynthesis as well as virulence factor formation. This article is protected by copyright. All rights reserved.
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Second-Order Global Consensus in Multiagent Networks With Random Directional Link Failure.
IEEE Trans Neural Netw Learn Syst
PUBLISHED: 08-06-2014
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In this paper, we consider the second-order globally nonlinear consensus in a multiagent network with general directed topology and random interconnection failure by characterizing the behavior of stochastic dynamical system with the corresponding time-averaged system. A criterion for the second-order consensus is derived by constructing a Lyapunov function for the time-averaged network. By associating the solution of random switching nonlinear system with the constructed Lyapunov function, a sufficient condition for second-order globally nonlinear consensus in a multiagent network with random directed interconnections is also established. It is required that the second-order consensus can be achieved in the time-averaged network and the Lyapunov function decreases along the solution of the random switching nonlinear system at an infinite subsequence of the switching moments. A numerical example is presented to justify the correctness of the theoretical results.
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Development of Novel Three-Dimensional Printed Scaffolds for Osteochondral Regeneration.
Tissue Eng Part A
PUBLISHED: 08-05-2014
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As modern medicine advances, various methodologies are being explored and developed in order to treat severe osteochondral defects in joints. However, it is still very challenging to cure the osteochondral defects due to their poor inherent regenerative capacity, complex stratified architecture, and disparate biomechanical properties. The objective of this study is to create novel three-dimensional (3D) printed osteochondral scaffolds with both excellent interfacial mechanical properties and biocompatibility for facilitating human bone marrow mesenchymal stem cell (MSC) growth and chondrogenic differentiation. For this purpose, we designed and 3D printed a series of innovative bi-phasic 3D models that mimic the osteochondral region of articulate joints. Our mechanical testing results showed that our bi-phasic scaffolds with key structures have enhanced mechanical characteristics in compression (a maximum Young's modulus of 31?MPa) and shear (a maximum fracture strength of 5768?N/mm(2)) when compared with homogenous designs. These results are also correlated with numerical simulation. In order to improve their biocompatibility, the scaffolds' surfaces were further modified with acetylated collagen (one of the main components in osteochondral extracellular matrix). MSC proliferation results demonstrated that incorporation of a collagen, along with biomimetically designed micro-features, can greatly enhance MSC growth after 5 days in vitro. Two weeks' chondrogenic differentiation results showed that our novel scaffolds (dubbed "key" scaffolds), both with and without surface collagen modification, displayed enhanced chondrogenesis (e.g., 130%, 114%, and 236% increases in glycosaminoglycan, type II collagen deposition, and total protein content on collagen-modified key scaffolds when compared with homogeneous controls).
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The dependence of the methylation of mercury on the landfill stabilization process and implications for the landfill management.
Chemosphere
PUBLISHED: 07-30-2014
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Mercury species and other chemical characteristics of the leachate from anaerobic and semi-aerobic landfills were analyzed to investigate the factors that control mercury methylation during the landfill stabilization process. At the early landfill stage, the total mercury (THg) and the monomethyl mercury (MMHg) released rapidly and significantly, the THg concentration of the semi-aerobic landfill leachate was obviously higher than that of the anaerobic landfill leachate, while compared with the semi-aerobic landfill, the MMHg concentration in the anaerobic landfill was higher. As the landfill time increased, both of THg and MMHg concentration decreased quickly, the THg concentration in the anaerobic landfill was much higher than that in semi-aerobic landfill, while the MMHg concentration in the anaerobic landfill was lower than that in the semi-aerobic landfill. Generally, the concentrations of dimethyl mercury (DMHg) in the anaerobic landfill leachate were slightly higher than in the semi-aerobic landfill leachate during the stabilization process. A significant positive correlation was found between the DMHg concentrations and the pH value in anaerobic landfill leachate, but this correlation was opposite in the semi-aerobic landfill. The oxidative-reductive potential (ORP) condition was found to be the controlling factor of the methylation process during the early stage. However, the chemical characteristics, especially the TOC concentration, appeared to be the dominant factor affecting the methylation process as the landfill time increased.
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Copper-mediated C-H(sp²)/C-H(sp³) coupling of benzoic acid derivatives with ethyl cyanoacetate: an expedient route to an isoquinolinone scaffold.
Chem. Commun. (Camb.)
PUBLISHED: 07-30-2014
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A facile, copper-mediated, direct C-H(sp(2))/C-H(sp(3)) bond coupling of benzoic acid derivatives with ethyl cyanoacetate by the deployment of an 8-aminoquinoline moiety as a bidentate directing group is disclosed. Such a unique transformation provides a new strategy for the construction of an isoquinolinone scaffold as one of the privileged cores.
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3D Optical Printing of Piezoelectric Nanoparticle-Polymer Composite Materials.
ACS Nano
PUBLISHED: 07-29-2014
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Here we demonstrate that efficient piezoelectric nanoparticle-polymer composite materials can be optically printed into three-dimensional (3D) microstructures using digital projection printing. Piezoelectric polymers were fabricated by incorporating barium titanate (BaTiO3, BTO) nanoparticles into photoliable polymer solutions such as polyethylene glycol diacrylate and exposing to digital optical masks that could be dynamically altered to generate user-defined 3D microstructures. To enhance the mechanical-to-electrical conversion efficiency of the composites, the BTO nanoparticles were chemically modified with acrylate surface groups, which formed direct covalent linkages with the polymer matrix under light exposure. The composites with a 10% mass loading of the chemically modified BTO nanoparticles showed piezoelectric coefficients (d33) of ?40 pC/N, which were over 10 times larger than composites synthesized with unmodified BTO nanoparticles and over 2 times larger than composites containing unmodified BTO nanoparticles and carbon nanotubes to boost mechanical stress transfer efficiencies. These results not only provide a tool for fabricating 3D piezoelectric polymers but lay the groundwork for creating highly efficient piezoelectric polymer materials via nanointerfacial tuning.
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Emergent chiral spin liquid: fractional quantum Hall effect in a kagome Heisenberg model.
Sci Rep
PUBLISHED: 07-28-2014
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The fractional quantum Hall effect (FQHE) realized in two-dimensional electron systems under a magnetic field is one of the most remarkable discoveries in condensed matter physics. Interestingly, it has been proposed that FQHE can also emerge in time-reversal invariant spin systems, known as the chiral spin liquid (CSL) characterized by the topological order and the emerging of the fractionalized quasiparticles. A CSL can naturally lead to the exotic superconductivity originating from the condense of anyonic quasiparticles. Although CSL was highly sought after for more than twenty years, it had never been found in a spin isotropic Heisenberg model or related materials. By developing a density-matrix renormalization group based method for adiabatically inserting flux, we discover a FQHE in a spin-½ isotropic kagome Heisenberg model. We identify this FQHE state as the long-sought CSL with a uniform chiral order spontaneously breaking time reversal symmetry, which is uniquely characterized by the half-integer quantized topological Chern number protected by a robust excitation gap. The CSL is found to be at the neighbor of the previously identified Z2 spin liquid, which may lead to an exotic quantum phase transition between two gapped topological spin liquids.
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An ER-associated miRNA signature predicts prognosis in ER-positive breast cancer.
J. Exp. Clin. Cancer Res.
PUBLISHED: 07-27-2014
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BackgroundBreast cancer patients with positive estrogen receptor (ER) have a better prognosis. However, no prognostic miRNA signature was reported in the ER-positive breast cancer. The aim of the study was to identify and assess the prognostic significance of a miRNA signature in ER-positive breast cancer.MethodsTwo cohorts from The Cancer Genome Atlas (TCGA) dataset were used as training (n =596) and testing set (n =319). Differential expression profiling was identified in the training set. And the prognostic value of the miRNA signature was then assessed in the two cohorts.ResultsA total of 14 miRNAs were observed to be associated with the status of ER by significance analysis of microarrays (SAM) in the training set. Patients were characterized as high score or low score group according to the calculated risk scores from each miRNA. And patients in high score group had worse overall survival compared with those in low score group both in the training and testing set.ConclusionsOur study revealed a miRNA signature including 14 miRNAs associated with ER status which could act as a prognostic marker in ER-positive breast cancer.
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Fibrinogen alpha chain precursor and apolipoprotein A-I in urine as biomarkers for noninvasive diagnosis of calcium oxalate nephrolithiasis: a proteomics study.
Biomed Res Int
PUBLISHED: 07-23-2014
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Calcium oxalate nephrolithiasis is the most common urological disease, but noninvasive and convenient methods of diagnosis are rarely available.
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The placement of peritoneal dialysis catheters: a prospective randomized comparison of open surgery versus "Mini-Perc" technique.
Int Urol Nephrol
PUBLISHED: 07-21-2014
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Currently, most ESRD patients are treated with open surgical technique or with laparoscopic technique. In this study, we examined the role of the ureteroscope-assisted "Mini-Perc" technique versus the modified open surgery in the treatment of ESRD in a prospective randomized manner.
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GRIM?19?mediated Stat3 activation is a determinant for resveratrol?induced proliferation and cytotoxicity in cervical tumor?derived cell lines.
Mol Med Rep
PUBLISHED: 07-21-2014
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Resveratrol is a natural phenol, produced from red grapes, berries and peanuts. Previous studies have suggested that resveratrol exerts anticancer effects. Activation of the signal transducer and activator of transcription 3 (Stat3) is important in cancer. However, the mechanisms by which resveratrol suppresses the Stat3 signaling pathway remain to be elucidated. The aim of the present study was to investigate the effects of resveratrol on GRIM?19?Stat3 signaling in HeLa cells, derived from a cervical tumor. HeLa cells were divided into experimental groups and treated with resveratrol. Western blotting was used to analyze the expression levels of p?Stat3, Stat3, GRIM?19 and ??actin. Cell viability was determined using an MTT assay. The results showed that 100 µM resveratrol suppressed the proliferation and Stat3 phosphorylation in HeLa cells, and induced the expression of the gene associated with retinoid?IFN?induced mortality 19 (GRIM?19) protein. Overexpression of GRIM?19 suppressed the Stat3 signaling pathway in HeLa cells. The Stat3 signaling pathway was activated following the downregulation of GRIM?19 expression using short interfering RNAs (siRNAs). Resveratrol suppressed cell proliferation, however, this effect was decreased through the use of siRNAs. The suppression of Stat3 phosphorylation by resveratrol decreased following treatment with siRNAs. To the best of our knowledge, the present study is among the first to identify GRIM?19?Stat3 signaling as a target of resveratrol, and further elucidates the mechanisms underlying the antitumor activity of resveratrol.
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The archaic chaperone-usher pathways may depend on donor strand exchange for intersubunit interactions.
Microbiology (Reading, Engl.)
PUBLISHED: 07-17-2014
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Subunit-subunit interactions of the classical and alternate chaperone-usher (CU) systems have been shown to proceed through a donor strand exchange (DSE) mechanism. However, it is not known whether DSE is required for intersubunit interactions in the archaic CU system. We have previously shown that the Myxococcus xanthus Mcu system, a member of the archaic CU family that functions in spore coat formation, is likely to use the principle of donor strand complementation to medicate chaperone-subunit interactions analogous to the classical CU pathway. Here we describe the results of studies on Mcu subunit-subunit interactions. We constructed a series of N-terminal-deleted, single amino acid-mutated and donor strand-complemented Mcu subunits, and characterized their abilities to participate in subunit-subunit interactions. It appears that certain residues in both the N and C termini of McuA, a subunit of the Mcu system, play a critical role in intersubunit interactions and these interactions may involve the general principle of DSE of the classical and alternate CU systems. In addition, the specificity of the M. xanthus CU system for Mcu subunits over other spore coat proteins is demonstrated.
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PEGylated polyethylenimine as enhanced T? contrast agent for efficient magnetic resonance imaging.
ACS Appl Mater Interfaces
PUBLISHED: 07-14-2014
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Currently used small molecular magnetic resonance (MR) imaging contrast agents (CAs) in clinics have relatively short half-lives, which has limited the acquisition of high-resolution organ and angiographic images. Therefore, development of a facile strategy for the synthesis of long-circulating CAs with the transforming potential for MR imaging still remains a great challenge. Here we communicate the design and synthesis of PEGylated polyethylenimine (PEI) and its application as enhanced T1 CA for the long-circulating blood pool as well as efficient organ and tumor imaging. In this study, PEI was covalently grafted with gadolinium (Gd(III)) chelator and mPEG-NHS, followed by acetylation of the remaining amines to improve biocompatibility and prolong circulation time. With the relatively long circulation time (3.8 h), the formed multifunctional PEI (PEI.NHAc-DTPA(Gd(III))-mPEG) can be used as an enhanced T1 CA for blood pool and major organ imaging, and could be cleared from the body 96 h post administration through the urinary system. Importantly, the PEI.NHAc-DTPA(Gd(III))-mPEG complexes displayed a strong T1 contrast effect for tumor imaging through the enhanced permeation and retention effect. These findings suggest that the synthesized PEI.NHAc-DTPA(Gd(III))-mPEG may be used as a promising CA for T1 MR imaging of various biological systems.
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Vitreous proteomic analysis of idiopathic epiretinal membranes.
Mol Biosyst
PUBLISHED: 07-12-2014
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To understand the molecular mechanisms of idiopathic epiretinal membranes (iERMs), the vitreous proteomes of patients with iERMs were investigated. The vitreous proteome in patients with iERMs (n = 8) and donor samples (n = 8) was analysed using reversed phase high-performance liquid chromatography (RP-HPLC) coupled with electrospray ionization tandem mass spectrometry (ESI-MS/MS) and GeneGo Metacore™. This research followed the tenets of the Declaration of Helsinki for the use of human subjects. In this current study, 226 significant changes in protein abundance (abundance ratio >2, p < 0.01) were identified in the vitreous proteome of iERM patients compared to normal control vitreous, including 122 proteins that were present at lower levels and 104 proteins that were present at higher levels. In the iERM vitreous samples, complement components, inflammation-related proteins and matrix metalloproteinase were present at higher levels, while normal cytoskeleton proteins were present at lower levels. The top GeneGo pathway was "immune response", the top process network was "inflammation", and the top KEGG pathway was "coagulation cascades". The essential 2-node proteins of the network were estrogen receptor 1 (ESR1) and p300. Among those found at higher levels, ubiquitin-conjugating enzyme E2O (UBE2O) and complement C4A (C4A) were the most abundant proteins, and could be detected in each of the iERM vitreous samples. It can be concluded that iERMs are a complicated pathological process involving inflammation, immune response, and cytoskeleton remolding. UBE2O and C4A may be candidate biomarkers for iERMs.
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[The expression of IL-9, IL-17 and Foxp3 in nasal polyps].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 07-11-2014
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To observe the expression of IL-9, IL-17 and Foxp3 in nasal polyps,so that to explore the role of Th9, Th17/Treg cells imbalance in pathogenesis of nasal polyposis.
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Structural and Functional Analysis of Bacillus subtilis YisP Reveals a Role of Its Product in Biofilm Production.
Chem. Biol.
PUBLISHED: 07-08-2014
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YisP is involved in biofilm formation in Bacillus subtilis and has been predicted to produce C30 isoprenoids. We determined the structure of YisP and observed that it adopts the same fold as squalene and dehydrosqualene synthases. However, the first aspartate-rich motif found in essentially all isoprenoid synthases is aspartate poor in YisP and cannot catalyze head-to-head condensation reactions. We find that YisP acts as a phosphatase, catalyzing formation of farnesol from farnesyl diphosphate, and that it is the first phosphatase to adopt the fold seen in the head-to-head prenyl synthases. Farnesol restores biofilm formation in a ?yisp mutant and modifies lipid membrane structure similarly to the virulence factor staphyloxanthin. This work clarifies the role of YisP in biofilm formation and suggests an intriguing possibility that many of the YisP-like homologs found in other bacteria may also have interesting products and functions.
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Plaquette ordered phase and quantum phase diagram in the spin-1/2 J(1)-J(2) square Heisenberg model.
Phys. Rev. Lett.
PUBLISHED: 07-07-2014
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We study the spin-1/2 Heisenberg model on the square lattice with first- and second-neighbor antiferromagnetic interactions J(1) and J(2), which possesses a nonmagnetic region that has been debated for many years and might realize the interesting Z(2) spin liquid. We use the density matrix renormalization group approach with explicit implementation of SU(2) spin rotation symmetry and study the model accurately on open cylinders with different boundary conditions. With increasing J(2), we find a Néel phase and a plaquette valence-bond (PVB) phase with a finite spin gap. From the finite-size scaling of the magnetic order parameter, we estimate that the Néel order vanishes at J(2)/J(1)?0.44. For 0.5
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Construction of photoelectrochemical thrombin aptasensor via assembling multilayer of graphene-CdS nanocomposites.
Biosens Bioelectron
PUBLISHED: 07-05-2014
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A photoelectrochemical (PEC) aptasensor for highly sensitive and specific detection of thrombin was developed by using graphene-CdS nanocomposites multilayer as photoactive species and electroactive mediator hexaammineruthenium(III) chloride ( [Formula: see text] ) as signal enhancer. Graphene-CdS nanocomposites (G-CdS) were synthesized by one-pot reduction of oxide graphene and CdCl2 with thioacetamide. The photoactive multilayer was prepared by alternative assembly of the negatively charged 3-mercaptopropionic acid modified graphene-CdS nanocomposites (MPA-G-CdS) and the positively charged polyethylenimine (PEI) on ITO electrode. This layer-by-layer assembly method enhanced the stability and homogeneity of the photocurrent readout of G-CdS. Thrombin aptamer was covalently bound to the multilayer by using glutaraldehyde as cross-linking. Electroactive mediator [Formula: see text] could interact with the DNA phosphate backbone and thus facilitated the electron transfer between G-CdS multilayer and electrode and enhanced the photocurrent. Hybridizing of a long complementary DNA with thrombin aptamer could increase the adsorption amount of [Formula: see text] , which in turn boosted the signal readout. In the presence of target thrombin, the affinity interaction between thrombin and its aptamer resulted in the long complementary DNA releasing from the G-CdS multilayer and decreasing of photocurrent signal. On the basis of G-CdS multilayer as the photoactive species, [Formula: see text] as an electroactive mediator, and aptamer as a recognition module, a high sensitive PEC aptasensor for thrombin detection was proposed. The thrombin aptasensor displayed a linear range from 2.0pM to 600.0pM and a detection limit of 1.0pM. The present strategy provided a promising ideology for the future development of PEC biosensor.
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MicroRNA-21 and the clinical outcomes of various carcinomas: a systematic review and meta-analysis.
BMC Cancer
PUBLISHED: 06-30-2014
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MicroRNA-21 (miR-21) has been suggested to play a significant role in the prognosis of carcinoma. The recognition of novel biomarkers for the prediction of cancer outcomes is urgently required. However, the potential prognostic value of miR-21 in various types of human malignancy remains controversial. The present meta-analysis summarises and analyses the associations between miR-21 status and overall survival (OS) in a variety of tumours.
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Equine infectious anemia virus in Japan: Viral isolates V70 and V26 are of North American not Japanese origin.
Vet. Microbiol.
PUBLISHED: 06-28-2014
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The virulent and attenuated equine infectious anemia virus (EIAV) isolates V70 and V26 are reported as originating from Japan in a number of high profile publications resulting in their inclusion as "Asian viruses" in many subsequent phylogenetic and epidemiological studies. However, the widespread perception that V70 and V26 are Japanese is probably incorrect as the original published literature coupled with genomic analysis demonstrate that these viruses are almost certainly derived from the North America strain EIAVWyoming strain.
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Molecularly Imprinted Photonic Polymers as Sensing Elements for the Creation of Cross-Reactive Sensor Arrays.
Chemistry
PUBLISHED: 06-24-2014
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By combining molecular imprinting and colloidal crystal templating, molecularly imprinted inverse-opal photonic polymers (MIPPs) acting as sensing elements have been exploited to create sensor arrays for the first time. With this new strategy, abundant sensing elements with differential sensing abilities were easily accessible. Because of the unique hierarchical porous structure integrated in each sensing element, high sensitivity and selectivity, fast response and self-reporting (label-free) detection could be simultaneously achieved. All these fascinating features indicate that MIPPs are ideal sensing elements for creating sensor arrays. By integrating the individual sensing elements on a substrate, the formed array chip delivers better portability and high-throughput capability. As a demonstration, six kinds of contaminants were selected as analytes. The detection and discrimination of these analytes and even their mixtures in a wide range of concentrations, particularly trace amounts of analyte against a high background of other components, could be achieved, indicating the powerful capability of MIPPs-based sensor array for sensing. These results suggest that the described strategy opens a new route for sensor array creation and should find important applications in a wide range of areas.
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Reconstruction of Penile Urethra With the 3-Dimensional Porous Bladder Acellular Matrix in a Rabbit Model.
Urology
PUBLISHED: 06-20-2014
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To evaluate the effect of reconstruction of penile urethra with the 3-dimensional (3-D) porous bladder acellular matrix (BAM) in a rabbit model.
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The role of D-dimers in the diagnosis of acute aortic dissection.
Mol. Biol. Rep.
PUBLISHED: 06-19-2014
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Acute aortic dissection (AAD) is a life threatening cardiovascular medical emergency with a poor prognosis. To explore the utility of D-dimers (DD) in the diagnosis of AAD, we performed a prospective study and conducted a meta-analysis of previous studies. 368 suspected patients were enrolled, including AAD n = 89, PE n = 12, AMI n = 167, normal controls n = 100. All patients had a DD test immediately after admission. We then performed a comprehensive computer search to identify studies investigating using DD as a screening tool for AAD. Finally, we pooled these data to estimate sensitivity, specificity, positive and negative likelihood ratios (LRs) by using DerSimonian-Laird random-effects models. The DD concentrations in the AAD group were significantly higher than those in the AMI and normal control groups. However, the DD level of 500 ng/ml had a poor sensitivity of 51.7 % and specificity of 89.2 % in the diagnosis of AAD. Subgroup analyses found that DD only showed a well discriminative ability of distinguishing AAD patients from normal controls (specificity and positive LR was 97 % and 17.2, respectively). The pooled sensitivity, specificity, positive and negative LR in our meta-analysis was 89, 68 %, 2.71, 0.07, respectively. In conclusion, our results suggest that plasma DD levels cannot add to the certainty of AAD diagnosis and it is not a good biomarker for AAD. In the future, prospective research on patients from many parts of the world is warranted to validate our findings. In addition, different controls, methods of plasma DD assays and other factors should be considered.
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Gasification of cyanobacterial in supercritical water.
Environ Technol
PUBLISHED: 06-10-2014
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Cyanobacterial collected from eutrophic freshwater lakes constituted intractable waste with a rich algae biomass content. Supercritical water gasification (SCWG) was proposed to treat the cyanobacterial and to produce hydrogen for energy. The H 2 yield reached 2.92 mol/kg at reaction conditions of 500 °C, 30 min and 22 MPa; this yield accounted for 26% of the total gaseous products. Abundant ammonia and dissolved reactive phosphorous were concentrated in the liquid product, which could be recovered and used as a liquid fertilizer. Solid residue, which accounted only for about 1% of the wet weight, was mainly composed of coke and ash. The efficiency of H 2 production was better than that from other biomass, because of the abundant organic matter in cyanobacterial. Thus, cyanobacterial are an ideal biomass feedstock for H 2 production from SCWG.
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High-flexion posterior-substituting versus cruciate-retaining prosthesis in total knee arthroplasty: functional outcome, range of motion and complication comparison.
Arch Orthop Trauma Surg
PUBLISHED: 05-11-2014
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Currently, a high-flexion cruciate-retaining knee prosthesis has been designed to allow greater advantage after total knee arthroplasty (TKA). The present study was conducted to compare functional outcome, range of motion (ROM) as well as complications in subjects who underwent either a high-flexion cruciate-retaining (HFCR, Group I) or a high-flexion posterior-substituting (HFPS, Group II) prosthesis TKA.
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Retrospective comparative study of the effects of dendritic cell vaccine and cytokine-induced killer cell immunotherapy with that of chemotherapy alone and in combination for colorectal cancer.
Biomed Res Int
PUBLISHED: 05-08-2014
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This retrospective study determined the delayed-type hypersensitivity (DTH) skin test and safety of dendritic cell (DC) vaccine and cytokine-induced killer (CIK) cell immunotherapy and the survival compared to chemotherapy in 239 colorectal cancer (CRC) patients.
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Novel concave-convex electrode for colonic anastomoses by radiofrequency thermo-fusion.
Surg Endosc
PUBLISHED: 04-25-2014
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Successful vascular sealing by radiofrequency (RF)-induced tissue fusion is well established. The present study reports on a novel electrode structure design together with its experimental assessment for RF thermo-fusion of porcine colonic segments.
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Apoptosis, necrosis, and autophagy in mouse intestinal damage after 15-Gy whole body irradiation.
Cell Biochem. Funct.
PUBLISHED: 03-27-2014
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Enterocytes die during high-dose radiation exposure in radiation accidents. The modality of cell death has a profound effect on the therapeutic response. The ilea from mice with 15?Gy total body irradiation (TBI) were drawn, morphological features observed by hematoxylin and eosin staining and transmission electron micrographs. The biochemical features of mouse ileum presented with the structure were cleaved Caspase-3 (apoptosis marker), Light Chain 3 (LC3)-I's conversion to LC3-II (autophagy marker) and high mobility group box chromosomal protein 1's secretion (necrosis marker). Then, the autophagy inhibitor (3-methyladenine), caspase inhibitor (Z-VAD-FMK) or necrosis inhibitor (necrostatin) was used to prevent death. Apoptosis, autophagy and necrosis were all appeared in the ileum, but necrosis had the biggest size; the use of 3-methyladenine and Z-VAD-FMK prolong one day's life of the mice after 15?Gy TBI, necrostatin significantly extended the lifespan of 15?Gy irradiated mice (p?
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The crosstalk between Dectin1 and TLR4 via NF-?B subunits p65/RelB in mammary epithelial cells.
Int. Immunopharmacol.
PUBLISHED: 03-20-2014
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Mammary epithelial cells (MECs), as part of the functional unit of the udder, are not only responsible for the synthesis of many components in milk that provide necessary nutritional and immunological support to the offspring, but also playing essential roles in the reaction to mastitis pathogens and the initiation of the immune signaling pathway. There are contributions of MECs to the signaling and production of pathogen associated molecular patterns (PAMPs) such as LPS, lipoteichoic acid (LTA), and ?-glucans, but the crosstalk of different PAMPs induces signalings and productions in rat MEC that need further study. In the present study, we have demonstrated that ?-glucan up-regulates Dectin1 and LPS up-regulates TLR4 directly, as confirmed by generation of siDectin1 and siTLR4 in rat MECs. Then our results have described that either ?-glucan or LPS can activate RelB and/or p65 in rat MECs. Furthermore, the association of p65 and RelB has been analyzed that collaboration of ?-glucan and LPS promotes p65/RelB heterodimers, producing inflammatory responses in rat MECs. In conclusion, summary of our present results suggests that ?-glucan can be considered as a potential immuno-modulator, which s with TLR4 via NF-?B subunits to initiate and regulate the innate immunity in rat MECs.
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GW4064, a farnesoid X receptor agonist, upregulates adipokine expression in preadipocytes and HepG2 cells.
World J. Gastroenterol.
PUBLISHED: 03-14-2014
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To investigate the effect of GW4064 on the expression of adipokines and their receptors during differentiation of 3T3-L1 preadipocytes and in HepG2 cells.
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To repeat or to recreate: A contralateral posterior interhemispheric transfalcine transprecuneus approach for recurrent meningiomas at the trigone of the lateral ventricle.
J Clin Neurosci
PUBLISHED: 03-13-2014
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Surgery in the trigone of the lateral ventricle remains a challenge for neurosurgeons. In recurrent trigonal meningiomas (RTM), the disturbance of normal anatomic structures and adhesion due to previous surgeries, significant oedema, and their malignant properties heighten the difficulties associated with their surgical removal. This report presents two patients with recurrent meningiomas with anaplastic transformation at the trigone of the lateral ventricle who were successfully treated with contralateral posterior interhemispheric transfalcine transprecuneus (CITT) surgeries. The primary tumours were both completely removed through a transparietal approach in previous surgeries, but both patients experienced hemianopsia postoperatively. The second surgeries resulted in the complete resection of the recurrent tumours without any new-onset neurological dysfunction. The CITT approach suits most trigonal lesions with advantages of optic radiation preservation, reduction of retraction, improved exposure, and navigation accuracy, and because it addresses the origin of the trigonal lesion. Although the characteristics of RTM heighten the difficulty associated with their surgical removal, these challenges highlight the advantages of the CITT approach. In conclusion, the CITT approach is a safe and effective procedure for the removal of RTM.
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Urinary TGF-1 has a supplementary value in predicting renal function recovery post unilateral ureteral obstruction.
Int Urol Nephrol
PUBLISHED: 03-12-2014
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To evaluate whether urine transforming growth factor-?1 (TGF-?1) can help identifying kidneys that would recover their function after drainage of unilateral ureteric obstructive.
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Transplantation of SIRT1-engineered aged mesenchymal stem cells improves cardiac function in a rat myocardial infarction model.
J. Heart Lung Transplant.
PUBLISHED: 03-08-2014
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Previous studies have demonstrated that biological aging has a negative influence on the therapeutic effects of mesenchymal stem cells (MSCs)-based therapy. Using a rat myocardial infarction (MI) model, we tested the hypothesis that silent mating type information regulation 2 homolog 1 (SIRT1) may ameliorate the phenotype and improve the function of aged MSCs and thus enhance the efficacy of aged MSCs-based therapy.
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Prophylactic effects of quercetin and hyperoside in a calcium oxalate stone forming rat model.
Urolithiasis
PUBLISHED: 03-03-2014
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Quercetin and hyperoside (QH) are the two main constituents of the total flavone glycosides of Flos Abelmoschus manihot, which has been prescribed for treating chronic kidney disease for decades. This study aimed to investigate the effect of QH on calcium oxalate (CaOx) formation in ethylene glycol (EG)-fed rats. Rats were divided into three groups: an untreated stone-forming group, a QH-treated stone-forming group (20 mg/kg/day) and a potassium citrate-treated stone-forming group (potassium citrate was a worldwide-recognized calculi-prophylactic medicine). Ethylene glycol (0.5 %) was administered to the rats during the last week, and vitamin D3 was force-fed to induce hyperoxaluria and kidney calcium oxalate crystal deposition. 24 h urine samples were collected before and after inducing crystal deposits. Rats were killed and both kidneys were harvested after 3 weeks. Bisected kidneys were examined under a polarized light microscope for semi-quantification of the crystal-formation. The renal tissue superoxide dismutase and catalase levels were measured by Western blot. QH and potassium citrate have the ability to alkalinize urine. The number of crystal deposits decreased significantly in the QH-treated stone-forming group as compared to the other groups. Superoxide dismutase and catalase levels also increased significantly in the QH-treated stone-forming group, as compared with the untreated stone-forming group. QH administration has an inhibitory effect on the deposition of CaOx crystal in EG-fed rats and may be effective for preventing stone-forming disease.
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Robust carbon dioxide reduction on molybdenum disulphide edges.
Nat Commun
PUBLISHED: 02-26-2014
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Electrochemical reduction of carbon dioxide has been recognized as an efficient way to convert carbon dioxide to energy-rich products. Noble metals (for example, gold and silver) have been demonstrated to reduce carbon dioxide at moderate rates and low overpotentials. Nevertheless, the development of inexpensive systems with an efficient carbon dioxide reduction capability remains a challenge. Here we identify molybdenum disulphide as a promising cost-effective substitute for noble metal catalysts. We uncover that molybdenum disulphide shows superior carbon dioxide reduction performance compared with the noble metals with a high current density and low overpotential (54?mV) in an ionic liquid. Scanning transmission electron microscopy analysis and first principle modelling reveal that the molybdenum-terminated edges of molybdenum disulphide are mainly responsible for its catalytic performance due to their metallic character and a high d-electron density. This is further experimentally supported by the carbon dioxide reduction performance of vertically aligned molybdenum disulphide.
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Gene expression pattern of insect fat body cells from in vitro challenge to cell line establishment.
In Vitro Cell. Dev. Biol. Anim.
PUBLISHED: 02-20-2014
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The cell lines provided excellent tools to understand the mechanism of biological phenomenon at the cellular and molecular levels. The continuous development of new cell culture technology is both of interest for use in biochemical, immunology, and virological studies. The transformation of cells of the primary culture is a key procedure for insect cell line establishment but little is known about the molecular basis of these changes. Here, we found that the cell cycle progression of the cells of the primary culture was delayed or arrested in G2/M by fluorescence-activated cell sorting analysis. In this study, two subtractive cDNA libraries were constructed to screen for immortal-related genes of Spodoptera exigua (Lepidoptera: Noctuidae). Gene ontology and pathway analysis indicated that members of the oxidative phosphorylation, PI3K-Akt signaling pathway, and the ubiquitin proteasome pathway are involved in processes leading toward cell immortalization merit further investigation. Our findings suggest that tumor-related genes or target genes of these pathways may contribute to the transformation of primary cell through regulation of G2/M cell cycle progression.
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Role of non-coding RNAs in pancreatic cancer: the bane of the microworld.
World J. Gastroenterol.
PUBLISHED: 02-12-2014
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Our understanding of the mechanisms underlying the development of pancreatic cancer has been greatly advanced. However, the molecular events involved in the initiation and development of pancreatic cancer remain inscrutable. None of the present medical technologies have been proven to be effective in significantly improving early detection or reducing the mortality/morbidity of this disease. Thus, a better understanding of the molecular basis of pancreatic cancer is required for the identification of more effective diagnostic markers and therapeutic targets. Non-coding RNAs (ncRNAs), generally including microRNAs and long non-coding RNAs, have recently been found to be deregulated in many human cancers, which provides new opportunities for identifying both functional drivers and specific biomarkers of pancreatic cancer. In this article, we review the existing literature in the field documenting the significance of aberrantly expressed and functional ncRNAs in human pancreatic cancer, and discuss how oncogenic ncRNAs may be involved in the genetic and epigenetic networks regulating functional pathways that are deregulated in this malignancy, particularly of the ncRNAs' role in drug resistance and epithelial-mesenchymal transition biological phenotype, with the aim of analyzing the feasibility of clinical application of ncRNAs in the diagnosis and treatment of pancreatic cancer.
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Particle-stabilizers modified from indica rice starches differing in amylose content.
Food Chem
PUBLISHED: 02-05-2014
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Octenyl succinic anhydride (OSA) starches were prepared from four cultivars of native indica rice starches with amylose contents of 1.90%, 18.01%, 25.40% and 26.98% (w/w). The emulsion stability and microstructure of the oil-in-water Pickering emulsions (soybean oil/water, 1/2, v/v) stabilized by OSA starch particles were investigated. Results indicated that the average droplet sizes of the emulsions were in the range of 10-70 ?m, depending on starch cultivars. During 100 days of storage, the emulsions made from OSA starches (degree of substitution: 0.0287-0.0294) were stable. Optical microscopy showed that starch particles were accumulated at the oil-water interface in the form of a densely packed layer, which prevented the flocculation and coalescence of oil droplets by a steric mechanism. Moreover, the emulsification of particle-stabilizers was positively correlated with degree of substitution (P<0.01) but had no obvious correlation with amylose content and pasting properties.
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Magnetic resonance standard for cavernous sinus hemangiomas: proposal for a diagnostic test.
Eur. Neurol.
PUBLISHED: 01-19-2014
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By definition, a cavernous sinus is a vascular plexus. A hemangioma is a vascular tumor which is rich in vascular plexus and caused by vascular deformity or tumor-like proliferation. Radiosurgery can effectively control the growth of smaller cavernous sinus hemangiomas (CSHs). This paper aimed to quantify the MRI characteristics of CSHs which provided a basis for further treatment.
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Azithromycin Reduces the Production of ?-hemolysin and Biofilm Formation in Staphylococcus aureus.
Indian J. Microbiol.
PUBLISHED: 01-16-2014
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Staphylococcus aureus causes a broad range of life-threatening diseases in humans. This bacterium produces a large number of extracellular virulence factors that are closely associated with specific diseases which are controlled by quorum sensing. In this study, we show that azithromycin was active against methicillin-resistant Staphylococcus aureus (MRSA) strains with MICs ranged from 32 to 64 ?g/mL. Azithromycin at subinhibitory concentration, markedly reduced the production of ?-hemolysin at (1/16MIC, 1/8MIC) and biofilm formation at (1/16MIC, 1/8MIC), respectively. The results indicated that sub-inhibitory concentrations of azithromycin decreased the production of ?-hemolysin and biofilm formation in MRSA in a dose-dependent manner. Therefore, azithromycin may be useful in the treatment of ?-hemolysin producing and biofilm formation MRSA infections.
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Interleukin-23A is associated with tumor growth in Helicobacter-pylori-related human gastric cancer.
Cancer Cell Int.
PUBLISHED: 01-01-2014
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Interleukin (IL)-23 is one of the newly identified inflammatory cytokines, and inflammation is also known to be related to the development of gastric cancer (GC). The role of IL-23 in gastric cancer, however, is largely unknown. In the present study, we investigated the expression and possible role of IL-23A in human GC.
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Prevalence and Molecular Characterization of Cryptosporidium in Goats across Four Provincial Level Areas in China.
PLoS ONE
PUBLISHED: 01-01-2014
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This study assessed the prevalence, species and subtypes of Cryptosporidium in goats from Guangdong Province, Hubei Province, Shandong Province, and Shanghai City of China. Six hundred and four fecal samples were collected from twelve goat farms, and the overall infection rate was 11.4% (69/604). Goats infected with Cryptosporidium were found in eleven farms across four provincial areas, and the infection rate ranged from 2.9% (1/35) to 25.0% (9/36). Three Cryptosporidium species were identified. Cryptosporidium xiaoi (45/69, 65.2%) was the dominant species, followed by C. parvum (14/69, 20.3%) and C. ubiquitum (10/69, 14.5%). The infection rate of Cryptosporidium spp. was varied with host age and goat kids were more susceptible to be infected than adult goats. Subtyping C. parvum and C. ubiquitum positive samples revealed C. parvum subtype IIdA19G1 and C. ubiquitum subtype XIIa were the most common subtypes. Other C. parvum subtypes were detected as well, such as IIaA14G2R1, IIaA15G1R1, IIaA15G2R1 and IIaA17G2R1. All of these subtypes have also been detected in humans, suggesting goats may be a potential source of zoonotic cryptosporidiosis. This was the first report of C. parvum subtypes IIaA14G2R1, IIaA15G1R1 and IIaA17G2R1 infecting in goats and the first molecular identification of C. parvum and its subtypes in Chinese goats.
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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.