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Find video protocols related to scientific articles indexed in Pubmed.
Unusual Fe(CN)63-/4- capture induced by synergic effect of electropolymeric cationic surfactant and graphene: Characterization and biosensing application.
ACS Appl Mater Interfaces
PUBLISHED: 11-20-2014
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Herein, a special microheterogeneous system for Fe(CN)63-/4- capture was constructed based on graphene (GN) and the electropolymeric cationic surfactant, an amphiphilic pyrrole derivative, (11-pyrrolyl-1-yl-undecyl) triethylammonium tetrafluoroborate (A2). The morphology of the system was characterized by scanning electron microscope. The redox properties of the entrapped Fe(CN)63-/4- were investigated by cyclic voltammetry and UV-visible spectrometry. The entrapped Fe(CN)63-/4- exhibited highly electroactive with stable and symmetrical cyclic voltammetric signal. A dramatic negative shift in the half wave potential can be obtained due to the unusual Fe(CN)63-/4- partitioning in in this microheterogeneous system based on poly(A2+GN). Finally, the entrapped Fe(CN)63-/4- was applied in the construction of the enhanced biosensors to hydrogen peroxide and sulfide.
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Construction of dentate bonded TiO2-CdSe heterostructures with enhanced photoelectrochemical properties: versatile labels toward photoelectrochemical and electrochemical sensing.
Dalton Trans
PUBLISHED: 11-20-2014
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A facile synthetic route for TiO2-CdSe heterostructures was proposed based on dentate binding of TiO2 to carboxyl. Carboxyl functionalized CdSe quantum dots (CF-CdSe QDs) were successfully bonded onto TiO2 nanoparticles (NPs), which could significantly improve the photoelectrochemical (PEC) properties of TiO2 NPs. This is ascribed to the fact that CdSe QDs with a narrow band gap could be stimulated under visible light irradiation, and the energy levels of TiO2 NPs and CF-CdSe QDs are aligned with an electrolyte solution. High resolution transmission electron microscopy images revealed the heterostructures of the TiO2-CdSe composites. Ultraviolet visible spectroscopy, photoluminescence emission spectroscopy and electrochemical impedance spectroscopy analysis exhibited that the prepared TiO2-CdSe heterostructures have improved light absorption, charge separation efficiency and electron transfer ability in the visible light region. TiO2-CdSe heterostructures were used as versatile labels for fabrication of PEC and electrochemical immunosensors, and human immune globulin G (HIgG) was used as a model analyte. The immunosensor showed high sensitivity, a low detection limit and a wide linear range, which could be applied in practical serum sample analysis. The constructed TiO2-CdSe heterostructures would have potential applications in photocatalysis, aptasensors, cytosensors and other areas of nanotechnology.
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Efficacy and Safety of Metformin for Patients with Type 1 Diabetes Mellitus: A Meta-Analysis.
Diabetes Technol. Ther.
PUBLISHED: 11-05-2014
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Abstract Background: Insulin is an essential therapy for patients with type 1 diabetes mellitus (T1DM). With the progression of the disease, many patients with T1DM may have an increased prevalence of insulin resistance; thus the common standard insulin therapy requires a high insulin dosage (>1 unit/kg/day) and is usually associated with many side effects. Studies have shown that metformin may benefit those insulin-resistant individuals with T1DM. This meta-analysis was performed to provide the evidence of clinical efficacy and safety of metformin in T1DM. Materials and Methods: We conducted a search on Medline, EMBASE, and the Cochrane Library for relevant studies published before May 2014 based on "metformin" and "diabetes mellitus, type 1." The following outcomes were evaluated: hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), lipid metabolism, weight, insulin dosage, hypoglycemia, diabetic ketoacidosis, or gastrointestinal adverse events (AEs). The meta-analysis was performed using Review Manager version 5.2 software (The Nordic Cochrane Centre, Copenhagen, Denmark). Results: In total, eight randomized controlled trials were included. Metformin was associated with a reduction in daily insulin dosage, body weight, total cholesterol level, low-density lipoprotein level, and high-density lipoprotein level but an increase in risk of gastrointestinal AEs compared with placebo treatment in T1DM patients. No significant difference was found between the metformin group and the placebo group in HbA1c level, FPG level, or triglycerides level. No significant difference was found between the metformin group and the placebo group in the risk of severe hypoglycemia or diabetic ketoacidosis. Conclusions: Metformin may decrease the daily insulin dosage, body weight, and lipid levels in T1DM. However, metformin does not increase the incidence of hypoglycemia and ketoacidosis. High-quality, large-sample, and long-term follow-up clinical trials are needed to confirm these conclusions.
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Optimization of extraction of prodelphinidins from bayberry (Myrica rubra Sieb. et Zucc.) leaves.
J Food Sci Technol
PUBLISHED: 10-21-2014
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The antioxidant activity of bayberry leaf extract determined by DPPH• and FRAP assay was comparable with ascorbic acid. Prodelphinidins in the extract had significant positive correlation with the antioxidant activities of bayberry leaf extract. The correlation coefficients (R) were 0.963 and 0.970 for DPPH• and FRAP assay, respectively. In order to develop a new natural antioxidant, a central composite design was employed and the yield of prodelphinidins was selected as the response value to investigate the extraction. The best possible combination of acetone concentration, time, solid-liquid ratio and temperature was obtained for the maximum extraction of prodelphinidins by using response surface methodology (RSM). The extraction yield of prodelphinidins was affected significantly by process variables. The optimal conditions obtained by RSM include 56.93 % acetone, 31.98 min time, 1: 44.52 solid-liquid ratio, and 50.00 °C temperature. Under the optimum condition, the experimental yield of prodelphinidins was 117.3?±?5.1 mg/g, which was not different from the predicted value significantly.
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Assessment of Corneal Epithelial Thickness in Dry Eye Patients.
Optom Vis Sci
PUBLISHED: 10-04-2014
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To investigate the features of corneal epithelial thickness topography with Fourier-domain optical coherence tomography (OCT) in dry eye patients.
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Statistics-based electron Moiré technique: a novel method applied to the characterization of mesoporous structures.
Nanoscale
PUBLISHED: 10-03-2014
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We report a statistics-based electron Moiré method in this study, for the first time, to cope with the highly distorted fringes and to realize the measurement of disordered mesoporous structures. A grey-level co-occurrence matrix is employed to determine the predominant period and the orientation of a randomly distributed Moiré fringe pattern and consequently to obtain the corresponding period/orientation of the test structures. The basic principles, the method descriptions, and the relevant experiments are discussed in detail. Mesoporous alumina films are investigated with the proposed method.
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A Zebrafish Embryo Behaves both as a "Cortical Shell - Liquid Core" Structure and a Homogeneous Solid when Experiencing Mechanical Forces.
Microsc. Microanal.
PUBLISHED: 09-27-2014
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Mechanical properties are vital for living cells, and various models have been developed to study the mechanical behavior of cells. However, there is debate regarding whether a cell behaves more similarly to a "cortical shell - liquid core" structure (membrane-like) or a homogeneous solid (cytoskeleton-like) when experiencing stress by mechanical forces. Unlike most experimental methods, which concern the small-strain deformation of a cell, we focused on the mechanical behavior of a cell undergoing small to large strain by conducting microinjection experiments on zebrafish embryo cells. The power law with order of 1.5 between the injection force and the injection distance indicates that the cell behaves as a homogenous solid at small-strain deformation. The linear relation between the rupture force and the microinjector radius suggests that the embryo behaves as membrane-like when subjected to large-strain deformation. We also discuss the possible reasons causing the debate by analyzing the mechanical properties of F-actin filaments.
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Stratification analysis and case-control study of relationships between interleukin-6 gene polymorphisms and cervical cancer risk in a Chinese population.
Asian Pac. J. Cancer Prev.
PUBLISHED: 09-18-2014
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Interleukin-6 (IL-6), a central proinflammatory cytokine, maintains immune homeostasis and also plays important roles in cervical cancer. Therefore, we aimed to evaluate any associations of IL-6 gene polymorphisms at positions -174 and -572 with predisposition to cervical cancer in a Chinese population. The present hospital- based case-control study comprised 518 patients with cervical cancer and 518 healthy controls. Polymorphisms of the IL-6 gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Patients with cervical cancer had a significantly higher frequency of the IL-6 -174 CC genotype [odds ratio (OR) =1.52, 95% confidence interval (CI) = 1.06-2.19; p=0.02], IL-6 -572 CC genotype (OR =1.91, 95% CI = 1.16-3.13; p=0.01) and IL-6 -174 C allele (OR =1.21, 95% CI = 1.02-1.44; p=0.03) compared to healthy controls. When stratifying by the FIGO stage, patients with III-IV cervical cancer had a significantly higher frequency of IL-6 -174 CC genotype (OR =1.64, 95% CI =1.04-2.61; p=0.04). The CC genotypes of the IL-6 gene polymorphisms at positions -174 and -572 may confer a high risk of cervical cancer. Additional studies with detailed human papillomavirus (HPV) infection data are warranted to validate our findings.
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Smoking cessation in an urban population in China.
Am J Health Behav
PUBLISHED: 09-11-2014
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To examine smoking cessation among urban-based Chinese.
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High C4 gene copy numbers protects against Vogt-Koyanagi-Harada syndrome in Chinese Han.
Br J Ophthalmol
PUBLISHED: 09-02-2014
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Considering the phenotypical consequences and association of C4 copy number variation (CNV) with various autoimmune diseases, we aimed to examine C4 CNVs for 1027 patients with Vogt-Koyanagi-Harada (VKH) syndrome and 2083 controls.
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Oscillating gradient diffusion MRI reveals unique microstructural information in normal and hypoxia-ischemia injured mouse brains.
Magn Reson Med
PUBLISHED: 08-28-2014
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We investigated whether oscillating gradient diffusion MRI (dMRI) can provide information on brain microstructural changes after formaldehyde fixation and after hypoxic-ischemic (HI) injury beyond that provided by conventional dMRI.
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Mitochondrial genomes reveal the pattern and timing of marten (Martes), wolverine (Gulo), and fisher (Pekania) diversification.
Mol. Phylogenet. Evol.
PUBLISHED: 08-12-2014
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Despite recent advances in understanding the pattern and timescale of evolutionary diversification in the marten, wolverine, fisher, and tayra subfamily Guloninae (Mustelidae, Carnivora), several important issues still remain contentious. Among these are the phylogenetic position of Gulo relative to the subgenera of Martes (Martes and Charronia), the phylogenetic relationships within the subgenus Martes, and the timing of gulonine divergences. To elucidate these issues we explored nucleotide variation in 11 whole mitochondrial genomes (mitogenomes) from eight gulonine species and two outgroup meline species. Parsimony, maximum likelihood, and Bayesian phylogenetic analyses yielded fully resolved and identical patterns of relationships with high support for all divergences. The generic status of Pekania (P. pennanti), the monophyly of the genus Martes containing M. flavigula (subgenus Charronia) to the exclusion of the genus Gulo (G. gulo), and the M. foina (M. americana (M. melampus (M. zibellina, M. martes))) phylogeny of the subgenus Martes were strongly supported. Dating analyses (BEAST) using a set of five newly applied fossil calibrations provided divergence times considerably younger than previous multigene mitochondrial estimates, but similar to multigene nuclear and nuclear-mitochondrial estimates. The 95% confidence (highest posterior density) intervals of our divergence times fell within those inferred from nuclear and nuclear-mitochondrial sequence data, and were markedly narrower than in earlier studies (whether nuclear, mitochondrial, or combined). Notably, and contrary to long-held beliefs, our findings indicate that fossils older than the Tortonian-Messinian transition (late Late Miocene) do not represent Martes, excluding from this genus its putative members from the Early, Middle, and early Late Miocene. This study demonstrates the high informativeness of the mitogenome for phylogenetic inference and divergence time estimation within Guloninae, and suggests that mitogenomes can be highly informative also for other clades at similar levels of evolutionary divergence.
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Genome-wide association analysis of Vogt-Koyanagi-Harada syndrome identifies two new susceptibility loci at 1p31.2 and 10q21.3.
Nat. Genet.
PUBLISHED: 08-10-2014
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To identify new genetic risk factors for Vogt-Koyanagi-Harada (VKH) syndrome, we conducted a genome-wide association study of 2,208,258 SNPs in 774 cases and 2,009 controls with follow-up in a collection of 415 cases and 2,006 controls and a further collection of 349 cases and 1,588 controls from a Han Chinese population. We identified three loci associated with VKH syndrome susceptibility (IL23R-C1orf141, rs117633859, P(combined) = 3.42 × 10(-21), odds ratio (OR) = 1.82; ADO-ZNF365-EGR2, rs442309, P(combined) = 2.97 × 10(-11), OR = 1.37; and HLA-DRB1/DQA1, rs3021304, P(combined) = 1.26 × 10(-118), OR = 2.97). The five non-HLA genes were all expressed in human iris tissue. IL23R was also expressed in the ciliary body, and EGR2 was expressed in the ciliary body and choroid. The risk G allele of rs117633859 in the promoter region of IL23R exhibited low transcriptional activation in a cell-based reporter assay and was associated with diminished IL23R mRNA expression in human peripheral blood mononuclear cells.
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Effects of the steric hindrance of micropores in the hyper-cross-linked polymeric adsorbent on the adsorption of p-nitroaniline in aqueous solution.
J. Hazard. Mater.
PUBLISHED: 08-04-2014
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A hyper-cross-linked polymeric adsorbent with "--CH2--phenol--CH2--" as the cross-linked bridge (denoted GQ-05), and another hyper-cross-linked polymeric adsorbent with "--CH2--p-cresol--CH2--" as the cross-linked bridge (denoted GQ-03) were synthesized to reveal the effect of the steric hindrance of micropores in the hyper-cross-linked polymeric adsorbent on adsorption capacity and adsorption rate of p-nitroaniline (PNA) from aqueous solution. The results of adsorption kinetics indicated the order of the adsorption rate GQ-05>GQ-03. The pseudo-first-order rate equation could describe the entire adsorption process of PNA onto GQ-05 while the equation characterized the adsorption process of GQ-03 in two stages. The order of the adsorption capacity GQ-05>GQ-03 was demonstrated by thermodynamic analysis and dynamic adsorption. The steric hindrance of micropores in the hyper-cross-linked polymeric adsorbent was a crucial factor for the order of the adsorption capacity and adsorption rate.
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[AS-PCR assay for 20 mtDNA SNP typing and haplotype frequency].
Fa Yi Xue Za Zhi
PUBLISHED: 07-31-2014
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To develop a multiplex allele-specific PCR (AS-PCR) assay with three-color fluorescence labeling for mitochondrial DNA (mtDNA) SNP typing.
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Effects of cross-correlated noises on the transport of active Brownian particles.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 07-28-2014
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The transport properties of active Brownian particles driven by cross-correlated noises are investigated. Using the Langevin and Fokker-Planck approaches, the theoretical analysis of the model is presented. It is found that correlated noises can produce a net velocity, which stems from the symmetric breaking of the system induced by the correlation between noises. The mean velocity is negative for positive correlation but positive for negative correlation. The mean velocity increases while the effective diffusion decreases as the absolute value of the correlation between the noises increases. Both the mean velocity and the effective diffusion show a nonmonotonic dependence on the multiplicative noise, but a monotonically decreasing dependence on the additive noise.
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[Isotope compositions of elemental carbon in the smoke and ash from crop straw combustion].
Huan Jing Ke Xue
PUBLISHED: 07-25-2014
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Six genotypes of straws for rice, maize and wheat, respectively, were combusted under flaming and smoldering conditions, and the isotope compositions for elemental carbon ( EC) in the straw smoke and ash were investigated with an isotopic mass spectrometer. The results showed that the mean delta 13C values for EC in the flaming and smoldering smoke of rice straw were - 28. 3 per thousand and - 28.7 per thousand, with depletions of 2.7 per thousand and 3. 0 per thousand relative to that of total carbon (TC) in the straw, respectively. The mean delta 13C values for EC in the flaming and smoldering smoke of wheat straw were -28.5 per thousand and - 28. 0 per thousand, with a depletion of 0. 1 per thousand and enrichment of 0. 4 per thousand comparing to TC in the straw, respectively. The average values in two types of maize straw smoke were -17.2 per thousand and - 13. 6 per thousand,with a depletion of 3.4 per thousand and an enrichment of 0. 2 per thousand relative to TC in the straw, respectively. The mean delta 13C ratios for EC in the flaming and smoldering ash of rice straw were -27. 5 per thousand and -27. 3 per thousand, with depletions of 1.8 per thousand and 1. 6 per thousand comparing with TC in the straw, respectively. In the flaming and smoldering ash of wheat straw, the mean ratios were -27.4 per thousand and -26.0 per thousand, with enrichments of 0. 9 per thousand and 2. 4 per thousand relative to TC in the straw, respectively. In the two types of ash for maize straw, the average delta13 C values for EC were - 15. 0 per thousand and - 14. 8 per thousand,which were 1. 2 per thousand and 1.0 per thousand lighter than those of the straw TC. In general, evident isotope fractionations occur between EC in both smoke and ash and TC in the corresponding straws, especially for rice and maize straws. The isotopic ratios may be useful in identifying and estimating the contribution of EC from straw combustion to ambient aerosol.
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Paradoxical role of CBX8 in proliferation and metastasis of colorectal cancer.
Oncotarget
PUBLISHED: 07-23-2014
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The effect of polycomb chromobox (Cbx) proteins in cancer is context-dependent. The Chromobox homolog 8 (CBX8) was originally characterized as a transcriptional repressor, which inhibits cell proliferation in Ink4a-Arf-dependent and -independent manner. However, the role of CBX8 in colorectal cancer remains unknown. Here, we found that high CBX8 expression was associated with a low rate of distant metastasis and good prognosis in CRC patients, even though CBX8 was up-regulated in CRC cell lines and clinical samples. Knockdown of CBX8 inhibited CRC proliferation in vitro and in vivo, mostly by increasing p53 and its downstream effectors. However, knockdown of CBX8 enhanced CRC migration, invasion and metastasis in vitro and in vivo, in part through direct up-regulation of integrin ?4 (ITGB4) that in turn decreased RhoA activity. Collectively, the knockdown of CBX8 inhibited CRC proliferation, while promoting its metastasis, thus exerting paradoxical effects in CRC progression.
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P,N,N-pincer nickel-catalyzed cross-coupling of aryl fluorides and chlorides.
Org. Biomol. Chem.
PUBLISHED: 07-12-2014
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P,N,N-Pincer nickel complexes [Ni(Cl){N(2-R2PC6H4)(2'-Me2NC6H4)}] (R = Ph, 3a; R = Pr(i), 3b; R = Cy, 3c) were synthesized and their catalysis toward the Kumada or Negishi cross-coupling reaction of aryl fluorides and chlorides was evaluated. Complex 3a effectively catalyzes the cross-coupling of (hetero)aryl fluorides with aryl Grignard reagents at room temperature. Complex 3a also catalyzes the cross-coupling of (hetero)aryl chlorides and arylzinc reagents at 80 °C with low catalyst loadings and good functional group compatibility.
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Sensitive electrochemical detection of NADH and ethanol at low potential based on pyrocatechol violet electrodeposited on single walled carbon nanotubes-modified pencil graphite electrode.
Talanta
PUBLISHED: 07-03-2014
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In this work, the electrodeposition of pyrocatechol violet (PCV) was initially investigated by the electrochemical surface plasmon resonance (ESPR) technique. Subsequently, PCV was used as redox-mediator and was electrodeposited on the surface of pencil graphite electrode (PGE) modified with single-wall carbon nanotubes (SWCNTs). Owing to the remarkable synergistic effect of SWCNTs and PCV, PGE/SWCNTs/PCV exhibited excellent electrocatalytic activity towards dihydronicotinamide adenine dinucleotide (NADH) oxidation at low potential (0.2V vs. SCE) with fast amperometric response (<10s), broad linear range (1.3-280 ?M), good sensitivity (146.2 ?A mM(-1)cm(-2)) and low detection limit (1.3 ?M) at signal-to-noise ratio of 3. Thus, this PGE/SWCNTs/PCV could be further used to fabricate a sensitive and economic ethanol biosensor using alcohol dehydrogenase (ADH) via a glutaraldehyde/BSA cross-linking procedure.
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[Performance-intensity function of short Mandarin monosyllabic word list for normal-hearing listeners].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 06-26-2014
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To analyze the short monosyllabic list of Mandarin speech test materials (MSTMs) which have been evaluated the equivalence of difficulty, and to establish the performance-intensity function (P-I function) for people with normal hearing as clinical reference of hearing recovery and individuals ability to perceive and process speech.
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[A review of multi-scale studies on spatial variation of the lead (Pb) concentration in urban soils].
Huan Jing Ke Xue
PUBLISHED: 06-21-2014
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The accumulation of Pb in urban soils is still apparent in China, and scientific assessment and management of risks from Pb-contaminated soils is necessarily based on contamination levels and extent evaluated accurately. Lead concentration in urban soils has a strong spatial variation and complex spatial structures. Carried out in a single spatial scale, most current investigations cannot comprehensively reveal characteristics of spatial structures, and did not promote more scientific assessment and management of risk. Exploring a new method which can help identify the overall spatial structures is needed. To achieve this aim, this paper firstly investigated the factors linked to the spatial variability of Pb concentration in urban soils, and three major factors were identified: various pollution sources, hierarchical pollution processes and heterogeneous urban landscape. These factors were form a nested hierarchical spatial structure with three spatial levels. Based on the conceptual spatial structure, we proposed a method framework guided by geostatistical theory and focused on linear mixed model (LMM). This proposed framework can divide the nested hierarchical spatial structures of Pb concentration in urban soils into three levels: global trend, random variation with spatial autocorrelation, and outliers. Two recommendations were given to promote the multiple-scale investigation in spatial variation of soil Pb contamination in urban area including: finding more efficient sampling strategy and determining the characteristic scale.
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An electrochemical immunosensor for ultrasensitive detection of carbohydrate antigen 199 based on Au@Cu(x)OS yolk-shell nanostructures with porous shells as labels.
Biosens Bioelectron
PUBLISHED: 06-18-2014
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A novel and sensitive electrochemical immunosensor for ultrasensitive detection of pancreatic cancer biomarker carbohydrate antigen 199 (CA199) was proposed by using Au@Cu(x)OS yolk-shell nanostructures with porous shells as labels for signal amplification. Au@Cu(x)OS yolk-shell nanostructures exhibit high electrocatalytic activity toward the reduction of hydrogen peroxide (H2O2) as analytical signal. Moreover, secondary antibody (Ab2) can adsorb on the surface of Au@Cu(x)OS with porous shells which has large surface area and could greatly increase the probability of Ab2-antigen interactions thereby leading to higher sensitivity. Reduced graphene oxide-tetraethylene pentamine (rGO-TEPA), containing abundant amine groups, was supported Au nanoparticles as a support platform to immobilize the primary antibody (Ab1). The resulting sensing interface of rGO-TEPA/AuNPs could provide a large electroconductive surface area, allowing high loadings of the biological recognition elements as well as the occurrence of electrocatalytic and electron-transfer processes. Under optimal conditions, the immunosensor exhibited a wide linear response to CA199 ranging from 0.001 to 12 U/mL with a low detection limit of 0.0005 U/mL. The designed immunosensor displayed good precision, high sensitivity, acceptable stability and reproducibility, and has been applied to the analysis of serum with satisfactory results. The proposed method provides a new promising platform of clinical immunoassay for other biomolecules.
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Molecular cloning and characterization of cathepsin L from freshwater mussel, Cristaria plicata.
Fish Shellfish Immunol.
PUBLISHED: 06-11-2014
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Cathepsin L is one of the crucial enzyme superfamilies and involved in the immune responses. The Cathepsin L cDNA and genome of Cristaria plicata?CpCL? was cloned from the hemocytes using degenerate primers by the rapid amplification of cDNA ends (RACE) PCR. The genomic DNA was 9353 bp long and had a total of six introns and seven exons. The full-length cDNA of CpCL was 1144 bp, the cDNA contained a 5' untranslated region (UTR) of 34 nucleotides, the 3' UTR of 108 bp with a canonical polyadenylation signal sequence AATAAA and a polyA tail, and an open reading frame (ORF) of 1002 bp, encoding 333 amino acid residues with 37.65 kDa predicted molecular weight. The theoretical isoelectric point was 8.61. The prepro-cathepsin L was consisted of a typical signal peptide (Met1-Gly20), a pro-region peptide (Leu21-Glu116) and a mature peptide (Tyr117-Val333). Many members of the papain family possessed of a proline residue at position 2 in the mature enzymem, this was also observed in CpCL. The preproprotein included an oxyanion hole (Gln 135), the active center formed by Cys141, His280 and Asn 300, the potential N-glycosylation site (Asn38, Asn 113 and Asn 272) and the conserved GCXGG motifs, which was characteristic of cathepsin, the conserved ERWNIN and GNFD motifs, which were characteristic for cathepsin L. Homology analysis revealed that the CpCL shared 49-87% identity to other known cathepsin L sequences. The phylogenetic tree showed that the CpCL clustered with the invertebrate cathepsin L cysteine proteases, and was closely related to the cathepsin L of Hyriopsis cumingii. The expression of CpCL mRNA was detected in hepatopancreas, hemocytes, mantle, gills and adductor muscle, and the higher expression level was in hepatopancreas. After A. hydrophila stimulation, the expression of the CpCL mRNA was up-regulated in hemocytes and hepatopancreas, and the expression level was significantly lower in gill than one after PBS challenge group.
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A Meta-Analysis on the Relations between EGFR R521K Polymorphism and Risk of Cancer.
Int J Genomics
PUBLISHED: 06-07-2014
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The EGFR R521K polymorphism has been shown to reduce the activity of EGFR; however, the association between EGFR R521K polymorphism and the risk of cancer remains inconclusive; therefore we performed a meta-analysis to evaluate the relationship between EGFR R521K polymorphism and susceptibility to cancer. Our results suggest that the EGFR R521K polymorphism is not associated with risk of cancer, but the different chemosensitivity to anticancer drugs may need further investigation.
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Design, synthesis, crystal structure, insecticidal activity, molecular docking, and QSAR studies of novel N3-substituted imidacloprid derivatives.
J. Agric. Food Chem.
PUBLISHED: 06-06-2014
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Three novel series of N3-substituted imidacloprid derivatives were designed and synthesized, and their structures were identified on the basis of satisfactory analytical and spectral ((1)H NMR, (13)C NMR, MS, elemental analysis, and X-ray) data. Preliminary bioassays indicated that all of the derivatives exhibited significant insecticidal activities against Aphis craccivora, with LC50 values ranging from 0.00895 to 0.49947 mmol/L, and the insecticidal activities of some of them were comparable to those of the control imidacloprid. Some key structural features related to their insecticidal activities were identified, and the binding modes between target compounds and nAChR model were also further explored by molecular docking. By comparing the interaction features of imidacloprid and compound 26 with highest insecticidal activity, the origin of the high insecticidal activity of compound 26 was identified. On the basis of the conformations generated by molecular docking, a satisfactory 2D-QSAR model with six selected descriptors was built using genetic algorithm-multiple linear regression (GA-MLR) method. The analysis of the built model showed the molecular size, shape, and the ability to form hydrogen bond were important for insecticidal potency. The information obtained in the study will be very helpful for the design of new derivatives with high insecticidal activities.
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[Chemical compositions of n-alkanols in smoke from rice and maize straw combustion].
Huan Jing Ke Xue
PUBLISHED: 06-03-2014
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Six genotypes of rice straw and four genotypes of maize straw were burned under different conditions, and the smoke was collected and n-alkanol in it was measured by GC-MS. Results showed that, in the smoke from rice straw flaming combustion, n-alkanol was composed of individual compounds from C14 to C34, and total contents(sigma) changed in the range of 1 604.4 to 13 889.7 mg x kg(-1). The ratio values of amount for n-alkanol with lower carbon number to that for one with higher carbon number (L/H) were in the range of 0.02 to 0.09. The values for C24/C30, C32/C30, C30/sigma, CPI, and ACL varied from 3.3% to 19.6%, 8.4% to 19.9%, 53.9% to 72.6%, 8.7 to 21.5, and 29.0 to 30.1, respectively. The abundance distribution for the compounds was bimodal with the maximal and the second peaks at C30 and C24, respectively. In smoldering smoke of rice straw, individual n-alkanol from C14 to C34 were also analyzed, with sigma values varying in the range of 1 688.7 to 5 168.2 mg x kg(-1). The ratios for L/H, C24/C30, C32/ C30, and C30/sigma ranged from 0.08 to 0.14, 31.0% to 70.5%, 6.9% to 17.6%, 39.5% to 57.8%, respectively. In addition, the CPI and ACL values varied from 10.7 to 17. 5, and 27.2 to 28.5, respectively. Moreover, the distribution pattern was similar to that in flaming smoke. In flaming smoke of maize straw, n-alkanol from C12 to C34 were identified, with sigma values being in the range of 852.3 to 2 667.9 mg x kg(-1). The values for L/H, C24/C28, C32/C28, C28/sigma, CPI, and ACL varied from 0.2 to 1.0, 104.3% to 293.3%, 42.2% to 61.4%, 7.3% to 16.5%, 5.6 to 9.7, and 23.1 to 26.9, respectively. Besides, the abundance distribution pattern was mainly bimodal with a maximal peak at C30, C24 or C22. In the smoldering smoke for maize straw, the same individual n-alkanols were found, and the sigma values changed from 1493.0 to 8386.9 mg x kg(-1). The values for L/H, C24/C28, C32/C28, C28/sigma, CPI and ACL were in the range of 0.2 to 0.3, 53.6% to 217.6%, 21.7% to 75.9%, 8.8% to 27.3%, 4.2 to 6.5, and 26.3 to 27.2, respectively. Furthermore, the distribution pattern was bimodal as well with the highest peak mainly at C30 and the second one at C24. In brief, obvious discrimination exists among chemical compositions of n-alkanol in the straw and smoke. C24/C30, C32/C30, and C30/sigma are useful proxies in distinguishing between n-alkanol in airborne aerosol deriving from rice straw and one released in rice straw combustion process. L/H, C24/C28, C32/C28, and C28/sigma may have a potential in discriminating the compounds from maize straw and its burning. L/H is possibly used to makea distinction between the organic compounds from rice and maize straws, and/or from combustion of the straws.
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Correlation of fatigue during the acute stage of stroke with serum uric Acid and glucose levels, depression, and disability.
Eur. Neurol.
PUBLISHED: 05-27-2014
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To clarify the correlation of fatigue during the acute stage of stroke with serum uric acid (UA) and glucose levels, depression, and disability.
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Targeting the anaphase-promoting complex/cyclosome (APC/C)- bromodomain containing 7 (BRD7) pathway for human osteosarcoma.
Oncotarget
PUBLISHED: 05-21-2014
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Osteosarcoma is the most common primary malignant bone tumor in childhood and adolescence and has a propensity for local invasion and early lung metastasis. However, the current therapies often result in chemoresistance, and a therapeutic target is not available in the clinic for osteosarcoma. Here, we report that BRD7 forms a complex with the anaphase-promoting complex/cyclosome (APC/C) and is degraded by APC/C(cdh1) and APC/C(cdc20) during the cell cycle. Moreover, BRD7 is a tumor suppressor in osteosarcoma, and the BRD7 mutant resistant to degradation by APC/C is more efficient than the wild-type protein at suppressing proliferation, colony formation, and tumor growth of osteosarcoma in vitro and in vivo. The combination of proTAME, an inhibitor of APC/C, with chemotherapeutic drugs efficiently targets osteosarcoma in vitro. Furthermore, there is a strong inverse correlation of protein levels between BRD7 and Cdh1 or Cdc20, and lower BRD7 expression is an indicator for poor prognosis in patients with osteosarcoma. Collectively, our results indicate that targeting the APC/C-BRD7 pathway may be a novel strategy for treating osteosarcoma.
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Prenatal diagnosis of Down syndrome using cell-free fetal DNA in amniotic fluid by quantitative fluorescent polymersase chain reaction.
Chin. Med. J.
PUBLISHED: 05-15-2014
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Amniotic fluid (AF) supernatant contains cell-free fetal DNA (cffDNA) fragments. This study attempted to take advantage of cffDNA as a new material for prenatal diagnosis, which could be combined with simple quantitative fluorescent polymerase chain reaction (QF-PCR) to provide an ancillary method for the prenatal diagnosis of trisomy 21 syndrome.
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Design and synthesis of new 7-(N-substituted-methyl)-camptothecin derivatives as potent cytotoxic agents.
Bioorg. Med. Chem. Lett.
PUBLISHED: 05-09-2014
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A series of novel 7-(N-substituted-methyl)-camptothecin derivatives was designed, synthesized, and evaluated for in vitro cytotoxicity against four human tumor cell lines, A-549, MDA-MB-231, KB, and KBvin. All of the derivatives showed promising in vitro cytotoxic activity against the tested tumor cell lines, with IC50 values ranging from 0.0023 to 1.11 ?M, and were as or more potent than topotecan. Compounds 9d, 9e, and 9r exhibited the highest antiproliferative activity among all prepared derivatives. Furthermore, all of the compounds were more potent than paclitaxel against the multidrug-resistant (MDR) KBvin subline. With a concise efficient synthesis and potent cytotoxic profiles, especially significant activity towards KBvin, compounds 9d, 9e, and 9r merit further development as a new generation of camptothecin-derived anticancer clinical trial candidates.
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[Establishment of the multiplex genotyping system for 16 SNP loci on mtDNA].
Fa Yi Xue Za Zhi
PUBLISHED: 05-09-2014
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To establish a multiplex genotyping system of mtDNA SNP.
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Role of calmodulin in thermotolerance.
Plant Signal Behav
PUBLISHED: 05-01-2014
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Nitric oxide (NO) and hydrogen peroxide (H 2O 2) are 2 key elements in heat shock (HS) signaling pathway. Our experiments indicate the existence of a cross talk among H 2O 2, NO, Ca (2+) channels, and the activation of calmodulin (CaM) to stimulate the DNA-binding activity of HS transcription factors as well as the accumulation of HS proteins so as to confer thermotolerance. CaM can bind to target proteins to alter their function, acting as part of a calcium signal transduction pathway. However, only a few of its target proteins had been reported by now. Herein we are discussing them and conclude that in order to obtain a more profound understanding of CaM signaling, further research will be needed in the future.
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A numerical study of heat and water vapor transfer in MDCT-based human airway models.
Ann Biomed Eng
PUBLISHED: 04-11-2014
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A three-dimensional (3D) thermo-fluid model is developed to study regional distributions of temperature and water vapor in three multi-detector row computed-tomography-based human airways with minute ventilations of 6, 15 and 30 L/min. A one-dimensional (1D) model is also solved to provide necessary initial and boundary conditions for the 3D model. Both 3D and 1D predicted temperature distributions agree well with available in vivo measurement data. On inspiration, the 3D cold high-speed air stream is split at the bifurcation to form secondary flows, with its cold regions biased toward the inner wall. The cold air flowing along the wall is warmed up more rapidly than the air in the lumen center. The repeated splitting pattern of air streams caused by bifurcations acts as an effective mechanism for rapid heat and mass transfer in 3D. This provides a key difference from the 1D model, where heating relies largely on diffusion in the radial direction, thus significantly affecting gradient-dependent variables, such as energy flux and water loss rate. We then propose the correlations for respective heat and mass transfer in the airways of up to 6 generations: [Formula: see text] and [Formula: see text], where Nu is the Nusselt number, Sh is the Sherwood number, Re is the branch Reynolds number, D a is the airway equivalent diameter, and [Formula: see text] is the tracheal equivalent diameter.
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Anaerobic digestion of corn stovers for methane production in a novel bionic reactor.
Bioresour. Technol.
PUBLISHED: 04-05-2014
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To improve the biogas production from corn stovers, a new bionic reactor was designed and constructed. The bionic reactor simulated the rumen digestion of ruminants. The liquid was separated from corn stovers and refluxed into corn stovers again, which simulated the undigested particles separated from completely digested materials and fed back again for further degradation in ruminant stomach. Results showed that the bionic reactor was effective for anaerobic digestion of corn stovers. The liquid amount and its reflux showed an obvious positive correlation with biogas production. The highest biogas production rate was 21.6 ml/gVS-addedd, and the total cumulative biogas production was 256.5 ml/gVS-added. The methane content in biogas ranged from 52.2% to 63.3%. The degradation of corn stovers were greatly enhanced through simulating the animal digestion mechanisms in this bionic reactor.
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Ultrasensitive enzyme-free immunoassay for squamous cell carcinoma antigen using carbon supported Pd-Au as electrocatalytic labels.
Anal. Chim. Acta
PUBLISHED: 04-03-2014
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A novel nonenzymatic sandwich-type electrochemical immunosensor has been developed to detect squamous cell carcinoma antigen (SCCA). Nitrogen-doped graphene sheet (N-GS) was used to increase capacity of capturing primary antibodies (Ab1). Carbon-supported Pd-Au binary nanoparticles (Pd-Au/C) were synthesized and used to label secondary antibodies (Ab2). The specific binding of SCCA and antibodies enabled a quantitative attachment of Pd-Au/C on the electrode surface. Electrocatalytic analysis showed that the prepared Pd-Au/C exhibit excellent electrocatalytic activity towards hydrogen peroxide (H2O2). We use current response of electrocatalytic labels Pd-Au/C to detect the concentration of SCCA. The unique nonenzymatic immunosensor exhibits a relatively wide linear range from 0.005 to 2 ng mL(-1) and high sensitivity with a low detection limit of 1.7 pg mL(-1). The immunsensor also shows good reproducibility (4.2%) and stability (5.8%), which makes it an enormous application prospect in clinical research.
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Chemerin C9 peptide induces receptor internalization through a clathrin-independent pathway.
Acta Pharmacol. Sin.
PUBLISHED: 03-24-2014
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The chemerin receptor CMKLR1 is one type of G protein-coupled receptors abundant in monocyte-derived dendritic cells and macrophages, which plays a key role in the entry of a subset of immunodeficiency viruses including HIV/SIV into lymphocytes and macrophages. The aim of this work was to investigate how CMKLR1 was internalized and whether its internalization affected cell signaling in vitro.
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A novel multi-amplification photoelectrochemical immunoassay based on copper(II) enhanced polythiophene sensitized graphitic carbon nitride nanosheet.
Biosens Bioelectron
PUBLISHED: 03-14-2014
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A new sandwich photoelectrochemical (PEC) sensing strategy was proposed for the first time based on the increasing photocurrent of water-soluble polythiophene sensitized g-C3N4 nanosheet (PT-Cl/g-C3N4) in the presence of copper(II) (Cu(2+)), which was doped on the surface of titanium dioxide as labels for multi-amplification. Herein, the photoactive films of PT-Cl/g-C3N4 is employed as the photoactive antibody (Ab1) immobilization matrix for the subsequent sandwich-type antibody-antigen affinity interactions. Upon the presence of antigen (Ag), greatly enhanced photocurrent could be triggered in the PEC platform by the labels of second antibody (Ab2) of Cu(2+) doped titanium dioxide (Cu(2+)-TiO2). As a result of the multi-amplification in this Cu(2+)-TiO2 enhanced PT-Cl/g-C3N4-based PEC immunoassay, it possesses excellent analytical performance. The antigen could be detected from 0.01 pg mL(-1) to 100.0 ng mL(-1) with a detection limit of 5 fg mL(-1). This work opens up g-C3N4 nanosheet applied in PEC sensing. More importantly, the strategy of specific positive effect of Cu(2+) on the photocurrent of g-C3N4 opens an alternative horizon for PEC sensing.
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Limit cycle analysis of active disturbance rejection control system with two nonlinearities.
ISA Trans
PUBLISHED: 03-03-2014
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Introduction of nonlinearities to active disturbance rejection control algorithm might have high control efficiency in some situations, but makes the systems with complex nonlinearity. Limit cycle is a typical phenomenon that can be observed in the nonlinear systems, usually causing failure or danger of the systems. This paper approaches the problem of the existence of limit cycles of a second-order fast tool servo system using active disturbance rejection control algorithm with two fal nonlinearities. A frequency domain approach is presented by using describing function technique and transfer function representation to characterize the nonlinear system. The derivations of the describing functions for fal nonlinearities and treatment of two nonlinearities connected in series are given to facilitate the limit cycles analysis. The effects of the parameters of both the nonlinearity and the controller on the limit cycles are presented, indicating that the limit cycles caused by the nonlinearities can be easily suppressed if the parameters are chosen carefully. Simulations in the time domain are performed to assess the prediction accuracy based on the describing function.
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Individual patterns of alcohol use.
Addict Behav
PUBLISHED: 02-27-2014
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We present methodology to identify statistically distinct patterns of daily alcohol use and classify them into categories that could be further used in monitoring of transitions between patterns such as transitions from regular to problem use.
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Preparation of Au-Pt nanostructures by combining top-down with bottom-up strategies and application in label-free electrochemical immunosensor for detection of NMP22.
Bioelectrochemistry
PUBLISHED: 02-20-2014
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A novel label-free amperometric immunosensor for sensitive detection of nuclear matrix protein 22 (NMP22) was developed based on Au-Pt bimetallic nanostructures, which were prepared by combining top-down with bottom-up strategies. Nanoporous gold (NPG) was prepared by "top-down" dealloying of commercial Au/Ag alloy film. After deposition of NPG on an electrode, Pt nanoparticles (PtNPs) were further decorated on NPG by "bottom-up" electrodeposition. The prepared bimetallic nanostructures combine the merits of both NPG and PtNPs, and show a high electrocatalytic activity towards the reduction of H2O2. The label-free immunosensor was constructed by directly immobilizing antibody of NMP22 (anti-NMP22) on the surface of bimetallic nanostructures. The immunoreaction induced amperometric response could be detected and negatively correlated to the concentration of NMP22. Bimetallic nanostructure morphologies and detection conditions were investigated to obtain the best sensing performance. Under the optimal conditions, a linear range from 0.01ng/mL to 10ng/mL and a detection limit of 3.33pg/mL were obtained. The proposed immunosensor showed high sensitivity, good selectivity, stability, reproducibility, and regeneration for the detection of NMP22, and it was evaluated in urine samples, receiving satisfactory results.
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Salidroside stimulates mitochondrial biogenesis and protects against H?O?-induced endothelial dysfunction.
Oxid Med Cell Longev
PUBLISHED: 02-13-2014
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Salidroside (SAL) is an active component of Rhodiola rosea with documented antioxidative properties. The purpose of this study is to explore the mechanism of the protective effect of SAL on hydrogen peroxide- (H2O2-) induced endothelial dysfunction. Pretreatment of the human umbilical vein endothelial cells (HUVECs) with SAL significantly reduced the cytotoxicity brought by H2O2. Functional studies on the rat aortas found that SAL rescued the endothelium-dependent relaxation and reduced superoxide anion (O2(?-)) production induced by H2O2. Meanwhile, SAL pretreatment inhibited H2O2-induced nitric oxide (NO) production. The underlying mechanisms involve the inhibition of H2O2-induced activation of endothelial nitric oxide synthase (eNOS), adenosine monophosphate-activated protein kinase (AMPK), and Akt, as well as the redox sensitive transcription factor, NF-kappa B (NF- ? B). SAL also increased mitochondrial mass and upregulated the mitochondrial biogenesis factors, peroxisome proliferator-activated receptor gamma-coactivator-1alpha (PGC-1 ? ), and mitochondrial transcription factor A (TFAM) in the endothelial cells. H2O2-induced mitochondrial dysfunction, as demonstrated by reduced mitochondrial membrane potential (? ? m) and ATP production, was rescued by SAL pretreatment. Taken together, these findings implicate that SAL could protect endothelium against H2O2-induced injury via promoting mitochondrial biogenesis and function, thus preventing the overactivation of oxidative stress-related downstream signaling pathways.
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Atrial fibrillation in patients with gastroesophageal reflux disease: a comprehensive review.
World J. Gastroenterol.
PUBLISHED: 02-09-2014
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To analyze the potential relationship between gastroesophageal reflux disease (GERD) and the development of atrial fibrillation (AF).
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Biosensing platform based on graphene oxide via self-assembly induced by synergic interactions.
Anal. Biochem.
PUBLISHED: 02-08-2014
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A novel self-assembled glucose biosensor based on graphene oxide (GO) was constructed by using 1-pyrenebutyric acid-N-hydroxysuccinimide ester (PANHS) as linking molecular. The stepwise self-assembly process was performed for PANHS anchoring in N,N-dimethylformamide (DMF) solvent and the further glucose oxidase (GOD) binding in aqueous solution, respectively. The molecular interactions and the morphologic properties were characterized by Fourier transform infrared spectroscopy (FTIR), field emission scanning electronic microscopy (FESEM), and atomic force microscopy (AFM). In addition, the quantitative loadings of anchored PANHS and GOD were well elucidated by surface plasmon resonance (SPR) measurements. The obtained novel glucose sensor exhibited satisfactory analytical performance to glucose: wide linear range (4.0×10(-6) to 4.4×10(-3) M), fast response (10s), high sensitivity (40.5±0.4 mA M(-1) cm(-2)), and low detection limit (2 ?M, S/N=3). Furthermore, the biosensor exhibited excellent long-term stability and satisfactory reproducibility.
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Anti-Inflammatory Effects of the Bioactive Compound Ferulic Acid Contained in Oldenlandia diffusa on Collagen-Induced Arthritis in Rats.
Evid Based Complement Alternat Med
PUBLISHED: 01-22-2014
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Objectives. This study aimed to identify the active compounds in Oldenlandia diffusa (OD) decoction and the compounds absorbed into plasma, and to determine whether the absorbed compounds derived from OD exerted any anti-inflammatory effects in rats with collagen induced arthritis (CIA). Methods. The UPLC-PDA (Ultra Performance Liquid Chromatography Photo-Diode Array) method was applied to identify the active compounds both in the decoction and rat plasma. The absorbable compound was administered to the CIA rats, and the effects were dynamically observed. X-ray films of the joints and HE stain of synovial tissues were analyzed. The levels of IL-1 ? and TNF- ? in the rats from each group were measured by means of ELISA. The absorbed compound in the plasma of CIA rats was identified as ferulic acid (FA), following OD decoction administration. Two weeks after the administration of FA solution or OD decoction, the general conditions improved compared to the model group. The anti-inflammatory effect of FA was inferior to that of the OD decoction (P < 0.05), based on a comparison of IL-1 ? TNF- ? levels. FA from the OD decoction was absorbed into the body of CIA rats, where it elicited anti-inflammatory responses in rats with CIA. Conclusions. These results suggest that FA is the bioactive compound in OD decoction, and FA exerts its effects through anti-inflammatory pathways.
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Cathodic electrochemiluminescence immunosensor based on nanocomposites of semiconductor carboxylated g-C3N4 and graphene for the ultrasensitive detection of squamous cell carcinoma antigen.
Biosens Bioelectron
PUBLISHED: 01-14-2014
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A novel label-free electrochemiluminescence (ECL) immunosensor was developed for the detection of squamous cell carcinoma antigen (SCCA) based on nanocomposites of semiconductor carboxylated graphitic carbon nitride (g-C3N4) and graphene (g-C3N4-graphene). The ECL intensity of carboxylated g-C3N4 was much enhanced after being combined with graphene which had excellent electron-transfer ability. The sensing platform was constructed by depositing g-C3N4-graphene on electrodes and immobilizing antibodies on the surface of carboxylated g-C3N4 through amidation. The specific immunoreaction between SCCA and antibody resulted in the decrease of ECL intensity and the intensity decreased linearly with the logarithm of SCCA concentration in the range of 0.025-10 ng mL(-1) with a detection limit of 8.53 pg mL(-1). The developed ECL immunosensor exhibited high sensitivity, good reproducibility and long-term stability, which possessed great potential for cancer detection in clinical laboratory diagnosis.
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Abnormal partitioning of hexokinase 1 suggests disruption of a glutamate transport protein complex in schizophrenia.
Schizophr. Res.
PUBLISHED: 01-13-2014
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Excitatory amino acid transporter 2 (EAAT2) belongs to a family of Na(+) dependent glutamate transporters that maintain a low synaptic concentration of glutamate by removing glutamate from the synaptic cleft into astroglia and neurons. EAAT2 activity depends on Na(+) and K(+) gradients generated by Na(+)/K(+) ATPase and ATP. Hexokinase 1 (HK1), an initial enzyme of glycolysis, binds to mitochondrial outer membrane where it couples cytosolic glycolysis to mitochondrial oxidative phosphorylation, producing ATP utilized by the EAAT2/Na(+)/K(+) ATPase protein complex to facilitate glutamate reuptake. In this study, we hypothesized that the protein complex formed by EAAT2, Na(+)/K(+) ATPase and mitochondrial proteins in human postmortem prefrontal cortex may be disrupted, leading to abnormal glutamate transmission in schizophrenia. We first determined that EAAT2, Na(+)/K(+) ATPase, HK1 and aconitase were found in both EAAT2 and Na(+)/K(+) ATPase interactomes by immunoisolation and mass spectrometry in human postmortem prefrontal cortex. Next, we measured levels of glutamate transport complex proteins in subcellular fractions in the dorsolateral prefrontal cortex and found increases in the EAAT2B isoform of EAAT2 in a fraction containing extrasynaptic membranes and increased aconitase 1 in a mitochondrial fraction. Finally, an increased ratio of HK1 protein in the extrasynaptic membrane/mitochondrial fraction was found in subjects with schizophrenia, suggesting that HK1 protein is abnormally partitioned in this illness. Our findings indicate that the integrity of the glutamate transport protein complex may be disrupted, leading to decreased perisynaptic buffering and reuptake of glutamate, as well as impaired energy metabolism in schizophrenia.
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Sensitisation of human lung adenocarcinoma A549 cells to radiotherapy by Nimotuzumab is associated with enhanced apoptosis and cell cycle arrest in the G2/M phase.
Cell Biol. Int.
PUBLISHED: 01-02-2014
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The epidermal growth factor receptor (EGFR) plays an important role in tumorigenesis and maintenance of cancers, making it a possible therapeutic target for cancer treatment. Nimotuzumab (h-R3), a humanised monoclonal antibody against EGFR, sensitises human lung adenocarcinoma A549 cells to radiotherapy. We have investigated the underlying molecular mechanism by treating A549 cells with Nimotuzumab (100??g/mL) alone or in combination with a single dose of 2?Gy irradiation, and analysing apoptosis and cell cycle distribution by flow cytometry. Nimotuzumab significantly enhanced radiation-induced apoptosis of A549 cells as evidenced by increased cell apoptosis (7.15?±?0.30%) compared with the control group (1.08?±?0.25%), Nimotuzumab alone group (4.89?±?0.30%) and irradiation alone group (5.90?±?0.15%). Combining Nimotuzumab with irradiation significantly arrested cells in the G2/M phase (43.?±?0.36%) compared radiotherapy alone (18.7?±?0.35%) and single Nimotuzumab treatment (27.2?±?0.17%). A combination of Nimotuzumab with radiation increased apoptosis and G2/M phase arrest in human lung adenocarcinoma A549 cells, suggesting potential development of combinatorial therapy of Nimotuzumab with radiotherapy for lung cancer.
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Cyclin D1 G870A Polymorphism and Risk of Nasopharyngeal Carcinoma: A Case-Control Study and Meta-Analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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Cyclin D1 (CCND1) plays a key role in cell cycle regulation. It is a well-established human oncogene which is frequently amplified or overexpressed in cancers. The association between CCND1 G870A polymorphism and cancer risk has been widely assessed. However, a definitive conclusion between CCND1 G870A polymorphism and risk of nasopharyngeal carcinoma (NPC) remains elusive.
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The relationship between irritable bowel syndrome and psychiatric disorders: from molecular changes to clinical manifestations.
J Mol Psychiatry
PUBLISHED: 01-01-2014
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Irritable bowel syndrome (IBS) is a functional syndrome characterized by chronic abdominal pain accompanied by altered bowel habits. Although generally considered a functional disorder, there is now substantial evidence that IBS is associated with a poor quality of life and significant negative impact on work and social domains. Neuroimaging studies documented changes in the prefrontal cortex, ventro-lateral and posterior parietal cortex and thalami, and implicate alteration of brain circuits involved in attention, emotion and pain modulation. Emerging data reveals the interaction between psychiatric disorders including generalized anxiety disorder, panic disorder, major depressive disorder, bipolar disorder, and schizophrenia and IBS, which suggests that this association should not be ignored when developing strategies for screening and treatment. Psychological, social and genetic factors appear to be important in the development of IBS symptomatology through several mechanisms: alteration of HPA axis modulation, enhanced perception of visceral stimuli or psychological vulnerability. Elucidating the molecular mechanisms of IBS with or without psychiatric comorbidities is crucial for elucidating the pathophysiology and for the identification of new therapeutical targets in IBS.
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CD117 Expression in Fibroblasts-Like Stromal Cells Indicates Unfavorable Clinical Outcomes in Ovarian Carcinoma Patients.
PLoS ONE
PUBLISHED: 01-01-2014
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The stem cell factor (SCF) receptor CD117 (c-kit), is widely used for identification of hematopoietic stem cells and cancer stem cells. Moreover, CD117 expression in carcinoma cells indicates a poor prognosis in a variety of cancers. However the potential expression in tumor microenvironment and the biological and clinical impact are currently not reported. The expression of CD117 was immunohistochemically evaluated in a serial of 242 epithelial ovarian cancer (EOC) cases. Thirty-eight out of 242 cases were CD117 positive in fibroblast-like stromal cells and 22 cases were positive in EOC cells. Four cases were both positive in fibroblast-like stromal cells and EOC cells for CD117. CD117 expression in fibroblast-like stromal cells in ovarian carcinoma was closely linked to advanced FIGO stage, poor differentiation grade and histological subtype (p<0.05), and it was significantly associated with poor overall survival (OS) and progression free survival (PFS) (Kaplan-Meier analysis; p<0.05, log-rank test). CD117 expression in ovarian carcinoma cells was not associated with these clinicopathological variables. The CD117 positive fibroblast-like stromal cells were all positive for mesenchymal stem/stromal cell (MSC) marker CD73 but negative for fibroblast markers fibroblast activation protein (FAP) and ? smooth muscle actin (?-SMA), indicating that the CD117+/CD73+ fibroblast-like stromal cells are a subtype of mesenchymal stem cells in tumor stroma, although further characterization of these cells are needed. It is concluded herewith that the presence of CD117+/CD73+ fibroblast-like stromal cells in ovarian carcinoma is an unfavorable clinical outcome indication.
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Female Specific Association between NNMT Gene and Schizophrenia in a Han Chinese population.
Int J Med Sci
PUBLISHED: 01-01-2014
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Accumulating evidence has shown that alterations in one carbon metabolism might play an important role in the pathogenesis of schizophrenia (SZ). Nicotinamide-N-methyltransferase (NNMT) is one of the key enzymes of one-carbon metabolism. To examine whether NNMT gene was associated with SZ in Han Chinese population, we selected seven single nucleotide polymorphisms (SNPs) in NNMT gene, and investigated its association with SZ from a cohort of 42 SZ patients and 86 healthy controls by Mass-ARRAY technology. Statistical analyses revealed that one (rs694539) of the SNPs in the female subgroup showed significant difference between SZ patients and controls both in genotypic (p= 0.0170) and allelic frequencies (p = 0.0059). We also found that the frequency of haplotype 'A G G C T C T' in the female patients was significantly higher than in controls (p=0.0015). Our results suggest that NNMT rs694539 may have a role in the etiology of SZ in a Han Chinese female population.
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A functional variant of PTPN22 confers risk for Vogt-Koyanagi-Harada syndrome but not for ankylosing spondylitis.
PLoS ONE
PUBLISHED: 01-01-2014
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Protein tyrosine phosphatase non-receptor 22 (PTPN22) is a key negative regulator of T lymphocytes and has emerged as an important candidate susceptibility factor for a number of immune-related diseases. This study aimed to examine the predisposition of PTPN22 SNPs to Vogt-Koyanagi-Harada (VKH) syndrome and acute anterior uveitis (AAU) associated with ankylosing spondylitis (AS).
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The Role of Superoxide Dismutase in the Survival of Mycobacterium tuberculosis in Macrophages.
Jpn. J. Infect. Dis.
PUBLISHED: 11-26-2013
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There is a large amount of information available regarding the chemical structure and biological activity of superoxide dismutase (SOD), which is abundantly generated by Mycobacterium tuberculosis in the early stages of growth. SOD is a strong superoxide radical scavenger, which plays a significant role in resisting oxidative stress. On the other hand, SOD mutant strains have been constructed to define the role of this molecule in the immune response to M. tuberculosis infection. These studies have suggested that the absence or attenuation of SOD can motivate innate immunity and SOD avoid destruction or growth inhibition of M. tuberculosis. For detailed investigation of how SOD proteins aid M. tuberculosis survival within macrophages, we cloned 2 SOD genes (SODA and SODC) from the M. tuberculosis H37Rv genome, overexpressed, identified, and purified the proteins, and then exposed macrophages to the proteins. Following this, we assessed NO production, the secretion of cytokine interferon-? (IFN-?) and intercellular adhesion molecule-1, the expression of IFN-? receptor and Toll-like receptor 2 on the surface of macrophages, and caspase-3 enzyme activity as well as macrophage apoptosis. Our results showed that both SODA and SODC proteins considerably reduced the production of NO and oxygen radicals and impaired cell immunologic function in early infection.
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[Preparation and evaluation of valerian oil-beta-cyclodextrin inclusion complex].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-09-2013
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The aim of this study was to improve the stability and cover the unpleasant odor of valerian oil by preparation of beta-cyclodextrin inclusion complex. The preparation method was established based on the yield of inclusion complex and entrapment efficiency of valerian volatile oil. After that, the formulation and processing parameters were optimized by uniform design table. The formations of inclusion complex were validated by DSC and X-RD method. The stability of valerian oil beta-cyclodextrin inclusion was studied under stressed conditions. In conclusion, relatively high yield of inclusion complex and entrapment efficiency were obtained by saturated solution-ultrasonication method. Inclusion complex yield and entrapment efficiency of the valerian oil were (84.78 +/- 3.23)% and (86.23 +/- 2.48)%, which were prepared under the optimized conditions, respectively. The results of DSC and X-RD were indicated the formation of inclusion complex. The stability of test showed that the valerian oil-beta-cyclodextrin inclusion complex was improved significantly.
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Depressing Interleukin-1? Contributed to the Synergistic Effects of Tramadol and Minocycline on Spinal Nerve Ligation-Induced Neuropathic Pain.
Neurosignals
PUBLISHED: 10-23-2013
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Our previous study indicated that coadministration of tramadol and minocycline exerted synergistic effects on spinal nerve ligation (SNL)-induced neuropathic mechanical allodynia. However, the underlying mechanisms are still unclear. Recent reports indicated that spinal proinflammatory factor interleukin-1? (IL-1?) contributed to the development of neuropathic pain and the positive feedback communication between neuron and glia. Therefore, the present research is to confirm whether spinal IL-1?-related pathway response contributes to the synergistic effects of tramadol and minocycline on SNL-induced neuropathic pain. Real-time RT-PCR demonstrated IL-1? up-expression in the ipsilateral spinal dorsal horn 3 days after lesion, which could be significantly decreased by tramadol and minocycline coadministration. Immunofluorescence and Western blot indicated that SNL-induced microglial phosphorylated p38 (p-p38) upregulation was also inhibited by tramadol and minocycline coapplication. Meanwhile, intrathecal administration of p38 inhibitor SB203580 markedly alleviated mechanical allodynia whilst reducing IL-1? and Fos expression induced by SNL. Moreover, intrathecal neutralized antibody of IL-1? could depress SNL-induced mechanical allodynia and Fos expression. These results suggest that depressing SNL-induced aberrant activation of the spinal dorsal horn IL-1?-related pathway contributes to the underlying mechanism of the synergistic effects of tramadol and minocycline coadministration on SNL-induced neuropathic mechanical allodynia. © 2013 S. Karger AG, Basel.
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[Nosocomial diarrhea in intensive care unit: other than Clostridium difficile].
Sichuan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 09-25-2013
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To investigate the incidence and clinical features of non-Clostridium difficile (C. difficile) associated nosocomial diarrhea in intensive care unit (ICU) caused by Klebsiella oxytoca and Clostridium perfringens.
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Inhibitory effects of tannic acid on fatty acid synthase and 3T3-L1 preadipocyte.
Biochim. Biophys. Acta
PUBLISHED: 09-19-2013
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Tannic acid is a hydrolyzable tannin that exists in many widespread edible plants with a variety of biological activities. In this study, we found that tannic acid potently inhibited the activity of fatty acid synthase (FAS) in a concentration-dependent manner with a half-inhibitory concentration value (IC50) of 0.14 microM. The inhibition kinetic results showed that the inhibition of FAS by tannic acid was mixed competitive and noncompetitive manner with respect to acetyl-CoA and malonyl-CoA, but uncompetitive to NADPH. Tannic acid prevented the differentiation of 3T3-L1 pre-adipocytes, and thus repressed intracellular lipid accumulation. In the meantime, tannic acid decreased the expression of FAS and down-regulated the mRNA level of FAS and PPARgamma during adipocyte differentiation. Further studies showed that the inhibitory effect of tannic acid did not relate to FAS non-specific sedimentation. Since FAS was believed to be a therapeutic target of obesity, these findings suggested that tannic acid was considered having potential in the prevention of obesity.
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Isolation and Structural Characterization of a Novel Antioxidant Mannoglucan from a Marine Bubble Snail, Bullacta exarata (Philippi).
Mar Drugs
PUBLISHED: 09-11-2013
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Bullacta exarata is one of the most economically important aquatic species in China, noted for not only its delicious taste and nutritional value, but also for its pharmacological activities. In order to explore its potential in medical applications, a mannoglucan designated as BEPS-IB was isolated and purified from the foot muscle of B. exarata after papain digestion. Chemical composition analysis indicated BEPS-IB contained mainly d-glucose and d-mannose in a molar ratio of 1:0.52, with an average molecular weight of about 94 kDa. The linkage information was determined by methylation analysis, and the anomeric configuration and chain linkage were confirmed by IR and 2D NMR. The results indicated BEPS-IB was composed of Glcp6Manp heptasaccharide repeating unit in the backbone, with occasional branch chains of mannose residues (14%) occurring in the backbone mannose. Further antioxidant assay indicated BEPS-IB exhibited positive antioxidant activity in scavenging superoxide radicals and reducing power. This is the first report on the structure and bioactivity of the mannoglucan from the B. exarata.
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Anti-human protein S antibody induces tissue factor expression through a direct interaction with platelet phosphofructokinase.
Thromb. Res.
PUBLISHED: 08-28-2013
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Autoantibodies including anti-human protein S antibody (anti-hPS Ab) and anti-human protein C antibody (anti-hPC Ab) can be detected in patients with autoimmune diseases with hypercoagulability. The objective of the present study was to determine the effects and molecular pathways of these autoantibodies on tissue factor (TF) expression in human coronary artery endothelial cells (HCAECs).
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Simultaneous electrochemical detection of cervical cancer markers using reduced graphene oxide-tetraethylene pentamine as electrode materials and distinguishable redox probes as labels.
Biosens Bioelectron
PUBLISHED: 08-27-2013
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A novel, highly sensitive electrochemical immunoassay was proposed for the simultaneous determination of carcinoembryonic antigen (CEA) and squamous cell carcinoma antigen (SCCA) for the diagnosis of cervical cancer. Using an electrochemical analysis technique, two well-separated peaks were generated by neutral red and thionine, making the simultaneous detection of the two analytes on the electrode possible. Reduced graphene oxide-tetraethylene pentamine (rGO-TEPA), containing more amino groups, was of benefit to immobilize the primary antibody (Ab1) through an amidation reaction. Au@mesoporous carbon CMK-3 was synthesized and incubated with two secondary antibodies (Ab2) and different redox probes (neutral red and thionine) to fabricate the electrochemical immunosensor label intending to improve the analytical performance of the immunosensor. The immunosensor was prepared with a sandwich structure based on the peak current change of neutral red and thionine before and after the antigen-antibody reaction. The results showed that the immunosensor had a wide linear range, low detection limit, good reproducibility and stability. The method has been applied to the analysis of serum samples with satisfactory results.
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Photoacoustic tomography extracted from speckle noise in acoustically inhomogeneous tissue.
Opt Express
PUBLISHED: 08-14-2013
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Photoacoustic tomography is usually limited to acoustically homogeneous tissue. A hybrid scheme is developed to break this limitation by utilizing ultrasound to determine the unknown Greens function of inhomogeneous tissue. The method can effectively decrease the distortion and false contrast in images by extracting information from speckle noise. The method does not depend on the prior knowledge of tissue and the medium complexity. Moreover, the estimation of Greens function and the photoacoustic detection are performed by the same transducer. Therefore, the scheme could be easily integrated into a classical photoacoustic tomography system and extend its application in speckle environment.
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UPLC-PDA determination of paeoniflorin in rat plasma following the oral administration of Radix Paeoniae Alba and its effects on rats with collagen-induced arthritis.
Exp Ther Med
PUBLISHED: 08-05-2013
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Rheumatoid arthritis (RA) is a chronic disabling autoimmune disease with characteristics of chronic, progressive inflammatory joint synovial damage, which mainly encroaches upon the synovium of the joint. The use of traditional medicine to treat RA slows the development of RA to a certain extent; however, it often has numerous side-effects. Therefore, the focus of RA research is the identification of a new, safe and effective medicine. The aim of the present study was to use an ultra performance liquid chromatography and photo diode array (UPLC-PDA) method to detect the paeoniflorin component in a Radix Paeoniae Alba decoction and in rat plasma following the oral administration of Radix Paeoniae Alba decoction. In addition, the effects of paeoniflorin on collagen-induced arthritis (CIA) in rats were investigated. The results indicate that a UPLC-PDA method for determining the presence of paeoniflorin in the Radix Paeoniae Alba decoction was successfully established. The method was fast, simple, sensitive, precise and valid. Paeoniflorin was shown to be a bioactive component of the Radix Paeoniae Alba decoction that was absorbed into rat plasma. Paeoniflorin significantly improved the disease resistant ability of RA rats and reduced the levels of the inflammatory cytokines, IL-1? and TNF-?, thereby inhibiting inflammation and bone erosion in the rats with CIA. The observations are likely to lay the foundation for further study of the mechanism of paeoniflorin in the treatment of RA.
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Heterologous expression and biochemical characterization of glucose isomerase from Thermobifida fusca.
Bioprocess Biosyst Eng
PUBLISHED: 08-01-2013
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Glucose isomerase (GIase) catalyzes the isomerization of D-glucose to D-fructose. The GIase from Thermobifida fusca WSH03-11 was expressed in Escherichia coli BL21(DE3), and the purified enzyme took the form of a tetramer in solution and displayed a pI value of 5.05. The temperature optimum of GIase was 80 °C and its half life was about 2 h at 80 °C or 15 h at 70 °C. The pH optimum of GIase was 10 and the enzyme retained 95 % activity over the pH range of 5-10 after incubating at 4 °C for 24 h. Kinetic studies showed that the K m and K cat values of the enzyme are 197 mM and 1,688 min(-1), respectively. The maximum conversion yield of glucose (45 %, w/v) to fructose of the enzyme was 53 % at pH 7.5 and 70 °C. The present study provides the basis for the industrial application of recombinant T. fusca GIase in the production of high fructose syrup.
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Label-free immunosensor based on Pd nanoplates for amperometric immunoassay of alpha-fetoprotein.
Biosens Bioelectron
PUBLISHED: 07-07-2013
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In this paper, Pd nanoplates were used as a kind of electrode materials for fabrication of an electrochemical immunosensor, which was applied for detection of cancer biomarker alpha-fetoprotein (AFP). Thanks to the unique structure and properties of Pd nanoplates, the antibody of AFP (Ab) was effectively immobilized onto the surface of the Pd nanoplates modified glassy carbon electrode (GCE). Moreover, the good electrochemical properties of Pd nanoplates greatly improved the electronic transmission rate and enhanced the electrochemical signal, which led to an increase of the detection sensitivity. Based on the specific antibody-antigen interaction, a label-free immunosensor based on Pd nanoplates was developed for sensing of AFP. The current method allows us to detect AFP over a wide concentration range from 0.01 to 75.0ng/mL with a detection limit of 4pg/mL. The proposed immunosensor has been used to determine AFP in human serum with satisfactory results.
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Characterization of Sulfolobus solfataricus ?-galactosidase mutant F441Y expressed in Pichia pastoris.
J. Sci. Food Agric.
PUBLISHED: 06-25-2013
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?-galactosidases are usually used to synthesize galactooligosaccharides (GOS). Since thermostable beta-galactosidases have advantages of high optimal temperature, thermostability, as well as the prevention of the bacterial contamination in the production of GOS, they received more attention in research.
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Ultrasensitive electrochemical immunosensors for multiplexed determination using mesoporous platinum nanoparticles as nonenzymatic labels.
Anal. Chim. Acta
PUBLISHED: 06-17-2013
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An ultrasensitive multiplexed immunoassay method was developed at a disposable immunosensor array using mesoporous platinum nanoparticles (M-Pt NPs) as nonenzymatic labels. M-Pt NPs were prepared by ultrasonic method and employed to label the secondary antibody (Ab2) for signal amplification. The immunosensor array was constructed by covalently immobilizing capture antibody (Ab1) on graphene modified screen printed carbon electrodes (SPECs). After the sandwich-type immunoreactions, the M-Pt-Ab2 was bound to immunosensor surface to catalyze the electro-reduction of H2O2 reaction, which produced detectable signals for readout of analytes. Using breast cancer related panel of tumor markers (CA125, CA153 and CEA) as model analytes, this method showed wide linear ranges of over 4 orders of magnitude with the detection limits of 0.002UmL(-1), 0.001UmL(-1) and 7.0pgmL(-1) for CA125, CA153 and CEA, respectively. The disposable immunosensor array possessed excellent clinical value in cancer screening as well as convenient point of care diagnostics.
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The use of tranexamic acid to reduce blood loss and transfusion in major orthopedic surgery: a meta-analysis.
J. Surg. Res.
PUBLISHED: 06-17-2013
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Conflicting reports have been published regarding the effect of tranexamic acid (TXA) on reducing blood loss and transfusion in patients undergoing orthopedic surgery. We performed a meta-analysis to evaluate the effectiveness and safety of TXA treatment in reducing blood loss and transfusion in major orthopedic surgery.
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Copper catalysis for enhancement of cobalt leaching and acid utilization efficiency in microbial fuel cells.
J. Hazard. Mater.
PUBLISHED: 06-09-2013
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Enhancement of both cobalt leaching from LiCoO2 and acid utilization efficiency (AUE) in microbial fuel cells (MFCs) was successfully achieved by the addition of Cu(II). A dosage of 10mg/L Cu(II) improved both cobalt leaching up to 308% and AUE of 171% compared to the controls with no presence of Cu(II). The apparent activation energy of cobalt leaching catalyzed by Cu(II) in MFCs was only 11.8 kJ/mol. These results demonstrate cobalt leaching in MFCs using Cu(II) as a catalyst may be an effective strategy for cobalt recovery and recycle of spent Li-ion batteries, and the evidence of influence factors including solid/liquid ratio, temperature, and pH and solution conductivity can contribute to improving understanding of and optimizing cobalt leaching catalyzed by Cu(II) in MFCs.
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