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Find video protocols related to scientific articles indexed in Pubmed.
Nocturnal bruxism in a patient with behçet disease and posttraumatic stress disorder successfully treated with gabapentin.
Clin Neuropharmacol
PUBLISHED: 11-11-2014
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Bruxism is an involuntary movement, including teeth grinding and clenching, which occur primarily during sleep. Although Behçet disease and posttraumatic stress disorder both have a high prevalence of sleep problems, bruxism is extremely rare in these 2 disorders. Here, we report a rare case of concurrent Behçet disease and posttraumatic stress disorder, which presented with antidepressant-refractory sleep disturbance accompanied by teeth grinding, clenching, and snoring that was successfully treated with gabapentin.
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Crenobacter luteus gen. nov., sp. nov., isolated from a hot spring.
Int. J. Syst. Evol. Microbiol.
PUBLISHED: 10-22-2014
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A slightly thermophilic, Gram-staining negative and strictly aerobic bacteria, designated strain YIM 78141T, was isolated from a sediment sample collected at Hehua hot spring, Tengchong, Yunnan province, south-west China. Cells of the strain were short-rod-shaped and colonies were yellowish and circular. The strain grew at pH 6.0-10.0 (optimum, pH 8.0-9.0) and 10-55 oC (optimum, 40-50 oC). Phylogenetic analyses based on 16S rRNA gene sequence comparison demonstrated that strain YIM 78141T belongs to the family Neisseriaceae, and it also showed low level similarities of 16S rRNA gene sequences (below 93.4%) compared to all other genera in this family. The only quinone was ubiquinone 8 and the genomic DNA G+C content was 67.3 mol%. Major fatty acids (>5 %) were C12:0, C16:0, C18:1 ?7c and summed feature 3. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidyl methylethanolamine, phospholipids of unknown structure containing aminoglycophospholipid and three unidentified polar lipids. On the basis of the morphological, physiological and biochemical characteristics as well as genotypic data, this strain should be classified as a novel genus and species of the family Neisseriaceae, for which the name Crenobacter luteus gen. nov., sp. nov. is proposed. The type strain is YIM 78141T (= BCRC 80650T= KCTC 32558T= DSM 27258T).
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Dual-colored graphene quantum dots-labeled nanoprobes/graphene oxide: functional carbon materials for respective and simultaneous detection of DNA and thrombin.
Nanotechnology
PUBLISHED: 09-24-2014
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Convenient and simultaneous detection of multiple biomarkers such as DNA and proteins with biocompatible materials and good analytical performance still remains a challenge. Herein, we report the respective and simultaneous detection of DNA and bovine ?-thrombin (thrombin) entirely based on biocompatible carbon materials through a specially designed fluorescence on-off-on process. Colorful fluorescence, high emission efficiency, good photostability and excellent compatibility enables graphene quantum dots (GQDs) as the best choice for fluorophores in bioprobes, and thus two-colored GQDs as labeling fluorophores were chemically bonded with specific oligonucleotide sequence and aptamer to prepare two probes targeting the DNA and thrombin, respectively. Each probe can be assembled on the graphene oxide (GO) platform spontaneously by ?-? stacking and electrostatic attraction; as a result, fast electron transfer in the assembly efficiently quenches the fluorescence of probe. The presence of DNA or thrombin can trigger the self-recognition between capturing a nucleotide sequence and its target DNA or between thrombin and its aptamer due to their specific hybridization and duplex DNA structures or the formation of apatamer-substrate complex, which is taken advantage of in order to achieve a separate quantitative analysis of DNA and thrombin. A dual-functional biosensor for simultaneous detection of DNA and thrombin was also constructed by self-assembly of two probes with distinct colors and GO platform, and was further evaluated with the presence of various concentrations of DNA and thrombin. Both biosensors serving as a general detection model for multiple species exhibit outstanding analytical performance, and are expected to be applied in vivo because of the excellent biocompatibility of their used materials.
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[Progress in the studies on neuronal nitric oxide synthase inhibitors].
Yao Xue Xue Bao
PUBLISHED: 09-13-2014
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Nitric oxide (NO), which is involved in the regulation of the cardiovascular system, nervous system, immune system, reproductive system, digestive system and other physiological activities, is an important biological substance with activity. Under normal physiological conditions, neuronal nitric oxide synthase (nNOS) can precisely regulate the nervous system NO production, release, diffusion and inactivation processes. But an excess of NO associates with the development of cerebral ischemia, Alzheimer's and Parkinson's psychosis nervous system diseases, while inhibition of nNOS activity can regulate the content of NO in vivo, and produce a therapeutic effect on some of the nervous system diseases. This review mainly describes the structure and regulation of nNOS and recent developments of small molecule inhibitors of nNOS.
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Genetic analysis and QTL detection for resistance to white tip disease in rice.
PLoS ONE
PUBLISHED: 08-27-2014
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The inheritance of resistance to white tip disease (WTDR) in rice (Oryza sativa L.) was analyzed with an artificial inoculation test in a segregating population derived from the cross between Tetep, a highly resistant variety that was identified in a previous study, and a susceptible cultivar. Three resistance-associated traits, including the number of Aphelenchoides besseyi (A. besseyi) individuals in 100 grains (NA), the loss rate of panicle weight (LRPW) and the loss rate of the total grains per panicle (LRGPP) were analyzed for the detection of the quantitative trait locus (QTL) in the population after construction of a genetic map. Six QTLs distributed on chromosomes 3, 5 and 9 were mapped. qNA3 and qNA9, conferring reproduction number of A. besseyi in the panicle, accounted for 16.91% and 12.54% of the total phenotypic variance, respectively. qDRPW5a and qDRPW5b, associated with yield loss, were located at two adjacent marker intervals on chromosome 5 and explained 14.15% and 14.59% of the total phenotypic variation and possessed LOD values of 3.40 and 3.39, respectively. qDRPW9 was considered as a minor QTL and only explained 1.02% of the phenotypic variation. qLRGPP5 contributed to the loss in the number of grains and explained 10.91% of the phenotypic variation. This study provides useful information for the breeding of resistant cultivars against white tip disease in rice.
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Blockade of mGluR5 in the nucleus accumbens shell but not core attenuates heroin seeking behavior in rats.
Acta Pharmacol. Sin.
PUBLISHED: 08-20-2014
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Aim:Glutamatergic neurotransmission in the nucleus accumbens (NAc) is crucial for the relapse to heroin seeking. The aim of this study was to determine whether mGluR5 in the NAc core or shell involved in heroin seeking behavior in rats.Methods:Male SD rats were self-administered heroin under a fixed-ratio 1 (FR1) reinforcement schedule for 14 d, and subsequently withdrawn for 2 weeks. The selective mGluR5 antagonist 2-methyl-6-phenylethynyl-pyridine (MPEP, 5, 15 and 50 nmol per side) was then microinjected into the NAc core or shell 10 min before a heroin-seeking test induced by context, cues or heroin priming.Results:Microinjection of MPEP into the NAc shell dose-dependently decreased the heroin seeking induced by context, cues or heroin priming. In contrast, microinjection of MPEP into the NAc core did not alter the heroin seeking induced by cues or heroin priming. In addition, microinjection with MPEP (15 nmol per side) in the NAc shell reversed both the percentage of open arms entries (OE%) and the percentage of time spent in open arms (OT%) after heroin withdrawal. Microinjection of MPEP (50 nmol per side) in the striatum as a control location did not affect the heroin seeking behavior. Microinjection of MPEP in the 3 locations did not change the locomotion activities.Conclusion:Blockade of mGluR5 in NAc shell in rats specifically suppresses the relapse to heroin-seeking and anxiety-like behavior, suggesting that mGluR5 antagonists may be a potential candidate for the therapy of heroin addiction.
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Hemoglobin A1c risk score for the prediction of coronary artery disease in subjects with angiographically diagnosed coronary atherosclerosis.
Cell. Physiol. Biochem.
PUBLISHED: 08-18-2014
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To develop a risk score by incorporating Hemoglobin A1c(HbA1c) with traditional risk factors for the prediction of coronary artery disease (CAD) in Chinese subjects.
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Simultaneous Detection of Multiple DNA Targets by Integrating Dual-Color Graphene Quantum Dot Nanoprobes and Carbon Nanotubes.
Chemistry
PUBLISHED: 08-04-2014
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Simultaneous detection of multiple DNA targets was achieved based on a biocompatible graphene quantum dots (GQDs) and carbon nanotubes (CNTs) platform through spontaneous assembly between dual-color GQD-based probes and CNTs and subsequently self-recognition between DNA probes and targets.
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[Topological models of retention index of thin-layer chromatogram for chiral organic acids].
Se Pu
PUBLISHED: 07-03-2014
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On the basis of Kier's molecular connectivity indices and conjugated matrix, novel molecular connectivity indices ((m) G(t)(v)) were defined and calculated for 18 chiral hydroxyl acids and amino acids. The chiral connectivity indices ((m)C(t)(v)) were introduced by extending (m)G(t)(v): (m)C(t)(v) = (m)G(t)(v) x w(j), where w(j) is the chiral index. The quantitative structure-retention index relationship (QSRR) between the retention index (R(M)) of thin-layer chromatogram for the chiral organic acids and (m)C(t)(v) was studied by multivariate statistical regression. By leaps-and-bounds regression analysis, the best four-parameter QSRR model was set up, and the traditional correlation coefficient (R2) and the cross-validation correlation coefficient (Q2) of leave-one-out (LOO) were 0.973 and 0.950, respectively. The results demonstrated that the model was highly reliable and had good predictive ability from the point of view of statistics. From the four parameters (0C(p)(v), 2C(p)(v), C(ch),(v), 5C(p)(v)) of the model, it is known that the dominant influence factors of the retention index were the molecular structure characteristics of two-dimensional and the space factors: the chiral characteristics, the flexibility and the puckered degree of molecules for the chiral organic acids. The results showed that the new parameter mC(t)(v) had good rationality and efficiency for the retention indices of the chiral organic acids. Therefore, an effective method was provided to predict the retention indices of the chiral organic acids.
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Cucurbitacin-E inhibits multiple cancer cells proliferation through attenuation of Wnt/?-catenin signaling.
Cancer Biother. Radiopharm.
PUBLISHED: 06-02-2014
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Recent studies suggest that the use of cucurbitacins could inhibit cancer cell progression. In the current study, the authors analyzed the effect of cucurbitacin-E (CuE) in cancer cells using A549, Hep3B, and SW480 cells. The authors found that CuE inhibited cell proliferation and modulated the expression of cell cycle regulators in these cells. Moreover, the authors found that CuE inhibited Wnt/?-catenin signaling activation through upregulation of tumor suppressor Menin. Indeed, ablation of Menin using small interfering RNA (siRNA) oligos attenuated the antiproliferative roles of CuE. Taken together, the results of this study provide a novel mechanism that may contribute to the antineoplastic effects of CuE in cancer cells.
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Independent control of differently-polarized waves using anisotropic gradient-index metamaterials.
Sci Rep
PUBLISHED: 05-16-2014
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We propose a kind of anisotropic gradient-index (GRIN) metamaterials, which can be used to control differently-polarized waves independently. We show that two three- dimensional (3D) planar lenses made of such anisotropic GRIN metamaterials are able to make arbitrary beam deflections for the vertical (or horizontal) polarization but have no response to the horizontal (or vertical) polarization. Then the vertically- and horizontally-polarized waves are separated and controlled independently to deflect to arbitrarily different directions by designing the anisotropic GRIN planar lenses. We make experimental verifications of the lenses using such a special metamaterial, which has both electric and magnetic responses simultaneously to reach approximately equal permittivity and permeability. Hence excellent impedance matching is obtained between the GRIN planar lenses and the air. The measurement results demonstrate good performance on the independent controls of differently-polarized waves, as observed in the numerical simulations.
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[Diurnal and seasonal variations of energy balance over Horqin meadow].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 04-29-2014
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Based on the measurements of eddy flux and micrometeorological factors, this paper analyzed the diurnal and seasonal variations of energy balance over Horqin meadow. The results showed that annual energy balance ratio (EBR) of the eddy covariance system was 0.77, and EBR was biggest in growing season, middle in bare soil period and smallest in snow-covered period. Diurnal variations of energy components all presented bell-shaped curves. The peak of net radiation appeared around 12:00 and peaks of other components slightly lagged. Seasonal variation of net radiation presented a single-peak curve, and the annual average was 5.71 MJ x m(-2) x d(-1). Seasonal variation of latent heat flux was similar to that of net radiation, and the annual average was 2.84 MJ x m(-2) x d(-1). Seasonal variation of sensible heat flux presented a double-peak curve, and the peaks appeared in April and September, respectively. Annual averaged sensible heat flux was 1.87 MJ x m(-2) x d(-1). Maximum soil heat flux (3.47 MJ x m(-2) x d(-1)) appeared in April, and the soil heat flux became negative after September. Annual budget ratios of energy components presented a decreasing order of latent heat flux, sensible heat flux and soil heat flux, which accounted for 49.8%, 35.8% and 3.1% of net radiation, respectively. Seasonal variation of Bowen ratio (beta) presented a 'U' shape, and the annual average was 1.61. beta was small (0.18) and relatively stable in growing season, while it was large (2.39) and fluctuated severely in non-growing season.
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Atypical antipsychotic drug treatment for 6 months restores N-acetylaspartate in left prefrontal cortex and left thalamus of first-episode patients with early onset schizophrenia: A magnetic resonance spectroscopy study.
Psychiatry Res
PUBLISHED: 04-18-2014
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Early onset schizophrenia (EOS) is often associated with poorer outcomes, including lack of school education, higher risk of mental disability and resistance to treatment. But the knowledge of the neurobiological mechanism of EOS is limited. Here, using proton magnetic resonance spectroscopy, we investigated the possible neurochemical abnormalities in prefrontal cortex (PFC) and thalamus of first-episode drug-naïve patients with EOS, and followed up the effects of atypical antipsychotic treatment for 6 months on neurochemical metabolites and clinical symptoms. We measured the ratios of N-acetylaspartate (NAA), choline (Cho) to creatine (Cr) in 41 adolescents with first episode of EOS and in 28 healthy controls matched for age, gender, and years of education. The EOS patients presented with abnormally low NAA/Cr values in the left PFC and left thalamus with a reduced tendency in the right PFC compared with healthy controls. No significant differences were detected between groups for Cho/Cr in PFC and thalamus in any hemisphere. After atypical antipsychotic treatment for 6 months, the reduced NAA/Cr in the left PFC and left thalamus in EOS patients was elevated to the normal level in healthy controls, without any alteration in Cho/Cr. We also found that there was no significant correlation between the neurochemical metabolite ratios in the PFC and thalamus in patients with EOS, and clinical characteristics. Our results suggest that there was neurochemical metabolite abnormalities in PFC and thalamus in EOS patients, atypical antipsychotic treatment can effectively relieve the symptoms and restore the reduced NAA in PFC and thalamus.
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Si-doped carbon quantum dots: a facile and general preparation strategy, bioimaging application, and multifunctional sensor.
ACS Appl Mater Interfaces
PUBLISHED: 04-18-2014
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Heteroatom doping of carbon quantum dots not only enables great improvement of fluorescence efficiency and tunability of fluorescence emission, but also provides active sites in carbon dots to broaden their application in sensor. Silicon as a biocompatible element offers a promising direction for doping of carbon quantum dots. Si-doped carbon quantum dots (SiCQDs) were synthesized through a facile and effective approach. The as-prepared Si-doped carbon quantum dots possess visible fluorescence with high quantum yield up to 19.2%, owing to fluorescence enhancement effect of introduced silicon atoms into carbon dots. The toxicity test on human Hela cells showed that SiCQDs have lower cellular toxicity than common CQDs, and bioimaging experiments clearly demonstrated their excellent biolabelling ability and outstanding performance in resistance to photobleaching. Strong fluorescence quenching effect of Fe(III) on SiCQDs can be used for its selective detection among general metal ions. Specific electron transfer between SiCQDs and hydrogen peroxide enables SiCQDs as a sensitive fluorescence sensing platform for hydrogen peroxide. The subsequent fluorescence recovery induced by removal of hydrogen peroxide from SiCQDs due to formation of the stable adducts between hydrogen peroxide and melamine was taken advantage of to construct effective sensor for melamine.
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B-doped carbon quantum dots as a sensitive fluorescence probe for hydrogen peroxide and glucose detection.
Analyst
PUBLISHED: 04-04-2014
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Fluorescent B-doped carbon quantum dots (BCQDs) were prepared by a facile one-pot solvothermal route. The BCQDs can be used as a novel fluorescence sensing system for hydrogen peroxide and glucose detection.
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Combining high-throughput phenotyping and genome-wide association studies to reveal natural genetic variation in rice.
Nat Commun
PUBLISHED: 04-03-2014
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Even as the study of plant genomics rapidly develops through the use of high-throughput sequencing techniques, traditional plant phenotyping lags far behind. Here we develop a high-throughput rice phenotyping facility (HRPF) to monitor 13 traditional agronomic traits and 2 newly defined traits during the rice growth period. Using genome-wide association studies (GWAS) of the 15 traits, we identify 141 associated loci, 25 of which contain known genes such as the Green Revolution semi-dwarf gene, SD1. Based on a performance evaluation of the HRPF and GWAS results, we demonstrate that high-throughput phenotyping has the potential to replace traditional phenotyping techniques and can provide valuable gene identification information. The combination of the multifunctional phenotyping tools HRPF and GWAS provides deep insights into the genetic architecture of important traits.
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Understanding the polypharmacological anticancer effects of Xiao Chai Hu Tang via a computational pharmacological model.
Exp Ther Med
PUBLISHED: 03-25-2014
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Xiao Chai Hu Tang (XCHT), a traditional herbal formula, is widely administered as a cancer treatment. However, the underlying molecular mechanisms of its anticancer effects are not fully understood. In the present study, a computational pharmacological model that combined chemical space mapping, molecular docking and network analysis was employed to predict which chemical compounds in XCHT are potential inhibitors of cancer-associated targets, and to establish a compound-target (C-T) network and compound-compound (C-C) association network. The identified compounds from XCHT demonstrated diversity in chemical space. Furthermore, they occupied regions of chemical space that were the same, or close to, those occupied by drug or drug-like compounds that are associated with cancer, according to the Therapeutic Targets Database. The analysis of the molecular docking and the C-T network demonstrated that the potential inhibitors possessed the properties of promiscuous drugs and combination therapies. The C-C network was classified into four clusters and the different clusters contained various multi-compound combinations that acted on different targets. The study indicated that XCHT has a polypharmacological role in treating cancer and the potential inhibitory components of XCHT require further investigation as potential therapeutic strategies for cancer patients.
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Relationship of renin-angiotensin-aldosterone system polymorphisms and phenotypes to mortality in Chinese coronary atherosclerosis patients.
Sci Rep
PUBLISHED: 03-12-2014
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We performed a large, long-term cohort study to evaluate the association of renin-angiotensin-aldosterone system gene polymorphisms and baseline phenotypes to all-cause mortality among patients with angiographically confirmed coronary atherosclerosis. The study included 1075 subjects who underwent coronary angiography. Patients were genotyped for eight polymorphisms (rs4343, rs5186, rs5182, rs5049, rs5051, rs699, rs4762, and rs1799998), and their baseline plasma angiotensin II and aldosterone levels were measured. The interval between baseline and follow-up time-points ranged from 6.39 to 9.59 years. The results of multivariate regression analysis further indicated that high baseline angiotensin II levels (1.226 (1.024-1.468), p = 0.027) were independently associated with all-cause death. Therefore, we found that an increased baseline plasma angiotensin II level was associated with higher long-term all-cause mortality, even after correcting for established cardiovascular risk factors.
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Directional transfer of a multiple-allele male sterile line in Brassica campestris L. ssp. chinensis (L.) Makino var. rosularis Tsen et Lee.
Breed. Sci.
PUBLISHED: 03-02-2014
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To produce hybrid seeds of Wutacai (Brassica campestris L. ssp. chinensis (L.) Makino var. rosularis Tsen et Lee), a "directional transfer program" was designed to breed the multiple-allele male sterile line of Wutacai. A multiple-allele male sterile line of Naibaicai (Brassica campestris L. ssp. chinensis L., S01) was used as the male sterile resource, and an inbred line of Wutacai (WT01) was used as the target line. Recurrent backcrossing was employed to transfer the male sterility and other botanical traits simultaneously, while the genotype was identifiedthrough test crossing. The male sterility was successfully transferred from S01 to WT01. A new male sterile line, GMS-3, with similar botanical traits to WT01, was bred. Four hybrid combinations were generated with GMS-3 as the female parent. One hybrid (C1) that contained the most desirable traits was developed from the new male sterile line.
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Selective beta-1 blockers deteriorate glucose metabolism. A meta-analysis.
Saudi Med J
PUBLISHED: 02-25-2014
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To provide an up-to-date synthesis of available data, and to quantify the effect of highly selective beta-1 blockers on glucose metabolism in patients with essential hypertension and type diabetes mellitus (T2DM) by using pooled analysis techniques.
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DNA nanosensor based on biocompatible graphene quantum dots and carbon nanotubes.
Biosens Bioelectron
PUBLISHED: 02-23-2014
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An ultrasensitive nanosensor based on fluorescence resonance energy transfer (FRET) between biocompatible graphene quantum dots and carbon nanotubes for DNA detection was reported. We take advantage of good biocompatibility and strong fluorescence of graphene quantum dots, base pairing specificity of DNA and unique fluorescence resonance energy transfer between graphene quantum dots and carbon nanotubes to achieve the analysis of low concentrations of DNA. Graphene quantum dots with high quantum yield up to 0.20 were prepared and served as the fluorophore of DNA probe. FRET process between graphene quantum dots-labeled probe and oxidized carbon nanotubes is easily achieved due to their efficient self-assembly through specific ?-? interaction. This nanosensor can distinguish complementary and mismatched nucleic acid sequences with high sensitivity and good reproducibility. The detection method based on this nanosensor possesses a broad linear span of up to 133.0 nM and ultralow detection limit of 0.4 nM. The constructed nanosensor is expected to be highly biocompatible because of all its components with excellent biocompatibility.
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Roseomonas alkaliterrae sp. nov., isolated from an alkali geothermal soil sample in Tengchong, Yunnan, South-West China.
Antonie Van Leeuwenhoek
PUBLISHED: 02-21-2014
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An alkalitolerant, thermotolerant and Gram-stain negative bacterium, designated strain YIM 78007(T), was isolated from an alkaline geothermal soil sample from Hehua hot spring, Tengchong, Yunnan province, south-west China. Cells of strain YIM 78007(T) were observed to be aerobic and short rod-shaped. The colonies were observed to be orange-red, convex and circular. 16S rRNA gene sequence-based phylogenetic analysis showed that strain YIM 78007(T) clustered with members of the genus Roseomonas (with similarities from 97.2 to 92.2 %). Optimal growth of strain YIM 78007 occurs at 40-50 °C and pH 8.0-10.0. The predominant ubiquinone was identified as Q-10 and the major fatty acids were identified as C18:1 ?7c and C16:0. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, two unidentified aminolipids and one unknown phospholipid. The G + C content of the genomic DNA was determined to be 63 mol %. The levels of DNA-DNA hybridization relatedness between strain YIM 78007(T) and its closet neighbours (Roseomonas lacus JCM 13283(T) and Roseomonas terrae JCM 14592(T)) were well below the threshold required for the proposal of a novel species. The results of physiological and biochemical characteristics, the phylogenetic analysis, as well as low DNA-DNA hybridization values, allowed the phenotypic and genotypic differentiation of strain YIM 78007(T) from its closest phylogenetic neighbours. Therefore, strain YIM 78007(T) is considered to represent a novel species of the genus Roseomonas, for which the name Roseomonas alkaliterrae sp. nov. is proposed. The type strain is YIM 78007(T) (=BCRC 80644(T) = JCM 19656(T)).
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Images in clinical medicine: An unusual auricular foreign body.
N. Engl. J. Med.
PUBLISHED: 02-14-2014
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A 48-year-old woman presented to the emergency department with severe otalgia of 1 day's duration. Bloody otorrhea in the left ear was noted after her hearing aid was removed. A video shows findings in the auditory canal.
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Randomized controlled trial: moxibustion and acupuncture for the treatment of Crohn's disease.
World J. Gastroenterol.
PUBLISHED: 02-10-2014
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To evaluate the clinical efficacy and safety of acupuncture and moxibustion for the treatment of active Crohn's disease (CD).
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Synthesis of (Z)-1-thio- and (Z)-2-thio-1-alkenyl boronates via copper-catalyzed regiodivergent hydroboration of thioacetylenes: an experimental and theoretical study.
J. Org. Chem.
PUBLISHED: 02-10-2014
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A Cu-catalyzed divergent hydroboration of thioacetylenes has been achieved, providing (Z)-1-thio- or (Z)-2-thio-1-alkenyl boronates in moderate to high yields with excellent regio- and stereoselectivity, by using pinacolborane or bis(pinacolato)diboron as the hydroborating reagents, respectively. DFT calculations indicate that the sulfur atom plays a key role in determining the regioselectivity through polarizing the C-C triple bonds and participating in the HOMO orbitals. Moreover, the SR group can serve as a good leaving group, resulting in the concise synthesis of six regio- and stereoisomers of trisubstituted alkenes 5 via the iterative cross-coupling of C-B and C-S bonds. Clearly, it will be valuable for assembling stereochemically diverse trisubstituted olefins in organic synthesis.
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c-Jun N-terminal kinase - c-Jun pathway transactivates Bim to promote osteoarthritis.
Can. J. Physiol. Pharmacol.
PUBLISHED: 02-08-2014
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Osteoarthritis (OA) is a chronic degenerative joint disorder. Previous studies have shown abnormally increased apoptosis of chondrocytes in patients and animal models of OA. TNF-? and nitric oxide have been reported to induce chondrocyte ageing; however, the mechanism of chondrocyte apoptosis induced by IL-1? has remained unclear. The aim of this study is to identify the role of the c-Jun N-terminal kinase (JNK) - c-Jun pathway in regulating induction of Bim, and its implication in chondrocyte apoptosis. This study showed that Bim is upregulated in chondrocytes obtained from the articular cartilage of OA patients and in cultured mouse chondrocytes treated with IL-1?. Upregulation of Bim was found to be critical for chondrocyte apoptosis induced by IL-1?, as revealed by the genetic knockdown of Bim, wherein apoptosis was greatly reduced in the chondrocytes. Moreover, activation of the JNK-c-Jun pathway was observed under IL-1? treatment, as indicated by the increased expression levels of c-Jun protein. Suppression of the JNK-c-Jun pathway, using chemical inhibitors and RNA interference, inhibited the Bim upregulation induced by IL-1?. These findings suggest that the JNK-c-Jun pathway is involved in the upregulation of Bim during OA and that the JNK-c-Jun-Bim pathway is vital for chondrocyte apoptosis.
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Loss of function tp53 mutations do not accelerate the onset of myc-induced T-cell acute lymphoblastic leukaemia in the zebrafish.
Br. J. Haematol.
PUBLISHED: 02-05-2014
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The TP53 tumour suppressor is activated in response to distinct stimuli, including an ARF-dependent response to oncogene stress and an ATM/ATR-dependent response to DNA damage. In human T-cell acute lymphoblastic leukaemia (T-ALL), TP53-dependent tumour suppression is typically disabled via biallelic ARF deletions. In murine models, loss of Arf (Cdkn2a) or Tp53 markedly accelerates the onset of Myc-induced lymphoblastic malignancies. In zebrafish, no ARF ortholog has been identified, but the sequence of ARF is very poorly conserved evolutionarily, making it difficult to exclude the presence of a zebrafish ARF ortholog without functional studies. Here we show that tp53 mutations have no significant influence on the onset of myc-induced T-ALL in zebrafish, consistent with the lack of additional effects of Tp53 loss on lymphomagenesis in Arf-deficient mice. By contrast, irradiation leads to complete T-ALL regression in tp53 wild-type but not homozygous mutant zebrafish, indicating that the tp53-dependent DNA damage response is intact. We conclude that tp53 inactivation has no impact on the onset of myc-induced T-ALL in the zebrafish, consistent with the lack of a functional ARF ortholog linking myc-induced oncogene stress to tp53-dependent tumour suppression. Thus, the zebrafish model is well suited to the study of ARF-independent pathways in T-ALL pathobiology.
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Zhizhongheella caldifontis gen. nov., sp. nov., a novel member of the family Comamonadaceae.
Antonie Van Leeuwenhoek
PUBLISHED: 01-29-2014
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An alkalitolerant, thermotolerant, strictly aerobic and Gram-staining negative bacterial strain, designated YIM 78140(T), was isolated from a water sample in Hehua hot spring, Tengchong, Yunnan province, south-west China. The colonies were light brown, convex and circular. Phylogenetic analysis of the 16S rRNA gene sequence of strain YIM 78140(T) indicated that it was clustered with members of ?-Proteobacteria (with the similarity from 96.9 to 93.6 %). Good growth occurred at 40-50 °C, pH 8.0-9.0 and in the presence of 0-3 % (w/v) NaCl. The predominant ubiquinones were Q-8 and Q-9. The major fatty acids were C16:0, C17:0 cyclo, C18:1 ?7c and summed feature 3. The G+C content of genomic DNA was 70.8 mol%. The results of physiological and biochemical characteristics, phylogenetic analysis allowed the phenotypic and genotypic differentiation of strain YIM 78140(T) from its closest phylogenetic neighbours. Therefore, the strain YIM 78140(T) represents a novel genus of the family Comamonadaceae, for which the name Zhizhongheella caldifontis gen. nov., sp. nov. is proposed. The type strain is YIM 78140(T) (= BCRC 80649(T) = KCTC 32557(T)).
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Reversible immortalization of human hepatocytes mediated by retroviral transfer and site-specific recombination.
World J. Gastroenterol.
PUBLISHED: 01-26-2014
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To establish a method for the reversible immortalization of human hepatocytes, which may offer a good and safe source of hepatocytes for practical applications.
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Solution-phase catalytic synthesis, characterization and growth kinetics of Ag2S-CdS matchstick-like heteronanostructures.
Dalton Trans
PUBLISHED: 01-24-2014
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A facile catalytic growth route was developed for the low-temperature solution synthesis of Ag2S-CdS matchstick-like heteronanostructures in oleylamine, which are composed of a Ag2S spherical head and a CdS rod-like stem. Ag2S nanoseeds acted as an effective catalyst for the growth of CdS nanorods and remained at the tip of the resultant nanorods, leading to the formation of Ag2S-CdS heterostructures with a matchstick shape. The diameter of the Ag2S heads and the length of the CdS stems could be easily controlled by varying the molar ratios of the Ag/Cd precursors. The differential scanning calorimetry (DSC) and variable-temperature X-ray diffraction (XRD) studies confirmed that Ag2S catalytic seeds underwent a phase change, that is, they were in a high-temperature superionic conducting cubic structure during the CdS nanorod growth and then converted to a low-temperature monoclinic crystal structure as the reaction was cooled to room temperature. The influence of synthetic temperature on the product morphology was investigated and the morphological evolution at different growth stages was monitored using transmission electron microscopy (TEM). Furthermore, the growth kinetics of the Ag2S-CdS matchstick-like heteronanostructures, including the dissolution, nucleation and growth of CdS within the Ag2S catalyst, was reasonably discussed on the basis of the structural characteristics of the superionic cubic Ag2S catalyst and the low solubility of CdS in Ag2S derived from the Ag2S-CdS binary phase diagram.
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Highly luminescent N-doped carbon quantum dots as an effective multifunctional fluorescence sensing platform.
Chemistry
PUBLISHED: 01-21-2014
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The doping of carbon quantum dots with nitrogen provides a promising direction to improve fluorescence performance and broaden their applications in sensing systems. Herein we report a one-pot solvothermal synthesis of N-doped carbon quantum dots (NCQDs) and the synthesis of a series of NCQDs with different nitrogen contents. The as-prepared NCQDs were compared with carbon quantum dots (CQDs); the introduction of nitrogen atoms largely increased the quantum yield of NCQDs and highest emission efficiency is up to 36.3?%. The fluorescence enhancement may originate from more polyaromatic structures induced by incorporated nitrogen atoms and protonation of nitrogen atoms on dots. It was found that NCQDs can act as a multifunctional fluorescence sensing platform because they can be used to detect pH values, Ag(I), and Fe(III) in aqueous solution. The fluorescence intensity of NCQDs is inversely proportional to pH values across a broad range from 5.0 to 13.5, which indicates that NCQDs can be devised as an effective pH indicator. Selective detection of Ag(I) and Fe(III) was achieved based on their distinctive fluorescence influence because Ag(I) can significantly enhance the fluorescence whereas Fe(III) can greatly quench the fluorescence. The quantitative determination of Ag(I) can be accomplished with NCQDs by using the linear relationship between fluorescence intensity of NCQDs and concentration of Ag(I). The sensitive detection of H2O2 was developed by taking advantage of the distinct quenching ability of Fe(III) and Fe(II) toward the fluorescence of NCQDs. Cellular toxicity test showed NCQDs still retain low toxicity to cells despite the introduction of a great deal of nitrogen atoms. Moreover, bioimaging experiments demonstrated that NCQDs have stronger resistance to photobleaching than CQDs and more excellent fluorescence labeling performance.
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Experimental imaging properties of immersion microscale spherical lenses.
Sci Rep
PUBLISHED: 01-21-2014
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Using the immersion lensing technique, the resolution of a conventional spherical lens can be improved by a factor of 1/n over its value in air (n, the refractive index of the immersion medium). Depending on the relative position between an object and a lens, either a real or a virtual image is formed. Here we report a new physical phenomenon experimentally observed in the microscale lens imaging. We find that when a microscale spherical lens is semi-immersed in a medium, the resolution of the lens is improved as it can intercept more fine details of the object. However, the microscale lens has two image channels for the fine and coarse details and two images corresponding to the two components can be formed simultaneously. Our findings will advance the understanding of the super-resolution imaging mechanisms in microscale lenses.
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In silico search for multi-target therapies for osteoarthritis based on 10 common Huoxue Huayu herbs and potential applications to other diseases.
Mol Med Rep
PUBLISHED: 01-16-2014
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Huoxue Huayu (HXHY) has been widely used in traditional Chinese medicine (TCM) as a key therapeutic principle for osteoarthritis (OA), and related herbs have been widely prescribed to treat OA in the clinic. The aims of the present study were to explore a multi-target therapy for OA using 10 common HXHY herbs and to investigate their potential applications for treatment of other diseases. A novel computational simulation approach that integrates chemical structure, ligand clusters, chemical space and drug?likeness evaluations, as well as docking and network analysis, was used to investigate the properties and effects of the herbs. The compounds contained in the studied HXHY herbs were divided into 10 clusters. Comparison of the chemical properties of these compounds to those of other compounds described in the DrugBank database indicated that the properties of the former are more diverse than those of the latter and that most of the HXHY-derived compounds do not violate the 'Lipinski's rule of five'. Docking analysis allowed for the identification of 39 potential bioactive compounds from HXHY herbs and 11 potential targets for these compounds. The identified targets were closely associated with 49 diseases, including neoplasms, musculoskeletal, nervous system and cardiovascular diseases. Ligand?target (L?T) and ligand?target?disease (L?T?D) networks were constructed in order to further elucidate the pharmacological effects of the herbs. Our findings suggest that a number of compounds from HXHY herbs are promising candidates for mult?target therapeutic application in OA and may exert diverse pharmacological effects, affecting additional diseases besides OA.
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Contrasting regeneration strategies in climax and long-lived pioneer tree species in a subtropical forest.
PLoS ONE
PUBLISHED: 01-01-2014
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1: This study investigated 15 coexisting dominant species in a humid subtropical evergreen broad-leaved forest in southwest China, consisting of long-lived pioneers and climax species occurring in natural and disturbed regimes. The authors hypothesized that there would be non-tradeoff scaling relationships between sprouting and seed size among species, with the aim of uncovering the ecological relationship between plant sprouting and seed characteristics in the two functional groups. 2: The sprouting variations of the species were initially examined using pairwise comparisons between natural and disturbed habitats within and across species and were noted to show a continuum in persistence niches across the forest dominants, which may underlie the maintenance of plant diversity. Second, a significantly positive, rather than tradeoff, relationship between sprout number and seed size across species within each of the two functional groups was observed, and an obvious elevational shift with a common slope among the two groups in their natural habitat was examined. The results indicate the following: 1) the relationship of seed size vs. sprouts in the natural habitat is more likely to be bet-hedging among species within a guild in a forest; 2) climax species tend to choose seeding rather than sprouting regeneration, and vice versa for the long-lived pioneers; and 3) the negative correlation between sprouting and seed dispersal under disturbed conditions may imply a tradeoff between dispersal and persistence in situ during the process of plant regeneration. 3: These findings may be of potential significance for urban greening using native species.
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Combined Effects of Admission Serum Creatinine Concentration with Age and Gender on the Prognostic Significance of Subjects with Acute ST-Elevation Myocardial Infarction in China.
PLoS ONE
PUBLISHED: 01-01-2014
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to explore the impact of admission serum creatinine concentration on the in-hospital mortality and its interaction with age and gender in patients with acute ST-segment elevation myocardial infarction (STEMI) in China.
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Prospective screening of family members with moyamoya disease patients.
PLoS ONE
PUBLISHED: 01-01-2014
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Genetic factors play an important role in the pathogenesis of moyamoya disease (MMD). Previous studies concentrated on familial MMD patients. In this study, we focused on family members of sporadic MMD patients, and aimed to gain a clearer understanding of the role that genetic factors play in MMD.
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Isolation and characterization of a rhizobacterial antagonist of root-knot nematodes.
PLoS ONE
PUBLISHED: 01-01-2014
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The rhizobacterial strain Jdm2 was isolated from the rhizosphere of the traditional Chinese medicinal herb Trichosanthes kirilowii in Jiangsu province, China, and was identified as Bacillus subtilis. Exposure of cell-free filtrate of the strain to the root-knot nematode Meloidogyne incognita under in vitro conditions caused substantial mortality of the second stage juvenile (J2) and significantly reduced egg hatchability. A greenhouse trial demonstrated that 56 days after treatment with Jdm2, the number of galls associated with M. incognita infection in the tomato (Solanum lycopersicum) roots was significantly reduced compared to controls, and the disease severity of infected plants was lower in treated plants (36%) compared to water control (75%). Consistently, in the field trial, the biocontrol efficacy of Jdm2 reached 69%, 51% and 48% after 30, 60 and 90 days post-transplantation, respectively. As indicated by PCR-DGGE analysis, inoculation with Jdm2 strain had an effect on the bacterial community of the tomato rhizosphere at the first stage, but was not able to imperil the bacterial community stability for long time. The novel bacterial strain Jdm2 enhances plant growth and inhibits nematode activity, and has the potential to be a safe and effective microbial pesticide.
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[The accuracy of probing depth measurements of undergraduate students and associated factors analysis].
Zhonghua Kou Qiang Yi Xue Za Zhi
PUBLISHED: 11-23-2013
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To investigate the accuracy of probing depth measurements of undergraduate students in department of periodontology and analyze the cause of measurement errors.
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Combating infectious diseases of poverty: a year on.
Infect Dis Poverty
PUBLISHED: 10-25-2013
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The Infectious Diseases of Poverty journal, launched a year ago, is a platform to engage outside the traditional disciplinary boundaries, and disseminate high quality science towards the improvement of health. This paper reviews the milestone achievements during its first year of operation. The journal has filled an important niche, addressing some of the main priorities in the Global Report for Research on Infectious Diseases of Poverty. Highlights include the publication of three thematic issues on health systems, surveillance and response systems, as well as co-infection and syndemics. The thematic issues have foregrounded the importance and innovation that can be achieved through transdisciplinary research. The journal has been indexed by PubMed since April 2013, with the publication of a total of 38 articles. Finally, the journal is delivering to wider range readers both in developing and developed countries with sustained efforts with a focus on relevant and strategic information towards elimination of infectious diseases of poverty.
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A hyperspectral imaging system for an accurate prediction of the above-ground biomass of individual rice plants.
Rev Sci Instrum
PUBLISHED: 10-05-2013
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Biomass is an important component of the plant phenomics, and the existing methods for biomass estimation for individual plants are either destructive or lack accuracy. In this study, a hyperspectral imaging system was developed for the accurate prediction of the above-ground biomass of individual rice plants in the visible and near-infrared spectral region. First, the structure of the system and the influence of various parameters on the camera acquisition speed were established. Then the system was used to image 152 rice plants, which selected from the rice mini-core collection, in two stages, the tillering to elongation (T-E) stage and the booting to heading (B-H) stage. Several variables were extracted from the images. Following, linear stepwise regression analysis and 5-fold cross-validation were used to select effective variables for model construction and test the stability of the model, respectively. For the T-E stage, the R(2) value was 0.940 for the fresh weight (FW) and 0.935 for the dry weight (DW). For the B-H stage, the R(2) value was 0.891 for the FW and 0.783 for the DW. Moreover, estimations of the biomass using visible light images were also calculated. These comparisons showed that hyperspectral imaging performed better than the visible light imaging. Therefore, this study provides not only a stable hyperspectral imaging platform but also an accurate and nondestructive method for the prediction of biomass for individual rice plants.
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[Dark respiration of terrestrial vegetations: a review].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 09-27-2013
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The source and sink effect of terrestrial plants is one of the hotspots in terrestrial ecosystem research under the background of global change. Dark respiration of terrestrial plants accounts for a large fraction of total net carbon balance, playing an important role in the research of carbon cycle under global climate change. However, there is little study on plant dark respiration. This paper summarized the physiological processes of plant dark respiration, measurement methods of the dark respiration, and the effects of plant biology and environmental factors on the dark respiration. The uncertainty of the dark respiration estimation was analyzed, and the future hotspots of related researches were pointed out.
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Vaccination with plasmid DNA encoding a mutant toxic shock syndrome toxin-1 ameliorates toxin-induced lethal shock in mice.
Tohoku J. Exp. Med.
PUBLISHED: 08-30-2013
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Staphylococcal toxic shock syndrome toxin-1 (TSST-1), a superantigenic toxin produced by Staphylococcus (S.) aureus, is a major cause of septic shock and toxic shock syndrome. To investigate whether vaccination with a plasmid DNA encoding a non-toxic mutant TSST-1 (mTSST-1) can protect mice against wild-type TSST-1-induced lethal shock, the mice were intranasally immunized with the plasmid DNA (named pcDNA-mTSST-1) plus a mucosal adjuvant, a non-toxic mutant labile toxin (mLT). After the immunization, the mice were challenged with TSST-1 and lipopolysaccharide (LPS). The survival rate of mice immunized with pcDNA-mTSST-1 plus mLT was higher than that of the control mice immunized with PBS alone, mLT alone, pcDNA-mTSST-1 alone, or a parent plasmid plus mLT. The titers of interferon-? (IFN-?) in the sera of mice immunized with pcDNA-mTSST-1 plus mLT were significantly lower than those of the mLT control mice. Immunization with pcDNA-mTSST-1 plus mLT increased the serum levels of TSST-1-specific antibodies, especially immunoglobulin G1 (IgG1) and IgG2a subclasses. Furthermore, the sera obtained from mice immunized with pcDNA-mTSST-1 plus mLT significantly inhibited the TSST-1-induced secretion of IFN-? and tumor necrosis factor-? (TNF-?) in murine spleen cells in vitro. These results indicate that immunization with pcDNA-mTSST-1 plus mLT provides protection against the lethal toxic shock of mice induced by wild-type TSST-1. The protective effect could be due to TSST-1-specific neutralizing antibodies as well as the inhibition of IFN-? and TNF-? secretions. Since TSST-1 is commonly released by invasive S. aureus, the pcDNA-mTSST-1 should be useful in preventing toxin-induced shock resulting from S. aureus infection.
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The expression of malarial invasion-related molecules is affected by two different nitric oxide-based treatments.
Folia Parasitol.
PUBLISHED: 08-20-2013
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The host immune response to parasitic infections plays an important role in controlling multiplication of the parasite and reducing clinical symptoms and life-threatening complications. Nitric oxide (NO), an important innate immune factor and classic Th1 immune effector, may play a role in inhibiting plasmodium infection. In this study, we used two different approaches (L-Arginine [precursor of NO] and NOC5 [short-time NO donor]) to prove the roles of NO in malaria infection. We used 6-8 week-old female BALB/c mice infected with the rodent malaria Plasmodium yoelii Landau, Michel et Adam, 1968 - strain 17XL (P.y17XL) as a model. For L-Arg treatment, mice were administered with an oral dose of 1.5 mg/g L-Arg daily for seven consecutive days prior to infection with Py17XL. L-Arg pretreatment resulted in the decrease of the mRNA level of the apical membrane antigen 1 (AMA1) gene, which encodes a protein involved in host invasion. For NOC5 treatment, NOC5 was injected intraperitoneally into the P.y17XL infected mice on day 5 post-infection or incubated in vitro with purified Py17XL schizonts. Both in vivo and in vitro treatments with NOC5 led to down-regulation of the transcript and protein levels of invasion-related molecules (AMA1, merozoites surface protein 1 and Py235). Our results confirmed the protective role of NO in the asexual blood stage of parasitic infection, which may be partially due to reduced expression of parasite invasion molecules.
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Broadband all-dielectric magnifying lens for far-field high-resolution imaging.
Adv. Mater. Weinheim
PUBLISHED: 08-06-2013
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A transformation-optics magnifying lens is reported in the microwave frequency, which is made of inhomogeneous but isotropic dielectrics to reach impedance matching. The authors demonstrate the broadband subwavelength imaging performance and magnification factor experimentally from the far-field radiation patterns.
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BmCREC is an endoplasmic reticulum (ER) resident protein and required for ER/Golgi morphology.
J. Biol. Chem.
PUBLISHED: 08-06-2013
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Silkworm posterior silkgland is a model for studying intracellular trafficking. Here, using this model, we identify several potential cargo proteins of BmKinesin-1 and focus on one candidate, BmCREC. BmCREC (also known as Bombyx mori DNA supercoiling factor, BmSCF) was previously proposed to supercoil DNA in the nucleus. However, we show here that BmCREC is localized in the ER lumen. Its C-terminal tetrapeptide HDEF is recognized by the KDEL receptor, and subsequently it is retrogradely transported by coat protein I (COPI) vesicles to the ER. Lacking the HDEF tetrapeptide of BmCREC or knocking down COPI subunits results in decreased ER retention and simultaneously increased secretion of BmCREC. Furthermore, we find that BmCREC knockdown markedly disrupts the morphology of the ER and Golgi apparatus and leads to a defect of posterior silkgland tube expansion. Together, our results clarify the ER retention mechanism of BmCREC and reveal that BmCREC is indispensable for maintaining ER/Golgi morphology.
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A photoelectrochemical immunosensor for tris(2,3-dibromopropyl) isocyanurate detection with a multiple hybrid CdTe/Au-TiO2 nanotube arrays.
Analyst
PUBLISHED: 08-01-2013
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In this paper, tris(2,3-dibromopropyl) isocyanurate (TBC) is for the first time as far as we know determined by ultrasensitive photoelectrochemical (PEC) immunoassay using an antibody-modified ternary hybrid CdTe/Au-TiO2 nanotube arrays (NTAs) photoelectrode, developed by the pulse electrodeposition technique. The as-prepared hybrid shows enhanced photon absorption and photocurrent response, which subsequently increased the photoelectrical conversion efficiency in the visible region. TBC-antibody (Ab) was developed in rabbits as a result of immunization with the BSA-TBC conjugate and covalently cross-linked onto the CdTe/Au-TiO2 NTAs. Since the photocurrent is highly dependent on the TiO2 surface properties, the specific interaction between TBC and the antibody results in a sensitive change in the photocurrent, which displayed a linear range of 5.0 × 10(-11) to 5.0 × 10(-5) M and a low detection limit of 5.0 × 10(-11) M for TBC determination. This proposed strategy highlights the application of TiO2 nanotube in visible-light-activated photoelectrochemical biosensing, which could largely reduce the destructive effect of UV light on biomolecules.
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Serum metabolic signatures of four types of human arthritis.
J. Proteome Res.
PUBLISHED: 07-12-2013
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Similar symptoms of the different types of arthritis have continued to confound the clinical diagnosis and represent a clinical dilemma making treatment choices with a more personalized or generalized approach. Here we report a mass spectrometry-based metabolic phenotyping study to identify the global metabolic defects associated with arthritis as well as metabolic signatures of four major types of arthritis--rheumatoid arthritis (n = 27), osteoarthritis (n = 27), ankylosing spondylitis (n = 27), and gout (n = 33)--compared with healthy control subjects (n = 60). A total of 196 metabolites were identified from serum samples using a combined gas chromatography coupled with time-of-flight mass spectrometry (GC-TOF MS) and ultraperformance liquid chromatography quadrupole-time-of-flight mass spectrometry (UPLC-QTOF MS). A global metabolic profile is identified from all arthritic patients, suggesting that there are common metabolic defects resulting from joint inflammation and lesion. Meanwhile, differentially expressed serum metabolites are identified constituting an unique metabolic signature of each type of arthritis that can be used as biomarkers for diagnosis and patient stratification. The results highlight the applicability of metabonomic phenotyping as a novel diagnostic tool for arthritis complementary to existing clinical modalities.
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[Predictive model for post-treatment tooth loss of patients with aggressive periodontitis].
Beijing Da Xue Xue Bao
PUBLISHED: 06-19-2013
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To establish a predictive model for long-term tooth loss of patients with aggressive periodontitis (AgP) after periodontal treatment.
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Acupuncture and moxibustion for inflammatory bowel diseases: a systematic review and meta-analysis of randomized controlled trials.
Evid Based Complement Alternat Med
PUBLISHED: 06-08-2013
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Background. Inflammatory bowel diseases (IBD) are recurrent and refractory which include ulcerative colitis (UC) and Crohns disease (CD). Clinical researches about acupuncture and moxibustion treatments for IBD are increasing, while systematic reviews about their efficacy remains in a shortage. This study sought to evaluate the efficacy of acupuncture and moxibustion for IBD. Methods. Seven significant databases both in and abroad were searched for randomized controlled trials (RCTs) which compared acupuncture and moxibustion as the main intervention to pharmacotherapy in treating IBD. A meta-analysis was performed. Results. A total of 43 RCTs were included. Among the 43 included trials, 10 trials compared oral sulphasalazine (SASP) with acupuncture and/or moxibustion treatments. A meta-analysis of the 10 trials indicated that acupuncture and moxibustion therapy was superior to oral SASP. Conclusion. Acupuncture and moxibustion therapy demonstrates better efficacy than oral SASP in treating IBD. However, given the limitations of this systematic review and the included literature, definitive conclusions regarding the exact efficacy of acupuncture and moxibustion treatment for IBD cannot be drawn. Extant RCTs still cannot provide sufficient evidence and multicentre, double-blind RCTs with large sample sizes are needed to provide higher-quality evidence.
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Experimental far-field imaging properties of a ~5-?m diameter spherical lens.
Opt Lett
PUBLISHED: 06-01-2013
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Microscale lenses are mostly used as near-sighted lenses. The far-field imaging properties of a microscale spherical lens, where the lens is spatially separated from the object, are experimentally studied. Our experimental results show that, for a blu-ray disc (an object) whose spacing is 300 nm, the lens can magnify the stripe patterns of the disc when the lens is spatially separated from the object. In the experimentally tested range (0-14 ?m), all the magnified images are virtual images. When the distance is increased from 0 to 14 ?m the magnification decreases from 1.47× to 1.20× and the field of view increases from 3.8 to 12.2 ?m. The image magnification cannot be described by standard geometrical optics.
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[Research progress on photosynthesis regulating and controlling soil respiration].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 05-31-2013
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To understand the mechanisms of soil respiration and accurately estimate its magnitude are the crucial basis of evaluating global carbon balance. However, the previously built soil respiration forecast models usually neglect the physiological processes that photosynthesis supplies substrates for rhizospheric respiration, leading to the defect in evaluating the mechanisms of soil respiration. This paper summarized the research progress on the mechanisms of photosynthetic regulation and control of soil respiration, introduced the related main research methods, and discussed the existing problems and research hotspots.
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Computational pharmacological comparison of Salvia miltiorrhiza and Panax notoginseng used in the therapy of cardiovascular diseases.
Exp Ther Med
PUBLISHED: 05-06-2013
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The herb pair comprising Salvia miltiorrhiza (SM) and Panax notoginseng (PN) has been used as a classical formula for cardiovascular diseases (CVDs) in China and in western countries. However, the pharmacology of SM and PN in this herb pair has not been fully elucidated. The aim of this study was to compare the mechanisms of SM and PN at the molecular level for the treatment of CVDs. We used a systems pharmacology approach, integrating ligand clustering, chemical space, docking simulation and network analysis, to investigate these two herbal medicines. The compounds in SM were attached to clusters 2, 3, 5, 6, 8 and 9, while the compounds in PN were attached to clusters 1, 2, 4, 5, 6, 7, 8 and 10. The distributions of chemical space between the compounds from SM and PN were discrete, with the existence of small portions of overlap, and the majority of the compounds did not violate Lipinskis rule of five. Docking indicated that the average number of targets correlated with each compound in SM and PN were 5.0 and 3.6, respectively. The minority nodes in the SM and PN drug-target networks possessed common values of betweenness centrality, closeness centrality, topological coefficients and shortest path length. Furthermore, network analyses revealed that SM and PN exerted different modes of action between compounds and targets. These results suggest that the method of computational pharmacology is able to intuitively trace out the similarities and differences of two herbs and their interaction with targets from the molecular level, and that the combination of two herbs may extend their activities in different potential multidrug combination therapies for CVDs.
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Multivalent scaffold proteins as superagonists of TRAIL receptor 2-induced apoptosis.
Mol. Cancer Ther.
PUBLISHED: 05-03-2013
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Activation of TNF-related apoptosis-inducing ligand receptor 2 (TRAILR2) can induce apoptosis in a variety of human cancer cell lines and xenografts, while lacking toxicity in normal cells. The natural ligand and agonistic antibodies show antitumor activity in preclinical models of cancer, and this had led to significant excitement in the clinical potential of these agents. Unfortunately, this optimism has been tempered by trial data that, thus far, are not showing clear signs of efficacy in cancer patients. The reasons for discrepant preclinical and clinical observations are not understood, but one possibility is that the current TRAILR2 agonists lack sufficient potency to achieve a meaningful response in patients. Toward addressing that possibility, we have developed multivalent forms of a new binding scaffold (Tn3) that are superagonists of TRAILR2 and can induce apoptosis in tumor cell lines at subpicomolar concentrations. The monomer Tn3 unit was a fibronectin type III domain engineered for high-affinity TRAILR2 binding. Multivalent presentation of this basic unit induced cell death in TRAILR2-expressing cell lines. Optimization of binding affinity, molecular format, and valency contributed to cumulative enhancements of agonistic activity. An optimized multivalent agonist consisting of 8 tandem Tn3 repeats was highly potent in triggering cell death in TRAIL-sensitive cell lines and was 1 to 2 orders of magnitude more potent than TRAIL. Enhanced potency was also observed in vivo in a tumor xenograft setting. The TRAILR2 superagonists described here have the potential for superior clinical activity in settings insensitive to the current therapeutic agonists that target this pathway.
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The morphological and settling properties of ANAMMOX granular sludge in high-rate reactors.
Bioresour. Technol.
PUBLISHED: 04-19-2013
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Digital macro photography and settling tests were carried out to investigate the morphological and settling characteristics of ANAMMOX granules in a high-rate reactor. The ANAMMOX granules could be divided into settling and floating granules. The settling granules with an average diameter of 2.96±0.99 mm were smaller than the floating granules with an average diameter of 4.58±1.22 mm. A settling model was established and validated to correlate the settling velocity with the density (?G), mass shape factor (?mass), shape-correction factor (characterized by sphericity (?()) or roundness (?)) and projected area equivalent sphere diameter (dP) of ANAMMOX granules. The sphericity was more suitable than the roundness for describing the settling behavior. The sensitivity of four parameters was in the order of ?G,?mass, dP and ?(). Based on the settling model, ANAMMOX granules with diameter of 1.75-4.00 mm were supposed to be optimal for the ANAMMOX process.
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iTRAQ protein profile analysis of Citrus sinensis roots in response to long-term boron-deficiency.
J Proteomics
PUBLISHED: 04-09-2013
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Seedlings of Citrus sinensis were fertilized with boron (B)-deficient (0?M H3BO3) or -sufficient (10?M H3BO3) nutrient solution for 15weeks. Thereafter, iTRAQ analysis was employed to compare the abundances of proteins from B-deficient and -sufficient roots. In B-deficient roots, 164 up-regulated and 225 down-regulated proteins were identified. These proteins were grouped into the following functional categories: protein metabolism, nucleic acid metabolism, stress responses, carbohydrate and energy metabolism, cell transport, cell wall and cytoskeleton metabolism, biological regulation and signal transduction, and lipid metabolism. The adaptive responses of roots to B-deficiency might include following several aspects: (a) decreasing root respiration; (b) improving the total ability to scavenge reactive oxygen species (ROS); and (c) enhancing cell transport. The differentially expressed proteins identified by iTRAQ are much larger than those detected using 2D gel electrophoresis, and many novel B-deficiency-responsive proteins involved in cell transport, biological regulation and signal transduction, stress responses and other metabolic processes were identified in this work. Our results indicate remarkable metabolic flexibility of citrus roots, which may contribute to the survival of B-deficient plants. This represents the most comprehensive analysis of protein profiles in response to B-deficiency.
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The competition between template growth and catalytic growth of one-dimensional ZnS nanostructures: nanobelts or nanowires.
Dalton Trans
PUBLISHED: 04-04-2013
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Template growth and catalytic growth are two typical mechanisms for the solution-chemistry synthesis of one-dimensional (1D) II-VI semiconductor nanomaterials. Here, we systematically demonstrate the competition relationship between them by tuning the synthesis of 1D ZnS nanostructures in different chain-length primary alkyl-amines. The template growth, derived from the coordination effect of amines, produces ZnS nanobelts and will compete with the Ag2S-catalyzed mechanism as AgNO3 is added into these amines. In short-chain n-propylamine and n-butylamine the template growth is much stronger than the catalytic growth, leading to the morphology maintenance of ZnS nanobelts, whereas the latter replaces the former in long-chain n-octylamine and n-dodecylamine due to the decrease of coordination ability of amines, which yields ZnS nanowires instead of nanobelts. A balance of competition is built between these two mechanisms in middle-length n-hexylamine, producing a mixture of ZnS nanobelts and nanowires. The morphology and growth mechanism changes of ZnS nanostructures have been rationally investigated using various characterization techniques. Meanwhile, the optical properties of the products synthesized before and after adding AgNO3 are comparatively studied by UV-vis absorption and photoluminescence (PL) spectra.
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Association of rs10954213 polymorphisms and haplotype diversity in interferon regulatory factor 5 with systemic lupus erythematosus: a meta-analysis.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 02-08-2013
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The rs10954213 polymorphism and the haplotype diversity in interferon regulatory factor 5 (IRF5) play a special role in systemic lupus erythematosus (SLE) but with inconclusive results. We conducted a meta-analysis integrating case-control and haplotype variant studies in multiple ethnic populations to clearly discern the effect of these two variants on SLE. Eleven studies on the relation between rs10954213 polymorpisms in IRF5 and SLE were included and we selected a random effect model to calculate the pooled odds ratios (ORs) and the corresponding 95% confidence interval (95% CI). A total of 6982 cases and 8077 controls were involved in the meta-analysis. The pooled results indicated that A allele was significantly associated with increased risk of SLE as compared with the IRF5 rs10954213 G allele (A vs. G, P<0.00001) in all subjects. The same pattern of the results was also obtained in the European, African American, and Latin American. Asian population had a much lower prevalence of the A allele (49.1%) than any other population studied, and Europeans had the highest frequency of the IRF5 rs10954213 A allele (62.1%). The significant association of increased SLE risk and TCA haplotype was indicated in the contrast of TCA vs. TTA as the pooled OR was 2.14 (P=0.002). The same result was also found in the contrast of TCA vs. TTG as the pooled OR was 1.45 (P=0.004). This meta-analysis suggests that the A allele of rs10954213 and TCA haplotype (rs2004640-rs2070197-rs10954213) in IRF5 is associated with the increased risk of SLE in different ethnic groups, and its prevalence is ethnicity dependent.
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Network pharmacology-based prediction of the multi-target capabilities of the compounds in Taohong Siwu decoction, and their application in osteoarthritis.
Exp Ther Med
PUBLISHED: 02-06-2013
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Taohong Siwu decoction (THSWD), a formulation prescribed in traditional Chinese medicine (TCM), has been widely used in the treatment of osteoarthritis (OA). TCM has the potential to prevent diseases, such as OA, in an integrative and holistic manner. However, the system-level characterization of the drug-target interactions of THSWD has not been elucidated. In the present study, we constructed a novel modeling system, by integrating chemical space, virtual screening and network pharmacology, to investigate the molecular mechanism of action of THSWD. The chemical distribution of the ligand database and the potential compound prediction demonstrated that THSWD, as a natural combinatorial chemical library, comprises abundant drug-like and lead-like compounds that may act as potential inhibitors for a number of important target proteins associated with OA. Moreover, the results of the compound-target network analysis demonstrated that 19 compounds within THSWD were correlated with more than one target, whilst the maximum degree of correlation for the compounds was seven. Furthermore, the target-disease network indicated that THSWD may potentially be effective against 69 diseases. These results may aid in the understanding of the use of THSWD as a multi-target therapy in OA. Moreover, they may be useful in establishing other pharmacological effects that may be brought about by THSWD. The in silico method used in this study has the potential to advance the understanding of the molecular mechanisms of TCM.
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PPAR-? agonist pioglitazone prevents apoptosis of endothelial progenitor cells from rat bone marrow.
Cell Biol. Int.
PUBLISHED: 01-06-2013
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Selective peroxisome proliferator-activated receptor-? (PPAR-?) agonist affects the functions of endothelial progenitor cells (EPCs). This study explores the effect of selective PPAR-? agonist, pioglitazone, on EPC apoptosis. The cells were cultured and identified via the double staining method in a medium containing different concentrations of pioglitazone. EPC apoptosis was detected by flow cytometry. On Day 7, EPCs engulfed DiL-ac-LDL and FITC-UEA-1, and showed yellow fluorescence in a laser-scanning confocal microscope. EPC apoptosis inhibition was maximal at 50?µmol/L. The ability of pioglitazone to prevent EPC apoptosis may be mediated by the PI3K/Akt signal pathway. The use of thiazolidine two ketone (TZD) to reduce EPC apoptosis may have some potential in treating vascular diseases.
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Effect of Change in Spindle Structure on Proliferation Inhibition of Osteosarcoma Cells and Osteoblast under Simulated Microgravity during Incubation in Rotating Bioreactor.
PLoS ONE
PUBLISHED: 01-01-2013
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In order to study the effect of microgravity on the proliferation of mammalian osteosarcoma cells and osteoblasts, the changes in cell proliferation, spindle structure, expression of MAD2 or BUB1, and effect of MAD2 or BUB1 on the inhibition of cell proliferation is investigated by keeping mammalian osteosarcoma cells and osteoblasts under simulated microgravity in a rotating wall vessel (2D-RWVS) bioreactor. Experimental results indicate that the effect of microgravity on proliferation inhibition, incidence of multipolar spindles, and expression of MAD2 or BUB1 increases with the extension of treatment time. And multipolar cells enter mitosis after MAD2 or BUB1 is knocked down, which leads to the decrease in DNA content, and decrease the accumulation of cells within multipolar spindles. It can therefore be concluded that simulated microgravity can alter the structure of spindle microtubules, and stimulate the formation of multipolar spindles together with multicentrosomes, which causes the overexpression of SAC proteins to block the abnormal cells in metaphase, thereby inhibiting cell proliferation. By clarifying the relationship between cell proliferation inhibition, spindle structure and SAC changes under simulated microgravity, the molecular mechanism and morphology basis of proliferation inhibition induced by microgravity is revealed, which will give experiment and theoretical evidence for the mechanism of space bone loss and some other space medicine problems.
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Comprehensive analysis of genic male sterility-related genes in Brassica rapa using a newly developed Br300K oligomeric chip.
PLoS ONE
PUBLISHED: 01-01-2013
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To identify genes associated with genic male sterility (GMS) that could be useful for hybrid breeding in Chinese cabbage (Brassicarapa ssp. pekinensis), floral bud transcriptome analysis was carried out using a B. rapa microarray with 300,000 probes (Br300K). Among 47,548 clones deposited on a Br300K microarray with seven probes of 60 nt length within the 3 150 bp region, a total of 10,622 genes were differentially expressed between fertile and sterile floral buds; 4,774 and 5,848 genes were up-regulated over 2-fold in fertile and sterile buds, respectively. However, the expression of 1,413 and 199 genes showed fertile and sterile bud-specific features, respectively. Genes expressed specifically in fertile buds, possibly GMS-related genes, included homologs of several Arabidopsis male sterility-related genes, genes associated with the cell wall and synthesis of its surface proteins, pollen wall and coat components, signaling components, and nutrient supplies. However, most early genes for pollen development, genes for primexine and callose formation, and genes for pollen maturation and anther dehiscence showed no difference in expression between fertile and sterile buds. Some of the known genes associated with Arabidopsis pollen development showed similar expression patterns to those seen in this study, while others did not. BrbHLH89 and BrMYP99 are putative GMS genes. Additionally, 17 novel genes identified only in B. rapa were specifically and highly expressed only in fertile buds, implying the possible involvement in male fertility. All data suggest that Chinese cabbage GMS might be controlled by genes acting in post-meiotic tapetal development that are different from those known to be associated with Arabidopsis male sterility.
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Evidence for multiple distinct interactions between hepatitis B virus P protein and its cognate RNA encapsidation signal during initiation of reverse transcription.
PLoS ONE
PUBLISHED: 01-01-2013
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Replication of hepatitis B virus (HBV) via protein-primed reverse transcription is initiated by binding of the viral P protein to the conserved ? stem-loop on the pregenomic (pg) RNA. This triggers encapsidation of the complex and the ?-templated synthesis of a short P protein-linked DNA oligonucleotide (priming) for subsequent minus-strand DNA extension. ? consists of a lower and upper stem, a bulge containing the priming template, and an apical loop. The nonhelical subelements are considered important for DNA synthesis and pgRNA packaging whereas the role of the upper stem is not well characterized. Priming itself could until recently not be addressed because in vitro generated HBV P - ? complexes showed no activity. Focussing on the four A residues at the base and tip of the upper ? stem and the two U residues in the loop we first investigated the impact of 24 mutations on viral DNA accumulation in transfected cells. While surprisingly many mutations were tolerated, further analyzing the negatively acting mutations, including in a new cell-free priming system, revealed divergent position-related impacts on pgRNA packaging, priming activity and possibly initiation site selection. This genetic separability implies that the ? RNA undergoes multiple distinct interactions with P protein as pgRNA encapsidation and replication initiation progress, and that the strict conservation of ? in nature may reflect its optimal adaptation to comply with all of them. The data further define the most attractive mutants for future studies, including as decoys for interference with HBV replication.
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[A short-term clinical evaluation of periodontal treatment with an Er:YAG laser for patients with chronic periodontitis: a split-mouth controlled study].
Beijing Da Xue Xue Bao
PUBLISHED: 12-20-2011
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To compare the short-term clinical effects following non-surgical periodontal treatment with Er:YAG laser or with combination of ultrasonic subgingival scaling and root planing with hand instrument (SRP) for patients with chronic periodontitis.
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A coordination complex system for generic, ultrafast, and sensitive multimode fluorescent staining of biomolecules.
Inorg Chem
PUBLISHED: 12-06-2011
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Gel electrophoresis staining methodologies documented thus far are largely utilized in a biomolecule context-dependent manner. We report herein the development of a generic, ultrafast, and sensitive multimode fluorescent system for the efficient identification of DNA, RNA, and proteins. Interaction between a positively charged, planar ligand-based coordination complex with partner biomolecule leads to aggregation-induced fluorescence quenching and allows for the image contrast generation within one minute. Alternatively, successive reactions of the biomolecule-loaded gel with cation and ligand, in either order of sequence, provide an equally effective staining efficacy. Image contrast reversal is accomplished through a facile washing or photobleaching procedure. The versatility in the applicable target species and signal generation modes provides a hint at the design of novel staining structures and potentially enables the high-throughput readout of biomolecules.
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Metal ion detection with oligo(ethylene glycol) monolayer-modified gold nanoparticles.
J Nanosci Nanotechnol
PUBLISHED: 11-15-2011
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Two colorimetric sensors of gold nanoparticles (AuNPs) modified with different oligo(ethylene glycol)-containing organic molecules have been developed to detect metal ions by ultraviolet-visible (UV-vis) extinction spectroscopy. These sensors display different responses to some metal ions. One exhibits high selectivity for Hg2+ over a variety of competitive metal ions and the other one can respond to a multitude of metal ions. These differences might result from the different functionalized end groups of the modified molecules. Coordination effect, pH response, and ionic strength were investigated to understand the mechanism of the responses to metal ions. The results suggested that the colorimetric responses were mainly induced by the coordination effect of the modified organic molecules and the removing of the modified organic molecules caused by metal ions.
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Unusual visible luminescence of aluminium polyoxocations in aqueous solution.
Chem. Commun. (Camb.)
PUBLISHED: 11-01-2011
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Identification of aluminium polyoxocations, MO(4)Al(12)(OH)(24)(H(2)O)(12)(7/8+) (M = Al, Ga and Ge) (K-MAl(12)) and Al(30)O(8)(OH)(56)(H(2)O)(26)(18+) (Al(30)), by their luminescence is reported. The fluorescence behavior of K-Al(13) has been found to differ with different metal ions and anions, implying a new discovery of a potential ion sensor.
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[Synthesis and luminescence properties of Y10W2O21:Eu nanophosphor].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 10-31-2011
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In the present paper, a novel nanophosphor, Y10W2O21:Eu was synthesized through a simple and low-cost method: co-precipitation. The results of XRD show that resultant samples are Orthorhombic phase and primitive lattice. The average crystallographic sizes could be confirmed to be approximately 80 nm by means of the Scherrer formula, which are in good agreement with the particles sizes exhibited by SEM. In the excitation spectra of Y10W2O21:Eu nanophosphor, by monitoring 610 nm, the charge transfer bands (CTB) of O--Eu and O--W, centering at around 270 and 307 nm, can be observed, respectively. The spectral lines shape and locations of excitation peak corresponding to 4f-->4f transitions are similar in all samples. But the relative intensity ratios between O--Eu and O--W CTB excitation peak increase with the Eu3+ doping concentration increasing. The characteristic red emission at around 610 nm of Eu3+ was also observed, ascribed to the (5)D0--(7)>F2 transition of Eu3+, and the optimal doping concentration is 20 mol%. Finally, the transition intensity parameters omega(lamda = 2,4) and the quantum efficiencies of (5)D0 level of Eu3+ were calculated according to Judd-Ofelt theory. The results indicate that Eu(3+5)D0-->(7)F2 610 nm red luminescence can be effectively excited by 394 nm near-UV light and 464 nm blue light in Y10W2O21 host, which is similar to the familiar Eu3+ doped tungstate (e.g., Gd2(WO4)3, CaWO4). Therefore, the Y10W2O21:Eu red nanophosphors may have a potential application for white LED.
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[Spatiotemporal changes of potential evapotranspiration in Songnen Plain of Northeast China].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 10-20-2011
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Based on the daily meteorological data from 72 weather stations from 1961-2003, a quantitative analysis was conducted on the spatiotemporal changes of the potential evapotranspiration in the Plain. The Penman-Monteith model was applied to calculate the potential evapotranspiration; the Mann-Kendall test, accumulative departure curve, and climatic change rate were adopted to analyze the change trend of the evapotranspiration; and the spatial analysis function of ArcGIS was used to detect the spatial distribution of the evapotranspiration. In 1961-2003, the mean annual potential evapotranspiration in the Plain was 330 - 860 mm, and presented an overall decreasing trend, with the high value appeared in southwest region, low value in surrounding areas of southwest region, and a ring-belt increasing southwestward. The climatic change rate of the annual potential evapotranspiration was -0.21 mm x a(-1). The annual potential evapotranspiration was the highest in 1982, the lowest in 1995, and increased thereafter. Seasonally, the climatic change rate of the potential evapotranspiration in spring, summer, autumn, and winter was -0.19, 0.01, -0.05, and 0.03 mm x a(-1), respectively, suggesting that the potential evapotranspiration had a weak increase in winter and summer and a slight decrease in spring and autumn.
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[Surface plasmon resonance sensor working at terahertz frequency].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 10-20-2011
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The authors provided an analysis of the surface plasmon resonance sensor (SPRS) working at terahertz (THz) frequency with angular modulation and made a brief comparison between optical SPRS and THz-SPRS. At optical frequency, there is a dip in the angular reflection spectrum due to the resonant transfer of the energy carried by the incident light wave to surface plasmon, while there is an enhanced reflection peak at the terahertz frequency. The position of the peak is solely determined by the refractive indices of the prism and the sample, and independent of the properties of the metal film. Our results show that the determination of the dielectric constant of a sample in the THz SPRS is much simpler than its optical counterpart. Taking into account of the importance of THz technology applying in biological and medical field, the authors device may provide a valuable method for bio-sensing and analysis.
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