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Find video protocols related to scientific articles indexed in Pubmed.
[Heparin attenuates lipopolysaccharide-induced acute lung injury by inhibiting nitric oxide synthase and transforming growth factor -?/Smad signaling pathway].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 11-18-2014
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To investigate whether heparin has a beneficial effect on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in rats, and to explore the possible underlying mechanisms.
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Outcomes of adjuvant endocrine therapy and hormone receptor status change following neoadjuvant chemotherapy in breast cancer patients.
Int. J. Biol. Markers
PUBLISHED: 11-05-2014
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This retrospective study investigated the therapeutic benefit of adjuvant endocrine therapy (ET) in breast cancer patients with hormone receptor (HR) status change from positive to negative after neoadjuvant chemotherapy (NAC).
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[The effect of hypoxia on proliferation and osteogenic differentiation of periodontal ligament cells].
Shanghai Kou Qiang Yi Xue
PUBLISHED: 10-24-2014
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To investigate the effect of hypoxia on proliferation and osteogenic differentiation of periodontal ligament cells (PDLCs) in vitro.
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Ion permeation in K? channels occurs by direct Coulomb knock-on.
Science
PUBLISHED: 10-18-2014
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Potassium channels selectively conduct K(+) ions across cellular membranes with extraordinary efficiency. Their selectivity filter exhibits four binding sites with approximately equal electron density in crystal structures with high K(+) concentrations, previously thought to reflect a superposition of alternating ion- and water-occupied states. Consequently, cotranslocation of ions with water has become a widely accepted ion conduction mechanism for potassium channels. By analyzing more than 1300 permeation events from molecular dynamics simulations at physiological voltages, we observed instead that permeation occurs via ion-ion contacts between neighboring K(+) ions. Coulomb repulsion between adjacent ions is found to be the key to high-efficiency K(+) conduction. Crystallographic data are consistent with directly neighboring K(+) ions in the selectivity filter, and our model offers an intuitive explanation for the high throughput rates of K(+) channels.
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Highly diastereo- and enantioselective copper-catalyzed propargylic alkylation of acyclic ketone enamines for the construction of two vicinal stereocenters.
Chem. Commun. (Camb.)
PUBLISHED: 10-11-2014
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The first highly diastereo- and enantioselective propargylic alkylation of acyclic ketone enamines to form vicinal tertiary stereocenters has been reported by employing copper catalysis in combination with a bulky and structurally rigid tridentate ketimine P,N,N-ligand.
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cDNA-AFLP analysis reveals the adaptive responses of citrus to long-term boron-toxicity.
BMC Plant Biol.
PUBLISHED: 09-13-2014
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BackgroundBoron (B)-toxicity is an important disorder in agricultural regions across the world. Seedlings of `Sour pummelo¿ (Citrus grandis) and `Xuegan¿ (Citrus sinensis) were fertigated every other day until drip with 10 ¿M (control) or 400 ¿M (B-toxic) H3BO3 in a complete nutrient solution for 15 weeks. The aims of this study were to elucidate the adaptive mechanisms of citrus plants to B-toxicity and to identify B-tolerant genes.ResultsB-toxicity-induced changes in seedlings growth, leaf CO2 assimilation, pigments, total soluble protein, malondialdehyde (MDA) and phosphorus were less pronounced in C. sinensis than in C. grandis. B concentration was higher in B-toxic C. sinensis leaves than in B-toxic C. grandis ones. Here we successfully used cDNA-AFLP to isolate 67 up-regulated and 65 down-regulated transcript-derived fragments (TDFs) from B-toxic C. grandis leaves, whilst only 31 up-regulated and 37 down-regulated TDFs from B-toxic C. sinensis ones, demonstrating that gene expression is less affected in B-toxic C. sinensis leaves than in B-toxic C. grandis ones. These differentially expressed TDFs were related to signal transduction, carbohydrate and energy metabolism, nucleic acid metabolism, protein and amino acid metabolism, lipid metabolism, cell wall and cytoskeleton modification, stress responses and cell transport. The higher B-tolerance of C. sinensis might be related to the findings that B-toxic C. sinensis leaves had higher expression levels of genes involved in photosynthesis, which might contribute to the higher photosyntheis and light utilization and less excess light energy, and in reactive oxygen species (ROS) scavenging compared to B-toxic C. grandis leaves, thus preventing them from photo-oxidative damage. In addition, B-toxicity-induced alteration in the expression levels of genes encoding inorganic pyrophosphatase 1, AT4G01850 and methionine synthase differed between the two species, which might play a role in the B-tolerance of C. sinensis.Conclusions C. sinensis leaves could tolerate higher level of B than C. grandis ones, thus improving the B-tolerance of C. sinensis plants. Our findings reveal some novel mechanisms on the tolerance of plants to B-toxicity at the gene expression level.
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The complete mitochondrial genome of Tetranychus truncatus Ehara (Acari: Tetranychidae).
Mitochondrial DNA
PUBLISHED: 08-27-2014
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Abstract The complete mitochondrial genome of Tetranychus truncatus Ehara (Acari: Tetranychidae) is a typical circular DNA with length of 13,089?bp (GenBank accession number: KM111296). The genome contains all 13 protein-coding genes (PCGs), an A + T-rich region, two rRNA genes and 22 tRNA genes. The A + T content of the mitochondrial genome is 84.5%. The AT-skew is positive (0.032) while the GC-skew is negative (-0.058). The gene arrangement is conserved in T. urticae, Panonychus citri and P. ulmi which are in the same family (Tetranychidae). The A + T-rich region is only 43?bp in length with high A + T content (97.7%). All the PCGs start with typical ATD codons. Eight PCGs have complete TAA stop codons, while five PCGs have an incomplete stop codon (T).
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Responses of super rice (Oryza sativa L.) to different planting methods for grain yield and nitrogen-use efficiency in the single cropping season.
PLoS ONE
PUBLISHED: 08-11-2014
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To break the yield ceiling of rice production, a super rice project was developed in 1996 to breed rice varieties with super high yield. A two-year experiment was conducted to evaluate yield and nitrogen (N)-use response of super rice to different planting methods in the single cropping season. A total of 17 rice varieties, including 13 super rice and four non-super checks (CK), were grown under three N levels [0 (N0), 150 (N150), and 225 (N225) kg ha-1] and two planting methods [transplanting (TP) and direct-seeding in wet conditions (WDS)]. Grain yield under WDS (7.69 t ha-1) was generally lower than TP (8.58 t ha-1). However, grain yield under different planting methods was affected by N rates as well as variety groups. In both years, there was no difference in grain yield between super and CK varieties at N150, irrespective of planting methods. However, grain yield difference was dramatic in japonica groups at N225, that is, there was an 11.3% and 14.1% average increase in super rice than in CK varieties in WDS and TP, respectively. This suggests that high N input contributes to narrowing the yield gap in super rice varieties, which also indicates that super rice was bred for high fertility conditions. In the japonica group, more N was accumulated in super rice than in CK at N225, but no difference was found between super and CK varieties at N0 and N150. Similar results were also found for N agronomic efficiency. The results suggest that super rice varieties have an advantage for N-use efficiency when high N is applied. The response of super rice was greater under TP than under WDS. The results suggest that the need to further improve agronomic and other management practices to achieve high yield and N-use efficiency for super rice varieties in WDS.
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Continuous hypoxia regulates the osteogenic potential of mesenchymal stem cells in a time-dependent manner.
Mol Med Rep
PUBLISHED: 08-05-2014
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The effects of hypoxia on the osteogenic potential of mesenchymal stem cells (MSCs) have been previously reported. From these studies, possible factors affecting the association between hypoxia and the osteogenic differentiation of MSCs have been suggested, including hypoxia severity, cell origin and methods of induction. The effect of the duration of hypoxia, however, remains poorly understood. The aim of the present study was to investigate the effect of continuous hypoxia on the induced osteogenesis of MSCs. Rat MSCs were isolated and cultured in vitro. Once the cells had been cultured to passage three, they were switched to 1% oxygen and cultured either with or without osteogenic medium, while cells in the control groups were cultured under normoxia in corresponding conditions. Four osteogenic differentiation biomarkers, runt-related transcription factor 2, osteopontin, osteocalcin and alkaline phosphatase, were analyzed by quantitative polymerase chain reaction and western blotting at defined intervals throughout the culture period. In addition, Alizarin Red staining was used to assess changes in mineralization. The results showed that 1% hypoxia was able to enhance and accelerate the osteogenic ability of the MSCs during the initial phases of differentiation, and the protein expression of certain associated biomarkers was upregulated. However, continuous hypoxia was shown to impair osteogenesis in the latter stages of differentiation. These findings suggest that hypoxia can regulate the osteogenesis of MSCs in a time-dependent manner.
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Bisphenol a regulates the estrogen receptor alpha signaling in developing hippocampus of male rats through estrogen receptor.
Hippocampus
PUBLISHED: 07-22-2014
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Bisphenol A (BPA), one of the most common environmental endocrine disruptors, has been recognized to have wide adverse effects on the brain development and behavior. These adversities are related to its ability to bind estrogen receptor (ER) with subsequent alteration of its expression in the target areas. However, very little is known about whether BPA exposure also affects ER phosphorylation and its translocation to nucleus during postnatal development, two critical steps for its function. Here, we found that during development from postnatal day 7 (P7) to P21, the alpha subtype of ER (ER?) in the hippocampus of male rats experienced remarkable alterations in terms of its expression, phosphorylation and translocation to nucleus. Exposure to low level of BPA had bidirectional, development-dependent effects on the expression of ER? mRNA and protein, but decreased ER? phosphorylation and impaired its translocation to nucleus throughout the period investigated. Treatment with low dose of ICI 182,780 (ICI), an ER antagonist to block the binding of ER with BPA, reversed the altered ER? following BPA exposure, highlighting critical involvement of ER. Moreover, ICI treatment rescued the hippocampus-dependent behavioral deficits in the adult rats experiencing early-life BPA exposure. Overall, our results indicate that BPA interferes with the ER? signaling in the developing hippocampus in an ER-dependent manner, which may underlie its adverse behavioral and cognitive outcomes in adult animals. © 2014 Wiley Periodicals, Inc.
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Activation of the AT1R/HIF-1 ? /ACE Axis Mediates Angiotensin II-Induced VEGF Synthesis in Mesenchymal Stem Cells.
Biomed Res Int
PUBLISHED: 06-30-2014
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A local renin-angiotensin system (RAS) is expressed in mesenchymal stem cells (MSCs) and regulates stem cell function. The local RAS influences the survival and tissue repairing ability of transplanted stem cells. We have previously reported that angiotensin II (Ang II) pretreatment can significantly increase vascular endothelial growth factor (VEGF) synthesis in MSCs through the ERK1/2 and Akt pathways via the Ang II receptor type 1 (AT1R). However, the role of angiotensin-converting enzyme (ACE) has not been clarified. Furthermore, whether Ang II pretreatment activates hypoxia-inducible factor-1? (HIF-1?) in MSCs has not been elucidated. Our data show that both ACE and HIF-1? are involved in promoting VEGF expression in MSCs, and that both are upregulated by Ang II stimulation. The upregulation of ACE appeared after the rapid degradation of exogenous Ang II, and led to the formation of endogenous Ang II. On the other hand, the ACE inhibitor, captopril, attenuated Ang II-enhanced HIF-1? upregulation, while HIF-1? suppression markedly attenuated ACE expression. This interesting finding suggests an interaction between ACE and HIF-1?. We conclude that Ang II pretreatment, as a trigger, activated the AT1R/HIF-1?/ACE axis that then mediated Ang II-induced VEGF synthesis in MSCs.
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Effects of boron deficiency on major metabolites, key enzymes and gas exchange in leaves and roots of Citrus sinensis seedlings.
Tree Physiol.
PUBLISHED: 06-23-2014
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Boron (B) deficiency is a widespread problem in many crops, including Citrus. The effects of B-deficiency on gas exchange, carbohydrates, organic acids, amino acids, total soluble proteins and phenolics, and the activities of key enzymes involved in organic acid and amino acid metabolism in 'Xuegan' [Citrus sinensis (L.) Osbeck] leaves and roots were investigated. Boron-deficient leaves displayed excessive accumulation of nonstructural carbohydrates and much lower CO2 assimilation, demonstrating feedback inhibition of photosynthesis. Dark respiration, concentrations of most organic acids [i.e., malate, citrate, oxaloacetate (OAA), pyruvate and phosphoenolpyruvate] and activities of enzymes [i.e., phosphoenolpyruvate carboxylase (PEPC), NAD-malate dehydrogenase, NAD-malic enzyme (NAD-ME), NADP-ME, pyruvate kinase (PK), phosphoenolpyruvate phosphatase (PEPP), citrate synthase (CS), aconitase (ACO), NADP-isocitrate dehydrogenase (NADP-IDH) and hexokinase] involved in glycolysis, the tricarboxylic acid (TCA) cycle and the anapleurotic reaction were higher in B-deficient leaves than in controls. Also, total free amino acid (TFAA) concentration and related enzyme [i.e., NADH-dependent glutamate 2-oxoglutarate aminotransferase (NADH-GOGAT) and glutamate OAA transaminase (GOT)] activities were enhanced in B-deficient leaves. By contrast, respiration, concentrations of nonstructural carbohydrates and three organic acids (malate, citrate and pyruvate), and activities of most enzymes [i.e., PEPC, NADP-ME, PK, PEPP, CS, ACO, NAD-isocitrate dehydrogenase, NADP-IDH and hexokinase] involved in glycolysis, the TCA cycle and the anapleurotic reaction, as well as concentration of TFAA and activities of related enzymes (i.e., nitrate reductase, NADH-GOGAT, glutamate pyruvate transaminase and glutamine synthetase) were lower in B-deficient roots than in controls. Interestingly, leaf and root concentration of total phenolics increased, whereas that of total soluble protein decreased, in response to B-deficiency. In conclusion, respiration, organic acid (i.e., glycolysis and the TCA cycle) metabolism, the anapleurotic pathway and amino acid biosynthesis were upregulated in B-deficient leaves with excessive accumulation of carbohydrates to 'consume' the excessive carbon available, but downregulated in B-deficient roots with less accumulation of carbohydrates to maintain the net carbon balance.
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Long-term outcomes following adjuvant endocrine therapy in breast cancer patients with a positive-to-negative change of hormone receptor status following neoadjuvant chemotherapy.
Mol Clin Oncol
PUBLISHED: 05-27-2014
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The aim of the present study was to investigate whether breast cancer patients with changes from positive to negative in the hormone receptor following neoadjuvant chemotherapy (NAC) could benefit from adjuvant endocrine therapy (ET). Between December 2000 and November 2010, 97 eligible patients with a positive-to-negative switch of the hormone receptor status following NAC were identified. All the patients were categorized into two groups on the basis of the administration of ET: 57 ET-administered and 40 ET-naïve patients. Survival analyses were performed to examine the prognostic value of ET administration, as well as other clinical and pathological variables. The administration of ET was associated with a significantly improved disease-free survival (DFS) (P=0.018) in patients with a positive-to-negative switch of the hormone receptor status. The 5-year DFS rates were 77.0 and 55.5% in ET-administered and ET-naïve patients, respectively. The 5-year overall survival (OS) rate for ET-administered was also higher than that of the ET-naïve patients (81.3 vs. 72.7%, P=0.053), but the difference between the two groups did not reach a statistical significance. The present study revealed that patients with the hormone receptor that was altered from positive to negative following NAC benefit from ET, and the hormone receptor status should be evaluated not only in specimens obtained during post-NAC surgery, but also in specimens biopsied prior to NAC.
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Dielectric effect on the photovoltage loss in organic photovoltaic cells.
Adv. Mater. Weinheim
PUBLISHED: 05-02-2014
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The VOC loss in several polymer-fullerene solar cells is determined. Based on these data, a major source of photovoltage loss is attributed to the low dielectric constants of the polymers. Such loss is close to zero if the dielectric constant of the polymer-fullerene blend is close to 5.
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Temporomandibular disorders with skeletal open bite treated with stabilization splint and zygomatic miniplate anchorage: A case report.
Angle Orthod
PUBLISHED: 04-30-2014
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Abstract This case report describes the treatment of a patient with temporomandibular disorder (TMD) and skeletal open bite. First, the patient was treated with a stabilization splint to stabilize the condyles in centric relation and to alleviate TMD signs and symptoms. After making a definitive diagnosis from postsplint records, orthodontic treatment was initiated. Titanium miniplates were placed at bilateral zygomatic buttresses and used as orthodontic anchorage for molar intrusion and distalization. The treatment was completed after 30 months. Satisfactory appearance and function were achieved for this patient.
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Microfluidic generation of chitosan/CpG oligodeoxynucleotide nanoparticles with enhanced cellular uptake and immunostimulatory properties.
Lab Chip
PUBLISHED: 04-15-2014
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Chitosan/cytosine-phosphodiester-guanine oligodeoxynucleotide (CpG ODN) nanoparticles as potential immunostimulatory adjuvants were synthesized by the conventional bulk mixing (BM) method and a novel microfluidic (MF) method. Their size and size distribution, CpG ODN loading efficiency, surface charge, biocompatibility, cellular uptake, and immunostimulatory response were investigated. In the BM method, nanoparticles were synthesized by vortexing a mixture of chitosan solution and CpG ODN2006x3-PD solution. In the MF method, the nanoparticles were synthesized by rapidly mixing a chitosan solution and CpG ODN solution in a poly(dimethylsiloxane) microfluidic device. Our results indicated that particle size and size distribution, CpG ODN loading efficiency, and surface charge could be easily adjusted by using the tuning preparation method and controlling the flow ratio of fluid rates in the different microfluidic channels. Compared with the BM method, the MF method yielded a decrease in particle size and size range, an increase in CpG ODN loading efficiency, and a decrease in surface charge. After the particles were exposed to 293XL-hTLR9 cells, a water-soluble tetrazolium salt assay indicated that the BM and MF-processed nanoparticles had no significant toxicity and were biocompatible. An immunochemical assay indicated that both types of nanoparticles entered 293XL-hTLR9 cells and were located in the endolysosomes. The MF-processed nanoparticles showed much higher cellular uptake efficiency. After the particles were exposed to peripheral blood mononuclear cells, an enzyme-linked immunosorbent assay quantitatively indicated that both types of nanoparticles stimulated the production of interleukin-6 and the MF-processed nanoparticles showed a much stronger immunostimulatory response. These results indicate that the MF method can be used to synthesize nanoparticles with a controllable size and size range for enhancing the biological activity of DNA and other biomolecules.
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[Effect of transforming growth factor beta3, bone morphogenetic protein 2, and dexamethasone on chondrogenic differentiation of rabbit synovial mesenchymal stem cells].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 04-04-2014
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To study the effect of transforming growth factor beta3 (TGF-beta3), bone morphogenetic protein 2 (BMP-2), and dexamethasone (DEX) on the chondrogenic differentiation of rabbit synovial mesenchymal stem cells (SMSCs).
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Facile preparation and thermoelectric properties of Bi?Te? based alloy nanosheet/PEDOT:PSS composite films.
ACS Appl Mater Interfaces
PUBLISHED: 04-04-2014
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Bi2Te3 based alloy nanosheet (NS)/poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) composite films were prepared separately by spin coating and drop casting techniques. The drop cast composite film containing 4.10 wt % Bi2Te3 based alloy NSs showed electrical conductivity as high as 1295.21 S/cm, which is higher than that (753.8 S/cm) of a dimethyl sulfoxide doped PEDOT:PSS film prepared under the same condition and that (850-1250 S/cm) of the Bi2Te3 based alloy bulk material. The composite film also showed a very high power factor value, ?32.26 ?Wm(-1) K(-2). With the content of Bi2Te3 based alloy NSs increasing from 0 to 4.10 wt %, the electrical conductivity and Seebeck coefficient of the composite films increase simultaneously.
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Intrinsic fluctuations of cell migration under different cellular densities.
Soft Matter
PUBLISHED: 03-19-2014
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The motility of the Dictyostelium discoideum (DD) cell is studied by video microscopy when the cells are plated on top of an agar plate at different densities, n. It is found that the fluctuating kinetics of the cells can be divided into two normal directions: the cell's forward-moving direction and its normal direction. Along the forward-moving direction, the slope of the amplitude of fluctuation vs. velocity (R||(v)) increases with n, while along the normal direction the slope of R? is independent of n. Both R|| and R? are functions of the cell speed v. The observed linearity in R?(v) indicated that the amplitude of orientational fluctuation (?) of DD cells is a constant independent of v. The independence of the slope of R?(v) on n indicated that ? is also not affected by cellular interactions. The independence of ? on both v and n suggests that orientational fluctuation originates from the intrinsic property of motion fluctuations in DD.
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Zinc phthalocyanine conjugated with the amino-terminal fragment of urokinase for tumor-targeting photodynamic therapy.
Acta Biomater
PUBLISHED: 03-01-2014
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Photodynamic therapy (PDT) has attracted much interest for the treatment of cancer due to the increased incidence of multidrug resistance and systemic toxicity in conventional chemotherapy. Phthalocyanine (Pc) is one of main classes of photosensitizers for PDT and possesses optimal photophysical and photochemical properties. A higher specificity can ideally be achieved when Pcs are targeted towards tumor-specific receptors, which may also facilitate specific drug delivery. Herein, we develop a simple and unique strategy to prepare a hydrophilic tumor-targeting photosensitizer ATF-ZnPc by covalently coupling zinc phthalocyanine (ZnPc) to the amino-terminal fragment (ATF) of urokinase-type plasminogen activator (uPA), a fragment responsible for uPA receptor (uPAR, a biomarker overexpressed in cancer cells), through the carboxyl groups of ATF. We demonstrate the high efficacy of this tumor-targeting PDT agent for the inhibition of tumor growth both in vitro and in vivo. Our in vivo optical imaging results using H22 tumor-bearing mice show clearly the selective accumulation of ATF-ZnPc in tumor region, thereby revealing the great potential of ATF-ZnPc for clinical applications such as cancer detection and guidance of tumor resection in addition to photodynamic treatment.
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Chronic stress impairs GABAergic control of amygdala through suppressing the tonic GABAA receptor currents.
Mol Brain
PUBLISHED: 02-27-2014
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Chronic stress is generally known to exacerbate the development of numerous neuropsychiatric diseases such as fear and anxiety disorders, which is at least partially due to the disinhibition of amygdala subsequent to the prolonged stress exposure. GABA receptor A (GABAAR) mediates the primary component of inhibition in brain and its activation produces two forms of inhibition: the phasic and tonic inhibition. While both of them are critically engaged in limiting the activity of amygdala, their roles in the amygdala disinhibition subsequent to chronic stress exposure are largely unknown.
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Inflammatory modulation effect of glycopeptide from Ganoderma capense (Lloyd) Teng.
Mediators Inflamm.
PUBLISHED: 02-25-2014
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Glycopeptide from Ganoderma capense (Lloyd) Teng (GCGP) injection is widely used in kinds of immune disorders, but little is known about the molecular mechanisms of how GCGP could interfere with immune cell function. In the present study, we have found that GCGP had inflammatory modulation effects on macrophage cells to maintain NO production and iNOS expression at the normal level. Furthermore, western blot analysis showed that the underlying mechanism of immunomodulatory effect of GCGP involved NF-?B p65 translation, I ?B phosphorylation, and degradation; NF-?B inhibitor assays also confirmed the results. In addition, competition study showed that GCGP could inhibit LPS from binding to macrophage cells. Our data indicates that GCGP, which may share the same receptor(s) expressed by macrophage cells with LPS, exerted immunomodulatory effect in a NF-?B-dependent signaling pathway in macrophages.
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Probucol via inhibition of NHE1 attenuates LPS-accelerated atherosclerosis and promotes plaque stability in vivo.
Exp. Mol. Pathol.
PUBLISHED: 02-23-2014
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Activation of Na(+)/H(+) exchanger 1 (NHE1) by lipopolysaccharide (LPS) via Ca(2+)/calpain is responsible in vascular smooth muscle cell (VSMC) apoptosis and to the process of atherosclerosis. Probucol is a lipid-lowering drug which has an anti-atherosclerosis effect. The mechanism remains poorly understood. Here we hypothesized that probucol via inhibition of NHE1 in VSMCs attenuates LPS-accelerated atherosclerosis and promotes plaque stability. Our results revealed that treatment of VSMCs with LPS increased the NHE1 activity in a time-dependent manner, associated with the increased Ca(2+)i. Probucol inhibited the LPS-induced increase of NHE1 activity in a dose-dependent manner in VSMCs for 24-hour co-incubation, as well as the change of Ca(2+)i. In addition, LPS enhanced the calpain activity. Both probucol and calcium chelation of Ca(2+) abolished the LPS-induced increase of calpain activity. Treatment of VSMCs with LPS reduced the expression of Bcl-2 without altering the mRNA level. Probucol inhibited the LPS-reduced expression of Bcl-2 protein in VSMCs. Animal studies indicated administration of probucol suppressed LPS-accelerated apoptosis, atherosclerosis and plaque instability in Apoe(-/-) mice. In conclusion, probucol via inhibition of NHE1 attenuates atherosclerosis lesion growth and promotes plaque stability.
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EphB4 regulates the growth and migration of pancreatic cancer cells.
Tumour Biol.
PUBLISHED: 02-11-2014
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Pancreatic cancer is a serious threat to human life. Moreover, its treatment is complicated and its prognosis is very poor. Therefore, a new method for the diagnosis and treatment of pancreatic cancer is very essential. In this study, a eukaryotic expression plasmid targeting EphB4 was constructed and transfected into PANC-1 pancreatic cancer cells to investigate the inhibition of cell growth and the progression of iRNA against EphB4. This study provides the basis for the gene therapy of pancreatic cancer. The recombinant eukaryotic EphB4 expression plasmid, pSIREN-RetroQ-ZsGreen-EphB4 and a negative control plasmid, pSIREN-RetroQ-ZsGreen-N, were constructed. At 48 h after transfection, the relative messenger RNA (mRNA) and protein levels of EphB4 were measured by RT-PCR and western blot. The proliferation of the transfected cells was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, while cell migration ability was analyzed using the scratch migration assay. At 48 h after transient transfection, EphB4 mRNA expression was significantly decreased in transfected PANC-1 cells as compared to the control group (P < 0.01). In vitro, inhibition of EphB4 expression weakened the proliferation and cell migration ability of PANC-1 cells compared to the control group. The small interfering RNA (siRNA) eukaryotic expression plasmid vector targeting EphB4 was successfully constructed and effectively transfected into PANC-1 cells. The recombinant plasmid can inhibit the expression of EphB4 mRNA and protein in PANC-1 cells, as well as cell growth and migration.
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Fiber-based wearable electronics: a review of materials, fabrication, devices, and applications.
Adv. Mater. Weinheim
PUBLISHED: 02-10-2014
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Fiber-based structures are highly desirable for wearable electronics that are expected to be light-weight, long-lasting, flexible, and conformable. Many fibrous structures have been manufactured by well-established lost-effective textile processing technologies, normally at ambient conditions. The advancement of nanotechnology has made it feasible to build electronic devices directly on the surface or inside of single fibers, which have typical thickness of several to tens microns. However, imparting electronic functions to porous, highly deformable and three-dimensional fiber assemblies and maintaining them during wear represent great challenges from both views of fundamental understanding and practical implementation. This article attempts to critically review the current state-of-arts with respect to materials, fabrication techniques, and structural design of devices as well as applications of the fiber-based wearable electronic products. In addition, this review elaborates the performance requirements of the fiber-based wearable electronic products, especially regarding the correlation among materials, fiber/textile structures and electronic as well as mechanical functionalities of fiber-based electronic devices. Finally, discussions will be presented regarding to limitations of current materials, fabrication techniques, devices concerning manufacturability and performance as well as scientific understanding that must be improved prior to their wide adoption.
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Numerical manifold method for the forced vibration of thin plates during bending.
ScientificWorldJournal
PUBLISHED: 02-08-2014
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A novel numerical manifold method was derived from the cubic B-spline basis function. The new interpolation function is characterized by high-order coordination at the boundary of a manifold element. The linear elastic-dynamic equation used to solve the bending vibration of thin plates was derived according to the principle of minimum instantaneous potential energy. The method for the initialization of the dynamic equation and its solution process were provided. Moreover, the analysis showed that the calculated stiffness matrix exhibited favorable performance. Numerical results showed that the generalized degrees of freedom were significantly fewer and that the calculation accuracy was higher for the manifold method than for the conventional finite element method.
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Identification of boron-deficiency-responsive microRNAs in Citrus sinensis roots by Illumina sequencing.
BMC Plant Biol.
PUBLISHED: 01-16-2014
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Boron (B)-deficiency is a widespread problem in many crops, including Citrus. MicroRNAs (miRNAs) play important roles in nutrient deficiencies. However, little is known on B-deficiency-responsive miRNAs in plants. In this study, we first identified miRNAs and their expression pattern in B-deficient Citrus sinensis roots by Illumina sequencing in order to identify miRNAs that might be involved in the tolerance of plants to B-deficiency.
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CD73 expression in RPE cells is associated with the suppression of conventional CD4 cell proliferation.
Exp. Eye Res.
PUBLISHED: 01-09-2014
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CD73 is intensively involved in the regulation of immune responses through the conversion of pro-inflammatory ATP to immunosuppressive adenosine. Herein, we clarified whether cells in the retina express CD73 and participate in the regulation of inflammatory eye diseases such as experimental autoimmune uveitis (EAU). First, immunofluorescence staining was performed to compare the distribution of CD73(+) cells in the retinas of EAU-induced and normal B10RIII mice. The results revealed that a layer of cells in the normal retina that was consistent with the location of retinal pigment epithelial (RPE) cells strongly expressing CD73, and the expression was markedly reduced in the presence of EAU. Thereafter, EAU was also induced in C57BL/6 mice by active immunization or adoptive transfer. CD73 expression in isolated RPE cells was assessed by real-time RT-PCR and western blotting, and the catalytic abilities of the cells to convert AMP to adenosine were determined using HPLC analyses. Compared to the normal control, significantly decreased CD73 expression and AMP catalytic ability were found in the RPE cells isolated from inflamed eyes. CD73 expression and activity were also studied in cultured RPE cells treated with different stimuli, such as Toll-like receptor ligands and cytokines. Highly varied functional CD73 expression was observed in RPE cells through cytokines or Toll-like receptor agonist treatments. Finally, whether RPE cells could regulate the immune response, particularly the proliferation of CD4 cells, through surface-expressed CD73 was determined using a two-chamber assay. The robust inhibition of conventional T-cell proliferation was uniquely observed when CD73(+) RPE cells in the upper chamber were in the presence of AMP. To further confirm the function of CD73 in RPE cells, Cd73(-/-) RPE cells were isolated, and CD73-rescued control cells were constructed. CD73(+)Cd73(-/-) RPE, not Cd73(-/-) RPE, significantly suppressed interacted CD4 cells proliferation and cytokine production. Taken together, these data suggest that naive RPE cells suppressed the immune response through their high expression of CD73. The expression of CD73 in RPE cells could be regulated through many factors, and down-regulated CD73 expression attenuated the suppressive effect of RPE on the proliferation of conventional CD4 cells.
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Carbon monoxide potently prevents ischemia-induced high-mobility group box 1 translocation and release and protects against lethal renal ischemia-reperfusion injury.
Kidney Int.
PUBLISHED: 01-09-2014
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High-mobility group box 1 (HMGB1) is a chromatin-binding nuclear molecule that has potent proinflammatory effects once released by damaged cells. In some disease models, carbon monoxide (CO) exhibits anti-inflammatory and protective properties. Here, we investigated whether the protective effect of CO on renal ischemia-reperfusion injury is associated with the inhibition of HMGB1 translocation and release. A renal ischemia-reperfusion injury model was established with a 100% mortality rate in untreated mice. Pretreatment with the CO-releasing molecule-2 (CORM-2) resulted in 100% survival, maximal preservation of renal function, a marked reduction in pathological damage, and blunted upregulation of TLR4, RAGE, TNF-?, IL-1?, IL-6, and MCP1 mRNA. Interestingly, CORM-2 pretreatment almost completely inhibited ischemia-induced HMGB1 nucleocytoplasmic shuttling and release. This inhibition was associated with a decrease in nuclear histone acetyltransferase activity. Indeed, CORM-2 pretreatment inhibited the acetylation and release of HMGB1 during hypoxic culture of primary mouse renal tubular epithelia cells in vitro. Using the same renal ischemia-reperfusion injury model, neutralization of HMGB1 was protective, and administration of exogenous HMGB1 largely reversed the protective effect of CORM-2 on kidney ischemia-reperfusion injury. Thus, CORM-2-delivered CO protects against lethal renal ischemia-reperfusion injury. This protection is correlated with the prevention of HMGB1 nuclear-cytoplasmic translocation and release.
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Vitreous and plasma VEGF levels as predictive factors in the progression of proliferative diabetic retinopathy after vitrectomy.
PLoS ONE
PUBLISHED: 01-01-2014
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To investigate the vitreous and plasma levels of vascular endothelial growth factor (VEGF) in patients with proliferative diabetic retinopathy (PDR) and to determine whether they predict a disease prognosis after primary vitrectomy.
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The complete mitochondrial genomes of six species of tetranychus provide insights into the phylogeny and evolution of spider mites.
PLoS ONE
PUBLISHED: 01-01-2014
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Many spider mites belonging to the genus Tetranychus are of agronomical importance. With limited morphological characters, Tetranychus mites are usually identified by a combination of morphological characteristics and molecular diagnostics. To clarify their molecular evolution and phylogeny, the mitochondrial genomes of the green and red forms of Tetranychus urticae as well as T. kanzawai, T. ludeni, T. malaysiensis, T. phaselus, T. pueraricola were sequenced and compared. The seven mitochondrial genomes are typical circular molecules of about 13,000 bp encoding and they are composed of the complete set of 37 genes that are usually found in metazoans. The order of the mitochondrial (mt) genes is the same as that in the mt genomes of Panonychus citri and P. ulmi, but very different from that in other Acari. The J-strands of the mitochondrial genomes have high (?84%) A+T contents, negative GC-skews and positive AT-skews. The nucleotide sequence of the cox1 gene, which is commonly used as a taxon barcode and molecular marker, is more highly conserved than the nucleotide sequences of other mitochondrial genes in these seven species. Most tRNA genes in the seven genomes lose the D-arm and/or the T-arm. The functions of these tRNAs need to be evaluated. The mitochondrial genome of T. malaysiensis differs from the other six genomes in having a slightly smaller genome size, a slight difference in codon usage, and a variable loop in place of the T-arm of some tRNAs by a variable loop. A phylogenic analysis shows that T. malaysiensis first split from other Tetranychus species and that the clade of the family Tetranychoidea occupies a basal position in the Trombidiformes. The mt genomes of the green and red forms of T. urticae have limited divergence and short evolutionary distance.
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Optimizing hill seeding density for high-yielding hybrid rice in a single rice cropping system in South china.
PLoS ONE
PUBLISHED: 01-01-2014
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Mechanical hill direct seeding of hybrid rice could be the way to solve the problems of high seeding rates and uneven plant establishment now faced in direct seeded rice; however, it is not clear what the optimum hill seeding density should be for high-yielding hybrid rice in the single-season rice production system. Experiments were conducted in 2010 and 2011 to determine the effects of hill seeding density (25 cm×15 cm, 25 cm×17 cm, 25 cm×19 cm, 25 cm×21 cm, and 25 cm×23 cm; three to five seeds per hill) on plant growth and grain yield of a hybrid variety, Nei2you6, in two fields with different fertility (soil fertility 1 and 2). In addition, in 2012 and 2013, comparisons among mechanical hill seeding, broadcasting, and transplanting were conducted with three hybrid varieties to evaluate the optimum seeding density. With increases in seeding spacing from 25 cm×15 cm to 25 cm×23 cm, productive tillers per hill increased by 34.2% and 50.0% in soil fertility 1 and 2. Panicles per m2 declined with increases in seeding spacing in soil fertility 1. In soil fertility 2, no difference in panicles per m2 was found at spacing ranging from 25 cm×17 cm to 25 cm×23 cm, while decreases in the area of the top three leaves and aboveground dry weight per shoot at flowering were observed. Grain yield was the maximum at 25 cm×17 cm spacing in both soil fertility fields. Our results suggest that a seeding density of 25 cm×17 cm was suitable for high-yielding hybrid rice. These results were verified through on-farm demonstration experiments, in which mechanical hill-seeded rice at this density had equal or higher grain yield than transplanted rice.
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Evolving molecular epidemiological profile of human immunodeficiency virus 1 in the southwest border of China.
PLoS ONE
PUBLISHED: 01-01-2014
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We have previously reported in Xishuangbanna (Banna) Dai Autonomous Prefecture, a well-developed tourist destination in the southwest border of China, that HIV-1 transmitted dominantly through heterosexual contact with less divergent genotypes and few drug resistant mutations. Due to the rapid increase of newly diagnosed HIV-1 cases per year in Banna in recent years, it's important to evaluate the evolution of HIV-1 molecular epidemiology for the better understanding of ongoing HIV-1 outbreak in this region.
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Mucosal SIV Vaccines Comprising Inactivated Virus Particles and Bacterial Adjuvants Induce CD8(+) T-Regulatory Cells that Suppress SIV-Positive CD4(+) T-Cell Activation and Prevent SIV Infection in the Macaque Model.
Front Immunol
PUBLISHED: 01-01-2014
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A new paradigm of mucosal vaccination against human immunodeficiency virus (HIV) infection has been investigated in the macaque model. A vaccine consisting of inactivated simian immunodeficiency virus (SIV)mac239 particles together with a living bacterial adjuvant (either the Calmette and Guerin bacillus, Lactobacillus plantarum or Lactobacillus rhamnosus) was administered to macaques via the vaginal or oral/intragastric route. In contrast to all established human and veterinary vaccines, these three vaccine regimens did not elicit SIV-specific antibodies nor cytotoxic T-lymphocytes but induced a previously unrecognized population of non-cytolytic MHCIb/E-restricted CD8(+) T-regulatory cells that suppressed the activation of SIV-positive CD4(+) T-lymphocytes. SIV reverse transcription was thereby blocked in inactivated CD4(+) T-cells; the initial burst of virus replication was prevented and the vaccinated macaques were protected from a challenge infection. For 3-14?months after intragastric immunization, 24 macaques were challenged intrarectally with a high dose of SIVmac239 or with the heterologous strain SIV B670 (both strains grown on macaques PBMC). Twenty-three of these animals were found to be protected for up to 48?months while all 24 control macaques became infected. This protective effect against SIV challenge together with the concomitant identification of a robust ex vivo correlate of protection suggests a new approach for developing an HIV vaccine in humans. The induction of this new class of CD8(+) T-regulatory cells could also possibly be used therapeutically for suppressing HIV replication in infected patients and this novel tolerogenic vaccine paradigm may have potential applications for treating a wide range of immune disorders and is likely to may have profound implications across immunology generally.
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Dimethyloxaloylglycine improves angiogenic activity of bone marrow stromal cells in the tissue-engineered bone.
Int. J. Biol. Sci.
PUBLISHED: 01-01-2014
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One of the big challenges in tissue engineering for treating large bone defects is to promote the angiogenesis of the tissue-engineered bone. Hypoxia inducible factor-1? (HIF-1?) plays an important role in angiogenesis-osteogenesis coupling during bone regeneration, and can activate a broad array of angiogenic factors. Dimethyloxaloylglycine (DMOG) can activate HIF-1? expression in cells at normal oxygen tension. In this study, we explored the effect of DMOG on the angiogenic activity of bone mesenchymal stem cells (BMSCs) in the tissue-engineered bone. The effect of different concentrations of DMOG on HIF-1a expression in BMSCs was detected with western blotting, and the mRNA expression and secretion of related angiogenic factors in DMOG-treated BMSCs were respectively analyzed using qRT-PCR and enzyme linked immunosorbent assay. The tissue-engineered bone constructed with ?-tricalcium phosphate (?-TCP) and DMOG-treated BMSCs were implanted into the critical-sized calvarial defects to test the effectiveness of DMOG in improving the angiogenic activity of BMSCs in the tissue-engineered bone. The results showed DMOG significantly enhanced the mRNA expression and secretion of related angiogenic factors in BMSCs by activating the expression of HIF-1?. More newly formed blood vessels were observed in the group treated with ?-TCP and DMOG-treated BMSCs than in other groups. And there were also more bone regeneration in the group treated with ?-TCP and DMOG-treated BMSCs. Therefore, we believed DMOG could enhance the angiogenic activity of BMSCs by activating the expression of HIF-1?, thereby improve the angiogenesis of the tissue-engineered bone and its bone healing capacity.
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A novel tumor targeting drug carrier for optical imaging and therapy.
Theranostics
PUBLISHED: 01-01-2014
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Human serum albumin (HSA), a naturally abundant protein in blood plasma and tissue fluids, has an extraordinary ligand-binding capacity and is advocated as a drug carrier to facilitate drug delivery. To render it tumor targeting specificity, we generated a recombinant HSA fused with the amino-terminal fragment (ATF) of urokinase, allowing the fusion protein to bind to urokinase receptor (uPAR), which is shown to have a high expression level in many tumors, but not in normal tissues. To test the efficacy of this bifunctional protein (ATF-HSA), a hydrophobic photosensitizer (mono-substituted ?-carboxy phthalocyanine zinc, CPZ) was chosen as a cytotoxic agent. A dilution-incubation-purification (DIP) strategy was developed to load the ATF-HSA with this CPZ, forming a 1:1 molecular complex (ATF-HSA:CPZ). We demonstrated that CPZ was indeed embedded inside ATF-HSA at the fatty acid binding site 1 (FA1) of HSA, giving a hydrodynamic radius of 7.5 nm, close to HSA's (6.5 nm). ATF-HSA:CPZ showed high stability and remarkable optical and photophysical properties in aqueous solution. In addition, the molecular complex ATF-HSA:CPZ can bind to recombinant uPAR in vitro and uPAR on tumor cell surfaces, and was efficient in photodynamic killing of tumor cells. The tumor-killing potency of this molecular complex was further demonstrated in a tumor-bearing mouse model at a dose of 0.080 ?mol / kg, or 0.050 mg CPZ / kg of mouse body weight. Using fluorescent molecular tomography (FMT), ATF-HSA:CPZ was shown to accumulate specifically in tumors, and importantly, such tumor retention was higher than that of HSA:CPZ. Together, these results indicate that ATF-HSA:CPZ is not only an efficient tumor-specific cytotoxic agent, but also an useful tumor-specific imaging probe. This bifunctional protein ATF-HSA can also be used as a drug carrier for other types of cytotoxic or imaging agents to render them specificity for uPAR-expressing tumors.
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Wnt5a through noncanonical Wnt/JNK or Wnt/PKC signaling contributes to the differentiation of mesenchymal stem cells into type II alveolar epithelial cells in vitro.
PLoS ONE
PUBLISHED: 01-01-2014
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The differentiation of mesenchymal stem cells (MSCs) into type II alveolar epithelial (AT II) cells is critical for reepithelization and recovery in acute respiratory distress syndrome (ARDS), and Wnt signaling was considered to be the underlying mechanisms. In our previous study, we found that canonical Wnt pathway promoted the differentiation of MSCs into AT II cells, however the role of the noncanonical Wnt pathway in this process is unclear. It was disclosed in this study that noncanonical Wnt signaling in mouse bone marrow-derived MSCs (mMSCs) was activated during the differentiation of mMSCs into AT II cells in a modified co-culture system with murine lung epithelial-12 cells and small airway growth media. The levels of surfactant protein (SP) C, SPB and SPD, the specific markers of AT II cells, increased in mMSCs when Wnt5a was added to activate noncanonical Wnt signaling, while pretreatment with JNK or PKC inhibitors reversed the promotion of Wnt5a. The differentiation rate of mMSCs also depends on their abilities to accumulate and survive in inflammatory tissue. We found that the Wnt5a supplement promoted the vertical and horizontal migration of mMSCs, ameliorated the cell death and the reduction of Bcl-2/Bax induced by H2O2. The effect of Wnt5a on the migration of mMSCs and their survival after H2O2 exposure were partially inhibited with PKC or JNK blockers. In conclusion, Wnt5a through Wnt/JNK signaling alone or both Wnt/JNK and Wnt/PKC signaling promoted the differentiation of mMSCs into AT II cells and the migration of mMSCs; through Wnt/PKC signaling, Wnt5a increased the survival of mMSCs after H2O2 exposure in vitro.
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Culex tarsalis vitellogenin gene promoters investigated in silico and in vivo using transgenic Drosophila melanogaster.
PLoS ONE
PUBLISHED: 01-01-2014
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Genetic modification, or transgenesis, is a powerful technique to investigate the molecular interactions between vector-borne pathogens and their arthropod hosts, as well as a potential novel approach for vector-borne disease control. Transgenesis requires the use of specific regulatory regions, or promoters, to drive expression of genes of interest in desired target tissues. In mosquitoes, the vast majority of described promoters are from Anopheles and Aedes mosquitoes.
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Correlated diffusion of colloidal particles near a liquid-liquid interface.
PLoS ONE
PUBLISHED: 01-01-2014
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Optical microscopy and multi-particle tracking are used to investigate the cross-correlated diffusion of quasi two-dimensional colloidal particles near an oil-water interface. The behaviors of the correlated diffusion along longitudinal and transverse direction are asymmetric. It is shown that the characteristic length for longitudinal and transverse correlated diffusion are particle diameter d and the distance z from particle center to the interface, respectively, for large particle separation z. The longitudinal and transverse correlated diffusion coefficient D||(r) and D[perpendicular](r) are independent of the colloidal area fraction n when n < 0.3, which indicates that the hydrodynamic interactions(HIs) among the particles are dominated by HIs through the surrounding fluid for small n. For high area fraction n > 0.4 the power law exponent for the spatial decay of [Formula: see text] begins to decrease, which suggests the HIs are more contributed from the 2D particle monolayer self for large n.
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Highly Enantioselective Copper-Catalyzed Propargylic Substitution of Propargylic Acetates with 1,3-Dicarbonyl Compounds.
Org. Lett.
PUBLISHED: 12-27-2013
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A chiral tridentate ketimine P,N,N-ligand has been successfully applied in the copper-catalyzed enantioselective propargylic substitution of propargylic acetates with a variety of ?-dicarbonyl compounds, in which excellent enantioselectivities (up to >99% ee) and high yields have been obtained.
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[Age estimation using content of sjTREC in human peripheral blood].
Fa Yi Xue Za Zhi
PUBLISHED: 12-20-2013
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To determine and verify the correlation formula of age estimation using the content of signal joint T-cell receptor excision DNA circle (sjTREC) in human peripheral blood and to discuss its application value in forensic biological practice.
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The D-ring, not the A-ring, Rotates in Synechococcus OS-B Phytochrome.
J. Biol. Chem.
PUBLISHED: 12-10-2013
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Phytochrome photoreceptors in plants and microorganisms switch photochromically between two states, controlling numerous important biological processes. Although this phototransformation is generally considered to involve rotation of ring D of the tetrapyrrole chromophore, Ulijasz et al. (2010, Nature 463, 250-254) proposed that the A-ring rotates instead. Here, we apply MAS NMR to the two parent states of following studies of the 23-kDa GAF-domain fragment of phytochrome from Synechococcus OS-B. Major changes occur at the A-ring covalent linkage to the protein as well as at the protein residue contact of ring D. Conserved contacts associated with the A-ring nitrogen rule out an A-ring photoflip, whereas loss of contact of the D-ring nitrogen to the protein implies movement of ring D. Although none of the methine bridges showed a chemical shift change comparable to those characteristic of the D-ring photoflip in canonical phytochromes, denaturation experiments showed conclusively that the same occurs in Synechococcus OS-B phytochrome upon photoconversion. The results are consistent with the D-ring being strongly tilted in both states and the C15=C16 double bond undergoing a Z/E isomerization upon light absorption. More subtle changes are associated with the A-ring linkage to the protein. Our findings thus disprove A-ring rotation and are discussed in relation to the position of the D-ring, photoisomerization and photochromicity in the phytochrome family.
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Effective Connectivity within Human Primary Visual Cortex Predicts Interindividual Diversity in Illusory Perception.
J. Neurosci.
PUBLISHED: 11-29-2013
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Visual perception depends strongly on spatial context. A classic example is the tilt illusion where the perceived orientation of a central stimulus differs from its physical orientation when surrounded by tilted spatial contexts. Here we show that such contextual modulation of orientation perception exhibits trait-like interindividual diversity that correlates with interindividual differences in effective connectivity within human primary visual cortex. We found that the degree to which spatial contexts induced illusory orientation perception, namely, the magnitude of the tilt illusion, varied across healthy human adults in a trait-like fashion independent of stimulus size or contrast. Parallel to contextual modulation of orientation perception, the presence of spatial contexts affected effective connectivity within human primary visual cortex between peripheral and foveal representations that responded to spatial context and central stimulus, respectively. Importantly, this effective connectivity from peripheral to foveal primary visual cortex correlated with interindividual differences in the magnitude of the tilt illusion. Moreover, this correlation with illusion perception was observed for effective connectivity under tilted contextual stimulation but not for that under iso-oriented contextual stimulation, suggesting that it reflected the impact of orientation-dependent intra-areal connections. Our findings revealed an interindividual correlation between intra-areal connectivity within primary visual cortex and contextual influence on orientation perception. This neurophysiological-perceptual link provides empirical evidence for theoretical proposals that intra-areal connections in early visual cortices are involved in contextual modulation of visual perception.
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Renoprotection of Danshen Injection on streptozotocin-induced diabetic rats, associated with tubular function and structure.
J Ethnopharmacol
PUBLISHED: 11-11-2013
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Danshen Injection, the aqueous extracts of Radix Salvia miltiorrhiza (S. miltiorrhiza), is one of the most commonly used traditional Chinese herbs in chronic renal failure treatment. In present study, the mechanism of the renoprotective effect of Danshen Injection was analyzed on streptozocin (STZ)-induced diabetic rats.
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Tumor-promoting and -suppressive roles of autophagy in the same mouse model of BrafV600E-driven lung cancer.
Cancer Discov
PUBLISHED: 11-09-2013
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Although a role of autophagy in cancer development and progression has received increasing appreciation in recent years, there are still significantly uncertain and conflicting results about its tumor-suppressive and -promoting functions, and, more importantly, a lack of understanding of mechanisms underlying these opposing activities. The work presented by Strohecker and colleagues uses an innovative approach to address these challenges by examining the effects of inactivating the key autophagy gene Atg7 at different stages of oncogenic development in a BrafV600E-driven mouse lung cancer model. The authors show that autophagy blockage initially accelerated tumor development, but suppressed tumor progression in later stages, converting adenomas to oncocytomas and increasing mouse survival. Importantly, they identify a critical role of glutamine dependency in the suppression of BrafV600E-induced cancer, thus revealing an important mechanism by which autophagy may promote tumor progression in different cellular contexts.
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One-step generation of engineered drug-laden poly(lactic-co-glycolic acid) micropatterned with Teflon chips for potential application in tendon restoration.
ACS Appl Mater Interfaces
PUBLISHED: 10-22-2013
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Regulating cellular behaviors such as cellular spatial arrangement and cellular phenotype is critical for managing tissue microstructure and biological function for engineered tissue regeneration. We herein pattern drug-laden poly(lactic-co-glycolic acid) (PLGA) into grooves using novel Teflon stamps (that possess excellent properties of resistance to harsh organic solvents and molecular adsorption) for engineered tendon-repair therapeutics. The drug release and biological properties of melatonin-laden PLGA grooved micropatterns are investigated. The results reveal that fibroblasts cultured on the melatonin-laden PLGA groove micropatterns not only display significant cell alignment that mimics the cell behavior in native tendon, but also promote the secretion of a major extracellular matrix in tendon, type I collagen, indicating great potential for the engineering of functional tendon regeneration.
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Enantioselective Copper-Catalyzed Decarboxylative Propargylic Alkylation of Propargyl ?-Ketoesters with a Chiral Ketimine P,N,N-Ligand.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 10-21-2013
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The first enantioselective copper-catalyzed decarboxylative propargylic alkylation has been developed. Treatment of propargyl ?-ketoesters with a catalyst, prepared in situ from [Cu(CH3 CN)4 BF4 ] and a newly developed chiral tridentate ketimine P,N,N-ligand under mild reaction conditions, generates ?-ethynyl ketones in good yields and with high enantioselectivities without requiring the pregeneration of ketone enolates. This new process provides facile access to a range of chiral ?-ethynyl ketones in a highly enantioenriched form.
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Antiviral treatment of hepatitis C virus infection and factors affecting efficacy.
World J. Gastroenterol.
PUBLISHED: 09-28-2013
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Hepatitis C virus (HCV) infection is the leading cause of chronic liver-related diseases, including cirrhosis, liver failure, and hepatocellular carcinoma. Currently, no effective vaccine is available for HCV infection. Polyethylene glycol interferon-? (PegIFN-?) in combination with ribavirin (RBV) is the standard of care (SOC) for chronic hepatitis C. However, the efficacy of PegIFN-? and RBV combination therapy is less than 50% for genotype 1 HCV, which is the dominant virus in humans. In addition, IFN and RBV have several severe side effects. Therefore, strategies to improve sustained virological response (SVR) rates have been an important focus for clinical physicians. The serine protease inhibitors telaprevir and boceprevir were approved by the United States Food and Drug Administration in 2011. The addition of HCV protease inhibitors to the SOC has significantly improved the efficacy of treatments for HCV infection. Several direct-acting antiviral drugs currently in late-stage clinical trials, both with and without peg-IFN and RBV, have several advantages over the previous SOC, including higher specificity and efficacy, fewer side effects, and the ability to be administered orally, and might be optimal regimens in the future. Factors affecting the efficacy of anti-HCV treatments based on IFN-? include the HCV genotype, baseline viral load, virological response during treatment, host IL28B gene polymorphisms and hepatic steatosis. However, determining the effect of the above factors on DAA therapy is necessary. In this review, we summarize the development of anti-HCV agents and assess the main factors affecting the efficacy of antiviral treatments.
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Overexpression of S100A9 in human glioma and in-vitro inhibition by aspirin.
Eur. J. Cancer Prev.
PUBLISHED: 09-26-2013
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Our previous work has shown that S100A9 promotes the growth of glioma cells. The aim of this study was to investigate S100A9 expression in glioma cells and to explore the potential of NSAIDs in the inhibition of S100A9. The levels of S100A9 were analyzed in five normal human brain tissues and 109 astrocytomas by immunohistochemical analysis. In addition, S100A9 levels were detected in normal human astrocytes, glioma cell lines, and six pairs of matched astrocytoma tissues by reverse transcription-PCR or western blotting analysis. After treatment with 4, 8, and 16 mmol/l aspirin, cell viability, early apoptosis rate, and S100A9 levels were quantified. Cell viability and the changes in S100A9 levels were also examined in glioma cells exposed to a cyclooxygenase-2 inhibitor, NS-398, alone and in combination with prostaglandin E2. We found that S100A9 was upregulated in astrocytomas and was significantly (P<0.05) correlated with histologic grades. S100A9 protein levels were also elevated in six astrocytomas compared with matched adjacent noncancerous tissues. Both S100A9 mRNA and protein levels were higher in glioma cell lines than in normal human astrocytes (P<0.05). Aspirin treatment inhibited cell proliferation and caused early apoptosis in glioma, coupled with reduced S100A9 levels. Treatment with NS-398 decreased cell growth and expression of S100A9 in glioma cells; these effects were partially reversed by exogenous prostaglandin E2. These results suggest overexpression of S100A9 in glioma cells. Aspirin may be a novel candidate for targeted prevention of S100A9 overexpression in glioma cells.
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Who funds their health savings account and why?
Int J Health Care Finance Econ
PUBLISHED: 08-30-2013
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Health savings account (HSA) enrollment has increased markedly in the last several years, but little is known about the factors affecting account funding decisions. We use a unique data set containing from a bank that exclusively services HSA funds linked to health status, benefit design, plan coverage, and enrollee characteristics from a very large national health insurance company to examine the factors associated with HSA contribution. We found that even small employer contributions had an apparently large effect on the decision to open an account: the account-opening rate was 50 % higher when employers contributed to the account. Conditional on opening an HSA, employee contributions were negatively associated with the amount of employer contribution, contributions rose with age, income, education, and health care need.
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A colorimetric and ratiometric fluorescent probe for sulfite based on an intramolecular cleavage mechanism.
Luminescence
PUBLISHED: 07-30-2013
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A colorimetric and ratiometric fluorescent sulfite probe, the levulinate of 4-hydroxynaphthalimide, was successfully synthesized from 4-hydroxy-naphthalimide and levulinic acid. Through sulfite-mediated intramolecular cleavage, the probe was converted into 4-hydroxynaphthalimide, which when excited at 450 nm, displayed a large Stokes shift due to the intramolecular charge transfer process. The probe exhibited high selectivity and sensitivity towards sulfite over other typical anionic species (F(-) , Cl(-) , Br(-) , I(-) , HPO4 (2-) , SO4 (2-) , NO3 (-) , AcO(-) , ClO4 (-) , HCO3 (-) ) in HEPES-buffered solution (25 mm, pH 7.4, 50% acetonitrile, v/v). Copyright © 2013 John Wiley & Sons, Ltd.
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[Observation on therapeutic effect of round-sharp needle of new nine-needle and elongated needle for piriformis syndrome with triple puncture method].
Zhongguo Zhen Jiu
PUBLISHED: 07-27-2013
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To compare the efficacy differences between round-sharp needle of new nine-needle and elongated needle for piriformis syndrome, and explore its action mechanism.
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Effects of granulation on organic acid metabolism and its relation to mineral elements in Citrus grandis juice sacs.
Food Chem
PUBLISHED: 07-24-2013
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We investigated the effects of granulation on organic acid metabolism and its relation to mineral elements in Guanximiyou pummelo (Citrus grandis) juice sacs. Granulated juice sacs had decreased concentrations of citrate and isocitrate, thus lowering juice sac acidity. By contrast, malate concentration was higher in granulated juice sacs than in normal ones. The reduction in citrate concentration might be caused by increased degradation, as indicated by enhanced aconitase activity, whilst the increase in malate concentration might be caused by increased biosynthesis, as indicated by enhanced phosphoenolpyruvate carboxylase (PEPC). Real time quantitative reverse transcription PCR (qRT-PCR) analysis showed that the activities of most acid-metabolizing enzymes were regulated at the transcriptional level, whilst post-translational modifications might influence the PEPC activity. Granulation led to increased accumulation of mineral elements (especially phosphorus, magnesium, sulphur, zinc and copper) in juice sacs, which might be involved in the incidence of granulation in pummelo fruits.
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Defect-induced loss mechanisms in polymer-inorganic planar heterojunction solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 07-23-2013
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The effect of ZnO defects on photoexcited charge carrier recombination and forward induced charge transfer was studied in organic-inorganic bilayer organic heterojunction solar cells. Decreased bimolecular recombination via passivation of ZnO nanopariticle defects resulted in longer carrier lifetime as determined by transient photovoltage (TPV) measurements. It was also found by time-resolved photoluminescence (TRPL) measurements that defect passivation decreased the fluorescence lifetime which indicated higher exciton dissociation efficiency. Through passivation of the ZnO nanoparticles defects, the two loss mechanisms were reduced and the power conversion efficiency (PCE) is significantly enhanced.
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Precise organization of metal nanoparticles on DNA origami template.
Methods
PUBLISHED: 07-18-2013
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Nanoscale assemblies of metal nanoparticles in one dimension (1D) to three dimensions (3D) can exhibit novel phenomena that are not observed in the amorphous state. Bottom-up assembly technique is expected to overcome the resolution limit of top-down method and casts a new light on the nanofabrication field. DNA origami, which is mainly used to construct discrete and addressable nanostructures, can be utilized to assemble functional colloidal nanoparticles into delicate geometries with interesting properties. This review aims to summarize the methods that use DNA origami structures as templates to precisely organize metal nanoparticles, such as gold nanospheres (AuNSs) gold nanorods (AuNRs) and silver nanoparticles (AgNPs). The potential applications and the perspective are also discussed.
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Distinct FAK activities determine progenitor and mammary stem cell characteristics.
Cancer Res.
PUBLISHED: 07-05-2013
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Mammary stem cells (MaSC) and progenitor cells are important for mammary gland development and maintenance and may give rise to mammary cancer stem cells (MaCSC). Yet, there remains limited understanding of how these cells contribute to tumorigenesis. Here, we show that conditional deletion of focal adhesion kinase (FAK) in embryonic mammary epithelial cells (MaEC) decreases luminal progenitors and basal MaSCs, reducing their colony-forming and regenerative potentials in a cell-autonomous manner. Loss of FAK kinase activity in MaECs specifically impaired luminal progenitor proliferation and alveologenesis, whereas a kinase-independent activity of FAK supported ductal invasion and basal MaSC activity. Deficiency in luminal progenitors suppressed tumorigenesis and MaCSC formation in a mouse model of breast cancer. In contrast with the general inhibitory effect of FAK attenuation, inhibitors of FAK kinase preferentially inhibited proliferation and tumorsphere formation of luminal progenitor-like, but not MaSC-like, human breast cancer cells. Our findings establish distinct kinase-dependent and -independent activities of FAK that differentially regulate luminal progenitors and basal MaSCs. We suggest that targeting these distinct functions may tailor therapeutic strategies to address breast cancer heterogeneity more effectively.
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Leaf cDNA-AFLP analysis of two citrus species differing in manganese tolerance in response to long-term manganese-toxicity.
BMC Genomics
PUBLISHED: 07-01-2013
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Very little is known about manganese (Mn)-toxicity-responsive genes in citrus plants. Seedlings of Xuegan (Citrus sinensis) and Sour pummelo (Citrus grandis) were irrigated for 17 weeks with nutrient solution containing 2 ?M (control) or 600 ?M (Mn-toxicity) MnSO?. The objectives of this study were to understand the mechanisms of citrus Mn-tolerance and to identify differentially expressed genes, which might be involved in Mn-tolerance.
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Variability in visual cortex size reflects tradeoff between local orientation sensitivity and global orientation modulation.
Nat Commun
PUBLISHED: 06-27-2013
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The surface area of early visual cortices varies several fold across healthy adult humans and is genetically heritable. But the functional consequences of this anatomical variability are still largely unexplored. Here we show that interindividual variability in human visual cortical surface area reflects a tradeoff between sensitivity to visual details and susceptibility to visual context. Specifically, individuals with larger primary visual cortices can discriminate finer orientation differences, whereas individuals with smaller primary visual cortices experience stronger perceptual modulation by global orientation contexts. This anatomically correlated tradeoff between discrimination sensitivity and contextual modulation of orientation perception, however, does not generalize to contrast perception or luminance perception. Neural field simulations based on a scaling of intracortical circuits reproduce our empirical observations. Together our findings reveal a feature-specific shift in the scope of visual perception from context-oriented to detail-oriented with increased visual cortical surface area.
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The complete mitochondrial genomes of two rice planthoppers, Nilaparvata lugens and Laodelphax striatellus: conserved genome rearrangement in Delphacidae and discovery of new characteristics of atp8 and tRNA genes.
BMC Genomics
PUBLISHED: 06-19-2013
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Nilaparvata lugens (the brown planthopper, BPH) and Laodelphax striatellus (the small brown planthopper, SBPH) are two of the most important pests of rice. Up to now, there was only one mitochondrial genome of rice planthopper has been sequenced and very few dependable information of mitochondria could be used for research on population genetics, phylogeographics and phylogenetic evolution of these pests. To get more valuable information from the mitochondria, we sequenced the complete mitochondrial genomes of BPH and SBPH. These two planthoppers were infected with two different functional Wolbachia (intracellular endosymbiont) strains (wLug and wStri). Since both mitochondria and Wolbachia are transmitted by cytoplasmic inheritance and it was difficult to separate them when purified the Wolbachia particles, concomitantly sequencing the genome of Wolbachia using next generation sequencing method, we also got nearly complete mitochondrial genome sequences of these two rice planthoppers. After gap closing, we present high quality and reliable complete mitochondrial genomes of these two planthoppers.
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[The relationship between centric relation-maximum intercuspation disharmony and temporomandibular dysfunction in class II patients].
Sichuan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 06-11-2013
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To investigate the relationship between the degree of displacement of centric relation-maximum intercuspation (CR-MI) and temporomandibular dysfunction (TMD) in Class II patients.
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[In vitro differentiation of synovial-derived mesenchymal stem cells infected by adenovirus vector mediated by bone morphogenetic protein 2/7 genes into fibrocartilage cells in rabbits].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 05-16-2013
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To investigate the feasibility of rabbit synovial-derived mesenchymal stem cells (SMSCs) differentiating into fibrocartilage cells by the recombinant adenovirus vector mediated by bone morphogenetic protein 2/7 (BMP-2/7) genes in vitro.
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Relationship between insulin resistance, dyslipidaemia and positive symptom in Chinese antipsychotic-naive first-episode patients with schizophrenia.
Psychiatry Res
PUBLISHED: 05-14-2013
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Controversial results concerning insulin resistance and lipid metabolism have been reported in antipsychotic-naive first-episode psychosis (AN-FEP) patients with schizophrenia of different countries. We aimed at determining whether schizophrenia-related psychopathology was associated with insulin resistance and/or dyslipidaemia in Chinese patients with AN-FEP schizophrenia. A cross-sectional study was performed in Chinese patients newly diagnosed with schizophrenia (n = 49, antipsychotic-naïve or antipsychotic medications< 2 weeks) and healthy volunteers (n = 30). The serum levels of insulin and triglyceride levels as well as homeostasis model of assessment-insulin resistance (HOMA-IR) index were significantly increased in AN-FEP patients, when compared with healthy volunteers. The gender difference had a significant impact on the insulin resistance and dyslipidaemia in these AN-FEP subjects. Multiple linear regression analysis demonstrated that the severity of positive symptoms of schizophrenia was negatively related to insulin resistance. No difference of serum glucose level, total cholesterol content, body mass index (BMI) and smoking status was detected between patients with schizophrenia and healthy controls. In conclusion, Chinese AN-FEP patients were more prone to insulin resistance and dyslipidaemia as compared to the healthy population, which is negatively correlated to positive symptoms. The results may contribute to the understanding of the relationship between the glucose/lipidaemia metabolic dysfunction and the psychopathology in patients with schizophrenia.
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Synthesis and electrochemical properties of Sb2Se3 nanowires prepared by a gas induced reduction method.
J Nanosci Nanotechnol
PUBLISHED: 05-08-2013
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Sb2Se3 nanowires have been prepared by a novel gas induced reduction (GIR) method. The precursor solution prepared by dissolving Sb2(OCH2CH2O)3 and SeO2 in a certain solvent was initially separated from the reductant, hydrazine hydrate. The reductant evaporated during the heating process, dissolved into the precursor solution and reacted with Sb3+ and SeO2 and finally Sb2Se3 nanostructures formed. Different solvents including diethanolamine, glycerol, ethylene glycol, deionized water, absolute ethanol and isopropyl alcohol were respectively used for comparison. It was found that when ethylene glycol was used as a solvent, pure, relatively homogeneous, and high aspect-ratio Sb2Se3 nanowires (40-120 nm in diameter and -100 microm in length) were prepared. Growth mechanism of the Sb2Se3 nanowires was proposed. The electrochemistry character of the nanowires was investigated via assembling into lithium ion batteries. The discharge capacity of Sb2Se3/Li cell cycled between 0.3 and 2.5 V was performed in the range of 142-1036 mA x h x g(-1) during the first 30 cycles, with the charge/discharge efficiency increasing from 89.4% to 97.5%.
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De novo hepatitis B virus infection from anti-HBc-positive donors in pediatric living donor liver transplantation.
J Dig Dis
PUBLISHED: 05-04-2013
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The aim of this study was to analyze the incidence and risk factors of de novo hepatitis B virus (HBV) infection from hepatitis B core antibody (anti-HBc)-positive donors in pediatric living donor liver transplantation (LDLT).
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Silicon Quantum Dots for Biological Applications.
Adv Healthc Mater
PUBLISHED: 04-30-2013
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Semiconductor nanoparticles (or quantum dots, QDs) exhibit unique optical and electronic properties such as size-controlled fluorescence, high quantum yields, and stability against photobleaching. These properties allow QDs to be used as optical labels for multiplexed imaging and in drug delivery detection systems. Luminescent silicon QDs and surface-modified silicon QDs have also been developed as potential minimally toxic fluorescent probes for bioapplications. Silicon, a well-known power electronic semiconductor material, is considered an extremely biocompatible material, in particular with respect to blood. This review article summarizes existing knowledge related to and recent research progress made in the methods for synthesizing silicon QDs, as well as their optical properties and surface-modification processes. In addition, drug delivery systems and in vitro and in vivo imaging applications that use silicon QDs are also discussed.
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Activation of canonical wnt pathway promotes differentiation of mouse bone marrow-derived MSCs into type II alveolar epithelial cells, confers resistance to oxidative stress, and promotes their migration to injured lung tissue in vitro.
J. Cell. Physiol.
PUBLISHED: 04-20-2013
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The differentiation of mesenchymal stem cells (MSCs) into type II alveolar epithelial (AT II) cells in vivo and in vitro, is critical for reepithelization and recovery in acute lung injury (ALI), but the mechanisms responsible for differentiation are unclear. In the present study, we investigated the role of the canonical wnt pathway in the differentiation of mouse bone marrow-derived MSCs (mMSCs) into AT II cells. Using a modified co-culture system with murine lung epithelial-12 (MLE-12) cells and small airway growth media (SAGM) to efficiently drive mMSCs differentiation, we found that GSK 3? and ?-catenin in the canonical wnt pathway were up-regulated during differentiation. The levels of surfactant protein (SP) C, SPB, and SPD, the specific markers of AT II cells, correspondingly increased in mMSCs when Wnt3a or LiCl was added to the co-culture system to activate wnt/?-catenin signaling. The expression of these factors was depressed to some extent by inhibiting the pathway with the addition of DKK 1. The differentiation rate of mMSCs also depends on their abilities to accumulate and survive in inflammatory tissue. Our results suggested that the activation of wnt/?-catenin signaling promoted mMSCs migration towards ALI mouse-derived lung tissue in a Transwell assay, and ameliorated the cell death and the reduction of Bcl-2/Bax induced by H(2) O(2), which simultaneously caused reduced GSK 3? and ?-catenin in mMSCs. These data supports a potential mechanism for the differentiation of mMSCs into AT II cells involving canonical wnt pathway activation, which may be significant to their application in ALI.
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Subretinal transfection of chitosan-loaded TLR3-siRNA for the treatment of experimental autoimmune uveitis.
Eur J Pharm Biopharm
PUBLISHED: 04-11-2013
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The local interaction between retinal pigment epithelium (RPE) and immigrated effector T cells is crucial for the pathogenesis of autoimmune uveitis. After being activated by the pattern recognition receptors (PRRs) signaling pathway, RPE can present the antigen reactivated invading autoreactive T cells, resulting in uveitis. In the present study, we showed that the transfection of chitosan-loaded TLR3-siRNA toward RPE could effectively remit experimental autoimmune uveitis (EAU) in B10RIII mice. Initially, we verified the constitutive expression of Tlr3 in RPE at high levels, which was not altered in response to TNF?, IFN? and IL-17A treatments. Compared with other TLRs, the activation of TLR3 signaling following polyIC treatment resulted in increased IL-6 and IFN? secretion from and MHCII expression on RPE. It is polyIC-, but not other TLR ligands, treated RPE showed significant synergetic effect with IL-17 on stimulating RPE secreting CXCL8 and CCl2, which might be resulted from elevated Il17ra expression in RPE following polyIC treatment. Furthermore, polyIC-treated RPE caused a robust stimulation of differentiation of CD4 cell toward Th1 or Th17 cells, in addition to the secretion of the cytokines IFN? and IL-17. The in vitro knockdown of TLR3 expression in RPE by chitosan/TLR3-siRNA transfection could effectively block polyIC-induced MHCII expression, pro-inflammatory cytokine secretion and autoreactive CD4 cell activation. Studies conducted in firefly luciferase gene transgenic mice demonstrated that the subretinal CS/Luci-siRNA transfection specifically reduced the luciferase activity in RPE but not in the liver and spleen. Finally, the CS/TLR3-siRNA was locally administered in the EAU induced B10RIII mice. The results revealed that chitosan-mediated TLR3-siRNA transfection had a significant therapeutic effect on either delaying the outbreak or remitting the severity of uveitis.
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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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Exendin-4 ameliorates oxidized-LDL-induced inhibition of macrophage migration in vitro via the NF-?B pathway.
Acta Pharmacol. Sin.
PUBLISHED: 04-08-2013
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Aim:To investigate the effects of the glucagon-like peptide-1 (GLP-1) receptor agonist exendin-4 on oxidized low-density lipoprotein (ox-LDL)-induced inhibition of macrophage migration and the mechanisms underlying the effects of exendin-4.Methods:Primary peritoneal macrophages were extracted from the peritoneal cavity of mice treated with 3% thioglycollate (2 mL, ip). Migration of the macrophages was examined using a cell migration assay. Macrophage migration-related factors including leptin-like ox-LDL receptor (LOX-1), cyclooxygenase 2 (COX-2), tumor necrosis factor (TNF)-?, interleukin-1 (IL-1)?, matrix metalloproteinase-2 (MMP-2), intercellular adhesion molecule (ICAM)-1 and macrophage migration inhibitory factor (MIF) were measured using semi-quantitative RT-PCR. Expression of MIF and ICAM-1 proteins was examined with ELISA. Gelatin zymography was used to evaluate the activity of MMP-9. Activation of the NF-?B pathway was determined by confocal laser scanning microscopy.Results:Treatment of the macrophages with ox-LDL (50 ?g/mL) markedly suppressed the macrophage migration. Furthermore, ox-LDL treatment substantially increased the expression of the macrophage migration-related factors, the activity of MMP-9 and the translocation of the NF-?B p65 subunit. These effects of ox-LDL were significantly ameliorated by pretreatment with the specific NF-?B inhibitor ammonium pyrrolidine dithiocarbamate (100 ?mol/L). These effects of ox-LDL were also significantly ameliorated by pretreatment with exendin-4 (25 and 50 nmol/L).Conclusion:Exendin-4 ameliorates the inhibition of ox-LDL on macrophage migration in vitro, via suppressing ox-LDL-induced expression of ICAM-1 and MIF, which is probably mediated by the NF-?B pathway.
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