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Find video protocols related to scientific articles indexed in Pubmed.
Color switchable, emission enhanced fluorescence realized by engineering C-dot@C-dot nanoparticles.
ACS Appl Mater Interfaces
PUBLISHED: 11-20-2014
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This paper reports the preparation and properties of color-switchable fluorescent carbon nanodots (C-dots). C-dots that emit dark turquoise and green-yellow fluorescence under 365 nm UV illumination were obtained from the hydrothermal decomposition of citric acid. Dark green fluorescent C-dots were obtained by conjugating prepared C-dots to form C-dot@C-dot nanoparticles. After successful conjugation of the C-dots, the fluorescence emission undergoes a blue shift of nearly 20 nm (?0.15 eV) under UV excitation at 370 nm. The C-dots emit golden rod, green-yellow, and gold light under excitation at 455 nm, which shows that the prepared C-dots are color-switchable. Furthermore, conjugation of the C-dots results in enhanced, red-shifted absorption of the ?-?* transition of the aromatic sp2 domains due to the conjugated ?-electron system. N incorporation in the carbon structure leads to a degree of dipoles for all the aromatic sp2 bonds. The enhanced absorption in a wide range from 226 to 601 nm indicates extended conjugation in the C-dot@C-dot structure. The time-resolved average lifetimes for the three different types of C-dots prepared in this study are 7.10, 7.65, and 4.07 ns. The radiative rate (reduced decay lifetime) increases when the C-dots are conjugated in the C-dot@C-dot nanoparticles, leading to the enhanced fluorescence emission. The fluorescence emission of the C-dot@C-dot nanoparticles can be used in applications such as flow cytometry and cell imaging.
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5.2-W high-repetition-rate eye-safe laser at 1525 nm generated by Nd:YVO4-YVO4 stimulated Raman conversion.
Opt Express
PUBLISHED: 11-18-2014
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We report herein an efficient eye-safe Raman laser, which is based upon Nd:YVO4-YVO4 and in-band pumped by a wavelength-locked laser diode array at 878.6 nm. By virtue of mitigated thermal load and improved pump absorption, a maximum average output power of 5.2 W at 1525 nm is obtained under the incident pump power of 30.6 W with the pulse repetition frequency of 140 kHz, corresponding to an optical efficiency of 17.0%.
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RNAi Knockdown of Hypoxia-Inducible Factor-1? Decreased the Proliferation, Migration, and Invasion of Hypoxic Hepatocellular Carcinoma Cells.
Cell Biochem. Biophys.
PUBLISHED: 11-13-2014
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The obstruction of hepatic arterial blood flow results in tumor tissue hypoxia and elevated expression of hypoxia-inducible factor-1alpha (HIF-1?). Our study evaluated whether lentivirus-mediated short interference RNA against HIF-1? inhibits proliferation, invasion, and migration of hepatocellular carcinoma (HCC) cells under hypoxia. RNA interference knockdown of HIF-1? was achieved by HIF-1?-directed lentiviral shRNA, in a rat HCC cell line cultured under hypoxia condition for varying length of times. The expression levels of HIF-1? and vascular endothelial growth factor were examined using reverse transcription polymerase chain reaction and western blot analyses. Cell proliferation, migration, and invasion were measured by cell viability, transwell migration, and invasion assays, respectively. Inhibition of HIF-1? expression by shRNA suppressed vascular endothelial growth factor mRNA and protein levels under both normoxia and hypoxia. It also suppressed cell migration and invasion, which were enhanced under hypoxic conditions. RNAi knockdown of HIF-1? further suppressed hypoxia-mediated inhibition of the cell proliferation. These data suggest that shRNA of HIF-1? could antagonize the hypoxia-mediated increase in hepatic cancer cell migration and invasion, and synergize with hypoxia to inhibit the cell proliferation in HCC cells.
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An acidic pectin lyase from Aspergillus niger with favorable efficiency in fruit juice clarification.
Lett. Appl. Microbiol.
PUBLISHED: 11-11-2014
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The pectin lyase gene pnl-zj5a from Aspergillus niger ZJ5 was identified and expressed in Pichia pastoris. PNL-ZJ5A was purified by ultrafiltration, anion exchange, and gel chromatography. The Km and Vmax values determined using citrus pectin were 0.66 mg ml(-1) and 32.6 ?mol·min(-1) ·mg(-1) , respectively. PNL-ZJ5A exhibited optimal activity at 43°C and retained activity over 25-50°C. PNL-ZJ5A was optimally active at pH 5 and effective in apple juice clarification. Compared with controls, PNL-ZJ5A increased the fruit juice yield significantly. Furthermore, PNL-ZJ5A reduced the viscosity of apple juice by 38.8% and increased its transmittance by 86.3%. PNL-ZJ5A combined with a commercial pectin esterase resulted in higher juice volume. This article is protected by copyright. All rights reserved.
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The progress in adjuvant therapy after curative resection of liver metastasis from colorectal cancer.
Drug Discov Ther
PUBLISHED: 11-11-2014
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Colorectal cancer liver metastases (CRLM) are common and found in almost 50% of patients with colorectal cancer. Surgical resection has proved to be the most effective therapy for metastatic colorectal cancer isolated to the liver and has yielded long term survival. However, recurrence frequently occurs within the remaining liver as well as at extra-hepatic sites. The role of adjuvant therapy has been investigated in many studies but has still been controversial until now. This review examines the incorporation of adjuvant systemic chemotherapy, regional chemotherapy with hepatic arterial infusion and molecular targeted therapy following liver resection for patients with CRLM, and summarized the advantage and adverse effects for these treatments. Finally, we propose the prospective of future adjuvant treatments to further improve prognosis.
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Use of a mini-instrument in endoscopic thyroidectomy via a breast approach to improve cosmetic outcomes.
Biosci Trends
PUBLISHED: 11-11-2014
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The objective of this research was to evaluate the clinical benefits of using a mini-instrument during endoscopic thyroidectomy via a breast approach (ETBA). Surgery-related indices and cosmetic results were compared for 20 patients underwent ETBA with a mini-instrument (ETBA-m) and 20 patients who underwent standard ETBA (sETBA). Patients were closely matched in terms of age, gender, tumor size, and pathology. Patients who underwent sETBA had a significantly larger area of dissection and total length of incisions compared to patients who underwent ETBA-m (136.25 ± 19.22 cm(2)vs. 105.25 ± 9.54 cm(2), p < 0.001 and 2.66 ± 0.09 cm vs. 2.08 ± 0.24 cm, p < 0.001). All patients who underwent ETBA-m commented that they preferred their current cosmetic appearance after they were shown a picture of the scars of a patient who underwent sETBA. Results of this study revealed that use of a mini-instrument in ETBA is technically safe and feasible and it offers improved cosmetic outcomes compared to sETBA.
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Enabling the 'host jump': structural determinants of receptor-binding specificity in influenza A viruses.
Nat. Rev. Microbiol.
PUBLISHED: 11-10-2014
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The recent emergence of the H7N9 avian influenza A virus and its ability to infect humans emphasize the epidemic and pandemic potential of these viruses. Interspecies transmission is the result of many factors, which ultimately lead to a change in the host tropism of the virus. One of the key factors involved is a shift in the receptor-binding specificity of the virus, which is mostly determined by mutations in the viral haemagglutinin (HA). In this Review, we discuss recent crystallographic studies that provide molecular insights into HA-host receptor interactions that have enabled several influenza A virus subtypes to 'jump' from avian to human hosts.
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Palladium-Catalyzed Aromatic C-H Bond Nitration Using Removable Directing Groups: Regiospecific Synthesis of Substituted o-Nitrophenols from Related Phenols.
J. Org. Chem.
PUBLISHED: 11-08-2014
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A general and regiospecific transformation of substituted phenols into the related o-nitrophenols has been achieved via a three-step process involving the palladium-catalyzed chelation-assisted ortho-C-H bond nitration as the key step. In the process, 2-pyridinyloxy groups act as removable directing groups for the palladium-catalyzed ortho-nitration of substituted 2-phenoxypridines, and they can be readily removed in the subsequent conversion of the resulting 2-(2-nitrophenoxy)pyridines into 2-nitrophenols.
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Comparative analysis of subtyping methods against a whole genome sequencing standard in Salmonella enterica serotype Enteritidis.
J. Clin. Microbiol.
PUBLISHED: 11-08-2014
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A retrospective investigation was performed to evaluate whole genome sequencing as a benchmark for comparing molecular subtyping methods for Salmonella enterica serotype Enteritidis (SE) and survey the population structure of commonly encountered SE outbreak isolates in the United States. A total of 52 SE isolates representing 16 major outbreaks and three sporadic cases between 2001 and 2012 were sequenced and subjected to subtyping by four different methods: 1) whole genome single nucleotide polymorphism typing (WGST), 2) multiple loci VNTR (variable-number tandem repeat) analysis (MLVA), 3) clustered regularly interspaced short palindromic repeats combined with multi-virulence-locus sequence typing (CRISPR-MVLST) and 4) pulsed-field gel electrophoresis (PFGE). WGST resolved all outbreak clusters and provided useful robust phylogenetic inference with high epidemiological correlation. While both MLVA and CRISPR-MVLST yielded higher discriminatory power than PFGE, MLVA outperformed in delineating outbreak clusters whereas CRISPR-MVLST showed the potential to trace major lineages and ecological origins of SE. Our results suggested that whole genome sequencing makes a viable platform for the evaluation and benchmarking molecular subtyping methods.
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[Comparison between annexin V-FITC/PI and Hoechst33342/PI double stainings in the detection of apoptosis by flow cytometry].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 11-07-2014
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Objective To evaluate the merits and demerits of annexin V-FITC/PI and Hoechst33342/PI double stainings in the detection of apoptosis by flow cytometry. Methods Hoechst33342/PI and annexin V-FITC/PI double stainings were performed to detect the apoptosis of thymocytes induced by DEX and K562 cells induced by H2O2. Results The anenxin V-FITC/PI double staining was able to detect the cell apoptosis in both DEX-induced thymocytes and H2O2-induced K562 cells as predicted, and the cell plotting was consistent with the principle of the method. Hoechest33342/PI double staining was able to detect cell apoptosis in the DEX-induced thymocytes, but this method showed a contradictory result in the early stage of H2O2-induced K562 cell apoptosis, and the cell plotting was in conflict with the principle of the method. Conclusion Compared with annexin V-FITC/PI double staining, the method of Hoechst33342/PI double staining in the detection of apoptosis by flow cytometry has some limitations.
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Protective effects of resveratrol on postmenopausal osteoporosis: regulation of SIRT1-NF-?B signaling pathway.
Acta Biochim. Biophys. Sin. (Shanghai)
PUBLISHED: 11-06-2014
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Postmenopausal osteoporosis severely jeopardizes human health. Seeking for therapeutic drugs without side effects is of great necessity. Our study was designed to investigate whether resveratrol, an agonist of SIRT1, could have favorable effect on osteoporosis and to explore the underlying mechanisms. Rat osteoporosis model (ovariectomy group, OVX) was established by bilateral ovariectomy. Three different doses of resveratrol were used: 5 mg/kg/d (low-dosed, RES(LD)), 25 mg/kg/d (medium-dosed, RES(MD)), and 45 mg/kg/d (high-dosed, RES(HD)). Results showed that RES(LD) did not show any significant effect on OVX alterations, while RES(MD) and RES(HD) significantly elevated the decreased bone mineral density induced by osteoporosis (RES(MD) 0.205±0.023, RES(HD) 0.214 ± 0.053 vs. OVX 0.165 ± 0.050, g/cm(2) respectively; P < 0.05). Serum markers alkaline phosphatase (ALP) and osteocalcin were moderately restored by resveratrol. Moreover, resveratrol improved bone structure in OVX rats, demonstrated by hematoxylin-eosin staining and micro-computed tomographic results. In vitro results revealed that resveratrol promoted osteoblast differentiation of bone marrow mesenchymal stromal cells, evidenced by the increase of ALP generation and mRNA expression of collagen 1 (P < 0.05; RES(MD), RES(HD) vs. control group). SIRT1 gene silencing by siRNA transfection blocked these beneficial effects of resveratrol (P < 0.05; RES+ SIRT1(KD) vs. RES(HD)). Western blot results showed that resveratrol activated SIRT1 and subsequently suppressed the activity of NF-?B with decreased expression level of p-I?B? and NF-?B p65 (P < 0.05). Our findings verified the effects of specific dosed resveratrol on postmenopausal osteoporosis through osteoblast differentiation via SIRT1-NF-?B signaling pathway. This study suggested the therapeutic potential of resveratrol against osteoporosis and stressed the importance of effective doses.
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[Effect of cerebral X-ray irradiation on learning and memory function in young SD rats].
Zhejiang Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 11-06-2014
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To investigate the effect of cerebral X-ray irradiation on learning and memory function in young rats. METHODS?Fifty-four SD rats aged 35 d were randomly divided into 3 groups with 18 in each group: rats in 3-d group and 7-d group received X-ray irradiation with a dose of 28.5 mGy/d for 3 d and 7 d?respectively; rats in control group received sham X-ray irradiation. Morris water maze (MWM) was tested when animals at age of 60 d; then the animals were sacrificed and brain samples were taken. The neurodegeneration was observed by Fluro-Jade B staining; the expression of N-methyl-aspartate (NMDA) receptors subunit 2B (NR2B) and postsynaptic density protein-95 (PSD-95) in the hippocampus were analyzed by immunofluorescence and Western blot methods?respectively?and ultrastructure of CA1 region was observed with electron microscopy. RESULTS? No significant difference in 1-4 d escape latency as shown in MWM test was noted between 3d group and control group (P>0.05); while the escape latency in 7d group was significantly longer than that in control group (P<0.01). No significant differences in lingering in the quadrant and the frequency of passing through the original platform between 3-d group and control group (P>0.05)?while those in 7-d group were significantly lower than those in control group (P<0.01). Compared to control group?the number of FJB positive cells in 7-d group was increased (P<0.01); the expressions of NR2B and PSD-95 in hippocampus CA1 region were also increased (P<0.05). The ultrastructure observation in 7-d group showed that the synapse structure of some neurons was impaired. CONCLUSION? X-ray irradiation may affect learning and memory function of young rats?which is associated with overexpression of NR2B and PSD-95 in hippocampal regions?
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Active vitamin D deficiency results in male infertility in young mice mediated by extracellular calcium and phosphorus.
Am. J. Physiol. Endocrinol. Metab.
PUBLISHED: 11-06-2014
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We used mice with targeted deletion of 25-hydroxyvitamin D 1?-hydroxylase [1?(OH)ase(-/-)] to investigate whether 1,25(OH)2D3-deficiency results in male infertility mediated by 1,25(OH)2D3 or extracellular calcium and phosphorus. Male 1?(OH)ase-/- and their wild-type littermates, fed either a normal diet or a rescue diet from weaning, were mated, at 6- to 14-weeks of age, with female wild-type mice on the same diet. The fertility efficiency of females was analyzed and the reproductive phenotypes of males were evaluated by histopathological and molecular techniques. Hypocalcemic and hypophosphatemic male 1?(OH)ase(-/-) mice on a normal diet developed infertility characterized by hypergonadotropic hypogonadism, with down-regulation of testicular calcium channels, lower intracellular calcium levels?decreased sperm count and motility, and histological abnormalities of the testes. The proliferation of spermatogenic cells was decreased with down-regulation of cyclin E and CDK2 and up-regulation of p53 and p21 expression, while apoptosis of spermatogenic cells was increased with up-regulation of Bax and p-caspase 3 expression and down-regulation of Bcl-xl expression. When serum calcium and phosphorus were normalized by the rescue diet, the defective reproductive phenotype in the male 1?(OH)ase(-/-) mice, including the hypergonadotropic hypogonadism, decreased sperm count and motility, histological abnormalities of testis and defective spermatogenesis were reversed. These results indicate that the infertility seen in male 1,25(OH)2D3-deficient mice is not a direct effect of active vitamin D deficiency on the reproductive system but is an indirect effect mediated by extracellular calcium and phosphorus.
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Porous single-crystalline palladium nanoflowers with enriched {100} facets for highly enhanced ethanol oxidation.
Nanoscale
PUBLISHED: 11-05-2014
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Palladium porous single-crystalline nanoflowers (PSNFs) with enriched high catalytic activity {100} facets were synthesized using a mild and controllable seed mediated growth method. The growth mechanism of the Pd PSNFs was investigated using time dependent morphology evolution through TEM imaging. Due to the specific structure, Pd PSNFs show highly enhanced ethanol oxidation reaction (EOR) activity, high EOR anti-poisoning and stability, much better than Pd nanocubes, {111} facets dominated dendritic urchin-like Pd nanoparticles and Pd black.
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Expression of calcineurin in podocytes in response to endoplasmic reticulum stress in diabetic nephropathy.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 11-01-2014
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Objective To investigate the regulation of calcineurin (CaN) by endoplasmic reticulum stress(ERS)in podocytes in vitro and in vivo at the stage microalbuminuria in diabetic nehropathy(DN). Methods The urinary albumin excretions of C57BLKS/J(Lepr) db/db and db/m mice at the ages of 6,9,and 12 weeks were measured. The expressions of CaN and synaptopodin of these mice were observed. In immortalized mouse podocytes,the expression of podocyte CaN incubated with different concentrations of paltimate was quantitatively determined by real-time PCR. The changes of CaN incubated with paltimate with or without ursodeoxy-cholic acid (UDCA) were analyzed by confocal microscopy and Western blotting. Results As urine protein increased,the expression of CaN was enhanced and the expression of synaptopodin was reduced in early stage DN db/db mice potocytes.In immortalized mouse podocytes,as the concentrations of palmitate increased,CaN mRNA increased. By confocal microscopy,the fluorescence intensity of CaN increased in palmitate treatment group.After co-incubation with palmitate and UDCA,the fluorescence intensity decreased. The similar results were shown by Western blotting. Conclusion At the stage of microalbuminuria in DN,ERS in podocytes up-regulates the expression of CaN.
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Identification of a juxtamembrane mechano-sensitive domain in the platelet mechanosensor glycoprotein Ib-IX complex.
Blood
PUBLISHED: 11-01-2014
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How glycoprotein (GP)Ib-IX complex on the platelet surface senses the blood flow through its binding to the plasma protein von Willebrand factor (VWF) and transmits a signal into the platelet remains unclear. Here we show that optical tweezer-controlled pulling of A1 domain of VWF (VWF-A1) on GPIb-IX captured by its cytoplasmic domain induced unfolding of a hitherto unidentified structural domain prior to the dissociation of VWF-A1 from GPIb-IX. Additional studies using recombinant proteins and mutant complexes confirmed its existence in GPIb-IX and enabled localization of this quasi-stable mechano-sensitive domain of ~60 residues between the macroglycopeptide region and the transmembrane helix of GPIb? subunit. These results suggest that VWF-mediated pulling under fluid shear induces unfolding of the mechano-sensitive domain in GPIb-IX, which may possibly contribute to platelet mechanosensing and/or shear resistance of VWF-platelet interaction. The identification of the mechano-sensitive domain in GPIb-IX has significant implications for the pathogenesis and treatment of related blood diseases.
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Understanding the Structure of Hydrophobic Surfactants at the Air/Water Interface from Molecular Level.
Langmuir
PUBLISHED: 10-31-2014
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Understanding the behavior of fluorocarbon surfactants at the air/water interface is crucial for many applications, such as lubricants, paints, cosmetics, and fire-fighting foams. In this study, molecular dynamics (MD) simulations were employed to investigate the microscopic properties of non-ionic fluorocarbon surfactants at the air/water interface. Several properties, including the distribution of head groups, the distribution probability of the tilt angle between hydrophobic tails with respect to the xy plane, and the order parameter of surfactants, were computed to probe the structure of hydrophobic surfactants at the air/water interface. The effects of the monomer structure on interfacial phenomena of non-ionic surfactants were investigated as well. It is observed that the structure of fluorocarbon surfactants at the air/water interface is more ordered than that of hydrocarbons, which is dominated by the van der Waals interaction between surfactants and water molecules. However, replacing one or two CF2 with one or two CH2 group does not significantly influence the interfacial structure, suggesting that hydrocarbons may be promising alternatives to perfluorinated surfactants.
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Driving Fatigue in Professional Drivers: A Survey of Truck and Taxi Drivers.
Traffic Inj Prev
PUBLISHED: 10-31-2014
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ABSTRACT Objectives: Fatigue among truck drivers has been studied extensively; however, less is known regarding the fatigue experience of taxi drivers in heavily populated metropolitan areas. This study aimed to compare the differences and similarities between truck and taxi driver fatigue to provide implications for the fatigue management and education of professional drivers. Methods: A sample of 274 truck drivers and 286 taxi drivers in Beijing was surveyed via a questionnaire, which included items regarding work characteristics, fatigue experience, accident information, attitude toward fatigue, and methods of counteracting fatigue. Results: Driver fatigue was prevalent among professional drivers, and it was even more serious for taxi drivers. Taxi drivers reported more frequent fatigue experiences and were involved in more accidents. Among the contributing factors to fatigue, prolonged driving time was the most important factor identified by both driver groups. Importantly, the reason for the engagement in prolonged driving was neither due to the lack of awareness concerning the serious outcome of fatigue driving nor because of their poor detection of fatigue. The most probable reason was the optimism bias, as a result of which, these professional drivers thought fatigue was more serious for other drivers than for themselves, and they thought that they were effective in counteracting the effect of fatigue on their driving performance. Moreover, truck drivers tended to take the methods that require stopping to counteract fatigue, whereas taxi drivers preferred the methods that were simultaneous with driving. Although both driver groups considered taking a nap as one of the most effective means to address fatigue, this method was not commonly used among them. Interestingly, these drivers were aware that the methods they frequently used were not the most effective means to counteract fatigue. Conclusions: This study provides knowledge on truck and taxi drivers' characteristics in fatigue experience, fatigue attitude, and fatigue countermeasures, and these findings have practical implications for the fatigue management and education of professional drivers.
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Involvement of FoxQ1 in NSCLC through regulating EMT and increasing chemosensitivity.
Oncotarget
PUBLISHED: 10-31-2014
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Forkhead box Q1 (FoxQ1) is a member of the forkhead transcription factor family. High expression of FoxQ1 has been associated with several cancers including non-small cell lung cancer (NSCLC), but its role in the development of NSCLC is not clear. In this study, we investigated the effect of FoxQ1 up-regulated and down-regulated in vitro and in vivo, and the role of FoxQ1 in regulating epithelial-mesenchymal transition (EMT) in NSCLC, providing evidence that FoxQ1 could be a potential therapeutic target in NSCLC. NSCLC cells with silenced FoxQ1 had decreased cell proliferation, migration and invasion in cell culture and delayed growth of xenograft tumors in mice compared with corresponding control cells. The NSCLC cells downregulated for FoxQ1 induced the expression of apoptosis-associated proteins and reduction of anti-apoptotic protein expression. Downregulation of FoxQ1 promoted the expression of epithelial markers and decreased several mesenchymal markers in vitro and in vivo. In addition, FoxQ1 was associated with resistance to conventional chemotherapeutic agents. In contrast, FoxQ1 overexpressed elicited converse effects on these phenotypes in vitro and in vivo. Our findings define a key role for FoxQ1 in regulating EMT and increasing chemosensitivity in NSCLC.
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Synthesis of Multisubstituted Pyrroles from Doubly Activated Cyclopropanes Using an Iron-Mediated Oxidation Domino Reaction.
J. Org. Chem.
PUBLISHED: 10-31-2014
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An alternative route has been developed for the construction of multisubstituted pyrrole derivatives from readily available, doubly activated cyclopropanes and anilines using an iron-mediated oxidation domino reaction (i.e., sequential ring-opening, cyclization, and dehydrogenation reactions). This reaction uses readily available reactants and is tolerant of a broad range of substrates, with the desired products being formed in good to excellent yields.
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Biased multicomponent reactions to develop novel bromodomain inhibitors.
J. Med. Chem.
PUBLISHED: 10-31-2014
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BET bromodomain inhibition has contributed new insights into gene regulation and emerged as a promising therapeutic strategy in cancer. Structural analogy of early methyl-triazolo BET inhibitors has prompted a need for structurally dissimilar ligands as probes of bromodomain function. Using fluorous-tagged multicomponent reactions, we developed a focused chemical library of bromodomain inhibitors around a 3,5-dimethylisoxazole biasing element with micromolar biochemical IC50. Iterative synthesis and biochemical assessment allowed optimization of novel BET bromodomain inhibitors based on an imidazo[1,2-a]pyrazine scaffold. Lead compound 32 (UMB-32) binds BRD4 with a Kd of 550 nM and 724 nM cellular potency in BRD4-dependent lines. Additionally, compound 32 shows potency against TAF1, a bromodomain-containing transcription factor previously unapproached by discovery chemistry. Compound 32 was cocrystallized with BRD4, yielding a 1.56 Å resolution crystal structure. This research showcases new applications of fluorous and multicomponent chemical synthesis for the development of novel epigenetic inhibitors.
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EPR detection of hydroxyl radical generation and oxidative perturbations in lead-exposed earthworms (Eisenia fetida) in the presence of decabromodiphenyl ether.
Ecotoxicology
PUBLISHED: 10-28-2014
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Lead (Pb) and decabromodiphenyl ether (BDE209) are the main contaminants at e-waste recycling sites, and their potential toxicological effects on terrestrial organisms have received extensive attention. However, the impacts on the oxidative perturbations and hydroxyl radical (·OH) generation in earthworms of exposure to the two chemicals remain almost unknown. Therefore, indoor incubation tests were performed on control and contaminated soil samples to determine the effects of Pb in earthworms Eisenia fetida in the presence of BDE209 through the use of several biomarkers in microcosms. The results have demonstrated that the addition of BDE209 (1 or 10 mg kg(-1)) decreased the enzymatic activities [superoxide dismutase, catalase (CAT), peroxidase] and total antioxidant capacity (T-AOC) compared with exposure to BDE209 alone (50, 250 or 500 mg kg(-1)). Electron paramagnetic resonance spectra indicated that ·OH radicals in earthworms were significantly induced by Pb in the presence of BDE209. The changing pattern of malondialdehyde (MDA) contents was accordant with that of ·OH intensity suggested that reactive oxygen species might lead to cellular lipid peroxidation. Furthermore, CAT exhibited more sensitive response to single Pb exposure than the other biomarkers, while T-AOC, ·OH and MDA might be three most sensitive biomarkers in earthworms after simultaneous exposure to Pb and BDE209. The results of these observations suggested that oxidative stress appeared in E. fetida, and it may play an important role in inducing the Pb and BDE209 toxicity to earthworms.
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Conformation Modulated Optical Activity Enhancement in Chiral Cysteine and Au Nanorod Assemblies.
J. Am. Chem. Soc.
PUBLISHED: 10-28-2014
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Assemblies of chiral cysteine (CYS) and Au nanorods (GNRs) are constructed in two typical patterns, end-to-end and side-by-side. Impressively, side-by-side assembled GNRs with CYS show obviously stronger plasmonic circular dichrosim (CD) response compared with the end-to-end assemblies. The corresponding theoretical calculation elucidates the intrinsic relationship among geometric structure, electromagnetic interaction, and induced plasmonic CD of the assemblies. This work will significantly benefit the design and application of plasmonic nanodevices with controllable chiroptical responses.
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[Clinicopathological significance of Sox17 and ?-catenin protein of Wnt in oligodendroglioma].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 10-28-2014
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To investigate the expression of Sox17 and ?-catenin proteins in oligodendroglioma, and its clinical significance.
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[Clinicopathologic features and prognosis of T lymphoblastic lymphoma associated with Langerhans cell histiocytosis].
Zhonghua Bing Li Xue Za Zhi
PUBLISHED: 10-28-2014
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To study the clinicopathologic features, immunophenotype and molecular genetic changes of T lymphoblastic lymphoma (T-LBL) associated with Langerhans cell histiocytosis (LCH).
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Thickness dependence of ice removal stress for a polydimethylsiloxane nanocomposite: sylgard 184.
Langmuir
PUBLISHED: 10-27-2014
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Minimizing adhesion of ice has been the subject of extensive studies because of importance to applications such aircraft wings, spacecraft, and power transmission wires. A growing interest concerns coatings for wind turbine blades and refrigeration. Herein, a new laboratory test was employed to obtain the thickness dependence of ice adhesion for Sylgard 184-a filled polydimethylsiloxane elastomer. A correlation between ice adhesion and coating thickness (t) was found that follows a relationship developed by Kendall over 40 years ago for removal of a rigid object from an elastomer. With a 0.05 mm/s probe speed a nearly linear relationship between peak removal stress (Ps) and 1/t(1/2) was obtained with Ps ? 460 kPa for an 18 ?m coating, decreasing to ?120 kPa for 533 ?m. Preliminary results suggest that below ?10 ?m Ps departs from the 1/t(1/2) correlation while above ?500 ?m a limiting value for Ps may be reached. We previously reported that probe speed has negligible effect on the glassy polymer PMMA. In contrast, probe speed is identified as an important variable for testing ice release on elastomeric Sylgard 184 coatings. While work of adhesion, which is related to surface free energy, is recognized as an important factor that can affect ice release, the results reported herein show that coating thickness can override this single parameter for elastomeric substrates.
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Multiplexed microfluidic blotting of proteins and nucleic acids by parallel, serpentine microchannels.
Lab Chip
PUBLISHED: 10-25-2014
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This work develops a high-throughput, high-efficiency and straightforward microfluidic blotting method for analyzing proteins and nucleic acids. Sample solutions containing antibodies (for protein detection) or hybridization probes (for nucleic acid detection) are introduced into the parallel, serpentine microchannels to specifically recognize the immobilized targets on the substrate, achieving the identification of multiple targets in multiple samples simultaneously. The loading control, molecular weight markers, and antigen/antibody titration are designed and integrated into the microfluidic chip, thus allowing for the quantification of proteins and nucleic acids. Importantly, we could easily distinguish the adjacent blotting bands inside parallel microchannels, which may be difficult to achieve in conventional blotting. The small dimensions of microfluidic channels also help to reduce the amount of probing molecules and to accelerate the biochemical reaction. Our microfluidic blotting could bypass the steps of blocking and washing, further reducing the operation time and complexity.
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[Clinical analysis of 14 cases with primary breast lymphoma].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 10-24-2014
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To analyze the clinical features, prognostic factors, diagnostic methods and treatment outcomes of primary breast lymphoma (PBL).
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[Treatment of calcaneal fractures by fixation of Kirschner needle and thread cancellous bone screw through sinus tarsi interstice].
Zhongguo Gu Shang
PUBLISHED: 10-24-2014
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To explore the effect of fixation of Kirschner needle and thread cancellous bone screw through the sinus tarsi interstice for the treatment of calcaneal fractures.
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[Controlled observation of clinical efficacy on cervical spondylosis of neck type treated with scraping and acupuncture].
Zhongguo Zhen Jiu
PUBLISHED: 10-23-2014
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To observe the clinical efficacy difference between segmentation scraping and conventional acupuncture for cervical spondylosis (CS) so as to provide effective treatment method.
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Multidimensional analysis of gene expression reveals TGFB1I1-induced EMT contributes to malignant progression of astrocytomas.
Oncotarget
PUBLISHED: 10-22-2014
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Malignant progression of astrocytoma is a multistep process with the integration of genetic abnormalities including grade progression and subtypes transition. Established biomarkers of astrocytomas, like IDH1 and TP53 mutation, were not associated with malignant progression. To identify new biomarker(s) contributing to malignant progression, we collected 252 samples with whole genome mRNA expression profile [34 normal brain tissue (NBT), 136 grade II astrocytoma (AII) and 82 grade III astrocytoma (AIII)]. Bioinformatics analysis revealed that EMT-associated pathways were most significantly altered along with tumor grades progress with up-regulation of 17 genes. Up-regulation of these genes was further confirmed by RNA-sequencing in 128 samples. Survival analysis revealed that high expression of these genes indicates a poor survival outcome. We focused on TGFB1I1 (TGF-?1 induced transcript 1) whose expression correlation with WHO grades was further validated by qPCR in 6 cell lines of different grades and 49 independent samples (36 AIIs and 13 AIIIs). High expression of TGFB1I1 was found associated with subtype transition and EMT pathways activation. The conclusion was confirmed using immunohistochemistry in tissue microarrays. Studies in vitro and vivo using TGF-?1 and TGFB1I1 shRNA demonstrated that TGFB1I1 is required for TGF-? stimulated EMT that contributes to malignant progression of astrocytomas.
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Hydrogen sulfide extends the postharvest life and enhances antioxidant activity of kiwifruit during storage.
J. Sci. Food Agric.
PUBLISHED: 10-21-2014
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Exogenous hydrogen sulfide (H2S) treatment can prolong the postharvest life of cut flowers and strawberries. Little work has been done to explore the effects of H2S on respiratory climacteric fruits such as kiwifruits during storage. Therefore the aim of the present study was to evaluate the effects of H2S treatment at concentrations of 15–1000 µmol L?1 on the postharvest life of kiwifruit during 25 °C storage and the role of H2S in regulating the antioxidant defensive system of kiwifruit.
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[Establishment and biological characteristics of a platinum-resistance nude mouse model in epithelial ovarian cancer].
Zhonghua Fu Chan Ke Za Zhi
PUBLISHED: 10-21-2014
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To establish a platinum resistance nude mice model of epithelial ovarian cancer (EOC) and investigate its resistance to cisplatin (DDP) biological characteristics, so as to provide evidences for exploring chemoresistence mechanisms and screening for reversal targets in vivo micro-environment.
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Binding Difference of Fipronil with GABAARs in Fruitfly and Zebrafish: Insights from Homology Modeling, Docking, and Molecular Dynamics Simulation Studies.
J. Agric. Food Chem.
PUBLISHED: 10-21-2014
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Fipronil, which targets GABAA receptors (GABAARs), is the first phenylpyrazole insecticide widely used in crop protection and public hygiene. However, its high toxicity on fishes greatly limited its applications. In the present study, a series of computational methods including homology modeling, docking, and molecular dynamics simulation studies were integrated to explore the binding difference of fipronil with GABAARs from fruitfly and zebrafish systems. It was found that, in the zebrafish system, the H-bond between 6'Thr and fipronil exerted key effects on the recognition of fipronil, which was absent in the fruitfly system. On the other hand, in the fruitfly system, strong electrostatic interaction between 2'Ala and fipronil was favorable to the binding of fipronil but detrimental to the binding in the zebrafish system. These findings marked the binding difference of fipronil with different GABAARs, which might be helpful in designing selective insecticides against pests instead of fishes.
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[The interaction between ononin and human intestinal bacteria].
Yao Xue Xue Bao
PUBLISHED: 10-18-2014
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The study aims to screen the ability of the bacteria to metabolize ononin and assess the effect of ononin on the intestinal bacteria. Fresh human fecal sample was obtained from a healthy volunteer, diluted serially in sterile water and sixty-nine different bacterial colonies were picked out ultimately. UPLC-Q-TOF/MS with automated data analysis software (MetaboLynx) was applied to fast analysis of ononin metabolites. Furthermore, an E(max) precision microplate reader was employed to determine the growth situation of Enterococcous sp., Enterobacter sp., Lactobacilli sp., and Bifidobacteria sp. Results indicated that hydrogenation, demethylation, hydroxylation and deglycosylation were the major metabolic pathways of ononin by human intestinal bacteria in vitro. Ononin can inhibit the growth of pathogen such as Enterococcus sp., Enterobacter sp. and can promote the growth of probiotics such as Bifidobacteria sp. and Lactobacilli sp. This study suggested that intestinal bacteria have the metabolic effects of ononin and the biotransformation was completed by different bacteria. And ononin can affect the balance of intestinal flora and the degree of influence varies depending on the bacterial species and the concentration of ononin.
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Highly efficient second harmonic generation of a light carrying orbital angular momentum in an external cavity.
Opt Express
PUBLISHED: 10-17-2014
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Traditional methods for generating a light carrying orbital angular momentum (OAM) include the use of holographic diffraction gratings, vortex phase plates and spatial light modulators. Here we report a new method for highly efficient second-harmonic generation (SHG) of a light with OAM. By properly aligning an external cavity that contains a quasi-phase matching nonlinear crystal and pumping it with a light carrying OAM, mode matching between the pump light and the cavity's higher order Laguerre-Gaussian (LG) mode is achieved, SHG with a conversion efficiency of up to 10.3% is obtained. We have demonstrated for the first time that the cavity can stably operate at its higher order LG mode similar to that of a Gaussian mode. The second harmonic generated light has an OAM value that is double with respected to the OAM value of the pump light. The parameters that affect the beam quality and conversion efficiency are discussed in detail. Our work opens a brand new field in laser optics and makes the first step toward high efficiency processing using a light carrying OAM.
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Q-switched mode-locked erbium-doped fiber laser based on topological insulator Bi2Se3 deposited fiber taper.
Appl Opt
PUBLISHED: 10-17-2014
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We have demonstrated the passive Q-switching mode-locking operation in an erbium-doped fiber (EDF) laser by using topological insulator Bi2Se3 deposited on fiber taper, whose damage threshold can be further increased by the large evanescent field interacting length. Due to the low saturation intensity, stable Q-switched mode-locked fiber lasers centered at 1562 nm can be generated at a pump power of 10 mW. The temporal and spectral characteristics for different pump strengths have also been investigated. To the best of our knowledge, it is the first time a Q-switched mode-locked EDF laser based on the fiber taper deposited by Bi2Se3 was generated.
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Cellular retinoic acid-binding protein 2 inhibits tumor growth by two distinct mechanisms.
J. Biol. Chem.
PUBLISHED: 10-17-2014
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Cellular retinoic acid-binding protein 2 (CRABP2) potently suppresses the growth of various carcinomas but the mechanism(s) that underlie this activity remain incompletely understood. CRABP2 displays two distinct functions: the classical function of this protein is to directly deliver retinoic acid (RA) to RAR, a nuclear receptor activated by this hormone, in turn inducing the expression of multiple anti-proliferative genes. The other function of the protein is exerted in the absence of RA and mediated by the RNA-binding and stabilizing protein HuR. CRABP2 directly binds to HuR, markedly strengthens its interactions with target mRNAs, and thus increases their stability and upregulates their expression. Here we show that the anticarcinogenic activities of CRABP2 are mediated by both of its functions. Transcriptome analyses revealed that, in the absence of RA, a large cohort of transcripts are regulated in common by CRABP2 and HuR and many of these are involved in regulation of oncogenic properties. Furthermore, both in cultured cells and in vivo, CRABP2 or a CRABP2 mutant defective in its ability to cooperate with RAR but competent in interactions with HuR, suppressed carcinoma growth and did so in the absence of RA. Hence, transcript stabilization by the CRABP2-HuR complex significantly contributes to the ability of CRABP2 to inhibit tumorigenesis. Surprisingly, the observations also revealed that HuR regulates the expression of multiple genes involved in nuclear pore formation and is required for nuclear import of CRABP2 and for transcriptional activation by RAR. The data thus point at a novel function for this important protein.
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Effects of Lettuce Glycoside B in Ameliorating Pulmonary Fibrosis Induced by Irradiation Exposure and its Anti-Oxidative Stress Mechanism.
Cell Biochem. Biophys.
PUBLISHED: 10-17-2014
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The present research assessed the effects of lettuce glycoside B (LGB), a compound separated and purified from Pterocypsela laciniata, on irradiation-induced pulmonary fibrosis and explored the mechanism involved. Animal model of irradiation exposure inducing pulmonary fibrosis was established by Co irradiator. Rats were intraperitoneally treated with LGB (100, 200 and 400 mg/kg) once per day for a month. Lung index data were analyzed. The levels of fibrosis were assessed by hydroxyproline (Hyp) of pulmonary and lung tissue sections after irradiation exposure. Alveolitis and fibrosis levels were calculated from semi-quantitative analysis of hematoxylin and eosin and Masson's trichrome lung section staining. The serum levels of transforming growth factor ?1 (TGF-?1), interleukin (IL)-6, and tumor necrosis factor-? (TNF-?) were also evaluated. Antioxidant enzymes of superoxide dismutase (SOD) were measured in serum. Moreover, we also measured serum malondialdehyde (MDA) levels, a marker of oxidative stress. Treatment with LGB significantly reduced mortality rates and lung index scores and MDA content, enhanced SOD and other antioxidant enzymes activity, and regulated serum levels of TGF-?1, IL-6, and TNF-?. These results demonstrated that LGB significantly inhibited irradiation-induced pulmonary fibrosis. Furthermore, the results suggested promising clinical effect of LGB therapies for treating irradiation-induced pulmonary fibrosis.
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Association of toll-like receptor 4 signaling pathway with steroid-induced femoral head osteonecrosis in rats.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 10-16-2014
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Osteonecrosis of the femoral head is frequently observed in patients treated with excessive corticosteroids. However, the pathogenesis of corticosteroid-induced osteonecrosis remains unclear. The purpose of this study was to investigate the role of Toll-like receptor 4 (TLR4) signaling pathway in steroid-induced femoral head osteonecrosis in rats. Male Sprague-Dawley rats were injected intramuscularly with 20 mg/kg methylprednisolone (MP) for 8 weeks, twice per week. The animals were sacrificed at 2, 4 and 8 weeks after the last MP injection, respectively, and then allocated to the 2-, 4- and 8-week model groups (n=24 each). Rats in the control group (n=12) were not given any treatment. Histopathological analysis was performed and the concentration of tartrate-resistant acid phosphatase (TRAP) in plasma was determined. The activation of osteoclasts in the femoral head was assessed by TRAP staining. The expression of TLR4, MyD88, TRAF6 and NF-?B p65 that are involved in TLR4 signaling, and MCP-1 production were detected by using real-time PCR (RT-PCR) and Western blotting. The results showed that the osteonecrosis in the femoral head was clearly observed and the concentration of TRAP in the plasma was increased in the model rats. The femoral head tissues in MP-treated rats were positive for TRAP and the intensity of TRAP staining was greater in MP-treated rats than in control rats. As compared with the control group, the mRNA expression of TLR4 signaling-related factors was enhanced significantly at 4 and 8 weeks, and the protein levels of these factors increased significantly with time. It was concluded that MP could induce the femoral head osteonecrosis in rats, which was associated with osteoclast activation via the TLR4 signaling pathway. These findings suggest that TLR4 signaling pathway plays a pivotal role in the pathogenesis of steroid-induced osteonecrosis.
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[Logistic regression analysis on risk factors of cerebral hemorrhage complicated with stress ulcer].
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
PUBLISHED: 10-16-2014
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To explore the related risk factors of cerebral hemorrhage complicated with stress ulcer (SU).
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Remarkable increase in luminol electrochemiluminescence by sequential electroreduction and electrooxidation.
Chem. Commun. (Camb.)
PUBLISHED: 10-16-2014
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Luminol electrochemiluminescence is dramatically increased by about five hundred times by taking full advantage of both electrochemical reduction and electrochemical oxidation using simple linear sweep voltammetry, leading to sensitive detection.
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[The spatiotemporal frequency tuning of pattern visual evoked potentials in rats].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 10-15-2014
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To observe the spatiotemporal frequency tuning of pattern visual evoked potentials in Wistar rats.
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[The effect of superior oblique recession on the status of ocular torsion].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 10-15-2014
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To investigate the effect of superior oblique recession on the status of ocular torsion.
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[Clinical investigation on AC/A ratio in intermittent exotropia coexisting with ametropia].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 10-15-2014
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To investigate AC/A ratio and coexisting ametropia in intermittent exotropia. To discuss the relation between AC/A ratio and the development of intermittent exotropia.
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Non-antiplatelet effect of Clopidogrel: Improving endothelial function in Chinese healthy subjects with different CYP2C19 genotype.
Clin. Exp. Pharmacol. Physiol.
PUBLISHED: 10-15-2014
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Clopidogrel has been demonstrated to improve endothelial function in vitro and in patients with coronary artery disease (CAD). But it remains unclear whether such an effect of clopidogrel is associated with CYP2C19 polymorphisms which determines the antiplatelet effect of clopidogrel.
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Acute brucellosis with typical hemophagocytic lymphohistiocytosis accompanying elevated tumor markers.
Arch Iran Med
PUBLISHED: 10-13-2014
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We reported a typical brucellosis, which was diagnosed as hemophagocytic lymphohistiocytosis (HLH). Although some tumor markers (CEA, CYFRA21-1, NSE, CA19-9) in the patient's serum were elevated, carcinomas were excluded by a variety of inspections including bone marrow aspirations, ultrasound examinations, and whole-body PET-CT scans. It was concluded that serum tumor markers are considered medically necessary as a screening test for brucellosis with HLH, however, detailed inspections were needed to make a final diagnosis. Moreover, combination of epidemiology investigations and laboratory inspections were helpful to determine the etiology of HLH and initiate the corresponding treatments.
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Crystal Structure of the Human Fatty Acid Synthase Enoyl-Acyl Carrier Protein-Reductase Domain Complexed with Triclosan Reveals Allosteric Protein-Protein Interface Inhibition.
J. Biol. Chem.
PUBLISHED: 10-11-2014
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Human fatty acid synthase (FAS) is a large, multidomain protein that synthesizes long-chain fatty acids. Since these fatty acids are primarily provided by diet, FAS is normally expressed at low levels; however, it is highly upregulated in many cancers. Human enoyl-acyl carrier protein-reductase (hER) is one of the FAS catalytic domains and its inhibition by drugs like triclosan (TCL) can increase cytotoxicity and decrease drug resistance in cancer cells. We have determined the structure of hER in the presence and absence of TCL. TCL was not bound in the active site, as predicted, but rather at the protein-protein interface (PPI). TCL binding induces a dimer orientation change that causes downstream structural rearrangement in critical active site residues. Kinetics studies indicate that TCL is capable of inhibiting the isolated hER domain with an IC50 of approximately 55 ?M. Given the hER-TCL structure and the inhibition observed in the hER domain, it seems likely that TCL is observed in the physiologically relevant binding site and that it acts as an allosteric PPI inhibitor. TCL may be a viable scaffold for the development of anti-cancer PPI FAS inhibitors.
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Age-Triggered and Dark-Induced Leaf Senescence Require the bHLH Transcription Factors PIF3, 4 and 5.
Mol Plant
PUBLISHED: 10-08-2014
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Leaf senescence can be triggered and promoted by a large number of developmental and environmental factors. Numerous lines of evidence have suggested an involvement of phytochromes in the regulation of leaf senescence, but the related signaling pathways and physiological mechanisms are poorly understood. In this study, we initially identified phytochrome-interacting factors (PIFs) 3, 4 and 5 as putative mediators of leaf senescence. Mutations of the PIF genes resulted in a significantly enhanced leaf longevity in age-triggered and dark-induced senescence, whereas overexpressions of these genes accelerated age-triggered and dark-induced senescence in Arabidopsis. Consistently, loss-of-function of PIF4 attenuated dark-induced transcriptional changes associated with chloroplast deterioration and ROS generation. ChIP-PCR and Dual-Luciferase assays demonstrated that PIF4 can activate chlorophyll degradation regulatory gene NYE1 and repress chloroplast activity maintainer gene GLK2 by binding to their promoter regions. Finally, dark-induced ethylene biosynthesis and ethylene-induced senescence were both dampened in pif4, suggesting the involvement of PIF4 in both ethylene biosynthesis and signaling pathway. Our study provides evidence that PIF3, 4 and 5 are novel positive senescence mediators and gains an insight into the mechanism of light signaling involved in the regulation of leaf senescence.
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Phosphotransferase System-Dependent Extracellular Growth of Listeria monocytogenes Is Regulated by Alternative Sigma Factors ?L and ?H.
Appl. Environ. Microbiol.
PUBLISHED: 10-03-2014
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Alternative sigma (?) factors and phosphotransferase systems (PTSs) play pivotal roles in the environmental adaptation and virulence of Listeria monocytogenes. The growth of the L. monocytogenes parent strain 10403S and 15 isogenic alternative ? factor mutants was assessed in defined minimal medium (DM) with PTS-dependent or non-PTS-dependent carbon sources at 25°C or 37°C. Overall, our results suggested that the regulatory effect of alternative ? factors on the growth of L. monocytogenes is dependent on the temperature and the carbon source. One-way analysis of variance (one-way ANOVA) showed that the factor "strain" had a significant effect on the maximum growth rate (?max), lag phase duration (?), and maximum optical density (ODmax) in PTS-dependent carbon sources (P < 0.05) but not in a non-PTS-dependent carbon source. Also, the ODmax was not affected by strain for any of the three PTS-dependent carbon sources at 25°C but was affected by strain at 37°C. Monitoring by quantitative real-time PCR (qRT-PCR) showed that transcript levels for lmo0027, a glucose-glucoside PTS permease (PTS(Glc)-1)-encoding gene, were higher in the absence of ?(L), and lower in the absence of ?(H), than in the parent strain. Our data thus indicate that ?(L) negatively regulates lmo0027 and that the increased ?max observed for the ?sigL strain in DM with glucose may be associated with increased expression of PTS(Glc)-1 encoded by lmo0027. Our findings suggest that ?(H) and ?(L) mediate the PTS-dependent growth of L. monocytogenes through complex transcriptional regulations and fine-tuning of the expression of specific pts genes, including lmo0027. Our findings also reveal a more important and complex role of alternative ? factors in the regulation of growth in different sugar sources than previously assumed.
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[Study on safety and feasibility of minimally invasive esophagectomy without the use of postoperative nasogastric tube decompression].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 10-03-2014
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To investigate the safety and feasibility of forgoing postoperative nasogastric tube decompression in minimally invasive esophagectomy for patients with esophagus carcinoma.
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[Two types of digestive tract reconstruction after proximal gastrectomy for early gastroesophageal junction adenocarcinoma: a randomized controlled study].
Zhonghua Wei Chang Wai Ke Za Zhi
PUBLISHED: 10-03-2014
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To investigate the better method of digestive tract reconstruction in proximal gastrectomy for early gastroesophageal junction adenocarcinoma.
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[Isolation, identification of TJ430 strain and characterization of its antifungal metabolite].
Wei Sheng Wu Xue Bao
PUBLISHED: 10-03-2014
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To screen new agro-antibiotics, rare actinomycetes were isolated by improved separation methods from soil samples and the chemical structure of the antifungal active product was elucidated.
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[Complete genomic analysis of a novel infectious bronchitis virus isolate].
Bing Du Xue Bao
PUBLISHED: 10-03-2014
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The genome of CK/CH/SD09/005, an isolate of infectious bronchitis virus (IBV), was characterized to enable the further understanding of the epidemiology and evolution of IBV in China. Twenty-five pairs of primers were designed to amplify the full-length genome of CK/CH/SD09/005. The nucleotide sequence of CK/CH/SD09/005 was compared with reference IBV strains retrieved from GenBank. The phylogenic relationship between CK/CH/SD09/005 and the reference strains was analyzed based on S1 gene sequences. The complete genome of CK/CH/SD09/005 consisted of 27691 nucleotides (nt), excluding the 5' cap and 3' poly A tail. The whole-genome of CK/CH/SD09/005 shared 97 - 99% nucleotide sequence homology with the GX-NN09032 strain, which was the only complete genome that was closely related to CK/CH/SD09/005. When compared with all reference strains except GX-NN09032, CK/CH/SD09/005 showed the highest similarity to ck/CH/LDL/091022 and SDIB821/2012 (QX-like) in the replicase gene (Gene 1) and 3'UTR, with a sequence identity rate of 97% and 98%, respectively. However, CK/CH/SD09/005 exhibited lower levels of similarity with ck/CH/LDL/091022 and SDIB821/2012 in S-3a-3b-3c/ E-M-5a-5b-N with a sequence identity of 72% - 90%. CK/CH/SD09/005 showed the highest level of nucleotide identity with Korean strain 1011, and Chinese strains CK/CH/LXJ/02I, DK/CH/HN/ZZ2004 and YX10, in ORF 3c/E (97%), 5a (96%), 5b (99%) and N (96%), respectively. ORFs 3a, 3b and M of CK/CH/SD09/005 exhibited no more than 90% homology with the reference strains, excluding GX-NN09032. The phylogenic analysis based on the S1 gene revealed that CK/CH/SD09/005 and 39 published strains were classified into seven clades (genotypes). CK/CH/SD09/005 was distributed in clade IV with several isolates collected between 2007 and 2012. CK/CH/SD09/005 showed 66% - 69% and 72% - 81% nucleotide identities with the IBV strains of other six clades in the S1 and S2 subunits, respectively. More over, multiple substitutions were found throughout the entire S gene of CK/CH/SD09/005, while insertions and deletions were located within the S1 gene. These results indicated that CK/CH/SD09/005 is a novel variant that may be derived from the QX-like strains that are prevalent in China. Multiple genetic mechanisms, including recombinations, mutations, insertions and deletions, are likely to have contributed to the emergence of this IBV strain.
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Down-regulation of connexin43 and connexin32 in keratocystic odontogenic tumours: potential association with clinical features.
Histopathology
PUBLISHED: 10-02-2014
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The objective of this study was to explore the potential involvement of connexin43 (Cx43) and connexin32 (Cx32), two vital members of the connexin families, in the pathogenesis of keratocystic odontogenic tumours (KCOT).
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Split of Descemet's membrane and pre-Descemet's layer in fungal keratitis: new definition of corneal anatomy bringing in new knowledge of fungi infection.
Histopathology
PUBLISHED: 10-02-2014
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In 2013, Dua defined a novel pre-Descemet posterior stromal layer (PDL) in human cornea, which challenged the general knowledge about human corneal anatomy [1]. According to Dua's report PDL was a layer of amorphous extracellular matrix between stroma and Descemet's membrane (DM), and he separated the layer by injecting air into posterior cornea. This article is protected by copyright. All rights reserved.
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[Changes of Mu-opioid receptor and neuron-restrictive silencer factor in periaquductal gray in mouse models of remifentanil-induced postoperative hyperalgesia].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 10-02-2014
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To determine the changes of Mu-opioid receptor (Mor) and neuron-restrictive silencer factor (NRSF) in periaquductal gray (PAG) in mouse models of remifentanil-induced postoperative hyperalgesia.
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Pial arteriovenous fistulas associated with multiple aneurysms presenting as intracerebral hemorrhage: a case report.
Turk Neurosurg
PUBLISHED: 10-01-2014
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Intracranial pial arteriovenous fistulas (AVFs) associated with multiple aneurysms of the main feeding arteries are very rare cerebrovascular lesions. We report a unique case of pial AVFs associated with four aneurysms of the feeding anterior cerebral artery (ACA) which presented as intracerebral hemorrhage (ICH), intraventricular hemorrhage (IVH) and spontaneous subarachnoid hemorrhage (SAH). CT angiography (CTA) and digital subtraction angiography (DSA) images demonstrated clearly the direct connection without nidus between the first and second segment of right ACA accompanied by four irregular aneurysms and an abnormally dilated draining vein into the superior sagittal sinus (SSS). Owing to the superficial-seated fistulas, the morphology of feeding arteries and associated four aneurysms and intracranial hemorrhage, the lesions were surgically treated. Postoperative cerebral angiography certified closure of the fistulas and exclusion of the four aneurysms as well as disappearance of early venous drainage. However, subsequent precontrast brain CT showed hydrocephalus underwent left ventriculoperitoneal shunt placement.
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Clinical characteristics of human infection with a novel avian-origin influenza A(H10N8) virus.
Chin. Med. J.
PUBLISHED: 10-01-2014
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Novel influenza A viruses of avian-origin may be the precursors of pandemic strains. This descriptive study aims to introduce a novel avian-origin influenza A (H10N8) virus which can infect humans and cause severe diseases.
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[Clinical outcome of posterior approach 360° vertebral canal decompression for ossifying thoracic disc herniation].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 09-30-2014
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To evaluate the clinical results and the value of the posterior approach 360° vertebral canal decompression and transfacet discectomy combined with interbody fusion and pedicle screw internal fixation for the treatment of ossifying thoracic disc herniation.
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Study of ZHENG differentiation in hepatitis B-caused cirrhosis: a transcriptional profiling analysis.
BMC Complement Altern Med
PUBLISHED: 09-29-2014
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In traditional Chinese medicine (TCM) clinical practice, ZHENG (also known as TCM syndrome) helps to understand the human homeostasis and guide individualized treatment. However, the scientific basis of ZHENG remains unclear due to limitations of current reductionist approaches.
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Emodin azide methyl anthraquinone derivative induced G0/ G1 arrest in HER2/neu-overexpressing MDA-MB-453 breast cancer cells.
J BUON
PUBLISHED: 09-28-2014
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Our previous data have shown that emodin azide methyl anthraquinone derivative (AMAD) triggered mitochondrial- dependent cell apoptosis involving caspase-8-mediated Bid cleavage, and induced proteasomal degradation of HER2/neu by blocking Her2/neu binding to Hsp90. In the present study, we futher investigated the effect of this compound on the cell cycle and related molecular mechanisms in HER2/neu-overexpressing MDA-MB-453 breast cancer cells.
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Cigarette Smoke Attenuates the RIG-I-initiated Innate Antiviral Response to Influenza Infection in Two Murine Models.
Am. J. Physiol. Lung Cell Mol. Physiol.
PUBLISHED: 09-28-2014
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Cigarette smoke (CS) exposure increases the frequency and severity of respiratory tract infections. Despite this association, the mechanisms underlying the increased susceptibility to respiratory virus infection are poorly understood. Retinoic acid-inducible gene I (RIG-I) is an important regulator of in?uenza virus-induced expression of antiviral cytokines, mainly interferons (IFNs), which are necessary to clear viral infections. In this study, we compared the innate cytokine responses of two mouse CS exposure models following a challenge with influenza A virus (IAV): 1) exposure of the mice to cigarette smoke extract (CSE) intratracheally, and 2) exposure of the mice to CS in a whole-body exposure chamber. Both intratracheal CSE treatment and whole-body CS exposure caused antiviral immunosuppression in these mice, and both CS exposure methods inhibited RIG-I induction. CS attenuated influenza-induced antiviral IFNs and IP-10 expression in vivo. However, we did not find that CS inhibited induction of the proinflammatory cytokines IL-6 and TNF-?, whose expression was induced by IAV. Interestingly, IAV infection also increased toll-like receptor 3 (TLR3) expression in mouse lung, but CS exposure did not impact TLR3 induction in these mice. Together, the results support our previous finding in a human lung organ culture model that the suppression of RIG-I induction and antiviral cytokine responses by CS is likely important in the enhanced susceptibility of smokers to influenza infection in the lung.
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[Mobilization of potassium from soil by ectomycorrhizal fungi].
Wei Sheng Wu Xue Bao
PUBLISHED: 09-26-2014
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Ectomycorrhizal fungi (ECMF), important components in forest ecosystems, could form symbionts with wooden plant roots and participate in nutrient absorption.
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[The influence of the single different radiation dose and time on the microscopic structure and ultrastructure of Balb/c mice].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-25-2014
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To observe the influence of the single different radiation dose and time on the microscopic structure and ultrastructure of Balb/c Mice.
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Gold-catalyzed tandem cycloisomerization/functionalization of in situ generated ?-oxo gold carbenes in water.
J. Org. Chem.
PUBLISHED: 09-25-2014
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A gold-catalyzed tandem cycloisomerization/functionalization of in situ generated ?-oxo gold carbenes in water has been developed, which provides ready access to highly functionalized indole derivatives from o-alkynyl anilines and ynamides. Importantly, gold serves dual catalytic roles to mediate both the cycloisomerization of o-alkynyl anilines and the intermolecular oxidation of ynamides at the same time, thus providing a new type of concurrent tandem catalysis. The use of readily available starting materials, a simple procedure, and mild reaction conditions are other notable features of this method.
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A fast adaptive parameter estimation for total variation image restoration.
IEEE Trans Image Process
PUBLISHED: 09-24-2014
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Estimation of the regularization parameter, which strikes a balance between the data fidelity and regularity, is essential for successfully solving ill-posed image restoration problems. Based on the classical total variation (TV) model and prevalent alternating direction method of multipliers, we hammer out a fast algorithm being able to simultaneously estimate the regularization parameter and restore the degraded image. By applying variable splitting technique to both the regularization term and data fidelity term, we overcome the nondifferentiability of TV and achieve a closed form to update the regularization parameter in each iteration. The solution is guaranteed to satisfy Morozov's discrepancy principle. Furthermore, we present a convergence proof for the proposed algorithm on the premise of a variable regularization parameter. Experimental results demonstrate that the proposed algorithm is superior in speed and competitive in accuracy compared with several state-of-the-art methods. Besides, the proposed method can be smoothly extended to the multichannel image restoration.
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Reelin Induces Branching of Neurons and Radial Glial Cells during Corticogenesis.
Cereb. Cortex
PUBLISHED: 09-24-2014
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Newborn neurons migrate along the processes of radial glial cells (RGCs) to reach their final positions in the cortex. Here, we visualized individual migrating neurons and RGCs using in utero electroporation. We show that branching of migrating neurons and RGCs is closely correlated spatiotemporally with the distribution of Reelin. Time-lapse imaging revealed that the leading processes of migrating neurons gave rise to increasingly more branches once their growth cones contacted the Reelin-containing marginal zone. This was accompanied by translocation of the nucleus and gradual shortening of the leading process. Absence of Reelin in reeler mice altered these processes resulting in misorientation, loss of bipolarity, and aberrant migration of cortical neurons. Moreover, in reeler, the branching of the basal processes of RGCs in the marginal zone was severely disrupted. Consistent with previous reports, we show that in dissociated reeler cortical cultures, exposure to recombinant Reelin enhanced dendritic complexity and glial branching. Our results suggest that Reelin induces branching of the leading processes of migrating neurons and that of basal processes of RGCs when they arrive at the Reelin-containing marginal zone. Branching of these processes may be crucial for the termination of nuclear translocation during the migratory process and for correct neuronal positioning.
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[Clinical characteristics of 104 patients with primary gastrointestinal non-Hodgkin lymphoma].
Zhonghua Xue Ye Xue Za Zhi
PUBLISHED: 09-24-2014
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To analyze the clinical characteristics and prognostic factors in patients with primary gastrointestinal non-Hodgkin lymphoma (PGI-NHL).
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What is Visualize?

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

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

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

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