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Find video protocols related to scientific articles indexed in Pubmed.
A new copper species based on an azo-compound utilized as a homogeneous catalyst for water oxidation.
Dalton Trans
PUBLISHED: 11-11-2014
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A new azo-complex [(L)Cu(II)(NO3)] [L = (E)-3-(pyridin-2-yldiazenyl)naphthalen-2-ol (HL)], was prepared via a one-pot synthetic method at 60 °C and was structurally characterized by IR, EA, PXRD and single crystal X-ray diffraction. In addition, TGA studies indicated that the complex was stable in air. The redox properties were determined by cyclic voltammetry, which revealed that the complex could be utilized as a catalyst for water oxidation under mild conditions. Subsequently, the complex was employed as a catalyst to take part in water oxidation reaction in the presence of a Ce(IV) salt utilized as an oxidant at pH 11 in PBS (Phosphate Buffered Saline) solution. The results suggested that the catalyst exhibited a high stability and activity toward water oxidation reaction under these conditions with an initial TOF of 4.0 kPa h(-1). Calculation methodology was performed to study the mechanism of the reaction, which revealed that in this catalytic process, the initial oxidation of Cu(ii) to Cu(iii) occurred by the formation of an intermediate "Cu(iii)-O-O-Cu(iii)". The formation of this intermediate, resulted in a release of oxygen and closing of the catalytic cycle.
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[Dipylidium caninum infection in an infant: one case report].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 10-28-2014
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This paper reports the diagnosis and therapy of one case of Dipylidium caninum infection in an infant.
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[Clinical significance of ropivacaine local infiltration for postoperative analgesia after total laparoscopic radical gastrectomy in elderly patients].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 10-22-2014
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To explore the analgesic effects and postoperative recovery of ropivacaine incision infiltration in elderly patients after total laparoscopic radical gastrectomy.
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A collagen-based multicellular tumor spheroid model for evaluation of the efficiency of nanoparticle drug delivery.
Artif Cells Nanomed Biotechnol
PUBLISHED: 10-16-2014
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Targeted drug delivery systems, especially those that use nanoparticles, have been the focus of research into cancer therapy during the last decade, to improve the bioavailability and delivery of anticancer drugs to specific tumor sites, thereby reducing the toxicity and side effects to normal tissues. However, the positive antitumor effects of these nanocarriers observed in conventional monolayer cultures frequently fail in vivo, due to the lack of physical and biological barriers resembling those seen in the actual body. Therefore, the collagen-based 3-D multicellular culture system, to screen new nanocarriers for drug delivery and to obtain more adequate and better prediction of therapeutic outcomes in preclinical experiments, was developed. This 3-D culture model was successfully established using optimized density of cells. Our result showed that 3-D cell colonies were successfully developed from 95-D, U87 and HCT116 cell lines respectively, after a seven-day culture in the collagen matrix. The coumarin-conjugated nanoparticles were able to penetrate the matrix gel to reach the tumor cells. The model is supposedly more accurate in reflecting/predicting the dynamics and therapeutic outcomes of candidates for drug transport in vivo, and/or investigation of tumor biology, thus speeding up the pace of discovery of novel drug delivery systems for cancer therapy.
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[Two-micron laser resection of the prostate-tangerine technique for the treatment of large-volume prostate].
Zhonghua Nan Ke Xue
PUBLISHED: 10-14-2014
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To evaluate the clinical efficiency and safety of two-micron laser resection of the prostate-tangerine technique (TmLRP-TT) for the treatment of large-volume ( > 70 ml) prostate in patients with benign prostatic hyperplasia (BPH).
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Merremins A-G, Resin Glycosides from Merremia hederacea with Multidrug Resistance Reversal Activity.
J. Nat. Prod.
PUBLISHED: 10-13-2014
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Five new pentasaccharide resin glycosides, named merremins A-E (1-5), two new pentasaccharide resin glycoside methyl esters, named merremins F and G (6, 7), and four known resin glycosides, murucoidin IV, murucoidin V, stoloniferin IV, and murucoidin XVII, were obtained from the aerial parts of Merremia hederacea. This is the first report of resin glycosides obtained from M. hederacea. In addition, the new compounds can be divided into three types: those possessing an 18-membered ring (1-4), compound 5 with a 20-membered ring, and those with an acyclic core (6, 7). Furthermore, the different types of resin glycosides were evaluated for their multidrug resistance reversal activities. Compounds 1, 5, 6, and murucoidin V were noncytotoxic and enhanced the cytotoxicity of vinblastine by 2.3-142.5-fold at 25 ?M. Compound 5 and murucoidin V, with 20-membered rings, were more active than compound 1, with an 18-membered ring.
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Plasminogen kringle 5 induces endothelial cell apoptosis by triggering a voltage-dependent anion channel 1 (VDAC1) positive feedback loop.
J. Biol. Chem.
PUBLISHED: 10-08-2014
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Human plasminogen kringle 5 (K5) is known to display its potent anti-angiogenesis effect through inducing endothelial cell (EC) apoptosis, and the voltage-dependent anion channel 1 (VDAC1) has been identified as a receptor of K5. However, the exact role and underlying mechanisms of VDAC1 in K5-induced EC apoptosis remain elusive. In the current study, we showed that K5 increased the protein level of VDAC1, which initiated the mitochondrial apoptosis pathway of ECs. Our findings also showed that K5 inhibited the ubiquitin-dependent degradation of VDAC1 by promoting the phosphorylation of VDAC1, possibly at Ser12 and Thr107. The phosphorylated VDAC1 was attenuated by AKT agonist, GSK3? inhibitor and siRNA?suggesting that K5 increased VDAC1 phosphorylation via the AKT-GSK3? pathway. Furthermore, K5 promoted cell surface translocation of VDAC1, and binding between K5 and VDAC1 was observed on the plasma membrane. HKI protein blocked the impact of K5 on the AKT-GSK3? pathway by competitively inhibiting the interaction of K5 and cell surface VDAC1. Moreover, K5-induced EC apoptosis was suppressed by VDAC1 antibody. These data show for the first time that K5-induced EC apoptosis is mediated by the positive feedback loop of "VDAC1-AKT-GSK3?-VDAC1", which may provide new perspectives on the mechanisms of K5-induced apoptosis.
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Scanning tunneling microscopy/spectroscopy of picene thin films formed on Ag(111).
J Chem Phys
PUBLISHED: 09-22-2014
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Using ultrahigh-vacuum low-temperature scanning tunneling microscopy and spectroscopy combined with first principles density functional theory calculations, we have investigated structural and electronic properties of pristine and potassium (K)-deposited picene thin films formed in situ on a Ag(111) substrate. At low coverages, the molecules are uniformly distributed with the long axis aligned along the [112?] direction of the substrate. At higher coverages, ordered structures composed of monolayer molecules are observed, one of which is a monolayer with tilted and flat-lying molecules resembling a (11?0) plane of the bulk crystalline picene. Between the molecules and the substrate, the van der Waals interaction is dominant with negligible hybridization between their electronic states; a conclusion that contrasts with the chemisorption exhibited by pentacene molecules on the same substrate. We also observed a monolayer picene thin film in which all molecules were standing to form an intermolecular ? stacking. Two-dimensional delocalized electronic states are found on the K-deposited ? stacking structure.
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[Impacts on analgesia and detumescence in ankle sprain treated with acupuncture at Xiaojie point combined with tendon-regulation manipulation].
Zhongguo Zhen Jiu
PUBLISHED: 09-20-2014
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To compare the efficacy difference of analgesia and detumescence on ankle sprain among acupuncture at Xiaojie point combined with tendon regulation manipulation, acupuncture at Xiaojie point and tendon regulation manipulation.
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The alteration of Hippo/YAP signaling in the development of hypertrophic cardiomyopathy.
Basic Res. Cardiol.
PUBLISHED: 08-29-2014
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Hypertrophic cardiomyopathy (HCM) is a leading cause of heart failure and sudden death in adolescents and young adults. Recently, the role of the Hippo/YAP pathway has been investigated in the pathogenesis of HCM, although the detailed molecular mechanisms largely remain elusive. In this study, we demonstrated an up-regulation of YAP mRNA and protein levels in both HCM patient samples and transverse aortic constriction murine models as well as reduced phosphorylation of YAP at serine 127 accompanied by increased transcription of YAP-mediated genes in hypertrophic heart tissues. The cardiomyocyte-specific transgene of human YAP induced cardiac hypertrophy and increased fetal gene expression in the heart. In primary cultured murine cardiomyocytes, ectopic expression of YAP resulted in increased cellular size, whereas the knockdown of YAP reduced the cell size induced by phenylephrine treatment. Interestingly, both mRNA and protein levels of MST1, the kinase upstream of YAP, were dramatically decreased. Further experiments showed that transcription factor FOXO3 binds to the MST1 promoter and that the PI3 K/Akt/FOXO3 signaling pathway regulates MST1 expression. Our findings define the alteration of the Hippo/YAP pathway in the development of HCM. The exploitation of this pathway may provide a novel therapeutic avenue for this disease.
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Anion-Directed Self-Assembly of Two Half-Sandwich Ruthenium-Based Metallamacrocycles as Catalysts for Water Oxidation.
Chem Asian J
PUBLISHED: 08-19-2014
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The binuclear [?(6) -(cymene)Ru(L)]2 (OTf)2 (TfO(-) =trifluoromethanesulfonate) and tetranuclear [?(6) -(cymene)Ru(L)]4 (NO3 )4 metallacycles were prepared by treating the pyridyl-substituted 8-hydroxyquinoline ligand (E)-2-[2-(pyridin-3-yl)vinyl]quinolin-8-ol (HL) with [(p-cymene)Ru(?-Cl)Cl]2 in the presence of AgOTf or AgNO3 . The molecular structures of these complexes were confirmed by single-crystal X-ray diffraction, which revealed that both complexes have macrocycle frameworks induced by the TfO(-) and NO3 (-) counteranions, respectively. The electrochemical properties of the two metallacycles were investigated by cyclic voltammetry, which showed that they have great potential as catalysts for water oxidation. Good efficiency was obtained by utilizing the nitrate complex as a water oxidation catalyst in the presence of a Ce(IV) salt as an oxidant at high pH values.
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Enhanced contrast separation in scanning electron microscopes via a suspended-thin sample approach.
Ultramicroscopy
PUBLISHED: 07-30-2014
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A suspended-thin-sample (STS) approach for signal selection and contrast separation is developed in scanning electron microscopes with commonly used primary beam energies and traditional detectors. Topography contrast, electron channeling contrast and composition contrast are separated and largely enhanced from suspended thin samples of several hundred nanometers in thickness, which is less than the escape depth of backscattered electrons. This imaging technique enables to detect relatively pure secondary electron and elastic backscattered electron singles, whereas suppress multiple inelastic scattering effects. The provided contrast features are different from those of bulk samples, which are largely mixed with inelastic scattering effects. The STS imaging concept and method could be expected to have more applications in distinguishing materials of nanostructures, multilayers, compounds and composites, as well as in SEM-based electron backscatter diffraction, cathodoluminesence, and x-ray microanalysis.
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Flexible organic light-emitting diodes with enhanced light out-coupling efficiency fabricated on a double-sided nanotextured substrate.
ACS Appl Mater Interfaces
PUBLISHED: 06-20-2014
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High-efficiency organic light-emitting diodes (OLEDs) have generated tremendous research interest. One of the exciting possibilities of OLEDs is the use of flexible plastic substrates, which unfortunately have a mismatching refractive index compared with the conventional ITO anode and the air. To unlock the light loss on flexible plastic, we report a high-efficiency flexible OLED directly fabricated on a double-sided nanotextured polycarbonate substrate by thermal nanoimprint lithography. The template for the nanoimprint process is a replicate from a silica arrayed with nanopillars and fabricated by ICP etching through a SiO2 colloidal spheres mask. It has been shown that with the internal quasi-periodical scattering gratings the efficiency enhancement can reach 50% for a green light OLED, and with an external antireflection structure, the normal transmittance is increased from 89% to 94% for paraboloid-like pillars. The OLED directly fabricated on the double-sided nanotextured polycarbonate substrate has reached an enhancing factor of ?2.8 for the current efficiency.
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High-efficiency, broad-band and wide-angle optical absorption in ultra-thin organic photovoltaic devices.
Opt Express
PUBLISHED: 06-13-2014
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Metal nanogratings as one of the promising architectures for effective light trapping in organic photovoltaics (OPVs) have been actively studied over the past decade. Here we designed a novel metal nanowall grating with ultra-small period and ultra-high aspect-ratio as the back electrode of the OPV device. Such grating results in the strong hot spot effect in-between the neighboring nanowalls and the localized surface plasmon effect at the corners of nanowalls. These combined effects make the integrated absorption efficiency of light over the wavelength range from 400 to 650 nm in the active layer for the proposed structure, with respect to the equivalent planar structure, increases by 102% at TM polarization and by 36.5% at the TM/TE hybrid polarization, respectively. Moreover, it is noted that the hot spot effect in the proposed structure is more effective for ultra-thin active layers, which is very favorable for the exciton dissociation and charge collection. Therefore such a nanowall grating is expected to improve the overall performance of OPV devices.
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The sheep genome illuminates biology of the rumen and lipid metabolism.
Science
PUBLISHED: 06-07-2014
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Sheep (Ovis aries) are a major source of meat, milk, and fiber in the form of wool and represent a distinct class of animals that have a specialized digestive organ, the rumen, that carries out the initial digestion of plant material. We have developed and analyzed a high-quality reference sheep genome and transcriptomes from 40 different tissues. We identified highly expressed genes encoding keratin cross-linking proteins associated with rumen evolution. We also identified genes involved in lipid metabolism that had been amplified and/or had altered tissue expression patterns. This may be in response to changes in the barrier lipids of the skin, an interaction between lipid metabolism and wool synthesis, and an increased role of volatile fatty acids in ruminants compared with nonruminant animals.
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Estimating Young's modulus of graphene with Raman scattering enhanced by micrometer tip.
Nanotechnology
PUBLISHED: 06-04-2014
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We demonstrate that the Raman intensities of G and 2D bands of a suspended graphene can be enhanced using a gold tip with an apex size of 2.3 ?m. The enhancement decays with the tip-graphene distance exponentially and remains detectable at a distance of 1.5 ?m. Raman mappings show that the enhanced area is comparable to the apex size. Application of a bias voltage to the tip can attract the graphene so that Raman signals are intensified. The exponential enhancement-distance relationship enables the measurement of the graphene deformation, and the Young's modulus of graphene is estimated to be 1.48 TPa.
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Prognostic effect of p53 expression in patients with completely resected colorectal cancer.
Tumour Biol.
PUBLISHED: 05-25-2014
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The p53 protein is closely involved in the carcinogenesis of many kinds of cancers. Though the prognostic role of p53 expression for the survival of colorectal cancer (CRC) patients has been preliminarily identified, the prognostic effect of p53 expression in patients with completely resected CRC is still unclear. Therefore, a retrospective cohort study was performed to assess the prognostic role of p53 expression for overall survival in patients with completely resected CRC. A total of 153 patients (mean age 50.9 years) with completely resected CRC was finally included in the retrospective cohort study. Kaplan-Meier product-limit methods and log-rank test were used to estimate overall survival distribution and test the difference. In addition, multivariable analysis by Cox regression model was also used to test the prognostic role of p53 expression on overall survival by adjusting for other confounding factors. Of those 153 CRC patients, 62 (40.5 %) were positive for p53 protein expression in the tumor tissues. The log-rank test showed that there was an obvious difference in the overall survival between the p53-positive group and the p53-negative group (P?
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Effect of fluoride content on ion release from cast and selective laser melting-processed Co-Cr-Mo alloys.
J Prosthet Dent
PUBLISHED: 05-21-2014
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Selective laser melting (SLM) alloy is gaining popularity in prosthetic dentistry. However, its biocompatibility has been of some concern because of long-term exposure to fluoride in the oral environment.
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The marginal fit of selective laser melting-fabricated metal crowns: An in vitro study.
J Prosthet Dent
PUBLISHED: 05-20-2014
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The selective laser melting technique is attracting interest in prosthetic dentistry. The marginal fit is a key criterion for fixed restorations.
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Water oxidation catalysts and pH sensors based on azo-conjugated iridium/rhodium motifs.
Dalton Trans
PUBLISHED: 05-16-2014
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Herein we report the molecular structures and electronic properties of ionic, hydrophobic half-sandwich complexes with formula [?(5)-Cp*Ir(L)(Cl)](OTf) (), [?(5)-Cp*Rh(L)(Cl)](OTf) (), [?(5)-Cp*Ir(L)(H2O)](OTf)2 () and [?(5)-Cp*Rh(L)(H2O)](OTf)2 (), where L is 1-(2-pyridylazo)-2-naphthol. The electrochemical properties of these complexes have been investigated, and they displayed good electronic properties for use as water oxidation catalysts. Interestingly, the color of their solutions is unambiguously transformed from brown to green at pH = 12; the color changes of , and are especially apparent. For this reason, their use as pH sensors for detecting solution pH values can be explored.
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[Research on the temperature field detection method of hot forging based on long-wavelength infrared spectrum].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 05-15-2014
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A temperature field detection method based on long-wavelength infrared spectrum for hot forging is proposed in the present paper. This method combines primary spectrum pyrometry and three-stage FP-cavity LCTF. By optimizing the solutions of three group nonlinear equations in the mathematical model of temperature detection, the errors are reduced, thus measuring results will be more objective and accurate. Then the system of three-stage FP-cavity LCTF was designed on the principle of crystal birefringence. The system realized rapid selection of any wavelength in a certain wavelength range. It makes the response of the temperature measuring system rapid and accurate. As a result, without the emissivity of hot forging, the method can acquire exact information of temperature field and effectively suppress the background light radiation around the hot forging and ambient light that impact the temperature detection accuracy. Finally, the results of MATLAB showed that the infrared spectroscopy through the three-stage FP-cavity LCTF could meet the requirements of design. And experiments verified the feasibility of temperature measuring method. Compared with traditional single-band thermal infrared imager, the accuracy of measuring result was improved.
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Lysophosphatidic acid acts as a nutrient-derived developmental cue to regulate early hematopoiesis.
EMBO J.
PUBLISHED: 05-14-2014
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Primitive hematopoiesis occurs in the yolk sac blood islands during vertebrate embryogenesis, where abundant phosphatidylcholines (PC) are available as important nutrients for the developing embryo. However, whether these phospholipids also generate developmental cues to promote hematopoiesis is largely unknown. Here, we show that lysophosphatidic acid (LPA), a signaling molecule derived from PC, regulated hemangioblast formation and primitive hematopoiesis. Pharmacological and genetic blockage of LPA receptor 1 (LPAR1) or autotoxin (ATX), a secretory lysophospholipase that catalyzes LPA production, inhibited hematopoietic differentiation of mouse embryonic stem cells and impaired the formation of hemangioblasts. Mechanistic experiments revealed that the regulatory effect of ATX-LPA signaling was mediated by PI3K/Akt-Smad pathway. Furthermore, during in vivo embryogenesis in zebrafish, LPA functioned as a developmental cue for hemangioblast formation and primitive hematopoiesis. Taken together, we identified LPA as an important nutrient-derived developmental cue for primitive hematopoiesis as well as a novel mechanism of hemangioblast regulation.
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Localized retinal nerve fiber layer defects and stroke.
Stroke
PUBLISHED: 04-15-2014
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Because the blood circulation system of retina and brain are closely related to each other, we examined whether stroke is associated with localized retinal nerve fiber layer defects (RNFLDs).
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Uniaxial movements of a metal-cyanide framework switched by weak interactions through dehydration and rehydration.
Chemistry
PUBLISHED: 04-01-2014
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A metal-cyanide framework undergoes a dehydration-rehydration triggered reversible single-crystal-to-single-crystal transformation. The resulting accordion-like contraction-expansion corresponds to a size change along the c axis as much as 24?%. This anisotropic response arises from the cooperativity among the water molecules, K ions, and CN groups between the unique two-dimensional bimetallic layers through weak interactions of hydrogen bonds and electrostatic (ionic) interactions. The key role of the water molecules in the dehydration-rehydration process is revealed by solid-state (1)H?NMR spectroscopy and dielectric measurements.
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Bandgap engineering and manipulating electronic and optical properties of ZnO nanowires by uniaxial strain.
Nanoscale
PUBLISHED: 03-29-2014
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Bandgap engineering is a common practice for tuning semiconductors for desired physical properties. Although possible strain effects in semiconductors have been investigated for over a half-century, a profound understanding of their influence on energy bands, especially for large elastic strain remains unclear. In this study, a systematic investigation of the transport properties of n-type [0001] ZnO nanowires was performed at room temperature using the in situ scanning tunnelling microscope-transmission electron microscope technique which shows that the transport properties vary with the applied external uniaxial strain. It has been found that the resistance of ZnO nanowires decreases continuously with increasing compressive strain, but increases under increased tensile strain, suggesting piezo-resistive characteristics. A series of near-band-edge emissions were measured and the corresponding variations of bandgaps were obtained during the application of tensile strain of individual ZnO nanowires via cathodoluminescence spectroscopy. From this, a relationship between the changes of energy bandgap and the transport properties, both induced by uniaxial strain, is built.
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Variation of exciton emissions of ZnO whiskers reversibly tuned by axial tensile strain.
Opt Express
PUBLISHED: 03-26-2014
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Applying strain on semiconductors is a powerful method to modulate its electronic structures and optical properties. In this study, the behavior of liquid-nitrogen exciton emissions and the longitudinal optical phonon-exciton interactions of tensile strained [0001]-orientated ZnO whiskers were investigated using in situ cathodoluminescence spectroscopy. It has been found that, under the axial tensile strain, various exciton emissions shift to the long wavelength and their shifts have a linear relationship with the applied strain. This linear relationship and reversible shift suggest that the strain plays a dominating role in manipulating light emissions of axially strained ZnO whiskers.
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A comparison of corrosion resistance of cobalt-chromium-molybdenum metal ceramic alloy fabricated with selective laser melting and traditional processing.
J Prosthet Dent
PUBLISHED: 03-17-2014
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A cobalt-chromium-molybdenum alloy fabricated by selective laser melting is a promising material; however, there are concerns about the change in its corrosion behavior.
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Retinal vessel diameter and estimated cerebrospinal fluid pressure in arterial hypertension: the Beijing Eye Study.
Am. J. Hypertens.
PUBLISHED: 03-15-2014
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Hypertensive retinal microvascular abnormalities include an increased retinal vein-to-artery diameter ratio. Because central retinal vein pressure depends on cerebrospinal fluid pressure (CSFP), we examined whether the retinal vein-to-artery diameter ratio and other retinal hypertensive signs are associated with CSFP.
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Azo-conjugated half-sandwich Rh/Ru complexes for homogeneous water-oxidation catalysis.
Dalton Trans
PUBLISHED: 03-15-2014
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Herein we report the molecular structures and electronic properties of ionic, hydrophobic, half-sandwich complexes of the formula [?(5)-Cp*Rh(L)(MeOH)] (1) and [?(6)-CyRu(L)(H2O)] (2), where L is azo-dye compound of (p-(2-hydroxy-1-naphthylazo)benzenesulfonic acid sodium salt). Both these complexes have been investigated electrochemically and found to display good electronic properties for use as water-oxidation catalysts potentially.
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Solid pseudopapillary tumor of the pancreas with liver metastasis: Clinical features and management.
Eur J Surg Oncol
PUBLISHED: 03-13-2014
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To summarize the diagnosis and management of metastatic pancreatic solid pseudopapillary tumors (SPTs).
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Recent studies of 5-fluorouracil resistance in pancreatic cancer.
World J. Gastroenterol.
PUBLISHED: 02-19-2014
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Resistance to 5-fluorouracil (5-FU), an important anticancer drug, is a serious challenge in the treatment of pancreatic cancer. Equilibrative nucleoside transporter 1 and multidrug-resistance protein (MRP) 5 and MRP8, rather than P-glycoprotein, play important roles in 5-FU transport. Thymidylate synthase, dihydropyrimidine dehydrogenase, methylenetetrahydrofolate reductase and thymidine phosphorylase are four key enzymes involved in 5-FU metabolism. Other metabolic enzymes, including uridine monophosphate synthetase, also contribute to chemoresistance. Intracellular signaling pathways are an integrated network, and nuclear factor kappa-light-chain-enhancer of activated B cells, AKT and extracellular signal-regulated kinases are signaling pathways that are particularly relevant to 5-FU resistance. In addition, recent reports indicate that STAT-3 is a crucial survival protein. Proteomic assays provide a powerful tool for identifying target proteins and understanding the role of microRNAs and stromal factors to facilitate the development of strategies to combat 5-FU resistance.
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Comparison of hand-sewn and stapled anastomoses in surgeries of gastrointestinal tumors based on clinical practice of China.
World J Surg Oncol
PUBLISHED: 02-18-2014
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There is a lack of studies comparing stapled suturing and hand-sewn suturing in the surgeries of gastrointestinal tumors based on the clinical practice of Chinese surgeons.
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Self-assembled quantum dot structures in a hexagonal nanowire for quantum photonics.
Adv. Mater. Weinheim
PUBLISHED: 02-14-2014
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Two types of quantum nanostructures based on self-assembled GaAs quantumdots embedded into GaAs/AlGaAs hexagonal nanowire systems are reported, opening a new avenue to the fabrication of highly efficient single-photon sources, as well as the design of novel quantum optics experiments and robust quantum optoelectronic devices operating at higher temperature, which are required for practical quantum photonics applications.
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Iridium-mediated regioselective B-H/C-H activation of carborane cage: a facile synthetic route to metallacycles with a carborane backbone.
J. Am. Chem. Soc.
PUBLISHED: 02-07-2014
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One-pot reactions of carborane carboxylic acids (L), [Cp*IrCl2]2, and silver salt are reported, which lead to regioselective B-H or C-H bond activation at ambient temperature in good yields. This process is demonstrated for three carborane (o-, m-, p-) dicarboxylates, and metal-mediated B-H functionalization of a p-carborane derivative is accomplished for the first time. Two metal-induced self-assembly routes to tetra-nuclear metallacycles 3 and 5 were performed through B(4, 7)/H and B(2, 10)/H activation, respectively, and the two metallacycles were found to be stable and to exist in solution as discrete complexes. Different activation modes in the carborane cage were ascribed to the characteristic structure of the products and the electronic density differences. The analogous reaction of o-carborane monocarboxylate with the same metal precursor gave the C-H activation complex 6, indicating that the B-H bond is more stable than the C-H bond in this carborane cage. The selective activation was confirmed by DFT calculation results. In this study, a facile and efficient synthetic route has been developed through specific B-H bond activation to construct carborane-based metallacycles that are unavailable by conventional methods.
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Self-assembly of single "square" quantum rings in gold-free GaAs nanowires.
Nanoscale
PUBLISHED: 02-05-2014
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Single nanostructures embedded within nanowires (NWs) represent one of the most promising technologies for applications in quantum photonics. However, fabrication imperfections and etching-induced defects are inevitable for top-down fabrications, whereas self-assembly bottom-up approaches cannot avoid the difficulties of its stochastic nature and are limited to restricted heterogeneous material systems. Here we demonstrate the versatile self-assembly of single "square" quantum rings (QR) on the sidewalls of gold-free GaAs NWs for the first time. By tuning the deposition temperature, As overpressure and amount of gallium-droplets, we were able to control the density and morphology of the structure, yielding novel single quantum dots, QR, coupled QRs, and nano-antidots. A proposed model based on a strain-driven, transport-dependent nucleation of gallium droplets at high temperature accounts for the formation mechanism of these structures. We achieved a single-QR-in-NW structure, of which the optical properties were analyzed using micro-photoluminescence at 10 K and a spatially resolved cathodoluminescence technique at 77 K. The spectra show sharp discrete peaks; of these peaks, the narrowest linewidth (separation) was 578 ?eV (1-3 meV), reflecting the quantized nature of the ring-type electronic states.
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A direct and polymer-free method for transferring graphene grown by chemical vapor deposition to any substrate.
ACS Nano
PUBLISHED: 01-31-2014
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We demonstrate a polymer-free method that can routinely transfer relatively large-area graphene to any substrate with advanced electrical properties and superior atomic and chemical structures as compared to the graphene sheets transferred with conventional polymer-assisted methods. The graphene films that are transferred with polymer-free method show high electrical conductance and excellent optical transmittance. Raman spectroscopy and X-ray/ultraviolet photoelectron spectroscopy also confirm the presence of high quality graphene sheets with little contamination after transfer. Atom-resolved images can be obtained using scanning tunneling microscope on as-transferred graphene sheets without additional cleaning process. The mobility of the polymer-free graphene monolayer is as high as 63,000 cm(2) V(-1) s(-1), which is 50% higher than the similar sample transferred with the conventional method. More importantly, this method allows us to place graphene directly on top of devices made of soft materials, such as organic and polymeric thin films, which widens the applications of graphene in soft electronics.
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Visual acuity and subfoveal choroidal thickness: the Beijing Eye Study.
Am. J. Ophthalmol.
PUBLISHED: 01-30-2014
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To examine the association between best corrected visual acuity (BCVA) and subfoveal choroidal thickness.
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Subfoveal choroidal thickness and cerebrospinal fluid pressure: the Beijing Eye Study 2011.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 01-30-2014
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The venous choroidal blood drains through the superior orbital vein into the intracranial cavernous sinus. The cerebrospinal fluid pressure (CSFP) may thus influence the choroidal venous blood pressure. Since volume and thickness of the choroid depend on its pressure, we tested the hypothesis whether the subfoveal choroidal thickness (SFCT) is associated with CSFP.
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Activation of vascular endothelial growth factor receptor-3 in macrophages restrains TLR4-NF-?B signaling and protects against endotoxin shock.
Immunity
PUBLISHED: 01-27-2014
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Toll-like receptors (TLRs) are critical in mediating innate immune responses against infections. However, uncontrolled TLR-triggered inflammation is associated with endotoxin shock. To better understand the homeostatic mechanisms induced by TLR4 signaling, we screened a group of key cytokines, chemokines, growth factors, and their receptors for bacteria- or LPS-induced expression. The surface vascular endothelial growth factor receptor-3 (VEGFR-3) and its ligand VEGF-C were upregulated in macrophages. VEGFR-3 ligation by VEGF-C significantly attenuated proinflammatory cytokine production. Notably, ablation of the ligand-binding domain or tyrosine kinase activity of VEGFR-3 rendered mice more sensitive to septic shock. VEGFR-3 restrained TLR4-NF-?B activation by regulating the PI3-kinase-Akt signaling pathway and SOCS1 expression. Aside from targeting lymphatic vessels, we suggest a key role of VEGFR-3 on macrophages to prevent infections that is complicated with lymphoedema. Thus, VEGFR-3-VEGF-C signaling represents a "self-control" mechanism during antibacterial innate immunity.
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Deficiency of slow skeletal muscle troponin T causes atrophy of type I slow fibres and decreases tolerance to fatigue.
J. Physiol. (Lond.)
PUBLISHED: 01-20-2014
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The total loss of slow skeletal muscle troponin T (ssTnT encoded by TNNT1 gene) due to a nonsense mutation in codon Glu(180) causes a lethal form of recessively inherited nemaline myopathy (Amish nemaline myopathy, ANM). To investigate the pathogenesis and muscle pathophysiology of ANM, we studied the phenotypes of partial and total loss of ssTnT in Tnnt1 gene targeted mice. An insertion of neomycin resistance cassette in intron 10 of Tnnt1 gene caused an approximately 60% decrease in ssTnT protein expression whereas cre-loxP-mediated deletion of exons 11-13 resulted in total loss of ssTnT, as seen in ANM muscles. In diaphragm and soleus muscles of the knockdown and knockout mouse models, we demonstrated that ssTnT deficiency resulted in significantly decreased levels of other slow fibre-specific myofilament proteins whereas fast fibre-specific myofilament proteins were increased correspondingly. Immunohistochemical studies revealed that ssTnT deficiency produced significantly smaller type I slow fibres and compensatory growth of type II fast fibres. Along with the slow fibre atrophy and the changes in myofilament protein isoform contents, ssTnT deficiency significantly reduced the tolerance to fatigue in soleus muscle. ssTnT-deficient soleus muscle also contains significant numbers of small-sized central nuclei type I fibres, indicating active regeneration. The data provide strong support for the essential role of ssTnT in skeletal muscle function and the causal effect of its loss in the pathology of ANM. This observation further supports the hypothesis that the function of slow fibres can be restored in ANM patients if a therapeutic supplement of ssTnT is achieved.
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Phosphodiesterase types 3 and 4 regulate the phasic contraction of neonatal rat bladder smooth myocytes via distinct mechanisms.
Cell. Signal.
PUBLISHED: 01-06-2014
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Activation of the cyclic AMP (cAMP) pathway reduces bladder contractility. However, the role of phosphodiesterase (PDE) families in regulating this function is poorly understood. Here, we compared the contractile function of the cAMP hydrolyzing PDEs in neonatal rat bladder smooth myocytes. RT-PCR and Western blotting analysis revealed that several isoforms of PDE1-4 were expressed in neonatal rat bladder. While 8-methoxymethyl-3-isobutyl-1-methylxanthine (a PDE1 inhibitor) and BAY-60-7550 (a PDE2 inhibitor) had no effect on the carbachol-enhanced phasic contractions of bladder strips, cilostamide (Cil, a PDE3 inhibitor) and Ro-20-1724 (Ro, a PDE4 inhibitor) significantly reduced these contractions. This inhibitory effect of Ro was blunted by the PKA inhibitor H-89, while the inhibitory effect of Cil was strongly attenuated by the PKG inhibitor KT 5823. Application of Ro in single bladder smooth myocytes resulted in an increase in Ca(2+) spark frequency but a decrease both in Ca(2+) transients and in sarcoplasmic reticulum (SR) Ca(2+) content. In contrast, Cil had no effect on these events. Furthermore, Ro-induced inhibition of the phasic contractions was significantly blocked by ryanodine and iberiotoxin. Taken together, PDE3 and PDE4 are the main PDE isoforms in maintaining the phasic contractions of bladder smooth myocytes, with PDE4 being functionally more active than PDE3. However, their roles are mediated through different mechanisms.
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Overcoming multidrug resistance in 2D and 3D culture models by controlled drug chitosan-graft poly(caprolactone)-based nanoparticles.
J Pharm Sci
PUBLISHED: 01-03-2014
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The principal limitations of chemotherapy are dose-limiting systemic toxicity and the development of multidrug-resistant phenotypes. The aim of this study was to investigate the efficiency of a new sustained drug delivery system based on chitosan and ?-caprolactone to overcome multidrug resistance in monolayer and drug resistance associated with the three-dimensional (3D) tumor microenvironment in our established 3D models. The 5-fluorouracil (5-FU)-loaded nanoparticles (NPs) were characterized by transmission electron microscope and dynamic light scattering, and its released property was determined at different pH values. 5-FU/NPs exhibited well-sustained release properties and markedly enhanced the cytotoxicity of 5-FU against HCT116/L-OHP or HCT8/VCR MDR cells in two-dimensional (2D) and its parental cells in 3D collagen gel culture with twofold to threefold decrease in the IC50 values, as demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Hoechst/propidium iodide staining and flow cytometry analysis. Furthermore, the possible mechanism was explored by high-performance liquid chromatography and rhodamine 123 accumulation experiment. Overall, the results demonstrated that 5-FU/NPs increase intracellular concentration of 5-FU and enhance its anticancer efficiency by inducing apoptosis. It was suggested that this novel NPs are a promising carrier to decrease toxic of 5-FU and has the potential to reverse the forms of both intrinsic and acquired drug resistance in 2D and 3D cultures.
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MicroRNA-34a negatively regulates anesthesia-induced hippocampal apoptosis and memory impairment through FGFR1.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Mounting evidence has shown the toxic effects of anesthesia to neonatal hippocampus. We used an in vivo mouse model to explore the role of microRNA 34a (miR-34a) in regulating anesthesia-induced hippocampal neurotoxicity.
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Ten-year cumulative incidence of diabetic retinopathy. The beijing eye study 2001/2011.
PLoS ONE
PUBLISHED: 01-01-2014
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To assess the cumulative 10-year incidence of diabetic retinopathy (DR) and its associated factors in a population living in Greater Beijing.
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The electronic structure and optical properties of Mn and B, C, N co-doped MoS2 monolayers.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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The electronic structure and optical properties of Mn and B, C, N co-doped molybdenum disulfide (MoS2) monolayers have been investigated through first-principles calculations. It is shown that the MoS2 monolayer reflects magnetism with a magnetic moment of 0.87 ?B when co-doped with Mn-C. However, the systems co-doped with Mn-B and Mn-N atoms exhibit semiconducting behavior and their energy bandgaps are 1.03 and 0.81 eV, respectively. The bandgaps of the co-doped systems are smaller than those of the corresponding pristine forms, due to effective charge compensation between Mn and B (N) atoms. The optical properties of Mn-B (C, N) co-doped systems all reflect the redshift phenomenon. The absorption edge of the pure molybdenum disulfide monolayer is 0.8 eV, while the absorption edges of the Mn-B, Mn-C, and Mn-N co-doped systems become 0.45, 0.5, and 0 eV, respectively. As a potential material, MoS2 is widely used in many fields such as the production of optoelectronic devices, military devices, and civil devices.
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Oncogenic GNAQ and GNA11 mutations in uveal melanoma in Chinese.
PLoS ONE
PUBLISHED: 01-01-2014
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To examine whether GNAQ and GNA11 somatic mutations previously identified in uveal melanomas of Caucasians are associated with uveal melanomas in Chinese patients.
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Subfoveal choroidal thickness and glaucoma. The Beijing Eye Study 2011.
PLoS ONE
PUBLISHED: 01-01-2014
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To examine subfoveal choroidal thickness (SFCT) in eyes with glaucoma, using enhanced depth imaging spectral domain optical coherence tomography.
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A novel cysteine-sparing NOTCH3 mutation in a Chinese family with CADASIL.
PLoS ONE
PUBLISHED: 01-01-2014
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Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an adult onset cerebral small vessel disorder caused by the mutations of the neurogenic locus notch homolog protein 3 (NOTCH3) gene. The extracellular part of NOTCH3 is composed of 34 epidermal growth factor-like (EGF-like) repeat domains. Each EGF-like domain is rich of cysteine and glycine to produce three loops that are essential for high-affinity binding to its ligand. Nearly all reported CADASIL-associated mutations result in gain or loss of a cysteine residue within the EGF-like domains. Only a few cysteine-sparing NOTCH3 mutations have been documented in the patients with CADASIL to date. Here, we reported a Chinese CADASIL family with a cysteine-sparing NOTCH3 mutation. In this family, affected patients had dizziness, memory loss, gait instability, or hemiplegia. Brain magnetic resonance imaging (MRI) showed diffuse leukoencephalopathy with confluent signal abnormalities in the periventricular white matter, basal ganglia, and centrum semiovale bilaterally. By screening the entire coding region of NOTCH3, a novel missense mutation p.G149V (c.446G>T) was found. This mutation was not detected in 400 normal controls. Considering the critical position of glycine within the C-loop of EGF-like domain and its high conservation through evolution, p.G149V mutation could be a potential pathogenic cause for CADASIL.
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[Prevalence and causes of blindness and moderate and severe visual impairment among adults aged 50 years or above in Changji City of Xinjiang Uygur Autonomous Region: the China Nine-Province survey].
Zhonghua Yan Ke Za Zhi
PUBLISHED: 12-17-2013
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To investigate the prevalence and causes of blindness and moderate and severe visual impairment among adults aged ? 50 years in Changji City of Xinjiang Uygur Autonomous Region, China.
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[Discussion on barium sulfate turbidity as arbitration inspection method for sulfate in drinking water].
Wei Sheng Yan Jiu
PUBLISHED: 11-14-2013
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To evaluate the suitability of barium sulfate turbidity in Standard examination methods for drinking water (GB/T 5750.5-2006) as arbitration inspection method of sulfate in drinking water by evaluation of uncertainty.
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GYY4137, a novel hydrogen sulfide-releasing molecule, likely protects against high glucose-induced cytotoxicity by activation of the AMPK/mTOR signal pathway in H9c2 cells.
Mol. Cell. Biochem.
PUBLISHED: 09-26-2013
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Diabetic cardiomyopathy (DCM) has become a major cause of diabetes-related morbidity and mortality. Increasing evidences have proved that hydrogen sulfide (H2S) fulfills a positive role in regulating diabetic myocardial injury. The present study was designed to determine whether GYY4137, a novel H2S-releasing molecule, protected H9c2 cells against high glucose (HG)-induced cytotoxicity by activation of the AMPK/mTOR signal pathway. H9c2 cells were incubated in normal glucose (5.5 mM), 22, 33, and 44 mM glucose for 24 h to mimic the hyperglycemia in DCM in vitro. Then we added 50, 100, and 200 ?M GYY4137, and measured the cell viability, lactate dehydrogenase (LDH) enzyme activity, and mitochondrial membrane potential (MMP). 0.5 mM 5-amino-4-imidazole-carboxamide riboside (AICAR, an AMPK activator) and 1 mM adenine 9-?-D-arabinofuranoside (Ara-A, an AMPK inhibitor) were used to identity whether the AMPK/mTOR signal pathway was involved in GYY4137-mediated cardioprotection. We demonstrated that HG decreased cell viability and increased LDH enzyme activity in a concentration-dependent manner. 33 mM HG treatment for 24 h was chosen as our model group for further study. Both 100 and 200 ?M GYY4137 treatments significantly attenuated HG-induced cell viability decrement, LDH enzyme activity increase, and MMP collapse. AICAR had similar effects to GYY4137 treatment while Ara-A attenuated GYY4137-mediated cardioprotection. Importantly, both GYY4137 and AICAR increased AMPK phosphorylation and decreased mTOR phosphorylation compared with the HG model group while Ara-A attenuated GYY4137-mediated AMPK phosphorylation increase and mTOR phosphorylation decrement. In conclusion, we propose that GYY4137 likely protects against HG-induced cytotoxicity by activation of the AMPK/mTOR signal pathway in H9c2 cells.
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Two-micrometer thulium laser resection of the prostate-tangerine technique for patients with acute urinary retention.
Lasers Med Sci
PUBLISHED: 09-02-2013
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Two-micrometer thulium laser resection of the prostate-tangerine technique (TmLRP-TT) has been introduced as a minimally invasive treatment for benign prostatic hyperplasia (BPH). Acute urinary retention (AUR) is a common and serious complication of BPH. The study was undertaken to assess the clinical efficacy and safety of TmLRP-TT in the treatment of patients with AUR secondary to BPH. A prospective evaluation of 52 patients undergoing TmLRP-TT from December 2011 to November 2012 was carried out. Preoperative status, surgical details, and perioperative complications were recorded. The follow-up outcome was evaluated with subjective and objective tests at 1 and 6 months. Mean age was 70.3?±?7.8 years old. Mean prostate volume was 69.6?±?31.6 ml, and mean residual volume with retention was 274.5?±?150.7 ml. Mean operative time was 64.1?±?30.4 min. Mean catheterization duration was 5.4?±?1.1 days. The mean International Prostate Symptom Score, quality of life score, and postvoid residual urine volume decreased significantly at 6-month follow-up (21.6?±?6.8 vs. 6.8?±?3.2, 4.4?±?1.2 vs. 0.9?±?0.8, 274.5?±?150.7 vs. 40.6?±?22.5 ml). The mean maximum urinary flow rate was 18.7?±?6.9 ml/s postoperative. Two (3.8 %) of the patients required blood transfusion in operation. Five (9.6 %) of the patients had transient hematuria postoperative, and two (3.8 %) of them received 3 days recatheterization due to clot retention. The early clinical results suggest that the TmLRP-TT is a promising safe, effective, and minimally invasive treatment for patients with AUR secondary to BPH. The incidence of complications was low.
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Baicalein inhibits DMBA/TPA-induced skin tumorigenesis in mice by modulating proliferation, apoptosis, and inflammation.
Inflammation
PUBLISHED: 08-24-2013
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Baicalein, one of the four major flavanoids extracted from the root of Scutellaria baicalensis, has been shown to exert chemopreventive effect against several cancers, including skin cancer. However, the precise mechanisms remain to be elucidated. In the present study, we investigated the chemopreventive activity of baicalein against 7,12-dimethylbenz[a]anthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA)-mediated skin tumorigenesis in C57BL/6 mice. We found that topical treatment with baicalein resulted in a significant inhibitory effect on DMBA/TPA-mediated tumor promotion. Furthermore, we observed that baicalein suppressed cell proliferation and promoted apoptosis in DMBA/TPA-mediated group. Additionally, pretreatment with baicalein inhibited the production of inflammatory cells in DMBA/TPA-induced skin/tumors. Further experiments showed that baicalein reduced TPA-induced skin hyperplasia as well as infiltration of polymorphonuclear leukocytes in the dermis. In conclusion, our data suggest that baicalein inhibits DMBA/TPA-induced skin tumorigenesis by suppressing proliferation and inflammation and promoting apoptosis.
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[The effect of drainage in cavities on preventing from grade B and C of the pancreatic fistula after pancreaticoduodenectomy].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 08-21-2013
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To explore the effect of drainage in cavities on preventing from grade B and C of the pancreatic fistula after pancreaticoduodenectomy (PD).
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Identification and characterization of microRNAs in the developing maize endosperm.
Genomics
PUBLISHED: 08-04-2013
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MicroRNAs (miRNAs) are non-coding RNAs that are approximately 20-22 nucleotides long. miRNAs have been shown to be important regulators that control a large variety of biological functions in eukaryotic cells. To investigate the roles of miRNAs in maize endosperm development, two small RNA libraries of maize endosperm at two developmental stages were sequenced. A total of 17,773,394 and 18,586,523 small RNA raw reads were obtained, respectively. Further analysis identified and characterized 95 known miRNAs belonging to 20 miRNA families. In addition, 18 novel miRNAs were identified and grouped into 11 families. Potential targets for 5 of the novel miRNA families were successfully predicted. We had also identified 12 corresponding miRNAs* of these novel miRNAs. In summary, we investigated expression patterns of miRNA in maize endosperm at key developmental stages and identified miRNAs that are likely to playing an important role in endosperm development.
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Safety and efficiency of thulium laser prostate resection for the treatment of benign prostatic hyperplasia in large prostates.
Lasers Med Sci
PUBLISHED: 07-16-2013
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Thulium laser resection of the prostate-tangerine technique (TmLRP-TT) dissects whole prostatic lobes off the surgical capsule, similar to peeling a tangerine. The present study aimed to evaluate the safety and efficacy of TmLRP-TT for older symptomatic benign prostatic hyperplasia patients with large prostates during 18 months of follow-up. A prospective analysis of 95 consecutive patients with large prostates (>80 ml) who underwent surgical treatment using TmLRP-TT was carried out. All patients were evaluated preoperatively and at 1, 6, 12, and 18 months postoperatively by the International Prostate Symptom Score (IPSS), quality of life (QoL), maximum urinary flow rate (Q max), postvoid residual urine volume (PVR), International Index of Erectile Function 5 (IIEF-5), urine analysis, and urine culture. Perioperative complications were recorded and graded by the modified Clavien classification system (CCS). Mean preoperative prostate volume was 106.81?±?24.79 ml. TmLRP-TT was successfully completed in all patients. The mean operative duration, catheterization time, and hospital stay were 95.36?±?27.06 min, 2.25?±?0.9 days, and 5.39?±?1.18 days, respectively. The decrease in mean hemoglobin level was 1.23?±?0.72 g/dl, and that in mean serum sodium level was 0.71?±?2.56 mmol/l. Within the observation period of 18 months, the patients showed an improvement in IPSS (20.01?±?7.08 vs. 4.96?±?3.68), QoL (4.10?±?1.16 vs. 1.23?±?1.30), Q max (8.14?±?3.81 ml/s vs. 18.33?±?2.56 ml/s) and PVR (102.70?±?70.64 ml vs. 20.28?±?30.02 ml), compared with baseline values (P?
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[Influence of different surface roughness on the wear performance of several commonly used dental materials].
Shanghai Kou Qiang Yi Xue
PUBLISHED: 07-16-2013
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To evaluate the influence of different surface roughness on the wear performance of several commonly used dental materials.
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microRNA-449a functions as a tumor-suppressor in gastric adenocarcinoma by targeting Bcl-2.
Oncol Lett
PUBLISHED: 06-30-2013
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microRNAs (miRNAs or miRs) may function as oncogenes or tumor suppressors. The present study identified that miR-449a was downregulated in human gastric cancer. The overexpression of miR-449a inhibited gastric adenocarcinoma cell growth and promoted cell apoptosis in the MGC-803 and SGC-7901 gastric adenocarcinoma cell lines. Subsequently, Bcl-2 was identified as a potential miR-449a target by bioinformatics analysis. It was also shown that Bcl-2 was negatively regulated by miR-449a at the post-transcriptional level, via a specific target site within the 3-untranslated region (3UTR), by luciferase reporter assay. The expression of miR-449a induced cell apoptosis, as observed by TdT-mediated dUTP nick end labeling and caspase 3/7 assays, and was rescued by Bcl-2 expression. Therefore, these observations indicate that miR-449a acts as a tumor suppressor by targeting the Bcl-2 gene and that it promotes gastric adenocarcinoma cell apoptosis via Bcl-2. The findings of this study contribute to or current understanding of the functions of miR-449a in gastric adenocarcinoma.
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Variations in NAG-1 expression of human gastric carcinoma and normal gastric tissues.
Exp Ther Med
PUBLISHED: 06-18-2013
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Nonsteroidal anti-inflammatory drug-activated gene-1 (NAG-1), a member of the transforming growth factor ? (TGF-?) superfamily, has been demonstrated to possess antitumorigenic and proapoptotic activities in gastric cancer cells. In the present study, the expression of NAG-1 was assessed in human gastric carcinoma, tumor-adjacent normal tissues and normal gastric mucosa, with the aim to investigate the role of NAG-1 in the carcinogenesis and development of gastric carcinoma. NAG-1 protein expression was evaluated using immunohistochemical staining, while the expression of NAG-1 mRNA was evaluated using reverse transcription-polymerase chain reaction. It was observed that adenocarcinoma tissues had a lower expression of NAG-1 than normal gastric tissues. Furthermore, moderately and well-differentiated adenocarcinoma tissues expressed more NAG-1 protein than the poorly differentiated adenocarcinoma tissues. The expression of NAG-1 protein in adenocarcinoma tissues did not correlate with tumor-node-metastasis staging, infiltration degree or tumor size. The NAG-1 mRNA expression in adenocarcinoma tissues was also lower than that in normal gastric tissues. In conclusion, NAG-1 was poorly expressed in adenocarcinoma tissues and inversely correlated with the degree of tumor differentiation. These results indicate that NAG-1 may have an anti-oncogenic function in the carcinogenesis and development of gastric carcinoma, and that its attenuated or absent expression may lead to gastric carcinogenesis.
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Elevated NKT cell levels in adults with severe chronic immune thrombocytopenia.
Exp Ther Med
PUBLISHED: 06-15-2013
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The aim of this study was to investigate the frequency of circulating natural killer T (NKT) cells and regulatory T cells (Tregs), as well as serum cytokine profiles, in adult chronic primary immune thrombocytopenia (ITP). The frequency of circulating T cell receptor (TCR) V?24(+)V?11(+)CD3(+) NKT cells and CD4(+)CD25(+)CD127(-/low) Tregs was measured using multi-color flow cytometry. The serum concentrations of 11 cytokines were determined with a cytometric bead assay. The frequency of circulating NKT cells in patients with ITP was 0.13±0.03%, whereas the frequency in healthy controls was 0.07±0.01% of CD3(+) (P>0.05). However, the frequency of NKT cells in patients with ITP with platelet counts ?20×10(9)/l (0.22±0.05%) was significantly higher than that in patients with platelet counts >20×10(9)/l (0.05±0.01%; P<0.05) and that in healthy controls (0.07±0.01%; P<0.05). The frequency of peripheral Tregs was comparable between patients with ITP (3.97±0.44% of CD4(+)) and healthy controls (3.69±0.31%; P>0.05). No significant differences were observed in the serum concentrations of 11 cytokines between patients with ITP and healthy controls, despite the fact that the serum levels of interleukin (IL)-12p70, IL-8, IL-4, interferon (IFN)-? and tumor necrosis factor (TNF)-? in patients with ITP were higher than those in the healthy controls. The platelet count was negatively correlated with the frequency of circulating NKT cells in chronic ITP. These results indicate that NKT cells may be involved in ITP with severe thrombocytopenia, and NKT and Tregs may be important in cytokine deregulation in chronic ITP.
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Two-micron thulium laser resection of the distal ureter and bladder cuff during nephroureterectomy for upper urinary tract urothelial carcinoma.
Lasers Med Sci
PUBLISHED: 06-04-2013
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The thulium laser (Tm-laser) technique has been used in the management of many urologic conditions. The present study aimed to evaluate the use of this technique for distal ureter and bladder cuff (DUBC) excision during nephroureterectomy for upper urinary tract urothelial carcinoma (UUT-UC). Fifty-eight patients with UUT-UC who underwent radical nephroureterectomy were included in this retrospective study. DUBC was managed by open excision in 24 cases, by transurethral electrosurgery in 17 cases, and by transurethral Tm-laser in 17 cases. Perioperative measures and oncologic outcomes were compared among the three groups. Furthermore, 11 human ureteral segments were collected to measure the burst pressure and show physical pressure tolerance, and six ureteral segments were assessed histologically to investigate the sealing effect. Operative time and hospital stay were significantly longer, and intraoperative blood loss was significantly greater in the open excision group than in the electrosurgery and Tm-laser groups (P?
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[Wear resistance of tooth hard tissue opposing dental alloy material in an adjustable wear simulator].
Shanghai Kou Qiang Yi Xue
PUBLISHED: 05-28-2013
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To evaluate wear resistance of human enamel by a customized adjustable wear simulator.
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Clinical features and prognosis of patients with benign thyroid disease accompanied by an incidental papillary carcinoma.
Asian Pac. J. Cancer Prev.
PUBLISHED: 04-30-2013
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To investigate the clinical features and prognosis of papillary thyroid carcinoma (PTC) with a background of benign disease.
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Loss of ?-arrestin 2 exacerbates experimental autoimmune encephalomyelitis due to a reduced number of Foxp3(+) CD4(+) regulatory T cells.
Immunology
PUBLISHED: 04-27-2013
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?-Arrestins are well-known regulators and mediators of G protein-coupled receptor (GPCR) signalling, and accumulating evidence reveals that they are functionally involved in inflammation and autoimmune diseases. Of the 2 ?-arrestins, ?-arrestin 1 is documented to play regulatory roles in an animal model of multiple sclerosis (MS), whereas the role of ?-arrestin 2 is less clear. Here, we showed that ?-arrestin 2-deficient mice displayed the exacerbated and sustained symptoms of experimental autoimmune encephalomyelitis (EAE), an animal model of MS. At the cellular level, deficiency of ?-arrestin 2 led to a decreased number of Foxp3(+) CD4(+) regulatory T cells (Tregs) in peripheral lymphoid organs of EAE mice. Consistently, our in vitro observations also revealed that loss of ?-arrestin 2 impaired the conversion of Foxp3(-) CD4(+) T cells into Foxp3(+) CD4(+) inducible Treg cells (iTregs). Taken together, our data suggest that ?-arrestin 2 plays a regulatory role in MS, that is opposite to ?-arrestin 1, in autoimmune diseases such as MS, which is at least partially through regulation of iTreg differentiation. This article is protected by copyright. All rights reserved.
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Deficiency of ?-arrestin1 ameliorates collagen-induced arthritis with impaired TH17 cell differentiation.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-15-2013
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Rheumatoid arthritis (RA) is an inflammatory disease in which interleukin 17 (IL-17)-producing T helper 17 (T(H)17) cells have been critically involved. We show that in patients with RA, the expression of a multifunctional regulator ?-arrestin1 was significantly up-regulated in peripheral and synovial CD4(+) T cells, which correlated well with active phases of RA. In collagen-induced arthritis, deficiency of ?-arrestin1 ameliorated disease with decreased T(H)17 cell differentiation, proinflammatory cytokine production, synovitis, and cartilage and bone destruction. Further mechanistic study reveals that ?-arrestin1 promoted signal transducer and activator of transcription 3 (STAT3) activation required for T(H)17 cell differentiation through scaffolding the interaction of Janus kinase 1 and STAT3. These findings indicate a critical role for ?-arrestin1 in the pathogenesis of collagen-induced arthritis and T(H)17 cell differentiation and suggest ?-arrestin1 as a potential diagnostic biomarker and therapeutic target for RA.
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Immune adaptor ADAP in T cells regulates HIV-1 transcription and cell-cell viral spread via different co-receptors.
Retrovirology
PUBLISHED: 04-09-2013
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Immune cell adaptor protein ADAP (adhesion and degranulation-promoting adaptor protein) mediates aspects of T-cell adhesion and proliferation. Despite this, a connection between ADAP and infection by the HIV-1 (human immunodeficiency virus-1) has not been explored.
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Surface properties and corrosion behavior of co-cr alloy fabricated with selective laser melting technique.
Cell Biochem. Biophys.
PUBLISHED: 04-05-2013
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We sought to study the corrosion behavior and surface properties of a commercial cobalt-chromium (Co-Cr) alloy which was fabricated with selective laser melting (SLM) technique. For this purpose, specimens were fabricated using different techniques, such as SLM system and casting methods. Surface hardness testing, microstructure observation, surface analysis using X-ray photoelectron spectroscopy (XPS) and electrochemical corrosion test were carried out to evaluate the corrosion properties and surface properties of the specimens. We found that microstructure of SLM specimens was more homogeneous than that of cast specimens. The mean surface hardness values of SLM and cast specimens were 458.3 and 384.8, respectively; SLM specimens showed higher values than cast ones in hardness. Both specimens exhibited no differences in their electrochemical corrosion properties in the artificial saliva through potentiodynamic curves and EIS, and no significant difference via XPS. Therefore, we concluded that within the scope of this study, SLM-fabricated restorations revealed good surface properties, such as proper hardness, homogeneous microstructure, and also showed sufficient corrosion resistance which could meet the needs of dental clinics.
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The Drosophila F-box protein dSkp2 regulates cell proliferation by targeting Dacapo for degradation.
Mol. Biol. Cell
PUBLISHED: 04-03-2013
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Cell cycle progression is controlled by a complex regulatory network consisting of interacting positive and negative factors. In humans, the positive regulator Skp2, an F-box protein, has been a subject of intense investigation in part because of its oncogenic activity. By contrast, the molecular and developmental functions of its Drosophila homologue, dSkp2, are poorly understood. Here we investigate the role of dSkp2 by focusing on its functional relationship with Dacapo (Dap), the Drosophila homologue of the cyclin-dependent kinase inhibitors p21(cip1)/p27(kip1)/p57(kip2). We show that dSkp2 interacts physically with Dap and has a role in targeting Dap for ubiquitination and proteasome-mediated degradation. We present evidence that dSkp2 regulates cell cycle progression by antagonizing Dap in vivo. dSkp2 knockdown reduces cell density in the wing by prolonging the cell doubling time. In addition, the wing phenotype caused by dSkp2 knockdown resembles that caused by dap overexpression and can be partially suppressed by reducing the gene dose of dap. Our study thus documents a conserved functional relationship between dSkp2 and Dap in their control of cell cycle progression, suggesting the possibility of using Drosophila as a model system to study Skp2-mediated tumorigenesis.
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Reproducibility of subfoveal choroidal thickness measurements with enhanced depth imaging by spectral-domain optical coherence tomography.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 03-13-2013
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To measure the interobserver reproducibility and intra-observer reproducibility of subfoveal choroidal thickness measurements performed by enhanced depth imaging of spectral-domain optical coherence tomography (EDI-OCT) in a population-based setting.
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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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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.