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Find video protocols related to scientific articles indexed in Pubmed.
Tri-ortho-cresyl phosphate- induces autophagy of rat spermatogonial stem cells.
Reproduction
PUBLISHED: 11-12-2014
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Tri-ortho -cresyl phosphate (TOCP) has been widely used as plasticizers, plastic softeners, and flame-retardants in industry and reported to have a deleterious effect on the male reproductive system in animals besides delayed neurotoxicity. Our preliminary results found that TOCP could disrupt the seminiferous epithelium in the testis and inhibit spermatogenesis, but the precise mechanism is yet to be elucidated. The present study shows that TOCP inhibited viability of rat spermatogonial stem cells in a dose-dependent manner. TOCP couldn't lead to cell cycle arrest in the cells; the mRNA levels of p21, p27, p53 and cyclin D1 in the cells were also not affected by TOCP. Meanwhile, TOCP didn't induce apoptosis of rat spermatogonial stem cells. After treatment with TOCP, however, both LC3-II and the ratio of LC3-II/LC3-I were markedly increased; autophagy proteins atg5 and Beclin 1 were also increased after treated with TOCP, indicating TOCP could induce autophagy in the cells. Ultrastructural observation under the transmission electron microscopy (TEM) indicated that autophagic vesicles in the cytoplasm containing extensively degraded organelles such as mitochondria and endoplasmic reticulum increased significantly after the cells were treated with TOCP. In summary, we have shown that TOCP can inhibit viability of rat spermatogonial stem cells and induce autophagy of the cells, without affecting cell cycle and apoptosis.
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[Levels of complement components C3a and C5a in renal injury among trichloroethylene-sensitized BALB/c mice].
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi
PUBLISHED: 08-30-2014
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To determine the levels of complement components C3a and C5a in the kidneys of trichloroethylene (TCE)-sensitized BALB/c mice, and to investigate the role of complement components in TCE-induced renal injury among BALB/c mice.
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Regional traumatic limb hypothermia attenuates distant hepatic and renal injury following blast limb trauma in rats.
J Trauma Acute Care Surg
PUBLISHED: 08-28-2014
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Blast limb injury was reported to result in distant organ injury including the lungs, which can be attenuated with transient regional hypothermia (RH) to the injured limb. We aimed to further study hepatic and renal injuries following blast limb trauma and also to evaluate the protective effects of regional traumatic limb hypothermia on such injuries in rats.
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[Early screening of developmental dysplasia of the hip among hospitalized children].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 08-23-2014
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To summarize retrospectively developmental dysplasia of the hip (DDH) screening of children within 36 months.
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Correlation between Congenital Heart Defects and maternal copper and zinc concentrations.
Birth Defects Res. Part A Clin. Mol. Teratol.
PUBLISHED: 08-18-2014
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The aim of this study was to investigate the correlation between maternal concentrations of copper and zinc and the risk of having an infant with a congenital heart defect (CHD).
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A ten liter stacked microbial desalination cell packed with mixed ion-exchange resins for secondary effluent desalination.
Environ. Sci. Technol.
PUBLISHED: 08-08-2014
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The architecture and performance of microbial desalination cell (MDC) have been significantly improved in the past few years. However, the application of MDC is still limited in a scope of small-scale (milliliter) reactors and high-salinity-water desalination. In this study, a large-scale (>10 L) stacked MDC packed with mixed ion-exchange resins was fabricated and operated in the batch mode with a salt concentration of 0.5 g/L NaCl, a typical level of domestic wastewater. With circulation flow rate of 80 mL/min, the stacked resin-packed MDC (SR-MDC) achieved a desalination efficiency of 95.8% and a final effluent concentration of 0.02 g/L in 12 h, which is comparable with the effluent quality of reverse osmosis in terms of salinity. Moreover, the SR-MDC kept a stable desalination performance (>93%) when concentrate volume decreased from 2.4 to 0.1 L (diluate/concentrate volume ratio increased from 1:1 to 1:0.04), where only 0.875 L of nonfresh water was consumed to desalinate 1 L of saline water. In addition, the SR-MDC achieved a considerable desalination rate (95.4 mg/h), suggesting a promising application for secondary effluent desalination through deriving biochemical electricity from wastewater.
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Lewis acid triggered reactivity of a Lewis base stabilized scandium-terminal imido complex: C-H bond activation, cycloaddition, and dehydrofluorination.
J. Am. Chem. Soc.
PUBLISHED: 07-24-2014
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A stable scandium-terminal imido complex is activated by borane to form an unsaturated terminal imido complex by removing the coordinated Lewis base, 4-(dimethylamino)pyridine, from the metal center. The ensuing terminal imido intermediate can exist as a THF adduct and/or undergo cycloaddition reaction with an internal alkyne, C-H activation of a terminal alkene, and dehydrofluorination of fluoro-substituted benzenes or alkanes at room temperature. DFT investigations further highlight the ease of C-H activation for terminal alkene and fluoroarene. They also shed light on the mechanistic aspects of these two reactions.
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Risk factors for the second contralateral hip fracture in elderly patients: a systematic review and meta-analysis.
Clin Rehabil
PUBLISHED: 07-17-2014
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To achieve a quantitative and comprehensive conclusion concerning the risk factors for the second contralateral hip fracture in elderly patients with initial hip fractures.
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Identification of apolipoprotein C-I as a potential Wilms' tumor marker after excluding inflammatory factors.
Int J Mol Sci
PUBLISHED: 07-15-2014
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Wilms' tumor is one of the most common malignant tumors observed in children, and its early diagnosis is important for late-stage treatment and prognosis. We previously screened and identified protein markers for Wilms' tumor; however, these markers lacked specificity, and some were associated with inflammation. In the current study, serum samples from children with Wilms' tumors were compared with those of healthy controls and patients with systemic inflammatory response syndrome (SIRS). After exclusion of factors associated with inflammation, specific protein markers for Wilms' tumors were identified. After comparing the protein peak values obtained from all three groups, a protein with a m/z of 6438 Da was specified. Purification and identification of the target protein using high-pressure liquid chromatography (HPLC) and two-dimensional liquid chromatography-linearion trap mass spectrometry(2D-LC-LTQ-MS) mass spectrometry, respectively, revealed that it was apolipoprotein C-I (APO C-I). Thus, APO C-I is a specific protein marker for Wilms' tumor.
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A novel rat model of cardiopulmonary bypass for deep hypothermic circulatory arrest without blood priming.
Chin. Med. J.
PUBLISHED: 04-09-2014
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Large animal cardiopulmonary bypass (CPB) models are expensive, and prevent assessment of neurocognitive function, and difficulties with long-term recovery. The purpose of this study was to establish a novel rat model of cardiopulmonary bypass for deep hypothermic circulatory arrest without blood priming.
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CERKL interacts with mitochondrial TRX2 and protects retinal cells from oxidative stress-induced apoptosis.
Biochim. Biophys. Acta
PUBLISHED: 04-02-2014
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Mutations in the ceramide kinase-like gene (CERKL) are associated with severe retinal degeneration. However, the exact function of the encoded protein (CERKL) remains unknown. Here we show that CERKL interacts with mitochondrial thioredoxin 2 (TRX2) and maintains TRX2 in the reduced redox state. Overexpression of CERKL protects cells from apoptosis under oxidative stress, whereas suppressing CERKL renders cells more sensitive to oxidative stress. In zebrafish, CERKL protein prominently locates in the outer segment and inner segment of the photoreceptor of the retina. Knockdown of CERKL in the zebrafish leads to an increase of retinal cell death, including cone and rod photoreceptor degeneration. Signs of oxidative damage to macromolecules were also detected in CERKL deficient zebrafish retina. Our results show that CERKL interacts with TRX2 and plays a novel key role in the regulation of the TRX2 antioxidant pathway and, for the first time, provides an explanation of how mutations in CERKL may lead to retinal cell death.
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Complex-formation-enhanced fluorescence quenching effect for efficient detection of picric acid.
Chemistry
PUBLISHED: 03-26-2014
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Amine-functionalized ?-cyanostilbene derivatives (Z)-2-(4-aminophenyl)-3-(4-butoxyphenyl)acrylonitrile (ABA) and (Z)-3-(4-butoxyphenyl)-2-[4-(butylamino)phenyl]acrylonitrile (BBA) were designed for specific recognition of picric acid (PA), an environmental and biological pollutant. The 1:1 host-guest complexes formed between the chemosensors and PA enhanced fluorescence quenching, thus leading to sensitive and selective detection in aqueous media and the solid phase.
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Outbreak of carbapenemase-producing Klebsiella pneumoniae neurosurgical site infections associated with a contaminated shaving razor used for preoperative scalp shaving.
Am J Infect Control
PUBLISHED: 03-21-2014
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Between July 5 and 21, 2011, an outbreak of neurosurgical site infections with carbapenemase-producing Klebsiella pneumonia occurred in a tertiary care hospital. The outbreak affected 7 patients. The subsequent investigation revealed that a barber's contaminated shaving razor may have caused the carbapenemase-producing Klebsiella pneumonia outbreak. Standardized skin preparation performed by registered nurses using sterilized instruments should be emphasized.
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Clioquinol induces pro-death autophagy in leukemia and myeloma cells by disrupting the mTOR signaling pathway.
Sci Rep
PUBLISHED: 03-14-2014
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Clioquinol is an anti-microbial drug, and it was recently found to induce cancer cell death. In the present study, clioquinol was found to trigger autophagy by inducing LC3 lipidation and autophagosome formation which was abolished by an autophagy inhibitor 3-methyladenine. Further study showed clioquinol displayed no effects on PI3KC3 or Beclin 1 expression but downregulated the expression and the enzymatic activity of mammalian target of Rapamycin (mTOR), a critical modulator of autophagy. Moreover, clioquinol inhibited the catalytic activity of the mTOR complex 1, thus suppressing phosphorylation of P70S6K and 4E-BP1, two major proteins associated with autophagy in the mTORC1 signaling pathway. Clioquinol induced leukemia and myeloma cell apoptosis, however, addition of autophagy inhibitor 3-methyladenine attenuated this kind of cell death. Therefore, this study demonstrated that clioquinol induces autophagy in associated with apoptosis in leukemia and myeloma cells by disrupting mTOR signaling pathway.
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Meta-analysis of risk factors for the second hip fracture (SHF) in elderly patients.
Arch Gerontol Geriatr
PUBLISHED: 02-24-2014
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This study aims to quantitatively summarize the risk factors for the incidence of SHF. A meta-analysis was performed with the data obtained from 22 relevant papers published in Pubmed, Embase and Cochrane central database (all through January 2014) following strict selection. The pooled odds ratios (ORs) or standardized mean difference (SMD) with 95% confidence intervals (CIs) were calculated for potential risk factors associated with SHF. Our meta-analysis indicated the significant risk factors for SHF were female (OR, 1.46; 95%CI, 1.29-1.66), living in institutions (OR, 2.23; 95%CI, 1.29-3.83), osteoporosis (Singh index (SI) 1-3) (OR, 10.02; 95%CI, 5.41-18.57), low vision (OR, 2.09; 95%CI, 1.06-4.12), dementia (OR, 1.89; 95%CI, 1.47-2.43), Parkinson (OR, 2.90; 95%CI, 1.41-5.95), cardiac diseases (OR, 1.32; 95%CI, 1.02-1.70) and respiratory disease (OR, 1.97; 95%CI, 1.16-3.32). Related strategies must be implemented on those involved with above-mentioned medical conditions to effectively prevent a SHF.
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Compressed sensing based virtual-detector photoacoustic microscopy in vivo.
J Biomed Opt
PUBLISHED: 01-29-2014
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Photoacoustic microscopy (PAM) is becoming a vital tool for various biomedical studies, including functional and molecular imaging of cancer. However, due to the use of a focused ultrasonic transducer for photoacoustic detection, the image quality of conventional PAM degrades rapidly away from the ultrasonic focal zone. To improve the image quality of PAM for out-of-focus regions, we have developed compressed sensing based virtual-detector photoacoustic microscopy (CS-PAM). Through phantom and in vivo experiments, it has been demonstrated that CS-PAM can effectively extend the depth of focus of PAM, and thus may greatly expand its potential biomedical applications.
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The inhibitory effect of quercetin on asymmetric dimethylarginine-induced apoptosis is mediated by the endoplasmic reticulum stress pathway in glomerular endothelial cells.
Int J Mol Sci
PUBLISHED: 01-24-2014
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Asymmetric dimethylarginine (ADMA) is considered an independent mortality and cardiovascular risk factor in chronic kidney disease (CKD) patients, and contributes to the development of renal fibrosis. Quercetin (QC), a natural component of foods, protects against renal injury. Here, we explored the possible mechanisms that are responsible for ADMA-induced renal fibrosis and the protective effect of QC. We found that ADMA treatment activated the endoplasmic reticulum (ER) stress sensor proteins phosphorylated protein kinase RNA-activated-like ER kinase (PERK) and inositol requiring-1? (IRE1), which correspondingly induced C/EBP homologous protein (CHOP) expression and phosphorylated c-Jun N-terminal kinase (JNK) phosphorylation in glomerular endothelial cells (GEnCs). Following this, ADMA promoted ER stress-induced apoptosis and resulted in transforming growth factor ? (TGF-?) expression in GEnCs. SP600125, an inhibitor of JNK, and CHOP siRNA protected against ADMA-induced cell apoptosis and TGF-? expression. QC prevented ADMA-induced PERK and IRE1 apoptotic ER stress pathway activation. Also, ADMA-induced GEnCs apoptosis and TGF-? expression was reduced by QC. Overexpression of CHOP blocked QC-mediated protection from apoptosis in ER stressed cells. Overall, these observations indicate that ADMA may induce GEnCs apoptosis and TGF-? expression by targeting the PERK-CHOP and IRE1-JNK pathway. In addition, drugs such as QC targeting ER stress may hold great promise for the development of novel therapies against ADMA-induced renal fibrosis.
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Wnt inhibitory factor-1 functions as a tumor suppressor through modulating Wnt/?-catenin signaling in neuroblastoma.
Cancer Lett.
PUBLISHED: 01-22-2014
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Neuroblastoma is the most common extracranial solid tumor in childhood and is associated with serious morbidity and mortality. The effective treatment of neuroblastoma remains one of the major challenges in pediatric oncology. The Wnt signaling pathway has been shown to play a significant role in the pathogenesis of adult and pediatric tumors. WIF-1 has been identified as an important Wnt antagonist which inhibits Wnt/?-catenin signaling by directly binding to Wnt proteins. However, the expression and function of WIF-1 in neuroblastoma remains unknown. The present study showed that WIF-1 was downregulated with high level promoter methylation in neuroblastoma cells, and was significantly upregulated after exposure to demethylating agent. This finding suggests that downregulation of WIF-1 was associated with its promoter methylation in neuroblastoma. To further study the potential function of WIF-1 in neuroblastoma, we constructed a plasmid that over-expressed WIF-1 and transfected the plasmid into one neuroblastoma cell line SK-N-SH. We found that restoration of WIF-1 inhibited the growth and proliferation of neuroblastoma cells in vitro. Moreover, Wnt/?-catenin signaling activity and target genes expression were reduced by WIF-1 restoration. These results provide support that WIF-1 is downregulated and functions as a tumor suppressor by antagonizing Wnt/?-catenin signaling in neuroblastoma, suggesting a potential role as a therapeutic target in neuroblastoma.
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Masticatory Muscles Dysfunction after CT-guided Percutaneous Trigeminal Radiofrequency Thermocoagulation for Trigeminal Neuralgia: A Detailed Analysis.
Pain Pract
PUBLISHED: 01-21-2014
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The aim of this study was to investigate the severity and the natural course of masticatory muscles weakness that developed after CT-guided percutaneous trigeminal radiofrequency thermocoagulation (PT-RFT) for the treatment of idiopathic trigeminal neuralgia (ITN).
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Lower number of plasmacytoid dendritic cells in peripheral blood of children with bronchiolitis following respiratory syncytial virus infection.
Influenza Other Respir Viruses
PUBLISHED: 01-13-2014
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Dendritic cells (DCs) are key mediators of allergic airway inflammation. Thus, it is important to understand the relationship between respiratory syncytial virus (RSV) infection and DCs, especially in children with RSV bronchiolitis.
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Dissociable mechanisms of speed-accuracy tradeoff during visual perceptual learning are revealed by a hierarchical drift-diffusion model.
Front Neurosci
PUBLISHED: 01-01-2014
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Two phenomena are commonly observed in decision-making. First, there is a speed-accuracy tradeoff (SAT) such that decisions are slower and more accurate when instructions emphasize accuracy over speed, and vice versa. Second, decision performance improves with practice, as a task is learnt. The SAT and learning effects have been explained under a well-established evidence-accumulation framework for decision-making, which suggests that evidence supporting each choice is accumulated over time, and a decision is committed to when the accumulated evidence reaches a decision boundary. This framework suggests that changing the decision boundary creates the tradeoff between decision speed and accuracy, while increasing the rate of accumulation leads to more accurate and faster decisions after learning. However, recent studies challenged the view that SAT and learning are associated with changes in distinct, single decision parameters. Further, the influence of speed-accuracy instructions over the course of learning remains largely unknown. Here, we used a hierarchical drift-diffusion model to examine the SAT during learning of a coherent motion discrimination task across multiple training sessions, and a transfer test session. The influence of speed-accuracy instructions was robust over training and generalized across untrained stimulus features. Emphasizing decision accuracy rather than speed was associated with increased boundary separation, drift rate and non-decision time at the beginning of training. However, after training, an emphasis on decision accuracy was only associated with increased boundary separation. In addition, faster and more accurate decisions after learning were due to a gradual decrease in boundary separation and an increase in drift rate. The results suggest that speed-accuracy instructions and learning differentially shape decision-making processes at different time scales.
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Intravascular optical-resolution photoacoustic tomography with a 1.1 mm diameter catheter.
PLoS ONE
PUBLISHED: 01-01-2014
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Photoacoustic imaging is an emerging technology that can provide anatomic, functional, and molecular information about biological tissue. Intravascular spectroscopic and molecular photoacoustic imaging can potentially improve the identification of atherosclerotic plaque composition, the detection of inflammation, and ultimately the risk stratification of atherosclerosis. In this study, a first-of-its-kind intravascular optical-resolution photoacoustic tomography (OR-PAT) system with a 1.1 mm diameter catheter is developed, offering optical-diffraction limited transverse resolution as fine as 19.6 ?m, ? 10-fold finer than that of conventional intravascular photoacoustic and ultrasonic imaging. To offer complementary imaging information and depth, the system also acquires co-registered intravascular ultrasound images in parallel. Imaging of an iliac stent and a lipid phantom shows that the high resolution and contrast of OR-PAT can enable improved stent implantation guidance and lipid identification. In the future, these capabilities may ultimately improve the diagnosis and interventional treatment of vulnerable atherosclerotic plaques, which are prone to cause thrombotic complications such as myocardial infarction and stroke.
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A?-induced microglial cell activation is inhibited by baicalin through the JAK2/STAT3 signaling pathway.
Int. J. Neurosci.
PUBLISHED: 12-12-2013
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Baicalin has shown multiple neuroprotective biological activities, including antiapoptotic and anti-inflammatory functions in neurodegeneration diseases. However, whether baicalin can regulate A?-induced microglial activation or inhibit inflammatory cytokine secretion has not been confirmed. We demonstrated that baicalin can inhibit beta amyloid peptides (A?42)-induced BV2 microglial cell proliferation, reduce the expression of CD11b, decrease chemotactic ability of BV2 cells and significantly inhibit the secretion of IL-6, TNF-? and NO. Moreover, baicalin pretreatment can effectively inhibit A?-induced phosphorylation of JAK2 and STAT3. Baicalin can inhibit A?-induced microglial cell activation by regulating the JAK2/STAT3 signaling pathway in AD transgenic mice. The modulation of microglial proliferation, activation and secretion by baicalin could be a promising therapeutic option for the treatment of Alzheimers disease.
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A nanomembrane-based wavelength-tunable high-speed single-photon-emitting diode.
Nano Lett.
PUBLISHED: 11-08-2013
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We demonstrate an all-electrically operated wavelength-tunable on demand single-photon source for the first time. The device consists of a light-emitting diode in the form of a semiconductor nanomembrane containing self-assembled quantum dots integrated onto a piezoelectric crystal. Triggered single photons are generated via injection of ultrashort electrical pulses into the diode, while their energy can be precisely tuned over a broad range by varying the voltage applied to the piezoelectric crystal. High speed operation of this single-photon-emitting diode up to 0.8 GHz is demonstrated. These results represent an important step toward the realization of electrically driven sources of indistinguishable photons on demand.
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Complement activation and liver impairment in trichloroethylene-sensitized BALB/c mice.
Int. J. Toxicol.
PUBLISHED: 11-07-2013
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Our recent studies have shown that trichloroethylene (TCE) was able to induce multisystem injuries in the form of occupational medicamentosa-like dermatitis, including skin, kidney, and liver damages. However, the role of complement activation in the immune-mediated liver injury is not known. This study examined the role of complement activation in the liver injury in a mouse model of TCE-induced sensitization. Treatment of female BALB/c mice with TCE under specific dosing protocols resulted in skin inflammation and sensitization. Skin edema and erythema occurred in TCE-sensitized groups. Trichloroethylene sensitization produced liver histopathological lesions, increased serum alanine aminotransferase, aspartate transaminase activities, and the relative liver weight. The concentrations of serum complement components C3a-desArg, C5a-desArg, and C5b-9 were significantly increased in 24-hour, 48-hour, and 72-hour sensitization-positive groups treated with TCE and peaked in the 72-hour sensitization-positive group. Depositions of C3a, C5a, and C5b-9 into the liver tissue were also revealed by immunohistochemistry. Immunofluorescence further verified high C5b-9 expression in 24-hour, 48-hour, and 72-hour sensitization-positive groups in response to TCE treatment. Reverse transcription-polymerase chain reaction detected C3 messenger RNA expression in the liver, and this was significantly increased in 24-hour and 48-hour sensitization-positive groups with a transient reduction at 72 hours. These results provide the first experimental evidence that complement activation may play a key role in the generation and progression of immune-mediated hepatic injury by exposure to TCE.
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The role of synaptic activity in the regulation of amyloid beta levels in Alzheimers disease.
Neurobiol. Aging
PUBLISHED: 11-03-2013
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Alzheimers disease (AD) is the most common form of dementia. Accumulation of amyloid-beta (A?) peptides is regarded as the critical component associated with AD pathogenesis, which is derived from the amyloid precursor protein (APP) cleavage. Recent studies suggest that synaptic activity is one of the most important factors that regulate A? levels. It has been found that synaptic activity facilitates APP internalization and influences APP cleavage. Glutamatergic, cholinergic, serotonergic, leptin, adrenergic, orexin, and gamma-amino butyric acid receptors, as well as the activity-regulated cytoskeleton-associated protein (Arc) are all involved in these processes. The present review summarizes the evidence for synaptic activity-modulated A? levels and the mechanisms underlying this regulation. Interestingly, the immediate early gene product Arc may also be the downstream signaling molecule of several receptors in the synaptic activity-modulated A? levels. Elucidating how A? levels are regulated by synaptic activity may provide new insights in both the understanding of the pathogenesis of AD and in the development of therapies to slow down the progression of AD.
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Purified hepatitis B virus induces human mesangial cell proliferation and extracellular matrix expression in vitro.
Virol. J.
PUBLISHED: 08-01-2013
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Hepatitis B virus (HBV) induces proliferation of human mesangial cells (HMCs), and extracellular matrix expression through the deposition of immune complexes in renal tissue. However, it is unclear whether HBV can directly affect HMCs. In this study, the effects of purified HBV on HMC proliferation and extracellular matrix expression in vitro was determined.
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Choosing the rules: distinct and overlapping frontoparietal representations of task rules for perceptual decisions.
J. Neurosci.
PUBLISHED: 07-19-2013
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Behavior is governed by rules that associate stimuli with responses and outcomes. Human and monkey studies have shown that rule-specific information is widely represented in the frontoparietal cortex. However, it is not known how establishing a rule under different contexts affects its neural representation. Here, we use event-related functional MRI (fMRI) and multivoxel pattern classification methods to investigate the human brains mechanisms of establishing and maintaining rules for multiple perceptual decision tasks. Rules were either chosen by participants or specifically instructed to them, and the fMRI activation patterns representing rule-specific information were compared between these contexts. We show that frontoparietal regions differ in the properties of their rule representations during active maintenance before execution. First, rule-specific information maintained in the dorsolateral and medial frontal cortex depends on the context in which it was established (chosen vs specified). Second, rule representations maintained in the ventrolateral frontal and parietal cortex are independent of the context in which they were established. Furthermore, we found that the rule-specific coding maintained in anticipation of stimuli may change with execution of the rule: representations in context-independent regions remain invariant from maintenance to execution stages, whereas rule representations in context-dependent regions do not generalize to execution stage. The identification of distinct frontoparietal systems with context-independent and context-dependent task rule representations, and the distinction between anticipatory and executive rule representations, provide new insights into the functional architecture of goal-directed behavior.
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[Correlation between the numbers of peripheral blood dendritic cells and the clinical manifestations in children with respiratory syncytial virus bronchiolitis].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 07-11-2013
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To detect the quantity of peripheral blood myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells (pDCs) in children with bronchiolitis infected by respiratory syncytial virus (RSV) and analyze the correlation with the severity of the disease.
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Inhibition of SIRT6 in prostate cancer reduces cell viability and increases sensitivity to chemotherapeutics.
Protein Cell
PUBLISHED: 06-20-2013
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SIRT6 is an important histone modifying protein that regulates DNA repair, telomere maintenance, energy metabolism, and target gene expression. Recently SIRT6 has been identified as a tumor suppressor and is down-regulated in certain cancer types, but not in other cancers. From deposited gene profiling studies we found that SIRT6 was overexpressed in prostate tumors, compared with normal or paratumor prostate tissues. Tissue micro-array studies confirmed the higher levels of SIRT6 in both prostate tumor tissues and prostate cancer cells than in their normal counterparts. Knockdown of SIRT6 in human prostate cancer cells led to sub-G1 phase arrest of cell cycle, increased apoptosis, elevated DNA damage level and decrease in BCL2 gene expression. Moreover, SIRT6-de-ficiency reduced cell viability and enhanced chemotherapeutics sensitivity. Taken together, this study provides the first evidence of SIRT6 overexpression in human prostate cancer, and SIRT6 regulation could be exploited for prostate cancer therapy.
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Isolation of acetoin-producing Bacillus strains from Japanese traditional food-natto.
Prep. Biochem. Biotechnol.
PUBLISHED: 06-08-2013
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In this study, Bacillus strains with an ability to produce acetoin were isolated from a Japanese traditional food, natto, on the basis of the Voges-Proskauer (VP) reaction, and strain SF4-3 was shown to be a predominant strain in acetoin production. Based on a variety of morphological, physiological, and biochemical characteristics as well as the nucleotide sequence analysis of 16S rDNA, the strain SF4-3 was identified as Bacillus subtilis. When it was incubated at 37°C with a speed of 180 rpm for 96 hr in the flasks, the maximum acetoin concentration was up to 33.90 g/L. The fermentation broths were determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) analyses; the results showed that the major metabolite was acetoin, and the purity could reach more than 95% without butanedione and 2,3-butanediol, which were usually produced together with acetoin in other strains. A novel aqueous two-phase system (ATPS) composed of hydrophilic solvents and inorganic salts was developed for the extraction of acetoin from fermentation broths. The ethanol and dipotassium hydrogen phosphate system could be used to extract acetoin from fermentation broths. The influences of phase composition on partition of acetoin were investigated. The maximum partition coefficient (9.68) and recovery (94.6%) of acetoin were obtained, when 25% (w/w) dipotassium hydrogen phosphate and 24% (w/w) ethanol were used.
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Chameleon Behavior of a Newly Synthesized Scandium Nitrilimine Derivative.
J. Am. Chem. Soc.
PUBLISHED: 05-23-2013
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The synthesis, structural characterization, and reactivity of the first example of a scandium -substituted nitrilimine are presented. This unique complex exhibits high thermal stability but shows a rich reactivity toward a variety of unsaturated substrates, including aldehyde, ketone, nitrile, and allene derivatives. The versatility of the complex was further highlighted by density functional theory mechanistic studies.
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[Influence of water fluoride exposure on sex hormone binding globulin and testosterone in adult male].
Wei Sheng Yan Jiu
PUBLISHED: 05-10-2013
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To explore the influence of water fluoride exposure on sex hormone binding globulin (SHBG) and testosterone in adult male.
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Nonlinear optical response and biological applications of a series of pyrimidine-based molecules for copper(II) ion probe.
Dalton Trans
PUBLISHED: 05-07-2013
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Biological metal detecting, small molecule probes bearing nonlinear optical (NLO) response provide powerful alternatives due to their favorable photophysical properties (e.g. excitation wavelength in the near-IR region), cell permeability (due to their size), and chemical structure flexibility. Here, we present a series of pyrimidine-based NLO biological metal probes, especially a novel copper specific one which taken into account of the small volume-scaled and low cost-scaled nonlinear optical response of TPP and TPP-Cu(2+) discussed in our present work. The photophysical properties of the probes were thoroughly investigated. (1)H NMR and theoretical computation prove the binding interaction between the probe and the copper ion, which supports the functions of the molecule as a fluorescence signaling unit showing strong fluorescence quenching upon copper metal ion binding. On the other hand, the two-photon absorption cross-section of the novel copper probe increased from 275 to 591 GM (?(ex) = 830 nm) after interacting with copper ion. It was further demonstrated that the NLO response for the copper(ii) ion probe could be used for biological copper detection in live cells.
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Protein-assisted fabrication of nano-reduced graphene oxide for combined in vivo photoacoustic imaging and photothermal therapy.
Biomaterials
PUBLISHED: 03-14-2013
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Theranostic agents are attracting a great deal of attention in personalized medicine. Here, we developed a protein-based, facile method for fabrication of nanosized, reduced graphene oxide (nano-rGO) with high stability and low cytotoxicity. We constructed highly integrated photoacoustic/ultrasonic dual-modality imaging and photothermal therapy platforms, and further demonstrated that the prepared nano-rGO can be used as ready-to-use theranostic agents for both photoacoustic imaging and photothermal therapy without further surface modification. Intravenous administration of nano-rGO in tumor-bearing mice showed rapid and significant photoacoustic signal enhancement in the tumor region, indicating its excellence for passive targeting and photoacoustic imaging. Meanwhile, using a continuous-wave near-infrared laser, cancer cells in vivo were efficiently ablated, due to the photothermal effect of nano-rGO. The results suggest that the nano-rGO with protein-assisted fabrication was well suited for photoacoustic imaging and photothermal therapy of tumor, which is promising for theranostic nanomedicine.
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Exfoliation of hexagonal boron nitride by molten hydroxides.
Adv. Mater. Weinheim
PUBLISHED: 02-22-2013
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Hexagonal boron nitride (h-BN) nanosheets are prepared by a novel and effective method, in which sodium hydroxide and potassium hydroxide molten salts are used to exfoliate h-BN to obtain nanosheets. BN nanoscrolls are also obtained. The as-prepared products can be readily dispersed in a wide range of solvents, including water and ethanol, and form stable dispersions.
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Effects of Nogo-A receptor antagonist on the regulation of the Wnt signaling pathway and neural cell proliferation in newborn rats with hypoxic ischemic encephalopathy.
Mol Med Rep
PUBLISHED: 02-16-2013
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Hypoxic ischemic encephalopathy is a serious condition due to inadequate oxygen supply to the brain. Regeneration of neural cells is a critical process for repairing the damaged brain. Nogo has been identified as an inhibitor of neurite outgrowth that is specific to the brain. In the present study, the Nogo-A receptor (NgR) antagonist NEP1-40 was used to study the effects of inhibition of NgR on the regeneration of neural cells and the related Wnt signaling pathway in newborn rats. The investigation focused on the transcription factors regulated in the Wnt signaling pathway during the repair process, together with the proliferation of neural cells. The results indicated that c-Jun and c-Myc were the main transcription factors involved in the Wnt signaling pathway, while neural cell proliferation in the subventricular zone was increased during this process.
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Changes of dendritic spine density and morphology in the superficial layers of the medial entorhinal cortex induced by extremely low-frequency magnetic field exposure.
PLoS ONE
PUBLISHED: 01-01-2013
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In the present study, we investigated the effects of chronic exposure (14 and 28 days) to a 0.5 mT 50 Hz extremely low-frequency magnetic field (ELM) on the dendritic spine density and shape in the superficial layers of the medial entorhinal cortex (MEC). We performed Golgi staining to reveal the dendritic spines of the principal neurons in rats. The results showed that ELM exposure induced a decrease in the spine density in the dendrites of stellate neurons and the basal dendrites of pyramidal neurons at both 14 days and 28 days, which was largely due to the loss of the thin and branched spines. The alteration in the density of mushroom and stubby spines post ELM exposure was cell-type specific. For the stellate neurons, ELM exposure slightly increased the density of stubby spines at 28 days, while it did not affect the density of mushroom spines at the same time. In the basal dendrites of pyramidal neurons, we observed a significant decrease in the mushroom spine density only at the later time point post ELM exposure, while the stubby spine density was reduced at 14 days and partially restored at 28 days post ELM exposure. ELM exposure-induced reduction in the spine density in the apical dendrites of pyramidal neurons was only observed at 28 days, reflecting the distinct vulnerability of spines in the apical and basal dendrites. Considering the changes in spine number and shape are involved in synaptic plasticity and the MEC is a part of neural network that is closely related to learning and memory, these findings may be helpful for explaining the ELM exposure-induced impairment in cognitive functions.
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Intermedin suppresses pressure overload cardiac hypertrophy through activation of autophagy.
PLoS ONE
PUBLISHED: 01-01-2013
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Left ventricular hypertrophy is a maladaptive response to pressure overload and an important risk factor for heart failure. Intermedin (IMD), a multi-functional peptide, plays important roles in cardiovascular protection. In this study, we revealed an autophagy-dependent mechanism involved in IMDs protection against cardiac remodeling and cardiomyocyte death in heart hypertrophy. We observed that transverse aortic contraction (TAC) induction, Ang II or ISO exposure induced remarkable increase in the expression of endogenous IMD and its receptor components, CRLR, RAMP1 and RAMP3, in mouse hearts and H9c2 cell cultures, respectively. Furthermore, the heart size, heart weight/body weight ratios, cardiomyocyte size and apoptosis, interstitial collagen, hypertrophic markers including ANP and BNP expression were also significantly increased, which were effectively suppressed by IMD supplementation. In addition, IMD induced capillary angiogenesis and improved functions in hypertrophic hearts. We further observed that IMD induced strong autophagy in hypertrophic hearts and cultured cells, which was paralleling with the decrease in cardiomyocyte size and apoptosis. Furthermore, an autophagy inhibitor, 3-MA, was used to block the IMD-augmented autophagy level, and then the protection of IMD on cardiomyocyte hypertrophy and apoptosis was almost abrogated. We also observed that IMD supplementation stirred intracellular cAMP production, and augmented the ERK1/2 phosphorylation induced by Ang II/ISO exposure in H9c2 cells. In addition, we inhibited PI3K, PKA and MAPK/ERK1/2 signaling pathways by using wortamannin, H89 and PD98059, respectively, in H9c2 cells co-incubating with both IMD and Ang II or ISO, and observed that these inhibitors effectively reduced IMD-augmented autophagy level, but only H89 and PD98059 pre-incubation abrogated the anti-apoptotic action of IMD. These results indicate that the endogenous IMD and its receptor complexes are induced in hypertrophic cardiomyocytes and proposed to play an important role in the pathogenesis of cardiac hypertrophy, and the autophagy stirred by IMD supplementation is involved in its protection against cardiomyocyte hypertrophy and apoptosis through the activation of both cAMP/PKA and MAPK/ERK1/2 pathways.
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Preparation and characterization of a lipoid adsorption material and its atrazine removal performance.
J Environ Sci (China)
PUBLISHED: 12-02-2011
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A novel adsorbent named lipoid adsorption material (LAM), with a hydrophobic nucleolus (triolein) and a hydrophilic membrane structure (polyamide), was synthesized to remove hydrophobic organic chemicals (HOCs) from solution. Triolein, a type of lipoid, was entrapped by the polyamide membrane through an interfacial polymerization reaction. The method of preparation and the structure of the LAM were investigated and subsequent experiments were conducted to determine the characteristics of atrazine (a type of HOC) removal from wastewater using LAM as the adsorbent. The results showed that LAM had a regular structure compared with the prepolymer, where compact particles were linked with each other and openings were present in the structure of the LAM in which the fat drops formed from triolein were entrapped. In contrast to the atrazine adsorption behavior of powdered activated carbon (PAC), LAM showed a persistent adsorption capacity for atrazine when initial concentrations of 0.57, 1.12, 8.31 and 19.01 mg/L were present, and the equilibrium time was 12 hr. Using an 8 mg/L initial concentration of atrazine as an indicator of HOCs in aqueous solution, experiments on the adsorption capacity of the LAM showed 69.3% removal within 6-12 hr contact time, which was close to the 75.5% removal of atrazine by PAC. Results indicated that LAM has two atrazine removal mechanisms, namely the bioaccumulation of atrazine by the nucleous material and physical adsorption to the LAM membrane. Bioaccumulation was the main removal mechanism.
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Platelet TGF-?1 contributions to plasma TGF-?1, cardiac fibrosis, and systolic dysfunction in a mouse model of pressure overload.
Blood
PUBLISHED: 12-01-2011
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Circulating platelets contain high concentrations of TGF-?1 in their ?-granules and release it on platelet adhesion/activation. We hypothesized that uncontrolled in vitro release of platelet TGF-?1 may confound measurement of plasma TGF-?1 in mice and that in vivo release and activation may contribute to cardiac pathology in response to constriction of the transverse aorta, which produces both high shear and cardiac pressure overload. Plasma TGF-?1 levels in blood collected from C57Bl/6 mice by the standard retro-bulbar technique were much higher than those obtained when prostaglandin E? was added to inhibit release or when blood was collected percutaneously from the left ventricle under ultrasound guidance. Even with optimal blood drawing, plasma TGF-?1 was lower in mice rendered profoundly thrombocytopenic or mice with selectively low levels of platelet TGF-?1 because of megakaryocyte-specific disruption of their TGF-?1 gene (Tgfb1(flox)). Tgfb1(flox) mice were also partially protected from developing cardiac hypertrophy, fibrosis, and systolic dysfunction in response to transverse aortic constriction. These studies demonstrate that plasma TGF-?1 levels can be assessed accurately, but it requires special precautions; that platelet TGF-?1 contributes to plasma levels of TGF-?1; and that platelet TGF-?1 contributes to the pathologic cardiac changes that occur in response to aortic constriction.
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Synthesis, crystal structures, photophysical properties, and bioimaging of living cells of bis-?-diketonate phenothiazine ligands and its cyclic dinuclear complexes.
Inorg Chem
PUBLISHED: 08-09-2011
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Two bis-?-diketones, RCOCH(2)CO-EPTZ-COCH(2)COR (EPTZ = 10-ethylphenothiazine; R = C(6)H(5) for H(2)L(1) and CF(3) for H(2)L(2)) and their cyclic dinuclear Zn(II), Cd(II), Ni(II), Mn(II), Cu(II), Co(II) complexes have been synthesized and fully characterized. Their crystal structures were determined by single crystal X-ray diffraction analysis. Their photophysical properties have been further investigated both experimentally and theoretically. The results revealed that significant enhancement of two-photon absorption cross section values were obtained for the cyclic dinuclear Zn(II) and Cd(II) complexes compared with their free ligands. Additionally, confocal microscopy and two-photon microscopy fluorescent imaging of MCF-7 cells labeled with two ligands and Zn(II) complexes reveal their potential applications as a biological fluorescent probe.
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Preservation of residual renal function with limited water removal in hemodialysis patients.
Ren Fail
PUBLISHED: 08-08-2011
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Residual renal function (RRF) is of paramount importance for hemodialysis (HD) adequacy, morbidity, and mortality. Some studies have shown that overhydration is beneficial for preservation of RRF, but it can also increase the probability of adverse events such as hypertension and heart failure in HD patients. To determine the optimal amount of dehydration, we performed HD with limited water removal in HD patients. Eighteen HD patients included in this self-controlled study underwent HD with limited water removal. Water removal volume was determined by a previous volume as follows. Total water removal volume was divided into levels: ?3.0, 3.0-9.0, and >9.0 L per week. Water removal was performed to obtain dry weight in the last dialysis, and was performed three times with a ratio of 1:1:2 and 2:2:3, respectively. Urine volume, endogenous creatinine clearance rate, Kt/V, hemoglobin, and serum albumin were recorded before and after the study at 3, 6, 9, and 12 months. The follow-up period was 12 months. Ten patients withdrew from the study because of adverse events including hypertension (n = 3), heart failure (n = 3), angina (n = 1), polycystic kidney rupture (n = 1), obvious edema (n = 1), and one patient had too much interdialytic weight gain to continue. As a result, we stopped this study after 1 month. Our data suggest that the preservation of RRF with limited water removal in HD patients must be interpreted with caution.
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Studies of the isomerization and photophysical properties of a novel 2,2:6,2-terpyridine-based ligand and its complexes.
Dalton Trans
PUBLISHED: 07-05-2011
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A novel 2,2:6,2-terpyridine-based ligand L and its complexes [ML(2)](ClO(4))(2)·CH(2)Cl(2) (M = Cd 1, Zn 2, Cu 4, Mn 5), [CoL(2)](ClO(4))(2)3, CdLI(2)6 and CdL(SCN)(2)7 were synthesized and fully characterized. The crystal structures of 1-6 were solved by single crystal X-ray diffraction analysis. The linear absorption and emission properties, and third-order nonlinear optical (NLO) properties of all the complexes were systematically investigated. The equilibrium of the trans- and cis- isomers of L was studied both experimentally and theoretically. The configurations and photophysical properties of the complexes display a large dependence on the choice of metal ions and anions.
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Remodeling of atrial ATP-sensitive K? channels in a model of salt-induced elevated blood pressure.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 07-01-2011
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Hypertension is associated with the development of atrial fibrillation; however, the electrophysiological consequences of this condition remain poorly understood. ATP-sensitive K(+) (K(ATP)) channels, which contribute to ventricular arrhythmias, are also expressed in the atria. We hypothesized that salt-induced elevated blood pressure (BP) leads to atrial K(ATP) channel activation and increased arrhythmia inducibility. Elevated BP was induced in mice with a high-salt diet (HS) for 4 wk. High-resolution optical mapping was used to measure atrial arrhythmia inducibility, effective refractory period (ERP), and action potential duration at 90% repolarization (APD(90)). Excised patch clamping was performed to quantify K(ATP) channel properties and density. K(ATP) channel protein expression was also evaluated. Atrial arrhythmia inducibility was 22% higher in HS hearts compared with control hearts. ERP and APD(90) were significantly shorter in the right atrial appendage and left atrial appendage of HS hearts compared with control hearts. Perfusion with 1 ?M glibenclamide or 300 ?M tolbutamide significantly decreased arrhythmia inducibility and prolonged APD(90) in HS hearts compared with untreated HS hearts. K(ATP) channel density was 156% higher in myocytes isolated from HS animals compared with control animals. Sulfonylurea receptor 1 protein expression was increased in the left atrial appendage and right atrial appendage of HS animals (415% and 372% of NS animals, respectively). In conclusion, K(ATP) channel activation provides a mechanistic link between salt-induced elevated BP and increased atrial arrhythmia inducibility. The findings of this study have important implications for the treatment and prevention of atrial arrhythmias in the setting of hypertensive heart disease and may lead to new therapeutic approaches.
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Photocontrollable J-aggregation of a diarylethene-phthalocyanine hybrid and its aggregation-stabilized photochromic behavior.
Langmuir
PUBLISHED: 06-13-2011
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The photocontrollable J-aggregation of a diarylethene-phthalocyanine hybrid (T-ZnPc) and its aggregation-stabilized photochromic behavior were investigated by various techniques. T-ZnPc initially exhibited slight J-aggregation tendency in solvents such as chloroform and toluene through conformational planarization effect, but formed much stronger J-aggregates upon the illumination of 254 nm UV light. In darkness, the UV-irradiated solutions gradually returned to their initial state. These phenomena can be explained by the pronounced change in molecular planarity accompanying the reversible isomerization of the diarylethene units of T-ZnPc. Besides, we have found that the thermal stability of the closed-ring diarylethene isomers in molecularly dispersed T-ZnPc is much poorer than that in aggregates. As long as the aggregates were broken, they converted to corresponding open-ring form instantly. This study provided an example of fully photocontrollable aggregation of phthalocyanines and paved a new way for improving the stability of the photochromic systems.
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Identification of potential serum biomarkers for Wilms tumor after excluding confounding effects of common systemic inflammatory factors.
Mol. Biol. Rep.
PUBLISHED: 05-10-2011
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Wilms tumor is the most common pediatric tumor of the kidney. Previous studies have identified several serum biomarkers for Wilms tumor; however, they lack sufficient specificity and may not adequately distinguish Wilms tumor from confounding conditions. To date, no specific protein biomarker has been confirmed for this pediatric tumor. To identify novel serum biomarkers for Wilms tumor, we used proteomic technologies to perform protein profiling of serum samples from pre-surgery and post-surgery patients with Wilms tumor and healthy controls. Some common systemic inflammatory factors were included to control for systemic inflammation. By comparing protein peaks among the three groups of sera, we identified two peaks (11,526 and 4,756 Da) showing significant differential expression not only between pre-surgery and control sera but also between pre-surgery and post-surgery sera. These two peaks were identified as serum amyloid A1 (SAA1) and apolipoprotein C-III (APO C-III). Western blot analysis confirmed that both proteins were expressed at higher levels in pre-surgery sera than in post-surgery and control sera. Using the method of leave-1-out for cross detection, we demonstrate that detection of these two candidate biomarkers had high sensitivity and specificity in discriminating pre-surgery sera from post-surgery and normal control sera. Taken together, these findings suggest that SAA1 and APO C-III are two potential biomarkers for Wilms tumor.
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Glucocorticoids facilitate astrocytic amyloid-? peptide deposition by increasing the expression of APP and BACE1 and decreasing the expression of amyloid-?-degrading proteases.
Endocrinology
PUBLISHED: 05-10-2011
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In most cases, the molecular mechanism underlying the pathogenesis of sporadic Alzheimers disease (AD) is unknown. Elevated basal cortisol levels in AD patients suggest that glucocorticoids (GC) may contribute to the development and/or maintenance of AD. Amyloid plaques are the hallmark of AD, and they are considered to play an early role in the AD process. However, little is known about how their formation is regulated by stress and GC. Astrocyte accumulation is one of the earliest neuropathological changes in AD. Here, we report that GC elevated amyloid-? (A?) production in primary cultures of astrocytes by increasing amyloid precursor protein (APP) and ?-site APP-cleaving enzyme 1 gene expression. Notably, GC administered to normal, middle-aged mice promoted the expression of APP and ?-site APP-cleaving enzyme 1 in astrocytes, as determined by double immunofluorescence. Additionally, confocal microscopy and ELISA revealed that GC markedly reduced A? degradation and clearance by astrocytes in vitro, indicating a decreased neuroprotective capacity of the astrocytes. This may have been due to the decrease of several A?-degrading proteases, such as insulin-degrading enzyme and matrix metalloproteinase-9. These effects occurred through the activation of GC receptors. Taken together, our results demonstrate that GC can enhance the production of A?, reduce its degradation in astrocytes, and provide a molecular mechanism linking stress factors to AD. Our study suggests that GC can facilitate AD pathogenesis and that reducing GC in the elderly and early AD patients would be beneficial.
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Phosphatase-resistant gap junctions inhibit pathological remodeling and prevent arrhythmias.
Circ. Res.
PUBLISHED: 04-28-2011
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Posttranslational phosphorylation of connexin43 (Cx43) has been proposed as a key regulatory event in normal cardiac gap junction expression and pathological gap junction remodeling. Nonetheless, the role of Cx43 phosphorylation in the context of the intact organism is poorly understood.
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The sarcoplasmic reticulum luminal thiol oxidase ERO1 regulates cardiomyocyte excitation-coupled calcium release and response to hemodynamic load.
FASEB J.
PUBLISHED: 04-20-2011
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Two related ER oxidation 1 (ERO1) proteins, ERO1? and ERO1?, dynamically regulate the redox environment in the mammalian endoplasmic reticulum (ER). Redox changes in cysteine residues on intralumenal loops of calcium release and reuptake channels have been implicated in altered calcium release and reuptake. These findings led us to hypothesize that altered ERO1 activity may affect cardiac functions that are dependent on intracellular calcium flux. We established mouse lines with loss of function insertion mutations in Ero1l and Ero1lb encoding ERO1? and ERO1?. The peak amplitude of calcium transients in homozygous Ero1? mutant adult cardiomyocytes was reduced to 42.0 ± 2.2% (n=10, P ? 0.01) of values recorded in wild-type cardiomyocytes. Decreased ERO1 activity blunted cardiomyocyte inotropic response to adrenergic stimulation and sensitized mice to adrenergic blockade. Whereas all 12 wild-type mice survived challenge with 4 mg/kg esmolol, 6 of 8 compound Ero1l and Ero1lb mutant mice succumbed to this level of ? adrenergic blockade (P ? 0.01). In addition, mice lacking ERO1? were partially protected against progressive heart failure in a transaortic constriction model [at 10 wk postprocedure, fractional shortening was 0.31 ± 0.02 in the mutant (n=20) vs. 0.23 ± 0.03 in the wild type (n=18); P ? 0.01]. These findings establish a role for ERO1 in calcium homeostasis and suggest that modifying the lumenal redox environment may affect the progression of heart failure.
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Enhanced inner-shell x-ray emission by femtosecond-laser irradiation of solid cone targets.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 04-18-2011
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The possibility of enhancing inner-shell x-ray emission, especially K? emission, by femtosecond-laser irradiation of solid cones instead of foils was investigated theoretically. In a model for hot electron (HE) transport and K? x-ray generation, K? emission from laser-irradiated solid cones and foils is investigated. As a complementarity to the model, the contributions from electric and magnetic fields generated by the HE current in solid cones and foils are discussed. The results indicate that the efficiency of HE energy conversion to K? photons is improved and the optimum HE temperature is increased.
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[Topological match method in 3D reconstruction of heart vessel].
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
PUBLISHED: 04-13-2011
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This paper presents a novel matching method of vessels in 3D reconstruction of heart vessel. The directed binary tree was used to describe the topological structure of heart vessel trees skeleton. Based on topological property and epipolar property, the branch-points and end-points of each branch level could be automatically matched along the direction of blood stream. Thereupon it is easy to couple the corresponding vessels segments of two angiograms projected in different directions. The 3D heart vessel tree was successfully reconstructed from clinic coronary angiograms, which validates the presented method.
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Mechanism of phase splitting in two coupled groups of suprachiasmatic-nucleus neurons.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 03-20-2011
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The phase-splitting behavior of coupled suprachiasmatic-nucleus neurons has been observed in many mammals, and its mechanism is still not completely understood. Based on our previous work [C. Gu, J. Wang, and Z. Liu, Phys. Rev. E 80, 030904(R) (2009)] on the free-running periods of neurons in the suprachiasmatic nucleus, we present here a modified Goodwin oscillator model to explain the mechanism of phase splitting. In contrast to the previous phase model, the modified Goodwin oscillator model contains the information on both the phase and amplitude and, thus, can show more features than the purely phase model, including all three behaviors of synchronization, phase splitting, and amplitude death and the distributed periodicity in the regions of synchronization and phase splitting, etc. An analytic phase model is extracted from the modified Goodwin oscillator model to explain the dependence of periodicity on the parameters. Moreover, both the modified Goodwin oscillator model and the analytic phase model show that the ensemble frequency can be enhanced or reduced by the time delay.
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A role for suppressed bone formation favoring catch-up fat in the pathophysiology of catch-up growth after food restriction.
Eur J Nutr
PUBLISHED: 01-27-2011
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Catch-up growth is always companied with later development of obesity and osteoporosis that are two interrelated clinical entities. However, the potential mechanism of the link between them during catch-up growth is unknown.
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Aggregation-induced emission enhancement of polycyclic aromatic alkaloid derivatives and the crucial role of excited-state proton-transfer.
Chem. Commun. (Camb.)
PUBLISHED: 01-17-2011
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Aggregation-induced emission enhancement (AIEE) phenomenon is observed in the polycyclic aromatic alkaloid derivatives due to the configuration changes in the excited state, which is attributed to intramolecular proton-transfer and the formation of a new structure of enol form.
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Arousal effects of orexin A on acute alcohol intoxication-induced coma in rats.
Neuropharmacology
PUBLISHED: 01-06-2011
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The key role of the hypothalamic neuropeptides orexins in maintenance and promotion of arousal has been well established in normal mammalian animals, but whether orexins exert arousal effects under pathological condition such as coma was little studied. In this study, a model of unconscious rats induced by acute alcohol intoxication was used to examine the effects of orexins through intracerebroventricular injection. The results revealed that either orexin A or orexin B induced decrease of duration of loss of right reflex in alcohol-induced unconscious rats. In the presence of the selective orexin receptor 1 antagonist SB 334867 and orexin receptor 2 antagonist TCS OX2 29, the excitatory action of orexin A was completely blocked. Our data further presented that orexin A also induced reduction of delta power in EEG in these rats. Single-unit recording experiment in vivo demonstrated that orexin A could evoke increase of firing activity of prefrontal cortex neurons in unconscious rats. This excitation was completely inhibited by an H(1) receptor antagonist, pyrilamine, whereas application of ?(1)-adrenoreceptor antagonist prazosin or 5-HT(2) selective receptor antagonist ritanserin partially attenuated the excitatory effects of orexin A on these neurons. Consistently, the results of EEG recordings showed that microinjection of pyrilamine, prazosin, or ritanserin suppressed reduction of delta power in EEG induced by orexin A on unconscious rats. Thus, these data suggest that orexins exert arousal effects on alcohol-induced unconscious rats by the promotion of cortical activity through activation of histaminergic, noradrenergic and serotonergic systems. This article is part of a Special Issue entitled Post-Traumatic Stress Disorder.
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Scandium terminal imido complex induced C-H bond selenation and formation of an Sc-Se bond.
Chem. Commun. (Camb.)
PUBLISHED: 11-11-2010
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The reaction between scandium terminal imido complexes and elemental selenium showed an unprecedented C-H bond selenation and the formation of an Sc-Se bond.
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Learning alters the tuning of functional magnetic resonance imaging patterns for visual forms.
J. Neurosci.
PUBLISHED: 10-22-2010
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Learning is thought to facilitate the recognition of objects by optimizing the tuning of visual neurons to behaviorally relevant features. However, the learning mechanisms that shape neural selectivity for visual forms in the human brain remain essentially unknown. Here, we combine behavioral and functional magnetic resonance imaging (fMRI) measurements to test the mechanisms that mediate enhanced behavioral sensitivity in the discrimination of visual forms after training. In particular, we used high-resolution fMRI and multivoxel pattern classification methods to investigate fine learning-dependent changes in neural preference for global forms. We measured the observers choices when discriminating between concentric and radial patterns presented in noise before and after training. Similarly, we measured the choices of a pattern classifier when predicting each stimulus from fMRI activity. Comparing the performance of human observers and classifiers demonstrated that learning alters the observers sensitivity to visual forms and the tuning of fMRI activation patterns in visual areas selective for task-relevant features. In particular, training on low-signal stimuli enhanced the amplitude but reduced the width of pattern-based tuning functions in higher dorsal and ventral visual areas. Thus, our findings suggest that learning of visual patterns is implemented by enhancing the response to the preferred stimulus category and reducing the response to nonpreferred stimuli in higher extrastriate visual cortex.
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Learning-dependent plasticity with and without training in the human brain.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-13-2010
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Long-term experience through development and evolution and shorter-term training in adulthood have both been suggested to contribute to the optimization of visual functions that mediate our ability to interpret complex scenes. However, the brain plasticity mechanisms that mediate the detection of objects in cluttered scenes remain largely unknown. Here, we combine behavioral and functional MRI (fMRI) measurements to investigate the human-brain mechanisms that mediate our ability to learn statistical regularities and detect targets in clutter. We show two different routes to visual learning in clutter with discrete brain plasticity signatures. Specifically, opportunistic learning of regularities typical in natural contours (i.e., collinearity) can occur simply through frequent exposure, generalize across untrained stimulus features, and shape processing in occipitotemporal regions implicated in the representation of global forms. In contrast, learning to integrate discontinuities (i.e., elements orthogonal to contour paths) requires task-specific training (bootstrap-based learning), is stimulus-dependent, and enhances processing in intraparietal regions implicated in attention-gated learning. We propose that long-term experience with statistical regularities may facilitate opportunistic learning of collinear contours, whereas learning to integrate discontinuities entails bootstrap-based training for the detection of contours in clutter. These findings provide insights in understanding how long-term experience and short-term training interact to shape the optimization of visual recognition processes.
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Percutaneous radiofrequency thermocoagulation for the treatment of different types of trigeminal neuralgia: evaluation of quality of life and outcomes.
J. Huazhong Univ. Sci. Technol. Med. Sci.
PUBLISHED: 06-17-2010
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Radiofrequency thermocoagulation (RFT) of the gasserian ganglion is a routine and effective technique for the treatment of classical trigeminal neuralgia (CTN). In this study we compared its efficacy in patients with CTN and atypically symptomatic or mixed trigeminal neuralgia (MTN). Fifty-seven patients were treated with RFT for trigeminal neuralgia from June 2006 to February 2009. Thirty patients had CTN, and 27 had MTN. Outcomes were measured by using the visual analog pain scale (VAS) and patients reports of quality of life (QOL), medication usage, and complications over a follow-up period of up to 3 years. Our results showed that the patients with MTN were younger, tended to have bilaterial involvement of the first division, and were unresponsive to treatment. All surgeries were completed smoothly. About 86.7% CTN patients and 48.1% MTN patients responded immediately to RFT. The VAS scores were significantly higher in the CTN group than in MTN group (P<0.05). Kaplan-Meier curves showed that 1-year, 2-year, and 3-year pain relief rates were 76.7%, 73.3%, and 73.3% in the CTN group and 46.6%, 41.4%, and 41.4% in the MTN group, respectively. The rates of pain relief for both groups leveled off at 2 years. Complications included numbness, dysesthesia, and anesthesia dolorosa. RFT did not cause any deaths and complications were low. The treatment was very effective for CTN and, to some degrees, effective for MTN. If numbness, dysesthesia, and anesthesia dolorosa are limited to the trigger area, QOL will be greatly improved.
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Characterization of OP9 as authentic mesenchymal stem cell line.
J Genet Genomics
PUBLISHED: 05-06-2010
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Mesenchymal stem cells (MSCs) are multipotent stem cells capable of differentiating into various cell types, including osteocytes, chondrocytes, adipocytes, myocytes, and tenocytes. However, the difficulty or failure in expanding the mouse MSCs in vitro greatly hampered important research in animal models. The OP9, a stromal cell line from mouse bone marrow, has hematopoietic supportive capacity. Here, we report that the OP9 has the immunophenotype (CD45(-), CD11b(-), FLK-1(-), CD31(-), CD34(-), CD44(+), CD29(+), Sca-1(+), CD86(-), and MHCII(-)) identical to canonical mouse MSCs. The expression of CD140a(+), CD140b(+), alpha-SMA(+) and Calponin(+) suggested the perivascular origin of OP9. Functionally, the OP9 had strong clonogenic ability and could be induced into osteocytes, chondrocytes and adipocytes. The lymphocyte transformation test (LTT) and mixed leukocyte reaction (MLR) showed that the OP9 could suppress T lymphocyte proliferation stimulated by nonspecific mitogens (PHA) or allogeneic lymphocytes (BALB/c T cells). Finally, the migration of OP9 could be efficiently induced by bFGF, IGF-1, IL-3, PDGF-BB, TGF-beta1 and TGF-beta3. In conclusion, the OP9 were bona fide MSCs, and such homogenous cell line will be helpful to delineate biological features of MSCs at the stem cell level.
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Common variants in 22 loci are associated with QRS duration and cardiac ventricular conduction.
Nona Sotoodehnia, Aaron Isaacs, Paul I W de Bakker, Marcus Dörr, Christopher Newton-Cheh, Ilja M Nolte, Pim van der Harst, Martina Müller, Mark Eijgelsheim, Alvaro Alonso, Andrew A Hicks, Sandosh Padmanabhan, Caroline Hayward, Albert Vernon Smith, Ozren Polašek, Steven Giovannone, Jingyuan Fu, Jared W Magnani, Kristin D Marciante, Arne Pfeufer, Sina A Gharib, Alexander Teumer, Man Li, Joshua C Bis, Fernando Rivadeneira, Thor Aspelund, Anna Köttgen, Toby Johnson, Kenneth Rice, Mark P S Sie, Ying A Wang, Norman Klopp, Christian Fuchsberger, Sarah H Wild, Irene Mateo Leach, Karol Estrada, Uwe Völker, Alan F Wright, Folkert W Asselbergs, Jiaxiang Qu, Aravinda Chakravarti, Moritz F Sinner, Jan A Kors, Astrid Petersmann, Tamara B Harris, Elsayed Z Soliman, Patricia B Munroe, Bruce M Psaty, Ben A Oostra, L Adrienne Cupples, Siegfried Perz, Rudolf A de Boer, André G Uitterlinden, Henry Völzke, Timothy D Spector, Fang-Yu Liu, Eric Boerwinkle, Anna F Dominiczak, Jerome I Rotter, Gé van Herpen, Daniel Levy, H-Erich Wichmann, Wiek H van Gilst, Jacqueline C M Witteman, Heyo K Kroemer, W H Linda Kao, Susan R Heckbert, Thomas Meitinger, Albert Hofman, Harry Campbell, Aaron R Folsom, Dirk J van Veldhuisen, Christine Schwienbacher, Christopher J O'Donnell, Claudia Beu Volpato, Mark J Caulfield, John M Connell, Lenore Launer, Xiaowen Lu, Lude Franke, Rudolf S N Fehrmann, Gerard te Meerman, Harry J M Groen, Rinse K Weersma, Leonard H van den Berg, Cisca Wijmenga, Roel A Ophoff, Gerjan Navis, Igor Rudan, Harold Snieder, James F Wilson, Peter P Pramstaller, David S Siscovick, Thomas J Wang, Vilmundur Gudnason, Cornelia M van Duijn, Stephan B Felix, Glenn I Fishman, Yalda Jamshidi, Bruno H Ch Stricker, Nilesh J Samani, Stefan Kääb, Dan E Arking.
Nat. Genet.
PUBLISHED: 05-03-2010
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The QRS interval, from the beginning of the Q wave to the end of the S wave on an electrocardiogram, reflects ventricular depolarization and conduction time and is a risk factor for mortality, sudden death and heart failure. We performed a genome-wide association meta-analysis in 40,407 individuals of European descent from 14 studies, with further genotyping in 7,170 additional Europeans, and we identified 22 loci associated with QRS duration (P < 5 × 10(-8)). These loci map in or near genes in pathways with established roles in ventricular conduction such as sodium channels, transcription factors and calcium-handling proteins, but also point to previously unidentified biologic processes, such as kinase inhibitors and genes related to tumorigenesis. We demonstrate that SCN10A, a candidate gene at the most significantly associated locus in this study, is expressed in the mouse ventricular conduction system, and treatment with a selective SCN10A blocker prolongs QRS duration. These findings extend our current knowledge of ventricular depolarization and conduction.
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Identification of novel serum biomarkers in child nephroblastoma using proteomics technology.
Mol. Biol. Rep.
PUBLISHED: 03-24-2010
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To screen and identify serum biomarkers for nephroblastoma in children using surface-enhanced laser desorption/ionization (SELDI) and other proteomics technologies. The surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS) was used to identify biomarkers in 100 children with nephroblastoma and 30 gender and age-matched normal healthy children. There were 30 cases of pre-operative patients and 70 cases of post-operative patients. Differentially expressed serum proteins were screened. The target proteins were then separated, purified, and analyzed by multidimensional high performance liquid chromatography (HPLC). The peptide mass fingerprints (PMFs) of each protein were obtained after scanning with LC-MS/MS (LTQ). The proteins were identified using SEQUEST and the biological functions and characterizations of these proteins were analyzed with bioinformatic methods. Two differential proteins (m/z 6455.5, 9190.8) were obtained. According to SEQUEST, the molecular masses of this two proteins indicated that they were apolipoprotein C-I and haptoglobin, respectively. Expressions of the two proteins were lower in the pre-surgery group compared with the post-surgery and control group (P<0.01). In contrast, the expression of this two proteins were higher in the early stage than in the advanced stage of nephroblastoma. Apolipoprotein C-I and haptoglobin may be used as potential biomarkers to predict the degree of malignancy, therapeutic outcomes, and prognosis of nephroblastoma in children.
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Detection and identification of potential biomarkers of breast cancer.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 01-14-2010
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Noninvasive and convenient biomarkers for early diagnosis of breast cancer remain an urgent need. The aim of this study was to discover and identify potential protein biomarkers specific for breast cancer.
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Two-photon absorption enhancement induced by aggregation with accurate photophysical data: spontaneous accumulation of dye in silica nanoparticles.
Chem. Commun. (Camb.)
PUBLISHED: 01-11-2010
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The accurate photophysical data of dye-concentrated nanoparticles have been measured by the strategy of constructing ethoxysilane hydrolysis-assisted nanomaterials, which give rise to a large enhancement in two-photon absorption.
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Detection and identification of potential biomarkers of non-small cell lung cancer.
Technol. Cancer Res. Treat.
PUBLISHED: 11-21-2009
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The aim of this study was to discover and identify potential protein biomarkers specific for non-small cell lung cancer (NSCLC). Two hundred and thirty five (235) Serum samples with 112 NSCLC and 123 controls were randomly divided into a training set and a blind testing set. Serum proteomic profiles were analyzed using surface-enhanced laser desorption/ionization time-of-flight mass spectroscopy (SELDI-TOF-MS). Candidate protein biomarkers were purified by high Performance Liquid Chromatography (HPLC) and identified by liquid chromatography tandem mass spectrometry (LC-MS/MS) and validated using ProteinChip immunoassays. A total of 3 peaks (m/z with 6628, 9191 and 11412 Da) were screened out by SVM to construct the classification model with the high discriminatory power in the training set. The sensitivity and specificity of the model were 96.56% and 94.79% respectively in the blind testing set. The candidate biomarker with m/z of 6628 Da was found down-regulated in NSCLC patients, and identified as apolipoprotein C-I. Another two candidate biomarkers (9191 and 11412 Da) were found up-regulated in serum of NSCLC patients and identified as haptoglobin alpha-1 chain and S100A4, respectively. We have identified a set of biomarkers that could discriminate NSCLC from non-cancer controls. An efficient strategy, including SELDI-TOF-MS analysis, HPLC purification, MALDI-TOF-MS trace and LC-MS/MS identification, has been proved successfully.
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The metal-insulator transition in the half-filled extended Hubbard model on a triangular lattice.
J Phys Condens Matter
PUBLISHED: 10-30-2009
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In this paper, we have investigated the metal-insulator transition (MIT) in a two-dimensional half-filled extended Hubbard model on an isotropic triangular lattice with a real space block renormalization group technique. It has been found that the MIT can be driven nontrivially by either the on-site interaction U or the nearest-neighbor one V, but with different critical exponents. Depending upon the values of V, the system could have one, two or three MIT critical points. Moreover, for the metallic regime, we have also studied the competition effect from the spin density wave and charge density wave phases by using a mean-field theory based upon Hartree-Fock approximations. Finally, the single-site entanglement is also calculated and its first derivative with respect to U shows a jump along the critical line of the MIT.
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A comparison of bounded diffusion models for choice in time controlled tasks.
J Math Psychol
PUBLISHED: 10-09-2009
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The Wiener diffusion model (WDM) for 2-alternative tasks assumes that sensory information is integrated over time. Recent neurophysiological studies have found neural correlates of this integration process in certain neuronal populations. This paper analyses the properties of the WDM with two different boundary conditions in decision making tasks in which the time of response is indicated by a cue. A dual reflecting boundary mechanism is proposed and its performance is compared with a well-established absorbing boundary in the cases of the WDM, the WDM with extensions, and the WDM with prior probability. The two types of boundary influence the dynamics of the model and introduce differential weighting of evidence. Comparisons with Ornstein-Uhlenbeck models are also done, and it is shown that the WDM with both types of boundaries achieves similar performance and produce similar fits to existing behavioural data. Further studies are proposed to distinguish which boundary mechanism is more consistent with experimental data.
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Cytotoxicity and mutagenicity of retinol with ultraviolet A irradiation in mouse lymphoma cells.
Toxicol In Vitro
PUBLISHED: 08-11-2009
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Vitamin A (all-trans-retinol; retinol) is an essential human nutrient and plays an important role in several biological functions. However, under certain circumstances, retinol treatment can cause free radical generation and induce oxidative stress. In this study, we investigated photocytotoxicity and photomutagenicity of retinol using L5178Y/Tk(+/-) mouse lymphoma cells concomitantly exposed to retinol and ultraviolet A (UVA) light. While the cells treated with retinol alone at the doses of 5 or 10microg/ml in the absence of light did not increase the mutant frequency (MF) in the Tk gene, the treatment of the cells with 1-4microg/ml retinol under UVA light (1.38mW/cm(2) for 30min) increased the MF in the Tk gene in a dose-responsive manner. To elucidate the underlying mechanism of action, we also examined the mutational types of the Tk mutants by determining their loss of heterozygosity (LOH) at four microsatellite loci spanning the entire chromosome 11 on which the Tk gene is located. The mutational spectrum for the retinol+UVA treatment was significantly different from those of the control and UVA alone. More than 93% of the mutants from retinol+UVA treatment lost heterozygosity at the Tk1 locus and the major type (58%) of mutations was LOHs extending to D11Mit42, an alternation involving approximately 6cM of the chromosome, whereas the main type of mutations in the control was non-LOH mutations. These results suggest that retinol is mutagenic when exposed to UVA in mouse lymphoma cells through a clastogenic mode-of-action.
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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.

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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.