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Find video protocols related to scientific articles indexed in Pubmed.
Expression of calcineurin in podocytes in response to endoplasmic reticulum stress in diabetic nephropathy.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 11-01-2014
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Objective To investigate the regulation of calcineurin (CaN) by endoplasmic reticulum stress(ERS)in podocytes in vitro and in vivo at the stage microalbuminuria in diabetic nehropathy(DN). Methods The urinary albumin excretions of C57BLKS/J(Lepr) db/db and db/m mice at the ages of 6,9,and 12 weeks were measured. The expressions of CaN and synaptopodin of these mice were observed. In immortalized mouse podocytes,the expression of podocyte CaN incubated with different concentrations of paltimate was quantitatively determined by real-time PCR. The changes of CaN incubated with paltimate with or without ursodeoxy-cholic acid (UDCA) were analyzed by confocal microscopy and Western blotting. Results As urine protein increased,the expression of CaN was enhanced and the expression of synaptopodin was reduced in early stage DN db/db mice potocytes.In immortalized mouse podocytes,as the concentrations of palmitate increased,CaN mRNA increased. By confocal microscopy,the fluorescence intensity of CaN increased in palmitate treatment group.After co-incubation with palmitate and UDCA,the fluorescence intensity decreased. The similar results were shown by Western blotting. Conclusion At the stage of microalbuminuria in DN,ERS in podocytes up-regulates the expression of CaN.
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The Endothelial Protective Properties of Essential Oil from Fructus Alpiniae zerumbet via the Akt/NOS-NO Signaling Pathway In Vitro.
Planta Med.
PUBLISHED: 10-28-2014
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Oxidized low-density lipoprotein has been demonstrated to induce vascular injury, at least partly, through the nitric oxide-dependent pathway. Our previous studies showed that the essential oil from Fructus Alpiniae zerumbet had a capacity of antioxidation to ameliorate endothelial function and vasodilatation on aortic rings ex vivo. The present study aims to confirm the hypothesis that Fructus Alpiniae zerumbet protects against oxidized low-density lipoprotein-induced endothelial dysfunction in human aortic endothelial cells, and the role nitric oxide synthase plays in the process. Human aortic endothelial cells were pretreated with one of three different doses of Fructus Alpiniae zerumbet (1, 2, or 4?µg/mL), simvastatin (10?µM), or vehicle,followed by coincubation with oxidized low-density lipoprotein (150?µg/mL), for designed time periods. Exposure to oxidized low-density lipoprotein resulted in cytotoxicity accompanied by mitochondrial membrane potential collapse, excessive reactive oxygen species generation, and a decrease of nitric oxide production. The upregulation of inducible nitric oxide synthase mRNA and protein expression was determined by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. Furthermore, oxidized low-density lipoprotein inhibited Akt phosphorylation and downregulated endothelial nitric oxide synthase and soluble guanylatecyclase in mRNA expression and the protein level. However, cytotoxicity and aberrant reactive oxygen species and nitric oxide generation caused by oxidized low-density lipoprotein could be significantly inhibited by Fructus Alpiniae zerumbet or Sim pretreatment. Results from this study confirmed that Fructus Alpiniae zerumbet could protect against oxidized low-density lipoprotein-induced endothelial dysfunction by antioxidation and modulating the Akt/nitric oxide synthase-nitric oxide signaling pathway.
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[Efficacy of 48-week tenofovir disoproxil fumarate therapy in patients who were unresponsive to nucleoside-analogue treatments].
Zhonghua Gan Zang Bing Za Zhi
PUBLISHED: 09-01-2014
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To evaluate the efficacy and safety of tenofovir disoproxil fumarate (TDF) in patients with chronic hepatitis B (CHB) after failure of nucleoside-analogues (NAs).
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CdS Nanoflake Arrays for Highly Efficient Light Trapping.
Adv. Mater. Weinheim
PUBLISHED: 08-28-2014
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CdS nanoflake arrays exhibit unprecedented light absorption capability, and they can serve as a scaffold to load thin organic absorbers for extraordinarily high light absorption. Resultantly, the hybrid solar cell consisting of NFAs and organic absorber yields a ten-time high short-circuit photocurrent compared to the counterpart device with a common planar structure.
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Double open-circuit voltage of three-dimensional ZnO/CdTe solar cells by a balancing depletion layer.
ACS Appl Mater Interfaces
PUBLISHED: 08-18-2014
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Three-dimensional (3D) heterojunction solar cells (HSCs) were fabricated by thermal deposition of a compact CdTe layer onto ZnO nanorods (NRs). Although the 3D architecture obviously improves the short-circuit current of HSCs, the open-circuit voltage is rather low, and this problem can be addressed by inserting an intermediate layer between ZnO NRs and the CdTe layer. On the basis of experimental and theoretical analyses, we found that the low open-circuit voltage mainly arose from the incomplete depletion layer and serious recombination of carriers at the CdTe/ZnO interface. The CdS intermediate layer can redistribute the depletion regions and eliminate the interface defects, thus remarkably improving the open-circuit voltage.
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Impaired Adiponectin Signaling Contributes to Disturbed Catabolism of Branched-Chain Amino Acids in Diabetic Mouse.
Diabetes
PUBLISHED: 07-30-2014
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The branched-chain amino acids (BCAA) accumulated in type 2 diabetes mellitus are independent contributors to insulin resistance. The activity of branched-chain ?-keto acid dehydrogenase (BCKD) complex, rate-limiting enzyme in BCAA catabolism, is reduced in diabetic states, which contributes to elevated BCAA concentrations. However, the mechanisms underlying decreased BCKD activity remain poorly understood. Here we demonstrate that mitochondrial phosphatase 2C (PP2Cm), a newly identified BCKD phosphatase which increases BCKD activity, was significantly down-regulated in ob/ob and type 2 diabetic mice. Interestingly, in adiponectin knockout (APN(-/-)) mice fed with high-fat-diet (HD), PP2Cm expression and BCKD activity were significantly decreased, whereas BCKD kinase (BDK) which inhibits BCKD activity was markedly increased. Concurrently, plasma BCAA and branched-chain ?-keto acids (BCKA) were significantly elevated. APN treatment markedly reverted PP2Cm, BDK, BCKD activity, BCAA and BCKA levels in HD-fed APN(-/-) and diabetic animals. Additionally, increased BCKD activity caused by APN administration was partially but significantly inhibited in PP2Cm knockout mice. Finally, APN-mediated up-regulation of PP2Cm expression and BCKD activity were abolished when adenosine monophosphate-activated protein kinase (AMPK) was inhibited. Collectively, we have provided the first direct evidence that APN is a novel regulator of PP2Cm and systematic BCAA levels, suggesting that targeting APN may be a pharmacological approach to ameliorating BCAA catabolism in the diabetic state.
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Differential prooxidative effects of the green tea polyphenol, (-)-epigallocatechin-3-gallate, in normal and oral cancer cells are related to differences in sirtuin 3 signaling.
Mol Nutr Food Res
PUBLISHED: 07-18-2014
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We have previously reported that the green tea catechin, (-)-epigallocatechin-3-gallate (EGCG), can induce oxidative stress in oral cancer cells but exerts antioxidant effects in normal cells. Here, we report that these differential prooxidative effects are associated with sirtuin 3 (SIRT3), an important mitochondrial redox modulator.
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A New Technique to Map the Lymphatic Distribution and Alignment of the Penis.
Anat Rec (Hoboken)
PUBLISHED: 06-29-2014
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The present study was to examine the distribution of lymphatic vessels in the penis of normal adult males, which could provide an anatomical basis for improvement of incisions in penile lengthening surgery, and may also help to prevent postoperative refractory edema. Thirteen normal adult male volunteers were recruited for this study. Contrast agent was injected subcutaneously in the foreskin of the penis, and after two minutes magnetic resonance lymphangiography (MRL) was performed. The acquired magnetic resonance images were analyzed to determine the changes in the number and diameter of lymphatic vessels in different parts of the penis. Maximum Intensity Projections (MIP) and Materialise's Interactive Medical Image Control System (MIMICS) were applied to analyze the overall distribution of lymphatic vessels in the penis. Magnetic Resonance Imaging (MRI) showed that the lymphatic vessels were in conspicuous contrast with surrounding tissues and could be clearly identified. Penile lymphatic vessels were clearly visible in the root of the penis. At the junction of the penis and the abdominal wall, all lymphatic vessels were found to be concentrated in the dorsal part of the penis. MIP two-dimensional reconstruction showed that the overall distribution of relatively large lymphatic vessels in the dorsal and ventral parts of the penis could be seen clearly on bilateral 45 degree position, but not inside the abdominal wall because some of lymphatic vessels were overlapped by other tissues in the abdomen. MIMICS three-dimensional reconstruction was able to reveal the overall spatial distribution of lymphatic vessels in the penis from any angle. The reconstruction results showed that there were 1-2 main lymphatic vessels on the root of dorsal penis, which coursed along the cavernous to the first physiological curvature of the penis. Lymphatic vessels merged on both sides of the ventral penis. At the root of the penis, lymphatic vessels gradually coursed to the dorsal surface of the penis and folded at the abdominal wall to the outside, and finally merged into the inguinal lymph nodes. The changes in distribution, number and diameter of the lymphatic vessels in the penis were observed by MRI. MIP and MIMICS reconstructions directly revealed the anatomical features of penile lymphatic vessels such as spatial distribution, overall alignment, and the relations to adjacent structures, drainage and reflux. The study will provide the anatomical basis for penile surgery, penile lymphatic reflux disorders caused by trauma or lymphatic vessels obstruction, and lymph node metastasis in penile cancer. This article is protected by copyright. All rights reserved.
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PIN1 promoter polymorphism (-842 G>C) contributes to a decreased risk of cancer: Evidence from meta-analysis.
Oncol Lett
PUBLISHED: 06-24-2014
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Peptidyl-prolylcis-trans isomerase NIMA-interacting 1 (encoded by the PIN1 gene) regulates the conformation of proline-directed phosphorylation sites and is important in the etiology of cancer. Since the identification of a functional polymorphism of PIN1, (-842 G>C; rs2233678), in the PIN1 promoter region, numerous studies have evaluated the association between the PIN1 promoter polymorphism (-842 G>C) and cancer risk. However, the available results are inconclusive. To derive a more precise estimation, a meta-analysis of seven previous case-control studies was performed, which included 4,524 cases exhibiting different tumor types and 4,561 control subjects. The published literature was retrieved from PubMed and EMBASE. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to evaluate the strength of the association. Overall, the results of the present study demonstrated that individuals carrying the variant C allele (G/C and C/C) were associated with a significantly decreased cancer risk (OR, 0.75; 95% CI, 0.62-0.90 for GC vs. GG; OR, 0.75; 95% CI, 0.64-0.88 for GC/CC vs. GG). In further stratified analyses, a decreased cancer risk was observed in the following subgroups: Breast and lung cancer patients, Asian individuals, and in studies with a sample size >500. The results indicated that the PIN1 promoter polymorphism (-842 G>C; rs2233678) contributes to a decreased risk of cancer via attenuating the transcriptional activity.
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An ultrathin, smooth, and low-loss Al-doped Ag film and its application as a transparent electrode in organic photovoltaics.
Adv. Mater. Weinheim
PUBLISHED: 05-17-2014
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An ultrathin, smooth, and low-loss Ag film without a wetting layer is achieved by co-depositing a small amount of Al into Ag. The film can be as thin as 6 nm, with a roughness below 1 nm and excellent mechanical flexibility. Organic photovoltaics that use these thin films as transparent electrode show superior efficiency to their indium tin oxide (ITO) counterparts because of improved photon management.
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TXNIP mediates NLRP3 inflammasome activation in cardiac microvascular endothelial cells as a novel mechanism in myocardial ischemia/reperfusion injury.
Basic Res. Cardiol.
PUBLISHED: 05-07-2014
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NLRP3 inflammasome is necessary for initiating acute sterile inflammation. Recent studies have demonstrated that NLRP3 inflammasome is up-regulated and mediates myocardial ischemia/reperfusion (MI/R) injury. However, the signaling pathways that lead to the activation of NLRP3 inflammasome by MI/R injury have not been fully elucidated. C57BL/6J mice were subjected to 30 min ischemia and 3 or 24 h reperfusion. The ischemic heart exhibited enhanced inflammasome activation as evidenced by increased NLRP3 expression and caspase-1 activity and increased IL-1? and IL-18 production. Intramyocardial NLRP3 siRNA injection or an intraperitoneal injection of BAY 11-7028, an inflammasome inhibitor, attenuated macrophage and neutrophil infiltration and decreased MI/R injury, as measured by cardiomyocyte apoptosis and infarct size. The ischemic heart also exhibited enhanced interaction between Txnip and NLRP3, which has been shown to be a mechanism for activating NLRP3. Intramyocardial Txnip siRNA injection also decreased infarct size and NLRP3 activation. In vitro experiments revealed that NLRP3 was expressed in cardiac microvascular endothelial cells (CMECs), but was hardly expressed in cardiomyocytes. Simulated ischemia/reperfusion (SI/R) stimulated NLRP3 inflammasome activation in CMECs, but not in cardiomyocytes. Moreover, CMECs subjected to SI/R injury increased interactions between Txnip and NLRP3. Txnip siRNA diminished NLRP3 inflammasome activation and SI/R-induced injury, as measured by LDH release and caspase-3 activity in CMECs. ROS scavenger dissociated TXNIP from NLRP3 and inhibited the activation of NLRP3 inflammasome in the CMECs. For the first time, we demonstrated that TXNIP-mediated NLRP3 inflammasome activation in CMECs was a novel mechanism of MI/R injury. Interventions that block Txnip/NLRP3 signaling to inhibit the activation of NLRP3 inflammasomes may be novel therapies for mitigating MI/R injury.
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Adiponectin regulates SR Ca(2+) cycling following ischemia/reperfusion via sphingosine 1-phosphate-CaMKII signaling in mice.
J. Mol. Cell. Cardiol.
PUBLISHED: 04-15-2014
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The adipocyte-secreted hormone adiponectin (APN) exerts protective effects on the heart under stress conditions. Recent studies have demonstrated that APN induces a marked Ca(2+) influx in skeletal muscle. However, whether APN modulates [Ca(2+)]i activity, especially [Ca(2+)]i transients in cardiomyocytes, is still unknown. This study was designed to determine whether APN modulates [Ca(2+)]i transients in cardiomyocytes. Adult male wild-type (WT) and APN knockout (APN KO) mice were subjected to myocardial ischemia/reperfusion (I/R, 30min/30min) injury. CaMKII-PLB phosphorylation and SR Ca(2+)-ATPase (SERCA2) activity were downregulated in I/R hearts of WT mice and further decreased in those of APN KO mice. Both the globular domain of APN and full-length APN significantly reversed the decrease in CaMKII-PLB phosphorylation and SERCA2 activity in WT and APN KO mice. Interestingly, compared with WT littermates, single myocytes isolated from APN KO mice had remarkably decreased [Ca(2+)]i transients, cell shortening, and a prolonged Ca(2+) decay rate. Further examination revealed that APN enhances SERCA2 activity via CaMKII-PLB signaling. In in vivo and in vitro experiments, both APN receptor 1/2 and S1P were necessary for the APN-stimulated CaMKII-PLB-SERCA2 activation. In addition, S1P activated CaMKII-PLB signaling in neonatal cardiomyocytes in a dose dependent manner and improved [Ca(2+)]i transients in APN KO myocytes via the S1P receptor (S1PR1/3). Further in vivo experiments revealed that pharmacological inhibition of S1PR1/3 and SERCA2 siRNA suppressed APN-mediated cardioprotection during I/R. These data demonstrate that S1P is a novel regulator of SERCA2 that activates CaMKII-PLB signaling and mediates APN-induced cardioprotection.
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Bioconversion of natural gas to liquid fuel: opportunities and challenges.
Biotechnol. Adv.
PUBLISHED: 03-29-2014
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Natural gas is a mixture of low molecular weight hydrocarbon gases that can be generated from either fossil or anthropogenic resources. Although natural gas is used as a transportation fuel, constraints in storage, relatively low energy content (MJ/L), and delivery have limited widespread adoption. Advanced utilization of natural gas has been explored for biofuel production by microorganisms. In recent years, the aerobic bioconversion of natural gas (or primarily the methane content of natural gas) into liquid fuels (Bio-GTL) by biocatalysts (methanotrophs) has gained increasing attention as a promising alternative for drop-in biofuel production. Methanotrophic bacteria are capable of converting methane into microbial lipids, which can in turn be converted into renewable diesel via a hydrotreating process. In this paper, biodiversity, catalytic properties and key enzymes and pathways of these microbes are summarized. Bioprocess technologies are discussed based upon existing literature, including cultivation conditions, fermentation modes, bioreactor design, and lipid extraction and upgrading. This review also outlines the potential of Bio-GTL using methane as an alternative carbon source as well as the major challenges and future research needs of microbial lipid accumulation derived from methane, key performance index, and techno-economic analysis. An analysis of raw material costs suggests that methane-derived diesel fuel has the potential to be competitive with petroleum-derived diesel.
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Hypoglycemic and anti-depressant effects of Zuogui Jiangtang Jieyu formulation in a model of unpredictable chronic mild stress in rats with diabetes mellitus.
Exp Ther Med
PUBLISHED: 03-28-2014
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This study aimed to investigate the hypoglycemic, lipid-lowering and antidepressant effects of Zuogui Jiangtang Jieyu formulation (ZGJTJY) in a model of unpredictable chronic mild stress (UCMS) in rats with diabetes mellitus (DM; the UCMS-DM model). Sixty rats were randomly divided into blank control, vehicle (model plus vehicle), positive control (model plus metformin and fluoxetine), and high, medium and low dose ZGJTJY (model plus high, medium and low doses of ZGJTJY, respectively) groups. Following establishment of DM by a high-fat diet with intraperitoneal injection of streptozotocin (38 mg/kg), the depression model was established by application of UCMS for 28 days. The behavioral scores of the rats were detected in an open field test and Morris water maze test. The levels of blood glucose, glycosylated hemoglobin (HbA1c) and blood lipids were assayed. The total scores of the open field test and the space exploration times (SETs) in the Morris water maze test were significantly lower and the escape latency (EL) times in the Morris water maze test were significantly longer in the vehicle group compared with those in the blank control group. In addition, in the vehicle group, the levels of blood glucose, HbA1c, total cholesterol (TC), triglycerides (TGs) and low-density lipoprotein cholesterol (LDL-C) were significantly higher and the levels of high-density lipoprotein cholesterol (HDL-C) were significantly lower compared with those in the blank control group. The high dose of ZGJTJY decreased the locomotor activity levels in the open field test, the EL times of the model on day 4, the SETs in the Morris water maze test and the HDL-C levels, and reduced the blood glucose, HbA1c, TC, TG and LDL-C levels compared with those in the model group. Thus, ZGJTJY is a potential candidate for the prevention and treatment of the comorbidity of depression with DM.
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Prenylated benzoylphloroglucinols and xanthones from the leaves of Garcinia oblongifolia with antienteroviral activity.
J. Nat. Prod.
PUBLISHED: 03-28-2014
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An acetone extract of the leaves of Garcinia oblongifolia showed antiviral activity against enterovirus 71 (EV71) using a cytopathic effect inhibition assay. Bioassay-guided fractionation yielded 12 new prenylated benzoylphloroglucinols, oblongifolins J-U (1-12), and five known compounds. The structures of 1-12 were elucidated by spectroscopic analysis including 1D- and 2D-NMR and mass spectrometry methods. The absolute configurations were determined by a combination of a Mosher ester procedure carried out in NMR tubes and ECD calculations. Compared to ribavirin (IC50 253.1 ?M), compounds 1, 4, and 13 exhibited significant anti-EV71 activity in vitro, with IC50 values of 31.1, 16.1, and 12.2 ?M, respectively. In addition, the selectivity indices of these compounds were 1.5, 2.4, and 3.0 in African green monkey kidney (Vero) cells, respectively.
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Resting state fMRI feature-based cerebral glioma grading by support vector machine.
Int J Comput Assist Radiol Surg
PUBLISHED: 03-21-2014
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PURPOSE : Tumor grading plays an essential role in the optimal selection of solid tumor treatment. Noninvasive methods are needed for clinical grading of tumors. This study aimed to extract parameters of resting state blood oxygenation level-dependent functional magnetic resonance imaging (RS-fMRI) in the region of glioma and use the extracted features for tumor grading. METHODS : Tumor segmentation was performed with both conventional MRI and RS-fMRI. Four typical parameters, signal intensity difference ratio, signal intensity correlation (SIC), fractional amplitude of low-frequency fluctuation (fALFF) and regional homogeneity (ReHo), were defined to analyze tumor regions. Mann-Whitney [Formula: see text] test was employed to identify statistical difference of these four parameters between low-grade glioma (LGG) and high-grade glioma (HGG), respectively. Support vector machine (SVM) was employed to assess the diagnostic contributions of these parameters. RESULTS : Compared with LGG, HGG had more complex anatomical morphology and BOLD-fMRI features in the tumor region. SIC [Formula: see text], fALFF ([Formula: see text]) and ReHo ([Formula: see text]) were selected as features for classification according to the test [Formula: see text] value. The accuracy, sensitivity and specificity of SVM classification were better than 80, where SIC had the best classification accuracy (89). CONCLUSION : Parameters of RS-fMRI are effective to classify the tumor grade in glioma cases. The results indicate that this technique has clinical potential to serve as a complementary diagnostic tool.
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Mitochondrial translocation of Nur77 induced by ROS contributed to cardiomyocyte apoptosis in metabolic syndrome.
Biochem. Biophys. Res. Commun.
PUBLISHED: 03-13-2014
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Metabolic syndrome is a major risk factor for cardiovascular diseases, and increased cardiomyocyte apoptosis which contributes to cardiac dysfunction after myocardial ischemia/reperfusion (MI/R) injury. Nur77, a nuclear orphan receptor, is involved in such various cellular events as apoptosis, proliferation, and glucose and lipid metabolism in several cell types. Apoptosis is positively correlated with mitochondrial translocation of Nur77 in the cancer cells. However, the roles of Nur77 on cardiac myocytes in patients with metabolic syndrome remain unclear. The objective of this study was to determine whether Nur77 may contribute to cardiac apoptosis in patients with metabolic syndrome after I/R injury, and, if so, to identify the underlying molecular mechanisms responsible. We used leptin-deficient (ob/ob) mice to make metabolic syndrome models. In this report, we observed that, accompanied by the substantial decline in apoptosis inducer Nur77, MI/R induced cardiac dysfunction was manifested as cardiomyopathy and increased ROS. Using the neonatal rat cardiac myocytes cultured in a high-glucose and high-fat medium, we found that excessive H2O2 led to the significant alteration in mitochondrial membrane potential and translocation of Nur77 from the nucleus to the mitochondria. However, inhibition of the relocation of Nur77 to mitochondria via Cyclosporin A reversed the changes in membrane potential mediated by H2O2 and reduced myocardial cell injury. Therefore, these data provide a potential underlying mechanism for cardiac dysfunction in metabolic syndrome and the suppression of Nur77 translocation may provide an effective approach to reduce cardiac injury in the process.
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Performance and techno-economic assessment of several solid-liquid separation technologies for processing dilute-acid pretreated corn stover.
Bioresour. Technol.
PUBLISHED: 03-06-2014
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Solid-liquid separation of pretreated lignocellulosic biomass slurries is a critical unit operation employed in several different processes for production of fuels and chemicals. An effective separation process achieves good recovery of solute (sugars) and efficient dewatering of the biomass slurry. Dilute acid pretreated corn stover slurries were subjected to pressure and vacuum filtration and basket centrifugation to evaluate the technical and economic merits of these technologies. Experimental performance results were used to perform detailed process simulations and economic analysis using a 2000 tonne/day biorefinery model to determine differences between the various filtration methods and their process settings. The filtration processes were able to successfully separate pretreated slurries into liquor and solid fractions with estimated sugar recoveries of at least 95% using a cake washing process. A continuous vacuum belt filter produced the most favorable process economics.
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Increased myocardial ischemia-reperfusion injury in renal failure involves cardiac adiponectin signal deficiency.
Am. J. Physiol. Endocrinol. Metab.
PUBLISHED: 03-04-2014
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Plasma levels of adiponectin (APN) are significantly increased in patients with renal dysfunction and are inversely related to the risk of cardiovascular mortality. The present study was designed to determine the role of APN in myocardial ischemia-reperfusion (MI/R) injury in mice with renal failure and delineate the underlying mechanisms. Renal failure was induced by subtotal nephrectomy (SN). Human recombinant globular domain of adiponectin (gAd) or full-length adiponectin (fAd) was administered via intraperitoneal injection once daily for 7 consecutive days after SN, and in vivo MI/R was introduced 3 wk later. Both plasma and urinary levels of APN increased significantly in SN mice. Compared with sham-operated mice, cardiac function was significantly depressed, and myocardial infarct size and apoptosis increased in SN mice following MI/R. The aggravated MI/R injury was further intensified in APN-knockout mice and markedly ameliorated by treatment with gAd but not fAd. Moreover, SN increased myocardial NO metabolites, superoxide, and their cytotoxic reaction product peroxynitrite, upregulated inducible NO synthase expression, and decreased endothelial NOS phosphorylation. In addition, SN mice also exhibited reduced APN receptor-1 (AdipoR1) expression and AMPK activation. All these changes were further amplified in the absence of APN but reversed by gAd treatment. The present study demonstrates that renal dysfunction increases cardiac susceptibility to ischemic-reperfusion injury, which is associated with downregulated APN/AdipoR1/AMPK signaling and increased oxidative/nitrative stress in local myocardium, and provides the first evidence for the protective role of exogenous supplement of gAd on MI/R outcomes in renal failure.
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All-optical scanhead for ultrasound and photoacoustic imaging-Imaging mode switching by dichroic filtering.
Photoacoustics
PUBLISHED: 03-01-2014
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Ultrasound (US) and photoacoustic (PA) multimodality imaging has the advantage of combining good acoustic resolution with high optical contrast. The use of an all-optical scanhead for both imaging modalities can simplify integration of the two systems and miniaturize the imaging scanhead. Herein we propose and demonstrate an all-optical US/PA scanhead using a thin plate for optoacoustic generation in US imaging, a polymer microring resonator for acoustic detection, and a dichroic filter to switch between the two imaging modes by changing the laser wavelength. A synthetic-aperture focusing technique is used to improve the resolution and contrast. Phantom images demonstrate the feasibility of this design, and show that axial and lateral resolutions of 125 ?m and 2.52°, respectively, are possible.
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Ethylene-forming enzyme and bioethylene production.
Biotechnol Biofuels
PUBLISHED: 02-13-2014
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Worldwide, ethylene is the most produced organic compound. It serves as a building block for a wide variety of plastics, textiles, and chemicals, and a process has been developed for its conversion into liquid transportation fuels. Currently, commercial ethylene production involves steam cracking of fossil fuels, and is the highest CO2-emitting process in the chemical industry. Therefore, there is great interest in developing technology for ethylene production from renewable resources including CO2 and biomass. Ethylene is produced naturally by plants and some microbes that live with plants. One of the metabolic pathways used by microbes is via an ethylene-forming enzyme (EFE), which uses ?-ketoglutarate and arginine as substrates. EFE is a promising biotechnology target because the expression of a single gene is sufficient for ethylene production in the absence of toxic intermediates. Here we present the first comprehensive review and analysis of EFE, including its discovery, sequence diversity, reaction mechanism, predicted involvement in diverse metabolic modes, heterologous expression, and requirements for harvesting of bioethylene. A number of knowledge gaps and factors that limit ethylene productivity are identified, as well as strategies that could guide future research directions.
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The key features of percutaneous coronary intervention with chronic total obstruction lesion of right coronary artery.
Ther Adv Cardiovasc Dis
PUBLISHED: 01-17-2014
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We summarize recent research on percutaneous coronary intervention of chronic total occlusion of the right coronary artery. We then explain the method and technology of forward and backward revascularization in chronic total occlusion of the right coronary artery. Finally, we emphasize the monitoring methods and key treating measures for better prognosis of the patients.
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Disturbed small-world networks and neurocognitive function in frontal lobe low-grade glioma patients.
PLoS ONE
PUBLISHED: 01-01-2014
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Brain tumor patients often associated with losses of the small-world configuration and neurocognitive functions before operations. However, few studies were performed on the impairments of frontal lobe low-grade gliomas (LGG) after tumor resection using small-world network features.
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Effect of chronic pretreatment of angiotensin-converting receptor blocker on no-reflow phenomenon in patients with acute myocardial infarction undergoing percutaneous coronary intervention.
Cardiovasc Ther
PUBLISHED: 11-05-2013
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Angiotensin receptor blockers (ARBs) exert favorable effects on the vascular system, which are not directly related to hypertension lowering function. The no-reflow phenomenon determines the prognosis in patients after acute myocardial infarction (AMI). Early ARB treatment has many beneficial effects on the prognosis after AMI. In this study, we tested the hypothesis that ARB treatment before admission would have beneficial effects on the development of the no-reflow phenomenon after infarction.
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Effects of switching to lower sulfur marine fuel oil on air quality in the San Francisco Bay area.
Environ. Sci. Technol.
PUBLISHED: 08-27-2013
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Ocean-going vessels burning high-sulfur heavy fuel oil are an important source of air pollutants, such as sulfur dioxide and particulate matter. Beginning in July 2009, an emission control area was put into effect at ports and along the California coastline, requiring use of lower sulfur fuels in place of heavy fuel oil in main engines of ships. To assess impacts of the fuel changes on air quality at the Port of Oakland and in the surrounding San Francisco Bay area, we analyzed speciated fine particle concentration data from four urban sites and two more remote sites. Measured changes in concentrations of vanadium, a specific marker for heavy fuel oil combustion, are related to overall changes in aerosol emissions from ships. We found a substantial reduction in vanadium concentrations after the fuel change and a 28-72% decrease in SO2 concentrations, with the SO2 decrease varying depending on proximity to shipping lanes. We estimate that the changes in ship fuel reduced ambient PM2.5 mass concentrations at urban sites in the Bay area by about 3.1 ± 0.6% or 0.28 ± 0.05 ?g/m(3). The largest contributing factor to lower PM mass concentrations was reductions in particulate sulfate. Absolute sulfate reductions were fairly consistent across sites, whereas trace metal reductions were largest at a monitoring site in West Oakland near the port.
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Ultraviolet imprinting and aligned ink-jet printing for multilayer patterning of electro-optic polymer modulators.
Opt Lett
PUBLISHED: 08-14-2013
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The present work demonstrates an electro-optic polymer-based Mach-Zehnder (MZ) modulator fabricated utilizing advanced ultraviolet (UV) imprinting and aligned ink-jet printing technologies for patterning and layer deposition. The bottom electrode layer is designed and directly ink-jet printed on the substrate to form the patterned layer. The waveguide structure is formed into a bottom cladding polymer using a transparent flexible mold-based UV imprinting method. All other layers can be ink-jet printed. The top electrode is aligned and printed over the MZ arm. The modulator demonstrates a V-pi of 8 V at 3 kHz. This technology shows great potential in minimizing the fabrication complexity and roll-to-roll compatibility for manufacturing low cost, lightweight, and conformal modulators at high throughput.
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Notch1 cardioprotection in myocardial ischemia/reperfusion involves reduction of oxidative/nitrative stress.
Basic Res. Cardiol.
PUBLISHED: 06-13-2013
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Oxidative/nitrative stress plays an important role in myocardial ischemia/reperfusion (MI/R) injury. Notch1 participates in the regulation of cardiogenesis and cardiac response to hypertrophic stress, but the function of Notch1 signaling in MI/R has not been explored. This study aims to determine the role of Notch1 in MI/R, and investigate whether Notch1 confers cardioprotection. Notch1 specific small interfering RNA (siRNA, 20 ?g) or Jagged1 (a Notch ligand, 12 ?g) was delivered through intramyocardial injection. 48 h after injection, mice were subjected to 30 min of myocardial ischemia followed by 3 h (for cell apoptosis and oxidative/nitrative stress), 24 h (for infarct size and cardiac function), or 2 weeks (for cardiac fibrosis and function) of reperfusion. Cardiac-specific Notch1 knockdown resulted in significantly aggravated I/R injury, as evidenced by enlarged infarct size, depressed cardiac function, increased myocardial apoptosis and cardiac fibrosis. Downregulation of Notch1 increased expression of inducible NO synthase (iNOS) and gp(91phox), enhanced the production of NO metabolites and superoxide, as well as their cytotoxic reaction product peroxynitrite. Moreover, Notch1 blockade also reduced phosphorylation of endothelial NO synthase (eNOS) and Akt, and increased expression of PTEN, a key phosphatase involved in the regulation of Akt phosphorylation. In addition, activation of Notch1 by Jagged1 or administration of peroxynitrite scavenger reduced production of peroxynitrite and attenuated MI/R injury. These data indicate that Notch1 signaling protects against MI/R injury partly though PTEN/Akt mediated anti-oxidative and anti-nitrative effects.
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Apelin protects sarcoplasmic reticulum function and cardiac performance in ischaemia-reperfusion by attenuating oxidation of sarcoplasmic reticulum Ca2+-ATPase and ryanodine receptor.
Cardiovasc. Res.
PUBLISHED: 06-13-2013
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Apelin, an endogenous cytokine, has a number of biological effects on the cardiovascular system, including a cardioprotective effect and calcium modulation. Because the intracellular calcium abnormality is considered to play an important role in cardiac dysfunction induced by ischaemia-reperfusion (I/R), the aim of this study was to examine the effects of apelin-13 on I/R-induced changes in cardiac performance and sarcoplasmic reticulum (SR) function.
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The role of the mitochondrial oxidative stress in the cytotoxic effects of the green tea catechin, (-)-epigallocatechin-3-gallate, in oral cells.
Mol Nutr Food Res
PUBLISHED: 06-12-2013
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The tea catechin, (-)-epigallocatechin-3-gallate (EGCG), has potential cancer preventive effects. The prooxidant activity of EGCG may play a role in these effects.
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Comparison of different mechanical refining technologies on the enzymatic digestibility of low severity acid pretreated corn stover.
Bioresour. Technol.
PUBLISHED: 05-13-2013
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The effect of mechanical refining on the enzymatic digestibility of pretreated corn stover (PCS) was investigated. Low severity, dilute sulfuric acid PCS was subjected to mechanical refining using a bench-scale food processor blender, a PFI mill, a 12-inch laboratory disk refiner, and a 25 mm co-rotating twin-screw extruder. Glucose yields from enzymatic hydrolysis were improved by 10-15% after blending and disk refining, while PFI refining and twin-screw extrusion showed a glucose yield improvement of 16-20%. A pilot scale refining test using a Szego mill was performed and showed approximately 10% improvements in biomass digestibility. This suggests the possibility to scale up a mechanical refining technique to obtain similar enzymatic digestibility glucose yield enhancement as achieved by PFI milling and extrusion technologies. Proposed mechanisms of each mechanical refining technology are presented and reasons for improvements in biomass digestibility are discussed in this paper.
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Modified emulsion solvent evaporation method for fabricating core-shell microspheres.
Int J Pharm
PUBLISHED: 04-08-2013
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Solvent evaporation/extraction method is widely used for core-shell microspheres fabrication. However, the solvent evaporation rate, as an essential factor for polymers phase separation, is difficult to control which results in failure of complete phase separation between polymers. At the present study, the selective dissolution technique was used to improve the phase separation, and successfully fabricate core-shell microspheres for controlled delivery of drug with reduced initial burst release. The core-shell microspheres were prepared with poly(l-lactic-co-glycolic acid) (PLGA) and poly(l-lactic acid) (PLLA), and aspirin was used as model drug. Ethyl acetate (EtAc) was applied to ameliorate the phase separation during the preparation process. The ratio of dichloromethane (DCM)/EtAc seriously affected the distribution of polymer molecules and the formation of the core-shell structure. The internal morphology of the microspheres varied depending on the amount of EtAc. Core-shell structure with a dense core of PLLA and a shell of PLGA was well formed when 2 ml EtAc was used. The differential scanning calorimeters (DSC) results showed two distinct melting points which confirmed a completely polymer phased separation occurred. These microspheres showed sustained release of aspirin for at least 456 h with a little burst release (3.49%).
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Stress-induced growth-differentiation factor 15 plays an intriguing role in cardiovascular diseases.
Chin. Med. J.
PUBLISHED: 04-06-2013
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To provide an overview of the current knowledge of growth-differentiation factor 15 (GDF-15) in heart disease.
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Strain estimation in elastography using scale-invariant keypoints tracking.
IEEE Trans Ultrason Ferroelectr Freq Control
PUBLISHED: 04-04-2013
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This paper proposes a novel strain estimator using scale-invariant keypoints tracking (SIKT) for ultrasonic elastography. This method is based on tracking stable features between the pre- and post-compression A-lines to obtain tissue displacement estimates. The proposed features, termed scaleinvariant keypoints, are independent of signal scale change according to the scale-space theory, and therefore can preserve their patterns while undergoing a substantial range of compression. The keypoints can be produced by searching for repeatedly assigned points across all possible scales constructed from the convolution with a one-parameter family of Gaussian kernels. Because of the distinctive property of the keypoints, the SIKT method could provide a reliable tracking over changing strains, an effective resistance to anamorphic noise and sonographic noise, and a significant reduction in processing time. Simulation and experimental results show that the SIKT method is able to provide better sensitivity, a larger dynamic range of the strain filter, higher resolution, and a better contrast- to-noise ratio (CNRe) than the conventional methods. Moreover, the computation time of the SIKT method is approximately 5 times that of the cross-correlation techniques.
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Enhanced protective efficacy of H5 subtype influenza vaccine with modification of the multibasic cleavage site of hemagglutinin in retroviral pseudotypes.
Virol Sin
PUBLISHED: 03-26-2013
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Traditionally, the multibasic cleavage site (MBCS) of surface protein H5-hemagglutinin (HA) is converted to a monobasic one so as to weaken the virulence of recombinant H5N1 influenza viruses and to produce inactivated and live attenuated vaccines. Whether such modification benefits new candidate vaccines has not been adequately investigated. We previously used retroviral vectors to generate wtH5N1 pseudotypes containing the wild-type HA (wtH5) from A/swine/Anhui/ca/2004 (H5N1) virus. Here, we generated mtH5N1 pseudotypes, which contained a mutant-type HA (mtH5) with a modified monobasic cleavage site. Groups of mice were subcutaneously injected with the two types of influenza pseudotypes. Compared to the group immunized with wtH5N1 pseudotypes, the inoculation of mtH5N1 pseudotypes induced significantly higher levels of HA specific IgG and IFN-? in immunized mice, and enhanced protection against the challenge of mouse-adapted avian influenza virus A/Chicken/Henan/12/2004 (H5N1). This study suggests modification of the H5-hemagglutinin MBCS in retroviral pseudotypes enhances protection efficacy in mice and this information may be helpful for development of vaccines from mammalian cells to fight against H5N1 influenza viruses.
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A novel mechanism for vascular insulin resistance in normotensive young SHRs: hypoadiponectinemia and resultant APPL1 downregulation.
Hypertension
PUBLISHED: 03-11-2013
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Vascular insulin resistance contributes to elevated peripheral vascular resistance and subsequent hypertension. Clinical observation showed that lower plasma adiponectin concentration is significantly associated with hypertension. This study was aimed to determine whether hypoadiponectinemia induces vascular insulin resistance before systemic hypertension and the underlying mechanisms. Four-week-old young spontaneously hypertensive rats (ySHRs, normotensive) and adiponectin knockout (KO; APN(-/-)) mice were used to evaluate the role of hypoadiponectinemia in insulin-induced vasodilation of resistance vessels. ySHRs showed significant vascular insulin resistance as evidenced by the blunted vasorelaxation response to insulin in mesenteric arterioles compared with that of age-matched Wistar-Kyoto controls. Serum adiponectin and mesenteric arteriolar APPL1 (an adaptor protein that mediates adiponectin signaling) expression of ySHRs were significantly reduced. In addition, Akt and endothelial NO synthase phosphorylation and NO production in arterioles were markedly reduced, whereas extracellular signal-regulated protein kinases 1/2 (ERK1/2) phosphorylation and endothelin-1 secretion were augmented in ySHRs. APN(-/-) mice showed significantly decreased APPL1 expression and vasodilation evoked by insulin. More importantly, treatment of ySHRs in vivo with the globular domain of adiponectin for 1 week increased APPL1 expression and insulin-induced vasodilation, and restored the balance between insulin-stimulated endothelial vasodilator NO and vasoconstrictor endothelin-1. In cultured human umbilical vein endothelial cells, globular domain of adiponectin upregulated APPL1 expression. Suppression of APPL1 expression with small interfering RNA markedly blunted the globular domain of adiponectin-induced insulin sensitization as evidenced by reduced Akt/endothelial NO synthase and potentiated ERK1/2 phosphorylations. In conclusion, hypoadiponectinemia induces APPL1 downregulation in the resistance vessels, contributing to the development of vascular insulin resistance by differentially modulating the Akt/endothelial NO synthase/NO and ERK1/2/endothelin-1 pathways in vascular endothelium in normotensive ySHRs.
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A top-down strategy towards monodisperse colloidal lead sulphide quantum dots.
Nat Commun
PUBLISHED: 02-21-2013
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Monodisperse colloidal quantum dots with size dispersions <10% are of great importance in realizing functionality manipulation, as well as building advanced devices, and have been normally synthesized via bottom-up colloidal chemistry. Here we report a facile and environmentally friendly top-down strategy towards highly crystalline monodisperse colloidal PbS quantum dots with controllable sizes and narrow dispersions 5.5%
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Effect of corn stover compositional variability on minimum ethanol selling price (MESP).
Bioresour. Technol.
PUBLISHED: 02-11-2013
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A techno-economic sensitivity analysis was performed using a National Renewable Energy Laboratory (NREL) 2011 biochemical conversion design model varying feedstock compositions. A total of 496 feedstock near infrared (NIR) compositions from 47 locations in eight US Corn Belt states were used as the inputs to calculate minimum ethanol selling price (MESP), ethanol yield (gallons per dry ton biomass feedstock), ethanol annual production, as well as total installed project cost for each composition. From this study, the calculated MESP is $2.20 ± 0.21 (average ± 3 SD) per gallon ethanol.
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Reduced efficiency of functional brain network underlying intellectual decline in patients with low-grade glioma.
Neurosci. Lett.
PUBLISHED: 02-08-2013
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Low-grade glioma (LGG) patients are typically accompanied by varying degrees of intellectual impairments. However, the neural mechanisms underlying intellectual decline have not yet been well understood. The aim of this study is to investigate the relationship between possibly altered functional brain network properties and intellectual decline in LGG patients. Chinese revised Wechsler adult intelligence scale (WAIS-RC) was used to assess the intelligence of 21 LGG patients and 20 healthy controls, matched in age, gender and education. Resting-state functional magnetic resonance imaging (fMRI) was performed for all the subjects to analyze functional network characteristics with graph theory. The LGG patients showed significantly poor performance on intelligence test than controls (P<0.05). Compared with controls, the patients displayed disturbed small-world manner (increased characteristic path length L and normalized characteristic path length ?) and decreased global efficiency Eglob. Specially, we found that Eglob was positively correlated with intelligence quotient (IQ) test scores in LGG group. Furthermore, network hubs, which could significantly affect the network efficiency, were in the right insula and right posterior cingulate cortex in controls, while in the right thalamus and right posterior cingulate cortex in the patients. From the perspective of brain network, our results provided evidence of reduced global efficiency for poorer intellectual performance in LGG patients, which contributed to understanding the basis of intellectual impairments.
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Printable thermo-optic polymer switches utilizing imprinting and ink-jet printing.
Opt Express
PUBLISHED: 02-08-2013
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We demonstrate a printable Thermo-Optic (TO) switch utilizing imprinting and ink-jet printing techniques. The material system, optical and thermal designs are discussed. Imprinting technique is used to transfer a 2 × 2 switch pattern from a flexible mold into a UV15LV polymer bottom cladding. Ink-jet printing is further used to deposit a SU-8 polymer core layer on top. Operation of the switch is experimentally demonstrated up to a frequency of 1 kHz, with switching time less than 0.5 ms. The printing technique demonstrates great potential for high throughput, roll-to-roll fabrication of low cost photonic devices.
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Endothelium-dependent vasodilatation effects of the essential oil from Fructus alpiniae zerumbet (EOFAZ) on rat thoracic aortic rings in vitro.
Phytomedicine
PUBLISHED: 01-28-2013
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Fructus Alpiniae Zerumbet (FAZ) is an herb widely used to treat vascular disorders in Guizhou province, China, the essential oil has been identified as one of it vasodilation effect active components, and especial, the composition was significantly difference from the leaves. Vasodilation effects and mechanism of essential oil from FAZ (EOFAZ) were investigated. The EOFAZ showed significant vasodilation effect on endothelium-with rat thoracic aortic rings preincubated with norepinephrine (NE, 1.0?M) or KCl (60mM) in a concentration-dependent manner (1.14-72.96?g/ml). The non-selective nitric oxide synthase inhibitor l-NAME, as well as the soluble guanylate cyclase inhibitor MB, attenuated the relaxation of EOFAZ in endothelium-intact rat thoracic aortic rings. However, there were not significantly affected the vasodilation effects pretreated with cyclooxygenase inhibition by indomethacin (Indo) or ?-noradrenergic inhibition by propranolol (Prop). The present results first demonstrated that vasodilation effect of EOFAZ depending upon the endothelium and concentration, and the mechanism involvement of NOS-cGMP system. In contrast, prostacyclin and ?-adrenoceptor may not be associated with EOFAZ-induced vasorelaxation.
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Impaired mitochondrial biogenesis due to dysfunctional adiponectin-AMPK-PGC-1? signaling contributing to increased vulnerability in diabetic heart.
Basic Res. Cardiol.
PUBLISHED: 01-09-2013
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Impaired mitochondrial biogenesis causes skeletal muscle damage in diabetes. However, whether and how mitochondrial biogenesis is impaired in the diabetic heart remains largely unknown. Whether adiponectin (APN), a potent cardioprotective molecule, regulates cardiac mitochondrial function has also not been previously investigated. In this study, electron microscopy revealed significant mitochondrial disorders in ob/ob cardiomyocytes, including mitochondrial swelling and cristae disorientation and breakage. Moreover, mitochondrial biogenesis of ob/ob cardiomyocytes is significantly impaired, as evidenced by reduced Ppargc-1a/Nrf-1/Tfam mRNA levels, mitochondrial DNA content, ATP content, citrate synthase activity, complexes I/III/V activity, AMPK phosphorylation, and increased PGC-1? acetylation. Since APN is an upstream activator of AMPK and APN plasma levels are significantly reduced in ob/ob mice, we further tested the hypothesis that reduced APN in ob/ob mice is causatively related to mitochondrial biogenesis impairment. One week of APN treatment of ob/ob mice activated AMPK, reduced PGC-1? acetylation, increased mitochondrial biogenesis, and attenuated mitochondrial disorders. In contrast, knocking out APN inhibited AMPK-PGC-1? signaling and impaired both mitochondrial biogenesis and function. The ob/ob mice exhibited lower survival rates and exacerbated myocardial injury after MI, when compared to controls. APN supplementation improved mitochondrial biogenesis and attenuated MI injury, an effect that was almost completely abrogated by the AMPK inhibitor compound C. In high glucose/high fat treated neonatal rat ventricular myocytes, siRNA-mediated knockdown of PGC-1? blocked gAd-enhanced mitochondrial biogenesis and function and attenuated protection against hypoxia/reoxygenation injury. In conclusion, hypoadiponectinemia impaired AMPK-PGC-1? signaling, resulting in dysfunctional mitochondrial biogenesis that constitutes a novel mechanism for rendering diabetic hearts more vulnerable to enhanced MI injury.
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Differential regulation of TNF receptor 1 and receptor 2 in adiponectin expression following myocardial ischemia.
Int. J. Cardiol.
PUBLISHED: 01-07-2013
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In vitro experiments demonstrate that adiponectin, a cardioprotective cytokine, is inhibited by tumor necrosis factor-alpha (TNF?). However, the role of TNF? in post-myocardial infarction (post-MI) adiponectin reduction remains unclear. More importantly, the TNF receptor type (TNFR1 or TNFR2) responsible for TNF?-mediated suppression of adiponectin production is unknown. The current study determined the role of TNF? in post-myocardial infarction (post-MI) adiponectin reduction, and identified the receptor type responsible for TNF?-mediated suppression of adiponectin production.
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Autologous nerve implantation into denervated monkey skin promotes regeneration of Meissners corpuscle.
Med. Sci. Monit.
PUBLISHED: 12-02-2011
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The aim of this study was to observe the effects of autologous nerve implantation into the denervated finger flap on the regression and regeneration of sensory nerve endings and Meissners corpuscles.
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[Effects of rapamycin on cholesterol homeostasis and secretory function of 3T3-L1 cells].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 11-25-2011
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To investigate the effects of rapamycin on cholesterol homeostasis and secretory function of 3T3-L1 cells.
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[Enrichment and screening of the microsatellite markers in Microtus fortis and its preliminary application in genetic diversity research].
Yi Chuan
PUBLISHED: 09-29-2011
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This study was to isolate microsatellite markers from Microtus fortis genome by magnetic beads enrichments. Through hybridization of biotin-labeled microsatellite oligonucleotide probes, which were captured by streptavidin-coated magnetic with the adaptor-ligated enzyme-digested genome fragments, single-stranded DNA fragments containing microsatellites were obtained. After PCR amplification, these fragments were then cloned into T vectors and were transformed into competent cells subsequently. Ninety-two microsatellite sequences were randomly isolated from 70 positive clones. Twenty-one out of 27 pairs of designed microsatellite primers were screened out from the microsatellite sequences, and 10 out of the 21 microsatellite loci were used to investigate the genetic diversity of three populations of M. fortis, Hunan (wild), Hunan (domesticated), and Ningxia (domesticated). All the 10 microsatellite loci used to analyze the genetic diversity exhibited a good level of polymorphism. The values of observed number of alleles (Na), effective number of alleles (Ne), observed heterozygosity (Ho), expected heterozygosity (He) and polymorphic information content (PIC) were all the highest in the Hunan (wild) population, lower in the Hunan (domesticated) population, and the lowest in the Ningxia (domesticated) population.
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[Clinical analysis of anti glomerular basement membrane disease with normal renal function].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 09-13-2011
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To investigate the clinical and pathologic characteristics of anti-glomerular basement membrane(GBM) disease with normal renal function.
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PTEN inhibits proliferation and functions of hypertrophic scar fibroblasts.
Mol. Cell. Biochem.
PUBLISHED: 07-27-2011
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Hypertrophic scar (HS) remains a major problem in plastic surgery. In order to explore the regulative effect of phosphatase and tensin homolog (PTEN) on HS, PTEN and AKT expression was detected by reverse transcription PCR, immunohistochemistry and western blot. Adenovirus-mediated PTEN overexpression in cultured hypertrophic scar fibroblasts (HSFBs) and normal skin fibroblasts was also introduced to evaluate its biological function. Our results showed that PTEN expression was significantly decreased in HS whereas p-Akt level was significantly higher in HS compared with normal skin (P < 0.01). Furthermore, we found that adenovirus-mediated PTEN overexpression led to decreased AKT activation, and significantly reduced cell proliferation and collagen synthesis of HSFBs, while increased the apoptosis. Taken together, these data suggest that PTEN inhibits proliferation and function of HSFBs through AKT pathway. Our results reveal a novel biological role for PTEN/AKT pathway in HS and suggest PTEN as a potential therapeutic target for HS treatment.
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Single-walled carbon nanotube/pyrenecyclodextrin nanohybrids for ultrahighly sensitive and selective detection of p-nitrophenol.
Langmuir
PUBLISHED: 07-18-2011
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Electrochemical detection of p-nitrophenol (P-NP) using a highly sensitive and selective platform based on single-walled carbon nanotube/pyrenecyclodextrin (SWCNT/PyCD) nanohybrids is described for the first time. The electrochemical performance of the SWCNT/PyCD nanohybrid electrode was fully compared with bare glassy carbon, single-SWCNT, single-PyCD, and SWCNT/CD (without pyrene rings) electrodes. Besides the techniques of cyclic voltammetry and chronoamperometric transients, differential pulse voltammetry (DPV) has been used for the detection of P-NP without any interference from o-nitrophenol (O-NP) at the potentials of -0.80 and -0.67 V, respectively. The SWCNT/PyCD nanohybrid electrode is highly sensitive, and it shows an ultrahigh sensitivity of 18.7 ?A/?M toward P-NP in contrast to the values reported previously. The detection limit (S/N = 3) of the SWCNT/PyCD nanohybrid electrode toward P-NP is 0.00086 ?M (0.12 ppb), which is well below the allowed limit in drinking water, 0.43 ?M, given by the U.S. Environmental Protection Agency (EPA). The analytical performance of the SWCNT/PyCD nanohybrid electrode toward P-NP is superior to the existing electrodes.
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[A model of individually forecasting the penile length gained after penis lengthening].
Zhonghua Zheng Xing Wai Ke Za Zhi
PUBLISHED: 06-27-2011
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To establish a model of individually forecasting the penile length gained after penis lengthening.
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Redox-regulating role of insulin: the essence of insulin effect.
Mol. Cell. Endocrinol.
PUBLISHED: 06-21-2011
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It is well-known that insulin acts as an important hormone, controlling energy metabolism, cellular proliferation and biosynthesis of functional molecules to maintain a biological homeostasis. Over the past few years, intensive insulin therapy has been believed to be benefit for the outcome of diabetic patients, in which the suppression of oxidative stress plays a role. Moreover, insulin is accepted as a key component of glucose-insulin-potassium, a treatment which has been believed to exert significant cardiovascular protective effect via the reduction of oxidative stress. Furthermore, accumulating evidence has suggested that insulin exerts important redox-regulating actions in various insulin-sensitive target organs, implying the systematic antioxidative role of insulin as a hormone. It is time for us to revisit insulin effects, through summarizing and evaluating the novel functions of insulin and their mechanisms. This review focuses on the antioxidative effect of insulin and highlights insulin-induced regulation of various antioxidant enzymes via insulin signaling pathways and the cross talk between key transcription factors, including nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor ?B (NF-?B) which are responsible for the transcription of antioxidant enzymes, leading to reduced generation of reactive oxygen species (ROS) and the enhancement of the elimination of ROS.
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Pure optical photoacoustic microscopy.
Opt Express
PUBLISHED: 06-07-2011
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The concept of pure optical photoacoustic microscopy(POPAM) was proposed based on optical rastering of a focused excitation beam and optically sensing the photoacoustic signal using a microring resonator fabricated by a nanoimprinting technique. After the refinements of the microrings working wavelength and in the resonator structure and mold fabrication, an ultrahigh Q factor of 3.0×10(5) was achieved which provided high sensitivity with a noise equivalent detectable pressure(NEDP) value of 29 Pa. This NEDP is much lower than the hundreds of Pascals achieved with existing optical resonant structures such as etalons, fiber gratings and dielectric multilayer interference filters available for acoustic measurement. The featured high sensitivity allowed the microring resonator to detect the weak photoacoustic signals from micro- or submicroscale objects. The inherent superbroad bandwidth of the optical microring resonator combined with an optically focused scanning beam provided POPAM with high resolution in the axial as well as both lateral directions while the axial resolution of conventional photoacoustic microscopy (PAM) suffers from the limited bandwidth of PZT detectors. Furthermore, the broadband microring resonator showed similar sensitivity to that of our most sensitive PZT detector. The current POPAM system provides a lateral resolution of 5 ?m and an axial resolution of 8 ?m, comparable to that achieved by optical microscopy while presenting the unique contrast of optical absorption and functional information complementing other optical modalities. The 3D structure of microvasculature, including capillary networks, and even individual red blood cells have been discerned successfully in the proof-of-concept experiments on mouse bladders ex vivo and mouse ears in vivo. The potential of approximately GHz bandwidth of the microring resonator also might allow much higher resolution than shown here in microscopy of optical absorption and acoustic propagation properties at depths in unfrozen tissue specimens or thicker tissue sections, which is not now imageable with current optical or acoustic microscopes of comparable resolution.
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Low-noise small-size microring ultrasonic detectors for high-resolution photoacoustic imaging.
J Biomed Opt
PUBLISHED: 06-07-2011
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Small size polymer microring resonators have been exploited for photoacoustic (PA) imaging. To demonstrate the advantages of the wide acceptance angle of ultrasound detection of small size microrings, photoacoustic tomography (PAT), and delay-and-sum beamforming PA imaging was conducted. In PAT, we compared the imaging quality using different sizes of detectors with similar noise-equivalent pressures and the same wideband response: 500 ?m hydrophone and 100, 60, and 40 ?m microrings. The results show significantly improved imaging contrast and high resolution over the whole imaging region using smaller size detectors. The uniform high resolution in PAT imaging using 40 ?m microrings indicates the potential to resolve microvasculature over a large imaging region. The improved lateral resolution of two-dimensional and three-dimensional delay-and-sum beamforming PA imaging using a synthetic array demonstrate another advantageous application of small microrings. The small microrings can also be applied to other ultrasound-related imaging applications.
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Cyclosporine treatment in idiopathic membranous nephropathy nephrotic syndrome in adults: a retrospective study spanning 15 years.
Chin. Med. J.
PUBLISHED: 05-31-2011
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Cyclosporine is effective in treating nephrotic syndrome (NS) with idiopathic membranous nephropathy (IMN) in adults. But high relapse rate remains a major concern. The way to manipulate cyclosporine is inconclusive. The aim of this study was to introduce the way how to titrate the cyclosporine to maintain complete remission without relapse.
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Dynamic alteration of adiponectin/adiponectin receptor expression and its impact on myocardial ischemia/reperfusion in type 1 diabetic mice.
Am. J. Physiol. Endocrinol. Metab.
PUBLISHED: 05-17-2011
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The present study determined the dynamic change of adiponectin (APN, a cardioprotective adipokine), its receptor expression, and their impact upon myocardial ischemia/reperfusion (MI/R) injury during type 1 diabetes mellitus (T1DM) progression, and involved underlying mechanisms. Diabetic state was induced in mice via multiple intraperitoneal injections of low-dose streptozotocin. The dynamic change of plasma APN concentration and cardiac APN receptor-1 and -2 (AdipoR1/2) expression were assessed immediately after diabetes onset (0 wk) and 1, 3, 5, and 7 wk thereafter. Indicators of MI/R injury (infarct size, apoptosis, and LDH release) were determined at 0, 1, and 7 wk of DM duration. The effect of APN on MI/R injury was determined in mice subjected to different diabetic durations. Plasma APN levels (total and HMW form) increased, whereas cardiac AdipoR1 expression decreased early after T1DM onset. With T1DM progression, APN levels were reduced and cardiac AdipoR1 expression increased. MI/R injury was exacerbated with T1DM progression in a time-dependent manner. Administration of globular APN (gAD) failed to attenuate MI/R injury in 1-wk T1DM mice, while an AMP-activated protein kinase (AMPK) activator (AICAR) reduced MI/R injury. However, administration of gAD (and AICAR) reduced infarct size and cardiomyocyte apoptosis in 7-wk T1DM mice. In conclusion, our results demonstrate a dynamic dysfunction of APN/AdipoR1 during T1DM progression. Reduced cardiac AdipoR1 expression and APN concentration may be responsible for increased I/R injury susceptibility at early and late T1DM stages, respectively. Interventions bolstering AdipoR1 expression during early T1DM stages and APN supplementation during advanced T1DM stages may potentially reduce the myocardial ischemic injury in diabetic patients.
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Facile synthesis of zinc hydroxide carbonate flowers on zinc oxide nanorods with attractive luminescent and optochemical performance.
Nanotechnology
PUBLISHED: 05-04-2011
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A simple synthesis route was designed to fabricate a functional composite, zinc hydroxide carbonate (ZHC) flowers on zinc oxide (ZnO) nanorods. The hydrolysis of hexamethylenetetramine (HMT) can generate various species which are slowly released and gradually change reaction modes in a Zn(NO(3))(2)/HMT solution. As a result, ZnO nanorods and ZHC flowers can be sequentially synthesized and connect very well under constant experimental conditions. The obtained composite has the advantages of both components and exhibits attractive properties. For instance, ZHC flowers on ZnO nanorods exhibit strong blue emission under the excitation of ultraviolet light, and dye-sensitized solar cells with the annealed composite as photoanode achieve much higher conversion efficiency than pure nanorod arrays.
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Advanced glycation end products accelerate ischemia/reperfusion injury through receptor of advanced end product/nitrative thioredoxin inactivation in cardiac microvascular endothelial cells.
Antioxid. Redox Signal.
PUBLISHED: 04-26-2011
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The advanced glycation end products (AGEs) are associated with increased cardiac endothelial injury. However, no causative link has been established between increased AGEs and enhanced endothelial injury after ischemia/reperfusion. More importantly, the molecular mechanisms by which AGEs may increase endothelial injury remain unknown. Adult rat cardiac microvascular endothelial cells (CMECs) were isolated and incubated with AGE-modified bovine serum albumin (BSA) or BSA. After AGE-BSA or BSA preculture, CMECs were subjected to simulated ischemia (SI)/reperfusion (R). AGE-BSA increased SI/R injury as evidenced by enhanced lactate dehydrogenase release and caspase-3 activity. Moreover, AGE-BSA significantly increased SI/R-induced oxidative/nitrative stress in CMECs (as measured by increased inducible nitric oxide synthase expression, total nitric oxide production, superoxide generation, and peroxynitrite formation) and increased SI/R-induced nitrative inactivation of thioredoxin-1 (Trx-1), an essential cytoprotective molecule. Supplementation of EUK134 (peroxynitrite decomposition catalyst), human Trx-1, or soluble receptor of advanced end product (sRAGE) (a RAGE decoy) in AGE-BSA precultured cells attenuated SI/R-induced oxidative/nitrative stress, reduced SI/R-induced Trx-1 nitration, preserved Trx-1 activity, and reduced SI/R injury. Our results demonstrated that AGEs may increase SI/R-induced endothelial injury by increasing oxidative/nitrative injury and subsequent nitrative inactivation of Trx-1. Interventions blocking RAGE signaling or restoring Trx activity may be novel therapies to mitigate endothelial ischemia/reperfusion injury in the diabetic population.
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Systemic adiponectin malfunction as a risk factor for cardiovascular disease.
Antioxid. Redox Signal.
PUBLISHED: 04-20-2011
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Adiponectin (Ad) is an abundant protein hormone regulatory of numerous metabolic processes. The 30 kDa protein originates from adipose tissue, with full-length and globular domain circulatory forms. A collagenous domain within Ad leads to spontaneous self-assemblage into various oligomeric isoforms, including trimers, hexamers, and high-molecular-weight multimers. Two membrane-spanning receptors for Ad have been identified, with differing concentration distribution in various body tissues. The major intracellular pathway activated by Ad includes phosphorylation of AMP-activated protein kinase, which is responsible for many of Ads metabolic regulatory, anti-inflammatory, vascular protective, and anti-ischemic properties. Additionally, several AMP-activated protein kinase-independent mechanisms responsible for Ads anti-inflammatory and anti-ischemic (resulting in cardioprotective) effects have also been discovered. Since its 1995 discovery, Ad has garnered considerable attention for its role in diabetic and cardiovascular pathology. Clinical observations have demonstrated the association of hypoadiponectinemia in patients with obesity, cardiovascular disease, and insulin resistance. In this review, we elaborate currently known information about Ad malfunction and deficiency pertaining to cardiovascular disease risk (including atherosclerosis, endothelial dysfunction, and cardiac injury), as well as review evidence supporting Ad resistance as a novel risk factor for cardiovascular injury, providing insight about the future of Ad research and the proteins potential therapeutic benefits.
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Downregulation of adiponectin induced by tumor necrosis factor ? is involved in the aggravation of posttraumatic myocardial ischemia/reperfusion injury.
Crit. Care Med.
PUBLISHED: 04-19-2011
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Recent clinical observations have indicated that nonlethal mechanical trauma significantly increases myocardial infarction risk even in the presence of completely normal coronary arteries. We investigated the molecular mechanisms responsible for exacerbation of ischemic myocardial injury after nonlethal mechanical trauma with a special focus on the role of tumor necrosis factor ? and its potential downstream effector adiponectin, a novel adipokine with anti-inflammatory and cardioprotective properties.
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Reduced cardioprotective action of adiponectin in high-fat diet-induced type II diabetic mice and its underlying mechanisms.
Antioxid. Redox Signal.
PUBLISHED: 04-11-2011
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Diabetes exacerbates ischemic heart disease morbidity and mortality via incompletely understood mechanisms. Although adiponectin (APN) reduces myocardial ischemia/reperfusion (MI/R) injury in nondiabetic animals, whether APNs cardioprotective actions are altered in diabetes, a pathologic condition with endogenously reduced APN, has never been investigated. High-fat diet (HD)-induced diabetic mice and normal diet (ND) controls were subjected to MI via coronary artery ligation, and given vehicle or APN globular domain (gAPN, 2 ?g/g) 10 min before reperfusion. Compared to ND mice (where gAPN exerted pronounced cardioprotection), HD mice manifested greater MI/R injury, and a tripled gAPN dose was requisite to achieve cardioprotective extent seen in ND mice (i.e., infarct size, apoptosis, and cardiac function). APN reduces MI/R injury via AMP-activated protein kinase (AMPK)-dependent metabolic regulation and AMPK-independent antioxidative/antinitrative pathways. Compared to ND, HD mice manifested significantly blunted gAPN-induced AMPK activation, basally and after MI/R (p<0.05). Although both low- and high-dose gAPN equally attenuated MI/R-induced oxidative stress (i.e., NADPH oxidase expression and superoxide production) and nitrative stress (i.e., inducible nitric oxide synthase expression, nitric oxide production, and peroxynitrite formation) in ND mice, only high-dose gAPN efficaciously did so in HD mice. We demonstrate for the first time that HD-induced diabetes diminished both AMPK-dependent and AMPK-independent APN cardioprotection, suggesting an unreported diabetic heart APN resistance.
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Electrochemical impedance determination of polychlorinated biphenyl using a pyrenecyclodextrin-decorated single-walled carbon nanotube hybrid.
Chem. Commun. (Camb.)
PUBLISHED: 03-30-2011
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This work reports the first detailed study on an electrochemical impedance sensor for determination of polychlorinated biphenyl (PCB), such as 3,3,4,4-tetrachlorobiphenyl (PCB-77), based on a single-walled carbon nanotube/pyrenecyclodextrin (SWCNT/PyCD) hybrid.
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Process and technoeconomic analysis of leading pretreatment technologies for lignocellulosic ethanol production using switchgrass.
Bioresour. Technol.
PUBLISHED: 03-29-2011
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Six biomass pretreatment processes to convert switchgrass to fermentable sugars and ultimately to cellulosic ethanol are compared on a consistent basis in this technoeconomic analysis. The six pretreatment processes are ammonia fiber expansion (AFEX), dilute acid (DA), lime, liquid hot water (LHW), soaking in aqueous ammonia (SAA), and sulfur dioxide-impregnated steam explosion (SO(2)). Each pretreatment process is modeled in the framework of an existing biochemical design model so that systematic variations of process-related changes are consistently captured. The pretreatment area process design and simulation are based on the research data generated within the Biomass Refining Consortium for Applied Fundamentals and Innovation (CAFI) 3 project. Overall ethanol production, total capital investment, and minimum ethanol selling price (MESP) are reported along with selected sensitivity analysis. The results show limited differentiation between the projected economic performances of the pretreatment options, except for processes that exhibit significantly lower monomer sugar and resulting ethanol yields.
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[Immune tolerance induced by bone marrow cell transplantation combined with use of cyclophosphamide in diabetic rats with pancreatic transplantation].
Sichuan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 03-02-2011
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To study the immune tolerance induced by bone marrow cell transplantation combined with short-term use of cyclophosphamide after pancreatic transplantation in diabetic rats.
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High-sensitivity and wide-directivity ultrasound detection using high Q polymer microring resonators.
Appl Phys Lett
PUBLISHED: 02-25-2011
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Small size ultrahigh Q polymer microrings working at near visible wavelength have been experimentally demonstrated as ultralow noise ultrasound detectors with wide directivity at high frequencies (>20 MHz). By combining a resist reflow and a low bias continuous etching and passivation process in mold fabrication, imprinted polymer microrings with drastically improved sidewall smoothness were obtained. An ultralow noise-equivalent pressure of 21.4 Pa over 1-75 MHz range has been achieved using a fabricated detector of 60 ?m diameter. The devices wide acceptance angle with high sensitivity considerably benefits ultrasound-related imaging.
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An atypical HLH protein OsLF in rice regulates flowering time and interacts with OsPIL13 and OsPIL15.
N Biotechnol
PUBLISHED: 02-22-2011
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In plants, flowering as a crucial developmental event is highly regulated by both genetic programs and environmental signals. Genetic analysis of flowering time mutants is instrumental in dissecting the regulatory pathways of flowering induction. In this study, we isolated the OsLF gene by its association with the T-DNA insertion in the rice late flowering mutant named A654. The OsLF gene encodes an atypical HLH protein composed of 419 amino acids (aa). Overexpression of the OsLF gene in wild type rice recapitulated the late flowering phenotype of A654, indicating that the OsLF gene negatively regulates flowering. Flowering genes downstream of OsPRR1 such as OsGI and Hd1 were down regulated in the A654 mutant. Yeast two hybrid and colocalization assays revealed that OsLF interacts strongly with OsPIL13 and OsPIL15 that are potentially involved in light signaling. In addition, OsPIL13 and OsPIL15 colocalize with OsPRR1, an ortholog of the Arabidopsis APRR1 gene that controls photoperiodic flowering response through clock function. Together, these results suggest that overexpression of OsLF might repress expression of OsGI and Hd1 by competing with OsPRR1 in interacting with OsPIL13 and OsPIL15 and thus induce late flowering.
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Therapeutic ultrasonic microbubbles carrying paclitaxel and LyP-1 peptide: preparation, characterization and application to ultrasound-assisted chemotherapy in breast cancer cells.
Ultrasound Med Biol
PUBLISHED: 02-16-2011
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The aim of this work was to develop a novel targeted drug-loaded microbubble (MB) and to investigate its chemotherapy effect in vitro. Paclitaxel (PTX)-loaded lipid MBs were prepared by a mechanical vibration technique. The LyP-1, a breast tumor homing peptide, was coated onto the surface of PTX-loaded MBs through biotin-avidin linkage. The resulting targeted drug-loaded MBs were characterized and applied to ultrasound-assisted chemotherapy in breast cancer cells. Our results showed the ultrasonic MBs were able to achieve 43%-63% of drug encapsulation efficiency, depending on drug loading amount. The binding affinity assay indicated the attachment of targeted MBs to human MDA-MB-231 breast cancer cells was highly efficient and stable even with ultrasonic irradiation on. The cellular uptake efficiency of payload in targeted MBs was 3.71-, 4.95-, 7.43- and 7.66-fold higher than that of non-targeted MBs at the applied ultrasound time of 30, 60, 90 and 120 s, respectively. In addition, the cell proliferation inhibition assay showed the cell viability of targeted PTX-loaded MBs was significantly lower than that of non-targeted PTX-loaded MBs and non-targeted unloaded MBs when ultrasound was utilized. In conclusion, the study indicated the LyP-1-coated PTX-loaded MBs significantly increased the antitumor efficacy and can be used as a potential chemotherapy approach for ultrasound-assisted breast cancer treatment.
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Th17/Treg imbalance in adult patients with minimal change nephrotic syndrome.
Clin. Immunol.
PUBLISHED: 01-26-2011
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To determine whether Th17/Treg balance was abnormal in adult patients with minimal change nephrotic syndrome (MCNS), we studied 25 patients with new-onset MCNS and 20 normal persons. The results showed that MCNS patients exhibited a significant increase in Th17 number, Th17-related cytokines (IL-17 and IL-23), and transcription factor (ROR?t) levels, as well as an obvious decrease in Treg number, Treg-related cytokines (TGF-?1 and IL-10), and transcription factor (Foxp3) levels. The Th17/Treg ratios increased along with increased proteinuria and decreased albumin levels in patients with MCNS. IL-17 protein expression was also detected in the renal biopsy tissue of MCNS patients, particularly in patients with acute renal failure. Further, Th17/Treg balance returned to normal after effective corticosteroids therapy in 16 MCNS patients. These results indicated that Th17/Treg imbalance existed in MCNS patients, suggesting a potential role of Th17/Treg imbalance in the pathogenesis of MCNS.
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Fabrication and characterization of high Q polymer micro-ring resonator and its application as a sensitive ultrasonic detector.
Opt Express
PUBLISHED: 01-26-2011
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Smooth sidewall silicon micro-ring molds have been fabricated using resist reflow and thermal oxidation method. High Q factor polymer micro-ring resonators have been fabricated using these molds. Quality factors as high as 10(5) have been measured at telecommunication wavelength range. By carefully examining the different loss mechanisms in polymer micro-ring, we find that the surface scattering loss can be as low as 0.23 dB/cm, much smaller than the absorption loss of the polystyrene polymer used in our devices. When used as an ultrasound detector such a high Q polymer micro-ring device can achieve an acoustic sensitivity around 36.3 mV/kPa with 240 ?W operating power. A noise equivalent pressure (NEP) is around 88 Pa over a bandwidth range of 1-75 MHz. We have improved the NEP by a factor of 3 compared to our previous best result.
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Identification and characterization of the pumilio-2 expressed in zebrafish embryos and adult tissues.
Mol. Biol. Rep.
PUBLISHED: 01-04-2011
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Pumilio proteins regulate the translation of specific proteins required for germ cell development and morphogenesis. In the present study, we have identified the pumilio-2 in zebrafish and analyze its expression in adult tissues and early embryos. Pumilio-2 codes for the full-length Pumilio-2 protein and contains a PUF-domain. When compared to the mammalian and avian Pumilio-2 proteins, zebrafish Pumilio-2 protein was found to contain an additional sequence of 24 amino acid residues within the PUF-domain. Zebrafish pumilio-2 mRNA is expressed in the ovary, testis, liver, kidney and brain but is absent in the heart and muscle as detected by RT-PCR. The results of in situ hybridization indicate that transcripts of pumilio-2 are distributed in all blastomeres from the 1-cell stage to the sphere stage and accumulate in the head and tail during the 60%-epiboly and 3-somite stages. Transcripts were also detected in the brain and neural tube of the 24 h post-fertilization (hpf) embryos. Western blot analyses indicate that the Pumilio-2 protein is strongly expressed in the ovary, testis and brain but not in other tissues. These data suggest that pumilio-2 plays an important role in the development of the zebrafish germ cells and nervous system.
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[Research advances in podocyte injury and its role in diabetic nephropathy].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 11-06-2010
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Diabetic nephropathy is one of the most common microvascular complications of diabetes mellitus. With an increasing prevalence, its proportion in end-stage renal diseases is ascending. Research on the mechanism of diabetic nephropathy was initially focused on the mesangial matrix and glomerular basement membrane. In recent years, changes in the structure and functions of glomerular filtration barriers, especially podocyte injury, has became new hotspots. Podocyte injury involves the decreases in the density and amount of podocytes, the hypertrophy and degeneration of podocytes, and foot-process effacement, along with changes in some specific protein structure and functions. It is the result of multiple factors and multiple pathways. This articles summarizes the common features of podocyte injury and its role in the development of diabetic nephropathy.
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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.