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Find video protocols related to scientific articles indexed in Pubmed.
A netlike rolling circle nucleic acid amplification technique.
Analyst
PUBLISHED: 11-20-2014
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A nucleic acid amplification technique termed as netlike rolling circle amplification is proposed by introducing a nicking enzyme into the existing hyperbranched rolling circle amplification system. Surprisingly dense and uniform network morphology is observed; and cubic amplification is achieved for the sensitive detection of a sequence from HIV.
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An ATP-responsive smart gate fabricated with a graphene oxide-aptamer-nanochannel architecture.
Chem. Commun. (Camb.)
PUBLISHED: 11-20-2014
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Here, we report a graphene oxide-aptamer-nanochannel architecture for the fabrication of a novel stimuli-responsive gate. The gate is switched OFF in the absence of ATP, and is switched ON when ATP is present. The concept we proposed may contribute to a versatile platform for the development of stimuli-responsive gates.
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Designed TALE proteins efficiently induced the expression of latent HIV-1 in latently infected cells.
AIDS Res. Hum. Retroviruses
PUBLISHED: 11-19-2014
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HIV latency is the foremost barrier to clearing HIV infection from patients. Reactivation of latent HIV-1 represents a promising strategy to deplete these viral reservoirs. Here, we report a novel approach to reactivate latent HIV-1 provirus using artificially designed transcription activator-like effector (TALE) fusion proteins containing a DNA-binding domain specifically targeting the HIV-1 promoter and the herpes simplex virus-based transcriptional activator VP64 domain. We engineered four TALE genes (TALE1-4) encoding TALE proteins, each specifically targeting different 20-bp DNA sequences within the HIV-1 promoter, and we constructed four TALE-VP64 expression vectors corresponding to TALE1-4. We found that TALE1-VP64 effectively reactivated HIV-1 gene expression in latently infected C11 and A10.6 cells. We further confirmed that TALE1-VP64 reactivated latent HIV-1 via specific binding to the HIV-LTR promoter. Moreover, we also found that TALE1-VP64 did not affect cell proliferation or cell cycle distribution. Taken together, our data demonstrated that TALE1-VP64 can specifically and effectively reactivate latent HIV-1 transcription, suggesting that this strategy may provide a novel approach for anti-HIV-1 latency therapy in the future.
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A Method to Study Stoichiometry of Protein Post-translational Modification.
Anal. Chem.
PUBLISHED: 11-18-2014
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We report a new method to study stoichiometry of protein post-translational modification (PTM) via manipulating small-molecule labels. Such labels can simultaneously bind with all the modified amino acids in a target protein, resulting in large signal. However, if the small-molecule labels are previously attached with macromolecule comparable to the target protein in size, binding of one such label will prevent subsequent binding of more labels of its kind, thus only one of the modified amino acids in the target protein can be bound with the label, resulting in small signal. Therefore, the stoichiometric number of PTM can be determined by ratio of the two signals. The proposed method can analyze nitration of several essential regulatory proteins of cellular life, all of which are found to have integer stoichiometric number indicating regulated site-specific nitration. These results validate the efficacy of our method to provide detailed information on PTMs with biological significance.
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General Form for Obtaining Unit Disc-based Generalized Orthogonal Moments.
IEEE Trans Image Process
PUBLISHED: 11-01-2014
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The rotation invariance of the classical disc-based moments, such as Zernike moments (ZMs), pseudo-Zernike moments (PZMs), and orthogonal Fourier-Mellin moments (OFMMs), makes them attractive as descriptors for the purpose of recognition tasks. However, less work has been performed for the generalization of these moment functions. In this paper, four general forms are developed to obtain a class of disc-based generalized radial polynomials that are orthogonal over the unit circle. These radial polynomials are scaled to ensure numerical stability, and some useful properties are discussed for potential applications they could be used in. Then, these scaled radial polynomials are used as kernel functions to construct a series of unit disc-based generalized orthogonal moments (DGMs). The variation of parameters in DGMs can form various types of orthogonal moments: generalized Zernike moments (GZMs), generalized pseudo-Zernike moments (GPZMs), generalized Fourier- Mellin moments (GOFMMs), and so on. The classical ZMs, PZMs and OFMMs correspond to a special case of these three generalized moments for which the free parameter = 0. Each member of this family will share some excellent properties for image representation and recognition tasks, such as orthogonality and rotation invariance. Additionally, we have also developed two algorithms, the so-called m-recursive and n-recursive methods for the computation of these proposed radial polynomials in order to improve the numerical stability. Experimental results show that the proposed methods are superior to the classical disc-based moments in terms of image representation capability and classification accuracy.
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Smoking and perceived stress in relation to short salivary telomere length among caregivers of children with disabilities.
Stress
PUBLISHED: 09-27-2014
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Abstract Telomere length (TL), the length of repeated DNA sequence that forms protective caps at the end of chromosomes, has emerged as a novel biomarker of cell aging and oxidative stress. There is increasing research exploring the associations of smoking and perceived stress with TL, and the results are inconsistent. This study aimed to examine whether smoking and perceived stress were associated with shortened salivary TL among primary caregivers of children with disabilities. Using a quantitative polymerase chain reaction method, salivary TL was assessed among 89 caregivers aged 19-69 years (87% were women) who took care of disabled children in the Patagonia Region, Chile. Interviewer-administered questionnaires were used to collect information on sociodemographic and lifestyle behaviors. The 14-item Perceived Stress Scale was used to assess perceived stress. Mean relative TL was 0.92 (standard error=0.03). Smokers had age-adjusted mean TL that was 0.07 units lower (beta=-0.07, standard error=0.03; p=0.012) than non-smokers. Smokers were 2.17 times more likely to have shorter TL (<0.73, the lowest quartile of TL) than non-smokers (odds ratio =3.17; 95% confidence interval=1.05-9.52) with adjustment for age and perceived stress. Caregivers with higher perceived stress were 2.13 times more likely to have shorter TL (odds ratio=3.13; 95% confidence interval=1.03-9.55) than caregivers with lower perceived stress after adjustment for age and smoking. This study provides the first evidence of strong associations between smoking and perceived stress and shortened salivary TL among caregivers of children with disabilities. Larger studies with detailed information on smoking status are warranted to confirm our findings.
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Salvage Lymphadenectomy Versus Salvage Radiotherapy/Chemoradiotherapy for Recurrence in Cervical Lymph Node After Curative Resection of Esophageal Squamous Cell Carcinoma.
Ann. Surg. Oncol.
PUBLISHED: 08-26-2014
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A consensus treatment strategy for patients with esophageal squamous cell carcinoma (ESCC) that recurs after definitive esophagectomy has not been established. This study compared outcomes in ESCC patients who underwent salvage lymphadenectomy and those who underwent salvage radiotherapy/chemoradiotherapy for recurrence in cervical lymph nodes.
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Percutaneous closure of ruptured sinus of Valsalva aneurysm: results from a multicentre experience.
EuroIntervention
PUBLISHED: 08-21-2014
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To evaluate the safety and efficacy of percutaneous closure (PC) using modified double-disc ventricular septal defect (VSD) occluders in patients with ruptured sinus of Valsalva aneurysm (RSVA).
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Recurrent 8q13.2-13.3 microdeletions associated with Branchio-oto-renal syndrome are mediated by human endogenous retroviral (HERV) sequence blocks.
BMC Med. Genet.
PUBLISHED: 08-19-2014
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Human endogenous retroviral (HERV) sequences are the remnants of ancient retroviral infection and comprise approximately 8% of the human genome. The high abundance and interspersed nature of homologous HERV sequences make them ideal substrates for genomic rearrangements. A role for HERV sequences in mediating human disease-associated rearrangement has been reported but is likely currently underappreciated.
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Lipocalin 2 is a regulator of macrophage polarization and NF-?B/STAT3 pathway activation.
Mol. Endocrinol.
PUBLISHED: 08-15-2014
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Lipocalin 2 (Lcn2) has been previously characterized as an adipokine/cytokine and implicated in obesity and inflammation. Herein, we investigated the role and potential mechanism of Lcn2 in the regulation of macrophage polarization in obesity-associated inflammation. We observed that Lcn2-/- mice displayed an up-regulation of expression of M1 macrophage marker Cd11c but a down-regulation of M2 marker arginase 1 in adipose tissue and liver of mice upon a high-fat diet feeding. Lcn2-deficient bone marrow-derived macrophages (BMDMs) were more sensitive to lipopolysaccharide (LPS) stimulation, leading to a more profound up-regulation of expression of pro-inflammatory markers than wild-type (WT) BMDMs. Accordingly, LPS stimulation elicited an increase in the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-?B), c-Jun, and STAT3 signaling pathways as well as an up-regualtion of expression of NF-?B and STAT3 target genes such as IL-1?, IL-6, iNOS, and MCP-1 in Lcn2-/- BMDMs compared with WT controls. Pre-treatment of recombinant Lcn2 attenuated LPS-stimulated degradation of I?B? and STAT3 phosphorylation as well as LPS-induced gene expression of IL-6 and iNOS in Lcn2-/- BMDMs. Moreover, the NF?B inhibitor markedly blocked LPS-stimulated STAT3 phosphorylation in Lcn2-/- BMDMs. These results together with the time course of Lcn2 secretion, NF?B and STAT3 phosphorylation in response to LPS stimulation, suggest that Lcn2 plays a role as an anti-inflammatory regulator in macrophage activation via modulating a feed-forward activation of NF?B-STAT3 loop.
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A prospective study of biomarker-guided chemotherapy in patients with non-small cell lung cancer.
Cancer Chemother. Pharmacol.
PUBLISHED: 08-14-2014
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To assess the therapeutic value of biomarker-guided chemotherapy in patients with advanced non-small cell lung cancer (NSCLC).
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Attitudes, beliefs, and perceptions of caregivers and rehabilitation providers about disabled children's sleep health: a qualitative study.
BMC Pediatr
PUBLISHED: 07-18-2014
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Children with disabilities are more likely to have sleep disturbances than children without disabilities. Identifying attitudes, beliefs, knowledge, and perceptions of caregivers and health professionals is essential in developing effective intervention programs to improve disabled children's sleep health. However, no such qualitative data about adults who have key roles in the life and daytime activities of children with disabilities are available. This qualitative study aimed to understand attitudes, beliefs, knowledge, and perceptions about disabled children's sleep hygiene among caregivers and rehabilitation providers of children with disabilities.
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Racial/Ethnic Differences in Sleep Disturbances: The Multi-Ethnic Study of Atherosclerosis (MESA).
Sleep
PUBLISHED: 07-16-2014
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There is limited research on racial/ethnic variation in sleep disturbances. This study aimed to quantify the distributions of objectively measured sleep-disordered breathing (SDB), short sleep duration, poor sleep quality, and self-reported sleep disturbances (e.g., insomnia) across racial/ethnic groups.
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Free-standing three-dimensional graphene/manganese oxide hybrids as binder-free electrode materials for energy storage applications.
ACS Appl Mater Interfaces
PUBLISHED: 07-10-2014
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Novel three-dimensional (3D) hybrid materials, i.e., free-standing 3D graphene-supported MnO2 nanosheets, are prepared by a simple and controllable solution-phase assembly process. Characterization results show that MnO2 nanosheets are uniformly anchored on a 3D graphene framework with strong adhesion and the integral hybrids show desirable mechanical strength. Such unique structure of 3D graphene/MnO2 hybrids thus provides the right characteristics of binder-free electrode materials and could enable the design of different kinds of high-performance energy storage devices. Especially, an advanced asymmetric supercapacitor is built by using a 3D graphene/MnO2 hybrid and a 3D graphene as two electrodes, and it is able to work reversibly in a full operation voltage region of 0-3.5 V in an ionic liquid electrolyte and thus exhibits a high energy density of 68.4 Wh/kg. As the cathode materials for Li-O2 and Li-MnO2 batteries, the 3D graphene/MnO2 hybrids exhibit outstanding performances, including good catalytic capability, high reversible capacity and desirable cycling stability. The results presented here may pave a way for new promising applications of such 3D graphene/MnO2 hybrids in advanced electrochemical energy storage devices.
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New Cu?TeO? ceramics: phase formation and dielectric properties.
ACS Appl Mater Interfaces
PUBLISHED: 07-08-2014
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Targeting low temperature cofired ceramics (LTCC) applications and base-metal electrode multilayer ceramic capacitors (BME-MLCCs), ceramics of a new composition, tricopper tellurate (Cu3TeO6), are reported here. The crystal structure of Cu3TeO6 was determined to be cubic, Ia3, with the unit cell parameter a = 9.538 Å. The sequence of phase formation is proposed with the oxidation of tetravalent tellurium (Te(4+)) into hexavalent tellurium (Te(6+)) as a key step for the formation of Cu3TeO6. Ceramics sintered at 865 °C with densities of 94% exhibit two dielectric anomalies in the temperature dependence of the dielectric response, around -150 °C and +50 °C, respectively, accompanied by obvious frequency dispersion of the relative permittivity (?(r)) and dielectric losses (tan ?), with an Arrhenius like behavior. A temperature stable dielectric region (near room temperature) formed between the two anomalies with ?(r) ? 12 and tan ? ? 0.01, and a very low positive temperature coefficient of the relative permittivity (TC?(r)), 2.07 × 10(-4) °C(-1), was obtained in the same region. The low temperature dielectric anomaly is associated with the possible mixed Cu(+)/Cu(2+) valence in Cu3TeO6 ceramics, while the high temperature anomaly is attributed to point defect ordering, including VO, CuCu2+(+)', which might be formed during sintering. Therefore, Cu3TeO6 ceramics are of interest in view of not only the possible applications in BME-MLCCs, LTCC, and related technologies, but also for their possible compatibility with low cost abundant Cu electrodes.
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Band-Selective Infrared Photodetectors with Complete-Composition-Range InAsx P1-x Alloy Nanowires.
Adv. Mater. Weinheim
PUBLISHED: 07-02-2014
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Band-selective infrared photodetectors (PDs) are constructed with InAsx P1-x alloy nanowires from the complete composition range (0 ? x ? 1) achieved by a new growth route combining the vapor-liquid-solid mechanism with an additional ion-exchange process. Increasing the composition x value from 0 to 1 in the PDs allows the peak response wavelength to be gradually tuned from ca. 900 to ca. 2900 nm.
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High-viscosity dietary fibers reduce adiposity and decrease hepatic steatosis in rats fed a high-fat diet.
J. Nutr.
PUBLISHED: 07-02-2014
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Viscous dietary fiber consumption lowers the postprandial glucose curve and may decrease obesity and associated comorbidities such as insulin resistance and fatty liver. We determined the effect of 2 viscous fibers, one fermentable and one not, on the development of adiposity, fatty liver, and metabolic flexibility in a model of diet-induced obesity. Rats were fed a normal-fat (NF) diet (26% energy from fat), a high-fat diet (60% energy from fat), each containing 5% fiber as cellulose (CL; nonviscous and nonfermentable), or 5% of 1 of 2 highly viscous fibers-hydroxypropyl methylcellulose (HPMC; nonfermentable) or guar gum (GG; fermentable). After 10 wk, fat mass percentage in the NF (18.0%; P = 0.03) and GG groups (17.0%; P < 0.01) was lower than the CL group (20.7%). The epididymal fat pad weight of the NF (3.9 g; P = 0.04), HPMC (3.9 g; P = 0.03), and GG groups (3.6 g; P < 0.01) was also lower than the CL group (5.0 g). The HPMC (0.11 g/g liver) and GG (0.092 g/g liver) groups had lower liver lipid concentrations compared with the CL group (0.14 g/g liver). Fat mass percentage, epididymal fat pad weight, and liver lipid concentration were not different among the NF, HPMC, and GG groups. The respiratory quotient was higher during the transition from the diet-deprived to fed state in the GG group (P = 0.002) and tended to be higher in the HPMC group (P = 0.06) compared with the CL group, suggesting a quicker shift from fatty acid (FA) to carbohydrate oxidation. The HPMC group [15.1 nmol/(mg ? h)] had higher ex vivo palmitate oxidation in muscle compared with the GG [11.7 nmol/(mg ? h); P = 0.04] and CL groups [10.8 nmol/(mg ? h); P < 0.01], implying a higher capacity to oxidize FAs. Viscous fibers can reduce the adiposity and hepatic steatosis that accompany a high-fat diet, and increase metabolic flexibility, regardless of fermentability.
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Eicosapentaenoic acid promotes thermogenic and fatty acid storage capacity in mouse subcutaneous adipocytes.
Biochem. Biophys. Res. Commun.
PUBLISHED: 06-27-2014
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In this study, we determined if eicosapentaenoic acid (EPA) promotes beneficial metabolic activities of subcutaneous adipocytes. Stromal-vascular (SV) cells were isolated from inguinal adipose tissue of C57BL/6 mice and induced to differentiate into adipocytes. EPA effect on thermogenic and mitochondrial gene expression and oxidative metabolism were assessed in inguinal adipocytes. When added to SV cell cultures during 8 day differentiation, EPA significantly increased the expression of thermogenic genes UCP1-3, CIDEA and VEGF?. Moreover, EPA increased mitochondrial DNA content and the expression of genes involved in mitochondrial biogenesis including PGC1?, Nrf1 and COXiv. However, this effect was not perceived when EPA was added to mature inguinal adipocytes for 24h, suggesting that EPA exerts its browning effect via recruiting brite adipocytes. Consistently, long-term EPA treatment also upregulated AMPK? phosphorylation and CPT1 expression and increased glucose uptake and GLUT4 mRNA expression, suggesting improved mitochondrial oxidation. Additionally, EPA-treated adipocytes had enlarged lipid droplets and increased expression of triglyceride synthesis genes GPAT1 and GPAT3, while significantly decreased glycerol release and down-regulation of HSL and ATGL gene expression. We conclude that EPA enhances energy dissipation capacity by recruiting brite adipocytes to stimulate oxidative metabolism and reduces fatty acid release by facilitating fatty acid storage in subcutaneous adipocytes.
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Zinc finger nuclease: a new approach for excising HIV-1 proviral DNA from infected human T cells.
Mol. Biol. Rep.
PUBLISHED: 06-12-2014
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A major reason that Acquired Immune Deficiency Syndrome (AIDS) cannot be completely cured is the human immunodeficiency virus 1 (HIV-1) provirus integrated into the human genome. Though existing therapies can inhibit replication of HIV-1, they cannot eradicate it. A molecular therapy gains popularity due to its specifically targeting to HIV-1 infected cells and effectively removing the HIV-1, regardless of viral genes being active or dormant. Now, we propose a new method which can excellently delete the HIV provirus from the infected human T cell genome. First, we designed zinc-finger nucleases (ZFNs) that target a sequence within the long terminal repeat (LTR) U3 region that is highly conserved in whole clade. Then, we screened out one pair of ZFN and named it as ZFN-U3. We discovered that ZFN-U3 can exactly target and eliminate the full-length HIV-1 proviral DNA after the infected human cell lines treated with it, and the frequency of its excision was about 30 % without cytotoxicity. These results prove that ZFN-U3 can efficiently excise integrated HIV-1 from the human genome in infected cells. This method to delete full length HIV-1 in human genome can therefore provide a novel approach to cure HIV-infected individuals in the future.
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Lipocalin 2 regulates brown fat activation via a nonadrenergic activation mechanism.
J. Biol. Chem.
PUBLISHED: 06-10-2014
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In this study, we report that lipocalin 2 (Lcn2), a recently characterized adipokine/cytokine, is a novel regulator of brown adipose tissue (BAT) activation by modulating the adrenergic independent p38 MAPK-PGC-1?-UCP1 pathway. Global Lcn2 knock-out (Lcn2(-/-)) mice have defective BAT thermogenic activation caused by cold stimulation and decreased BAT activity under high fat diet-induced obesity. Nevertheless, Lcn2(-/-) mice maintain normal sympathetic nervous system activation as evidenced by normal catecholamine release and lipolytic activity in response to cold stimulation. Further studies showed that Lcn2 deficiency impairs peroxisomal and mitochondrial oxidation of lipids and attenuates cold-induced Pgc1a and Ucp1 expression and p38 MAPK phosphorylation in BAT. Moreover, in vitro studies showed that Lcn2 deficiency reduces the thermogenic activity of brown adipocytes. Lcn2(-/-) differentiated brown adipocytes have significantly decreased expression levels of brown fat markers, decreased p38 MAPK phosphorylation, and decreased mitochondrial oxidation capacity. However, Lcn2(-/-) brown adipocytes have normal norepinephrine-stimulated p38 MAPK and hormone-sensitive lipase phosphorylation and Pgc1a and Ucp1 expression, suggesting an intact ?-adrenergic signaling activation. More intriguingly, recombinant Lcn2 was able to significantly stimulate p38 MAPK phosphorylation in brown adipocytes. Activating peroxisome proliferator-activated receptor ?, a downstream effector of PGC-1?, by thiazolidinedione administration fully reverses the BAT function of Lcn2(-/-) mice. Our findings provide evidence for the novel role Lcn2 plays in oxidative metabolism and BAT activation via an adrenergic independent mechanism.
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A motif in LILRB2 critical for Angptl2 binding and activation.
Blood
PUBLISHED: 06-04-2014
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A better understanding of the interaction between extrinsic factors and surface receptors on stem cells will greatly benefit stem cell research and applications. Recently, we showed that several angiopoietin-like proteins (Angptls) bind and activate the immune inhibitory receptor human leukocyte immunoglobulin (Ig)-like receptor B2 (LILRB2) to support ex vivo expansion of hematopoietic stem cells (HSCs) and leukemia development. However, the molecular basis for the interaction between Angptls and LILRB2 was unclear. Here, we demonstrate that Angptl2 expressed in mammalian cells forms high-molecular-weight species and that ligand multimerization is required for activation of LILRB2 for downstream signaling. A novel motif in the first and fourth Ig domains of LILRB2 was identified that is necessary for the receptor to be bound and activated by Angptl2. The binding of Angptl2 to LILRB2 is more potent than and not completely overlapped with the binding of another ligand, HLA-G. Immobilized anti-LILRB2 antibodies induce a more potent activation of LILRB2 than Angptl2, and we developed a serum-free culture containing defined cytokines and immobilized anti-LILRB2 that supports a net expansion of repopulating human cord blood HSCs. Our elucidation of the mode of Angptl binding to LILRB2 enabled the development of a new approach for ex vivo expansion of human HSCs.
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Attenuation coefficients for water quality trading.
Environ. Sci. Technol.
PUBLISHED: 06-04-2014
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Water quality trading has been proposed as a cost-effective approach for reducing nutrient loads through credit generation from agricultural or point source reductions sold to buyers facing costly options. We present a systematic approach to determine attenuation coefficients and their uncertainty. Using a process-based model, we determine attenuation with safety margins at many watersheds for total nitrogen (TN) and total phosphorus (TP) loads as they transport from point of load reduction to the credit buyer. TN and TP in-stream attenuation generally increases with decreasing mean river flow; smaller rivers in the modeled region of the Ohio River Basin had TN attenuation factors per km, including safety margins, of 0.19-1.6%, medium rivers of 0.14-1.2%, large rivers of 0.13-1.1%, and very large rivers of 0.04-0.42%. Attenuation in ditches transporting nutrients from farms to receiving rivers is 0.4%/km for TN, while for TP attenuation in ditches can be up to 2%/km. A 95 percentile safety margin of 30-40% for TN and 6-10% for TP, applied to the attenuation per km factors, was determined from the in-stream sensitivity of load reductions to watershed model parameters. For perspective, over 50 km a 1% per km factor would result in 50% attenuation = 2:1 trading ratio.
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Oxaliplatin antagonizes HIV-1 latency by activating NF-?B without causing global T cell activation.
Biochem. Biophys. Res. Commun.
PUBLISHED: 05-13-2014
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Reactivation of latent HIV-1 is a promising strategy for the clearance of the viral reservoirs. Because of the limitations of current agents, identification of new latency activators is urgently required. Using an established model of HIV-1 latency, we examined the effect of Oxaliplatin on latent HIV-1 reactivation. We showed that Oxaliplatin, alone or in combination with valproic acid (VPA), was able to reactivate HIV-1 without inducing global T cell activation. We also provided evidence that Oxaliplatin reactivated HIV-1 expression by inducing nuclear factor kappa B (NF-?B) nuclear translocation. Our results indicated that Oxaliplatin could be a potential drug candidate for anti-latency therapies.
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Value of magnetic resonance imaging including dynamic contrast-enhanced magnetic resonance imaging in differentiation between inverted papilloma and malignant tumors in the nasal cavity.
Chin. Med. J.
PUBLISHED: 05-06-2014
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Distinguishing inverted papilloma (IP) from malignant tumors in the nasal cavity is difficult in a substantial number of cases, thus hindering the administration of appropriate therapeutic strategies. This study aimed to evaluate whether magnetic resonance imaging (MRI), including dynamic contrast enhanced MRI (DCE-MRI), could improve differentiation between IP and malignant tumors, and to identify which MRI features were the best in discriminating IP from malignant tumors in the nasal cavity.
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ATP release channel Pannexin1 is a novel immune response gene in Japanese flounder Paralichthys olivaceus.
Fish Shellfish Immunol.
PUBLISHED: 05-05-2014
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Extracellular ATP is an important damage-associated molecular pattern molecule that plays key roles in innate immunity. In fish, however, the mechanism for extracellular ATP release remains largely undefined. Pannexin1 (Panx1) is a newly discovered extracellular ATP release channel with a wide tissue distribution and diverse biological functions in mammals. In the present study, we identified and characterized a Panx1 homolog cDNA, termed poPanx1, from Japanese flounder Paralichthys olivaceus, which is one of the most important economic mariculture fish species in China. PoPanx1 is a membrane protein that is composed of 437 amino acids with an estimated molecular mass of 48.7 kDa and an isoelectric point of 6.46. The poPanx1 mRNA ubiquitously expresses in all examined tissues but with predominant expression in hepatopancreas in unstimulated healthy adult Japanese flounder. In Japanese flounder head kidney primary cells, poPanx1 gene expression could be significantly induced by pathogen-associated molecular patterns (PAMPs; polyinosinic-polycytidylic acid and bacterial endotoxin LPS) stimulations. In vivo experiments revealed that poPanx1 mRNA expression was significantly up-regulated upon immune challenges with Edwardsiella tarda and Vibrio anguillarum. Furthermore, we showed that poPanx1 is an important channel protein for PAMP-induced extracellular ATP release that is required for activation of purinergic signaling in fish innate immunity. Taken together, our findings suggest that the ATP release channel, poPanx1, is a novel immune response gene in purinergic signaling of Japanese flounder P. olivaceus.
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Extent of lymph node dissection: common hepatic artery lymph node dissection can be omitted for esophageal squamous cell carcinoma.
J Thorac Dis
PUBLISHED: 04-21-2014
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Controversy persists regarding the adequate extent of lymph node (LN) dissection in thoracic esophageal cancer (EC) surgery. Oncologic efficacy should be balanced with the increased risk of postoperative complications after aggressive radical LN dissection. Here, we evaluate the effectiveness of common hepatic artery LN dissection in surgery for thoracic esophageal squamous cell carcinoma.
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Elevated hydrogen sulfide levels in vitreous body and plasma in patients with proliferative diabetic retinopathy.
Retina (Philadelphia, Pa.)
PUBLISHED: 04-19-2014
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Hydrogen sulfide (H2S), a colorless gas, has been confirmed to be a gaseous messenger molecule and an endogenous stimulus for angiogenesis recently. This study was performed to investigate the role of H2S in diabetic retinopathy.
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Identification and characterization of genes differentially expressed in X and Y sperm using suppression subtractive hybridization and cDNA microarray.
Mol. Reprod. Dev.
PUBLISHED: 04-15-2014
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Differential expression of genes leads to variations in the phenotypes of X and Y sperm, although some differentially expressed gene products are shared through intercellular bridges. Genes differentially expressed in bovine X and Y sperm were identified by a combination of suppression subtractive hybridization (SSH), cDNA microarray, and sequence-homology analysis. Microarray data and Significance Analysis of Microarrays software were used to identify 31 differentially expressed genes, only four of which were previously identified. These genes are involved in fundamental life processes of mature sperm, and may be associated with the differences between X and Y sperm since 27 versus 4 were upregulated in X versus Y sperm, respectively. The levels of expression of seven genes-including the known genes UTY, DPH3, CYTB, and ISCU, and the unknown genes X?+?Y contig 41, X?+?Y contig 18, and Y?+?X contig 16-were validated by quantitative real-time PCR, and some genes were clearly differentially expressed by X and Y sperm, despite the presence of intercellular bridges among spermatids. These results provide a theoretical basis for research on gene expression during sperm development, as well as on sex control at the level of sperm. Mol. Reprod. Dev. 81: 908-917, 2014. © 2014 Wiley Periodicals, Inc.
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Dilazep synergistically reactivates latent HIV-1 in latently infected cells.
Mol. Biol. Rep.
PUBLISHED: 04-07-2014
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The long-lived latently infected cells persist in spite of prolonged highly active anti-retroviral therapy and present a major barrier to a cure of human immunodeficiency virus type 1 (HIV-1) infection. Elimination of this reservoir requires reactivation of the latent virus. None of the current agents can safely and effectively reactivate latent HIV-1 reservoirs. Dilazep, a nucleoside transport inhibitor, is used to treat ischemic dysfunction. However, little is known about the effect of dilazep in inducing HIV expression in latently infected cells. Using the Jurkat T cell model of HIV-1 latency, we found that dilazep effectively reactivates latent HIV-1 gene expression in a dose manner. We observed that dilazep synergistically reactivated latent HIV-1 transcription with valproic acid. We also found that dilazep activates viral latency without inducing cell surface activation markers CD25 and CD69 activation. In summary, dilazep, alone or in combination with VPA, could be useful in future eradication strategies.
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The regulatory role of immunosuppressants on immune abnormalities in acute pancreatitis.
Biomed Rep
PUBLISHED: 03-21-2014
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The uncontrolled progression of the inflammatory cascade is the main cause underlying the development of multiple organ dysfunction syndrome (MODS) in acute pancreatitis. In this study, we investigated the effects of several immunosuppressants on mitigating the systemic inflammatory reaction syndrome (SIRS) and the compensatory anti-inflammatory response syndrome (CARS) associated with acute pancreatitis. A total of 93 male Sprague Dawley rats were divided into 5 groups: group 1 was the sham group and group 2 underwent laparoscopic intrapancreatic duct injection of sodium taurocholate to induce pancreatitis. The remaining 3 groups were the same as group 2, with the addition of methylprednisolone, cyclophosphamide or methotrexate treatment (metastab, CTX or MTX groups, respectively). Following establishment of the acute pancreatitis model, the serum levels of inflammatory and anti-inflammatory cytokines in groups 2, 3, 4 and 5 were found to be significantly elevated. Following immunosuppressant administration, the levels of all inflammatory and anti-inflammatory cytokines investigated in groups 3, 4 and 5 were decreased compared to those in group 2. The pancreatic amylase levels and pancreatic wet weight (PWW) were also decreased in groups 3, 4 and 5 compared to those in group 2. Therefore, immunosuppressants may reduce inflammation-related cytokine levels in acute pancreatitis and relieve disease progression.
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A cross-sectional study of risk factors for irritable bowel syndrome in children 8-13 years of age in suzhou, china.
Gastroenterol Res Pract
PUBLISHED: 03-09-2014
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To determine the prevalence and risk factors of IBS in children 8-13 years of age in Suzhou city, a cross-sectional study was conducted on children in grades 1 through 6 in public elementary schools in three districts of Suzhou. A multistage stratified random-sampling survey was conducted in a primary investigation using standardized questionnaires. Rome II criteria were used to confirm IBS and their risk factors were analyzed. Of 8,000 questionnaires 7,472 responded satisfactorily for a response rate of 93.4%. IBS was diagnosed in 10.81%. A decrease in the prevalence of IBS was significantly associated with advancing age and grade in school (trend test, P < 0.05). The prevalence of IBS in females was higher but not significantly different than males. The significant risk factors for IBS included young age (OR = 0.94), food allergy (OR = 1.53), gastroenteritis during childhood (OR = 1.29), eating fried food (OR = 1.62), anxiety (OR = 1.49), psychological insults in early childhood (OR = 1.47), and parental history of constipation (OR = 1.81; all P < 0.05). IBS prevalence of 10.81% in study population warrants preventive measures such as encouraging dietary changes, preventing gastroenteritis and childhood psychological insults.
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[A novel histological typing and grading-scale system of colorectal cancer].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 03-05-2014
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To formulate a novel histological typing and grading-rated system for colorectal cancer (CRC) for evaluating the biological behavior of CRC and prognosis.
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A monoclonal antibody targeting neuropilin-1 inhibits adhesion of MCF7 breast cancer cells to fibronectin by suppressing the FAK/p130cas signaling pathway.
Anticancer Drugs
PUBLISHED: 03-04-2014
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Neuropilin-1 (NRP-1) is a nontyrosine kinase coreceptor for semaphorin 3A and the vascular endothelial growth factor involved in tumor angiogenesis, growth, and metastasis and is regarded as a promising target for cancer therapy. In the present study, we investigated the effects of an anti-NRP-1 monoclonal antibody (mAb) that we generated for MCF7 breast cancer cellular adhesion studies. MTT, colony formation, and adhesion assays showed that our anti-NRP-1 mAb dose-dependently inhibited MCF7 proliferation and fibronectin adhesion, leading to a rounded cellular morphology. Further, rhodamine phalloidin stain revealed that fibronectin-dependent formation of actin stress fibers was inhibited by anti-NRP-1 mAb. Immunoprecipitation and western blot showed that anti-NRP-1 mAb treatment inhibited the formation of NRP-1-?5?1 integrin complexes and suppressed the phosphorylation of focal adhesion kinase and p130cas in MCF7 cells. These findings contribute to further understanding the NRP-1 function in cell adhesion and tumor metastasis. Moreover, our anti-NRP-1 mAb is a prospective drug candidate for tumor treatment.
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Thermoresponsive worms for expansion and release of human embryonic stem cells.
Biomacromolecules
PUBLISHED: 02-26-2014
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The development of robust suspension cultures of human embryonic stem cells (hESCs) without the use of cell membrane disrupting enzymes or inhibitors is critical for future clinical applications in regenerative medicine. We have achieved this by using long, flexible, and thermoresponsive polymer worms decorated with a recombinant vitronectin subdomain that bridge hESCs, aiding in hESC's natural ability to form embryoid bodies (EBs) and satisfying their inherent requirement for cell-cell and cell-extracellular matrix contact. When the EBs reached an optimal upper size where cytokine and nutrient penetration becomes limiting, these long and flexible polymer worms facilitated EB breakdown via a temperature shift from 37 to 25 °C. The thermoresponsive nature of the worms enabled a cyclical dissociation and propagation of the cells. Repeating the process for three cycles (over eighteen days) provided a >30-fold expansion in cell number while maintaining pluripotency, thereby providing a simple, nondestructive process for the 3D expansion of hESC.
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Semiconductor alloy nanoribbon lateral heterostructures for high-performance photodetectors.
Adv. Mater. Weinheim
PUBLISHED: 02-21-2014
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High-performance visible-light photodetectors are achieved based on single nanoribbon lateral heterostructures composed of two different semiconductor alloys epitaxially grown in the lateral direction. They reveal superior spectral response range, responsivity, Ion/Ioff ratio, and external quantum efficiency, relative to devices based on single composition structures.
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Associations of allostatic load with sleep apnea, insomnia, short sleep duration, and other sleep disturbances: findings from the National Health and Nutrition Examination Survey 2005 to 2008.
Ann Epidemiol
PUBLISHED: 02-18-2014
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To examine whether allostatic load (AL), a measure of cumulative physiologic dysregulation across biological systems, was associated with sleep apnea, insomnia, and other sleep disturbances.
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Different efficacy of EGFR tyrosine kinase inhibitors and prognosis in patients with subtypes of EGFR-mutated advanced non-small cell lung cancer: a meta-analysis.
J. Cancer Res. Clin. Oncol.
PUBLISHED: 02-16-2014
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Nearly 85 % of lung-cancer-specific epidermal growth factor receptor (EGFR) sensitive mutations comprise a substitution at position 858 (21L858R) and deletion mutants in exon 19 (19del). The aim of this study was to assess the role of EGFR mutation subtypes in predicting the efficacy of EGFR tyrosine kinase inhibitors (EGFR TKIs) and the prognosis of patients with advanced non-small cell lung cancer (NSCLC).
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The application of functional magnetic resonance imaging in an infant rat model of irritable bowel syndrome.
Gastroenterol Res Pract
PUBLISHED: 02-13-2014
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The aim of this study was to use functional magnetic resonance imaging (BOLD-fMRI) to investigate the activated region associated with visceral pain in the brains of infant rats in a model of IBS. Sixteen newborn rats were randomized into an IBS model group and a control group. Those in the IBS group were separated from their mothers and were mechanically immobilized and had rectal sensitization with mustard essential oil for 1 week. The control group had no treatment. After 2 weeks, balloon catheters were inflated with 5 or 10?mL of air in the rectums of both groups. BOLD-fMRI was performed and the data analyzed by imaging software. In the IBS model group, rectal stimulation with 5?mL air distension activated the anterior cingulate cortex, insula cortex (IC), prefrontal cortex (PFC), and thalamus, while 10?mL air significantly activated the ACC, IC, PFC, and thalamus in the model, but not controls. IBS model group was hypersensitive to visceral stimulation by rectal balloon inflation. The major brain areas participating in visceral sensation included the IC, PFC, and thalamus.
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Global deletion of lipocalin 2 does not reverse high-fat diet-induced obesity resistance in stearoyl-CoA desaturase-1 skin-specific knockout mice.
Biochem. Biophys. Res. Commun.
PUBLISHED: 02-05-2014
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Over the past century, obesity has developed into a paramount health issue that affects millions of people worldwide. Obese individuals have an increased risk to develop other metabolic disorders, such as insulin resistance and atherosclerosis, among others. Previously we determined that mice lacking stearoyl-CoA desaturase-1 (SCD1) enzyme specifically in the skin (SKO) were lean and protected from high-fat diet induced adiposity. Additionally, lipocalin 2 (Lcn2) mRNA was found to be 27-fold higher in the skin of SKO mice compared to control mice. Given reports suggesting that Lcn2 plays a role in protection against diet-induced weight gain, adiposity and insulin resistance, we hypothesized that deletion of Lcn2 alongside the skin-specific SCD1 deficiency would diminish the obesity resistance observed in SKO mice. To test this, we developed mice lacking SCD1 expression in the skin and also lacking Lcn2 expression globally and surprisingly, these mice did not gain significantly more weight than the SKO mice under high-fat diet conditions. Therefore, we conclude that Lcn2 does not mediate the protection against high-fat diet-induced adiposity observed in SKO mice.
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Angiographic features of ruptured sinus of Valsalva aneurysm: new classification.
J Cardiol
PUBLISHED: 02-01-2014
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The formal classification system for ruptured sinus of Valsalva aneurysm (RSVA) is from a surgical aspect and is seldom utilized for percutaneous closure. This study was undertaken to introduce a new classification for RSVA according to the angiographic features of patients.
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Adult limbal neurosphere cells: a potential autologous cell resource for retinal cell generation.
PLoS ONE
PUBLISHED: 01-01-2014
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The Corneal limbus is a readily accessible region at the front of the eye, separating the cornea and sclera. Neural colonies (neurospheres) can be generated from adult corneal limbus in vitro. We have previously shown that these neurospheres originate from neural crest stem/progenitor cells and that they can differentiate into functional neurons in vitro. The aim of this study was to investigate whether mouse and human limbal neurosphere cells (LNS) could differentiate towards a retinal lineage both in vivo and in vitro following exposure to a developing retinal microenvironment. In this article we show that LNS can be generated from adult mice and aged humans (up to 97 years) using a serum free culture assay. Following culture with developing mouse retinal cells, we detected retinal progenitor cell markers, mature retinal/neuronal markers and sensory cilia in the majority of mouse LNS experiments. After transplantation into the sub-retinal space of neonatal mice, mouse LNS cells expressed photoreceptor specific markers, but no incorporation into host retinal tissue was seen. Human LNS cells also expressed retinal progenitor markers at the transcription level but mature retinal markers were not observed in vitro or in vivo. This data highlights that mouse corneal limbal stromal progenitor cells can transdifferentiate towards a retinal lineage. Complete differentiation is likely to require more comprehensive regulation; however, the accessibility and plasticity of LNS makes them an attractive cell resource for future study and ultimately therapeutic application.
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The Relationship between High Risk for Obstructive Sleep Apnea and General and Central Obesity: Findings from a Sample of Chilean College Students.
ISRN Obes
PUBLISHED: 01-01-2014
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This cross-sectional study evaluates the prevalence and extent to which high risk for obstructive sleep apnea (OSA) is associated with general obesity and central obesity among college students in Punta Arenas, Chile. Risk for OSA was assessed using the Berlin Questionnaire and trained research nurses measured anthropometric indices. Overweight was defined as body mass index (BMI) of 25-29.9?kg/m(2) and general obesity was defined as BMI ? 30?kg/m(2). Central obesity was defined as waist circumference ?90 centimeters (cm) for males and ?80?cm for females. Multivariate logistic regression models were fit to obtain adjusted odds ratios (OR) and 95% confidence intervals (CI). Prevalence of high risk for OSA, general obesity, and central obesity were 7.8%, 12.8%, and 42.7%, respectively. Students at high risk for OSA had greater odds of general obesity (OR 9.96; 95% CI: 4.42-22.45) and central obesity (OR 2.78; 95% CI 1.43-5.40). Findings support a strong positive association of high risk for OSA with obesity.
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A new method to assay protease based on amyloid misfolding: application to prostate cancer diagnosis using a panel of proteases biomarkers.
Theranostics
PUBLISHED: 01-01-2014
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This paper reports a sensitive method with electrochemical technique to detect various proteases, which can be used for the diagnosis of prostate cancer. For the proposed assay method, the working electrode is modified with the peptide probes for the target proteases. These probes contain the substrate sequence of target proteases, as well as the seed peptide sequence that can accelerate the misfolding of amyloid-beta. If there are proteases in the test solution, after protease cleavage of the substrate peptides, the distal seed peptide will be removed from the electrode surface. So, in the absence of proteases, the seed peptides can initiate and accelerate amyloid-beta misfolding on the electrode surface. Consequently, the formed aggregates strongly block the electron transfer of the in-solution electroactive species with the electrode, resulting in suppressed signal readout. Nevertheless, in the presence of proteases, enzyme cleavage may lead to greatly mitigated protein misfolding and evident signal enhancement. Since the contrast in signal readout between the two cases can be amplified by using the protein misfolding step, high sensitivity suitable for direct detection of proteases in serum can be achieved. These results may suggest the feasibility of our new method for the detection of a panel of proteases in offering detailed diagnosis of prostate cancer and a better treatment of the cancer.
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Lipocalin 2 expression and secretion is highly regulated by metabolic stress, cytokines, and nutrients in adipocytes.
PLoS ONE
PUBLISHED: 01-01-2014
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Lipocalin 2 (Lcn2) has been recently characterized as a new adipokine having a role in innate immunity and energy metabolism. Nonetheless, the metabolic regulation of Lcn2 production in adipocytes has not been comprehensively studied. To better understand the Lcn2 biology, we investigated the regulation of Lcn2 expression in adipose tissue in response to metabolic stress in mice as well as the control of Lcn2 expression and secretion by cytokines and nutrients in 3T3-L1 adipocytes. Our results showed that the mRNA expression of Lcn2 was upregulated in white and brown adipose tissues as well as liver during fasting and cold stress in mice. Among pro-inflammatory cytokines TNF?, IL-1?, and IL-6, IL-1? showed most profound effect on Lcn2 expression and secretion in 3T3-L1 adipocytes. Insulin stimulated Lcn2 expression and secretion in a dose-dependent manner; this insulin effect was significantly abolished in the presence of low concentration of glucose. Moreover, insulin-stimulated Lcn2 expression and secretion was also attenuated when glucose was replaced by 3-O-methyl-d-glucose or by blocking NF?B pathway activation. Additionally, we showed that palmitate and oleate induced Lcn2 expression and secretion more significantly than EPA, while phytanic acid reduced Lcn2 production. Our results demonstrated that Lcn2 production in adipocytes is highly responsive to metabolic stress, cytokines, and nutrient signals, suggesting an important role of Lcn2 in adipocyte metabolism and inflammation.
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Timing of tracheostomy in critically ill patients: a meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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To compare important outcomes between early tracheostomy (ET) and late tracheostomy (LT) or prolonged intubation (PI) for critically ill patients receiving long-term ventilation during their treatment.
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High risk for obstructive sleep apnea in relation to hypertension among southeast asian young adults: role of obesity as an effect modifier.
Am. J. Hypertens.
PUBLISHED: 10-16-2013
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Obstructive sleep apnea (OSA) has been linked to hypertension among middle-aged and older adults in Western countries. Few studies have focused on young adults, especially those in Southeast Asian countries undergoing epidemiologic transitions and experiencing elevated noncommunicable disease burden. We investigated associations of high risk for OSA with hypertension among Asian young adults.
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Highly sensitive protein detection based on a novel probe with catalytic activity combined with a signal amplification strategy: assay of MDM2 for cancer staging.
Chem. Commun. (Camb.)
PUBLISHED: 09-14-2013
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A novel probe with catalytic activity is used for highly sensitive MDM2 detection.
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Perspectives on disconnects between scientific information and management decisions on post-fire recovery in Western US.
Environ Manage
PUBLISHED: 09-06-2013
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Environmental regulations frequently mandate the use of "best available" science, but ensuring that it is used in decisions around the use and protection of natural resources is often challenging. In the Western US, this relationship between science and management is at the forefront of post-fire land management decisions. Recent fires, post-fire threats (e.g. flooding, erosion), and the role of fire in ecosystem health combine to make post-fire management highly visible and often controversial. This paper uses post-fire management to present a framework for understanding why disconnects between science and management decisions may occur. We argue that attributes of agencies, such as their political or financial incentives, can limit how effectively science is incorporated into decision-making. At the other end of the spectrum, the lack of synthesis or limited data in science can result in disconnects between science-based analysis of post-fire effects and agency policy and decisions. Disconnects also occur because of the interaction between the attributes of agencies and the attributes of science, such as their different spatial and temporal scales of interest. After offering examples of these disconnects in post-fire treatment, the paper concludes with recommendations to reduce disconnects by improving monitoring, increasing synthesis of scientific findings, and directing social-science research toward identifying and deepening understanding of these disconnects.
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A rhodamine-based fluorescent probe for detecting Hg(2+) in a fully aqueous environment.
Dalton Trans
PUBLISHED: 08-30-2013
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A water-soluble fluorescent probe for Hg(2+) based on a rhodamine B derivative was designed and synthesized. The new probe showed reversible colorimetric and fluorescent response to Hg(2+) in a fully aqueous solution. The probe exhibited real-time detection of Hg(2+) with high selectivity in media containing less than 1% organic cosolvent. Furthermore, bioimaging studies indicated that the new probe was cell permeable and suitable for the real-time imaging of Hg(2+) in living cells by confocal microscopy.
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IGF binding protein 2 is a cell-autonomous factor supporting survival and migration of acute leukemia cells.
J Hematol Oncol
PUBLISHED: 08-29-2013
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The role of IGF binding protein 2 (IGFBP2) in cancer development is intriguing. Previously we identified IGFBP2 as an extrinsic factor that supports the activity of hematopoietic stem cells (HSCs).
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Chemical analysis and antioxidant activity of polysaccharides extracted from Inonotus obliquus sclerotia.
Int. J. Biol. Macromol.
PUBLISHED: 08-25-2013
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Three water-soluble polysaccharide fractions (IOP40, IOP60 and IOP80) were isolated by using different concentrations of alcohol precipitation from Inonotus obliquus sclerotia. Their physicochemical properties, including total sugar content, protein content, monosaccharide composition and percentage were analyzed. And their in vitro antioxidant capacities were investigated in terms of reducing power assay and scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, hydroxyl radicals, superoxide anion radicals and hydrogen peroxide (H2O2). In general, three polysaccharide fractions exhibited increasing antioxidant activity with increasing concentration at the ranges of tested dosage. The orders of reducing power, DPPH-scavenging capacity, H2O2-scavenging capacity, and hydroxyl-scavenging activity were all IOP60>IOP40>IOP80. These findings demonstrated that three polysaccharide fractions extracted from I. obliquus, especially IOP60, could be employed as natural ingredients in functional food and pharmaceutical industry to alleviate the oxidative stress.
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A monoclonal antibody produced against Naked2.
Monoclon Antib Immunodiagn Immunother
PUBLISHED: 08-06-2013
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Naked2 (NKD2) is a member of the Naked family and negatively regulates canonical Wnt signaling. NKD2 may play a role in embryo development and tumor formation by affecting Wnt signaling. In the present study, we describe the establishment of a monoclonal antibody against NKD2 (anti-NKD2 MAb) through the hybridoma method. The purified anti-NKD2 MAb measured a titer of 2.56 × 10(5) against NKD2 by indirect ELISA. Western blot analysis, immunoprecipitation, and confocal microscope showed that the anti-NKD2 MAb can specifically combine NKD2 protein in SW480 and LOVO cells. Competitive inhibition assays of Western blot and indirect ELISA showed that the anti-NKD2 MAb can be blocked with NKD2(1-217) protein. The anti-NKD2 MAb would be helpful for further studies on the structure activity relationship, protein detecting, and cell-signaling pathway of NKD2.
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Fabrication of a protease sensor for caspase-3 activity detection based on surface plasmon resonance.
Analyst
PUBLISHED: 08-03-2013
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Diagnosis of apoptosis is essential to the early detection of therapy efficiency and the evaluation of disease progression. Caspase-3 is supposed to be closely related to cellular apoptosis. We describe here a label-free surface plasmon resonance (SPR) detection of apoptosis based on caspase-3 activity assay through enzyme digestion. An artificial peptide sequence was designed as a substrate of caspase-3 and immobilized on a gold disk through covalent binding. The 4Lys part at the end of the pentadecyl-peptide was designed to form a unique peptide array through electrostatic repulsion. The immobilization of the peptide on the gold surface was carefully characterized by SPR and atomic force microscopy. The catalytic conditions of caspase-3 were optimized with electrochemical impedance spectroscopy. The detection limit of caspase-3 was found at a concentration of 1 pg mL(-1). The activity of caspase-3 in apoptotic cells could also be measured sensitively by the one-step and intuitional SPR response decrease. The fabricated simple and convenient caspase-3 sensor is proposed for application in clinical analysis.
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Quasi-periodic gratings: diffraction orders accelerate along curves.
Opt Lett
PUBLISHED: 08-02-2013
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Light diffracting to different diffraction orders of a periodic grating generally propagates along a set of straight trajectories. Here we show that certain quasi-periodic gratings can produce curved diffraction orders. These curved lobes are created by the caustic interference of the originally straight diffraction orders and manifest themselves as accelerating beams. Both numerical simulations and experimental results demonstrate the validity of multiple accelerating beam generation with a single binary grating. Our work makes a quantitative link between the quasi-periodicity of a grating and the resulting caustic diffraction orders. Furthermore, the use of binary devices has important applications in acoustics, x-ray optics, and electron beam engineering and is also useful when high optical power is needed.
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Inhibition of ROCK-Myosin II Signaling Pathway Enables Culturing of Human Pluripotent Stem Cells on Microcarriers Without Extracellular Matrix Coating.
Tissue Eng Part C Methods
PUBLISHED: 07-25-2013
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Large quantities of human pluripotent stem cells (hPSCs) needed for therapeutic applications can be grown in scalable suspended microcarrier cultures. These microcarriers are coated with animal or human extracellular matrix (ECM) proteins to promote cell growth and maintain pluripotency. However, the coating is costly for large-scale cultures and it presents safety risks. This study demonstrates that hPSCs can be propagated on noncoated positively charged cellulose microcarriers in a serum-free medium containing the ROCK inhibitor, (Y27632) or myosin inhibitor, Blebbistatin. In the presence of these two inhibitors, myosin phosphatase 1 and myosin light chain 2 were dephosphorylated suggesting that reduced myosin contractility is responsible for hPSC survival and growth on ECM coating-free microcarriers. Cells propagated on the noncoated microcarriers for 12 passages maintained their pluripotency and karyotype stability. Scalability was demonstrated by achieving a cell concentration of 2.3×10(6) cells/mL with 11.5-fold expansion (HES-3) in a 100-mL spinner flask. The differentiation capability of these cells toward three primary lineages is demonstrated via in vitro embryoid bodies and in vivo teratoma formations. Moreover, the directed differentiation to polysialylated neuronal cell adhesion molecule-positive (PSA-NCAM+) neural progenitors produced high cell concentrations (9.1±1.2×10(6) cells/mL) with a cell yield of 412±77 neural progenitor cells per seeded HES-3 and a PSA-NCAM expression level of 91±1.1%. This defined serum- and coating-free scalable microcarrier culturing system is a safer and less expensive method for generating large amounts of hPSCs for cell therapies.
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Electrochemical assay of the relationship between the inhibition of phosphatidylinositol 3-kinase pathway and estrogen receptor expression in breast cancer.
Anal Bioanal Chem
PUBLISHED: 07-24-2013
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Breast cancer has become one of the most threatening diseases to women throughout the world. Emerging evidence implies that estrogen receptor (ER) and phosphatidylinositol 3-kinase (PI3K) pathways play central roles in both breast cancer progression and response to therapy. In this work, we have probed into ER expression related to the PI3K pathway at the protein level with an electrochemical technique based on the detection of ER proteins in nuclear extracts with an Exonuclease III protection-based strategy. Experimental results show that an increased number of ER proteins can be detected upon PI3K inhibition, demonstrating the reversal effect of the PI3K inhibitor on ER expression. Moreover, treatment with different concentrations of the PI3K inhibitor NVP-BEZ235 can result in a dose-dependent alteration of ER protein levels, implying an intimate link between ER and PI3K pathways. This work may be a great help to understand the mysteries underlying PI3K-related endocrine resistance and to evaluate the effect of therapeutic interventions in the future.
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Granulocyte Colony-Stimulating Factor Administration for Infertile Women With Thin Endometrium in Frozen Embryo Transfer Program.
Reprod Sci
PUBLISHED: 07-24-2013
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We aimed to evaluate the effectiveness of granulocyte colony-stimulating factor (G-CSF) administration for infertile women with thin endometrium in frozen embryo transfer program. Among 59 infertile patients with thin endometrium (?7 mm), 34 patients received uterine infusion of recombinant human G-CSF (100 ?g/0.6 mL) on the day of ovulation or administration of progesterone or human chorionic gonadotropin, with 40 cycles defined as G-CSF group and 49 previous cycles as self-controlled group, and 25 patients refused, with 80 cycles defined as the control group. Higher proportion of induced cycles and lower proportion of natural cycles were observed in the G-CSF group, when compared to the self-controlled group or control group (P < .05). The cycle cancellation rate was, in descending order, 69.39% in self-controlled group, 48.75% in control group, and 17.50% in G-CSF group, with significant difference (P < .05). The implantation rate and clinical pregnancy rate per embryo transfer were similar in all the groups (P > .05). Our study fails to demonstrate that G-CSF has the potential to improve embryo implantation and clinical pregnancy rate of the infertile women with thin endometrium.
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Evidence for the regulatory role of lipocalin 2 in high-fat diet-induced adipose tissue remodeling in male mice.
Endocrinology
PUBLISHED: 07-24-2013
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Lipocalin 2 (Lcn2) has previously been characterized as an adipokine/cytokine playing a role in glucose and lipid homeostasis. In this study, we investigate the role of Lcn2 in adipose tissue remodeling during high-fat diet (HFD)-induced obesity. We find that Lcn2 protein is highly abundant selectively in inguinal adipose tissue. During 16 weeks of HFD feeding, the inguinal fat depot expanded continuously, whereas the expansion of the epididymal fat depot was reduced in both wild-type (WT) and Lcn2(-/-) mice. Interestingly, the depot-specific effect of HFD on fat mass was exacerbated and appeared more pronounced and faster in Lcn2(-/-) mice than in WT mice. In Lcn2(-/-) mice, adipocyte hypertrophy in both inguinal and epididymal adipose tissue was more profoundly induced by age and HFD when compared with WT mice. The expression of peroxisome proliferator-activated receptor-? protein was significantly down-regulated, whereas the gene expression of extracellular matrix proteins was up-regulated selectively in epididymal adipocytes of Lcn2(-/-) mice. Consistent with these observations, collagen deposition was selectively higher in the epididymal, but not in the inguinal adipose depot of Lcn2(-/-) mice. Administration of the peroxisome proliferator-activated receptor-? agonist rosiglitazone (Rosi) restored adipogenic gene expression. However, Lcn2 deficiency did not alter the responsiveness of adipose tissue to Rosi effects on the extracellular matrix expression. Rosi treatment led to the further enlargement of adipocytes with improved metabolic activity in Lcn2(-/-) mice, which may be associated with a more pronounced effect of Rosi treatment in reducing TGF-? in Lcn2(-/-) adipose tissue. Consistent with these in vivo observations, Lcn2 deficiency reduces the adipocyte differentiation capacity of stromal-vascular cells isolated from HFD-fed mice in these cells. Herein Rosi treatment was again able to stimulate adipocyte differentiation to a similar extent in WT and Lcn2(-/-) inguinal and epididymal stromal-vascular cells. Thus, combined, our data indicate that Lcn2 has a depot-specific role in HFD-induced adipose tissue remodeling.
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Effect of delayed initiation of gonadotropin in luteal long protocol on in vitro fertilization.
Gynecol. Endocrinol.
PUBLISHED: 07-18-2013
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To evaluate whether delayed initiation of gonadotropin in luteal long protocol affected the outcome of in vitro fertilization (IVF).
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Sleep characteristics and health-related quality of life among a national sample of American young adults: assessment of possible health disparities.
Qual Life Res
PUBLISHED: 07-10-2013
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The aim of the study is to examine the associations of sleep characteristics with health-related quality of life (HRQOL) and sleep health disparities among US young adults using national survey data.
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DNA-templated silver nanoclusters based label-free fluorescent molecular beacon for the detection of adenosine deaminase.
Biosens Bioelectron
PUBLISHED: 06-13-2013
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A general and reliable fluorescent molecular beacon is proposed in this work utilizing DNA-templated silver nanoclusters (AgNCs). The fluorescent molecular beacon has been employed for sensitive determination of the concentration of adenosine deaminase (ADA) and its inhibition. A well-designed oligonucleotide containing three functional regions (an aptamer region for adenosine assembly, a sequence complementary to the region of the adenosine aptamer, and an inserted six bases cytosine-loop) is adopted as the core element in the strategy. The enzymatic reaction of adenosine catalyzed by ADA plays a key role as well in the regulation of the synthesis of the DNA-templated AgNCs, i.e. the signal indicator. The intensity of the fluorescence signal may thereby determine the concentration of the enzyme and its inhibitor. The detection limit of the ADA can be lowered to 0.05 UL(-1). Also, 100 fM of a known inhibitor erythro-9-(2-hydroxy-3-nonyl) adenine hydrochloride (EHNA) is enough to present distinguishable fluorescence emission. Moreover, since the fluorescent signal indicator is not required to be bound with the oligonucleotide, this fluorescent molecular beacon may integrate the advantages of both the label-free and signal-on strategies.
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Combination of low-dose mycophenolate mofetil with cyclosporine and methotrexate as GVHD prophylaxis in unrelated donor allogeneic stem cell transplantation.
Leuk. Res.
PUBLISHED: 06-11-2013
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We report the results of HLA-matched unrelated donor allogeneic stem cell transplantation with new GVHD prophylaxis regimen consisted of cyclosporine, methotrexate and low-dose mycophenolate mofetil in 139 patients with hematologic malignancies. The incidence of grades II-IV and III-IV acute GVHD were 43.0% and 17.3%, respectively. The incidence of chronic GVHD was 42.1%, with 16.5% extensive grade. The cumulative incidence of transplant-related mortality at 100 days and 3 years were 7.9% and 29.7%, respectively. Three-year overall survival, disease-free survival and relapse incidence were 58.7%, 55.3% and 19.6%, respectively. These results suggest the new regime may be effective for the prophylaxis of acute and chronic GVHD in unrelated donor transplantation.
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Isolation and characterization of a Chinese strain of Tembusu virus from Hy-Line Brown layers with acute egg-drop syndrome in Fujian, China.
Arch. Virol.
PUBLISHED: 06-09-2013
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Tembusu virus (TMUV) has been a causative agent of an acute egg-drop syndrome found in Chinese duck populations since at least 2010. In this paper, we report the characterization of a TMUV-like flavivirus (named CJD05) isolated from naturally infected egg-laying fowl. The virus was identified and then isolated from hens suffering from severe egg drop and fever in Fujian Province, China. The virus replicated well in MDEF and CEF cells, and its cytopathogenic effect (CPE) was apparent. Hemagglutinating activity (HA) was negative for this virus using erythrocytes from both chickens and pigeons. Viral particles were enveloped and approximately 45 nm in diameter, as observed by electron microscopy. Phylogenetic analysis of the full-length nucleotide sequence of CJD05 indicated that this virus is closely related to the duck-origin TMUV, belonging to Ntaya group of flavivirus. Most importantly, pathogenicity studies showed that CJD05 is highly virulent in 1-day-old chicks, 1-day-old Muscovy ducks, egg-laying chickens and shelducks. Our research highlights the increase in epidemic disease caused by avian TMUV, and subsequent outbreaks are becoming more complicated to treat. The pathogenic mechanisms of the virus are still not fully understood, further research is needed.
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Involvement of cathepsins B and L in inflammation and cholesterol trafficking protein NPC2 secretion in macrophages.
Obesity (Silver Spring)
PUBLISHED: 05-13-2013
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Obesity and its related chronic inflammation are the major risk factors for developing metabolic disturbances. The roles of cathepsin cysteine proteases have been tied to inflammation and atherosclerosis. Cathepsins are important functional links between inflammation, cholesterol metabolism, and atherosclerosis in obesity. NPC2, a lysosomal protein, plays an important role in cholesterol trafficking. The objective of this study was to examine the regulation of cathepsins and NPC2 in adipose tissue and macrophages in obesity and the effect of modifying cathepsin activity in cholesterol metabolism and trafficking in macrophages.
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Prognostic role of epidermal growth factor receptor in head and neck cancer: a meta-analysis.
J Surg Oncol
PUBLISHED: 04-19-2013
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To evaluate the predicting value of the epidermal growth factor receptor (EGFR) for survival in patients with head and neck cancer (HNC).
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A new electrochemical method for the detection of cancer cells based on small molecule-linked DNA.
Biosens Bioelectron
PUBLISHED: 04-10-2013
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Sensitive and accurate detection of cancer cells plays a crucial role in clinical diagnosis, treatment and prognosis of tumors. In this paper, we report a new electrochemical method for highly selective and sensitive detection of cancer cells by using small molecule-linked DNA as probes. The methodology is based on the fact that exonuclease I can catalyze the digestion of folate-linked DNA probes that are immobilized on an electrode surface; however, in the presence of the target cells, such as human breast cancer MCF-7 cells, the probes can be protected from digestion upon the binding with folate receptor that is over-expressed on the cell surface. Consequently, cancer cells can be efficiently detected by monitoring the status of the probe DNA with electrochemical techniques. In this study, the protection to exonuclease I-catalyzed digestion has also been proven by electrochemical studies. Moreover, the proposed method has been proven to linearly detect MCF-7 cells in a wide range from 10(2)-10(6) cell mL(-1) with a low detection limit of 67 cell mL(-1), which can also easily distinguish the folate receptor-negative normal cells, for instance, islet ? cells. The reproduction of the detection is also satisfactory, since the relative standard deviations for three independent measurements of different concentration of MCF-7 cells are all within 10%. By replacing the small molecules linked on the DNA probe, other cancer cells can also be detected by making use of this proposed method. Therefore, our cytosensor may have great potential in clinical applications.
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Effects of vegetation cover of natural grassland on runoff and sediment yield in loess hilly region of China.
J. Sci. Food Agric.
PUBLISHED: 03-26-2013
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The effects of vegetation cover (VC) on runoff and sediment yield were investigated from rainfall simulation experiments in the Loess Plateau of China. Five VCs from 0% to 80% and three different rainfall intensities (I2.0, 1.5, 0.75 ) were implemented.
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Significant association between asthma risk and the GSTM1 and GSTT1 deletion polymorphisms: an updated meta-analysis of case-control studies.
Respirology
PUBLISHED: 03-12-2013
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Polymorphisms in GSTM1 and GSTT1 may be associated with asthma risk, yet several studies and meta-analyses have reported inconclusive results. Therefore, an updated meta-analysis was conducted. Literature searches were performed using the Pubmed, Embase and Web of Science databases until October 2012. Variant null genotype was compared with wild-type present in the pooled data. All statistical analyses were performed using STATA 11.0. A total of 26 case-control studies were suitable for inclusion in the meta-analysis. In the overall population, a significant association was found for both the GSTM1 (odds ratio (OR)?=?1.452; 95% confidence interval (CI): 1.192-1.770) and GSTT1 polymorphism (OR?=?1.792; 95% CI:1.293-2.483). For subgroup analysis by age, GSTM1 significantly increased risk for both children (OR?=?1.368; 95% CI: 1.051-1.781) and adults (OR?=?1.859; 95% CI: 1.183-2.921). For GSTT1, a significant association was only found in the adult population (OR?=?2.312; 95%CI: 1.204-4.439). Based on subgroup analysis by ethnicity, a significant association for GSTM1 was found in Europe (OR?=?1.303; 95% CI: 1.018-1.667), Africa (OR?=?2.175; 95%CI: 1.560-3.031) and Latin America (OR?=?2.265; 95%CI: 1.375-3.729). For GSTT1, significantly increased risk was found only for Asian (OR?=?2.105; 95% CI: 1.101-4.025) and Russian (OR?=?2.747; 95% CI: 1.071-7.046) populations. This meta-analysis provides evidence that GSTM1 and GSTT1 polymorphisms may be risk factors for asthma.
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An aggressive form of non-Hodgkins lymphoma with pleural and abdominal chylous effusions: A case report and review of the literature.
Oncol Lett
PUBLISHED: 03-10-2013
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Serous effusions, including pleural, abdominal and pericardial effusions, are complications of lymphoma. Among these types, pleural effusions are the most common to be observed. However, the involvement of the abdominal or pericardial cavity is rare. An impairment of the lymphatic drainage and direct infiltration have been identified to play significant roles in effusion formation. Multiple techniques, including cytological exams, immunochemistry and cytogenetics, have been applied in the clinic to access the qualities of the effusions and to attain a fast and precise diagnosis. Serous effusions are associated with a poor outcome for patients with lymphoma. The present study describes the case of a 28-year-old male patient with aggressive non-Hodgkins lymphoma (NHL) involving pleural and abdominal chylous effusions.
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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.

How does it work?

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

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

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