297 research outputs found

    HIPK2 reduces the resistance of gastric cancer cells to cisplatin via p53 pathway

    Get PDF
    Purpose: To uncover the functional effect of homologous domain-associated protein kinase 2 (HIPK2) on the viability of cisplatin (DDP)-resistant gastric cancer (GC) cells and elucidate the possible mechanism of action.Methods: The effect of DDP on GC viability and apoptotic rate was evaluated using MTT and flow cytometry (FCM) assays. The potential effect of HIPK2 on DDP sensitivity and cell apoptosis was investigated in the presence of cisplatin while the effect of HIPK2 on p53 activation was determined by immunoblot assay.Results: HIPK2 expression was decreased in DDP-resistant GC cell while upregulation of HIPK2 reduced growth, but promoted apoptosis in DDP-resistant GC cells. Further investigations showed that HIPK2 promoted p53 activation, while suppression of p53 weakened the inhibitory effect of HIPK2 on DDP-resistance in GC cells.Conclusion: The results suggest that HIPK2 is a promising and important therapeutic factor for the regulation of the resistance of GC cells to DDP. Thus, may have a role to play in the management of gastric cancer Keywords: Gastric cancer, Cisplatin, HIPK2, Homologous domain-associated protein kinase 2, p53 pathway, Therapeutic targe

    Semantic-Aware Fine-Grained Correspondence

    Full text link
    Establishing visual correspondence across images is a challenging and essential task. Recently, an influx of self-supervised methods have been proposed to better learn representations for visual correspondence. However, we find that these methods often fail to leverage semantic information and over-rely on the matching of low-level features. In contrast, human vision is capable of distinguishing between distinct objects as a pretext to tracking. Inspired by this paradigm, we propose to learn semantic-aware fine-grained correspondence. Firstly, we demonstrate that semantic correspondence is implicitly available through a rich set of image-level self-supervised methods. We further design a pixel-level self-supervised learning objective which specifically targets fine-grained correspondence. For downstream tasks, we fuse these two kinds of complementary correspondence representations together, demonstrating that they boost performance synergistically. Our method surpasses previous state-of-the-art self-supervised methods using convolutional networks on a variety of visual correspondence tasks, including video object segmentation, human pose tracking, and human part tracking.Comment: 26 page

    Assessment of causal associations between uric acid and 25-hydroxyvitamin D levels

    Get PDF
    BackgroundPrevious observational studies have revealed the association between serum uric acid and 25-hydroxyvitamin D. However, the causality and the direction of the associations remain unknown. Thus, we performed a two-sample bidirectional Mendelian Randomization (MR) analysis to investigate the causal association between uric acid and 25-hydroxyvitamin D and to determine the direction of the association.MethodBased on the summary-level GWAS data from large genome-wide association studies, several steps were taken in our analysis to select eligible single-nucleotide polymorphisms (SNPs), which were strongly related to exposure as the instrumental variables. We used different analytical methods, such as inverse-variance weighting (IVW) method, weighted median, MR-Egger regression, and weighted mode method, to make our result more robust and reliable. The IVW method was used as the primary analysis. The Cochranā€™s Q test, MR-Egger intercept test, MR-PRESSO method, and ā€œleave-one-outā€ sensitivity analysis was performed to evaluate the heterogeneities, horizontal pleiotropy, and robustness of the results. MR analyses were also conducted using genetic risk scores (GRS) as instrumental variables in both directions by using the same summary-level GWAS data.ResultsOur two-sample MR analysis suggested a causal association of genetically predicted uric acid on 25-hydroxyvitamin D [IVW method: Ī²(SE), āˆ’0.0352(0.0149); p = 0.0178], which suggested that a per mg/dl increase in uric acid was associated with a decrease of 0.74 nmol/L of 25-hydroxyvitamin D, and the above results remained stable in the sensitivity analysis. By contrast, four MR methods suggested no causal relationship of 25-hydroxyvitamin D on serum uric acid [IVW Ī²(SE), 0.0139 (0.0635); p = 0.826; MR-Egger Ī²(SE), 0.0671 (0.108); p = 0.537; weighted median Ī²(SE), 0.0933 (0.0495); p = 0.0598; weighted mode Ī²(SE), 0.0562 (0.0463); p = 0.228, respectively]. After excluding the SNPs, which were associated with confounding factors and outlier SNPs, the IVW method suggested that there was still no causal association of 25-hydroxyvitamin D on serum uric acid. The GRS approach showed similar results.ConclusionsSerum uric acid may causally affect the 25-hydroxyvitamin D levels, whereas the causal role of 25-hydroxyvitamin D on uric acid was not supported in our MR analysis. Our findings suggest that increased levels of uric acid should prompt investigation for vitamin D deficiency

    A Universal Semantic-Geometric Representation for Robotic Manipulation

    Full text link
    Robots rely heavily on sensors, especially RGB and depth cameras, to perceive and interact with the world. RGB cameras record 2D images with rich semantic information while missing precise spatial information. On the other side, depth cameras offer critical 3D geometry data but capture limited semantics. Therefore, integrating both modalities is crucial for learning representations for robotic perception and control. However, current research predominantly focuses on only one of these modalities, neglecting the benefits of incorporating both. To this end, we present Semantic-Geometric Representation (SGR), a universal perception module for robotics that leverages the rich semantic information of large-scale pre-trained 2D models and inherits the merits of 3D spatial reasoning. Our experiments demonstrate that SGR empowers the agent to successfully complete a diverse range of simulated and real-world robotic manipulation tasks, outperforming state-of-the-art methods significantly in both single-task and multi-task settings. Furthermore, SGR possesses the unique capability to generalize to novel semantic attributes, setting it apart from the other methods

    PročiŔćavanje i karakterizacija fibrinolitičkog enzima iz plijesni Rhizopus microsporus var. tuberosus

    Get PDF
    Extracellular fibrinolytic enzyme from Rhizopus microsporus var. tuberosus was purified and characterised. The microorganism was isolated in a distillery from daqu, a fermentative agent used in the production of Chinese liquor and vinegar at diff erent temperatures. The fibrinolytic enzyme was partially purifi ed by ammonium sulphate precipitation, dialysis, DEAE SepharoseĀ® Fast Flow ion exchange chromatography and Sephadex G-75 gel filtration chromatography. The molecular mass of the fi brinolytic enzyme was estimated to be 24.5 kDa by SDS-PAGE. The purified enzyme showed optimal activity at pH=7.0 and 37 Ā°C by fibrin plate method. It showed stronger resistance to the inhibition by trypsin and was stable at 37 Ā°C retaining 96.1 % residual activity aft er 4 h of incubation. The fibrinolytic activity of the enzyme was enhanced by Na+, Ca2+, Mg2+ and Mn2+. Conversely, Zn2+ and Cu2+ partly inhibited enzymatic activity. Using fibrin plate method, we found that the enzyme not only degrades fibrin directly, but also activates plasminogen into plasmin to degrade fibrin. The results indicate that the pure enzyme has a potential in dissolving blood clot, and the possibility for application in the treatment of thrombosis.U radu je pročiŔćen i ispitan izvanstanični fibrinolitički enzim iz plijesni Rhizopus microsporus var. tuberosus. Mikroorganizam je izoliran u distileriji iz starter kulture koja se koristi za fermentaciju tradicionalnog kineskog likera i octa pri različitim temperaturama, tzv. daqu. Fibrinolitički je enzim djelomično pročiŔćen taloženjem pomoću amonijevog sulfata, dijalizom, ionskom kromatografijom na koloni DEAE Sepharose Fast Flow i gel-filtracijskom kromatografijom na koloni Sephadex G-7. Molekularna masa fibrinolitičkog enzima, određena pomoću SDS-PAGE, iznosila je 24,5 kDa. Optimalni uvjeti za aktivnost pročiŔćenog enzima bili su pH=7,0 i 37 Ā°C. Enzim je bio otporan na inhibiciju tripsinom, stabilan pri 37 Ā°C, te je zadržao 96,1 % aktivnosti nakon 4 sata inkubacije. Fibrinolitička se aktivnost enzima pojačala u prisutnosti iona Na+, Ca2+, Mg2+ i Mn2+, dok su ioni Zn2+ i Cu2+ djelomično inhibirali njegovu aktivnost. Utvrđeno je da enzim izravno razgrađuje fibrin, i aktivira plazminogen, pri čemu nastali plazmin razgrađuje fibrin. Rezultati pokazuju da se pročiŔćeni enzim može primijeniti u liječenju tromboze, jer ima sposobnost razgradnje krvnih ugruÅ”aka

    EGFR inhibitor C225 increases the radiosensitivity of human lung squamous cancer cells

    Get PDF
    Background: The purpose of the present study is to investigate the direct biological effects of the epidermal growth factor receptor (EGFR) inhibitor C225 on the radiosensitivity of human lung squamous cancer cell-H520. H520 cells were treated with different dosage of (60)Co gamma ray irradiation (1.953 Gy/min) in the presence or absence of C225. The cellular proliferation, colony forming capacity, apoptosis, the cell cycle distribution as well as caspase-3 were analyzed in vitro. Results: We found that C225 treatment significantly increased radiosensitivity of H-520 cells to irradiation, and led to cell cycle arrest in G(1) phase, whereas (60)Co gamma ray irradiation mainly caused G(2) phase arrest. H-520 cells thus displayed both the G(1) and G(2) phase arrest upon treatment with C225 in combination with (60)Co gamma ray irradiation. Moreover, C225 treatment significantly increased the apoptosis percentage of H-520 cells (13.91% +/- 1.88%) compared with the control group (5.75% +/- 0.64%, P < 0.05). Conclusion: In this regard, C225 treatment may make H-520 cells more sensitive to irradiation through the enhancement of caspase-3 mediated tumor cell apoptosis and cell cycle arrest.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000284001800001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701OncologySCI(E)PubMed2ARTICLE391

    Central Angiotensin II Stimulation Promotes Ī² Amyloid Production in Sprague Dawley Rats

    Get PDF
    BACKGROUND: Stress and various stress hormones, including catecholamines and glucocorticoids, have recently been implicated in the pathogenesis of Alzheimer's disease (AD), which represents the greatest unresolved medical challenge in neurology. Angiotensin receptor blockers have shown benefits in AD and prone-to-AD animals. However, the mechanisms responsible for their efficacy remain unknown, and no studies have directly addressed the role of central angiotensin II (Ang II), a fundamental stress hormone, in the pathogenesis of AD. The present study focused on the role of central Ang II in amyloidogenesis, the critical process in AD neuropathology, and aimed to provide direct evidence for the role of this stress hormone in the pathogenesis of AD. METHODOLOGY/PRINCIPAL FINDINGS: Increased central Ang II levels during stress response were modeled by intracerebroventricular (ICV) administration of graded doses of Ang II (6 ng/hr low dose, 60 ng/hr medium dose, and 600 ng/hr high dose, all delivered at a rate of 0.25 Āµl/hr) to male Sprague Dawley rats (280-310 g) via osmotic pumps. After 1 week of continuous Ang II infusion, the stimulation of Ang II type 1 receptors was accompanied by the modulation of amyloid precursor protein, Ī±-, Ī²-and Ī³-secretase, and increased Ī² amyloid production. These effects could be completely abolished by concomitant ICV infusion of losartan, indicating that central Ang II played a causative role in these alterations. CONCLUSIONS/SIGNIFICANCE: Central Ang II is essential to the stress response, and the results of this study suggest that increased central Ang II levels play an important role in amyloidogenesis during stress, and that central Ang II-directed stress prevention and treatment might represent a novel anti-AD strategy
    • ā€¦
    corecore