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A Low-Cost Flash Photographic System for Visualization of Droplets in Drop-on-Demand Inkjet
摘要： Hepatocellular carcinoma (HCC) is one of the most common and deadly human cancers. The 5-year survival rate is very low. Unfortunately, there are few efficacious therapeutic options. Until recently, Sorafenib has been the only available systemic drug for advanced HCC. However, it has very limited survival benefits, and new therapies are urgently needed. In this study, we investigated the anti-HCC activity of carfilzomib, a second-generation, irreversible proteasome inhibitor, as a single agent and in combination with sorafenib. In vitro, we found that carfilzomib has moderate anticancer activity toward liver cancer cells, but strongly enhances the ability of sorafenib to suppress HCC cell growth, proliferation, migration, invasion, and survival. Remarkably, the drug combination exhibits even more potent antitumor activity when tested in animal tumor models. Mechanistically, the combined treatment activates caspase-dependent and endoplasmic reticulum stress/CHOP-mediated apoptotic pathways, and suppresses epithelial–mesenchymal transition. In conclusion, our results demonstrate that the combination of carfilzomib and sorafenib has synergistic antitumor activities against HCC, providing a potential therapeutic strategy to improve the mortality and morbidity of HCC patients.
关键词： Hepatocellular Carcinoma,Proteasome Inhibitor,ER Stress,Apoptosis,Sorafenib,EMT,Carfilzomib,Synergistic Inhibition
更新于2025-09-23 15:23:52
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Black phosphorus nanosheets based sensitive protease detection and inhibitor screening
摘要： Proteases, as one of the most significant kind of digestive enzymes, are closely related to a variety of physiological processes and diseases. Herein, a black phosphorus nanosheets (BPs) based sensitive fluorometric method for protease detection and inhibitor screening is proposed. The aqueous solution of perylene probe (probe 1) displays a strong fluorescence. BPs, as novel discovered two-dimensional (2D) materials, can adsorb probe 1 through electrostatic interactions, which causes fluorescence quenching of probe 1. Histone can control the interactions between the perylene probe and BPs, which can be further regulated by the introduction of a protease. Thus, the protease activity can be monitored by detecting the fluorescence intensity changes of probe 1. The method is label free, sensitive and selective. As low as 1 ng/mL trypsin can be easily detected.
关键词： trypsin,inhibitor,protease,black phosphorus nanosheets,fluorescence,perylene probe
更新于2025-09-23 15:23:52
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A fluorometric method for determination of the activity of T4 polynucleotide kinase by using a DNA-templated silver nanocluster probe
摘要： The authors describe a turn-off fluorometric method for the determination of the activity of the T4 polynucleotide kinase (T4 PNK). It is based on the use of DNA-templated silver nanoclusters (AgNCs). DNA probes with terminal 5′ hydroxy groups are used as substrates for DNA phosphatases. If subsequently treated with T4 PNK and Lambda exonuclease (λ exo), the AgNC DNA probes with a modified C-rich sequence and the G-rich sequence is separated. Upon their separation, the strong fluorescence (with excitation/emission maxima at 580/650 nm) that is caused by the proximity of the G-rich region and the C-rich region in the AgNCs decreases sharply. This enabled the fluorometric kinetic determination of the activity of T4 PNK. The assay is characterized by a wide linear range (from 0.01 to 12.5 U·mL?1), a low detection limit (0.01 U·mL?1) and short assay time (typically 60 min). This makes it a promising tool for use in studying processes related to DNA phosphorylation, in drug discovery and in diagnostics.
关键词： DNA-AgNCs,Cell extracts,Clinical diagnostics,Lambda exonuclease,Proximity effect,T4 PNK,Inhibitor,ATP,Na2HPO4,Phosphorylation
更新于2025-09-23 15:23:52
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HMGB1 siRNA can reduce damage to retinal cells induced by high glucose in vitro and in vivo
摘要： Background: Diabetic retinopathy (DR), one of the most common complications of late-phase diabetes, is associated with many risk factors, among which continuous low-grade inflammation is one of the principal ones. As such, lowering inflammation levels and maintain the viability of human retinal endothelial cells (HRECs) are critical for DR therapy. HMGB1 is a well-known proinflammatory cytokine. However, whether HMGB1 small interfering RNA (siRNA) can protect retina cells under a high-glucose environment from morphological changes and functional abnormalities remain undetermined. We aimed to investigate the effect of HMGB1 siRNA on retinal cells in DR. Materials and methods: A total of 80 adult Wistar rats were randomly divided into four groups (n=20 each): normal control, diabetes mellitus (DM), scrambled (Scr) siRNA, and HMGB1 siRNA. Rats in the DM, Scr siRNA, and siRNA groups were established by intraperitoneal injection of streptozotocin. At 16 weeks after injection, rats in the siRNA and Scr-siRNA groups were intravitreally injected with 2 μL HMGB1 siRNA and 2 μL Scr-siRNA, while rats in the control and DM groups were intravitreally injected with the same dose of sterile saline. At 1 week after injections, we performed the following experiments. Immunohistochemical staining and real-time quantitative polymerase chain reaction were performed to test HMGB1 protein and messenger RNA expression in retinas. We performed TUNEL assays to detect retinal cell apoptosis and electroretinography to detect retinal function. In HRECs treated with high glucose, proliferation, morphology, apoptosis, superoxide dismutase (SOD), and reactive oxygen species production were detected. Western blot was applied to determine the expressions of HMGB1 and its related protein and apoptosis protein. Results: Intravitreal injection of HMGB1 siRNA reduced protein and messenger RNA expression of HMGB1 (both P,0.05). Intravitreal injection of HMGB1 siRNA reduced apoptosis of retinal cells (P,0.05), protected morphological changes in the retina, and improved the function of the retina (P,0.05). In HRECs treated with high glucose, HMGB1 siRNA pretreatment increased cell viability, reduced cell apoptosis, and reduced oxidative damage to cells (all P,0.05). Western blot detection found that HMGB1 siRNA pretreatment can inhibit the expression of cleaved caspase 3 and improve the expression of BCL2 (P,0.05). HMGB1 and NFκB expression increased in a time-dependent manner in the high-glucose environment and IKKβ and NFκB protein expression decreased significantly after HMGB1 silencing. Conclusion: As a therapeutic target, HMGB1 siRNA can reduce retinal cell damage induced by high glucose in vitro and in vivo and delay DR progress through the HMGB1–IKKβ–NFκB signaling pathway.
关键词： small interfering RNA,diabetic retinopathy,human retinal endothelial cells,inhibitor of nuclear factor κB,nuclear factor κB,high-mobility group box 1
更新于2025-09-23 15:22:29
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Identification of Potent Caspase-8 Inhibitors from a Library of Fluorescent Natural Products Screened by an AIEgen-based Light-up Probe
摘要： Fluorescent natural products are a rich source of drugs and chemical probes. But their inborn fluorescence may interfere with the fluorescence-based screening assays. Caspase-8 is a key player in apoptosis. Inhibition of caspase-8 found to be beneficial for inflammatory and neurodegenerative diseases. But its small molecular inhibitors remain sparsely reported. In this study, we firstly developed a caspase-8 targeting light-up probe based on an AIEgen. This fluorescent dye has a Stokes shift of 200 nm which could avoid the inborn fluorescence signal of natural products. When screening a library of 86 fluorescent natural products, we found for the first time Gossypol showed potent inhibition towards caspase-8 in vitro and in situ. This unique kind of light-up probe coupled with colored natural products could be an efficient way in the hit discovery for druggable targets.
关键词： natural product,aggregation-induced emission,inhibitor screening,caspase-8,fluorescence
更新于2025-09-23 15:22:29
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Ultrasensitive detection of protein kinase activity based on the Au NPs mediated electrochemiluminescence amplification of S2O82?–O2 system
摘要： An electrochemiluminescence (ECL) biosensor based on Au NPs enhanced ECL signal of S2O8 2?–O2 system has been constructed for ultrasensitive detection of protein kinase activity. In the presence of ATP-s and protein kinase A (PKA), Au NPs can be captured on the thoil-phosphorylated peptides modified electrode surface, generating an enhanced ECL emission of S2O8 2?–O2 system. With increasing the PKA activity, more Au NPs can be captured on the modified electrode surface, resulting in the gradually enhanced ECL intensity of S2O8 2?–O2 system. Based on the Au NPs mediated the ECL amplification of S2O8 2?–O2 system, the activity of PKA can be detected sensitively with a limit of detection of 0.0002 U/mL, which is much lower than the most sensitive method in previous reports. The good conductivity and high catalytic ability of the Au NPs are revealed to account for the enhanced sensitivity in this ECL biosensor. The ECL biosensor has been successfully used for monitoring PKA activity in biological samples and screening of protein kinase inhibition.
关键词： Protein kinase A,Electrochemiluminescence biosensor,S2O8 2?–O2 system,Inhibitor,Enhancement effect
更新于2025-09-23 15:22:29
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Development of Dissolution Inhibitor in Chemically Amplified Positive Tone Thick Film Resist
摘要： Thick film resist is applied to a template for microelectrode used in semiconductor device integration. Utilization of positive type resist in chemically amplified system for thick film is expected to improve production efficiency of semiconductor device integration, but improvement of resolution is required. In order to improve the resolution of chemically amplified positive tone thick film resist, chemical structure of the dissolution inhibitor (DI) was designed for the control of solubility in resist polymer. The increase of molecular size in DI improved the dissolution inhibiting ability for the resist polymer in the unexposed area and the high acidity of the deprotected DI having carboxyl group improved dissolution promoting ability for the resist polymer in the exposed area. The resist containing DI possessing a large molecular size and high acidity improved its sensitivity and resolution.
关键词： Positive tone resist,Chemically amplified system,Thick film resist,Dissolution inhibitor
更新于2025-09-23 15:21:21
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Topical administration of a ROCK inhibitor prevents anterior subcapsular cataract induced by UV-B irradiation
摘要： The deposition of extracellular matrix (ECM)—which is mainly composed of type I collagen—in anterior subcapsular cataracts (ASCs) during epithelial-to-mesenchymal transition (EMT) of lens epithelial cells (LECs) decreases visual function. Transforming growth factor (TGF)-β is a key factor in the induction of EMT in LECs. Although Rho kinase (ROCK) plays an important role in EMT induced by TGF-β, it is unknown whether ROCK inhibition affects type I collagen expression in TGF-β-stimulated LECs and ASC formation. This was investigated in the present study both in vitro using human lens epithelium (HLE)-B3 cells and in vivo using mice with ultraviolet radiation (UVR)-B-induced cataracts. We found that TGF-β2 increased type I collagen mRNA expression in HLE-B3 cells; this was inhibited in a dose-dependent manner by treatment with the ROCK inhibitor Y-27632. UVR-B exposure caused ASC formation in mice. A histopathological examination revealed that LECs in the anterior subcapsular area were flattened and multi-layered, and had a spindle shape in cross section. Immunohistochemical analysis revealed the presence of α-smooth muscle actin and type I collagen around these flattened LECs; these opacities were reduced by topical instillation of Y-27632. These findings suggest that suppression of TGF-β signaling in LECs by topical application of a ROCK inhibitor can prevent the formation of ASCs.
关键词： lens epithelial cell,ROCK inhibitor,type I collagen,transforming growth factor-β,epithelial-to-mesenchymal transition
更新于2025-09-19 17:15:36
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Inhibitor of growth 4 affects hypoxia-induced migration and angiogenesis regulation in retinal pigment epithelial cells
摘要： Inhibitor of growth 4 (ING4), a potential tumor suppressor, is implicated in cell migration and angiogenesis. However, its effects on diabetic retinopathy (DR) have not been elucidated. In this study, we aimed to evaluate ING4 expression in normal and diabetic rats and clarify its effects on hypoxia‐induced dysfunction in human retinal pigment epithelial (ARPE‐19) cells. A Type 1 diabetic model was generated by injecting rats intraperitoneally with streptozotocin and then killed them 4, 8, or 12 weeks later. ING4 expression in retinal tissue was detected using western blot analysis, reverse transcription quantitative real‐time polymerase chain reaction (RT‐qPCR), and immunohistochemistry assays. After transfection with an ING4 overexpression lentiviral vector or small interfering RNA (siRNA), ARPE‐19 migration under hypoxia was tested using wound healing and transwell assays. The angiogenic effect of conditioned medium (CM) from ARPE‐19 cells was examined by assessing human retinal endothelial cell (HREC) capillary tube formation. Additionally, western blot analysis and RT‐qPCR were performed to investigate the signaling pathways in which ING4, specificity protein 1 (Sp1), matrix metalloproteinase 2 (MMP‐2), MMP‐9, and vascular endothelial growth factor A (VEGF‐A) were involved. Here, we found that ING4 expression was significantly reduced in the diabetic rats’ retinal tissue. Silencing ING4 aggravated hypoxia‐induced ARPE‐19 cell migration. CM collected from ING4 siRNA‐transfected ARPE‐19 cells under hypoxia promoted HREC angiogenesis. These effects were reversed by ING4 overexpression. Furthermore, ING4 suppressed MMP‐2, MMP‐9, and VEGF‐A expression in an Sp1‐dependent manner in hypoxia‐conditioned ARPE‐19 cells. Overall, our results provide valuable mechanistic insights into the protective effects of ING4 on hypoxia‐induced migration and angiogenesis regulation in ARPE‐19 cells. Restoring ING4 may be a novel strategy for treating DR.
关键词： migration,angiogenesis,diabetic retinopathy,retinal pigment epithelium cells,hypoxia,inhibitor of growth 4
更新于2025-09-19 17:15:36
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A Conformational Switch-based Fluorescent Biosensor for Homogeneous Detection of Telomerase Activity
摘要： As a universal tumor biomarker, research on the activity and inhibition of telomerase is of great importance for cancer diagnosis and therapy. Herein, we demonstrate the conformational switch-based fluorescence detection of telomerase activity using a redesigned RNA aptamer Spinach. Briefly, the original Spinach aptamer was extended at its 5’ end and folded into an inactive conformation, where association with the small molecule fluorophore, 5-difluoro-4-hydroxybenzylidene imidazolinone (DFHBI) was prevented. Only in the presence of telomerase, (TTAGGG)n repeats were added to the 3’ end of the telomerase substrate primer, and the elongation products hybridized with inactive Spinach molecules, triggering its conformational switch and refolding it into the active, DFHBI-binding conformation. Moreover, the fluorescence signal was further amplified through a target recycling circuit, where Ribonuclease H (RNase H) specifically hydrolyzed the phosphodiester bonds of RNA in the DNA-RNA hybrid. The released telomere products could then hybridize to new inactive Spinach molecules and initiate multiple amplification cycles. The proposed fluorescent biosensor presented great performance for telomerase activity detection from 100 to 5 × 104 Hela cells with a detection limit of 100 cells. Besides, this new assay offers a good biosensing platform for differentiation of cancer cell lines from normal cell line and evaluation the inhibition efficiency of telomere-binding ligand, which is of great importance for telomerase-related cancer diagnosis and therapy.
关键词： Telomerase activity,Spinach,Ribonuclease H,Inhibitor,Fluorescent biosensors
更新于2025-09-19 17:15:36