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Development of rhodamine-based fluorescent probes for sensitive detection of Fe <sup>3+</sup> in water: spectroscopic and computational investigations
摘要： The aim of this study was to investigate the expression of hypoxia-inducible factor-1α (HIF-1α) in keloids and its correlation with inflammatory responses and apoptosis. The keloid specimens resected in our hospital from November 2015 to February 2017 were selected as the pathological group, and the normal skin tissues from our hospital during the same period were selected as the control group. The expression of HIF-1α, inflammatory response cytokines, and apoptotic molecules in the tissues of two groups were detected. The messenger RNA (mRNA) expression of HIF-1α in the keloids in the pathological group was significantly higher than that in the control group, and the mRNA expression of interleukin (IL)-1β, IL-2, IL-6, and tumor necrosis factor (TNF)-α in the pathological group was significantly higher than those in the control group. The mRNA expression of Bax in the pathological group was significantly higher than that in the control group. The mRNA expression of Bcl-2, livin, and hPEBP4 in the pathological group was significantly lower than that in the control group. Pearson test showed that there was a positive correlation between the mRNA expression of HIF-1α and inflammatory cytokines including IL-1β, IL-2, IL-6, and TNF-α. There were also a positive correlation between the mRNA expression of HIF-1α and Bax and a negative correlation between the mRNA expression of HIF-1α and Bcl-2, livin, and hPEBP4. In conclusion, HIF-1α was highly expressed in keloids and closely related to inflammatory response cytokines and apoptosis molecules. Increased expression of HIF-1α in keloids may be an important factor in inflammatory responses and increased apoptosis in skin tissues.
关键词： inflammatory responses,hypoxia-inducible factor-1α,apoptosis,keloids
更新于2025-09-19 17:15:36
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All-trans retinoic acid stimulates the secretion of TGF-β2 via the phospholipase C but not the adenylyl cyclase signaling pathway in retinal pigment epithelium cells
摘要： Background: By investigating that (i) all-trans retinoic acid (ATRA) affects human retinal pigment epithelium (RPE) in expressing and secreting transforming growth factor (TGF)-β2 and (ii) U73122 (phospholipase C inhibitor) and SQ22536 (adenylyl cyclase inhibitor) regulate the ATRA-induced secretion of TGF-β2 in human RPE, we sought to interpret the signaling pathway of ATRA in promoting the development of myopia. Methods: The RPE cell line (D407) was treated with (i) ATRA (10 μM), (ii) U73122 (5–40 μM) and ATRA (10 μM), or (iii) SQ22536 (5–40 μM) and ATRA (10 μM). The control group was no-treated. After stimulated at 2, 4, 8, 16, 24, and 48 h, The expression and secretion of TGF-β2 was detected. Results: TGF-β2 in the cytoplasm was time-dependent increased by ATRA (p < 0.001). A time-dependent increase in the TGF-β2 protein of the supernatant was induced by ATRA (p < 0.001). U73122 (in the range of 5 to 40 μM) could suppress the secretion of TGF-β2 induced by ATRA (p < 0.001), and 40 μM U73122 could completely inhibit the up-regulated effect of 10 μM ATRA. However, SQ22536 (in the range of 5 to 40 μM) had no impact on the secretion of TGF-β2 induced by ATRA (p > 0.05). Conclusions: In RPE cells, ATRA stimulates the secretion of TGF-β2 via the phospholipase C signaling pathway but not the adenylyl cyclase signaling pathway. U73122 may inhibit the promotion of ATRA in the development of myopia.
关键词： Retinal pigment epithelium cells,All-trans retinoic acid,SQ22536,Transforming growth factor-β2,U73122
更新于2025-09-19 17:15:36
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Real-time molecular optical micro-imaging of EGFR mutations using a fluorescent erlotinib based tracer
摘要： Background: EGFR mutations are routinely explored in lung adenocarcinoma by sequencing tumoral DNA. The aim of this study was to evaluate a fluorescent-labelled erlotinib based theranostic agent for the molecular imaging of mutated EGFR tumours in vitro and ex vivo using a mice xenograft model and fibred confocal fluorescence microscopy (FCFM). Methods: The fluorescent tracer was synthesized in our laboratory by addition of fluorescein to an erlotinib molecule. Three human adenocarcinoma cell lines with mutated EGFR (HCC827, H1975 and H1650) and one with wild-type EGFR (A549) were xenografted on 35 Nude mice. MTT viability assay was performed after exposure to our tracer. In vitro imaging was performed at 1 μM tracer solution, and ex vivo imaging was performed on fresh tumours excised from mice and exposed to a 1 μM tracer solution in PBS for 1 h. Real-time molecular imaging was performed using FCFM and median fluorescence intensity (MFI) was recorded for each experiment. Results: MTT viability assay confirmed that addition of fluorescein to erlotinib did not suppress the cytotoxic of erlotinib on tumoral cells. In vitro FCFM imaging showed that our tracer was able to distinguish cell lines with mutated EGFR from those lines with wild-type EGFR (p < 0.001). Ex vivo FCFM imaging of xenografts with mutated EGFR had a significantly higher MFI than wild-type (p < 0.001). At a cut-off value of 354 Arbitrary Units, MFI of our tracer had a sensitivity of 100% and a specificity of 96.3% for identifying mutated EGFR tumours. Conclusion: Real time molecular imaging using fluorescent erlotinib is able to identify ex vivo tumours with EGFR mutations.
关键词： Lung cancer,Erlotinib,Theranostic,EGFR,Epidermal growth factor,Fibred confocal fluorescence microscopy,Molecular imaging
更新于2025-09-19 17:15:36
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Foreground Detection with Deeply Learned Multi-Scale Spatial-Temporal Features
摘要： The clinical efficacy and mechanism of Pralatrexate (PTX) combined with Palbociclib Isethionate (PAL) in the treatment of bladder cancer patients was investigated. A retrospective analysis of medical records of 82 bladder cancer patients admitted to Shengjing Hospital of China Medical University from February 2015 to February 2018 was performed. Patients treated with PTX combined with PAL served as study group (42 cases) and patients with conventional GC (gemcitabine plus cisplatin) chemotherapy regimen were the control group (40 cases). Changes in liver function indexes before and after treatment were observed, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total bilirubin (TBil). RT-qPCR was used for detection of relative expression levels of serum dihydrofolate reductase (DHFR) and vascular endothelial growth factor (VEGF) before and after treatment in the two groups. The clinical efficacy after treatment and adverse reactions during treatment were observed in the two groups. There was no significant difference in the clinical remission rate (RR) nor in the serum ALT, AST, ALP and TBil levels between the study and the control groups (P>0.05). Concentrations of serum ALT, AST, ALP and TBil were significantly higher than those before treatment in both groups (P<0.05). Serum ALT, AST, ALP and TBil concentrations in study group were significantly lower than those in control group (P<0.05). There was no significant difference in the incidence of thrombocytopenia and leukopenia between the two groups (P>0.05). There was no significant difference in relative expression levels of serum DHFR mRNA and VEGF mRNA before treatment between the study and control groups (P>0.05). Those after treatment were significantly lower than those before treatment in both groups (P<0.05), and those after treatment in study group were significantly lower than those in control group (P<0.05). PTX combined with PAL can reduce adverse reactions of nausea and vomiting and liver function impairment during treatment and suppress tumor neovascularization. This is achieved possibly by inhibiting expression levels of DHFR and VEGF, thereby killing cancer cells. PTX combined with PAL may become a new method for the treatment of bladder cancer patients. DHFR and VEGF are expected to become novel therapeutic targets for the treatment of bladder cancer.
关键词： combination therapy,vascular endothelial growth factor,dihydrofolate reductase,bladder cancer,Pralatrex,Palbociclib Isethionate
更新于2025-09-19 17:15:36
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New tolerance factor to predict the stability of perovskite oxides and halides
摘要： Predicting the stability of the perovskite structure remains a long-standing challenge for the discovery of new functional materials for many applications including photovoltaics and electrocatalysts. We developed an accurate, physically interpretable, and one-dimensional tolerance factor, τ, that correctly predicts 92% of compounds as perovskite or nonperovskite for an experimental dataset of 576 ABX3 materials (X = O2?, F?, Cl?, Br?, I?) using a novel data analytics approach based on SISSO (sure independence screening and sparsifying operator). τ is shown to generalize outside the training set for 1034 experimentally realized single and double perovskites (91% accuracy) and is applied to identify 23,314 new double perovskites (A2BB′X6) ranked by their probability of being stable as perovskite. This work guides experimentalists and theorists toward which perovskites are most likely to be successfully synthesized and demonstrates an approach to descriptor identification that can be extended to arbitrary applications beyond perovskite stability predictions.
关键词： data analytics,materials discovery,perovskite stability,tolerance factor,SISSO
更新于2025-09-19 17:15:36
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Giant, Voltage Tuned, Q-factors of Single Wall Carbon Nanotubes and Graphene at Room Temperature
摘要： Mastering dissipation in graphene based nanostructures is still the major challenge in most fundamental and technological exploitations of these ultimate mechanical nanoresonators. Although high quality factors have been measured for carbon nanotubes (> 106) and graphene (> 105) at cryogenic temperatures, room temperature values are orders of magnitude lower ((cid:39) 102). We present here a controlled quality factor increase of up to ×103 for these basic carbon nanostructures when externally stressed like a guitar string. Quantitative agreement is found with theory attributing this decrease in dissipation to the decrease in viscoelastic losses inside the material, an effect enhanced by tunable "soft clamping". Quality factors exceeding 25,000 for SWCNTs and 5000 for graphene were obtained on several samples, reaching the limits of the graphene material itself. The combination of ultra-low size and mass with high quality factors opens new perspectives for atomically localized force sensing and quantum computing as the coherence time exceeds state of the art cryogenic devices.
关键词： Q factor,graphene,carbon nanotube,NEMS,nanomechanics
更新于2025-09-19 17:15:36
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Method of correcting stitching errors in reconstructing a synthetic-aperture digital hologram with seams
摘要： We propose a correction method based on the shift theorem of the Fourier transform for the non-integer pixel stitching error in a synthetic-aperture digital hologram with seams. After being Fourier transformed, the sub-holograms stemming from the dislocated recording planes are multiplied by a phase factor and then superposed onto in-place sub-holograms. Finally, the entire hologram is inverse Fourier transformed for reconstruction. This method is applied to simulated particle detection. The results show that the correlation coefficient (CC) between the reconstructed image and the simulated target image is 1.5 times, by comparison with an image that does not involve the phase-factor correction, and particles at the seams are clearly visible. In addition, the effect of noise on the method is small. These verify the feasibility of the method.
关键词： phase factor,shift theorem of the Fourier transform,synthetic-apertures,Stitching errors,non-integer pixel
更新于2025-09-19 17:15:36
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Uniform Chiral Gap Synthesis for High Dissymmetry Factor in Single Plasmonic Gold Nanoparticle
摘要： Synthesis of chiral plasmonic material has been highlighted for the last decades with its optical properties and versatile potential applications. Recently reported aqueous based amino- acid-and peptide-directed synthesis of chiral plasmonic gold nanoparticles with 432 point-group symmetry shows exceptionally high chiroptic response within 100 nm scales. Despite its already excellent chiroptic response, single nanoparticle dark field scattering study revealed that full chiroptic potential of chiral gold nanoparticle is limited with its overall synthetic uniformity. Based on this knowledge, we present a multi-chirality-evolution step synthesis method for the enhancement of chiroptic response through increase in particle uniformity. Detailed time variant study and interrelationship study of reaction parameters allowed the systematic construction of design principles for chiral nanoparticle with exceptional chiroptic response. With the application of precisely controlled growth kinetic to two distinct growth regimes, modified chiral gold nanoparticle showed significantly improved uniformity, achieving improved dis-symmetry factor of g = 0.31. We expect that our strategy will aid in precise morphology and property control for chiral nanomaterials which to be used in various plasmonic metamaterial applications.
关键词： chiral nanoparticle,chirality,seed-mediated method,plasmonic nanoparticle,dissymmetric factor
更新于2025-09-19 17:13:59
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Ultrahigh Q-factor dual-band terahertz perfect absorber with dielectric grating slit waveguide for sensing
摘要： Terahertz (THz) perfect absorber with ultra-narrow bandwidth at near-unity absorbance has been a challenging issue due to mutual restriction of elemental requirements in design. Here, we propose an extremely sharp dual-band THz perfect absorber with ultrahigh Q-factor and near-unity absorbance by incorporating a Fabry-Perot micro-cavity into dielectric grating slit waveguide. Full-wave simulation demonstrates that the proposed structure not only achieves ultra-narrow band perfect absorption with an ultrahigh Q-factor of 4600 in THz regime, but also shows extraordinary sensing performance with a record figure of merit (FOM) of 2415 at THz frequencies. The optimized guided mode resonance leads to the ultrahigh Q-factor through suppressing the absorption and radiation losses. The enhanced interaction between the cavity localized fields and the analytes significantly improves THz sensing capability. Our design approach shows a promising future in simple and inexpensive THz biochemical sensors.
关键词： THz sensing,Terahertz wave,perfect absorber,ultrahigh Q-factor
更新于2025-09-19 17:13:59
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High performance nBn detectors based on InGaAsSb bulk materials for short wavelength infrared detection
摘要： Objective: To investigate whether hydrogen sulfide (H2S) counteracts formaldehyde (FA)-induced cognitive defects and whether the underlying mechanism is involved in the upregulation of hippocampal brain-derived neurotrophic factor (BDNF) expression. Methods: The cognitive function of rats was evaluated by the Morris water maze (MWM) test and the novel object recognition test. The content of superoxide dismutase (SOD) and malondialdehyde (MDA) in the hippocampus were detected by enzyme-linked immunosorbent assay (ELISA). The neuronal apoptosis in the hippocampal CA1 region was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end (TUNEL) staining. The expression of the BDNF protein was detected by Western blot and immunohistochemistry. Results: We found that sodium hydrosulfide (NaHS, a donor of H2S) significantly reversed the impairment in the function of learning and memory in the MWM test and the novel objective recognition task induced by intracerebroventricular injection of FA. We also showed that NaHS significantly reduced the level of MDA, elevated the level of SOD, and decreased the amount of TUNEL-positive neurons in the hippocampus of FA-exposed rats. Moreover, NaHS markedly increased the expression of hippocampal BDNF in FA-exposed rats. Conclusions: H2S attenuates FA-induced dysfunction of cognition and the underlying mechanism is involved in the reduction of hippocampal oxidative damage and apoptosis as well as upregulation of hippocampal BDNF.
关键词： Cognitive defect,Oxidative stress,Brain-derived neurotrophic factor,Formaldehyde,Hydrogen sulfide,Apoptosis
更新于2025-09-19 17:13:59