ABSTRACT
Fly ash-slag-based alkali-activated materials have excellent mechanical performance and a low carbon footprint, and they have emerged as a promising alternative to Portland cement. Therefore, replacing traditional Portland cement with slag-desulfurization gypsum-based alkali-activated materials will help to make better use of the waste, protect the environment, and improve the materials' performance. In order to better understand it and thus better use it in engineering, it needs to be characterized for performance and compositional design. This study developed a novel framework for performance characterization and composition design by combining Categorical Gradient Boosting (CatBoost), simplicial homology global optimization (SHGO), and laboratory tests. The CatBoost characterization model was evaluated and discussed based on SHapley Additive exPlanations (SHAPs) and a partial dependence plot (PDP). Through the proposed framework, the optimal composition of the slag-desulfurization gypsum-based alkali-activated materials with the maximum flexural strength and compressive strength at 1, 3, and 7 days is Ca(OH)2: 3.1%, fly ash: 2.6%, DG: 0.53%, alkali: 4.3%, modulus: 1.18, and W/G: 0.49. Compared with the material composition obtained from the traditional experiment, the actual flexural strength and compressive strength at 1, 3, and 7 days increased by 26.67%, 6.45%, 9.64%, 41.89%, 9.77%, and 7.18%, respectively. In addition, the results of the optimal composition obtained by laboratory tests are very close to the predictions of the developed framework, which shows that CatBoost characterizes the performance well based on test data. The developed framework provides a reasonable, scientific, and helpful way to characterize the performance and determine the optimal composition for civil materials.
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Nitroreductase (NTR) overexpression often occurs in tumors, highlighting the significance of effective NTR detection. Despite the utilization of various optical methods for this purpose, the absence of an efficient tumor-targeting optical probe for NTR detection remains a challenge. In this research, a novel tumor-targeting probe (Cy-Bio-NO2) is developed to perform dual-modal NTR detection using near-infrared fluorescence and photoacoustic techniques. This probe exhibits exceptional sensitivity and selectivity to NTR. Upon the reaction with NTR, Cy-Bio-NO2 demonstrates a distinct fluorescence "off-on" response at 800 nm, with an impressive detection limit of 12 ng/mL. Furthermore, the probe shows on-off photoacoustic signal with NTR. Cy-Bio-NO2 has been successfully employed for dual-modal NTR detection in living cells, specifically targeting biotin receptor-positive cancer cells for imaging purposes. Notably, this probe effectively detects tumor hypoxia through dual-modal imaging in tumor-bearing mice. The strategy of biotin incorporation markedly enhances the probe's tumor-targeting capability, facilitating its engagement in dual-modal imaging at tumor sites. This imaging capacity holds substantial promise as an accurate tool for cancer diagnosis.
Subject(s)
Fluorescent Dyes , Nitroreductases , Optical Imaging , Animals , Humans , Mice , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Mice, Inbred BALB C , Mice, Nude , Molecular Structure , Neoplasms/diagnostic imaging , Neoplasms, Experimental/diagnostic imaging , Neoplasms, Experimental/metabolism , Nitroreductases/metabolism , Nitroreductases/analysis , Photoacoustic Techniques , Nitrogen Dioxide/chemical synthesis , Nitrogen Dioxide/chemistryABSTRACT
OBJECTIVE: The purpose of this study was to investigate the ability of radiomic characteristics of magnetic resonance images to predict vascular endothelial growth factor (VEGF) expression in hepatocellular carcinoma (HCC) patients. METHODS: One hundred and twenty-four patients with HCC who underwent fat-suppressed T2-weighted imaging (FS-T2WI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) one week before surgical resection were enrolled in this retrospective study. Immunohistochemical analysis was used to evaluate the expression level of VEGF. Radiomic features were extracted from the axial FS-T2WI, DCE-MRI (arterial phase and portal venous phase) images of axial MRI. Least absolute shrinkage and selection operator (LASSO) and stepwise regression analyses were performed to select the best radiomic features. Multivariate logistic regression models were constructed and validated using tenfold cross-validation. Receiver operating characteristic (ROC) curve analysis, calibration curve analysis and decision curve analysis (DCA) were employed to evaluate these models. RESULTS: Our results show that there were 94 patients with high VEGF expression and 30 patients with low VEGF expression among the 124 HCC patients. The FS-T2WI, DCE-MRI and combined MRI radiomics models had AUCs of 0.8713, 0.7819, and 0.9191, respectively. There was no significant difference in the AUC between the FS-T2WI radiomics model and the DCE-MRI radiomics model (p > 0.05), but the AUC for the combined model was significantly greater than the AUCs for the other two models (p < 0.05) according to the DeLong test. The combined model had the greatest net benefit according to the DCA results. CONCLUSION: The radiomic model based on multisequence MR images has the potential to predict VEGF expression in HCC patients. The combined model showed the best performance.
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Objective: Sphingosine-1-phosphate receptor (S1PR) modulators have recently attracted increasing attention for the treatment of multiple sclerosis (MS). Despite their preference in the clinic, multiple adverse events (AEs) continue to be reported every year. This study aimed to investigate the potential AEs as well as related important medical events (IMEs) signal associated with S1PR modulators, including fingolimod, siponimod and ozanimod in a real-world study using the FDA Adverse Event Reporting System (FAERS) database. Methods: All data were collected from the FAERS database, spanning from the fourth quarter of 2010(2010Q4) to the second quarter of 2023 (2023Q2). Potential AE and IME signals of S1PR modulators were identified based on a disproportionality analysis using the reporting odds ratio (ROR), proportional reporting ratio (PRR), and the bayesian confidence propagation neural network of information components (IC). Results: Overall, 276,436 reports of fingolimod, 20,972 reports of siponimod and 10,742 reports of ozanimod were analyzed from the FAERS database. Among reports, females were more prone to develop AEs (73.71% for females vs. 23.21% for males), and more than 50% of patients suffered from AEs were between 18 and 64 years. Subsequently, we investigated the top 20 AEs associated with the signal strength of S1PR modulators at the preferred term (PT) level, and identified 31 (8 vs. 11 vs. 12, respectively) unlabeled risk signals such as thrombosis, uterine disorder and reproductive system and breast disorders. Furthermore, we discovered that the S1PR modulator reported variations in the possible IMEs, and that the IMEs associated with ocular events were reported frequently. It's interesting to note that infection and malignancy are prominent signals with both fingolimod and siponimod in the top 20 PTs related to mortality reports. Conclusion: The present investigation highlights the possible safety risks associated with S1PR modulators. The majority of AEs are generally consistent with previous studies and are mentioned in the prescribing instructions, however, several unexpected AE signals have also been observed. Ozanimod showed the lowest signal intensity and a better safety profile than the other S1PR modulators. Due to the short marketing time of drugs and the limitations of spontaneous reporting database, further research is required to identify potential AEs related to S1PR modulators.
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Fatty liver disease affects at least 25 percent of the population worldwide and is a severe metabolic syndrome. Viscosity is closely related to fatty liver disease, so it is urgent to develop an effective tool for monitoring viscosity. Herein, a NIR fluorescent probe called MBC-V is developed for imaging viscosity, consisting of dimethylaniline and malonitrile-benzopyran. MBC-V is non-fluorescent in low viscosity solutions due to intramolecular rotation. In high viscosity solution, the intramolecular rotation of MBC-V is suppressed and the fluorescence is triggered. MBC-V has long emission wavelength at 720 nm and large Stokes shift about 160 nm. Moreover, MBC-V can detect changes in cell viscosity in fatty liver cells, and can image the therapeutic effects of drug in fatty liver cells. By taking advantage of NIR emission, MBC-V can be used as an imaging tool for fatty liver disease and a way to evaluate the therapeutic effect of drug for fatty liver disease.
Subject(s)
Aniline Compounds , Fatty Liver , Fluorescent Dyes , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Animals , Viscosity , Mice , Fatty Liver/diagnostic imaging , Fatty Liver/drug therapy , Aniline Compounds/chemistry , Optical Imaging , Humans , Benzopyrans/chemistry , Benzopyrans/chemical synthesis , Nitriles/chemistryABSTRACT
PURPOSE: This study is to evaluate the correlation between retrobulbar perfusion deficits and glaucomatous visual field defects. METHODS: Eighty-four patients with glaucoma and 17 normal subjects serving as controls were selected. Color Doppler imaging (CDI) was used to measure the changes in blood flow parameters in the retrobulbar ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (SPCAs). Visual field testing was performed using a Humphrey perimeter, categorizing the visual field deficits into four stages according to the Advanced Glaucoma Intervention Study (AGIS) scoring method. Subsequently, the correlation of retrobulbar hemodynamic parameter alterations among glaucomatous patients with varying visual field defects was examined. RESULTS: The higher the visual field stage, the lower the peak systolic velocity (PSV) of the OA, CRA, and SPCAs in glaucomatous patients. The CRA had the highest sensitivity to changes in its PSV. The PSV of the temporal SPCA (TSPCA-PSV) was lower in advanced glaucoma than in early-stage glaucoma. The PSVs of the OA, CRA, and TSPCA, as well as the resistance index of the CRA (CRA-RI), were positively correlated with the visual field index and the mean deviation. Except for that of OA, the PSV of the retrobulbar vessels was negatively correlated with the pattern standard deviation (PSD). The OA-PSV and end-diastolic velocity (EDV) of the CRA and TSPCA were lower in patients with superior visual field defects than in those with inferior visual field defects. CONCLUSIONS: Greater severity of visual field defects corresponded to poorer retrobulbar blood flow in glaucomatous patients. Patients suffered significant perfusion impairments in the CRA at the early stage, accompanied by SPCA perfusion disorder at the advanced stage. The presence of a bow-shaped defect in the superior or inferior region of the visual field in moderate-stage glaucoma was closely correlated with retrobulbar vascular EDV. TRIAL REGISTRATION: ChiCTR2200059048 (2022-04-23).
ABSTRACT
Elongin B (ELOB), a pivotal element in the ELOB/c-Cullin2/5-SOCS-box E3 ubiquitin-protein ligase complex, plays a significant role in catalyzing the ubiquitination and subsequent degradation of a broad spectrum of target proteins. Notably, it is documented to facilitate these processes. However, the regulatory role of ELOB in breast cancer remains ambiguous. In this study, through bio-informatic analysis of The Cancer Genome Atlas and Fudan University Shanghai Cancer Center database, we demonstrated that ELOB was over-expressed in breast cancer tissues and was related to unfavorable prognosis. Additionally, pathway enrichment analysis illustrated that high expression of ELOB was associated with multiple cancer promoting pathways, like cell cycle, DNA replication, proteasome and PI3K - Akt signaling pathway, indicating ELOB as a potential anticancer target. Then, we confirmed that both in vivo and in vitro, the proliferation of breast cancer cells could be significantly suppressed by the down-regulation of ELOB. Mechanically, immunoprecipitation and in vivo ubiquitination assays prompted that, as the core element of Cullin2-RBX1-ELOB E3 ligase (CRL2) complex, ELOB regulated the ubiquitination and the subsequent degradation of oncoprotein p14/ARF. Moreover, the anticancer efficacy of erasing ELOB could be rescued by simultaneous knockdown of p14/ARF. Finally, through analyzing breast cancer tissue microarrays and western blot of patient samples, we demonstrated that the expression of ELOB in tumor tissues was elevated in compared to adjacent normal tissues. In conclusion, ELOB is identified to be a promising innovative target for the drug development of breast cancer by promoting the ubiquitination and degradation of oncoprotein p14/ARF.
Subject(s)
Breast Neoplasms , Cell Proliferation , Elongin , Ubiquitination , Humans , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/genetics , Female , Elongin/metabolism , Elongin/genetics , Animals , Cell Line, Tumor , Cell Proliferation/genetics , Disease Progression , Mice, Nude , Mice , Gene Expression Regulation, Neoplastic , Signal Transduction , Mice, Inbred BALB C , MCF-7 Cells , Transcription Factors/metabolism , Transcription Factors/geneticsABSTRACT
Purpose: This study aimed to investigate the role of the long non-coding RNA (lncRNA) NEAT1 in corneal epithelial wound healing in mice. Methods: The central corneal epithelium of wild-type (WT), MALAT1 knockout (M-KO), NEAT1 knockout (N-KO), and NEAT1 knockdown (N-KD) mice was scraped to evaluate corneal epithelial and nerve regeneration rates. RNA sequencing of the corneal epithelium from WT and N-KO mice was performed 24 hours after debridement to determine the role of NEAT1. Quantitative PCR (qPCR) and ELISA were used to confirm the bioinformatic analysis. The effects of the cAMP signaling pathway were evaluated in N-KO and N-KD mice using SQ22536, an adenylate cyclase inhibitor. Results: Central corneal epithelial debridement in N-KO mice significantly promoted epithelial and nerve regeneration rates while suppressing inflammatory cell infiltration. Furthermore, the expression of Atp1a2, Ppp1r1b, Calm4, and Cngb1, which are key components of the cAMP signaling pathway, was upregulated in N-KO mice, indicative of its activation. Furthermore, the cAMP pathway inhibitor SQ22536 reversed the accelerated corneal epithelial wound healing in both N-KO and N-KD mice. Conclusions: NEAT1 deficiency contributes to epithelial repair during corneal wound healing by activating the cAMP signaling pathway, thereby highlighting a potential therapeutic strategy for corneal epithelial diseases.
Subject(s)
Corneal Diseases , Corneal Injuries , Epithelium, Corneal , Animals , Mice , Cornea , Cyclic Nucleotide-Gated Cation Channels , Nerve Tissue Proteins , Sodium-Potassium-Exchanging ATPase , Wound HealingABSTRACT
Hemimasticatory spasm is a very rare disorder of the trigeminal nerve characterized by paroxysmal involuntary contraction of the jaw-closing muscles. Although its cause is not fully known, vascular compression of the trigeminal nerve is thought to be involved. Magnetic resonance imaging (MRI) can indicate continuing vascular compression for hemimasticatory spasm. Here, we report a case of hemimasticatory spasm that was caused by single venous compression of the trigeminal nerve root on MRI and was confirmed by microvascular decompression surgery.
ABSTRACT
BACKGROUND: Coronary angiography-derived radial wall strain (RWS) is a newly developed index that can be readily accessed and describes the biomechanical features of a lesion. OBJECTIVES: The authors sought to investigate the association of RWS with fractional flow reserve (FFR) and high-risk plaque (HRP), and their relative prognostic implications. METHODS: We included 484 vessels (351 patients) deferred after FFR measurement with available RWS data and coronary computed tomography angiography. On coronary computed tomography angiography, HRP was defined as a lesion with both minimum lumen area <4 mm2 and plaque burden ≥70%. The primary outcome was target vessel failure (TVF), a composite of target vessel revascularization, target vessel myocardial infarction, or cardiac death. RESULTS: The mean FFR and RWSmax were 0.89 ± 0.07 and 11.2% ± 2.5%, respectively, whereas 27.7% of lesions had HRP, 15.1% had FFR ≤0.80. An increase in RWSmax was associated with a higher risk of FFR ≤0.80 and HRP, which was consistent after adjustment for clinical or angiographic characteristics (all P < 0.05). An increment of RWSmax was related to a higher risk of TVF (HR: 1.23 [95% CI: 1.03-1.47]; P = 0.022) with an optimal cutoff of 14.25%. RWSmax >14% was a predictor of TVF after adjustment for FFR or HRP components (all P < 0.05) and showed a direct prognostic effect on TVF, not mediated by FFR ≤0.80 or HRP in the mediation analysis. When high RWSmax was added to FFR ≤0.80 or HRP, there were increasing outcome trends (all P for trend <0.001). CONCLUSIONS: RWS was associated with coronary physiology and plaque morphology but showed independent prognostic significance.
Subject(s)
Fractional Flow Reserve, Myocardial , Humans , Coronary Angiography , Treatment Outcome , Heart , Computed Tomography AngiographyABSTRACT
OBJECTIVE: To explore the effect of nuclear factor erythroid 2-related factor 2 (Nrf 2) on microglial inflammatory response and proliferation after spinal cord injury (SCI) through the glyceraldehyde phosphate dehydrogenase (GAPDH) / Seven in absentia homolog 1 (Siah 1) signaling pathway. METHODS: Human microglia HMC3 was induced by lipopolysaccharide (LPS) to establish a SCI cell model. Microglia morphology after LPS stimulation was observed by transmission electron microscope (TEM), and cellular Nrf2, GAPDH/Siah1 pathway expression and cell viability were determined. Subsequently, the Nrf2 overexpression plasmid was transfected into microglia to observe changes in cell viability and GAPDH/Siah1 pathway expression. RESULTS: Microglia, mostly amoeba-like, were found to have enlarged cell bodies after LPS stimulation, with an increased number of cell branches, highly expressed Nrf2, GAPDH and Siah1, and decreased cell viability (P<0.05). Up-regulating Nrf2 inhibited the GAPDH/Siah1 axis, decreased inflammatory responses, and enhanced activity in post-SCI microglia (P<0.05). CONCLUSION: Up-regulating Nrf2 expression can reverse the inflammatory reaction of microglia after LPS stimulation and enhance their activity by inhibiting the GAPDH/Siah1 axis.
ABSTRACT
The utilization of biomass char was hindered by the low gasification activity due to thick ring structures and unclear gasification mechanism. Herein, the mechanism was elucidated by experimental and DFT to improve the activity. The results demonstrated that temperature increased the gasification activity but did not changed the order of gasification activity of samples. Pressure dominated the position of the highest point of instantaneous CH4 yield, and high pressure enhanced carbon conversion by 81.72 % and 7.32 times. Moreover, KNi exhibited an uppermost catalytic activity with the instantaneous CH4 yield 1.89 times higher than that of raw char at 750 °C. The formation of the CxNi structure lowered the activation barrier for the ring opening reaction. Possible transformation pathways of Ni species were as follows: Ni(NO3)2·6H2O â NiO â Ni. KNi changed the reaction pathways and the most energy-consuming step. The study could shed light on the hydrogasification reaction mechanism.
Subject(s)
Carbon Dioxide , Transition Elements , Carbon Dioxide/chemistry , Carbon , Temperature , Catalysis , BiomassABSTRACT
CpG oligodeoxynucleotides (ODNs) strongly activate the immune system after binding to toll-like receptor 9 (TLR9) in lysosome, which demonstrated significant potential in cancer immunotherapy. However, their therapeutic efficacy is limited by drawbacks such as rapid degradation and poor cellular uptake. Although encouraging progress have been made on developing various delivery systems for CpG ODNs, safety risks of the synthetic nanocarriers as well as the deficient CpG ODNs release within lysosome remain big obstacles. Herein, we developed a novel nanovector for lysosome-targeted CpG ODNs delivery and enhanced cancer immunotherapy. Natural glycogen was simply aminated (NH2-Gly) through grafting with diethylenetriamine (DETA), which was spherical in shape with diameter of approximately 40 nm. NH2-Gly possessed good biocompatibility. Cationic NH2-Gly complexed CpG ODNs well and protected them from nuclease digestion. NH2-Gly significantly enhanced the cellular uptake of CpG ODNs. Efficient CpG ODNs release was observed in the presence of α-glucosidase that mimicking the environment of lysosome. Consequently, NH2-Gly/CpG complexes triggered potent antitumor immunity and effectively inhibit the tumor growth without causing any toxic effect or tissue damages. This work highlights the promise of glycogen for lysosome-targeted on-command delivery of CpG ODNs, which brings new hope for precision cancer immunotherapy.
Subject(s)
Adjuvants, Immunologic , Neoplasms , Humans , Adjuvants, Immunologic/pharmacology , Oligodeoxyribonucleotides/pharmacology , Oligodeoxyribonucleotides/chemistry , Lysosomes , Immunotherapy , Neoplasms/drug therapyABSTRACT
The study reports the economic and sustainable syntheses of a lignin-based porous carbon (LPC) for CO2 capture application. The pH values of hydrothermal solution affected the polymerization and aromatization of spheroidization, with morphological changes from blocky to microsphere. In addition, the reliable mechanisms of CO2 adsorption were proposed by combining experiments with Gaussian16 simulations based on DFT. The electrostatic attraction of oxygen-containing functional groups and the diffusivity resistance of CO2 in the pores are the key factors for the CO2 adsorption. âThe carboxyl groups have the strongest electrostatic attraction to CO2. LPC-pH 1 has the highest carboxyl group content, possessing a CO2 adsorption capacity of up to 5.10 mmol/g at 0â, 1 bar. Furthermore, CO2 diffusion resistance became a main factor as the adsorption temperature increases. The innovative combination of quantum chemical calculations and microscopic properties provides a viable pathway for an insight into the future control of lignin-based carbon formation.
Subject(s)
Carbon Dioxide , Lignin , Carbon Dioxide/chemistry , Lignin/chemistry , Adsorption , Porosity , Microspheres , Hydrogen-Ion ConcentrationABSTRACT
The electrochemical properties of corn starch (CS)-based hydrothermal carbon microsphere (CMS) electrode materials for supercapacitor are closely related to their structures. Herein, cetyltrimethyl ammonium bromide (CTAB) was used as a soft template to form the corn starch (CS)-based carbon microspheres with radial hollow structure in the inner and middle layers by hydrothermal and sol-gel method. Due to the introduction of multi-layer hollow structure of carbon microsphere, more micropores were produced during CO2 activation, which increased the specific surface area and improved the capacitance performance. Compared to commercial activated carbon, the four different morphologies of corn starch CMS had better electrochemical performances. Consequently, the proposed CO2-(CTAB)-CS-CS exhibits a high discharge specific capacitance of 242.5F/g at 1 A/g in three-electrode system with 6 M KOH electrolyte, better than commercial activated carbon with 208.5F/g. Moreover, excellent stability is achieved for CO2-(CTAB)-CS-CS with approximately 97.14 % retention of the initial specific capacitance value after 10,000 cycles at a current density of 2 A/g, while the commercial activated carbon has 86.96 % retention. This implies that the corn starch-based multilayer hollow CMS could be a promising electrode material for high-performance supercapacitors.
ABSTRACT
As a basic parameter of the intracellular microenvironment, viscosity is closely related to the development of cancer. Thus, it is necessary to utilize a sensitive tool to visualize the viscosity in tumor cells and mice, which is helpful for the diagnosis of cancer. Herein, a novel dual-modal probe (IX-V) that has a near-infrared fluorescence (NIRF) and photoacoustic (PA) response to viscosity is synthesized. In low viscosity media, the probe has no fluorescence. With the increase of viscosity, the fluorescence is produced in the near-infrared region due to the inhibition of the TICT process. At the same time, the probe shows different photoacoustic (PA) signals in different viscosity media. Most notably, the viscosity in tumor cells has been imaged successfully by the application of IX-V, and the probe can effectively distinguish cancer cells from normal cells co-cultured in one dish by the difference of fluorescence intensity. In addition, the probe has been used for dual-modal imaging (NIRF and PA) of viscosity in tumor mice, which provides a tool for exploring the relationship between viscosity and diseases. That is to say, IX-V can achieve complementary imaging effects and has great application prospects in the tumor diagnosis.
Subject(s)
Fluorescent Dyes , Neoplasms , Mice , Animals , Viscosity , Cell Line, Tumor , Fluorescence , Optical Imaging/methods , Neoplasms/diagnostic imagingABSTRACT
Synthesis of upconversion nanoparticles (UCNPs)-metal halide perovskites (MHPs) heterostructure is garnered immense attentions due to their unparalleled photophysical properties. However, the obvious difference in their structural forms makes it a huge challenge. Herein, hexagonal ß-NaYF4 and hexagonal Cs4PbBr6 are filtrated to construct the UCNP/MHP heterostructural luminescent material. The similarity in their crystal structures facilitate the heteroepitaxial growth of Cs4PbBr6 on the surface of ß-NaYF4 NPs, leading to the formation of high-quality ß-NaYF4:Yb,Tm/Cs4PbBr6 core/shell nanocrystals (NCs). Interestingly, this heterostructure endows the core/shell NCs with typically narrow-band green emission centered at 524 nm under 980 nm excitation, which should be attributed to the Förster resonance energy transfer (FRET) from Tm3+ to Cs4PbBr6. It is noteworthy that the FRET efficiency of ß-NaYF4:Yb,Tm/Cs4PbBr6 core/shell NCs (58.33%) is much higher than that of the physically mixed sample (1.84%). In addition, the reduced defect density, lattice anchoring effect, as well as diluted ionic bonding proportion induced by the core/shell structure further increase the excellent water-resistance and thermal cycling stability of Cs4PbBr6. These findings open up a new way to construct UCNP/MHP heterostructure with better multi-code luminescence performance and stability and promote its wide optoelectronic applications.
ABSTRACT
Cysteine is an important biological thiol and is closely related to cancer. It remains a challenge to develop a probe that can provide long-term fluorescence detection and imaging of Cys in cells as well as in living organisms. Here, a solid-state fluorophore HTPQ is combined with an acrylate group to construct a solid-state fluorescent probe HTPQC for Cys recognition. The fluorescence of the probe is quenched when the photoinduced electron transfer (PET) process is turned on and the excited-state intramolecular proton transfer (ESIPT) process is turned off. In the presence of Cys, an obvious solid-state fluorescence signal can be observed. The double quenching mechanism makes the probe HTPQC have the advantages of high sensitivity, good selectivity, and high contrast of biological imaging. Due to low cytotoxicity, the probe HTPQC can be used to detect exogenous and endogenous Cys in living cells and is capable of imaging over long periods of time. By making full use of long wavelengths, the probe can be applied for the detection of Cys levels in tumor mice and equipped with the ability to conduct long-term imaging in vivo.
Subject(s)
Cysteine , Fluorescent Dyes , Humans , Animals , Mice , Fluorescent Dyes/toxicity , HeLa Cells , Sulfhydryl Compounds , ProtonsABSTRACT
The catalytic gasification of petroleum coke with different ratios of K2CO3 was investigated by a thermogravimetric analyzer (TGA) using the non-isothermal method. The initial, peak, and final gasification temperatures of the petroleum coke decreased greatly as the amount of K2CO3 increased, and the catalytic reaction became saturated at a concentration of K+ higher than 5 mmol/g; with the further increase in catalyst; the gasification rate varied slightly, but no inhibition effect was observed. The vaporization of the catalyst was confirmed during the gasification at high temperatures. The structural evolution of the residual coke with different carbon conversions was examined by X-ray diffraction (XRD), Raman spectroscopy, and N2 adsorption analyses during gasification with and without the catalyst. The results showed that the carbon crystallite structure of the residual coke varied in the presence of the catalyst. As the carbon conversion increased, the structure of the residual coke without the catalyst became more ordered, and the number of aromatic rings decreased, while the graphitization degree of the residual coke in the presence of the catalyst decreased. Meanwhile, the surface area and pore volume of petroleum coke increased in the gasification process of the residual coke, irrespective of the presence of the catalyst. However, the reactivity of the residual coke did not change much with the variation in the carbon and pore structure during the reaction.
ABSTRACT
Although hydrogen sulfide (H2S) is a well-known toxic gas, its vital role as a gas transmitter in various physiological and pathological processes of living systems cannot be ignored. Relevant investigations indicate that endogenous H2S is involved in the development of ulcerative colitis pathology and is overexpressed in ulcerative colitis, and hence can be considered as an ulcerative colitis biomarker. Herein, an isophorone-xanthene-based NIR fluorescent probe (IX-H2S) was constructed to image H2S. Owing to its large conjugated structure, the probe exhibits a near-infrared emission wavelength of 770 nm with a large Stokes shift (186 nm). Moreover, IX-H2S has excellent selectivity for the detection of H2S without interference from other analytes including thiols. In addition, the probe has been successfully applied not only in fluorescence imaging of endogenous and exogenous H2S in living cells, but also in imaging of H2S in normal and ulcerative colitis mice. Encouraged by the eminent performance, IX-H2S is expected to be a potent "assistant" for the diagnosis of ulcerative colitis.