Reconstruction Filters Improving the Spatial Resolution and Signal-to-Noise Ratio of Surface Plasmon Resonance Microscopy.

Benefitting from high sensitivity, real-time, and label-free imaging, surface plasmon resonance microscopy (SPRM) has become a powerful tool for dynamic detection of nanoparticles. However, the evanescent propagation of surface plasmon polaritons (SPPs) induces interference between scattered and launched SPPs, which deteriorates the spatial resolution and signal-to-noise ratio (SNR). Due to the simplicity and fast processing, image reconstruction based on deconvolution has shown the feasibility of improving the spatial resolution of SPRM imaging. Retrieving the particle scattering from SPRM interference imaging by filters is crucial for reconstruction. In this work, we illustrate the effect of filters extracting SPP scattering of nanoparticles with different sizes and shapes for reconstruction. The results indicate that the optimum filters are determined by the material of nanoparticles instead of particle sizes. The reconstruction of single Au and PS nanospheres as well as Ag nanowires with optimum filters is achieved. The reconstructed spatial resolution is improved to 254 nm, and the SNR is increased by 8.1 times. Our research improves the quality of SPRM imaging and provides a reliable method for fast detection of particles with diverse sizes and shapes.

Directional surface plasmon polariton scattering using single magnetic nanoparticles.

Directional surface plasmon polaritons (SPPs) are expected to promote the energy efficiency of plasmonic devices, via limiting the energy in a given spatial domain. The directional scattering of dielectric nanoparticles induced by the interference between electric and magnetic responses presents a potential candidate for directional SPPs. Magnetic nanoparticles can introduce permeability as an extra manipulation, whose directional scattered SPPs have not been investigated yet. In this work, we demonstrated the directional scattered SPPs by using single magnetic nanoparticles via simulation and experiment. By increasing the permeability and particle size, the high-order TEM modes are excited inside the particle and induce more forward directional SPPs. It indicated that the particle size manifests larger tuning range compared with the permeability. Experimentally, the maximum forward-to-backward (F-to-B) SPP scattering intensity ratio of 118.52:1 is visualized by using a single 1 µm Fe3O4 magnetic nanoparticle. The directional scattered SPPs of magnetic nanoparticles are hopeful to improve the efficiency of plasmonic devices and pave the way for plasmonic circuits on-chip.

Two-dimensional Janus SbTeBr/SbSI heterostructures as multifunctional optoelectronic systems with efficient carrier separation.

The stacking of two-dimensional (2D) materials is a highly effective approach in the design of high-performance optoelectronic devices. In this study, we propose a novel Janus monolayer-based 2D/2D van der Waals heterostructure (vdWH) called SbTeBr/SbSI. Starting from its most stable binding configuration, we systematically examined its electronic, optical, mechanical and dynamical properties. The SbTeBr/SbSI vdWH exhibits a type II band arrangement, with an indirect bandgap of 1.28 eV and strong light absorption capabilities in the visible range, achieving an absorption coefficient of 4 × 105 cm-1. These desirable properties suggest that SbTeBr/SbSI holds promise as a material for solar cells, potentially achieving a power conversion efficiency of 8.3%. The dipole-induced electric field in the SbTeBr/SbSI vdWH leads to significant differences in the mobilities of different carriers, which is a critical aspect in suppressing the recombination of photogenerated carriers. Additionally, according to the simulations of nonadiabatic molecular dynamics, a long electron-hole recombination time of 133 ps is predicted. Thus, the SbTeBr/SbSI heterostructure enables efficient charge separation, demonstrating its potential as a high-performance optoelectronic material.

An oral phenylacrylic acid derivative suppressed hepatic stellate cell activation and ameliorated liver fibrosis by blocking TGF-ß1 signalling.

BACKGROUND AND AIMS: Liver fibrosis is an excessive wound-healing response governed by activated hepatic stellate cells (HSCs). To date, there is no drug available for liver fibrosis. Although ferulic acid (FA) has multiple pharmacological functions, its anti-hepatic fibrosis activity is weak. Based on the activity modification of the FA structure, we synthesized a series of phenylacrylic derivatives and found a superior compound, FA11. In this study, we investigated its antifibrotic effect and mechanism. METHODS: Activated HSC and CCl4 -induced mouse liver fibrosis were established and followed by FA11 treatment. Cell viability was measured by CCK-8 assay. Apoptosis and cell cycle analysis were conducted by flow cytometry. Western blot and Real-time qPCR were used to examine the expression of fibrotic and M1/M2-type macrophages markers. Degree of liver fibrosis was shown by histological staining. RESULTS: In vitro, FA11 inhibited TGF-ß1-induced LX-2 proliferation and led to apoptosis and cycle arrest. Furthermore, elevation of fibrotic markers in TGF-ß1-induced LX-2 and primary activated HSC was reversed by FA11. In vivo, FA11 administration alleviated collagen deposition and blocked HSC activation and epithelial-mesenchymal transition (EMT). Additionally, FA11 reduced macrophage infiltration in fibrotic liver and prevented macrophage polarization to a profibrotic phenotype. Meanwhile, the systemic toxicity of CCl4 was also ameliorated by FA11. Mechanistically, FA11 reversed the phosphorylation of canonical and noncanonical TGF-ß1 signalling, as well as FGFR1 signalling. CONCLUSIONS: We reported an oral phenylacrylic acid derivative, FA11, which showed excellent antifibrotic activity and was expected to be an anti-hepatic fibrosis candidate.

A parylene-mediated plasmonic-photonic hybrid fiber-optic sensor and its instrumentation for miniaturized and self-referenced biosensing.

With the development of advanced nanofabrication techniques over the past decades, different nanostructure-based plasmonic fiber-optic sensors have been developed and have presented a low limit of detection for various biomolecules. However, owing to both the dependence on complex equipment and the trade-off between the fabrication cost and sensing performance, nanostructured plasmonic fiber-optic sensors are rarely used outside laboratories. To facilitate wider application of the plasmonic fiber-optic sensors, a parylene-mediated hybrid plasmonic-photonic cavity-based sensor was developed. Compared with a similar plasmonic sensor which only works in the plasmonic mode, the proposed hybrid sensor shows a higher reproducibility (CV < 2.5%) due to its resistance to fabrication variations. Meanwhile, a self-referenced detection mechanism and a novel miniaturized system were developed to adapt to the hybrid resonance sensor. The entire system only has a weight of 263 g, and a size of 12 cm × 10 cm × 8 cm, and is especially suitable for outdoor applications in a handheld manner. In experiments, a high refractive index sensitivity of 3.148 RIU-1 and real-time biomolecule monitoring at nanomolar concentrations were achieved by the proposed system, further confirming the potential of the miniaturized system as a candidate for point-of-care health diagnostics outside laboratories.

Effects of nanoparticle sizes, shapes, and permittivity on plasmonic imaging.

Plasmonic imaging has exhibited superiority in label-free and fast detection to single nanoparticles due to its high sensitivity and high temporal resolution, which plays an important role in environmental monitoring and biomedical research. As containing plenty of information associated with particle features, plasmonic imaging has been used for identifying the particle sizes, shapes, and permittivity. Yet, the effects of the nanoparticle features on plasmonic imaging are not investigated, which hinders the in-depth understanding to plasmonic imaging and its applications in particle identification. In this work, we analyzed five types of nanoparticles, including polystyrene (PS), Au, silicon nanospheres as well as PS and Ag nanowires. We illustrated the effects of nanoparticle sizes, shapes, and permittivity on spatial resolution, imaging contrast, and interference fringes. We found that nanoparticle sizes and permittivity influenced the imaging contrast. Via introducing size parameter relevant to interference fringes, the connection between particle shape and reduction rate of size parameter is built, and the effects of particle shapes on the interference patterns are revealed. Our research provides a basis for improving the plasmonic imaging and presents guidance for applications on particle identification in nano-detection, biosensor, and environmental monitoring.

Nifuroxazide ameliorates pulmonary fibrosis by blocking myofibroblast genesis: a drug repurposing study.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a serious interstitial lung disease with a complex pathogenesis and high mortality. The development of new drugs is time-consuming and laborious; therefore, research on the new use of old drugs can save time and clinical costs and even avoid serious side effects. Nifuroxazide (NIF) was originally used to treat diarrhoea, but more recently, it has been found to have additional pharmacological effects, such as anti-tumour effects and inhibition of inflammatory diseases related to diabetic nephropathy. However, there are no reports regarding its role in pulmonary fibrosis. METHODS: The therapeutic effect of NIF on pulmonary fibrosis in vivo was measured by ELISA, hydroxyproline content, H&E and Masson staining, immunohistochemistry (IHC) and western blot. Immune cell content in lung tissue was also analysed by flow cytometry. NIF cytotoxicity was evaluated in NIH/3T3 cells, human pulmonary fibroblasts (HPFs), A549 cells and rat primary lung fibroblasts (RPLFs) using the MTT assay. Finally, an in vitro cell model created by transforming growth factor-ß1 (TGF-ß1) stimulation was assessed using different experiments (immunofluorescence, western blot and wound migration assay) to evaluate the effects of NIF on the activation of NIH/3T3 and HPF cells and the epithelial-mesenchymal transition (EMT) and migration of A549 cells. RESULTS: In vivo, intraperitoneal injection of NIF relieved and reversed pulmonary fibrosis caused by bleomycin (BLM) bronchial instillation. In addition, NIF inhibited the expression of a variety of cellular inflammatory factors and immune cells. Furthermore, NIF suppressed the activation of fibroblasts and EMT of epithelial cells induced by TGF-ß1. Most importantly, we used an analytical docking experiment and thermal shift assay to further verify that NIF functions in conjunction with signal transducer and activator of transcription 3 (Stat3). Moreover, NIF inhibited the TGF-ß/Smad pathway in vitro and decreased the expression of phosphorylated Stat3 in vitro and in vivo. CONCLUSION: Taken together, we conclude that NIF inhibits and reverses pulmonary fibrosis, and these results support NIF as a viable therapeutic option for IPF treatment.

Photogenerated carrier dynamics at the B4C3/g-C3N4 interface.

Developing van der Waals (vdW) heterostructures is an excellent approach for optimizing exceptional optoelectronic and photocatalytic properties of materials; therefore, researching the interface dynamics of charge carriers at the two-dimensional vdW heterojunction is of great significance. In this work, we perform time-dependent ab initio non-adiabatic molecular dynamics simulations to study the dynamics of charge transfer at the B4C3/g-C3N4 heterostructure. The simulations show that the charge transfer between B4C3/g-C3N4 layers is mainly caused by the non-adiabatic mechanism. The non-adiabatic mechanism leads to a higher charge-transfer efficiency and slows down the process of interlayer electron-hole recombination, thereby promoting the separation of photogenerated electron-hole pairs. Our investigation provides essential insights into understanding the dynamics of charge transfer for the B4C3/g-C3N4 heterostructure, which provides guidance for photocatalytic water splitting and optoelectrical applications.

Design, synthesis and biological evaluation of a series of novel pyrrolo[2,3-d]pyrimidin/pyrazolo[3,4-d]pyrimidin-4-amine derivatives as FGFRs-dominant multi-target receptor tyrosine kinase inhibitors for the treatment of gastric cancer.

Gastric cancer is the second most lethal cancer across the world. With the progress in therapeutic approaches, the 5-year survival rate of early gastric cancer can reach > 95%. However, the prognosis and survival time of advanced gastric cancer is still somber. Therefore, more effective targeted therapies for gastric cancer treatment are urgently needed. FGFR, VEGFR and other receptor tyrosine kinases have recently been suggested as potential targets for gastric cancer treatment. We herein report the discovery of pyrrolo[2,3-d]pyrimidin/pyrazolo[3,4-d]pyrimidin-4-amine derivatives as a new class of FGFRs-dominant multi-target receptor tyrosine kinase inhibitors. SAR assessment identified the most active compounds 8f and 8k, which showed excellent inhibitory activity against a variety of receptor tyrosine kinases. Moreover, 8f and 8k displayed excellent potency in the SNU-16 gastric cancer cell line. Furthermore, 8f and 8k could inhibit FGFR1 phosphorylation and downstream signaling pathways as well as induce cell apoptosis. In vivo, 8f and 8k suppress tumor growth in the SNU-16 xenograft model without inducing obvious toxicity. These findings raise the possibility that compounds 8f and 8k might serve as potential agents for the treatment of gastric cancer.

A rare case of bladder cancer that metastasized to brain, heart, and lung lymph nodes benefited from immunotherapy.

Bladder cancer is a common malignant tumor of the genitourinary system, with the primary cause of death being metastasis. The most common metastatic sites are the lymph nodes, liver, lung, bone, peritoneum, pleura, kidney, adrenal gland, and the intestine. Brain and heart metastases are rare. In this report, we describe a patient who had pulmonary lymph node metastases more than a year after being diagnosed with bladder cancer, followed by brain and cardiac metastases more than two years later. Following the failure of standard first-line chemotherapy, the patient accepted 6 cycles of tislelizumab immunotherapy. The re-examination revealed that the bilateral frontal brain metastases had vanished, the right temporal lobe metastases had been greatly decreased, the neurological symptoms had been alleviated, and the cardiac metastases had disappeared. This is a rare clinical case with encouraging effects of tislelizumab and can serve as a model for the treatment of similar patients.

Locally excited surface plasmon resonance for refractive index sensing with high sensitivity and high resolution.

An angle-interrogated surface plasmon resonance (SPR) sensor based on a prism-coupled configuration has been extensively applied in biomedicine, environment monitoring, and food safety. Yet, the low sensitivity and low spatial resolution impede its further development. In this Letter, we investigated objective-coupled locally excited SPR for refractive index (RI) sensing with high sensitivity and high resolution. Through theoretical analysis, the SPR angle was retrieved from back focal plane imaging, which was highly correlated to the RI of the surrounding medium. Experimentally, a RI sensitivity of 77.41° refractive index unit (RIU)-1 was achieved with a detection range of 0.068 RIU when using glucose solutions for the demonstration. Furthermore, we acquired the spatial resolution of the configuration being 290 nm, and the RI measurement to a polydimethylsiloxane droplet with high spatial resolution was implemented. As a result, compared with the classical prism-coupled configuration, the locally excited SPR provides a method to achieve RI sensing with high sensitivity and high resolution.

Epigenetic regulation in fibrosis progress.

Fibrosis, a common process of chronic inflammatory diseases, is defined as a repair response disorder when organs undergo continuous damage, ultimately leading to scar formation and functional failure. Around the world, fibrotic diseases cause high mortality, unfortunately, with limited treatment means in clinical practice. With the development and application of deep sequencing technology, comprehensively exploring the epigenetic mechanism in fibrosis has been allowed. Extensive remodeling of epigenetics controlling various cells phenotype and molecular mechanisms involved in fibrogenesis was subsequently verified. In this review, we summarize the regulatory mechanisms of DNA methylation, histone modification, noncoding RNAs (ncRNAs) and N6-methyladenosine (m6A) modification in organ fibrosis, focusing on heart, liver, lung and kidney. Additionally, we emphasize the diversity of epigenetics in the cellular and molecular mechanisms related to fibrosis. Finally, the potential and prospect of targeted therapy for fibrosis based on epigenetic is discussed.

The high power conversion efficiency of a two-dimensional GeSe/AsP van der Waals heterostructure for solar energy cells.

Constructing a van der Waals heterostructure is a practical way to promote the conversion efficiency of solar energy. Here, we demonstrate the efficient performance of a GeSe/AsP heterostructure in solar energy cells based on the first-principles calculations. The electronic properties, optical absorption, and optoelectronic properties are calculated to evaluate the efficiency of the newly designed heterostructure. The results indicate that the GeSe/AsP heterostructure possesses a type-II band alignment with an indirect bandgap of 1.10 eV, which greatly promotes the effective separation of photogenerated carriers. Besides, an intrinsic electric field is formed in the direction from the AsP to GeSe monolayer, which is beneficial to prevent the recombination of the photogenerated electron-hole pair. Simultaneously, a strong optical absorption is observed in the visible light range. The predicted power conversion efficiency (PCE) of the GeSe/AsP heterostructure is 16.0% and can be promoted to 17.3% by applying 1% biaxial compression strain. The present results indicate that the GeSe/AsP heterostructure is a promising candidate material for high-performance solar cells.

Detecting the morphology of single graphene sheets by dual channel sampling plasmonic imaging.

Due to their excellent physical and chemical properties, graphene sheets are widely used in industry, which makes detection important to guarantee their performance. Atomic force microscopy, scanning electron microscopy, and Raman spectroscopy are the most common detection methods, which is either time-consuming or easily destructive. In this work, we presented a fast and nondestructive method to detect single graphene sheets by using plasmonic imaging. Dual channel sampling plasmonic imaging combining the image processing algorithm is used to improve the deterioration from propagation length of surface plasmon polaritons and reconstruct the complete morphology of single graphene sheets. The fast and nondestructive detection method paves the way to applications of graphene, and can be extended to the detections of two-dimensional materials, single biological molecule, viruses, and nanomaterials.

Detecting a single nanoparticle by imaging the localized enhancement and interference of surface plasmon polaritons: erratum.

In this erratum, the function ${\lambda _{{\rm SPP}}}$λSPP in the third page of Opt. Lett.44, 5707 (2019)OPLEDP0146-959210.1364/OL.44.005707 has been corrected.

Galangin ameliorated pulmonary fibrosis in vivo and in vitro by regulating epithelial-mesenchymal transition.

Pulmonary fibrosis (PF) is a disease that is characterized by abnormal epithelial-mesenchymal transition (EMT) and persistent inflammatory injury, with high mortality and poor prognosis, but the current therapies are accompanied by certain adverse side effects. In this study, we investigated the role of galangin (GA), an anti-inflammatory and anti-tumoral phytochemical extracted from galangal, in preventing and curing bleomycin (BLM)-induced pulmonary fibrosis and the underlying mechanism. Histopathological staining confirmed that GA dramatically moderated bleomycin-induced pulmonary fibrosis in mice. Compared with the vehicle treatment, GA treatment inhibited the expression of vimentin and increased the expression of E-cadherin. The expression of α-Smooth muscle actin (α-SMA), which is a myofibroblast marker, was also suppressed. In addition, GA diminished the increase in the numbers of CD4+CD69+ and CD8+CD69+ T cells and dendritic cells induced by bleomycin, and reduced the residence of inflammatory cells in the lung tissues. Notably, GA inhibited the TGF-ß1-induced EMT and fibroblast differentiation in vitro, which further confirmed the potential protective effect of GA on pulmonary fibrosis. Taken together, our results suggest that GA exerts a beneficial effect on bleomycin-induced pulmonary fibrosis by attenuating EMT and inflammatory damage and may have prevent potential of pulmonary fibrosis.

Cryptotanshinone reverses the epithelial-mesenchymal transformation process and attenuates bleomycin-induced pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a fibrotic interstitial pneumonia that causes pulmonary tissue damage and functional impairment. To investigate the effects of cryptotanshinone on pulmonary fibrosis, the expression of NIH/3T3, HPF, and rat primary pulmonary fibroblasts was measured and found to be inhibited by CPT in a time- and concentration-dependent manner, and the upregulation of α-SMA expression in NIH/3T3 and HPF cells, which had been stimulated by TGFß-1, was decreased after CPT administration. We observed that CPT could reverse the increase in α-SMA expression and vimentin and the decrease in E-cad expression in A549 cells, which had been induced by 5 ng/mL TGFß-1, indicating that CPT has inhibitory effects in the EMT process. A BLM-induced pulmonary fibrosis model was established in C57BL/6 mice. The lung coefficient and hydroxyproline content increased significantly in the BLM-induced group and were decreased in the CPT-treated group. The expression levels of collagen-I and α-SMA and the phosphorylation level of Stat3 were significantly increased, and CPT treatment decreased these levels. Furthermore, the results from the flow cytometry analysis indicated that, in lung tissues, the frequencies of MDSCs, macrophages, DCs and T cells were considerably increased in the BLM-induced group, while CPT treatment reduced these immunocyte populations.

Detecting a single nanoparticle by imaging the localized enhancement and interference of surface plasmon polaritons.

Label-free single-nanoparticle detection is crucial for the fast detection of nanoparticles and viruses in environmental monitoring and biological sciences. In this Letter, benefiting from the leakage radiation that transforms the near-field surface plasmon polariton (SPP) distribution along the interface to the far field, we demonstrated the plasmonic imaging of single polystyrene nanoparticles with a particle size down to 39 nm. The imaging is composed of the localized enhancement and interference of SPPs. The localized enhancement is the result of the accumulation of charges around the nanoparticle, and it is connected to the size and refractive index of nanoparticles. The interference is induced by the coupling between the incident SPPs and the scattered SPPs, verified by extracting the interference fringe periodicity to be half of the SPP wavelength. Our study provides an in-depth physical understanding of plasmonic imaging of single nanoparticles, which paves the way for a fast identification of nanomaterials.

Natural product pectolinarigenin exhibits potent anti-metastatic activity in colorectal carcinoma cells in vitro and in vivo.

Colorectal carcinoma (CRC) is one of the most common cancers with high metastatic potential, explaining why identifying new drug candidates that inhibit tumour metastasis is an urgent need. The aim of this study was to evaluate the biological activities of pectolinarigenin (PEC, a natural flavonoid present in Cirsium chanroenicum) in CRC in vitro and in vivo and to determine its underlying mechanism of action. Here, we observed that treatment with PEC could inhibit cell viability and induce apoptosis in cancer cells in a concentration- and time-dependent manner. The occurrence of apoptosis was associated with activation of caspase-3 and Bax and decreased expression of Bcl-2. In addition, PEC markedly impaired CRC cell migration and invasion by downregulating the expression of matrix metalloproteinase (MMP-9) and phosphorylated-Stat3Tyr705. Moreover, our studies showed that PEC inhibited abdominal metastasis models of murine colorectal cancer. In addition, histological and immunohistochemical analyses revealed a decrease in Ki67-positive cells, MMP9-positive cells and p-Stat3Tyr705 cells upon treatment with PEC compared to control samples. Furthermore, PEC reduced the number of myeloid-derived suppressor cells (MDSCs) in the blood and tumours, which was accompanied by the increased infiltration of CD8+T cells in the blood. Taken together, our findings suggested that PEC could be used as a natural drug to inhibit CRC metastasis.

Niclosamide - encapsulated lipid nanoparticles for the reversal of pulmonary fibrosis.

Pulmonary fibrosis (PF) is a serious and progressive fibrotic interstitial lung disease that is possibly life-threatening and that is characterized by fibroblast accumulation and collagen deposition. Nintedanib and pirfenidone are currently the only two FDA-approved oral medicines for PF. Some drugs such as antihelminthic drug niclosamide (Ncl) have shown promising therapeutic potentials for PF treatment. Unfortunately, poor aqueous solubility problems obstruct clinical application of these drugs. Herein, we prepared Ncl-encapsulated lipid nanoparticles (Ncl-Lips) for pulmonary fibrosis therapy. A mouse model of pulmonary fibrosis induced by bleomycin (BLM) was generated to assess the effects of Ncl-Lips and the mechanisms of reversing fibrosis in vivo. Moreover, cell models treated with transforming growth factor ß1 (TGFß1) were used to investigate the mechanism through which Ncl-Lips inhibit fibrosis in vitro. These findings demonstrated that Ncl-Lips could alleviate fibrosis, consequently reversing the changes in the levels of the associated marker. Moreover, the results of the tissue distribution experiment showed that Ncl-Lips had aggregated in the lung. Additionally, Ncl-Lips improved the immune microenvironment in pulmonary fibrosis induced by BLM. Furthermore, Ncl-Lips suppressed the TGFß1-induced activation of fibroblasts and epithelial-mesenchymal transition (EMT) in epithelial cells. Based on these results, we demonstrated that Ncl-Lips is an efficient strategy for reversing pulmonary fibrosis via drug-delivery.