Passively Q-switched Nd3+ solid-state lasers with hexakis-[(trimethylsilyl)ethynyl]benzene and graphdiyne as saturable absorbers.

In this paper, two-dimensional Graphdiyne and Hexakis-[(trimethylsilyl)ethynyl]benzene nanosheets were prepared using the liquid-phase exfoliation method and were then successfully applied to 1.06 µm passively Q-Switched all-solid-state lasers. The Hexakis-[(trimethylsilyl)ethynyl]benzene was applied for the first time in passively Q-Switched all-solid-state lasers, as we know. For Graphdiyne, the Q-Switched pulse achieved a narrowest pulse width of 415 ns, a maximum repetition frequency of 244.2 kHz, a maximum pulse energy of 133.53 nJ, and peak power of 321.77 mW was obtained. While, the narrowest pulse width, maximum repetition frequency, maximum pulse energy, and peak power for Hexakis-[(trimethylsilyl)ethynyl]benzene are approximately 398.4 ns, 297.1 kHz, 89.61 nJ, and 220.39 mW respectively. The findings demonstrate the promising potential of both candidates as saturable absorbers for signal modulation in solid-state lasers.

The role of exosomes in cancer-related programmed cell death.

Cancer arises from the growth and division of uncontrolled erroneous cells. Programmed cell death (PCD), or regulated cell death (RCD), includes natural processes that eliminate damaged or abnormal cells. Dysregulation of PCD is a hallmark of cancer, as cancer cells often evade cell death and continue to proliferate. Exosomes nanoscale extracellular vesicles secreted by different types of cells carrying a variety of molecules, including nucleic acids, proteins, and lipids, to have indispensable role in the communication between cells, and can influence various cellular processes, including PCD. Exosomes have been shown to modulate PCD in cancer cells by transferring pro- or antideath molecules to neighboring cells. Additionally, exosomes can facilitate the spread of PCD to surrounding cancer cells, making them promising in the treatment of various cancers. The exosomes' diagnostic potential in cancer is also an active area of research. Exosomes can be isolated from a wide range of bodily fluids and tissues, such as blood and urine, and can provide a noninvasive way to monitor cancer progression and treatment response. Furthermore, exosomes have also been employed as a delivery system for therapeutic agents. By engineering exosomes to carry drugs or other therapeutic molecules, they can be targeted specifically to cancer cells, reducing toxicity to healthy tissues. Here, we discussed exosomes in the diagnosis and prevention of cancers, tumor immunotherapy, and drug delivery, as well as in different types of PCD.

Transferable microfiber laser arrays for high-sensitivity thermal sensing.

Functional microfibers have attracted extensive attention due to their potential in health monitoring, radiation cooling, power management and luminescence. Among these, polymer fiber-based microlasers have plentiful applications due to their merits of full color, high quality factor and simple fabrication. However, developing a facile approach to fabricate stable microfiber lasing devices for high-sensitivity thermal sensing is still challenging. In this research, we propose a design of a stable and transferable membrane inlaid with whispering-gallery-mode plasmon hybrid microlaser arrays for thermal sensing. By integrating plasmonic gold nanorods with polymer lasing microfiber arrays that are embedded in the polydimethylsiloxane matrix, whispering-gallery-mode lasing arrays with high quality are achieved. Based on the thermo-optical effect of the membrane, a tuning range of 1.462 nm for the lasing peak shift under temperature variation from 30.6 °C to 38.7 °C is obtained. The ultimate thermal sensing sensitivity can reach up to 0.181 nm °C-1 and the limit of detection is 0.131 °C, with a high figure of merit of 2.961 °C-1. Moreover, a stable laser linewidth can be maintained within the tuning range due to plasmon-improved photon confinement and PDMS-reduced scattering loss. This work is expected to provide a facile approach for the fabrication of high-sensitivity on-chip thermometry devices.

BaLa5V2O3N7: a novel anti-perovskite oxynitride for electrode applications.

The exploration of transition metal oxynitrides has garnered significant interest due to their intriguing property diversity. Herein, we present a promising new transition metal oxynitride BaLa5V2O3N7, which features an anti-perovskite structure type. This unique structural configuration endows the material with remarkable conductivity, particularly at low temperatures, paving the way for the material to be used in a wide range of technological applications.

Excellent ultraviolet optical limiting properties of Se nanosheets.

Selenium (Se) is located in the fourth period of the periodic table in group VIA (element 34). In this experiment, three different solvents (isopropyl alcohol, N-methyl-2-pyrrolidone, and ethanol) were used to prepare the two-dimensional Se nanosheets, which were manufactured by the liquid phase exfoliation method with a thickness of 3.35-4.64 nm and a transverse scale of several hundred nanometers. The nonlinear absorption properties at 355, 532, and 1064 nm were studied using the open apertureZ-scan technique. Final results showed that Se nanosheets exhibited optical limiting (OL) effect in all three wavebands and three solvents, and had large two-photon absorption coefficients, especially in ultraviolet (UV) waveband. Which proved that Se nanosheets had great potential application as excellent OL materials in UV waveband. Our research broadens the path for the semiconductor field of Se, inspires the application of Se in nonlinear optics field.

Serum metabolomics analysis revealed metabolic disorders in Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is by now the second of the most prevalent neurodegenerative diseases in the world, and its incidence is increasing rapidly as the global population ages, with 14.2 million PD patients expected worldwide by 2040. METHODS: We gathered a completion of 45 serum samples, including 15 of healthy controls and 30 from the PD group. We used non-targeted metabolomics analysis based on liquid chromatography-mass spectrometry to identify the molecular changes in PD patients, and conducted bioinformatics analysis on this basis to explore the possible pathogenesis of PD. RESULTS: We found significant metabolomics changes in the levels of 30 metabolites in PD patients compared with healthy controls. CONCLUSION: Lipids and lipid-like molecules accounted for the majority of the 30 differentially expressed metabolites. Also, pathway enrichment analysis showed significant enrichment in sphingolipid metabolic pathway. These assessments can improve our perception on the underlying mechanism of PD as well as facilitate a better targeting on therapeutic interventions.

Low Dimensional Nanostructure-Assisted Long-Range Surface Plasmon Resonance Sensors With High Figure of Merit.

Long-range surface plasmon resonance (LRSPR) sensors have been extensively studied by virtue of their extremely narrow full width at half maxima (FWHM) characteristics, but their low sensitivity remains an important factor limiting the figure of merit (FOM), making the sensors have difficulties in detecting small refractive index changes accurately. To address this problem, this paper proposes and demonstrates a low dimensional nanostructure (Au nanospheres, WS2) assisted LRSPR sensor to achieve an effective enhancement of the sensor interfaced electric field and thus improve the sensitivity. The performance parameters of the two sensors are compared with the LRSPR sensor by finite element method analysis, and the results showed that the assistance of the low dimensional nanostructure has a positive effect on the sensor. The first refractive index sensing experiment of the WS2-assisted LRSPR sensor was realized with a 25.47% increase in sensitivity and a 7.13% increase in FOM simultaneously, and the Au nanospheres-assisted LRSPR sensor with a 29.23% increase in sensitivity and a 15.95% increase in FOM simultaneously. The introduction of low dimensional nanostructures provides a flexible and effective means of sensitization for LRSPR sensors, making the plasmon resonance sensors combine high sensitivity, narrow FWHM and high FOM, which have promising applications in biochemical sensing.

Low-power flexible organic memristor based on PEDOT:PSS/pentacene heterojunction for artificial synapse.

Organic synaptic memristors are of considerable interest owing to their attractive characteristics and potential applications to flexible neuromorphic electronics. In this work, an organic type-II heterojunction consisting of poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) and pentacene was adopted for low-voltage and flexible memristors. The conjugated polymer PEDOT:PSS serves as the flexible resistive switching (RS) layer, while the thin pentacene layer plays the role of barrier adjustment. This heterojunction enabled the memristor device to be triggered with low-energy RS operations (V < ± 1.0 V and I < 9.0 µA), and simultaneously providing high mechanical bending stability (bending radius of ≈2.5 mm, bending times = 1,000). Various synaptic properties have been successfully mimicked. Moreover, the memristors presented good potentiation/depression stability with a low cycle-to-cycle variation (CCV) of less than 8%. The artificial neural network consisting of this flexible memristor exhibited a high accuracy of 89.0% for the learning with MNIST data sets, even after 1,000 tests of 2.5% stress-strain. This study paves the way for developing low-power and flexible synaptic devices utilizing organic heterojunctions.

The Mechanism of Action of Nanomaterials Loaded with Clarithromycin after Sinusitis Surgery under the Guidance of Dynamic Enhanced Scanning.

This study was to explore the mechanism of action of nanomaterial-loaded clarithromycin (CLA) after sinusitis surgery. Under the guidance of dynamic enhanced scanning (DES). 120 patients with sinusitis admitted to the First Affiliated Hospital of China Medical University from July 2019 to March 2020 were selected and divided into a control group and an observation group according to the random number table method, with 60 cases in each group. Then, the CLA-containing nano-polylactic acid material was prepared, observed with the scanning electron microscope (SEM), and its drug release ability was tested. All patients underwent endoscopic sinus surgery under general anesthesia. After the surgery was completed, patients in the control group were given only CLA capsules, and patients in the observation group were given freshly prepared nanomaterial-loaded CLA, and both groups of patients were continuously observed for two weeks. After that, the patients were examined using the dynamic enhancement computed tomography (CT). The clinical efficacy, serum interleukin-4 (IL-4), interleukin-8 (IL-8), and tumor necrosis factor α (TNF-α) levels of the two groups of patients were observed. The secretions of the patients' sinuses were performed with microbial bacterial culture, and the results were observed and recorded. Results showed that the characterization and analysis of the nano drug-carrying preparation suggested that the polylactic acid nanomembrane showed linear fiber morphology, relatively dense distribution, not greatly different fiber diameter, and small porosity. Characterization under a field of view (FOV) of 500 um showed that the fiber surface was smooth and rich in content. The release of CLA showed a gradual and steady upward trend. On the 25th day, nearly 50% of the dose had been released, and it had reached more than 90% of the total release on the 55th day. According to the statistics on the clinical efficacy of patients, it was found that the number of cured and effective patients in the observation group was higher than that of the control group, while the number of ineffective cases was much lower than that of the control group. The dynamic enhanced CT examination results of the patients in the control group after treatment showed that the soft tissue mass on the posterior right side of the nasopharynx was reduced, but the pharyngeal suture still existed; while those in the observation group showed that the plain scan density was uniform, and the mastoid air cells were clear on both sides. The number of cases with Staphylococcus aureus (S. aureus), Staphylococcus saprophyticus (S. saprophyticus), and Pasteurella multocida infections in the observation group were observably lower than those of the control group (P< 0.05), and it was the same case for the levels of serum IL-4, IL-8, and TNF-α. Conclusion: after dynamic enhanced CT scanning, it can be found that the nanomaterial-loaded CLA increased the utilization rate of the drug, showing good clinical efficacy, and effectively improved the clinical symptoms of patients, achieving the therapeutic effect.

E2F4 transcription factor is a prognostic biomarker related to immune infiltration of head and neck squamous cell carcinoma.

To investigate the relationship between the transcription factor, E2F4, and head and neck squamous cell carcinoma (HNSCC), and to preliminarily explore the signaling pathways and immunological role of E2F4. The mRNA expression of E2F4 in HNSCC was evaluated by searching Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) datasets. E2F4 protein expression was analyzed by immunohistochemistry using the CMU1h-ENT database. The association between E2F4 expression and tumor infiltration of immune cells was analyzed. Intracellular signaling by E2F4 was explored using KEGG and GO analysis. The correlation of E2F4 expression with clinical characteristics and its prognostic role were validated and analyzed in TCGA database. From the analysis of GEO and TCGA data, E2F4 expression was found to be up-regulated in HNSCC tumor tissues, and its level was associated with T, Grade, and M staging. Kaplan-Meier curve and Cox analyses indicated that the high expression of E2F4 was related to a poor prognosis. Thus, E2F4 was considered a potential prognostic factor for HNSCC. Immunohistochemical staining showed that E2F4 was mainly localized in the cell nucleus; it was highly expressed in HNSCC tissues, with a significant difference noted from that in pericancerous mucosa tissues. A correlation was observed between the differential expression of E2F4 and the immune infiltration of HNSCC. As revealed by KEGG and GO analysis, differential enrichment was found in the cell cycle, spliceosome, meiosis, microbial polysaccharide synthesis, and WNT signaling pathway, as well as in cyclic adenosine monophosphate, ERBB2, VEGF, GCNP and MYC pathways. E2F4 plays an important role in tumor progression and may be a critical biological prognostic factor for HNSCC. In addition, it functions in the nucleus as a transcription factor, regulates immune cells, and could be a promising molecular target for the diagnosis and treatment of HNSCC.

Research advances on surface plasmon resonance biosensors.

The surface plasmon resonance (SPR) phenomenon is of wide interest due to its sensitivity to changes in surface refractive index for the label-free, highly sensitive and rapid detection of biomarkers. This paper reviews research progress on SPR biosensors modified with different substrate structures and surface materials, surface plasmon resonance imaging (SPRI), and SPR-enhanced electrochemiluminescent (ECL) biosensors for applications in biosensing in the last five years. This paper focuses on the research on the application of the SPR phenomenon in the field of bio-detection, reviews the sensing characteristics of SPR biosensors with substrate structures of prisms, gratings, and optical fibers, and summarizes and analyzes the sensitivity and interference resistance of SPR sensors with surface modification of different materials (high-refractive index dielectric films, metallic micro- and nanostructures, and surface antifouling materials). Considering that imaging is an important tool for biomedical detection, this paper reviews the research progress on SPRI technology in the field of biomedical detection. In addition, this paper also reviews the research progress on SPR-enhanced ECL biosensors in the field of biosensing. Finally, this paper provides an outlook on the development trends of biosensing technology in terms of portable high-precision SPR sensors, reduction of self-loss of thin film materials, optimization of image processing techniques and simplification of electrode modification for ECL sensors.

Fbxw7 and Skp2 Regulate Stem Cell Switch between Quiescence and Mitotic Division in Lung Adenocarcinoma.

BACKGROUND/AIMS: The molecular mechanism of dormancy initiation of cancer stem cells (CSCs) is not clear. This study was to explore the molecular mechanism by which CSCs switch from mitotic division to quiescence. METHODS: MTT assays, flow cytometry, Western blotting, qRT-PCR, and immunofluorescence staining were used to test cell viability, cell cycle and expression of F-box and WD repeat domain-containing 7 (Fbxw7), c-myc, S phase kinase associated protein-2 (Skp2), cyclin-dependent kinase inhibitor 1B (p27), octamer-binding transcription factor 3/4 (Oct3/4), and ß catenin gene in 5-fluorouracil (5-FU)-treated A549 cells. Lung adenocarcinoma xenograft models were employed to detect the effects of Fbxw7 on tumor growth. RESULTS: 5-FU inhibited the proliferation of A549 cells, with a median inhibitory concentration (IC50) of 200 µg/ml after 24 h treatment. 5-FU treatment increased the expressions of Oct3/4, Fbxw7, and p27 and increased the number of A549 cells at G0/G1. 5-FU treatment triggered nuclear translocation of ß-catenin, decreased the expression levels of c-myc and Skp2, and decreased the number of A549 cells at S phase. Release from 5-FU decreased the expressions of Oct3/4, Fbxw7 and p27; decreased the percentage of cells in the G0/G1 phase; increased the expressions of Skp2 and c-myc; and increased the proportion of cells in S phase. 5-FU treatment led to high expressions of Oct3/4, c-myc, and p27, with low expressions of Fbxw7 and Skp2. Knockdown of Fbxw7 augmented the expression of c-myc and decreased the proportion of A549 cells in Go/G1 phase. Skp2 siRNA increased the expression of p27 and the percentage of G0/G1 phase cells and reduced the proportion of S phase cells. Fbxw7 overexpression inhibited tumor growth in mouse lung adenocarcinoma xenograft models. When Fbxw7 expression was low, Skp2 expression was higher in lung adenocarcinoma tissues and associated with the differentiation of lung adenocarcinoma. CONCLUSION: 5-FU enriches the CSCs in lung adenocarcinoma cells via increasing Fbxw7 and decreasing Skp2 expression, followed by downregulation of c-myc and upregulation of p27, which switches cells to quiescence.

Changes in the methylation status of the Oct3/4, Nanog, and Sox2 promoters in stem cells during regeneration of rat tracheal epithelium after injury.

We investigated the relationship between promoter methylation and tracheal stem cell activation. We developed a model of rat tracheal epithelium regeneration after 5-fluorouracil (5-FU)-induced injury. Using immunohistochemistry and Western blotting, the expression levels of the stem cell pluripotency regulator Oct3/4 and differentiation marker CK14 were measured after 5-FU treatment. The methylation status of the Oct3/4, Nanog, and Sox2 promoters was investigated using methylation-specific PCR. Additionally, the effects of 5-azacytidine (5-azaC), a demethylating agent, on Oct3/4, Nanog, and Sox2 mRNA and protein expression were evaluated. Finally, we measured the activity of the maintenance and de novo DNA methyltransferases DNMT1, DNMT3a, and DNMT3b. Our data indicate that Oct3/4, Sox2, and Nanog are transiently expressed in response to 5-FU-induced injury, and then they are gradually silenced as the cells differentiate. DNA methylation can result in silencing of gene expression, and it can determine whether tracheal stem cells are in an active or dormant state. Treatment with 5-FU reversed the methylation of the Oct3/4, Nanog, and Sox2 promoters, which corresponded to increases in Oct3/4, Nanog, and Sox2 mRNA and protein. Thus, both maintenance and de novo methyltransferases are involved in regulating tracheal stem cell dormancy and activation.