Improved Adenoma Detection Rate Using a Novel Colonoscopic Distal Attachment: A Multicenter Randomized Controlled Trial.

INTRODUCTION: To evaluate the effect of Embrella, a novel-designed colonoscopic distal attachment, on adenoma detection rate (ADR) and adenoma per colonoscopy (APC), compared with standard colonoscopy in routine practice. METHODS: All consecutive participants who underwent routine colonoscopic examinations at 3 endoscopy centers in China were enrolled. Participants were randomly assigned in a 1:1 ratio to the Embrella-assisted colonoscopy (EAC) or standard colonoscopy (SC) groups. ADR, APC, inspection time, pain scores, and adverse events were recorded. RESULTS: Overall, 1,179 participants were randomized into the EAC (n = 593) and SC groups (n = 586). EAC increased the overall ADR from 24.6% to 34.2% ( P < 0.001) and improved APC from 0.44 to 0.64 ( P = 0.002). Subgroup analyses indicated that EAC significantly improved ADR for adenomas < 10 mm (13.8% vs 8.5%, P = 0.004 for 5-9 mm and 27.0% vs 17.2%, P < 0.001 for < 5 mm), nonpedunculated adenomas (26.6% vs 18.8%, P < 0.001), and adenomas in the transverse (10.8% vs 6.1%, P = 0.004) and left colon (21.6% vs 13.7%, P < 0.001). APC in the subgroup analyses was consistent with ADR. The mean inspection time was shorter with EAC (6.52 vs 6.68 minutes, P = 0.046), with no significant impact on participants' pain scores ( P = 0.377). Moreover, no EAC-related adverse events occurred. DISCUSSION: EAC significantly increased ADR and APC compared with SC, particularly for adenomas <10 mm, nonpedunculated adenomas, and adenomas in the transverse and left colon.

Heat accumulation and phase transition induction in a VO2 thin film by a femtosecond pulse-periodic radiation.

The kinetics of optical switching due to the insulator-metal phase transition in a VO2 thin film is studied experimentally at different laser pulse repetition frequencies (PRFs) in the NIR range and compared with temperature kinetics obtained through the thermal conductance calculations. Two switching processes have been found with characteristic times <2 ms and <15 ms depending on the PRF; the former is explained by the accumulation of metallic domains remaining after a single-pulse phase transition, and the latter is referred to the heat accumulation in the film. Consequently, the dynamics of the microscopic domains is leading in the initiation of phase transition under pulse-periodic conditions compared to the macroscopic heat transfer. The reverse transition at the radiation turn-off depends on the PRF with a time coefficient of 17.5 µs/kHz and is determined by the metallic domains' decay in the film. The results are important for understanding the nature of the insulator-metal transition in thin films of VO2 as well as using them in all-optical switches of pulse-periodic laser radiation.

Identification of triangular single crystals of transition metal dichalcogenides based on the detection algorithm.

The distinctive properties and facile integration of 2D materials hold the potential to offer promising avenues for the on-chip photonic devices, and the expeditious and nondestructive identification and localization of diverse fundamental building blocks become key prerequisites. Here, we present a methodology grounded in digital image processing and deep learning, which effectively achieves the detection and precise localization of four monolayer-thick triangular single crystals of transition metal dichalcogenides with the mean average precision above 90%, and the approach demonstrates robust recognition capabilities across varied imaging conditions encompassing both white light and monochromatic light. This stands poised to serve as a potent data-driven tool enhancing the characterizing efficiency and holds the potential to expedite research initiatives and applications founded on the utilization of 2D materials.

Clinicopathologic and endoscopic characteristics of ten patients with gastric hamartomatous inverted polyp: a single center case series.

BACKGROUND: Gastric hamartomatous inverted polyps (GHIPs) are not well characterized and remain diagnostically challenging due to rarity. Therefore, this study aims to investigate the clinicopathologic and endoscopic characteristics of patients with GHIP. METHODS: We retrospectively reviewed clinicopathologic and endoscopic features of ten patients with GHIP who were admitted to Beijing Friendship Hospital from March 2013 to July 2022. All patients were treated successfully by endoscopic resection. RESULTS: GHIPs were usually asymptomatic and found incidentally during gastroscopic examination. They may be sessile or pedunculated, with diffuse or local surface redness or erosion. On endoscopic ultrasonography, the sessile submucosal tumor-type GHIP demonstrated a heterogeneous lesion with cystic areas in the third layer of the gastric wall. Histologically, GHIPs were characterized by a submucosal inverted proliferation of cystically dilated hyperplastic gastric glands accompanied by a branching proliferation of smooth muscle bundles. Inflammatory cells infiltration was observed in the stroma, whereas only one patient was complicated with glandular low-grade dysplasia. Assessment of the surrounding mucosa demonstrated that six patients (60%) had atrophic gastritis or Helicobacter pylori-associated gastritis, and four patients (40%) had non-specific gastritis. Endoscopic resection was safe and effective. CONCLUSIONS: GHIPs often arise from the background of abnormal mucosa, such as atrophic or H.pylori-associated gastritis. We make the hypothesis that acquired inflammation might lead to the development of GHIPs. We recommend to make a full assessment of the background mucosa and H. pylori infection status for evaluation of underlying gastric mucosal abnormalities, which may be the preneoplastic condition of the stomach.

Nonlinear optical response and ultrafast all-optical modulation of Nb4C3.

MXenes exhibit a variety of unique electronic, optical, chemical, and mechanical properties. In this work, the nonlinear optical (NLO) properties of Nb4C3Tx are systematically investigated. The Nb4C3Tx nanosheets exhibit saturable absorption (SA) response from visible region to near-infrared region and better saturability under 6 ns pulse excitation than that under 380 fs excitation. The ultrafast carrier dynamics show a relaxation time of ∼6 ps, which suggests a high optical modulation speed of ∼160 GHz. Consequently, an all-optical modulator is demonstrated by transferring the Nb4C3Tx nanosheets to the microfiber. The signal light can be modulated well by pump pulses with a modulation rate of 5 MHz and an energy consumption of 12.564 nJ. Our study indicates that Nb4C3Tx is a potential material for nonlinear devices.

Nonlinear optical properties and ultrafast carrier dynamics of ultrathin ReSe2.

Rhenium diselenide (ReSe2) has shown great application potential in the field of optical devices because of its excellent optoelectronic properties. In this study, we systematically investigated the nonlinear optical absorption properties of mono- and bi-layer ReSe2 and the ultrafast carrier dynamics process in the ultraviolet to near-infrared spectral range as the essential foundational groundwork for harnessing the potential of ultrathin ReSe2-based optoelectronic devices. We found that ReSe2 has excellent nonlinear absorption performance and a low saturation absorption intensity that is better than that of many semiconductor materials. Meanwhile, pump-probe and transient absorption technology revealed the underlying dynamic mechanisms, including bandgap renormalization and Auger recombination. This study can broaden the horizons of material science and propel the development of different applications of ReSe2.

Microscopic optical nonlinearities and transient carrier dynamics in indium selenide nanosheet.

This work systematically investigates the third-order nonlinear optical (NLO) properties and ultrafast carrier dynamics of layered indium selenide (InSe) obtained by mechanical exfoliation (ME). The two-photon absorption (TPA) effect of layered InSe was tested using micro-Z/I-scan techniques. The results indicate that InSe flakes undergo the TPA response under the excitation of both 520 nm and 1040 nm fs pulses, and that InSe is more likely to achieve TPA saturation under visible light excitation. Furthermore, ultrafast carrier dynamics revealed that InSe flakes in the visible region undergo a transition from photoinduced absorption to photobleaching and exhibit a fast recombination time of ∼0.4-1ps, suggesting a high optical modulation speed as high as ∼1-2.5 THz.

Femtosecond laser-induced phase transition in VO2 films.

VO2 is a very promising material due to its semiconductor-metal phase transition, however, the research on fs laser-induced phase transition is still very controversial, which greatly limits its development in ultrafast optics. In this work, the fs laser-induced changes in the optical properties of VO2 films were studied with a variable-temperature Z-scan. At room temperature, VO2 consistently maintained nonlinear absorption properties at laser repetition frequencies below 10 kHz while laser-induced phase transition properties appeared at higher repetition frequencies. It was found by temperature variation experiments at 100 kHz that the modulation depth of the laser-induced VO2 phase transition was consistent with that of the ambient temperature-induced phase transition, which was increased linearly with thickness, further confirming that the phase transition was caused by the accumulation of thermal effects of a high-repetition-frequency laser. The phase transition process is reversible and causes substantial changes in optical properties of the film, which holds significant promise for all-optical switches and related applications.

Nonlinear absorption and integrated photonics applications of MoSSe.

This study explores the wavelength-dependent and pulse-width-dependent nonlinear optical properties of liquid-phase exfoliated molybdenum sulfide selenide (MoSSe) nanosheets. The saturable absorption response of MoSSe nanosheets in the visible region is better than that in the near-infrared region, and the response under 6-ns pulse excitation is better than that of a 380-fs pulse. Furthermore, based on the first-principles calculations, we designed a phase modulator and optimized its structure by integrating a monolayer MoSSe into a silicon slot waveguide. The simulation results revealed that the phase shift could achieve a high optical extinction. Consequently, MoSSe exhibits satisfactory nonlinear optical properties and an excellent potential for applications in optoelectronic devices.

Sensitive detection of T790M mutations in lung cancer biopsies using a PCR-based lateral flow assay.

T790 M point mutations in EGFR exon 20 are regarded as the most common cause of resistance to epidermal growth factor receptor tyrosine kinase inhibitor treatment. In this study, a PCR-based lateral flow assay (PCR-LFA) was developed to detect T790 M mutations in human genomic DNA. Detection sensitivity was determined using DNA at different mutant to wild-type ratios. The limit of detection of mutant alleles was 15 copies per reaction. The sensitivity of detection of these mutations in 40 formalin-fixed paraffin-embedded tissue biopsies from non-small cell lung cancer patients was analyzed using PCR-LFA and amplification refractory mutation system (ARMS) PCR. Our assay provided the same information as ARMS PCR for 95% (38/40) of the samples. T790 M mutations were detected in 15 (37.5%) and 13 samples using our assay and ARMS PCR, respectively. Droplet digital PCR confirmed the presence of T790 M mutations in the two discordant samples. These results indicate that PCR-LFA is more sensitive than ARMS PCR for clinical screening of these mutations.

Anisotropic Raman scattering and intense broadband second-harmonic generation in tellurium nanosheets.

Tellurium (Te) is a novel elementary material, which has recently attracted extensive attention due to its intriguing physical properties, such as topological, thermoelectric, and photoelectric properties. Further study on Te crystal structures will help to understand its properties and facilitate its application. Here, the angle-resolved polarized Raman spectroscopy has been employed to study Te crystal symmetry. Three different Raman vibration modes were obtained, each of which possess a different polarization dependence. Furthermore, it is revealed that Te nanosheets show a second-order harmonic response over a wide spectrum and have the greatest conversion efficiency at an excitation wavelength of 880 nm. Its second-order nonlinear susceptibility is estimated to be 2049pmV-1. This substantial nonlinear optical response endows Te nanosheets with the potential for developing nonlinear photonic and optoelectronic nanodevices with high efficiency.

Titanium Carbide MXenes Mediated In Situ Reduction Allows Label-Free and Visualized Nanoplasmonic Sensing of Silver Ions.

The label-free assay has drawn extensive attention because it does not require a labeling step and enables direct interaction and signal transduction between the sensing unit and target analytes. Herein, we demonstrate a proof-of-principle concept of a label-free and visualized nanoplasmonic strategy for silver ions sensing, where only Ti3C2 MXenes are employed by exploring their excellent adsorption affinity and reductive property toward metal ions. Ag+ was adsorbed onto the surface of Ti3C2 MXene nanosheets, followed by the Ti3C2 MXenes mediated in situ silver nanoparticles (Ag NPs) generation without adding any extra stabilizing or reducing agent. The excellent localized surface plasmon resonances at a particular wavelength provide Ag NPs the capability for colorimetric assay with a detection limit of 0.615 µM. With the assistance of a smartphone, RGB analysis exhibited visualized results consistent with the results measured on a UV-vis spectrometer, promising a budget, simple-operating on-site detection. Moreover, the detection of Ag+ in real samples was achieved with satisfactory results meeting the analysis demand for the Drinking Water Standards of the World Health Organization (WHO) and the United States Environmental Protection Agency (U.S. EPA). These results reveal that Ti3C2 MXenes possess great potential in building convenient label-free colorimetry nanoplatforms and may evoke more inspirations to explore strategies for the direct sensing of analytes.

A Novel Hierarchical Nanostructure for Enhanced Optical Nonlinearity Based on Scattering Mechanism.

Surface modification of nonlinear optical materials (NOMs) is widely applied to fabricate diverse photonic devices, such as frequency combs, modulators, and all-optical switches. In this work, a double-layer nanostructure with heterogeneous nanoparticles (NPs) is proposed to achieve enhanced third-order optical nonlinearity of NOMs. The mechanism of modified optical nonlinearity is elucidated to be the scattering-induced energy transfer between adjacent NPs layers. Based on the LiNbO3 platform, as a typical example, double layers of embedded Cu and Ag NPs are synthesized by sequential ion implantation, demonstrating twofold magnitude of near-infrared enhancement factor and modulation depth in comparison with a single layer of Cu NPs. With the elastic collision model and thermolysis theory being considered, the shift of the localized surface plasmon resonance (LSPR) peak reveals the formation mechanism of the double-layer nanostructure. Utilizing the enhanced optical nonlinearity of LiNbO3 as modulators, a Q-switched mode-locked waveguide laser at 1 µm is achieved with shorter pulse duration. It suggests potential applications to improve the performance of nonlinear photonic devices by using double-layer metallic nanostructures.

RN181 is a tumour suppressor in gastric cancer by regulation of the ERK/MAPK-cyclin D1/CDK4 pathway.

RN181, a RING finger domain-containing protein, is an E3 ubiquitin ligase. However, its biological function and clinical significance in cancer biology are obscure. Here, we report that RN181 expression is significantly down-regulated in 165 tumour tissues of gastric carcinoma (GC) versus adjacent non-tumour tissues, and inversely associated with tumour differentiation, tumour size, clinical stage, and patient's overall survival. Alterations of RN181 expression in GC cells by retrovirus-transduced up-regulation and down-regulation demonstrated that RN181 functions as a tumour suppressor to inhibit growth of GC in both in vitro culture and in vivo animal models by decreasing tumour cell proliferation and increasing tumour cell apoptosis. Cell cycle analysis revealed that RN181 controls the cell cycle transition from G1 to S phase. Mechanistic studies demonstrated that RN181 inhibits ERK/MAPK signalling, thereby regulating the activity of cyclin D1-CDK4, and consequently controlling progression in the cell cycle from G1 to S phase. Restoring CDK4 in GC cells rescued the inhibitory phenotype produced by RN181 in vitro and in vivo, suggesting a dominant role of CDK4 in control of the tumour growth by RN181. Importantly, RN181 expression is inversely correlated with the expression of cyclin D1 and CDK4 in GC clinical samples, substantiating the role of the RN181-cyclin D1/CDK4 pathway in control of the tumour growth of GC. Our results provide new insights into the pathogenesis and development of GC and rationale for developing novel intervention strategies against GC by disruption of ERK/MAPK-cyclin D1/CDK4 signalling. In addition, RN181 may serve as a novel biomarker for predicting clinical outcome of GC. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

p,p'-Dichlorodiphenyltrichloroethane promotes aerobic glycolysis via reactive oxygen species-mediated extracellular signal-regulated kinase/M2 isoform of pyruvate kinase (PKM2) signaling in colorectal cancer cells.

Aerobic glycolysis is crucial to tumor cells to acquire energy for proliferation and metastasis. Dichlorodiphenyltrichloroethane (DDT), which is a persistent organic pollutant, has been associated with colorectal cancer (CRC) progressions, but the influence of p,p'-DDT on CRC cell metabolism remains unclear. This study showed that exposure to low concentrations of p,p'-DDT from 10-11 to 10-7 M for 48 hours significantly increased glucose uptake and lactate production in colorectal adenocarcinoma cells, which were accompanied by the upregulation of proteins associated with aerobic glycolysis including glucose transporter1, lactate dehydrogenase A, and PDH kinase. We found p,p'-DDT elevated the expression and nucleus translocation of M2 isoform of pyruvate kinase (PKM2), which was responsible for p,p'-DDT-induced enhancement of aerobic glycolysis. Moreover, extracellular signal-regulated kinase (ERK1/2) activation by p,p'-DDT modulated the impacts of p,p'-DDT on PKM2 and aerobic glycolysis. Treatment of p,p'-DDT increased intracellular reactive oxygen species (ROS). N-acetyl-L-cysteine, an ROS inhibitor, prevented p,p'-DDT-induced promotion of aerobic glycolysis, ERK1/2 activation, upregulation, and nucleus translocation of PKM2. Taken together, these results demonstrated that p,p'-DDT promotes aerobic glycolysis via ROS-mediated ERK/PKM2 signaling.

M2 macrophages mediate sorafenib resistance by secreting HGF in a feed-forward manner in hepatocellular carcinoma.

BACKGROUND: Sorafenib is the only approved first line systemic therapy for advanced hepatocellular carcinoma (HCC) in the last decade. Tumour resistance to sorafenib has been of major obstacles to improve HCC patient survival. METHODS: We polarised THP-1 cells to M1 and M2 macrophages, performed various in vitro assays and developed sorafenib-resistant xenograft models to investigate the role of tumour-associated macrophages (TAM)-secreted molecules in HCC resistance to the targeted therapy. RESULTS: We demonstrated M2, but not M1, macrophages not only promote proliferation, colony formation and migration of hepatoma cells but also significantly confer tumour resistance to sorafenib via sustaining tumour growth and metastasis by secreting hepatocyte growth factor (HGF). HGF activates HGF/c-Met, ERK1/2/MAPK and PI3K/AKT pathways in tumour cells. Tumour-associated M2 macrophages were accumulated in sorafenib-resistance tumours more than in sorafenib-sensitive tumours in vivo and produced abundant HGF. HGF chemoattracts more macrophages migrated from surrounding area, regulates the distribution of M2 macrophages and increases hepatoma resistance to sorafenib in a feed-forward manner. CONCLUSIONS: Our results provide new insights into the mechanisms of sorafenib resistance in HCC and rationale for developing new trials by combining sorafenib with a potent HGF inhibitor such as cabozantinib to improve the first line systemic therapeutic efficacy.

8.8 GHz Q-switched mode-locked waveguide lasers modulated by PtSe2 saturable absorber.

We demonstrate high-repetition-rate fundamentally Q-switched mode-locked Nd:YAG waveguide laser modulated by platinum diselenide (PtSe2) saturable absorber. The laser operation platform is a femtosecond laser-written monolithic Nd:YAG waveguide, and the saturable absorber is large-area few-layer PtSe2 that possesses relatively lower saturation intensity and higher modulation depth in comparison with graphene. With the superb ultrafast nonlinear saturable absorption properties of as-synthesized PtSe2, the waveguide laser could operate at ~8.8 GHz repetition rate and ~27 ps pulse duration, while maintaining a relatively high slope efficiency of 26% and high stability with signal-to-noise ratio (SNR) up to 54 dB. Our work indicates the promising applications of laser-written Nd:YAG waveguides and atomically thin PtSe2 for on-chip integration of GHz laser sources toward higher repetition rates and shorter pulse duration.

Enhanced two-photon absorption and two-photon luminescence in monolayer MoS2 and WS2 by defect repairing.

In this work, we investigated the nonlinear optical properties of monolayer MoS2 and WS2 modulated by defect engineering via chemical treatment. The results demonstrate that the two-photon luminescence (TPL) and two-photon absorption (TPA) coefficient were remarkably improved after the repair of sulfur vacancies for both monolayer MoS2 and WS2. After the chemical treatment, the nonradiative relaxation path dominant in pristine monolayer MoS2 is significantly alleviated, resulting in enhanced TPL. Our work affords an effective way to tailor the nonlinear absorption, luminescence and relaxation properties of sulfur-based two-dimensional metal dichalcogenides by defect engineering.

Photonic-crystal-based broadband graphene saturable absorber.

The enhanced saturable absorption (SA) of a one-dimensional (1D) photonic crystal (PC) made from polymers and graphene composites by spin coating is observed. It shows obvious bandgaps at two wavelengths in transmittance. Femtosecond Z-scan measurement at 515 nm and 1030 nm reveals a distinct enhancement in the effective nonlinear absorption coefficient ßeff for graphene nanoflakes embedded in the PC, when compared with the bulk graphene-polymer composite. The effect is studied in a wide range of laser intensities. Graphene inclusion into a 1D PC remarkably decreases the SA threshold and saturation intensity, providing a desired solution for an advanced all-optical laser mode-locking device.

Plasmonic Ag nanoparticles embedded in lithium tantalate crystal for ultrafast laser generation.

We report the Ag nanoparticles (NPs) embedded in LiTaO3 (AgNP:LT) by direct Ag+ ion implantation. Transmission electron microscope imaging indicates that the embedded Ag NPs have an average diameter of 3.65 nm. The linear optical absorption spectrum of AgNP:LT peaking at 477 nm is observed owing to the typical effect of localized surface plasmon resonance. Z-scan investigation shows ultrafast saturable absorption of AgNP:LT at the near infrared 1 µm wavelength, which enables AgNP:LT to be a new saturable absorber (SA) for the generation of 1 µm Q-switched mode-locked pulsed laser with pulse duration of 35 ps and repetition rate of 8.74 GHz. This work not only opens a new way to tailor the nonlinearity of LiTaO3 by embedding Ag+ NPs, but also develops AgNP:LT as a new SA for ultrafast laser generation.