Anti cancer molecular mechanism of Actinidia chinensis Planch in gastric cancer based on network pharmacology and molecular docking

Purpose: To determine the anti-tumor effects of Actinidia chinensis Planch (ACP) root extract as well as its mechanism of action against gastric cancer (GC) using network pharmacology.Methods: The bioactive compounds and targets of ACP, as well as GC-related genes were identified from a series of public databases. Functional enrichment analysis was conducted to find relevant biological processes and pathways. The survival analysis was conducted using GEPIA tool. Autodock was used to carry out molecular docking between the ingredients and their targets.Results: A total of 20 bioactive compounds with 209 corresponding targets were identified for ACP, and a total of 871 GC-related genes were obtained. Forty-nine (49) targets of ACP were identified as candidate genes for the prevention of GC, and the PPI network with 584 interactions among these genes was constructed. The data demonstrated that the candidate targets were involved in multiple biological processes such as oxidative stress response, apoptosis, and proliferation. Moreover, these candidate targets were significantly associated with cancer-related pathways and signal transduction pathways. The compound-target-pathway network containing 16 bioactive compounds, 49 targets and 10 pathways was constructed and visualized, and the top 3 targets with a higher degree value were AKT1, MYC, and JUN, respectively. Survival analysis revealed significant associations between GC prognosis and several targets (PREP, PTGS1, AR, and PTGS2). Molecular docking further revealed good binding affinities between bioactive compounds and the prognosis-related targets, indicating the potential roles of these ingredient-target interactions in GC protection.Conclusion: Taken together, this study has provided novel clues for the determination of the antigastric cancer mechanism of ACP

Photoelectrochemical and electrochemical ratiometric aptasensing: a case study of streptomycin

There has been much interest in constructing ratiometric sensors using different sensing techniques because of their synergistic effect, although the simultaneous collection of the signals is challenging. Herein, we propose a ratiometric aptasensing strategy based on the dual-detection model with a photoelectrochemical (PEC) “signalon” and an electrochemical (EC) “signal-off”. As a proof-of-concept study, CdTe quantum dots (CdTe QDs) and a methylene blue-labeled aptamer (MB-Apt) were used to generate PEC and EC signals in the sensing system. The target-induced conformational change of MB-Apt pushed MB away from the electrode, thereby decreasing the EC signal; at the same time, the reduced steric hindrance favored the restoration of the PEC signal from the CdTe QDs. Thus, this PEC-EC strategy can achieve the PEC “signal-on” and EC “signal-off” states simultaneously, as well as allowing quantitative analysis of the target based on the ratio of the current intensities. As a model application, an aptasensor fabricated for streptomycin detection showed a wide linear range from 0.03 to 100 μM with a detection limit of 10 nM (S/N = 3). The proposed sensing platform displayed superior analytical properties compared with methods based on PEC or EC alone. Our work provides an efficient dual-detection modelbased ratiometric strategy for advanced analysis, and paves the way to the simultaneous acquisition of signals

Mesoporous WO3 Nanofibers With Crystalline Framework for High-Performance Acetone Sensing

Semiconducting metal oxides with abundant active sites are regarded as promising candidates for environmental monitoring and breath analysis because of their excellent gas sensing performance and stability. Herein, mesoporous WO3 nanofibers with a crystalline framework and uniform pore size is successfully synthesized in an aqueous phase using an electrospinning method, with ammonium metatungstate as the tungsten sources, and SiO2 nanoparticles and polyvinylpyrrolidone as the sacrificial templates. The obtained mesoporous WO3 nanofibers exhibit a controllable pore size of 26.3–42.2 nm, specific surface area of 24.1–34.4 m2g−1, and a pore volume of 0.15–0.24 cm3g−1. This unique hierarchical structure, with uniform mesopores and interconnected channels, could facilitate the diffusion and transportation of gas molecules in the framework. Gas sensors, based on mesoporous WO3 nanofibers, exhibit an excellent performance in acetone sensing with a low limit of detection (<1 ppm), short response-recovery time (24 s/27 s), a linear relationship in a broad range, and good selectivity

Activation of Toll-Like Receptor 3 Impairs the Dengue Virus Serotype 2 Replication through Induction of IFN-β in Cultured Hepatoma Cells

Toll-like receptors (TLRs) play an important role in innate immunity against invading pathogens. Although TLR signaling has been indicated to protect cells from infection of several viruses, the role of TLRs in Dengue virus (DENV) replication is still unclear. In the present study, we examined the replication of DENV serotype 2 (DENV2) by challenging hepatoma cells HepG2 with different TLR ligands. Activation of TLR3 showed an antiviral effect, while pretreatment of other TLR ligands (including TLR1/2, TLR2/6, TLR4, TLR5 or TLR7/8) did not show a significant effect. TLR3 ligand poly(I∶C) treatment prior to viral infection or simultaneously, but not post-treatment, significantly down-regulated virus replication. Pretreatment with poly(I∶C) reduced viral mRNA expression and viral staining positive cells, accompanying an induction of the type I interferon (IFN-β) and type III IFN (IL-28A/B). Intriguingly, neutralization of IFN-β alone successfully restored the poly(I∶C)-inhibited replication of DENV2. The poly(I∶C)-mediated effects, including IFN induction and DENV2 suppression, were significantly reversed by IKK inhibitor, further suggesting that IFN-β is the dominant factor involved in the poly(I∶C) mediated antiviral effect. Our study presented the first evidence to show that activation of TLR3 is effective in blocking DENV2 replication via IFN-β, providing an experimental clue that poly(I∶C) may be a promising immunomodulatory agent against DENV infection and might be applicable for clinical prevention

Fire Resistance of Reinforced Concrete T-Beams with Circular Web Openings

The flexural performances of a solid reinforced concrete (RC) T-beam and three RC T-beams with circular openings subjected to the ISO-834 standard fire were experimentally studied. The failure mode, fire resistance, time-deflection curve, and mid-span deflection recovery of the RC T-beams were analyzed by considering the factors such as the bottom chord depth and the stirrup status (refers to whether the stirrups were cut off when drilling). The results showed that the fire resistance of the RC T-beam with a 220 mm bottom chord was almost the same as that of the solid beam and both failed in ductile modes; however, the fire resistance of the RC T-beam with a 100 mm bottom chord was 18.9% lower than that of the solid beam and failed in a brittle mode. Whether the stirrups of the pure bending section were cut off when drilling had little effect on the fire resistance of the RC T-beam. Numerical simulations were also validated to study the mechanical properties influenced by the bottom chord depth. Finally, a simplified method of high precision was proposed to deduce flexural capacities of RC T-beams with circular openings under fire

A taxonomic revision of three Chinese spurless species of genus Epimedium L. (Berberidaceae)

Due to some common or similar features (e.g., small leaf, spurless, yellow flower), three Chinese species of the genus Epimedium (Berberidaceae), E. ecalcaratum, E. platypetalum, and E. campanulatum, are controversial based on morphological characteristics. In the present study, the descriptions of morphological characteristics for the three species were revised based on extensive studies and observations both in field and in herbaria. In general, E. ecalcaratum has long creeping rhizomes 1–3 mm in diameter, two alternate or opposite trifoliolate leaves, 7–14 flowers, and petals obovate and apex subacute. Epimedium platypetalum has short or long-creeping rhizomes 1–3 mm in diameter, one trifoliolate leaf, 2–6 flowers, and petals oblong and apex rounded. Epimedium campanulatum has compact rhizomes 4–6 mm in diameter, two alternate or opposite trifoliolate leaves, 15–43 flowers, and petals obovate and apex rounded. Through comparison, we found that despite the close affinity of these three species, they can be distinguished by rhizome differences, stem-leaves, the morphology of flower (e.g., petals), and the number of per inflorenscence

A ratiometry-induced successive reusable electrochemical aptasensing platform: efficient monitoring of aflatoxin B1 in peanut

Currently, most reusable aptasensors rely on the reassembly of aptamers to regenerate the sensing interface. However, it remains challenging to achieve successive aptasensor reusability. Herein, for the first time, we demonstrate that a ratiometric strategy endows the electrochemical aptasensor high reusability to realize the successive detection of aflatoxin B1 (AFB1). The model sensing interface used thionine (THI)-graphene nanocomposite and ferrocene (Fc)-labeled aptamer to output current signals (ITHI and IFc). For analysis, the specific recognition of AFB1 by aptamers caused it to strip from the electrode, and the value of ITHI/IFc varied linearly with AFB1 concentration over the 0.01-100 ng mL-1 range. This relationship also worked when using a single sensor for multiple successive testing but completely failed with ITHI or IFc alone. This unique successive reusability was ascribed to the ratiometric strategy capable of eliminating the environmental influence on both signals. The feasibility of the proposed aptasensor was validated by applying it to the successive detection of AFB1, which showed excellent accuracy and reliability compared with the official method, i.e., standard high-performance liquid chromatography-fluorescence (HPLC-FL). This successive reusable electrochemical aptasensing platform can be universal for advanced analysis, and it promotes the practical applications of aptasensors particularly in the field of rapid assays

Low-Frequency Vibrational Spectroscopy Characteristic of Pharmaceutical Carbamazepine Co-Crystals with Nicotinamide and Saccharin

The pharmaceutical co-crystal has attracted increasing interest due to the improvement of physicochemical properties of active pharmaceutical ingredients. The characterization of pharmaceutical co-crystal is an integral part of the pharmaceutical field. In this paper, the low-frequency vibrational properties for carbamazepine co-crystals with nicotinamide and saccharin (CBZ-NIC and CBZ-SAC) have been characterized by combining the THz spectroscopy with low-wavenumber Raman spectroscopy. The experiment results show that, compared with the individual constituents, CBZ-NIC and CBZ-SAC co-crystals not only have different characteristic absorption peaks in the 0.3-2.5 THz region, but also have significant low-wavenumber Raman characteristic peaks in 0–100 cm−1. Density functional theory was performed to simulate the terahertz and low-wavenumber Raman spectra of the two co-crystals, where the calculation agreed well with the measured vibrational peak positions. The vibrational modes of CBZ-NIC and CBZ-SAC co-crystals were assigned through comparing theoretical results with the experimental spectra. Meanwhile, the low-frequency infrared and/or Raman active of characteristic peaks for such co-crystals were discussed. The results indicate the combination of THz spectroscopy and low-wavenumber Raman spectroscopy can provide more comprehensive low-frequency vibrational information for pharmaceutical co-crystals, such as collective vibration and skeleton vibration, which could play an important role in pharmaceutical science

Sensitivity programmable ratiometric electrochemical aptasensor based on signal engineering for the detection of aflatoxin B1 in peanut

Accurately monitoring of aflatoxin B1 (AFB1), the most hazardous mycotoxin in agricultural products, is essential for the public health, but various testing demands (e.g. detection range, sensitivity) for different samples can be challenging for sensors. Here, we developed a sensitivity-programmable ratiometric electrochemical aptasensor for AFB1 analysis in peanut. Thionine functionalized reduced graphene oxide (THI-rGO) served as reference signal generator, ferrocene-labelled aptamer (Fc-apt) output the response signal. During analysis, the formation of Fc-apt-AFB1 complex led to its stripping from the electrode and faded the current intensity of Fc (IFc), while the current intensity of THI (ITHI) was enhanced. And ratiometric detection of AFB1 was achieved by using the current intensity ratio (ITHI/IFc) as quantitative signal. Compared with ratiometric strategies that highly rely on the labelled aptamers, the proposed strategy could regulate the value of ITHI/IFc by changing the modification of Fc-apt. And the detection sensitivity was found to be closely related to ITHI/IFc. Under the optimal conditions, the fabricated aptasensor with a dynamic range from 0.05–20 ng mL−1 and a detection limit of 0.016 ng mL−1 for AFB1 analysis. Besides, it exhibited excellent selectivity, reliability and reproducibility. The proposed sensitivity-programmable biosensor can be applied to detect various aptamer-recognized mycotoxins in agricultural sensing