[Establishment and Effective Evaluation of Haikou Ozone Concentration Statistical Prediction Model].

This study selected 15 key predictors of the maximum of 8-hour averaged ozone (O3) concentration (O3-8h), using the O3 concentration of Haikou and ERA5 reanalysis data from 2015 to 2020, and constructed a multiple linear regression (MLR) model, support vector machine (SVM) model, and BP neural network (BPNN) model, to predict and test the O3-8h concentration of Haikou in 2021. The results showed that the absolute value of correlation coefficients between the O3-8h and related key prediction factors was mainly among 0.2 and 0.507. The 1 000 hPa relative humidity (RH1000), wind direction (WD1000), and 875 hPa meridional wind (v875) showed a good indicative effect on the O3-8h, with the absolute correlation value exceeding 0.4. The three prediction models could predict the seasonal variation in the O3-8h in Haikou, which was larger in the winter half year and smaller in the summer half year. The root mean square error(RMSE) was the smallest (22.29 µg·m-3) in the BPNN model. The correlation coefficients between the predicted values of three statistical models and observations were ranked as 0.733 (BPNN) > 0.724 (SVM) > 0.591 (MLR), all passing the 99.9% significance test. For the prediction of the O3-8h level, we found that TS scores of these three prediction models decreased with the increase in O3-8h concentration level. Relatively, the point over rate and not hit rate increased with the rise in O3-8h concentration level. TS scores of the SVM and BPNN model were relatively larger than those of MLR, especially in the light pollution level with TS scores remaining above 70%, indicating a better prediction capability.

The active ingredients in Chinese peony pods synergize with antibiotics to inhibit MRSA growth and biofilm formation.

Staphylococcus aureus (S. aureus) is a zoonotic pathogen that infects both humans and animals. The rapid spread of methicillin-resistant S. aureus (MRSA) and its resistance to antibiotics, along with its ability to form biofilms, poses a serious challenge to the clinical application of traditional antibiotics. Peony (Paeonia lactiflora Pall.) is a traditional Chinese medicine with multiple pharmacological effects. This study observed the strong antibacterial and antibiofilm activity of the water extract (WE) and ethyl acetate extract (EA) of Chinese peony pods against MRSA. The combination of EA and vancomycin, cefotaxime, penicillin G or methicillin showed a synergistic or additive antibacterial and antibiofilm effects on MRSA, which is closely related to the interaction of 1,2,3,4,6-penta-O-galloyl-ß-D-glucose (PG) and methyl gallate (MG). The active ingredients in peony pods have been found to increase the sensitivity of MRSA to antibiotics and demonstrate antibiofilm activity, which is mainly related to the down-regulation of global regulatory factors sarA and sigB, extracellular PIA and eDNA encoding genes icaA and cdiA, quorum sensing related genes agrA, luxS, rnaIII, hld, biofilm virulence genes psma and sspA, and genes encoding clotting factors coa and vwb, but is not related to genes that inhibit cell wall anchoring. In vivo test showed that both WE and EA were non-toxic and significantly prolonged the lifespan of G. mellonella larvae infected with MRSA. This study provides a theoretical basis for further exploration of the combined use of PG, MG and antibiotics to combat MRSA infections.

In situ, synthesis of chitosan fabricated tellurium nanoparticles for improved antimicrobial and anticancer applications.

The emergence of antibiotic resistance has had a severe impact on human health and economic burdens, drawing attention to the development of novel antimicrobial therapies. Polymer-metal composites have shown evidence of therapeutic applications by exerting antimicrobial effects and delivering these antimicrobials with biocompatibility. Therefore, this study prepared and characterized chitosan (CS)-fabricated tellurium nanoparticles (Te NPs) for enhanced antimicrobial, antioxidant, and cytotoxicity applications. The CS-Te NPs were spherical, polydisperse, and distributed within the CS matrix with an average size of 37.48 ± 14.56 nm, as confirmed by TEM analysis. CS-Te NPs exhibited positive zeta potential in neutral (pH 7.0: 7.90 ± 1.86 mV) and acidic environment. XRD analysis confirmed the crystalline nature of CS-Te NPs, and these nanoparticles exhibited good thermal and less porosity. A higher release of Te ions occurred from CS-Te NPs at an acidic pH. Further, CS-Te NPs displayed stronger antibacterial and antibiofilm activity against E. coli and S. enterica. Furthermore, CS-Te NPs exhibited significant free radical scavenging activity against ABTS and DPPH free radicals. Moreover, these nanoparticles demonstrated cytotoxicity against cancerous cells (A549 and PC3 cells) when compared to normal cells (NIH3T3 cells). Therefore, this study suggests that CS-Te NPs could serve as a substantial therapeutic agent.

PLCD3, a flotillin2-interacting protein, is involved in proliferation, migration and invasion of nasopharyngeal carcinoma cells.

Phospholipase C (PLC) is a pivotal enzyme in the phosphoinositide pathway that promotes the second messengers, diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3), to participate in eukaryotic signal transduction. Several PLC isozymes are associated with cancer, such as PLC-ß1, PLC-δ1, PLC-ε and PLC-γ1. However, the role of PLC-δ3 (PLCD3) in nasopharyngeal carcinoma (NPC) has not been investigated to date. In our previous study, we demonstrated that flotillin2 (Flot2) plays a pro-neoplastic role in NPC and is involved in tumour progression and metastasis. In the present study, we screened the interacting proteins of Flot2 using the yeast two-hybrid (Y2H) method and verified the interaction between PLCD3 and Flot2 by co-immunoprecipitation. We also investigated the biological functions of PLCD3 in NPC. Inhibition of PLCD3 expression impaired the malignant potential of 5-8F, a highly metastatic NPC cell line, by restraining its growth, proliferation, mobility and migration. The present study demonstrated that PLCD3 may be an oncogenic protein in NPC and that it plays an important role in the progression of NPC partially by interacting with Flot2.

Embryotoxicity estimation of commonly used compounds with embryonic stem cell test.

The embryonic stem cell test (EST), an alternative model to animal studies, is a reliable and scientifically validated in vitro system for testing embryotoxicity. In contrast to most in vivo animal tests, two permanent cell lines, murine fibroblasts (BALB/c­3T3 cells) and murine embryonic stem cells (mES­D3 cells), are used in EST instead of animals in standard tests of toxicity. The embryotoxic potential of compounds (non, weak or strong embryotoxicity) may be obtained with a biostatistics­based prediction model and calculated from three different experimental endpoint values: The potency to inhibit growth of i) BALB/c­3T3 cells and ii) mES­D3 cells (IC503T3 and IC50ES) as presented using a cell cytotoxicity assay, and iii) the potency to inhibit differentiation of mES­D3 cells into contracting cardiomyocytes (ID50 D3) as demonstrated in a mES­D3 cell differentiation assay. In the present study, a model of EST with mES­D3 cells and BALB/c­3T3 cells was established, according to the standard EST system of the EU Center for the Validation of Alternative Methods, and verified it with 5­fluorouracil (strong embryotoxicity) as a positive control and penicillin G (non­embryotoxic) as a negative control. In addition, the authors further assessed the embryotoxicity of four compounds (eugenol, carnosic acid, procyanidin and dioctyl phthalate) with this model. The embryotoxic potentials of the four compounds were successfully classified by the EST system. Eugenol exhibited strong embryotoxicity, carnosic acid and dioctyl phthalate exhibited weak embryotoxicity, while procyanidin exhibited non­embryotoxicity.

High-Efficient Transfection of Human Embryonic Stem Cells by Single-Cell Plating and Starvation.

Nowadays, the low efficiency of small interfering RNA (siRNA) or plasmid DNA (pDNA) transfection is a critical issue in genetic manipulation of human embryonic stem (hES) cells. Development of an efficient transfection method for delivery of siRNAs and plasmids into hES cells becomes more and more imperative. In this study, we tried to modify the traditional transfection protocol by introducing two crucial processes, single-cell plating and starvation, to increase the transfection efficiency in hES cells. Furthermore, we comparatively examined the transfection efficiency of some commercially available siRNA or pDNA transfection reagents in hES cells. Our results showed that the new developed method markedly enhanced the transfection efficiency without influencing the proliferation and pluripotency of hES cells. Lipofectamine RNAiMAX exhibited much higher siRNA transfection efficiency than the other reagents, and FuGENE HD was identified as the best suitable reagent for efficient pDNA transfection of hES cells among the tested reagents.