Background: Human metapneumovirus (hMPV) is a major cause of acute respiratory infections ranging from wheezing to bronchiolitis and pneumonia in children worldwide. The objective of this study is to develop a visual reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for the detection of hMPV and applied to the clinical samples. Results: In this study, visual RT-LAMP assay for hMPV was performed in one step with the addition of hydroxynaphthol blue (HNB), and were used to detect respiratory samples. Six primers, including two outer primers (F3 and B3), two inner primers (FIP, BIP) and two loop primers (LF and LB), were designed for hMPV N gene by the online software. Moreover, the RT-LAMP assay showed good specificity and no cross-reactivity was observed with human rhinovirus (HRV), human respiratory syncytial Virus (RSV), or influenza virus A/PR/8/34 (H1N1). The detection limit of the RT-LAMP assay was approximately ten viral RNA copies, lower than that of traditional reverse transcriptase polymerase chain reaction (RT-PCR) 100 RNA copies. In the 176 nasopharyngeal samples, 23 (13.1%) were conformed as hMPV positive by RT-LAMP, but 18 (10.2%) positive by RT-PCR. Conclusion: Compared with conventional RT-PCR, the visual hMPV RT-LAMP assay performed well in the aspect of detect time, sensitivity, specificity and visibility. It is anticipated that the RT-LAMP will be used for clinical tests in hospital or field testing during outbreaks and in emergency.

The widespread and excessive use of ivermectin (IVM) will not only cause serious environmental pollution, but will also affect metabolism of humans and other mammals that are exposed. IVM has the characteristics of being widely distributed and slowly metabolized, which will cause potential toxicity to the body. We focused on the metabolic pathway and mechanism of toxicity of IVM on RAW264.7 cells. Colony formation and LDH detection assay showed that IVM significantly inhibited the proliferation of and induced cytotoxicity in RAW264.7 cells. Intracellular biochemical analysis using Western blotting assay showed that LC3-B and Beclin-1 were upregulated and p62 was down-regulated. The combination of confocal fluorescence, calcein-AM/CoCl₂, and fluorescence probe results showed that IVM could induce the opening of the mitochondrial membrane permeability transition pore, reduce mitochondrial content, and increase lysosome content. In addition, we focused on induction of IVM in the autophagy signal pathway. The Western blotting results showed that IVM increased expression of p-AMPK and decreased p-mTOR and p-S6K expression in protein levels, indicating that IVM activated the AMPK/mTOR signaling pathway. Therefore, IVM may inhibit cell proliferation by inducing cell cycle arrest and autophagy.

The invention and use of chelating purification products directed at atmospheric particulate matter 2.5 (PM2.5) are beneficial in preventing cytotoxicity and bodily harm. However, natural plant active compounds that minimize the adverse effect of PM2.5 are rarely reported. Chlorella pyrenoidosa extracts (CPEs), a nutritional supplement derived from Chlorella vulgaris, have been shown to have antioxidant and anti-inflammatory effects. Here, we discovered that CPEs extracted with crushing cell extraction technology can attenuate the negative impacts of PM2.5. Furthermore, CPE intervention can protect against DNA damage and unstable genomic structure due to PM2.5 exposure. Moreover, CPE intervention restored mRNA and protein expression of the DNA misincorporation repair mechanism gene, nudix hydrolase 1 (NUDT1), and 8-oxoguanine DNA glycosylase (OGG1). In vivo damage protection experiments revealed that CPEs reduced PM2.5-induced hepatotoxicity of zebrafish larvae and effectively prevented the death of adult zebrafish exposed to PM2.5. Briefly, CPEs can attenuate cytotoxicity, resist DNA damage, relieve PM2.5-induced hepatotoxicity, and improve cell purification activity, making them ideal for use as a protective factor or functional ingredient in the cosmetics and health food industries.