Fluorescent labelling combined with confocal differential Raman spectroscopy to detect microplastics in seawater.

As an emerging marine pollutant, microplastics represent a focal point in global monitoring and management efforts. With seawater accounts for 97 % of the total global water resources, scientific assessments of microplastics in seawater are crucial for pollution control and management of marine environments. This study focuses on investigating microplastics in near-shore seawater and proposes a rapid and accurate detection method using a constructed confocal Raman spectroscopy detection system. By optimizing the pretreatment process of seawater microplastic samples, the efficient removal of organic matter interference in microplastic detection is achieved. Employing fluorescent labeling addresses the issues of prolonged detection time and high false positive rates associated with traditional methods, enabling rapid differentiation between microplastics and other substances and significantly enhancing detection efficiency and accuracy. Additionally, the use of differential Raman spectroscopy effectively mitigates fluorescence signal interference, thus improving the signal-to-noise ratio of the spectra. By employing dual-wavelength laser excitation at 784 nm/785 nm, microplastics such as polyethylene (PE), polypropylene (PP), polystyrene (PS) ranging in size from 60 to 500 µm are successfully detected in seawater. The results demonstrate that the proposed pretreatment method for seawater microplastics and novel detection techniques enable rapid screening and comprehensive non-destructive detection of microplastics in seawater, thereby facilitating the characterization of marine microplastics and providing scientific support for enhancing the management of microplastic pollution and ecological risk control.

Detection of microplastics based on splicing grating spatial heterodyne Raman spectroscopy.

As a new type of persistent pollutant, microplastics pose a serious threat to the earth's ecological environment and human health. Efficient and reliable microplastic detection technology is of great significance in the management of microplastic pollution. Aiming at the problems of low signal-to-noise ratio (SNR), narrow spectral range and low spectral resolution in traditional microplastic detection technology, a splicing grating spatial heterodyne Raman spectroscopy (SG-SHRS) is proposed in this paper. The splicing grating is composed of four sub-gratings with groove densities of 320, 298, 276 and 254 gr / mm, respectively. Each sub-grating has an independent sub-filter to improve the SNR of the system. The system is simulated, built and calibrated. The actual resolution of the SG-SHRS system is 0.7 cm-1, and the spectral detection range of a single sub-grating is 2947.2 cm-1. Four kinds of microplastics, polyamide (PA), polystyrene (PS), polycarbonate (PC), and polyphenylene sulfide (PPS), were detected by the SG-SHRS system. The complete Raman spectral information of microplastics was obtained, and the peak assignment of Raman characteristic peaks of the four kinds of microplastics was analyzed. By comparing the test results with a commercial dispersion spectrometer, it has been proven that the SG-SHRS system has the advantages of high spectral resolution, wide spectral range, and high SNR, and has good application prospects in the field of microplastic detection.

Evaluation of the digestibility and antioxidant activity of protein and lipid after mixing nuts based on in vitro and in vivo models.

This study aimed to evaluate the change of digestibility and antioxidant activity of protein and lipid after mixing walnuts, cashews, and pistachios using in vitro and in vivo models. The results showed that mixed nuts significantly reduced the digested particle size and the degree of hydrolysis of protein and triacylglycerol compared to single nuts in vitro. As a consequence of co-digestion, bioaccessibility and antioxidant activity for amino acids and fatty acids were increased by 1.12-1.87 fold and 1.62-3.81 fold, respectively. In vivo studies, the mixed nuts diet increased the concentration of amino acids and fatty acids in the small intestine by 27.69%-158.26% and 18.13%-152.09%, respectively, and enhanced levels of antioxidant enzymes in the liver and serum, all without causing weight gain. These findings highlight the positive interaction between single and mixed nuts, where mixed nuts enhanced the digestibility and antioxidant activity of single nuts both in vitro and in vivo.

LncRNA ZEB1-AS1 regulates hepatocellular carcinoma progression by targeting miR-23c.

BACKGROUND: It has been reported that long-chain non-coding RNA (lncRNA) zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) is an oncogene in various cancers, including hepatocellular carcinoma (HCC). We investigated the role and mechanism of ZEB1-AS1 as a competitive endogenous RNA (ceRNA) combined with miR-23c in HCC cell proliferation and invasion. METHODS: QRT-PCR was used to detect ZEB1-AS1 and miR-23c expressions in HCC tissues and cells. The dual luciferase reporter assay detected the targeted regulation of miR-23c and ZEB1-AS1. We also performed the correlation analysis of their expression in HCC tissues by the Spearman's correlation analysis. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect the proliferation of hepatoma cells. Cell invasion was assessed by the Transwell assay. RESULTS: QRT-PCR results indicated ZEB1-AS1 was upregulated and miR-23c was downregulated in HCC tissues and cell lines. ZEB1-AS1 knockdown hampered the proliferation and invasion of HCC cells. Dual luciferase reporter assay showed that miR-23c is a target of ZEB1-AS1, and ZEB1-AS1 was significantly negatively correlated with the miR-23c expression in HCC tissues. The results of MTT and Transwell assay showed that miR-23c inhibition restored the inhibitory effect of ZEB1-AS1 knockdown on HCC cells proliferation and invasion. CONCLUSIONS: As a ceRNA, lncRNA ZEB1-AS1 may play a vital role in inhibiting HCC progression through miR-23c, which will provide new clues and theoretical basis for the HCC diagnosis and treatment.

Upregulation of miR-1825 inhibits the progression of glioblastoma by suppressing CDK14 though Wnt/ß-catenin signaling pathway.

BACKGROUND: Mounting evidences displayed that miRNAs play crucial roles in tumor initiation and development. However, the regulation and relevant mechanism of miR-1825 in glioblastoma (GBM) remain unclear. METHODS: qRT-PCR was used to detect miR-1825 and CDK14 mRNA expression. Western blot was applied for testing protein levels (VEGF, E-cadherin, N-cadherin, vimentin, ß-catenin, c-myc, p-c-Jun). MTT and transwell assays were used for detecting GBM cell progression, including cell viability, migration, and invasion. RESULTS: The results showed that miR-1825 was decreased in GBM tissue specimens by qRT-PCR and it was confirmed as a prognostic marker of GBM by Kaplan-Meier survival analysis. Moreover, we also found that miR-1825 upregulation suppressed GBM cell viability, tumor growth, invasion, and migration. Furthermore, CDK14 was first identified as the direct target of miR-1825 by Luciferase reporter assay. CDK14 acted as an oncogene in GBM development by immunohistochemistry. In addition, Western blot analysis demonstrated that miR-1825 regulated Wnt/ß-catenin signaling pathway in GBM development. CONCLUSION: In conclusion, miR-1825 upregulation suppressed GBM progression by targeting CDK14 through Wnt/ß-catenin pathway.

Expression and clinical significance of nestin in astrocytic tumors.

PURPOSE: This study aimed to investigate the expression and clinical significance of nestin in human astrocytic tumors. METHODS: Indirect immunofluorescent staining and flow cytometry were used to quantitatively detect the nestin content in 35 specimens, including 3 normal brain tissues, 29 astrocytic tumor (AT) tissues, and 3 peritumoral tissues. RESULTS: In normal brain tissues, nestin expression was extremely low. Nestin expression was significantly positively correlated with the histological grade of astrocytic tumors (p<0.05, rs=0.83). Nestin content in the peritumoral tissues was between the levels of nestin in tumor tissue and in normal brain tissue (p<0.01). Nestin expression was unrelated to the patient's gender, age, tumor location, size, etc. (p>0.05). CONCLUSION: The application of flow cytometry in the determination of nestin content could improve the accuracy of early cancer diagnosis. This method would be helpful for developing a reference range that is closely related to the pathological grading of ATs through routine assessments of nestin in many patients. Additionally, through examining nestin levels in peritumoral tissues, the invasiveness of ATs can be clarified.