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Nowadays, trace detection of thiram is in urgent demand due to its widespread application in agriculture and significant harmful effects on public health. In this work, a three-dimensional (3D) sea cucumber-like flexible porous surface-enhanced Raman scattering (SERS) substrate composed of a poly(vinylidene fluoride) (PVDF) membrane, ZnO nanorods, gold films, and Ag nanoparticles (Ag/Au/ZnO/P) has been established for the highly sensitive detection of thiram. The substrate takes advantage of the 3D morphology of the Ag/Au/ZnO system on a flexible porous PVDF membrane to produce abundant plasmonic hot spots. Meanwhile, the employment of an AgNPs/Au shell system combined the benefits of both gold and silver metals, thus guaranteeing stable and sensitive detection. With 4-mercaptobenzoic acid (4-MBA) as a probe molecule, the Ag/Au/ZnO/P substrate exhibited excellent linear detection in the range of 10−11–10−5 M, with a correlation coefficient (R2) of 0.99 and an enhancement cofactor of 7.09 × 107. The substrate exhibited excellent uniformity with a related standard deviation (RSD) value of 3.82% and demonstrated high stability during a 15 d-storage test. In addition, the substrate could detect thiram in an aqueous solution at concentrations as low as 10−10 M with excellent selectivity. Meanwhile, thiram on the surface of apple peel could be easily detected by the Ag/Au/ZnO/P substrate with the "paste-and-peel" method in less than 10 s, and the detection limit could be as low as 0.48 ng cm−2. Overall, the remarkable performance of the Ag/Au/ZnO/P SERS substrate demonstrated its great potential for the environmental monitoring of thiram. [ABSTRACT FROM AUTHOR]

The interactions between adenosine triphosphate‐binding cassette (ABC) transporters and nano‐sized materials are attracting increasing attention, due to their great potential in overcoming the multidrug resistance (MDR) phenomena in cancer treatment. However, the inner mechanisms involved in the interactions are largely unknown. In this study, two commercial quantum dots (QDs), CdSe/ZnS‐MPA and CdSe/ZnS‐GSH, were tested for their interactions with P‐glycoprotein (P‐gp), as well as the relating mechanisms in lung cancer (A549) cells. Both QDs significantly suppressed the gene and protein expressions of P‐gp in A549 cells. To explain this, the gene expressions of nine relating microRNAs (miRNAs) were evaluated. The results indicated a shared up‐regulation of miR‐34b and miR‐185 by both QDs. Furthermore, mimics and inhibitors of miR‐34b and miR‐185 significantly enhanced and suppressed the gene and protein expressions of P‐gp, respectively, confirming the modulatory function of these two miRNAs on P‐gp. Interestingly, expressions of both miRNAs were suppressed during treatment with Cd2+ and doxorubicin, which induced the expression of P‐gp, indicating the universality of these miRNAs‐related mechanisms. Thus, as miR‐34b and miR‐185 participated in the suppression of P‐gp functions in A549 cells they could be interesting targets for the treatment of lung cancer. This paper reported a significant suppression of P‐glycoprotein (P‐gp) expressions by two commercial quantum dots (QDs), CdSe/ZnS‐MPA and CdSe/ZnS‐GSH in lung cancer (A549) cells. These processes were found to be modulated by two microRNAs, miR‐34b and miR‐185, with specific mimics and inhibitors. Interestingly, the modulatory functions of these two miRNAs were also applicable during the treatment with CdCl2 and doxorubicin. [ABSTRACT FROM AUTHOR]

A novel method is reported to discriminate human and animal blood by Raman spectroscopy without complex sample preparation. A partial least squares discriminant analysis model was constructed from a calibration set of Raman spectra from three species of animal blood using 785-nm laser excitation. The discrimination between human and nonhuman blood was calculated by three sigma. Various performance measures, including a blind test and external validation, confirmed the discriminatory performance of the chemometric model. The model provided 100% accuracy in its differentiation between human and nonhuman blood. These results demonstrate that Raman spectroscopy is a promising tool for the discrimination of animal and human blood. [ABSTRACT FROM PUBLISHER]

Adenosine triphosphate-binding cassette (ABC) transporters, including ABCB, ABCC and ABCG families represent general biological defenses against environmental toxicants in varieties of marine and freshwater organisms, but their physiological functions at differential developmental stages of zebrafish embryos remain undefined. In this work, functional expressions of typical ABC transporters including P-glycoprotein (Pgp), multiresistance associated protein 1 (Mrp1) and Mrp2 were studied in zebrafish embryos at 4, 24, 48 and 72 h post-fertilization (hpf). As a result, both the gene expressions and activities of Pgp and Mrps increased with the development of embryos. Correspondingly, 4-72 hpf embryos exhibited an increased tolerance to the toxicity caused by cadmium chloride (CdCl2) and β-naphthoflavone (BNF) with time. Such a correlation was assumed caused by the involvement of ABC transporters in the detoxification of chemicals. In addition, the assumption was supported by the fact that model efflux inhibitors of Pgp and Mrps such as reversine 205 and MK571 significantly inhibited the efflux of toxicants and increased the toxicity of Cd and BNF in zebrafish embryos. Moreover, exposure to CdCl2 and BNF induced the gene expressions of Pgp and Mrp1 in 72 hpf embryos. Thus, functional expressions of Pgp and Mrps increased with the development of zebrafish embryos, which could cause an increasing tolerance of zebrafish embryos to CdCl2 and BNF. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this study, gene expression alterations of phase I to III enzymes, transcription factors, and microRNA (miRNA) in embryonic zebrafish fibroblasts (ZF4) cells after the treatment of Pb(NO3)2 and AgNO3 were investigated, to illustrate the possible detoxification pathway of heavy metal ions. It was observed that both metals caused concentration‐dependent death and moderate elevation of oxidative stress in ZF4 cells. In response to such toxicity, upregulation of multidrug resistance protein (mdr)4 and multiresistance‐associated protein (mrp)1 were found. However, enhanced expression of glutathione S‐transferase (gst) and cytochrome P450 (cyp)1a could only be detected during the exposure of Pb2+. In addition, both metals induced extensive upregulation of pregnane X receptor (pxr), but only moderate elevation of E2‐related factor (nrf2), while they suppressed the expression of miR‐122 and miR‐126. In conclusion, Pb2+ and Ag+ shared the same detoxification mechanism including ABC transporters, Pxr, and miRNA in ZF4 cells, which needs further investigation. [ABSTRACT FROM AUTHOR]

Background: Cancer is a major disease that threatens human life and health. Raman spectroscopy can provide an effective detection method., Objective: The study aimed to introduce the application of Raman spectroscopy to tumor detection. We have introduced the current mainstream Raman spectroscopy technology and related application research., Methods: This article has first introduced the grim situation of malignant tumors in the world. The advantages of tumor diagnosis based on Raman spectroscopy have also been analyzed. Secondly, various Raman spectroscopy techniques applied in the medical field are introduced. Several studies on the application of Raman spectroscopy to tumors in different parts of the human body are discussed. Then the advantages of combining deep learning with Raman spectroscopy in the diagnosis of tumors are discussed. Finally, the related problems of tumor diagnosis methods based on Raman spectroscopy are pointed out. This may provide useful clues for future work., Conclusion: Raman spectroscopy can be an effective method for diagnosing tumors. Moreover, Raman spectroscopy diagnosis combined with deep learning can provide more convenient and accurate detection results., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

In recent decades, organophosphorus (OP) pesticides are widely used in agricultural and domestic fields. There is increasing demand for more rapid and economical methods of detecting pesticide residues. We have developed a gold immunochromatography assay (GICA) strip test for detecting a group of OP pesticides based on monoclonal antibodies (MAb) against a generic hapten, O,O-diethyl O-(4-carboxy-3-methylphenyl) phosphorothioate. The MAb showed desirable properties for use in indirect competitive ELISA, and the minimum IC50 value (93 ng/mL) was observed in chlorpyrifos-ethyl curve. The partially purified monoclonal antibodies were conjugated with colloidal gold particles. The conjugation of the colloidal gold and antibodies was monitored by ultraviolet-visible (UV-vis) spectroscopy and fluorescence spectroscopy, while the transmission electron microscopy (TEM) images were used to characterize the particle size and shape of the conjugates. Dynamic light scattering (DLC) was applied as a less expensive and faster method to substitute TEM. The colloidal gold and antibody conjugates were used for the production of a GICA strip test to detect OP pesticides. Preliminary assessment suggests that the OP pesticide, chlorpyrifos-ethyl (CE), in environmental samples could be detected by the GICA strip. This assay could potentially be used for screening large volume of samples and on-spot monitoring before the precise analysis. But the homogeneity of the detection needs to be improved further.

Using atomic force microscope (AFM), we investigated the images of Pars influenza virus (PIV) under different treatment conditions and observed the different appearances of the virus and its ultra-microstructure from the exterior to the interior. From the 2D images under transmission electron microscope (TEM), we could see that the surfaces of PIV particles exhibited spherical and band-shaped 'tufts'; from the 3D images under AFM, we could further observe the whole spherical virus particles and their detailed surfaces, which exhibited round and band-shaped 'tufts'. Comparing the images under TEM with those under AFM, we found that the latter could reveal the surface topograph and ultramicrostructure of viruses more truly than did the former. The samples of viruses were treated by Tritonx-100, the lipid envelopes of virions were partly or completely resolved, and then most of their capsids were exposed. We could observe the different appearances of the virions under AFM, the lipid envelopes of which were gradually removed. The samples of viruses were also treated by SDS, and the RNA was released from the virions. From the AFM images, we could see the structure of the RNA. It was thus clear that AFM could be used to investigate the different appearances and ultramicrostructure of viruses rapidly and efficiently.