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SERS spectrum-based error calibration method of TMB–H2O2 colorimetric system to achieve the actual process information during TMB oxidation and open a new horizon for enzyme-linked immunosorbent assays and other biomedical applications.

High-fat diet induces lipid metabolism disorders that has become one of the grievous public health problems and imposes a serious economic and social burden worldwide. Safety probiotics isolated from nature are regarded as a novel supplementary strategy for preventing and improving diet-induced lipid metabolism disorders and related chronic diseases. The present review summarized the latest researches of probiotics in high fat diet induced lipid metabolism disorders to provide a critical perspective on the regulatory function of probiotics for future research. Furthermore, the screening criteria and general sources of probiotics with lipid-lowering ability also outlined to enlarge microbial species resource bank instantly, which promoted the development of functional foods with lipid-lowering strains from nature. After critically reviewing the lipid-lowering potential of probiotics both in vitro and in vivo and even in clinical data of humans, we provided a perspective that probiotics activated AMPK signaling pathway to regulate fat synthesis and decomposition, as well as affected positively the gut microbiota structure, intestinal barrier function and systemic inflammatory response, then these beneficial effects are amplified along Gut-liver axis, which regulated intestinal flora metabolites such as SCFAs and BAs by HMGCR/FXR/SHP signaling pathway to improve high fat diet induced lipid metabolism disorders effectively.

The purpose of this work is to evaluate the possibility of using cellulose nanocrystals (CNC) derived from waste newspaper as a carrier for immobilizing laccases. Firstly, the cellulose nanocrystals extracted from waste newspaper were oxidized with sodium periodate, and the hydroxyl groups on the second and third carbons (C2 and C3) of the CNC molecules were converted to dialdehyde groups. Then, the laccase was successfully immobilized on the dialdehyde-modified cellulose nanocrystals (DMC) through covalent bonding. The DMC was characterized using zeta potential, Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy, and the relationship between the activity of the immobilized laccase and the dialdehyde group content of the DMC was thoroughly investigated. It was found that the yield of the laccase immobilization is 64.94%, and the highest activity of the immobilized laccase (1.108 U/mg) is obtained at an aldehyde content of the DMC equal to 50.64%, a mass ratio of the carrier to the laccase equal to 45:3, a pH of 4.5, and a reaction time of 2 h. Compared to the free laccase, the immobilized laccase exhibits excellent stability in a wider range of pH values and temperatures. Furthermore, the immobilized laccase showed excellent reusability as evidenced by its retained relative activity of 67% after 6 cycles.

Quantitative characterization of Cr3+, an important element revealing human metabolism and biological environmental variation, is still difficult to achieve by conventional biochemical methods due to the lack of high-sensitivity, real-time techniques with rapid response detection. Using surface-enhanced Raman scattering (SERS), we construct an Au/Ag composite-based SERS nanoprobe for the quantitative characterization of Cr3+ content in solution, in which DL-mercaptosuccinic acid (DL-MSA) is employed for Raman signal enhancement, and 4-mercaptobenzoic acid (4-MBA) is chosen as the Raman reporter. The achieved result demonstrates obvious advantages of the synthesized Au/Ag composite-based SERS nanoprobe in sensitivity and response speed. Importantly, this Au/Ag composite-based SERS nanoprobe might provide a new strategy for dynamic monitoring of Cr3+ content in human metabolism.

Cyclophosphamide (CTX) is a widely used anticancer drug that can cause liver injury, but there is no effective treatment available at present. The antioxidant properties of Lactobacillus plantarum Lp2 in vitro and its effect on CTX-induced liver injury in mice were investigated thoroughly. The order of antioxidant capacity of the fermentate of Lp2 was as followed: fermented supernatant cell-free extract intact cell. BALB/c mice were intraperitoneally injected with 80 mg/kg BW/d CTX for 3 days to build a liver injury model, then treated with Lp2 fermented supernatant (Lp2-s) and Lp2 culture broth (Lp2). After 10 days, the indicators of oxidative stress and liver injury were measured. Both Lp2-s and Lp2 restored the levels of T-SOD, CAT, GSH-Px, MDA, GSH, ALT, and AST. The western blotting results showed that Lp2-s and Lp2 ameliorated CTX-induced oxidative damage and hepatocyte apoptosis via inhibiting MAPKs pathway and strengthening Nrf2/HO-1/NQO1 antioxidant defense system, thus inhibiting the mitochondrial-mediated apoptosis pathway. Therefore, both Lp2-s and Lp2 had similar protective effects on CTX-induced liver injury.

Lignin is utilized as a carbon precursor to produce microporous lignin-derived carbon-based solid acid (MLC-S) ZnCl2 activation and sulfonation with concentrated sulfuric acid. The effects of reaction conditions, namely the ratio of methanol to oleic acid, carbonization temperature, and catalyst dosage, on the efficiency of the esterification of oleic acid with methanol are investigated. As a carbon-based solid acid, the MLC-S offers high catalytic activity in the esterification, which is a crucial reaction in the synthesis of biodiesel. Compared with nonactivated lignin-derived carbon-based solid acid (LC-S), the highly porous structure of the MLC-S makes its active sites more accessible and ensures its excellent catalytic performance. Under the optimal conditions, the esterification of oleic acid with methanol reaches a conversion of 92.3%. Moreover, after recycling the MLC-S for five times, the extent of the esterification reaction is still as high as 72.9%. Obviously, the synthesized MLC-S has considerable potential for the esterification of oleic acid with methanol and thus for biodiesel production.

Based on the local electric field enhancement of gap-mode surface plasmon resonance, the plasmonic particle-on-film nanocavity (PPoFN) can realize Raman signal enhancement of multiple orders of magnitude, even single molecule detection. The tightly focused radially polarized (Bessel-Gaussian) beam (TFRPB), containing a cylindrical symmetry longitudinal component, is a superior excitation source for PPoFN to generate a more intriguing electromagnetic hot spot in the gap. For the optical response of PPoFN in TFRPB, some theoretical and experimental studies at a certain wavelength have been reported, but a full-wave analysis about the near- and far-field optical properties is still lacking because it is still difficult to generate a full-wave radially polarized beam and achieve a dispersion-free confocal light field in the experiment. In this paper, we analyze the full-wave near- and far-field optical properties of PPoFN in TFRPB by using numerical simulation with the finite element method (FEM). For comparison, a full-wave analysis of PPoFN in tightly focused linearly polarized (Gaussian) beam (TFLPB) is also implemented. Based on the comprehensive results of local field enhancement, nanofocusing property, and far-field radiation, it is found that the PPoFN in TFRPB with the strongest toroidal dipole (TD) mode at a certain wavelength can achieve good performance in Raman signal excitation and detection. Importantly, this result will provide a theoretical reference for the application of PPoFN in tightly focused vector beam.

China, a big paper-making country, produced hundreds of millions of tons of waste paper which contain a lot of fiber every year. Cellulose nanocrystals were extracted from recycled waste paper which can be a high value utilization of secondary fiber. In this paper, cellulose nanocrystals were successfully extracted from waste paper fibers via two different systems, sulfuric acid hydrolysis (SCNCs) and one-step ammonium persulfate (APS) oxidation (OCNCs). This not only broadened the methods of extracting CNCs from waste paper, but also improved the dispersion and reactivity of CNCs. The CNCs products were investigated by FT-IR spectroscopy for functional group structure, X-ray diffraction for crystal structure, TG-DTG for thermal stability and scanning electron microscope, transmission electron microscope for morphology. The results showed that both OCNCs and SCNCs were a rod-like structure. The crystallinity of OCNCs and SCNCs increased to 72.45 and 77.56, but with a low yield of 22.42% and 41.22%, respectively. The result also suggested H2O2 formed by decomposition of APS, selectively oxidized the hydroxyl on the C6 in cellulose to carboxyl, introduced 0.57 mmol/g carboxyl. Successful preparation of CNCs extracted from waste paper can effectively utilize the fiber resources in waste paper, thus transforming into higher economic benefits.

Dendrobine has potential advantages in suppressing atherosclerosis (AS). FK506-binding protein 1A (FKBP1A) is implicated in the regulation of autophagy, inflammation, and apoptosis. To reveal the mechanism by which dendrobine inhibits AS by modulating autophagy, oxidative stress, apoptosis, and senescence. An in vitro AS cell model was induced by culturing human umbilical vein endothelial cells (HUVECs) with oxidized low-density lipoprotein (ox-LDL). The cells were treated with dendrobine alone or in combination with short hairpin RNA (shRNA) targeting FKBP1A or together with 3-methyladenine (3MA), an autophagy inhibitor. Inflammatory cytokines levels tumor necrosis factor-α, interleukin-6 (IL-6), and IL-1β were analyzed and oxidative stress levels were detected by the analysis of reactive oxygen species, malondialdehyde, and superoxide dismutase levels, followed by the analysis of apoptosis levels through terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Cell senescence was evaluated by senescence-associated β-galactosidase and light chain 3 (LC3) levels were detected by immunofluorescence (IF) staining. The targeting relationship of dendrobine and FKBP1A was predicted by SwissTarget, PyMol, Autodock, and Open Babel software. Dendrobine reduced the levels of proinflammation factors, oxidative stress levels, apoptosis levels, and senescence phenotype in ox-LDL-induced HUVECs. Besides, cell viability has an opposite change. Furthermore, there was an increase in LC3 IF tensity, and LC3-II/I and Beclin1 expressions, and a decrease in p62 expression. However, these effects of dendrobine could be markedly destroyed by shRNA silencing FKBP1A and 3MA. Dendrobine can suppress inflammatory responses, oxidative stress, apoptosis, and senescence via FKBP1A-involved autophagy ox-LDL-treated HUVECs.

Off-axis interferometric modules built on an ordinary bright field microscope make it possible to achieve single-shot quantitative phase imaging (QPI) by adding sufficient spatial carrier into the interferograms. However, compared with its on-axis counterparts, imaging configurations for off-axis interferometric modules have several disadvantages regarding optical aberration, stability, and space-bandwidth utilization of the lenses system. Herein, by demultiplexing technology based on polarization gratings, we propose a single-shot spatial light interference microscopy named as polarization-multiplexing light interference microscopy (PLIM) with on-axis imaging configuration to realize single-shot QPI. Although the imaging system is on-axis, the PLIM system still can generate sufficient spatial carrier, so we can adjust the orientation and absolute value of the spatial carrier independently of the magnification ratio of the imaging system. The experimental results prove that the PLIM system has better temporal phase stability compared with conventional grating-based QPI technologies and is suitable for high resolution QPI.

Hydrogen peroxide (H

Quantitative characterization of Cr

The effective and safe capture and storage of radioactive iodine (129I or 131I) are of significant importance during nuclear waste storage and nuclear energy generation. Herein, a porous silicon–carbon (pSi–C) composite derived from paper mill sludge (PMS) is synthesized and used for rapid iodine capture. The influences of the activator type, the impregnation ratio of the paper mill sludge to the activator, carbonization temperature, and carbonization time on the properties of the pSi–C composite are investigated. The pSi–C composite produced in the presence of ZnCl2 as the activator and at an impregnation ratio of 1 : 1, a carbonization temperature of 550 °C, and a carbonization time of 90 min has a surface area of 762.13 m2 g−1. The as-synthesized pSi–C composite exhibits promising iodine capture performance in terms of superior iodine adsorption capacity (qt) of around 250 mg g−1 and rapid equilibrium adsorption with in 15 min. The devised method is environmentally friendly and inexpensive and can easily be employed for the large-scale production of porous silicon-activated carbon composites with excellent iodine capture and storage from iodine-contaminated water.

Phototherapy, especially the photothermal therapy (PTT) and the photodynamic therapy (PDT), have become very promising in cancer treatment due to its low invasiveness and high efficacy. Both PTT and PDT involve the utilization of light energy, and their synergistic treatment should be a good solution for cancer treatment by ingenious design. The therapeutic effect of phototherapy is closely associated with the amount and location of anticancer-nanodrugs accumulated in tumor cells, and the receptor-mediated endocytosis should be an excellent candidate for enhancing anticancer-nanodrugs internalization. Surface enhanced Raman spectroscopy (SERS) imaging is suitable for tracing nanodrugs due to its high selectivity, sensitivity and reliability. In this paper, we hope to construct a receptor-mediated PTT/PDT synergistic anticancer nanodrugs and evaluate the corresponding efficacy through SERS tracing function. Here, the receptor-mediated PTT/PDT synergistic anticancer nanodrugs are prepared by the chemical modification of gold nanorods (GNRs), involving protoporphyrin IX (PpIX), 4-mecaptobenzoic acid (MBA), and folic acid (FA). The achieved results show that the receptor-mediated endocytosis can greatly facilitate the internalized amount and intracellular distribution of the nanodrugs, thus lead to the anti-cancer efficacy improvement. Importantly, this receptor-mediated PTT/PDT synergistic treatment with SERS tracing function will provide a simple and effective strategy for the design and application of anticancer phototherapy nanodrugs.

Though it has been demonstrated that Chidamide (CS055/HBI-8000), a novel benzamide class of histone deacetylase (HDAC) subtype-selectively inhibitor, reveals better anticancer effect in acute leukemia, but it remains unknown about the precise mechanism of Chidamide-induced acute leukemia cell apoptosis due to the lack of in situ molecular changes information. Based on Raman spectral analysis, we find that the action of Chidamide on Jurkat cell will lead to an addition of an acetyl group to a specific lysine residue at the end of histone amino acid, and greatly enhance the acetylation of histones H1, H2A, H2B, H3, and H4, and then destroy the electrostatic force between the alkaline terminal of the positive charged arginine side chain and the negative charged DNA of phosphate group, finally cause the depolymerization of DNA and histone octamer in chromatin nucleosome depolymerization and the relaxation of chromatin. Accordingly, the accumulation of reactive oxygen species (ROS) and the decreasing of mitochondrial membrane potential (MMP) are observed. For comparison, we also present the corresponding results of suberoylanilide hydroxamic acid (SAHA) and MS-275 inhibitors. The achieved results show that proliferation of Chidamide-treated Jurkat cells is low relative to MS-275 or SAHA, and the action of Chidamide or MS-275 on Jurkat cells lead to obvious increasing in histones H1, H2A, H2B, H3, and H4, whereas the action effect of SAHA is mainly observed in histones H1, H2A, H2B, H3 but weak in histone H4. Moreover, it is found that Chidamide-induced histone H3 acetylation in Jurkat cells is stronger than MS-275 and SAHA. Collectively, by Raman spectral analysis, we achieve the dynamic behavior of biochemical components, molecular conformation and morphological changes of HDAC inhibitors-treated Jurkat cells. Importantly, our research is the first to demonstrate that the action site of HDAC inhibitors on Jurkat cell is located in the DNA minor groove. Most importantly, the application of Raman spectrum in exploring in-situ molecular changes information, histone acetylation modification in epigenetics, drug action sites and cell cycle affected by HDAC inhibitors will supply new idea and reference for the design and modification of HDAC inhibitors.

Background: Chemotherapy and radiotherapy are common methods of cancer treatment, but they are accompanied by serious side effects. Actually, many cancer cells have overexpression of folic acid (FA) receptor and by FA receptor-mediated endocytosis, anticancer drugs can be easily internalized into cancer cell, this will greatly improve the curative effect and decrease side effects. Along with the development of nanotechnology, phototherapy, owning advantages in tissue selectivity, process controlling, low toxicity and reproducible treatment, has become very promising, especially for photothermal therapy (PTT) and photodynamic therapy (PDT). Since both PTT and PDT involve the utilization of light energy, so they synergistic treatment should be a good solution by ingenious design. In this paper, based on surface enhanced Raman spectroscopy (SERS) imaging, we hope to construct a FA receptor-mediated PTT/PDT synergistic anticancer nanodrug (nanoprobe), and achieve the intracellular distribution information of the nanodrugs during cell apoptosis, and then elucidate PTT/PDT-induced cell apoptosis and synergistic efficiency.Results: FA receptor-mediated PTT/PDT synergistic anticancer nanodrugs with tracing function are prepared by the chemical synthesis and modification of gold nanorods (GNR), involving protoporphyrin IX (PpIX), 4-mecaptobenzoic acid (MBA), and FA. Based on SERS imaging, it is found that the FA receptor-mediated endocytosis can greatly facilitate the nanodrugs internalization, in which both the number and intracellular dispersion of the PpIX-GNR-MBA-FA nanodrugs are improved relative to the GNR-MBA or PpIX-GNR-MBA compositions, and then enhance the PTT/PDT-induced cell apoptosis.Conclusion: SERS imaging is very suitable for the phototherapy tracing due to its high sensitivity and stability. The FA receptor-mediated way can significantly facilitate nanodrugs internalization, PTT/PDT-induced cell apoptosis and synergistic efficiency. Importantly, this FA receptor-mediated SERS imaging based PTT/PDT synergistic treatment will provide a novel strategy for the design and application of anticancer phototherapy nanodrugs.

Quantitative characterization of intracellular H

Mitoxantrone (MTX), one representative of anthraquinone ring anticancer drugs, reveals excellent anticancer effects in acute leukemia. Though current studies have shown that MTX-induced acute leukemia cell apoptosis is implemented by inserting into DNA, and then leading to DNA breakage and the subsequent transcription termination, but the specific location information of MTX embedded in DNA remains unknown. In this study, combining surface enhanced Raman scattering (SERS) and principal component analysis (PCA), we achieve the biochemical changes of MTX-induced Jurkat cell apoptosis and the location information of MTX embedded in DNA. In contrast, we also present the corresponding result of Daunorubicin (DNR)-induced Jurkat cell apoptosis. It is found that the location of MTX embedded in DNA of Jurkat cell is different from DNR, in which the action site of MTX is mainly implemented by blocking and destroying AT base pairs while DNR is performed by embedding and destroying GC base pairs and then the base A. Clearly, this achieved information is very useful for the designing and modification of anthraquinone ring anticancer drugs.

Quantitative characterization of intracellular H2O2 content, which is still difficult by the conventional biochemical methods due to the lack of real-time and non-invasive technique of single cell measurement, is a useful solution for cell state assessment. Based on the surface enhanced Raman scattering (SERS), we construct a novel boric acid (BA) nanoprobe to perform quantitative characterization of H2O2 content, in which the p-thiol benzene boric acid (4-MPBA) reporter molecule modified with gold nanorods (AuNRs) is employed for Raman signal enhancement. The achieved result demonstrates obvious advantages of the synthesized AuNRs/4-MPBA/BA nanoprobe in measurement sensitivity of H2O2 content. Importantly, this AuNRs/4-MPBA/BA nanoprobe will provide a powerful tool for dynamic monitoring and quantitative characterization of intracellular H2O2 content during cell apoptosis or other cell growth processes, and then achieve important reference data for studying the corresponding molecular mechanism.

The power fluctuation of wind farm will affect the operation of regional power grid, mainly due to the power fluctuation caused by voltage fluctuation. In order to submit information to power dispatching department as soon as possible, it is convenient for system dispatching. It is necessary to research and develop wind power forecasting technology, especially ultra-short term wind power forecasting technology. At present, the power forecasting system of the dispatching side and some wind farms in China has been widely used. However, the system has some shortcomings in stable operation. Combined with the actual production experience of the existing wind power prediction system, analyze the performance of the existing wind power prediction system, find out the problems that affect the smooth operation of the system, and refer to domestic and foreign data to provide targeted information for each problem. Finally, some constructive optimization Suggestions and a set of optimization scheme are given. In addition, according to the final proposed solution, this paper also developed an optimization model for wind power prediction system, and compared the changes in system performance before and after optimization to verify whether the optimization plan is correct.

The wind power is a vigorously developed clean energy in China recent years. It’s installed capacity of our country is increasing year by year. Since 2012, the new wind power installed capacity in China has became the first place all around the world. By the end of 2016, our wind power installed capacity has added a total of 87 million 580 thousand kilowatts. Besides the rapid growth of wind power, there are still many problems in China’s wind power business. In order to solve the following problems: the inspection environment of the wind farm equipment is quite complex, the efficiency is not high enough, and the statistical data of the inspection is not good enough, this paper puts forward the “full digital monitoring and inspection platform of wind farm based on AR augmented reality” as the solution of the problems. The project implements fan positioning, model-assisted inspection, process recording, and expert remote assistant APP functions. It promotes the development of wind farm detection and inspection, which can greatly improve the inspection efficiency of wind farms and reduce the workload of inspectors.

ICU readmission is associated with longer hospitalization, mortality and adverse outcomes. An early recognition of ICU readmission can help prevent patients from worse situation and lead to lower treatment cost. As the abundance of Electronics Health Records (EHR), it is popular to design clinical decision tools with machine learning techniques manipulating on healthcare large scale data. To this end, we designed data-driven predictive models to estimate the risk of Intensive Care Unit (ICU) readmission. The discharge summary of each hospital admission was carefully represented by natural language processing algorithms. Unified Medical Language System (UMLS) was further used to standardize inconsistency of discharge summaries. 5 machine learning classifiers including naive Bayes, support vector machine, logistic regression, gradient boosting decision tree and 2 feature representations including Bag-of-Words and Bag-of-CUIs were adopted to construct predictive configurations. The best configuration yielded a competitive AUC of 0.748. High contribution words and medical terms were further investigated to ensure that they were clinical meaningful. A comparative study between two feature representations were also discussed. Our work suggests that natural language processing of discharge summaries is capable to extract meaningful information from discharge summary automatically and to send clinicians the warning of unplanned 30-day readmission upon discharge.