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The human gut microbiome is a complex system composed of hundreds of species, and metaproteomics can be used to explore their expressed functions. However, many lower abundance species are not detected by current metaproteomic techniques and represent the dark field of metaproteomics. We do not know the minimal abundance of a bacterium in a microbiome(depth) that can be detected by shotgun metaproteomics. In this study, we spiked

Breast cancer being one of the most common malignant tumours among women, diagnostic modalities for early detection of the same become of paramount importance. In this context, the hand-held ultrasound (HHUS) and automated breast volume scanner (ABVS) could provide valuable information for clinicians to diagnose breast diseases. This study aimed to compare and evaluate the diagnostic performance of combined use of HHUS and ABVS for the differentiation of benign and malignant breast lesions.A total of 361 female patients, who underwent both HHUS and ABVS examinations were included in this study. ABVS and HHUS images were interpreted using the American College of Radiology Breast Imaging-Reporting and Data System (BI-RADS). The distributions of the BI-RADS categories and pathology results were shown as specific numbers. Kappa coefficients test (κ) was calculated to compare the diagnostic results amongst the ABVS, HHUS and ABVS combined with HHUS. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of the three diagnostic methods were calculated and their respective diagnostic performance was analyzed by receiver operator characteristic curve.Of a total of 431 lesions, 153 (35.5%) were malignant and 278 (64.5%) were benign. With respect to the pathology results, the value of κ was 0.713 (P0.001) for HHUS, κ=0.765 (P0.001) for ABVS and κ=0.815 (P0.001) for HHUS+ABVS. The sensitivity, specificity, accuracy, PPV and NPV for HHUS combined with ABVS were 96.08 (147/153), 88.49 (246/278), 91.18 (393/431), 82.12 (147/179) and 97.62 per cent (246/252) respectively. For HHUS, these were 90.20 (138/153), 84.17 (234/278), 86.31 (372/431), 75.82 (138/182) and 93.98 per cent (234/249) respectively; and for ABVS these were 92.16 (141/153), 87.05 (242/278), 88.86 (383/431), 79.66 (141/177) and 95.28 per cent (242/254), respectively. There was no significant difference amongst these three methods, but the diagnostic performance of HHUS combined with ABVS was better than, or at least equal to, that of HHUS or ABVS alone.The results of this study suggest that ABVS is a promising and advantageous modality for breast cancer detection. Furthermore, the combination of HHUS and ABVS showed a more comparable diagnostic performance than HHUS or ABVS alone for distinguishing between benign and malignant breast lesions.

Post-translational modifications (PTMs) play an essential role in most biological processes. PTMs on human proteins have been extensively studied. Studies on bacterial PTMs are emerging, which demonstrate that bacterial PTMs are different from human PTMs in their types, mechanisms and functions. Few PTM studies have been done on the microbiome. Here, we reviewed several studied PTMs in bacteria including phosphorylation, acetylation, succinylation, glycosylation, and proteases. We discussed the enzymes responsible for each PTM and their functions. We also summarized the current methods used to study microbiome PTMs and the observations demonstrating the roles of PTM in the microbe-microbe interactions within the microbiome and their interactions with the environment or host. Although new methods and tools for PTM studies are still needed, the existing technologies have made great progress enabling a deeper understanding of the functional regulation of the microbiome. Large-scale application of these microbiome-wide PTM studies will provide a better understanding of the microbiome and its roles in the development of human diseases.

Subnanometric metal clusters have attracted extensive attention because of their unique properties as heterogeneous catalysts. However, it is challenging to obtain uniformly distributed metal clusters under synthesis and reaction conditions. Herein, we report a template-guidance protocol to synthesize subnanometric metal clusters uniformly encapsulated in beta-zeolite, with the metal ions anchored to the internal channels of the zeolite template via electrostatic interactions. Pt metal clusters with a narrow size range of 0.89 to 1.22 nm have been obtained on the intersectional sites of beta-zeolite (Pt@beta) with a broad range of Si/Al molar ratios (15-200). The uniformly distributed Pt clusters in Pt@H-beta are subject to strong electron withdrawal by the zeolite, which promotes transfer of active hydrogen, providing excellent activity and stability in hydrodeoxygenation reactions. A general strategy is thus proposed for the encapsulation of subnanometric metal clusters in zeolites with high thermal stability.

Background: Curcumin, as a lipid-lowering drug, has been reported to be effective in the treatment of breast cancer. However, the underlying molecular mechanisms have not been completely investigated. Methods: MTT assay was used to determine the effect of curcumin on survival rate of MCF-7 cells. The effects of curcumin on tumor growth were observed in animal models of breast cancer. The positive reactions of Caspase-1, IL-1β and IL-18 were detected by immunohistochemistry. LC3, p62, CTSB, ASC, Pro-Caspase-1, GSDMD, NLRP3, Caspase-1, GSDMD-N, IL-1β and IL-18 were determined by Western blot in vitro and vivo. The release of extracellular IL-1β and IL-18 was determined by ELISA. LDH release was measured. The expression level of CTSB in cytoplasm were determined by immunofluorescence assay. Cell proliferation, cell migration and tube formation assays were used to determine the abilities of cells. In this study, NLRP3 inflammasome inhibitor MCC950, cathepsin B inhibitor CA-074 ME and autophagy inhibitor 3-MA were used to act on cells to investigate the role of NLRP3 inflammasome, cathepsin B and autophagy in curcumin-induced pyroptosis of MCF-7 breast cancer cells.Results: In mouse model of breast cancer, we observed that curcumin treatment significantly induced cell autophagy and pyroptosis. In human breast cancer MCF-7 cells, we found that curcumin induced pyroptotic cell death was dependent on the activation of NLRP3/Caspase-1/GSDMD signaling pathway, which was CTSB-dependent. In addition, curcumin-induced cell autophagy caused lysosomal rupture and CTSB release. Furthermore, NLRP3 inhibitor (MCC950) significantly suppressed curcumin-induced pyroptosis, as well as CTSB inhibitor (CA074 Me) and autophagy inhibitor (3-MA). Besides, we also found that curcumin suppressed cell proliferation, cell migration and tube formation, which could be reversed by inhibitors. Conclusions: In summary, our results demonstrated that curcumin induced MCF-7 cell pyroptosis by the activation of autophagy/CTSB/NLRP3/Caspase-1/GSDMD signaling pathway. These findings offer novel insights into the potential molecular mechanisms of curcumin in treatment of breast cancer.

Leakage accidents occurring during oil production and transportation are currently one of the most serious environmental problems worldwide. Developing efficient and environmentally friendly oil-water separation methods is the key to solve this problem. In this work, a facile method to fabricate a high-performance oil absorbent through the loading of ball-milled biochar (BMBC) and octadecylamine on the skeleton of melamine foam (MF) is reported. The resulting ball-milled biochar-based MF (BMBC@MF) displayed a complex three-dimensional porous structure. The BM biochar on the surface of BMBC@MF forms nano/μm-scale folds, which reduced the surface energy of BMBC@MF after grafted octadecylamine. These structures resulted in the conversion of the hydrophilic surface of MF to hydrophobic surface. These characteristics made the modified foam an excellent oil absorbent with a high oil absorption capacity (43-155 times its own weight) and extraordinary recyclability. Furthermore, the BMBC@MF could maintain high hydrophobicity and adsorption stability in a wide pH range (from 1 to 11). More importantly, BM biochar is a cheap and readily available material to make BMBC@MF possible for large-scale production. Therefore, this work provides an effective way for low-cost, environmentally friendly, and large-scale production of superhydrophobic adsorbents for oil-water separation.

Novel coronavirus is rampant around the world, causing tens of millions of infections and hundreds of thousands of deaths. Because of its high accuracy, simplicity, convenience and rapidness, medical imaging has become one of the important reference standards for the diagnosis of suspected cases recognized by clinicians. While examining the patients, the imaging department should also strengthen the infection control of medical staff so as to prevent nosocomial infection to the greatest extent. This paper expounds the key points of infection control in medical imaging department from the aspects of personnel configuration, protective equipment management and examination process of medical imaging department, and discusses the key points of infection control from the specific conditions of four departments: CT, ultrasound, magnetic resonance and nuclear medicine.

Segmentation-quantification is the most commonly used method for studying the tissue distribution of bioactive constituents in plant, but this method would bring uncontrollable pollution, compound migration and denaturation. Mass spectrometry imaging (MSI), as a new method developed in the past 20 years, has high sensitivity, high spatial resolution, high degree of visualization, and low risk of contamination and degeneration when studying tissue distribution of compounds. For the first time we applied matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) to tissue distribution of characteristic constituents of the medicinal plant Salvia miltiorrhiza. From the collected data, we found the regional differences in root, stem, and leaf tissues, and the ion information with differential distribution characteristics. We also identified 18 bioactive constituents in S. miltiorrhiza with their spatial distribution information. In addition, the plant was divided into five parts, and the identified compounds were analyzed for differences between tissues using LC-MS, which results verified those found from the MSI. It is figured out that MALDI-MSI can be reliably applied to the differential distribution of salvianolic acids and tanshinones.

Aiming at the acid modification and stabilization of ordered mesopores in HZSM-5 nanosheet (NS) zeolite for catalytic cracking, two kinds of Fe-modified NS zeolite catalysts were prepared by incipient wetness impregnation (Fe/NS) and an in-situ hydrothermal synthesis method (Fe@NS, N-[3-(trimethoxysilyl)propyl]ethylenediamine complexed Fe as precursors). Fe modification conveyed a lower n-heptane cracking conversion by the Fe/NS catalyst because of the decreased total acid content compared with the parent NS catalyst. However, the decreased Bronsted to Lewis acid ratios by Fe modification restricted the deep hydrogen transfer of olefins, leading to an enhanced ethylene and propylene yields in the product. Furthermore, for Fe@NS catalyst, the highly dispersed FeOx between the nanosheet layers stabilized the mesopore arrangement, and the facilitated diffusion by highly connected channels further alleviated olefin consuming. At reaction temperature of 550 °C with a weight hourly space velocity of 8.64 h−1, a 41.8 wt% yield of light olefins (ethylene of 12.2 wt% and propylene of 29.6 wt%) by the Fe@NS catalyst was realized, which was 10.4% and 21.7% higher than that of the Fe/NS and parent NS catalysts, respectively. Moreover, Fe@NS also showed a good catalytic stability with a deactivation rate of only 4.37% after 18 h reaction.

Oxygen reduction is a key reaction in many energy conversion devices. Phosphorus-containing porous organic polymers not only have developed pores and surface structure, but also have strong adjustable modification and modification, so they have a wide application prospect in heterogeneous catalysis. At present, the preparation of phosphorus-containing porous organic polymers and their applications in heterogeneous catalysis have not been reviewed. in this paper, the research progress in this field in the past decade is summarized and reviewed. The synthetic methods of phosphorus-containing porous organic polymers are developing rapidly, including coupling Polycondensation, lithium salt-mediated Polycondensation, Friedel-Crafts Polycondensation, solvothermal olefin polymerization, Scholl Polycondensation, phenolic polymerization, aldehyde-amine condensation, phosphorization of polypyran salts and multistage polymerization. At the same time of briefly describing the mechanism of oxygen reduction reaction, combined with the research results of my own team, this paper focuses on the application of new porous materials (metal-organic framework MOF, conjugated microporous polymer CMP, etc.) in electrocatalysis. In view of the problems existing in the current electrocatalysts, the future research ideas are pointed out, including the use of advanced technical means to characterize the active sites of the catalysts in situ, based on the fact that there are a large number of phosphine ligands in the framework, phosphorus-containing porous organic polymers can be loaded with a series of metal compounds to make supported metal nanoparticles catalysts, or even monoatomic or unit point metal catalysts. The optimal structure of the catalyst was inversely calculated from the high active sites, and the preparation conditions of the materials were optimized. Under the guidance of theory and practice, a new type of electrocatalyst with high efficiency, stability, economy and environmental protection was developed on the premise of in-depth understanding of the mechanism of oxygen reduction reaction. Then an example is given to introduce the use of POPs to solve the basic scientific problems related to biomimetic catalysis, and show its great application potential. Finally, the challenges and opportunities in this emerging field are summarized and put forward.

In the intestine, several phenols and aromatic acids are generated by microbiota and are highly related to the formation of uremic toxins. Herein, we developed a new derivatization reagent, 2-bromo-1-[4-(dimethylamino)phenyl] ethyl ketone (BDAPE), that reacted simultaneously with phenols and aromatic acids. Following a reaction within 2 h at 60 °C in the presence of 200 mM potassium carbonate (K2CO3), the obtained BDAPE derivatives were separated on a reversed-phase C18 column and quantified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) in positive electrospray ionization mode. This method allowed a lower limit of quantification (LLOQ) of 0.090 μΜ for 3-indolepropionic acid (3IPA), indole-3-acetic acid (3IAA), p-cresol (PC), benzoic acid (BA), and phenol (PN); 0.30 μΜ for phenylacetic acid (PAA); 0.45 μΜ for 4-hydroxyphenylacetic acid (4HPAA); and 0.60 μΜ for 3-phenylpropionic acid (PPA). Methodological validation further demonstrated acceptable accuracy (%RE

Rationale Short-chain fatty acids (SCFAs) are associated with intestinal microbiota and diseases in humans. SCFAs have a low response in mass spectrometry, and in order to increase sensitivity, reduce sample consumption, shorten analysis time, and simplify sample preparation steps, a derivatization method was developed. Methods We converted seven SCFAs into amide derivatives with 4-aminomethylquinoline. The reaction occurred for 20 min at room temperature. The analytes were separated on a reversed-phase C18 column and quantitated in the positive ion electrospray ionization mode using multiple reaction monitoring. Acetic acid-d4 was used as the stable-isotope-labeled surrogate analyte for acetic acid in the working solutions, while the other stable-isotope-labeled standards were used as internal standards (ISs). Results Method validation showed that the intra-day and inter-day precision of quantitation for the seven SCFAs over the whole concentration range was ≤3.8% (n = 6). The quantitation accuracy ranged from 85.5% to 104.3% (n = 6). Most important, the collected feces were vortexed immediately with ethanol. Conclusions This study provides a new derivatization method for a precise, accurate, and rapid quantitation of SCFAs in human feces using ultra-performance liquid chromatography/tandem mass spectrometry. This method successfully determined the concentration of SCFAs in human feces and could assist in the exploration of intestinal microbiota and diseases.

For improving the range accuracy of LFMCW Radar with triangle wave modulation, frequency estimation performance of Jacobsen algorithm and Quinn algorithm are discussed. When the signal frequency is close to the midpoint of two neighboring discrete frequencies, Jacobsen algorithm has poor accuracy, while Quinn algorithm has good one. A novel combined algorithm named J-Quinn algorithm is proposed. Firstly, Jacobsen algorithm is employed for coarse frequency estimation. Secondly, the signal frequency is shifted to the midpoint of two neighboring discrete frequencies, and then Quinn algorithm is employed for fine frequency estimation. The simulation shows that J-Quinn algorithm has higher range accuracy and good stability. Ranging experiments are performed with LFMCW Radar, and the results show that range error can be diminished to 0.04m, so the ranging performance is improved.

LFM signal is widely used in the domain of radar, sonar and communication. Both reliability and real-time is important for parameter estimation. The Fractional Fourier Transform exists problem of large calculation and bad real-time performance. To solve the problem, we use the Energy Barycenter Correction Method based on Nuttall window, combining with the idea of descending dimension. This method accomplish the task of turning two-dimensional search into one-dimensional search and get accurate estimates of frequency modulation ratio. At last, we use the method of the Fractional Fourier Transform to estimate Initial Frequency. So the real-time performance can be ensured, and the estimation accuracy can be improved. The simulation results show the validity and accuracy of the method, and the method has certain engineering application value.