Tandem catalytic allylic C-H amination and asymmetric [2,3]-rearrangement via bimetallic relay catalysis.

A bimetallic relay catalysis protocol for tandem allylic C-H amination and asymmetric [2,3]-sigmatropic rearrangement has been developed with the use of an achiral Pd0 catalyst and a chiral N,N'-dioxide-MgII complex in a one-pot operation. A series of anti-α-amino derivatives containing two stereogenic centers were prepared from readily available allylbenzenes and glycine pyrazolamide with good yields and high stereoselectivities. Moreover, the synthetic potential of this protocol was further demonstrated by the product transformations, and a catalytic cycle was proposed to illustrate the reaction process.

[Development and characterization of tobacco suspension cell chassis NBS-1].

Plant synthetic biology has significant theoretical advantages in exploration and production of plant natural products. However, its contribution to the field of biosynthesis is currently limited due to the lack of efficient chassis systems and related enabling technologies. Synthetic biologists often avoid tobacco as a chassis system because of its long operation cycle, difficulties in genetic and metabolic modification, complex metabolism and purification background, nicotine toxicity, and challenges in accurately controlling for agricultural production. Nevertheless, the tobacco suspension cell chassis system offers a viable solution to these challenges. The objective of this research was to develop a tobacco suspension cell chassis with high scientific and industrial potential. This chassis should exhibit rapid growth, high biomass, excellent dispersion, high transformation efficiency, and minimal nicotine content. Nicotiana benthamiana, which has high applicability in molecular technology, was used to induce suspension cells. The induced suspension cells, named NBS-1, exhibited rapid growth, excellent dispersion, and high biomass, reaching a maximum biomass of 476.39 g/L (fresh weight), which was significantly higher than that of BY-2. The transformation efficiency of the widely utilized pEAQ-HT transient expression system in NBS-1 reached 81%, which was substantially elevated compared to BY-2. The metabolic characteristics and bias of BY-2 and NBS-1 were analyzed using transcriptome data. It was found that the gene expression of pathways related to biosynthesis of flavonoids and their derivatives in NBS-1 was significantly higher, while the pathways related to alkaloid biosynthesis were significantly lower compared to BY-2. These findings were further validated by the total content of flavonoid and alkaloid. In summary, our research demonstrates NBS-1 possesses minimal nicotine content and provides valuable guidance for selecting appropriate chassis for specific products. In conclusion, this study developed NBS-1, a tobacco suspension cell chassis with excellent growth and transformation, high flavonoid content and minimal nicotine content, which has important guiding significance for the development of tobacco suspension cell chassis.

Tandem gene duplication selected by activation of horizontally transferred gene in bacteria.

Horizontal gene transfer occurs frequently in bacteria, but the mechanism driving activation and optimization of the expression of horizontally transferred genes (HTGs) in new recipient strains is not clear. Our previous study found that spontaneous tandem DNA duplication resulted in rapid activation of HTGs. Here, we took advantage of this finding to develop a novel technique for tandem gene duplication, named tandem gene duplication selected by activation of horizontally transferred gene in bacteria (TDAH), in which tandem duplication was selected by the activation of horizontally transferred selectable marker gene. TDAH construction does not contain any reported functional elements based on homologous or site-specific recombination and DNA amplification. TDAH only contains an essential selectable marker for copy number selection and 9-bp-microhomology border sequences for precise illegitimate recombination. One transformation and 3 days were enough to produce a high-copy strain, so its procedure is simple and fast. Without subsequent knockout of the endogenous recombination system, TDAH could also generate the relatively stable high-copy tandem duplication for plasmid-carried and genome-integrated DNA. TDAH also showed an excellent capacity for increase gene expression and worked well in different industrial bacteria. We also applied TDAH to select the optimal high copy number of ribA for vitamin B2 production in E. coli; the yield was improved by 3.5 times and remained stable even after 12 subcultures. TDAH is a useful tool for recombinant protein production and expression optimization of biosynthetic pathways. KEY POINTS: • We develop a novel and efficient technique (TDAH) for tandem gene duplication in bacterium. TDAH is based on the mechanism of HTG rapid activation. TDAH does not contain any reported functional elements based on homologous recombination and DNA amplification. TDAH only contains an essential selectable marker for copy number selection, so its construction and procedure are very simple and fast. • TDAH is the first reported selected and stable tandem-gene-duplication technique in which the selected high-copy plasmid-carried and genome-integrated DNA could remain stable without the subsequent knockout of recombination system. • TDAH showed an excellent capacity for regulating gene expression and worked well in different industrial bacteria, indicating it is a useful tool for recombinant protein production and expression optimization of biosynthetic pathways. • TDAH was applied to select the optimal high copy number of ribA for vitamin B2 production in E. coli; the yield was improved by 3.5-fold and remained stable even after 12 subcultures.

An Exploration into the Fault Diagnosis of Analog Circuits Using Enhanced Golden Eagle Optimized 1D-Convolutional Neural Network (CNN) with a Time-Frequency Domain Input and Attention Mechanism.

With the continuous operation of analog circuits, the component degradation problem gradually comes to the forefront, which may lead to problems, such as circuit performance degradation, system stability reductions, and signal quality degradation, which could be particularly evident in increasingly complex electronic systems. At the same time, due to factors, such as continuous signal transformation, the fluctuation of component parameters, and the nonlinear characteristics of components, traditional fault localization methods are still facing significant challenges when dealing with large-scale complex circuit faults. Based on this, this paper proposes a fault-diagnosis method for analog circuits using the ECWGEO algorithm, an enhanced version of the GEO algorithm, to de-optimize the 1D-CNN with an attention mechanism to handle time-frequency fusion inputs. Firstly, a typical circuit-quad op-amp dual second-order filter circuit is selected to construct a fault-simulation model, and Monte Carlo analysis is used to obtain a large number of samples as the dataset of this study. Secondly, the 1D-CNN network structure is improved for the characteristics of the analog circuits themselves, and the time-frequency domain fusion input is implemented before inputting it into the network, while the attention mechanism is introduced into the network. Thirdly, instead of relying on traditional experience for network structure determination, this paper adopts a parameter-optimization algorithm for network structure optimization and improves the GEO algorithm according to the problem characteristics, which enhances the diversity of populations in the late stage of its search and accelerates the convergence speed. Finally, experiments are designed to compare the results in different dimensions, and the final proposed structure achieved a 98.93% classification accuracy, which is better than other methods.

Research on Denoising Method for Hydroelectric Unit Vibration Signal Based on ICEEMDAN-PE-SVD.

Vibration monitoring and analysis play a crucial role in the fault diagnosis of hydroelectric units. However, accurate extraction and identification of fault features from vibration signals are challenging because of noise interference. To address this issue, this study proposes a novel denoising method for vibration signals based on improved complementary ensemble empirical mode decomposition with adaptive noise (ICEEMDAN), permutation entropy (PE), and singular value decomposition (SVD). The proposed method is applied for the analysis of hydroelectric unit sway monitoring. Firstly, the ICEEMDAN method is employed to process the signal and obtain several intrinsic mode functions (IMFs), and then the PE values of each IMF are calculated. Subsequently, based on a predefined threshold of PE, appropriate IMFs are selected for reconstruction, achieving the first denoising effect. Then, the SVD is applied to the signal after the first denoising effect, resulting in the SVD spectrum. Finally, according to the principle of the SVD spectrum and the variation in the singular value and its energy value, the signal is reconstructed by choosing the appropriate reconstruction order to achieve the secondary noise reduction effect. In the simulation and case analysis, the method is better than the commonly used wavelet threshold, SVD, CEEMDAN-PE, and ICEEMDAN-PE, with a signal-to-noise ratio (SNR) improvement of 6.9870 dB, 4.6789 dB, 8.9871 dB, and 4.3762 dB, respectively, and where the root-mean-square error (RMSE) is reduced by 0.1426, 0.0824, 0.2093 and 0.0756, respectively, meaning that our method has a better denoising effect and provides a new way for denoising the vibration signal of hydropower units.

Zearalenone Exposure Disrupts STAT-ISG15 in Rat Colon: A Potential Linkage between Zearalenone and Inflammatory Bowel Disease.

Zearalenone (ZEN), a prevalent mycotoxin contaminating food and known for its intestinal toxicity, has been suggested as a potential risk factor for inflammatory bowel disease (IBD), although the exact relationship between ZEN exposure and IBD remains unclear. In this study, we established a rat model of colon toxicity induced by ZEN exposure to investigate the key targets of ZEN-induced colon toxicity and explore the underlying connection between ZEN exposure and IBD. Histological staining of the rat colon revealed significant pathological changes resulting from ZEN exposure (p < 0.01). Furthermore, the proteomic analysis demonstrated a notable upregulation of protein expression levels, specifically STAT2 (0.12 ± 0.0186), STAT6 (0.36 ± 0.0475) and ISG15 (0.43 ± 0.0226) in the rat colon (p < 0.05). Utilizing bioinformatics analysis, we combined ZEN exposure and IBD clinical sample databases to reveal that ZEN exposure may increase the risk of IBD through activation of the STAT-ISG15 pathway. This study identified novel targets for ZEN-induced intestinal toxicity, providing the basis for further study of ZEN exposure to IBD.

Photoredox-catalyzed diastereoselective dearomative prenylation and reverse-prenylation of electron-deficient indole derivatives.

Prenylated and reverse-prenylated indolines are privileged scaffolds in numerous naturally occurring indole alkaloids with a broad spectrum of important biological properties. Development of straightforward and stereoselective methods to enable the synthesis of structurally diverse prenylated and reverse-prenylated indoline derivatives is highly desirable and challenging. In this context, the most direct approaches to achieve this goal generally rely on transition-metal-catalyzed dearomative allylic alkylation of electron-rich indoles. However, the electron-deficient indoles are much less explored, probably due to their diminished nucleophilicity. Herein, a photoredox-catalyzed tandem Giese radical addition/Ireland-Claisen rearrangement is disclosed. Diastereoselective dearomative prenylation and reverse-prenylation of electron-deficient indoles proceed smoothly under mild conditions. An array of tertiary α-silylamines as radical precursors is readily incorporated in 2,3-disubstituted indolines with high functional compatibility and excellent diastereoselectivity (>20:1 d.r.). The corresponding transformations of the secondary α-silylamines provide the biologically important lactam-fused indolines in one-pot synthesis. Subsequently, a plausible photoredox pathway is proposed based on control experiments. The preliminary bioactivity study reveals a potential anticancer property of these structurally appealing indolines.

Circulating microRNAs as diagnostic biomarkers for melanoma: a systematic review and meta-analysis.

BACKGROUND: Recent studies have shown that circulating microRNAs (miRNAs) can be used as diagnostic biomarkers for melanoma. This study aimed to evaluate the diagnostic value of circulating miRNAs for melanoma. METHODS: A comprehensive literature search was conducted and the quality of the included literature was evaluated using QUADAS-2 (Quality Assessment for diagnostic accuracy studies), and the diagnostic accuracy was assessed by pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC). We used Deeks' funnel plot to evaluate publication bias. RESULTS: The meta-analysis included 10 articles covering 16 studies, and the results showed that circulating miRNAs provide high diagnostic accuracy for melanoma. The overall pooled sensitivity was 0.87 (95% CI: 0.82-0.91), specificity was 0.81 (95% CI: 0.77-0.85), PLR was 4.6 (95% CI: 3.7-5.8), NLR was 0.16 (95% CI: 0.11-0.23), DOR was 29 (95% CI: 18-49), and AUC was 0.90 (95% CI: 0.87-0.92), respectively. Subgroup analysis showed better diagnostic value in miRNA clusters, European population, plasma miRNAs, and upregulated miRNAs compared to other subgroups. CONCLUSIONS: The results indicated that circulating microRNAs can be used as a non-invasive biomarker for the diagnosis of melanoma.

[Pathogenesis of glucocorticoid-induced osteoporosis based on label-free mass proteomics].

OBJECTIVE: To explore pathogenesis of glucocortocoid-induced osteoporosis(GIOP) based on label-free mass proteomics. METHODS: Twevle female Sprague-Dawley(SD) rats were randomly divided into two groups, named as sham group and GIOP group. After one-week adaptive feeding, the rats of GIOP group were administered with dexamethasone via intramuscular injection according to 2.5 mg/kg weighting, while the rats of sham group were administered with the same amount of saline, twice a week. The tibias of each group were collected after 8-week modeling and made pathological sections to confirm the success of modeling. Three samples of each group were picked up to perform label-free mass proteomics. After quality control, differentially expressed proteins were identified according to qualitative and quantitative analyses. Then gene ontology(GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis, cluster analysis as well as protein-protein interaction analysis were performed using bioinformatics analysis. RESULTS: Compared with sham group, the structure of bone trabecular in GIOP group showed abnormal arrangement, uneven distribution and obvious fragmentation, which could demonstrate successful modeling. A total of 47 differentially expressed proteins (DEPs) were identified including 20 up-regulated and 27 down-regulated proteins. The expression of protein nucleophosmin 1(NPM1), adipocyte plasma membrane associated protein (APMAP), cytochromec oxidase subunit 6A1 (COX6A1) and tartrate-resistant acid phosphatase (ACP5) showed a significant difference between two groups. KEGG results showed DEPs were enriched on metabolism-related pathways, immune-related pathways and AMP-activated kinase (AMPK) signaling pathway. CONCLUSION: Protein NPM1, APMAP, COX6A1 and ACP5 showed a close relationship with pathogenesis of GIOP, which could serve as potential biomarkers of GIOP. AMPK signaling pathway played an important role in the occurrence and development of GIOP, which could be regarded as potential signaling pathway to treatment GIOP.

Enhancement Methods of Hydropower Unit Monitoring Data Quality Based on the Hierarchical Density-Based Spatial Clustering of Applications with a Noise-Wasserstein Slim Generative Adversarial Imputation Network with a Gradient Penalty.

In order to solve low-quality problems such as data anomalies and missing data in the condition monitoring data of hydropower units, this paper proposes a monitoring data quality enhancement method based on HDBSCAN-WSGAIN-GP, which improves the quality and usability of the condition monitoring data of hydropower units by combining the advantages of density clustering and a generative adversarial network. First, the monitoring data are grouped according to the density level by the HDBSCAN clustering method in combination with the working conditions, and the anomalies in this dataset are detected, recognized adaptively and cleaned. Further combining the superiority of the WSGAIN-GP model in data filling, the missing values in the cleaned data are automatically generated by the unsupervised learning of the features and the distribution of real monitoring data. The validation analysis is carried out by the online monitoring dataset of the actual operating units, and the comparison experiments show that the clustering contour coefficient (SCI) of the HDBSCAN-based anomaly detection model reaches 0.4935, which is higher than that of the other comparative models, indicating that the proposed model has superiority in distinguishing between the valid samples and anomalous samples. The probability density distribution of the data filling model based on WSGAIN-GP is similar to that of the measured data, and the KL dispersion, JS dispersion and Hellinger's distance of the distribution between the filled data and the original data are close to 0. Compared with the filling methods such as SGAIN, GAIN, KNN, etc., the effect of data filling with different missing rates is verified, and the RMSE error of data filling with WSGAIN-GP is lower than that of other comparative models. The WSGAIN-GP method has the lowest RMSE error under different missing rates, which proves that the proposed filling model has good accuracy and generalization, and the research results in this paper provide a high-quality data basis for the subsequent trend prediction and state warning.

ZeXie decoction alleviates non-alcoholic fatty liver disease in rats: the study of genes, lipids, and gut microbiotas.

Recently, with increasing awareness of health issues, non-alcoholic fatty liver disease (NAFLD) has become an epidemic attracting global attention. As a serious chronic disease, NAFLD is clinically managed with pharmacological interventions that are usually associated with poor long-term efficacy and adverse effects. In this scenario, traditional Chinese medicine (TCM) characterized by "multiple ingredients-multiple targets-multiple pathways" shows promise as a potential option to treat NAFLD. Zexie decoction (ZXD) is a classical TCM formula that possesses favorable lipid-lowering and anti-inflammatory activities. Accumulating evidence indicates that ZXD displays robust efficacy in treating NAFLD. The effectiveness of ZXD against NAFLD has been evaluated in our previous studies. This study further examines its probable mechanism of action in an in-depth manner using multi-omic analysis based on the gut-liver axis and sheds light on the potential relationship among genes, hepatic lipid metabolites, and gut microbiotas. Totally, 71 differentially expressed genes (34 upregulated and 37 downregulated genes), 31 differential lipid molecules (8 upregulated and 23 downregulated), and 56 differential gut microbiotas (37 upregulated and 19 downregulated) were identified in the ZXD-treated group rats compared with the negative control group rats. Of these, owing to their key role in the association analysis, g_Blautia, g_Romboutsia, and g_Lactobacillus were hypothesized to be crucial gut microbiotas in the ZXD-mediated treatment of NAFLD. These microbiotas were found to synergize with key genes, such as AKR1B8, CCN1, and TNKS2, and hepatic lipid metabolites, such as glycerophospholipid and sphingomyelin, which might play a therapeutic role by regulating fatty acid synthesis, correcting lipid metabolism disorder, or reducing the inflammatory response. Overall, the present study provides fresh insights into the ZXD-mediated treatment of NAFLD, which, in turn, is expected to give a push to the modernization of TCM.

Patients with melanoma treated with immune checkpoint inhibitors who had non-thyroid endocrine and skin immune-related adverse events have better prognosis: A systematic review and meta-analysis.

Background: Several studies have reported an association between the occurrence of immune-related adverse events (irAEs) and prognosis in patients with melanoma treated with immune checkpoint inhibitors (ICIs), but the results remain controversial. We conducted a systematic review and meta-analysis to investigate the association between irAEs and survival in patients with melanoma treated with ICIs. Methods: We searched the PubMed, Web of Science, and China National Knowledge Infrastructure databases through May 5, 2022 for clinical studies evaluating the association between irAEs and in melanoma patients treated with ICIs. Combined hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) were calculated using fixed- or random-effects models based on heterogeneity. Results: A total of 60 articles were included, with 16,520 patients. In patients with melanoma treated with ICIs, the occurrence of irAEs was significantly associated with better OS (HR, 0.58; 95% confidence interval [CI], 0.51-0.66; P<0.00001) and PFS (HR, 0.61; 95%CI, 0.51-0.72; P<0.00001). Endocrine irAEs (OS, HR, 0.81; 95%CI, 0.72-0.92; P=0.001; PFS: HR, 0.84; 95%CI, 0.73-0.96, P=0.009), skin irAEs (OS, HR, 0.59; 95%CI, 0.41-0.85; P=0.004; PFS: HR, 0.43; 95%CI, 0.36-0.52; P<0.00001), vitiligo (OS, HR, 0.22; 95%CI, 0.15-0.31; P<0.00001; PFS, HR, 0.33; 95%CI, 0.25-0.44; P<0.00001), and grade 1-2 irAEs (OS, HR, 0.67; 95%CI, 0.58-0.78; P<0.00001; PFS, HR, 0.62; 95%CI, 0.51-0.76; P<0.00001) showed similar results. However, thyroid, lung, gastrointestinal, liver, and grade 3-4 irAEs were not significantly associated with OS and PFS. The occurrence of non-thyroid endocrine irAEs was significantly associated with better OS (HR, 0.22; 95%CI, 0.15-0.31; P<0.00001). In patients with melanoma treated with anti-programmed cell death protein 1 (OS, HR, 0.61; 95%CI, 0.51-0.72; P<0.00001; PFS, HR, 0.59; 95%CI, 0.47-0.74; P<0.00001), the association between irAEs and clinical benefit was clearer than in patients treated with anti-cytotoxic T-lymphocyte-associated protein 4 (OS, HR, 0.68; 95%CI, 0.52-0.89; P=0.005; PFS, HR, 0.93; 95%CI, 0.49-1.78; P=0.83). Conclusion: Among patients with melanoma treated with ICIs, those who developed non-thyroid endocrine irAEs and cutaneous irAEs have better prognosis. This suggests that non-thyroid endocrine irAEs and cutaneous irAEs may be a prognostic biomarker for patients with melanoma treated with ICIs. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022338308.

Diastereo- and Enantioselective Construction of Vicinal All-Carbon Quaternary Stereocenters via Iridium/Europium Bimetallic Catalysis.

The diastereo- and enantioselective construction of vicinal all-carbon quaternary stereocenters is a formidable task. We here report a synergistic bimetallic catalysis via a chiral N,N'-dioxide-europium (Eu) complex and a phosphoramidite-iridium (Ir) catalyst for the asymmetric allylation of oxindole derivatives by using challenging trisubstituted allylic esters. The allylated products bearing vicinal all-carbon quaternary stereocenters were obtained with good diastereoselectivities (up to 20 : 1 dr) and excellent enantioselectivities (up to 99 % ee). Control experiments showed that the complementary diastereomers of the products were not accessible by the change of the stereochemistry of the chiral N,N'-dioxide ligand.

Total Flavonoids of Drynariae Rhizoma Improve Glucocorticoid-Induced Osteoporosis of Rats: UHPLC-MS-Based Qualitative Analysis, Network Pharmacology Strategy and Pharmacodynamic Validation.

Background: Glucocorticoid-induced osteoporosis (GIOP) is a common form of secondary osteoporosis caused by the protracted or a large dosage of glucocorticoids (GCs). Total flavonoids of Drynariae rhizoma (TFDR) have been widely used in treating postmenopausal osteoporosis (POP). However, their therapeutic effects and potential mechanism against GIOP have not been fully elucidated. Methods: Ultra-high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UHPLC-ESIQ-TOF-MS) experiments were performed for qualitative analysis. We performed hematoxylin-eosin (HE) staining and microcomputed tomography (micro-CT) analysis to detect the changes in bone microstructure. The changes in biochemical parameters in the serum samples were determined by performing an enzyme-linked immunosorbent assay (ELISA). The prediction results of network pharmacology were verified via quantitative real-time polymerase chain reaction (qRT-PCR) to elucidate the potential mechanism of TFDR against GIOP. Results: A total of 191 ingredients were identified in vitro and 48 ingredients in vivo. In the in-vivo experiment, the levels of the serum total cholesterol (TC), the serum triglyceride (TG), Leptin (LEP), osteocalcin (OC), osteoprotegerin (OPG), bone morphogenetic protein-2 (BMP-2), propeptide of type I procollagen (PINP), tartrate-resistant acid phosphatase (TRACP) and type-I collagen carboxy-terminal peptide (CTX-1) in the TFDR group significantly changed compared with those in the GIOP group. Moreover, the TFDR group showed an improvement in bone mineral density and bone microstructure. Based on the results of network pharmacology analysis, 67 core targets were selected to construct the network and perform PPI analysis as well as biological enrichment analysis. Five of the targets with high "degree value" had differential gene expression between groups using qRT-PCR. Conclusion: TFDR, which may play a crucial role between adipose metabolism and bone metabolism, may be a novel remedy for the prevention and clinical treatment of GIOP.

Zearalenone-14-Glucoside Is Hydrolyzed to Zearalenone by ß-Glucosidase in Extracellular Matrix to Exert Intracellular Toxicity in KGN Cells.

As one of the most important conjugated mycotoxins, zearalenone-14-glucoside (Z14G) has received widespread attention from researchers. Although the metabolism of Z14G in animals has been extensively studied, the intracellular toxicity and metabolic process of Z14G are not fully elucidated. In this study, the cytotoxicity of Z14G to human ovarian granulosa cells (KGN) and the metabolism of Z14G in KGN cells were determined. Furthermore, the experiments of co-administration of ß-glucosidase and pre-administered ß-glucosidase inhibitor (Conduritol B epoxide, CBE) were used to clarify the mechanism of Z14G toxicity release. Finally, the human colon adenocarcinoma cell (Caco-2) metabolism model was used to verify the toxicity release mechanism of Z14G. The results showed that the IC50 of Z14G for KGN cells was 420 µM, and the relative hydrolysis rate of Z14G on ZEN was 35% (25% extracellular and 10% intracellular in KGN cells). The results indicated that Z14G cannot enter cells, and Z14G is only hydrolyzed extracellularly to its prototype zearalenone (ZEN) by ß-glucosidase which can exert toxic effects in cells. In conclusion, this study demonstrated the cytotoxicity of Z14G and clarified the toxicity release mechanism of Z14G. Different from previous findings, our results showed that Z14G cannot enter cells but exerts cytotoxicity through deglycosylation. This study promotes the formulation of a risk assessment and legislation limit for ZEN and its metabolites.

Intelligent Optimization of Tower Crane Location and Layout Based on Firefly Algorithm.

The existing tower crane positioning layout mainly depends on the experience of construction personnel, and the best tower crane positioning can be found through a large number of manual data calculation. This manual method is time-consuming and impractical. In view of this, aiming at the current situation that building information modeling (BIM) software can only obtain the relative coordinates of components, this article puts forward the key technology of importing computer-aided design (CAD) graphics into geographic information system (GIS) software to automatically obtain the world coordinate information. By clarifying the transfer relationship between the component material supply point, the component initial positioning point, and the tower crane optional positioning point, as well as the cooperative relationship between each positioning point and the tower crane operation, the tower crane positioning optimization model is formed, and the firefly algorithm is used to automatically calculate and generate the best positioning layout method of the tower crane on the project site. In this study, the vertical transportation and positioning of components are studied, and intelligent construction is formed by integrating information technology. It can further enrich the functions of perception, analysis, decision-making, and optimization; realize the decision-making intelligence of industrial buildings; and achieve the organic unity of engineering construction execution system and decision-making command system.

Deciphering the chemical constituents of Shengjiang Xiexin decoction by ultrahigh-performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry and the impact of 20 characteristic components on multidrug resistance-associated protein 2 in the vesicular transport assay.

Shengjiang Xiexin decoction, a traditional Chinese medical formula, has been utilized to alleviate the delayed-onset diarrhea induced by irino tecan. However, the chemical constituents of this formula and the activities of its constituents remain unclear. In this study, ultrahigh-performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry was employed to comprehensively analyze the chemical constituents of Shengjiang Xiexin decoction. A total of 270 components, including flavonoids, coumarins, triterpenoids, alkaloids, diarylheptanoids and others, were identified or characterized. Multidrug resistance-associated protein 2 is an efflux transporter responsible for regulating drug absorption. A total of 20 characteristic components from the formula were selected to evaluate their effects on the function of multidrug resistance-associated protein 2 using the vesicular transport assay. Glycyrrhizic acid and glycyrrhetinic acid were identified as potential multidrug resistance-associated protein 2 inhibitors, while 9 flavonoid aglycones increased the uptake of the substrate [3 H]-estradiol 17-ß-glucuronide in the vesicles. This was the first systematic investigation of the chemical constituents from Shengjiang Xiexin decoction and the effect of its characteristic components on the transporter. The results offered a basis for further exploring the detoxification mechanisms of this formula and its interactions with other drugs.

Enantioselective construction of cis-hydroindole scaffolds via an asymmetric inverse-electron-demand Diels-Alder reaction: application to the formal total synthesis of (+)-minovincine.

cis-Hydroindole scaffolds widely exist in a large number of natural products, pharmaceuticals, and organocatalysts. Therefore, the development of efficient and enantioselective methods for the construction of cis-hydroindoles is of great interest and importance. Herein, a novel approach for the enantioselective synthesis of cis-hydroindole scaffolds has been realized through a chiral N,N'-dioxide/Mg(OTf)2 complex catalyzed asymmetric inverse-electron-demand Diels-Alder (IEDDA) reaction of 2-pyrones and cyclic enamines. A series of substituted cis-hydroindole derivatives bearing multiple contiguous stereocenters and functional groups were obtained in good to excellent yields and enantioselectivities (up to 99% yield, and 95% ee) under mild reaction conditions. Moreover, the enantioselective formal total synthesis of (+)-minovincine was concisely furnished with high efficiency and stereoselectivity to demonstrate the synthetic potential of this method.

Qualitative Analysis of Drug-Containing Plasma and its Application to Quantitative Analysis and Pharmacokinetic Study of Zexie Decoction Using UPLC-MS/MS.

ZeXie Decoction (ZXD) is one of the traditional Chinese medicine formulas (TCMFs) comprising Alisma orientalis (Sam.) Juzep. (ZX) and Atractylodes macrocephala Koidz. (BZ) in 5:2 ratios and is widely employed in clinical applications since ancient times. In this study, UHPLC-QE-Orbitrap-MS was used for qualitative analysis of ZXD in rats' plasma after a single oral dose of 750 mg/kg body weight. Afterward, UHPLC-Q-TRAP-MS/MS was used for simultaneous analysis of three bioactive chemical compounds including alisol A, alisol B, and alisol A 24-acetate in ZXD's ethanol extract. Subsequently, the pharmacokinetic profiles of the three analytes were investigated in rat plasma utilizing UHPLC-Q-TRAP-MS/MS. The multiple reaction monitoring (MRM) mode for the three analytes were at m/z 508.4→383.2 for alisol A, m/z 490.4→365.2 for alisol B, and m/z 550.4→515.5 for alisol A 24-acetate. The analysis method was validated in terms of its accuracy, stability, repeatability, linearity, spiked recovery and matrix effect. As a result, twenty-five chemical constituents of ZXD were putatively identified in plasma, and rapid, sensitive, and accurate methods were established for the quantitative analysis and pharmacokinetic study of ZXD. The findings of this study can provide a scientific base for further study of in vivo pharmacokinetics of TCMFs.

Bimetallic Palladium/Cobalt Catalysis for Enantioselective Allylic C-H Alkylation via a Transient Chiral Nucleophile Strategy.

An asymmetric allylic C-H functionalization has been developed by making use of transient chiral nucleophiles, as well as bimetallic synergistic catalysis with an achiral Pd0 catalyst and a chiral N,N'-dioxide-CoII complex. A variety of ß-ketoesters and N-Boc oxindoles coupled with allylbenzenes and aliphatic terminal alkenes were well tolerated, furnishing the desired allylic alkylation products in high yields (up to 99 %) with excellent regioselectivities and enantioselectivities (up to 99 % ee).