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Herein, we report an efficient dearomative [3+2] cycloaddition reaction of 2-alkynyl pyridines with diarylcyclopropenones, leading to the synthesis of densely functionalized indolizinones in moderate to good yields under metal-free conditions.

The characteristics of the study population were described in Supplementary Table 1. Details of SNPs for urate, hand grip strength and ALM are shown in Supplementary Tables 2-5. Scatter plots, funnel plots and leave-one-out sensitivity analysis are presented in Supplementary Fig. 1-3.

Objective: The relationship between fat accumulation in visceral or subcutaneous tissue and bone mineral density (BMD) remains unclear. In this study, we aim to shed light on this relationship by examining a large, nationally representative population. Methods: A weighted multiple linear regression model was established to evaluate the relationship between visceral fat, subcutaneous fat and BMD. Additionally, the potential nonlinear relationship was explored using smooth curve fitting method. Results: A total of 10455 participants between the ages of 20 and 59 were included in this study. Various weighted multiple linear regression models revealed a negative correlation between lumbar BMD T-score and visceral mass index (VMI) and subcutaneous mass index (SMI). However, the association between VMI and lumbar BMD T-score was U-shaped when we did smooth curve fitting, and the inflection point of 0.304kg/m² was determined using a two-stage linear regression model. Conclusions: Subcutaneous fat and BMD T-score were found to have a negative association, and visceral fat and BMD T-score were discovered to have a U-shaped connection. It is the significance of taking body composition and weight control into account while treating and preventing osteoporosis.

Objective The association between segmental body composition and bone mineral density (BMD) is unclear. This study analyzed the representative adult sample from the US in order to evaluate the association between segmental body composition and BMD. Method Ten thousand and ninety-six people aged 20–59 from the National Health and Nutrition Examination Survey (NHANES) database participated in this cross-sectional study. Segmental body composition and total BMD were examined using weighted multivariate linear regression analysis. Additionally, a subgroup analysis was performed according to age and gender group. Result The fat proportion of each body region was negatively related to total BMD once confounding variables were taken into account, while the arm and leg showing the most significant negative correlation. Lean mass and BMD were positively correlated in each region. Similar results were observed in all hierarchical analyses. Conclusion In essence, we discovered that BMD in American individuals aged 20 to 59 was inversely linked with the percentage of fat mass in various body locations. The increase of lean mass in each region had a protective effect on bones. Segmental body composition analysis may be used to provide information for predicting the health status of bone.

Pd-catalyzed carbonylation, as an efficient synthetic approach for the installation of carbonyl groups in organic compounds, has been one of the most important research fields in the past decade. Although elegant reactions that allow highly selective carbonylations have been developed, straightforward routes with improved reaction activity and broader substrate scope remain long-term challenges for new practical applications. Here, we show a new type of synergistic Cu/Pd-catalyzed carbonylation reaction using alcohols and dioxgen as the carbonyl sources. A broad range of aryl iodides and alcohols are compatible with this protocol. The reaction is concise and practical due to the ready availability of the starting materials and the scalability of the reaction. In addition, the reaction affords lactones and lactams in an intermolecular fashion. Moreover, DFT calculations have been performed to study the detailed mechanisms.

A straightforward and novel controllable site-selective construction of 2- and 4-substituted pyrimido[1,2-b]indazole from 3-aminoindazoles and ynals has been developed. The high regioselectivity of this reaction could be easily switched by converting different catalytic systems. In this way, a series of 2- and 4-substituted pyrimido[1,2-b]indazole derivatives were obtained in moderate to good yields. In addition, the photophysical properties of compound 3a prepared by the present method were discussed.

A direct cascade cyclization of 3-aminoindazoles, ynals, and accessible chalcogens facilitated by visible light has been developed. A series of fluoroactive selenium/tellurium-substituted pyrimido[1,2

The innovative construction of novel

The innovative construction of novel N,O-bidentate ligands and N,O π-conjugated four-coordinate organoboron complexes represent a long-standing challenge for chemists. Here, we report an unprecedented and straightforward approach for the construction of N,O-bidentate ligands and their organoboron complexes via the merge of ring deconstruction with cycloaromatization of indolizines and cyclopropenones. Without any catalysts, our method is able to deliver a series of polyaryl 2-(pyridin-2-yl)phenol ligands, N,O π-conjugated organoboron (BF2 and BAr2) complexes with good functional-group compatibility which are difficult or even impossible to synthesize with previous methods. Importantly, the formed N,O-bidentate ligands were easy to scale up and derive with valuable drugs and active molecules. In addition, the photoluminescence measurements and the HOMO/LUMO gap have been investigated, the results have revealed that N,O π-conjugated tetracoordinate boron complexes display bright fluorescence, large Stokes shifts, and good quantum yields (Φlum = 0.15–0.45). The method proposed by the paper will inspire the development of various N,O-bidentate metal and boron complexes, which is expected to move the area of catalysis chemistry and material science forward.

A new and efficient strategy for enynes cyclization catalyzed by triflic acid has been described. Various valuable carbocycle-fused and heterocycle-fused ketones were easily accessed by the formation of new C–C and C–O bond under benign reaction conditions. This protocol also provides another opportunity to construct polycyclic single-nitrogen ketones via a cation-induced cascade cyclization of polyenynes. Furthermore, antiviral bioassays revealed that a few compounds exhibited good antiviral activity against tobacco mosaic virus at a concentration of 200 μg mL–1.

A straightforward and novel controllable site-selective construction of 2- and 4-substituted pyrimido[1,2

Chimeric antigen receptor (CAR) T cells have an unprecedented positive curative effect for hematological malignances. Most notably, cluster of differentiation 19 (CD19) CAR T-cell therapy for pediatric acute lymphoblastic leukemia is associated with a high complete remission rate and has aroused considerable attention in the medical field. However, it also causes a series of adverse reactions and increases the risk of recurrence. The present review examines the results of CD19 CAR T-cell therapy and lists its adverse effects. In addition, some of the mechanisms of recurrence are characterized and applicable strategies to address this challenging problem are proposed.

Network scanners, honeypots and network crawlers are developed to collect the data in Industrial Control System. However, each software or system lacks uniform management rules due to the different developers and development environments. It is urgent to develop a multi-task collaborative scheduling system for the data collection in Industrial Control System in order to make full use of existing hardware and software resources, save human resource costs, and improve the real-time and accuracy of data collection and fusion tasks. The paper proposes a heterogeneous inter-node communication architecture for industrial control data acquisition and researches the evaluation model of resource node and task. An urgent sorting scheduling algorithm and preemptive scheduling algorithm is proposed to solve the multidimensional scheduling requirements and real-time problems of industrial control data collection tasks.

Sirtuin1 (SIRT1) belongs to the mammalian sirtuin family and plays an important role in deacetylating histones and non-histones. SIRT1 is associated with tumor metastasis in several tumors. However, the effect of SIRT1 on the mechanism of metastasis in resistant esophageal cancer remains unclear. In this study, we demonstrated that increased migration and invasion in drug-resistant esophageal cancer cells (EC109/PTX, TE-1/PTX). Our experiments revealed that the selective SIRT1 inhibitor (EX527) significantly suppressed cells migrate and inhibited the occurrence of the epithelial-mesenchymal transition (EMT), thereby altering the invasiveness and metastatic potential of the esophageal cancer cell lines. In addition, we observed that the inhibition of SIRT1 could alter the expression of snail. In conclusion, these results indicate that SIRT1 may promote the transformation of tumor cells by inducing the EMT and may serve as a potential molecular target for the treatment of resistant esophageal cancer.