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Phenyl polyenes comprise a small family of bacterial natural products with broad and potent bioactivities, primarily found in actinobacteria. Here we report the discovery of five new phenyl polyene metabolites, maduraflavacins A–E (1–5), from a rare, marine-derived actinobacteria strain Actinomadura glauciflavaNA03286. The structures of these natural products were determined by NMR spectroscopy, HRESIMS, LC-MS/MS, and chemical derivatization. All of these new maduraflavacins feature methyl substitutions at the polyene side chain, and maduraflavacins A–C (1–3) possessed a 1-N-β-d-glucosamine-(3 → 1)-O-β-d-glucopyranosyl-(3 → 1)-O-β-d-glucopyranosyl-(6 → 1)-O-β-d-glucopyranoside tetrasaccharide moiety via an amido linkage with a phenyl polyene skeleton. Compounds 1and 2showed weak antibacterial activities against the Gram-positive bacteria Staphylococcus aureusSau 16339 and Micrococcus luteus, respectively.

The interfacial solar steam generation for seawater desalination has attracted attention because of its excellent photothermal performance and efficiency. However, the process of preparing evaporators is often complex and costly, which limits their further practicality. Here, we report an integrated solar evaporator that is easy to prepare and has good salt resistance. The porous structure of poly(methyl methacrylate) and polycarbonate (PMMA–PC) films prepared by the breathing figure (BF) method was used as the upper layer, while MXene was deposited on the as-resulted PMMA–PC film and served as a light absorption layer. Meanwhile, the hydrophilicity of the lower layer of expanded polyethylene (EPE) foam can promote the upward transfer of water and inhibit heat loss. Under one solar irradiation, the water evaporation rate of the composite film was found to be 1.79 kg m–2h–1in distilled water and 1.67 kg m–2h–1in a 15 wt % NaCl solution, exhibiting excellent evaporation performance and salt resistance. In addition, the PMMA–PC/MXene films exhibit excellent mechanical properties. Based on these merits of the PMMA–PC/MXene solar generator, it may find useful applications in practical solar interfacial evaporation. Moreover, the findings of this investigation may provide a new opportunity for the rational design of large-aperture photothermal conversion materials via a simple breathing figure method.

With in-depth research on 1,2-difunctionalization, remote difunctionalization has garnered widespread attention for achieving multifunctionality. Herein, we report a strategy for achieving remote difunctionalization under mild conditions. This strategy exhibited good substrate suitability and functional group tolerance. In addition, the significance of this method is further evidenced by its successful application in scaling up and conducting additional transformations of target compounds. Mechanistic studies showed that a radical might be involved in this process.

We report a copper-catalyzed selective 1,2-phosphonoazidation of conjugated dienes. This three-component reaction is achieved by using readily available P(O)–H compounds and bench-stable NaN3. Salient features of this strategy include its mild reaction conditions, broad functional group tolerance, and high chemoselectivity and regioselectivity. Moreover, the compatibility with the late-stage functionalization of drug molecules, the potential for scalable production, and the feasibility of further modifications of the products underscore the practical utility of this protocol in synthetic applications.

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Composite phase change materials (PCMs) are of great importance for the storage and conversion of energy. In this study, a multishell metal oxide hollow microsphere (CuOHS) was prepared by the hydrothermal method, and a new composite PCM (CuOHS@PCMs) for energy storage and conversion purposes was developed by effectively absorbing fatty amines [namely, tetradecylamine (TDA), hexadecylamine (HDA), and octadecylamine (ODA)] PCMs into the CuOHS via the abundant micropores located on the surface of the microsphere. The incorporation of uncontaminated phase alteration substances with CuOHS yields superior light absorption and leak prevention traits. The three CuOHS@PCMs, specifically CuOHS@TDA, CuOHS@HDA, and CuOHS@ODA, possess considerable latent heats of 198.8, 192.6, and 196.0 J·g–1, respectively, and exhibit desirable thermal properties even after completing 50 and 100 thermal cycles. Moreover, under illumination, the photothermal conversion efficiencies of the three variations of CuOHS@PCMs were 84.0, 81.4, and 78.0%. This CuOHS@PCMs, which are based on CuOHS, have considerable potential in the fields of photothermal conversion, solar energy harvesting, and storage.

Solar-driven atmospheric water harvesting technology has the advantage of not being limited by geography and has great potential in solving the freshwater crisis. Here, we first propose a purely natural and degradable superhydrophilic composite macroporous hygroscopic material by applying guar gum (GG) to atmospheric water harvesting. The material consists of GG-cellulose nanofibers (CNFs) as a porous substrate material, limiting the hygroscopic factor lithium chloride (LiCl) in its three-dimensional (3D) network structure, and carbon nanotubes (CNTs) play a photothermal conversion role. The composite material has a high light absorption rate of more than 95%, and the macroporous structure (20–60 μm) allows for rapid adsorption/desorption kinetics. At 35 °C and 90% relative humidity (RH), the moisture absorption capacity is as high as 1.94 g/g. Under 100 mW/cm2irradiation, the absorbed water is almost completely desorbed within 3 h, and the water harvesting performance is stable in 10 cycles. Moreover, liquid water was successfully collected in an actual outdoor experiment. This work demonstrates the great potential of biomass materials in the field of atmospheric water collection and provides more opportunities for various energy and sustainable applications in the future.

Solar-driven interfacial evaporation co-generation (SIE-CG) technology is of great significance in solving the problem of water and energy shortage. Herein, we report the ionic liquid-assisted alignment of waste biomass tea residue-based microcrystalline cellulose for aerogels (abbreviated as TPPA-5) with aligned channels for solar-driven interfacial evaporation co-generation. In the ionic liquid, strong H-bonding is formed between the pyranoid rings of cellulose combined with the slow freezing technique, resulting in the microcrystalline cellulose being reoriented, which allowed TPPA-5 to form abundant aligned channels after solvent replacement and freeze-drying. These aligned channels enable the brine to form a localized circulating flow, which is conducive to the improvement of the TPPA’s evaporation rate and salt resistance. The salinity gradient is naturally formed in the channel of TPPA, which enables TPPA-5 to show excellent power generation performance. The evaporation rate of TPPA-5 can reach 3.39 kg m–2h–1under 1 kW m–2. With methanol as a highly polar proton solvent, the maximum output voltage obtained was 67.534 mV due to the overlapping electric double-layer effect formed by hydrogen protons on the TPPA surface, and the energy utilization efficiency is 95.95%. Moreover, TPPA-5 can purify pesticide-containing wastewater, which has the advantages of being recyclable and environmentally friendly, showing potential application value in the field of seawater desalination and steam co-generation.

Purpose: To evaluate the incidence of malignancies in acromegaly and to identify risk factors for newly-diagnostic cancers, especially the excessive growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Methods: A retrospective cohort including 1738 consecutive hospitalized patients with acromegaly in a single referral center between 2012 and 2020 (mean follow-up 4.3 years). A gender- and age-matched case-control study (280 patients from the cohort) was performed for risk factor analysis. Results: One hundred thirteen malignancies (67 diagnosed after acromegaly) were observed. The overall newly-diagnostic cancer risk of acromegaly was higher than the general population (standardized incidence ratio (SIR) 2.81; 95% CI 2.18–3.57). The risk of thyroid cancer (n= 33, SIR 21.42; 95% CI 13.74–30.08) and colorectal cancer (n= 8, SIR 3.17; 95% CI 1.37–6.25) was elevated. In the overall cohort, IGF-1 (ULN: 1.27 vs. 0.94, p= 0.057), GH (1.30 vs. 1.00 ng/ml, p= 0.12), and disease-controlled rate (34.9% vs. 45.9%, p= 0.203) at the last visit did not reach significance between patients with and without post-diagnostic cancer. In the case-control study, GH (1.80 vs. 0.90 ng/ml, p= 0.018) and IGF-1 (ULN: 1.27 vs. 0.91, p= 0.003) at the last visit were higher in patients with post-diagnostic cancers, with a lower disease-controlled rate. Elder age was a risk factor for cancer. Other metabolic comorbidities and the size of pituitary tumors were similar. Conclusion: The risk of malignancies, especially thyroid cancer, was increased in patients with acromegaly in our center. More cancer screening should be considered when managing acromegaly, especially in patients with higher posttreatment GH and IGF-1.

A visible-light-induced glycoarylation of activated olefins has been accomplished. Glycosyl radicals are generated via radical transfer strategies between (TMS)3SiOH and glycosyl bromides. Subsequent radical translocation and rapid 1,4-aryl migration form β-sugar amide derivatives, and eight types of sugars are compatible with this reaction. Further, the cascade reaction produced a quaternary carbon center with good functional group adaptability and high regioselectivity in mild conditions.

Metal–organic frameworks (MOFs) have become promising accommodation for enzyme immobilization in recent years. However, the microporous nature of MOFs affects the accessibility of large molecules, resulting in a significant decline in biocatalysis efficiency. Herein, a novel strategy is reported to construct macroporous MOFs by metal competitive coordination and oxidation with induced defect structure using a transition metal (Fe2+) as a functional site. The feasibility of in situ encapsulating β-glucosidase (β-G) within the developed macroporous MOFs endows an enzyme complex (β-G@MOF-Fe) with remarkably enhanced synergistic catalysis ability. The 24 h hydrolysis rate of β-G@MOF-Fe (with respect to cellobiose) is as high as approximately 99.8%, almost 32.2 times that of free β-G (3.1%). Especially, the macromolecular cellulose conversion rate of β-G@MOF-Fe reached 90% at 64 h, while that of β-G@MOFs (most micropores) was only 50%. This improvement resulting from the expansion of pores (significantly increased at 50–100 nm) can provide enough space for the hosted biomacromolecules and accelerate the diffusion rate of reactants. Furthermore, unexpectedly, the constructed β-G@MOF-Fe showed a superior heat resistance of up to 120 °C, attributing to the new strong coordination bond (Fe2+–N) formation through the metal competitive coordination. Therefore, this study offers new insights to solve the problem of the high-temperature macromolecular substrate encountered in the actual reaction.

Predicting interactions between metal–organic frameworks (MOFs) and their adsorbates based on structures is critical to design high-performance porous materials. Many gas uptake prediction models have been proposed, but adsorption isotherm prediction is still challenging for most existing models. Here, we report a deep learning approach (MOFNet) that can predict adsorption isotherms for MOFs based on hierarchical representation and pressure adaptive mechanism. We elaborately design a hierarchical representation to encode the MOF structures. We adopt a graph transformer network to capture atomic-level information, which can help learn chemical features required under low-pressure conditions. A pressure adaptive mechanism is employed to interpolate and extrapolate the given limited data points by transfer learning, which can predict adsorption isotherms on a wider pressure range by only one model. We demonstrate that our predictor outperformed other traditional machine learning as well as graph neural network models on the challenging benchmarks and also achieves high performance on the real-world experimental observed adsorption isotherms. Finally, we interpret the models to discover and present potential structure–property relationships using the self-attention mechanism in the network. The proof-of-concept applications, such as disordered MOF predictions and missing data imputation of gas adsorption isotherms, showcase the generality and usability of our model to improve MOF material design.

Acupuncture is used to relieve symptoms, reducing recurrence, and improve the lives of patients with skin diseases.

Herein, we describe the copper-catalyzed arylalkylation of activated alkenes via hydrogen-atom transfer and aryl migration strategy. The reaction was carried out through a radical-mediated continuous migration pathway using N-fluorosulfonamides as the alkyl source. The primary, secondary, and tertiary alkyl radicals formed by intramolecular hydrogen-atom transfer proceeded smoothly. This methodology is an efficient approach for the synthesis of various amide derivatives possessing a quaternary carbon center with good yields and high regioselectivity.

Aspergillus flavus(A. flavus) and its metabolites, aflatoxins, are widespread in crops and foods, threatening public health. Using chemical fungicides to control A. flavuscan pose safety hazards and cause environmental pollution. Therefore, there is an urgent need for safe and effective antifungal agents to control A. flavus. In this study, we isolated Aspergillus luchuensisYZ-1 cell-free supernatant (CFS), volatiles, and mycelial extracts to investigate their inhibitory effects on A. flavus. Results indicate that the CFS exhibited greater efficacy in impeding the growth and synthesis of aflatoxin B1 (AFB1) in A. flavus. Transcriptomic analysis revealed a significant downregulation of lipid metabolism, biosynthesis of other secondary metabolites, and glycan metabolism in A. flavustreated with CFS. Approximately 94% of the genes in the aflatoxin synthesis pathway were significantly downregulated. Furthermore, the CFS treatment significantly increased reactive oxygen species (ROS) production in A. flavus, affected its energy metabolism, and upregulated methane metabolism and the pentose phosphate pathway. We then investigated the inhibitory mechanism of YZ-1 against A. flavusby biochemical analysis. It was further confirmed that CFS had destructive effects in the cell wall and cell membrane of A. flavus, as indicated by leakage of nucleic acids, proteins, alkaline phosphatase (AKP), as well as decreased chitin and ergosterol content. In summary, this study provides novel insights into the mechanisms of CFS against A. flavus, suggesting its potential as a biocontrol agent in food and agriculture.

The first synthesis of highly strained spirocyclobutane-pyrrolines via a palladium-catalyzed tandem Narasaka–Heck/C(sp3or sp2)–H activation reaction is reported here. The key step in this transformation is the activation of a δ-C–H bond via an in situ generated σ-alkyl-Pd(II) species to form a five-membered spiro-palladacycle intermediate. The concerted metalation-deprotonation (CMD) process, rate-determining step, and energy barrier of the entire reaction were explored by density functional theory (DFT) calculations. Moreover, a series of control experiments was conducted to probe the rate-determining step and reversibility of the C(sp3)–H activation step.

Fungal symbionts co-evolve with hosts and microbial co-inhabitants to acquire an unpredictable potential for producing novel bioactive metabolites, but the knowledge about the topic remains patchy and superficial. Here we present the chemical characterization of acatulides A−G (1−7) as architecturally unprecedented macrolides from the solid-state culture of Acaulium albumH-JQSF, an arthropod-associated fungus. The acatulide structures were elucidated by spectroscopic analysis, modified Mosher's method and single-crystal X-ray diffraction. The plausible biosynthetic pathways for compounds 1−4are proposed. Interestingly, acatulides B−D (2−4) and G (7) were demonstrated to be neuroprotective against the 1-methyl-4-phenylpyridinium (MPP+)-induced damage to SH-SY5Y cells and nematode Caenorhabditis elegans(C. elegans).

This report describes the first application of a cyclobutanol ring-opening procedure in the Catellani termination reaction, which includes two β-carbon elimination processes. This tandem reaction features mild conditions, high yields, good functional group tolerance, and a broad substrate scope. Meanwhile, four types of electrophiles (N-benzoyloxyamines, alkyl iodides, aryl bromides, and benzyl chlorides) are quite compatible with this termination reaction for the construction of various types of polysubstituted aromatic hydrocarbons.

The mangrove-derived endophytic fungus Peniophora incarnataZ4 produced seven new xanthone derivatives, including four new tetrahydroxanthones (1–4), one new chromone (5), one new xanthone (6), and one new xanthone dimer (7), together with one known compound, globosuxanthone B (8). Their structures were determined by an extensive analysis of 1D and 2D NMR, HRESIMS, ECD, and single-crystal X-ray diffraction data. In cytotoxic activity assays, compound 2showed cytotoxicity against three carcinoma cell lines with IC50values less than 10 μM.

Genome mining of an indolocarbazole-type gene cluster from a marine-derived Nocardiopsis flavescensNA01583 strain led to the discovery of three new indolocarbazole alkaloids (1–3). Heterologous expression of the intact loogene cluster in a surrogate host Streptomyces lividansK4–114 led to the successful production of 3. Notably, compound 1showed potent cytotoxic activities toward eight cancer cell lines with IC50values ranging from 41 to 283 nM.

Pyranoanthocyanins are the important color and functional compounds in red wine. Six common kinds of pyranoanthocyanins were synthesized through the reaction of malvidin-3-O-glucoside (Mv-3-gluc) with acetone, pyruvic acid, p-cumaric acid, caffeic acid, ferulic acid, and sinapid acid, respectively, and their pH (1.0–11.0), SO2(0–250 ppm), and thermo (50–98 °C) stabilities and antioxidant activities were comparatively studied. Results showed that the six pyranoanthocyanins all exhibited higher pH and SO2color stability than Mv-3-gluc, especially vitisin-A with a carboxy group on the D ring. The six pyranoanthocyanins also showed much more thermostability than Mv-3-gluc, especially methylpyranomv-3-gluc. The degradation kinetics of Mv-3-gluc and its derivatives all fitted to a first-order reaction. Moreover, pinotin-A with the o-dihydroxyl group on the E ring presented the strongest antioxidant capability, as evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and ferric ion reducing power (FRAP) assays. Additionally, the increase in the number of rings is beneficial to the improvement of the DPPH radical scavenging ability of anthocyanins.

High fructose intake promotes hepatic lipid accumulation. Pterostilbene, a natural analogue of resveratrol found in diet berries, exhibits a hepatoprotective property. Here, we studied the protection by pterostilbene against fructose-induced hepatic lipid accumulation and explored its possible mechanism. We observed a high expression of microRNA-34a (miR-34a, P< 0.05) and a low expression of its target, sirtuin1 (Sirt1, mRNA: P< 0.01; protein: P< 0.001), with the overactivation of downstream sterol regulatory element-binding protein-1 (SREBP-1) lipogenic pathway (nuclear SREBP-1 protein: P< 0.05; FASand SCD1mRNA: P< 0.01), in rat livers, as well as BRL-3A and HepG2 cells, stimulated by fructose. More interestingly, pterostilbene recovered the fructose-disturbed miR-34a expression (0.3–0.5-fold vs fructose control, P< 0.05), Sirt1 protein level (1.2- to 1.5-fold vs fructose control, P< 0.05), and SREBP-1 lipogenic pathway, resulting in significant amelioration of hepatocyte lipid accumulation in animal [hepatic triglyceride and total cholesterol (TG&TC) mg/g·wet tissue: 4.90 ± 0.19, 5.23 ± 0.16, 5.20 ± 0.29 vs fructose control 9.73 ± 1.06, P< 0.001; 3.18 ± 0.30, 3.31 ± 0.39, 3.37 ± 0.47 vs 5.67 ± 0.28, P< 0.001] and cell models (BRL-3A TG&TC mmol/g·protein: 0.123 ± 0.011 vs 0.177 ± 0.004, P< 0.001; 0.169 ± 0.011 vs 0.202 ± 0.008, P< 0.05; HepG2: 0.257 ± 0.005 vs 0.303 ± 0.016, P< 0.05; 0.143 ± 0.004 vs 0.201 ± 0.008, P< 0.001). These results provide the experimental evidence supporting the anti-lipogenic effect of pterostilbene against fructose-induced hepatic lipid accumulation via modulating the miR-34a/Sirt1/SREBP-1 pathway.

Bacterial aromatic polyketides are compounds with multiple aromatic rings synthesized by bacterial type II polyketide synthases (PKSs), some of which have been developed into clinical drugs. Compounds containing aromatic polyketides synthesized by hybrid type I and type II PKSs are extremely rare. Here, we report the discovery of a gene cluster encoding both modular type I and type II PKSs as well as KAS III through extensive bioinformatics analysis, leading to the characterization of the hybrid polyketide, spirocycline A. The structure of spirocycline A is rare among all aromatic polyketides, featuring a unique starter unit and four spirocycles and forming a dimer. Biosynthetic studies indicate that the starter unit of this molecule is synthesized by type I PKS in collaboration with two trans-acting ketoreductase (KR) and enoylreductase (ER). It is then transferred by KAS III to the type II PKS system, which synthesizes the tricyclic aromatic polyketide backbone. The subsequent formation of the spirocycle and dimerization are carried out by four redox enzymes encoded in the gene cluster. Overall, the discovery of spirocycline A provides a new approach for identifying novel aromatic polyketides and offers potential enzymatic tools for the bioengineering of these hybrid polyketides.

Pure phase change materials (PCMs) have limited photothermal conversion capabilities. To improve the photothermal conversion capability of PCMs, we developed composite phase change materials (FHS@PCMs) of sea urchin-like Fe3O4hollow spheres (FHS) loaded with fatty amines (hexadecylamine (HDA) and octadecylamine (ODA)). The material composition and the surface nano-raised structure of FHS enable FHS@PCMs to exhibit excellent light absorption (up to 90 %, without any additional modification) and thermal conductivity. Moreover, the internal hollow spherical structure would prevent the leakage of PCM during the phase change process. Interestingly, FHS and FHS@PCMs exhibit inherent superhydrophobic properties with a water contact angle greater than 150°, thus endowing them with self-cleaning properties. FHS possesses strong magnetic properties that aid in material collection. Furthermore, the prepared FHS@PCMs exhibited exceptional thermal properties. The latent heat of FHS@HDA and FHS@ODA was 139.21 J∙g−1and 140.13 J∙g−1, respectively. Additionally, FHS@PCMs maintained their excellent thermal properties even after 50 and 100 thermal cycles. Under one solar radiation, FHS@PCMs show a photothermal conversion efficiency of 89.63 % and 88.02 %, respectively. Taking of these advantages, the as-prepared composite phase change material may have significant potential in the fields of solar energy conversion and storage.

目的:对全球范围内放化疗所致恶心呕吐指南/专家共识中针灸推荐意见进行总结分析, 为放化疗后恶心呕吐针灸临床实践指南的研制提供依据.方法:系统检索7个数据库,7个指南库及4个行业学会网站.检索时限均为建库至2023年4月1日.由2名研究者独立筛选文献,提取资料后, 采用临床实践指南科学性,透明性,适用性的评级工具 (Scientific, Transparent and Applicable Rankings tool, STAR tool) 评价含针灸推荐意见指南/共识的质量, 并对指南/专家共识中的针灸推荐意见及其证据基础进行分析总结.结果:共纳入56篇放化疗后恶心呕吐防治相关指南/专家共识, 其中22篇指南/专家共识含有针灸推荐意见, 针灸相关推荐意见共34条 (27条推荐, 4条不推荐不反对, 3条反对) .STAR评价(1篇患者指南未进行评价)结果显示无一篇指南/专家共识质量为高, 95.24% (20/21) 指南/专家共识质量中等, 4.76% (1/21) 指南质量低.现有指南/专家共识虽涉及针灸的推荐意见数量可观, 但推荐的针灸治疗方案之间异质性较大, 且多数不描述针灸治疗方案细节如针灸操作,穴位选择,干预时间及介入时机等, 难以指导针灸临床实践.结论:迫切需要依据STAR工具条目研制放化疗后恶心呕吐针灸临床实践指南, 明确针灸方案细节, 提供规范化治疗方案, 以指导针灸临床实践.