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1.
Chem Biodivers ; : e202402114, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39340168

RESUMO

Two undescribed letendrones A-B (1-2), along with three known compounds, ZL-6 (3), dankasterone B (4) and minimoidione B (5) were isolated from the Aquilaria-derived fungus Letendraea helminthicola A820. The structures of 1 and 2 were established by analysis of spectroscopes including 1D/2D NMR, IR, UV, and HRESIMS. Among them, the configuration of 1 was further confirmed by single-crystal X-ray diffraction. Letendrones A and B were the new phenalenyl derivatives with radical form that were firstly found in nature. In addition, bioactivity of these compounds was evaluated and compounds 3-5 exhibited inhibitory activity against LPS-induced NO production in macrophages with IC50 values of 4.64, 13.90, and 34.07 µM. Furthermore, potential targets of the new compounds were analyzed by molecular docking in silico. As a result, compound 1 showed high binding with predicted 5-HT2c receptor (∆G=-8.2 kcal/mol) potentially associated with depression disease, and compound 2 showed significant connection with phosphodiesterase 3A (∆G=-9.4 kcal/mol) probably against cardiovascular disorders. Our findings firstly reported the high symmetry phenalenyl compounds from natural products which would provide a basis for further development and utilization of the secondary metabolites from the endophytic fungus Letendraea helminthicola A820.

2.
Chem Commun (Camb) ; 60(80): 11327-11330, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39297768

RESUMO

Herein, we have described a novel organocatalytic approach to access biologically important dihydropyridin-2-ones in a one-pot way with generally high yields (up to 99%) and excellent enantioselectivities (up to 99% ee). This reaction proceeded via a new dual activation mode, including in situ-generated α,ß-unsaturated acylazoliums and 4-dimethylaminopyridinium salts that underwent a Michael addition/1,4-H migration/lactamization sequence. The base-triggered 4-dimethylaminopyridinium ylide formation pathway over the competing substitution reaction pathway of vicinal haloamines is noteworthy.

3.
Genome Biol ; 25(1): 241, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39252099

RESUMO

Advances in single-cell transcriptomics provide an unprecedented opportunity to explore complex biological processes. However, computational methods for analyzing single-cell transcriptomics still have room for improvement especially in dimension reduction, cell clustering, and cell-cell communication inference. Herein, we propose a versatile method, named DcjComm, for comprehensive analysis of single-cell transcriptomics. DcjComm detects functional modules to explore expression patterns and performs dimension reduction and clustering to discover cellular identities by the non-negative matrix factorization-based joint learning model. DcjComm then infers cell-cell communication by integrating ligand-receptor pairs, transcription factors, and target genes. DcjComm demonstrates superior performance compared to state-of-the-art methods.


Assuntos
Comunicação Celular , Análise de Célula Única , Transcriptoma , Análise de Célula Única/métodos , Análise por Conglomerados , Perfilação da Expressão Gênica/métodos , Humanos , Biologia Computacional/métodos
4.
Int J Biol Macromol ; 280(Pt 2): 135746, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39293613

RESUMO

Type D trichothecene toxins represent a class of macrocyclic trichothecene toxins with significant cytotoxicities towards human and crops. These toxins can also be used as anti-tumor compounds by the combination of antibody-drug conjugate. Therefore, it is urgent to investigate the biosynthetic routine of type D trichothecene toxins and explore type D trichothecene toxin-resistant genes, in order to ameliorate the hazard of trichothecene toxins and to facilitate the heterologous expression of toxin-biosynthetic cluster. In this study, tri18 gene was firstly knocked out in Paramyrothecium roridum, leading to the complete absence of type D trichothecene toxin epiroridin E, which can be restored by the complement of tri18 gene. Additionally, the knockout of tri18 gene led to a significant reduction in the pathogenicity of P. roridum towards pumpkin. Meanwhile, the enzymatic properties of Tri18 protein towards trichothecene deoxynivalenol (DON) toxin were also characterized. Moreover, tri3 and tri17KR with broad spectrum toxin-resistance function within the tri cluster were initially discovered through heterologous expression in toxin-sensitive Saccharomyces cerevisiae. And this study provides innovative type D trichothecene toxin resistant enzymes, which can provides green platform for the production of type D trichothecene toxins, thus promoting the application of these toxins in biomedical field.

5.
J Org Chem ; 89(18): 13429-13437, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39225401

RESUMO

The addition of C-H bonds to isocyanates catalyzed by transition metals is a highly auspicious methodology for providing synthetically and biologically important amides. However, the substrates are limited to C(sp2)-H bonds. In this work, an efficient manganese(I)-catalyzed direct addition reaction of C(sp3)-H bonds of 8-methylquinolines to aryl isocyanates has been developed, leading to the synthesis of various α-quinolinyl amide compounds in moderate to high yields. The reaction has a broad range of substrates and a good functional group tolerance. A possible mechanism is proposed based on the experimental results.

6.
Int J Biol Macromol ; 279(Pt 2): 135191, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39216588

RESUMO

Lotus (Nelumbo nucifera), belonging to the family of Nelumbonaceae, is a beautiful aquatic perennial plant. It has been used as an ancient horticulture plant and famous agricultural crop for thousands of years. Modern phytochemical and pharmacological experiments have proved that polysaccharide is one of the most pivotal bioactive constituents of lotus. Hence, the systematic review covering the fundamental research advances and developing prospects of N. nucifera polysaccharides (NNPs) is an urgent demand to provide theoretical basis for their further research and application. The present review summarizes current emerging research progresses on the polysaccharides isolated from lotus, and it focuses on advanced extraction and purification methods, unique structural features, engaging biological activities, potential molecular mechanisms, as well as the relationship of structure and activity of NNPs. This review sheds light on the potential values of NNPs in affording functionally bioactive agents in food industry or therapeutically effective medicines for health care. In addition, this review will provide valuable insights for further commercial product development and promising industrial application of NNPs in both of the fundamental research communities and food or pharmaceutical industries in future.


Assuntos
Polissacarídeos , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Humanos , Lotus/química , Animais , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Relação Estrutura-Atividade
7.
J Colloid Interface Sci ; 673: 594-606, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38897061

RESUMO

Although therapeutic nanovaccines have made a mark in cancer immunotherapy, the shortcomings such as poor homing ability of lymph nodes (LNs), low antigen presentation efficiency and low antitumor efficacy have hindered their clinical transformation. Accordingly, we prepared advanced nanovaccines (CMB and CMC) by integrating carbon dots (CDs) with tumor-associated antigens (B16F10 and CT26). These nanovaccines could forwardly target tumors harbouring LNs, induce strong immunogenicity for activating cytotoxic T cells (CTLs), thereby readily eliminating tumor cells and suppressing primary/distal tumor growth. This work provides a promising therapeutic vaccination strategy to enhance cancer immunotherapy.


Assuntos
Antígenos de Neoplasias , Vacinas Anticâncer , Carbono , Pontos Quânticos , Carbono/química , Animais , Antígenos de Neoplasias/imunologia , Camundongos , Pontos Quânticos/química , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/química , Camundongos Endogâmicos C57BL , Imunoterapia/métodos , Linfócitos T Citotóxicos/imunologia , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Linhagem Celular Tumoral , Nanopartículas/química , Propriedades de Superfície
8.
Chemistry ; 30(43): e202401386, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38837287

RESUMO

Vinyl sulfones are crucial building blocks in synthetic chemistry and core structural units of pharmaceutically active molecules, thus extensive investigations have been conducted on the construction of these skeletons. In contrast to the classical synthetic approaches, the radical sulfonylation of alkynes for producing vinyl sulfones has garnered considerable interest because of its mild conditions and high efficiency. Radical sulfonation of alkynes typically begins with the sulfonyl radical attacking the alkynes, followed by further functionalization. Moreover, the association of metal-catalyst-free systems with multicomponent reactions (MCRs) offers an environmentally friendly pathway for efficiently constructing complex scaffolds from readily available partners. However, there is no comprehensive review summarizing the advancements in metal-catalyst-free multicomponent radical sulfonylation of alkynes. Hence, we provide a categorical overview based on the objects of sulfonylation of alkynes (hydrosulfonylation, carbosulfonylation, aminosulfonylation, oxysulfonylation, sulfosulfonylation, selenosulfonylation, and iodosulfonylation), along with interpretations of the reaction mechanisms.

9.
Sensors (Basel) ; 24(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38931787

RESUMO

Grating-type spectral imaging systems are frequently employed in scenes for high-resolution remote-sensing observations of the Earth. However, the entrance of the grating-type spectral imaging system is a slit or a pinhole. This structure relies on the push broom method, which presents a challenge in capturing spectral information of transiently changing targets. To address this issue, the IFU is used to slice the focal plane of the telescope system, thereby expanding the instantaneous field of view (IFOV) of the grating-type spectral imaging system. The aberrations introduced by the expansion of the single-slice field of view (FOV) of the IFU are corrected, and the conversion of the IFU's FOV from arcseconds to degrees is achieved. The design of a spectral imaging system based on an image-slicer IFU for remote sensing is finally completed. The system has a wavelength range of 1400 nm to 2000 nm, and a spectral resolution of better than 3 nm. Compared with the traditional grating-type spectral imaging system, its IFOV is expanded by a factor of four. And it allows for the capture of complete spectral information of transiently changing targets through a single exposure. The simulation results demonstrate that the system has good performance at each sub-slit, thereby validating the effectiveness and advantages of the proposed system for dynamic target capture in remote sensing.

10.
Int J Biol Macromol ; 271(Pt 1): 132539, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38777023

RESUMO

The deep-sea fungus Phomopsis lithocarpus FS508 produces tenellone-macrolide conjugated hetero-dimer lithocarpins A-G with anti-tumor activities. The deficiency of new intermolecular Diels-Alder (DA) enzymes hindered the development of new bioactive hetero-dimers. A novel single-function intermolecular DA enzyme, g7882, was initially discovered in this study. The deletion of g7882 led to the disappearance of lithocarpin A and an increase in precursor level . the overexpression of g7882 significantly improved lithocarpin A yield. The in vitro function of g7882DA was also confirmed by biochemical reaction using tenellone B as a substrate. Additionally, the knockout of KS modules of PKS in cluster 41 and cluster 81 (lit cluster) eliminated the production of lithocarpins, which firstly explains the biosynthetic process of hetero-dimer lithocarpins mediated by DA enzyme in FS508. Furthermore, the removal of a novel acetyltransferase GPAT in cluster 41 and the oxidoreductase, prenyltransferase in cluster81 resulted in the reduction of lithocarpin A in P. lithocarpus. The overexpression of gpat in P. lithocarpus FS508 improved the yield of lithocarpin A significantly and produced a new tenellone derivative lithocarol G. This study offers a new DA enzyme tool for the biosynthesis of novel hetero-dimer and biochemical clues for the biosynthetic logic elucidation of lithocarpins.


Assuntos
Reação de Cicloadição , Ascomicetos/enzimologia , Família Multigênica
11.
Fitoterapia ; 175: 105931, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608733

RESUMO

Pararorine A, a new isoindolinone alkaloid was isolated from Paramyrothecium roridum, an endophytic fungus from the medicinal plant Gynochthodes officinalis (F.C. How) Razafim. & B. Bremer. The structure of this compound was elucidated by extensive spectroscopic (UV, IR, MS, and NMR) analyses. In addition, the antitumor activity of pararorine A was evaluated against SF-268, MCF-7, HepG2, and A549 tumor cell lines. The results revealed that pararorine A exhibited potent antitumor activities with the IC50 values ranging from 1.69 to 8.95 µM. Moreover, the tumor cell inhibitory activity of pararorine A was evidenced by promoting cytochrome C release and cell cycle arrest as well as the induction of apoptosis by the up-regulation of the protein expressions of JNK and Bax through PARP-cleavage and caspase 3-cleavage.


Assuntos
Apoptose , Humanos , Estrutura Molecular , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Endófitos/química , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Alcaloides/química , Antineoplásicos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , China
12.
Fitoterapia ; 175: 105952, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38614405

RESUMO

Three new xanthone derivatives irpexols A-C (1-3) and five known xanthones including three dimeric ones were successfully isolated from Irpex laceratus A878, an endophytic fungus of the family Irpicaceae from the medicinal plant Pogostemon cablin (Blanco) Bentham (Lamiaceae). The structures of these compounds were elucidated by extensive spectroscopic analyses including ultraviolet-visible spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS), and nuclear magnetic resonance (NMR). All of the three new compounds (1-3) share a de-aromatic and highly­oxygenated xanthone skeleton. In addition, the cytotoxic activity of compounds 1-8 were evaluated against SF-268, MCF-7, HepG2, and A549 tumor cell lines. The results revealed that compound 6 showed moderate cytotoxic activity with the IC50 values ranging from 24.83 to 45.46 µM, while the IC50 values of the positive control adriamycin was ranging from 1.11 to 1.44 µM.


Assuntos
Endófitos , Xantonas , Xantonas/isolamento & purificação , Xantonas/farmacologia , Xantonas/química , Estrutura Molecular , Humanos , Endófitos/química , Linhagem Celular Tumoral , Pogostemon/química , Antineoplásicos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/química , China
13.
Chem Commun (Camb) ; 60(38): 5066-5069, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38639013

RESUMO

The C-H bond activation catalyzed by a manganese(I) complex has achieved significant development but is limited to C(sp2)-H bonds. In this work, an efficient manganese(I)-catalyzed direct nucleophilic addition reaction of C(sp3)-H bonds to aromatic aldehydes has been developed. This is the first example of manganese(I)-catalyzed C(sp3)-H bond transformation. A manganacycle complex was isolated and proved to be the key active intermediate in the catalytic cycle.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38652581

RESUMO

The bromide-chloride mixed quasi-two-dimensional (2D) perovskite, with a natural quantum well structure and tunable exciton binding energy, has gained significant attention for high-performance blue perovskite light-emitting diodes (PeLEDs). However, the relative importance of having a low trap state density or efficient exciton transfer for high-efficiency electroluminescence (EL) performance remains elusive. Here, two molecules with the benzoic acid group, sodium 4-fluorobenzoate (SFB) and 3,5-dibromobenzoic acid (DBA), are used to modulate the phase distribution and trap state to explore the effect between energy transfer and defect passivation. As a result, when the n = 1 phase is inhibited in both films, the DBA@SFB-modified perovskite films achieve a higher photoluminescence quantum yield (PLQY) than the SFB-modified perovskite films due to effective defect passivation. However, DBA@SFB-modified PeLEDs exhibit lower external quantum efficiency (EQE) compared to SFB-modified PeLEDs due to the poor exciton transfer between the low-dimensional phase. This demonstrates that passivation strategies may enhance photoluminescence through reducing nonradiative recombination, but the effect of phase distribution is pivotal for EL performance by efficient energy transfer in quasi-2D perovskites. Femtosecond time-resolved transient absorption measurements confirm the fastest carrier dynamics in SFB-modified perovskite films, further corroborating the above result. This work provides useful information about phase modulation and defect passivation for high-efficiency blue quasi-2D PeLEDs.

15.
Compr Rev Food Sci Food Saf ; 23(1): e13273, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38284599

RESUMO

Rosemary (Rosmarinus officinalis L.) is one of the most famous spice plants belonging to the Lamiaceae family as a remarkably beautiful horticultural plant and economically agricultural crop. The essential oil of rosemary has been enthusiastically welcome in the whole world for hundreds of years. Now, it is wildly prevailing as a promising functional food additive for human health. More importantly, due to its significant aroma, food, and nutritional value, rosemary also plays an essential role in the food/feed additive and food packaging industries. Modern industrial development and fundamental scientific research have extensively revealed its unique phytochemical constituents with biologically meaningful activities, which closely related to diverse human health functions. In this review, we provide a comprehensively systematic perspective on rosemary by summarizing the structures of various pharmacological and nutritional components, biologically functional activities and their molecular regulatory networks required in food developments, and the recent advances in their applications in the food industry. Finally, the temporary limitations and future research trends regarding the development of rosemary components are also discussed and prospected. Hence, the review covering the fundamental research advances and developing prospects of rosemary is a desirable demand to facilitate their better understanding, and it will also serve as a reference to provide many insights for the future promotion of the research and development of functional foods related to rosemary.


Assuntos
Óleos Voláteis , Rosmarinus , Humanos , Extratos Vegetais/química , Rosmarinus/química , Aditivos Alimentares , Alimento Funcional , Óleos Voláteis/farmacologia , Plantas
16.
Eur J Epidemiol ; 39(2): 207-218, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38198037

RESUMO

The China Surgery and Anaesthesia Cohort (CSAC) study was launched in July 2020 and is an ongoing prospective cohort study recruiting patients aged 40-65 years who underwent elective surgeries with general anaesthesia across four medical centres in China. The general objective of the CSAC study is to improve our understanding of the complex interaction between environmental and genetic components as well as to determine their effects on a wide range of interested surgery/anaesthesia-related outcomes. To achieve this goal, we collected enriched phenotypic data, e.g., sociodemographic characteristics, lifestyle factors, perioperative neuropsychological changes, anaesthesia- and surgery-related complications, and medical conditions, at recruitment, as well as through both active (at 1, 3, 7 days and 1, 3, 6, 12 months after surgery) and passive (for more than 1 year after surgery) follow-up assessments. We also obtained omics data from blood samples. In addition, COVID-19-related information was collected from all participants since January 2023, immediately after COVID-19 restrictions were eased in China. As of July 18, 2023, 12,766 participants (mean age = 52.40 years, 57.93% were female) completed baseline data collection (response rate = 94.68%), among which approximately 70% donated blood and hair samples. The follow-up rates within 12 months after surgery were > 92%. Our initial analyses have demonstrated the incidence of and risk factors for chronic postsurgical pain (CPSP) and postoperative cognitive dysfunction (POCD) among middle-aged Chinese individuals, which may prompt further mechanistic exploration and facilitate the development of effective interventions for preventing those conditions. Additional studies, such as genome-wide association analyses for identifying the genetic determinants of CPSP and POCD, are ongoing, and their findings will be released in the future.


Assuntos
Anestesia , COVID-19 , Pessoa de Meia-Idade , Humanos , Feminino , Masculino , Estudo de Associação Genômica Ampla , Estudos Prospectivos , Anestesia/efeitos adversos , COVID-19/epidemiologia , China/epidemiologia
17.
Fitoterapia ; 173: 105751, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37977303

RESUMO

Three new α-pyrone derivatives cytospotones A-C (1-3) and a new cyclohexenone derivative cytospotone D (4) together with four known α-pyrones were isolated from the endophytic fungus Cytospora sp. A879 of Pogostemon cablin (Blanco) Benth. The structures of 1-4 were elucidated primarily by spectroscopic methods (1D, 2D NMR and HRESIMS), ECD spectra analyses, and ECD calculations. Furthermore, the four new compounds (1-4) were evaluated for their anti-inflammatory and α-glucosidase inhibitory activities. The results showed that compound 1 had moderate inhibitory effect on LPS-induced NO production in RAW 264.7 macrophages.


Assuntos
Ascomicetos , Pogostemon , Estrutura Molecular , Ascomicetos/química , Espectroscopia de Ressonância Magnética , Pironas
18.
Nat Prod Res ; 38(4): 594-600, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36938638

RESUMO

Two new compounds (R)-6-((8S)-hydroxypropyl)-2-methyl-5,6-dihydro-4H-pyran-4-one (1) and (R)-6-((8R)-hydroxypropyl)-2-methyl-5,6-dihydro-4H-pyran-4-one (2), together with four known compounds were isolated from the marine-derived fungus Cladosporium halotolerans FS702. The structures of these compounds were determined on the basis of extensive spectroscopic analysis including 1D/2D NMR, IR, UV, HRESIMS, ECD calculations as well as the modified Mosher's method. Cytotoxic assay results showed that compound 2 had significant cytotoxic activity against SF-268, MCF-7, HepG-2, and A549 cells lines with IC50 values of 0.16, 0.47, 0.33 and 0.23 µM, respectively.


Assuntos
Antineoplásicos , Pironas , Linhagem Celular Tumoral , Pironas/farmacologia , Antineoplásicos/química , Fungos/química , Cladosporium/química , Estrutura Molecular
19.
J Asian Nat Prod Res ; 26(4): 534-540, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37639617

RESUMO

Based on the One Strain-Many Compounds (OSMAC) strategy, the secondary metabolites of Phomopsis lithocarpus FS508 were investigated. As a result, a new secondary metabolite, 4-methoxy-3-[4-(acetyloxy)-3-methyl-2-butenyl]benzoic acid (1) as well as eleven known compounds were isolated from the fermentation product of the strain FS508. Their structures were determined by NMR, IR, UV, and MS spectroscopic data analyses. All the isolated compounds were evaluated for cytotoxic and anti-inflammatory activities. Among them, compounds 3 and 9 displayed potent cytotoxicity against HepG-2 cell line, and compounds 2, 3 and 12 showed significant anti-inflammatory activities.


Assuntos
Antineoplásicos , Ascomicetos , Phomopsis , Ascomicetos/química , Linhagem Celular Tumoral , Antineoplásicos/química , Anti-Inflamatórios/farmacologia , Estrutura Molecular
20.
Fitoterapia ; 172: 105772, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38064922

RESUMO

Three new compounds phomtersines A-C (1-3) together with nine known compounds were isolated from the marine-derived fungus Phomopsis tersa FS441. Their structures were sufficiently established by spectroscopic methods, including extensive 1D and 2D NMR techniques and modified Snatzke's method. Moreover, compounds 1-12 were evaluated for cytotoxic and anti-inflammatory activities. As a result, phomtersine B (2) and the known compound 10 showed moderate cytotoxic activity against the four tested cell lines with IC50 values ranging from 20.21 to 36.53 µM, and phomtersine A (1) exhibited moderate inhibitory activity against LPS-induced NO production.


Assuntos
Antineoplásicos , Ascomicetos , Linhagem Celular Tumoral , Estrutura Molecular , Ascomicetos/química , Antineoplásicos/farmacologia , Indóis/metabolismo
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