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1.
Microb Cell Fact ; 23(1): 87, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515152

RESUMO

BACKGROUND: Natural tetramates are a family of hybrid polyketides bearing tetramic acid (pyrrolidine-2,4-dione) moiety exhibiting a broad range of bioactivities. Biosynthesis of tetramates in microorganisms is normally directed by hybrid polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) machineries, which form the tetramic acid ring by recruiting trans- or cis-acting thioesterase-like Dieckmann cyclase in bacteria. There are a group of tetramates with unique skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, which remain to be investigated for their biosynthetic logics. RESULTS: Herein, the tetramate type compounds bripiodionen (BPD) and its new analog, featuring the rare skeleton of 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione, were discovered from the sponge symbiotic bacterial Streptomyces reniochalinae LHW50302. Gene deletion and mutant complementation revealed the production of BPDs being correlated with a PKS-NRPS biosynthetic gene cluster (BGC), in which a Dieckmann cyclase gene bpdE was identified by sit-directed mutations. According to bioinformatic analysis, the tetramic acid moiety of BPDs should be formed on an atypical NRPS module constituted by two discrete proteins, including the C (condensation)-A (adenylation)-T (thiolation) domains of BpdC and the A-T domains of BpdD. Further site-directed mutagenetic analysis confirmed the natural silence of the A domain in BpdC and the functional necessities of the two T domains, therefore suggesting that an unusual aminoacyl transthiolation should occur between the T domains of two NRPS subunits. Additionally, characterization of a LuxR type regulator gene led to seven- to eight-fold increasement of BPDs production. The study presents the first biosynthesis case of the natural molecule with 3-(2H-pyran-2-ylidene)pyrrolidine-2,4-dione skeleton. Genomic mining using BpdD as probe reveals that the aminoacyl transthiolation between separate NRPS subunits should occur in a certain population of NRPSs in nature.


Assuntos
Vias Biossintéticas , Policetídeo Sintases , Pirrolidinonas , Policetídeo Sintases/metabolismo , Bactérias/metabolismo , Piranos/metabolismo , Esqueleto/metabolismo , Peptídeo Sintases/genética
2.
Phytochemistry ; 220: 114017, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342290

RESUMO

Marine sponges are well known as prolific producers of structurally diverse molecules with valuable pharmacological potential. As part of our ongoing program to discover bioactive compounds from marine sponges collected from the Xisha Islands in the South China Sea, a chemical study on the specimens of Hippospongia lachne was conducted. As a result, eight undescribed compounds, including four zwitterionic alkylpyridinium salts, hippospondines A-D (1-4), and four 3-alkylpyridine alkaloids, hippospondines E (5), F (6), and (±)-hippospondine G (7), were isolated from the marine sponge H. lachne, together with one known 3-alkylpyridine alkaloid (8). The undescribed structures were elucidated by HRESIMS, NMR, DP4+ and CP3 probability analysis, and the Snatzke's method. Hippospondines A-D (1-4) represent the rare example of inner salt type alkylpyridinium alkaloid with a farnesyl moiety. Compounds 1-3 and 8 were subjected to cytotoxic and lymphocyte proliferation assays. Compound 3 exhibited a weak promotion effect on the ConA-induced T lymphocyte proliferation.


Assuntos
Alcaloides , Antineoplásicos , Poríferos , Animais , Espectroscopia de Ressonância Magnética , Antineoplásicos/química , Alcaloides/química , China , Estrutura Molecular
3.
Int Immunopharmacol ; 129: 111576, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38350353

RESUMO

Cyanogramide (AC14), a novel alkaloid, isolated from the fermentation broth of the marine-derived Actinoalloteichus cyanogriseus. However, the exact role of AC14 in inflammatory bowel disease (IBD) is poorly understood. Our results demonstrated that AC14 exhibited significant inhibition of IL-6 release in THP-1 cells and a "Caco-2/THP-1" coculture system after stimulation with LPS for 24 h. However, no significant effect on TNF-α production was observed. Furthermore, in 2.5 % DSS-induced colitis mice, AC14 treatment led to improvement in body weight, colon length, and intestine mucosal barrier integrity. AC14 also suppressed serum IL-6 production and modulated dysregulated microbiota in the mice. Mechanistically, AC14 was found to inhibit the phosphorylation of Janus kinase (JAK) 2 and signal transducers and activators of transcription (STAT) 3, while simultaneously elevating the expression of suppressor of cytokine signaling (SOCS) 3, both in vivo and in vitro. These findings suggest that AC14 exerts its suppressive effects on IL-6 production in DSS-induced IBD mice through the JAK2-STAT3-SOCS3 signaling pathway. Our study highlights the potential of AC14 as a therapeutic agent for the treatment of IBD.


Assuntos
Alcaloides , Antineoplásicos , Doenças Inflamatórias Intestinais , Poríferos , Humanos , Camundongos , Animais , Interleucina-6/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Células CACO-2 , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/tratamento farmacológico , Janus Quinase 2/metabolismo , Poríferos/metabolismo , Alcaloides/uso terapêutico , Fator de Transcrição STAT3/metabolismo
4.
J Nat Prod ; 87(2): 396-403, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38330072

RESUMO

Six new sesquiterpene quinone/hydroquinone meroterpenoids, arenarialins A-F (1-6), were isolated from the marine sponge Dysidea arenaria collected from the South China Sea. Their chemical structures and absolute configurations were determined by HRMS and NMR data analyses coupled with DP4+ and ECD calculations. Arenarialin A (1) features an unprecedented tetracyclic 6/6/5/6 carbon skeleton, whereas arenarialins B-D (2-4) possess two rare secomeroterpene scaffolds. Arenarialins A-F showed inhibitory activity on the production of inflammatory cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages with arenarialin D regulating the NF-κB/MAPK signaling pathway.


Assuntos
Dysidea , Poríferos , Sesquiterpenos , Animais , Dysidea/química , Poríferos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Anti-Inflamatórios/farmacologia , NF-kappa B , Estrutura Molecular
5.
Biotechnol Adv ; 70: 108295, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38052345

RESUMO

Rare actinomycetes are highly valued as potential sources of novel bioactive secondary metabolites. Among these rare actinomycetes, the genus Saccharothrix is particularly noteworthy due to its ability to produce a diverse range of bioactive secondary metabolites. With the continuous sequencing of bacterial genomes and the rapid development of bioinformatics technologies, our knowledge of the secondary metabolic potential of Saccharothrix can become more comprehensive, but this space has not been reviewed or explored. This review presents a detailed overview of the chemical structures and bioactivities of 138 Saccharothrix-derived secondary metabolites, which are classified into five distinct groups based on their biosynthetic pathways. Furthermore, we delve into experimentally characterized biosynthetic pathways of nine bioactive metabolites. By utilizing a combination of cheminformatic and bioinformatic approaches, we attempted to establish connections between the metabolite families and the biosynthetic gene cluster families encoded by Saccharothrix strains. Our analysis provides a comprehensive perspective on the secondary metabolites that can be linked to corresponding BGCs and highlights the underexplored biosynthetic potential of Saccharothrix. This review also provides guidance for the targeted discovery and biosynthesis of novel natural products from Saccharothrix.


Assuntos
Actinobacteria , Actinobacteria/genética , Actinobacteria/metabolismo , Biologia Computacional , Metabolismo Secundário/genética , Família Multigênica
6.
Int J Clin Pharm ; 46(1): 90-100, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37817027

RESUMO

BACKGROUND: Various genetic and nongenetic variables influence the high on-treatment platelet reactivity (HTPR) in patients taking clopidogrel. AIM: This study aimed to develop a novel machine learning (ML) model to predict HTPR in Chinese patients after percutaneous coronary intervention (PCI). METHOD: This cohort study collected information on 507 patients taking clopidogrel. Data were randomly divided into a training set (90%) and a testing set (10%). Nine candidate Machine learning (ML) models and multiple logistic regression (LR) analysis were developed on the training set. Their performance was assessed according to the area under the receiver operating characteristic curve, precision, recall, F1 score, and accuracy on the test set. Model interpretations were generated using importance scores by transforming model variables into scaled features and representing in radar plots. Finally, we established a prediction platform for the prediction of HTPR. RESULTS: A total of 461 patients (HTPR rate: 19.52%) were enrolled in building the prediction model for HTPR. The XGBoost model had an optimized performance, with an AUC of 0.82, a precision of 0.80, a recall of 0.44, an F1 score of 0.57, and an accuracy of 0.87, which was superior to those of LR. Furthermore, the XGBoost method identified 7 main predictive variables. To facilitate the application of the model, we established an XGBoost prediction platform consisting of 7 variables and all variables for the HTPR prediction. CONCLUSION: A ML-based approach, such as XGBoost, showed optimum performance and might help predict HTPR on clopidogrel after PCI and guide clinical decision-making. Further validated studies will strengthen this finding.


Assuntos
Clopidogrel , População do Leste Asiático , Intervenção Coronária Percutânea , Humanos , Clopidogrel/farmacologia , Estudos de Coortes , Inibidores da Agregação Plaquetária/farmacologia , Aprendizado de Máquina
7.
J Interv Cardiol ; 2023: 4717271, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38028026

RESUMO

Background: Venous thromboembolism (VTE) is a common cardiovascular disease that seriously threatens human lives. Anticoagulant therapy is considered to be the cornerstone of VTE treatment. An increasing number of studies has been updated in the VTE anticoagulation field. However, no bibliometric analyses have assessed these publications comprehensively. Therefore, our study aimed to analyze the global status, hotspots, and trends of anticoagulant therapy for VTE. Methods: The relevant literature on VTE anticoagulation published between 2012 and 2021 was retrieved and collected from the Web of Science Core Collection database. VOSviewer, Cooccurrence Matrix Builder, gCLUTO, and some online visualization tools were adopted for bibliometric analysis. Results: A total of 15,152 related articles were retrieved. In recent years, the research output of VTE anticoagulation gradually increased. The United States was the most productive country. International cooperation is concentrated in North America and Europe; the most influential documents, journals, authors, and organizations were also from these two continents. Research hotspots mainly focus on clinical guidelines, VTE in special populations, non-vitamin K oral anticoagulants (NOACs), and parenteral anticoagulation. The research frontiers and trends include the assessment of NOACs and the antithrombotic management of VTE complicated with coronavirus disease 2019 (COVID-19). Conclusion: This bibliometric analysis provides a systematic overview of the VTE anticoagulation research, which will facilitate researchers to better understand the situation of VTE anticoagulation. Future studies should be dedicated to NOACs application and VTE-combined COVID-19 patients.


Assuntos
COVID-19 , Tromboembolia Venosa , Humanos , Administração Oral , Anticoagulantes/uso terapêutico , COVID-19/complicações , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/etiologia , Vitamina K/uso terapêutico , Bibliometria
8.
Mar Drugs ; 21(10)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37888442

RESUMO

Eight new scalarane sesterterpenes, phyllofenones F-M (1-8), together with two known analogues, carteriofenones B and A (9-10), were isolated from the marine sponge Phyllospongia foliascens collected from the South China Sea. The structures of these compounds were determined based on extensive spectroscopic and quantum chemical calculation analysis. The antibacterial and cytotoxic activity of these compounds was evaluated. Among them, only compounds 4 and 6 displayed weak inhibitory activity against Staphylococcus aureus and Escherichia coli, with MIC values of 16 µg/mL and 8 µg/mL, respectively. Compounds 1-10 exhibited cytotoxic activity against the HeLa, HCT-116, H460, and SW1990 cancer cell lines, with IC50 values ranging from 3.4 to 19.8 µM.


Assuntos
Antineoplásicos , Poríferos , Animais , Humanos , Sesterterpenos/química , Poríferos/química , Espectroscopia de Ressonância Magnética , Antineoplásicos/química , Células HeLa , Escherichia coli , Estrutura Molecular
9.
Trials ; 24(1): 623, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37779187

RESUMO

BACKGROUND: Atrial fibrillation (AF) is a common arrhythmia that requires anticoagulation therapy to prevent stroke. However, there is still a significant under-/over-treatment in stroke prevention for patients with AF. The adherence and the risk of bleeding associated with oral anticoagulation therapy (OACs) are major concerns. Shared decision-making (SDM) is an approach that involves patients and healthcare providers in making decisions about treatment options. This study aims to assess the effectiveness of a novel SDM tool for anticoagulation management in AF. METHODS: The study will be a prospective, cluster randomized controlled trial involving 440 patients with AF in 8 community health service centers (clusters) in Shanghai, China. The SDM group will receive anticoagulation management through the novel SDM tool, while the control group will receive standard care. The follow-up period will be at least 2 years. The primary outcome will be any bleeding event, while secondary outcomes include the accordance of stroke prophylaxis for AF according to the current guidelines, time in therapeutic range (TTR), the occurrences of major bleeding and thrombosis events, and patient knowledge, adherence, and satisfaction. DISCUSSION: This study will provide evidence of the effectiveness of shared decision-making in improving the appropriateness of OAC use in Chinese AF patients. The findings may inform the development of guidelines and policies for the management of AF and anticoagulation therapy in China and other countries. TRIAL REGISTRATION: ChiCTR ChiCTR2200062123. Registered on 23 July 2022.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/tratamento farmacológico , Anticoagulantes/efeitos adversos , Estudos Prospectivos , China , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/complicações , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Diabetes Metab Syndr Obes ; 16: 2733-2744, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37706215

RESUMO

Purpose: The aim of this study was to evaluate whether intervention by clinical pharmacists can improve blood glucose and lipid levels in diabetic patients with complex medical conditions. Methods: The retrospective database included 138 patients with diabetes who had presented with acute myocardial infarction (AMI) between January 2019 and October 2021. Blood glucose and lipid levels were measured within 12 weeks and 78 weeks of follow-up. Propensity score matching (PSM) was used to balance the confounding effects of patients' characteristics. Results: A total of 138 eligible patients were assigned to either the intervention group (n = 47) or the usual care group (n = 91). After the intervention, there were significant improvements in blood glucose (glycosylated hemoglobin-HbA1C % from 9.0 to 8.3; fasting blood glucose-FBG mmol/L from 11.3 to 7.1; postprandial blood glucose-PBG mmol/L from 17.0 to 12.1; p < 0.001) and lipid levels (total cholesterol-TC from 4.9 to 3.5, low-density lipoprotein cholesterol-LDL-C from 3.0 to 1.8, p < 0.001, mmol/L) in both follow-up periods. The blood glucose effects were most pronounced in the PBG control rate (76.9% vs 54.0%) before PSM, while HbA1C% and PBG control rate after PSM were significantly higher in the intervention group (HbA1C% rate: 65.6% vs 38.5%; PBG rate: 79.2% vs 45.8%; p < 0.05, intervention vs non-intervention). Subgroup analysis further confirmed the improvement of blood glucose and lipid mainly in patients with higher baseline FBG (≧10mmol/L) and moderate follow-up duration (4-12 weeks). Conclusion: The intervention of clinical pharmacists in multidisciplinary team can significantly improve blood glucose and lipid levels in complex type 2 diabetic patients, especially those with high baseline FBG and moderate follow-up durations.

11.
Eur J Clin Pharmacol ; 79(12): 1631-1639, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37755492

RESUMO

BACKGROUND: Direct oral anticoagulants (DOACs) are increasingly recommended over warfarin in stroke prevention for patients with non-valvular atrial fibrillation (AF). However, there is an important evidence gap in choosing the most appropriate DOAC for Chinese patients in clinical practice. METHODS: A multi-criteria decision analysis (MCDA) was adopted to build a scoring framework. Attributes and criteria were identified and determined by a scoping literature review, two rounds of Delphi surveys, and a consensus meeting. Weights of each attribute and criterion in the framework were determined using analytic hierarchy process (AHP). Evidence was collected based on the domestic or at least Asian data. Scoring methods for each criterion were developed depended on their characteristics and determined with an expert consensus meeting. Comprehensive scores of each DOAC were calculated based on the utility scores of each criterion and their corresponding weights. RESULTS: A total of 5 attributes, including safety, efficacy, costs/cost-effectiveness, suitability, and accessibility, were determined, and 16 criteria were under the 5 attributes. The safety and efficacy were ranked as the top two important attributes with the weights of 38.8% and 35.9%, respectively, while the suitability received the lowest weight of 7.9%. The comprehensive score for edoxaban was the highest (72.3), followed by dabigatran (49.7), rivaroxaban (37.9), and apixaban (35.8). CONCLUSIONS: This study provided a scoring framework developed for comprehensive evaluation of DOACs in China. The ranking of DOACs could help to support the decision-making in clinical practice. The framework could provide a reference for comprehensive evaluation of other drugs.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Anticoagulantes/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/tratamento farmacológico , Varfarina/uso terapêutico , Rivaroxabana/uso terapêutico , Dabigatrana/uso terapêutico , Piridonas/uso terapêutico , Administração Oral
12.
Org Lett ; 25(34): 6391-6395, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37610094

RESUMO

An unusual secomeroterpenoid, dysambiol (1), was isolated from a Dysidea sp. marine sponge collected from the South China Sea. Dysambiol features an unprecedented secomeroterpene scaffold with a rare lactone bridge. The structure of 1 was determined by extensive spectroscopic analysis, Mosher's method, and electronic circular dichroism calculation. Dysambiol displayed potent anti-inflammatory activity in LPS-induced Raw 264.7 macrophages by regulating the NF-κB/MPAK signaling pathway.


Assuntos
Dysidea , Poríferos , Animais , Anti-Inflamatórios/farmacologia , China , Dicroísmo Circular
13.
Synth Syst Biotechnol ; 8(3): 349-356, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37325182

RESUMO

The bacterial trialkyl-substituted aromatic polyketides are structurally featured with the unusual aromatic core in the middle of polyketide chain such as TM-123 (1), veramycin A (2), NFAT-133 (3) and benwamycin I (4), which were discovered from Streptomyces species and demonstrated with antidiabetic and immunosuppressant activities. Though the biosynthetic pathway of 1-3 was reported as a type I polyketide synthase (PKS), the PKS assembly line was interpreted inconsistently, and it remains a mystery how the compound 3 was generated. Herein, the PKS assembly logic of 1-4 was revised by site-mutagenetic analysis of the PKS dehydratase domains. Based on gene deletion and complementation, the putative P450 monooxygenase nftE1 and metallo-beta-lactamase (MBL) fold hydrolase nftF1 were verified as essential genes for the biosynthesis of 1-4. The absence of nftE1 led to abolishment of 1-4 and accumulation of new products (5-8). Structural elucidation reveals 5-8 as the non-aromatic analogs of 1, suggesting the NftE1-catalyzed aromatic core formation. Deletion of nftF1 resulted in disappearance of 3 and 4 with the compounds 1 and 2 unaffected. As a rare MBL-fold hydrolase from type I PKSs, NftF1 potentially generates the compound 3 through two strategies: catalyze premature chain-offloading as a trans-acting thioesterase or hydrolyze the lactone-bond of compound 1 as an esterase.

14.
J Nat Prod ; 86(7): 1708-1714, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37317791

RESUMO

Cyanogripeptides A-C (1-3), three new cyclolipopeptides with unusual ß-methyl-leucine residues, were identified from an Actinoalloteichus cyanogriseus LHW52806 using an LC-MS-guided strategy. The structures of compounds 1-3 were elucidated by 1D/2D NMR, HR-MS/MS, and the advanced Marfey's method. The absolute configuration of the ß-methyl-leucine residue was determined by a combination of stereoselective biosynthesis of (2S,3R)-ß-methyl-leucine, racemization to its epimer (2R,3R)-ß-methyl-leucine, and the advanced Marfey's method. The biosynthetic pathway of cyanogripeptides was deduced by analyzing the genome of A. cyanogriseus LHW52806. Compound 3 exhibited antibacterial activity against Helicobacter pylori G27, Helicobacter pylori 26695, and Mycolicibacterium smegmatis ATCC607 with MIC values of 32 µg/mL.


Assuntos
Actinobacteria , Actinomycetales , Cromatografia Líquida , Espectrometria de Massas em Tandem , Leucina , Estrutura Molecular
15.
Bioorg Chem ; 139: 106699, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37390633

RESUMO

A chemical investigation of the marine sponge Phakellia sp. from the South China Sea yielded five new cyclopeptides, phakellisins A-E (1-5). Structures of these compounds were determined by comprehensive analysis of 1D/2D NMR, HRESIMS/MS spectroscopic data and the advanced Marfey's method. All compounds were evaluated for their cytotoxic activity. Compound 1 showed a strong inhibitory activity against WSU-DLCL-2 cells with an IC50 value of 5.25 ± 0.2 µM by induction of G0/G1 cell cycle arrest and apoptosis.


Assuntos
Peptídeos Cíclicos , Poríferos , Animais , Cromatografia Líquida , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/química , Espectrometria de Massas em Tandem , Poríferos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
16.
J Nat Prod ; 86(7): 1754-1760, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37335557

RESUMO

Phyllospongianes A-E (1-5), five new scalarane derivatives featuring an unprecedented 6/6/6/5 tetracyclic dinorscalarane scaffold, along with the known probable biogenetic precursor, 12-deacetylscalaradial (6), were isolated from the marine sponge Phyllospongia foliascens. The structures of the isolated compounds were determined by analysis of spectroscopic data and electronic circular dichroism experiments. Compounds 1-5 are the first 6/6/6/5 tetracyclic scalarane derivatives to be reported within the scalarane family. Compounds 1, 2, and 4 exhibited antibacterial activity against Vibrio vulnificus, Vibrio parahemolyticus, Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis, and Pseudomonas aeruginosa with MIC values ranging from 1 to 8 µg/mL. Furthermore, compound 3 exhibited significant cytotoxic activity on MDA-MB-231, HepG2, C4-2-ENZ, MCF-7, H460, and HT-29 cancer cell lines with IC50 values in the range between 0.7 and 13.2 µM.


Assuntos
Antineoplásicos , Poríferos , Animais , Sesterterpenos/química , Poríferos/química , Antineoplásicos/química , Antibacterianos/farmacologia , Bacillus subtilis , Escherichia coli , Estrutura Molecular
17.
Z Naturforsch C J Biosci ; 78(9-10): 345-352, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37354002

RESUMO

A systematic chemical study of the secondary metabolites of the marine fungus, Penicillium chrysogenum (No. Y20-2), led to the isolation of 21 compounds, one of which is new (compound 3). The structures of the 21 compounds were determined by conducting extensive analysis of the spectroscopic data. The pro-angiogenic activity of each compound was evaluated using a zebrafish model. The results showed that compounds 7, 9, 16, and 17 had strong and dose-dependent pro-angiogenic effects, with compound 16 demonstrating the strongest pro-angiogenic activity, compounds 6, 12, 14, and 18 showing moderate activity, and compounds 8, 13, and 19 exhibiting relatively weak activity.


Assuntos
Penicillium chrysogenum , Penicillium , Animais , Penicillium chrysogenum/química , Penicillium chrysogenum/metabolismo , Peixe-Zebra , Penicillium/química , Estrutura Molecular
18.
Clin Appl Thromb Hemost ; 29: 10760296231179439, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37264798

RESUMO

INTRODUCTION: Off-label, under-, and overdosed direct oral anticoagulants (DOACs) are commonly prescribed to patients with atrial fibrillation (AF), but real-world evidence on their effectiveness and safety is limited. METHODS: MEDLINE, Embase, and Cochrane Library databases were systematically searched from 01 July 2020 to 28 February 2022 to update a previous systematic review with the same search strategy from the inception to 30 June 2020. Eligible studies were those that reported effectiveness (stroke/systemic embolism and myocardial infarction) or safety (gastrointestinal or major bleeding and death) outcomes of off-label doses of DOACs compared to on-label doses in AF patients. A random-effects meta-analysis was performed to estimate the pooled hazard ratio (HR) and 95% confidence interval (CI). Subgroup analyses were performed by specific DOACs and geographic regions. RESULTS: Twenty-two studies were included. Off-label, underdosed DOACs, compared to on-label doses, were not associated with an increased risk of stroke (HR 1.03, 95%CI: 0.88-1.17) but were associated with an increased risk of death (HR 1.26, 95%CI: 1.09-1.43). However, risk varied depending on the active ingredient. No other safety outcomes were associated with underdosed DOACs. No significant differences were observed by geographic regions. Compared to on-label DOACs, overdosing increased the risk of stroke (HR 1.17, 95%CI: 1.04-1.31), major bleeding (HR 1.18, 95%CI: 1.05-1.31), and death (HR 1.19, 95%CI: 1.03-1.35). Risk varied between geographical regions. CONCLUSIONS: Off-label underdoses, compared to on-label dosing of DOACs, did not increase the risk of stroke but did increase overall mortality. Overdosed DOACs, compared to on-label doses, were associated with an increased risk of stroke, major bleeding, and death. Future studies must examine these associations, focusing on specific active ingredients and geographic settings.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Anticoagulantes , Uso Off-Label , Acidente Vascular Cerebral/tratamento farmacológico , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Administração Oral
19.
J Agric Food Chem ; 71(19): 7459-7467, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37148255

RESUMO

The biosynthesis of antitumor oxazole-containing conglobatin is directed by a multienzyme assembly line of nonribosomal peptide synthetase (NRPS) and polyketide synthase (PKS), in which an uncanonical iterative-acting C-terminal thioesterase domain, Cong-TE, ligated two fully elongated chains/conglobatin monomers on the terminal acylcarrier protein and subsequently cyclized the resulting dimer to a C2-symmetric macrodiolide. Screening of the conglobatin producer for secondary metabolites led to the discovery of two new compounds conglactones A (1) and B (2), possessing inhibitory activities to phytopathogenic microorganisms and cancer cells, respectively. The compounds 1 and 2 feature the ester bond-linked hybrid structures consisting of an aromatic polyketide benwamycin I (3) and one (for 1)/two (for 2) molecules of the conglobatin monomer (5). Genetic mutational analysis revealed that the production of 1 and 2 was correlated with the biosynthetic pathways of 3 and 5. Biochemical analysis indicated that 1 and 2 were produced by Cong-TE from 3 and an N-acetylcysteamine thioester form of 5 (7). Furthermore, the substrate compatibility of Cong-TE was demonstrated by enzymatically generating a bunch of ester products from 7 and 43 exotic alcohols. This property of Cong-TE was further validated by producing 36 hybrid esters in the fermentation of conglobatin producer fed with nonindigenous alcohols. This work shows a prospect of developing Cong-TE for green synthesis of valuable oxazole-containing esters, thus complementing the environmentally unfriendly chemosynthesis strategies.


Assuntos
Policetídeo Sintases , Policetídeos , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Metabolismo Secundário , Oxazóis/química
20.
Clin Appl Thromb Hemost ; 29: 10760296231171082, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37094089

RESUMO

BACKGROUND: The accuracy of current prediction tools for venous thromboembolism (VTE) events following hernia surgery remains insufficient for individualized patient management strategies. To address this issue, we have developed a machine learning (ML)-based model to dynamically predict in-hospital VTE in Chinese patients after hernia surgery. METHODS: ML models for the prediction of postoperative VTE were trained on a cohort of 11 305 adult patients with hernia from the CHAT-1 trial, which included patients across 58 institutions in China. In data processing, data imputation was conducted using random forest (RF) algorithm, and balanced sampling was done by adaptive synthetic sampling algorithm. Data were split into a training cohort (80%) and internal validation cohort (20%) prior to oversampling. Clinical features available pre-operatively and postoperatively were separately selected using the Sequence Forward Selection algorithm. Nine-candidate ML models were applied to the pre-operative and combined datasets, and their performance was evaluated using various metrics, including area under the receiver operating characteristic curve (AUROC). Model interpretations were generated using importance scores, which were calculated by transforming model features into scaled variables and representing them in radar plots. RESULTS: The modeling cohort included 2856 patients, divided into 2536 cases for derivation and 320 cases for validation. Eleven pre-operative variables and 15 combined variables were explored as predictors related to in-hospital VTE. Acceptable-performing models for pre-operative data had an AUROC ≥ 0.60, including logistic regression, support vector machine with linear kernel (SVM_Linear), attentive interpretable Tabular learning (TabNet), and RF. For combined data, logistic regression, SVM_Linear, and TabNet had better performance, with an AUROC ≥ 0.65 for each model. Based on these models, 7 pre-operative predictors and 10 combined predictors were depicted in radar plots. CONCLUSIONS: A ML-based approach for the identification of in-hospital VTE events after hernia surgery is feasible. TabNet showed acceptable performance, and might be useful to guide clinical decision making and VTE prevention. Further validated study will strengthen this finding.


Assuntos
Hérnia Inguinal , Tromboembolia Venosa , Adulto , Humanos , Hérnia Inguinal/cirurgia , Algoritmos , Hospitais , Aprendizado de Máquina
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