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1.
Int J Ophthalmol ; 17(3): 528-536, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721515

RESUMO

AIM: To evaluate the effectiveness and safety of early lens extraction during pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) compared to those of PPV with subsequent cataract surgery. METHODS: This multicenter randomized controlled trial was conducted in three Chinese hospitals on patients with PDR, aged >45y, with mild cataracts. The participants were randomly assigned to the combined (PPV combined with simultaneously cataract surgery, i.e., phacovitrectomy) or subsequent (PPV with subsequent cataract surgery 6mo later) group and followed up for 12mo. The primary outcome was the change in best-corrected visual acuity (BCVA) from baseline to 6mo, and the secondary outcomes included complication rates and medical expenses. RESULTS: In total, 129 patients with PDR were recruited and equally randomized (66 and 63 in the combined and subsequent groups respectively). The change in BCVA in the combined group [mean, 36.90 letters; 95% confidence interval (CI), 30.35-43.45] was significantly better (adjusted difference, 16.43; 95%CI, 8.77-24.08; P<0.001) than in the subsequent group (mean, 22.40 letters; 95%CI, 15.55-29.24) 6mo after the PPV, with no significant difference between the two groups at 12mo. The overall surgical risk of two sequential surgeries was significantly higher than that of the combined surgery for neovascular glaucoma (17.65% vs 3.77%, P=0.005). No significant differences were found in the photocoagulation spots, surgical time, and economic expenses between two groups. In the subsequent group, the duration of work incapacity (22.54±9.11d) was significantly longer (P<0.001) than that of the combined group (12.44±6.48d). CONCLUSION: PDR patients aged over 45y with mild cataract can also benefit from early lens extraction during PPV with gratifying effectiveness, safety and convenience, compared to sequential surgeries.

2.
J Agric Food Chem ; 72(13): 6988-6997, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38506764

RESUMO

Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv oryzae (Xoo) is extremely harmful to rice production. The traditional control approach is to use bactericides that target key bacterial growth factors, but the selection pressure on the pathogen makes resistant strains the dominant bacterial strains, leading to a decline in bactericidal efficacy. Type III secretion system (T3SS) is a conserved and critical virulence factor in most Gram-negative bacteria, and its expression or absence does not affect bacterial growth, rendering it an ideal target for creating drugs against Gram-negative pathogens. In this work, we synthesized a range of derivatives from cryptolepine and neocryptolepine. We found that compound Z-8 could inhibit the expression of Xoo T3SS-related genes without affecting the growth of bacteria. an in vivo bioassay showed that compound Z-8 could effectively reduce the hypersensitive response (HR) induced by Xoo in tobacco and reduce the pathogenicity of Xoo in rice. Furthermore, it exhibited synergy in control of bacterial leaf blight when combined with the quorum quenching bacterial F20.


Assuntos
Alcaloides , Alcaloides Indólicos , Oryza , Quinolinas , Xanthomonas , Oryza/genética , Sistemas de Secreção Tipo III/genética , Bactérias/metabolismo , Xanthomonas/genética , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
3.
Phys Chem Chem Phys ; 25(37): 25639-25653, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37721171

RESUMO

In the present study, synchrotron-based X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS) and X-ray excited optical luminescence (XEOL) have been used to investigate the induced defect states in metal oxide nanomaterials. Specifically, two synthesis approaches have been followed to develop unique nano-sized peanut-shaped (N-ZnO) nanostructures and micron-sized hexagonal rods (M-ZnO). XANES analysis at the Zn K-edge revealed the presence of defect states with a divalent oxidation state of zinc (Zn2+) in a tetrahedral structure. Furthermore, XAS measurements performed at the Zn L3,2-edge and O K-edge confirm higher oxygen-related defects in M-ZnO, while N-ZnO appeared to have a higher concentration of surface defects due to size confinement. Moreover, the in-line XEOL and time dependent-XEOL measurements exposed the radiative excitonic recombination phenomena occurring in the band-tailing region as a function of absorption length, X-ray energy excitation, and time. Based on the chronology developed in the defect state improvement, a possible energy band diagram is proposed to accurately locate the defect states in the two systems. Furthermore, the increased absorption intensity at the Zn L3,2-edge and the O K-edge under the UV lamp suggests delayed recombination of electrons and holes, highlighting their potential use as photo catalysts. The photocatalytic activity degrading the rhodamine B dye established M-ZnO as a superior catalyst with a rapid degradation rate and significant mineralization. Overall, this work provides valuable insights into ZnO defect states and provides a foundation for efficient advanced materials for environmental or other optoelectronic applications.

4.
J Am Chem Soc ; 145(32): 17995-18006, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37550082

RESUMO

The acidic oxygen evolution reaction (OER) has long been the bottleneck of proton exchange membrane water electrolyzers given its harsh oxidative and corrosive environments. Herein, we suggest an effective strategy to greatly enhance both the acidic OER activity and stability of Co3O4 spinel by atomic Ru selective substitution on the octahedral Co sites. The resulting highly symmetrical octahedral Ru-O-Co collaborative coordination with strong electron coupling effect enables the direct dioxygen radical coupling OER pathway. Indeed, both experiments and theoretical calculations reveal a thermodynamically breakthrough heterogeneous diatomic oxygen mechanism. Additionally, the active Ru-O-Co units are well-maintained upon the acidic OER thanks to the electron transfer from surrounding electron-enriched tetrahedral Co atoms via bridging oxygen bonds that suppresses the overoxidation and thus dissolution of active Ru and Co species. Consequently, the prepared catalyst, even with a low Ru mass loading of ca. 42.8 µg cm-2, exhibits an attractive acidic OER performance with a low overpotential of 200 mV and a low potential decay rate of 0.45 mV h-1 at 10 mA cm-2. Our work suggests an effective strategy to significantly enhance both the acidic OER activity and stability of low-cost electrocatalysts.

5.
Bioorg Chem ; 139: 106652, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37390632

RESUMO

Primary liver cancer is one of the most common malignant cancers of the digestive system that lacks effective chemotherapeutic drugs in clinical settings. Camptothecin (CPT) and its derivatives have been approved for cancer treatment; however, their application is limited by their systemic toxicity. For lead optimization in new drug discovery stages, fluorination is an effective and robust approach to increase the bioavailability and optimize the pharmacokinetics of candidate compounds, thereby improving their efficacy. To obtain new and highly active CPT derivatives, we designed, synthesized, and evaluated two new fluorinated CPT derivatives, 9-fluorocamptothecin (A1) and 7-ethyl-9-fluorocamptothecin (A2), in this study. In vitro, A1 and A2 exhibited more robust anti-tumor activity than topotecan (TPT) in various cancer cells, particularly hepatocellular carcinoma (HCC) cells. In vivo, A1 and A2 exhibited greater anti-tumor activity than TPT in both AKT/Met induced primary HCC mouse models and implanted HepG2 cell xenografts. Acute toxicity tests revealed that A1 and A2 were not lethal and did not cause significant body weight loss at high doses. Moreover, A1 and A2 exhibited no significant toxicity in the mouse liver, heart, lung, spleen, kidney, and hematopoietic systems at therapeutic doses. Mechanistically, A1 and A2 blocked HCC cell proliferation by inhibiting the enzymatic activity of Topo I, subsequently inducing DNA damage, cell cycle arrest, and apoptosis. In summary, our results indicate that fluorination improves the anti-tumor activity of CPT while decreasing its toxicity and highlight the application potential of fluorination products A1 and A2 in clinical settings.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , DNA Topoisomerases Tipo I/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Topotecan/farmacologia , Inibidores da Topoisomerase I/farmacologia , Inibidores da Topoisomerase I/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
6.
Small ; 19(32): e2300807, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37086117

RESUMO

Designing a facile strategy to prepare catalysts with highly active sites are challenging for large-scale implementation of electrochemical hydrogen production. Herein, a straightforward and eco-friendly method by high-energy mechanochemical ball milling for mass production of atomic Ru dispersive in defective MoS2 catalysts (Ru1 @D-MoS2 ) is developed. It is found that single atomic Ru doping induces the generation of S vacancies, which can break the electronic neutrality around Ru atoms, leading to an asymmetrical distribution of electrons. It is also demonstrated that the Ru1 @D-MoS2 exhibits superb alkaline hydrogen evolution enhancement, possibly attributing to this electronic asymmetry. The overpotential required to deliver a current density of 10 mA cm-2 is as low as 107 mV, which is much lower than that of commercial MoS2 (C-MoS2 , 364 mV). Further density functional theory (DFT) calculations also support that the vacancy-coupled single Ru enables much higher electronic distribution asymmetry degree, which could regulate the adsorption energy of intermediates, favoring the water dissociation and the adsorption/desorption of H*. Besides, the long-term stability test under 500 mA cm-2 further confirms the robust performance of Ru1 @D-MoS2 . Our strategy provides a promising and practical way towards large-scale preparation of advanced HER catalysts for commercial applications.

7.
Nanomaterials (Basel) ; 12(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35957004

RESUMO

The surface plasmonic resonance, surface wettability, and related mechanical nanohardness and of face-centered-cubic (fcc) chromium nitride (CrN) films have been successfully manipulated via the simple method of tuning nitrogen-containing gas with different nitrogen-to-argon ratios, varying from 3.5 (N35), to 4.0 (N40), to 4.5 (N45), which is directly proportional to argon. All of the obtained CrN films showed that the surface wettability was due to hydrophilicity. All of the characteristics were mainly confirmed and explained by using X-ray diffraction (XRD) patterns, including plan-view and cross-section SEM images, with calculations of the average grain size performed via histograms accompanied by different preferred grain orientations. In the present work, not only the surface plasmonic resonance, but also the surface wettability and the related mechanical nanohardness of CrN films were found to be tunable via a simple method of introducing adjustable nitrogen-reactive-containing gas during the deposition process, while the authors suggest that the crystal orientation transition from the (111) to the (200) crystalline plane changed significantly with the nitrogen-containing gas. So the transition of the preferred orientation of CrN's cubic close-packed from (111) to (200) varied at this composite, caused and found by the nitrogen-containing gas, which can be tuned by the nitrogen-to-argon ratio. The surface plasmonic resonance and photoluminescence quenching effects were coupled photon and electron oscillations, which could be observed, and which existed at the interface between the CrN and Au metals in the designed heterostructures.

8.
Int Immunopharmacol ; 111: 109114, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35933747

RESUMO

Intestinal ischemia/reperfusion (II/R) is a clinical event associated with high morbidity and mortality. AMP-activated protein kinase (AMPK), a central cellular energy sensor, is associated with oxidative stress and inflammation. However, whether the AMPK is involved in the II/R-induced intestinal injury and the underlying mechanism is yet to be elucidated. Propofol has a protective effect on organs; yet, its specific mechanism of action remains unclear. This study explored the role of the AMPK-Sirt1-autophagy pathway in intestinal injury, and whether propofol could reduce intestinal injury and investigated the mechanisms in a rat model of II/R injury as well as a cell model (IEC-6 cells) of hypoxia/reoxygenation (H/R). Propofol, AMPK agonist (AICAR) and AMPK inhibitor (Compound C) were then administered, respectively. The histopathological changes, cell viability and apoptosis were detected. Furthermore, the levels of proinflammatory factors, the activities of oxidative stress, diamine oxidase, and signaling pathway were also analyzed. The results demonstrated that the AMPK-Sirt1-autophagy pathway of intestine was activated after II/R or H/R. Propofol could further activate the pathway, which reduced intestinal injury, inhibited apoptosis, reversed inflammation and oxidative stress, and improved the 24-hour survival rate in II/R rats in vivo, and attenuated H/R-induced IEC-6 cell injury, oxidative stress, and apoptosis in vitro, as fine as changes in AICAR treatment. Compound C abrogated the protective effect of propofol on II/R and H/R-induced injury. These results suggested a crucial effect of AMPK on the mechanism of intestinal injury and might provide a new insight into the mechanism of propofol reducing II/R injury.


Assuntos
Enteropatias , Propofol , Traumatismo por Reperfusão , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Apoptose , Autofagia , Inflamação , Intestinos/patologia , Isquemia , Propofol/farmacologia , Propofol/uso terapêutico , Ratos , Traumatismo por Reperfusão/metabolismo , Sirtuína 1/metabolismo
9.
Oxid Med Cell Longev ; 2022: 8729398, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035210

RESUMO

Cerebral ischemia/reperfusion (I/R) injury is a clinical event associated with high morbidity and mortality. Neuroinflammation plays a crucial role in the pathogenesis of I/R-induced brain injury and cognitive decline. Low-density lipoprotein receptor-related protein-1 (LRP1) can exert strong neuroprotection in experimental intracerebral hemorrhage. However, whether LRP1 can confer neuroprotective effects after cerebral I/R is yet to be elucidated. The present study is aimed at investigating the effects of LRP1 activation on cerebral I/R injury and deducing the underlying mechanism involving TXNIP/NLRP3 signaling pathway. Cerebral I/R injury was induced in mice by bilateral common carotid artery occlusion. LPR1 ligand, apoE-mimic peptide COG1410, was administered intraperitoneally. To elucidate the underlying mechanism, overexpression of TXNIP was achieved via the hippocampal injection of AAV-TXNIP before COG1410 treatment. Neurobehavioral tests, brain water content, immunofluorescence, Western blot, enzyme-linked immunosorbent assay, HE, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining were performed. Our results showed that the expressions of endogenous LRP1, TXNIP, NLRP3, procaspase-1, and cleaved caspase-1 were increased after cerebral I/R. COG1410 significantly ameliorated cerebral I/R-induced neurobehavioral deficits, brain edema, histopathological damage, and poor survival rate. Interestingly, COG1410 inhibited microglia proinflammatory polarization and promoted anti-inflammatory polarization, decreased oxidative stress, attenuated apoptosis, and inhibited the expression of the TXNIP/NLRP3 signaling pathway. However, the benefits of COG1410 were abolished by TXNIP overexpression. Thus, our study suggested that LRP1 activation with COG1410 attenuated cerebral I/R injury at least partially related to modulating microglial polarization through TXNIP/NLRP3 signaling pathway in mice. Thus, COG1410 treatment might serve as a promising therapeutic approach in the management of cerebral I/R patients.


Assuntos
Isquemia Encefálica , Disfunção Cognitiva , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Estresse Oxidativo , Traumatismo por Reperfusão , Animais , Proteínas de Transporte , Caspase 1 , Disfunção Cognitiva/prevenção & controle , Inflamassomos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Doenças Neuroinflamatórias , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais , Tiorredoxinas
10.
Pest Manag Sci ; 78(10): 4361-4376, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35758905

RESUMO

BACKGROUND: The abuse of chemical fungicides not only leads to toxic residues and resistance in plant pathogenic fungi, but also causes environmental pollution and side effects on in humans and animals. Based on the antifungal activities of berberine, seven different types of berberine derivatives (A1-G1) were synthesized, and their antifungal activities against six plant pathogenic fungi were evaluated (Rhizoctonia solani, Botrytis cinerea, Fusarium graminearum, Phytophthora capsici, Sclerotinia sclerotiorum, and Magnaporthe oryzae). RESULTS: The results for antifungal activities in vitro showed that berberine derivative E1 displayed good antifungal activity against R. solani with a median effective concentration (EC50 ) of 1.77 µg ml-1 , and berberine derivatives F1 and G1 demonstrated broad-spectrum antifungal activities with EC50 values ranging from 4.43 to 42.23 µg ml-1 against six plant pathogenic fungi. Berberine derivatives (E2-E29, F2-F18, and G2-G9) were further synthesized to investigate the structure-activity relationship (SAR), and compound E20 displayed significant antifungal activity against R. solani with an EC50 value of 0.065 µg ml-1 . Preliminary mechanism studies showed that E20 could cause mycelial shrinkage, cell membrane damage, mitochondrial abnormalities and the accumulation of harmful reactive oxygen species, resulting in cell death in R. solani. Moreover, in vivo experimental results showed that the protective effect of E20 was 97.31% at 5 µg ml-1 , which was better than that of the positive control thifluzamide (50.13% at 5 µg ml-1 ). CONCLUSION: Berberine derivative E20 merits further development as a new drug candidate with selective and excellent antifungal activity against R. solani. © 2022 Society of Chemical Industry.


Assuntos
Berberina , Fungicidas Industriais , Phytophthora , Antifúngicos/química , Berberina/farmacologia , Fungos , Fungicidas Industriais/química , Humanos , Plantas/microbiologia , Relação Estrutura-Atividade
11.
Oxid Med Cell Longev ; 2022: 8645714, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571246

RESUMO

Sepsis-associated encephalopathy (SAE) is linked to increased morbidity and mortality rates in patients with sepsis. Increased cytokine production and neuronal apoptosis are implicated in the pathogenesis of the SAE. Neuroinflammation plays a major role in sepsis-induced brain injury. Thioredoxin-interacting protein (TXNIP), an inhibitor of thioredoxin, is associated with oxidative stress and inflammation. However, whether the TXNIP is involved in the sepsis-induced brain injury and the underlying mechanism is yet to be elucidated. Therefore, the present study was aimed at elucidating the effects of TXNIP knockdown on sepsis-induced brain injury and cognitive decline in mice. Lipopolysaccharide (LPS) was injected intraperitoneally to induce sepsis brain injury in mice. The virus-carrying control or TXNIP shRNA was injected into the lateral ventricle of the brain 4 weeks before the LPS treatment. The histological changes in the hippocampal tissues, encephaledema, and cognitive function were detected, respectively. Also, the 7-day survival rate was recorded. Furthermore, the alterations in microglial activity, oxidative response, proinflammatory factors, apoptosis, protein levels (TXNIP and NLRP3 inflammasome), and apoptosis were examined in the hippocampal tissues. The results demonstrated that the TXNIP and NLRP3 inflammasome expression levels were increased at 6, 12, and 24 h post-LPS injection. TXNIP knockdown dramatically ameliorated the 7-day survival rate, cognitive decline, brain damage, neuronal apoptosis, and the brain water content, inhibited the activation of microglia, downregulated the NLRP3/caspase-1 signaling pathway, and reduced the oxidative stress and the neuroinflammatory cytokine levels at 24 h post-LPS injection. These results suggested a crucial effect of TXNIP knockdown on the mechanism of brain injury and cognitive decline in sepsis mice via suppressing oxidative stress and neuroinflammation. Thus, TXNIP might be a potential therapeutic target for SAE patients.


Assuntos
Lesões Encefálicas , Disfunção Cognitiva , Sepse , Animais , Lesões Encefálicas/etiologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Citocinas/metabolismo , Humanos , Inflamassomos/metabolismo , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doenças Neuroinflamatórias , Estresse Oxidativo , Sepse/complicações , Tiorredoxinas/metabolismo
12.
Biochem Pharmacol ; 200: 115049, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35469784

RESUMO

A series of new 7-ethyl-10-fluoro-20-O-(cinnamic acid ester)-camptothecin derivatives were synthesized and evaluated for cytotoxicity against four human tumor cell lines including HepG2 (hepatocellular carcinoma), SW480 (colorectal cancer), A2780 (ovarian cancer), and Hucct1 (intrahepatic cholangiocarcinoma). The results of cytotoxic activities in vitro showed that most of the camptothecin derivatives harbor promising cytotoxic activity against tested tumor cell lines. Among them, compound XJS-11 exhibited broad-spectrum inhibitory activities against HepG2, SW480, A2780, and Hucct1 cell lines with IC50 values of 0.03, 0.09, 0.22, and 0.32 µM, respectively. Further investigation demonstrated that compound XJS-11 exhibited more effective growth inhibition against a variety of human hepatoma cells (Sk-hep-1, Hep3B and Huh7) and lower cytotoxicity against immortalized normal human liver cell line L02 than the positive control topotecan. Especially, XJS-11 showed higher selective toxicity in two kinds of human hepatoma cells and immortalized normal human liver cell line (IC50(L-02)/IC50(HepG2) = 113.20; IC50(L-02)/IC50(Hep3B) = 85.60) than topotecan (IC50(L-02)/IC50(HepG2) = 9.45; IC50(L-02)/IC50(Hep3B) = 8.52). Mechanistically, XJS-11 induced cell cycle arrest and cell apoptosis in HepG2 and Hep3B cells by inhibiting Top I activity in a manner similar to that of topotecan. Meanwhile, XJS-11 could attenuate the tumor growth in both xenograft and primary HCC mouse models. In addition, the acute toxicity assay showed that XJS-11 did not cause lethality or significant body weight loss with a single intraperitoneal dose at 100 mg/kg or with an intraperitoneal dose at 25 mg/kg for 7 days. Moreover, unlike topotecan, XJS-11 had no apparent toxicity to the mouse liver, kidney, and hemopoietic system of the C57BL/6 mice. Taken together, XJS-11 merits further development as a new generation of the camptothecin-derived drug candidate.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias Ovarianas , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Cinamatos , Ensaios de Seleção de Medicamentos Antitumorais , Ésteres , Feminino , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Inibidores da Topoisomerase I/farmacologia , Inibidores da Topoisomerase I/uso terapêutico , Topotecan/farmacologia
13.
Bioorg Chem ; 122: 105747, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35338969

RESUMO

Based on the structural skeleton of natural products boeravinones, two types of 6H-chromeno[3,4-b]quinoline derivatives were designed and synthesized by nitrogen atom substitution strategy. Then, their cytotoxic activities were evaluated against six human tumor cell lines including HepG2 (hepatocellular carcinoma), A2780 (ovarian cancer), Hela (cervical cancer), HCT116 (colorectal cancer), SW1990 (pancreatic cancer), and MCF7 (breast cancer). The results showed that compounds ZML-8 and ZML-14 exhibited robust inhibitory activities against HepG2 cells with IC50 values of 0.58 and 1.94 µM, respectively. In addition, ZML-8 and ZML-14 showed higher selectivity against HepG2 and L-02 cells than Topotecan. Mechanistically, ZML-8 and ZML-14 not only induced cell cycle arrest in the G2/M phase and cell apoptosis, but also dose-dependently inhibited topoisomerase I activity and induced DNA damage in HepG2 cells. Molecular docking showed that ZML-8 and ZML-14 could interact with topoisomerase I-DNA complex with a similar binding mode to Topotecan. Inhibitory activities of these two compounds on topoisomerase I were then confirmed in both cell-free systems and in whole-cell lysates. Taken together, compounds ZML-8 and ZML-14 merit further development as a new generation of non-camptothecin topoisomerase I inhibitors for the treatment of cancer.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Simulação de Acoplamento Molecular , Inibidores da Topoisomerase I , Inibidores da Topoisomerase II/farmacologia
14.
J Agric Food Chem ; 70(9): 2851-2863, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35226498

RESUMO

Based on the structural characteristics of the cryptolepine alkaloid, a series of new quindoline derivatives bearing various substituents were prepared and evaluated for their fungicidal and antibacterial activities. Bioassay results showed that compound D7 displayed superior in vitro fungicidal activities against Sclerotinia sclerotiorum, Botrytis cinerea, Fusarium graminearum, and Rhizoctonia solani with EC50 values of 0.780, 3.62, 1.59, and 2.85 µg/mL, respectively. Compound A7 showed apparent antibacterial activities toward Xanthomonas oryzae pv. oryzae with a minimum inhibitory concentration (MIC) value of 3.12 µg/mL. Significantly, in vivo antifungal activity suggested that the curative effect (98.3%) of compound D7 was comparable to that of the positive control azoxystrobin (96.7%) at 100 µg/mL. Preliminary mechanistic studies showed that compound D7 might cause mycelial abnormality of S. sclerotiorum, cell membrane breakage, accumulation of reactive oxygen species (ROS), and inhibition of sclerotia formation. Therefore, compound D7 could be a novel broad-spectrum fungicidal candidate against plant fungal diseases.


Assuntos
Fungicidas Industriais , Alcaloides Indólicos , Alcaloides , Antifúngicos/química , Fungicidas Industriais/química , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Indóis , Estrutura Molecular , Quinolinas , Relação Estrutura-Atividade
15.
Eur J Med Chem ; 227: 113937, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34710744

RESUMO

Evodiamine and rutaecarpine are two alkaloids isolated from traditional Chinese herbal medicine Evodia rutaecarpa, which have been reported to have various biological activities in past decades. To explore the potential applications for evodiamine and rutaecarpine alkaloids and their derivatives, various kinds of evodiamine and rutaecarpine derivatives were designed and synthesized. Their antifungal profile against six phytopathogenic fungi Rhizoctonia solani, Botrytis cinerea, Fusarium graminearum, Fusarium oxysporum, Sclerotinia sclerotiorum, and Magnaporthe oryzae were evaluated for the first time. Furthermore, a series of modified imidazole derivatives of rutaecarpine were synthesized to investigate the structure-activity relationship. The results of antifungal activities in vitro showed that imidazole derivative of rutaecarpine A1 exhibited broad-spectrum inhibitory activities against R. solani, B. cinerea, F. oxysporum, S. sclerotiorum, M. oryzae and F. graminearum with EC50 values of 1.97, 5.97, 12.72, 2.87 and 16.58 µg/mL, respectively. Preliminary mechanistic studies showed that compound A1 might cause mycelial abnormalities of S. sclerotiorum, mitochondrial distortion and swelling, and inhibition of sclerotia formation and germination. Moreover, the curative effects of compound A1 were 94.7%, 81.5%, 80.8%, 65.0% at 400, 200, 100, 50 µg/mL in vivo experiments, which was far more effective than the positive control azoxystrobin. Significantly, no phytotoxicity of compound A1 on oilseed rape leaves was observed obviously even at a high concentration of 400 µg/mL. Therefore, compound A1 is expected to be a novel leading structure for the development of new antifungal agents.


Assuntos
Antifúngicos/farmacologia , Desenho de Fármacos , Alcaloides Indólicos/farmacologia , Quinazolinas/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Ascomicetos/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fusarium/efeitos dos fármacos , Alcaloides Indólicos/síntese química , Alcaloides Indólicos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Quinazolinas/síntese química , Quinazolinas/química , Rhizoctonia/efeitos dos fármacos , Relação Estrutura-Atividade
16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 522-526, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891347

RESUMO

Recently, deep learning algorithms have been used widely in emotion recognition applications. However, it is difficult to detect human emotions in real-time due to constraints imposed by computing power and convergence latency. This paper proposes a real-time affective computing platform that integrates an AI System-on-Chip (SoC) design and multimodal signal processing systems composed of electroencephalogram (EEG), electrocardiogram (ECG), and photoplethysmogram (PPG) signals. To extract the emotional features of the EEG, ECG, and PPG signals, we used a short-time Fourier transform (STFT) for the EEG signal and direct extraction using the raw signals for the ECG and PPG signals. The long-term recurrent convolution networks (LRCN) classifier was implemented in an AI SoC design and divided emotions into three classes: happy, angry, and sad. The proposed LRCN classifier reached an average accuracy of 77.41% for cross-subject validation. The platform consists of wearable physiological sensors and multimodal signal processors integrated with the LRCN SoC design. The area of the core and total power consumption of the LRCN chip was 1.13 x 1.14 mm2 and 48.24 mW, respectively. The on-chip training processing time and real-time classification processing time are 5.5 µs and 1.9 µs per sample. The proposed platform displays the classification results of emotion calculation on the graphical user interface (GUI) every one second for real-time emotion monitoring.Clinical relevance- The on-chip training processing time and real-time emotion classification processing time are 5.5 µs and 1.9 µs per sample with EEG, ECG, and PPG signal based on the LRCN model.


Assuntos
Eletroencefalografia , Processamento de Sinais Assistido por Computador , Algoritmos , Inteligência Artificial , Emoções , Humanos
17.
J Agric Food Chem ; 69(48): 14467-14477, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34843231

RESUMO

Crop diseases caused by fungi threaten food security and exacerbate the food crisis. Inspired by the application of fungicide candidates from natural products in agrochemical discovery, a series of luotonin A derivatives were designed, synthesized, and evaluated for their antifungal activities against five plant fungi. Most of these compounds exhibited significant fungicidal activity against Botrytis cinerea in vitro with EC50 values less than 1 µg/mL. Among them, compounds w7, w8, w12, and w15 showed superior antifungal activity against B. cinerea with EC50 values of 0.036, 0.050, 0.042, and 0.048 µg/mL, respectively, which were more potent than boscalid (EC50 = 1.790 µg/mL). Preliminary mechanism studies revealed that compound w7 might pursue its antifungal activity by disrupting the fungal cell membrane and cell wall. Moreover, in vivo bioassay also indicated that compound w7 could be effective for the control of B. cinerea. The above results evidenced the potential of luotonin A derivatives as novel and promising candidate fungicides.


Assuntos
Antifúngicos , Fungicidas Industriais , Antifúngicos/farmacologia , Botrytis , Fungos , Fungicidas Industriais/farmacologia , Pirróis , Quinonas , Relação Estrutura-Atividade
18.
Chem Biodivers ; 18(12): e2100633, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34643056

RESUMO

The increasing resistance of plant diseases caused by phytopathogenic fungi highlights the need for highly effective and environmentally benign agents. The antifungal activities of Cnidium monnieri fruit extracts and five isolated compounds as well as structurally related coumarins against five plant pathogenic fungi were evaluated. The acetone extract, which contained the highest amount of five coumarins, showed strongest antifungal activity. Among the coumarin compounds, we found that 4-methoxycoumarin exhibited stronger and broader antifungal activity against five phytopathogenic fungi, and was more potent than osthol. Especially, it could significantly inhibit the growth of Rhizoctonia solani mycelium with an EC50 value of 21 µg mL-1 . Further studies showed that 4-methoxycoumarin affected the structure and function of peroxisomes, inhibited the ß-oxidation of fatty acids, decreased the production of ATP and acetyl coenzyme A, and then accumulated ROS by damaging MMP and the mitochondrial function to cause the cell death of R. solani mycelia. 4-Methoxycoumarin presented antifungal efficacy in a concentration- dependent manner in vivo and could be used to prevent the potato black scurf. This study laid the foundation for the future development of 4-methoxycournamin as an alternative and friendly biofungicide.


Assuntos
Antifúngicos/farmacologia , Cnidium/química , Cumarínicos/farmacologia , Frutas/química , Rhizoctonia/efeitos dos fármacos , Acetilcoenzima A/antagonistas & inibidores , Acetilcoenzima A/biossíntese , Trifosfato de Adenosina/antagonistas & inibidores , Trifosfato de Adenosina/biossíntese , Antifúngicos/química , Antifúngicos/isolamento & purificação , Cumarínicos/química , Cumarínicos/isolamento & purificação , Ácidos Graxos/antagonistas & inibidores , Ácidos Graxos/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Rhizoctonia/crescimento & desenvolvimento
19.
Int J Mol Sci ; 22(19)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34639194

RESUMO

Humulus lupulus Linn. is a traditional medicinal and edible plant with several biological properties. The aims of this work were: (1) to evaluate the in vitro antifungal activity of H. lupulus ethanolic extract; (2) to study the in vitro and in vivo antifungal activity of isoxanthohumol, an isoprene flavonoid from H. lupulus, against Botrytis cinerea; and (3) to explore the antifungal mechanism of isoxanthohumol on B. cinerea. The present data revealed that the ethanolic extract of H. lupulus exhibited moderate antifungal activity against the five tested phytopathogenic fungi in vitro, and isoxanthohumol showed highly significant antifungal activity against B. cinerea, with an EC50 value of 4.32 µg/mL. Meanwhile, it exhibited moderate to excellent protective and curative efficacies in vivo. The results of morphologic observation, RNA-seq, and physiological indicators revealed that the antifungal mechanism of isoxanthohumol is mainly related to metabolism; it affected the carbohydrate metabolic process, destroyed the tricarboxylic acid (TCA) cycle, and hindered the generation of ATP by inhibiting respiration. Further studies indicated that isoxanthohumol caused membrane lipid peroxidation, thus accelerating the death of B. cinerea. This study demonstrates that isoxanthohumol can be used as a potential botanical fungicide for the management of phytopathogenic fungi.


Assuntos
Trifosfato de Adenosina/metabolismo , Antifúngicos/farmacologia , Botrytis/efeitos dos fármacos , Humulus/química , Peroxidação de Lipídeos/efeitos dos fármacos , Xantonas/farmacologia , Botrytis/crescimento & desenvolvimento
20.
J Agric Food Chem ; 69(40): 11781-11793, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34582205

RESUMO

Plant pathogenic fungi seriously affect agricultural production and are difficult to control. The discovery of new leads based on natural products is an important way to innovate fungicides. In this study, 30 natural-product-based magnolol derivatives were synthesized and characterized on the basis of NMR and mass spectroscopy. Bioactivity tests on phytopathogenic fungi (Rhizoctonia solani, Fusarium graminearum, Botrytis cinerea, and Sclerotinia sclerotiorum) in vitro of these compounds were performed systematically. The results showed that 11 compounds were active against four kinds of phytopathogenic fungi with EC50 values in the range of 1.40-20.00 µg/mL, especially compound L5 that exhibited excellent antifungal properties against B. cinerea with an EC50 value of 2.86 µg/mL, approximately 2.8-fold more potent than magnolol (EC50 = 8.13 µg/mL). Moreover, compound L6 showed the highest antifungal activity against F. graminearum and Rhophitulus solani with EC50 values of 4.39 and 1.40 µg/mL, respectively, and compound L7 showed good antifungal activity against S. sclerotiorum. Then, an in vivo experiment of compound L5 against B. cinerea was further investigated in vivo using infected tomatoes (curative effect, 50/200 and 36%/100 µg/mL). The physiological and biochemical studies illustrated that the primary action mechanism of compound L5 on B. cinerea might change the mycelium morphology, increase cell membrane permeability, and destroy the function of mitochondria. Furthermore, structure-activity relationship (SAR) studies revealed that hydroxyl groups play a key role in antifungal activity. To sum up, this study provides a reference for understanding the application of magnolol-based antifungal agents in crop protection.


Assuntos
Antifúngicos , Fungicidas Industriais , Animais , Antifúngicos/farmacologia , Ascomicetos , Compostos de Bifenilo , Botrytis , Fungicidas Industriais/farmacologia , Fusarium , Lignanas , Estrutura Molecular , Rhizoctonia , Relação Estrutura-Atividade
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