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1.
Nat Protoc ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514838

RESUMO

The synthesis of synthetic intracellular polymers offers groundbreaking possibilities in cellular biology and medical research, allowing for novel experiments in drug delivery, bioimaging and targeted cancer therapies. These macromolecules, composed of biocompatible monomers, are pivotal in manipulating cellular functions and pathways due to their bioavailability, cytocompatibility and distinct chemical properties. This protocol details two innovative methods for intracellular polymerization. The first one uses 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (Irgacure 2959) as a photoinitiator for free radical polymerization under UV light (365 nm, 5 mW/cm2). The second method employs photoinduced electron transfer-reversible addition-fragmentation chain-transfer polymerization with visible light (470 nm, 100 mW/cm2). We further elaborate on isolating these intracellular polymers by streptavidin/biotin interaction or immobilized metal ion affinity chromatography for polymers tagged with biotin or histidine. The entire process, from polymerization to isolation, takes ~48 h. Moreover, the intracellular polymers thus generated demonstrate significant potential in enhancing actin polymerization, in bioimaging applications and as a novel avenue in cancer treatment strategies. The protocol extends to animal models, providing a comprehensive approach from cellular to systemic applications. Users are advised to have a basic understanding of organic synthesis and cell biology techniques.

2.
Int J Biol Macromol ; 262(Pt 1): 130031, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331072

RESUMO

Plutella xylostella is an important cruciferous crop pest with a serious resistance to multiple insecticides, a novel natural compound, 2,3-dimethyl-6-(1-hydroxy)-pyrazine were isolated, that showed significant repellent activity against P. xylostella with olfactory system as a potential target. Eight odorant-binding proteins (OBPs) were determined as candidate target genes using RT-qPCR (Quantitative reverse transcription PCR), most of them were clustered with OBPs from Spodoptera frugiperda. Fluorescence competitive binding assays showed that PxylPBP2 (Pheromone binding protein) and PxylOBP3 had Ki values of 7.13 ± 0.41 µM and 9.56 ± 0.35 µM, indicating a high binding affinity to the pyrazine. Moreover, the binding style between these two OBPs and the pyrazine was determined as a hydrophobic interaction by using molecular docking. The binding between PxylPBP2 and the pyrazine was found to be more stable, and the carbon atoms of C-2 and C-3 in this pyrazine showed potential optimization characteristics. Both PxylPBP2 and PxylOBP3 were highly expressed in the antennae of both sexes. These results can be used to design and develop novel green pesticides with the pyrazine as the active or lead compound to reduce the utilization of chemical pesticides and postpone development of resistance.


Assuntos
Mariposas , Praguicidas , Receptores Odorantes , Feminino , Animais , Masculino , Simulação de Acoplamento Molecular , Odorantes , Pirazinas/farmacologia , Spodoptera/metabolismo , Praguicidas/metabolismo , Proteínas de Insetos/metabolismo , Receptores Odorantes/química , Mariposas/genética
3.
J Agric Food Chem ; 72(7): 3363-3373, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38324778

RESUMO

Cyantraniliprole is a novel insecticide recently introduced for rice pest control that may cause potential threats to the red swamp crayfish (Procambarus clarkii) in rice-crayfish coculture systems. In this study, we investigated the acute toxicity of cyantraniliprole against P. clarkii with a LC50 value of 149.77 mg/L (96 h), first. Some abnormal behaviors of P. clarkii treated with 125 mg/L cyantraniliprole, including incunabular hyperexcitability, imbalance, inactivity, and increased excretion were observed. Moreover, it was observed that exposure to 5 mg/L cyantraniliprole for 14 days resulted in histopathological alterations in abdominal muscle, gills, hepatopancreas, and intestines. Furthermore, exposure to 0.05 and 5 mg/L cyantraniliprole induced increased activities of several oxidative stress-related enzymes, which was verified by the upregulation of related genes. Additionally, dysregulation of the intestinal microbiota was determined via 16S rRNA sequencing. These results will provide the basis for the utilization of cyantraniliprole in the fields of rice-crayfish integrated system.


Assuntos
Microbioma Gastrointestinal , Oryza , Pirazóis , ortoaminobenzoatos , Animais , Astacoidea/genética , RNA Ribossômico 16S , Estresse Oxidativo
4.
J Agric Food Chem ; 72(1): 679-689, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38064576

RESUMO

This study systematically investigates the stereoselective metabolism and residue behavior of chiral pesticide prothioconazole enantiomers during the steaming, baking, and frying of steamed buns, bread, and deep-fried dough sticks. The results show that steaming, baking, and frying can significantly promote the degradation of the prothioconazole enantiomers. In low- and high-concentration treatments, the degradation rates of prothioconazole enantiomers were over 96.0% and 45.4%, respectively, and the residual concentration of prothioconazole-desthio enantiomers was less than 32.7 µg/kg (excluding fried processing). During the processing of steamed buns, bread, and deep-fried dough sticks, the enantiomer fraction (EF) value of the prothioconazole enantiomer was close to 0.5, and the stereoselectivity was not significant. During the processing of steamed buns (low concentration), bread (low and high concentrations), and deep-fried dough sticks (low concentration), the stereoselectivity of prothioconazole-desthio was significant, and preferential enantiomer degradation occurred. Following the analysis of 120 flour product samples, the residual risk.


Assuntos
Fungicidas Industriais , Praguicidas , Fungicidas Industriais/química , Farinha , Estereoisomerismo
5.
Chin J Integr Med ; 30(1): 25-33, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37750986

RESUMO

OBJECTIVE: To determine whether monotropein has an anticancer effect and explore its potential mechanisms against colorectal cancer (CRC) through network pharmacology and molecular docking combined with experimental verification. METHODS: Network pharmacology and molecular docking were used to predict potential targets of monotropein against CRC. Cell counting kit assay, plate monoclonal assay and microscopic observation were used to investigate the antiproliferative effects of monotropein on CRC cells HCT116, HT29 and LoVo. Flow cytometry and scratch assay were used to analyze apoptosis and cell cycle, as well as cell migration, respectively in HCT116, HT29, and LoVo cells. Western blotting was used to detect the expression of proteins related to apoptosis, cell cycle, and cell migration, and the expression of proteins key to the Akt pathway. RESULTS: The Gene Ontology and Reactome enrichment analyses indicated that the anticancer potential of monotropein against CRC might be involved in multiple cancer-related signaling pathways. Among these pathways, RAC-beta serine/threonine-protein kinase (Akt1, Akt2), cyclin-dependent kinase 6 (CDK6), matrix metalloproteinase-9 (MMP9), epidermal growth factor receptor (EGFR), cell division control protein 42 homolog (CDC42) were shown as the potential anticancer targets of monotropein against CRC. Molecular docking suggested that monotropein may interact with the 6 targets (Akt1, Akt2, CDK6, MMP9, EGFR, CDC42). Subsequently, cell activity of HCT116, HT29 and LoVo cell lines were significantly suppressed by monotropein (P<0.05). Furthermore, our research revealed that monotropein induced cell apoptosis by inhibiting Bcl-2 and increasing Bax, induced G1-S cycle arrest in colorectal cancer by decreasing the expressions of CyclinD1, CDK4 and CDK6, inhibited cell migration by suppressing the expressions of CDC42 and MMP9 (P<0.05), and might play an anticancer role through Akt signaling pathway. CONCLUSION: Monotropein exerts its antitumor effects primarily by arresting the cell cycle, causing cell apoptosis, and inhibiting cell migration. This indicates a high potential for developing novel medication for treating CRC.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proliferação de Células , Metaloproteinase 9 da Matriz , Simulação de Acoplamento Molecular , Ciclo Celular , Receptores ErbB , Apoptose , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Linhagem Celular Tumoral
6.
Phys Chem Chem Phys ; 26(3): 2066-2072, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38126725

RESUMO

The kagome lattice is one of the most intriguing topics to study. It has a frustrated flat band touching a set of Dirac bands and can possess various promising properties, such as ferromagnetism, superconductivity, and a non-trivial topology. Covalent organic frameworks (COFs) are a rare type of inorganic material, however, they can provide a platform for generating certain required lattices. Based on first-principles density functional theory calculations, we show that a newly synthesized two-dimensional COF named COF-SH has novel enantiomorphic kagome bands, which include two sets of flat bands touching the Dirac bands around the Fermi level. The Bloch wave of the flat-valence band at the K-point shows the kagome nature of the phase interference. Under charge doping, the COF-SH exhibits a ferromagnetic ground state. Moreover, when COF-SH is doped with iodine atoms, a sizable gap in the system is opened between the flat bands and the Dirac bands due to the spin-orbit coupling (SOC) effect. Meanwhile, the spin degeneracy is lifted since the organic layer loses electrons due to the oxidizing property of iodine. In addition, our tight-binding analysis with the SOC effect shows that the flat valence band separates from the Dirac bands and holds a nonzero Chern number. Consequently, this I-doped COF can give rise to a quantum anomalous Hall effect.

7.
Sci Rep ; 13(1): 20353, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990106

RESUMO

Fusarium head blight (FHB) is a critical fungal disease causes serious grain yield losses and mycotoxin contaminations. Currently, utilization of chemical fungicides is the main control method which has led to serious resistance. Development of novel synergist is an important strategy to reduce the usage of chemical fungicides and postpone the development of resistance, while natural components are interesting resources. In this study, the synergistic effect of Taxodium 'zhongshansha' essential oil (TZEO) was determined and the best synergistic ratio (SR) of 3.96 in laboratory which was observed when the weight ratio of TZEO and prothioconazole was 1 : 1 with the corresponding EC50 (half maximal effective concentration) value of Fusarium graminearum was 0.280 mg L-1. Subsequently, an increase of 6.31% on the control effect to FHB index in field test was observed when compared to the treatment with prothioconazole alone, though there was no significant difference between these treatments. Furthermore, we established an effective method to detect the mycotoxin contaminations in wheat grain with the limits of quantifications (LOQs) value of 5 µg kg-1 (DON, ZEN, 3-DON, and 15-DON) and 1 µg kg-1 (OTA) and the contents were less to the maximum residue limit (MRL) values. It was also shown that the application of 20% TZEO EW led to a 20% reduction in the use of prothioconazole, which was calculated based on the control effect values of 86.41% and 90.20% between the treatments of 30% prothioconazole OD (225 g a.i ha-1, recommend dosage) and 30% prothioconazole OD (180 g a.i ha-1) + 20% TZEO EW (225 mL ha-1), significantly. The initial residue of prothioconazole and prothioconazole-desthio was increased in the treatment with TZEO, which may play an important role in the synergistic effect on FHB. Moreover, none of the treatments posed a prothioconazole residue risk in the wheat grain and the environment. In addition, the essential oil has no any negative influence on wheat growth, which was revealed by a study of the chlorophyll content. These results provide an important botanical synergist for use with prothioconazole to control Fusarium head blight, and in-depth study to the synergistic mechanism of this oil is necessary in our future research.


Assuntos
Fungicidas Industriais , Fusarium , Micotoxinas , Óleos Voláteis , Fungicidas Industriais/farmacologia , Triticum , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Micotoxinas/farmacologia , Grão Comestível , Óleos Voláteis/farmacologia
8.
Ecotoxicol Environ Saf ; 267: 115591, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37890252

RESUMO

Honeybee is an essential pollinator to crops, evaluation to the risk assessment of honeybee larvae exposure to pesticides residue in the bee bread and honey is an important strategy to protect the bee colony due to the mixture of these two matrices is main food for 3-day-old honeybee larvae. In this study, a continuous survey to the residue of five pyrethroid insecticides in bee bread and honey between 2018 and 2020 from 17 major cultivation provinces which can be determined as Northeast, Northwest, Eastern, Central, Southwest, and Southern of China, there was at least one type II pyrethroid insecticide was detected in 54.7 % of the bee bread samples and 43.4 % of the honey. Then, we assayed the acute toxicity of type II pyrethroid insecticides based on the detection results, the LD50 value was 0.2201 µg/larva (beta-cyhalothrin), 0.4507 µg/larva (bifenthrin), 2.0840 µg/larva (fenvalerate), 0.0530 µg/larva (deltamethrin), and 0.1640 µg/larva (beta-cypermethrin), respectively. Finally, the hazard quotient was calculated as larval oral ranged from 0.046 × 10-3 to 2.128 × 10-3. Together, these empirical findings provide further insight into the accurate contamination of honey bee colonies caused by chemical pesticides, which can be used as a valuable guidance for the beekeeping industry and pesticide regulation.


Assuntos
Mel , Inseticidas , Praguicidas , Própole , Piretrinas , Abelhas , Animais , Larva , Inseticidas/toxicidade , Medição de Risco , Piretrinas/toxicidade
9.
Pestic Biochem Physiol ; 194: 105523, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532335

RESUMO

Diamondback moth (Plutella xylostella), a worldwide migratory pest that is developing strong resistance to various chemical insecticides. It has been determined that four natural pyrazines isolated from Allium tuberosum showed significant repellent activity to P. xylostella, but the molecular target still unknown. In the present study, a novel synthetic route for 2,3-dimethyl-6-(1-hydroxy)-pyrazine which has the most significant repellent activity with a purity of 90.60% was established. Simultaneously, the bioassay result declared that the repellent grade was IV at a dosage of 0.01 mg which was the same as to the published data. Transcriptomics analysis detected 1643 upregulated and 3837 downregulated genes in P. xylostella antennae following this pyrazine exposure. Then, 2142 differentially expressed genes were annotated using Gene Ontology and 2757 genes were annotated by Kyoto Encyclopedia of Genes and Genomes. Moreover, this procedure identified 84 odour perception-related genes, 58 odorant receptor (OR) genes including 57 conventional ORs and the odorant receptor co-receptor (Orco, atypical odorant receptor) gene, and 26 odorant-binding protein (OBP) genes. Based on quantitative real time PCR (RT-qPCR) and differential expression results, 9 OR genes including the Orco were cloned and characterised. In summary, this study provides important basis for the utilization of pyrazines as the main active ingredients or lead compounds to developing new botanical pesticides, which will reduce application of chemical pesticides and postpone the development of resistance.


Assuntos
Inseticidas , Mariposas , Receptores Odorantes , Animais , Receptores Odorantes/genética , Mariposas/genética , Inseticidas/farmacologia , Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase em Tempo Real , Resistência a Inseticidas/genética , Larva
10.
Biomater Sci ; 11(18): 6149-6159, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37548310

RESUMO

Controlled drug release of nanoparticles was achieved by irreversibly disrupting polymer micelles through high-intensity focused ultrasound (HIFU) induction. An ultrasound-responsive block copolymer was synthesized, comprising an end-functional Eosin Y fluorophore, 2-tetrahydropyranyl acrylate (THPA), and acrylate mannose (MAN). The block copolymer was then self-assembled to produce micelles. The chemotherapy drug dasatinib (DAS) and the sonodynamic therapy agent methylene blue (MB) were encapsulated by the self-assembly of the block copolymer. This targeted nanoparticle enables sonodynamic therapy through high-intensity focused ultrasound while triggering nanoparticle disassembly for controlled drug release. The ultrasound-mediated, non-invasive strategy provides external spatiotemporal control for targeted tumour treatment.


Assuntos
Micelas , Neoplasias , Humanos , Sistemas de Liberação de Medicamentos , Polímeros , Ultrassonografia , Liberação Controlada de Fármacos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
11.
Environ Sci Pollut Res Int ; 30(40): 93044-93053, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37498429

RESUMO

Previous studies to the exposure effects of acetamiprid on honeybees were based on the analysis of bee pollen and honey sacs from field trials or of beebread and honey in the hive, which overestimate or underestimate the risk of exposure to pesticide residues. It was believed that the processing factor (PF) is an important variable to determine the final pesticide residue during royal jelly formation and the actual risk to honeybee larva. Hence, a QuEChERS method to determine acetamiprid contents in honeybee samples was established in this study. Then, the PFs for acetamiprid in beebread fermentation, honey brewing, and royal jelly formation were determined to be 0.85, 0.76, and 0.16, respectively. The PF for royal jelly formation was 0.04 when acetamiprid was detected in beebread alone, and it was 0.12 when acetamiprid was only detected in honey. Finally, the predicted exposure concentration of acetamiprid in royal jelly was calculated to be 2.05 µg/kg using the PF without significant difference with the 90th percentile value (3.64 µg/kg) in the actual sample. However, the value was 16.62 µg/kg without considering the PF. This study establishes a methodology for the correct evaluation of the risk to bee larva of acetamiprid residues in bee pollen and honey sac contents and the residual levels in royal jelly.


Assuntos
Mel , Resíduos de Praguicidas , Própole , Abelhas , Animais , Larva , Mel/análise , Ácidos Graxos/análise , Resíduos de Praguicidas/análise , Digestão
12.
Animals (Basel) ; 13(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37106855

RESUMO

Wildlife residing in cities has made encounters between humans and wild animals a common phenomenon. The perspective of the conflict-laden animal-human relationship has been over-emphasized by traditional media, which neglects the peaceful and harmonious daily encounters between residents and urban wildlife. This paper addresses the lacuna in extant literature by examining the virtual encounters between urban residents and wildlife on TikTok by sharing the living habits of Falco tinnunculus. Participatory observation, semi-structured interviews, and text analysis were adopted to explore the knowledge production process of urban wildlife as well as the emotional response of audiences. We found that displaying urban wildlife in short videos is a dynamic process involving the mutual participation of wildlife and humans. Meanwhile, audiences' anthropocentric gaze of wildlife via TikTok attends to their desires for intimacy with nature and demonstrates the unequal and unbalanced power between wild animals and humans. These findings suggest that more efforts should be made to guide the public to pay attention to native urban wildlife species and to reflect upon the ethics and rationality of such unequal power relations between wild animals and humans.

13.
J Agric Food Chem ; 71(17): 6594-6602, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37075317

RESUMO

This study investigated the effects of light source, pH value, and NO3- concentration on the photodegradation of prothioconazole in aqueous solution. The half-life (t1/2) of prothioconazole was 173.29, 21.66, and 11.18 min under xenon, ultraviolet, and high-pressure mercury lamps, respectively. At pH values of 4.0, 7.0, and 9.0 under a xenon lamp light source, the t1/2 values were 693.15, 231.05, and 99.02 min, respectively. Inorganic substance NO3- clearly promoted the photodegradation of prothioconazole, with t1/2 values of 115.53, 77.02, and 69.32 min at NO3- concentrations of 1.0, 2.0, and 5.0 mg L-1, respectively. The photodegradation products were identified as C14H15Cl2N3O, C14H16ClN3OS, C14H15Cl2N3O2S, and C14H13Cl2N3 based on calculations and the Waters compound library. Furthermore, density functional theory (DFT) calculations showed that the C-S, C-Cl, C-N, and C-O bonds of prothioconazole were the reaction sites with high absolute charge values and greater bond lengths. Finally, the photodegradation pathway of prothioconazole was concluded, and the variation in energy of the photodegradation process was attributed to the decrease in activation energy caused by light excitation. This work provides new insight into the structural modification and photochemical stability improvement of prothioconazole, which plays an important role in decreasing safety risk during application that will reduce the exposure risk in field environment.


Assuntos
Poluentes Químicos da Água , Água , Fotólise , Água/química , Triazóis , Poluentes Químicos da Água/química , Xenônio , Cinética
14.
Molecules ; 28(6)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36985732

RESUMO

As an edible and medicinal fungus, Dictyophora indusiata is well-known for its morphological elegance, distinctive taste, high nutritional value, and therapeutic properties. In this study, eighteen compounds (1-18) were isolated and identified from the ethanolic extract of D. indusiata; four (1-4) were previously undescribed. Their molecular structures and absolute configurations were determined via a comprehensive analysis of spectroscopic data (1D/2D NMR, HRESIMS, ECD, and XRD). Seven isolated compounds were examined for their anti-inflammatory activities using an in vitro model of lipopolysaccharide (LPS)-simulated BV-2 microglial cells. Compound 3 displayed the strongest inhibitory effect on tumor necrosis factor-α (TNF-α) expression, with an IC50 value of 11.9 µM. Compound 16 exhibited the highest inhibitory activity on interleukin-6 (IL-6) production, with an IC50 value of 13.53 µM. Compound 17 showed the most potent anti-inflammatory capacity by inhibiting the LPS-induced generation of nitric oxide (NO) (IC50: 10.86 µM) and interleukin-1ß (IL-1ß) (IC50: 23.9 µM) and by significantly suppressing induced nitric oxide synthase (iNOS) and phosphorylated nuclear factor-kappa B inhibitor-α (p-IκB-α) expression at concentrations of 5 µM and 20 µM, respectively (p < 0.01). The modes of interactions between the isolated compounds and the target inflammation-related proteins were investigated in a preliminary molecular docking study. These results provided insight into the chemodiversity and potential anti-inflammatory activities of metabolites with small molecular weights in the mushroom D. indusiata.


Assuntos
Agaricales , Agaricales/metabolismo , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Simulação de Acoplamento Molecular , Anti-Inflamatórios/química , Óxido Nítrico/metabolismo
15.
Heliyon ; 9(2): e11880, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36852077

RESUMO

Background: There are many pharmaceutical interventions available to prevent osteoporotic vertebral fractures in postmenopausal women, but the efficacy and safety of these drugs are unknown. This study aimed to investigate the efficacy and safety of drugs in the prevention of osteoporotic vertebral fractures. Methods: PubMed, Embase, and the Cochrane Library were comprehensively searched for randomized controlled trials (RCTs) published up to February 15, 2020, including postmenopausal women with osteoporosis. Network meta-analysis was conducted based on the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The relative risk (RR) and 95% confidence interval (CI) were used to report the results. This study was registered with PROSPERO, number CRD42020201167. Main Outcomes were incidences of new vertebral fracture and serious adverse events. Results: Fifty-five RCTs (n = 104 580) evaluating vertebral fractures of sixteen kinds of pharmacologic therapies were included in the network meta-analysis. Abaloparatide (RR, 0.21; [95% CI, 0.09 to 0.51]), alendronate (RR, 0.55; [95% CI, 0.38 to 0.81]), calcitonin (RR, 0.44; [95% CI, 0.25 to 0.78]), denosumab (RR, 0.33; [95% CI, 0.14 to 0.61]), parathyroid hormone (PTH) (RR, 0.32; [95% CI, 0.10 to 0.97]), risedronate (RR, 0.65; [95% CI, 0.42 to 1.00]), romosozumab (RR, 0.31; [95% CI, 0.16 to 0.61]), strontium ranelate (RR, 0.62; [95% CI, 0.42 to 0.93]), teriparatide (RR, 0.27; [95% CI, 0.17 to 0.43]), and zoledronate (RR, 0.41; [95% CI, 0.93]) were associated with lower vertebral fracture risk compared to placebo. PTH was associated with more adverse event rates. For any two drug treatments, the RR of serious adverse events was not statistically significant. Hormone replacement therapy (HRT) and calcitonin may be slower to work because they have only been shown to reduce the risk of vertebral fractures in long-term (>18 months) follow-up. Conclusions: A variety of drugs are safe and effective in preventing osteoporotic vertebral fractures. HRT and calcitonin only reduced the risk of vertebral fractures during a follow-up of 21-72 months.

16.
J Asian Nat Prod Res ; 25(6): 564-570, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35929891

RESUMO

Two new sesquiterpenoids, named 9,10-dihydroxy-albaflavenone (1) and 5-hydroxy-albaflavenone (2) were isolated from Dictyophora indusiata. Their structures and absolute configurations were determined by NMR, ECD and HRESIMS. Compounds 1 and 2 showed anti-inflammatory activity by inhibiting TNF-α and NO secretion to varying degrees.


Assuntos
Basidiomycota , Sesquiterpenos , Basidiomycota/química , Sesquiterpenos/farmacologia , Fator de Necrose Tumoral alfa
17.
Front Plant Sci ; 14: 1280671, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38264019

RESUMO

Deep learning models have been widely applied in the field of crop disease recognition. There are various types of crops and diseases, each potentially possessing distinct and effective features. This brings a great challenge to the generalization performance of recognition models and makes it very difficult to build a unified model capable of achieving optimal recognition performance on all kinds of crops and diseases. In order to solve this problem, we have proposed a novel ensemble learning method for crop leaf disease recognition (named ELCDR). Unlike the traditional voting strategy of ensemble learning, ELCDR assigns different weights to the models based on their feature extraction performance during ensemble learning. In ELCDR, the models' feature extraction performance is measured by the distribution of the feature vectors of the training set. If a model could distinguish more feature differences between different categories, then it receives a higher weight during ensemble learning. We conducted experiments on the disease images of four kinds of crops. The experimental results show that in comparison to the optimal single model recognition method, ELCDR improves by as much as 1.5 (apple), 0.88 (corn), 2.25 (grape), and 1.5 (rice) percentage points in accuracy. Compared with the voting strategy of ensemble learning, ELCDR improves by as much as 1.75 (apple), 1.25 (corn), 0.75 (grape), and 7 (rice) percentage points in accuracy in each case. Additionally, ELCDR also has improvements on precision, recall, and F1 measure metrics. These experiments provide evidence of the effectiveness of ELCDR in the realm of crop leaf disease recognition.

18.
Phys Chem Chem Phys ; 24(48): 29882-29890, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36468446

RESUMO

Janus MoSSe with mirror asymmetry has recently emerged as a new two-dimensional (2D) material with a sizeable out-of-plane dipole moment. Here, based on first-principles calculations, we theoretically investigate the electronic properties of two patterns of 2D MoSSe/MoS2 van der Waals heterostructures (vdWHs). The electronic properties of MoSSe can be tuned by the intrinsic out-of-plane dipole field. When the Se side of the Janus layer faces the MoS2 layer, the dipole field points from the MoSSe layer towards the MoS2 layer, and the vdWH possesses a type-I band alignment which is desirable for light emission applications. With a reversal of the Janus layer, the intrinsic field inverts accordingly, and the band alignment becomes a typical type-II band alignment, which benefits carrier separation. Moreover, it possesses superior optical absorption (∼105 cm-1), and the calculated photocurrent density under visible-light radiation is up to 0.9 mA cm-2 in the MoSSe/MoS2 vdWH. Meanwhile, an external electric field and vertical strain can remarkably modulate the band alignment to switch it between type-I and type-II. Thus, MoSSe/MoS2 vdWHs have promising applications in next-generation photovoltaic devices.

19.
Am J Cancer Res ; 12(11): 5255-5270, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504888

RESUMO

Heterogeneity is a fundamental feature of human tumors and plays a major role in drug resistance and disease progression. In the present study, we selected single-cell-derived cell lines (SCDCLs) derived from Lewis lung carcinoma (LLC1) cells to investigate tumorigenesis and heterogeneity. SCDCLs were generated using limiting dilution. Five SCDCLs were subcutaneously injected into wild-type C57BL/6N mice; however, they displayed significant differences in tumor growth. Subclone SCC1 grew the fastest in vivo, whereas it grew slower in vitro. The growth pattern of SCC2 was the opposite to that of SCC1. Genetic differences in these two subclones showed marked differences in cell adhesion and proliferation. Pathway enrichment results indicate that signal transduction and immune system responses were the most significantly altered functional categories in SCC2 cells compared to those in SCC1 cells in vitro. The number and activation of CD3+ and CD8+ T cells and NK cells in the tumor tissue of tumor-bearing mice inoculated with SCC2 were significantly higher, whereas those of myeloid cells were significantly lower, than those in the SCC1 and LLC1 groups. Our results suggest that the in vivo growth of two subclones derived from LLC1 was determined by the tumor microenvironment rather than their intrinsic proliferative cell characteristics.

20.
Nat Commun ; 13(1): 7065, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36400776

RESUMO

Ugi reactions and related variations are proven to be atom and step-economic strategies for construction of highly valuable peptide-like skeletons and nitrogenous heterocycles. The development of structurally diverse range of novel catalytic systems and the discovery of new approaches to accommodate a broader scope of terminating reagents for asymmetric Ugi four-component reaction is still in high demand. Here, we report a strategy that enables enantioselective Ugi four-component and Ugi-azide reactions employing anionic stereogenic-at-cobalt(III) complexes as catalysts. The key nitrilium intermediates, generated through the nucleophilic addition of isocyanides to the chiral ion-pair which consists of stereogenic-at-cobalt(III) complexes counteranion and a protonated iminium, are trapped by either carboxylic acids or in situ-generated hydrazoic acid, delivering α-acylamino amides and α-aminotetrazoles in good to excellent enantioselectivities (up to 99:1 e.r.).


Assuntos
Azidas , Cobalto , Estereoisomerismo , Catálise , Cianetos
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