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1.
Huan Jing Ke Xue ; 45(9): 5117-5126, 2024 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-39323130

RESUMO

The cause of ozone pollution is a complex scientific problem. Studying the spatiotemporal variation characteristics of O3 at different time scales and analyzing the key influencing factors of O3 concentration is of great significance for the precise formulation of urban air pollution control measures and the improvement of urban air quality. Based on the analysis of the spatiotemporal variation characteristics of O3 concentration in Chuzhou City, we studied the 12 ozone-influencing factors of meteorology and pollutants at multiple time scales using Spearman correlation analysis and a random forest model. The results showed that: ① The O3 pollution level of Chuzhou City showed an aggravating trend, and the O3 concentration distribution showed a spatial pattern of "high in the southeast and low in the northwest." ② From February to May, SO2 concentration had a strong impact on the increase in O3 concentration. From June to September, PM2.5 and PM10 were significantly positively correlated with ozone and had a greater impact. ③ Relative humidity, temperature, and wind speed had a significant impact on O3, whereas barometric pressure and hourly rainfall had a weak impact. ④ The O3 pollution mechanism in Chuzhou City changed from "pollutant-controlled" to "meteorology-controlled." ⑤ Among meteorological and pollutant factors, the three influencing factors that had the greatest influence on O3 concentration were temperature, wind speed, and relative humidity, with PM10 concentration, PM2.5 concentration, and SO2 concentration also contributing. All of the above six influencing factors had a significant nonlinear relationship with the O3 concentration.

2.
Phys Rev E ; 110(2-1): 024211, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39294992

RESUMO

To show the impact of environmental noise on imitation dynamics, the stochastic stability and stochastic evolutionary stability of a discrete-time imitation dynamics with random payoffs are studied in this paper. Based on the stochastic local stability of fixation states and constant interior equilibria in a two-phenotype model, we extend the concept of stochastic evolutionary stability to the stochastic imitation dynamics, which is defined as a strategy such that, if all the members of the population adopt it, then the probability for any mutant strategy to invade the population successfully under the influence of natural selection is arbitrarily low. Our main results show clearly that the stochastic evolutionary stability of the system depends only on the properties of the mean matrix of the random payoff matrix and is independent of the randomness of the random payoff matrix. Moreover, as two examples, we show also that under the framework of stochastic imitation dynamics, the noise intensity affects the evolution of cooperative behavior in a stochastic prisoner's dilemma game and the system's nonlinear dynamic behavior.


Assuntos
Evolução Biológica , Processos Estocásticos , Meio Ambiente , Teoria dos Jogos
3.
Int J Biol Macromol ; 279(Pt 1): 134952, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39197630

RESUMO

The purified neutral polysaccharide fraction, namely SBP-1, was isolated and characterized from Schisandra chinensis (Turcz.) Baill crude polysaccharides, which have anti-Parkinson's disease activity were investigated in vivo and in vitro. Experiments have shown that the main chain of SBP-1 was Glcp-(1→, →4)-Glcp-(1→ and →4,6)-Glcp-(1→. We also revealed the effect of SBP-1 on the PD mice model and the potential underlying molecular mechanism. The results showed that SBP-1 administration improved behavioral deficits, increased tyrosine hydroxylase-positive cells, attenuated loss of dopaminergic neurons in MPTP-exposed mice, and reduced cell death induced by MPP+. The MCL-1 was identified as the target of SBP-1 by the combination of docking-SPR-ITC, WB, and IF experiments. Subsequently, the study showed that SBP-1 could target MCL-1 to enhance autophagy with a change in the apoptotic response, which was further demonstrated by a change in LC3/P62, PI3K/AKT/mTOR, and possesses a change in the expression of BCL2/BAX/Caspase3. These results demonstrate that SBP-1 may protect neurons against MPP+ or MPTP-induced damage in vitro and in vivo through enhancing autophagy. In summary, these findings indicate that SBP-1 and S. chinensis show potential as effective candidates for further investigation in the prevention and treatment of PD or associated illnesses, specifically through autophagy apoptotic-based mechanisms.

4.
Nat Prod Res ; : 1-11, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39015011

RESUMO

Three new compounds 1-glyceryl 9(ß), 10(α), 11(ß)-trihydroxy-12(Z)-octadecenoate, 2'S-20-O-p-hydroxyphenylpropionyloxy-20-hyd-roxyarachidic acid glycerol ester (2), 3-O-α-l-arabinopyranosyl-(1→6)-ß-d-glucopyranoside of ethyl (3S)-hydroxybutanoate (3), as well as a new natural product (4) were isolated from the fruits of Solanum virginianum L. The structures of 26 compounds were determined by comprehensive spectroscopic analyses, NMR calculation, chemical methods, and comparisons of spectroscopic data. Compounds 2 and 16 exhibited good anti-inflammatory activity in the LPS-induced RAW 264.7 inflammatory model with IC50 values of 16.75 ± 1.54 and 22.43 ± 2.01 µM, respectively.

5.
Nat Commun ; 15(1): 5849, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38992001

RESUMO

The effective isolation of rare target cells, such as circulating tumor cells, from whole blood is still challenging due to the lack of a capturing surface with strong target-binding affinity and non-target-cell resistance. Here we present a solution leveraging the flexibility of bacterial virus (phage) nanofibers with their sidewalls displaying target circulating tumor cell-specific aptamers and their ends tethered to magnetic beads. Such flexible phages, with low stiffness and Young's modulus, can twist and adapt to recognize the cell receptors, energetically enhancing target cell capturing and entropically discouraging non-target cells (white blood cells) adsorption. The magnetic beads with flexible phages can isolate and count target cells with significant increase in cell affinity and reduction in non-target cell absorption compared to magnetic beads having rigid phages. This differentiates breast cancer patients and healthy donors, with impressive area under the curve (0.991) at the optimal detection threshold (>4 target cells mL-1). Immunostaining of captured circulating tumor cells precisely determines breast cancer subtypes with a diagnostic accuracy of 91.07%. Our study reveals the power of viral mechanical attributes in designing surfaces with superior target binding and non-target anti-fouling.


Assuntos
Neoplasias da Mama , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Neoplasias da Mama/virologia , Feminino , Aptâmeros de Nucleotídeos/metabolismo , Nanofibras/química , Linhagem Celular Tumoral , Bacteriófagos/genética
6.
Z Naturforsch C J Biosci ; 79(9-10): 285-290, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-38780504

RESUMO

Nine compounds were isolated and identified from ethanolic extracts of Saposhnikovia divaricata, including one new alkaloid (1), one new pentacyclic triterpenoid (9), and seven known alkaloids (2-8). Structural elucidation of compounds 1 and 9 was established by 1D and 2D NMR spectra referring to the literature, together with high-resolution mass spectrometric analysis. All compounds were evaluated for antiproliferative activity against two cancer cell lines (LN229, A549) in vitro. Compounds (1-9) showed no significant antiproliferative activity.


Assuntos
Alcaloides , Proliferação de Células , Extratos Vegetais , Humanos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Alcaloides/química , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Apiaceae/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Células A549
7.
Biosensors (Basel) ; 14(5)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38785706

RESUMO

The development of gel electrophoresis-based biodetection assays for point-of-care analysis are highly demanding. In this work, we proposed a ratiometric gel electrophoresis-based biosensing platform by employing catalytic hairpin assembly (CHA) process functions as both the signal output and the signal amplification module. Two types of nucleic acids, DNA and miRNA, are chosen for demonstration. The proposed strategy indeed provides a new paradigm for the design of a portable detection platform and may hold great potential for sensitive diagnoses.


Assuntos
Técnicas Biossensoriais , DNA , MicroRNAs , MicroRNAs/análise , Catálise , Eletroforese , Ácidos Nucleicos/análise
8.
Nat Prod Res ; : 1-10, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563116

RESUMO

Phytochemical investigation of the roots of Saposhnikovia divaricata (Turcz.) Schischk resulted in the isolation of twelve coumarin derivatives including one new 3,4-dihydroisocoumarin (1) and eleven known 3,4-unsubstituted coumarins (2-12). Structural elucidation of compounds 1-12 was established by 1D and 2D NMR spectra referring to the literature, together with high-resolution mass spectrometric analysis. LPS-induced RAW264.7 inflammatory cell model was used to determine the potential antiinflammation activity of all the isolated compounds in vitro. The results showed that compound 3 significantly inhibited the production of lipopolysaccharide (LPS)-induced NO in macrophages (IC50 = 4.54 ± 1.71 µM), more active than the positive control (L-NMMA).

9.
Fitoterapia ; 175: 105883, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38458497

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease in the world. As one of the major degradation pathways, autophagy plays a pivotal role in maintaining the effective turnover of proteins and damaged organelles in cells. Lewy bodies composed of α-synuclein (α-syn) abnormally aggregated in the substantia nigra are important pathological features of PD, and autophagy dysfunction is considered to be an important factor leading to abnormal aggregation of α-syn. Phenylpropionamides (PHS) in the seed of Cannabis sativa L. have a protective effect on neuroinflammation and antioxidant activity. However, the therapeutic role of PHS in PD is unclear. In this study, the seeds of Cannabis sativa L. were extracted under reflux with 60% EtOH-H2O, and the 60% EtOH-H2O elution fraction was identified as PHS with the UPLC-QTOF-MS. The 1-methyl-4-phenyl-1,2,3,6-tetrahydro-pyridine (MPTP)-induced PD model in C57BL/6 J mice was used for behavioral and pharmacodynamic experiments. Behavioral symptoms were improved, Nissl-stained and TH-positive neurons in the substantia nigra were significantly increased in PHS-treated MPTP-induced PD model mice. Compared with the model group, PHS treatment reduced the expression level of α-syn, and the expression of TH increased significantly by western blotting, compared with the model group, the PHS group suppressed Caspase 3 and Bax expression and promoted Bcl-2 expression and levels of p62 decreased significantly, the ratio of LC3-II/I and p-mTOR/mTOR in the PHS group had a downward trend, suggesting that the therapeutic effect of PHS on MPTP-induced PD model mice may be triggered by the regulation of autophagy.


Assuntos
Autofagia , Cannabis , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores , Sementes , Animais , Autofagia/efeitos dos fármacos , Camundongos , Sementes/química , Cannabis/química , Masculino , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/isolamento & purificação , Doença de Parkinson/tratamento farmacológico , Substância Negra/efeitos dos fármacos , Modelos Animais de Doenças , Serina-Treonina Quinases TOR/metabolismo
10.
Fitoterapia ; 174: 105876, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38431027

RESUMO

Nine polyacetylenes, including five new compounds named sadivaethynes E-I (1-5), were isolated from the roots of Saposhnikovia divaricata. Structural elucidation of compounds 1-5 was established by extensive spectroscopic analysis, quantum chemical calculations and DP4+ probability analysis. Among them, the absolute configuration of compound 1-2, 4-5 was unambiguous determined by ECD. Also, all compounds were evaluated for cytotoxicity against two human cancer cell lines (A549, HEPG2) in vitro, compound 9 showed moderate inhibitory effect with an IC50 value of 11.66 µM against HEPG2.


Assuntos
Apiaceae , Poli-Inos , Humanos , Estrutura Molecular , Poli-Inos/farmacologia , Poli-Inos/análise , Poli-Inos/química , Raízes de Plantas/química , Extratos Vegetais/química , Apiaceae/química
11.
Front Plant Sci ; 15: 1333207, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38344186

RESUMO

With the rapid development of the livestock industry, finding new sources of feed has become a critical issue that needs to be addressed urgently. China is one of the top five sunflower producers in the world and generates a massive amount of sunflower stalks annually, yet this resource has not been effectively utilized. Therefore, in order to tap into the potential of sunflower stalks for animal feed, it is essential to explore and develop efficient methods for their utilization.In this study, various proportions of alfalfa and sunflower straw were co-ensiled with the following mixing ratios: 0:10, 2:8, 4:6, 5:5, 6:4, and 8:2, denoted as A0S10, A2S8, A4S6, A5S5, A6S4, and A8S2, respectively. The nutrient composition, fermentation quality, microbial quantity, microbial diversity, and broad-spectrum metabolomics on the 60th day were assessed. The results showed that the treatment groups with more sunflower straw added (A2S8, A4S6) could start fermentation earlier. On the first day of fermentation, Weissella spp.dominated overwhelmingly in these two groups. At the same time, in the early stage of fermentation, the pH in these two groups dropped rapidly, which could effectively reduce the loss of nutrients in the early stage of fermentation.In the later fermentation period, a declining trend in acetic acid levels was observed in A0S10, A2S8, and A4S6, while no butyric acid production was detected in A0S10 and A2S8 throughout the process. In A4S6, butyric acid production was observed only after 30 days of fermentation. From the perspective of metabolites, compared with sunflower ensiling alone, many bioactive substances such as flavonoids, alkaloids, and terpenes are upregulated in mixed ensiling.

12.
Fitoterapia ; 174: 105874, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417684

RESUMO

Five new sesquiterpenoids, dictamtrinorguaianols E and F (1-2), and dictameudesmnosides F, G, and H (3-5), along with seven known sesquiterpenoids (6-12) were isolated from Dictamnus dasycarpus Turcz. The structures of all new compounds were characterized by spectroscopic methods, including UV, IR, HR-ESI-MS, and 1D and 2D NMR. The In-vitro anti-proliferative activities of all the compounds against two human cancer cell lines (SW982 and A549) were evaluated by CCK-8 assay. Compounds 1 and 4 showed medium anti-proliferative activity against SW982 cells, with IC50 values of 3.49 ± 0.10 and 6.42 ± 1.23 µM, respectively. Additionally, compounds 2, 7, and 8 exhibited medium anti-proliferative activity against A549 cells, with IC50 values ranging from 0.80 ± 0.05 to 6.60 ± 0.46 µM.


Assuntos
Dictamnus , Sesquiterpenos , Humanos , Dictamnus/química , Estrutura Molecular , Linhagem Celular , Espectroscopia de Ressonância Magnética , Sesquiterpenos/farmacologia
13.
Nat Prod Res ; : 1-8, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38232058

RESUMO

Two new quinoline alkaloids (1-2) together with twenty-two known alkaloids (3-24) were isolated and identified from Dictamnus dasycarpus Turcz. Compounds 6-7, 9, 11, 15-16, 19 and 24 were isolated from D. dasycarpus for the first time. The structures of all compounds were characterised by spectroscopic methods (1D, 2D NMR and HRESIMS). The anti-proliferative activity was mediated by the arrest of three human cancer cell lines (SW982, HepG2 and A549) of all the compounds that were evaluated by CCK-8 assay.

14.
Phytochemistry ; 218: 113941, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38049078

RESUMO

Thirteen previously undescribed steroidal saponins, named parisverticilloside A-M (1-13) and twenty known steroidal saponins (14-33) were isolated from ethanol extract of the roots of Paris verticillata. Their structures were identified by a series of spectroscopic methods, including 1D and 2D NMR, HR-ESI-MS, optical rotatory dispersion and chemical processes. The anti-proliferative activities of all compounds against LN229, HepG2, MDA-MB-231 and 4T1 cell lines were evaluated using the CCK8 assay with cisplatin or capecitabine as the positive control. The anti-inflammatory activities of all compounds were measured by inhibition of LPS-induced NO release from BV2 cell lines, with dexamethasone as the positive control.


Assuntos
Liliaceae , Saponinas , Raízes de Plantas/química , Linhagem Celular , Saponinas/farmacologia , Saponinas/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Estrutura Molecular
15.
Chem Biodivers ; 21(2): e202301655, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38084071

RESUMO

Six novel withanolides, along with nine known related compounds were isolated from the leaves of Datura stramonium L. The structures and absolute configurations of the new withanolides were elucidated by employing various spectral techniques and comparing them with those previously reported in the literature. In addition, four withanlides demonstrated interesting cytotoxic activity on LN229 cells with IC50 <20 µM.


Assuntos
Antineoplásicos , Datura stramonium , Vitanolídeos , Vitanolídeos/farmacologia , Vitanolídeos/química , Estrutura Molecular , Folhas de Planta/química
16.
Huan Jing Ke Xue ; 44(8): 4666-4678, 2023 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-37694659

RESUMO

Exploring the spatial and temporal pattern evolution of habitat quality and carbon storage has a positive feedback effect on establishing an ecological security barrier and optimizing the spatial pattern of national land in the WeiBei Arid Plateau Region of Shaanxi. This study took the Weibei Plateau Region as a case study, simulated the spatial pattern of land use for different development scenarios of 2035 based on the PLUS model, and used the InVEST model to analyze the characteristics of habitat quality and carbon storage distribution in the study area from 1980 to 2020 and under multi-scenarios in the future. The results showed that:①the area of the low-grade habitat quality area in the study area expanded by 462.55 km2, and the carbon stock decreased by 7.85×106 t over the past 40 years, both of which showed an overall decreasing trend yearly. ②During the study period, the degraded habitat quality areas were concentrated in the northeastern part of the study area within Yan'an City, and the upgraded areas were distributed in strips near water sources or at higher elevations. The high carbon stock areas were concentrated in the complex terrain and sparsely populated areas in the study area, and the decreasing carbon stocked areas were scattered throughout the study area in a dotted pattern without obvious aggregation. ③In 2035, carbon stock decreased to different degrees in all states except for the natural development scenario. In the economic priority development scenario, the habitat quality low grade area covered 20787.41 km2, which was the simulated scenario of the fastest growth rate of low-grade area and the largest reduction of high-grade area compared with the early stage of the simulation. The results of this study can provide decision references and data support for low carbon green development and ecological restoration in the study area.

17.
Z Naturforsch C J Biosci ; 78(11-12): 415-420, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-37748096

RESUMO

Eleven compounds were isolated and identified from ethanolic extracts of Solanum virginianum fruits, including two new compounds (1-2) and nine known compounds (3-11). Their structures were determined to be melongenaterpene C15-O-ß-D-glucopyranoside (1), (9Z)-3,7,11,15-tetramethyl -hexadeca-1,6,10-triene-3,5,14,15-tetraol-5-O-ß-D-glucopyranoside (2), actini-dioionoside A (3), byzantionoside B (4), citroside A (5), 7Z-roseoside (6), matenoside A (7), megastigmane (8), dihydrophaseic acid 3'-O-ß-D-glucopyranoside (9), taraxerol (10), and huzhangoside C (11). In this paper, NMR spectroscopy was used to study the structures of the compounds, comparing their data with those in the literature. In addition, the potential anti-inflammatory activity of the compounds was also evaluated using the RAW264.7 cell inflammation model induced by lipopolysaccharide (LPS). The terpenoids showed no significant anti-inflammatory activity.


Assuntos
Frutas , Solanum , Frutas/química , Terpenos/farmacologia , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia
18.
Heliyon ; 9(6): e16729, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37346327

RESUMO

Super-rational aspiration induced strategy updating with exit rights has been considered in some previous studies, in which the players adjust strategies in line with their payoffs and aspirations, and they have access to exit the game. However, exit payoffs for exiting players are automatically allocated, which is clearly contrary to reality. In this study, evolutionary cooperation dynamics with super-rational aspiration and asymmetry in the Prisoner's Dilemma game is investigated, where exit payoffs are implemented by local peers. The results show that for different population structures, the asymmetry of the system is always contributive to the participation of the players. Furthermore, we show that under different exit payoffs, super-rationality and asymmetry are conductive to the evolution of cooperation.

19.
Foods ; 12(7)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37048359

RESUMO

Apiculture has been greatly developed in recent years in China. Beekeeping cooperatives and honey manufacturing enterprises have increased rapidly. As a result, a variety of honey products have entered the market, adding vitality to the food economy; however, the adulteration of honey products is on the rise in China. Previous attempts to control the adulteration of honey products mostly relied on technical, product-specific measures, and there was a lack of modeling research to guide the supervision of the honey product industry. In order to help local governments to better control the adulteration of honey products from a management perspective, this paper establishes an evolutionary game model composed of beekeeping cooperatives, honey product enterprises, and local governments. Through stability analysis and model simulation, we found that local government subsidies to cooperatives have little impact on the game system. Local government penalties to cooperatives and price adjustments of unadulterated raw honey by cooperatives are effective management tools to reduce the adulteration behavior of cooperatives. Local government penalties for enterprises are an effective management tool to reduce the adulteration behavior of enterprises. This research provides useful information for government agencies to design appropriate policies/business modes so as to promote sustainability and the healthy development of the honey product industry in China.

20.
Nat Prod Res ; 37(4): 551-559, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35574640

RESUMO

Three new compounds, 4,5,6,7-tetramethoxy-3-benzoylbenzofuran (1), 4-hydroxy-3,5,6-trimethoxydihydrochalcone-2-O-ß-D-glucopyranoside (2) and 2-hydroxy-3,4,5,6-tetramethoxyphenylethyl benzoate (3) along with five known flavonoids were isolated from the dichloromethane fraction of the stems of Fissistigma acuminatissimum Merr.'s ethanol extracts. The compounds were obtained by chromatographic methods and the structure elucidation was completed primarily on the basis of spectroscopic analyses, all of these compounds were isolated from F. acuminatissimum for the first time. All the fractions and compounds were evaluated for their anti-inflammatory activity against lipopolysaccharide (LPS)-stimulated tumor necrosis factor α (TNF-α) production in RAW264.7 cells in vitro. The dichloromethane fraction showed the most potent inhibition(38.2%) at 60 µg/mL, compound 1 (70.2%) and 3 (65.2%) showed significant inhibition at 10 µM.


Assuntos
Annonaceae , Annonaceae/química , Cloreto de Metileno , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Flavonoides/farmacologia , Flavonoides/química
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