Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 57
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Radiol Med ; 129(2): 252-267, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38015363

RESUMO

OBJECTIVE: To develop and validate an iodine maps-based radiomics nomogram for preoperatively predicting cervical lymph node metastasis (LNM) in head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: A total of 278 patients who pathologically confirmed as HNSCC were retrospectively recruited from two medical centers between June 2012 and July 2022. The training set (n = 152) and internal set (n = 67) were randomly selected from medical center A, and the patients from medical center B were enrolled as the external set (n = 69). The minority group in the training set was balanced by the adaptive synthetic sampling (ADASYN) approach. Radiomics features were extracted from dual-energy CT-derived iodine maps at arterial phase (AP) and venous phase (VP), respectively. Three radiomics signatures were constructed to predict the LNM by using a random forest algorithm. The independent clinical predictors for LNM were identified by multivariate analysis and combined with radiomics signatures to establish a radiomic-clinical nomogram. The performance of radiomic-clinical nomogram was evaluated with respect to its discrimination and clinical usefulness. RESULTS: The AP-VP-incorporated radiomics model exhibited a great predictive performance for LNM prediction with an area under curve (AUC) of 0.885 (95% CI, 0.836-0.933) in ADASYN-training set and confirmed in all validation sets. The nomogram that incorporated AP-VP radiomics signatures, CT-reported LN status, and histological grades yielded AUCs of 0.920 (95% CI, 0.881-0.959) in ADASYN-training set, 0.858 (95% CI, 0.771-0.944) in internal validation, and 0.849 (95% CI, 0.752-0.946) in external validation, with good calibration in all cohorts (p > 0.05). Decision curve analyses indicated the nomogram was clinically useful. In addition, the predictive performance of clinical-radiomics nomogram was also validation in combing cohorts. Stratified analysis confirmed the stability of nomogram, particularly in group negative for CT-reported LNM. CONCLUSION: Clinical-radiomics nomogram based on iodine maps exhibited promising performance in predicting LNM and providing valuable information for making individualized therapy decisions.


Assuntos
Neoplasias de Cabeça e Pescoço , Tomografia Computadorizada por Raios X , Humanos , Metástase Linfática/diagnóstico por imagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Radiômica , Linfonodos/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem
2.
Prep Biochem Biotechnol ; 53(3): 308-316, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35670651

RESUMO

Purification of total flavonoids from Ginkgo biloba flowers (GBF) extracts were studied using six resins. Adsorption-desorption experiments indicated that polyamide resin is the most suitable resin. The optimal purification process of total flavonoids of GBF was as follows: a loading concentration of 5.85 mg/mL, a loading volume of 1 bed volume (BV), a loading flow rate of 2 BV/h, a water volume of 2.67 BV, and a desorption solution of 40% ethanol. Under these conditions, the maximum purity of total flavonoids was 37.1 ± 1.1%. The antioxidant activity of purified flavonoids was further evaluated in vitro. It showed that the 40% ethanol purified fraction (Fr. B) group had the strongest antioxidant activity of the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity concentration for 50% of maximal effect (EC50, 145.4 ± 13.8 µg/mL) and ferric reducing ability (2.5 ± 0.2 mM FeSO4 equivalent mg-1 Fr. B). In addition, at the concentration of 160 µg/mL, the Fr. B strikingly increased the viability rate of hydrogen peroxide stimulated PC-12 cells to normal levels (***p < 0.001). This method provides a basis for the application and development of GBF resources. It indicated that the purified GBF flavonoids can be used as a source of potential antioxidant.


Assuntos
Flavonoides , Ginkgo biloba , Flavonoides/farmacologia , Flavonoides/química , Ginkgo biloba/química , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Cromatografia , Flores
3.
Molecules ; 28(9)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37175238

RESUMO

Alkaloids are a material treasure bestowed on humans by nature owing to their numerous biological activities. Orychophragine D, an alkaloid isolated from the seeds of Orychophragmus violaceus was identified as bearing a novel skeleton and proved to have an excellent radioprotective effect. Different from the common alkaloid structure, the main block of orychophragine D is constructed of an oxotriazine and an oxopiperazine, which are connected in parallel by a C-N bond. In this paper, a preparation method for the novel heterocycle skeleton of orychophragine D is proposed for the first time. N-Boc-L-serine was utilized as the original material to complete the preparation with 11 steps in a 13% overall yield. A hydroxyl group was established on the side chain of the skeleton as the reaction site for researchers to conduct further structural modification or derivatization.


Assuntos
Alcaloides , Antineoplásicos , Humanos , Alcaloides/farmacologia , Alcaloides/química , Sítios de Ligação , Esqueleto , Estrutura Molecular
4.
Entropy (Basel) ; 24(10)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37420480

RESUMO

The finite-time synchronization (FNTS) problem for a class of delayed fractional-order fully complex-valued dynamic networks (FFCDNs) with internal delay and non-delayed and delayed couplings is studied by directly constructing Lyapunov functions instead of decomposing the original complex-valued networks into two real-valued networks. Firstly, a mixed delay fractional-order mathematical model is established for the first time as fully complex-valued, where the outer coupling matrices of the model are not restricted to be identical, symmetric, or irreducible. Secondly, to overcome the limitation of the use range of a single controller, two delay-dependent controllers are designed based on the complex-valued quadratic norm and the norm composed of its real and imaginary parts' absolute values, respectively, to improve the synchronization control efficiency. Besides, the relationships between the fractional order of the system, the fractional-order power law, and the settling time (ST) are analyzed. Finally, the feasibility and effectiveness of the control method designed in this paper are verified by numerical simulation.

5.
Soft Matter ; 17(47): 10730-10735, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34787153

RESUMO

A programming methodology, which can be applied to soft-magnetic-material-based magneto-active elastomers (MAEs), to catch the predefined specific objective curves is proposed in this study. The objective curves have been equally separated into a couple of segments, which will be filled by the designed MAE elements. Furthermore, the designed MAE segments with different chain angles, in which the deformation orientation of each element under applied homogeneous magnetic fields has been investigated based on the designed experimental setup, are arrayed based on the proposed programming methodology to constitute the MAE composite to catch the orientation of the objective curve. The experimental results show that based on the proposed programming methodology, the MAE composites can describe different curves, which include harmonic, tangential and arc tangential functions under applied homogeneous magnetic fields with good agreement. Furthermore, on the basis of the proposed programming methodology, the MAE composites are utilized to mimic the typical biomimetic behavior (the peeking-up behavior of snakes and the flapping behavior of birds) with smooth curvature properties, in which the dynamic procedures present continuous curves.


Assuntos
Biomimética , Elastômeros , Comportamento Imitativo , Campos Magnéticos
6.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209219

RESUMO

Ginkgo biloba L. has always been a popular area of research due to its various active ingredients and pharmacological effects. Ginkgo biloba is rich in ginkgo flavonoids, ginkgolides, and ginkgolic acid, with anti-inflammation, antioxidation, neuroprotection, anti-platelet agglutination, hypolipidemic effect, anti-cancer, and anti-radiation properties. There are many methods to extract and separate the active components of ginkgo. Among them, supercritical carbon dioxide fluid extraction (SFE-CO2) is known for its green, clean, and environment-friendly properties. In this paper, the pharmacological activities, the active components, and structures of different parts of ginkgo, the extraction methods of its effective ingredients, and the application of the SFE-CO2 method for the extraction and separation of active ingredients in Ginkgo biloba from leaves, seeds, pollen, and roots were reviewed, in order to make best use of ginkgo resources, and provide support and references for the development of SFE-CO2 of active components from Ginkgo biloba.


Assuntos
Dióxido de Carbono/química , Ginkgo biloba/química , Ginkgolídeos , Extratos Vegetais/química , Folhas de Planta/química , Ginkgolídeos/química , Ginkgolídeos/isolamento & purificação
7.
Proc Natl Acad Sci U S A ; 114(19): 5047-5052, 2017 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-28439024

RESUMO

Members of the aquaporin (AQP) family have been suggested to transport aluminum (Al) in plants; however, the Al form transported by AQPs and the roles of AQPs in Al tolerance remain elusive. Here we report that NIP1;2, a plasma membrane-localized member of the Arabidopsis nodulin 26-like intrinsic protein (NIP) subfamily of the AQP family, facilitates Al-malate transport from the root cell wall into the root symplasm, with subsequent Al xylem loading and root-to-shoot translocation, which are critical steps in an internal Al tolerance mechanism in Arabidopsis We found that NIP1;2 transcripts are expressed mainly in the root tips, and that this expression is enhanced by Al but not by other metal stresses. Mutations in NIP1;2 lead to hyperaccumulation of toxic Al3+ in the root cell wall, inhibition of root-to-shoot Al translocation, and a significant reduction in Al tolerance. NIP1;2 facilitates the transport of Al-malate, but not Al3+ ions, in both yeast and Arabidopsis We demonstrate that the formation of the Al-malate complex in the root tip apoplast is a prerequisite for NIP1;2-mediated Al removal from the root cell wall, and that this requires a functional root malate exudation system mediated by the Al-activated malate transporter, ALMT1. Taken together, these findings reveal a critical linkage between the previously identified Al exclusion mechanism based on root malate release and an internal Al tolerance mechanism identified here through the coordinated function of NIP1;2 and ALMT1, which is required for Al removal from the root cell wall, root-to-shoot Al translocation, and overall Al tolerance in Arabidopsis.


Assuntos
Alumínio/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Raízes de Plantas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico Ativo/fisiologia , Transportadores de Ânions Orgânicos/genética , Raízes de Plantas/genética
8.
J Environ Sci (China) ; 95: 58-64, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32653193

RESUMO

Hydroxyl free radicals (OH radicals) play the main role in atmospheric chemistry and their involving reactions are the dominant rate determining step in the formation of secondary fine particulate matter and in the removal of air pollutants from the atmosphere. In this paper, we studied the seasonal variation characteristics of OH radicals during the daytime in Lanzhou and explored the potential formation mechanism of high concentration OH radicals. We found that the OH radicals in four seasons was 2.7 × 106, 2.6 × 106, 3.1 × 106, and 2.2 × 106 cm-3, respectively. Since the rainfall was concentrated in summer, the wet deposition had a significant effect on removing OH radicals. Among the four pollutants (including ozone (O3), volatile organic compounds (VOCs), nitrogen dioxide (NO2) and fine particulate matter (PM2.5)), the variation of OH radicals were closely related to ozone concentration especially in spring and summer. In autumn, the correlation between PM2.5 and OH radicals were the closest among the observing pollutants and its formation mechanism was different conventional regeneration pathway. In Event 1, high concentration of ozone was the main source of OH radicals; under the high humidity condition, except for ozone, the multiple factors including VOCs, NO2 and PM2.5 interplayed and leaded to the Event 2.


Assuntos
Poluentes Atmosféricos/análise , Ozônio/análise , Atmosfera , Monitoramento Ambiental , Radical Hidroxila/análise , Material Particulado/análise , Estações do Ano
9.
BMC Microbiol ; 19(1): 36, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30744555

RESUMO

BACKGROUND: A major facilitator superfamily transporter Dehp2 was recently shown to be playing an important role in transport and biodegradation of haloacids in Paraburkholderia caribensis MBA4, and Dehp2 is phylogenetically conserved in Burkholderia sensu lato. RESULTS: We designed both Burkholderia sensu stricto-specific and Paraburkholderia-specific qPCR assays based on dehp2 and 16S rRNA, and validated the qPCR assays in 12 bacterial strains. The qPCR assays could detect single species of Burkholderia sensu stricto or Paraburkholderia with high sensitivity and discriminate them in mixtures with high specificity over a wide dynamic range of relative concentrations. At relatively lower cost compared with sequencing-based approach, the qPCR assays will facilitate discrimination of Burkholderia sensu stricto and Paraburkholderia in a large number of samples. CONCLUSIONS: For the first time, we report the utilization of a haloacids transporter gene for discriminative purpose in Burkholderia sensu lato. This enables not only quick decision on proper handling of putative pathogenic samples in Burkholderia sensu stricto group but also future exploitation of relevant species in Paraburkholderia group for haloacids biodegradation purposes.


Assuntos
Burkholderia/genética , Burkholderiaceae/genética , Proteínas de Transporte/genética , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Filogenia , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
10.
Chem Res Toxicol ; 32(6): 1281-1288, 2019 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-31046239

RESUMO

Aloe-emodin (AE) is a major anthraquinone ingredient of numerous traditional Chinese medicines with a variety of beneficial biological activities in vitro. Previous studies suggested that AE possessed cytotoxicity and genotoxicity. Nevertheless, the mechanisms of the toxic action of AE have not yet been fully clarified. The present study aimed at characterization of metabolic pathways of AE to better understand the mechanisms of AE-induced cytotoxicity. An AE-derived glutathione conjugate (AE-GSH) was observed in rat liver cytosol incubations containing AE and GSH, along with 3'-phosphoadenosine-5'-phosphosulfate (PAPS). Similar incubation fortified with N-acetylcysteine (NAC) in place of GSH offered an AE-NAC conjugate corresponding to the GSH conjugate. The formation of the two conjugates was found to require PAPS. The two conjugates were respectively detected in bile and urine of rats given AE. Sulfotransferase (SULT) inhibitor pentachlorophenol (PCP) suppressed the production of the observed AE-GSH/NAC conjugates in vivo, which suggested that SULTs participated in the process of the metabolic activation of AE. The presence of PCP attenuated cell susceptibility to AE-induced cytotoxicity. The present study illustrated potential association of sulfation-mediated bioactivation of AE with its cytotoxicity.


Assuntos
Antraquinonas/farmacologia , Sulfotransferases/metabolismo , Ativação Metabólica/efeitos dos fármacos , Animais , Antraquinonas/química , Antraquinonas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Citosol/química , Citosol/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Células Hep G2 , Humanos , Fígado/química , Fígado/metabolismo , Masculino , Estrutura Molecular , Pentaclorofenol/farmacologia , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Sulfotransferases/antagonistas & inibidores
11.
Chem Res Toxicol ; 32(2): 234-244, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30672276

RESUMO

Aloe-emodin (AE), an anthraquinone derivative, is a bioactive ingredient isolated from rhubarb which is used to treat inflammatory illnesses in China and many other countries in Asia. AE has shown a wide range of pharmacological effects. Recent studies showed that exposure to AE could cause DNA damage and cytotoxicity. The goals of the present study are aimed at (1) exploration of oxidative metabolism pathways of AE, (2) identification of P450 enzymes which respond the hydroxylation of AE, and (3) determination of electrophilicity of AE and its oxidative metabolites. Two hydroxylation metabolites (M1 and M2) and four GSH conjugates (M3-M6) were found in incubations consisting of AE, rat or human liver microsomes, and NADPH supplemented with GSH. Conjugates M3 and M4 came from AE itself, and M5 and M6 originated from M1 and M2 individually. M1 and M2 (5-hydroxy aloe-emodin) and M3-M6 were also detected in rat primary hepatocytes after exposure to AE. Additionally, biliary M3, M4, and M6 were detected in rats given AE. Urinary M1, M2, and M7 (a NAC conjugate) were observed in animals administered AE. Recombinant P450 enzyme incubations illustrated that hydroxylation of AE was primarily catalyzed by P450 1A2, 3A4, and 3A5. The metabolism investigation will help us to better understand the biochemical mechanisms of cytotoxicity induced by AE.


Assuntos
Aloe/química , Emodina/metabolismo , Compostos de Sulfidrila/química , Aloe/metabolismo , Animais , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Emodina/química , Emodina/toxicidade , Glutationa/química , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Hidroxilação , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Espectrometria de Massas em Tandem
12.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438617

RESUMO

We load the natural active molecules onto the spin film in an array using electrospinning techniques. The electrospun active molecular membranes we obtain in optimal parameters exhibit excellent capacity for scavenging radical. The reaction capacity of three different membranes for free radicals are shown as follow, glycyrrhizin acid membrane > quercetin membrane > α-mangostin membrane. The prepared active molecular electrospun membranes with a large specific surface area and high porosity could increase the interaction area between active molecules and free radicals. Additionally, it also has improved anti-airflow impact strength, anti-contaminant air molecular interference ability, and the ability to capture free radicals.


Assuntos
Eletroquímica/métodos , Radicais Livres/química , Ácido Glicirrízico/química , Membranas Artificiais , Xantonas/química
13.
Biochim Biophys Acta ; 1858(12): 3061-3070, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27668346

RESUMO

Haloacids are considered to be environmental pollutants, but some of them have also been tested in clinical research. The way that haloacids are transported across biological membranes is important for both biodegradation and drug delivery purposes. In this review, we will first summarize putative haloacids transporters and the information about haloacids transport when studying carboxylates transporters. We will then introduce MCT1 and SLC5A8, which are respective transporter for antitumor agent 3-bromopyruvic acid and dichloroacetic acid, and monochloroacetic acid transporters Deh4p and Dehp2 from a haloacids-degrading bacterium. Phylogenetic analysis of these haloacids transporters and other monocarboxylate transporters reveals their evolutionary relationships. Haloacids transporters are not studied to the extent that they deserve compared with their great application potentials, thus future inter-discipline research are desired to better characterize their transport mechanisms for potential applications in both environmental and clinical fields.


Assuntos
Ácido Dicloroacético/farmacocinética , Piruvatos/farmacocinética , Animais , Transporte Biológico , Membrana Celular/metabolismo , Humanos , Transportadores de Ácidos Monocarboxílicos/fisiologia , Filogenia , Simportadores/fisiologia
14.
Int J Mol Sci ; 15(9): 16302-19, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25226538

RESUMO

This study describes the extraction, preliminary characterization and evaluation of the in vitro antitumor and antioxidant activities of polysaccharides extracted from Mentha piperita (MPP). The optimal parameters for the extraction of MPP were obtained by Box-Behnken experimental design and response surface methodology (RSM) at the ratio of water to raw material of 20, extraction time of 1.5 h and extraction temperature at 80 °C. Chemical composition analysis showed that MPP was mainly composed of glucuronic acid, galacturonic acid, glucose, galactose and arabinose, and the molecular weight of its two major fractions were estimated to be about 2.843 and 1.139 kDa, respectively. In vitro bioactivity experiments showed that MPP not only inhibited the growth of A549 cells but possessed potent inhibitory action against DNA topoisomerase I (topo I), and an appreciative antioxidant action as well. These results indicate that MPP may be useful for developing safe natural health products.


Assuntos
Antioxidantes/química , Mentha piperita/metabolismo , Polissacarídeos/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antioxidantes/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA Topoisomerases Tipo I/química , DNA Topoisomerases Tipo I/metabolismo , Humanos , Radical Hidroxila/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxidos/química , Temperatura
15.
Neural Netw ; 172: 106118, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38232421

RESUMO

This article focuses on the tradeoff analysis between time and energy costs for fixed-time synchronization (FXTS) of discontinuous neural networks (DNNs) with time-varying delays and mismatched parameters. First, a more comprehensive lemma is systematically established to study fixed-time stability, which is less conservative than those in most current results. Besides, theoretical proof has proven that the upper bounds of the settling time (ST) in this article are more accurate compared to existing results. Second, on the grounds of the new fixed-time stability lemma, fixed-time synchronization problem for discontinuous neural networks with time-varying delays and mismatched parameters is explored, and sufficient conditions for fixed-time synchronization are obtained. Further, the upper bounds of energy cost during the synchronization process are estimated. Third, in order to achieve a balance between time cost and energy cost, the genetic algorithm is utilized to find the satisfactory control parameter. Finally, a numerical example is provided to verify the theoretical analysis's correctness and the control mechanism's feasibility.


Assuntos
Algoritmos , Redes Neurais de Computação , Fatores de Tempo , Fenômenos Físicos
16.
Drug Test Anal ; 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38403949

RESUMO

Recent progress in gene editing has enabled development of gene therapies for many genetic diseases, but also made gene doping an emerging risk in sports and competitions. By delivery of exogenous transgenes into human body, gene doping not only challenges competition fairness but also places health risk on athletes. World Anti-Doping Agency (WADA) has clearly inhibited the use of gene and cell doping in sports, and many techniques have been developed for gene doping detection. In this review, we will summarize the main tools for gene doping detection at present, highlight the main challenges for current tools, and elaborate future utilizations of high-throughput sequencing for unbiased, sensitive, economic and large-scale gene doping detections. Quantitative real-time PCR assays are the widely used detection methods at present, which are useful for detection of known targets but are vulnerable to codon optimization at exon-exon junction sites of the transgenes. High-throughput sequencing has become a powerful tool for various applications in life and health research, and the era of genomics has made it possible for sensitive and large-scale gene doping detections. Non-biased genomic profiling could efficiently detect new doping targets, and low-input genomics amplification and long-read third-generation sequencing also have application potentials for more efficient and straightforward gene doping detection. By closely monitoring scientific advancements in gene editing and sport genetics, high-throughput sequencing could play a more and more important role in gene detection and hopefully contribute to doping-free sports in the future.

17.
Carbohydr Res ; 539: 109120, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669825

RESUMO

Xanthoceras sorbifolium Bunge, also known as Tu-Mu-Gua and Wen-Dan-Ge-Zi, has several applications. Clinical data and experimental studies have shown anti-tumor, anti-inflammatory, anti-bacterial, and anti-oxidant properties of Xanthoceras sorbifolium Bunge that inhibits prostate hyperplasia, lowers blood pressure and lipid level, and treats enuresis and urinary incontinence. It also has neuroprotective effects and can treat Alzheimer's disease and Parkinson's syndrome. The research on the chemical composition and pharmacological effects of Xanthoceras sorbifolium Bunge has been increasing. Triterpenoid and triterpenoid saponins are the main constituents in Xanthoceras sorbifolium Bunge and exhibit biological activities. In this review, we summarized the research progress on triterpenoids and their glycosides in Xanthoceras sorbifolia, including the chemical constituents, pharmacological activities, and biogenic pathways of triterpenoid mother nucleus. The results would provide a reference for further research and development of triterpenoids and their glycosides in Xanthoceras sorbifolia.


Assuntos
Saponinas , Triterpenos , Saponinas/química , Saponinas/farmacologia , Saponinas/isolamento & purificação , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/isolamento & purificação , Humanos , Sapindaceae/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação
18.
Nat Commun ; 14(1): 163, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36631471

RESUMO

Functional soft materials, exhibiting multiple types of deformation, have shown their potential/abilities to achieve complicated biomimetic behaviors (soft robots). Inspired by the locomotion of earthworm, which is conducted through the contraction and stretching between body segments, this study proposes a type of one-piece-mold folded diaphragm, consisting of the structure of body segments with radial magnetization property, to achieve large 3D and bi-directional deformation with inside-volume change capability subjected to the low homogeneous magnetically driving field (40 mT). Moreover, the appearance based on the proposed magnetic-driven folded diaphragm is able to be easily customized to desired ones and then implanted into different untethered soft robotic systems as soft drivers. To verify the above points, we design the diaphragm pump providing unique properties of lightweight, powerful output and rapid response, and the soft robot including the bio-earthworm crawling robot and swimming robot inspired by squid to exhibit the flexible and rapid locomotion excited by single homogeneous magnetic fields.


Assuntos
Diafragma , Oligoquetos , Animais , Biomimética , Locomoção/fisiologia , Natação , Oligoquetos/fisiologia , Fenômenos Magnéticos
19.
Artigo em Inglês | MEDLINE | ID: mdl-37632623

RESUMO

Achieving carbon neutrality has become a global common goal. For China, to reach peak carbon emissions and long-term carbon neutrality, the transformation and development of resource-based cities are essential. This study uses data from 114 prefecture-level resource-based cities from 2008 to 2019 as a sample and empirically tests the impact of industrial land mismatch on carbon emissions using the fixed effects model. In addition, we analyze the heterogeneous influence of environmental regulation as a moderating effect on resource-based cities at different development stages. The study reveals that (1) there is a significant positive correlation between the imbalance in industrial land supply in resource-based cities and carbon emissions. The more severe the imbalance, the higher the carbon emissions. The improper supply mode of industrial land is also positively correlated with carbon emissions, although the impact is not significant. (2) Environmental regulation can significantly curb the carbon emission issues caused by the mismatch and imbalance in the scale of industrial land supply and the improper supply mode of industrial land. (3) Compared to strong resource-based cities, weak resource-security cities have a smaller impact on carbon emissions due to an imbalance in the supply of industrial land. This is mainly because resources in weak resource-security cities are becoming exhausted, making "ecology first, green and low carbon" the main tune for economic and social development. Both types of cities show a positive correlation between the improper supply of industrial land and carbon emissions, although neither is significant. (4) The intensity of the regulatory effect of environmental regulations on resource-based cities is influenced by resource abundance. The suppression of carbon emissions by environmental regulations is more apparent in strong resource-security cities than in weak resource-security cities.

20.
Heliyon ; 9(12): e22824, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125553

RESUMO

As heavy metals in soil could enrich in biomass and pose health risk to human, it is vital to monitor their contaminations to ensure qualified agricultural production. In this study, we collected >4000 soil samples from agricultural fields in Shanghai during 2010∼2020, and unveiled heavy metal contamination status in this metropolitan. We found that although Shanghai has a long industrialization history, the heavy metal levels in agricultural soil are within safe ranges according to national standard. Specifically, the median levels of Cd, Hg, As, Pb, Cr and Cu are 0.11, 0.13, 7.47, 23.80, 41.00 and 28.30 mg/kg, respectively, which are as good as, or even better than national averages. However, there are spatial and temporal heterogeneities for heavy metal contaminations in Shanghai. For example, the levels of Cd, Hg and Cr are relatively higher in some districts with high industry density, which should be further monitored in the future. Moreover, while the levels for Cd, Cr and Pb have decreased, the level for Hg has mildly increased during this period which needs counteractive measures. Correlation analysis of heavy metal levels and soil fertility parameters suggested overuse of fertilizers may be related to heavy metal contamination in some regions. In summary, our study present by far the largest and most comprehensive landscape of heavy metal contamination in Shanghai agricultural soil, which will be useful for future policy-design and land use planning to ensure safe agricultural production.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA