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1.
Curr Atheroscler Rep ; 26(8): 435-449, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38814418

RESUMEN

PURPOSE OF REVIEW: Vascular dementia (VaD) is the second most prevalent type of dementia after Alzheimer's disease.Hypercholesterolemia may increase the risk of dementia, but the association between cholesterol and cognitive function is very complex. From the perspective of peripheral and brain cholesterol, we review the relationship between hypercholesterolemia and increased risk of VaD and how the use of lipid-lowering therapies affects cognition. RECENT FINDINGS: Epidemiologic studies show since 1980, non-HDL-C levels of individuals has increased rapidly in Asian countries.The study has suggested that vascular risk factors increase the risk of VaD, such as disordered lipid metabolism. Dyslipidemia has been found to interact with chronic cerebral hypoperfusion to promote inflammation resulting in cognitive dysfunction in the brain.Hypercholesterolemia may be a risk factor for VaD. Inflammation could potentially serve as a link between hypercholesterolemia and VaD. Additionally, the potential impact of lipid-lowering therapy on cognitive function is also worth considering. Finding strategies to prevent and treat VaD is critical given the aging of the population to lessen the load on society. Currently, controlling underlying vascular risk factors is considered one of the most effective methods of preventing VaD. Understanding the relationship between abnormal cholesterol levels and VaD, as well as discovering potential serum biomarkers, is important for the early prevention and treatment of VaD.


Asunto(s)
Colesterol , Demencia Vascular , Hipercolesterolemia , Humanos , Demencia Vascular/etiología , Demencia Vascular/epidemiología , Demencia Vascular/metabolismo , Hipercolesterolemia/complicaciones , Hipercolesterolemia/epidemiología , Factores de Riesgo , Colesterol/metabolismo , Colesterol/sangre
2.
J Colloid Interface Sci ; 670: 28-40, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38754329

RESUMEN

Inversion symmetry broken 3R phase transition metal dichalcogenides (TMDs) show fascinating prospects in spintronics, valleytronics, and nonlinear optics. However, the controlled synthesis of 3R phase TMDs is still a great challenge. In this work, two-dimensional 3R-NbSe2 single crystals up to 0.2 mm were synthesized for the first time through chemical vapor deposition method by designing a space-confined system. The crystal size and morphology can be controlled by the location of the stacked substrates and the amount of the Nb2O5 precursor. Scanning transmission electron microscopy and Raman measurements reveal the NbSe2 exhibits a pure 3R stacking mode with relatively weak interlayer van der Waals interactions. Importantly, 3R-NbSe2 shows obvious second harmonic generation signal which intensity intensified as thickness increases. Density functional theory calculations and optical absorption demonstrate the coexistence of metallic and semiconducting optical properties of 3R-NbSe2. We designed a NbSe2/WS2/NbSe2 photodetector utilizing the metallicity of 3R-NbSe2, which shows good performance especially an ultrafast response (6-7 µs, 0.5 ms - 7.9 s for Au electrodes in literature). The proposed strategy and findings are of great significance for the growth of many other 3R-TMDs and applications of nonlinear optical and ultrafast devices.

3.
Int J Nanomedicine ; 19: 3315-3332, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38617797

RESUMEN

Background: Acute myocardial infarction (AMI) is a common cardiovascular disease in clinic. Currently, there is no specific treatment for AMI. Carbon dots (CDs) have been reported to show excellent biological activities, which hold promise for the development of novel nanomedicines for the treatment of cardiovascular diseases. Methods: In this study, we firstly prepared CDs from the natural herb Curcumae Radix Carbonisata (CRC-CDs) by a green, simple calcination method. The aim of this study is to investigate the cardioprotective effect and mechanism of CRC-CDs on isoproterenol (ISO) -induced myocardial infarction (MI) in rats. Results: The results showed that pretreatment with CRC-CDs significantly reduced serum levels of cardiac enzymes (CK-MB, LDH, AST) and lipids (TC, TG, LDL) and reduced st-segment elevation and myocardial infarct size on the ECG in AMI rats. Importantly, cardiac ejection fraction (EF) and shortening fraction (FS) were markedly elevated, as was ATPase activity. In addition, CRC-CDs could significantly increase the levels of superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT), and reduce the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) in myocardial tissue, thereby exerting cardioprotective effect by enhancing the antioxidant capacity of myocardial tissue. Moreover, the TUNEL staining image showed that positive apoptotic cells were markedly declined after CRC-CDs treatment, which indicate that CRC-CDs could inhibit cardiomyocyte apoptosis. Importantly, The protective effect of CRC-CDs on H2O2 -pretreated H9c2 cells was also verified in vitro. Conclusion: Taken together, CRC-CDs has the potential for clinical application as an anti-myocardial ischemia drug candidate, which not only provides evidence for further broadening the biological application of cardiovascular diseases, but also offers potential hope for the application of nanomedicine to treat intractable diseases.


Asunto(s)
Infarto del Miocardio , Isquemia Miocárdica , Animales , Ratas , Peróxido de Hidrógeno , Infarto del Miocardio/tratamiento farmacológico , Miocardio , Carbono
4.
Dent Res Oral Health ; 7(1): 8-14, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38404561

RESUMEN

The recent rise of powerful large language model (LLM)-based AI tools, exemplified by ChatGPT and Bard, poses a great challenge to contemporary dental education. It simultaneously offers a unique resource that potentially complements today's teaching and learning, where existing widely available learning resources have often fallen short. Although the LLM tools will shape both the clinical and educational aspects of dentistry profoundly, the didactic curricula, which primarily rely on lecture-based courses where instructors impart knowledge through presentations and discussions, need to be upgraded urgently. In this paper, we used dental course materials, syllabi, and textbooks adopted currently in the School of Dentistry (SOD) at Meharry Medical College to assess the potential utility and effectiveness of ChatGPT in dental education. We collected the responses of the chatbot to questions as well as students' interactions with it for assessment. Our results showed that ChatGPT can assist in dental essay writing and generate relevant content for dental students, in addition to other benefits. The limitations of ChatGPT were also discussed in the paper.

5.
Plant Physiol Biochem ; 207: 108425, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38368728

RESUMEN

As climate change continues to negatively impact our farmlands, abiotic factors like salinity and drought stress increasingly threaten global food security. The development of elite germplasms with resistance to multiple abiotic stresses is essential for breeding climate-resilient wheat cultivars. In this study, we determined that the previously reported salt-tolerant st1 mutant, obtained via spaceflight mutagenesis, may also resist to drought stress at the seedling stage. Moreover, our field trial revealed that yield-related traits including plant height, 1000-grain weight, and spike number per plant were significantly increased in st1 compared to the wild type. An F2 population of 334 individuals derived from a cross between the wild type and st1 displayed a bimodal distribution indicating that st1 plant height is controlled by a single major gene. Our Bulked Segregant Analysis and exome capture sequencing indicate that this gene is located on chromosome 4D. Further genetic linkage and gene sequence analysis suggests that a reverse mutation of Rht2 is putatively responsible for plant height variation in st1. Our genotypic and phenotypic analysis of the F2 population and F3 lines indicate that this reverse mutation significantly increases plant height and thousand grain weight but slightly decreases spike number per plant. Together, these results supply helpful information for the utilization of Rht2 in wheat breeding and provide an important material for breeding environmentally resilient, high-yield wheat varieties.


Asunto(s)
Vuelo Espacial , Triticum , Humanos , Triticum/genética , Fitomejoramiento , Fenotipo , Mutación/genética , Grano Comestible
6.
ISA Trans ; 146: 308-318, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38199841

RESUMEN

This paper proposes an extended state observer (ESO) based data-driven set-point learning control (DDSPLC) scheme for a class of nonlinear batch processes with a priori P-type feedback control structure subject to nonrepetitive uncertainties, by only using the process input and output data available in practice. Firstly, the unknown process dynamics is equivalently transformed into an iterative dynamic linearization data model (IDLDM) with a residual term. A radial basis function neural network is adopted to estimate the pseudo partial derivative information related to IDLDM, and meanwhile, a data-driven iterative ESO is constructed to estimate the unknown residual term along the batch direction. Then, an adaptive set-point learning control law is designed to merely regulate the set-point command of the closed-loop control structure for realizing batch optimization. Robust convergence of the output tracking error along the batch direction is rigorously analyzed by using the contraction mapping approach and mathematical induction. Finally, two illustrative examples from the literature are used to validate the effectiveness and advantage of the proposed design.

7.
Microbiol Spectr ; 12(2): e0348223, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38230927

RESUMEN

Periodontitis has recently been defined as a dysbiotic disease caused by an imbalanced oral microbiota. The transition from commensal microbial communities to periodontitis-associated ones requires colonization by specific pathogens, including Porphyromonas gingivalis. We previously reported an antagonistic relationship between Streptococcus cristatus and P. gingivalis. To determine the role of S. cristatus in altering the interactions of P. gingivalis with other oral bacteria in a complex context, we collected dental plaque samples from patients with periodontitis and assigned them to two groups based on the ratios of S. cristatus and P. gingivalis. We then characterized the microbial profiles of the dental plaque samples using shotgun metagenomic sequencing and compared the oral microbial composition and functional capabilities of the group with high S. cristatus-P. gingivalis ratios with the low ratio group. Taxonomic annotation revealed significant differences in the microbial composition at both the genus and species levels between the low and high S. cristatus-P. gingivalis ratio groups. Notably, a higher microbial diversity was observed in the samples with low S. cristatus-P. gingivalis ratios. Furthermore, the antibiotic resistance gene profiles of the two groups were also distinct, with a significantly increased abundance of the genes in the dental plaque samples with low S. cristatus-P. gingivalis ratios. It, therefore, indicates that the S. cristatus-P. gingivalis ratios influenced the virulence potential of the oral microbiome. Our work shows that enhancing the S. cristatus-P. gingivalis ratio in oral microbial communities can be an attractive approach for revising the dysbiotic oral microbiome.IMPORTANCEPeriodontitis, one of the most common chronic diseases, is linked to several systemic diseases, such as cardiovascular disease and diabetes. Although Porphyromonas gingivalis is a keystone pathogen that causes periodontitis, its levels, interactions with accessory bacteria and pathobionts in the oral microbiome, and its association with the pathogenic potential of the microbial communities are still not well understood. In this study, we revealed the role of Streptococcus cristatus and the ratios of S. cristatus and P. gingivalis in modulating the oral microbiome to facilitate a deeper understanding of periodontitis and its progression. The study has important clinical implications as it laid a foundation for developing novel non-antibiotic therapies against P. gingivalis and improving the efficiency of periodontal treatments.


Asunto(s)
Placa Dental , Microbiota , Periodontitis , Streptococcus , Humanos , Porphyromonas gingivalis/genética
8.
J Colloid Interface Sci ; 657: 529-537, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38070338

RESUMEN

Two-dimensional (2D) transition metal dichalcogenides are highly suitable for constructing junction photodetectors because of their suspended bond-free surface and adjustable bandgap. Additional stable layers are often used to ensure the stability of photodetectors. Unfortunately, they often increase the complexity of preparation and cause performance degradation of devices. Considering the self-passivation behavior of TaSe2, we designed and fabricated a novel self-powered TaSe2/WS2/TaSe2 asymmetric heterojunction photodetector. The heterojunction photodetector shows excellent photoelectric performance and photovoltaic characteristics, achieving a high responsivity of 292 mA/W, an excellent specific detectivity of 2.43 × 1011 Jones, a considerable external quantum efficiency of 57 %, a large optical switching ratio of 2.6 × 105, a fast rise/decay time of 43/54 µs, a high open-circuit voltage of 0.23 V, and a short-circuit current of 2.28 nA under 633 nm laser irradiation at zero bias. Moreover, the device also shows a favorable optical response to 488 and 532 nm lasers. Notably, it exhibits excellent environmental long-term stability with the performance only decreasing âˆ¼ 5.6 % after exposed to air for 3 months. This study provides a strategy for the development of air-stable self-powered photodetectors based on 2D materials.

9.
J Ethnopharmacol ; 322: 117668, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38159829

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Mailuo shutong pill (MLST) has been widely used in clinical treatment of superficial thrombotic phlebitis (STP). Nevertheless, the major active components of MLST and the mechanism of synergistic action have not been reported. AIM OF THE STUDY: The present study aimed to evaluate the improving effects and the underlying mechanism of MLST on mannitol-induced STP in rabbits. MATERIAL AND METHODS: In this study, Ultrahigh-performance liquid chromatography electrospray ionization quadrupole-exactive orbitrap mass spectrometry (UHPLC-ESI-Q-Exactive-Orbitrap-MS) was used to analyze and identify the chemical composition of MLST and the prototype components absorbed into the blood. Then, according to the prototype components in serum, the targets and mechanisms of MLST were explored by applying network pharmacology. The rabbit model of STP was established by injecting 20% mannitol into bilateral auricular vein. The pathological changes of rabbit ear tissues, inflammatory factors, coagulation function and hemorheology were detected. In addition, molecular docking verified the interaction between the main active ingredient and the key target. Finally, the PI3K/AKT pathway and its regulated downstream pathways were verified by Western blot. RESULTS: A total of 96 MLST components and 53 prototypical components absorbed into the blood were successfully identified. Based on network pharmacology, PI3K/AKT pathway and 10 chemical components closely related to this pathway were obtained. Hematoxylin-eosin (HE) staining results indicated that MLST effectively improved of the pathological damage of ear tissues. MLST decreased levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 and C-reactive protein (CRP). The expression of platelets (PLT) and fibrinogen concentration (FIB) was decreased, while prothrombin time (PT) and activated partial thromboplastin time (APTT) were prolonged. In addition, the plasma viscosity and whole blood viscosity in the MLST groups were significantly decreased. The more important discovery was that the expressions of P-PI3K, VEGF, P-AKT, P-IκB-α, P-NF-κB, NLRP3, ASC, Cleaved IL-1ß and Cleaved Caspase-1 were effectively reversed after treatment with MLST. CONCLUSIONS: This study comprehensively analyzed and characterized the chemical composition of MLST and the prototypical components absorbed into the blood. This study strongly confirmed the pharmacodynamic effect of MLST on STP. More importantly, this pharmacodynamic effect was achieved through inhibition of the PI3K/AKT pathway and its regulated NF-κB and NLRP3 pathways.


Asunto(s)
Medicamentos Herbarios Chinos , Tromboflebitis , Animales , Conejos , Proteína con Dominio Pirina 3 de la Familia NLR , Simulación del Acoplamiento Molecular , Tipificación de Secuencias Multilocus , FN-kappa B , Farmacología en Red , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Manitol , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico
10.
Artículo en Inglés | MEDLINE | ID: mdl-38017658

RESUMEN

Two-dimensional (2D) self-driven photodetectors have a wide range of applications in wearable, imaging, and flexible electronics. However, the preparation of most self-powered photodetectors is still complex and time-consuming. Simultaneously, the constant work function of a metal, numerous defects, and a large Schottky barrier at the 2D/metal interface hinder the transmission and collection of optical carriers, which will suppress the optical responsivity of the device. This paper proposed a self-driven graphene/WSe2/graphene (Gr/WSe2/Gr) photodetector with asymmetric Schottky van der Waals (vdWs) contacts. The vdWs contacts are formed by transferring Gr as electrodes using the dry-transfer method, obviating the limitations of defects and Fermi-level pinning at the interface of electrodes made by conventional metal deposition methods to a great extent and resulting in superior dynamic response, which leads to a more efficient and faster collection of photogenerated carriers. This work also demonstrates that the significant surface potential difference of Gr electrodes is a crucial factor to ensure their superior performance. The self-driven Gr/WSe2/Gr photodetector exhibits an ultrahigh Ilight/Idark ratio of 106 with a responsivity value of 20.31 mA/W and an open-circuit voltage of 0.37 V at zero bias. The photodetector also has ultrafast response speeds of 42.9 and 56.0 µs. This paper provides a feasible way to develop self-driven optoelectronic devices with a simple structure and excellent performance.

11.
Res Sq ; 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-37986988

RESUMEN

The recent rise of powerful large language model (LLM)-based AI tools, exemplified by ChatGPT and Bard, poses a great challenge to contemporary dental education while simultaneously offering a unique resource and approach that potentially complements today's teaching and learning, where existing widely available learning resources have often fallen short. Although both the clinical and educational aspects of dentistry will be shaped profoundly by the LLM tools, the didactic curricula, which primarily rely on lecture-based courses where instructors impart knowledge through presentations and discussions, need to be upgraded urgently. In this paper, we used dental course materials, syllabi, and textbooks adopted currently in the School of Dentistry (SOD) at Meharry Medical College to assess the potential utility and effectiveness of ChatGPT in dental education. We collected the responses of the chatbot to questions as well as students' interactions with it for assessment. Our results showed that ChatGPT can assist in dental essay writing and generate relevant content for dental students, in addition to other benefits. The limitations of ChatGPT were also discussed in the paper.

12.
PeerJ ; 11: e16222, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38025678

RESUMEN

Introduction: Sepsis is a life-threatening disease that damages multiple organs and induced by the host's dysregulated response to infection with high morbidity and mortality. Heart remains one of the most vulnerable targets of sepsis-induced organ damage, and sepsis-induced cardiomyopathy (SIC) is an important factor that exacerbates the death of patients. However, the underlying genetic mechanism of SIC disease needs further research. Methods: The transcriptomic dataset, GSE171564, was downloaded from NCBI for further analysis. Gene expression matrices for the sample group were obtained by quartile standardization and log2 logarithm conversion prior to analysis. The time series, protein-protein interaction (PPI) network, and functional enrichment analysis via Gene Ontology and KEGG Pathway Databases were used to identify key gene clusters and their potential interactions. Predicted miRNA-mRNA relationships from multiple databases facilitated the construction of a TF-miRNA-mRNA regulatory network. In vivo experiments, along with qPCR and western blot assays, provided experimental validation. Results: The transcriptome data analysis between SIC and healthy samples revealed 221 down-regulated, and 342 up-regulated expressed genes across two distinct clusters. Among these, Tpt1, Mmp9 and Fth1 were of particular significance. Functional analysis revealed their role in several biological processes and pathways, subsequently, in vivo experiments confirmed their overexpression in SIC samples. Notably, we found TPT1 play a pivotal role in the progression of SIC, and silencing TPT1 showed a protective effect against LPS-induced SIC. Conclusion: In our study, we demonstrated that Tpt1, Mmp9 and Fth1 have great potential to be biomarker of SIC. These findings will facilitated to understand the occurrence and development mechanism of SIC.


Asunto(s)
Cardiomiopatías , MicroARNs , Sepsis , Humanos , Metaloproteinasa 9 de la Matriz/genética , Redes Reguladoras de Genes , MicroARNs/genética , Cardiomiopatías/etiología , Sepsis/complicaciones , ARN Mensajero/genética
13.
Int Immunopharmacol ; 125(Pt A): 111090, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37866312

RESUMEN

Rheumatoid arthritis (RA) is an inflammatory-mediated autoimmune disease characterized by persistent joint enlargement, synovial cartilage damage, and inflammatory infiltrates. Although the pathogenesis and treatment of RA are still currently insufficient, the importance of the intestine flora, metabolism and immunity for RA has been gradually recognized, and many intestine regulatory strategies have been used to treat RA. However, the relationship between RA and intestine flora, metabolism and immunity has not been fully expounded. In this study, Complete Freund's Adjuvant (CFA) was used to establish RA model, CyTOF technology was used to study the changes of intestinal immune cell types, 16S rRNA technology was used to analyze the differences of intestinal flora, and LC-MS technology was used to explain the effects of metabolites produced by the changed intestinal flora on RA. Moreover, we systematically explored how the imbalance of intestinal flora changed the intestinal immune status through its metabolites in RA mice. Our results showed that the intestinal flora of RA mice changed significantly, and the bacteria producing short-chain fatty acids (SCFAs), indole classes and secondary bile acids were significantly reduced. The abundance of SCFAs, indole classes and secondary bile acids in the intestine were significantly decreased. The balance of immune cells in the intestine of RA mice was significantly disrupted, with an overall decrease in immune cells. This work reveals the possible relationship between intestinal flora, metabolism and immunity and RA in mice, which will provide new therapeutic strategies for RA.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Microbioma Gastrointestinal , Ratones , Animales , Adyuvante de Freund , ARN Ribosómico 16S/genética , Ratones Endogámicos C57BL , Artritis Reumatoide/tratamiento farmacológico , Intestinos/patología , Indoles/uso terapéutico , Ácidos y Sales Biliares , Artritis Experimental/tratamiento farmacológico
14.
Res Sq ; 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37674718

RESUMEN

Background: Periodontitis has been recently defined as a dysbiotic disease resulting from imbalanced oral microbiota. The transition of microbial communities from commensal to periodontitis-associated ones likely requires colonization by specific pathogens, including Porphyromonas gingivalis. We previously reported an antagonistic relationship between Streptococcus cristatus and P. gingivalis and the role of S. cristatus in inhibition of the biofilm formation, invasion, and gingipain enzymatic activity of P. gingivalis. Given the importance of P. gingivalis as a keystone pathogen of polymicrobial communities, the determinants of P. gingivalis levels, its interaction with the core microbiota, and association with the pathogenic potential of the microbial communities need to be addressed. Results: This present study intends to determine the role of S. cristatus in altering interactions of P. gingivalis with other oral bacteria in a complex context. We collected dental plaque samples from periodontitis patients and assigned them into two groups based on their ratios of S. cristatus and P. gingivalis. We then characterized microbial profiles of the dental plaque samples using shotgun metagenomic sequencing and subsequently compared oral microbial composition and functional capabilities between groups with high or low S. cristatus-P. gingivalis ratios. Taxonomic annotation showed significant differences in microbial compositions at both genus and species levels between the two groups. Notably, a higher microbial composition diversity was observed in the samples with low S. cristatus-P. gingivalis ratios. The antibiotic resistance gene profiles of the two groups are also distinct, with significantly increased diversity and abundance of antibiotic resistance genes in the dental plaque samples with low S. cristatus-P. gingivalis ratios, which likely lead to elevated virulence potential. Conclusions: Overall, our work highlights the importance of S. cristatus-P. gingivalis ratios in influencing the virulence of the oral microbiome. Approaches to enhance S. cristatus-P. gingivalis ratios in oral microbial communities will be attractive for revising the dysbiotic oral microbiome.

15.
Plant J ; 116(6): 1652-1666, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37696505

RESUMEN

TEMPRANILLO1 (TEM1) is a transcription factor belonging to related to ABI3 and VP1 family, which is also known as ethylene response DNA-binding factor 1 and functions as a repressor of flowering in Arabidopsis. Here, a putative homolog of AtTEM1 was isolated and characterized from chrysanthemum, designated as CmTEM1. Exogenous application of ethephon leads to an upregulation in the expression of CmTEM1. Knockdown of CmTEM1 promotes floral initiation, while overexpression of CmTEM1 retards floral transition. Further phenotypic observations suggested that CmTEM1 involves in the ethylene-mediated inhibition of flowering. Transcriptomic analysis established that expression of the flowering integrator CmAFL1, a member of the APETALA1/FRUITFULL subfamily, was downregulated significantly in CmTEM1-overexpressing transgenic plants compared with wild-type plants but was verified to be upregulated in amiR-CmTEM1 lines by quantitative RT-PCR. In addition, CmTEM1 is capable of binding to the promoter of the CmAFL1 gene to inhibit its transcription. Moreover, the genetic evidence supported the notion that CmTEM1 partially inhibits floral transition by targeting CmAFL1. In conclusion, these findings demonstrate that CmTEM1 acts as a regulator of ethylene-mediated delayed flowering in chrysanthemum, partly through its interaction with CmAFL1.


Asunto(s)
Chrysanthemum , Proteínas de Plantas , Factores de Transcripción , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Chrysanthemum/fisiología , Etilenos/metabolismo , Flores/fisiología , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/metabolismo , Factores de Transcripción/metabolismo , Proteínas de Plantas/metabolismo
16.
Plant Sci ; 336: 111862, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37716191

RESUMEN

Homeodomain proteins encoded by BEL1- and KNAT1-type genes are ubiquitously distributed across plant species and play important roles in growth and development, whereby a comprehensive investigation of their molecular interactions and potential functions in wheat is of great significance. In this study, we systematically investigated the phylogenetic relationships, gene structures, conserved domains, and cis-acting elements of 34 TaBEL and 34 TaKNAT genes in the wheat genome. Our analysis revealed these genes evolved under different selective pressures and showed variable transcript levels in different wheat tissues. Subcellular localization analysis further indicated the proteins encoded by these genes were either exclusively located in the nucleus or both in the nucleus and the cytoplasm. Additionally, a comprehensive protein-protein interaction network was constructed with representative genes in which each TaBEL or TaKNAT proteins interact with at least two partners. The evaluation of wheat mutants identified key genes, including TaBEL-5B, TaBEL-4A.4, and TaKNAT6, which are involved in grain-related traits. Finally, haplotype analysis suggests TaKNAT-6B is associated with grain-related traits and is preferentially selected among a large set of wheat accessions. Our study provides important information on BEL1- and KNAT1-type gene families in wheat, and lays the foundation for functional research in the future.

17.
Biomed Pharmacother ; 167: 115580, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37776640

RESUMEN

Since the proposal of the neurovascular unit (NVU) theory, it has become almost mandatory for neuroprotective medicines against ischaemic stroke (IS) to focus on this unit. Refined Qingkailing (RQKL) is a compound composed of hyodeoxycholic acid, geniposide, baicalin and cholic acid, which has shown great potential in the treatment of IS, but its effect on NVU has not been fully studied. The purpose of this study was to investigate the potential biological pathways that underlie the protective effects of RQKL against NVU damage induced by oxygen-glucose deprivation and re-oxygenation (OGD/R). Using in vitro OGD/R models, we looked into whether RQKL protects the NVU. In order to create an in vitro NVU that resembles IS, we created an OGD/R injury model using primary cultures of brain microvascular endothelial cells, neurons, and astrocytes. Based on our results, we present evidence, for the first time, that RQKL treatment of the injury caused by OGD/R significantly (1) kept the blood brain barrier (BBB) functioning and maintained the architecture of the neurons, (2) mitigated the oxidative stress damage, inflammatory cytokine release, and neuronal death, and (3) upregulated the expression of neurotrophic factors generated from glial cells and the brain in the in vitro model. Therefore, RQKL has a variety of preventive effects against NVU damage caused by OGD/R. RQKL may be a suitable medication for treating IS in a clinical setting.


Asunto(s)
Isquemia Encefálica , Fármacos Neuroprotectores , Accidente Cerebrovascular , Humanos , Oxígeno/metabolismo , Isquemia Encefálica/metabolismo , Células Endoteliales , Glucosa/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/metabolismo
18.
IEEE Trans Cybern ; PP2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37747871

RESUMEN

This article presents an event-triggered adaptive NN command-filtered control for a class of multi-input and multi-output (MIMO) nonlinear systems with unknown rate-dependent hysteresis in the actuator and the constraints on full states. The ETM is used to reduce the communication frequency between controller and actuator. The command filter technique is first employed to solve the dilemma between the nondifferentiable control signal at triggering instants and rate-dependent hysteresis input premise while avoiding the "explosion of complexity" problem. During the backstepping design, the barrier Lyapunov functions are utilized to guarantee that system states will stay in certain regions and the unknown nonlinear items are approximated by adaptive neural networks. The compensating signals are constructed to eliminate filtering errors. The estimates of unknown hysteresis parameters are updated by adaptive laws. The stability analysis is given and the effectiveness of the proposed method is verified by simulation.

19.
ISA Trans ; 142: 420-426, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37544823

RESUMEN

This note shows an elegant relationship between the quadratic optimal control and robust stabilization for linear time-invariant (LTI) systems, where the former control can robustly stabilize the latter system, provided that the matched uncertainty is bounded. Through reviewing the relevant literature, some common mistakes in regard to this relationship are found. The correct results are obtained and proved in both frequency and time domains. The results are applicable to both single- and multi-input cases. They are significant as the simple LQR design for the nominal system can be utilized to directly solve-with no further effort-the complex robust stabilization problem for a class of linear uncertain systems.

20.
Artículo en Inglés | MEDLINE | ID: mdl-37459691

RESUMEN

Total glucosides picrorhizae rhizome (TGPR) is an innovative traditional Chinese medicine, which is a candidate drug for the treatment of nonalcoholic steatohepatitis (NASH). However, there is still lack of deep research on the behaviors of TGPR in vivo. In this study, a reliable, specific, and sensitive liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been constructed for simultaneous determination of picroside I, picroside II, vanillic acid, androsin, cinnamic acid and picroside IV, the major active constituents of TGPR, in rat various biological matrices (plasma, tissue, bile, urine and feces) using diphenhydramine hydrochloride and paeoniflorin as the internal standard. All biosamples were prepared using a simple protein precipitation with acetonitrile. Chromatographic separation was achieved on a waters UHPLC® HSS T3 (100×2.1 mm, 1.8 µm) column. The mobile phase consisted of methanol: acetonitrile1(1:1, V/V) and 0.5 mM ammonium formate in water, was employed to separate six components from endogenous interferences. The components were detected with a triple quadrupole mass spectrometer using positive and negative ion multiple reaction monitoring (MRM) mode. The newly developed method was successfully applied to investigate the pharmacokinetics, tissue distribution and excretion of six components in rats. The pharmacokinetic results indicated that the six components in TGPR could be quickly absorbed and slowly eliminated and their bioavailability were less than 12.37%, which implied the poor absorption after intragastric dosing. For tissue distribution, the six components in TGPR were detected in liver and only androsin could penetrate the blood-brain barrier. Meanwhile, the excretion study demonstrated that vanillic acid was mostly excreted as prototype drugs and the remaining five components might be widely metabolized in vivo as the metabolites, the unconverted form was excreted mainly by feces route. The pharmacokinetics, tissue distribution and excretion characteristics of six bioactive components in TGPR were firstly revealed, which will provide references for further clinical application of TGPR as an anti-NASH drug.


Asunto(s)
Medicamentos Herbarios Chinos , Espectrometría de Masas en Tándem , Ratas , Animales , Espectrometría de Masas en Tándem/métodos , Ratas Sprague-Dawley , Cromatografía Líquida de Alta Presión/métodos , Distribución Tisular , Medicamentos Herbarios Chinos/análisis , Rizoma/química , Ácido Vanílico/análisis , Glucósidos/farmacocinética
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