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1.
Nat Mater ; 23(5): 695-702, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38287128

RESUMO

π-Conjugated polymers (CPs) have broad applications in high-performance optoelectronics, energy storage, sensors and biomedicine. However, developing green and efficient methods to precisely synthesize alternating CP structures on a large scale remains challenging and critical for their industrialization. Here a room-temperature, scalable and homogeneous Suzuki-Miyaura-type polymerization reaction is developed with broad generality validated for 24 CPs including donor-donor, donor-acceptor and acceptor-acceptor connectivities, yielding device-quality polymers with high molecular masses. Furthermore, the polymerization protocol significantly reduces homocoupling structural defects, yielding more structurally regular and higher-performance electronic materials and optoelectronic devices than conventional thermally activated polymerizations. Experimental and theoretical studies reveal that a borate transmetalation process plays a key role in suppressing protodeboronation, which is critical for large-scale structural regularity. Thus, these results provide a general polymerization tool for the scalable production of device-quality CPs with alternating structural regularity.

2.
Am J Pathol ; 194(5): 735-746, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38382842

RESUMO

Twenty-five percent of cervical cancers are classified as endocervical adenocarcinomas (EACs), which comprise a highly heterogeneous group of tumors. A histopathologic risk stratification system known as the Silva pattern system was developed based on morphology. However, accurately classifying such patterns can be challenging. The study objective was to develop a deep learning pipeline (Silva3-AI) that automatically analyzes whole slide image-based histopathologic images and identifies Silva patterns with high accuracy. Initially, a total of 202 patients with EACs and histopathologic slides were obtained from Qilu Hospital of Shandong University for developing and internally testing the Silva3-AI model. Subsequently, an additional 161 patients and slides were collected from seven other medical centers for independent testing. The Silva3-AI model was developed using a vision transformer and recurrent neural network architecture, utilizing multi-magnification patches, and its performance was evaluated based on a class-specific area under the receiver-operating characteristic curve. Silva3-AI achieved a class-specific area under the receiver-operating characteristic curve of 0.947 for Silva A, 0.908 for Silva B, and 0.947 for Silva C on the independent test set. Notably, the performance of Silva3-AI was consistent with that of professional pathologists with 10 years' diagnostic experience. Furthermore, the visualization of prediction heatmaps facilitated the identification of tumor microenvironment heterogeneity, which is known to contribute to variations in Silva patterns.


Assuntos
Adenocarcinoma , Aprendizado Profundo , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/patologia , Redes Neurais de Computação , Curva ROC , Adenocarcinoma/patologia , Microambiente Tumoral
3.
FASEB J ; 38(13): e23765, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38934372

RESUMO

The importance of autophagy in atherosclerosis has garnered significant attention regarding the potential applications of autophagy inducers. However, the impact of TAT-Beclin1, a peptide inducer of autophagy, on the development of atherosclerotic plaques remains unclear. Single-cell omics analysis indicates a notable reduction in GAPR1 levels within fibroblasts, stromal cells, and macrophages during atherosclerosis. Tat-beclin1 (T-B), an autophagy-inducing peptide derived from Beclin1, could selectively bind to GAPR1, relieving its inhibition on Beclin1 and thereby augmenting autophagosome formation. To investigate its impact on atherosclerosic plaque progression, we established the ApoE-/- mouse model of carotid atherosclerotic plaques. Surprisingly, intravenous administration of Tat-beclin1 dramatically accelerated the development of carotid artery plaques. Immunofluorescence analysis suggested that macrophage aggregation and autophagosome formation within atherosclerotic plaques were significantly increased upon T-B treatment. However, immunofluorescence and transmission electron microscopy (TEM) analysis revealed a reduction in autophagy flux through lysosomes. In vitro, the interaction between T-B and GAPR1 was confirmed in RAW264.7 cells, resulting in the increased accumulation of p62/SQSTM1 and LC3-II in the presence of ox-LDL. Additionally, T-B treatment elevated the protein levels of p62/SQSTM1, LC3-II, and cleaved caspase 1, along with the secretion of IL-1ß in response to ox-LDL exposure. In summary, our study underscores that T-B treatment amplifies abnormal autophagy and inflammation, consequently exacerbating atherosclerotic plaque development in ApoE-/- mice.


Assuntos
Apolipoproteínas E , Aterosclerose , Autofagia , Proteína Beclina-1 , Placa Aterosclerótica , Animais , Camundongos , Proteína Beclina-1/metabolismo , Proteína Beclina-1/genética , Apolipoproteínas E/metabolismo , Apolipoproteínas E/deficiência , Aterosclerose/metabolismo , Aterosclerose/patologia , Autofagia/efeitos dos fármacos , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Células RAW 264.7 , Camundongos Endogâmicos C57BL , Masculino , Camundongos Knockout , Macrófagos/metabolismo
4.
Eur J Neurosci ; 59(11): 3045-3060, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38576168

RESUMO

Dual tasks (DTs) combining walking with a cognitive task can cause various levels of cognitive-motor interference, depending on which brain resources are recruited in each case. However, the brain activation and functional connectivity underlying cognitive-motor interferences remain to be elucidated. Therefore, this study investigated the neural correlation during different DT conditions in 40 healthy young adults (mean age: 27.53 years, 28 women). The DTs included walking during subtraction or N-Back tasks. Cognitive-motor interference was calculated, and brain activation and functional connectivity were analysed. Portable functional near-infrared spectroscopy was utilized to monitor haemodynamics in the prefrontal cortex (PFC), motor cortex and parietal cortex during each task. Walking interference (decrease in walking speed during DT) was greater than cognitive interference (decrease in cognitive performance during DT), regardless of the type of task. Brain activation in the bilateral PFC and parietal cortex was greater for walking during subtraction than for standing subtraction. Furthermore, brain activation was higher in the bilateral motor and parietal and PFCs for walking during subtraction than for walking alone, but only increased in the PFC for walking during N-Back. Coherence between the bilateral lateral PFC and between the left lateral PFC and left motor cortex was significantly greater for walking during 2-Back than for walking. The PFC, a critical brain region for organizing cognitive and motor functions, played a crucial role in integrating information coming from multiple brain networks required for completing DTs. Therefore, the PFC could be a potential target for the modulation and improvement of cognitive-motor functions during neurorehabilitation.


Assuntos
Cognição , Desempenho Psicomotor , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Feminino , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Masculino , Adulto , Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Adulto Jovem , Caminhada/fisiologia , Córtex Motor/fisiologia , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Lobo Parietal/fisiologia
5.
Small ; : e2400338, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38766952

RESUMO

0D hybrid metal halides (0D HMHs) with fully isolated inorganic units provide an ideal platform for studying the correlations between chiroptical activities and crystal structures at atomic levels. Here, through the incorporation of different solvent molecules, a series of 0D chiral manganese bromides (RR/SS-C20H28N2)3MnBr8·2X (X = C2H5OH, CH3OH, or H2O) are synthesized to elucidate their chiroptical properties. They show negligible circular dichroism signals of Mn absorptions due to C2v-symmetric [MnBr4]2- tetrahedra. However, they display distinct circularly polarized luminescence (CPL) signals with continuously increased luminescence asymmetry factors (glum) from 10-4 (X = C2H5OH) to 10-3 (X = H2O). The increased glum value is structurally revealed to originate from the enhancement of [MnBr4]2- tetrahedral bond-angle distortions, due to the presence of different solvent molecules. Furthermore, (RR/SS-C20H28N2)MnBr4·H2O enantiomers with larger bond-angle distortions of [MnBr4]2- tetrahedra are synthesized based on hydrobromic acid-induced structural transformation of (RR/SS-C20H28N2)3MnBr8·2H2O enantiomers. Therefore, such (RR/SS-C20H28N2)MnBr4·H2O enantiomers exhibit enhanced CPL signals with |glum| up to 1.23 × 10-2. This work provides unique insight into enhancing chiroptical activities in 0D HMH systems.

6.
Crit Rev Biotechnol ; 44(3): 337-351, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-36779332

RESUMO

ß-Carotene is one kind of the most important carotenoids. The major functions of ß-carotene include the antioxidant and anti-cardiovascular properties, which make it a growing market. Recently, the use of metabolic engineering to construct microbial cell factories to synthesize ß-carotene has become the latest model for its industrial production. Among these cell factories, yeasts including Saccharomyces cerevisiae and Yarrowia lipolytica have attracted the most attention because of the: security, mature genetic manipulation tools, high flux toward carotenoids using the native mevalonate pathway and robustness for large-scale fermentation. In this review, the latest strategies for ß-carotene biosynthesis, including protein engineering, promoters engineering and morphological engineering are summarized in detail. Finally, perspectives for future engineering approaches are proposed to improve ß-carotene production.


Assuntos
Engenharia Metabólica , Yarrowia , beta Caroteno/genética , beta Caroteno/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Saccharomyces cerevisiae/genética , Regiões Promotoras Genéticas
7.
Arch Virol ; 169(2): 26, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214770

RESUMO

Pigeons can be infected with various RNA viruses, and their innate immune system responds to viral infection to establish an antiviral response. Mitochondrial antiviral signaling protein (MAVS), an important adaptor protein in signal transduction, plays a pivotal role in amplifying the innate immune response. In this study, we successfully cloned pigeon MAVS (piMAVS) and performed a bioinformatics analysis. The results showed that the caspase recruitment domain (CARD) and transmembrane (TM) domain are highly conserved in poultry and mammals but poorly conserved in other species. Furthermore, we observed that MAVS expression is upregulated both in pigeons and pigeon embryonic fibroblasts (PEFs) upon RNA virus infection. Overexpression of MAVS resulted in increased levels of ß-interferon (IFN-ß), IFN-stimulated genes (ISGs), and interleukin (ILs) mRNA and inhibited Newcastle disease virus (NDV) replication. We also found that piMAVS and human MAVS (huMAVS) induced stronger expression of IFN-ß and ISGs when compared to chicken MAVS (chMAVS), and this phenomenon was also reflected in the degree of inhibition of NDV replication. Our findings demonstrate that piMAVS plays an important role in repressing viral replication by regulating the activation of the IFN signal pathway in pigeons. This study not only sheds light on the function of piMAVS in innate immunity but also contributes to a more comprehensive understanding of the innate immunity system in poultry. Our data also provide unique insights into the differences in innate immunity between poultry and mammal.


Assuntos
Columbidae , Imunidade Inata , Transdução de Sinais , Animais , Humanos , Antivirais , Interferon beta/genética , Interferon beta/metabolismo , Mamíferos , Vírus da Doença de Newcastle
8.
Nucleic Acids Res ; 50(17): 9632-9646, 2022 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-36043443

RESUMO

Adenine base editors (ABEs) catalyze A-to-G conversions, offering therapeutic options to treat the major class of human pathogenic single nucleotide polymorphisms (SNPs). However, robust and precise editing at diverse genome loci remains challenging. Here, using high-throughput chemical screening, we identified and validated SB505124, a selective ALK5 inhibitor, as an ABE activator. Treating cells with SB505124 enhanced on-target editing at multiple genome loci, including epigenetically refractory regions, and showed little effect on off-target conversion on the genome. Furthermore, SB505124 facilitated the editing of disease-associated genes in vitro and in vivo. Intriguingly, SB505124 served as a specific activator by selectively promoting ABE activity. Mechanistically, SB505124 promotes ABE editing, at least in part, by enhancing ABE expression and modulating DNA repair-associated genes. Our findings reveal the role of the canonical transforming growth factor-ß pathway in gene editing and equip ABEs with precise chemical control.


Assuntos
Adenina , Fator de Crescimento Transformador beta , Adenina/química , Sistemas CRISPR-Cas , Edição de Genes , Genoma , Humanos , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Fatores de Crescimento Transformadores/metabolismo
9.
Biotechnol Lett ; 46(1): 37-46, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38064043

RESUMO

Metabolic Engineering of yeast is a critical approach to improving the production capacity of cell factories. To obtain genetically stable recombinant strains, the exogenous DNA is preferred to be integrated into the genome. Previously, we developed a Golden Gate toolkit YALIcloneNHEJ, which could be used as an efficient modular cloning toolkit for the random integration of multigene pathways through the innate non-homologous end-joining repair mechanisms of Yarrowia lipolytica. We expanded the toolkit by designing additional building blocks of homologous arms and using CRISPR technology. The reconstructed toolkit was thus entitled YALIcloneHR and designed for gene-specific knockout and integration. To verify the effectiveness of the system, the gene PEX10 was selected as the target for the knockout. This system was subsequently applied for the arachidonic acid production, and the reconstructed strain can accumulate 4.8% of arachidonic acid. The toolkit will expand gene editing technology in Y. lipolytica, which would help produce other chemicals derived from acetyl-CoA in the future.


Assuntos
Sistemas CRISPR-Cas , Yarrowia , Sistemas CRISPR-Cas/genética , Yarrowia/genética , Yarrowia/metabolismo , Ácido Araquidônico/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Edição de Genes , Engenharia Metabólica
10.
Ecotoxicol Environ Saf ; 279: 116461, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38763051

RESUMO

Polystyrene nanoplastics (PS-NPs) have been reported to accumulate in the testes and constitute a new threat to reproductive health. However, the exact effects of PS-NPs exposure on testicular cells and the underlying mechanisms remain largely unknown. The C57BL/6 male mice were orally administered with PS-NPs (80 nm) at different dosages (0, 10, and 40 mg/kg/day) for 60 days, and GC-1 cells were treated with PS-NPs in this study. Enlarged seminiferous tubule lumens and a loose and vacuolated layer of spermatogenic cells were observed in PS-NPs-exposed mice. Spermatogenic cells which may be one of the target cells for this reproductive damage, were decreased in the mice from PS-NPs group. PS-NPs caused spermatogenic cells to undergo senescence, manifested as elevated SA-ß-galactosidase activity and activated senescence-related signaling p53-p21/Rb-p16 pathways, and induced cell cycle arrest. Mechanistically, Gene Ontology (GO) enrichment suggested the key role of reactive oxygen species (ROS) in PS-NPs-induced spermatogenic cell senescence, and this result was confirmed by measuring ROS levels. Moreover, ROS inhibition partially attenuated the senescence phenotype of spermatogenic cells and DNA damage. Using the male health atlas (MHA) database, Sirt1 was filtrated as the critical molecule in the regulation of testicular senescence. PS-NPs induced overexpression of the main ROS generator Nox2, downregulated Sirt1, increased p53 and acetylated p53 in vivo and in vitro, whereas these disturbances were partially restored by pterostilbene. In addition, pterostilbene intervention significantly alleviated the PS-NPs-induced spermatogenic cell senescence and attenuated ROS burst. Collectively, our study reveals that PS-NPs exposure can trigger spermatogenic cell senescence mediated by p53-p21/Rb-p16 signaling by regulating the Sirt1/ROS axis. Importantly, pterostilbene intervention may be a promising strategy to alleviate this damage.


Assuntos
Senescência Celular , Camundongos Endogâmicos C57BL , Poliestirenos , Espécies Reativas de Oxigênio , Sirtuína 1 , Animais , Masculino , Sirtuína 1/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Senescência Celular/efeitos dos fármacos , Camundongos , Poliestirenos/toxicidade , Testículo/efeitos dos fármacos , Testículo/patologia , Espermatogênese/efeitos dos fármacos , Nanopartículas/toxicidade , Dano ao DNA , Transdução de Sinais/efeitos dos fármacos
11.
Phytochem Anal ; 35(2): 239-253, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37779216

RESUMO

INTRODUCTION: Scutellaria baicalensis Georgi, a traditional Chinese medicine, is widely applied to treat various diseases among people, especially in East Asia. However, the specific active compounds in S. baicalensis aqueous extracts (SBAEs) responsible for the hypoglycemic and hypolipidemic properties as well as their potential mechanisms of action remain unclear. OBJECTIVES: This work aimed to explore the potential hypoglycemic and hypolipidemic compounds from SBAE and their potential mechanisms of action. METHODOLOGY: The in vitro inhibitory tests against lipase and α-glucosidase, and the effects of SBAE on glucose consumption and total triglyceride content in HepG2 cells were first performed to evaluate the hypoglycemic and hypolipidemic effects. Then, affinity ultrafiltration liquid chromatography-mass spectrometry (LC-MS) screening strategy with five drug targets, including α-glucosidase, α-amylase, protein tyrosine phosphatase 1B (PTP1B), lipase and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) was developed to screen out the potential active constituents from SBAE, and some representative active compounds were further validated. RESULTS: SBAE displayed noteworthy hypoglycemic and hypolipidemic properties, and 4, 10, 4, 8, and 8 potential bioactive components against α-amylase, α-glucosidase, PTP1B, HMGCR, and lipase were initially screened out, respectively. The interaction network was thus constructed between the potential bioactive compounds screened out and their corresponding drug targets. Among them, baicalein, wogonin, and wogonoside were revealed to possess remarkable hypoglycemic and hypolipidemic effects. CONCLUSION: The potential hypolipidemic and hypoglycemic bioactive compounds in SBAE and their mode of action were initially explored through ligand-target interactions by combining affinity ultrafiltration LC-MS strategy with five drug targets.


Assuntos
Scutellaria baicalensis , Ultrafiltração , Humanos , alfa-Glucosidases , Hipoglicemiantes/farmacologia , Lipase , alfa-Amilases
12.
Angew Chem Int Ed Engl ; 63(1): e202316348, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37970653

RESUMO

Structural dimensionality and electronic dimensionality play a crucial role in determining the type of excitonic emission in hybrid metal halides (HMHs). It is important but challenging to achieve free exciton (FE) emission in zero-dimensional (0D) HMHs based on the control over the electronic dimensionality. In this work, a quasi-0D HMH (C7 H15 N2 Br)2 PbBr4 with localized electronic dimensionality is prepared as a prototype model. With increasing pressure onto (C7 H15 N2 Br)2 PbBr4 , the broad and weak self-trapped exciton (STE) emission at ambient conditions is considerably enhanced before 3.6 GPa, which originates from more distorted [PbBr4 ]2- seesaw units upon compression. Notably, a narrow FE emission in (C7 H15 N2 Br)2 PbBr4 appears at 3.6 GPa, and then this FE emission is gradually strengthened up to 8.4 GPa. High pressure structural characterizations reveal that anisotropic contraction of (C7 H15 N2 Br)2 PbBr4 results in a noticeable reduction in the distance between adjacent [PbBr4 ]2- seesaw units, as well as an obvious enhancement of crystal stiffness. Consequently, the electronic connectivity in (C7 H15 N2 Br)2 PbBr4 is sufficiently promoted above 3.6 GPa, which is also supported with theoretical calculations. The elevation of electronic connectivity and enhanced stiffness together lead to pressure-induced FE emission and subsequent emission enhancement in quasi-0D (C7 H15 N2 Br)2 PbBr4 .

13.
Angew Chem Int Ed Engl ; 63(26): e202402343, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38639055

RESUMO

Localized excitation in traditional organic photocatalysts typically prevents the generation and extraction of photo-induced free charge carriers, limiting their activity enhancement under illumination. Here, we enhance delocalized photoexcitation of small molecular photovoltaic catalysts by weakening their electron-phonon coupling via rational fluoro-substitution. The optimized 2FBP-4F catalyst we develop here exhibits a minimized Huang-Rhys factor of 0.35 in solution, high dielectric constant and strong crystallization in the solid state. As a result, the energy barrier for exciton dissociation is decreased, and more importantly, polarons are unusually observed in 2FBP-4F nanoparticles (NPs). With the increased hole transfer efficiency and prolonged charge carrier lifetime highly related to enhanced exciton delocalization, the PM6 : 2FBP-4F heterojunction NPs at varied concentration exhibit much higher optimized photocatalytic activity (207.6-561.8 mmol h-1 g-1) for hydrogen evolution than the control PM6 : BP-4F and PM6 : 2FBP-6F NPs, as well as other reported photocatalysts under simulated solar light (AM 1.5G, 100 mW cm-2).

14.
J Am Chem Soc ; 145(16): 9118-9128, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37015020

RESUMO

The novel selenoviologen-based tetracationic cyclophanes (green boxes 3 and 5) with rigid electron-deficient cavities are synthesized via SN2 reactions in two steps. The green boxes exhibit good redox properties, narrow energy gaps, and strong absorption in the visible range (370-470 nm), especially for the green box 5 containing two selenoviologen (SeV2+) units. Meanwhile, the femtosecond transient absorption (fs-TA) reveals that the green boxes have a stabilized dicationic biradical, high efficiency of intramolecular charge transfer (ICT), and long-lived charge separation state due to the formation of cyclophane structure. Based on the excellent photophysical and redox properties, the green boxes are applied to electrochromic devices (ECDs) and visible-light-driven hydrogen production with a high H2 generation rate (34 µmol/h), turnover number (203), and apparent quantum yield (5.33 × 10-2). In addition, the host-guest recognitions are demonstrated between the green boxes and electron-rich guests (e.g., G1:1-naphthol and G2:platinum(II)-tethered naphthalene) in MeCN through C-H···π and π···π interactions. As a one-component system, the host-guest complexes of green box⊃G2 are successfully applied to visible-light photocatalytic hydrogen production due to the intramolecular electron transfer (IET) between platinum(II) of G2 and SeV2+ of the green box, which provides a simplified system for solar energy conversion.

15.
Chemistry ; 29(57): e202301968, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37486795

RESUMO

Self-assembly exploits noncovalent interaction to offer an effective method for the fabrication of materials. For Na9 [EuW10 O36 ] ⋅ 32H2 O (EuW10 ), the negative charges and abundant oxygen atoms on its surface provide a handle for static self-assembly. New properties are envisioned for EuW10 aggregates which are able to display such kinetics and time-programming characteristics, in order to satisfy more complex and intelligent application scenarios, such as DNA binding and information encryption. In this work, EuW10 coupling with stimuli-responsive dodecyl dimethylamine oxide (C12 DMAO) can generate versatile aggregates with pH-responsive properties. We demonstrated the temporal programming of the assembly and disassembly of EuW10 nanospheres using a pH clock reaction of acid/urease hydrolysis. The pH clock reaction endows EuW10 assemblies with dynamical properties, in which the charges and fluorescence changes are coded in this system. These fluorescent assemblies provide new application in time-programmed DNA capture and information encryption.

16.
Ann Bot ; 131(7): 1081-1095, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36661120

RESUMO

BACKGROUND AND AIMS: Growing evidence has suggested that plant responses to model soil microorganisms are context dependent; however, few studies have investigated the effects of whole soil microbial communities on plant performance in different abiotic and biotic conditions. To address this, we examined how soil phosphorus (P) availability and different planting patterns regulate soil microbial effects on the growth of two native plant species in a semiarid steppe. METHODS: We carried out a glasshouse experiment to explore the effects of the whole indigenous soil microbiota on the growth and performance of Leymus chinensis and Cleistogenes squarrosa using soil sterilization with different soil P availabilities and planting patterns (monoculture and mixture). Transcriptome sequencing (RNA-seq) was used to explain the potential molecular mechanisms of the soil microbial effects on C. squarrosa. KEY RESULTS: The soil sterilization treatment significantly increased the biomass of L. chinensis and C. squarrosa in both monoculture and mixture conditions, which indicated that the soil microbiota had negative growth effects on both plants. The addition of P neutralized the negative microbial effects for both L. chinensis and C. squarrosa, whereas the mixture treatment amplified the negative microbial effects on L. chinensis but alleviated them on C. squarrosa. Transcriptomic analysis from C. squarrosa roots underscored that the negative soil microbial effects were induced by the upregulation of defence genes. The P addition treatment resulted in significant decreases in the number of differentially expressed genes attributable to the soil microbiota, and some defence genes were downregulated. CONCLUSIONS: Our results underline that indigenous soil microbiota have negative effects on the growth of two dominant plant species from a semiarid steppe, but their effects are highly dependent on the soil P availability and planting patterns. They also indicate that defence genes might play a key role in controlling plant growth responses to the soil microbiota.


Assuntos
Fósforo , Solo , Microbiologia do Solo , Plantas , Poaceae/fisiologia
17.
Ethn Health ; 28(6): 809-821, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36803178

RESUMO

AIMS: This study examines: (a) the prevalence rate of type 2 diabetes mellitus (T2DM) in Chinese Americans (CAs); (b) the influence of acculturative status (i.e. generational status and linguistic fluency) on T2DM prevalence; (c) and differences in diabetes management between CAs and Non-Hispanic Whites (NHWs). METHODS: We used 2011-2018 data from the California Health Interview Survey (CHIS) to analyze the prevalence rate and management of diabetes among the CAs. Chi-squares, linear regressions, and logistic regressions were used to analyze the data. RESULTS: After controlling for demographic, socioeconomic, and health behaviors, there were no significant differences in the T2DM prevalence rate between CAs overall or of varying acculturative statuses compared with NHWs. However, there were differences in diabetes management, with first-generation CAs being less likely to exam glucose daily, have medical care plans developed by medical providers, or have confidence in controlling diabetes compared to NHWs. CAs with limited English proficiency (LEP) were less likely to perform self-monitoring of blood glucose or have confidence in managing their diabetes care compared to NHWs. Finally, non-first generation CAs were also more likely to take diabetes medication compared to NHWs. CONCLUSIONS: Although the prevalence rate of T2DM was found to be similar between CAs and NHWs, significant differences were found in diabetes care and management. Specifically, those who were less acculturated (e.g. first generation and those with LEP) were less likely to actively manage and have confidence in managing their T2DM. These results highlight the importance of targeting immigrants with LEP in prevention and intervention efforts.


Assuntos
Asiático , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , População do Leste Asiático , Etnicidade , Prevalência , Brancos , Estados Unidos/epidemiologia , Asiático/estatística & dados numéricos
18.
Sensors (Basel) ; 23(21)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37960523

RESUMO

Aiming at the problem of the low cooperative positioning accuracy and robustness of multi-UAV formation, a cooperative positioning method of a multi-UAV based on an adaptive fault-tolerant federated filter is proposed. Combined with the position of the follower UAV and leader UAV, and the relative range between them, a cooperative positioning model of the follower UAV is established. On this basis, an adaptive fault-tolerant federated filter is designed. Fault detection and isolation technology are added to improve the positioning accuracy of the follower UAV and the fault tolerance performance of the filter. Meanwhile, the measurement noise matrix is adjusted by the adaptive information allocation coefficient to reduce the impact of undetected fault information on the sub-filter and global estimation accuracy. The simulation results show that the adaptive fault-tolerant federated algorithm can greatly improve the positioning accuracy, which is 83.4% higher than that of the absolute positioning accuracy of a single UAV. In the case of a gradual fault, the method has a stronger fault-tolerant performance and reconstruction performance.

19.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834719

RESUMO

Pyranoanthocyanins have been reported to possess better chemical stability and bioactivities than monomeric anthocyanins in some aspects. The hypocholesterolemic activity of pyranoanthocyanins is unclear. In view of this, this study was conducted to compare the cholesterol-lowering activities of Vitisin A with the anthocyanin counterpart Cyanidin-3-O-glucoside(C3G) in HepG2 cells and to investigate the interaction of Vitisin A with the expression of genes and proteins associated with cholesterol metabolism. HepG2 cells were incubated with 40 µM cholesterol and 4 µM 25-hydroxycholeterol with various concentrations of Vitisin A or C3G for 24 h. It was found that Vitisin A decreased the cholesterol levels at the concentrations of 100 µM and 200 µM with a dose-response relationship, while C3G exhibited no significant effect on cellular cholesterol. Furthermore, Vitisin A could down-regulate 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMGCR) to inhibit cholesterol biosynthesis through a sterol regulatory element-binding protein 2 (SREBP2)-dependent mechanism, and up-regulate low-density lipoprotein receptor (LDLR) and blunt the secretion of proprotein convertase subtilisin/kexin type 9 (PCSK9) protein to promote intracellular LDL uptake without LDLR degradation. In conclusion, Vitisin A demonstrated hypocholesterolemic activity, by inhibiting cholesterol biosynthesis and enhancing LDL uptake in HepG2 cells.


Assuntos
Antocianinas , Pró-Proteína Convertase 9 , Humanos , Pró-Proteína Convertase 9/genética , Células Hep G2 , Colesterol/metabolismo , Receptores de LDL/metabolismo
20.
Int J Mol Sci ; 24(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37445682

RESUMO

Drug development for Alzheimer's disease, the leading cause of dementia, has been a long-standing challenge. Saponins, which are steroid or triterpenoid glycosides with various pharmacological activities, have displayed therapeutic potential in treating Alzheimer's disease. In a comprehensive review of the literature from May 2007 to May 2023, we identified 63 references involving 40 different types of saponins that have been studied for their effects on Alzheimer's disease. These studies suggest that saponins have the potential to ameliorate Alzheimer's disease by reducing amyloid beta peptide deposition, inhibiting tau phosphorylation, modulating oxidative stress, reducing inflammation, and antiapoptosis. Most intriguingly, ginsenoside Rg1 and pseudoginsenoside-F11 possess these important pharmacological properties and show the best promise for the treatment of Alzheimer's disease. This review provides a summary and classification of common saponins that have been studied for their therapeutic potential in Alzheimer's disease, showcasing their underlying mechanisms. This highlights the promising potential of saponins for the treatment of Alzheimer's disease.


Assuntos
Doença de Alzheimer , Saponinas , Humanos , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Saponinas/farmacologia , Saponinas/uso terapêutico , Proteínas tau
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