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1.
Phys Rev Lett ; 132(26): 266602, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38996328

RESUMO

Twisted moiré materials, a new class of layered structures with different twist angles for neighboring layers, are attracting great attention because of the rich intriguing physical phenomena associated with them. Of particular interest are the topological network modes, first proposed in the small angle twisted bilayer graphene under interlayer bias. Here we report the observations of such topological network modes in twisted moiré phononic crystals without requiring the external bias fields. Acoustic topological network modes that can be constructed in a wide range of twist angles are both observed in the domain walls with and without reconstructions, which serve as the analogy of the lattice relaxations in electronic moiré materials. Topological robustness of the topological network modes is observed by introducing valley-preserved defects to the network channel. Furthermore, the network can be reconfigured into two-dimensional patterns with any desired connectivity, offering a unique prototype platform for acoustic applications.

2.
J Org Chem ; 89(13): 9543-9550, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38874168

RESUMO

A visible-light-initiated C-H trifluoromethylation of quinoxalin-2(1H)-ones was established using a Z-scheme V2O5/g-C3N4 heterojunction as a recyclable photocatalyst in an inert atmosphere at room temperature under additive-free and mild conditions. A variety of trifluoromethylated quinoxalin-2-(1H)-one derivatives were heterogeneously generated in moderate to high yields, exhibiting good functional group tolerance. Remarkably, the recyclable V2O5/g-C3N4 catalyst could be reused five times with a slight loss of catalytic activity.

3.
Environ Res ; 248: 118250, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244964

RESUMO

The persistent O3 pollution in the Beijing-Tianjin-Hebei (BTH) region remains unresolved, largely due to limited comprehension of O3-precursor relationship and photochemistry drivers. In this work, intraday O3 sensitivity evolution from VOC-limited (volatile organic compound) regime in the forenoon to transition regime in the late afternoon was inferred by relative incremental reactivity (RIR) in summer 2019 at Xianghe, a suburban site in BTH region, suggesting that VOC-focused control policy could combine with stringent afternoon NOx control. Then detailed impacts of VOC subgroups on O3 formation were further comprehensively quantified by parametric OH reactivity (KOH), O3 formation potential (OFP), as well as RIR weighted value and O3 formation path tracing (OFPT) approach based on photochemical box model. O3 episode days corresponded to stronger O3 formation, depicted by higher KOH (10.4 s-1), OFP (331.7 µg m-3), RIR weighted value (1.2), and F(O3)-OFPT (15.5 ppbv h-1). High proportions of isoprene and OVOCs (oxygenated VOCs) to the total KOH and the OFPT method were demonstrated whereas results of OFP and RIR-weighted presented extra great impacts of aromatics on O3 formation. The OFPT approach captured the process that has already happened and included final O3 response to the original VOC, thus reliable for replicating VOC impacts. The comparison results of the four methods showed similarities when utilizing KOH and OFPT methods, which reveals that the potential applicability of simple KOH for contingency VOC control and more complex OFPT method for detailed VOC- and source-oriented control during policy-making. To investigate propulsion of VOC-involved O3 photochemistry, atmospheric oxidation capacity (AOC) was quantified by two atmospheric oxidation indexes (AOI). Both AOIp_G (7.0 × 107 molec cm-3 s-1, potential AOC calculated by oxidation reaction rates) and AOIe_G (8.5 µmol m-3, estimated AOC given redox electron transfer for oxidation products) were stronger on O3 episode days, indicating that AOC promoted the radical cycling initiated from VOC oxidation and subsequent O3 production. Result-oriented AOIe_G reasonably characterized actual AOC inferred by good linear correlation between AOIe_G and O3 concentrations compared to process-oriented AOIp_G. Therefore, with continuous NOx abatement, AOIe_G should be considered to represent actual AOC, also O3-inducing ability.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Ozônio/análise , Compostos Orgânicos Voláteis/análise , Monitoramento Ambiental , China , Oxirredução
4.
Alzheimers Dement ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38938161

RESUMO

INTRODUCTION: To investigate the role of a novel type of protein kinase C delta (PKCδ) in the neuroinflammation of Alzheimer's disease (AD). METHODS: We analyzed PKCδ and inflammatory cytokines levels in cerebrospinal fluid (CSF) of AD and normal controls, as well as their correlations. The cellular expression pattern of PKCδ and the effects of PKCδ modulation on microglia-mediated neuroinflammation were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), western blot, RNA sequencing (RNA-seq), and immunofluorescence staining. RESULTS: PKCδ levels were increased dramatically in the CSF of AD patients and positively correlated with cytokines. PKCδ is expressed mainly in microglia in the brain. Amyloid beta (Aß) stimulation increased PKCδ expression and secretion, which led to upregulation of the nuclear factor kappa B (NF-κB) pathway and overproduction of proinflammatory cytokines. Downregulation or inhibition of PKCδ attenuated Aß-induced microglial responses and improved cognitive function in an AD mouse model. DISCUSSION: Our study identifies PKCδ as a potential biomarker and therapeutic target for microglia-mediated neuroinflammation in AD. HIGHLIGHTS: Protein kinase C delta (PKCδ) levels increase in cerebrospinal fluid (CSF) of patients with Alzheimer's disease (AD), and positively correlate with elevated inflammatory cytokines in human subjects. PKCδ is expressed mainly in microglia in vivo, whereas amyloid beta (Aß) stimulation increases PKCδ expression and secretion, causing upregulation of the nuclear factor kappa B (NF-κB) pathway and production of inflammatory cytokines. Downregulation or inhibition of PKCδ attenuates Aß-enhanced NF-κB signaling and cytokine production in microglia and improves cognitive function in AD mice. PKCδ serves as a potential biomarker and therapeutic target for microglia-mediated neuroinflammation in AD.

5.
Int J Mol Sci ; 25(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38473826

RESUMO

Zearalenone (ZEA) is a common non-steroidal estrogenic mycotoxin found in a range of animal feeds and poses a serious threat to the reproductive health of farm animals and humans. However, the mechanism underlying ZEA-induced reproductive toxicity in sheep remains unknown. Granulosa cells are crucial for egg maturation and the fertility of female sheep. In this study, we aimed to examine the impact of different ZEA concentrations on sheep follicular granulosa cells and to elucidate the potential molecular mechanism underlying ZEA-induced toxicity using transcriptome sequencing and molecular biological approaches. Treating primary sheep follicular granulosa cells with different concentrations of ZEA promoted the overproduction of reactive oxygen species (ROS), increased lipid peroxidation products, led to cellular oxidative stress, decreased antioxidant enzyme activities, and induced cell apoptosis. Using transcriptome approaches, 1395 differentially expressed genes were obtained from sheep follicular granulosa cells cultured in vitro after ZEA treatment. Among them, heme oxygenase-1 (HMOX1) was involved in 11 biological processes. The protein interaction network indicated interactions between HMOX1 and oxidative and apoptotic proteins. In addition, N-acetylcysteine pretreatment effectively reduced the ZEA-induced increase in the expression of HMOX1 and Caspase3 by eliminating ROS. Hence, we suggest that HMOX1 is a key differential gene involved in the regulation of ZEA-induced oxidative stress and apoptosis in follicular granulosa cells. These findings provide novel insights into the prevention and control of mycotoxins in livestock.


Assuntos
Micotoxinas , Zearalenona , Humanos , Feminino , Animais , Ovinos , Zearalenona/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Heme Oxigenase-1/metabolismo , Estresse Oxidativo , Células da Granulosa/metabolismo , Antioxidantes/farmacologia , Micotoxinas/metabolismo , Apoptose
6.
Biochem Biophys Res Commun ; 645: 55-60, 2023 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-36680937

RESUMO

Chronic pain is frequently reported in clinical practice. Therefore, it is important to identify effective therapy to relieve pain. In this work, we selected Forsythoside B (FB), a phenylethanoid glycoside isolated from Forsythia suspensa (Thunb.) Vahl, to evaluate its effect in modulating inflammatory pain induced by complete Freund's adjuvant (CFA) and the involved mechanisms. We discovered that FB could attenuate inflammatory pain triggered by CFA injection and exert anti-anxiety effects. In detail, proinflammatory cytokines, consisting of IL-6 and TNF-α, were decreased after FB administration in the CFA-injected mice. Furthermore, the FB application ameliorated the activation of ionized calcium-binding adaptor molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP), the microglia and astrocytes markers respectively. Therefore, our findings indicate that FB could be a promising treatment for chronic inflammatory pain.


Assuntos
Dor Crônica , Inflamação , Camundongos , Animais , Adjuvante de Freund , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Dor Crônica/induzido quimicamente , Dor Crônica/tratamento farmacológico , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Hiperalgesia/metabolismo
7.
Opt Express ; 31(2): 2628-2643, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785272

RESUMO

Defects in the optical lens directly affect the scattering properties of the optical lens and decrease the performance of the optical element. Although machine vision instead of manual detection has been widely valued, the feature fusion technique of series operation and edge detection cannot recognize low-contrast and multi-scale targets in the lens. To address these challenges, in this study, an improved YOLOv5-C3CA-SPPF network model is proposed to detect defects on the surface and inside of the lens. The hybrid module combining the coordinate attention and CSPNet (C3) is incorporated into YOLOv5-C3CA for improving the extraction of target feature information and detection accuracy. Furthermore, an SPPF features fusion module is inserted into the neck of the network model to improve the detection accuracy of the network. To enhance the performance of supervised learning algorithms, a dataset containing a total of 3800 images is created, more than 600 images for each type of defect samples. The outcome of the experiment manifests that the mean average precision (mAP) of the YOLOv5-C3CA-SPPF algorithm is 97.1%, and the detection speed FPS is 41 f/s. Contrast to the traditional lens surface defects detection algorithms, YOLOv5-C3CA-SPPF can detect the types of optical lens surface and inside defects more accurately and quickly, the experimental results show that the YOLOv5-C3CA-SPPF model for identifying optical lens defects has good generalizability and robustness, which is favorable for on-line quality automatic detection of optical lens defects and provide an important guarantee for the quality consistency of finished products.

8.
Opt Express ; 31(16): 26610-26625, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710518

RESUMO

This paper outlines an experimental demonstration of a Bayesian image reconstruction approach to achieve rapid single-photon color imaging of moving objects. The capacity to extract the color of objects is important in a variety of target identification and computer vision applications. Nonetheless, it remains challenging to achieve high-speed color imaging of moving objects in low-photon flux environments. The low-photon regime presents particular challenges for efficient spectral separation and identification, while unsupervised image reconstruction algorithms are often slow and computationally expensive. In this paper, we address both of these difficulties using a combination of hardware and computational solutions. We demonstrate color imaging using a Single-Photon Avalanche Diode (SPAD) detector array for rapid, low-light-level data acquisition, with an integrated color filter array (CFA) for efficient spectral unmixing. High-speed image reconstruction is achieved using a bespoke Bayesian algorithm to produce high-fidelity color videos. The analysis is conducted first on simulated data allowing different pixel formats and photon flux scenarios to be investigated. Experiments are then performed using a plasmonic metasurface-based CFA, integrated with a 64 × 64 pixel format SPAD array. Passive imaging is conducted using white-light illumination of multi-colored, moving targets. Intensity information is recorded in a series of 2D photon-counting SPAD frames, from which accurate color information is extracted using the fast Bayesian method introduced herein. The per-frame reconstruction rate proves to be hundreds of times faster than the previous computational method. Furthermore, this approach yields additional information in the form of uncertainty measures, which can be used to assist with imaging system optimization and decision-making in real-world applications. The techniques demonstrated point the way towards rapid video-rate single-photon color imaging. The developed Bayesian algorithm, along with more advanced SPAD technology and utilization of time-correlated single-photon counting (TCSPC) will permit live 3D, color videography in extremely low-photon flux environments.

9.
Respir Res ; 24(1): 78, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36915149

RESUMO

BACKGROUND: Circular RNAs (circRNAs), a novel class of non-coding RNAs, play an important regulatory role in pulmonary arterial hypertension (PAH); however, the specific mechanism is rarely studied. In this study, we aimed to discover functional circRNAs and investigate their effects and mechanisms in hypoxia-induced pulmonary vascular remodelling, a core pathological change in PAH. METHODS: RNA sequencing was used to illustrate the expression profile of circRNAs in hypoxic PAH. Bioinformatics, Sanger sequencing, and quantitative real-time PCR were used to identify the ring-forming characteristics of RNA and analyse its expression. Then, we established a hypoxia-induced PAH mouse model to evaluate circRNA function in PAH by echocardiography and hemodynamic measurements. Moreover, microRNA target gene database screening, fluorescence in situ hybridisation, luciferase reporter gene detection, and western blotting were used to explore the mechanism of circRNAs. RESULTS: RNA sequencing identified 432 differentially expressed circRNAs in mouse hypoxic lung tissues. Our results indicated that circ-Ntrk2 is a stable cytoplasmic circRNA derived from Ntrk2 mRNA and frequently upregulated in hypoxic lung tissue. We further found that circ-Ntrk2 sponges miR-296-5p and miR-296-5p can bind to the 3'-untranslated region of transforming growth factor-ß1 (TGF-ß1) mRNA, thereby attenuating TGF-ß1 translation. Through gene knockout or exogenous expression, we demonstrated that circ-Ntrk2 could promote PAH and vascular remodelling. Moreover, we verified that miR-296-5p overexpression alleviated pulmonary vascular remodelling and improved PAH through the TGF-ß1/p38 MAPK pathway. CONCLUSIONS: We identified a new circRNA (circ-Ntrk2) and explored its function and mechanism in PAH, thereby establishing potential targets for the diagnosis and treatment of PAH. Furthermore, our study contributes to the understanding of circRNA in relation to PAH.


Assuntos
Hipertensão Pulmonar , MicroRNAs , Hipertensão Arterial Pulmonar , RNA Circular , Animais , Camundongos , Proliferação de Células , Hipertensão Pulmonar Primária Familiar , Hipertensão Pulmonar/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Hipertensão Arterial Pulmonar/genética , Receptor trkB , RNA Circular/genética , RNA Mensageiro , Fator de Crescimento Transformador beta1/genética , Remodelação Vascular/genética
10.
Mol Pharm ; 20(12): 6429-6440, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37903292

RESUMO

Endothelial cell damage is an important feature of preeclampsia (PE). Human umbilical mesenchymal stem-cell-derived extracellular vesicles (HUMSCs-derived EVs) have been shown to have therapeutic effects on a variety of diseases and tissue damage. However, the therapeutic effect of HUMSCs-derived EVs on endothelial injury in PE remains unclear. This study explored the possible mechanism of HUMSCs-derived EVs in the treatment of endothelial cell injury. Tumor necrosis factor α- and lipopolysaccharide-induced endothelial dysfunction models were used to evaluate the therapeutic effect of HUMSCs-derived EVs on endothelial injury. We further constructed PE mouse models to explore the function of HUMSCs-derived EVs in vivo. The changes of metabolites in endothelial cells after HUMSCs-derived EVs treatment were analyzed by metabolomics analysis and further validated by cell experiments. HUMSCs-derived EVs treatment can alleviate endothelial cell injury in PE, involving cell proliferation, migration, angiogenesis, and anti-inflammatory. Importantly, administration of HUMSCs-derived EVs improves hypertension and proteinuria in PE mice, alleviates kidney damage, and promotes vascularization in the placenta. Furthermore, metabolomics analysis found that the arginine metabolic pathway is activated after HUMSCs-derived EVs treatment. We also observed increased arginine level, nitric oxide content, and nitric oxide synthase activity, and further experiments proved that activating the arginine metabolic pathway could alleviate endothelial dysfunction. Our results reveal that HUMSCs-derived EVs could ameliorate PE endothelial dysfunction by activating the arginine metabolic pathway and may serve as a therapeutic method for treating PE.


Assuntos
Vesículas Extracelulares , Pré-Eclâmpsia , Gravidez , Feminino , Humanos , Camundongos , Animais , Pré-Eclâmpsia/terapia , Pré-Eclâmpsia/metabolismo , Células Endoteliais , Vesículas Extracelulares/metabolismo , Cordão Umbilical , Arginina
11.
Crit Rev Food Sci Nutr ; : 1-16, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37632418

RESUMO

Milk fat globule membrane (MFGM) is a complex trilayer structure present in mammalian milk and is mainly composed of phospholipids and proteins (>90%). Many studies revealed MFGM has positive effects on the immune system, brain development, and cognitive function of infants. Probiotics are live microorganisms that have been found to improve mental health and insulin sensitivity, regulate immunity, and prevent allergies. Probiotics are unstable and prone to degradation by environmental, processing, and storage conditions. In this review, the processes used for encapsulation of probiotics particularly the potential of MFGM and its constituents as encapsulating materials for probiotics are described. This study analyzes the importance of MFGM in encapsulating bioactive substances and emphasizes the interaction with probiotics and the gut as well as its resistance to adverse environmental factors in the digestive system when used as a probiotic embedding material. MFGM can enhance the gastric acid resistance and bile resistance of probiotics, mainly manifested in the survival rate of probiotics. Due to the role of digestion, MFGM-coated probiotics can be released in the intestine, and due to the biocompatibility of the membrane, it can promote the binding of probiotics to intestinal epithelial cells, and promote the colonization of some probiotics in the intestine.

12.
Environ Res ; 216(Pt 4): 114812, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36395862

RESUMO

Water quality parameters (WQP) are the most intuitive indicators of the environmental quality of water body. Due to the complexity and variability of the chemical environment of water body, simple and rapid detection of multiple parameters of water quality becomes a difficult task. In this paper, spectral images (named SPIs) and deep learning (DL) techniques were combined to construct an intelligent method for WQP detection. A novel spectroscopic instrument was used to obtain SPIs, which were converted into feature images of water chemistry and then combined with deep convolutional neural networks (CNNs) to train models and predict WQP. The results showed that the method of combining SPIs and DL has high accuracy and stability, and good prediction results with average relative error of each parameter (anions and cations, TOC, TP, TN, NO3--N, NH3-N) at 1.3%, coefficient of determination (R2) of 0.996, root mean square error (RMSE) of 0.1, residual prediction deviation (RPD) of 16.2, and mean absolute error (MAE) of 0.067. The method can achieve rapid and accurate detection of high-dimensional water quality multi-parameters, and has the advantages of simple pre-processing and low cost. It can be applied not only to the intelligent detection of environmental waters, but also has the potential to be applied in chemical, biological and medical fields.


Assuntos
Técnicas de Química Analítica , Monitoramento Ambiental , Qualidade da Água , Redes Neurais de Computação , Análise Espectral , Monitoramento Ambiental/métodos , Técnicas de Química Analítica/métodos
13.
Appl Opt ; 62(33): 8869-8881, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38038033

RESUMO

A lens defect is a common quality issue that has seriously harmed the scattering characteristics and performance of optical elements, reducing the quality consistency of the finished products. Furthermore, the energy hotspots coming from the high-energy laser through diffraction of optical component defects are amplified step by step in multi-level laser conduction, causing serious damage to the optical system. Traditional manual detection mainly relies on experienced workers under a special light source environment with high labor intensity, low efficiency, and accuracy. The common machine vision techniques are incapable of detecting low contrast and complex morphological defects. To address these challenges, a deep learning-based method, named STMask R-CNN, is proposed to detect defects on the surface and inside of a lens in complex environments. A Swin Transformer, which focuses on improving the modeling and representation capability of the features in order to improve the detection performance, is incorporated into the Mask R-CNN in this case. A challenge dataset containing more than 3800 images (18000 defect sample targets) with five different types of optical lens defects was created to verify the proposed approach. According to our experiments, the presented STMask R-CNN reached a precision value of 98.2%, recall value of 97.7%, F1 score of 97.9%, mAP@0.5 value of 98.1%, and FPS value of 24 f/s, which outperformed the SSD, Faster R-CNN, and YOLOv5. The experimental results demonstrated that the proposed STMask R-CNN outperformed other popular methods for multiscale targets, low contrast target detection and nesting, stacking, and intersecting defects sample detection, exhibiting good generalizability and robustness, as well as detection speed to meet mechanical equipment production efficiency requirements. In general, this research offers a favorable deep learning-based method for real-time automatic detection of optical lens defects.

14.
Arch Gynecol Obstet ; 308(2): 319-339, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-35916961

RESUMO

INTRODUCTION: Despite intensive research, preterm birth (PTB) rates have not decreased significantly in recent years due to a lack of understanding of the underlying causes and insufficient treatment options for PTB. We are committed to finding promising biomarkers for the treatment of PTB. METHODS: An extensive search of the literature was conducted with MEDLINE/PubMed, and in total, 151 studies were included and summarized in the present review. RESULTS: Substantial evidence supports that the infection and/or inflammatory cascade associated with infection is an early event in PTB. Toll-like receptor (TLR) is a prominent pattern recognition receptor (PRR) found on both immune and non-immune cells, including fetal membrane cells. The activation of TLR downstream molecules, followed by TLR binding to its ligand, is critical for infection and inflammation, leading to the involvement of the TLR signaling pathway in PTB. TLR ligands are derived from microbial components and molecules released by damaged and dead cells. Particularly, TLR4 is an essential TLR because of its ability to recognize lipopolysaccharide (LPS). In this comprehensive overview, we discuss the role of TLR signaling in PTB, focus on numerous host-derived genetic and epigenetic regulators of the TLR signaling pathway, and cover ongoing research and prospective therapeutic options for treating PTB by inhibiting TLR signaling. CONCLUSION: This is a critical topic because TLR-related molecules and mechanisms may enable obstetricians to better understand the physiological changes in PTB and develop new treatment and prevention strategies.


Assuntos
Nascimento Prematuro , Feminino , Recém-Nascido , Humanos , Nascimento Prematuro/etiologia , Receptores Toll-Like/metabolismo , Transdução de Sinais , Inflamação , Ligantes
15.
Bioprocess Biosyst Eng ; 46(4): 611-620, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36735093

RESUMO

This work aimed to study the efficiency of nano- and micro- fiber membranes in immobilizing Actinobacillus succinogenes CCTCC M2012036 for succinic acid production. Among the four kinds of electrospun nanofiber membranes of cellulose acetate, chitosan, poly(vinyl alcohol) (PVA) and chitosan-PVA, the cellulose acetate nanofiber membrane-immobilized cells performed the best with a succinic acid concentration and yield to be 27.3 ± 3.5 g/L and 70.9 ± 5.8%. The cell-immobilized viscose microfiber membrane presented good reuse stability, and 17 batches of fermentation without activity loss were realized with the highest succinic acid yield of 83.20%. A microfiber membrane bioreactor was further constructed with the cell-immobilized viscose microfiber membrane to perform fermentation on a larger scale, and the concentration, yield and productivity of succinic acid were 73.20 g/L, 86.50% and 1.49 g/(L⋅h) using a fed-batch strategy, which were 124.30%, 127.60% and 124.2% of those obtained in the traditional fermenter. This study provided an approach for improving the practicality of biological succinic acid production.


Assuntos
Actinobacillus , Quitosana , Ácido Succínico , Reatores Biológicos , Fermentação
16.
Int J Mol Sci ; 24(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36982707

RESUMO

Thermophilic cyanobacteria are cosmopolitan and abundant in the thermal environment. Their light-harvesting complexes, phycobilisomes (PBS), are highly important in photosynthesis. To date, there is limited information on the PBS composition of thermophilic cyanobacteria whose habitats are challenging for survival. Herein, genome-based methods were used to investigate the molecular components of PBS in 19 well-described thermophilic cyanobacteria. These cyanobacteria are from the genera Leptolyngbya, Leptothermofonsia, Ocullathermofonsia, Thermoleptolyngbya, Trichothermofonsia, Synechococcus, Thermostichus, and Thermosynechococcus. According to the phycobiliprotein (PBP) composition of the rods, two pigment types are observed in these thermophiles. The amino acid sequence analysis of different PBP subunits suggests several highly conserved cysteine residues in these thermophiles. Certain amino acid contents in the PBP of thermophiles are significantly higher than their mesophilic counterparts, highlighting the potential roles of specific substitutions of amino acid in the adaptive thermostability of light-harvesting complexes in thermophilic cyanobacteria. Genes encoding PBS linker polypeptides vary among the thermophiles. Intriguingly, motifs in linker apcE indicate a photoacclimation of a far-red light by Leptolyngbya JSC-1, Leptothermofonsia E412, and Ocullathermofonsia A174. The composition pattern of phycobilin lyases is consistent among the thermophiles, except for Thermostichus strains that have extra homologs of cpcE, cpcF, and cpcT. In addition, phylogenetic analyses of genes coding for PBPs, linkers, and lyases suggest extensive genetic diversity among these thermophiles, which is further discussed with the domain analyses. Moreover, comparative genomic analysis suggests different genomic distributions of PBS-related genes among the thermophiles, indicating probably various regulations of expression. In summary, the comparative analysis elucidates distinct molecular components and organization of PBS in thermophilic cyanobacteria. These results provide insights into the PBS components of thermophilic cyanobacteria and fundamental knowledge for future research regarding structures, functions, and photosynthetic improvement.


Assuntos
Cianobactérias , Ficobilissomas , Ficobilissomas/genética , Ficobilissomas/metabolismo , Filogenia , Cianobactérias/genética , Cianobactérias/metabolismo , Ficobilinas , Complexos de Proteínas Captadores de Luz/genética , Proteínas de Bactérias/metabolismo
17.
Int J Mol Sci ; 24(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36902202

RESUMO

Δ12-fatty acid dehydrogenase (FAD2) is the essential enzyme responsible for catalyzing the formation of linoleic acid from oleic acid. CRISPR/Cas9 gene editing technology has been an essential tool for molecular breeding in soybeans. To evaluate the most suitable type of gene editing in soybean fatty acid synthesis metabolism, this study selected five crucial enzyme genes of the soybean FAD2 gene family-GmFAD2-1A, GmFAD2-1B, GmFAD2-2A, GmFAD2-2B, and GmFAD2-2C-and created a CRISPR/Cas9-mediated single gene editing vector system. The results of Sanger sequencing showed that 72 transformed plants positive for T1 generation were obtained using Agrobacterium-mediated transformation, of which 43 were correctly edited plants, with the highest editing efficiency of 88% for GmFAD2-2A. The phenotypic analysis revealed that the oleic acid content of the progeny of GmFAD2-1A gene-edited plants had a higher increase of 91.49% when compared to the control JN18, and the rest of the gene-edited plants in order were GmFAD2-2A, GmFAD2-1B, GmFAD2-2C, and GmFAD2-2B. The analysis of gene editing type has indicated that base deletions greater than 2bp were the predominant editing type in all editing events. This study provides ideas for the optimization of CRISPR/Cas9 gene editing technology and the development of new tools for precise base editing in the future.


Assuntos
Ácidos Graxos Dessaturases , Edição de Genes , Glycine max , Plantas Geneticamente Modificadas , Sistemas CRISPR-Cas , Ácidos Graxos Dessaturases/genética , Ácidos Graxos/metabolismo , Edição de Genes/métodos , Ácido Oleico/metabolismo , Plantas Geneticamente Modificadas/genética , Glycine max/genética
18.
Int J Mol Sci ; 24(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36769078

RESUMO

AP3 has been studied and is reported to affect structural changes in floral organs in various plants. However, the function of the soybean AP3 genes in flower development is unknown. Here, the full-length cDNA sequence of GmAP3 was obtained by RACE and it was verified that it belongs to the MADS-box subfamily by a bioinformatics analysis. The expression of GmAP3 is closely related to the expression of essential enzyme genes related to flower development. Yeast two-hybrid assays demonstrated that GmAP3 interacts with AP1 to determine the identity of flower organ development. A follow-up analysis showed that overexpression of the GmAP3 gene advanced flowering time and resulted in changes in floral organ morphology. The average flowering time of overexpressed soybean and tobacco plants was 6-8 days earlier than that of wild-type plants, and the average flowering time of gene-edited soybean and tobacco plants was 6-11 days later than that of wild-type plants. In conclusion, GmAP3 may directly or indirectly affect the flower development of soybean. The results of this study lay the foundation for further research on the biological functions of MADS transcriptional factors in soybeans.


Assuntos
Glycine max , Proteínas de Domínio MADS , Glycine max/metabolismo , Proteínas de Domínio MADS/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/metabolismo , Fatores de Transcrição/metabolismo , Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia
19.
Geriatr Nurs ; 54: 219-228, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37844538

RESUMO

BACKGROUND: Xerosis cutis in older adults is a geriatric public health issue that severely affects healthy aging, associated with adverse outcomes and increased nursing burden. Skin care plays a significant role in the management of xerosis cutis. AIM: To assess the pooled prevalence and interventions of xerosis cutis among older adults. METHODS: We searched ten databases systematically from inception to August 29, 2023. We estimated pooled prevalence of xerosis cutis using Stata 15.0. RESULTS: 28 articles were included in this review. The pooled prevalence of xerosis cutis was 53 %(95 %CI:36-69 %). We found the prevalence of xerosis cutis was highest in nursing homes and developed countries. The prevalence of xerosis cutis was similar in males and females. The prevalence of mild xerosis cutis and xerosis cutis at lower limbs was relatively high. Regular use of humectant-containing leave-on skin care products and structured skin care regimens were helpful in alleviating xerosis cutis. CONCLUSION: Older adults are at high risk for xerosis cutis. The research provides health professionals with a basic framework for the prevention and management of xerosis cutis.


Assuntos
Dermatopatias , Masculino , Feminino , Humanos , Idoso , Prevalência , Dermatopatias/epidemiologia , Dermatopatias/terapia , Casas de Saúde , Higiene da Pele
20.
BMC Plant Biol ; 22(1): 110, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277127

RESUMO

BACKGROUND: The plant architecture traits of maize determine the yield. Plant height, ear position, leaf angle above the primary ear and internode length above the primary ear together determine the canopy structure and photosynthetic efficiency of maize and at the same time affect lodging and disease resistance. A flat and tall plant architecture confers an obvious advantage in the yield of a single plant but is not conducive to dense planting and results in high rates of lodging; thus, it has been gradually eliminated in production. Although using plants that are too compact, short and density tolerant can increase the yield per unit area to a certain extent, the photosynthetic efficiency of such plants is low, ultimately limiting yield increases. Genetic mapping is an effective method for the improvement of plant architecture to identify candidate genes for regulating plant architecture traits. RESULTS: To find the best balance between the yield per plant and the yield per unit area of maize, in this study, the F2:3 pedigree population and a RIL population with the same male parent were used to identify QTL for plant height (PH), ear height (EH), leaf angle and internode length above the primary ear (LAE and ILE) in Changchun and Gongzhuling for 5 consecutive years (2016-2020). A total of 11, 13, 23 and 13 QTL were identified for PH, EH, LAE, and ILE, respectively. A pleiotropic consistent QTL for PH overlapped with that for EH on chromosome 3, with a phenotypic variation explanation rate from 6.809% to 21.96%. In addition, there were major consistent QTL for LAE and ILE, and the maximum phenotypic contribution rates were 24.226% and 30.748%, respectively. Three candidate genes were mined from the three consistent QTL regions and were involved in the gibberellin-activated signal pathway, brassinolide signal transduction pathway and auxin-activated signal pathway, respectively. Analysis of the expression levels of the three genes showed that they were actively expressed during the jointing stage of vigorous maize growth. CONCLUSIONS: In this study, three consistent major QTL related to plant type traits were identified and three candidate genes were screened. These results lay a foundation for the cloning of related functional genes and marker-assisted breeding of related functional genes.


Assuntos
Mapeamento Cromossômico , Estudos de Associação Genética , Fenótipo , Locos de Características Quantitativas , Zea mays/anatomia & histologia , Zea mays/genética , Produtos Agrícolas/anatomia & histologia , Produtos Agrícolas/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Variação Genética , Genótipo
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