Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
J Mater Chem B ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38716615

RESUMO

The healing of scalded wounds faces many challenges such as chronic inflammation, oxidative stress, wound infection, and difficulties in vascular and nerve regeneration. Treating a single problem cannot effectively coordinate the complex regenerative microenvironment of scalded wounds, limiting the healing and functional recovery of the skin. Therefore, there is a need to develop a multi-effect treatment plan that can adaptively address the issues at each stage of wound healing. In this study, we propose a scheme for on-demand release of hydrogen sulfide (H2S) based on the concentration of reactive oxygen species (ROS) in the wound microenvironment. This is achieved by encapsulating peroxythiocarbamate (PTCM) in the ROS-responsive polymer poly(ethylene glycol)-poly(L-methionine) (PMet) to form nanoparticles, which are loaded into a thermosensitive injectable hydrogel, F127-poly(L-aspartic acid-N-hydroxysuccinimide) (F127-P(Asp-NHS)), to create a scald dressing. The H2S released by the hydrogel dressing on demand regulates the wound microenvironment by alleviating infection, reducing oxidative stress, and remodeling inflammation, thereby accelerating the healing of full-thickness scalded wounds. This hydrogel dressing for the adaptive release of H2S has great potential in addressing complex scalded wounds associated with infection and chronic inflammation.

2.
Bioact Mater ; 38: 181-194, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38711758

RESUMO

Chronic diabetic wounds are the most common complication for diabetic patients. Due to high oxidative stress levels affecting the entire healing process, treating diabetic wounds remains a challenge. Here, we present a strategy for continuously regulating oxidative stress microenvironment by the catalyst-like magnesium-gallate metal-organic framework (Mg-GA MOF) and developing sprayable hydrogel dressing with sodium alginate/chitosan quaternary ammonium salts to treat diabetic wounds. Chitosan quaternary ammonium salts with antibacterial properties can prevent bacterial infection. The continuous release of gallic acid (GA) effectively eliminates reactive oxygen species (ROS), reduces oxidative stress, and accelerates the polarization of M1-type macrophages to M2-type, shortening the transition between inflammation and proliferative phase and maintaining redox balance. Besides, magnesium ions adjuvant therapy promotes vascular regeneration and neuronal formation by activating the expression of vascular-associated genes. Sprayable hydrogel dressings with antibacterial, antioxidant, and inflammatory regulation rapidly repair diabetic wounds by promoting neurovascular network reconstruction and accelerating re-epithelialization and collagen deposition. This study confirms the feasibility of catalyst-like MOF-contained sprayable hydrogel to regulate the microenvironment continuously and provides guidance for developing the next generation of non-drug diabetes dressings.

4.
Adv Healthc Mater ; : e2400770, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626942

RESUMO

Metabolites, as markers of phenotype at the molecular level, can regulate the function of DNA, RNA, and proteins through chemical modifications or interactions with large molecules. Citrate is an important metabolite that affects macrophage polarization and osteoporotic bone function. Therefore, a better understanding of the precise effect of citrate on macrophage polarization may provide an effective alternative strategy to reverse osteoporotic bone metabolism. In this study, a citrate functional scaffold to control the metabolic pathway during macrophage polarization based on the metabolic differences between pro-inflammatory and anti-inflammatory phenotypes for maintaining bone homeostasis, is fabricated. Mechanistically, only outside M1 macrophages are accumulated high concentrations of citrate, in contrast, M2 macrophages consume massive citrate. Therefore, citrate-functionalized scaffolds exert more sensitive inhibitory effects on metabolic enzyme activity during M1 macrophage polarization than M2 macrophage polarization. Citrate can block glycolysis-related enzymes by occupying the binding-site and ensure sufficient metabolic flux in the TCA cycle, so as to turn the metabolism of macrophages to oxidative phosphorylation of M2 macrophage, largely maintaining bone homeostasis. These studies indicate that exogenous citrate can realize metabolic control of macrophage polarization for maintaining bone homeostasis in osteoporosis.

5.
J Neurosci Methods ; 406: 110132, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604523

RESUMO

BACKGROUND: Traditional therapist-based rehabilitation training for patients with movement impairment is laborious and expensive. In order to reduce the cost and improve the treatment effect of rehabilitation, many methods based on human-computer interaction (HCI) technology have been proposed, such as robot-assisted therapy and functional electrical stimulation (FES). However, due to the lack of active participation of brain, these methods have limited effects on the promotion of damaged nerve remodeling. NEW METHOD: Based on the neurofeedback training provided by the combination of brain-computer interface (BCI) and exoskeleton, this paper proposes a multimodal brain-controlled active rehabilitation system to help improve limb function. The joint control mode of steady-state visual evoked potential (SSVEP) and motor imagery (MI) is adopted to achieve self-paced control and thus maximize the degree of brain involvement, and a requirement selection function based on SSVEP design is added to facilitate communication with aphasia patients. COMPARISON WITH EXISTING METHODS: In addition, the Transformer is introduced as the MI decoder in the asynchronous online BCI to improve the global perception of electroencephalogram (EEG) signals and maintain the sensitivity and efficiency of the system. RESULTS: In two multi-task online experiments for left hand, right hand, foot and idle states, subject achieves 91.25% and 92.50% best accuracy, respectively. CONCLUSION: Compared with previous studies, this paper aims to establish a high-performance and low-latency brain-controlled rehabilitation system, and provide an independent and autonomous control mode of the brain, so as to improve the effect of neural remodeling. The performance of the proposed method is evaluated through offline and online experiments.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Exoesqueleto Energizado , Neurorretroalimentação , Humanos , Eletroencefalografia/métodos , Masculino , Neurorretroalimentação/métodos , Neurorretroalimentação/instrumentação , Potenciais Evocados Visuais/fisiologia , Adulto , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Feminino , Adulto Jovem , Imaginação/fisiologia , Imagens, Psicoterapia/métodos
6.
J Control Release ; 370: 210-229, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38648955

RESUMO

Chronic skin wounds, especially infected ones, pose a significant clinical challenge due to their increasing incidence and poor outcomes. The deteriorative microenvironment in such wounds, characterized by reduced extracellular matrix, impaired angiogenesis, insufficient neurogenesis, and persistent bacterial infection, has prompted the exploration of novel therapeutic strategies. In this study, we developed an injectable multifunctional hydrogel (GEL/BG@Cu + Mg) incorporating Gelatin-Tannic acid/ N-hydroxysuccinimide functionalized polyethylene glycol and Bioactive glass doped with copper and magnesium ions to accelerate the healing of infected wounds. The GEL/BG@Cu + Mg hydrogel composite demonstrates good biocompatibility, degradability, and rapid formation of a protective barrier to stop bleeding. Synergistic bactericidal effects are achieved through the photothermal properties of BG@Cu + Mg and sustained copper ions release, with the latter further promoting angiogenesis. Furthermore, the hydrogel enhances neurogenesis by stimulating axons and Schwann cells in the wound bed through the beneficial effects of magnesium ions. Our results demonstrate that the designed novel multifunctional hydrogel holds tremendous promise for treating infected wounds and allowing regenerative neurogenesis at the wound site, which provides a viable alternative for further improving clinical outcomes.

7.
ACS Appl Mater Interfaces ; 16(13): 15687-15700, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38511302

RESUMO

Polyethylene terephthalate (PET) artificial ligaments, renowned for their superior mechanical properties, have been extensively adopted in anterior cruciate ligament (ACL) reconstruction surgeries. However, the inherent bio-inertness of PET introduces formidable barriers to graft-bone integration, a critical aspect of rehabilitation. Previous interventions, ranging from surface roughening to chemical modifications, have aimed to address this challenge; however, consistently effective techniques for inducing graft-bone integration remain scarce. Our study employed advanced surface-coating methodologies to introduce strontium-doped hydroxyapatite (SrHA) onto PET ligaments. Detailed scanning electron microscopy (SEM) examinations revealed a uniform and integrative coating of SrHA on PET fibers. Furthermore, spectroscopic analysis confirmed the steady release of strontium ions from the coated surface under physiological conditions. In-depth cellular studies proved that extracellular strontium emanating from SrHA-coated PET (PET@SrHA) ligaments actively steers the M2 macrophage polarization. Additionally, macrophages (Mφs) manifested a heightened secretion of prohealing cytokines when exposed to PET@SrHA. Subsequent investigations showed that these cytokines acted as mediators, activating integrin signaling pathways among macrophages, vascular endothelial cells, and osteoblasts. As a direct consequence, an increased rate of angiogenesis and osteogenic differentiation was observed, vital for graft-bone integration following ACL reconstruction with PET@SrHA ligaments. From a biochemical standpoint, our results pinpoint strontium ions as influential immunomodulators, sculpting the graft-bone interface's immune environment. This insight presents the SrHA-coating technique as a viable therapeutic strategy, holding sound promise for improving angiogenesis and osseointegration outcomes during ACL reconstruction using PET-based grafts.


Assuntos
Integrinas , Osteogênese , Citocinas , Angiogênese , Células Endoteliais , Hidroxiapatitas/química , Estrôncio/farmacologia , Estrôncio/química , Transdução de Sinais , Íons/farmacologia
8.
IEEE J Biomed Health Inform ; 28(5): 2624-2635, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38335090

RESUMO

The power spectra estimated from the brain recordings are the mixed representation of aperiodic transient activity and periodic oscillations, i.e., aperiodic component (AC) and periodic component (PC). Quantitative neurophysiology requires precise decomposition preceding parameterizing each component. However, the shape, statistical distribution, scale, and mixing mechanism of AC and PCs are unclear, challenging the effectiveness of current popular parametric models such as FOOOF, IRASA, BOSC, etc. Here, ξ- π was proposed to decompose the neural spectra by embedding the nonparametric spectra estimation with penalized Whittle likelihood and the shape language modeling into the expectation maximization framework. ξ- π was validated on the synthesized spectra with loss statistics and on the sleep EEG and the large sample iEEG with evaluation metrics and neurophysiological evidence. Compared to FOOOF, both the simulation presenting shape irregularities and the batch simulation with multiple isolated peaks indicated that ξ- π improved the fit of AC and PCs with less loss and higher F1-score in recognizing the centering frequencies and the number of peaks; the sleep EEG revealed that ξ- π produced more distinguishable AC exponents and improved the sleep state classification accuracy; the iEEG showed that ξ- π approached the clinical findings in peak discovery. Overall, ξ- π offered good performance in the spectra decomposition, which allows flexible parameterization using descriptive statistics or kernel functions. ξ- π is a seminal tool for brain signal decoding in fields such as cognitive neuroscience, brain-computer interface, neurofeedback, and brain diseases.


Assuntos
Encéfalo , Eletroencefalografia , Processamento de Sinais Assistido por Computador , Humanos , Eletroencefalografia/métodos , Encéfalo/fisiologia , Algoritmos , Estatísticas não Paramétricas , Sono/fisiologia
9.
Rapid Commun Mass Spectrom ; 38(6): e9707, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38356093

RESUMO

RATIONALE: A novel laser ablation-isotope ratio mass spectrometry (LA-IRMS) method for in situ analysis of sulfur isotopes in sulfides has been developed. Instead of the in situ reaction applied by the traditional laser microprobe, the analyte gas preparation in this method is separated temporally and spatially from the LA, resulting in improved precision and accuracy. METHODS: Our LA-IRMS system combines an ultraviolet LA system, an elemental analyzer (EA), a custom-built cryogenic concentration system, a continuous-flow interface, and an IRMS. The sulfide aerosol particles generated from LA were transferred by a helium carrier gas from the ablation cell into the reaction tube and were then converted into SO2 . Subsequently, SO2 was enriched in two cold traps and was finally introduced into the ion source of the IRMS through the continuous-flow interface. RESULTS: We measured three synthetic and four natural sulfide reference materials to test the performance of this method. Precisions of ±0.25‰-±0.48‰ and ±0.32‰-±0.64‰ (1SD, n = 5) for δ34 S values of synthetic and natural sulfide standards can be obtained for spot sizes ranging from 64 to 80 µm. Measured values and their recommended values showed a good linear relationship (R2 within 0.998 and 0.9995) with the slope of approaching unity (within 1.0509 and 1.1313). CONCLUSIONS: Data from the measurement of reference materials showed that the precision and accuracy of our method were satisfactory. This method is a powerful tool for in situ sulfur isotope measurement of sulfides and can be further applied to in situ carbon and oxygen isotope analyses.

10.
Small ; : e2310194, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38279612

RESUMO

Spinal cord injury (SCI) often leads to cell death, vascular disruption, axonal signal interruption, and permanent functional damage. Currently, there are no clearly effective therapeutic options available for SCI. Considering the inhospitable SCI milieu typified by ischemia, hypoxia, and restricted neural regeneration, a novel injectable hydrogel system containing conductive black phosphorus (BP) nanosheets within a lipoic acid-modified chitosan hydrogel matrix (LAMC) is explored. The incorporation of tannic acid (TA)-modified BP nanosheets (BP@TA) into the LAMC hydrogel matrix significantly improved its conductivity. Further, by embedding a bicyclodextrin-conjugated tazarotene drug, the hydrogel showcased amplified angiogenic potential in vitro. In a rat model of complete SCI, implantation of LAMC/BP@TA hydrogel markedly improved the recovery of motor function. Immunofluorescence evaluations confirmed that the composite hydrogel facilitated endogenous angiogenesis and neurogenesis at the injury site. Collectively, this work elucidates an innovative drug-incorporated hydrogel system enriched with BP, underscoring its potential to foster vascular and neural regeneration.

11.
Neural Netw ; 168: 508-517, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37832318

RESUMO

Recent multi-domain processing methods have demonstrated promising performance for monaural speech enhancement tasks. However, few of them explain why they behave better over single-domain approaches. As an attempt to fill this gap, this paper presents a complementary single-channel speech enhancement network (CompNet) that demonstrates promising denoising capabilities and provides a unique perspective to understand the improvements introduced by multi-domain processing. Specifically, the noisy speech is initially enhanced through a time-domain network. However, despite the waveform can be feasibly recovered, the distribution of the time-frequency bins may still be partly different from the target spectrum when we reconsider the problem in the frequency domain. To solve this problem, we design a dedicated dual-path network as a post-processing module to independently filter the magnitude and refine the phase. This further drives the estimated spectrum to closely approximate the target spectrum in the time-frequency domain. We conduct extensive experiments with the WSJ0-SI84 and VoiceBank + Demand datasets. Objective test results show that the performance of the proposed system is highly competitive with existing systems.


Assuntos
Algoritmos , Fala , Ruído , Razão Sinal-Ruído
12.
J Nanobiotechnology ; 21(1): 284, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37605203

RESUMO

Osteoarthritis (OA) is a common degenerative joint disease urgently needing effective treatments. Bone marrow mesenchymal stromal cell-derived exosomes (Exo) are considered good drug carriers whereas they have limitations such as fast clearance and low retention. This study aimed to overcome the limitations of Exo in drug delivery using multiple strategies. Novel photocrosslinking spherical gelatin methacryloyl hydrogel (GelMA)-encapsulated cartilage affinity WYRGRL (W) peptide-modified engineered Exo were developed for OA treatment and the performance of the engineered Exo (W-Exo@GelMA) loaded with a small inhibitor LRRK2-IN-1 (W-Exo-L@GelMA) was investigated in vitro and in vivo. The W-Exo-L@GelMA showed an effective targeting effect on chondrocytes and a pronounced action on suppressing catabolism and promoting anabolism in vitro. Moreover, W-Exo-L@GelMA remarkably inhibited OA-related inflammation and immune gene expression, rescuing the IL-1ß-induced transcriptomic responses. With enhanced retention in the joint, W-Exo-L@GelMA demonstrated superior anti-OA activity and cartilage repair ability in the OA murine model. The therapeutic effect was validated in the cultured human OA cartilage. In conclusion, photocrosslinking spherical hydrogel-encapsulated targeting peptide-modified engineered Exo exhibit notable potential in OA therapy. Engineering Exo by a series of strategies enhanced the targeting ability and retention and cartilage-targeting and Exo-mediated drug delivery may offer a novel strategy for OA treatment.Clinical trial registration: Not applciable.


Assuntos
Exossomos , Osteoartrite , Humanos , Animais , Camundongos , Hidrogéis , Sistemas de Liberação de Medicamentos , Peptídeos , Osteoartrite/tratamento farmacológico
13.
Eur J Pharmacol ; 954: 175876, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37391008

RESUMO

BACKGROUND AND AIMS: M1 polarization of macrophages in the intestine is an important maintenance factor of the inflammatory response in Crohn's disease (CD). Eriocalyxin B (EriB) is a natural medicine that antagonizes inflammation. Our study aimed to determine the effects of EriB on CD-like colitis in mice, as well as the possible mechanism. METHODS: 2,4,6-trinitrobenzene sulfonic acid (TNBS) mice and Il-10-/- mice were used as CD animal models, and the therapeutic effect of EriB on CD-like colitis in mice was addressed by the disease activity index (DAI) score, weight change, histological analysis and flow cytometry assay. To assess the direct role of EriB in regulating macrophage polarization, bone marrow-derived macrophages (BMDMs) were induced to M1 or M2 polarization separately. Molecular docking simulations and blocking experiments were performed to explore the potential mechanisms by which EriB regulates the macrophage polarization. RESULTS: EriB treatment reduced body weight loss, DAI score and histological score, demonstrating the improvement of colitis symptoms in mice. In vivo and in vitro experiments both showed that EriB decreased the M1 polarization of macrophages, and suppressed the release of proinflammatory cytokines (IL-1ß, TNF-α and IL-6) in mouse colons and BMDMs. The activation of Janus kinase 2/signal transducer and activator of transcription 1 (JAK2/STAT1) signals could be inhibited by EriB, which may be related to the regulation of EriB on M1 polarization. CONCLUSIONS: EriB inhibits the M1 polarization of macrophages by attenuating the JAK2/STAT1 pathway, which partially explains the potential mechanism by which EriB ameliorates colitis in mice, and provides a new regimen for the clinical treatment of CD.


Assuntos
Colite , Doença de Crohn , Animais , Camundongos , Doença de Crohn/tratamento farmacológico , Janus Quinase 2/metabolismo , Simulação de Acoplamento Molecular , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Macrófagos
14.
Bioact Mater ; 28: 348-357, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37334067

RESUMO

Magnesium phosphate bone cement has become a widely used orthopedic implant due to the advantages of fast-setting and high early strength. However, developing magnesium phosphate cement possessing applicable injectability, high strength, and biocompatibility simultaneously remains a significant challenge. Herein, we propose a strategy to develop high-performance bone cement and establish a trimagnesium phosphate cement (TMPC) system. The TMPC exhibits high early strength, low curing temperature, neutral pH, and excellent injectability, overcoming the critical limitations of recently studied magnesium phosphate cement. By monitoring the hydration pH value and electroconductivity, we demonstrate that the magnesium-to-phosphate ratio could manipulate the components of hydration products and their transformation by adjusting the pH of the system, which will influence the hydration speed. Further, the ratio could regulate the hydration network and the properties of TMPC. Moreover, in vitro studies show that TMPC has outstanding biocompatibility and bone-filling capacity. The facile preparation properties and these advantages of TMPC render it a potential clinical alternative to polymethylmethacrylate and calcium phosphate bone cement. This study will contribute to the rational design of high-performance bone cement.

15.
J Mater Chem B ; 11(20): 4485-4497, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37159227

RESUMO

The complex structure of the root canal system and microbial resistance increase the difficulty of endodontic treatment and the development of root canal sealers with good antibacterial and physicochemical properties is the key to treat refractory root canal infection. In the present study, a novel premixed root canal sealer containing trimagnesium phosphate (TMP), potassium dihydrogen phosphate (KH2PO4), magnesium oxide (MgO), zirconium oxide (ZrO2), and a bioactive oil phase was developed, and the physicochemical properties, radiopacity, antibacterial activity in vitro, anti-biofilm ability and cytotoxicity were investigated. MgO significantly improved the anti-biofilm ability and ZrO2 enhanced the radiopacity of the premixed sealer, and they had an obvious adverse effect on other properties. In addition, this sealer has advantages such as easy-to-use design, storabality, good sealing ability and biocompatibility. Therefore, this sealer has high potential for use in treating root canal infection.


Assuntos
Materiais Restauradores do Canal Radicular , Materiais Restauradores do Canal Radicular/farmacologia , Óxido de Magnésio , Cavidade Pulpar , Fosfatos/química , Antibacterianos/farmacologia , Antibacterianos/química
16.
Front Bioeng Biotechnol ; 11: 1142264, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008035

RESUMO

The high concentration of antibacterial metal ions may exhibit unavoidable toxicity to cells and normal tissues. The application of antibacterial metal ions to activate the immune response and induce macrophages to attack and phagocytose bacteria is a new antimicrobial strategy. Herein, 3D-printed Ti-6Al-4V implants modified by copper, and strontium ions combined with natural polymers were designed to treat implant-related infections and osseointegration disorders. The polymer-modified scaffolds rapidly released a large amount of copper and strontium ions. During the release process, copper ions were employed to promote the polarization of M1 macrophages, thus inducing a proinflammatory immune response to inhibit infection and achieve the immune antibacterial activity. Meanwhile, copper and strontium ions promoted the secretion of bone-promoting factors by macrophages, induced osteogenesis and showed immunomodulatory osteogenesis. This study proposed immunomodulatory strategies based on the immunological characteristics of target diseases and provided ideas for the design and synthesis of new immunoregulatory biomaterials.

17.
Biotechnol Genet Eng Rev ; : 1-17, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37057740

RESUMO

The long non-coding RNA (LncRNA) X-inactive specific transcript (XIST) regulates the biological process of osteoclasts and the process of related diseases. This study was attempted to investigate the mechanism of LncRNA XIST acting in osteoclast formation and orthodontic induced inflammatory root resorption (OIIRR). The compression force (CF) -induced cell model and the orthodontic tooth movement (OTM) rat model were designed and established in this study. The expression of LncRNA XIST, miR-130b-3p, phosphatase and tensin homolog deleted on chromosome 10 (PTEN) as well as osteoclast related marker genes and inflammatory factors level were measured in this study. The interaction among LncRNA XIST, microRNA-130b-3p (miR-130b-3p) and PTEN were researched through luciferase activity and western blot assay. Pathological sections were used to analyze root resorption and osteoclast formation. The OTM rat model was successfully constructed, which was characterized by increased tooth spacing and increased root resorption pits. PTEN and LncRNA XIST was overexpressed in OTM group. Mechanism analysis showed that the overexpression of LncRNA XIST enhanced the PTEN level by sponging miR-130b-3p. The overexpression of LncRNA XIST increased the secretion of inflammatory factors and positive osteoclasts number, but inhibited the differentiation of osteoclasts by sponging miR-130b-3p and promoting the level of PTEN. This finding demonstrates that LncRNA XIST regulates osteoclast formation and aggravated OIIRR through miR-130b-3p/PTEN axis, suggesting that LncRNA XIST may be used as potential targets for OIIRR therapy.

18.
Front Plant Sci ; 14: 1123707, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37025132

RESUMO

Background: The genus Rhododendron (Ericaceae), a species-rich and widely distributed genus of woody plants, is distinguished for the beautiful and diverse flowers. Rhododendron delavayi Franch. and Rhododendron irroratum Franch., are highly attractive species widely distributed in south-west China and abundant new varieties have been selected from their genetic resources. Methods: We constructed chromosome-scale genome assemblies for Rhododendron delavayi and Rhododendron irroratum. Phylogenetic and whole-genome duplication analyses were performed to elucidate the evolutionary history of Rhododendron. Further, different types of gene duplications were identified and their contributions to gene family expansion were investigated. Finally, comprehensive characterization and evolutionary analysis of R2R3-MYB and NBS-encoding genes were conducted to explore their evolutionary patterns. Results: The phylogenetic analysis classified Rhododendron species into two sister clades, 'rhododendrons' and 'azaleas'. Whole-genome duplication (WGD) analysis unveiled only one WGD event that occurred in Rhododendron after the ancestral γ triplication. Gene duplication and gene family expansion analyses suggested that the younger tandem and proximal duplications contributed greatly to the expansion of gene families involved in secondary metabolite biosynthesis and stress response. The candidate R2R3-MYB genes likely regulating anthocyanin biosynthesis and stress tolerance in Rhododendron will facilitate the breeding for ornamental use. NBS-encoding genes had undergone significant expansion and experienced species-specific gain and loss events in Rhododendron plants. Conclusions: The reference genomes presented here will provide important genetic resources for molecular breeding and genetic improvement of plants in this economically important Rhododendron genus.

19.
Biomed Opt Express ; 14(3): 1119-1136, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36950226

RESUMO

Remote photoplethysmogram (rPPG) is a low-cost method to extract blood volume pulse (BVP). Some crucial vital signs, such as heart rate (HR) and respiratory rate (RR) etc. can be achieved from BVP for clinical medicine and healthcare application. As compared to the conventional PPG methods, rPPG is more promising because of its non-contacted measurement. However, both BVP detection methods, especially rPPG, are susceptible to motion and illumination artifacts, which lead to inaccurate estimation of vital signs. Signal quality assessment (SQA) is a method to measure the quality of BVP signals and ensure the credibility of estimated physiological parameters. But the existing SQA methods are not suitable for real-time processing. In this paper, we proposed an end-to-end BVP signal quality evaluation method based on a long short-term memory network (LSTM-SQA). Two LSTM-SQA models were trained using the BVP signals obtained with PPG and rPPG techniques so that the quality of BVP signals derived from these two methods can be evaluated, respectively. As there is no publicly available rPPG dataset with quality annotations, we designed a training sample generation method with blind source separation, by which two kinds of training datasets respective to PPG and rPPG were built. Each dataset consists of 38400 high and low-quality BVP segments. The achieved models were verified on three public datasets (IIP-HCI dataset, UBFC-Phys dataset, and LGI-PPGI dataset). The experimental results show that the proposed LSTM-SQA models can effectively predict the quality of the BVP signal in real-time.

20.
Plants (Basel) ; 12(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36903929

RESUMO

Long non-coding RNAs (lncRNAs) are crucial players regulating many biological processes in plants. However, limited knowledge is available regarding their roles in kiwifruit ripening and softening. In this study, using lncRNA-seq technology, 591 differentially expressed (DE) lncRNAs (DELs) and 3107 DE genes (DEGs) were identified from kiwifruit stored at 4 °C for 1, 2, and 3 weeks in comparison with non-treated control fruits. Of note, 645 DEGs were predicted to be targets of DELs (DEGTLs), including some DE protein-coding genes (such as ß-amylase and pectinesterase). DEGTL-based GO enrichment analysis revealed that these genes were significantly enriched in cell wall modification and pectinesterase activity in 1 W vs. CK and 3 W vs. CK, which might be closely related to the fruit softening during low-temperature storage. Moreover, KEGG enrichment analysis revealed that DEGTLs were significantly associated with starch and sucrose metabolism. Our study revealed that lncRNAs play critical regulatory roles in kiwifruit ripening and softening under low-temperature storage, mainly by mediating the expression of starch and sucrose metabolism and cell wall modification related genes.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA