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1.
PLoS Pathog ; 19(10): e1011662, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37788227

RESUMEN

Coxsackievirus A10 (CVA10) has recently emerged as one of the major causative agents of hand, foot, and mouth disease. CVA10 may also cause a variety of complications. No approved vaccine or drug is currently available for CVA10. The residues of CVA10 critical for viral attachment, infectivity and in vivo pathogenicity have not been identified by experiment. Here, we report the identification of CVA10 residues important for binding to cellular receptor KREMEN1. We identified VP2 N142 as a key receptor-binding residue by screening of CVA10 mutants resistant to neutralization by soluble KREMEN1 protein. The receptor-binding residue N142 is exposed on the canyon rim but highly conserved in all naturally occurring CVA10 strains, which provides a counterexample to the canyon hypothesis. Residue N142 when mutated drastically reduced receptor-binding activity, resulting in decreased viral attachment and infection in cell culture. More importantly, residue N142 when mutated reduced viral replication in limb muscle and spinal cord of infected mice, leading to lower mortality and less severe clinical symptoms. Additionally, residue N142 when mutated could decrease viral binding affinity to anti-CVA10 polyclonal antibodies and a neutralizing monoclonal antibody and render CVA10 resistant to neutralization by the anti-CVA10 antibodies. Overall, our study highlights the essential role of VP2 residue N142 of CVA10 in the interactions with KREMEN1 receptor and neutralizing antibodies and viral virulence in mice, facilitating the understanding of the molecular mechanisms of CVA10 infection and immunity. Our study also provides important information for rational development of antibody-based treatment and vaccines against CVA10 infection.


Asunto(s)
Anticuerpos Neutralizantes , Enterovirus , Animales , Ratones , Enterovirus/genética , Virulencia , Anticuerpos Antivirales
2.
J Cell Physiol ; 239(3): e31080, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37450667

RESUMEN

SUMOylation plays an essential role in diverse physiological and pathological processes. Identification of wild-type SUMO1-modification sites by mass spectrometry is still challenging. In this study, we produced a monoclonal SUMO1C-K antibody recognizing SUMOylated peptides and proposed an efficient streamline for identification of SUMOylation sites. We identified 471 SUMOylation sites in 325 proteins from five raw data. These identified sites exhibit a high positive rate when evaluated by mutation-verified SUMOylation sites. We identified many SUMOylated proteins involved in mitochondrial metabolism and non-membrane-bounded organelles formation. We proposed a SUMOylation motif, ΨKXD/EP, where proline is required for efficient SUMOylation. We further revealed SUMOylation of TFII-I was stimulated by growth signals and was required for nucleus-localization of p-ERK1/2. Mutation of SUMOylation sites of TFII-I suppressed tumor cell growth in vitro and in vivo. Taken together, we provided a strategy for personalized identification of wild-type SUMO1-modification sites and revealed the physiological significance of TFII-I SUMOylation in this study.


Asunto(s)
Neoplasias , Proteína SUMO-1 , Sumoilación , Factores de Transcripción TFII , Humanos , Anticuerpos Monoclonales , Espectrometría de Masas , Neoplasias/genética , Neoplasias/patología , Péptidos/metabolismo , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo , Sumoilación/genética , Factores de Transcripción TFII/metabolismo
3.
Biochem Biophys Res Commun ; 690: 149241, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38000297

RESUMEN

The deleterious effects of diabetes mellitus on wound healing have become a major public health concern worldwide. Given the complex microenvironment of diabetic wounds and the high prevalence of diabetes, the design and development of novel wound dressing materials with versatile capabilities is urgent. Extracellular vesicles (EVs) derived from human umbilical cord blood have demonstrated the potential to counter inflammation and accelerate wound healing. Herein, we explored the efficacy of incorporating human umbilical cord blood-derived exosomes (UCB-Exos) into an ABA-type amphiphilic hydrogel, which possesses the attributes of exosome (Exo) encapsulation, temperature-triggered reversible sol-gel conversion, and Exo-regulated release, for enhancing the stability and retention of Exos. We sought to examine the feasibility of this strategy in augmenting the therapeutic efficacy of UCB-Exos for the healing of diabetes-related wounds. The injectable hydrogel was conveniently applied directly onto the wound surface and the enclosed Exo significantly facilitated the healing process, resulting in faster wound closure, enhanced collagen deposition, accelerated re-epithelialization, and enhanced neo-vascularization within two weeks compared with the hydrogel-only treatment group. In summary, some hydrogels hold great promise for promoting wound healing in diabetics and represent a novel therapeutic option for diabetes-related ulcers.


Asunto(s)
Diabetes Mellitus Experimental , Exosomas , Animales , Humanos , Hidrogeles/farmacología , Sangre Fetal , Cicatrización de Heridas , Diabetes Mellitus Experimental/tratamiento farmacológico
4.
Opt Express ; 32(6): 9699-9709, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571198

RESUMEN

In order to enhance the performance of a continuous-wave photocathode electron gun at Peking University, and to achieve electron beams with higher current and brightness, a multifunctional drive laser system named PULSE (Peking University drive Laser System for high-brightness Electron source) has been developed. This innovative system is capable of delivering an average output power of 120 W infrared laser pulse at 81.25 MHz, as well as approximately 13.8 W of green power with reliable stability. The utilization of two stages of photonic crystal fibers plays a crucial role in achieving this output. Additionally, the incorporation of two acousto-optic modulators enables the selection of macro-pulses with varying repetition frequencies and duty cycles, which is essential for effective electron beam diagnosis. Furthermore, the system employs a series of birefringent crystals for temporal pulse shaping, allowing for stacking Gaussian pulses into multiple types of distribution. Overall, the optical schematic and operating performance of PULSE are detailed in this paper.

5.
Fish Shellfish Immunol ; 148: 109525, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38537926

RESUMEN

Serine protease inhibitors Kazal type (SPINKs) function in physiological and immunological processes across multicellular organisms. In the present study, we identified a SPINK gene, designated as CqSPINK, in the red claw crayfish Cherax quadricarinatus, which is the ortholog of human SPINK5. The deduced CqSPINK contains two Kazal domains consisting of 45 amino acid residues with a typical signature motif C-X3-C-X5-PVCG-X5-Y-X3-C-X6-C-X12-14-C. Each Kazal domain contains six conserved cysteine residues forming three pairs of disulfide bonds, segmenting the structure into three rings. Phylogenetic analysis revealed CqSPINK as a homolog of human SPINK5. CqSPINK expression was detected exclusively in hepatopancreas and epithelium, with rapid up-regulation in hepatopancreas upon Vibrio parahaemolyticus E1 challenge. Recombinant CqSPINK protein (rCqSPINK) was heterologously expressed in Escherichia coli and purified for further study. Proteinase inhibition assays demonstrated that rCqSPINK could potently inhibit proteinase K and subtilisin A, weakly inhibit α-chymotrypsin and elastase, but extremely weak inhibit trypsin. Furthermore, CqSPINK inhibited bacterial secretory proteinase activity from Bacillus subtilis, E. coli, and Staphylococcus aureus, and inhibited B. subtilis growth. These findings suggest CqSPINK's involvement in antibacterial immunity through direct inhibition of bacterial proteases, contributing to resistance against pathogen invasion.


Asunto(s)
Astacoidea , Inhibidores de Serina Proteinasa , Humanos , Animales , Inhibidores de Serina Proteinasa/genética , Inhibidores de Serina Proteinasa/química , Filogenia , Escherichia coli , Proteínas Recombinantes/genética , Bacterias/metabolismo
6.
Mol Biol Rep ; 51(1): 204, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38270817

RESUMEN

BACKGROUND: Acute liver damage is a type of liver disease that has a significant global occurrence and a lack of successful treatment and prevention approaches. Sodium humate (HNa), a natural organic substance, has extensive applications in traditional Chinese medicine due to its antibacterial, anti-diarrheal, and anti-inflammatory characteristics. The purpose of this research was to examine the mitigating impacts of HNa on liver damage induced by lipopolysaccharide (LPS) in mice. METHODS AND RESULTS: A total of 30 female mice were randomly assigned into Con, Mod, L-HNa, M-HNa, and H-HNa groups. Mice in the Con and Mod groups were gavaged with PBS, whereas L-HNa, M-HNa, and H-HNa groups mice were gavaged with 0.1%, 0.3%, and 0.5% HNa, daily. On day 21, Mod, L-HNa, M-HNa, and H-HNa groups mice were challenged with LPS (10 mg/kg). We discovered that pretreatment with HNa improved liver pathological damage and inflammation by inhibiting the toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) signaling pathway, enhancing the polarization of liver M2 macrophages, and reducing the levels of inflammatory cytokines. Our further study found that pretreatment with HNa enhanced the liver ability to combat oxidative stress and reduced hepatocyte apoptosis by activating the nuclear factor erythroid-2-related factor 2 (NRF2)/heme oxygenase-1 (HO-1) signaling pathway and enhancing the activities of antioxidant enzymes. CONCLUSIONS: In conclusion, HNa could alleviate LPS-induced liver damage through inhibiting TLR4/NF-κB and activating NRF2/HO-1 signaling pathways. This study is the first to discover the therapeutic effects of HNa on liver damage induced by LPS.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , FN-kappa B , Femenino , Animales , Ratones , Lipopolisacáridos , Receptor Toll-Like 4 , Factor 2 Relacionado con NF-E2 , Hemo-Oxigenasa 1 , Transducción de Señal
7.
Biol Cell ; 115(12): e202300057, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37851997

RESUMEN

BACKGROUND INFORMATION: Persistent myelin debris can inhibit axonal regeneration, thereby hindering remyelination. Effective removal of myelin debris is essential to eliminate the interference of myelin debris in oligodendrocyte progenitor cell (OPC) activation, recruitment to demyelinating sites and/or differentiation into mature oligodendrocytes (OLs). In addition to microglia, it has been reported that astrocytic phagocytosis of myelin debris is a feature of early demyelination. RESULTS: In the present study, astrocytes effectively phagocytized myelin debris in vitro and in vivo. On the 5th day after injecting myelin debris into the brain, astrocytes were enriched in the area injected with myelin debris compared with microglia, and their ability to engulf myelin debris was stronger than that of microglia. When exposed to myelin debris, astrocytes phagocytizing myelin debris triggered self-apoptosis, accompanied by the activation of NF-κB, down-regulation of Nrf2, and the increase of ciliary neurotrophic factor (CNTF) and basic fibroblast growth factor (bFGF). However, the activation of astrocytic NF-κB did not influence the inflammatory cytokines IL-1ß, IL-6, and TNF-α, and the anti-inflammatory factor IL-10. The proliferation of astrocytes and mobilization of OPCs in the subventricular zone were elevated on the 5th day after intracerebral injection of myelin debris. CONCLUSIONS: The results suggested that myelin phagocytosis of astrocytes should help improve the microenvironment and promote myelin regeneration by increasing CNTF and bFGF within the central nervous system. SIGNIFICANCE: However, the molecular interaction of astrocytes acting as phagocytes remains to be further explored. Therefore, an improvement of astrocytes to phagocytize myelin debris may be a promising treatment measure to prevent demyelination and promote remyelination in MS and other diseases with prominent myelin injury.


Asunto(s)
Enfermedades Desmielinizantes , Vaina de Mielina , Humanos , Vaina de Mielina/metabolismo , Astrocitos/metabolismo , Enfermedades Desmielinizantes/metabolismo , Factor Neurotrófico Ciliar/metabolismo , FN-kappa B/metabolismo , Fagocitosis , Oligodendroglía/metabolismo
8.
Artículo en Inglés | MEDLINE | ID: mdl-39066853

RESUMEN

OPINION STATEMENT: Anthracycline (ANT)-induced cardiotoxicity (AIC) is a particularly prominent form of cancer therapy-related cardiovascular toxicity leading to the limitations of ANTs in clinical practice. Even though AIC has drawn particular attention, the best way to treat it is remaining unclear. Updates to AIC therapy have been made possible by recent developments in research on the underlying processes of AIC. We review the current molecular pathways leading to AIC: 1) oxidative stress (OS) including enzymatic-induced and other mechanisms; 2) topoisomerase; 3) inflammatory response; 4) cardiac progenitor cell damage; 5) epigenetic changes; 6) renin-angiotensin-aldosterone system (RAAS) dysregulation. And we systematically discuss current prevention and treatment strategies and novel pathogenesis-based therapies for AIC: 1) dose reduction and change; 2) altering drug delivery methods; 3) antioxidants, dexrezosen, statina, RAAS inhibitors, and hypoglycemic drugs; 4) miRNA, natural phytochemicals, mesenchymal stem cells, and cardiac progenitor cells. We also offer a fresh perspective on the management of AIC by outlining the current dilemmas and challenges associated with its prevention and treatment.

9.
Bioorg Chem ; 147: 107375, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38636437

RESUMEN

The dried fruit of Amomum villosum is an important spice and medicinal plant that has received great attention in recent years due to its high content of bioactive components and its potential for food additives and drug development. However, the stems and leaves of A. villosum are usually disposed of as waste. Based on the study of the fruits of A. villosum, we also systematically studied its stems and leaves. Fourteen aromatic compounds (1-14) were isolated and identified from A. villosum, including five new compounds (1-5) and nine known compounds (6-14). Among them, compounds 2-5, 8-10, 12-13 were obtained from the fruits of A. villosum, and compounds 1, 6-7,11, 14 were isolated from the stems and leaves of A. villosum. Based on chemical evidence and spectral data analysis (UV, ECD, Optical rotation data, 1D and 2D-NMR, and HR-ESI-MS), the structures of new compounds were elucidated. Furthermore, all compounds were tested for their effects on the survival rate of BV-2 cells in the presence of hydrogen peroxide. Among them, compound 5 showed antioxidant effects. Through network pharmacology screening and the cell thermal shift assay (CETSA), the Phosphoglycerate Mutase 5 (PGAM5) protein was identified as the antioxidant target of compound 5. Molecular docking results showed that compound 5 maintains binding to PGAM5 by forming hydrogen bond interactions with Lys93 and Agr214. In summary, A. villosum had potential medicinal and food values due to the diverse bioactive components.


Asunto(s)
Amomum , Antioxidantes , Simulación del Acoplamiento Molecular , Amomum/química , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Estructura Molecular , Relación Estructura-Actividad , Relación Dosis-Respuesta a Droga , Supervivencia Celular/efectos de los fármacos , Humanos , Animales , Hojas de la Planta/química
10.
Bioorg Chem ; 145: 107190, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38377816

RESUMEN

The fruits of Amomum villosum are often considered a medicinal and food homologous material and have been found to have therapeutic effects in chronic enteritis, gastroenteritis, and duodenal ulcer. The aim of this study is to discover the anti-inflammatory active ingredients from dried ripe fruits of A. villosum and to elucidate the molecular mechanisms. We verified that the inhibitory activity of the ethyl acetate extract was superior to Dexamethasone (Dex), so we ultimately chose to study the ethyl acetate extract from the fruits of A. villosum. A total of 33 compounds were isolated from its ethyl acetate extract, including nine known diterpenoids (compounds 1-9), twelve known sesquiterpenoids (compounds 10-21), ten known phenolics (compounds 22, 23, 25-29, 31-33) and two new phenolics (24 and 30). On the basis of chemical evidences and spectral data analysis (UV, ECD, Optical rotation data, 1D and 2D-NMR, HR-ESI-MS, NMR chemical shift calculations), the structures of new compounds were elucidated. Among these compounds, isocoronarin D (5) was found to have good anti-inflammatory activity. Further research has found that isocoronarin D can down-regulate the protein levels of COX2 and NOS2, activate Nrf2/Keap1 and suppress NF-κB signaling pathway in LPS-induced RAW264.7 cells. In addition, isocoronarin D inhibited inflammasome assembly during inflammasome activation by hampering the binding of NLRP3 and ASC. Further evidence revealed that isocoronarin D suppressed the assembly of the NLRP3 inflammasome via blocking the formation of ASC specks. From these results, isocoronarin D may be the important bioactive compound of A. villosum and exhibits anti-inflammatory effects by regulating the NF-κB/Nrf2/NLRP3 axis in macrophages.


Asunto(s)
Acetatos , Amomum , Diterpenos , Imidazoles , Sulfonamidas , Tiofenos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Inflamasomas/metabolismo , Amomum/química , Terpenos , FN-kappa B/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch , Frutas/química , Factor 2 Relacionado con NF-E2/metabolismo , Antiinflamatorios/farmacología , Lipopolisacáridos/farmacología
11.
Bioorg Chem ; 148: 107482, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38795582

RESUMEN

Toad venom, a traditional Chinese medicine, exhibits remarkable medicinal properties of significant therapeutic value. The peptides present within toad venom possess a wide range of biological functions, yet the neuropeptide B (NPB) and it modification requires further exploration to comprehensively understand its mechanisms of action and potential applications. In this study, a fusion peptide, ANTP-BgNPB, was designed to possess better analgesic properties through the transdermal modification of BgNPB. After optimizing the conditions, the expression of ANTP-BgNPB was successfully induced. The molecular dynamics simulations suggested that the modified protein exhibited improved stability and receptor binding affinity compared to its unmodified form. The analysis of the active site of ANTP-BgNPB and the verification of mutants revealed that GLN3, SER38, and ARG42 were crucial for the protein's recognition and binding with G protein-coupled receptor 7 (GPR7). Moreover, experiments conducted on mice using the hot plate and acetic acid twist body models demonstrated that ANTP-BgNPB was effective in transdermal analgesia. These findings represent significant progress in the development of transdermal delivery medications and could have a significant impact on pain management.


Asunto(s)
Analgésicos , Diseño de Fármacos , Animales , Analgésicos/química , Analgésicos/farmacología , Ratones , Péptidos/química , Péptidos/farmacología , Administración Cutánea , Masculino , Relación Estructura-Actividad , Simulación de Dinámica Molecular , Estructura Molecular , Relación Dosis-Respuesta a Droga , Dolor/tratamiento farmacológico , Humanos
12.
Mol Ther ; 31(9): 2575-2590, 2023 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-37408308

RESUMEN

Tertiary lymphoid structures (TLSs) in tumor tissues facilitate immune cell trafficking and cytotoxicity, which benefits survival and favorable responses in immune therapy. Here, we observed a high correlation of tumor necrosis factor superfamily member 14 (LIGHT) expression with TLS signature genes, which are all markers for immune cell accumulation and better prognosis, through retrieving RNA sequencing (RNA-seq) data from patients with cancer, suggesting the potential of LIGHT in reconstituting a high immune-infiltrated tumor microenvironment. Accordingly, LIGHT co-expressed chimeric antigen receptor T (LIGHT CAR-T) cells not only showed enhanced cytotoxicity and cytokine production but also improved CCL19 and CCL21 expression by surrounding cells. And the supernatant of LIGHT CAR-T cells promoted T cell migration in a paracrine manner. Furthermore, LIGHT CAR-T cells showed superior anti-tumor efficacy and improved infiltration in comparison with conventional CAR-T cells in immunodeficient NSG mice. Accordingly, murine LIGHT-OT-1 T cells normalized tumor blood vessels and enforced intratumoral lymphoid structures in C57BL/6 syngeneic tumor mouse models, implying the potential of LIGHT CAR-T in clinical application. Taken together, our data revealed a straightforward strategy to optimize trafficking and cytotoxicity of CAR-T cells by redirecting TLSs through LIGHT expression, which has great potential to expand and optimize the application of CAR-T therapy in solid tumors.


Asunto(s)
Receptores Quiméricos de Antígenos , Miembro 14 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral , Animales , Ratones , Línea Celular Tumoral , Inmunoterapia Adoptiva , Ratones Endogámicos C57BL , Receptores Quiméricos de Antígenos/metabolismo , Linfocitos T , Microambiente Tumoral/genética
13.
Mol Cell Proteomics ; 21(2): 100187, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34922009

RESUMEN

Drug resistance is a critical obstacle to effective treatment in patients with chronic myeloid leukemia. To understand the underlying resistance mechanisms in response to imatinib mesylate (IMA) and adriamycin (ADR), the parental K562 cells were treated with low doses of IMA or ADR for 2 months to generate derivative cells with mild, intermediate, and severe resistance to the drugs as defined by their increasing resistance index. PulseDIA-based (DIA [data-independent acquisition]) quantitative proteomics was then employed to reveal the proteome changes in these resistant cells. In total, 7082 proteins from 98,232 peptides were identified and quantified from the dataset using four DIA software tools including OpenSWATH, Spectronaut, DIA-NN, and EncyclopeDIA. Sirtuin signaling pathway was found to be significantly enriched in both ADR-resistant and IMA-resistant K562 cells. In particular, isocitrate dehydrogenase (NADP(+)) 2 was identified as a potential drug target correlated with the drug resistance phenotype, and its inhibition by the antagonist AGI-6780 reversed the acquired resistance in K562 cells to either ADR or IMA. Together, our study has implicated isocitrate dehydrogenase (NADP(+)) 2 as a potential target that can be therapeutically leveraged to alleviate the drug resistance in K562 cells when treated with IMA and ADR.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva , Proteómica , Doxorrubicina/farmacología , Resistencia a Antineoplásicos , Humanos , Mesilato de Imatinib/farmacología , Mesilato de Imatinib/uso terapéutico , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo
14.
Mikrochim Acta ; 191(5): 267, 2024 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-38627300

RESUMEN

A ternary hierarchical hybrid Ni@CoxSy/poly(3,4-ethylenedioxythiophene)-reduced graphene oxide (Ni@CoxSy/PEDOT-rGO) is rationally designed and in situ facilely synthesized as electrocatalyst to construct a binder-free sensing platform for non-enzymatic glucose monitoring through traditional electrodeposition procedure. The as-prepared Ni@CoxSy/PEDOT-rGO presents unique hierarchical structure and multiple valence states as well as strong and robust adhesion between Ni@CoxSy/PEDOT-rGO and GCE. Profiting from the aforementioned merits, the sensing platform constructed under optimal conditions achieved a wide detection range (0.2 µM ~ 2.0 mM) with high sensitivity (1546.32 µA cm-2 mM-1), a rapid response time (5 s), an ultralow detection limit (0.094 µM), superior anti-interference performance, excellent reproducibility and considerable stability. Furthermore, the sensor demonstrates an acceptable accuracy and appreciable recoveries ranging from 90.0 to 102.0% with less than 3.98% RSD in human blood serum samples, indicating the prospect of the sensor for the real samples analysis. It will provide a strategy to rationally design and fabricate ternary hierarchical hybrid as nanozyme for glucose assay.


Asunto(s)
Glucemia , Compuestos Bicíclicos Heterocíclicos con Puentes , Cobalto , Grafito , Níquel , Polímeros , Humanos , Níquel/química , Glucemia/análisis , Reproducibilidad de los Resultados , Automonitorización de la Glucosa Sanguínea , Glucosa/análisis
15.
Sensors (Basel) ; 24(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38931766

RESUMEN

Currently, complex scene classification strategies are limited to high-definition image scene sets, and low-quality scene sets are overlooked. Although a few studies have focused on artificially noisy images or specific image sets, none have involved actual low-resolution scene images. Therefore, designing classification models around practicality is of paramount importance. To solve the above problems, this paper proposes a two-stage classification optimization algorithm model based on MPSO, thus achieving high-precision classification of low-quality scene images. Firstly, to verify the rationality of the proposed model, three groups of internationally recognized scene datasets were used to conduct comparative experiments with the proposed model and 21 existing methods. It was found that the proposed model performs better, especially in the 15-scene dataset, with 1.54% higher accuracy than the best existing method ResNet-ELM. Secondly, to prove the necessity of the pre-reconstruction stage of the proposed model, the same classification architecture was used to conduct comparative experiments between the proposed reconstruction method and six existing preprocessing methods on the seven self-built low-quality news scene frames. The results show that the proposed model has a higher improvement rate for outdoor scenes. Finally, to test the application potential of the proposed model in outdoor environments, an adaptive test experiment was conducted on the two self-built scene sets affected by lighting and weather. The results indicate that the proposed model is suitable for weather-affected scene classification, with an average accuracy improvement of 1.42%.

16.
J Environ Manage ; 350: 119697, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38035504

RESUMEN

Lakes serve as vital reservoirs of dissolved organic matter (DOM) and play pivotal roles in biogeochemical carbon cycles. However, the sources and compositions of DOM in freshwater lakes and their potential effects on lake sediment carbon pools remain unclear. In this study, seven inflowing rivers in the Lake Taihu basin were selected to explore the potential effects of multi-source DOM inputs on the stability of the lake sediment carbon pool. The results showed the high concentrations of dissolved organic carbon in the Lake Taihu basin, accompanied by a high complexity level. Lignins constituted the majority of DOM compounds, surpassing 40% of the total, while the organic carbon content was predominantly composed of humic acids (1.02-3.01 g kg-1). The high amounts of lignin oxidative cleavage led to CHO being the main molecular structure in the DOM of the seven rivers. The carbon constituents within the sediment carbon reservoir exhibited a positive correlation with dissolved CH4 and CO2, with a notable emphasis on humic acid and dissolved CH4 (R2 = 0.86). The elevated concentration of DOM, coupled with its intricate composition, contributed to the increases in dissolved greenhouse gases (GHGs). Experiments showed that the mixing of multi-source DOM can accelerate the organic carbon mineralization processes. The unit carbon emission efficiency was highest in the mixed group, reaching reached 160.9 µmol∙Cg-1, which also exhibited a significantly different carbon pool. The mixed decomposition of DOM from different sources influenced the roles of the lake carbon pool as source and sink, indicating that the multi-source DOM of this lake basin was a potential driving factor for increased carbon emissions. These findings have improved our understanding of the sources and compositions of DOM in lake basins and revealed their impacts on carbon emissions, thereby providing a theoretical basis for improving assessments of lake carbon emissions.


Asunto(s)
Materia Orgánica Disuelta , Gases de Efecto Invernadero , Lagos/análisis , Lagos/química , Carbono , Ríos , Sustancias Húmicas/análisis , China
17.
Inflammopharmacology ; 32(1): 809-823, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38177566

RESUMEN

The treatment of immunomodulation in multiple sclerosis (MS) can alleviate the severity and relapses. However, it cannot improve the neurological disability of patients due to a lack of myelin protection and regeneration. Therefore, remyelinating therapies may be one of the feasible strategies that can prevent axonal degeneration and restore neurological disability. Natural product icariin (ICA) is a flavonol compound extracted from epimedium flavonoids, which has neuroprotective effects in several models of neurological diseases. Here, we attempt to explore whether ICA has the potential to treat demyelination and its possible mechanisms of action using lipopolysaccharide-treated BV2 microglia, primary microglia, bone marrow-derived macrophages, and cuprizone-induced demyelination model. The indicators of oxidative stress and inflammatory response were evaluated using commercial kits. The results showed that ICA significantly reduced the levels of oxidative intermediates nitric oxide, hydrogen peroxide, malondialdehyde, and inflammatory cytokines TNF-α, IL-1ß, and increased the levels of antioxidants superoxide dismutase, catalase, glutathione peroxidase, and anti-inflammatory cytokines IL-10 and TGF-ß in vitro cell experiments. In vivo demyelination model, ICA significantly alleviated the behavioral abnormalities and enhanced the integrated optical density/mm2 of Black Gold II and myelin basic protein myelin staining, accompanied by the inhibition of oxidative stress/inflammatory response. Immunohistochemical staining showed that ICA significantly induced the expression of nuclear factor erythroid derived 2/heme oxygenase-1 (Nrf2/HO-1) and inhibited the expression of toll-like receptor 4/ nuclear factor kappa B (TLR4/NF-κB), which are two key signaling pathways in antioxidant and anti-inflammatory processes. Our results strongly suggest that ICA may be used as a potential agent to treat demyelination via regulating Nrf2/HO-1-mediated antioxidative stress and TLR4/NF-κB-mediated inflammatory responses.


Asunto(s)
Antioxidantes , Enfermedades Desmielinizantes , Flavonoides , Humanos , Antioxidantes/farmacología , Cuprizona/farmacología , Receptor Toll-Like 4 , FN-kappa B , Factor 2 Relacionado con NF-E2 , Antiinflamatorios/farmacología , Citocinas , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/tratamiento farmacológico
18.
J Integr Plant Biol ; 66(4): 731-748, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38482956

RESUMEN

Soil salinity has a major impact on rice seed germination, severely limiting rice production. Herein, a rice germination defective mutant under salt stress (gdss) was identified by using chemical mutagenesis. The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9. Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress. OsHAK9 is highly expressed in germinating seed embryos. Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K+ efflux in salt-exposed germinating seeds for the balance of K+/Na+. Disruption of OsHAK9 significantly reduced gibberellin 4 (GA4) levels, and the germination defective phenotype of oshak9a was partly rescued by exogenous GA3 treatment under salt stress. RNA sequencing (RNA-seq) and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress, and the expression of OsGA2ox7 was significantly inhibited by salt stress. Null mutants of OsGA2ox7 created using clustered, regularly interspaced, short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress. Overall, our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7, which provides a novel clue about the relationship between GA and OsHAKs in rice.


Asunto(s)
Giberelinas , Oryza , Giberelinas/farmacología , Giberelinas/metabolismo , Germinación/fisiología , Potasio/metabolismo , Oryza/metabolismo , Semillas/metabolismo , Estrés Salino , Proteínas de Transporte de Membrana/metabolismo , Regulación de la Expresión Génica de las Plantas
19.
Am J Orthod Dentofacial Orthop ; 165(4): 423-433, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38127040

RESUMEN

INTRODUCTION: This study aimed to evaluate the incidence and distribution of alveolar bone dehiscence and fenestration in skeletal Class III malocclusions with different vertical growth patterns in the anterior region using cone-beam computed tomography (CBCT). METHODS: In this retrospective study, 84 patients with skeletal Class III malocclusions who underwent CBCT were selected. This study included 28 patients with hypodivergence (mean age, 22.9 ± 3.9 years), 28 with normodivergence (mean age, 21.0 ± 3.0 years), and 28 with hyperdivergence (mean age, 21.0 ± 3.7 years). Teeth in the anterior region were examined using CBCT to detect dehiscence and fenestration. The incidences of dehiscence and fenestration in the anterior teeth region were recorded, and statistical analysis was conducted using SPSS software (version 25.0, IBM, Armonk, NY). RESULTS: Among the patients with skeletal Class III malocclusions, dehiscence and fenestration were prone to occur in the mandible. Dehiscence and fenestration were more prevalent in patients with hyperdivergence compared with in patients with hypodivergence and normodivergence. CONCLUSIONS: Dehiscence and fenestration are prevalent among patients with skeletal Class III malocclusion. Furthermore, the occurrence of alveolar bone defects is higher in patients with hyperdivergence.


Asunto(s)
Proceso Alveolar , Maloclusión de Angle Clase III , Humanos , Adulto Joven , Adulto , Adolescente , Estudios Retrospectivos , Proceso Alveolar/diagnóstico por imagen , Maloclusión de Angle Clase III/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Mandíbula/diagnóstico por imagen
20.
Zhongguo Zhong Yao Za Zhi ; 49(1): 162-174, 2024 Jan.
Artículo en Zh | MEDLINE | ID: mdl-38403349

RESUMEN

This study aims to investigate whether tetramethylpyrazine(TMP) can stimulate angiogenesis in cerebral microvascular endothelial cells and alleviate cerebral ischemic stroke(CIS) and to explore the underlying mechanisms. In the animal study, adult Sprague-Dawley rats(n=15) were assigned into sham surgery(sham), middle cerebral artery occlusion/reperfusion(MCAO/R), and MCAO/R+TMP(intraperitoneal injection of 20 mg·kg~(-1)) groups. The neurological function was evaluated by the Z-Longa method. The cerebral infarction volume was detected by TTC staining. Enzyme-linked immunosorbent assay(ELISA) was employed to detect the expression of vascular endothelial growth factor(VEGF), angiopoietin(Ang), and platelet-derived growth factor(PDGF). Immunofluorescence staining was employed to detect Ki67 and the expression of vascular endothelial growth factor A(VEGFA) and slient information regulator 1(SIRT1). Western blot was employed to determine the expression levels of VEGFA, SIRT1, angiopoietin-2(Ang-2), and platelet-derived growth factor B(PDGFB). In the cell study, mouse brain-derived endothelial cells(Bend.3) were cultured, and the optimal concentration of TMP was determined. Then, VEGF, Ang, and PDGF were detected by ELISA after the addition of cabozantinib. Western blot was employed to measure the expression of VEGFA, Ang-2, and PDGFB. Immunofluorescence staining was used to detect CD31, CD34, and Ki67, and the proliferation, migration, and tube formation ability of Bend.3 cells were observed in vitro. Western blot and immunofluorescence staining were performed to measure the expression of SIRT1 and VEGFA after addition of the SIRT1-specific inhibitor selisistat(EX-527). The results showed that compared with the sham group, the MCAO/R group had severe neurological function damage, increased infarction volume, up-regulated expression of VEGF, VEGFA, Ang, Ang-2, PDGF, and PDGFB, and down-regulated expression of Ki67 and SIRT1(P<0.01). Compared with the MCAO/R group, the MCAO/R+TMP group presented alleviated neurological function damage, reduced infarction volume, and activated expression of VEGF, VEGFA, Ang, Ang-2, PDGF, PDGFB, Ki67, and SIRT1(P<0.01). The cell experiments showed that compared with the normal group, Bend.3 cells were activated by oxygen glucose deprivation/reoxygenation(OGD/R) treatment(P<0.05, P<0.01). Compared with the OGD/R group, the OGD/R+TMP group upregulated the expression levels of VEGF, VEGFA, Ang, Ang-2, PDGF, PDGFB, SIRT1, Ki67, CD31, and CD34, enhanced the angiogenic ability of Bend.3 cells without being inhibited by BMS or EX-527(P<0.05, P<0.01, P<0.001). The results suggest that TMP can activate the SIRT1/VEGFA signaling pathway to stimulate angiogenesis and alleviate CIS injury.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Pirazinas , Accidente Cerebrovascular , Ratas , Animales , Ratones , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Células Endoteliales/metabolismo , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Ratas Sprague-Dawley , Proteínas Proto-Oncogénicas c-sis , Sirtuina 1/genética , Sirtuina 1/metabolismo , Angiogénesis , Antígeno Ki-67/metabolismo , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/genética , Transducción de Señal , Infarto de la Arteria Cerebral Media
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