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1.
Sensors (Basel) ; 24(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732791

RESUMO

This study investigates the impact of varying side wind velocities and nozzle inclination angles on droplet penetration during plant protection spraying operations, focusing on citrus trees. Experiments were conducted across four wind speed levels (0, 1, 2, 3 m/s) perpendicular to the nozzle direction and seven nozzle inclination levels (0°, 8°, 15°, 23°, 30°, 38°, 45°) to evaluate droplet distribution under different spraying parameters. A baseline condition with 0 m/s wind speed and a 0° nozzle angle served as the control. Utilizing Computational Fluid Dynamics (CFD) and regression analysis techniques in conjunction with field trials, the droplet penetration was analyzed. Results indicate that at constant wind speeds, adjusting the nozzle inclination angle against the direction of the side wind can significantly enhance droplet deposition in the canopy, with a 23° inclination providing the optimal increase in deposition volume, averaging a change of +16.705 µL/cm2. Multivariate nonlinear regression analysis revealed that both wind speed and nozzle inclination angle significantly affect the droplet penetration ratio, demonstrating a correlation between these factors, with wind speed exerting a greater impact than nozzle angle. Increasing the nozzle inclination angle at higher wind speeds improves the penetration ratio, with the optimal parameters being a 23° angle and 3 m/s wind speed, showing a 12.6% improvement over the control. The model fitted for the impact of nozzle angle and wind speed on droplet penetration was validated through field experiments, identifying optimal angles for enhancing penetration at wind speeds of 1, 2, and 3 m/s as 8°, 17°, and 25°, respectively. This research provides insights for improving droplet penetration techniques in plant protection operations.

2.
Int J Biol Macromol ; 266(Pt 1): 130998, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521332

RESUMO

Although calcium­magnesium phosphate cements (CMPCs) have been widely applied to treating critical-size bone defects, their repair efficiency is unsatisfactory owing to their weak surface bioactivity and uncontrolled ion release. In this study, we lyophilized alginate sodium (AS) as a coating onto HAp/K-struvite (H@KSv) to develop AS/HAp/K-struvite (AH@KSv), which promotes bone regeneration. The compressive strength and hydrophilicity of AH@KSv significantly improved, leading to enhanced cell adhesion in vitro. Importantly, the SA coating enables continuous ions release of Mg2+ and Ca2+, finally leading to enhanced osteogenesis in vitro/vivo and different patterns of new bone ingrowth in vivo. Furthermore, these composites increased the expression levels of biomarkers of the TRPM7/PI3K/Akt signaling pathway via an equilibrium effect of Mg2+ to Ca2+. In conclusion, our study provides novel insights into the mechanisms of Mg-based biomaterials for bone regeneration.


Assuntos
Alginatos , Cimentos Ósseos , Regeneração Óssea , Fosfatos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Canais de Cátion TRPM , Regeneração Óssea/efeitos dos fármacos , Canais de Cátion TRPM/metabolismo , Alginatos/química , Alginatos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Fosfatos/química , Fosfatos/farmacologia , Cimentos Ósseos/química , Cimentos Ósseos/farmacologia , Osteogênese/efeitos dos fármacos , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Adesão Celular/efeitos dos fármacos , Propriedades de Superfície , Camundongos , Ratos , Força Compressiva
3.
Transl Oncol ; 39: 101802, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37839175

RESUMO

BACKGROUND: Serpin Family H Member 1 (SERPINH1) may be involved in the regulation of occurrence and development of tumors. However, the role and mechanism of SERPINH1 in osteosarcoma remain poorly understood. The aim of this study is to investigate the expression and role of SRPINH1 in osteosarcoma and to elucidate its underlying mechanisms. METHODS: First, we examined the expression of SERPINH1 in osteosarcoma and analyzed publicly available datasets to investigate whether SERPINH1 expression was associated with the prognosis of osteosarcoma. Then we constructed SERPINH1 overexpression and knockdown systems in osteosarcoma cells, and examined the proliferation, migration and invasion ability of osteosarcoma cells after SERPINH1 expression changes using CCK-8 assay, wound healing assay and transwell invasion assay. In addition, we constructed a subcutaneous xenograft tumor model to study the function of SERPINH1 in vivo. We also examined the downstream pathways of SERPINH1 by functional analysis and performed subsequent validation. RESULTS: SERPINH1 was upregulated and associated with poor survival in patients with osteosarcoma. SERPINH1 promoted the proliferation, migration and invasion of osteosarcoma cells and promotes the growth of osteosarcoma in vivo by activating the PI3K-Akt signaling pathway. CONCLUSION: SERPINH1 partakes in the biological process of osteosarcoma as a tumor promotor and may be an emerging biomarker in osteosarcoma.

4.
BMC Cancer ; 23(1): 1179, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041020

RESUMO

BACKGROUND: Osteosarcoma (OS) is the most common primary malignancy of bone tumors. More and more ARHGAP family genes have been confirmed are to the occurrence, development, and invasion of tumors. However, its significance in osteosarcoma remains unclear. In this study, we aimed to identify the relationship between ARHGAP family genes and prognosis in patients with OS. METHODS: OS samples were retrieved from the TCGA and GEO databases. We then performed LASSO regression analysis and multivariate COX regression analysis to select ARHGAP family genes to construct a risk prognosis model. We then validated this prognostic model. We utilized ESTIMATE and CIBERSORT algorithms to calculate the stroma and immune scores of samples, as well as the proportions of tumor infiltrating immune cells (TICs). Finally, we conducted in vivo and in vitro experiments to investigate the effect of ARHGAP28 on osteosarcoma. RESULTS: We selected five genes to construct a risk prognosis model. Patients were divided into high- and low-risk groups and the survival time of the high-risk group was lower than that of the low-risk group. The high-risk group in the prognosis model constructed had relatively poor immune function. GSEA and ssGSEA showed that the low-risk group had abundant immune pathway infiltration. The overexpression of ARHGAP28 can inhibit the proliferation, migration, and invasion of osteosarcoma cells and tumor growth in mice, and IHC showed that overexpression of ARHGAP28 could inhibit the proliferation of tumor cells. CONCLUSION: We constructed a risk prognostic model based on five ARHGAP family genes, which can predict the overall survival of patients with osteosarcoma, to better assist us in clinical decision-making and individualized treatment.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Animais , Camundongos , Prognóstico , Osteossarcoma/genética , Fatores de Risco , Algoritmos , Neoplasias Ósseas/genética
5.
Biomedicines ; 12(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38255182

RESUMO

Bone defect repair poses significant challenges in orthopedics, thereby increasing the demand for bone substitutes. Magnesium phosphate cements (MPCs) are widely used for bone defect repair because of their excellent mechanical properties and biodegradability. However, high crystallinity and uncontrolled magnesium ion (Mg2+) release limit the surface bioactivity of MPCs in bone regeneration. Here, we fabricate chondroitin sulfate (CS) as a surface coating via the lyophilization method, namely CMPC. We find that the CS coating is uniformly distributed and improves the mechanical properties of MPC through anionic electrostatic adsorption, while mediating degradation-related controlled ion release of Mg2+. Using a combination of in vitro and in vivo analyses, we show that the CS coating maintained cytocompatibility while increasing the cell adhesion area of MC3T3-E1s. Furthermore, we display accelerated osteogenesis and angiogenesis of CMPC, which are related to appropriate ion concentration of Mg2+. Our findings reveal that the preparation of a lyophilized CS coating is an effective method to promote surface bioactivity and mediate Mg2+ concentration dependent osteogenesis and angiogenesis, which have great potential in bone regeneration.

6.
J Bone Oncol ; 37: 100461, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36419799

RESUMO

T-cell lymphoma invasion and metastasis 2 (TIAM2) plays a critical role in the malignancy development of many human cancers. However, the specific regulatory mechanism of TIAM2 in osteosarcoma has not yet been explored. In this study, we investigated how TIAM2 affects the proliferation and invasion of osteosarcoma cells and the underlying molecular mechanism. We performed data mining of publicly available datasets to examine whether the expression of TIAM2 is associated with osteosarcoma. We knocked down the expression of and overexpressed TIAM2 in osteosarcoma cells. The proliferative capacity of cells in each group was determined by the Cell Counting Kit-8 assay. Wound healing and Transwell invasion assays were performed to evaluate the migration and invasion abilities of the TIAM2 knockdown and overexpressed osteosarcoma cells. Determination of the function of TIAM2 in vivo was performed in nude mice. Data mining confirmed that TIAM2 expression is associated with poor prognosis in osteosarcoma. TIAM2 expression levels were significantly higher in osteosarcoma cells, and TIAM2 expression knockdown reduced proliferation and invasion abilities. Animal experiments demonstrated that TIAM2 promotes tumor growth. Additional experiments suggested that TIAM2 was significantly related to the activation of the JAK2/STAT3 pathway, and subsequent mechanistic experiments further confirmed this. Our findings suggest that TIAM2 promotes the proliferation and invasion capacities of osteosarcoma cells by activating the JAK2/STAT3 signaling pathway. TIAM2 may serve as a potential prognostic target for patients with OS.

7.
Psychopharmacology (Berl) ; 239(11): 3579-3593, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36221038

RESUMO

RATIONALE: Tau hyperphosphorylation and aggregation is considered as a main pathological mechanism underlying Alzheimer's disease (AD). Rose Bengal (RB) is a synthetic dye used for disease diagnosis, which was reported to inhibit tau toxicity via inhibiting tau aggregation in Drosophila. However, it was unknown if RB could produce anti-AD effects in rodents. OBJECTIVES: The research aimed to investigate if and how RB could prevent ß-amyloid (Aß) oligomers-induced tau hyperphosphorylation in rodents. METHODS AND RESULTS: RB was tested in vitro (0.3-1 µM) and prevented Aß oligomers-induced tau hyperphosphorylation in PC12 cells. Moreover, RB (10-30 mg/kg, i.p.) effectively attenuated cognitive impairments induced by Aß oligomers in mice. Western blotting analysis demonstrated that RB significantly increased the expression of pSer473-Akt, pSer9-glycogen synthase kinase-3ß (GSK3ß) and reduced the expression of cyclin-dependent kinase 5 (CDK5) both in vitro and in vivo. Molecular docking analysis suggested that RB might directly interact with GSK3ß and CDK5 by acting on ATP binding sites. Gene Ontology enrichment analysis indicated that RB might act on protein phosphorylation pathways to inhibit tau hyperphosphorylation. CONCLUSIONS: RB was shown to inhibit tau neurotoxicity at least partially via inhibiting the activity of GSK3ß and CDK5, which is a novel neuroprotective mechanism besides the inhibition of tau aggregation. As tau hyperphosphorylation is an important target for AD therapy, this study also provided support for investigating the drug repurposing of RB as an anti-AD drug candidate.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Ratos , Camundongos , Animais , Peptídeos beta-Amiloides/toxicidade , Peptídeos beta-Amiloides/metabolismo , Quinase 5 Dependente de Ciclina/metabolismo , Proteínas tau/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rosa Bengala/uso terapêutico , Glicogênio Sintase Quinase 3 beta/metabolismo , Simulação de Acoplamento Molecular , Doença de Alzheimer/tratamento farmacológico , Fosforilação , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/uso terapêutico
8.
Bioorg Chem ; 116: 105387, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34628225

RESUMO

Alzheimer's disease (AD) is a prevalent neurodegenerative disorder that has multiple causes. Therefore, multiple-target-directed ligands (MTDLs), which act on multiple targets, have been developed as a novel strategy for AD therapy. In this study, novel drug candidates were designed and synthesized by the covalent linkings of tacrine, a previously used anti-AD acetylcholinesterase (AChE) inhibitor, and dipicolylamine, an ß-amyloid (Aß) aggregation inhibitor. Most tacrine-dipicolylamine dimers potently inhibited AChE and Aß1-42 aggregation in vitro, and 13a exhibited nanomolar level inhibition. Molecular docking analysis suggested that 13a could interact with the catalytic active sites and the peripheral anion site of AChE, and bind to Aß1-42 pentamers. Moreover, 13a effectively attenuated Aß1-42 oligomers-induced cognitive dysfunction in mice by activating the cAMP-response element binding protein/brain-derived neurotrophic factor signaling pathway, decreasing tau phosphorylation, preventing synaptic toxicity, and inhibiting neuroinflammation. The safety profile of 13a in mice was demonstrated by acute toxicity experiments. All these results suggested that novel tacrine-dipicolylamine dimers, especially 13a, have multi-target neuroprotective and cognitive-enhancing potentials, and therefore might be developed as MTDLs to combat AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Aminas/farmacologia , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Fármacos Neuroprotetores/farmacologia , Ácidos Picolínicos/farmacologia , Tacrina/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/metabolismo , Aminas/química , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Ligantes , Estrutura Molecular , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/metabolismo , Ácidos Picolínicos/química , Agregados Proteicos/efeitos dos fármacos , Relação Estrutura-Atividade , Tacrina/química
9.
Int Immunopharmacol ; 97: 107656, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33895476

RESUMO

OBJECTIVES: This study was aimed to investigate the neuroprotective effects of 9-methylfascaplysin, a novel marine derivative derived from sponge, against middle cerebral artery occlusion/reperfusion (MCAO)-induced motor impairments, neuroinflammation and oxidative stress in rats. METHODS: Neurological and behavioral tests were used to evaluate behavioral changes. The 2, 3, 5-triphenyltetrazolium chloride staining was used to determine infarct size and edema extent. Activated microglia/macrophage was analyzed by immunohistochemical staining of Iba-1. RT-PCR and ELISA were used to measure the expression of inducible nitric oxide synthase, tumor necrosis factor-α, interleukin-1ß, CD16 and CD206. Western blotting analysis was performed to explore the activation of nuclear factor-κB (NF-κB) and NLRP3. The levels of oxidative stress were studied by evaluating the activities of superoxide dismutase, catalase and glutathione peroxidase. RESULTS: Post-occlusion intracerebroventricular injection of 9-methylfascaplysin significantly attenuated motor impairments and infarct size in MCAO rats. Moreover, 9-methylfascaplysin reduced the activation of microglia/macrophage in ischemic penumbra as evidenced by the decreased Iba-1-positive area and the reduced expression of pro-inflammatory factors. Furthermore, 9-methylfascaplysin inhibited MCAO-induced oxidative stress and activation of NF-κB and NLRP3 inflammasome. CONCLUSION: All the results suggested that 9-methylfascaplysin might produce neuroprotective effects against MCAO via the reduction of oxidative stress and neuroinflammation, simultaneously, possibly via the inhibition of NF-κB and NLRP3 inflammasome.


Assuntos
Indóis/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Animais , Modelos Animais de Doenças , Humanos , Indóis/uso terapêutico , Infarto da Artéria Cerebral Média/imunologia , Infarto da Artéria Cerebral Média/patologia , Inflamassomos/antagonistas & inibidores , Inflamassomos/metabolismo , Masculino , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doenças Neuroinflamatórias/imunologia , Doenças Neuroinflamatórias/patologia , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/imunologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
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