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1.
Small ; 20(27): e2309302, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38372497

RESUMO

Metal-organic framework materials are ideal materials characterized by open frameworks, adjustable components, and high catalytic activity. They are extensively utilized for catalysis. Due to decomposition and structural collapse under high temperatures and an oxygen-rich environment, the potential of thermal catalysis is greatly limited. In this research, Co-rich hollow spheres (Co-HSs) with a gradient composition are designed and synthesized to investigate their thermal catalytic properties in the ammonium perchlorate(AP)system. The results demonstrate that Co-HSs@AP exhibits good thermal catalytic activity and a high-temperature decomposition of 292.5 °C, which is 121.6 °C lower than pure AP. The hierarchical structure confers structural stability during the thermal decomposition process. Thermogravimetry-infrared indicates that the inclusion of Co-HSs successfully boosts the level of reactive oxygen species and achieves thorough oxidation of NH3. Based on the above phenomenon, macro dynamics calculations are carried out. The results show that Co-HSs can promote the circulation of lattice oxygen and reactive oxygen species and the multidimensional diffusion of NH3 in an oxygen-rich environment. This material has significant potential for application in the fields of thermal catalysis and ammonia oxidation.

2.
Arch Virol ; 169(5): 105, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637359

RESUMO

In this study, we identified a novel double-strand RNA (dsRNA) mycovirus in Pyricularia oryzae, designated "Magnaporthe oryzae partitivirus 4" (MoPV4). The genome of MoPV4 consists of a dsRNA-1 segment encoding an RNA-dependent RNA polymerase (RdRP) and a dsRNA-2 segment encoding a capsid protein (CP). Phylogenetic analysis indicated that MoPV4 belongs to the genus Gammapartitivirus within family Partitiviridae. The particles of MoPV4 are isometric with a diameter of about 32.4 nm. Three-dimensional structure predictions indicated that the RdRP of MoPV4 forms a classical right-handed conformation, while the CP has a reclining-V shape.


Assuntos
Ascomicetos , Micovírus , Vírus de RNA , RNA Viral/genética , Filogenia , Vírus de RNA/genética , Proteínas do Capsídeo/genética , RNA Polimerase Dependente de RNA/genética , Genoma Viral , Micovírus/genética , RNA de Cadeia Dupla/genética , Fases de Leitura Aberta
3.
J Clin Periodontol ; 51(7): 818-839, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38414291

RESUMO

AIM: Blood-brain barrier (BBB) disorder is one of the early findings in cognitive impairments. We have recently found that Porphyromonas gingivalis bacteraemia can cause cognitive impairment and increased BBB permeability. This study aimed to find out the possible key virulence factors of P. gingivalis contributing to the pathological process. MATERIALS AND METHODS: C57/BL6 mice were infected with P. gingivalis or gingipains or P. gingivalis lipopolysaccharide (P. gingivalis LPS group) by tail vein injection for 8 weeks. The cognitive behaviour changes in mice, the histopathological changes in the hippocampus and cerebral cortex, the alternations of BBB permeability, and the changes in Mfsd2a and Cav-1 levels were measured. The mechanisms of Ddx3x-induced regulation on Mfsd2a by arginine-specific gingipain A (RgpA) in BMECs were explored. RESULTS: P. gingivalis and gingipains significantly promoted mice cognitive impairment, pathological changes in the hippocampus and cerebral cortex, increased BBB permeability, inhibited Mfsd2a expression and up-regulated Cav-1 expression. After RgpA stimulation, the permeability of the BBB model in vitro increased, and the Ddx3x/Mfsd2a/Cav-1 regulatory axis was activated. CONCLUSIONS: Gingipains may be one of the key virulence factors of P. gingivalis to impair cognition and enhance BBB permeability by the Ddx3x/Mfsd2a/Cav-1 axis.


Assuntos
Barreira Hematoencefálica , Cisteína Endopeptidases Gingipaínas , Camundongos Endogâmicos C57BL , Porphyromonas gingivalis , Fatores de Virulência , Animais , Porphyromonas gingivalis/patogenicidade , Barreira Hematoencefálica/microbiologia , Camundongos , Fatores de Virulência/metabolismo , Adesinas Bacterianas/metabolismo , Masculino , Modelos Animais de Doenças , Permeabilidade , Disfunção Cognitiva/microbiologia , Disfunção Cognitiva/metabolismo , Hipocampo/metabolismo , Infecções por Bacteroidaceae/microbiologia , Infecções por Bacteroidaceae/complicações
4.
Small ; 19(20): e2207023, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36642801

RESUMO

The design of highly dispersed active sites of hollow materials and unique contact behavior with the components to be catalyzed provide infinite possibilities for exploring the limits of catalyst capacity. In this study, the synthesis strategy of highly open 3-dimensional frame structure Prussian blue analogues (CoFe-PBA) was explored through structure self-transformation, which was jointly guided by template mediated epitaxial growth, restricted assembly and directional assembly. Additionally, good application prospect of CoFe-PBA as combustion catalyst was discussed. The results show that unexpected thermal decomposition behavior can be achieved by limiting AP(ammonium perchlorate) to the framework of CoFe-PBA. The high temperature decomposition stage of AP can be advanced to 283.6 °C and the weight loss rate can reach 390.03% min-1 . In-situ monitoring shows that CoFe-PBA can accelerate the formation of NO and NO2 . The calculation of reaction kinetics proved that catalytic process was realized by increasing the nucleation factor. On this basis, the catalytic mechanism of CoFe-PBA on the thermal decomposition of AP was discussed, and the possible interaction process between AP and CoFe-PBA during heating was proposed. At the same time, another interesting functional behavior to prevent AP from caking was discussed.

5.
Sensors (Basel) ; 23(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37765820

RESUMO

The vulnerable road users (VRUs), being small and exhibiting random movements, increase the difficulty of object detection of the autonomous emergency braking system for vulnerable road users AEBS-VRUs, with their behaviors highly random. To overcome existing problems of AEBS-VRU object detection, an enhanced YOLOv5 algorithm is proposed. While the Complete Intersection over Union-Loss (CIoU-Loss) and Distance Intersection over Union-Non-Maximum Suppression (DIoU-NMS) are fused to improve the model's convergent speed, the algorithm also incorporates a minor object detection layer to increase the performance of VRU detection. A dataset for complex AEBS-VRUS scenarios is established based on existing datasets such as Caltech, nuScenes, and Penn-Fudan, and the model is trained using migration learning based on the PyTorch framework. A number of comparative experiments using models such as YOLOv6, YOLOv7, YOLOv8 and YOLOx are carried out. The results of the comparative evaluation show that the proposed improved YOLO5 algorithm has the best overall performance in terms of efficiency, accuracy and timeliness of target detection.

6.
Prep Biochem Biotechnol ; 53(8): 978-987, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36719813

RESUMO

In this paper, the total phenylethanosides (TPS) were extracted efficiently by an innovative extraction technology--deep eutectic solvent-based ultrasound-assisted extraction (DES-UAE) from Plantago asiatica L. Ten diverse types of DESs were synthesized as alternative extraction solutions. The extraction efficiency of DES-3 (constituted by choline chloride and lactic acid) was much higher than those of other DESs. On the basis of single factor tests and Box-Behnken design (BBD), the optimum processing parameters of DES-UAE as follow: DES-3 with molar ratio of 1:3, extraction temperature 51 °C, solid/liquid 22.5 mg/ml, water content 30%, ultrasonic power 65 W, extraction time 23 min. The extraction efficiency of TPS from Plantago asiatica L. was 8.395 mg/ml, which was more superior than those of organic solvents (water, methanol, 50% methanol, ethanol, 50% ethanol). The extraction kinetics experiment results showed that water content had a significant influence upon the extraction efficiency of TPS. At the same time, AB-8 macroporous resin column was used to efficiently isolate TPS from DES extraction with a recovery rate of 88.5%.


Assuntos
Flavonoides , Plantago , Solventes , Solventes Eutéticos Profundos , Metanol , Cinética , Água , Tecnologia , Etanol , Extratos Vegetais
7.
BMC Oral Health ; 23(1): 736, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37814304

RESUMO

BACKGROUND: Periodontitis is a chronic and multi-factorial infectious disease. A notable difference exists in the prognosis of patients with severe periodontitis after non-surgical periodontal treatment. Thus, a retrospective study was conducted to identify common and specific factors that impact the prognosis of patients with periodontitis stage III-IV following non-surgical periodontal treatment at different tooth sites. METHODS: A total of 977 teeth were included in the study, comprising 266 patients diagnosed with periodontitis stage III-IV. This sample included 330 anterior teeth, 362 maxillary posterior teeth, and 285 mandibular posterior teeth. Following treatment, the teeth were categorized into two groups based on residual pocket depth [probing depth (PD) ≥ 5 mm] at 3 months post-treatment. The prognosis of periodontitis stage III-IV was assessed through multivariate analysis employing logistic regression to determine the association of various risk factors. RESULTS: The PD values of each site and the deepest PD values of each tooth significantly decreased at 3 months post-treatment. Residual pockets were predominantly found in the mesio/disto-buccal and mesio/disto-lingual regions. Multivariate analysis revealed that gender, PD, sulcus bleeding index (SBI) and plaque index (PLI) at baseline, and crown-root ratio in anterior teeth had a significant influence on periodontitis stage III-IV (P < 0.05). Smoking, PD, PLI and furcation involvement (FI) at baseline, PLI at 3 months post-treatment, grades of periodontitis, and crown-root ratio were prediction factors for maxillary posterior teeth. Factors such as PD, PLI and FI at baseline, PLI at 3 months post-treatment, and crown-root were significant in mandibular posterior teeth. CONCLUSIONS: The outcome of non-surgical treatment varies depending on the tooth positions for patients with periodontitis stage III-IV. Dentists must accurately identify the affected teeth that have periodontal pockets of more than 5 mm, taking into consideration the positions of the affected teeth, as well as various local and systemic factors. This comprehensive assessment will enable dentists to develop a customized and effective treatment plan.


Assuntos
Periodontite , Dente , Humanos , Estudos Retrospectivos , Periodontite/terapia , Periodontite/cirurgia , Bolsa Periodontal/terapia , Resultado do Tratamento
8.
BMC Neurol ; 22(1): 448, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460992

RESUMO

BACKGROUND: Inflammatory myofibroblastic tumor (IMT) is a rare central nervous system (CNS) tumor. We first report a rare case of IMT in the lateral ventricle and describe the magnetic resonance imaging (MRI) findings of the tumor with an emphasis on the advanced MRI features. CASE PRESENTATION: A 49-year-old female patient with headaches and blurred vision for 2 months. Brain MRI revealed a well-circumscribed, lobulated mass occupying the left lateral ventricle trigone, with marked perilesional brain edema. The tumor showed heterogeneous significant hyperintensity on T2-weighted imaging (T2WI) and hypointensity on T1-weighted imaging (T1WI). After the administration of gadolinium, the mass exhibited marked contrast enhancement and the halo sign was observed. On advanced MRI, the lesion showed decreased perfusion on perfusion MRI and reduced diffusion on diffusion-weighted imaging (DWI). On susceptibility-weighted imaging (SWI), there was a punctate low signal intensity in the tumor. The patient underwent surgical resection of the mass and a pathological examination confirmed the lesion to be an inflammatory myofibroblastic tumor with negative expression of anaplastic lymphoma kinase (ALK). This patient had remained healthy without evidence of recurrence during a 20-month follow-up. CONCLUSIONS: On MRI, marked perilesional brain edema, significant hyperintensity on T2WI, hypoperfusion on perfusion MRI but with an obvious enhancement, no diffusion restriction on DWI, and halo sign may be the characteristic findings of intraventricular IMT. The advanced MRI characteristics could provide abundant information to reflect the histological features and physiological metabolic characteristics of the tumor.


Assuntos
Edema Encefálico , Feminino , Humanos , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética , Gadolínio , Imagem de Difusão por Ressonância Magnética , Angiografia por Ressonância Magnética
9.
Phytochem Anal ; 33(1): 94-104, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34137102

RESUMO

INTRODUCTION: In the present study, ternary deep eutectic solvent-based ultrasound-assisted extraction was developed for the efficient extraction of plantamajoside, acteoside, quercetin and kaempferol from Plantago asiatica L. METHODOLOGY: Six kinds of choline chloride-based ternary deep eutectic solvents (TDESs) were prepared as potential extraction solutions. In order to obtain optimal extraction efficiency, a series of extraction conditions were investigated by single-factor test and orthogonal test. RESULTS: The extraction efficiency of choline chloride/lactic acid/ethylene glycol (ChCl-LA-EG) was much higher than that of other TDESs. ChCl-LA-EG-11 synthesised with choline chloride, lactic acid and ethylene glycol (1:4:2) was considered to have a higher extraction efficiency. The optimal ultrasound-assisted extraction conditions were as follows: water content in ChCl-LA-EG-11, 50%; extraction temperature, 70°C; ratio of solid/liquid, 20 mg/mL; ultrasonic power, 60 W; extraction time, 35 min; pH of the solution, 8. Under the optimal extraction conditions, the extraction efficiencies of plantamajoside, acteoside, quercetin and kaempferol were 3.83 ± 0.41, 4.23 ± 0.45, 0.56 ± 0.15 and 0.19 ± 0.08 mg/g, respectively. The extraction efficiency of the total target components was 9.21 ± 0.63 mg/g, which was much higher than that of conventional solvents (water, methanol, ethanol, 50% methanol, 50% ethanol). The target components were isolated efficiently from the TDES solution by an AB-8 macroporous resin column with a recovery rate of 95.6%. CONCLUSION: This study demonstrated that TDESs possessed excellent physical and chemical properties and had enormous potential for active component extraction of traditional Chinese medicinal materials.


Assuntos
Plantago , Quercetina , Catecóis , Solventes Eutéticos Profundos , Glucosídeos , Quempferóis , Fenóis , Solventes
10.
Oral Dis ; 27(7): 1775-1788, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33098722

RESUMO

OBJECTIVES: This paper aims to study the effect of the active form of vitamin D (calcitriol) on the internalized Porphyromonas gingivalis in macrophages and to assess the role of autophagy during this process. MATERIALS AND METHODS: Quantitative RT-PCR and bacteria culture were used to quantify live P. gingivalis internalized into U937-derived macrophages. Western blot assays were performed to detect the effect of P. gingivalis and calcitriol on autophagy in macrophages. Transmission electron microscope was used to observe the effect of calcitriol on the status of internalized P. gingivalis. Colocalization of P. gingivalis with the autophagosome and lysosome markers was observed by confocal laser scanning microscopy. RESULTS: Calcitriol caused a dose-dependent decrease in live P. gingivalis numbers and promoted both the endogenous and P. gingivalis-induced autophagy in macrophages. Calcitriol significantly promoted the destruction of P. gingivalis and the colocalization of P. gingivalis with autophagosome and lysosome markers. Conversely, with 3-MA, live P. gingivalis numbers in macrophages increased significantly and inhibition effect of calcitriol on the number of live P. gingivalis was attenuated. CONCLUSION: In U937-derived macrophages, calcitriol may promote colocalization of P. gingivalis with autophagosomes and lysosomes, namely autophagy process, to degrade live P. gingivalis.


Assuntos
Porphyromonas gingivalis , Vitamina D , Autofagossomos , Autofagia , Macrófagos , Vitamina D/farmacologia
11.
J Exp Bot ; 71(3): 1128-1138, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31639819

RESUMO

Agarwood is derived from wounds in Aquilaria trees and is widely used in traditional medicine, incense, and perfume. Sesquiterpenes are one of the main active components in agarwood and are known to be induced by wounding or injury; However, the molecular mechanisms by which wounding leads to sesquiterpene formation remain largely unknown. Agarwood sesquiterpene synthase 1 (ASS1) is one of key enzymes responsible for the biosynthesis of sesquiterpenes and is a crucial jasmonate (JA)-responsive wound-inducible synthase. However, it is not known why ASS1 is not expressed in healthy trees and how its expression is induced as a result of wounding. Here, we report that ASS1 is a wound-induced gene with a promoter in which a 242-bp region (-973 to -731bp) is identified as the core sequence for responding to wound signals. AsWRKY44 binds directly to this region and represses ASS1 promoter activity. Down-regulation or disruption of AsWRKY44 can relieve the inhibition and activate ASS1 expression. In addition, AsWRKY44 is degraded and the expression of ASS1 is significantly up-regulated in response to exogenous application of methyl jasmonate. Thus, AsWRKY44 is a crucial negative regulator of wound-induced ASS1 transcription, and is central to the mechanism of sesquiterpene biosynthesis in agarwood.


Assuntos
Sesquiterpenos/metabolismo , Thymelaeaceae/metabolismo , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas , Regiões Promotoras Genéticas , Thymelaeaceae/genética
12.
J Sci Food Agric ; 100(2): 560-569, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31588555

RESUMO

BACKGROUND: Preprocessing technologies of fresh tea leaves have a great influence on tea quality. A multifunctional preprocessing device for tea raw materials has been designed and utilized as a novel item of equipment to synchronously meet the process needs of spreading of green tea, withering of black tea and shaking of oolong tea. RESULTS: The preprocessing parameters of fresh tea leaves for spreading of green tea, withering of black tea and shaking of oolong tea were optimized by orthogonal experiments. Sensory assessment combined with statistical tools was employed as an analytical method to evaluate the pretreatment effect of processing different sorts of tea. The range analysis and variance analysis of tea sensory evaluation combined with chemical components (total polyphenols, free amino acids and soluble sugar) showed that A3 B2 C3 (70%, 25 °C, 8 h), A1 B3 C1 (60%, 28 °C, 18 h) and A1 B1 C3 (5 min, 20 °C, discontinuous leaf turning c) were considered to be the optimum schemes for the best pretreatment conditions of the above three major processing types of tea, respectively. The verification experiment of the proposed schemes was performed with satisfactory performance. CONCLUSION: This study demonstrated that a multifunctional preprocessing device for fresh tea leaves can be successfully applied to simultaneously estimate spreading of green tea, withering of black tea and shaking of oolong tea. © 2019 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Manipulação de Alimentos/instrumentação , Folhas de Planta/química , Chá/química , Aminoácidos/análise , Humanos , Polifenóis/análise , Paladar
13.
BMC Microbiol ; 18(1): 16, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29482504

RESUMO

BACKGROUND: Porphyromonas gingivalis (P. gingivalis), one of the main pathogenic bacteria involved in periodontitis, induces the expression of intercellular adhesion molecule - 1 (ICAM-1) and monocyte-endothelial cell adhesion. This effect plays a pivotal role in atherosclerosis development. Macrophage migration inhibitory factor (MIF) is a multifunctional cytokine and critically affects atherosclerosis pathogenesis. In this study, we tested the involvement of MIF in the P. gingivalis ATCC 33277-enhanced adhesive properties of endothelial cells. RESULTS: Endothelial MIF expression was enhanced by P. gingivalis ATCC 33277 infection. The MIF inhibitor ISO-1 inhibited ICAM-1 production in endothelial cells, and monocyte-endothelial cell adhesion was induced by P. gingivalis ATCC 33277 infection. However, the addition of exogenous human recombinant MIF to P. gingivalis ATCC 33277-infected endothelial cells facilitated monocyte recruitment by promoting ICAM-1 expression in endothelial cells. CONCLUSIONS: These experiments revealed that MIF in endothelial cells participates in the pro-atherosclerotic lesion formation caused by P. gingivalis ATCC 33277 infection. Our novel findings identify a more detailed pathological role of P. gingivalis ATCC 33277 in atherosclerosis.


Assuntos
Adesão Celular , Células Endoteliais/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Monócitos/metabolismo , Porphyromonas gingivalis/metabolismo , Sobrevivência Celular , Citocinas/metabolismo , Humanos , Oxirredutases Intramoleculares/metabolismo , Periodontite/microbiologia , Porphyromonas gingivalis/patogenicidade , Células THP-1
14.
Sensors (Basel) ; 18(12)2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30563274

RESUMO

To improve the accuracy of lane detection in complex scenarios, an adaptive lane feature learning algorithm which can automatically learn the features of a lane in various scenarios is proposed. First, a two-stage learning network based on the YOLO v3 (You Only Look Once, v3) is constructed. The structural parameters of the YOLO v3 algorithm are modified to make it more suitable for lane detection. To improve the training efficiency, a method for automatic generation of the lane label images in a simple scenario, which provides label data for the training of the first-stage network, is proposed. Then, an adaptive edge detection algorithm based on the Canny operator is used to relocate the lane detected by the first-stage model. Furthermore, the unrecognized lanes are shielded to avoid interference in subsequent model training. Then, the images processed by the above method are used as label data for the training of the second-stage model. The experiment was carried out on the KITTI and Caltech datasets, and the results showed that the accuracy and speed of the second-stage model reached a high level.

15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 49(3): 347-351, 2018 May.
Artigo em Chinês | MEDLINE | ID: mdl-30014632

RESUMO

OBJECTIVE: To determine the expression of miR-30b in hair cells of mice,and its regulatory effect on the target gene DNM1 and expression of Dynamin,the key protein of synaptic endocytosis in inner hair cells. METHODS: The basilar membrane of cochlear in adult C57 mice was obtained. The expression of miR-30b in the hair cells was detected by in situ hybridization. Luciferase vector was constructed and transfected into 293T cells with miR-30b. Changes in luciferase activity were measured to verify whether DNM1 was the target gene of miR-30b. Adeno-associated virus carrying miR-30b were micro-injected into cochlear via the round window membrane. mRNA expressions of DNM1 and miR-30b were detected by RT-PCR 14 days later. The expression of Dynamin was detected by Western blot. RESULTS: miR-30b expressed in the inner and outer hair cells scattered in the region of the nucleus and cytoplasm. miR-30b reduced luciferase activity from the reporter vector containing DNM11 (P<0.05),but not in its mutants. Increased expressions of miR-30b and decreased mRNA expressions of DNM1 and Dynamin were observed following transfection of AAV-miR-30b. CONCLUSION: miR-30b expresses in inner and outer hair cells,which is consistent with the morphological orientation of dynamin. miR-30b inhibits the expression of Dynamin by targeting DNM11 gene.


Assuntos
Dinaminas/metabolismo , Células Ciliadas Auditivas/metabolismo , MicroRNAs/metabolismo , Animais , Dinaminas/genética , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Transfecção
16.
PLoS Comput Biol ; 10(12): e1004004, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25501005

RESUMO

Vesicular stomatitis virus (VSV) is the prototype for negative sense non segmented (NNS) RNA viruses which include potent human and animal pathogens such as Rabies, Ebola and measles. The polymerases of NNS RNA viruses only initiate transcription at or near the 3' end of their genome template. We measured the dissociation constant of VSV polymerases from their whole genome template to be 20 pM. Given this low dissociation constant, initiation and sustainability of transcription becomes nontrivial. To explore possible mechanisms, we simulated the first hour of transcription using Monte Carlo methods and show that a one-time initial dissociation of all polymerases during entry is not sufficient to sustain transcription. We further show that efficient transcription requires a sliding mechanism for non-transcribing polymerases and can be realized with different polymerase-polymerase interactions and distinct template topologies. In conclusion, we highlight a model in which collisions between transcribing and sliding non-transcribing polymerases result in release of the non-transcribing polymerases allowing for redistribution of polymerases between separate templates during transcription and suggest specific experiments to further test these mechanisms.


Assuntos
RNA Polimerases Dirigidas por DNA/genética , Genes Virais/genética , RNA Viral/genética , Transcrição Gênica/genética , Vesiculovirus/genética , Proteínas Virais/genética , Biologia Computacional , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Modelos Genéticos , Modelos Moleculares , Método de Monte Carlo , RNA Viral/química , RNA Viral/metabolismo , Proteínas Virais/química , Proteínas Virais/metabolismo
17.
Heliyon ; 10(11): e31973, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38841516

RESUMO

Purpose: Endometrial cancer (EC) poses a serious risk to females worldwide; thus, a deep understanding of EC is urgently required. The role and mechanisms of gamma-glutamyltransferase light chain 1 (GGTLC1) in EC remain obscure. This study aims to elucidate the function and mechanisms underlying GGTLC1's involvement in EC. Methods: Bioinformatic tools and databases were used to analyze GGTLC1 and its associated gene expression in EC tissues. Functional enrichment explorations and immune infiltration analyses were conducted, together with investigation into the methylation status of GGTLC1. Western blotting and Quantitative real-time PCR quantified expression levels. Additional experimental methodologies elucidated the role of GGTLC1 in EC progression. Transcriptome sequencing identified potential regulatory pathways for GGTLC1, and tumor growth was evaluated in vivo using HEC-1A cells in nude mice. Results: GGTLC1 was upregulated and negatively correlated with immune cell infiltration and DNA methylation in EC. Cell migration and proliferation were reduced following GGTLC1 knockdown, together with arrest at the G0/G1 phase and an upsurge in apoptosis. Compared to the knockdown group, TGF-ß/Smad signaling pathway was up-regulated in the negative control group of EC cells by transcriptome analysis. The levels of TGF-ß, pSmad2, and pSmad3 followed the same decreasing trend, whereas Smad3 and Smad2 protein levels remained unchanged. Conclusion: Knockdown of GGTLC1 attenuates EC development through the TGF-ß/Smad pathway, positioning GGTLC1 as a promising target for EC treatment.

18.
MAbs ; 16(1): 2339582, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38666507

RESUMO

Understanding factors that affect the clustering and association of antibodies molecules in solution is critical to their development as therapeutics. For 19 different monoclonal antibody (mAb) solutions, we measured the viscosities, the second virial coefficients, the Kirkwood-Buff integrals, and the cluster distributions of the antibody molecules as functions of protein concentration. Solutions were modeled using the statistical-physics Wertheim liquid-solution theory, representing antibodies as Y-shaped molecular structures of seven beads each. We found that high-viscosity solutions result from more antibody molecules per cluster. Multi-body properties such as viscosity are well predicted experimentally by the 2-body Kirkwood-Buff quantity, G22, but not by the second virial coefficient, B22, and well-predicted theoretically from the Wertheim protein-protein sticking energy. Weakly interacting antibodies are rate-limited by nucleation; strongly interacting ones by propagation. This approach gives a way to relate micro to macro properties of solutions of associating proteins.


Assuntos
Anticorpos Monoclonais , Anticorpos Monoclonais/química , Humanos , Soluções , Viscosidade
19.
Biochem Biophys Res Commun ; 440(2): 271-6, 2013 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-24055706

RESUMO

Vesicular stomatitis virus (VSV) is a prototypic negative sense single-stranded RNA virus. The bullet-shape appearance of the virion results from tightly wound helical turns of the nucleoprotein encapsidated RNA template (N-RNA) around a central cavity. Transcription and replication require polymerase complexes, which include a catalytic subunit L and a template-binding subunit P. L and P are inferred to be in the cavity, however lacking direct observation, their exact position has remained unclear. Using super-resolution fluorescence imaging and atomic force microscopy (AFM) on single VSV virions, we show that L and P are packaged asymmetrically towards the blunt end of the virus. The number of L and P proteins varies between individual virions and they occupy 57 ± 12 nm of the 150 nm central cavity of the virus. Our finding positions the polymerases at the opposite end of the genome with respect to the only transcriptional promoter.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Vírus da Estomatite Vesicular Indiana/genética , Proteínas Virais/metabolismo , Montagem de Vírus/fisiologia , Microscopia de Força Atômica , Microscopia de Fluorescência , RNA Viral/genética , Vírus da Estomatite Vesicular Indiana/ultraestrutura
20.
J Biomed Mater Res B Appl Biomater ; 111(4): 795-804, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36382676

RESUMO

Recent studies have highlighted the development prospects of magnetic hyperthermia in cancer therapy. A few studies on the application of Fe3 O4 nanospheres for the magnetic hyperthermia of gynecological malignancies have achieved certain efficacy, but there was no visible progress currently. In this work, Fe3 O4 nanospheres modified with polyetherimide (PEI) and folic acid (FA) were synthesized using a hydrothermal method for possible utility in biocompatible and active tumor-targeting magnetic induction hyperthermia. The PEI- and FA-coated Fe3 O4 nanospheres showed high crystallinity, well-dispersed spherical structures and ideal Ms value. As a result, the designed Fe3 O4 @ PEI@FA nanospheres achieved higher specific absorption rate (SAR) values at 360 kHz and 308 Oe, as well as excellent biocompatibility in Hela, SKOV3, HEC-1-A and NIH3T3 cells. These nanospheres can be used as an optimal heating agent for the magnetic hyperthermia treatment of gynecological cancers.


Assuntos
Hipertermia Induzida , Nanosferas , Animais , Camundongos , Humanos , Ácido Fólico/farmacologia , Células NIH 3T3 , Hipertermia Induzida/métodos , Fenômenos Magnéticos
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