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1.
Materials (Basel) ; 17(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38541481

RESUMO

In hydroforming of parallel double-branch tubes, the material entering the branch zone is obstructed by material accumulation in the main tubes and corners, which decreases the branch height. A tube hydroforming approach is combined with pre-forming and crushing (THPC) to mitigate this problem. A larger diameter tube blank is flattened for pre-forming and then subjected to radial compression for crushing. In the next step, hydroforming forms the parallel double-branch tubes. Experiments and numerical simulations are then carried out to analyze the effect of traditional tube hydroforming (TTH) and the proposed THPC process on the formability of parallel double-branch tubes. The results show that for tubes obtained via THPC, the tube burst pressure increases by 27.5% and the branch height increases 2.37-fold compared to TTH. Additionally, the flattening, pre-forming, and crushing stages cause work hardening of the tube when using the TPHC process. Flattened tubes undergo radial compression to improve the material flowing into the branch tube. The formability of parallel double-branched tubes can be improved by using the TPHC process. Consequently, tube hydroforming, combined with pre-forming and crushing, has been confirmed as a feasible forming process for fabricating parallel double-branch tubes.

2.
Small ; : e2311218, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38533979

RESUMO

MXene's configuration, whether it is aggregated or dispersed in a monolayer, determines the specific application areas and even greatly influences the intrinsic properties of MXene. However, how to desirably control MXene's configuration is challenging. Here, a simple, additive-free, chemical reaction-free, and scalable strategy to optionally and reversibly regulate MXene's ordered stacking and delamination of MXene aggregates (AM) is reported. Just by controlled freezing of MXene aqueous dispersions, the aggregation percentage, delamination percentage, and interlayer spacing of AM can be finely tuned. Experimental results reveal that the freezing-induced aggregation and delamination effects can be explained by the squeezing action of growing ice grains on the MXene excluded/concentrated between ice grains and the expanding action caused by the ice formation between AM lamellae, respectively. The dominance between them depends on the freezing parameter-influenced ice nucleation sites, numbers, and ice grain sizes. This work not only contributes to the preparation, storage, and practical applications of MXene, but also opens a new and green avenue for controlling materials' assembly structures.

3.
J Environ Manage ; 356: 120651, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38531135

RESUMO

Traditional manufacturing industry is in the early stages of transition to low-carbon innovative production, and is in urgent need of a low-carbon innovation system to achieve the goal of carbon neutrality. In order to realize the effective supervision of enterprise carbon emissions, this paper constructs a tripartite evolutionary game model among the corporate, government and public from the perspective of dynamic subsidies and taxes. The main results are as follows. First, the increase in government subsidies to a certain extent will help encourage companies to choose low-carbon innovative production strategies, but more subsidies are not always better. Excessive subsidies will increase the cost of government regulation and reduce the probability of government regulation. Second, the tripartite evolutionary game system does not converge under the static subsidies and taxes mechanism. But the system could quickly converges to the stable condition under dynamic subsidies and taxes. The stable point is the situation of corporate low-carbon innovation, government regulation, and public supervision. Third, the public intervention and supervision can effectively prevent the phenomenon of government misconduct and enterprises over-emission production. And the influence of public reward and punishment is more effective for the government than for enterprises.


Assuntos
Carbono , Impostos , Governo , Regulamentação Governamental , Indústria Manufatureira , China
4.
STAR Protoc ; 4(2): 102160, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36924506

RESUMO

The development of biocompatible ice-controlling materials for non-vitreous cryopreservation of cells is of great importance to the field of biomedicine. Here, we present a protocol to use fulvic acid (FA) for efficient non-vitreous cryopreservation of red blood cells (RBCs) that both promotes the melting of ice crystals and retards their growth/recrystallization. We describe steps for FA fractionation and performing tests for ice recrystallization and ice freezing/thawing. We then detail the freezing/thawing of RBCs, recovering RBCs, and testing their viability. For complete details on the use and execution of this protocol, please refer to Bai et al. (2022).1.

5.
iScience ; 25(6): 104423, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35663038

RESUMO

The exploitation of biocompatible ice-control materials especially the small molecules for non-vitreous cryopreservation remains challenging. Here, we report a small molecule of fulvic acid (FA) with strong hydration ability, which enables non-vitreous cellular cryopreservation by reducing ice growth during freezing and reducing ice recrystallization/promoting ice melting during thawing. Without adding any other cryoprotectants, FA can enhance the recovery of sheep red blood cells (RBCs) by three times as compared with a commercial cryoprotectant (hydroxyethyl starch) under a stringent test condition. Investigation of water mobility reveals that the ice-control properties of FA can be ascribed to its strong bondage to water molecules. Furthermore, we found that FA can be absorbed by RBCs and mainly locates on membranes, suggesting the possible contribution of FA to cell protection through stabilizing membranes. This work bespeaks a bright future for small-molecule cryoprotectants in non-vitreous cryopreservation application.

6.
Cell Cycle ; 20(23): 2531-2546, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34724861

RESUMO

Exosomes mediate the interaction between cancer cells and their microenvironment, and play a key role in tumor development. Although exosomes can package lncRNAs to mediate extracellular communication, the role of exosomal lncRNA AY927529 in prostate cancer (PCa) remains unclear. Exosomes were extracted from normal human prostatic epithelial cell lines (BPH-1 and RWPE-1) and PCa cell lines (VCaP and LNCaP, DU145, PC3) by ultrahigh speed centrifugation. Results of Western blot indicated that Alix, HSC70 and TSGl01 protein levels were upregulated in exosomes derived from PCa cells. LncAY927529 level was upregulated in PCa cells and exosomes derived from PCa patient serum and human PCa cells. CCK-8, Transwell and Flow cytometry assays demonstrated that bone marrow stromal cell line (ST2) conditioned medium (ST2-CM), treated with exosomes derived from PCa cells with high lncAY927529 level, promoted proliferation and invasion of PC3 and DU145 cells, and inhibited cell apoptosis. RT-qPCR assay indicated that lncAY927529 level was downregulated in PC3 and DU145 cells, exosomes derived from PCa cells (PCa-Exo) and ST2-CM treated with PCa-Exo with low expression of lncAY927529, and overexpression of lncAY927529 had the opposite results. In addition, Western blot assay showed that the autophagy related protein LC3II level was increased in ST2 cells treated with exosomes derived from DU145 cells with high expression of lncAY927529, and LC3I protein level was decreased. CXCL14 acted as a RNA-binding protein of lncAY927529, and exosome-mediated lncAY927529 positively regulated CXCL14 levels in ST2 cells. In general, exosome-mediated lncAY927529 could promote PCa cell proliferation and invasion by regulating bone microenvironment, suggesting that exosomal lncAY927529 may be a potential molecular diagnostic marker of PCa.


Assuntos
Exossomos , MicroRNAs , Hiperplasia Prostática , Neoplasias da Próstata , RNA Longo não Codificante , Osso e Ossos/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Exossomos/genética , Exossomos/metabolismo , Humanos , Masculino , MicroRNAs/genética , Próstata , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Microambiente Tumoral/genética
7.
BMC Cancer ; 21(1): 1022, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525951

RESUMO

BACKGROUND: Eukaryotic translation initiation factors (eIFs) are the key factors to synthesize translation initiation complexes during the synthesis of eukaryotic proteins. Besides, eIFs are especially important in regulating the immune function of tumor cells. However, the effect mechanism of eIFs in prostate cancer remains to be studied, which is precisely the purpose of this study. METHODS: In this study, three groups of prostate cancer cells were investigated. One group had its eIF5B gene knocked down; another group had its Programmed death 1 (PD-L1) overexpressed; the final group had its Wild-type p53-induced gene 1 (Wig1) overexpressed. Genetic alterations of the cancer cells were performed by plasmid transfection. The expression of PD-L1 mRNA was detected by quantitative real-time PCR (qRT-PCR), and the expressions of PD-L1 and eIF5B proteins were observed by western blot assays. Cell Counting Kit-8 (CCK-8), flow cytometry, Transwell and Transwell martrigel were used to investigated cell proliferation, apoptosis, migration and invasion, respectively. The effect of peripheral blood mononuclear cells (PBMCs) on tumor cells was observed, and the interaction between eIF5B and Wig1 was revealed by co-immunoprecipitation (CoIP) assay. Finally, the effects of interference with eIF5B expression on the growth, morphology, and immunity of the tumor, as well as PD-L1 expression in the tumor, were verified by tumor xenograft assays in vivo. RESULTS: Compared with normal prostate epithelial cells, prostate cancer cells revealed higher expressions of eIF5B and PD-L1 interference with eIF-5B expression can inhibit the proliferation, migration, invasion and PD-L1 expression of prostate cancer cells. Meanwhile, the cancer cell group with interference with eIF5B expression also demonstrated greater, apoptosis and higher vulnerability to PBMCs. CoIP assays showed that Wig1 could bind to eIF5B in prostate cancer cells, and its overexpression can inhibit the proliferation, migration, invasion and PD-L1 expression of cancer cells while promoting apoptosis. Moreover, interference with eIF5B expression can inhibit tumor growth, destroy tumor morphology, and suppress the proliferation of tumor cells. CONCLUSION: eIF5B can promote the expression of PD-L1 by interacting with Wig1. Besides, interference with eIF5B expression can inhibit the proliferation, migration, invasion and immunosuppressive response of prostate cancer cells. This study proposes a new target, eIF5B, for immunotherapy of prostate cancer.


Assuntos
Antígeno B7-H1/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Apoptose/genética , Antígeno B7-H1/imunologia , Biomarcadores Tumorais/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Fatores de Iniciação em Eucariotos/genética , Citometria de Fluxo , Inativação Gênica , Genes p53/fisiologia , Humanos , Imunoprecipitação , L-Lactato Desidrogenase/metabolismo , Leucócitos Mononucleares/imunologia , Linfócitos do Interstício Tumoral , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica/genética , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Transfecção/métodos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
BMC Cancer ; 20(1): 555, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539763

RESUMO

BACKGROUND: Prostate cancer (PC), a common malignant tumor, is the second-leading cause of cancer death among American men. Its successful treatment greatly relies on the early diagnose. Engrailed-2 (EN2) has been confirmed being existed with a high level in the urine of PC patients. In this study, to explore the application of EN2 in PC, we detected the immunohistochemical staining difference and EN2 expression level between benign prostatic hyperplasia (BPH) and PC. METHODS: We developed a monoclonal antibody against the helix 3 in EN2 and confirmed its specificity with Western blotting (WB) and immunofluorescence detecting the subcellular localization of endogenous and exogenous EN2 in three PC cell lines (LNCap, PC3, and DU145). We conducted immunohistochemical staining using this homemade antibody, and RT-PCR to detect the expression of EN2 in 25 PC and 25 BPH cases, and analyzed the correlation of EN2 expression and PC clinical staging. RESULTS: The results of WB and immunofluorescence showed our homemade EN2 monoclonal antibody could specifically bind endogenous and exogenous EN2 protein in three different PC cell lines. Endogenous EN2 was generally expressed in the cytoplasm and exogenous EN2 mostly existed in the nucleus of these cell lines. Immunohistochemical staining in PC had extremely stronger signals than that in BPH, suggesting a higher EN2 expression level in PC, which was confirmed by RT-PCR. Interestingly, the stained areas in BPH tissues were mainly in nucleus and cytoplasm, while in PC tissues were mainly on cytomembrane. Moreover, the expression level of EN2 was positively correlated with the PC clinical staging. CONCLUSION: Using our homemade EN2 antibody, we have found different staining patterns and expression level of EN2 in BPH and PC,which may be helpful to predict prostatic disease progression.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Homeodomínio/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Próstata/patologia , Hiperplasia Prostática/patologia , Neoplasias da Próstata/diagnóstico , Idoso , Biomarcadores Tumorais/análise , Linhagem Celular Tumoral , Progressão da Doença , Perfilação da Expressão Gênica , Proteínas de Homeodomínio/análise , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/análise , Prognóstico , Neoplasias da Próstata/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
J Dent ; 40(2): 163-71, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22198196

RESUMO

OBJECTIVE: This study evaluated the effects of exogenous collagenase and two collagenase inhibitors on the variation in microstructure of human collagen fibrils. METHODS: Dentine specimens which were sectioned from 6 freshly extracted human caries-free third molars were wet polished. Each specimen was divided into 4 parts which were treated as experimental groups (group 1, group 2, group 3) and the control group, respectively. All the specimens were etched and further treated with NaClOaq. Subsequently, the topography of each specimen was observed using atomic force microscopy (AFM) in tapping mode in air. Group 1 was then treated with a solution of collagenase II. Group 2 was treated with a solution of collagenase II and chlorhexidine (saturated solution). Group 3 was treated with a solution of collagenase II and captopril (0.3%). The control group was treated with a buffer solution. After 3h and 6h of treatment, the topography of the collagen fibrils was measured with AFM in air, respectively. RESULTS: AFM images of the dentine collagen fibrils were obtained after treatment with NaOClaq. Following further treatment with collagenase II, the topography of the collagen fibrils changed. Most reticular collagen fibrils disappeared after 6h. After treatment with collagenase II in the presence of chlorhexidine or captopril for 3h and 6h, the morphology of the collagen fibres was not changed obviously. CONCLUSIONS: Exogenous collagenase II effectively degraded human dentine collagen fibrils, and its collagenolytic activity was inhibited by the exogenous collagenase inhibitors, chlorhexidine and captopril.


Assuntos
Colágeno/efeitos dos fármacos , Colagenases/farmacologia , Dentina/efeitos dos fármacos , Condicionamento Ácido do Dente/métodos , Adulto , Captopril/farmacologia , Clorexidina/farmacologia , Colágeno/ultraestrutura , Dentina/ultraestrutura , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Metaloproteinase 8 da Matriz/farmacologia , Inibidores de Metaloproteinases de Matriz , Microscopia de Força Atômica , Hipoclorito de Sódio/química , Fatores de Tempo , Adulto Jovem
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