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1.
Nature ; 590(7845): 262-267, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33568822

RESUMO

Steels with sub-micrometre grain sizes usually possess high toughness and strength, which makes them promising for lightweighting technologies and energy-saving strategies. So far, the industrial fabrication of ultrafine-grained (UFG) alloys, which generally relies on the manipulation of diffusional phase transformation, has been limited to steels with austenite-to-ferrite transformation1-3. Moreover, the limited work hardening and uniform elongation of these UFG steels1,4,5 hinder their widespread application. Here we report the facile mass production of UFG structures in a typical Fe-22Mn-0.6C twinning-induced plasticity steel by minor Cu alloying and manipulation of the recrystallization process through the intragranular nanoprecipitation (within 30 seconds) of a coherent disordered Cu-rich phase. The rapid and copious nanoprecipitation not only prevents the growth of the freshly recrystallized sub-micrometre grains but also enhances the thermal stability of the obtained UFG structure through the Zener pinning mechanism6. Moreover, owing to their full coherency and disordered nature, the precipitates exhibit weak interactions with dislocations under loading. This approach enables the preparation of a fully recrystallized UFG structure with a grain size of 800 ± 400 nanometres without the introduction of detrimental lattice defects such as brittle particles and segregated boundaries. Compared with the steel to which no Cu was added, the yield strength of the UFG structure was doubled to around 710 megapascals, with a uniform ductility of 45 per cent and a tensile strength of around 2,000 megapascals. This grain-refinement concept should be extendable to other alloy systems, and the manufacturing processes can be readily applied to existing industrial production lines.

2.
J Hematol Oncol ; 17(1): 46, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38886806

RESUMO

The Wnt/ß-catenin signaling pathway plays a crucial role in various physiological processes, encompassing development, tissue homeostasis, and cell proliferation. Under normal physiological conditions, the Wnt/ß-catenin signaling pathway is meticulously regulated. However, aberrant activation of this pathway and downstream target genes can occur due to mutations in key components of the Wnt/ß-catenin pathway, epigenetic modifications, and crosstalk with other signaling pathways. Consequently, these dysregulations contribute significantly to tumor initiation and progression. Therapies targeting the Wnt/ß-catenin signaling transduction have exhibited promising prospects and potential for tumor treatment. An increasing number of medications targeting this pathway are continuously being developed and validated. This comprehensive review aims to summarize the latest advances in our understanding of the role played by the Wnt/ß-catenin signaling pathway in carcinogenesis and targeted therapy, providing valuable insights into acknowledging current opportunities and challenges associated with targeting this signaling pathway in cancer research and treatment.


Assuntos
Carcinogênese , Neoplasias , Via de Sinalização Wnt , Humanos , Via de Sinalização Wnt/efeitos dos fármacos , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Carcinogênese/genética , Carcinogênese/metabolismo , Animais , beta Catenina/metabolismo , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Terapia de Alvo Molecular/métodos
3.
Genes Dis ; 11(4): 101066, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38550714

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has decreased the efficacy of SARS-CoV-2 vaccines in containing coronavirus disease 2019 (COVID-19) over time, and booster vaccination strategies are urgently necessitated to achieve sufficient protection. Intranasal immunization can improve mucosal immunity, offering protection against the infection and sustaining the spread of SARS-CoV-2. In this study, an intranasal booster of the RBD-HR vaccine after two doses of the mRNA vaccine significantly increased the levels of specific binding antibodies in serum, nasal lavage fluid, and bronchoalveolar lavage fluid compared with only two doses of mRNA vaccine. After intranasal boosting with the RBD-HR vaccine, the levels of serum neutralizing antibodies against prototype and variant strains of SARS-CoV-2 pseudoviruses were markedly higher than those in mice receiving mRNA vaccine alone, and intranasal boosting with the RBD-HR vaccine also inhibited the binding of RBD to hACE2 receptors. Furthermore, the heterologous intranasal immunization regimen promoted extensive memory T cell responses and activated CD103+ dendritic cells in the respiratory mucosa, and potently enhanced the formation of T follicular helper cells and germinal center B cells in vital immune organs, including mediastinal lymph nodes, inguinal lymph nodes, and spleen. Collectively, these data infer that heterologous intranasal boosting with the RBD-HR vaccine elicited broad protective immunity against SARS-CoV-2 both locally and systemically.

4.
MedComm (2020) ; 5(5): e539, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38680520

RESUMO

Urgent research into innovative severe acute respiratory coronavirus-2 (SARS-CoV-2) vaccines that may successfully prevent various emerging emerged variants, particularly the Omicron variant and its subvariants, is necessary. Here, we designed a chimeric adenovirus-vectored vaccine named Ad5-Beta/Delta. This vaccine was created by incorporating the receptor-binding domain from the Delta variant, which has the L452R and T478K mutations, into the complete spike protein of the Beta variant. Both intramuscular (IM) and intranasal (IN) vaccination with Ad5-Beta/Deta vaccine induced robust broad-spectrum neutralization against Omicron BA.5-included variants. IN immunization with Ad5-Beta/Delta vaccine exhibited superior mucosal immunity, manifested by higher secretory IgA antibodies and more tissue-resident memory T cells (TRM) in respiratory tract. The combination of IM and IN delivery of the Ad5-Beta/Delta vaccine was capable of synergically eliciting stronger systemic and mucosal immune responses. Furthermore, the Ad5-Beta/Delta vaccination demonstrated more effective boosting implications after two dosages of mRNA or subunit recombinant protein vaccine, indicating its capacity for utilization as a booster shot in the heterologous vaccination. These outcomes quantified Ad5-Beta/Delta vaccine as a favorable vaccine can provide protective immunity versus SARS-CoV-2 pre-Omicron variants of concern and BA.5-included Omicron subvariants.

5.
Materials (Basel) ; 16(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37763380

RESUMO

Quenching and partitioning (Q&P) steel has garnered attention as a promising third-generation automotive steel. While the conventional production (CP) method for Q&P steel involves a significant cumulative cold rolling reduction rate (CRRR) of 60-70%, the thin slab casting and rolling (TSCR) process has emerged as a potential alternative to reduce or eliminate the need for cold rolling, characterized with a streamline production chain, high-energy efficiency, mitigated CO2 emission and economical cost. However, the effect of the CRRR on the microstructure and properties of Q&P steel with an initial ferrite-pearlite microstructure has been overlooked, preventing the extensive application of TSCR in producing Q&P steel. In this work, investigations involving different degrees of CRRRs reveal a direct relationship between increased reduction and decreased yield strength and plasticity. Notably, changes in the microstructure were observed, including reduced size and proportion of martensite blocks, increased ferrite proportion and decreased retained austenite content. The decrease in yield strength was primarily attributed to the increased proportion of the softer ferrite phase, while the reduction in plasticity was primarily linked to the decrease in retained austenite content. This study provides valuable insights for optimizing the TSCR process of Q&P steel, facilitating its wider adoption in the automotive sector.

6.
Front Immunol ; 14: 1156239, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37153576

RESUMO

As an essential micronutrient, manganese plays an important role in the physiological process and immune process. In recent decades, cGAS-STING pathway, which can congenitally recognize exogenous and endogenous DNA for activation, has been widely reported to play critical roles in the innate immunity against some important diseases, such as infections and tumor. Manganese ion (Mn2+) has been recently proved to specifically bind with cGAS and activate cGAS-STING pathway as a potential cGAS agonist, however, is significantly restricted by the low stability of Mn2+ for further medical application. As one of the most stable forms of manganese, manganese dioxide (MnO2) nanomaterials have been reported to show multiple promising functions, such as drug delivery, anti-tumor and anti-infection activities. More importantly, MnO2 nanomaterials are also found to be a potential candidate as cGAS agonist by transforming into Mn2+, which indicates their potential for cGAS-STING regulations in different diseased conditions. In this review, we introduced the methods for the preparation of MnO2 nanomaterials as well as their biological activities. Moreover, we emphatically introduced the cGAS-STING pathway and discussed the detailed mechanisms of MnO2 nanomaterials for cGAS activation by converting into Mn2+. And we also discussed the application of MnO2 nanomaterials for disease treatment by regulating cGAS-STING pathway, which might benefit the future development of novel cGAS-STING targeted treatments based on MnO2 nanoplatforms.


Assuntos
Neoplasias , Transdução de Sinais , Humanos , Manganês , Compostos de Manganês/farmacologia , Óxidos/uso terapêutico , Nucleotidiltransferases/metabolismo , Neoplasias/tratamento farmacológico
7.
Front Immunol ; 14: 1128840, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36926351

RESUMO

Manganese (Mn), a nutrient inorganic trace element, is necessary for a variety of physiological processes of animal body due to their important roles in oxidative regulation effects and other aspects of activities. Moreover, manganese ion (Mn2+) has widely reported to be crucial for the regulations of different immunological responses, thus showing promising application as potential adjuvants and immunotherapeutics. Taking the advantages of Mn-based biological and immunological activities, Manganese dioxide nanoparticles (MnO2 NPs) are a new type of inorganic nanomaterials with numerous advantages, including simple preparation, low cost, environmental friendliness, low toxicity, biodegradable metabolism and high bioavailability. MnO2 NPs, as a kind of drug carrier, have also shown the ability to catalyze hydrogen peroxide (H2O2) to produce oxygen (O2) under acidic conditions, which can enhance the efficacy of radiotherapy, chemotherapy and other therapeutics for tumor treatment by remodeling the tumor microenvironment. More importantly, MnO2 NPs also play important roles in immune regulations both in innate and adaptive immunity. In this review, we summarize the biological activities of Manganese, followed by the introduction for the biological and medical functions and mechanisms of MnO2 NPs. What's more, we emphatically discussed the immunological regulation effects and mechanisms of MnO2 NPs, as well as their potentials to serve as adjuvants and immunomodulators, which might benefit the development of novel vaccines and immunotherapies for more effective disease control.


Assuntos
Nanopartículas , Vacinas , Animais , Compostos de Manganês/farmacologia , Compostos de Manganês/metabolismo , Manganês , Óxidos/farmacologia , Peróxido de Hidrogênio/metabolismo , Nanopartículas/metabolismo , Oxigênio , Imunoterapia
8.
Front Nutr ; 10: 1116051, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36819694

RESUMO

Autophagy, one of the major intracellular degradation systems, plays an important role in maintaining normal cellular physiological functions and protecting organisms from different diseases. Selenium (Se), an essential trace element, is involved in many metabolic regulatory signaling events and plays a key role in human health. In recent years, selenium nanoparticles (Se NPs) have attracted increasing attentions in biomedical field due to their low toxicity, high bioavailability and high bioactivity. Taking the advantage of their advanced biological activities, Se NPs can be used alone as potential therapeutic agents, or combine with other agents and served as carriers for the development of novel therapeutics. More interestingly, Se NPs have been widely reported to affect autophagy signaling, which therefor allow Se NPs to be used as potential therapeutic agents against different diseases. Here, this review suggested the relationships between Se and autophagy, followed by the trends and recent progresses of Se NPs for autophagy regulation in different diseased conditions. More importantly, this work discussed the roles and potential mechanisms of Se NPs in autophagy regulating, which might enhance our understanding about how Se NPs regulate autophagy for potential disease treatment. This work is expected to promote the potential application of Se NPs as novel autophagy regulators, which might benefit the development of novel autophagy associated therapeutics.

9.
J Hematol Oncol ; 15(1): 129, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076302

RESUMO

Epithelial-mesenchymal transition (EMT) is an essential process in normal embryonic development and tissue regeneration. However, aberrant reactivation of EMT is associated with malignant properties of tumor cells during cancer progression and metastasis, including promoted migration and invasiveness, increased tumor stemness, and enhanced resistance to chemotherapy and immunotherapy. EMT is tightly regulated by a complex network which is orchestrated with several intrinsic and extrinsic factors, including multiple transcription factors, post-translational control, epigenetic modifications, and noncoding RNA-mediated regulation. In this review, we described the molecular mechanisms, signaling pathways, and the stages of tumorigenesis involved in the EMT process and discussed the dynamic non-binary process of EMT and its role in tumor metastasis. Finally, we summarized the challenges of chemotherapy and immunotherapy in EMT and proposed strategies for tumor therapy targeting EMT.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias , Transformação Celular Neoplásica , Epigênese Genética , Humanos , Imunoterapia , Metástase Neoplásica , Neoplasias/patologia , Neoplasias/terapia
10.
Pharmaceutics ; 14(11)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36365168

RESUMO

Infectious diseases remain the most serious public health issue, which requires the development of more effective strategies for infectious control. As a kind of ultra-trace element, cobalt is essential to the metabolism of different organisms. In recent decades, nanotechnology has attracted increasing attention worldwide due to its wide application in different areas, including medicine. Based on the important biological roles of cobalt, cobalt nanomaterials have recently been widely developed for their attractive biomedical applications. With advantages such as low costs in preparation, hypotoxicity, photothermal conversion abilities, and high drug loading ability, cobalt nanomaterials have been proven to show promising potential in anticancer and anti-infection treatment. In this review, we summarize the characters of cobalt nanomaterials, followed by the advances in their biological functions and mechanisms. More importantly, we emphatically discuss the potential of cobalt nanomaterials as anti-infectious agents, drug carriers, and immunomodulators for anti-infection treatments, which might be helpful to facilitate progress in future research of anti-infection therapy.

11.
Front Pharmacol ; 12: 518406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33994999

RESUMO

Marsdeniae tenacissimae Caulis is a traditional Chinese medicine, named Tongguanteng (TGT), that is often used for the adjuvant treatment of cancer. In our previous study, we reported that an ethyl acetate extract of TGT had inhibitory effects against adenocarcinoma A549 cells growth. To identify the components of TGT with anti-tumor activity and to elucidate their underlying mechanisms of action, we developed a technique for isolating compounds, which was then followed by cytotoxicity screening, network pharmacology analysis, and cellular and molecular experiments. We isolated a total of 19 compounds from a TGT ethyl acetate extract. Two novel steroidal saponins were assessed using an ultra-performance liquid chromatography-photodiode array coupled with quadrupole time-of-flight mass (UPLC-ESI-Q/TOF-MS). Then, we screened these constituents for anti-cancer activity against non-small cell lung cancer (NSCLC) in vitro and obtained six target compounds. Furthermore, a compound-target-pathway network of these six bioactive ingredients was constructed to elucidate the potential pathways that controlled anticancer effects. Approximately 205 putative targets that were associated with TGT, as well as 270 putative targets that were related to NSCLC, were obtained from online databases and target prediction software. Protein-protein interaction networks for drugs as well as disease putative targets were generated, and 18 candidate targets were detected based on topological features. In addition, pathway enrichment analysis was performed to identify related pathways, including PI3K/AKT, VEGF, and EGFR tyrosine kinase inhibitor resistance, which are all related to metabolic processes and intrinsic apoptotic pathways involving reactive oxygen species (ROS). Then, various cellular experiments were conducted to validate drug-target mechanisms that had been predicted using network pharmacology analysis. The experimental results showed the four C21 steroidal saponins could upregulate Bax and downregulate Bcl-2 expression, thereby changing the mitochondrial membrane potential, producing ROS, and releasing cytochrome C, which finally activated caspase-3, caspase-9, and caspase-8, all of which induced apoptosis in A549 cells. In addition, these components also downregulated the expression of MMP-2 and MMP-9 proteins, further weakening their degradation of extracellular matrix components and type IV collagen, and inhibiting the migration and invasion of A549 cells. Our study elucidated the chemical composition and underlying anti-tumor mechanism of TGT, which may be utilized in the treatment of lung cancer.

12.
Sci Rep ; 8(1): 7512, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29760456

RESUMO

In ß titanium alloys, the ß stabilizers segregate easily and considerable effort has been devoted to alleviate/eliminate the segregation. In this work, instead of addressing the segregation problems, the segregation was utilized to develop a novel microstructure consisting of a nanometre-grained duplex (α+ß) structure and micrometre scale ß phase with superior mechanical properties. An as-cast Ti-9Mo-6W alloy exhibited segregation of Mo and W at the tens of micrometre scale. This was subjected to cold rolling and flash annealing at 820 oC for 2 and 5 mins. The solidification segregation of Mo and W leads to a locally different microstructure after cold rolling (i.e., nanostructured ß phase in the regions rich in Mo and W and plate-like martensite and ß phase in regions relatively poor in Mo and W), which play a decisive role in the formation of the heterogeneous microstructure. Tensile tests showed that this alloy exhibited a superior combination of high yield strength (692 MPa), high tensile strength (1115 MPa), high work hardening rate and large uniform elongation (33.5%). More importantly, the new technique proposed in this work could be potentially applicable to other alloy systems with segregation problems.

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