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1.
Chem Biodivers ; : e202302102, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567653

RESUMO

Rosa laevigata Michx. polysaccharides (RLP) have been demonstrated to possess antioxidant and anti-inflammatory properties. However, the mechanisms and efficacy of these polysaccharide components in preventing ulcerative colitis (UC) remain to be elucidated. The efficacy and mechanisms of RLP were investigated in a study that utilized healthy adult beagles to establish a UC model, considering the similarities in gut microbiota between humans and dogs. In the study, the beagle model induced by sodium dextran sulfate exhibited typical symptoms of ulcerative colitis, such as weight loss and diarrhea. All these symptoms and changes were significantly ameliorated through oral supplementation of RLP. Additionally, microbial community analysis based on the 16S rDNA gene revealed that RLP alleviated UC by increasing the abundance of beneficial bacteria and reducing the abundance of harmful bacteria. In conclusion, our study has provided that RLP effectively alleviated colitis by preserving the intestinal barrier and regulating the gut microbiota composition.

2.
Inorg Chem ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651966

RESUMO

Due to their maximum atomic use of metal sites, single-atom catalysts (SACs) exhibit excellent catalytic activity in a variety of reactions. Although many techniques have been reported for the production of SACs, the construction of single atoms through a convenient strategy is still challenging. Here, we provide a facile method to prepare nickel SACs by utilizing the inherent confined space between the template and silica walls in template-occupied mesoporous silica KIT-6 (TOK). After the introduction of nickel-containing precursors into the inherent confined space of the TOK by solid-phase grinding, Ni SACs can be produced promptly during calcination. Single Ni atoms create a covalent Ni-O-Si structure in the TOK, as indicated by density functional theory (DFT) calculations and experimental data. This synthetic approach is easy to scale up, and 10 g of sample can be effortlessly synthesized using ball milling. The resultant Ni SACs were applied to the oxygen evolution reaction and exhibited higher catalytic activity and stability than the comparative sample synthesized in the absence of confined space.

3.
PLoS One ; 19(4): e0302052, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38603725

RESUMO

The future of communication systems is undergoing a transformative shift towards intelligence, efficiency, and flexibility. Presently, the amalgamation of blockchain technology and the sixth-generation mobile communication network (6G) has garnered significant attention, as their fusion is poised to profoundly impact the digital economy and society at large. However, the convergence of blockchain and 6G networks poses challenges pertaining to security and performance. In this article, we propose an approach based on the design of secure mechanisms and performance optimization to delve into the key issues surrounding the integration of blockchain and 6G networks from both security and performance perspectives. Specifically, we first introduce the application scenarios of 6G networks and blockchain's empowerment of them to highlight the necessity of combining blockchain technology with 6G. Subsequently, in order to ensure the security of communication and data transmission between blockchain and 6G networks, we have investigated the design requirements for security mechanisms. Furthermore, we discuss the efficient realization of the amalgamation between blockchain and 6G networks by proposing a solution based on Directed Acyclic Graph (DAG) for blockchain's asynchronous consensus protocol, alongside optimization strategies for storage and communication to meet the desired characteristics and requirements of 6G networks. Lastly, we provide valuable research directions that serve as references and guidance for the future development of the integration between blockchain and 6G networks.


Assuntos
Blockchain , Consenso , Inteligência , Tecnologia , Segurança Computacional
4.
Int J Biol Macromol ; 264(Pt 2): 130621, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447834

RESUMO

The immune system acts as a vital defense barrier against pathogenic invasions, and its stable operation is crucial for maintaining body health. Nevertheless, various natural or artificial factors can compromise the body's immune function, leading to immunosuppression, which may interfere with the efficacy of vaccination and increase the susceptibility of the body to disease-causing pathogens. In an effort to ensure successful vaccinations and improve overall physical well-being, the search for appropriate immune regulators to enhance immunity is of paramount importance. Lentinan (LNT) has a significant role in immune regulation and vaccine adjuvants. In the present study, we constructed an immunosuppressive model using dexamethasone (DEX) and demonstrated that LNT could significantly improved antibody levels in immunosuppressive mice and stimulated T-lymphocyte proliferation and differentiation in intestinal Peyer's patches. LNT also increased the production of secretory immunoglobulin A (sIgA) in the duodenal fluid, the number of goblet cells, and the proportion of mucin area. Moreover, LNT modulated the intestinal microbiota and increased the production of short-chain fatty acids. Additionally, LNT promoted the proliferation, differentiation, and pro-inflammatory cytokines production of DEX-treated splenic T lymphocytes in vitro. Thus, the present study highlights the potential of LNT in reversing immunosuppression and avoiding the failure of vaccination.


Assuntos
Terapia de Imunossupressão , Lentinano , Animais , Camundongos , Lentinano/farmacologia , Tolerância Imunológica , Intestinos , Dexametasona/farmacologia
5.
Plant Signal Behav ; 19(1): 2310963, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38314783

RESUMO

In higher plants, the regulatory roles of cAMP (cyclic adenosine 3',5'-monophosphate) signaling remain elusive until now. Cellular cAMP levels are generally much lower in higher plants than in animals and transiently elevated for triggering downstream signaling events. Moreover, plant adenylate cyclase (AC) activities are found in different moonlighting multifunctional proteins, which may pose additional complications in distinguishing a specific signaling role for cAMP. Here, we have developed rapeseed (Brassica napus L.) transgenic plants that overexpress an inducible plant-origin AC activity for generating high AC levels much like that in animal cells, which served the genetic model disturbing native cAMP signaling as a whole in plants. We found that overexpression of the soluble AC activity had significant impacts on the contents of indole-3-acetic acid (IAA) and stress phytohormones, i.e. jasmonic acid (JA), abscisic acid (ABA), and salicylic acid (SA) in the transgenic plants. Acute induction of the AC activity caused IAA overaccumulation, and upregulation of TAA1 and CYP83B1 in the IAA biosynthesis pathways, but also simultaneously the hyper-induction of PR4 and KIN2 expression indicating activation of JA and ABA signaling pathways. We observed typical overgrowth phenotypes related to IAA excess in the transgenic plants, including significant increases in plant height, internode length, width of leaf blade, petiole length, root length, and fresh shoot biomass, as well as the precocious seed development, as compared to wild-type plants. In addition, we identified a set of 1465 cAMP-responsive genes (CRGs), which are most significantly enriched in plant hormone signal transduction pathway, and function mainly in relevance to hormonal, abiotic and biotic stress responses, as well as growth and development. Collectively, our results support that cAMP elevation impacts phytohormone homeostasis and signaling, and modulates plant growth and development. We proposed that cAMP signaling may be critical in configuring the coordinated regulation of growth and development in higher plants.


Assuntos
Brassica napus , Ciclopentanos , Oxilipinas , Reguladores de Crescimento de Plantas , Animais , Reguladores de Crescimento de Plantas/metabolismo , Brassica napus/genética , Brassica napus/metabolismo , Ácido Abscísico/metabolismo , Proteínas de Plantas/metabolismo , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo
6.
Int J Mol Sci ; 25(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38396810

RESUMO

RLPa-2 (Mw 15.6 kDa) is a polysaccharide isolated from Rosa laevigata Michx. It consists of arabinose (Ara), galactose (Gal), rhamnose (Rha), glucose (Glc), xylose (Xyl), and galacturonic acid (Gal-UA) with a molar ratio of 1.00:0.91:0.39:0.34:0.25:0.20. Structural characterization was performed by methylation and NMR analysis, which indicated that RLPa-2 might comprise →6)-α-D-Galp-(1→, →4)-α-D-GalpA-(1→, α-L-Araf-(1→, →2,4)-α-D-Glcp-(1→, ß-D-Xylp, and α-L-Rhap. In addition, the bioactivity of RLPa-2 was assessed through an in vitro macrophage polarization assay. Compared to positive controls, there was a significant decrease in the expression of M1 macrophage markers (CD80, CD86) and p-STAT3/STAT3 protein. Additionally, there was a down-regulation in the production of pro-inflammatory mediators (NO, IL-6, TNF-α), indicating that M1 macrophage polarization induced with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) stimulation could be inhibited by RLPa-2. These findings demonstrate that the RLPa-2 might be considered as a potential anti-inflammatory drug to reduce inflammation.


Assuntos
Frutas , Rosa , Frutas/química , Rosa/química , Polissacarídeos/química , Macrófagos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/análise
7.
Sci Prog ; 107(1): 368504231215973, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38361484

RESUMO

In high-temperature drilling, especially in high-temperature geothermal drilling, cone bits often experience common and severe tooth loss. This issue significantly reduces the cone bit's service life and has a detrimental impact on drilling efficiency. The quality of the fixed teeth plays a crucial role in the performance of the cone bit. In high-temperature environments, conventional methods fail to meet the requirements for securing the cone bit's teeth. Therefore, to address the tooth loss problem in high-temperature drilling, a new tapered tooth structure is proposed. Laboratory experiments were conducted to secure teeth with varying tapers at both normal and high temperatures. The results revealed that the maximum fastening force increased progressively with the degree of taper, reaching its peak at C50. Compared to conventional cylindrical teeth, the maximum fastening force increased by approximately 88.6%-271.1% at different temperatures. The tapered structure demonstrated superior tooth-fixing strength. The maximum fastening force is the smallest at 300 °C, approximately 23.7%-61.2% lower than at normal temperature. Under the same interference conditions, the maximum fastening force increased with greater taper. With interference values of 0.075, 0.095, and 0.115, the maximum fastening force increased by 48.9%-175.1%, 14%-141.6%, and 53%-271.1%, respectively, when compared to cylindrical teeth with C300, C200, C100, and C50 tapers. The tapered structure exhibited superior tooth-fixing strength and significantly enhanced tooth retention strength at high temperatures.

8.
Inorg Chem ; 63(3): 1607-1612, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38194295

RESUMO

Solid base catalysts are widely used in the chemical industry owing to their advantages of environmental friendliness and easy separation. However, their application is limited by basic site aggregation and poor stability. In this study, we report the preparation of magnesium (Mg) single-atom catalysts with high activity and stability by a sublimation-trapping strategy. The Mg net was sublimated as Mg vapor at 620 °C, subsequently transported through argon, and finally trapped on the defects of nitrogen-doped carbon derived from metal-organic framework ZIF-8, producing Mg1/NC. Because of the atomically dispersed Mg sites, the obtained Mg1/NC exhibits high catalytic activity and stability for Knoevenagel condensation of benzaldehyde with malononitrile, which is a typical base-catalyzed reaction. The Mg1/NC catalyst achieves a high efficiency with a turnover frequency of 49.6 h-1, which is much better than that of the traditional counterpart MgO/NC (7.7 h-1). In particular, the activity of Mg1/NC shows no decrease after five catalytic cycles, while that of MgO/NC declines due to the instability of basic sites.

9.
Ann Med Surg (Lond) ; 86(1): 245-251, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38222740

RESUMO

Introduction and importance: The feasibility of combined tislelizumab with gemcitabine and cisplatin as a neoadjuvant regimen for muscle-invasive bladder cancer (MIBC) remains to be investigated. Case presentation: The neoadjuvant treatment not only shrunk tumours significantly but also lowered their stages from T4bN1M0, T3N0M0, and T3bN0M0 to pT1, pT0 and pTis, respectively. The treatment suppressed tumour cell proliferation and promoted luminal-to-basal transition. Clinical discussion: MIBC is an aggressive bladder cancer with poor prognosis. All three patients with MIBC benefited greatly from the neoadjuvant regimen (tislelizumab + gemcitabine + cisplatin). It appears that the effect of the treatment is independent of the levels of programmed death-ligand 1 nor the subtype of urothelial bladder cancer. Conclusion: Combination of tislelizumab with gemcitabine and cisplatin appeared to be a safe and efficacious neoadjuvant therapy for MIBC.

10.
Ir J Med Sci ; 193(1): 85-93, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37523068

RESUMO

OBJECTIVE: Chaperonin-containing tailless complex polypeptide 1 subunit 6A (CCT6A) involves several solid cancers' development and progression, while its clinical utility in prostate cancer management is rarely revealed. Consequently, the present study intended to investigate the linkage of CCT6A with disease features, treatment information, and prognosis of surgical prostate cancer patients. METHODS: CCT6A in 220 surgical prostate cancer patients was determined via immunohistochemistry. Additionally, survival analyses on data from the public databases were performed to validate the prognostic value of CCT6A further. RESULTS: CCT6A expression was upregulated in tumor tissue than in adjacent tissue (P < 0.001). Increased CCT6A was related to elevated Gleason score (P < 0.001) and pathological T stage (P = 0.029). CCT6A was increased in patients with positive surgical margin status (vs. negative) (P = 0.029) and patients with adjuvant external-beam radiation therapy (vs. no) (P = 0.001). Concerning the prognostic value, high tumor CCT6A was linked with shortened disease-free survival (DFS) (P = 0.009), which was also validated through further Cox's proportional hazard regression model analyses (hazard ratio: 2.695, 95% CI: 1.086-6.683, P = 0.032), whereas CCT6A was not correlated with overall survival (OS) (P > 0.050). Additionally, the Gene Expression Profiling Interactive Analysis database indicated that high tumor CCT6A was related to shortened DFS (P = 0.036), but it was not associated with OS (P > 0.050); meanwhile, the Human Protein Atlas database suggested that high tumor CCT6A was linked with reduced OS (P = 0.048). CONCLUSION: Tumor CCT6A high expression correlates with the elevated Gleason score, pathological T stage, and shortened DFS in surgical prostate cancer patients.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Prognóstico , Neoplasias da Próstata/patologia , Análise de Sobrevida , Intervalo Livre de Doença , Chaperonina com TCP-1/genética , Chaperonina com TCP-1/metabolismo
11.
Biomedicines ; 11(11)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38001988

RESUMO

Polymicrobial mastitis is now becoming very common in dairy animals, resulting in exaggerated resistance to multiple antibiotics. The current study was executed to find drug responses in individual and mixed Culture of Staphylococcus aureus and Escherichia coli isolated from milk samples, as well as to evaluate the antibacterial potential of tungsten oxide nanoparticles. These isolates (alone and in mixed culture) were further processed for their responses to antibiotics using the disc diffusion method. On the other hand, tungsten oxide WO3 (W) nanoparticles coupled with antibiotics (ampicillin, A, and oxytetracycline, O) were prepared through the chemical method and characterized by X-ray diffraction, scanning electron microscopy (SEM), and UV-visible techniques. The preparations consisting of nanoparticles alone (W) and coupled with ampicillin (WA) and oxytetracycline (WO) were tested against individual and mixed Culture through the well diffusion and broth microdilution methods. The findings of the current study showed the highest resistance in E. coli was against penicillin (60%) and ampicillin (50%), while amikacin, erythromycin, ciprofloxacin, and oxytetracycline were the most effective antibiotics. S. aureus showed the highest resistance against penicillin (50%), oxytetracycline (40%), and ciprofloxacin (40%), while, except for ampicillin, the sensitive strains of S. aureus were in the range of 40-60% against the rest of antibiotics. The highest zones of inhibition (ZOI) against mixed Culture were shown by imipenem and ampicillin, whereas the highest percentage decrease in ZOI was noted in cases of ciprofloxacin (-240%) and gentamicin (-119.4%) in comparison to individual Culture of S. aureus and E. coli. It was noteworthy that the increase in ZOI was not more than 38% against mixed Culture as compared to the individual Culture. On the other hand, there was a significant reduction in the minimum inhibitory concentration (MIC) of nanoparticle-coupled antibiotics compared to nanoparticles alone for individual and mixed-culture bacteria, while MICs in the case of mixed Culture remained consistently high throughout the trial. This study therefore concluded that diverse drug resistance was present in both individual and mixed-culture bacteria, whereas the application of tungsten oxide nanoparticle-coupled antibiotics proved to be an effective candidate in reversing the drug resistance in bacterial strains.

12.
Int Immunopharmacol ; 124(Pt B): 111034, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37820423

RESUMO

Osteoarthritis (OA) is a degenerative joint disease characterized by cartilage degradation and inflammation. The molecular mechanisms underlying OA progression remain incompletely understood. In this study, we investigated the role of STEAP3 (Six Transmembrane Epithelial Antigen of the Prostate 3) in the development of OA. Our results demonstrated that STEAP3 was upregulated in OA cartilage tissues and contributes to the progression of the disease. To elucidate the mechanism, we employed transcriptomic and interaction proteomics analysis, and identified dysregulated genes and pathways associated with STEAP3 overexpression. Specifically, we found that STEAP3 interacted with Rab7A, a protein involved in intracellular trafficking and autophagy, and suppressed its activity. In addition, STEAP3 interacted with activated C kinase 1 (RACK1) and enhanced its activity. Furthermore, our data indicated that the suppression of Rab7A activity by STEAP3 promoted the activation of receptor tyrosine kinases (RTKs) and the promoting effects of RACK1 by STEAP3, both of which in turn activated the MAPK and JAK/STAT signaling pathways. In conclusion, our findings highlighted the role of STEAP3 in promoting OA progression. By inhibiting Rab7A activity and promoting RACK1 activity, STEAP3 enhanced inflammation through the activation of RTKs and subsequent activation of the MAPK and JAK/STAT signaling pathways. Targeting STEAP3 may provide a potential therapeutic strategy for the treatment of OA by modulating these interconnected pathways.


Assuntos
Osteoartrite , Transdução de Sinais , Animais , Masculino , Ratos , Cartilagem/metabolismo , Inflamação , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Osteoartrite/genética , Receptores de Quinase C Ativada/genética
13.
Carbohydr Polym ; 322: 121362, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37839834

RESUMO

Walnut green husk polysaccharides (WGP) are isolated from the walnut green husk with a mean molecular weight of 12.77 kDa. The structural characterization revealed by methylation and NMR analysis indicated that WGP might consist of →4-α-D-Galp-(1→, α-D-Galp (1→, and →2)-α-L-Rhap-(1→. Previous studies have been demonstrated that WGP effectively prevented liver injury and modulated gut microbiota in high fructose-treated mice and high fat diet-treated rats. In this study, we found for the first time that WGP presenting outstanding protective effects on liver inflammation and gluconeogenesis dysfunction induced by ochratoxin A (OTA) in mice. Firstly, WGP decreased oxidative stress, down-regulated the expression of inflammatory factors and inhibited the TLR4/p65/IκBα pathway in the liver. Then, WGP reversed OTA-induced lower phosphoenolpyruvate carboxyl kinase (PEPCK), and glucose 6-phosphatase (G6PC) activities in the liver. Furthermore, WGP increased the diversity of gut microbiota and the abundance of beneficial bacteria, especially Lactobacillus and Akkermansia. Importantly, the results of fecal microbiota transplantation (FMT) experiment further confirmed that gut microbiota involved in the protective effects of WGP on liver damage induced by OTA. Our results indicated that the protective effect of WGP on liver inflammation and gluconeogenesis dysfunction caused by OTA may be due to the regulation of gut microbiota.


Assuntos
Microbioma Gastrointestinal , Juglans , Camundongos , Ratos , Animais , Gluconeogênese , Fígado , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo
14.
Dev Neurosci ; : 1-10, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37757768

RESUMO

Glioblastoma (GBM) is the most prevalent and fatal form of brain tumor, which is associated with a poor prognosis. ATP-binding cassette subfamily F member 1 (ABCF1) is an E2 ubiquitin-conjugating enzyme, which is implicated in regulating immune responses and tumorigenesis. Aberrant E3 ubiquitylation has been evidenced in GBM. However, the role of ABCF1 in GBM needs to be further explored. The expression of ABCF1, CXC chemokine ligand 12 (CXCL12), and CXC chemokine receptor 4 (CXCR4) in GBM tissues was examined by the GEPIA tool, real-time PCR and Western blotting. HMC3, U251MG, and LN-229 cells were cultured and transfected with shRNA targeting ABCF1 and ABCF1 plasmids. The proliferative, migrative, and invasive ability of cells was detected. Western blotting was used to detect the levels of phosphorylated phosphatidylinositol 3-kinase (PI3K) and phosphorylated protein kinase B (AKT). We observed that GBM tissues had higher ABCF1, CXCL12, and CXCR4 expression levels. The expression levels of CXCL12 and CXCR4 were enhanced by ABCF1 overexpression, which were significantly reversed by silence of ABCF1 in GBM cells. Silencing ABCF1 or CXCR4 inhibition weakened the capacity of GBM cell growth, migration, and invasion, while ectopic ABCF1 expression or CXCL12 treatment enhanced the cellular function of GBM cells. Furthermore, p-PI3K and p-AKT protein levels were downregulated by ABCF1 knockdown or CXCR4 blockade, which were prompted by ABCF1 overexpression or CXCL12 supplement. The ABCF1-CXCL12-CXCR4 axis was identified as a key player in GBM cell survival and metastasis by activating the PI3K/AKT signaling pathway in GBM cells.

15.
Int J Biol Macromol ; 253(Pt 1): 126629, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37657564

RESUMO

Hydrogel has been proven to have the ability to deliver antigens continuously to achieve slow vaccine delivery, which makes it a promising candidate for an adjuvant delivery platform. Meanwhile, graphene oxide (GO) has garnered significant attention due to its good biosafety, excellent surface area and easy modification. However, GO exists as weak colloidal particles and poses challenges in self-assembling into a hydrogel structure. Here, we propose an innovative strategy involving self-assembling lentinan-functionalized graphene oxide hydrogel ((LNT-GO Gel) by simply mixing lentinan (LNT)-functionalized GO with polyethylene imide (PEI), which can simultaneously encapsulate antigens, achieve long-lasting release of antigens and generate excellent adjuvant activity. The results indicated that the LNT-GO Gel can control the release of OVA at the injection site and confer targeted delivering capacity to lymph nodes. And the date demonstrates that LNT-GO Gel displays favorable safety and biodegradability in vivo. Moreover, LNT-GO Gel can enhance the activation and maturation of dendritic cells (DCs) in lymph node, induce stronger OVA-specific antibody response, and promote spleen T lymphocyte differentiation, which underscores that LNT-GO Gel has ability to generate stronger antigen-specific humoral and cellular immune responses. Collectively, these results demonstrate the adjuvant potential of the lentinan-functionalized graphene oxide hydrogel (LNT-GO Gel) for subunit vaccine.


Assuntos
Hidrogéis , Lentinano , Lentinano/farmacologia , Lentinano/química , Adjuvantes Imunológicos/química , Antígenos , Vacinas de Subunidades
16.
Sci Rep ; 13(1): 14020, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37640785

RESUMO

Since a planar periodic transmission line can suppress drastically the electromagnetic coupling, it would be advantageous to use such a kind of transmission lines in solving the problem of miniaturization of circuit area. By adjusting the lattice constants and geometric parameters of periodic microstrip lines, a time domain characteristic impedance that is the same as that of conventional microstrip lines (CMLs) can be achieved. Such periodic microstrip lines can therefore be used to trick high-speed digital signals, causing a digital signal to misjudge the time domain characteristic impedance of the transmission lines. The theoretical analysis has been verified by our experimental measurement results. Besides, a specific expression for the characteristic impedance of lossless periodic artificial materials is deduced by a circuit model and a standard of misidentification for the characteristic impedance of periodic microstrip lines is given for the digital signals.

17.
Sci Adv ; 9(31): eadf3566, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37531433

RESUMO

For clear cell renal cell carcinoma (ccRCC), lipid deposition plays important roles in the development, metastasis, and drug resistance. However, the molecular mechanisms underlying lipid deposition in ccRCC remain largely unknown. By conducting an unbiased CRISPR-Cas9 screening, we identified the epigenetic regulator plant homeodomain finger protein 8 (PHF8) as an important regulator in ccRCC lipid deposition. Moreover, PHF8 is regulated by von Hippel-Lindau (VHL)/hypoxia-inducible factor (HIF) axis and essential for VHL deficiency-induced lipid deposition. PHF8 transcriptionally up-regulates glutamate-ammonia ligase (GLUL), which promotes the lipid deposition and ccRCC progression. Mechanistically, by forming a complex with c-MYC, PHF8 up-regulates TEA domain transcription factor 1 (TEAD1) in a histone demethylation-dependent manner. Subsequently, TEAD1 up-regulates GLUL transcriptionally. Pharmacological inhibition of GLUL by l-methionine sulfoximine not only repressed ccRCC lipid deposition and tumor growth but also enhanced the anticancer effects of everolimus. Thus, the PHF8-GLUL axis represents a potential therapeutic target for ccRCC treatment.


Assuntos
Carcinoma de Células Renais , Glutamato-Amônia Ligase , Histona Desmetilases , Neoplasias Renais , Fatores de Transcrição , Humanos , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Histona Desmetilases/metabolismo , Neoplasias Renais/metabolismo , Lipídeos , Processamento de Proteína Pós-Traducional , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Glutamato-Amônia Ligase/metabolismo
19.
Int Immunopharmacol ; 122: 110566, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37418985

RESUMO

Osteoarthritis is a prevalent joint disease that significantly affects the daily life of the elderly and is one of the primary causes of disability in this population. This study aims to evaluate the potential pro-inflammatory effects and molecular mechanism of Mesenchymal stem cells-derived exosomes (MSC-Exos) in Osteoarthritis. Bilateral ovariectomy was carried out to induce osteoporosis under anesthesia for the mice. MC3T3-E1 cells were induced for 14 days.HE staining, Safranin O staining and Biomechanical parameter analysis were used in this experiment. MSC-Exos improved osteoarthritis in a mouse model by reducing inflammation levels, preventing ferroptosis, and inducing expression of GOT1/CCR2 to regulate ferroptosis. MSC-Exos also promoted cell growth and osteogenic differentiation of bone cells in an in vitro model. Inhibition of GOT1 reduced the effects of MSC-Exos on cell growth and osteogenic differentiation in an osteoarthritis model. MSC-Exos induce Nrf2/HO-1 expression through the GOT1/CCR2 signaling pathway, resulting in the reduction of Ferroptosis. However, inhibition of Nrf2 reduces the effectiveness of MSC-Exos in treating Osteoarthritis.The results of this study suggest that the GOT1/CCR2/Nrf2/HO-1 signaling pathway plays a crucial role in MSC-Exos-mediated reduction of Ferroptosis in macrophages during Osteoarthritis. These findings may provide a potential therapeutic approach for Osteoarthritis and other orthopedic conditions.


Assuntos
Exossomos , Ferroptose , Células-Tronco Mesenquimais , Osteoartrite , Feminino , Camundongos , Animais , Exossomos/metabolismo , Osteogênese , Fator 2 Relacionado a NF-E2/metabolismo , Osteoartrite/terapia , Osteoartrite/metabolismo , Cartilagem , Células-Tronco Mesenquimais/metabolismo
20.
Int Immunopharmacol ; 122: 110570, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37390649

RESUMO

Rheumatoid arthritis (RA) is a common autoimmune disease with a global incidence of approximately 1%. Its complex pathogenesis makes the development of RA-related therapeutics very difficult. Existing drugs for RA have many side effects and are prone to drug resistance. One potential target for RA drugs includes C-Cchemokinereceptortype2 (CCR2), which belongs to the G protein-coupled receptor family. A series of RA drugs targeting CCR2 have been developed; however, the pre-clinical and clinical research results for CCR2 antagonists are inconsistent. We found that CCR2 was also expressed in primary Fibroblast-like synoviocyte (FLS) from patients with RA. CCR2 antagonists can inhibit inflammatory cytokines and matrix metalloproteinases released by RA-FLS but do not affect the proliferation and migration ability of RA-FLS. In addition, CCR2 antagonist-treated RA-FLS indirectly repressed macrophage-mediated inflammation and rescued the viability of chondrocytes. Finally, a CCR2 antagonist ameliorated the collagen-induced arthritic (CIA). CCR2 antagonists may exert anti-inflammatory effects on RA-FLS by inhibiting the JAK-STAT pathway. In summary, a CCR2 antagonist can exert anti-inflammatory effects by acting on RA-FLS. This study provides a new experimental basis for the use of CCR2 antagonists in the development of RA drugs.


Assuntos
Artrite Reumatoide , Sinoviócitos , Humanos , Janus Quinases/metabolismo , Transdução de Sinais , Proliferação de Células , Fatores de Transcrição STAT/metabolismo , Artrite Reumatoide/metabolismo , Inflamação/metabolismo , Anti-Inflamatórios/uso terapêutico , Fibroblastos/metabolismo , Membrana Sinovial/patologia , Células Cultivadas , Receptores CCR2/metabolismo
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