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The development of nanomaterials for energy storage and conversion has always been important. Layered double hydroxide (LDH) is a promising material due to its high capacity, tunable composition and easy synthesis. In this work, the morphology of NiCo-LDH is tuned with surfactants including sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB), and investigated the correlation between morphology and electrochemical properties. NiCo-LDH-SDS with a layered structure exhibited a specific capacitance of 1004 C g-1 at 1 A g-1, which is higher than that of the needle-like NiCo-LDH-CTAB (678 C g-1) and the rod-like NiCo-LDH (279 C g-1). Meanwhile, NiCo-LDH-SDS and NiCo-LDH-CTAB showed a reduction of 36 and 19 mV, respectively, in their overpotentials at 10 mA cm-2 compared to NiCo-LDH. Contact angle and adhesive force measurements proved the influence of morphology on the interfacial properties that layered structure is favorable for the timely detachment of the bubbles. Therefore, rational morphology regulation of LDH can effectively alter the gas-liquid-solid interface and thereby accelerate the reaction kinetics. The connections between morphologies, bubbles releasing and electrochemical performance are well established in this work, which can be applied in the investigation of nanomaterials for energy-related activities, especially the ones concerning bubbles releasing processes.
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BACKGROUND: The accuracy of traditional knee MR imaging in diagnosing anterior cruciate ligament tears, especially partial tears, is relatively low, which may lead to misdiagnosis and missed diagnosis. This study aimed to assess the diagnostic performance of a novel imaging method, high-resolution oblique coronal MRI at an optimal flexed-knee Angle, for ACL tears. METHODS: 50 healthy volunteers were scanned with a scan-assisted device for the optimal flexion angle of ACL. For 92 knee trauma patients selected strictly according to inclusion and exclusion criteria, conventional extended-knee scans (control group) and high-resolution oblique coronal scans based on the optimal flexed-knee angle (experimental group) were conducted. Two observers rated ACL visibility blindly on a 5-point scale. Arthroscopy-defined outcomes determined diagnostic metrics for each method and sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated. RESULTS: The average optimal flexion angle for healthy volunteers was approximately 30° (30.3° ± 5.0°). Imaging demonstrated complete visualization of the ACL in 96.7% of images in the experimental group versus 12.0% in the control group. The diagnostic indicators of the experimental group surpassed those of the control group: sensitivity (94.9% vs. 76.3%), specificity (97.0% vs. 81.8%), positive predictive value (98.2% vs. 88.2%), negative predictive value(91.4% vs. 65.9%), and accuracy (95.7% vs. 78.3%). ROC analysis indicated superior diagnostic performance in the experimental group, with an AUC of 0.945 compared with 0.776 for the control group (p < 0.0001). CONCLUSIONS: High-resolution oblique coronal imaging at the optimal 30° flexed-knee angle improved ACL visualization and diagnostic performance compared with conventional techniques.
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Lesões do Ligamento Cruzado Anterior , Imageamento por Ressonância Magnética , Humanos , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Feminino , Masculino , Adulto , Adulto Jovem , Pessoa de Meia-Idade , Articulação do Joelho/diagnóstico por imagem , Adolescente , Artroscopia/métodosRESUMO
Objective: To develop a model that integrates radiomics features and clinical factors to predict upper gastrointestinal bleeding (UGIB) in patients with decompensated cirrhosis. Methods: 104 decompensated cirrhosis patients with UGIB and 104 decompensated cirrhosis patients without UGIB were randomized according to a 7:3 ratio into a training cohort (n = 145) and a validation cohort (n = 63). Radiomics features of the abdominal skeletal muscle area (SMA) were extracted from the cross-sectional image at the largest level of the third lumbar vertebrae (L3) on the abdominal unenhanced multi-detector computer tomography (MDCT) images. Clinical-radiomics nomogram were constructed by combining a radiomics signature (Rad score) with clinical independent risk factors associated with UGIB. Nomogram performance was evaluated in calibration, discrimination, and clinical utility. Results: The radiomics signature was built using 11 features. Plasma prothrombin time (PT), sarcopenia, and Rad score were independent predictors of the risk of UGIB in patients with decompensated cirrhosis. The clinical-radiomics nomogram performed well in both the training cohort (AUC, 0.902; 95% CI, 0.850-0.954) and the validation cohort (AUC, 0.858; 95% CI, 0.762-0.953) compared with the clinical factor model and the radiomics model and displayed excellent calibration in the training cohort. Decision curve analysis (DCA) demonstrated that the predictive efficacy of the clinical-radiomics nomogram model was superior to that of the clinical and radiomics model. Conclusion: Clinical-radiomics nomogram that combines clinical factors and radiomics features has demonstrated favorable predictive effects in predicting the occurrence of UGIB in patients with decompensated cirrhosis. This helps in early diagnosis and treatment of the disease, warranting further exploration and research.
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The demand for vaccines, particularly those prepared from non-conventional sources, is rising due to the emergence of drug resistance around the globe. Probiotic-based vaccines are a wise example of such vaccines which represent new horizons in the field of vaccinology in providing an enhanced and diversified immune response. The justification for incorporating probiotics into vaccines lies in the fact that that they hold the capacity to regulate immune function directly or indirectly by influencing the gastrointestinal microbiota and related pathways. Several animal-model-based studies have also highlighted the efficacy of these vaccines. The aim of this review is to collect and summarize the trends in the recent scientific literature regarding the role of probiotics in vaccines and vaccinology, along with their impact on target populations.
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Micro- and nanoparticles delivery systems have been widely studied as vaccine adjuvants to enhance immunogenicity and sustain long-term immune responses. Polygonatum sibiricum polysaccharide (PSP) has been widely studied as an immunoregulator in improving immune responses. In this study, we synthesized and characterized cationic modified calcium carbonate (CaCO3) microparticles loaded with PSP (PEI-PSP-CaCO3, CTAB-PSP-CaCO3), studied the immune responses elicited by PEI-PSP-CaCO3 and CTAB-PSP-CaCO3 carrying ovalbumin (OVA). Our results demonstrated that PEI-PSP-CaCO3 significantly enhanced the secretion of IgG and cytokines (IL-4, IL-6, IFN-γ, and TNF-α) in vaccinated mice. Additionally, PEI-PSP-CaCO3 induced the activation of dendritic cells (DCs), T cells, and germinal center (GC) B cells in draining lymph nodes (dLNs). It also enhanced lymphocyte proliferation, increased the ratio of CD4+/CD8+ T cells, and elevated the frequency of CD3+ CD69+ T cells in spleen lymphocytes. Therefore, PEI-PSP-CaCO3 microparticles induced a stronger cellular and humoral immune response and could be potentially useful as a vaccine delivery and adjuvant system.
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Carbonato de Cálcio , Células Dendríticas , Polygonatum , Polissacarídeos , Animais , Camundongos , Carbonato de Cálcio/química , Polygonatum/química , Polissacarídeos/química , Células Dendríticas/imunologia , Células Dendríticas/efeitos dos fármacos , Feminino , Adjuvantes de Vacinas/química , Ovalbumina/imunologia , Ovalbumina/administração & dosagem , Citocinas/metabolismo , Camundongos Endogâmicos BALB C , Adjuvantes Imunológicos/química , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Nanopartículas/químicaRESUMO
Metastasis is the primary culprit behind cancer-related fatalities in multiple cancer types, including prostate cancer. Despite great advances, the precise mechanisms underlying prostate cancer metastasis are far from complete. By using a transgenic mouse prostate cancer model (TRAMP) with and without Phf8 knockout, we have identified a crucial role of PHF8 in prostate cancer metastasis. By complexing with E2F1, PHF8 transcriptionally upregulates SNAI1 in a demethylation-dependent manner. The upregulated SNAI1 subsequently enhances epithelial-to-mesenchymal transition (EMT) and metastasis. Given the role of the abnormally activated PHF8/E2F1-SNAI1 axis in prostate cancer metastasis and poor prognosis, the levels of PHF8 or the activity of this axis could serve as biomarkers for prostate cancer metastasis. Moreover, targeting this axis could become a potential therapeutic strategy for prostate cancer treatment. © 2024 The Pathological Society of Great Britain and Ireland.
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Fator de Transcrição E2F1 , Transição Epitelial-Mesenquimal , Histona Desmetilases , Neoplasias da Próstata , Fatores de Transcrição da Família Snail , Fatores de Transcrição , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/enzimologia , Animais , Fatores de Transcrição da Família Snail/metabolismo , Fatores de Transcrição da Família Snail/genética , Humanos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Fator de Transcrição E2F1/metabolismo , Fator de Transcrição E2F1/genética , Camundongos , Histona Desmetilases/metabolismo , Histona Desmetilases/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Camundongos Knockout , Transdução de Sinais , Metástase Neoplásica , Camundongos Transgênicos , Movimento CelularRESUMO
AIM: To assess the efficacy of positional therapy and oral appliance therapy for the management of positional obstructive sleep apnea. METHODS: We searched PubMed, Web of Science, Cochrane, and SCOPUS for relevant clinical trials. Quality assessment of the included trials was evaluated according to Cochrane's risk of bias tool. We included the following outcomes: The apnea-hypopnea index (AHI), AHI non-supine, AHI supine, sleep efficiency, percentage of supine sleep, Adherence (≥ 4 h/night, ≥ 5 days/week), Oxygen desaturation Index, Arousal Index, Epworth Sleepiness Scale score (ESS), Mean SpO2, and Functional Outcomes of Sleep Questionnaire. RESULTS: The AHI non-supine and the ESS scores were significantly lower in the OAT cohort than in the PT cohort. The PT cohort was associated with a significantly decreased percentage of supine sleep than the OAT cohort (MD= -26.07 [-33.15, -19.00], P = 0.0001). There was no significant variation between PT cohort and OAT cohort regarding total AHI, AHI supine, ODI, sleep efficiency, arousal index, FOSQ, adherence, and mean SpO2. CONCLUSION: Both Positional Therapy and Oral Appliance Therapy effectively addressed Obstructive Sleep Apnea. However, Oral Appliance Therapy exhibited higher efficiency, leading to increased supine sleep percentage and more significant reductions in the Apnea Hypopnea Index during non-supine positions, as well as lower scores on the Epworth Sleepiness Scale.
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Ensaios Clínicos Controlados Aleatórios como Assunto , Apneia Obstrutiva do Sono , Apneia Obstrutiva do Sono/terapia , Humanos , Decúbito Dorsal , Posicionamento do Paciente/métodosRESUMO
BACKGROUND: This study aimed to describe the findings of double superior mesenteric veins (SMVs), a rare anatomical variation, on multidetector computer tomography (MDCT) and magnetic resonance imaging (MRI) images. CASE SUMMARY: We describe the case of a 34-year-old male, who underwent both MDC and MRI examinations of the upper abdomen because of liver cirrhosis. MDCT and MRI angiography images of the upper abdomen revealed an anatomic variation of the superior mesenteric vein (SMV), the double SMVs. CONCLUSION: The double SMVs are a congenital abnormality without potential clinical manifestation. Physicians need to be aware of this anatomical variation during abdominal surgery to avoid iatrogenic injury.
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Avian influenza virus subtype H9N2 has the ability to infect birds and humans, further causing significant losses to the poultry industry and even posing a great threat to human health. Oral vaccine received particular interest for preventing majority infection due to its ability to elicit both mucosal and systemic immune responses, but their development is limited by the bad gastrointestinal (GI) environment, compact epithelium and mucus barrier, and the lack of effective mucosal adjuvants. Herein, we developed the dendritic fibrous nano-silica (DFNS) grafted with Cistanche deserticola polysaccharide (CDP) nanoparticles (CDP-DFNS) as an adjuvant for H9N2 vaccine. Encouragingly, CDP-DFNS facilitated the proliferation of T and B cells, and further induced the activation of T lymphocytes in vitro. Moreover, CDP-DFNS/H9N2 significantly promoted the antigen-specific antibodies levels in serum and intestinal mucosal of chickens, indicating the good ability to elicit both systemic and mucosal immunity. Additional, CDP-DFNS facilitate the activation of CD4 + and CD8 + T cells both in spleen and intestinal mucosal, and the indexes of immune organs. This study suggested that CDP-DFNS may be a new avenue for development of oral vaccine against pathogens that are transmitted via mucosal route.
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Adjuvantes Imunológicos , Galinhas , Imunidade nas Mucosas , Vírus da Influenza A Subtipo H9N2 , Vacinas contra Influenza , Influenza Aviária , Nanopartículas , Polissacarídeos , Dióxido de Silício , Animais , Vírus da Influenza A Subtipo H9N2/imunologia , Vírus da Influenza A Subtipo H9N2/efeitos dos fármacos , Polissacarídeos/administração & dosagem , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/imunologia , Dióxido de Silício/administração & dosagem , Dióxido de Silício/química , Nanopartículas/administração & dosagem , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/imunologia , Imunidade nas Mucosas/efeitos dos fármacos , Influenza Aviária/prevenção & controle , Influenza Aviária/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Administração Oral , Mucosa Intestinal/imunologia , Mucosa Intestinal/efeitos dos fármacos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologiaRESUMO
BACKGROUND: Previous studies have shown that protein kinase MoKin1 played an important role in the growth, conidiation, germination and pathogenicity in rice blast fungus, Magnaporthe oryzae. ΔMokin1 mutant showed significant phenotypic defects and significantly reduced pathogenicity. However, the internal mechanism of how MoKin1 affected the development of physiology and biochemistry remained unclear in M. oryzae. RESULT: This study adopted a multi-omics approach to comprehensively analyze MoKin1 function, and the results showed that MoKin1 affected the cellular response to endoplasmic reticulum stress (ER stress). Proteomic analysis revealed that the downregulated proteins in ΔMokin1 mutant were enriched mainly in the response to ER stress triggered by the unfolded protein. Loss of MoKin1 prevented the ER stress signal from reaching the nucleus. Therefore, the phosphorylation of various proteins regulating the transcription of ER stress-related genes and mRNA translation was significantly downregulated. The insensitivity to ER stress led to metabolic disorders, resulting in a significant shortage of carbohydrates and a low energy supply, which also resulted in severe phenotypic defects in ΔMokin1 mutant. Analysis of MoKin1-interacting proteins indicated that MoKin1 really took participate in the response to ER stress. CONCLUSION: Our results showed the important role of protein kinase MoKin1 in regulating cellular response to ER stress, providing a new research direction to reveal the mechanism of MoKin1 affecting pathogenic formation, and to provide theoretical support for the new biological target sites searching and bio-pesticides developing.
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Estresse do Retículo Endoplasmático , Proteínas Fúngicas , Oryza , Proteômica , Oryza/microbiologia , Oryza/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Doenças das Plantas/microbiologia , Regulação Fúngica da Expressão Gênica , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Mutação , Multiômica , AscomicetosRESUMO
BACKGROUND: The prognostic predictive tool for patients with colorectal liver metastasis (CRLM) is limited and the criteria for administering preoperative neoadjuvant chemotherapy in CRLM patients remain controversial. METHODS: This study enrolled 532 CRLM patients at West China Hospital (WCH) from January 2009 to December 2019. Prognostic factors were identified from the training cohort to construct a WCH-nomogram and evaluating accuracy in the validation cohort. Receiver operating characteristic (ROC) curve analysis was used to compare the prediction accuracy with other existing prediction tools. RESULTS: From the analysis of the training cohort, four independent prognostic risk factors, namely tumor marker score, KRAS mutation, primary lymph node metastasis, and tumor burden score were identified on which a WCH-nomogram was constructed. The C-index of the two cohorts were 0.674 (95% CI: 0.634-0.713) and 0.655 (95% CI: 0.586-0.723), respectively, which was better than the previously reported predication scores (CRS, m-CS and GAME score). ROC curves showed AUCs for predicting 1-, 3-, and 5-year overall survival (OS) of 0.758, 0.709, and 0.717 in the training cohort, and 0.860, 0.669, and 0.692 in the validation cohort, respectively. A cutoff value of 114.5 points was obtained for the WCH-nomogram total score based on the maximum Youden index of the ROC curve of 5-year OS. Risk stratification showed significantly better prognosis in the low-risk group, however, the high-risk group was more likely to benefit from neoadjuvant chemotherapy. CONCLUSIONS: The WCH-nomogram demonstrates superior prognostic stratification compared to prior scoring systems, effectively identifying CRLM patients who may benefit the most from neoadjuvant chemotherapy.
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Neoplasias Colorretais , Hepatectomia , Neoplasias Hepáticas , Nomogramas , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Idoso , Curva ROC , Terapia Neoadjuvante , Biomarcadores Tumorais , Adulto , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores de Risco , Estudos Retrospectivos , China , Metástase Linfática , Mutação , Carga TumoralRESUMO
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.
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Colite Ulcerativa , Sulfato de Dextrana , Microbioma Gastrointestinal , Polissacarídeos , Rosa , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Cães , Microbioma Gastrointestinal/efeitos dos fármacos , Polissacarídeos/farmacologia , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Rosa/química , Modelos Animais de Doenças , MasculinoRESUMO
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.
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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.
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Blockchain , Consenso , Inteligência , Tecnologia , Segurança ComputacionalRESUMO
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.
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Terapia de Imunossupressão , Lentinano , Animais , Camundongos , Lentinano/farmacologia , Tolerância Imunológica , Intestinos , Dexametasona/farmacologiaRESUMO
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 â6)-α-D-Galp-(1â, â4)-α-D-GalpA-(1â, α-L-Araf-(1â, â2,4)-α-D-Glcp-(1â, 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.
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Frutas , Rosa , Frutas/química , Rosa/química , Polissacarídeos/química , Macrófagos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/análiseRESUMO
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 300â °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.
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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.
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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/metabolismoRESUMO
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.
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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.