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1.
Org Biomol Chem ; 22(22): 4550-4558, 2024 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-38768281

RESUMEN

Nuclear imaging of aggregated α-synuclein pathology is an urgent clinical need for Parkinson's disease, yet promising tracers for brain α-synuclein aggregates are still rare. In this work, a class of compact benzothiazole derivatives was synthesized and evaluated for α-synuclein aggregates. Among them, azobenzothiazoles exhibited specific and selective detection of α-synuclein aggregates under physiological conditions. Fluoro-pegylated azobenzothiazole NN-F further demonstrated high-affinity binding to α-synuclein aggregates and efficient 18F-radiolabeling via nucleophilic displacement of a tosyl precursor. [18F]NN-F was stable in plasma in vitro and showed efficient brain uptake with little defluorination in vivo.


Asunto(s)
Benzotiazoles , Encéfalo , Radioisótopos de Flúor , Agregado de Proteínas , alfa-Sinucleína , alfa-Sinucleína/metabolismo , alfa-Sinucleína/química , Radioisótopos de Flúor/química , Benzotiazoles/química , Benzotiazoles/síntesis química , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagen , Animales , Humanos , Ratones , Estructura Molecular , Tomografía de Emisión de Positrones
2.
Environ Sci Technol ; 58(22): 9815-9827, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38768015

RESUMEN

Tropical small island developing states (SIDS), with their geographical isolation and limited resources, heavily rely on the fisheries industry for food and revenue. The presence of marine lipophilic phycotoxins (MLPs) poses risks to their economy and human health. To understand the contamination status and potential risks, the Republic of Kiribati was selected as the representative tropical SIDS and 55 species of 256 coral reef fish encompassing multiple trophic levels and feeding strategies were collected to analyze 17 typical MLPs. Our results showed that the potential risks of ciguatoxins were the highest and approximately 62% of fish species may pose risks for consumers. Biomagnification of ciguatoxins was observed in the food web with a trophic magnification factor of 2.90. Brevetoxin-3, okadaic acid, and dinophysistoxin-1 and -2 were first reported, but the risks posed by okadaic acid and dinophysistoxins were found to be negligible. The correlation analysis revealed that fish body size and trophic position are unreliable metrics to indicate the associated risks and prevent the consumption of contaminated fish. The potential risks of MLPs in Kiribati are of concern, and our findings can serve as valuable inputs for developing food safety policies and fisheries management strategies specific to tropical SIDS contexts.


Asunto(s)
Peces , Toxinas Marinas , Animales , Cadena Alimentaria , Islas , Humanos , Medición de Riesgo , Clima Tropical , Ciguatoxinas/toxicidad
3.
Sci Rep ; 14(1): 10348, 2024 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710798

RESUMEN

The complete compound of gefitinib is effective in the treatment of lung adenocarcinoma. However, the effect on lung adenocarcinoma (LUAD) during its catabolism has not yet been elucidated. We carried out this study to examine the predictive value of gefitinib metabolism-related long noncoding RNAs (GMLncs) in LUAD patients. To filter GMLncs and create a prognostic model, we employed Pearson correlation, Lasso, univariate Cox, and multivariate Cox analysis. We combined risk scores and clinical features to create nomograms for better application in clinical settings. According to the constructed prognostic model, we performed GO/KEGG and GSEA enrichment analysis, tumor immune microenvironment analysis, immune evasion and immunotherapy analysis, somatic cell mutation analysis, drug sensitivity analysis, IMvigor210 immunotherapy validation, stem cell index analysis and real-time quantitative PCR (RT-qPCR) analysis. We built a predictive model with 9 GMLncs, which showed good predictive performance in validation and training sets. The calibration curve demonstrated excellent agreement between the expected and observed survival rates, for which the predictive performance was better than that of the nomogram without a risk score. The metabolism of gefitinib is related to the cytochrome P450 pathway and lipid metabolism pathway, and may be one of the causes of gefitinib resistance, according to analyses from the Gene Set Enrichment Analysis (GSEA), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Immunological evasion and immunotherapy analysis revealed that the likelihood of immune evasion increased with risk score. Tumor microenvironment analysis found most immune cells at higher concentrations in the low-risk group. Drug sensitivity analysis found 23 sensitive drugs. Twenty-one of these drugs exhibited heightened sensitivity in the high-risk group. RT-qPCR analysis validated the characteristics of 9 GMlncs. The predictive model and nomogram that we constructed have good application value in evaluating the prognosis of patients and guiding clinical treatment.


Asunto(s)
Adenocarcinoma del Pulmón , Resistencia a Antineoplásicos , Gefitinib , Neoplasias Pulmonares , ARN Largo no Codificante , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Gefitinib/uso terapéutico , Gefitinib/farmacología , ARN Largo no Codificante/genética , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/metabolismo , Pronóstico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Resistencia a Antineoplásicos/genética , Nomogramas , Femenino , Masculino , Regulación Neoplásica de la Expresión Génica , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Persona de Mediana Edad , Anciano
4.
Artículo en Inglés | MEDLINE | ID: mdl-38779734

RESUMEN

AIMS: The aim of this study was to investigate the role of human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-Exo) in regulating the intestinal type 2 immune response for either protection or therapy. BACKGROUND: hUCMSC-Exo was considered a novel cell-free therapeutic product that shows promise in the treatment of various diseases. Type 2 immunity is a protective immune response classified as T-helper type 2 (Th2) cells and is associated with helminthic infections and allergic diseases. The effect of hUCMSC-Exo on intestinal type 2 immune response is not clear. METHOD: C57BL/6 mice were used to establish intestinal type 2 immune response by administering of H.poly and treated with hUCMSC-Exo before or after H.poly infection. Intestinal organoids were isolated and co-cultured with IL-4 and hUCMSC-Exo. Then, we monitored the influence of hUCMSC-Exo on type 2 immune response by checking adult worms, the hyperplasia of tuft and goblet cells. RESULT: hUCMSC-Exo significantly delays the colonization of H.poly in subserosal layer of duodenum on day 7 post-infection and promotes the hyperplasia of tuft cells and goblet cells on day 14 post-infection. HUCMSC-Exo enhances the expansion of tuft cells in IL-4 treated intestinal organoids, and promotes lytic cell death. CONCLUSION: Our study demonstrates hUCMSC-Exo may benefit the host by increasing the tolerance at an early infection stage and then enhancing the intestinal type 2 immune response to impede the helminth during Th2 priming. Our results show hUCMSC-Exo may be a positive regulator of type 2 immune response, suggesting hUCMSC-Exo has a potential therapeutic effect on allergic diseases.

5.
Ecol Evol ; 14(4): e11244, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38590550

RESUMEN

The mutualistic network of plant-pollinator also involves interspecific pollination caused by pollinator sharing. Plant-pollinator networks are commonly based on flower visit observations, which may not adequately represent the actual pollen transfer between co-flowering plant species. Here, we compared the network structure of plant-pollinator interactions based on flower visits (FV) and pollen loads (PL) on the bodies of pollinators and tested how the degree of pollinator sharing in the two networks affected heterospecific pollen transfer (HPT) between plant species in a subalpine meadow. The FV and PL networks were largely overlapped. PL network included more links than FV network. The positions of plant and pollinator species in the FV and PL networks were positively correlated, indicating that both networks could detect major plant-pollinator interactions. The degree of pollinator sharing, based on either the FV or the PL network, positively influenced the amount of heterospecific pollen transferred between plant species pairs. However, the degree of pollinator sharing had a low overall explanatory power for HPT, and the explanatory powers of the FV and PL networks were similar. Overall, our study highlights the importance of FV and PL for understanding the drivers and outcomes of plant-pollinator interactions, as well as their relevance to HPT.

6.
Biomed Rep ; 20(5): 78, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38590946

RESUMEN

The coronavirus disease 2019 (COVID-19) vaccination is the most effective way to prevent COVID-19. However, for chronic kidney disease patients on long-term dialysis, there is a lack of evidence regarding the efficacy and safety of the immune response to the vaccine. The present meta-analysis explores the efficacy and safety of COVID-19 vaccine in the immune response of patients with chronic kidney disease (CKD) undergoing dialysis. PubMed, Web of Science, Science Direct, and Cochrane Library databases were systematically searched from January 1, 2020, to December 31, 2022. Data analysis was performed using REVMAN 5.1s and Stata14 software. Baseline data and endpoint events were extracted, mainly including age, sex, dialysis vintage, body mass index (BMI), vaccine type and dose, history of COVID-19 infection, seropositivity rate, antibody titer, pain at injection site, headache and other safety events. The meta-analysis included 33 trials involving 81,348 patients. The immune efficacy of patients with CKD and dialysis was 80% (95 CI, 73-87%). The seropositivity rate of individuals without COVID-19 infection was 76.48% (3,824/5,000), while the seropositivity rate of individuals with COVID-19 infection was 80.82% (1,858/2,299). The standard mean difference of antibody titers in CKD and dialysis patients with or without COVID-19 infection was 27.73 (95% CI, -19.58-75.04). A total of nine studies reported the most common adverse events: Pain at the injection site, accounting for 18% (95 CI, 6-29%), followed by fatigue and headache, accounting for 8 (95 CI, 4-13%) and 6% (95 CI, 2-9%), respectively. COVID-19 vaccine benefitted patients with CKD undergoing dialysis with seropositivity rate ≥80%. Adverse events such as fatigue, headache, and pain at the injection site may occur after COVID-19 vaccination but the incidence is low.

7.
Curr Pharm Des ; 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38584553

RESUMEN

BACKGROUND: Targeting immunogenic cell death (ICD) is considered a promising therapeutic strategy for cancer. However, the commonly identified ICD inducers promote the expression of programmed cell death ligand 1 (PD-L1) in tumor cells, thus aiding them to evade the recognition and killing by the immune system. Therefore, the finding of novel ICD inducers to avoid enhanced PD-L1 expression is of vital significance for cancer therapy. Celastrol (CeT), a triterpene isolated from Tripterygium wilfordii Hook. F induces various forms of cell death to exert anti-cancer effects, which may make celastrol an attractive candidate as an inducer of ICD. METHODS: In the present study, bioinformatics analysis was combined with experimental validation to explore the underlying mechanism by which CeT induces ICD and regulates PD-L1 expression in clear cell renal cell carcinoma (ccRCC). RESULTS: The results showed that EGFR, IKBKB, PRKCQ and MAPK1 were the crucial targets for CeT-induced ICD, and only MAPK1 was an independent prognostic factor for the overall survival (OS) of ccRCC patients. In addition, CeT triggered autophagy and up-regulated the expressions of HMGB1 and CRT to induce ICD in 786-O cells in vitro. Importantly, CeT can down-regulate PD-L1 expression through activating autophagy. At the molecular level, CeT suppressed PD-L1 via the inhibition of MAPK1 expression. Immunologically, the core target of celastrol, MAPK1, was tightly correlated with CD8+ T cells and CD4+ T cells in ccRCC. CONCLUSION: These findings indicate that CeT not only induces ICD but also suppresses PD-L1 by down-regulating MAPK1 expression, which will provide an attractive strategy for ccRCC immunotherapy.

9.
Cell Death Dis ; 15(4): 291, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658569

RESUMEN

Annexin A2 (ANXA2) is a widely reported oncogene. However, the mechanism of ANXA2 in esophageal cancer is not fully understood. In this study, we provided evidence that ANXA2 promotes the progression of esophageal squamous cell carcinoma (ESCC) through the downstream target threonine tyrosine kinase (TTK). These results are consistent with the up-regulation of ANXA2 and TTK in ESCC. In vitro experiments by knockdown and overexpression of ANXA2 revealed that ANXA2 promotes the progression of ESCC by enhancing cancer cell proliferation, migration, and invasion. Subsequently, animal models also confirmed the role of ANXA2 in promoting the proliferation and metastasis of ESCC. Mechanistically, the ANXA2/TTK complex activates the Akt/mTOR signaling pathway and accelerates epithelial-mesenchymal transition (EMT), thereby promoting the invasion and metastasis of ESCC. Furthermore, we identified that TTK overexpression can reverse the inhibition of ESCC invasion after ANXA2 knockdown. Overall, these data indicate that the combination of ANXA2 and TTK regulates the activation of the Akt/mTOR pathway and accelerates the progression of ESCC. Therefore, the ANXA2/TTK/Akt/mTOR axis is a potential therapeutic target for ESCC.


Asunto(s)
Anexina A2 , Proliferación Celular , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal , Neoplasias Esofágicas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Humanos , Serina-Treonina Quinasas TOR/metabolismo , Anexina A2/metabolismo , Anexina A2/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/genética , Animales , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/genética , Ratones Desnudos , Ratones , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/metabolismo , Carcinoma de Células Escamosas de Esófago/genética , Movimiento Celular , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Masculino , Ratones Endogámicos BALB C , Invasividad Neoplásica , Regulación Neoplásica de la Expresión Génica , Femenino
10.
BMC Pulm Med ; 24(1): 208, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671424

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) has been proved as a significant risk factor for deep vein thrombosis (DVT) after several waves of pandemic. This study aims to further investigate impact of COVID-19 on prognosis of DVT following anticoagulation treatment. METHODS: A total of 197 patients with initially detected DVT and meanwhile accomplishing at least 3 months anticoagulation treatment were identified from our hospital between January 2021 and December 2022. DVT characteristics, clinical data, and exposure to COVID-19 were recorded for multivariable logistic regression analysis to identify DVT aggravation related risk factors. Propensity score matching (PSM) was used to balance baseline covariates. Kaplan-Meier curves and Log-Rank test were performed to exhibit distribution of DVT aggravation among different subgroups. RESULTS: In 2022, patients exhibited higher incidence rates of DVT aggravation compared to those in 2021 (HR:2.311, P = 0.0018). The exposure to COVID-19, increased red blood cell count, increased D-dimer level and reduced prothrombin time were found to be associated with DVT aggravation (P < 0.0001, P = 0.014, P < 0.001, P = 0.024), with only exposure to COVID-19 showing a significant difference between two years (2022:59/102, 57.84%, 2021:7/88, 7.37%, P < 0.001). In PSM-matched cohorts, the risk for DVT aggravation was 3.182 times higher in COVID-19 group compared to the control group (P < 0.0001). Exposure to COVID-19 increased the risk of DVT aggravation among patients who completed three months anticoagulant therapy (HR: 5.667, P < 0.0001), but did not increase incidence rate among patients who completed more than three months anticoagulant therapy (HR:1.198, P = 0.683). For patients with distal DVT, COVID-19 was associated with a significant increased risk of DVT recurrence (HR:4.203, P < 0.0001). Regarding principal diagnoses, incidence rate of DVT aggravation was significantly higher in COVID-19 group compared to the control group (Advanced lung cancer: P = 0.011, surgical history: P = 0.0365, benign lung diseases: P = 0.0418). CONCLUSIONS: Our study reveals an increased risk of DVT aggravation following COVID-19 during anticoagulation treatment, particularly among patients with distal DVT or those who have completed only three months anticoagulant therapy. Adverse effects of COVID-19 on DVT prognosis were observed across various benign and malignant respiratory diseases. Additionally, extended-term anticoagulant therapy was identified as an effective approach to enhance DVT control among patients with COVID-19.


Asunto(s)
Anticoagulantes , COVID-19 , SARS-CoV-2 , Trombosis de la Vena , Humanos , COVID-19/complicaciones , COVID-19/epidemiología , Trombosis de la Vena/epidemiología , Trombosis de la Vena/etiología , Femenino , Masculino , Anticoagulantes/uso terapéutico , Anticoagulantes/efectos adversos , Estudios Retrospectivos , Persona de Mediana Edad , Pronóstico , Anciano , Factores de Riesgo , Incidencia , Puntaje de Propensión , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , China/epidemiología
11.
PLoS One ; 19(4): e0298470, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38683794

RESUMEN

BACKGROUND: There are various therapeutic methods for treating stage IA (T1N0M0) non-small cell lung cancer (NSCLC), but no studies have systematically assessed multiple treatments to determine the most effective therapy. METHODS: Stage IA NSCLC patient data collected between 2004 and 2018 were gathered from the Surveillance, Epidemiology, and End Results (SEER) database. Treatment modalities included observation, chemotherapy alone (CA), radiation alone (RA), radiation+chemotherapy (RC), surgery alone (SA), surgery+chemotherapy (SC), surgery+radiation (SR) and surgery+radiation+chemotherapy (SRC). Comparisons were made of overall survival (OS) and lung cancer-specific survival (LCSS) among patients based on different therapeutic methods by survival analysis. RESULTS: Ultimately, 89147 patients with stage IA NSCLC between 2004 and 2018 were enrolled in this study. The order of multiple treatment modalities based on the hazard ratio (HR) for OS for the entire cohort revealed the following results: SA (HR: 0.20), SC (HR: 0.25), SR (HR: 0.42), SRC (HR: 0.46), RA (HR: 0.56), RC (HR: 0.72), CA (HR: 0.91) (P<0.001), and observation (HR: Ref). The SA group had the best OS and LCSS, and similar results were found in most subgroup analyses (all P<0.001). The order of surgical modalities based on the HR for OS for the entire cohort revealed the following results: lobectomy (HR: 0.32), segmentectomy (HR: 0.41), wedge resection (HR: 0.52) and local tumor destruction (HR: Ref). Lobectomy had the best effects on OS and LCSS, and similar results were found in all subgroup analyses (all P<0.001). CONCLUSION: SA appeared to be the optimal treatment modality for patients with stage IA NSCLC, and lobectomy was associated with the best prognosis. There may be some indication and selection bias in our study, and the results of this study should be confirmed in a prospective study.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Estadificación de Neoplasias , Programa de VERF , Humanos , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/mortalidad , Femenino , Masculino , Anciano , Persona de Mediana Edad , Terapia Combinada , Adulto , Anciano de 80 o más Años , Análisis de Supervivencia
12.
Front Mol Biosci ; 11: 1366020, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38633216

RESUMEN

Objective: Diabetic retinopathy (DR) is a severe diabetic complication that leads to severe visual impairment or blindness. He-Ying-Qing-Re formula (HF), a traditional Chinese medicinal concoction, has been identified as an efficient therapy for DR with retinal vascular dysfunction for decades and has been experimentally reported to ameliorate retinal conditions in diabetic mice. This study endeavors to explore the therapeutic potential of HF with key ingredients in DR and its underlying novel mechanisms. Methods: Co-expression gene modules and hub genes were calculated by weighted gene co-expression network analysis (WGCNA) based on transcriptome sequencing data from high-glucose-treated adult retinal pigment epithelial cell line-19 (ARPE-19). The chromatographic fingerprint of HF was established by ultra-performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC-Q-TOF-MS). The molecular affinity of the herbal compound was measured by molecular docking. Reactive oxygen species (ROS) was measured by a DCFDA/H2DCFDA assay. Apoptosis was detected using the TUNEL Assay Kit, while ELISA, Western blot, and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) were used for detecting the cytokine, protein, and mRNA expressions, respectively. Results: Key compounds in HF were identified as luteolin, paeoniflorin, and nobiletin. For WGCNA, ME-salmon ("protein deacetylation") was negatively correlated with ME-purple ("oxidative impairment") in high-glucose-treated ARPE-19. Luteolin has a high affinity for SIRT1 and P53, as indicated by molecular docking. Luteolin has a hypoglycemic effect on type I diabetic mice. Moreover, HF and luteolin suppress oxidative stress production (ROS and MDA), inflammatory factor expression (IL-6, TNF-α, IL1-ß, and MCP-1), and apoptosis, as shown in the in vivo and in vitro experiments. Concurrently, treatment with HF and luteolin led to an upregulation of SIRT1 and a corresponding downregulation of P53. Conclusion: Using HF and its active compound luteolin as therapeutic agents offers a promising approach to diabetic retinopathy treatment. It primarily suppressed protein acetylation and oxidative stress via the SIRT1/P53 pathway in retinal pigment epithelial cells.

13.
Toxicol Res (Camb) ; 13(2): tfae064, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38680951

RESUMEN

Background: Postmenopausal osteoporosis (PMPO) is the most familiar type of osteoporosis, a silent bone disease. Casticin, a natural flavonoid constituent, improves osteoporosis in animal model. Nevertheless, the potential mechanism remains to be further explored. Methods: A model of PMPO was established in rats treated with ovariectomy (OVX) and RAW 264.7 cells induced with receptor activator of nuclear factor kappa-B ligand (RANKL). The effect and potential mechanism of casticin on PMPO were addressed by pathological staining, measurement of bone mineral density (BMD), three-point bending test, serum biochemical detection, filamentous-actin (F-actin) ring staining, TRAcP staining, reverse transcription quantitative polymerase chain reaction, western blot and examination of oxidative stress indicators. Results: The casticin treatment increased the femoral trabecular area, bone maturity, BMD, elastic modulus, maximum load, the level of calcium and estrogen with the reduced concentrations of alkaline phosphatase (ALP) and tumor necrosis factor (TNF)-α in OVX rats. An enhancement in the F-actin ring formation, TRAcP staining and the relative mRNA expression of NFATc1 and TRAP was observed in RANKL-induced RAW 264.7 cells, which was declined by the treatment of casticin. Moreover, the casticin treatment reversed the reduced the relative protein expression of Nrf2 and HO-1 and the concentrations of superoxide dismutase and glutathione peroxidase, and the increased content of malondialdehyde both in vivo and in vitro. Conclusion: Casticin improved bone density, bone biomechanics, the level of calcium and estrogen, the release of pro-inflammatory factor and oxidative stress to alleviate osteoporosis, which was associated with the upregulation of Nrf2/HO-1 pathway.

14.
Materials (Basel) ; 17(8)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38673197

RESUMEN

In order to enhance the quality of diamond composite materials, this work employs a Cu-Co-Fe and Ni-Cr-Cu pre-alloyed powder mixture as a transition layer, and utilizes laser-welding technology for saw blade fabrication. By adjusting the laser-welding process parameters, including welding speed and welding power, well-formed welded joints were achieved, and the microstructure and mechanical properties of the welded joints were investigated. The results demonstrate that the best welding performance was achieved at a laser power of 1600 W and a welding speed of 1400 mm/min, with a remarkable tooth engagement strength of up to 819 MPa. The fusion zone can be divided into rich Cu phase and rich Fe phase regions, characterized by coarse grains without apparent preferred orientation. The microstructure of the heat-affected zone primarily consists of high-hardness brittle quenched needle-like martensite, exhibiting a sharp increase in microhardness up to 550 HV. Fracture occurred at the boundary between the fusion zone and the heat-affected zone of the base material, where stress concentration was observed. By adjusting the welding parameters and transition layer materials, the mechanical properties of the joints were improved, thereby achieving a reliable connection between diamond composite materials and the metal substrate.

15.
Artículo en Inglés | MEDLINE | ID: mdl-38504579

RESUMEN

Aims: Intervertebral disc degeneration (IDD) is closely related to low back pain, which is a prevalent age-related problem worldwide; however, the mechanism underlying IDD is unknown. Glutamine, a free amino acid prevalent in plasma, is recognized for its anti-inflammatory and antioxidant properties in various diseases, and the current study aims to clarify the effect and mechanism of glutamine in IDD. Results: A synergistic interplay was observed between pyroptosis and ferroptosis within degenerated human disc specimens. Glutamine significantly mitigated IDD in both ex vivo and in vivo experimental models. Moreover, glutamine protected nucleus pulposus (NP) cells after tert-butyl hydroperoxide (TBHP)-induced pyroptosis, ferroptosis, and extracellular matrix (ECM) degradation in vitro. Glutamine protected NP cells from TBHP-induced ferroptosis by promoting the nuclear factor erythroid 2-related factor 2 (Nrf2) accumulation by inhibiting its ubiquitin-proteasome degradation and inhibiting lipid oxidation. Innovation and Conclusions: A direct correlation is evident in the progression of IDD between the processes of pyroptosis and ferroptosis. Glutamine suppressed oxidative stress-induced cellular processes, including pyroptosis, ferroptosis, and ECM degradation through deubiquitinating Nrf2 and inhibiting lipid oxidation in NP cells. Glutamine is a promising novel therapeutic target for the management of IDD.

16.
Sensors (Basel) ; 24(6)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38543990

RESUMEN

The evaluation of blasting vibrations primarily hinges on two physical quantities: velocity and acceleration. A significant challenge arises when attempting to reference the two types of vibration data in relation to one another, such as different types of seismometers, noise, etc., necessitating a method for their equivalent transformation. To address this, a transformation method is discussed in detail with a case study, and equations for the ratio (Ra) of the particle peak velocity (PPV) to the particle peak acceleration (PPA) are proposed. The findings are twofold: (1) The conventional data conversion processes often suffer from low accuracy due to the presence of trend terms and noise in the signal. To mitigate this, the built-in MATLAB function is used for trend term elimination, complemented by a combined approach that integrates CEEMDAN with WD/WDP for noise reduction. These significantly enhance the accuracy of the transformation. (2) This analysis reveals a positive power function correlation between Ra and the propagation distance of the blast vibrations, contrasted by a negative correlation with the maximum charge per delay. Intriguingly, the Ra values observed in pre-splitting blasting operations are consistently lower than those in bench blasting. The established Ra equations offer a rapid, direct method for assessing the transformation between the PPV and PPA, providing valuable insights for the optimization of blasting design.

17.
Commun Biol ; 7(1): 325, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38486093

RESUMEN

Regulating metabolic disorders has become a promising focus in treating intervertebral disc degeneration (IDD). A few drugs regulating metabolism, such as atorvastatin, metformin, and melatonin, show positive effects in treating IDD. Glutamine participates in multiple metabolic processes, including glutaminolysis and glycolysis; however, its impact on IDD is unclear. The current study reveals that glutamine levels are decreased in severely degenerated human nucleus pulposus (NP) tissues and aging Sprague-Dawley (SD) rat nucleus pulposus tissues, while lactate accumulation and lactylation are increased. Supplementary glutamine suppresses glycolysis and reduces lactate production, which downregulates adenosine-5'-monophosphate-activated protein kinase α (AMPKα) lactylation and upregulates AMPKα phosphorylation. Moreover, glutamine treatment reduces NP cell senescence and enhances autophagy and matrix synthesis via inhibition of glycolysis and AMPK lactylation, and glycolysis inhibition suppresses lactylation. Our results indicate that glutamine could prevent IDD by glycolysis inhibition-decreased AMPKα lactylation, which promotes autophagy and suppresses NP cell senescence.


Asunto(s)
Degeneración del Disco Intervertebral , Ratas , Animales , Humanos , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/metabolismo , Ratas Sprague-Dawley , Glutamina , Proteínas Quinasas Activadas por AMP , Autofagia , Lactatos/farmacología , Lactatos/uso terapéutico
18.
PLoS One ; 19(3): e0299273, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38452128

RESUMEN

PURPOSE: This study aims to evaluate the efficacy and satisfaction of using a multi-angle laser device (MLD) for C-arm fluoroscopy to assist novice learners during lumbar spine surgery. METHODS: Forty novice learners were randomly assigned to Group A using an MLD-equipped C-arm or Group B using a traditional C-arm. Both groups performed X-ray fluoroscopy on a lumbar spine model in supine and rotated positions. Time, number of shots, and deviation from the target were compared. A questionnaire was used to assess the learning experience. RESULTS: Group A required less time (13.66 vs. 25.63 min), and fewer shots (15.05 vs. 32.50), and had a smaller deviation (22.9% vs. 61.5%) than Group B (all p<0.05). The questionnaire revealed higher scores in Group A for comfort, efficiency, and knowledge mastery (all p<0.05). CONCLUSION: The MLD significantly improves novice learning of C-arm fluoroscopy during lumbar spine surgery.


Asunto(s)
Vértebras Lumbares , Cirugía Asistida por Computador , Fluoroscopía , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Encuestas y Cuestionarios , Humanos
19.
NPJ Vaccines ; 9(1): 65, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38514651

RESUMEN

Lumpy skin disease virus (LSDV) is a poxvirus that mainly affects cattle and can lead to symptoms such as severe reduction in milk production as well as infertility and mortality, which has resulted in dramatic economic loss in affected countries in Africa, Europe, and Asia. In this study, we successfully isolated two strains of LSDV from different geographical regions in China. Comparative genomic analyses were performed by incorporating additional LSDV whole genome sequences reported in other areas of Asia. Our analyses revealed that LSDV exhibited an 'open' pan-genome. Phylogenetic analysis unveiled distinct branches of LSDV evolution, signifying the prevalence of multiple lineages of LSDV across various regions in Asia. In addition, a reporter LSDV expressing eGFP directed by a synthetic poxvirus promoter was generated and used to evaluate the cell tropism of LSDV in various mammalian and avian cell lines. Our results demonstrated that LSDV replicated efficiently in several mammalian cell lines, including human A549 cells. In conclusion, our results underscore the necessity for strengthening LSD outbreak control measures and continuous epidemiological surveillance.

20.
Dalton Trans ; 53(12): 5553-5561, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38426302

RESUMEN

Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs) are considered as next-generation of NIR light sources for spectroscopy. However, it is still a challenge to develop an inexpensive broadband NIR phosphor with relatively long-wavelength (λem > 800 nm) emission. In this work, an octahedral Al3+-containing pyrophosphate Al0.5Ta0.5P2O7 with a cubic structure was chosen as a host for Cr3+. Synthesizing this material indicates that this phosphor exhibits a broadband NIR emission peaking at 850 nm with a full width at half maximum (FWHM) of 155 nm under 465 nm excitation. The crystal structure, morphology, local structure, and photoluminescence properties of this material were investigated in detail. The results revealed a full understanding of this new material. A NIR pc-LED device fabricated by using this material combined with a 450 nm LED chip generates a NIR output power of 10.7 mW and a NIR photoelectric conversion efficiency of 3.4% under a 100 mA driving current, which shows the possibility of this material to be utilized in NIR pc-LED applications. Moreover, this material exhibits a linear relationship between emission intensity, decay time and temperature in a wide temperature range, implying that excellent multi-model temperature sensing applications can be expected.

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