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1.
Materials (Basel) ; 17(13)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38998293

RESUMEN

As a new type of high-performance material, gradient structural steel is widely used in engineering fields due to its unique microstructure and excellent mechanical properties. For the prevalent fatigue failure problem, the rate of change in the local grain size gradients along the structure (referred to as the gradient rate) is a key parameter in the design of gradient structures, which significantly affects the fatigue performance of gradient structural steel. In this study, a new method of 'Voronoi primary + secondary modeling' is adopted to successfully establish three typical high-strength steel models corresponding to the convex-, linear-, and concave-type gradient rates for gradient structures, focusing on the stress-strain response and crack propagation in structural steel with different gradient rates under cyclic loading. It was found that the concave gradient rate structural model is dominated by finer grains with larger volume fraction, which is conducive to hindering fatigue crack propagation and has the longest fatigue life, which is 16.16% longer than that of the linear gradient rate structure and 23.66% longer than that of the convex gradient rate structure. The simulation results in this study are consistent with the relevant experimental phenomena. Therefore, when regulating the gradient rate, priority should be given to increasing the volume fraction of fine grains and designing a gradient rate structure dominated by fine grains to improve the fatigue life of the material. This study presents a new strategy for designing engineering materials with better service performance.

2.
Cancer Rep (Hoboken) ; 7(6): e2103, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39031740

RESUMEN

BACKGROUND: In December 2022, a large-scale epidemic occurred in China due to Omicron variant of SARS-CoV-2. This study explored risk factors for Omicron infection in transplant recipients at our institution and investigated the factors influencing the severity of SARS-CoV-2 Omicron infection among recipients of allo-HSCT. METHODS: This single-center study investigated totally 63 allogeneic hematopoietic stem cell transplant patients infected with Omicron variant at the Beijing GoBroad Boren Hospital Transplant Center during December 2022 and analyzed their risk factors. RESULTS: The study included 63 allogeneic hematopoietic stem cell transplant patients who developed Omicron infection. There were 34 mild and 29 moderate to severe cases. Their median age was 22 years (range, 1-65 years), with the male-to-female ratio being 1:1.1. Acute myeloid leukemia (53.97%), acute lymphoblastic leukemia (42.86%), and non-Hodgkin lymphoma (3.17%) were underlying diseases. The median time between HCT and Omicron infection was 8.45 months. Significant predictive factors for moderate to severe Omicron infection included older age (p < .0001), cGVHD (p = .0195), concurrent bacterial infection (p < .0001), low absolute lymphocyte count (p = .026), low CD4/CD8 ratio (p = .0091), high CRP (p < .0001), high serum ferritin (p = .0023), high D-dimer (p < .0001), low CD4 absolute count (p = .0057), and low B-cell absolute count (p = .0154). A moderate to high HCT-CI score tended to be associated with moderate to severe infection (p = .0596). CONCLUSION: This study indicates that risk factors for severe Omicron infection include certain clinical characteristics, such as age, cGVHD, and inflammatory response.


Asunto(s)
COVID-19 , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/complicaciones , Masculino , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Femenino , Adulto , Persona de Mediana Edad , Adolescente , Factores de Riesgo , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/epidemiología , SARS-CoV-2/aislamiento & purificación , Adulto Joven , Niño , Anciano , Preescolar , Lactante , China/epidemiología , Trasplante Homólogo/efectos adversos , Índice de Severidad de la Enfermedad , Estudios Retrospectivos
3.
Front Vet Sci ; 11: 1417348, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38933700

RESUMEN

Porcine epidemic diarrhea virus (PEDV) is a highly infectious pathogen that targets pig intestines to cause disease. It is globally widespread and causes huge economic losses to the pig industry. PEDV N protein is the protein that constitutes the core of PEDV virus particles, and most of it is expressed in the cytoplasm, and a small part can also be expressed in the nucleus. However, the role of related proteins in host nucleotide metabolic pathways in regulating PEDV replication have not been fully elucidated. In this study, PEDV-N-labeled antibodies were co-immunoprecipitated and combined with LC-MS to screen for host proteins that interact with N proteins. Bioinformatics analyses showed that the selected host proteins were mainly enriched in metabolic pathways. Moreover, co-immunoprecipitation and confocal microscopy confirmed that the second-largest subunit of RNA polymerase II (RPB2) and uridine phosphorylase 1 (UPP1) interacted with the N protein. RPB2 is the main subunit of RNA polymerase II and plays an important role in eukaryotic transcription. UPP1 is an enzyme that catalyzes reversible phosphorylation of uridine to uracil and ribo-1-phosphate to promote catabolism and bio anabolism. RPB2 overexpression significantly promoted viral replication, whereas UPP1 overexpression significantly inhibited viral replication. Studies on interactions between the PEDV N and host proteins are helpful in elucidating the pathogenesis and immune escape mechanism of PEDV.

4.
Virology ; 597: 110145, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38941747

RESUMEN

African swine fever virus (ASFV), which was first identified in northern China in 2018, causes high mortality in pigs. Since the I73R protein in ASFV is abundantly expressed during the early phase of virus replication, it can be used as a target protein for early diagnosis. In this study, the I73R protein of ASFV was expressed, and we successfully prepared a novel monoclonal antibody (mAb), 8G11D7, that recognizes this protein. Through both indirect immunofluorescence and Western blotting assays, we demonstrated that 8G11D7 can detect ASFV strains. By evaluating the binding of the antibody to a series of I73R-truncated peptides, the definitive epitope recognized by the monoclonal antibody 8G11D7 was determined to be 58 DKTNTIYPP 66. Bioinformatic analysis revealed that the antigenic epitope had a high antigenic index and conservatism. This study contributes to a deeper understanding of ASFV protein structure and function, helping establish ASFV-specific detection method.


Asunto(s)
Virus de la Fiebre Porcina Africana , Fiebre Porcina Africana , Anticuerpos Monoclonales , Anticuerpos Antivirales , Epítopos , Virus de la Fiebre Porcina Africana/inmunología , Virus de la Fiebre Porcina Africana/genética , Animales , Anticuerpos Monoclonales/inmunología , Porcinos , Epítopos/inmunología , Fiebre Porcina Africana/virología , Fiebre Porcina Africana/inmunología , Fiebre Porcina Africana/diagnóstico , Anticuerpos Antivirales/inmunología , Proteínas Virales/inmunología , Proteínas Virales/genética , Ratones , Antígenos Virales/inmunología , Antígenos Virales/genética , Ratones Endogámicos BALB C , Mapeo Epitopo
5.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1112-1122, 2024 Apr 18.
Artículo en Chino | MEDLINE | ID: mdl-38884246

RESUMEN

River water quality is influenced by natural processes and human activities. Multi-scale landscape patterns can affect river water quality by altering the generation and transport processes of pollutants at different spatial scales. Taking Taizi River Basin in Northeast China as an example, we analyzed the relationship between landscape patterns and non-point source pollution in rivers based on water quality monitoring data and land use data by using correlation analysis and redundancy analysis methods. We aimed to determine the key spatial scales for the responses of landscape patterns to non-point source pollution and identify the key landscape indices influencing river non-point source pollution. The results showed that water quality of Taizi River Basin had seasonal differences, with better water quality during the flood season than non-flood season. Spatially, total nitrogen (TN) and total phosphorus (TP) were higher at the confluence points of tributaries and downstream areas. The impact of landscape patterns on non-point source pollution was stronger during the non-flood season than the flood season, while the influence on TN was stronger than on TP. At the spatial scale of within 500 m buffer zone during the flood season and at the sub-watershed scale during the non-flood season, landscape patterns showed the highest explanatory power for the variations of TN and TP. At the type level, built-up land, cropland, and bare land were positively correlated with TN and TP, while forest was negatively correlated with TN and TP, which were the key types influencing non-point source pollution. At the landscape level, patch density, percentage of like adjacencies, and contagion index were key indicators affecting watershed water quality. Lower patch density was associated with better connectivity and aggregation of "sink" landscapes, leading to better purification effects on TN, but more pronounced retention effects on TP. Conversely, higher landscape diversity and denser pattern of multiple types would cause the deterioration of water quality. Our results suggested that rational allocation of landscape types within the watershed and riparian buffer zones, appropriately enriching landscape diversity, and optimizing landscape aggregation and connectivity would be effective measures for improving water quality and achieving sustainable ecological management.


Asunto(s)
Monitoreo del Ambiente , Fósforo , Ríos , Contaminantes Químicos del Agua , China , Ríos/química , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Fósforo/análisis , Ecosistema , Nitrógeno/análisis , Contaminación Difusa/análisis , Contaminación Difusa/prevención & control , Calidad del Agua , Análisis Espacial
6.
BMC Pediatr ; 24(1): 390, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858617

RESUMEN

BACKGROUND: Oculocutaneous albinism (OCA) is a group of autosomal recessive hereditary disorders that affect melanin biosynthesis, resulting in abnormalities in hair, skin, and eyes. Retinopathy of prematurity (ROP) is a proliferative retinopathy mainly observed in premature infants with low birth weight and early gestational age, but it can also affect full-term infants or children with normal weight, particularly in developing countries. The coexistence of ROP and OCA is rare. There is limited documentation regarding treatment approaches, with few studies reporting positive outcomes with laser treatment due to the absence of melanin pigment. This study discusses the treatment challenges in a female infant diagnosed with ROP and OCA, and underscores the importance of genetic analysis in guiding therapeutic decisions for this rare comorbid condition. CASE PRESENTATION: The study presents a case of ROP occurring concurrently with OCA. Genetic testing revealed two variants, c.727C > T (p.R243C) and c.1832 T > C (p.L611P), in the OCA2 gene, inherited from the patient's mother and father, respectively. The identified mutations were consistent with a diagnosis of OCA2, classified as a subtype of OCA. The patient initially received intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection, followed by laser photocoagulation therapy for a recurrent event. A favorable outcome was observed during the 2-month follow-up period. CONCLUSIONS: The co-occurrence of ROP and OCA is a rare phenomenon, and this is the first recorded case in the Chinese population. The current case supports the use of laser as the primary treatment modality for ROP in OCA2 patients with partial pigmentation impairment. Furthermore, genetic analysis can aid in predicting the effectiveness of laser photocoagulation in this patient population.


Asunto(s)
Albinismo Oculocutáneo , Retinopatía de la Prematuridad , Humanos , Femenino , Albinismo Oculocutáneo/genética , Albinismo Oculocutáneo/complicaciones , Albinismo Oculocutáneo/terapia , Retinopatía de la Prematuridad/genética , Retinopatía de la Prematuridad/terapia , Retinopatía de la Prematuridad/complicaciones , Recién Nacido , Proteínas de Transporte de Membrana/genética , Mutación , Inhibidores de la Angiogénesis/uso terapéutico , Coagulación con Láser , Bevacizumab/uso terapéutico
7.
Front Cardiovasc Med ; 11: 1344764, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38725834

RESUMEN

Objective: Several observational studies have shown that high-volume and high-intensity exercise training increases the prevalence and severity of coronary atherosclerosis, but the causal effect still remains uncertain. This study aims to explore the causal relationship between the volume of strenuous exercise (SE) and coronary atherosclerosis (CA) using the Mendelian randomization (MR) method. Method: The exposure factors were two basic parameters of the volume of strenuous exercise (duration and frequency of strenuous exercise), the outcome factor was coronary atherosclerosis, and the relevant genetic loci were extracted from the summary data of the genome-wide association study (GWAS) as the instrumental variables, and MR analyses were performed using the inverse variance weighting (IVW) method, the weighted median method, and the MR-egger method. Sensitivity analyses were performed using heterogeneity analysis, pleiotropy analysis, and the "leave-one-out" method. The original results were tested using other coronary atherosclerosis data sets. Result: IVW results showed no causal association between duration of strenuous exercise (DOSE) [OR = 0.9937, 95% CI (0.9847, 1.0028), P = 0.1757] and frequency of strenuous exercise (FOSE) in the last 4 weeks [OR = 0.9930, 95% CI (0.9808, 1.0054), P = 0.2660] and coronary atherosclerosis. All of the above results were validated with other coronary atherosclerosis data sets. Conclusion: The present study supports that the causal association of duration and frequency of SE with CA was not found, and provides valuable insights into the choice of scientific and correct volume of SE to cardiac rehabilitation (CR).

8.
Healthcare (Basel) ; 12(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38786438

RESUMEN

Disabled older adults exhibited a higher risk for cognitive impairment. Early identification is crucial in alleviating the disease burden. This study aims to develop and validate a prediction model for identifying cognitive impairment among disabled older adults. A total of 2138, 501, and 746 participants were included in the development set and two external validation sets. Logistic regression, support vector machine, random forest, and XGBoost were introduced to develop the prediction model. A nomogram was further established to demonstrate the prediction model directly and vividly. Logistic regression exhibited better predictive performance on the test set with an area under the curve of 0.875. It maintained a high level of precision (0.808), specification (0.788), sensitivity (0.770), and F1-score (0.788) compared with the machine learning models. We further simplified and established a nomogram based on the logistic regression, comprising five variables: age, daily living activities, instrumental activity of daily living, hearing impairment, and visual impairment. The areas under the curve of the nomogram were 0.871, 0.825, and 0.863 in the internal and two external validation sets, respectively. This nomogram effectively identifies the risk of cognitive impairment in disabled older adults.

9.
Front Microbiol ; 15: 1380578, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38577683

RESUMEN

Introduction: Porcine epidemic diarrhea (PED) is an acute, highly contagious, and high-mortality enterophilic infectious disease caused by the porcine epidemic diarrhea virus (PEDV). PEDV is globally endemic and causes substantial economic losses in the swine industry. The PEDV E protein is the smallest structural protein with high expression levels that interacts with the M protein and participates in virus assembly. However, how the host proteins interact with E proteins in PEDV replication remains unknown. Methods: We identified host proteins that interact with the PEDV E protein using a combination of PEDV E protein-labeled antibody co-immunoprecipitation and tandem liquid-chromatography mass-spectroscopy (LC-MS/MS). Results: Bioinformatical analysis showed that in eukaryotes, ribosome biogenesis, RNA transport, and amino acid biosynthesis represent the three main pathways that are associated with the E protein. The interaction between the E protein and isocitrate dehydrogenase [NAD] ß-subunit (NAD-IDH-ß), DNA-directed RNA polymerase II subunit RPB9, and mRNA-associated protein MRNP 41 was validated using co-immunoprecipitation and confocal assays. NAD-IDH-ß overexpression significantly inhibited viral replication. Discussion: The antiviral effect of NAD-IDH-ß suggesting that the E protein may regulate host metabolism by interacting with NAD-IDH-ß, thereby reducing the available energy for viral replication. Elucidating the interaction between the PEDV E protein and host proteins may clarify its role in viral replication. These results provide a theoretical basis for the study of PEDV infection mechanism and antiviral targets.

10.
Cell Rep ; 43(4): 114051, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38564334

RESUMEN

Uropathogenic Escherichia coli (UPEC) is the most common causative agent of urinary tract infection (UTI). UPEC invades bladder epithelial cells (BECs) via fusiform vesicles, escapes into the cytosol, and establishes biofilm-like intracellular bacterial communities (IBCs). Nucleoside-diphosphate kinase (NDK) is secreted by pathogenic bacteria to enhance virulence. However, whether NDK is involved in UPEC pathogenesis remains unclear. Here, we find that the lack of ndk impairs the colonization of UPEC CFT073 in mouse bladders and kidneys owing to the impaired ability of UPEC to form IBCs. Furthermore, we demonstrate that NDK inhibits caspase-1-dependent pyroptosis by consuming extracellular ATP, preventing superficial BEC exfoliation, and promoting IBC formation. UPEC utilizes the reactive oxygen species (ROS) sensor OxyR to indirectly activate the regulator integration host factor, which then directly activates ndk expression in response to intracellular ROS. Here, we reveal a signaling transduction pathway that UPEC employs to inhibit superficial BEC exfoliation, thus facilitating acute UTI.


Asunto(s)
Caspasa 1 , Infecciones por Escherichia coli , Nucleósido-Difosfato Quinasa , Piroptosis , Infecciones Urinarias , Escherichia coli Uropatógena , Escherichia coli Uropatógena/patogenicidad , Animales , Infecciones Urinarias/microbiología , Infecciones Urinarias/patología , Ratones , Caspasa 1/metabolismo , Nucleósido-Difosfato Quinasa/metabolismo , Nucleósido-Difosfato Quinasa/genética , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/patología , Especies Reactivas de Oxígeno/metabolismo , Ratones Endogámicos C57BL , Humanos , Femenino , Vejiga Urinaria/microbiología , Vejiga Urinaria/patología , Células Epiteliales/microbiología , Células Epiteliales/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Transducción de Señal
11.
BMC Vet Res ; 20(1): 134, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570774

RESUMEN

BACKGROUND: Porcine acute diarrhea syndrome coronavirus (SADS-CoV) is one of the novel pathogens responsible for piglet diarrhea, contributing to substantial economic losses in the farming sector. The broad host range of SADS-CoV raises concerns regarding its potential for cross-species transmission. Currently, there are no effective means of preventing or treating SADS-CoV infection, underscoring the urgent need for identifying efficient antiviral drugs. This study focuses on evaluating quercetin as an antiviral agent against SADS-CoV. RESULTS: In vitro experiments showed that quercetin inhibited SADS-CoV proliferation in a concentration-dependent manner, targeting the adsorption and replication stages of the viral life cycle. Furthermore, quercetin disrupts the regulation of the P53 gene by the virus and inhibits host cell cycle progression induced by SADS-CoV infection. In vivo experiments revealed that quercetin effectively alleviated the clinical symptoms and intestinal pathological damage caused by SADS-CoV-infected piglets, leading to reduced expression levels of inflammatory factors such as TLR3, IL-6, IL-8, and TNF-α. CONCLUSIONS: Therefore, this study provides compelling evidence that quercetin has great potential and promising applications for anti- SADS-CoV action.


Asunto(s)
Alphacoronavirus , Infecciones por Coronavirus , Coronavirus , Enfermedades de los Porcinos , Porcinos , Animales , Coronavirus/genética , Quercetina/farmacología , Quercetina/uso terapéutico , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/veterinaria , Diarrea/veterinaria , Enfermedades de los Porcinos/tratamiento farmacológico
13.
Braz J Med Biol Res ; 57: e13351, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38511770

RESUMEN

The complex pathogenesis of castration-resistant prostate cancer (CRPC) makes it challenging to identify effective treatment methods. Matrix metalloproteinase (MMP)-12 can degrade elastin as well as various extracellular matrix (ECM) components, which is associated with cancer progression. However, the relationship between MMP-12 and CRPC progression is poorly understood. In this study, we observed the effect of MMP-12 on the progression of CRPC and further explored its potential mechanism of action. High levels of MMP-12 were observed in patients with CRPC. We therefore developed cell co-culture and mouse models to study the function of MMP-12. Silencing MMP-12 in CRPC cells disrupted lipid utilization and autophagy marker expression via the CD36/CPT1 and P62/LC3 pathways, respectively, leading to reduced CRPC cell migration and invasion. Moreover, animal experiments confirmed that MMP-12-knockdown CRPC xenograft tumors exhibited reduced tumor growth, and the mechanisms involved the promotion of cancer cell autophagy and the inhibition of lipid catabolism. According to our results, MMP-12 played important roles in the progression of CRPC by disrupting adipocyte maturation and regulating cancer migration and invasion via the modulation of autophagy and lipid catabolism pathways.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Masculino , Animales , Ratones , Humanos , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Lipólisis , Metaloproteinasa 12 de la Matriz/metabolismo , Metaloproteinasa 12 de la Matriz/farmacología , Autofagia , Lípidos , Línea Celular Tumoral , Proliferación Celular
14.
Front Microbiol ; 15: 1370417, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38481793

RESUMEN

Introduction: African swine fever virus (ASFV) is a highly contagious virus that spreads rapidly and has a mortality rate of up to 100% in domestic pigs, leading to significant economic losses in the pig industry. The major capsid protein p72 of ASFV plays a critical role in viral invasion and immune evasion. Methods: In this study, we used yeast two-hybrid screening to identify host proteins interacting with p72 in porcine alveolar macrophages (PAMs) and verified these proteins using confocal microscopy and immunoprecipitation techniques. Results and Discussion: We validated 13 proteins that interact with p72, including CD63, B2M, YTHDF2, FTH1, SHFL, CDK5RAP3, VIM, PELO, TIMP2, PHYH, C1QC, CMAS, and ERCC1. Enrichment analysis and protein-protein interaction network analysis of these interacting proteins revealed their involvement in virus attachment, invasion, replication, assembly, and immune regulation. These findings provide new insights into the function of p72 and valuable information for future research on the interaction between ASFV and host proteins.

15.
Aging (Albany NY) ; 16(5): 4191-4203, 2024 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-38461458

RESUMEN

Glioblastoma is the most common malignant tumor in the central nervous system and its occurrence and development is involved in various molecular abnormalities. C-X-C chemokine ligand 10 (CXCL10), an inflammatory chemokine, has been reported to be related to the pathogenesis of cancer while it has not yet been linked to glioma. Calycosin, a bioactive compound derived from Radix astragali, has demonstrated anticancer properties in several malignancies, including glioma. Nonetheless, its underlying mechanisms are not fully understood. This study explores CXCL10 as a potential therapeutic target for calycosin in the suppression of glioblastoma. We observed that CXCL10 expression correlates positively with glioma malignancy and inversely with patient prognosis, highlighting its potential as a glioblastoma treatment target. Furthermore, we found that calycosin inhibited proliferation, migration, and invasion in U87 and U251 glioma cells, and decreased CXCL10 expression in a dose-dependent manner, along with its downstream effectors such as NLRP3, NF-κB, and IL-1ß. Additionally, molecular docking experiments demonstrated that calycosin exhibits a notable binding affinity to CXCL10. Overexpression of CXCL10 counteracted the inhibitory effects of calycosin on cell proliferation, migration, and invasion, while CXCL10 knockdown enhanced these effects. Finally, we verified that calycosin inhibited glioma growth in a xenograft mouse model and downregulated CXCL10 and its downstream molecules. These findings suggest that targeting CXCL10 may be an effective strategy in glioblastoma treatment, and calycosin emerges as a potential therapeutic agent.


Asunto(s)
Glioblastoma , Glioma , Isoflavonas , Humanos , Ratones , Animales , Glioblastoma/patología , Simulación del Acoplamiento Molecular , Ligandos , Línea Celular Tumoral , Glioma/patología , Proliferación Celular , Modelos Animales de Enfermedad , Transducción de Señal , Movimiento Celular , Quimiocina CXCL10/genética
16.
J Biomed Mater Res A ; 112(9): 1565-1577, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38514993

RESUMEN

Polyether ether ketone (PEEK) is gaining recognition as a highly promising polymer for orthopedic implants, attributed to its exceptional biocompatibility, ease of processing, and radiation resistance. However, its long-term in vivo application faces challenges, primarily due to suboptimal osseointegration from postimplantation inflammation and immune reactions. Consequently, biofunctionalization of PEEK implant surfaces emerges as a strategic approach to enhance osseointegration and increase the overall success rates of these implants. In our research, we engineered a multifaceted PEEK implant through the in situ integration of chitosan-coated zinc-doped bioactive glass nanoparticles (Zn-BGNs). This novel fabrication imbues the implant with immunomodulatory capabilities while bolstering its osseointegration potential. The biofunctionalized PEEK composite elicited several advantageous responses; it facilitated M2 macrophage polarization, curtailed the production of inflammatory mediators, and augmented the osteogenic differentiation of bone marrow mesenchymal stem cells. The experimental findings underscore the vital and intricate role of biofunctionalized PEEK implants in preserving normal bone immunity and metabolism. This study posits that utilizing chitosan-BGNs represents a direct and effective method for creating multifunctional implants. These implants are designed to facilitate biomineralization and immunomodulation, making them especially apt for orthopedic applications.


Asunto(s)
Benzofenonas , Regeneración Ósea , Cetonas , Células Madre Mesenquimatosas , Polietilenglicoles , Polímeros , Zinc , Polímeros/química , Polietilenglicoles/química , Regeneración Ósea/efectos de los fármacos , Animales , Cetonas/química , Cetonas/farmacología , Zinc/química , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Ratones , Quitosano/química , Osteogénesis/efectos de los fármacos , Vidrio/química , Células RAW 264.7 , Diferenciación Celular/efectos de los fármacos , Nanopartículas/química
17.
Int J Biol Macromol ; 266(Pt 1): 130939, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38493816

RESUMEN

African swine fever (ASF) is an acute, febrile, highly contagious infection of pigs caused by the African swine fever virus (ASFV). The purpose of this study is to understand the molecular mechanism of ASFV infection and evaluate the effect of DCA on MAPK pathway, so as to provide scientific basis for the development of new antiviral drugs. The transcriptome analysis found that ASFV infection up-regulated the IL-17 and MAPK signaling pathways to facilitate viral replication. Metabolome analysis showed that DCA levels were up-regulated after ASFV infection, and that exogenous DCA could inhibit activation of the MAPK pathway by ASFV infection and thus inhibit viral replication. Dual-luciferase reporter assays were used to screen the genes of ASFV and revealed that I73R could significantly up-regulate the transcription level of AP-1 transcription factor in the MAPK pathway. Confocal microscopy demonstrated that I73R could promote AP-1 entry into the nucleus, and that DCA could inhibit the I73R-mediated nuclear entry of AP-1, inhibiting MAPK pathway, and I73R interacts with AP-1. These results indicated that DCA can inhibit ASFV-mediated activation of the MAPK pathway, thus inhibiting ASFV replication. This study provides a theoretical basis for research on ASF pathogenesis and for antiviral drug development.


Asunto(s)
Virus de la Fiebre Porcina Africana , Ácido Desoxicólico , Sistema de Señalización de MAP Quinasas , Replicación Viral , Replicación Viral/efectos de los fármacos , Animales , Virus de la Fiebre Porcina Africana/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Porcinos , Ácido Desoxicólico/farmacología , Factor de Transcripción AP-1/metabolismo , Chlorocebus aethiops , Células Vero , Fiebre Porcina Africana/virología , Fiebre Porcina Africana/metabolismo , Antivirales/farmacología
18.
J Adv Res ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38382594

RESUMEN

INTRODUCTION: Global warming augments the risk of adverse pregnancy outcomes in vulnerable expectant mothers. Pioneering investigations into heat stress (HS) have predominantly centered on its direct impact on reproductive functions, while the potential roles of gut microbiota, despite its significant influence on distant tissues, remain largely unexplored. Our understanding of deleterious mechanisms of HS and the development of effective intervention strategies to mitigate the detrimental impacts are still limited. OBJECTIVES: In this study, we aimed to explore the mechanisms by which melatonin targets gut microbes to alleviate HS-induced reproductive impairment. METHODS: We firstly evaluated the alleviating effects of melatonin supplementation on HS-induced reproductive disorder in pregnant mice. Microbial elimination and fecal microbiota transplantation (FMT) experiments were then conducted to confirm the efficacy of melatonin through regulating gut microbiota. Finally, a lipopolysaccharide (LPS)-challenged experiment was performed to verify the mechanism by which melatonin alleviates HS-induced reproductive impairment. RESULTS: Melatonin supplementation reinstated gut microbiota in heat stressed pregnant mice, reducing LPS-producing bacteria (Aliivibrio) and increasing beneficial butyrate-producing microflora (Butyricimonas). This restoration corresponded to decreased LPS along the maternal gut-placenta-fetus axis, accompanied by enhanced intestinal and placental barrier integrity, safeguarding fetuses from oxidative stress and inflammation, and ultimately improving fetal weight. Further pseudo-sterile and fecal microbiota transplantation trials confirmed that the protective effect of melatonin on fetal intrauterine growth under HS was partially dependent on gut microbiota. In LPS-challenged pregnant mice, melatonin administration mitigated placental barrier injury and abnormal angiogenesis via the inactivation of the TLR4/MAPK/VEGF signaling pathway, ultimately leading to enhanced nutrient transportation in the placenta and thereby improving the fetal weight. CONCLUSION: Melatonin alleviates HS-induced low fetal weight during pregnancy via the gut-placenta-fetus axis, the first time highlighting the gut microbiota as a novel intervention target to mitigate the detrimental impact of global temperature rise on vulnerable populations.

19.
Braz. j. med. biol. res ; 57: e13351, fev.2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1550147

RESUMEN

Abstract The complex pathogenesis of castration-resistant prostate cancer (CRPC) makes it challenging to identify effective treatment methods. Matrix metalloproteinase (MMP)-12 can degrade elastin as well as various extracellular matrix (ECM) components, which is associated with cancer progression. However, the relationship between MMP-12 and CRPC progression is poorly understood. In this study, we observed the effect of MMP-12 on the progression of CRPC and further explored its potential mechanism of action. High levels of MMP-12 were observed in patients with CRPC. We therefore developed cell co-culture and mouse models to study the function of MMP-12. Silencing MMP-12 in CRPC cells disrupted lipid utilization and autophagy marker expression via the CD36/CPT1 and P62/LC3 pathways, respectively, leading to reduced CRPC cell migration and invasion. Moreover, animal experiments confirmed that MMP-12-knockdown CRPC xenograft tumors exhibited reduced tumor growth, and the mechanisms involved the promotion of cancer cell autophagy and the inhibition of lipid catabolism. According to our results, MMP-12 played important roles in the progression of CRPC by disrupting adipocyte maturation and regulating cancer migration and invasion via the modulation of autophagy and lipid catabolism pathways.

20.
Adv Sci (Weinh) ; 11(13): e2304834, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38269856

RESUMEN

Architected materials design across orders of magnitude length scale intrigues exceptional mechanical responses nonexistent in their natural bulk state. However, the so-termed mechanical metamaterials, when scaling bottom down to the atomistic or microparticle level, remain largely unexplored and conventionally fall out of their coarse-resolution, ordered-pattern design space. Here, combining high-throughput molecular dynamics (MD) simulations and machine learning (ML) strategies, some intriguing atomistic families of disordered mechanical metamaterials are discovered, as fabricated by melt quenching and exemplified herein by lightweight-yet-stiff cellular materials featuring a theoretical limit of linear stiffness-density scaling, whose structural disorder-rather than order-is key to reduce the scaling exponent and is simply controlled by the bonding interactions and their directionality that enable flexible tunability experimentally. Importantly, a systematic navigation in the forcefield landscape reveals that, in-between directional and non-directional bonding such as covalent and ionic bonds, modest bond directionality is most likely to promotes disordered packing of polyhedral, stretching-dominated structures responsible for the formation of metamaterials. This work pioneers a bottom-down atomistic scheme to design mechanical metamaterials formatted disorderly, unlocking a largely untapped field in leveraging structural disorder in devising metamaterials atomistically and, potentially, generic to conventional upscaled designs.

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