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1.
J Cancer ; 15(10): 2971-2980, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706916

RESUMO

BACKGROUND: Meta analysis was adopted to investigate the correlation between messenger ribonucleic acid (mRNA) expression and clinicopathological features of breast cancer (BC). METHODS: English databases, PubMed, Web of Science, Embase, and The Cochrane Library, etc., were searched using a computer. The time range of retrieval was set to be from the establishment of the database to December 2023. The search terms were set as "mRNA", "Breast cancer", "Pathology", "Clinicopathological characteristics", etc. The literatures were screened in line with the inclusion and exclusion criteria, and the data was extracted for analysis by Revman5.3. RESULTS: Finally, 5 suitable included literatures were selected, including 969 patients. The analysis results were found to reveal a significant association between mRNA expression and BC grading (OR = 0.11, 95% CI = 0.04-0.30, Z = 4.26, P<0.0001); a significant correlation was observed between mRNA expression and BC staging (OR = 0.19, 95% CI = 0.05-0.65, Z = 2.65, P = 0.008<0.05); no correlation was found between mRNA expression and menstrual status of BC patients (OR = 0.63, 95% CI = 0.22-1.78, Z = 0.88, P = 0.38>0.05); a correlation was identified between mRNA expression and tumor size in BC (OR = 0.48, 95% CI = 0.24-0.99, Z = 2.00, P = 0.05). In the Discussion section, this study, comprising 10 research studies, aimed to explore the correlation between messenger ribonucleic acid and the clinical pathological features of BC. staging and grading of BC, a certain correlation with tumor size, and no correlation with the menstrual status of BC patients.

2.
Int J Biol Macromol ; 268(Pt 1): 131695, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642684

RESUMO

Due to the absence of effective vaccine and treatment, African swine fever virus (ASFV) control is entirely dependent on accurate and early diagnosis, along with culling of infected pigs. The B646L/p72 is the major capsid protein of ASFV and is an important target for developing a diagnostic assays and vaccines. Herein, we generated a monoclonal antibody (mAb) (designated as 2F11) against the trimeric p72 protein, and a blocking ELISA (bELISA) was established for the detection of both genotype I and II ASFV antibodies. To evaluate the performance of the diagnostic test, a total of 506 porcine serum samples were tested. The average value of percent of inhibition (PI) of 133 negative pig serum was 8.4 % with standard deviation (SD) 6.5 %. Accordingly, the cut-off value of the newly established method was set at 28 % (mean + 3SD). Similarly, a receiver operating characteristic (ROC) was applied to determine the cut off value and the p72-bELISA exhibited a sensitivity of 100 % and a specificity of 99.33 % when the detection threshold was set at 28 %. The bELISA was also able to specifically recognize anti-ASFV sera without cross-reacting with other positive serums for other major swine pathogens. Moreover, by designing a series of overlapped p72 truncated proteins, the linear B cell epitope recognized by 2F11 mAb was defined to be 283NSHNIQ288. Amino acid sequence comparison revealed that the amino acid sequence 283NSHNIQ288 is highly conserved between different ASFV isolates. Our findings indicate that the newly established mAb based blocking ELISA may have a great potential in improving the detection of ASFV antibodies and provides solid foundation for further studies.

3.
Int J Biometeorol ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625430

RESUMO

Fine particulate matter (PM2.5) is a risk factor of cardiovascular disease. Associations between PM2.5 compositions and cardiovascular disease are a point of special interest but inconsistent. This study aimed to explore the cardiovascular effects of heavy metal(loid) compositions in PM2.5. Data for mortality, air pollutants and meteorological factors in Anyang, China from 2017 to 2021 were collected. Heavy metal(loid) in PM2.5 were monitored and examined monthly. A Case-crossover design was applied to the estimated data set. The interquartile range increase in cadmium (Cd), antimony (Sb) and arsenic (As) at lag 1 was associated with increment of 8.1% (95% CI: 3.3, 13.2), 4.8% (95% CI: 0.2, 9.5) and 3.5% (95% CI: 1.1, 6.0) cardiovascular mortality. Selenium in lag 2 was inversely associated with cerebrovascular mortality (RR = 0.920 95% CI: 0.862, 0.983). Current-day exposure of aluminum was positively associated with mortality from ischemic heart disease (RR = 1.083 95% CI: 1.001, 1.172). Stratified analysis indicated sex, age and season modified the cardiovascular effects of As (P < 0.05). Our study reveals that heavy metal(loid) play key roles in adverse effects of PM2.5. Cd, Sb and As were significant risk factors of cardiovascular mortality. These findings have potential implications for accurate air pollutants control and management to improve public health benefits.

4.
Huan Jing Ke Xue ; 45(5): 3069-3077, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629567

RESUMO

Microplastic pollution in the soil environment has received extensive attention, but the effects of different land use patterns on the sub-watershed scale on soil microplastic pollution are poorly understood. The Luoshijiang sub-watershed in the north of Erhai Lake was selected as the research object, and the characteristics of microplastic pollution in farmland, riparian zone, grassland, and woodland soils were analyzed. The pollution risks of microplastics in the four types of soil were assessed using the polymer risk index method, and the effects of land use patterns on the distribution and risk of microplastic pollution were further explored. The results showed that:① The abundance of microplastics in the soil of the Luoshijiang sub-watershed ranged from 220 to 1 900 n·kg-1, and the average abundance was (711 ± 55) n·kg-1. The main polymer types were polyester (PES, 32.52%) and polyethylene terephthalate (PET, 21.95%). The particle size of microplastics was concentrated in the range of 0.5-2 mm (61.89%). Fiber was the main shape of microplastics (>75%), and the dominant color was transparent (58.50%). ② Land use patterns determined the abundance and pollution characteristics of soil microplastics in the Luoshijiang sub-watershed. A significantly higher abundance of microplastics was found in the soil of farmland[(885 ± 95) n·kg-1] and riparian zone[(837 ± 155) n·kg-1], which had stronger intensities of human activity, than that in woodland soil[(491 ± 53) n·kg-1] (P<0.05). Film and fragment microplastics mainly occurred in farmland soil, which also had the largest number of polymer types and the most abundant colors. ③ The risk index level of microplastics (Level Ⅲ) in the soil of farmland was higher than that of the other three land use patterns (Level Ⅰ). This research indicated that the higher the intensity of human activities of a sub-watershed was, the more complex the occurrence characteristics of soil microplastics, the richer the types of polymers, and the higher the potential pollution risks would be. Therefore, it is necessary to strengthen the control of soil microplastic pollution in farmland.

5.
Mol Cancer Ther ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592383

RESUMO

Aurora kinase inhibitors such as alisertib can destabilize MYC-family oncoproteins and have demonstrated compelling anti-tumor efficacy. In this study, we report 6K465, a novel pyrimidine-based Aurora A (AURKA) inhibitor that reduces levels of c-MYC and N-MYC oncoproteins more potently than alisertib. In an analysis of the antiproliferative effect of 6K465, the sensitivities of small cell lung cancer (SCLC) and breast cancer (BC) cell lines to 6K465 were strongly associated with the protein levels of c-MYC and/or N-MYC. We also report DBPR728, an acyl-based prodrug of 6K465 bearing fewer hydrogen-bond donors that exhibited 10-fold improved oral bioavailability. DBPR728 induced durable tumor regression of c-MYC- and/or N-MYC- overexpressing xenografts including SCLC, triple-negative breast cancer (TNBC), hepatocellular carcinoma and medulloblastoma using a 5-on-2-off or once-a-week dosing regimen on a 21-day cycle. A single oral dose of DBPR728 at 300 mg/kg induced c-MYC reduction and cell apoptosis in the tumor xenografts for more than 7 days. The inhibitory effect of DBPR728 at a reduced dosing frequency was attributed to its uniquely high tumor/plasma ratio (3.6-fold within 7 days) and the long tumor half-life of active moiety 6K465. Furthermore, DBPR728 was found to synergize with the mTOR inhibitor everolimus to suppress c-MYC- or N-MYC- driven SCLC. Collectively, these results suggest DBPR728 has the potential to treat cancers overexpressing c-MYC- and/or N-MYC.

6.
ACS Chem Neurosci ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634698

RESUMO

Neuronal death resulting from ischemic stroke is the primary cause of adult mortality and disability, and effective neuroprotective agents for poststroke intervention are still lacking. Remote ischemic postconditioning (RIPostC) has demonstrated significant protective effects against ischemia in various organs; however, the specific mechanisms are not fully understood. This study investigated the potential neuroprotective mechanisms of RIPostC in the context of ischemic stroke. Using a rat model of middle cerebral artery occlusion, we found that RIPostC mitigated neurological damage, improved movement in the open-field test, and protected against neuronal apoptosis. In terms of energy metabolism, RIPostC enhanced ATP levels, suppressed lactate content, and increased the production of ketone bodies (KBs). In the ferroptosis assay, RIPostC protected against lipoperoxidation, reversed the reduction of glutathione peroxidase 4 (GPX4), and mitigated the excessive expression of long-chain acyl-CoA synthetase family member 4 (ACSL4). In oxygen-glucose deprivation/reoxygenation-treated HT22 cells, KBs maintained GPX4 levels, suppressed ACSL4 expression, and preserved the mitochondrial cristae number. However, the effect of KBs on the expression of GPX4, ACSL4, and the number of mitochondrial cristae was blocked by erastin. Moreover, both RIPostC and KBs reduced total iron and ferrous ion content by repressing iron transporters both in vitro and in vivo. In conclusion, KBs-induced mitigation of ferroptosis could represent a new therapeutic mechanism for RIPostC in treating stroke.

7.
Arch Oral Biol ; 163: 105982, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38678878

RESUMO

OBJECTIVES: To investigate the importance of fatty acid oxidation (FAO)-related genes in predicting the progression and prognosis of head and neck squamous cell carcinoma (HNSCC). METHODS: The FAO-related gene prognostic model was established employing Cox regression analyses, during which accuracy and sensitivity of the gene model were evaluated in The Cancer Genome Atlas (TCGA) internal testing and Gene Expression Omnibus (GEO) external validation cohorts. Ultimately, hub genes were identified among 13 model genes using STRING and Cytoscape, with preliminary validation carried out through immunohistochemistry. RESULTS: The model, which comprised 13 genes (ABCD2, ACAA1, ACACB, AKT1, CNR1, CPT1C, CROT, ECHDC2, ETFA, HADHB, IRS2, LONP2, and SLC25A17), was established. On the basis of the median risk score, the two cohorts were grouped into low-and high-risk groups in the subsequent test and validation, and the former exhibited significantly higher survival rates than the latter. Nomograms were established based on prognostic factors, including stage and risk score, and individualized for the prediction of HNSCC patients. Ultimately, immunohistochemical staining showed that ACAA1 and HADHB were significantly under-expressed in HNSCC, with a favorable prognosis associated with low HADHB and high ACAA1. CONCLUSIONS: The gene prognostic model has illustrated promising capability in predicting the prognosis, and ACAA1 and HADHB might serve as potential therapeutic biomarkers for HNSCC patients.


Assuntos
Biomarcadores Tumorais , Ácidos Graxos , Neoplasias de Cabeça e Pescoço , Nomogramas , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Estudos Retrospectivos , Prognóstico , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Masculino , Ácidos Graxos/metabolismo , Feminino , Pessoa de Meia-Idade , Oxirredução , Imuno-Histoquímica , Idoso , Regulação Neoplásica da Expressão Gênica
8.
Chin J Dent Res ; 27(1): 101-109, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546525

RESUMO

OBJECTIVE: To explore potential pathogenic processes and possible treatments using unbiased and reliable bioinformatic tools. METHODS: Gene expression profiles of control and hepatocyte growth factor (HGF) samples were downloaded from CNP0000995. Analysis of differentially expressed genes (DEGs) was conducted using R software (version 4.2.1, R Foundation, Vienna, Austria). Functional enrichment analyses were performed using the Gene Ontology (GO), Kyoto Encyclopaedia of Genes and Genomes (KEGG) and Gene Set Enrichment Analysis (GSEA) databases, then the proteinprotein interaction (PPI) network was constructed to screen the top 10 hub genes. Finally, five genes related to cell junctions were selected to build gene-miRNA interactions and predict small-molecule drugs. RESULTS: A total of 342 downregulated genes and 188 upregulated genes were detected. Candidate pathways include the extracellular matrix (ECM) receptor interaction pathway, the TGF-ß signalling pathway and the cell adhesion molecule (CAM) pathway, which were discovered through KEGG and GSEA enrichment studies. GO analyses revealed that these DEGs were significantly enriched in cell adhesion, the adherens junction and focal adhesion. Five hub genes (CDH1, SNAP25, RAC2, APOE and ITGB4) associated with cell adhesion were identified through PPI analysis. Finally, the gene-miRNA regulatory network identified three target miRNAs: hsa-miR-7110-5p, hsa-miR-149-3p and hsa-miR-1207-5p. Based on the gene expression profile, the small-molecule drugs zebularine, ecuronium and prostratin were selected for their demonstrated binding activity when docked with the mentioned molecules. CONCLUSION: This study offered some novel insights into molecular pathways and identified five hub genes associated with cell adhesion. Based on these hub genes, three potential therapeutic miRNAs and small-molecule drugs were predicted, which are expected to provide guidance for the treatment of patients with HGF.


Assuntos
Fibromatose Gengival , MicroRNAs , Humanos , MicroRNAs/genética , Adesão Celular , Adesões Focais
9.
Int Immunopharmacol ; 130: 111786, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38447415

RESUMO

G-protein coupled receptors (GPCRs) constitute the largest class of cell surface receptors and present prominent drug targets. GPR139 is an orphan GPCR detected in the septum of the brain. However, its roles in cognition are still unclear. Here we first established a mouse model of cognitive impairment by a single intracerebroventricular injection of aggregated amyloid-beta peptide 1-42 (Aß1-42). RNA-sequencing data analysis showed that Aß1-42 induced a significant decrease of GPR139 mRNA in the basal forebrain. Using GPR139 agonist JNJ-63533054 and behavioral tests, we found that GPR139 activation in the brain ameliorated Aß1-42-induced cognitive impairment. Using western blot, TUNEL apoptosis and Golgi staining assays, we showed that GPR139 activation alleviated Aß1-42-induced apoptosis and synaptotoxicity in the basal forebrain rather than prefrontal cortex and hippocampus. The further study identified that GPR139 was widely expressed in cholinergic neurons of the medial septum (MS). Using the overexpression virus and transgenic animal model, we showed that up-regulation of GPR139 in MS cholinergic neurons ameliorated cognitive impairment, apoptosis and synaptotoxicity in APP/PS1 transgenic mice. These findings reveal that GPR139 of MS cholinergic neurons could be a critical node in cognition and potentially provides insight into the pathogenesis of Alzheimer's disease.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Proteínas do Tecido Nervoso , Receptores Acoplados a Proteínas G , Septo do Cérebro , Animais , Camundongos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Camundongos Transgênicos , Regulação para Cima , Proteínas do Tecido Nervoso/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Septo do Cérebro/metabolismo , Camundongos Endogâmicos C57BL
10.
Sci Total Environ ; 924: 171703, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38490424

RESUMO

Healthcare-associated infections (HAIs) pose significant risks to pediatric patients in outpatient settings. To prevent HAIs, understanding the sources and transmission routes of pathogenic microorganisms is crucial. This study aimed to identify the sources of opportunistic bacterial pathogens (OBPs) in pediatric outpatient settings and determine their transmission routes. Furthermore, assessing the public health risks associated with the core OBPs is important. We collected 310 samples from various sites in pediatric outpatient areas and quantified the bacteria using qPCR and CFU counting. We also performed 16S rRNA gene and single-bacterial whole-genome sequencing to profile the transmission routes and antibiotic resistance characteristics of OBPs. We observed significant variations in microbial diversity and composition among sampling sites in pediatric outpatient settings, with active communication of the microbiota between linked areas. We found that the primary source of OBPs in multi-person contact areas was the hand surface, particularly in pediatric patients. Five core OBPs, Staphylococcus epidermidis, Acinetobacter baumannii, Pseudomonas aeruginosa, Streptococcus mitis, and Streptococcus oralis, were mainly derived from pediatric patients and spread into the environment. These OBPs accumulated at multi-person contact sites, resulting in high microbial diversity in these areas. Transmission tests confirmed the challenging spread of these pathogens, with S. epidermidis transferring from the patient's hand to the environment, leading to an increased abundance and emergence of related strains. More importantly, S. epidermidis isolated from pediatric patients carried more antibiotic-resistance genes. In addition, two strains of multidrug-resistant A. baumannii were isolated from both a child and a parent, confirming the transmission of the five core OBPs centered around pediatric patients and multi-person contact areas. Our results demonstrate that pediatric patients serve as a significant source of OBPs in pediatric outpatient settings. OBPs carried by pediatric patients pose a high public health risk. To effectively control HAIs, increasing hand hygiene measures in pediatric patients and enhancing the frequency of disinfection in multi-person contact areas remains crucial. By targeting these preventive measures, the spread of OBPs can be reduced, thereby mitigating the risk of HAIs in pediatric outpatient settings.


Assuntos
Antibacterianos , Infecção Hospitalar , Humanos , Criança , RNA Ribossômico 16S , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Staphylococcus epidermidis , Saúde Pública , Testes de Sensibilidade Microbiana
11.
Plant Physiol ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466216

RESUMO

Soil (or plant) water deficit accelerates plant reproduction. However, the underpinning molecular mechanisms remain unknown. By modulating cell division/number, ABSCISIC ACID-INSENSITIVE 5 (ABI5), a key bZIP (basic (region) leucine zippers) transcription factor, regulates both seed development and abiotic stress responses. The KRP (KIP-RELATED PROTEIN) cyclin-dependent kinases (CDKs) play an essential role in controlling cell division, and SHOOT MERISTEMLESS (STM) plays a key role in the specification of flower meristem identity. Here, our findings show that abscisic acid (ABA) signaling and/or metabolism in adjust reproductive outputs (such as rosette leaf number and open flower number) under water-deficient conditions in Arabidopsis (Arabidopsis thaliana) plants. Reproductive outputs increased under water-sufficient conditions but decreased under water-deficient conditions in the ABA signaling/metabolism mutants abscisic acid2-1 (aba2-1), aba2-11, abscisic acid insensitive3-1 (abi3-1), abi4-1, abi5-7, and abi5-8. Further, under water-deficient conditions, ABA induced-ABI5 directly bound to the promoter of KRP1, which encodes a CDK that plays an essential role in controlling cell division, and this binding subsequently activated KRP1 expression. In turn, KRP1 physically interacted with SHOOT MERISTEMLESS (STM), which functions in the specification of flower meristem identity, promoting STM degradation. We further demonstrate that reproductive outputs are adjusted by the ABI5-KRP1-STM molecular module under water-deficient conditions. Together, our findings reveal the molecular mechanism by which ABA signaling and/or metabolism regulate reproductive development under water-deficient conditions. These findings provide insights that may help guide crop yield improvement under water deficiency.

12.
Front Psychol ; 15: 1265047, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38323156

RESUMO

Introduction: Due to the limitations of traditional didactic teaching, inquiry-based teaching has attracted increasing attention and has become an important content of curriculum teaching reform in college education. Nevertheless, it is vital to investigate students' subjective acceptance of inquiry-based instruction and its influencing factors before inquiry-based teaching methods are widely implemented. Methods: In light of this, taking into account the psychological factors of students, an acceptance model of inquiry-based teaching pedagogy was established based on the extended technology acceptance model (TAM). Three additional variables, namely self-efficacy, implementation quality, and risk perception, were incorporated into the TAM. Firstly, subjective evaluation data of the influencing factors of inquiry teaching acceptance were obtained through a network questionnaire survey from university students in Guangdong, China, using snowball sampling and convenient sampling. A total of 485 valid questionnaires were retrieved, with an effective response rate of 88.2%. Then, internal consistency and reliability, convergent validity and discriminant validity of the model and its hypothesis were tested with reliability and validity tests. Finally, path analysis was used to examine key determinants of students' acceptance of inquiry teaching and moderators. Results: Results indicated that the constructed model can explain the acceptability of inquiry teaching for college students by 88.6%; Attitude has a positive significant impact on behavioral intention; Perceived ease of use indirectly affects behavioral intention through perceived usefulness, while perceived usefulness indirectly affects behavioral intention through attitude; self-efficacy not only directly affects behavioral intention but also indirectly affects behavioral intention through implementation quality; implementation quality indirectly affects behavioral intention through perceived usefulness and attitude; students' risk perception of inquiry-based teaching has no negative impact on behavioral intention. Conclusion: Overall, this study has implications for policymakers, teachers or learners in terms of the implementation and promotion of inquiry-based teaching in college classroom.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38412702

RESUMO

This study compares the skin structures of Rana kukunoris with two different skin colors living in the same area of Haibei in the Northeastern Qinghai-Tibet Plateau. The skin thickness of the khaki R. kukunoris was significantly greater than that of the brown R. kukunoris (P < 0.01), and significantly more mucous and granular glands were present on the dorsal skin of the khaki frog (P < 0.05). Meanwhile, the melanocytes on the dorsal skin of the brown frog were significantly larger than those on the khaki one (P < 0.05). Morphological changes in the expansion and aggregation of melanocytes seemed to deepen the skin color of R. kukunoris. Moreover, transcriptome sequencing identified tyrosine metabolism, melanogenesis, and riboflavin metabolism as the main pathways involved in melanin formation and metabolism in brown R. kukunoris. TYR, MC1R was upregulated as the skin color of R. kukunoris was deepened and contributed to melanin production and metabolism. In contrast, the khaki frog had significantly more upregulated genes and metabolic pathways related to autoimmunity. The khaki frog appeared to defend against ultraviolet (UV) radiation-induced damage by secreting mucus and small molecular peptides, whereas the brown frog protected itself by distributing a large amount of melanin. Hence, the different skin colors of R. kukunoris might represent different adaptation strategies for survival in the intense UV radiation environment of the Qinghai-Tibet Plateau.

14.
Molecules ; 29(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38398608

RESUMO

Lipoteichoic acid (LTA) plays an essential role in bacterial growth and resistance to antibiotics, and LTA synthetase (LtaS) was considered as an attractive target for combating Gram-positive infections. Azalomycin F, a natural guanidyl-containing polyhydroxy macrolide, can target the LTA of Staphylococcus aureus. Using various technologies including enzyme-linked immunosorbent assay, transmission electron microscope, proteomics, and parallel reaction monitoring, here, the experimental results indicated that azalomycin F can accelerate the LTA release and disrupt the cell envelope, which would also lead to the feedback upregulation on the expressions of LtaS and other related enzymes. Simultaneously, the reconstituted enzyme activity evaluations showed that azalomycin F can significantly inhibit the extracellular catalytic domain of LtaS (eLtaS), while this was vague for LtaS embedded in the liposomes. Subsequently, the fluorescence analyses for five incubation systems containing azalomycin F and eLtaS or the LtaS-embedded liposome indicated that azalomcyin F can spontaneously bind to the active center of LtaS. Combining the mass spectroscopy analyses and the molecular dockings, the results further indicated that this interaction involves the binding sites of substrates and the LTA prolongation, especially the residues Lys299, Phe353, Trp354 and His416. All these suggested that azalomycin F has multiple antibacterial mechanisms against S. aureus. It can not only inhibit LTA biosynthesis through the interactions of its guanidyl side chain with the active center of LtaS but also disrupt the cell envelope through the synergistic effect of accelerating the LTA release, damaging the cell membrane, and electrostatically interacting with LTA. Simultaneously, these antibacterial mechanisms exhibit a synergistic inhibition effect on S. aureus cells, which would eventually cause the cellular autolysis.


Assuntos
Lipopolissacarídeos , Staphylococcus aureus , Lipopolissacarídeos/metabolismo , Membrana Celular/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Ácidos Teicoicos , Macrolídeos/farmacologia
15.
Mol Oncol ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381121

RESUMO

Prostate stromal cells play a crucial role in the promotion of tumor growth and immune evasion in the tumor microenvironment (TME) through intricate molecular alterations in their interaction with prostate cancer (PCa) cells. While the impact of these cells on establishing an immunosuppressive response and influencing PCa aggressiveness remains incompletely understood. Our study shows that the activation of the leukemia inhibitory factor (LIF)/LIF receptor (LIFR) pathway in both prostate tumor and stromal cells, following androgen deprivation therapy (ADT), leads to the development of an immunosuppressive TME. Activation of LIF/LIFR signaling in PCa cells induces neuroendocrine differentiation (NED) and upregulates immune checkpoint expression. Inhibition of LIF/LIFR attenuates these effects, underscoring the crucial role of LIF/LIFR in linking NED to immunosuppression. Prostate stromal cells expressing LIFR contribute to NED and immunosuppressive marker abundance in PCa cells, while LIFR knockdown in prostate stromal cells reverses these effects. ADT-driven LIF/LIFR signaling induces brain-derived neurotrophic factor (BDNF) expression, which, in turn, promotes NED, aggressiveness, and immune evasion in PCa cells. Clinical analyses demonstrate elevated BDNF levels in metastatic castration-resistant PCa (CRPC) and a positive correlation with programmed death-ligand 1 (PDL1) and immunosuppressive signatures. This study shows that the crosstalk between PCa cells and prostate stromal cells enhances LIF/LIFR signaling, contributing to an immunosuppressive TME and NED in PCa cells through the upregulation of BDNF.

16.
ChemSusChem ; : e202301508, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280139

RESUMO

Hole mobility is critical to the power conversion efficiencies of perovskite solar cells (PSCs). Organic small-molecule hole-transporting materials (HTMs) have attracted considerable interest in PSCs due to their structural flexibility and operational durability, but they suffer from modest hole mobility. On the other hand, inorganic HTMs with good hole mobility are inflexible in structural variation and exhibit unsatisfactory cell efficiency. In this study, a ligand BT28 and its zinc-based coordination complex BTZ30 were synthesized, characterized, and investigated as HTMs for PSC applications. The mixed-halide perovskites can be grown uniformly with large crystalline grains on both HTMs, which exhibit similar optical and electrochemical properties. However, it was discovered that the BTZ30-based solar cell exhibited an open-circuit voltage of 1.0817 V and a high short-circuit current density of 23.1392 mA cm-2 with a champion power conversion efficiency of close to 20 %. The performance difference between the two HTMs can be attributed to the difference in their hole mobilities, which is 63.31 % higher for BTZ30 than BT28. The comparison of non-metal and metal HTMs revealed the importance of considering hybrid structures to overcome some shortcomings associated with organic and inorganic HTMs and achieve high-performance PSCs.

17.
19.
Br J Math Stat Psychol ; 77(2): 316-336, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38095333

RESUMO

Analysing data from educational tests allows governments to make decisions for improving the quality of life of individuals in a society. One of the key responsibilities of statisticians is to develop models that provide decision-makers with pertinent information about the latent process that educational tests seek to represent. Mixtures of t $$ t $$ factor analysers (MtFA) have emerged as a powerful device for model-based clustering and classification of high-dimensional data containing one or several groups of observations with fatter tails or anomalous outliers. This paper considers an extension of MtFA for robust clustering of censored data, referred to as the MtFAC model, by incorporating external covariates. The enhanced flexibility of including covariates in MtFAC enables cluster-specific multivariate regression analysis of dependent variables with censored responses arising from upper and/or lower detection limits of experimental equipment. An alternating expectation conditional maximization (AECM) algorithm is developed for maximum likelihood estimation of the proposed model. Two simulation experiments are conducted to examine the effectiveness of the techniques presented. Furthermore, the proposed methodology is applied to Peruvian data from the 2007 Early Grade Reading Assessment, and the results obtained from the analysis provide new insights regarding the reading skills of Peruvian students.


Assuntos
Algoritmos , Qualidade de Vida , Humanos , Funções Verossimilhança , Peru , Análise Multivariada , Simulação por Computador
20.
J Biomol Struct Dyn ; 42(7): 3579-3592, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37288787

RESUMO

Dacomitinib (DAC), as a member of tyrosine kinase inhibitors is primarily used to treat non-small cell lung cancer. The intermolecular interaction between DAC and bovine serum albumin (BSA) was comprehended with the help of experiments and theoretical simulations. The outcomes indicated that DAC quenched the endogenous fluorescence of BSA through static quenching mode. In the binding process, DAC was preferentially inserted into the hydrophobic cavity of BSA subdomain IA (site III), and a fluorescence-free DAC-BSA complex with molar ratio of 1:1 was generated. The outcomes confirmed that DAC had a stronger affinity on BSA and the non-radiative energy transfer occurred in the combination process of two. And, it can be inferred from the outcomes of thermodynamic parameters and competition experiments with 8-aniline-1-naphthalenesulfonic acid (ANS) and D-(+)- sucrose that hydrogen bonds (H-bonds), van der Waals forces (vdW) and hydrophobic forces had a significant impact in inserting DAC into the hydrophobic cavity of BSA. The outcomes from multi-spectroscopic measurements that DAC could affect the secondary structure of BSA, that was, α-helix content decreased slightly from 51.0% to 49.7%. Moreover, the combination of DAC and BSA led to a reduction in the hydrophobicity of the microenvironment around tyrosine (Tyr) residues in BSA while had little influence on the microenvironment of around tryptophan (Trp) residues. The outcomes from molecular docking and molecular dynamics (MD) simulation further demonstrated the insertion of DAC into site III of BSA and hydrogen energy and van der Waals energy were the dominant energy of DAC-BSA stability. In addition, the influence of metal ions (Fe3+, Cu2+, Co2+, etc.) on the affinity of the system was explored.Communicated by Ramaswamy H. Sarma.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Quinazolinonas , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Termodinâmica , Sítios de Ligação , Espectrofotometria Ultravioleta , Dicroísmo Circular , Microambiente Tumoral
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