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1.
Biomimetics (Basel) ; 9(7)2024 Jul 04.
Article in English | MEDLINE | ID: mdl-39056847

ABSTRACT

The present investigations on tandem wing configurations primarily revolve around the effects of the spacing L and the phase difference φ between the forewing and the hindwing on aerodynamic performance. However, in nature, organisms employing biplane flight, such as dragonflies, demonstrate the ability to achieve superior aerodynamic performance by flexibly adjusting their flapping trajectories. Therefore, this study focuses on the effects of φ, as well as the trajectory of the hindwing, on aerodynamic performance. By summarizing four patterns of wake-wing interaction processes, it is indicated that φ=-90∘ and 0∘ enhances the thrust of the hindwing, while φ=90∘ and 180∘ result in reductions. Furthermore, the wake-wing interactions and shedding modes are summarized corresponding to three kinds of trajectories, including elliptical trajectories, figure-eight trajectories, and double figure-eight trajectories. The results show that the aerodynamic performance of the elliptical trajectory is similar to that of the straight trajectory, while the figure-eight trajectory with positive surging motion significantly enhances the aerodynamic performance of the hindwing. Conversely, the double-figure-eight trajectory degrades the aerodynamic performance of the hindwing.

2.
Biomimetics (Basel) ; 9(7)2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39056874

ABSTRACT

The aerodynamic effects of wing corrugation on insect flight have received widespread attention. However, there has hardly been any specific focus on dynamic changes to corrugation angle in the models. The flexible vein joints containing resilin in the wings of dragonflies and damselflies enable the longitudinal veins to rotate and thereby change the corrugation angles throughout flapping cycles. Therefore, a two-dimensional corrugated airfoil with time-varying corrugation angles is proposed and the aerodynamic performance is evaluated in terms of aerodynamic force, power and efficiency. The results indicate that the airfoil with time-varying corrugations outperforms the rigid one in terms of enhancing thrust and reducing power consumption. The aerodynamic performance of time-varying corrugated airfoils is optimal when the angle varies in a specific range, and an excessively large angle variation may have negative effects. In addition, excessive height or a negative leading edge of the corrugation can lead to a reduction in the thrust. A design concept for the 2D airfoil with time-varying corrugations is provided and the findings are of significance for enhancing the aerodynamic performance of biomimetic flexible flapping-wing vehicles.

3.
Metab Eng ; 85: 35-45, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39019251

ABSTRACT

Colistin, also known as polymyxin E, is a lipopeptide antibiotic used to treat infections caused by multidrug-resistant gram-negative bacteria. It is considered a "last-line antibiotic", but its clinical development is hindered by low titer and impurities resulting from the presence of diverse homologs in microbial fermentation. To ensure consistent pharmaceutical activity and kinetics, it is crucial to have high-purity colistin active pharmaceutical ingredient (API) in the pharmaceutical industry. This study focused on the metabolic engineering of a natural colistin producer strain to produce colistin with a high titer and purity. Guided by genome mining, we identified Paenibacillus polymyxa ATCC 842 as a natural colistin producer capable of generating a high proportion of colistin A. By systematically inactivating seven non-essential biosynthetic gene clusters (BGCs) of peptide metabolites that might compete precursors with colistin or inhibit colistin production, we created an engineered strain, P14, which exhibited an 82% increase in colistin titer and effectively eliminated metabolite impurities such as tridecaptin, paenibacillin, and paenilan. Additionally, we engineered the L-2,4-diaminobutyric acid (L-2,4-DABA) pathway to further enhance colistin production, resulting in the engineered strain P19, which boosted a remarkable colistin titer of 649.3 mg/L - a 269% improvement compared to the original strain. By concurrently feeding L-isoleucine and L-leucine, we successfully produced high-purity colistin A, constituting 88% of the total colistin products. This study highlights the potential of metabolic engineering in improving the titer and purity of lipopeptide antibiotics in the non-model strain, making them more suitable for clinical use. These findings indicate that efficiently producing colistin API in high purity directly from fermentation can now be achieved in a straightforward manner.

4.
Hematology ; 29(1): 2377860, 2024 Dec.
Article in English | MEDLINE | ID: mdl-39007733

ABSTRACT

BACKGROUD: Li-Fraumeni syndrome is a hereditary tumor syndrome characterized by an elevated risk of malignancy, particularly acute lymphoblastic leukemia (ALL), which can be caused by the heterozygous germline mutation. TP53 gene germline mutation is considered a potential risk factor and crucial prognostic parameter for acute leukemia development and diagnosis, but rarely occurs in adults, and its specific pathogenic significance in acute leukemia is unclear. CASE PRESENTATION: We describes a case of a 45-year-old woman diagnosed with ALL. Whole-exome sequencing approach identified one of the TP53 germline mutations from her bone marrow sample with possible pathogenic significance, c.848G>A (p.Arg283His) heterozygous missense mutation located on exon 8, which was further verified in her hair, oral mucous and nail samples. Family pedigree screening revealed that the same TP53 genetic variant was present in the patient's father and non-donor son, whereas not in the donor. Digital PCR observed that this point mutation frequency dropped post-transplantation but remained low during maintenance therapy when the patient was leukemia-free. CONCLUSION: This suspected Li-Fraumeni syndrome case report with a likely pathogenic heterozygous TP53 variant expands the cancer genetic spectrum. Screening her family members for mutations facilitates identifying the optimal relative donor and avoids unnecessary treatment by monitoring TP53 germline mutations for minimal residual disease following hematopoietic stem cell transplantation. Its potential roles in hematological malignant tumor development and clinical pathogenic implications necessitate further probing.


Subject(s)
Germ-Line Mutation , Li-Fraumeni Syndrome , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Tumor Suppressor Protein p53 , Humans , Female , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Middle Aged , Tumor Suppressor Protein p53/genetics , Li-Fraumeni Syndrome/genetics , Li-Fraumeni Syndrome/diagnosis , Pedigree
5.
Transl Vis Sci Technol ; 13(7): 10, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38984914

ABSTRACT

Purpose: The purpose of this study was to establish and validate a deep learning model to screen vascular aging using retinal fundus images. Although vascular aging is considered a novel cardiovascular risk factor, the assessment methods are currently limited and often only available in developed regions. Methods: We used 8865 retinal fundus images and clinical parameters of 4376 patients from two independent datasets for training a deep learning algorithm. The gold standard for vascular aging was defined as a pulse wave velocity ≥1400 cm/s. The probability of the presence of vascular aging was defined as deep learning retinal vascular aging score, the Reti-aging score. We compared the performance of the deep learning model and clinical parameters by calculating the area under the receiver operating characteristics curve (AUC). We recruited clinical specialists, including ophthalmologists and geriatricians, to assess vascular aging in patients using retinal fundus images, aiming to compare the diagnostic performance between deep learning models and clinical specialists. Finally, the potential of Reti-aging score for identifying new-onset hypertension (NH) and new-onset carotid artery plaque (NCP) in the subsequent three years was examined. Results: The Reti-aging score model achieved an AUC of 0.826 (95% confidence interval [CI] = 0.793-0.855) and 0.779 (95% CI = 0.765-0.794) in the internal and external dataset. It showed better performance in predicting vascular aging compared with the prediction with clinical parameters. The average accuracy of ophthalmologists (66.3%) was lower than that of the Reti-aging score model, whereas geriatricians were unable to make predictions based on retinal fundus images. The Reti-aging score was associated with the risk of NH and NCP (P < 0.05). Conclusions: The Reti-aging score model might serve as a novel method to predict vascular aging through analysis of retinal fundus images. Reti-aging score provides a novel indicator to predict new-onset cardiovascular diseases. Translational Relevance: Given the robust performance of our model, it provides a new and reliable method for screening vascular aging, especially in undeveloped areas.


Subject(s)
Aging , Deep Learning , Fundus Oculi , Retinal Vessels , Humans , Female , Aged , Male , Middle Aged , Aging/physiology , Retinal Vessels/diagnostic imaging , Retinal Vessels/pathology , ROC Curve , Pulse Wave Analysis/methods , Risk Factors , Area Under Curve , Aged, 80 and over , Hypertension/physiopathology
6.
Heliyon ; 10(12): e32635, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38975174

ABSTRACT

Intercultural competence has become one of the important goals of foreign language education. The potential and value of foreign language education on students' intercultural competence (IC) has been widely recognized by academia. Currently, most of the research on intercultural foreign language teachers in China focuses on university teachers, with little attention paid to primary school EFL teachers. However, the cultivation of IC is a staged and continuous process which cannot be achieved in one stroke. Therefore, it is necessary to include primary school EFL teachers in the study of IC cultivation. This paper presents data on Chinese primary school EFL teachers' beliefs about incorporating IC into foreign language teaching. Specifically, their understanding of culture, IC, and intercultural teaching practices are investigated through interviews. The interview transcriptions were analyzed using thematic analysis. The research found: 1. Chinese primary school EFL teachers generally hold an essentialist view of culture; 2. Teachers emphasize the attitudinal dimension of IC; however, they also exhibit a tendency to oversimplify IC or perceive it as a higher-order skill than language proficiency, hence deeming it unsuitable for cultivation at the primary school level; 3. Most cultural teaching practices are teacher-centered, focusing on background knowledge-style introduction. In general, teachers' intercultural teaching practices align with their cultural outlook. At last, the study explores two suggestions for promoting intercultural foreign language teaching: 1. Supporting primary school EFL teachers in updating their language and culture concepts system; 2. Encouraging teachers to reflect on their daily teaching practices as a major opportunity to promote the development of intercultural foreign language teaching.

8.
Acad Radiol ; 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38902110

ABSTRACT

RATIONALE AND OBJECTIVES: To investigate the potential of T1-weighted imaging (T1WI)-based hippocampal radiomics as imaging markers for the diagnosis of Alzheimer's disease (AD) and their efficacy in discriminating between mild cognitive impairment (MCI) and dementia in AD. METHODS: A total of 126 AD patients underwent T1WI-based magnetic resonance imaging (MRI) examinations, along with 108 age-sex-matched healthy controls (HC). This was a retrospective, single-center study conducted from November 2021 to February 2023. AD patients were categorized into two groups based on disease progression and cognitive function: AD-MCI and dementia (AD-D). T1WI-based radiomics features of the bilateral hippocampi were extracted. To diagnose AD and differentiate between AD-MCI and AD-D, predictive models were developed using random forest (RF), logistic regression (LR), and support vector machine (SVM). We compared radiomics features between the AD and HC groups, as well as within the subgroups of AD-MCI and AD-D. Area under the curve (AUC), accuracy, sensitivity, and specificity were all used to assess model performance. Furthermore, correlations between radiomics features and Mini-Mental State Examination (MMSE) scores, tau protein phosphorylated at threonine 181 (P-tau-181), and amyloid ß peptide1-42 (Aß1-42) were analyzed. RESULTS: The RF model demonstrated superior performance in distinguishing AD from HC (AUC=0.961, accuracy=90.8%, sensitivity=90.7%, specificity=90.9%) and in identifying AD-MCI and AD-D (AUC=0.875, accuracy=80.7%, sensitivity=87.2%, specificity=73.2%) compared to the other models. Additionally, radiomics features were correlated with MMSE scores, P-tau-181, and Aß1-42 levels in AD. CONCLUSION: T1WI-based hippocampal radiomics features are valuable for diagnosing AD and identifying AD-MCI and AD-D.

9.
Nat Commun ; 15(1): 4901, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38851779

ABSTRACT

Antimicrobial resistance remains a significant global threat, driving up mortality rates worldwide. Ribosomally synthesized and post-translationally modified peptides have emerged as a promising source of novel peptide antibiotics due to their diverse chemical structures. Here, we report the discovery of new aminovinyl-(methyl)cysteine (Avi(Me)Cys)-containing peptide antibiotics through a synergistic approach combining biosynthetic rule-based omics mining and heterologous expression. We first bioinformatically identify 1172 RiPP biosynthetic gene clusters (BGCs) responsible for Avi(Me)Cys-containing peptides formation from a vast pool of over 50,000 bacterial genomes. Subsequently, we successfully establish the connection between three identified BGCs and the biosynthesis of five peptide antibiotics via biosynthetic rule-guided metabolic analysis. Notably, we discover a class V lanthipeptide, massatide A, which displays excellent activity against gram-positive pathogens, including drug-resistant clinical isolates like linezolid-resistant S. aureus and methicillin-resistant S. aureus, with a minimum inhibitory concentration of 0.25 µg/mL. The remarkable performance of massatide A in an animal infection model, coupled with a relatively low risk of resistance and favorable safety profile, positions it as a promising candidate for antibiotic development. Our study highlights the potential of Avi(Me)Cys-containing peptides in expanding the arsenal of antibiotics against multi-drug-resistant bacteria, offering promising drug leads in the ongoing battle against infectious diseases.


Subject(s)
Anti-Bacterial Agents , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/genetics , Peptides, Cyclic/pharmacology , Peptides, Cyclic/chemistry , Humans , Multigene Family , Mice , Antimicrobial Peptides/pharmacology , Antimicrobial Peptides/chemistry , Antimicrobial Peptides/genetics , Antimicrobial Peptides/metabolism , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Drug Resistance, Bacterial/genetics , Drug Resistance, Bacterial/drug effects , Genome, Bacterial/genetics , Staphylococcus aureus/drug effects , Staphylococcus aureus/genetics , Computational Biology/methods , Cysteine/metabolism , Cysteine/chemistry
10.
Int J Hematol ; 120(2): 262-266, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38730189

ABSTRACT

Pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) has been introduced for the mobilization of peripheral blood stem cells (PBSCs). However, no cases of acute lung injury (ALI) in healthy donors have been reported, and the underlying mechanisms remain poorly understood. We first reported a case of ALI caused by PEG-rhG-CSF in a healthy Chinese donor, characterized by hemoptysis, hypoxemia, and patchy shadows. Ultimately, hormone administration, planned PBSC collection, leukocyte debridement, and planned PBSC collection resulted in active control of the donor's ALI. The donor's symptoms improved without any adverse effects, and the PBSC collection proceeded without incident. Over time, the lung lesion was gradually absorbed and eventually returned to normal. PEG-rhG-CSF may contribute to ALI in healthy donors via mechanisms involving neutrophil aggregation, adhesion, and the release of inflammatory mediators in the lung. This case report examines the clinical manifestations, treatment, and mechanism of lung injury induced by PEG-rhG-CSF-mobilized PBSCs.


Subject(s)
Acute Lung Injury , Granulocyte Colony-Stimulating Factor , Hematopoietic Stem Cell Mobilization , Polyethylene Glycols , Recombinant Proteins , Humans , Acute Lung Injury/etiology , Acute Lung Injury/chemically induced , Granulocyte Colony-Stimulating Factor/adverse effects , Granulocyte Colony-Stimulating Factor/administration & dosage , Recombinant Proteins/therapeutic use , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Hematopoietic Stem Cell Mobilization/adverse effects , Hematopoietic Stem Cell Mobilization/methods , Polyethylene Glycols/adverse effects , Male , Adult , Peripheral Blood Stem Cell Transplantation/adverse effects , Peripheral Blood Stem Cells , Tissue Donors , Blood Donors
11.
Heliyon ; 10(9): e30616, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38774083

ABSTRACT

Purpose: The objective of this study was to provide theoretically feasible strategies by understanding the relationship between the immune microenvironment and the diagnosis and prognosis of AML patients. To this end, we built a ceRNA network with lncRNAs as the core and analyzed the related lncRNAs in the immune microenvironment by bioinformatics analysis. Methods: AML transcriptome expression data and immune-related gene sets were obtained from TCGA and ImmPort. Utilizing Pearson correlation analysis, differentially expressed immune-related lncRNAs were identified. Then, the LASSO-Cox regression analysis was performed to generate a risk signature consisting immune-related lncRNAs. Accuracy of signature in predicting patient survival was evaluated using univariate and multivariate analysis. Next, GO and KEGG gene enrichment and ssGSEA were carried out for pathway enrichment analysis of 183 differentially expressed genes, followed by drug sensitivity and immune infiltration analysis with pRRophetic and CIBERSORT, respectively. Cytoscape was used to construct the ceRNA network for these lncRNAs. Results: 816 common lncRNAs were selected to acquire the components related to prognosis. The final risk signature established by multivariate Cox and stepwise regression analysis contained 12 lncRNAs engaged in tumor apoptotic and metastatic processes: LINC02595, HCP5, AC020934.2, AC008770.3, LINC01770, AC092718.4, AL589863.1, AC131097.4, AC012368.1, C1RL-AS1, STARD4-AS1, and AC243960.1. Based on this predictive model, high-risk patients exhibited lower overall survival rates than low-risk patients. Signature lncRNAs showed significant correlation with tumor-infiltrating immune cells. In addition, significant differences in PD-1/PD-L1 expression and bleomycin/paclitaxel sensitivity were observed between risk groups. Conclusion: LncRNAs related to immune microenvironment were prospective prognostic and therapeutic options for AML.

12.
Front Microbiol ; 15: 1290985, 2024.
Article in English | MEDLINE | ID: mdl-38812686

ABSTRACT

Introduction: Allergic rhinitis (AR) is a respiratory immune system disorder characterized by dysregulation of immune responses. Within the context of AR, gut microbiota and its metabolites have been identified as contributors to immune modulation. These microorganisms intricately connect the respiratory and gut immune systems, forming what is commonly referred to as the gut-lung axis. Xiaoqinglong Decoction (XQLD), a traditional Chinese herbal remedy, is widely utilized in traditional Chinese medicine for the clinical treatment of AR. In this study, it is hypothesized that the restoration of symbiotic microbiota balance within the gut-lung axis plays a pivotal role in supporting the superior long-term efficacy of XQLD in AR therapy. Therefore, the primary objective of this research is to investigate the impact of XQLD on the composition and functionality of the gut microbiota in a murine model of AR. Methods: An ovalbumin-sensitized mouse model to simulate AR was utilized, the improvement of AR symptoms after medication was investigated, and high-throughput sequencing was employed to analyze the gut microbiota composition. Results: XQLD exhibited substantial therapeutic effects in AR mice, notably characterized by a significant reduction in allergic inflammatory responses, considerable alleviation of nasal symptoms, and the restoration of normal nasal function. Additionally, following XQLD treatment, the disrupted gut microbiota in AR mice displayed a tendency toward restoration, showing significant differences compared to the Western medicine (loratadine) group. Discussion: This results revealed that XQLD may enhance AR allergic inflammatory responses through the regulation of intestinal microbiota dysbiosis in mice, thus influencing the dynamics of the gut-lung axis. The proposal of this mechanism provides a foundation for future research in this area.

13.
Microbiome ; 12(1): 94, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38790030

ABSTRACT

BACKGROUND: Microbial secondary metabolites play a crucial role in the intricate interactions within the natural environment. Among these metabolites, ribosomally synthesized and post-translationally modified peptides (RiPPs) are becoming a promising source of therapeutic agents due to their structural diversity and functional versatility. However, their biosynthetic capacity and ecological functions remain largely underexplored. RESULTS: Here, we aim to explore the biosynthetic profile of RiPPs and their potential roles in the interactions between microbes and viruses in the ocean, which encompasses a vast diversity of unique biomes that are rich in interactions and remains chemically underexplored. We first developed TrRiPP to identify RiPPs from ocean metagenomes, a deep learning method that detects RiPP precursors in a hallmark gene-independent manner to overcome the limitations of classic methods in processing highly fragmented metagenomic data. Applying this method to metagenomes from the global ocean microbiome, we uncover a diverse array of previously uncharacterized putative RiPP families with great novelty and diversity. Through correlation analysis based on metatranscriptomic data, we observed a high prevalence of antiphage defense-related and phage-related protein families that were co-expressed with RiPP families. Based on this putative association between RiPPs and phage infection, we constructed an Ocean Virus Database (OVD) and established a RiPP-involving host-phage interaction network through host prediction and co-expression analysis, revealing complex connectivities linking RiPP-encoding prokaryotes, RiPP families, viral protein families, and phages. These findings highlight the potential of RiPP families involved in prokaryote-phage interactions and coevolution, providing insights into their ecological functions in the ocean microbiome. CONCLUSIONS: This study provides a systematic investigation of the biosynthetic potential of RiPPs from the ocean microbiome at a global scale, shedding light on the essential insights into the ecological functions of RiPPs in prokaryote-phage interactions through the integration of deep learning approaches, metatranscriptomic data, and host-phage connectivity. This study serves as a valuable example of exploring the ecological functions of bacterial secondary metabolites, particularly their associations with unexplored microbial interactions. Video Abstract.


Subject(s)
Bacteria , Bacteriophages , Deep Learning , Metagenome , Metagenomics , Peptides , Ribosomes , Peptides/metabolism , Peptides/genetics , Bacteriophages/genetics , Metagenomics/methods , Ribosomes/metabolism , Ribosomes/genetics , Bacteria/genetics , Bacteria/metabolism , Bacteria/virology , Bacteria/classification , Microbiota/genetics , Protein Processing, Post-Translational , Seawater/microbiology , Seawater/virology , Oceans and Seas
14.
Breast Cancer Res Treat ; 206(1): 45-56, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38616207

ABSTRACT

PURPOSE: The significance of postmastectomy radiotherapy (PMRT) in breast cancer patients who initially have clinically node-positive (cN +) status but achieve downstaging to ypN0 following neoadjuvant chemotherapy (NAC) remains uncertain. This study aims to assess the impact of PMRT in this patient subset. METHODS: Patients were enrolled from West China Hospital, Sichuan University from 2008 to 2019. Overall survival (OS), Locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and breast cancer-specific survival (BCSS) were estimated using the Kaplan-Meier method and assessed with the log-rank test. The impact of PMRT was further analyzed by the Cox proportional hazards model. Propensity score matching (PSM) was performed to reduce the selection bias. RESULTS: Of the 333 eligible patients, 189 (56.8%) received PMRT, and 144 (43.2%) did not. At a median follow-up period of 71 months, the five-year LRFS, DMFS, BCSS, and OS rates were 99.1%, 93.4%, 96.4%, and 94.3% for the entire cohort, respectively. Additionally, the 5-year LRFS, DMFS, BCSS, and OS rates were 98.9%, 93.8%, 96.7%, and 94.5% with PMRT and 99.2%, 91.3%, 94.9%, and 92.0% without PMRT, respectively (all p-values not statistically significant). After multivariate analysis, PMRT was not a significant risk factor for any of the endpoints. When further stratified by stage, PMRT did not show any survival benefit for patients with stage II-III diseases. CONCLUSION: In the context of comprehensive treatments, PMRT might be exempted in ypN0 breast cancer patients. Further large-scale, randomized controlled studies are required to investigate the significance of PMRT in this patient subset.


Subject(s)
Breast Neoplasms , Mastectomy , Neoadjuvant Therapy , Neoplasm Staging , Humans , Female , Breast Neoplasms/pathology , Breast Neoplasms/therapy , Breast Neoplasms/mortality , Breast Neoplasms/drug therapy , Breast Neoplasms/radiotherapy , Middle Aged , Neoadjuvant Therapy/methods , Adult , Aged , Retrospective Studies , Radiotherapy, Adjuvant/methods , Chemotherapy, Adjuvant/methods , Lymphatic Metastasis , Neoplasm Recurrence, Local/pathology
15.
Materials (Basel) ; 17(3)2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38591628

ABSTRACT

Unsaturated polyester resin (UPR) with excellent flame retardant is mainly obtained by adding large amounts of flame retardants, usually at the expense of mechanical properties. In this work, a reactive flame retardant containing phosphorus and nitrogen (DOPO-N) was successfully synthesized and incorporated in UPR as a crosslinker. The mechanical and flame-retardant properties of UPR composites were enhanced. UPR/30DOPO-N passed a UL-94 V-1 rating with a limiting oxygen index (LOI) of 30.8%. The tensile strength of UPR/30DOPO-N increased by 24.4%. On this basis, a small amount of modified HNTs (VHNTs) was added to further improve the flame-retardant properties of the composite. With the introduction of 3 wt% VHNTs, the composite passed the UL-94 V-0 rating. The peak of heat release rate (PHRR) and total heat release (THR) of it decreased by 60.7% and 48.3%, respectively. Moreover, the detailed flame-retarding mechanism of DOPO-N and VHNTs was investigated by thermogravimetric infrared spectroscopy (TG-IR), Raman spectra, and X-ray photoelectron spectroscopy (XPS). It was found that DOPO-N played a role in quenching the flame in the gas phase and cooperated with VHNTs to enhance the barrier effect in the condensed phase.

16.
PLoS One ; 19(4): e0281698, 2024.
Article in English | MEDLINE | ID: mdl-38593173

ABSTRACT

Several genes involved in the pathogenesis have been identified, with the human leukocyte antigen (HLA) system playing an essential role. However, the relationship between HLA and a cluster of hematological diseases has received little attention in China. Blood samples (n = 123913) from 43568 patients and 80345 individuals without known pathology were genotyped for HLA class I and II using sequencing-based typing. We discovered that HLA-A*11:01, B*40:01, C*01:02, DQB1*03:01, and DRB1*09:01 were prevalent in China. Furthermore, three high-frequency alleles (DQB1*03:01, DQB1*06:02, and DRB1*15:01) were found to be hazardous in malignant hematologic diseases when compared to controls. In addition, for benign hematologic disorders, 7 high-frequency risk alleles (A*01:01, B*46:01, C*01:02, DQB1*03:03, DQB1*05:02, DRB1*09:01, and DRB1*14:54) and 8 high-frequency susceptible genotypes (A*11:01-A*11:01, B*46:01-B*58:01, B*46:01-B*46:01, C*01:02-C*03:04, DQB1*03:01-DQB1*05:02, DQB1*03:03-DQB1*06:01, DRB1*09:01-DRB1*15:01, and DRB1*14:54-DRB1*15:01) were observed. To summarize, our findings indicate the association between HLA alleles/genotypes and a variety of hematological disorders, which is critical for disease surveillance.


Subject(s)
Hematologic Diseases , Histocompatibility Antigens Class I , Humans , Gene Frequency , Alleles , HLA-DQ beta-Chains/genetics , HLA-DRB1 Chains/genetics , Genotype , Histocompatibility Antigens Class I/genetics , Hematologic Diseases/genetics , Haplotypes , Genetic Predisposition to Disease
17.
Sci Adv ; 10(14): eadk1031, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38569029

ABSTRACT

Pathologic Wnt/ß-catenin signaling drives various cancers, leading to multiple approaches to drug this pathway. Appropriate patient selection can maximize success of these interventions. Wnt ligand addiction is a druggable vulnerability in RNF43-mutant/RSPO-fusion cancers. However, pharmacologically targeting the biogenesis of Wnt ligands, e.g., with PORCN inhibitors, has shown mixed therapeutic responses, possibly due to tumor heterogeneity. Here, we show that the tumor suppressor FBXW7 is frequently mutated in RNF43-mutant/RSPO-fusion tumors, and FBXW7 mutations cause intrinsic resistance to anti-Wnt therapies. Mechanistically, FBXW7 inactivation stabilizes multiple oncoproteins including Cyclin E and MYC and antagonizes the cytostatic effect of Wnt inhibitors. Moreover, although FBXW7 mutations do not mitigate ß-catenin degradation upon Wnt inhibition, FBXW7-mutant RNF43-mutant/RSPO-fusion cancers instead lose dependence on ß-catenin signaling, accompanied by dedifferentiation and loss of lineage specificity. These FBXW7-mutant Wnt/ß-catenin-independent tumors are susceptible to multi-cyclin-dependent kinase inhibition. An in-depth understanding of primary resistance to anti-Wnt/ß-catenin therapies allows for more appropriate patient selection and use of alternative mechanism-based therapies.


Subject(s)
Neoplasms , beta Catenin , Humans , F-Box-WD Repeat-Containing Protein 7/genetics , F-Box-WD Repeat-Containing Protein 7/metabolism , beta Catenin/genetics , beta Catenin/metabolism , Ubiquitin-Protein Ligases/metabolism , Neoplasms/genetics , Mutation , Cell Line, Tumor , Acyltransferases/genetics , Acyltransferases/metabolism , Membrane Proteins/metabolism
18.
J Drug Target ; 32(4): 393-403, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38385350

ABSTRACT

BACKGROUND: Diabetic retinopathy (DR) is a significant complication of diabetes and the primary cause of blindness among working age adults globally. The development of DR is accompanied by oxidative stress, characterised by an overproduction of reactive oxygen species (ROS) and a compromised antioxidant system. Clinical interventions aimed at mitigating oxidative stress through ROS scavenging or elimination are currently available. Nevertheless, these treatments merely provide limited management over the advanced stage of the illness. Ferroptosis is a distinctive form of cell death induced by oxidative stress, which is characterised by irondependent phospholipid peroxidation. PURPOSE: This review aims to synthesise recent experimental evidence to examine the involvement of ferroptosis in the pathological processes of DR, as well as to explicate the regulatory pathways governing oxidative stress and ferroptosis in retina. METHODS: We systematically reviewed literature available up to 2023. RESULTS: This review included 12 studies investigating the involvement of ferroptosis in DR.

19.
J Hazard Mater ; 466: 133205, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38278074

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) have received global concern on adverse effects on pregnancy outcomes. Although human studies have reported fetal exposure to PFAS, the underlying mechanisms driving transplacental transfer of PFAS have not been sufficiently understood. The present study aimed to investigate chemical-specific transplacental transfer of PFAS and potential mechanisms based on a BeWo cell monolayer model. The findings of concentration- and time-dependent transport, asymmetry in bidirectional transport, molecular docking and transporter inhibition experiments indicate that passive diffusion and membrane transporter-involved active transport could collectively determine transplacental transport of PFAS. Membrane transporters could play important roles in chemical-specific transport. The inhibition of OAT transporter resulted in promotion of trans-monolayer transport for most PFAS, while an opposite trend was observed when P-gp, BCRP and MRP transporters were prohibited. By contrast, inhibition of OCT resulted in inhibitory effects on the transport of some PFAS (i.e., PFHxA, PFHpA, PFOA, and PFNA), and promotive effects on the other substances (i.e., PFUdA, PFHpS, PFOS, 6:2 Cl-PFESA and PFOSA). Therefore, simultaneous involvement of diverse membrane transporters in utero could result in complicated influence on transplacental transport. Our work constitutes a solid ground for further exploration of the effects of gestational PFAS exposure on birth outcomes.


Subject(s)
Alkanesulfonic Acids , Environmental Pollutants , Fluorocarbons , Pregnancy , Female , Humans , ATP Binding Cassette Transporter, Subfamily G, Member 2 , Molecular Docking Simulation , Neoplasm Proteins , Membrane Transport Proteins
20.
Magn Reson Med ; 91(3): 987-1001, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37936313

ABSTRACT

PURPOSE: This study aims to develop a high-efficiency and high-resolution 3D imaging approach for simultaneous mapping of multiple key tissue parameters for routine brain imaging, including T1 , T2 , proton density (PD), ADC, and fractional anisotropy (FA). The proposed method is intended for pushing routine clinical brain imaging from weighted imaging to quantitative imaging and can also be particularly useful for diffusion-relaxometry studies, which typically suffer from lengthy acquisition time. METHODS: To address challenges associated with diffusion weighting, such as shot-to-shot phase variation and low SNR, we integrated several innovative data acquisition and reconstruction techniques. Specifically, we used M1-compensated diffusion gradients, cardiac gating, and navigators to mitigate phase variations caused by cardiac motion. We also introduced a data-driven pre-pulse gradient to cancel out eddy currents induced by diffusion gradients. Additionally, to enhance image quality within a limited acquisition time, we proposed a data-sharing joint reconstruction approach coupled with a corresponding sequence design. RESULTS: The phantom and in vivo studies indicated that the T1 and T2 values measured by the proposed method are consistent with a conventional MR fingerprinting sequence and the diffusion results (including diffusivity, ADC, and FA) are consistent with the spin-echo EPI DWI sequence. CONCLUSION: The proposed method can achieve whole-brain T1 , T2 , diffusivity, ADC, and FA maps at 1-mm isotropic resolution within 10 min, providing a powerful tool for investigating the microstructural properties of brain tissue, with potential applications in clinical and research settings.


Subject(s)
Brain , Magnetic Resonance Imaging , Humans , Brain/diagnostic imaging , Magnetic Resonance Imaging/methods , Phantoms, Imaging , Mathematical Concepts
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