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1.
J Ovarian Res ; 17(1): 121, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840218

RESUMO

BACKGROUND: Polycystic Ovary Syndrome (PCOS) is a widespread endocrine disorder among women, characterized by symptoms like ovarian cysts, hormonal imbalance, and metabolic issues. This research evaluates the therapeutic potential of Bone Marrow Mesenchymal Stem Cell-derived exosomes (BMSC-Exo) in treating PCOS symptoms within a mouse model. METHODS: BMSC-Exo were isolated from NMRI mice, characterized using Transmission Electron Microscopy (TEM) and Nanoparticle Tracking Analysis (NTA), and administered to a PCOS mouse model induced by dehydroepiandrosterone (DHEA). The efficacy of BMSC-Exo was assessed in three groups of mice: a control group, a PCOS group, and a PCOS group treated with intravenous BMSC-Exo. Morphological changes in ovarian tissue were examined by Hematoxylin and Eosin (H&E) staining, apoptosis was determined using the TUNEL assay, and CD31 expression was analyzed through immunofluorescent staining to assess angiogenic activity. RESULTS: The existence of BMSCs-Exo was confirmed via TEM and NTA, revealing their distinct cup-shaped morphology and a size range of 30 to 150 nanometers. H&E staining revealed that BMSCs-Exo treatment improved ovarian morphology in PCOS models, increasing corpora lutea and revitalizing granulosa cell layers, suggesting a reversal of PCOS-induced damage. TUNEL assays showed that BMSCs-Exo treatment significantly reduced apoptosis in PCOS-affected ovarian cells to levels comparable with the control group, highlighting its role in mitigating PCOS-induced cellular apoptosis. Immunofluorescence for CD31 indicated that BMSCs-Exo treatment normalized endothelial marker expression and angiogenic activity in PCOS models, suggesting its effectiveness in modulating the vascular irregularities of PCOS. Collectively, these findings demonstrate the therapeutic potential of BMSCs-Exo in addressing ovarian dysfunction, cellular apoptosis, and aberrant angiogenesis associated with PCOS. CONCLUSION: The study substantiates the role of BMSC-Exo in mitigating the deleterious effects of PCOS on ovarian tissue, with implications for enhanced follicular development and reduced cellular stress. The modulation of CD31 by BMSC-Exo further highlights their potential in normalizing PCOS-induced vascular anomalies. These findings propel the need for clinical investigations to explore BMSC-Exo as a promising therapeutic avenue for PCOS management.


Assuntos
Apoptose , Desidroepiandrosterona , Modelos Animais de Doenças , Exossomos , Células-Tronco Mesenquimais , Síndrome do Ovário Policístico , Animais , Feminino , Síndrome do Ovário Policístico/terapia , Síndrome do Ovário Policístico/metabolismo , Exossomos/metabolismo , Desidroepiandrosterona/farmacologia , Camundongos , Células-Tronco Mesenquimais/metabolismo , Neovascularização Fisiológica , Ovário/metabolismo , Ovário/patologia , Angiogênese
2.
Gene ; : 148626, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38830516

RESUMO

Cucumber (Cucumis sativus L.) is an important horticultural crop in China. Consumer requirements for aesthetically pleasing appearances of horticultural crops are gradually increasing, and cucumbers having a good visual appearance, as well as flavor, are important for breeding and industry development. The gloss of cucumber fruit epidermis is an important component of its appeal, and the wax layer on the fruit surface plays important roles in plant growth and forms a powerful barrier against external biotic and abiotic stresses. The wax of the cucumber epidermis is mainly composed of alkanes, and the luster of cucumber fruit is mainly determined by the alkane and silicon contents of the epidermis. Several genes, transcription factors, and transporters affect the synthesis of ultra-long-chain fatty acids and change the silicon content, further altering the gloss of the epidermis. However, the specific regulatory mechanisms are not clear. Here, progress in research on the luster of cucumber fruit epidermis from physiological, biochemical, and molecular regulatory perspectives are reviewed. Additionally, future research avenues in the field are discussed.

3.
Inorg Chem ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838348

RESUMO

Surface ligands play crucial roles in modifying the properties of metal nanoclusters and stabilizing atomically precise structures, and also serve as vital linkers for constructing cluster-based coordination polymers. In this study, we present the results of the solvothermal synthesis of eight novel copper alkynyl clusters incorporating pyridine ligands using a one-pot method. The resulting compounds underwent characterization through elemental analysis, Fourier transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction (SCXRD). Our observations revealed that distinct pyridine ligands with varying lengths and coordination sites exert significant influence on the structure and dimensionality of the clusters. The structural diversity of these clusters led to the formation of one-dimensional (1D), two-dimensional (2D), or dimer arrangements linked by seven pyridine bridging ligands. Remarkably, these complexes exhibited unique UV-vis absorption and photoluminescence properties, which were influenced by the specific bridging ligand and structural framework. Furthermore, density functional theory (DFT) calculations demonstrated the capability of the conjugated system in the pyridine ligand to impact the band gap of clusters. This study not only unveils the inherent structural diversity in coordination polymers based on copper alkynyl clusters but also offers valuable insights into harnessing ligand engineering for structural and property modulation.

4.
Sci Total Environ ; 940: 173562, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825197

RESUMO

Epidemic and animal studies have reported that perfluoroalkyl and polyfluoroalkyl substances (PFASs) are strongly associated with liver injury; however, to date, the effects of PFASs on the hepatic microenvironment remain largely unknown. In this study, we established perfluorooctane sulfonic acid (PFOS)-induced liver injury models by providing male and female C57BL/6 mice with water containing PFOS at varying doses for 4 weeks. Hematoxylin and eosin staining revealed that PFOS induced liver injury in both sexes. Elevated levels of serum aminotransferases including those of alanine aminotransferase and aspartate transaminase were detected in the serum of mice treated with PFOS. Female mice exhibited more severe liver injury than male mice. We collected the livers from female mice and performed single-cell RNA sequencing. In total, 36,529 cells were included and grouped into 10 major cell types: B cells, granulocytes, T cells, NK cells, monocytes, dendritic cells, macrophages, endothelial cells, fibroblasts, and hepatocytes. Osteoclast differentiation was upregulated and the T cell receptor signaling pathway was significantly downregulated in PFOS-treated livers. Further analyses revealed that among immune cell clusters in PFOS-treated livers, Tcf7+CD4+T cells were predominantly downregulated, whereas conventional dendritic cells and macrophages were upregulated. Among the fibroblast subpopulations, hepatic stellate cells were significantly enriched in PFOS-treated female mice. CellphoneDB analysis suggested that fibroblasts interact closely with endothelial cells. The major ligand-receptor pairs between fibroblasts and endothelial cells in PFOS-treated livers were Dpp4_Cxcl12, Ackr3_Cxcl12, and Flt1_complex_Vegfa. These genes are associated with directing cell migration and angiogenesis. Our study provides a general framework for understanding the microenvironment in the livers of female mice exposed to PFOS at the single-cell level.

5.
J Cancer ; 15(11): 3350-3361, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817855

RESUMO

This study has used machine learning algorithms to develop a predictive model for differentiating between dermoscopic images of basal cell carcinoma (BCC) and actinic keratosis (AK). We compiled a total of 904 dermoscopic images from two sources - the public dataset (HAM10000) and our proprietary dataset from the First Affiliated Hospital of Dalian Medical University (DAYISET 1) - and subsequently categorised these images into four distinct cohorts. The study developed a deep learning model for quantitative analysis of image features and integrated 15 machine learning algorithms, generating 207 algorithmic combinations through random combinations and cross-validation. The final predictive model, formed by integrating XGBoost with Lasso regression, exhibited effective performance in the differential diagnosis of BCC and AK. The model demonstrated high sensitivity in the training set and maintained stable performance in three validation sets. The area under the curve (AUC) value reached 1.000 in the training set and an average of 0.695 in the validation sets. The study concludes that the constructed discriminative diagnostic model based on machine learning algorithms has excellent predictive capabilities that could enhance clinical decision-making efficiency, reduce unnecessary biopsies, and provide valuable guidance for further treatment.

6.
Front Oncol ; 14: 1386772, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737903

RESUMO

Tumor vasculature is pivotal in regulating tumor perfusion, immune cell infiltration, metastasis, and invasion. The vascular status of the tumor is intricately linked to its immune landscape and response to immunotherapy. Vessel co-option means that tumor tissue adeptly exploits pre-existing blood vessels in the para-carcinoma region to foster its growth rather than inducing angiogenesis. It emerges as a significant mechanism contributing to anti-angiogenic therapy resistance. Different from angiogenic tumors, vessel co-option presents a distinctive vascular-immune niche characterized by varying states and distribution of immune cells, including T-cells, tumor-associated macrophages, neutrophils, and hepatic stellate cells. This unique composition contributes to an immunosuppressive tumor microenvironment that is crucial in modulating the response to cancer immunotherapy. In this review, we systematically reviewed the evidence and molecular mechanisms of vessel co-option in liver cancer, while also exploring its implications for anti-angiogenic drug resistance and the immune microenvironment, to provide new ideas and clues for screening patients with liver cancer who are effective in immunotherapy.

7.
Mater Horiz ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742402

RESUMO

The synthesis of phase-pure carbide nanomaterials is crucial for understanding their structure-performance relationships, and for advancing their application in catalysis. Molybdenum carbides, in particular, have garnered increasing interest due to their Pt-like surface electronic properties and high catalytic activity. Traditional methods for synthesizing molybdenum carbide are often lengthy and energy-intensive, leading to an uncontrolled phase, low purity, and excessive carbon coverage, which hinder their catalytic performance improvement. This work introduces a novel pulsed Joule heating (PJH) technique that overcomes these limitations, enabling the controlled synthesis of high-purity molybdenum carbides (ß-Mo2C, η-MoC1-x, and α-MoC1-x) within seconds by using MoOx/4-Cl-o-phenylenediamine as the hybrid precursor. The PJH method allows precise control over the diffusion of carbon species in the Mo-C system, resulting in a significantly improved phase purity of up to 96.89 wt%. Moreover, the electronic structure of platinum catalysts on molybdenum carbide was modulated through electron metal-support interaction (EMSI) between Pt and MoxC, and contributed to enhanced catalytic performance compared to carbon-supported Pt catalysts during the hydrogen evolution reaction. Overall, this work paves the way for efficient production of high-quality molybdenum carbide nanomaterials, and thus is expected to accelerate their industrial deployments in practical catalytic reactions.

8.
PLoS One ; 19(5): e0302155, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38701096

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is strongly associated with type 2 diabetes mellitus (T2DM). Lifestyle intervention remains a preferred treatment modality for NAFLD. The glucagon-like peptide (GLP-1) receptor agonists and sodium-glucose cotransporter-2 (SGLT-2) inhibitors have been developed as new glucose-lowering drugs, which can improve fatty liver via an insulin-independent glucose-lowering effect. However, studies exploring the efficacy of GLP-1 receptor agonists combined with SGLT-2 inhibitors in patients with NAFLD and T2DM are scanty. Thus, the present randomised controlled trial aims at comparing the efficacy and safety of semaglutide plus empagliflozin with each treatment alone in patients with NAFLD and T2DM. METHODS: This 52-week double-blinded, randomised, parallel-group, active-controlled trial evaluates the effects of semaglutide, empagliflozin and semaglutide + empagliflozin in 105 eligible overweight/obese subjects with NAFLD and T2DM. The primary outcome will be a change from baseline to week 52 in the controlled attenuation parameter, free fatty acid and glucagon. Secondary endpoints include changes in liver stiffness measurement, liver enzymes, blood glucose, lipid levels, renal function, electrolyte balances, minerals and bone metabolism, cytokines, high-sensitivity C-reactive protein, ferritin, anthropometric indicators, nonalcoholic fatty liver fibrosis score, fibrosis 4 score and homeostatic model assessment for insulin resistance. In addition, intention-to-treat, interim analysis and safety analysis will be performed. DISCUSSION: This double-blinded, randomised, clinical trial involves a multi-disciplinary approach and aims to explore the synergistic effects of the combination of semaglutide and empagliflozin. The results can provide important insights into mechanisms of GLP-1 receptor agonists and/or SGLT-2 inhibitors in patients with NAFLD and T2DM. TRIAL REGISTRATION: This study has been registered with Chinese Clinical Trial Registry (ChiCTR2300070674).


Assuntos
Compostos Benzidrílicos , Diabetes Mellitus Tipo 2 , Peptídeos Semelhantes ao Glucagon , Glucosídeos , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/complicações , Glucosídeos/uso terapêutico , Glucosídeos/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Compostos Benzidrílicos/uso terapêutico , Compostos Benzidrílicos/efeitos adversos , Pessoa de Meia-Idade , Masculino , Método Duplo-Cego , Feminino , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/efeitos adversos , Adulto , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Quimioterapia Combinada , Glicemia/metabolismo , Idoso , Resultado do Tratamento
10.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731817

RESUMO

MCPH1 has been identified as the causal gene for primary microcephaly type 1, a neurodevelopmental disorder characterized by reduced brain size and delayed growth. As a multifunction protein, MCPH1 has been reported to repress the expression of TERT and interact with transcriptional regulator E2F1. However, it remains unclear whether MCPH1 regulates brain development through its transcriptional regulation function. This study showed that the knockout of Mcph1 in mice leads to delayed growth as early as the embryo stage E11.5. Transcriptome analysis (RNA-seq) revealed that the deletion of Mcph1 resulted in changes in the expression levels of a limited number of genes. Although the expression of some of E2F1 targets, such as Satb2 and Cdkn1c, was affected, the differentially expressed genes (DEGs) were not significantly enriched as E2F1 target genes. Further investigations showed that primary and immortalized Mcph1 knockout mouse embryonic fibroblasts (MEFs) exhibited cell cycle arrest and cellular senescence phenotype. Interestingly, the upregulation of p19ARF was detected in Mcph1 knockout MEFs, and silencing p19Arf restored the cell cycle and growth arrest to wild-type levels. Our findings suggested it is unlikely that MCPH1 regulates neurodevelopment through E2F1-mediated transcriptional regulation, and p19ARF-dependent cell cycle arrest and cellular senescence may contribute to the developmental abnormalities observed in primary microcephaly.


Assuntos
Pontos de Checagem do Ciclo Celular , Senescência Celular , Inibidor p16 de Quinase Dependente de Ciclina , Camundongos Knockout , Microcefalia , Animais , Camundongos , Senescência Celular/genética , Microcefalia/genética , Microcefalia/metabolismo , Microcefalia/patologia , Pontos de Checagem do Ciclo Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo , Fibroblastos/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo
11.
Nat Hum Behav ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740988

RESUMO

The Han Chinese history is shaped by substantial demographic activities and sociocultural transmissions. However, it remains challenging to assess the contributions of demic and cultural diffusion to Han culture and language, primarily due to the lack of rigorous examination of genetic-linguistic congruence. Here we digitized a large-scale linguistic inventory comprising 1,018 lexical traits across 926 dialect varieties. Using phylogenetic analysis and admixture inference, we revealed a north-south gradient of lexical differences that probably resulted from historical migrations. Furthermore, we quantified extensive horizontal language transfers and pinpointed central China as a dialectal melting pot. Integrating genetic data from 30,408 Han Chinese individuals, we compared the lexical and genetic landscapes across 26 provinces. Our results support a hybrid model where demic diffusion predominantly impacts central China, while cultural diffusion and language assimilation occur in southwestern and coastal regions, respectively. This interdisciplinary study sheds light on the complex social-genetic history of the Han Chinese.

12.
PLoS Negl Trop Dis ; 18(5): e0012131, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38743784

RESUMO

BACKGROUND: Echinococcosis is a natural focal, highly prevalent disease in China. Factors influencing the spread of echinococcosis are not only related to personal exposure but also closely related to the environment itself. The purpose of this study was to explore the influence of environmental factors on the prevalence of human echinococcosis and to provide a reference for prevention and control of echinococcosis in the future. METHODS: Data were collected from 370 endemic counties in China in 2018. By downloading Modis, DEM and other remote-sensing images in 2018. Data on environmental factors, i.e., elevation, land surface temperature (LST) and normalized difference vegetation index (NDVI) were collected. Rank correlation analysis was conducted between each environmental factor and the prevalence of echinococcosis at the county level. Negative binomial regression was used to analyze the impact of environmental factors on the prevalence of human echinococcosis at the county level. RESULTS: According to rank correlation analysis, the prevalence of human echinococcosis in each county was positively correlated with elevation, negatively correlated with LST, and negatively correlated with NDVI in May, June and July. Negative binomial regression showed that the prevalence of human echinococcosis was negatively correlated with annual LST and summer NDVI, and positively correlated with average elevation and dog infection rate. The prevalence of human cystic echinococcosis was inversely correlated with the annual average LST, and positively correlated with both the average elevation and the prevalence rate of domestic animals. The prevalence of human alveolar echinococcosis was positively correlated with both NDVI in autumn and average elevation, and negatively correlated with NDVI in winter. CONCLUSION: The prevalence of echinococcosis in the population is affected by environmental factors. Environmental risk assessment and prediction can be conducted in order to rationally allocate health resources and improve both prevention and control efficiency of echinococcosis.


Assuntos
Equinococose , China/epidemiologia , Humanos , Equinococose/epidemiologia , Fatores de Risco , Animais , Prevalência , Cães , Meio Ambiente , Análise de Regressão
13.
BMC Microbiol ; 24(1): 145, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671363

RESUMO

BACKGROUND: Vibrio parahaemolyticus is the predominant etiological agent of seafood-associated foodborne illnesses on a global scale. It is essential to elucidate the mechanisms by which this pathogen disseminates. Given the existing research predominantly concentrates on localized outbreaks, there is a pressing necessity for a comprehensive investigation to capture strains of V. parahaemolyticus cross borders. RESULTS: This study examined the frequency and genetic attributes of imported V. parahaemolyticus strains among travelers entering Shanghai Port, China, between 2017 and 2019.Through the collection of 21 strains from diverse countries and regions, Southeast Asia was pinpointed as a significant source for the emergence of V. parahaemolyticus. Phylogenetic analysis revealed clear delineation between strains originating from human and environmental sources, emphasizing that underlying genome data of foodborne pathogens is essential for environmental monitoring, food safety and early diagnosis of diseases. Furthermore, our study identified the presence of virulence genes (tdh and tlh) and approximately 120 antibiotic resistance-related genes in the majority of isolates, highlighting their crucial involvement in the pathogenesis of V. parahaemolyticus. CONCLUSIONS: This research enhanced our comprehension of the worldwide transmission of V. parahaemolyticus and its antimicrobial resistance patterns. The findings have important implications for public health interventions and antimicrobial stewardship strategies, underscoring the necessity for epidemiological surveillance of pathogen at international travel hubs.


Assuntos
Doenças Transmitidas por Alimentos , Filogenia , Vibrioses , Vibrio parahaemolyticus , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/isolamento & purificação , Vibrio parahaemolyticus/classificação , Vibrio parahaemolyticus/patogenicidade , Vibrio parahaemolyticus/efeitos dos fármacos , Humanos , China/epidemiologia , Vibrioses/microbiologia , Vibrioses/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/epidemiologia , Genoma Bacteriano/genética , Viagem , Fatores de Virulência/genética , Genômica , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia , Alimentos Marinhos/microbiologia
14.
J Surg Res ; 298: 63-70, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38574463

RESUMO

INTRODUCTION: Isolated partial anomalous pulmonary venous connection (PAPVC) is difficult to diagnose, and surgical indications remain controversial. We reviewed 10 y of isolated PAPVC cases. METHODS: The data of patients with isolated PAPVC admitted to the Anzhen Congenital Heart Disease Department from 2010 to 2019 were reviewed retrospectively. RESULTS: Thirty patients, aged between 4 mo and 32 y, were included in this study. Significant correlations were found between the right ventricle (RV), end-diastolic dimension Z-score (RVED-z) and age (r = 0.398, P = 0.03), and between estimated pulmonary pressure and age (r = 0.423, P = 0.02). However, no significant correlations were found between the RVED-z and the number of anomalous pulmonary veins (r = 0.347, P = 0.061), between estimated pulmonary pressure and the RVED-z (r = 0.218, P = 0.248), and between estimated pulmonary pressure and the number of anomalous veins (r = 0.225, P = 0.232). Transthoracic echocardiography (TTE) confirmed 90% of isolated PAPVC cases. Surgical repair was performed in 29 patients with RV enlargement, persistent low weight, pulmonary hypertension, or respiratory symptoms. Among the surgical patients, nine had elevated pulmonary pressure before surgery, which decreased postoperatively; no mortality or reintervention was observed. The mean duration of echocardiographic follow-up was 1.9 y. CONCLUSIONS: TTE is recommended for routine assessments, and further clarification can be obtained with computed tomography when TTE proves inconclusive for diagnosis. Transesophageal echocardiography and computed tomography are further recommended for adult patients if TTE fails to provide clear results. PAPVC should be considered as an underlying cause when unexplained RV enlargement is observed. Surgery is recommended for patients with RV enlargement, pulmonary hypertension, or respiratory symptoms.


Assuntos
Veias Pulmonares , Síndrome de Cimitarra , Humanos , Estudos Retrospectivos , Masculino , Adulto , Feminino , Adolescente , Criança , Pré-Escolar , Adulto Jovem , Lactente , Síndrome de Cimitarra/cirurgia , Síndrome de Cimitarra/diagnóstico por imagem , Síndrome de Cimitarra/diagnóstico , Veias Pulmonares/anormalidades , Veias Pulmonares/cirurgia , Veias Pulmonares/diagnóstico por imagem , Ecocardiografia
15.
J Am Chem Soc ; 146(22): 15320-15330, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38683738

RESUMO

Palladium hydrides (PdHx) are pivotal in both fundamental research and practical applications across a wide spectrum. PdHx nanocrystals, synthesized by heating in dimethylformamide (DMF), exhibit remarkable stability, granting them widespread applications in the field of electrocatalysis. However, this stability appears inconsistent with their metastable nature. The substantial challenges in characterizing nanoscale structures contribute to the limited understanding of this anomalous phenomenon. Here, through a series of well-conceived experimental designs and advanced characterization techniques, including aberration-corrected scanning transmission electron microscopy (AC-STEM), in situ X-ray diffraction (XRD), and time-of-flight secondary ion mass spectrometry (TOF-SIMS), we have uncovered evidence that indicates the presence of C and N within the lattice of Pd (PdCxNy), rather than H (PdHx). By combining theoretical calculations, we have thoroughly studied the potential configurations and thermodynamic stability of PdCxNy, demonstrating a 2.5:1 ratio of C to N infiltration into the Pd lattice. Furthermore, we successfully modulated the electronic structure of Pd nanocrystals through C and N doping, enhancing their catalytic activity in methanol oxidation reactions. This breakthrough provides a new perspective on the structure and composition of Pd-based nanocrystals infused with light elements, paving the way for the development of advanced catalytic materials in the future.

16.
Sci Rep ; 14(1): 6868, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38514835

RESUMO

The addition of hollow glass microsphere into composites is a method to improve mechanical properties. However, the interfacial debonding of hollow microsphere inevitably causes a decrease in the mechanical properties of the material, which ultimately leads to the failure of the composites. In the numerical simulation of such hollow particle-reinforced composites, the ordinary displacement finite element requires a large number of meshes, which undoubtedly greatly increases the computational cost. In this paper, a new VCFEM is proposed to solve this problem by establishing a two-dimensional Voronoi cell finite element model, deriving the residual energy generalized function of hollow particle-reinforced composites, and calculating the interface debonding. The simulation results are compared with the commercial software MARC, ABAQUS to verify the effectiveness of this VCFEM. The results show that this VCFEM greatly improves the computational efficiency while ensuring the accuracy. Based on this model, this paper also investigates the effect of the generation of interfacial debonding on the overall structure and the effect of different wall thickness of hollow particles on the damage of element debonding.

17.
Int Urol Nephrol ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38436825

RESUMO

PURPOSE: The objective of this study is to investigate the associated risk factors of pulmonary infection in individuals diagnosed with chronic kidney disease (CKD). The primary goal is to develop a predictive model that can anticipate the likelihood of pulmonary infection during hospitalization among CKD patients. METHODS: This retrospective cohort study was conducted at two prominent tertiary teaching hospitals. Three distinct models were formulated employing three different approaches: (1) the statistics-driven model, (2) the clinical knowledge-driven model, and (3) the decision tree model. The simplest and most efficient model was obtained by comparing their predictive power, stability, and practicability. RESULTS: This study involved a total of 971 patients, with 388 individuals comprising the modeling group and 583 individuals comprising the validation group. Three different models, namely Models A, B, and C, were utilized, resulting in the identification of seven, four, and eleven predictors, respectively. Ultimately, a statistical knowledge-driven model was selected, which exhibited a C-statistic of 0.891 (0.855-0.927) and a Brier score of 0.012. Furthermore, the Hosmer-Lemeshow test indicated that the model demonstrated good calibration. Additionally, Model A displayed a satisfactory C-statistic of 0.883 (0.856-0.911) during external validation. The statistical-driven model, known as the A-C2GH2S risk score (which incorporates factors such as albumin, C2 [previous COPD history, blood calcium], random venous blood glucose, H2 [hemoglobin, high-density lipoprotein], and smoking), was utilized to determine the risk score for the incidence rate of lung infection in patients with CKD. The findings revealed a gradual increase in the occurrence of pulmonary infections, ranging from 1.84% for individuals with an A-C2GH2S Risk Score ≤ 6, to 93.96% for those with an A-C2GH2S Risk Score ≥ 18.5. CONCLUSION: A predictive model comprising seven predictors was developed to forecast pulmonary infection in patients with CKD. This model is characterized by its simplicity, practicality, and it also has good specificity and sensitivity after verification.

18.
Front Endocrinol (Lausanne) ; 15: 1347864, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38425757

RESUMO

Diabetic retinopathy (DR) is a highly tissue-specific neurovascular complication of type 1 and type 2 diabetes mellitus and is among the leading causes of blindness worldwide. Pathophysiological changes in DR encompass neurodegeneration, inflammation, and oxidative stress. Current treatments for DR, including anti-vascular endothelial growth factor, steroids, laser photocoagulation, and vitrectomy have limitations and adverse reactions, necessitating the exploration of novel treatment strategies. This review aims to summarize the current pathophysiology, therapeutic approaches, and available drug-delivery methods for treating DR, and discuss their respective development potentials. Recent research indicates the efficacy of novel receptor inhibitors and agonists, such as aldose reductase inhibitors, angiotensin-converting enzyme inhibitors, peroxisome proliferator-activated receptor alpha agonists, and novel drugs in delaying DR. Furthermore, with continuous advancements in nanotechnology, a new form of drug delivery has been developed that can address certain limitations of clinical drug therapy, such as low solubility and poor penetration. This review serves as a theoretical foundation for future research on DR treatment. While highlighting promising therapeutic targets, it underscores the need for continuous exploration to enhance our understanding of DR pathogenesis. The limitations of current treatments and the potential for future advancements emphasize the importance of ongoing research in this field.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/complicações , Diabetes Mellitus Tipo 2/complicações , Inflamação/complicações , Inibidores da Enzima Conversora de Angiotensina , Esteroides/uso terapêutico
19.
Angew Chem Int Ed Engl ; 63(20): e202401206, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38469979

RESUMO

Alloying nanoclusters (NCs) has emerged as a widely explored and versatile strategy for tailoring tunable properties, facilitating in-depth atomic-level investigations of structure-property correlations. In this study, we have successfully synthesized six atomically precise copper NCs alloyed with Group 10 metals (Pd or Pt). Notably, the Pd0 or Pt0 atom situated at the center of the distorted hexagonal antiprism Pd0/Pt0@Cu12 cage, coordinated with twelve Cu+ and two tBuC≡C- ligands. Moreover, ligand exchange strategies demonstrated the potential for Cl- and Br- to replace one or two alkynyl ligands positioned at the top or side of the NCs. The chirality exhibited by these racemic NCs is primarily attributed to the involvement of halogens and a chiral (Pd/Pt)@Cu18 skeleton. Furthermore, all the NCs exhibit near-infrared (NIR) luminescence, characterized by emission peaks at 705-755 nm, lifetimes ranging from 6.630 to 9.662 µs, and absolute photoluminescence quantum yields (PLQYs) of 1.75 %-2.52 % in their crystalline state. The experimental optical properties of these NCs are found to be in excellent agreement with the results of theoretical calculations. These alloy NCs not only offer valuable insights into the synthesis of Pd0/Pt0-Cu alloy NCs, but also bridge the gap in understanding the structure-luminescence relationships of Pd0/Pt0-Cu molecules.

20.
Front Oncol ; 14: 1333094, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384804

RESUMO

Background: The prognostic value of lymph node ratio (LNR) has been proved in several cancers. However, the potential of LNR to be a prognostic factor for thyroid cancer has not been validated so far. This article evaluated the prognostic value of LNR for thyroid cancer through a meta-analysis. Methods: A systematic search was conducted for eligible publications that study the prognostic values of LNR for thyroid cancer in the databases of PubMed, EMBASE, Cochrane, and Web of Science up until October 24, 2023. The quality of the eligible studies was evaluated by The Newcastle-Ottawa Assessment Scale of Cohort Study. The effect measure for meta-analysis was Hazard Ratio (HR). Random effect model was used to calculate the pooled HR and 95% confidence intervals. A sensitivity analysis was applied to assess the stability of the results. Subgroup analysis and a meta-regression were performed to explore the source of heterogeneity. And a funnel plot, Begg's and Egger's tests were used to evaluate publication bias. Results: A total of 15,698 patients with thyroid cancer from 24 eligible studies whose quality were relatively high were included. The pooled HR was 4.74 (95% CI:3.67-6.11; P<0.05) and a moderate heterogeneity was shown (I2 = 40.8%). The results of meta-analysis were stable according to the sensitivity analysis. Similar outcome were shown in subgroup analysis that higher LNR was associated with poorer disease-free survival (DFS). Results from meta-regression indicated that a combination of 5 factors including country, treatment, type of thyroid cancer, year and whether studies control factors in design or analysis were the origin of heterogeneity. Conclusion: Higher LNR was correlated to poorer disease free survival in thyroid cancer. LNR could be a potential prognostic indicator for thyroid cancer. More effort should be made to assess the potential of LNR to be included in the risk stratification systems for thyroid cancer. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=477135, identifier CRD42023477135.

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