Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.982
Filtrar
1.
Nat Commun ; 15(1): 8786, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39389980

RESUMEN

In a molecule formed by two atoms, energy difference between bonding and antibonding orbitals depends on distance between the two atoms. However, exploring molecular orbitals of two natural atoms with tunable distance has remained an outstanding experimental challenge. Graphene quantum dots can be viewed as relativistic artificial atoms, thus offering a unique platform to study molecular physics. Here, through scanning tunneling microscope, we create and directly visualize the formation process of relativistic artificial molecules based on two coupled graphene quantum dots with tunable distance. Our study indicates that energy difference between the bonding and antibonding orbitals of the lowest quasibound state increases linearly with inverse distance between the two graphene quantum dots due to the relativistic nature of the artificial molecule. For quasibound states with higher orbital momenta, the coupling between these states leads to half-energy spacing of the confined states because the length of the molecular-like orbit is approximately twice that of the atomic-like orbit. Evolution from ring-like whispering-gallery modes in the artificial atoms to figure-eight orbitals in the artificial molecules is directly imaged. The ability to resolve the coupling and orbitals of the relativistic artificial molecule at the nanoscale level yields insights into the behavior of quantum-relativistic matter.

2.
BMC Public Health ; 24(1): 2761, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39385127

RESUMEN

BACKGROUND: This study aims to explore the relationship between female reproductive factors (age at first birth (AFB), age at last birth (ALB), gravidity, and number of live birth (NLB)) and prevalence of depression among the US women. METHODS: The relationship between AFB, ALB, gravidity, and NLB with the prevalence of depression was explored using publicly available data from the National Health and Nutrition Examination Survey 2005-2018. This cross-sectional study included female participants aged 20 years and older, with reproductive factors and depressive symptoms reported by the participants. Depression was evaluated using the Patient Health Questionnaire-9, with a score of ≥ 10 representing major depression disorder. Weighted multivariable logistic regression and restricted cubic splines (RCS) were utilized to explore the association of AFB, ALB, gravidity and NLB with depression. RESULTS: In this study of 11,488 US women, 1,332 (11.6%) women had depression. Compared to the reference group of women with AFB under 18 years, the fully adjusted ORs and 95% CIs for depression were 0.83 (95% CI: 0.68-0.99), 0.75 (95% CI: 0.60-0.95), and 0.69 (95% CI: 0.51-0.93) for women with AFB of 21-23, 24-26, and 27-29 years, respectively. Furthermore, women with five or more pregnancies had a significantly higher prevalence of depression compared to those with two or fewer pregnancies (OR = 1.20, 95% CI: 1.01-1.42). RCS models demonstrated linear associations of ALB, gravidity and NLB with the prevalence of depression. Additionally, the RCS analysis revealed a roughly L-shaped relationship between AFB and prevalence of depression. CONCLUSIONS: Women with later AFB are associated with a decreased prevalence of depression, while multiple pregnancies are associated with an increased prevalence of depression. These findings suggest that reproductive factors should be considered when screening for and developing preventive strategies for depression.


Asunto(s)
Depresión , Encuestas Nutricionales , Humanos , Femenino , Adulto , Prevalencia , Estudios Transversales , Estados Unidos/epidemiología , Adulto Joven , Depresión/epidemiología , Persona de Mediana Edad , Embarazo , Factores de Riesgo , Número de Embarazos
3.
Nucleic Acids Res ; 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377391

RESUMEN

As the largest family of dicotyledon, the Asteraceae family comprises a variety of economically important crops, ornamental plants and numerous medicinal herbs. Advancements in genomics and transcriptomic have revolutionized research in Asteraceae species, generating extensive omics data that necessitate an efficient platform for data integration and analysis. However, existing databases face challenges in mining genes with specific functions and supporting cross-species studies. To address these gaps, we introduce the Asteraceae Multi-omics Information Resource (AMIR; https://yanglab.hzau.edu.cn/AMIR/), a multi-omics hub for the Asteraceae plant community. AMIR integrates diverse omics data from 74 species, encompassing 132 genomes, 4 408 432 genes annotated across seven different perspectives, 3897 transcriptome sequencing samples spanning 131 organs, tissues and stimuli, 42 765 290 unique variants and 15 662 metabolites genes. Leveraging these data, AMIR establishes the first pan-genome, comparative genomics and transcriptome system for the Asteraceae family. Furthermore, AMIR offers user-friendly tools designed to facilitate extensive customized bioinformatics analyses. Two case studies demonstrate AMIR's capability to provide rapid, reproducible and reliable analysis results. In summary, by integrating multi-omics data of Asteraceae species and developing powerful analytical tools, AMIR significantly advances functional genomics research and contributes to breeding practices of Asteraceae.

5.
J Plast Reconstr Aesthet Surg ; 99: 238-246, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39388766

RESUMEN

BACKGROUND: Secondary unilateral cleft lip nasal deformity is a prevalent condition in the world, and surgical repair remains a formidable challenge. The objective of the study is to investigate functionally and aesthetically outcomes of a new technique using a complex of autologous costal cartilage and fascia grafts to repair the secondary unilateral cleft lip nasal deformity. METHODS: First, the autologous costal cartilage and fascia were harvested from a total of 34 patients with secondary unilateral cleft lip nasal deformity, who were undergoing treatments at the First Affiliated Hospital of Xi'an Jiaotong University from April 2020 to June 2023. Then, the cartilage was sub-divided into 6 pieces and placed on the depressed alar base, nasal columella, lower lateral cartilage, and nasal tip. At the same time, the fascia was trimmed to cover the nasal tip cap graft and augment the dorsum of the nose. Patient outcomes were assessed through subjective evaluation and objective anthropometric measurements. In addition, associated complications were also examined. RESULTS: All were primary healing incisions, and no patients were encountered with any clinical complications. We found that the overall mean score of the Independent Rhinoplasty Outcome Score (IROS) was very good during the subjective assessment. Also, the objective measurements indicated an excellent nasal symmetry. Furthermore, both functionally and aesthetically satisfactory outcomes were obtained in all the patients during long-time follow-up. CONCLUSIONS: Secondary rhinoplasty using the complex of autologous costal cartilage and fascia grafts is a safe and effective approach for unilateral cleft lip nasal deformity repair.

6.
Tissue Cell ; 91: 102575, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39388928

RESUMEN

Exosomes from adipose-derived stem cells (ADSCs) have been demonstrated to benefit angiogenesis, wound healing, and fat grafting. Small noncoding RNAs such as microRNA (miRNA) and circular RNA play critical roles in mediating the function of ADSCs-derived exosomes. However, the underlying mechanisms have not been fully elucidated. In this study, we investigated the function and mechanism of human ADSCs-derived exosomes (hADSCs-Exo) in promoting fat graft angiogenesis and adipogenic differentiation. hADSCs-Exo were isolated and identified, and treatment with hADSCs-Exo enhanced fat graft angiogenesis and adipogenic differentiation in a mouse fat graft implantation model. We found that hADSCs-Exo overexpressed miR-671-3p and promoted human umbilical vein endothelial cell (HUVEC) proliferation, migration, and invasion. Bioinformatics analysis and luciferase reporter assay validated that TMEM127 is a direct target of miR-671-3p. Rescue experiments demonstrated that TMEM127 overexpression partially antagonized the function of hADSCs-Exo in vitro, such as suppressing HUVEC cell proliferation, migration, and invasion. Moreover, TMEM127 overexpression abrogated the function of hADSCs-Exo on fat graft angiogenesis and adipogenic differentiation. Taken together, our findings demonstrate that miR-671-3p-overexpressing exosomes from ADSC promote fat graft angiogenesis and adipogenic differentiation, which highlights the potential of targeting the ADSC-Exosomes-miR-671-3p/TMEM127 axis to improve outcome of fat graft and tissue engineering regenerative medicine.

7.
Nat Commun ; 15(1): 8437, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39349470

RESUMEN

Moiré structures formed by twisting three layers of graphene with two independent twist angles present an ideal platform for studying correlated quantum phenomena, as an infinite set of angle pairs is predicted to exhibit flat bands. Moreover, the two mutually incommensurate moiré patterns among the twisted trilayer graphene (TTG) can form highly tunable moiré quasicrystals. This enables us to extend correlated physics in periodic moiré crystals to quasiperiodic systems. However, direct local characterization of the structure of the moiré quasicrystals and of the resulting flat bands are still lacking, which is crucial to fundamental understanding and control of the correlated moiré physics. Here, we demonstrate the existence of flat bands in a series of TTGs with various twist angle pairs and show that the TTGs with different magic angle pairs are strikingly dissimilar in their atomic and electronic structures. The lattice relaxation and the interference between moiré patterns are highly dependent on the twist angles. Our direct spatial mappings, supported by theoretical calculations, reveal that the localization of the flat bands exhibits distinct symmetries in different regions of the moiré quasicrystals.

8.
Health Commun ; : 1-11, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39263849

RESUMEN

Media literacy plays an increasingly important role in health communication during public health emergencies. The present study aimed to investigate the level of media literacy and its association with disease perceptions and behavioral intentions of receiving vaccination services among young men who have sex with men (YMSM) in China during the 2022 multi-country mpox outbreak. The data were from a large-scale cross-sectional survey conducted among 2,493 YMSM aged 18-29 years in six provincial regions in China in September 2022. A total of 2,079 YMSM who had obtained mpox information from social media platforms were included in this study. Correlation analysis and path analysis were conducted. The mean age of the sample was 24.7. After controlling for background variables, significant positive correlations were found in several pairs between media literacy, mpox-related perceptions (including perceived susceptibility to mpox, perceived severity of mpox, perceived benefits of mpox vaccination, and self-efficacy of receiving mpox vaccination), and the behavioral intention of receiving mpox vaccination. The mpox-related perceptions played a significant mediation role in the association between media literacy and intention of receiving mpox vaccination (indirect effect = 0.165, p < .001, effect size = 82.1%). Media literacy is crucial for developing disease perceptions during public health emergencies and may further influence the adoption of preventive measures. As social media platforms have become the main battle field of health communication during disease outbreaks, improvement of media literacy is urgently warranted.

9.
Biomed Mater ; 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39312953

RESUMEN

Injectable calcium phosphate cement (CPC) offers significant benefits for the minimally invasive repair of irregular bone defects. However, the main limitations of CPC, including its deficiency in osteogenic properties and insufficient large porosity, require further investigation and resolution. In this study, alginate-chitosan-alginate (ACA) microcapsules were used to encapsulate and deliver rat bone mesenchymal stem cells (rBMSCs) into CPC paste, while a porous CPC scaffold was established to support cell growth. Our results demonstrated that the ACA cell microcapsules effectively protect the cells and facilitate their transport into the CPC paste, thereby enhancing cell viability post-implantation. Additionally, the ACA+CPC extracts were found to stimulate osteogenic differentiation of rBMSCs. Furthermore, results from a rat cranial parietal bone defect model showed that ACA microcapsules containing exogenous rBMSCs initially improved the in situ osteogenic potential of CPC within bone defects, providing multiple sites for bone growth. Over time, the osteogenic potential of the exogenous cells diminishes, yet the pores created by the microcapsules persist in supporting ongoing bone formation by recruiting endogenous cells to the osteogenic sites. In conclusion, the utilization of ACA loaded stem cell microcapsules satisfactorily facilitate osteogenesis and degradation of CPC, making it a promising scaffold for bone defect transplantation.

10.
Microbiol Spectr ; : e0083624, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39287458

RESUMEN

Pathogen infections remain a significant public health problem worldwide. Accumulating evidence regarding the crosstalk between bile acid (BA) metabolism and immune response reveals that BA metabolism regulates host immunity and microbial pathogenesis, making it an attractive target for disease prevention and infection control. However, the effect of infection on circulating BA profiles, the biosynthesis-related enzymes, and their receptors remains to be depicted. Here, we investigated the effect of viral (vesicular stomatitis virus, VSV) and bacterial (lipopolysaccharide, LPS) infections on BA metabolism and signaling. Infection models were successfully established by intraperitoneally injecting VSV and LPS, respectively. VSV and LPS injection significantly changed the circulating BA profiles, with highly increased levels of taurine-conjugated BAs and significant decreases in unconjugated BAs. Consistent with the decreased levels of circulating cholic acid (CA) and chenodeoxycholic acid (CDCA), the expression of BA biosynthesis-related rate-limiting enzymes (Cyp7a1, Cyp27a1, Cyp8b1, and Hsd3b7) were significantly reduced. Furthermore, hepatic and pulmonary BA receptors (BARs) expression varied in different infection models. LPS treatment had an extensive impact on tested hepatic and pulmonary BARs, resulting in the upregulation of TGR5, S1PR2, and VDR, while VSV infection only promoted VDR expression. Our study provides insights into the involvement of BA metabolism in the pathophysiology of infection, which may provide potential clues for targeting BA metabolism and BAR signaling to boost innate immunity and control infection. IMPORTANCE: This study focuses on the crosstalk between bile acid (BA) metabolism and immune response in VSV infection and LPS treatment models and depicts the effect of infection on circulating BA profiles, the biosynthesis-related enzymes, and their receptors. These findings provide insights into the effect of infection on BA metabolism and signaling, adding a more comprehensive understanding to the relationship between infection, BA metabolism and immune responses.

11.
Heliyon ; 10(17): e37066, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39296204

RESUMEN

Objective: This study explores the correlation between Forkhead box M1 (FOXM1) and ATP-binding cassette subfamily C member 5 (ABCC5) in relation to paclitaxel resistance in cervical cancer. It aims to identify potential cervical cancer stem cell markers, offering fresh perspectives for developing therapeutic strategies to overcome paclitaxel chemoresistance in cervical cancer. Methods: Paclitaxel-resistant Hela cells (Hela/Taxol) were developed by intermittently exposing Hela cells to progressively increasing concentrations of paclitaxel. We assessed the biological properties of both Hela and Hela/Taxol cells using various assays: cell proliferation, clonogenic, cell cycle, apoptosis, scratch, and transwell. To determine which markers better represent tumor stem cells, we analyzed various known and potential stem cell markers in combination. Flow cytometry was employed to measure the proportion of positive markers in both parental and drug-resistant cell lines. Following statistical analysis to establish relative stability, CD133+ABCC5+ cells were sorted for further examination. Subsequent tests included sphere-forming assays and Western blot analysis to detect the presence of the stem cell-specific protein Sox2, aiding in the identification of viable cervical cancer stem cell markers. Results: The Hela/Taxol cell line exhibited significantly enhanced proliferation, migration, and invasion capabilities compared to the Hela cell line, alongside a marked reduction in apoptosis rates (P < 0.01). Notably, proportions of CD44+, CD24+CD44+, ABCC5+, CD24+CD44+ABCC5+, CD44+ABCC5+, CD24+CD44+FOXM1+, CD44+FOXM1+, CD133+ABCC5+, and CD133+FOXM1+ were significantly higher (P < 0.05). Furthermore, the size and number of spheres formed byCD133+ABCC5+ cells were greater in the sorted Hela/Taxol line (P < 0.01), with increased expression of the stem cell marker Sox2 (P < 0.001). Conclusion: The Hela/Taxol cells demonstrate increased tumoral stemness, suggesting that CD133+ABCC5+ may serve as a novel marker for cervical cancer stem cells.

12.
Medicine (Baltimore) ; 103(22): e38331, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-39259083

RESUMEN

Several observational studies have reported a correlation between the gut microbiota (GM) and the risk of acute pancreatitis (AP). However, the causal relationship between them remains uncertain. We conducted a 2-sample Mendelian randomization (MR) study using pooled data from genome-wide association studies of 211 taxa (131 genera, 35 families, 20 orders, 16 classes, and 9 phyla) and AP patients. We evaluated the causal relationship between the GM and AP using methods such as inverse-variance weighting, MR-Egger, weighted medians, simple mode, and weighted mode. Cochran Q test, MR-Egger regression intercept analysis, and MR-PRESSO were used to examine the heterogeneity, multipotency, and outlier values of the variables, respectively. The reverse causal relationship between AP and the GM was assessed with reverse MR. In total, 5 gut microbial taxa were significantly associated with AP. The inverse-variance weighting results indicated that Acidaminococcaceae (odds ratio [OR]: 0.81, 95% confidence interval [CI]: 0.66-1.00, P = .045) and Ruminococcaceae UCG004 (OR: 0.85, 95% CI: 0.72-0.99, P = .040) were protective factors against the occurrence of AP. Coprococcus 3 (OR: 1.32, 95% CI: 1.03-1.70, P = .030), Eisenbergiella (OR: 1.13, 95% CI: 1.00-1.28, P = .043), and the Eubacterium fissicatena group (OR: 1.18, 95% CI: 1.05-1.33, P = .006) were risk factors for the development of AP. A comprehensive sensitivity analysis proved our results to be reliable. Reverse MR analysis did not indicate any causal relationship between AP and the GM. This study revealed a complex causal relationship between 5 GM taxa and AP, providing new insights into the diagnostic and therapeutic potential of the GM in AP patients.


Asunto(s)
Microbioma Gastrointestinal , Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Pancreatitis , Humanos , Microbioma Gastrointestinal/genética , Pancreatitis/microbiología , Pancreatitis/epidemiología
13.
Sci Total Environ ; 952: 175940, 2024 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-39218083

RESUMEN

Microplastics are heterogeneously distributed in soils. However, it is unknown whether soil microplastic heterogeneity affects plant growth and root foraging responses and whether such effects vary with plant species and microplastic types. We grew each of seven herbaceous species (Platycodon grandiflorus, Trifolium repens, Portulaca oleracea, Medicago sativa, Taraxacum mongolicum, Perilla frutescenst, and Paspalum notatum) in heterogeneous soil (patches without microplastics and patches with 0.2 % microplastics) and homogeneous soil (patches with 0.1 % microplastics). Three microplastic types were tested: polypropylene (PP), polyacrylonitrile (PAN), and polyester (PET). P. frutescens showed no response to soil microplastic heterogeneity. For P. grandiflora, microplastic heterogeneity tended to decrease its biomass (total, shoot and root) when the microplastic was PAN and also shoot biomass when it was PET, but had no effect when it was PP. For T. repens, microplastic heterogeneity promoted biomass when PAN was used, decreased total and root biomass when PET was used, but showed no effect when PP was used. Microplastic heterogeneity increased biomass of P. oleracea and decreased that of M. sativa when PET was used, but had no effect when PP or PAN was used. For T. mongolicum, microplastic heterogeneity reduced biomass when the microplastic was PAN, tended to increase total and root biomass when it was PP, but showed no effect when it was PET. For P. notatum, microplastic heterogeneity increased biomass when the microplastic was PP, decreased it when PET was used, but had no effect when PAN was used. However, biomass of none of the seven species showed root foraging responses at the patch level. Therefore, soil microplastic heterogeneity can influence plant growth, but such effects depend on species and microplastic types and are not associated with root foraging. Our findings highlight the roles of soil microplastic heterogeneity, which may influence species interactions and community structure and productivity.


Asunto(s)
Microplásticos , Contaminantes del Suelo , Suelo , Contaminantes del Suelo/análisis , Microplásticos/toxicidad , Suelo/química , Desarrollo de la Planta/efectos de los fármacos
15.
Anal Chem ; 96(37): 14775-14782, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39238082

RESUMEN

Accurate and rapid imaging of tumor cells is of vital importance for early cancer diagnosis and intervention. Aptamer-based fluorescence sensors have become a potent instrument for bioimaging, while false positives and on-target off-tumors linked to single-biomarker aptasensors compromise the specificity and sensitivity of cancer imaging. In this paper, we describe a sequential response aptasensor for precise cancer cell identification that is based on a DNA "AND" logic gate. Specifically, the sensor consists of three single-stranded DNA, including the P-strand that can sensitively respond to an acid environment, the L-strand containing the ATP aptamer sequence, and the R-strand for target cell anchoring. These DNA strands hybridize with one another to create a Y-shaped structure (named Y-ALGN). The aptamer in the R-strand is utilized to anchor the sensor to the target cell membrane primarily. Responding to the extracellular acidic environment of the tumor (input 1), the I-motif sequence forms a tetramer structure so that the P-strand is released from the Y-shaped structure and exposes the ATP binding sites in the L-strand. Extracellular ATP, as input 2, continuously operates the DNA aptasensor to complete the logic computation. Upon the sequential response of both protons and ATP molecules, the aptasensor is activated with restored fluorescence on a particular cancer cell membrane. Benefiting from the precise computation capacity of the "AND" logic gate, the Y-ALGN aptasensor can distinguish between MCF-7 cells and normal cells with high accuracy. As a simple and dual-stimuli-responsive strategy, this nanodevice would offer a fresh approach for accurately diagnosing tumor cells.


Asunto(s)
Aptámeros de Nucleótidos , Membrana Celular , Aptámeros de Nucleótidos/química , Humanos , Membrana Celular/química , Membrana Celular/metabolismo , Técnicas Biosensibles/métodos , Adenosina Trifosfato/análisis , Adenosina Trifosfato/metabolismo , Imagen Óptica , Colorantes Fluorescentes/química , ADN de Cadena Simple/química , Células MCF-7
16.
Artículo en Inglés | MEDLINE | ID: mdl-39259318

RESUMEN

BACKGROUND: Oncocytic thyroid carcinoma (OTC) is a rare subtype of thyroid cancer known for its distinctive morphology and high likelihood of recurrence, setting it apart from follicular thyroid carcinoma (FTC). Despite this, there is limited research comparing the clinicopathological characteristics and outcomes of OTC and FTC. METHODS: We retrospectively searched through the Surveillance, Epidemiology, and End-Results (SEER) database (2004-2015) for histologically diagnosed OTC and FTC patients. Kaplan-Meier analysis, propensity score matching (PSM), univariate Cox proportional risk regression model, and subgroup analysis were employed to investigate the prognostic effect of clinicopathological features and treatment regimens on survival outcomes of OTC and FTC patients. RESULTS: 2329 OTC patients and 5679 FTC patients were included in the study. OTC patients were prone to older age, white race, lymph node metastasis, distal metastasis, extension and multiple primary tumors compared with FTC patients. After using a 1:1 PSM matching ratio, there were no significant differences in demographic and clinicopathological characteristics between the matched groups. Further Cox regression analysis showed that OTC patients had lower overall survival (OS) and cancer-specific survival (CSS) in contrast with FTC patients. Subgroup survival analysis suggested that the OTC patients were related to lower OS in subgroups including those over 55 years old, male sex, white ethnicity, extrathyroidal extension, single primary tumor, surgery and without chemotherapy compared with the FTC patients in these subgroups. In addition, the OTC patients were connected with lower CSS in subgroups including male sex, white ethnicity, married status, tumor size is less than 20 mm or more than 40 mm, N0 stage, localized stage, single primary tumor, surgery, radiotherapy, and without chemotherapy compared with the FTC patients in these subgroups. Meanwhile, the OTC patients had lower CSS compared to FTC patients regardless of age and extrathyroidal extension. CONCLUSIONS: The results suggested that OTC patients have unique clinical features and poorer prognoses compared to FTC patients. Surgical resection and radioactive iodine therapy are recommended for OTC patients and FTC patients. It is worth noting that the prognosis of OTC relies largely on the selection of treatment strategies. Therefore, our results highlighted the clinical significance of the early distinguishment and the correct choice of treatment in OTC patients.

17.
Org Lett ; 26(36): 7678-7682, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39214529

RESUMEN

An aryne-promoted dehydrosulfurization reaction of thioamides to give nitriles and diaryl sulfides in a one-pot manner is presented. Aromatic, heteroaromatic, and aliphatic natural products and drug-derived nitriles and diaryl sulfides were obtained in good to excellent yields. Especially, selenoamide was also a suitable substrate and produced diaryl selenide and nitrile in high yields. The D-labeled experiments indicated that the protons of thioamides transfer to diaryl sulfides.

18.
Adv Sci (Weinh) ; : e2406095, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39099408

RESUMEN

Catalytic activation of Caryl-O bonds is considered as a powerful strategy for the production of aromatics from lignin. However, due to the high reduction potentials of diaryl ether 4-O-5 linkage models, their single electron reduction remains a daunting challenge. This study presents the blue light-induced bifunctional N-heterocyclic carbene (NHC)-catalyzed one-electron reduction of diaryl ether 4-O-5 linkage models for the synthesis of trivalent phosphines. The H-bond between the newly devised bifunctional NHC and diaryl ethers is responsible for the success of the single electron transfer. Furthermore, this approach demonstrates selective one-electron reduction of unsymmetric diaryl ethers, oligomeric phenylene oxide, and lignin model.

19.
Huan Jing Ke Xue ; 45(8): 4802-4811, 2024 Aug 08.
Artículo en Chino | MEDLINE | ID: mdl-39168697

RESUMEN

Soil heavy metal pollution poses a serious threat to food security, human health, and soil ecosystems. Based on 644 soil samples collected from a typical oasis located at the eastern margin of the Tarim Basin, a series of models, namely, multiple linear regression (LR), neural network (BP), random forest (RF), support vector machine (SVM), and radial basis function (RBF), were built to predict the soil heavy metal content. The optimal prediction result was obtained and utilized to analyze the spatial distribution features of heavy metal contamination and relevant health risks. The outcomes demonstrated that: ① The average Cd content in the study area was 0.14 mg·kg-1, which was 1.17 times the soil background value of Xinjiang, making it the primary factor of soil heavy metal contamination in the area. Additionally, the carcinogenicity risk coefficients of Cd for both adults and children were less than 10-4, indicating that there were no significant long-term health risks for humans in the area. ② The estimation accuracies of the five inversion models were compared, and the validation set of the RF model had an R2 value of 0.763 7, which was the highest among the five models. Additionally, the RMSE, MAE, and MBE of the RF model were the smallest among the five models. Therefore, the predicted values of the RF model were most consistent with the measured values of the soil Cd content. The predicted map of soil Cd distribution derived from the RF model coincided best with the interpolation map. ③ The RF model outperformed the other four models in predicting health risks associated with the soil Cd element for both adults and children, resulting in better prediction results. Comparatively, the predicted values of the LR model in the validation set varied greatly, leading to unreliable results. It was demonstrated that the RF was the best model for predicting soil Cd content and evaluating health risks in the study area, considering its superior generalization capability and anti-overfitting ability.


Asunto(s)
Cadmio , Monitoreo del Ambiente , Aprendizaje Automático , Contaminantes del Suelo , Cadmio/análisis , Contaminantes del Suelo/análisis , Medición de Riesgo , China , Monitoreo del Ambiente/métodos , Humanos , Máquina de Vectores de Soporte , Redes Neurales de la Computación , Suelo/química , Ecosistema , Modelos Lineales
20.
Front Cardiovasc Med ; 11: 1417757, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39161660

RESUMEN

Background and aims: Transcatheter tricuspid valve replacement (TTVR) has recently emerged as a novel therapeutic approach for managing severe tricuspid regurgitation (TR). However, surgical tricuspid valve replacement (STVR) continues to be the predominant treatment modality. There are limited comparative data on both procedures. This study aimed to compare clinical and echocardiographic outcomes between patients who underwent mini-thoracotomy transatrial LuX-Valve TTVR and those who underwent STVR. Methods: This study prospectively collected patients with severe TR who underwent TTVR (n = 29) or isolated STVR (n = 59) at Wuhan Union Hospital from 2019 to 2022. All TTVR patients received the LuX-Valve via a mini-thoracotomy and transatrial approach. The clinical and echocardiographic outcomes were compared at 30-day and one-year follow-ups. Results: At baseline, patients with LuX-Valve TTVR had higher surgical risk scores and a greater proportion of right ventricular dysfunction compared with STVR. In the early postoperative period, the STVR group had a greater decrease in right ventricular function. Hospital length of stay (LOS), intensive care unit LOS, total procedure time, and tracheal intubation time were shorter in the TTVR than in the STVR group. The incidence of postoperative paravalvular leaks was higher among patients who underwent TTVR. Compared to the STVR group, the pacemaker implantation rate was lower in the TTVR group. During follow-up, the peak tricuspid valve velocity and mean gradient in the TTVR group were consistently lower than those in the STVR group. There was similar mortality between TTVR and STVR at 30-day and one-year follow-ups. Conclusions: The mini-thoracotomy transatria LuX-Valve TTVR has a higher incidence of paravalvular leaks and a lower rate of pacemaker implantation than STVR, with similar 30-day and one-year mortality rates. In some respects, mini-thoracotomy transatrial LuX-Valve TTVR may be a feasible and safe treatment option for specific populations, or it could potentially serve as an alternative therapy to supplement conventional STVR. Further follow-up is required to assess differences in long-term clinical outcomes and valve durability.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA