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1.
Nature ; 632(8025): 522-527, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39143343

RESUMO

Terahertz (THz) wireless communication holds immense potential to revolutionize future 6G to XG networks with high capacity, low latency and extensive connectivity. Efficient THz beamformers are essential for energy-efficient connections, compensating path loss, optimizing resource usage and enhancing spectral efficiency. However, current beamformers face several challenges, including notable loss, limited bandwidth, constrained spatial coverage and poor integration with on-chip THz circuits. Here we present an on-chip broadband THz topological beamformer using valley vortices for waveguiding, splitting and perfect isolation in waveguide phased arrays, featuring 184 densely packed valley-locked waveguides, 54 power splitters and 136 sharp bends. Leveraging neural-network-assisted inverse design, the beamformer achieves complete 360° azimuthal beamforming with gains of up to 20 dBi, radiating THz signals into free space with customizable user-defined beams. Photoexciting the all-silicon beamformer enables reconfigurable control of THz beams. The low-loss and broadband beamformer enables a 72-Gbps chip-to-chip wireless link over 300 mm and eight simultaneous 40-Gbps wireless links. Using four of these links, we demonstrate point-to-4-point real-time HD video streaming. Our work provides a complementary metal-oxide-semiconductor-compatible THz topological photonic integrated circuit for efficient large-scale beamforming, enabling massive single-input multiple-output and multiple-input and multiple-output systems for terabit-per-second 6G to XG wireless communications.

2.
Proc Natl Acad Sci U S A ; 120(16): e2208450120, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37036985

RESUMO

Average ambient concentrations of nitrogen dioxide (NO2), an important air pollutant, have declined in the United States since the enactment of the Clean Air Act. Despite evidence that NO2 disproportionately affects racial/ethnic minority groups, it remains unclear what drives the exposure disparities and how they have changed over time. Here, we provide evidence by integrating high-resolution (1 km × 1 km) ground-level NO2 estimates, sociodemographic information, and source-specific emission intensity and location for 217,740 block groups across the contiguous United States from 2000 to 2016. We show that racial/ethnic minorities are disproportionately exposed to higher levels of NO2 pollution compared with Whites across the United States and within major metropolitan areas. These inequities persisted over time and have worsened in many cases, despite a significant decrease in the national average NO2 concentration over the 17-y study period. Overall, traffic contributes the largest fraction of NO2 disparity. Contributions of other emission sources to exposure disparities vary by location. Our analyses offer insights into policies aimed at reducing air pollution exposure disparities among races/ethnicities and locations.


Assuntos
Poluição do Ar , Disparidades nos Níveis de Saúde , Dióxido de Nitrogênio , Estados Unidos/etnologia , Dióxido de Nitrogênio/toxicidade , Disparidades Socioeconômicas em Saúde , Análise Espaço-Temporal , Grupos Raciais , Etnicidade , Fatores de Tempo , Humanos
3.
J Transl Med ; 22(1): 57, 2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38221616

RESUMO

BACKGROUND: Cancer-associated fibroblasts (CAFs) are heterogeneous and can influence the progression of prostate cancer in multiple ways; however, their capacity to present and process antigens in PRAD has not been investigated. In this study, antigen presentation and process-related CAFs (APPCAFs) were identified using bioinformatics, and the clinical implications of APPCAF-related signatures in PRAD were investigated. METHODS: SMART technology was used to sequence the transcriptome of primary CAFs isolated from patients undergoing different treatments. Differential expression gene (DEG) screening was conducted. A CD4 + T-cell early activation assay was used to assess the activation degree of CD4 + T cells. The datasets of PRAD were obtained from The Cancer Genome Atlas (TCGA) database and NCBI Gene Expression Omnibus (GEO), and the list of 431 antigen presentation and process-related genes was obtained from the InnateDB database. Subsequently, APP-related CAFs were identified by nonnegative matrix factorization (NMF) based on a single-cell seq (scRNA) matrix. GSVA functional enrichment analyses were performed to depict the biological functions. A risk signature based on APPCAF-related genes (APPCAFRS) was developed by least absolute shrinkage and selection operator (LASSO) regression analysis, and the independence of the risk score as a prognostic factor was evaluated by univariate and multivariate Cox regression analyses. Furthermore, a biochemical recurrence-free survival (BCRFS)-related nomogram was established, and immune-related characteristics were assessed using the ssGSEA function. The immune treatment response in PRAD was further analyzed by the Tumor Immune Dysfunction and Exclusion (TIDE) tool. The expression levels of hub genes in APPCAFRS were verified in cell models. RESULTS: There were 134 upregulated and 147 downregulated genes, totaling 281 differentially expressed genes among the primary CAFs. The functions and pathways of 147 downregulated DEGs were significantly enriched in antigen processing and presentation processes, MHC class II protein complex and transport vesicle, MHC class II protein complex binding, and intestinal immune network for IgA production. Androgen withdrawal diminished the activation effect of CAFs on T cells. NMF clustering of CAFs was performed by APPRGs, and pseudotime analysis yielded the antigen presentation and process-related CAF subtype CTSK + MRC2 + CAF-C1. CTSK + MRC2 + CAF-C1 cells exhibited ligand‒receptor connections with epithelial cells and T cells. Additionally, we found a strong association between CTSK + MRC2 + CAF-C1 cells and inflammatory CAFs. Through differential gene expression analysis of the CTSK + MRC2 + CAF-C1 and NoneAPP-CAF-C2 subgroups, 55 significant DEGs were identified, namely, APPCAFRGs. Based on the expression profiles of APPCAFRGs, we divided the TCGA-PRAD cohort into two clusters using NMF consistent cluster analysis, with the genetic coefficient serving as the evaluation index. Four APPCAFRGs, THBS2, DPT, COL5A1, and MARCKS, were used to develop a prognostic signature capable of predicting BCR occurrence in PRAD patients. Subsequently, a nomogram with stability and accuracy in predicting BCR was constructed based on Gleason grade (p = n.s.), PSA (p < 0.001), T stage (p < 0.05), and risk score (p < 0.01). The analysis of immune infiltration showed a positive correlation between the abundance of resting memory CD4 + T cells, M1 macrophages, resting dendritic cells, and the risk score. In addition, the mRNA expression levels of THBS2, DPT, COL5A1, and MARCKS in the cell models were consistent with the results of the bioinformatics analysis. CONCLUSIONS: APPCAFRS based on four potential APPCAFRGs was developed, and their interaction with the immune microenvironment may play a crucial role in the progression to castration resistance of PRAD. This novel approach provides valuable insights into the pathogenesis of PRAD and offers unexplored targets for future research.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias da Próstata , Masculino , Humanos , Apresentação de Antígeno/genética , Análise de Sequência de RNA , Algoritmos , Prognóstico , Microambiente Tumoral
4.
J Org Chem ; 89(14): 9949-9957, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-38967414

RESUMO

A novel method for synthesizing substituted 4-chloroquinolines has been devised, utilizing a cascade reaction of N-aryl enaminones promoted by bis(trichloromethyl) carbonate (BTC) and triphenylphosphine oxide (TPPO). This approach features accessible starting materials, a broad substrate range, extensive functional group compatibility, gentle reaction conditions, and straightforward operation. Its versatility is evidenced by its facile scalability and suitability for late-stage derivatization. A plausible mechanism involving α-carbonylation, 6π-azaelectrocyclization, and dehydroxychlorination sequence is proposed.

5.
J Pineal Res ; 76(1): e12924, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37941528

RESUMO

Osteoporotic bone defects, a severe complication of osteoporosis, are distinguished by a delayed bone healing process and poor repair quality. While bone marrow-derived mesenchymal stem cells (BMMSCs) are the primary origin of bone-forming osteoblasts, their mitochondrial function is impaired, leading to inadequate bone regeneration in osteoporotic patients. Melatonin is well-known for its antioxidant properties and regulation on bone metabolism. The present study postulated that melatonin has the potential to enhance the repair of osteoporotic bone defects by restoring the mitochondrial function of BMMSCs. In vitro administration of melatonin at varying concentrations (0.01, 1, and 100 µM) demonstrated a significant dose-dependent improvement in the mitochondrial function of BMMSCs obtained from ovariectomized rats (OVX-BMMSCs), as indicated by an elevation in mitochondrial membrane potential, adenosine triphosphate synthesis and expression of mitochondrial respiratory chain factors. Melatonin reduced the level of mitochondrial superoxide by activating the silent information regulator type 1 (SIRT1) and its downstream antioxidant enzymes, particularly superoxide dismutase 2 (SOD2). The protective effects of melatonin were found to be nullified upon silencing of Sirt1 or Sod2, underscoring the crucial role of the SIRT1-SOD2 axis in the melatonin-induced enhancement of mitochondrial energy metabolism in OVX-BMMSCs. To achieve a sustained and localized release of melatonin, silk fibroin scaffolds loaded with melatonin (SF@MT) were fabricated. The study involved the surgical creation of bilateral femur defects in OVX rats, followed by the implantation of SF@MT scaffolds. The results indicated that the application of melatonin partially restored the mitochondrial energy metabolism and osteogenic differentiation of OVX-BMMSCs by reinstating mitochondrial redox homeostasis. These findings suggest that the localized administration of melatonin through bone implants holds potential as a therapeutic approach for addressing osteoporotic bone defects.


Assuntos
Melatonina , Células-Tronco Mesenquimais , Osteoporose , Humanos , Ratos , Animais , Osteogênese , Melatonina/metabolismo , Sirtuína 1/metabolismo , Antioxidantes/uso terapêutico , Medula Óssea/metabolismo , Osteoporose/tratamento farmacológico , Diferenciação Celular , Mitocôndrias/metabolismo , Células Cultivadas
6.
Environ Sci Technol ; 58(33): 14629-14640, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39102579

RESUMO

Graphene quantum dots (GQDs) are used in diverse fields from chemistry-related materials to biomedicines, thus causing their substantial release into the environment. Appropriate visual function is crucial for facilitating the decision-making process within the nervous system. Given the direct interaction of eyes with the environment and even nanoparticles, herein, GQDs, sulfonic acid-doped GQDs (S-GQDs), and amino-functionalized GQDs (A-GQDs) were employed to understand the potential optic neurotoxicity disruption mechanism by GQDs. The negatively charged GQDs and S-GQDs disturbed the response to light stimulation and impaired the structure of the retinal nuclear layer of zebrafish larvae, causing vision disorder and retinal degeneration. Albeit with sublethal concentrations, a considerably reduced expression of the retinal vascular sprouting factor sirt1 through increased DNA methylation damaged the blood-retina barrier. Importantly, the regulatory effect on vision function was influenced by negatively charged GQDs and S-GQDs but not positively charged A-GQDs. Moreover, cluster analysis and computational simulation studies indicated that binding affinities between GQDs and the DNMT1-ligand binding might be the dominant determinant of the vision function response. The previously unknown pathway of blood-retinal barrier interference offers opportunities to investigate the biological consequences of GQD-based nanomaterials, guiding innovation in the industry toward environmental sustainability.


Assuntos
Metilação de DNA , Grafite , Pontos Quânticos , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Grafite/química , Animais , Degeneração Retiniana , Barreira Hematorretiniana/metabolismo , Peixe-Zebra
7.
Respiration ; 103(3): 111-123, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38342097

RESUMO

INTRODUCTION: Benign airway stenosis (BAS) is a severe pathologic condition. Complex stenosis has a high recurrence rate and requires repeated bronchoscopic interventions for achieving optimal control, leading to recurrent BAS (RBAS) due to intraluminal granulation. METHODS: This study explored the potential of autologous regenerative factor (ARF) for treating RBAS using a post-intubation tracheal stenosis canine model. Bronchoscopic follow-ups were conducted, and RNA-seq analysis of airway tissue was performed. A clinical study was also initiated involving 17 patients with recurrent airway stenosis. RESULTS: In the animal model, ARF demonstrated significant effectiveness in preventing further collapse of the injured airway, maintaining airway patency and promoting tissue regeneration. RNA-seq results showed differential gene expression, signifying alterations in cellular components and signaling pathways. The clinical study found that ARF treatment was well-tolerated by patients with no severe adverse events requiring hospitalization. ARF treatment yielded a high response rate, especially for post-intubation tracheal stenosis and idiopathic tracheal stenosis patients. CONCLUSION: The study concludes that ARF presents a promising, effective, and less-invasive method for treating RBAS. ARF has shown potential in prolonging the intermittent period and reducing treatment failure in patients with recurrent tracheal stenosis by facilitating tracheal mucosal wound repair and ameliorating tracheal fibrosis. This novel approach could significantly impact future clinical applications.


Assuntos
Estenose Traqueal , Humanos , Animais , Cães , Estenose Traqueal/etiologia , Estenose Traqueal/cirurgia , Constrição Patológica , Projetos Piloto , Traqueia/patologia , Cicatrização/fisiologia , Estudos Retrospectivos
8.
BMC Musculoskelet Disord ; 25(1): 267, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582848

RESUMO

BACKGROUND: To identify the differences of lumbar lordosis (LL) and sacral slope (SS) angles between two types of postoperative lumbar disc re-herniation, including the recurrence of same level and adjacent segment herniation (ASH). METHODS: We searched the medical records of lumbar disc herniation (LDH) patients with re-herniation with complete imaging data (n = 58) from January 1, 2013 to December 30, 2020 in our hospital. After matching for age and sex, 58 patients with LDH without re-herniation from the same period operated by the same treatment group in our hospital were served as a control group. Re-herniation patients were divided into two groups, same-level recurrent lumbar disc herniation group (rLDHG) and adjacent segment herniation group with or without recurrence (ASHG). The preoperative, postoperative and one month after operation LL and SS were measured on standing radiographs and compared with the control group by using t-test, ANOVA, and rank-sum test. Next, we calculated the odds ratios (ORs) by unconditional logistic regression, progressively adjusted for other confounding factors. RESULTS: Compared with the control group, the postoperative LL and SS were significantly lower in LDH patients with re-herniation. However, there were no differences in LL and SS between ASHG and rLDHG at any stage. After progressive adjustment for confounding factors, no matter what stage is, LL and SS remained unassociated with the two types of re-herniation. CONCLUSIONS: Low postoperative LL and SS angles are associated with degeneration of the remaining disc. Low LL and SS may be independent risk factors for re-herniation but cannot determine type of recurrence (same or adjacent disc level).


Assuntos
Deslocamento do Disco Intervertebral , Lordose , Humanos , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/cirurgia , Lordose/diagnóstico por imagem , Lordose/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Sacro/diagnóstico por imagem , Sacro/cirurgia , Masculino , Feminino
9.
Artigo em Inglês | MEDLINE | ID: mdl-38401065

RESUMO

Objective: Trigeminal neuralgia (TN) is very common in the middle-aged and elderly population and seriously affects the normal life of patients. This study aims to analyze the therapeutic effect of percutaneous balloon compression (PBC) on TN and to explore the clinical significance of NOD-like receptor thermal protein domain associated protein 3 (NLRP3), which not only can provide a reference for the clinical treatment of TN in the future, but also can help the clinic to find a reliable indicator for the assessment of TN condition. Methods: The length of stay, total cost of hospitalization, and adverse reactions during treatment were compared between the two groups. Patients were subjected to assessments or investigations of the Barrow Neurological Institute (BNI) scale, Pittsburgh Sleep Quality Index (PSQI), Self-rating Anxiety Scale (SAS), and Self-rating Depression Scale (SDS) before and after treatment. In addition, NLRP3 in the peripheral blood of patients in the research group was measured, and the correlation of NLRP3 with BNI score and prognosis for recurrence was analyzed. Results: The length of stay and the total cost of hospitalization were respectively (12.10±2.20) d and (26445.96±5553.78) yuan in the research group, significantly reduced than those in the control group (P < .05). And the BNI score, PSQI and SAS/SDS were lower in the research group after treatment (P < .05), but the incidence of facial numbness, herpes orofacialis and masticatory muscle weakness were higher in the research group than in the control group (P < .05). After treatment, NLRP3 decreased in the research group, which was positively correlated with BNI score (P < .05). In addition, NLRP3 showed an excellent effect in predicting recurrence. Conclusion: PBC effectively improved the pain and negative psychological status of patients with TN, and NLRP3 was closely related to the pain of patients with TN. In the future, PBC is used in the clinic to treat TN and improve the prognosis of patients.

10.
Ecotoxicol Environ Saf ; 283: 116859, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39137466

RESUMO

The developmental toxicity and human health risks of triazole fungicides (TFs) have attracted worldwide attention due to the ability to enter the human body in a variety of ways. Nevertheless, the specific mechanism by which TFs exert remains incompletely understood. Given that retinoic acid (RA) signaling pathway are closely related to development, this study aimed to screen and identify developmentally disabled chemicals in commonly used TFs and to reveal the potential effects of TFs on developmental retardation through the RA signaling pathway in mouse embryonic stem cells (mESCs). Specifically, six typical TFs (myclobutanil, tebuconazole, hexaconazole, propiconazole, difenoconazole, and flusilazole) were exposed through the construction of an embryoid bodies (EBs)-based in vitro global differentiation models. Our results clarified that various TFs disturbed lineage commitment during early embryonic development. Crucially, the activation of RA signaling pathway, which alters the expression of key genes and interferes the transport and metabolism of retinol, may be responsible for this effect. Furthermore, molecular docking, molecular dynamics simulations, and experiments using a retinoic acid receptor α inhibitor provide evidence supporting the potential modulatory role of the retinoic acid signaling pathway in developmental injury. The current study offers new insights into the TFs involved in the RA signaling pathway that interfere with the differentiation process of mESCs, which is crucial for understanding the impact of TFs on pregnancy and early development.

11.
Molecules ; 29(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38792176

RESUMO

Utilizing online gradient pressure liquid extraction (OGPLE) coupled with a high-performance liquid chromatography antioxidant analysis system, we examined the antioxidative active components present in both the aerial parts and roots of dandelion. By optimizing the chromatographic conditions, we identified the ferric reducing-antioxidant power system as the most suitable for online antioxidant reactions in dandelion. Compared to offline ultrasonic extraction, the OGPLE method demonstrated superior efficiency in extracting chemical components with varying polarities from the samples. Liquid chromatography-mass spectrometry revealed twelve compounds within the dandelion samples, with nine demonstrating considerable antioxidant efficacy. Of these, the aerial parts and roots of dandelion contained nine and four antioxidant constituents, respectively. Additionally, molecular docking studies were carried out to investigate the interaction between these nine antioxidants and four proteins associated with oxidative stress (glutathione peroxidase, inducible nitric oxide synthase, superoxide dismutase, and xanthine oxidase). The nine antioxidant compounds displayed notable binding affinities below -5.0 kcal/mol with the selected proteins, suggesting potential receptor-ligand interactions. These findings contribute to enhancing our understanding of dandelion and provide a comprehensive methodology for screening the natural antioxidant components from herbs.


Assuntos
Antioxidantes , Simulação de Acoplamento Molecular , Extratos Vegetais , Taraxacum , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Taraxacum/química , Extratos Vegetais/química , Raízes de Plantas/química , Componentes Aéreos da Planta/química
12.
Clin Immunol ; 257: 109843, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37981106

RESUMO

Methicillin-resistant Staphylococcus aureus, poses a significant threat through infections in both community and hospital settings. To address this challenge, we conducted a phase I clinical trial study involving a recombinant Staphylococcus aureus vaccine. Utilizing peripheral blood lymphocytes from 64 subjects, we isolated antigen-specific memory B cells for subsequent single-cell sequencing. Among the 676 identified antigen-binding IgG1+ clones, we selected the top 10 antibody strains for construction within expression vectors. Successful expression and purification of these monoclonal antibodies led to the discovery of a highly expressed human antibody, designated as IgG-6. This antibody specifically targets the pentameric form of the Staphylococcus aureus protein A (SpA5). In vivo assessments revealed that IgG-6 provided prophylactic protection against MRSA252 infection. This study underscores the potential of human antibodies as an innovative strategy against Staphylococcus aureus infections, offering a promising avenue for further research and clinical development.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Staphylococcus aureus , Humanos , Anticorpos Antibacterianos , Anticorpos Monoclonais , Imunoglobulina G , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
13.
Biochem Biophys Res Commun ; 675: 170-176, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37480698

RESUMO

Aerobic glycolysis preferentially exists in many cancer cells. LMO2 is an adaptor protein ubiquitously expressed in many epithelia and their malignancies, and it mediates broad-spectrum protein interactions. In this study, results showed that LMO2 directly interacted with glycolytic enzymes PGK1, PGAM1 and LDHA/LDHB, attenuated the glycolytic metabolism flow characterized by decreased glucose intake, ATP production and lactic acid excretion in lung and breast cancer cells, and was positively associated with of CD8+ T-lymphocyte infiltration in the tumor microenvironment. These findings reveal a novel role of LMO2 on modulating glycolysis in tumor cells and cytotoxic T-lymphocyte infiltration in the tumor microenvironment, which expands our knowledge of LMO2 in the field of solid tumors.


Assuntos
Neoplasias , Linfócitos T Citotóxicos , Humanos , Tórax , Glicólise , Pulmão , Microambiente Tumoral , Proteínas Proto-Oncogênicas , Proteínas Adaptadoras de Transdução de Sinal , Proteínas com Domínio LIM
14.
Opt Express ; 31(12): 19523-19535, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381365

RESUMO

We propose a scheme for the direct generation of an ultrashort pulse train as well as the further compression of pulsed lasers based on the nonlinearity inherent to parity-time (PT) symmetric optical systems. Implementation of optical parametric amplification in a directional coupler of χ(2) waveguides enables ultrafast gain switching through pump-controlled breaking of PT symmetry. We theoretically demonstrate that pumping such a PT symmetric optical system with a periodically amplitude-modulated laser enables periodic gain switching, which can directly convert a continuous-wave signal laser into a train of ultrashort pulses. We further demonstrate that by engineering the PT symmetry threshold, an apodized gain switching that enables the production of ultrashort pulses without side lobes. This work suggests a new approach for exploring the non-linearity inherent to various PT symmetric optical structures to extend optical manipulation capabilities.

15.
Soft Matter ; 19(38): 7370-7378, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37740388

RESUMO

Taking inspiration from the locomotor behaviors of a butterfly, we have developed an underwater soft robot that imitates its movements. This biomimetic robot is constructed using a deformable photo-responsive material that exhibits high biological compatibility and impressive deformation capabilities in response to external stimuli. First, we investigate composite materials consisting of poly-N-isopropylacrylamide (PNIPAM) and multi-walled carbon nanotubes (MWCNTs). Then, using photocuring printing technology, we successfully fabricate a biomimetic butterfly soft robot utilizing these composite materials. The robot is driven by visible light, enabling it to achieve periodic wing movement and fly upward at an average speed of 3.63 mm s-1. In addition, the robot achieves additional functionalities such as flying over obstacles and carrying small objects during the ascending flight. These outcomes have a significant impact on the advancement of flexible biomimetic robots and offer valuable insights for the research of biomimetic robots driven by visible light.

16.
J Org Chem ; 88(20): 14610-14618, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37818975

RESUMO

A one-pot cascade chlorination/heterocyclization strategy has been developed for the synthesis of 2,4-dichloro-substituted quinolines from acylated anilines using triphosgene and triphenylphosphine oxide. Obviating the conventional harsh conditions of chlorination, synthetic useful quinolines with moderate to good yields were obtained through this reaction. The mechanism study exhibited that the formation of a ß-enamine intermediate plays a vital role in the generation of the final product.

17.
Environ Sci Technol ; 57(48): 19990-19998, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37943716

RESUMO

As wildland fires become more frequent and intense, fire smoke has significantly worsened the ambient air quality, posing greater health risks. To better understand the impact of wildfire smoke on air quality, we developed a modeling system to estimate daily PM2.5 concentrations attributed to both fire smoke and nonsmoke sources across the contiguous U.S. We found that wildfire smoke has the most significant impact on air quality in the West Coast, followed by the Southeastern U.S. Between 2007 and 2018, fire smoke contributed over 25% of daily PM2.5 concentrations at ∼40% of all regulatory air monitors in the EPA's air quality system (AQS) for more than one month per year. People residing outside the vicinity of an EPA AQS monitor (defined by a 5 km radius) were subject to 36% more smoke impact days compared with those residing nearby. Lowering the national ambient air quality standard (NAAQS) for annual mean PM2.5 concentrations to between 9 and 10 µg/m3 would result in approximately 35-49% of the AQS monitors falling in nonattainment areas, taking into account the impact of fire smoke. If fire smoke contribution is excluded, this percentage would be reduced by 6 and 9%, demonstrating the significant negative impact of wildland fires on air quality.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Incêndios , Incêndios Florestais , Estados Unidos , Humanos , Poluentes Atmosféricos/análise , Fumaça/análise , Poluição do Ar/análise , Sudeste dos Estados Unidos , Material Particulado
18.
J Phys Chem A ; 127(2): 517-526, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36600536

RESUMO

Molecular diameter is an essential molecule-size descriptor that is widely used to understand, e.g., the gas separation preference of a permeable membrane. In this contribution, we have proposed two new molecular diameters calculated respectively by the circumscribed-cylinder method (Dn') and the group-separated method (Dn), and compared them with the already known kinetic diameter (Dk), averaged diameters (Dpa), and maximum diameters (Dpm and Dmm) in correlating with the penetration barriers of small gas molecules on a total of 14 porous carbon-based monolayer membranes (PCMMs). D1' and D2' give the best barrier-diameter correlations with average Pearson's correlation coefficients of 0.91 and 0.90, which are markedly larger than those (0.77, 0.76, 0.60, 0.48, 0.33, and 0.32) for D1, D2, Dk, Dpa, Dpm, and Dmm. Our results manifest that the choice of vdW radii set does not drastically change the barrier-diameter correlation. Our newly defined D1', D2', D1, and D2, especially D1' and D2', show universal applicability in predicting the relative permeability of small gas molecules on different PCMMs. The circumscribed-cylinder method proposed here is a facile approach that considers the molecule's directionality and can be applicable to larger molecules. The excellent linear correlation between Dn' and gas penetration barrier implies that the computationally less demanding molecular diameter Dn' can be an alternative to the penetration barrier in diagnosing the gas separation preference of the PCMMs.

19.
J Nanobiotechnology ; 21(1): 473, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38066528

RESUMO

BACKGROUND: Gene therapy for lung cancer has emerged as a novel tumor-combating strategy for its superior tumor specificity, low systematical toxicity and huge clinical translation potential. Especially, the applications of microRNA shed led on effective tumor ablation by directly interfering with the crucial gene expression, making it one of the most promising gene therapy agents. However, for lung cancer therapy, the microRNA treatment confronted three bottlenecks, the poor tumor tissue penetration effect, the insufficient lung drug accumulation and unsatisfied gene transfection efficiency. To address these issues, an inhalable RGD-TAT dual peptides-modified cationic liposomes loaded with microRNA miR-34a and gap junction (GJ) regulation agent all-trans retinoic acid (ATRA) was proposed, which was further engineered into dry powder inhalers (DPIs). RESULTS: Equipped with a rough particle surface and appropriate aerodynamic size, the proposed RGD-TAT-CLPs/ARTA@miR-34a DPIs were expected to deposit into the deep lung and reach lung tumor lesions guided by targeting peptide RGD. Assisted by cellular transmembrane peptides TAT, the RGD-TAT-CLPs/ARTA@miR-34a was proven to be effectively internalized by cancer cells, enhancing gene transfection efficiency. Then, the GJ between tumor cells was upregulated by ARTA, facilitating the intercellular transport of miR-34a and boosting the gene expression in the deep tumor. CONCLUSION: Overall, the proposed RGD-TAT-CLPs/ARTA@miR-34a DPIs could enhance tumor tissue penetration, elevate lung drug accumulation and boost gene transfection efficiency, breaking the three bottlenecks to enhancing tumor elimination in vitro and in vivo. We believe that the proposed RGD-TAT-CLPs/ARTA@miR-34a DPIs could serve as a promising pulmonary gene delivery platform for multiple lung local disease treatments.


Assuntos
Neoplasias Pulmonares , MicroRNAs , Humanos , Lipossomos , Neoplasias Pulmonares/terapia , MicroRNAs/genética , MicroRNAs/metabolismo , Pulmão/metabolismo , Oligopeptídeos , Junções Comunicantes/metabolismo , Genes Neoplásicos , Linhagem Celular Tumoral
20.
Lipids Health Dis ; 22(1): 111, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37525169

RESUMO

BACKGROUND: Evidence exists of a strong association between inflammation and a decrease in skeletal muscle function and bone mineral density (BMD); however, the specific mechanisms of these associations remain unclear. Adipokines, as key regulators of the inflammatory response, may be implicated in these processes. The objective of this study was to explore the potential correlation between adipokines, skeletal muscle function and BMD in middle-aged and elderly individuals. METHODS: A comparative cross-sectional study was carried out at the Huadong Hospital Affiliated with Fudan University (Shanghai, China). A total of 460 middle-aged and elderly individuals were recruited, and 125 were enrolled in the analysis. Their biochemical indices, body composition, skeletal muscle function and BMD were measured. Bioinformatic analysis was also employed to identify potential adipokine targets linked to skeletal muscle function and BMD. To validate these targets, plasma and peripheral blood mononuclear cells (PBMCs) were harvested from these individuals and subjected to western blotting (WB) and enzyme-linked immunosorbent assay (ELISA). RESULTS: Individuals in this cross-sectional study were categorized into 2 groups according to their median skeletal muscle mass (SMM) (28.8 kg for males and 20.6 kg for females). Individuals with lower SMM exhibited poorer grip strength (P = 0.017), longer 5-Times-Sit-to-Stand Test (FTSST) duration (P = 0.029), lower total hip BMD (P = 0.043), lower femoral neck BMD (P = 0.011) and higher levels of inflammatory markers in comparison with individuals with higher SMM. Bioinformatics analysis identified LEP, ADIPOQ, RBP4, and DPP4 as potential adipokine targets associated with skeletal muscle function and BMD. In vitro experiments demonstrated that individuals with decreased skeletal muscle function and BMD expressed higher levels of these adipokines. CONCLUSIONS: Skeletal muscle function is positively correlated with BMD and negatively correlated with levels of inflammatory markers among middle-aged and elderly individuals. Those with lower skeletal muscle function and BMD tend to have a higher expression of LEP, ADIPOQ, RBP4 and DPP4.


Assuntos
Adipocinas , Densidade Óssea , Idoso , Masculino , Pessoa de Meia-Idade , Feminino , Humanos , Densidade Óssea/fisiologia , Estudos Transversais , Dipeptidil Peptidase 4 , Leucócitos Mononucleares , China , Músculo Esquelético/fisiologia , Absorciometria de Fóton , Proteínas Plasmáticas de Ligação ao Retinol
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