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1.
Proc Natl Acad Sci U S A ; 121(7): e2314747121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315853

RESUMO

Macrophages are integral components of the innate immune system, playing a dual role in host defense during infection and pathophysiological states. Macrophages contribute to immune responses and aid in combatting various infections, yet their production of abundant proinflammatory cytokines can lead to uncontrolled inflammation and worsened tissue damage. Therefore, reducing macrophage-derived proinflammatory cytokine release represents a promising approach for treating various acute and chronic inflammatory disorders. However, limited macrophage-specific delivery vehicles have hindered the development of macrophage-targeted therapies. In this study, we screened a pool of 112 lipid nanoparticles (LNPs) to identify an optimal LNP formulation for efficient siRNA delivery. Subsequently, by conjugating the macrophage-specific antibody F4/80 to the LNP surface, we constructed MacLNP, an enhanced LNP formulation designed for targeted macrophage delivery. In both in vitro and in vivo experiments, MacLNP demonstrated a significant enhancement in targeting macrophages. Specifically, delivery of siRNA targeting TAK1, a critical kinase upstream of multiple inflammatory pathways, effectively suppressed the phosphorylation/activation of NF-kB. LNP-mediated inhibition of NF-kB, a key upstream regulator in the classic inflammatory signaling pathway, in the murine macrophage cell line RAW264.7 significantly reduced the release of proinflammatory cytokines after stimulation with the viral RNA mimic Poly(I:C). Finally, intranasal administration of MacLNP-encapsulated TAK1 siRNA markedly ameliorated lung injury induced by influenza infection. In conclusion, our findings validate the potential of targeted macrophage interventions in attenuating inflammatory responses, reinforcing the potential of LNP-mediated macrophage targeting to treat pulmonary inflammatory disorders.


Assuntos
Lipossomos , Nanopartículas , Pneumonia Viral , Camundongos , Humanos , Animais , NF-kappa B/metabolismo , Lipídeos/farmacologia , Macrófagos/metabolismo , RNA Interferente Pequeno/metabolismo , Citocinas/metabolismo , Pneumonia Viral/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(20): e2312855121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38713626

RESUMO

The immune landscape of bladder cancer progression is not fully understood, and effective therapies are lacking in advanced bladder cancer. Here, we visualized that bladder cancer cells recruited neutrophils by secreting interleukin-8 (IL-8); in turn, neutrophils played dual functions in bladder cancer, including hepatocyte growth factor (HGF) release and CCL3highPD-L1high super-immunosuppressive subset formation. Mechanistically, c-Fos was identified as the mediator of HGF up-regulating IL-8 transcription in bladder cancer cells, which was central to the positive feedback of neutrophil recruitment. Clinically, compared with serum IL-8, urine IL-8 was a better biomarker for bladder cancer prognosis and clinical benefit of immune checkpoint blockade (ICB). Additionally, targeting neutrophils or hepatocyte growth factor receptor (MET) signaling combined with ICB inhibited bladder cancer progression and boosted the antitumor effect of CD8+ T cells in mice. These findings reveal the mechanism by which tumor-neutrophil cross talk orchestrates the bladder cancer microenvironment and provide combination strategies, which may have broad impacts on patients suffering from malignancies enriched with neutrophils.


Assuntos
Progressão da Doença , Interleucina-8 , Neutrófilos , Microambiente Tumoral , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/imunologia , Microambiente Tumoral/imunologia , Humanos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Animais , Camundongos , Interleucina-8/metabolismo , Linhagem Celular Tumoral , Fator de Crescimento de Hepatócito/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Antígeno B7-H1/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Feminino , Masculino , Infiltração de Neutrófilos
3.
Nano Lett ; 24(26): 8080-8088, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38888232

RESUMO

Among various mRNA carrier systems, lipid nanoparticles (LNPs) stand out as the most clinically advanced. While current clinical trials of mRNA/LNP therapeutics mainly address liver diseases, the potential of mRNA therapy extends far beyond─yet to be unraveled. To fully unlock the promises of mRNA therapy, there is an urgent need to develop safe and effective LNP systems that can target extrahepatic organs. Here, we report on the development of sulfonium lipid nanoparticles (sLNPs) for systemic mRNA delivery to the lungs. sLNP effectively and specifically delivered mRNA to the lungs following intravenous administration in mice. No evidence of lung and systemic inflammation or toxicity in major organs was induced by sLNP. Our findings demonstrated that the newly developed lung-specific sLNP platform is both safe and efficacious. It holds great promise for advancing the development of new mRNA-based therapies for the treatment of lung-associated diseases and conditions.


Assuntos
Lipídeos , Pulmão , Nanopartículas , RNA Mensageiro , Animais , Pulmão/metabolismo , Nanopartículas/química , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/administração & dosagem , Lipídeos/química , Humanos , Compostos de Sulfônio/química , Técnicas de Transferência de Genes , Lipossomos
4.
Nano Lett ; 24(9): 2719-2726, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38377427

RESUMO

Plasmonic Cu@semiconductor heteronanocrystals (HNCs) have many favorable properties, but the synthesis of solid structures is often hindered by the nanoscale Kirkendall effect. Herein, we present the use of an atomically thin Au3Cu palisade interlayer to reduce lattice mismatch and mediate the Kirkendall effect, enabling the successive topological synthesis of Cu@Au3Cu@Ag, Cu@Au3Cu@Ag2S, and further transformed solid Cu@Au3Cu@CdS core-shell HNCs via cation exchange. The atomically thin and intact Au3Cu palisade interlayer effectively modulates the diffusion kinetics of Cu atoms as demonstrated by experimental and theoretical investigations and simultaneously alleviates the lattice mismatch between Cu and Ag as well as Cu and CdS. The Cu@Au3Cu@CdS HNCs feature exceptional crystallinity and atomically organized heterointerfaces between the plasmonic metal and the semiconductor. This results in the efficient plasmon-induced injection of hot electrons from Cu@Au3Cu into the CdS shell, enabling the Cu@Au3Cu@CdS HNCs to achieve high activity and selectivity for the photocatalytic reduction of CO2 to CO.

5.
Osteoarthritis Cartilage ; 32(8): 950-962, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38782252

RESUMO

OBJECTIVE: Diabetes and other metabolic and inflammatory comorbidities are highly associated with osteoarthritis (OA). However, whether early-life hyperglycemia exposure affects susceptibility to long-term OA is still unknown. The purpose of this study was to explore the fetal origins of OA and provide insights into early-life safeguarding for individual health. METHOD: This study utilized streptozotocin to induce intrauterine hyperglycemia and performed destabilization of the medial meniscus surgery on the knee joints of the offspring mice to induce accelerated OA. Cartilage degeneration-related markers, as well as the expression levels of mitochondrial respiratory chain complexes and mitophagy genes in the adult offspring mice, were investigated. In vitro, mitochondrial function and mitophagy of chondrocyte C28/I2 cells stimulated under high glucose conditions were also evaluated. The methylation levels of the sirt3 gene promoter region in the articular cartilage of intrauterine hyperglycemia-exposed offspring mice were further analyzed. RESULTS: In this study, we found that the intrauterine hyperglycemic environment could lead to an increase in individual susceptibility to OA in late adulthood, mainly due to persistently low levels of Sirt3 expression. Downregulation of Sirt3 causes impaired mitophagy in chondrocytes and abnormal mitochondrial respiratory function due to a failure to clear aged and damaged mitochondria in a timely manner. Overexpressing Sirt3 at the cellular level or using Sirt3 agonists like Honokiol in mouse models can partially rescue mitophagy disorders caused by the hyperglycemic environment and thus alleviate the progression of OA. CONCLUSION: Our study revealed a significantly increased susceptibility to OA in the gestational diabetes mellitus offspring, which is partly attributed to exposure to adverse factors in utero and ultimately to the onset of disease via epigenetic modulation.


Assuntos
Condrócitos , Hiperglicemia , Mitocôndrias , Sirtuína 3 , Animais , Sirtuína 3/metabolismo , Sirtuína 3/genética , Hiperglicemia/metabolismo , Camundongos , Feminino , Gravidez , Condrócitos/metabolismo , Mitocôndrias/metabolismo , Mitofagia , Efeitos Tardios da Exposição Pré-Natal , Cartilagem Articular/metabolismo , Diabetes Mellitus Experimental/metabolismo , Osteoartrite/metabolismo , Osteoartrite/etiologia , Osteoartrite/genética , Metilação de DNA , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/etiologia , Osteoartrite do Joelho/genética
6.
Respir Res ; 25(1): 105, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419020

RESUMO

BACKGROUND: Increasing evidence is appearing that ozone has adverse effects on health. However, the association between long-term ozone exposure and lung function is still inconclusive. OBJECTIVES: To investigate the associations between long-term exposure to ozone and lung function in Chinese young adults. METHODS: We conducted a prospective cohort study among 1594 college students with a mean age of 19.2 years at baseline in Shandong, China from September 2020 to September 2021. Lung function indicators were measured in September 2020 and September 2021, including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), forced expiratory flow at the 25th, 50th, and 75th percentile of the FVC (FEF25, FEF50, and FEF75) and mean flow rate between 25% and 75% of the FVC (FEF25-75) were measured. Daily 10 km×10 km ozone concentrations come from a well-validated data-fusion approach. The time-weighted average concentrations in 12 months before the lung function test were defined as the long-term ozone exposure. The associations between long-term ozone exposure and lung function indicators in Chinese young adults were investigated using a linear mixed effects model, followed by stratified analyses regarding sex, BMI and history of respiratory diseases. RESULTS: Each interquartile range (IQR) (8.9 µg/m3) increase in long-term ozone exposure were associated with a -204.3 (95% confidence interval (CI): -361.6, -47.0) ml/s, -146.3 (95% CI: -264.1, -28.4) ml/s, and - 132.8 (95% CI: -239.2, -26.4) ml/s change in FEF25, FEF50, and FEF25-75, respectively. Stronger adverse associations were found in female participants or those with BMI ≥ 24 kg/m2 and history of respiratory diseases. CONCLUSION: Long-term exposure to ambient ozone is associated with impaired small airway indicators in Chinese young adults. Females, participants with BMI ≥ 24 kg/m2 and a history of respiratory disease have stronger associations.


Assuntos
Poluentes Atmosféricos , Ozônio , Doenças Respiratórias , Humanos , Feminino , Adulto Jovem , Adulto , Pulmão , Estudos Longitudinais , Estudos Prospectivos , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Ozônio/toxicidade , Estudos de Coortes , Volume Expiratório Forçado , Doenças Respiratórias/induzido quimicamente , Doenças Respiratórias/diagnóstico , Doenças Respiratórias/epidemiologia , Poluentes Atmosféricos/análise
7.
Stress ; 27(1): 2293698, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38131654

RESUMO

Studies show that prenatal maternal stress (PNMS) is related to risk for child autism, and to atypical amygdala functional connectivity in the autistic child. Yet, it remains unclear whether amygdala functional connectivity mediates the association between PNMS and autistic traits, particularly in young adult offspring. We recruited women who were pregnant during, or within 3 months of, the 1998 Quebec ice storm crisis, and assessed three aspects of PNMS: objective hardship (events experienced during the ice storm), subjective distress (post-traumatic stress symptoms experienced as a result of the ice storm) and cognitive appraisal. At age 19, 32 young adults (21 females) self-reported their autistic-like traits (i.e., aloof personality, pragmatic language impairment and rigid personality), and underwent structural MRI and resting-state functional MRI scans. Seed-to-voxel analyses were conducted to map the amygdala functional connectivity network. Mediation analyses were implemented with bootstrapping of 20,000 resamplings. We found that greater maternal objective hardship was associated with weaker functional connectivity between the left amygdala and the right postcentral gyrus, which was then associated with more pragmatic language impairment. Greater maternal subjective distress was associated with weaker functional connectivity between the right amygdala and the left precentral gyrus, which was then associated with more aloof personality. Our results demonstrate that the long-lasting effect of PNMS on offspring autistic-like traits may be mediated by decreased amygdala-sensorimotor circuits. The differences between amygdala-sensory and amygdala-motor pathways mediating different aspects of PNMS on different autism phenotypes need to be studied further.


Assuntos
Transtorno Autístico , Transtornos do Desenvolvimento da Linguagem , Efeitos Tardios da Exposição Pré-Natal , Feminino , Humanos , Gravidez , Adulto Jovem , Tonsila do Cerebelo/diagnóstico por imagem , Transtorno Autístico/diagnóstico por imagem , Imageamento por Ressonância Magnética , Fenótipo , Efeitos Tardios da Exposição Pré-Natal/psicologia , Estresse Psicológico/complicações
8.
Inorg Chem ; 63(22): 10358-10365, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38767279

RESUMO

Core-shell nanocrystals (C-S NCs) are an essential class of materials whose structural engineering has attracted wide attention due to their tunable optical and electrical properties, especially noble metal@semiconductor (NMS) C-S NCs with flexible plasmon-exciton coupling. Due to their diverse critical applications, especially aqueous biological applications, herein we propose an aqueous topological strategy enabled by cation exchange reactions (CER) to synthesize various plasmonic Au@semiconductor C-S NCs, in which environmentally friendly triphenylphosphine (TPP) is used as an initiator instead of inflammable tributyl phosphine (TBP). The introduction of the milder, solid TPP facilitated a new aqueous CER strategy for synthesizing Au@semiconductor NCs with tailored chalcogenide compositions and morphologies. For example, the as-synthesized Au@ZnS C-S NRs had better absorption and biocompatibility and exhibited excellent photodynamic therapy efficacy.

9.
Mol Biol Rep ; 51(1): 402, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456942

RESUMO

BACKGROUND: Acetyl-CoA carboxylase (ACC) catalyzes the carboxylation of acetyl-CoA to malonyl-CoA. Malonyl-CoA, which plays a key role in regulating glucose and lipid metabolism, is not only a substrate for fatty acid synthesis but also an inhibitor of the oxidation pathway. ACC exists as two isoenzymes that are encoded by two different genes. ACC1 in grass carp (Ctenopharyngodon idellus) has been cloned and sequenced. However, studies on the cloning, tissue distribution, and function of ACC2 in grass carp were still rare. METHODS AND RESULTS: The full-length cDNA of acc2 was 8537 bp with a 7146 bp open reading frame encoding 2381 amino acids. ACC2 had a calculated molecular weight of 268.209 kDa and an isoelectric point of 5.85. ACC2 of the grass carp shared the closest relationship with that of the common carp (Sinocyclocheilus grahami). The expressions of acc1 and acc2 mRNA were detected in all examined tissues.  The expression level of acc1 was high in the brain and fat but absent in the midgut and hindgut. The expression level of acc2 in the kidney was significantly higher than in other tissues, followed by the heart, brain, muscle, and spleen. ACCs inhibitor significantly reduced the levels of glucose, malonyl-CoA, and triglyceride in hepatocytes. CONCLUSIONS: This study showed that the function of ACC2 was evolutionarily conserved from fish to mammals. ACCs inhibitor inhibited the biological activity of ACCs, and reduced fat accumulation in grass carp.


Assuntos
Carpas , Animais , Carpas/genética , Carpas/metabolismo , Clonagem Molecular , Sequência de Bases , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Expressão Gênica , Glucose , Mamíferos/metabolismo
10.
BMC Public Health ; 24(1): 1373, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778285

RESUMO

BACKGROUND AND OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) and urinary incontinence (UI) are both highly prevalent and age-related diseases. Nevertheless, the link between NAFLD and UI is unclear. Hence, the study was designed to evaluate the association between the NAFLD and UI (including UI types) in a nationally representative sample of United States (US) female adults. METHODS: We conducted this study used data from U.S. female adults in the National Health and Nutrition Examination Survey (NHANES) 2017-March 2020 (pre-pandemic) cycles. The diagnosis of NAFLD is based on Vibration controlled transient elastography (VCTE) and absence of know liver diseases and significant alcohol consumption. The diagnosis and types of UI were assessment using a self-report questionnaire. Multivariable logistic regression models were used to analyze the association between NALFD and UI. Stratified analyses based on age, obesity, race, educational level, married status, PIR, and smoking status were conducted. RESULTS: Of the 2149 participants, the mean (95% CI) age was 53.9 (52.7-55.0), 686 (61.1%) were Non-Hispanic White. UI was significantly more common in participants with NAFLD [490 (64.7%)] than those without NAFLD [552 (44.9%)]. Adjusted for age, race/ethnicity, marital status, educational level, family poverty income ratio (PIR) status, alanine aminotransferase (ALT), aspartate aminotransferase (AST), smoking status, obesity, type 2 diabetes mellitus (T2DM), hypertension and insulin resistance (IR) in a multivariable logistic regression model, NALFD were associated with UI [OR: 1.93, 95%CI 1.23-3.02, P = 0.01] and urge UI [OR: 1.55, 95%CI 1.03-2.33, P = 0.03], while patients with NAFLD did not show an increased odds in stress UI and mixed UI when compared with those without NAFLD subject (P > 0.05). In the subgroup analyses, NAFLD remained significantly associated with UI, particularly among those participants without obesity (OR: 2.69, 95% CI 1.84-4.00) and aged ≥ 60 years (OR: 2.20, 95% CI 1.38-3.51). CONCLUSIONS: Among US female adults, NAFLD has a strong positive correlation with UI. Given that NAFLD is a modifiable disease, these results may help clinicians to target female patients with NAFLD for treatments and interventions that may help prevent the occurrence of UI and reduce the symptoms of UI.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Inquéritos Nutricionais , Incontinência Urinária , Humanos , Feminino , Estados Unidos/epidemiologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Pessoa de Meia-Idade , Incontinência Urinária/epidemiologia , Adulto , Fatores de Risco , Prevalência , Estudos Transversais
11.
Artigo em Inglês | MEDLINE | ID: mdl-38940786

RESUMO

Objective: The research aims to investigate the impact of narrative nursing on the psychological well-being of nursing personnel in the context of the normalization of epidemic. Methods: A cohort of 170 frontline nursing staff at our institution was selected for this clinical study from January 1st to October 31st of 2023. The Symptom Checklist-90 (SCL-90) was employed to evaluate the psychological health of these frontline nursing personnel, compared to the standard norms for nurses in mainland China. Employing a randomized selection method, the cohort was divided into two groups: a control group (85 cases) receiving conventional nursing care and a research group (85 cases) receiving narrative nursing care. The duration of nursing intervention in both groups was set at 12 weeks. Various aspects of psychological well-being, work-related stress, psychological resilience, post-traumatic stress disorder, occupational burnout, job satisfaction, and coping strategies were assessed both before and after the nursing intervention. Results: Among the positive projects of 170 frontline nursing personnel, 32 exhibited positive symptoms, resulting in a positive rate of 18.82%. With the exception of the paranoia dimension score, the scores for other dimensions in the SCL-90 scale within the clinical group were notably higher than those observed in the norm group (P < .05). Among the ten items with the highest frequency of positive symptoms, anxiety, obsessive-compulsive symptoms, and hostility were identified as the most prevalent psychological health issues among frontline nursing personnel. Post-nursing intervention, the research group exhibited lower scores in dimensions other than paranoia in the SCL-90 scale compared to the control group (P < .05). The research group also displayed lower scores in SAS, SDS, SRQ, PCL-C, MBI-HSS and higher scores in CD-RISC and JWS post-intervention (P < .05). In the post-nursing intervention phase, the research group demonstrated lower scores in negative coping and higher scores in positive coping as per the SCSQ scale in comparison to the control group (P < .05). Conclusions: Amidst the ongoing normalization of the epidemic, the psychological well-being of frontline nursing staff was lower than the established norms for nurses in mainland China. Notably, somatization, anxiety, and depression emerged as predominant manifestations. Narrative nursing was identified as an effective intervention to enhance nursing personnel's psychological well-being and coping strategies, ultimately regulating negative emotions, reducing post-traumatic stress disorder and occupational burnout, reducing stress levels, and enhancing job satisfaction and psychological resilience.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38551437

RESUMO

Objective: To investigate the effect of the intervention program based on the Interaction Model of Client Health Behavior (IMCHB) in patients with pressure injury (PI). Methods: The First Affiliated Hospital of Qiqihar Medical University received thirty patients suspected of having pressure injuries from June to December 2022. These patients were selected as the control group. Another thirty patients suspected of having pressure injuries were received by the hospital from January to June 2023 and were selected as the experimental group. The experimental group received a usual care protocol, while the trial group received the IMCHB model intervention for three months. The study compared the knowledge of pressure injuries, quality of life, incidence of pressure injuries, and patient satisfaction of high-risk patients between the two groups. Results: After the intervention, the PI awareness score of caregivers in the experimental group was (31.90 ± 5.24). It is higher than the control group (26.37 ± 6.85). The point of social function, physical function and material function of experimental group were (57.03 ± 5.32), (33.47 ± 3.52) and (58.53 ± 6.93). Respectively, it was higher than the experimental group (48.63 ± 4.80), (27.17 ± 3.04), (46.13 ± 6.72). The incidence of high-risk PI in the experimental group was 3.33%. The point of the control group was 26.67%. The total satisfaction of the experimental group was (8.27 ± 0.78) points, higher than the control group (7.30 ± 0.65). The difference was of statistical significance (P < .05). Conclusion: The intervention program based on IMCHB can significantly improve cognitive ability and thus promote health behavior.

13.
Ecotoxicol Environ Saf ; 281: 116594, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38941662

RESUMO

Chromium (Cr) exposure is associated with various respiratory system diseases, but there are limited studies investigating its impact on lung function in young adults. The Cr exposure-related metabolomic changes are not well elucidated. This study recruited 608 students from a university in Shandong Province, China in 2019. We used cohort design fitted with linear mixed-effects models to assess the association between blood Cr concentration and lung function. In addition, we performed metabolomic and lipidomic analyses of baseline serum samples (N = 582) using liquid chromatography-mass spectrometry. Two-step statistical analysis (analysis of variance and mixed-linear effect model) was used to evaluate the effect of blood Cr exposure on metabolites. We found that blood Cr was associated with decreased lung function in young adults. Each 2-fold increase in blood Cr concentrations was significantly associated with decreased FEV1 and FVC by 35.26 mL (95 % CI: -60.75, -9.78) and 38.56 mL (95 % CI: -66.60, -10.51), respectively. In the metabolomics analysis, blood Cr exposure was significantly associated with 14 key metabolites. The changed metabolites were mainly enriched in six pathways including lipid metabolism, amino acid metabolism, and cofactor vitamin metabolism. Blood Cr may affect lung function through oxidative stress and inflammation related pathways.


Assuntos
Cromo , Pulmão , Metabolômica , Feminino , Humanos , Masculino , Adulto Jovem , China , Cromo/sangue , Estudos de Coortes , População do Leste Asiático , Pulmão/efeitos dos fármacos , Testes de Função Respiratória
14.
Chem Biodivers ; 21(2): e202301655, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38084071

RESUMO

Six novel withanolides, along with nine known related compounds were isolated from the leaves of Datura stramonium L. The structures and absolute configurations of the new withanolides were elucidated by employing various spectral techniques and comparing them with those previously reported in the literature. In addition, four withanlides demonstrated interesting cytotoxic activity on LN229 cells with IC50 <20 µM.


Assuntos
Antineoplásicos , Datura stramonium , Vitanolídeos , Vitanolídeos/farmacologia , Vitanolídeos/química , Estrutura Molecular , Folhas de Planta/química
15.
Sensors (Basel) ; 24(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38931544

RESUMO

Scene text detection is an important research field in computer vision, playing a crucial role in various application scenarios. However, existing scene text detection methods often fail to achieve satisfactory results when faced with text instances of different sizes, shapes, and complex backgrounds. To address the challenge of detecting diverse texts in natural scenes, this paper proposes a multi-scale natural scene text detection method based on attention feature extraction and cascaded feature fusion. This method combines global and local attention through an improved attention feature fusion module (DSAF) to capture text features of different scales, enhancing the network's perception of text regions and improving its feature extraction capabilities. Simultaneously, an improved cascaded feature fusion module (PFFM) is used to fully integrate the extracted feature maps, expanding the receptive field of features and enriching the expressive ability of the feature maps. Finally, to address the cascaded feature maps, a lightweight subspace attention module (SAM) is introduced to partition the concatenated feature maps into several sub-space feature maps, facilitating spatial information interaction among features of different scales. In this paper, comparative experiments are conducted on the ICDAR2015, Total-Text, and MSRA-TD500 datasets, and comparisons are made with some existing scene text detection methods. The results show that the proposed method achieves good performance in terms of accuracy, recall, and F-score, thus verifying its effectiveness and practicality.

16.
Sensors (Basel) ; 24(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39000930

RESUMO

Convolutional neural networks (CNNs) have made significant progress in the field of facial expression recognition (FER). However, due to challenges such as occlusion, lighting variations, and changes in head pose, facial expression recognition in real-world environments remains highly challenging. At the same time, methods solely based on CNN heavily rely on local spatial features, lack global information, and struggle to balance the relationship between computational complexity and recognition accuracy. Consequently, the CNN-based models still fall short in their ability to address FER adequately. To address these issues, we propose a lightweight facial expression recognition method based on a hybrid vision transformer. This method captures multi-scale facial features through an improved attention module, achieving richer feature integration, enhancing the network's perception of key facial expression regions, and improving feature extraction capabilities. Additionally, to further enhance the model's performance, we have designed the patch dropping (PD) module. This module aims to emulate the attention allocation mechanism of the human visual system for local features, guiding the network to focus on the most discriminative features, reducing the influence of irrelevant features, and intuitively lowering computational costs. Extensive experiments demonstrate that our approach significantly outperforms other methods, achieving an accuracy of 86.51% on RAF-DB and nearly 70% on FER2013, with a model size of only 3.64 MB. These results demonstrate that our method provides a new perspective for the field of facial expression recognition.


Assuntos
Expressão Facial , Redes Neurais de Computação , Humanos , Reconhecimento Facial Automatizado/métodos , Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Face , Reconhecimento Automatizado de Padrão/métodos
17.
Nano Lett ; 23(7): 2905-2914, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36961203

RESUMO

Strain engineering is an attractive strategy for improving the intrinsic catalytic performance of heterogeneous catalysts. Manipulating strain on the short-range atomic scale to the local structure of the catalytic sites is still challenging. Herein, we successfully achieved atomic strain modulation on ultrathin layered vanadium oxide nanoribbons by an ingenious intercalation chemistry method. When trace sodium cations were introduced between the V2O5 layers (Na+-V2O5), the V-O bonds were stretched by the atomically strained vanadium sites, redistributing the local charges. The Na+-V2O5 demonstrated excellent photooxidation performance, which was approximately 12 and 14 times higher than that of pristine V2O5 and VO2, respectively. Complementary spectroscopy analysis and theoretical calculations confirmed that the atomically strained Na+-V2O5 had a high surficial charge density, improving the activation of oxygen molecules and contributing to the excellent photocatalytic property. This work provides a new approach for the rational design of strain-equipped catalysts for selective photooxidation reactions.

18.
Small ; 19(44): e2303790, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37381642

RESUMO

Hard carbon is generally accepted as the choice of anode material for sodium-ion batteries. However, integrating high capacity, high initial Coulombic efficiency (ICE), and good durability in hard carbon materials remains challenging. Herein, N-doped hard carbon microspheres (NHCMs) with abundant Na+ adsorption sites and tunable interlayer distance are constructed based on the amine-aldehyde condensation reaction using m-phenylenediamine and formaldehyde as the precursors. The optimized NHCM-1400 with a considerable N content (4.64%) demonstrates a high ICE (87%), high reversible capacity with ideal durability (399 mAh g-1 at 30 mA g-1 and 98.5% retention over 120 cycles), and decent rate capability (297 mAh g-1 at 2000 mA g-1 ). In situ characterizations elucidate the adsorption-intercalation-filling sodium storage mechanism of NHCMs. Theoretical calculation reveals that the N-doping decreases the Na+ adsorption energy on hard carbon.

19.
Small ; 19(8): e2206181, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36504477

RESUMO

Inspired by human eyes, the neuromorphic visual system employs a highly efficient imaging and recognition process, which offers tremendous advantages in image acquisition, data pre-processing, and dynamic storage. However, it is still an enormous challenge to simultaneously simulate the structure, function, and environmental adaptive behavior of the human eye based on one device. Here, a multimodal-synergistic-modulation neuromorphic imaging system based on ultraflexible synaptic transistors is successfully presented and firstly simulates the dry eye imaging behavior at the device level. Moreover, important functions of the human visual system in relation to optoelectronic synaptic plasticity, image erasure and enhancement, real-time preprocessing, and dynamic storage are simulated by versatile devices. This work not only simplifies the complexity of traditional neuromorphic visual systems, but also plays a positive role in the publicity of biomedical eye care.


Assuntos
Síndromes do Olho Seco , Plasticidade Neuronal , Humanos
20.
J Neurosci Res ; 101(12): 1849-1863, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37732456

RESUMO

Studies have shown that prenatal maternal stress (PNMS) affects brain structure and function in childhood. However, less research has examined whether PNMS effects on brain structure and function extend to young adulthood. We recruited women who were pregnant during or within 3 months following the 1998 Quebec ice storm, assessed their PNMS, and prospectively followed-up their children. T1-weighted magnetic resonance imaging (MRI) and resting-state functional MRI were obtained from 19-year-old young adults with (n = 39) and without (n = 65) prenatal exposure to the ice storm. We examined between-group differences in gray matter volume (GMV), surface area (SA), and cortical thickness (CT). We used the brain regions showing between-group GMV differences as seeds to compare between-group functional connectivity. Within the Ice Storm group, we examined (1) associations between PNMS and the atypical GMV, SA, CT, and functional connectivity, and (2) moderation by timing of exposure. Primarily, we found that, compared to Controls, the Ice Storm youth had larger GMV and higher functional connectivity of the anterior cingulate cortex, the precuneus, the left occipital pole, and the right hippocampus; they also had larger CT, but not SA, of the left occipital pole. Within the Ice Storm group, maternal subjective distress during preconception and mid-to-late pregnancy was associated with atypical left occipital pole CT. These results suggest the long-lasting impact of disaster-related PNMS on child brain structure and functional connectivity. Our study also indicates timing-specific effects of the subjective aspect of PNMS on occipital thickness.

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