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1.
Front Oncol ; 14: 1394260, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39087027

RESUMO

Penile cancer is a rare malignant tumor of the male urinary system. The treatment benefit of standard first-line chemotherapy is not ideal for patients with locally advanced or metastatic lymph nodes. Immunotherapy has brought new treatment strategies and opportunities for patients with penile cancer. At present, clinical studies on immunotherapy for penile cancer have been reported, and the results show that it is effective but not conclusive. With the development of immunotherapy and the progress of molecular research technology, we can better screen the immunotherapy response population and explore new combination treatment regimens to evaluate the best combination regimen and obtain the optimal treatment options, which is also an important research direction for the immunotherapy of penile cancer in the future.

2.
Fitoterapia ; 178: 106160, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39098734

RESUMO

Patrinia punctiflora is a medical and edible Chinese herb with high nutritional and medicinal value. The continuing study of its chemical constituents led to the isolation of six iridoids, which were previously unreported compounds, patriscabioins PU (1-6). Their structures were characterized and confirmed with NMR (1D & 2D), HRMS, IR and UV. Among them, compound 5 was screened to evaluate its insulin resistance activity on an IR-HepG-2 cell model. Compound 5 had no cytotoxicity compared with the control group and could promote glucose uptake in IR-HepG-2 cells. Through further mechanism studies, the undescribed compound 5 could increase the expression levels of PI-3 K, p-AKT, GLUT4 and p-GSK3ß proteins. Moreover, the expression of PEPCK and G6Pase proteins, which are key gluconeogenic enzymes, was also inhibited. Thus, compound 5 promotes the transfer of GLUT4 to the plasma membrane by activating the PI-3 K/AKT signaling pathway, at the same time, promotes glycogen synthesis and inhibits the onset of gluconeogenesis, which in turn ameliorates insulin resistance.

3.
Tissue Cell ; 90: 102521, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39128192

RESUMO

Larvae are the most important feeding and developmental stage in the life cycle of insects. Correspondingly, the larval midguts, as the primary digestive organs, undergo diverse specialization among insect lineages. Larvae of Scarabaeoidae, commomly known as white grubs, exhibit diversity on feeding habits at the familial or subfamilial level. However, the ultrastructure of larval midguts is not yet satisfactorily understood. In this study, the larval midguts of Trypoxylus dichotomus and Anomala corpulenta were compared using light and transmission electron microscopy for the first time, to uncover the ultrastructural differences between the midguts of saprophagous and phytophagous white grubs. The larval midguts of both species are tubular with three circles of the gastric caeca, and share morphological similarities in midgut epithelial cells, layers of basal lamina, and the digestive and regenerative cells. However, the midguts of the two species differ significantly in the shape of the gastric caeca and exhibit slightly differences in muscle structure. The morphology of larval midgut is related to the feeding habits.

4.
Alzheimers Dement ; 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39129310

RESUMO

INTRODUCTION: The apolipoprotein E (APOE) ε4 allele exerts a significant influence on peripheral inflammation and neuroinflammation, yet the underlying mechanisms remain elusive. METHODS: The present study enrolled 54 patients diagnosed with late-onset Alzheimer's disease (AD; including 28 APOE ε4 carriers and 26 non-carriers). Plasma inflammatory cytokine concentration was assessed, alongside bulk RNA sequencing (RNA-seq) and single-cell RNA sequencing (scRNA-seq) analysis of peripheral blood mononuclear cells (PBMCs). RESULTS: Plasma tumor necrosis factor α, interferon γ, and interleukin (IL)-33 levels increased in the APOE ε4 carriers but IL-7 expression notably decreased. A negative correlation was observed between plasma IL-7 level and the hippocampal atrophy degree. Additionally, the expression of IL-7R and CD28 also decreased in PBMCs of APOE ε4 carriers. ScRNA-seq data results indicated that the changes were mainly related to the CD4+ Tem (effector memory) and CD8+ Tem T cells. DISCUSSION: These findings shed light on the role of the downregulated IL-7/IL-7R pathway associated with the APOE ε4 allele in modulating neuroinflammation and hippocampal atrophy. HIGHLIGHTS: The apolipoprotein E (APOE) ε4 allele decreases plasma interleukin (IL)-7 and aggravates hippocampal atrophy in Alzheimer's disease. Plasma IL-7 level is negatively associated with the degree of hippocampal atrophy. The expression of IL-7R signaling decreased in peripheral blood mononuclear cells of APOE ε4 carriers Dysregulation of the IL-7/IL-7R signal pathways enriches T cells.

5.
Physiol Plant ; 176(4): e14471, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39129657

RESUMO

UV RESISTANCE LOCUS 8 (UVR8) has been identified in Arabidopsis thaliana as the receptor mediating responses to UV-B radiation. However, UVR8-mediated UV-B signaling pathways in rice, which possesses two proteins (UVR8a and UVR8b) with high identities to AtUVR8, remain largely unknown. Here, UVR8a/b were found to be predominantly expressed in rice leaves and leaf sheaths, while the levels of UVR8b transcript and UVR8b protein were both higher than those of UVR8a. Compared to wild-type (WT) plants, uvr8b and uvr8a uvr8b rice mutants exposed to UV-B showed reduced UV-B-induced growth inhibition and upregulation of CHS and HY5 transcripts alongside UV-B acclimation. However, uvr8a mutant was similar to WT plants and exhibited changes comparable with WT. Overexpressing OsUVR8a/b enhanced UV-B-induced growth inhibition and acclimation to UV-B. UV-B was able to enhance the interaction between E3 ubiquitin ligase OsCOP1 and OsUVR8a/b, whereas the interaction of the homologous protein of Arabidopsis REPRESSOR OF UV-B PHOTOMORPHOGENESIS2 (AtRUP2) in rice with OsUVR8a/b was independent of UV-B. Additionally, OsUVR8a/b proteins were also found in the nucleus and cytoplasm even in the absence of UV-B. The abundance of OsUVR8 monomer showed an invisible change in the leaves of rice seedlings transferred from white light to that supplemented with UV-B, even though UV-B was able to weaken the interactions between OsUVR8a and OsUVR8b homo and heterodimers. Therefore, both OsUVR8a and OsUVR8b, which have different localization and response patterns compared with AtUVR8, function in the response of rice to UV-B radiation, whereas OsUVR8b plays a predominant role in this process.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza , Proteínas de Plantas , Raios Ultravioleta , Oryza/genética , Oryza/efeitos da radiação , Oryza/metabolismo , Oryza/fisiologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Folhas de Planta/efeitos da radiação , Folhas de Planta/metabolismo , Folhas de Planta/genética , Mutação
6.
Medicine (Baltimore) ; 103(32): e39277, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39121268

RESUMO

RATIONALE: Traumatic brain injury frequently leads to prolonged coma, posing significant medical management challenges. Complementary therapies, including traditional Chinese herbal medicine, have been investigated as potential interventions in comatose patients. Chinese aromatic herbs, such as Borneolum (Bingpian), Moschus (Shexiang), and Acori tatarinowii rhizoma (Shichangpu), have long been believed to be "resuscitation with aromatics" based on traditional Chinese medicines theory. PATIENT CONCERNS: A 16-year-old male was admitted to the intensive rehabilitation unit for further treatment due to prolonged coma and frequent seizures following traumatic brain injury. DIAGNOSES: Western medicine diagnosed the patient as coma, diffuse axonal injury, and epilepsy. According to traditional Chinese medicine theory, the syndrome differentiation indicates a Yin-closed disease. INTERVENTIONS: According to the patient's condition, we use the Chinese aromatic herbs as a complementary therapy. OUTCOMES: Following a month-long administration, the patient's consciousness and electroencephalogram (EEG) background progressively improved. A 6-month follow-up demonstrated full arousal, though with ambulatory EEG revealing mild to moderate abnormality in the background. LESSONS: The addition of Chinese aromatic herbs appears to have a beneficial effect on the patient's consciousness and EEG background. This could be attributed to the herbs' inherent pharmacological properties, as well as their potential to enhance the permeability of the blood-brain barrier to other drugs. This makes them a promising option for complementary therapy.


Assuntos
Coma , Medicamentos de Ervas Chinesas , Humanos , Masculino , Coma/etiologia , Coma/tratamento farmacológico , Coma/terapia , Medicamentos de Ervas Chinesas/uso terapêutico , Adolescente , Eletroencefalografia , Terapias Complementares/métodos , Lesões Encefálicas Traumáticas/complicações , Medicina Tradicional Chinesa/métodos
7.
Eur J Radiol ; 179: 111664, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39121745

RESUMO

OBJECTIVES: To investigate whether high concentration iodinated contrast media (CM), compared with low concentration CM, could reduce pain and discomfort levels in patients who had level II and III venous conditions. METHODS: This prospective, single-center study enrolled patients who had level II and III venous conditions and underwent abdominal contrast-enhanced CT scan between July 2021 and February 2022. The venous condition to establish peripheral venous access for CM injection was graded using the Intravenous Access Scoring system, of which level II and III indicated poor venous condition and difficult venous access. Patients received iomeprol 400 in high concentration group and ioversol 320 in low group at an identical iodine delivery rate of 1.12 gI/s. The primary outcomes were pain and comfort levels. The secondary outcomes included adverse events and image quality. Patients rated pain intensity via Numerical Rating Scale and comfort level via Visual Analogue Scale with higher scores indicating higher levels of pain and discomfort. Quantitative and qualitative image assessment were compared between two groups. Continuous variables were compared using Student's t test or Mann-Whitney U test. Categorical variables were compared using χ2 test, χ2 test for trend or Fisher's exact test. RESULTS: A total of 206 patients (mean age, 60.13 ± 12.14 years; 81 males) were included with 99 in the high concentration group and 107 in the low concentration group. The high group had significantly lower pain scores (median 1 [IQR: 0-2] vs 2 (IQR 2-4), p < 0.001) and comfort scores (1 [IQR: 0-3] vs 3 [IQR: 2-5], p < 0.001) than the low group. Incidence of CM extravasation did not significantly differ (1.0 % vs 4.5 %, p = 0.214). No hypersensitivity reaction was observed. Qualitative assessment showed higher clarity scores of intrahepatic hepatic artery and portal vein in the high group. Quantitative assessment results were comparable between two groups. CONCLUSION: High concentration iodinated CM could lower pain intensity and improve comfort levels without comprising image quality of CT scan. High concentration CM is a preferable choice in patients with poor venous conditions during contrast-enhanced CT scan.

8.
Angew Chem Int Ed Engl ; : e202412337, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106111

RESUMO

A cascade Nazarov cyclization/dicycloexpansions reaction was developed for the precise synthesis of the angularly fused M/5/N (M = 5, 6; N = 4-9, 13) tricyclic skeletons. The prioritized expansion of the first ring played a critical role in the transformations, due to the release of ring strain, and the nature of the substituents present on the substrate is another influencing factor. This pioneering cascade reaction features broad substrates scope (33 examples), short reaction time, exceptional yields (up to 95%), and remarkable regioselectivities (> 20:1). Exploiting the synthetic application of this cascade reaction, we successfully executed a succinct total synthesis of nominal madreporanone for the first time.

9.
Anal Chem ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109704

RESUMO

Mitochondrial DNA (mtDNA) is pivotal for mitochondrial morphology and function. Upon mtDNA damage, mitochondria undergo quality control mechanisms, including fusion, fission, and mitophagy. Real-time monitoring of mtDNA enables a deeper understanding of its effect on mitochondrial function and morphology. Controllable induction and real-time tracking of mtDNA dynamics and behavior are of paramount significance for studying mitochondrial function and morphology, facilitating a deeper understanding of mitochondria-related diseases. In this work, a fluorescent platinum complex was designed and developed that not only induces mitochondrial DNA (mtDNA) aggregation but also triggers mitochondrial autophagy (mitophagy) through the MDV pathway for damaged mtDNA clearance in living cells. Additionally, this complex allows for the real-time monitoring of these processes. This complex may serve as a valuable tool for studying mitochondrial microautophagy and holds promise for broader applications in cellular imaging and disease research.

10.
Eur J Med Res ; 29(1): 403, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095909

RESUMO

PURPOSE: This current study attempted to investigate whether one-stitch method (OM) of temporary ileostomy influenced the stoma-related complications after laparoscopic low anterior resection (LLAR). METHODS: We searched for eligible studies in four databases including PubMed, Embase, Cochrane Library, and CNKI from inception to July 20, 2023. Both surgical outcomes and stoma-related complications were compared between the OM group and the traditional method (TM) group. The Newcastle-Ottawa Scale (NOS) was adopted for quality assessment. RevMan 5.4 was conducted for data analyzing. RESULTS: Totally 590 patients from six studies were enrolled in this study (272 patients in the OM group and 318 patients in the TM group). No significant difference was found in baseline information (P > 0.05). Patients in the OM group had shorter operative time in both the primary LLAR surgery (MD = - 17.73, 95%CI = - 25.65 to - 9.80, P < 0.01) and the stoma reversal surgery (MD = - 18.70, 95%CI = - 22.48 to -14.92, P < 0.01) than patients in the TM group. There was no significant difference in intraoperative blood loss of the primary LLAR surgery (MD = - 2.92, 95%CI = - 7.15 to 1.32, P = 0.18). Moreover, patients in the OM group had fewer stoma-related complications than patients in the TM group (OR = 0.55, 95%CI = 0.38 to 0.79, P < 0.01). CONCLUSION: The OM group had shorter operation time in both the primary LLAR surgery and the stoma reversal surgery than the TM group. Moreover, the OM group had less stoma-related complications.


Assuntos
Ileostomia , Laparoscopia , Complicações Pós-Operatórias , Neoplasias Retais , Humanos , Ileostomia/efeitos adversos , Ileostomia/métodos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Neoplasias Retais/cirurgia , Complicações Pós-Operatórias/etiologia , Estomas Cirúrgicos/efeitos adversos , Duração da Cirurgia , Feminino , Masculino
11.
Front Neurosci ; 18: 1433583, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39099632

RESUMO

Background: Parkinson's disease (PD) is a prevalent neurodegenerative disorder affecting millions globally. It encompasses both motor and non-motor symptoms, with a notable impact on patients' quality of life. Electroencephalogram (EEG) is a non-invasive tool that is increasingly utilized to investigate neural mechanisms in PD, identify early diagnostic markers, and assess therapeutic responses. Methods: The data were sourced from the Science Citation Index Expanded within the Web of Science Core Collection database, focusing on publications related to EEG research in PD from 2004 to 2023. A comprehensive bibliometric analysis was conducted using CiteSpace and VOSviewer software. The analysis began with an evaluation of the selected publications, identifying leading countries, institutions, authors, and journals, as well as co-cited references, to summarize the current state of EEG research in PD. Keywords are employed to identify research topics that are currently of interest in this field through the analysis of high-frequency keyword co-occurrence and cluster analysis. Finally, burst keywords were identified to uncover emerging trends and research frontiers in the field, highlighting shifts in interest and identifying future research directions. Results: A total of 1,559 publications on EEG research in PD were identified. The United States, Germany, and England have made notable contributions to the field. The University of London is the leading institution in terms of publication output, with the University of California closely following. The most prolific authors are Brown P, Fuhr P, and Stam C In terms of total citations and per-article citations, Stam C has the highest number of citations, while Brown P has the highest H-index. In terms of the total number of publications, Clinical Neurophysiology is the leading journal, while Brain is the most highly cited. The most frequently cited articles pertain to software toolboxes for EEG analysis, neural oscillations, and PD pathophysiology. Through analyzing the keywords, four research hotspots were identified: research on the neural oscillations and connectivity, research on the innovations in EEG Analysis, impact of therapies on EEG, and research on cognitive and emotional assessments. Conclusion: This bibliometric analysis demonstrates a growing global interest in EEG research in PD. The investigation of neural oscillations and connectivity remains a primary focus of research. The application of machine learning, deep learning, and task analysis techniques offers promising avenues for future research in EEG and PD, suggesting the potential for advancements in this field. This study offers valuable insights into the major research trends, influential contributors, and evolving themes in this field, providing a roadmap for future exploration.

12.
Transl Neurodegener ; 13(1): 39, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095921

RESUMO

BACKGROUND: Deoxyribonuclease 2 (DNase II) plays a key role in clearing cytoplasmic double-stranded DNA (dsDNA). Deficiency of DNase II leads to DNA accumulation in the cytoplasm. Persistent dsDNA in neurons is an early pathological hallmark of senescence and neurodegenerative diseases including Alzheimer's disease (AD). However, it is not clear how DNase II and neuronal cytoplasmic dsDNA influence neuropathogenesis. Tau hyperphosphorylation is a key factor for the pathogenesis of AD. The effect of DNase II and neuronal cytoplasmic dsDNA on neuronal tau hyperphosphorylation remains unclarified. METHODS: The levels of neuronal DNase II and dsDNA in WT and Tau-P301S mice of different ages were measured by immunohistochemistry and immunolabeling, and the levels of DNase II in the plasma of AD patients were measured by ELISA. To investigate the impact of DNase II on tauopathy, the levels of phosphorylated tau, phosphokinase, phosphatase, synaptic proteins, gliosis and proinflammatory cytokines in the brains of neuronal DNase II-deficient WT mice, neuronal DNase II-deficient Tau-P301S mice and neuronal DNase II-overexpressing Tau-P301S mice were evaluated by immunolabeling, immunoblotting or ELISA. Cognitive performance was determined using the Morris water maze test, Y-maze test, novel object recognition test and open field test. RESULTS: The levels of DNase II were significantly decreased in the brains and the plasma of AD patients. DNase II also decreased age-dependently in the neurons of WT and Tau-P301S mice, along with increased dsDNA accumulation in the cytoplasm. The DNA accumulation induced by neuronal DNase II deficiency drove tau phosphorylation by upregulating cyclin-dependent-like kinase-5 (CDK5) and calcium/calmodulin activated protein kinase II (CaMKII) and downregulating phosphatase protein phosphatase 2A (PP2A). Moreover, DNase II knockdown induced and significantly exacerbated neuron loss, neuroinflammation and cognitive deficits in WT and Tau-P301S mice, respectively, while overexpression of neuronal DNase II exhibited therapeutic benefits. CONCLUSIONS: DNase II deficiency and cytoplasmic dsDNA accumulation can initiate tau phosphorylation, suggesting DNase II as a potential therapeutic target for tau-associated disorders.


Assuntos
Doença de Alzheimer , Endodesoxirribonucleases , Neurônios , Proteínas tau , Animais , Proteínas tau/metabolismo , Proteínas tau/genética , Fosforilação , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Doença de Alzheimer/patologia , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/deficiência , Endodesoxirribonucleases/metabolismo , Camundongos Transgênicos , DNA/genética , Masculino , Feminino , Encéfalo/metabolismo , Encéfalo/patologia , Camundongos Endogâmicos C57BL
13.
Ultrasound Q ; 40(3)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39105688

RESUMO

ABSTRACT: This study aims to explore the value of real-time strain elastography (RTE) and contrast-enhanced ultrasonography (CEUS) in the diagnosis of breast BI-RADS 4 lesions. It collected 85 cases (totaling 85 lesions) diagnosed with breast BI-RADS 4 through routine ultrasound from October 2020 to December 2022 in Huangshan City People's Hospital. All lesions underwent RTE and CEUS examination before surgery, and the ImageJ software was used to measure the periphery of lesion images in the enhancement peak mode and grayscale mode to calculate the contrast-enhanced ultrasound area ratio. The diagnostic capabilities of single-modal and multimodal ultrasound examination for the malignancy of breast BI-RADS 4 lesions were compared using the receiver operating characteristic curve; the Spearman correlation analysis was adopted to evaluate the correlation between multimodal ultrasound and CEUS area ratio. As a result, among the 85 lesions, 51 were benign, and 34 were malignant. The areas under the curve (AUCs) of routine ultrasound (US), US + RTE, US + CEUS, and US + RTE + CEUS were 0.816, 0.928, 0.953, and 0.967, respectively, with the combined method showing a higher AUC than the single application. The AUC of the CEUS area ratio diagnosing breast lesions was 0.888. There was a strong positive correlation (r = 0.819, P < 0.001) between the diagnostic performance of US + RTE + CEUS and the CEUS area ratio. In conclusion, based on routine ultrasound, the combination of RTE and CEUS can further improve the differential diagnosis of benign and malignant lesions in breast BI-RADS 4.


Assuntos
Neoplasias da Mama , Mama , Meios de Contraste , Técnicas de Imagem por Elasticidade , Ultrassonografia Mamária , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Pessoa de Meia-Idade , Diagnóstico Diferencial , Adulto , Técnicas de Imagem por Elasticidade/métodos , Mama/diagnóstico por imagem , Imagem Multimodal/métodos , Idoso , Reprodutibilidade dos Testes , Adulto Jovem , Aumento da Imagem/métodos
14.
Food Chem ; 460(Pt 3): 140713, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39116775

RESUMO

Chitosan, as a kind of naturally occurring green and degradable material for the preservation of perishable foods, was investigated in this study with the objective of enhancing its preservation performances. Herein, lignin was modified using the solvent fractionation method (modified lignin, ML, including ML1-ML3), while natural clinoptilolite zeolite was modified using the alkali modification method (modified clinoptilolite zeolite, MCZ, including MCZ1-MCZ5). After optimizing the conditions, it was discovered that incorporating both ML3 and MCZ3 into pure chitosan-based membranes might be conducive to fabricate chitosan-based composite membranes for the preservation of perishable foods. As-prepared composite membranes possessed better visible light transmittance, antioxidant activity, and carbon dioxide/oxygen selectivity, resulting in improved preservation effects on the model perishable foods such as bananas, cherry tomatoes, and cheeses. These findings might indicate promising applications for chitosan-based composite membranes with modified lignin and zeolite in the field of eco-friendly degradable materials for the preservation of perishable foods.

15.
J Am Chem Soc ; 146(32): 22405-22412, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39099103

RESUMO

While the majority of knots are made from the metal-template approach, the use of entangled, constrained knotted loops to modulate the coordination of the metal ions remains inadequately elucidated. Here, we report on the coordination chemistry of a 140-atom-long cinquefoil knotted strand comprising five tridentate and five bidentate chelating vacancies. The knotted loop is prepared through the self-assembly of asymmetric "3 + 2" dentate ligands with copper(II) ions that favor five-coordination geometry. The formation of the copper(II) pentameric helicate is confirmed by X-ray crystallography, while the corresponding copper(II) knot is characterized by XPS and LR-/HR ESI-MS. Upon removal of the original template, the knotted ligand facilitates zinc(II) ions, which typically form four- or six-coordination geometries, resulting in the formation of an otherwise inaccessible zinc(II) metallic knot with coordinatively unsaturated metal centers. The coordination numbers and geometries of the zinc(II) cations are undoubtedly determined by X-ray crystallography. Despite the kinetically labile nature and high reversibility of the zinc(II) complex preventing the detection of 5-to-6 coordination equilibrium in solution, the effects on metal-ion coordination induced by knotting hold promise for fine-tuning the coordination of metal complexes.

16.
Adv Mater ; : e2400166, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39049804

RESUMO

Anomalous Hall effect (AHE), one of the most important electronic transport phenomena, generally appears in ferromagnetic materials but is rare in materials without magnetic elements. Here, a study of La3MgBi5 is presented, whose band structure carries multitype Dirac fermions. Although magnetic elements are absent in La3MgBi5, the signals of AHE can be observed. In particular, the anomalous Hall conductivity is extremely large, reaching 42,356 Ω-1 cm-1 with an anomalous Hall angle of 8.8%, the largest one that has been observed in the current AHE systems. The AHE is suggested to originate from the combination of skew scattering and Berry curvature. Another unique property discovered in La3MgBi5 is the axial diamagnetism. The diamagnetism is significantly enhanced and dominates the magnetization in the axial directions, which is the result of the restricted motion of the Dirac fermion at the Fermi level. These findings not only establish La3MgBi5 as a suitable platform to study AHE and quantum transport but also indicate the great potential of 315-type Bi-based materials for exploring novel physical properties.

17.
Diabetes Metab Syndr Obes ; 17: 2789-2807, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39072347

RESUMO

Metabolic reprogramming contributes to the progression and prognosis of various kidney diseases. Glutamine is the most abundant free amino acid in the body and participates in more metabolic processes than other amino acids. Altered glutamine metabolism is a prominent feature in different kidney diseases. Glutaminolysis converts glutamine into the TCA cycle metabolite, alpha-ketoglutarate, via a cascade of enzymatic reactions. This metabolic pathway plays pivotal roles in inflammation, maladaptive repair, cell survival and proliferation, redox homeostasis, and immune regulation. Given the crucial role of glutaminolysis in bioenergetics and anaplerotic fluxes in kidney pathogenesis, studies on this cascade could provide a better understanding of kidney diseases, thus inspiring the development of potential methods for targeted therapy. Emerging evidence has shown that targeting glutaminolysis is a promising therapeutic strategy for ameliorating kidney disease. In this narrative review, equation including keywords related to glutamine, glutaminolysis and kidney are subjected to an exhaustive search on Pubmed database, we identified all relevant articles published before 1 April, 2024. Afterwards, we summarize the regulation of glutaminolysis in major kidney diseases and its underlying molecular mechanisms. Furthermore, we highlight therapeutic strategies targeting glutaminolysis and their potential clinical applications.

18.
J Am Chem Soc ; 146(30): 20963-20971, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39031612

RESUMO

In the realm of nanoscale materials design, achieving precise control over the dimensions of nanotubular architectures poses a substantial challenge. In our ongoing pursuit, we have successfully engineered a novel class of single-molecule nanotubes─isoreticular covalent organic pillars (iCOPs)─by stacking formylated macrocycles through multiple dynamic covalent imine bonds, guided by principles of reticular chemistry. Our strategic selection of rigid diamine linkers has facilitated the synthesis of a diverse array of iCOPs, each retaining a homologous structure yet offering distinct cavity shapes influenced by the linker choice. Notably, three of these iCOP variants feature continuous one-dimensional channels, exhibiting length-dependent host-guest interactions with α,ω-dibromoalkanes, and each presenting a distinct critical guest alkyl chain length threshold for efficient guest encapsulation. This newfound capability not only provides a platform for tailoring nanotubular structures with precision, but also opens new avenues for innovative applications in molecular recognition and the purification of complex mixtures.

19.
Molecules ; 29(14)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39065007

RESUMO

The oxidation of benzylic alcohols is an important transformation in modern organic synthesis. A plethora of photoredox protocols have been developed to achieve the aerobic oxidation of alcohols into carbonyls. Recently, several groups described that ultraviolet (UV) or purple light can initiate the aerobic oxidation of benzylic alcohols in the absence of an external catalyst, and depicted different mechanisms involving the photoinduction of •O2- as a critical reactive oxygen species (ROS). However, based on comprehensive mechanistic investigations, including control experiments, radical quenching experiments, EPR studies, UV-vis spectroscopy, kinetics studies, and density functional theory calculations (DFT), we elucidate here that HOO•, which is released via the H2O2 elimination of α-hydroxyl peroxyl radicals [ArCR(OH)OO•], serves as the real chain carrier for the autocatalytic photooxidation of benzylic alcohols. The mechanistic ambiguities depicted in the precedent literature are clarified, in terms of the crucial ROS and its evolution, the rate-limiting step, and the primary radical cascade. This work highlights the necessity of stricter mechanistic analyses on UV-driven oxidative reactions that involve aldehydes' (or ketones) generation.

20.
Sensors (Basel) ; 24(14)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39065918

RESUMO

Ultrasonic flow meters are crucial measuring instruments in natural gas transportation pipeline scenarios. The collected flow velocity data, along with the operational conditions data, are vital for the analysis of the metering performance of ultrasonic flow meters and analysis of the flow process. In practical applications, high requirements are placed on the modeling accuracy of ultrasonic flow meters. In response, this paper proposes an ultrasonic flow meter modeling method based on a combination of data learning and industrial physics knowledge. This paper builds ultrasonic flow meter flow velocity prediction models under different working conditions, combining pipeline flow field velocity distribution knowledge for data preprocessing and loss function design. By making full use of the characteristics of the physics and data learning, the prediction results are close to the real acoustic path flow velocity distribution; thus, the model has high accuracy and interpretability. Experiments are conducted to prove that the prediction error of the proposed method can be controlled within 1%, which can meet the needs of ultrasonic flow meter modeling and subsequent performance analysis in actual production.

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