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1.
Nat Chem ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304724

RESUMO

Boron dipyrromethenes (BODIPYs) are some of the most popular and indispensable tetracoordinate boron compounds and have found widespread applications owing to their excellent spectroscopic and photophysical properties. BODIPYs possessing boron-stereogenic centres are scarce, and strategies for the synthesis of enantioenriched boron-stereogenic BODIPYs with structural diversity remain underdeveloped. In theory, the BODIPY core skeleton has several sites that could be decorated with different substituents. However, due to the lack of general and efficient asymmetric synthetic methods, this potential diversity of chiral BODIPYs has not been exploited. Here we demonstrate a modular enantioselective assembly of multi-substituted boron-stereogenic BODIPYs in high efficiency with excellent enantioselectivities. Key to the success is the Pd-catalysed desymmetric Suzuki cross-coupling, enabling the precise discrimination of the two α C-Cl bonds of the designed prochiral BODIPY scaffold, giving access to a wide range of highly functionalized boron-stereogenic BODIPYs. Derivatizations, photophysical properties and applications in chiral recognition of the obtained optical BODIPYs are further explored.

2.
Front Pharmacol ; 15: 1433030, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39281281

RESUMO

Alzheimer's disease (AD) is a complex neurodegenerative disease that affects elderly individuals, characterized by senile plaques formed by extracellular amyloid beta (Aß). Autophagy dysfunction is a manifestation of protein homeostasis imbalance in patients with AD, but its relationship with Aß remains unclear. Here, we showed that in Aß transgenic Caenorhabditis elegans, Aß activated the TOR pathway and reduced the nuclear entry of HLH-30, leading to autophagy dysfunction characterized by autophagosome accumulation. Then, utilizing RNA-seq, we investigated the regulatory mechanisms by which HLH-30 modulates autophagy in C. elegans. We found that HLH-30 elevated the transcript levels of v-ATPase and cathepsin, thus enhancing lysosomal activity. This led to an increase in autophagic flux, facilitating more pronounced degradation of Aß. Moreover, HLH-30 reduced the level of ROS induction by Aß and enhanced the antioxidant stress capacity of the worms through the gsto-1 gene. Additionally, we identified two HLH-30/TFEB activators, saikosaponin B2 and hypericin, that improved autophagic flux, thereby enhancing protein homeostasis in C. elegans. Overall, our findings suggested that HLH-30/TFEB plays a key role in modulating autophagy and can be considered a promising drug target for AD treatments.

3.
Antioxidants (Basel) ; 13(9)2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39334745

RESUMO

The improvement of mitochondrial function is described as a strategy for alleviating oxidative stress and intervening in the aging process. 2,3,5,4'-Tetrahydroxystilbene-2-O-ß-D-glucoside (TSG) is one of the major bioactive components isolated from Polygonum multiflorum Thunb, and it exhibits multiple activities, including antioxidant and anti-inflammatory effects. In this study, we found that 200 µM TSG significantly extended the mean lifespan of Caenorhabditis elegans by 16.48% and improved health status by delaying age-associated physiological decline in worms. The longevity prolongation effect of TSG depended on the regulation of the mitochondrial quality control process mediated by DAF-16/FOXO, SKN-1/Nrf2 and SIR-2.1/SIRT1 to improve mitochondrial function. Moreover, TSG treatment obviously alleviated the proteotoxicity of ß-amyloid and tau proteins in worms. Our findings indicated that TSG is a promising natural product for preventing aging and treating aging-associated neurodegenerative diseases by regulating the mitochondrial quality control process to improve mitochondrial function.

4.
Compos B Eng ; 2832024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39071449

RESUMO

Periodontitis is a highly prevalent disease that damages the supporting tissues of a tooth, including the alveolar bone. Alveolar bone loss owing to periodontitis is broadly categorized as supra-alveolar and intra-alveolar bone loss. In intra-alveolar bone loss, the defect has an angular or oblique orientation to the long axis of the tooth in an apical direction. In contrast, the defect is perpendicular to the long axis of the tooth in supra-alveolar bone loss. Unlike intra-alveolar bone defects, supra-alveolar bone defects lack supporting adjacent space, which makes supra-alveolar bone regeneration more challenging. In addition, the limited availability of resources in terms of vascularity and underlying tissues is another obstacle to supra-alveolar bone regeneration. Currently, supra-alveolar bone loss is the least predictable periodontal defect type in regenerative periodontal therapy. In addition, supra-alveolar bone loss is much more common than other alveolar bone loss. Despite its prevalence, research on supra-alveolar bone regeneration remains sparse, indicating an unmet need for significant research efforts in this area. This review summarize recent advances, obstacles, and future directions in the field of supra-alveolar bone regeneration. We discuss the biomaterials, bioactive molecules, and cells that have been tested for supra-alveolar bone regeneration, followed by pre-clinical and clinical approaches employed in this field. Additionally, we highlight obstacles and present future directions that will propel supra-alveolar bone research forward.

5.
Indian J Ophthalmol ; 72(8): 1175-1180, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39078962

RESUMO

PURPOSE: To analyze the characteristics of optical coherence tomography in acute macular neuroretinopathy (AMN) following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and discuss the prognostic predictors. METHODS: Patients with AMN following SARS-CoV-2 infection were divided into two groups according to the presence or absence of hyperreflective outer nuclear layer (ONL) lesion involving the fovea. RESULTS: The first visit included 14 eyes in the fovea-involved group and 20 eyes in the no fovea-involved group. Ellipsoid zone (EZ) hyporeflection and interdigitation zone (IZ) interruption were detected in all eyes. Other common manifestations were myoid zone (MZ) hyperreflection (76.5%), ONL hyperreflection (73.5%), outer plexiform layer (OPL) thickening (64.7%), and EZ interruption (50%). The follow-up period was 48.4 ± 55.3 days. At the last visit, 12 eyes were in the fovea-involved group and 13 eyes in the no fovea-involved group. IZ interruption was detected in all eyes. Other common manifestations were EZ hyporeflection (92.0%), ONL atrophy (40.0%), OPL thickening (36.0%), OPL linear (32.0%), and MZ hyperreflection (32%). The improvement of visual acuity (VA) was -0.5 ± 0.5 and -0.2 ± 0.4 in the fovea-involved group and the no fovea-involved group, respectively, with a statistically significant difference between them (P = 0.045). Initial VA, initial cotton wool spot, initial ONL cyst, final ONL cyst, and final OPL linear were associated with final VA (P = 0.000, P = 0.029, P = 0.044, P = 0.049, P = 0.049, respectively). CONCLUSIONS: In the early stage of AMN following SARS-CoV-2 infection, IZ interruption and EZ hyporeflection were the most common manifestations, and pathology of IZ was more serious than that of EZ. Subsequently, OPL and ONL atrophied, and ONL atrophied faster. Regardless of whether hyperreflective ONL involved the fovea, VA improved, with a more noticeable improvement found in the fovea-involved group. The presence of initial ONL cyst and initial cotton wool spot, rapid atrophy of OPL, and poorer initial VA indicating poorer VA outcome.


Assuntos
COVID-19 , SARS-CoV-2 , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Tomografia de Coerência Óptica/métodos , COVID-19/complicações , COVID-19/diagnóstico , Masculino , Feminino , Prognóstico , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Doença Aguda , Doenças Retinianas/diagnóstico , Doenças Retinianas/etiologia , Macula Lutea/patologia , Macula Lutea/diagnóstico por imagem , Seguimentos
7.
Artigo em Inglês | MEDLINE | ID: mdl-39038320

RESUMO

Objective: This study aimed to search and analyze relevant evidence on perioperative activities in patients undergoing hepatectomy and provide a summary of the best evidence available. Methods: Comprehensive computer searches were conducted in various databases, including PubMed, Cochrane Library, BMJ Best Practice, Joanna Briggs Institute, Evidence-Based Health Care Centre Database, US Guidelines Network, UK National Institute of Clinical Medicine, Scottish Intercollegiate Guidelines Network, International Guidelines Association Network, New Zealand Clinical Practice Guidelines Network, and Chinese Biomedical Literature Database from January 30, 2022 to December 30, 2023. The search included guidelines, expert consensus, evidence summaries, systematic reviews, and original research closely related to the evidence. Results: A total of 11 pieces of evidence were included, consisting of 2 guidelines, 2 expert consensuses, 1 evidence summary, 1 systematic review, and 5 randomized controlled trials (RCTs). From these, five pieces of best evidence were identified. Conclusions: The evidence from the included studies collectively indicates that well-planned perioperative activities are safe and beneficial for patients undergoing hepatectomy. Furthermore, high-quality local guidelines have been established in China, suggesting that healthcare professionals can adopt these practices to accelerate patient recovery and enhance the quality of clinical care.

8.
Int J Rheum Dis ; 27(7): e15255, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38982881

RESUMO

BACKGROUND: The Oxidative Balance Score (OBS) is a systematic tool to assess the effects of diet and lifestyle in relation to oxidative stress. The association between OBS and gout has not been reported previously. We conducted a cross-sectional study to investigate the complex association between OBS and gout in US adults. METHODS: In all, 10 492 participants were included in this study. The exposure variable was OBS, which was scored by 16 dietary and four lifestyle factors. Multivariate logistic regression, subgroup analysis, and restricted cubic spline (RCS) regression were used to analyze the association between OBS and gout. RESULTS: Compared with the lowest OBS quartile group (Q1), the multivariate corrected odds ratio (OR) (95% confidence interval [C]) for the highest quartile of OBS (Q4) was 0.72 (0.52-1.00) (p = .13 for trend); furthermore, the RCS showed a negative linear relationship between OBS and gout (p-nonlinear = .606). CONCLUSION: In conclusion, the risk of gout is higher with high OBS. The prevalence of gout decreased with higher OBS. Diabetes may alter this negative correlation.


Assuntos
Gota , Inquéritos Nutricionais , Estresse Oxidativo , Humanos , Gota/epidemiologia , Gota/diagnóstico , Estudos Transversais , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Estados Unidos/epidemiologia , Adulto , Prevalência , Estilo de Vida , Medição de Risco , Dieta/efeitos adversos , Idoso
9.
J Immunother Cancer ; 12(6)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886114

RESUMO

BACKGROUND: Epstein-Barr virus (EBV) is a double-stranded DNA oncogenic virus. Several types of solid tumors, such as nasopharyngeal carcinoma, EBV-associated gastric carcinoma, and lymphoepithelioma-like carcinoma of the lung, have been linked to EBV infection. Currently, several TCR-T-cell therapies for EBV-associated tumors are in clinical trials, but due to the suppressive immune microenvironment of solid tumors, the clinical application of TCR-T-cell therapy for EBV-associated solid tumors is limited. Figuring out the mechanism by which EBV participates in the formation of the tumor immunosuppressive microenvironment will help T cells or TCR-T cells break through the limitation and exert stronger antitumor potential. METHODS: Flow cytometry was used for analyzing macrophage differentiation phenotypes induced by EBV-infected and EBV-uninfected tumors, as well as the function of T cells co-cultured with these macrophages. Xenograft model in mice was used to explore the effects of M2 macrophages, TCR-T cells, and matrix metalloprotein 9 (MMP9) inhibitors on the growth of EBV-infected tumors. RESULTS: EBV-positive tumors exhibited an exhaustion profile of T cells, despite the presence of a large T-cell infiltration. EBV-infected tumors recruited a large number of mononuclear macrophages with CCL5 and induced CD163+M2 macrophages polarization through the secretion of CSF1 and the promotion of autocrine IL10 production by mononuclear macrophages. Massive secretion of MMP9 by this group of CD163+M2 macrophages induced by EBV infection was an important factor contributing to T-cell exhaustion and TCR-T-cell therapy resistance in EBV-positive tumors, and the use of MMP9 inhibitors improved the function of T cells cocultured with M2 macrophages. Finally, the combination of an MMP9 inhibitor with TCR-T cells targeting EBV-positive tumors significantly inhibited the growth of xenografts in mice. CONCLUSIONS: MMP9 inhibitors improve TCR-T cell function suppressed by EBV-induced M2 macrophages. TCR-T-cell therapy combined with MMP9 inhibitors was an effective therapeutic strategy for EBV-positive solid tumors.


Assuntos
Antígenos CD , Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Macrófagos , Metaloproteinase 9 da Matriz , Receptores de Superfície Celular , Animais , Camundongos , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Receptores de Superfície Celular/metabolismo , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Microambiente Tumoral , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Feminino , Linfócitos T/imunologia , Linfócitos T/metabolismo , Imunoterapia Adotiva/métodos
10.
Beilstein J Nanotechnol ; 15: 694-703, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919165

RESUMO

Multifrequency atomic force microscopy (AFM) utilizes the multimode operation of cantilevers to achieve rapid high-resolution imaging and extract multiple properties. However, the higher-order modal response of traditional rectangular cantilever is weaker in air, which affects the sensitivity of multifrequency AFM detection. To address this issue, we previously proposed a bridge/cantilever coupled system model to enhance the higher-order modal response of the cantilever. This model is simpler and less costly than other enhancement methods, making it easier to be widely used. However, previous studies were limited to theoretical analysis and preliminary simulations regarding ideal conditions. In this paper, we undertake a more comprehensive investigation of the coupled system, taking into account the influence of probe and excitation surface sizes on the modal response. To facilitate the exploration of the effectiveness and optimal conditions for the coupled system in practical applications, a macroscale experimental platform is established. By conducting finite element analysis and experiments, we compare the performance of the coupled system with that of traditional cantilevers and quantify the enhancement in higher-order modal response. Also, the optimal conditions for the enhancement of macroscale cantilever modal response are explored. Additionally, we also supplement the characteristics of this model, including increasing the modal frequency of the original cantilever and generating additional resonance peaks, demonstrating the significant potential of the coupled system in various fields of AFM.

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