Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 481
Filtrar
Más filtros

Intervalo de año de publicación
1.
Trends Biotechnol ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39237385

RESUMEN

The understanding of cellular energy metabolism activation by engineered scaffolds remains limited, posing challenges for therapeutic applications in tissue regeneration. This study presents biosynthesized poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] and its major degradation product, 3-hydroxybutyrate (3HB), as endogenous bioenergetic fuels that augment cellular anabolism, thereby facilitating the progression of human bone marrow-derived mesenchymal stem cells (hBMSCs) towards osteoblastogenesis. Our research demonstrated that 3HB markedly boosts in vitro ATP production, elevating mitochondrial membrane potential and capillary-like tube formation. Additionally, it raises citrate levels in the tricarboxylic acid (TCA) cycle, facilitating the synthesis of citrate-containing apatite during hBMSCs osteogenesis. Furthermore, 3HB administration significantly increased bone mass in rats with osteoporosis induced by ovariectomy. The findings also showed that P(3HB-co-4HB) scaffold substantially enhances long-term vascularized bone regeneration in rat cranial defect models. These findings reveal a previously unknown role of 3HB in promoting osteogenesis of hBMSCs and highlight the metabolic activation of P(3HB-co-4HB) scaffold for bone regeneration.

2.
J Thorac Oncol ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39306192

RESUMEN

INTRODUCTION: An increasing number of early-stage lung adenocarcinoma (LUAD) are detected as lung nodules. The radiological features related to LUAD progression remain further investigation. Exploration is required to bridge the gap between radiomics features and molecular characteristics of lung nodules. METHODS: Consensus clustering was applied to the radiomics features of 1,212 patients to establish stable clustering. Clusters were illustrated using clinicopathological and next-generation sequencing (NGS). A classifier was constructed to further investigate the molecular characteristic in patients with paired CT and RNA-seq data. RESULTS: Patients were clustered into 4 clusters. Cluster 1 was associated with a low consolidation-to-tumor ratio (CTR), pre-invasion, grade I disease and good prognosis. Clusters 2 and 3 showed increasing malignancy with higher CTR, higher pathological grade and poor prognosis. Cluster 2 possessed more spread through air spaces (STAS) and cluster 3 showed higher proportion of pleural invasion. Cluster 4 had similar clinicopathological features with cluster 1 except higher proportion of grade II disease. RNA-seq indicated that cluster 1 represented nodules with indolent growth and good differentiation, whereas cluster 4 showed progression in cell development but still had low proliferative activity. Nodules with high proliferation were classified into clusters 2 and 3. Additionally, the radiomics classifier distinguished cluster 2 as nodules harboring an activated immune environment, while cluster 3 represented nodules with a suppressive immune environment. Furthermore, gene signatures associated with the prognosis of early-stage LUAD were validated in external datasets. CONCLUSION: Radiomics features can manifest molecular events driving progression of lung adenocarcinoma. Our study provides a molecular insight into radiomics features and assists in the diagnosis and treatment of early stage LUAD.

3.
Int J Biol Macromol ; 280(Pt 2): 135870, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39307493

RESUMEN

Dicentrinone (Di), liriodenine (Li) and lysicamine (Ly) are three natural oxoaporphine alkaloids (OAs), which revealed significant biological activity such as anticancer, anti-inflammatory and antimicrobial activities and were considered as potential lead compounds for the development of new clinical chemicals. In the present study, confocal laser scanning fluorescence microscopy observation demonstrated these three natural OAs could traverse inside of the nucleus and get an opportunity to interact with DNA. Their interaction properties with DNA were then investigated simultaneously by two spectral fluorescent probes of ethidium bromide (EB) and methyl green (MG), as well as UV-vis absorption and cyclic voltammetry measurements, and further verified by the molecular docking analysis. Results indicated Di and Li were distinctly classified as the intercalative molecules to DNA, however, Ly was confirmed with a mixed-mode binding of partial intercalation and groove affinity. Their binding ability was revealed as the follows: Di ≥ Li > Ly, which was correlated with their structural changes. Thermodynamic studies revealed the binding process of Li and Ly with ctDNA was all spontaneous, the hydrophobic interaction was the major binding force for Li-ctDNA complex, however, the interaction between Ly and ctDNA relied on both hydrophobic and hydrogen binding force. Molecular docking provided detailed computational interaction of Di, Li and Ly with DNA, which proved the intercalation binding of Li-DNA complex and Di-DNA complex stabilizing mainly by the π-π binding force, however, apart from a small quantity of π-π interaction, another binding force in the Ly-DNA complex mainly was supplied from the weaker Pi-Alkyl, hydrogen bond and Pi-Anion interactions.

4.
Methods Mol Biol ; 2841: 85-94, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39115767

RESUMEN

The plant cell wall is rich in polysaccharides with high heterogeneity. Investigating the composition and structure of cell wall polysaccharides is crucial for understanding the functionalities of plant cell walls. Carbohydrate electrophoresis is a sensitive and rapid method to analyze polysaccharides qualitatively and quantitatively. The process includes digesting the polysaccharides with appropriate cleavage enzymes, labeling the reducing ends of the released oligosaccharides with a highly charged fluorophore, and separating the labeled oligosaccharides in a polyacrylamide gel via high-voltage electrophoresis. The generated fluorescence can be calculated as compared to that of oligosaccharide standards. Therefore, this is a convenient method for polysaccharide characterization that can be performed in most laboratories. Here, we introduce the detailed operational steps and precautions, which are helpful for researchers to quickly obtain the structural information of polysaccharides.


Asunto(s)
Pared Celular , Polisacáridos , Pared Celular/química , Polisacáridos/análisis , Polisacáridos/química , Oligosacáridos/análisis , Oligosacáridos/química , Electroforesis en Gel de Poliacrilamida/métodos , Electroforesis/métodos
5.
Phys Rev Lett ; 133(6): 060201, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39178451

RESUMEN

Bell's theorem states that the quantum mechanical description of physical quantities cannot be fully explained by local realistic theories, laying a solid basis for various quantum information applications. Hardy's paradox is celebrated as the simplest form of Bell's theorem concerning its "All versus Nothing" approach to test local realism. However, due to experimental imperfections, existing tests of Hardy's paradox require additional assumptions of the experimental systems, and these assumptions constitute potential loopholes for faithfully testing local realistic theories. Here, we experimentally demonstrate Hardy's nonlocality through a photonic entanglement source. By achieving a detection efficiency of 82.2%, a quantum state fidelity of 99.10%, and applying high-speed quantum random number generators for the measurement setting switching, the experiment is implemented in a loophole-free manner. During 6 h of running, a strong violation of P_{Hardy}=4.646×10^{-4} up to 5 standard deviations is observed with 4.32×10^{9} trials. A null hypothesis test shows that the results can be explained by local realistic theories with an upper bound probability of 10^{-16348}. These testing results provide affirmative evidence against local realism, and establish an advancing benchmark for quantum information applications based on Hardy's paradox.

6.
Cell Rep ; 43(8): 114613, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39116206

RESUMEN

Leptomeningeal metastases (LMs) remain a devastating complication of non-small cell lung cancer (NSCLC), particularly following osimertinib resistance. We conducted single-cell RNA sequencing on cerebrospinal fluid (CSF) from EGFR-mutant NSCLC with central nervous system metastases. We found that macrophages of LMs displayed functional and phenotypic heterogeneity and enhanced immunosuppressive properties. A population of lipid-associated macrophages, namely RNASE1_M, were linked to osimertinib resistance and LM development, which was regulated by Midkine (MDK) from malignant epithelial cells. MDK exhibited significant elevation in both CSF and plasma among patients with LMs, with higher MDK levels correlating to poorer outcomes in an independent cohort. Moreover, MDK could promote macrophage M2 polarization with lipid metabolism and phagocytic function. Furthermore, malignant epithelial cells in CSF, particularly after resistance to osimertinib, potentially achieved immune evasion through CD47-SIRPA interactions with RNASE1_M. In conclusion, we revealed a specific subtype of macrophages linked to osimertinib resistance and LM development, providing a potential target to overcome LMs.


Asunto(s)
Acrilamidas , Compuestos de Anilina , Carcinoma de Pulmón de Células no Pequeñas , Resistencia a Antineoplásicos , Neoplasias Pulmonares , Macrófagos , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/tratamiento farmacológico , Compuestos de Anilina/farmacología , Compuestos de Anilina/uso terapéutico , Acrilamidas/farmacología , Acrilamidas/uso terapéutico , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Animales , Ratones , Línea Celular Tumoral , Femenino , Carcinomatosis Meníngea/tratamiento farmacológico , Carcinomatosis Meníngea/patología , Carcinomatosis Meníngea/secundario , Metabolismo de los Lípidos/efectos de los fármacos , Antígeno CD47/metabolismo , Antígeno CD47/genética , Masculino , Fagocitosis/efectos de los fármacos , Receptores ErbB/metabolismo , Receptores ErbB/genética , Indoles , Pirimidinas
7.
J Thorac Dis ; 16(6): 3828-3843, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38983152

RESUMEN

Background: Ground-glass nodule (GGN) is the most common manifestation of lung adenocarcinoma on computed tomography (CT). Clinically, the success rate of preoperative diagnosis of GGN by puncture biopsy and other means is still low. The aim of this study is to investigate the clinical and radiomics characteristics of lung adenocarcinoma presenting as GGN on CT images using radiomics analysis methods, establish a radiomics model, and predict the classification of pathological tissue and instability of GGN type lung adenocarcinoma. Methods: This study retrospectively collected 249 patients with 298 GGN lesions who were pathologically confirmed of having lung adenocarcinoma. The images were imported into the Siemens scientific research prototype software to outline the region of interest and extract the radiomics features. Logistic model A (a radiomics model to identify the infiltration of lung adenocarcinoma manifesting as GGNs) was established using features after the dimensionality reduction process. The receiver operating characteristic (ROC) curve of the model on training set and the verification set was drawn, and the area under the curve (AUC) was calculated. Second, a total of 112 lesions were selected from 298 lesions originating from CT images of at least two occasions, and the time between the first CT and the preoperative CT was defined as not less than 90 days. The mass doubling time (MDT) of all lesions was calculated. According to the different MDT diagnostic thresholds instability was predicted. Finally, their AUCs were calculated and compared. Results: There were statistically significant differences in age and lesion location distribution between the "noninvasive" lesion group and the invasive lesion group (P<0.05), but there were no statistically significant differences in sex (P>0.05). Model A had an AUC of 0.89, sensitivity of 0.75, and specificity of 0.86 in the training set and an AUC of 0.87, sensitivity of 0.63, and specificity of 0.90 in the validation set. There was no significant difference statistically in MDT between "noninvasive" lesions and invasive lesions (P>0.05). The AUCs of radiomics models B1, B2 and B3 were 0.89, 0.80, and 0.81, respectively; the sensitivities were 0.71, 0.54, and 0.76, respectively; the specificities were 0.83, 0.77, and 0.60, respectively; and the accuracies were 0.78, 0.65, and 0.69, respectively. Conclusions: There were statistically significant differences in age and location of lesions between the "noninvasive" lesion group and the invasive lesion group. The radiomics model can predict the invasiveness of lung adenocarcinoma manifesting as GGNs. There was no significant difference in MDT between "noninvasive" lesions and invasive lesions. The radiomics model can predict the instability of lung adenocarcinoma manifesting as GGN. When the threshold of MDT was set at 813 days, the model had higher specificity, accuracy, and diagnostic efficiency.

8.
Cell Rep Med ; 5(7): 101615, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38897205

RESUMEN

The clinical efficacy of neoadjuvant immunotherapy plus chemotherapy remains elusive in localized epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). Here, we report interim results of a Simon's two-stage design, phase 2 trial using neoadjuvant sintilimab with carboplatin and nab-paclitaxel in resectable EGFR-mutant NSCLC. All 18 patients undergo radical surgery, with one patient experiencing surgery delay. Fourteen patients exhibit confirmed radiological response, with 44% achieving major pathological response (MPR) and no pathological complete response (pCR). Similar genomic alterations are observed before and after treatment without influencing the efficacy of subsequent EGFR-tyrosine kinase inhibitors (TKIs) in vitro. Infiltration and T cell receptor (TCR) clonal expansion of CCR8+ regulatory T (Treg)hi/CXCL13+ exhausted T (Tex)lo cells define a subtype of EGFR-mutant NSCLC highly resistant to immunotherapy, with the phenotype potentially serving as a promising signature to predict immunotherapy efficacy. Informed circulating tumor DNA (ctDNA) detection in EGFR-mutant NSCLC could help identify patients nonresponsive to neoadjuvant immunochemotherapy. These findings provide supportive data for the utilization of neoadjuvant immunochemotherapy and insight into immune resistance in EGFR-mutant NSCLC.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma de Pulmón de Células no Pequeñas , Receptores ErbB , Neoplasias Pulmonares , Mutación , Terapia Neoadyuvante , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Receptores ErbB/genética , Terapia Neoadyuvante/métodos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Femenino , Masculino , Persona de Mediana Edad , Anciano , Mutación/genética , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Paclitaxel/uso terapéutico , Carboplatino/uso terapéutico , Adulto , Resultado del Tratamiento , ADN Tumoral Circulante/genética , Albúminas
9.
Polymers (Basel) ; 16(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38932039

RESUMEN

Metallocene catalysts have attracted much attention from academia and industry for their excellent catalytic activity in the field of olefin polymerization. Cocatalysts play a key role in metallocene catalytic systems, which can not only affect the overall catalytic activity, but also have an obvious influence on the structure and properties of the polymer. Although methylaluminoxane (MAO) is currently the most widely used cocatalyst, its price increases the production cost of polyolefin materials. Ammonium tetrakis(pentafluorophenyl)borate has shown excellent performance in polymerization, being one of the best substitutes for the traditional cocatalyst MAO. Compared with the main catalyst, whose composition and structure are relatively complex, the research on cocatalyst is very limited. This review mainly introduces the research history, preparation methods, and application progress in polymerization of ammonium tetrakis(pentafluorophenyl)borate, deepening our understanding of the role of cocatalyst in polymerization, with the hope of inspiring brand-new thinking on improving and enhancing the overall performance of catalyst systems.

10.
ACS Nano ; 18(24): 15452-15467, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38830624

RESUMEN

Type 2 diabetes (T2D), a prevalent metabolic disorder lacking effective treatments, is associated with lysosomal acidification dysfunction, as well as autophagic and mitochondrial impairments. Here, we report a series of biodegradable poly(butylene tetrafluorosuccinate-co-succinate) polyesters, comprising a 1,4-butanediol linker and varying ratios of tetrafluorosuccinic acid (TFSA) and succinic acid as components, to engineer lysosome-acidifying nanoparticles (NPs). The synthesized NPs are spherical with diameters of ≈100 nm and have low polydispersity and good stability. Notably, TFSA NPs, which are composed entirely of TFSA, exhibit the strongest degradation capability and superior acidifying properties. We further reveal significant downregulation of lysosomal vacuolar (H+)-ATPase subunits, which are responsible for maintaining lysosomal acidification, in human T2D pancreatic islets, INS-1 ß-cells under chronic lipotoxic conditions, and pancreatic tissues of high-fat-diet (HFD) mice. Treatment with TFSA NPs restores lysosomal acidification, autophagic function, and mitochondrial activity, thereby improving the pancreatic function in INS-1 cells and HFD mice with lipid overload. Importantly, the administration of TFSA NPs to HFD mice reduces insulin resistance and improves glucose clearance. These findings highlight the therapeutic potential of lysosome-acidifying TFSA NPs for T2D.


Asunto(s)
Células Secretoras de Insulina , Lisosomas , Nanopartículas , Lisosomas/metabolismo , Lisosomas/efectos de los fármacos , Animales , Nanopartículas/química , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Ratones , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/patología , Masculino , Dieta Alta en Grasa , Ratones Endogámicos C57BL , Concentración de Iones de Hidrógeno
11.
ACS Appl Mater Interfaces ; 16(25): 32357-32366, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38877995

RESUMEN

Metal-semiconductor junctions play an important role in the development of electronic and optoelectronic devices. A Schottky junction photodetector based on two-dimensional (2D) materials is promising for self-powered photodetection with fast response speed and large signal-to-noise ratio. However, it usually suffers from an uncontrolled Schottky barrier due to the Fermi level pinning effect arising from the interface states. In this work, all-2D Schottky junctions with near-ideal Fermi level depinning are realized, attributed to the high-quality interface between 2D semimetals and semiconductors. We further demonstrate asymmetric diodes based on multilayer graphene/MoS2/PtSe2 with a current rectification ratio exceeding 105 and an ideality factor of 1.2. Scanning photocurrent mapping shows that the photocurrent generation mechanism in the heterostructure switches from photovoltaic effect to photogating effect at varying drain biases, indicating both energy conversion and optical sensing are realized in a single device. In the photovoltaic mode, the photodetector is self-powered with a response time smaller than 100 µs under the illumination of a 405 nm laser. In the photogating mode, the photodetector exhibits a high responsivity up to 460 A/W originating from a high photogain. Finally, the photodetector is employed for single-pixel imaging, demonstrating its high-contrast photodetection ability. This work provides insight into the development of high-performance self-powered photodetectors based on 2D Schottky junctions.

12.
JAMA Oncol ; 10(7): 932-940, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38869865

RESUMEN

Importance: Uninterrupted targeted therapy until disease progression or intolerable toxic effects is currently the routine therapy for advanced non-small cell lung cancer (NSCLC) involving driver gene variations. However, drug resistance is inevitable. Objective: To assess the clinical feasibility of adaptive de-escalation tyrosine kinase inhibitor (TKI) treatment guided by circulating tumor DNA (ctDNA) for achieving complete remission after local consolidative therapy (LCT) in patients with advanced NSCLC. Design, Setting, and Participants: This prospective nonrandomized controlled trial was conducted at a single center from June 3, 2020, to July 19, 2022, and included 60 patients with advanced NSCLC with driver variations without radiologically detectable disease after TKI and LCT. The median (range) follow-up time was 19.2 (3.8-29.7) months. Data analysis was conducted from December 15, 2022, to May 10, 2023. Intervention: Cessation of TKI treatment and follow-up every 3 months. Treatment was restarted in patients with progressive disease (defined by the Response Evaluation Criteria in Solid Tumors 1.1 criteria), detectable ctDNA, or elevated carcinoembryonic antigen (CEA) levels, whichever manifested first, and treatment ceased if all indicators were negative during follow-up surveillance. Main Outcomes and Measures: Progression-free survival (PFS). Secondary end points were objective response rate, time to next treatment, and overall survival. Results: Among the total study sample of 60 participants (median [range] age, 55 [21-75] years; 33 [55%] were female), the median PFS was 18.4 (95% CI, 12.6-24.2) months and the median (range) total treatment break duration was 9.1 (1.5-28.1) months. Fourteen patients (group A) remained in TKI cessation with a median (range) treatment break duration of 20.3 (6.8-28.1) months; 31 patients (group B) received retreatment owing to detectable ctDNA and/or CEA and had a median PFS of 20.2 (95% CI, 12.9-27.4) months with a median (range) total treatment break duration of 8.8 (1.5-20.6) months; and 15 patients (group C) who underwent retreatment with TKIs due to progressive disease had a median PFS of 5.5 (95% CI, 1.5-7.2) months. For all participants, the TKI retreatment response rate was 96%, the median time to next treatment was 29.3 (95% CI, 25.3-35.2) months, and the data for overall survival were immature. Conclusions and Relevance: The findings of this nonrandomized controlled trial suggest that this adaptive de-escalation TKI strategy for patients with NSCLC is feasible in those with no lesions after LCT and a negative ctDNA test result. This might provide a de-escalation treatment strategy guided by ctDNA for the subset of patients with advanced NSCLC. Trial Registration: ClinicalTrials.gov Identifier: NCT03046316.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , ADN Tumoral Circulante , Neoplasias Pulmonares , Inhibidores de Proteínas Quinasas , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Masculino , ADN Tumoral Circulante/sangre , ADN Tumoral Circulante/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Persona de Mediana Edad , Anciano , Adulto , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/administración & dosificación , Estudios Prospectivos , Terapia Molecular Dirigida/métodos
13.
Heliyon ; 10(11): e32041, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38882297

RESUMEN

Objectives: To evaluate the outcomes of left-sided infective endocarditis that can be operated on and cannot be operated on, and to focus on modifiable risk factors for immediate and long-term mortality. Methods: This study retrospectively investigated patients with left-sided infective endocarditis who occurred in our medical center between January 2006 and November 2022. Results: 48 in-hospital deaths occurred (5.8 %, 48/832). We identified time from symptoms to admission and symptomatic neurological complications to be risk factors for multiple organ failure upon admission. Time from symptoms to admission and vegetation size in group of isolated medical treatment were significantly shorter than those in the group of heart operation. We also found that preoperative neurological complications, annulus destruction, levels of serum creatinine at 24 and 48 h post heart operation, and perivalvular leakage are risk factors for in-hospital mortality post heart operation. With 148 µmol/L as a cutoff level, the diagnostic sensitivity and specificity of serum creatinine level 48 h post surgery for in-hospital mortality post cardiac surgery are 100 % and 81.6 %, respectively. We found that vegetation size, ICU stay, postoperative serum creatinine at 48 h, left ventricular end diastolic size postoperative, and red blood cell transfusion were associated with all-time mortality. Conclusions: Early diagnosis and treatment, improvement of surgical techniques, good protection for heart, kidney and blood and close follow-up are advocated to conduce to better immediate and long-term outcomes of the operable and inoperable with left-sided infective endocarditis.

14.
Chem Biodivers ; 21(7): e202400900, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38713316

RESUMEN

A new compound xylarkarynone A (1), a first reported natural product compound xylarkarynone B (2) and eight known compounds (3-10) were isolated from Xylaria sp. HHY-2. Their structures were elucidated by spectroscopic methods, DP4+ probability analyses and electronic circular dichroism (ECD) calculations. The bioactivities of isolated compounds were assayed. Compound 1 exhibited obvious activity against A549 cells with an IC50 value of 6.12±0.28 µM. Additionally, compound 1 showed moderate antifungal activities against Plectosphaerella cucumerina and Aspergillus niger with minimum inhibitory concentrations (MICs) of both 16 µg/mL, which was at the same grade with positive control nystatin. Most compounds exhibited varying degrees of inhibitory activity against P. cucumerina, indicating that Xylaria sp. has potential as inhibitors against P. cucumerina.


Asunto(s)
Antifúngicos , Aspergillus niger , Pruebas de Sensibilidad Microbiana , Sesquiterpenos , Xylariales , Humanos , Xylariales/química , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Aspergillus niger/efectos de los fármacos , Células A549 , Ensayos de Selección de Medicamentos Antitumorales , Ascomicetos/química , Estructura Molecular , Conformación Molecular , Relación Estructura-Actividad , Relación Dosis-Respuesta a Droga
15.
Insect Sci ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769889

RESUMEN

Disruption of the circadian clock can affect starvation resistance, but the molecular mechanism is still unclear. Here, we found that starvation resistance was significantly reduced in the core gene BmPer deficient mutant silkworms (Per-/-), but the mutant's starvation resistance increased with larval age. Under natural physiological conditions, the weight of mutant 5th instar larvae was significantly increased compared to wild type, and the accumulation ability of triglycerides and glycogen in the fat bodies was upregulated. However, under starvation conditions, the weight consumption of mutant larvae was increased and cholesterol utilization was intensified. Transcriptome analysis showed that beta-oxidation was significantly upregulated under starvation conditions, fatty acid synthesis was inhibited, and the expression levels of genes related to mitochondrial function were significantly changed. Further investigations revealed that the redox balance, which is closely related to mitochondrial metabolism, was altered in the fat bodies, the antioxidant level was increased, and the pentose phosphate pathway, the source of reducing power in cells, was activated. Our findings suggest that one of the reasons for the increased energy burden observed in mutants is the need to maintain a more robust redox balance in metabolic tissues. This necessitates the diversion of more glucose into the pentose phosphate pathway to ensure an adequate supply of reducing power.

16.
Opt Express ; 32(7): 11801-11817, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571019

RESUMEN

A full-quantum approach is used to study the quantum nonlinear properties of a compound Michelson-Sagnac interferometer optomechanical system. By deriving the effective Hamiltonian, we find that the reduced system exhibits a Kerr nonlinear term with a complex coefficient, entirely induced by the dissipative and dispersive couplings. Unexpectedly, the nonlinearities resulting from the dissipative coupling possess non-Hermitian Hamiltonian-like properties preserving the quantum nature of the dispersive coupling beyond the traditional system dissipation. This protective mechanism allows the system to exhibit strong quantum nonlinear effects when the detuning (the compound cavity detuning Δc and the auxiliary cavity detuning Δe) and the tunneling coupling strength (J) of two cavities satisfy the relation J2 = ΔcΔe. Moreover, the additive effects of dispersive and dissipative couplings can produce strong anti-bunching effects, which exist in both strong and weak coupling conditions. Our work may provide a new way to study and produce strong quantum nonlinear effects in dissipatively coupled optomechanical systems.

17.
Oncoimmunology ; 13(1): 2340154, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38601319

RESUMEN

Metabolism reprogramming within the tumor microenvironment (TME) can have a profound impact on immune cells. Identifying the association between metabolic phenotypes and immune cells in lung adenocarcinoma (LUAD) may reveal mechanisms of resistance to immune checkpoint inhibitors (ICIs). Metabolic phenotypes were classified by expression of metabolic genes. Somatic mutations and transcriptomic features were compared across the different metabolic phenotypes. The metabolic phenotype of LUAD is predominantly determined by reductase-oxidative activity and is divided into two categories: redoxhigh LUAD and redoxlow LUAD. Genetically, redoxhigh LUAD is mainly driven by mutations in KEAP1, STK11, NRF2, or SMARCA4. These mutations are more prevalent in redoxhigh LUAD (72.5%) compared to redoxlow LUAD (17.4%), whereas EGFR mutations are more common in redoxlow LUAD (19.0% vs. 0.7%). Single-cell RNA profiling of pre-treatment and post-treatment samples from patients receiving neoadjuvant chemoimmunotherapy revealed that tissue-resident memory CD8+ T cells are responders to ICIs. However, these cells are significantly reduced in redoxhigh LUAD. The redoxhigh phenotype is primarily attributed to tumor cells and is positively associated with mTORC1 signaling. LUAD with the redoxhigh phenotype demonstrates a lower response rate (39.1% vs. 70.8%, p = 0.001), shorter progression-free survival (3.3 vs. 14.6 months, p = 0.004), and overall survival (12.1 vs. 31.2 months, p = 0.022) when treated with ICIs. The redoxhigh phenotype in LUAD is predominantly driven by mutations in KEAP1, STK11, NRF2, and SMARCA4. This phenotype diminishes the number of tissue-resident memory CD8+ T cells and attenuates the efficacy of ICIs.


Asunto(s)
Quinasas de la Proteína-Quinasa Activada por el AMP , Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Factor 2 Relacionado con NF-E2/genética , Proteína 1 Asociada A ECH Tipo Kelch/genética , Oxidación-Reducción , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Inmunoterapia , Mutación , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Linfocitos T , Linfocitos T CD8-positivos , Microambiente Tumoral/genética , ADN Helicasas , Proteínas Nucleares , Factores de Transcripción
18.
Proc Natl Acad Sci U S A ; 121(14): e2308132121, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38551841

RESUMEN

Tumor necrosis factor (TNF) receptor 1 (TNFR1) plays a pivotal role in mediating TNF induced downstream signaling and regulating inflammatory response. Recent studies have suggested that TNFR1 activation involves conformational rearrangements of preligand assembled receptor dimers and targeting receptor conformational dynamics is a viable strategy to modulate TNFR1 signaling. Here, we used a combination of biophysical, biochemical, and cellular assays, as well as molecular dynamics simulation to show that an anti-inflammatory peptide (FKCRRWQWRMKK), which we termed FKC, inhibits TNFR1 activation allosterically by altering the conformational states of the receptor dimer without blocking receptor-ligand interaction or disrupting receptor dimerization. We also demonstrated the efficacy of FKC by showing that the peptide inhibits TNFR1 signaling in HEK293 cells and attenuates inflammation in mice with intraperitoneal TNF injection. Mechanistically, we found that FKC binds to TNFR1 cysteine-rich domains (CRD2/3) and perturbs the conformational dynamics required for receptor activation. Importantly, FKC increases the frequency in the opening of both CRD2/3 and CRD4 in the receptor dimer, as well as induces a conformational opening in the cytosolic regions of the receptor. This results in an inhibitory conformational state that impedes the recruitment of downstream signaling molecules. Together, these data provide evidence on the feasibility of targeting TNFR1 conformationally active region and open new avenues for receptor-specific inhibition of TNFR1 signaling.


Asunto(s)
Receptores Tipo I de Factores de Necrosis Tumoral , Transducción de Señal , Ratones , Humanos , Animales , Ligandos , Células HEK293 , Factor de Necrosis Tumoral alfa/metabolismo , Péptidos/farmacología
19.
mSphere ; 9(4): e0081623, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38470044

RESUMEN

Anaerostipes hadrus (A. hadrus) is a dominant species in the human gut microbiota and considered a beneficial bacterium for producing probiotic butyrate. However, recent studies have suggested that A. hadrus may negatively affect the host through synthesizing fatty acid and metabolizing the anticancer drug 5-fluorouracil, indicating that the impact of A. hadrus is complex and unclear. Therefore, comprehensive genomic studies on A. hadrus need to be performed. We integrated 527 high-quality public A. hadrus genomes and five distinct metagenomic cohorts. We analyzed these data using the approaches of comparative genomics, metagenomics, and protein structure prediction. We also performed validations with culture-based in vitro assays. We constructed the first large-scale pan-genome of A. hadrus (n = 527) and identified 5-fluorouracil metabolism genes as ubiquitous in A. hadrus genomes as butyrate-producing genes. Metagenomic analysis revealed the wide and stable distribution of A. hadrus in healthy individuals, patients with inflammatory bowel disease, and patients with colorectal cancer, with healthy individuals carrying more A. hadrus. The predicted high-quality protein structure indicated that A. hadrus might metabolize 5-fluorouracil by producing bacterial dihydropyrimidine dehydrogenase (encoded by the preTA operon). Through in vitro assays, we validated the short-chain fatty acid production and 5-fluorouracil metabolism abilities of A. hadrus. We observed for the first time that A. hadrus can convert 5-fluorouracil to α-fluoro-ß-ureidopropionic acid, which may result from the combined action of the preTA operon and adjacent hydA (encoding bacterial dihydropyrimidinase). Our results offer novel understandings of A. hadrus, exceptionally functional features, and potential applications. IMPORTANCE: This work provides new insights into the evolutionary relationships, functional characteristics, prevalence, and potential applications of Anaerostipes hadrus.

20.
Front Nutr ; 11: 1218912, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38481974

RESUMEN

Objectives: The associations of posteriori dietary patterns with the risk of hyperuricemia (HUA) are contradictory. Several fair-quality observational studies with inconsistent results have been published following a prior review. Herein, we carried out an updated systematic review and meta-analysis to quantitatively analyze the aforementioned relationships. Methods: Our analysis protocol has been registered with PROSPEPO (Number: CRD42022376745). English publications were searched in Embase, PubMed, and Web of Science from inception to January 1, 2024. Summary odds ratio (OR) and 95% confidence intervals (CIs) were calculated by a random-effects model. We also conducted subgroup, sensitivity, and meta-regression analyses and publication bias assessments. Results: Thirteen studies with a total of 163,192 participants were included in the current meta-analysis. Our finding revealed that the plant-based pattern was linked with a 17% decreased risk of HUA (OR = 0.83, 95%CI = 0.72-0.94, I2 = 72.9%, n = 10). There was no evidence of publication bias in the present analysis. The results of subgroup analyses were generally consistent with the main findings. In meta-regression analyses, no evidence of heterogeneity was detected in the subgroups. Furthermore, our analyses indicated that the animal-based food pattern (OR = 1.36, 95%CI = 1.25-1.47, I2 = 26.7%, n = 11) and sweet food pattern (OR = 1.24, 95%CI = 1.06-1.46, I2 = 0, n = 2) was related to an increased risk of HUA. Conclusion: The plant-based pattern is inversely correlated with HUA risk, whereas animal-based food patterns and sweet food patterns are positively correlated with HUA risk.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA