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1.
Cell ; 154(4): 748-62, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23910378

RESUMEN

Binding of dsDNA by cyclic GMP-AMP (cGAMP) synthase (cGAS) triggers formation of the metazoan second messenger c[G(2',5')pA(3',5')p], which binds the signaling protein STING with subsequent activation of the interferon (IFN) pathway. We show that human hSTING(H232) adopts a "closed" conformation upon binding c[G(2',5')pA(3',5')p] and its linkage isomer c[G(2',5')pA(2',5')p], as does mouse mSting(R231) on binding c[G(2',5')pA(3',5')p], c[G(3',5')pA(3',5')p] and the antiviral agent DMXAA, leading to similar "closed" conformations. Comparing hSTING to mSting, 2',5'-linkage-containing cGAMP isomers were more specific triggers of the IFN pathway compared to the all-3',5'-linkage isomer. Guided by structural information, we identified a unique point mutation (S162A) placed within the cyclic-dinucleotide-binding site of hSTING that rendered it sensitive to the otherwise mouse-specific drug DMXAA, a conclusion validated by binding studies. Our structural and functional analysis highlights the unexpected versatility of STING in the recognition of natural and synthetic ligands within a small-molecule pocket created by the dimerization of STING.


Asunto(s)
Antivirales/farmacología , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Nucleótidos Cíclicos/metabolismo , Xantonas/farmacología , Animales , Cristalografía por Rayos X , GMP Cíclico/metabolismo , Humanos , Factor 3 Regulador del Interferón/metabolismo , Interferón Tipo I/metabolismo , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/genética , Ratones , Modelos Moleculares , Mutagénesis , Conformación Proteica , Transducción de Señal , Relación Estructura-Actividad
2.
Crit Rev Immunol ; 44(2): 77-87, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38305338

RESUMEN

Rhizoma Dioscoreae Nipponicae (RDN) is a traditional Chinese medicine that widely applied in the treatment of human diseases. This study aims to explore the therapeutic potential of RDN in asthma and the underlying mechanisms. A mouse model of asthma was established by the stimulation of ovalbumin (OVA). HE staining was performed to detect the pathological injuries of tracheal tissues. The protein expression of collagen I, FN1, α-SMA (airway remodeling markers), and p-p38 (a marker of the p38 MAPK pathway) were detected by Western blot. Eosinophils were then isolated from the model mice. Cell viability and ROS level were measured by CCK-8 and Flow cytometry, respectively. The mRNA expression of GPX4 and ACSL4 (ferroptosis markers) in eosinophils were measured by qRT-PCR. RDN significantly reduced the numbers of total cells and eosnophils in bronchoalveolar lavage fluid (BALF), inhibited inflammatory cell infiltration, and down-regulated remodeling markers (Collagen I, FN1, and α-SMA) in OVA-induced mice. The p38 MAPK pathway was blocked by the intervention of RDN in the model mice, and its blocking weakens the poor manifestations of OVA-induced asthma. In addition, RDN induced the ferroptosis of eosnophils both in vitro and in vivo. Blocking of the p38 MAPK pathway also enhanced the ferroptosis of eosnophils in vitro, evidenced by the decreased cell viability and GPX4 expression, and increased ROS level and ACSL4 expression. RDN induced the ferroptosis of eosinophils through inhibiting the p38 MAPK pathway, contributing to the remission of asthma.


Asunto(s)
Asma , Ferroptosis , Animales , Humanos , Ratones , Asma/metabolismo , Colágeno/metabolismo , Modelos Animales de Enfermedad , Eosinófilos/metabolismo , Pulmón/patología , Ovalbúmina/efectos adversos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal
3.
Anal Chem ; 96(11): 4359-4368, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38452345

RESUMEN

Microorganisms are important sources of bioactive natural products. However, the complexity of microbial metabolites and the low abundance of active compounds render the isolation and purification process laborious and inefficient. During our search for active substances capable of inhibiting the newly discovered highly lethal Vibrio strain vp-HL, we found that the fermentation broth of multiple Bacillus strains exhibited antibacterial activity. However, the substances responsible for the activity remained unclear. Metabolomics, molecular networking (MN), and the Structural similarity Network Annotation Platform for Mass Spectrometry (SNAP-MS) were employed in conjunction with bioactivity screening to predict the antibacterial compounds from Bacillus strains. The analysis of fractions, and their isolation, NMR-based annotation, and bioactivity evaluation of an amicoumacin compound partially confirmed the prediction from these statistical analyses. This work presents the potential of marine Bacillus in producing active substances against Vibrio species. Additionally, it highlighted the significance and feasibility of metabolomics and MN in the dereplication of compounds and the determination of isolation targets.


Asunto(s)
Bacillus , Vibrio , Bacillus/metabolismo , Metabolómica/métodos , Antibacterianos/química , Espectrometría de Masas
4.
Pediatr Res ; 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38582946

RESUMEN

BACKGROUND: Growth hormone deficiency(GHD) and idiopathic short stature(ISS) are the primary causes of short stature in children. Animal experiments have revealed a link between growth hormone(GH), gut microbiota and metabolism, however, limited information is available from human trials. METHODS: Fecal samples collected from GHD (n = 36), ISS (n = 32) and healthy control (HC) children(n = 16) were subjected to microbiome (16 S rRNA gene sequencing) and metabolome (nuclear magnetic resonance,NMR) analyses. RESULTS: GHD, ISS and HC exhibit distinct differences in beta diversity of gut microbiota.In addition, short stature (GHD and ISS) exhibit higher relative abundance of Prevotellaceae_NK3B31_group at genus level compared to HC, whereas Rodentibacter, Rothia, and Pelomonas showed lower abundance. Additionally,Fusobacterium_mortiferum was identified as the characteristic species of GHD. Moreover, glucose metabolism, pyruvate metabolism and pyrimidine metabolism might play significant roles for distinguishing between GHD and normal GH groups (ISS and HC). Furthermore, a disease prediction model based on differential bacteria and metabolites between GHD and ISS exhibited high diagnostic value. CONCLUSION: These findings highlight the characteristics of different GH levels on the gut microbiota and metabolism in children, providing novel perspectives for early diagnosis and prognostic treatment of short stature with abnormal GH levels. IMPACT: The key message of our study is to identify human-relevant gut microbiota and host metabolic patterns that are interfered with growth hormone levels, and to develop biomarker models to identify short stature associated with growth hormone deficiency. We used idiopathic short stature as a control group for growth hormone deficiency, complementing the absence of height as a factor in the existing literature. Our study ultimately hopes to shed new light on the diagnosis and treatment of short stature children associated with growth hormone deficiency.

5.
Biomacromolecules ; 25(6): 3217-3248, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38237033

RESUMEN

Hydrogel, as a unique scaffold material, features a three-dimensional network system that provides conducive conditions for the growth of cells and tissues in bone tissue engineering (BTE). In recent years, it has been discovered that metal ion-containing hybridized hydrogels, synthesized with metal particles as the foundation, exhibit excellent physicochemical properties, osteoinductivity, and osteogenic potential. They offer a wide range of research prospects in the field of BTE. This review provides an overview of the current state and recent advancements in research concerning metal ion-containing hydrogels in the field of BTE. Within materials science, it covers topics such as the binding mechanisms of metal ions within hydrogel networks, the types and fabrication methods of various metal ion-containing hydrogels, and the influence of metal ions on the properties of hydrogels. In the context of BTE, the review delves into the osteogenic mechanisms of various metal ions, the applications of metal ion-containing hydrogels in BTE, and relevant experimental studies in vitro and in vivo. Furthermore, future improvements in bone repair can be anticipated through advancements in bone bionics, exploring interactions between metal ions and the development of a wider range of metal ions and hydrogel types.


Asunto(s)
Huesos , Hidrogeles , Metales , Ingeniería de Tejidos , Ingeniería de Tejidos/métodos , Hidrogeles/química , Hidrogeles/síntesis química , Hidrogeles/farmacología , Humanos , Huesos/efectos de los fármacos , Metales/química , Animales , Osteogénesis/efectos de los fármacos , Andamios del Tejido/química , Iones/química , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/farmacología
6.
J Nat Prod ; 87(4): 1203-1208, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38359398

RESUMEN

Chemical investigation of Irpex sp. NBUF088, associated with an Ircinia sp. sponge located at an 84 m deep mesophotic zone, led to the discovery of two new heptaketides, named irpetones A (1) and B (2). Their structures were identified by analysis of spectroscopic data and quantum-chemical calculations. Compound 1 exhibited inhibition against the receptor activator of NF-κB ligand-induced osteoclastogenesis in bone marrow monocytes with an IC50 of 6.3 ± 0.2 µM, causing no notable cytotoxicity. It was also determined that 1 inhibited the phosphorylation of ERK1/2-JNK1/2-p38 MAPKs and the nuclear translocation of NF-κB, consequently suppressing the activation of MAPK and NF-κB signaling pathways induced by the NF-κB ligand.


Asunto(s)
Osteoclastos , Poríferos , Animales , Poríferos/microbiología , Estructura Molecular , Osteoclastos/efectos de los fármacos , FN-kappa B/metabolismo , Ratones , Osteogénesis/efectos de los fármacos
7.
Mar Drugs ; 22(4)2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38667803

RESUMEN

Three novel meroterpenoids, taladrimanins B-D (1-3), were isolated from the marine-derived fungus Talaromyces sp. M27416, alongside three biogenetically related compounds (4-6). We delineated taladrimanin B's (1) structure using HRESIMS and NMR, confirmed its configuration via quantum chemical NMR analysis and DP4+ methodology, and verified it through X-ray crystallography. ECD calculations determined the absolute configuration of compound 1, while comparative NMR and ECD analyses elucidated the absolute configurations of 2 and 3. These compounds are drimane-type meroterpenoids with a C10 polyketide unit (8R-configuration). We proposed a biosynthetic pathway and noted that compound 1 showed cytotoxic activity against MKN-45 and 5637 cell lines and selective antibacterial effects against Staphylococcus aureus CICC 10384.


Asunto(s)
Antibacterianos , Staphylococcus aureus , Talaromyces , Terpenos , Talaromyces/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Humanos , Línea Celular Tumoral , Staphylococcus aureus/efectos de los fármacos , Terpenos/farmacología , Terpenos/química , Terpenos/aislamiento & purificación , Cristalografía por Rayos X , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Organismos Acuáticos , Estructura Molecular , Espectroscopía de Resonancia Magnética
8.
Mar Drugs ; 22(6)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38921585

RESUMEN

Talaromyces, a filamentous fungus widely distributed across terrestrial and marine environments, can produce a diverse array of natural products, including alkaloids, polyketones, and polyketide-terpenoids. Among these, chrodrimanins represented a typical class of natural products. In this study, we isolated three previously undescribed pentaketide-sesquiterpenes, 8,9-epi-chrodrimanins (1-3), along with eight known compounds (4-11). The structures of compounds 1-3 were elucidated using nuclear magnetic resonance (NMR) and mass spectrometry (MS), while their absolute configurations were determined through X-ray crystallography and electronic circular dichroism (ECD) computations. The biosynthetic pathways of compounds 1-3 initiate with 6-hydroxymellein and involve multiple stages of isoprenylation, cyclization, oxidation, and acetylation. We selected four strains of gastrointestinal cancer cells for activity evaluation. We found that compound 3 selectively inhibited MKN-45, whereas compounds 1 and 2 exhibited no significant inhibitory activity against the four cell lines. These findings suggested that 8,9-epi-chrodrimanins could serve as scaffold compounds for further structural modifications, potentially leading to the development of targeted therapies for gastric cancer.


Asunto(s)
Antineoplásicos , Talaromyces , Talaromyces/química , Humanos , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Cristalografía por Rayos X , Productos Biológicos/farmacología , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Organismos Acuáticos , Espectroscopía de Resonancia Magnética , Policétidos/farmacología , Policétidos/química , Policétidos/aislamiento & purificación , Estructura Molecular
9.
Alzheimers Dement ; 20(4): 2516-2525, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38329281

RESUMEN

INTRODUCTION: The objective of this study is to investigate the incremental value of amyloid positron emission tomography (Aß-PET) in a tertiary memory clinic setting in China. METHODS: A total of 1073 patients were offered Aß-PET using 18F-florbetapir. The neurologists determined a suspected etiology (Alzheimer's disease [AD] or non-AD) with a percentage estimate of their confidence and medication prescription both before and after receiving the Aß-PET results. RESULTS: After disclosure of the Aß-PET results, etiological diagnoses changed in 19.3% of patients, and diagnostic confidence increased from 69.3% to 85.6%. Amyloid PET results led to a change of treatment plan in 36.5% of patients. Compared to the late-onset group, the early-onset group had a more frequent change in diagnoses and a higher increase in diagnostic confidence. DISCUSSION: Aß-PET has significant impacts on the changes of diagnoses and management in Chinese population. Early-onset cases are more likely to benefit from Aß-PET than late-onset cases. HIGHLIGHTS: Amyloid PET contributes to diagnostic changes and its confidence in Chinese patients. Amyloid PET leads to a change of treatment plans in Chinese patients. Early-onset cases are more likely to benefit from amyloid PET than late-onset cases.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Amiloide , Enfermedad de Alzheimer/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Proteínas Amiloidogénicas , Compuestos de Anilina , China , Péptidos beta-Amiloides , Disfunción Cognitiva/diagnóstico
10.
J Environ Manage ; 352: 120049, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38232592

RESUMEN

Gallium arsenide (GaAs) is the most widely used second-generation semiconductor material. However, a large amount of GaAs scrap is generated at various stages of the GaAs wafer production process. Volatile GaAs clusters are inevitably generated during the process of GaAs vacuum thermal decomposition, resulting in lower purity of the recovered arsenic and the loss of gallium. In this study, thermodynamic analysis and dynamics simulation were combined to discuss the possibility of separating GaAs clusters and arsenic from a microscopic perspective. A vacuum thermal decomposition-directional condensation recovery process for GaAs scrap was proposed. By properly adjusting the separation parameters such as heating temperature, holding time and raw material size, high purity of gallium (99.99%) and arsenic (99.5%) were directly recovered under a system pressure of 1 Pa, heating temperature of 1323 K, holding time of 3 h, and GaAs scrap size of 2.5 cm. GaAs clusters were also recovered in powder form. The problem of difficult separation of GaAs clusters from arsenic was effectively solved by this method, and the purity of recovered arsenic was greatly improved. No additives are required and no waste liquid or gas emission in the whole process. The complexity of subsequent arsenic purification operations and the threat of arsenic containing waste to the environment were reduced as well.


Asunto(s)
Arsénico , Arsenicales , Galio
11.
BMC Bioinformatics ; 24(1): 226, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37264324

RESUMEN

BACKGROUND: Comutation plot is a widely used visualization method to deliver a global view of the mutation landscape of large-scale genomic studies. Current tools for creating comutation plot are either offline packages that require coding or online web servers with varied features. When a package is used, it often requires repetitive runs of code to adjust a single feature that might only be a few clicks in a web app. But web apps mostly have limited capacity for customization and cannot handle very large genomic files. RESULTS: To improve on existing tools, we identified features that are most frequently adjusted in creating a plot and incorporate them in Comut-viz that interactively filters and visualizes mutation data as downloadable plots. It includes colored labels for numeric metadata, a preloaded palette for changing colors and two input boxes for adjusting width and height. It accepts standard mutation annotation format (MAF) files as input and can handle large MAF files with more than 200 k rows. As a front-end only app, Comut-viz guarantees privacy of user data and no latency in the analysis. CONCLUSIONS: Comut-viz is a highly responsive and extensible web app to make comutation plots. It provides customization for frequently adjusted features and accepts large genomic files as input. It is suitable for genomic studies with more than a thousand samples.


Asunto(s)
Genoma , Genómica , Genómica/métodos , Mutación , Programas Informáticos
12.
J Am Chem Soc ; 145(44): 24012-24020, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37903430

RESUMEN

Understanding charge transport among metal particles with sizes of approximately 1 nm poses a great challenge due to the ultrasmall nanosize, yet it holds great significance in the development of innovative materials as substitutes for traditional semiconductors, which are insulative and unstable in less than ∼10 nm thickness. Herein, atomically precise gold nanoclusters with well-defined compositions and structures were investigated to establish a mathematical relation between conductivity and interparticle distance. This was accomplished using high-pressure in situ resistance characterizations, synchrotron X-ray diffraction (XRD), and the Murnaghan equation of state. Based on this precise correlation, it was predicted that the conductivity of Au25(SNap)18 (SNap: 1-naphthalenethiolate) solid is comparable to that of bulk silver when the interparticle distance is reduced to approximately 3.6 Å. Furthermore, the study revealed the coexisting, competing tunneling, and incoherent hopping charge transport mechanisms, which differed from those previously reported. The introduction of conjugation-structured ligands, tuning of the structures of metal nanoclusters, and use of high-pressure techniques contributed to enhanced conductivity, and thus, the charge carrier types were determined using Hall measurements. Overall, this study provides valuable insight into the charge transport in gold nanocluster solids and represents an important advancement in metal nanocluster semiconductor research.

13.
Pharmacol Res ; 189: 106703, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36804016

RESUMEN

Gastric cancer remains one of the most common deadly diseases and lacks effective targeted therapies. In the present study, we confirmed that the signal transducer and activator of transcription 3 (STAT3) is highly expressed and associated with a poor prognosis in gastric cancer. We further identified a novel natural product inhibitor of STAT3, termed XYA-2, which interacts specifically with the SH2 domain of STAT3 (Kd= 3.29 µM) and inhibits IL-6-induced STAT3 phosphorylation at Tyr705 and nuclear translocation. XYA-2 inhibited the viability of seven human gastric cancer cell lines with 72-h IC50 values ranging from 0.5 to 0.7 µΜ. XYA-2 at 1 µΜ inhibited the colony formation and migration ability of MGC803 (72.6% and 67.6%, respectively) and MKN28 (78.5% and 96.6%, respectively) cells. In the in vivo studies, intraperitoneal administration of XYA-2 (10 mg/kg/day, 7 days/week) significantly suppressed 59.8% and 88.8% tumor growth in the MKN28-derived xenograft mouse model and MGC803-derived orthotopic mouse model, respectively. Similar results were obtained in a patient-derived xenograft (PDX) mouse model. Moreover, XYA-2 treatment extended the survival of mice bearing PDX tumors. The molecular mechanism studies based on transcriptomics and proteomics analyses indicated that XYA-2 might exert its anticancer activity by synergistically inhibiting the expression of MYC and SLC39A10, two downstream genes of STAT3 in vitro and in vivo. Together, these findings suggested that XYA-2 may be a potent STAT3 inhibitor for treating gastric cancer, and dual inhibition of MYC and SLC39A10 may be an effective therapeutic strategy for STAT3-activated cancer.


Asunto(s)
Neoplasias Gástricas , Humanos , Animales , Ratones , Neoplasias Gástricas/patología , Línea Celular Tumoral , Factor de Transcripción STAT3/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Fosforilación , Proliferación Celular , Apoptosis
14.
J Endovasc Ther ; : 15266028231158294, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36891634

RESUMEN

PURPOSE: This study aimed to develop and internally validate nomograms for predicting restenosis after endovascular treatment of lower extremity arterial diseases. MATERIALS AND METHODS: A total of 181 hospitalized patients with lower extremity arterial disease diagnosed for the first time between 2018 and 2019 were retrospectively collected. Patients were randomly divided into a primary cohort (n=127) and a validation cohort (n=54) at a ratio of 7:3. The least absolute shrinkage and selection operator (LASSO) regression was used to optimize the feature selection of the prediction model. Combined with the best characteristics of LASSO regression, the prediction model was established by multivariate Cox regression analysis. The predictive models' identification, calibration, and clinical practicability were evaluated by the C index, calibration curve, and decision curve. The prognosis of patients with different grades was compared by survival analysis. Internal validation of the model used data from the validation cohort. RESULTS: The predictive factors included in the nomogram were lesion site, use of antiplatelet drugs, application of drug coating technology, calibration, coronary heart disease, and international normalized ratio (INR). The prediction model demonstrated good calibration ability, and the C index was 0.762 (95% confidence interval: 0.691-0.823). The C index of the validation cohort was 0.864 (95% confidence interval: 0.801-0.927), which also showed good calibration ability. The decision curve shows that when the threshold probability of the prediction model is more significant than 2.5%, the patients benefit significantly from our prediction model, and the maximum net benefit rate is 30.9%. Patients were graded according to the nomogram. Survival analysis found that there was a significant difference in the postoperative primary patency rate between patients of different classifications (log-rank p<0.001) in both the primary cohort and the validation cohort. CONCLUSION: We developed a nomogram to predict the risk of target vessel restenosis after endovascular treatment by considering information on lesion site, postoperative antiplatelet drugs, calcification, coronary heart disease, drug coating technology, and INR. CLINICAL IMPACT: Clinicians can grade patients after endovascular procedure according to the scores of the nomograms and apply intervention measures of different intensities for people at different risk levels. During the follow-up process, an individualized follow-up plan can be further formulated according to the risk classification. Identifying and analyzing risk factors is essential for making appropriate clinical decisions to prevent restenosis.

15.
Inorg Chem ; 62(32): 13148-13155, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37532705

RESUMEN

Herein, we have successfully synthesized two rubidium antimony (III) oxalates, namely, Rb2Sb(C2O4)2.5(H2O)3 and RbSb2(C2O4)F5, utilizing a low-temperature hydrothermal method. These two compounds share a similar chemical composition, consisting of Sb3+ cations with active lone pair electrons, alkali metal Rb+ ions, and planar π-conjugated C2O42- anions. However, they exhibit different symmetries, Rb2Sb(C2O4)2.5(H2O)3 is centrosymmetric (CS), while RbSb2(C2O4)F5 is noncentrosymmetric (NCS), which should be caused by the presence of F- ions. Notably, the NCS compound, RbSb2(C2O4)F5, demonstrates a moderate second-harmonic generation (SHG) response, approximately 1.3 times that of KH2PO4 (KDP), and exhibits a large birefringence of 0.09 at 546 nm. These characteristics indicate that RbSb2(C2O4)F5 holds promising potential as a nonlinear optical material for ultraviolet (UV) applications. Detailed structural analysis and theoretical calculations confirm that the excellent optical properties arise from the synergistic effects between Sb3+ cations with SCALP and planar π-conjugated [C2O4]2- groups.

16.
Sensors (Basel) ; 23(13)2023 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-37447947

RESUMEN

One of the primary challenges in wireless blockchain networks is to ensure security and high throughput with constrained communication and energy resources. In this paper, with curve fitting on the collected blockchain performance dataset, we explore the impact of the data transmission rate configuration on the wireless blockchain system under different network topologies, and give the blockchain a utility function which balances the throughput, energy efficiency, and stale rate. For efficient blockchain network deployment, we propose a novel Graph Convolutional Neural Network (GCN)-based approach to quickly and accurately determine the optimal data transmission rate. The experimental results demonstrate that the average relative deviation between the blockchain utility obtained by our GCN-based method and the optimal utility is less than 0.21%.


Asunto(s)
Cadena de Bloques , Comunicación , Redes Neurales de la Computación
17.
J Neuroradiol ; 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37827488

RESUMEN

Recombinant human growth hormone (rhGH) is an approved method to improve the growth and ameliorate behavioral issues in children with short stature. However, the data concerning the effects of rhGH treatment on spontaneous brain activity remains unclear. This study included 35 children with short stature, categorized into two groups: the treated group (n = 14) and the untreated group (n = 21). All participants underwent resting-state functional magnetic resonance imaging (rs-fMRI) and neuropsychological assessments at baseline and at the end of a one-year follow-up. The rs-fMRI based amplitude of low frequency fluctuation (ALFF) analysis method was employed to assess spontaneous brain activity. Interaction effects between rhGH and time on ALFF were detected using a mixed-effects analysis. Additionally, Stepwise regression analysis was conducted to investigate the associations between ALFF values and significant clinical indicators. The treated group exhibited significant improvements in height, weight, insulin-like growth factor-1 (IGF-1) levels, insulin-like growth factor binding protein 3 (IGFBP-3) levels, and processing speed index (PSI) when reevaluated from baseline. The interaction effect of rhGH × time was evident in the right putamen (RPUT), where the ALFF value showed a significant increase following rhGH treatment, while also demonstrating a notable positive correlation with height. Moreover, The main effect of time was manifested as a significant decrease in the ALFF value of the left dorsolateral superior frontal gyrus (LSFG) within the untreated group during the follow-up period, concurrently displaying a positive correlation with age. In conclusion, rhGH treatment not only has a positive effect on the growth, cognition, and behavior of children with short stature, but also improves and normalizes spontaneous brain activity.

18.
Angew Chem Int Ed Engl ; 62(37): e202307626, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37439109

RESUMEN

Many terpenoids with isoprene unit(s) demonstrating critical biological activities have been isolated and characterized. In this study, we have developed a robust chem-stamp strategy for the construction of the key isoprene unit, which consists of two steps: one-carbon extension of aldehydes to the alkenyl boronates by the boron-Wittig reaction and the rhodium-catalyzed reaction of alkenyl boronates with 2,3-allenols to yield enals. This chem-stamp could readily be applied repeatedly and separately, enabling the modular concise synthesis of many natural and pharmaceutically active terpenoids, including retinal, ß-carotene, vitamin A, tretinoin, fenretinide, acitretin, ALRT1550, nigerapyrone C, peretinoin, and lycopene. Owing to the diversified availability of the starting materials, aldehydes and 2,3-allenols, creation of new non-natural terpenoids has been realized from four dimensions: the number of isoprene units, the side chain, and the two terminal groups.


Asunto(s)
Hemiterpenos , Terpenos , Butadienos , Aldehídos/química , Catálisis
19.
Anticancer Drugs ; 33(1): e103-e112, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34407043

RESUMEN

In our previous studies, we found that T24 lung metastatic cancer cells showed high invasion and metastasis abilities and cancer stem cell characteristics compared with T24 primary cancer cells. By screening for the expression of CXC chemokines in both cell lines, we found that CXCL5 is highly expressed in T24-L cells. The aim of this study is to shed light on the relationship of CXCL5 with epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs). RNAi technology was used to decrease CXCL5 expression in the T24-L cell line, and the EMT and CSCs of the shCXCL5 group and the control group were compared. The CXCR2 inhibitor SB225002 was used to inhibit the receptor of CXCL5 to determine the effect of the CXCL5/CXCR2 axis. The knockdown of CXCL5 expression in T24-L cells reduced their EMT and CSC characteristics. RT-PCR and Western blot analyses revealed the downregulation of N-cadherin, Vimentin and CD44. In addition, when CD44 expression was knocked down, the EMT ability of the cells was also inhibited. This phenomenon was most pronounced when both CXCL5 and CD44 were knocked down. CXCL5 and CD44 can affect the EMT and stem cell capacity of T24-L cells through some interaction.


Asunto(s)
Quimiocina CXCL5/genética , Receptores de Hialuranos/genética , Neoplasias Pulmonares/patología , Neoplasias de la Vejiga Urinaria/secundario , Cadherinas/fisiología , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/fisiología , Técnicas de Silenciamiento del Gen , Humanos , Vimentina/fisiología
20.
Org Biomol Chem ; 20(12): 2508-2517, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35266497

RESUMEN

Biseuphoids A (1) and B (2), two unprecedented ent-abietane-type diterpenoid dimers linked by monomeric blocks through C-17-C-12' and C-17-C-11', respectively, were isolated from Euphorbia fischeriana, along with their biogenesis related diterpenoid monomers, 17-hydroxyjolkinolide B (3), caudicifolin (4), and fischeriabietane C (5). Their structures were elucidated by extensive spectroscopy assisted by quantum chemical NMR and ECD calculations. The unusual dimeric skeletons are possibly derived from the adduct of diterpenoid monomers through Michael-like reactions. The novel dimers 1 and 2 exhibited inhibitory activities on soluble epoxide hydrolase (sEH) with IC50 values of 8.17 and 5.61 µM, respectively. Molecular dynamics studies illustrated that both 1 and 2 can occupy the catalytic pocket of sEH by forming stable hydrogen bonds with the key amino acid residues including Gln384, Asn378, Pro361, Ala365, Asn366, and Asn472.


Asunto(s)
Diterpenos , Euphorbia , Abietanos/química , Diterpenos/química , Epóxido Hidrolasas/metabolismo , Euphorbia/química , Estructura Molecular , Raíces de Plantas/química , Polímeros
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