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1.
PLoS Biol ; 22(3): e3002240, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38547242

RESUMO

MYCN activates canonical MYC targets involved in ribosome biogenesis, protein synthesis, and represses neuronal differentiation genes to drive oncogenesis in neuroblastoma (NB). How MYCN orchestrates global gene expression remains incompletely understood. Our study finds that MYCN binds promoters to up-regulate canonical MYC targets but binds to both enhancers and promoters to repress differentiation genes. MYCN binding also increases H3K4me3 and H3K27ac on canonical MYC target promoters and decreases H3K27ac on neuronal differentiation gene enhancers and promoters. WDR5 facilitates MYCN promoter binding to activate canonical MYC target genes, whereas MYCN recruits G9a to enhancers to repress neuronal differentiation genes. Targeting both MYCN's active and repressive transcriptional activities using both WDR5 and G9a inhibitors synergistically suppresses NB growth. We demonstrate that MYCN cooperates with WDR5 and G9a to orchestrate global gene transcription. The targeting of both these cofactors is a novel therapeutic strategy to indirectly target the oncogenic activity of MYCN.


Assuntos
Transformação Celular Neoplásica , Proteínas Nucleares , Humanos , Proteínas Nucleares/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Histona Metiltransferases/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Transcrição Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
2.
FASEB J ; 38(9): e23654, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38717442

RESUMO

Heart failure and cardiac remodeling are both characterized by mitochondrial dysfunction. Healthy mitochondria are required for adequate contractile activity and appropriate regulation of cell survival. In the mammalian heart, enhancement of the mitochondrial unfolded protein response (UPRmt) is cardioprotective under pressure overload conditions. We explored the UPRmt and the underlying regulatory mechanism in terms of hypertension-induced cardiac remodeling and the cardioprotective effect of metformin. Male spontaneously hypertensive rats and angiotensin II-treated neonatal rat cardiomyocytes were used to induce cardiac hypertrophy. The results showed that hypertension induced the formation of aberrant mitochondria, characterized by a reduced mtDNA/nDNA ratio and swelling, as well as lower levels of mitochondrial complexes I to V and inhibition of the expression of one protein subunit of each of complexes I to IV. Such changes eventually enlarged cardiomyocytes and increased cardiac fibrosis. Metformin treatment increased the mtDNA/nDNA ratio and regulated the UPRmt, as indicated by increased expression of activating transcription factor 5, Lon protease 1, and heat shock protein 60, and decreased expression of C/EBP homologous protein. Thus, metformin improved mitochondrial ultrastructure and function in spontaneously hypertensive rats. In vitro analyses revealed that metformin reduced the high levels of angiotensin II-induced mitochondrial reactive oxygen species in such animals and stimulated nuclear translocation of heat shock factor 1 (HSF1). Moreover, HSF1 small-interfering RNA reduced the metformin-mediated improvements in mitochondrial morphology and the UPRmt by suppressing hypertrophic signals and cardiomyocyte apoptosis. These results suggest that HSF1/UPRmt signaling contributes to the beneficial effects of metformin. Metformin-mediated targeting of mitochondrial protein homeostasis and modulation of HSF1 levels have potential therapeutic implications in terms of cardiac remodeling.


Assuntos
Fatores de Transcrição de Choque Térmico , Metformina , Miócitos Cardíacos , Resposta a Proteínas não Dobradas , Animais , Masculino , Ratos , Angiotensina II/farmacologia , Cardiomegalia/metabolismo , Cardiomegalia/tratamento farmacológico , Cardiomegalia/patologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Fatores de Transcrição de Choque Térmico/efeitos dos fármacos , Fatores de Transcrição de Choque Térmico/metabolismo , Hipertensão/metabolismo , Hipertensão/tratamento farmacológico , Metformina/farmacologia , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
3.
Chem Soc Rev ; 53(8): 3687-3713, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38411997

RESUMO

The cornerstones of the advancement of flexible optoelectronics are the design, preparation, and utilization of novel materials with favorable mechanical and advanced optoelectronic properties. Molecular crystalline materials have emerged as a class of underexplored yet promising materials due to the reduced grain boundaries and defects anticipated to provide enhanced photoelectric characteristics. An inherent drawback that has precluded wider implementation of molecular crystals thus far, however, has been their brittleness, which renders them incapable of ensuring mechanical compliance required for even simple elastic or plastic deformation of the device. It is perplexing that despite a plethora of reports that have in the meantime become available underpinning the flexibility of molecular crystals, the "discovery" of elastically or plastically deformable crystals remains limited to cases of serendipitous and laborious trial-and-error approaches, a situation that calls for a systematic and thorough assessment of these properties and their correlation with the structure. This review provides a comprehensive and concise overview of the current understanding of the origins of crystal flexibility, the working mechanisms of deformations such as plastic and elastic bending behaviors, and insights into the examples of flexible molecular crystals, specifically concerning photoelectronic changes that occur in deformed crystals. We hope this summary will provide a reference for future experimental and computational efforts with flexible molecular crystals aimed towards improving their mechanical behavior and optoelectronic properties, ultimately intending to advance the flexible optoelectronic technology.

4.
Mol Microbiol ; 120(5): 684-701, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37718557

RESUMO

Syphilis is a persistent sexually transmitted disease caused by infiltration of the elusive pathogen Treponema pallidum. Despite the prevalence of human polymorphonuclear neutrophils (hPMNs) within cutaneous lesions, which are characteristic of incipient syphilis, their role in T. pallidum infection remains unclear. Tp92 is the only T. pallidum helical outer membrane protein that exhibits structural features similar to those of outer membrane proteins in other gram-negative bacteria. However, the functional mechanism of this protein in immune cells remains unclear. Neutrophils are short-lived cells that undergo innate apoptosis in response to external stimuli that typically influence this process. In this study, we determined that Tp92 impedes the activation of procaspase-3 via the ERK MAPK, PI3K/Akt, and NF-κB signaling pathways, consequently suppressing caspase-3 activity within hPMNs, and thereby preventing hPMNs apoptosis. Furthermore, Tp92 could also modulate hPMNs apoptosis by enhancing the expression of the anti-apoptotic protein Mcl-1, stimulating IL-8 secretion, and preserving the mitochondrial membrane potential. These findings provide valuable insights into the molecular mechanisms underlying T. pallidum infection and suggest potential therapeutic targets for syphilis treatment.


Assuntos
NF-kappa B , Sífilis , Humanos , NF-kappa B/metabolismo , Treponema pallidum/genética , Treponema pallidum/metabolismo , Sífilis/metabolismo , Sífilis/microbiologia , Sífilis/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Membrana/metabolismo , Neutrófilos , Apoptose
5.
Anal Chem ; 96(28): 11463-11471, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38962829

RESUMO

In this work, we reported a cholesterol oxidase (Chox)-loaded platinum (Pt) nanozyme with the collaborative cascade nanoreactor for the construction of nanozyme-enzyme-linked immunosorbent assay (N-ELSA) models to realize high-throughput rapid evaluation of cancer markers. Considering the high specific surface area and manipulable surface sites, ZIF-8 was used as a substrate for natural enzyme and nanozyme loading. The constructed ZIF-8-Pt nanozyme platform exhibited efficient enzyme-like catalytic efficiency with a standard corrected activity of 60.59 U mg-1, which was 12 times higher than that of the ZIF-8 precursor, and highly efficient photothermal conversion efficiency (∼35.49%). In N-ELISA testing, developed multienzyme photothermal probes were immobilized in microplates based on antigen-antibody-specific reactions. Cholesterol was reacted in a cascade to reactive oxygen radicals, which attacked 3,3',5,5'-tetramethylbenzidine, causing it to oxidize and color change, thus exhibiting highly enhanced efficient photothermal properties. Systematic temperature evaluations were performed by a hand-held microelectromechanical system thermal imager under the excitation of an 808 nm surface light source to determine the cancer antigen 15-3 (CA15-3) profiles in the samples. Encouragingly, the temperature signal from the microwells increased with increasing CA15-3, with a linear range of 2 mU mL-1 to 100 U mL-1, considering it to be the sensor with the widest working range for visualization and portability available. This work provides new horizons for the development of efficient multienzyme portable colorimetric-photothermal platforms to help advance the community-based process of early cancer detection.


Assuntos
Colesterol Oxidase , Platina , Humanos , Platina/química , Colesterol Oxidase/química , Colesterol Oxidase/metabolismo , Ensaio de Imunoadsorção Enzimática , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/análise , Benzidinas/química , Colesterol/química , Colesterol/metabolismo , Colesterol/análise , Ensaios de Triagem em Larga Escala , Zeolitas/química
6.
Chemistry ; : e202400741, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38745544

RESUMO

To address key concerns on solid-state pyrene-based luminescent materials, we propose a novel and efficient mechanical bond strategy. This strategy results in a transformation from ACQ to AIE effect and a remarkable enhancement of pyrene emission in the solid state. Moreover, an unusual purification of emission is also achieved. Through computational calculation and experimental characterisation, finally determined by X-ray diffraction analysis, we prove that the excellent emissions result from mechanical bond induced refinement of molecular arrangements, including reduced π-π stacking, well-ordered packing and enhanced structural stability. This work demonstrates the potential of mechanical bond in the field of organic luminescent molecules, providing a new avenue for developing high-performance organic luminescent materials.

7.
J Org Chem ; 89(2): 986-993, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38196087

RESUMO

Two new energetic coordination compounds with 1D helical chain structures have been synthesized. First, the polyamine precursor 4,5-diamino-2-((4-amino-1,2,5-oxadiazole-3-yl)methyl)-2,4-dihydro-3H-1,2,4-triazole-3-imino chloride salt (TATAF-Cl) is obtained by incorporating 4-(chloromethyl)-1,2,5-oxadiazol-3-amine with 4H-1,2,4-triazole-3,4,5-triamine. Using a simple hydrothermal method, two energetic complexes, Ag(TATAF)(ClO4)2 (ECP-1) and Ag(TATAF)(NO3)2·H2O (ECP-2), with a helical 1D MOF structure of furazan and triazole were synthesized. Compounds ECP-1 and ECP-2 have relatively high nitrogen and oxygen content (N + O%: 52.04%, 61.04%), excellent crystal density (2.229 g cm-3, 2.116 g cm-3 at 298 K) and high heat of detonation (1.18 kcal g-1, 1.06 kcal g-1), good detonation performance (P: 35.34 GPa, 29.52 GPa; Dv: 8412 m s-1, 7794 m s-1), and moderate sensitivity (IS: 8 J, 13 J; FS: 72 N, 64 N). Structurally, the Ag+ of the two ECPs is coordinated with two energetic cations, two perchlorates, or one nitrate via tetragonal coordination to form a single helical structure that is interspersed up and down in two directions.

8.
Inorg Chem ; 63(19): 8958-8969, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38687123

RESUMO

Atomically precise Ag4Ni2 nanoclusters with 2,4-dimethylbenzenethiol as the ligands were synthesized and characterized as a cocatalyst of SiC for the selective hydrogenation of nitroarenes to arylamine in the presence of NaBH4. The obtained Ag4Ni2/SiC samples exhibited extraordinary catalytic activity, and a self-accelerated catalytic process was observed with the reduction of nitrophenol to aminophenol as the model reaction. Experimental comparison between the Ag4Ni2/SiC samples before and after the catalysis showed that the transformation of Ag4Ni2 clusters to polydisperse Ag particles as well as amorphous NiOx on the surface of SiC in the catalysis was the key to their high activity. AIMD calculations revealed that the transformation of Ag4Ni2 was driven by the presence of multiple hydrides on the cluster, which induced the detachment of the thiol ligand of the nanoclusters.

9.
BMC Pregnancy Childbirth ; 24(1): 268, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605288

RESUMO

BACKGROUND: Although acetaminophen is widely used in women during pregnancy, its safety has not been clearly stated. The study aimed to investigate the association between acetaminophen use and adverse pregnancy outcomes in pregnant women in China. METHODS: We conducted a retrospective cohort study by collecting data on pregnant women who delivered in the Beijing Obstetrics and Gynecology Hospital from January 2018 to September 2023. An acetaminophen use group and a control group were formed based on prenatal exposure to acetaminophen. The pregnancy outcomes that we focused on were stillbirth, miscarriage, preterm birth, APGAR score, birth weight, and congenital disabilities. Pregnant women exposed to acetaminophen were matched to unexposed in a 1:1 ratio with propensity score matching, using the greedy matching macro. SPSS software was used for statistical analysis. Multivariable logistics regression was used to assess the association between acetaminophen use during pregnancy and adverse pregnancy outcomes. RESULTS: A total of 41,440 pregnant women were included, of whom 501 were exposed to acetaminophen during pregnancy, and 40,939 were not exposed. After the propensity score matching, the acetaminophen use and control groups consisted of 501 pregnant women each. The primary analysis showed that acetaminophen exposure during pregnancy was associated with an increased risk of stillbirth (adjusted OR (aOR) = 2.29, 95% CI, 1.19-4.43), APGAR score < 7 at 1 min (aOR = 3.28, 95% CI, 1.73-6.21), APGAR score < 7 at 5 min (aOR = 3.54, 95% CI, 1.74-7.20), APGAR score < 7 at 10 min (aOR = 3.18, 95% CI, 1.58-6.41), and high birth weight (HBW) (aOR = 1.75, 95% CI, 1.05-2.92). Drug exposure during the first and second trimesters increased the odds of stillbirth, miscarriage, APGAR < 7, and the occurrence of at least one adverse pregnancy outcome. In addition, the frequency of drug use more than two times was associated with a higher risk of preterm birth and APGAR score < 7. CONCLUSIONS: Exposure to acetaminophen during pregnancy was significantly associated with the occurrence of adverse pregnancy outcomes, particularly exposure in the first and second trimesters and frequency of use more than twice. It is suggested that acetaminophen should be prescribed with caution in pregnant women.


Assuntos
Aborto Espontâneo , Complicações na Gravidez , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Gestantes , Natimorto/epidemiologia , Peso ao Nascer , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Acetaminofen/efeitos adversos , Estudos Retrospectivos , Aborto Espontâneo/induzido quimicamente , Aborto Espontâneo/epidemiologia , Pontuação de Propensão , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia
10.
BMC Geriatr ; 24(1): 550, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918727

RESUMO

BACKGROUND: Potentially inappropriate medications (PIMs) are common among older adults with cancer, but their association with overall survival (OS) among non-small cell lung cancer (NSCLC) patients remains unclear. This study aimed to investigate the association between the use of PIMs and OS in patients with NSCLC. METHODS: In this cohort study, we included patients ≥ 65 years with newly diagnosed NSCLC from January 2014 to December 2020. Potentially inappropriate medication (PIM) is defined by the Beers criteria of 2019 at baseline and within six months following the initiation of systemic therapy. Multivariable Cox regression model was built to assess the association between PIMs and overall survival (OS). RESULTS: We finally included 338 patients with a median follow-up for OS of 1777 days. The prevalence of patients receiving at least one PIM was 39.9% (135/338) and 61.2% (71/116) at baseline and after systemic therapy, respectively. The most important factor associated with PIM use was the number of prescribed medications (P < 0.001). Baseline PIM use and PIM after systemic therapy were significantly associated with inferior OS (476 days vs. 844 days, P = 0.044; and 633 days vs. 1600 days, P = 0.007; respectively). In multivariable analysis, both baseline PIM use and PIM after systemic therapy were independent predictors of poor prognosis (adjusted HR, 1.33; 95% CI, 1.01-1.75; P = 0.041; and adjusted HR, 1.86; 95% CI, 1.11-3.14; P = 0.020; respectively). CONCLUSIONS: PIMs are prevalent among older patients with NSCLC and are independent predictors of NSCLC prognosis. There is an urgent need for clinicians to conduct medication reconciliation and appropriate deprescribing for this population, especially for patients with multiple PIMs.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Lista de Medicamentos Potencialmente Inapropriados , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Masculino , Feminino , Idoso , Neoplasias Pulmonares/tratamento farmacológico , Prognóstico , Idoso de 80 Anos ou mais , Estudos de Coortes , Estudos Retrospectivos , Prescrição Inadequada/tendências
11.
Artigo em Inglês | MEDLINE | ID: mdl-38376088

RESUMO

Treponema pallidum is the causative factor of syphilis, a sexually transmitted disease (STD) characterized by perivascular infiltration of inflammatory cells, vascular leakage, swelling and proliferation of endothelial cells (ECs). The endothelium lining blood and lymphatic vessels is a key barrier separating body fluids from host tissues and is a major target of T. pallidum. In this review, we focus on how T. pallidum establish intimate interactions with ECs, triggering endothelial dysfunction such as endothelial inflammation, abnormal repairment and damage of ECs. In addition, we summarize that migration and invasion of T. pallidum across vascular ECs may occur through two pathways. These two mechanisms of transendothelial migration are paracellular and cholesterol-dependent, respectively. Herein, clarifying the relationship between T. pallidum and endothelial dysfunction is of great significance to provide novel strategies for diagnosis and prevention of syphilis, and has a great potential prospect of clinical application.

12.
Sensors (Basel) ; 24(5)2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38474909

RESUMO

Simultaneous Localization and Mapping (SLAM), as one of the core technologies in intelligent robotics, has gained substantial attention in recent years. Addressing the limitations of SLAM systems in dynamic environments, this research proposes a system specifically designed for plant factory transportation environments, named GY-SLAM. GY-SLAM incorporates a lightweight target detection network, GY, based on YOLOv5, which utilizes GhostNet as the backbone network. This integration is further enhanced with CoordConv coordinate convolution, CARAFE up-sampling operators, and the SE attention mechanism, leading to simultaneous improvements in detection accuracy and model complexity reduction. While mAP@0.5 increased by 0.514% to 95.364, the model simultaneously reduced the number of parameters by 43.976%, computational cost by 46.488%, and model size by 41.752%. Additionally, the system constructs pure static octree maps and grid maps. Tests conducted on the TUM dataset and a proprietary dataset demonstrate that GY-SLAM significantly outperforms ORB-SLAM3 in dynamic scenarios in terms of system localization accuracy and robustness. It shows a remarkable 92.59% improvement in RMSE for Absolute Trajectory Error (ATE), along with a 93.11% improvement in RMSE for the translational drift of Relative Pose Error (RPE) and a 92.89% improvement in RMSE for the rotational drift of RPE. Compared to YOLOv5s, the GY model brings a 41.5944% improvement in detection speed and a 17.7975% increase in SLAM operation speed to the system, indicating strong competitiveness and real-time capabilities. These results validate the effectiveness of GY-SLAM in dynamic environments and provide substantial support for the automation of logistics tasks by robots in specific contexts.

13.
Sensors (Basel) ; 24(4)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38400507

RESUMO

There has been a significant shift in research focus in recent years toward laser-induced graphene (LIG), which is a high-performance material with immense potential for use in energy storage, ultrahydrophobic water applications, and electronic devices. In particular, LIG has demonstrated considerable potential in the field of high-precision human motion posture capture using flexible sensing materials. In this study, we investigated the surface morphology evolution and performance of LIG formed by varying the laser energy accumulation times. Further, to capture human motion posture, we evaluated the performance of highly accurate flexible wearable sensors based on LIG. The experimental results showed that the sensors prepared using LIG exhibited exceptional flexibility and mechanical performance when the laser energy accumulation was optimized three times. They exhibited remarkable attributes, such as high sensitivity (~41.4), a low detection limit (0.05%), a rapid time response (response time of ~150 ms; relaxation time of ~100 ms), and excellent response stability even after 2000 s at a strain of 1.0% or 8.0%. These findings unequivocally show that flexible wearable sensors based on LIG have significant potential for capturing human motion posture, wrist pulse rates, and eye blinking patterns. Moreover, the sensors can capture various physiological signals for pilots to provide real-time capturing.


Assuntos
Grafite , Dispositivos Eletrônicos Vestíveis , Humanos , Captura de Movimento , Eletrônica , Lasers
14.
J Sci Food Agric ; 104(1): 518-529, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37661343

RESUMO

BACKGROUND: Phenolic acids are widespread in foods and are beneficial to human health. However, the role of metal ions in influencing the binding of proteins with phenolic acids that contain the same parent nucleus structure remains unclear. This study investigated the inhibitory effect of caffeic acid (CA) and chlorogenic acid (CHA) on α-glucosidase and the biological effect of copper on this process. RESULTS: It was found that the esterification of CA with quinic acid could increase the fluorescence quenching, conformational change, and inhibitory effect of CHA on α-glucosidase. Copper ions reduced their fluorescence quenching and conformation-changing ability by binding to the neighboring phenolic hydroxyl group but also increased their ability to alter secondary structure and to inhibit α-glucosidase and in vitro anti-glycation. CONCLUSION: Overall, this study shows that the binding of copper ions to the phenolic hydroxyl group adjacent to CA and CHA synergistically inhibited α-glucosidase. The findings will offer a theoretical basis for investigating the properties of metal ions and phenolic acid in food chemistry and their potential applications in the prevention and treatment of diabetes mellitus. © 2023 Society of Chemical Industry.


Assuntos
Ácido Clorogênico , Cobre , Hidroxibenzoatos , Humanos , Ácido Clorogênico/química , Cobre/metabolismo , alfa-Glucosidases/metabolismo , Ácidos Cafeicos/química , Íons , Inibidores de Glicosídeo Hidrolases/farmacologia
15.
Angew Chem Int Ed Engl ; : e202408861, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898541

RESUMO

Despite various efforts to optimize the near-infrared (NIR) performance of perylene diimide (PDI) derivatives for bio-imaging, convenient and efficient strategies to amplify the fluorescence of PDI derivatives in biological environment and the intrinsic mechanism studies are still lacking. Herein, we propose an alkyl-doping strategy to amplify the fluorescence of PDI derivative-based nanoparticles for improved NIR fluorescence imaging. The developed PDI derivative, OPE-PDI, shows much brighter in n-Hexane (HE) compared with that in other organic media, and the excited state dynamics investigation experimentally elucidates the solvent effect-induced suppression of intermolecular energy transfer and intramolecular nonradiative decay as the underlying mechanism for the fluorescence improvement. Theoretical calculations reveal the lowest reorganization energies of OPE-PDI in HE among various solvents, indicating the effectively suppressed conformational relaxation to support the strongest radiative decay. Inspired by this, an alkyl atmosphere mimicking HE is constructed by incorporating the octadecane into OPE-PDI-based nanoparticles, permitting up to 3-fold fluorescence improvement compared with the counterpart nanoparticles. Owing to the merits of high brightness, anti-photobleaching, and low biotoxicity for the optimal nanoparticles, they have been employed for probing and long-term monitoring of tumor. This work highlights a facile strategy for the fluorescence enhancement of PDI derivative-based nanoparticles.

16.
Angew Chem Int Ed Engl ; : e202410130, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38932636

RESUMO

In contrast to the self-assembly of homosupramolecules, the self-assembly of heterosupramolecules is more challenging and significant in various fields. Herein, we design and investigate a cucurbit[8]uril-mediated heterodimerisation using an arene-fluoroarene strategy. Moreover, the resulting heteroternary complex is found to be able to undergo a photoinduced [2+2] heterocycloaddition, resulting in the formation of an unexpected [2]rotaxane structure. This work demonstrates a novel supramolecular heterodimerisation system, not only contributing to the development of photoisomerisation systems, but also enriching synthetic methodologies of mechanically interlocked molecules.

17.
J Neurochem ; 165(6): 842-859, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36971732

RESUMO

Schwann cells play an essential role in peripheral nerve regeneration by generating a favorable microenvironment. Gastric inhibitory peptide/gastric inhibitory peptide receptor (GIP/GIPR) axis deficiency leads to failure of sciatic nerve repair. However, the underlying mechanism remains elusive. In this study, we surprisingly found that GIP treatment significantly enhances the migration of Schwann cells and the formation of Schwann cell cords during recovery from sciatic nerve injury in rats. We further revealed that GIP and GIPR levels in Schwann cells were low under normal conditions, and significantly increased after injury demonstrated by real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Wound healing and Transwell assays showed that GIP stimulation and GIPR silencing could affect Schwann cell migration. In vitro and in vivo mechanistic studies based on interference experiment revealed that GIP/GIPR might promote mechanistic target of rapamycin complex 2 (mTORC2) activity, thus facilitating cell migration; Rap1 activation might be involved in this process. Finally, we retrieved the stimulatory factors responsible for GIPR induction after injury. The results indicate that sonic hedgehog (SHH) is a potential candidate whose expression increased upon injury. Luciferase and chromatin immunoprecipitation (ChIP) assays showed that Gli3, the target transcription factor of the SHH pathway, dramatically augmented GIPR expression. Additionally, in vivo inhibition of SHH could effectively reduce GIPR expression after sciatic nerve injury. Collectively, our study reveals the importance of GIP/GIPR signaling in Schwann cell migration, providing a therapeutic avenue toward peripheral nerve injury.


Assuntos
Traumatismos dos Nervos Periféricos , Neuropatia Ciática , Ratos , Animais , Proteínas Hedgehog/metabolismo , Traumatismos dos Nervos Periféricos/metabolismo , Transdução de Sinais/fisiologia , Neuropatia Ciática/metabolismo , Nervo Isquiático/lesões , Receptores de Peptídeos/metabolismo , Células de Schwann/metabolismo
18.
Mol Cancer ; 22(1): 110, 2023 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-37443114

RESUMO

BACKGROUND: Drugs targeting the spindle assembly checkpoint (SAC), such as inhibitors of Aurora kinase B (AURKB) and dual specific protein kinase TTK, are in different stages of clinical development. However, cell response to SAC abrogation is poorly understood and there are no markers for patient selection. METHODS: A panel of 53 tumor cell lines of different origins was used. The effects of drugs were analyzed by MTT and flow cytometry. Copy number status was determined by FISH and Q-PCR; mRNA expression by nCounter and RT-Q-PCR and protein expression by Western blotting. CRISPR-Cas9 technology was used for gene knock-out (KO) and a doxycycline-inducible pTRIPZ vector for ectopic expression. Finally, in vivo experiments were performed by implanting cultured cells or fragments of tumors into immunodeficient mice. RESULTS: Tumor cells and patient-derived xenografts (PDXs) sensitive to AURKB and TTK inhibitors consistently showed high expression levels of BH3-interacting domain death agonist (BID), while cell lines and PDXs with low BID were uniformly resistant. Gene silencing rendered BID-overexpressing cells insensitive to SAC abrogation while ectopic BID expression in BID-low cells significantly increased sensitivity. SAC abrogation induced activation of CASP-2, leading to cleavage of CASP-3 and extensive cell death only in presence of high levels of BID. Finally, a prevalence study revealed high BID mRNA in 6% of human solid tumors. CONCLUSIONS: The fate of tumor cells after SAC abrogation is driven by an AURKB/ CASP-2 signaling mechanism, regulated by BID levels. Our results pave the way to clinically explore SAC-targeting drugs in tumors with high BID expression.


Assuntos
Neoplasias , Proteínas Serina-Treonina Quinases , Humanos , Animais , Camundongos , Proteínas Serina-Treonina Quinases/genética , Aurora Quinase B/genética , Aurora Quinase B/metabolismo , Pontos de Checagem da Fase M do Ciclo Celular , Linhagem Celular Tumoral , RNA Mensageiro , Neoplasias/tratamento farmacológico , Neoplasias/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas de Ciclo Celular/genética
19.
Hum Brain Mapp ; 44(18): 6429-6438, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37909379

RESUMO

This study aims to explore the changes of the aspartate (Asp) level in the medial-prefrontal cortex (mPFC) of subjects with nicotine addiction (nicotine addicts [NAs]) using the J-edited 1 H MR spectroscopy (MRS), which may provide a positive imaging evidence for intervention of NA. From March to August 2022, 45 males aged 40-60 years old were recruited from Henan Province, including 21 in NA and 24 in nonsmoker groups. All subjects underwent routine magnetic resonance imaging (MRI) and J-edited MRS scans on a 3.0 T MRI scanner. The Asp level in mPFC was quantified with reference to the total creatine (Asp/Cr) and water (Aspwater-corr , with correction of the brain tissue composition) signals, respectively. Two-tailed independent samples t-test was used to analyze the differences in levels of Asp and other coquantified metabolites (including total N-acetylaspartate [tNAA], total cholinine [tCho], total creatine [tCr], and myo-Inositol [mI]) between the two groups. Finally, the correlations of the Asp level with clinical characteristic assessment scales were performed using the Spearman criteria. Compared with the control group (n = 22), NAs (n = 18) had higher levels of Asp (Asp/Cr: p = .005; Aspwater-corr : p = .004) in the mPFC, and the level of Asp was positively correlated with the daily smoking amount (Asp/Cr: p < .001; Aspwater-corr : p = .004). No significant correlation was found between the level of Asp and the years of nicotine use, Fagerstrom Nicotine Dependence (FTND), Russell Reason for Smoking Questionnaire (RRSQ), or Barratt Impulsivity Scale (BIS-11) score. The elevated Asp level was observed in mPFC of NAs in contrast to nonsmokers, and the Asp level was positively correlated with the amount of daily smoking, which suggests that nicotine addiction may result in elevated Asp metabolism in the human brain.


Assuntos
Nicotina , Tabagismo , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Nicotina/metabolismo , Ácido Aspártico/metabolismo , Tabagismo/diagnóstico por imagem , Creatina/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Imageamento por Ressonância Magnética , Inositol/metabolismo , Córtex Pré-Frontal/metabolismo , Água/metabolismo
20.
Biochem Biophys Res Commun ; 670: 1-11, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37271034

RESUMO

Primary liver hepatocellular carcinoma (HCC) is the third most deadly malignancy worldwide,in part, because it is often diagnosed at an advanced stage. Thus, molecular markers are needed to aid in the early diagnosis and treatment of HCC. Expression of abnormal mesoderm posterior-1 (MESP1) promotes tumorigenesis; however,its role in the regulation of HCC proliferation, apoptosis,and invasion is unknown. Here,we analyzed data in The Cancer Genome Atlas (TCGA)and Genotype Tissue Expression (GTEx) databases on the pan-cancer expression of MESP1 and its relationship with clinical characteristics and prognosis of patients with HCC. The expression of MESP1 was measured in 48 HCC tissues using immunohistochemical staining,and the results were correlated with clinical stage, tumor differentiation, tumor size,and metastasis. MESP1 expression was downregulated using small interfering RNA (siRNA) in the HCC cell lines HepG2 and Hep3B,and cell viability, proliferation,cell cycle, apoptosis,and invasion were analyzed. Finally,we also evaluated the tumor suppression effect of MESP1 downregulation combined with 5-fluorouracil (5-FU) treatment. Our results showed that MESP1 is a pan-oncogene associated with poor prognosis in patients with HCC. siRNA-induced downregulation of MESP1 expression in HepG2 and Hep3B cells exhibited downregulation of ß-catenin and GSK3ß expression 48h after transfection, along with an increase in apoptosis rate, arrest in the G1-S phase,and a decrease in mitochondrial membrane potential. Moreover,the expression levels of c-Myc, PARP1, bcl2, Snail1, MMP9, and immune checkpoint genes (TIGIT, CTLA4,LAG3,CD274,and PDCD1) were downregulated, while those of caspase3 and E-cadherin were upregulated. Tumor cells also showed decreased migration ability. Furthermore, siRNA interference of MESP1 expression combined with 5-FU-treatment of HCC cells significantly enhanced the G1-S phase block and apoptosis. MESP1 showed an aberrant high expression in HCC and was associated with poor clinical outcomes; therefore, MESP1 may be a potential target for the diagnosis and treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fluoruracila/farmacologia , Transição Epitelial-Mesenquimal/genética , Linhagem Celular Tumoral , RNA Interferente Pequeno/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Movimento Celular , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
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