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1.
Adv Exp Med Biol ; 1460: 199-229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39287853

RESUMO

The action of protein kinases and protein phosphatases is essential for multiple physiological responses. Each protein kinase displays its own unique substrate specificity and a regulatory mechanism that may be modulated by association with other proteins. Protein kinases are classified as dual-specificity kinases and dual-specificity phosphatases. Dual-specificity phosphatases are important signal transduction enzymes that regulate various cellular processes in coordination with protein kinases and play an important role in obesity. Impairment of insulin signaling in obesity is largely mediated by the activation of the inhibitor of kappa B-kinase beta and the c-Jun N-terminal kinase (JNK). Oxidative stress and endoplasmic reticulum (ER) stress activate the JNK pathway which suppresses insulin biosynthesis. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) are important for proper regulation of glucose metabolism in mammals at both the hormonal and cellular levels. Additionally, obesity-activated calcium/calmodulin dependent-protein kinase II/p38 suppresses insulin-induced protein kinase B phosphorylation by activating the ER stress effector, activating transcription factor-4. To alleviate lipotoxicity and insulin resistance, promising targets are pharmacologically inhibited. Nifedipine, calcium channel blocker, stimulates lipogenesis and adipogenesis by downregulating AMPK and upregulating mTOR, which thereby enhances lipid storage. Contrary to the nifedipine, metformin activates AMPK, increases fatty acid oxidation, suppresses fatty acid synthesis and deposition, and thus alleviates lipotoxicity. Obese adults with vascular endothelial dysfunction have greater endothelial cells activation of unfolded protein response stress sensors, RNA-dependent protein kinase-like ER eukaryotic initiation factor-2 alpha kinase (PERK), and activating transcription factor-6. The transcriptional regulation of adipogenesis in obesity is influenced by AGC (protein kinase A (PKA), PKG, PKC) family signaling kinases. Obesity may induce systemic oxidative stress and increase reactive oxygen species in adipocytes. An increase in intracellular oxidative stress can promote PKC-ß activation. Activated PKC-ß induces growth factor adapter Shc phosphorylation. Shc-generated peroxides reduce mitochondrial oxygen consumption and enhance triglyceride accumulation and lipotoxicity. Liraglutide attenuates mitochondrial dysfunction and reactive oxygen species generation. Co-treatment of antiobesity and antidiabetic herbal compound, berberine with antipsychotic drug olanzapine decreases the accumulation of triglyceride. While low-dose rapamycin, metformin, amlexanox, thiazolidinediones, and saroglitazar protect against insulin resistance, glucagon-like peptide-1 analog liraglutide inhibits palmitate-induced inflammation by suppressing mTOR complex 1 (mTORC1) activity and protects against lipotoxicity.


Assuntos
Obesidade , Humanos , Obesidade/metabolismo , Obesidade/tratamento farmacológico , Animais , Proteínas Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Terapia de Alvo Molecular , Resistência à Insulina , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
2.
Leg Med (Tokyo) ; 71: 102526, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39293288

RESUMO

E-scooters have become increasingly popular for short-distance travel in urban areas, but this rise in usage also brings about an increased risk of accidents. Studies have shown that approximately 40% of electric scooter accident victims admitted to hospitals suffer head injuries. Therefore, it is crucial to implement safety measures and improve safety systems and equipment to mitigate these risks. One approach to gaining insights into the injuries users face is through simulations using the multi-body method. This method allows for the reconstruction of accidents by modeling and analyzing the dynamic behavior of interconnected bodies. This study aims to assess the impacts on the user's head and the injuries they may sustain in electric scooter accidents using numerical methods. Initially, a reference scenario was established based on a YouTube video, with the assumption that the user was an average-height man. Simulations were conducted for various percentiles, including both males and females. Different velocities were simulated to determine the threshold velocity at which survival becomes practically impossible. Two scenarios were considered: one where the car braked for 0.333 s and another where the distance between the start the braking task and the collision was kept constant. The location of the first head impact on the vehicle was also examined. Injury assessment was conducted using two criteria: Head Injury Criterion (HIC) and Brain Injury Criterion (BrIC). The study found that smaller individuals are more vulnerable to severe injuries, and higher car velocities correlate with more severe user injuries. Furthermore, the location of the first impact varies between genders, with women more likely to experience impacts in the lower part of the windshield, while men tend to experience impacts in the central zone. This study highlights the importance of considering user characteristics and accident dynamics in assessing injury risks associated with e-scooters.

3.
Transl Cancer Res ; 13(8): 4315-4323, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39262466

RESUMO

Background: Pancreatic neuroendocrine neoplasm (pNEN) poses significant challenges in clinical management due to their heterogeneity and limited treatment options. In this study, we investigated the potential of simvastatin (SIM) as an anti-tumor agent in pNEN. Methods: We conducted cell culture experiments using QGP-1 and BON-1 cell lines and assessed cell viability, proliferation, migration, and invasion following SIM treatment. To further validate our findings, we performed in vivo experiments using a mouse xenograft model. Additionally, we investigated the underlying molecular mechanisms by analyzing changes in cell cycle progression, apoptosis, and signaling pathways. Results: SIM treatment suppresses pNEN growth both in vitro and in vivo, and led to G1 phase arrest in QGP-1 cells. In contrast, SIM affected both the G1-S and G2-M phase transitions in the BON-1 cell line and induced apoptosis, indicating diverse mechanisms of action. Furthermore, SIM treatment resulted in decreased expression of mutant p53 (mutp53) in BON-1 cells, suggesting a potential therapeutic strategy targeting mutp53. Modulation of the MAPK pathway was also implicated in QGP-1 cells. Conclusions: Our study highlights SIM as a promising candidate for pNEN treatment by inducing cell cycle arrest or apoptosis, potentially through the p53 and MAPK pathways. Further research is warranted to fully elucidate SIM's mechanisms of action and evaluate its therapeutic potential in clinical settings.

4.
J Mol Biol ; 436(22): 168768, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39216515

RESUMO

Neurofibromin (Nf1) is a giant multidomain protein encoded by the tumour-suppressor gene NF1. NF1 is mutated in a common genetic disease, neurofibromatosis type I (NF1), and in various cancers. The protein has a Ras-GAP (GTPase activating protein) activity but is also connected to diverse signalling pathways through its SecPH domain, which interacts with lipids and different protein partners. We previously showed that Nf1 partially colocalized with the ProMyelocytic Leukemia (PML) protein in PML nuclear bodies, hotspots of SUMOylation, thereby suggesting the potential SUMOylation of Nf1. Here, we demonstrate that the full-length isoform 2 and a SecPH fragment of Nf1 are substrates of the SUMO pathway and identify a well-defined SUMOylation profile of SecPH with two main modified lysines. One of these sites, K1731, is highly conserved and surface-exposed. Despite the presence of an inverted SUMO consensus motif surrounding K1731, and a potential SUMO-interacting motif (SIM) within SecPH, we show that neither of these elements is necessary for K1731 SUMOylation, which is also independent of Ubc9 SUMOylation on K14. A 3D model of an interaction between SecPH and Ubc9 centred on K1731, combined with site-directed mutagenesis, identifies specific structural elements of SecPH required for K1731 SUMOylation, some of which are affected in reported NF1 pathogenic variants. This work provides a new example of SUMOylation dependent on the tertiary rather than primary protein structure surrounding the modified site, expanding our knowledge of mechanisms governing SUMOylation site selection.

5.
Eur J Pharm Sci ; 202: 106881, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39179162

RESUMO

The advanced age population may be susceptible to an increased risk of adverse effects due to increased drug exposure after oral dosing. Factors such as high-interindividual variability and lack of data has led to poor characterization of absorption's role in pharmacokinetic changes in this population. Physiologically based pharmacokinetic (PBPK) models are increasingly being used during the drug development process, as their unique qualities are advantageous in atypical scenarios such as drug-drug interactions or special populations such as older people. Along with relying on various sources of data, auxiliary tools including parameter estimation and sensitivity analysis techniques are employed to support model development and other applications. However, sensitivity analyses have mostly been limited to localized techniques in the majority of reported PBPK models using them. This is disadvantageous, since local sensitivity analyses are unsuitable for risk analysis, which require assessment of parametric interactions and proper coverage of the input space to better estimate and subsequently mitigate the effects of the phenomenon of interest. For this reason, this study seeks to integrate a global sensitivity analysis screening method with PBPK models based in PK-Sim® to characterize the consequences of potential changes in absorption that are often associated with advanced age. The Elementary Effects (Morris) method and visualization of the results are implemented in R and three model drugs representing Biopharmaceutical Classification System classes I-III that are expected to exhibit some sensitivity to three age-associated hypotheses were successfully tested.


Assuntos
Modelos Biológicos , Humanos , Farmacocinética , Simulação por Computador , Preparações Farmacêuticas/metabolismo , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Fatores Etários , Idoso , Interações Medicamentosas/fisiologia , Absorção Intestinal/fisiologia
6.
J Biophotonics ; : e202400154, 2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39098050

RESUMO

In this study, we introduced a novel dual-laser multi-color imaging system. Integrated with a multi-channel filter wheel, this system compared three spectral decontamination algorithms (nonnegative matrix factorization [NMF], RCAN, and PICASSO) showcasing its efficacy in achieving four-color imaging with only two laser sources. Combined with a reliable image reconstruction algorithm, the spatial resolution of four channels super-resolution four-color images reached 130, 125, 133, and 132 nm, respectively. Lipid droplets, mitochondria, lysosomes, and nuclei from the mouse hepatocytes (AML12), human neuroblastoma cells (SH-SY5Y), mouse hippocampal neuronal cells (HT-22), and immortalized murine bone marrow-derived macrophages were imaged. At the same time, the chromatin condensation, nuclear contraction, DNA fragmentation, apoptotic body formation, as well as the fusion of Mito and Lyso involved in mitochondrial autophagy were observed in HT-22 and SH-SY5Y cells suffering oxidative stress. Our multi-color SIM imaging system establishes a powerful platform for dynamic organelle studies and other high-resolution investigations in live cells.

7.
Sci Rep ; 14(1): 19269, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164261

RESUMO

This study aimed to develop a physiologically based pharmacokinetic/pharmacodynamic model (PBPK/PD) of meropenem for critically ill patients. A PBPK model of meropenem in healthy adults was established using PK-Sim software and subsequently extrapolated to critically ill patients based on anatomic and physiological parameters. The mean fold error (MFE) and geometric mean fold error (GMFE) methods were used to compare the differences between predicted and observed values of pharmacokinetic parameters Cmax, AUC0-∞, and CL to evaluate the accuracy of the PBPK model. The model was verified using meropenem plasma samples obtained from Intensive Care Unit (ICU) patients, which were determined by HPLC-MS/MS. After that, the PBPK model was combined with a PKPD model, which was developed based on f%T > MIC. Monte Carlo simulation was utilized to calculate the probability of target attainment (PTA) in patients. The developed PBPK model successfully predicted the meropenem disposition in critically ill patients, wherein the MFE average and GMFE of all predicted PK parameters were within the 1.25-fold error range. The therapeutic drug monitoring (TDM) of meropenem was conducted with 92 blood samples from 31 ICU patients, of which 71 (77.17%) blood samples were consistent with the simulated value. The TDM results showed that meropenem PBPK modeling is well simulated in critically ill patients. Monte Carlo simulations showed that extended infusion and frequent administration were necessary to achieve curative effect for critically ill patients, whereas excessive infusion time (> 4 h) was unnecessary. The PBPK/PD modeling incorporating literature and prospective study data can predict meropenem pharmacokinetics in critically ill patients correctly. Our study provides a reference for dose adjustment in critically ill patients.


Assuntos
Antibacterianos , Estado Terminal , Meropeném , Meropeném/farmacocinética , Meropeném/administração & dosagem , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Antibacterianos/farmacocinética , Antibacterianos/administração & dosagem , Adulto , Idoso , Modelos Biológicos , Método de Monte Carlo , Monitoramento de Medicamentos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana
8.
J Clin Pharmacol ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092894

RESUMO

Dosing vancomycin for critically ill neonates is challenging owing to substantial alterations in pharmacokinetics (PKs) caused by variability in physiology, disease, and clinical interventions. Therefore, an adequate PK model is needed to characterize these pathophysiological changes. The intent of this study was to develop a physiologically based pharmacokinetic (PBPK) model that reflects vancomycin PK and pathophysiological changes in neonates under intensive care. PK-sim software was used for PBPK modeling. An adult model (model 0) was established and verified using PK profiles from previous studies. A neonatal model (model 1) was then extrapolated from model 0 by scaling age-dependent parameters. Another neonatal model (model 2) was developed based not only on scaled age-dependent parameters but also on quantitative information on pathophysiological changes obtained via a comprehensive literature search. The predictive performances of models 1 and 2 were evaluated using a retrospectively collected dataset from neonates under intensive care (chictr.org.cn, ChiCTR1900027919), comprising 65 neonates and 92 vancomycin serum concentrations. Integrating literature-based parameter changes related to hypoalbuminemia, small-for-gestational-age, and co-medication, model 2 offered more optimized precision than model 1, as shown by a decrease in the overall mean absolute percentage error (50.6% for model 1; 37.8% for model 2). In conclusion, incorporating literature-based pathophysiological changes effectively improved PBPK modeling for critically ill neonates. Furthermore, this model allows for dosing optimization before serum concentration measurements can be obtained in clinical practice.

9.
Cell Genom ; 4(8): 100609, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39019033

RESUMO

Little is known about the role of non-coding regions in the etiology of autism spectrum disorder (ASD). We examined three classes of non-coding regions: human accelerated regions (HARs), which show signatures of positive selection in humans; experimentally validated neural VISTA enhancers (VEs); and conserved regions predicted to act as neural enhancers (CNEs). Targeted and whole-genome analysis of >16,600 samples and >4,900 ASD probands revealed that likely recessive, rare, inherited variants in HARs, VEs, and CNEs substantially contribute to ASD risk in probands whose parents share ancestry, which enriches for recessive contributions, but modestly contribute, if at all, in simplex family structures. We identified multiple patient variants in HARs near IL1RAPL1 and in VEs near OTX1 and SIM1 and showed that they change enhancer activity. Our results implicate both human-evolved and evolutionarily conserved non-coding regions in ASD risk and suggest potential mechanisms of how regulatory changes can modulate social behavior.


Assuntos
Transtorno do Espectro Autista , Humanos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/epidemiologia , Predisposição Genética para Doença , Elementos Facilitadores Genéticos/genética , Masculino , Evolução Molecular , Feminino
10.
Front Bioeng Biotechnol ; 12: 1334643, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948382

RESUMO

The simulation-to-reality (sim2real) problem is a common issue when deploying simulation-trained models to real-world scenarios, especially given the extremely high imbalance between simulation and real-world data (scarce real-world data). Although the cycle-consistent generative adversarial network (CycleGAN) has demonstrated promise in addressing some sim2real issues, it encounters limitations in situations of data imbalance due to the lower capacity of the discriminator and the indeterminacy of learned sim2real mapping. To overcome such problems, we proposed the imbalanced Sim2Real scheme (ImbalSim2Real). Differing from CycleGAN, the ImbalSim2Real scheme segments the dataset into paired and unpaired data for two-fold training. The unpaired data incorporated discriminator-enhanced samples to further squash the solution space of the discriminator, for enhancing the discriminator's ability. For paired data, a term targeted regression loss was integrated to ensure specific and quantitative mapping and further minimize the solution space of the generator. The ImbalSim2Real scheme was validated through numerical experiments, demonstrating its superiority over conventional sim2real methods. In addition, as an application of the proposed ImbalSim2Real scheme, we designed a finger joint stiffness self-sensing framework, where the validation loss for estimating real-world finger joint stiffness was reduced by roughly 41% compared to the supervised learning method that was trained with scarce real-world data and by 56% relative to the CycleGAN trained with the imbalanced dataset. Our proposed scheme and framework have potential applicability to bio-signal estimation when facing an imbalanced sim2real problem.

11.
J Neurochem ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946488

RESUMO

A growth cone is a highly motile tip of an extending axon that is crucial for neural network formation. Three-dimensional-structured illumination microscopy, a type of super-resolution light microscopy with a resolution that overcomes the optical diffraction limitation (ca. 200 nm) of conventional light microscopy, is well suited for studying the molecular dynamics of intracellular events. Using this technique, we discovered a novel type of filopodia distributed along the z-axis ("z-filopodia") within the growth cone. Z-filopodia were typically oriented in the direction of axon growth, not attached to the substratum, protruded spontaneously without microtubule invasion, and had a lifetime that was considerably shorter than that of conventional filopodia. Z-filopodia formation and dynamics were regulated by actin-regulatory proteins, such as vasodilator-stimulated phosphoprotein, fascin, and cofilin. Chromophore-assisted laser inactivation of cofilin induced the rapid turnover of z-filopodia. An axon guidance receptor, neuropilin-1, was concentrated in z-filopodia and was transported together with them, whereas its ligand, semaphorin-3A, was selectively bound to them. Membrane domains associated with z-filopodia were also specialized and resembled those of lipid rafts, and their behaviors were closely related to those of neuropilin-1. The results suggest that z-filopodia have unique turnover properties, and unlike xy-filopodia, do not function as force-generating structures for axon extension.

12.
Acta Crystallogr C Struct Chem ; 80(Pt 8): 349-356, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38984908

RESUMO

The synthesis, crystal structure and magnetic properties of an oxamate-containing erbium(III) complex, namely, tetrabutylammonium aqua[N-(2,4,6-trimethylphenyl)oxamato]erbium(III)-dimethyl sulfoxide-water (1/3/1.5), (C16H36N)[Er(C11H12NO3)4(H2O)]·3C2H6OS·1.5H2O or n-Bu4N[Er(Htmpa)4(H2O)]·3DMSO·1.5H2O (1), are reported. The crystal structure of 1 reveals the occurrence of an erbium(III) ion, which is surrounded by four N-phenyl-substituted oxamate ligands and one water molecule in a nine-coordinated environment, together with one tetrabutylammonium cation acting as a counter-ion, and one water and three dimethyl sulfoxide (DMSO) molecules of crystallization. Variable-temperature static (dc) and dynamic (ac) magnetic measurements were carried out for this mononuclear complex, revealing that it behaves as a field-induced single-ion magnet (SIM) below 5.0 K.

13.
Int J Mol Sci ; 25(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38891895

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive degeneration of upper and lower motor neurons (MNs) in the brain and spinal cord, leading to progressive paralysis and death. Increasing evidence indicates that neuroinflammation plays an important role in ALS's pathogenesis and disease progression. Neuroinflammatory responses, primarily driven by activated microglia and astrocytes, and followed by infiltrating peripheral immune cells, contribute to exacerbate/accelerate MN death. In particular, the role of the microglia in ALS remains unclear, partly due to the lack of experimental models that can fully recapitulate the complexity of ALS's pathology. In this study, we developed and characterized a microglial cell line, SIM-A9-expressing human mutant protein Cu+/Zn+ superoxide dismutase_1 (SIM-A9hSOD1(G93A)), as a suitable model in vitro mimicking the microglia activity in ALS. The expression of hSOD1(G93A) in SIM-A9 cells induced a change in their metabolic activity, causing polarization into a pro-inflammatory phenotype and enhancing reactive oxygen species production, which is known to activate cell death processes and apoptosis. Afterward, we used our microglial model as an experimental set-up to investigate the therapeutic action of extracellular vesicles isolated from adipose mesenchymal stem cells (ASC-EVs). ASC-EVs represent a promising therapeutic treatment for ALS due to their neuroprotective and immunomodulatory properties. Here, we demonstrated that treatment with ASC-EVs is able to modulate activated ALS microglia, reducing their metabolic activity and polarizing their phenotype toward an anti-inflammatory one through a mechanism of reduction of reactive oxygen species.


Assuntos
Esclerose Lateral Amiotrófica , Vesículas Extracelulares , Células-Tronco Mesenquimais , Microglia , Superóxido Dismutase-1 , Esclerose Lateral Amiotrófica/terapia , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Vesículas Extracelulares/metabolismo , Microglia/metabolismo , Células-Tronco Mesenquimais/metabolismo , Humanos , Superóxido Dismutase-1/metabolismo , Superóxido Dismutase-1/genética , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo
14.
Front Bioeng Biotechnol ; 12: 1386874, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919383

RESUMO

Musculoskeletal simulations can be used to estimate biomechanical variables like muscle forces and joint torques from non-invasive experimental data using inverse and forward methods. Inverse kinematics followed by inverse dynamics (ID) uses body motion and external force measurements to compute joint movements and the corresponding joint loads, respectively. ID leads to residual forces and torques (residuals) that are not physically realistic, because of measurement noise and modeling assumptions. Forward dynamic simulations (FD) are found by tracking experimental data. They do not generate residuals but will move away from experimental data to achieve this. Therefore, there is a gap between reality (the experimental measurements) and simulations in both approaches, the sim2real gap. To answer (patho-) physiological research questions, simulation results have to be accurate and reliable; the sim2real gap needs to be handled. Therefore, we reviewed methods to handle the sim2real gap in such musculoskeletal simulations. The review identifies, classifies and analyses existing methods that bridge the sim2real gap, including their strengths and limitations. Using a systematic approach, we conducted an electronic search in the databases Scopus, PubMed and Web of Science. We selected and included 85 relevant papers that were sorted into eight different solution clusters based on three aspects: how the sim2real gap is handled, the mathematical method used, and the parameters/variables of the simulations which were adjusted. Each cluster has a distinctive way of handling the sim2real gap with accompanying strengths and limitations. Ultimately, the method choice largely depends on various factors: available model, input parameters/variables, investigated movement and of course the underlying research aim. Researchers should be aware that the sim2real gap remains for both ID and FD approaches. However, we conclude that multimodal approaches tracking kinematic and dynamic measurements may be one possible solution to handle the sim2real gap as methods tracking multimodal measurements (some combination of sensor position/orientation or EMG measurements), consistently lead to better tracking performances. Initial analyses show that motion analysis performance can be enhanced by using multimodal measurements as different sensor technologies can compensate each other's weaknesses.

15.
Pharmaceuticals (Basel) ; 17(6)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38931364

RESUMO

Statins function beyond regulating cholesterol and, when administered systemically, can promote wound healing. However, studies have yet to explore the topical use of statins for wound healing. The present study demonstrated the topical administration of SIM and aimed to formulate, evaluate, and optimize Simvastatin (SIM)-encapsulated liposome gel carrier systems to facilitate successful topical wound healing. Liposomes containing SIM were formulated and optimized via a response surface methodology (RSM) using the thin-film hydration method. The effects of formulation variables, including the 1,2-dioleoyloxy-3-trimethylammoniumpropan (DOTAP) concentration, Span 80 concentration, and cholesterol concentration, on zeta potential (mV), entrapment efficacy (%), and particle size (nm) were studied. The optimized liposome formulation (F-07) exhibited a zeta potential value of 16.56 ± 2.51 mV, revealing robust stability and a high SIM encapsulation efficiency of 95.6 ± 4.2%, whereas its particle size of 190.3 ± 3.3 nm confirmed its stability and structural integrity. The optimized liposome gel demonstrated pseudoplastic flow behavior. This property is advantageous in topical drug delivery systems because of its ease of application, improved spreadability, and enhanced penetration, demonstrating prolonged SIM release. The assessment of the wound healing efficacy of the optimized liposomal gel formulation demonstrated a substantial decrease in wound size in mice on the sixteenth day post-wounding. These findings suggest that the use of liposomal gels is a potential drug delivery strategy for incorporating SIM, thereby augmenting its effectiveness in promoting wound healing.

16.
Chembiochem ; 25(16): e202400404, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-38877380

RESUMO

In this study, super-resolution structured illumination microscope (SIM) was used to analyze molecular mechanism of endocytic acidification inhibitors in the SARS-CoV-2 pandemic, such as Chloroquine (CQ), Hydroxychloroquine (HCQ) and Bafilomycin A1 (BafA1). We fluorescently labeled the SARS-CoV-2 RBD and its receptor ACE2 protein with small molecule dyes. Utilizing SIM imaging, the real-time impact of inhibitors (BafA1, CQ, HCQ, Dynasore) on the RBD-ACE2 endocytotic process was dynamically tracked in living cells. Initially, the protein activity of RBD and ACE2 was ensured after being labeled. And then our findings revealed that these inhibitors could inhibit the internalization and degradation of RBD-ACE2 to varying degrees. Among them, 100 nM BafA1 exhibited the most satisfactory endocytotic inhibition (~63.9 %) and protein degradation inhibition (~97.7 %). And it could inhibit the fusion between endocytic vesicles in the living cells. Additionally, Dynasore, a widely recognized dynein inhibitor, also demonstrated cell acidification inhibition effects. Together, these inhibitors collectively hinder SARS-CoV-2 infection by inhibiting both the viral internalization and RNA release. The comprehensive evaluation of pharmacological mechanisms through super-resolution fluorescence imaging has laid a crucial theoretical foundation for the development of potential drugs to treat COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2 , Tratamento Farmacológico da COVID-19 , Cloroquina , Endossomos , Hidrazonas , Hidroxicloroquina , Macrolídeos , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Endossomos/metabolismo , Endossomos/efeitos dos fármacos , Humanos , Cloroquina/farmacologia , Cloroquina/química , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Macrolídeos/farmacologia , Macrolídeos/química , Hidroxicloroquina/farmacologia , Hidroxicloroquina/química , Hidrazonas/farmacologia , Hidrazonas/química , Endocitose/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , COVID-19/virologia , COVID-19/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Concentração de Íons de Hidrogênio , Internalização do Vírus/efeitos dos fármacos , Chlorocebus aethiops
17.
Adv Sci (Weinh) ; 11(30): e2308881, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38889239

RESUMO

With wireless multimodal locomotion capabilities, magnetic soft millirobots have emerged as potential minimally invasive medical robotic platforms. Due to their diverse shape programming capability, they can generate various locomotion modes, and their locomotion can be adapted to different environments by controlling the external magnetic field signal. Existing adaptation methods, however, are based on hand-tuned signals. Here, a learning-based adaptive magnetic soft millirobot multimodal locomotion framework empowered by sim-to-real transfer is presented. Developing a data-driven magnetic soft millirobot simulation environment, the periodic magnetic actuation signal is learned for a given soft millirobot in simulation. Then, the learned locomotion strategy is deployed to the real world using Bayesian optimization and Gaussian processes. Finally, automated domain recognition and locomotion adaptation for unknown environments using a Kullback-Leibler divergence-based probabilistic method are illustrated. This method can enable soft millirobot locomotion to quickly and continuously adapt to environmental changes and explore the actuation space for unanticipated solutions with minimum experimental cost.

18.
Genetics ; 227(3)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38713088

RESUMO

Protein synthesis underpins cell growth and controls when cells commit to a new round of cell division at a point in late G1 of the cell cycle called Start. Passage through Start also coincides with the duplication of the microtubule-organizing centers, the yeast spindle pole bodies, which will form the 2 poles of the mitotic spindle that segregates the chromosomes in mitosis. The conserved Mps1p kinase governs the duplication of the spindle pole body (SPB) in Saccharomyces cerevisiae. Here, we show that the MPS1 transcript has a short upstream open reading frame (uORF) that represses the synthesis of Mps1p. Mutating the MPS1 uORF makes the cells smaller, accelerates the appearance of Mps1p in late G1, and promotes completion of Start. Monitoring the SPB in the cell cycle using structured illumination microscopy revealed that mutating the MPS1 uORF enabled cells to duplicate their SPB earlier at a smaller cell size. The accelerated Start of MPS1 uORF mutants depends on the G1 cyclin Cln3p and the transcriptional repressor Whi5p but not on the Cln1,2p G1 cyclins. These results identify growth inputs in mechanisms that control duplication of the microtubule-organizing center and implicate these processes in the coupling of cell growth with division.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Corpos Polares do Fuso , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Corpos Polares do Fuso/metabolismo , Corpos Polares do Fuso/genética , Ciclinas/metabolismo , Ciclinas/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Fases de Leitura Aberta , Biossíntese de Proteínas , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Divisão Celular/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Regulação Fúngica da Expressão Gênica
19.
JMIR Form Res ; 8: e53608, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630517

RESUMO

BACKGROUND: Understanding the factors influencing individuals' health decisions is a dynamic research question. Particularly, after China announced the deregulation of the COVID-19 epidemic, health risks escalated rapidly. The convergence of "no longer controlled" viruses and the infodemic has created a distinctive social period during which multiple factors may have influenced people's decision-making. Among these factors, the precautionary intentions of older individuals, as a susceptible health group, deserve special attention. OBJECTIVE: This study aims to examine the intention of older adults to engage in preventive behaviors and the influencing factors, including social, media, and individual factors, within the context of the postepidemic era. Drawing upon the structural influence model of communication, this study tests the potential mediating roles of 3 different types of media exposure between cognitive and structural social capital and protective behavior intention, as well as the moderating role of negative emotions between social capital and media exposure. METHODS: In this study, a web survey was used to collect self-reported quantitative data on social capital, media exposure, negative emotions, and the intention to prevent COVID-19 among older adults aged ≥60 years (N=399) in China. RESULTS: The results indicate that cognitive social capital significantly influenced protective behavior intention (P<.001), with cell phone exposure playing an additional impactful role (P<.001). By contrast, newspaper and radio exposure and television exposure mediated the influence of structural social capital on protective behavior intention (P<.001). Furthermore, negative emotions played a moderating role in the relationship between cognitive social capital and cell phone exposure (P<.001). CONCLUSIONS: This study suggests that using tailored communication strategies across various media channels can effectively raise health awareness among older adults dealing with major pandemics in China, considering their diverse social capital characteristics and emotional states.

20.
Metabolites ; 14(4)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38668312

RESUMO

Orbitrap mass spectrometry in full scan mode enables the simultaneous detection of hundreds of metabolites and their isotope-labeled forms. Yet, sensitivity remains limiting for many metabolites, including low-concentration species, poor ionizers, and low-fractional-abundance isotope-labeled forms in isotope-tracing studies. Here, we explore selected ion monitoring (SIM) as a means of sensitivity enhancement. The analytes of interest are enriched in the orbitrap analyzer by using the quadrupole as a mass filter to select particular ions. In tissue extracts, SIM significantly enhances the detection of ions of low intensity, as indicated by improved signal-to-noise (S/N) ratios and measurement precision. In addition, SIM improves the accuracy of isotope-ratio measurements. SIM, however, must be deployed with care, as excessive accumulation in the orbitrap of similar m/z ions can lead, via space-charge effects, to decreased performance (signal loss, mass shift, and ion coalescence). Ion accumulation can be controlled by adjusting settings including injection time and target ion quantity. Overall, we suggest using a full scan to ensure broad metabolic coverage, in tandem with SIM, for the accurate quantitation of targeted low-intensity ions, and provide methods deploying this approach to enhance metabolome coverage.

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