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1.
bioRxiv ; 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38766098

RESUMO

Pain is a complex experience that remains largely unexplored in naturalistic contexts, hindering our understanding of its neurobehavioral representation in ecologically valid settings. To address this, we employed a multimodal, data-driven approach integrating intracranial electroencephalography, pain self-reports, and facial expression quantification to characterize the neural and behavioral correlates of naturalistic acute pain in twelve epilepsy patients undergoing continuous monitoring with neural and audiovisual recordings. High self-reported pain states were associated with elevated blood pressure, increased pain medication use, and distinct facial muscle activations. Using machine learning, we successfully decoded individual participants' high versus low self-reported pain states from distributed neural activity patterns (mean AUC = 0.70), involving mesolimbic regions, striatum, and temporoparietal cortex. High self-reported pain states exhibited increased low-frequency activity in temporoparietal areas and decreased high-frequency activity in mesolimbic regions (hippocampus, cingulate, and orbitofrontal cortex) compared to low pain states. This neural pain representation remained stable for hours and was modulated by pain onset and relief. Objective facial expression changes also classified self-reported pain states, with results concordant with electrophysiological predictions. Importantly, we identified transient periods of momentary pain as a distinct naturalistic acute pain measure, which could be reliably differentiated from affect-neutral periods using intracranial and facial features, albeit with neural and facial patterns distinct from self-reported pain. These findings reveal reliable neurobehavioral markers of naturalistic acute pain across contexts and timescales, underscoring the potential for developing personalized pain interventions in real-world settings.

2.
J Am Chem Soc ; 146(6): 3732-3741, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38301030

RESUMO

Semiconductor nanocrystals (NCs) offer prospective use as active optical elements in photovoltaics, light-emitting diodes, lasers, and photocatalysts due to their tunable optical absorption and emission properties, high stability, and scalable solution processing, as well as compatibility with additive manufacturing routes. Over the course of experiments, during device fabrication, or while in use commercially, these materials are often subjected to intense or prolonged electronic excitation and high carrier densities. The influence of such conditions on ligand integrity and binding remains underexplored. Here, we expose CdSe NCs to laser excitation and monitor changes in oleate that is covalently attached to the NC surface using nuclear magnetic resonance as a function of time and laser intensity. Higher photon doses cause increased rates of ligand loss from the particles, with upward of 50% total ligand desorption measured for the longest, most intense excitation. Surprisingly, for a range of excitation intensities, fragmentation of the oleate is detected and occurs concomitantly with formation of aldehydes, terminal alkenes, H2, and water. After illumination, NC size, shape, and bandgap remain constant although low-energy absorption features (Urbach tails) develop in some samples, indicating formation of substantial trap states. The observed reaction chemistry, which here occurs with low photon to chemical conversion efficiency, suggests that ligand reactivity may require examination for improved NC dispersion stability but can also be manipulated to yield desired photocatalytically accessed chemical species.

3.
Pediatr Dermatol ; 41(2): 284-288, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37723596

RESUMO

PHACE (posterior fossa malformations, hemangiomas, arterial anomalies, cardiac anomalies, eye anomalies) association has many recognized clinical features. A link between PHACE and non-vascular intracranial lesions has not been well-described. We report three pediatric patients with PHACE and non-vascular intracranial lesions.


Assuntos
Anormalidades Múltiplas , Coartação Aórtica , Anormalidades do Olho , Síndromes Neurocutâneas , Humanos , Criança , Lactente , Síndromes Neurocutâneas/diagnóstico , Síndromes Neurocutâneas/patologia , Coartação Aórtica/complicações , Coartação Aórtica/diagnóstico , Coartação Aórtica/patologia , Anormalidades do Olho/diagnóstico , Anormalidades do Olho/patologia
4.
Dent J (Basel) ; 11(10)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37886918

RESUMO

OBJECTIVES: Amid the COVID-19 pandemic, the transition to distance learning raised pertinent questions regarding advantages and challenges compared to traditional in-person learning. This study aimed to investigate dental students' perceptions of distance learning throughout the pandemic, examining its impact on their education. METHODS: This study employed a convergent mixed-methods design. Three online surveys were conducted in 2020, 2021, and 2022 to collect quantitative data. Additionally, qualitative semi-structured interviews were carried out in 2022. Interviews were recorded and transcribed; then, thematic analysis was performed following an inductive approach. RESULTS: As perceived by the participants, distance learning entails advantages and challenges. Initially, they felt uncertainty and negativity about the new environment with distance learning. However, their perceptions shifted positively as they adapted, even after returning to hybrid and in-person modules. Furthermore, most participants felt that distance learning is better suited for didactic content. It was suggested that didactic courses contain approximately 25-50% of online methods. CONCLUSIONS: Distance learning has provided valuable opportunities to reinforce curricula and improve learning efficacy during the pandemic. Our findings suggest that a hybrid learning model that combines traditional and distance modules appears to be an effective approach for future dental education.

5.
Nat Commun ; 14(1): 6169, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794035

RESUMO

Mucin-domain glycoproteins are densely O-glycosylated and play critical roles in a host of biological functions. In particular, the T cell immunoglobulin and mucin-domain containing family of proteins (TIM-1, -3, -4) decorate immune cells and act as key regulators in cellular immunity. However, their dense O-glycosylation remains enigmatic, primarily due to the challenges associated with studying mucin domains. Here, we demonstrate that the mucinase SmE has a unique ability to cleave at residues bearing very complex glycans. SmE enables improved mass spectrometric analysis of several mucins, including the entire TIM family. With this information in-hand, we perform molecular dynamics (MD) simulations of TIM-3 and -4 to understand how glycosylation affects structural features of these proteins. Finally, we use these models to investigate the functional relevance of glycosylation for TIM-3 function and ligand binding. Overall, we present a powerful workflow to better understand the detailed molecular structures and functions of the mucinome.


Assuntos
Receptor Celular 2 do Vírus da Hepatite A , Mucinas , Mucinas/metabolismo , Polissacarídeo-Liases , Polissacarídeos/química
6.
ACS Infect Dis ; 9(10): 1918-1931, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37728236

RESUMO

A collaborative, open-science team undertook discovery of novel small molecule inhibitors of the SARS-CoV-2 nsp16-nsp10 2'-O-methyltransferase using a high throughput screening approach with the potential to reveal new inhibition strategies. This screen yielded compound 5a, a ligand possessing an electron-deficient double bond, as an inhibitor of SARS-CoV-2 nsp16 activity. Surprisingly, X-ray crystal structures revealed that 5a covalently binds within a previously unrecognized cryptic pocket near the S-adenosylmethionine binding cleft in a manner that prevents occupation by S-adenosylmethionine. Using a multidisciplinary approach, we examined the mechanism of binding of compound 5a to the nsp16 cryptic pocket and developed 5a derivatives that inhibited nsp16 activity and murine hepatitis virus replication in rat lung epithelial cells but proved cytotoxic to cell lines canonically used to examine SARS-CoV-2 infection. Our study reveals the druggability of this newly discovered SARS-CoV-2 nsp16 cryptic pocket, provides novel tool compounds to explore the site, and suggests a new approach for discovery of nsp16 inhibition-based pan-coronavirus therapeutics through structure-guided drug design.


Assuntos
COVID-19 , SARS-CoV-2 , Camundongos , Ratos , Animais , SARS-CoV-2/metabolismo , S-Adenosilmetionina/química , S-Adenosilmetionina/metabolismo , Metiltransferases
7.
Sensors (Basel) ; 23(16)2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37631822

RESUMO

In the realm of the Internet of Things (IoT), a network of sensors and actuators collaborates to fulfill specific tasks. As the demand for IoT networks continues to rise, it becomes crucial to ensure the stability of this technology and adapt it for further expansion. Through an analysis of related works, including the feedback-based optimized fuzzy scheduling approach (FOFSA) algorithm, the adaptive task allocation technique (ATAT), and the osmosis load balancing algorithm (OLB), we identify their limitations in achieving optimal energy efficiency and fast decision making. To address these limitations, this research introduces a novel approach to enhance the processing time and energy efficiency of IoT networks. The proposed approach achieves this by efficiently allocating IoT data resources in the Mist layer during the early stages. We apply the approach to our proposed system known as the Mist-based fuzzy healthcare system (MFHS) that demonstrates promising potential to overcome the existing challenges and pave the way for the efficient industrial Internet of healthcare things (IIoHT) of the future.


Assuntos
Algoritmos , Conservação de Recursos Energéticos , Fenômenos Físicos , Indústrias , Tomada de Decisões
8.
ACS Omega ; 8(30): 27410-27418, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37546609

RESUMO

The search for new drugs against COVID-19 and its causative agent, SARS-CoV-2, is one of the major trends in the current medicinal chemistry. Targeting capping machinery could be one of the therapeutic concepts based on a unique mechanism of action. Viral RNA cap synthesis involves two methylation steps, the first of which is mediated by the nsp14 protein. Here, we rationally designed and synthesized a series of compounds capable of binding to both the S-adenosyl-l-methionine and the RNA-binding site of SARS-CoV-2 nsp14 N7-methyltransferase. These hybrid molecules showed excellent potency, high selectivity toward various human methyltransferases, nontoxicity, and high cell permeability. Despite the outstanding activity against the enzyme, our compounds showed poor antiviral performance in vitro. This suggests that the activity of this viral methyltransferase has no significant effect on virus transcription and replication at the cellular level. Therefore, our compounds represent unique tools to further explore the role of the SARS-CoV-2 nsp14 methyltransferase in the viral life cycle and the pathogenesis of COVID-19.

9.
Eur J Med Chem ; 260: 115713, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37597437

RESUMO

Protein arginine methyltransferases (PRMTs) catalyze the methylation of the terminal nitrogen atoms of the guanidino group of arginine of protein substrates. The aberrant expression of these methyltransferases is linked to various diseases, making them promising therapeutic targets. Currently, PRMT inhibitors are at different stages of clinical development, which validated their significance as drug targets. Structural Genomics Consortium (SGC) has reported several small fragment inhibitors as Class I PRMT inhibitors, which can be the starting point for rational drug development. Herein, we report the successful application of a fragment-based approach toward the discovery of selective Class I PRMT inhibitors. Structure-based ligand optimization was performed by strategic incorporation of fragment hits on the drug-like quinazoline core and subsequent fragment growth in the desired orientation towards identified hydrophobic shelf. A clear SAR was established, and the lead compounds 55 and 56 displayed potent inhibition of Class I PRMTs with IC50 values of 92 nM and 37 nM against PRMT4. We report the systematic development of potent Class I PRMT inhibitors with good potency and about 100-fold selectivity when tested against a panel of 31 human DNA, RNA, and protein lysine and arginine methyltransferases. These improved small molecules will provide new options for the development of novel potent and selective PRMT4 inhibitors.


Assuntos
Desenho de Fármacos , Proteína-Arginina N-Metiltransferases , Humanos , Desenvolvimento de Medicamentos , Arginina , Catálise
10.
J Med Chem ; 66(12): 7785-7803, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37294077

RESUMO

An under-explored target for SARS-CoV-2 is the S-adenosyl methionine (SAM)-dependent methyltransferase Nsp14, which methylates the N7-guanosine of viral RNA at the 5'-end, allowing the virus to evade host immune response. We sought new Nsp14 inhibitors with three large library docking strategies. First, up to 1.1 billion lead-like molecules were docked against the enzyme's SAM site, leading to three inhibitors with IC50 values from 6 to 50 µM. Second, docking a library of 16 million fragments revealed 9 new inhibitors with IC50 values from 12 to 341 µM. Third, docking a library of 25 million electrophiles to covalently modify Cys387 revealed 7 inhibitors with IC50 values from 3.5 to 39 µM. Overall, 32 inhibitors encompassing 11 chemotypes had IC50 values < 50 µM and 5 inhibitors in 4 chemotypes had IC50 values < 10 µM. These molecules are among the first non-SAM-like inhibitors of Nsp14, providing starting points for future optimization.


Assuntos
COVID-19 , Metiltransferases , Humanos , SARS-CoV-2/genética , Proteínas não Estruturais Virais/genética , RNA Viral/genética , Exorribonucleases
11.
J Pharm Biomed Anal ; 233: 115492, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37269578

RESUMO

Swellable Core Technology (SCT) tablets, a solid oral dosage formulation designed for the controlled release of Active Pharmaceutical Ingredient (API), are made up of two distinct layers; an active layer containing the active ingredient (10-30%wt) and up to 90%wt polyethylene oxide (PEO); and a sweller layer which contains up to 65%wt PEO. The objective of this study was to develop a process to remove PEO from analytical test solutions and optimize API recovery using physicochemical properties of the API. Quantitation of PEO was performed by liquid chromatography (LC) using an evaporative light scattering detector (ELSD). This was used to build an understanding of removal of PEO using solid-phase extraction and liquid-liquid extraction techniques. A workflow was proposed to allow efficient development of analytical methods for SCT tablets with optimized sample clean-up.


Assuntos
Polietilenoglicóis , Tecnologia , Polietilenoglicóis/química , Comprimidos/química
12.
Anesthesiol Clin ; 41(2): 395-470, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37245950

RESUMO

This article summarizes clinical expert recommendations and findings for the application of ultrasound-guided procedures in chronic pain management. Data on analgesic outcomes and adverse effects were collected and analyzed and are reported in this narrative review. Ultrasound guidance offers opportunities for the treatment of pain, with focus in this article on greater occipital nerve, trigeminal nerves, sphenopalatine ganglion, stellate ganglion, suprascapular nerve, median nerve, radial nerve, ulnar nerve, transverse abdominal plane block, quadratus lumborum, rectus sheath, anterior cutaneous abdominal nerves, pectoralis and serratus plane, erector spinae plane, illioinguinal/iliohypogastric/genitofemoral nerve, lateral femoral cutaneous nerve, genicular nerve, and foot and ankle nerves.


Assuntos
Dor Crônica , Humanos , Dor Crônica/terapia , Músculos Abdominais/diagnóstico por imagem , Músculos Abdominais/inervação , Ultrassonografia , Abdome , Ultrassonografia de Intervenção/métodos , Dor Pós-Operatória/tratamento farmacológico
13.
Reg Anesth Pain Med ; 48(6): 312-318, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37080584

RESUMO

Interventional pain management (IPM) options for refractory neuropathic pain (NP) have recently increased with availability of peripheral nerve stimulation (PNS) equipment and expertise. Given a lack of high-quality evidence and guidelines on this topic, we sought to understand the perception of physicians with expertise in treating NP regarding IPM and the role of PNS. We emailed a survey in March 2022 to international NP experts including pain medicine physicians, researchers, and leaders of 11 professional pain societies. No representatives from vendors of PNS systems were included in the design of the survey nor as respondents. Among 24 respondents (67% of those contacted), the distal common peroneal, tibial, and sural nerves were most frequently targeted (60%) with PNS. Persistent postsurgical pain of more than 3 months was the most common indication for PNS (84%). The aggregate NP treatment algorithm in order of median rank was non-opioid medications as first line, IPM including epidural/perineural steroid injections tied with transcutaneous electrical nerve stimulation as second line, pulsed radiofrequency (RF) tied with RF ablation/denervation as third line, temporary then permanent PNS as fourth line, followed by spinal cord stimulation, opioids, cryoablation, botulinum, peripheral nerve field stimulation, intrathecal targeted drug delivery, and others. Before offering PNS, 12 respondents (50%) indicated their preference for trialing non-neuromodulation treatments for 1-3 months. Twenty-two respondents (92%) agreed PNS should be offered early in the treatment of neuropathic pain. The most common barriers to PNS use were cost, lack of high-quality evidence in support of its use, lack of exposure to PNS in training programs, and lack of familiarity with the use of ultrasound guidance. PNS appears to have an increasing role in the treatment of NP but more research is needed on the outcomes of PNS to elucidate its role.


Assuntos
Dor Crônica , Neuralgia , Estimulação da Medula Espinal , Estimulação Elétrica Nervosa Transcutânea , Humanos , Neuralgia/diagnóstico , Neuralgia/terapia , Manejo da Dor , Nervos Periféricos , Dor Crônica/diagnóstico , Dor Crônica/terapia
14.
RSC Med Chem ; 14(3): 507-519, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36970153

RESUMO

A naturally inspired chemical library of 25 molecules was synthesised guided by 3-D dimensionality and natural product likeness factors to explore a new chemical space. The synthesised chemical library, consisting of fused-bridged dodecahydro-2a,6-epoxyazepino[3,4,5-c,d]indole skeletons, followed lead likeness factors in terms of molecular weight, C-sp3 fraction and Clog P. Screening of the 25 compounds against lung cells infected with SARS-CoV-2 led to the identification of 2 hits. Although the chemical library showed cytotoxicity, the two hits (3b, 9e) showed the highest antiviral activity (EC50 values of 3.7 and 1.4 µM, respectively) with an acceptable cytotoxicity difference. Computational analysis based on docking and molecular dynamics simulations against main protein targets in SARS-CoV-2 (main protease Mpro, nucleocapsid phosphoprotein, non-structural protein nsp10-nsp16 complex and RBD/ACE2 complex) were performed. The computational analysis proposed the possible binding targets to be either Mpro or the nsp10-nsp16 complex. Biological assays were performed to confirm this proposition. A cell-based assay for Mpro protease activity using a reverse-nanoluciferase (Rev-Nluc) reporter confirmed that 3b targets Mpro. These results open the way towards further hit-to-lead optimisations.

15.
J Am Chem Soc ; 145(13): 7268-7277, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36947559

RESUMO

Polyoxometalates (POMs) featuring 7, 12, 18, or more redox-accessible transition metal ions are ubiquitous as selective catalysts, especially for oxidation reactions. The corresponding synthetic and catalytic chemistry of stable, discrete, capping-ligand-free polythiometalates (PTMs), which could be especially attractive for reduction reactions, is much less well developed. Among the challenges are the propensity of PTMs to agglomerate and the tendency for agglomeration to block reactant access of catalyst active sites. Nevertheless, the pervasive presence of transition metal sulfur clusters metalloenzymes or cofactors that catalyze reduction reactions and the justifiable proliferation of studies of two-dimensional (2D) metal-chalcogenides as reduction catalysts point to the promise of well-defined and controllable PTMs as reduction catalysts. Here, we report the fabrication of agglomeration-immune, reactant-accessible, capping-ligand-free CoIIMo6IVS24n- clusters as periodic arrays in a water-stable, hierarchically porous Zr-metal-organic framework (MOF; NU1K) by first installing a disk-like Anderson polyoxometalate, CoIIIMo6VIO24m-, in size-matched micropores where the siting is established via difference electron density (DED) X-ray diffraction (XRD) experiments. Flowing H2S, while heating, reduces molybdenum(VI) ions to Mo(IV) and quantitatively replaces oxygen anions with sulfur anions (S2-, HS-, S22-). DED maps show that MOF-templated POM-to-PTM conversion leaves clusters individually isolated in open-channel-connected micropores. The structure of the immobilized cluster as determined, in part, by X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure (XAFS) analysis, and pair distribution function (PDF) analysis of total X-ray scattering agrees well with the theoretically simulated structure. PTM@MOF displays both electrocatalytic and photocatalytic competency for hydrogen evolution. Nevertheless, the initially installed PTM appears to be a precatalyst, gaining competency only after the loss of ∼3 to 6 sulfurs and exposure to hydride-forming metal ions.

16.
J Med Chem ; 66(7): 5041-5060, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-36948210

RESUMO

DCAF1 is a substrate receptor of two distinct E3 ligases (CRL4DCAF1 and EDVP), plays a critical physiological role in protein degradation, and is considered a drug target for various cancers. Antagonists of DCAF1 could be used toward the development of therapeutics for cancers and viral treatments. We used the WDR domain of DCAF1 to screen a 114-billion-compound DNA encoded library (DEL) and identified candidate compounds using similarity search and machine learning. This led to the discovery of a compound (Z1391232269) with an SPR KD of 11 µM. Structure-guided hit optimization led to the discovery of OICR-8268 (26e) with an SPR KD of 38 nM and cellular target engagement with EC50 of 10 µM as measured by cellular thermal shift assay (CETSA). OICR-8268 is an excellent tool compound to enable the development of next-generation DCAF1 ligands toward cancer therapeutics, further investigation of DCAF1 functions in cells, and the development of DCAF1-based PROTACs.


Assuntos
Neoplasias , Ubiquitina-Proteína Ligases , Humanos , Ligantes , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Transporte/química
17.
Biochim Biophys Acta Gen Subj ; 1867(4): 130319, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36764586

RESUMO

Seven coronaviruses have infected humans (HCoVs) to-date. SARS-CoV-2 caused the current COVID-19 pandemic with the well-known high mortality and severe socioeconomic consequences. MERS-CoV and SARS-CoV caused epidemic of MERS and SARS, respectively, with severe respiratory symptoms and significant fatality. However, HCoV-229E, HCoV-NL63, HCoV-HKU1, and HCoV-OC43 cause respiratory illnesses with less severe symptoms in most cases. All coronaviruses use RNA capping to evade the immune systems of humans. Two viral methyltransferases, nsp14 and nsp16, play key roles in RNA capping and are considered valuable targets for development of anti-coronavirus therapeutics. But little is known about the kinetics of nsp10-nsp16 methyltransferase activities of most HCoVs, and reliable assays for screening are not available. Here, we report the expression, purification, and kinetic characterization of nsp10-nsp16 complexes from six HCoVs in parallel with previously characterized SARS-CoV-2. Probing the active sites of all seven by SS148 and WZ16, the two recently reported dual nsp14 / nsp10-nsp16 inhibitors, revealed pan-inhibition. Overall, our study show feasibility of developing broad-spectrum dual nsp14 / nsp10-nsp16-inhibitor therapeutics.


Assuntos
COVID-19 , Humanos , Metiltransferases/química , Pandemias , RNA , SARS-CoV-2/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-36833654

RESUMO

The regulation of prescription drugs is an important health, safety, and equity issue. However, regulatory processes do not always consider evidence on sex, gender, and factors such as age and race, omissions that advocates have highlighted for several decades. Assessing the impact of sex-related factors is critical to ensuring drug safety and efficacy for females and males, and for informing clinical product monographs and consumer information. Gender-related factors affect prescribing, access to drugs, needs and desires for specific prescribed therapies. This article draws on a policy-research partnership project that examined the lifecycle management of prescription drugs in Canada using a sex and gender-based analysis plus (SGBA+) lens. In the same time period, Health Canada created a Scientific Advisory Committee on Health Products for Women, in part to examine drug regulation. We report on grey literature and selected regulatory documents to illustrate the extent to which sex and gender-based analysis plus (SGBA+) is utilized in regulation and policy. We identify omissions in the management of prescription drugs, and name opportunities for improvements by integrating SGBA+ into drug sponsor applications, clinical trials development, and pharmacovigilance. We report on recent efforts to incorporate sex disaggregated data and recommend ways that the management of prescription drugs can benefit from more integration of sex, gender, and equity.


Assuntos
Medicamentos sob Prescrição , Masculino , Humanos , Feminino , Fatores Sexuais , Comitês Consultivos , Prescrições , Canadá
19.
Biochim Biophys Acta Gene Regul Mech ; 1866(2): 194922, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36822575

RESUMO

Protein arginine methyltransferases (PRMTs) catalyze the transfer of methyl groups to specific arginine residues of histones and nonhistone proteins. There are nine members in the PRMT family (PRMT1 to PRMT9), and PRMT1 is a dominant member catalyzing majority of arginine methylation in the cell. However, none of the PRMTs is active with recombinant nucleosome as substrate in vitro. Here, we report the discovery of the first in class novel crosstalk between histone H4 lysine 20 (H4K20) monomethylation on nucleosome by SETD8 and histone H4 arginine 3 (H4R3) methylation by PRMT1 in vitro. Full kinetic characterization and mass spectrometry analysis indicated that PRMT1 is only active with recombinant nucleosomes monomethylated at H4K20 by SETD8. These data suggests that the level of activity of PRMT1 could potentially be regulated selectively by SETD8 in various pathways, providing a new approach for discovery of selective regulators of PRMT1 activity.


Assuntos
Histonas , Nucleossomos , Histonas/metabolismo , Metilação , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Arginina
20.
J Dent Educ ; 87(3): 401-407, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36377379

RESUMO

PURPOSE/OBJECTIVES: Online educational materials are growing in use, and dental students worldwide can benefit from higher quality and more accessible online supplemental resources. This study was created to evaluate the learning resources non-English speaking dental students desire and to pilot My Dental Key (MDK), an English, evidence-based, online dental educational platform. METHODS: Third to sixth year dental students at the Hue University of Medicine and Pharmacy were asked to pilot MDK over a 5-week period and were invited to answer three surveys throughout the study. A preliminary survey was given to gauge the participants' (n = 209) preferences regarding the use of English-based dental educational resources. Participants (n = 58) completed a presurvey prior to accessing MDK. After the 5-week period, participants (n = 38) were given a postsurvey to evaluate the platform's effectiveness as a supplemental educational resource. RESULTS: Overall, we found that: (1) students desire credible online supplemental resources in addition to current resources provided by their school, (2) the multimodal content that MDK provides is a strength that bridges language barriers (3) participants perceived that the content on MDK would help them in class and when treating patients. CONCLUSIONS: Improving the quality of online supplemental dental resources will have the capability to progress the current educational landscape, and further resources should be created to best serve the global dental community.


Assuntos
Educação a Distância , Estudantes de Odontologia , Humanos , Projetos Piloto , Inquéritos e Questionários , Percepção
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