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1.
J Neurophysiol ; 130(5): 1081-1091, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37728487

RESUMO

Normal and pathological locomotion can be discriminated by analyzing an animal's gait on a linear walkway. This step is labor intensive and introduces experimental bias due to the handling involved while placing and removing the animal between trials. We designed a system consisting of a runway embedded within a larger arena, which can be traversed ad libitum by unsupervised, freely moving mice, triggering the recording of short clips of locomotor activity. Multiple body parts were tracked using DeepLabCut and fed to an analysis pipeline (GaitGrapher) to extract gait metrics. We compared the results from unsupervised against the standard experimenter-supervised approach and found that gait parameters analyzed via the new approach were similar to a previously validated approach (Visual Gait Lab). These data show the utility of incorporating an unsupervised, automated, approach for collecting kinematic data for gait analysis.NEW & NOTEWORTHY The acquisition and analysis of walkway data is a time-consuming task. Here, we provide an unmonitored approach for collecting gait metrics that reduces the handling and stress of mice and saves time. A detailed pipeline is outlined that provides for the collection and analysis of data using an integrated suite of tools.


Assuntos
Marcha , Locomoção , Animais , Análise da Marcha , Fenômenos Biomecânicos
2.
Health Promot Pract ; 24(6): 1083-1086, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37877644

RESUMO

As an increasing number of Native Hawaiian and Pacific Islander adults move to the continental United States, the development and implementation of resources that promote access to cultural foods and support food sovereignty on the continent is crucial to perpetuate cultural practice and connection to the 'aina (land that feeds). Kalo (taro) is an important cultural food central to Native Hawaiian identity. Native Hawaiians connect their genealogy as far back to the cultivation of kalo and the creation of kalo itself. In this practice note, we describe the creation of a mala kalo (cultivated field for taro) in Oregon by the Ka'aha Lahui O 'Olekona Hawaiian Civic Club. An ongoing project over the past 3 years, the creation of a mala kalo exceeded expectations. Not only did the mala allow the cultivation of kalo outside of Hawaii, the mala became a place for the community to unite toward common goals of connecting with the land, promoting mental health, and creating a sense of place in their diaspora. This project indicates that not only is the creation of mala kalo in Oregon feasible, it may also be an important opportunity for the growing number of Native Hawaiians and Pacific Islanders adults living on the continent to improve health outcomes through connections with cultural foods and practices.


Assuntos
Agricultura , Colocasia , Cultura , Adulto , Humanos , Havaí , Saúde Mental , Havaiano Nativo ou Outro Ilhéu do Pacífico/psicologia , População das Ilhas do Pacífico , Estados Unidos , Oregon
3.
Exp Brain Res ; 238(5): 1293-1303, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32322928

RESUMO

Somatosensory afferent transmission strength is controlled by several presynaptic mechanisms that reduce transmitter release at the spinal cord level. We focused this investigation on the role of α-adrenoceptors in modulating sensory transmission in low-threshold myelinated afferents and in pathways mediating primary afferent depolarization (PAD) of neonatal mouse spinal cord. We hypothesized that the activation of α-adrenoceptors depresses low threshold-evoked synaptic transmission and inhibits pathways mediating PAD. Extracellular field potentials (EFPs) recorded in the deep dorsal horn assessed adrenergic modulation of population monosynaptic transmission, while dorsal root potentials (DRPs) recorded at root entry zone assessed adrenergic modulation of PAD. We found that noradrenaline (NA) and the α1-adrenoceptor agonists phenylephrine and cirazoline depressed synaptic transmission (by 15, 14 and 22%, respectively). DRPs were also depressed by NA, phenylephrine and cirazoline (by 62, 30, and 64%, respectively), and by the α2-adrenoceptor agonist clonidine, although to a lower extent (20%). We conclude that NA depresses monosynaptic transmission of myelinated afferents onto deep dorsal horn neurons via α1-adrenoceptors and inhibits interneuronal pathways mediating PAD through the activation of α1- and α2-adrenoceptors. The functional significance of these modulatory actions in shaping cutaneous and muscle sensory information during motor behaviors requires further study.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Fenômenos Eletrofisiológicos/fisiologia , Fibras Nervosas Mielinizadas/fisiologia , Neurônios Aferentes/fisiologia , Receptores Adrenérgicos alfa 1/fisiologia , Receptores Adrenérgicos alfa 2/fisiologia , Corno Dorsal da Medula Espinal/fisiologia , Transmissão Sináptica/fisiologia , Animais , Animais Recém-Nascidos , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos BALB C , Vias Neurais/fisiologia , Receptores Adrenérgicos alfa 1/efeitos dos fármacos , Receptores Adrenérgicos alfa 2/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos
4.
Nucleic Acids Res ; 44(3): 1256-70, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26740583

RESUMO

Toxin-antitoxin (TA) systems play key roles in bacterial persistence, biofilm formation and stress responses. The MazF toxin from the Escherichia coli mazEF TA system is a sequence- and single-strand-specific endoribonuclease, and many studies have led to the proposal that MazF family members exclusively target mRNA. However, recent data indicate some MazF toxins can cleave specific sites within rRNA in concert with mRNA. In this report, we identified the repertoire of RNAs cleaved by Mycobacterium tuberculosis toxin MazF-mt9 using an RNA-seq-based approach. This analysis revealed that two tRNAs were the principal targets of MazF-mt9, and each was cleaved at a single site in either the tRNA(Pro14) D-loop or within the tRNA(Lys43) anticodon. This highly selective target discrimination occurs through recognition of not only sequence but also structural determinants. Thus, MazF-mt9 represents the only MazF family member known to target tRNA and to require RNA structure for recognition and cleavage. Interestingly, the tRNase activity of MazF-mt9 mirrors basic features of eukaryotic tRNases that also generate stable tRNA-derived fragments that can inhibit translation in response to stress. Our data also suggest a role for tRNA distinct from its canonical adapter function in translation, as cleavage of tRNAs by MazF-mt9 downregulates bacterial growth.


Assuntos
Proteínas de Bactérias/metabolismo , Endorribonucleases/metabolismo , Mycobacterium tuberculosis/metabolismo , RNA de Transferência/metabolismo , Anticódon/genética , Anticódon/metabolismo , Proteínas de Bactérias/genética , Sequência de Bases , Sítios de Ligação/genética , Northern Blotting , Endorribonucleases/genética , Modelos Moleculares , Mycobacterium tuberculosis/genética , Conformação de Ácido Nucleico , Ligação Proteica , RNA Bacteriano/química , RNA Bacteriano/genética , RNA Bacteriano/metabolismo , RNA de Transferência/química , RNA de Transferência/genética
5.
J Biol Chem ; 289(11): 7788-98, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24448800

RESUMO

The Doc toxin from bacteriophage P1 (of the phd-doc toxin-antitoxin system) has served as a model for the family of Doc toxins, many of which are harbored in the genomes of pathogens. We have shown previously that the mode of action of this toxin is distinct from the majority derived from toxin-antitoxin systems: it does not cleave RNA; in fact P1 Doc expression leads to mRNA stabilization. However, the molecular triggers that lead to translation arrest are not understood. The presence of a Fic domain, albeit slightly altered in length and at the catalytic site, provided a clue to the mechanism of P1 Doc action, as most proteins with this conserved domain inactivate GTPases through addition of an adenylyl group (also referred to as AMPylation). We demonstrated that P1 Doc added a single phosphate group to the essential translation elongation factor and GTPase, elongation factor (EF)-Tu. The phosphorylation site was at a highly conserved threonine, Thr-382, which was blocked when EF-Tu was treated with the antibiotic kirromycin. Therefore, we have established that Fic domain proteins can function as kinases. This distinct enzymatic activity exhibited by P1 Doc also solves the mystery of the degenerate Fic motif unique to the Doc family of toxins. Moreover, we have established that all characterized Fic domain proteins, even those that phosphorylate, target pivotal GTPases for inactivation through a post-translational modification at a single functionally critical acceptor site.


Assuntos
Bacteriófago P1/metabolismo , Proteínas de Escherichia coli/metabolismo , Elongação Traducional da Cadeia Peptídica , Fator Tu de Elongação de Peptídeos/metabolismo , Proteínas Virais/metabolismo , Motivos de Aminoácidos , Antibacterianos/química , Sítios de Ligação , Proliferação de Células , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Espectrometria de Massas , Simulação de Acoplamento Molecular , Fosforilação , Ligação Proteica , Processamento de Proteína Pós-Traducional , Estrutura Terciária de Proteína , Piridonas/química , RNA Mensageiro/metabolismo , Proteínas Recombinantes/química , Treonina/química
6.
Bioorg Med Chem Lett ; 25(17): 3488-94, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26212776

RESUMO

Synthesis and SAR studies of novel triazolobenzazepinones as gamma secretase modulators (GSMs) are presented in this communication. Starting from our azepinone leads, optimization studies toward improving central lowering of Aß42 led to the discovery of novel benzo-fused azepinones. Several benzazepinones were profiled in vivo and found to lower brain Aß42 levels in Sprague Dawley rats and transgenic APP-YAC mice in a dose-dependent manner after a single oral dose. Compound 34 was further progressed into a pilot study in our cisterna-magna-ported rhesus monkey model, where we observed robust lowering of CSF Aß42 levels.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Descoberta de Drogas , Macaca mulatta , Camundongos , Camundongos Transgênicos , Ratos , Ratos Sprague-Dawley
7.
J Biol Chem ; 287(16): 12835-47, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22354968

RESUMO

The Mycobacterium tuberculosis genome harbors an unusually large number of toxin-antitoxin (TA) modules. Curiously, over half of these are VapBC (virulence-associated protein) family members. Nonetheless, the cellular target, precise mode of action, and physiological role of the VapC toxins in this important pathogen remain unclear. To better understand the function of this toxin family, we studied the features and biochemical properties of a prototype M. tuberculosis VapBC TA system, vapBC-mt4 (Rv0596c-Rv0595c). VapC-mt4 expression resulted in growth arrest, a hallmark of all TA toxins, in Escherichia coli, Mycobacterium smegmatis, and M. tuberculosis. Its expression led to translation inhibition accompanied by a gradual decrease in the steady-state levels of several mRNAs. VapC-mt4 exhibited sequence-specific endoribonuclease activity on mRNA templates at ACGC and AC(A/U)GC sequences. However, the cleavage activity of VapC-mt4 was comparatively weak relative to the TA toxin MazF-mt1 (Rv2801c). Unlike other TA toxins, translation inhibition and growth arrest preceded mRNA cleavage, suggesting that the RNA binding property of VapC-mt4, not RNA cleavage, initiates toxicity. In support of this hypothesis, expression of VapC-mt4 led to an increase in the recovery of total RNA with time in contrast to TA toxins that inhibit translation via direct mRNA cleavage. Additionally, VapC-mt4 exhibited stable, sequence-specific RNA binding in an electrophoretic mobility shift assay. Finally, VapC-mt4 inhibited protein synthesis in a cell-free system without cleaving the corresponding mRNA. Therefore, the activity of VapC-mt4 is mechanistically distinct from other TA toxins because it appears to primarily inhibit translation through selective, stable binding to RNA.


Assuntos
Antitoxinas/metabolismo , Toxinas Bacterianas/metabolismo , Mycobacterium tuberculosis , Biossíntese de Proteínas/fisiologia , RNA Bacteriano/metabolismo , Proteínas de Ligação a RNA/metabolismo , Antitoxinas/genética , Toxinas Bacterianas/genética , DNA Bacteriano/metabolismo , Escherichia coli/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Ribossomos/genética , Ribossomos/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
8.
Cureus ; 15(9): e44922, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37814752

RESUMO

Pulsed radiofrequency is a well-documented treatment option for multiple painful conditions where pulses of energy are delivered close to neural elements. Since its earliest adoption, this technique has gained increasing acceptance as a minimally invasive procedure, and new applications are evolving. Studies have shown microscopic and biochemical changes that reflect beneficial effects; however, the exact mechanism of action is not yet completely understood. To redress this paucity, 11,476 articles of scientific relevance published between 1980 and November 2022 were mined through a search of the PubMed database, arriving at 49 studies both in animals and humans. In general, the experimental studies examined have shown that pulsed radiofrequency induces multiple changes with antinociceptive and neuromodulatory effects. These modifications include changes in neural and glial cells, synaptic transmission, and perineural space. Studies also reveal that pulsed radiofrequency regulates inflammatory responses, cellular signaling proteins, and the expression of genes related to pain transmission, acting in biological processes in structures such as myelin, mitochondria, axons, glial cells, connective tissue, regulation of proteins, ion channels, and neurotransmitters.

9.
J Biol Chem ; 286(17): 14770-8, 2011 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-21324908

RESUMO

The enzymatic activity of the RelE bacterial toxin component of the Escherichia coli RelBE toxin-antitoxin system has been extensively studied in vitro and to a lesser extent in vivo. These earlier reports revealed that 1) RelE alone does not exhibit mRNA cleavage activity, 2) RelE mediates mRNA cleavage through its association with the ribosome, 3) RelE-mediated mRNA cleavage occurs at the ribosomal A site and, 4) Cleavage of mRNA by RelE exhibits high codon specificity. More specifically, RelE exhibits a preference for the stop codons UAG and UGA and sense codons CAG and UCG in vitro. In this study, we used a comprehensive primer extension approach to map the frequency and codon specificity of RelE cleavage activity in vivo. We found extensive cleavage at the beginning of the coding region of five transcripts, ompA, lpp, ompF, rpsA, and tufA. We then mapped RelE cleavage sites across one short transcript (lpp) and two long transcripts (ompF and ompA). RelE cut all of these transcripts frequently and efficiently within the first ∼100 codons, only occasionally cut beyond this point, and rarely cut at sites in proximity to the 3' end. Among 196 RelE sites in these five transcripts, there was no preference for CAG or UCG sense codons. In fact, bioinformatic analysis of the RelE cleavage sites failed to identify any sequence preferences. These results suggest a model of RelE function distinct from those proposed previously, because RelE directed frequent codon-independent mRNA cleavage coincident with the commencement of translation elongation.


Assuntos
Toxinas Bacterianas/metabolismo , Códon/metabolismo , RNA Mensageiro/metabolismo , Região 5'-Flanqueadora , Sítios de Ligação , Proteínas de Escherichia coli , Hidrólise , Biossíntese de Proteínas
10.
Sci Rep ; 12(1): 5588, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379831

RESUMO

Battery electric vehicles (BEVs) have emerged as a promising alternative to traditional internal combustion engine (ICE) vehicles due to benefits in improved fuel economy, lower operating cost, and reduced emission. BEVs use electric motors rather than fossil fuels for propulsion and typically store electric energy in lithium-ion cells. With rising concerns over fossil fuel depletion and the impact of ICE vehicles on the climate, electric mobility is widely considered as the future of sustainable transportation. BEVs promise to drastically reduce greenhouse gas emissions as a result of the transportation sector. However, mass adoption of BEVs faces major barriers due to consumer worries over several important battery-related issues, such as limited range, long charging time, lack of charging stations, and high initial cost. Existing solutions to overcome these barriers, such as building more charging stations, increasing battery capacity, and stationary vehicle-to-vehicle (V2V) charging, often suffer from prohibitive investment costs, incompatibility to existing BEVs, or long travel delays. In this paper, we propose Peer-to-Peer Car Charging (P2C2), a scalable approach for charging BEVs that alleviates the need for elaborate charging infrastructure. The central idea is to enable BEVs to share charge among each other while in motion through coordination with a cloud-based control system. To re-vitalize a BEV fleet, which is continuously in motion, we introduce Mobile Charging Stations (MoCS), which are high-battery-capacity vehicles used to replenish the overall charge in a vehicle network. Unlike existing V2V charging solutions, the charge sharing in P2C2 takes place while the BEVs are in-motion, which aims at minimizing travel time loss. To reduce BEV-to-BEV contact time without increasing manufacturing costs, we propose to use multiple batteries of varying sizes and charge transfer rates. The faster but smaller batteries are used for charge transfer between vehicles, while the slower but larger ones are used for prolonged charge storage. We have designed the overall P2C2 framework and formalized the decision-making process of the cloud-based control system. We have evaluated the effectiveness of P2C2 using a well-characterized simulation platform and observed dramatic improvement in BEV mobility. Additionally, through statistical analysis, we show that a significant reduction in carbon emission is also possible if MoCS can be powered by renewable energy sources.

12.
Bioorg Med Chem Lett ; 21(13): 4083-7, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21616665

RESUMO

Synthesis, SAR, and evaluation of aryl triazoles as novel gamma secretase modulators (GSMs) are presented in this communication. Starting from the literature and in-house leads, we evaluated a range of five-membered heterocycles as replacements for olefins commonly found in non-acid GSMs. 1,2,3-C-aryl-triazoles were identified as suitable replacements which exhibited good modulation of γ-secretase activity, excellent pharmacokinetics and good central lowering of Aß42 in Sprague-Dawley rats.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Triazóis/síntese química , Triazóis/farmacologia , Peptídeos beta-Amiloides/metabolismo , Animais , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Concentração Inibidora 50 , Estrutura Molecular , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Triazóis/metabolismo
13.
Int J Radiat Oncol Biol Phys ; 111(4): 856-864, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34058256

RESUMO

PURPOSE: Delivering linguistically competent care is critical to serving patients who have limited English proficiency (LEP) and represents a key national strategy to help reduce health disparities. Current acceptable standards of communication with patients who have LEP include providers communicating through professional interpretive services or bilingual providers speaking the patients' preferred language directly. This randomized clinical trial tests the effect of patient-provider language concordance on patient satisfaction. METHODS AND MATERIALS: Eighty-three adult Spanish-speaking patients with cancer were randomly assigned to receive care from either (1) 1 of 2 bilingual physicians speaking to the patient directly in Spanish or (2) the same physicians speaking English and using a professional interpreter service. Validated questionnaires were administered to assess patient-reported satisfaction with both provider communication and overall care. Transcripts of initial consultations were analyzed for content variations. RESULTS: Compared with patients receiving care through professional interpretive services, patients cared for in direct Spanish reported significantly improved general satisfaction, technical quality of care (mean composite score [MCS], 4.41 vs 4.06; P = .005), care team interpersonal manner (MCS, 4.37 vs 3.88; P = .004), communication (MCS, 4.50 vs 4.25; P = .018), and time spent with patient,(MCS, 4.30 vs 3.92; P = .028). Specific to physician communication, patients rated direct-Spanish care more highly in perceived opportunity to disclose concerns (MCS 4.91 vs 4.62; P = .001), physician empathy (MCS, 4.94 vs 4.59; P <.001), confidence in physician abilities (MCS, 4.84 vs 4.51; P = .001), and general satisfaction with their physician (MCS, 4.88 vs 4.59; P <.001). Analyzing the content of consultation encounters revealed differences between study arms, with the direct-Spanish arm having more physician speech related to patient history verification (mean number of utterances, 13 vs 9; P = .01) and partnering activities (mean utterances, 16 vs 5; P <.001). Additionally, patients in the direct-Spanish arm were more likely to initiate unprompted speech (mean utterances, 11 vs 3; P <.001) and asked their providers more questions (mean utterances, 11 vs 4; P = .007). CONCLUSIONS: This study shows improved patient-reported satisfaction among patients with cancer who had LEP and were cared for in direct Spanish compared with interpreter-based communication. Further research into interventions to mitigate the patient-provider language barrier is necessary to optimize care for this population.


Assuntos
Idioma , Neoplasias , Adulto , Barreiras de Comunicação , Hispânico ou Latino , Humanos , Neoplasias/terapia , Satisfação do Paciente , Relações Médico-Paciente
14.
Front Cell Neurosci ; 15: 715427, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35185470

RESUMO

Developing spinal motor networks produce a diverse array of outputs, including episodic and continuous patterns of rhythmic activity. Variation in excitability state and neuromodulatory tone can facilitate transitions between episodic and continuous rhythms; however, the intrinsic mechanisms that govern these rhythms and their transitions are poorly understood. Here, we tested the capacity of a single central pattern generator (CPG) circuit with tunable properties to generate multiple outputs. To address this, we deployed a computational model composed of an inhibitory half-center oscillator (HCO). Following predictions of our computational model, we tested the contributions of key properties to the generation of an episodic rhythm produced by isolated spinal cords of the newborn mouse. The model recapitulates the diverse state-dependent rhythms evoked by dopamine. In the model, episodic bursting depended predominantly on the endogenous oscillatory properties of neurons, with Na+/K+ ATPase pump (I Pump) and hyperpolarization-activated currents (I h ) playing key roles. Modulation of either I Pump or I h produced transitions between episodic and continuous rhythms and silence. As maximal activity of I Pump decreased, the interepisode interval and period increased along with a reduction in episode duration. Decreasing maximal conductance of I h decreased episode duration and increased interepisode interval. Pharmacological manipulations of I h with ivabradine, and I Pump with ouabain or monensin in isolated spinal cords produced findings consistent with the model. Our modeling and experimental results highlight key roles of I h and I Pump in producing episodic rhythms and provide insight into mechanisms that permit a single CPG to produce multiple patterns of rhythmicity.

15.
Bioorg Med Chem Lett ; 20(2): 755-8, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20005099

RESUMO

We report herein a novel series of difluoropiperidine acetic acids as modulators of gamma-secretase. Synthesis of 2-aryl-3,3-difluoropiperidine analogs was facilitated by a unique and selective beta-difluorination with Selectfluor. Compounds 1f and 2c were selected for in vivo assessment and demonstrated selective lowering of Abeta42 in a genetically engineered mouse model of APP processing. Moreover, in a 7-day safety study, rats treated orally with compound 1f (250mg/kg per day, AUC(0-24)=2100microMh) did not exhibit Notch-related effects.


Assuntos
Acetatos/química , Secretases da Proteína Precursora do Amiloide/metabolismo , Flúor/química , Piperidinas/química , Acetatos/síntese química , Acetatos/farmacocinética , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Compostos de Diazônio/química , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Piperidinas/síntese química , Piperidinas/farmacocinética , Ratos , Receptores Notch/metabolismo
16.
Bioorg Med Chem Lett ; 20(7): 2279-82, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20207146

RESUMO

The development of a novel series of purines as gamma-secretase modulators for potential use in the treatment of Alzheimer's disease is disclosed herein. Optimization of a previously disclosed pyrimidine series afforded a series of potent purine-based gamma-secretase modulators with 300- to 2000-fold in vitro selectivity over inhibition of Notch cleavage and that selectively reduces Alphabeta42 in an APP-YAC transgenic mouse model.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/antagonistas & inibidores , Fragmentos de Peptídeos/antagonistas & inibidores , Purinas/química , Purinas/uso terapêutico , Secretases da Proteína Precursora do Amiloide/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Humanos , Camundongos , Camundongos Transgênicos , Fragmentos de Peptídeos/metabolismo , Purinas/farmacologia , Receptores Notch/metabolismo , Relação Estrutura-Atividade
17.
Neurosci Lett ; 736: 135257, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32682848

RESUMO

Somatosensory information can be modulated at the spinal cord level by primary afferent depolarization (PAD), known to produce presynaptic inhibition (PSI) by decreasing neurotransmitter release through the activation of presynaptic ionotropic receptors. Descending monoaminergic systems also modulate somatosensory processing. We investigated the role of D1-like and D2-like receptors on pathways mediating PAD in the hemisected spinal cord of neonatal mice. We recorded low-threshold evoked dorsal root potentials (DRPs) and population monosynaptic responses as extracellular field potentials (EFPs). We used a paired-pulse conditioning-test protocol to assess homosynaptic and heterosynaptic depression of evoked EFPs to discriminate between dopaminergic effects on afferent synaptic efficacy and/or on pathways mediating PAD, respectively. DA (10 µM) depressed low-threshold evoked DRPs by 43 %, with no effect on EFPs. These depressant effects on DRPs were mimicked by the D2-like receptor agonist quinpirole (35 %). Moreover, by using selective antagonists at D2-like receptors (encompassing the D2, D3, and D4 subtypes), we found that the D2 and D3 receptor subtypes participate in the quinpirole depressant inhibitory effects of pathways mediating PAD.


Assuntos
Inibição Neural/fisiologia , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3/metabolismo , Medula Espinal/metabolismo , Transmissão Sináptica/fisiologia , Animais , Potenciais Pós-Sinápticos Excitadores , Camundongos , Vias Neurais/metabolismo , Neurônios Aferentes/metabolismo , Receptores Pré-Sinápticos/metabolismo
18.
Science ; 369(6506): 1010-1014, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32540901

RESUMO

Neutralizing antibodies have become an important tool in treating infectious diseases. Recently, two separate approaches yielded successful antibody treatments for Ebola-one from genetically humanized mice and the other from a human survivor. Here, we describe parallel efforts using both humanized mice and convalescent patients to generate antibodies against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein, which yielded a large collection of fully human antibodies that were characterized for binding, neutralization, and three-dimensional structure. On the basis of these criteria, we selected pairs of highly potent individual antibodies that simultaneously bind the receptor binding domain of the spike protein, thereby providing ideal partners for a therapeutic antibody cocktail that aims to decrease the potential for virus escape mutants that might arise in response to selective pressure from a single-antibody treatment.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adolescente , Adulto , Enzima de Conversão de Angiotensina 2 , Animais , Anticorpos Neutralizantes/química , Anticorpos Antivirais/química , Afinidade de Anticorpos , Citotoxicidade Celular Dependente de Anticorpos , Betacoronavirus/química , Sítios de Ligação de Anticorpos , Anticorpos Amplamente Neutralizantes/química , Anticorpos Amplamente Neutralizantes/imunologia , COVID-19 , Linhagem Celular , Infecções por Coronavirus/terapia , Citofagocitose , Epitopos , Humanos , Imunização Passiva , Camundongos , Pessoa de Meia-Idade , Modelos Moleculares , Testes de Neutralização , Pandemias , Peptidil Dipeptidase A/metabolismo , Domínios e Motivos de Interação entre Proteínas , Receptores de Coronavírus , Receptores Virais/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Adulto Jovem , Soroterapia para COVID-19
19.
Bioorg Med Chem Lett ; 19(11): 3081-4, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19410459

RESUMO

Histone deacetylase (HDAC) inhibition causes hyperacetylation of histones leading to differentiation, growth arrest and apoptosis of malignant cells, representing a new strategy in cancer therapy. Many of the known HDAC inhibitors (HDACi) that are in clinical trials possess a hydroxamic acid, that is a strong Zn(2+) binding group, thereby inhibiting some of the class I and class II isoforms. Herein we describe the identification of a selective class I HDAC inhibitor bearing a primary carboxamide moiety as zinc binding group. This HDACi displays good antiproliferative activity against multiple cancer cell lines, and demonstrates efficacy in a xenograft model comparable to vorinostat.


Assuntos
Amidas/química , Antineoplásicos/química , Inibidores Enzimáticos/química , Inibidores de Histona Desacetilases , Zinco/química , Amidas/síntese química , Amidas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Camundongos , Camundongos Nus , Relação Estrutura-Atividade , Vorinostat , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Bioorg Med Chem Lett ; 19(4): 1168-72, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19138845

RESUMO

The successful application of both solid and solution phase library synthesis, combined with tight integration into the medicinal chemistry effort, resulted in the efficient optimization of a novel structural series of selective HDAC1/HDAC2 inhibitors by the MRL-Boston Parallel Medicinal Chemistry group. An initial lead from a small parallel library was found to be potent and selective in biochemical assays. Advanced compounds were the culmination of iterative library design and possess excellent biochemical and cellular potency, as well as acceptable PK and efficacy in animal models.


Assuntos
Inibidores de Histona Desacetilases , Animais , Técnicas de Química Combinatória , Cães , Desenho de Fármacos , Histona Desacetilase 1 , Histona Desacetilase 2 , Humanos , Estrutura Molecular , Ratos , Proteínas Repressoras/antagonistas & inibidores , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
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