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1.
RNA ; 29(12): 1960-1972, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37793791

RESUMO

Cell-free protein synthesis (CFPS) systems enable easy in vitro expression of proteins with many scientific, industrial, and therapeutic applications. Here we present an optimized, highly efficient human cell-free translation system that bypasses many limitations of currently used in vitro systems. This CFPS system is based on extracts from human HEK293T cells engineered to endogenously express GADD34 and K3L proteins, which suppress phosphorylation of translation initiation factor eIF2α. Overexpression of GADD34 and K3L proteins in human cells before cell lysate preparation significantly simplifies lysate preparation. We find that expression of the GADD34 and K3L accessory proteins before cell lysis maintains low levels of phosphorylation of eIF2α in the extracts. During in vitro translation reactions, eIF2α phosphorylation increases moderately in a GCN2-dependent fashion that can be inhibited by GCN2 kinase inhibitors. This new CFPS system should be useful for exploring human translation mechanisms in more physiological conditions outside the cell.


Assuntos
Fator de Iniciação 2 em Eucariotos , Proteínas , Humanos , Células HEK293 , Fosforilação , Proteínas/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Biossíntese de Proteínas , Sistema Livre de Células/metabolismo
2.
Anesthesiology ; 127(4): 633-644, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28727581

RESUMO

BACKGROUND: Postoperative pain and opioid use are associated with postoperative delirium. We designed a single-center, randomized, placebo-controlled, parallel-arm, double-blinded trial to determine whether perioperative administration of gabapentin reduced postoperative delirium after noncardiac surgery. METHODS: Patients were randomly assigned to receive placebo (N = 347) or gabapentin 900 mg (N = 350) administered preoperatively and for the first 3 postoperative days. The primary outcome was postoperative delirium as measured by the Confusion Assessment Method. Secondary outcomes were postoperative pain, opioid use, and length of hospital stay. RESULTS: Data for 697 patients were included, with a mean ± SD age of 72 ± 6 yr. The overall incidence of postoperative delirium in any of the first 3 days was 22.4% (24.0% in the gabapentin and 20.8% in the placebo groups; the difference was 3.20%; 95% CI, 3.22% to 9.72%; P = 0.30). The incidence of delirium did not differ between the two groups when stratified by surgery type, anesthesia type, or preoperative risk status. Gabapentin was shown to be opioid sparing, with lower doses for the intervention group versus the control group. For example, the morphine equivalents for the gabapentin-treated group, median 6.7 mg (25th, 75th quartiles: 1.3, 20.0 mg), versus control group, median 6.7 mg (25th, 75th quartiles: 2.7, 24.8 mg), differed on the first postoperative day (P = 0.04). CONCLUSIONS: Although postoperative opioid use was reduced, perioperative administration of gabapentin did not result in a reduction of postoperative delirium or hospital length of stay.


Assuntos
Aminas/uso terapêutico , Analgésicos/uso terapêutico , Ácidos Cicloexanocarboxílicos/uso terapêutico , Delírio/prevenção & controle , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/prevenção & controle , Ácido gama-Aminobutírico/uso terapêutico , Idoso , Analgésicos Opioides/administração & dosagem , Método Duplo-Cego , Feminino , Gabapentina , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino
4.
bioRxiv ; 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36798401

RESUMO

Cell-free protein synthesis (CFPS) systems enable easy in vitro expression of proteins with many scientific, industrial, and therapeutic applications. Here we present an optimized, highly efficient human cell-free translation system that bypasses many limitations of currently used in vitro systems. This CFPS system is based on extracts from human HEK293T cells engineered to endogenously express GADD34 and K3L proteins, which suppress phosphorylation of translation initiation factor eIF2α. Overexpression of GADD34 and K3L proteins in human cells significantly simplifies cell lysate preparation. The new CFPS system improves the translation of 5' cap-dependent mRNAs as well as those that use internal ribosome entry site (IRES) mediated translation initiation. We find that expression of the GADD34 and K3L accessory proteins before cell lysis maintains low levels of phosphorylation of eIF2α in the extracts. During in vitro translation reactions, eIF2α phosphorylation increases moderately in a GCN2-dependent fashion that can be inhibited by GCN2 kinase inhibitors. We also find evidence for activation of regulatory pathways related to eukaryotic elongation factor 2 (eEF2) phosphorylation and ribosome quality control in the extracts. This new CFPS system should be useful for exploring human translation mechanisms in more physiological conditions outside the cell.

5.
J Am Heart Assoc ; 12(5): e027556, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36802928

RESUMO

Background The lifetime journey of patients with single-ventricle congenital heart disease is characterized by long-term challenges that are incompletely understood and still unfolding. Health care redesign requires a thorough understanding of this journey to create and implement solutions that improve outcomes. This study maps the lifetime journey of individuals with single-ventricle congenital heart disease and their families, identifies the most meaningful outcomes to them, and defines significant challenges in the journey. Methods and Results This qualitative research study involved experience group sessions and 1:1 interviews of patients, parents, siblings, partners, and stakeholders. Journey maps were created. The most meaningful outcomes to patients and parents and significant gaps in care were identified across the life journey. A total of 142 participants from 79 families and 28 stakeholders were included. Lifelong and life-stage specific journey maps were created. The most meaningful outcomes to patients and parents were identified and categorized using a "capability (doing the things in life you want to), comfort (experience of physical/emotional pain/distress), and calm (experiencing health care with the least impact on daily life)" framework. Gaps in care were identified and classified into areas of ineffective communication, lack of seamless transitions, lack of comprehensive support, structural deficiencies, and insufficient education. Conclusions There are significant gaps in care during the lifelong journey of individuals with single-ventricle congenital heart disease and their families. A thorough understanding of this journey is a critical first step in developing initiatives to redesign care around their needs and priorities. This approach can be used for people with other forms of congenital heart disease and other chronic conditions. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04613934.


Assuntos
Cardiopatias Congênitas , Coração Univentricular , Humanos , Pais/psicologia , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/terapia , Dor , Comunicação
6.
Nat Commun ; 11(1): 4941, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009412

RESUMO

Methods to directly inhibit gene expression using small molecules hold promise for the development of new therapeutics targeting proteins that have evaded previous attempts at drug discovery. Among these, small molecules including the drug-like compound PF-06446846 (PF846) selectively inhibit the synthesis of specific proteins, by stalling translation elongation. These molecules also inhibit translation termination by an unknown mechanism. Using cryo-electron microscopy (cryo-EM) and biochemical approaches, we show that PF846 inhibits translation termination by arresting the nascent chain (NC) in the ribosome exit tunnel. The arrested NC adopts a compact α-helical conformation that induces 28 S rRNA nucleotide rearrangements that suppress the peptidyl transferase center (PTC) catalytic activity stimulated by eukaryotic release factor 1 (eRF1). These data support a mechanism of action for a small molecule targeting translation that suppresses peptidyl-tRNA hydrolysis promoted by eRF1, revealing principles of eukaryotic translation termination and laying the foundation for new therapeutic strategies.


Assuntos
Terminação Traducional da Cadeia Peptídica , Preparações Farmacêuticas/metabolismo , Linhagem Celular , Humanos , Modelos Moleculares , Mutação/genética , Conformação Proteica , RNA Ribossômico/metabolismo , Ribossomos/metabolismo , Ribossomos/ultraestrutura
7.
Nat Struct Mol Biol ; 26(6): 501-509, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160784

RESUMO

The drug-like molecule PF-06446846 (PF846) binds the human ribosome and selectively blocks the translation of a small number of proteins by an unknown mechanism. In structures of PF846-stalled human ribosome nascent chain complexes, PF846 binds in the ribosome exit tunnel in a eukaryotic-specific pocket formed by 28S ribosomal RNA, and alters the path of the nascent polypeptide chain. PF846 arrests the translating ribosome in the rotated state of translocation, in which the peptidyl-transfer RNA 3'-CCA end is improperly docked in the peptidyl transferase center. Selections of messenger RNAs from mRNA libraries using translation extracts reveal that PF846 can stall translation elongation, arrest termination or even enhance translation, depending on nascent chain sequence context. These results illuminate how a small molecule selectively targets translation by the human ribosome, and provides a foundation for developing small molecules that modulate the production of proteins of therapeutic interest.


Assuntos
Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , Ribossomos/efeitos dos fármacos , Células HeLa , Compostos Heterocíclicos de 4 ou mais Anéis/química , Humanos , Modelos Moleculares , RNA Mensageiro/metabolismo , RNA de Transferência/metabolismo , Ribossomos/metabolismo
8.
J Med Econ ; 17(7): 508-19, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24720805

RESUMO

OBJECTIVE: Around one-third of patients with bipolar I disorder (BD-I) experience mixed episodes, characterized by both mania and depression, which tend to be more difficult and costly to treat. Atypical antipsychotics are recommended for the treatment of mixed episodes, although evidence of their efficacy, tolerability, and cost in these patients is limited. This study evaluates, from a UK National Health Service perspective, the cost-effectiveness of asenapine vs olanzapine in BD-I patients with mixed episodes. METHODS: Cost-effectiveness was assessed using a Markov model. Efficacy was informed by a post-hoc analysis of two short-term clinical trials, with response measured as a composite Young Mania Rating Score and Montgomery-Åsberg Depression Rating Scale end-point. Probabilities of discontinuation and relapse to manic, mixed, and depressive episodes were sourced from published meta-analyses. Direct costs (2012-2013 values) included drug acquisition, monitoring, and resource use related to bipolar disorder as well as selected adverse events. Benefits were measured as quality-adjusted life years (QALYs). RESULTS: For treating mixed episodes, asenapine generated 0.0187 more QALYs for an additional cost of £24 compared to olanzapine over a 5-year period, corresponding to a £1302 incremental cost-effectiveness ratio. The higher acquisition cost of asenapine was roughly offset by the healthcare savings conferred through its greater efficacy in treating these patients. The model shows that benefits were driven by earlier response to asenapine during acute treatment and were maintained during longer-term follow-up. RESULTS were sensitive to changes in key parameters including short and longer-term efficacy, unit cost, and utilities, but conclusions remained relatively robust. CONCLUSIONS: RESULTS suggest that asenapine is a cost-effective alternative to olanzapine in mixed episode BD-I patients, and may have specific advantages in this population, potentially leading to healthcare sector savings and improved outcomes. Limitations of the analysis stem from gaps in clinical and economic evidence for these patients and should be addressed by future clinical trials.


Assuntos
Benzodiazepinas/economia , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/economia , Compostos Heterocíclicos de 4 ou mais Anéis/economia , Antipsicóticos/efeitos adversos , Antipsicóticos/economia , Antipsicóticos/uso terapêutico , Benzodiazepinas/efeitos adversos , Benzodiazepinas/uso terapêutico , Ensaios Clínicos como Assunto , Análise Custo-Benefício , Dibenzocicloeptenos , Feminino , Compostos Heterocíclicos de 4 ou mais Anéis/efeitos adversos , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Humanos , Masculino , Cadeias de Markov , Modelos Econômicos , Olanzapina , Anos de Vida Ajustados por Qualidade de Vida , Medicina Estatal/economia , Reino Unido , Aumento de Peso/efeitos dos fármacos
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