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1.
Microbiol Spectr ; : e0041624, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39162498

RESUMO

Recent evidence has revealed that the reorganization of nuclear domains is largely mediated by liquid-liquid phase separation (LLPS). During viral infection, numerous nuclear domains undergo significant changes through LLPS for and against the replication of the virus. However, the regulatory mechanism of LLPS in response to viral infection and its detailed functions in viral replication remain unclear. In this study, we found that the activity of the nucleolar protein NPM1, a remodeling factor for the chromatin-like structure of adenovirus DNA, to induce LLPS is required for deposition of adenovirus core protein VII in a subnuclear domain, the virus-induced post-replication (ViPR) body, in the late phases of infection. The interaction between NPM1 and protein VII was responsible for initiating LLPS. The inhibition of LLPS by 1,6-hexanediol treatment resulted in the dispersion of protein VII from the ViPR bodies. These findings suggest that protein VII accumulates in the ViPR bodies in concert with the LLPS formation of NPM1 triggered by protein VII. After photobleaching of EGFP-NPM1 in the ViPR bodies, EGFP-NPM1 showed a relatively fast recovery half-time, indicating the fluid-like properties of NPM1 in this compartment. Importantly, NPM1 depletion decreased the genome packaging in the viral capsids, possibly owing to the formation of a defective adenovirus core. This study highlights the dynamic interplay between viral pathogens and the host nucleus for the reorganization of membrane-less compartments that facilitate their replication. IMPORTANCE: In this study, we explored how adenoviruses utilize a process known as liquid-liquid phase separation (LLPS) to enhance their replication. We focused on a cellular chromatin remodeling protein, NPM1, which plays a crucial role in nucleolar formation through LLPS. NPM1 facilitates LLPS by interacting with adenovirus protein VII, effectively accumulating protein VII into membrane-less compartments called virus-induced post-replication bodies. NPM1 functions as a molecular chaperone of protein VII to assemble viral chromatin by transferring protein VII to viral DNA. Remarkably, when NPM1 was depleted, this process was disrupted, decreasing viral genome packaging. These findings shed light on a critical aspect of virus-host interactions, illustrating how adenovirus utilizes NPM1-mediated LLPS activity. Our findings provide valuable insights into the dynamic interplay between viruses and the host nucleus.

2.
Int J Hematol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136895

RESUMO

Although bosutinib is generally safe and effective, drug-related toxicities (DRTs) such as diarrhea or increased transaminase levels often lead to treatment discontinuation. To clarify whether a lower initial dose of bosutinib (i.e., starting at 200 mg) would reduce rates of discontinuation due to DRTs, we conducted a phase 2 study of BOsutinib Gradual Increase (BOGI trial, UMIN 000032282) as a second/third-line treatment for chronic myeloid leukemia (CML). Between February 4, 2019 and May 24, 2022, 35 patients were enrolled. The rate of bosutinib discontinuation at 12 months was 25.7% vs. 35.9% in a historical control study (Japanese phase 1/2 study) (p = 0.102). The rate of bosutinib discontinuation due to DRTs was significantly lower, at 11.4% vs. 28.2% (p = 0.015). The incidence of grade 3/4 transaminase elevation was 20% vs. 29% (p = 0.427), while the incidence of diarrhea was 3% vs. 25% (p = 0.009). The median dose intensity of bosutinib was higher (391.7 mg/day vs. 353.9 mg/day). Pharmacokinetic analysis of bosutinib showed that patients who achieved a major molecular response tended to have high trough concentrations. Thus, a low initial dose of bosutinib followed by dose escalation reduced discontinuation due to severe DRTs while maintaining high dose intensity and efficacy.

3.
ESC Heart Fail ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075809

RESUMO

AIMS: This study aimed to investigate the clinical impact of pre-procedural left atrial strain (LAS) in patients undergoing permanent pacemaker implantation (PPI). METHODS AND RESULTS: This single-centre retrospective study enrolled 434 patients who were admitted for transvenous PPI between 2010 and 2020. After excluding patients with persistent atrial fibrillation, PPI for complete atrioventricular block, severe valvular disease, history of open-heart surgery and those without LAS data, 172 patients were analysed. The LAS was measured using commercially available software to calculate the average strain value of the apical four- and two-chamber views before PPI. The primary composite endpoint was hospitalization due to heart failure or cardiovascular death. Cox proportional hazard models were used to evaluate risk factors for the primary composite endpoint. The mean patient age was 78 ± 8 years, and 42% of the patients were men. PPI was performed for sick sinus syndrome in 64% and second-degree atrioventricular block in 36% of the patients. The pre-procedure left atrial reservoir strain (LASr) was 28 ± 11%. The median follow-up period was 4.7 years, and the primary endpoint was observed in 23 (13%) patients. In multivariate Cox proportional risk analysis, LASr was independently associated with the primary composite endpoint (hazard ratio, 1.08 per 1% decrease; 95% confidence interval, 1.02-1.15; P = 0.007). The receiver operating characteristic curve of the LASr for the primary composite endpoint showed a cutoff value of 21% (area under the curve 0.657, P = 0.004). The prognostic impact of LASr was consistent with that of sick sinus syndrome and atrioventricular block. CONCLUSIONS: A decreased pre-procedure LASr was associated with long-term adverse outcomes after PPI use.

4.
J Med Chem ; 67(11): 8757-8790, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38753594

RESUMO

Given the crucial role of the main protease (Mpro) in the replication cycle of SARS-CoV-2, this viral cysteine protease constitutes a high-profile drug target. We investigated peptidomimetic azapeptide nitriles as auspicious, irreversibly acting inhibitors of Mpro. Our systematic approach combined an Mpro active-site scanning by combinatorially assembled azanitriles with structure-based design. Encouraged by the bioactive conformation of open-chain inhibitors, we conceptualized the novel chemotype of macrocyclic azanitriles whose binding mode was elucidated by cocrystallization. This strategy provided a favorable entropic contribution to target binding and resulted in the development of the extraordinarily potent Mpro inhibitor 84 with an IC50 value of 3.23 nM and a second-order rate constant of inactivation, kinac/Ki, of 448,000 M-1s-1. The open-chain Mpro inhibitor 58, along with the macrocyclic compounds 83 and 84, a broad-spectrum anticoronaviral agent, demonstrated the highest antiviral activity with EC50 values in the single-digit micromolar range. Our findings are expected to promote the future development of peptidomimetic Mpro inhibitors as anti-SARS-CoV-2 agents.


Assuntos
Antivirais , Proteases 3C de Coronavírus , Nitrilas , SARS-CoV-2 , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , SARS-CoV-2/efeitos dos fármacos , Nitrilas/química , Nitrilas/farmacologia , Nitrilas/síntese química , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/química , Relação Estrutura-Atividade , Humanos , Compostos Macrocíclicos/farmacologia , Compostos Macrocíclicos/química , Compostos Macrocíclicos/síntese química , Tratamento Farmacológico da COVID-19 , Descoberta de Drogas , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/síntese química , Peptidomiméticos/farmacologia , Peptidomiméticos/química , Peptidomiméticos/síntese química , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/síntese química , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/síntese química
5.
ACS Chem Biol ; 19(5): 1028-1034, 2024 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-38668705

RESUMO

The 3CL protease (3CLpro) is a viral cysteine protease of SARS-CoV-2 and is responsible for the main processing of the viral polyproteins involved in viral replication and proliferation. Despite the importance of 3CLpro as a drug target, the intracellular dynamics of active 3CLpro, including its expression and subcellular localization in SARS-CoV-2-infected cells, are poorly understood. Herein, we report an activity-based probe (ABP) with a clickable alkyne and an irreversible warhead for the SARS-CoV-2 3CL protease. We designed and synthesized two ABPs that contain a chloromethyl ketone (probe 2) or 2,6-dichlorobenzoyloxymethyl ketone (probe 3) reactive group at the P1' site. Labeling of recombinant 3CLpro by the ABPs in the purified and proteome systems revealed that probe 3 displayed ligand-directed and selective labeling against 3CLpro. Labeling of transiently expressed active 3CLpro in COS-7 cells also validated the good target selectivity of probe 3 for 3CLpro. We finally demonstrated that endogenously expressed 3CLpro in SARS-CoV-2-infected cells can be detected by fluorescence microscopy imaging using probe 3, suggesting that active 3CLpro at 5 h postinfection is localized in the juxtanuclear region. To the best of our knowledge, this is the first report investigating the subcellular localization of active 3CLpro by using ABPs. We believe that probe 3 will be a useful chemical tool for acquiring important biological knowledge of active 3CLpro in SARS-CoV-2-infected cells.


Assuntos
Proteases 3C de Coronavírus , SARS-CoV-2 , SARS-CoV-2/enzimologia , Proteases 3C de Coronavírus/metabolismo , Chlorocebus aethiops , Animais , Células COS , Humanos , Cetonas/química , Cetonas/metabolismo , COVID-19/virologia , COVID-19/metabolismo , Sondas Moleculares/química
6.
Environ Pollut ; 347: 123722, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38460589

RESUMO

An understanding of the risk of gene deletion and mutation posed by endocrine-disrupting chemicals (EDCs) is necessary for the identification of etiological reagents for many human diseases. Therefore, the characterization of the genetic traits caused by developmental exposure to EDCs is an important research subject. A new regenerative approach using embryonic stem cells (ESCs) holds promise for the development of stem-cell-based therapies and the identification of novel therapeutic agents against human diseases. Here, we focused on the characterization of the genetic traits and alterations in pluripotency/stemness triggered by phthalate ester derivatives. Regarding their in vitro effects, we reported the abilities of ESCs regarding proliferation, cell-cycle control, and neural ectoderm differentiation. The expression of their stemness-related genes and their genetic changes toward neural differentiation were examined, which led to the observation that the tumor suppressor gene product p53/retinoblastoma protein 1 and its related cascades play critical functions in cell-cycle progression, cell death, and neural differentiation. In addition, the expression of neurogenic differentiation 1 was affected by exposure to di-n-butyl phthalate in the context of cell differentiation into neural lineages. The nervous system is one of the most sensitive tissues to exposure to phthalate ester derivatives. The present screening system provides a good tool for studying the mechanisms underlying the effects of EDCs on the developmental regulation of humans and rodents, especially on the neuronal development of ESCs.


Assuntos
Dibutilftalato , Células-Tronco Embrionárias Murinas , Ácidos Ftálicos , Animais , Humanos , Camundongos , Dibutilftalato/toxicidade , Diferenciação Celular , Ésteres
7.
Int J Colorectal Dis ; 39(1): 12, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38157027

RESUMO

PURPOSE: Transversus abdominis plane (TAP) block is a safe, effective, and promising analgesic procedure, but TAP block only cannot overcome postoperative pain. We conducted a prospective randomized study to evaluate postoperative pain control using multimodal analgesia (MA) combined with a single injection TAP block compared with epidural analgesia (EA) after laparoscopic colon cancer surgery. METHODS: Sixty-seven patients scheduled for elective laparoscopic colon cancer surgery were enrolled in this study and randomized into EA and MA groups. The primary endpoint was the frequency of additional analgesic use until postoperative day (POD) 2. The VAS score, blood pressure, time to bowel movement, time to mobilization, postoperative complications, and length of hospital stay were also compared between the two groups. RESULTS: Sixty-four patients (EA group, n = 33; MA group, n = 31) were analyzed. The patient characteristics did not differ markedly between the two groups. The frequency of additional analgesic use was significantly lower in the MA group than in the EA group (P < 0.001), whereas the VAS score did not differ markedly between the two groups. The postoperative blood pressure on the day of surgery was significantly lower in the MA group than in the EA group (P = 0.016), whereas urinary retention was significantly higher in the EA group than in the MA group (P < 0.001). CONCLUSION: MA combined with a single injection TAP block after laparoscopic colon cancer surgery may be comparable to EA in terms of analgesia and superior to EA in terms of urinary retention.


Assuntos
Analgesia Epidural , Neoplasias do Colo , Laparoscopia , Retenção Urinária , Humanos , Músculos Abdominais , Analgésicos , Analgésicos Opioides , Neoplasias do Colo/cirurgia , Neoplasias do Colo/complicações , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Estudos Prospectivos
8.
Sci Rep ; 13(1): 22977, 2023 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-38151520

RESUMO

This study investigated the utility of periostin, a matricellular protein, as a prognostic biomarker in patients with idiopathic pulmonary fibrosis (IPF) who received nintedanib. Monomeric and total periostin levels were measured by enzyme-linked immunosorbent assay in 87 eligible patients who participated in a multicenter prospective study. Forty-three antifibrotic drug-naive patients with IPF described in previous studies were set as historical controls. Monomeric and total periostin levels were not significantly associated with the change in forced vital capacity (FVC) or diffusing capacity of the lungs for carbon monoxide (DLCO) during any follow-up period. Higher monomeric and total periostin levels were independent risk factors for overall survival in the Cox proportional hazard model. In the analysis of nintedanib effectiveness, higher binarized monomeric periostin levels were associated with more favorable suppressive effects on decreased vital capacity (VC) and DLCO in the treatment group compared with historical controls. Higher binarized levels of total periostin were associated with more favorable suppressive effects on decreased DLCO but not VC. In conclusion, higher periostin levels were independently associated with survival and better therapeutic effectiveness in patients with IPF treated with nintedanib. Periostin assessments may contribute to determining therapeutic strategies for patients with IPF.


Assuntos
Fibrose Pulmonar Idiopática , Periostina , Humanos , Estudos Prospectivos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Capacidade Vital , Biomarcadores , Resultado do Tratamento
9.
Rev. bras. ter. intensiva ; 33(3): 384-393, jul.-set. 2021. tab, graf
Artigo em Inglês, Português | LILACS | ID: biblio-1347302

RESUMO

RESUMO Objetivo: Descrever as práticas clínicas atuais relacionadas à utilização de cânula nasal de alto fluxo por intensivistas pediátricos brasileiros e compará-las com as de outros países. Métodos: Para o estudo principal, foi administrado um questionário a intensivistas pediátricos em países das Américas do Norte e do Sul, Ásia, Europa e Austrália/Nova Zelândia. Comparou-se a coorte brasileira com coortes dos Estados Unidos, Canadá, Reino Unido e Índia. Resultados: Responderam ao questionário 501 médicos, dos quais 127 eram do Brasil. Apenas 63,8% dos participantes brasileiros tinham disponibilidade de cânula nasal de alto fluxo, em contraste com 100% dos participantes no Reino Unido, no Canadá e nos Estados Unidos. Coube ao médico responsável a decisão de iniciar a utilização de uma cânula nasal de alto fluxo segundo responderam 61,2% dos brasileiros, 95,5% dos localizados no Reino Unido, 96,6% dos participantes dos Estados Unidos, 96,8% dos médicos canadenses e 84,7% dos participantes da Índia; 62% dos participantes do Brasil, 96,3% do Reino Unido, 96,6% dos Estados Unidos, 96,8% do Canadá e 84,7% da Índia relataram que o médico responsável era quem definia o desmame ou modificava as regulagens da cânula nasal de alto fluxo. Quando ocorreu falha da cânula nasal de alto fluxo por desconforto respiratório ou insuficiência respiratória, 82% dos participantes do Brasil considerariam uma tentativa com ventilação não invasiva antes da intubação endotraqueal, em comparação com 93% do Reino Unido, 88% dos Estados Unidos, 91,5% do Canadá e 76,8% da Índia. Mais intensivistas brasileiros (6,5%) do que do Reino Unido, Estados Unidos e Índia (1,6% para todos) afirmaram utilizar sedativos com frequência concomitantemente à cânula nasal de alto fluxo. Conclusão: A disponibilidade de cânulas nasais de alto fluxo no Brasil ainda não é difundida. Há algumas divergências nas práticas clínicas entre intensivistas brasileiros e seus colegas estrangeiros, principalmente nos processos e nas tomadas de decisão relacionados a iniciar e desmamar o tratamento com cânula nasal de alto fluxo.


ABSTRACT Objective: To describe current clinical practices related to the use of high-flow nasal cannula therapy by Brazilian pediatric intensivists and compare them with those in other countries. Methods: A questionnaire was administered to pediatric intensivists in North and South America, Asia, Europe, and Australia/New Zealand for the main study. We compared the Brazilian cohort with cohorts in the United States of America, Canada, the United Kingdom, and India Results: Overall, 501 physicians responded, 127 of which were in Brazil. Only 63.8% of respondents in Brazil had a high-flow nasal cannula available, in contrast to 100% of respondents in the United Kingdom, Canada, and the United States. The attending physician was responsible for the decision to start a high-flow nasal cannula according to 61.2% respondents in Brazil, 95.5% in the United Kingdom, 96.6% in the United States, 96.8% in Canada, and 84.7% in India. A total of 62% of respondents in Brazil, 96.3% in the United Kingdom, 96.6% in the United States, 96.8% in Canada, and 84.7% in India reported that the attending physician was responsible for the decision to wean or modify the high-flow nasal cannula settings. When high-flow nasal cannula therapy failed due to respiratory distress/failure, 82% of respondents in Brazil would consider a trial of noninvasive ventilation before endotracheal intubation, compared to 93% in the United Kingdom, 88% in the United States, 91.5% in Canada, and 76.8% in India. More Brazilian intensivists (6.5%) than intensivists in the United Kingdom, United States, and India (1.6% for all) affirmed using sedatives frequently with high-flow nasal cannulas. Conclusion: The availability of high-flow nasal cannulas in Brazil is still not widespread. There are some divergences in clinical practices between Brazilian intensivists and their colleagues abroad, mainly in processes and decision-making about starting and weaning high-flow nasal cannula therapy.


Assuntos
Humanos , Criança , Ventilação não Invasiva , Cânula , Estados Unidos , Brasil , Inquéritos e Questionários , Cuidados Críticos
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