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1.
Nucleic Acids Res ; 50(12): e69, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35325178

RESUMO

The nucleolus is a subnuclear membraneless compartment intimately involved in ribosomal RNA synthesis, ribosome biogenesis and stress response. Multiple optogenetic devices have been developed to manipulate nuclear protein import and export, but molecular tools tailored for remote control over selective targeting or partitioning of cargo proteins into subnuclear compartments capable of phase separation are still limited. Here, we report a set of single-component photoinducible nucleolus-targeting tools, designated pNUTs, to enable rapid and reversible nucleoplasm-to-nucleolus shuttling, with the half-lives ranging from milliseconds to minutes. pNUTs allow both global protein infiltration into nucleoli and local delivery of cargoes into the outermost layer of the nucleolus, the granular component. When coupled with the amyotrophic lateral sclerosis (ALS)-associated C9ORF72 proline/arginine-rich dipeptide repeats, pNUTs allow us to photomanipulate poly-proline-arginine nucleolar localization, perturb nucleolar protein nucleophosmin 1 and suppress nascent protein synthesis. pNUTs thus expand the optogenetic toolbox by permitting light-controllable interrogation of nucleolar functions and precise induction of ALS-associated toxicity in cellular models.


Assuntos
Esclerose Lateral Amiotrófica , Nucléolo Celular , Optogenética/métodos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/metabolismo , Proteína C9orf72/química , Nucléolo Celular/metabolismo , Sistemas de Liberação de Medicamentos , Humanos , Proteínas Nucleares/metabolismo , Inibidores da Síntese de Proteínas/administração & dosagem
2.
Nucleic Acids Res ; 49(10): 5726-5742, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34023907

RESUMO

Appropriate regulation of the Integrated stress response (ISR) and mTORC1 signaling are central for cell adaptation to starvation for amino acids. Halofuginone (HF) is a potent inhibitor of aminoacylation of tRNAPro with broad biomedical applications. Here, we show that in addition to translational control directed by activation of the ISR by general control nonderepressible 2 (GCN2), HF increased free amino acids and directed translation of genes involved in protein biogenesis via sustained mTORC1 signaling. Deletion of GCN2 reduced cell survival to HF whereas pharmacological inhibition of mTORC1 afforded protection. HF treatment of mice synchronously activated the GCN2-mediated ISR and mTORC1 in liver whereas Gcn2-null mice allowed greater mTORC1 activation to HF, resulting in liver steatosis and cell death. We conclude that HF causes an amino acid imbalance that uniquely activates both GCN2 and mTORC1. Loss of GCN2 during HF creates a disconnect between metabolic state and need, triggering proteostasis collapse.


Assuntos
Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/genética , Estresse Fisiológico/genética , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Códon/genética , Ontologia Genética , Fígado/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Polirribossomos/metabolismo , Proteínas Serina-Treonina Quinases/genética , Inibidores da Síntese de Proteínas/administração & dosagem , Inibidores da Síntese de Proteínas/farmacologia , Quinazolinonas/administração & dosagem , Quinazolinonas/farmacologia , RNA de Transferência/genética , RNA de Transferência/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos
3.
Behav Brain Res ; 403: 113132, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33485873

RESUMO

Memory formation depends upon several parametric training conditions. Among them, trial number and inter-trial interval (ITI) are key factors to induce long-term retention. However, it is still unclear how individual training trials contribute to mechanisms underlying memory formation and stabilization. Contextual conditioning in Neohelice granulata has traditionally elicited associative long-term memory (LTM) after 15 spaced (ITI = 3 min) trials. Here, we show that LTM in crabs can be induced after only two training trials by increasing the ITI to 45 min (2t-LTM) and maintaining the same training duration as in traditional protocols. This newly observed LTM was preserved for at least 96 h, exhibiting protein synthesis dependence during consolidation and reconsolidation as well as context-specificity. Moreover, we demonstrate that 2t-LTM depends on inter-trial and post-training ERK activation showing a faster phosphorylation after the second trial compared to the first one. In summary, we present a new training protocol in crabs through a reduced number of trials showing associative features similar to traditional spaced training. This novel protocol allows for intra-training manipulation and the assessment of individual trial contribution to LTM formation.


Assuntos
Comportamento Animal/fisiologia , Braquiúros/fisiologia , Consolidação da Memória/fisiologia , Memória de Longo Prazo/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Prática Psicológica , Inibidores de Proteínas Quinases/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Animais , Cicloeximida/farmacologia , Dimetil Sulfóxido/administração & dosagem , Flavonoides/farmacologia , Masculino , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores da Síntese de Proteínas/administração & dosagem
4.
Int J Mol Sci ; 21(15)2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32748831

RESUMO

It is well known that long-term consolidation of newly acquired information, including information related to social fear, require de novo protein synthesis. However, the temporal dynamics of protein synthesis during the consolidation of social fear memories is unclear. To address this question, mice received a single systemic injection with the protein synthesis inhibitor, anisomycin, at different time-points before or after social fear conditioning (SFC), and memory was assessed 24 h later. We showed that anisomycin impaired the consolidation of social fear memories in a time-point-dependent manner. Mice that received anisomycin 20 min before, immediately after, 6 h, or 8 h after SFC showed reduced expression of social fear, indicating impaired social fear memory, whereas anisomycin caused no effects when administered 4 h after SFC. These results suggest that consolidation of social fear memories requires two stages of protein synthesis: (1) an initial stage starting during or immediately after SFC, and (2) a second stage starting around 6 h after SFC and lasting for at least 5 h.


Assuntos
Anisomicina/farmacologia , Medo/efeitos dos fármacos , Memória/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Animais , Anisomicina/administração & dosagem , Condicionamento Clássico/efeitos dos fármacos , Masculino , Camundongos , Inibidores da Síntese de Proteínas/administração & dosagem , Fatores de Tempo
5.
Acta Pharmacol Sin ; 41(5): 698-705, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32047261

RESUMO

Norditerpenoids and dinorditerpenoids represent diterpenoids widely distributed in the genus Podocarpus with notable chemical structures and biological activities. We previously reported that nagilactone E (NLE), a dinorditerpenoid isolated from Podocarpus nagi, possessed anticancer effects against lung cancer cells in vitro. In this study we investigated the in vivo effect of NLE against lung cancer as well as the underlying mechanisms. We administered NLE (10 mg·kg-1·d-1, ip) to CB-17/SCID mice bearing human lung cancer cell line A549 xenograft for 3 weeks. We found that NLE administration significantly suppressed the tumor growth without obvious adverse effects. Thereafter, RNA sequencing (RNA-seq) analysis was performed to study the mechanisms of NLE. The effects of NLE on A549 cells have been illustrated by GO and pathway enrichment analyses. CMap dataset analysis supported NLE to be a potential protein synthesis inhibitor. The inhibitory effect of NLE on synthesis of total de novo protein was confirmed in Click-iT assay. Using the pcDNA3-RLUC-POLIRES-FLUC luciferase assay we further demonstrated that NLE inhibited both cap-dependent and cap-independent translation. Finally, molecular docking revealed the low-energy binding conformations of NLE and its potential target RIOK2. In conclusion, NLE is a protein synthesis inhibitor with anticancer activity.


Assuntos
Fator 4 Ativador da Transcrição/antagonistas & inibidores , Antineoplásicos/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Diterpenos/farmacologia , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Inibidores da Síntese de Proteínas/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Células A549 , Fator 4 Ativador da Transcrição/biossíntese , Fator 4 Ativador da Transcrição/genética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Biologia Computacional , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Inibidor de Quinase Dependente de Ciclina p21/genética , Diterpenos/administração & dosagem , Diterpenos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos SCID , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/biossíntese , Fator 2 Relacionado a NF-E2/genética , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Inibidores da Síntese de Proteínas/administração & dosagem , Inibidores da Síntese de Proteínas/isolamento & purificação , Fator de Transcrição STAT3/biossíntese , Fator de Transcrição STAT3/genética , Células Tumorais Cultivadas
6.
Anticancer Agents Med Chem ; 20(2): 264-273, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31736447

RESUMO

BACKGROUND: Colorectal cancer is the third most commonly diagnosed cancer in the world, causing many deaths every year. Combined chemotherapy has opened a new horizon in treating colorectal cancer. The objective of the present study is to investigate the activity of oxaliplatin in combination with emetine and patulin against colorectal cancer models. METHODS: IC50 values of oxaliplatin, emetine and patulin were determined against human colorectal cancer cell lines (HT-29 and Caco-2) using MTT reduction assay. Synergistic, antagonistic and additive effects from the selected binary combinations were determined as a factor of sequence of administration and added concentrations. Proteomics was carried out to identify the proteins which were accountable for combined drug action applying to the selected drug combination. RESULTS: Oxaliplatin in combination with patulin produced synergism against human colorectal cancer models depending on dose and sequence of drug administration. Bolus administration of oxaliplatin with patulin proved to be the best in terms of synergistic outcome. Altered expressions of nine proteins (ACTG, PROF1, PPIA, PDIA3, COF1, GSTP1, ALDOA, TBA1C and TBB5) were considered for combined drug actions of oxaliplatin with patulin. CONCLUSION: Bolus administration of oxaliplatin with patulin has the potential to be used in the treatment of colorectal cancer, and would warrant further evaluation using suitable animal model.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Emetina/farmacologia , Oxaliplatina/farmacologia , Patulina/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Antineoplásicos/administração & dosagem , Células CACO-2 , Sinergismo Farmacológico , Quimioterapia Combinada , Emetina/administração & dosagem , Células HT29 , Humanos , Mutagênicos/administração & dosagem , Mutagênicos/farmacologia , Oxaliplatina/administração & dosagem , Patulina/administração & dosagem , Inibidores da Síntese de Proteínas/administração & dosagem
7.
J Med Chem ; 63(8): 3817-3833, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31820982

RESUMO

Kinetic target-guided synthesis (KTGS) is an original discovery strategy allowing a target to catalyze the irreversible synthesis of its own ligands from a pool of reagents. Although pioneered almost two decades ago, it only recently proved its usefulness in medicinal chemistry, as exemplified by the increasing number of protein targets used, the wider range of target and pocket types, and the diversity of therapeutic areas explored. In recent years, two new leads for in vivo studies were released. Amidations and multicomponent reactions expanded the armamentarium of reactions beyond triazole formation and two new examples of in cellulo KTGS were also disclosed. Herein, we analyze the origins and the chemical space of both KTGS ligands and warhead-bearing reagents. We review the KTGS timeline focusing on recent cases in order to give medicinal chemists the full scope of this strategy which has great potential for hit discovery and hit or lead optimization.


Assuntos
Química Farmacêutica/tendências , Sistemas de Liberação de Medicamentos/tendências , Descoberta de Drogas/tendências , Inibidores de Proteases/química , Inibidores da Síntese de Proteínas/química , Animais , Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Descoberta de Drogas/métodos , Humanos , Cinética , Inibidores de Proteases/administração & dosagem , Inibidores de Proteases/farmacocinética , Inibidores da Síntese de Proteínas/administração & dosagem , Inibidores da Síntese de Proteínas/farmacocinética
8.
Laryngoscope ; 130(10): 2455-2460, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31808957

RESUMO

OBJECTIVE: To report audiovestibular outcomes following endolymphatic shunt surgery (ELS) and intratympanic gentamicin injections (ITG) in patients with Meniere's disease (MD). STUDY DESIGN: Retrospective matched cohort study METHODS: Patients with MD refractory to medical management between 2004 and 2017 were reviewed: 44 patients underwent ELS and had outcomes available, while 27 patients underwent ITG and had outcomes available. Mean follow-up durations for the ELS and ITG groups were 39.1 and 43.3 months, respectively. Twenty-six patients from the ELS group and 24 patients from the ITG group were then included in a pretreatment hearing- and age-matched analysis. Main outcome measures were successful control of vertigo, pure-tone average (PTA; 0.5, 1, 2 and 4 kHz), word recognition score (WRS), and treatment complications. RESULTS: A matched analysis showed vertigo control rates of 73.1% in the ELS group and 66.8% in the ITG group, which were not significantly different (P = .760). The change in PTA following treatment was statistically similar between the ELS group (6.2 dB) and ITG group (4.6 dB) (P = .521), while the change in WRS for the ELS group (+3.9 %) was significantly more favorable than the ITG group (-13.6 %) (P = .046). Chronic post-treatment unsteadiness was reported in 25.0% of the ITG group and was not encountered in the ELS group (P = .009). CONCLUSION: ELS provided successful vertigo control at least as well as ITG with a lower incidence of audiovestibular complications. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:2455-2460, 2020.


Assuntos
Anastomose Endolinfática , Gentamicinas/uso terapêutico , Doença de Meniere/terapia , Inibidores da Síntese de Proteínas/uso terapêutico , Audiometria de Tons Puros , Feminino , Gentamicinas/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Síntese de Proteínas/administração & dosagem , Estudos Retrospectivos , Membrana Timpânica/efeitos dos fármacos
9.
Otol Neurotol ; 41(1): 1-10, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31789967

RESUMO

OBJECTIVE: To compare the functional outcomes and complications of intratympanic gentamicin (ITG) versus intratympanic corticosteroids (ITC) in Menière's disease. DATA SOURCES: An electronic search was conducted in the Cochrane Library, PubMed, and Embase databases on February 3, 2019. Articles written in English, Dutch, German, French, or Turkish language were included. STUDY SELECTION: Study inclusion criteria were: 1) patients diagnosed with definite Menière's disease according to the criteria of the American Academy of Otolaryngology-Head and Neck Surgery, 2) treated with ITG or ITC in a comparison study, and 3) reported subjective and objective outcomes concerning Menière's disease. DATA EXTRACTION: The quality of eligible studies was assessed according to an adjusted version of the Cochrane Risk of Bias tool. The extracted data were study characteristics (study design, publication year, and number of relevant patients), patient's characteristics (sex and age), disease characteristics (uni or bilateral and duration of Menière's disease), treatment protocol, and different therapeutic outcomes (vertigo, tinnitus, aural fullness, and hearing loss). DATA SYNTHESIS: A total of eight articles were included for data extraction and analysis. For subjective outcomes, ITG was slightly favored compared to intratympanic corticosteroids. This was significant only in three studies (p < 0.05). For objective outcomes and complications, no significant differences were seen. CONCLUSIONS: The result of this systematic review shows some benefit of ITG over ITC for subjective outcomes and no difference regarding objective outcomes or complication rate. However, this superiority of ITG is rather weak. Both interventions can be effectively and safely used in controlling Menière's disease in acute situations.


Assuntos
Anti-Inflamatórios/administração & dosagem , Gentamicinas/administração & dosagem , Doença de Meniere/tratamento farmacológico , Inibidores da Síntese de Proteínas/administração & dosagem , Corticosteroides/administração & dosagem , Aminoglicosídeos/administração & dosagem , Dexametasona/administração & dosagem , Feminino , Humanos , Injeção Intratimpânica , Masculino , Metilprednisolona/administração & dosagem , Pessoa de Meia-Idade
10.
J Biomed Sci ; 26(1): 72, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31597574

RESUMO

BACKGROUND: Transforming growth factor (TGF) family members play important roles in the regulation of corneal integrity, and the pathogenesis of corneal fibrosis. Currently, there are no effective agents targeting TGF-ß signaling to diminish corneal fibrosis. Glucosamine (GlcN), which is widely used in the treatment of osteoarthritis, abrogates the morphologic effects of TGF-ß2 on retinal pigmented epithelial cells in a mouse disease model. Here, we sought to determine whether GlcN would exert beneficial effects against TGF-ß1-induced corneal fibrosis. METHODS: In human corneal fibroblasts (HCFs) treated with GlcN, the expression of Krüppel-like factor 4 (KLF4) and its downstream signaling effects were determined in the presence and absence of TGF-ß1 using immunoblot analysis. We further explored GlcN inhibition of fibroblast-to-myofibroblast differentiation via KLF4 siRNA. The effect of cycloheximide on KLF4 protein levels with or without GlcN administration was assessed to determine whether GlcN affects the stability of the KLF4 protein. RESULTS: In HCFs, GlcN induced the expression of KLF4, which regulated the maturation and maintenance of the ocular surface. GlcN partially suppressed the TGF-ß1-induced expression of alpha-smooth muscle actin (α-SMA) and reduced the collagen contraction capacity in HCFs, suggesting a decrease in fibroblast-to-myofibroblast differentiation. This effect appeared to be mediated through suppression of Smad2 phosphorylation and ERK-dependent signaling. The levels of KLF4 mRNA were increased by GlcN and decreased by TGF-ß1 and the TGF-ß1-induced α-SMA mRNA expression was upregulated when the KLF4 gene was silenced. GlcN also appeared to stabilize the KLF4 protein, reducing its turnover in corneal fibroblasts. CONCLUSION: These findings shed light on a novel mechanism by which GlcN suppresses TGF-ß1-induced fibroblast-to-myofibroblast differentiation through the upregulation of KLF4 expression. Current strategies for treating corneal fibrosis were not effective. Elevating KLF4 levels through the use of GlcN might provide an effective alternative to alleviate the development and progression of corneal fibrosis.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Doenças da Córnea/tratamento farmacológico , Fibrose/tratamento farmacológico , Glucosamina/farmacologia , Fatores de Transcrição Kruppel-Like/genética , Fator de Crescimento Transformador beta1/genética , Doenças da Córnea/etiologia , Doenças da Córnea/genética , Cicloeximida/administração & dosagem , Fibroblastos/efeitos dos fármacos , Fibrose/etiologia , Fibrose/genética , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/metabolismo , Miofibroblastos/fisiologia , Substâncias Protetoras/farmacologia , Inibidores da Síntese de Proteínas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo
11.
Otol Neurotol ; 40(4): 419-429, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30870347

RESUMO

OBJECTIVES: In recent decades, intratympanic gentamicin (ITG) has increasingly been used to treat intractable Menière's disease (MD). We performed a meta-analysis of pooled clinical outcomes, exploring whether ITG was effective and safe. DATA SOURCES: Cochrane Library database, Embase, and Medline. STUDY SELECTION: We searched scientific and medical databases to March 2018 for articles evaluating clinical outcomes after ITG treatment of intractable MD according to the American Academy of Otolaryngology Head and Neck Surgery (AAO-HNS) guidelines. DATA EXTRACTION: We performed a meta-analysis to evaluate treatment efficacy and safety. Quantitative and descriptive information of included RCTs was obtained. DATA SYNTHESIS: We ultimately evaluated 49 of the initially retrieved 1,062 citations (the 49 articles included data from a total of 2,344 MD patients). In almost all studies, patients served as their own controls; "before-and-after" clinical outcomes were reported. The I metric was used to explore heterogeneity. CONCLUSION: Overall, our results seem to provide the limited evidence about efficacy and toxicity effects of ITG. However, clinical outcomes require further confirmation; many included studies were poorly designed, less than 2 years for reporting results in MD are in the majority of patients. More long-term prospective follow-up, high-quality, large-scale, randomized controlled trials are needed to confirm that ITG is safe and effective when used to treat intractable MD.


Assuntos
Gentamicinas/administração & dosagem , Doença de Meniere/tratamento farmacológico , Inibidores da Síntese de Proteínas/administração & dosagem , Humanos , Injeção Intratimpânica , Resultado do Tratamento
12.
Laryngoscope ; 129(1): 216-221, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30284276

RESUMO

OBJECTIVE: To evaluate outcomes of intratympanic (IT) dexamethasone and gentamicin in Ménière Disease (MD). METHODS: Charts of adult patients with unilateral definite MD receiving IT gentamicin or dexamethasone from 2005 to 2017 were retrospectively reviewed. All patients had at least 6 months follow-up. Failure in each group was defined as the need for more aggressive therapy. Prior to 2011, all patient received IT gentamicin, administered as primary therapy after failure of conservative treatment measures. Gentamicin was administered every 2 weeks, up to three injections, until vertigo control was achieved. Beginning in 2011, the treatment protocol shifted to IT dexamethasone as initial treatment, with gentamicin used for dexamethasone failures. Dexamethasone was administered weekly for up to three injections. Treatments could be repeated if symptoms recurred. RESULTS: Thirty-three patients received IT dexamethasone, and 70 patients received IT gentamicin. Dexamethasone patients received a mean of 3.3 injections compared to 2.7 in the gentamicin group (P = 0.011). There were 12 (38%) failures in the dexamethasone group and only seven (10%) gentamicin failures (P = 0.025). No patients failed both treatments. The mean time to failure in the dexamethasone group was 5 months, whereas in the gentamicin group it was 27 months. Change in pure tone audiometry from baseline was not different between treatment groups (P = 0.30). CONCLUSION: Subjects receiving IT gentamicin required fewer injections and had a significantly longer time to failure than IT dexamethasone. Audiometric outcomes were similar between the groups. The use of IT gentamicin as initial therapy for early and long-term control of MD is safe and effective. LEVEL OF EVIDENCE: 3 Laryngoscope, 129:216-221, 2019.


Assuntos
Dexametasona/administração & dosagem , Gentamicinas/administração & dosagem , Glucocorticoides/administração & dosagem , Doença de Meniere/tratamento farmacológico , Inibidores da Síntese de Proteínas/administração & dosagem , Adulto , Audiometria de Tons Puros , Feminino , Humanos , Injeção Intratimpânica , Estimativa de Kaplan-Meier , Masculino , Estudos Retrospectivos , Falha de Tratamento
13.
J Antimicrob Chemother ; 74(1): 1-5, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30307507

RESUMO

Protein synthesis inhibitor antibiotics inhibit synthesis of new proteins, including exotoxins and other important virulence determinants in Staphylococcus aureus. A summary of the literature regarding the use of adjunctive protein synthesis inhibitors for toxin suppression in the setting of S. aureus infections is presented.


Assuntos
Antibacterianos/administração & dosagem , Toxinas Bacterianas/biossíntese , Inibidores da Síntese de Proteínas/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Toxinas Bacterianas/antagonistas & inibidores , Humanos , Inibidores da Síntese de Proteínas/farmacologia
14.
J Am Vet Med Assoc ; 253(9): 1164-1168, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30311520

RESUMO

CASE DESCRIPTION A client-owned 2-year-old 1.8-kg (4-lb) male pet Rouen duck (Anas platyrhynchos domesticus) was evaluated because of severe swelling around the left eye following traumatic injury to the upper and lower eyelids and 2 associated surgeries that resulted in the removal of the entire upper and lower eyelid margins. CLINICAL FINDINGS At initial evaluation, ankyloblepharon of the left eye was observed, with no upper or lower eyelid margins and a large, round, fluctuant subcutaneous mass over the left orbit. Orbital exploration and histologic examination revealed a benign cyst consisting of fibrous tissue, conjunctiva, and skeletal muscle bundles. Bacterial culture of cystic fluid yielded few Staphylococcus delphini. TREATMENT AND OUTCOME Excision of the cyst and evisceration of the left globe were performed, and once daily treatment with orally administered enrofloxacin suspension (12.6 mg/kg [5.7 mg/lb]) and meloxicam (1 mg/kg [0.45 mg/lb]) was initiated. Over the next 4 days, the cyst redeveloped and progressively enlarged. Accumulated fluid was aspirated from the cyst, and 20 mg of gentamicin was injected intraorbitally with ultrasound guidance. Over the subsequent 27-month period, no recurrence of clinical signs or adverse effects were reported by the owner. CLINICAL RELEVANCE To the authors' knowledge, this is the first report of cyst formation after adnexal injury and evisceration in birds and its successful treatment with intralesional gentamicin injection. Findings emphasized the importance of preserving lacrimal puncta during adnexal or eye removal surgeries in birds. Intralesional injection of gentamicin with the goal of destroying fluid-producing cells may be a safe and effective way to treat intraorbital cysts in birds and other species, although additional research would be required to confirm this.


Assuntos
Doenças das Aves/terapia , Cistos/veterinária , Patos , Doenças Palpebrais/veterinária , Pálpebras/lesões , Doença Iatrogênica/veterinária , Animais , Doenças das Aves/etiologia , Cistos/etiologia , Cistos/terapia , Evisceração do Olho/veterinária , Doenças Palpebrais/complicações , Doenças Palpebrais/patologia , Gentamicinas/administração & dosagem , Gentamicinas/uso terapêutico , Masculino , Inibidores da Síntese de Proteínas/administração & dosagem , Inibidores da Síntese de Proteínas/uso terapêutico
15.
Behav Neurosci ; 132(2): 99-105, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29672107

RESUMO

Mixed evidence exists regarding the role of N-methyl-D-aspartate (NMDA) receptors in memory reconsolidation. We provide no evidence that NMDA receptors are involved with memory reconsolidation, but instead demonstrate that prereactivation systemic MK-801 injection, combined with postreactivation intrabasolateral amygdala (BLA) cycloheximide infusion, produces a delayed potentiation of extinction learning. These data suggest that an interaction between NMDA antagonism and protein synthesis inhibition may enhance extinction by exerting effects outside of the intended reconsolidation manipulation window. The present work demonstrates a novel pharmacological enhancement of extinction, and underscores the importance of employing proper control procedures in reconsolidation research. (PsycINFO Database Record


Assuntos
Cicloeximida/administração & dosagem , Discriminação Psicológica/efeitos dos fármacos , Maleato de Dizocilpina/administração & dosagem , Extinção Psicológica/efeitos dos fármacos , Memória/efeitos dos fármacos , Psicotrópicos/administração & dosagem , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Animais , Discriminação Psicológica/fisiologia , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Extinção Psicológica/fisiologia , Medo/efeitos dos fármacos , Medo/fisiologia , Reação de Congelamento Cataléptica/efeitos dos fármacos , Reação de Congelamento Cataléptica/fisiologia , Masculino , Memória/fisiologia , Inibidores da Síntese de Proteínas/administração & dosagem , Ratos Long-Evans , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Fatores de Tempo
16.
Auris Nasus Larynx ; 45(1): 39-44, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28292626

RESUMO

OBJECTIVE: In this retrospective study the aim of the authors was to examine the effect of gentamicin on the individual semicircular canals after low dose, single injection intratympanal gentamicin therapy in Meniere's disease. METHODS: Data of 32 patients treated between 2011 and 2015 were collected. The high frequency, high acceleration vestibuloocular reflex (VOR) gain was measured in the individual semicircular canals using video head impulse test immediately before the first intratympanal gentamicin instillation and approximately two months later. RESULTS: In all cases 'AAO-HNS Class A' vertigo control could be attained at least for several months. In 13 cases only one instillation was necessary. In the other 19 cases the attacks returned after a few months. In 11 cases the injection had to be repeated a second time, in 4 cases 3 injections, in 2 cases 4, in 1 case 5 injections and in another 6 injections were necessary. The initial VOR gain was normal in all cases and two months after one injection it decreased in average by 40% in a highly significant manner. However, there were cases in which, although the patients became free of attacks, the gain values remained normal. CONCLUSION: It was possible to demonstrate a significant correlation between the gain decrease of the individual canals. There was no prognostic correlation between the initial gain decrease after the first injection and the necessity of further injections. Gain values also decreased slightly but significantly in the lateral and posteriors canals on the contralateral, untreated side, possibly because of the missing disfacilitation from the treated side.


Assuntos
Gentamicinas/farmacologia , Doença de Meniere/tratamento farmacológico , Inibidores da Síntese de Proteínas/farmacologia , Reflexo Vestíbulo-Ocular/efeitos dos fármacos , Canais Semicirculares/efeitos dos fármacos , Adulto , Feminino , Gentamicinas/administração & dosagem , Teste do Impulso da Cabeça , Humanos , Injeção Intratimpânica , Masculino , Doença de Meniere/fisiopatologia , Inibidores da Síntese de Proteínas/administração & dosagem , Estudos Retrospectivos , Vertigem/tratamento farmacológico
17.
J Invest Dermatol ; 138(4): 836-843, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29106929

RESUMO

Nagashima-type palmoplantar keratosis (NPPK) is an autosomal recessive skin disorder with a high, unmet medical need that is caused by mutations in SERPINB7. Almost all NPPK patients carry the founder nonsense mutation c.796C>T (p.Arg266Ter) in the last exon of SERPINB7. Here we sought to determine whether topical nonsense-suppression (readthrough) therapy using gentamicin is applicable to NPPK. First, we demonstrated that gentamicin enhanced readthrough activity in cells transfected with SERPINB7 cDNA carrying the mutation and promoted full-length SERPINB7 protein synthesis in NPPK keratinocytes. We next conducted an investigator-blinded, randomized, bilaterally controlled compassionate use study of topical gentamicin in which five NPPK patients with c.796C>T were enrolled. Patients' self-reported improvement of hyperkeratosis was significantly greater on the gentamicin side than the control side (P = 0.0349). In two patients, hyperkeratosis was improved on the gentamicin side, as determined by a blinded-investigator assessment. These results indicate the therapeutic potential of topical gentamicin for NPPK. Unexpectedly, we also found that mutant SERPINB7 mRNAs harboring r.796c>u were degraded by nonsense-mediated mRNA decay. Furthermore, the truncated SERPINB7 protein was degraded via a proteasome-mediated pathway. These findings provide important insights into the mRNA/protein quality-control system in humans, which could be a potential therapeutic target for genetic diseases.


Assuntos
DNA/genética , Gentamicinas/administração & dosagem , Ceratodermia Palmar e Plantar/genética , Mutação , Degradação do RNAm Mediada por Códon sem Sentido/efeitos dos fármacos , Serpinas/genética , Administração Tópica , Códon sem Sentido , Análise Mutacional de DNA , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/patologia , Ceratodermia Palmar e Plantar/tratamento farmacológico , Ceratodermia Palmar e Plantar/patologia , Inibidores da Síntese de Proteínas/administração & dosagem , Serpinas/metabolismo
18.
Neurobiol Learn Mem ; 145: 151-164, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29030298

RESUMO

Consolidated memories can become destabilized during reactivation, resulting in a transient state of instability, a process that has been hypothesized to underlie long-term memory updating. Consistent with this notion, relatively remote memories, which are resistant to standard destabilization procedures, are reliably destabilized when novel information (i.e., the opportunity for memory updating) is present during reactivation. We have also shown that cholinergic muscarinic receptor (mAChR) activation can similarly destabilize consolidated object memories. Synaptic protein degradation via the ubiquitin proteasome system (UPS) has previously been linked to destabilization of fear and object-location memories. Given the role of calcium in regulating proteasome activity, we hypothesized that activation of cholinergic receptors, specifically M1 mAChRs, stimulates the UPS via inositol triphosphate receptor (IP3R)-mediated release of intracellular calcium stores to facilitate object memory destabilization. We present converging evidence for this hypothesis, which we tested using a modified spontaneous object recognition task for rats and microinfusions into perirhinal cortex (PRh), a brain region strongly implicated in object memory. We extend our previous findings by demonstrating that M1 mAChRs are necessary for novelty-induced object memory destabilization. We also show that proteasome inhibition or IP3R antagonism in PRh prevents object memory destabilization induced by novelty or M1 mAChR stimulation. These results establish an intracellular pathway linking M1 receptors, IP3Rs, and UPS activity to object memory destabilization and suggest a previously unacknowledged role for cholinergic signaling in long-term memory modification and storage.


Assuntos
Memória de Longo Prazo/fisiologia , Córtex Perirrinal/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Receptor Muscarínico M1/metabolismo , Animais , Anisomicina/administração & dosagem , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Masculino , Inibidores da Síntese de Proteínas/administração & dosagem , Ratos Long-Evans , Reconhecimento Psicológico/fisiologia , Ubiquitina/metabolismo
19.
J Clin Invest ; 127(8): 3028-3038, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28691931

RESUMO

BACKGROUND: Recessive dystrophic epidermolysis bullosa (RDEB) is an incurable disease caused by mutations in the gene encoding type VII collagen, the major component of anchoring fibrils (AF). We previously demonstrated that gentamicin produced functional type VII collagen in RDEB cells harboring nonsense mutations. Herein, we determined whether topical or intradermal gentamicin administration induces type VII collagen and AFs in RDEB patients. METHODS: A double-blind, placebo-controlled pilot trial assessed safety and efficacy of topical and intradermal gentamicin in 5 RDEB patients with nonsense mutations. The topical arm tested 0.1% gentamicin ointment or placebo application 3 times daily at 2 open erosion sites for 2 weeks. The intradermal arm tested daily intradermal injection of gentamicin solution (8 mg) or placebo into 2 intact skin sites for 2 days in 4 of 5 patients. Primary outcomes were induction of type VII collagen and AFs at the test sites and safety assessment. A secondary outcome assessed wound closure of topically treated erosions. RESULTS: Both topical and intradermal gentamicin administration induced type VII collagen and AFs at the dermal-epidermal junction of treatment sites. Newly created type VII collagen varied from 20% to 165% of that expressed in normal human skin and persisted for 3 months. Topical gentamicin corrected dermal-epidermal separation, improved wound closure, and reduced blister formation. There were no untoward side effects from gentamicin treatments. Type VII collagen induction did not generate anti-type VII collagen autoantibodies in patients' blood or skin. CONCLUSION: Topical and intradermal gentamicin suppresses nonsense mutations and induces type VII collagen and AFs in RDEB patients. Gentamicin therapy may provide a readily available treatment for RDEB patients with nonsense mutations. TRIAL REGISTRATION: ClinicalTrials.gov NCT02698735. FUNDING: Epidermolysis Bullosa Research Partnership, Epidermolysis Bullosa Medical Research Foundation, NIH, and VA Merit Award.


Assuntos
Colágeno Tipo VII/metabolismo , Epidermólise Bolhosa Distrófica/tratamento farmacológico , Gentamicinas/uso terapêutico , Inibidores da Síntese de Proteínas/uso terapêutico , Administração Tópica , Adulto , Alelos , Autoanticorpos/química , Criança , Códon sem Sentido , Colágeno Tipo VII/genética , Método Duplo-Cego , Epidermólise Bolhosa Distrófica/genética , Epidermólise Bolhosa Distrófica/metabolismo , Feminino , Genes Recessivos , Gentamicinas/administração & dosagem , Humanos , Injeções Intradérmicas , Queratinócitos/citologia , Masculino , Segurança do Paciente , Projetos Piloto , Inibidores da Síntese de Proteínas/administração & dosagem , Pele/efeitos dos fármacos , Resultado do Tratamento , Cicatrização
20.
Acta Otolaryngol ; 137(2): 136-143, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27608722

RESUMO

CONCLUSIONS: One-shot, low-dose intra-tympanic gentamicin (ITG) treatment was effective and safe for Ménière's disease (MD) patients. Head thrust test (HTT) and vestibular evoked myogenic potentials (VEMPs) test could be used as endpoint indicators for vertigo control in MD patients. OBJECTIVES: The present study is to explore end-point indicators of ITG injection in MD. METHODS: Patients with MD were reviewed from June 2012 to March 2014. Single-shot ITG at a concentration of 30 mg/ml was administered to patients. The sensitivity and specificity of HTT and VEMPs for vertigo control were measured. RESULTS: All 37 patients with a median follow-up of 26 months were included. Of those 37 patients, 24 patients (64.9%) obtained class A vertigo control and seven patients (18.9%) obtained class B vertigo control. Only six patients had class C control (16.2%). The sensitivity and specificity of HTT for vertigo control were 74.2% and 50.0%. Meanwhile, the sensitivity and specificity of VEMPs threshold were 83.9% and 33.3%. When combined HTT and VEMPs, sensitivity and specificity were 93.5% and 66.7%. Based on the four-tone average thresholds at 0.5, 1, 2, 3 kHz, 78.4% patients had no significant change in PTA and 16.2% patients experienced significant improvement.


Assuntos
Gentamicinas/administração & dosagem , Doença de Meniere/tratamento farmacológico , Inibidores da Síntese de Proteínas/administração & dosagem , Adulto , Idoso , Feminino , Teste do Impulso da Cabeça , Humanos , Injeção Intratimpânica , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Sensibilidade e Especificidade , Potenciais Evocados Miogênicos Vestibulares , Adulto Jovem
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