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1.
JCI Insight ; 6(5)2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33682798

RESUMO

Parkinson's disease (PD) is a prevalent neurodegenerative disease with no approved disease-modifying therapies. Multiplications, mutations, and single nucleotide polymorphisms in the SNCA gene, encoding α-synuclein (aSyn) protein, either cause or increase risk for PD. Intracellular accumulations of aSyn are pathological hallmarks of PD. Taken together, reduction of aSyn production may provide a disease-modifying therapy for PD. We show that antisense oligonucleotides (ASOs) reduce production of aSyn in rodent preformed fibril (PFF) models of PD. Reduced aSyn production leads to prevention and removal of established aSyn pathology and prevents dopaminergic cell dysfunction. In addition, we address the translational potential of the approach through characterization of human SNCA-targeting ASOs that efficiently suppress the human SNCA transcript in vivo. We demonstrate broad activity and distribution of the human SNCA ASOs throughout the nonhuman primate brain and a corresponding decrease in aSyn cerebral spinal fluid (CSF) levels. Taken together, these data suggest that, by inhibiting production of aSyn, it may be possible to reverse established pathology; thus, these data support the development of SNCA ASOs as a potential disease-modifying therapy for PD and related synucleinopathies.


Assuntos
Encéfalo/efeitos dos fármacos , Oligonucleotídeos Antissenso/uso terapêutico , Doença de Parkinson/tratamento farmacológico , alfa-Sinucleína/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Técnicas de Cultura de Células , Líquido Cefalorraquidiano/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos , Feminino , Humanos , Macaca fascicularis , Masculino , Camundongos , Oligonucleotídeos Antissenso/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , alfa-Sinucleína/genética
2.
Vaccine ; 35(25): 3326-3332, 2017 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-28501455

RESUMO

BACKGROUND: In children, the 13 and 10-valent pneumoccocal conjugate vaccines (PCV13/10) are currently approved for the prevention of invasive pneumococcal disease (IPD). Acceptability is a key consideration in the implementation of a vaccine program and it is recognized that health professional's attitudes and opinions towards vaccines are independent predictors of the success of an immunization program. We aimed to survey the beliefs and attitudes for the two available PCVs in health care professionals and immunization experts. FINDINGS: We interviewed 21 members of Canadian immunization committees and/or participants working in frontline healthcare delivery. Overall, participants predominantly preferred PCV-13 over PCV10. For most, AOM should not be taken into considerations in decisions for pneumococcal vaccination programs implementation. AOM was considered an important endpoint of the program but an ineffective measure of program success due to the lack of surveillance for the condition. Recent evidence pertaining to PCV10 cross-protection against 19A did not affect preference but had an impact on perceptions regarding pricing. CONCLUSION: To consider implementing any changes to the current program, most participants would require more evidence regarding PCV10 cross-protection and effectiveness against OM. Decreasing vaccine price was cited as a positive outcome of funding both vaccines.


Assuntos
Atitude do Pessoal de Saúde , Pessoal de Saúde/psicologia , Programas de Imunização/legislação & jurisprudência , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Canadá , Análise Custo-Benefício , Feminino , Humanos , Programas de Imunização/estatística & dados numéricos , Programas de Imunização/provisão & distribuição , Masculino , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/economia , Vacinas Conjugadas/administração & dosagem
3.
Expert Opin Drug Deliv ; 13(7): 987-98, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27097309

RESUMO

INTRODUCTION: Tumor cells utilize many different mechanisms to desensitize themselves to the cytotoxic effects of drugs, but it has recently been recognized that alterations in epigenetic control of gene expression underly many of them. As master regulators of gene expression, microRNAs (miRNAs) present a promising therapeutic strategy for the reversal of epigenetic changes that lead to drug resistance phenotypes in tumor cells. AREAS COVERED: Effects of epigenetic changes on drug resistance in a variety of solid tumors are discussed. Specific miRNAs that are involved with the regulation of epigenetic machinery are highlighted. Further, we consider how delivery of miRNA or antagomirs may be utilized to resensitize drug-resistant tumor cells. EXPERT OPINION: Reversal of epigenetically controlled tumor drug resistance mechanisms via miRNA delivery presents a novel strategy for enhancing the efficacy of chemotherapeutics. Further, the ability to target delivery of miRNAs may provide the opportunity to go beyond reversal of resistance to hyper-sensitization of tumor cells to the cytotoxic effects of drugs. However, understanding of the role of miRNA in epigenetic regulation is still in its early stages and further research is critical for potential utility in improving therapeutic efficacy in cancer patients.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/genética , Neoplasias/tratamento farmacológico , Epigênese Genética , Humanos , Neoplasias/patologia
4.
Intern Emerg Med ; 11(6): 843-52, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26892405

RESUMO

The skill of delivering bad news is difficult to teach and evaluate. Residents may practice in simulated settings; however, this may not translate to confidence or competence during real experiences. We investigated the acceptability and feasibility of social workers as evaluators of residents' delivery of bad news during patient encounters, and assessed the attitudes of both groups regarding this process. From August 2013 to June 2014, emergency medicine residents completed self-assessments after delivering bad news. Social workers completed evaluations after observing these conversations. The Assessment tools were designed by modifying the global Breaking Bad News Assessment Scale. Residents and social workers completed post-study surveys. 37 evaluations were received, 20 completed by social workers and 17 resident self-evaluations. Social workers reported discussing plans with residents prior to conversations 90 % of the time (18/20, 95 % CI 64.5, 97.8). Social workers who had previously observed the resident delivering bad news reported that the resident was more skilled on subsequent encounters 90 % of the time (95 % CI 42.2, 99). Both social workers and residents felt that prior training or experience was important. First-year residents valued advice from social workers less than advice from attending physicians, whereas more experienced residents perceived advice from social workers to be equivalent with that of attending physicians (40 versus 2.9 %, p = 0.002). Social worker assessment of residents' abilities to deliver bad news is feasible and acceptable to both groups. This formalized self-assessment and evaluation process highlights the importance of social workers' involvement in delivery of bad news, and the teaching of this skill. This method may also be used as direct-observation for resident milestone assessment.


Assuntos
Comunicação , Medicina de Emergência/métodos , Internato e Residência , Relações Médico-Paciente , Assistentes Sociais/psicologia , Adulto , Idoso , Feminino , Humanos , Relações Interprofissionais , Masculino , Pessoa de Meia-Idade , Autoavaliação (Psicologia) , Inquéritos e Questionários , Recursos Humanos
5.
Biotechnol Prog ; 32(1): 235-41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26588060

RESUMO

The serum half-life, biological activity, and solubility of many recombinant glycoproteins depend on their sialylation. Monitoring glycoprotein sialylation during cell culture manufacturing is, therefore, critical to ensure product efficacy and safety. Here a high-throughput method for semi-quantitative fingerprinting of glycoprotein sialylation using capillary isoelectric focusing immunoassay on NanoPro (Protein Simple) platform was developed. The method was specific, sensitive, precise, and robust. It could analyze 2 µL of crude cell culture samples without protein purification, and could automatically analyze from 8 samples in 4 h to 96 samples in 14 h without analyst supervision. Furthermore, its capability to detect various changes in sialylation fingerprints during cell culture manufacturing process was indispensable to ensure process robustness and consistency. Moreover, the changes in the sialylation fingerprints analyzed by this method showed strong correlations with intact mass analysis using liquid chromatography and mass spectrometry.


Assuntos
Glicoproteínas/isolamento & purificação , Focalização Isoelétrica/métodos , Ácido N-Acetilneuramínico/química , Mapeamento de Peptídeos/métodos , Técnicas de Cultura de Células , Cromatografia Líquida , Glicoproteínas/química , Glicosilação , Humanos , Imunoensaio/métodos , Espectrometria de Massas
6.
Bioanalysis ; 7(21): 2801-11, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26541956

RESUMO

AIMS: Neutralizing antibodies can diminish clinical efficacy of IFN-ß in multiple sclerosis patients. Therefore, monitoring immunogenicity was considered critical during clinical development of a second-generation, pegylated IFN-ß product, PEG-IFN-ß-1a. MATERIALS & METHODS: Assays previously used to evaluate immunogenicity of IFN-ß-1a were used to assess PEG-IFN-ß-1a immunogenicity, with modifications to apply current best bioanalytical practices. A separate testing paradigm was used to monitor antibodies to polyethylene glycol. RESULTS & CONCLUSION: Final assay cut points and relevant titer levels were established in-study. Immunogenicity evaluation strategies for second-generation therapeutics should take into consideration current best bioanalytical practices while retaining consistency with legacy assays to facilitate data comparison and interpretation. This study illustrates challenges in assessing immunogenicity of second-generation therapeutics.


Assuntos
Anticorpos Neutralizantes/imunologia , Interferon beta/farmacologia , Esclerose Múltipla/imunologia , Polietilenoglicóis/farmacologia , Ensaios Clínicos Fase III como Assunto , Método Duplo-Cego , Humanos , Interferon beta/imunologia , Estudos Multicêntricos como Assunto , Esclerose Múltipla/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
J Clin Virol ; 57(2): 141-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23465394

RESUMO

BACKGROUND: JC virus (JCV) infection is a prerequisite for development of progressive multifocal leukoencephalopathy (PML). The development and validation of a two-step enzyme-linked immunosorbent assay (ELISA) that detects JCV antibodies in human serum or plasma and its clinical utility for stratification of PML risk have been described. OBJECTIVE: To develop a second-generation JCV antibody ELISA kit with improved assay performance characteristics. STUDY DESIGN: The assay design was optimized by pre-coating the JC virus-like particles (VLP) on microtiter plates. Assay cut-points were statistically established using sera from >1300 multiple sclerosis patients from natalizumab clinical studies. The assay was analytically validated and then used to determine the presence of JCV antibodies in both treatment-naïve and natalizumab-treated MS patients, as well as in natalizumab-treated PML patients. RESULTS: An improved assay for detection of JCV antibodies in human serum and plasma was developed. Key enhancements included improved delineation and reproducibility of low JCV antibody responses and assay ease of use. The assay was validated, demonstrating good agreement with the original two-step JCV antibody ELISA, and similar seroprevalence of 50%-60%. Samples from 63 natalizumab-treated PML patients collected 6-180 months prior to PML diagnosis tested JCV antibody positive. One patient tested JCV antibody negative 15 months prior to PML diagnosis but JCV antibody positive 2 months prior to PML diagnosis. CONCLUSIONS: The validated second-generation JCV antibody ELISA offers improved assay design as a kit and enhanced performance characteristics that advance routine clinical use of the assay as a PML risk stratification tool.


Assuntos
Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Vírus JC/imunologia , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Anticorpos Monoclonais Humanizados/uso terapêutico , Feminino , Humanos , Leucoencefalopatia Multifocal Progressiva/tratamento farmacológico , Leucoencefalopatia Multifocal Progressiva/imunologia , Leucoencefalopatia Multifocal Progressiva/virologia , Masculino , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/imunologia , Esclerose Múltipla/virologia , Natalizumab , Reprodutibilidade dos Testes , Fatores de Risco
8.
J Clin Virol ; 53(1): 65-71, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22104399

RESUMO

BACKGROUND: JC virus (JCV) infection is a prerequisite for development of progressive multifocal leukoencephalopathy (PML). We previously described the development of a novel, two-step enzyme-linked immunosorbent assay (ELISA) that detects anti-JCV antibodies in human serum or plasma, and the potential clinical utility of anti-JCV antibody status for PML risk stratification. OBJECTIVES: To validate the anti-JCV antibody ELISA at multiple clinical laboratories in order to demonstrate the robustness of the method. STUDY DESIGN: Analytical validation of the ELISA was performed at four laboratories by evaluation of intra- and inter-assay precision, analytical specificity and sensitivity, matrix interference, robustness, sample and reagent stability. RESULTS: Analytical validation demonstrated that the assay is sensitive, specific, and precise. The assay sensitivity was estimated at 1.7ng/mL using a humanized anti-JCV monoclonal antibody control. The sensitivity to detect JCV infection was estimated to be 97.5%. The specificity of the assay to discriminate JCV-specific antibodies from antibodies directed to BK virus, a related polyomavirus, was also demonstrated. The inter- and intra-assay precision was ≤6.0% and 9.8% for the screening step and 2.6% and 11.3% for the confirmation step. Results obtained for plasma and serum were highly congruent, and assay robustness was demonstrated by the highly concordant results generated by four laboratories testing a common panel of 100 blinded samples. CONCLUSIONS: The novel, two-step ELISA to detect anti-JCV antibodies in human serum and plasma is robust, and assay performance is consistent and reproducible in multiple laboratories, making it suitable to support testing for global clinical studies.


Assuntos
Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Vírus JC/imunologia , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Antígenos Virais/imunologia , Reações Cruzadas , Humanos , Leucoencefalopatia Multifocal Progressiva/sangue , Leucoencefalopatia Multifocal Progressiva/imunologia , Leucoencefalopatia Multifocal Progressiva/virologia , Estabilidade Proteica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Ann Neurol ; 68(3): 295-303, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20737510

RESUMO

OBJECTIVE: A study was undertaken to establish an enzyme-linked immunosorbent assay (ELISA) to detect JC virus (JCV)-specific antibodies in multiple sclerosis (MS) patients, and to evaluate its potential utility for identifying patients at higher or lower risk (ie, risk stratification) of developing progressive multifocal leukoencephalopathy (PML). METHODS: A 2-step assay for detecting and confirming the presence of anti-JCV antibodies in human serum and plasma was developed and demonstrated to be both sensitive and specific. ELISA cutpoints were statistically established using sera from >800 MS patients from natalizumab clinical studies. Subsequently, this assay was used to determine the presence of anti-JCV antibodies in natalizumab-treated PML patients where serum samples were collected 16-180 months prior to the diagnosis of PML. RESULTS: In our evaluation of natalizumab-treated MS patients, 53.6% tested positive for anti-JCV antibodies, with a 95% confidence interval of 49.9 to 57.3%. The false-negative rate of the ELISA was calculated to be approximately 2.5%, with an upper 1-sided confidence limit of 4.4%. Notably, we observed anti-JCV antibodies in all 17 available pre-PML sera samples, which was significantly different from the 53.6% seropositivity observed in the overall MS study population (p < 0.0001). INTERPRETATION: This 2-step assay provides a means to classify MS patients as having detectable or not detectable levels of anti-JCV antibodies. The finding that all 17 of the pre-PML samples that were available tested seropositive, and none tested seronegative, warrants further research on the clinical utility of the anti-JCV antibody assay as a potential tool for stratifying MS patients for higher or lower risk of developing PML.


Assuntos
Anticorpos Anti-Idiotípicos/uso terapêutico , Vírus JC/imunologia , Leucoencefalopatia Multifocal Progressiva , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , DNA Viral/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Leucoencefalopatia Multifocal Progressiva/imunologia , Leucoencefalopatia Multifocal Progressiva/terapia , Natalizumab , Fatores de Risco , Carga Viral/métodos
10.
FASEB J ; 19(9): 1166-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15901671

RESUMO

Chemically induced birth defects are an important public health and human problem. Here we use Xenopus and zebrafish as models to investigate the mechanism of action of a well-known teratogen, valproic acid (VPA). VPA is a drug used in treatment of epilepsy and bipolar disorder but causes spina bifida if taken during pregnancy. VPA has several biochemical activities, including inhibition of histone deacetylases (HDACs). To investigate the mechanism of action of VPA, we compared its effects in Xenopus and zebrafish embryos with those of known HDAC inhibitors and noninhibitory VPA analogs. We found that VPA and other HDAC inhibitors cause very similar and characteristic developmental defects whereas VPA analogs with poor inhibitory activity in vivo have little teratogenic effect. Unbiased microarray analysis revealed that the effects of VPA and trichostatin A (TSA), a structurally unrelated HDAC inhibitor, are strikingly concordant. The concordance is apparent both by en masse correlation of fold-changes and by detailed similarity of dose-response profiles of individual genes. Together, the results demonstrate that the teratogenic effects of VPA are very likely mediated specifically by inhibition of HDACs.


Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Anticonvulsivantes/toxicidade , Inibidores Enzimáticos/toxicidade , Inibidores de Histona Desacetilases , Ácidos Hidroxâmicos/toxicidade , Ácido Valproico/toxicidade , Animais , Feminino , Perfilação da Expressão Gênica , Especificidade da Espécie , Disrafismo Espinal/induzido quimicamente , Transcrição Gênica/efeitos dos fármacos , Xenopus , Peixe-Zebra/embriologia
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