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1.
JAMA Cardiol ; 2021 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-33993205

RESUMO

IMPORTANCE: In patients treated with ω-3 fatty acids, it remains uncertain whether achieved levels of eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) are associated with cardiovascular outcomes. OBJECTIVE: To determine the association between plasma levels of EPA and DHA and cardiovascular outcomes in a trial of ω-3 fatty acids compared with corn oil placebo. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, multicenter trial enrolled patients at high cardiovascular risk with elevated triglyceride levels and low levels of high-density lipoprotein cholesterol at 675 centers (enrollment from October 30, 2014, to June 14, 2017; study termination January 8, 2020; last visit May 14, 2020). INTERVENTIONS: Participants were randomized to receive 4 g daily of ω-3 carboxylic acid (CA) or an inert comparator, corn oil. MAIN OUTCOMES AND MEASURES: The primary prespecified end point was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina requiring hospitalization. The primary outcome measure was the hazard ratio, adjusted for baseline characteristics, for patients treated with the ω-3 CA compared with corn oil for the top tertile of achieved EPA and DHA plasma levels 12 months after randomization. RESULTS: Of the 13 078 total participants, 6539 (50%) were randomized to receive ω-3 CA and 6539 (50%) randomized to corn oil. ω-3 Fatty acid levels were available at both baseline and 12 months after randomization in 10 382 participants (5175 ω-3 CA patients [49.8%] and 5207 corn oil-treated patients [50.2%]; mean [SD] age, 62.5 [8.9] years, 3588 [34.6%] were women, 9025 [86.9%] were White, and 7285 [70.2%] had type 2 diabetes). The median plasma levels at 12 months in ω-3 CA patients were 89 µg/mL (interquartile range [IQR], 46-131 µg/mL) for EPA and 91 µg/mL (IQR, 71-114 µg/mL) for DHA with top tertile levels of 151 µg/mL (IQR, 132-181 µg/mL) and 118 µg/mL (IQR, 102-143 µg/mL), respectively. Compared with corn oil, the adjusted hazard ratios for the highest tertile of achieved plasma levels were 0.98 (95% CI, 0.83-1.16; P = .81) for EPA, and 1.02 (95% CI, 0.86-1.20; P = .85 for DHA. Sensitivity analyses based on changes in plasma and red blood cell levels of EPA and DHA and primary and secondary prevention subgroups showed similar results. CONCLUSIONS AND RELEVANCE: Among patients treated with ω-3 CA, the highest achieved tertiles of EPA and DHA were associated with neither benefit nor harm in patients at high cardiovascular risk. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02104817.

2.
Neurology ; 89(8): 837-844, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28733335

RESUMO

OBJECTIVE: To provide a comprehensive description of motor speech function in behavioral variant frontotemporal dementia (bvFTD). METHODS: Forty-eight individuals (24 bvFTD and 24 age- and sex-matched healthy controls) provided speech samples. These varied in complexity and thus cognitive demand. Their language was assessed using the Progressive Aphasia Language Scale and verbal fluency tasks. Speech was analyzed perceptually to describe the nature of deficits and acoustically to quantify differences between patients with bvFTD and healthy controls. Cortical thickness and subcortical volume derived from MRI scans were correlated with speech outcomes in patients with bvFTD. RESULTS: Speech of affected individuals was significantly different from that of healthy controls. The speech signature of patients with bvFTD is characterized by a reduced rate (75%) and accuracy (65%) on alternating syllable production tasks, and prosodic deficits including reduced speech rate (45%), prolonged intervals (54%), and use of short phrases (41%). Groups differed on acoustic measures derived from the reading, unprepared monologue, and diadochokinetic tasks but not the days of the week or sustained vowel tasks. Variability of silence length was associated with cortical thickness of the inferior frontal gyrus and insula and speech rate with the precentral gyrus. CONCLUSIONS: One in 8 patients presented with moderate speech timing deficits with a further two-thirds rated as mild or subclinical. Subtle but measurable deficits in prosody are common in bvFTD and should be considered during disease management. Language function correlated with speech timing measures derived from the unprepared monologue only.


Assuntos
Demência Frontotemporal/fisiopatologia , Demência Frontotemporal/psicologia , Destreza Motora , Fala , Córtex Cerebral/diagnóstico por imagem , Feminino , Demência Frontotemporal/diagnóstico por imagem , Humanos , Teste de Tolerância a Lactose , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Fenótipo , Medida da Produção da Fala
3.
J Speech Lang Hear Res ; 60(4): 897-911, 2017 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-28289749

RESUMO

Purpose: Our purpose was to create a comprehensive review of speech impairment in frontotemporal dementia (FTD), primary progressive aphasia (PPA), and progressive apraxia of speech in order to identify the most effective measures for diagnosis and monitoring, and to elucidate associations between speech and neuroimaging. Method: Speech and neuroimaging data described in studies of FTD and PPA were systematically reviewed. A meta-analysis was conducted for speech measures that were used consistently in multiple studies. Results: The methods and nomenclature used to describe speech in these disorders varied between studies. Our meta-analysis identified 3 speech measures which differentiate variants or healthy control-group participants (e.g., nonfluent and logopenic variants of PPA from all other groups, behavioral-variant FTD from a control group). Deficits within the frontal-lobe speech networks are linked to motor speech profiles of the nonfluent variant of PPA and progressive apraxia of speech. Motor speech impairment is rarely reported in semantic and logopenic variants of PPA. Limited data are available on motor speech impairment in the behavioral variant of FTD. Conclusions: Our review identified several measures of speech which may assist with diagnosis and classification, and consolidated the brain-behavior associations relating to speech in FTD, PPA, and progressive apraxia of speech.


Assuntos
Afasia Primária Progressiva , Apraxias , Demência Frontotemporal , Fala , Afasia Primária Progressiva/diagnóstico por imagem , Afasia Primária Progressiva/fisiopatologia , Apraxias/diagnóstico por imagem , Apraxias/fisiopatologia , Encéfalo/diagnóstico por imagem , Demência Frontotemporal/diagnóstico por imagem , Demência Frontotemporal/fisiopatologia , Humanos , Destreza Motora , Fenótipo
4.
Clin Linguist Phon ; 29(1): 46-58, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25207996

RESUMO

Perceptual speech research in Friedreich ataxia (FRDA) has identified altered nasality as a key component of the dysarthria profile, however the incidence and severity of abnormal nasality remains unknown. Utilizing objective and perceptual methods, data on the relationship between resonance, disease duration, severity, age of onset and genetic profiles were collated. Thirty-seven participants with FRDA and 24 healthy controls provided contemporaneous speech samples for perceptual analysis, and single word samples for acoustic analysis. A subset of participants (eight participants with FRDA and eight controls) underwent nasometry assessment. Twenty-seven participants with FRDA presented with hypernasality and five with hyponasality on perceptual assessment. Acoustic analysis revealed participants with FRDA had greater nasality than controls (p < 0.05). Perceptual ratings of hypernasality correlated with GAA2 repeat length (ρ = 0.37, p = 0.03). Findings highlight the variability of nasality in FRDA, potentially reflecting variation in the neuropathological profile. Data also suggest the influence of genetic profiles on nasality.


Assuntos
Transtornos da Articulação/diagnóstico , Disartria/diagnóstico , Ataxia de Friedreich/diagnóstico , Acústica da Fala , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Espectrografia do Som , Percepção da Fala , Medida da Produção da Fala
5.
Cochrane Database Syst Rev ; (10): CD008953, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25348587

RESUMO

BACKGROUND: Hereditary ataxia syndromes can result in significant speech impairment, a symptom thought to be responsive to treatment. The type of speech impairment most commonly reported in hereditary ataxias is dysarthria. Dysarthria is a collective term referring to a group of movement disorders affecting the muscular control of speech. Dysarthria affects the ability of individuals to communicate and to participate in society. This in turn reduces quality of life. Given the harmful impact of speech disorder on a person's functioning, treatment of speech impairment in these conditions is important and evidence-based interventions are needed. OBJECTIVES: To assess the effects of interventions for speech disorder in adults and children with Friedreich ataxia and other hereditary ataxias. SEARCH METHODS: On 14 October 2013, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, CINAHL Plus, PsycINFO, Education Resources Information Center (ERIC), Linguistics and Language Behavior Abstracts (LLBA), Dissertation Abstracts and trials registries. We checked all references in the identified trials to identify any additional published data. SELECTION CRITERIA: We considered for inclusion randomised controlled trials (RCTs) or quasi-RCTs that compared treatments for hereditary ataxias with no treatment, placebo or another treatment or combination of treatments, where investigators measured speech production. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion, extracted data and assessed the risk of bias of included studies using the standard methodological procedures expected by The Cochrane Collaboration. The review authors collected information on adverse effects from included studies. We did not conduct a meta-analysis as no two studies utilised the same assessment procedures within the same treatment. MAIN RESULTS: Fourteen clinical trials, involving 721 participants, met the criteria for inclusion in the review. Thirteen studies compared a pharmaceutical treatment with placebo (or a low dose of the intervention), in heterogenous groups of degenerative cerebellar ataxias. Three compounds were studied in two trials each: a levorotatory form of 5-hydroxytryptophan (L-5HT), idebenone and thyrotropin-releasing hormone tartrate (TRH-T); each of the other compounds (riluzole, varenicline, buspirone, betamethasone, coenzyme Q10 with vitamin E, α-tocopheryl quinone and erythropoietin) were studied in one trial. The 14th trial, involving a mixed group of participants with spinocerebellar ataxia, compared the effectiveness of nonspecific physiotherapy and occupational therapy within an inpatient hospital setting to no treatment. No studies utilised traditional speech therapies. We defined the primary outcome measure in this review as the percentage change (improvement) in overall speech production immediately following completion of the intervention or later, measured by any validated speech assessment tool. None of the trials included speech as a primary outcome or examined speech using any validated speech assessment tool. Eleven studies reported speech outcomes derived from a subscale embedded within disease rating scales. The remaining three studies used alternative assessments to measure speech, including mean time to produce a standard sentence, a subjective rating of speech on a 14-point analogue scale, patient-reported assessment of the impact of dysarthria on activities of daily living and acoustic measures of syllable length. One study measured speech both subjectively as part of a disease rating scale and with further measures of speech timing. Three studies utilised the Short Form-36 Health Survey (SF-36) and one used the Child Health Questionnaire as measures of general quality of life. A further study utilised the Functional Independence Measure to assess functional health.Five studies reported statistically significant improvement on an overall disease rating scale in which a speech subscale was included. Only three of those studies provided specific data on speech performance; all were comparisons with placebo. Improvements in overall disease severity were observed with α-tocopheryl quinone; however, no significant changes were found on the speech subscale in a group of individuals with Friedreich ataxia. A statistically significant improvement in speech according to a speech disorders subscale was observed with betamethasone. Riluzole was found to have a statistically significant effect on speech in a group of participants with mixed hereditary, sporadic and unknown origin ataxias. No significant differences were observed between treatment and placebo in any other pharmaceutical study. A statistically significant improvement in functional independence occurred at the end of the treatment period in the rehabilitation study compared to the delayed treatment group but these effects were not present 12 to 24 weeks after treatment. Of the four studies that assessed quality of life, none found a significant effect. A variety of minor adverse events were reported for the 13 pharmaceutical therapies, including gastrointestinal side effects and nausea. Serious adverse effects were reported in two participants in one of the L-5HT trials (participants discontinued due to gastrointestinal effects), and in four participants (three taking idebenone, one taking placebo) in the idebenone studies. Serious adverse events with idebenone were gastrointestinal side effects and, in people with a previous history of these events, chest pain and idiopathic thrombocytopenic purpura. The rehabilitation study did not report any adverse events.We considered six studies to be at high risk of bias in some respect. We suspected inadequate blinding of participants or assessors in four studies and poor randomisation in a further two studies. There was a high risk of reporting bias in two studies and attrition bias in four studies. Only one study had a low risk of bias across all criteria. Taken together with other limitations of the studies relating to the validity of the measurement scales used, we downgraded the quality of the evidence for many of the outcomes to low or very low. AUTHORS' CONCLUSIONS: There is insufficient and low or very low quality evidence from either RCTs or observational studies to determine the effectiveness of any treatment for speech disorder in any of the hereditary ataxia syndromes.


Assuntos
Ataxia de Friedreich/terapia , Distúrbios da Fala/terapia , Degenerações Espinocerebelares/terapia , Ataxia de Friedreich/complicações , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fala , Distúrbios da Fala/tratamento farmacológico , Distúrbios da Fala/etiologia , Degenerações Espinocerebelares/complicações
6.
Artigo em Inglês | MEDLINE | ID: mdl-21576756

RESUMO

In this paper, we investigate the problem of reverse engineering the topology of gene regulatory networks from temporal gene expression data. We adopt a computational intelligence approach comprising swarm intelligence techniques, namely particle swarm optimization (PSO) and ant colony optimization (ACO). In addition, the recurrent neural network (RNN) formalism is employed for modeling the dynamical behavior of gene regulatory systems. More specifically, ACO is used for searching the discrete space of network architectures and PSO for searching the corresponding continuous space of RNN model parameters. We propose a novel solution construction process in the context of ACO for generating biologically plausible candidate architectures. The objective is to concentrate the search effort into areas of the structure space that contain architectures which are feasible in terms of their topological resemblance to real-world networks. The proposed framework is initially applied to the reconstruction of a small artificial network that has previously been studied in the context of gene network reverse engineering. Subsequently, we consider an artificial data set with added noise for reconstructing a subnetwork of the genetic interaction network of S. cerevisiae (yeast). Finally, the framework is applied to a real-world data set for reverse engineering the SOS response system of the bacterium Escherichia coli. Results demonstrate the relative advantage of utilizing problem-specific knowledge regarding biologically plausible structural properties of gene networks over conducting a problem-agnostic search in the vast space of network architectures.


Assuntos
Algoritmos , Biologia Computacional/métodos , Redes Reguladoras de Genes/genética , Escherichia coli/genética , Expressão Gênica/genética , Perfilação da Expressão Gênica , Modelos Genéticos , Saccharomyces cerevisiae/genética
7.
J Clin Pathol ; 63(11): 1012-20, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20924094

RESUMO

BACKGROUND: Chemotherapy benefits relatively few patients with cutaneous melanoma. The assessment of tumour chemosensitivity by the ATP-based tumour chemosensitivity assay (ATP-TCA) has shown strong correlation with outcome in cutaneous melanoma, but requires fresh tissue and dedicated laboratory facilities. AIM: To examine whether the results of the ATP-TCA correlate with the expression of genes known to be involved in resistance to chemotherapy, based on the hypothesis that the molecular basis of chemosensitivity lies within known drug resistance mechanisms. METHOD: The chemosensitivity of 47 cutaneous melanomas was assessed using the ATP-TCA and correlated with quantitative expression of 93 resistance genes measured by quantitative reverse transcriptase PCR (qRT-PCR) in a Taqman Array after extraction of total RNA from formalin-fixed paraffin-embedded tissue. RESULTS: Drugs susceptible to particular resistance mechanisms showed good correlation with genes linked to these mechanisms using signatures of up to 17 genes. Comparison of these signatures for DTIC, treosulfan and cisplatin showed several genes in common. HSP70, at least one human epidermal growth factor receptor, genes involved in apoptosis (IAP2, PTEN) and DNA repair (ERCC1, XPA, XRCC1, XRCC6) were present for these agents, as well as genes involved in the regulation of proliferation (Ki67, p21, p27). The combinations tested included genes represented in the single agent signatures. CONCLUSIONS: These data suggest that melanoma chemosensitivity is influenced by known resistance mechanisms, including susceptibility to apoptosis. Use of a candidate gene approach may increase understanding of the mechanisms underlying chemosensitivity to drugs active against melanoma and provide signatures with predictive value.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Melanoma/genética , Melanoma/secundário , Neoplasias Cutâneas/genética , Trifosfato de Adenosina/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , DNA de Neoplasias/genética , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Perfilação da Expressão Gênica/métodos , Genes Neoplásicos , Humanos , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
8.
BMC Cancer ; 9: 300, 2009 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-19712441

RESUMO

BACKGROUND: NSCLC exhibits considerable heterogeneity in its sensitivity to chemotherapy and similar heterogeneity is noted in vitro in a variety of model systems. This study has tested the hypothesis that the molecular basis of the observed in vitro chemosensitivity of NSCLC lies within the known resistance mechanisms inherent to these patients' tumors. METHODS: The chemosensitivity of a series of 49 NSCLC tumors was assessed using the ATP-based tumor chemosensitivity assay (ATP-TCA) and compared with quantitative expression of resistance genes measured by RT-PCR in a Taqman Array following extraction of RNA from formalin-fixed paraffin-embedded (FFPE) tissue. RESULTS: There was considerable heterogeneity between tumors within the ATP-TCA, and while this showed no direct correlation with individual gene expression, there was strong correlation of multi-gene signatures for many of the single agents and combinations tested. For instance, docetaxel activity showed some dependence on the expression of drug pumps, while cisplatin activity showed some dependence on DNA repair enzyme expression. Activity of both drugs was influenced more strongly still by the expression of anti- and pro-apoptotic genes by the tumor for both docetaxel and cisplatin. The doublet combinations of cisplatin with gemcitabine and cisplatin with docetaxel showed gene expression signatures incorporating resistance mechanisms for both agents. CONCLUSION: Genes predicted to be involved in known mechanisms drug sensitivity and resistance correlate well with in vitro chemosensitivity and may allow the definition of predictive signatures to guide individualized chemotherapy in lung cancer.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Pulmonares/genética , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Masculino , Pessoa de Meia-Idade
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