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1.
Psychol Med ; 48(5): 751-764, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28933314

RESUMO

BACKGROUND: Cognitive remediation (CR) training has emerged as a promising approach to improving cognitive deficits in schizophrenia and related psychosis. The limited availability of psychological services for psychosis is a major barrier to accessing this intervention however. This study investigated the effectiveness of a low support, remotely accessible, computerised working memory (WM) training programme in patients with psychosis. METHODS: Ninety patients were enrolled into a single blind randomised controlled trial of CR. Effectiveness of the intervention was assessed in terms of neuropsychological performance, social and occupational function, and functional MRI 2 weeks post-intervention, with neuropsychological and social function again assessed 3-6 months post-treatment. RESULTS: Patients who completed the intervention showed significant gains in both neuropsychological function (measured using both untrained WM and episodic task performance, and a measure of performance IQ), and social function at both 2-week follow-up and 3-6-month follow-up timepoints. Furthermore, patients who completed MRI scanning showed improved resting state functional connectivity relative to patients in the placebo condition. CONCLUSIONS: CR training has already been shown to improve cognitive and social function in patient with psychosis. This study demonstrates that, at least for some chronic but stable outpatients, a low support treatment was associated with gains that were comparable with those reported for CR delivered entirely on a 1:1 basis. We conclude that CR has potential to be delivered even in services in which psychological supports for patients with psychosis are limited.


Assuntos
Disfunção Cognitiva/reabilitação , Remediação Cognitiva/métodos , Memória de Curto Prazo/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Transtornos Psicóticos/reabilitação , Esquizofrenia/reabilitação , Telemedicina/métodos , Adulto , Disfunção Cognitiva/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/complicações , Esquizofrenia/complicações , Método Simples-Cego , Terapia Assistida por Computador/métodos
2.
J Evol Biol ; 28(8): 1489-501, 2015 08.
Artigo em Inglês | MEDLINE | ID: mdl-26079367

RESUMO

Dispersal ability will largely determine whether species track their climatic niches during climate change, a process especially important for populations at contracting (low-latitude/low-elevation) range limits that otherwise risk extinction. We investigate whether dispersal evolution at contracting range limits is facilitated by two processes that potentially enable edge populations to experience and adjust to the effects of climate deterioration before they cause extinction: (i) climate-induced fitness declines towards range limits and (ii) local adaptation to a shifting climate gradient. We simulate a species distributed continuously along a temperature gradient using a spatially explicit, individual-based model. We compare range-wide dispersal evolution during climate stability vs. directional climate change, with uniform fitness vs. fitness that declines towards range limits (RLs), and for a single climate genotype vs. multiple genotypes locally adapted to temperature. During climate stability, dispersal decreased towards RLs when fitness was uniform, but increased when fitness declined towards RLs, due to highly dispersive genotypes maintaining sink populations at RLs, increased kin selection in smaller populations, and an emergent fitness asymmetry that favoured dispersal in low-quality habitat. However, this initial dispersal advantage at low-fitness RLs did not facilitate climate tracking, as it was outweighed by an increased probability of extinction. Locally adapted genotypes benefited from staying close to their climate optima; this selected against dispersal under stable climates but for increased dispersal throughout shifting ranges, compared to cases without local adaptation. Dispersal increased at expanding RLs in most scenarios, but only increased at the range centre and contracting RLs given local adaptation to climate.


Assuntos
Adaptação Fisiológica , Ecossistema , Aptidão Genética , Modelos Biológicos , Evolução Biológica , Mudança Climática , Genótipo , Temperatura
3.
Mol Psychiatry ; 19(4): 452-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23568192

RESUMO

Bipolar disorder (BD) is a polygenic disorder that shares substantial genetic risk factors with major depressive disorder (MDD). Genetic analyses have reported numerous BD susceptibility genes, while some variants, such as single-nucleotide polymorphisms (SNPs) in CACNA1C have been successfully replicated, many others have not and subsequently their effects on the intermediate phenotypes cannot be verified. Here, we studied the MDD-related gene CREB1 in a set of independent BD sample groups of European ancestry (a total of 64,888 subjects) and identified multiple SNPs significantly associated with BD (the most significant being SNP rs6785[A], P=6.32 × 10(-5), odds ratio (OR)=1.090). Risk SNPs were then subjected to further analyses in healthy Europeans for intermediate phenotypes of BD, including hippocampal volume, hippocampal function and cognitive performance. Our results showed that the risk SNPs were significantly associated with hippocampal volume and hippocampal function, with the risk alleles showing a decreased hippocampal volume and diminished activation of the left hippocampus, adding further evidence for their involvement in BD susceptibility. We also found the risk SNPs were strongly associated with CREB1 expression in lymphoblastoid cells (P<0.005) and the prefrontal cortex (P<1.0 × 10(-6)). Remarkably, population genetic analysis indicated that CREB1 displayed striking differences in allele frequencies between continental populations, and the risk alleles were completely absent in East Asian populations. We demonstrated that the regional prevalence of the CREB1 risk alleles in Europeans is likely caused by genetic hitchhiking due to natural selection acting on a nearby gene. Our results suggest that differential population histories due to natural selection on regional populations may lead to genetic heterogeneity of susceptibility to complex diseases, such as BD, and explain inconsistencies in detecting the genetic markers of these diseases among different ethnic populations.


Assuntos
Transtorno Bipolar/etnologia , Transtorno Bipolar/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Regulação da Expressão Gênica/genética , Predisposição Genética para Doença , Hipocampo/patologia , Polimorfismo de Nucleotídeo Único/genética , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Estudos de Casos e Controles , Biologia Computacional , Feminino , Frequência do Gene/genética , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Fenótipo , RNA Mensageiro/metabolismo , População Branca/genética
4.
Psychol Med ; 44(10): 2177-87, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24284030

RESUMO

BACKGROUND: Genetic studies of single gene variants have been criticized as providing a simplistic characterization of the genetic basis of illness risk that ignores the effects of other variants within the same biological pathways. Of candidate biological pathways for schizophrenia (SZ), the cell adhesion molecule (CAM) pathway has repeatedly been linked to both psychosis and neurocognitive dysfunction. Here we tested, using risk allele scores derived from the Schizophrenia Psychiatric Genome-Wide Association Study Consortium (PGC-SCZ), whether alleles within the CAM pathway were correlated with poorer neuropsychological function in patients. METHOD: In total, 424 patients with psychosis were assessed in areas of cognitive ability typically found to be impaired in SZ: intelligence quotient, memory, working memory and attentional control. CAM pathway genes were identified using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Alleles within these genes identified as significantly associated with SZ risk in the PGC-SCZ were then used to calculate a CAM pathway-based polygenic risk allele score for each patient and these scores were tested for association with cognitive ability. RESULTS: Increased CAM pathway polygenic risk scores were significantly associated with poorer performance on measures of memory and attention, explaining 1-3% of variation on these measures. Notably, the most strongly associated single nucleotide polymorphism (SNP) in the CAM pathway (rs9272105 within HLA-DQA1) explained a similar amount of variance in attentional control, but not memory, as the polygenic risk analysis. CONCLUSIONS: These data support a role for the CAM pathway in cognitive function, both at the level of individual SNPs and the wider pathway. In so doing these data highlight the value of pathway-based polygenic risk score studies as well as single gene studies for understanding SZ-associated deficits in cognition.


Assuntos
Moléculas de Adesão Celular/genética , Transtornos Cognitivos/genética , Transtornos Psicóticos/genética , Esquizofrenia/genética , Transdução de Sinais/genética , Adulto , Alelos , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Cadeias alfa de HLA-DQ/genética , Humanos , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Transtornos Psicóticos/complicações , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/complicações , Esquizofrenia/fisiopatologia
5.
Eur Rev Med Pharmacol Sci ; 26(1): 168-182, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35049033

RESUMO

OBJECTIVE: The organophosphate compounds chlorpyrifos (O, O-diethyl O-[3,5,6-trichloro-2-pyridinyl] phosphorothioate, CPF) and phenyl saligenin phosphate (PSP) have been widely implicated in developmental neurotoxicity and neurodegeneration. However, the underlying mechanism remains unclear. Transglutaminase (TG)2 is a calcium ion (Ca2+)-dependent enzyme with an important role in neuronal cell outgrowth and differentiation and in neurotoxin activity and is modulated by organophosphates. MATERIALS AND METHODS: We studied TG2 activity modulation by CPO and PSP during differentiation in C6 glioma cells. We studied the effects of CPO or PSP treatment with or without the TG2 inhibitor Z-DON and identified potential TG2 protein substrates via mass spectrometry. RESULTS: PSP and CPO did not affect cell viability but affected TG2 activity in differentiating cells. Our results indicate that the organophosphate-induced amine incorporation activity of TG2 may have a direct effect on neuronal outgrowth, differentiation, and cell survival by modifying several essential microtubule proteins, including tubulin. Inhibiting TG2 reduced neurite length but not cell survival. CONCLUSIONS: TG2 inhibitors can protect against organophosphate-induced neuropathy and could be used for developing novel therapeutic strategies for treating brain cancer and neurodegenerative disorders.


Assuntos
Proteínas de Ligação ao GTP , Transglutaminases , Animais , Diferenciação Celular , Organofosfatos/farmacologia , Proteína 2 Glutamina gama-Glutamiltransferase , Ratos
6.
Toxicol Appl Pharmacol ; 256(3): 330-6, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21704052

RESUMO

Previous work in our laboratory has shown that sub-lethal concentrations (1-10 µM) of chlorpyrifos (CPF), diazinon (DZ) and diazinon oxon (DZO) inhibit the outgrowth of axon-like neurites in differentiating mouse N2a neuroblastoma cells concomitant with altered levels and/or phosphorylation state of axonal cytoskeleton and growth-associated proteins. The aim of the present work was to determine whether chlorpyrifos oxon (CPO) was capable of inhibiting N2a cell differentiation in a similar manner. Using experimental conditions similar to our previous work, sub-lethal concentrations (1-10 µM) of CPO were found to inhibit N2a cell differentiation. However, unlike previous studies with DZ and DZO, there was a high level of sustained inhibition of acetylcholinesterase (AChE) in CPO treated cells. Impairment of neurite outgrowth was also associated with reduced levels of growth associated protein-43 and neurofilament heavy chain (NFH), and the distribution of NFH in cells stained by indirect immunofluorescence was disrupted. However, in contrast to previous findings for DZO, the absolute level of phosphorylated NFH was unaffected by CPO exposure. Taken together, the findings suggest that sub-lethal concentrations of CPO inhibit axon outgrowth in differentiating N2a cells and that this effect involves reduced levels of two proteins that play key roles in axon outgrowth and maintenance. Although the inhibition of neurite outgrowth is unlikely to involve AChE inhibition directly, further work will help to determine whether the persistent inhibition of AChE by CPO can account for the different effects induced by CPO and DZO on the levels of total and phosphorylated NFH.


Assuntos
Acetilcolinesterase/efeitos dos fármacos , Clorpirifos/farmacologia , Inibidores da Colinesterase/farmacologia , Proteínas do Citoesqueleto/efeitos dos fármacos , Neuritos/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Animais , Western Blotting , Neoplasias Encefálicas/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Clorpirifos/administração & dosagem , Inibidores da Colinesterase/administração & dosagem , Relação Dose-Resposta a Droga , Técnica Indireta de Fluorescência para Anticorpo , Camundongos , Neuritos/fisiologia , Neuroblastoma/metabolismo
7.
J Educ Chang ; 21(3): 393-420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-38624328

RESUMO

This paper analyzes the nature and perceived effects of mid-stakes testing (known as the EQAO) in Ontario, Canada. Ontario's mid-stakes tests were meant to ensure accountability and transparency, and assure system-wide improvement, while avoiding the negative effects and perverse incentives of their high-stakes counterparts. The paper provides new evidence from two projects covering almost a 10-year time-span in 10 of Ontario's 72 school districts. It shows that even though mid-stakes testing is milder in its manifestations and effects than high-stakes testing, concerns remain about the need for and side effects of such testing. The findings concern two periods of Ontario educational reform. In the first period, with a specific focus on improving performance in literacy and mathematics, administrators and special education support staff felt that the assessments raised teachers' expectations and sense of urgency leading to steady improvements in measured achievement, but that there was also evidence of negative effects, especially on paying undue attention to "bubble" students just below the threshold for minimum proficiency. In the second reform period focused on broad excellence, well-being and equity as inclusion, mid-stakes tests were perceived as having more widespread negative effects. These included teaching to the test, cultural bias, avoidance of innovation, dilemmas of whether to include highly vulnerable students in the testing process or not, and emotional ill-being among students and teachers. The paper concludes that Ontario's twentieth century system of large scale, mid-stakes assessment has not kept pace with its twenty first century commitments to deeper learning and stronger well-being.

8.
Environ Sci Process Impacts ; 22(9): 1865-1876, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32794543

RESUMO

Comparison of monitoring data with toxicologically-derived environmental quality standards (EQSs) forms the basis of assessments of the quality status of the water environment. Having established the status quo, the logical next step is to address instances of non-compliance with EQSs by applying remedial measures, including reducing the use or at least the emission of the substances of concern or by taking steps to reduce concentrations already present using technological solutions such as enhanced wastewater treatment. The selection of suitable remedial measures must be a compromise between cost, likely effectiveness and the timescale over which improvements might be acceptable. The decision on overall environmental management has also to take into account the need for demonstrable progress; this might mean that it is preferable to address some more readily achievable goal rather than to attempt to solve a more serious, but ultimately intractable problem. This paper describes the development and application of a generic modelling tool that provides a way of assessing the potential requirements for remedial actions and their likely outcomes over a timescale of up to forty years taking account of sediment partitioning, environmental degradation and biological accumulation. The tool was validated using a detailed UK wastewater treatment works effluent discharge dataset. Examples involving several chemicals that are of current concern are provided. Some substances (e.g. tributyltin, PFOS) are identified as likely to meet EQS values in sediments or biota in a relatively short timescale; others (PAHs, DEHP) appear to represent more intractable problems.


Assuntos
Poluentes Ambientais , Modelos Teóricos , Monitoramento Ambiental , Poluentes Químicos da Água/análise
9.
Toxicol Appl Pharmacol ; 240(2): 159-65, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19647006

RESUMO

In previous work we showed that sub-lethal levels of diazinon inhibited neurite outgrowth in differentiating N2a neuroblastoma cells. Western blotting analysis targeted at proteins involved in axon growth and stress responses, revealed that such exposure led to a reduction in the levels of neurofilament heavy chain, microtubule associated protein 1 B (MAP 1B) and HSP-70. The aim of this study was to apply the approach of 2 dimensional polyacrylamide gel electrophoresis and mass spectrometry to identify novel biomarkers of effect. A number of proteins were found to be up-regulated compared to the control on silver-stained gels. These were classified in to 3 main groups of proteins: cytosolic factors, chaperones and the actin-binding protein cofilin, all of which are involved in cell differentiation, survival or metabolism. The changes observed for cofilin were further confirmed by quantitative Western blotting analysis with anti-actin and anti-cofilin antibodies. Indirect immunofluorescence staining with the same antibodies indicated that the microfilament network was disrupted in diazinon-treated cells. Our data suggest that microfilament organisation is disrupted by diazinon exposure, which may be related to increased cofilin expression.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Inibidores da Colinesterase/toxicidade , Diazinon/toxicidade , Inseticidas/toxicidade , Proteínas do Tecido Nervoso/metabolismo , Neuritos/efeitos dos fármacos , Neuroblastoma/metabolismo , Proteômica , Fatores de Despolimerização de Actina/metabolismo , Animais , Biomarcadores/metabolismo , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Relação Dose-Resposta a Droga , Eletroforese em Gel Bidimensional , Imunofluorescência , Camundongos , Chaperonas Moleculares/metabolismo , Neuritos/metabolismo , Neuritos/patologia , Neuroblastoma/patologia , Proteômica/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
10.
Sci Adv ; 5(2): eaau4403, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30801010

RESUMO

Species interactions have long been predicted to increase in intensity toward the tropics and low elevations because of gradients in climate, productivity, or biodiversity. Despite their importance for understanding global ecological and evolutionary processes, plant-animal interaction gradients are particularly difficult to test systematically across large geographic gradients, and evidence from smaller, disparate studies is inconclusive. By systematically measuring postdispersal seed predation using 6995 standardized seed depots along 18 mountains in the Pacific cordillera, we found that seed predation increases by 17% from the Arctic to the Equator and by 17% from 4000 meters above sea level to sea level. Clines in total predation, likely driven by invertebrates, were consistent across treeline ecotones and within continuous forest and were better explained by climate seasonality than by productivity, biodiversity, or latitude. These results suggest that species interactions play predictably greater ecological and evolutionary roles in tropical, lowland, and other less seasonal ecosystems.


Assuntos
Biodiversidade , Florestas , Invertebrados/fisiologia , Comportamento Predatório/fisiologia , Sementes , Clima Tropical , Animais , Regiões Árticas
12.
Toxicol In Vitro ; 22(5): 1387-91, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18417317

RESUMO

The aim of this work was to assess the toxic effects of the phosphorothionate insecticide chlorpyrifos (CPF) and its major in vivo metabolite chlorpyrifos oxon (CPO) on differentiating rat C6 glioma cells. At sublethal concentrations (1-10 microM), both compounds were able to inhibit the development of extensions from C6 cells induced to differentiate by sodium butyrate. Western blot analysis of C6 cell lysates revealed that 4 h exposure to CPF was associated with decreased levels of the cytoskeletal protein MAP1B compared to controls, whereas the levels of the cytoskeletal proteins tubulin and MAP2c were not significantly affected. Western blot analysis of extracts of cells treated with CPO showed a significant, concentration-dependent decrease in the levels of tubulin after 24 h. MAP-1B levels were also significantly decreased. The above changes were not temporally related to acetylcholinesterase (AChE) inhibition. These results suggest that both CPF and CPO can exert toxic effects directly on glial cell differentiation and that the latter compound has a potent effect on the microtubule network.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Transformação Celular Neoplásica/efeitos dos fármacos , Clorpirifos/análogos & derivados , Glioma/tratamento farmacológico , Inseticidas/toxicidade , Proteínas Associadas aos Microtúbulos/efeitos dos fármacos , Animais , Neoplasias Encefálicas/patologia , Butiratos/farmacologia , Linhagem Celular Tumoral , Clorpirifos/toxicidade , Relação Dose-Resposta a Droga , Glioma/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Ratos , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo
13.
Toxicol In Vitro ; 21(7): 1258-61, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17553660

RESUMO

The aims of this work were to compare the effects of methyl mercury chloride and thimerosal on neurite/process outgrowth and microtubule proteins in differentiating mouse N2a neuroblastoma and rat C6 glioma cells. Exposure for 4h to sublethal concentrations of both compounds inhibited neurite outgrowth to a similar extent in both cells lines compared to controls. In the case of N2a cells, this inhibitory effect by both compounds was associated with a fall in the reactivity of western blots of cell extracts with monoclonal antibody T1A2, which recognises C-terminally tyrosinated alpha-tubulin. By contrast, reactivity with monoclonal antibody B512 (which recognises total alpha-tubulin) was unaffected at the same time point. These findings suggest that decreased tubulin tyrosination represents a neuron-specific early marker of mercury toxicity associated with impaired neurite outgrowth.


Assuntos
Compostos de Metilmercúrio/toxicidade , Timerosal/toxicidade , Tubulina (Proteína)/efeitos dos fármacos , Tirosina/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Biomarcadores , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Glioma/metabolismo , Camundongos , Proteínas dos Microtúbulos/efeitos dos fármacos , Proteínas dos Microtúbulos/metabolismo , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neuroblastoma/metabolismo , Ratos , Tubulina (Proteína)/metabolismo
14.
J Photochem Photobiol B ; 89(2-3): 110-6, 2007 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-17977740

RESUMO

Ultraviolet A (UVA) light (315-400 nm) is ubiquitously found in our environment and constitutes about 95% of the total solar UV; all UVC and most UVB being absorbed by the stratospheric ozone layer. Compared with UVB and C, UVA does not show any direct effect on biological systems. Indirect effects of UVA, however, have been recognised overwhelmingly and this includes photosensitization of biological and non-biological compounds and production of free radicals many of which include oxygen and are hence known as reactive oxygen species or ROS. Several types of free radicals have been identified although their impacts on various macro- and micro-biomolecules are yet to be fully elucidated. beta-Phenylpyruvic acid is ubiquitously found in eukaryotic cells as a metabolite of phenylalanine, which is subsequently converted to phenyllactate and/or to 2-hydroxyphenylacetate and mandelate. In patients suffering from phenylketonuria the hydroxylation of phenylalanine to tyrosine is defective due to lack of phenylalanine hydroxylase. These result in accumulation and excretion of this compound in the urine. Here we present evidence that photolysis of beta-phenylpyruvic acid by a skin tanning lamp, emitting 99% UVA (315-400 nm) and 1% UVB (290-315 nm) generates carboxyl radicals (CO(2)(*)) and also possibly causes direct electron transfer (or type 1) reactions. Electron paramagnetic resonance was used to detect the free radicals. To determine the biological effects of this photolytic reaction, T7 was exposed to these photolytic reactive agents and found to lead to high levels of phage inactivation. Damage to DNA and/or components such as tail fibre proteins may be involved in T7 inactivation. In addition, our unpublished data suggest that certain phenylketonuria cell lines are more sensitive to PPA+NUV, lending importance to photolytic studies of this agent.


Assuntos
Dano ao DNA , Radicais Livres/síntese química , Ácidos Fenilpirúvicos/efeitos da radiação , Espécies Reativas de Oxigênio/síntese química , Raios Ultravioleta , Bacteriófago T7/efeitos dos fármacos , Ensaio Cometa , Espectroscopia de Ressonância de Spin Eletrônica , Fotólise
15.
QJM ; 99(2): 81-7, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16410286

RESUMO

BACKGROUND: Management of patients with an acute coronary syndrome (ACS) requires accurate risk stratification to guide appropriate therapy. AIM: To assess the utility of the TIMI risk score in stratifying patients with possible ACS in routine clinical practice. DESIGN: Prospective observational study. METHODS: We recruited 869 consecutive patients with a diagnosis of possible ACS attending the acute medical receiving unit of a district general hospital. The main outcome measures were recurrent myocardial infarction, urgent revascularization, and all-cause mortality. TIMI risk score was calculated for each patient, and each was also assigned a risk group based on electrocardiogram (ECG) changes and troponin levels only. After follow-up, Cox univariate and multivariate regression was used to evaluate the influence of potential risk factors on duration of event-free survival, and likelihood ratio tests to assess the fit of the models. RESULTS: Increasing TIMI risk score was associated with increased risk of events (p<0.001), as was higher risk group from ECG plus troponin stratification (p<0.001). The likelihood ratio comparison favoured the TIMI risk score (difference 13.910, 5 degrees of freedom, p = 0.016). DISCUSSION: The TIMI risk score is a valid tool for risk stratification in unselected cases with possible acute coronary syndrome. It is superior to ECG changes and troponin alone, although this simpler method also achieves good risk stratification.


Assuntos
Infarto do Miocárdio/diagnóstico , Troponina/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Revascularização Miocárdica/métodos , Valor Preditivo dos Testes , Estudos Prospectivos , Análise de Regressão , Medição de Risco/normas , Fatores de Risco , Síndrome
16.
J Pharmacol Toxicol Methods ; 54(2): 189-99, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16563806

RESUMO

INTRODUCTION: Regulatory and competitive pressure to reduce the QT interval prolongation risk of potential new drugs has led to focus on methods to test for inhibition of the human ether-a-go-go-related gene (hERG)-encoded K+ channel, the primary molecular target underlying this safety issue. Here we describe the validation of a method that combines medium-throughput with direct assessment of channel function. METHODS: The electrophysiological and pharmacological properties of hERG were compared using two methods: conventional, low-throughput electrophysiology and planar-array-based, medium-throughput electrophysiology (IonWorks HT). A pharmacological comparison was also made between IonWorks HT and an indirect assay (Rb+ efflux). RESULTS: Basic electrophysiological properties of hERG were similar whether recorded conventionally (HEK cells) or using IonWorks HT (CHO cells): for example, tail current V1/2 -12.1+/-5.0 mV (32) for conventional and -9.5+/-6.0 mV (46) for IonWorks HT (mean+/-S.D. (n)). A key finding was that as the number of cells per well was increased in IonWorks HT, the potency reported for a given compound decreased. Using the lowest possible cell concentration (250,000 cells/ml) and 89 compounds spanning a broad potency range, the pIC50 values from IonWorks HT (CHO-hERG) were found to correlate well with those obtained using conventional methodology (HEK-hERG)(r=0.90; p<0.001). Further validation using CHO-hERG cells with both methods confirmed the correlation (r=0.94; p<0.001). In contrast, a comparison of IonWorks HT and Rb+ efflux data with 649 compounds using CHO-hERG cells showed that the indirect assay consistently reported compounds as being, on average, 6-fold less potent, though the differences varied depending on chemical series. DISCUSSION: The main finding of this work is that providing a relatively low cell concentration is used in IonWorks HT, the potency information generated correlates well with that determined using conventional electrophysiology. The effect on potency of increasing cell concentration may relate to a reduced free concentration of test compound owing to partitioning into cell membranes. In summary, the IonWorks HT hERG assay can generate pIC50 values based on a direct assessment of channel function in a timeframe short enough to influence chemical design.


Assuntos
Eletrofisiologia/instrumentação , Canais de Potássio Éter-A-Go-Go/efeitos dos fármacos , Técnicas de Patch-Clamp/instrumentação , Bloqueadores dos Canais de Potássio/farmacologia , Animais , Células CHO , Linhagem Celular , Cricetinae , Canal de Potássio ERG1 , Humanos , Reprodutibilidade dos Testes , Rubídio/metabolismo
17.
Aquat Toxicol ; 77(3): 279-90, 2006 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-16483677

RESUMO

An extended early-life stage test (based on OECD test guideline 210) was developed to allow the evaluation of a weak environmental oestrogen, 4-tert-pentyphenol (4TPP), on sexual differentiation and gonadal development. Fathead minnow (Pimephales promelas) embryos were exposed to three concentrations of 4TPP (56, 180 and 560 microg l(-1)) in a flow-through system, at 25+/-1 degrees C, for <107 days post-hatch (dph). In addition, some embryos were exposed to 180 microg 4TPPl(-1) until 30 or 60 dph, after which they were exposed to dilution water only until 107 dph. At 30, 60 and 107 dph fish were evaluated for growth and gonadal development (via histology), and at 107 dph fish were also evaluated for secondary sexual characteristics (SSC), gonadosomatic index (GSI) and plasma vitellogenin (VTG). There were no effects of 4TPP on hatching success or survival, however, there was a delay in the time taken for embryos to hatch (560 microg 4TPPl(-1)). No treatment-related effects were observed on fish growth, with the exception of at 107 dph when the condition factor in female fish was reduced in all 4TPP continuous exposure treatments. Plasma VTG was only elevated in female fish exposed to 180 microg 4TPPl(-1) and inhibition of gonadal growth (GSI) occurred only in females exposed to 560 microg 4TPPl(-1). Histological examination of the gonads revealed delays and disruption in male sexual differentiation and development (180 microg 4TPPl(-1)) and no testicular tissue was observed in any fish exposed to 560 microg 4TPPl(-1). Mixed gonads (predominately testes with a scattering of primary oocytes) were present in fish exposed to all doses of 180 microg 4TPPl(-1) at 107 dph. Feminisation of the reproductive ducts (formation of an ovarian like cavity) occurred in the testis of all males exposed to 180 microg l(-1), regardless of length of 4TPP exposure. Results indicate that the period of 30-60 dph appears to be the sensitive window for disruption of formation of the reproductive duct and this effect is not reversible when the fish are transferred to dilution water. The data also show that this integrative test is suitable for the detection of a weak environmental oestrogen and comparisons of these results with that of a fish full life-cycle, in medaka, indicate that this test could be a suitable surrogate for a fish full life-cycle.


Assuntos
Cyprinidae/embriologia , Estrogênios/toxicidade , Fenóis/toxicidade , Testes de Toxicidade/métodos , Animais , Tamanho Corporal/efeitos dos fármacos , Cyprinidae/fisiologia , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/embriologia , Estrogênios/análise , Feminino , Feminização/induzido quimicamente , Feminização/veterinária , Gônadas/efeitos dos fármacos , Gônadas/embriologia , Rim/química , Rim/efeitos dos fármacos , Fígado/química , Fígado/efeitos dos fármacos , Masculino , Fenóis/análise , Distribuição Aleatória , Análise de Sobrevida , Fatores de Tempo , Testes de Toxicidade/veterinária , Vitelogeninas/sangue
18.
Neurosci Lett ; 633: 47-54, 2016 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-27637386

RESUMO

BACKGROUND: Deficits in facial emotion recognition have been associated with functional impairments in patients with Schizophrenia (SZ). Whilst a strong ecological argument has been made for the use of both dynamic facial expressions and varied emotion intensities in research, SZ emotion recognition studies to date have primarily used static stimuli of a singular, 100%, intensity of emotion. To address this issue, the present study aimed to investigate accuracy of emotion recognition amongst patients with SZ and healthy subjects using dynamic facial emotion stimuli of varying intensities. To this end an emotion recognition task (ERT) designed by Montagne (2007) was adapted and employed. METHODS: 47 patients with a DSM-IV diagnosis of SZ and 51 healthy participants were assessed for emotion recognition. Results of the ERT were tested for correlation with performance in areas of cognitive ability typically found to be impaired in psychosis, including IQ, memory, attention and social cognition. RESULTS: Patients were found to perform less well than healthy participants at recognising each of the 6 emotions analysed. Surprisingly, however, groups did not differ in terms of impact of emotion intensity on recognition accuracy; for both groups higher intensity levels predicted greater accuracy, but no significant interaction between diagnosis and emotional intensity was found for any of the 6 emotions. Accuracy of emotion recognition was, however, more strongly correlated with cognition in the patient cohort. DISCUSSION: Whilst this study demonstrates the feasibility of using ecologically valid dynamic stimuli in the study of emotion recognition accuracy, varying the intensity of the emotion displayed was not demonstrated to impact patients and healthy participants differentially, and thus may not be a necessary variable to include in emotion recognition research.


Assuntos
Emoções , Expressão Facial , Reconhecimento Psicológico , Psicologia do Esquizofrênico , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Cognição , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação , Adulto Jovem
19.
Schizophr Res ; 169(1-3): 135-140, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26421692

RESUMO

BACKGROUND: Cognitive deficits are a core feature of schizophrenia and related psychotic disorders and are associated with decreased levels of functioning. Behavioural interventions have shown success in remediating these deficits; determining how best to maximise this benefit while minimising the cost is an important next step in optimising this intervention for clinical use. AIMS: To examine the effects of a novel working-memory focused cognitive remediation (CR) training on cognitive difficulties based on internet delivery of training and weekly telephone support. METHOD: Participants with a diagnosis of psychosis (n=56) underwent either 8 weeks of CR (approximately 20 h) or 8 weeks of treatment as usual (TAU). General cognitive ability, working memory and episodic memory were measured both pre and post intervention for all participants. RESULTS: In addition to improvements on trained working memory tasks, CR training was associated with significant improvements in two tests of verbal episodic memory. No association between CR and changes in general cognitive ability was observed. Effect sizes for statistically significant changes in memory were comparable to those reported in the literature based primarily on 1:1 training. CONCLUSIONS: The cognitive benefits observed in this non-randomised preliminary study indicate that internet-based working memory training can be an effective cognitive remediation therapy. The successes and challenges of an internet-based treatment are discussed.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Computadores , Internet , Memória de Curto Prazo , Transtornos Psicóticos/terapia , Adulto , Antipsicóticos/uso terapêutico , Terapia Cognitivo-Comportamental/instrumentação , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Transtornos Psicóticos/psicologia , Telefone , Resultado do Tratamento
20.
Endocrinology ; 117(2): 607-12, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4017949

RESUMO

The transient inhibitory effect on thyroid secretion produced by high doses of iodide was investigated with respect to changes in the level of in vivo iodination of membrane tubulin. Iodinated tubulin, characterized by gel electrophoresis, immunoprecipitation, and peptide mapping, was shown to be associated with a thyroid membrane fraction, and totally absent from cytoplasmic proteins. The administration of an acute dose of 5 mg KI, although it inhibited thyroid secretion (as shown by an increase in TSH), did not have a significant effect on the level of iodination of membrane tubulin. Thus, the observed inhibition of thyroid secretion is probably unrelated to the level of iodination of tubulin. Although its function is not known at present, iodinated tubulin is probably involved in membrane-related phenomena.


Assuntos
Iodetos/farmacologia , Proteínas de Membrana/metabolismo , Glândula Tireoide/metabolismo , Tiroxina/metabolismo , Tri-Iodotironina/metabolismo , Tubulina (Proteína)/metabolismo , Animais , Feminino , Radioisótopos do Iodo , Ratos , Ratos Endogâmicos , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
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