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1.
Psychol Med ; 47(15): 2720-2730, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28866988

RESUMO

BACKGROUND: Cognitive remediation (CR) is a psychological therapy, which improves cognitive and social functioning in people with schizophrenia. It is now being implemented within routine clinical services and mechanisms of change are being explored. We designed a new generation computerised CR programme, CIRCuiTS (Computerised Interactive Remediation of Cognition - a Training for Schizophrenia), to enhance strategic and metacognitive processing, with an integrated focus on the transfer of cognitive skills to daily living. This large trial tested its feasibility to be delivered in therapist-led and independent sessions, and its efficacy for improved cognitive and social functioning. METHODS: A two arm single blind randomised superiority trial comparing CIRCuiTS plus treatment-as-usual (TAU) with TAU alone in 93 people with a diagnosis of schizophrenia. Cognitive, social functioning and symptom outcomes were assessed at pre- and post-therapy and 3 months later. RESULTS: 85% adhered to CIRCuiTS, completing a median of 28 sessions. There were significant improvements in visual memory at post-treatment (p = 0.009) and follow-up (p = 0.001), and a trend for improvements in executive function at post-treatment (p = 0.056) in favour of the CIRCuiTS group. Community function was also differentially and significantly improved in the CIRCuiTS group at post-treatment (p = 0.003) but not follow-up, and was specifically predicted by improved executive functions. CONCLUSIONS: CIRCuiTS was beneficial for improving memory and social functioning. Improved executive functioning emerges as a consistent predictor of functional gains and should be considered an important CR target to achieve functional change. A larger-scale effectiveness trial of CIRCuiTS is now indicated.

2.
BMC Psychiatry ; 16: 76, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-27000113

RESUMO

BACKGROUND: Suboptimal vitamin D levels have been identified in populations with psychotic disorders. We sought to explore the relationship between vitamin D deficiency, clinical characteristics and cardiovascular disease risk factors among people with established psychosis. METHODS: Vitamin D levels were measured in 324 community dwelling individuals in England with established psychotic disorders, along with measures of mental health, cardiovascular risk and lifestyle choices. Vitamin D deficiency was defined as serum 25-hydroxyvitamin D (25-OHD) levels below 10 ng/ml (equivalent to <25 nmol/L) and "sufficient" Vitamin D as above 30 ng/ml (>50 nmol/L). RESULTS: The mean 25-OHD serum level was 12.4 (SD 7.3) ng/ml, (range 4.0-51.7 ng/ml). Forty nine percent (n = 158) were vitamin D deficient, with only 14 % (n = 45) meeting criteria for sufficiency. Accounting for age, gender, ethnicity and season of sampling, serum 25-OHD levels were negatively correlated with waist circumference (r = -0.220, p < 0.002), triglycerides (r = -0.160, p = 0.024), total cholesterol (r = -0.144, p = 0.043), fasting glucose (r = -0.191, p = 0.007), HbA1c (r = -0.183, p = 0.01), and serum CRP levels (r = -0.211, p = 0.003) and were linked to the presence of metabolic syndrome. CONCLUSIONS: This is the largest cross sectional study of serum 25-OHD levels in community dwelling individuals with established psychosis, indicating a high level of vitamin D deficiency. Lower vitamin D levels are associated with increased cardiovascular disease risk factors and in particular metabolic syndrome. Further research is needed to define appropriate protocols for vitamin D testing and supplementation in practice to see if this can improve cardiovascular disease risk. TRIAL REGISTRATION: ISRCTN number is ISRCTN58667926 Date of registration: 23/04/2010.


Assuntos
Transtornos Psicóticos/sangue , Transtornos Psicóticos/epidemiologia , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia , Adulto , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Colesterol/sangue , Comorbidade , Estudos Transversais , Inglaterra , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Prevalência , Fatores de Risco , Triglicerídeos/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue
3.
Psychol Med ; 45(12): 2631, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26165543

RESUMO

The author regrets to announce that affiliation 8, in the above article (Gardner-Sood et al. 2015), contained an error in the author affiliation address and author surname, which were published in the approved article. The correct surname and affiliation address are given below. J. Eberhard, Clinical Psychiatric Research Center, Lund University, Skåne, Sweden

4.
Psychol Med ; 45(12): 2619-29, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25961431

RESUMO

BACKGROUND: The aims of the study were to determine the prevalence of cardiometabolic risk factors and establish the proportion of people with psychosis meeting criteria for the metabolic syndrome (MetS). The study also aimed to identify the key lifestyle behaviours associated with increased risk of the MetS and to investigate whether the MetS is associated with illness severity and degree of functional impairment. METHOD: Baseline data were collected as part of a large randomized controlled trial (IMPaCT RCT). The study took place within community mental health teams in five Mental Health NHS Trusts in urban and rural locations across England. A total of 450 randomly selected out-patients, aged 18-65 years, with an established psychotic illness were recruited. We ascertained the prevalence rates of cardiometabolic risk factors, illness severity and functional impairment and calculated rates of the MetS, using International Diabetes Federation (IDF) and National Cholesterol Education Program Third Adult Treatment Panel criteria. RESULTS: High rates of cardiometabolic risk factors were found. Nearly all women and most men had waist circumference exceeding the IDF threshold for central obesity. Half the sample was obese (body mass index ≥ 30 kg/m2) and a fifth met the criteria for type 2 diabetes mellitus. Females were more likely to be obese than males (61% v. 42%, p < 0.001). Of the 308 patients with complete laboratory measures, 57% (n = 175) met the IDF criteria for the MetS. CONCLUSIONS: In the UK, the prevalence of cardiometabolic risk factors in individuals with psychotic illnesses is much higher than that observed in national general population studies as well as in most international studies of patients with psychosis.


Assuntos
Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/psicologia , Transtornos Mentais/epidemiologia , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/psicologia , Adolescente , Adulto , Idoso , Benzodiazepinas/efeitos adversos , Benzodiazepinas/uso terapêutico , Doenças Cardiovasculares/etiologia , Centros Comunitários de Saúde Mental , Diabetes Mellitus Tipo 2/epidemiologia , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/tratamento farmacológico , Pessoa de Meia-Idade , Obesidade/epidemiologia , Prevalência , Fatores de Risco , População Rural , Distribuição por Sexo , Medicina Estatal , População Urbana , Adulto Jovem
5.
Psychol Med ; 42(5): 1013-23, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21910936

RESUMO

BACKGROUND: Psychological models of psychosis were examined using Experience Sampling Methods (ESM) to explore relationships between dimensions and appraisals of key symptoms and affect. METHOD: Individuals were signalled to complete ESM booklets 10 times per day for six consecutive days; 534 data points were obtained from 12 out-patients with psychosis. RESULTS: Although only 3.6% of spontaneous thoughts were psychosis related, these predicted more negative and less positive affect. Delusions and hallucinations, when present, were rated at a moderate level of intensity, and intensity was associated with distress, interference and preoccupation. Symptom dimensions were related to each other, with weaker associations with delusional conviction, which, it is hypothesized, may represent a separate factor. Conviction and appraisals relating to insight and decentring ('my problems are something to do with the way my mind works') were highly variable. Decentring appraisals of delusions, but not insight, were associated with less distress. Appraisals about the power of voices were strong predictors of negative affect and symptom distress. CONCLUSIONS: This study demonstrates that ESM is a useful methodology to capture 'online' variability in psychotic phenomenology and provides evidence supporting cognitive models, which posit that psychotic symptoms are multi-dimensional phenomena, shaped by appraisals that, in turn, predict their emotional and behavioural sequelae.


Assuntos
Atividades Cotidianas/psicologia , Afeto , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Autorrelato , Adulto , Delusões/diagnóstico , Delusões/psicologia , Feminino , Alucinações/diagnóstico , Alucinações/psicologia , Humanos , Masculino , Modelos Psicológicos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Índice de Gravidade de Doença
6.
Cogn Neuropsychiatry ; 17(3): 227-45, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21929281

RESUMO

INTRODUCTION: Research has suggested an association between personality factors and awareness in patients with dementia, yet valid measurement of premorbid personality is problematic. The present study aimed to better reveal the relationship between premorbid personality and awareness by using improved methodology. Moreover, the study aims to contrast the strength of the relationship of premorbid personality and awareness with that of cognitive factors. METHODS: Awareness of illness, symptoms, mnemonic and behavioural impairments, and treatment compliance were measured in 27 patients with mild-to-moderate Alzheimer's disease (AD) diagnosed by standard criteria for probable AD. Participant premorbid personality was measured using average retrospective Neuroticism-Extroversion-Openness Inventory (NEO-FFI) scores from two informants. Correlations were performed to investigate the relationship between awareness and personality dimensions, as well as measures of cognitive style, neuropsychological function, mood, carer burden, and sociodemographic factors. RESULTS: There was little relationship between awareness and personality scores, but modest associations between awareness and mood, age, and age of onset of first symptoms. Awareness of memory was related to memory functioning. Increased carer burden was associated with lack of awareness of cognitive-behavioural deficits but there were only few and weak associations between awareness and measures of cognitive functioning. CONCLUSIONS: There was little support for an association between previous personality and awareness in dementia. However, increased carer burden was associated specifically with lack of awareness of cognitive-behavioural deficits not deficits in ADL, whereas lower awareness of ADL and not cognitive-behavioural deficits was associated with age. Awareness of memory appeared to be a metamemory capacity. Mood and age rather than personality and cognition are stronger predictors of awareness in early Alzheimer's disease.


Assuntos
Doença de Alzheimer/psicologia , Conscientização/fisiologia , Cognição/fisiologia , Memória/fisiologia , Personalidade/fisiologia , Autoimagem , Afeto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Inventário de Personalidade , Índice de Gravidade de Doença
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 6086-6089, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019359

RESUMO

Premature infants or neonates in need of advanced clinical care must be transported to specialized hospitals. Past studies have examined vibrations experienced by patients during transport; however, multiple confounding factors limit the utility of on-road data. Hence, the development of a standardized test environment is warranted. The overall purpose of this project is to characterize vibrations during neonatal patient transport and develop mitigation strategies to reduce exposure. This paper focusses on the development of a laboratory test environment and procedure that enables studying the equipment vibration in a comprehensive and repeatable manner. For the first time, a complete neonatal patient transport system, including a stretcher, has been mounted on an industrial shaker. Results largely validate the system's ability to simulate on-road vibrations with high repeatability.


Assuntos
Hospitais Especializados , Vibração , Humanos , Lactente , Recém-Nascido
8.
J Dairy Sci ; 92(9): 4481-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19700709

RESUMO

Subacute ruminal acidosis reduces lactation performance in dairy cattle and most often occurs in animals fed a high concentrate:forage ration with large amounts of readily fermentable starch, which results in increased production of volatile fatty acids and lactic acid and a reduction in ruminal pH. Acarbose is commercially available (Glucobay, Bayer, Wuppertal, Germany) and indicated for the control of blood glucose in diabetic patients. In cattle, acarbose acts as an alpha-amylase and glucosidase inhibitor that slows the rate of degradation of starch to glucose, thereby reducing the rate of volatile fatty acid production and maintaining rumen pH at higher levels. The ability of acarbose to reverse the reduced feed intake and milk fat percentage and yield associated with a high concentrate:forage ration with a high risk of inducing subacute ruminal acidosis was evaluated in 2 experiments with lactating dairy cattle. In 2 preliminary experiments, the effects of a 70:30 concentrate:forage ration on ruminal pH and lactation were evaluated. Ruminal pH was monitored in 5 Holstein steers with ruminal cannulas every 10 min for 5 d. Ruminal pH was <5.5 for at least 4 h in 79% of the animal days. In dairy cows, the 70:30 concentrate:forage ration decreased feed intake 5%, milk fat percentage 7%, and milk fat yield 8% compared with a 50:50 concentrate:forage ration but did not affect milk yield. Early lactating dairy cattle were offered the 70:30 concentrate:forage ration with 0 or 0.75 g/d of acarbose added in a crossover design in 2 experiments. In the first experiment, acarbose increased dry matter feed intake (23.1 vs. 21.6 kg/d) and 3.5% fat-corrected milk yield (33.7 vs. 31.7 kg/d) because of an increase in percentage milk fat (3.33 vs. 3.04%) compared with control cows. In the second experiment, cows were fasted for 3 h before the morning feeding to induce consumption of a large meal to mimic conditions that might be associated with unplanned delayed feeding. In this experiment, acarbose also increased feed intake (22.5 vs. 21.8 kg/d) and 3.5% fat-corrected milk yield (36.9 vs. 33.9 kg/d) due to increased percentage milk fat (3.14 vs. 2.66%) compared with controls. Thus, acarbose reversed the decreased feed intake and low milk fat percentage and yield associated with feeding a high concentrate:forage ration shown to induce subacute ruminal acidosis in Holstein steers.


Assuntos
Acarbose/farmacologia , Acidose/veterinária , Dieta/veterinária , Lactação/efeitos dos fármacos , Leite , Rúmen/metabolismo , Gastropatias/veterinária , Animais , Peso Corporal/efeitos dos fármacos , Bovinos , Doenças dos Bovinos/metabolismo , Indústria de Laticínios , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Concentração de Íons de Hidrogênio , Hipoglicemiantes/farmacologia , Análise dos Mínimos Quadrados , Masculino , Leite/química , Leite/metabolismo , Rúmen/química
9.
J Dairy Sci ; 92(6): 2758-66, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19448010

RESUMO

A challenge model was used to evaluate a new approach to controlling acute acidosis. Acute acidosis reduces performance in both dairy and beef cattle and most often occurs as a consequence of ingestion of large amounts of readily fermentable starch, resulting in increased production of volatile fatty acids (VFA) and lactic acid and a reduction in ruminal pH. Acarbose is an alpha-amylase and glucosidase inhibitor that slows the rate of degradation of starch to glucose, thereby reducing the rate of VFA production and maintaining rumen pH at a more stable level. It is commercially available (Glucobay, Bayer, Wuppertal, Germany) and indicated for the control of blood glucose in diabetic patients. The ability of acarbose to reduce the incidence of acidosis and the comparative efficacies of acarbose, sodium bicarbonate, and monensin were tested in 3 acute acidosis challenge experiments in cattle. Rumen-cannulated Holstein steers were challenged with a mixture of 48.4% cornstarch, 48.4% ground corn, 2.1% sodium caseinate, and 1.1% urea with or without test substance. The challenge was administered at a rate of 12.5 g/kg of body weight (BW) as a slurry through the cannula directly into the rumen. Ruminal pH was monitored at 10-min intervals throughout the study. Animals were removed from study and rumen contents replaced if they exhibited acute acidosis as defined as pH <4.5. If acidosis was not observed within 24 h, animals were subjected to a second challenge. Ruminal fluid samples were taken for measurement of VFA and lactate concentrations at various intervals after the challenge. In experiment 1, the carbohydrate challenge induced acidosis in 4 of 4 control animals and 0 of 4 animals treated with 2.14 or 21.4 mg of acarbose/kg of BW in the challenge based on the criterion of pH <4.5. In experiment 2, the carbohydrate challenge induced acidosis in 4 of 7 control animals and 1 of 7 animals when 1.07 mg of acarbose/kg of BW was included in the challenge. In experiment 3, acidosis was induced in 7 of 7 animals in the control, 1% sodium bicarbonate, and 12 mg of monensin/kg of dry matter intake groups and in 3 of 8 steers administered 1.07 mg of acarbose/kg of BW in the challenge. Increases in lactate concentrations and decreases in total VFA associated with acute acidosis were mitigated by acarbose. Thus, acarbose, an amylase and glucosidase inhibitor, prevented or reduced the incidence of acidosis in an acute challenge model in steers and was more effective than monensin or sodium bicarbonate.


Assuntos
Acarbose/uso terapêutico , Acidose/veterinária , Doenças dos Bovinos/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Acarbose/farmacologia , Acidose/tratamento farmacológico , Doença Aguda , Animais , Bovinos , Carboidratos da Dieta/administração & dosagem , Ingestão de Alimentos/efeitos dos fármacos , Ácidos Graxos Voláteis/análise , Conteúdo Gastrointestinal/química , Concentração de Íons de Hidrogênio , Hipoglicemiantes/farmacologia , Ácido Láctico/análise , Masculino , Distribuição Aleatória , Fatores de Tempo
10.
Mol Biol Cell ; 11(5): 1919-32, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10793161

RESUMO

Maple syrup urine disease (MSUD) is an inborn error of metabolism caused by a deficiency in branched chain alpha-keto acid dehydrogenase that can result in neurodegenerative sequelae in human infants. In the present study, increased concentrations of MSUD metabolites, in particular alpha-keto isocaproic acid, specifically induced apoptosis in glial and neuronal cells in culture. Apoptosis was associated with a reduction in cell respiration but without impairment of respiratory chain function, without early changes in mitochondrial membrane potential and without cytochrome c release into the cytosol. Significantly, alpha-keto isocaproic acid also triggered neuronal apoptosis in vivo after intracerebral injection into the developing rat brain. These findings suggest that MSUD neurodegeneration may result, at least in part, from an accumulation of branched chain amino acids and their alpha-keto acid derivatives that trigger apoptosis through a cytochrome c-independent pathway.


Assuntos
Aminoácidos de Cadeia Ramificada/metabolismo , Grupo dos Citocromos c/metabolismo , Doença da Urina de Xarope de Bordo/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , Animais , Apoptose/efeitos dos fármacos , Caspase 3 , Caspases/metabolismo , Respiração Celular/efeitos dos fármacos , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/patologia , Fragmentação do DNA , Ativação Enzimática , Humanos , Membranas Intracelulares/metabolismo , Cetoácidos/metabolismo , Cetoácidos/farmacologia , Leucina/metabolismo , Leucina/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Camundongos , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neurônios/patologia , Ratos , Ratos Wistar
11.
Drugs Today (Barc) ; 53(9): 469-476, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29238760

RESUMO

Dinutuximab is a monoclonal antibody targeted at disialoganglioside (GD2), a tumor-associated antigen widely expressed in human neuroblastoma cells. The incorporation of dinutuximab into standard treatment regimens for patients with high-risk neuroblastoma has changed the landscape of neuroblastoma therapy. Dinutuximab has shown to be effective in prolonging survival for patients receiving standard multimodal treatment regimens and has now become standard of care during the final phase of treatment. More recently, it has also shown promising efficacy and tolerability in patients with relapsed or progressive neuroblastoma. The most effective way of incorporating dinutuximab into treatment protocols is still being explored, and is the focus of numerous ongoing clinical trials.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Antineoplásicos/administração & dosagem , Neuroblastoma/tratamento farmacológico , Animais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacologia , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Criança , Humanos , Recidiva Local de Neoplasia , Taxa de Sobrevida
12.
Eur Psychiatry ; 42: 1-7, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28199868

RESUMO

BACKGROUND: In recent years the association between sexual dysfunction (SD) and obesity in the general population has drawn major attention. Although sexual dysfunction is common in psychosis, its relationship with weight gain and obesity remains unclear. AIMS: To investigate the association between sexual dysfunction and obesity in a cohort of patients with first episode psychosis. METHOD: Sexual function was assessed in a cohort of patients with first episode psychosis using the Sexual Function Questionnaire (SFQ). Anthropometric measures, including weight, BMI, waist, waist-hip ratio were investigated. Additionally, leptin and testosterone were investigated in male patients. RESULTS: A total of 116 patients (61 males and 55 females) were included. Of these 59% of males and 67.3% of females showed sexual dysfunction (SD) according to the SFQ. In males, higher SFQ scores were significantly correlated with higher BMI (Std. ß=0.36, P=0.01), higher leptin levels (Std. ß=0.34, P=0.02), higher waist-hip ratio (Std. ß=0.32, P=0.04) and lower testosterone levels (Std. ß=-0.44, P=0.002). In contrast, in females, SFQ scores were not associated with any of these factors. CONCLUSIONS: While sexual dysfunction is present in both female and male patients with their first episode of psychosis, only in males is sexual dysfunction associated with increased BMI and waist-hip ratio. The association between SD, BMI, low levels of testosterone and high levels of leptin suggest that policies that lead to healthier diets and more active lifestyles can be beneficial at least, to male patients.


Assuntos
Obesidade Abdominal/complicações , Transtornos Psicóticos/complicações , Disfunções Sexuais Psicogênicas/etiologia , Adulto , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Aumento de Peso
13.
Eur Psychiatry ; 34: 1-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26928340

RESUMO

BACKGROUND: Therapeutic relationships are a central component of community treatment for psychosis and thought to influence clinical and social outcomes, yet there is limited research regarding the potential influence of professional characteristics on positive therapeutic relationships in community care. It was hypothesised that professionals' relating style and attitudes toward their work might be important, and thus this exploratory study modelled associations between these characteristics and therapeutic relationships developed in community psychosis treatment. METHODS: Dyads of professionals and young patients with psychosis rated their therapeutic relationships with each other. Professionals also completed measures of attachment style, therapeutic optimism, outcome expectancy, and job attitudes regarding working with psychosis. RESULTS: Professionals' anxious attachment predicted less positive professional therapeutic relationship ratings. In exploratory directed path analysis, data also supported indirect effects, whereby anxious professional attachment predicts less positive therapeutic relationships through reduced professional therapeutic optimism and less positive job attitudes. CONCLUSIONS: Professional anxious attachment style is directly associated with the therapeutic relationship in psychosis, and indirectly associated through therapeutic optimism and job attitudes. Thus, intervening in professional characteristics could offer an opportunity to limit the impact of insecure attachment on therapeutic relationships in psychosis.


Assuntos
Atitude do Pessoal de Saúde , Apego ao Objeto , Relações Profissional-Paciente , Transtornos Psicóticos/terapia , Adulto , Serviços Comunitários de Saúde Mental , Feminino , Humanos , Masculino , Satisfação do Paciente , Transtornos Psicóticos/psicologia , Adulto Jovem
14.
Biochim Biophys Acta ; 454(2): 285-97, 1976 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-136989

RESUMO

Four gene products involved in the enzymatic synthesis of enterochelin from 2,3-dihydroxybenzoate, L-serine and ATP (Luke, R.K.L. and Gibson, F. (1971) J. Bacteriol. 107,557-562; Woodrow, G.C., Young, I.G. and Gibson, F. (1975) J. Bacteriol. 124, 1-6) have been partially purified using a previously reported fractionation procedure (Bryce, G.F. and Brot, N. (1972) Biochemistry 11, 1708-1715). The products of genes E, F and G have been separated from each other and correspond to the E1, E2 and E3 activities described by Bryce and Brot. These three gene products were not completely separated from the product of gene D. We refer to these gene products as components E, F, G and D of the enzymic apparatus for biosynthesis of enterochelin. Certain properties and functions of the four semi-purified components have been investigated. The E component is involved in the activation of 2,3-dihydroxybenzoate and the F component in the activation of L-serine. The D component physically associates with the F and G components during gel filtration and chromatography on DEAE Sephadex. It is proposed that the synthesis of enterochelin from L-serine and 2,3-dihydroxybenzoic acid is catalysed in vivo by a multienzyme complex, enterochelin synthetase.


Assuntos
Enterobactina/metabolismo , Escherichia coli/metabolismo , Hidroxibenzoatos/metabolismo , Serina/análogos & derivados , Trifosfato de Adenosina/metabolismo , Sistema Livre de Células , Escherichia coli/efeitos dos fármacos , Etilmaleimida/farmacologia , Biossíntese Peptídica , Serina/metabolismo
15.
Biochim Biophys Acta ; 525(1): 209-18, 1978 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-150859

RESUMO

Properties of the enzyme which hydrolyses enterochelin (a cyclic trimer of 2,3-dihydroxy-N-benzoyl-L-serine) to 2,3-dihydroxybenzoylserine have been investigated with a view to resolving discrepancies between earlier reports. Enterochelin esterase, previously reported to consists of two components (O'Brien, I.G., Cox, G.B. and Gibson, F. (1971) Biochim. Biophys. Acta 237, 537-549), has been shown to be fully active in the absence of the so-called A component. The hydrolase described previously (Bryce, G.F. and Brot, N. (1972) Biochemistry 11, 1708-1715) as being able to break down enterochelin but not its iron complex, ferric-enterochelin, appears to be identical with the B component of enterochelin esterase. The single component enterochelin esterase corresponding to what was previously described as component B, hydrolyses both enterochelin and ferric-enterochelin. Under the assay conditions used, enterochelin is hydrolysed 2.5 times faster than the complex. Enzymatic activity is inhibited by N-ethylmaleimide and is lost rapidly at 37 degrees C. Activity is stabilized in the presence of ferric-enterochelin, enterochelin, dithiothreitol or certain protein fractions.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Enterobactina/metabolismo , Escherichia coli/metabolismo , Ferro/metabolismo , Serina/análogos & derivados , Ditiotreitol/farmacologia , Etilmaleimida/farmacologia , Hidrólise , Serina/metabolismo , Soroalbumina Bovina/farmacologia , Especificidade por Substrato
16.
Biochim Biophys Acta ; 660(2): 371-4, 1981 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-6456771

RESUMO

Enterochelin synthetase activity is controlled by both repression and feed-back inhibition mechanisms. Inclusion of iron in growth media results in synthesis of all four (D, E, F and G) components of enterochelin synthetase being repressed. The specific inhibition of L-serine activation (partial reaction catalyzed by the F component) by the end products, ferric-enterochelin and 2,3-dihydroxybenzoylserine, is shown to inhibit overall enterochelin synthetase activity.


Assuntos
Escherichia coli/enzimologia , Peptídeo Sintases/metabolismo , 2,2'-Dipiridil/farmacologia , Cloretos , Enterobactina/farmacologia , Retroalimentação , Compostos Férricos/farmacologia , Peptídeo Sintases/antagonistas & inibidores , Serina/análogos & derivados , Serina/metabolismo , Serina/farmacologia
17.
Biochim Biophys Acta ; 614(1): 185-95, 1980 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-6446939

RESUMO

Further evidence is presented in support of the proposal made previously (Greenwood, K.T. and Luke, R.K.J. (1976) Biochim. Biophys. Acta 454, 285-297) that components of the Escherichia coli enterochelin synthetase system physicaloly associate to form enzyme complexes. Evidence for the existence of three enzyme complexes, designated in order of increasing stability G-D < F-D < F-D-G, has been obtained following gel filtration and chromatography on DEAE-Sephadex. Persistence of the F-D and G-D complexes during chromatography appears to depend on the flow rate of the column. On the basis of complementation with appropriate ent mutants of E. coli, activities corresponding to those of the D, E, F and G components of enterochelin synthetase in E. coli have been detected in cell-extracts of both Salmonella typhimurium and Klebsiella pneumoniae (formerly Aerobacter aerogenes) strains. These are designated D', E', F' and G' activities. Components E' and G' are eluted from Sephadex G-100 in similar fashion to their E. coli counterparts. Peaks of F' and D' activities however, are eluted together at a position corresponding to that of the E. coli F component. We suggest that in S. typhimurium and K. pneumoniae, either a single polypeptide combines the functions of the E. coli F and D components, or that separate F' and D' components form a stable complex and that activity of uncomplexed D' and component was not detected under the conditions used during chromatography and assay.


Assuntos
Enterobactina/metabolismo , Escherichia coli/enzimologia , Klebsiella pneumoniae/enzimologia , Peptídeo Sintases/análise , Salmonella typhimurium/enzimologia , Serina/análogos & derivados , Cromatografia DEAE-Celulose
18.
Eur Psychiatry ; 30(1): 152-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25541346

RESUMO

BACKGROUND: Why patients with psychosis use cannabis remains debated. The self-medication hypothesis has received some support but other evidence points towards an alleviation of dysphoria model. This study investigated the reasons for cannabis use in first-episode psychosis (FEP) and whether strength in their endorsement changed over time. METHODS: FEP inpatients and outpatients at the South London and Maudsley, Oxleas and Sussex NHS Trusts UK, who used cannabis, rated their motives at baseline (n=69), 3 months (n=29) and 12 months (n=36). A random intercept model was used to test the change in strength of endorsement over the 12 months. Paired-sample t-tests assessed the differences in mean scores between the five subscales on the Reasons for Use Scale (enhancement, social motive, coping with unpleasant affect, conformity and acceptance and relief of positive symptoms and side effects), at each time-point. RESULTS: Time had a significant effect on scores when controlling for reason; average scores on each subscale were higher at baseline than at 3 months and 12 months. At each time-point, patients endorsed 'enhancement' followed by 'coping with unpleasant affect' and 'social motive' more highly for their cannabis use than any other reason. 'Conformity and acceptance' followed closely. 'Relief of positive symptoms and side effects' was the least endorsed motive. CONCLUSIONS: Patients endorsed their reasons for use at 3 months and 12 months less strongly than at baseline. Little support for the self-medication or alleviation of dysphoria models was found. Rather, patients rated 'enhancement' most highly for their cannabis use.


Assuntos
Abuso de Maconha/psicologia , Fumar Maconha/psicologia , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Adaptação Psicológica , Adulto , Idoso , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Comportamento Social
19.
Brain Pathol ; 10(1): 17-29, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10668892

RESUMO

Fas/CD95/Apo-1 is a cell surface receptor that transduces apoptotic death signals following activation and has been implicated in triggering apoptosis in infected or damaged cells in disease states. Apoptosis is a major mechanism of neuronal loss following hypoxic-ischemic injury to the developing brain, although the role of Fas in this process has not been studied in detail. In the present study, we have investigated the expression and function of Fas in neuronal cells in vitro and in vivo. Fas was found to be expressed in the 14 day old rat brain, with strongest expression in the cortex, hippocampus and cerebellum. Cross-linking of Fas induced neuronal apoptosis both in neuronal PC12 cells in culture and following intracerebral injection in vivo, indicating that neuronal Fas was functional as a death receptor. This death was shown to be caspase dependent in primary neuronal cultures and was blocked by the selective caspase 8 inhibitor IETD. Finally, cerebral hypoxia-ischemia resulted in a strong lateralised upregulation of Fas in the hippocampus, that peaked six to twelve hours after the insult and was greater on the side of injury. These results suggest that Fas may be involved in neuronal apoptosis following hypoxic-ischemic injury to the developing brain.


Assuntos
Apoptose/imunologia , Encéfalo/fisiopatologia , Hipóxia-Isquemia Encefálica/fisiopatologia , Neurônios/imunologia , Neurônios/patologia , Regulação para Cima/imunologia , Receptor fas/imunologia , Receptor fas/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/imunologia , Encéfalo/patologia , Caspases/imunologia , Córtex Cerebral/imunologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Hipocampo/imunologia , Hipocampo/patologia , Hipocampo/fisiopatologia , Hipóxia-Isquemia Encefálica/imunologia , Imunoglobulina M/imunologia , Imunoglobulina M/farmacologia , Células PC12 , Ratos , Ratos Wistar
20.
Am J Psychiatry ; 158(2): 234-43, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11156806

RESUMO

OBJECTIVE: Imaging studies of schizophrenia have repeatedly demonstrated global abnormalities of cerebral and ventricular volumes. However, pathological changes at more local levels of brain organization have not yet been so clearly characterized because of the few brain regions of interest heretofore included in morphometric analyses as well as heterogeneity of patient samples. METHOD: Dual echo magnetic resonance imaging (MRI) data were acquired at 1.5 T from 27 right-handed patients who met DSM-IV criteria for schizophrenia with enduring negative symptoms and from 27 healthy comparison subjects. Between-group differences in gray and white matter volume were estimated at each intracerebral voxel after registration of the images in standard space. The relationship between clinical symptom scores and brain structure was also examined within the patient group. Spatial statistics and permutation tests were used for inference. RESULTS: Significant deficits of gray matter volume in the patient group were found at three main locations: 1) the left superior temporal gyrus and insular cortex, 2) the left medial temporal lobe (including the parahippocampal gyrus and hippocampus), and 3) the anterior cingulate and medial frontal gyri. The volume of these three regions combined was 14% lower in the patients relative to the comparison subjects. White matter deficits were found in similar locations in the left temporal lobe and extended into the left frontal lobe. The patient group showed a relative excess of gray matter volume in the basal ganglia. Within the patient group, basal ganglia gray matter volume was positively correlated with positive symptom scores. CONCLUSIONS: Anatomical abnormalities in these schizophrenic patients with marked negative symptoms were most evident in left hemispheric neocortical and limbic regions and related white matter tracts. These data are compatible with models that depict schizophrenia as a supraregional disorder of multiple, distributed brain regions and the axonal connections between them.


Assuntos
Lobo Frontal/anatomia & histologia , Sistema Límbico/anatomia & histologia , Vias Neurais/anatomia & histologia , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Lobo Temporal/anatomia & histologia , Adulto , Gânglios da Base/anatomia & histologia , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Masculino
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