Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
2.
Neuroscience ; 479: 70-90, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34648866

RESUMO

Deficiency in peroxisome proliferator-activated receptor gamma coactivator 1-alpha. (PGC-1α) expression or function is implicated in numerous neurological and psychiatric disorders. PGC-1α is required for the expression of genes involved in synchronous neurotransmitter release, axonal integrity, and metabolism, especially in parvalbumin-positive interneurons. As a transcriptional coactivator, PGC-1α requires transcription factors to specify cell-type-specific gene programs; while much is known about these factors in peripheral tissues, it is unclear if PGC-1α utilizes these same factors in neurons. Here, we identified putative transcription factors controlling PGC-1α-dependent gene expression in the brain using bioinformatics and then validated the role of the top candidate in a knockout mouse model. We transcriptionally profiled cells overexpressing PGC-1α and searched for over-represented binding motifs in the promoters of upregulated genes. Binding sites of the estrogen-related receptor (ERR) family of transcription factors were enriched, and blockade of ERRα attenuated PGC-1α-mediated induction of mitochondrial and synaptic genes in cell culture. Localization in the mouse brain revealed enrichment of ERRα expression in parvalbumin-expressing neurons with tight correlation of expression with PGC-1α across brain regions. In ERRα null mice, PGC-1α-dependent genes were reduced in multiple regions, including neocortex, hippocampus, and cerebellum, though not to the extent observed in PGC-1α null mice. Behavioral assessment revealed ambulatory hyperactivity in response to amphetamine and impairments in sensorimotor gating without the overt motor impairment characteristic of PGC-1α null mice. These data suggest that ERRα is required for normal levels of expression of PGC-1α-dependent genes in neurons but that additional factors may be involved in their regulation.


Assuntos
Encéfalo , Receptores de Estrogênio , Animais , Encéfalo/metabolismo , Expressão Gênica , Regulação da Expressão Gênica , Camundongos , Camundongos Knockout , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Fatores de Transcrição , Receptor ERRalfa Relacionado ao Estrogênio
3.
Nat Commun ; 10(1): 83, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30622257

RESUMO

Mitochondrial topoisomerase IB (TOP1MT) is a nuclear-encoded topoisomerase, exclusively localized to mitochondria, which resolves topological stress generated during mtDNA replication and transcription. Here, we report that TOP1MT is overexpressed in cancer tissues and demonstrate that TOP1MT deficiency attenuates tumor growth in human and mouse models of colon and liver cancer. Due to their mitochondrial dysfunction, TOP1MT-KO cells become addicted to glycolysis, which limits synthetic building blocks and energy supply required for the proliferation of cancer cells in a nutrient-deprived tumor microenvironment. Mechanistically, we show that TOP1MT associates with mitoribosomal subunits, ensuring optimal mitochondrial translation and assembly of oxidative phosphorylation complexes that are critical for sustaining tumor growth. The TOP1MT genomic signature profile, based on Top1mt-KO liver cancers, is correlated with enhanced survival of hepatocellular carcinoma patients. Our results highlight the importance of TOP1MT for tumor development, providing a potential rationale to develop TOP1MT-targeted drugs as anticancer therapies.


Assuntos
Carcinogênese/patologia , Carcinoma Hepatocelular/patologia , DNA Topoisomerases Tipo I/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Hepáticas/patologia , Mitocôndrias/metabolismo , Biossíntese de Proteínas , Animais , Carcinógenos/toxicidade , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Núcleo Celular/metabolismo , Proliferação de Células , DNA Topoisomerases Tipo I/genética , DNA Mitocondrial/genética , DNA Mitocondrial/isolamento & purificação , Conjuntos de Dados como Assunto , Metabolismo Energético , Feminino , Fibroblastos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glicólise , Células HCT116 , Humanos , Fígado/citologia , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Camundongos , Camundongos Knockout , Camundongos Nus , Mitocôndrias/patologia , Prognóstico , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Affect Disord ; 225: 129-136, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28826089

RESUMO

BACKGROUND: Sex differences in emotion processing may play a role in women's increased risk for Major Depressive Disorder (MDD). However, studies of sex differences in brain mechanisms involved in emotion processing in MDD (or interactions of sex and diagnosis) are sparse. METHODS: We conducted an event-related fMRI study examining the interactive and distinct effects of sex and MDD on neural activity during a facial emotion perception task. To minimize effects of current affective state and cumulative disease burden, we studied participants with remitted MDD (rMDD) who were early in the course of the illness. In total, 88 individuals aged 18-23 participated, including 48 with rMDD (32 female) and 40 healthy controls (HC; 25 female). RESULTS: fMRI revealed an interaction between sex and diagnosis for sad and neutral facial expressions in the superior frontal gyrus and left middle temporal gyrus. Results also revealed an interaction of sex with diagnosis in the amygdala. LIMITATIONS: Data was from two sites, which might increase variability, but it also increases power to examine sex by diagnosis interactions. CONCLUSIONS: This study demonstrates the importance of taking sex differences into account when examining potential trait (or scar) mechanisms that could be useful in identifying individuals at-risk for MDD as well as for evaluating potential therapeutic innovations.


Assuntos
Tonsila do Cerebelo/patologia , Depressão/patologia , Expressão Facial , Córtex Pré-Frontal/patologia , Depressão/psicologia , Emoções , Face , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Caracteres Sexuais , Adulto Jovem
5.
BMC Public Health ; 17(1): 211, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28212638

RESUMO

BACKGROUND: The wide-ranging program of reforms brought about by the Health and Social Care Act (2012) in England fundamentally changed the operation of the public health system, moving responsibility for the commissioning and delivery of services from the National Health Service to locally elected councils and a new national public health agency. This paper explores the ways in which the reforms have altered public health commissioning. METHODS: We conducted multi-methods research over 33 months, incorporating national surveys of Directors of Public Health and local council elected members at two time-points, and in-depth case studies in five purposively selected geographical areas. RESULTS: Public health commissioning responsibilities have changed and become more fragmented, being split amongst a range of different organisations, most of which were newly created in 2013. There is much change in the way public health commissioning is done, in who is doing it, and in what is commissioned, since the reforms. There is wider consultation on decisions in the local council setting than in the NHS, and elected members now have a strong influence on public health prioritisation. There is more (and different) scrutiny being applied to public health contracts, and most councils have embarked on wide-ranging changes to the health improvement services they commission. Public health money is being used in different ways as councils are adapting to increasing financial constraint. CONCLUSIONS: Our findings suggest that, while some of the intended opportunities to improve population health and create a more joined-up system with clearer leadership have been achieved, fragmentation, dispersed decision-making and uncertainties regarding funding remain significant challenges. There have been profound changes in commissioning processes, with consequences for what health improvement services are ultimately commissioned. Time (and further research) will tell if any of these changes lead to improved population health outcomes and reduced health inequalities, but many of the opportunities brought about by the reforms are threatened by the continued flux in the system.


Assuntos
Reforma dos Serviços de Saúde/organização & administração , Administração de Serviços de Saúde , Medicina Estatal/organização & administração , Contratos , Inglaterra , Humanos , Liderança
6.
Psychol Med ; 46(5): 1055-67, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26784396

RESUMO

BACKGROUND: Recent meta-analyses of resting-state networks in major depressive disorder (MDD) implicate network disruptions underlying cognitive and affective features of illness. Heterogeneity of findings to date may stem from the relative lack of data parsing clinical features of MDD such as phase of illness and the burden of multiple episodes. METHOD: Resting-state functional magnetic resonance imaging data were collected from 17 active MDD and 34 remitted MDD patients, and 26 healthy controls (HCs) across two sites. Participants were medication-free and further subdivided into those with single v. multiple episodes to examine disease burden. Seed-based connectivity using the posterior cingulate cortex (PCC) seed to probe the default mode network as well as the amygdala and subgenual anterior cingulate cortex (sgACC) seeds to probe the salience network (SN) were conducted. RESULTS: Young adults with remitted MDD demonstrated hyperconnectivity of the left PCC to the left inferior frontal gyrus and of the left sgACC to the right ventromedial prefrontal cortex (PFC) and left hippocampus compared with HCs. Episode-independent effects were observed between the left PCC and the right dorsolateral PFC, as well as between the left amygdala and right insula and caudate, whereas the burden of multiple episodes was associated with hypoconnectivity of the left PCC to multiple cognitive control regions as well as hypoconnectivity of the amygdala to large portions of the SN. CONCLUSIONS: This is the first study of a homogeneous sample of unmedicated young adults with a history of adolescent-onset MDD illustrating brain-based episodic features of illness.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/fisiopatologia , Vias Neurais/fisiopatologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Função Executiva , Feminino , Lobo Frontal/fisiopatologia , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Recidiva , Adulto Jovem
7.
J Public Health (Oxf) ; 38(3): e201-e208, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26487701

RESUMO

BACKGROUND: Following the Health and Social Care Act in England, public health teams were formally transferred from the NHS to local authorities in April 2013. METHODS: Online survey of Directors of Public Health (DsPH) in local authorities in England (n = 152) to investigate their experience within local government 1 year on. Tests of association were used to explore relationships between the perceived integration and influence of public health, and changes in how the public health budget was being spent. RESULTS: The organization of and managerial arrangements for public health within councils varied. Most DsPH felt that good relationships had been established within the council, and the move had made them more able to influence priorities for health improvement, even though most felt their influence was limited. Changes in commissioning using the public health budget were already widespread and included the de-commissioning of services. CONCLUSIONS: There was a widespread feeling amongst DsPH that they had greater influence since the reforms, and that this went across the local authority and beyond. Public health's influence was most apparent when the transfer of staff to local government had gone well, when collaborative working relationships had developed, and when local partnership groups were seen as being effective.


Assuntos
Administração em Saúde Pública , Orçamentos/organização & administração , Humanos , Governo Local , Inovação Organizacional , Administração em Saúde Pública/economia , Administração em Saúde Pública/legislação & jurisprudência , Administração em Saúde Pública/métodos , Administração em Saúde Pública/estatística & dados numéricos , Medicina Estatal/legislação & jurisprudência , Medicina Estatal/organização & administração , Medicina Estatal/estatística & dados numéricos , Inquéritos e Questionários , Reino Unido
8.
Psychol Health ; 26(6): 751-64, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21432726

RESUMO

Headache is the most common neurological symptom presenting to general practitioners (GPs). Identifying factors predicting outcome in patients consulting their GPs for headache may help GPs with prognosis and choose management strategies which would improve patient care. We followed up a cohort of patients receiving standard medical care, recruited from 18 general practices in the South Thames region of England, approximately 9 months after their initial participation in the study. Of the baseline sample (N=255), 134 provided both full baseline and follow-up data on measures of interest. We determined associations between patients' follow-up scores on the Headache Impact Test-6 and baseline characteristics (including headache impact and frequency scores, mood, attributions about psychological/medical causes of their headaches, satisfaction with GP care and illness perceptions). Greater impact and stronger beliefs about the negative consequences of headaches at baseline were the strongest predictors of poor outcome at follow-up.


Assuntos
Transtornos da Cefaleia Primários/terapia , Cefaleia/terapia , Comportamento de Doença , Satisfação do Paciente , Adolescente , Adulto , Idoso , Inglaterra , Feminino , Medicina Geral , Cefaleia/psicologia , Transtornos da Cefaleia Primários/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Resultado do Tratamento
9.
Int J Epidemiol ; 30(4): 756-65, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11511599

RESUMO

BACKGROUND: Our previous study found that alcohol abstainers use acute services more and preventative services less than safe level drinkers. The observed relationships between four categories of alcohol consumption and service use were J-shaped for acute services and inverted J-shaped for preventive services. The aim of this paper was to further investigate these relationships. METHODS: The design was a health and lifestyle survey of 41 000 randomly-sampled adults in SE England. The response rate was 60%. Distinctive subgroups within the alcohol abstainer group were investigated using cluster analysis, based on socio-demographic and health status variables. Odds ratios for services use for the abstainer clusters, and three alcohol consumption groups were estimated from a logistic regression model which included age, social class, ethnic group, employment status, household composition, whether the respondent was a carer, smoking habit, use of private health insurance, and health status. RESULTS: Two clusters were formed for both males and females. Cluster 1 comprised, on average, older, frailer, and more disabled people. Cluster 2 comprised younger, healthier people, a greater proportion of whom belonged to ethnic minority groups. Cluster 2 had similar rates of use of Accident & Emergency, GP, optician, and dental services compared with safe level drinkers. Cluster 1's rates differed from those of both Cluster 2 and safe level drinkers in almost all instances. CONCLUSIONS: The J- and inverted J-shaped relationships between alcohol consumption and service use are partly explained by a subgroup of abstainers who are older, of less good health, and who use hospital, clinic, and domiciliary healthcare services much more than safe level drinkers.


Assuntos
Consumo de Bebidas Alcoólicas , Temperança , Adulto , Idoso , Distribuição de Qui-Quadrado , Análise por Conglomerados , Demografia , Inglaterra , Feminino , Serviços de Saúde/estatística & dados numéricos , Indicadores Básicos de Saúde , Inquéritos Epidemiológicos , Humanos , Estilo de Vida , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos
10.
Addiction ; 94(10): 1523-32, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10790904

RESUMO

AIMS: To investigate the hypothesis that increasing alcohol consumption is accompanied by increasing use of acute, but decreasing use of preventative, medical services among the general population. DESIGN AND PARTICIPANTS: Health and life-style survey of 41,000 randomly-sampled adults in SE England who self-completed a validated questionnaire covering socio-demographics, alcohol and tobacco usage and use of acute (A&E department and general practitioner) and preventative (dental, optician, mammography and cervical cytology) services: the response rate was 60%. MEASUREMENTS: Comparative use of acute and preventative health care services by patients with varying consumption of alcoholic beverages. This was estimated by the odds ratio for service use, after correcting for the following confounding variables; age, social class, ethnic group, employment status, whether lives with children or with other adults, whether is a career, limiting long-term illness, depression status, smoking habit and use of private health insurance. FINDINGS: There was increased use of accident and emergency services by the harmful and intermediate drinking groups compared with the safe drinking group. Male abstainers attended their A&E departments more frequently than 'safe limit' drinkers. With respect to preventative services, both male and female abstainers and harmful drinkers used dental services less than safe limit drinkers. For females, mammography and cervical cytology services were less frequently used by abstainers and by harmful drinkers. CONCLUSIONS: This study supports the generally held view that heavy alcohol consumers are disproportionate users of acute medical services but they are relative under-users of preventative medical care services. Alcohol abstainers are also over-users of acute services, but under-users of preventative services. These latter observations are relevant to the claims that moderate alcohol consumers have lower apparent morbidity and mortality rates compared to abstainers.


Assuntos
Consumo de Bebidas Alcoólicas , Alcoolismo/epidemiologia , Clínicas de Dor/estatística & dados numéricos , Serviços Preventivos de Saúde/estatística & dados numéricos , Distribuição por Idade , Consumo de Bebidas Alcoólicas/prevenção & controle , Feminino , Nível de Saúde , Humanos , Estilo de Vida , Masculino , Distribuição por Sexo , Inquéritos e Questionários
11.
J Cell Sci ; 111 ( Pt 1): 99-109, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9394016

RESUMO

A chemotaxis chamber has been developed to analyze both the velocity and the directionality of individual T cells in gradients of high molecular mass molecules over long periods of time. Employing this chamber, it is demonstrated that syncytia induced by HIV in SUP-T1 cell cultures release two T cell chemoattractants with approximate molecular masses of 30 and 120 kDa. Neither uninfected single cells nor polyethylene glycol-induced syncytia release detectable chemoattractant, suggesting that these chemoattractants are linked to HIV infection. Soluble gp120 functions as a T cell chemoattractant and the addition of anti-gp120 antibody to syncytium-conditioned medium blocks the high molecular mass chemoattractant activity but not the low molecular mass activity. The addition of anti-CD4 antibody to syncytium-conditioned medium also blocks the high molecular mass chemoattractant activity but not the low molecular mass activity. These results demonstrate that HIV-induced T cell syncytia release a low and a high molecular mass T cell chemoattractant, and suggest that the high molecular mass factor is gp120 and that it functions through the CD4 receptor.


Assuntos
Células Gigantes/virologia , HIV-1/imunologia , Linfócitos T/citologia , Linfócitos T/virologia , Antígenos CD4/imunologia , Técnicas de Cultura de Células/métodos , Linhagem Celular Transformada , Fatores Quimiotáticos/metabolismo , Quimiotaxia/imunologia , Células Gigantes/metabolismo , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/metabolismo , Humanos , Microscopia/instrumentação , Microscopia/métodos , Peso Molecular
12.
Dev Biol ; 169(2): 644-61, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7781905

RESUMO

Much of the cell surface on the ciliate Tetrahymena thermophila is covered by a polarized lattice of cytoskeletal structures that are associated with basal bodies of the ciliary rows. Unique structural landmarks, including an oral apparatus and contractile vacuole pores, develop before cell division in localized domains located, respectively, posterior and anterior to the transverse fission zone. All of these structures can be visualized by specific monoclonal antibodies. A single-locus recessive mutation, disorganized-A (disA), primarily affects the striated rootlets of the ciliary-row basal bodies and brings about a severe disorganization in the positioning and orientation of these basal bodies and associated cytoskeletal elements. Nonetheless, the new oral apparatus, contractile vacuole pores, and other unique structures appeared at or near their normal sites along the anteroposterior axis of disA cells, indicating that the positioning of these localized structures is not dependent on the integrity of the ciliary rows. Abnormalities were present in the details of construction of some of the localized structures and in aspects of cell shape that may be influenced by these details. In the main, however, analysis of disA mutant cells indicates that intracellular domains near the cell poles develop independently of the vectorial polarity of the ciliary rows.


Assuntos
Polaridade Celular/genética , Citoesqueleto/ultraestrutura , Tetrahymena thermophila/genética , Alelos , Animais , Divisão Celular/genética , Cílios/ultraestrutura , Genes de Protozoários , Genes Recessivos , Microscopia Eletrônica , Microtúbulos/ultraestrutura , Mutação , Tetrahymena thermophila/citologia
13.
Dev Biol ; 160(2): 333-54, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8253268

RESUMO

In Tetrahymena, two unique cell-surface structures, the oral apparatus and the cytoproct, are formed at opposite ends of one ciliary row, the reference meridian, which is propagated longitudinally during clonal growth. A third set of unique structures, the contractile vacuole pore(s) (CVP), is located at a nearly constant proportion of the cell circumference to the cell's right of the reference meridian. Three allelic recessive temperature-sensitive mutations, collectively named hypoangular (hpo), alter both the geometry of propagation of the reference meridian and the location of the CVPs. In mutant cells, the reference meridian typically undergoes a steady rightward shift in successive cell generations ("cortical slippage"); concomitantly, CVP sets come to lie closer to the reference meridian. Although CVP location is still proportional to the cell circumference, the constant of proportionality (the "CVP angle") is reduced. Another effect is an alteration in the widths of morphogenetic domains within the cortex. As the temperature is raised (made more restrictive), these effects are accentuated and the CVP angle becomes reduced further. At the extreme, the CVP angle collapses to zero and less, i.e., there is a topological switch such that CVPs come to lie to the left of the reference meridian, and the direction of cortical slippage reverses from rightward to leftward. These observations are hard to reconcile with existing formal models of pattern specification in this system and suggest that the hpo locus might specify a key component of the intracellular positional system.


Assuntos
Genes de Protozoários , Tetrahymena thermophila/genética , Alelos , Animais , Genes Recessivos , Mutação , Temperatura , Tetrahymena thermophila/citologia
14.
Development ; 105(3): 447-56, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2612360

RESUMO

Ciliates exhibit an asymmetry in arrangement of surface structures around the cell which could be termed handedness. If the usual order of placement of structures defines a 'right-handed' (RH) cell, then a cell with this order reversed would be 'left-handed' (LH). Such LH forms appear to be produced in Tetrahymena thermophila through aberrant reorganization of homopolar doublets back to the singlet condition. Four clones of LH forms were selected and subjected to genetic analysis to test whether this drastic phenotypic alteration resulted from a nuclear genetic change. The results of this analysis indicate that the change in handedness is not due to a genetic change in either the micronucleus or macronucleus. The LH form can, under certain circumstances, revert to the RH form, but typically it propagates itself across both vegetative and sexual generations with similar fidelity. While this analysis does not formally rule out certain possibilities of nuclear genic control involving regulatory elements transmitted through the cytoplasm, when the circumstances of origin and propagation of the LH condition are taken into account direct cortical perpetuation seems far more likely. Here we outline a conceptual framework centred on the idea of longitudinally propagated positional information; the positive evidence supporting this idea as well as further application of the idea itself are presented in the accompanying paper.


Assuntos
Núcleo Celular/fisiologia , Tetrahymena/genética , Animais , Células Clonais , Cruzamentos Genéticos , Lateralidade Funcional , Genes , Modelos Biológicos , Fenótipo , Tetrahymena/fisiologia
15.
Diabet Med ; 3(3): 253-6, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-2951180

RESUMO

A District Screening and Treatment Service for diabetic retinopathy using diabetic clinic staff is described. From 1978 to 1984 a total of 1195 diabetics entered the screening programme in a district with a population of 136 700. From 1982, when laser treatment became available locally, the average number of patients from the district requiring treatment for the first time per year was 14.0 for proliferative retinopathy and 11.3 for maculopathy. The laser was also used to treat patients from two other districts and the results of treatment from all three districts are reported. Regression of new vessels was achieved in 86% of 72 patients with proliferative retinopathy but 12 of these were also seen at the regional eye centre. Visual acuity was the same or better in 79% of the 104 eyes in 76 patients treated for maculopathy. Effective treatment can be given by a trained hospital practitioner at district level. This reduces demands on the regional centre but good liaison is necessary for difficult cases.


Assuntos
Retinopatia Diabética/prevenção & controle , Terapia a Laser , Adolescente , Adulto , Idoso , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/cirurgia , Inglaterra , Hospitais de Distrito , Humanos , Macula Lutea , Programas de Rastreamento , Pessoa de Meia-Idade , Ambulatório Hospitalar
16.
Psychol Med ; 15(2): 243-54, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-4023129

RESUMO

A sample of 77 women of high and low noise sensitivity, living in areas of high and low exposure to aircraft noise drawn from the 1977 West London Survey, were interviewed in the community in 1980. Women of high, intermediate and low noise sensitivity in 1980 were compared for measures of psychiatric disorder, personality and reactivity to the other sensory stimuli. In addition, the noise sensitivity measures defining the three groups in 1980 were compared with further measures of noise sensitivity. High noise sensitive women exhibited significantly more psychiatric symptoms, higher neuroticism scores, and greater reactivity to other sensory stimuli than intermediate and low noise sensitive women.


Assuntos
Aeronaves , Transtornos Mentais/psicologia , Ruído dos Transportes/efeitos adversos , Ruído/efeitos adversos , Testes de Personalidade , Adolescente , Adulto , Fatores Etários , Atitude , Feminino , Humanos , Londres , Pessoa de Meia-Idade , Testes Psicológicos , Limiar Sensorial
17.
Psychol Med ; 15(2): 255-63, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-4023130

RESUMO

A sample of 77 women of high and low noise sensitivity in 1977, living in areas of high and low exposure to aircraft noise, were interviewed in the community in 1980. High, intermediate and low noise sensitive women were compared, using measures of blood pressure, heart rate, skin conductance, hearing threshold, uncomfortable loudness level and magnitude estimation of six tones. These physiological measures did not clearly distinguish different noise sensitivity groups, except that highly noise sensitive women had a consistently slower heart rate. Noise sensitivity was not related to auditory threshold. In the high aircraft noise area there were significantly more skin conductance responses than in the low aircraft noise area irrespective of noise sensitivity. This may be the result of chronic exposure to high aircraft noise.


Assuntos
Aeronaves , Nível de Alerta , Ruído dos Transportes/efeitos adversos , Ruído/efeitos adversos , Adolescente , Adulto , Atitude , Limiar Auditivo , Pressão Sanguínea , Feminino , Resposta Galvânica da Pele , Frequência Cardíaca , Humanos , Londres , Percepção Sonora , Pessoa de Meia-Idade , Limiar Sensorial
18.
J Protozool ; 32(1): 126-39, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3989745

RESUMO

The misaligned undulating membrane (mum) mutant of Tetrahymena thermophila is a non-conditional, single gene recessive mutation. The major effect of the mum mutation is the production of multiple undulating membrane (UM) fragments in the oral apparatus (OA). The ultrastructure of the UM fragments of mum OAs is identical to that of the single UM of wild-type OAs. Analysis of OA development at midbody using a combination of light microscopy of protargol-stained cells and SEM of demembranated whole cells showed that the phenotypic effect of the mum mutation first becomes evident during mid to late stage 4 and is fully manifested in early stage 5. The effect of the mutation involves a proliferation of excess basal bodies in the UM field. Subsequent events in the development of the mum OA from mid to late stage 5 are identical to those in wild-type OAs. This study suggests that the mum mutation establishes conditions that allow the production of multiple UMs and thus reveals that the UM field is competent for the complete and coordinated development of several adjacent UMs. This level of regional control is not clearly evident when a single UM is present. The comparison of development of wild-type and mum OAs required an extensive reanalysis of stages 4 and 5 of normal oral development. On the basis of current and previous observations, we propose a new and more subdivided staging system for oral development in Tetrahymena.


Assuntos
Tetrahymena/crescimento & desenvolvimento , Animais , Divisão Celular , Membrana Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Microscopia Eletrônica de Varredura , Microtúbulos/ultraestrutura , Mutação , Fenótipo , Tetrahymena/genética , Tetrahymena/ultraestrutura
19.
J Embryol Exp Morphol ; 82: 41-66, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6491585

RESUMO

The oral apparatus (OA) of the ciliated protozoan Tetrahymena thermophila consists of four ordered arrays of ciliary units. In wild-type cells, these arrays are constant in spatial organization and vary little in size except during extreme starvation. Recessive mutations at five gene loci are known to increase the size of the OA. They do this by increasing the length of the ciliary arrays, without affecting their width and often without increasing their number beyond the usual four. Comparison of the oral arrays over a large range of sizes has revealed: (1) that the lengths of the anterior two of three parallel arrays (membranelles) are rather tightly coordinated; (2) that the specific basal body configurations resulting from remodelling of the membranelles are only slightly affected by large changes in lengths of membranelles; and (3) that the third membranelle is restricted to a nearly constant length, except in the very largest OAs in which the structure is lengthened but interrupted by a gap in the middle. This gap may reveal the spatial extent of a putative zone of basal body regression. These phenomena are not specific to any of the genotypes utilized in this investigation; the effect of the mutations is to loosen quantitative restrictions and thus reveal underlying associations and constraints.


Assuntos
Mutação , Organoides/ultraestrutura , Tetrahymena/genética , Diferenciação Celular , Cílios/ultraestrutura , Membranas Intracelulares/ultraestrutura , Microscopia Eletrônica de Varredura , Fenótipo , Tetrahymena/ultraestrutura
20.
J Embryol Exp Morphol ; 82: 67-95, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6491586

RESUMO

The ciliary arrays of the oral apparatus of the ciliated protozoan Tetrahymena thermophila each have their own unique 'pattern signature', which varies little so long as the number of arrays remains the same. In this study, we analyse the consequence of increases in the number of these arrays (membranelles) brought about by certain mutations. In oral apparatuses of mutant cells, the addition of a membranelle is associated with specific alterations in at least one of the other membranelles. The features that are altered include the relative lengths of membranelles, the state of ciliation of basal bodies located at specific positions within these membranelles, and the spatial configurations resulting from displacement of ciliary units during late oral development. The final organization of each membranelle depends upon its relative position along the length of the oral apparatus. This indicates that the membranelles are not individually 'named' by the organism, and suggests that the unit of pattern organization is the membranelle field as a whole. In the Discussion, we consider means for testing whether the same underlying idea might also apply to multicellular systems, such as the vertebrate limb, in which spatially ordered differences appear to be superimposed upon a fundamental repeating pattern.


Assuntos
Membranas Intracelulares/ultraestrutura , Mutação , Organoides/ultraestrutura , Tetrahymena/genética , Diferenciação Celular , Temperatura Alta , Microscopia Eletrônica de Varredura , Fenótipo , Tetrahymena/ultraestrutura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA