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1.
J Hum Nutr Diet ; 31(4): 451-462, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29159932

RESUMO

BACKGROUND: Strong evidence links the consumption of a Mediterranean diet (MD) with a reduced cardiovascular disease (CVD) risk; however, there is uncertainty as to whether non-Mediterranean regions will adopt this diet. The present qualitative research aimed to investigate attitudes towards a MD in individuals at high CVD risk in a Northern European population. This information is needed to inform development of MD interventions in non-Mediterranean high-risk populations. METHODS: Focus groups (n = 12) were held with individuals at high CVD risk from Northern Europe (≥2 CVD risk factors, aged ≥50 years, no established CVD/type 2 diabetes). Attitudes to dietary change towards a MD were explored. Data were analysed using inductive thematic analysis. RESULTS: Sixty-seven adults participated (60% female, mean age 64 years). There was some awareness of the term MD but limited knowledge of its composition. Barriers to general dietary change were evident, including perception of expense, concern over availability, expectation of time commitment, limited knowledge, lack of cooking skills, amount and conflicting nature of media information on diets, changing established eating habits and resistance to dietary change. Barriers specific to MD adoption were also identified, including perceived difficulty living in a colder climate, perceived impact on body weight, acceptability of a MD and cultural differences. CONCLUSIONS: Knowledge of a MD was limited in this Northern European sample at high CVD risk. In addition to general barriers to dietary change, barriers specific to a MD were identified. These findings have implications for the development of interventions aiming to promote MD adoption in non-Mediterranean populations.


Assuntos
Terapia Comportamental/métodos , Doenças Cardiovasculares/prevenção & controle , Dieta Mediterrânea/psicologia , Comportamento Alimentar/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Idoso , Custos e Análise de Custo , Dieta Mediterrânea/economia , Europa (Continente) , Feminino , Grupos Focais , Humanos , Renda , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente/psicologia , Percepção , Fatores de Risco
2.
Gynecol Oncol Rep ; 18: 32-35, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27830172

RESUMO

Basal cell carcinoma (BCC) is the most common non-melanomatous skin cancer, typically arising in sun-exposed areas such as the head and neck. Defective signaling through the Hedgehog (HH) signaling pathway forms the molecular basis for BCC. Surgery remains the mainstay of treatment. Basal cell carcinoma of the genital tract is rare as is metastatic BCC. We report a case of metastatic BCC in a young woman with previously resected vulval BCC presenting six years later with inguinal nodal recurrence and multiple lung metastases.

3.
Soc Sci Med ; 114: 73-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24911510

RESUMO

It is now recognised that inactive lifestyles underpin much of the disease burden evident in the richer nations of the world. Indeed, the WHO has identified physical inactivity as a 'global public health problem' and has established minimum physical activity (PA) targets for people at different stages of the life-course. Yet, according to WHO, just under 1/3 of working age adults across the globe meet those targets and it is not at all clear how the disjunction between the recommendations of policy makers and the behaviour of ordinary people might be surmounted. Using an opportunity to examine the impact of an urban regeneration project on community residents in East Belfast (Northern Ireland) this paper examines the views of some 113 people on how to increase rates of PA in an area of multiple deprivation. The results of the analysis suggest that lay people rarely consider PA as a discrete issue, or one that centres on individuals and their motivation, but rather as one component in a complex web of concerns, processes and events that include such things as the actions of neighbours and relatives, material and political environments, vandalism, violence, and the weather. We explore and unravel the nature of those concerns using novel methods of content analysis that generate 'issue webs'. Particular attention is paid to the ways in which lay people conceptualize 'activity' and to the manner in which they point to ways of encouraging activity that are rooted in everyday life rather than in the corpocentric, agent-centred and often sport dominated strategies favoured by local policy makers. Our results support those who argue that interventions to increase rates of PA need to move beyond behavioural approaches that focus on individuals and consider the social, political and material contexts in which 'activity' occurs.


Assuntos
Promoção da Saúde/métodos , Atividade Motora , Opinião Pública , Adolescente , Adulto , Idoso , Planejamento Ambiental , Feminino , Grupos Focais , Política de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Irlanda do Norte , Áreas de Pobreza , Saúde Pública , Reforma Urbana
4.
Neuroimage ; 80: 190-201, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23702419

RESUMO

The Human Connectome Project (HCP) seeks to map the structural and functional connections between network elements in the human brain. Magnetoencephalography (MEG) provides a temporally rich source of information on brain network dynamics and represents one source of functional connectivity data to be provided by the HCP. High quality MEG data will be collected from 50 twin pairs both in the resting state and during performance of motor, working memory and language tasks. These data will be available to the general community. Additionally, using the cortical parcellation scheme common to all imaging modalities, the HCP will provide processing pipelines for calculating connection matrices as a function of time and frequency. Together with structural and functional data generated using magnetic resonance imaging methods, these data represent a unique opportunity to investigate brain network connectivity in a large cohort of normal adult human subjects. The analysis pipeline software and the dynamic connectivity matrices that it generates will all be made freely available to the research community.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Conectoma/métodos , Magnetoencefalografia/métodos , Modelos Neurológicos , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Humanos , Modelos Anatômicos
5.
J Neurophysiol ; 109(5): 1444-56, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23197455

RESUMO

It has been posited that a critical function of sleep is synaptic renormalization following a net increase in synaptic strength during wake. We hypothesized that wake would alter the resting-state functional organization of the brain and increase its metabolic cost. To test these hypotheses, two experiments were performed. In one, we obtained morning and evening resting-state functional MRI scans to assess changes in functional brain organization. In the second experiment, we obtained quantitative positron emission tomography measures of glucose and oxygen consumption to assess the cost of wake. We found selective changes in brain organization. Most prominently, bilateral medial temporal regions were locally connected in the morning but in the evening exhibited strong correlations with frontal and parietal brain regions involved in memory retrieval. We speculate that these changes may reflect aspects of memory consolidation recurring on a daily basis. Surprisingly, these changes in brain organization occurred without increases in brain metabolism.


Assuntos
Encéfalo/fisiologia , Ritmo Circadiano/fisiologia , Memória , Adulto , Glicemia/análise , Encéfalo/metabolismo , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Consumo de Oxigênio , Tomografia por Emissão de Pósitrons , Sono
6.
Neuroimage ; 62(4): 2222-31, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22366334

RESUMO

The Human Connectome Project (HCP) is an ambitious 5-year effort to characterize brain connectivity and function and their variability in healthy adults. This review summarizes the data acquisition plans being implemented by a consortium of HCP investigators who will study a population of 1200 subjects (twins and their non-twin siblings) using multiple imaging modalities along with extensive behavioral and genetic data. The imaging modalities will include diffusion imaging (dMRI), resting-state fMRI (R-fMRI), task-evoked fMRI (T-fMRI), T1- and T2-weighted MRI for structural and myelin mapping, plus combined magnetoencephalography and electroencephalography (MEG/EEG). Given the importance of obtaining the best possible data quality, we discuss the efforts underway during the first two years of the grant (Phase I) to refine and optimize many aspects of HCP data acquisition, including a new 7T scanner, a customized 3T scanner, and improved MR pulse sequences.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/anatomia & histologia , Encéfalo/fisiologia , Conectoma/métodos , Humanos
7.
Soc Sci Med ; 70(10): 1492-500, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20207462

RESUMO

Translational and transdisciplinary research is needed to tackle complex public health problems. This article has three aims. Firstly, to determine how academics and non-academics (practitioners, policy makers and community workers) identified with the goals of the UKCRC Centre of Excellence for Public Health in Northern Ireland and how their attitudes varied in terms of knowledge brokerage and translation. Secondly, to map and analyse the network structure of the public health sector and the placement of the Centre within this. Thirdly, to aggregate responses from members of the network by work setting to construct the trans-sectoral network and devise the Root Mean Sum of Squares to determine the quality and potential value of connections across this network. The analysis was based on data collected from 98 individuals who attended the launch of the Centre in June 2008. Analysis of participant expectations and personal goals suggests that the academic members of the network were more likely to expect the work of the Centre to produce new knowledge than non-academics, but less likely to expect the Centre to generate health interventions and influence health policy. Academics were also less strongly oriented than non-academics to knowledge transfer as a personal goal, though more confident that research findings would be diffused beyond the immediate network. A central core of five nodes is crucial to the overall configuration of the regional public health network in Northern Ireland, with the Centre being well placed to exert influence within this. Though the overall network structure is fairly robust, the connections between some component parts of the network--such as academics and the third sector--are unidirectional. Identifying these differences and core network structure is key to translational and transdisciplinary research. Though exemplified in a regional study, these techniques are generalisable and applicable to many networks of interest: public health, interdisciplinary research or organisational involvement and stakeholder linkage.


Assuntos
Medicina Baseada em Evidências , Prioridades em Saúde , Saúde Pública , Pesquisa Translacional Biomédica , Medicina Baseada em Evidências/organização & administração , Humanos , Irlanda do Norte , Pesquisa , Apoio Social , Pesquisa Translacional Biomédica/organização & administração
9.
Int J Obes (Lond) ; 32(10): 1585-94, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18725894

RESUMO

OBJECTIVE: Nutrition during critical periods in early life may increase the subsequent risk of obesity, hypertension and metabolic diseases in adulthood. Few studies have focused on the long-term consequences of poor nutrition during the suckling period on the susceptibility to developing obesity when exposed to a palatable cafeteria-style high-fat diet (CD) after weaning. DESIGN: This study examined the impact of early undernutrition, followed by CD exposure, on blood pressure, hormones and genes important for insulin sensitivity and metabolism and skeletal muscle mRNA expression of adiponectin receptor 1 (AdipoR1), carnitine palmitoyl-transferase I (CPT-1), cytochrome c oxidase 4 (COX4) and peroxisome proliferator-activated receptor alpha (PPARalpha). Following normal gestation, Sprague-Dawley rat litters were adjusted to 18 (undernourished) or 12 (control) pups. Rats were weaned (day 21) onto either palatable CD or standard chow. RESULTS: Early undernourished rats were significantly lighter than control by 17 days, persisting into adulthood only when animals were fed chow after weaning. Regardless of litter size, rats fed CD had doubled fat mass at 15 weeks of age, and significant elevations in plasma leptin, insulin and adiponectin. Importantly, undernutrition confined to the suckling period, elevated circulating adiponectin regardless of post-weaning diet. Blood pressure was reduced in early undernourished rats fed chow, and increased by CD. Early undernutrition was associated with long-term elevations in the expression of AdipoR1, CPT-1, COX4 and PPARalpha in skeletal muscle. CONCLUSION: This study demonstrates the important role of early nutrition on body weight and metabolism, suggesting early undernourishment enhances insulin sensitivity and fatty-acid oxidation. The long-term potential benefit of limiting nutrition in the early postnatal period warrants further investigation.


Assuntos
Adiponectina/metabolismo , Dieta , Desnutrição/metabolismo , Músculo Esquelético/metabolismo , Receptores de Adiponectina/metabolismo , Análise de Variância , Animais , Pressão Sanguínea/fisiologia , Distribuição da Gordura Corporal , Carnitina O-Palmitoiltransferase/metabolismo , Ingestão de Energia/fisiologia , Leptina/metabolismo , Desnutrição/fisiopatologia , PPAR alfa/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Desmame
10.
J Intellect Disabil Res ; 51(Pt 9): 726-39, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17845241

RESUMO

BACKGROUND: Dementia is common among adults with Down's syndrome (DS); yet the diagnosis of dementia, particularly in its early stage, can be difficult in this population. One possible reason for this may be the different clinical manifestation of dementia among people with intellectual disabilities. AIMS: The aim of this study was to map out the carers' perspective of symptoms of dementia among adults with DS in order to inform the development of an informant-rated screening questionnaire. METHOD: Unconstrained information from carers of people with DS and dementia regarding the symptoms, particularly the early symptoms of dementia, was gathered using a qualitative methodology. Carers of 24 adults with DS and dementia were interviewed. The interviews were recorded and fully transcribed. The transcripts were then analysed using qualitative software. RESULTS: There appeared to be many similarities in the clinical presentation of dementia in adults with DS and the non-intellectually disabled general population. Like in the non-intellectually disabled general population, forgetfulness especially, impairment of recent memory combined with a relatively intact distant memory and confusion were common, and presented early in dementia among adults with DS. However, many 'frontal lobe'-related symptoms that are usually manifested later in the process of dementia among the general population were common at an early stage of dementia among adults with DS. A general slowness including slowness in activities and speech, other language problems, loss of interest in activities, social withdrawal, balance problems, sleep problems, loss of pre-existing skills along with the emergence of emotional and behaviour problems were common among adults with DS in our study. CONCLUSIONS: This study highlights the similarities in the clinical presentation of dementia among the general population and people with DS with a particular emphasis on the earlier appearance of symptoms associated with the frontal lobe dysfunction among adults with DS.


Assuntos
Demência/epidemiologia , Síndrome de Down/epidemiologia , Adulto , Afeto , Idoso , Humanos , Entrevistas como Assunto , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Transtornos da Personalidade/epidemiologia , Inquéritos e Questionários
12.
Soc Sci Med ; 60(8): 1869-79, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15686817

RESUMO

In the modern era of biomedical practice, genetic knowledge has redefined the idea of 'the patient' to include those who are 'at risk' of disease alongside those who are already sick. For such individuals, it is risk itself that constitutes the raison d'être of medical intervention. Using data from interviews with 58 users of a UK cancer genetics service together with data derived from clinical consultations, we consider the way such patients or clients make sense of a cancer genetic risk estimate and how they integrate genetic risk information into their lifeworld. In particular, we note that patient-clients who are 'at risk' tend to see themselves in a liminal position betwixt the healthy and the sick, and that such individuals consequently seek recourse to systems of medical surveillance that can continuously monitor their state of health. Our analysis also revealed the fact that many of those deemed by professionals to be at low risk of inheriting cancer-related mutations subsequently strove to be re-categorised as being at moderate or high risk of an adverse outcome. A number of explanations concerning lay health beliefs, lay 'representations' of health and the nature of the patient-client's lifeworld are examined and assessed in order to account for this apparent paradox.


Assuntos
Aconselhamento Genético/psicologia , Predisposição Genética para Doença/psicologia , Neoplasias/genética , Neoplasias/psicologia , Atitude Frente a Saúde , Feminino , Aconselhamento Genético/métodos , Humanos , Masculino , Medição de Risco
13.
Br Med Bull ; 57: 207-19, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11719919

RESUMO

How, why, and under what kinds of circumstances lay people consult for symptoms of emotional distress are topics that have commanded various degrees of attention from secondary and primary care professionals. We argue below that many of the responses made by such professionals to these issues carry within them a set of very important assumptions about how members of the lay public view psychiatric symptoms. Whether such assumptions are justified by the evidence is, however, a matter of some debate. In what follows we draw on some recent, sociologically informed research on lay attitudes to emotional distress so as to highlight the debates and to suggest some ways in which they might be resolved.


Assuntos
Sintomas Afetivos/psicologia , Atitude Frente a Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Sintomas Afetivos/terapia , Grupos Focais , Humanos , Relações Médico-Paciente , País de Gales
14.
Biochemistry ; 40(44): 13361-9, 2001 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-11683646

RESUMO

Bacterial nitric oxide reductase (NOR), a member of the superfamily of heme-copper oxidases, catalyzes the two-electron reduction of nitric oxide to nitrous oxide. The key feature that distinguishes NOR from the typical heme-copper oxidases is the elemental composition of the dinuclear center, which contains non-heme iron (FeB) rather than copper (CuB). UV-vis electronic absorption and room-temperature magnetic circular dichroism (RT-MCD) spectroscopies showed that CO binds to Fe(II) heme b3 to yield a low-spin six-coordinate species. Photolysis of the Fe(II)-CO bond is followed by CO recombination (k(on) = 1.7 x 10(8) M(-1) x s(-1)) that is approximately 3 orders of magnitude faster than CO recombination to the active site of typical heme-copper oxidases (k(on) = 7 x 10(4) M(-1)x s(-1)). This rapid rate of CO recombination suggests an unimpeded pathway to the active site that may account for the enzyme's high affinity for substrate, essential for maintaining denitrification at low concentrations of NO. In contrast, the initial binding of CO to reduced heme b3 measured by stopped-flow spectroscopy is much slower (k(on) = 1.2 x 10(5) M(-1) x s(-1)). This suggests that an existing heme distal ligand (water/OH-) may be displaced to elicit the spin-state change observed in the RT-MCD spectrum.


Assuntos
Monóxido de Carbono/metabolismo , Cobre/metabolismo , Oxirredutases/metabolismo , Paracoccus denitrificans/enzimologia , Sítios de Ligação , Divisão Celular , Dicroísmo Circular , Espectroscopia de Ressonância de Spin Eletrônica , Transporte de Elétrons , Elétrons , Heme/química , Heme/metabolismo , Ferro/química , Ferro/metabolismo , Cinética , Ligantes , Oxirredução , Fotólise , Espectrofotometria
15.
Soc Sci Med ; 52(1): 11-23, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11144910

RESUMO

This paper focuses on lay and professional ideas about the nature of chronic fatigue syndrome (CFS), and in particular, the ways in which understandings of the disorder are developed in a clinical setting. Our data are drawn from observations of consultations between sufferers and physicians in a UK medical out-patients clinic. We treat the clinic as a political field. That is to say, as an arena in which 'problems' (about the management of illness) are constituted, and alternative approaches and solutions to such problems are pressed. We note that in the realms of symptoms, aetiology and treatment evaluation, lay people in the CFS clinic have quite distinct ideas about what their problems are and how they might be analysed and managed--ideas that are often in conflict with those of medical professionals. Thus, lay sufferers, for example, operate within a different conceptual terrain from that of many professional experts. They are more likely to refer to a disease (myalgic encephalomyelitis or ME), rather than a syndrome. They call upon different kinds of hypotheses to explain their symptoms. They hold to conflicting ideas about the order of causal sequences, and they give emphasis to different kinds of phenomena in their accounts of illness. As a consequence, clinical consultations can often take on the form of a political contest between physician and patient to define the true and real nature of the patient's disorder--a micro political struggle in which neurological symptoms can be re-framed as psychiatric symptoms, and psychiatric symptoms as neurological. In short, a contest in which the demarcation lines between mind and body are continually assessed and re-defined, and the tenets of 'biomedicine' are constantly challenged.


Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Síndrome de Fadiga Crônica , Relações Médico-Paciente , Anedotas como Assunto , Síndrome de Fadiga Crônica/etiologia , Síndrome de Fadiga Crônica/fisiopatologia , Síndrome de Fadiga Crônica/psicologia , Humanos , Política , Encaminhamento e Consulta , Grupos de Autoajuda , Sociologia Médica , Reino Unido , Instituições Filantrópicas de Saúde
16.
Biochemistry ; 38(42): 13780-6, 1999 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-10529222

RESUMO

Bacterial nitric oxide reductase (NOR) catalyzes the two-electron reduction of nitric oxide to nitrous oxide. It is a highly diverged member of the superfamily of heme-copper oxidases. The main feature by which NOR is distinguished from the heme-copper oxidases is the elemental composition of the active site, a dinuclear center comprised of heme b(3) and non-heme iron (Fe(B)). The visible region electronic absorption spectrum of reduced NOR exhibits a maximum at 551 nm with a distinct shoulder at 560 nm; these are attributed to Fe(II) heme c (E(m) = 310 mV) and Fe(II) heme b (E(m) = 345 mV), respectively. The electronic absorption spectrum of oxidized NOR exhibits a characteristic shoulder around 595 nm that exhibits complex behavior in equilibrium redox titrations. The first phase of reduction is characterized by an apparent shift of the shoulder to 604 nm and a decrease in intensity. This is due to reduction of Fe(B) (E(m) = 320 mV), while the subsequent bleaching of the 604 nm band represents reduction of heme b(3) (E(m) = 60 mV). This separation of redox potentials (>200 mV) allows the enzyme to be poised in the three-electron reduced state for detailed spectroscopic examination of the Fe(III) heme b(3) center. The low midpoint potential of heme b(3) represents a thermodynamic barrier to the complete (two-electron) reduction of the dinuclear center. This may avoid formation of a stable Fe(II) heme b(3)-NO species during turnover, which may be an inhibited state of the enzyme. It would also appear that the evolution of significant oxygen reducing activity by heme-copper oxidases was not simply a matter of the substitution of copper for non-heme iron in the dinuclear center. Changes in the protein environment that modulate the midpoint redox potential of heme b(3) to facilitate both complete reduction of the dinuclear center (a prerequisite for oxygen binding) and rapid heme-heme electron transfer were also necessary.


Assuntos
Cobre/química , Heme/química , Oxirredutases/química , Dicroísmo Circular , Cobre/metabolismo , Grupo dos Citocromos b/química , Grupo dos Citocromos c/química , Espectroscopia de Ressonância de Spin Eletrônica , Transporte de Elétrons , Heme/metabolismo , Oxirredução , Oxirredutases/metabolismo , Paracoccus denitrificans/enzimologia , Potenciometria , Espectrofotometria
17.
Genes Dev ; 13(17): 2301-14, 1999 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10485851

RESUMO

Cytokinesis ensures the successful completion of the cell cycle and distribution of chromosomes, organelles, and cytoplasm between daughter cells. It is accomplished by formation and constriction of an actomyosin contractile ring that drives the progression of a cleavage furrow. Microinjection experiments and in vitro transfection assays have suggested a requirement for small GTPases of the Rho family in cytokinesis. Yet, the identity of proteins regulating Rho signaling pathways during cytokinesis remains unknown. Here we show that in Drosophila, Pebble (Pbl), a putative exchange factor for Rho GTPases (RhoGEF), is required for the formation of the contractile ring and initiation of cytokinesis. The dynamics of Pbl expression and its distribution during mitosis, as well as structure-function analysis, indicate that it is a key regulatory component of the pathway. pbl interacts genetically with Rho1, but not with Rac1 or Cdc42, and Pbl and Rho1 proteins interact in vivo in yeast. Similar to mutations in pbl, loss of Rho1 or expression of a dominant-negative Rho1 blocks cytokinesis. Our results identify Pbl as a RhoGEF specifically required for cytokinesis and linked through Rho1 activity to the reorganization of the actin cytoskeleton at the cleavage furrow.


Assuntos
Ciclo Celular/fisiologia , Drosophila melanogaster/fisiologia , GTP Fosfo-Hidrolases/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas/genética , Proteínas/metabolismo , Proteínas rho de Ligação ao GTP , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Divisão Celular , Cromossomos/fisiologia , Cromossomos/ultraestrutura , Clonagem Molecular , Citoplasma/fisiologia , Citoplasma/ultraestrutura , Proteínas de Drosophila , Drosophila melanogaster/citologia , Drosophila melanogaster/genética , Microscopia Eletrônica de Varredura , Mitose , Dados de Sequência Molecular , Organelas/fisiologia , Organelas/ultraestrutura , Proteínas/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transdução de Sinais
18.
Immunology ; 94(3): 403-9, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9767424

RESUMO

B-cell heterogeneity studies have historically focused upon BALB/c mice and their derivatives. In contrast, the B cells of DBA/2J mice, a prototype strain for the study of the endogenous minor lymphocyte stimulatory (Mls) viral superantigen Mls-1a, have not been extensively investigated. DBA/2J B cells, by functioning as Mls-1a antigen-presenting cells, influence their own differentiation and diversity by inducing the proliferation and differentiation of specific CD4 T-cell subsets. In this report, the B cells of DBA/2J and BALB/c mice were compared for their ability to restore B-cell function in severe combined immunodeficient (SCID) recipients. Although spleen and bone marrow cells from these strains exhibited similar restoration of serum IgM production, the transfer of DBA/2J B cells into SCID mice led to greater IgG1 production. The peritoneal cells of DBA/2J mice consisted of a lower percentage of B-1 B cells and were less capable of restoring B-cell function after transfer into SCID recipients. These differences are discussed with respect to the possible role of viral superantigens in influencing B-lymphocyte diversity.


Assuntos
Transferência Adotiva , Subpopulações de Linfócitos B/imunologia , Imunoglobulina G/sangue , Camundongos Endogâmicos DBA/imunologia , Imunodeficiência Combinada Severa/imunologia , Imunodeficiência Combinada Severa/terapia , Animais , Linfócitos B/imunologia , Citometria de Fluxo , Imunoglobulina M/sangue , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Peritônio/imunologia , Retroviridae/imunologia , Superantígenos/imunologia , Linfócitos T/imunologia
19.
Immunology ; 91(3): 383-90, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9301527

RESUMO

In vivo studies of lymphocyte biology have used intravenous (i.v.) injection as the primary mode of cell transfer, a protocol consistent with the anatomic distribution of most lymphocytes. However, for study of peritoneal cavity B cells, i.v. injection does not correlate with anatomical localization. This report describes the restoration of B-cell function in B lymphocyte-defective X-chromosome-linked immune-defective (XID) mice after intraperitoneal transfer of immunoglobulin heavy chain (Igh)-disparate peritoneal cavity (PerC) cells. In contrast to i.v. transfer, intraperitoneal (i.p.) transfer restored B-cell function in young, but not adult (> 8 weeks), XID mice. When host and donor Igh allotype matched, PerC B-cell engraftment was noted in older recipients; this reconstitution however, was also age-dependent. Migration from the peritoneum to systemic circulation was necessary for serum IgM production as shown by the presence of donor antibody-secreting cells in the host spleen. Host lymphocytes also influenced the success of i.p. transplantation as severe combined immune-deficient mice, regardless of age, exhibited donor serum IgM production. Recipient age, Igh allotype, and immune-deficiency were found to have an impact on the ability of i.p.-transferred PerC B cells to restore B-cell function in XID mice.


Assuntos
Envelhecimento/imunologia , Subpopulações de Linfócitos B/imunologia , Síndromes de Imunodeficiência/terapia , Transfusão de Linfócitos , Cavidade Peritoneal/citologia , Animais , Subpopulações de Linfócitos B/transplante , Imunoglobulina M/biossíntese , Injeções Intraperitoneais , Injeções Intravenosas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Baço/imunologia
20.
Br J Gen Pract ; 47(424): 739-42, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9519524

RESUMO

Measures of risk frequently contribute to our understanding, prevention, or treatment of disease, but it is important that general practitioners (GPs) explain clinical risks effectively to patients to ensure they are not misunderstood, as risk information can assist in decision-making processes and encourage behavioural change. However, the interpretation of risks by patients and doctors varies. It is argued that problems arise because communication about risk is usually framed in terms of the language of chance or probability. In this paper, we describe how probability theory developed, and suggest that attempts to communicate empirical risk processes in probabilistic language are bound to produce dilemmas. We explore how the theory relates to clinical practice and identify key issues that doctors must address in discussing risk with individual patients.


Assuntos
Comunicação , Medicina de Família e Comunidade , Humanos , Relações Médico-Paciente , Probabilidade , Risco , Revelação da Verdade
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