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1.
Phys Chem Chem Phys ; 24(43): 26539-26546, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36305197

RESUMO

In understanding the nature of contrast in the emerging field of neutral helium microscopy, it is important to identify if there is an atom-surface scattering distribution that can be expected to apply broadly across a range of sample surfaces. Here we present results acquired in a scanning helium microscope (SHeM) under typical operating conditions, from a range of surfaces in their native state, i.e. without any specialist sample preparation. We observe diffuse scattering, with an approximately cosine distribution centred about the surface normal. The 'cosine-like' distribution is markedly different from those distributions observed from the well-prepared, atomically pristine, surfaces typically studied in helium atom scattering experiments. Knowledge of the typical scattering distribution in SHeM experiments provides a starting basis for interpretation of topographic contrast in images, as well as a reference against which more exotic contrast mechanisms can be compared.

2.
Aging Ment Health ; 25(7): 1206-1213, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32091237

RESUMO

Engaging with older people who self-identify as lonely may help professionals in mental health and other services understand how they deal with loneliness. The evidence-base for effective interventions to address loneliness is inconclusive. This study aimed to explore how community-dwelling lonely older people in England manage their experiences of loneliness. Twenty eight community-dwelling older people identifying as lonely, based on responses to two loneliness measures (self-report and a standardised instrument), participated in in-depth interviews between 2013 and 2014. Fifteen lived alone. Thematic analysis of transcribed interviews was conducted by a multidisciplinary team including older people.Participants drew on a range of strategies to ameliorate their distress which had been developed over their lives and shaped according to individual coping styles and contexts. Strategies included physical engagement with the world beyond their home, using technologies, planning, and engagement with purpose in an 'outside world', and acceptance, endurance, revealing and hiding, positive attitude and motivation, and distraction within an 'inside world'. Strategies of interests and hobbies, comparative thinking, religion and spirituality and use of alcohol straddled both the inside and outside worlds. Participants conveyed a personal responsibility for managing feelings of loneliness rather than relying on others. This study includes the experiences of those living with loneliness whilst also living with other people. When developing policy and practice responses to loneliness it is important to listen attentively to the views of those who may not be engaging with services designed for 'the lonely' and to consider their own strategies for managing it.


Assuntos
Emoções , Solidão , Idoso , Inglaterra , Humanos , Vida Independente , Pesquisa Qualitativa
3.
J Community Health ; 43(6): 1061-1068, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29770946

RESUMO

Shade in public spaces can lower the risk of and sun burning and skin cancer. However, existing methods of auditing shade require travel between sites, and sunny weather conditions. This study aimed to evaluate the feasibility of free computer software-Google Earth-for assessing shade in urban open spaces. A shade projection method was developed that uses Google Earth street view and aerial images to estimate shade at solar noon on the summer solstice, irrespective of the date of image capture. Three researchers used the method to separately estimate shade cover over pre-defined activity areas in a sample of 45 New Zealand urban open spaces, including 24 playgrounds, 12 beaches and 9 outdoor pools. Outcome measures included method accuracy (assessed by comparison with a subsample of field observations of 10 of the settings) and inter-rater reliability. Of the 164 activity areas identified in the 45 settings, most (83%) had no shade cover. The method identified most activity areas in playgrounds (85%) and beaches (93%) and was accurate for assessing shade over these areas (predictive values of 100%). Only 8% of activity areas at outdoor pools were identified, due to a lack of street view images. Reliability for shade cover estimates was excellent (intraclass correlation coefficient of 0.97, 95% CI 0.97-0.98). Google Earth appears to be a reasonably accurate and reliable and shade audit tool for playgrounds and beaches. The findings are relevant for programmes focused on supporting the development of healthy urban open spaces.


Assuntos
Exposição Ambiental/prevenção & controle , Sistemas de Informação Geográfica , Neoplasias Induzidas por Radiação/prevenção & controle , Exposição à Radiação/prevenção & controle , Luz Solar/efeitos adversos , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Masculino , Nova Zelândia , Exposição à Radiação/normas , Recreação , Reprodutibilidade dos Testes , Estações do Ano
4.
Int J Behav Nutr Phys Act ; 14(1): 137, 2017 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-28988542

RESUMO

BACKGROUND: Over the past three decades the global prevalence of childhood overweight and obesity has increased by 47%. Marketing of energy-dense nutrient-poor foods and beverages contributes to this worldwide increase. Previous research on food marketing to children largely uses self-report, reporting by parents, or third-party observation of children's environments, with the focus mostly on single settings and/or media. This paper reports on innovative research, Kids'Cam, in which children wore cameras to examine the frequency and nature of everyday exposure to food marketing across multiple media and settings. METHODS: Kids'Cam was a cross-sectional study of 168 children (mean age 12.6 years, SD = 0.5) in Wellington, New Zealand. Each child wore a wearable camera on four consecutive days, capturing images automatically every seven seconds. Images were manually coded as either recommended (core) or not recommended (non-core) to be marketed to children by setting, marketing medium, and product category. Images in convenience stores and supermarkets were excluded as marketing examples were considered too numerous to count. RESULTS: On average, children were exposed to non-core food marketing 27.3 times a day (95% CI 24.8, 30.1) across all settings. This was more than twice their average exposure to core food marketing (12.3 per day, 95% CI 8.7, 17.4). Most non-core exposures occurred at home (33%), in public spaces (30%) and at school (19%). Food packaging was the predominant marketing medium (74% and 64% for core and non-core foods) followed by signs (21% and 28% for core and non-core). Sugary drinks, fast food, confectionary and snack foods were the most commonly encountered non-core foods marketed. Rates were calculated using Poisson regression. CONCLUSIONS: Children in this study were frequently exposed, across multiple settings, to marketing of non-core foods not recommended to be marketed to children. The study provides further evidence of the need for urgent action to reduce children's exposure to marketing of unhealthy foods, and suggests the settings and media in which to act. Such action is necessary if the Commission on Ending Childhood Obesity's vision is to be achieved.


Assuntos
Bebidas , Meio Ambiente , Alimentos , Marketing , Meios de Comunicação de Massa , Adolescente , Criança , Estudos Transversais , Etnicidade , Fast Foods , Feminino , Embalagem de Alimentos , Humanos , Masculino , Nova Zelândia , Obesidade Infantil/epidemiologia , Instituições Acadêmicas , Lanches
5.
Psychol Med ; 45(16): 3411-32, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26349810

RESUMO

Depression is one of the most prevalent mental illnesses worldwide and a leading cause of disability, especially in the setting of treatment resistance. In recent years, repetitive transcranial magnetic stimulation (rTMS) has emerged as a promising alternative strategy for treatment-resistant depression and its clinical efficacy has been investigated intensively across the world. However, the underlying neurobiological mechanisms of the antidepressant effect of rTMS are still not fully understood. This review aims to systematically synthesize the literature on the neurobiological mechanisms of treatment response to rTMS in patients with depression. Medline (1996-2014), Embase (1980-2014) and PsycINFO (1806-2014) were searched under set terms. Three authors reviewed each article and came to consensus on the inclusion and exclusion criteria. All eligible studies were reviewed, duplicates were removed, and data were extracted individually. Of 1647 articles identified, 66 studies met both inclusion and exclusion criteria. rTMS affects various biological factors that can be measured by current biological techniques. Although a number of studies have explored the neurobiological mechanisms of rTMS, a large variety of rTMS protocols and parameters limits the ability to synthesize these findings into a coherent understanding. However, a convergence of findings suggest that rTMS exerts its therapeutic effects by altering levels of various neurochemicals, electrophysiology as well as blood flow and activity in the brain in a frequency-dependent manner. More research is needed to delineate the neurobiological mechanisms of the antidepressant effect of rTMS. The incorporation of biological assessments into future rTMS clinical trials will help in this regard.


Assuntos
Antidepressivos/uso terapêutico , Depressão/terapia , Transtorno Depressivo Resistente a Tratamento/terapia , Córtex Pré-Frontal/fisiopatologia , Estimulação Magnética Transcraniana , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Am J Transplant ; 14(8): 1846-52, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25039865

RESUMO

The Renal and Lung Living Donors Evaluation Study assesses outcomes of live lung (lobectomy) donors. This is a retrospective cohort study at University of Southern California (USC) and Washington University (WASHU) Medical Centers (1993­2006), using medical records to assess morbidity and national databases to ascertain postdonation survival and lung transplantation. Serious complications were defined as those that required significant treatment, were potentially life-threatening or led to prolonged hospitalization. The 369 live lung donors (287 USC, 82 WASHU) were predominantly white, non-Hispanic and male; 72% had a biological relationship to the recipient, and 30% were recipient parents. Serious complications occurred in 18% of donors; 2.2% underwent reoperation and 6.5% had an early rehospitalization. The two centers had significantly different incidences of serious complications (p < 0.001). No deaths occurred and no donors underwent lung transplantation during 4000+ person-years of follow-up (death: minimum 4, maximum 17 years; transplant: minimum 5, maximum 19). Live lung donation remains a potential option for recipients when using deceased donor lungs lacks feasibility. However, the use of two live donors for each recipient and the risk of morbidity associated with live lung donation do not justify this approach when deceased lung donors remain available. Center effects and long-term live donor outcomes require further evaluation.


Assuntos
Doadores Vivos/estatística & dados numéricos , Pneumopatias/mortalidade , Pneumopatias/cirurgia , Transplante de Pulmão , Adolescente , Adulto , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Tempo de Internação , Pulmão/cirurgia , Masculino , Pessoa de Meia-Idade , Controle de Qualidade , Projetos de Pesquisa , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
7.
J Eur Acad Dermatol Venereol ; 28 Suppl 1: 1-37, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24354653

RESUMO

BACKGROUND: After the first investigational study on the use of extracorporeal photopheresis for the treatment of cutaneous T-cell lymphoma was published in 1983 with its subsequent recognition by the FDA for its refractory forms, the technology has shown significant promise in the treatment of other severe and refractory conditions in a multi-disciplinary setting. Among the major studied conditions are graft versus host disease after allogeneic bone marrow transplantation, systemic sclerosis, solid organ transplant rejection and inflammatory bowel disease. MATERIALS AND METHODS: In order to provide recognized expert practical guidelines for the use of this technology for all indications the European Dermatology Forum (EDF) proceeded to address these questions in the hands of the recognized experts within and outside the field of dermatology. This was done using the recognized and approved guidelines of EDF for this task. RESULTS AND CONCLUSION: These guidelines provide at present the most comprehensive available expert recommendations for the use of extracorporeal photopheresis based on the available published literature and expert consensus opinion.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Linfoma Cutâneo de Células T/tratamento farmacológico , Fotoferese/estatística & dados numéricos , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Rejeição de Enxerto/tratamento farmacológico , Doença Enxerto-Hospedeiro/tratamento farmacológico , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Fotoferese/métodos , Escleroderma Sistêmico/tratamento farmacológico , Resultado do Tratamento
8.
Ultramicroscopy ; 260: 113951, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38471412

RESUMO

A scanning helium microscope typically utilises a thermal energy helium atom beam, with an energy and wavelength (¡100meV, ∼0.05 nm) particularly sensitive to surface structure. An angular detector stage for a scanning helium microscope is presented that facilitates the in-situ measurement of scattering distributions from a sample. We begin by demonstrating typical elastic and inelastic scattering from ordered surfaces. We then go on to show the role of topography in diffuse scattering from disordered surfaces, observing deviations from simple cosine scattering. In total, these studies demonstrate the wealth of information that is encoded into the scattering distributions obtained with the technique.

9.
Nat Genet ; 25(1): 79-82, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10802661

RESUMO

McKusick-Kaufman syndrome (MKKS, MIM 236700) is a human developmental anomaly syndrome comprising hydrometrocolpos (HMC), postaxial polydactyly (PAP) and congenital heart disease (CHD). MKKS has been mapped in the Old Order Amish population to 20p12, between D20S162 and D20S894 (ref. 3). Here we describe the identification of a gene mutated in MKKS. We analysed the approximately 450-kb candidate region by sample sequencing, which revealed the presence of several known genes and EST clusters. We evaluated candidate transcripts by northern-blot analysis of adult and fetal tissues. We selected one transcript with widespread expression, MKKS, for analysis in a patient from the Amish pedigree and a sporadic, non-Amish case. The Old Order Amish patient was found to be homozygous for an allele that had two missense substitutions and the non-Amish patient was a compound heterozygote for a frameshift mutation predicting premature protein truncation and a distinct missense mutation. The MKKS predicted protein shows amino acid similarity to the chaperonin family of proteins, suggesting a role for protein processing in limb, cardiac and reproductive system development. We believe that this is the first description of a human disorder caused by mutations affecting a putative chaperonin molecule.


Assuntos
Anormalidades Múltiplas/genética , Chaperoninas/genética , Cardiopatias Congênitas/genética , Mutação de Sentido Incorreto/genética , Polidactilia/genética , Anormalidades Urogenitais/genética , Sequência de Aminoácidos , Animais , Criança , Clonagem Molecular , Feminino , Humanos , Lactente , Masculino , Camundongos , Dados de Sequência Molecular , Síndrome
10.
J Intellect Disabil Res ; 55(11): 1020-33, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21554468

RESUMO

BACKGROUND: Many children with Down syndrome do not undertake the recommended amount of daily physical activity. The aim of this study was to explore the barriers and facilitators to physical activity for this group. METHODS: Eighteen in-depth interviews were conducted with 20 parents (16 mothers, 4 fathers) of children with Down syndrome aged between 2 and 17 years to examine what factors facilitate physical activity and what factors are barriers to activity for their children. The participants were recruited through a community disability organisation that advocates for people with Down syndrome and their families. Interviews were recorded, transcribed and independently coded and analysed by two researchers using thematic analysis. RESULTS: Four themes on facilitators of physical activity were identified: (1) the positive role of the family; (2) opportunity for social interaction with peers; (3) structured accessible programmes that make adaptations for children with Down syndrome; and (4) children who were determined to succeed and physically skilled. Four themes on the barriers to physical activity were also identified: (1) characteristics commonly associated with Down syndrome; (2) competing family responsibilities; (3) reduced physical or behavioural skills; and (4) a lack of accessible programmes. CONCLUSIONS: The results highlight the important role of families in determining how much physical activity children with Down syndrome undertake and the effect that common characteristics associated with Down syndrome can have on maintaining an active lifestyle. Future research needs to concentrate on successful methods of encouraging physical activity, such as ensuring social interaction is part of the activity, and eliminating barriers to physical activity such as the a lack of appropriate programmes for children with Down syndrome. Implementing these strategies may encourage children with Down syndrome to participate more frequently in a physically active lifestyle.


Assuntos
Síndrome de Down/fisiopatologia , Síndrome de Down/reabilitação , Atividade Motora/fisiologia , Educação Física e Treinamento , Esportes , Adolescente , Adulto , Criança , Comportamento Infantil , Pré-Escolar , Avaliação da Deficiência , Síndrome de Down/psicologia , Saúde da Família , Feminino , Humanos , Estilo de Vida , Masculino , Motivação , Pais/psicologia , Pesquisa Qualitativa , Esportes/psicologia , Vitória
11.
Ultramicroscopy ; 233: 113453, 2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-35030513

RESUMO

Resolution is a key parameter for microscopy, but methods for standardizing its definition are often poorly defined. For a developing technique such as scanning helium microscopy, it is critical that a consensus-based protocol for determining instrument resolution is prepared as a written standard to allow both comparable quantitative measurements of surface topography and direct comparisons between different instruments. In this paper we assess a range of quantitative methods for determining instrument resolution and determine their relative merits when applied to the specific case of the scanning helium microscope (SHeM). Consequently, we present a preliminary protocol for measuring the resolution in scanning helium microscopy based upon utilizing appropriate test samples with sets of slits of well-defined dimensions to establish the quantitative resolution of any similar instrument.

13.
Am J Transplant ; 10(4 Pt 2): 1047-68, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20420652

RESUMO

This article highlights trends and changes in lung and heart-lung transplantation in the United States from 1999 to 2008. While adult lung transplantation grew significantly over the past decade, rates of heart-lung and pediatric lung transplantation have remained low. Since implementation of the lung allocation score (LAS) donor allocation system in 2005, decreases in the number of active waiting list patients, waiting times for lung transplantation and death rates on the waiting list have occurred. However, characteristics of recipients transplanted in the LAS era differed from those transplanted earlier. The proportion of candidates undergoing lung transplantation for chronic obstructive pulmonary disease decreased, while increasing for those with pulmonary fibrosis. In the LAS era, older, sicker and previously transplanted candidates underwent transplantation more frequently compared with the previous era. Despite these changes, when compared with the pre-LAS era, 1-year survival after lung transplantation did not significantly change after LAS inception. The long-term effects of the change in the characteristics of lung transplant recipients on overall outcomes for lung transplantation remain unknown. Continued surveillance and refinements to the LAS system will affect the distribution and types of candidates transplanted and hopefully lead to improved system efficiency and outcomes.


Assuntos
Transplante de Coração-Pulmão/estatística & dados numéricos , Transplante de Pulmão , Doença Pulmonar Obstrutiva Crônica/mortalidade , Fibrose Pulmonar/cirurgia , Doadores de Tecidos/estatística & dados numéricos , Listas de Espera , Adulto , Criança , Transplante de Coração-Pulmão/mortalidade , Humanos , Pulmão/cirurgia , Transplante de Pulmão/mortalidade , Transplante de Pulmão/estatística & dados numéricos , Transplante de Pulmão/tendências , Doença Pulmonar Obstrutiva Crônica/patologia , Doença Pulmonar Obstrutiva Crônica/cirurgia , Fibrose Pulmonar/epidemiologia , Fibrose Pulmonar/mortalidade , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia
14.
Dig Dis Sci ; 55(5): 1255-63, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19513837

RESUMO

Previous animal and patient-based studies have shown that omeprazole induces a transepithelial paracellular gastric leak. This study reports on the potential for an omeprazole-induced leak of drugs with narrow therapeutic windows. Ussing chamber experiments investigated the effects of omeprazole on rat gastric corpus permeability to the drugs, digoxin and phenytoin. Digoxin (780 MW) permeated the gastric mucosa at an accelerated rate in the presence of omeprazole. This leak could contribute to dangerous elevations of blood digoxin levels in certain situations. Omeprazole was found to have no effect on the flux rate of phenytoin (252 MW). The tight-junctional leak generated by omeprazole thus exhibits specificity to the types of molecules it allows to permeate through the gastric mucosa. This leak may pose a clinical danger by increasing drug uptake into the bloodstream, a phenomenon which would act synergistically with the effect of omeprazole on inhibiting liver cytochrome P450s that remove drugs from the bloodstream, thereby elevating drug blood levels.


Assuntos
Digoxina/farmacologia , Mucosa Gástrica/efeitos dos fármacos , Omeprazol/farmacologia , Inibidores da Bomba de Prótons/farmacologia , Junções Íntimas/efeitos dos fármacos , Animais , Cromatografia em Camada Fina , Eletrofisiologia , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Masculino , Permeabilidade , Fenitoína/farmacologia , Ratos , Ratos Sprague-Dawley
15.
Surg Obes Relat Dis ; 16(11): 1737-1744, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32830059

RESUMO

BACKGROUND: Following bariatric surgery, an explicit dietary regimen is required to facilitate and maintain successful weight loss. Without adequate access to healthy foods, weight maintenance can be hindered. OBJECTIVE: Examine influence degree of food access has on Appalachian bariatric surgery patient weight loss outcomes. SETTING: Appalachian University hospital, United States. METHODS: A retrospective chart review was used to examine the influence of food accessibility on weight loss outcomes in an Appalachian bariatric surgery patient population at a large tertiary hospital in West Virginia between 2013 and 2017. Demographic characteristics, health and family history, and 1-year surgery outcomes were collected. A state-specific food accessibility score was calculated for each patient address using the geographic information system. Patients were assigned a food access ranking score (FARS) between 0 (low food access) and 4 (high food access) based on criteria of quantity, quality, income, and vehicle access. RESULTS: Patients (n = 369) were predominately married (60.5%), white (92.4%), female (77.8%), and underwent laparoscopic Roux-en-Y gastric bypass surgery (75.9%), with a mean age of 45 years. Most patients had low FARS (M = 1.67 ± .73; 72.6%). Nonwhite patients (P = .03) with a preoperative diagnosis of depression (P = .02) or without a family history of obesity (P = .01) were found to be in the lower FARS categories. FARS was not indicative of weight loss post surgery (P > .05). CONCLUSIONS: Food accessibility in West Virginia was not associated with bariatric surgery weight outcomes at 1-year post operation. Lower food access was associated with nonwhite race/ethnicity, diagnosed depression at baseline, and no family history of obesity. Future studies should include more extended follow-up data collection and mixed-method approaches to capture perceptions of food access and its impact on the patients' postoperative journey.


Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Laparoscopia , Obesidade Mórbida , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos , Redução de Peso , West Virginia
17.
Clin Endocrinol (Oxf) ; 70(3): 363-71, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18710464

RESUMO

OBJECTIVE: Evidence suggests that high levels of aldosterone lead to hypertension and increased risk of cardiovascular disease. Around 15% of patients with essential hypertension have a raised aldosterone to renin ratio (ARR) suggesting that aldosterone production is inappropriately high in relation to its principal agonist angiotensin II. This may be due to increased activity of aldosterone synthase caused by genetic variation in the CYP11B2 gene. We screened the coding region of human CYP11B2 for genetic variants and tested their effects on function in vitro. PROTOCOL: Normotensive subjects (n = 69) were screened for sequence variants in the coding region of CYP11B2 by single-stranded conformation polymorphism (SSCP) analysis and sequencing. The effects of nonsynonymous variants on enzyme activity were assessed in JEG-3 cells transiently transfected with wild-type or variant expression plasmids. The conversion of the substrate 11-deoxycorticosterone (DOC) to corticosterone (B) and aldosterone was measured. RESULTS: Twenty variants were detected in CYP11B2 and eight analysed functionally (Arg87Gly, Asn281Thr, Gly288Ser, Lys296Asn, Asp335Asn, Gln404Arg, Ala414Pro and His439Tyr). Corticosterone synthesis was unaltered and aldosterone synthesis reduced in variant Arg87Gly; Asn281Thr increased corticosterone and decreased aldosterone production; Gly288Ser increased corticosterone production and abolished aldosterone production; Lys296Asn reduced both corticosterone and aldosterone production; Asp335Asn increased corticosterone synthesis but did not affect aldosterone production. Variants Gln404Arg, Ala414Pro and His439Tyr showed increases in both corticosterone and aldosterone synthesis compared to the wild-type. CONCLUSION: The study confirms the genetic variability of the CYP11B2 gene and provides us with additional valuable structure-function information.


Assuntos
Citocromo P-450 CYP11B2/genética , Citocromo P-450 CYP11B2/fisiologia , Variação Genética/genética , Adulto , Idoso , Aldosterona/metabolismo , Corticosterona/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Polimorfismo Conformacional de Fita Simples , Análise de Sequência de DNA
18.
Science ; 192(4241): 805-7, 1976 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-1265484

RESUMO

Eight otherwise healthy male chronic marijuana smokers were hospitalized for a period of 30 days. Initially they received placebo, then a sustained dose of 210 milligrams of delta9-tetrahydrocannabinol (delta9-THC) per day for 18 days, followed by placebo. Lymphocyte responses to phytohemagglutinin were examined during each of these periods. Neither the daily ingestion of marijuana extract containing 210 milligrams of delta9-THC for 18 days nor the history of chronic marijuana smoking had a depressive effect on the lymphocyte responses of these subjects to phytohemagglutinin.


Assuntos
Cannabis/farmacologia , Dronabinol/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Adulto , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Lectinas , Masculino , Pessoa de Meia-Idade , Lectinas de Plantas
20.
Respir Physiol Neurobiol ; 164(1-2): 263-71, 2008 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-18692605

RESUMO

The neural network controlling breathing exhibits plasticity in response to environmental or physiological challenges. For example, while hypoxia initiates rapid and robust increases in respiratory motor output to defend against hypoxemia, it also triggers persistent changes, or plasticity, in chemosensory neurons and integrative pathways that transmit brainstem respiratory activity to respiratory motor neurons. Frequently studied models of hypoxia-induced respiratory plasticity include: (1) carotid chemosensory plasticity and metaplasticity induced by chronic intermittent hypoxia (CIH), and (2) acute intermittent hypoxia (AIH) induced phrenic long-term facilitation (pLTF) in naïve and CIH preconditioned rats. These forms of plasticity share some mechanistic elements, although they differ in anatomical location and the requirement for CIH preconditioning. Both forms of plasticity require serotonin receptor activation and formation of reactive oxygen species (ROS). While the cellular sources and targets of ROS are not well known, recent evidence suggests that ROS modify the balance of protein phosphatase and kinase activities, shifting the balance towards net phosphorylation and favoring cellular reactions that induce and/or maintain plasticity. Here, we review possible sources of ROS, and the impact of ROS on phosphorylation events relevant to respiratory plasticity.


Assuntos
Hipóxia/metabolismo , Hipóxia/fisiopatologia , Plasticidade Neuronal/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Humanos , Neurônios Motores/fisiologia , Sistema Respiratório/citologia , Sistema Respiratório/metabolismo
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