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1.
Geophys Res Lett ; 49(15): e2022GL098616, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36247515

RESUMO

A geomagnetic jerk was seen in Swarm satellite data in 2017 over the Pacific region. We invert time series of spatial gradient secular variation data between 2014 and 2020, reduced to a grid of points at satellite altitude, for spatially- and temporally-regularized core surface flow. Pacific region flow acceleration was almost constant before and after the jerk, with a sharp change, especially in the azimuthal component, at the jerk epoch, despite the temporal regularization. Azimuthal acceleration is oppositely signed either side of 160°W, where it effectively vanishes, and also reverses sign at the jerk epoch. Acceleration features drift westward at about 900 km year-1. Unlike previous studies, the evidence presented here for low latitude waves does not depend on imposing flow equatorial symmetry, quasi- or tangential geostrophy, or band-pass filtering, and has no reliance on stochastic models or numerical simulations.

2.
Lupus ; 28(5): 575-582, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30952199

RESUMO

Systemic lupus erythematosus (SLE) is a chronic inflammatory disease with immune system disorder mediated through complex autoimmune pathways that involve immune cells, nonimmune cells, cytokines, chemokines, as well as costimulatory molecules. Costimulatory signals play a critical role in initiating, maintaining and regulating immune reactions, and these include ligands and receptors and their interactions involving multiple types of signal information. Dysfunction of costimulatory factors results in complicated abnormal immune responses, with biological effects and eventually, clinical autoimmune diseases. Here we outline what is known about various roles that costimulatory families including the B7 family and tumor necrosis factor super family play in SLE. The aim of this review is to understand the possible association of costimulation with autoimmune diseases, especially SLE, and to explore possible therapeutic target(s) of costimulatory molecules and pathways that might be used to develop therapeutic approaches for patients with these conditions.


Assuntos
Antígenos B7/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Transdução de Sinais , Fatores de Necrose Tumoral/imunologia , Comunicação Celular/imunologia , Humanos , Ativação Linfocitária
3.
Int J Obes (Lond) ; 42(1): 59-64, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28883538

RESUMO

BACKGROUND: Inadequate sleep has been shown to be a contributor to obesity in both children and adults. Less evidence is available for toddlers and among those with higher obesity risk. The objective of this study was to examine the relationship between sleep patterns and body weight development in a group of young obesity-predisposed children, and to assess whether intakes of energy or macronutrients mediate this relationship. METHODS: Participants included 368 Danish children aged 2-6 years from the Healthy Start Study, a 1.3 year randomised controlled intervention trial. Sleep habits were measured using a 7-day sleep diary. Multivariate linear regression with adjustment for confounders was used to assess the association of sleep duration and sleep variability with 1.3 year changes (Δ) in body mass index (BMI) z-score from baseline to follow-up. RESULTS: The average nighttime sleep duration was 10.7 h (range 8.8-12.5 h). After controlling for potential confounders, a significant inverse association between nighttime sleep duration and ΔBMI z-score (ß=-0.090, P=0.046) was observed. This relationship was mediated by energy intake, with all macronutrients contributing to this mediation effect. No associations were found for sleep variability and ΔBMI z-score but baseline intake of added sugars and sugary beverages were positively associated with sleep variability. CONCLUSION: Shorter sleep duration, mediated by energy intake in early in life, seems a risk factor for weight gain among young obesity-predisposed children.


Assuntos
Peso Corporal/fisiologia , Ingestão de Energia/fisiologia , Sobrepeso/epidemiologia , Sono/fisiologia , Índice de Massa Corporal , Criança , Pré-Escolar , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Fatores de Tempo
4.
Clin Exp Immunol ; 192(1): 68-81, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29205315

RESUMO

Repository corticotrophin injection (RCI, H.P Acthar® gel) has been approved for use in the management of multiple autoimmune and inflammatory diseases for more than a half-century, but its mechanism of action is not well understood. We used RNA-Seq methods to define RCI-regulated mRNAs in cultured human B cells under conditions of activation by interleukin (IL)-4 and CD40 ligand. Following IL-4/CD40L activation and RCI treatment we found up-regulation of 115 unique mRNA transcripts and down-regulation of 80 unique mRNAs. The effect on these RNA levels was dose-dependent for RCI and was distinct from changes in mRNA expression induced by treatment with a potent synthetic glucocorticoid. RCI down-regulated mRNAs were observed to include a significant over-representation of genes critical for B cell proliferation under activating conditions. These data confirm that RCI exerts direct effects on human B cells to modulate mRNA expression in specific pathways of importance to B cell function and that, at the molecular level, the effects of RCI are distinct from those exerted by glucocorticoids.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Linfócitos B/efeitos dos fármacos , Expressão Gênica , RNA Mensageiro/genética , Adulto , Idoso , Ligante de CD40/farmacologia , Regulação para Baixo , Feminino , Glucocorticoides/farmacologia , Humanos , Interleucina-4/farmacologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Análise de Sequência de RNA , Regulação para Cima
5.
J Autoimmun ; 81: 99-109, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28420548

RESUMO

Genome-wide association studies have identified numerous genetic variants conferring autoimmune disease risk. Most of these genetic variants lie outside protein-coding genes hampering mechanistic explorations. Numerous mRNAs are also differentially expressed in autoimmune disease but their regulation is also unclear. The majority of the human genome is transcribed yet its biologic significance is incompletely understood. We performed whole genome RNA-sequencing [RNA-seq] to categorize expression of mRNAs, known and novel long non-coding RNAs [lncRNAs] in leukocytes from subjects with autoimmune disease and identified annotated and novel lncRNAs differentially expressed across multiple disorders. We found that loci transcribing novel lncRNAs were not randomly distributed across the genome but co-localized with leukocyte transcriptional enhancers, especially super-enhancers, and near genetic variants associated with autoimmune disease risk. We propose that alterations in enhancer function, including lncRNA expression, produced by genetics and environment, change cellular phenotypes contributing to disease risk and pathogenesis and represent attractive therapeutic targets.


Assuntos
Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Autoimunidade/genética , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Variação Genética , RNA Longo não Codificante/genética , Adulto , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/terapia , Biomarcadores , Estudos de Casos e Controles , Biologia Computacional/métodos , Suscetibilidade a Doenças , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Risco
6.
Eur J Neurol ; 24(2): 412-418, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28000311

RESUMO

BACKGROUND AND PURPOSE: Subcutaneous immunoglobulin (SCIG) is effective as maintenance treatment in chronic inflammatory demyelinating polyneuropathy (CIDP). We investigated whether multiple subcutaneous infusions are as effective as conventional therapy with intravenous loading doses in treatment-naive patients with CIDP. METHODS: Twenty patients fulfilling the clinical and electrophysiological criteria for CIDP were included and treated with either SCIG (0.4 g/kg/week) for 5 weeks or intravenous immunoglobulin (IVIG) (0.4 g/kg/day) for 5 days. After 10 weeks, patients were switched to the opposite treatment arm and followed for a further 10 weeks. All participants were evaluated at weeks 0, 2, 5 and 10 during both therapies. Primary outcome was combined isokinetic muscle strength (cIKS). Secondary outcomes were disability, clinical evaluation of muscle strength and the performance of various function tests. RESULTS: All participants received both therapies, 14 completing the protocol. Overall, cIKS increased by 7.4 ± 14.5% (P = 0.0003) during SCIG and by 6.9 ± 16.8% (P = 0.002) during IVIG, the effect being similar (P = 0.80). Improvement of cIKS peaked 2 weeks after IVIG and 5 weeks after SCIG. Disability improved during SCIG treatment only. Muscle strength determined by manual muscle testing improved after 5 and 10 weeks during SCIG but only after 5 weeks during IVIG. The remaining parameters improved equally during both treatments. Plasma immunoglobulin G levels at baseline and improvement of cIKS were related. CONCLUSION: In treatment-naive patients with CIDP, short-lasting SCIG and IVIG therapy improve motor performance to a similar degree, but with earlier maximal improvement following IVIG than SCIG treatment.


Assuntos
Imunoglobulinas/administração & dosagem , Imunoglobulinas/uso terapêutico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/tratamento farmacológico , Adulto , Idoso , Estudos Cross-Over , Avaliação da Deficiência , Feminino , Humanos , Imunoglobulina G/análise , Imunoglobulinas Intravenosas/uso terapêutico , Infusões Subcutâneas , Masculino , Pessoa de Meia-Idade , Força Muscular , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Método Simples-Cego , Resultado do Tratamento
7.
Occup Environ Med ; 73(11): 749-752, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27542398

RESUMO

BACKGROUND: Malignant mesothelioma (MM) has distinct histological subtypes (epithelioid, sarcomatoid and biphasic) with variable behaviour and prognoses. It is well recognised that survival time varies with the histological subtype of MM. It is not known, however, if asbestos exposure characteristics (type of asbestos, degree of exposure) are associated with different histological subtypes. AIM: To determine if the pathological MM subtype is associated with the type of asbestos or the attributes of asbestos exposure. METHODS: Cases of MM for the period 1962 until 2012, their main histological subtype and their most significant source of asbestos exposure were collected from the Western Australian Mesothelioma Registry. Exposure characteristics included, degree of asbestos exposure (including total days exposed, years since first exposure and, for crocidolite only, calculated cumulative exposure), source of exposure (occupational or environmental), form of asbestos handled (raw or processed) and type of asbestos (crocidolite only or mixed fibres). RESULTS: Patients with the biphasic subtype were more likely to have occupational exposure (OR 1.83, 1.12 to 2.85) and exposure to raw fibres (OR 1.58, 1.19 to 2.10). However, differences between subtypes in the proportions with these different exposure characteristics were small and unlikely to be biologically relevant. Other indicators of asbestos exposure were not associated with the histological subtype of mesothelioma. CONCLUSIONS: There was no strong evidence of a consistent role of asbestos exposure indicators in determining the histological subtype of MM.


Assuntos
Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/patologia , Mesotelioma/induzido quimicamente , Mesotelioma/patologia , Exposição Ocupacional/efeitos adversos , Idoso , Amianto , Asbesto Crocidolita/efeitos adversos , Humanos , Modelos Logísticos , Masculino , Mesotelioma Maligno , Pessoa de Meia-Idade , Mineração , Doenças Profissionais/induzido quimicamente , Doenças Profissionais/patologia , Prognóstico , Sistema de Registros , Inquéritos e Questionários , Austrália Ocidental
9.
Scand J Med Sci Sports ; 25(3): e253-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25142912

RESUMO

Free diving is associated with extreme hypoxia. This study evaluated the combined effect of maximal static breath holding and underwater swimming on plasma biomarkers of tissue hypoxemia: erythropoietin, neuron-specific enolase and S100B, C-reactive protein, pro-atrial natriuretic peptide, and troponin T. Venous blood samples were obtained from 17 competing free divers before and 3 h after sessions of static apnea and underwater swimming. The heart was evaluated by echocardiography. Static apnea for 293 ± 78 s (mean ± SD) and subsequent 88 ± 21 m underwater swimming increased plasma erythropoietin from 10.6 ± 3.4 to 12.4 ± 4.1 mIU/L (P = 0.013) and neuron-specific enolase from 14.5 ± 5.3 to 24.6 ± 6.4 ng/mL (P = 0.017); C-reactive protein decreased from 0.84 ± 1.0 to 0.71 ± 0.67 mmol/L (P = 0.013). In contrast, plasma concentrations of S100B (P = 0.394), pro-atrial natriuretic peptide (P = 0.549), and troponin T (P = 0.125) remained unchanged and, as assessed by echocardiography, the heart was not affected. In competitive free divers, bouts of static and dynamic apnea increase plasma erythropoietin and neuron-specific enolase, suggesting that renal and neural tissue, rather than the heart, is affected by the hypoxia developed during apnea and underwater swimming.


Assuntos
Adaptação Fisiológica/fisiologia , Suspensão da Respiração , Mergulho , Coração/fisiologia , Hipóxia/sangue , Fosfopiruvato Hidratase/sangue , Adulto , Atletas , Fator Natriurético Atrial/sangue , Proteína C-Reativa/metabolismo , Ecocardiografia , Eritropoetina/sangue , Feminino , Humanos , Masculino , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Natação , Troponina T/sangue
10.
Br J Anaesth ; 112(2): 311-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24085770

RESUMO

BACKGROUND: Endothelial dysfunction might be involved in the development of cerebral vasospasm after aneurysmal subarachnoid haemorrhage (SAH). METHODS: This prospective observational study of 48 SAH subjects and 23 control subjects examined associations between reactive hyperaemia index (RHI) measured by peripheral arterial tonometry and plasma concentrations of S-100B protein, nitrite/nitrate, arginine, and asymmetric dimethyl arginine (ADMA). Clinical variables were flow velocity in the middle cerebral artery (VMCA), angiographic vasospasm, delayed neurological deficit, and 30 day survival. Five consecutive measurements were obtained at days 0-2, 3-5, 6-8, 9-11, and 12-15. RESULTS: RHI was 1.67 (0.46) at days 0-2 after SAH but increased at days 3-15 to the same levels as in controls (P<0.05 compared with days 0-2). RHI was lower in subjects who died before day 30 (P=0.07), but no trends were observed in relation to angiographic vasospasm or delayed neurological deficit. Both arginine and ADMA increased after SAH compared with days 0-2 (P<0.05). S-100B was highest in non-survivors (P<0.01) and in subjects with neurological deficit (P<0.01). A positive correlation was found between RHI and arginine:ADMA ratio (r=0.43, P<0.005), but not with nitrite/nitrate, VMCA, or S-100B. CONCLUSIONS: Peripheral flow-mediated vasodilation is attenuated in the first days after SAH indicating acute systemic endothelial dysfunction. Impairment of endothelial function after SAH correlates with imbalance of the arginine/ADMA pathway.


Assuntos
Arginina/análogos & derivados , Arginina/sangue , Endotélio/fisiopatologia , Hemorragia Subaracnóidea/sangue , Adulto , Biomarcadores/sangue , Velocidade do Fluxo Sanguíneo/fisiologia , Feminino , Seguimentos , Humanos , Hiperemia/sangue , Hiperemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Sobrevida , Vasoespasmo Intracraniano/sangue
11.
Br J Anaesth ; 113(3): 452-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24508985

RESUMO

BACKGROUND: Phenylephrine and ephedrine affect frontal lobe oxygenation ([Formula: see text]) differently when assessed by spatially resolved near infrared spectroscopy. We evaluated the effect of phenylephrine and ephedrine on extra- vs intra-cerebral blood flow and on [Formula: see text]. METHODS: In 10 healthy males (age 20-54 yr), phenylephrine or ephedrine was infused for an ∼20 mm Hg increase in mean arterial pressure. Cerebral oxygenation (SavO2) was calculated from the arterial and jugular bulb oxygen saturations. Blood flow in the internal carotid artery (ICAf) and blood flow in the external carotid artery (ECAf) were assessed by duplex ultrasonography. Invos-5100c (SinvosO2) and Foresight (SforeO2) determined [Formula: see text] while forehead skin oxygenation (SskinO2) was assessed. RESULTS: Phenylephrine reduced SforeO2 by 6.9% (95% confidence interval: 4.8-9.0%; P<0.0001), SinvosO2 by 10.5 (8.2-12.9%; P<0.0001), and ECAf (6-28%; P=0.0001), but increased ICAf (5-21%; P=0.003) albeit with no consequence for SskinO2 or SavO2. In contrast, SforeO2 was maintained with administration of ephedrine while SinvosO2 and SavO2 decreased [by 3.1 (0.7-4.5%; P=0.017) and 2.1 (0.5-3.3%; P=0.012)] as arterial carbon dioxide pressure decreased (P=0.003). ICAf was stable and ECAf increased by 11 (4-18%; P=0.005) with administration of ephedrine while SskinO2 did not change. CONCLUSIONS: The effect of phenylephrine on ScO2 is governed by a decrease in external carotid blood flow since it increases cerebral blood flow as determined by flow in the internal carotid artery. In contrast, ScO2 is largely maintained with administration of ephedrine because blood flow to extracerebral tissue increases.


Assuntos
Artéria Carótida Externa/efeitos dos fármacos , Artéria Carótida Externa/metabolismo , Efedrina/farmacologia , Lobo Frontal/efeitos dos fármacos , Oxigênio/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adrenérgicos/farmacologia , Adulto , Lobo Frontal/irrigação sanguínea , Lobo Frontal/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
12.
Osteoporos Int ; 24(4): 1285-93, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22986930

RESUMO

UNLABELLED: Uncertainty remains over whether or not high intakes of retinol or vitamin A consumed through food or supplements may increase fracture risk. This intervention study found no increase in fracture risk among 2,322 adults who took a controlled, high-dose retinol supplement (25,000 IU retinyl palmitate/day) for as long as 16 years. There was some evidence that beta-carotene supplementation decreased fracture risk in men. INTRODUCTION: There is conflicting epidemiological evidence regarding high intakes of dietary or supplemental retinol and an increased risk for bone fracture. We examined fracture risk in a study administering high doses of retinol and beta-carotene (BC) between 1990 and 2007. METHODS: The Vitamin A Program was designed to test the efficacy of retinol and BC supplements in preventing malignancies in persons previously exposed to blue asbestos. Participants were initially randomised to 7.5 mg retinol equivalents (RE)/day as retinyl palmitate, 30 mg/day BC or 0.75 mg/day BC from 1990 to 1996; after which, all participants received 7.5 mg RE/day. Fractures were identified by questionnaire and hospital admission data up until 2006. Risk of any fracture or osteoporotic fracture according to cumulative dose of retinol and BC supplementation was examined using conditional logistic regression models adjusting for age, sex, smoking, body mass index, medication use and previous fracture. RESULTS: Supplementation periods ranged from 1 to 16 years. Of the 2,322 (664 females and 1,658 males) participants, 187 experienced 237 fractures. No associations were observed between cumulative dose of retinol and risk for any fracture (OR per 10 g RE=0.83; 95% CI, 0.63-1.08) or osteoporotic fracture (OR per 10 g RE=0.95; 95% CI 0.64-1.40). Among men, cumulative dose of BC was associated with a slightly reduced risk of any fracture (OR per 10 g=0.89; 95% CI 0.81-0.98) and osteoporotic fracture (OR per 10 g=0.84; 95% CI 0.72-0.97). CONCLUSIONS: This study observed no increases in fracture risk after long-term supplementation with high doses of retinol and/or beta-carotene.


Assuntos
Suplementos Nutricionais/efeitos adversos , Fraturas por Osteoporose/induzido quimicamente , Vitamina A/análogos & derivados , beta Caroteno/efeitos adversos , Adulto , Idoso , Diterpenos , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Incidência , Neoplasias Pulmonares/prevenção & controle , Masculino , Mesotelioma/prevenção & controle , Pessoa de Meia-Idade , Doenças Profissionais/prevenção & controle , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Ésteres de Retinil , Medição de Risco/métodos , Vitamina A/administração & dosagem , Vitamina A/efeitos adversos , Vitamina A/uso terapêutico , Austrália Ocidental/epidemiologia , beta Caroteno/administração & dosagem , beta Caroteno/uso terapêutico
13.
Eur J Neurol ; 20(5): 836-42, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23294032

RESUMO

BACKGROUND AND PURPOSE: We hypothesized that subcutaneous administration of immunoglobulins (SCIG) in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is feasible, safe and superior to treatment with saline for the performance of muscle strength. METHODS: Thirty patients with motor involvement in maintenance therapy with intravenous immunoglobulin (IVIG) fulfilling the EFNS/PNS criteria for CIDP, aged 18-80 years, were randomized either to SCIG at a dose corresponding to their pre-study IVIG dose or to subcutaneous saline given twice or thrice weekly for 12 weeks at home. At the start and end of the trial as well as 2 weeks before (-2, 0, 10, 12 weeks), isokinetic strength performance of four predetermined and weakened muscle groups was measured. Also, an Overall Disability Sum Score (ODSS), 40-m-walking test (40-MWT), nine-hole-peg test, Neurological Impairment Score (NIS), Medical Research Council (MRC) score, grip strength, standardized electrophysiological recordings from three nerves, and plasma IgG levels were evaluated. RESULTS: SCIG treatment was well tolerated in all 14 patients. Six patients complained of mild side-effects at the injection site. In the SCIG group there was an increase of isokinetic muscle strength of 5.5 ± 9.5% (P < 0.05) as compared with a decline of 14.4 ± 20.3% (P < 0.05) in the placebo group; the difference between the two groups being significant (P < 0.01). ODSS, NIS, MRC, grip strength and 40-MWT improved following SCIG versus saline. CONCLUSIONS: SCIG treatment in CIDP is feasible, safe and effective, and seems an attractive alternative to IVIG.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Imunoglobulinas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Força Muscular/efeitos dos fármacos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/tratamento farmacológico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Avaliação da Deficiência , Método Duplo-Cego , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulinas/administração & dosagem , Imunoglobulinas/sangue , Imunoglobulinas Intravenosas/farmacocinética , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/farmacocinética , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Força Muscular/fisiologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/sangue
14.
Br J Anaesth ; 110(4): 577-85, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23257989

RESUMO

BACKGROUND: Transcranial Doppler measurements of the middle cerebral artery flow velocity are widely used as an indicator of vasospasm after aneurysmal subarachnoid haemorrhage (SAH). We investigated inter- and intraoperator agreement in SAH patients and healthy volunteers using colour-coded transcranial Doppler (TCCD), with the secondary aim of describing prediction of angiographic vasospasm and mortality. METHODS: Sixty patients and 70 healthy controls were each examined in duplicate by alternating operators. A total of 939 measurements divided on 201 examination sets were conducted by four observers. The Bland-Altman limits of agreement (LoA) were calculated using a variance components analysis. Angiography was performed on clinical indication and survival recorded at 30 days. RESULTS: Differences between measurements increased with increasing average, and therefore, we analysed log-transformed values. Thus, LoA are given as ratios between measurements. There were no systematic intra- or interobserver differences (bias). The intraobserver LoA was 0.62-1.61 in patients and 0.67-1.50 in controls. However, they were 0.55-1.82 in patients with angiographic vasospasm, whereas in patients without, they were 0.66-1.52. The interobserver LoA was 0.55-1.81 in patients and 0.65-1.55 in controls, while in patients with and without angiographic vasospasm, they were 0.45-2.22 and 0.60-1.67, respectively. Flow velocity measurements day 6-10 were positively associated with 30 day mortality risk (P=0.02, logistic regression). CONCLUSIONS: TCCD measurement variability is wider in patient measurements than in controls. This discrepancy can largely be explained by a higher degree of error in patients with angiographic vasospasm. Despite the considerable measurement variability in TCCD, values are predictive of outcome in SAH.


Assuntos
Circulação Cerebrovascular/fisiologia , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/fisiopatologia , Vasoespasmo Intracraniano/diagnóstico por imagem , Vasoespasmo Intracraniano/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Angiografia Digital , Angiografia Cerebral , Feminino , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/fisiopatologia , Variações Dependentes do Observador , Estudos Prospectivos , Hemorragia Subaracnóidea/mortalidade , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler Transcraniana , Vasoespasmo Intracraniano/mortalidade , Adulto Jovem
15.
Br J Anaesth ; 110(5): 741-6, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23257992

RESUMO

BACKGROUND: Over a 5 yr period, we have encountered three patients in whom remifentanil appeared to have no clinical effect during general anaesthesia (GA). We describe seven anaesthetics in these three patients. METHODS: We reviewed the literature on this subject. A simple reproducible test to explore this response was designed. This involved a controlled infusion of increasing doses of remifentanil while observing respiratory variables, pain threshold, pupil size, and Glasgow coma scale score. In addition, blood was sampled for genotyping. RESULTS: No description of this impaired response was found in the review of the literature. Two of the patients agreed to participate in the test. In both patients, we found a seemingly normal analgesic response but a lack of respiratory depression and almost no depression of consciousness, even at doses well above the recommended level for clinical use. The genotyping did not explain the results of the test. CONCLUSIONS: The potential causes of this effect are discussed. We advise clinicians to be aware of this unusual response to remifentanil. If such a response is suspected, we recommend the use of another opioid. If this is suspected before GA, we propose the use of our test as a diagnostic tool.


Assuntos
Anestésicos Combinados/administração & dosagem , Anestésicos Intravenosos/administração & dosagem , Piperidinas/administração & dosagem , Propofol/administração & dosagem , Adulto , Anestésicos Combinados/sangue , Anestésicos Combinados/farmacologia , Anestésicos Intravenosos/sangue , Anestésicos Intravenosos/farmacologia , Conscientização/efeitos dos fármacos , Esquema de Medicação , Resistência a Medicamentos , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Piperidinas/sangue , Piperidinas/farmacologia , Propofol/sangue , Propofol/farmacologia , Remifentanil , Respiração/efeitos dos fármacos
16.
J Chem Phys ; 139(13): 134503, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-24116571

RESUMO

The relatively small dielectric Debye-like process of the monohydroxy alcohol 4-methyl-3-heptanol (4M3H) was found to depend slightly on the intramolecular conformation. Proton and deuteron nuclear magnetic resonance demonstrate that the hydroxyl dynamics and the overall molecular dynamics take place on similar time scales in contrast to the situation for the structural isomer 2-ethyl-1-hexanol (2E1H) [S. Schildmann et al., J. Chem. Phys. 135, 174511 (2011)]. This indicates a very weak decoupling of Debye-like and structural relaxation which was further probed using volume expansivity experiments. Shear viscosity as well as diffusometry measurements were performed and the data were analyzed in terms of the Debye-Stokes-Einstein equations. In mixtures of 4M3H with 2E1H the Debye-like process becomes much stronger and for 2E1H mole fraction of more than 25% the behavior of this alcohol is rapidly approached. This finding is interpreted to indicate that the ring-like supramolecular structures in 4M3H become energetically unfavorable when adding 2E1H, an alcohol that tends to form chain-like molecular aggregates. The concentration dependence of the Kirkwood factor in these mixtures displays a high degree of similarity with experimental results on monohydroxy alcohols in which the pressure or the location of the OH group within the molecular structure is varied.

17.
Acta Anaesthesiol Scand ; 57(6): 793-801, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23495747

RESUMO

BACKGROUND: Mitochondrial dysfunction is an important factor contributing to tissue damage in both severe traumatic brain injury and ischemic stroke. This experimental study explores the possibility to diagnose the condition bedside by utilising intracerebral microdialysis and analysis of chemical variables related to energy metabolism. METHODS: Mitochondrial dysfunction was induced in piglets and evaluated by monitoring brain tissue oxygen tension (PbtO2 ) and cerebral levels of glucose, lactate, pyruvate, glutamate, and glycerol bilaterally. The biochemical variables were obtained by microdialysis and immediate enzymatic analysis. Mitochondrial function was blocked by unilateral infusion of NaCN/KCN (0.5 mol/L) through the microdialysis catheter (N = 5). As a reference, NaCl (0.5 mol/L) was infused by intracerebral microdialysis in one group of animals (N = 3). RESULTS: PbtO2 increased during cyanide infusion and returned to baseline afterwards. The lactate/pyruvate (LP) ratio increased significantly following cyanide infusion because of a marked increase in lactate level while pyruvate remained within normal limits. Glutamate and glycerol increased after cyanide infusion indicating insufficient energy metabolism and degradation of cellular membranes, respectively. CONCLUSION: Mitochondrial dysfunction is characterised by an increased LP ratio signifying a shift in cytoplasmatic redox state at normal or elevated PbtO2 . The condition is biochemically characterised by a marked increase in cerebral lactate with a normal or elevated pyruvate level. The metabolic pattern is different from cerebral ischemia, which is characterised by simultaneous decreases in intracerebral pyruvate and PbtO2 . The study supports the hypothesis that cerebral ischemia and mitochondrial dysfunction may be identified and separated at the bedside by utilising intracerebral microdialysis.


Assuntos
Encéfalo/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Cianeto de Potássio/toxicidade , Cianeto de Sódio/toxicidade , Animais , Pressão Sanguínea/efeitos dos fármacos , Encéfalo/metabolismo , Química Encefálica , Dióxido de Carbono/sangue , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Feminino , Glucose/análise , Ácido Glutâmico/análise , Glicólise/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Pressão Intracraniana/efeitos dos fármacos , Lactatos/análise , Microdiálise , Oximetria , Oxigênio/sangue , Piruvatos/análise , Sus scrofa , Suínos
18.
Acta Anaesthesiol Scand ; 57(2): 229-35, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23017022

RESUMO

BACKGROUND: In patients with traumatic brain injury as well as stroke, impaired cerebral oxidative energy metabolism may be an important factor contributing to the ultimate degree of tissue damage. We hypothesize that mitochondrial dysfunction can be diagnosed bedside by comparing the simultaneous changes in brain tissue oxygen tension (PbtO(2)) and cerebral cytoplasmatic redox state. The study describes cerebral energy metabolism during mitochondrial dysfunction induced by sevoflurane in piglets. METHODS: Ten piglets were included, seven in the experimental group (anesthetized with sevoflurane) and three in the control group (anesthetized with midazolam). PbtO(2) and cerebral levels of glucose, lactate, and pyruvate were monitored bilaterally. The biochemical variables were obtained by intracerebral microdialysis. RESULTS: All global variables were within normal range and did not differ significantly between the groups except for blood lactate that was slightly higher in the experimental group. Mitochondrial dysfunction was observed in the group of animals initially anesthetized with sevoflurane. Cerebral glucose was significantly lower in the experimental group than in the control group whereas lactate and lactate/pyruvate ratio were significantly higher. Pyruvate and tissue oxygen tension remained within normal range in both groups. Changes of intracerebral variables indicating mitochondrial dysfunction were present already from the very start of the monitoring period. CONCLUSION: Intracerebral microdialysis revealed mitochondrial dysfunction by marked increases in cerebral lactate and lactate/pyruvate ratio simultaneously with normal levels of pyruvate and a normal PbtO(2). This metabolic pattern is distinctively different from cerebral ischemia, which is characterized by simultaneous decreases in PbtO(2) and intracerebral pyruvate.


Assuntos
Química Encefálica/fisiologia , Metabolismo Energético/fisiologia , Doenças Mitocondriais/metabolismo , Anestesia por Inalação , Anestésicos Inalatórios , Animais , Gasometria , Pressão Sanguínea/fisiologia , Temperatura Corporal , Citoplasma/metabolismo , Feminino , Glucose/metabolismo , Pressão Intracraniana/fisiologia , Ácido Láctico/metabolismo , Éteres Metílicos , Oxirredução , Consumo de Oxigênio , Ácido Pirúvico/metabolismo , Sevoflurano , Suínos
19.
Genes Immun ; 13(2): 146-54, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21938015

RESUMO

Identification of biomarkers contributing to disease diagnosis, classification or prognosis could be of considerable utility. For example, primary methods to diagnose multiple sclerosis (MS) include magnetic resonance imaging and detection of immunological abnormalities in cerebrospinal fluid. We determined whether gene-expression differences in blood discriminated MS subjects from comparator groups, and identified panels of ratios that performed with varying degrees of accuracy depending upon complexity of comparator groups. High levels of overall accuracy were achieved by comparing MS with homogeneous comparator groups. Overall accuracy was compromised when MS was compared with a heterogeneous comparator group. Results, validated in independent cohorts, indicate that gene-expression differences in blood accurately exclude or include a diagnosis of MS and suggest that these approaches may provide clinically useful prediction of MS.


Assuntos
Expressão Gênica , Esclerose Múltipla/genética , Biomarcadores/análise , Perfilação da Expressão Gênica , Humanos , Esclerose Múltipla/diagnóstico
20.
Br J Cancer ; 106(5): 1016-20, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22315054

RESUMO

BACKGROUND: To report the number of malignant pleural and peritoneal mesotheliomas that have occurred in former Wittenoom crocidolite workers to the end of 2008, to compare this with earlier predictions, and to relate the mesothelioma rate to amount of exposure. METHODS: A group of 6489 men and 419 women who had worked for the company operating the former Wittenoom crocidolite mine and mill at some time between 1943 and 1966 have been followed up throughout Australia and Italy to the end of 2008. RESULTS: The cumulative number of mesotheliomas up to 2008 was 316 in men (268 pleural, 48 peritoneal) and 13 (all pleural) in women. There had been 302 deaths with mesothelioma in men and 13 in women, which was almost 10% of all known deaths. Mesothelioma rate, both pleural and peritoneal, increased with time since first exposure and appeared to reach a plateau after about 40 to 50 years. The mesothelioma rate increased with amount of exposure and the peritoneal mesotheliomas occurred preferentially in the highest exposure group, 37% compared with 15% overall. CONCLUSION: By the end of 2008, the number of mesothelioma deaths had reached 4.7% for all the male workers and 3.1% for the females. Over the past 8 years the numbers were higher than expected. It is predicted that about another 60 to 70 deaths with mesothelioma may occur in men by 2020.


Assuntos
Asbesto Crocidolita/toxicidade , Mesotelioma/epidemiologia , Mineração , Exposição Ocupacional , Neoplasias Peritoneais/epidemiologia , Neoplasias Pleurais/epidemiologia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/mortalidade , Masculino , Mesotelioma/diagnóstico , Mesotelioma/mortalidade , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/mortalidade , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/mortalidade , Austrália Ocidental/epidemiologia
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