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1.
Clin Exp Immunol ; 193(3): 346-360, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29745420

RESUMO

In inflammatory bowel disease (IBD), inflammation is sustained by an exaggerated response of lymphocytes. This results from enhanced expression of anti-apoptotic B cell lymphoma (BCL-2) and BCL-XL associated with a diminished turnover. Azathioprine (AZA) directly targets BCL-2 family-mediated apoptosis. We investigated whether the BCL-2 family expression pattern could be used to predict treatment response to AZA and determined whether BCL-2 inhibitor A-1211212 effectively diminishes lymphocytes and ameliorates inflammation in a model of colitis. BCL-2 family expression pattern was determined by next-generation sequencing (NGS). BCL-2 inhibitor was administered orally to Il10-/- mice. Haematological analyses were performed with an ADVIA 2120 and changes in immune cells were investigated using quantitative polymerase chain reaction (qPCR) and fluorescence activated cell sorter (FACS). We determined similar expression levels of BCL-2 family members in patients with remission and patients refractory to treatment, showing that BCL-2 family expression can not predict AZA treatment response. Expression was not correlated with the modified Truelove and Witts activity index (MTWAI). BCL-2 inhibitor initiated cell death in T cells from patients refractory to AZA and reduced lymphocyte count in Il10-/- mice. FACS revealed diminished CD8+ T cells upon BCL-2 inhibitor in Il10-/- mice without influencing platelets. Tnf, Il1ß, IfnƔ and Mcp-1 were decreased upon BCL-2 inhibitor. A-1211212 positively altered the colonic mucosa and ameliorated inflammation in mice. Pro-apoptotic BCL-2 inhibitor A-1211212 diminishes lymphocytes and ameliorates colitis in Il10-/- mice without inducing thrombocytopenia. BCL-2 inhibition could be a new therapy option for patients refractory to AZA.


Assuntos
Azatioprina/uso terapêutico , Colite/tratamento farmacológico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Linfócitos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Animais , Apoptose , Células Cultivadas , Colite/diagnóstico , Colite/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/genética , Interleucina-10/genética , Linfócitos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Resultado do Tratamento
2.
Diabet Med ; 35(10): 1337-1344, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29797352

RESUMO

AIMS: To investigate depolarization and repolarization durations in people with Type 1 diabetes, including the relationship to age. METHODS: 855 persons with Type 1 diabetes without known heart disease were included and matched with 1710 participants from a general population study. Clinical examinations, questionnaires and biochemistry were assessed. A 10-second 12-lead ECG was performed and analysed digitally. RESULTS: QTc was longer in people with Type 1 diabetes compared to controls (414±16 vs. 411±19 ms, P <0.001), and particularly so in young people with Type 1 diabetes. The fully adjusted increase was 13.8 ms (95% confidence interval (CI): 8.6-19.0 ms, P <0.001) at age 20 years and 3.4 ms (CI: 1.5-5.3 ms, P<0.001) at age 40 years. The rate-corrected QRSc was increased in people with Type 1 diabetes (97±11 vs. 95±11 ms, P <0.001) and was age-independent (P =0.5). JTc was increased in the young people with Type 1 diabetes (10.7 ms (CI: 5.4-16.0 ms, P <0.001) at age 20 years), but not in older people with Type 1 diabetes (interaction age-diabetes, P <0.01). CONCLUSIONS: For people with Type 1 diabetes, cardiac depolarization is increased at all ages, whereas repolarization is increased only relatively in young people with Type 1 diabetes. Hence, young people with Type 1 diabetes may be more prone to ventricular arrhythmias. The findings contribute to the understanding of sudden cardiac death in young people with Type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Coração/fisiopatologia , Volume Sistólico/fisiologia , Adulto , Fatores Etários , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/fisiopatologia , Doenças Assintomáticas , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/fisiopatologia , Eletrocardiografia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
J Intern Med ; 278(2): 211-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25639959

RESUMO

BACKGROUND: Familial Alzheimer's disease (FAD) resulting from gene mutations in PSEN1, PSEN2 and APP is associated with changes in the brain. OBJECTIVE: The aim of this study was to investigate changes in grey matter (GM), white matter (WM) and the cerebrospinal fluid (CSF) in FAD. SUBJECTS: Ten mutation carriers (MCs) with three different mutations in PSEN1 and APP and 20 noncarriers (NCs) were included in the study. Three MCs were symptomatic and seven were presymptomatic (pre-MCs). METHODS: Whole-brain GM volume as well as fractional anisotropy (FA) and mean diffusivity (MD) using voxel-based morphometry and tract-based spatial statistics analyses, respectively, were compared between MCs and NCs. FA and MD maps were obtained from diffusion tensor imaging. RESULTS: A significant increase in MD was found in the left inferior longitudinal fasciculus, cingulum and bilateral superior longitudinal fasciculus in pre-MCs compared with NCs. After inclusion of the three symptomatic MCs in the analysis, the regions became wider. The mean MD of these regions showed significant negative correlation with the CSF level of Aß42, and positive correlations with P-tau181p and T-tau. No differences were observed in GM volume and FA between the groups. CONCLUSIONS: The results of this study suggest that FAD gene mutations affect WM diffusivity before changes in GM volume can be detected. The WM changes observed were related to changes in the CSF, with similar patterns previously observed in sporadic Alzheimer's disease.


Assuntos
Doença de Alzheimer/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Substância Branca/patologia , Adulto , Doença de Alzheimer/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
4.
Clin Exp Immunol ; 181(2): 343-56, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25845418

RESUMO

Exaggerated activation of lymphocytes contributes to the pathogenesis of inflammatory bowel disease (IBD). Medical therapies are linked to the BCL-2 family-mediated apoptosis. Imbalance in BCL-2 family proteins may cause failure in therapeutic responses. We investigated the role of BCL-2 inhibitor ABT-737 for lymphocyte apoptosis in mice under inflammatory conditions. B.6129P2-interleukin (IL)-10(tm1Cgn) /J (IL-10(-/-) ) weighing 25-30 g with ongoing colitis were used. Fifty mg/kg/day ABT-737 was injected intraperitoneally (i.p.). Haematological analyses were performed with an ADVIA 2120 flow cytometer and mass cytometry with a CyTOF 2. Following i.p. administration, ABT-737 was detected in both spontaneous and acute colitis in peripheral blood (PBL) and colon tissue. Treatment led to lymphopenia. CD4(+) CD44(+) CD62L(+) central memory and CD8(+) , CD44(+) CD62L(-) central memory T cells were decreased in PBL upon ABT-737 compared to vehicle-receiving controls. Increased apoptosis upon ABT-737 was determined in blood lymphocytes, splenocytes and Peyer's patches and was accompanied by a decrease in TNF and IL-1B. ABT-737 positively altered the colonic mucosa and ameliorated inflammation, as shown by colonoscopy, histology and colon length. A decreased BIM/BCL-2 ratio or absence of BIM in both Bim(-) (/) (-) and Il10(-) (/) (-) × Bim(-) (/) (-) impeded the protective effect of ABT-737. The BIM/BCL-2 ratio decreased with age and during the course of treatment. Thus, long-term treatment resulted in adapted TNF levels and macroscopic mucosal damage. ABT-737 was efficacious in diminishing lymphocytes and ameliorating colitis in a BIM-dependent manner. Regulation of inappropriate survival of lymphocytes by ABT-737 may provide a therapeutic strategy in IBD.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Compostos de Bifenilo/farmacologia , Colite/tratamento farmacológico , Proteínas de Membrana/genética , Nitrofenóis/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas/genética , Sulfonamidas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Colite/induzido quimicamente , Colite/genética , Colite/patologia , Sulfato de Dextrana , Feminino , Expressão Gênica , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Injeções Intraperitoneais , Interleucina-10/genética , Interleucina-10/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Selectina L/genética , Selectina L/metabolismo , Linfopenia/induzido quimicamente , Linfopenia/genética , Linfopenia/patologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
5.
J Electrocardiol ; 48(1): 35-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25465868

RESUMO

BACKGROUND: T-wave morphology has been shown to be more sensitive than QT and QTc interval to describe repolarization abnormalities. The electrocardiogram (ECG) performed in athletes may manifest abnormalities, including repolarization alterations. The aim of this study was to investigate the characteristics of T-wave morphology features in athletes. METHODS: Eighty male elite athletes, consisting of 40 Tour de France cyclists (age 27±5years), 40 soccer players (age 26±6years) and 40 healthy men (age 27±5years) were included. RESULTS: Sinus bradycardia, left ventricular (LV) hypertrophy, incomplete right bundle branch block and early repolarization were documented in 25 %, 20%, 13% and 14% of athletes, respectively. ECG criteria for LV hypertrophy in 12-lead ECG were more common in cyclists (35%) than in soccer players (5%), P<0.0001. Cyclists and soccer players had significantly longer RR interval, and repolarization features than the control group. CONCLUSIONS: T-wave morphology of athletes is different from non-athletes, depending of the sport. Decreased potassium current in cardiomyocytes associated with LVH may contribute to these changes.


Assuntos
Desempenho Atlético/fisiologia , Eletrocardiografia/métodos , Frequência Cardíaca/fisiologia , Resistência Física/fisiologia , Esportes/fisiologia , Adaptação Fisiológica/fisiologia , Adulto , Comportamento Competitivo/fisiologia , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Mol Psychiatry ; 18(4): 461-70, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22430674

RESUMO

Recently, several genome-wide association studies (GWASs) have led to the discovery of nine new loci of genetic susceptibility in Alzheimer's disease (AD). However, the landscape of the AD genetic susceptibility is far away to be complete and in addition to single-SNP (single-nucleotide polymorphism) analyses as performed in conventional GWAS, complementary strategies need to be applied to overcome limitations inherent to this type of approaches. We performed a genome-wide haplotype association (GWHA) study in the EADI1 study (n=2025 AD cases and 5328 controls) by applying a sliding-windows approach. After exclusion of loci already known to be involved in AD (APOE, BIN1 and CR1), 91 regions with suggestive haplotype effects were identified. In a second step, we attempted to replicate the best suggestive haplotype associations in the GERAD1 consortium (2820 AD cases and 6356 controls) and observed that 9 of them showed nominal association. In a third step, we tested relevant haplotype associations in a combined analysis of five additional case-control studies (5093 AD cases and 4061 controls). We consistently replicated the association of a haplotype within FRMD4A on Chr.10p13 in all the data set analyzed (OR: 1.68; 95% CI: (1.43-1.96); P=1.1 × 10(-10)). We finally searched for association between SNPs within the FRMD4A locus and Aß plasma concentrations in three independent non-demented populations (n=2579). We reported that polymorphisms were associated with plasma Aß42/Aß40 ratio (best signal, P=5.4 × 10(-7)). In conclusion, combining both GWHA study and a conservative three-stage replication approach, we characterised FRMD4A as a new genetic risk factor of AD.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla , Haplótipos/genética , Doença de Alzheimer/sangue , Peptídeos beta-Amiloides/sangue , Estudos de Casos e Controles , Humanos , Polimorfismo de Nucleotídeo Único/genética
7.
Nat Genet ; 26(3): 336-40, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11062475

RESUMO

Mitochondrial dysfunction is an important contributor to human pathology and it is estimated that mutations of mitochondrial DNA (mtDNA) cause approximately 0.5-1% of all types of diabetes mellitus. We have generated a mouse model for mitochondrial diabetes by tissue-specific disruption of the nuclear gene encoding mitochondrial transcription factor A (Tfam, previously mtTFA; ref. 7) in pancreatic beta-cells. This transcriptional activator is imported to mitochondria, where it is essential for mtDNA expression and maintenance. The Tfam-mutant mice developed diabetes from the age of approximately 5 weeks and displayed severe mtDNA depletion, deficient oxidative phosphorylation and abnormal appearing mitochondria in islets at the ages of 7-9 weeks. We performed physiological studies of beta-cell stimulus-secretion coupling in islets isolated from 7-9-week-old mutant mice and found reduced hyperpolarization of the mitochondrial membrane potential, impaired Ca(2+)-signalling and lowered insulin release in response to glucose stimulation. We observed reduced beta-cell mass in older mutants. Our findings identify two phases in the pathogenesis of mitochondrial diabetes; mutant beta-cells initially display reduced stimulus-secretion coupling, later followed by beta-cell loss. This animal model reproduces the beta-cell pathology of human mitochondrial diabetes and provides genetic evidence for a critical role of the respiratory chain in insulin secretion.


Assuntos
DNA Mitocondrial/análise , Proteínas de Ligação a DNA , Diabetes Mellitus/genética , Modelos Animais de Doenças , Proteínas de Grupo de Alta Mobilidade , Insulina/metabolismo , Ilhotas Pancreáticas/patologia , Proteínas Mitocondriais , Proteínas Nucleares , Transativadores , Fatores de Transcrição/deficiência , Proteínas Virais , Proteínas de Xenopus , Trifosfato de Adenosina/metabolismo , Fatores Etários , Animais , Cálcio/farmacologia , Canais de Cálcio Tipo L/metabolismo , Diabetes Mellitus/patologia , Progressão da Doença , Complexo IV da Cadeia de Transporte de Elétrons/análise , Exocitose , Marcação de Genes , Glucose/farmacologia , Humanos , Secreção de Insulina , Integrases/metabolismo , Transporte de Íons , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , Fosforilação Oxidativa , Canais de Potássio/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Taxa Secretória , Succinato Desidrogenase/análise , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Transcrição Gênica , Transgenes
8.
Nat Genet ; 21(1): 133-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9916807

RESUMO

Mutations of mitochondrial DNA (mtDNA) cause several well-recognized human genetic syndromes with deficient oxidative phosphorylation and may also have a role in ageing and acquired diseases of old age. We report here that hallmarks of mtDNA mutation disorders can be reproduced in the mouse using a conditional mutation strategy to manipulate the expression of the gene encoding mitochondrial transcription factor A (Tfam, previously named mtTFA), which regulates transcription and replication of mtDNA. Using a loxP-flanked Tfam allele (TfamloxP) in combination with a cre-recombinase transgene under control of the muscle creatinine kinase promoter, we have disrupted Tfam in heart and muscle. Mutant animals develop a mosaic cardiac-specific progressive respiratory chain deficiency, dilated cardiomyopathy, atrioventricular heart conduction blocks and die at 2-4 weeks of age. This animal model reproduces biochemical, morphological and physiological features of the dilated cardiomyopathy of Kearns-Sayre syndrome. Furthermore, our findings provide genetic evidence that the respiratory chain is critical for normal heart function.


Assuntos
Cardiomiopatia Dilatada/genética , DNA Mitocondrial , Proteínas de Ligação a DNA , Regulação da Expressão Gênica , Bloqueio Cardíaco/genética , Coração/fisiopatologia , Proteínas de Grupo de Alta Mobilidade , Proteínas Mitocondriais , Proteínas Nucleares , Transativadores , Fatores de Transcrição/biossíntese , Proteínas Virais , Proteínas de Xenopus , Animais , Cardiomiopatia Dilatada/fisiopatologia , Creatina Quinase/genética , Modelos Animais de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Bloqueio Cardíaco/fisiopatologia , Humanos , Integrases/genética , Masculino , Camundongos , Camundongos Transgênicos , Músculo Esquelético , Miocárdio , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fatores de Transcrição/genética
9.
Genes Immun ; 13(8): 632-40, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23052709

RESUMO

The major histocompatibility complex class II transactivator (CIITA) gene (16p13) has been reported to associate with susceptibility to multiple sclerosis, rheumatoid arthritis and myocardial infarction, recently also to celiac disease at genome-wide level. However, attempts to replicate association have been inconclusive. Previously, we have observed linkage to the CIITA region in Scandinavian type 1 diabetes (T1D) families. Here we analyze five Swedish T1D cohorts and a combined control material from previous studies of CIITA. We investigate how the genotype distribution within the CIITA gene varies depending on age, and the association to T1D. Unexpectedly, we find a significant difference in the genotype distribution for markers in CIITA (rs11074932, P=4 × 10(-5) and rs3087456, P=0.05) with respect to age, in the collected control material. This observation is replicated in an independent cohort material of about 2000 individuals (P=0.006, P=0.007). We also detect association to T1D for both markers, rs11074932 (P=0.004) and rs3087456 (P=0.001), after adjusting for age at sampling. The association remains independent of the adjacent T1D risk gene CLEC16A. Our results indicate an age-dependent variation in CIITA allele frequencies, a finding of relevance for the contrasting outcomes of previously published association studies.


Assuntos
Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Transativadores/genética , População Branca , Adolescente , Adulto , Fatores Etários , Alelos , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Frequência do Gene , Humanos , Lactente , Recém-Nascido , Lectinas Tipo C/genética , Desequilíbrio de Ligação , Masculino , Proteínas de Transporte de Monossacarídeos/genética , Suécia
10.
Dement Geriatr Cogn Disord ; 32(2): 135-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21952537

RESUMO

BACKGROUND: The APOE ε4 allele is a risk factor for Alzheimer's disease (AD). APOE ε4 is common in non-demented subjects with cognitive impairment. In both healthy people and people with AD, its prevalence has a north-south gradient across Europe. In the present study, we investigated whether the relation between the APOE ε4 allele and cognitive impairment varied across Northern, Middle and Southern Europe. We also investigated whether a north-south gradient existed in subjects with subjective cognitive impairment (SCI), amnestic mild cognitive impairment (MCI) and non-amnestic MCI. METHODS: Data from 16 centers across Europe were analyzed. RESULTS: A north-south gradient in APOE ε4 prevalence existed in the total sample (62.7% for APOE ε4 carriers in the northern region, 42.1% in the middle region, and 31.5% in the southern region) and in subjects with SCI and amnestic MCI separately. Only in Middle Europe was the APOE ε4 allele significantly associated with poor performance on tests of delayed recall and learning, as well as with the amnestic subtype of MCI. CONCLUSION: The APOE ε4 allele frequencies in subjects with SCI and amnestic MCI have a north-south gradient. The relation between the APOE ε4 allele and cognition is region dependent.


Assuntos
Apolipoproteínas E/genética , Transtornos Cognitivos/genética , Cognição , Demência/genética , Transtornos Cognitivos/epidemiologia , Demência/classificação , Demência/epidemiologia , Europa (Continente)/epidemiologia , Frequência do Gene , Humanos , Valores de Referência , Topografia Médica
11.
Acta Psychiatr Scand ; 121(5): 385-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20085555

RESUMO

OBJECTIVE: Recent research suggests that other surrogate markers than QTc, including QTc dispersion and Tpeak-Tend, may better correlate with cardiac arrhythmia risk. While sertindole significantly prolongs the QTc interval, the effects on other markers of arrhythmia risk, such as QTc dispersion and Tpeak-Tend are unknown. METHOD: Digital 12-lead ECG was recorded at baseline and at steady-state in 37 patients switched to sertindole. ECG was analysed for Fridericia-corrected QT duration (QTcF), QT dispersion and Tpeak-Tend. RESULTS: From a baseline QTcF of 407 +/- 22 ms, mean QTcF prolongation during sertindole treatment was 20 +/- 23 ms, P < 0.01. No effect on QTc dispersion was found (-1 +/- 11 ms; P = 0.41). No increased duration of the Tpeak-Tend interval from baseline was found (+7 +/- 21 ms; P = 0.05). CONCLUSION: These findings might be related to the absence of confirmed Torsade de Pointes (TdP) cases related to sertindole exposure, despite sertindole's QTc prolonging effects.


Assuntos
Antipsicóticos/efeitos adversos , Eletrocardiografia/efeitos dos fármacos , Imidazóis/efeitos adversos , Indóis/efeitos adversos , Síndrome do QT Longo/induzido quimicamente , Esquizofrenia/tratamento farmacológico , Processamento de Sinais Assistido por Computador , Adulto , Antipsicóticos/uso terapêutico , Dinamarca , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Imidazóis/uso terapêutico , Indóis/uso terapêutico , Síndrome do QT Longo/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Retirada de Medicamento Baseada em Segurança , Torsades de Pointes/induzido quimicamente
13.
Med Biol Eng Comput ; 44(7): 543-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16937190

RESUMO

The long QT syndrome (LQTS) is a genetic disorder, typically characterized by a prolonged QT interval in the ECG due to abnormal cardiac repolarization. LQTS may lead to syncopal episodes and sudden cardiac death. Various parameters based on T-wave morphology, as well as the QT interval itself have been shown to be useful discriminators, but no single ECG parameter has been sufficient to solve the diagnostic problem. In this study we present a method for discrimination among persons with a normal genotype and those with mutations in the KCNQ1 (KvLQT1 or LQT1) and KCNH2 (HERG or LQT2) genes on the basis of parameters describing T-wave morphology in terms of duration, asymmetry, flatness and amplitude. Discriminant analyses based on 4 or 5 parameters both resulted in perfect discrimination in a learning set of 36 subjects. In both cases cross-validation of the resulting classifiers showed no misclassifications either.


Assuntos
Síndrome do QT Longo/diagnóstico , Adolescente , Adulto , Análise Discriminante , Canal de Potássio ERG1 , Ecocardiografia/métodos , Canais de Potássio Éter-A-Go-Go/genética , Feminino , Humanos , Canal de Potássio KCNQ1/genética , Síndrome do QT Longo/genética , Síndrome do QT Longo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mutação/genética
14.
Waste Manag ; 26(5): 516-25, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16198554

RESUMO

Many developed countries have targeted landfill methane recovery among greenhouse gas mitigation strategies, since methane is the second most important greenhouse gas after carbon dioxide. Major questions remain with respect to actual methane production rates in field settings and the relative mass of methane that is recovered, emitted, oxidized by methanotrophic bacteria, laterally migrated, or temporarily stored within the landfill volume. This paper presents the results of extensive field campaigns at three landfill sites to elucidate the total methane balance and provide field measurements to quantify these pathways. We assessed the overall methane mass balance in field cells with a variety of designs, cover materials, and gas management strategies. Sites included different cell configurations, including temporary clay cover, final clay cover, geosynthetic clay liners, and geomembrane composite covers, and cells with and without gas collection systems. Methane emission rates ranged from -2.2 to >10,000 mg CH(4) m(-2) d(-1). Total methane oxidation rates ranged from 4% to 50% of the methane flux through the cover at sites with positive emissions. Oxidation of atmospheric methane was occurring in vegetated soils above a geomembrane. The results of these studies were used as the basis for guidelines by the French environment agency (ADEME) for default values for percent recovery: 35% for an operating cell with an active landfill gas (LFG) recovery system, 65% for a temporary covered cell with an active LFG recovery system, 85% for a cell with clay final cover and active LFG recovery, and 90% for a cell with a geomembrane final cover and active LFG recovery.


Assuntos
Poluentes Atmosféricos/análise , Metano/análise , Eliminação de Resíduos , Poluentes Atmosféricos/metabolismo , Poluição do Ar/prevenção & controle , Monitoramento Ambiental , França , Metano/metabolismo , Methylococcaceae/metabolismo , Oxirredução
15.
Neuroscience ; 135(1): 273-83, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16084651

RESUMO

Light is the major synchronizer of the mammalian circadian pacemaker located in the suprachiasmatic nucleus. Photic information is perceived by the retina and conveyed to the suprachiasmatic nucleus either directly by the retinohypothalamic tract or indirectly by the intergeniculate leaflet and the geniculohypothalamic tract. In addition, serotonin has been shown to affect the suprachiasmatic nucleus by both direct and indirect serotonin projections from the raphe nuclei. Indeed, systemic as well as local administrations of the serotonin agonist quipazine in the region of the suprachiasmatic nucleus mimic the effects of light on the circadian system of rats, i.e. they induce phase-advances of the locomotor activity rhythm as well as c-FOS expression in the suprachiasmatic nucleus during late subjective night. The aim of this study was to localize the site(s) of action mediating those effects. Phase shifts of the locomotor activity rhythm as well as c-FOS expression in the suprachiasmatic nucleus after s.c. injection of quipazine (10 mg/kg) were assessed in Lewis rats, which had received either radio-frequency lesions of the intergeniculate leaflet or infusions of the serotonin neurotoxin 5,7-dihydroxytryptamine into the suprachiasmatic nucleus (25 microg) or bilateral enucleation. Lesions of intergeniculate leaflet and serotonin afferents to the suprachiasmatic nucleus did not reduce the photic-like effects of quipazine, whereas bilateral enucleation and the subsequent degeneration of the retinohypothalamic tract abolished both the phase-shifting and the FOS-inducing effects of quipazine. The results indicate that photic-like effects of quipazine are mediated via the retinohypothalamic tract.


Assuntos
Hipotálamo/fisiologia , Vias Neurais/fisiologia , Quipazina/farmacologia , Retina/fisiologia , Agonistas do Receptor de Serotonina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Enucleação Ocular , Lateralidade Funcional/fisiologia , Imuno-Histoquímica , Masculino , Atividade Motora/fisiologia , Estimulação Luminosa , Proteínas Proto-Oncogênicas c-fos/biossíntese , Ratos , Ratos Endogâmicos Lew , Serotonina/fisiologia , Núcleo Supraquiasmático/fisiologia
16.
J Neurosci Methods ; 19(2): 95-104, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3821168

RESUMO

A silicone rubber ring maintains an electrode on the electric organ of a mormyrid fish. The electrode is connected with a novel swivel, which allows free motion of the wire around its axis. The principle of the rotating contact is based on magnetic contact between a steel pin (moving) and a steel ball (fixed). Using this apparatus, a single fish within a group is recorded. The general electric activity of the group is recorded by means of two sets of fixed differential electrodes. These devices may be adapted for neuroethological studies of other small animals.


Assuntos
Peixe Elétrico/fisiologia , Eletrodos , Eletrofisiologia/métodos , Animais , Instalação Elétrica , Eletrofisiologia/instrumentação
17.
Eur J Pharmacol ; 284(3): 321-5, 1995 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-8666015

RESUMO

While the effects of excitatory amino acids have been well characterized in the central nervous system, relatively little is known about their possible modulation of elements responsible for hyperalgesia within peripheral tissue. The presented experiments demonstrate that the intraplantar (i.pl.) injection of L-glutamate (30 nmol) evokes a thermal hyperalgesic response in the paw withdrawal latencies of normal rats which is stereospecific. In addition, the i.pl. injection of either the non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 (10 nmol) or the competitive alpha-amino-3-hydroxy-4-methyl-5-isoxazolepropionic acid (AMPA)/kainate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX)(100 nmol) into hindpaws inflamed with carrageenan significantly reduced the thermal hyperalgesic response in rats. Collectively, these results suggest that excitatory amino acids activate a peripheral target which facilitates a hyperalgesic behavioural response to thermal stimulation via a receptor mediated process.


Assuntos
Ácido Glutâmico/farmacologia , Hiperalgesia , 6-Ciano-7-nitroquinoxalina-2,3-diona/farmacologia , Animais , Temperatura Corporal/efeitos dos fármacos , Maleato de Dizocilpina/farmacologia , Temperatura Alta , Masculino , Ratos , Ratos Sprague-Dawley
18.
Health Serv Res ; 34(1 Pt 2): 391-404, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10199683

RESUMO

OBJECTIVE: To demonstrate the feasibility of directly surveying adolescents about the content of preventive health services they have received and to assess the validity of adolescent self-reported recall. DATA SOURCES/SETTING: Audiotaped encounters, telephone interviews, and chart reviews with 14-21 year olds being seen for preventive care visits at 15 pediatric and family medicine private practices, teaching hospital clinics, and health centers. DESIGN: 537 adolescents presenting for well visits were approached, 400 (75 percent) consented, 374 (94 percent) were audiotaped, and 354 (89 percent) completed telephone interviews either two to four weeks or five to seven months after their visits. Audiotapes were coded for screening and counseling across 34 preventive service content areas. Intraobserver reliability (Cohen's kappa) ranged from 0.45 for talking about peers to 0.94 for discussing tobacco. The sensitivity and specificity of the adolescent self-reports were assessed using the audiotape coding as the gold standard. RESULTS: Almost all adolescents surveyed (94 percent) remembered having had a preventive care visit, 93 percent identified the site of care, and most (84 percent) identified the clinician they had seen. There was wide variation in the prevalence of screening, based on the tape coding. Adolescent self-report was moderately or highly sensitive and specific at two weeks and six months for 24 of 34 screening and counseling items, including having discussed: weight, diet, body image, exercise, seatbelts, bike helmet use, cigarettes/smoking, smokeless tobacco, alcohol, drugs, steroids, sex, sexual orientation, birth control, condoms, HIV, STDs, school, family, future plans, emotions, suicidality, and abuse. Self-report was least accurate for blood pressure/cholesterol screening, immunizations, or for having discussed fighting, violence, weapon carrying, sleep, dental care, friends, or over-the-counter drug use. CONCLUSION: Adolescents' self-report of the care they have received is a valid method of determining the content of preventive health service delivery. Although recall of screening and counseling is more accurate within two to four weeks after preventive care visits, adolescents can report accurately on the care they had received five to seven months after the preventive health care visits occurred.


Assuntos
Serviços de Saúde do Adolescente/normas , Satisfação do Paciente/estatística & dados numéricos , Serviços Preventivos de Saúde/normas , Indicadores de Qualidade em Assistência à Saúde/normas , Adolescente , Serviços de Saúde do Adolescente/estatística & dados numéricos , Adulto , Serviços de Saúde Comunitária/normas , Serviços de Saúde Comunitária/estatística & dados numéricos , Feminino , Pesquisas sobre Atenção à Saúde/métodos , Humanos , Masculino , New York , Visita a Consultório Médico/estatística & dados numéricos , Serviços Preventivos de Saúde/estatística & dados numéricos , Indicadores de Qualidade em Assistência à Saúde/estatística & dados numéricos , Distribuição Aleatória , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Gravação de Videoteipe
19.
Waste Manag ; 23(7): 599-607, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12957155

RESUMO

Accurate methods quantifying whole landfill surface flux of methane are important for regulatory and research purposes. This paper presents the results from the analysis of chamber measurements utilizing geospatial techniques [kriging and inverse distance weighting (IDW)] to arrive at an estimation of the whole landfill surface flux from the spatially distributed chamber measurement points. The difficulties in utilizing these methods will be discussed. Methane flux was determined on approximately 20 m grid spacing and variogram analysis was performed in order to model spatial structure, which was used to estimate methane flux at unsampled locations through kriging. Our analysis indicates that while the semi-variogram model showed some spatial structure, IDW was a more accurate interpolation method for this particular site. This was seen in the comparison of the resulting contour maps. IDW, coupled with surface area algorithms to extract the total area of user defined contour intervals, provides a superior estimate of the methane flux as confirmed through the methane balance. It is critical that the results of the emissions estimates be viewed in light of the whole cell methane balance; otherwise, there is no rational check and balance system to validate the results.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Metano/análise , Modelos Teóricos , Eliminação de Resíduos , Algoritmos , Monitoramento Ambiental/normas , Reprodutibilidade dos Testes
20.
J Prof Nurs ; 15(6): 364-71, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10641482

RESUMO

An ethnographic study was conducted to investigate implementation of the clinical nurse III or team leader (TL) role as part of a newly executed nursing differentiated practice model. The six TLs studied were employed in the operating room (OR). Through participant observation, interviews, and document analysis, the TL role--as well as perceptions of the role by the TLs and OR staff--were studied. Problems related to performance of the role and its evolutionary process were delineated. Data analysis involved identifying categories and subcategories of data and developing a coding system to identify themes. Salient themes were related to the culture of the OR. Because of the OR's highly technical environment, the TLs defined their roles in relation to the organizational and technical needs of their surgical service. Refinement of surgeon "preference cards" and "instrument count sheets" was considered the initial priority for the TLs. Various controllable and uncontrollable factors were identified that affected implementation of the new TL role. Findings suggest that introduction of the role requires insight into setting and an emphasis on staging and orientation of employees to the new role.


Assuntos
Enfermagem de Centro Cirúrgico/organização & administração , Antropologia Cultural , Hospitais Universitários/organização & administração , Humanos , Kansas , Enfermeiros Clínicos/organização & administração , Enfermeiros Clínicos/psicologia , Recursos Humanos de Enfermagem Hospitalar/organização & administração , Recursos Humanos de Enfermagem Hospitalar/psicologia , Equipe de Enfermagem/organização & administração , Salas Cirúrgicas/organização & administração , Papel (figurativo) , Recursos Humanos
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