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1.
Mol Breed ; 42(6): 35, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37312967

RESUMO

Chocolate spot (CS), caused by Botrytis fabae Sard., is an important threat to global faba bean production. Growing resistant faba bean cultivars is, therefore, paramount to preventing yield loss. To date, there have been no reported quantitative trait loci (QTL) associated with CS resistance in faba bean. The objective of this study was to identify genomic regions associated with CS resistance using a recombinant inbred line (RIL) population derived from resistant accession ILB 938. A total of 165 RILs from the cross Mélodie/2 × ILB 938/2 were genotyped and evaluated for CS reactions under replicated controlled climate conditions. The RIL population showed significant variation in response to CS resistance. QTL analysis identified five loci contributing to CS resistance on faba bean chromosomes 1 and 6, accounting for 28.4% and 12.5%, respectively, of the total phenotypic variance. The results of this study not only provide insight into disease-resistance QTL, but also can be used as potential targets for marker-assisted breeding in faba bean genetic improvement for CS resistance. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-022-01307-7.

2.
J Exp Biol ; 224(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33914032

RESUMO

Animals must selectively attend to relevant stimuli and avoid being distracted by unimportant stimuli. Jumping spiders (Salticidae) do this by coordinating eyes with different capabilities. Objects are examined by a pair of high-acuity principal eyes, whose narrow field of view is compensated for by retinal movements. The principal eyes overlap in field of view with motion-sensitive anterior-lateral eyes (ALEs), which direct their gaze to new stimuli. Using a salticid-specific eyetracker, we monitored the gaze direction of the principal eyes as they examined a primary stimulus. We then presented a distractor stimulus visible only to the ALEs and observed whether the principal eyes reflexively shifted their gaze to it or whether this response was flexible. Whether spiders redirected their gaze to the distractor depended on properties of both the primary and distractor stimuli. This flexibility suggests that higher-order processing occurs in the management of the attention of the principal eyes.


Assuntos
Percepção de Movimento , Aranhas , Animais , Atenção , Movimento , Retina
3.
PLoS One ; 15(9): e0238579, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32898170

RESUMO

BACKGROUND: The insertion of filiform needles intramuscularly (a.k.a. intramuscular stimulation/dry needling) has been suggested as a possible treatment for various painful musculoskeletal conditions. Our aim was to answer the question, is intramuscular stimulation more effective than sham intramuscular stimulation/dry needling for the treatment of Achilles tendinopathy? METHODS: 52 participants with persistent midportion Achilles tendinopathy began and 46 completed one of three treatment protocols which were randomly assigned: (G3) a 12-week rehabilitation program of progressive tendon loading plus intramuscular stimulation (n = 25), (G2) the same rehabilitation program but with sham intramuscular stimulation (n = 19), or (G1) a reference group of rehabilitation program alone (as an additional control) (n = 8). The a priori primary outcome measure was change in VISA-A score at 12 weeks-VISA-A was also measured at 6 weeks, and at 6 and 12 months. Secondary outcome measures include the proportion of patients who rated themselves as much or very much improved (%), dorsiflexion range of motion (degrees), and tendon thickness (mm). RESULTS: The study retention was 94% at 12 weeks and 88% at 1 year. VISA-A score improved in all three groups over time (p<0.0001), with no significant difference among the three groups in VISA-A score at the start of the study (mean ± SD: G3 59 ± 13, G2 57 ± 17, G1 56 ± 22), at 12 weeks (G3 76 ± 14, G2 76 ± 15, G1 82 ± 11) or at any other timepoint. The percentage of patients who rated themselves as much or very much improved (i.e. treatment success) was not different after 12 weeks (G3 70%, G2 89%, G1 86% p = 0.94), or at 26 (p = 0.62) or 52 weeks (p = 0.71). No clinically significant effects of intervention group were observed in any of the secondary outcome measures. CONCLUSION: The addition of intramuscular stimulation to standard rehabilitation for Achilles tendinopathy did not result in any improvement over the expected clinical benefit achieved with exercise-based rehabilitation alone.


Assuntos
Tendão do Calcâneo/fisiopatologia , Modalidades de Fisioterapia , Tendinopatia/terapia , Adulto , Doença Crônica , Terapia por Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Tendinopatia/fisiopatologia , Tendinopatia/reabilitação , Resultado do Tratamento
4.
J Pediatr ; 193: 155-163.e5, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29198542

RESUMO

OBJECTIVE: To prospectively evaluate the acute impact of Kawasaki disease (KD) on health-related quality of life (HRQoL) and to assess deterioration in the HRQoL experienced by children with KD compared with other childhood diseases. STUDY DESIGN: We merged the Outcomes Assessment Program database obtained prospectively with the existing KD database and queried for KD admissions between 1 month and 13 years of age. HRQoL was evaluated with the parent-proxy Pediatric Quality of Life Inventory (PedsQL) 4.0 Generic Core and Infant Scales. We compared the KD HRQoL results with those obtained from newly diagnosed patients with cancer and pneumonia, matched for age, sex and race. PedsQL total scores over time were assessed with ANCOVA models, adjusted for matching variables and PedsQL score prior to admission. RESULTS: We identified 89 patients with KD and compared 65 subjects with an equal number with pneumonia and with 67 subjects with newly diagnosed cancer. Patients with demonstrated lower PedsQL total score on admission and suffered a significantly greater HRQoL decline from baseline to admission than the other groups. KD diagnostic subtype (complete or incomplete) and coronary artery dilatation were not associated with HRQoL outcomes. However, non-intravenous immunoglobulin responders showed greater HRQoL decline than responders (P = .03). CONCLUSIONS: Children with KD suffer acute and significant HRQoL impairment exceeding that of children newly diagnosed with cancer. Lack of immediate treatment response may exert an additional HRQoL burden, whereas KD subtype and coronary artery dilatation do not.


Assuntos
Efeitos Psicossociais da Doença , Síndrome de Linfonodos Mucocutâneos/psicologia , Qualidade de Vida , Adolescente , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/psicologia , Bases de Dados Factuais , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Masculino , Neoplasias/psicologia , Pais , Pneumonia/psicologia , Estudos Prospectivos , Psicometria/métodos
5.
Nutr Res ; 36(8): 827-34, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27440537

RESUMO

Kawasaki disease (KD) is an acute vasculitis affecting children. Incidence of KD varies according to ethnicity and is highest in Asian populations. Although genetic differences may explain this variation, dietary or environmental factors could also be responsible. The objectives of this study were to determine dietary soy and isoflavone consumption in a cohort of KD children just before disease onset and their mothers' intake during pregnancy and nursing. We tested the hypothesis that soy isoflavone consumption is associated with risk of KD in US children, potentially explaining some of the ethnic-cultural variation in incidence. We evaluated soy food intake and isoflavone consumption in nearly 200 US KD cases and 200 age-matched controls using a food frequency questionnaire for children and in their mothers. We used a logistic regression model to test the association of isoflavones and KD. Maternal surveys on soy intake during pregnancy and nursing showed no significant differences in isoflavone consumption between groups. However, we identified significantly increased KD risk in children for total isoflavone (odds ratio [OR], 2.33; 95% confidence interval [CI], 1.37-3.96) and genistein (OR, 2.46; 95% CI, 1.46-4.16) intakes, when comparing high soy consumers vs nonconsumers. In addition, significantly increased KD risk occurred in Asian-American children with the highest consumption (total isoflavones: OR, 7.29; 95% CI, 1.73-30.75; genistein: OR, 8.33; 95% CI, 1.92-36.24) compared to whites. These findings indicate that childhood dietary isoflavone consumption, but not maternal isoflavone intake during pregnancy and nursing, relates to KD risk in an ethnically diverse US population.


Assuntos
Dieta/efeitos adversos , Glycine max/química , Isoflavonas/administração & dosagem , Isoflavonas/efeitos adversos , Síndrome de Linfonodos Mucocutâneos/etiologia , Asiático , Criança , Pré-Escolar , Registros de Dieta , Inquéritos sobre Dietas , Feminino , Genisteína/administração & dosagem , Genisteína/efeitos adversos , Humanos , Lactente , Masculino , Troca Materno-Fetal , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Gravidez , Fatores de Risco , Alimentos de Soja/efeitos adversos , Inquéritos e Questionários
8.
Eur J Radiol ; 85(1): 279-285, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26507864

RESUMO

OBJECTIVES: To compare 3T T1 mapping to conventional T2-weighted (T2W) imaging for delineating myocardial oedema one week after ST-elevation myocardial infarction (STEMI), and to explore the confounding effects of microvascular obstruction (MVO) on each technique. METHODS: T2W spectral attenuated inversion recovery and native T1 mapping were applied in 10 healthy volunteers and 62 STEMI patients, and late gadolinium enhancement was included for infarct localisation at 1 week and at 6 months post-STEMI. Segmental T1 values and T2W signal intensity ratios were calculated; oedema volumes and salvage indices were determined in patients using image thresholding-a receiver operator characteristic (ROC) derived T1 threshold, and a 2SD T2W threshold; and the results were compared between patients with/without MVO (n=35/27). RESULTS: Native T1 mapping delineated oedema with significantly better discriminatory power than T2W-as indicated by ROC analysis (area-under-the-curve, AUC=0.89 versus 0.83, p=0.009; and sensitivity/specificity=83/83% versus 73/73%). The optimal ROC threshold derived for T1 mapping was 1241ms, which gave significantly larger oedema volumes than 2SD T2W (p=0.006); with this threshold, patients with and without MVO showed similar oedema volumes, but patients with MVO had significantly poorer salvage indices (p<0.05) than those without. Neither method was significantly affected by MVO, the volume of which was seen to increase exponentially with infarct size. CONCLUSIONS: Native T1 mapping at 3T can delineate oedema one week post-STEMI, showing larger oedema volumes and better discriminatory power than T2W imaging, and it is suitable for quantitative thresholding. Both techniques are robust against MVO-related magnetic susceptibility.


Assuntos
Vasos Coronários/patologia , Imageamento por Ressonância Magnética/métodos , Microvasos/patologia , Infarto do Miocárdio/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Curva ROC , Sensibilidade e Especificidade , Fatores de Tempo
9.
PLoS One ; 10(8): e0135262, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26266538

RESUMO

Hypertrophic stimuli cause transcription of the proto-oncogene c-Myc (Myc). Prior work showed that myocardial knockout of c-Myc (Myc) attenuated hypertrophy and decreased expression of metabolic genes after aortic constriction. Accordingly, we assessed the interplay between Myc, substrate oxidation and cardiac function during early pressure overload hypertrophy. Mice with cardiac specific, inducible Myc knockout (MycKO-TAC) and non-transgenic littermates (Cont-TAC) were subjected to transverse aortic constriction (TAC; n = 7/group). Additional groups underwent sham surgery (Cont-Sham and MycKO-Sham, n = 5 per group). After two weeks, function was measured in isolated working hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketone bodies and unlabeled glucose and insulin. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. In sham hearts, Myc knockout did not affect cardiac function or substrate preferences for the citric acid cycle. However, Myc knockout altered fractional contributions during TAC. The unlabeled fractional contribution increased in MycKO-TAC versus Cont-TAC, whereas ketone and free fatty acid fractional contributions decreased. Additionally, protein posttranslational modifications by O-GlcNAc were significantly greater in Cont-TAC versus both Cont-Sham and MycKO-TAC. In conclusion, Myc alters substrate preferences for the citric acid cycle during early pressure overload hypertrophy without negatively affecting cardiac function. Myc also affects protein posttranslational modifications by O-GlcNAc during hypertrophy, which may regulate Myc-induced metabolic changes.


Assuntos
Estenose da Valva Aórtica/metabolismo , Cardiomiopatia Hipertrófica/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-myc/metabolismo , Acetilação , Acetilglucosamina/metabolismo , Animais , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/fisiopatologia , Cardiomiopatia Hipertrófica/etiologia , Cardiomiopatia Hipertrófica/fisiopatologia , Ciclo do Ácido Cítrico , Camundongos , Proteínas Proto-Oncogênicas c-myc/genética
10.
Open Heart ; 2(1): e000206, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25815208

RESUMO

OBJECTIVE: Despite treatment with intravenous immunoglobulin (IVIG), the natural progression to coronary artery stenosis in Kawasaki disease is not well defined and remains a potential cause of long-term morbidity. We present a novel study, at a US tertiary paediatric care centre, identifying risk factors for stenosis. METHODS: We reviewed charts of all children who underwent cardiac catheterisation for coronary artery abnormalities, from 1998 to January 2014, at a tertiary paediatric care centre. Demographic and diagnostic data included time intervals to echocardiographic changes and confirmed catheterisation cases of stenosis. Multivariate survival analysis was used to evaluate risk factors with stenosis formation as the main outcome measure. RESULTS: 53 children met the inclusion criteria and 18 (34.6%) developed stenosis. Only those with giant coronary aneurysms (GCA) developed stenosis, with the highest risk group overall being children under the age of 6 months (hazard ratio (HR) 2.82 3.79, p=0.004). In a subset of only cases of GCA (33), a majority went on to develop stenosis (18/33). Median time to diagnosis was 190 days. In this group, children under the age of 6 months were again at highest risk (HR 2.62, p=0.04). IVIG administration, sex and ethnicity were not statistically significant predictors. CONCLUSIONS: This retrospective study demonstrates a relatively high incidence of stenosis in children with Kawasaki disease and coronary vascular abnormalities. Overall, a majority of cases with GCA progressed into stenosis, with children under the age of 6 months being at highest risk.

12.
Eur Heart J ; 35(19): 1255-62, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24639423

RESUMO

AIM: Despite prompt revascularization of acute myocardial infarction (AMI), substantial myocardial injury may occur, in part a consequence of ischaemia reperfusion injury (IRI). There has been considerable interest in therapies that may reduce IRI. In experimental models of AMI, sodium nitrite substantially reduces IRI. In this double-blind randomized placebo controlled parallel-group trial, we investigated the effects of sodium nitrite administered immediately prior to reperfusion in patients with acute ST-elevation myocardial infarction (STEMI). METHODS AND RESULTS: A total of 229 patients presenting with acute STEMI were randomized to receive either an i.v. infusion of 70 µmol sodium nitrite (n = 118) or matching placebo (n = 111) over 5 min immediately before primary percutaneous intervention (PPCI). Patients underwent cardiac magnetic resonance imaging (CMR) at 6-8 days and at 6 months and serial blood sampling was performed over 72 h for the measurement of plasma creatine kinase (CK) and Troponin I. Myocardial infarct size (extent of late gadolinium enhancement at 6-8 days by CMR-the primary endpoint) did not differ between nitrite and placebo groups after adjustment for area at risk, diabetes status, and centre (effect size -0.7% 95% CI: -2.2%, +0.7%; P = 0.34). There were no significant differences in any of the secondary endpoints, including plasma troponin I and CK area under the curve, left ventricular volumes (LV), and ejection fraction (EF) measured at 6-8 days and at 6 months and final infarct size (FIS) measured at 6 months. CONCLUSIONS: Sodium nitrite administered intravenously immediately prior to reperfusion in patients with acute STEMI does not reduce infarct size.


Assuntos
Cardiotônicos/administração & dosagem , Infarto do Miocárdio/tratamento farmacológico , Nitrito de Sódio/administração & dosagem , Biomarcadores/metabolismo , Método Duplo-Cego , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/patologia , Reperfusão Miocárdica/métodos , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Intervenção Coronária Percutânea/métodos , Resultado do Tratamento
13.
J Transl Med ; 11: 116, 2013 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-23648219

RESUMO

BACKGROUND: Whilst advances in reperfusion therapies have reduced early mortality from acute myocardial infarction, heart failure remains a common complication, and may develop very early or long after the acute event. Reperfusion itself leads to further tissue damage, a process described as ischaemia-reperfusion-injury (IRI), which contributes up to 50% of the final infarct size. In experimental models nitrite administration potently protects against IRI in several organs, including the heart. In the current study we investigate whether intravenous sodium nitrite administration immediately prior to percutaneous coronary intervention (PCI) in patients with acute ST segment elevation myocardial infarction will reduce myocardial infarct size. This is a phase II, randomised, placebo-controlled, double-blinded and multicentre trial. METHODS AND OUTCOMES: The aim of this trial is to determine whether a 5 minute systemic injection of sodium nitrite, administered immediately before opening of the infarct related artery, results in significant reduction of IRI in patients with first acute ST elevation myocardial infarction (MI). The primary clinical end point is the difference in infarct size between sodium nitrite and placebo groups measured using cardiovascular magnetic resonance imaging (CMR) performed at 6-8 days following the AMI and corrected for area at risk (AAR) using the endocardial surface area technique. Secondary end points include (i) plasma creatine kinase and Troponin I measured in blood samples taken pre-injection of the study medication and over the following 72 hours; (ii) infarct size at six months; (iii) Infarct size corrected for AAR measured at 6-8 days using T2 weighted triple inversion recovery (T2-W SPAIR or STIR) CMR imaging; (iv) Left ventricular (LV) ejection fraction measured by CMR at 6-8 days and six months following injection of the study medication; and (v) LV end systolic volume index at 6-8 days and six months. FUNDING, ETHICS AND REGULATORY APPROVALS: This study is funded by a grant from the UK Medical Research Council. This protocol is approved by the Scotland A Research Ethics Committee and has also received clinical trial authorisation from the Medicines and Healthcare products Regulatory Agency (MHRA) (EudraCT number: 2010-023571-26). TRIAL REGISTRATION: ClinicalTrials.gov: NCT01388504 and Current Controlled Trials: ISRCTN57596739.


Assuntos
Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Nitrito de Sódio/uso terapêutico , Adolescente , Adulto , Idoso , Cardiotônicos/farmacologia , Método Duplo-Cego , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/química , Intervenção Coronária Percutânea , Reino Unido , Adulto Jovem
14.
J Appl Physiol (1985) ; 111(2): 473-84, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21596914

RESUMO

In developing countries, the chronic exposure to carbon monoxide (CO) from biomass-fueled cookstoves may pose a significant health risk for women who use these stoves, especially for those with underlying clinical conditions that impair tissue oxygenation, e.g., anemia and coronary artery disease. CO concentrations measured in the vicinity of these cookstoves often exceed World Health Organization (WHO) indoor air guidelines for an 8-h average (9 ppm) and a 1-h maximum (26 ppm). Carboxyhemoglobin levels, reported infrequently because they are difficult to obtain, often exceed the WHO threshold of 2.5%. Despite this evidence, specific adverse effects have not yet been linked with chronic CO exposures in these women. Furthermore, anemia, which is prevalent in populations that use biomass fuels, could exacerbate the adverse effects of chronic CO exposure. Because of the difficulties inherent in conducting prospective studies to address this issue, we used a mathematical model to calculate the effects of reported CO levels and exercise on carboxyhemoglobin for women living in 1) Guatemalan villages at altitudes of 4,429-4,593 ft, and 2) coastal villages in Pakistan. In addition, we used the model to calculate the effects of CO exposures in women with moderate to severe anemia on specific physiological parameters (carboxyhemoglobin, carboxymyoglobin, cardiac output, and tissue Po(2)) at exercise levels representing the activities in which these women would be engaged. Our results demonstrate the efficacy of using a mathematical model to predict the physiologic responses to CO and also demonstrate that chronic anemia is a critically important determinant of CO toxicity in these women.


Assuntos
Anemia/fisiopatologia , Biomassa , Monóxido de Carbono/efeitos adversos , Culinária , Medição de Risco/métodos , Adulto , Monóxido de Carbono/metabolismo , Carboxihemoglobina/análise , Débito Cardíaco/efeitos dos fármacos , Exposição Ambiental , Exercício Físico/fisiologia , Feminino , Guatemala , Hemoglobinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Mioglobina/metabolismo , Consumo de Oxigênio/fisiologia , Paquistão , Adulto Jovem
15.
J Clin Neurophysiol ; 27(4): 274-84, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20634711

RESUMO

Elderly subjects exhibit declining sleep efficiency parameters with longer time spent awake at night and greater sleep fragmentation. In this article, we report on the changes in cortical interdependence during sleep stages between 15 middle-aged (range: 42-50 years) and 15 elderly (range: 71-86 years) women subjects. Cortical interdependence assessed from EEG signals typically exhibits increasing levels of correlation because human subjects progress from wake to deeper stages of sleep. EEG signals acquired from previously existing polysomnogram datasets were subjected to mutual information analysis to detect changes in information transmission associated with change in sleep stage and to understand how age affects the interdependence values. We observed a significant reduction in the interdependence between central EEG signals of elderly subjects in nonrapid eye movement and rapid eye movement stage sleep in comparison with middle-aged subjects (age group effect: elderly versus middle aged P < 0.001, sleep stage effect: P < 0.001, interaction effect between age group and sleep stage: P = 0.007). A narrowband analysis revealed that the reduction in mutual information was present in delta, theta, and sigma frequencies. These findings suggest that the lowered cortical interdependence in sleep of elderly subjects may indicate independently evolving dynamic neural activities at multiple cortical sites. The loss of synchronization between neural activities during sleep in the elderly may make these women more susceptible to localized disturbances that could lead to frequent arousals.


Assuntos
Envelhecimento/fisiologia , Córtex Cerebral/fisiologia , Eletroencefalografia , Processamento de Sinais Assistido por Computador , Fases do Sono , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Nível de Alerta , Feminino , Humanos , Pessoa de Meia-Idade , Polissonografia , Estudos Retrospectivos , Fatores de Tempo
16.
Int J Psychophysiol ; 77(2): 71-82, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20450941

RESUMO

Spontaneous cortical arousals in non-REM sleep increase with age and contribute to sleep fragmentation in the elderly. EEG spectral power in the faster frequencies exhibits well-described shifts during arousals. On the other hand, EEG activities also exhibit correlations, which are interpreted as an index of interdependence between distant cortical neural activities. The possibility of changes to the interdependence between cortical regions due to an arousal has not been considered. In this work, using previously recorded C3A2 and C4A1 EEG signals from two groups of adults, middle-aged (42-50 years) and elderly (71-86 years) women, we examined the effects of spontaneous arousals in NREM sleep on cortical interdependence. We quantified the auto- and cross-correlations in these signals using mutual information and characterized these correlations in periods before the onset and following the end of arousals. The pre-arousal period exhibited significantly higher interdependence between central regions than that following the arousal in both age groups (middle-aged: p=0.004, elderly: p<0.0001). Also, for both EEG signals the auto mutual information had a faster rate of decay, implying lower signal predictability, following the arousal than prior to it (both age groups, p<0.0001). These results indicate that the state of the cortex is different after, compared to before, the arousal even when the spectral power changes characteristic of an arousal are no longer visible. The findings suggest that the state following an arousal characterized by lower interdependence may resemble a more vigilant period during which the system may be vulnerable to more arousals.


Assuntos
Nível de Alerta/fisiologia , Córtex Cerebral/fisiologia , Eletroencefalografia , Fases do Sono/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Eletroencefalografia/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Polissonografia/métodos , Fatores de Tempo
17.
Artigo em Inglês | MEDLINE | ID: mdl-20160207

RESUMO

The authors aim to investigate brain plasticity and vulnerability through the study of the relationship of age at the time of brain injury and neurocognitive and psychiatric outcome. Children with early stroke performed more poorly compared with children with late stroke in a wide variety of domains including intellectual function, language, memory, visuospatial function, academic function, and psychiatric problems. The exception to this pattern was that children with late stroke performed more poorly in two of three executive function tests. These findings suggest that in children with focal brain injury, as in those with more diffuse brain insults, younger age at injury predicts worse neurocognitive outcomes, although this may not apply to selected executive function outcomes. Adverse psychiatric outcome after early stroke is less direct but is evident in terms of severity in affected cases.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Plasticidade Neuronal/fisiologia , Acidente Vascular Cerebral/congênito , Acidente Vascular Cerebral/diagnóstico , Logro , Adolescente , Idade de Início , Criança , Pré-Escolar , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Gravidez , Acidente Vascular Cerebral/epidemiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
18.
Ann Biomed Eng ; 38(2): 403-38, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19834811

RESUMO

Clinically significant myocardial abnormalities (e.g., arrhythmias, S-T elevation) occur in patients with mild-to-severe carbon monoxide (CO) poisoning. We enhanced our previous whole body model [Bruce, E. N., M. C. Bruce, and K. Erupaka. Prediction of the rate of uptake of carbon monoxide from blood by extravascular tissues. Respir. Physiol. Neurobiol. 161(2):142-159, 2008] by adding a cardiac compartment (containing three vascular and two tissue subcompartments differing in capillary density) to predict myocardial carboxymyoglobin (MbCO) and oxygen tensions (P(c)O2) for several CO exposure regimens at rest and during exercise. Model predictions were validated with experimental data in normoxia, hypoxia, and hyperoxia. We simulated exposure at rest to 6462 ppm CO (10 min) and to 265 ppm CO (480 min), and during three levels of exercise at 20% HbCO. We compared responses of carboxyhemoglobin (HbCO), MbCO and P(c)O2 to estimate the potential for myocardial injury due to CO hypoxia. Simulation results predict that during CO exposures and subsequent therapies, cardiac tissue has higher MbCO levels and lower P(c)O2's than skeletal muscle. CO exposure during exercise further decreases P(c)O2 from resting levels. We conclude that in rest and moderate exercise, the myocardium is at greater risk for hypoxic injury than skeletal muscle during the course of CO exposure and washout. Because the model can predict CO uptake and distribution in human myocardium, it could be a tool to estimate the potential for hypoxic myocardial injury and facilitate therapeutic intervention.


Assuntos
Intoxicação por Monóxido de Carbono/complicações , Intoxicação por Monóxido de Carbono/fisiopatologia , Monóxido de Carbono/sangue , Coração/fisiopatologia , Modelos Cardiovasculares , Miocárdio Atordoado/etiologia , Miocárdio Atordoado/fisiopatologia , Animais , Simulação por Computador , Humanos
19.
J Clin Neurophysiol ; 26(4): 257-66, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19590434

RESUMO

The regularity of electroencephalogram signals was compared between middle-aged (47.2 +/- 2.0 years) and elderly (78.4 +/- 3.8 years) female subjects in wake, nonrapid eye movement stages 2 and 3 (S-2, S-3), and rapid eye movement sleep. Signals from C3A2 leads of healthy subjects, acquired from polysomnograms obtained from the Sleep Heart Health Study, were analyzed using both sample entropy (SaEn) and power spectral analysis (delta, theta, alpha, and beta frequency band powers). SaEn changed systematically and significantly (P < 0.001) with sleep state in both age groups, following the relationships wake > rapid eye movement > S-2 > S-3. SaEn was found to be negatively correlated with delta power and positively correlated with beta power. Small changes in SaEn seem to reflect changes in spectral content rather than changes in regularity of the signal. A better predictor of SaEn than the frequency band powers was the logarithm of the power ratio (alpha + beta)/(delta + theta). Thus, SaEn seems to reflect the balance between sleep-promoting and alertness-promoting mechanisms. SaEn of the elderly was larger than that of middle-aged subjects in S-2 (P = 0.029) and rapid eye movement (P = 0.001), suggesting that cortical state is shifted toward alertness in elderly subjects in these sleep states compared with the middle-aged subjects.


Assuntos
Envelhecimento/fisiologia , Eletroencefalografia , Processamento de Sinais Assistido por Computador , Fases do Sono/fisiologia , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Polissonografia
20.
Respir Physiol Neurobiol ; 161(2): 142-59, 2008 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18313993

RESUMO

Uptake of environmental carbon monoxide (CO) via the lungs raises the CO content of blood and of myoglobin (Mb)-containing tissues, but the blood-to-tissue diffusion coefficient for CO (DmCO) and tissue CO content are not easily measurable in humans. We used a multicompartment mathematical model to predict the effects of different values of DmCO on the time courses and magnitudes of CO content of blood and Mb-containing tissues when various published experimental studies were simulated. The model enhances our earlier model by adding mass balance equations for oxygen and by dividing the muscle compartment into two subcompartments. We found that several published experimental findings are compatible with either fast or slow rates of blood-tissue transfer of CO, whereas others are only compatible with slow rates of tissue uptake of CO. We conclude that slow uptake is most consistent with all of the experimental data. Slow uptake of CO by tissue is primarily due to the very small blood-to-tissue partial pressure gradients for CO.


Assuntos
Monóxido de Carbono/metabolismo , Modelos Biológicos , Músculos/metabolismo , Consumo de Oxigênio/fisiologia , Troca Gasosa Pulmonar/fisiologia , Algoritmos , Animais , Sangue/metabolismo , Compartimentos de Líquidos Corporais/fisiologia , Simulação por Computador , Humanos , Distribuição Tecidual
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