Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Brain Cogn ; 177: 106164, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670050

RESUMO

Recent work has found that the presence of transient, oscillatory burst-like events, particularly within the beta band (15-29 Hz), is more closely tied to disease state and behavior across species than traditional electroencephalography (EEG) power metrics. This study sought to examine whether features of beta events over frontoparietal electrodes were associated with early life stress (ELS) and the related clinical presentation. Eighteen adults with documented ELS (n = 18; ELS + ) and eighteen adults without documented ELS (n = 18; ELS-) completed eyes-closed resting state EEG as part of their participation in a larger childhood stress study. The rate, power, duration, and frequency span of transient oscillatory events were calculated within the beta band at five frontoparietal electrodes. ELS variables were positively associated with beta event rate at Fp2 and beta event duration at Pz, in that greater ELS was associated with higher resting rates and longer durations. These beta event characteristics were used to successfully distinguish between ELS + and ELS- groups. In an independent clinical dataset (n = 25), beta event power at Pz was positively correlated with ELS. Beta events deserve ongoing investigation as a potential disease marker of ELS and subsequent psychiatric treatment outcomes.


Assuntos
Ritmo beta , Eletroencefalografia , Estresse Psicológico , Humanos , Feminino , Adulto , Masculino , Ritmo beta/fisiologia , Estresse Psicológico/fisiopatologia , Eletroencefalografia/métodos , Lobo Frontal/fisiopatologia , Lobo Parietal/fisiopatologia , Adulto Jovem , Pessoa de Meia-Idade
2.
Front Physiol ; 14: 1279314, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38033330

RESUMO

Introduction: Body temperature is essential for diagnosing, managing, and following multiple medical conditions. There are several methods and devices to measure body temperature, but most do not allow continuous and prolonged measurement of body temperature. Noninvasive skin temperature sensor combined with a heat flux sensor, also known as the "double sensor" technique, is becoming a valuable and simple method for frequently monitoring body temperature. Methods: Body temperature measurements using the "double sensor" method in a wearable monitoring device were compared with oral and core body temperature measurements using medical grade thermometers, analyzing data from two prospective clinical trials of different clinical scenarios. One study included 45 hospitalized COVID-19 patients in which oral measurements were taken using a hand-held device, and the second included 18 post-cardiac surgery patients in which rectal measurements were taken using a rectal probe. Results: In study 1, Bland-Altman analysis showed a bias of -0.04°C [0.34-(-0.43)°C, 95% LOA] with a correlation of 99.4% (p < 0.001). In study 2, Bland-Altman analysis showed a bias of 0.0°C [0.27-(-0.28)°C, 95% LOA], and the correlation was 99.3% (p < 0.001). In both studies, stratifying patients based on BMI and skin tone showed high accordance in all sub-groups. Discussion: The wearable monitor showed high correlation with oral and core body temperature measurements in different clinical scenarios.

3.
Chron Respir Dis ; 20: 14799731231198865, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37612250

RESUMO

BACKGROUND: Respiratory rate (RR) is used for the diagnosis and management of medical conditions and can predict clinical changes. Heavy workload, understaffing, and errors related to poor recording make it underutilized. Wearable devices may facilitate its use. METHODS: RR measurements using a wearable photoplethysmography-based monitor were compared with medical grade devices in complementary clinical scenarios: Study one included a comparison to a capnograph in 35 healthy volunteers; Study two included a comparison to a ventilator monitor in 18 ventilated patients; and Study three included a comparison to capnograph in 92 COVID-19 patients with active pulmonary disease. Pearson's correlations and Bland-Altman analysis were used to assess the accuracy and agreement between the measurement techniques, including stratification for Body Mass Index (BMI) and skin tone. Statistical significance was set at p ≤ 0.05. RESULTS: High correlation was found in all studies (r = 0.991, 0.884, and 0.888, respectively, p < 0.001 for all). 95% LOA of ±2.3, 1.7-(-1.6), and ±3.9 with a bias of < 0.1 breaths per minute was found in Bland-Altman analysis in studies 1,2, and 3, respectively. In all, high accordance was found in all sub-groups. CONCLUSIONS: RR measurements using the wearable monitor were highly-correlated with medical-grade devices in various clinical settings. TRIAL REGISTRATION: ClinicalTrials.gov, https://clinicaltrials.gov/ct2/show/NCT03603860.


Assuntos
Taxa Respiratória , Dispositivos Eletrônicos Vestíveis , Humanos , Índice de Massa Corporal , Monitorização Fisiológica/métodos
4.
Neuropsychologia ; 170: 108211, 2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35307368

RESUMO

Obsessive-Compulsive Disorder (OCD) is a debilitating disorder causing marked distress and functional impairment. While advances in behavioral and pharmacotherapies have been effective for a majority of patients with OCD, 10-30% remain treatment refractory and severely impaired. For a subset of treatment-resistant individuals with the most severe and disabling (intractable) illness, gamma ventral capsulotomy (GVC) appears effective in reducing OCD symptoms and functional impairment. However, the effects of the ventral internal capsule lesion via GVC surgery on executive function in everyday life have been minimally investigated. Examining behavioral outcomes of GVC also provides a rare opportunity to probe the functional importance of the ventral prefrontal-subcortical connections of the internal capsule white matter tract in a relatively homogenous sample of patients with comparable white matter lesions. The present study investigated changes in frontally-mediated behaviors, measured by the Frontal Systems Behavior Scale (FrSBe), following GVC in 45 individuals with severe and otherwise intractable OCD, as rated by patients themselves and family members. Linear mixed effects models revealed a significant improvement in patient self-ratings on the FrSBe after surgery, while family ratings did not significantly change. Interestingly, improvement on the FrSBe for both self and family raters was significantly correlated with improvement in OCD symptomatology post-surgery, as measured by the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). At the group level, we found no evidence of decline in frontally-mediated behaviors assessed by the FrSBe as a result of focal white matter disconnection via GVC. However, we cannot rule out the possibility that placebo effects or compromised patient self-awareness or insight contributed to the significant improvement in self ratings. Our measures may also have limited sensitivity to more selective impairments that could result from a small lesion to the ventral internal capsule. The present study demonstrates the need for detailed investigation of cognitive and behavioral changes as important factors when considering GVC as a viable treatment option for patients with refractory OCD.


Assuntos
Transtorno Obsessivo-Compulsivo , Radiocirurgia , Função Executiva , Humanos , Cápsula Interna/diagnóstico por imagem , Cápsula Interna/cirurgia , Transtorno Obsessivo-Compulsivo/cirurgia , Resultado do Tratamento
5.
Nature ; 576(7786): 311-314, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31802001

RESUMO

Oxygenic photosynthesis supplies organic carbon to the modern biosphere, but it is uncertain when this metabolism originated. It has previously been proposed1,2 that photosynthetic reaction centres capable of splitting water arose by about 3 billion years ago on the basis of the inferred presence of manganese oxides in Archaean sedimentary rocks. However, this assumes that manganese oxides can be produced only in the presence of molecular oxygen3, reactive oxygen species4,5 or by high-potential photosynthetic reaction centres6,7. Here we show that communities of anoxygenic photosynthetic microorganisms biomineralize manganese oxides in the absence of molecular oxygen and high-potential photosynthetic reaction centres. Microbial oxidation of Mn(II) under strictly anaerobic conditions during the Archaean eon would have produced geochemical signals identical to those used to date the evolution of oxygenic photosynthesis before the Great Oxidation Event1,2. This light-dependent process may also produce manganese oxides in the photic zones of modern anoxic water bodies and sediments.


Assuntos
Lagos/microbiologia , Manganês/metabolismo , Anaerobiose , Biofilmes , Luz , Oxirredução , Difração de Raios X
6.
J Bacteriol ; 199(21)2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28808129

RESUMO

The laboratory strain of Pseudomonas aeruginosa, PAO1, activates genes for catabolism of adenosine using quorum sensing (QS). However, this strain is not well-adapted for growth on adenosine, with doubling times greater than 40 h. We previously showed that when PAO1 is grown on adenosine and casein, variants emerge that grow rapidly on adenosine. To understand the mechanism by which this adaptation occurs, we performed whole-genome sequencing of five isolates evolved for rapid growth on adenosine. All five genomes had a gene duplication-amplification (GDA) event covering several genes, including the quorum-regulated nucleoside hydrolase gene, nuh, and PA0148, encoding an adenine deaminase. In addition, two of the growth variants also exhibited a nuh promoter mutation. We recapitulated the rapid growth phenotype with a plasmid containing six genes common to all the GDA events. We also showed that nuh and PA0148, the two genes at either end of the common GDA, were sufficient to confer rapid growth on adenosine. Additionally, we demonstrated that the variant nuh promoter increased basal expression of nuh but maintained its QS regulation. Therefore, GDA in P. aeruginosa confers the ability to grow efficiently on adenosine while maintaining QS regulation of nucleoside catabolism.IMPORTANCEPseudomonas aeruginosa thrives in many habitats and is an opportunistic pathogen of humans. In these diverse environments, P. aeruginosa must adapt to use myriad potential carbon sources. P. aeruginosa PAO1 cannot grow efficiently on nucleosides, including adenosine; however, it can acquire this ability through genetic adaptation. We show that the mechanism of adaptation is by amplification of a specific region of the genome and that the amplification preserves the regulation of the adenosine catabolic pathway by quorum sensing. These results demonstrate an underexplored mechanism of adaptation by P. aeruginosa, with implications for phenotypes such as development of antibiotic resistance.


Assuntos
Adenosina/metabolismo , Aminoidrolases/genética , Duplicação Gênica , N-Glicosil Hidrolases/genética , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/fisiologia , Adaptação Biológica , Aminoidrolases/metabolismo , Meios de Cultura/química , Análise Mutacional de DNA , Genoma Bacteriano , N-Glicosil Hidrolases/metabolismo , Plasmídeos , Regiões Promotoras Genéticas , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/genética , Análise de Sequência de DNA
7.
Mol Cancer Res ; 13(1): 186-96, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25189354

RESUMO

UNLABELLED: Understanding the molecular mechanisms behind formation of melanoma, the deadliest form of skin cancer, is crucial for improved diagnosis and treatment. One key is to better understand the cross-talk between epidermal keratinocytes and pigment-producing melanocytes. Here, using a bigenic mouse model system combining mutant oncogenic NRAS(Q61K) (constitutively active RAS) or mutant activated CDK4(R24C/R24C) (prevents binding of CDK4 by kinase inhibitor p16(INK4A)) with an epidermis-specific knockout of the nuclear retinoid X receptor alpha (RXRα(ep-/-)) results in increased melanoma formation after chronic ultraviolet-B (UVB) irradiation compared with control mice with functional RXRα. Melanomas from both groups of bigenic RXRα(ep-/-) mice are larger in size with higher proliferative capacity, and exhibit enhanced angiogenic properties and increased expression of malignant melanoma markers. Analysis of tumor adjacent normal skin from these mice revealed altered expression of several biomarkers indicative of enhanced melanoma susceptibility, including reduced expression of tumor suppressor p53 and loss of PTEN, with concomitant increase in activated AKT. Loss of epidermal RXRα in combination with UVB significantly enhances invasion of melanocytic cells to draining lymph nodes in bigenic mice expressing oncogenic NRAS(Q61K) compared with controls with functional RXRα. These results suggest a crucial role of keratinocytic RXRα to suppress formation of UVB-induced melanomas and their progression to malignant cancers in the context of driver mutations such as activated CDK4(R24C/R24C) or oncogenic NRAS(Q61K). IMPLICATIONS: These findings suggest that RXRα may serve as a clinical diagnostic marker and therapeutic target in melanoma progression and metastasis.


Assuntos
Quinase 4 Dependente de Ciclina/genética , GTP Fosfo-Hidrolases/genética , Melanoma/genética , Proteínas de Membrana/genética , PTEN Fosfo-Hidrolase/biossíntese , Receptor X Retinoide alfa/genética , Proteína Supressora de Tumor p53/biossíntese , Animais , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Queratinócitos/patologia , Queratinócitos/efeitos da radiação , Melanoma/patologia , Camundongos , Mutação , Microambiente Tumoral/genética , Microambiente Tumoral/efeitos da radiação , Raios Ultravioleta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA