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1.
Epilepsia Open ; 9(5): 1981-1996, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39177045

RESUMO

Lifestyle interventions are strategies used to self-manage medical conditions, such as epilepsy, and often complement traditional pharmacologic and surgical therapies. The need for integrating evidence-based lifestyle interventions into mainstream medicine for the treatment of epilepsy is evident given that despite the availability of a multitude of treatments with medications and surgical techniques, a significant proportion of patients have refractory seizures, and even those who are seizure-free report significant adverse effects with current treatments. Although the evidence base for complementary medicine is less robust than it is for traditional forms of medicine, the evidence to date suggests that several forms of complementary medicine including yoga, mindfulness meditation, cognitive behavioral therapy, diet and nutrition, exercise and memory rehabilitation, and music therapy may have important roles as adjuncts in the treatment armamentarium for epilepsy. These topics were discussed by a diverse group of medical providers and scientists at the "Lifestyle Intervention for Epilepsy (LIFE)" symposium hosted by Cleveland Clinic. PLAIN LANGUAGE SUMMARY: There are many people with epilepsy who continue to have seizures even though they are being treated with medication or brain surgery. Even after seizures stop, some may experience medication side effects. There is research to suggest that certain lifestyle changes, such as yoga, mindfulness, exercise, music therapy, and adjustments to diet, could help people with epilepsy, when used along with routine treatment. Experts discussed the latest research at the "Lifestyle Intervention for Epilepsy (LIFE)" symposium hosted by Cleveland Clinic.


Assuntos
Epilepsia , Estilo de Vida , Humanos , Epilepsia/terapia , Terapias Complementares , Yoga , Exercício Físico , Atenção Plena
2.
Circ Res ; 135(7): 739-754, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39140440

RESUMO

BACKGROUND: Transverse (t)-tubules drive the rapid and synchronous Ca2+ rise in cardiac myocytes. The virtual complete atrial t-tubule loss in heart failure (HF) decreases Ca2+ release. It is unknown if or how atrial t-tubules can be restored and how this affects systolic Ca2+. METHODS: HF was induced in sheep by rapid ventricular pacing and recovered following termination of rapid pacing. Serial block-face scanning electron microscopy and confocal imaging were used to study t-tubule ultrastructure. Function was assessed using patch clamp, Ca2+, and confocal imaging. Candidate proteins involved in atrial t-tubule recovery were identified by western blot and expressed in rat neonatal ventricular myocytes to determine if they altered t-tubule structure. RESULTS: Atrial t-tubules were lost in HF but reappeared following recovery from HF. Recovered t-tubules were disordered, adopting distinct morphologies with increased t-tubule length and branching. T-tubule disorder was associated with mitochondrial disorder. Recovered t-tubules were functional, triggering Ca2+ release in the cell interior. Systolic Ca2+, ICa-L, sarcoplasmic reticulum Ca2+ content, and sarcoendoplasmic reticulum Ca2+ ATPase function were restored following recovery from HF. Confocal microscopy showed fragmentation of ryanodine receptor staining and movement away from the z-line in HF, which was reversed following recovery from HF. Acute detubulation, to remove recovered t-tubules, confirmed their key role in restoration of the systolic Ca2+ transient, the rate of Ca2+ removal, and the peak L-type Ca2+ current. The abundance of telethonin and myotubularin decreased during HF and increased during recovery. Transfection with these proteins altered the density and structure of tubules in neonatal myocytes. Myotubularin had a greater effect, increasing tubule length and branching, replicating that seen in the recovery atria. CONCLUSIONS: We show that recovery from HF restores atrial t-tubules, and this promotes recovery of ICa-L, sarcoplasmic reticulum Ca2+ content, and systolic Ca2+. We demonstrate an important role for myotubularin in t-tubule restoration. Our findings reveal a new and viable therapeutic strategy.


Assuntos
Átrios do Coração , Insuficiência Cardíaca , Miócitos Cardíacos , Animais , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Miócitos Cardíacos/ultraestrutura , Átrios do Coração/metabolismo , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Ovinos , Cálcio/metabolismo , Sinalização do Cálcio , Ratos , Retículo Sarcoplasmático/metabolismo , Retículo Sarcoplasmático/ultraestrutura , Retículo Sarcoplasmático/patologia , Recuperação de Função Fisiológica , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/ultraestrutura , Mitocôndrias Cardíacas/patologia , Células Cultivadas , Sístole , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Ratos Sprague-Dawley , Feminino
3.
Curr Res Food Sci ; 9: 100808, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39149527

RESUMO

Introducing particles as additives, specifically engineered nanoparticles, in the food industry has improved food properties. Since 2014, alongside the presence of these added particles, there has been a mandatory requirement to disclose if those additives are nanomaterials in the ingredient list of food products. However, detecting and characterizing nanomaterials is time-consuming due to their small sizes, low concentrations, and diverse food matrices. We present a streamlined analytical process to detect the presence of silica and titania particles in food, applicable for food regulation and control. Using X-ray Fluorescence Spectrometry for screening enables quick categorization of inorganic particles labeling accuracy, distinguishing products with and without them. For the former, we develop matrix-independent digestion and introduce time-effective statistics to evaluate the median particle size using a reduced number of particles counted, ensuring accurate "nano" labeling. Through the implementation of this work, our objective is to simplify and facilitate verifying the proper labeling of food products.

4.
Am J Physiol Heart Circ Physiol ; 327(3): H631-H638, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39028283

RESUMO

Chondroitin sulfate proteoglycans (CSPGs) inhibit sympathetic reinnervation in rodent hearts post-myocardial infarction (MI), causing regional hypoinnervation that is associated with supersensitivity of ß-adrenergic receptors and increased arrhythmia susceptibility. To investigate the role of CSPGs and hypoinnervation in the heart of larger mammals, we used a rabbit model of reperfused MI and tested electrophysiological responses to sympathetic nerve stimulation (SNS). Innervated hearts from MI and sham rabbits were optically mapped using voltage and Ca2+-sensitive dyes. SNS was performed with electrical stimulation of the spinal cord, and ß-adrenergic responsiveness was tested using isoproterenol. Sympathetic nerve density and CSPG expression were evaluated using immunohistochemistry. CSPGs were robustly expressed in the infarct region of all MI hearts, and the presence of CSPGs was associated with reduced sympathetic nerve density in the infarct versus remote region. Action potential duration (APD) dispersion and tendency for induction of ventricular tachycardia/fibrillation (VT/VF) were increased with SNS in MI but not sham hearts. SNS decreased APD at 80% repolarization (APD80) in MI but not sham hearts, whereas isoproterenol decreased APD80 in both groups. Isoproterenol also shortened Ca2+ transient duration at 80% repolarization in both groups but to a greater extent in MI hearts. Our data suggest that sympathetic remodeling post-MI is similar between rodents and rabbits, with CSPGs associated with sympathetic hypoinnervation. Despite a reduction in sympathetic nerve density, the infarct region of MI hearts remained responsive to both physiological SNS and isoproterenol, potentially through preserved or elevated ß-adrenergic responsiveness, which may underlie increased APD dispersion and tendency for VT/VF.NEW & NOTEWORTHY Here, we show that CSPGs are present in the infarcts of rabbit hearts with reperfused MI, where they are associated with reduced sympathetic nerve density. Despite hypoinnervation, sympathetic responsiveness is maintained or enhanced in MI rabbit hearts, which also demonstrate increased APD dispersion and tendency for arrhythmias following sympathetic modulation. Together, this study indicates that the mechanisms of sympathetic remodeling post-MI are similar between rodents and rabbits, with hypoinnervation likely associated with enhanced ß-adrenergic sensitivity.


Assuntos
Potenciais de Ação , Modelos Animais de Doenças , Infarto do Miocárdio , Sistema Nervoso Simpático , Animais , Coelhos , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Sistema Nervoso Simpático/fisiopatologia , Sistema Nervoso Simpático/metabolismo , Masculino , Isoproterenol/farmacologia , Agonistas Adrenérgicos beta/farmacologia , Coração/inervação , Coração/fisiopatologia , Miocárdio/metabolismo , Miocárdio/patologia , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/etiologia
5.
bioRxiv ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38895350

RESUMO

Chondroitin sulfate proteoglycans (CSPGs) inhibit sympathetic reinnervation in rodent hearts post myocardial infarction (MI), causing regional hypo-innervation that is associated with supersensitivity of ß-adrenergic receptors and increased arrhythmia susceptibility. To investigate the role of CSPGs and hypo-innervation in the heart of larger mammals, we used a rabbit model of reperfused MI and tested electrophysiological responses to sympathetic nerve stimulation (SNS). Innervated hearts from MI and sham rabbits were optically mapped using voltage and Ca 2+ -sensitive dyes. SNS was performed with electrical stimulation of the spinal cord and ß-adrenergic responsiveness was tested using isoproterenol. Sympathetic nerve density and CSPG expression were evaluated using immunohistochemistry. CSPGs were robustly expressed in the infarct and border zone of all MI hearts, and the presence of CSPGs was associated with reduced sympathetic nerve density in the infarct vs. remote region. Action potential duration (APD) dispersion and susceptibility to ventricular tachycardia/fibrillation (VT/VF) were increased with SNS in MI hearts but not in sham. SNS decreased APD 80 in MI but not sham hearts, while isoproterenol decreased APD 80 in both groups. Isoproterenol also shortened Ca 2+ transient duration (CaTD 80 ) in both groups but to a greater extent in MI hearts. Our data suggest sympathetic remodeling post-MI is similar between species, with CSPGs associated with sympathetic hypo-innervation. Despite a reduction in sympathetic nerve density, the infarct region of MI hearts remained responsive to both physiological SNS and isoproterenol, potentially through preserved or elevated ß-adrenergic responsiveness, which may underly increased APD dispersion and susceptibility for VT/VF. NEW & NOTEWORTHY: Here we show that CSPGs are present in the infarcts of rabbit hearts with reperfused MI, where they are associated with reduced sympathetic nerve density. Despite hypo-innervation, sympathetic responsiveness is maintained or enhanced in MI rabbit hearts, which also demonstrate increased APD dispersion and tendency for arrhythmias following sympathetic modulation. Together, this study indicates that the mechanisms of sympathetic remodeling post-MI are similar between species, with hypo-innervation likely associated with enhanced ß-adrenergic sensitivity.

6.
J Alzheimers Dis ; 100(3): 843-862, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38943387

RESUMO

Background: Computer-aided machine learning models are being actively developed with clinically available biomarkers to diagnose Alzheimer's disease (AD) in living persons. Despite considerable work with cross-sectional in vivo data, many models lack validation against postmortem AD neuropathological data. Objective: Train machine learning models to classify the presence or absence of autopsy-confirmed severe AD neuropathology using clinically available features. Methods: AD neuropathological status are assessed at postmortem for participants from the National Alzheimer's Coordinating Center (NACC). Clinically available features are utilized, including demographics, Apolipoprotein E(APOE) genotype, and cortical thicknesses derived from ante-mortem MRI scans encompassing AD meta regions of interest (meta-ROI). Both logistic regression and random forest models are trained to identify linearly and nonlinearly separable features between participants with the presence (N = 91, age-at-MRI = 73.6±9.24, 38 women) or absence (N = 53, age-at-MRI = 68.93±19.69, 24 women) of severe AD neuropathology. The trained models are further validated in an external data set against in vivo amyloid biomarkers derived from PET imaging (amyloid-positive: N = 71, age-at-MRI = 74.17±6.37, 26 women; amyloid-negative: N = 73, age-at-MRI = 71.59±6.80, 41 women). Results: Our models achieve a cross-validation accuracy of 84.03% in classifying the presence or absence of severe AD neuropathology, and an external-validation accuracy of 70.14% in classifying in vivo amyloid positivity status. Conclusions: Our models show that clinically accessible features, including APOE genotype and cortical thinning encompassing AD meta-ROIs, are able to classify both postmortem confirmed AD neuropathological status and in vivo amyloid status with reasonable accuracies. These results suggest the potential utility of AD meta-ROIs in determining AD neuropathological status in living persons.


Assuntos
Doença de Alzheimer , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Doença de Alzheimer/classificação , Feminino , Idoso , Masculino , Imageamento por Ressonância Magnética/métodos , Idoso de 80 Anos ou mais , Apolipoproteínas E/genética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Pessoa de Meia-Idade , Neuropatologia/métodos
7.
Mar Pollut Bull ; 203: 116468, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38744048

RESUMO

Detection of small plastic particles in environmental water samples has been a topic of increasing interest in recent years. A multitude of techniques, such as variants of Raman spectroscopy, have been employed to facilitate their analysis in such complex sample matrices. However, these studies are often conducted for a limited number of plastic types in matrices with relatively little additional materials. Thus, much remains unknown about what parameters influence the detection limits of Raman spectroscopy for more environmentally relevant samples. To address this, this study utilizes Raman spectroscopy to detect six plastic particle types; 161 and 33 nm polystyrene, < 450 nm and 36 nm poly(ethylene terephthalate), 121 nm polypropylene, and 126 nm polyethylene; spiked into artificial saltwater, artificial freshwater, North Sea, Thames River, and Elbe River water. Overall, factors such as plastic particle properties, water matrix composition, and experimental setup were shown to influence the final limits of detection.


Assuntos
Monitoramento Ambiental , Água Doce , Plásticos , Análise Espectral Raman , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Plásticos/análise , Água Doce/química , Água do Mar/química , Rios/química , Microplásticos/análise
8.
Cell Rep ; 43(5): 114128, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38652661

RESUMO

Shifts in the magnitude and nature of gut microbial metabolites have been implicated in Alzheimer's disease (AD), but the host receptors that sense and respond to these metabolites are largely unknown. Here, we develop a systems biology framework that integrates machine learning and multi-omics to identify molecular relationships of gut microbial metabolites with non-olfactory G-protein-coupled receptors (termed the "GPCRome"). We evaluate 1.09 million metabolite-protein pairs connecting 408 human GPCRs and 335 gut microbial metabolites. Using genetics-derived Mendelian randomization and integrative analyses of human brain transcriptomic and proteomic profiles, we identify orphan GPCRs (i.e., GPR84) as potential drug targets in AD and that triacanthine experimentally activates GPR84. We demonstrate that phenethylamine and agmatine significantly reduce tau hyperphosphorylation (p-tau181 and p-tau205) in AD patient induced pluripotent stem cell-derived neurons. This study demonstrates a systems biology framework to uncover the GPCR targets of human gut microbiota in AD and other complex diseases if broadly applied.


Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Receptores Acoplados a Proteínas G , Doença de Alzheimer/metabolismo , Doença de Alzheimer/microbiologia , Humanos , Receptores Acoplados a Proteínas G/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas tau/metabolismo , Proteômica/métodos , Fosforilação , Encéfalo/metabolismo , Neurônios/metabolismo , Multiômica
9.
Am J Physiol Heart Circ Physiol ; 326(6): H1337-H1349, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38551482

RESUMO

Nicotine is the primary addictive component of tobacco products. Through its actions on the heart and autonomic nervous system, nicotine exposure is associated with electrophysiological changes and increased arrhythmia susceptibility. To assess the underlying mechanisms, we treated rabbits with transdermal nicotine (NIC, 21 mg/day) or control (CT) patches for 28 days before performing dual optical mapping of transmembrane potential (RH237) and intracellular Ca2+ (Rhod-2 AM) in isolated hearts with intact sympathetic innervation. Sympathetic nerve stimulation (SNS) was performed at the first to third thoracic vertebrae, and ß-adrenergic responsiveness was additionally evaluated following norepinephrine (NE) perfusion. Baseline ex vivo heart rate (HR) and SNS stimulation threshold were higher in NIC versus CT (P = 0.004 and P = 0.003, respectively). Action potential duration alternans emerged at longer pacing cycle lengths (PCL) in NIC versus CT at baseline (P = 0.002) and during SNS (P = 0.0003), with similar results obtained for Ca2+ transient alternans. SNS shortened the PCL at which alternans emerged in CT but not in NIC hearts. NIC-exposed hearts tended to have slower and reduced HR responses to NE perfusion, but ventricular responses to NE were comparable between groups. Although fibrosis was unaltered, NIC hearts had lower sympathetic nerve density (P = 0.03) but no difference in NE content versus CT. These results suggest both sympathetic hypoinnervation of the myocardium and regional differences in ß-adrenergic responsiveness with NIC. This autonomic remodeling may contribute to the increased risk of arrhythmias associated with nicotine exposure, which may be further exacerbated with long-term use.NEW & NOTEWORTHY Here, we show that chronic nicotine exposure was associated with increased heart rate, increased susceptibility to alternans, and reduced sympathetic electrophysiological responses in the intact rabbit heart. We suggest that this was due to sympathetic hypoinnervation of the myocardium and diminished ß-adrenergic responsiveness of the sinoatrial node following nicotine treatment. Though these differences did not result in increased arrhythmia propensity in our study, we hypothesize that prolonged nicotine exposure may exacerbate this proarrhythmic remodeling.


Assuntos
Potenciais de Ação , Frequência Cardíaca , Coração , Nicotina , Sistema Nervoso Simpático , Animais , Nicotina/toxicidade , Nicotina/efeitos adversos , Coelhos , Frequência Cardíaca/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Coração/inervação , Coração/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Masculino , Agonistas Nicotínicos/toxicidade , Agonistas Nicotínicos/administração & dosagem , Sinalização do Cálcio/efeitos dos fármacos , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/fisiopatologia , Arritmias Cardíacas/metabolismo , Adesivo Transdérmico , Preparação de Coração Isolado , Administração Cutânea , Norepinefrina/metabolismo
10.
Environ Sci Nano ; 11(3): 1000-1011, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38496351

RESUMO

The presence of submicron- (1 µm-100 nm) and nanoplastic (<100 nm) particles within various sample matrices, ranging from marine environments to foods and beverages, has become a topic of increasing interest in recent years. Despite this interest, very few analytical techniques are known that allow for the detection of these small plastic particles in the low concentration ranges that they are anticipated to be present at. Research focused on optimizing surface-enhanced Raman scattering (SERS) to enhance signal obtained in Raman spectroscopy has been shown to have great potential for the detection of plastic particles below conventional resolution limits. In this study, we produce SERS substrates composed of gold nanostars and assess their potential for submicron- and nanoplastic detection. The results show 33 nm polystyrene could be detected down to 1.25 µg mL-1 while 36 nm poly(ethylene terephthalate) was detected down to 5 µg mL-1. These results confirm the promising potential of the gold nanostar-based SERS substrates for nanoplastic detection. Furthermore, combined with findings for 121 nm polypropylene and 126 nm polyethylene particles, they highlight potential differences in analytical performance that depend on the properties of the plastics being studied.

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