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1.
Epilepsia ; 64(9): 2499-2514, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37277947

RESUMO

OBJECTIVE: Ischemic stroke is one of the main causes of death and disability worldwide and currently has limited treatment options. Electroencephalography (EEG) signals are significantly affected in stroke patients during the acute stage. In this study, we preclinically characterized the brain electrical rhythms and seizure activity during the hyperacute and late acute phases in a hemispheric stroke model with no reperfusion. METHODS: EEG signals and seizures were studied in a model of hemispheric infarction induced by permanent occlusion of the middle cerebral artery (pMCAO), which mimics the clinical condition of stroke patients with permanent ischemia. Electrical brain activity was also examined using a photothrombotic (PT) stroke model. In the PT model, we induced a similar (PT group-1) or smaller (PT group-2) cortical lesion than in the pMCAO model. For all models, we used a nonconsanguineous mouse strain that mimics human diversity and genetic variation. RESULTS: The pMCAO hemispheric stroke model exhibited thalamic-origin nonconvulsive seizures during the hyperacute stage that propagated to the thalamus and cortex. The seizures were also accompanied by progressive slowing of the EEG signal during the acute phase, with elevated delta/theta, delta/alpha, and delta/beta ratios. Cortical seizures were also confirmed in the PT stroke model of similar lesions as in the pMCAO model, but not in the PT model of smaller injuries. SIGNIFICANCE: In the clinically relevant pMCAO model, poststroke seizures and EEG abnormalities were inferred from recordings of the contralateral hemisphere (noninfarcted hemisphere), emphasizing the reciprocity of interhemispheric connections and that injuries affecting one hemisphere had consequences for the other. Our results recapitulate many of the EEG signal hallmarks seen in stroke patients, thereby validating this specific mouse model for the examination of the mechanistic aspects of brain function and for the exploration of the reversion or suppression of EEG abnormalities in response to neuroprotective and anti-epileptic therapies.


Assuntos
Transtornos Cerebrovasculares , Acidente Vascular Cerebral , Humanos , Camundongos , Animais , Acidente Vascular Cerebral/complicações , Convulsões , Encéfalo , Eletroencefalografia/efeitos adversos , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/patologia , Tálamo
2.
Int J Mol Sci ; 24(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37958913

RESUMO

Magnetic hyperthermia (MHT) is an oncological therapy that uses magnetic nanoparticles (MNPs) to generate localized heat under a low-frequency alternating magnetic field (AMF). Recently, trapezoidal pulsed alternating magnetic fields (TPAMFs) have proven their efficacy in enhancing the efficiency of heating in MHT as compared to the sinusoidal one. Our study aims to compare the TPAMF waveform's killing effect against the sinusoidal waveform in B16F10 and CT2A cell lines to determine more efficient waveforms in causing cell death. For that purpose, we used MNPs and different AMF waveforms: trapezoidal (TP), almost-square (TS), triangular (TR), and sinusoidal signal (SN). MNPs at 1 and 4 mg/mL did not affect cell viability during treatment. The exposition of B16F10 and CT2A cells to only AMF showed nonsignificant mortality. Hence, the synergetic effect of the AMF and MNPs causes the observed cell death. Among the explored cases, the nonharmonic signals demonstrated better efficacy than the SN one as an MHT treatment. This study has revealed that the application of TP, TS, or TR waveforms is more efficient and has considerable capability to increase cancer cell death compared to the traditional sinusoidal treatment. Overall, we can conclude that the application of nonharmonic signals enhances MHT treatment efficiency against tumor cells.


Assuntos
Glioblastoma , Hipertermia Induzida , Nanopartículas de Magnetita , Melanoma , Humanos , Campos Eletromagnéticos , Glioblastoma/terapia , Nanopartículas de Magnetita/uso terapêutico , Campos Magnéticos , Hipertermia , Linhagem Celular
3.
Int J Mol Sci ; 23(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35806455

RESUMO

Brain stroke is a highly prevalent pathology and a main cause of disability among older adults. If not promptly treated with recanalization therapies, primary and secondary mechanisms of injury contribute to an increase in the lesion, enhancing neurological deficits. Targeting excitotoxicity and oxidative stress are very promising approaches, but only a few compounds have reached the clinic with relatively good positive outcomes. The exploration of novel targets might overcome the lack of clinical translation of previous efficient preclinical neuroprotective treatments. In this study, we examined the neuroprotective properties of 2-aminoethoxydiphenyl borate (2-APB), a molecule that interferes with intracellular calcium dynamics by the antagonization of several channels and receptors. In a permanent model of cerebral ischemia, we showed that 2-APB reduces the extent of the damage and preserves the functionality of the cortical territory, as evaluated by somatosensory evoked potentials (SSEPs). While in this permanent ischemia model, the neuroprotective effect exerted by the antioxidant scavenger cholesteronitrone F2 was associated with a reduction in reactive oxygen species (ROS) and better neuronal survival in the penumbra, 2-APB did not modify the inflammatory response or decrease the content of ROS and was mostly associated with a shortening of peri-infarct depolarizations, which translated into better cerebral blood perfusion in the penumbra. Our study highlights the potential of 2-APB to target spreading depolarization events and their associated inverse hemodynamic changes, which mainly contribute to extension of the area of lesion in cerebrovascular pathologies.


Assuntos
Isquemia Encefálica , Depressão Alastrante da Atividade Elétrica Cortical , Idoso , Boratos/farmacologia , Isquemia Encefálica/patologia , Circulação Cerebrovascular/fisiologia , Humanos , Infarto , Neuroproteção , Espécies Reativas de Oxigênio
4.
Molecules ; 27(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35807389

RESUMO

High-performance regenerated silkworm (Bombyx mori) silk fibers can be produced efficiently through the straining flow spinning (SFS) technique. In addition to an enhanced biocompatibility that results from the removal of contaminants during the processing of the material, regenerated silk fibers may be functionalized conveniently by using a range of different strategies. In this work, the possibility of implementing various functionalization techniques is explored, including the production of fluorescent fibers that may be tracked when implanted, the combination of the fibers with enzymes to yield fibers with catalytic properties, and the functionalization of the fibers with cell-adhesion motifs to modulate the adherence of different cell lineages to the material. When considered globally, all these techniques are a strong indication not only of the high versatility offered by the functionalization of regenerated fibers in terms of the different chemistries that can be employed, but also on the wide range of applications that can be covered with these functionalized fibers.


Assuntos
Bombyx , Fibroínas , Animais , Adesão Celular , Seda
5.
Nanotechnology ; 30(35): 355101, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31082814

RESUMO

Metallic nanorods are promising agents for a wide range of biomedical applications. We report an optical hyperthermia method capable of inducing slowdown tumor progression of an experimental in vivo CT-2A glioblastoma tumor. The tumor model used in this research is based on the transplantation of mouse astrocytoma CT-2A cells in the striatum of mice by intracranial stereotaxic surgery. Two weeks after cell implant, the resulting tumor is treated by irradiating intratumoral injected gold nanorods, biofunctionalized with CD133 antibody (B-GNRs), using a continuous wave laser. Nanoparticles convert the absorbed light into localized heat (reaching up to 44 °C) due to the effect of surface plasmon resonance. A significant slowdown in CT-2A tumor progression is evident, by histology and magnetic resonance imaging, at one (p = 0.03) and two weeks (p = 0.008) after irradiation treatment. A notable deceleration in tumor size (15%-75%) as compared to the control untreated groups, it is observed. Thus, laser irradiation of B-GNRs is found to be effective for the treatment of CT-2A tumor progression. Similarities between the pre-clinical CT-2A tumor model and the human astrocytoma disease, in terms of anatomy, metastatic behavior and histopathology, suggest that hyperthermic treatment by laser irradiation of B-GNRs administered into high-grade human astrocytoma might constitute a promising alternative treatment to limit the progression of this deadly disease.


Assuntos
Astrocitoma/terapia , Neoplasias Encefálicas/terapia , Ouro/farmacologia , Hipertermia Induzida/métodos , Terapia a Laser/métodos , Nanotubos/química , Antígeno AC133/antagonistas & inibidores , Antígeno AC133/imunologia , Animais , Anticorpos Neutralizantes/farmacologia , Astrocitoma/imunologia , Astrocitoma/patologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Ouro/administração & dosagem , Ouro/química , Humanos , Injeções Intralesionais , Lasers , Camundongos , Camundongos Endogâmicos C57BL , Nanotubos/ultraestrutura , Transplante de Neoplasias , Técnicas Estereotáxicas , Ressonância de Plasmônio de Superfície , Carga Tumoral/efeitos da radiação
6.
Nanotechnology ; 29(38): 385705, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-29947336

RESUMO

Biomedical applications based on the magnetic properties of superparamagnetic iron oxide nanoparticles (SPIONs) may be altered by the mechanical attachment or cellular uptake of these nanoparticles. When nanoparticles interact with living cells, they are captured and internalized into intracellular compartments. Consequently, the magnetic behavior of the nanoparticles is modified. In this paper, we investigated the change in the magnetic response of 14 nm magnetic nanoparticles (Fe3O4) in different solutions, both as a stable liquid suspension (one of them mimicking the cellular cytoplasm) and when associated with cells. The field-dependent magnetization curves from inert fluids and cell cultures were determined by using an alternating gradient magnetometer, MicroMagTM 2900. The equipment was adapted to measure liquid samples because it was originally designed only for solids. In order to achieve this goal, custom sample holders were manufactured. Likewise, the nuclear magnetic relaxation dispersion profiles for the inert fluid were also measured by fast field cycling nuclear magnetic relaxation relaxometry. The results show that SPION magnetization in inert fluids was affected by the carrier liquid viscosity and the concentration. In cell cultures, the mechanical attachment or confinement of the SPIONs inside the cells accounted for the change in the dynamic magnetic behavior of the nanoparticles. Nevertheless, the magnetization value in the cell cultures was slightly lower than that of the fluid simulating the viscosity of cytoplasm, suggesting that magnetization loss was not only due to medium viscosity but also to a reduction in the mechanical degrees of freedom of SPIONs rotation and translation inside cells. The findings presented here provide information on the loss of magnetic properties when nanoparticles are suspended in viscous fluids or internalized in cells. This information could be exploited to improve biomedical applications based on magnetic properties such as magnetic hyperthermia, contrast agents and drug delivery.


Assuntos
Fibroínas/química , Nanopartículas de Magnetita/química , Seda/química , Células 3T3 , Animais , Células Cultivadas , Citoplasma/química , Compostos Férricos/química , Fibroblastos/química , Campos Magnéticos , Magnetismo/métodos , Camundongos , Suspensões/química , Viscosidade
7.
Anal Chem ; 86(15): 7383-90, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25001419

RESUMO

This work presents the first application of total-reflection X-ray fluorescence (TXRF) spectrometry, a new and powerful alternative analytical method, to evaluation of the bioaccumulation kinetics of gold nanorods (GNRs) in various tissues upon intravenous administration in mice. The analytical parameters for developed methodology by TXRF were evaluated by means of the parallel analysis of bovine liver certified reference material samples (BCR-185R) doped with 10 µg/g gold. The average values (n = 5) achieved for gold measurements in lyophilized tissue weight were as follows: recovery 99.7%, expanded uncertainty (k = 2) 7%, repeatability 1.7%, detection limit 112 ng/g, and quantification limit 370 ng/g. The GNR bioaccumulation kinetics was analyzed in several vital mammalian organs such as liver, spleen, brain, and lung at different times. Additionally, urine samples were analyzed to study the kinetics of elimination of the GNRs by this excretion route. The main achievement was clearly differentiating two kinds of behaviors. GNRs were quickly bioaccumulated by highly vascular filtration organs such as liver and spleen, while GNRs do not show a bioaccumulation rates in brain and lung for the period of time investigated. In parallel, urine also shows a lack of GNR accumulation. TXRF has proven to be a powerful, versatile, and precise analytical technique for the evaluation of GNRs content in biological systems and, in a more general way, for any kind of metallic nanoparticles.


Assuntos
Ouro/farmacocinética , Nanotubos , Espectrometria por Raios X/métodos , Animais , Ouro/química , Cinética , Camundongos
8.
ATS Sch ; 5(2): 259-273, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38957494

RESUMO

Background: A lack of high-quality provider education hinders the delivery of standard-of-care delirium detection and prevention practices in the intensive care unit (ICU). To fill this gap, we developed and validated an e-learning ICU Delirium Playbook consisting of eight videos and a 44-question knowledge assessment quiz. Given the increasing Spanish-speaking population worldwide, we translated and cross-culturally adapted the playbook from English into Spanish. Objective: To translate and culturally adapt the ICU Delirium Playbook into Spanish, the second most common native language worldwide. Methods: The translation and cross-cultural adaptation process included double forward and back translations and harmonization by a 14-person interdisciplinary team of ICU nurses and physicians, delirium experts, methodologists, medical interpreters, and bilingual professionals representing many Spanish-speaking global regions. After a preeducation quiz, a nurse focus group completed the playbook videos and posteducation quiz, followed by a semistructured interview. Results: The ICU Delirium Playbook: Spanish Version maintained conceptual equivalence to the English version. Focus group participants posted mean (standard deviation) pre- and post-playbook scores of 63% (10%) and 78% (12%), with a 15% (11%) pre-post improvement (P = 0.01). Participants reported improved perceived competency in performing the Confusion Assessment Method for the ICU and provided positive feedback regarding the playbook. Conclusion: After translation and cultural adaptation, the ICU Delirium Playbook: Spanish Version yielded significant knowledge assessment improvements and positive feedback. The Spanish playbook is now available for public dissemination.

9.
Biomimetics (Basel) ; 8(1)2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36810396

RESUMO

After an injury, the limited regenerative capacity of the central nervous system makes the reconnection and functional recovery of the affected nervous tissue almost impossible. To address this problem, biomaterials appear as a promising option for the design of scaffolds that promote and guide this regenerative process. Based on previous seminal works on the ability of regenerated silk fibroin fibers spun through the straining flow spinning (SFS) technique, this study is intended to show that the usage of functionalized SFS fibers allows an enhancement of the guidance ability of the material when compared with the control (nonfunctionalized) fibers. It is shown that the axons of the neurons not only tend to follow the path marked by the fibers, in contrast to the isotropic growth observed on conventional culture plates, but also that this guidance can be further modulated through the biofunctionalization of the material with adhesion peptides. Establishing the guidance ability of these fibers opens the possibility of their use as implants for spinal cord injuries, so that they may represent the core of a therapy that would allow the reconnection of the injured ends of the spinal cord.

10.
Polymers (Basel) ; 15(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37299290

RESUMO

Central nervous system (CNS) diseases represent an extreme burden with significant social and economic costs. A common link in most brain pathologies is the appearance of inflammatory components that can jeopardize the stability of the implanted biomaterials and the effectiveness of therapies. Different silk fibroin scaffolds have been used in applications related to CNS disorders. Although some studies have analyzed the degradability of silk fibroin in non-cerebral tissues (almost exclusively upon non-inflammatory conditions), the stability of silk hydrogel scaffolds in the inflammatory nervous system has not been studied in depth. In this study, the stability of silk fibroin hydrogels exposed to different neuroinflammatory contexts has been explored using an in vitro microglial cell culture and two in vivo pathological models of cerebral stroke and Alzheimer's disease. This biomaterial was relatively stable and did not show signs of extensive degradation across time after implantation and during two weeks of in vivo analysis. This finding contrasted with the rapid degradation observed under the same in vivo conditions for other natural materials such as collagen. Our results support the suitability of silk fibroin hydrogels for intracerebral applications and highlight the potentiality of this vehicle for the release of molecules and cells for acute and chronic treatments in cerebral pathologies.

11.
Crit Care Explor ; 5(7): e0939, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37457918

RESUMO

Although delirium detection and prevention practices are recommended in critical care guidelines, there remains a persistent lack of effective delirium education for ICU providers. To address this knowledge-practice gap, we developed an "ICU Delirium Playbook" to educate providers on delirium detection (using the Confusion Assessment Method for the ICU) and prevention. DESIGN: Building on our previous ICU Delirium Video Series, our interdisciplinary team developed a corresponding quiz to form a digital "ICU Delirium Playbook." Playbook content validity was evaluated by delirium experts, and face validity by an ICU nurse focus group. Additionally, focus group participants completed the quiz before and after video viewing. Remaining focus group concerns were evaluated in semi-structured follow-up interviews. SETTING: Online validation survey, virtual focus group, and virtual interviews. SUBJECTS: The validation group included six delirium experts in the fields of critical care, geriatrics, nursing, and ICU education. The face validation group included nine ICU nurses, three of whom participated in the semi-structured feedback interviews. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The 44-question quiz had excellent content validity (average scale-level content validity index [S-CVI] of individual items = 0.99, universal agreement S-CVI = 0.93, agreement κ ≥ 0.75, and clarity p ≥ 0.8). The focus group participants completed the Playbook in an average (sd) time of 53 (14) minutes, demonstrating significant improvements in pre-post quiz scores (74% vs 86%; p = 0.0009). Verbal feedback highlighted the conciseness, utility, and relevance of the Playbook, with all participants agreeing to deploy the digital education module in their ICUs. CONCLUSIONS: The ICU Delirium Playbook is a novel, first-of-its-kind asynchronous digital education tool aimed to standardize delirium detection and prevention practices. After a rigorous content and face validation process, the Playbook is now available for widespread use.

12.
P R Health Sci J ; 41(3): 111-116, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36018737

RESUMO

OBJECTIVE: To evaluate at-home opioid and benzodiazepine use, the degrees of pain and anxiety, and the incidence of probable withdrawal in post-discharge Trauma Intensive Care Unit (TICU) survivors. METHODS: This was an exploratory study of post-TICU survivors who had participated in a previous study of opioid and benzodiazepine withdrawal. We surveyed survivors by telephone asking for retrospective information (during their first 4-months postdischarge- Time 1) and current information (around 2-years post-discharge- Time 2). RESULTS: A mostly male (82%), young (median 38 years [IQR, 28-52]) sample of 27 TICU survivors reported using opioids (56%) at Time 1 for a median of 30 (IQR,14-90) days. Twelve percent of 26 survivors were still using opioids at Time 2. Sixty percent of the survivors had pain during Time 1, a median pain score of 6 (IQR, 5-8) on a 0-10 numeric rating scale (NRS).; 57% had pain at Time 2, median NRS score=6 (IQR, 4-7). Sixty-five percent of survivors had anxiety during Time 1, NRS median=7 (IQR, 5-9); 50% had anxiety at Time 2, NRS median= 6 (IQR, 3-7). At Time 1, 26% used prescribed benzodiazepines, and 12% used benzodiazepines at Time 2. Five and one of the 27 patients reported symptoms of opioid or benzodiazepine withdrawal, respectively, upon discontinuation or weaning. CONCLUSION: Many TICU survivors had discontinued opioid/benzodiazepine prescriptions by 4-months post discharge while half reporting pain/anxiety for up to 2-years. Investigating the effects of acute-to-chronic pain in ICU survivors and gaining a better understanding of the mechanisms of prolonged opioid use are warranted.


Assuntos
Analgésicos Opioides , Benzodiazepinas , Assistência ao Convalescente , Ansiedade , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Dor , Alta do Paciente , Estudos Retrospectivos , Sobreviventes
13.
J Biol Chem ; 285(13): 9881-9897, 2010 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-20106970

RESUMO

Human neural stem cells derived from the ventral mesencephalon (VM) are powerful research tools and candidates for cell therapies in Parkinson disease. Previous studies with VM dopaminergic neuron (DAn) precursors indicated poor growth potential and unstable phenotypical properties. Using the model cell line hVM1 (human ventral mesencephalic neural stem cell line 1; a new human fetal VM stem cell line), we have found that Bcl-X(L) enhances the generation of DAn from VM human neural stem cells. Mechanistically, Bcl-X(L) not only exerts the expected antiapoptotic effect but also induces proneural (NGN2 and NEUROD1) and dopamine-related transcription factors, resulting in a high yield of DAn with the correct phenotype of substantia nigra pars compacta (SNpc). The expression of key genes directly involved in VM/SNpc dopaminergic patterning, differentiation, and maturation (EN1, LMX1B, PITX3, NURR1, VMAT2, GIRK2, and dopamine transporter) is thus enhanced by Bcl-X(L). These effects on neurogenesis occur in parallel to a decrease in glia generation. These in vitro Bcl-X(L) effects are paralleled in vivo, after transplantation in hemiparkinsonian rats, where hVM1-Bcl-X(L) cells survive, integrate, and differentiate into DAn, alleviating behavioral motor asymmetry. Bcl-X(L) then allows for human fetal VM stem cells to stably generate mature SNpc DAn both in vitro and in vivo and is thus proposed as a helpful factor for the development of cell therapies for neurodegenerative conditions, Parkinson disease in particular.


Assuntos
Dopamina/metabolismo , Neurônios/metabolismo , Células-Tronco/citologia , Proteína bcl-X/metabolismo , Animais , Apoptose , Comportamento Animal , Diferenciação Celular , Linhagem Celular , Modelos Animais de Doenças , Feminino , Humanos , Técnicas In Vitro , Potenciais da Membrana , Doença de Parkinson , Fenótipo , Ratos , Ratos Sprague-Dawley , Substância Negra/metabolismo
14.
J Neurosci Res ; 89(12): 2008-17, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21608011

RESUMO

The aralar/AGC1 knockout (KO) mouse shows a drastic decrease in brain aspartate and N-acetylaspartate levels and global hypomyelination, which are attributed to the lack of neuron-produced NAA used by oligodendrocytes as precursor of myelin lipid synthesis. In addition, these mice have a gradual drop in brain glutamine synthesis. We show here that hypomyelination is more pronounced in gray than in white matter regions. We find a lack of neurofilament-labelled processes in hypomyelinated fiber tracks from cerebral cortex but not from those of the cerebellar granule cell layer, which correspond to Purkinje neurons. Therefore, the impaired development or degeneration of neuronal processes in cerebral cortex is independent of hypomyelination. An increase in O4-labelled, immature oligodendrocytes is observed in gray and white matter regions of the aralar KO brain, suggesting a block in maturation compatible with the lack of NAA supplied by neurons. However, no defects in oligodendrocyte maturation were observed in in-vitro-cultured mixed astroglial cultures. We conclude that the primary defect of pyramidal neurons in cerebral cortex is possibly associated with a progressive failure in glutamatergic neurotransmission and may be among the main causes of the pathology of aralar/AGC1 deficiency.


Assuntos
Encéfalo/patologia , Proteínas de Transporte da Membrana Mitocondrial/deficiência , Bainha de Mielina/patologia , Oligodendroglia/patologia , Transmissão Sináptica/genética , Animais , Encéfalo/metabolismo , Células Cultivadas , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Transporte da Membrana Mitocondrial/genética , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo
15.
Brain Sci ; 11(3)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673399

RESUMO

During the transition from neonate to adulthood, brain maturation establishes coherence between behavioral states-wakefulness, non-rapid eye movement, and rapid eye movement sleep. In animal models few studies have characterized and analyzed cerebral rhythms and the sleep-wake cycle in early ages, in relation to adulthood. Since the analysis of sleep in early ages can be used as a predictive model of brain development and the subsequent emergence of neural disturbances in adults, we performed a study on late neonatal mice, an age not previously characterized. We acquired longitudinal 24 h electroencephalogram and electromyogram recordings and performed time and spectral analyses. We compared both age groups and found that late neonates: (i) spent more time in wakefulness and less time in non-rapid eye movement sleep, (ii) showed an increased relative band power in delta, which, however, reduced in theta during each behavioral state, (iii) showed a reduced relative band power in beta during wakefulness and non-rapid eye movement sleep, and (iv) manifested an increased total power over all frequencies. The data presented here might have implications expanding our knowledge of cerebral rhythms in early ages for identification of potential biomarkers in preclinical models of neurodegeneration.

16.
Nanomaterials (Basel) ; 11(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34947589

RESUMO

For decades now, conventional sinusoidal signals have been exclusively used in magnetic hyperthermia as the only alternating magnetic field waveform to excite magnetic nanoparticles. However, there are no theoretical nor experimental reasons that prevent the use of different waveforms. The only justifiable motive behind using the sinusoidal signal is its availability and the facility to produce it. Following the development of a configurable alternating magnetic field generator, we aim to study the effect of various waveforms on the heat production effectiveness of magnetic nanoparticles, seeking to prove that signals with more significant slope values, such as the trapezoidal and almost-square signals, allow the nanoparticles to reach higher efficiency in heat generation. Furthermore, we seek to point out that the nanoparticle power dissipation is dependent on the waveform's slope and not only the frequency, magnetic field intensity and the nanoparticle size. The experimental results showed a remarkably higher heat production performance of the nanoparticles when exposed to trapezoidal and almost-square signals than conventional sinusoidal signals. We conclude that the nanoparticles respond better to the trapezoidal and almost-square signals. On the other hand, the experimental results were used to calculate the normalized power dissipation value and prove its dependency on the slope. However, adjustments are necessary to the coil before proceeding with in vitro and in vivo studies to handle the magnetic fields required.

17.
Exp Cell Res ; 315(11): 1860-74, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19327351

RESUMO

Neural stem cells (NSCs) are powerful research tools for the design and discovery of new approaches to cell therapy in neurodegenerative diseases like Parkinson's disease. Several epigenetic and genetic strategies have been tested for long-term maintenance and expansion of these cells in vitro. Here we report the generation of a new stable cell line of human neural stem cells derived from ventral mesencephalon (hVM1) based on v-myc immortalization. The cells expressed neural stem cell and radial glia markers like nestin, vimentin and 3CB2 under proliferation conditions. After withdrawal of growth factors, proliferation and expression of v-myc were dramatically reduced and the cells differentiated into astrocytes, oligodendrocytes and neurons. hVM1 cells yield a large number of dopaminergic neurons (about 12% of total cells are TH+) after differentiation, which also produce dopamine. In addition to proneural genes (NGN2, MASH1), differentiated cells show expression of several genuine mesencephalic dopaminergic markers such as: LMX1A, LMX1B, GIRK2, ADH2, NURR1, PITX3, VMAT2 and DAT, indicating that they retain their regional identity. Our data indicate that this cell line and its clonal derivatives may constitute good candidates for the study of development and physiology of human dopaminergic neurons in vitro, and to develop tools for Parkinson's disease cell replacement preclinical research and drug testing.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Astrócitos/citologia , Astrócitos/metabolismo , Técnicas de Cultura de Células/métodos , Ciclo Celular , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Células Clonais/citologia , Células Clonais/metabolismo , Dopamina/metabolismo , Epigênese Genética , Expressão Gênica , Genes myc , Humanos , Mesencéfalo/citologia , Mesencéfalo/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transformação Genética
18.
Am J Crit Care ; 29(3): 226-232, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32355973

RESUMO

BACKGROUND: The Critical-Care Pain Observation Tool (CPOT) is recommended for evaluating pain behaviors in patients in the intensive care unit who are unable to report pain. The source of the only published Spanish version of the CPOT does not verify that it underwent a formal translation process. OBJECTIVE: To describe the translation into Spanish and cultural adaptation of the original French version of the CPOT. METHODS: Key persons in the translation process included one with a master's degree in translation, a critical care physician, nurse faculty members with vast experience in intensive care units, and the instrument's developer. This team followed the Principles of Good Practice for the Translation and Cultural Adaptation Process for Patient-Reported Outcomes Measures as a guide to translate and culturally adapt the CPOT. RESULTS: The first Spanish-language version was back translated to French and was also compared with the English version. Revisions necessitated a second version, which was submitted to experts in critical care. Their modifications required a third version, which was back translated to French and discussed with the CPOT developer, after which a fourth version was created. Finally, a linguistic expert proofread the tool, and the translation leaders incorporated the recommendations, thereby obtaining a final Spanish version. CONCLUSION: The Spanish version is ready to undergo validation with patients in the intensive care unit, which is the next step toward its use in assessing pain behaviors among patients in intensive care units where Spanish is spoken.


Assuntos
Unidades de Terapia Intensiva/organização & administração , Idioma , Medição da Dor/métodos , Medição da Dor/normas , Traduções , Cuidados Críticos/métodos , Cuidados Críticos/normas , Características Culturais , Humanos , Unidades de Terapia Intensiva/normas , Reprodutibilidade dos Testes
19.
Crit Care Explor ; 2(4): e0089, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32426731

RESUMO

Trauma ICU patients may require high and/or prolonged doses of opioids and/or benzodiazepines as part of their treatment. These medications may contribute to drug physical dependence, a response manifested by withdrawal syndrome. We aimed to identify risk factors, symptoms, and clinical variables associated with probable withdrawal syndrome. DESIGN: Prospective exploratory observational study. SETTING: Trauma ICU in large medical center in Puerto Rico. PARTICIPANTS: Fifty patients who received opioids and/or benzodiazepines for greater than or equal to 5 days. MEASUREMENTS AND MAIN RESULTS: Using an opioid/benzodiazepine withdrawal syndrome checklist developed from research in adult ICU patients, the Diagnostic and Statistical Manual of Mental Disorders-5, and the International Classification of Diseases, 10th Edition, we evaluated patients at baseline and for 72 hours after drug weaning was initiated. Patients received opioid/benzodiazepine (88%), opioid (10%), or benzodiazepine (2%). Probable withdrawal syndrome occurred in 44%, questionable withdrawal syndrome in 20%, and no withdrawal syndrome in 18 (36%). Signs that were more frequent in the probable withdrawal syndrome group were agitation, diarrhea, fever, tachypnea, lacrimation, and hyperactive delirium. Patients who developed probable withdrawal syndrome spent almost double the amount of time receiving mechanical ventilation, and length of stay was higher in both ICU and hospital when compared with patients in the other two groups. Age, cumulative opioid dose amounts, and previous drug (opioid/benzodiazepine, cannabis, cocaine, or heroin) use were associated with odds of developing withdrawal syndrome. With the addition of Richmond Agitation-Sedation Scale and delirium to the multilevel analysis, older age no longer had its protective effect, whereas increase in Richmond Agitation-Sedation Scale scores, delirium presence, and increased duration of mechanical ventilation were associated with higher odds of withdrawal syndrome. CONCLUSIONS: We identified probable withdrawal syndrome in a sample of trauma ICU patients through observation of several associated symptoms. Significant factors associated with withdrawal syndrome found in this study should be considered when caring for patients being weaned from opioids and/or benzodiazepines. Further validation of the opioid/benzodiazepine withdrawal syndrome checklist is recommended.

20.
Adv Skin Wound Care ; 22(8): 373-80; quiz 381-2, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19638801

RESUMO

PURPOSE: To provide the wound care practitioner with an overview of research and knowledge about the causes, mechanisms, contributing factors, and management of acute wound pain. TARGET AUDIENCE: This continuing education activity is intended for physicians and nurses with an interest in skin and wound care. OBJECTIVES: After reading this article and taking this test, the reader should be able to: 1. Describe the causes of acute wound pain. 2. Discuss research findings related to the physiology of wound pain. 3. Identify current concepts in the management of acute wound pain.


Assuntos
Dor/etiologia , Cicatrização , Ferimentos e Lesões/complicações , Doença Aguda , Humanos , Nociceptores , Manejo da Dor , Medição da Dor , Dor Pós-Operatória/etiologia , Fatores de Risco
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