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1.
Top Stroke Rehabil ; : 1-9, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38841903

RESUMO

BACKGROUND: The evaluation of gait function and severity classification of stroke patients are important to determine the rehabilitation goal and the level of exercise. Physicians often qualitatively evaluate patients' walking ability through visual gait analysis using naked eye, video images, or standardized assessment tools. Gait evaluation through observation relies on the doctor's empirical judgment, potentially introducing subjective opinions. Therefore, conducting research to establish a basis for more objective judgment is crucial. OBJECTIVE: To verify a deep learning model that classifies gait image data of stroke patients according to Functional Ambulation Category (FAC) scale. METHODS: Gait vision data from 203 stroke patients and 182 healthy individuals recruited from six medical institutions were collected to train a deep learning model for classifying gait severity in stroke patients. The recorded videos were processed using OpenPose. The dataset was randomly split into 80% for training and 20% for testing. RESULTS: The deep learning model attained a training accuracy of 0.981 and test accuracy of 0.903. Area Under the Curve(AUC) values of 0.93, 0.95, and 0.96 for discriminating among the mild, moderate, and severe stroke groups, respectively. CONCLUSION: This confirms the potential of utilizing human posture estimation based on vision data not only to develop gait parameter models but also to develop models to classify severity according to the FAC criteria used by physicians. To develop an AI-based severity classification model, a large amount and variety of data is necessary and data collected in non-standardized real environments, not in laboratories, can also be used meaningfully.

2.
J Neuroeng Rehabil ; 21(1): 42, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539223

RESUMO

BACKGROUND: Artificial intelligence is being used for rehabilitation, including monitoring exercise compliance through sensor technology. AI classification of shoulder exercise wearing an IMU sensor has only been reported in normal (i.e. painless) subjects. To prove the feasibility of monitoring exercise compliance, we aimed to classify 11 types of shoulder rehabilitation exercises using an AI (artificial intelligence) algorithm in patients with shoulder pain. We had the patients wear an IMU-based sensor, collected data during exercise, and determined the accuracy of exercise classification. METHODS: Data were collected from 58 patients (27 males, 31 females, age range 37-82 years) diagnosed with shoulder diseases such as adhesive capsulitis and rotator cuff disease. 11 types of shoulder pain rehabilitation exercise programs were developed and repeated each exercise ten times per session while wearing an IMU sensor. The study applied the Rectified Linear Unit (ReLU) and the SoftMax as the activation function for hidden layers, the output layer. RESULTS: The acquired data was used to train a DNN model using the multilayer perceptron algorithm. The trained model was used to classify 11 types of shoulder pain rehabilitation exercises. The training accuracy was 0.975 and the test accuracy was 0.925. CONCLUSION: The study demonstrates that IMU sensor data can effectively classify shoulder pain rehabilitation exercises, providing more appropriate feedback for patients. The model can be utilized to establish a system for remotely monitoring patients' exercise performance. The use of deep learning in patient monitoring and rehabilitation has significant potential to bring innovative changes to healthcare service delivery.


Assuntos
Aprendizado Profundo , Dor de Ombro , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Dor de Ombro/diagnóstico , Inteligência Artificial , Terapia por Exercício , Ombro
3.
Gait Posture ; 107: 212-217, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37863672

RESUMO

BACKGROUND: Gait assessment has been used in a wide range of clinical applications, and gait velocity is also a leading predictor of disease and physical functional aspects in older adults. RESEARCH QUESTION: The study aim to examine the changes in IMU-based gait parameters according to age in healthy adults aged 50 and older, to analyze differences between aging patients. METHODS: A total of 296 healthy adults (65.32 ± 6.74 yrs; 83.10 % female) were recruited. Gait assessment was performed using an IMU sensor-based gait analysis system, and 3D motion information of hip and knee joints was obtained using magnetic sensors. The basic characteristics of the study sample were stratified by age category, and the baseline characteristics between the groups were compared using analysis of variance (ANOVA). Pearson's correlation analysis was used to analyze the relationship between age as the dependent variable and several measures of gait parameters and joint angles as independent variables. RESULTS: The results of this study found that there were significant differences in gait velocity and both terminal double support in the three groups according to age, and statistically significant differences in the three groups in hip joint angle and knee joints angle. In addition, it was found that the gait velocity and knee/hip joint angle changed with age, and the gait velocity and knee/hip joint angle were also different in the elderly and adult groups. CONCLUSIONS: We found changes in gait parameters and joint angles according to age in healthy adults and older adults and confirmed the difference in gait velocity and joint angles between adults and older adults.


Assuntos
Análise da Marcha , Marcha , Idoso , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Estudos Transversais , Fenômenos Biomecânicos , Articulação do Joelho
4.
Cells ; 12(17)2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37681880

RESUMO

In the emerging era of cancer immunotherapy, immune checkpoint blockades (ICBs) and adoptive cell transfer therapies (ACTs) have gained significant attention. However, their therapeutic efficacies are limited due to the presence of cold type tumors, immunosuppressive tumor microenvironment, and immune-related side effects. On the other hand, dendritic cell (DC)-based vaccines have been suggested as a new cancer immunotherapy regimen that can address the limitations encountered by ICBs and ACTs. Despite the success of the first generation of DC-based vaccines, represented by the first FDA-approved DC-based therapeutic cancer vaccine Provenge, several challenges remain unsolved. Therefore, new DC vaccine strategies have been actively investigated. This review addresses the limitations of the currently most adopted classical DC vaccine and evaluates new generations of DC vaccines in detail, including biomaterial-based, immunogenic cell death-inducing, mRNA-pulsed, DC small extracellular vesicle (sEV)-based, and tumor sEV-based DC vaccines. These innovative DC vaccines are envisioned to provide a significant breakthrough in cancer immunotherapy landscape and are expected to be supported by further preclinical and clinical studies.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Vesículas Extracelulares , Humanos , Materiais Biocompatíveis , Células Dendríticas , Morte Celular Imunogênica
5.
Metabolites ; 13(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36837838

RESUMO

Biogenic amines (BAs), which are mainly generated by the microbial decarboxylation of amino acids, are important nitrogen compounds in fermented foods because of their toxicology. However, amino acids, the precursors of BAs, also play an important role in generating volatile and non-volatile metabolites, which are strongly associated with quality indicators for foods. Bacillus subtilis is one of dominant fermentative microorganism in various fermented foods and is well known as a BA-producing bacterium. In this study, B. subtilis strains which have different BAs-producing capacities, higher level of BAs production strain (BH) and lower level of BAs production strain (BL), were applied to compare the formations of volatile and non-volatile metabolite profiles according to cultivation times. In this study, histamine, putrescine, and spermidine were detected in all strains, however, 2-phenylethylamine was detected only in BH. Partial least squares discriminant analysis (PLS-DA) was applied to investigate the difference of metabolic profiles according to strains. In BH, some amino acids (phenylalanine, leucine, and threonine) and related volatile metabolites (3-methylbutanoic acid, pyrazines, styrene, and 1H-indole) were produced higher levels. On the other hand, BL produced significantly higher contents of metabolites associated with metabolism of fatty acids and nucleotides. It is necessary to consider the formation of metabolites in terms of quality as well as that of BAs during fermentation.

6.
J Neuroimaging ; 33(1): 138-146, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36168880

RESUMO

BACKGROUND AND PURPOSE: Cerebral microbleed (CMB) detection impacts disease diagnosis and management. Susceptibility-weighted imaging (SWI) MRI depictions of CMBs are used with phase images (SWIP) to distinguish blood from calcification, via qualitative intensity evaluation (bright/dark). However, the intensities depicted for a single lesion can vary within and across consecutive SWIP image planes, impairing the classification of findings as a CMB. We hypothesize that quantitative susceptibility mapping (QSM) MRI, which maps tissue susceptibility, demonstrates less in- and through-plane intensity variation, improving the clinician's ability to categorize a finding as a CMB. METHODS: Forty-eight patients with acute intracranial hemorrhage who received multi-echo gradient echo MRI used to generate both SWI/SWIP and morphology-enabled dipole inversion QSM images were enrolled. Five hundred and sixty lesions were visually classified as having homogeneous or heterogeneous in-plane and through-plane intensity by a neuroradiologist and two diagnostic radiology residents using published rating criteria. When available, brain CT scans were analyzed for calcification or acute hemorrhage. Relative risk (RR) ratios and confidence intervals (CIs) were calculated using a generalized linear model with log link and binary error. RESULTS: QSM showed unambiguous lesion signal intensity three times more frequently than SWIP (RR = 0.3235, 95% CI 0.2386-0.4386, p<.0001). The probability of QSM depicting homogeneous lesion intensity was three times greater than SWIP for small (RR = 0.3172, 95% CI 0.2382-0.4225, p<.0001), large (RR = 0.3431, 95% CI 0.2045-0.5758, p<.0001), lobar (RR = 0.3215, 95% CI 0.2151-0.4805, p<.0001), cerebellar (RR = 0.3215, 95% CI 0.2151-0.4805, p<.0001), brainstem (RR = 0.3100, 95% CI 0.1192-0.8061, p = .0163), and basal ganglia (RR = 0.3380, 95% CI 0.1980-0.5769, p<.0001) lesions. CONCLUSIONS: QSM more consistently demonstrates interpretable lesion intensity compared to SWIP as used for distinguishing CMBs from calcification.


Assuntos
Calcinose , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Hemorragias Intracranianas , Radiografia , Modelos Lineares , Calcinose/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Mapeamento Encefálico
7.
Front Physiol ; 12: 717911, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539442

RESUMO

Prohibitin 1 (PHB1) is an evolutionarily conserved and ubiquitously expressed protein that stabilizes mitochondrial chaperone. Our previous studies showed that liver-specific Phb1 deficiency induced liver injuries and aggravated lipopolysaccharide (LPS)-induced innate immune responses. In this study, we performed RNA-sequencing (RNA-seq) analysis with liver tissues to investigate global gene expression among liver-specific Phb1-/-, Phb1+/-, and WT mice, focusing on the differentially expressed (DE) genes between Phb1+/- and WT. When 78 DE genes were analyzed for biological functions, using ingenuity pathway analysis (IPA) tool, lipid metabolism-related genes, including insulin receptor (Insr), sterol regulatory element-binding transcription factor 1 (Srebf1), Srebf2, and SREBP cleavage-activating protein (Scap) appeared to be downregulated in liver-specific Phb1+/- compared with WT. Diseases and biofunctions analyses conducted by IPA verified that hepatic system diseases, including liver fibrosis, liver hyperplasia/hyperproliferation, and liver necrosis/cell death, which may be caused by hepatotoxicity, were highly associated with liver-specific Phb1 deficiency in mice. Interestingly, of liver disease-related 5 DE genes between Phb1+/- and WT, the mRNA expressions of forkhead box M1 (Foxm1) and TIMP inhibitor of metalloproteinase (Timp1) were matched with validation for RNA-seq in liver tissues and AML12 cells transfected with Phb1 siRNA. The results in this study provide additional insights into molecular mechanisms responsible for increasing susceptibility of liver injuries associated with hepatic Phb1.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34360095

RESUMO

The aim of this study was to examine whether a Simulation-based Empathy Enhancement program for Caregivers of the Elderly (SEE-C) was effective in increasing program satisfaction and positive emotional changes of older adults. A total of 100 older adults living alone were randomly assigned to experimental and control groups. The experimental group was interviewed by caregivers who experienced SEE-C while the control group was interviewed by caregivers who did not experience SEE-C. In both elderly groups, post session satisfaction and affective state were assessed using a Session Evaluation Questionnaire (SEQ). Chi-square test and Mann-Whitney U test were conducted. The experimental group (n = 49) reported significantly higher scores than the control group (n = 51) for all three categories of SEQ: session-depth (Mann-Whitney U = 1651.5, p = 0.005), session-smoothness (Mann-Whitney U = 1803.0, p = 0.000), and emotion-positivity (Mann-Whitney U = 1783.0, p = 0.000). However, the experimental group had significantly lower scores for the arousal category of SEQ (Mann-Whitney U = 873.5, p = 0.009). SEE-C could have a positive impact on interviews for elderly care in terms of raising the satisfaction of the interviewee.


Assuntos
Cuidadores , Empatia , Idoso , Humanos , Satisfação Pessoal , Inquéritos e Questionários
9.
J Magn Reson Imaging ; 51(3): 734-747, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31294898

RESUMO

BACKGROUND: To maintain cerebral blood flow (CBF), cerebral blood vessels dilate and contract in response to blood supply through cerebrovascular reactivity (CR). PURPOSE: Cardiovascular (CV) disease is associated with increased stroke risk, but which risk factors specifically impact CR is unknown. STUDY TYPE: Prospective longitudinal. SUBJECTS: Fifty-three subjects undergoing carotid endarterectomy or stenting. FIELD STRENGTH/SEQUENCE: 3T, 3D pseudo-continuous arterial spin labeling (PCASL) ASL, and T1 3D fast spoiled gradient echo (FSPGR). ASSESSMENT: We evaluated group differences in CBF changes for multiple cardiovascular risk factors in patients undergoing carotid revascularization surgery. STATISTICAL TESTS: PRE (baseline), POST (48-hour postop), and 6MO (6 months postop) whole-brain CBF measurements, as 129 CBF maps from 53 subjects were modeled as within-subject analysis of variance (ANOVA). To identify CV risk factors associated with CBF change, the CBF change from PRE to POST, POST to 6MO, and PRE to 6MO were modeled as multiple linear regression with each CV risk factor as an independent variable. Statistical models were performed controlling for age on a voxel-by-voxel basis using SPM8. Significant clusters were reported if familywise error (FWE)-corrected cluster-level was P < 0.05, while the voxel-level significance threshold was set for P < 0.001. RESULTS: The entire group showed significant (cluster-level P < 0.001) CBF increase from PRE to POST, decrease from POST to 6MO, and no significant difference (all voxels with P > 0.001) from PRE to 6MO. Of multiple CV risk factors evaluated, only elevated systolic blood pressure (SBP, P = 0.001), chronic renal insufficiency (CRI, P = 0.026), and history of prior stroke (CVA, P < 0.001) predicted lower increases in CBF PRE to POST. Over POST to 6MO, obesity predicted lower (P > 0.001) and cholesterol greater CBF decrease (P > 0.001). DATA CONCLUSION: The CV risk factors of higher SBP, CRI, CVA, BMI, and cholesterol may indicate altered CR, and may warrant different stroke risk mitigation and special consideration for CBF change evaluation. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2020;51:734-747.


Assuntos
Doenças Cardiovasculares , Encéfalo , Doenças Cardiovasculares/diagnóstico por imagem , Circulação Cerebrovascular , Fatores de Risco de Doenças Cardíacas , Humanos , Imageamento por Ressonância Magnética , Estudos Prospectivos , Fatores de Risco , Marcadores de Spin
10.
Korean J Food Sci Anim Resour ; 37(5): 716-725, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29147095

RESUMO

The objective of this study was to determine the relationship between composition of muscle fiber types and meat quality traits of eight major muscles from Hanwoo steers. Longissimus lumborum (LL), psoas major (PM), semimembranosus (SM), semitendinosus (ST), gluteus medius (GM), triceps brachii (TB), rectus abdominis (RA) and superficialis flexor (SF) muscles were obtained from 9 Hanwoo steers and subjected to histochemical analysis. There were significant (p<0.05) differences in fiber number percentage (FNP) and fiber area percentage (FAP) of fiber types among these 8 major muscles. SF had the highest FNP of type I (55.9%), followed by PM (46.4%), TB (45.4%), RA (38.5%), LD (36.8%), GM (36.0%), SM (22.2%), and ST (18.8%). FAP of type IIB ranged from 9.9% in SF to 58.7% in ST. Meat quality traits, including fat content, myoglobin content, collagen content, CIE L* and a*, drip and cooking loss, sarcomere length and Warner-Bratzler shear force, were all significantly (p<0.05) different among these muscles. Due to such diversities among these 8 muscles, lack of correlations were found between fiber type composition and meat quality traits. These results suggest that correlation for each individual muscle should be used to improve meat quality and profitability of retail beef cuts.

11.
Korean J Food Sci Anim Resour ; 37(4): 593-598, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28943772

RESUMO

The objective of this study was to determine the influence of quality grade (QG) on meat tenderness characteristics of ten major muscles from Hanwoo steers. A total of 25 Hanwoo carcasses (5 carcasses × 5 QGs) were selected. Intramuscular fat content, collagen content, sarcomere length, and Warner-Bratzler shear force (WBSF) of Longissimus thoracis (LT), Longissimus lumborum (LL), Psoas major (PM), Semisponals (SS), Triceps brachii (TB), Semimembranosus (SM), Gluteus medius (GM), Rectus Abdominis (RA), Superficialis flexor (SF), and Internal and external intercostal (IC) were determined. IC had the highest fat content, followed by LT, RA, LL, PM, GM, SS, SF, TB, and SM. High-fat muscles such as LT, LL, IC, RA, and PM had significantly (p<0.05) different fat contents among QGs. Collagen contents were significantly (p<0.05) different among QGs. With decreasing QG, increasing collagen content was found in muscles. There were significant (p<0.05) differences in sarcomere length among QGs of several muscles. However, no significant (p>0.05) difference in sarcomere length was found among QGs for LL, PM, or RA muscle. PM had the lowest WBSF, followed by LL, LT, RA, IC, GM, SM, SF, SS, and TB. WBSF of QG 1++ was lower than that of QG 1 for SS, TB, and SM. All muscles of QG 1 showed lower WBSF than QG 3 except TB or IC. Results of this study suggested that differences in WBSF among these 10 muscles by QG were due to differences in collagen content and sarcomere length.

12.
Int J Pediatr Otorhinolaryngol ; 90: 113-118, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27729115

RESUMO

INTRODUCTION: Surgical simulators are designed to improve operative skills and patient safety. Transcanal Endoscopic Ear Surgery (TEES) is a relatively new surgical approach with a slow learning curve due to one-handed dissection. A reusable and customizable 3-dimensional (3D)-printed endoscopic ear surgery simulator may facilitate the development of surgical skills with high fidelity and low cost. Herein, we aim to design, fabricate, and test a low-cost and reusable 3D-printed TEES simulator. METHODS: The TEES simulator was designed in computer-aided design (CAD) software using anatomic measurements taken from anthropometric studies. Cross sections from external auditory canal samples were traced as vectors and serially combined into a mesh construct. A modified tympanic cavity with a modular testing platform for simulator tasks was incorporated. Components were fabricated using calcium sulfate hemihydrate powder and multiple colored infiltrants via a commercial inkjet 3D-printing service. RESULTS: All components of a left-sided ear were printed to scale. Six right-handed trainees completed three trials each. Mean trial time (n = 3) ranged from 23.03 to 62.77 s using the dominant hand for all dissection. Statistically significant differences between first and last completion time with the dominant hand (p < 0.05) and average completion time for junior and senior residents (p < 0.05) suggest construct validity. CONCLUSIONS: A 3D-printed simulator is feasible for TEES simulation. Otolaryngology training programs with access to a 3D printer may readily fabricate a TEES simulator, resulting in inexpensive yet high-fidelity surgical simulation.


Assuntos
Orelha Média/cirurgia , Endoscopia/educação , Modelos Anatômicos , Procedimentos Cirúrgicos Otológicos/educação , Impressão Tridimensional , Treinamento por Simulação/métodos , Desenho Assistido por Computador , Dissecação/educação , Meato Acústico Externo/anatomia & histologia , Orelha Média/anatomia & histologia , Humanos , Pediatria/educação
13.
Neurosci Biobehav Rev ; 51: 164-88, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25625874

RESUMO

The role of serotonin in depression and antidepressant treatment remains unresolved despite decades of research. In this paper, we make three major claims. First, serotonin transmission is elevated in multiple depressive phenotypes, including melancholia, a subtype associated with sustained cognition. The primary challenge to this first claim is that the direct pharmacological effect of most symptom-reducing medications, such as the selective serotonin reuptake inhibitors (SSRIs), is to increase synaptic serotonin. The second claim, which is crucial to resolving this paradox, is that the serotonergic system evolved to regulate energy. By increasing extracellular serotonin, SSRIs disrupt energy homeostasis and often worsen symptoms during acute treatment. Our third claim is that symptom reduction is not achieved by the direct pharmacological properties of SSRIs, but by the brain's compensatory responses that attempt to restore energy homeostasis. These responses take several weeks to develop, which explains why SSRIs have a therapeutic delay. We demonstrate the utility of our claims by examining what happens in animal models of melancholia and during acute and chronic SSRI treatment.


Assuntos
Antidepressivos/farmacologia , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Serotonina/metabolismo , Animais , Antidepressivos/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico
14.
Mol Cell Biol ; 34(7): 1280-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24469401

RESUMO

Impairment of astrocytic glutamate transporter (GLT-1; EAAT2) function is associated with multiple neurodegenerative diseases, including Parkinson's disease (PD) and manganism, the latter being induced by chronic exposure to high levels of manganese (Mn). Mn decreases EAAT2 promoter activity and mRNA and protein levels, but the molecular mechanism of Mn-induced EAAT2 repression at the transcriptional level has yet to be elucidated. We reveal that transcription factor Yin Yang 1 (YY1) is critical in repressing EAAT2 and mediates the effects of negative regulators, such as Mn and tumor necrosis factor alpha (TNF-α), on EAAT2. YY1 overexpression in astrocytes reduced EAAT2 promoter activity, while YY1 knockdown or mutation of the YY1 consensus site of the EAAT2 promoter increased its promoter activity and attenuated the Mn-induced repression of EAAT2. Mn increased YY1 promoter activity and mRNA and protein levels via NF-κB activation. This led to increased YY1 binding to the EAAT2 promoter region. Epigenetically, histone deacetylase (HDAC) classes I and II served as corepressors of YY1, and, accordingly, HDAC inhibitors increased EAAT2 promoter activity and reversed the Mn-induced repression of EAAT2 promoter activity. Taken together, our findings suggest that YY1, with HDACs as corepressors, is a critical negative transcriptional regulator of EAAT2 and mediates Mn-induced EAAT2 repression.


Assuntos
Astrócitos/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Células Cultivadas , Epigênese Genética , Transportador 2 de Aminoácido Excitatório/genética , Técnicas de Silenciamento de Genes , Histona Desacetilases/metabolismo , Manganês/metabolismo , Modelos Biológicos , Mutação , NF-kappa B/metabolismo , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Proteínas Repressoras/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Transcrição YY1/antagonistas & inibidores , Fator de Transcrição YY1/genética
15.
J Biol Chem ; 288(40): 28975-86, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-23955341

RESUMO

Tamoxifen (TX), a selective estrogen receptor modulator, exerts antagonistic effects on breast tissue and is used to treat breast cancer. Recent evidence also suggests that it may act as an agonist in brain tissue. We reported previously that TX enhanced the expression and function of glutamate transporter 1 (GLT-1) in rat astrocytes, an effect that was mediated by TGF-α. To gain further insight into the mechanisms that mediate TX-induced up-regulation of GLT-1 (EAAT2 in humans), we investigated its effect on GLT-1 at the transcriptional level. TX phosphorylated the cAMP response element-binding protein (CREB) and recruited CREB to the GLT-1 promoter consensus site. The effect of TX on astrocytic GLT-1 was attenuated by the inhibition of PKA, the upstream activator of the CREB pathway. In addition, the effect of TX on GLT-1 promoter activity was abolished by the inhibition of the NF-κB pathway. Furthermore, TX recruited the NF-κB subunits p65 and p50 to the NF-κB binding domain of the GLT-1 promoter. Mutation of NF-κB (triple, -583/-282/-251) or CRE (-308) sites on the GLT-1 promoter led to significant repression of the promoter activity, but neither mutant completely abolished the TX-induced GLT-1 promoter activity. Mutation of both the NF-κB (-583/-282/-251) and CRE (-308) sites led to a complete abrogation of the effect of TX on GLT-1 promoter activity. Taken together, our findings establish that TX regulates GLT-1 via the CREB and NF-κB pathways.


Assuntos
Astrócitos/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Transportador 2 de Aminoácido Excitatório/genética , NF-kappa B/metabolismo , Tamoxifeno/farmacologia , Regulação para Cima/efeitos dos fármacos , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/enzimologia , Sítios de Ligação , Extratos Celulares , Células Cultivadas , Imunoprecipitação da Cromatina , Transportador 2 de Aminoácido Excitatório/metabolismo , Humanos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Elementos de Resposta/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Crescimento Transformador alfa/metabolismo , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/metabolismo
16.
J Biol Chem ; 287(32): 26817-28, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22645130

RESUMO

The G protein-coupled estrogen receptor GPR30 contributes to the neuroprotective effects of 17ß-estradiol (E2); however, the mechanisms associated with this protection have yet to be elucidated. Given that E2 increases astrocytic expression of glutamate transporter-1 (GLT-1), which would prevent excitotoxic-induced neuronal death, we proposed that GPR30 mediates E2 action on GLT-1 expression. To investigate this hypothesis, we examined the effects of G1, a selective agonist of GPR30, and GPR30 siRNA on astrocytic GLT-1 expression, as well as glutamate uptake in rat primary astrocytes, and explored potential signaling pathways linking GPR30 to GLT-1. G1 increased GLT-1 protein and mRNA levels, subject to regulation by both MAPK and PI3K signaling. Inhibition of TGF-α receptor suppressed the G1-induced increase in GLT-1 expression. Silencing GPR30 reduced the expression of both GLT-1 and TGF-α and abrogated the G1-induced increase in GLT-1 expression. Moreover, the G1-induced increase in GLT-1 protein expression was abolished by a protein kinase A inhibitor and an NF-κB inhibitor. G1 also enhanced cAMP response element-binding protein (CREB), as well as both NF-κB p50 and NF-κB p65 binding to the GLT-1 promoter. Finally, to model dysfunction of glutamate transporters, manganese was used, and G1 was found to attenuate manganese-induced impairment in GLT-1 protein expression and glutamate uptake. Taken together, the present data demonstrate that activation of GPR30 increases GLT-1 expression via multiple pathways, suggesting that GPR30 is worthwhile as a potential target to be explored for developing therapeutics of excitotoxic neuronal injury.


Assuntos
Astrócitos/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Receptores Acoplados a Proteínas G/fisiologia , Animais , Sequência de Bases , Western Blotting , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Primers do DNA , Inativação Gênica , Imuno-Histoquímica , Reação em Cadeia da Polimerase , Proteínas Quinases/metabolismo , RNA Interferente Pequeno , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/genética
17.
Alcohol ; 45(5): 499-505, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21549549

RESUMO

Alcohol consumption has been known to be related to the prevalence of metabolic syndrome (MS). Although some studies have revealed that mild to moderate alcohol consumption reduces the risk of MS, most of these studies have focused the effect of alcohol consumption amount on MS. We examined the association between alcohol-drinking patterns and MS by using the alcohol use disorders identification test (AUDIT) questionnaire to study 1,768 alcohol drinkers (847 men, 921 women) aged 20-75 years from Korean National Health and Nutrition Examination Survey in 2007. When compared with the subjects in the reference group (AUDIT score ≤ 7), the odds ratios (ORs, 95% confidence intervals [CIs]) for MS of subjects in the highest group (AUDIT score ≥ 16) were 3.92 (2.40-6.22) in men and 2.27 (0.87-5.89) in women after adjusting for confounding variables. Among the items of the AUDIT score, several alcohol-drinking patterns, including "drinking frequency," "usual drinking quantity," "frequency of high-risk drinking," "frequency of inability to stop drinking," "frequency of feeling guilty after drinking," and "frequency of inability to remember after drinking" were strongly associated with the prevalence of MS in men. In women, there were significant relationships between MS and "usual drinking quantity," "frequency of feeling guilty after drinking," and "frequency of inability to stop drinking." In summary, AUDIT score was strongly associated with MS in Korean adults, particularly in men. Accordingly, in addition to the amount of daily alcohol consumption, alcohol-drinking patterns should be addressed in the prevention and treatment of MS.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Alcoolismo/epidemiologia , Síndrome Metabólica/epidemiologia , Adulto , Povo Asiático , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Razão de Chances , Prevalência , República da Coreia/epidemiologia , Fatores de Risco , Inquéritos e Questionários
18.
Stem Cells Dev ; 19(4): 557-68, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19642865

RESUMO

Studies revealed that PI3K/AKT/mTOR signaling is important in the regulation of human embryonic stem cell (hESC) self-renewal and differentiation. However, its action on osteogenic differentiation of hESCs is poorly understood. We tested the effects of pharmacological PI3K/AKT/mTOR inhibitors on their potential to induce osteogenic differentiation of hESCs. Under feeder-free culture conditions, rapamycin (an mTOR inhibitor) potently inhibited the activities of mTOR and p70S6K in undifferentiated hESCs; however, LY294002 (a PI3K inhibitor) and an AKT inhibitor had no effects. Treatment with any of these inhibitors down-regulated the hESC markers Oct4 and Nanog, but only rapamycin induced the up-regulation of the early osteogenic markers BMP2 and Runx2. We also observed that hESCs differentiated when treated with FK506, a structural analog of rapamycin, but did not exhibit an osteogenic phenotype. Increases in Smad1/5/8 phosphorylation and Id1-4 mRNA expression indicated that rapamycin significantly stimulated BMP/Smad signaling. After inducing both hESCs and human embryoid bodies (hEBs) for 2-3 weeks with rapamycin, osteoblastic differentiation was further characterized by the expression of osteoblastic marker mRNAs and/or proteins (osterix, osteocalcin, osteoprotegerin, osteonectin, and bone sialoprotein), alkaline phosphatase activity, and alizarin red S staining for mineralized bone nodule formation. No significant differences in the osteogenic phenotypes of rapamycin-differentiated hESCs and hEBs were detected. Our results suggest that, among these 3 inhibitors, only rapamycin functions as a potent stimulator of osteoblastic differentiation of hESCs, and it does so by modulating rapamycin-sensitive mTOR and BMP/Smad signaling.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Osteoblastos , Osteogênese , Sirolimo/farmacologia , Biomarcadores , Receptores de Proteínas Morfogenéticas Ósseas/genética , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Linhagem Celular , Cromonas/farmacologia , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Inibidores Enzimáticos/farmacologia , Proteínas de Homeodomínio/genética , Humanos , Imunossupressores/farmacologia , Proteína 1 Inibidora de Diferenciação/genética , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Morfolinas/farmacologia , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/genética , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Serina-Treonina Quinases TOR , Tacrolimo/farmacologia
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