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1.
J Otolaryngol Head Neck Surg ; 53: 19160216241250350, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38888936

RESUMO

BACKGROUND: Diagnostic dilemma between clinical Meniere's disease and radiological endolymphatic hydrops (EH) has emerged since the introduction of hydrops magnetic resonance imaging (MRI). The aim of this study is to explore the potential application of hydrops MRI on diagnosing the EH. METHODS: This review was developed from peer-reviewed articles published in those journals listed on journal of citation reports. The MEDLINE database of the US National Library of Medicine, Scopus, and Google Scholar were used to collect articles based on the guidelines (PRISMA 2020 statement) for reporting reviews. RESULTS: Initially, 470 articles were retrieved from 1983 to 2023, and 80 relevant articles were ultimately selected. The sensitivity (69%-92%) and specificity (78%-96%) values varied from each laboratory for detecting EH via hydrops MRI, probably due to candidate selection and the grading system employed. CONCLUSION: The application of hydrops MRI allows (1) differentiation between EH and sudden sensorineural hearing loss; (2) determination of the affected side of EH; and (3) confirmation of the diagnosis of EH concomitant with other disorders. Notably, not all differentials for EH can be visualized on MR images. One of the existing gaps to be filled is that updated hydrops MRI fails to identify distortion, that is, rupture, collapse, fistula, or fibrosis of the inner ear compartments, akin to what histopathological evidence can demonstrate. Hence, enhanced ultrahigh resolution of hydrops MRI is required for demonstrating fine structures of the inner ear compartments in the future.


Assuntos
Hidropisia Endolinfática , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Hidropisia Endolinfática/diagnóstico por imagem , Hidropisia Endolinfática/diagnóstico , Doença de Meniere/diagnóstico por imagem , Doença de Meniere/diagnóstico , Diagnóstico Diferencial , Sensibilidade e Especificidade
2.
J Formos Med Assoc ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38906730

RESUMO

BACKGROUND: Both vestibular schwannoma (VS) and Meniere's disease (MD) patients underwent hydrops MRI to clarify the relationship between VS and endolymphatic hydrops (EH). METHODS: Eighty patients with VS or MD underwent an inner ear test battery followed by hydrops MRI, and were then divided into 3 groups. Group A comprised 58 MD patients (62 ears) with positive EH but negative VS. Group B included 18 VS patients (18 ears) with negative EH, while Group C consisted of 4 patients (4 ears) who had VS concomitant with EH. Another 14 MD patients who tested negative for EH on hydrops MRI were initially excluded from this cohort, but were later included for comparison. RESULTS: The decreasing prevalence of EH at the cochlea, saccule and utricle in Group A was identified in 59 (95%), 42 (68%) and 40 (65%) ears, respectively, mimicking a declining sequence of abnormality rates running from audiometry (86%), cervical vestibular-evoked myogenic potential (cVEMP) test (55%) to the ocular (oVEMP) test (53%). However, such decreasing trend was not identified in Groups B and C. In Groups C and A combined, 4 (6%) of 62 EH patients had concomitant VS. Conversely, 4 (18%) of 22 VS patients in Groups C and B combined had concurrent EH. CONCLUSION: A very low (6%) rate of VS in EH patients indicates that VS in EH patients may be coincidental. In contrast, EH was identified in 18% prevalence of VS patients, mirroring the 22% prevalence of cochlear EH demonstrated in VS donors through histopathological studies.

3.
Epilepsia ; 65(1): 46-56, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37347512

RESUMO

OBJECTIVES: Although hemispheric surgeries are among the most effective procedures for drug-resistant epilepsy (DRE) in the pediatric population, there is a large variability in seizure outcomes at the group level. A recently developed HOPS score provides individualized estimation of likelihood of seizure freedom to complement clinical judgement. The objective of this study was to develop a freely accessible online calculator that accurately predicts the probability of seizure freedom for any patient at 1-, 2-, and 5-years post-hemispherectomy. METHODS: Retrospective data of all pediatric patients with DRE and seizure outcome data from the original Hemispherectomy Outcome Prediction Scale (HOPS) study were included. The primary outcome of interest was time-to-seizure recurrence. A multivariate Cox proportional-hazards regression model was developed to predict the likelihood of post-hemispheric surgery seizure freedom at three time points (1-, 2- and 5- years) based on a combination of variables identified by clinical judgment and inferential statistics predictive of the primary outcome. The final model from this study was encoded in a publicly accessible online calculator on the International Network for Epilepsy Surgery and Treatment (iNEST) website (https://hops-calculator.com/). RESULTS: The selected variables for inclusion in the final model included the five original HOPS variables (age at seizure onset, etiologic substrate, seizure semiology, prior non-hemispheric resective surgery, and contralateral fluorodeoxyglucose-positron emission tomography [FDG-PET] hypometabolism) and three additional variables (age at surgery, history of infantile spasms, and magnetic resonance imaging [MRI] lesion). Predictors of shorter time-to-seizure recurrence included younger age at seizure onset, prior resective surgery, generalized seizure semiology, FDG-PET hypometabolism contralateral to the side of surgery, contralateral MRI lesion, non-lesional MRI, non-stroke etiologies, and a history of infantile spasms. The area under the curve (AUC) of the final model was 73.0%. SIGNIFICANCE: Online calculators are useful, cost-free tools that can assist physicians in risk estimation and inform joint decision-making processes with patients and families, potentially leading to greater satisfaction. Although the HOPS data was validated in the original analysis, the authors encourage external validation of this new calculator.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Hemisferectomia , Espasmos Infantis , Criança , Humanos , Hemisferectomia/métodos , Espasmos Infantis/cirurgia , Estudos Retrospectivos , Fluordesoxiglucose F18 , Resultado do Tratamento , Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Convulsões/diagnóstico , Convulsões/etiologia , Convulsões/cirurgia , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia Resistente a Medicamentos/cirurgia , Imageamento por Ressonância Magnética , Eletroencefalografia
5.
Eur Arch Otorhinolaryngol ; 280(5): 2209-2216, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36316577

RESUMO

PURPOSE: This study adopted the cervical and ocular vestibular-evoked myogenic potential (cVEMP and oVEMP) tests in Meniere's disease (MD) patients to correlate them with vestibular endolymphatic hydrops (EH) on MR images. METHODS: A total of 25 patients with unilateral definite MD identified by positive cochlear hydrops on MR images were enrolled. All patients underwent audiometry, cVEMP test and oVEMP test, followed by MR imaging for confirmation. RESULTS: A significantly declining sequence of abnormality rates in MD patients was identified from the audiometry (92%), cVEMP test (52%) to the oVEMP test (40%), which was consistent with a significantly decreasing order of prevalence of EH on MR images running from the cochlea (100%), saccule (56%) to the utricle (52%). The cVEMP test for detecting the saccular hydrops revealed a sensitivity of 62%, while the oVEMP test for assessing the utricular hydrops showed a sensitivity of 70%. However, correlating VEMP results with vestibular hydrops did not show any significant relationship. In addition, mean hearing level (MHL) at four frequencies (500, 1000, 2000, and 3000 Hz) of Grade I cochlear hydrops (51 ± 19 dB) did not significantly differ from Grade II cochlear hydrops (53 ± 19 dB). CONCLUSION: Limitations of the updated MR imaging for visualizing the hydrops comprised: (1) failure to correlate vestibular hydrops with VEMP results, and (2) failure to correlate grade of cochlear hydrops with MHL. The reason is probably because updated MR imaging fails to identify distorted contour of the cochlea/utricle/saccule. Further advanced technique using ultrahigh resolution of fine structures in the inner ear compartments is essential to promote a wider use of MR imaging.


Assuntos
Imageamento por Ressonância Magnética , Doença de Meniere , Humanos , Potenciais Evocados Miogênicos Vestibulares , Doença de Meniere/diagnóstico , Doença de Meniere/diagnóstico por imagem , Hidropisia Endolinfática/diagnóstico por imagem , Audiometria , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso
6.
Life (Basel) ; 11(12)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34947936

RESUMO

Telomeres cap the ends of eukaryotic chromosomes and are indispensable chromatin structures for genome protection and replication. Telomere length maintenance has been attributed to several functional modulators, including telomerase, the shelterin complex, and the CST complex, synergizing with DNA replication, repair, and the RNA metabolism pathway components. As dysfunctional telomere maintenance and telomerase activation are associated with several human diseases, including cancer, the molecular mechanisms behind telomere length regulation and protection need particular emphasis. Cancer cells exhibit telomerase activation, enabling replicative immortality. Telomerase reverse transcriptase (TERT) activation is involved in cancer development through diverse activities other than mediating telomere elongation. This review describes the telomere functions, the role of functional modulators, the implications in cancer development, and the future therapeutic opportunities.

7.
Epilepsia ; 62(11): 2707-2718, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34510448

RESUMO

OBJECTIVE: This study was undertaken to determine whether the vertical parasagittal approach or the lateral peri-insular/peri-Sylvian approach to hemispheric surgery is the superior technique in achieving long-term seizure freedom. METHODS: We conducted a post hoc subgroup analysis of the HOPS (Hemispheric Surgery Outcome Prediction Scale) study, an international, multicenter, retrospective cohort study that identified predictors of seizure freedom through logistic regression modeling. Only patients undergoing vertical parasagittal, lateral peri-insular/peri-Sylvian, or lateral trans-Sylvian hemispherotomy were included in this post hoc analysis. Differences in seizure freedom rates were assessed using a time-to-event method and calculated using the Kaplan-Meier survival method. RESULTS: Data for 672 participants across 23 centers were collected on the specific hemispherotomy approach. Of these, 72 (10.7%) underwent vertical parasagittal hemispherotomy and 600 (89.3%) underwent lateral peri-insular/peri-Sylvian or trans-Sylvian hemispherotomy. Seizure freedom was obtained in 62.4% (95% confidence interval [CI] = 53.5%-70.2%) of the entire cohort at 10-year follow-up. Seizure freedom was 88.8% (95% CI = 78.9%-94.3%) at 1-year follow-up and persisted at 85.5% (95% CI = 74.7%-92.0%) across 5- and 10-year follow-up in the vertical subgroup. In contrast, seizure freedom decreased from 89.2% (95% CI = 86.3%-91.5%) at 1-year to 72.1% (95% CI = 66.9%-76.7%) at 5-year to 57.2% (95% CI = 46.6%-66.4%) at 10-year follow-up for the lateral subgroup. Log-rank test found that vertical hemispherotomy was associated with durable seizure-free progression compared to the lateral approach (p = .01). Patients undergoing the lateral hemispherotomy technique had a shorter time-to-seizure recurrence (hazard ratio = 2.56, 95% CI = 1.08-6.04, p = .03) and increased seizure recurrence odds (odds ratio = 3.67, 95% CI = 1.05-12.86, p = .04) compared to those undergoing the vertical hemispherotomy technique. SIGNIFICANCE: This pilot study demonstrated more durable seizure freedom of the vertical technique compared to lateral hemispherotomy techniques. Further studies, such as prospective expertise-based observational studies or a randomized clinical trial, are required to determine whether a vertical approach to hemispheric surgery provides superior long-term seizure outcomes.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Hemisferectomia , Criança , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia/cirurgia , Hemisferectomia/métodos , Humanos , Projetos Piloto , Estudos Prospectivos , Estudos Retrospectivos , Convulsões/cirurgia , Resultado do Tratamento
8.
Int J Mol Sci ; 22(7)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807403

RESUMO

Platelets play a crucial role in the physiology of primary hemostasis and pathological processes such as arterial thrombosis; thus, developing a therapeutic target that prevents platelet activation can reduce arterial thrombosis. Pterostilbene (PTE) has remarkable pharmacological activities, including anticancer and neuroprotection. Few studies have reported the effects of pterostilbene on platelet activation. Thus, we examined the inhibitory mechanisms of pterostilbene in human platelets and its role in vascular thrombosis prevention in mice. At low concentrations (2-8 µM), pterostilbene strongly inhibited collagen-induced platelet aggregation. Furthermore, pterostilbene markedly diminished Lyn, Fyn, and Syk phosphorylation and hydroxyl radical formation stimulated by collagen. Moreover, PTE directly hindered integrin αIIbß3 activation through interfering with PAC-1 binding stimulated by collagen. In addition, pterostilbene affected integrin αIIbß3-mediated outside-in signaling, such as integrin ß3, Src, and FAK phosphorylation, and reduced the number of adherent platelets and the single platelet spreading area on immobilized fibrinogen as well as thrombin-stimulated fibrin clot retraction. Furthermore, pterostilbene substantially prolonged the occlusion time of thrombotic platelet plug formation in mice. This study demonstrated that pterostilbene exhibits a strong activity against platelet activation through the inhibition of integrin αIIbß3-mediated inside-out and outside-in signaling, suggesting that pterostilbene can serve as a therapeutic agent for thromboembolic disorders.


Assuntos
Plaquetas/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/efeitos dos fármacos , Estilbenos/metabolismo , Animais , Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Retração do Coágulo/efeitos dos fármacos , Colágeno , Fibrinogênio/metabolismo , Hemostasia/efeitos dos fármacos , Humanos , Integrina alfa2/efeitos dos fármacos , Integrina alfa2/metabolismo , Integrina beta3/efeitos dos fármacos , Integrina beta3/metabolismo , Integrinas/efeitos dos fármacos , Integrinas/metabolismo , Camundongos , Selectina-P/metabolismo , Fosforilação , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Trombose/metabolismo
9.
Aging Cell ; 20(5): e13340, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33783931

RESUMO

Amyloid-beta (Aß) oligomer is known to contribute to the pathophysiology of age-related macular degeneration. Herein, we aimed to elucidate the in vivo and in vitro effects of Aß1-42 application on retinal morphology in rats. Our in vivo studies revealed that intracerebroventricular administration of Aß1-42 oligomer caused dysmorphological changes in both retinal ganglion cells and retinal pigment epithelium. In addition, in vitro studies revealed that ARPE-19 cells following Aß1-42 oligomer application had decreased viability along with apoptosis and decreased expression of the tight junction proteins, increased expression of both phosphor-AKT and phosphor-GSK3ß and decreased expression of both SIRT1 and ß-catenin. Application of conditioned medium (CM) obtained from mesenchymal stem cells (MSC) protected against Aß1-42 oligomer-induced retinal pathology in both rats and ARPE-19 cells. In order to explore the potential role of peptides secreted from the MSCs, we applied mass spectrometry to compare the peptidomics profiles of the MSC-CM. Gene ontology enrichment analysis and String analysis were performed to explore the differentially expressed peptides by predicting the functions of their precursor proteins. Bioinformatics analysis showed that 3-8 out of 155-163 proteins in the MSC-CM maybe associated with SIRT1/pAKT/pGSK3ß/ß-catenin, tight junction proteins, and apoptosis pathway. In particular, the secretomes information on the MSC-CM may be helpful for the prevention and treatment of retinal pathology in age-related macular degeneration.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Células-Tronco Mesenquimais/metabolismo , Retina/patologia , Doença de Alzheimer/induzido quimicamente , Peptídeos beta-Amiloides , Animais , Apoptose , Hipóxia Celular , Linhagem Celular , Meios de Cultivo Condicionados , Modelos Animais de Doenças , Humanos , Aprendizagem , Fragmentos de Peptídeos , Ratos , Degeneração Retiniana/patologia , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Transdução de Sinais , Memória Espacial , Proteínas de Junções Íntimas/metabolismo , beta Catenina/metabolismo
10.
Epilepsia ; 62(5): 1064-1073, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33713438

RESUMO

OBJECTIVE: To develop and validate a model to predict seizure freedom in children undergoing cerebral hemispheric surgery for the treatment of drug-resistant epilepsy. METHODS: We analyzed 1267 hemispheric surgeries performed in pediatric participants across 32 centers and 12 countries to identify predictors of seizure freedom at 3 months after surgery. A multivariate logistic regression model was developed based on 70% of the dataset (training set) and validated on 30% of the dataset (validation set). Missing data were handled using multiple imputation techniques. RESULTS: Overall, 817 of 1237 (66%) hemispheric surgeries led to seizure freedom (median follow-up = 24 months), and 1050 of 1237 (85%) were seizure-free at 12 months after surgery. A simple regression model containing age at seizure onset, presence of generalized seizure semiology, presence of contralateral 18-fluoro-2-deoxyglucose-positron emission tomography hypometabolism, etiologic substrate, and previous nonhemispheric resective surgery is predictive of seizure freedom (area under the curve = .72). A Hemispheric Surgery Outcome Prediction Scale (HOPS) score was devised that can be used to predict seizure freedom. SIGNIFICANCE: Children most likely to benefit from hemispheric surgery can be selected and counseled through the implementation of a scale derived from a multiple regression model. Importantly, children who are unlikely to experience seizure control can be spared from the complications and deficits associated with this surgery. The HOPS score is likely to help physicians in clinical decision-making.


Assuntos
Epilepsia Resistente a Medicamentos/cirurgia , Hemisferectomia , Resultado do Tratamento , Idade de Início , Criança , Pré-Escolar , Estudos de Coortes , Epilepsia Resistente a Medicamentos/patologia , Epilepsia Resistente a Medicamentos/fisiopatologia , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Prognóstico , Estudos Retrospectivos , Fatores de Risco
11.
Int J Mol Sci ; 23(1)2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-35008520

RESUMO

Studies have discovered that different extracts of Evodia rutaecarpa and its phytochemicals show a variety of biological activities associated with inflammation. Although rutaecarpine, an alkaloid isolated from the unripe fruit of E. rutaecarpa, has been exposed to have anti-inflammatory properties, the mechanism of action has not been well studied. Thus, this study investigated the molecular mechanisms of rutaecarpine (RUT) in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. RUT reserved the production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor (TNF-α), and interleukin (IL)-1ß in the LPS-induced macrophages. RUT showed an inhibitory effect on the mitogen-activated protein kinases (MAPKs), and it also inhibited nuclear transcription factor kappa-B (NF-κB) by hindering IκBα and NF-κB p65 phosphorylation and p65 nuclear translocation. The phospho-PI3K and Akt was concentration-dependently suppressed by RUT. However, RUT not only suggestively reduced the migratory ability of macrophages and their numbers induced by LPS but also inhibited the phospho-Src, and FAK. Taken together, these results indicate that RUT participates a vital role in the inhibition of LPS-induced inflammatory processes in RAW 264.7 macrophages and that the mechanisms involve PI3K/Akt and MAPK-mediated downregulation of NF-κB signaling pathways. Notably, reducing the migration and number of cells induced by LPS via inhibiting of Src/FAK pathway was also included to the anti-inflammatory mechanism of RUT. Therefore, RUT may have potential benefits as a therapeutic agent against chronic inflammatory diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Quinase 1 de Adesão Focal/metabolismo , Alcaloides Indólicos/farmacologia , Macrófagos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Quinazolinas/farmacologia , Animais , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Interleucina-1beta/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Inibidor de NF-kappaB alfa/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
Chemistry ; 26(19): 4246-4250, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012367

RESUMO

The radical-radical coupling reaction is an important synthetic strategy. In this study, the iron-catalyzed radical-radical cross-coupling reaction based on the decarboxylation of keto acids and decarbonylation of aliphatic aldehydes to obtain valuable aryl ketones is reported for the first time. Remarkably, when tertiary aldehydes were used as carbonyl sources, ketone esters were selectively obtained instead of ketones. The gram-scale preparation of aryl ketone through this strategy was easily achieved by using only 3 mol % of the iron catalyst. As a proof-of-concept, the bioactive molecule flurprimidol was synthesized in two steps by using this strategy.

13.
Int J Mol Med ; 45(2): 687, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894260

RESUMO

Following the publication of the above paper, the authors noted that the first author affiliation was presented incorrectly. Essentially, 'School of Medicine' had been omitted from the address. Therefore, the author and affiliation details for this paper should have been presented as follows (the changes are highlighted in bold): THANASEKARAN JAYAKUMAR1*, KAO­CHANG LIN1,2*, WAN-JUNG LU1,3, CHIA­YING LIN4, GERALDINE PITCHAIRAJ5, JIUN­YI LI4,6 and JOEN­RONG SHEU1,4. 1Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, Taipei; 2Department of Neurology, Chi Mei Medical Center, Tainan; 3Department of Medical Research, Taipei Medical University Hospital; 4Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan, R.O.C.; 5Department of Animal Science, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India; Department of Cardiovascular Surgery, Mackay Memorial Hospital, and Mackay Medical College, Taipei, Taiwan, R.O.C. The authors regret that the error with the first author affiliation was not noticed prior to the publication of their paper, and apologize for any inconvenience caused. [The original article was published in International Journal of Molecular Medicine 39: 174­182, 2017; DOI: 10.3892/ijmm.2016.2822].

14.
Int J Mol Sci ; 20(11)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163690

RESUMO

Esculetin, a bioactive 6,7-dihydroxy derivative of coumarin, possesses pharmacological activities against obesity, diabetes, renal failure, and cardiovascular disorders (CVDs). Platelet activation plays a major role in CVDs. Thus, disrupting platelet activation represents an attractive therapeutic target. We examined the effect of esculetin in human platelet activation and experimental mouse models. At 10-80 µM, esculetin inhibited collagen- and arachidonic acid-induced platelet aggregation in washed human platelets. However, it had no effects on other agonists such as thrombin and U46619. Esculetin inhibited adenosine triphosphate release, P-selectin expression, hydroxyl radical (OH·) formation, Akt activation, and phospholipase C (PLC)γ2/protein kinase C (PKC) phosphorylation, but did not diminish mitogen-activated protein kinase phosphorylation in collagen-activated human platelets. Platelet function analysis indicated that esculetin substantially prolonged the closure time of whole blood. In experimental mice, esculetin significantly increased the occlusion time in thrombotic platelet plug formation and reduced mortality associated with acute pulmonary thromboembolism. However, it did not prolong the bleeding time. This study demonstrates that esculetin inhibits human platelet activation via hindering the PLCγ2-PKC cascade, hydroxyl radical formation, Akt activation, and ultimately suppressing platelet activation. Therefore, esculetin may act as an essential therapeutic agent for preventing thromboembolic diseases.


Assuntos
Plaquetas/metabolismo , Trombose/etiologia , Trombose/prevenção & controle , Umbeliferonas/uso terapêutico , Biomarcadores , Plaquetas/efeitos dos fármacos , Humanos , Fosfolipase C gama/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Umbeliferonas/química , Umbeliferonas/farmacologia
15.
J Formos Med Assoc ; 118(12): 1661-1673, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30709695

RESUMO

BACKGROUND & PURPOSE: Following traumatic brain injury (TBI), primary mechanical injury to the brain may cause blood-brain-barrier damage followed by secondary injury, ultimately culminating in cell death. We aimed to test whether one injection of mesenchymal stem cells (MSC) derived from the human umbilical cord can modulate brain cytokine and chemokine gene profiles and attenuate neurological injury in rats with TBI. METHODS: One-day post-TBI, the injured rats were treated with one injection of MSC (4 × 106/rat, i.v.). Three days later, immediately after assessment of neurobehavioral function, animals were sacrificed for analysis of neurological injury (evidenced by both brain contusion volume and neurological deficits) and parietal genes encoding 84 cytokines and chemokines in the injured brain by qPCR methods. RESULTS: Three days post-TBI, rats displayed both neurological injury and upgrade of 11 parietal genes in the ipsilateral brain. One set of 8 parietal genes (e.g., chemokine [C-X-C motif] ligand 12, platelet factor 4, interleukin-7, chemokine [C-C motif] ligand (CCL)19, CCL 22, secreted phosphoprotein 1, pro-platelet basic protein 1, and CCL 2) differentially upgraded by TBI was related to pro-inflammatory and/or neurodegenerative processes. Another set of 3 parietal genes up-graded by TBI (e.g., glucose-6-phosphate isomerase, bone morphogenetic protein (BMP) 2, and BMP 4) was related to anti-inflammatory/neuroregenerative events. Administration of MSC attenuated neurological injury, down-regulated these 8 parietal pro-inflammatory genes, and up-regulated these 3 parietal anti-inflammatory genes in the rats with TBI. CONCLUSION: Our data suggest that modulation of parietal cytokines and chemokines gene profiles by MSC as a basis for neurotrauma recovery.


Assuntos
Lesões Encefálicas Traumáticas/terapia , Quimiocinas/genética , Citocinas/genética , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Animais , Lesões Encefálicas Traumáticas/sangue , Lesões Encefálicas Traumáticas/genética , Modelos Animais de Doenças , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Transcriptoma , Cordão Umbilical/citologia
16.
Cell Physiol Biochem ; 50(1): 150-168, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30278465

RESUMO

BACKGROUND/AIMS: Immunological mechanisms can be triggered as a response to central nervous system insults and can lead to seizures. In this study an investigation was made to determine if glatiramer acetate (GA), an immunomodulator currently used in the treatment of multiple sclerosis, could protect rats from pilocarpine-induced seizures and chronic epilepsy. METHODS: Two groups of adult male Sprague-Dawley rats, experimental (GA) and control, were used in the study. The systemic IL-1α and IL-1ß levels at baseline were checked as well as status epilepticus (SE), and the spontaneous recurrent seizure (SRS) stage by enzyme-linked immunosorbent assay. The GA group was given GA (150 µg/kg, ip) and the control group was given a saline injection prior to pilocarpine-induced seizures. Seizure susceptibility, severity and mortality were evaluated, using Racine seizure classification and hippocampal damage was evaluated by Nissl staining. The GA group received GA (150 µg/kg/day, ip) daily after SE, and the chronic spontaneous seizures were evaluated by long-term video recording, and mossy fiber sprouting was evaluated by Timm staining. The IL-1α and IL-1ß levels were correlated with seizure activities. The TNF-α level in the hippocampus was determined at the SRS stage by immunohistochemistry. The effect of GA on ionic currents and action potentials (APs) in NG108-15 differentiated neurons was investigated using patch-clamp technology. RESULTS: It was found that latency to severe seizures was significantly longer in the GA (p < 0.01) group, which also had SE of shorter duration and less frequent SRS (p < 0.01). GA attenuated acute hippocampal neuron loss and chronic mossy fiber sprouting in the CA3 and the SRS-reduction correlated with the reduction of IL-1α, but not with IL-1ß or TNF-α levels. Mechanistically, GA reduced the peak amplitude of voltage-gated Na+ current (INa), with a negative shift in the inactivation curve of INa and reduced the amplitude of APs along with decreased firing of APs. CONCLUSION: GA might serve as a neuroexcitability modulator which attenuates pilocarpine-induced acute and chronic excitotoxicity. Sodium channel attenuation was partially independent of the immunomodulatory effect.


Assuntos
Acetato de Glatiramer/uso terapêutico , Convulsões/prevenção & controle , Estado Epiléptico/prevenção & controle , Potenciais de Ação/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Modelos Animais de Doenças , Acetato de Glatiramer/farmacologia , Interleucina-1alfa/análise , Interleucina-1beta/análise , Masculino , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Técnicas de Patch-Clamp , Pilocarpina/toxicidade , Ratos , Ratos Sprague-Dawley , Convulsões/induzido quimicamente , Convulsões/patologia , Índice de Gravidade de Doença , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/patologia , Fator de Necrose Tumoral alfa/análise
17.
Cell Physiol Biochem ; 47(1): 330-343, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29768258

RESUMO

BACKGROUND/AIMS: Rotenone (Rot) is known to suppress the activity of complex I in the mitochondrial chain reaction; however, whether this compound has effects on ion currents in neurons remains largely unexplored. METHODS: With the aid of patch-clamp technology and simulation modeling, the effects of Rot on membrane ion currents present in mHippoE-14 cells were investigated. RESULTS: Addition of Rot produced an inhibitory action on the peak amplitude of INa with an IC50 value of 39.3 µM; however, neither activation nor inactivation kinetics of INa was changed during cell exposure to this compound. Addition of Rot produced little or no modifications in the steady-state inactivation curve of INa. Rot increased the amplitude of Ca2+-activated Cl- current in response to membrane depolarization with an EC50 value of 35.4 µM; further addition of niflumic acid reversed Rot-mediated stimulation of this current. Moreover, when these cells were exposed to 10 µM Rot, a specific population of ATP-sensitive K+ channels with a single-channel conductance of 18.1 pS was measured, despite its inability to alter single-channel conductance. Under current clamp condition, the frequency of miniature end-plate potentials in mHippoE-14 cells was significantly raised in the presence of Rot (10 µM) with no changes in their amplitude and time course of rise and decay. In simulated model of hippocampal neurons incorporated with chemical autaptic connection, increased autaptic strength to mimic the action of Rot was noted to change the bursting pattern with emergence of subthreshold potentials. CONCLUSIONS: The Rot effects presented herein might exert a significant action on functional activities of hippocampal neurons occurring in vivo.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Rotenona/farmacologia , Desacopladores/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Linhagem Celular , Transporte de Elétrons/efeitos dos fármacos , Hipocampo/fisiologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Canais de Potássio/metabolismo
18.
Oncotarget ; 9(2): 1992-2001, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29416747

RESUMO

CD34 is a transmembrane phosphoglycoprotein used to selectively enrich bone marrow in hematopoietic stem cells for transplantation. Treating rats with CD34+ cells derived from human umbilical cord blood before or after heat stroke has been shown to promote survival. We investigated whether CD34- human placenta-derived stem cells (PDMSCs) could improve survival following heat stroke in rats. Rats were subjected to heat stress (42°C for 98 min) to induce heat stroke. Intravenous administration of PDMSCs 1 day before or immediately after the onset of heat stroke improved survival by 60% and 20%, respectively. Pre-treatment with CD34- PDMSCs protected against heat stroke injury more effectively than that treatment after injury. PDMSCs treatment attenuated cerebrovascular dysfunction, the inflammatory response, and lipid peroxidation. These data suggest human PDMSCs protect against heat stroke injury in rats. Moreover, these effects do not require the presence of CD34+ cells.

19.
Medicine (Baltimore) ; 96(19): e6943, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28489813

RESUMO

Hospice and palliative care has been recognized as an essential part of emergency medicine; however, there is no consensus on the optimal model for the delivery of hospice and palliative care in the emergency department (ED). Therefore, we conducted a novel implementation in a tertiary medical center in Taiwan. In the preintervention period, we recruited a specialist for hospice and palliative medicine in the ED to lead our intervention. In the early stage of the intervention, starting on July 1, 2014, we encouraged and funded ED physicians and nurses to receive training for hospice and palliative medicine and residents of emergency medicine to rotate to the hospice ward. In the late stage of the intervention, we initiated educational programs in the ED, an interdisciplinary meeting with the hospice team every month, sharing information and experience via a cell phone communication app, and setting aside an emergency hospice room for end-of-life patients. We compared the outcomes among pre-, during, and postintervention periods. Compared with 4 in the preintervention period, the cases of do not resuscitate (DNR) per month increased significantly to 30.1 in the early stage of intervention, 23.9 in late stage of intervention, and 34.6 in the postintervention period (all P < .001 compared with the preintervention period). Compared with 10.8% in the preintervention period, the ratio of DNR orders signed in the ED/total DNR orders signed in the study hospital was increased to 17.1% in early stage of intervention, 12.5% in late stage of intervention, and 22.8% in postintervention. Compared with zero in preintervention and early intervention, the cases of consultation with the hospice team increased significantly to 19 cases per month in the late stage of intervention and postintervention. The ability of nurses in hospice and palliative care, including knowledge and the timing and method of consultation with the hospice team, was also significantly improved. We successfully implemented a novel model of hospice and palliative care in the ED via a champion, education, and close collaboration with the hospice team, which could be an important reference for other EDs and intensive care unit in the future.


Assuntos
Educação Médica , Serviço Hospitalar de Emergência , Cuidados Paliativos na Terminalidade da Vida/métodos , Cuidados Paliativos/métodos , Idoso , Idoso de 80 Anos ou mais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Internato e Residência/métodos , Pessoa de Meia-Idade , Aplicativos Móveis , Modelos Teóricos , Enfermeiras e Enfermeiros , Equipe de Assistência ao Paciente , Médicos , Projetos Piloto , Estudos Prospectivos , Encaminhamento e Consulta/estatística & dados numéricos , Ordens quanto à Conduta (Ética Médica) , Taiwan , Centros de Atenção Terciária
20.
Int J Mol Med ; 39(1): 174-182, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27959381

RESUMO

Nobiletin, a bioactive polymethoxylated flavone, has been described to possess a diversity of biological effects through its antioxidant and anti-inflammatory properties. Vasodilator-stimulated phosphoprotein (VASP) is a common substrate for cyclic AMP and cyclic GMP-regulated protein kinases [i.e., cyclic AMP-dependent protein kinase (PKA; also known as protein kinase A) and cyclic GMP-dependent protein kinase (PKG; also known as protein kinase G)] and it has been shown to be directly phosphorylated by protein kinase C (PKC). In the present study, we demonstrate that VASP is phosphorylated by nobiletin in human platelets via a non-cyclic nucleotide-related mechanism. This was confirmed by the use of inhibitors of adenylate cyclase (SQ22536) and guanylate cyclase [1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ)], since they prevented VASP phosphorylation induced by nobiletin. Furthormore, this event was also not affected by specific inhibitors of PKA (H-89), PKG (KT5823) and PKC (Ro318220), representing cyclic nucleotide-dependent pathways upon nobiletin-induced VASP phosphorylation. Similarly, inhibitors of p38 mitogen-activated protein kinase (MAPK; SB203580), extracellular signal-regulated kinase 2 (ERK2; PD98059), c-Jun N-terminal kinase 1 (JNK1; SP600125), Akt (LY294002) and nuclear factor-κB (NF-κB; Bay11-7082) did not affect nobiletin­induced VASP phosphorylation. Moreover, electron spin resonance, dichlorofluorescein fluorescence and western blotting techniques revealed that nobiletin did not affect hydroxyl radicals (OH•), intracellular reactive oxygen species (ROS) and on protein carbonylation, respectively. Furthermore, the nobiletin­induced VASP phosphorylation was surprisingly reversed by the intracellular antioxidant, N-acetylcysteine (NAC), but not by the inhibitor of NADPH oxidase, diphenyleneiodonium chloride (DPI). It was surprising to observe the differential effects of nobiletin and NAC on VASP phosphorylation in human platelets, since they both have been reported to have antioxidant properties. The likely explanation for this discrepancy is that NAC may bind to allosteric sites on the receptor different from those that nobiletin binds to in human platelets. Taken together, our findings suggest that nobiletin induces VASP phosphorylation in human platelets through non-cyclic nucleotide-related mechanisms. Nevertheless, the exact mechanisms responsible for these effects need to be further confirmed in future studies.


Assuntos
Plaquetas/metabolismo , Moléculas de Adesão Celular/metabolismo , Citrus/química , Flavonas/farmacologia , Flavonoides/farmacologia , Proteínas dos Microfilamentos/metabolismo , Nucleotídeos Cíclicos/metabolismo , Fosfoproteínas/metabolismo , Acetilcisteína/farmacologia , Plaquetas/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Radical Hidroxila/metabolismo , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADPH Oxidases/metabolismo , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Carbonilação Proteica/efeitos dos fármacos , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
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