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1.
Int J Mol Sci ; 24(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36614118

RESUMO

Stroke is a major cause of death and disability across the world, and its detrimental impact should not be underestimated. Therapies are available and effective for ischemic stroke (e.g., thrombolytic recanalization and mechanical thrombectomy); however, there are limitations to therapeutic interventions. Recanalization therapy has developed dramatically, while the use of adjunct neuroprotective agents as complementary therapies remains deficient. Pathological TAR DNA-binding protein (TDP-43) has been identified as a major component of insoluble aggregates in numerous neurodegenerative pathologies, including ALS, FTLD and Alzheimer's disease. Here, we show that increased pathological TDP-43 fractions accompanied by impaired mitochondrial function and increased gliosis were observed in an ischemic stroke rat model, suggesting a pathological role of TDP-43 in ischemic stroke. In ischemic rats administered rapamycin, the insoluble TDP-43 fraction was significantly decreased in the ischemic cortex region, accompanied by a recovery of mitochondrial function, the attenuation of cellular apoptosis, a reduction in infarct areas and improvements in motor defects. Accordingly, our results suggest that rapamycin provides neuroprotective benefits not only by ameliorating pathological TDP-43 levels, but also by reversing mitochondrial function and attenuating cell apoptosis in ischemic stroke.


Assuntos
Esclerose Lateral Amiotrófica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Ratos , Sirolimo/farmacologia , Sirolimo/uso terapêutico , AVC Isquêmico/tratamento farmacológico , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Apoptose , Esclerose Lateral Amiotrófica/patologia
2.
J Neurotrauma ; 38(10): 1445-1449, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25747875

RESUMO

Over 2 million people suffer from mild traumatic brain injury (mTBI) each year. Predicting symptoms of mTBI and the characterization of those symptoms has been challenging. Biomarkers that correlate clinical symptoms to disease outcome are desired to improve understanding of the disease and optimize patient care. Bone marrow kinase on chromosome X (BMX), a member of the TEC family of nonreceptor tyrosine kinases, is up-regulated after traumatic neural injury in a rat model of mTBI. The aim of this investigation was to determine whether BMX serum concentrations can effectively be used to predict outcomes after mTBI in a clinical setting. A total of 63 patients with mTBI (Glasgow Coma Score [GCS] between 13 and 15) were included. Blood samples taken at the time of hospital admission were analyzed for BMX. Data collected included demographic and clinical variables. Outcomes were assessed using the Dizziness Handicap Inventory (DHI) questionnaire at baseline and 6 weeks postinjury. The participant was asssigned to the case group if the subject's complaints of dizziness became worse at the sixth week assessment; otherwise, the participant was assigned to the control group. A receiver operating characteristic curve was constructed to explore BMX level. Significant associations were found between serum levels of BMX and dizziness. Areas under the curve for prediction of change in DHI postinjury were 0.76 for total score, 0.69 for physical score, 0.65 for emotional score, and 0.66 for functional score. Specificities were between 0.69 and 0.77 for total score and emotional score, respectively. Therefore, BMX demonstrates potential as a candidate serum biomarker of exacerbating dizziness post-mTBI.


Assuntos
Concussão Encefálica/sangue , Concussão Encefálica/complicações , Tontura/sangue , Tontura/etiologia , Proteínas Tirosina Quinases/sangue , Adulto , Idoso , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Int J Mol Sci ; 21(8)2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32326191

RESUMO

BACKGROUND: Stroke is one of the leading causes of death and disability worldwide and places a heavy burden on the economy in our society. Current treatments, such as the use of thrombolytic agents, are often limited by a narrow therapeutic time window. However, the regeneration of the brain after damage is still active days, even weeks, after stroke occurs, which might provide a second window for treatment. Emodin, a traditional Chinese medicinal herb widely used to treat acute hepatitis, has been reported to possess antioxidative capabilities and protective effects against myocardial ischemia/reperfusion injury. However, the underlying mechanisms and neuroprotective functions of Emodin in a rat middle cerebral artery occlusion (MCAO) model of ischemic stroke remain unknown. This study investigates neuroprotective effects of Emodin in ischemia both in vitro and in vivo. METHODS: PC12 cells were exposed to oxygen-glucose deprivation to simulate hypoxic injury, and the involved signaling pathways and results of Emodin treatment were evaluated. The therapeutic effects of Emodin in ischemia animals were further investigated. RESULTS: Emodin reduced infarct volume and cell death following focal cerebral ischemia injury. Emodin treatment restored PC12 cell viability and reduced reactive oxygen species (ROS) production and glutamate release under conditions of ischemia/hypoxia. Emodin increased Bcl-2 and glutamate transporter-1 (GLT-l) expression but suppressed activated-caspase 3 levels through activating the extracellular signal-regulated kinase (ERK)-1/2 signaling pathway. CONCLUSION: Emodin induced Bcl-2 and GLT-1 expression to inhibit neuronal apoptosis and ROS generation while reducing glutamate toxicity via the ERK-1/2 signaling pathway. Furthermore, Emodin alleviated nerve cell injury following ischemia/reperfusion in a rat MCAO model. Emodin has neuroprotective effects against ischemia/reperfusion injury both in vitro and in vivo, which may be through activating the ERK-1/2 signaling pathway.


Assuntos
Emodina/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Animais , Biomarcadores , Sobrevivência Celular , Suscetibilidade a Doenças , Hipóxia/metabolismo , Imuno-Histoquímica , Células PC12 , Ratos , Traumatismo por Reperfusão/tratamento farmacológico
4.
Cell Transplant ; 28(4): 439-450, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31094216

RESUMO

Stroke is a leading cause of death and severe disability worldwide. After cerebral ischemia, inflammation plays a central role in the development of permanent neurological damage. Reactive oxygen species (ROS) are involved in the mechanism of post-ischemic inflammation. The activation of several inflammatory enzymes produces ROS, which subsequently suppress mitochondrial activity, leading to further tissue damage. Pomalidomide (POM) is a clinically available immunomodulatory and anti-inflammatory agent. Prior cellular studies demonstrate that POM can mitigate oxidative stress and lower levels of pro-inflammatory cytokines, particularly TNF-α, which plays a prominent role in ischemic stroke-induced brain damage and functional deficits. To evaluate the potential value of POM in cerebral ischemia, POM was initially administered to transgenic mice chronically over-expressing TNF-α surfactant protein (SP)-C promoter (SP-C/TNF-α mice) to assess whether systemically administered drug could lower systemic TNF-α level. POM significantly lowered serum levels of TNF-α and IL-5. Pharmacokinetic studies were then undertaken in mice to evaluate brain POM levels following systemic drug administration. POM possessed a brain/plasma concentration ratio of 0.71. Finally, rats were subjected to transient middle cerebral artery occlusion (MCAo) for 60 min, and subsequently treated with POM 30 min thereafter to evaluate action on cerebral ischemia. POM reduced the cerebral infarct volume in MCAo-challenged rats and improved motor activity, as evaluated by the elevated body swing test. POM's neuroprotective actions on ischemic injury represent a potential therapeutic approach for ischemic brain damage and related disorders, and warrant further evaluation.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Talidomida/análogos & derivados , Inibidores da Angiogênese/farmacologia , Animais , Masculino , Camundongos , Ratos , Talidomida/farmacologia , Talidomida/uso terapêutico
5.
Behav Neurol ; 2019: 4364592, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31110595

RESUMO

Introduction. Over 1 million mild traumatic brain injury (mTBI) cases are reported annually worldwide and may result in cognitive, physical, and emotional deterioration; depression; anxiety; and sleep problems. However, studies on long-term mTBI effects are limited. This study included 440 patients, and regular follow-ups of psychological assessments were performed for 2 years. Four questionnaires, including the Pittsburgh sleep quality index (PSQI), Epworth sleepiness scale (ESS), Beck's anxiety inventory (BAI), and Beck's depression inventory (BDI), were used to evaluate sleep problems, daytime sleepiness, anxiety, and depression, respectively. Results show that BAI and BDI scores considerably improved at the 6th-week, 1st-year, and 2nd-year follow-ups compared to baseline, yet these remained significantly different. In addition, anxiety and depression were prominent symptoms in a select subgroup of patients with poor initial evaluations, which improved over the 2 years. However, the ESS and PSQI scores fluctuated only mildly over the same time span. In conclusion, the mTBI patients showed a gradual improvement of anxiety and depression over the 2 years following injury. While anxiety and depression levels for mTBI patients in general did not return to premorbid status, improvements were observed. Sleep disorders persisted and were consistent with initial levels of distress.


Assuntos
Concussão Encefálica/complicações , Concussão Encefálica/psicologia , Adulto , Ansiedade/psicologia , Depressão/psicologia , Transtorno Depressivo , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Psicometria/métodos , Sono , Transtornos do Sono-Vigília/psicologia , Inquéritos e Questionários
6.
Int J Mol Sci ; 19(10)2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30347766

RESUMO

Due to its high oxygen demand and abundance of peroxidation-susceptible lipid cells, the brain is particularly vulnerable to oxidative stress. Induced by a redox state imbalance involving either excessive generation of reactive oxygen species (ROS) or dysfunction of the antioxidant system, oxidative stress plays a central role in a common pathophysiology that underpins neuronal cell death in acute neurological disorders epitomized by stroke and chronic ones such as Alzheimer's disease. After cerebral ischemia, for example, inflammation bears a key responsibility in the development of permanent neurological damage. ROS are involved in the mechanism of post-ischemic inflammation. The activation of several inflammatory enzymes produces ROS, which subsequently suppress mitochondrial activity, leading to further tissue damage. Pomalidomide (POM) is a clinically available immunomodulatory and anti-inflammatory agent. Using H2O2-treated rat primary cortical neuronal cultures, we found POM displayed neuroprotective effects against oxidative stress and cell death that associated with changes in the nuclear factor erythroid derived 2/superoxide dismutase 2/catalase signaling pathway. POM also suppressed nuclear factor kappa-light-chain-enhancer (NF-κB) levels and significantly mitigated cortical neuronal apoptosis by regulating Bax, Cytochrome c and Poly (ADP-ribose) polymerase. In summary, POM exerted neuroprotective effects via its anti-oxidative and anti-inflammatory actions against H2O2-induced injury. POM consequently represents a potential therapeutic agent against brain damage and related disorders and warrants further evaluation.


Assuntos
Antioxidantes/farmacologia , Apoptose , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Talidomida/análogos & derivados , Animais , Células Cultivadas , Córtex Cerebral/citologia , Peróxido de Hidrogênio/toxicidade , Neurônios/metabolismo , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Talidomida/farmacologia
7.
Brain Res ; 1677: 118-128, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28963051

RESUMO

Stroke commonly leads to adult disability and death worldwide. Its major symptoms are spastic hemiplegia and discordant motion, consequent to neuronal cell death induced by brain vessel occlusion. Acetylcholinesterase (AChE) is upregulated and allied with inflammation and apoptosis after stroke. Recent studies suggest that AChE inhibition ameliorates ischemia-reperfusion injury and has neuroprotective properties. (-)-Phenserine, a reversible AChE inhibitor, has a broad range of actions independent of its AChE properties, including neuroprotective ones. However, its protective effects and detailed mechanism of action in the rat middle cerebral artery occlusion model (MCAO) remain to be elucidated. This study investigated the therapeutic effects of (-)-phenserine for stroke in the rat focal cerebral ischemia model and oxygen-glucose deprivation/reperfusion (OGD/RP) damage model in SH-SY5Y neuronal cultures. (-)-Phenserine mitigated OGD/PR-induced SH-SY5Y cell death, providing an inverted U-shaped dose-response relationship between concentration and survival. In MCAO challenged rats, (-)-phenserine reduced infarction volume, cell death and improved body asymmetry, a behavioral measure of stoke impact. In both cellular and animal studies, (-)-phenserine elevated brain-derived neurotrophic factor (BDNF) and B-cell lymphoma 2 (Bcl-2) levels, and decreased activated-caspase 3, amyloid precursor protein (APP) and glial fibrillary acidic protein (GFAP) expression, potentially mediated through the ERK-1/2 signaling pathway. These actions mitigated neuronal apoptosis in the stroke penumbra, and decreased matrix metallopeptidase-9 (MMP-9) expression. In synopsis, (-)-phenserine significantly reduced neuronal damage induced by ischemia/reperfusion injury in a rat model of MCAO and cellular model of OGD/RP, demonstrating that its anti-apoptotic/neuroprotective/neurotrophic cholinergic and non-cholinergic properties warrant further evaluation in conditions of brain injury.


Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fisostigmina/análogos & derivados , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/fisiologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Inibidores da Colinesterase/farmacologia , Relação Dose-Resposta a Droga , Glucose/deficiência , Humanos , Masculino , Neurônios/metabolismo , Neurônios/patologia , Fisostigmina/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia
8.
Acta Neurol Taiwan ; 26(1): 13-19, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28752509

RESUMO

PURPOSE: Mild traumatic brain injury (mTBI) is a major public health concern. The apolipoprotein E (APOE) gene contains three polymorphisms, and the APOE4 polymorphism may affect several physiological states, such as the recovery from mTBI as well as sleep. This study aims to investigate the association between APOE4 with the recovery of sleep disturbance after mTBI. METHODS: From May 2012 to Aug 2015, 189 mTBI patients completed baseline (1st week post-mTBI) and follow-up (6th week post-mTBI) sleep assessments that involved using the Pittsburgh Sleep Quality Index (PSQI). APOE genotypes were determined by sequencing the products of polymerase chain reaction from genomic DNA. Statistical analyses were performed using the Wilcox signed-rank or chi-square test. RESULTS: Thirty-five (18.5%) participants were APOE4 carriers. At baseline, the demographic data and the severity of sleep disturbance were similar in both groups. APOE4 carriers demonstrated significant improvement in the overall PSQI score (8.34±3.9 at baseline and 7.43±3.99 at follow-up, p = 0.05) and scores of several PSQI subscales, including sleep disturbance, sleep latency, daytime dysfunction caused by sleepiness, and overall sleep quality, which was similar to APOE4 noncarriers. CONCLUSION: APOE4 is not associated with the recovery of sleep disturbance after mTBI.


Assuntos
Apolipoproteína E4 , Concussão Encefálica , Transtornos do Sono-Vigília , Alelos , Apolipoproteína E4/genética , Concussão Encefálica/complicações , Concussão Encefálica/genética , Humanos , Polimorfismo Genético , Transtornos do Sono-Vigília/genética
9.
Nucleic Acids Res ; 45(10): 6011-6022, 2017 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-28334864

RESUMO

Frameshifting is an essential process that regulates protein synthesis in many viruses. The ribosome may slip backward when encountering a frameshift motif on the messenger RNA, which usually contains a pseudoknot structure involving tertiary base pair interactions. Due to the lack of detailed molecular explanations, previous studies investigating which features of the pseudoknot are important to stimulate frameshifting have presented diverse conclusions. Here we constructed a bimolecular pseudoknot to dissect the interior tertiary base pairs and used single-molecule approaches to assess the structure targeted by ribosomes. We found that the first ribosome target stem was resistant to unwinding when the neighboring loop was confined along the stem; such constrained conformation was dependent on the presence of consecutive adenosines in this loop. Mutations that disrupted the distal base triples abolished all remaining tertiary base pairs. Changes in frameshifting efficiency correlated with the stem unwinding resistance. Our results demonstrate that various tertiary base pairs are coordinated inside a highly efficient frameshift-stimulating RNA pseudoknot and suggest a mechanism by which mechanical resistance of the pseudoknot may persistently act on translocating ribosomes.


Assuntos
Pareamento de Bases , Mudança da Fase de Leitura do Gene Ribossômico/fisiologia , Conformação de Ácido Nucleico , RNA Mensageiro/química , Ribossomos/metabolismo , Transferência Ressonante de Energia de Fluorescência , Modelos Moleculares , Ressonância Magnética Nuclear Biomolecular , Oligorribonucleotídeos/síntese química , Oligorribonucleotídeos/química , Pinças Ópticas , RNA Mensageiro/genética , Fases de Leitura , Especificidade por Substrato
10.
J Biomed Sci ; 23(1): 72, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27769241

RESUMO

BACKGROUND: In the central nervous system regions of the sporadic and familial FTLD and ALS patients, TDP-43 has been identified as the major component of UBIs inclusions which is abnormally hyperphosphorylated, ubiquitinated, and cleaved into C-terminal fragments to form detergent-insoluble aggregates. So far, the effective drugs for FTLD and ALS neurodegenerative diseases are yet to be developed. Autophagy has been demonstrated as the major metabolism route of the pathological TDP-43 inclusions, hence activation of autophagy is a potential therapeutic strategy for TDP-43 pathogenesis in FTLD and ALS. Berberine, a traditional herbal medicine, is an inhibitor of mTOR signal and an activator for autophagy. Berberine has been implicated in several kinds of diseases, including the neuronal-related pathogenesis, such as Parkinson's, Huntington's and Alzheimer's diseases. However, the therapeutic effect of berberine on FTLD or ALS pathology has never been investigated. RESULTS: Here we studied the molecular mechanism of berberine in cell culture model with TDP-43 proteinopathies, and found that berberine is able to reverse the processing of insoluble TDP-43 aggregates formation through deregulation of mTOR/p70S6K signal and activation of autophagic degradation pathway. And inhibition of autophagy by specific autophagosome inhibitor, 3-MA, reverses the effect of berberine on reducing the accumulation of insoluble TDP-43 and aggregates formation. These results gave us the notion that inhibition of autophagy by 3-MA reverses the effect of berberine on TDP-43 pathogenesis, and activation of mTOR-regulated autophagy plays an important role in berberine-mediated therapeutic effect on TDP-43 proteinopathies. CONCLUSION: We supported an important notion that the traditional herb berberine is a potential alternative therapy for TDP-43-related neuropathology. Here we demonstrated that berberine is able to reverse the processing of insoluble TDP-43 aggregates formation through deregulation of mTOR/p70S6K signal and activation of autophagic degradation pathway. mTOR-autophagy signals plays an important role in berberine-mediated autophagic clearance of TDP-43 aggregates. Exploring the detailed mechanism of berberine on TDP-43 proteinopathy provides a better understanding for the therapeutic development in FTLD and ALS.


Assuntos
Esclerose Lateral Amiotrófica/terapia , Berberina/uso terapêutico , Degeneração Lobar Frontotemporal/terapia , Proteinopatias TDP-43/terapia , Esclerose Lateral Amiotrófica/genética , Animais , Linhagem Celular Tumoral , Degeneração Lobar Frontotemporal/genética , Camundongos , Proteinopatias TDP-43/genética
11.
J Neurotrauma ; 33(22): 2044-2054, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-26972789

RESUMO

Mild traumatic brain injury (mTBI) is a major public health issue, representing 75-90% of all cases of TBI. In clinical settings, mTBI, which is defined as a Glascow Coma Scale (GCS) score of 13-15, can lead to various physical, cognitive, emotional, and psychological-related symptoms. To date, there are no pharmaceutical-based therapies to manage the development of the pathological deficits associated with mTBI. In this study, the neurotrophic and neuroprotective properties of glucose-dependent insulinotropic polypeptide (GIP), an incretin similar to glucagon-like peptide-1 (GLP-1), was investigated after its steady-state subcutaneous administration, focusing on behavior after mTBI in an in vivo animal model. The mTBI rat model was generated by a mild controlled cortical impact (mCCI) and used to evaluate the therapeutic potential of GIP. We used the Morris water maze and novel object recognition tests, which are tasks for spatial and recognition memory, respectively, to identify the putative therapeutic effects of GIP on cognitive function. Further, beam walking and the adhesive removal tests were used to evaluate locomotor activity and somatosensory functions in rats with and without GIP administration after mCCI lesion. Lastly, we used immunohistochemical (IHC) staining and Western blot analyses to evaluate the inflammatory markers, glial fibrillary acidic protein (GFAP), amyloid-ß precursor protein (APP), and bone marrow tyrosine kinase gene in chromosome X (BMX) in animals with mTBI. GIP was well tolerated and ameliorated mTBI-induced memory impairments, poor balance, and sensorimotor deficits after initiation in the post-injury period. In addition, GIP mitigated mTBI-induced neuroinflammatory changes on GFAP, APP, and BMX protein levels. These findings suggest GIP has significant benefits in managing mTBI-related symptoms and represents a novel strategy for mTBI treatment.


Assuntos
Concussão Encefálica/tratamento farmacológico , Disfunção Cognitiva/tratamento farmacológico , Polipeptídeo Inibidor Gástrico/administração & dosagem , Mediadores da Inflamação/antagonistas & inibidores , Desempenho Psicomotor/efeitos dos fármacos , Animais , Concussão Encefálica/metabolismo , Concussão Encefálica/psicologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/psicologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/psicologia , Mediadores da Inflamação/metabolismo , Injeções Subcutâneas , Masculino , Desempenho Psicomotor/fisiologia , Ratos , Ratos Sprague-Dawley
12.
Molecules ; 19(6): 7341-55, 2014 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-24905604

RESUMO

Glutamate sensors based on the immobilization of glutamate oxidase (GlutOx) were prepared by adsorption on electrodeposited chitosan (Method 1) and by crosslinking with glutaraldehyde (Method 2) on micromachined platinum microelectrodes. It was observed that glutamate sensors prepared by Method 1 have faster response time (<2 s) and lower detection limit (2.5±1.1 µM) compared to that prepared by Method 2 (response time: <5 sec and detection limit: 6.5±1.7 µM); glutamate sensors prepared by Method 2 have a larger linear detection range (20-352 µM) and higher sensitivity (86.8±8.8 nA·µM-1·cm-2, N=12) compared to those prepared by Method 1 (linear detection range: 20-217 µM and sensitivity: 34.9±4.8 nA·µM-1·cm-2, N=8). The applicability of the glutamate sensors in vivo was also demonstrated. The glutamate sensors were implanted into the rat brain to monitor the stress-induced extracellular glutamate release in the hypothalamus of the awake, freely moving rat.


Assuntos
Enzimas Imobilizadas/metabolismo , Aminoácido Oxirredutases/metabolismo , Animais , Quitosana/química , Ácido Glutâmico/metabolismo , Glutaral/química , Hipotálamo/metabolismo , Masculino , Microeletrodos , Ratos , Ratos Sprague-Dawley
13.
Pediatr Neonatol ; 54(2): 73-81, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23590950

RESUMO

Head trauma is one of the most challenging fields of traumatology and demands immediate attention and intervention by first-line clinicians. Symptoms can vary from victim to victim and according to the victim's age, leading to difficulties in making timely and accurate decisions at the point of care. In children, falls, accidents while playing, sports injuries, and abuse are the major causes of head trauma. Traffic accidents are the main cause of disability and death in adolescents and adults. Injury sites include facial bones, muscles, ligaments, vessels, joints, nerves, and focal or whole-brain injuries. Of particular importance are cranial and intracranial injuries. A closed injury occurs when the head suddenly and violently hits an object but the object does not break through the skull. A penetrating injury occurs when an object pierces the skull and affects the brain tissue. Early diagnosis and proper management are crucial to treat patients with potentially life-threatening head and neck trauma. In this review, we discuss the different cases of traumatic brain injury and summarize the current therapies and neuroprotective strategies as well as the related outcomes for children with traumatic brain injury.


Assuntos
Lesões Encefálicas/terapia , Lesões Encefálicas/classificação , Lesões Encefálicas/diagnóstico , Criança , Humanos , Tomografia Computadorizada por Raios X
14.
Cell Transplant ; 21(1): 345-54, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21929872

RESUMO

Etk/Bmx (epithelial and endothelial tyrosine kinase, also known as BMX), a member of the Tec (tyrosine kinase expressed in hepatocellular carcinoma) family of protein-tyrosine kinases, is an important regulator of signal transduction for the activation of cell growth, differentiation, and development. We have previously reported that activation of Etk leads to apoptosis in MDA-MB-468 cells. The purpose of this study was to examine the role of Etk in neuronal injury induced by H(2)O(2) or ischemia. Using Western blot analysis and immunohistochemistry, we found that treatment with H(2)O(2) significantly enhanced phosphorylation of Etk and its downstream signaling molecule Stat1 in primary cortical neurons. Inhibiting Etk activity by LFM-A13 or knocking down Etk expression by a specific shRNA increased the survival of primary cortical neurons. Similarly, at 1 day after a 60-min middle cerebral artery occlusion (MCAo) in adult rats, both phosphorylated Etk and Stat1 were coexpressed with apoptotic markers in neurons in the penumbra. Pretreatment with LFM-A13 or an adenoviral vector encoding the kinase deletion mutant Etkk attenuated caspase-3 activity and infarct volume in ischemic brain. All together, our data suggest that Etk is activated after neuronal injury. Suppressing Etk activity protects against neurodegeneration in ischemic brain.


Assuntos
Isquemia Encefálica/metabolismo , Córtex Cerebral/metabolismo , Peróxido de Hidrogênio/farmacologia , Neurônios/metabolismo , Proteínas Tirosina Quinases/metabolismo , Amidas/farmacologia , Animais , Apoptose , Isquemia Encefálica/terapia , Caspase 3/biossíntese , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Sobrevivência Celular/genética , Córtex Cerebral/citologia , Nitrilas/farmacologia , Fosforilação/efeitos dos fármacos , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Interferência de RNA , RNA Interferente Pequeno , Ratos , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais
16.
Acta Neurol Belg ; 111(1): 22-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21510229

RESUMO

External ventricular drain (EVD) placement is one of the most basic and common neurosurgical procedure which most was performed by young neurosurgical trainees. This study is conducted to determinate the safe and accuracy of EVD placement by freehand method. About 129 EVD placements were evaluated in this study. Eighty-three catheters (64.3%) were located in the ipsilateral frontal horn or third ventricle. The functional accuracy was 86%. Of eighteen misplaced catheters, only 4 (3.1%) catheters were nonfunctional, requiring a replacement or reposition. The higher misplaced rate was significantly observed in patients whose head CT scans revealed the lower hydrocephalus ratio (28.85%) and the smaller ventricular size (5.6 mm). Twenty-one (16.2%) new hemorrhages associated with EVD placements were observed. Using the freehand method, EVD placement is a safe and effective procedure in management of these emergent neurosurgical diseases.


Assuntos
Ventrículos Cerebrais/cirurgia , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Drenagem/efeitos adversos , Hemorragia/etiologia , Hemorragia/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ventrículos Cerebrais/patologia , Falha de Equipamento , Feminino , Hemorragia/diagnóstico por imagem , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
17.
Pediatr Neonatol ; 52(1): 42-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21385657

RESUMO

Dandy-Walker syndrome (DWS) is a congenital brain malformation involving the cerebellum and fourth ventricle. We report a 6-month-old girl with DWS presenting an initially normal ventricular system and mild cyst-like lesion over the posterior fossa as assessed by postnatal brain sonography. However, symptoms and signs of increased intracranial cerebral pressure in terms of frequent vomiting and tense anterior fontanel developed, and these were associated with mild hypotonia and poor neck support, and upward-gaze palsy at the age of 6 months. Magnetic resonance imaging revealed a huge cystic lesion of the fourth ventricle, which filled the posterior fossa and ventricular dilatation. The tentorium was progressively displaced upward by the cyst. A nearly complete agenesis of the cerebellar vermis was also confirmed. After a successful endoscopic third ventriculostomy, a series of brain magnetic resonance imaging scans, taken during a follow-up survey, showed normal lateral and third ventricles. Consequently, symptoms of intracranial cerebral pressure resolved, and a developmental milestone was achieved. In conclusion, DWS can be confirmed postpartum, and endoscopic third ventriculostomy was found to be a preferential operative procedure for DWS with hydrocephalus. It may be effective for patients younger than 1 year.


Assuntos
Síndrome de Dandy-Walker/cirurgia , Hidrocefalia/cirurgia , Neuroendoscopia/métodos , Terceiro Ventrículo/cirurgia , Ventriculostomia/métodos , Síndrome de Dandy-Walker/diagnóstico , Feminino , Humanos , Hidrocefalia/diagnóstico , Lactente , Imageamento por Ressonância Magnética
18.
J Clin Neurosci ; 17(6): 779-81, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20303762

RESUMO

Chorea that occurs as a result of a stroke is rare. We report a patient who developed hemiplegia following an acute hemorrhagic stroke in the left cerebral peduncle and subthalamus; although he had recovered gradually from the severe limb weakness, monochorea occurred 6 months later. Pallidotomy eliminated this symptom and we found it is a safe treatment for medically intractable post-stroke chorea after hemiplegia has resolved.


Assuntos
Coreia/cirurgia , Palidotomia/métodos , Coreia/diagnóstico , Coreia/etiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações , Tomografia Computadorizada por Raios X/métodos
19.
Kaohsiung J Med Sci ; 26(3): 144-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20227654

RESUMO

Stereotactic radiosurgery plays an important role in management of metastatic brain tumors, especially when the tumor has recurred after treatment with previous whole brain radiotherapy. Most metastatic brain tumors less than 1 cm(3) show a complete response after stereotactic radio-surgery. However, there are few reports of a dramatic change in the complete response of large metastatic brain tumors. Here, we report a case of adenocarcinoma of lung that had metastasized to the brain. Because the recurrence of the metastatic brain tumor measured approximately 3 cm in diameter, the tumor was previously treated with two prior craniotomies followed by whole brain radiation to the resection cavity. The tumor subsequently recurred and was treated with stereotactic radiosurgery (CyberKnife). A dramatic response was noted 3 months after radiosurgery with complete disappearance of the recurrent tumor.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Radiocirurgia/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
20.
J Emerg Med ; 38(5): 593-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18281177

RESUMO

Type III odontoid fractures of the axis are the second most common injuries of the cervical spine. Most of these result from motor vehicle accidents and falls. Occult odontoid fractures without preceding trauma are rarely reported in the literature and may be difficult to diagnose. We report the case of a healthy patient who had no history of trauma, but sustained sudden pain in the neck and guarding during head movement after sleep. Initial radiographs of the cervical spine including open-mouth, anterior-posterior, and lateral views did not reveal any obvious fractures. Type III odontoid fracture was uneventfully diagnosed via high-quality three-dimensional reconstruction of computed tomography. The possible mechanism was hyperextension of the neck during the change from the supine to the sitting position. Type III odontoid fractures can occur in the absence of major trauma. The usefulness of computed tomography is emphasized and the literature is also reviewed.


Assuntos
Fraturas Ósseas/complicações , Hipestesia/etiologia , Cervicalgia/etiologia , Processo Odontoide/lesões , Fraturas Ósseas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Processo Odontoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X
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