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1.
J Hepatol ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972484

RESUMO

BACKGROUND AND AIM: The induction of effective CD8+ T cells is thought to play a critical role in the functional cure of chronic hepatitis B (CHB). Additionally, the use of checkpoint inhibitors is being evaluated to overcome T cell dysfunction during CHB. APPROACH AND RESULTS: A chimpanzee adenoviral vector (ChAdOx1-HBV) and a Modified vaccinia Ankara boost (MVA-HBV) encoding the inactivated polymerase, core, and S region from a consensus genotype C HBV were studied. The trial enrolled 55 patients with virally-suppressed CHB virus infection and HBsAg <4,000 IU/mL Group 1 received MVA-HBV intramuscularly (IM) on Day 0 and 28, Group 2 received ChAdOx1-HBV on Day 0/MVA-HBV on Day 28 (VTP-300), Group 3 received VTP-300 + low-dose nivolumab (LDN) on Day 28, and Group 4 received VTP-300 plus LDN with both injections. VTP-300 alone and in combination with LDN was well tolerated with no treatment-related serious adverse events. Reductions of HBsAg were demonstrated in the VTP-300 group 2: 3 of 18 patients with starting HBsAg < 50 IU/ml had durable log10 declines > 0.7 log10 2 months post last-dose. Group 3 (N=18) had reductions in HBsAg of 0.76 log10 and 0.80 log10 3 (p<0.001) at 2 and 7 months post last dose. Two developed persistent non-detectable HBsAg levels. CD4+ and CD8+ antigen-specific T cell responses were generated and there was a correlation between IFN-y ELISpot response and HBsAg decline in Group 2. CONCLUSIONS: VTP-300 induced CD4+ and CD8+ T cells and lowered HBsAg in a subset of patients with baseline values below 100 IU/ml. The addition of LDN resulted in significant reduction in surface antigen. VTP-300 is a promising immunotherapeutic to move forward alone or in combination therapies. IMPACT AND IMPLICATIONS: The induction of potent, durable CD8+ T cells may be critical to achieving a functional cure in chronic hepatitis B virus infection. A prime-boost immunotherapeutic consisting of an adenoviral-vector encoding hepatitis B antigens followed by a pox virus boost was shown to induce CD8+ T cells and to lower HBsAg in CHB patients, either alone or more impactfully when administered in conjunction with a checkpoint inhibitor. The use of immunotherapeutics CLINTRIALS: NCT047789.

2.
Anaesthesia ; 71(1): 31-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26460721

RESUMO

In patients with limited mouth opening, traditional laryngoscopy and videolaryngoscopes are not useful when performing nasotracheal intubation. Eighty patients with limited mouth opening who required nasotracheal intubation were randomly assigned to either fibreoptic intubation (n = 40) or the Trachway(®) (n = 40). Using the modified nasal intubation difficulty scale, 22 (55%) patients who received fibreoptic intubation were categorised as no difficulty compared with 40 (100%) patients in the Trachway group (p < 0.001). Mean (SD) total intubation time was 71.8 (23.3) s in patients who received fibreoptic intubation compared with 35.4 (9.8) s in the Trachway group (p < 0.001). We conclude that the Trachway technique for nasotracheal intubation is quicker and easier compared with fibreoptic intubation in patients with limited mouth opening.


Assuntos
Intubação Intratraqueal/métodos , Gravação em Vídeo/instrumentação , Adulto , Idoso , Feminino , Tecnologia de Fibra Óptica , Humanos , Intubação Intratraqueal/instrumentação , Masculino , Pessoa de Meia-Idade , Boca , Fatores de Tempo
3.
Mol Psychiatry ; 19(5): 536-43, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24589887

RESUMO

Converging epidemiological studies indicate that cannabis abuse during adolescence increases the risk of developing psychosis and prefrontal cortex (PFC)-dependent cognitive impairments later in life. However, the mechanisms underlying the adolescent susceptibility to chronic cannabis exposure are poorly understood. Given that the psychoactive constituent of cannabis binds to the CB1 cannabinoid receptor, the present study was designed to determine the impact of a CB1 receptor agonist (WIN) during specific windows of adolescence on the functional maturation of the rat PFC. By means of local field potential recordings and ventral hippocampal stimulation in vivo, we found that a history of WIN exposure during early (postnatal days - P35-40) or mid-(P40-45) adolescence, but not in late adolescence (P50-55) or adulthood (P75-80), is sufficient to yield a state of frequency-dependent prefrontal disinhibition in adulthood comparable to that seen in the juvenile PFC. Remarkably, this prefrontal disinhibition could be normalized following a single acute local infusion of the GABA-Aα1 positive allosteric modulator Indiplon, suggesting that adolescent exposure to WIN causes a functional downregulation of GABAergic transmission in the PFC. Accordingly, in vitro recordings from adult rats exposed to WIN during adolescence demonstrate that local prefrontal GABAergic transmission onto layer V pyramidal neurons is markedly reduced to the level seen in the P30-35 PFC. Together, these results indicate that early and mid-adolescence constitute a critical period during which repeated CB1 receptor stimulation is sufficient to elicit an enduring state of PFC network disinhibition resulting from a developmental impairment of local prefrontal GABAergic transmission.


Assuntos
Benzoxazinas/farmacologia , Fármacos do Sistema Nervoso Central/farmacologia , Morfolinas/farmacologia , Naftalenos/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/crescimento & desenvolvimento , Receptor CB1 de Canabinoide/agonistas , Ácido gama-Aminobutírico/metabolismo , Animais , Benzodiazepinas/farmacologia , Estimulação Elétrica , Moduladores GABAérgicos/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/crescimento & desenvolvimento , Hipocampo/fisiologia , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/fisiologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Técnicas de Patch-Clamp , Piperidinas/farmacologia , Córtex Pré-Frontal/fisiologia , Células Piramidais/efeitos dos fármacos , Células Piramidais/crescimento & desenvolvimento , Células Piramidais/fisiologia , Pirazóis/farmacologia , Distribuição Aleatória , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/metabolismo , Receptores de GABA-A/metabolismo , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia , Tiofenos/farmacologia
4.
Eur J Clin Microbiol Infect Dis ; 34(1): 55-62, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25037870

RESUMO

Cirrhosis patients have immunologic insufficiency and a high seroprevalence of human herpesvirus type 8 (HHV-8). Nearly all hepatocellular carcinoma (HCC) patients are cirrhotic and have immunoabnormalities. This study aimed to assess the HHV-8 seroprevalence and hemograms in HCC patients. Blood samples from 95 HCC patients, 95 age-, sex-, and Child-Pugh class-matched cirrhotics, and 95 age- and sex-matched healthy controls were analyzed for anti-HHV-8 antibodies, HHV-8 DNA, and lymphocyte, monocyte, and platelet counts. HCC patients had lower lymphocyte and platelet counts and a higher monocyte count than the healthy controls (each p < 0.0001). HCC patients, and particularly those with a severe Child-Pugh class, had higher platelet counts than the corresponding cirrhosis patients (p = 0.003 and 0.002, respectively). HHV-8 seropositivity and antibody titers in HCC patients were comparable with values in cirrhosis patients and were much higher than in controls (both p < 0.0001). HCC patients, but not cirrhosis patients, had a higher prevalence of high anti-HHV-8 antibody titers (≥ 1:160) than healthy controls (p = 0.003). HCC patients with lymphopenia or thrombocytopenia had lower HHV-8 seropositivity than those without lymphopenia and thrombocytopenia (p = 0.04 and 0.01, respectively). One each of HCC and cirrhosis patients were positive for HHV-8 DNA. HCC patients seemed to suffer from less severe or shorter duration of portal hypertension compared with Child-Pugh class-matched cirrhosis patients. HCC patients had a high HHV-8 seroprevalence, which seemed to be inversely associated with lymphopenia and thrombocytopenia.


Assuntos
Carcinoma Hepatocelular/complicações , Infecções por Herpesviridae/epidemiologia , Herpesvirus Humano 8/imunologia , Adulto , Idoso , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos
5.
Anaesthesia ; 68(8): 851-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24044439

RESUMO

We compared direct laryngoscopy with a Macintosh blade vs indirect bronchoscopy with a Trachway® stylet, for endobronchial intubation with a left-sided double-lumen tube. We allocated participants scheduled for thoracic surgery and who had normal predicted laryngoscopy, 30 to each group. The mean (SD) intubation times with laryngoscope and Trachway were 48 (11) s vs 28 (4) s, respectively, p < 0.001. The rates of hoarseness on the first postoperative day, categorised as none/mild/moderate/severe, were 10/12/7/1 and 22/6/2/0, respectively, p = 0.008, without differences on subsequent days. Left endobronchial intubation with a double-lumen tube is slower using direct laryngoscopy and causes more hoarseness than indirect bronchoscopy with a Trachway stylet.


Assuntos
Intubação Intratraqueal/métodos , Laringoscópios , Laringoscopia/métodos , Adulto , Anestesia por Inalação , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Rouquidão/epidemiologia , Rouquidão/etiologia , Humanos , Masculino , Éteres Metílicos , Pessoa de Meia-Idade , Monitorização Intraoperatória , Faringite/epidemiologia , Faringite/etiologia , Complicações Pós-Operatórias/epidemiologia , Sevoflurano , Gravação em Vídeo
6.
Tissue Antigens ; 80(5): 424-30, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22931407

RESUMO

To investigate the relationship between human leukocyte antigen (HLA) class I and II alleles and treatment-induced anemia in chronic hepatitis C (CHC) patients receiving combination therapy with pegylated interferon-α (PEG-IFN-α) and ribavirin (RBV). One hundred six naïve CHC patients (59 females and 47 males; mean age, 53.08 years) who underwent combination treatment were enrolled. The patients were considered positive for hemoglobin (Hb)-related side effects if the Hb concentrations dropped below 10 g/dl during PEG-IFN-α plus RBV treatment. The HLA-A, -B, -C, -DR, and -DQ loci were investigated by sequence-based genotyping. The effects of the clinical characteristics, virologic variables, and the HLA alleles on treatment-induced anemia were evaluated by a logistic regression analysis. Forty patients (37.7%) had Hb levels below 10 g/dl during the treatment course. Low baseline Hb levels and an advanced liver fibrosis stage were associated with decreases in Hb levels to below 10 g/dl. The occurrence of treatment-related anemia (Hb < 10 g/dl) was significantly associated with HLA-B*15:02 as shown by multivariate analysis (adjusted odds ratio, 8.13; 95% confidence interval: 1.19-55.70; P-value after Holm's procedure, 0.03). HLA-B*15:02 is associated with treatment-induced anemia in Taiwanese CHC patients receiving combination therapy with PEG-IFN-α plus RBV.


Assuntos
Anemia/genética , Antivirais/efeitos adversos , Antígeno HLA-B15/genética , Hepatite C Crônica/genética , Interferon-alfa/efeitos adversos , Cirrose Hepática/genética , Polietilenoglicóis/efeitos adversos , Ribavirina/efeitos adversos , Adulto , Idoso , Anemia/induzido quimicamente , Anemia/imunologia , Anemia/virologia , Antivirais/administração & dosagem , Quimioterapia Combinada/efeitos adversos , Feminino , Genótipo , Antígeno HLA-B15/imunologia , Hemoglobinas/análise , Hepacivirus/efeitos dos fármacos , Hepacivirus/fisiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Teste de Histocompatibilidade , Humanos , Interferon-alfa/administração & dosagem , Cirrose Hepática/etiologia , Cirrose Hepática/imunologia , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Ribavirina/administração & dosagem , Análise de Sequência de DNA
7.
Anaesthesia ; 67(4): 411-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22324297

RESUMO

Intubation with a double-lumen tube is important for achieving one-lung ventilation and facilitating thoracic surgery. The GlideScope(®) videolaryngoscope (Verathon Inc., Bothell, WA, USA) is designed to assist tracheal intubation for patients with a difficult airway. We wished to compare the GlideScope and direct laryngoscopy for double-lumen tube intubation. Sixty adult patients requiring a double-lumen tube for thoracic surgery and predicted uncomplicated laryngoscopy were randomly assigned to a direct Macintosh laryngoscopy group (n = 30) or a GlideScope group (n = 30). The mean (SD) duration of intubation was longer in the Macintosh group (62.5 (29.7) s) than in the GlideScope group (45.6 (10.7) s; p = 0.007). There was no difference in the success of the first attempt at intubation (26/30 (87%) and 30/30 (100%) for Macintosh and GlideScope groups, respectively; p = 0.112). The incidence of sore throat and hoarseness was higher in the Macintosh group (18 (60%) and 14 (47%), respectively) than in the GlideScope group (6 (20%) and 4 (13%), respectively; p = 0.003 and 0.004). We conclude that double-lumen tube intubation in patients with predicted normal laryngoscopy is easier using the GlideScope videolaryngoscope than the Macintosh laryngoscope.


Assuntos
Intubação Intratraqueal/instrumentação , Laringoscópios , Laringoscopia/instrumentação , Gravação em Vídeo , Adulto , Desenho de Equipamento , Feminino , Humanos , Masculino
9.
Eur J Neurol ; 17(7): 945-50, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20136650

RESUMO

BACKGROUND AND PURPOSE: Risk-stratification models based on patient and disease characteristics are useful for aiding clinical decisions and for comparing the quality of care between different physicians or hospitals. In addition, prediction of mortality is beneficial for optimizing resource utilization. We evaluated the accuracy and discriminating power of the random forest (RF) to predict 30-day mortality of spontaneous intracerebral hemorrhage (SICH). METHODS: We retrospectively studied 423 patients admitted to the Taichung Veterans General Hospital who were diagnosed with spontaneous SICH within 24 h of stroke onset. The initial evaluation data of the patients were used to train the RF model. Areas under the receiver operating characteristic curves (AUC) were used to quantify the predictive performance. The performance of the RF model was compared to that of an artificial neural network (ANN), support vector machine (SVM), logistic regression model, and the ICH score. RESULTS: The RF had an overall accuracy of 78.5% for predicting the mortality of patients with SICH. The sensitivity was 79.0%, and the specificity was 78.4%. The AUCs were as follows: RF, 0.87 (0.84-0.90); ANN, 0.81 (0.77-0.85); SVM, 0.79 (0.75-0.83); logistic regression, 0.78 (0.74-0.82); and ICH score, 0.72 (0.68-0.76). The discriminatory power of RF was superior to that of the other prediction models. CONCLUSIONS: The RF provided the best predictive performance amongst all of the tested models. We believe that the RF is a suitable tool for clinicians to use in predicting the 30-day mortality of patients after SICH.


Assuntos
Inteligência Artificial , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/mortalidade , Sistemas de Apoio a Decisões Clínicas/tendências , Idoso , Algoritmos , Hemorragia Cerebral/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Medição de Risco/métodos , Sensibilidade e Especificidade
10.
Science ; 254(5034): 1003-6, 1991 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1948069

RESUMO

Crystallization of macromolecules for structural studies has long been a hit-or-miss process. The crystallization of hexanucleotides as Z-DNA was studied, and it was shown that the cation concentration for crystal formation could be predicted from solvation free energy (SFE) calculations. Solution studies on the conformation and solubilities of the hexanucleotides showed that a critical concentration of the DNA in the Z-conformation must be present in solution to effect crystallization. The SFE calculations therefore predict the propensity of the hexanucleotides to adopt the left-handed conformation and the driving force required to reach this critical concentration relative to the intrinsic solubility of Z-DNA for crystallization.


Assuntos
DNA/química , Oligodesoxirribonucleotídeos/química , Sequência de Bases , Cátions , Cristalografia , DNA/ultraestrutura , Modelos Moleculares , Conformação de Ácido Nucleico , Espectrofotometria Ultravioleta
13.
QJM ; 112(11): 841-846, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31286139

RESUMO

BACKGROUND: The relationship between gout medication use and cataract development is controversial. Moreover, limited clinical studies have evaluated this relationship. AIM: To assess the effects of colchicine, allopurinol and benzbromarone on the risk of cataract in patients with gout. DESIGN: Population-based nested case-control study. METHODS: We enrolled 7900 patients who had received a new diagnosis of cataract >3 years after gout diagnosis into the study group and 33 475 patients who did not receive a diagnosis of cataract into the control group by matching for age, sex and the year of gout diagnosis at a ratio of 1:1. We used World Health Organization's defined daily dose (DDD) as a measure to assess the dosage of colchicine, allopurinol and benzbromarone exposure. Logistic regression was used to estimate crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the risk of cataract. RESULTS: The risk of cataract significantly increased in patients who received colchicine at a cumulative DDD of ≥66.5 (OR = 1.17, 95% CI = 1.01-1.36, P = 0.041). In the age-stratified analysis, patients with gout aged >60 years had a higher risk of cataract (OR = 1.27, 95% CI = 1.06-1.53, P = 0.011) than did patients aged <60 years. Allopurinol and benzbromarone had no association with cataract. CONCLUSIONS: In this population-based nested case-control study, we observed that colchicine use increased the risk of cataract in patients with gout, especially in those aged >60 years who received colchicine at a cumulative DDD of >66.5.


Assuntos
Catarata/induzido quimicamente , Colchicina/efeitos adversos , Supressores da Gota/efeitos adversos , Gota/tratamento farmacológico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Alopurinol/uso terapêutico , Benzobromarona/uso terapêutico , Estudos de Casos e Controles , Catarata/epidemiologia , Colchicina/administração & dosagem , Bases de Dados Factuais , Feminino , Gota/complicações , Supressores da Gota/administração & dosagem , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Fatores de Risco , Taiwan , Adulto Jovem
14.
Mol Cell Biol ; 17(12): 7008-18, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9372932

RESUMO

The CCAAT-binding factor is an evolutionarily conserved heteromeric transcription factor that binds to CCAAT box-containing upstream activation sites within the promoters of numerous eukaryotic genes. The CCAAT-binding factor from Saccharomyces cerevisiae is a heterotetramer that contains the subunits Hap2p, Hap3p, Hap4p, and Hap5p and that functions in the activation of genes involved in respiratory metabolism. Here we describe the isolation of the cDNA encoding the Schizosaccharomyces pombe homolog of Hap5p, designated php5+. We have shown that Php5p is a subunit of the CCAAT-binding factor in fission yeast and is required for transcription of the S. pombe cyc1+ gene. Analysis of the evolutionarily conserved regions of Hap5p, Php5p, and the mammalian homolog CBF-C revealed two essential domains within Hap5p that are required for DNA binding and transcriptional activation. One is an 87-amino-acid core domain that is conserved among Hap5p, Php5p, and CBF-C and that is required for the assembly of the Hap2p-Hap3p-Hap5p heterotrimer both in vitro and in vivo. A second domain that is essential for the recruitment of Hap4p into the CCAAT-binding complex was identified in Hap5p and Php5p.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Proteínas Estimuladoras de Ligação a CCAAT , Sequência Conservada , Primers do DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dimerização , Evolução Molecular , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Dados de Sequência Molecular , Mutação , Reação em Cadeia da Polimerase , Conformação Proteica , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Transcrição Gênica
15.
Biosens Bioelectron ; 21(8): 1631-7, 2006 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16343891

RESUMO

In clinical practices, the examination of pentamer C-reactive protein (pCRP) is commonly used as a prognostic indicator of the risk of a patient developing cardiovascular disease (CVD). Structural modification of pCRP produces a modified CRP (mCRP) which exhibits different biological activities in the body. In recent years, mCRP has come to be regarded as a more powerful inducer than pCRP, and hence mCRP measurement has emerged as an important indicator for assessing the risk of developing CVD. The surface plasmon resonance (SPR) biosensing technique can be employed to increase the detection accuracy and real-time response when sensing pCRP or mCRP. In this study, three monoclonal antibodies (Mabs), C8, 8D8, and 9C9, are immobilized on a protein G layer for subsequent CRP detection. The experimental results reveal that the Mab C8 reacts with both pCRP and mCRP, the Mab 8D8 with pCRP, and the Mab 9C9 with mCRP. No false signals caused by non-specific binding are observed. When detecting pCRP using Mab C8, the SPR bioassay provides sufficient sensitivity to evaluate whether or not a patient is at risk of developing CVD. SPR biosensing provides a viable and accurate approach for the real-time evaluation of pCRP and mCRP levels, and is therefore of considerable benefit in clinical examinations of CPR.


Assuntos
Anticorpos Monoclonais/análise , Técnicas Biossensoriais/instrumentação , Proteína C-Reativa/análise , Imunoensaio/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Anticorpos Monoclonais/imunologia , Técnicas Biossensoriais/métodos , Proteína C-Reativa/imunologia , Desenho de Equipamento , Análise de Falha de Equipamento , Imunoensaio/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ressonância de Plasmônio de Superfície/métodos
18.
J Neurosci ; 21(16): 6430-9, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11487667

RESUMO

Neurons in the basal ganglia output nuclei display rhythmic burst firing after chronic nigrostriatal lesions. The thalamocortical network is a strong endogenous generator of oscillatory activity, and the striatum receives a massive projection from the cerebral cortex. Actually, the membrane potential of striatal projection neurons displays periodic shifts between a very negative resting potential (down state) and depolarizing plateaus (up states) during which they can fire action potentials. We hypothesized that an increased excitability of striatal neurons may allow transmission of cortical slow rhythms through the striatum to the remaining basal ganglia in experimental parkinsonism. In vivo intracellular recordings revealed that striatal projection neurons from rats with chronic nigrostriatal lesions had a more depolarized membrane potential during both the down and up states and an increased firing probability during the up events. Furthermore, lesioned rats had significantly fewer silent neurons than control rats. Simultaneous recordings of the frontal electrocorticogram and membrane potential of striatal projection neurons revealed that the signals were oscillating synchronously in the frequency range 0.4-2 Hz, both in control rats and rats with chronic nigrostriatal lesions. Spreading of the slow cortical rhythm is limited by the very low firing probability of control rat neurons, but a slow oscillation is well reflected in spike trains of approximately 60% of lesioned rat neurons. These findings provide in vivo evidence for a role of dopamine in controlling the flow of cortical activity through the striatum and may be of outstanding relevance for understanding the pathophysiology of Parkinson's disease.


Assuntos
Relógios Biológicos , Córtex Cerebral/fisiopatologia , Potenciais da Membrana , Neurônios , Doença de Parkinson Secundária/fisiopatologia , Potenciais de Ação , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/patologia , Corpo Estriado/fisiopatologia , Estimulação Elétrica , Lobo Frontal/fisiopatologia , Masculino , Neurônios/fisiologia , Oxidopamina , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/patologia , Periodicidade , Ratos , Ratos Sprague-Dawley , Tempo de Reação , Processamento de Sinais Assistido por Computador , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Substância Negra/fisiopatologia
19.
Circulation ; 104(13): 1519-25, 2001 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-11571246

RESUMO

BACKGROUND: Increasing evidence supports the role of heme oxygenase-1 (HO-1) in cytoprotective response and iron homeostasis. The object of this study was to investigate whether adenovirus-mediated gene transfer of HO-1 in arteries reduces iron overload and inhibits lesion formation in apolipoprotein E (apoE)-deficient mice. METHODS AND RESULTS: Infection of rat aortic smooth muscle cells with adenovirus carrying the human HO-1 gene (Adv-HO-1) resulted in a high-level expression of HO-1 protein, which effectively reduced the hemin-induced iron overload in these cells. Adenovirus-mediated gene transfer in arteries in vivo was achieved by direct injection of Adv-HO-1 into the left ventricles of anesthetized animals. Transgene was expressed in the endothelium and aortic lesion of apoE-deficient mice after they had received recombinant adenovirus for 1 week and gradually decayed during the next 5 weeks. When young apoE-deficient mice (14 weeks old) received Adv-HO-1 (2.5 x 10(9) pfu) for 6 weeks, lesions that developed in the aortic root or aortic arch were significantly smaller than those in control littermates receiving empty viral vector. Furthermore, the iron deposition as well as tissue iron content was much less in aortic tissue of Adv-HO-1-treated mice. The inhibitory effect of HO-1 gene transfer on the progression of advanced lesions was also observed in older apoE-deficient mice (20 weeks old) receiving Adv-HO-1 intraventricularly. CONCLUSIONS: Overexpression of HO-1 in vascular cells facilitates iron metabolism and attenuates development of atherosclerosis in apoE-deficient mice.


Assuntos
Apolipoproteínas E/metabolismo , Arteriosclerose/prevenção & controle , Heme Oxigenase (Desciclizante)/uso terapêutico , Adenoviridae/genética , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Artérias/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Expressão Gênica , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos , Heme Oxigenase (Desciclizante)/genética , Heme Oxigenase-1 , Injeções Intraventriculares , Ferro/farmacologia , Fígado/efeitos dos fármacos , Fígado/patologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso/enzimologia , Músculo Liso/metabolismo , Ratos , Ratos Sprague-Dawley
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