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1.
Eur J Dent Educ ; 22(1): e131-e141, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28504872

RESUMO

OBJECTIVE: To compare the perceptions of students and teachers of the "Educational Climate" (EC) in Spanish public dental schools. METHODS: A group of 1064 students and 354 teachers from six Spanish public dental schools responded to the DREEM questionnaire. This has 50 items grouped into five subscales: perception of learning (Learning); perception of teachers (Teachers); academic self-perceptions (Academic); perception of the atmosphere in the faculty (Atmosphere); and social self-perceptions (Social). The DREEM scale provides results for each item, each subscale and the overall EC. RESULTS: The EC scores were 123.2 (61.6%) for the students and 134.1 (67.0%) for the teachers (P<.001). The scores of the students and teachers for the subscales were, respectively: 27.9 (58.1%) and 30.2 (63.0 %) for Learning (P<.001); 26.8 (60.9%) and 32.6 (74.1%) for Teachers (P<.001); 20.7 (64.7%) and 20.5 (64.0%) for Academic (P=.333); 29.9 (62.3%) and 33.7 (70.3%) for Atmosphere (P<.001); and 17.9 (64.0%) and 16.9 (60.5%) for Social (P<.001). The students identified six problematic items (12.0 %) compared to only two (4.0 %) highlighted by the teachers. CONCLUSION: The students and teachers considered the EC to be "more positive than negative" in Spanish public dental schools; and the different subscales to be "positive and acceptable." The teachers did, however, evaluate the EC, and specifically the learning-teaching process, more positively than their students, identifying fewer problematic educational aspects. Both groups agreed on the need to: improve support systems for students who suffer from stress and reduce teaching based on "factual learning."


Assuntos
Atitude , Educação em Odontologia , Docentes de Odontologia/psicologia , Faculdades de Odontologia , Meio Social , Estudantes de Odontologia/psicologia , Autorrelato , Espanha
2.
J Neurol Sci ; 373: 210-215, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28131190

RESUMO

BACKGROUND AND OBJECTIVE: To study what comorbid conditions were present at baseline and 3years later in a cohort of Spanish Parkinson's disease (PD) patients, to compare comorbidity with both Alzheimer's disease (AD) and control groups and to analyze the role of comorbidity as predictor of mortality. METHODS: One hundred and forty-seven non-demented PD patients (57.1% males; 70.9±8.6years old) were included in this 36months follow-up (2012-2015), monocenter, evaluation study. The International Classification of Diseases, Tenth Revision (ICD-10), Charlson Index (CI), Comorbidity-Polypharmacy Score (CPS) and Elixhauser Comorbidity Measure (ECM) were used to assess comorbidity at baseline and at 3years. Forty-four AD patients and 44 control subjects were included as comparator groups. RESULTS: Total number of comorbidities (ICD-10) and polypharmacy at baseline were higher in PD and AD patients than controls (4.4±2.3 vs 5.2±2.4 vs 3.4±1.9 [p=0.001] and 81.6% vs 75% vs 56.8% [p=0.003], respectively). Diseases of the circulatory system (ICD-10/chapter-IX) and endocrine, nutritional and metabolic diseases (ICD-10/chapter-IV) were the most frequent in all groups. There was a significant increase in comorbidity (mean, +1.6±2.8) in all groups (p<0.0001) without differences between them. Seventeen patients died and 8 cases were did not follow-up. Comorbidity was a predictor of death in PD patients after adjust for other covariates (including age, sex, disease duration, disease stage, motor status and non-motor symptoms): ICD-10 (total number of comorbidities), hazard ratio 1.285 (95% confidence interval, 1.047-1.577; p=0.017); CI, hazard ratio 1.462 (95% confidence interval, 1.045-2.047; p=0.027). CONCLUSIONS: Comorbidity is frequent in PD patients, increases significantly over time and predicts mortality.


Assuntos
Doença de Alzheimer/epidemiologia , Doença de Parkinson/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/tratamento farmacológico , Comorbidade , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Morbidade , Doença de Parkinson/tratamento farmacológico , Polimedicação , Prognóstico , Estudos Retrospectivos , Espanha/epidemiologia
3.
Eur J Dent Educ ; 18(3): 162-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24330078

RESUMO

AIM: To carry out a psychometric evaluation of the Spanish-language version of the Dundee Ready Education Environment Measure (DREEM) applied to dental students. METHODS: A total of 1,391 students from nine Spanish public schools of dentistry responded to the DREEM questionnaire. To analyse the reliability of the DREEM questionnaire, the internal consistency was assessed and a 'test-retest' carried out. Validity was evaluated through analysis of item response rate, floor and ceiling effects, corrected item-total and item-subscale correlations and factor structure. A confirmatory factor analysis was performed to analyse the structure of the original DREEM scale. RESULTS: Cronbach's alpha coefficient for the 'Educational Climate' (EC) global scale was 0.92. In the subscales, the 'observed' Cronbach's alpha coefficients ranged between 0.57 and 0.79 and were higher than the 'expected' ones; except for the Social subscale. In the DREEM questionnaire, all of the corrected correlation coefficients between the items and the EC global scale, and the items and their corresponding subscales, were >0.2; except for items 50 and 17. All goodness-of-fit indices of confirmatory factor analysis showed acceptable values (close to one or zero, depending on the case), and there was consistency in the results. CONCLUSIONS: The Spanish-language version of the DREEM questionnaire is a reliable and valid instrument for analysing the EC for dental students and its factor structure is supported by the data. Although our findings indicate that the DREEM may be as culturally independent as was originally stated, more research should be directed at verifying the factor structure in various languages and cultural environments.


Assuntos
Atitude do Pessoal de Saúde , Educação em Odontologia , Psicometria , Meio Social , Estudantes de Odontologia/psicologia , Inquéritos e Questionários , Currículo , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Espanha
4.
Neurologia ; 25(5): 300-8, 2010 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-20643040

RESUMO

BACKGROUND AND OBJECTIVE: Although atypical antipsychotics (AA) provoke fewer extra-pyramidal symptoms (ES) than classic antipsychotics, their use in patients greater than or equal to 75 years old with dementia must be under compassionate-use. This is an important limitation. We performed a descriptive analysis of the use of atypical antipsychotics under compassionate-use (AACU) in the Ferrol health area. PATIENTS AND METHODS: We retrospectively assessed all the patients who were receiving an AACU from March, 2004 (that is the date when prescription under compassionate-use of AA came into force in Spain) to November 30, 2008. RESULTS: One hundred and thirty-three of 164 patients (63.6% women; median ages, 81.9 ± 4.95 years) were included. Diagnostic aetiologies were: 42.9% Alzheimer's disease, 30.8% Parkinson-dementia/Lewy body disease, and 15.8% vascular/mixed dementia. A total of 68.4% of patients had received other anti-psychotic drugs previously and 32.3% had ES due to antipsychotics. The AACU received were: quetiapine (76.7%), ziprasidone (18.8%), and olanzapine (4.5%). Median follow-up time was 20.25 ± 20.38 months. Side effects were observed in 19.7% of patients. Improvement of NPI (Neuropsychiatric Inventory) was 33.3 ± 24.75 points. Agitation/aggressiveness (5.6 ± 4.55), delirious ideas (4.94 ± 5.07), irritability (4.38 ± 4.94), and anxiety (4.32 ± 4.83) were the symptoms that most improved. Although there were no differences between AACU, quetiapine was associated with significant maintenance in monotherapy (94.1% vs 72% for ziprasidone and 83.3% for olanzapine; p < 0.0001). CONCLUSIONS: AACU are effective and well tolerated drugs. Quetiapine was the most frequently used AACU. An excessive percentage of patients previously received other antipsychotics and present with ES.


Assuntos
Antipsicóticos/uso terapêutico , Ensaios de Uso Compassivo , Demência/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Benzodiazepinas/uso terapêutico , Dibenzotiazepinas/uso terapêutico , Feminino , Humanos , Olanzapina , Piperazinas/uso terapêutico , Fumarato de Quetiapina , Estudos Retrospectivos , Espanha , Tiazóis/uso terapêutico , Resultado do Tratamento
5.
Neurología (Barc., Ed. impr.) ; 25(5): 300-308, jul. 2010. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-94727

RESUMO

Objetivos: Aunque quetiapina y ziprasidona producen menos síntomas extrapiramidales (SEP) que otros antipsicóticos, su uso en pacientes mayores de 75 años con demencia se ve condicionado por la obligatoriedad de prescribirlos “por uso compasivo”. Realizamos un análisis descriptivo del uso de antipsicóticos atípicos de uso compasivo (AAUC) en el área sanitaria de Ferrol. Pacientes y métodos: Incluimos a todos los pacientes que recibieran un AAUC desde marzo de 2004 (fecha en que entró en vigor la dispensación de AAUC) hasta el 30-11-2008. Resultados: Se incluyó a 133 de un total de 164 pacientes (el 63,6%, mujeres; media±desviación estándar de edad, 81,9±4,95 años). El 94,1% presentaba demencia (el 42,9%, enfermedad de Alzheimer; el 30,8%, demencia-enfermedad de Parkinson, y el 15,8%, demencia vascular/mixta). El 68,4% había recibido algún otro antipsicótico previo y el 32,3% presentaba SEP secundarios. Los AAUC prescritos fueron: quetiapina (76,7%), ziprasidona (18,8%) y olanzapina (4,5%). La media de tiempo de seguimiento fue 20,25±20,38 meses. El cumplimiento terapéutico fue del 95,5%. El 19,7% presentó efectos secundarios. La media de mejora en la escala NPI (Neuropsychiatric Inventory) fue 33,3±24,75 puntos. La agitación/agresividad (5,6±4,55), las ideas delirantes (4,94±5,07), la irritabilidad (4,38±4,94) y la ansiedad (4,32±4,83) fueron los síntomas que más mejoraron. Aunque no hubo diferencias entre los 3 AAUC, quetiapina conllevó un mayor mantenimiento en monoterapia (el 94,1 frente al 72% de ziprasidona y el 83,3% de olanzapina; p<0,0001). Conclusiones: Los AAUC son fármacos efectivos y bien tolerados. Quetiapina es el AAUC más utilizado. Un porcentaje excesivo de pacientes reciben antes otros antipsicóticos y presentan SEP (AU)


Background and objective: Although atypical antipsychotics (AA) provoke fewer extra-pyramidal symptoms (ES) than classic antipsychotics, their use in patients greater than or equal to 75 years old with dementia must be under compassionate-use. This is an important limitation. We performed a descriptive analysis of the use of atypical antipsychotics under compassionate-use (AACU) in the Ferrol health area.Patients and methods: We retrospectively assessed all the patients who were receiving an AACU from March, 2004 (that is the date when prescription under compassionate-use of AA came into force in Spain) to November 30, 2008. Results: One hundred and thirty-three of 164 patients (63.6% women; median ages, 81.9 ± 4.95 years) were included. Diagnostic aetiologies were: 42.9% Alzheimer's disease, 30.8% Parkinson-dementia/Lewy body disease, and 15.8% vascular/mixed dementia. A total of 68.4% of patients had received other anti-psychotic drugs previously and 32.3% had ES due to antipsychotics. The AACU received were: quetiapine (76.7%), ziprasidone (18.8%), and olanzapine (4.5%). Median follow-up time was 20.25 ± 20.38 months. Side effects were observed in 19.7% of patients. Improvement of NPI (Neuropsychiatric Inventory) was 33.3 ± 24.75 points. Agitation/aggressiveness (5.6 ± 4.55), delirious ideas (4.94 ± 5.07), irritability (4.38 ± 4.94), and anxiety (4.32 ± 4.83) were the symptoms that most improved. Although there were no differences between AACU, quetiapine was associated with significant maintenance in monotherapy (94.1% vs 72% for ziprasidone and 83.3% for olanzapine; p < 0.0001).Conclusions: AACU are effective and well tolerated drugs. Quetiapine was the most frequently used AACU. An excessive percentage of patients previously received other antipsychotics and present with ES (AU)


Assuntos
Humanos , Antipsicóticos/uso terapêutico , Demência/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Prescrições de Medicamentos/estatística & dados numéricos , Agitação Psicomotora/tratamento farmacológico , Transtornos Mentais/tratamento farmacológico , Doenças dos Gânglios da Base/induzido quimicamente
6.
Cephalalgia ; 22(4): 303-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12100093

RESUMO

The mechanism for headache in patients with acute ischaemic stroke are not completely understood. We analysed the relationship between headache and the early worsening of neurological symptoms in patients with acute ischaemic stroke, and we studied the possible biochemical mechanisms implicated. Headache at the onset of ischaemic stroke predicted progression with a sensitivity, specificity, and positive predictive value of 56%, 99%, and 98%, respectively. CSF concentrations of glutamate, Interleukin-6, and NO-m were significantly greater in patients with progressing stroke than in patients with nonprogressing stroke, and these biochemical markers were also significantly higher in patients with headache than in those without headache. Results of this study suggest that headache at the onset of ischaemic stroke is an independent predictor of neurological worsening and we hypothesize that headache might be a surrogate marker of the molecular mechanisms involved in neurological worsening after acute stroke.


Assuntos
Isquemia Encefálica/complicações , Cefaleia/etiologia , Doença Aguda , Idoso , Biomarcadores , Glicemia/análise , Isquemia Encefálica/líquido cefalorraquidiano , Isquemia Encefálica/fisiopatologia , Estudos de Coortes , Progressão da Doença , Feminino , Glutamatos/líquido cefalorraquidiano , Cefaleia/líquido cefalorraquidiano , Cefaleia/fisiopatologia , Humanos , Interleucina-6/líquido cefalorraquidiano , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Valor Preditivo dos Testes , Sensibilidade e Especificidade
7.
Br J Pharmacol ; 134(6): 1195-206, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11704639

RESUMO

1. Two sodium channel toxins, BgII and BgIII, have been isolated and purified from the sea anemone Bunodosoma granulifera. Combining different techniques, we have investigated the electrophysiological properties of these toxins. 2. We examined the effect of BgII and BgIII on rat ventricular strips. These toxins prolong action potentials with EC50 values of 60 and 660 nM and modify the resting potentials. 3. The effect on Na+ currents in rat cardiomyocytes was studied using the patch-clamp technique. BgII and BgIII slow the rapid inactivation process and increase the current density with EC50 values of 58 and 78 nM, respectively. 4. On the cloned hH1 cardiac Na+ channel expressed in Xenopus laevis oocytes, BgII and BgIII slow the inactivation process of Na+ currents (respective EC50 values of 0.38 and 7.8 microM), shift the steady-state activation and inactivation parameters to more positive potentials and the reversal potential to more negative potentials. 5. The amino acid sequences of these toxins are almost identical except for an asparagine at position 16 in BgII which is replaced by an aspartic acid in BgIII. In all experiments, BgII was more potent than BgIII suggesting that this conservative residue is important for the toxicity of sea anemone toxins. 6. We conclude that BgII and BgIII, generally known as neurotoxins, are also cardiotoxic and combine the classical effects of sea anemone Na+ channels toxins (slowing of inactivation kinetics, shift of steady-state activation and inactivation parameters) with a striking decrease on the ionic selectivity of Na+ channels.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Venenos de Cnidários/farmacologia , Coração/efeitos dos fármacos , Anêmonas-do-Mar/química , Canais de Sódio/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Clonagem Molecular , Venenos de Cnidários/isolamento & purificação , Relação Dose-Resposta a Droga , Ventrículos do Coração/citologia , Ventrículos do Coração/efeitos dos fármacos , Técnicas In Vitro , Modelos Biológicos , Dados de Sequência Molecular , Técnicas de Patch-Clamp , Ratos , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Função Ventricular , Xenopus laevis
8.
Toxicon ; 39(5): 693-702, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11072049

RESUMO

Five toxins (APE 1 to APE 5) of the sea anemone species Anthopleura elegantissima (Brandt) have been isolated from a toxic by-product fraction of its concentrated crude watery-methanolic extract, prepared previously for the isolation of a neuropeptide (the head-activator) by Schaller and Bodenmüller (Proc. Natl. Acad. Sci. USA 78 (1981) 7000) from 200kg sea anemones. Toxin purification was performed by desalting of the starting material by dialysis (MWCO 3500) against distilled water, anion exchange chromatography on QAE-Sephadex A25 at pH 8, twice gel filtration on Sephadex G50 m, repeated chromatography on QAE-Sephadex at pH 10 and chromatography on the cation exchanger Fractogel EMD SO(3)(-)-650 M.Final purification of the toxins was achieved by HPLC on MN SP 250/10 Nucleosil 500-5 C(18) PPN and MN SP 250/21 Nucleosil 300-7 C(18). Each toxin was composed of at least two isotoxins of which APE 1-1, APE 1-2, APE 2-1, APE 2-2 and APE 5-3 were isolated in preparative scale. With exception of APE 5-3 the sequences of the isotoxins have been elucidated. They resemble the 47 residue type-I long polypeptide toxins native to Anemonia sulcata (Pennant). All isotoxins paralyse the shore crab (Carcinus maenas) by tetanic contractions after i.m. application. The toxins modify current passing through the fast Na(+) channel in neuroblastoma cells, leading to delayed and incomplete inactivation. APE 1-1, APE 2-1 and APE 5-3 produce a positive inotropic effect in mammalian heart muscle, although they differ in potency. The order of potency is APE 2-1>APE 1-1>APE 5-3 (i.e. threshold concentrations are 1, 10 and 300nM, respectively). In addition, they enhance the spontaneous beating frequency in isolated right atria (guinea pig). The most potent cardiotoxic isotoxin is APE 2-1, its sequence is identical with that of AP-C, a toxin isolated and characterised previously by Norton et al. (Drugs and Foods from the Sea, 1978, University of Oklahoma Press, p. 37-50).LD50 APE 2-1:1 micro g/kg b.w. C. maenas (i.m.). LD50 APE 1-1:10 microg/kg b.w. C. maenas (i. m.). LD50 APE 5-3:50 microg/kg b.w. C. maenas (i.m.).


Assuntos
Venenos de Cnidários/isolamento & purificação , Venenos de Cnidários/toxicidade , Neurotoxinas/isolamento & purificação , Peptídeos/isolamento & purificação , Anêmonas-do-Mar , Animais , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Cobaias , Dose Letal Mediana , Masculino , Camundongos , Contração Miocárdica/efeitos dos fármacos , Técnicas de Patch-Clamp , Peptídeos/toxicidade , Canais de Sódio/efeitos dos fármacos
9.
Brain Res ; 864(2): 312-4, 2000 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-10802039

RESUMO

We studied the effects of BgK toxin on outward K(+) currents in isolated neurons of the snail Helix aspersa, using the whole cell patch clamp technique. BgK partially and reversibly blocked K(+) currents in the 1 pM to 100 nM concentration range (n=53). The dose-response curve for BgK current inhibition had a maximum blocking effect at 100 nM. Our results indicate that BgK is a potent, apparently non-selective, K(+) channel blocker in molluscan neurons.


Assuntos
Venenos de Cnidários/farmacologia , Neurônios/química , Neurônios/fisiologia , Bloqueadores dos Canais de Potássio , Animais , Relação Dose-Resposta a Droga , Caracois Helix , Potenciais da Membrana/efeitos dos fármacos , Técnicas de Patch-Clamp , Potássio/metabolismo , Canais de Potássio/fisiologia , Anêmonas-do-Mar
10.
Toxicon ; 35(12): 1699-709, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9481812

RESUMO

The effects were studied of a toxin (Bainh) isolated from the secretion of the Caribbean sea anemone Bunodosoma granulifera on electrical and mechanical activities of rat ventricular muscle. The effects on the ionic currents of single rat and dog ventricular cardiomyocytes were studied using the whole-cell recording patch-clamp technique. In the concentration range from 1 to 10 mg/ml, Bainh increased the force of contraction and induced an increase in action potential duration of ventricular multicellular preparations. In single cardiomyocytes, at concentrations up to 10 mg/ml Bainh showed no significant effects on the sodium current. However, at 0.5-1 mg/ml it increased the L-type Ca current (ICaL) by 25-50%. This increase in ICaL was not voltage dependent and was reversible after washout. The transient outward current was not significantly affected by Bainh (1-10 mg/ml). In this concentration range, Bainh markedly (approximately 75%) increased the inward-going rectifier current, IKI. This effect that was not voltage dependent and was fully reversible upon returning to control solution. It is suggested that these effects on ionic currents could explain the positive inotropic action of Bainh on cardiac multicellular preparations.


Assuntos
Coração/efeitos dos fármacos , Canais Iônicos/efeitos dos fármacos , Toxinas Marinhas/farmacologia , Contração Miocárdica/efeitos dos fármacos , Anêmonas-do-Mar/química , Potenciais de Ação/efeitos dos fármacos , Animais , Canais de Cálcio/efeitos dos fármacos , Células Cultivadas , Cães , Coração/fisiologia , Ventrículos do Coração/efeitos dos fármacos , Técnicas In Vitro , Toxinas Marinhas/isolamento & purificação , Técnicas de Patch-Clamp , Canais de Potássio/efeitos dos fármacos , Ratos , Canais de Sódio/efeitos dos fármacos , Estimulação Química , Função Ventricular
11.
Toxicon ; 34(11-12): 1361-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9027992

RESUMO

The sea anemone Anemonia sulcata is a well-known natural source of supply of biologically active polypeptides. So far, five toxins, ATX I, II, III, IV and AS V, several polyvalent protease inhibitors, an elastase inhibitor, two blood pressure-depressive polypeptides and very recently peptides that inhibit competitively the binding of 125I-dendrotoxin to rat brain membranes and block the voltage-sensitive K+ channels, have been isolated from it. The sea anemone toxins (especially toxin II of A. sulcata, ATX II) are very important tools in neurophysiological and pharmacological research, and their structure-function relationship has been investigated. Because of the great scientific value of the sea anemone toxins a simplification of their purification procedure was elaborated.


Assuntos
Venenos de Cnidários/isolamento & purificação , Peptídeos/isolamento & purificação , Anêmonas-do-Mar/química , Animais , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Peptídeos/análise
12.
Toxicon ; 34(4): 443-50, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8735243

RESUMO

In the search for new glutamate antagonists it seems promising to characterize the effects of venom from invertebrates that prey mainly on crustaceans. In this work, the exudate of the sea anemone Phyllactis flosculifera was used as a source of this type of compound. The action of chromatographic fraction D from P. flosculifera was tested upon microion-tophoretically evoked glutamate responses in intracellular recordings from central neurons of the land snail Zachrysia guanensis. Bath application of fraction D (2-8 mg/ml, n = 13) diminished both the excitatory and the inhibitory components of glutamate agonists in Z. guanensis neurons; this action was dose-dependent and partially reversible. Fraction D actions were also tested in the multiunit spontaneous and mechanically evoked responses of the glutamatergic junction between hair cells and afferent neurons of the axolotl Ambystoma tigrinum. Pressure ejection of fraction D in concentrations ranging from 0.5 to 2 mg/ml (n = 9) decreased the spontaneous and mechanically evoked activity of semicircular canal afferent neurons and the responses evoked by kainic acid and alpha-amino-3-hydroxy-5-methylisoxasole-4-propionic acid. This action was also dose-dependent and partially reversible. These results indicate that fraction D acts as a glutamate receptor antagonist in snail and amphibian neurons. Further studies are required to characterize the active compounds responsible for this action and its specificity upon the subtypes of glutamate receptors.


Assuntos
Venenos de Cnidários/toxicidade , Antagonistas de Aminoácidos Excitatórios/toxicidade , Neurônios Aferentes/efeitos dos fármacos , Anêmonas-do-Mar/metabolismo , Ambystoma , Animais , Fracionamento Químico , Cromatografia em Gel , Venenos de Cnidários/metabolismo , Cóclea/efeitos dos fármacos , Cóclea/metabolismo , Antagonistas de Aminoácidos Excitatórios/metabolismo , Iontoforese , Ácido Caínico/toxicidade , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/metabolismo , Neurônios Aferentes/citologia , Neurônios Aferentes/metabolismo , Ácido Quisquálico/toxicidade , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Caramujos , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/toxicidade
13.
Biochim Biophys Acta ; 1157(1): 86-92, 1993 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-8098956

RESUMO

A peptide toxin affecting potassium channels was isolated from the sea anemone Bunodosoma granulifera. It facilitates acetylcholine release at avian neuromuscular junctions, competes with dendrotoxin I, a probe for voltage-dependent potassium channels, for binding to synaptosomal membranes of rat brain with a Ki of 0.7 nM and suppresses K+ currents in rat dorsal root ganglion neurones in culture. It represents a new structural type of potassium channel toxin with the sequence V1RCDWFKETA10CRHAKSLGNC20RTSQKYRANC30AKTLQCC37 (M(r) 4275, three disulfides).


Assuntos
Venenos de Cnidários/isolamento & purificação , Canais de Potássio/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Células Cultivadas , Galinhas , Cromatografia em Gel , Cnidários , Venenos de Cnidários/química , Venenos de Cnidários/toxicidade , Espectrometria de Massas , Dados de Sequência Molecular , Junção Neuromuscular/efeitos dos fármacos , Ratos , Homologia de Sequência de Aminoácidos , Membranas Sinápticas/efeitos dos fármacos
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