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1.
Future Microbiol ; 17: 1133-1146, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35880557

RESUMO

Introduction: Candida krusei and Candida albicans are biofilm-forming drug-resistant yeasts that cause bloodstream infections that can lead to death. Materials & methods: nystatin and itraconazole were combined with two synthetic peptides, PepGAT and PepKAA, to evaluate the synergistic effect against Candida biofilms. Additionally, scanning electron and fluorescence microscopies were employed to understand the mechanism behind the synergistic activity. Results: Peptides enhanced the action of drugs to inhibit the biofilm formation of C. krusei and C. albicans and the degradation of mature biofilms of C. krusei. In combination with antifungal drugs, peptides' mechanism of action involved cell wall and membrane damage and overproduction of reactive oxygen species. Additionally, in combination, the peptides reduced the toxicity of drugs to red blood cells. Conclusion: These results reveal that the synthetic peptides enhanced the antibiofilm activity of drugs, in addition to reducing their toxicity. Thus, these peptides have strong potential as adjuvants and to decrease the toxicity of drugs.


Candida krusei and Candida albicans are biofilm-forming, drug-resistant yeasts that cause bloodstream infections that can lead to death. In this study, biofilms of C. krusei and C. albicans were treated with a solution composed of synthetic peptides and antifungal drugs, none of which were effective alone. The synthetic peptides reduced the toxicity of drugs to red blood cells. These results may pave the way to the application of synthetic peptides as a beneficial additional to antifungal drugs to treat fungi that cannot be killed by drugs alone.


Assuntos
Antifúngicos , Candida , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Biofilmes , Candida albicans , Testes de Sensibilidade Microbiana , Peptídeos/farmacologia
2.
Int J Biol Macromol ; 208: 105-125, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35300999

RESUMO

Late in 2019, SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) emerged, causing an unknown type of pneumonia today called coronaviruses disease 2019 (COVID-19). COVID-19 is still an ongoing global outbreak that has claimed and threatened many lives worldwide. Along with the fastest vaccine developed in history to fight SARS-CoV-2 came a critical problem, SARS-CoV-2. These new variants are a result of the accumulation of mutations in the sequence and structure of spike (S) glycoprotein, which is by far the most critical protein for SARS-CoV-2 to recognize cells and escape the immune system, in addition to playing a role in SARS-CoV-2 infection, pathogenicity, transmission, and evolution. In this review, we discuss mutation of S protein and how these mutations have led to new variants that are usually more transmissible and can thus mitigate the immunity produced by vaccination. Here, analysis of S protein sequences and structures from variants point out the mutations among them, how they emerge, and the behavior of S protein from each variant. This review brings details in an understandable way about how the variants of SARS-CoV-2 are a result of mutations in S protein, making them more transmissible and even more aggressive than their relatives.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Glicoproteínas/genética , Humanos , Mutação , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
3.
Pediatr Pulmonol ; 53(4): 517-525, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29393599

RESUMO

OBJECTIVE: The identification of oropharyngeal aspiration is paramount since it can have negative consequences on a compromised respiratory status. Our hypothesis was that dysphagia in neurologically intact children with respiratory disease is associated to specific clinical markers. STUDY DESIGN: Using the medical files we conducted a retrospective, observational cohort study on children admitted to the pediatric hospital unit due to respiratory disease. We collected data on specific parameters of a clinical swallowing assessment and dysphagia was classified according to the Dysphagia Management Staging Scale. We also included the following clinical markers: age, days of hospitalization, need for orotracheal intubation (OTI), duration of orotracheal intubation (in hours), number of previous hospital admissions due to respiratory disease, number of previous hospital admissions due to other causes, and previous orotracheal intubations. RESULTS: The final study sample consisted of 102 patients (mean age of 5.88 months). For the purposes of statistical analysis, the patients were grouped according to the classification of dysphagia (ie, no dysphagia, mild dysphagia, and moderate-severe dysphagia). Data analysis indicated that the clinical markers of orotracheal intubation (P = 0.042), duration of orotracheal intubation (P = 0.025), and days of hospitalization (P = 0.037) were significant in children with moderate-severe dysphagia. CONCLUSIONS: Our data indicate that neurologically intact children with respiratory disease who were submitted to prolonged OTI (ie, over 48 h) should be prioritized for receiving a detailed swallowing assessment.


Assuntos
Transtornos de Deglutição/etiologia , Intubação Intratraqueal/efeitos adversos , Doenças Respiratórias/complicações , Pré-Escolar , Deglutição , Feminino , Hospitalização , Humanos , Lactente , Masculino , Doenças Respiratórias/terapia
4.
Clinics ; 72(12): 718-722, Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-890703

RESUMO

OBJECTIVES: To compare the videofluoroscopic findings of patients with suspected oropharyngeal dysphagia with the results of a clinical screening protocol. METHODS: A retrospective observational cohort study was conducted on all consecutive patients with suspected oropharyngeal dysphagia between March 2015 and February 2016 who were assigned to receive a videofluoroscopic assessment of swallowing. All patients were first submitted to videofluoroscopy and then to the clinical assessment of swallowing. The clinical assessment was performed within the first 24 hours after videofluoroscopy. The videofluoroscopy results were analyzed regarding penetration/aspiration using an 8-point multidimensional perceptual scale. The accuracy of the clinical protocol was analyzed using the sensitivity, specificity, likelihood ratios and predictive values. RESULTS: The selected sample consisted of 50 patients. The clinical protocol presented a sensitivity of 50% and specificity of 95%, with an accuracy of 88%. "Cough" and "wet-hoarse" vocal quality after/during swallowing were clinical indicators that appeared to correctly identify the presence of penetration/aspiration risk. CONCLUSION: The clinical protocol used in the present study is a simple, rapid and reliable clinical assessment. Despite the absence of a completely satisfactory result, especially in terms of the sensitivity and positive predictive values, we suggest that lower rates of pneumonia can be achieved using a formal dysphagia screening method.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/diagnóstico por imagem , Triagem/normas , Qualidade da Voz , Fluoroscopia/métodos , Protocolos Clínicos , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade
5.
Clinics (Sao Paulo) ; 72(12): 718-722, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29319716

RESUMO

OBJECTIVES: To compare the videofluoroscopic findings of patients with suspected oropharyngeal dysphagia with the results of a clinical screening protocol. METHODS: A retrospective observational cohort study was conducted on all consecutive patients with suspected oropharyngeal dysphagia between March 2015 and February 2016 who were assigned to receive a videofluoroscopic assessment of swallowing. All patients were first submitted to videofluoroscopy and then to the clinical assessment of swallowing. The clinical assessment was performed within the first 24 hours after videofluoroscopy. The videofluoroscopy results were analyzed regarding penetration/aspiration using an 8-point multidimensional perceptual scale. The accuracy of the clinical protocol was analyzed using the sensitivity, specificity, likelihood ratios and predictive values. RESULTS: The selected sample consisted of 50 patients. The clinical protocol presented a sensitivity of 50% and specificity of 95%, with an accuracy of 88%. "Cough" and "wet-hoarse" vocal quality after/during swallowing were clinical indicators that appeared to correctly identify the presence of penetration/aspiration risk. CONCLUSION: The clinical protocol used in the present study is a simple, rapid and reliable clinical assessment. Despite the absence of a completely satisfactory result, especially in terms of the sensitivity and positive predictive values, we suggest that lower rates of pneumonia can be achieved using a formal dysphagia screening method.


Assuntos
Transtornos de Deglutição/diagnóstico por imagem , Triagem/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos Clínicos , Feminino , Fluoroscopia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade , Qualidade da Voz
6.
J Pharm Pharmacol ; 68(1): 63-75, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26725912

RESUMO

OBJECTIVES: Our main objective was to investigate the mechanisms underlying the effects of hyperhomocysteinaemia (HHcy) on contractile response mediated by α1-adrenoceptors in the rat corpus cavernosum. METHODS: Concentration-response curves for phenylephrine (PE) were obtained in strips of corpus cavernosum, in absence or after incubation with tiron, tempol or polyethylene glycol (PEG)-catalase combined or not with tempol. We also measured the superoxide anion (O2(-)) and hydrogen peroxide (H2O2) generation, superoxide dismutase (SOD) and catalase activity and α-actin expression in rat corpus cavernosum from both groups. KEY FINDINGS: HHcy increased PE-induced contraction in cavernosal strips. Tiron, PEG-catalase or tempol increased PE-induced contraction in strips from control rats, but it was not altered by tiron or PEG-catalase in HHcy rats, whereas tempol reduced this response. The combination of PEG-catalase and tempol did not alter the contractile response to PE in both groups. HHcy increased O2(-) generation and SOD activity, whereas H2O2 concentration was reduced. Finally, HHcy did not alter catalase activity or expression of α-actin. CONCLUSIONS: The major new finding from this study is that HHcy induced a marked increase in PE-induced contraction in rat corpus cavernosum by a mechanism that involves increased O2(-) generation and it could play a role in the pathogenesis of erectile dysfunction associated with HHcy.


Assuntos
Hiper-Homocisteinemia/metabolismo , Pênis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores Adrenérgicos alfa 1/metabolismo , Actinas/metabolismo , Animais , Catalase/metabolismo , Disfunção Erétil/metabolismo , Peróxido de Hidrogênio/metabolismo , Masculino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Pênis/efeitos dos fármacos , Fenilefrina/farmacologia , Polietilenoglicóis/metabolismo , Ratos , Ratos Wistar , Superóxidos/metabolismo
7.
J Speech Lang Hear Res ; 55(4): 1097-111, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22232402

RESUMO

PURPOSE: In this study, the authors examined the comprehension of sentences with predicates and reflexives that are linked to a nonadjacent noun as a test of the hierarchical ordering deficit (HOD) hypothesis. That hypothesis and more modern versions posit that children with specific language impairment (SLI) have difficulty in establishing nonadjacent (hierarchical) relations among elements of a sentence. The authors also tested whether additional working memory demands in constructions containing reflexives affected the extent to which children with SLI incorrectly structure sentences as indicated by their picture-pointing comprehension responses. METHOD: Sixteen Brazilian Portuguese-speaking children (8;4-10;6 [years;months]) with SLI and 16 children with typical language development (TLD) matched for age (± 3 months), gender, and socioeconomic status participated in 2 experiments (predicate and reflexive interpretation). In the reflexive experiment, the authors also manipulated working memory demands. Each experiment involved a 4-choice picture selection sentence comprehension task. RESULTS: Children with SLI were significantly less accurate on all conditions. Both groups made more hierarchical syntactic construction errors in the long working memory condition than in the short working memory condition. CONCLUSION: The HOD hypothesis was not confirmed. For both groups, syntactic factors (structural assignment) were more vulnerable than lexical factors (prepositions) to working memory effects in sentence miscomprehension.


Assuntos
Linguagem Infantil , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Transtornos do Desenvolvimento da Linguagem/fisiopatologia , Memória de Curto Prazo/fisiologia , Semântica , Brasil , Criança , Compreensão/fisiologia , Feminino , Humanos , Testes de Inteligência , Testes de Linguagem , Masculino , Vocabulário
8.
In Vitro Cell Dev Biol Anim ; 47(10): 716-27, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22069028

RESUMO

Quiescin sulfhydryl oxidases (QSOXs) catalyze the formation of disulfide bonds in peptides and proteins, and in vertebrates comprise two proteins: QSOX1 and QSOX2. QSOX1, the most extensively studied type, has been implicated in protein folding, production of extracellular matrix, redox regulation, protection from apoptosis, angiogenesis, and cell differentiation. Atherosclerosis is an immunopathological condition in which redox processes, apoptosis, cell differentiation, and matrix secretion/maturation have critical roles. Considering these data, we hypothesized that QSOX1 could be involved in this disease, possibly reducing apoptosis and angiogenesis inside the plaque. QSOX1 labeling in normal human carotid vessels showed predominant expression by endothelium, subendothelium, and adventitia. In atherosclerotic plaques, however, QSOX1 was highly expressed in macrophages at the lipid core. QSOX1 expression was also studied in terms of mRNA and protein in cell types present in plaques under apoptotic or activating stimuli, emulating conditions found in the atherosclerotic process. QSOX1 mRNA increased in endothelial cells and macrophages after the induction of apoptosis. At the protein level, the correlation between apoptosis and QSOX1 expression was not evident in all cell types, possibly because of a rapid secretion of QSOX1. Our results propose for the first time possible roles for QSOX1 in atherosclerosis, being upregulated in endothelial cells and macrophages by apoptosis and cell activation, and possibly controlling these processes, as well as angiogenesis. The quantitative differences in QSOX1 induction may depend on the cell type and also on local factors.


Assuntos
Apoptose , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Placa Aterosclerótica/enzimologia , Placa Aterosclerótica/patologia , Angiotensina II/farmacologia , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Apoptose/efeitos dos fármacos , Western Blotting , Brefeldina A/farmacologia , Camptotecina/farmacologia , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/enzimologia , Artérias Carótidas/patologia , Diferenciação Celular/efeitos dos fármacos , Células HeLa , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imuno-Histoquímica
9.
J Pediatr (Rio J) ; 87(5): 412-8, 2011.
Artigo em Inglês, Português | MEDLINE | ID: mdl-22012342

RESUMO

OBJECTIVES: To assess the frequency of hospitalizations and emergency department visits of children and adolescents before and after the enrollment in an asthma program. METHODS: Medical records of 608 asthmatics younger than 15 years were assessed retrospectively. The frequency of hospitalizations and emergency department visits caused by exacerbations were evaluated before and after enrollment in an asthma program. Patients were treated with medications and a wide prophylactic management program based on the Global Initiative for Asthma (GINA). The before asthma program (BAP) period included 12 months before enrollment, whereas the after asthma program (AAP) period ranged from 12 to 56 months after enrollment. RESULTS: In the BAP period, there were 895 hospitalizations and 5,375 emergency department visits, whereas in the AAP period, there were 180 and 713, respectively. This decrease was significant in all statistical analyses (p = 0.000). CONCLUSIONS: Compliance with the GINA recommendations led to a significant decrease in the frequency of hospitalizations and emergency department visits in children and adolescents with asthma.


Assuntos
Asma/prevenção & controle , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Programas Nacionais de Saúde/normas , Adolescente , Asma/terapia , Brasil , Criança , Pré-Escolar , Métodos Epidemiológicos , Feminino , Fidelidade a Diretrizes/normas , Humanos , Lactente , Masculino , Guias de Prática Clínica como Assunto , Avaliação de Programas e Projetos de Saúde , Fatores de Tempo
10.
Folia Phoniatr Logop ; 62(5): 223-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20639638

RESUMO

Diversity is one of the major characteristics of Brazil and all South America. This paper presents an overview of the current situation of the education of speech and language pathologists (SLP) and audiologists in Brazil and in several other countries of South America. This paper also discusses the main challenges shared by these countries. The discussion is focused on the mutual interferences between education and the areas of professional practice, cultural diversity and continued education. There are many emerging issues about the education of SLP and audiologists in South America. The suggested conclusion is that, despite the many differences, the South American SLP and audiologists' education would benefit from joint efforts and collaborative experiences.


Assuntos
Audiologia/educação , Comparação Transcultural , Patologia da Fala e Linguagem/educação , Brasil , Comportamento Cooperativo , Diversidade Cultural , Currículo/tendências , Educação Continuada/tendências , Educação de Pós-Graduação/tendências , Previsões , Política de Saúde/tendências , Necessidades e Demandas de Serviços de Saúde/tendências , Humanos , Prática Profissional/tendências , América do Sul , Recursos Humanos
11.
Clin Exp Pharmacol Physiol ; 35(8): 949-56, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18430058

RESUMO

(1) Increased plasma homocysteine content and increased blood pressure are independently associated with higher cardiovascular risks. The present study was designed to determine the effects of hyperhomocysteinaemia (HHcys) on the activity of the cardiovascular system in rats. (2) Using male Wistar rats, the effect of moderate HHcys, induced by treating rats with dl-homocysteine thiolactone (DL-HT; 1 g/kg per day) for 15 days, on arterial blood pressure, heart rate, baroreflex and vascular reactivity was determined. (3) Hyperhomocysteinaemia was observed after 15 days of treatment. Baseline arterial blood pressure and heart rate values of HHcys animals were significantly increased after 15 days of treatment. Plasma homocysteine and cardiovascular parameters returned to control values after termination of treatment. Baroreflex gain was significantly enhanced in HHcys rats. The pressor effect of an i.v. infusion of phenylephrine (50 mg/kg per mL) was decreased in HHcys rats and returned to control values after washout of DL-HT. Hypotensive responses to i.v. infusions of sodium nitroprusside (70 mg/kg per mL) or acetylcholine (10 mg/kg per mL) were increased in HHcys animals and returned to control values after washout of DL-HT. The increase in resting arterial blood pressure associated with the moderate HHcys was reversed by treatment with the b1-adrenoceptor antagonist atenolol, suggesting that HHcys-related hypertension is related to increase in cardiac sympathetic activity. (4) The present study showed significantly increased arterial blood pressure, heart rate and baroreflex activity in the early phase of moderate HHcys. In addition, HHcys was associated with alterations of vascular responsiveness to pressor and depressor agents, as well as increased cardiac sympathetic activity. The fact that cardiovascular changes observed in HHcys were reversed after DL-HT washout indicate that moderate HHcys evokes cardiovascular changes.


Assuntos
Sistema Cardiovascular/fisiopatologia , Modelos Animais de Doenças , Hiper-Homocisteinemia/fisiopatologia , Hipertensão/etiologia , Sistema Nervoso Simpático/fisiopatologia , Taquicardia/etiologia , Animais , Anti-Hipertensivos/uso terapêutico , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Cardiotônicos/uso terapêutico , Sistema Cardiovascular/efeitos dos fármacos , Sistema Cardiovascular/inervação , Frequência Cardíaca/efeitos dos fármacos , Homocisteína/sangue , Hiper-Homocisteinemia/sangue , Hiper-Homocisteinemia/induzido quimicamente , Hipertensão/tratamento farmacológico , Masculino , Nitroprussiato/uso terapêutico , Fenilefrina/uso terapêutico , Ratos Wistar , Sistema Nervoso Simpático/efeitos dos fármacos , Taquicardia/tratamento farmacológico , Resistência Vascular/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatadores/farmacologia
12.
Cranio ; 26(1): 50-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18290525

RESUMO

The mandibular movements used during speech modify space to allow different articulation postures proper for each sound. Temporomandibular disorders (TMD) may cause modifications in these movements due to joint and muscular conditions. The aim of this study was to verify the amplitude and the characterization of the mandibular movements during speech, using computerized electrognathography, in individuals with TMD and in asymptomatic individuals, analyzing possible interferences of these dysfunctions. One hundred thirty-five (135) adult subjects were divided into two groups: GI with 90 participants diagnosed with TMD and GIII with 45 asymptomatic participants. Their mandibular movements were observed during the sequential naming of pictures containing all of the word sounds, which occur in the Brazilian Portuguese language. The records were obtained with computerized electrognathography (BioEGN-BioPak system, BioResearch Associates, Inc., Milwaukee, WI). Mean values of the amplitude were described for the two groups. The analysis of such results showed statistically significant differences between the means of the values, obtained for the two groups in the opening and retrusion ranges. Statistically significant differences were not established for the presence and the range of the deviations in laterality, during speech. Prevalence of bilateral deviations was verified in GIII and unilateral deviations in GI. This study describes the 3-dimensional thresholds of mandibular movements in speech for Brazilian Portuguese, for the investigated individuals of both groups. The presence of TMD shows reduction in mandibular opening and retrusion ranges and prevalence of unilateral deviation movements during speech.


Assuntos
Mandíbula/fisiopatologia , Movimento/fisiologia , Fala/fisiologia , Transtornos da Articulação Temporomandibular/fisiopatologia , Adolescente , Adulto , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dimensão Vertical
13.
Ther Adv Cardiovasc Dis ; 2(3): 129-36, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19124416

RESUMO

INTRODUCTION: p27(Kip1) is a cyclin kinase inhibitor that induces cell cycle arrest. In this study, the efficacy of fusion protein TAT- p27(Kip1) to inhibit cell proliferation in rat perivascular injured carotid arteries was tested. METHODS: The cDNA of p27(Kip1) and GFP (green fluorescein protein) fused to the TAT epitope, which allows cell penetration, yielded TAT-p27 (Kip1) and TAT-GFP fusion proteins. In vitro biological activity on cell proliferation was evaluated by [(3)H] thymidine DNA incorporation in rabbit aortic endothelial cells (REC). An in vivo model used a silicone collar filled with saline positioned around the carotid vessel for 14 days to produce an increased adventitia cross-sectional area. RESULTS: TAT-p27(Kip1) inhibited REC proliferation in vitro using either 100, 200, and 500 nM compared to control (88.2 +/- 4.4, 81.3 +/- 7, 71.9 +/- 4.2 vs. 100 +/- 6.7%, N = 3, respectively, p < 0.05). This response was stable for purified proteins stored at -20*C for at least 23 days. In vivo , TAT-p27(Kip1) solution reduced adventitia cross-sectional area in a dose-dependent manner compared to TAT-GFP (area in mm(2) - TAT-p27(Kip1): 200 nM, 0.160 +/- 0.018; 500 nM, 0.050 +/- 0.005 vs. TAT-GFP: 500 nM, 0.595 +/- 0.066 vs. the contralateral: 0.047 +/- 0.005, N = 7, p < 0.01). CONCLUSION: Taken together, these results provide evidence that TAT-p27(Kip1) can inhibit vascular cells proliferation. It is the first successful demonstration that the cell permeable TAT-p27(Kip1) has potential as a vascular anti-proliferative agent.


Assuntos
Artérias Carótidas/citologia , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/fisiologia , Produtos do Gene tat , Animais , Aorta/citologia , Lesões das Artérias Carótidas/patologia , Células Cultivadas , Células Endoteliais/citologia , Endotélio Vascular/citologia , Epitopos , Masculino , Ratos , Ratos Wistar
14.
J Ethnopharmacol ; 110(1): 23-9, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17027208

RESUMO

The present work describes the mechanisms involved in the muscle relaxant effect of ethanol:water (40:60, 60:40 and 80:20) aerial parts extracts of Pimpinella anisum. Three hidroalcoholic extracts in which the proportion of ethanol was 40% (HA(40%)), 60% (HA(60%)) or 80% (HA(80%)) were tested for activity in the rat anococcygeus smooth muscle. The three extracts (50 microg/mL) inhibited acetylcholine-induced contraction. The extract HA(60%) (5-50 microg/mL) concentration dependently relaxed acetylcholine-pre-contracted tissues (31.55+/-3.56%). Conversely, HA(40%) and HA(80%) did not exert relaxant action. Pre-incubation of the preparations with N(G)-nitro-L-arginine methyl ester (L-NAME, 100 microM), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 3 microM) and oxyhemoglobin (10 microM) reduced the relaxation induced by HA(60%) (percentage of relaxation: 6.81+/-1.86%, 13.13+/-5.87% and 2.12+/-1.46%, respectively). Neither indomethacin (10 microM) nor tetraethylammonium (1 mM) affected the relaxation induced by HA(60%). Incubation of the tissues with L-NAME significantly enhanced the maximal contraction induced by acetylcholine, indicating an inhibitory role for NO in the modulation of the contractile response of anococcygeus smooth muscle to acetylcholine. However, simultaneous addition of L-NAME and HA(60%) resulted in an effect similar to that observed with L-NAME alone, further confirming the observation that Pimpinella anisum acts by realizing NO. Additionally, HA(60%) did not alter CaCl(2)-induced contraction. Collectively, our results provide functional evidence that the effects elicited by the hidroalcoholic extract of Pimpinella anisum involve the participation of NO and subsequent activation of the NO-cGMP pathway. The relaxant action displayed by Pimpinella anisum justifies its use in the folk medicine as an antispasmodic agent.


Assuntos
Músculo Liso/efeitos dos fármacos , Fármacos Neuromusculares/farmacologia , Parassimpatolíticos/farmacologia , Pimpinella/química , Extratos Vegetais/farmacologia , Animais , GMP Cíclico/metabolismo , Etanol , Masculino , Contração Muscular/efeitos dos fármacos , Óxido Nítrico/metabolismo , Ratos , Ratos Wistar
15.
Cranio ; 24(3): 197-206, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16933461

RESUMO

The precision of speech articulation is related to the possibility and freedom of the mandibular movements, modifying the spaces in order to allow the different articulatory positions of each sound. Electrognathography allows the objective delineation and registration of the mandibular movements, determining the level of opening, translations and velocity of these movements. Its use is a resource that can establish quantitative diagnostic parameters. The aim of this study was to verify the amplitude, velocity and characterization of the mandibular movements during speech using computerized electrognathography. Participants were 40 adults, male and female, with no temporomandibular disorders; with no missing teeth; with no dental occlusion alterations or dentofacial deformities; with no dental prostheses; and with no communication, neurological or cognitive deficits. The mandibular movements were observed during the sequential naming of pictures containing all the phonemes of the Brazilian Portuguese language. The registrations were obtained using electrognathography (BioENG-BioPak system), assessing the spatial position, course and velocity of the mandibular movements. The mean values of velocity were: 88.65 mm/sec during opening and 89.90mm/sec during closing. The mean values of amplitude were: sagittal opening: 12.77 mm, frontal opening: 11.21 mm, protrusion: 1.22 mm; retrusion 5.67 mm; translations to the right: 1.49 mm and to the left: 1.59 mm. The velocity of opening is directly related to that of closing. The amplitude of opening demonstrates a direct correlation with the velocity of opening and closing. All participants presented lateral translations during the course of the jaw. The assessment of speech in normal individuals is characterized by: discreet mandibular movements with an anteroposterior component and lateral translations. This study allowed for the delineation of a profile of the mandibular movements during speech in asymptomatic individuals.


Assuntos
Mandíbula/fisiologia , Testes de Articulação da Fala , Fala/fisiologia , Adolescente , Adulto , Brasil , Feminino , Humanos , Registro da Relação Maxilomandibular , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Movimento , Projetos Piloto , Amplitude de Movimento Articular , Patologia da Fala e Linguagem/métodos , Estatísticas não Paramétricas , Articulação Temporomandibular/fisiologia
16.
Toxicol Appl Pharmacol ; 213(1): 10-7, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16256160

RESUMO

We aimed to investigate the mechanisms underlying the vascular effects induced by phylloquinone (Vitamin K1; VK1). Vascular reactivity experiments, using standard muscle bath procedures, showed that VK1 (5 and 50 microM) enhances the contractile response of endothelium-intact, but not denuded, rat carotid rings to phenylephrine. Similarly, maximal contraction induced by phenylephrine was enhanced in the presence of the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME). The combination of L-NAME and VK1 did not produce any further additional effect. Pre-incubation of intact-rings with VK1 reduced both acetylcholine- and bradykinin-induced relaxation. VK1 induced an increment in tension on carotid rings submaximally pre-contracted with phenylephrine. VK1-induced increment in tension was completely abolished by endothelial removal or incubation of intact rings with L-NAME and L-NNA. Conversely, 7-nitroindazole, 1400 W, or indomethacin did not affect VK1-induced contraction. Moreover, VK1 reduced L-arginine-induced relaxation in endothelium-intact rings. Lucigenin-amplified chemiluminescence assays showed that VK1 induced an increase in the level of superoxide anions in endothelium-intact but not denuded rings. Measurement of nitrite and nitrate generation showed that VK1 did not alter nitrate formation but strongly inhibited the generation of nitrite. Finally, the superoxide anions scavenger tiron prevented the endothelial vasomotor dysfunction caused by VK1 on phenyleprine-induced contraction and acetylcholine or bradykinin-induced relaxation. In conclusion, our data show that VK1 disrupts the vasomotor function of rat carotid. Our results suggest that VK1-induced oxidative stress through production of superoxide anion is interfering with the NO pathway, which in turn is responsible for the altered vascular reactivity induced by VK1.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Estresse Oxidativo , Vitamina K 1/farmacologia , Vitaminas/farmacologia , Animais , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/fisiopatologia , Endotélio Vascular/fisiopatologia , Masculino , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Ratos , Ratos Wistar
17.
J Smooth Muscle Res ; 40(6): 249-58, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15725707

RESUMO

This study was performed to determine the effect of forced swimming on the vascular responsiveness of the rat superior mesenteric artery to phenylephrine, focusing on the involvement of locally produced substances. Repeated but not single sessions of forced swimming exercise reduced the vasoconstrictor potency of phenylephrine in the studied arteries, regardless of the presence of intact endothelium. No significant changes were observed in the maximal response to phenylephrine. Treatment with indomethacin (1 microM) did not affect the exercise-induced reduction in vascular responsiveness to phenylephrine. However, the reduction of vascular reactivity to phenylephrine due to repeated exercise was no longer observed after treatment with N(G)-monomethyl-L-arginine (L-NMMA, 100 microM). The results suggest that repeated exercise reduces vasomotor responses to phenylephrine in rat superior mesenteric arteries through a non-endothelial nitric oxide (NO)-related mechanism.


Assuntos
Artérias Mesentéricas/fisiologia , Músculo Liso Vascular/efeitos dos fármacos , Fenilefrina/farmacologia , Natação/fisiologia , Vasoconstritores/farmacologia , Animais , Relação Dose-Resposta a Droga , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Esforço Físico/fisiologia , Ratos , Ratos Wistar , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologia
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