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Research Interests: Biology and Wild Plants
Apesar de não ser desejável, os produtos cosméticos podem ocasionar alguns efeitos adversos ao usuário. Tais efeitos podem ser decorrentes de fatores individuais como também pelo uso inadequado. Logo, a avaliação de segurança deve... more
Apesar de não ser desejável, os produtos cosméticos podem ocasionar alguns efeitos adversos ao usuário. Tais efeitos podem ser decorrentes de fatores individuais como também pelo uso inadequado. Logo, a avaliação de segurança deve preceder a colocação do produto cosmético no mercado. Uma vez que o produto cosmético é de livre acesso ao consumidor, o mesmo deve ser seguro nas condições normais ou razoavelmente previsíveis de uso. Historicamente, os testes de avaliação de segurança eram realizados com animais (in vivo); porém, atualmente, alguns centros de pesquisa estão adotando novas alternativas (in vitro) que visam a substituição dos testes com animais. Este artigo enfatiza a necessidade de realização de ensaios de toxicidade para produtos de higiene pessoal, cosméticos e perfumes, bem como apresenta os testes in vivo e in vitro utilizados abordando a necessidade de se aplicar métodos alternativos aos ensaios in vitro na avaliação de segurança dos mesmos.Although not desirable, co...
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Nanoparticulas de prata (AgNPs) apresentam caracteristicas antibacteriana, antifungica e antiviral com inumeras aplicacoes na medicina, dentre as quais, nos tratamentos das lesoes teciduais para que nao resulte em necrose tecidual... more
Nanoparticulas de prata (AgNPs) apresentam caracteristicas antibacteriana, antifungica e antiviral com inumeras aplicacoes na medicina, dentre as quais, nos tratamentos das lesoes teciduais para que nao resulte em necrose tecidual (irreversivel) levando a amputacao ou ate mesmo em morte. Venenos botropicos sao ricos exemplos de agentes causadores de lesao local, que pode resultar em extensiva necrose tecidual. OBJETIVOS : Realizar testes de mutagenicidade atraves do teste de Ames do veneno de Bothrops jararacussu (Bjssu), das AgNPs 50 nm e da mistura AgNPs + Bjssu. METODO : A partir da realizacao do teste de toxicidade pelo teste de Ames para o veneno Bjssu, AgNPs (50 nm) e da mistura veneno- AgNPs dissolvidos em DMSO e ensaiadas com as linhagens de Salmonella typhimurium TA98 e TA100, sem ativacao metabolica (Projeto IC Edital 2016-2017), pode-se conduzir o teste de mutagenicidade atraves do teste de Ames, com as linhagens de S. typhimurium TA97a, TA 98, TA 100 e TA 102, com e sem ativacao metabolica para os mesmos compostos acima. RESULTADOS ESPERADOS : A partir dos resultados do teste de mutagenicidade conhecer-se-a o potencial mutagenico (ou antimutagenico) do veneno de Bjssu, das AgNPs 50 nm e da mistura Bjssu + AgNPs 50 nm.
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Research Interests: Pharmacology, Zoology, Chemistry, Heparin, Venom, and 4 moreAntivenom, Snake Venom, Venomous snakes, and Bothrops
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Research Interests: Pharmacology, Medicine, Fibers, Farmacia, Skeletal Muscle, and 12 moreNitric Oxide Synthase, Carbamazepine, Receptors, Antiepileptic drugs, Neuromuscular Junction, Medicamento, Phenobarbital, Blockade, Depolarization, Sistema Nervioso Central, Pharmacologic actions, and Pharmacology and pharmaceutical sciences
Glyphosate is an organophosphate herbicide widely used in agriculture and has been classified as a probable carcinogen by the International Agency for Research on Cancer (IARC). Roundup Original Mais (ROM) is a glyphosate-based herbicide... more
Glyphosate is an organophosphate herbicide widely used in agriculture and has been classified as a probable carcinogen by the International Agency for Research on Cancer (IARC). Roundup Original Mais (ROM) is a glyphosate-based herbicide that contains glyphosate along with other ingredients, and its effects on human health are still a matter of controversy. This study aimed to compare the toxicity of ROM, gradual purified organic extract until pure glyphosate, on serum cholinesterase. Petroleum ether organic extracts of ROM were obtained through procedure A, in which ROM was solubilized in water followed by acetone purification, and procedure B, in which procedure A was submitted to alkalization with 1 M NaOH at pH=11 aiming for purification. Enzymatic activities of ROM, organic extracts obtained from procedures A and B, pure glyphosate, neostigmine (an anticholinesterase agent as positive control), and serum alone (negative control) were detected using a commercial kit for cholines...
Introduction Mikania laevigata Schultz Bip. Ex Baker, popularly known as guaco, had its use approved as a phytomedicine bronchodilator by Brazilian regulatory agency, since exerts a trachea relaxation which is attributed to coumarin, the... more
Introduction Mikania laevigata Schultz Bip. Ex Baker, popularly known as guaco, had its use approved as a phytomedicine bronchodilator by Brazilian regulatory agency, since exerts a trachea relaxation which is attributed to coumarin, the main biomarker of guaco. The role of diaphragm muscle in the respiration face to guaco extract was investigated comparatively to salbutamol and coumarin, aiming to verify the better extract from nonpolar to polar extracts of M. laevigata. Methods A validated experimental model of mouse phrenic nervediaphragm (PND) preparation was used. The diaphragm aids in breathing contracting muscle fibers, so we sought a facilitatory effect on these different extracts based on their polarity. An inconvenience for studying substances of different polarities is become them soluble in water, since the biological preparation is maintained in a nutritive solution. We selected polyethylene glycol 400 (PEG400) and dimethyl sulfoxide (DMSO) as solubilizers, while coumar...
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Programa de Pos-Graduacao em Ciencias Farmaceuticas Faculdade de Ciencias Farmaceuticas de Araraquara Universidade Estadual Paulista Julio de Mesquita Filho, Rodovia Araraquara-Jau, Km 1, 14801-902, Araraquara - SP
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O objetivo deste estudo foi avaliar as atividades neurotoxica e miotoxica das peconhas de Crotalus duhssus tenificus (Cdt,10 ng/ml), Bothrops jararacussu (Bjssu, 50 ng/ml) e de suas principais toxinas, crotoxina (CrTX, 10 ng/ml) e... more
O objetivo deste estudo foi avaliar as atividades neurotoxica e miotoxica das peconhas de Crotalus duhssus tenificus (Cdt,10 ng/ml), Bothrops jararacussu (Bjssu, 50 ng/ml) e de suas principais toxinas, crotoxina (CrTX, 10 ng/ml) e bothropstoxina (BthTX, 20 ng/mi), respectivamente. Utilizamos antivenenos (AV) comerciais e especificos para avaliar a capacidade de neutralizacao dessas atividades, em preparacoes biologicas (camundongo), nervo frenico-diafragma (NFD) e extensor digitorum longus (EDL). O AV equino comercial empregado foi produzido pelo Instituto Vital Brazii. O AV especifico foi produzido por inoculacao sucessiva, em coelhos, com veneno totat de Cdt, Bjssu e da toxina CrTX. O acompanhamento da producao de anticorpos foi realizado por imunodifusao e, posteriormente, confirmado pela tecnica de ELISA. A atividade neurotoxica foi avaliada por intermedio de tecnica miografica e a miotoxica, atraves de determinacao de creatinoquinase (CK), in vitro, e de analise histologica. Os dois venenos e suas respectivas toxinas produziram bloqueio neuromuscular dose-dependente e mionecrose, em diferentes graus. O estudo do bloqueio neuromuscular evidenciou diferencas entre as preparacoes utilizadas (NFD e EDL), quanto a sensibilidade aos venenos e toxinas, provavelmente pela constituicao predominante de fibras de contracao rapida (EDL) e lenta (NFD). A neutralizacao do bloqueio neuromuscular mostrou ser dose-dependente na preparacao NFD e, a partir de determinada dose de AV, foi registrada uma facilitacao importante para os AV comerciais. A neutralizacao cruzada tambem foi investigada para Bjssu e BthTX, em ambas as preparacoes, e novamente a resposta foi diferente entre elas. Os elevados niveis obtidos da enzima CK, liberada apos 120 minutos de exposicao aos AV, sozinhos, o que pretendia ser um simples controle, revefou que, possivelmente a quantidade de proteinas interfira no mecanismo liberador de CK Isto sugere que a determinacao enzimatica, em associacao a analise histologica, pode constituir um parâmetro quantitativo de mionecrose, mas deve ser interpretada com cuidado na avaliacao de lesao celular se estudada individualmente. A analise histologica revelou que a capacidade do veneno botropico de destruir a musculatura esqueletica e maior do que a do crotalico, nas condicoes experimentais empregadas. Os AV especificos foram eficientes na neutralizacao da miotoxicidade. Pode-se concluir que, o estudo da neutralizacao com AV produzido de fracoes purificadas, associada aos parâmetros miograficos e miotoxicos, pode constituir um modelo util na dissociacao entre as atividades neurotoxica e miotoxica das toxinas Abstract
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Copyright © 2013 Lia de Barros Leite Albuquerque et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the... more
Copyright © 2013 Lia de Barros Leite Albuquerque et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Scientific assessment of harmful interactions of chemicals over the entire reproductive cycle are divided into three segments based on the period: from premating and mating to implantation (I), from implantation to major organogenesis (II), and late pregnancy and postnatal development (III). We combined the segments I and II to assess Plathymenia reticulata aqueous extract safety. In order to investigate reproductive toxicity (segment I), pregnant rats received orally 0.5 or 1.0 g/kg of extract, daily, during 18 days. These concentrations were determined by a preliminary in vitro LD50 test in CHO-k1 cells. A control group received deionized water. The offspring was removed at the 19th day, by caesarean, and a teratol...
INTRODUCAO:INTRODUCAO: A doxiciclina e um bacteriostatico pertencente ao grupo das tetraciclinas, com espectro de acao sobre bacterias gram-positivas e gram-negativas. E utilizada no tratamento de infeccoes, inclusive do sistema nervoso... more
INTRODUCAO:INTRODUCAO: A doxiciclina e um bacteriostatico pertencente ao grupo das tetraciclinas, com espectro de acao sobre bacterias gram-positivas e gram-negativas. E utilizada no tratamento de infeccoes, inclusive do sistema nervoso central, por conta de sua elevada lipossolubilidade. Atraves de modelos experimentais de doencas neurodegenerativas tanto in vivo como in vitro, incluindo a Doenca de Parkinson (DP), demonstrou-se que a doxiciclina tem efeito neuroprotetor tornando-se uma promessa ao tratamento da DP.O efeito protetor de tetraciclinas (incluindo a doxiciclina) e estendido em desordens neuromusculares (uma disfuncao de neuronios motores, nervos perifericos, juncao neuromuscular, ou do proprio musculo). Por outro lado, antibioticos incluindo tetraciclinas, sulfonamidas, penicilinas, aminoacidos antibioticos tem sido associados com relatos de aumento da fraqueza miastenica. OBJETIVO: O objetivo deste estudo e avaliar a influencia da administracao oral e cronica da doxic...
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The ability of <i>Terminalia fagifolia</i> hydroalcoholic extract (<i>Tf</i>-HE) to neutralise the paralysis and myotoxicity induced by <i>Bothrops jararacussu</i> venom was assayed using mouse phrenic... more
The ability of <i>Terminalia fagifolia</i> hydroalcoholic extract (<i>Tf</i>-HE) to neutralise the paralysis and myotoxicity induced by <i>Bothrops jararacussu</i> venom was assayed using mouse phrenic nerve-diaphragm (PND) preparation and two varieties of chick biventer cervicis (BC) preparations. <i>Tf</i>-HE 100 μg/mL and 500 μg/mL were tested against 40 and 200 μg of venom/mL in PND and BC preparations, respectively, using pre- and post-venom incubation treatments. The effects of <i>Tf</i>-HE against the myotoxicity caused by venom were evaluated via histological analysis (PND) and creatine kinase (CK) release (BC). <i>Tf</i>-HE was able to reverse the venom paralysis in both preparation types. The contractures to exogenous ACh in BC preparations showed that <i>Tf</i>-HE may act on extrinsic, preserving those intrinsic postsynaptic receptors. There was a positive correlation between CK and morpho...
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Introduction: Rhinella schneideri is a toad widely distributed in South America and its poison is characterized by inducing cardiotoxicity and neurotoxicity. Objective: In this work, we investigated pharmacological strategies to attenuate... more
Introduction: Rhinella schneideri is a toad widely distributed in South America and its poison is characterized by inducing cardiotoxicity and neurotoxicity. Objective: In this work, we investigated pharmacological strategies to attenuate the peripheral neurotoxicity induced by R. schneideri poison in avian neuromuscular preparation. Methods: The experiments were carried out using isolated chick biventer cervicis preparation subjected to field stimulation for muscle twitches recordings or exposed to acetylcholine and potassium chloride for contracture responses. Results: Poison (10 μg/ml) produced complete neuromuscular blockade in chick biventer cervicis preparation within approximately 70 min incubation (times for 50 and 90 % blockade: 15 ± 3 min and 40 ± 2 min, respectively; P < 0.05, N= 5); contracture responses to exogenous acetylcholine and KCl were unaffected by poison indicating no specificity with postsynaptic receptors or myotoxicity, respectively. Poison (10 μg/ml)-ind...
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O objetivo deste trabalho e divulgar os resultados de pesquisa sobre os neurotransmissores envolvidos com os efeitos do alcool no sistema nervoso central. Realizou-se um levantamento bibliografico em livros didaticos, em base de dados... more
O objetivo deste trabalho e divulgar os resultados de pesquisa sobre os neurotransmissores envolvidos com os efeitos do alcool no sistema nervoso central. Realizou-se um levantamento bibliografico em livros didaticos, em base de dados Medline e Scielo, enfatizando-se publicacoes a partir da decada de 90. Os descritores foram dependencia quimica, neurotransmissores, tolerância a drogas e sindrome de abstinencia, cruzados aleatoriamente com a palavra alcool. Foram selecionados doze artigos cientificos que atenderam ao objetivo proposto. Os principais neurotransmissores relacionados com a psicofarmacologia do alcool encontrados foram o GABA, dopamina, glutamato e opioides.
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Nanoparticulas de prata (AgNPs) apresentam caracteristicas antibacteriana, antifungica e antiviral com inumeras aplicacoes na medicina, dentre as quais, nos tratamentos das lesoes teciduais para que nao resulte em necrose tecidual... more
Nanoparticulas de prata (AgNPs) apresentam caracteristicas antibacteriana, antifungica e antiviral com inumeras aplicacoes na medicina, dentre as quais, nos tratamentos das lesoes teciduais para que nao resulte em necrose tecidual (irreversivel) levando a amputacao ou ate mesmo em morte. Venenos botropicos sao ricos exemplos de agentes causadores de lesao local, que pode resultar em extensiva necrose tecidual. OBJETIVOS : Realizar testes de mutagenicidade atraves do teste de Ames do veneno de Bothrops jararacussu (Bjssu), das AgNPs 50 nm e da mistura AgNPs + Bjssu. METODO : A partir da realizacao do teste de toxicidade pelo teste de Ames para o veneno Bjssu, AgNPs (50 nm) e da mistura veneno- AgNPs dissolvidos em DMSO e ensaiadas com as linhagens de Salmonella typhimurium TA98 e TA100, sem ativacao metabolica (Projeto IC Edital 2016-2017), pode-se conduzir o teste de mutagenicidade atraves do teste de Ames, com as linhagens de S. typhimurium TA97a, TA 98, TA 100 e TA 102, com e sem ...
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Introduction Silver nanoparticles (AgNPs) are of particular interest for their antibacterial properties and are produced by the action of reducing agents on silver ions. Curcumin from Curcuma longa (Zingiberaceae) has been used as a... more
Introduction Silver nanoparticles (AgNPs) are of particular interest for their antibacterial properties and are produced by the action of reducing agents on silver ions. Curcumin from Curcuma longa (Zingiberaceae) has been used as a precursor for obtaining biogenic AgNPs, to act as a potential drug. Objectives This study aimed to evaluate the toxicity of AgNPs synthesized with curcumin (Cur-AgNPs 0.081 mg/mL, ~130 nm) through the Salmonella/microsome (Ames test), one of the first required assays for evaluating toxicity. Methods The study design was experimental and in vitro. After defining the preliminary toxicity, the mutagenicity was assessed in a concentration range of 0.0010–0.0081 mg/plate Cur-AgNPs using histidine negative (His−) Salmonella Typhimurium strains TA97a, TA98, TA100, and TA102, with (+S9) and without metabolic activation (−S9), in triplicate. Assays were monitored by positive and negative controls. The results were statistically analyzed by Salanal software with p...
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INTRODUCAO : Acidentes ofidicos possuem grande casuistica em todo o territorio brasileiro. Dentre os casos, mais de 80% foram provocados por serpentes do genero Bothrops no ano de 2015, sendo que a especie Bothrops jararacussu e uma das... more
INTRODUCAO : Acidentes ofidicos possuem grande casuistica em todo o territorio brasileiro. Dentre os casos, mais de 80% foram provocados por serpentes do genero Bothrops no ano de 2015, sendo que a especie Bothrops jararacussu e uma das de maior relevância. Eriope blanchetii e uma planta brasileira endemica que produz quantidades consideraveis de acido betulinico e tambem os acidos oleanolico e ursolico, compostos que possuem propriedades anti-inflamatorias, antitumorais, antimicrobiana, antioxidante e antinociceptiva. OBJETIVO : O objetivo deste projeto e verificar atraves de microscopia de luz o grau de protecao do acido ursolico contra a miotoxicidade induzida pelo veneno de Bothrops jararacussu , de musculos diafragmas recebidos por doacao. METODO : Os musculos lesionados por veneno ofidico e tratados com acido ursolico (resultantes de modelos farmacologicos de pre incubacao e pos veneno) serao processados de acordo com metodos de rotina em parafina, seccionados atraves de micro...
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INTRODUCAO: O tema desta pesquisa e enderecado ao aspecto da seguranca quanto ao tratamento da alopecia, doenca que provoca a queda de cabelos. De uso recente, os indutores de crescimento foram incluidos entre os medicamentos utilizados... more
INTRODUCAO: O tema desta pesquisa e enderecado ao aspecto da seguranca quanto ao tratamento da alopecia, doenca que provoca a queda de cabelos. De uso recente, os indutores de crescimento foram incluidos entre os medicamentos utilizados no tratamento da alopecia, em conjunto a outros farmacos, para auxiliar no aumento da densidade e da microcirculacao e favorecer a diferenciacao folicular e a renovacao dos fios de cabelos perdidos. Nao se tem informacao do impacto da associacao do Blend de fatores de crescimento capilar (IGF, bFGF, VEGF, e peptideos de cobre) a um farmaco classico, como a finasterida, pelo parâmetro da mutagenicidade, garantindo ineditismo a este estudo. OBJETIVO: Avaliar a toxicidade preliminar da finasterida, do Blend de fator de crescimento capilar e da mistura ( Blend + finasterida), pelo parâmetro da mutagenicidade ( Salmonella /microssoma). DELINEAMENTO DO ESTUDO: Estudo experimental in vitro METODOS: O metodo utilizado foi o teste de Toxicidade Prelimina...
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Many natural products influence neurotransmission and are used clinically. In particular, facilitatory agents can enhance neurotransmission and are potentially useful for treating neuromuscular diseases in which muscular weakness is the... more
Many natural products influence neurotransmission and are used clinically. In particular, facilitatory agents can enhance neurotransmission and are potentially useful for treating neuromuscular diseases in which muscular weakness is the major symptom. In this work, we investigated the facilitatory effect of apolar to polar fractions of Casearia sylvestris Sw. (guaçatonga) on contractility in mouse phrenic nerve-diaphragm (PND) and chick biventer cervicis (BC) neuromuscular preparations exposed to indirect (via the nerve; 3 V stimuli) and direct (30 V stimuli) muscle stimulation in the absence and presence of pharmacological antagonists. Methanolic and ethyl acetate fractions, but not hexane or dichloromethane fractions, exerted a facilitatory effect on PND (indirect stimulation). The methanolic fraction was chosen for further assays to assess the involvement of: 1) presynaptic sites (axons or nerve terminals), 2) postsynaptic sites (cholinergic receptors, sarcolemma or T-tubules), and 3) the synaptic cleft (acetylcholinesterase enzyme). In preparations treated with d-tubocurarine, the methanolic fraction did not cause facilitation in response to direct stimuli; this fraction was also unable to reverse dantrolene-induced blockade (indirect stimulation). In curarized preparations, the methanolic fraction either restored neuromuscular transmission (mimicking the effect of neostigmine) or failed to cause any recovery of neurotransmission. In the presence of 3,4-diaminopyridine (3,4-DAP), the methanolic fraction decreased twitch amplitude, whereas at a high frequency of stimulation (40 Hz) there was an increase in tetanic tension. In BC preparations, the methanolic fraction did not affect contractures to exogenous acetylcholine or potassium chloride. Incubation with atropine showed there was certain modulation by prejunctional nicotinic receptors, whereas treatment with nifedipine showed that the neurofacilitation required the entry of extracellular calcium. Tetrodotoxin did not prevent the facilitatory effect of 3,4-DAP or neostigmine, but antagonized the response to the methanolic fraction. These findings indicate that neuronal sodium channels have an important role in the facilitatory response to the methanolic fraction, with extracellular calcium entry via calcium channels modulating this neurofacilitation. Possible modulation of prejunctional cholinoceptors was not excluded, particularly in view of certain antagonism by the methanolic fraction at muscarinic receptors. Since facilitation by the methanolic fraction involved enhanced acetylcholine release, use of this fraction could be potentially beneficial in neuromuscular diseases and in the reversal of residual paralysis in the post-operative period or after local anaesthesia.
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Charcoal hemoperfusion (CHP) is one of the extracorporeal removal techniques that are used to remove toxins from the body. CHP generally is considered the preferred method for extracorporeal extraction of several toxins—toxins that are... more
Charcoal hemoperfusion (CHP) is one of the extracorporeal removal techniques that are used to remove toxins from the body. CHP generally is considered the preferred method for extracorporeal extraction of several toxins—toxins that are adsorbed by activated charcoal. Assessments of the tannic acid’s protective effects on ophidian poisoning are associated with the toxic proteins’ precipitation by tannic acid. The challenge in treating a snakebite lies in removing the injected poison with minimal damage to blood constituent proteins. An alternative is CHP, and this investigation proposed to develop a column for hemoperfuser cartridge, combining charcoal granules trapped between layers of polymeric material conjugated to tannic acid, using an in vitro model scaled to the Wistar rat, which can be tested in an animal model. The cartridge was evaluated using the 22 full factorial design, in duplicate, as a method to study the effects of granulated-charcoal size and tannic acid concentrati...
A juncao neuromuscular (JNM) e formada por sinapses entre um nervo motor e um musculo esqueletico. Ensaios farmacologicos realizados na JNM sao de extrema importância, pois permitem testar, validar e estudar a farmacodinâmica de diversas... more
A juncao neuromuscular (JNM) e formada por sinapses entre um nervo motor e um musculo esqueletico. Ensaios farmacologicos realizados na JNM sao de extrema importância, pois permitem testar, validar e estudar a farmacodinâmica de diversas substâncias. Uma preparacao neuromuscular muito utilizada para este proposito e a preparacao ex vivo Nervo Frenico-Diafragma (NFD). O objetivo deste trabalho foi pesquisar sobre o uso da preparacao NFD de camundongos/ratos atraves de tecnica miografica. A metodologia empregada na pesquisa foi realizada utilizando-se “rats or mouse phrenic nerve-diaphragm preparation” como descritores, nas bases de dados PubMed, Google Academico, SciElo e Periodicos CAPES. Os criterios de inclusao foram artigos que utilizaram ambos, preparacao NFD e tecnica miografica, no periodo de 1946 a 2019. A JNM representa anatomicamente a sinapse nervo-musculo, simples de ser isolada e facil de ser estudada. Ha diversos protocolos farmacologicos (pre-, pos- e na fenda sinaptic...
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Bothropstoxin-I (BthTX-I) from Bothrops jararacussu snake venom has a predominantly postsynaptic action that is responsible for this toxins myotoxicity. However, BthTX-I also has a presynaptic action that is counteracted by Mn 2+ , a... more
Bothropstoxin-I (BthTX-I) from Bothrops jararacussu snake venom has a predominantly postsynaptic action that is responsible for this toxins myotoxicity. However, BthTX-I also has a presynaptic action that is counteracted by Mn 2+ , a reversible neuromuscular blocker that acts predominantly presynaptically. In this work, we used two nerve-muscle preparations (mouse phrenic nerve-diaphragm - PND and extensor digitorum longus - EDL) to investigate the ability of Mn 2+ to protect against the myotoxicity of BthTX-I. The preparations were incubated with Tyrode solution (control), BthTX-I, or Mn 2+ alone. BthTX-I (1.4 μM) produced irreversible blockade in both preparations, whereas the blockade by Mn 2+ (0.9 mM) was total and reversible in PND but just partially reversible in EDL. Pretreating the preparations with Mn 2+ resulted in 100% and 80% protection against BthTX-I-induced blockade, respectively. However, when Mn 2+ (0.9 or 1.8 mM) and BthTX-I (1.4 μM) were co-incubated for 30 min be...
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Hexane (HEX), dichloromethane (DM), ethyl acetate (EA) and methanol (M) extracts (0.1, 0.2 and 0.4mg/ml) were obtained via Soxhlet from Plathymenia reticulata barks (Pr). These extracts were evaluated against the myotoxicity (58%) and the... more
Hexane (HEX), dichloromethane (DM), ethyl acetate (EA) and methanol (M) extracts (0.1, 0.2 and 0.4mg/ml) were obtained via Soxhlet from Plathymenia reticulata barks (Pr). These extracts were evaluated against the myotoxicity (58%) and the irreversible in vitro neuromuscular blockade of Bothrops jararacussu (Bjssu) venom (40μg/ml) in a mouse phrenic-nerve diaphragm preparation, by using light-microscopy and conventional myographic techniques. Thin layer chromatography (TLC) was used to access the basic composition of extracts. The efficacy of the extracts was analyzed by Student's t-test or repeated measures ANOVA. The significance level was set at 5%. The Pr extracts showed a higher polyphenols content (3.75%), from which tannins take part, around 20 times more than flavonoids content (0.16%). Qualitatively, via TLC, DM and EA extracts showed higher tannins concentration than the HEX and M extracts. Pharmacologically, at 0.4mg/ml, DM was more effective (92 ± 6.2%) than EA (81.3 ...
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The neurotoxic effects of manganese occured mainly from its inhalation are well described in the literature. In this study we have been demonstrated the potent and reversible effect of manganese ions (Mn²+) on neuromuscular transmission... more
The neurotoxic effects of manganese occured mainly from its inhalation are well described in the literature. In this study we have been demonstrated the potent and reversible effect of manganese ions (Mn²+) on neuromuscular transmission using conventional myographic. The Mn²+ mechanism wich causes reversible blockade at neuromuscular junction was investigated in isolated mouse phrenic nerve-diaphragm (PND) preparations. As much Mn²+ 0.9 mM as Mn²+ 1.8 mM produced rapid neuromuscular blockade (50% in
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This research evaluated the effect of Bothrops moojeni venom on neuromuscular activity and verified the antiophidian potential of the J. elliptica starch (JeP) in this model. The venom was obtained from snakes collected in the state of... more
This research evaluated the effect of Bothrops moojeni venom on neuromuscular activity and verified the antiophidian potential of the J. elliptica starch (JeP) in this model. The venom was obtained from snakes collected in the state of Tocantins, the protein profile evaluated in electrophoresis (SDS-PAGE), and the activity on the phrenic-diaphragm nerve of mice determined in 50 μg/mL of venom. The JeP, obtained by hand, was sieved in a sieve for granulometric analysis, and concentrations of 100 and 1000 μg/mL were tested to verify its antiophidian potential on the action of the poison. The following models were used: pre-venom addition of venom and after 15 min addition of JeP; post-poison addition of JeP and after 15 min the addition of poison; and pre-incubation for 30 min, of poison with JeP or commercial antivenom. The poison had proteins from 10 to 60 kDa, which induced 50% of neuromuscular activity block in 71.5 ± 8.9 min (T50). The pre-venom and post-venom models with JeP 100...
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A bothropstoxina-I (BthTX-I), principal miotoxina do veneno de Bothrops jararacussu, tem atividades neurotoxica e miotoxica. Investigou-se a habilidade do antiveneno crotoxinico e da heparina em prevenir as atividades neurotoxica e... more
A bothropstoxina-I (BthTX-I), principal miotoxina do veneno de Bothrops jararacussu, tem atividades neurotoxica e miotoxica. Investigou-se a habilidade do antiveneno crotoxinico e da heparina em prevenir as atividades neurotoxica e miotoxica da BthTX-I. Preparacoes nervo ftenico-diaftagma (NFD) de camundongos estimuladas indiretamente (0.2 ms, O.I Hz) foram incubadas com BthTX-I (20 flglmI) ou com BthTX-I pre-incubada com antiveneno ou heparina, por 30 min a 37°C. BthTX-I (20 flg/ml) produziu 50% de bloqueio neuromuscular em preparacoes NFD em 31 :t 4 min, com completo bloqueio ocorrendo aos 120 mino...Observacao: O resumo, na integra, podera ser visualizado no texto completo da tese digital Abstract
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INTRODUCAO : Nanoparticulas de prata (AgNPs) apresentam caracteristicas antibacteriana, antifungica e antiviral com inumeras aplicacoes na medicina. Venenos botropicos sao ricos exemplos de agentes causadores de lesao local, que pode... more
INTRODUCAO : Nanoparticulas de prata (AgNPs) apresentam caracteristicas antibacteriana, antifungica e antiviral com inumeras aplicacoes na medicina. Venenos botropicos sao ricos exemplos de agentes causadores de lesao local, que pode resultar em extensiva necrose tecidual. A avaliacao de toxicidade em testes in vitro como citotoxicidade, apoptose celular e genotoxicidade tem foco principalmente no câncer, identificando potenciais carcinogenos ou antimutagenicos. OBJETIVOS : Avaliar a toxicidade, pelo teste de Ames, do veneno de Bothrops jararacussu (Bjssu), das AgNPs 50 nm e da mistura AgNPs + Bjssu. METODOS : Testaram-se concentracoes iniciais do veneno Bjssu (40 µg/mL, 200 µg/mL, 1 mg/mL e 5 mg/mL), AgNPs 50 nm (0,081 mg/mL) e mistura Bjssu (5 mg/mL) + AgNPs (0,0405 mg/mL), ensaiados com as linhagens de Salmonella typhimurium TA98 e TA100, sem ativacao metabolica. RESULTADOS : Foram observadas as toxicidades das substâncias nas concentracoes finais 11,57 µg/mL de AgNPs, de Bjssu 7...
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Many diseases are related to the use of tobacco, but the moment when the harmful effects overcome the mechanisms of defense of the organism is not known. The aim of this study was find out whether biochemical, hematological and... more
Many diseases are related to the use of tobacco, but the moment when the harmful effects overcome the mechanisms of defense of the organism is not known. The aim of this study was find out whether biochemical, hematological and immunological changes occur in young adult smokers, compared to young adult nonsmokers. Twenty-four non-smokers and 14 smokers (smoking an average of 10±4.9 cigarettes a day for 8±1 years), all students of health science courses (Pharmacy, Nutrition and Occupational therapy at Uniso), whose average age was 23±3.6 years, participated in the study. Samples of blood were collected by appropriate techniques for the following analyses: total cholesterol, HDL-cholesterol, LDL and VLDL-cholesterol, triglycerides, glucose, urea, uric acid and serum creatinine. Both groups were found to be normolipidemic, euglycemic, with serum values of urea, creatinine, uric acid, C-reactive protein (CRP), immunoglobulin G (IgG) and M (IgM), complement C3 and complete blood count (w...
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In geographically isolated populations where intensive medical care or serum therapy is not easily accessible snake envenomation is a major cause for concern. The aim of the present study was to test Camellia sinensis extracts, theaflavin... more
In geographically isolated populations where intensive medical care or serum therapy is not easily accessible snake envenomation is a major cause for concern. The aim of the present study was to test Camellia sinensis extracts, theaflavin and epigallocatechin (two of the main C. sinensis components) against the irreversible neuromuscular blockade induced by Crotalus durissus terrificus venom in mouse phrenic-nerve diaphragm preparations. A quantitative histological study was also performed. The venom (20µg/ml) completely decreased twitch tension after 70min and 5µg/ml venom abolished 50% of twitch amplitude after 60min. C. sinensis extract induced intense facilitatory effect in the preparation activity at 0.2mg/ml and slightly facilitatory effect at 0.05mg/ml. Both 0.05mg/ml C. sinensis extract and 0.05mg/ml commercial theaflavin maintained partial muscular activity in presence of 5µg/ml venom. The histological data confirms that Cs is able to protect the muscle from the myotoxic ac...