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Id: biblio-1287090
Autor: Ahmed, Mushtaq; Khan, Shahan Zeb; Sher, Naila; Rehman, Zia Ur; Mushtaq, Nadia; Khan, Rahmat Ali.
Título: Kinetic and toxicological effects of synthesized palladium(II) complex on snake venom (Bungarus sindanus) acetylcholinesterase
Fonte: J. venom. anim. toxins incl. trop. dis;27:e20200047, 2021. tab, graf.
Idioma: en.
Projeto: higher education commission of Pakistan.
Resumo: The venom of the krait (Bungarus sindanus), an Elapidae snake, is highly toxic to humans and contains a great amount of acetylcholinesterase (AChE). The enzyme AChE provokes the hydrolysis of substrate acetylcholine (ACh) in the nervous system and terminates nerve impulse. Different inhibitors inactivate AChE and lead to ACh accumulation and disrupted neurotransmission. Methods: The present study was designed to evaluate the effect of palladium(II) complex as antivenom against krait venom AChE using kinetics methods. Results: Statistical analysis showed that krait venom AChE inhibition decreases with the increase of Pd(II) complex (0.025-0.05 µM) and exerted 61% inhibition against the AChE at a fixed concentration (0.5 mM) of ACh. Kinetic analysis using the Lineweaver Burk plot showed that Pd(II) caused a competitive inhibition. The compound Pd(II) complex binds at the active site of the enzyme. It was observed that K m (Michaelis-Menten constant of AChE-ACh into AChE and product) increased from 0.108 to 0.310 mM (45.74 to 318.35%) and V max remained constant with an increase of Pd(II) complex concentrations. In AChE K Iapp was found to increase from 0.0912 to 0.025 µM (29.82-72.58%) and did not affect the V maxapp with an increase of ACh from (0.05-1 mM). K i (inhibitory constant) was estimated to be 0.029µM for snake venom; while the K m was estimated to be 0.4 mM. The calculated IC50 for Pd(II) complex was found to be 0.043 µM at constant ACh concentration (0.5 mM). Conclusions: The results show that the Pd(II) complex can be deliberated as an inhibitor of AChE.(AU)
Descritores: Bungarus
Venenos Elapídicos/toxicidade
Biologia Sintética
-Paládio
Acetilcolinesterase
Limites: Animais
Responsável: BR68.1 - Biblioteca Virginie Buff D'Ápice


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Id: biblio-1254710
Autor: Song, Wu; Tang, Yong; Wei, Lin; Zhang, Chi; Song, Danning; Li, Xueting; Jiang, Shuang.
Título: Protective effect of CD73 inhibitor α, ß-methylene ADP against amyloid-ß-induced cognitive impairment by inhibiting adenosine production in hippocampus
Fonte: Electron. j. biotechnol;48:53-61, nov. 2020. ilus, graf.
Idioma: en.
Projeto: Jilin Province Science and Technology Department.
Resumo: BACKGROUND: Alzheimer's disease (AD) is a chronic, progressive neurodegenerative disease. Recent studies have reported the close association between cognitive function in AD and purinergic receptors in the central nervous system. In the current study, we investigated the effect of CD73 inhibitor α, ß-methylene ADP (APCP) on cognitive impairment of AD in mice, and to explore the potential underlying mechanisms. RESULTS: We found that acute administration of Aß1­42 (i.c.v.) resulted in a significant increase in adenosine release by using microdialysis study. Chronic administration of APCP (10, 30 mg/kg) for 20 d obviously mitigated the spatial working memory impairment of Aß1­42-treated mice in both Morris water maze (MWM) test and Y-maze test. In addition, the extracellular adenosine production in the hippocampus was inhibited by APCP in Aß-treated mice. Further analyses indicated expression of acetyltransferase (ChAT) in hippocampus of mice of was significantly reduced, while acetylcholinesterase (AChE) expression increased, which compared to model group. We observed that APCP did not significantly alter the NLRP3 inflammasome activity in hippocampus, indicating that anti-central inflammation seems not to be involved in APCP effect. CONCLUSIONS: In conclusion, we report for the first time that inhibition of CD73 by APCP was able to protect against memory loss induced by Aß1­42 in mice, which may be due to the decrease of CD73-driven adenosine production in hippocampus. Enhancement of central cholinergic function of the central nervous system may also be involved in the effects of APCP.
Descritores: Difosfato de Adenosina/análogos & derivados
Doenças Neurodegenerativas/prevenção & controle
Hipocampo
Nucleotidases/antagonistas & inibidores
-Acetilcolinesterase
Difosfato de Adenosina/administração & dosagem
Doença de Alzheimer/prevenção & controle
Teste do Labirinto Aquático de Morris
Camundongos Endogâmicos C57BL
Limites: Animais
Masculino
Camundongos
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1279406
Autor: Lopez, Simon Miguel M; Aguilar, Jeremey S; Fernandez, Jerene Bashia B; Lao, Angelic Gayle J; Estrella, Mitzi Rain R; Devanadera, Mark Kevin P; Ramones, Cydee Marie V; Villaraza, Aaron Joseph L; Guevarra Junior, Leonardo A; Santiago-Bautista, Myla R; Santiago, Librado A.
Título: Neuroactive venom compounds obtained from Phlogiellus bundokalbo as potential leads for neurodegenerative diseases: insights on their acetylcholinesterase and beta-secretase inhibitory activities in vitro
Fonte: J. venom. anim. toxins incl. trop. dis;27:e20210009, 2021. tab, graf, ilus, mapas.
Idioma: en.
Resumo: Spider venom is a rich cocktail of neuroactive compounds designed to prey capture and defense against predators that act on neuronal membrane proteins, in particular, acetylcholinesterases (AChE) that regulate synaptic transmission through acetylcholine (ACh) hydrolysis - an excitatory neurotransmitter - and beta-secretases (BACE) that primarily cleave amyloid precursor proteins (APP), which are, in turn, relevant in the structural integrity of neurons. The present study provides preliminary evidence on the therapeutic potential of Phlogiellus bundokalbo venom against neurodegenerative diseases. Methods Spider venom was extracted by electrostimulation and fractionated by reverse-phase high-performance liquid chromatography (RP-HPLC) and characterized by matrix-assisted laser desorption ionization-time flight mass spectrometry (MALDI-TOF-MS). Neuroactivity of the whole venom was observed by a neurobehavioral response from Terebrio molitor larvae in vivo and fractions were screened for their inhibitory activities against AChE and BACE in vitro. Results The whole venom from P. bundokalbo demonstrated neuroactivity by inducing excitatory movements from T. molitor for 15 min. Sixteen fractions collected produced diverse mass fragments from MALDI-TOF-MS ranging from 900-4500 Da. Eleven of sixteen fractions demonstrated AChE inhibitory activities with 14.34% (± 2.60e-4) to 62.05% (± 6.40e-5) compared with donepezil which has 86.34% (± 3.90e-5) inhibition (p > 0.05), while none of the fractions were observed to exhibit BACE inhibition. Furthermore, three potent fractions against AChE, F1, F3, and F16 displayed competitive and uncompetitive inhibitions compared to donepezil as the positive control. Conclusion The venom of P. bundokalbo contains compounds that demonstrate neuroactivity and anti-AChE activities in vitro, which could comprise possible therapeutic leads for the development of cholinergic compounds against neurological diseases.(AU)
Descritores: Acetilcolinesterase
Venenos de Aranha/toxicidade
Neurotransmissores
Doenças Neurodegenerativas
-Técnicas In Vitro
Limites: Animais
Responsável: BR68.1 - Biblioteca Virginie Buff D'Ápice


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Id: lil-621312
Autor: Silveira, Sirlene; Lucena, Elvis Viana de; Pereira, Tuanny Fernanda; Garnés, Fabrícia Lorca dos Santos; Romagnolo, Mariza Barion; Takemura, Orlando Seiko; Laverde-Junior, Antonio.
Título: Atividade anticolinesterásica dos frutos de myrcianthes pungens (o Berg) d Legrand (myrtaceae) / Anticholinesterase activity of myrcianthes pungens (o Berg) d Legrand (myrtaceae) fruits
Fonte: Arq. ciências saúde UNIPAR;15(2), maio-ago. 2011. tab.
Idioma: pt.
Resumo: Os inibidores da enzima acetilcolinesterase (AChE) são uma das principais classes de medicamentos utilizadas no tratamento de sintomas de doenças neurodegenerativas como a doença de Alzheimer (DA), pois são capazes de elevar os níveis de acetilcolina no cérebro. Plantas têm sido uma excelente alternativa na busca de novas moléculas bioativas. No presente trabalho, extratos alcoólicos dos frutos de Myrcianthes pungens (O.Berg) D.Legrand (Myrtaceae), também conhecidos como guabijú ou guabiroba-açú, foram investigados quanto à capacidade de inibição de AChE in vitro por ensaio bioautográfico, utilizando o reagente Fast Blue Salt B. Foi observada a presença de pelo menos quatro diferentes substâncias com capacidade inibitória de AChE nos frutos verdes e maduros desta espécie. Duas das substâncias ativas foram caracterizadas como terpenos por meio de ensaios com reagentes específicos em cromatografia de camada delgada. Estes resultados correspondem ao primeiro relato da atividade de inibição de AChE em espécies do gênero Myrcianthes (Myrtaceae).

Inhibitors of the acetylcholinesterase enzyme (AChE) are one of the major classes of drugs used in the treatment of symptoms of neurodegenerative diseases like Alzheimer?s disease (AD), because they can increase the levels of acetylcholine in the brain. Plants have been an excellent alternative source of bioactive molecules. In the present study, alcoholic extracts of fruits of Myrcianthes pungens (O.Berg) D.Legrand (Myrtaceae), also known as ?guabijú? or ?guabiroba-açú?, were investigated for their ability to inhibit AChE in vitro in a bioautographic assay using Fast Blue Salt B reagent. The presence of at least four different substances capable of inhibiting AChE in unripe and ripe fruits of this species was observed. Two active substances were characterized as terpenes in assays using specific reagents with thin layer chromatography. These results are the first report of the AchE inhibition activity for species of Myrcianthes genus (Myrtaceae).
Descritores: Acetilcolinesterase
Myrtaceae
Inibidores Enzimáticos
-Preparações Farmacêuticas
Doenças Neurodegenerativas
Cérebro
Doença de Alzheimer
Responsável: BR513.1 - Biblioteca Central


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Id: biblio-950772
Autor: Zeb, Anwar; Sadiq, Abdul; Ullah, Farhat; Ahmad, Sajjad; Ayaz, Muhammad.
Título: Investigations of anticholinestrase and antioxidant potentials of methanolic extract, subsequent fractions, crude saponins and flavonoids isolated from Isodon rugosus
Fonte: Biol. Res;47:1-10, 2014. graf, tab.
Idioma: en.
Resumo: BACKGROUND: Based on the ethnomedicinal uses and the effective outcomes of natural products in various diseases, this study was designed to evaluate Isodon rugosus as possible remedy in oxidative stress, alzheimer's and other neurodegenerative diseases. Acetylecholinestrase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of crude methanolic extract (Ir.Cr), resultant fractions (n-hexane (Ir.Hex), chloroform (Ir.Cf), ethyl acetate (Ir.EtAc), aqueous (Ir.Aq)), flavonoids (Ir.Flv) and crude saponins (Ir.Sp) of I. rugosus were investigated using Ellman's spectrophotometric method. Antioxidant potential of I. rugosus was determined using DPPH, H2O2 and ABTS free radicals scavenging assays. Total phenolic and flavonoids contents of plant extracts were determined and expressed in mg GAE/g dry weight and mg RTE/g of dry sample respectively. RESULTS: Among different fractions Ir.Flv and Ir.Cf exhibited highest inhibitory activity against AChE (87.44 ± 0.51, 83.73 ± 0.64%) and BChE (82.53 ± 0.71, 88.55 ± 0.77%) enzymes at 1 mg/ml with IC50 values of 45, 50 for AChE and 40, 70 µg/ml for BChE respectively. Activity of these fractions were comparable to galanthamine causing 96.00 ± 0.30 and 88.61 ± 0.43% inhibition of AChE and BChE at 1 mg/ml concentration with IC50 values of 20 and 47 µg/ml respectively. In antioxidant assays, Ir.Flv, Ir.Cf, and Ir.EtAc demonstrated highest radicals scavenging activities in DPPH and H2O2 assays which were comparable to ascorbic acid. Ir.Flv was found most potent with IC50 of 19 and 24 µg/ml against DPPH and H2O2 radicals respectively. Whereas antioxidant activates of plant samples against ABTS free radicals was moderate. Ir.Cf, Ir.EtAc and Ir.Cr showed high phenolic and flavonoid contents and concentrations of these compounds in different fractions correlated well to their antioxidant and anticholinestrase activities. CONCLUSION: It may be inferred from the current investigations that the Ir.Sp, Ir.Flv and various fractions of I. rugosus are good sources of anticholinesterase and antioxidant compounds. Different fractions can be subjected to activity guided isolation of bioactive compounds effective in neurological disorders.
Descritores: Saponinas/análise
Flavonoides/análise
Extratos Vegetais/química
Inibidores da Colinesterase/análise
Isodon/química
Antioxidantes/análise
-Picratos/metabolismo
Acetilcolinesterase/efeitos dos fármacos
Saponinas/isolamento & purificação
Espectrofotometria/métodos
Ácidos Sulfônicos/metabolismo
Flavonoides/isolamento & purificação
Compostos de Bifenilo/metabolismo
Butirilcolinesterase/efeitos dos fármacos
Clorofórmio
Sequestradores de Radicais Livres/metabolismo
Estresse Oxidativo/efeitos dos fármacos
Concentração Inibidora 50
Isodon/classificação
Isodon/enzimologia
Componentes Aéreos da Planta/química
Misturas Complexas
Metanol
Benzotiazóis/metabolismo
Radicais Livres/análise
Hexanos
Peróxido de Hidrogênio/metabolismo
Medicina Tradicional
Acetatos
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-950785
Autor: Kamal, Zul; Ullah, Farhat; Ayaz, Muhammad; Sadiq, Abdul; Ahmad, Sajjad; Zeb, Anwar; Hussain, Abid; Imran, Muhammad.
Título: Anticholinesterse and antioxidant investigations of crude extracts, subsequent fractions, saponins and flavonoids of atriplex laciniata L: potential effectiveness in Alzheimer's and other neurological disorders
Fonte: Biol. Res;48:1-11, 2015. graf, tab.
Idioma: en.
Resumo: BACKGROUND: Atriplex laciniata L. was investigated for phenolic, flavonoid contents, antioxidant, anticholinesterase activities, in an attempt to explore its effectiveness in Alzheimer's and other neurological disorders. Plant crude methanolic extract (Al.MeF), subsequent fractions; n-hexane (Al.HxF), chloroform (Al.CfF), ethyl acetate (Al.EaF), aqueous (Al.WtF), Saponins (Al.SPF) and Flavonoids (Al.FLVF) were investigated for DPPH, ABTS and H2O2 free radical scavenging activities. Further these extracts were subjected to acetylcholinesterase (AChE) & butyrylcholinesterase (BChE) inhibitory activities using Ellman's assay. Phenolic and Flavonoid contents were determined and expressed in mg Gallic acid GAE/g and Rutin RTE/g of samples respectively. RESULTS: In DPPH free radicals scavenging assay, Al.FLVF, Al.SPF and Al.MeF showed highest activity causing 89.41 ± 0.55, 83.37 ± 0.34 and 83.37 ± 0.34% inhibition of free radicals respectively at 1 mg/mL concentration. IC50 for these fractions were 33, 83 and 82 µg/mL respectively. Similarly, plant extracts showed high ABTS scavenging potential, i.e. Al.FLVF (90.34 ± 0.55), Al.CfF (83.42 ± 0.57), Al.MeF (81.49 ± 0.60) with IC50 of 30, 190 and 70 µg/ml respectively. further, H2O2 percent scavenging was highly appraised in Al.FLVF (91.29 ±0.53, IC50 75), Al.SPF (85.35 ±0.61, IC50 70) and Al.EaF (83.48 ± 0.67, IC50 270 µg/mL). All fractions exhibited concentration dependent AChE inhibitory activity as; Al.FLVF, 88.31 ± 0.57 (IC50 70 µg/mL), Al.SPF, 84.36 ± 0.64 (IC50 90 µg/mL), Al.MeF, 78.65 ± 0.70 (IC50 280 µg/mL), Al.EaF, 77.45 ± 0.46 (IC50 270 µg/mL) and Al.WtF 72.44 ± 0.58 (IC50 263 µg/mL) at 1 mg/mL. Likewise the percent BChE inhibitory activity was most obvious in Al.FLVF 85.46 ± 0.62 (IC50 100 µg/mL), Al.CfF 83.49 ± 0.46 (IC50 160 µg/mL), Al.MeF 82.68 ± 0.60 (IC50 220 µg/mL) and Al.SPF 80.37 ± 0.54 (IC50 120 µg/mL). CONCLUSIONS: These results stipulate that A. laciniata is enriched with phenolic and flavonoid contents that possess significant antioxidant and anticholinestrase effects. This provide pharmacological basis for the presence of compounds that may be effective in Alzheimer's and other neurological disorders.
Descritores: Saponinas/metabolismo
Flavonoides/metabolismo
Extratos Vegetais/farmacologia
Inibidores da Colinesterase/farmacologia
Atriplex/química
Doença de Alzheimer/tratamento farmacológico
Antioxidantes/farmacologia
-Fenóis/análise
Fenóis/metabolismo
Acetilcolinesterase/metabolismo
Saponinas/isolamento & purificação
Espectrofotometria
Ácidos Sulfônicos/metabolismo
Flavonoides/análise
Butirilcolinesterase/metabolismo
Inibidores da Colinesterase/isolamento & purificação
Sequestradores de Radicais Livres/farmacologia
Estresse Oxidativo/efeitos dos fármacos
Concentração Inibidora 50
Benzotiazóis/metabolismo
Medicina Tradicional
Antioxidantes/isolamento & purificação
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1146424
Autor: Silva, Letícia Siqueira da; Porfiro, Cinthia Alves; Silva, Fabiano Guimarães; Rodrigues, Agna Rita dos Santos; Pereira, Paulo Sérgio.
Título: Acetylcholinesterase and α-Amylase inhibitors from Mouriri elliptica Martius leaf extract / Inibidores da acetilcolinesterase e α-amilase do extrato da folha de Mouriri elliptica Martius
Fonte: Biosci. j. (Online);36(2):578-590, 01-03-2020. ilus, tab, graf.
Idioma: en.
Resumo: Population growth has raised food production, and new sources are needed to increase quantity and quality of agricultural products. Carbamates and organophosphates are insecticide classes used worldwide as acetylcholinesterase (AChE) inhibitors. Plants have a natural resistance to insects, which can be employed in pest control as a new alternative to reduce the use of chemicals. An alternative may be the use of α-amylase inhibitors, which are digestive enzymes that impair pest species growth and development. Another would be acetylcholinesterase inhibitors since they damage the normal functioning of the central and peripheral nervous system, by releasing high concentrations of acetylcholine in cholinergic synapses. This substance accumulation increases stimulations that lead to behavioral changes, asphyxia, hyperactivity, and death. Botanical agrochemicals are believed to have advantages over synthetic ones, as they are rapidly degraded in the environment. In this scenario, plants have played an important role in pest control as sources of interest for the synthesis of new molecules for agricultural use. The present study evaluated acetylcholinesterase and α-amylase inhibition by microplate method, from leaf extracts of Mouriri elliptica Martius with different polarities.

O crescimento populacional tem aumentado a quantidade de produção alimentícia, sendo necessárias novas fontes para o aumento da quantidade e qualidade dos produtos agrícolas. Os carbamatos e organofosforados são classes de inseticidas utilizadas em todo o mundo, são inibidores da acetilcolinesterase (AChE). Os vegetais possuem uma resistência natural aos insetos, e esse método de resistência pode ser utilizado no controle das pragas como uma nova alternativa para redução do uso de inseticidas químicos, tais como os inibidores da α-amilase, enzima digestiva, a qual sua inibição prejudica o crescimento e desenvolvimento de espécies de pragas. E os inibidores da acetilcolinesterase que danificam o funcionamento normal do Sistema Nervoso Central e Periférico, através de elevadas concentrações da acetilcolina que ficam depositadas nas sinapses colinérgicas. Este acúmulo de ACh provoca uma grande estimulação que leva á alterações comportamentais, asfixia, hiperatividade e a morte. Estudos já realizados mostraram que os agrotóxicos botânicos têm vantagens sobre os sintéticos, sendo degradados rapidamente no meio ambiente. Neste cenário os vegetais têm desempenhado um importante papel no controle de pragas, através da síntese de novas moléculas para uso na agricultura. O presente trabalho avaliou a inibição das enzimas acetilcolinesterase e α-amilase através do método da microplaca a partir dos extratos das folhas de Mouriri elliptica Martius em diferentes polaridades.
Descritores: Acetilcolinesterase
Controle de Pragas
Inibidores da Colinesterase
alfa-Amilases
-Praguicidas
Produção de Alimentos
Cromatografia
Agroquímicos
Produtos Agrícolas
Pradaria
Responsável: BR396.1 - Biblioteca Central


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Id: biblio-960654
Autor: Yolima Nitola, Ledy; Ricardo Muñoz, Diego; Javier Patiño, Oscar; Angélica Prieto, Juliet.
Título: Caracterización fitoquímica y evaluación de actividad inhibitoria sobre acetilcolinesterasa de hojas de Piper pesaresanum C. DC / Phytochemical characterization and evaluation of the inhibitory activity of Piper pesaresanum C. DC leaves against acetylcholinesterase
Fonte: Rev. cuba. plantas med;21(4), oct.-dic. 2016. tab.
Idioma: es.
Resumo: Introducción: el género Piper perteneciente a la familia Piperaceae es de gran importancia económica debido a sus aplicaciones a nivel alimenticio, industrial y medicinal. Especies de este género son conocidas popularmente como cordoncillos y se caracterizan porque presentan un amplio espectro de actividades biológicas, entre las que se encuentra el efecto neuroprotector, que está asociado al tratamiento de enfermedades neurodegenerativas como el Alzheimer. En Colombia existen muchas especies a las cuales no se les han desarrollado estudios investigativos, tal es el caso de Piper pesaresanum C. DC. Objetivo: caracterizar química y biológicamente el extracto etanólico de hojas de P. pesaresanum mediante un estudio fitoquímico biodirigido y evaluar la actividad inhibitoria sobre acetilcolinesterasa. Métodos: a partir del extracto etanólico de hojas maduras de P. pesarenasum se realizó un estudio químico biodirigido para aislar e identificar las sustancias responsables de la actividad inhibitoria sobre acetilcolinesterasa. La evaluación de la actividad inhibitoria sobre acetilcolinesterasa se realizó por autografía directa empleando el método de Ellman. Adicionalmente se realizó un tamizaje fitoquímico preliminar mediante pruebas de coloración y precipitación llevadas a cabo en vía húmeda y cromatografía en capa delgada. Resultados: el análisis fitoquímico preliminar sugiere la presencia de terpenos, esteroides, fenoles y cumarinas. La evaluación de la actividad inhibitoria sobre acetilcolinesterasa permitió evidenciar zonas claras de inhibición en las fracciones de éter de petróleo (EP) y cloroformo (CHCl3). El estudio fitoquímico biodirigido condujo al aislamiento e identificación por primera vez para la especie del ácido 4-metoxi-3,5-di(3'-metil-2'-butenil) benzoico. Conclusiones: el estudio químico y de actividad biológica llevado a cabo en la especie P. pesaresanum permitió identificar al ácido 4-metoxi-3,5-di(3'-metil-2'-butenil) benzoico como uno de los compuestos responsables de la actividad inhibitoria sobre acetilcolinesteras(AU)

Introduction: The genus Piper, from the Piperaceae family, has great economic importance, due to its uses on a nutritional, industrial and medicinal level. The species in this genus are commonly known as peppers, and are characterized by a broad range of biological activities, including a neuroprotective effect associated with the treatment of neurodegenerative conditions such as Alzheimer's disease. Many of the species growing in Colombia have not been studied. Such is the case with Piper pesaresanum C. DC. Objective: Carry out a chemical and biological characterization of the ethanolic extract of P. pesaresanum leaves by means of a bioguided phytochemical study and evaluate inhibitory activity on acetylcholinesterase. Methods: A bioguided chemical study was conducted of the ethanolic extract of P. pesarenasum mature leaves to isolate and identify the substances responsible for inhibitory activity on acetylcholinesterase. Evaluation of inhibitory activity on acetylcholinesterase was based on direct autography using the Ellman method. Preliminary phytochemical screening was also performed by means of wet color and precipitation tests, and thin-layer chromatography. Results: Preliminary phytochemical analysis suggests the presence of terpenes, steroids, phenols and coumarins. Evaluation of inhibitory activity on acetylcholinesterase revealed clear-cut inhibition areas in petroleum ether (PE) and chloroform (CHCl3) fractions. The bioguided phytochemical study led to isolation and identification of 4-methoxy-3.5-di(3'-methyl-2'-butenyl) benzoic acid for the first time in the study species. Conclusions: Chemical study and evaluation of the biological activity of the species P. pesaresanum led to identification of 4-methoxy-3.5-di(3'-methyl-2'-butenyl) benzoic acid as one of the compounds responsible for inhibitory activity on acetylcholinesterase(AU)
Descritores: Piperaceae/efeitos dos fármacos
Preparações de Plantas/uso terapêutico
Doença de Alzheimer/tratamento farmacológico
-Acetilcolinesterase
Cromatografia em Camada Delgada/métodos
Colômbia
Limites: Humanos
Responsável: CU1.1 - Biblioteca Médica Nacional


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Id: biblio-1146381
Autor: CHAVES, Valesca de Souza; MARCON, Jaydione Luiz; DUNCAN, Wallice Paxiúba; ALVES-GOMES, José Antônio.
Título: Acute toxicity of a deltamethrin based pesticide (DBP) to the Neotropical electric fish Microsternarchus cf. bilineatus (Gymnotiformes)
Fonte: Acta amaz;50(4):355-362, out. - dez. 2020.
Idioma: en.
Resumo: A deltametrina é um inseticida piretróide amplamente utilizado no controle de pragas na agricultura brasileira. O uso intensivo e desordenado desse pesticida na Amazônia pode carreá-lo aos ecossistemas aquáticos de várias maneiras, mas principalmente por escoamento e lixiviação. O presente estudo foi concebido para determinar a toxicidade aguda (LC50) de um pesticida à base de deltametrina (PBD) e caracterizar seus efeitos sobre dois biomarcadores bioquímicos, a glutationa-S-transferase (GST) e a acetilcolinesterase (AChE), em tecidos do peixe elétrico Microsternarchus cf. bilineatus. Os peixes foram expostos a concentrações de 1, 2, 3, 4 e 5 µg L-1 de PBD por até 96 horas. Para cada tratamento, foi analisada a atividade absoluta das enzimas GST (músculo e fígado) e AChE (músculo e tecido nervoso). A CL50-96 h para Microsternarchus cf. bilineatus foi de 2,15 µg L-1, a menor concentração registrada para um peixe amazônico até o momento. Nenhuma das concentrações testadas deste inseticida afetou a atividade da AChE para o período de exposição testado. Um aumento significativo da atividade de GST no músculo foi detectado somente para as concentrações de 2 e 3 µg L-1. (AU)
Descritores: Acetilcolinesterase
Biomarcadores
Glutationa S-Transferase pi
Inseticidas
Responsável: BR6.1 - BCS - Biblioteca de Ciências da Saúde


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Id: lil-252056
Autor: Rivero, Exila; Rincón, Rita; González, Soraya; Rojas, Maritza.
Título: Exposición ocupacional a plaguicidas en una comunidad agrícola del estado Lara, Venezuela / Occupational exposure a pesticides in a agricultural community of the estado Lara, Venezuela
Fonte: Salud trab. (Maracay);5(2):93-98, jul. 1997. tab.
Idioma: es.
Resumo: Se estudió una comunidad agrícola de Venezuela, con el objetivo de investigar la exposición ocupacional a plaguicidas. Se evaluaron 37 agricultores expuestos a plaguicidas (GE) y 17 trabajadores no expuestos (GNE), mediante un cuestionario, examen médico y determinación de la actividad de la acetilcolinesterasa eritrocítica (ACE-E), por el Método de Ellman modificado. Se utilizaron medidas de tendencia central, dispersión, correlación de Pearson, regresión simple, T de Student. El nivel de significancia fue fijada a 5 por ciento (p<0,05). El promedio de la ACE-E, corregida por hemoglobina en el GNE fue de 32,2U/gHbñ2,2 y en el GE de 31,3U/gHBñ2,8(p>0,05) del cual el 5,4 por ciento presentaron valores menores de 26U/gHb. El mayor procentaje de plaguicidas utilizado fue: organofosforados (OF) 91,8 por ciento; carbomatos 37,8 por ciento, piretroides 32,4 por ciento. Los síntomas referidos con la exposición a OF fueron: mareos 45,9 por ciento, sudoración 45,9 por ciento, cefaleas 35,1 por ciento, salivación 18,9 por ciento. 29,4 por ciento del GE refirió haber presentado previo al estudio, intoxicación por OF en por lo menos una ocasión. Aunque los valores de ACE-E en el GE fueron normales, hubo una tendencia hacia el límite inferior, lo cual podría inferir la ocurrencia de absorción de OF o carbamatos, sin que la inhibición de la ACE-E alcance niveles suficientemente bajos para que sea significativa. Existe riesgo implícito por el uso elevado de OF, la escasa protección personal utilizada, inadecuada disposición de desechos, falta de información precisa y oportuna, al no existir programas de extención agrícola en el sector estudiado(AU)

A Venezuelan agricultural community was evaluated to determine the degree of occupational exposure to pesticides of its workers. Thirty seven (37) farmers exposed to pesticides) exposed group, EG) and seventeen farmworkers from the same region who were no exposed, (NEG) were studied by using a modified Ellman Method. To do this study a questionnaire, a medical examination, and erythrocyte cholinesterase (ChE) activity determination were used. Central trend measurements, variations, a Pearson correlation, a simple regression, and a student test were employed for the statistical analyses. The significance level was set at 5% (p <0.05). The ChE average, corrected for hemoglobin in the NEG, was 32,5 U/g Hb ± 2,2 and in the EG it was 31,3 U/g Hb ± 2,8 (p > 0.05). In the latter group 5,4% had values of less than 26 U/g Hb: the normal value being (NV) > 26 U/g Hb. The highest percentage of pesticides used were organophosphates (OP) (91.8%), carbamates 37,8 , and pyrethroids 32,4%. The symptoms referable to Ops were dizziness 45,9%, sweating 45,9%, cephalea 35,1% and, salivation 18,9%. Prior to the study, 29,4% of the EG showed, poisoning produced by OP on at least one occasion. Although the ChE values I the EG were within the normal range, a tendency toward the lower limit was observed; therefore, it could be inferred that the absorption of OP or carbamate occurred without a significant decrease in the ChE activity. There is undoubtedly a risk in using great amounts of OP due to the lack of providing accurate information to those concerned; this is due to the fact that an agricultural extension program is non-existent in the region under study(AU)
Descritores: Praguicidas
Envenenamento
Acetilcolinesterase
Carbamatos
Risco
Exposição Ocupacional
Fazendeiros
Categorias de Trabalhadores
-Sinais e Sintomas
Inquéritos e Questionários
Limites: Humanos
Tipo de Publ: Relatos de Casos
Responsável: VE1.1 - Biblioteca Humberto Garcia Arocha



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