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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Effect of Pyridostigmine on Heart Rate Recovery After Exercise in Trained Athletes and Sedentary Adults

Dewland, Thomas Andrew 10 November 2006 (has links)
Acetylcholinesterase inhibition with pyridostigmine has been previously studied in patients with congestive heart failure (CHF), but the effects of this medication on heart rate recovery after exercise and other indices of parasympathetic activity in populations with greater baseline vagal tone has not been fully characterized. Ten healthy, sedentary adults and ten aerobically trained athletes were enrolled in a prospective, double blind, randomized placebo controlled crossover trial. All study subjects were treated with a single dose of oral pyridostigmine 30 mg and matching placebo on separate days. Heart rate variability (HRV) at rest and heart rate recovery (HRR) at one minute after maximal cardiopulmonary exercise stress testing were measured. In sedentary adults, pyridostigmine significantly lowered resting heart rate (mean (SEM) 58.1 (2.4) beats/min versus 66.7 (4.0) beats/min, p = 0.01), increased HRR at one minute (45.1 (2.8) beats/min versus 40.7 (3.4) beats/min, p = 0.02), and lowered both resting mean arterial pressure (80.3 (2.0) mm Hg versus 84.3 (2.7) mm Hg, p = 0.02) and peak exercise mean arterial pressure (103.3 (3.1) mm Hg versus 108.8 (3.2) mm Hg, p < 0.01). In trained athletes, resting heart rate and HRR at one minute were unaffected by pyridostigmine dosing, although a significant increase in VO2 max was observed with the study drug (54.8 (3.5) ml/kg/min versus 53.3 (3.6) ml/kg/min, p = 0.02). Pyridostigmine did not change indices of heart rate variability in either cohort. The difference in resting heart rate and HRR responses to pyridostigmine between athletes and sedentary controls likely reflects training induced modifications of the autonomic nervous system. The inability of acetylcholinesterase inhibition to affect HRV in either sedentary adults or athletes further suggests the improved HRR previously observed in CHF patients treated with pyridostigmine is secondary to parasympathetic augmentation.
72

On novel functions of cholinesterases implications for the development of two model organisms (Gallus gallus and Danio rerio) and for human recombinant mutant enzymes /

Allebrandt, Karla Viviani. Unknown Date (has links)
Techn. University, Diss., 2005--Darmstadt.
73

Chlorpyrifos uygulanmasının akut dönemde hipokampusta NMDA 2A ve 2B reseptörleri düzeyine etkisinin incelenmesi /

Karakoyun, İnanç. Gültekin, Fatih. January 2005 (has links) (PDF)
Tez (Tıpta Uzmanlık) - Süleyman Demirel Üniversitesi, Tıp Fakültesi, Biyokimya Anabilim Dalı, 2005. / Kaynakça var.
74

A calcitonin gene-related peptide-induced signaling pathway directs the synaptic expression of collagen-tail subunit (ColQ) of acetylcholinesterase in muscle /

Ting, Kin Lai. January 2005 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references (leaves 151-171). Also available in electronic version.
75

Die nicht-cholinerge Funktion der Azetylcholinesterase in dopaminergen Gebieten des ZNS in gesunden, pathologischen und sich entwickelnden Systemen The non-cholinergic function of acetylcholinesterase in the dopaminergic areas of the CNS in healthy, pathological and developing systems /

Heiland, Bettina. January 2002 (has links)
Darmstadt, Techn. Univ., Diss., 2002. / Dateien im PDF-Format
76

Muscular activity regulates the expression of ColQ subunit of acetylcholinesterase : a signaling pathway mediated by Ca2̳+̳/ calmodulin-dependent protein kinase II /

Lau, Faye. January 2007 (has links)
Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / On t.p. "2̳+̳" is superscript. Includes bibliographical references (leaves 137-155). Also available in electronic version.
77

Biologická aktivita sekundárních metabolitů rostlin II. Alkaloidy Narcissus jonquilla L. / Biological aktivity of secondary plants metabolites II. Alkaloids of Narcissus jonquilla L.

Jílek, Lukáš January 2015 (has links)
Jílek L.: The biological activity of secondary plants metabolites II. Alkaloids of Narcissus jonquilla L. Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2015, pp. 74. The aim of the diploma thesis was a preparation of alkaloid extracts to identification of alkaloid patterns and measure cholinesterase inhibitory activity. This activity is useful for treating Alzheimer's disease. Alkaloid extracts of seven Narcissus jonquilla L. (Amaryllidaceae) varieties (Bella Estrella, Bell Song, Fruit Cup, Hill Star, Chit Chat, Martinette, Dick Sickel) were studied with respect to their acetylcholinesterase (HuAChE) and butyrylcholinesterase (HuBuChE) inhibitory activity and alkaloid patterns. Thirteen different alkaloids were identified from their mass spectra and retention times. All samples exhibited content of tazettine, most samples contained lycoramine and galanthamine. Promising HuAChE inhibition activity was demonstrated by Narcissus jonquilla L. cv. Bell Song with IC50 values of 6,19 ± 0,85 μg/mL. The strongest inhibitory activity against HuBuChE was detected in extract from Narcissus jonquilla L. cv. Bella Estrella with IC50 value of 18,39 ± 1,51 μg/mL. Keywords: Alzheimer's disease, Amaryllidaceae, Narcissus, GC/MS,...
78

Vývoj insekticidů inhibující acetylcholinesterasu / Development of insecticides inhibiting acetylcholineseterase

Mányová, Brigita January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Brigita Mányová Supervisor: PharmDr. Marie Vopršalová, CSc. Supervisor-specialist: PharmDr. Vendula Hepnarová, Ph.D. Title of diploma thesis: Development of insecticides inhibiting acetylcholineseterase Pest insects cause problems and damage all over the world. They are vectors of serious diseases such as malaria, dengue fever, yellow fever, Zika virus disease and chikungunya disease. They cause huge damage to agricultural crops and are annoying to everyday life in living spaces. The aim of this diploma thesis was in vitro testing of selected compounds from the group of bis-isoquinoline and bispyridinium acetylcholinesterase inhibitors as potential insecticides. Another goal was also to create relationships between structure and effect. The ability of these compounds to inhibit both human (hAChE) and fly acetylcholinesterase (MdAChE) was evaluated. The modified Ellman spectrophotometric method was used. The half inhibitory concentration (IC50) values were obtained for both enzymes and the selectivity indexes (SI) were then calculated. Compounds having IC50s in micromolar or nanomolar range and exhibiting selectivity for MdAChE were most desirable. During the testing of these inhibitors, three...
79

Recuperação de alevinos de pacu (Piaractus mesopotamicus) e tilápia (Oreochromis niloticus) sobreviventes à intoxicação aguda por fipronil / Recovery of fingerlings of pacu (Piaractus mesopotamicus) and tilapia (Oreochromis niloticus) survivors from acute intoxication by fipronil

Ignácio, Naiara Fernanda [UNESP] 25 May 2018 (has links)
Submitted by Naiara Fernanda Ignácio (naiaraignacio@yahoo.com.br) on 2018-07-23T04:19:42Z No. of bitstreams: 1 Tese de doutorado_ Naiara Fernanda Ignácio.pdf: 3478646 bytes, checksum: ad5f958489e90a28e31d1a3342b3eb4d (MD5) / Approved for entry into archive by Karina Gimenes Fernandes null (karinagi@fcav.unesp.br) on 2018-07-23T10:41:27Z (GMT) No. of bitstreams: 1 ignacio_nf_dr_jabo.pdf: 3478646 bytes, checksum: ad5f958489e90a28e31d1a3342b3eb4d (MD5) / Made available in DSpace on 2018-07-23T10:41:27Z (GMT). No. of bitstreams: 1 ignacio_nf_dr_jabo.pdf: 3478646 bytes, checksum: ad5f958489e90a28e31d1a3342b3eb4d (MD5) Previous issue date: 2018-05-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivou-se avaliar a capacidade de recuperação de alevinos de peixes das espécies de cativeiro pacu (Piaractus mesopotamicus) e tilápia (Oreochromis niloticus) após a intoxicação aguda com fipronil. A capacidade de recuperação foi avaliada nos peixes sobreviventes as concentrações de fipronil (Regent® 800WG) (0,56; 0,59; 0,61 e 0,64 mg.L-1 para o pacu; e 0,9; 0,11; 0,15 e 0,20 mg.L-1 para a tilápia) que causaram aproximadamente 10, 30, 50 e 70% de mortalidade após 24 horas de exposição aguda. Os peixes sobreviventes foram transferidos para água limpa. As avaliações foram realizadas no dia da transferência para a água limpa, e aos 15 e 30 dias de recuperação. Foram avaliadas as lesões em tecidos de brânquias, fígado e rins, e a atividade da enzima acetilcolinesterase (AChE) no cérebro e no músculo. Os sinais observados foram natação errática, espasmos musculares e mudança de coloração. Após 24 horas de exposição aguda, o fipronil, nas concentrações avaliadas, causou lesões estruturais nas brânquias, fígado e rins dos peixes, entre 70 e 73% de inibição da atividade da AChE no cérebro e entre 20 e 35% da AChE no músculo. Os peixes se recuperaram completamente dos sinais de intoxicação no terceiro dia. Aos 30 dias de recuperação, os peixes das duas espécies se recuperaram das lesões nos tecidos das brânquias, fígado e rins causadas pelo fipronil em concentração nas águas de até 0,61 mg.L-1 para o pacu, que causa até 54,2 % mortalidades; e de até 0,15 mg.L-1 para a tilápia, que causa até 46,7% de mortalidade. Em concentrações superiores a estas, o fipronil causou maior mortalidade e os peixes não se recuperaram totalmente. Os 30 dias em água limpa não são suficientes para a recuperação total da atividade da AChE, o que não altera o peso corpóreo. Portanto, os limites de aceitabilidade de inibição da atividade da AChE após 24 horas de exposição aguda ao fipronil é de 70% no cérebro dos peixes de ambas as espécies, 30% no músculo de pacu e 22% no da tilápia. As concentrações de fipronil não alteram as variáveis de qualidade de água. / The aim of this study was to evaluate the recovery capacity of juvenile fishes of the species pacu (Piaractus mesopotamicus) and tilapia (Oreochromis niloticus) after acute intoxication with fipronil. Recovery capacity was evaluated in fishes survivors from fipronil concentrations (Regent® 800WG) (0,56; 0,59; 0,61 e 0,64 mg.L-1 para for pacu; e 0,9; 0,11; 0,15 e 0,20 mg.L-1 for tilápia) in water that caused about 10, 30, 50 and 70% of mortality after 24 hours of acute exposure. The survivors were transferred to clean water. The evaluations were done on the day of transfer to clean water, and at 15 and 30 days of recovering. Damages were evaluated in gills, liver and kidneys tissues and the enzyme acetylcholinesterase (AChE) activity in the brain and muscle. The signs observed were erratic swimming, muscle spasms and color change. After 24 hours of acute exposure, fipronil at the tested concentrations causes histological damages in the gills, liver and kidneys of the fishes, 70 to 73% inhibition of AChE activity in the brain and between 20 and 35% in AChE in the muscle. The fishes recover completely from the intoxication signs on the third day. At 30 days of recovering, fishes from both species recovered from the damage in gills, liver and kidneys caused by fipronil at concentrations up to 0.61 mg.L-1 for pacu, which cause up to 54.2% of mortality; and up to 0.15 mg.L-1 for tilapia, which cause up to 46.7% of mortality. In higher concentrations than these, fipronil causes higher mortalities and the fishes do not recover fully. The 30 days in clean water are not enough for the total recovery of AChE activity, which does not change the body weight. Therefore, the acceptability of inhibition limit of AChE activity after 24 hours of acute fipronil exposure is 70% in fish brain of both species, 30% in pacu muscle and 22% in tilapia muscle. Fipronil concentrations do not alter the water quality variables.
80

Preparação e caracterização de biossensores baseado na eletrocodeposição de grafeno/polipirrol/acetilcolinesterase para determinação de pesticidas em amostras de frutas e vegetais

Camargo, João Pedro Corrêa January 2017 (has links)
Orientador: Ivana Cesarino / Abstract: A new biosensor was developed by a simple electrocodeposition of reduced graphene oxide (rGO), polypyrrole (PPy) and the enzyme acetylcholinesterase (AChE) on surface of platinum (Pt) electrode. In potential range of -0.2 to +0.5 V vs. Ag/AgCl/KCl (3.0 mol L-1), using differential pulse voltammetry (DPV), it was observed a process in + 0.1 V and this corresponds to the dimerization of electrochemical oxidation products of thiocholine, resulting in ditio-bis-choline. The biosensor developed was evaluated using DPV in the analysis of carbaryl, which inhibits the AChE enzyme action. The best results achieved were with the followings optimized conditions: 75 mV pulse amplitude, step potential of 4 mV, and a phosphate buffer solution (PBS) 0.2 mol L-1 and pH 6.0. Using these parameters was observed a linear response to carbaryl in a range of 0.1 to 0.5 µmol L-1, with a detection limit of 11.6 nmol L-1 (2.3 µg/kg), which is an appropriate limit for determination of carbaryl in the cultures which these pesticide is applied, considering the maximum reside limit allowed by Brazilian legislation. The biosensor proposed, Pt/rGO/PPy/AChE, was applied successfully in the determination of carbaryl in samples of cabbage and tomato. / Resumo: Um novo biossensor foi desenvolvido baseado na simples eletrocodeposição do óxido de grafeno reduzido (rGO), polipirrol (PPy) e da enzima acetilcolinesterase (AChE) na superfície do eletrodo de platina (Pt). No intervalo de potencial -0,2 a +0,5 V vs. Ag/AgCl/KCl (3,0 mol L-1), utilizando voltametria de pulso diferencial (DPV), observou-se um processo em +0,1 V e este corresponde a dimerização dos produtos de oxidação eletroquímica da tiolcolina, formando ditio-bis-colina. O biossensor desenvolvido foi avaliado utilizando DPV na análise do pesticida carbaril, o qual inibe a ação da enzima AChE. Os melhores resultados obtidos foram com as seguintes condições otimizadas: 75 mV amplitude de pulso, incremento de potencial de 4 mV, e uma solução tampão fosfato (PBS) 0,2 mol L-1 pH 6,0. Usando tais parâmetros observou-se uma resposta linear para o carbaril no intervalo de 0,1 a 0,5 mol L-1, com um limite de detecção de 11,6 nmolL-1 (2,3 µg/kg), que é um limite adequado para determinar carbaril nas culturas em que este pesticida é aplicado considerando o limite máximo de resíduo permitido pelas legislações brasileiras. O biossensor proposto, Pt/rGO/PPy/AChE, foi aplicado com sucesso na determinação de carbaril em amostras de tomate e repolho. / Mestre

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