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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.
51

Differential Response of Speech-Anxious Repressors and Sensitizers to Systematic Desensitization and Rational-Emotive Therapy

Beck, Karen Eileen 12 1900 (has links)
There is a scarcity of objective criteria upon which to select among the available therapies for those most likely to benefit specific patients. Comparative research has suggested that the outcomes of alternative and competitive therapies are equivalent. There are few facts available concerning which patients benefit most from even the more popular therapies. The purpose of this study was to find a type of patient for which differential improvement could be predicted. Neither therapy decreased checklist scores or increased speaking time significantly more than the other. Repressors and sensitizers responded equally to therapy. When dropout rates were analyzed there were also no significant differences between the therapies or between repressors and sensitizers. When posttherapy scores from both therapies were compared to pretherapy scores, no significant changes were found. The latter finding was important for understanding the absence of support for the hypotheses. Since the subjects did not improve as a result of either desensitization or rational-emotive therapy, there was no opportunity to observe the hypothesized differential changes. Given this hindsight, it was concluded that speech anxiety may not be a desirable disorder with which to study the prediction that repression-sensitization is related to the outcome of rational-emotive therapy and desensitization. It was recommended that future research of this relationship utilize a disorder for which therapeutic effectiveness is more firmly established.
52

Shareholder reaction to corporate eco-harmful behaviour: a cross-country comparison between Germany and China

IJmker, Sander January 2016 (has links)
In this study, the difference between shareholder reactions to eco-harmful behaviour by firms in China and Germany are being researched. Previous research has focused on shareholder reaction in developed countries, especially the US. What remains unknown is whether shareholders in developing countries have adopted the same norms concerning the environment as shareholders in developed countries. Institutional theory, legitimacy theory and desensitization theory are examined in this study. An event study was conducted with an [-1,1] and [-1,3] event window surrounding the announcement of eco-harmful behaviour by firms. Events were drawn from relevant news articles and environmental databases. In total 43 events have been discovered over the years 2007 to 2015. Overall, results indicate that the decrease in share prices is not significantly different from zero. However, when comparing China and Germany, evidence is found that Chinese firms are punished more severely than German firms when corporations harm the environment. Contrary to expectations, it can be concluded that the institutionalization of environmental norms has taken place in China, either through internal or global pressures.
53

An integrative approach to narrative therapy and eye movement desensitization and reprocessing (EMDR)

De Villiers, Elizabeth Fredericka 04 1900 (has links)
Thesis (MEdPsych)--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: As I engaged in a therapy journey with a single client, the possibilities for research on the integrative use of narrative therapy and EMDR unfolded. I investigated recent literature and realised that much had been written about narrative therapy as single approach to therapy within the postmodern paradigm. There was also extensive writing on EMDR and its integrative use with other therapies in assisting people who struggle with upsetting memories of trauma. Since I was unable to find any literature to date on the integrative use of narrative therapy and EMDR, I realized that there was much to be discovered and learned on such an integrative research journey. The client's experiences and descriptions of overwhelming emotional distress (as the problem in her life) during the process of integration was the main focus of this qualitative case study. During our therapy conversations knowledges were gathered and deconstructed. Video or tape recordings, photographs, work with clay, sketches, letters and other documents were useful in keeping track of the research journey. A reflecting team and the participation of the client's boyfriend contributed and enriched both the therapy and research journeys. / AFRIKAANSE OPSOMMING: Tydens terapeutiese werk met 'n enkele kliënt het die moontlikhede van navorsing oor die integrasie van narratiewe terapie en EMDR vir my 'n werklikheid geword. Ek het onlangse navorsing bestudeer en besef dat narratiewe terapie as 'n enkele benadering tot terapie binne die post-moderne paradigma, al 'n geruime tyd lank nagevors is. Daar bestaan ook literatuur oor EMDR en die integrasie daarvan met ander terapeutiese benaderings in die ondersteuning van persone wat probleme ondervind met ontstellende herinnerings van trauma. Aangesien ek tot op hede geen literatuur oor die integrasie van narratiewe terapie en EMDR kon vind nie, het ek vermoed dat 'n navorsingsreis op hierdie terrein verskeie ontdekkings en die ontginning van nuwe kennis moontlik sou maak. Die fokus van hierdie kwalitatiewe gevallestudie val op die kliënt se belewing en beskrywings van oorweldigende emosies (as probleem in haar lewe) tydens die terapeutiese integrasieproses. Waarhede of kennis is tydens terapiegesprekke versamel en gedekonstrueer. Video- of bandopnames, foto's, kleiwerk, sketse, briewe en ander dokumente was waardevol om die koers van die navorsingsreis aan te dui. Insette en deelname van 'n refekterende span, asook die kliënt se kêrel, het beide die terapie- en navorsingsreise verryk en uitgebrei.
54

If It Feels Good, View It: Selective Exposure and Desensitization Moderate the Association Between Video Gameplay and Pleasure-Oriented Aggression

Jabr, Mejdy M 16 December 2016 (has links)
A number of studies have indicated that violent video gameplay is associated with higher levels of aggression, and desensitization to violent content contributes to this association. Utilizing a rapid serial visual presentation (RSVP) task, the current study used event-related potentials (ERPs) to investigate selective attention (N1 activation), cognitive control (N2 activation), and desensitization (P3 activation) as neurocognitive mechanisms potentially underlying the association between gameplay and subtypes of aggression. Results showed video game players and non-players differed significantly in brain activation when engaged with violent imagery. N1 and P3 amplitude moderated the association between gameplay and pleasure-oriented aggression. Follow-up analyses further revealed that individuals who play games for many hours and show large N1 activation (high selective attention) in the face of violence have small P3 activation (heightened desensitization). Thus, our results suggest that selective attention to violent content and subsequent desensitization effects moderate the association between video gameplay and aggression.
55

Mexican Americans: Systematic Desensitization of Racial Emotional Responses

Fernandez, Peter, 1961- 05 1900 (has links)
To determine whether or not systematic desensitization treatment would produce a significant reduction in negative affect evoked by racial discrimination, 60 Mexican-American college students who scored above average on the Terrell Racial Discrimination Index were selected and assigned randomly to one of three treatment conditions: systematic desensitization (DS), therapist contact (TC), and no-treatment control (NTC). Before undergoing treatment, subjects completed the Background Information Questionnaire (BIQ), and three measures of negative affect: the Multiple Affect Adjective Check List (MAACL); the Profile of Mood States (POMS); and the Treatment Rating Scales (TRS). After concluding treatment, subjects completed the three measures of negative affect only. Results were nonsignificant with respect to two of the affect measures—the POMS and the MAACL. However, significant differentia1 treatment effects were observed for the TRS measure. Relative to the TC and NTC conditions, subjects in the DS condition evidenced significantly less anger, depression, and anxiety. No other group differences attained the level of statistical significance (p < .05). Several explanations are offered for the negative findings of the MAACL and POMS. These explanations include the possibility that the measures themselves are insensitive to treatment effects. Nevertheless, due to the significant findings of the TRS, it is concluded that systematic desensitization proves effective in alleviating the negative emotional responses of Mexican Americans to racial discrimination. The implications of these findings are discussed.
56

The Efficacy of Anxiety-Relief Therapy and Systematic Desensitization in the Treatment of Snake-Phobic Behavior

Sealy, Thomas Beauchamp 12 1900 (has links)
The purpose of this study is to determine the efficacy of anxiety-relief therapy when compared with three other treatment groups (group systematic desensitization; a pseudo-therapy, suggestion, group; and a no-treatment group).
57

BETA 2 NICOTINIC ACETYLCHOLINE RECEPTOR CONTRIBUTIONS TO ANXIETY-LIKE BEHAVIOR

Anderson, Shawn 21 November 2013 (has links)
Nicotine is a major psychoactive ingredient in tobacco that is thought to promote smoking behavior via nicotinic acetylcholine receptors (nAChRs) in the brain. Given reports that people smoke to relieve anxiety and that anxiety precipitates relapse, the overarching goal of this dissertation research is to assess beta 2 subunit containing nAChR (beta2*nAChR) contributions to anxiety-like behavior. Nicotine’s activity at beta2*nAChRs is concentration-dependent, with high concentrations facilitating activation followed by rapid desensitization and low concentrations preferentially desensitizing beta2*nAChRs; hence, activation or inhibition of beta2*nAChRs may support smoking behavior. Rodent studies reveal that nicotine affects anxiety-like behavior dose-dependently: low doses promote anxiolysis- and high doses support anxiogenic-like behavior. These pharmacological and genetic studies in mice test the hypothesis that nicotine administration promotes anxiolysis via inactivation of beta2*nAChRs and begin to identify which subunits, namely alpha 4 and alpha 6, work in concert with beta 2 to affect anxiety-like behavior. Low dose nicotine and inhibition of beta2*nAChRs supported anxiolysis-like behavior in a number of tasks with predictive validity for anxiolysis efficacy. These studies further suggest that activation of alpha6beta2*nAChRs is sufficient to produce anxiogenic-like behavior and that inhibition of alpha4beta2*nAChRs supports anxiolysis-like behavior. A secondary goal of these studies is to assess if beta2*nAChRs affect anxiety-like behavior during aging. Dysregulation of cholinergic tone can increase anxiety in the elderly, but little is known regarding beta2*nAChR contributions to anxiety in this population or where in the brain this may take place. These studies show that alpha4beta2*nAChR expression differentially affects anxiety-like behavior in adult and aged mice. With a focus on the lateral septum, a GABA-ergic limbic nucleus thought to regulate anxiety-like responses to external stimuli, a third goal of these studies is to elucidate the neuroanatomical and intracellular underpinnings of anxiety-like behavior that are affected by beta2*nAChR inhibition and expression. Previous studies demonstrate that exposure to stressors reduces phosphorylation of extracellular regulated kinase (ERK) in the lateral septum. In these studies, levels of pERK in the lateral septum were inversely associated with alpha4beta2*nAChR expression as well as anxiogenic-like behavior. In sum, these preclinical studies suggest that inhibition alpha4beta2*nAChRs may support cessation in those who smoke to relieve anxiety.
58

Revisão sistemática: imunoterapia específica para venenos de hymenoptera / Systematic review: specific immunotherapy for Hymenoptera venoms

Watanabe, Alexandra Sayuri 14 September 2006 (has links)
A hipersensibilidade a veneno de Hymenoptera representa importante problema do ponto de vista de saúde da população, uma vez que pacientes alérgicos aos componentes do veneno podem desenvolver reações graves, às vezes fatais. A única profilaxia efetiva em pacientes sensibilizados é a imunoterapia veneno específica. Objetivos: avaliar as evidências científicas a respeito dos efeitos da imunoterapia específica utilizada na profilaxia secundária das reações graves em pacientes sensibilizados a veneno de Hymenoptera, por meio da realização de uma revisão sistemática. Métodos: a estratégia de busca seguiu as recomendações do Grupo de Pele da Colaboração Cochrane. A pesquisa foi realizada nas seguintes bases de dados: MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), EMBASE, LILACS, SciSEARCH e nas referências de artigos mais relevantes. Todos os ensaios clínicos controlados e randomizados envolvendo imunoterapia com veneno de Hymenoptera versus imunoterapia com placebo ou apenas seguimento dos pacientes foram avaliados. Dois revisores de forma independente (ASW e LAMF) avaliaram a elegibilidade e a qualidade metodológica de cada ensaio clínico e extraíram os dados. O risco de reações sistêmicas, conseqüentes a ferroada acidental ou a teste de provocação com o inseto responsável, após a imunoterapia específica, foi avaliado por meio do cálculo do odds ratio e do respectivo intervalo de confiança de 95%. Resultados: 2267 resumos foram identificados. A maioria dos artigos foi excluída pelas seguintes razões: os estudos não eram controlados e randomizados ou não satisfaziam alguns critérios de inclusão. Apenas quatro estudos foram analisados. A idade dos pacientes variou entre dois e 65 anos. Apenas um estudo comparou imunoterapia com veneno de formiga contra placebo (Brown et al.) e três estudos (Hunt et al., Schubert et al. e Valentine et al.) comparam imunoterapia com venenos de abelha e vespa contra placebo ou seguimento de pacientes. Em cada estudo, o odds ratio para reações sistêmicas foi: Hunt et al.- Grupo I (veneno) x III (placebo): 0,10 (0,01 <OR < 0,68) Schubert et al.: 0,35 (0,05<OR<2,56); Valentine et al.: 0,16 (0,02 < OR < 1,21) e Brown et al.: 0,04 (0,01<OR<0,28). Após o teste de heterogeneidade, apenas dois estudos (Schuberth 1983 e Valentine 1990) se mostraram homogêneos o suficiente e assim puderam ser incluídos na meta-análise (p = 0,623). Ao combinar os dois estudos, o odds ratio passou a ser significativo: 0.29 (0.10 a 0.87). Entretanto, ao analisar a gravidade das reações ocorridas após a imunoterapia, observou-se que os benefícios podem não ser tão relevantes, pois as reações foram, na grande maioria, ou mais leves ou semelhantes à reação original. Conclusões: A imunoterapia específica deve ser recomendada para adultos que apresentaram reações sistêmicas e para crianças com reações moderadas a graves, porém não é necessária em crianças que apresentaram apenas reações cutâneas após ferroada de abelha ou vespa, principalmente se a exposição for esporádica. / Background: Hymenoptera venom hypersensitivity is a significant public health problem. For patients who are allergic to components of the venom, reactions can be severe and sometimes fatal. The only effective treatment in the management of those patients is the specific venom immunotherapy. Objective: to assess the effects of the specific venom immunotherapy for Hymenoptera venom hypersensitivity through a systematic review. Methods: the standard search strategy of the Cochrane Skin Group was used for searches of electronic and other databases. These included MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), EMBASE, LILACS, SciSEARCH and the references of relevant articles. All randomized controlled trials involving Hymenoptera venom immunotherapy versus immunotherapy with placebo or only follow-up of the patients were included. Two independent reviewers (ASW and LAMF) assessed the eligibility, and the methodological quality of each trial, and extracted the data. Post immunotherapy risk of systemic reactions after either challenge or accidental stings was calculated through the odds ratio and respective 95 percent confidence interval. Main results: 2,267 abstracts, identified through electronic sources, were assessed. Most articles were excluded for the following reasons: the studies did not satisfy all the inclusion criteria or they were not randomized controlled trials. Four studies were included on this review. The age of the participants varied between two and 65 years. Only one study compared ant venom immunotherapy with placebo (Brown et al.) and three studies (Hunt et al., Schubert et al. and Valentine et al.) compared bees and wasps immunotherapy with placebo or simply patient follow-up. In each study, the odds ratio to a systemic reaction was: Hunt et al.- Group I (venom) x III(placebo): 0,10 (0,01 < OR < 0,68) Schubert et al.: 0,35 (0,05 < OR < 2,56); Valentine et al.: 0,16 (0,02 < OR < 1,21) and Brown et al.: 0,04 (0,01 < OR < 0,28). After the heterogeneity test (p = 0,623), only two studies (Schuberth 1983 and Valentine 1990) were homogeneous enough as to be included in a meta-analysis. The summary odds ratio was 0.29 (IC 95%: 0.10 - 0.87). However, when the severity of the reaction occurring after the sting challenge or accidental sting was taken into account, the benefits were not so relevant because the reactions were, for the most, milder than the original one. Conclusions: The specific-venom immunotherapy must be recommended for adults with systemic reactions and for children with moderate to severe reactions, but there is no need to prescribe it for children who present only skin reactions after insects sting, particularly if the exposure is sporadic.
59

Mediadores e mecanismos envolvidos no processo de sensibilização e dessensibilização a picadas do mosquito Aedes aegypti. / Mediators and mechanisms involved in the sensitization and desensitization to Aedes aegypti bites.

Santos Neto, Leila 04 May 2018 (has links)
Fêmeas da espécie Aedes aegypti são vetores de importantes doenças como dengue, febre amarela, Chikungunya e Zika. A alimentação sanguínea realizada pelo mosquito fêmea é importante e necessária para a maturação dos ovos. Durante este processo, os mosquitos hematófagos precisam lidar com desafios impostos pelo hospedeiro vertebrado como a barreira da hemostasia e seu sistema imunológico. Estudos clássicos mostraram que a exposição à saliva do mosquito é capaz de sensibilizar o homem, embora boa parte dos indivíduos apresente dessensibilização às proteínas salivares ao longo da vida. Resultados recentes do nosso grupo sugerem que o processo de sensibilização e dessensibilização pode ser reproduzido em modelo murino. Diante do exposto, o presente trabalho teve como objetivo estudar os processos de sensibilização e dessensibilização aos antígenos salivares de A. aegypti, seu impacto no fitness biológico do mosquito (ingestão de sangue, oviposição e escolha do hospedeiro) e potenciais moléculas envolvidas nesse processo. Inicialmente, padronizamos um modelo de exposição natural, no qual camundongos BALB/c fêmeas foram expostos 10 vezes às picadas de 30 mosquitos A. aegyptifêmeas, com um intervalo de 15 dias entre cada exposição. Avaliamos o perfil de anticorpos séricos entre cada exposição e observamos uma mudança no padrão de anticorpos ao longo do tempo, inicialmente com forte componente Th2 (IgE total e IgG1 específica) e mais tardiamente, a presença de um componente Th1 (IgG2a específica). Além disso, o soro de animais expostos 4 vezes aos mosquitos apresentou atividade anafilática dependente de IgE superior ao soro de animais naive e de animais expostos 10 vezes ao mosquito. O perfil de citocinas presentes em culturas de células totais de baço mostrou forte produção de IL-4 e IL-5 antígeno-específicas, que foi semelhante entre os grupos expostos 4 ou 10 vezes aos mosquitos. A avaliação da migração celular na orelha induzida pelas picadas do mosquito mostrou que, comparado com as células residentes da orelha de animais naive, todos os tipos celulares fenotipados estavam presentes maior quantidade em tanto em animais expostos 4 vezes quanto expostos 10 vezes aos mosquitos, com destaque para os eosinófilos (aumentados ~2000 e ~1000 vezes, respectivamente). Entretanto, o número total de eosinófilos e de linfócitos B se mostrou reduzido, enquanto o número de neutrófilos estava aumentado, nos animais expostos 10 vezes quando comparados aos animais expostos 4 vezes. Do ponto de vista do vetor, não observamos grandes alterações no volume de sangue ingerido durante o repasto sanguíneo, embora haja uma tendência de maior aquisição de sangue em animais expostos 7 vezes ao mosquito. Por outro lado, a oviposição foi gradativamente diminuída entre a segunda e a sétima exposição quando comparada com a primeira exposição, voltando aos níveis originais à partir da oitava exposição. Um modelo de inflamação peritoneal aguda induzido pela inoculação do extrato da glândula salivar (EGS) de fêmeas do mosquito A. aegypti, revelou um aumento de eosinófilos, semelhante ao observado no modelo crônico de inflamação na orelha. Esse modelo foi usado para estudar o papel de moléculas do hospedeiro potencialmente envolvidas na migração eosinofílica em resposta aos antígenos salivares, revelando a importância da IL-5 e dos leucotrienos nesse processo. Assim, podemos concluir que a saliva do mosquito A. aegypti provoca uma forte resposta alérgica em camundongos, que apesar de não alterar o volume de sangue ingerido pelos mosquitos, é capaz de afetar sua oviposição. A exposição crônica induz um processo de dessensibilização, com aumento de anticorpos de perfil Th1 e diminuição da migração de eosinófilos no sítio da picada, mas que se refletiu em maior oviposição por parte dos mosquitos. Finalmente, IL-5 e leucotrienos são mediadores que parecem estar envolvidos na inflamação eosinofílica em resposta aos componentes salivares do mosquito. / Females of Aedes aegypti species are vectors of important diseases such as dengue, Yellow Fever, Chikungunya Fever and Zika. The blood meal is essential and necessary for the maturation of eggs in female mosquitoes. During this process, hematophagous mosquitoes need to cope with challenges imposed by the vertebrate host, such as the hemostasis and the immune system barriers. Classical studies have shown that exposure to mosquito saliva is able to sensitize humans, although most individuals show desensitization to salivary proteins throughout their lives. Recent results from our group suggest that the process of sensitization and desensitization can be reproduced in a murine model. Thus, the aim of the present work was to study the sensitization and desensitization processes to A. aegypti salivary antigens, their impact on the biological fitness of the mosquito (blood ingestion, oviposition and host choice) and potential molecules involved in this process. Initially, we standardized a model of natural exposure in which female BALB/c mice were exposed 10 times to the bites of 30 female A. aegypti mosquitoes, with a 15-day interval between each exposure. We evaluated the serum antibody profile between each exposure and observed a change in antibody pattern over time, initially with a strong Th2 component (total IgE and specific IgG1) and later, the presence of a Th1 (specific IgG2a) component. In addition, the serum of animals exposed 4 times to the mosquitoes showed stronger IgE-dependent anaphylactic activity than the serum of naive animals and animals exposed 10 times to the mosquitoes. The cytokine profile in spleen cell cultures showed strong antigen-specific production of IL-4 and IL-5, similar between the groups exposed 4 or 10 times to the mosquitoes. The evaluation of cell migration into the ear induced by mosquito bites showed that, compared to the resident cells of the ear of naive animals, all phenotyped cell types were present in larger amounts in both animals exposed, 4 times and 10 times, to mosquitoes, specially eosinophils (increased ~2000 and ~1000 times, respectively). However, the total number of eosinophils and B lymphocytes was reduced, while the number of neutrophils was increased, in animals exposed 10 times when compared to animals exposed 4 times. From the vector perspective, we did not observe significant changes in the volume of blood taken during the blood feeding, although there is a tendency of greater blood acquisition in animals exposed 7 times to the mosquitoes. On the other hand, the oviposition was gradually diminished between the second and the seventh exposure when compared to the first exposure, returning to the original levels from the eighth exposure. A model of acute peritoneal inflammation induced by the inoculation of female A. aegypti salivary gland extract (SGE) revealed an increase in eosinophils, similar to that observed in the chronic model of inflammation in the ear. This model was used to study the role of host molecules potentially involved in eosinophil migration in response to salivary antigens, revealing the importance of IL-5 and leukotrienes in this process. Thus, we can conclude that the saliva of the A. aegypti mosquito causes a strong allergic response in mice that it does not alter the volume of blood ingested by mosquitoes, but it is able to affect their oviposition. Chronic exposure induced a desensitization process, with increased antibodies of Th1 profile and decreased eosinophil migration to the bite site, but that resulted in greater oviposition by the mosquitoes. Finally, IL-5 and leukotrienes are mediators that seem to be involved in eosinophilic inflammation in response to the salivary components of the mosquito.
60

Etude mécanistique des récepteurs P2X par l'utilisation de molécules photoisomérisables / Mechanistic study of P2X receptors by photoisomerisable molecules

Beudez, Juline 09 November 2018 (has links)
Les récepteurs P2X, activés par l’ATP extracellulaire et cations non-sélectifs, sont impliqués dans de nombreux rôles physiopathologiques. Le manque de sélectivité de molécules pharmacologiques est un inconvénient majeur pour leur étude. La résolution de leurs structures cristallographiques a permis de les comprendre à l’échelle moléculaire, cependant les mécanismes impliqués dans les transitions allostériques restent mal compris. Au laboratoire, deux outils, dérivés d’azobenzène, permettant l’activation des récepteurs P2X en absence d’ATP et par la lumière ont été développés. L’utilisation de ces outils ont permis l’étude de la transition allostérique de l’état ouvert à l’état désensibilisé, mettant en avant une zone de régulation efficace dans les espaces transmembranaires. De plus, leur utilisation a permis l’investigation biophysique d’une mutation présente sur P2X2 humain, responsable d’une surdité non-syndromatique. Cette mutation entraine un rétrécissement du pore, impactant le passage de gros cations impliqués dans le processus d’audition. Enfin, la relation entre le diamètre du pore ionique et le passage de gros cations a été établi. / P2X receptors, activated by extracellular ATP and non-selective cations, are involved in many physiopathological roles. The lack of selectivity of pharmacological molecules is a major drawback for their study. The resolution of their crystallographic structures provided a molecular framework, but the mechanisms involved in allosteric transitions remain misunderstood. In the laboratory, two tools have been developed, derived from azobenzene, allowing the activation of P2X receptors in the absence of ATP and by light. The use of these tools allowed the study of the allosteric transition from the open to the desensitized state, highlighting an effective regulatory zone in transmembrane spaces. In addition, their use provided the biophysical investigation of a mutation present on hP2X2, responsible for non-syndromatic hearing loss. This mutation leads to a narrowing of the pore, affecting the large cations flow involved in hearing process. Finally, the relationship between the diameter of the ionic pore and the passage of large cations has been established.

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