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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

Participação dos receptores de potencial transitório no efeito antinociceptivo orofacial da frutalina

Damasceno, Marina de Barros Mamede Vidal 30 June 2016 (has links)
Made available in DSpace on 2019-03-30T00:12:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-06-30 / Orofacial pain of multiple causes is a highly prevalent clinical condition. It has been suggsted transient receptor potential (TRP) channels play a role in the peripheral mechanisms. Much attention is currently focused on the anti-inflammatory and antinociceptive properties of lectins. This is the first study that evaluate the ability of a lectin to attenuate orofacial pain in experimental animal models. The purpose of this study was to evaluate the antinociceptive effects of frutalin (FTL), an ¿-D-galactosebinding lectin isolated from the seeds of Artocarpus incisa L. Using rodent models of acute orofacial, neuropathic and corneal nociception. Acute pain was induced by administration of formalin, glutamate or capsaicin s.c. in the perinasal area or by instillation of hypertonic saline in the cornea of mice pretreated with FTL (0.25; 0.5 or 1 mg/kg i.p.). Some of the animals in the corneal nociception model were pretreated with L-NAME or naloxone in order to identify the antinociceptive mechanism of FTL. Also, lectin-sugar (D-galactose) binding was allowed to determine the involvement of sugar residues in the lectin effect. A FTL 0,5 mg/kg was the most effective, therefore the dose being chosen to be used in this model. Furthermore, formalin was injected into the temporomandibular joint of rats pretreated with FTL (0.5 mg/kg, i.p.). Nociceptive response was proxied by intensity of rubbing and head flinching. Neuropathic nociception was induced by transection of the infraorbital nerve (IONX), followed by acetone-induced cold hypersensitivity in rats pretreated with FTL (0.5 mg/kg, i.p.). The effect of FTL on motor activity in mice was evaluated with the rotarod test. FTL was found to significantly reduce orofacial nociceptive behaviors induced by formalin (in both stages of the test), glutamate and capsaicin. In the corneal nociception test, rubbing was less intense in animals pretreated with FTL. The effect was reverted by L-NAME and D-galactose, but not by naloxone. FTL reduced rubbing but not head flinching in animals injected with formalin. In animals submitted to IONX, FTL significantly reduced facial rubbing (decreased thermal hypersensitivity) on postoperative days 3, 5, 7 and 10, compared to controls (sham and naïve). No motor changes were observed in the rotarod test. Our findings suggest that FTL may act by blocking TRP channels since it reduced nociception induced by capsaicin, glutamate and saline (TRPV1 channel), formalin (TRPA1 and TRPV4 channels) and acetone (TRPM8 and TRPA1 channels). The effect of FTL was associated with its lectin domain. Thus, the study confirmed the ability of FTL to pharmacologically inhibit orofacial nociception in acute and chronic pain. Key words: Lectins; Frutalin; Artocarpus incisa L; Orofacial Nociception; Neuropathic Pain. / A dor orofacial é uma condição clínica altamente prevalente, que possui múltiplas causas. Têm sido sugerido que os canais da família dos TRP (receptor de potencial transitório) devem estar envolvidos nos mecanismos periféricos desta condição. Atualmente, as propriedades anti-inflamatórias e antinociceptivas das lectinas têm sido amplamente estudadas. Este é o primeiro estudo que avalia a capacidade de uma lectina de atenuar a dor orofacial em modelos experimentais animais. Tendo portanto como objetivo avaliar a atividade antinociceptiva da frutalina (FTL), lectina ¿-D galactose ligante, que é isolada das sementes de Artocarpus incisa L., utilizando modelos de nocicepção orofacial aguda e neuropática e corneal em roedores. A nocicepção aguda foi induzida pela administração subcutânea (s.c.) de formalina, glutamato ou capsaicina na área perinasal de camundongos ou pela instilação de salina hipertônica na córnea de camundongos pré-tratados com FTL (0,25; 0,5 ou 1 mg/kg i.p.). Em seguida foi avaliado o comportamento de rubbing da região afetada. Ainda utilizando o modelo de nocicepção corneal foi avaliado o efeito do pré-tratamento com L-NAME ou Naloxona, na tentativa de elucidarmos o possível mecanismo de ação da FTL. Foi deterrminado também neste mesmo modelo, o envolvimento do domínio lectínico no efeito antinociceptivo dessa lectina, através da ligação dela com o seu açúcar (D-galactose). A FTL 0,5 mg/kg foi a mais efetiva, sendo portanto a dose escolhida para ser utilizada neste modelo. A formalina também foi aplicada na articulação temporomandibular (ATM) de ratos pré-tratados com FTL 0,5 mg/kg (i.p.). A resposta nociceptiva foi caracterizada pelos comportamentos de rubbing e head flinching. A nocicepção neuropática foi induzida pela transecção do nervo infraorbital (IONX), seguida de hipersensibiliadade ao frio induzida por acetona, em ratos pré-tratados com FTL 0,5 mg/kg (i.p.). Para avaliar a interferência da FTL no comportamento locomotor dos animais foi realizado o teste Rota-rod em camundongos. Nossos resultados mostraram que a FTL reduziu significativamente o comportamento nociceptivo orofacial induzido pela formalina (em ambas as fases do teste), glutamato e capsaicina. No teste de nocicepção corneal, os animais pré-tratados com FTL apresentaram diminuição significativa do comportamento de rubbing ocular. Este efeito foi revertido por L-NAME e Dgalactose, mas não por Naloxona. A FTL reduziu o comportamento de rubbing, mas não de head flinching dos animais que receberam formalina na ATM. Na hipersensibilidade ao frio induzida pela acetona, após a transecção do nervo infraorbital, os ratos tratados com FTL tiveram uma diminuição significativa do comportamento de rubbing facial (menor hipersensibilidade térmica) nos dias 3, 5, 7 e 10, após o procedimento cirúrgico, quando comparado aos grupos controles (sham e naive). Os animais submetidos ao teste Rota-rod não apresentaram incordenação motora. Os resultados sugerem que a FTL pode estar atuando via bloqueio dos canais TRPs, uma vez que reduziu o efeito nociceptivo induzido pela capsaicina, glutamato e salina hipertônica, (que atuam no canal TRPV1), pela formalina (que atua nos canais TRPA1e TRPV4) e pela acetona (que atua nos canais TRPM8 e TRPA1). Esse efeito está associado ao seu domínio lectínico. Com base nesses achados, podemos confirmar o potencial farmacológico da FTL como um inibidor da nocicepção orofacial na dor aguda e crônica. Palavras-chaves: Lectinas; Frutalina; Artocarpus incisa L; Nocicepção orofacial; Dor Neuropática.
52

CaracterizaÃÃo fÃsico-quÃmica e avaliaÃÃo in vitro de diferentes formulaÃÃes da soluÃÃo de Carnoy sobre substratos Ãsseo e dentÃrio humanos / Physical-chemical characterization and in vitro evaluation of different formulations of the Carnoyâs solution on human bone and dental substrates.

Francisco Samuel Rodrigues Carvalho 06 February 2017 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A regiÃo maxilofacial pode ser afetada por uma variedade de lesÃes benignas (odontogÃnicas e nÃo-odontogÃnicas), mas localmente invasivas. O emprego de um tratamento conservador pode gerar altas taxas de recorrÃncia, enquanto que uma abordagem radical pode acarretar desordens estÃtico-funcionais. O uso da soluÃÃo de Carnoy, enquanto terapia complementar ao tratamento cirÃrgico, tem sido descrito na literatura com o propÃsito de reduzir as taxas de recorrÃncias dessas lesÃes, alÃm de minimizar danos decorrentes de um tratamento cirÃrgico agressivo. Dessa forma, a presente dissertaÃÃo à constituÃda por dois capÃtulos que tÃm como objetivo, respectivamente: 1) caracterizar as propriedades fÃsico-quÃmicas e farmacolÃgicas da soluÃÃo de Carnoy com e sem clorofÃrmio; 2) avaliar in vitro o efeito de diferentes formulaÃÃes da soluÃÃo de Carnoy sobre substratos humanos calcificados. Como abordagens metodolÃgicas, foram realizados estudos laboratoriais. No CapÃtulo 1, procedeu-se com a avaliaÃÃo das propriedades fÃsico-quÃmicas/farmacolÃgicas e comportamento de diferentes formulaÃÃes da soluÃÃo de Carnoy utilizada em cirurgia oral e maxilo-facial atravÃs de microespectroscopia Raman, espectrofotometria UV/VisÃvel, entre outras. Os resultados, desse estudo, evidenciaram que a soluÃÃo de Carnoy apresenta pH Ãcido e, quando da presenÃa do clorofÃrmio, esta torna-se levemente mais Ãcida, bem como confere à soluÃÃo maior viscosidade. Quando as soluÃÃes nÃo foram filtradas apÃs sua preparaÃÃo ocorreu precipitaÃÃo de sais de ferro apÃs o sÃtimo dia quando da utilizaÃÃo do clorofÃrmio em sua composiÃÃo. No CapÃtulo 2, foi realizado um estudo com 36 terceiros molares inferiores e 18 fragmentos Ãsseos mandibulares, ambos doados e coletados de humanos, os quais foram divididos em trÃs grupos: dois grupos experimentais (Grupo I = soluÃÃo de Carnoy com clorofÃrmio; Grupo II = soluÃÃo de Carnoy sem clorofÃrmio) e um grupo controle (soluÃÃo salina). As amostras foram avaliadas atravÃs de microespectroscopia Raman, teste de microdureza Knoop e microscopia eletrÃnica de varredura (MEV) com anÃlise do espectro de energia dispersiva de raios X (EDX). Houve desmineralizaÃÃo/degradaÃÃo das estruturas dentÃrias tanto nas relaÃÃes matriz mineral/matriz orgÃnica e carbonato/fosfato (GI e GII; p<0,05), quanto na relaÃÃo entre os subtipos de colÃgeno (GII; p<0,05). No tecido Ãsseo foi observada degradaÃÃo pela reduÃÃo na relaÃÃo entre os subtipos de colÃgeno (GI e GII; p<0,05). A presenÃa do clorofÃrmio resultou em uma reduÃÃo estatisticamente significante na microdureza superficial das amostras de tecidos dentÃrios (p=0,036). Nos grupos experimentais, o MEV/EDX evidenciou significativas alteraÃÃes estruturais em todas as amostras analisadas. Como conclusÃes de ambos os estudos, tem-se que: (1) a soluÃÃo de Carnoy à uma soluÃÃo estÃvel quando armazenada em temperatura ambiente que, na presenÃa de clorofÃrmio, à passÃvel de precipitaÃÃo de sais de ferro, sofre aumento de sua viscosidade, e seu pH torna-se levemente mais Ãcido; (2) ambas as formulaÃÃes da soluÃÃo de Carnoy (com ou sem clorofÃrmio) apresentam capacidade de desmineralizaÃÃo quando aplicada sobre tecidos humanos calcificados, promovendo alteraÃÃo tanto na matriz mineral quanto na matriz orgÃnica; (3) a presenÃa do clorofÃrmio na soluÃÃo de Carnoy propicia um maior potencial de desmineralizaÃÃo e penetrabilidade teciduais.
53

Aetiology and mechanism of injury of midfacial fractures: a prospective study of the Johannesburg region

Suleman, Yusuf Farouk 14 October 2009 (has links)
M.Dent., Faculty of Health Sciences, University of the Witwatersrand, 2008. / Objective: To determine the aetiology, biomechanics and demographics of patients with fractures of the midface. Materials and Methods: Patients with midface fractures (who consented to participate in the study) who presented to the Division of Maxillofacial and Oral Surgery over a 12 month period from December 2005 to December 2006 were included in the study. Data was recorded on age, race, gender, date and cause of injury, associated injuries and use of alcohol at the time of injury. The fractures were grouped into Le Fort, zygomatico‐maxillary, dentoalveolar and panfacial fractures. Results: The sample comprised 94 patients; 78 (82.98%) males and 16 (17.02%) females with an age range of 3 to 67 years. Blacks accounted for 77.66% of the total sample, followed by Whites (12.77%), Coloureds (6.38%) and Asians (3.19%). Blunt trauma due to interpersonal violence, motor vehicle accidents, gun shot wounds and falls contributed to 40.5%, 26.6%, 13.8% and 5.3% of the fractures respectively. Le Fort fractures were less commonly observed than zygomaticomaxillary complex midface fractures. Conclusion: A relationship exists between facial trauma, poverty and alcohol consumption. Blunt trauma due to interpersonal violence is the most common cause of midface injuries. Majority of injuries are sustained during weekends. Zygomaticomaxillary complex fractures are the most common midface fractures.
54

Perceptions of Plastic Surgeons, Orthodontists, and Laypersons to Altered Facial Balance

Marcy, Sean 12 January 2011 (has links)
Objective: To quantify the acceptability of facial asymmetry to plastic surgeons, orthodontists and the lay population. Methods: Facial images were animated with one of six asymmetries: jaw and nasal deviation, interocular distance, ocular height, angulation, and shape. Evaluators were asked to judge the faces based on their visual acceptability. Results: There were no differences between the groups except for in the evaluation of ocular shape. Mandibular deviation of 4mm, and nasal deviation of 3mm was judged as unacceptable. 9% rounder and 18% flatter eyes were considered unacceptable. Hypertelorism and inferior ocular dystopia was unacceptable after a change of 2mm. Hypotelorism and superior vertical dystopia was unacceptable after a change of 2.5mm. Ocular angulations of 5.5 degrees superiorly and 3.5 degrees inferiorly were unacceptable. Conclusions: Plastic surgeons, orthodontists, and lay people find specific facial asymmetries to be unacceptable at similar levels of deviation.
55

Perceptions of Plastic Surgeons, Orthodontists, and Laypersons to Altered Facial Balance

Marcy, Sean 12 January 2011 (has links)
Objective: To quantify the acceptability of facial asymmetry to plastic surgeons, orthodontists and the lay population. Methods: Facial images were animated with one of six asymmetries: jaw and nasal deviation, interocular distance, ocular height, angulation, and shape. Evaluators were asked to judge the faces based on their visual acceptability. Results: There were no differences between the groups except for in the evaluation of ocular shape. Mandibular deviation of 4mm, and nasal deviation of 3mm was judged as unacceptable. 9% rounder and 18% flatter eyes were considered unacceptable. Hypertelorism and inferior ocular dystopia was unacceptable after a change of 2mm. Hypotelorism and superior vertical dystopia was unacceptable after a change of 2.5mm. Ocular angulations of 5.5 degrees superiorly and 3.5 degrees inferiorly were unacceptable. Conclusions: Plastic surgeons, orthodontists, and lay people find specific facial asymmetries to be unacceptable at similar levels of deviation.
56

The Role of Differential Experience in Facial Age Processing

Anzures, Gizelle 05 January 2012 (has links)
The present study investigated the role of differential experience in one’s processing of facial age information. Study 1 examined how differential experience with own- and other-race individuals, as well as differential experience with own- and other-age individuals, influences children’s and adults’ abilities to process facial age information. Study 2 examined how differential sociocultural experiences influence adults’ abilities to process facial age information. The results suggest that the influence of differential experience with own- and other-race faces is most evident when individuals have extremely limited to no experience with other-race faces. There was also a clear other-age effect in young adults’ facial age judgments, presumably due to their extensive experience with own-age peers. However 9- to 10-year-olds and 13- to 14-year-olds also showed an advantage in processing facial age information for young adult faces relative to child and middle-age adult faces. Thus, the 9- to 10-year-olds and 13- to 14-year-olds may have also had the most extensive experience with young adult individuals relative to individuals from other age groups. In addition, results suggest that the efficiency with which individuals process facial age information is influenced by differential sociocultural emphases on the need to differentiate between the facial ages of social partners.
57

The Role of Differential Experience in Facial Age Processing

Anzures, Gizelle 05 January 2012 (has links)
The present study investigated the role of differential experience in one’s processing of facial age information. Study 1 examined how differential experience with own- and other-race individuals, as well as differential experience with own- and other-age individuals, influences children’s and adults’ abilities to process facial age information. Study 2 examined how differential sociocultural experiences influence adults’ abilities to process facial age information. The results suggest that the influence of differential experience with own- and other-race faces is most evident when individuals have extremely limited to no experience with other-race faces. There was also a clear other-age effect in young adults’ facial age judgments, presumably due to their extensive experience with own-age peers. However 9- to 10-year-olds and 13- to 14-year-olds also showed an advantage in processing facial age information for young adult faces relative to child and middle-age adult faces. Thus, the 9- to 10-year-olds and 13- to 14-year-olds may have also had the most extensive experience with young adult individuals relative to individuals from other age groups. In addition, results suggest that the efficiency with which individuals process facial age information is influenced by differential sociocultural emphases on the need to differentiate between the facial ages of social partners.
58

Human Facial Animation Based on Real Image Sequence

Chang, Ying-Liang 19 May 2003 (has links)
none
59

Análisis de la sonrisa y patrón facial en estudiantes de la Universidad Nacional Mayor de San Marcos

Fernández Vivas, Sandra Paola January 2008 (has links)
La sonrisa tiene una función primordial en las interacciones sociales, culturales y psicológicas; las características de ésta son uno de los principales motivos de consulta odontológica. El cuerpo humano es un conjunto de proporciones donde cada parte del cuerpo guarda relación entre sí para dar armonía por lo que es importante conocer las características de la sonrisa de cada patrón facial ya que estos factores se deben considerar al momento de restaurar el sector anterior. El propósito de este estudio fue describir las características de la sonrisa de cada patrón facial en un grupo de estudiantes entre los 15 y 30 años de edad de ambos géneros. Se tomo una muestra de 216 personas (95mujeres y 121 varones) que fueron clasificados en 5 grupos faciales: hipereuriprosopo, euriprosopo, mesoprosopo, leptoprosopo e hiperleptoprosopo. Se midió clínicamente la altura y ancho facial utilizando un vernier, se tomaron fotografías de las sonrisas y fueron evaluadas por medio de la percepción visual. Se observó que en el patrón facial hipereuriprosopo predominó el tipo de sonrisa media, arco de sonrisa paralelo, la exposición de diez piezas dentales al sonreír y la presencia de correderas bucales. En el patrón facial euriprosopo predominó el tipo de sonrisa alta, el arco de sonrisa paralelo, la exposición de diez piezas dentales al sonreír y la presencia de correderas bucales. En los del tipo mesoprosopo predominó el tipo de sonrisa media, el arco de sonrisa paralelo, la exposición de diez piezas dentales al sonreír y la ausencia de correderas bucales.
60

An empirical and theoretical investigation into the psychological effects of wearing a mask

Cooper, Michael Barry January 1999 (has links)
A review of the literature shows that the wearing of a mask has been hypothesised to bring about four main psychological effects: disinhibition, transformation, facilitation of the expression of aspects of the wearer's Self, and various psycho-somatic changes. Several different explanations have been proposed as to why each of these effects come about. Using theoretical and empirical research, the thesis explores in detail the hypothesis that a mask can disinhibit its wearer, and that this disinhibition comes about because the mask-wearer feels less identifiable. The findings show that a mask can significantly reduces its wearer's feelings of identifiability, and that it can also significantly reduce its wearer's public selfawareness as a consequence of changes in attentional focus. However, the empirical evidence suggests that the mask's disinhibiting effect is limited to situations in which an individual wants to behave in a particular way, but inhibits that behaviour out of a concern with 'maskable' facets of their public self. Concomitantly, the findings suggest that, if an individual wants to behave in a way for which they require 'mask-able' facets of the public self, then the wearing of a mask may be experienced as inhibiting. This thesis also examines the hypothesis that a mask can transform its wearer, and that this occurs through the self-attribution process outlined by Kellerman and Laird (1982). The thesis provides strong empirical support for both these hypotheses, showing that the wearing of a mask can make individuals feel less like their usual self and more like the character represented in the mask. However, the empirical evidence suggests that this latter effect only occurs under conditions in which an individual is specifically focused on their masked appearance. A final chapter discusses the theoretical and applied implications of these findings, with specific reference to the use of masks in therapeutic practice.

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