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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.
141

Córtex cingulado anterior e respostas nociceptivas em cobaias: modulação GABAérgica, colinérgica e opioidérgica / Anterior cingulate cortex and nociceptive responses in a subject: gabaergic modulation, cholinergic and opioidergic

João Zugaib Cavalcanti 23 February 2012 (has links)
A dor é um fenômeno multidimensional, que geralmente desencadeia reações emocionais desconfortáveis quando identificada. Sua relação com injúria tecidual pode ser interpretado como um mecanismo adaptativo de defesa à integridade do organismo, tendo em vista sua preservação evolutiva. Porém, o substrato neurobiológico do organismo parece determinar a complexificação do repertório comportamental em diferentes espécies. Nesse sentido, o córtex cingulado anterior (CCA) tem sido amplamente descrito em mamíferos modulando diferentes aspectos da dor. O presente trabalho utilizou os testes algesimétricos de vocalização e da formalina em cobaias, para se avaliar o decurso temporal do efeito da microinjeção de agonistas e antagonistas GABAérgico (muscimol e bicuculina); colinérgico (carbacol e atropina) e opioidérgico (morfina e naloxona). A microinjeção de bicuculina (1 nmol / 0,2 µl) exacerbou as respostas nociceptivas em ambos os testes, porém diferentes doses de muscimol (0,5, 1 e 2 nmol / 0,2 µl), não modificaram as respostas. O efeito da bicuculina foi bloqueado em ambos os testes pela microinjeção prévia de muscimol (1 nmol/ 0,2 µl) no CCA. A microinjeção de carbacol (2,7 nmol /0,2 µl) neste substrato promoveu antinocicepção, evidenciada por meio da atenuação da amplitude das vocalizações, mas não pelo teste da formalina. Esse efeito foi bloqueado pela administração prévia de atropina (0,7 nmol /0,2 µl) e de naloxona (2,7 nmol /0,2 µl). A microinjeção de morfina (4,4 nmol /0,2 µl) promoveu antinocicepção em ambos os testes. Concluímos que a inibição do tônus GABAérgico no CCA exacerba os comportamentos nociceptivos e que a antinocicepção promovida por carbacol pode ter sido mediada pelo sistema de opióides endógenos, tendo em 9 vista o bloqueio do seu efeito com naloxona. Além disso, a estimulação opióide promove uma contundente antinocicepção. / Pain is a multidimensional phenomenon which usually triggers uncomfortable emotional reactions when identified. Its relation injury can be interpreted as an adaptive mechanism to defend the integrity of the body given its evolutionary conservation. However the neurobiological substrate of the body seems to determine the complexification of behavioral repertoire in different species. Thus, the anterior cingulated cortex (ACC) has been widely described in mammals by modulating different cognitive aspects of pain. This study used algesimetric tests of vocalization and formalin in guinea pigs to evaluate the time course of the effect of microinjection of GABA agonists and antagonists (bicuculline and muscimol) and cholinergic (carbachol and atropine) beyond the opioid antagonist naloxone. The microinjection of bicuculline (1 nmol / 0,2 µl) exacerbated the nociceptive behavior in both tests but different doses of muscimol (0,5; 1 e 2 nmol / 0,2 µl) did not change the responses. The effect of bicuculline was blocked in both tests by prior microinjection of muscimol (1 nmol / 0,2 µl) in the ACC. The microinjection of carbachol (2,7 nmol / 0,2 µl) on this substrate promoted antinociception as evidenced by attenuation of the amplitude of the vocalizations, but not by the formalin test. This effect was blocked by prior administration of atropine (0,7 / 0,2 µl) and naloxone (0,7 nmol / 0, 2 µl). The microinjection of morphine (4,4 nmol / 0,2 µl) promoted antinociception in both tests. We conclude that inhibition of GABAergic tone in the ACC exacerbates nociceptive behaviors and that the antinociception promoted by carbachol may 11 have been mediated by endogenous opioid system in order blocking its effect with naloxone. In addition opioid stimulation promotes a striking antinociception.
142

Caracterização das fases imediata e tardia da resposta inflamatória de tecido pulmonar periférico de cobaias sensibilizadas / Comparison of early and late responses to antigen of sensitized guinea pigs parenchymal lung strips

Tatiana Lanças 21 September 2006 (has links)
O parênquima pulmonar periférico tem sido estudado como um componente da resposta inflamatória na asma. Durante uma constrição induzida, a resistência do tecido aumenta em diferentes modelos de asma. Aproximadamente 60% dos pacientes asmáticos possuem respostas imediata e tardia. A resposta tardia é caracterizada por obstrução mais grave de vias aéreas. No presente estudo, foi avaliada a mecânica de fatias de parênquima pulmonar em cobaias sensibilizadas com ovoalbumina (OVA), tentando reproduzir ambas as repostas imediata e tardia. A mecânica oscilatória de fatias pulmonares foi realizada em um grupo controle (C), em um grupo de resposta imediata (IM) e em dois grupos de resposta tardia: 17 (T1) e 72 (T2) horas após o último desafio com ovoalbumina. Medidas de resistência (R) e elastância (E) foram obtidas antes e depois do desafio com OVA nos grupos C e IM e antes e depois do desafio com Acetilcolina (ACh) em todos os grupos. Com o uso de morfometria, foram avaliadas as densidades de eosinófilos e de células musculares lisas, assim como o conteúdo de colágeno e elastina nas fatias pulmonares. Os valores de R e E basais e pós-agonista estão aumentados nos grupos IM, T1 e T2 quando comparados com o grupo C (p = 0.001). A análise morfométrica mostrou um aumento na densidade de eosinófilos nas fatias de tecido periférico dos grupos IM e T2 quando comparados com o grupo C (p < 0.05). Houve uma correlação positiva significante entre a densidade de eosinófilos nas fatias de parênquima dos grupos C, T1 e T2 e os valores de R e E pós-ACh (r = 0,71, p = 0.001 e r = 0,74, p < 0.001, respectivamente). Os resultados mostram que o parênquima pulmonar está envolvido na resposta tardia deste modelo de inflamação alérgica crônica e que a resposta constritora nesta fase está relacionada à inflamação eosinofílica. / The peripheral lung parenchyma has been studied as a component of the asthmatic inflammatory response. During induced constriction, tissue resistance increases in different asthma models. Approximately 60% of the asthmatic patients show early and late responses. The late response is characterized by more severe airway obstruction. In the present study, we evaluated lung parenchymal strips mechanics in ovalbumin-sensitized guinea pigs, trying to reproduce both early and late inflammatory responses. Oscillatory mechanics of lung strips were performed in a control group (C), in an early response group (ER), and in two late response groups: 17 (L1) and 72 (L2) hours after the last ovalbumin challenge. Measurements of resistance and elastance were obtained before and after ovalbumin challenge in C and ER groups and before and after Acetylcholine challenge in all groups. Using morphometry, we assessed the density of eosinophils and smooth muscle cells, as well as collagen and elastin content in lung strips. The baseline and post-agonist values of resistance and elastance were increased in ER, L1 and L2 groups compared with C (p = 0.001). The morphometric analysis showed an increase in alveolar eosinophil density in ER and L2 groups compared with C group (p < 0.05). There was a significant correlation between eosinophil density in parenchymal strips of C, L1 and L2 groups and values of resistance and elastance post-Acetylcholine (r = 0.71, p = 0.001 and r=0.74, p < 0.001, respectively). The results show that the lung parenchyma is involved in the late response of this guinea pig model of chronic allergic inflammation and the constriction response in this phase is related to the eosinophilic inflammation.
143

Aspectos acústicos da domesticação: os chamados de alerta e de corte do preá Cavia aperea e da cobaia Cavia porcellus. / Acoustic aspects of domestication: vocal signals of alarm and courtship in wild and domestic cavies.

Patrícia Ferreira Monticelli 28 July 2000 (has links)
A comparação entre cobaias (Cavia porcellus) e preás (Cavia aperea) fornece dados relevantes para se entender o processo de domesticação (Künzl e Sachser, 1999). No presente trabalho, foram registradas e analisadas sonograficamente (1) a vocalização de alerta, drr, em cobaias e em duas amostras de preás, uma observada em Münster (Alemanha), constituída de animais provenientes da Argentina, e outra constituída de animais provenientes de Itu (São Paulo) e (2) a vocalização de corte, purr, em cobaias e preás de Münster. Encontrou-se diferenças significativas entre C. porcellus e ambas as populações de C. aperea nos parâmetros temporais do drr (duração dos pulsos e dos intervalos entre eles e taxa de emissão) assim como diferenças significativas entre as populações de preás de Münster e de Itu (freqüências mínima e máxima da fundamental e freqüência máxima do chamado). No caso do purr, também houve diferenças significativas nos parâmetros temporais das espécies. Estes resultados demonstram a influência da domesticação e de fatores ecotípicos sobre a comunicação vocal e podem, juntamente com a análise sonográfica dos chamados de outras espécies do gênero Cavia, servir para resolução de questões filogenéticas deste grupo. Estudos com playbacks cruzados poderão eventualmente mostrar em que medida as diferenças de vocalização afetam o comportamento social e reprodutivo dos animais. / Comparision of guinea pigs (Cavia porcellus) and wild cavies (C. aperea) provides privileged models for the understanding of the behavioral effects of domestication (Künzl & Sachser, 1999). We here present a comparision between alarm (drr) and courtship (purr) vocalizations in domestic and wild types of cavies. We recorded and analyzed sonographically such calls in guinea pigs from our laboratory stock and in two samples of wild cavies, one from Münster University (Germany), bred from individuals captured in Argentina, and one from Itu (State of São Paulo). There were significant differences between domestic and both wild cavies samples in the temporal features of the drr (pulse duration, interpulse interval duration and rate of emission) and between the Münster and Itu samples in frequency related features (minimum and maximum freqüencies of the fundamental and maximum frequency of the call). Courtship calls purr of domestic and wild cavies from Münster also differed in temporal acoustical features. Our results show that both domestication and ecotypic factors may influence vocal communication. Playback studies could eventually show to what extent there is interspecific discrimination of the acoustic features of the alarm and courtship calls of cavies.
144

Behavioral Induction in Guinea Pigs as a Function of Reinforcement Magnitude in Multiple Schedules of Negative Reinforcement

Burns, Dennis L. 01 May 1975 (has links)
The purpose of this study was to examine the effects of changes in magnitude of negative reinforcement on multiple schedules with the guinea pigs. In both schedule components, the first response (lever press) after an average of 10 seconds was reinforced. In the constant component of this schedule the reinforcement magnitude (time-off from electric foot shock) was always 15 seconds; whereas, in the manipulated component the magnitude changed in the following sequence: 15, 7.5, 15, 30, and 15 seconds. All subjects showed a gradual decrease in response rate across baseline conditions. When behavioral effects were evaluated relative to this changing baseline, five of six subjects demonstrated that as the reinforcement magnitude decreased in one component, the response rates in both components decreased (negative induction). Likewise, when reinforcement magnitude increased in one component, all subjects showed behavioral induction. Specifically, three subjects showed increases in response rate in both components (positive induction), while two subjects showed decreases in response rate in v both components (negative induction). This research extends the generality of the behavioral induction phenomena on multiple schedules to in elude negative reinforcement with the guinea pig as a function of changes in reinforcement magnitude
145

Study of livestock production levels in three communities near the city of Riobamba

Nuñez Lopez, Raul Rolando 01 January 1997 (has links) (PDF)
This study was done by administering household surveys to 50% of the families in the three communities. Families were selected through stratified random sampling. This allowed us to determine how much families are exploiting species that have a significant level of production as well as whether they use them for a commercial activity or subsistence. With regard to cows, 60.40 ± 4.72% of families use them. Each family has an average of 1.68 ± 0.21 cows. Productive cows make up 36.9% of the above percentage, which is a majority. The measured rate of production was 6.48 ± 0.25 L/cow/day. Overall, 40.16 ± 3.17% of production was used for household consumption while the rest was sold. These parameters as well as the sale of live animals helped San Nicolas have an annual income of 735 US dollars, which shows that this community relies more on commercial activity. On the other hand, San Clemente and San Francisco had annual incomes of 367 and 279 US dollars respectively. This shows that these communities focus more on familial subsistence. Of the major species, sheep are the least exploited with 54.80 ± 8.74% of families using them. The first lambing occurs at 17.79 ± 0.48 months. Newborns are weaned at 5.57 ± 0.11 months by only 27.27 ± 4.47% of families. Of the weaned newborns, 60.69 ± 5.13% are kept and the rest are sold. Every 10.46 ± 0.47 months, 77.96% of the wool produced is sold. Generally, the sheep are sol d at 22.84 ± 1.75 months of age. This generates an average annual income of 40.85 ± 19.26 US dollars, which indicates that this activity is focused on familial subsistence. Swine production is the most common form of animal production. Pigs are exploited by 81.86 ± 7.17% of families with each family having an average of 2.11 ± 0.16 animals. A sow’s first delivery occurs at 16.48 ± 0.48 months and their productive life comes after reproducing 1.98 ± 0.15 times. Each litter has 5.72 ± 0.19 offspring with a post-weaning mortality rate of 28.99 ± 4.82%. Offspring are weaned at 2.90 ± 0.12 months. Overall, 65.13% of the weaned offspring are kept and the rest are sold. Annual revenue from pig production is 63.2 ± 22.46 US dollars which indicates it is used for familial subsistence, acting as a safeguard against economic emergencies at times. Of the minor species, the guinea pig is the most exploited. It is used by 86.11 ± 3.65% of families with each family having an average of 12.04 ± 1.31 guinea pigs. The mothers have an average of 2.44 ± 0.06 offspring per litter with a weaning rate of 75.81 ± 4.33%. Overall, 86.91% of production is used for family consumption and the rest is sold. The annual income generated by this activity is 6.24 ± 0.51 US dollars which indicates that this is an activity dedicated to providing food for the family. Rabbits are used by 49.42 ± 5.23% of families, each having an average of 4.03 ± 0.64 animals. There is an average of 6.57 ± 0.29 newborns per litter with a weaning rate of 41.16 ± 5.20%. Overall, 80.18 ± 4.16% of production is used for family consumption. This activity is similar to guinea pig production seeing as the annual income it generates is only 12.80 ± 1.10 US dollars. Chickens are exploited by 77.33 ± 4.39% of families with each family having an average of 5.88 ± 0.60 animals. Broiler chickens make up 48.22% of the poultry population with the rest being made up of native and field hens. Overall, 68.96% of broiler chickens are used for family consumption while 89.31 ± 3.27% of hens are used for family consumption. The annual income from this activity is 40.13 ± 19.24 US dollars. This makes it appear to have a slight tendency toward commercial use. We conclude that the three communities have different levels of animal exploitation. San Nicolas was the most successful of the three, partially using their livestock production for commercial purposes. San Clemente used part of theirs for commercial purposes as well, but on a lower scale. San Francisco, on the other hand, focuses their livestock production solely on familial subsistence. We recommend that a study be conducted regarding all points involved in the feasibility of production projects in these communities, especially in regard to the organization in each community. This will help improve production levels and make way for a change from a subsistence based economy to a more commercially based economy, ultimately improving the social and nutritional levels of these families.
146

Persisiting Sensitization of Depressive-Like Behavior and Thermogenic Response During Maternal Separation in Pre- and Post Weaning Guinea Pigs

Schneider, Randi Lynn 14 July 2011 (has links)
No description available.
147

Maturation and aging of the retina in normal and night blind albino guinea pigs : a structural and functional study

Racine, Julie. January 2007 (has links)
No description available.
148

Postnatal vitamin D supplementation normalizes neonatal bone mass following maternal dietary vitamin D deficiency in the guinea pig

Finch, Sarah L. January 2007 (has links)
No description available.
149

Diet enrichment with arachidonic and docosahexaenoic acid during the lactation period attenuates the effects of intrauterine growth restriction from birth to maturity in the guinea pig and improves maternal bone mass

Burr, Laura Lynn. January 2008 (has links)
No description available.
150

The Immune Response of Guinea Pigs as Influenced by Hypobaric Pressure and Normoxic Environment (Part I); Membrane Filter-Fluorescent-Antibody Method for Detection and Enumeration of Bacteria in Water (Part II)

Reeder, Dennis James 08 1900 (has links)
In this work experimental design and tests were established to determine whether antibody production in guinea pigs injected with a bacterial antigen is Influenced by the environment of simulated high altitude with normoxic conditions. Hematological and electrophoretic studies were simultaneously run with the antibody determinations as a check on related responses of the animals.

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