Includes bibliographical references (leaves 183-207) / ix, 207 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / A local intradermal technique using colchicine to estimate cell division rate in wool follicles is refined and used throughout the thesis. Statistical methods used to analyse data obtained with this method are described and discussed. The implications of the findings are of great significance to research into the influence of physiological changes on wool production, and suggest experiments should be conducted under controlled environmental conditions, with a minimum of stress imposed on the animals. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences, 1992

Background: Despite the recent improvements in surgical techniques and postoperative patient care, atrial fibrillation (AF) remains the most frequent complication after cardiac surgery. Although postoperative AF is often regarded as a benign clinical condition, this arrhythmia has significant adverse effects on patient recovery and postoperative survival. Its exact pathophysiology has not yet been elucidated. The present thesis aims to analyze AF risk factors and their interaction, pre-existing histological explanatory alterations of the atrium, the AF impact on postoperative survival and the compliance of a prophylactic drug regimen. Methods: During a 10-year period, consecutive cardiac surgery cases with complete data on AF occurrence and postoperative survival were extracted. All patients were operated on for coronary or valvular surgery, with cardiopulmonary bypass (CPB). Hospital and long-term survival data were obtained from Swedish population registry. Study I) Isolated coronary artery bypass grafting (CABG, n=7056), aortic valve replacement (n=690) and their combination (n=688) were considered. Independent AF risk factors and AF effects on early and 1 year mortality were investigated. Study II) Patients affected by postoperative AF among isolated CABG patients (n=7621), valvular surgeries (n=995) and their combination (n=879) were studied. Long-term survival was obtained and prognostic factors identified. Study III) Seventy patients were randomized to on-pump (n=35) or off-pump (n=35) CABG. Samples from the right atrial appendage were collected and histology was evaluated by means of light and electronic microscopy with reference to preexistent alterations related to postoperative AF. Study IV) Cardiac surgery patients with complete data on smoking status (n=3245) were reviewed. Effects of smoking on AF development and interaction among variables were explored. Study V) CABG patients without clinical contraindications to receive oral sotalol (80 mg twice daily) and magnesium were prospectively enrolled (n = 49) and compared with a matched contemporary control CABG group (n = 844). The clinical compliance to the AF prophylactic drug regimen was tested. Results: The overall AF incidence was around 26%, subdivided into 23%, 40% and 45% for isolated CABG, valve procedures and their combined surgeries, respectively. Age was the strongest predictor of postoperative AF. Coronary disease superimposed risk factors with reference to myocardial conditions at CPB weaning. Considering the preoperative smoking condition, smokers demonstrated a reduced AF incidence compared to non-smokers (20% versus 27%, p<0.001). An interaction between smoking status and inotropic support was observed: without this interaction smoking conferred a 46% risk reduction of AF (p=0.011). At the histological level, myocyte vacuolization and nuclear derangement represented anatomical independent AF predictors (p=0.002 and p=0.016, respectively). CPB exposure was not associated to postoperative AF nor histological changes. Although, postoperative AF increases the length of hospitalization in all patient groups, it did not affect the hospital survival. However, AF independently impaired the late survival, a phenomenon seen in the CABG group only. With reference to the tested sotalolmagnesium drug regimen, only 55% of CABG patients were compliant to the treatment, with marginal effects on AF occurrence. Conclusions: In addition to age, details at the CPB weaning period, pre-existing histopathological changes, the hyperadrenergic state and catecholamines are key mechanisms in the pathophysiology of postoperative AF. In particular, the CPB period hides valuable information for timely AF prophylactic stratifications. Further, compliance effects due to patient selection should also be considered in a prophylactic therapy model. Postoperative AF increases late mortality after isolated CABG surgery, but not after valvular procedures. Although the mechanisms are unclear, our results draw the attention to possible AF recurrence after hospital discharge, indicating a strict postoperative surveillance.

No description available.

A sepse grave e o choque séptico são complicações decorrentes de um processo infeccioso, associados à alta mortalidade em UTI e caracterizados por disfunção cardiovascular, renal e metabólica. A terapia farmacológica (TF) visa oferecer suporte hemodinâmico e reduzir níveis glicêmicos. Nesse cenário, o presente estudo objetivou analisar o impacto da TF e da alteração glicêmica na evolução clinica do paciente em sepse grave e choque séptico nas primeiras 72 horas.Trata-se de um ensaio clínico controlado randomizado em que os pacientes (n=46) foram alocados em grupos glicêmicos intensivo (manutenção da glicemia entre 80-110mg/dl) e convencional (manutenção da glicemia entre180-220mg/dl). Os dados foram coletados no período de 2004-2006 em um Hospital Universitário do Município de São Paulo. Na análise estatística foram usados os testes t-student, Qui-Quadrado, sendo considerados significativo p<0,05. Os resultados mostraram que a amostra foi constituída por pacientes do sexo masculino (58,7%), clínicos (78,3%) que apresentaram choque séptico (78,3%) decorrente de infecções no sistema respiratório (39,1%), com disfunção cardíaca (36,9%) e que apresentaram lesão renal aguda (56,5%). A média de idade foi de 51,6 anos. Os medicamentos de suporte mais prescritos foram noradrenalina (69,6%; 56,5%), hidrocortisona (56,5%;67,4%) e insulina (67,4%;73,9%), nas 24 e 48 h. Na comparação entre os grupos, observou-se diferença estatisticamente significante (p=0,00) na média glicêmica; não houve diferença estatisticamente significantes para as variáveis FC mínima (p= 0,68), máxima (p=0,11), PAM mínima (p=0,06) e máxima (p=0,11), no DU (p=0,23), Cr (p=0,33), volume infundido de cristalóides (p=0,10) e na mortalidade (p=0,11). A instabilidade hemodinâmica no grupo convencional foi mais duradoura e os óbitos ocorreram, apenas, entre os pacientes alocados no grupo convencional. Dessa forma, os dados sugerem que o controle glicêmico intensivo favorece o restabelecimento hemodinâmico de pacientes em choque séptico e, de certo modo, os protege do desfecho mortalidade / Severe sepsis and septic shock are complications that develop from an inflammatory process leading to high mortality in the intensive care unit (ICU) and characterized by cardiovascular, renal and metabolic dysfunction. The pharmacological therapy (PT) aims at offering hemodynamic support and at reducing glycemic levels. In this scenario, the present study had the objective of analyzing the impact of PT and of the glycemic alteration in the clinical evolution of severe sepsis and septic shock patients in the first 72 hours. This is a randomized control trial in which the patients (n=46) were divided into intensive glycemic group (maintenance of glycemia between 80-110mg/dl) and conventional glycemic group (maintenance of glycemia between 180-220 mg/dl). The data were collected in the 2004-2006 period in a University Hospital in the city of São Paulo. In the statistical analysis, the tests used were t-student, Qui-Quadrado, being considered meaningful p<0,05. The results showed that the sample was formed by male patients (58.7%), clinical patients (78.3%) that presented septic shock (78.3%) as a result of infection in the respiratory system (39.1%), with cardiac dysfunction (36.9%) and those that presented acute renal lesion (56.5%). The average age was 51.6 years. The most commonly prescribed support drugs were noradrenaline (69.6%, 56.5%) and hydrocortisone (56.5%, 67.4%) in the first 24 and 48 hours. In the comparison between groups, statistically significant difference was observed (p=0,00) in the glycemic average, there was no statistically significant difference for the variables: minimal FC (p=0,68), maximum (p=0,11), minimum PAM (p=0,06) and maximum (p=0,11), DU (p=0,23), CR (p=0,33), volume infundido de cristalóides (p=0,10) and mortality (p=0,11). The hemodynamic instability in the conventional group lasted longer and deaths occurred only among the conventional group patients. Therefore, the data suggest that the intensive glycemic control favors the hemodynamic recovery of septic shock patients and, in a way, protects them from death

Orientadores: Jose Wilson Magalhães Bassani, Rosana Almada Bassani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-06T07:47:18Z (GMT). No. of bitstreams: 1 Boer_DenileCominato_M.pdf: 557480 bytes, checksum: e378c01e865d04a595d3f0e7ad3c60dd (MD5) Previous issue date: 2006 / Resumo: Embora haja demonstração de que a estimulação simpática tenha efeito facilitatório sobre a indução de atividade espontânea em miocárdio há controvérsia sobre a participação dos tipos de adrenoceptores na mediação deste efeito. No presente trabalho, descrevemos um método desenvolvido para determinação, em átrio esquerdo isolado (AE) de rato, da relação concentração-efeito para agentes que exercem efeito arritmogênico por aumento da mobilização celular de 'Ca POT. 2+¿. O método baseou-se na interposição de pausas estimulatórias, durante as quais registraram-se contrações espontâneas (CE), precedidas ou não por trens estimulatórios de alta freqüência (5 Hz). O protocolo estimulatório foi repetido na presença de diferentes concentrações de agonistas. Para cada concentração de agonista, a resposta arrítmica foi considerada como a soma dos números de CE/min, no total de preparações. Foi analisada também a resposta inotrópica, como sendo o incremento de força ou encurtamento de pico, desenvolvidos em AE e miócitos ventriculares (MV), respectivamente. A relação foi ajustada por uma função sigmóide para cálculo de Min (i.e., valor da variável na ausência do agonista), Rmax (resposta máxima) e pD2 (-log da concentração do agonista que produziu uma resposta igual a 50% de Rmax). Este método foi aplicado no estudo dos tipos de adrenoceptores envolvidos na resposta arrítmica a catecolaminas em AE e MV. A Rmax inotrópica à ativação de adrenoceptores 'alfa IND. 1¿ + 'beta IND. 1¿ foi comparável àquela por ativação de apenas receptores 'beta IND. 1¿, em ambos AE e MV. Já a ativação de adrenoceptores 'alfa IND. 1¿ produziu uma Rmax inotrópica de apenas metade daquela observada pela estimulação 'alfa IND. 1¿ + 'beta IND. 1¿. Da mesma forma, a resposta arrítmica foi semelhante para estimulação de adrenoceptores a1+ß1 e de apenas receptores 'beta IND. 1¿. Entretanto, nenhuma resposta foi obtida pela estimulação de receptores adrenérgico do tipo 'alfa IND. 1¿. Estes resultados indicam que a estimulação de adrenoceptores 'alfa IND. 1¿, apesar de evocar uma resposta inotrópica positiva em ambos AE e MV, não é arritmogênica. A ativação do tipo 'beta¿, por outro lado, parece ser a principal via para estimulação inotrópica simpática e na indução de arritmias. Além disso, concluímos que parece existir antagonismo funcional entre os subtipos de adrenoceptores 'beta¿, manifestado por ações pró- e anti-arrítmicas dos subtipos 'beta IND. 1¿ e 'beta IND. 2¿, respectivamente, em miocárdio (tanto atrial, quanto ventricular) de rato / Abstract: Although it has been shown that sympathetic stimulation facilitates the appearance of myocardial spontaneous activity, it is still not clear which types of adrenoceptors mediate this effect. In this study, we describe a method developed for determination, in isolated rat atria (AE), of the concentration-effect relationship for arrhythmogenic agents that act via promotion of cell 'Ca POT. 2+¿ overload. The method was based on the interposition of stimulatory rest periods, during which spontaneous contractions (CE) were recorded, preceded or not by high frequency (5 Hz) stimulus trains. The stimulation protocol was applied at each agonist concentration, and the arrhythmic response was taken as the sum of the number of CE/min in all preparations. The positive inotropic response was considered as the agonist-dependent increment of developed force or peak shortening in AE and isolated ventricular myocytes (MV), respectively. Concentration-effect curves were determined by fitting a sigmoid function, from which the following parameters were estimated: Min (i.e., value of the variable in the absence of the agonist), Rmax (maximal response) e 'pD IND. 2¿ (-log of the molar agonist concentration that evokes a response equal to 50% of Rmax). This method was applied to investigate the adrenoceptor types involved in the mediation of catecholamine-induced arrhythmogenesis in AE and MV. Inotropic Rmax to activation of 'alfa IND. 1¿ + 'beta IND. 1¿ adrenoceptors was comparable to that of activation of solely 'beta IND. 1¿ adrenoceptors in both AE and MV. However, Rmax to selective 'alfa IND. 1¿ adrenoceptor activation was only half of that produced by 'alfa IND. 1¿ + 'beta IND. 1¿ adrenoceptor stimulation. The arrhythmic responses to 'alfa IND. 1¿ + 'beta IND. 1¿ and 'beta IND.1¿ receptor stimulation were similar, but selective a1 adrenoceptor activation was unable to evoke any spontaneous activity. The results indicate that a1 adrenoceptors, although able to mediate stimulation in both AE and MV, are not involved in arrhythmogenesis. 'beta¿-adrenoceptor activation, thus, seems the main type involved in both inotropic and arrhythmic responses to catecholamines. In addition, our results point out a functional antagonism between 'beta¿-adrenoceptor subtypes: i.e., pro- and anti-arrhythmic effects mediated by 'beta IND. 1¿ and 'beta IND. 2¿-adrenoceptors, respectively in both atrial and ventricular rat myocardium / Mestrado / Engenharia Biomedica / Mestre em Engenharia Elétrica

O núcleo pré-mamilar dorsal (PMd), de crucial importância para expressão do comportamento de defesa exibido por roedores durante o confronto com predador natural, odor ou contexto associado, representa o sítio hipotalâmico com maior aumento no número de células imunorreativas a proteína Fos após o confronto predatório. Estudos mostram que a mediação noradrenérgica central é crítica para a expressão das respostas de medo e que tanto as respostas incondicionadas como as contextuais ao odor do gato dependem de sua ação central, mediada pelo PMd. Dada a importância da modulação noradrenérgica no PMd para a expressão das respostas anti-predatórias, investigamos quais grupamentos catecolaminérgicos aferentam o núcleo empregando técnicas de rastreamento retrógrado somado a técnica de imunofluorescência (dupla-marcação). Nossos resultados revelaram que a única fonte de aferência catecolaminérgica para o PMd é oriunda do locus ceruleus, onde encontramos um número conspícuo de células duplamente marcadas, indicando ser este o responsável pelo suporte noradrenérgico ao PMd. / Evidence suggests the medial hypothalamic defensive system plays a pivotal role in processing of predator-derived and contextual-related cues. Fear responses to predatory threats rely heavily on the PMd beta adrenergic neurotransmission. Thus, it has been shown that propranolol significantly reduced PMdFos expression in response to cat odor, and that beta adrenoceptor blockade, in the PMd, reduced defensive responses to both cat odor exposure and cat odor-related context. Given the importance of the noradrenergic innervation of the PMd to the expression of unconditioned and learned fear responses, we have presently investigated the putative noradrenergic source of inputs to the nucleus. To this end, we have combined Fluoro-Gold retrograde tract-tracing and catecholamine immunostaining, and found that the locus ceruleus is seemingly the only source of catecholaminergic source of inputs to the PMd. In addition, the present findings are particularly interesting given the well-documented roles of the locus ceruleus roles in attentional processes.

INTRODUÇÃO: Não são conhecidos os mecanismos que determinam o comportamento da pressão arterial durante o sono. OBJETIVO: Investigar o papel do sistema nervoso simpático, do sistema renina-angiotensinaaldosterona e da excreção de sódio urinário no descenso da pressão arterial durante o sono. MÉTODOS: Hipertensos e normotensos foram submetidos a duas monitorizações ambulatoriais de pressão arterial (MAPA)/24h com SpaceLabs 90207, medidas de 15/15 minutos durante a vigília e de 20/20 minutos no período de sono. Na ocasião da MAPA 1 foram submetidos às dosagens laboratoriais de atividade de renina (ARP), aldosterona e catecolaminas plasmáticas e excreção em diurese de 24h de sódio (Na+u), potássio (K+u) e creatinina. Após o período médio de 50 ± 20 (média ± DP) dias a MAPA e as dosagens foram repetidas. RESULTADOS: Foram incluídos 35 hipertensos e 24 normotensos, com idade 56 ± 12 anos, 45 mulheres e 42 com cor da pele branca. Não houve diferença nos parâmetros laboratoriais na ocasião da MAPA 1 e da MAPA 2 nos normotensos e hipertensos. Mantiveram o mesmo comportamento de descenso da pressão sistólica e diastólica durante o sono nas duas MAPAs (>= 10% ou < 10%) 29 (49%) indivíduos, denominado grupo manteve (hipertensos n = 18). Mudaram o comportamento do descenso durante o sono da pressão sistólica ou diastólica (de >= 10% para < 10% ou de < 10% para >= 10%) 30 (51%) indivíduos, denominado grupo mudou (hipertensos n = 17). O grupo \"mudou\" apresentou menor Na+u na ocasião da MAPA 2 (145 ± 65 mEq/24 h vs 120 ± 46 mEq/24 h, p = 0,04). Houve correlação positiva entre: a) a diferença do descenso da pressão sistólica e a diferença dos resultados das dosagens de Na+u (r = 0,41; p = 0,01) realizadas nas MAPAs 1 e 2 em todos os indivíduos dos grupos \"manteve\" e \"mudou\"; b) a diferença do descenso da pressão sistólica e a diferença de Na+u/creatinina urinária (r = 0,67; p = 0,03) e de L dopa plasmática (r = 0,75; p = 0,003) realizadas nas MAPAs 1 e 2 no grupo \"manteve\" (>= 10%); e c) a diferença do descenso da pressão sistólica e a diferença do resultado das dosagens de ARP/Na+u realizadas nas MAPAs 1 e 2 (r = 0,81; p = 0,03) no grupo \"manteve\" (< 10%). CONCLUSÃO: Em hipertensos e normotensos, sem intervenção medicamentosa ou dietética, a diferença do descenso da pressão sistólica durante o sono entre duas MAPAs apresenta correlação positiva com a diferença da excreção de sódio urinário / INTRODUCTION: The mechanisms which determine the pattern of blood pressure during sleep are unknown. OBJECTIVE: To investigate the role of the sympathetic nervous system, renin-angiotensin-aldosterone system and urinary sodium excretion in the nocturnal blood pressure fall. METHODS: Hypertensive and normotensive subjects were submitted to two ambulatorial blood pressure monitorings (ABPM)/24h with a SpaceLabs 90207 equipment programmed to obtain measurements 15/15 minutes while awake and 20/20 minutes during sleep. Upon the ABPM 1, they were submitted to laboratory measurements of plasma renin activity (PRA), plasma aldosterone and catecholamines, as well as of the excretion of sodium (UNa+), potassium (UK+) and creatinine in 24-h-diuresis. After a mean period of 50 ± 20 days, the ABPM and the laboratory measurements were repeated. RESULTS: Included in the study were 35 hypertensive and 24 normotensive subjects, aged 56 ± 12 years, of which 45 were females and 42 Caucasian. There was no difference in the laboratory parameters measured upon ABPM 1 or 2, in either normotensive or hypertensive subjects. The same pattern of nocturnal systolic and diastolic pressure fall was maintained in both ABPMs (>=10% or <10%) by 29 (49%) subjects, named the \"maintained\" group (hypertensive n = 18). The nocturnal systolic or diastolic pressure fall changed (from >=10% to <10% or from <10% to >=10%) in 30 (51%) subjects, named the \"changed\" group (hypertensive n = 17). The \"changed\" group showed a smaller UNa+ upon the ABPM 2 (145 ± 65 mEq/24 h vs 120 ± 46 mEq/24 h; p = 0.04). There was a positive correlation between the difference in the nocturnal systolic pressure fall and the difference in the results of the UNa+ (r = 0,41; p = 0,01) measurements performed upon ABPM 1 and 2 in the normotensive or hypertensive subjects of the \"maintained\" and \"changed\" groups; b) the difference in the nocturnal systolic pressure fall and the difference in the measurements of UNa+/creatinine excretion (r = 0.67; p = 0.025) and plasma L dopa (r = 0.75; p = 0.003) carried out upon ABPM 1 and 2 in the \"maintained\" group (>=10%); and c) the difference in the nocturnal systolic pressure fall and the difference in the results of the PRA/UNa+ measurements performed upon ABPM 1 and 2 (r = 0.81; p = 0.03) in the \"maintained\" group (<10%). CONCLUSION: In hypertensive and normotensive individuals, without any pharmacological or dietary intervention, the difference in the nocturnal systolic pressure fall between the two ABPMs shows a positive correlation with the difference in urinary sodium excretion

Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-04-27T15:54:57Z No. of bitstreams: 1 luizcarlosdecairesjunior.pdf: 1316351 bytes, checksum: e029591c37abc938d7247930a9c7cd15 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-12T15:50:45Z (GMT) No. of bitstreams: 1 luizcarlosdecairesjunior.pdf: 1316351 bytes, checksum: e029591c37abc938d7247930a9c7cd15 (MD5) / Made available in DSpace on 2017-05-12T15:50:46Z (GMT). No. of bitstreams: 1 luizcarlosdecairesjunior.pdf: 1316351 bytes, checksum: e029591c37abc938d7247930a9c7cd15 (MD5) Previous issue date: 2014-08-22 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O sistema de telecomunicação móvel tem crescido ao longo dos anos. A comunidade científica tem demonstrado uma crescente preocupação sobre os possíveis efeitos da exposição à radiação electromagnética de radiofrequência (RFEMR) emitida por dispositivos móveis sobre a saúde dos usuários. Este estudo teve como objetivo avaliar os efeitos da RF-EMR sobre a via de MAPKs, verificando os níveis de fosforilação das enzimas MEK 1 / 2 e ERK 1 / 2, em células do hipotálamo e hipófise, sobre a secreção de catecolaminas, nível de glicose sérica, consolidação da memória de longo prazo e estabelecimento de comportamento de ansiedade. Ratos Wistar machos, com 60 dias de idade, foram expostos à radiação emitida pelos telefones celulares (1,8 GHz) em condições agudas (1 e 3 horas de exposição) e crônicas (3 e 10 noites de exposição). Os níveis de fosforilação de MEK 1 / 2 e ERK 1 / 2 foram alterados em células hipotalâmicas de animais expostos por 1 hora. Após 3 horas, 3 noites e 10 noites, foi observada alteração somente no nível de fosforilação das enzimas MEK 1 / 2, em células hipotalâmicas; e nenhuma alteração foi constatada na fosforilação das enzimas MEK 1 / 2 e ERK 1 / 2, em células hipofisárias. As exposições por períodos agudos promoveram aumento da secreção basal de catecolaminas e a glicemia foi alterada após 1 hora e 10 noites. Não foi constatado comportamento estado de ansiedade pelo teste de cruz elevada em quaisquer períodos de exposição. Porém, a exposição crônica, por 10 noites, aumentou a secreção de catecolamina, estimulada por cafeína, concomitantemente à diminuição a glicemia, podendo afetar a consolidação da memória. Os resultados sugerem que a exposição de ratos a campos electromagnéticos emitidos por celulares é capaz de alterar a via de MAPKs, mudar o perfil de secreção basal e estimulada de catecolaminas, de glicemia, além de afetar a consolidação de memória de longo prazo. / The mobile telecommunication system has grown over the years. There has been a growing concern about the possible effects of exposure to radiofrequency electromagnetic radiation (RF-EMR) emitted by mobile devices on the health of users. This study aimed to evaluate the effects of whole-body RF-EMR exposure on MAPK's pathway, verifying the phosphorylation levels of MEK 1 / 2 and ERK 1 / 2, in hypothalamus and pituitary cells, catecholamine secretion, serum glucose, long-term memory consolidation and anxiety-like behavior occurrence. Male Wistar rats, 60 days old, were subjected to electromagnetic waves emitted by mobile phones (1.8 GHz) in acute (1 and 3 hours of exposure) and chronic (3 and 10 nights of exposure) conditions. The phosphorylation levels of MEK 1 / 2 and ERK 1 / 2 changed in hypothalamus cells after 1 hour of exposure. After 3 hours, 3 nights and 10 nights, we have found changes only in phosphorylation of MEK 1 / 2 (hypothalamus); no changes were found in MEK 1 / 2 and ERK 1 / 2 from pituitary cells. The acute exposures lead to the increase of basal catecholamine secretion and the glycemia changed after 1 hour and 10 nights. On the other hand, the chronic exposure increased the catecholamine release, by caffeine stimulation, but decreased the serum glucose level, disturbing the memory consolidation. The results suggest that exposure of rats to electromagnetic fields emitted by mobile phones is able to change the MAPK's pathway, profile of basal and stimulated secretion of catecholamines, and serum glucose level besides affecting long-term memory.

No / The biochemistry of hair pigmentation is a complex field involving a plethora of protein and peptide mechanisms. The in loco factory for melanin formation is the hair follicle melanocyte, but it is common knowledge that melanogenesis results from a fine tuned concerted interaction between the cells of the entire dermal papilla in the anagen hair follicle. The key enzyme is tyrosinase to initiate the active pigmentation machinery. Hence, an intricate understanding from transcription of mRNA to enzyme activity, including enzyme kinetics, substrate supply, optimal pH, cAMP signaling, is a must. Moreover, the role of reactive oxygen species on enzyme regulation and functionality needs to be taken into account. So far our knowledge on the entire hair cycle relies on the murine model of the C57BL/6 mouse. Whether this data can be translated into humans still needs to be shown. This article aims to focus on the effect of H2O2-redox homeostasis on hair follicle pigmentation via tyrosinase, its substrate supply and signal transduction as well as the role of methionine sulfoxide repair via methionine sulfoxide reductases A and B (MSRA and B).

Student Number: 0218322F Master of Science School of Physiology / The high morbidity and mortality of wild mammals and livestock during capture and transport is generally ascribed to thermal stress. Consequently, capture operators can benefit from improved methods that may reduce thermal stress. The aim of my study was to develop a practical method of measuring the body temperature of mammals during capture and transport operations. Firstly, I determined whether intermittent temperature recordings, which allow for minuteby- minute monitoring of an animal’s temperature, could accurately reflect continuous measures of an animal’s rectal temperature. Intermittent temperatures were measured via telemetry while continuous and off-line recordings were measured with data loggers. Secondly, I compared rectal and abdominal temperatures to determine if rectal temperature can provide a practical, noninvasive method of estimating core body temperature. Additionally, I measured body temperature and environmental conditions throughout transportation and compared pre- and post-transport levels of faecal cortisol, and blood cortisol, haematocrit and catecholamines. Measuring rectal temperatures seems to be the only feasible, non-invasive technique to obtain temperature during transport operations. However, rectal temperature records required about 30 minutes to stabilise after inserting a thermometric device. After rectal temperature stabilised, generally the difference between abdominal and rectal temperatures varied greatly for individual animals, while the average differences in temperatures between the body sites were not significant for all, except one, species. I have also shown that telemeters and data loggers can be used interchangeably to measure the body temperature of animals. The differences between temperatures measured by the devices were not significant, except for substantial differences shown in two animals. The addition of earphones and a large aerial inside the vehicle improved the telemetry results, by limiting the extraneous noise of the capture and transport environment. These conditions probably caused the anomalous readings in the two animals. General thermal responses to stress are that animals showed a peak in temperature due to capture and a decrease in temperature during transport. Therefore, capture-related stress and the likelihood of animals dying during capture could be minimised by ensuring that the animals are not chased longer than a set cut-off time. Further, globe temperature should be monitored to ensure that animals are not captured in high thermal conditions. In contradiction with the current guidelines regarding the appropriate time of day for capture, I recommend that animals should not be caught at the end of the day, as my results show that this is when their body temperatures are the highest. Body temperatures during transport and differences in faeces cortisol before and after transport seem to indicate that animals adapt to repeated stress events.