Thesis (doctoral)--Universität zu Köln, 1991. / Includes bibliographical references (p. 368-431) and index.

Colorectal cancer (CRC) remains the second deadliest cancer in the United States, despite steady reduction in mortality rate over the last three decades. Colonoscopy is the gold-standard screening modality with high sensitivity and specificity to mature polyps. However, the miss rate for small (<5 mm) lesions is estimated to be as high as 26%. Because the five-year survival rate for CRC detected at the local stage is 90%, there is a clear need for a screening procedure that is sensitive to these small lesions. Optical coherence tomography (OCT) has become a major biomedical imaging modality since its invention in 1991. As the optical analog to ultrasound, OCT provides information in both lateral and depth dimensions with resolution < 10 µm and an imaging depth of about 1.5 mm in scattering tissue. In this dissertation, I describe my efforts to develop new uses of OCT for improved early detection of adenoma in the azoxymethane mouse model of CRC. In recent years, commercial OCT systems have reached imaging speeds sufficiently high for in vivo volumeric imaging while laterally sampling the tissue at the Nyquist limit. First, I describe the design of a miniature endoscope and the integration of this probe with a commercial OCT system. Then I describe the development of two OCT imaging methods, one structural and one functional, that could be used for future work in diagnostic or therapeutic studies. The structural method produces en face images of the colon surface showing the colonic crypts, the first such demonstration of crypt visualization in the mouse. Changes in the crypt pattern are correlated with adenoma and are one of the earliest morphological changes. The functional method uses a Doppler OCT algorithm and image processing to detect the colon microvasculature. This technique can be used for vessel counting and blood flow measurements. Angiogenesis occurs at the beginning of tumorigenesis, and the tumor-originated arterioles are incapable of regular vasodilation. This Doppler OCT technique could potentially detect tumors at the earliest stages by measuring the change in local blood flow velocity in response to vasodilatory stimuli.

CoordenaÃÃo de AperfeiÃoamento de NÃvel Superior / O cÃncer colorretal (CCR) à a quinta neoplasia mais incidente no Brasil e sua freqÃÃncia vem aumentando em paÃses industrializados. A lesÃo prÃ-neoplÃsica mais precoce com presenÃa de displasia à o foco de cripta aberrante (FCA), estando relacionada como lesÃo precursora de adenomas colorretais e cÃncer em humanos. O entendimento destas lesÃes à fundamental para esclarecer os mecanismos da carcinogÃnese colorretal e sua prevenÃÃo. O objetivo foi verificar se a dieta hipercalÃrica (DH), hiperlÃpidica, interfere na formaÃÃo de criptas aberrantes na mucosa cÃlica induzida por azoximetano (AOM), em ratos. Foram usados 36 ratos Wistar, machos, com peso mÃdio inicial de 180g a 250g e 8 semanas de idade. Foram distribuÃdos em 04 grupos com 09 animais cada: GI- Grupo com ratos submetidos à DH e nÃo expostos ao AOM, GII- Grupo com ratos submetidos à dieta padrÃo (DP) e nÃo expostos ao AOM, GIII- Grupo com ratos submetidos à DH e expostos ao AOM, GIV- Grupo com ratos submetidos à DP e expostos ao AOM. Utilizou-se, a partir da 8 semana, nos grupos I e III uma dieta hipercalÃrica (4.250cal/kg), rica em gordura poliinsaturada, relaÃÃo &#969;-6: &#969;-3 = 3:1, acrescida de fibras, minerais e vitaminas. Os grupos II e IV receberam uma dieta padrÃo (3.000cal/kg). Na 16 semana, GIII e GIV receberam injeÃÃo de AOM 15mg/kg, intraperitoneal (IP), 01 vez por semana, por 02 semanas, enquanto GI e GII receberam soluÃÃo salina a 0,9%. Foram mortos na 15 semana apÃs a induÃÃo com carcinÃgeno ou administraÃÃo IP de soluÃÃo estÃril. Avaliaram-se os animais quanto ao peso, alteraÃÃo clÃnica, presenÃa de adenomas, FCA e o nÃmero de criptas por foco (multiplicidade) de acordo com a localizaÃÃo cÃlica (proximal, medial e distal). Os resultados foram submetidos aos testes de anÃlise de variÃncia e estabelecido o nÃvel de 5% (p < 0,05) para a rejeiÃÃo da hipÃtese de nulidade. Verificou-se que a dieta hipercalÃrica hiperlÃpidica promoveu um incremento no peso no grupo III, quando comparado ao grupo IV e nÃo apresentou aumento significante no nÃmero total de FCA nos segmentos mÃdio (p = 0,985) e distal (p = 0,854). Analisando ambos os grupos em relaÃÃo à multiplicidade de FCA, nÃo houve predominÃncia da presenÃa de 01 a 04 criptas nos segmentos mÃdio (p = 0,499) e distal (p = 0,244), como tambÃm, de 05 ou mais criptas nos segmentos mÃdio (p = 0,371) e distal (p = 0,820). Verificando a presenÃa do nÃmero total de criptas por foco em toda a mucosa cÃlica, o teste do qui-quadrado mostrou que o grupo IV apresenta, em proporÃÃo, um maior nÃmero de focos com 05 ou mais criptas do que o grupo III (P= 0,043). Conclui-se que a dieta usada aumenta o peso corporal, porÃm nÃo interfere na quantidade de FCA, contudo reduz o aparecimento de criptas aberrantes, quando &#8805; 5 criptas por foco, no colo de ratos Wistar, induzido por azoximetano. / Colorectal cancer is the fifth most common type of cancer in Brazil and the incidence is growing in developed countries. The earliest preneoplastic lesion presenting dysplasia is aberrant crypt foci (ACF), a precursor of colorectal adenoma and cancer in humans. Knowledge of ACF formation is crucial to understanding the mechanisms involved in colorectal cancer and their inhibition. The objective of this study was to determine whether a hypercaloric, hyperlipidic diet (HCD) affects azoxymethane (AOM)-induced ACF formation in rat colonic mucosa. Thirty-six 8-week old male Wistar rats weighing 180-250g were distributed into 4 groups of 9 animals each: Group I: HCD without AOM; Group II: normocaloric diet (NCD) without AOM; Group III: HCD and AOM; Group IV: NCD and AOM. From the eighth week onwards the animals in Groups I and III were fed HCD (4,250 cal/kg; rich in polyunsaturated fat; ratio &#969;6:&#969;3=3:1, with addition of fiber, minerals and vitamins). The animals in Groups II and IV were fed NCD (3,000 cal/kg). At 16 weeks, the animals in Groups III and IV were injected i.p. with 15 mg/kg AOM once a week for 2 weeks, while the animals in Groups I and II received 0.9% physiological saline. At 15 weeks after AOM or saline administration, the animals were euthanized and their weight, clinical changes, adenomas, ACF and number of crypts per focus (multiplicity) according to colon section (proximal, middle or distal) were registered. The findings were submitted to variance analysis and the level of statistical significance was set at 5% (p<0.05). HCD was found to promote weight increase in Group III compared to Group IV. No significant increase in the total number of ACF was observed for the middle and distal segments (p=0.985 and p=0.854, respectively). The multiplicity of foci with 1-4 aberrant crypts was similar for the middle and distal segments (p=0.499 and p=0.244, respectively). The corresponding figures for foci with &#8805;5 aberrant crypts were p=0.371 and p=0.820. The total number of ACF in the colonic mucosa differed significantly between Group IV and Group III (&#967;2 = 4.091; p=0.043). It may thus be concluded that HCD promotes weight increase and, while not affecting the total number of ACF, reduces the proportion of foci with &#8805;5 aberrant crypts, thereby indirectly preventing the emergence of preneoplastic lesions in rat colonic mucosa.

Devant les processus de décomposition, les sociétés humaines réagissent en pratiquant interventions culturelles de 'thanato-métamorphose' sur les cadavres, comme la momification. En Sicile nous trouvons une pratique de momification toute originelle (XVIe ÷ XIXe siècles), pratiquée par les moines des congrégations religieuses, qui se développe selon une série de variations locales. Elle est le fruit d’une longue et non définitive expérimentation, consistant dans une méthode empirique de dessiccation des dépouilles mortelles. Le procédé de conservation se déroulait dans les chambres souterraines annexées aux églises, pourvues des égouttoirs.  La momification reflétait des fonctions et idéologies précises, vivement lié aux possibilités économiques des individus, nécessaires pour maintenir le status économique et social d’appartenance. La lente disparition de la pratique de momification des corps remonte au l’édit de Saint-Cloud du 1804, qui marque l’interdiction législative d’inhumation des cadavres dans les églises et l’apparition des premiers cimetières extra moenia. Cependant, beaucoup d'éléments de la séculaire pratique de la momification survécurent. Les données recueillies nous poussent à penser que la momification fût une pratique bien enracinée dans le monde sicilien, et qu’après et malgré les décrets législatifs du 1804, elle ait 'survécu', en influençant l'enterrement et la relation avec la Mort jusqu'à nos jours. / Having to do with the processes of decomposition, the human societies react by practicing cultural interventions of 'thanato-metamorphosis' on bodies, as the mummification. In Sicily we find a practice of mummification really original (XVI th ÷ XIX th centuries), practiced by the monks of the religious congregations, which develops according to a series of local variations. This practice is the fruit of long and not definitive experimentation, consisting in an empirical method of dehydration of human remains. The process of conservation of bodies took place in the subterranean rooms annexed to churches, provided with colanders. The mummification reflected particulars functions and ideologies, deeply tied to the economic possibilities of the individuals, necessaries to maintain the economic and social status of belonging. The slow disappearance of the mummification’s practice goes up to the edict of Saint-Cloud of the 1804, which marks the legislative interdiction of burial’s bodies in churches and the appearance of first cemeteries extra moenia. However, many elements of secular practice of mummification have survived. By the informations gathered on mummification’s practice we think that the practice was well rooted in the sicilian world, after the legislative decree of the 1804, and that it has survived, by influencing to bury and the relation with the Death until our days.

The Wnt signaling pathway represents the principal evolutionarily conserved signaling cascade found in all multicellular organisms. It plays a key role not only in many processes during embryogenesis, but also in maintaining tissue homeostasis and regeneration. By contrast, mutations in genes encoding components of the pathway often result in increased activation of Wnt signaling and underlie onset of many human diseases, particularly cancer. The canonical Wnt signaling pathway is essential for proliferation and maintenance of the pluripotent state of intestinal stem cells and thus for homeostatic renewal of the intestinal epithelium. However, aberrant (hyper)activation of the Wnt signaling pathway is the initial step in development of intestinal neoplasia. Understanding the causes and identifying the consequences of the Wnt signaling hyperactivation is crucial for deciphering mechanisms leading to malignant transformation. Although the canonical Wnt signaling pathway has been the subject of scientific studies for several decades, all regulatory mechanisms and consequences of its hyperactivation have not been completely elucidated yet. During my PhD studies, I focused on understanding function(s) of some components and target genes of this signaling cascade. In this theses, results of my first...

<p>This dissertation explains why behavioral genetic research can be better informed by using characteristics in the human iris as biomarkers for personality, and is divided into five parts. Part I gives an introduction to the classical twin method and an overview of the findings that have led most developmental researchers to recognize that the normal variation of personality depends on a complex interplay between genetic and environmental factors. Part II highlights empirical findings that during the last twenty years have gradually moved genetic and environmental theory and research to evolve toward one another, and also presents the theory of genetics and experience that currently is used to explain how the interplay between genes and the environment works. Part III explains why, from a developmental perspective, it is of interest to identify candidate genes for personality, and gives a brief overview of genes that have been associated with personality. Problems associated with genetic research on the molecular level and how these apply to personality are also highlighted. Part IV examines molecular research on the iris and the brain, which suggests that genes expressed in the iris could be associated with personality, and explains how the use of iris characteristics can increase power to test candidate genes for personality by taking advantage of the self-organizing properties of the nervous system. The empirical foundation for the questions posed in this dissertation and also the empirical results are presented here. Part V discusses the associations found between iris characteristics and personality, and exemplifies how iris characteristics can be used within the theoretical frameworks presented in parts I, II, III and IV. In other words, Part V explains how iris characteristics – in addition to identify as well as test candidate genes for personality – can be used to investigate how people’s experiences in themselves are influenced by genetic factors.</p>

This dissertation explains why behavioral genetic research can be better informed by using characteristics in the human iris as biomarkers for personality, and is divided into five parts. Part I gives an introduction to the classical twin method and an overview of the findings that have led most developmental researchers to recognize that the normal variation of personality depends on a complex interplay between genetic and environmental factors. Part II highlights empirical findings that during the last twenty years have gradually moved genetic and environmental theory and research to evolve toward one another, and also presents the theory of genetics and experience that currently is used to explain how the interplay between genes and the environment works. Part III explains why, from a developmental perspective, it is of interest to identify candidate genes for personality, and gives a brief overview of genes that have been associated with personality. Problems associated with genetic research on the molecular level and how these apply to personality are also highlighted. Part IV examines molecular research on the iris and the brain, which suggests that genes expressed in the iris could be associated with personality, and explains how the use of iris characteristics can increase power to test candidate genes for personality by taking advantage of the self-organizing properties of the nervous system. The empirical foundation for the questions posed in this dissertation and also the empirical results are presented here. Part V discusses the associations found between iris characteristics and personality, and exemplifies how iris characteristics can be used within the theoretical frameworks presented in parts I, II, III and IV. In other words, Part V explains how iris characteristics – in addition to identify as well as test candidate genes for personality – can be used to investigate how people’s experiences in themselves are influenced by genetic factors.

The goal of this long-term study was to better understand the reproductive biology of the female bottlenose dolphin (Tursiops truncatus) and provide a hypothesis for how dolphins may communicate reproductive readiness to one another. Utilizing conditioned dolphins in aquaria, this dissertation examined several previously unknown aspects of dolphin reproduction, including ovarian follicular dynamics during the luteinizing hormone surge, urinary prolactin levels, estrus behavior, vaginal fluid arboriform arrangement, in-situ vaginal and cervical anatomy during estrus, reversed-phase high-performance liquid chromatography (RP-HPLC) of urine samples to identify proteins and peptides that may be used in chemical communication, and a review and anatomical analysis of dolphin vibrassal crypts. The diffusely seasonal dolphin estrous cycle is not controlled by photoperiod and has a 10-day follicular and 20-day luteal phase. A brief ovulatory LH surge is followed by ovulation within 48 hours. An ethogram of 20 reproductive behaviors was developed, and all occurrences of reproductive behavior were analyzed during conceptive estrous cycles. A novel form of standing heat estrus, termed immobility, was observed, and estrus dolphins displayed genital nuzzling, active and passive mounting with other females, and an increase of standing heat intensity as LH levels rose. Prolactin plays a role in pregnancy maintenance, mammary development, allo-mothering behavior, lactation, and lactational anestrus. Dolphins are similar to sows where weaning causes a return to estrus, and in the boar effect, where days to ovulation are shortened in the presence of a mature male. Dolphin vaginal fluid showed crystallization arrangements with large open mesh patterns, conducive to sperm transport, during the estrogenic follicular phase, and closed mesh during the luteal phase. RP-HPLC analysis revealed that urine contained large amounts of peptides and proteins with peaks that change throughout the estrous cycle and with changes in social grouping. Remnant vibrissae from dolphin follicular crypts were sectioned, and it was hypothesized that trigeminal nerve endings could act similarly to those found in the nasal mucosa of terrestrial species and respond to chemical stimuli. This study provides new data to better understand the reproductive biology of a holaquatic mammal.

Estudos epidemiológicos vêm demonstrando que quantidades apropriadas de atividade física regular estão associadas a significativa redução do risco para o desenvolvimento de câncer de cólon em até 40% entre os indivíduos mais fisicamente ativos. Por outro lado, tem sido observado que o exercício físico exaustivo aumenta a produção sistêmica de radicais livres, com concomitante aumento dos danos oxidativos ao DNA, além de deprimir a função imune global, eventos relacionados ao aumento do risco para o desenvolvimento de câncer. Relativamente, poucos estudos experimentais exploram essas relações, principalmente no que concerne ao exercício exaustivo e o câncer. A taxa de proliferação celular epitelial, os focos de criptas aberrantes (FCAs) e as criptas com acúmulo de beta-catenina (CABC) têm sido marcadores biológicos (biomarcadores) usados para a identificação precoce de fatores que poderiam influenciar a carcinogênese colônica em ratos. Através da aplicação do carcinógeno químico 1,2dimetilhidrazina (DMH), logo após os protocolos de exercício, foram estudados quatro grupos principais de ratos previamente sedentários (grupo-controle, e três grupos submetidos, respectivamente, ao treinamento crônico de natação, à natação até a exaustão, e à natação até a exaustão após treinamento crônico), sendo sacrificados quinze dias após a injeção da DMH. Após análise histológica e imunohistoquímica, os biomarcadores estudados mostraram resultados coerentes nas diferentes situações experimentais aferidas. Foi observada uma diminuição estatisticamente significante da resposta hiperproliferativa, do número de FCAs e de CABC no grupo que realizou o treinamento crônico, enquanto o grupo submetido ao exercício exaustivo apresentou aumento estatisticamente significante dos parâmetros citados, quando comparados ao grupo-controle. No grupo submetido à associação dos dois protocolos de exercício, quando comparado ao grupo-controle, não houve alterações significantes nos biomarcadores de transformação neoplásica estudados. Nesse estudo experimental, o treinamento físico crônico teve efeito protetor contra o desenvolvimento dos biomarcadores precoces de transformação neoplásica do cólon, enquanto o exercício físico exaustivo aumentou a prevalência destes em ratos sedentários. O treinamento físico crônico, quando associado ao exercício físico exaustivo, não alterou a prevalência dos biomarcadores estudados. Desse achado, acrescido do que se pode encontrar na literatura científica atual, levanta-se a hipótese de que, de maneira similar à relação entre exercício físico e infecções, também o exercício poderia ou proteger contra o desenvolvimento, ou aumentar o risco para o câncer, dependendo do tipo, intensidade e duração da atividade desenvolvida. / Ephitelial cell proliferation, aberrant crypt foci (ACF) and â-catenin-accumulated crypts (BCAC) have been used for early detection of factors that influence colorectal carcinogenesis in rats. It has been observed that moderate and regular physical activity may prevent colon cancer up to 40% in humans. However, exhaustive exercise increases free radical DNA oxidative damage and depresses immune function, events also related to the increased risk for cancer development. Fifteen days after either a single exhaustive swimming bout or a swimming physical training for 8 weeks, or both, in untrained rats treated with a colon carcinogen, we observed a statistically significant decreased number of those biomarkers in rats under training protocol, and a statistically significant increased number of them in rats under exhaustive protocol, when compared to the non-exercised group. For the rats under exhaustive protocol after being trained, data was not evident. Thus, we concluded that training protected against the biomakers development and exhaustive exercise improved colorectal carcinogenesis biomarkers development in sedentary rats. From our finding and literature data, we hypothesize that, similarly to the suggested relationship between exercise and infections, exercise could be protective against cancer or it could increase the risk for this disease depending on its type, dose and duration.

Estudos epidemiológicos vêm demonstrando que quantidades apropriadas de atividade física regular estão associadas a significativa redução do risco para o desenvolvimento de câncer de cólon em até 40% entre os indivíduos mais fisicamente ativos. Por outro lado, tem sido observado que o exercício físico exaustivo aumenta a produção sistêmica de radicais livres, com concomitante aumento dos danos oxidativos ao DNA, além de deprimir a função imune global, eventos relacionados ao aumento do risco para o desenvolvimento de câncer. Relativamente, poucos estudos experimentais exploram essas relações, principalmente no que concerne ao exercício exaustivo e o câncer. A taxa de proliferação celular epitelial, os focos de criptas aberrantes (FCAs) e as criptas com acúmulo de beta-catenina (CABC) têm sido marcadores biológicos (biomarcadores) usados para a identificação precoce de fatores que poderiam influenciar a carcinogênese colônica em ratos. Através da aplicação do carcinógeno químico 1,2dimetilhidrazina (DMH), logo após os protocolos de exercício, foram estudados quatro grupos principais de ratos previamente sedentários (grupo-controle, e três grupos submetidos, respectivamente, ao treinamento crônico de natação, à natação até a exaustão, e à natação até a exaustão após treinamento crônico), sendo sacrificados quinze dias após a injeção da DMH. Após análise histológica e imunohistoquímica, os biomarcadores estudados mostraram resultados coerentes nas diferentes situações experimentais aferidas. Foi observada uma diminuição estatisticamente significante da resposta hiperproliferativa, do número de FCAs e de CABC no grupo que realizou o treinamento crônico, enquanto o grupo submetido ao exercício exaustivo apresentou aumento estatisticamente significante dos parâmetros citados, quando comparados ao grupo-controle. No grupo submetido à associação dos dois protocolos de exercício, quando comparado ao grupo-controle, não houve alterações significantes nos biomarcadores de transformação neoplásica estudados. Nesse estudo experimental, o treinamento físico crônico teve efeito protetor contra o desenvolvimento dos biomarcadores precoces de transformação neoplásica do cólon, enquanto o exercício físico exaustivo aumentou a prevalência destes em ratos sedentários. O treinamento físico crônico, quando associado ao exercício físico exaustivo, não alterou a prevalência dos biomarcadores estudados. Desse achado, acrescido do que se pode encontrar na literatura científica atual, levanta-se a hipótese de que, de maneira similar à relação entre exercício físico e infecções, também o exercício poderia ou proteger contra o desenvolvimento, ou aumentar o risco para o câncer, dependendo do tipo, intensidade e duração da atividade desenvolvida. / Ephitelial cell proliferation, aberrant crypt foci (ACF) and â-catenin-accumulated crypts (BCAC) have been used for early detection of factors that influence colorectal carcinogenesis in rats. It has been observed that moderate and regular physical activity may prevent colon cancer up to 40% in humans. However, exhaustive exercise increases free radical DNA oxidative damage and depresses immune function, events also related to the increased risk for cancer development. Fifteen days after either a single exhaustive swimming bout or a swimming physical training for 8 weeks, or both, in untrained rats treated with a colon carcinogen, we observed a statistically significant decreased number of those biomarkers in rats under training protocol, and a statistically significant increased number of them in rats under exhaustive protocol, when compared to the non-exercised group. For the rats under exhaustive protocol after being trained, data was not evident. Thus, we concluded that training protected against the biomakers development and exhaustive exercise improved colorectal carcinogenesis biomarkers development in sedentary rats. From our finding and literature data, we hypothesize that, similarly to the suggested relationship between exercise and infections, exercise could be protective against cancer or it could increase the risk for this disease depending on its type, dose and duration.