Climate has a selective influence on nasal cavity morphology. Due to the constraints of cranial integration, naturally selected changes in one structure necessitate changes in others in order to maintain structural and functional cohesion. The relationships between climate and skull/nasal cavity morphology have been explored, but the integrative role of nasal variability within the skull as a whole has not. This thesis presents two hypotheses: 1) patterns of craniofacial integration observed in 2D can be reproduced using 3D geometric morphometric techniques; 2) the nasal cavity exhibits a higher level of covariation with the lateral cranial base than with other parts of the skull, since differences in nasal morphology and basicranial breadth have both been linked to climatic variables. The results support the former hypothesis, but not the latter; covariation observed between the nasal cavity and other cranial modules may suggest that these relationships are characterized by a unique integrative relationship. / February 2016

A ruptura total ou parcial do ligamento cruzado cranial (LCCr), é considerada uma das principais causas de instabilidade no cão e está entre as mais freqüentes afecções ortopédicas no cão. A ruptura do ligamento cruzado cranial (RLCCr) implica em tratamento cirúrgico por artroscopia ou artrotomia e se faz necessária a retirada dos seus resquícios e a sua substituição. Trinta e oito amostras de LCCr rompidos de animais submetidos ao tratamento cirúrgico para RLCCr e 13 amostras de LCCr íntegro de cadáveres de cães que tenham vindo a óbito por diferentes causas e sem histórico de doença articular foram coletadas para a realização de um estudo morfométrico, ultra-estrutural e imuno-histoquímico das células e componentes da matriz extracelular presentes no LCCr desses cães. Os cortes histológicos foram corados pela Hematoxilina-Eosina para análise histopatológica, Picrossirius-Hematoxilina para análise do colágeno, Resorcina- Fucsina para estudo das fibras do sistema elástico e Alcian-Blue-PAS para proteoglicanas. Os resultados sugeriram que houve diferença significativa entre os LCCr rompidos do grupo dos Labradores e as amostras íntegras do grupo controle no que diz respeito às alterações celulares. Em relação ao estudo de fibras colágenas a área ocupada foi significativamente maior no grupo controle. Não houve diferença significativa entre os grupos em relação às fibras do sistema elástico, entretanto, houve correlação entre a densidade linear destas fibras com a idade dos animais. Também foi possível estabelecer uma correlação entre peso e idade e, entre peso e tempo de evolução da doença articular. No estudo imuno-histoquímico para α-actina de músculo liso e Caspase 3, o grupo cirúrgico apresentou maior número de marcações positivas que o grupo controle. / Total or partial rupture of the cranial cruciate ligament (CCL) is one of the main causes of instability on dogs and is one of the most frequent orthopedic conditions of the dog. The rupture of CCL demands surgical procedure by arthroscopy or arthrotomy and the extraction and replacement of its remaining fragments is needed. Thirty-eight samples of ruptured CCL, collected during the surgical time and thirteen samples of intact CCL collected from cadavers of dogs without articular disease history were examined in this study. Morphometric, ultrastructural and immunohystochemical techniques were realized to study cells and extracellular matrix of CCL samples. The tissue sections were stained by Hematoxilyn-Eosin to histopathological study, Picrosirius-Hematoxilyn to collagen study, Resorcin-Fucsin to elastic fibers study and Alcian Blue-PAS to proteoglicans study. The results suggest that there were signifcant differences between the ligaments of the Labrador retrievers and the intact ligaments of the control group regarding the cellular changes. The control group had a significant larger area occupied by collagen fibers than the other groups. There is no statistical difference on elastic fibers among the groups. However the linear density of elastic system fibers could be correlationated with age of dogs. There was a correlation between weight and age, and betwwen weight and time of development of articular disease. Immunohistochemical study showed more positive cells to α-smooth muscle actin and caspase-3 in the ruptured CCL than the control group.

A ruptura total ou parcial do ligamento cruzado cranial (LCCr), é considerada uma das principais causas de instabilidade no cão e está entre as mais freqüentes afecções ortopédicas no cão. A ruptura do ligamento cruzado cranial (RLCCr) implica em tratamento cirúrgico por artroscopia ou artrotomia e se faz necessária a retirada dos seus resquícios e a sua substituição. Trinta e oito amostras de LCCr rompidos de animais submetidos ao tratamento cirúrgico para RLCCr e 13 amostras de LCCr íntegro de cadáveres de cães que tenham vindo a óbito por diferentes causas e sem histórico de doença articular foram coletadas para a realização de um estudo morfométrico, ultra-estrutural e imuno-histoquímico das células e componentes da matriz extracelular presentes no LCCr desses cães. Os cortes histológicos foram corados pela Hematoxilina-Eosina para análise histopatológica, Picrossirius-Hematoxilina para análise do colágeno, Resorcina- Fucsina para estudo das fibras do sistema elástico e Alcian-Blue-PAS para proteoglicanas. Os resultados sugeriram que houve diferença significativa entre os LCCr rompidos do grupo dos Labradores e as amostras íntegras do grupo controle no que diz respeito às alterações celulares. Em relação ao estudo de fibras colágenas a área ocupada foi significativamente maior no grupo controle. Não houve diferença significativa entre os grupos em relação às fibras do sistema elástico, entretanto, houve correlação entre a densidade linear destas fibras com a idade dos animais. Também foi possível estabelecer uma correlação entre peso e idade e, entre peso e tempo de evolução da doença articular. No estudo imuno-histoquímico para α-actina de músculo liso e Caspase 3, o grupo cirúrgico apresentou maior número de marcações positivas que o grupo controle. / Total or partial rupture of the cranial cruciate ligament (CCL) is one of the main causes of instability on dogs and is one of the most frequent orthopedic conditions of the dog. The rupture of CCL demands surgical procedure by arthroscopy or arthrotomy and the extraction and replacement of its remaining fragments is needed. Thirty-eight samples of ruptured CCL, collected during the surgical time and thirteen samples of intact CCL collected from cadavers of dogs without articular disease history were examined in this study. Morphometric, ultrastructural and immunohystochemical techniques were realized to study cells and extracellular matrix of CCL samples. The tissue sections were stained by Hematoxilyn-Eosin to histopathological study, Picrosirius-Hematoxilyn to collagen study, Resorcin-Fucsin to elastic fibers study and Alcian Blue-PAS to proteoglicans study. The results suggest that there were signifcant differences between the ligaments of the Labrador retrievers and the intact ligaments of the control group regarding the cellular changes. The control group had a significant larger area occupied by collagen fibers than the other groups. There is no statistical difference on elastic fibers among the groups. However the linear density of elastic system fibers could be correlationated with age of dogs. There was a correlation between weight and age, and betwwen weight and time of development of articular disease. Immunohistochemical study showed more positive cells to α-smooth muscle actin and caspase-3 in the ruptured CCL than the control group.

In skeletal studies of prehistoric populations of Chile’s semiarid north, it is common practice for physical anthropologists to visually categorize crania as dolichophallic and brachycephalic which are then attributed to cultures or time periods based on the observed shape. The validity of this classification is still debated and poses several questions regarding the prehistory of Chile. The goal of this study is to investigate the craniofacial variation in populations representing the Archaic period and Intermediate-Late periods of Chile’s semiarid north using morphometric analysis. The samples comprise two collections from the Museo Arqueologico de La Serena in La Serena, Chile. The Archaic period dates from 10,000 BC to 300 AC. The Intermediate-Late period dates from 900 AC to 1500 AC. The Archaic period included 87 crania, while the Intermediate-Late period included 78 crania. Cranial vault modification was practiced in all prehistoric populations, and modified individuals comprise ~4.6% of the Archaic period sample and ~74.4% of the Intermediate-Late period sample. Individuals observed to be dolichocephalic are associated with the Archaic period, while brachycephalic individuals are associated with the Intermediate-Late period. Previous studies have shown that individuals with intentional cranial modification, annular and tabular, exhibit predictable changes in the craniofacial complex due to compensatory growth and shape changes related to peripheral structures of the cranial vault. A form of tabular modification is seen in both periods included in this sample, with the Intermediate-Late period sample being dominated by this modification. All craniometric landmarks were recorded using a Microscribe™ 3D digitizer, with exclusion of mandibular landmarks. MorphoJ was utilized to analyze the geometric morphometric data. Coordinates using the Microscribe were recorded in order to investigate the differences in shape of the craniofacial complex between the two samples. Two separate analyses were performed, one with all landmarks recorded and one excluding landmarks prosthion, alveolon, ectomolare and zygion. The results of both Canonical Variate analyses and associated Mahalanobis Distance values (2.699 and 2.9316) indicates statistically significant differences (p<0.001) between the two samples. It is also evident that shape changes along CV1, increases in minimum frontal breadth, upper facial breadth, and nasal height, correspond with characteristics associated with brachycephalism and tabular cranial vault modification. The large range of variation of the Intermediate-Late period sample is speculated to be a result of multiple small populations moving toward the coast possibly due to a change in climate. These small populations exhibited various morphologies which were influenced by nonrandom environmental factors. The Mahalanobis distances of the different cultural groups also indicate statistically significant differences. This method has the potential to be used in conjunction with others to identify cultural context and significance of remains in archaeological contexts in Chile. In the event of repatriation acts this method could also be used to attribute individuals to corresponding cultures and be donated to the appropriate community or facility.

Objective: To evaluate the relative position of the femur and tibia in cranial cruciate ligament (CCL) intact stifles, CCL deficient stifles, and stifles following a novel extracapsular procedure (lateral extracapsular suture system or LESSa) under load at specific joint angles. Study Design: In vitro biomechanical study. Methods: Twenty pelvic limbs from 11 dogs were used to evaluate the relative position of the femur and tibia between 3 stifle conditions (CCL intact, CCL deficient, and LESSa treated) at a load of 30 % and stifle angles of 125", 135", and 145" using electromagnetic tracking sensors. Results: Cranial cruciate ligament deficient stifles had significantly greater (p <0.0001) cranial displacement and internal rotation of the tibia relative to the femur than CCL intact stifles or LESSa treated stifles at all stifle angles. Cranial displacement of the tibia relative to the femur for CCL intact and LESSa treated were not significantly different from one another at stifle angles of 125", but were significantly different at stifle angles of 135" (p = 0.0182) and 145" (p = 0.0012). There was no significant difference in internal rotation of the tibia relative to the femur between CCL intact and LESSa treated stifles at any of the stifle angles. Conclusion: LESSa effectively decreases cranial tibial displacement and eliminates internal rotation of the tibia relative / Master of Science

Canine cruciate ligament (CCL) rupture is a common veterinary orthopaedic problem, and has been associated with problems at the ipsilateral hip joint. However, the relationship between stifle and hip dysfunction has not been fully investigated. The purpose of this study was to establish whether CCL pathology is associated with a limitation in hip extension range large enough to affect gait. In a prospective, crosssectional study, passive and active hip extension range was determined in normal dogs as well as CCL deficient dogs. There was a significant reduction in ipsilateral passive hip extension range in the CCL deficient dogs (18.63º+/-7.57).There was a significant increase in hip extension range of the unaffected leg during gait compared to the normal group (7.03º+/-8.41). It was therefore concluded that canine CCL pathology directly affects hip extension range to a degree sufficient to affect normal gait.

PhD, Faculty of Health Sciences, University of the Witwatersrand / While ethanol is recognised beyond doubt as a teratogen to the unborn fetus, research nevertheless continues in order to understand its mode of action and its effects at the cellular level. The present study aimed to investigate the effect of an acute dose of ethanol on cranial morphology and morphometry in mouse fetuses, as well as on the morphology, migration and the expression of cell migration related genes in cultured chick cranial neural crest cells (cNCCs). Thirteen pregnant C57/BL mice were orally administered with 0.03ml/g of 25% (v/v) ethanol daily on gestational days (GD) 6, 7 and 8. Ten control animals received an identical dose of saline. On GD 18, all mice dams were killed and their fetuses were removed. Fetal morphological observations and crown-rump lengths were evaluated as were mean litter size, survival rate, birth weight and cranial dimensions. Cranial neural crest cells (cNCCs) were cultured from Potchefstroom koek koek stages 8-10 (HH) chick embryo neural tubes either in culture medium (DMEM) to which 0.2%, 0.3% and 0.4% ethanol (v/v) respectively, was added (treated) or in DMEM only (controls). Whole-mount HNK-1 immunocytochemistry was performed on treated and control chick embryos, as was an assay for caspase-dependent apoptosis. Photographs were taken of the cultures and the distance which the neural crest cells migrated from the neural tube at 24 and 48 hrs post-culture was measured. 24-hr time-lapse video microscopy recordings were also made to analyse the migration of the neural crest cells. Rhodamine-phalloidin immunocytochemistry for the actin cytoskeleton and scanning electron microscopy of surface ultrastructure were performed on migrating treated and non-treated cNCCs, as were proliferation assays and quantitative PCR of cNCCs‟ β-actin, Rac 1, Rho B and slug genes. There was a statistically significant increase in fetal reabsorption as well as a significantly reduced fetal survival rate observed in newborn mice fetuses that had been exposed to ethanol in utero compared to control fetuses. Ethanol-exposed mice showed a number of abnormalities, which were not significantly increased over vi controls (p>0.5). Birth weight, crown-rump length and mandibular length were also not significantly different in treated fetuses compared to controls (p>0.5). Treated (0.3%) chick cNCCs migrated over a significantly increased distance at both 24hrs and 48hrs compared to controls (p<0.05) in the axes of migration that were studied. The migratory distances of cNCCs derived from embryonic stage 9 (HH) were markedly affected by treatment with alcohol. The actin cytoskeleton of treated cNCCs showed disorganisation and loss of focal adhesion contacts while Rac 1, Rho B and slug genes were either up-regulated or down-regulated depending on the ethanol dose and duration of treatment. Ethanol promotes significant proliferation in cNCCs and may affect their migration by altering the expression of migration-linked genes and the arrangement of the actin cytoskeleton.

Os padrões de covariância genética entre caracteres, expressos pela matriz de covariância aditiva G, desempenham um papel importante na evolução de morfologias complexas, visto que esta matriz influencia a direção e magnitude da resposta à seleção em uma população. Assumindo-se a estabilidade da matriz G ao longo do tempo, pode-se testar explicitamente hipóteses acerca da influência de processos evolutivos sobre a diversificação. Espera-se que esta matriz influencie os padrões expressos por sua equivalente fenotípica P, devido a contingências funcionais e ontogenéticas na relação entre genótipo e fenótipo, que levam à estruturação de modularidade nesta relação, de modo a otimizar a evolvabilidade. No presente trabalho, investiguei a estrutura da covariância genética no crânio e mandíbula de uma população do roedor sigmodontíneo Calomys expulsus, com o objetivo de estimar a similaridade entre covariâncias fenotípicas e genéticas; também avaliei a influência de padrões de modularidade sobre ambos os níveis de organização da variação morfológica. As matrizes P e G que obtive para o crânio e para a mandíbula se mostraram bastante similares no que diz respeito à sua estrutura de covariação e se relacionam parcialmente às hipótese de modularidade estabelecidas. Os resultados que obtive aqui são bastante similares àqueles obtidos para os mamíferos como um todo, portanto suportando a hipótese de estabilidade no padrão de covariâncias genéticas e fenotípicas na evolução do grupo. / Patterns of genetic covariance between characters (represented by the additive covariance matrix G) play an important role in the evolution of morphological complexes, since they influence the direction and norm of the response to selection in a population. Therefore, the assumption that G-matrices are stable through evolutionary timescales allows evolutionary biologists to infer the influence of evolutionary processes that operate over biological diversification. These matrices are also expected to influence the patterns expressed in their phenotypic counterparts (P-matrix), because of the imposition of multiple developmental and functional contingencies over the genotype/phenotype map, that leads to its modular organization in order to increase evolvability. Here, I have investigated patterns of genetic covariance structure in the skull and mandible of a population of the vesper mouse Calomys expulsus in order to estimate the level of similarity between additive and phenotypic covariances; I have also evaluated the influence of expected patterns of modularity over both levels of morphological variation. For either skull and mandible, I have obtained P- and G-matrices that are strongly similar in their structure; these matrices also support the modularity hypotheses for developmental and functional constrains, akin to the overall results obtained for mammals, thus supporting the hypothesis of stability in genetic and phenotypic covariance structure in mammalian evolution.

Cranial vault thickness (CVT) has been reported at many different osteometric landmarks and features on the vault. Historically, only a few landmarks are used, often bregma, lambda, vertex, and right and left euryon, and frequently comparisons are based only on “thick” versus “thin” to describe the vault overall. What is inherent in this strategy is the use of a few locations to characterize the entire vault. The problem remains that there is little information concerning CVT variation throughout an individual's vault, and the causes of variation within recent Homo sapiens important to investigating thickness variation between species in Homo. This work describes thickness variation over the entire superior vault and compares the sexes, age groups and populations in recent H. sapiens. A proportional grid is applied to the superior vault to measure thickness at 219 sampling points in a geographically diverse sample of recent H. sapiens. Thickness values are analyzed in their two-dimensional spatial relationships to determine patterns of vault thickness. Males were identified to be thicker than females at more lateral locations and along the midsagittal plane, although this finding is not statistically significant. Individuals over the age of 45 years are found to be statistically significantly thicker than individuals younger than 31 years at more lateral locations of the vault. Aboriginal Australians are statistically significantly thicker at more lateral locations of the vault than any other populations, whereas Northern Canada/Greenland individuals were thinner than other populations at these locations. The trend of thicker vaults in the older age group and the Australians is identified across the vault, although is not statistically significant at more locations. Several thickness patterns are identified. The boss thickening pattern is the most common pattern, followed by a midsagittal pattern, a posterior pattern, and an anterior pattern. Some specimens do not demonstrate thickness variation and are coded as undifferentiated. Each pattern is observed alone and in combination with others, signifying that pattern causes are not mutually exclusive. Boss thickening is interpreted as the result of passive bone thickening during normal bone and brain growth during fetal and adolescent development. The midsagittal thickness pattern coincides with inferred strain along the sagittal suture from nuchal muscle engagement during mastication. Previous researchers have proposed adaptive explanations for thickness variation, such as protection from interpersonal violence; the patterns of cranial vault thickness reported here point to normal growth and development of the brain as a driving force, a relationship that could drive thickness variation in other Homo species. Comparing thickness at bregma, and the frontal and parietal eminences for recent H. sapiens and H. erectus, there is no statistical difference between African and Asian H. erectus, and between the on average thicker H. sapiens populations and H. erectus, based on published data. Future work will investigate the presence or absence of thickness patterns in these fossil species.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 137-153).