Sinonasal and dental diseases can be a serious disorder in horses due to the persistence of the former and the common extension of the latter to the supporting bones of the skull. The diagnosis of equine sinonasal and dental disease can be challenging due to the complexity of these and adjacent anatomical structures, and therefore the use of advanced imaging, including computed tomography (CT) has greatly increased recently. A major aim of this study was to improve the morphological characterization of the sinuses and cheek teeth in normal horses of different ages. These studies defined the volumes of the 7 different sinus compartments; showed that the volume of the different compartments increase with age; that in contrast to accepted findings, the Triadan 09 alveoli is located in the caudal maxillary sinus (CMS) in 13% of the youngest group and the Triadan 10 alveoli is fully within the rostral maxillary sinus (RMS) in 53% of cases. The infraorbital canal was found to be susceptible to apical infection-related damage in horses < 2 years of age (< 2 y.o.) due to the intimate relationship of this canal and the medial aspect of the maxillary cheek teeth alveoli. The mean positions of the clinical crowns and apices of the maxillary Triadan 11s were 2.48 cm (adjusted 5.2% of head height) and 2.83 cm (adjusted 6.2% of head height) more rostral, respectively in horses >16 y.o. compared to horses < 6 y.o., consistent with rostral dental drift. Measurements of dental drift could provide further objective radiographic guidelines on ageing horses by dental imaging and also help our understanding of the aetiopathogenesis of cheek teeth diastemata. This study also found that the reserve crown length decreased from a mean of 4.7 cm (adjusted 19.7% of head height) in the youngest (< 6y.o.) group of horses to a mean of 2.9 cm (adjusted 10.5% of head height) in the oldest group (>15y.o.), with the 06s and 09s having the shortest reserve crowns. These data are useful reference information for clinicians and radiologists in the diagnosis and treatment of equine sinonasal and dental disease. Morphological characterization of the ventral and dorsal conchal bullae in horses of different age using CT described the age-related difference in sizes of these structures (smaller in younger horses). In the ventral conchal bulla, this reduction in volume was probably related to protrusion of the large dental alveoli in young horses into the nasal cavity and bulla. Bullae linear measurements and volumes were also associated with head size. The anatomical position of both bullae was associated with specific maxillary cheek teeth, thus increasing the diagnostic value of conventional radiography in the investigation of bulla disease and providing landmarks for the surgical treatment of this disorder. Skull shape analyzed with the use of Procrustes statistical analysis showed landmark variability between different age groups and in particular, high landmark variability between young (< 5y.o.) and old (>16y.o.) horses and less landmark variability between adult (6-15y.o.) and old horses. Future studies could investigate changes in the equine skull in relation to genotype to characterize breed-related diseases affecting teeth and sinonasal compartments. In the second part of the study, 32 infected maxillary cheek teeth extracted from clinical cases were evaluated grossly and histologically and these pathological results were compared to the pre-extraction radiographic and CT imaging findings. This study showed a high sensitivity (97%) of CT in detecting changes in teeth affected by apical infection. In the third part of the study, 30 cheek teeth assessed as being abnormal based on oral, radiographic and CT examinations were extracted along with their alveoli from 27 cadaver heads. Gross and histological examination findings from these teeth and alveoli were compared to the pre-extraction imaging findings, again showed high sensitivity (96.4%) of CT in diagnosing cheek teeth apical infection. Additionally, CT showed a high correlation with histology in detecting dental infection related alveolar bone changes including alveolar bone lysis, sclerosis and bone thickening. This aspect of the study was also the second largest pathological study of equine apical infection published to date and thus has also improved our understanding of the pathogenesis of this disorder. In conclusion, CT was shown to be an excellent imaging modality for improving the morphological characterization of the sinuses and teeth in normal horses of different ages, and thus also improving the value of this modality in diagnosis and treatment of disease affecting sinonasal and dental structures. This study also objectively showed the high sensitivity of CT in detecting cheek teeth apical infection in horses as compared to radiography, including by assessment of alveolar bone changes. Overall, the results of this project improve morphological knowledge of the equine skull and teeth and will have direct clinical benefits by improving the diagnosis and thus the treatment of equine sinonasal and dental disease.

Craniostenose é o fechamento precoce de uma ou mais suturas cranianas, levando ao redirecionamento do crescimento craniofacial e à deformidade do crânio. Estudos têm pesquisado o impacto da fusão da sutura sagital na base do crânio, focalizando a morfologia da base do crânio na presença de craniostenose sagital isolada (escafocefalia), enquanto outros têm avaliado o crescimento da base do crânio, antes e após a cirurgia. Este estudo teve como objetivo realizar as medidas antropométricas da base do crânio em crianças com escafocefalia, avaliar a influência da correção cirúrgica no remodelamento da base do crânio e nas medidas antropométricas. Foram operadas 21 crianças com diagnóstico clínico e radiológico de escafocefalia, entre abril de 2007 e outubro de 2008, sendo realizadas medidas antropométricas na base do crânio, antes e após 1 ano do tratamento cirúrgico. As medidas foram o índice craniano (IC), distância entre a crista galli e o tubérculo selar (CG-TS), distância entre a crista galli e o meato acústico interno (CG-MAI), distância entre os forames ovais (FO-FO), distância entre os meatos Acústicos internos (MAI-MAI), o ângulo da base do crânio Â1) e o ângulo entre o násio, centro selar e básio (Â2). Houve normalização do IC em todas as crianças, confirmando um remodelamento craniano adequado. A medida CG-TS avaliou a base do crânio anterior, com crescimento proporcional de 12,5%. O crescimento médio-lateral foi observado pelo aumento das medidas FO-FO de 8,5% e MAI-MAI de 9,5%. A medida CG-MAI teve um crescimento de 7,2%. Não houve diferença estatística nos ângulos basais Â1 e Â2 analisados. O tratamento cirúrgico da escafocefalia levou ao remodelamento da base do crânio, confirmado pelas mudanças das medidas antropométricas realizadas antes e após 1 ano da cirurgia / Craniosynostosis is defined as the premature closure of one or more sutures, leading to redirection of the craniofacial growth and deformity of the skull. Studies have examined the impact of fusion of the sagittal suture in the skull base, focusing on the morphology of the skull base in the presence of isolated sagittal craniosynostosis (scaphocephaly), while others have evaluated the growth of the skull base before and after surgery. This study aims to perform the anthropometric measures of the skull base in children with scaphocephaly to evaluate the influence of surgical repair in the remodeling of the skull base and anthropometric measures. Twenty-one children with clinical and radiological diagnosis of scaphocephaly were operated between April 2007 and October 2008, and anthropometric measures at the base of the skull were performed before and after a year of surgery. The measures were the cranial index (CI), distance between the crista galli and tuberculum sellar (CG-TS), distance between the crista galli and the internal auditory meatus (CG-IAM), distance between the oval foramen (OF-OF) distance between the internal auditory meatus (IAM-IAM), the angle of the skull base (Â1) and the angle between the nasion, center of sella and basion (Â2). There was a normalization of the CI in all children, confirming an appropriate cranial remodeling. The CG-TS measure evaluated the anterior skull base, with proportional growth of 12.5%. The mediolateral growth was observed by the increase of OF-OF measures by 8.5% and IAM-IAM by 9.5%. The CG-IAM measure grew by 7.2%. There was no statistical difference in the angles Â1 and Â2 analyzed. Surgical treatment of scaphocephaly led to remodeling of the skull base, confirmed by the changes of anthropometric measures taken before and after a year of surgery

Tropidolaemus wagleri is a species of Asian pitviper with a geographic range including Thailand, Vietnam, Malaysia, Singapore, Bruniei, parts of Indonesia, and the hilippines. Tropidolaemus is a member of the Crotalinae subfamily, within Viperidae. The genus Tropidolaemus includes five species, and was once included within the genus Trimeresurus. While some osteologic characteristics have been noted a comprehensive description of cranial elements has not been produced for T. wagleri. An in-depth description of the cranial skeleton of Tropidolaemus wagleri lays the foundation for future projects to compare and contrast other taxa within Crotalinae and Viperidae. The chosen reference specimen was compared to the presumed younger specimens to note any variation in ontogeny. The study here provides a comprehensive description of isolated cranial elements as well as a description of ontogenetic change within the specimens observed. This study contributes to the knowledge of osteological characters in T. wagleri and provides a foundation for a long term project to identify isolated elements in the fossil record.

Typescript (Photocopy) / Bibliography: leaves 243-284 / 284 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (M.D.)--Dept. of Surgery, University of Adelaide, Dept. of Surgery, 1992

Nuolat besikeičiančios aplinkos sąlygos lemia naujų tyrimų poreikį. Nemažai žinių apie Lietuvos vilkus yra pasenusios ir nebeatitinka dabartinės būklės. Moksliniam vilko populiacijos valdymo pagrindimui Lietuvoje reikia atnaujinti kai kuriuos duomenis bei atlikti papildomus tyrimus. Dalis šių darbų yra būtini, planuojant populiacijos valdymą ir apsaugą. Tikslas ir uždaviniai. Šio darbo tikslas – išsiaiškinti, kokią įtaką Lietuvos vilkų populiacijai daro aplinkos veiksniai, bei pateikti duomenis, reikalingus vilkų populiacijos valdymo planavimui. Tyrimo tikslui pasiekti išsikelti šie uždaviniai: 1. išsiaiškinti Lietuvos vilkų populiacijos kokybę pagal bioindikatorius; 2. iširti vilkų grynarūšiškumą; 3. įvertinti abiotinių, biotinių bei antropogeninių veiksnių įtaką vilkų pasiskirstymui pagal gausą biotopuose; 4. išaiškinti svarbesnius veiksnius, lemiančius vilkų teritorijos pasirinkimą. Naujumas ir originalumas. Pirmą kartą Lietuvoje įvertintas populiacijos grynumas pagal morfologinius požymius ir pagal juos nustatyti pavieniai vilko ir šuns hibridai. Pagal vilkų sumedžiojimo vietas, pirmą kartą Lietuvoje GIS technologijų pagalba išnagrinėti įvairūs abiotiniai, biotiniai ir antropogeniai veiksniai, galintys įtakoti vilkų biotopinį pasiskirstymą šalyje. Pasiūlyta, bendrą (skiriamą visai šaliai) sumedžiojimo limitą skirstyti regionais, priklausomai nuo vilkų daromos žalos, bei leisti trumpalaikę medžioklę žalos padarymo vietovėje ne medžioklės sezono laikotarpiu. Mokslinė ir... [toliau žr. visą tekstą] / A considerable amount of the data on wolves in Lithuania is out of date and is not representative of the current situation. To ensure that management of the wolf population in Lithuania is underpinned by a scientific methodology, some data needs to be updated and additional research conducted. This is a prerequisite to planning the management of the population and its protection. The objective and tasks. The objective of this work is to discover what influence environment factors have on the population of wolves of Lithuania and to present the data necessary for planning the management of the wolf population. To achieve this objective, the following tasks shall be tackled: To discover the true condition of the wolf population in Lithuania according to bio-indicators; To examine the purity of the species; To evaluate the influence of abiotic and biotic factors, as well as anthropogenic factors, on the distribution of wolves in terms of abundance in the biotopes; To discover additional important factors that influence the selection of wolf territories. Novelty and originality. An evaluation of the purity of the wolf population based on morphological features was conducted and single crosses between wolf and dog were detected for the first time in Lithuania. In areas of wolf hunting, different abiotic, biotic and anthropogenic factors that may influence the biotopic distribution of wolves were analysed with a help of GIS technologies for the first time in Lithuania. A... [to full text]

Nuolat besikeičiančios aplinkos sąlygos lemia naujų tyrimų poreikį. Nemažai žinių apie Lietuvos vilkus yra pasenusios ir nebeatitinka dabartinės būklės. Moksliniam vilko populiacijos valdymo pagrindimui Lietuvoje reikia atnaujinti kai kuriuos duomenis bei atlikti papildomus tyrimus. Dalis šių darbų yra būtini, planuojant populiacijos valdymą ir apsaugą. Tikslas ir uždaviniai. Šio darbo tikslas – išsiaiškinti, kokią įtaką Lietuvos vilkų populiacijai daro aplinkos veiksniai, bei pateikti duomenis, reikalingus vilkų populiacijos valdymo planavimui. Tyrimo tikslui pasiekti išsikelti šie uždaviniai: 1. išsiaiškinti Lietuvos vilkų populiacijos kokybę pagal bioindikatorius; 2. iširti vilkų grynarūšiškumą; 3. įvertinti abiotinių, biotinių bei antropogeninių veiksnių įtaką vilkų pasiskirstymui pagal gausą biotopuose; 4. išaiškinti svarbesnius veiksnius, lemiančius vilkų teritorijos pasirinkimą. Naujumas ir originalumas. Pirmą kartą Lietuvoje įvertintas populiacijos grynumas pagal morfologinius požymius ir pagal juos nustatyti pavieniai vilko ir šuns hibridai. Pagal vilkų sumedžiojimo vietas, pirmą kartą Lietuvoje GIS technologijų pagalba išnagrinėti įvairūs abiotiniai, biotiniai ir antropogeniai veiksniai, galintys įtakoti vilkų biotopinį pasiskirstymą šalyje. Pasiūlyta, bendrą (skiriamą visai šaliai) sumedžiojimo limitą skirstyti regionais, priklausomai nuo vilkų daromos žalos, bei leisti trumpalaikę medžioklę žalos padarymo vietovėje ne medžioklės sezono laikotarpiu. Mokslinė ir... [toliau žr. visą tekstą] / A considerable amount of the data on wolves in Lithuania is out of date and is not representative of the current situation. To ensure that management of the wolf population in Lithuania is underpinned by a scientific methodology, some data needs to be updated and additional research conducted. This is a prerequisite to planning the management of the population and its protection. The objective and tasks. The objective of this work is to discover what influence environment factors have on the population of wolves of Lithuania and to present the data necessary for planning the management of the wolf population. To achieve this objective, the following tasks shall be tackled: To discover the true condition of the wolf population in Lithuania according to bio-indicators; To examine the purity of the species; To evaluate the influence of abiotic and biotic factors, as well as anthropogenic factors, on the distribution of wolves in terms of abundance in the biotopes; To discover additional important factors that influence the selection of wolf territories. Novelty and originality. An evaluation of the purity of the wolf population based on morphological features was conducted and single crosses between wolf and dog were detected for the first time in Lithuania. In areas of wolf hunting, different abiotic, biotic and anthropogenic factors that may influence the biotopic distribution of wolves were analysed with a help of GIS technologies for the first time in Lithuania. A... [to full text]

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

Heritable ossification defects of the skull vault often present as enlarged parietal foramina (PFM), bilateral oval openings of the posterior parietal bones. Isolated PFM may originate from wider defects in infancy and usually show an autosomal dominant mode of transmission, offering unexplored genetic insights into the molecular pathways of calvarial development. Haploinsufficiency of the homeobox gene MSX2, located at 5q34-q35, underlies a fraction of PFM families but the locus can be excluded in others, indicating heterogeneity. The proximal 11p deletion syndrome (P11pDS), characterised by multiple exostoses (due to haploinsufficiency of EXT2), occasional mental retardation, and PFM, pointed to a second locus at 11p11-p12. The human orthologue of the mouse paired-like homeobox gene Alx4 was identified adjacent to EXT2. ALX4 was structurally characterised and heterozygous loss-of-function mutations were detected in association with skull vault defects in twenty-nine individuals from six families, including a new case of P11pDS. The calvarial phenotype of ALX4 mutations was almost indistinguishable from the MSX2-caused defects and ranged from a midline gap to non-penetrance, nevertheless typified by classical PFM; abnormal morphology of the dural septa was also observed. The mutation spectrum and the subtle genotype-phenotype correlations suggested haploinsufficiency as the predominant pathophysiological mechanism. Interestingly, Alx4^-/+ mice manifest polydactyly but no skull defects, illustrating species-specific dosage sensitivity. Two new MSX2 mutations were also ascertained, one of which segregated with PFM and clavicular hypoplasia. The potential contribution of ALX4 and MSX2 to premature fusion of the cranial sutures - craniosynostosis - was investigated, but no unequivocally pathogenic variants were found. To elucidate the functions of Alx4 and Msx2 in skull development, spatial expression analysis was performed in mouse embryos between embryonic days E12.5-E17. Transcripts of both Alx4 and Msx2 were seen in the early calvarial skeletogenic condensations and in later stages their expression displayed a more restricted pattern, overlapping minimally with the domains of mature bone. By assessing expression in embryonic heads of reciprocal knockout mice, activation of Alx4 was found to be independent of functional Msx2 and vice versa. Analysis of compound mutants demonstrated that the two loci exert roughly additive effects on the skull vault while protein interaction assays did not indicate any physiological interaction between Alx4 and Msx2. Hence, Alx4 and Msx2 appear to regulate proliferation, differentiation, or survival of osteoblast precursors and pre-osteoblasts through parallel pathways.

Darbo tikslas: išmatuoti Lietuvoje paplitusių pilkųjų ir baltųjų kiškių kaukoles ir nustatyti šių kiškių kaukolių morfologinius tarprūšinius skirtumus. Tyrimas buvo atliekamas Kauno Tado Ivanausko zoologijos muziejuje, naudojant šiame muziejuje esančią kiškių kaukolių kolekciją. Osteometrinei analizei naudota 29 L. europaeus, 21 L. timidus kaukolės. Makroskopinei palyginamajai analizei naudota 68 L. europaeus, 24 L. timidus kaukolės. Osteometrinei analizei atlikti buvo pasirinkti 31 matavimas. 21 matavimas atliktas remiantis F. Palacios metodika, modifikuota F. Riga ir kt. (2001 m.), 10 matavimų atlikti pagal A. von den Driesch (1976) metodiką. Matavimai atlikti elektroniniu slankmačiu 0,01 mm tikslumu. Makroskopinė palyginamoji analizė buvo atliekama remiantis F. Palacios 1998 m. metodika. Tyrimo metu tarp rūšių nustatyta 15 statistiškai patikimų matmenų (P<0,05) ir 8 makrsokopinės anatomijos tarprūšiniai skirtumai. Išvados: pilkųjų kiškių veidinė dalis yra ilgesnė ir platesnė už baltųjų kiškių. Pilkųjų kiškių kiaušo dalis yra aukštesnė už baltųjų kiškių, tačiau baltiesiems kiškiams būdinga platesnė priekinė kiaušo dalis. Bendras kaukolės ilgis tarp rūšių nesiskiria, tačiau baltųjų kiškių kaukolės yra platesnės. Atlikus tarprūšinę pilkųjų ir baltųjų kiškių kaukolių ir apatinių žandikaulių osteologinę analizę, nustatyti 7 kaukolės ir 1 apatinio žandikaulio skirtumas. / Aim: To measure the spread of European and Mountain rabbit skulls in Lithuania as well as determine the morphological differences and variations of the skulls between the species. The study was conducted at Tadas Ivanauskas Zoology Museum in Kaunas, using the collection of the rabbit skulls presented there. In terms of the study, the 29 L. europaeus, 21 L. timidus skulls were used for Osteometric analysis while 68 L. europaeus, 24 L. timidus skulls were used for macroscopic comparative analysis. During the Osteometric investigation, thirty one measurement was performed in total, in which twenty one of them was based on F. Palacios methodology (modified F.Riga et al., (2001)) while other ten were based on A. von den Driesch (1976) methodology. Measurements were performed using electronic caliper with 0.01mm accuracy. Macroscopic comparative analysis was performed with reference to F. Palacios, (1998) methodology. As a result, fifteen statistically relevant dimensions (P<0,05) were discovered along with eight macroscopic anatomical variations between the species. Conclusions: The facial part of the European rabbit skull is longer and wider when compared to the Mountain rabbit skull. In addition, the neurocranium of the European rabbit skull is higher. However, Mountain rabbits typically have wider frontal area of the neurocranium. Overall length of the skull remains the same between the species, nevertheless, white rabbits were discovered to have generally wider skulls. The... [to full text]

Following a head concussion the intracranial pressure increases due to the impact, which cannot be adequately relieved because of the stiffness of the skull. Popular strategies aimed at decompressing the head consist in the administration of osmotic agents and skull removal. The mechanical properties of bone can be affected by the administration of different solutions. If the malleability of skull is influenced by the osmotic agents that are administered to the patient then the pressure and volume in the intracranial cavity can also be modified following the treatment. In this thesis research, we hypothesize that administered osmotic agents can influence the mechanical properties of the skull, which can also impact the volume the cavity can hold and subsequently the pressure in the head. This premise was tested by modifying existing mathematical models compiled through two general MATLAB codes that allow the computation of a non-symbolic differential-algebraic initial value problem. Three main features were changed in comparison to current models: the skull's influence on the pressure and volume modulation was tested (inputs were obtained from skull tested under different solutions); pulsatile flow was accounted for on the creation and movement of cerebrospinal fluid; and the input on the mechanical behavior of the cranial vessels was accounted for through previously published continuum-mechanics vessel-behavior models. To complete the model, materials and mechanical properties were obtained through laboratory experiments as well as data collection from existing literature. From our bone test we were able to conclude that there are different factors that affect the mechanical properties of bone in various degrees. There is a mild statistical correlation (p-value 0.05) between the mechanical properties of bone obtained from different regions of the skull samples (2-14mm) and the DPBS and hDPBS solutions. Additionally there is a strong statistical difference (p-value 0.05) between the mechanical properties obtained from cross head speed (0.02, 0.002, and 0.004 (mm/s)) and solution variation (DI, DPBS and hDPBS). Finally, we were able to see that there seems to be a correlation between the mechanical properties of bone, the solution treatments and hypertension; although more test need to be developed to affirm this premise since our results are preliminary.