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]

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This thesis investigates aspects of the community ecology of rabbit parasites with particular emphasis upon the gut helminths, utilising a 23 (later extended to 26) year time series of rabbits and their parasites. A clearer understanding of parasite communities can lead to more effective biological control strategies. Rabbits are regarded as a serious pest species throughout Europe and the Antipodes and the use of the myxomatosis virus, as a biological control agent, has already been tried and failed. However, a clearer picture of the parasite community may offer future possibilities for control. Additionally, the rabbit is a good model for other grazing species, as it carries a similar gut helminth community. Drug resistance is an increasing problem in a wide range of parasites. A clearer appreciation of parasite communities could also aid in the search for effective and environmentally sound pathogen control strategies (e.g. via cross immunity or competition with benign species). Theoretical models have revealed the importance of aggregation to the stability of the host parasite relationship, to parasite evolution and to interspecific parasite interactions. A number of models have considered the effect of varying aggregation upon these dynamics with differing outcomes to those where aggregation was a fixed parameter. Here the stability of the distribution for each of the rabbit helminths was examined using Taylor's power law. The analyses revealed that aggregation was not a stable parameter but varied with month, year, host sex, host age, and host myxomatosis status. Evidence for the existence of interspecific parasite interactions in natural systems has been equivocal. Factors influencing parasite intensity were evaluated for the gut helminth. A network of potential interactions between the parasites was revealed. Only month was shown to be of greater influence on the community. Following, from the above analyses, a community model was constructed which incorporated both seasonal forcing and interspecific parasite interactions, with interaction mediated via host immunity. One unexpected emergent property was an interaction between the seasonality and the immune decay rate with slower immune decay resulting in a shift of the immune response out of phase with the species against which it was produced. The model was also used to assess the potential effects of two control strategies, an anticestodal and a single species vaccine. The vaccine had greater effects on the whole community than the anticestodal because of the immune- mediated interactions. The host is also an integral part of the community as the parasite dynamics are linked with that of their host. Therefore an assessment of the parasites' impact upon host condition and fecundity was also undertaken. This revealed a variety of positive and negative associations between the parasites and their host, with potential implications for future host control strategies. This study has shown that ignoring parasite-parasite or parasite-host interactions and interactions of both the host and the parasite with the external environment, could result in a poor description of the community dynamics. Such complexities need to be considered and incorporated into theory if future control strategies for either host or parasites are to be effective.

La physique attoseconde est un domaine en pleine expansion, intrinsèquement lié au processus de génération d’harmoniques d’ordre élevé. Cette émission, sous forme d’un train d’impulsions attosecondes ou d’une impulsion attoseconde isolée, constitue une source de lumière dans le domaine spectral extrême-UV (XUV), ultra-brève, cohérente, parfaitement synchrone du champ générateur. Deux thématiques ont été abordées. La première consiste en la caractérisation complète de l’état de polarisation des harmoniques par Polarimétrie Moléculaire en collaboration avec l’ISMO-Orsay. Cette technique est basée sur la mesure de la distribution angulaire des photoélectrons dans le référentiel moléculaire lors de l’ionisation dissociative de la molécule de NO. Nous l’appliquons à trois configurations produisant un rayonnement harmonique polarisé elliptiquement. Nous obtenons ainsi, pour la première fois, la valeur absolue de l’ellipticité harmonique, son signe, ainsi que le taux de dépolarisation.La seconde thématique est la photoionisation attoseconde résonante : nous avons étudié la photoionisation de l’hélium au voisinage de la résonance d'autoionisation 2s2p à 60.15eV, excitée par une impulsion XUV accordable et sondée par une impulsion laser IR en utilisant la technique RABBIT, qui permet la mesure de l’amplitude et de la phase spectrales de la transition résonante à deux photons. Il est ainsi possible de reconstruire dans le domaine temporel, le paquet d'ondes électronique (POE) à 2 photons. Ces mesures ont été complétées par des simulations effectuées par nos collaborateurs à UAM-Madrid et au LCPMR-Paris, qui montrent que, dans nos conditions expérimentales, ce paquet à deux photons est une image fidèle du paquet résonant à un photon. Ceci représente la première reconstruction de la dynamique temporelle d’une résonance non perturbée par le champ laser, avec une résolution attoseconde. / Attosecond physics is an expending field, intrinsically linked to the High Harmonic Generation process. This emission, which can be either an attosecond pulse train or an isolated attosecond pulse, constitutes a light source in the extreme-UV (XUV) spectral domain, coherent, perfectly synchronous of the generating field. Two thematic have been studied. The first one consists in the complete characterization of the harmonic emission through Molecular Polarimetry, in collaboration with ISMO-Orsay. This technique is based on the measurement of the Molecular Frame PhotoElectron Angular Distribution, during the dissociative ionization of NO molecules. We applied this technique to three configurations producing an elliptically polarized light. For the first time, we obtain the absolute value of the ellipticity, its sign and the depolarization rate. The second topic is the resonant attosecond photoionization: we studied the photoionization of helium, close to the 2s2p autoionization resonance at 60.15 eV, excited by a tunable XUV pulse and probed by an IR pulse, using RABBIT technique, enabling the measurement of the spectral amplitude and phase of the two photons resonant transition. From this, we can reconstruct the two-photons electron wave packets (EWP). These measurements have been completed by simulations done by our collaborator from UAM-Madrid and LCPMR-Paris, showing that, in our experimental conditions, this two photons EWP corresponds to the image of the one-photon EWP. This measurement is the first reconstruction of the temporal dynamic of a resonance non-perturbed by a laser field, with an attosecond resolution.

Brain-derived neurotrophic factor (BDNF) belongs to the neurotrophin family of secreted proteins, which include in addition to BDNF, nerve growth factor (NGF) and neurotrophin 3-6 (NT-3-6). BDNF mediates its functions by activating two cell surface receptors, pan-neurotrophin receptor (P75NTR) and tropomyosin-related kinase B (TrkB) and their downstream intracellular cascades. BDNF is best known for its role in neuronal survival, regulation of neuronal differentiation, migration and activity-dependent synaptic plasticity. However, BDNF is widely expressed in non-neuronal tissues as well. The localization and the function of BDNF in intestinal smooth muscle cells (SMCs) are not well defined. Thus, the main purpose of the present study was the identification and characterization of BDNF in intestinal SMCs. Using xviii biochemical and molecular techniques, we have demonstrated in this study that BDNF is synthesized and released in rabbit intestinal longitudinal SMCs cultures. Furthermore, gut neuropeptides, Pituitary Adenylate Cyclase Activating Peptide (PACAP) and substance P (SP) increased BDNF expression and release in SMCs cultures after 24 hrs and 48 hrs incubation. We have also shown that intracellular Ca2+ levels are essential for SP stimulation of BDNF expression and secretion. Lastly, we have demonstrated that exogenous BDNF enhanced carbachol (CCh)-induced contraction of isolated longitudinal muscle strips, and this was inhibited by preincubation with TrkB inhibitor K252a and PLC inhibitor U73122 sugesting that BDNF sensitize longitudinal SMCs to CCh by activating PLC pathway, which is normally absent in those muscle cells. These results provide new insight into the mechanisms of neurotrophin (BDNF) modulation of gut function, which may lead to new therapeutic avenues for treatment of gastrointestinal disorders, and explain some of the pathological changes associated with inflammation such as hypercontractility associated with gut infection or IBD.

Reforestation of bottomland hardwood (BLH) forests has occurred within the Lower Mississippi Alluvial Valley (LMAV), USA, to support a wide range of ecosystem services, but especially wildlife habitat enhancement. As ecosystem restoration efforts proceed in BLH ecosystems, managers and policymakers are seeking criteria to evaluate wildlife habitat enhancement goals. Specialist wildlife that evolved within forest ecosystems can be sensitive to the composition, structure, and function of an ecosystem in relation to the system's natural or historical range of variation and thereby serve as indicators of habitat quality. The swamp rabbit (Sylvilagus aquaticus) is a specialist of BLH forests throughout the LMAV and therefore may be an appropriate indicator species for this ecosystem. In Chapter 1, I reviewed peer-reviewed literature to evaluate the utility of swamp rabbits as an indicator species according to three commonly-used criteria: habitat factors defining swamp rabbit relationships to BLH forests, the importance of swamp rabbit habitat to other wildlife, and the efficiency of swamp rabbit monitoring. I concluded that the swamp rabbit is a suitable indicator of wildlife habitat quality in BLH ecosystems in the LMAV because they evolved and remain endemic to the ecosystem, use habitat that integrates desirable characteristics that positively influence wildlife biodiversity, and are easy to monitor routinely.

A ingestão de dietas com níveis elevados de flúor interfere na mineralização óssea e, conseqüentemente, poderá influenciar nas propriedades mecânicas dos ossos. Este trabalho teve como objetivo estudar e avaliar algumas propriedades mecânicas de fêmures de coelhos submetidos a dietas com diferentes concentrações de flúor, mediante ensaios mecânicos de flexão em três pontos. Foram utilizados os fêmures de 40 coelhos machos, albinos, da raça Nova Zelândia com 1 mês de idade. Durante 40 dias os animais, divididos em 5 grupos, receberam dietas contendo diferentes concentrações de flúor. As propriedades mecânicas da deformação proporcional e resiliência, apresentaram diferença estatisticamente significante. Houve redução nos valores para rigidez, tensão máxima, carga máxima, mas sem diferença estatisticamente significante, para os grupos com maior concentração de flúor. Diante destas considerações e dos achados neste trabalho, fica evidente a necessidade de mais investigações para caracterizar a relação entre o flúor e as propriedades mecânicas. / High levels of fluoride ingestion may interfere with bone mineralization and, therefore, cause modification in the bone mechanical properties. In this investigation we studied the relationship between some mechanical properties of the rabbit femur and different concentration of fluoride in the diets. It was performed the three bending test in forty femurs obtained from New Zealand white rabbits that had been fed with diet with different fluoride concentration during 40 days since they were one month old. The animals were divided into 5 different groups according to the fluoride concentration in diets. The resilience and proportional deformation were higher for the group with the highest fluoride ingestion and there was no difference among the other groups. Rigidity, ultimate load and tension were lower as fluoride concentration increased but with no statistical difference. It was concluded that more investigation is necessary to establish the relationship of the mechanical properties with fluoride intake.

As células tronco possuem a capacidade de auto renovação ilimitada e de se manterem indiferenciadas durante um período prolongado de tempo, até se diferenciarem em uma linhagem celular específica. Devido as dificuldades encontradas na utilização de células embrionárias por questões éticas, de segurança e histocompatibilidade e a limitada plasticidade das células tronco adultas, as células tronco fetais, derivadas de tecidos extraembrionários, aparecem no cenário terapêutico como uma alternativa promissora. Uma vez que apresentam alta capacidade de proliferação e expansão in vitro, além de sua característica imunogênica, por se encontrarem na interface materno fetal. Por conta destas características, a membrana amniótica surgiu como uma nova e importante fonte de células tronco em diferentes espécies. Neste trabalho, foram utilizados 8 fetos de coelhos para a coleta da membrana amniótica. A membrana foi isolada pela técnica de explante, as amostras foram cultivadas em meio DMEM-HIGH, e posteriormente criopreservadas nas passagens P4 e P8 para realizar os experimentos. Em cultivo, essas células apresentaram aderência a placa, alta capacidade de proliferação e morfologia semelhante à fibroblastos. Na caracterização imunofenotípica, houve expressão de marcadores de citoesqueleto, de células mesenquimais, proliferação, pluripotência e para precursores de células hematopoiéticas, embora não tenha ocorrido a expressão de marcadores de células hematopoiéticas (CD-45) e de células precursoras neuronais. Quando induzidas a diferenciação in vitro, as células amnióticas tiveram capacidade de se diferenciarem nas linhagens osteogênica, adipogênica e condrogênica. Além disso, quando injetadas em camundongos nude, não foi verificada a formação de tumor. Nossos resultados demostram que células de membrana amniótica de coelho podem ser consideradas células tronco mesenquimais com possibilidade de serem utilizadas no futuro na terapia celular / Stem cells are capable of unlimited self renewal and to remain undifferentiated for a prolonged period of time up to differentiate into a specific cell lineage. Due to the difficulties in the use of embryonic cells due ethical reasons, security and histocompatibility, and in the other hands, the limited plasticity of adult stem cells, fetal stem cells, derived from extraembryonic tissues, appear in the therapeutic setting as a promising alternative. They have high capacity of proliferation and in vitro expansion, as well as immunogenic properties, since they are at the maternal-fetal interface. Due to these characteristics, the amniotic membrane has emerged as an important new source of stem cells in different species. In this work, we used 8 fetuses of rabbits to collect amniotic membrane. The membrane was isolated by the explant technique. Samples were cultured in DMEM-HIGH, and cryopreserved in the passages P4 and P8 in order to perform the experiments. In culture, these cells exhibited adhesion to the dishes, high proliferative capacity and fibroblast-like morphology. In immunophenotypic characterization, there was expression of markers related to cell cytoskeleton, mesenchymal stem cells, proliferation, pluripotency, and hematopoietic precursor cells. And there was no expression of hematopoietic cell markers (CD-45) and neuronal precursor cells. When induced to in vitro differentiation, the amniotic cells were able to differentiate in osteogenic, adipogenic and chondrogenic lineages. Furthermore, when injected into nude mice, tumor formation has not been verified. Our results demonstrate that rabbit amniotic membrane cells can be considered mesenchymal stem cells with possibility to be used in the future in cell therapy

Foi estudada a ação de preenchimento e de osteocondução em perfurações em tíbias de coelhos, que receberam a aplicação de um biovidro em pó cuja composição é (teor % m/m): 45,9 SiO2, 23,9 Na2O, 21,6 CaO e 7,54 P2O5. Foram realizadas perfurações nas tuberosidades das tíbias direitas de 24 coelhos, machos, adultos da raça Nova Zelândia, com peso entre 2,6 e 4,0 quilogramas. Foi utilizado sangue do próprio coelho misturado ao vidro para facilitar a colocação do material nas perfurações. Foram realizadas radiografias, microscopia de luz comum, microscopia eletrônica de varredura (MEV) e espectroscopia dispersiva de raios-X buscando revelar a interação do vidro com o osso. A caracterização do material foi realizada por meio das técnicas de análise térmica diferencial, difração de raios-X, MEV e avaliação do potencial de citotoxicidade in vitro do material. Os resultados indicam que o material não sofreu rejeição pelo organismo dos coelhos e que houve formação de osso na região em que foi implantado o material. Foi observada a presença de células ósseas e de tecido osteóide bem irrigados. / In this research were studied both filling and osteoconduction action in rabbit tibiae, which received a powder bioactive glass of de following composition (45,9% SiO2, 23,9% Na2O, 21,6% CaO, 7,54% P2O5, all in wt%). It was carried out in right tibiae tuberosity perfurations of 24 New Zealand white, male, mature rabbits weighing between 2.6 e 4.0 Kg. There was used animal’s autologous blood mixed with bioactive glass to facilitate its placed in tibia. It were observed in tibia tuberosity perfurations findings by means of radiography, light microscopy, SEM and EDS to show bone tissue and bioactive glass interaction. Material characterization was made by chemical composition analysis, SEM, DTA, XRD analysis and evaluation of cytotoxicity potential in vitro. Results indicated that material was biocompatible and acted as a osteoconductive material. Both bone cells and osteid tissue were found with satisfactory blood irrigation.

Made available in DSpace on 2014-06-11T19:22:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-16Bitstream added on 2014-06-13T18:07:54Z : No. of bitstreams: 1 brandao_sm_me_botfm.pdf: 3665016 bytes, checksum: 75fc54153ef156f5ca956b6030a55db2 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A reposição do volume perdido nas cavidades enucleadas e evisceradas é feita há muitos anos. O vidro foi o primeiro material utilizado para este fim, seguido por uma série de outros, sem que nenhum deles possa ser considerado como o material ideal. Mais recentemente, o vidro ou melhor, o biovidro, voltou ao cenário das reconstruções em outras áreas da Medicina, levantando-se a hipótese do uso destes em cavidade anoftálmica. Avaliar experimentalmente a biocompatibilidade de cones de biovidro, biovitrocerâmico I e biovitrocerâmico II em cavidades evisceradas de coelhos. Foram utilizados 51 coelhos albinos, espécie Orictolagus cuniculus, submetidos a cirurgia de evisceração do olho direito, seguida da inclusão de cones na cavidade escleral. Os animais foram divididos em três grupos (G) que diferiram pelo tipo de biomaterial de que eram feitos os cones: cones de biovidro (GA), cones de biovitrocerâmico I (GB) e cones de biovitrocerâmico II (GC). Os animais foram sacrificados em três momentos (M) experimentais: sete (M1), 90 (M2) e 180 (M3) dias após a colocação dos cones na cavidade eviscerada. Os parâmetros avaliados foram: peso no início e ao final do período experimental; exame clínico diário; exames bioquímicos (TGO, TGP, CPK, FA, LDH, Uréia e Creatinina) imediatamente antes do procedimento cirúrgico e nos momentos de sacrifício; avaliação histológica do conteúdo orbitário e exame morfométrico da pseudocápsula e celularidade formada ao redor dos cones nos momentos de sacrifício; estudo tomográfico da órbita 45 dias após a evisceração e colocação dos cones; e microscopia eletrônica de varredura, realizada em seis coelhos no M3. O exame clínico e os exames bioquímicos dos animais mostraram que os animais mantiveram-se saudáveis durante o experimento. Houve boa integração dos cones com os tecidos do hospedeiro em todos os grupos e em todo... / Replacement of lost volume in eviscerated and enucleated cavities has been performed for many years. Glass was the first material for this purpose, followed by a number of others, although none of them could be considered an ideal one. Recently, bioglass made its return at the reconstruction scenery, bringing up the hypothesis of its use in anophthalmic cavity. To evaluate bioglass, bioglassceramic and bioglassceramic II biocompatibility in rabbit’s eviscerated cavities. 51 rabbitis were used, species Orictolagus cuniculus, all submitted to right eye evisceration surgery, followed by the inclusion of protheses in the escleral cavity. Those animals were gathered in 3 groups (G), distinguished through the type of material used to manufacture the cones: bioglass (GA), bioglassceramic (GB) and bioglassceramic II (GC). The animals were sacrificed at three distinctive experimental moments (M): 7 (M1), 90 (M2) and 180 (M3) days after the placement of cones in eviscerated cavities. The parameters evaluated were: daily clinical exam; biochemical exam (AST, ALT, CK, AP, HDL, urea and creatinine) before surgery and sacrifice; histological analysis; morphometric evaluation; ocular tomography 45 days after surgery; and scanning electron microscopy evaluation in six rabbits in M3. Clinical and biochemical examination led to the conclusion that the animals stayed healthy during the experiment. There was good cone integration with the host tissue in every group and throughout every experimental moment, having occurred extrusion in none of the animals. Histologically, it was observed pseudocapsule formation around the cones, composed of fibrovascular reaction, neovases, low amount of erythrocyte and inflammatory cells. Morphometric evaluation showed that the inflammatory reaction was higher at M1, getting progressively lower while getting at M3, being the lowest in rabbits which received ... (Complete abstract click access electronic below)