M-plane non-polar GaN grown on different substrates are analyzed and compared in this thesis. The crystal quality, morphology and spectra of the m-plane non-polar GaN are measured by field-emission electron microscopy (FESEM), high resolution X-ray diffraction (HRXRD), electron back-scatter diffraction (EBSD), and Cathodoluminescence (CL). The temperature dependent and acceleration voltage dependent CL spectra are compared with transmission electron microscopy (TEM) image to understand the concern of CL spectra and dislocation.

La industria de los biocombustibles est�� en su apogeo dada la preocupaci��n / ambiental que existe. El bioetanol generado a partir de lignocelulosa es bastante / prometedor, sin embargo, no se han encontrado las enzimas necesarias para hacer de su / producci��n un proceso viable a nivel industrial. En este trabajo se busc�� amplificar los / genes de al menos dos posibles celulasas putativas pertenecientes a dos organismos / distintos: Cellvibrio japonicus y Pseudomonas aeruginosa. Se procedi�� a extraer el / ADN, dise��ar oligonucle��tidos y encontrar las condiciones ��ptimas para la / amplificaci��n. Una vez lograda se hizo el an��lisis in silico completo de ambas prote��nas. / Ambos genes resultaron codificantes para dos posibles endoglucanasas: la perteneciente / a C. japonicus posee dos dominios de uni��n a la celulosa (CBD2 y CBD10) y un / dominio catal��tico perteneciente a la superfamilia 45 de las glicosil hidrolasas y se / especula es capaz de degradar celulosa cristalina. Por su parte, la posible endoglucanasa / de P. aeruginosa no pudo analizarse completamente porque los trabajos sobre las / enzimas con las que presenta homolog��a a��n no han sido publicados; sin embargo, es / probablemente una enzima termorresistente. / (cont.) Ambas enzimas resultan ser prometedoras / en la industria de biocombustibles, por lo que su clonaci��n ya est�� en proceso y su / caracterizaci��n bioqu��mica se har�� consecuentemente. Se requieren estudios posteriores / para determinar si las especulaciones aqu�� realizadas son o no verdaderas.

La Leucemia Mieloide Aguda conforma un padecimiento hematol��gico de caracter��sticas heterog��neas. Estas neoplasias, en ocasiones presentan diversas anormalidades moleculares y citogen��ticas que permiten estratificar el riesgo que representa para el paciente y proporcionar una terapia adaptada a ��ste. Dichas anormalidades funcionan como marcadores moleculares con un alto valor pron��stico para la enfermedad. Uno de los marcadores de buen pron��stico est�� representado por las mutaciones en el gen CEBPA. El objetivo principal que persigui�� este proyecto fue detectar las mutaciones en dicho gen por medio de la secuenciaci��n en 42 pacientes con LMA. Para lograr esto, se optimiz�� la amplificaci��n del gen CEBPA partiendo de lo descrito en la literatura por Ahn, J. et al en el 2009. A su vez, se determin�� la frecuencia de algunas translocaciones y mutaciones como PML-RARA, RUNX1/RUNX1T1, CBFB/MYH11, NPM1 y FLT3 y su relaci��n con el gen CEBPA. A trav��s de la secuenciaci��n, se localizaron 2 SNPs no patog��nicos reportados en m��ltiples pacientes y 5 mutaciones (12%) de variante inserci��n/deleci��n en 5 pacientes. Una de estas mutaciones se encontr�� antes del dominio de transactivaci��n del gen, provocando la formaci��n incrementada de la isoforma truncada de CEBPA, factor importante de la leucemog��nesis. / (cont.) Se reportaron dos mutaciones en el espacio intermedio entre los dominios de transactivaci��n y el dominio b��sico, 2 m��s ocurrieron entre el dominio b��sico y el cierre de leucina y otra se localiz�� en el dominio b��sico. Una mutaci��n en CEBPA se present�� junto con la translocaci��n PML/RARA y otra junto con la mutaci��n FLT3 D835X. Tres pacientes con mutaciones en CEBPA presentaron alto n��mero de blastos en general, mientras que dos de ellos presentaron CD7 aberrante y leucocitosis. En conclusi��n, el m��todo de secuenciaci��n es adecuado para localizar las mutaciones en el gen CEBPA que confieren un pron��stico favorable al paciente.

No description available.

This work presents the results of an investigation into the technique of combined TEM-Cathodoluminescence and its application to the study of GaN epitaxial layers grown by MOVPE and PAMBE on sapphire and LiAlO(_2) substrates respectively - and MOVPE grown In(_x)Ga(_1-x)N/GaN/A1(_2)O(_3) QW structures. The measurement of CL in a TEM allows spectral information to be correlated with structural information. In-situ electron beam degradation curves of panchromatic CL from GaN epilayers and In(_0.1)Ga(_0.9)N QW emission revealed a decline in the luminescence which could be attributed to the introduction of non-radiative recombination centres. The influence of thickness on both CL spectra and images was investigated experimentally and by modelling. A method of normalising STEM-CL images for thickness contrast was developed. Application of this normalisation to In(_0.1)Ga(_0.9)N QWs in cross-section revealed inhomogeneous CL with bright regions 200-700nm in width. No systematic relationship was identified between luminescence at the QW peak emission wavelength, QW(_A), and luminescence at QW(_A) ±10nm. This finding does not support the hypothesis that variation in QW CL brightness is due to local compositional fluctuation. However, clusters of threading dislocations were shown to suppress QW luminescence and are suggested as a cause for the observed inhomogeneity in luminescence. A statistical analysis of (dislocation related) V-pits in In(_x)Ga(_1-x)N MQW samples revealed clustering of pits on a length scale of 60-120nm, but no long range clustering indicative of sub-grain boundaries was found. Finally TEM-CL spectra and monochromatic line-scans were used to show that bundles of basal plane stacking faults in M-plane GaN epitaxial layers grown on LiAlO(_2) emit radiatively at 3.3-3.35eV (l00K). The radiative transition energy is consistent with models in the literature that consider basal plane stacking faults to be layers of cubic GaN in the wurtzite matrix which act as type II QWs.

O presente estudo objetivou promover incremento no desenvolvimento do concepto e aumentar a taxa de prenhez de búfalas lactantes por meio da administração de P4 injetável (P4i) três ou seis dias após a IATF. Para tanto, foram conduzidos três experimentos. No Experimento 1, foi aferido o padrão de liberação de P4 por meio da administração de P4i em 8 búfalas ovariectomizadas (delineamento crossover) nas doses 300 ou 600 mg (grupo P300 ou P600, respectivamente). Foram realizadas colheitas de sangue, para posteriores dosagens de P4, nos seguintes períodos: -24, 0, 6, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216 e 240 h da administração da P4i. No Experimento 2, 24 búfalas receberam a aplicação de 10 µg im de GnRH em dia aleatório do ciclo estral (D0). No D7, os animais receberam 0,53 mg im de PGF2α. Após 48 h (D9), foram administrados 10 µg im de GnRH e, 16 h mais tarde, todas as búfalas foram submetidas à IATF (D10). No D13, os animais foram avaliados por ultrassonografia e as fêmeas com ovulação positiva foram distribuídas em 3 grupos: Controle (C; n=8); P4D13 (n=8), que receberam 300mg de P4i no D13 e P4D16 (n=8), que receberam 300 mg de P4i no D16. No D26, as búfalas foram abatidas e os genitais removidos para a realização das seguintes avaliações: diâmetro (DCLa) e peso (PCL) do CL, presença de conceptos íntegros (pCI), íntegros e fragmentados (pCT) e comprimento do concepto (CC). Os CLs e endométrios foram seccionados, fixados e corados para aferir o percentual de células luteínicas pequenas e grandes (SLC e LLC) e o número (GEn), a área (AGEn) e o perímetro (PGEn) das glândulas do endométrio. No Experimento 3, 337 búfalas foram submetidas ao protocolo Ovsynch e, assim como no Experimento 2, as fêmeas ovuladas foram distribuídas em 3 grupos (C, n=81; P4D13, n=84 e P4D16, n=85). Foram avaliadas a funcionalidade (fluxo sanguíneo central FSC; e periférico FSP; escore de 0 a 4, em que 0 corresponde à ausência de fluxo e 4 o máximo fluxo) e o diâmetro do CL (DCL) nos D17, D21 e D25 por meio de ultrassonografia em modo color Doppler. Além disso, foram avaliadas por ultrassonografia as taxas de concepção aos 30 (DG30) e 60 (DG60) dias após a IATF e as perdas gestacionais (PG). Os dados foram analisados utilizando o procedimento GLIMMIX do SAS 9.3. Diferenças com P≤0,05 foram consideradas significativas e aquelas com 0,05<P≤0,10 foram consideradas tendência. As concentrações de P4 foram maiores no P600 em relação ao P300 em todos os pontos das colheitas de sangue (Ptrat<0,01, Ptempo=0,04, Ptrat*tempo=0,18). Verificou-se que as concentrações de P4 permaneceram acima de 1 ng/mL por aproximadamente 3 dias (entre as horas 6 e 72) no grupo P300, o que foi utilizado como critério para a dose de P4i utilizada nos Experimentos 2 e 3. Não houve diferenças entre os grupos para as variáveis avaliadas no Experimento 2: DCLa (P=0,39), PCL (P=0,13), pCI (P=0,85), pCT (P=0,41), CC (P=0,19), SLC (P=0,31), LLC (P=0,31), GEn (P=0,28), AGEn (P=0,72) e PGEn (P=0,91). No Experimento 3, houve interação tratamento*tempo (Ptrat*tempo) para as variáveis FSC (P<0,01), FSP (P<0,01) e DCL (P=0,07). Verificou-se redução do fluxo sanguíneo central e periférico e do diâmetro do CL no P4D13 em relação aos grupos C e P4D16 conforme os momentos de avaliação. Não houve diferença entre os grupos C, P4D13 e P4D16 para o DG30 (56,8 vs. 46,4 vs. 61,2 %; P=0,13) e para a PG (0,0 vs. 10,3 vs. 5,8 %; P=0,73). No entanto, houve menor taxa de concepção no DG60 para o P4D13 em comparação aos C e P4D16 (41,7b vs. 56,8a vs. 57,7a %; P=0,07). Conclui-se que o tratamento com 300 mg de P4i administrados três ou seis dias após a IATF não foi eficiente para aumentar o comprimento do concepto e a taxa de prenhez de búfalas lactantes submetidas à IATF. Ainda, o tratamento com P4i três dias após a IATF reduziu o fluxo sanguíneo central e periférico do CL, o diâmetro do CL e a taxa de prenhez. / The present study aimed to promote improvements on the conceptus development and to increase the pregnancy rate in lactating buffaloes through the administration of injectable P4 (P4i) three or six days after TAI. For this, three experiments were performed. In Experiment 1, was measured the pattern of P4 release by the P4i administration in 8 ovariectomized buffaloes (crossover design) at doses 300 or 600 mg (P300 or P600 group, respectively). Blood samples were collected for subsequent P4 dosages in the following periods: -24, 0, 6, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216 and 240 h of P4i administration. In Experiment 2, 24 buffaloes received the application of 10 µg im GnRH at random day of the estrous cycle (D0). On D7, the animals received 0.53 mg im PGF2α. After 48 h (D9), were administered 10 µg im GnRH and, 16 h later, all buffaloes underwent TAI (D10). In D13, the animals were evaluated by ultrasonography and females with positive ovulation were allocated to one of three groups: Control (C, n=8); P4D13 (n=8) that received 300 mg P4i on D13 and P4D16 (n=8), that received 300 mg P4i on D16. On D26, buffaloes were slaughtered and genitals removed to perform the following assessments: CL diameter (CLDs) and CL weight (CLW), presence of integrate conceptus (pIC), integrate and fragmented (pCT) and the conceptus length (CLe). The CLs and endometrium were sectioned, fixed and stained to assess the percentage of small and large lutein cells (SLC and LLC) and the number (GEn), the area (AGEn) and the perimeter (PGEn) of endometrial glands. In Experiment 3, 337 buffaloes were submitted to the Ovsynch protocol and, as well as in Experiment 2, the ovulated females were divided to one of three groups (C, n=81; P4D13, n=84 and P4D16, n=85). The functionality (central blood flow - CBF, and peripheral blood flow - PBF; score from 0 to 4, where 0 corresponds to absence of flow and 4 the maximum flow) and the CL diameter (CLD) were evaluated on D17, D21 and D25 by ultrasonography in color Doppler mode. Furthermore, the conception rates at 30 (CR30) and 60 (CR60) days after TAI, and pregnancy loss (PL) were evaluated by ultrasonography. Data were analyzed using the GLIMMIX procedure of SAS 9.3. Differences were considered significant with P≤0.05 and those with 0.05<P≤0.10 were considered tendencies. The P4 concentrations were higher in the P600 compared to P300 in all points of blood sampling (Ptreat<0.01, Ptime=0.04, Ptreat*time=0.18). It was found that the P4 concentrations remained above 1.0 ng/ml for approximately 3 days (between hours 6 and 72) in the P300 group, which was used as standard for P4i dose used in Experiments 2 and 3. There were no differences between the groups for the variables evaluated in Experiment 2: CLDs (P=0.39), CLW (P=0.13), pCI (P=0.85), pCT (P=0.41), CoLe (P=0.19), SLC (P=0.31), LLC (P=0.31), GEn (P=0.28), AGEn (P=0.72) and PGEn (P=0.91). In Experiment 3, there was interaction treatment*time (Ptreat*time) for the CBF (P<0.01), PBF (P<0.01) and CLD (P=0.07). There was a reduction of the central blood flow, peripheral blood flow and CL diameter for P4D13 compared to C and P4D16 groups according to the evaluation moments. There was no difference between C, P4D13 and P4D16 groups for the CR30 (56.8 vs. 46.4 vs. 61.2 %; P=0.13) and for the PL (0.0 vs. 10.3 vs. 5.8 %; P=0.73). However, there was lower conception rate in CR60 for P4D13 compared to C and P4D16 (41.7b vs. 56.8a vs. 57.7a %; P=0.07). It was concluded that treatment with 300 mg P4i administered three or six days after TAI was not efficient to increase the conceptus length and the pregnancy rate in lactating buffaloes submitted to TAI. Furthermore, the treatment with P4i three days after TAI reduced the central and the peripheral CL blood flow, the CL diameter and the pregnancy rate.

O presente estudo objetivou promover incremento no desenvolvimento do concepto e aumentar a taxa de prenhez de búfalas lactantes por meio da administração de P4 injetável (P4i) três ou seis dias após a IATF. Para tanto, foram conduzidos três experimentos. No Experimento 1, foi aferido o padrão de liberação de P4 por meio da administração de P4i em 8 búfalas ovariectomizadas (delineamento crossover) nas doses 300 ou 600 mg (grupo P300 ou P600, respectivamente). Foram realizadas colheitas de sangue, para posteriores dosagens de P4, nos seguintes períodos: -24, 0, 6, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216 e 240 h da administração da P4i. No Experimento 2, 24 búfalas receberam a aplicação de 10 µg im de GnRH em dia aleatório do ciclo estral (D0). No D7, os animais receberam 0,53 mg im de PGF2α. Após 48 h (D9), foram administrados 10 µg im de GnRH e, 16 h mais tarde, todas as búfalas foram submetidas à IATF (D10). No D13, os animais foram avaliados por ultrassonografia e as fêmeas com ovulação positiva foram distribuídas em 3 grupos: Controle (C; n=8); P4D13 (n=8), que receberam 300mg de P4i no D13 e P4D16 (n=8), que receberam 300 mg de P4i no D16. No D26, as búfalas foram abatidas e os genitais removidos para a realização das seguintes avaliações: diâmetro (DCLa) e peso (PCL) do CL, presença de conceptos íntegros (pCI), íntegros e fragmentados (pCT) e comprimento do concepto (CC). Os CLs e endométrios foram seccionados, fixados e corados para aferir o percentual de células luteínicas pequenas e grandes (SLC e LLC) e o número (GEn), a área (AGEn) e o perímetro (PGEn) das glândulas do endométrio. No Experimento 3, 337 búfalas foram submetidas ao protocolo Ovsynch e, assim como no Experimento 2, as fêmeas ovuladas foram distribuídas em 3 grupos (C, n=81; P4D13, n=84 e P4D16, n=85). Foram avaliadas a funcionalidade (fluxo sanguíneo central FSC; e periférico FSP; escore de 0 a 4, em que 0 corresponde à ausência de fluxo e 4 o máximo fluxo) e o diâmetro do CL (DCL) nos D17, D21 e D25 por meio de ultrassonografia em modo color Doppler. Além disso, foram avaliadas por ultrassonografia as taxas de concepção aos 30 (DG30) e 60 (DG60) dias após a IATF e as perdas gestacionais (PG). Os dados foram analisados utilizando o procedimento GLIMMIX do SAS 9.3. Diferenças com P≤0,05 foram consideradas significativas e aquelas com 0,05<P≤0,10 foram consideradas tendência. As concentrações de P4 foram maiores no P600 em relação ao P300 em todos os pontos das colheitas de sangue (Ptrat<0,01, Ptempo=0,04, Ptrat*tempo=0,18). Verificou-se que as concentrações de P4 permaneceram acima de 1 ng/mL por aproximadamente 3 dias (entre as horas 6 e 72) no grupo P300, o que foi utilizado como critério para a dose de P4i utilizada nos Experimentos 2 e 3. Não houve diferenças entre os grupos para as variáveis avaliadas no Experimento 2: DCLa (P=0,39), PCL (P=0,13), pCI (P=0,85), pCT (P=0,41), CC (P=0,19), SLC (P=0,31), LLC (P=0,31), GEn (P=0,28), AGEn (P=0,72) e PGEn (P=0,91). No Experimento 3, houve interação tratamento*tempo (Ptrat*tempo) para as variáveis FSC (P<0,01), FSP (P<0,01) e DCL (P=0,07). Verificou-se redução do fluxo sanguíneo central e periférico e do diâmetro do CL no P4D13 em relação aos grupos C e P4D16 conforme os momentos de avaliação. Não houve diferença entre os grupos C, P4D13 e P4D16 para o DG30 (56,8 vs. 46,4 vs. 61,2 %; P=0,13) e para a PG (0,0 vs. 10,3 vs. 5,8 %; P=0,73). No entanto, houve menor taxa de concepção no DG60 para o P4D13 em comparação aos C e P4D16 (41,7b vs. 56,8a vs. 57,7a %; P=0,07). Conclui-se que o tratamento com 300 mg de P4i administrados três ou seis dias após a IATF não foi eficiente para aumentar o comprimento do concepto e a taxa de prenhez de búfalas lactantes submetidas à IATF. Ainda, o tratamento com P4i três dias após a IATF reduziu o fluxo sanguíneo central e periférico do CL, o diâmetro do CL e a taxa de prenhez. / The present study aimed to promote improvements on the conceptus development and to increase the pregnancy rate in lactating buffaloes through the administration of injectable P4 (P4i) three or six days after TAI. For this, three experiments were performed. In Experiment 1, was measured the pattern of P4 release by the P4i administration in 8 ovariectomized buffaloes (crossover design) at doses 300 or 600 mg (P300 or P600 group, respectively). Blood samples were collected for subsequent P4 dosages in the following periods: -24, 0, 6, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216 and 240 h of P4i administration. In Experiment 2, 24 buffaloes received the application of 10 µg im GnRH at random day of the estrous cycle (D0). On D7, the animals received 0.53 mg im PGF2α. After 48 h (D9), were administered 10 µg im GnRH and, 16 h later, all buffaloes underwent TAI (D10). In D13, the animals were evaluated by ultrasonography and females with positive ovulation were allocated to one of three groups: Control (C, n=8); P4D13 (n=8) that received 300 mg P4i on D13 and P4D16 (n=8), that received 300 mg P4i on D16. On D26, buffaloes were slaughtered and genitals removed to perform the following assessments: CL diameter (CLDs) and CL weight (CLW), presence of integrate conceptus (pIC), integrate and fragmented (pCT) and the conceptus length (CLe). The CLs and endometrium were sectioned, fixed and stained to assess the percentage of small and large lutein cells (SLC and LLC) and the number (GEn), the area (AGEn) and the perimeter (PGEn) of endometrial glands. In Experiment 3, 337 buffaloes were submitted to the Ovsynch protocol and, as well as in Experiment 2, the ovulated females were divided to one of three groups (C, n=81; P4D13, n=84 and P4D16, n=85). The functionality (central blood flow - CBF, and peripheral blood flow - PBF; score from 0 to 4, where 0 corresponds to absence of flow and 4 the maximum flow) and the CL diameter (CLD) were evaluated on D17, D21 and D25 by ultrasonography in color Doppler mode. Furthermore, the conception rates at 30 (CR30) and 60 (CR60) days after TAI, and pregnancy loss (PL) were evaluated by ultrasonography. Data were analyzed using the GLIMMIX procedure of SAS 9.3. Differences were considered significant with P≤0.05 and those with 0.05<P≤0.10 were considered tendencies. The P4 concentrations were higher in the P600 compared to P300 in all points of blood sampling (Ptreat<0.01, Ptime=0.04, Ptreat*time=0.18). It was found that the P4 concentrations remained above 1.0 ng/ml for approximately 3 days (between hours 6 and 72) in the P300 group, which was used as standard for P4i dose used in Experiments 2 and 3. There were no differences between the groups for the variables evaluated in Experiment 2: CLDs (P=0.39), CLW (P=0.13), pCI (P=0.85), pCT (P=0.41), CoLe (P=0.19), SLC (P=0.31), LLC (P=0.31), GEn (P=0.28), AGEn (P=0.72) and PGEn (P=0.91). In Experiment 3, there was interaction treatment*time (Ptreat*time) for the CBF (P<0.01), PBF (P<0.01) and CLD (P=0.07). There was a reduction of the central blood flow, peripheral blood flow and CL diameter for P4D13 compared to C and P4D16 groups according to the evaluation moments. There was no difference between C, P4D13 and P4D16 groups for the CR30 (56.8 vs. 46.4 vs. 61.2 %; P=0.13) and for the PL (0.0 vs. 10.3 vs. 5.8 %; P=0.73). However, there was lower conception rate in CR60 for P4D13 compared to C and P4D16 (41.7b vs. 56.8a vs. 57.7a %; P=0.07). It was concluded that treatment with 300 mg P4i administered three or six days after TAI was not efficient to increase the conceptus length and the pregnancy rate in lactating buffaloes submitted to TAI. Furthermore, the treatment with P4i three days after TAI reduced the central and the peripheral CL blood flow, the CL diameter and the pregnancy rate.

In this research, we used the zinc oxide (ZnO) which is die pressed and sintered for studying. We want to know the variations of microstructure and luminescence property when we doped 0.2 mol.% Al2O3 or Li2O to ZnO, or sintered under different atmospheres (high purity oxygen, high purity nitrogen, high purity argon). Using X-ray diffractometry (XRD), scanning electron microscope (SEM), and catholuminescence (CL) spectrometry equipped with a SEM to analyze the different samples. The all six samples¡¦ crystal structure didn¡¦t change via XRD. We investigated for the in-gap-level modification using the CL spectrometry. CL analysis results indicated that ZnO emitted UV light, visible light (blue, green, yellow light), and Near-infrared light emissions. The UV light emission was attributed to the two electronic transitions from the donor level of free exciton and Zn interstitial to valence band. The blue light (2.53 eV) emission was attributed to the donor level of oxygen vacancy-related defect. The green light emission was attributed to the electronic transition from the acceptor level of zinc vacancy-related defect.And the yellow light emission was attributed to the O interstitial and Li-related defects. The Near-infrared light may be attributed to the deep levels recombination.

The involvement of clock genes in the temporal regulation of the function and lifespan of the corpus luteum (CL) has not been investigated in detail. Immunohistochemistry and real-time quantitative PCR techniques were used to examine the expression of the canonical clock genes: period1, period2, period3, cryptochrome1, cryptochrome2, clock and bmal1, at protein and mRNA levels respectively. The expression of the clock genes was examined in the human CL, cultured luteinised granulosa cells, cultured luteal fibroblast-like cells and the ovine CL. The main findings were that clock genes are expressed in the human and ovine CL; that this expression is manifest at mRNA and protein level in all discernible cell types within the human and ovine CL, and that the pattern of mRNA expression differs between the early luteal phase compared to the late luteal phase. The circadian expression of the clock genes was established in the ovine CL during the late luteal phase and could not be determined in the human CL, although indications from cultured luteinised granulosa cells and luteal fibroblast-like cells suggest that this may also be the case in humans. With the exception of per2, the circadian pattern of clock gene expression emerged in the late luteal phase CL when the early luteal phase CL did not demonstrate circadian clock gene expression. This emergence later in the lifespan of the CL was akin to that observed in embryonic development, where the clock genes are initially non-rhythmic but then acquire circadian rhythmicity with age. In this case, the clock genes have been proposed to perform a non-classical circadian timing role in the timing of embryonic development. The per2 gene was also found to be special, in its loss rather than gain of rhythmic gene expression across the luteal lifespan and in its protein localisation in the cytoplasm of some granulosa-lutein cells. The exceptional behaviour of per2 is consistent with a growing body of evidence supporting its role as a unique clock gene in many respects, able to maintain circadian protein levels in the absence of circadian gene expression, integrating peripheral clock inputs and outputs and acting as a tumour suppressor gene. The CL was also found to be a potential target of melatonin regulation, based on its possession of melatonin MT1 receptors and the timing of circadian cry1 gene expression in the late luteal phase. The expression of cry1 is known to be directly melatonin-induced in the PT and appeared to be similarly activated, downstream of a melatonin signal, in the CL. This supports the evolving view of a hierarchical organisation of the central and peripheral clocks, which are integrated in order to establish information feedback loops that maintain circadian homeostasis, and which can regulate seasonal physiology.

Made available in DSpace on 2018-08-01T23:26:20Z (GMT). No. of bitstreams: 1 tese_9339_DISSERTAÇÃO FINAL.pdf: 516782 bytes, checksum: f8a8e0ac8e3f39b30abbc544c45a8cf3 (MD5) Previous issue date: 2015-11-09 / Apesar do uso dos implantes osseointegrados ter se tornado uma excelente opção em substituição aos elementos dentários perdidos, um problema cada vez mais relacionado a essa terapia são as complicações inflamatórias denominadas doenças periimplantares. A semelhança observada na microbiota subgengival encontrada em bolsas periodontais e periimplantares, demonstrada por alguns estudos, tem levantado a hipótese de que pacientes, com história de doença periodontal prévia, poderiam apresentar maior risco de desenvolver periimplantite. Este estudo buscou comparar a condição periimplantar de implantes unitários, instalados em substituição a dentes perdidos por doença periodontal (Grupo A), com aqueles perdidos por outros fatores etiológicos (Grupo B). Quarenta e seis implantes unitários, instalados em 21 indivíduos e em função por um período superior a cinco anos, foram avaliados. Os seguintes parâmetros clínicos periimplantares foram registrados: índice de placa, índice gengival, profundidade de sondagem e sangramento à sondagem. A composição da microbiota subgengival foi analisada através da técnica Checkerboard DNA-DNA Hybridization, em amostras coletadas de biofilme subgengival dos 46 implantes que compuseram a amostra. Após a análise dos dados, observou-se que os implantes do Grupo A apresentaram maior profundidade de sondagem (5,30 ± 1,11 vs 4,61 ± 1,37) e maior porcentagem de sítios com sangramento gengival (86,96% vs 47,83%), quando comparados aos implantes do Grupo B, respectivamente (p<0,05). Em relação aos resultados microbiológicos, observou-se que, em ambos os grupos, o perfil de colonização da placa subgengival foi semelhante. Entretanto, três espécies bacterianas, do complexo vermelho, estavam presentes em número significativamente maior no grupo A (P. gingivalis, T. forsythia e T. denticola). O estudo demonstrou que os implantes, que substituíram dentes perdidos por doença periodontal, apresentaram maior profundidade de sondagem e maior índice gengival do que os observados nos implantes que substituíram dentes perdidos por outros fatores etiológicos. Além disso, três espécies bacterianas, do complexo vermelho, estavam presentes em níveis mais elevados no grupo de implantes que substituíram os dentes perdidos por doença periodontal.