Made available in DSpace on 2014-06-11T19:27:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-02-11Bitstream added on 2014-06-13T19:15:15Z : No. of bitstreams: 1 pretel_h_me_arafo_prot.pdf: 4958895 bytes, checksum: 2233125e5e1962443593d9b99271bb22 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A poliuretana derivada do óleo de mamona propicia estimulação na reparação óssea por apresentar propriedades de osteocondutividade auxiliando na neoformação óssea. Quanto a osteoindução, pode ser estimulada por fatores de crescimento, como a BMP, e por fatores físicos como o laser. O trabalho avaliou a regeneração óssea a partir da confecção de uma lesão na base da mandíbula de rato, preenchida com mamona particulada, acrescida do pool de BMP E Hidroxiapatita (HA) absorvível. Posteriormente aplicou-se ou não um estímulo local com o laser de baixa intensidade. O aparelho utilizado foi o Laser beam (Semicondutor de Arseneto de Gálio-Alumínio, infravermelho - 785nm, 35mW). Foram usados 60 ratos Holtzman, divididos em quatro grupos de 15 animais, e estes subdivididos em 5 animais por período de análise, da seguinte forma: Grupo Controle (somente defeito); Grupo Experimental com estimulação laser (dose=178J/cm2; energia=1,4J); Grupo Experimental com mamona particulada acrescido de (BMP-HA); Grupo Experimental com mamona particulada acrescido de (BMP-HA), e estimulação laser (dose=178J/cm2; energia=1,4J). Os ratos foram sacrificados nos períodos de 15,45 e 60 dias; as mandíbulas foram removidas e processadas para inclusão em parafina, e os cortes de 6um foram corados por H&E, Tricrômico de Massom e Picro sirius. Os resultados histológicos mostraram formação óssea em todos os grupos. Nos grupos com o laser, a resposta tecidual foi antecipada em relação aos demais grupos promovendo a rápida neoformação da matriz óssea. / It suggest that polyurethane achieved from (Ricinus communis) induces bone repair because their osteoconductivity properties. In concerning the bone-inducing, that promotes osseous neoformation, it has been stimulate by growth factors, as bone morphogenetic protein (BMP), and laser therapy. The aim of this study was to evaluate osseous regeneration after mandible defects created in rats, and coveried with polyurethane resin partices (Ricinus communis), added with BMP and absorbable Hydroxyapatite (HA), stimulated or not by Laser beam. It was used the laser equipment Laser beam (Infra-red, continuous, Gallium-arsenide, 785nm, 35mW). Were utilized for this study 60 rats (Holtzman), were distributed in 4 groups of 15 animals. The control group (with only defect); the experimental group with laser stimulated (fluency=178J/cm2; energy=1,4J); the experimental group with resin particles added with (BMP-HA), and another similar group with laser stimulation (fluency=178J/cm2; energy=1,4J). The animals were then sacrified at the 15th, 45th and 60th days; mandibles were removed and processed for light microscopy. The histological examination samples were stain with H&E, Tricomic of Masson and Sirius Red. The results showed osseous neoformation in all groups. However, in the groups with laser stimulation the tissue response presented demonstrating earlier bone matrix formation.

Um dos mais importantes achados dos últimos anos foi o de que o remodelamento ósseo está sujeito ao controle do SNC, com o SNS agindo como efetor periférico. Um estudo do nosso grupo demonstrou que camundongos <font face=\"Symbol\">a2A/<font face=\"Symbol\">a2C-AR-/- apresentam um fenótipo de alta massa óssea, como também são resistentes à osteopenia induzida pelo excesso de hormônio HT. Com o intuito de verificar a participação do <font face=\"Symbol\">a2A-AR-/- nestes processos, tivemos como objetivos: caracterizar o fenótipo ósseo de camundongos <font face=\"Symbol\">a2A-AR-/- e avaliar o efeito do HT na estrutura óssea desses camundongos tratados. Pudemos observar que o comprimento longitudinal dos ossos dos animais <font face=\"Symbol\">a2A-AR-/- são menores do que dos animais selvagens e a análise por <font face=\"Symbol\">mCT do fêmur mostrou uma diminuição da porosidade da cortical. Com relação ao tratamento com hormônio tireoideano, os animais <font face=\"Symbol\">a2A-AR-/- tratados com T3 foram resistentes à diminuição do comprimento dos ossos causado pelo excesso de HT e vimos, ainda, que o osso trabecular dos animais <font face=\"Symbol\">a2A-AR-/- foi mais sensível aos efeitos deletérios da tirotoxicose, entretanto o osso cortical e parâmetros biomecânicos ósseos dos animais KOs foram menos sensíveis. Em conclusão, o presente estudo sugere que o <font face=\"Symbol\">a2A-AR está envolvido no processo de crescimento ósseo e que esse receptor possa mediar, pelo menos parcialmente, ações negativas do T3 nesse processo como também do HT no osso cortical. / One of the most important finds of the recent years is that bone remodeling is subject to the control of the CNS, with SNS acting as the peripheral effector. However, a recent study of our group showed that mice <font face=\"Symbol\">a2A/<font face=\"Symbol\">a2C-AR-/- have a high bone mass phenotype, even though are resistant to the thyroid hormone-induced osteopenia. In order to verify the role of <font face=\"Symbol\">a2A-AR-/- in these cases, we had as objectives to evaluate whether the isolated inactivation of <font face=\"Symbol\">a2A-AR interferes with the bone structure, and to evaluate the action of HT on these animals. We have observed that the longitudinal length of the bones of <font face=\"Symbol\">a2A-AR-/- animals are lower than those of wild type animals and the analysis of the femur by <font face=\"Symbol\">mCT showed a lower cortical porosity. With regard to treatment with thyroid hormone, we observed that <font face=\"Symbol\">a2A-AR-/- animals were resistant to the bone length decrease caused by thyroid hormone excess. We also noticed that the trabecular bone of <font face=\"Symbol\">a2A-AR-/- animals was more sensitive to the deleterious effects of thyrotoxicosis. Moreover, the cortical bone and bone biomechanical parameters KO animals were less sensitive. In conclusion, the findings of this study suggest that <font face=\"Symbol\">a2A-AR is involved in the process of bone growth and that this receptor may mediate at least partly, negative actions of T3 in this process as well as the HT in the cortical bone.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Este trabalho tem por objetivo avaliar mulheres portadoras de endometriose em uso de anÃlogos de GnRH investigando o metabolismo Ãsseo e massa Ãssea atravÃs da dosagem de marcadores sÃricos e realizaÃÃo de ultra-sonometria do calcÃneo, respectivamente. Trata-se de estudo observacional transversal tipo caso â controle prospectivo. Foi desenvolvido na Maternidade-Escola Assis Chateaubriand (MEAC) â UFC. Foram avaliadas 99 mulheres, divididas em 3 grupos, sendo 32 portadoras de endometriose diagnosticada cirurgicamente e tratadas com goserelina 3,6mg SC a cada 28 dias (4 doses) â grupo endometriÃtico. O segundo grupo foi composto de 25 mulheres nÃo endometriÃticas e no menacme (controle negativo). O terceiro grupo foi composto de 42 mulheres nÃo endometriÃticas e menopausadas por no mÃnimo dois anos, os dois Ãltimos grupos sem uso de medicaÃÃes. Foi realizada avaliaÃÃo Ãssea atravÃs da ultra-sonometria do calcÃneo com o aparelho Achilles, da LunarÂ, sendo determinado o âstiffnessâ de cada grupo (uma combinaÃÃo de velocidade do som e grau de atenuaÃÃo ultra-sonogrÃfica), juntamente com as dosagens sÃricas de magnÃsio, fosfato, urÃia, creatinina, cÃlcio, fosfatase alcalina (FA), PTH, cortisol e hidroxiprolina, alÃm das dosagens de cÃlcio urinÃrio, cÃlcio urinÃrio/creatinina, e hidroxiprolina/creatinina. O grupo endometriÃtico somente foi submetido a esta avaliaÃÃo apÃs o uso da medicaÃÃo. A anÃlise estatÃstica foi realizada pelo programa SPSS for Windows 11.0.0. As dosagens de FA, cÃlcio urinÃrio e cÃlcio urinÃrio/creatinina foram semelhantes no grupo endometriÃtico (40,8Â7,7U/mL; 47,15Â10,8mmol/L; e 78,76Â23,0, respectivamente) e no grupo menopausado (38,65Â5,1U/mL; 36,8Â4,3mmol/L; e 55,21Â8,21, respectivamente) alÃm de significativamente superiores aos do grupo no menacme (28,5Â2,54U/mL; 26,4Â3,4mmol/L; e 39,52Â7,7, respectivamente). As dosagens de PTH do grupo endometriÃtico (23,99Â3,35nmol/L) foram semelhantes as das mulheres no menacme (29,15Â4,09nmol/L), ambas sendo significativamente menores que as mulheres menopausadas (41,14Â3,7nmol/L). As demais anÃlises foram semelhantes entre os grupos. Na avaliaÃÃo Ãssea o âstiffnessâ foi similar entre o grupo endometriÃtico (88,16Â2,86) e as mulheres menopausadas (83,70Â1,8), sendo ambos significativamente inferiores Ãs mulheres no menacme (97,02Â1,46). Conclui-se que as portadoras de endometriose apÃs tratamento com goserelina apresentaram intenso metabolismo Ãsseo e piora no padrÃo do tecido Ãsseo avaliada pela ultra-sonometria do calcÃneo aproximando-se do quadro encontrado em mulheres menopausadas hà pelo menos dois anos. NÃo se pode afirmar, no entanto, se tais alteraÃÃes sÃo devidas exclusivamente ao uso do anÃlogo do GnRH ou somam-se à prÃpria manifestaÃÃo da endometriose. Sugere-se que a endometriose e o uso de anÃlogos do GnRH sejam considerados como fatores de risco para o desenvolvimento de osteoporose, principalmente se associados a uma histÃria de uso crÃnico de corticÃides a qualquer Ãpoca da vida. / This research had as an objective of evaluate endometriotic women treated with GnRH analogues by investigating their bone turnover and bone structure using serum bone turnover markers and calcaneous ultrasonometry, respectively. This is a transversal, observational, prospective caseâcontrol study. It was developed at Maternidade-Escola Assis Chateaubriand (MEAC) â UFC. Ninety nine women, divided into three groups were analyzed. Thirty two endometriotic women were treated with goserelin 3,6mg SC 28/28d (4 doses) â Endometriotic group. Their disease had been confirmed by surgery. The second group had twenty five non endometriotic women and having menses (control group). The third group had 42 not endometriotic menopausal women, they were at menopause at least for 2 years. The latest two groups were not taking any treatment. The Achilles device from Lunar, had being used to analyse the bone structure through calcaneous ultrasonometry. We calculated the âstiffnessâ value for each group (a combination of sound velocity and ultrasonographic attenuation), and we also analysed the values of magnesium, phosphate, urea, creatinine, serum calcium, alkaline phosphatase (ALP), parathyroid hormone (PTH), cortisol, hydroxyproline, urinary calcium, urinary calcium/creatinine, and hydroxyproline/creatinine. The endometriotic group was evaluated only after the treatment. The statistical analysis had being done by SPSS program for Windows version 11.0.0. The values of ALP, urinary calcium and urinary calcium/creatinine were similar to endometriotic group (40.8Â7.7U/mL; 47.15Â10.8mmol/L; and 78.76Â23.0, respectively) and to menopausal group (38.65Â5.1U/mL; 36.8Â4.3mmol/L; and 55.21Â8.21, respectively) although significantly higher than control group (28.5Â2.54U/mL; 26.4Â3.4mmol/L; and 39.52Â7.7, respectively). The values of PTH from endometriotic group (23.99Â3.35nmol/L) were similar to control group (29.15Â4.09nmol/L), and both were significantly lower than menopausal one (41.14Â3.7nmol/L). The other values were equal between groups. At the evaluation of bone âstiffnessâ the values were similar between endometriotic (88.16Â2.86) and menopausal groups (83.70Â1.8), and both were significantly lower than control group (97.02Â1.46). Concluding the endometriotic women who received treatment with goserelin showed an intense bone metabolism and a bone deficit at calcaneous ultrasonometry almost like women at post-menopausal at least two years. Therefore, we can not affirm if these alterations were caused exclusively by the GnRH-analogue therapy or were influenciated by endometriosis itself. We suggest that endometriosis and treatment with GnRH analogues might be considered as risks factors for the development of osteoporosis, principally if they are associated with chronic corticoid treatment at any point in a lifetime.

O hormônio da paratireóide (PTH) tem sido utilizado como um agente anabólico ósseo para o tratamento de condições de osteopenia / osteoporose, prevenção e consolidação de fraturas. O papel do fator de crescimento semelhante à insulina I (IGF-I), como um potencial mediador dos efeitos anabólicos do PTH, é controverso. O rato dwarf pode ser adequado para o estudo dessas interações in vivo, uma vez que a os níveis séricos de hormônio do crescimento (GH) encontram-se reduzidos a cerca de 6% dos valores normais em fêmeas e os níveis séricos de IGF-I, a cerca de 10% dos valores normais, mas estes animais são saudáveis e sem malformações esqueléticas. Os objetivos deste estudo foram: 1 - Avaliar o rato dwarf (dw-/dw-) como um modelo animal para o estudo dos efeitos da deficiência do GH e do IGF-I sobre o esqueleto e o metabolismo ósseo; 2 - Comparar os efeitos do tratamento com PTH sobre o esqueleto e formação óssea em ratos dwarf e em ratos Lewis, sua linhagem de origem. A partir de 9 semanas de idade, ratas Lewis e dwarf receberam injeções por via subcutânea, diariamente, por duas semanas, com medicamento placebo ou fragmento de hormônio paratireóideo humano, hPTH 1-34, na dose de 50 g / kg de peso corpóreo (N = 7-13/grupo). Foram realizadas avaliações do peso corpóreo semanalmente e, por ocasião da eutanásia, na 11ª semana, foram coletadas amostras de sangue para realização de dosagens séricas de IGF-I (ELISA). As vértebras lombares e as metáfises proximais das tíbias foram avaliadas por meio de histomorfometria óssea. Os fêmures direitos foram mensurados e analisados por tomografia quantitativa periférica computadorizada (pQCT). Os níveis séricos de IGF-I mostraram-se três vezes menores nas ratas dwarf quando comparados aos observados nas ratas Lewis, a despeito do tratamento com PTH, que não provocou aumento de IGF-I em nenhum dos dois grupos. No entanto, o PTH aumentou significativamente o volume ósseo trabecular em ambos os grupos, dwarf (p<0.003) e Lewis (p < 0.0001) comparados aos seus respectivos grupos controle, efeito associado ao aumento da espessura e da distância trabeculares. As ratas dwarf tratadas com PTH também exibiram aumentos de 7 a 13 vezes na superfície de mineralização e na taxa de formação óssea respectivamente, quando comparadas às ratas dwarf tratadas com placebo, enquanto as ratas Lewis tratadas com PTH mostraram aumentos de 3 e 4 vezes quando comparadas as ratas Lewis tratadas com placebo. A taxa de aposição mineral, indicativa de atividade osteoblástica, estava aumentada nas ratas dwarf e Lewis tratadas com PTH (p<0.0001) comparadas aos seus respectivos grupos controle. As análises pela pQCT das metáfises femorais distais revelaram que todos os parâmetros estruturais do osso trabecular (BMC total, BMD total, BMC trabecular e BMD trabecular) também apresentaram valores significativamente aumentados nas ratas, Lewis e dwarf, tratadas com PTH, quando comparadas às ratas tratadas com placebo (p<0.0001). Ao se considerar os parâmetros para o osso cortical, praticamente todos os valores obtidos nas diáfises femorais (BMC total, BMD total, BMC cortical, BMD cortical, área cortical, espessura cortical, circunferência periosteal e endosteal) não mostraram qualquer efeito do tratamento com PTH nos dois grupos. Em conclusão, o PTH induziu efeitos anabólicos altamente significativos no tecido ósseo trabecular das tíbias e vértebras lombares, a despeito dos baixos níveis circulantes de IGF-I em animais da linhagem dwarf. A resposta positiva ao tratamento com PTH confirma a sua utilização terapêutica como potente agente anabólico ósseo mesmo em face à deficiência no eixo GH/IGF-I / The parathyroid hormone (PTH) has been used as a bone anabolic agent to treat osteopenic/osteoporotic conditions, prevention and healing of fractures. The role of insulin-like growth factor I (IGF-I) as a potential mediator for the bone anabolic effects of PTH is controversial. The dwarf rat (dw-/dw-) may be suitable to study these interactions in vivo, since GH synthesis is selectively reduced to about 6% of normal in females, and serum IGF-I levels are about 10% of normal, but these animals are healthy without skeletal malformations. The objectives of this study were: 1- Evaluate the dwarf rat (dw-/dw-) as an animal model for studies of the effects of GH and IGF-I deficiency on the skeleton and bone metabolism; 2- Compare the skeletal effects of PTH treatment in dwarf rats and their background strain, Lewis rats. At 9 weeks of age, female Lewis and dwarf rats were injected SC daily for 2 weeks with vehicle or human parathyroid hormone fragment, hPTH 1-34, at a dose of 50 g/kg body weight (N=7- 13/group). The body weight was evaluated weekly and at the time of euthanasia, at 11 weeks, blood samples were collected. Serum IGF-I was measured by ELISA, and cancellous bone histomorphometry was performed in the lumbar vertebral body and tibial proximal metaphysis. The right femurs were measured, scanned and analyzed by peripheral quantitative computed tomography (pQCT). Serum levels of IGF-I were nearly 3-fold lower in dwarf rats compared with Lewis rats regardless of treatment, but PTH treatment did not increase serum IGF-I in either Lewis or dwarf rats. However, PTH significantly increased cancellous bone volume in both dwarf (P<0.003) and Lewis rats (P<0.0001) when compared to vehicle-treated rats, which was associated with increased trabecular width and decreased trabecular separation. PTH-treated dwarf rats also exhibited 7- and 13-fold increases in mineralizing surface and bone formation rate respectively, compared to vehicle-treated dwarf rats, while PTH-treated Lewis rats showed 3- and 4-fold increases when compared to vehicle-treated Lewis rats. Mineral apposition rate, an index of osteoblast activity, was increased in PTH-treated dwarf rats (P<0.0001) and in Lewis rats (P<0.0001) compared to their respective control groups. The pQCT analyses of the distal femoral metaphysis revealed that cancellous bone structural parameters (total BMC, total BMD, trabecular BMC, and trabecular BMD) also presented significantly higher values in PTH-treated dwarf and Lewis rats, when compared to vehicle treated rats (P<0.0001). When considering cortical bone parameters, almost all the values obtained at the femoral shafts (total BMC, total BMD, cortical BMC, cortical area, cortical thickness, periosteal and endocortical circumferences) did not show any PTH treatment effect in either groups. In conclusion, PTH induced highly significant anabolic effects in vertebral and tibial cancellous bone despite low circulating levels of IGF-I in dwarf rats. The positive response to PTH treatment confirms its therapeutic use as a potent bone anabolic agent, even in the face of GH/IGF-I deficiency

Abstract Osteoporosis is a bone disorder that leads to a reduction in bone volume, deterioration of bone microarchitecture and therefore increased fracture risk. Bone disorders such as osteoporosis commonly have both genetic and environmental components. Family and twin studies have shown the importance of genetics in bone formation and health, but most of the genetic factors contributing to bone formation are still largely unknown. The aim of this thesis was to search for and identify genetic factors that predispose to two different bone disorders manifesting in fractures, namely femoral neck stress fractures and childhood primary osteoporosis without features of OI (i.e. non-OI primary osteoporosis). Furthermore, in vitro studies were performed to elucidate the importance and mechanism of action of identified genetic factors in non-OI primary osteoporosis. By using candidate gene analyses we identified predisposing alleles, haplotypes and their interactions that increased the risk for femoral neck stress fractures in young male military conscripts. The conscripts lacking the CTR C allele and/or VDR C-A haplotype had a three-fold increased risk for femoral neck stress fractures compared to the carriers of both. Furthermore, conscripts carrying the LRP5 A-G-G-C haplotype had a three-fold increased risk for femoral neck stress fractures and in combination with VDR C-A haplotype a four-fold increased risk for stress fractures. These associations were mediated by low body weight and BMI. In the search for genetic factors of non-OI primary osteoporosis in children and adolescent, two novel mutations in LRP5 and two more variants in WNT3A and DKK1 were found in patients. The variants were also observed in the affected family members, but not in the control group. The effects of these variants were examined in in vitro studies and the results showed that some LRP5 mutations and the WNT3A variant might reduce bone formation by decreasing the canonical Wnt signalling activity. / Tiivistelmä Osteoporoosi on luustosairaus, joka alentaa luuntiheyttä ja heikentää luun rakennetta ja siten lisää murtumien riskiä. Osteoporoosin kaltaiset luusairaudet ovat usein monitekijäisiä tauteja, joiden syntyyn vaikuttavat sekä perinnölliset että ympäristölliset tekijät. Perhe- ja kaksostutkimukset ovat osoittaneet perinnöllisten tekijöiden olevan tärkeitä luun muodostuksessa ja terveydessä, mutta nämä tekijät ovat kuitenkin vielä suurelta osin tuntemattomia. Tutkimustyön tavoitteena oli etsiä ja tunnistaa perinnöllisiä tekijöitä, jotka altistavat kahdelle luunmurtumina ilmenevälle sairaudelle: reisiluunkaulan rasitusmurtumille ja lasten primaariselle osteoporoosille. Lisäksi primaariselle osteoporoosille altistavien perinnöllisten tekijöiden merkitystä ja vaikutusmekanismeja tutkittiin in vitro- kokeilla. Reisiluunkaulan rasitusmurtumille altistavien alleelien, haplotyyppien ja näiden vuorovaikutusten tunnistamiseen käytettiin ehdokasgeenianalyysiä nuorten alokkaiden aineistossa. Potilailla, joilta CTR-geenin C-alleeli ja/tai VDR-geenin C-A haplotyyppi puuttuivat, oli kolminkertainen riski rasitusmurtumien syntyyn molempien geenimuotojen kantajiin verrattuna. Myös LRP5-geenin A-G-G-C haplotyypin kantajilla oli kolminkertainen riski rasitusmurtumiin ja VDR-geenin C-A haplotyyppi ja A-G-G-C yhdessä lähes nelinkertaistivat rasitusmurtumien riskin alokkailla. Näiden assosiaatioiden todettiin välittyvän alhaisen painon ja painoindeksin välityksellä. Lapsuudessa tai varhaisnuoruudessa puhkeavan primaarisen osteoporoosin perinnöllisten tekijöiden etsinnässä löydettiin kaksi uutta mutaatiota LRP5-geenistä ja yhteensä kaksi uutta muutosta WNT3A- ja DKK1-geeneistä. Uusien ehdokasgeenilöydösten osuutta primaarisen osteoporoosin syntyyn tukee se, että muutokset löydettiin potilaiden lisäksi heidän sairailta sukulaisiltaan eikä muutoksia havaittu kontrolliaineistoissa. Uusien mutaatioiden mahdollisia vaikutuksia tutkittiin in vitro-kokein, jotka osoittivat, että eräät LRP5-geenin mutaatiot ja WNT3A-geenin muutos alentavat kanonisen Wnt-signalointireitin aktiivisuutta ja voivat siten vähentää luunmuodostusta.

O hormônio da paratireóide (PTH) tem sido utilizado como um agente anabólico ósseo para o tratamento de condições de osteopenia / osteoporose, prevenção e consolidação de fraturas. O papel do fator de crescimento semelhante à insulina I (IGF-I), como um potencial mediador dos efeitos anabólicos do PTH, é controverso. O rato dwarf pode ser adequado para o estudo dessas interações in vivo, uma vez que a os níveis séricos de hormônio do crescimento (GH) encontram-se reduzidos a cerca de 6% dos valores normais em fêmeas e os níveis séricos de IGF-I, a cerca de 10% dos valores normais, mas estes animais são saudáveis e sem malformações esqueléticas. Os objetivos deste estudo foram: 1 - Avaliar o rato dwarf (dw-/dw-) como um modelo animal para o estudo dos efeitos da deficiência do GH e do IGF-I sobre o esqueleto e o metabolismo ósseo; 2 - Comparar os efeitos do tratamento com PTH sobre o esqueleto e formação óssea em ratos dwarf e em ratos Lewis, sua linhagem de origem. A partir de 9 semanas de idade, ratas Lewis e dwarf receberam injeções por via subcutânea, diariamente, por duas semanas, com medicamento placebo ou fragmento de hormônio paratireóideo humano, hPTH 1-34, na dose de 50 g / kg de peso corpóreo (N = 7-13/grupo). Foram realizadas avaliações do peso corpóreo semanalmente e, por ocasião da eutanásia, na 11ª semana, foram coletadas amostras de sangue para realização de dosagens séricas de IGF-I (ELISA). As vértebras lombares e as metáfises proximais das tíbias foram avaliadas por meio de histomorfometria óssea. Os fêmures direitos foram mensurados e analisados por tomografia quantitativa periférica computadorizada (pQCT). Os níveis séricos de IGF-I mostraram-se três vezes menores nas ratas dwarf quando comparados aos observados nas ratas Lewis, a despeito do tratamento com PTH, que não provocou aumento de IGF-I em nenhum dos dois grupos. No entanto, o PTH aumentou significativamente o volume ósseo trabecular em ambos os grupos, dwarf (p<0.003) e Lewis (p < 0.0001) comparados aos seus respectivos grupos controle, efeito associado ao aumento da espessura e da distância trabeculares. As ratas dwarf tratadas com PTH também exibiram aumentos de 7 a 13 vezes na superfície de mineralização e na taxa de formação óssea respectivamente, quando comparadas às ratas dwarf tratadas com placebo, enquanto as ratas Lewis tratadas com PTH mostraram aumentos de 3 e 4 vezes quando comparadas as ratas Lewis tratadas com placebo. A taxa de aposição mineral, indicativa de atividade osteoblástica, estava aumentada nas ratas dwarf e Lewis tratadas com PTH (p<0.0001) comparadas aos seus respectivos grupos controle. As análises pela pQCT das metáfises femorais distais revelaram que todos os parâmetros estruturais do osso trabecular (BMC total, BMD total, BMC trabecular e BMD trabecular) também apresentaram valores significativamente aumentados nas ratas, Lewis e dwarf, tratadas com PTH, quando comparadas às ratas tratadas com placebo (p<0.0001). Ao se considerar os parâmetros para o osso cortical, praticamente todos os valores obtidos nas diáfises femorais (BMC total, BMD total, BMC cortical, BMD cortical, área cortical, espessura cortical, circunferência periosteal e endosteal) não mostraram qualquer efeito do tratamento com PTH nos dois grupos. Em conclusão, o PTH induziu efeitos anabólicos altamente significativos no tecido ósseo trabecular das tíbias e vértebras lombares, a despeito dos baixos níveis circulantes de IGF-I em animais da linhagem dwarf. A resposta positiva ao tratamento com PTH confirma a sua utilização terapêutica como potente agente anabólico ósseo mesmo em face à deficiência no eixo GH/IGF-I / The parathyroid hormone (PTH) has been used as a bone anabolic agent to treat osteopenic/osteoporotic conditions, prevention and healing of fractures. The role of insulin-like growth factor I (IGF-I) as a potential mediator for the bone anabolic effects of PTH is controversial. The dwarf rat (dw-/dw-) may be suitable to study these interactions in vivo, since GH synthesis is selectively reduced to about 6% of normal in females, and serum IGF-I levels are about 10% of normal, but these animals are healthy without skeletal malformations. The objectives of this study were: 1- Evaluate the dwarf rat (dw-/dw-) as an animal model for studies of the effects of GH and IGF-I deficiency on the skeleton and bone metabolism; 2- Compare the skeletal effects of PTH treatment in dwarf rats and their background strain, Lewis rats. At 9 weeks of age, female Lewis and dwarf rats were injected SC daily for 2 weeks with vehicle or human parathyroid hormone fragment, hPTH 1-34, at a dose of 50 g/kg body weight (N=7- 13/group). The body weight was evaluated weekly and at the time of euthanasia, at 11 weeks, blood samples were collected. Serum IGF-I was measured by ELISA, and cancellous bone histomorphometry was performed in the lumbar vertebral body and tibial proximal metaphysis. The right femurs were measured, scanned and analyzed by peripheral quantitative computed tomography (pQCT). Serum levels of IGF-I were nearly 3-fold lower in dwarf rats compared with Lewis rats regardless of treatment, but PTH treatment did not increase serum IGF-I in either Lewis or dwarf rats. However, PTH significantly increased cancellous bone volume in both dwarf (P<0.003) and Lewis rats (P<0.0001) when compared to vehicle-treated rats, which was associated with increased trabecular width and decreased trabecular separation. PTH-treated dwarf rats also exhibited 7- and 13-fold increases in mineralizing surface and bone formation rate respectively, compared to vehicle-treated dwarf rats, while PTH-treated Lewis rats showed 3- and 4-fold increases when compared to vehicle-treated Lewis rats. Mineral apposition rate, an index of osteoblast activity, was increased in PTH-treated dwarf rats (P<0.0001) and in Lewis rats (P<0.0001) compared to their respective control groups. The pQCT analyses of the distal femoral metaphysis revealed that cancellous bone structural parameters (total BMC, total BMD, trabecular BMC, and trabecular BMD) also presented significantly higher values in PTH-treated dwarf and Lewis rats, when compared to vehicle treated rats (P<0.0001). When considering cortical bone parameters, almost all the values obtained at the femoral shafts (total BMC, total BMD, cortical BMC, cortical area, cortical thickness, periosteal and endocortical circumferences) did not show any PTH treatment effect in either groups. In conclusion, PTH induced highly significant anabolic effects in vertebral and tibial cancellous bone despite low circulating levels of IGF-I in dwarf rats. The positive response to PTH treatment confirms its therapeutic use as a potent bone anabolic agent, even in the face of GH/IGF-I deficiency

Over 600,000 bone-grafting operations are performed each year in the United States. The majority of the bone used for these surgeries comes from autografts that are limited in quantity or allografts with high failure rates. Current synthetic bone grafting materials have poor mechanical properties, handling characteristics, and bioactivity. The goal of this dissertation was to develop a clinically translatable bone tissue engineering scaffold with improved handling characteristics, bioactivity, and smart delivery modalities. We hypothesized that this could be achieved through the rational selection of Food and Drug Administration (FDA) approved materials that blend favorably with hydroxyapatite (HA), the principle mineral component in bone. This dissertation describes the development of smart bone tissue engineering scaffolds composed of the biodegradable amphiphilic polymer poly(D,L-lactic acid-co-ethylene glycol-co- D,L-lactic acid) (PELA) and HA. Electrospun nanofibrous HA-PELA scaffolds exhibited improved handling characteristics and bioactivity over conventional HApoly( D,L-lactic acid) composites. Electrospun HA-PELA was hydrophilic, elastic, stiffened upon hydration, and supported the attachment and osteogenic differentiation of rat bone marrow stromal cells (MSCs). These in vitro properties translated into robust bone formation in vivo using a critical-size femoral defect model in rats. Spiral-wrapped HA-PELA scaffolds, loaded with MSCs or a lowdose of recombinant human bone morphogenetic protein-2, templated bone formation along the defect. As an alternate approach, PELA and HA-PELA were viii rapid prototyped into three-dimensional (3-D) macroporous scaffolds using a consumer-grade 3-D printer. These 3-D scaffolds have differential cell adhesion characteristics, swell and stiffen upon hydration, and exhibit hydration-induced self-fixation in a simulated confined defect. HA-PELA also exhibits thermal shape memory behavior, enabling the minimally invasive delivery and rapid (>3 sec) shape recovery of 3-D scaffolds at physiologically safe temperatures (~ 50ºC). Overall, this dissertation demonstrates how the rational selection of FDA approved materials with synergistic interactions results in smart biomaterials with high potential for clinical translation.

Recent advances in the methods of skeletal age estimation have rekindled interest in their applicability to paleodemography. The current study contributes to the discussion by applying several long established as well as recently developed or refined aging methods to a subsample of 121 adult skeletons from the early medieval cemetery of Lauchheim. The skeletal remains were analyzed by 13 independent observers using a variety of aging techniques (complex method and other multimethod approaches, Transition Analysis, cranial suture closure, auricular surface method, osteon density method, tooth root translucency measurement, and tooth cementum annulation counting). The age ranges and mean age estimations were compared and results indicate that all methods showed smaller age ranges for the younger individuals, but broader age ranges for the older age groups.

Les phosphates de calcium sont des biomatériaux couramment utilisés dans de nombreuses spécialités médicales. L'amélioration de ces biomatériaux vise à augmenter leur ostéointégration et leur bioactivité. Le strontium possédant d'intéressantes capacités de modification de la physiologie osseuse, l'incorporation de ce dernier au sein de phosphates de calcium par substitution ionique pourrait permettre un déplacement de la balance osseuse vers la formation osseuse.Notre travail a permis de démontrer la capacité des particules de phosphates de calcium substitués en strontium à augmenter la prolifération des ostéoblastes en culture et à modifier l'expression et la synthèse des principales protéines impliquées dans la physiologie osseuse (Collagène de type I, Serpine H1, métalloprotéinases matricielles 1 et 2, inhibiteurs tissulaires des MMPs). Par ailleurs, la poudre de phosphates de calcium ne contenant pas de strontium a entrainé une sécrétion accrue de chimiokines pro-inflammatoires (MCP-1 et GRO-?) qui n'a pas été observée pour la poudre substituée. Enfin, des études in-vivo réalisées dans un modèle de défaut osseux murin a permis de démontrer une plus grande résorbabilité de la poudre contenant du strontium et sa plus grande capacité à stimuler la réparation osseuse. / Calcium phosphate are widely used in medicine. Their upgrade tend to enhance their biocompatibility and their bioactivity. Strontium has interesting capability to modify the bone physiologie. Its incorporation in calcium phosphates could lead to modify the bone balance toward osteogenesis.The present work reveal the capacities of such biomaterials to enhance the replication of osteoblasts ant to modify the expression and the synthesis of proteins implicated in the bone balance (type I collagen, serpinH1, Matrix metalloproteinases 1 and 2, tissular inhibitors of MMPs). Moreover, non substituted calcium phosphate powders enhance the expression and synthesis of inflammatory cytokines (MCP-1 and Gro-a). This fact was not observed with the non substituted powder. In-vivo studies on a mouse model permit us to demonstrate the higher resorbability and the higher bone healing capability of the substituted powder.

INTRODUÇÃO: A síndrome de Kabuki (SK) é uma doença genética de etiologia desconhecida, cujas características cardinais são: dismorfismos faciais, baixa estatura de inicio pós-natal, anomalias esqueléticas, déficit cognitivo e alteração de dermatóglifos. Já foram descritas alterações em outros órgãos e sistemas. O diagnóstico é clínico. OBJETIVOS: Descrever os achados clínicos, e a evolução clínica de pacientes com SK. CASUÍSTICA E METODOLOGIA: Foram estudados 12 pacientes, oito do sexo feminino e quatro do sexo masculino, onde foram realizados: anamnese, exame físico, revisão de prontuário, avaliação cardiológica e odontológica, exames de imagem e laboratoriais. RESULTADOS: Todos pacientes tinham: face típica, déficit cognitivo, alterações esqueléticas e persistência de padrão fetal em coxins digitais. As alterações esqueléticas mais freqüentes foram: braquidactilia do quinto dedo, frouxidão ligamentar e luxação de quadril. A baixa estatura foi encontrada em 8/12 pacientes. Oito apresentavam ausência de dentes. Alterações oftalmológicas foram identificadas em sete. Na avaliação da audição, três tinham otites e dois, perda auditiva. Cinco pacientes apresentaram doenças respiratórias. Três pacientes apresentavam cardiopatias, e uma tinha somente alteração eletrocardiográfica. Seis pacientes tiveram dificuldades alimentares nos primeiros anos de vida e cinco, refluxo gastroesofágico. Três pacientes tinham anomalias renais, dois apresentaram enurese noturna e dois criptorquidia. Hipotonia estava presente em cinco pacientes e convulsões em quatro. Hipotireoidismo estava presente em duas pacientes e uma paciente tinha deficiência de hormônio de crescimento. Dois pacientes relataram um episódio de púrpura trombocitopênica. Alterações imunológicas foram identificadas em três pacientes. Anomalias do cromossomo X foram identificadas em duas pacientes. Nenhum paciente faleceu durante o estudo. Dos pacientes com mais de 18 anos, 3/4 tinham baixa estatura e nos pacientes com mais de 10 anos 4/7 tornaram-se obesos. DISCUSSÃO: A maioria de nossos achados foi compatível com a encontrada na literatura. As pacientes com alterações no cromossomo X, apresentavam características de SK e síndrome de Turner, não podendo descartar ou confirmar a coexistência destas duas doenças. CONCLUSÕES: a SK apresenta uma grande variabilidade clínica, devendo seus portadores, ter suporte multidisciplinar. As anomalias renais, cardíacas, imunológicas e esqueléticas, foram responsáveis pelas principais complicações clínicas relatadas / INTRODUCTION: Kabuki syndrome (KS) is a genetic disease which cardinal manifestations are: facial dysmorfism, short stature of postnatal onset, skeletal abnormalities, mental retardation and abnormal dermatolyphics. Beside these manifestations, abnormalities of every organ system, has been described. The diagnosis is clinical. OBJECTIVES: The objective is to describe the clinical manifestations and the follow-up of patients with Kabuki syndrome. PATIENTS AND METHODS: Twelve patients were studied, eight female and four male, not related, in which anamnesis, physical examination, review of their clinical records, odontological and ophthalmological evaluation, radiological and laboratorial tests, were performed. RESULTS: All patients have: typical face, mental retardation, skeletal abnormalities and presence of fingertip pads. Short stature was present in 8/12 patients. The most frequent skeletal abnormalities were: short fingers, hypotony and hip dislocation. Eight patients have absence of teeth. Ophthalmologic abnormalities were found in seven patients. On hearing evaluation, three patients have recurrent otitis and hearing lost was identified in two patients. Apnea and laryngo malacia was present in one patient. Three patients presented congenital cardiopathy and one patient without cardiopathy had an anomaly at electrocardiography. At the first years of life, six patients had feeding difficulties, with one whom needed a gastrostomy tube and five had gastroesofageal reflux. A kidney and urinary tract malformation was found in three patients, two had nocturnal enuresis, and two had undescended testis. Hypotonia was present in five patients and four reported seizures. Hypothyroidism was present in two patients and one had growth hormone deficiency. Two patients had an episode of thrombocytopenic purpura. Immunologic abnormalities were identified in three patients. Cytogenetic abnormalities of X chromosome were identified in two female patients. During the study, no one patient died. In adult patients, 3/4 had short stature, and, in patients with 10 years or more, 4/7 were obese. DISCUSSION: Most of our findings were compatible with the literature. The patients with X chromosome abnormalities presented characteristics of KS and Turners syndrome and we are not able to make an exact distinction if they have or not both diseases. CONCLUSION: KS has a wide clinical variability and the affected ones should be followed by a multidisciplinary clinic. Renal, cardiac, skeletal and immunological abnormalities are those with most morbidity related by the patients