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Registro Completo |
Biblioteca(s): |
Embrapa Gado de Corte. |
Data corrente: |
29/10/1998 |
Data da última atualização: |
15/01/2014 |
Autoria: |
NICODEMO, M. L. F. |
Afiliação: |
EMBRAPA. Centro Nacional de Pesquisa de Gado de Corte (Campo Grande, MS). |
Título: |
Measurement and function of turnover markers in sheep and pig bone. |
Ano de publicação: |
1997 |
Fonte/Imprenta: |
[S.l.] : University of Aberdeen, 1997. |
Páginas: |
204p. |
Idioma: |
Inglês |
Notas: |
Tese Doutorado. CNPGC. |
Conteúdo: |
Plasma osteocalcin and the urinary pyridinium crosslinks, pyridinoline and deoxypyridinoline are widely used as markers of bone tumover though many aspects of their function and metabolism remain obscure. In this thesis several likely physiological determinants of the levels of these markers in blood, bone and urine were examined in sheep and in pigs. Measurement of osteocalcin proved a major problem, immunoassay being unreliable as a method for measuring the levels of this protein in bone. This necessitated the development of an RP-HPLC assay (Chapter 3) in which the protein was separated from bone extracts using a linear 4-60% acetonitrile gradient containing 0. I % TFA run over 45 mins at a flow rate of lml/min. The standard curve was linear over a range of 0.5-15.0 pg osteocalcin injected and with inter- and intra-assay coefficients of variation of 6.9 and 8.8 §lo respectively and with recovery of osteocalcin added to bone extracts averaging 102.7+ 6,16 %. In sheep, plasma osteocalcin levels, determined by ELISA, showed large between animal as well as variability over 24 hours but no evidence of consistent circadian rhythm and decreased with age. In bone, changes in osteocalcin level tended to parallel those for calcium, whereas levels of the pyridinium crosslinks tended to increase with age (Chapter 4). Neither group of markers were sufficiently sensitive to detect differences in bone tumover between lambs of similar age but growing at different rates (Chapter 5). At slaughter the faster growing lambs had heavier though less well mineralised bones but showed no change in the ratio of calcium/osteocalcin. The ratio of calcium/osteocalcin in bone was also unchanged in lambs fed diets deficient in phosphorus (Chapter 6) despite an overall decline in mineral and in plasma and bone osteocalcin contents, which appeared to support the view that plasma and bone osteocalcin contents, which appeared to support the view thatosteocalcin may play a functional role in the mineralization process. However, against this, pigs fed diets deficient in both calcium and phosphorus showed no change in either plasma or bone osteocalcin levels despite marked reductions in bone calcium content (Chapter 7). This suggests that the amount of osteocalcin deposited in bone is not simply related to the amount of mineral present and so calls into question whether it has a direct role in the mineralization process. Chapter 8 describes an experiment in which adult sheep were treated with one of the new bisphosphonates (Ibandronate) and its effects on the metabolism of both pyridinoline and deoxypyridinoline were monitored. Given at rates which have been shown to be effective in reducing bone resorption in humans, this compound had little effect on the overall rates of excretion of these crosslinks but did alter the proportions excreted in free or peptide bound form. Another feature of this study was the high variability seen in the escretion of these markers in urine both between animals and between collection periods with coeficients of variation of 48 and 36 % for total pyridinoline and deoxypyridinoline and 62 and 50 % for their free fractions. Similar high variability has been reported by other workers and has clear implications in regard to the accuracy of the these markers. MenosPlasma osteocalcin and the urinary pyridinium crosslinks, pyridinoline and deoxypyridinoline are widely used as markers of bone tumover though many aspects of their function and metabolism remain obscure. In this thesis several likely physiological determinants of the levels of these markers in blood, bone and urine were examined in sheep and in pigs. Measurement of osteocalcin proved a major problem, immunoassay being unreliable as a method for measuring the levels of this protein in bone. This necessitated the development of an RP-HPLC assay (Chapter 3) in which the protein was separated from bone extracts using a linear 4-60% acetonitrile gradient containing 0. I % TFA run over 45 mins at a flow rate of lml/min. The standard curve was linear over a range of 0.5-15.0 pg osteocalcin injected and with inter- and intra-assay coefficients of variation of 6.9 and 8.8 §lo respectively and with recovery of osteocalcin added to bone extracts averaging 102.7+ 6,16 %. In sheep, plasma osteocalcin levels, determined by ELISA, showed large between animal as well as variability over 24 hours but no evidence of consistent circadian rhythm and decreased with age. In bone, changes in osteocalcin level tended to parallel those for calcium, whereas levels of the pyridinium crosslinks tended to increase with age (Chapter 4). Neither group of markers were sufficiently sensitive to detect differences in bone tumover between lambs of similar age but growing at different rates (Chapter 5). At sl... Mostrar Tudo |
Palavras-Chave: |
Biochemical markers; Bone markers; Deoxypiridinoline; Diagnosis; Dioxidipirionolina; Marcador bioquimico; Marcador osseo; Metabolismo osseo; Osteocalcina; Ovine; Piridinolina; Pyridinoline. |
Thesagro: |
Diagnostico; Fisiologia; Osso; Ovino; Suíno. |
Thesaurus Nal: |
bone metabolism; bones; osteocalcin; physiology; swine. |
Categoria do assunto: |
-- |
Marc: |
LEADER 04307nam a2200397 a 4500 001 1319734 005 2014-01-15 008 1997 bl uuuu m 00u1 u #d 100 1 $aNICODEMO, M. L. F. 245 $aMeasurement and function of turnover markers in sheep and pig bone. 260 $a[S.l.] : University of Aberdeen$c1997 300 $a204p. 500 $aTese Doutorado. CNPGC. 520 $aPlasma osteocalcin and the urinary pyridinium crosslinks, pyridinoline and deoxypyridinoline are widely used as markers of bone tumover though many aspects of their function and metabolism remain obscure. In this thesis several likely physiological determinants of the levels of these markers in blood, bone and urine were examined in sheep and in pigs. Measurement of osteocalcin proved a major problem, immunoassay being unreliable as a method for measuring the levels of this protein in bone. This necessitated the development of an RP-HPLC assay (Chapter 3) in which the protein was separated from bone extracts using a linear 4-60% acetonitrile gradient containing 0. I % TFA run over 45 mins at a flow rate of lml/min. The standard curve was linear over a range of 0.5-15.0 pg osteocalcin injected and with inter- and intra-assay coefficients of variation of 6.9 and 8.8 §lo respectively and with recovery of osteocalcin added to bone extracts averaging 102.7+ 6,16 %. In sheep, plasma osteocalcin levels, determined by ELISA, showed large between animal as well as variability over 24 hours but no evidence of consistent circadian rhythm and decreased with age. In bone, changes in osteocalcin level tended to parallel those for calcium, whereas levels of the pyridinium crosslinks tended to increase with age (Chapter 4). Neither group of markers were sufficiently sensitive to detect differences in bone tumover between lambs of similar age but growing at different rates (Chapter 5). At slaughter the faster growing lambs had heavier though less well mineralised bones but showed no change in the ratio of calcium/osteocalcin. The ratio of calcium/osteocalcin in bone was also unchanged in lambs fed diets deficient in phosphorus (Chapter 6) despite an overall decline in mineral and in plasma and bone osteocalcin contents, which appeared to support the view that plasma and bone osteocalcin contents, which appeared to support the view thatosteocalcin may play a functional role in the mineralization process. However, against this, pigs fed diets deficient in both calcium and phosphorus showed no change in either plasma or bone osteocalcin levels despite marked reductions in bone calcium content (Chapter 7). This suggests that the amount of osteocalcin deposited in bone is not simply related to the amount of mineral present and so calls into question whether it has a direct role in the mineralization process. Chapter 8 describes an experiment in which adult sheep were treated with one of the new bisphosphonates (Ibandronate) and its effects on the metabolism of both pyridinoline and deoxypyridinoline were monitored. Given at rates which have been shown to be effective in reducing bone resorption in humans, this compound had little effect on the overall rates of excretion of these crosslinks but did alter the proportions excreted in free or peptide bound form. Another feature of this study was the high variability seen in the escretion of these markers in urine both between animals and between collection periods with coeficients of variation of 48 and 36 % for total pyridinoline and deoxypyridinoline and 62 and 50 % for their free fractions. Similar high variability has been reported by other workers and has clear implications in regard to the accuracy of the these markers. 650 $abone metabolism 650 $abones 650 $aosteocalcin 650 $aphysiology 650 $aswine 650 $aDiagnostico 650 $aFisiologia 650 $aOsso 650 $aOvino 650 $aSuíno 653 $aBiochemical markers 653 $aBone markers 653 $aDeoxypiridinoline 653 $aDiagnosis 653 $aDioxidipirionolina 653 $aMarcador bioquimico 653 $aMarcador osseo 653 $aMetabolismo osseo 653 $aOsteocalcina 653 $aOvine 653 $aPiridinolina 653 $aPyridinoline
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Embrapa Gado de Corte (CNPGC) |
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Registro Completo
Biblioteca(s): |
Embrapa Amazônia Oriental. |
Data corrente: |
27/02/2013 |
Data da última atualização: |
09/11/2022 |
Tipo da produção científica: |
Resumo em Anais de Congresso |
Autoria: |
CAVALCANTE, M. C.; FREITAS, B. M.; MAUES, M. M. |
Afiliação: |
MARCELO CASIMIRO CAVALCANTE, UFC; BRENO MAGALHÃES FREITAS, UFC; MARCIA MOTTA MAUES, CPATU. |
Título: |
Surrounding's effect on the pollinators community of Bertholletia excels in a plantation at Central Amazon rain forest. |
Ano de publicação: |
2012 |
Fonte/Imprenta: |
In: ENCONTRO SOBRE ABELHAS, 10., 2012, Ribeirão Preto. Anais... Ribeirão Preto: FUNPEC, 2012. |
Páginas: |
p. 167. |
Idioma: |
Inglês |
Palavras-Chave: |
Abundance; Layout; Richness; Secondary vegetation. |
Thesagro: |
Polinização; Vegetação Secundária. |
Thesaurus NAL: |
Amazonia; pollination. |
Categoria do assunto: |
-- |
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/77566/1/p167.pdf
|
Marc: |
LEADER 00744nam a2200229 a 4500 001 1951549 005 2022-11-09 008 2012 bl uuuu u00u1 u #d 100 1 $aCAVALCANTE, M. C. 245 $aSurrounding's effect on the pollinators community of Bertholletia excels in a plantation at Central Amazon rain forest.$h[electronic resource] 260 $aIn: ENCONTRO SOBRE ABELHAS, 10., 2012, Ribeirão Preto. Anais... Ribeirão Preto: FUNPEC$c2012 300 $ap. 167. 650 $aAmazonia 650 $apollination 650 $aPolinização 650 $aVegetação Secundária 653 $aAbundance 653 $aLayout 653 $aRichness 653 $aSecondary vegetation 700 1 $aFREITAS, B. M. 700 1 $aMAUES, M. M.
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