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1.
J Anal Toxicol ; 39(8): 655-61, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26378141

RESUMO

Interpretation of opiate drug test results can be challenging due to casual dietary consumption of poppy seeds, which may contain variable opiate content. Opiate concentrations in paired oral fluid (OF), collected with the Oral-Eze(®) Oral Fluid Collection System, and urine were analyzed after ingestion of poppy seeds from the same source, consumed raw or contained in a roll. In Part 1, 12 individuals consumed equal portions of a poppy seed roll. For Part 2, the same individuals consumed an equivalent quantity of raw poppy seeds, containing ∼3.2 mg of morphine and 0.6 mg of codeine. Specimens were analyzed both by enzyme immunoassay (opiates) and by GC-MS (morphine/codeine). Urinary morphine was between 155-1,408 (roll) and 294-4,213 ng/mL (raw), measured at 2, 4, 6 and 20 h post-ingestion. Urinary codeine concentrations between 140-194 (roll) and 121-664 ng/mL (raw) were observed up to 6 h post-ingestion. Following consumption of raw poppy seeds, OF specimens were positive, above LOQ, from 0.25 to 3.0 h with morphine ranging from 7 to 600 ng/mL and codeine from 8 to 112 ng/mL. After poppy seed roll consumption, morphine concentrations of 7-143 ng/mL were observed up to 1.5 h with codeine detected in only 5.5% of OF specimens and ranging from 8 to 28 ng/mL. Combined with the existing poppy seed literature, these results support previous findings and provide guidance for interpretation of OF opiate testing.


Assuntos
Codeína/análise , Morfina/análise , Papaver , Saliva/química , Adulto , Codeína/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Morfina/urina , Sementes
2.
Bonekey Rep ; 4: 664, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25908967

RESUMO

As in clinical studies, finite element analysis (FEA) developed from computed tomography (CT) images of bones are useful in pre-clinical rodent studies assessing treatment effects on vertebral body (VB) strength. Since strength predictions from microCT-derived FEAs (µFEA) have not been validated against experimental measurements of mouse VB strength, a parametric analysis exploring material and failure definitions was performed to determine whether elastic µFEAs with linear failure criteria could reasonably assess VB strength in two studies, treatment and genetic, with differences in bone volume fraction between the control and the experimental groups. VBs were scanned with a 12-µm voxel size, and voxels were directly converted to 8-node, hexahedral elements. The coefficient of determination or R (2) between predicted VB strength and experimental VB strength, as determined from compression tests, was 62.3% for the treatment study and 85.3% for the genetic study when using a homogenous tissue modulus (E t) of 18 GPa for all elements, a failure volume of 2%, and an equivalent failure strain of 0.007. The difference between prediction and measurement (that is, error) increased when lowering the failure volume to 0.1% or increasing it to 4%. Using inhomogeneous tissue density-specific moduli improved the R (2) between predicted and experimental strength when compared with uniform E t=18 GPa. Also, the optimum failure volume is higher for the inhomogeneous than for the homogeneous material definition. Regardless of model assumptions, µFEA can assess differences in murine VB strength between experimental groups when the expected difference in strength is at least 20%.

3.
Bone ; 62: 1-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24509412

RESUMO

Even though age-related changes to bone tissue affecting fracture risk are well characterized, only a few matrix-related factors have been identified as important to maintaining fracture resistance. As a gene critical to osteoblast differentiation, activating transcription factor 4 (ATF4) is possibly one of these important factors. To test the hypothesis that the loss of ATF4 affects the fracture resistance of bone beyond bone mass and structure, we harvested bones from Atf4+/+ and Atf4-/- littermates at 8 and 20 weeks of age (n≥9 per group) for bone assessment across several length scales. From whole bone mechanical tests in bending, femurs from Atf4-/- mice were found to be brittle with reduced toughness and fracture toughness compared to femurs from Atf4+/+ mice. However, there were no differences in material strength and in tissue hardness, as determined by nanoindentation, between the genotypes, irrespective of age. Tissue mineral density of the cortex at the point of loading as determined by micro-computed tomography was also not significantly different. However, by analyzing local composition by Raman Spectroscopy (RS), bone tissue of Atf4-/- mice was found to have higher mineral to collagen ratio compared to wild-type tissue, primarily at 20 weeks of age. From RS analysis of intact femurs at 2 orthogonal orientations relative to the polarization axis of the laser, we also found that the organizational-sensitive peak ratio, ν1Phosphate per Amide I, changed to a greater extent upon bone rotation for Atf4-deficient tissue, implying bone matrix organization may contribute to the brittleness phenotype. Target genes of ATF4 activity are not only important to osteoblast differentiation but also in maintaining bone toughness and fracture toughness.


Assuntos
Fator 4 Ativador da Transcrição/deficiência , Osso e Ossos/metabolismo , Osso e Ossos/fisiopatologia , Fraturas Ósseas/metabolismo , Fraturas Ósseas/fisiopatologia , Fator 4 Ativador da Transcrição/metabolismo , Animais , Matriz Óssea/patologia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Calcificação Fisiológica , Força Compressiva , Fêmur/diagnóstico por imagem , Fêmur/patologia , Fêmur/fisiopatologia , Fraturas Ósseas/diagnóstico por imagem , Deleção de Genes , Modelos Lineares , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Vértebras Lombares/fisiopatologia , Camundongos , Especificidade de Órgãos , Fatores de Tempo , Microtomografia por Raio-X
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