The absence of ABCA1 decreases soluble ApoE levels but does not diminish amyloid deposition in two murine models of Alzheimer disease.

J Biol Chem. 2005 Dec 30;280(52):43243-56. Epub 2005 Oct 5. The absence of ABCA1 decreases soluble ApoE levels but does not diminish amyloid deposition in two murine models of Alzheimer disease. Hirsch-Reinshagen V, Maia LF, Burgess BL, Blain JF, Naus KE, McIsaac SA, Parkinson PF, Chan JY, Tansley GH, Hayden MR, Poirier J, Van Nostrand W, Wellington CL. Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V4Z 5H5, Canada. Abstract ABCA1, a cholesterol transporter expressed in the brain, has been shown recently to be required to maintain normal apoE levels and lipidation in the central nervous system. In addition, ABCA1 has been reported to modulate beta-amyloid (Abeta) production in vitro. These observations raise the possibility that ABCA1 may play a role in the pathogenesis of Alzheimer disease. Here we report that the deficiency of ABCA1 does not affect soluble or guanidine-extractable Abeta levels in Tg-SwDI/B or amyloid precursor protein/presenilin 1 (APP/PS1) mice, but rather is associated with a dramatic reduction in soluble apoE levels in brain. Although this reduction in apoE was expected to reduce the amyloid burden in vivo, we observed that the parenchymal and vascular amyloid load was increased in Tg-SwDI/B animals and was not diminished in APP/PS1 mice. Furthermore, we observed an increase in the proportion of apoE retained in the insoluble fraction, particularly in the APP/PS1 model. These data suggested that ABCA1-mediated effects on apoE levels and lipidation influenced amyloidogenesis in vivo. PMID: 16207707 [PubMed - indexed for MEDLINE

RAPD Variation in the Rare and Endangered Leucadendron Elimense (Proteaceae): Implications for Their Conservation.

We measured genetic variation of the three rare sub-species of the cone bush, Leucadendron elimense (Proteaceae), in comparison with a widespread, common species, Leucadendron salignum, using randomly amplified polymorphic DNA (RAPDs). Despite small population sizes and restricted distributions, study populations of L. elimense showed high levels of genetic variation in all three sub-species (0.24–0.34) with a genetic variation of 0.35 for the species as a whole. This was slightly higher than that measured for L. salignum (0.30), the most ubiquitous species of Leucadendron in the Cape flora. Analysis of molecular variance (AMOVA) indicated that most of the genetic variation lay among individuals within populations. We suggest several mechanisms whereby high levels of genetic variation might persist in small, isolated populations of rare Cape Proteaceae and propose that such taxa can be protected in a series of very small reserves at relatively low cost and minimal management input

Gallium and oxygen accumulations on gallium nitride surfaces following argon ion milling in ultra-high vacuum conditions

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Genetic variability of Pantaneiro horse using RAPD-PCR markers Variabilidade genética do cavalo Pantaneiro utilizando marcadores RAPD-PCR

Blood samples were collected from Pantaneiro Horses in five regions of Mato Grosso do Sul and Mato Grosso States. Arabian, Mangalarga Marchador and Thoroughbred were also included to estimate genetic distances and the existing variability among and within these breeds by RAPD-PCR (Random Amplified Polymorphic DNA - Polymerase Chain Reaction) molecular markers. From 146 primers, 13 were chosen for amplification and 44 polymorphic bands were generated. The analysis of molecular variance (AMOVA) indicated that the greatest portion of detected variability was due to differences between individuals within populations (75.47%). Analysis of the genetic variability between pairs of populations presented higher estimates for the five Pantaneiro populations with the Arabian breed, while lowest estimates were presented by pairs formed among the Pantaneiro populations with the Mangalarga Marchador. Highest genic diversity was shown by the Pantaneiro (0.3396), which also showed highest genetic distance with the Arabian and lowest with Mangalarga Marchador breed. UPGMA dendrogram showed distinct differences between naturalized (Pantaneiro and Mangalarga Marchador) and exotic (Arabian and Thoroughbred) breeds. In the dendrogram generated by UPGMA method, the similarity matrix generated by the Jaccard coefficient showed distinction between the naturalised breeds, Pantaneiro and Mangalarga Marchador, and the exotic breeds, Árab and English Thoroughbred. Results suggest that the Pantaneiro presents a higher genetic variability than the other studied breeds and has a close relationship with the Mangalarga Marchador.<br>Amostras de sangue foram coletadas de cavalos Pantaneiros de cinco regiões dos estados de Mato Grosso do Sul e Mato Grosso. As raças Mangalarga Marchador, Árabe e Puro-Sangue Inglês (PSI) usando marcadores moleculares RAPD-PCR (Random Amplified Polymorphic DNA - Polymerase Chain Reaction) foram incluídas no intuito de se calcular as distâncias genéticas e comparar a variabilidade genética entre e dentro de cada uma das raças. Dos 146 primers escrutinados, 13 foram escolhidos para amplificação com cada um dos indivíduos das oito populações, gerando um total de 44 bandas polimórficas. Os resultados encontrados na Análise de Variância Molecular (AMOVA) indicam que grande parte da variabilidade genética detectada se deve a diferenças entre indivíduos dentro de populações (75,47%). Na análise da estimativa dos percentuais de variabilidade genética entre pares de populações, foram observados maiores valores para os pares formados entre as cinco populações de cavalo Pantaneiro e a raça Árabe, enquanto os menores percentuais ocorreram entre Pantaneiro e Mangalarga Marchador. Maior índice de diversidade gênica foi observado na raça Pantaneiro (0,3396). No dendrograma gerado pelo método UPGMA, a partir da matriz de similaridade obtida pelo coeficiente de Jaccard, houve distinção entre as raças naturalizadas (Pantaneiro e Mangalarga Marchador) e as exóticas (Árabe e PSI). Os resultados encontrados sugerem que o Pantaneiro apresenta maior variabilidade genética que os de outras raças e está estreitamente relacionado ao Mangalarga Marchador

Theorising the links between e-HR and strategic HRM:a model, case illustration and reflections

In this paper we develop a model of e-human resources (e-HR) focusing on the relationship between HR strategy, e-HR goals and architectures, and positive and negative e-HR outcomes. This relationship is moderated by a number of key factors, including the organization and resources of the HR function, the absorptive capacity of HR, the skills and preferred styles of HR professionals, the levels of technology acceptance among employees and line managers and the models of change used in implementing e-HR programs. We illustrate certain features of this model using data from a case study of a leading international oilfield services provider. These data provide a partial confirmation of the model's validity but show the need for a more dynamic understanding of the links between e-HR variables and the importance of context in explaining differences between line managers' acceptance of e-HR