Associations between glia, neurons and prion protein (PrPsc) deposits in variant Creutzfeldt-Jakob disease (vCJD)

Glia may be important in the pathology of variant Creutzfeldt-Jakob disease (vCJD) in several ways: (1) glial cells could be involved in the formation of prion protein (PrPsc) deposits, (2) PrPsc deposits could stimulate the production of astrocytes and microglia, (3) PrPsc deposits could damage adjacent glial cells, and (4) glial cells could remove PrPsc from the brain. To investigate the significance of glial cells in vCJD, the relationships between PrPsc deposits and their associated glia, together with neurons and blood vessels, was studied in six cases of vCJD. Multicentric PrPsc deposits were the largest and least frequent type of deposit observed and were more commonly associated with glial cells, neuronal perikarya, and blood vessels than the more common diffuse and florid PrPsc deposits. Diffuse PrPsc deposits were more frequently associated with glial cells and neurons than the florid deposits. The ratio of astrocytes to oligodendrocytes adjacent to PrPsc deposits was similar to normal brain but the ratio of astrocytes and oligodendrocytes to microglia was less than in normal brain. The intensity of immunolabelling of multicentric PrPsc deposits was positively correlated with the presence of associated vacuoles and negatively correlated with the frequency of microglia. The patterns of correlation between deposit morphology and associated glial cells and neurons were similar for the diffuse and florid type PrPsc deposits. Deposit size was most consistently correlated with the number of associated neurons and vacuoles. The data suggest in vCJD: (1) no evidence that glia were necessary for the formation of PrPsc deposits, (2) an increase in microglia which may be an attempt to remove PrPsc from the bain, and (3) PrPsc deposits could affect adjacent astrocytes and damage the blood brain barrier (BBB).

Glia and the pathology of variant Creutzfeldt-Jakob disease (vCJD)

Glia may be implicated in the pathology of variant Creutzfeldt-Jakob disease (vCJD) in several ways: (1) glial cells could be involved in the formation of prion protein (PrPsc) deposits, (2) PrPsc deposits could stimulate the production of astrocytes and microglia, (3) PrPsc deposits could damage adjacent glial cells, and (4) glial cells could remove aggregates of PrPsc from the brain. To clarify the significance of glial cells in vCJD, the relationship between PrPsc deposits and their associated glia, together with neurons and blood vessels, was studied in six cases of vCJD. Multicentric PrPsc deposits were the largest and least frequent type of deposit observed and were more commonly associated with glial cells, neuronal perikarya, and blood vessels than the more common diffuse and florid PrPsc deposits. Diffuse PrPsc deposits were more frequently associated with glial cells and neurons than the florid deposits. The ratio of astrocytes to oligodendrocytes adjacent to PrPsc deposits was similar to normal brain but the ratio of astrocytes or oligodendrocytes to microglia was less than in normal brain. The intensity of immunolabelling of multicentric PrPsc deposits was positively correlated with the presence of associated vacuoles and negatively correlated with the frequency of microglia. The patterns of correlation between deposit morphology and associated glial cells and neurons were similar for the diffuse and florid type PrPsc deposits. Deposit size was most consistently correlated with the number of associated neurons and vacuoles. The data suggest in vCJD: (1) there was no evidence that glia were necessary for the formation of PrPsc deposits, (2) there is an increase in microglia which may be an attempt to remove PrPsc from the bain, and (3) PrPsc deposits could affect adjacent astrocytes and damage the blood brain barrier (BBB). © 2013 by Nova Science Publishers, Inc. All rights reserved.

The influence of composition on the optical properties of electrodeposited gold

In industry the colour of a gold alloy electrodeposit is checked by visual comparison with standard panels. The aims of the present work have been to access the application of spectrophotmetric techniques to the measurement of the colour of gold alloy electrodeposits and to examine the factors that influence the colour of thin deposits. The minimum thickness of deposit required to produce its final colour and completely hide the underlying substrate was measured and found to depend on the nature of the substrate, the plating solution and the operating conditions. Bright and matt electrodeposits were studied. The influence of alloying gold by adding copper, silver and indium to the plating solution were investigated. CIE chromaticity coordinates were calculated from spectrophotometric data using a computer programme written for the purpose. The addition of silver to a simple gold bath caused the colour of the deposit to change from yellow through green to near white in a smooth progression as the amount of silver in solid solution steadily increased. The colour of deposits formed when additions of copper were made was complicated by the formation of intermediate phases. À colour in the blue region of the spectrum was obtained in a few experiments investigating the influence of indium additions to the gold bath.

Metformin - The gold standard:a scientific handbook

Metformin may play in important role in the future in helping to prevent the development of diabetes: it is a strong candidate therapy for delaying the onset of the disease and potentially as part of a treatment programme to correct features of the metabolic syndrome. This book celebrates 50 years of research into metformin and its use in the treatment of diabetes. Metformin is still the drug of choice for managing patients with type 2 diabetes and all new drugs are tested in comparison with this, the gold standard. Comprising seven sections, addressing different aspects of research on metformin and its applications, this book is edited by a world class team of expert diabetologists and beautifully presented in two colour throughout. It also includes a bibliography of all papers published on metformin and a complete list of all authors on those papers.

Selective oxidation of cyclohexene through gold functionalized silica monolith microreactors

Two simple, reproducible methods of preparing evenly distributed Au nanoparticle containing mesoporous silica monoliths are investigated. These Au nanoparticle containing monoliths are subsequently investigated as flow reactors for the selective oxidation of cyclohexene. In the first strategy, the silica monolith was directly impregnated with Au nanoparticles during the formation of the monolith. The second approach was to pre-functionalize the monolith with thiol groups tethered within the silica mesostructure. These can act as evenly distributed anchors for the Au nanoparticles to be incorporated by flowing a Au nanoparticle solution through the thiol functionalized monolith. Both methods led to successfully achieving even distribution of Au nanoparticles along the length of the monolith as demonstrated by ICP-OES. However, the impregnation method led to strong agglomeration of the Au nanoparticles during subsequent heating steps while the thiol anchoring procedure maintained the nanoparticles in the range of 6.8 ± 1.4 nm. Both Au nanoparticle containing monoliths as well as samples with no Au incorporated were tested for the selective oxidation of cyclohexene under constant flow at 30 °C. The Au free materials were found to be catalytically inactive with Au being the minimum necessary requirement for the reaction to proceed. The impregnated Au-containing monolith was found to be less active than the thiol functionalized Au-containing material, attributable to the low metal surface area of the Au nanoparticles. The reaction on the thiol functionalized Au-containing monolith was found to depend strongly on the type of oxidant used: tert-butyl hydroperoxide (TBHP) was more active than H2O2, likely due to the thiol induced hydrophobicity in the monolith.