Anatomical Differences Determine Distribution of Adenovirus after Convection-Enhanced Delivery to the Rat Brain

Background: Convection-enhanced delivery (CED) of adenoviruses offers the potential of widespread virus distribution in the brain. In CED, the volume of distribution (Vd) should be related to the volume of infusion (Vi) and not to dose, but when using adenoviruses contrasting results have been reported. As the characteristics of the infused tissue can affect convective delivery, this study was performed to determine the effects of the gray and white matter on CED of adenoviruses and similar sized super paramagnetic iron oxide nanoparticles (SPIO). Methodology/Principal Findings: We convected AdGFP, an adenovirus vector expressing Green Fluorescent Protein, a virus sized SPIO or trypan blue in the gray and white matter of the striatum and external capsule of Wistar rats and towards orthotopic infiltrative brain tumors. The resulting Vds were compared to Vi and transgene expression to SPIO distribution. Results show that in the striatum Vd is not determined by the Vi but by the infused virus dose, suggesting diffusion, active transport or receptor saturation rather than convection. Distribution of virus and SPIO in the white matter is partly volume dependent, which is probably caused by preferential fluid pathways from the external capsule to the surrounding gray matter, as demonstrated by co-infusing trypan blue. Distant tumors were reached using the white matter tracts but tumor penetration was limited. Conclusions/Significance: CED of adenoviruses in the rat brain and towards infiltrative tumors is feasible when regional anatomical differences are taken into account while SPIO infusion could be considered to validate proper catheter positioning and predict adenoviral distribution

Extracellular space diffusion and extrasynaptic transmission

Summary The diffusion of neuroactive substances in the extracellular spac

The Contribution to the Study of Dentition State of the Brno Population in the 2nd Half of 18th Century and in the 19th Century

The aim of the present study is the description of dentition of skeleton remains from former Town cemetery Malá Nová (nowadays Antonínská Street), which was used as burial site in 1785-1883. A total of 1024 teeth were appraised and 3227 dental alveoli were examined. The caries intensity (I-CE) of the permanent dentition was proved to be about 38.3% and the caries frequency (F-CE) reached up to 83.8%. These two values were higher in the women. From the different types of teeth, most of dental caries were found on molars, afterwards degressively on premolars, incisors and canines. The inflammation changes of dental alveoli were found in 12.7% cases, the degenerative productive process manifestations in 8.3%, the value of the enamel hypoplasia was 4.2%, the teeth retention was observed in 33.8% individuals and the hyperodontia in 0.7% of all studied cases. Results of this study showed that the caries rate in the Brno population of 2nd half of 18th century and in the 19th century, was expressively worse than in historically older populations as well as worse than in the current population

Poly[N-(2-hydroxypropyl)methacrylamide] polymers diffuse in brain extracellular space with same tortuosity as small molecules.

Integrative optical imaging was used to show that long-chain synthetic poly[N-(2-hydroxypropyl)methacrylamide] (PHPMA) polymers in a range of molecular weights from 7.8 to 1057 kDa were able to diffuse through the extracellular space in rat neocortical slices. Tortuosity (square root of ratio of diffusion coefficient in aqueous medium to that in brain) measured with such polymers averaged 1.57, a value similar to that obtained previously with tetramethylammonium, a small cation. When PHPMA was conjugated with bovine serum albumin (BSA) to make a bulky polymer with molecular weight 176 kDa, the tortuosity rose to 2.27, a value similar to that obtained previously with BSA alone and with 70-kDa dextran. The method of image analysis was justified with diffusion models involving spherical and nonspherical initial distributions of the molecules

Magnetic and Structural Characterization of Nickel and Iron Based Heusler Ribbons Ni₂FeZ (Z = In, Sn, Sb)

Comparison of structural, chemical, and magnetic properties of Ni₂FeZ (Z = In, Sn, Sb) Heusler ribbons produced by melt-spinning method is presented. The aim of work was to prepare the Heusler alloys with the appropriate chemical composition in a single step without additional thermal treatment. Scanning electron microscopy analysis revealed polycrystalline structure of all samples. It is shown that correct L2₁ structure of Ni₂FeSb can be obtained in a single production step. On the other hand, no Heusler L2₁ phase (nor its variants) occur in Ni₂FeSn alloy. Additionally, magnetic characterization revealed high Curie temperatures of the Heusler phases (above 600 K for Ni₂FeSb and 800 K for Ni₂FeIn)

Ni 2 FeSi Heusler Glass Coated Microwires

We report on fabrication, structural and magnetic properties of novel Heusler-type glass coated Ni2FeSi microwires that were prepared by the Taylor-Ulitovsky method, having a metallic nucleus diameter about 3.9 µm and total sample diameter of 39 µm. This single step and low cost fabrication technique offers to prepare up to km of glass-coated microwires starting from few g of cheap elements for diverse applications. The X-ray diffraction data from the metallic nucleus indicates L21 crystalline structure (a = 5.563 Å), with a possible DO3 disorder. Magnetic measurements determined the Curie temperature well above the room temperature (770 K) together with uniform easy magnetization axis of the metallic core, which predisposes this material to a suitable candidate for spintronic applications