Mechanisms of Mycotoxin-Induced Neurotoxicity through Oxidative Stress-Associated Pathways

Among many mycotoxins, T-2 toxin, macrocyclic trichothecenes, fumonisin B(1) (FB(1)) and ochratochin A (OTA) are known to have the potential to induce neurotoxicity in rodent models. T-2 toxin induces neuronal cell apoptosis in the fetal and adult brain. Macrocyclic trichothecenes bring about neuronal cell apoptosis and inflammation in the olfactory epithelium and olfactory bulb. FB(1) induces neuronal degeneration in the cerebral cortex, concurrent with disruption of de novo ceramide synthesis. OTA causes acute depletion of striatal dopamine and its metabolites, accompanying evidence of neuronal cell apoptosis in the substantia nigra, striatum and hippocampus. This paper reviews the mechanisms of neurotoxicity induced by these mycotoxins especially from the viewpoint of oxidative stress-associated pathways.     

Meta-analysis of second cancer risk after radiotherapy among childhood cancer survivors

Cancer risks among childhood cancer survivors following radiotherapy have not yet been well characterised in terms of radiation dose. A meta-analysis of studies on the excess relative risk per gray (ERR) of second cancer was conducted previously; unfortunately, the small number of eligible studies restricted quantitative evaluations. To solve this problem, a statistical method to calculate ERR estimates from other estimates was developed, and a meta-analysis was conducted again. The PubMed database was searched and 26 relevant studies were identified. ERR estimates were available in 15 studies, and for the other 11 studies, the regression-based model was used to calculate ERR estimates from other estimates. The overall ERR estimate was 0.40, which was much lower than that of atomic bomb survivors exposed as young children. Heterogeneity of the risk among studies was suggested, and a further study is needed to explore the heterogeneity among studies.     

Phase diagrams and interface in inflating balloon

When a cylindrical balloon is inflated, inflation often takes place nonuniformly, inflated near one end first and followed by the growth of this part along the entire cylinder. This phenomenon is discussed from the phase‐transition perspective in terms of the Gent model, a free‐energy model that has the same structure as that of the gas–liquid transition in normal fluids. A phase diagram which describes the inflation behavior is constructed, showing the binodal and spinodal curves terminated at a critical point. The hysteresis effects are discussed based on the phase diagram. The interface between the coexisting inflated and weakly inflated regions along the cylindrical balloon is also examined, and the interfacial thickness and the interfacial energy are numerically calculated. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1393–1399, 2014     

Functional immobilization of recombinant alkaline phosphatases bearing a glutamyl donor substrate peptide of microbial transglutaminase

Covalent and site-specific protein immobilization catalyzed by microbial transglutaminase (MTG) was investigated using recombinant Escherichia coli alkaline phosphatase (AP) tagged with a glutamyl donor substrate peptide (MLAQGS) of MTG. A polystyrene surface physically coated with beta-casein or bovine serum albumin (BSA) was employed as an MTG-specific surface displaying reactive lysine residues. MTG-mediated protein immobilization through catalytic varepsilon-(gamma-glutamyl)lysine bond formation between the peptide tag of recombinant APs and beta-casein- or BSA-coated surface was verified by the detection of AP activity on the surface. It was found that the length and the insertion position of the peptide tag did not significantly affect the efficacy of enzymatic immobilization of the recombinant APs. On the other hand, pH and ionic strength in the reaction media had crucial effects on the immobilization yields. Interestingly, the optimum pH range of MTG-mediated protein immobilization differed markedly from that for an MTG-catalyzed reaction in aqueous solution. The results suggest that the concentration of reactive species due to electrostatic interaction between the enzyme-substrate intermediate and the protein-adsorbed surface is a key factor governing MTG catalysis at a solid surface.     

A cell-transverse display algorithm for regular and rectilinear 3D grid data

This paper proposes an efficient direct imaging algorithm for constructing iso-surfaces from regular and rectilinear 3D grid data in scientific and engineering visualization. The basic idea is to generate and draw polygons simultaneously by processing the cells spanned by grids in decreasing order of distance from the current viewpoint. Iso-surfaces are generated in five or six tetrahedrons into which the cells are subdivided, and are sent to a graphics device or drawn into a frame buffer on the fly. The execution order of each of the tetrahedrons is identical and is determined by the current viewpoint. Since the algorithm does not need to store intermediate polyhedral data and does not require a depth buffer memory for hidden surface removal, it is applicable to a large quantity of data on a 3D grid, such as computed tomography (CT) data. It is also particularly powerful for semi-transparent display, because transparency calculation can be reduced to image compositing operations if the polygons are drawn in order of their z-depth from the current viewpoint.