Anti-Kir4.1 Antibodies in Multiple Sclerosis: Specificity and Pathogenicity

The glial cells in the central nervous system express diverse inward rectifying potassium channels (Kir). They express multiple Kir channel subtypes that are likely to have distinct functional roles related to their differences in conductance, and sensitivity to intracellular and extracellular factors. Dysfunction in a major astrocyte potassium channel, Kir4.1, appears as an early pathological event underlying neuronal phenotypes in several neurological diseases. The autoimmune effects on the potassium channel have not yet been fully described in the literature. However, several research groups have reported that the potassium channels are an immune target in patients with various neurological disorders. In 2012, Srivastava et al. reported about Kir4.1, a new immune target for autoantibodies in patients with multiple sclerosis (MS). Follow-up studies have been conducted by several research groups, but no clear conclusion has been reached. Most follow-up studies, including ours, have reported that the prevalence of Kir4.1-seropositive patients with MS was lower than that in the initial study. Therefore, we extensively review studies on the method of antibody testing, seroprevalence of MS, and other neurological diseases in patients with MS. Finally, based on the role of Kir4.1 in MS, we consider whether it could be an immune target in this disease.     

Identification and analysis of specific chromosomal region adjacent to exogenous Dhfr-amplified region in Chinese hamster ovary cell genome

Chinese hamster ovary (CHO) cells are widely used for the stable production of recombinant proteins. Gene amplification techniques are frequently used to improve of protein production, and the dihydrofolate reductase (DHFR) gene amplification system is most widely used in the CHO cell line. We previously constructed a CHO genomic bacterial artificial chromosome (BAC) library from a mouse Dhfr-amplified CHO DR1000L-4N cell line and one BAC clone (Cg0031N14) containing the CHO genomic DNA sequence adjacent to Dhfr was selected. To identify the specific chromosomal region adjacent to the exogenous Dhfr-amplified region in the CHO cell genome, we performed further screening of BAC clones to obtain other Dhfr-amplified regions in the CHO genome. From the screening by high-density replica filter hybridization using a digoxigenin-labeled pSV2-dhfr/hGM-CSF probe, we obtained 8 new BAC clones containing a Dhfr-amplified region. To define the structures of the 8 BAC clones, Southern blot analysis, BAC end sequencing and fluorescence in situ hybridization (FISH) were performed. These results revealed that all the selected BAC clones contained a large palindrome structure with a small inverted repeat in the junction region. This suggests that the obtained amplicon structure in the Dhfr-amplified region in the CHO genome plays an important role in exogenous gene amplification.     

Comparison of Brain Temperature Distribution in Mathematical and Solid Models of Head Thermal Characteristics

Accurate temperature control of brain tissue during hypothermia treatment is necessary in order to prevent secondary brain damage and to avoid various side effects. Thus, the visualization of the intracerebral temperature distribution in hypothermia treatment was studied at the fundamental level. For this purpose a virtual reality technology was used to create a mathematical model that reflects metabolic heat production and Fourier heat conduction in a brain with the necessary parameters based on various clinical models. In the present study, an experimental system was developed to examine a mathematical simulation of the blood flow in a human head by using a solid brain model constructed using silicon rubber in the shape of a brain based on MRI data, taking into account the metabolic heat given off by three film heaters and including six sensors for the measurement of regional brain temperature. The mathematical simulation describes the internal temperature distribution in a brain with a similar structure to the brain solid model. The results of mathematical simulations and experiments using the brain solid model were quite consistent in the steady state, including control of regional temperature. This allows for the performance of heat conduction experiments under conditions similar to those of a living body, in which the internal temperature is clinically difficult to observe. Thus, the mathematical simulation is confirmed to be useful together with experiments using the solid model for the study of future brain hypothermia treatment.     

A POSSIBLE USE OF PHOTO-REACTION IN LIQUID-LIQUID EXTRACTION OF SUBSTITUTION-INERT METAL COMPLEXES. EXTRACTION OF CHROMIUM(III) AND COBALT(III) COMPLEXES.

A liquid-liquid extraction of chromium(III) ion was achieved by a cooperative action of light (photoreduction) and conventional extractants on chromium(VI) species. The extraction of chromium spcies was studied by both molecular and atomic absorption spectrophotometry measurements. Trioctylphosphine oxide (TOPO) was the most effective among the extractants studied (TOPO, dibutylsulfoxide, tributyl phosphate, 2-ethyhexyl hydrogen 2-ethylhexylphosphonate, di (2,4,4-trimethylpentyl)-phosphinic acid). A back-extraction of chromium(III) species to aqueous solution was also promoted by photo-irradiation. The nature of the extraction system was studied under various operational conditions such as wavelength of illuminating light, coordinating ah ionic species in aqueous solution, and coexisting metal ions. A liquid- liquid (back-) extraction of some     

Uptake of heavy metal ions from aqueous solution using Mg–Al layered double hydroxides intercalated with citrate, malate, and tartrate

Mg–Al layered double hydroxide (Mg–Al LDH) was modified with organic acid anions using a coprecipitation technique, and the uptake of heavy metal ions from aqueous solution by the Mg–Al LDH was studied. Citrate·Mg–Al LDH, malate·Mg–Al LDH, or tartrate·Mg–Al LDH, which had citrate³⁻ (C₆H₅O₇³⁻), malate²⁻ (C₄H₄O₅²⁻), or tartrate²⁻ (C₄H₄O₆²⁻) anions intercalated in the interlayer, was prepared by dropwise addition of a mixed aqueous solution of Mg(NO₃)₂ and Al(NO₃)₃ to a citrate, malate, or tartrate solution at a constant pH of 10.5. These Mg–Al LDHs were found to take up Cu²⁺ and Cd²⁺ rapidly from an aqueous solution at a constant pH of 5.0. This capacity was mainly attributable to the formation of the citrate–metal, malate–metal, and tartrate–metal complexes in the interlayers of the Mg–Al LDHs. The uptake of Cu²⁺ increased in the order malate·Mg–Al LDH < tartrate·Mg–Al LDH < citrate·Mg–Al LDH. The uptake of Cd²⁺ increased in the order malate·Mg–Al LDH < tartrate·Mg–Al LDH = citrate·Mg–Al LDH. These differences in Cu²⁺ and Cd²⁺ uptake were attributable to differences in the stabilities of the citrate–metal, malate–metal, and tartrate–metal complexes. These results indicate that citrate³⁻, malate²⁻, and tartrate²⁻ were adequately active as chelating agents in the interlayers of Mg–Al LDHs.     

Operando X-ray Absorption Spectroscopy Study of Pt/γ-Al<Subscript>2</Subscript>O<Subscript>3</Subscript> During the Total Oxidation of C<Subscript>3</Subscript>H<Subscript>6</Subscript>

Operando X-ray absorption fine structure (XAFS) investigations were performed on Pt/γ-Al₂O₃ during the total oxidation of C₃H₆ in reducing and oxidizing atmospheres. Study of the Pt valance state and catalytic conversion behavior as a function of temperature revealed that both the creation of metallic Pt sites and the activation of adsorbed species on Pt are important for the functioning of the catalytic reaction at low temperature.     

Fabrication and applications of cellulose nanoparticle‐based polymer composites

The impressive mechanical properties, reinforcing capability, abundance, low weight, low filler load requirements, and biodegradable nature of nanoparticles from bioresources such as cellulose, make it an ideal candidate for the development of green polymer nanocomposites. Significant amount of research in this area is primarily focused on the extraction, qualitative surface modification, and evaluation of mechanical performance after filling in polymer matrixes at different ratios. The extreme agglomeration tendency, hydrophilic nature, difficult dispersion in many organic solvents of cellulose nanoparticles are the challenging obstacles when fabrication of such nanocomposites is concerned. Traditional processing of polymer composites mainly through extrusion and melt compounding, is not easily possible in case of cellulose nanocomposites due to higher possibility of poor dispersion and degradation of nanofibers. Therefore, issues related to the fabrication of nanofiber‐based products and their application appears to be one of the most important areas in order to enhance their competitiveness with other nanoparticles. This review is aimed to summarize the recent accomplishments and issues involving the use of cellulose nanoparticles in the development of new polymeric materials. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers     

MEASUREMENT OF CONCENTRATIONS OF POLYCYCLIC AROMATIC HYDROCARBONS AND DIOXIN COMPOUNDS IN CANINE LUNGS

Polycyclic aromatic hydrocarbons (PAHs) and dioxin compounds remaining in canine lungs were measured with an alkaline decomposition method employing KOH/ethanol. PAHs extracted from the lungs of 31 dogs were between 0.07 and 0.47 ng/wet-g (mean: 0.19 ng/wet-g) for BaA; 0.03 and 0.16 ng/wet-g (mean: 0.08 ng/wet-g) for BkF; 0.05 and 0.29 ng/wet-g (mean: 0.13 ng/wet-g) for BaP; and 0.05 and 0.35 ng/wet-g (mean: 0.17 ng/wet-g) for BghiP. Dioxin concentrations were between 0.047 and 0.870 pg-TEQ/wet-g (mean: 0.179 pg-TEQ/wet-g). There were big differences between the PAH concentrations and dioxin concentrations in the canine lungs. Strong relationships were observed between individual PAHs (r = 0.73–0.95). In this study, we detected PAHs and dioxins in all samples, confirming that canine lungs were contaminated by those pollutants.