Separation of proteins by polymeric adsorbents containing azobenzene moiety as a ligand

Polymeric adsorbents containing an azobenzene moiety as a ligand were prepared, and the photoinduced adsorption behavior of proteins to the adsorbent was studied. This method regulates by light the adsorption/desorption of proteins in hydrophobic chromatography. In the dark, the amount of protein adsorbed onto the adsorbent increased with increasing hydrophobicity of either adsorbent or protein. On irradiation with UV light, the amount of protein adsorbed decreased. Such a photoinduced change of the adsorption of protein was considered to be caused by the change of the hydrophobic interaction between the adsorbent and the protein due to the photoisomerization of the azobenzene moiety accompanying the polarity change of the adsorbent. It is also found that the desorption of protein was dependent on the balance of the hydrophobicity between the adsorbents and proteins. When column chromatography was carried out, the proteins were adsorbed in the dark and could be eluted after photoirradiation, with water as the single solvent. Furthermore, mixture of proteins could be separated by using a hydrophobic gradient column which was constituted by two polymeric adsorbents having different hydrophobicity.     

Immunological activities of Capnocytophaga cellular components

Whole cells of a clinical isolate (strain S-3) of the genus Capnocytophaga were divided into cell envelope (CE) and cytoplasm (CP) fractions by mechanical disintegration followed by differential centrifugation, and a part of the CE fraction was further fractionated by sodium dodecyl sulfate (SDS) treatment into the peptidoglycan and SDS-supernatant fractions. The other part of the CE was extracted with butanol-water or hot phenol-water to isolate butanol-lipopolysaccharide and phenol-lipopolysaccharide, respectively. All of the test fractions except CP exhibited multifold immunomodulating activities, namely, the adjuvant activities to cellular as well as humoral immune responses against ovalbumin in guinea pigs, the mitogenicity on splenocytes of guinea pigs and BALB/c mice (but not on their thymocytes), the stimulation of guinea pig peritoneal macrophages (in terms of increased glucosamine uptake), and the activation of the human complement system through alternative as well as classical pathways. In addition, the test fractions other than the CP evoked dermatoxic reactions on rabbit skin with characteristic variations among them. The immunomodulating activities of SDS-supernatant were noteworthy in view of the fact that this fraction was essentially free of muramic acid and diaminopimelic acid and did not cause the gelation of horseshoe crab amoebocyte lysate except when it was used at the very high dose, suggesting that there was practically no contamination by peptidoglycans and lipopolysaccharides in the SDS-supernatant.     

Studies on a new aminoglycoside antibiotic, dactimicin. II. Isolation, structure and chemical degradation

A new aminoglycoside antibiotic, dactimicin produced by a Dactylosporangium matsuzakiense SF-2052 has been isolated by column chromatography on a cation-exchange resin and CM-sephadex. The structure of dactimicin was determined to be 4-amino-1,4-dideoxy-3-O-(2,6-diamino-2,3,4,6,7-pentadeoxy-beta-L-lyxo- heptopyranosyl)-1-[(N-formimidoylglycyl)-methylamino]-6-O-methyl-L-chiro-inosit ol. Alkaline hydrolysis of dactimicin afforded 1-N-(N-formylglycyl)fortimicin B, fortimicin B, fortimicin A and an acyl migration product, 2'-N-(N-formylglycyl)fortimicin B.     

Nd:YAG laser pumped infrared dye laser

Efficient operation of a high peak power and high-average power infrared dye laser, continuously tunable over the range of 10810-12160 Å, has been achieved by pumping with an Nd:YAG laser. A peak power as high as 4 MW with an average power of 390 MW was obtained.     

The aluminium ion as a corrosion inhibitor for iron in water

The aluminium ion was found to be an effective inhibitor for iron corrosion in water in the pH range 4.1–4.5. The effect was ascribed to the formation of a thin hydrous aluminium oxide film on the iron surface which insulates the iron from the solution. This inhibitor is characterized by high inhibitive power even under stagnant conditions as well as flowing ones.     

Three-stage time-division switching network with pulse-shifting junctor as alternate route

The configuration of a 3-stage time-division switching network which has pulse-shifting junctors as the alternate route as well as direct junctors is proposed. A computer simulation to estimate the blocking probability of the system is performed, and proves the system to be nearly as efficient as the switching network without time-slot mismatch loss.     

On estimated modes of failure of nuclear power plants by potential earthquakes

This paper deals with the estimated ‘modes of failure’ of nuclear power plants during future violent earthquakes. The authors have been surveying the damage to industrial plants caused by several violent earthquakes since 1960. Some of them have already been reported in English, but here the authors try to rearrange them from the viewpoint of ‘modes of failures’ of nuclear power plant buildings, equipment, vessels and piping. The authors categorize the mechanisms of failure as follows: (i) damaged by the dynamic effect of acceleration waves, (ii) by resonance in displacement waves, (iii) by the static effect of seismic force, (iv) by external force from attached piping and others, or forced deformation, and (v) by liquefaction of soil.The authors try to determine the modes of failure of the following items in a matrix form of the mechanisms: (i) the reactor building, (ii) steel containment vessel, (iii) auxiliary building, (iv) reactor vessel, (v) core internals, (vi) primary and secondary coolant system, (vii) emergency power supply system, (viii) emergency gas treatment system and stack, (ix) fuel cooling pond and fuel rack, (x) refuel machine crane, (xi) auxiliary system and component, (xii) turbine and its pedestal, and (xiii) main power system and control instrumentation. They also examine them from another point of view, i.e. in ‘the classification of the important factor’ of items for their aseismic design.