Effect of eldecalcitol on articular cartilage through the regulation of transcription factor Erg in a murine model of knee osteoarthritis

Clinical studies have reported an association between low blood levels of 25-hydroxyvitamin D and the progression of osteoarthritis (OA), but the mechanism and effects of vitamin D signaling on articular chondrocytes and cartilage remains unclear. The purpose of this study was to investigate the effects of vitamin D on articular cartilage degeneration using eldecalcitol (ED-71), which is an active vitamin D₃ analog. Eight-week old male C57BL/6NCrSlc mice were subjected to experimental surgery to induce OA and local treatments with 10 μL ED-71 (0.5 μg/mL) were administered weekly. Four and 12 weeks after surgery, joints were evaluated using histological scoring systems. In addition, gene expression was analyzed in chondrocytes that were isolated from wildtype neonatal mice, cultured, and treated with ED-71 (10^?8 M). Joints treated with ED-71 demonstrated slowed progression of OA at 4 weeks after surgery, but few effects were observed at 12 weeks after surgery. Ets-related gene (Erg) expression was upregulated in OA articular cartilage, and further increased by ED-71 treatment. In primary chondrocytes cultured with ED-71, the gene expression of Erg and lubricin/proteoglycan 4 significantly increased, as compared to that of cells cultured without ED-71. Local treatment with ED-71 reduced degenerative changes to the articular cartilage during the early phase of experimental OA. Regulation of Erg by ED-71 in articular cartilage could confer resistance to early osteoarthritic changes.     

2-Methylthio-1,4-naphthoquinone, a unique sulfur-containing quinone from a thermophilic hydrogen-oxidizing bacterium, Hydrogenobacter thermophilus

A quinone was extracted and purified from the cells of an extremely thermophilic hydrogen bacterium, Hydrogenobacter thermophilus TK-6 (IAM 12695). Its chemical structure was determined as 2-methylthio-3-VI, VII-tetrahydromultiprenyl-1,4-naphthoquinone by elemental analysis, 1H nuclear magnetic resonance spectroscopy, mass spectroscopy, and infrared spectroscopy of the quinone and by gas-liquid chromatography and gas chromatography-mass spectroscopy analysis of the ozonolysis products of the quinone. It was shown that the other five strains of H. thermophilus have the same quinone system. We named the quinone with the 2-methylthio-1,4-naphthoquinone nucleus "methionaquinone." The abbreviation of MTK is recommended for this class of quinone.     

Production of Yeast Cells from Methanol

Using immunochemical technique thermal denaturation of soybean 11S globulin, dissolved in different ionic strength solutions (µ=0~4.0) and heated at 100°C for 5 min, has been quantitatively studied. The curves of the percentage of antigenicity remaining were obtained as a function of salt concentration. The 11S globulin became strongly resistant to thermal denaturation with increasing both KCl and potassium phosphate. The stabilizing effect (in terms of percent antigenicity) was separated into three regions. At ionic strength below 0.7, potassium phosphate had no stabilizing effect while KCl had aslightly effect. The rise in stabilizing effect up to about 50%, near 1.0~1.5 µ, represented a second transition to a different denatured state which retains undissociated molecule. At rises up to 75~95%, near 2.5~3.5µ, a different conformational state resulted in which thermally denatured 11S globulin maintained almost intact native conformation after heating. The selection of an adequate ionic strength of protein solution has enabled preparation of thermally denatured 11S globulins which have desired-residual amounts of structured regions.     

Isolation and Culture Conditions of Thermophilic Hydrogen Bacteria

Isolation of thermophilic hydrogen bacteria was performed at 50°C using enrichment culture method. One of the four strains isolated, strain TH-1 grew most rapidly. Culture conditions of strain TH-1 were investigated. Optimum temperature and pH for growth proved to be 52°C and 7.0, respectively. There existed a positive correlation between the specific growth rate and the partial pressure of carbon dioxide in the gas phase. Ammonium and nitrate are the good nitrogen sources in that order. Effect of concentrations of nitrogen source, magnesium, ferrous and phosphate ions on the cell growth was also investigated. The maximum specific growth rate (μ_max) of strain TH-1 was determined as 0.68 hr^?1 by the cultivation at 52°C in a jar fermentor containing the optimal medium at pH 7.0.     

Comparison of the wild-type alpha-amylase and its variant enzymes in Bacillus amyloliquefaciens in activity and thermal stability, and insights into engineering the thermal stability of bacillus alpha-amylase

The starch hydrolysis activity and thermal stability of Bacillus amyloliquefaciens alpha-amylase (wild-type enzyme or WT) and its variant enzymes, designated as M77, M111, and 21B, were compared. All have an optimal pH at around 6, as well as almost the same reaction rates and Km and kcat values. The optimal temperature in the absence of Ca2+ ions is 60 degrees C for WT and M77 and 40 degrees C for M111 and 21B. Those of M111 and 21B rose to 50-60 degrees C upon the addition of 5 mM CaCl2, while those of WT and M77 did not change. The dissociation constants Kd for Ca2+ to WT and M77 are much lower than those of M111 and 21B. Asp233 in WT is replaced by Asn in M111 and 21B, while it is retained in M77, suggesting that Asp233 is involved in the thermal stability of the enzyme through Ca2+ ion binding. These findings provide insight into engineering the thermal stability of B. amyloliquefaciens alpha-amylase, which would be useful for its applications in the baking industry and in glucose manufacturing.     

Induction of diapause egg production in Eurytemora affinis by their own metabolites

Chemically mediated crowding effect on induction of diapause egg production in the calanoid copepod Eurytemora affinis was investigated. Two types of eggs, i.e. subitaneous and diapause eggs, produced by females that were reared in crowded culture conditions or the water from crowded culture under excess food supply were examined. 2.3% of the females that were reared at a population density of 5 or 6 animals per 10 ml of filtered lake water (FLW) produced diapause eggs. Females that were reared individually in 2-ml containers with FLW did not produce diapause eggs while 72.7% of females that were individually reared in 2-ml containers, but with water from a crowded culture (500 ind. l^–1, culture medium was changed once a week), produced diapause eggs. These results demonstrate that accumulation of their own metabolic products in the medium induces diapause egg production by E. affinis.     

Metabolism of T-2 toxin in Curtobacterium sp. strain 114-2.

The metabolic pathway of T-2 toxin in Curtobacterium sp. strain 114, one of the T-2 toxin-assimilating soil bacteria, was investigated by thin-layer and gas-liquid chromatographic analyses. T-2 toxin added to the basal medium as a single carbon and energy source was biotransformed into HT-2 toxin and an unknown metabolite. Infrared, mass spectrum, proton magnetic resonance, and other physico-chemical analyses identified this new metabolite as T-2 triol. T-2 toxin was first deacetylated by the bacterium into HT-2 toxin, and this metabolite was then biotransformed into T-2 triol without formation of neosolaniol and T-2 tetraol. No trichothecenes remained in the culture medium after prolonged culture. Some properties of T-2 toxin-hydrolyzing enzymes were observed with whole cells, the cell-free soluble fraction, and the culture filtrate. Besides T-2 toxin, trichothecenes such as diacetoxyscirpenol, neosolaniol, nivalenol, and fusarenon-X were also assimilated by this bacterium.     

Activation of Terminal Components of Human Complement by a Trypsin-Activated Complex of Human Factor B and Cobra Venom Factor

Cleavage of C3 by CVF-B? was demonstrated by hemolytic, immunoelectrophoretic and immune adherence reactions. No cleavage of C5 was detected by immunoelectrophoresis, but C5 hemolytic activity, assayed with decreased although less than C3 hemolytic activity. The co-existence of C3 with limiting amounts of C5 did not reduce the final degree of hemolysis of guinea pig erythrocytes (GPE) induced by late-acting components C6 through C9 and CVF-B?. Thus, a CVF-B? hemolytic system composed of GPE, C5 through C9 and CVF-B? provided a method for titration of terminal components of human complement. CVF-B? was able to generate hemolytically active sites of on GPE by activation of C5, C6 and C7. The complex in the fluid-phase decayed within 1 min but on GPE was quite stable. Originally insensitive sheep erythrocytes became sensitive to the CVF-B? hemolytic system if C3b sites were present, suggesting that cell-bound C3b played a role in orienting the positions of to be fixed. CVF-B? could be recovered quantitatively from the supernatant of the reaction mixture in which the hemolytically active intermediate GPEC- had been formed through the interaction between C5 to C8 and CVF-B?.