• BMB Reports
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• v.32 no.1
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• pp.60-66
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• 1999

Matrix metalloproteinase-2 (MMP-2; 72-kDa gelatinase; 72-kDa type IV collagenase; gelatinase A) plays an important role in normal physiological processes and in many pathologic processes such as arthritis and metastasis of cancer. Tissue inhibitor of metalloproteinases-2 (TIMP-2) binds to proMMP-2 or mature MMP-2 at a 1:1 ratio and inhibits the catalytic activity of MMP-2. We demonstrated that the baculovirus/insect cell system does not have TIMP-2 activity. The human proMMP-2 free of TIMP-2 was expressed in the expression system and purified by one-step affinity chromatography using gelatin-Sepharose. The free proMMP-2 was autoactivated to the mature MMP-2 and autodegraded into smaller molecular weight forms in the absence of external activator. The activation and autodegradation of the proMMP-2 was much more rapid in the presence of 4-aminophenylmercuric acetate (APMA). Addition of TIMP-2 inhibits both APMA-induced activation and autodegradation of the free proMMP-2. However, an increasing concentration of TIMP-2 more readily inhibited activation of the free proMMP-2 than autodegradation. These results demonstrate that TIMP-2 plays roles in inhibition of both activation and autodegradation of the free proMMP-2 in addition to inhibition of the catalytic activity of MMP-2.

• KSBB Journal
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• v.9 no.5
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• pp.532-540
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• 1994

Secretion efficiency is generally affected by promoter, signal sequence, characteristics of foreign protein and host. Secretion efficiencies of glucoamylase in recombinant plasmid-harboring yeast and chromosome-integrated yeast which had STA signal sequences were 74% and 65% at the 4th day of incubation, respectively. The high secretion efficiencies of the yeasts were obtained due to the fact that the expression levels were not reached at the secretory apparatus capacities of the host yeasts. In both yeasts, most of the intracellular glucoamylase were detected in cytoplasm and small portion (below 10%) of glucoamylase were located in periplasm. The characteristics of secreted heterologous glucoamylase from recombinant Saccharomyces cerevisiaes were investigated by using Western blot analysis. The secreted mature glucoamylase was heterogeneous and its molecular weight was about 200 to 300 kilodalton. The carbohydrate content of mature glucoamylase was higher than 80%, and several bands of about 55 to 65 kilodalton indicate the endoplasmic reticulum forms of intracellular glucoamylase.

• Korean Journal of Medicinal Crop Science
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• v.27 no.2
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• pp.108-114
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• 2019

Background: Rutin is decomposed by rutin-degrading enzymes (RDE) during the processing of buckwheat groats, resulting in a decrease in rutin content and a further increase in the bitterness of processed products. Thus, the present study aimed to examine RDE activity in groats and various tissues of domestic buckwheat varieties and to develop a method to reduce the loss of rutin during the groat processing. Methods and Results: RDE activity and isozymes patterns were determined in Tartary and common buckwheat. RDE activity, measured by quercetin production rate, was 273 and $70{\mu}g/g$ fresh weight/min in mature Tartary and common buckwheat groats, respectively. A total of six RDE isozymes were detected in mature groats of Tartary buckwheat on a non-denaturing gel. In Tartary buckwheat groats, RDE activity decreased by approximately 81 or 71% with roasting or steaming for 5 min respectively. As the roasting or steaming time increased to 30 min, RDE activity decreased by over 95%. These results indicated that RDE was inactivated in groats by roasting or steaming. When untreated Tartary buckwheat groats were kneaded with powder, RDE was activated and the quercetin production rate increased by 62%. However, when roasted groats were kneaded with powder, the quercetin production rate decreased by 93%, mainly due mainly to inactivation of RDE, as indicated by a decrease in band intensities of the six isozymes. Conclusions: These results suggested that the loss of rutin, due to RDE activity during processing, may be reduced by 71 to 100% by roasting or steaming groats for 5 to 30 min, due in large part to the inactivation of RDE isozymes.

• Journal of Plant Biotechnology
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• v.49 no.2
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• pp.131-138
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• 2022

An efficient genetic transformation protocol is a fundamental requirement for high regeneration capacity from cultivated durum wheat (Triticum durum) varieties. In this study, wereportedtheeffectsoftwoauxins,2,4-dichlorophenoxyaceticacid(2,4-D)and4-amino-3,5,6-trichloropicoli nicacid(picloram), at a concentration of 2 mg/Laloneandincombination on the embryogenic callus and plantlet regeneration of four durum wheat varieties (Amria, Chaoui, Marouane, and Tomouh) using mature embryos (MEs) and immature embryos (ImEs). Significanteffectsofvariety,culturemedium(theauxinused),andvariety-mediuminteraction were observed on the callus weight and plantlet regeneration of both MR and ImE explants. The medium used for callus induction significantly affected plantlet regeneration (p < 0.001). Comparedto2,4-D, picloram led to a higher plantlet regeneration rate in both ME and ImE explants (19.8% and 40.86%, respectively). Plantlet regeneration also varied significantly depending on the variety and medium used. PicloramledtohighplantletregenerationofbothME and ImE explants in all varieties except Tomouh, which showed high plantlet regeneration of ME explants in 2,4-D. A comparison of ME and ImE responses indicated that ImEs are the best explants for high plantlet regeneration in durum wheat. Ourfindingssuggestthatpicloramisthebestauxin and should be used instead of 2,4-D due to its positive effect on increasing plant regeneration of durum wheat ME and ImE explants.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.3
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• pp.207-214
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• 2005

After more than 100 years of development, rotating electric machines are a mature industrial product. Nevertheless, improvements are still possible for specific applications, and it is likely that the major evolution will be promoted by new materials and unconventional structures. Till now, plastic materials are an infrequent choice for the electric machines structural parts, but pioneering applications, such as aeronautical components, let some technological scouting: a low-weight/high-efficiency plastic axial flux motor for a solar flying platform is presented as an example of combined new-material/new-geometry development. The basic design aspects and the prototyping choices are presented and discussed together with the first experimental results.

• KSBB Journal
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• v.25 no.3
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• pp.257-264
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• 2010

Bone morphogenetic protein-7 (BMP-7) is one of important growth factors for skeletal development and bone growth. In this work, BMP-7 was efficiently expressed in recombinant Bacillus subtilis. The mature BMP-7 protein indicated molecular weight of 15.4 kDa by Western blot assay and was secreted into culture medium with 0.35 ng/mL. The extracellular and intracellular rhBMP-7 proteins were purified by using a FPLC system with an ion exchange column and a gel filtration column. The extracellular and intracellular rhBMP-7 proteins had finally a 57.1% purity and a 36.2% purity, respectively. The purified rhBMP-7 proteins showed an intact biological activity which stimulated alkaline phophatase (ALP) activity in MC3T3-E1 cells.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.3
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• pp.265-267
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• 1998

Cattle in Alaska seemed to be tolerant to low blood selenium (Se) although arctic winter energy demands might exacerbate oxidative damage to tissues lacking protection by Se. The thermogenic properities of brown adipose tissue (BAT) and the long cold adaptation period for Alaskan cattle indicates that they might develop BAT. Eighteen mature beef cows with whole blood Se of< 19 ppb were used to examine possible relation-ships among Se deficiency, tissue lesions, and observable BAT. All cows were wintered on a diet low in Se and nine cows were given supplemental Se provided by intraruminal bolus. Blood Se was elevated (p < .05) from November through February by supplemental Se, but body weight and back fat thickness were unaffected (p < .10). Tissues were taken from two Se deficient cows, two cows supplemented with Se, and two cows given large doses of Se (300 mg by injection) four weeks before slaughter. Histopathological examination of 187 samples of fat (7 to 55 from each cow) showed no observable amount of BAT. Examination of other tissues showed no lesions attributable to Se deficiency.

• Computers and Concrete
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• v.18 no.3
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• pp.367-388
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• 2016

In this paper, a simple practical method is introduced in which a simple weight measurement of concrete and finite element numerical analysis are used to determine the moisture transfer coefficient of concrete with a satisfactory accuracy. Six concrete mixtures with different water-to-cementitious material (w/cm) ratios and two pozzolanic materials including silica fume and zeolite were examined to validate the proposed method. The comparison between the distribution of the moisture content obtained from the model and the one from the experimental data during both the wetting and drying process properly validated the performance of the method.With the proposed method, it was also shown that the concrete moisture transfer coefficient considerably depends on the pore water saturation degree. The use of pozzolanic materials and also lowering w/cm ratio increased the moisture transfer coefficient during the initial sorption, and then, it significantly decreased with an increase in the water saturation degree.

• Advances in Traditional Medicine
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• v.9 no.4
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• pp.303-306
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• 2009

The defatted methanol extract of Raphanus sativus Linn. (Cruciferae) seed (MERS) was evaluated for its antisteroidogenic potential in mature female Swiss albino mice. The methanol extract at the doses of 100 and 200 mg/kg body weight significantly elevated the levels of cholesterol and ascorbic acid contents which serve as a precursor for the synthesis of steroid hormones in ovaries. The extract also significantly inhibited glucose-6-phosphate dehydrogenase and ${\Delta}^5-3{\beta}$-hydroxy steroid dehydrogenase, the two key enzymes involved in ovarian steroidogenesis. Hence the extract (MERS) exhibited significant antisteroidogenic activity.

• Journal of fish pathology
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• v.1 no.2
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• pp.111-116
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• 1988

There occurred a large quantity of death of the cultured carp (Cyprinus carpio) in net pens in Lake Taechong and Lake Chungju(Chungcheongbuk-do) from July through Sep., 1987. The carp were two-year-old and 500g to 2,500g in body weight. As a result of biopsy of dying carp, 1 through 10 egg-shaped giant cysts with 12 through 60mm in diameter were observed in their intestine per one carp. The author suggested that the carp were died from blockade of intestinal tract and following enteritis by the giant cysts. The giant cysts were filled with numerous mature Thelohanellus genus spores confirmed to Thelohanellus kitauei after following examination. In this case the author could find out this disease was spread by transverse infection following infestation in net pens of fingerling fish farms.