• Journal of Microbiology and Biotechnology
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• v.16 no.1
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• pp.5-14
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• 2006

Streptomycetes are Gram-positive microorganisms producing secondary metabolites through unique physiological differentiation [4]. The microbes show unusual morphological differentiation to form substrate mycelia, aerial mycelia, and arthrospores on solid medium [19]. Substrate mycelium growth is sustaining with sufficient nutrients in the culture medium. The concentration of a specific individual substrate in the culture environment is the most important extracellular factor allowing vegetative mycelia growth, where extracellular hydrolytic enzymes participate in the utilization of waterinsoluble substrates. However, with starvation of nutrients in the culture medium, the vegetative mycelia differentiate to aerial mycelia and spores. It has been considered that shiftdown of essential nutrients for mycelia growth is the most important factor triggering morphological and physiological differentiation in Streptomyces spp. Since proteineous macromolecule compounds are the major cellular components, these are faced to endogenously metabolize following a severe depletion of nitrogen source in culture nutrients (Fig. 1). Various proteases were identified of which production was specifically related with the phase of mycelium growth and also morphological differentiation. The involvement of proteases and protease inhibitor is reviewed as a factor explaining the mycelium differentiation in Streptomyces spp.

• International Journal of Human Ecology
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• v.16 no.1
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• pp.1-10
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• 2015

Within the field of international adoption, little research has examined the involvement of fathers in cultural socialization practices. Using secondary data analysis with a sample of 332 international adoptive fathers and mothers, the present study examined international adoptive fathers' cultural socialization practices and compared these practices with those of international adoptive mothers. The results indicated that 1) family cultural socialization practices mainly engaged in by fathers were those that require little to no integration with people of the children's race and/or ethnicity, and 2) fathers' awareness or practices were found to be similar to those of mothers. This study illustrates the importance of continuing research on fathers' beliefs, attitudes, and practices in relation to the race and birth culture of their internationally adopted children.

• Journal of Plant Biology
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• v.37 no.3
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• pp.263-269
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• 1994

Involvement of ethylene and Ca2+ on the induction of phenylalanine ammonia-lyase (PAL) was investigated in Daucus carota L. suspension culture system. Ethylene production started to increase about 3 h after glucan treatment. And the maximal induction of ethylene was preceded by PAL induction by 30 min. After the treatment of ethrel, PAL activity was increased. When cells were treated with glucan and Co2+, PAL activity was simultaneously reduced. Ethylene production was reduced dramatically in calcium-free medium, even though glucan was treated. PAL activity and ethylene producton was inhibited conspicuously when ethylene glycolbis($\beta$-aminoethyl ether) N,N,N',N'-tetraacetic acid (EGTA) was treated with glucan. Verapamil and trifluoperazine also inhibited PAL activity. When cells were treated with calcium ionophore A23187, PAL activity was increased in nontreated medium. We report here PAl activity is increased in related to ethylene production and involvement of Ca2+ in glucan-treated carrot suspension cells.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.3
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• pp.211-220
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• 2007

Objective: In organotypic culture of immortalized human oral keratinocytes (IHOK), the change of the growth and differentiation was investigated according to the fibroblast type and the involvement of mitogen-activated protein (MAP) kinase. Materials & Methods: IHOK was cultured three dimensionally with gingival fibroblast (GF), dermal fibroblast (DF) and immortalized gingival fibroblast (IGF). We characterized biologic properties of three dimensionally reconstructed IHOK by histological, immunohistochemical, and Western blot analysis. We also investigated whether MAP kinase pathway was involved in epithelial-mesenchymal interaction by Western blot analysis. Results: The best condition of three dimensionally cultured IHOK was the dermal equivalent consisting of type I collagen and IGF. IGF increased the expression of more proliferating cell nuclear antigen (PCNA), involucrin than GF and DF in response to co-culture with IHOK. Extracellularly regulated kinase (ERK) pathway was activated in organotypic co-culture with IGF. Conclusion: The organotypic co-culture of IHOK with dermal equivalent consisting of type I collagen and IGF resulted in excellent morphologic and immunohistochemical characteristics and involved ERK pathway. The epithelial-mesenchymal interaction was activated according to the fibroblast type.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2000.10a
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• pp.125-139
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• 2000

The differential enhanced degradation of cis- and trans-1,3-D was observed in the previous two studies performed by Ou et al. (1995) and especially Chung et al. (1999). This study was initiated to investigate the involvement of microorganisms in the differential enhanced degradation of the chemicals. As expected, microorganisms were responsible for the enhanced degradation of the chemicals. A mixed bacterial culture capable of degrading 1,3-D was isolated from an enhanced soil sample collected from a site treated with 1,3-D. Similar to the enhanced soil, the mixed culture degraded trans-1,3-D faster than cis-1,3-D. This mixed culture could not utilize cis- and trans-1,3-D as a sole source of carbon for growth. Rather, a variety of second substrates were evaluated to stimulate the differential enhanced degradation of the two isomers. As a result, the mixed culture degraded cis- and trans-1,3-D only in the presence of a suitable second substrate. Second substrates that had the capacity to stimulate the degradation included soil leachate, tryptone, tryptophan, and alanine. Other substrates tested, including soil extract, glucose, yeast extract, and indole (ailed to stimulate the degradation of the two isomers. Therefore, it appeared that the degradation of cis- and trans-1,3-D was a cometabolic process. The mixed culture was composed of four morphologically distinctive bacterial colonies.

• Safety and Health at Work
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• v.5 no.2
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• pp.60-65
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• 2014

Background: To elucidate the relationship between safety culture maturity and safety performance of a particular company. Methods: To identify the factors that contribute to a safety culture, a survey questionnaire was created based mainly on the studies of $Fern{\acute{a}}ndez-Mu{\tilde{n}}iz$ et al. The survey was randomly distributed to 1000 employees of two oil companies and realized a rate of valid answer of 51%. Minitab 16 software was used and diverse tests, including the descriptive statistical analysis, factor analysis, reliability analysis, mean analysis, and correlation, were used for the analysis of data. Ten factors were extracted using the analysis of factor to represent safety culture and safety performance. Results: The results of this study showed that the managers' commitment, training, incentives, communication, and employee involvement are the priority domains on which it is necessary to stress the effort of improvement, where they had all the descriptive average values lower than 3.0 at the level of Company B. Furthermore, the results also showed that the safety culture influences the safety performance of the company. Therefore, Company A with a good safety culture (the descriptive average values more than 4.0), is more successful than Company B in terms of accident rates. Conclusion: The comparison between the two petrochemical plants of the group Sonatrach confirms these results in which Company A, the managers of which are English and Norwegian, distinguishes itself by the maturity of their safety culture has significantly higher evaluations than the company B, who is constituted of Algerian staff, in terms of safety management practices and safety performance.

• BMB Reports
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• v.34 no.5
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• pp.421-427
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• 2001

Osteoclasts, cells primarily involved in bone resorption, originate from the hematopoietic precursor cells of the monocyte/macrophage lineage and differentiate into multinucleated mature forms. We developed an in vitro osteoclast culture system using embryonic chicken bone marrow cells. This culture system can be utilized in studies on the differentiation and function of osteoclasts. Phosphatidylinositol 3-kinase (PI3-kinase) and mitogen-activated protein kinases (MAPKs) have been implicated in diverse cellular functions including proliferation, migration, and survival. Using the developed avian osteoclast culture system, we examined the involvement of these kinases in osteoclast differentiation by employing specific inhibitors of the kinases. We Found that the inhibition of the PI 3-kinase, p38, or ERK interfered with osteoclast formation, suggesting that the signaling pathways that involve these molecules participate in the process of chicken osteoclast differentiation.

• The Plant Pathology Journal
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• v.24 no.3
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• pp.328-336
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• 2008

Out of various fungi and bacteria tested for inhibition of Tobacco mosaic virus(TMV) infection using Nicotiana tabacum cv. Xanthi-nc, a bacterial isolate JB-l, identified as Pseudomonas putida had a strong direct inhibitory activity against the TMV infection. Its systemic or indirect activity was also noted at more than a half level of the direct control efficacy. Disease severity was reduced significantly in the susceptible tobacco N. tabacum cv. NC 82 by the treatment of the bacterial culture filtrate, somewhat more by the pretreatment than by simultaneous treatment, probably by inhibiting the TMV transmission and translocation in the plants, showing negative serological, which responses in the viral detection by DAS-ELISA. TMV-inhibitory substances from P. putida JB-1 were water-soluble, stable to high temperature(even boiling), and to a wide range of pH. As proteinase K nullified their antiviral activity, the TMV inhibition activity of P. putida may be derived from proteinaceous materials. In electron microscopy, TMV particles treated with the JB-1 culture were shown to be shrunken with granule-like particles attached on them. All of these aspects suggest that P. putida JB-1 may be developed as a potential agent for the control of TMV.

• The Journal of the Korean Society for Microbiology
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• v.35 no.2
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• pp.117-127
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• 2000

The non-ELR-containing CXC chemokines Mig and IP-10 have been shown to function as chemotactic cytokines for activated T lymphocytes. In this study, we examined the potential involvement of Mig and IP-10 in antimycobacterial response of mice immunized or infected with M. bovis BCG. The accumulation of Mig and IP-10 mRNA in resident peritoneal monocytes ($RPM{\Phi}$) was slightly reduced by stimulation with vBCG, and the degree was greater for 24 hr culture even though IFN-${\gamma}$ was added. Expression of Mig, IP-10, and IFN-${\gamma}$ in 24 hr delayed-type hypersensitivity (DTH) response was stronger in vBCG-immune mice than in the non-immune. The increase of DTH measured by foot-pad thickness appears to be clearly related to the levels of chemokines Mig and IP10 messages and those of IFN-${\gamma}$ and IL-12. Stimulation with vBCG for 2 days decreased or completely dropped the levels of Mig message in non-immune or immune splenocytes, respectively, whereas IP-10 message was slightly decreased in 2 days culture. Moreover, messages for IL-12 (p40) showed similar kinetics for Mig. The levels of Mig and IP-10 mRNA during the course of infection with BCG were not readily changed in lungs, livers, and spleens from BCG-infected mice. Although there was no obvious changes of Mig and IP-10 messages in the target organs during infection process, we found that the infection progressed over the first 3 wk before being contained by the emerging immune response suggested from detectable amount of IFN-${\gamma}$ mRNA around this time. In view of selectivity of chemokines Mig and IP-10 for activated T cells, these data suggest that chemokine Mig and IP-10, especially in collaboration with IL-12 and IFN-${\gamma}$, may playa role as T cell recruiters in immune response against mycobacterial infection.

• Journal of Photoscience
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• v.9 no.2
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• pp.5-8
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• 2002

Photoperiodism is an important adaptive phenomenon in various physiological parameters including reproduction to cope with seasonal changes. Involvement of extraretinal photoreceptors in the photoperiodism in non-mammalian vertebrates has been well established. In addition, circadian clock system is known to be involved in the photoperiodic time measurement. The pathway consists of light-input system, time measurement system (circadian clock), gonadotropin releasing hormone (GnRH) production in the hypothalamus, luteinizing hormone (LH) and follicle stimulating hormone (FSH) production in the pituitary, and final gonadal development. Recently, several laboratories reported photopigments newly cloned in the pineal, eyes and deep brain in addition to already known visual pigments in the retina. These are pinopsin, parapinopsin, VA-opsin, melanopsin, etc. All these photopigments belong to the opsin family having retinal as the chromophore. However, the function of these photopigments remains unknown. I reviewed the studies on the location of the photopigments by immunocytochemistry. I also discussed the results on the action spectra for induction of gonadal development in relation with the location of the photoreceptors. Various physiologically active substances distribute in the vertebrate brain. Such substances are GnRH, GnIH, neuropeptide Y, vasoactive intestinal peptide, c-Fos, galanin, neurosteroids, etc. I summarized the immunhistochemical studies on the distribution and the photoperiodic changes of these substances and discussed the route from the deep brain photoreceptor to GnRH cells.