• 한국환경과학회지
• /
• 제4권5호
• /
• pp.447-459
• /
• 1995

Volatile organic compounds(VOCs) are of concern for their potential chronic toxicity, their suspected role in the formation of smog, and their suspected role in destruction of stratospheric ozone. Present study evaluated the exposures to selected VOCs in three microenvironments: 2 chlorinated and 5 aromatic VOCs in the indoor and outdoor air, and 5 aromatic VOCs in the breathing zone air of gas-service station attendants. With permissible Quality Assurance and Quality Control performances VOC concentrations were measured 1) to be higher in indoor air than in outdoor air, 2) to be higher in two Taegu residential areas than in a residential area of Hayang, and 3) to be higher in the nighttime than in the daytime. Among five aromatics, Benzene and Toluene were two most highly measured VOCs in breathing zone air of service station attendants. Based on the sum of VOC concentrations, the VOC exposure during refueling was estimated to be about 10% of indoor and outdoor exposures. For Benzene only, the exposure during refueling was estimated to cause about 52% of indoor and outdoor exposure. The time used to calculate the exposures was 2 minutes for refueling and 24 hours for indoor and outdoor exposures.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권10호
• /
• pp.4867-4871
• /
• 2012

Cervical cancer is a leading cause of morbidity and mortality in women worldwide. Although the human papillomavirus (HPV) is considered the major causative agent of cervical cancer, yet the viral infection alone is not sufficient for cancer progression. The etiopathogenesis of cervical cancer is indeed complex; a precise understanding of the complex cellular/molecular mechanisms underlying the initiation, progression and/or prevention of the uterine cervix is therefore essential. Autophagy is emerging as an important biological mechanism in targeting human cancers, including cervical cancer. Furthermore, autophagy, a process of cytoplasm and cellular organelle degradation in lysosomes, has been implicated in homeostasis. Autophagic flux may vary depending on the cell/tissue type, thereby altering cell fate under stress conditions leading to cell survival and/or cell death. Autophagy may in turn govern tumor metastasis and subsequent carcinogenesis. Inflammation is a known hallmark of cancer. Vascular insufficiency in tumors, including cervical tissue, leads to depletion of glucose and/or oxygen perturbing the osmotic mileu causing extracellular acidosis in the tumor microenvironment that may eventually result in autophagy. Thus, targeted manipulation of complex autophagic signaling may prove to be an innovative strategy in identification of clinically relevant biomarkers in cervical cancer in the near future.

• Journal of Microbiology and Biotechnology
• /
• 제11권5호
• /
• pp.727-738
• /
• 2001

Macrophagal polykaryocytes (MPs) are terminally differentiated multinuclear macrophage cells responsible for remodeling and resorption of bone, foreign body, and tissue deposition in inflammation. MPs are encountered only in bone and cartilagenous tissues, in which they are referred to as osteoclasts, odontoclasts, in which they are referred to as osteoclasts, odontoclasts, and septoclasts. Depending on the disease, the MPs differentiate into many morphological variants that include foreign-body giant cells, Langhans-type cells, and Touton-type cells. Morphological heterogeneity of MPs could Touton-type cells. Morphological heterogeneity of MPs could reflect the giant cell formation from phenotypically different marophage precursors by the process of fusion. At present, many cytokines, adhesion/fusion molecules, and other factors of the microenvironment have been discovered that influence the multinucleation process. Many evidences suggest that conditions in giant cell fibrohistiocytomas, which facilitate MP formation, are similar to the inflammation site of granulomatosis. MPs in the giant cell tumors and granulomatosis foci are formed in response to the factors secreted by mesenchymal cells. It is proposed that one of the first steps in vertebrate evolution could be the organization of skeleton remodeling, in which osteoclasts play a major role. In this step, the same mechanism of regulations served as a basis for the development of both osteoclast and inflammatory forms of MPs.

• 산학경영연구
• /
• 제3권
• /
• pp.47-75
• /
• 1990

This study focuses on the ecological and environmental approach for marketing in the attempt to harmonize the objectives and resources of the organizations with the changing environment. This study presents the deductive and nomative method for analyzing recurrent marketing problem and contains seven chapters. The marketing environment is the place the company must start in searching for oportunities and in monitoring threats. It consists of all the actors and forces that affect the company's ability to transact can be divided into two componets-The marketing environment comperies a microenvironment consists of the actors in the company's immediate environment that affect its ability to serve its customers, namely, the company, market channal firms, customers, competitors and publics, the macroenvironment consists of the larger societal forces that affect all the actors in the macroenvironment, nanly, the demographic, economic, natural, technological and cultural forces. Most marketing executives took the phyisical environment for granted. Few consistered it one of the most dynamic elements in the totoal environment of business. However, two development have brought the physical environment to the forefront of business decision. The first has been labeled the ecological crisis-the polution and deterioration of air, water and land, the second is the accelerated depletion of the earth's natural resources. Currently, most product are designed to obtain an optimum combination of customer acceptances and production and distribution efficiencies. If we look to the future, products increasingly will be planned to obtain an optimum combination of market acceptance increasingly, efficiency and environmental protection. The entire ecological cycle of product will have to be considered.

• KSBB Journal
• /
• 제11권5호
• /
• pp.511-517
• /
• 1996

본 연구에서는 친수성기질과 소수성기질을 함께 수용하는 수용성 상용용매를 사용하여 반응매질의 친수성과 소수성이 알킬글루코시드의 합성반응에 적 합하도록 조절된 양친매질을 개발하고 hydrophili C city control이 이루어진 효소반응기술을 이용하여 효소의 활성도와 안정성, 기질의 가용화, 얄킬글루코 시드의 수율과 농도의 관점에셔 가장 바람직한 양친 매상 효소반응공정 (amphiphilic phase enzyme re action process)을 제시하였으며, 핵실글루코시드, 옥틸글루코시드, 데실글루코시드 및 도데실글루코시 드를 합성한 결과 생생물 농도는 각각 18.2, 9.68, 7.27, 6.03g/L을 얻였다.

• The Korean Journal of Physiology and Pharmacology
• /
• 제14권5호
• /
• pp.331-336
• /
• 2010

In rapidly growing tumors, hypoxia commonly develops due to the imbalance between $O_2$ consumption and supply. Hypoxia Inducible Factor (HIF)-$1{\alpha}$ is a transcription factor responsible for tumor growth and angiogenesis in the hypoxic microenvironment; thus, its inhibition is regarded as a promising strategy for cancer therapy. Given that CamKII or PARP inhibitors are emerging anticancer agents, we investigated if they have the potential to be developed as new HIF-$1{\alpha}$-targeting drugs. When treating various cancer cells with the inhibitors, we found that a CamKII inhibitor, KN-62, effectively suppressed HIF-$1{\alpha}$ specifically in hepatoma cells. To examine the effect of KN-62 on HIF-$1{\alpha}$-driven gene expression, we analyzed the EPO-enhancer reporter activity and mRNA levels of HIF-$1{\alpha}$ downstream genes, such as EPO, LOX and CA9. Both the reporter activity and the mRNA expression were repressed by KN-62. We also found that KN-62 suppressed HIF-$1{\alpha}$ by impairing synthesis of HIF-$1{\alpha}$ protein. Based on these results, we propose that KN-62 is a candidate as a HIF-$1{\alpha}$-targeting anticancer agent.

• Molecules and Cells
• /
• 제37권9호
• /
• pp.637-643
• /
• 2014

Wound healing is a complex multi-step process that requires spatial and temporal orchestration of cellular and non-cellular components. Hypoxia is one of the prominent microenvironmental factors in tissue injury and wound healing. Hypoxic responses, mainly mediated by a master transcription factor of oxygen homeostasis, hypoxia-inducible factor-1 (HIF-1), have been shown to be critically involved in virtually all processes of wound healing and remodeling. Yet, mechanisms underlying hypoxic regulation of wound healing are still poorly understood. Better understanding of how the wound healing process is regulated by the hypoxic microenvironment and HIF-1 signaling pathway will provide insight into the development of a novel therapeutic strategy for impaired wound healing conditions such as diabetic wound and fibrosis. In this review, we will discuss recent studies illuminating the roles of HIF-1 in physiologic and pathologic wound repair and further, the therapeutic potentials of HIF-1 stabilization or inhibition.

• Journal of Pharmaceutical Investigation
• /
• 제36권4호
• /
• pp.231-237
• /
• 2006

Hypoxia in solid tumors is known to contribute to intrinsic chemoresistance. Histocultures are in vitro 3 dimensional cultures of tumor tissues and maintain the characteristic microenvironment of human solid tumors in vivo including hypoxia and multicellular structure. In this study, we evaluated the pharmacodynamics of tirapazamine(TPZ), a hypoxia-selective cytotoxin, in human non small cell lung cancer(NSCLC) cells grown as monolayers and histocultures. Antiproliferative activity of TPZ was determined after various conditions of drug exposure, and cell cycle arrest and apoptosis were also measured using flow cytometry. In monolayers, hypoxia selectivity measured by hypoxic/normoxic cytotoxicity ratio was increased with longer exposure. Lower cytotoxicity of TPZ was observed in histocultures compared to monolayers, however, a similar level of cytotoxicity was obtained with longer exposure of 96 hr. TPZ induced $G_2/M$ arrest and apoptosis in both culture conditions, which were greatly enhanced under hypoxic condition. Our data clearly showed the different pharmacodynamics of TPZ in monolayers and histocultures. Antiproliferative activity of TPZ against human solid tumors can be improved with longer drug exposure by exploiting drug delivery systems or by combining angiogenesis inhibitors to maintain drug concentration in tumor tissues.

• Bulletin of the Korean Chemical Society
• /
• 제25권12호
• /
• pp.1917-1923
• /
• 2004

Although the proteolytic activity of the Cu(II) complex of cyclen (Cyc) is greatly enhanced upon attachment to a cross-linked polystyrene (PS), the Cu(II)Cyc-containing PS derivatives reported previously hydrolyzed only a very limited number of proteins. The PS-based artificial metalloproteases can overcome thermal, mechanical, and chemical instabilities of natural proteases, but the narrow substrate selectivity of the artificial metalloproteases limits their industrial application. In the present study, artificial metalloproteases exhibiting broad substrate selectivity were synthesized by attaching Cu(II)Cyc to a PS derivative using linkers with various structures in an attempt to facilitate the interaction of various protein substrates with the PS surface. The new artificial metalloproteases hydrolyzed all of the four protein substrates (albumin, myoglobin, ${\gamma}$-globulin, and lysozyme) examined, manifesting $k_{cat}/K_m$ values of 28-1500 $h_{-1}M_{-1}$ at 50 $^{\circ}C$. The improvement in substrate selectivity is attributed to steric and/or polar interaction between the bound protein and the PS surface as well as the hydrophobicity of the microenvironment of the catalytic centers.

• BMB Reports
• /
• 제49권1호
• /
• pp.11-17
• /
• 2016

The gastrointestinal tract forms the largest surface in our body with constantly being exposed to various antigens, which provides unique microenvironment for the immune system in the intestine. Accordingly, the gut epithelium harbors the most T lymphocytes in the body as intraepithelial lymphocytes (IELs), which are phenotypically and functionally heterogeneous populations, distinct from the conventional mature T cells in the periphery. IELs arise either from pre-committed thymic precursors (natural IELs) or from conventional CD4 or CD8αβ T cells in response to peripheral antigens (induced IELs), both of which commonly express CD8α homodimers (CD8αα). Although lineage commitment to either conventional CD4 T helper (Th) or cytotoxic CD8αβ T cells as well as their respective co-receptor expression are mutually exclusive and irreversible process, CD4 T cells can be redirected to the CD8 IELs with high cytolytic activity upon migration to the gut epithelium. Recent reports show that master transcription factors for CD4 and CD8 T cells, ThPOK (Th-inducing BTB/POZ-Kruppel-like factor) and Runx3 (Runt related transcription factor 3), respectively, are the key regulators for re-programming of CD4 T cells to CD8 lineage in the intestinal epithelium. This review will focus on the unique differentiation process of IELs, particularly lineage re-commitment of CD4 IELs. [BMB Reports 2016; 49(1): 11-17]