• The Plant Pathology Journal
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• 제37권6호
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• pp.505-511
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• 2021

Interaction of a pathogen with its host plant requires both flexibility and rapid shift in gene expression programs in response to environmental cues associated with host cells. Recently, a growing volume of data on the diversity and ubiquity of internal RNA modifications has led to the realization that such modifications are highly dynamic and yet evolutionarily conserved system. This hints at these RNA modifications being an additional regulatory layer for genetic information, culminating in epitranscriptome concept. In plant pathogenic fungi, however, the presence and the biological roles of RNA modifications are largely unknown. Here we delineate types of RNA modifications, and provide examples demonstrating roles of such modifications in biology of filamentous fungi including fungal pathogens. We also discuss the possibility that RNA modification systems in fungal pathogens could be a prospective target for new agrochemicals.

• 한국어병학회지
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• 제17권3호
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• pp.179-189
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• 2004

Morphological structure and sporogenesis of myxosporean parasite, Parvicapsula anisocaudata from cultured olive flounder, Paralichthys olivaceus were examined by light and transmission electron microscopies. Numerous round early stages, spindle-shaped disporic or monosporic pseudoplasmodia, asymmetrical thin-walled mature spores were found inthe lumen of renal tubule and urinary bladder. Long pseudopodia or short projections from cytoplasm of pseudoplasmodia make the parasite attach firmly to host tissues. Spore development was mono- or disporous with no pansporoblast formation. Sporoplasmic cell was partially surrounded by two capsulogenic cells, and capsulogenic cells were enveloped by two flattened valvogenic cells. Capsulogenesis and valvogenesis followed general patterns seen in that of other myxosporean.

• 대한의생명과학회지
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• 제17권3호
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• pp.185-190
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• 2011

Adenovirus type 5 (Ad5) vectors have been used for gene transfer to a wide variety of cell types in vivo and in vitro. The advantages of adenovirus vectors include the high titer of virus readily obtained in large scale preparations, their ability to transduce dividing and non dividing cells, and the high level of transgene expression. Since adenovirus vectors do not integrate in host cell DNA, there is a lack of insertional mutagenesis. However, many human tumor cells lack expression of the adenovirus 5 receptors and contain areas of hypoxia. In order to identify the pattern of replication and gene expression of oncolytic adenovirus in hypoxic condition, multiple different fiber modified Ads (Ad5F/S11, Ad5F/S35, Ad5F/K7, Ad5F/K21, and Ad5F/RGD) was compared. The replication of all fiber modified adenovirus was inhibited in hypoxic condition in HEK 293 cells, but gene expression has variety on different tumor cell lines and the level of coxackievirus and adenovirus receptor (CAR) expression. These data suggest that CAR expression pattern and hypoxic condition of tumor are considered for optimal oncolytic adenovirus application.

• 대한산업공학회지
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• 제21권1호
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• pp.137-151
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• 1995

A difficult problem in operating Flexible Manufacturing Systems (FMS) is to control the system in real-time by coordinating heterogeneous machines and integrating distributed information. The objective of the paper is to present the models and methodologies useful to resolve the difficult problem. The detailed objectives can be described in three folds. First, a hierarchical Colored and Timed Petri-Net (CTPN) is designed to control an FMS in real-time. The concerned FMS consists of a loading station, several machining cells, a material handling system, and an unloading station. Timed-transitions are used to represent the timed-events such as AGV movements between stations and cells, part machining activities in the cells. Signal places are also used to represent communication status between the host and the cell controllers. To resolve the event conflicts and scheduling problems, dispatching rules are introduced and applied. Second, an implementation methodology used to monitor and diagnose the errors occurring on the machines during system operation is proposed. Third, a Petri-Net simulator is developed to experiment with the designed control logic.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2000년도 춘계학술대회
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• pp.8-9
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• 2000

Despite the advances made in the past few decades in cancer chemotherapy, many conventional anticancer drugs display relatively poor selectivity for cancer cells. The nonselectivity of anticancer drugs and the development of anticancer drug resistance have been recognized as serious limitations in their clinical usefulness. Therefore, a major challenge in cancer chemotherapy is the development of new anticancer agents with improved selectivity for tumor cells as well as the prevention of the host cell resistance, both of which result in the improvement of therapeutic effect against cancer cells. Cyclophosphamide (CP), a widely used anticancer agent, is a prodrug that is activated by hepatic microsomal mixed-function oxidase (MFO) catalyzed C$_4$- hydroxylation. The resulting 4-hydroxycyclophosphamide (4-OH-CP) is converted to the ring-opened tautomer to aldophosphamide (Aldo) which subsequently undergoes a base- catalyzed ${\beta}$-elimination to generate cytotoxic phosphoramide mustard (PDA) and acrolein. The cytotoxic activity of CP is attributed to the aziridinium ion species derived from PDA that cross-links interstrand DNA.

• Asian-Australasian Journal of Animal Sciences
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• 제7권3호
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• pp.427-434
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• 1994

The primordial germ cells (PGCs) were transfected in vitro and expressed the exogenous RSVLTR/${\beta}G2$ plasmid, suggesting thaI PGC is a possible vector for direct gene transfer into the germ line. Transfection efficiency of cell suspensions containing PGCs was 1.5% by liposome mediated DNA transfection. By microinjection of the transfected PGCs into the host germinal crescent, PGCs migrated via blood vessel to the future gonad and these transfected PGCs resulted in the RSVLTR/${\beta}G2$ expression in the gonad. The results from the seeding of PGCs on the chorioallantoic membrane were insufficient to test the hypothesis that PGCs can penetrate or invade the chorioallantoic membrane for transport via the circulatory system.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.265-268
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• 2002

Lactate and ammonia are two major toxic waste products formed during mammalian cell culture. Accumulation of the side products have negative effects of on cell growth and specific production rate. In this study, K-562 cells were used as the host cell of a recombinant protein. Effects of carbon sources were invetigated focused on the cell culture span, the accumulation of lactate and ammonia in culture of recombinant K-562 cells.

• The Plant Pathology Journal
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• 제31권4호
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• pp.421-427
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• 2015

Citrus scab disease is one of the destructive diseases that reduce the value of fruit for the fresh market. We analyzed the process of symptom development after infection with scab pathogen $Elsino{\ddot{e}}$ fawcettii in the susceptible satsuma mandarin leaves to observe the structural modification against pathogen. The cuticle and epidermal cells along with 3-5 layers of mesophyll tissue were degraded 1-2 days post inoculation. Surrounding peripheral cells of degraded tissues grew rapidly and then enveloped the necrotic area along with the growing conidia. Cross sections through the lesion revealed hyphal colonization in epidermis and mesophyll tissues. In response to the pathogen colonization, host cell walls were lignified, inner cells were rapidly compartmentalized and a semi-circular boundary was formed that separated the infected region from the non-infected region, and finally prevented the intercellular pathogen spread.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.621-621
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• 2003

I. Objectives In order to examine the immunoresponse of host cells to Enterococcus faecalis, this in vitro study monitored the production of Interleukin-2(IL-2), Interleukin-4(IL-4) and Transforming growth $factor-{\beta}1(TGF-{\beta}1)$ in human lymphocytes. II. Materials and methods Enterococcus faecalis(ATCC29212) strains were used in this study. Strains were grown in 1-liter cultures in 85% N2-10% H2-5% $CO_2$chamber for 3 days at $37^{\circ}C$. The medium used was 3.7% brain heart infusion broth. Bacterial cells harvested from 1-liter cultures were washed, suspended in 20ml of phosphate-buffered saline(PBS). Suspensions of bacterial cells were disrupted by sonication on ice for 5 min. Protein concentration was determined by the Bicinchoninic acid(BCA) protein assay.(omitted)

• 대한의생명과학회지
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• 제25권3호
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• pp.201-210
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• 2019

The oncolytic viruses selectively infect and destroy cancer cells, not harming normal cells. The cancer cell materials released by oncolysis, like tumor antigens, stimulate host antitumor immune responses, which is a long-lasting antitumor immunity removing cancer cells in remote parts of the body by a systemic response. Oncolytic viruses armed with transgenes such as cytokines or other immune stimulating factors enhance the immune responses. The first oncolytic virus approved by US-FDA is $Imlygic^{(R)}$ targeting for melanoma. The oncolytic virus is considered as a revolutionary immunotherapy for tumors together with immune checkpoint inhibitors. A variety of oncolytic viruses are under research in the treatment of kidney cancer, liver cancer, breast cancer, and many others solid tumors. Clinical trials have shown promising results in different types of cancers. Here, we present a brief introduction of various aspects of oncolytic virus, and a review of the current status of oncolytic virus therapy development.