• Title/Summary/Keyword: host cells

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Inefficient Transmissibility of NS-Truncated H3N8 Equine Influenza Virus in Dogs

  • Na, Woonsung;Song, Manki;Yeom, Minjoo;Park, Nanuri;Kang, Bokyu;Moon, Hyoungjoon;Jeong, Dae-Gwin;Kim, Jeong-Ki;Song, Daesub
    • Journal of Microbiology and Biotechnology
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    • v.25 no.3
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    • pp.317-320
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    • 2015
  • H3N8 equine influenza virus (EIV) causes respiratory diseases in the horse population, and it has been demonstrated that EIV can transmit into dogs owing to its availability on receptors of canine respiratory epithelial cells. Recently, we isolated H3N8 EIV from an EIV-vaccinated horse that showed symptoms of respiratory disease, and which has a partially truncated nonstructural gene (NS). However, it is not clear that the NS-truncated EIV has an ability to cross the host species barrier from horses to dogs as well. Here, we experimentally infected the NS-truncated H3N8 EIV into dogs, and monitored their clinical signs and viral load in respiratory organs to determine the virus's transmissibility.

Adaptive Resource Allocation Schemes in Wireless Mobile Networks (무선 이동 네트워크에서의 적응적 자원 할당 방법)

  • Kang, Yoo-Hwa;Suh, Young-Joo;An, Syung-Og
    • Journal of KIISE:Information Networking
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    • v.28 no.4
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    • pp.477-488
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    • 2001
  • In wireless networking environments, supporting guaranteed quality of service to mobile hosts is difficult due to the facts that wireless networks have limited bandwidth and mobile hosts frequently move in and out of cells. In spite of the characteristics of wireless communications, the quality of some types of services, i.e., real-time services, must be guaranteed at a certain level. When a mobile host moves into another cell, service rates for mobile hosts in wireless networks may be adjusted since wireless networks have limited bandwidths. In this paper, we propose two resource allocation algorithms in wireless mobile networks, using quality of service (QoS) specifications. For efficient use of resources of wireless networks, the proposed algorithms dynamically allocate rates of flows in proportion to QoS with limited resources.

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A Mixed Formulation of Lactic Acid Bacteria Inhibits Trinitrobenzene-Sulfonic-Acid-Induced Inflammatory Changes of the Colon Tissue in Mice

  • Cha, Yeon Suk;Seo, Jae-Gu;Chung, Myung-Jun;Cho, Chung Won;Youn, Hyun Joo
    • Journal of Microbiology and Biotechnology
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    • v.24 no.10
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    • pp.1438-1444
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    • 2014
  • Lactic acid bacteria (LAB) are probiotics that provide numerous beneficial effects on the host body, especially on the intestine. Combining several strains of LAB, we prepared a formulation containing four different LAB and studied its anti-inflammatory activity both in vitro and in vivo. The formulation significantly reduced NO production from RAW 264.7 cells treated with bacterial lipopolysaccharide, indicating that the formulation might include anti-inflammatory activity. The formulation also suppressed inflammatory change induced by trinitrobenzene sulfonic acid (TNBS) in mice, where oral or rectal administration of the formulation protected the colon tissue from the damage by TNBS. Expressions of the IL-6 and FasL genes appeared to be down-regulated by the formulation in TNBS-treated colon tissues, suggesting that the suppression of those genes may be involved in the anti-inflammatory activity of the formulation.

Probiotic Potential of Pediococcus acidilactici and Enterococcus faecium Isolated from Indigenous Yogurt and Raw Goat Milk

  • Sarkar, Shovon Lal;Hossain, Md. Iqbal;Monika, Sharmin Akter;Sanyal, Santonu Kumar;Roy, Pravas Chandra;Hossain, Md. Anwar;Jahid, Iqbal Kabir
    • Microbiology and Biotechnology Letters
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    • v.48 no.3
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    • pp.276-286
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    • 2020
  • Probiotics are live microorganisms that, when administered in adequate amounts, confer health benefits to the host. This study was conducted for the isolation of potential lactic acid bacteria (LAB) with probiotic properties from goat milk and yogurt. Several tests were conducted in vitro using the standard procedures for evaluating the inhibitory spectra of LAB against pathogenic bacteria; tolerance to NaCl, bile salt, and phenol; hemolytic, milk coagulation, and bile salt hydrolase activities; gastrointestinal transit tolerance; adhesion properties; and antibiotic susceptibility. Among 40 LAB strains screened according to culture characteristics, five isolates exhibited antagonistic properties. Three were identified as Pediococcus acidilactici, and two were identified as Enterococcus faecium, exploiting 16S rRNA gene sequencing. All the isolates succeeded in the gastrointestinal transit tolerance assay and successively colonized mucosal epithelial cells. Based on the results of these in vitro assays, both P. acidilactici and E. faecium can be considered as potential probiotic candidates.

Biophysical therapy and biostimulation in unfavorable bony circumstances: adjunctive therapies for osseointegration

  • Kim, Yong-Deok
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.38 no.4
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    • pp.195-203
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    • 2012
  • Dental implants using titanium have greatly advanced through the improvement of designs and surface treatments. Nonetheless, the anatomical limits and physiological changes of the patient are still regarded as obstacles in increasing the success rate of implants further, even with the enhancement of implant products. So there have been many efforts to overcome these limits. The intrinsic potential for bone regeneration can be stimulated through adjuvant treatments with the continuous improvement of implant properties, and this can play an important role in achieving optimum osseointegration toward peripheral bone tissue and securing ultimate long-term implant stability in standard surgical procedures. For this purpose, various chemical, biological, or biophysical measures were developed such as bone grafts, materials, pharmacological agents, growth factors, and bone formation proteins. The biophysical stimulation of bone union includes non-invasive and safe methods. In the beginning, it was developed as a method to enhance the healing of fractures, but later evolved into Pulsed Electromagnetic Field, Low-Intensity Pulsed Ultrasound, and Low-Level Laser Therapy. Their beneficial effects were confirmed in many studies. This study sought to examine bone-implant union and its latest trend as well as the biophysical stimulation method to enhance the union. In particular, this study suggested the enhancement of the function of cells and tissues under a disadvantageous bone metabolism environment through such adjunctive stimulation. This study is expected to serve as a treatment guideline for implant-bone union under unfavorable circumstances caused by systemic diseases hampering bone metabolism or the host environment.

Carbon Fibres for the Repair of Abdominal Wall Defects in Rabbits

  • Gangwar, A.K.;Sharma, A.K.;Kumar, Naveen;Maiti, S.K.;Kumar, N.;Gupta, O.P.;Goswami, T.K.;Singh, Rajendra
    • Carbon letters
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    • v.6 no.1
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    • pp.15-24
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    • 2005
  • Sixteen clinically healthy New Zealand white rabbits of either sex were divided into two equal groups I and II of 8 animals each. Under thiopental sodium (2.5%) anaesthesia a linear full thickness abdominal wall defect of 3 cm in length was created and repaired with continuous suture pattern using 3000 filaments of carbon fibres and 1~0 black braided nylon suture, ingroup I and II respectively. Increased vascularity was observed in carbon fibres (group I) and on day 30 the carbon fibres were covered by white fibrous tissue. Significantly higher (P < 0.05) values of glucose was seen on day 14 in group I, whereas, decrease in glucose value was observed in group II. Histopathologically, the carbon fiber implant induced extensive fibrous tissue (collagen fiber) reaction. Negligible inflammatory cells in the stroma indicate the host tissue tolerance to carbon fibers. Histochemically, gradually increased alkaline phosphatase activity up to day 14 in group I, suggested the proliferation of fibroblasts in early stages.

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Exposure to Environmental Endotoxin and Health Effects (환경 중의 엔도톡신 노출 및 건강에 미치는 영향)

  • Park, Ju-Hyeong
    • Journal of Environmental Health Sciences
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    • v.40 no.4
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    • pp.265-278
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    • 2014
  • Microbes such as bacteria, fungi, archaea, protists, and viruses are ubiquitous and people are exposed to them continuously. Endotoxin is a component of the outer membrane of Gram-negative bacteria and a potent proinflammaotry substance. When a person is exposed to environmental endotoxin, an innate immune response is initiated upon the initial recognition and this response produces various inflammatory mediators and recruits inflammatory cells to the exposed tissues. A purified chemical form of endotoxin is called lipopolysaccharide (LPS), and the lipid A portion of the molecule is a biologically active moiety. Exposure to endotoxin may result in various complex health effects depending on time, route, and dose of exposure, as well as host susceptibility. Gene-environment interactions play important roles in health effects of endotoxin exposure, e.g. development or aggravation of asthma. To accurately assess exposure to endotoxin in environmental or epidemiologic studies, methods of sampling, extraction, and analysis must be carefully selected since the selected methods may substantially affect analytical results and there is no internationally-agreed standard method to date. The lack of a standardized method hampers the establishment of exposure-response relationships. While an internationally-agreed health-based exposure limit does not exist, the Dutch Expert Committee on Occupational Safety recently recommended $90EU/m^3$ as a health-based occupational exposure limit. The current article reviews various scientific issues on how we measure environmental endotoxin and the health effects of endotoxin exposure.

Antimicrobial Peptides (AMPs): Peptide Structure and Mode of Action

  • Park, Yoon-Kyung;Hahm, Kyung-Soo
    • BMB Reports
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    • v.38 no.5
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    • pp.507-516
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    • 2005
  • Antimicrobial peptides (AMPs) have been isolated and characterized from tissues and organisms representing virtually every kingdom and phylum. Their amino acid composition, amphipathicity, cationic charge, and size allow them to attach to and insert into membrane bilayers to form pores by 'barrel-stave', 'carpet' or 'toroidal-pore' mechanisms. Although these models are helpful for defining mechanisms of AMP activity, their relevance to resolving how peptides damage and kill microorganisms still needs to be clarified. Moreover, many AMPs employ sophisticated and dynamic mechanisms of action to carry out their likely roles in antimicrobial host defense. Recently, it has been speculated that transmembrane pore formation is not the only mechanism of microbial killing by AMPs. In fact, several observations suggest that translocated AMPs can alter cytoplasmic membrane septum formation, reduce cell-wall, nucleic acid, and protein synthesis, and inhibit enzymatic activity. In this review, we present the structures of several AMPs as well as models of how AMPs induce pore formation. AMPs have received special attention as a possible alternative way to combat antibiotic-resistant bacterial strains. It may be possible to design synthetic AMPs with enhanced activity for microbial cells, especially those with antibiotic resistance, as well as synergistic effects with conventional antibiotic agents that lack cytotoxic or hemolytic activity.

Naturally occurring reoviruses for human cancer therapy

  • Kim, Manbok
    • BMB Reports
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    • v.48 no.8
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    • pp.454-460
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    • 2015
  • Naturally occurring reoviruses are live replication-proficient viruses that specifically infect human cancer cells while sparing their normal counterpart. Since the discovery of reoviruses in 1950s, they have shown various degrees of safety and efficacy in pre-clinical or clinical applications for human anti-cancer therapeutics. I have recently discovered that cellular tumor suppressor genes are also important in determining reoviral tropism. Carcinogenesis is a multi-step process involving the accumulation of both oncogene and tumor suppressor gene abnormalities. Reoviruses can exploit abnormal cellular tumor suppressor signaling for their oncolytic specificity and efficacy. Many tumor suppressor genes such as p53, ataxia telangiectasia mutated (ATM), and retinoblastoma associated (RB) are known to play important roles in genomic fidelity/maintenance. Thus, a tumor suppressor gene abnormality could affect host genomic integrity and likely disrupt intact antiviral networks due to the accumulation of genetic defects which in turn could result in oncolytic reovirus susceptibility. This review outlines the discovery of oncolytic reovirus strains, recent progresses in elucidating the molecular connection between oncogene/tumor suppressor gene abnormalities and reoviral oncotropism, and their clinical implications. Future directions in the utility of reovirus virotherapy is also proposed in this review. [BMB Reports 2015; 48(8): 454-460]

Post-Translational Regulation of miRNA Pathway Components, AGO1 and HYL1, in Plants

  • Cho, Seok Keun;Ryu, Moon Young;Shah, Pratik;Poulsen, Christian Peter;Yang, Seong Wook
    • Molecules and Cells
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    • v.39 no.8
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    • pp.581-586
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    • 2016
  • Post-translational modifications (PTMs) of proteins are essential to increase the functional diversity of the proteome. By adding chemical groups to proteins, or degrading entire proteins by phosphorylation, glycosylation, ubiquitination, neddylation, acetylation, lipidation, and proteolysis, the complexity of the proteome increases, and this then influences most biological processes. Although small RNAs are crucial regulatory elements for gene expression in most eukaryotes, PTMs of small RNA microprocessor and RNA silencing components have not been extensively investigated in plants. To date, several studies have shown that the proteolytic regulation of AGOs is important for host-pathogen interactions. DRB4 is regulated by the ubiquitin-proteasome system, and the degradation of HYL1 is modulated by a de-etiolation repressor, COP1, and an unknown cytoplasmic protease. Here, we discuss current findings on the PTMs of microprocessor and RNA silencing components in plants.