• Journal of the Institute of Electronics Engineers of Korea CI
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• v.49 no.3
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• pp.34-45
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• 2012

In this paper, we proposed and modeled a video contents protection system based on the infectious information hiding(IIH) technique as using characteristics of biological viruses. Our proposed IIH System considered the requisite important information for video contents protection as the infectious virus, and suggested a new paradigm about video contents protection that transmitted infectious information from contents(host) or video CODECs(viral vector). Also, we modeled the Pathogen, Mutant and Contagion virus as the infectious information and defined technical tools about verification of infectious information, kernel based IIH, contents based IIH and creation/regeneration of infectious information as main techniques for our IIH system. Finally, through simulations that carried the infectious information by using conventional information hiding algorithms as kernel based and contents based IIH techniques, we verified possibilities of our proposed IIH system.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1919-1924
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• 2015

Polymorphisms in the region of the interleukin IL-28 gene on chromosome 19 have been related with clearance of hepatitis C virus (HCV), a major human pathogen responsible for chronic hepatitis, cirrhosis and hepatocellular carcinoma. About 3% of the world's population is infected with HCV. The long-term response to therapy is influenced by many host and viral factors, and recent evidence has indicated that some host genetic polymorphisms related to IL-28 are the most powerful predictors of virological response in patients with HCV. This study assessed frequency of the IL-28 polymorphism (rs8099917) in 50 patients (39 men and 11 women) with chronic hepatitis C using ZNA probe real time PCR new method. All patients were tested for genotype of HCV and the HCV viral load. In parallel, the levels of SGOT, SGPT and ALK enzymes were assessed. Treatment using Peg-interferon alpha with ribavirin was conducted for patients and subsequently samples were collected to detect any change in viral load or liver enzyme rates. The overall frequency of the TT allele is 74%, TG allele 20% and GG allele 6% and the percent of patients who had T allele was 84%. Clear reduction in viral load and liver enzymes was reported in patients with the T allele. Especially for genotype 1 which is relatively resistant to treatment, these alleles may have a role in this decline. In conclusion, we showed that IL-28 polymorphism rs8099917 strongly predicts virological response in HCV infection and that real-time PCR with Zip nucleic acid probes is a sensitive, specific and rapid detection method for detection of SNPs which will be essential for monitoring patients undergoing antiviral therapy.

• Korean Journal of Veterinary Service
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• v.41 no.3
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• pp.203-210
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• 2018

Pasteurella multocida is an opportunistic organism that plays a significant role in porcine respiratory disease complex (PRDC). In the current study, we provide nationwide information of P. multocida isolates from pneumonic lungs of slaughter pigs by determining their prevalence, subspecies, biovars, capsular types, virulence-associated genes, and minimum inhibitory concentrations. P. multocida was the second most frequently confirmed (19.2%) bacterial pathogen and most of the isolates (88.9%) showed simultaneous infection with other respiratory pathogens, especially Mycoplasma hyopneumoniae (63.3%, P<0.001) and porcine circovirus type 2 (53.3%, P=0.0205). Of 42 isolates investigated, 41 (97.6%) were identified as P. multocida subspecies multocida, and only one isolate was identified as subspecies septica (biovar 5). All the isolates were capsular type A and the most prevalent biovar was biovar 3 (40.5%), followed by biovar 2 (31.0%). Comparing virulence-associated genes and biovars, all biovar 2 isolates exhibited $hgbB^-pfhA^+$ (P<0.001); all biovar 3 (P=0.0002) and biovar 13 (P=0.0063) isolates presented $hgbB^+pfhA^-$. Additionally, all biovar 2 (P=0.0037) isolates and most of biovar 3 (P=0.0265) isolates harbored tadD. P. multocida showed the highest resistance levels to oxytetracycline (73.8%), followed by florfenicol (11.9%). Continuous monitoring is required for surveillance of the antimicrobial resistance and new emerging strains of P. multocida in slaughter lines.

• The Korea Journal of Herbology
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• v.30 no.5
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• pp.15-21
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• 2015

Objectives : Methicillin-resistantStaphylococcus aureus(MRSA) is a human pathogen. New antibacterial agents are needed to treat MRSA-related infections. This study investigated the antibacterial activity of EtOH 70% extracts ofTonghyeonipal-dan(THD) which prescription is composed of oriental medicine against MRSA.Methods : The antibacterial activity of THD was evaluated against MRSA strains by using the Disc diffusion method, broth microdilution method, Checkerboard dilution test, and Time-kill test; its mechanism of action was investigated by bacteriolysis, detergent or ATPase inhibitors were used.Results : The minimum inhibitory concentration (MIC) of THD is 1,000~2,000 μg/mL against MRSA. In the checkerboard dilution test, fractional inhibitory concentration index (FICI) of THD in combination with antibiotics indicated synergy or partial synergism againstS. aureus. Furthermore, a time-kill assay showed that the growth of the tasted bacteria was considerably inhibited after 24 h of treatment with the combination of THD with selected antibiotics. For measurement of cell membrane permeability, THD 500 μg/mL along with concentration of Triton X-100 (TX) and Tris-(hydroxymethyl) aminomethane (TRIS) were used. In the other hand, N,N-dicyclohexylcarbodimide (DCCD) and Sodium azide (NaN3) were used as an inhibitor of ATPase. TX, TRIS, DCCD and NaN3 cooperation againstS. aureusshowed synergistic action.Conclusions : Accordingly, antimicrobial activity of THD was affected by cell membrane and inhibitor of ATPase were assessed. These results suggest that THD has antibacterial activity, and that THD extract offers great potential as a natural antibiotic against MRSA.

• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.130-137
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• 1983

A wide variety of pathogens are known io be seedborne, carried either as infectious mycelium internally or as contaminants on the seed coat. When seed is infected with a pathogen, the seed nay be rendered nonviable or it may remain viable but produce weak seedling. In some cases, the Infected seedling nay not be severely weakened, but nay serve as a source of primary inoculum within a community of plants. A recent problem nay be the dissemination of seedborne pathogens occurring as a result of the massive movements of seed, as a part of the 'Green revolution' Disease of great danger to agriculture may be introduced with seed from other parts of world. Seed treatment with organic mercury compounds in liquid form had become popular since about 1955. Organic mercury compounds contributed considerably to the increase in production of many crops and vegetables. In 1975, however, the use of organic mercury compound was forbidden because of doubts regarding their residual mammalian toxicity in agricultural products. Benomyl-thiram mixture, thiophanate methyl-;hiram mixture and TCMB have now been registered as seed disinfectants for the use of rice blast, brown spot and Bakanae disease. Oxathiinsthiram mixture has been registered as seed disinfectant for barley and wheat loose smut and leaf stripe of barley. Agricultural techniques have made such rapid progress that the nursery methods changed from the use of paddy nursery to box nursery designed for machine-transplanting. The spread of rice transplanting machines has caused increase of seedborne diseases. Among seedborne diseases, Bakanae disease has remarkably increased and causes much damage recently. In order to counter this trend, seed disinfectants must also be diversified. First, effective non-selective disinfectants need to be developed, and second, appropriate control methods always need to be prepared in parallel with the development of new techniques for cultivation.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.38-46
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• 2009

Lichen-forming fungi (LEF) were isolated from 67 Hungarian lichen species from ascospores or thallus fragments. LFF were successfully isolated from 26 species with isolation rate of 38.8%. Of the total number of isolation from ascospores (27 species) and thallus fragments (40 species), 48% and 32.5% of the species were successfully isolated, respectively. Comparison of rDNA sequences of ITS regions between the isolated LFF and the original thallus confirmed that all the isolates originated from the thallus fragments were LEF. The following 14 species of LEF were newly isolated in this study; Acarospora cervina, Bacidia rubella, Cladonia pyxidata, Lasallia pustulata, Lecania hyaline, Lecanora argentata, Parmelina tiliacea, Parmotrema chinense, Physconia distorta, Protoparmeliopsis muralis, Ramalina pollinaria, Sarcogyne regularis, Umbilicaria hirsuta, Xanthoparmelia conspersa and X. stenophylla. Antifungal activity of the Hungarian LFF was evaluated against plant pathogenic fungi of Colletotrichum acutatum, C. coccodes and C. gloeosporioides, causal agent of anthracnose on hot pepper. Among the 26 isolates, 11 LFF showed more than 50% of inhibition rates of mycelial growth of at least one target pathogen. Especially, LFF of Evernia prunastri, Lecania hyalina and Lecanora argentata were remarkably effective in inhibition of mycelial growth of all the tested pathogens with antibiotic mode of action. On the other hands, five isolates of Cladonia furcata, Hypogymnia physodes, Lasallia pustulata, Ramalina fastigiata and Ramalina pollinaria exhibited fungal lytic activity against all the three pathogens. Among the tested fungal pathogens, C. coccodes seemed to be most sensitive to the LFF. The Hungarian LFF firstly isolated in this study can be served as novel bioresources to develop new biofungicides alternative to current fungicides to control hot pepper anthracnose pathogenic fungi.

• Parasites, Hosts and Diseases
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• v.51 no.4
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• pp.401-412
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• 2013

Because of an increased number of Acanthamoeba keratitis (AK) along with associated disease burdens, medical professionals have become more aware of this pathogen in recent years. In this study, by analyzing both the nuclear 18S small subunit ribosomal RNA (18S rRNA) and mitochondrial 16S rRNA gene loci, 27 clinical Acanthamoeba strains that caused AK in Japan were classified into 3 genotypes, T3 (3 strains), T4 (23 strains), and T5 (one strain). Most haplotypes were identical to the reference haplotypes reported from all over the world, and thus no specificity of the haplotype distribution in Japan was found. The T4 sub-genotype analysis using the 16S rRNA gene locus also revealed a clear subconformation within the T4 cluster, and lead to the recognition of a new sub-genotype T4i, in addition to the previously reported sub-genotypes T4a-T4h. Furthermore, 9 out of 23 strains in the T4 genotype were identified to a specific haplotype (AF479533), which seems to be a causal haplotype of AK. While heterozygous nuclear haplotypes were observed from 2 strains, the mitochondrial haplotypes were homozygous as T4 genotype in the both strains, and suggested a possibility of nuclear hybridization (mating reproduction) between different strains in Acanthamoeba. The nuclear 18S rRNA gene and mitochondrial 16S rRNA gene loci of Acanthamoeba spp. possess different unique characteristics usable for the genotyping analyses, and those specific features could contribute to the establishment of molecular taxonomy for the species complex of Acanthamoeba.

• Korean Journal of Veterinary Research
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• v.50 no.4
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• pp.265-271
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• 2010

Post-weaning multisystemic wasting syndrome (PMWS) is a new emerging disease affecting nursery and growing pigs in worldwide. Porcine circovirus type 2 (PCV-2) is a most important pathogen associated with PMWS. This study was carried out to investigate the pathological changes in the pancreas of pigs diagnosed as PMWS. To detect the PCV-2 antigen and nucleic acid in the tissue, immunohistochemistry and polymerase chain reaction (PCR) was conducted, respectively. 24 pigs of 4-10 weeks old showed clinical signs of PMWS such as chronic wasting, respiratory distress and diarrhea were examined. Histopathologically, interstitial and periductular mononuclear cells infiltration were observed in pancreas. Multifocal to diffuse necrosis of acinar tissues or necrotizing to granulomatous pancreastitis with numerous syncytial cells infiltration were examined in severe cases. PCV-2 nucleic acid was detected from all tested pancreas using PCR. The PCV-2 antigen in 12 pancreas sections was detected by immunohistochemical staining. PCV-2 has a tropism for vascular endothelial cells and infiltrated macrophages. Although gross lesions are uncommon in the pancreas of pigs with PMWS, histopathological changes and the presence of PCV-2 in this tissue may be related to clinical signs associated with digestive disorders.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1402-1407
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• 2005

The fungicidal activities of Coptis japonica (Makino) extracts and their active principles were determined against Botrytis cineria, Erysiphe graminis, Phytophthora infestans, Puccinia recondita, Pyricularia grisea, and Rhizoctonia solani using a whole plant method in vivo, and compared with natural fungicides. The responses varied according to the plant pathogen tested. At 2,000 mg/l, the chloroform and butanol fractions obtained from methanolic extracts of C. japonica exhibited strong/moderate fungicidal activities against B. cinerea, E. graminis, P. recondita, and Py. grisea. Two active constituents from the chloroform fractions and one active constituent from the butanol fractions were characterized as isoquinoline alkaloids, berberine chloride, palmatine iodide, and coptisine chloride, respectively, using spectral analysis. Berberine chloride had an apparent $LC_{50}$ value of approximately 190, 80, and 50 mg/l against B. cinerea, E. graminis, and P. recondita, respectively; coptisine chloride had an $LC_{50}$ value of 210,20, 180, and 290 mg/l against B. cinerea, E. graminis, P. recondita, and Py. grisea, respectively; and palmatine iodide had an $LC_{50}$ value of 160 mg/l against Py. grisea. The isoquinoline alkaloids were also found to be more potent than the natural fungicides, curcumin and emodin. Therefore, these compounds isolated from C. japonica may be useful leads for the development of new types of natural fungicides for controlling B. cinerea, E. graminis, P. recondita, and Py. grisea in crops.

• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.765-773
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• 2009

Edwardsiella tarda is a pathogen with a broad host range that includes human and animals. The E. tarda hemolysin (Eth) system, which comprises EthA and EthB, is a noted virulence element that is widely distributed in pathogenic isolates of E. tarda. Previous study has shown that the expression of ethB is regulated by iron, which suggests the possibility that the ferric uptake regulator (Fur) is involved in the regulation of ethB. The work presented in this report supports the previous findings and demonstrates that ethB expression was decreased under conditions when the E. tarda Fur ($Fur_{Et}$) was overproduced, and enhanced when $Fur_{Et}$ was inactivated. We also identified a second ethB regulator, EthR, which is a transcription regulator of the GntR family. EthR represses ethB expression by direct interaction with the ethB promoter region. In addition to ethB, EthR also modulates, but positively, luxS expression and AI-2 production by binding to the luxS promoter region. The expression of ethR itself is subject to negative autoregulation; interference with this regulation by overexpressing ethR during the process of infection caused (i) drastic changes in ethB and luxS expressions, (ii) vitiation in the tissue dissemination and survival ability of the bacterium, and (iii) significant attenuation of the overall bacterial virulence. These results not only provide new insights into the regulation mechanisms of the Eth hemolysin and LuxS/AI-2 quorum sensing systems but also highlight the importance of these systems in bacterial virulence.