• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.76-92
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• 1997

Porpilyromonas endodontalis is specifically involved in endodontic infections. The bacterium can be isolated almost exclusively only from infected rool canals. P. gingivalis also has been implicated in endodontic infection. Pathogemcity of P. gingival is is attributed to a variety of virulence factors, especially proteases, produced by the bacterium. Importance of P. endodontalis in endodontic infection has been revealed. However, the pathogenic property of P. endodontalis has not been extensively studied. The present study was undertaken to characterize the proteolytic activity of P. endodontalis and compare the activity with that of P. gingivalis which has the most potent and diverse proteases among oral bacteria. For this purpose, culture supematants(SUP) and cell extracts(CE) were obtained from these two bacteria and were subjected to zymography using 15% polyacrylamide gel copolymerized with gelatin, type I, IV collagens or albumin. Hydrolysis of the collagens was further investigated by the cleavage assay using native type I and IV collagens in solution-phase. The results were as follows: 1. P. endodontalis apparently has a proteolytic activity that is comparable with that of P. gingivalis. 2. SUP and CE obtained from P. endodontalis and P. gingival is showed the strongest activity for gelatin, followed by type I and IV collagens, and albumin. 3. In the zymography, no noticeable difference in proteolytic activity for gelatin and albumin between the SUP and CE was observed, but in the cleavage assay using native collagens, the SUP showed a stronger collagenolytic activity than the CE. 4. The gelatinolytic activity of both the SUP and CE from these two bacteria was diminished in the presence of $CaCl_2$ or reducing agents such as ${\beta}$-mercaptoethanol and dithiothreitol(DTT). 5. Type I(calf skin and human placenta) collagenolytic activity of P. endodontalis and P. gingivalis was reduced by DTT but not affected by $CaCl_2$. The inhibitory effect of DTT, however, was reduced to some extent by $CaCl_2$. 6. Type IV collagenolytic activity of these two bacteria was not affected by $CaCl_2$ but increased to some extent in association with the reducing agents. 7. Hydrolysis of albumin by P. endodontalis and P. gingivalis was demonstrated only in the presence of the reducing agents. The overall results indicate that with respect to proteolytic activity, P. endodontalis appears to be as potent as P. gingivalis, or maybe more, and its proteolytic characteristic is similar to that of P. gingivalis. This suggests that P. endodontalis has so potent proteolytic activity that can participate by itself in endodontic infections and apical periodontitis, causing tissue destruction.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1366-1372
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• 2018

Objective: A disintegrin and metallopeptidase with thrombospondin motifs type 8 (ADAMTS8) is crucial for diverse physiological processes, such as inflammation, tissue morphogenesis, and tumorigenesis. The chicken ADAMTS8 (chADAMTS8) gene was differentially expressed in the kidney following exposure to different calcium concentrations, suggesting a pathological role of this protein in metabolic diseases. We aimed to examine the molecular characteristics of chADAMTS8 and analyze the gene-expression differences in response to toll-like receptor 3 (TLR3) stimulation. Methods: The ADAMTS8 mRNA and amino acid sequences of various species (chicken, duck, cow, mouse, rat, human, chimpanzee, pig, and horse) were retrieved from the Ensembl database and subjected to bioinformatics analyses. Reverse-transcription polymerase chain reaction (RT-PCR) and quantitative PCR (qPCR) experiments were performed with various chicken tissues and the chicken fibroblast DF-1 cell line, which was stimulated with polyinosinic-polycytidylic acid (poly[I:C]; a TLR3 ligand). Results: The chADAMTS8 gene was predicted to contain three thrombospondin type 1 (TSP1) domains, whose amino acid sequences shared homology among the different species, whereas sequences outside the TSP1 domains (especially the amino-terminal region) were very dif­ferent. Phylogenetic analysis revealed that chADAMTS8 is evolutionarily clustered in the same clade with that of the duck. chADAMTS8 mRNA was broadly expressed in chicken tissues, and the expression was significantly up-regulated in the DF-1 cells in response to poly(I:C) stimulation (p<0.05). These results showed that chADAMTS8 may be a target gene for TLR3 signaling. Conclusion: In this report, the genetic information of chADAMTS8 gene, its expression in chicken tissues, and chicken DF-1 cells under the stimulation of TLR3 were shown. The result suggests that chADAMTS8 expression may be induced by viral infection and correlated with TLR3-mediated signaling pathway. Further study of the function of chADAMTS8 during TLR3-dependent inflammation (which represents RNA viral infection) is needed and it will also be important to examine the molecular mechanisms during different regulation, depending on innate immune receptor activation.

• Journal of Life Science
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• v.25 no.2
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• pp.214-222
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• 2015

Aeromonas hydrophila is the most common water fish pathogen and cause diseases such as hemorrhagic septicemia, dropsy, ulceration and asymptomatic septicemia. A. hydrophila secretes many extracellular products (ECPs) which contribute to effective infection, wide distribution and great adaptability to environmental changes. Crude ECPs of A. hydrophila CK257, a strain used in this study, exhibits a toxic activity to the animals including mouse, rabbit and fish. Toxic symptoms were indicated by tissue damage and skin injuries in animal. When ECPs were subcutaneously injected to animals, skin damages were observed, appearing like necrosis. Preliminary research demonstrated that the active factors are protein component. The crude ECPs were collected after ammonium sulfate precipitation of cell-free culture supernatant. ECPs were fractionated with the use gel filtration chromatography. Five ECP fractions were obtained, of which one fraction was found to be toxic to goldfish. MALDI-TOF analyses provided two interesting proteases called M35 and M28. Both M35 and M28 are known as metalloprotease. Accordingly, proteins in an active fraction exhibited caseinolytic activity. These proteins were difference of caseinolytic activity under different metallic ions. Also active fraction has elastolytic activity. These results suggested that peptidase M28 and M35 may be a candidate factor for tissue necrosis activity about infection with A. hydrophila.

• Tuberculosis and Respiratory Diseases
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• v.42 no.4
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• pp.618-623
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• 1995

Cryptococcosis is a systemic mycosis that most often involves the lungs and central nervous system and, less frequently, the skin, skeletal system, and prostate gland. Cryptococcus neoformans, the causative organism, is a yeastlike round or oval fungus, 4 to $6{\mu}m$ in diameter, which is surrounded by a polysaccharide capsule and reproduces by budding and found in soil and other environmental areas, especially those contaminated by pigeon droppings. Humans and animals acquire infection after inhalation of aerosolized spores. Condition or factors that predispose to cryptococcosis include corticosteroid therapy, lymphoreticular malignancies, HIV infection, and sarcoidosis etc. We discribed a case of cryptococcosis involving lung and CNS coincidently without specific underlying disease and the literature on subject were reviewed. A fifty-six year-old previously healthy female presented with headache of 3 months of duration. She had no history suggesting immunologic suppression and we could not find any abnormal laboratory findings including blood sugar, serum immunoglobulin and complement level, HIV antibody, and T cell subsets. Chest roentgenogram and CT scan showed a solitary soft tissue mass in LUL with distal pneumonitis. Brain MRI showed granulomatous lesion in cerebellum and parasagittal cortex of right frontal lobe. The diagnosis was made by bronchoscopic brushing cytology, transthoracic fine needle aspiration, and sputum KOH mount and culture. She was treated 6 weeks course of Amphotericin B and switched to oral fluconazole therapy for 3 months. Her symptoms and X-ray findings were improved gradually and she is now under regular clinical follow up.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.277-281
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• 2008

HIV affects many organ systems. Patients with HIV infection have substantially increased risk of developing various cancers, primarily by opportunistic infection with oncogenic viruses due to their immunocompromised status. However, extensive evidence also indicates that the viral protein, Tat itself, may playas a major factor in the development of AIDS-related neoplasms. The molecular mechanism underlying Tat's oncogenic activity may include deregulation of cellular genes. Therefore, in this study, we examined the effect of HIV-l Tat on CD99 as one of the target cellular genes, which is a well-known tumor marker in several cancers. By using established HeLa clones that are stably expressing Tat, we found that CD99 is upregulated by endogenous Tat, whereas STAT3 is down regulated. Upon the screening of genes differentially expressed between Tat-stable cells and the control cells by using the gene fishing technique, DEG, we detected 3 genes which expression is affected by the presence of Tat. Furthermore, the methylation specific PCR analysis of the stably Tat expressing cell lines revealed that the CD99 promoter is de methylated in the presence of Tat. Taken together, these results open a potential role of CD99 in AIDS-related oncogenesis via epigenetic regulation by HIV-1 Tat.

• Pediatric Infection and Vaccine
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• v.18 no.2
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• pp.201-206
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• 2011

Purpose : Bacteremia is one of the most common causes of morbidity and mortality in children with cancer. The aim of this study was to evaluate the clinical features of bacteremia in pediatric cancer patients. Methods : We retrospectively analyzed bacteremia episodes occurred in pediatric cancer patients at Samsung Medical Center from January 2008 to December 2010. We excluded bacteremia episodes after hematopoietic stem cell transplantation. Results : A total of 141 blood cultures were positive in 121 patients. Thirteen cultures due to contamination were excluded. For analysis, 128 bacteremia episodes in 108 children were included. Gram-positive organisms accounted for 46.9% (60/ 128) and gram-negative organisms for 53.1% (68/128). The source of bacteremia was identified in 21.1% of episodes. Bacteremia due to catheter related infection was observed in 9.4% of episodes (12/128 episodes) and gram-positive organisms were isolated in 75% of episodes (9/12). There were 10 cases (7.8%) of bacteremia associated with septic shock and gramnegative organisms were isolated in 80% of episodes (8/10). Relapses were documented within 30 days in 2 patients who cleared bacteremia which was confirmed after negative blood cultures. Mortality associated with bacteremia was not observed. Conclusion : Continuous monitoring is needed to maintain the tailored strategies to manage pediatric cancer patients with neutropenic fever who are at high risk of developing bacteremia in each institution.

• Journal of Nutrition and Health
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• v.32 no.8
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• pp.887-896
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• 1999

The purpose of this research is to assess hematological and biochemical status and the prevalence of iron deficiency of pregnant women by gestational age to provide the primary data about iron nutritional status of pregnant women. Pregnant women visiting public health centers in Ulsan participated in study and were divided into 3 trimester by last menstrual period(LMP). Hemoglobin (Hgb), hematocrit(Hct)and mean corpuscular volume(MCV) among iron status indices were not statistically different from normal distribution, however total iron binding capacity(TIBC) and serum ferritin were skewed to left and serum iron and transferrin saturation(TS) were skewed to right. Hgb was positively correlated with Hct(r=0.93, p<0.001) but TIBC was negatively correlated with all indices. Serum ferritin was also correlated with all indices, especially in 3rd trimester but not reached to 1st trimester level. Mean corpuscular hemoglobin(MCH), mean corpuscular hemoglobin concentration(MCHC), Red cell distribution width(RDW), serum iron and TS were not significantly different by trimester, however when serum serum iron was adjusted with hematocrit to correct the hemodilution, it significantly decreased in 2nd trimester. MCV increased in 2nd trimester and was maintained until late pregnancy, TIBC continued to increase throughout the trimester. The prevalence of anemic by CDC(Centers for Disease Control) Hgb criteria(Hgb <11.0g/dl in 1st and 3nd trimester, Hgb<10.5g/dl in 2nd trimester) was 2.8% in 1st trimester, 22.5% in 2nd trimester, 27.1% in 3rd trimester and was similar with prevalence by CDC Hct criteria(Hct < 33% in 1st and 3rd, Hct < 32% in 2nd). The prevalence of anemic of total subjects was 32.7% by WHO criteria(Hgb < 11.0g/dl). Although almost iron status indices increased in 3rd trimester, the prevalence of anemia by different criteria of all indices increased throughout the trimester, so iron nutritional status was considered as serious during late pregnancy. However, since factors other than iron deficiency, such as infection, infection, inflammation, other nutrient deficiency may also play a significant role, to differentiate the anemia due to mainly iron deficiency from the anemia due to other factors, serum ferritin is among the more useful indices in distinguishing the two conditions because it is depressed only in iron deficiency. Hgb<11.0g/dl and serum ferritin<12.0ug/L as the criteria of iron deficiency was suggested by CDC. 17.8% of all subjects were classified as iron deficient anemia, 14.9% as anemic from other reasons, 21.2% as iron deficiency any only 46.2% were in normal iron status.

• Journal of Microbiology and Biotechnology
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• v.28 no.12
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• pp.2133-2140
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• 2018

Norovirus is the most common cause of acute gastroenteritis. Its pathogenesis is poorly understood owing to the difficulty of establishing viral infection in animal models. Here, post-weaning gnotobiotic pigs were infected with human norovirus genogroup II genotype 4 (HuNoV GII.4) to investigate the pathogenesis and replication of the virus. Three groups of four pigs were infected with $1{\times}10^5$, $1{\times}10^6$, or $1{\times}10^7$ genomic equivalent (GE) copies of HuNoV GII.4. Four pigs were used as negative controls. Blood and rectal swab samples were collected after viral infection, and gross legions were examined after necropsy. Diarrhea was induced in 25% and 75% of pigs infected with $1{\times}10^6$ and $1{\times}10^7$ GE copies, respectively. Viral shedding was detected in 50%, 75%, and 50% of pigs infected with $1{\times}10^5$, $1{\times}10^6$, and $1{\times}10^7$ GE copies, respectively. Viremia was detected in 25% of pigs infected with either $1{\times}10^6$ or $1{\times}10^7$ GE copies. When gross lesions of gastroenteritis were investigated, the ileum walls of the infected pigs were thinner than those of the controls. Villi atrophy and inflammatory cell infiltration were identified in the ileum of each infected pig. Viral capsid was identified in the jejunum, ileum, colon, spleen, and mesenteric lymph node. Virus replication was newly verified in the spleen and mesenteric lymph nodes by detection of negative-sense viral RNA. In conclusion, HuNoV GII.4 could induce acute gastroenteritis and replicate in the extra-intestinal lymphoid tissues in post-weaning gnotobiotic pigs. Therefore, such pigs would be a suitable animal model for studying the pathogenesis and replication of HuNoV.

• The Korea Journal of Herbology
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• v.28 no.1
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• pp.59-64
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• 2013

Objectives : Methicillin-Resistant Staphylococcus aureus (MRSA) is a cephalosporin and beta-lactam antibiotic-resistant strains. In most cases, that is spread from infected patients and infection rates are growing increasingly. Thus, accordingly, increased resistance to antibiotics is causing serious problems in the world. Therefore, there is a need to develop alternative antimicrobial drugs for the treatment of infections diseases. Methods : The antibacterial activities of Sinhyowoldosan were evaluated against 3 strains of Methicillin-resistant staphylococcus aureus(MRSA) and 1 standard Methicillin-susceptible S. aureus (MSSA) strain by using the disc diffusion method, minimal inhibitory concentrations (MICs) assay, colorimetric assay using MTT test, checkerboard dilution test and time-kill assay was performed under dark. Results : The MIC (minimum inhibitory concentration) of Sinhyowoldosan water extract against S. aureus strains ranged from 500 to 2,000 ${\mu}g/mL$, so we have confirmed it on a strong antibacterial effect. Also, the combinations of Sinhyowoldosan water extract and conventional antibiotics exhibited improved inhibition of MRSA with synergy effect. We suggest that Sinhyowoldosan water extract against MRSA have antibacterial activity, it has potential as alternatives to antibiotic agent. the combination test was used, Triton X-100 (TX) and DCCD for measurement of membrane permeability and inhibitor of ATPase. As a result, antimicrobial activity of SH is affected by the cell membrane were assessed. Conclusion : We suggest that the Sinhyowoldosan water extract lead the treatment of bacterial infection to solve the resistance and remaining side-effect problems that are the major weak points of traditional antibiotics.

• Biomolecules & Therapeutics
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• v.31 no.3
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• pp.350-358
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• 2023

Hand-foot-and-mouth disease (HFMD) is a viral infectious disease that occurs in children under 5 years of age. Its main causes are coxsackievirus (CV) and enterovirus (EV). Since there are no efficient therapeutics for HFMD, vaccines are effective in preventing the disease. To develop broad coverage against CV and EV, the development of a bivalent vaccine form is needed. The Mongolian gerbil is an efficient and suitable animal model of EV71 C4a and CVA16 infection used to investigate vaccine efficacy following direct immunization. In this study, Mongolian gerbils were immunized with a bivalent inactivated EV71 C4a and inactivated CVA16 vaccine to test their effectiveness against viral infection. Bivalent vaccine immunization resulted in increased Ag-specific IgG antibody production; specifically, EV71 C4a-specific IgG was increased with medium and high doses and CVA16-specific IgG was increased with all doses of immunization. When gene expression of T cell-biased cytokines was analysed, Th1, Th2, and Th17 responses were found to be highly activated in the high-dose immunization group. Moreover, bivalent vaccine immunization mitigated paralytic signs and increased the survival rate following lethal viral challenges. When the viral RNA content was determined from various organs, all three doses of bivalent vaccine immunization were found to significantly decrease viral amplification. Upon histologic examination, EV71 C4a and CVA16 induced tissue damage to the heart and muscle. However, bivalent vaccine immunization alleviated this in a dose-dependent manner. These results suggest that the bivalent inactivated EV71 C4a/CVA16 vaccine could be a safe and effective candidate HFMD vaccine.