• International Journal of Oral Biology
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• v.32 no.3
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• pp.103-107
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• 2007

We hypothesized that plaque-associated bacteria may have a role in maintenance of alveolar bone. To test it, immortalized gingival epithelial HOK-16B cells were co-cultured with live or lysed eight plaque bacterial species and the expression levels of bone morphogenetic protein (BMP)-2 and -4 were examined by real time reverse transcription-polymerase chain reaction. Un-stimulated HOK-16B cells expressed both BMP-2 and -4. Co-culture with plaque bacterial lysates had significant effects on the level of BMP-2 but not on that of BMP-4. Five species including Streptococcus sanguinis, S. gordonii, Veillonella atypica, Porphyromonas gingivalis, and Treponema denticola substantially up-regulated the level of BMP-2. In contrary to the upregulatory effect of lysate, live T. denticola suppressed the expression of BMP-2. In addition, in vitro osteoblastic differentiation assay using C2C12 cells and the conditioned medium of HOK-16B cells confirmed the production of BMPs by gingival epithelial cells and the modulation of BMP expression by the lysates of S. sanguinis and T. denticola. In conclusion, we have shown that plaque bacteria can regulate the expression of BMP-2 by gingival epithelial cells, the physiologic meaning of which needs further investigation.

• Parasites, Hosts and Diseases
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• v.48 no.2
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• pp.157-160
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• 2010

We report here a human case probably mixed-infected with Clonorchis sinensis and Fasciola sp. who was diagnosed by computed tomography (Cn scan, serological findings, and/or fecal examination. The patient was a 43-year-old Korean female and was admitted to Kyung Hee University Hospital with the complaints of fever and abdominal pain. On admission, marked eosinophilia was noted in her peripheral blood. CT scan showed specific lesions for clonorchiasis and fascioliasis in the liver, along with lesions suggestive of amebic abscess. Micro-ELISA revealed positive results for the 2 helminthic infections. Eggs of C. sinensis and trophozoites of Entamoeba histo/ytica were observed in the stool. Treatment with praziquantel followed by metronidazole and tinidazole reduced abnormalities in the liver and eosinophilia. This is the first case report of a possible co-infection with 2 kinds of liver flukes in the Republic of Korea.

• The Journal of the Korean Society for Microbiology
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• v.35 no.1
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• pp.41-48
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• 2000

Bacteroides fragilis and Escherichia coli, normal colonic inhabitants, are the most frequently isolated bacteria in infected tissues, particularly in intraabdominal abscesses. This study was designed to determine whether enteric bacteria may alter the B. fragilis-induced expression of pro inflammatory cytokines in mouse peritoneal tissue (MPT). After C57BL/6 mice were inoculated with abscess-forming mixture containing B. fragilis in the presence or absence of E. coli, RNA was extracted from MPT. Expression of interleukin (IL)-$1{\alpha}$ and tumor necrosis factor $(TNF){\alpha}$ mRNA was assessed using RT-PCR and standard RNA. Each cytokine protein was also measured by ELISA. The co-inoculation of E. coli into mouse peritoneal cavity advanced the onset of abscess development by B. fragilis infection. When mouse was co-infected with E. coli and B. fragilis intraperitoneally, there was a synergistic increase in the expression of IL-$1{\alpha}$ and $TNF{\alpha}$ mRNA in MPT and this was paralleled by increased cytokine protein secretion. Mixed inoculation of heat-killed E. coli and B. fragilis did not cause a synergistic increase in those cytokine mRNA expression. These results suggest that enteric bacteria may significantly affect proinflammatory cytokine signal produced by host peritoneal cavity in response to B. fragilis infection.

• Preventive Nutrition and Food Science
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• v.21 no.3
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• pp.197-201
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• 2016

Helicobacter pylori infection is associated with an increased risk of developing upper gastrointestinal tract diseases. However, treatment failure is a major cause of concern mainly due to possible recurrence of infection, the side effects, and resistance to antibiotics. The aim of this study was to investigate the activities of Centella asiatica leaf extract (CAE) against H. pylori both in vitro and in vivo. The minimum inhibitory concentrations (MICs) against 55 clinically isolated strains of H. pylori were tested using an agar dilution method. The MICs of CAE ranged from 0.125 mg/mL to 8 mg/mL, effectiveness in inhibiting H. pylori growth was 2 mg/mL. The anti-H. pylori effects of CAE in vivo were also examined in H. pylori-infected C57BL/6 mice. CAE was orally administrated once daily for 3 weeks at doses of 50 mg/kg and 250 mg/kg. CAE at the 50 mg/kg dose significantly reduced H. pylori colonization in mice gastric mucosa. Our study provides novel insights into the therapeutic effects of CAE against H. pylori infection, and it suggests that CAE may be useful as an alternative therapy.

• Journal of Life Science
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• v.17 no.6 s.86
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• pp.766-771
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• 2007

The co-infection with hepatitis B virus (HBV) and hepatitis C Virus (HCV) is associated with a more severe liver disease and increased frequency in the development of hepatocellular carcinoma com-pared to those with single infection. Here, we demonstrated that HBV X protein (HBx) and HCV Core cooperatively up-regulated the level of p53 in human hepatoma HepG2 cells. The elevated p53 subsequently stimulated the expression of proapoptotic Bax whereas it repressed the expression of antiapoptotic Bcl2. These effects, however, were not observed in p53-negative Hep3B cells. Consistently to their cooperative regulation of apoptotic effectors, HBx and HCV Core additively stimulated cisplatin-mediated apoptotic cell death of HepG2 but not of Hep3B cells. These results may help to explain the development of a more severe liver disease in patients co-infection with HBV and HCV as well as some contradictory results on the roles of HBx and Core in apoptosis.

• Journal of The Korea Institute of Healthcare Architecture
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• v.29 no.4
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• pp.37-44
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• 2023

Purpose: Currently, research on environmental conditions and finishing materials for medical facilities with proven antiviral performance is poor in Korea. Through this study, we have explored environmental characteristics and finishing materials that can be used to control cross-infection when constructing medical facilities. Methods: Experiments in overseas papers related to antiviral effects of environmental conditions, spatial compartments, and interior finishes have been analyzed. Results: The higher the temperature, the higher the humidity, and the higher the illuminance of sunlight, the lower the viability of the corona-virus. The proliferation of viruses was suppressed on the surface of the copper alloy. Materials such as brushed steel are the ones that maintain the strongest viability. Among the characteristics of the surface, survival and propagation power differ depending on whether it is porous or hydrophilic. In the case of infection ward actually operated in Italy, the presence of airborne viruses in contaminated and non-contaminated spaces differed significantly. Corona-virus has been identified in reachable parts such as door handles and medical shelves in quasi-contaminated spaces, which are spaces between contaminated and non-contaminated spaces, but the corona-virus has not been identified in cases of out-of-touch walls. Implications: It is necessary to evaluate the performance by testing the construction finishing materials of infection control facilities according to domestic conditions.

• Journal of Veterinary Science
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• v.22 no.1
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• pp.12.1-12.11
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• 2021

Background: Bats have been considered natural reservoirs for several pathogenic human coronaviruses (CoVs) in the last two decades. Recently, a bat CoV was detected in the Republic of Korea; its entire genome was sequenced and reported to be genetically similar to that of the severe acute respiratory syndrome CoV (SARS-CoV). Objectives: The objective of this study was to compare the genetic sequences of SARS-CoV, SARS-CoV-2, and the two Korean bat CoV strains 16BO133 and B15-21, to estimate the likelihood of an interaction between the Korean bat CoVs and the human angiotensin-converting enzyme 2 (ACE2) receptor. Methods: The phylogenetic analysis was conducted with the maximum-likelihood (ML) method using MEGA 7 software. The Korean bat CoVs receptor binding domain (RBD) of the spike protein was analyzed by comparative homology modeling using the SWISS-MODEL server. The binding energies of the complexes were calculated using PRODIGY and MM/GBGA. Results: Phylogenetic analyses of the entire RNA-dependent RNA polymerase, spike regions, and the complete genome revealed that the Korean CoVs, along with SARS-CoV and SARS-CoV-2, belong to the subgenus Sarbecovirus, within BetaCoVs. However, the two Korean CoVs were distinct from SARS-CoV-2. Specifically, the spike gene of the Korean CoVs, which is involved in host infection, differed from that of SARS-CoV-2, showing only 66.8%-67.0% nucleotide homology and presented deletions within the RBD, particularly within regions critical for cross-species transmission and that mediate interaction with ACE2. Binding free energy calculation revealed that the binding affinity of Korean bat CoV RBD to hACE2 was drastically lower than that of SARS-CoV and SARS-CoV-2. Conclusions: These results suggest that Korean bat CoVs are unlikely to bind to the human ACE2 receptor.

• Journal of Chest Surgery
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• v.11 no.4
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• pp.516-522
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• 1978

In spite of recent improvement of the medical and surgical treatments, there are many significant problems in the management of thoracic empyema. This is a clinical analysis of 49 cases of thoracic empyema who underwent lung decortication for a period of 6 years and 5 months extending from May, 1972 to Aug. 1975. The following results were obtained: Male to female ratio was 2. S to 1. The age ranged between Sand 69, bnt was mostly 2r.d and 5th decade. The underlying diseases were pulmonary tuberculosis (30 cases, 61. 1 SO, , ), posttraumatic hemothorax (7 cases, 14.396). pneumonia (6 cases, 12.2%), lung abscess (2 cases, 4.2%), paragonimiasis (2 cases, 4.2%). spontaneous pneumothorax (1 case, 2.1%), and unknown origin (1 case, 2.1%). In 13 cases (26.5%), positive bacterial growth on culture was reported. There were single infection in 11 cases and mixed infection in 2 cases. The organisms grown were Staphylococcus, alpha-hemolytIc Streptococcus, Alkaligenes fecalis, Escherichia coli, Pseudomonas, SerratIa, Enterobacter agglomerans, and Enterococcus in order of frequency. Staphylococcus, Streptococcus, and Serratia were sensitive to several different kinds of antibiotics. But Pseudomonas, Escherichia co:i, and Enterococcus were sensitive to only one or two antibiotics. Leukocytosis was observed In acute empyema, but not in chronic empyema. Hemoglobin and hematocrit were all within normal limits. Preoperative liver function tests were within normal limits in most of the cases. In 49 cases, lung decortication alone was performed in 40 cases (S1. 696), and for the remaining 9 cases (1S. 4%), additional surgical procedures were necessary, i. e., lobectomy (6cases). partial thoracoplasty (2 cases), and lobectomy & partial thoracoplasty (1 cases). The results of lung decortication in thoracic empyema were goed. 38 cases (77.5%) healed with no complication, and 10 cases (20.4%) were complicated by bleeding, wownd infection, pleural infection, chondritis, and psychosis. These complications resolved ultimately leaving no sequelae. One death was recorded (2.1%), and the causes of death were postoperative pleural infection, sepsis and hepatic insufficiency.

• Parasites, Hosts and Diseases
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• v.47 no.2
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• pp.117-124
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• 2009

Toxoplasma gondii provokes rapid and sustained nuclear translocation of the signal transducer and activator of transcription 6 (STAT6) in HeLa cells. We observed activation of STAT6 as early as 2hr after infection with T. gondii by the nuclear translocation of fluorescence expressed from exogenously transfected pDsRed2-STAT6 plasmid and by the detection of phosphotyrosine-STAT6 in Western blot. STAT6 activation occurred only by infection with live tachyzoites but not by co-culture with killed tachyzoites or soluble T. gondii extracts. STAT6 phosphorylation was inhibited by small interfering RNA of STAT6 (siSTAT6). In view of the fact that STAT6 is a central mediator of IL-4 induced gene expression, activation of STAT6 by T. gondii infection resembles that infected host cells has been stimulated by IL-4 treatment. STAT1 was affected to increase the transcription and expression by the treatment of siSTAT6. STAT6 activation was not affected by any excess SOCS's whereas that with IL-4 was inhibited by SOCS-1 and SOCS-3. T. gondii infection induced Eotaxin-3 gene expression which was reduced by $IFN-{\gamma}$. These results demonstrate that T. gondii exploits host STAT6 to take away various harmful reactions by $IFN-{\gamma}$. This shows, for the first time, IL-4-like action by T. gondii infection modulates microbicidal action by $IFN-{\gamma}$ in infected cells.

• Journal of Veterinary Science
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• v.22 no.6
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• pp.67.1-67.7
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• 2021

Background: Chlamydophila felis, formerly known as Chlamydia psittaci var. felis, is frequently associated with ocular, respiratory, and occasionally reproduction tract infections. Even though the infection is sometimes asymptomatic, it potentially results in a latent immunosuppressive infection. Objective: This study aimed to identify occurrences of feline chlamydophilosis, rarely reported in cats in Indonesia. Methods: The observation was conducted in three cats with clinical signs of Cp. felis infection, particularly relapsing conjunctivitis. The cats' histories were recorded based on owners' information. Conjunctival swabs were sampled for cytology examination and molecular assay detection. A phylogenetic tree was generated using MEGA-X software to reveal group clustering. A post-mortem examination was performed on the cat that died during an examination. Results: Cp. felis was detected in both cytological examination and polymerase chain reaction assay. The phylogenetic tree demonstrated that the Cp. felis isolated in this study clustered with several other isolates from the other countries. Cp. felis can be isolated from cats with different clinical manifestations and levels of severity. The chronic fatal infection demonstrated interstitial broncho-pneumonia under histopathological examination. Conclusions: Molecular assay of Cp. felis is always recommended to obtain a definitive diagnosis of feline chlamydophilosis since the disease can have various clinical manifestations. Even though it may be subclinical and is often not fatal, an infected cat may be a carrier that could spread the pathogen in the surrounding environment. Serious disease management is suggested to avoid high costs associated with regularly relapsing disease.