• Journal of Microbiology
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• v.39 no.3
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• pp.186-194
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• 2001

Scrub typhus, caused by Orientia tsutsugamushi infection, is clinically and histopathologically characterized by local as well as systemic inflammatory reactions, indicating that orientiae induce mechanisms that amplify the inflammatory response. To reveal underlying mechanisms of chemoattraction and activation of responding leukocytes, expression of chemokine and tumor necrosis factor alpha (TNF-$\alpha$) genes in murine peritoneal macrophages after infection with the obligate intracellular bacterium Ο.tsutsugamushi was investigated. The genes that were unregulated included macrophage inflammatory proteins l$\alpha$/$\beta$(MIP-l$\alpha$/$\beta$), MIP-2, monocyte chemoattractant protein 1(MCP-1), RANTES (regulated upon activation, normal T-cell expressed and secreted), gamma-interferon-inducible protein 10(IP-10) and TNF-$\alpha$. Peak expression of these chemokines and TNF-$\alpha$ was observed between 1 and 3 h after infection. These responses returned to or approached baseline preinfection levels 6 h after challenge. Semiquantitative reverse transcription (RT)-PCR analysis revealed dramatic Increases during infection in the steady-state levels of mRNA ceding for the inhibitory subunit of NF-kB (IkB$\alpha$), whose transcription is enhanced by binding of NF-kB within the IkB$\alpha$promoter region. Thus, Ο. tsutsugamushi appears to be a stung inducer of chemokines and TNF-$\alpha$ which may significantly contribute to inflammation and tissue damage observed in scrub typhus by attracting and activating phagocytic leukocytes.

• Food Science of Animal Resources
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• v.30 no.4
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• pp.568-574
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• 2010

This study introduced a chick embryos’ infection model to elucidate the pathogenesis mechanism of Pseudomonas aeruginosa, which causes serious diseases in human after ingestion of P. aeruginosa-contaminated animal originated foods. The embryonic chick model is able to give a rapid and relatively inexpensive method to assess bacterial pathogenicity compared to embryos of other vertebrates. Embryos were infected with P. aeruginosa and elastase-deficient P. aeruginosa. After infection with P. aeruginosa cells, total bacterial cell numbers and gelatinase activities in the embryos were compared. Thereafter, precartilage condensation and chondrogenesis were assessed by peanut agglutinin (PNA) binding on day 3 and by Alcian blue staining for sulfated proteoglycans on day 5, respectively. P. aeruginosa significantly increased in embryos, resulting in abnormal limb development, whereas P. aeruginosa defective in elastase activity partly impaired proliferation. In addition, P. aeruginosa-infected chick embryos significantly stimulated the production of matrix metalloproteinases. Several analyses showed that elevated proteases suppressed the proliferation and survival of chondrogenic cells. The results show that this infection model was a useful assay to determine the virulence mechanism of P. aeruginosa in human after intake of microbiologically contaminated foods.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.8 no.2
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• pp.134-138
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• 2012

In treatment of dentigerous cyst, complete enucleation, histopathologic examination and postoperative care are important to prevent the potential complications (mural ameloblastoma, squamous cell carcinoma). On the other hand, a maxillary impacted supernumerary anterior tooth are removed surgically, owing to the possibility of the cyst formation in future. After the cyst enucleation and extraction of the involved tooth, the wound area sutured and removable resin plate is then applied. In this operation, the postoperative bleeding and infection is likely to occur owing to postoperative accumulation of hematoma & seroma, psychologic stress and other contaminated factor. So, the authors established the immediate rubber & iodoform gauze drainage into the sutured wound of cyst enucleation & tooth extraction for the prevention of postoperative bleeding and infection. The removable resin splint are not used because of the poor cooperation and economic factor. The results were more favorable without the postoperative bleeding & wound infection in a cerebral palsy patient.

• Parasites, Hosts and Diseases
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• v.50 no.4
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• pp.281-286
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• 2012

Helminthic infections afflict over 1.5 billion people worldwide, while Mycobacterium tuberculosis infects one third of the world's population, resulting in 2 million deaths per year. Although tuberculosis and helminthic infections coexist in many parts of the world, and it has been demonstrated that the T-helper 2 and T-regulatory cell responses elicited by helminths can affect the ability of the host to control mycobacterial infection, it is still unclear whether helminth infections in fact affect tuberculosis disease. In this review article, current progress in the knowledge about the immunomodulation induced by helminths to diminish the protective immune responses to bacille Calmette-Guerin vaccination is reviewed, and the knowledge about the types of immune responses modulated by helminths and the consequences for tuberculosis are summarized. In addition, recent data supporting the significant reduction of both M. tuberculosis antigen-specific Toll-like receptor (TLR) 2 and TLR9 expression, and pro-inflammatory cytokine responses to TLR2 and TLR9 ligands in individuals with M. tuberculosis and helminth co-infection were discussed. This examination will allow to improve understanding of the immune responses to mycobacterial infection and also be of great relevance in combating human tuberculosis.

• Preventive Nutrition and Food Science
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• v.10 no.2
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• pp.161-166
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• 2005

We investigated the effect of pycnogenol (PYC) supplementation on retarding the immune dysfunction of CS7BL/6 mice after murine AIDS (MAIDS) development. Dysfunction of T and B cell mitogenesis from primary cultured splenocytes has been observed with retrovirus infection and PYC supplementation partially recovered the dysfunction of T and B cells. There was an abnormal shift of cytokine pattern with retrovirns infection, which was designated by the decreased secretion of Th1 cytokines and increased secretion of Th2 cytokines. PYC supplementation increased IL-2 and $IFN-\gamma$ secretion and decreased IL-4, IL-6, and $TNF-\alpha$ secretion, but it was not sufficient enough to maintain the normal level of these cytokines. Hepatic vitamin E level was significantly decreased by retrovirns infection, in accordance with increased hepatic lipid peroxidation level, whereas PYC supplementation normalized the hepatic level of vitamin E and lipid peroxidation. This study suggests that PYC supplementation may partially help retard the incidence of symptoms during MAIDS.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.3
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• pp.279-285
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• 2001

Although only a minority of the infected individuals develops atrophic gastritis and the malignancy, factors governing clinical outcomes subsequent to Helicobacter pylori (H. pylori) infection have not yet been defined. H. pylori infection is characterized by extensive infiltration of neutrophils. Myeloperoxidase (MPO) in neutrophils amplifies the oxidative potential of hydrogen peroxides that induce gastric mucosal damage, thus MPO is suspected to play a role in H. pylori-induced gastric injury. Therefore, we explored the association of host MPO genetic polymorphism with atrophic gastritis upon H. pylori infection. Biopsy specimens taken from the gastric mucosa were examined histologically in 87 patients. The PCR-RFLP assay was used to characterize MPO genotypes. The distributions of MPO genotypes were MPO (G/G) 82% and MPO (G/A) 18%. None of MPO (A/A) genotype was observed. A strong positive correlation between the levels of neutrophil infiltration and gastric atrophy found only in MPO (G/G) but not in MPO (G/A) genotype. These results suggest that MPO genotype is a critical determinant in the pathogenesis of atrophic gastritis subsequent to H. pylori infection. Further works need to clarify the functional relevance of MPO genetic polymorphisms on gastric cell injury.

• Korean Journal of Veterinary Service
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• v.44 no.1
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• pp.35-43
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• 2021

Rabbit infectious hemorrhagic fever has been reported in rabbits worldwide. The disease is also frequently reported on Korean rabbit farms, and the pathological study of 9 rabbits on such disease-occurring farms was attempted to identify the pathogen. Clinical signs were torticollis and ear ulceration. Most rabbit died with bloody nasal discharges. At necropsy, multiple hemorrhages and inflammation were observed in heart, lung, liver and uterus. The main histopathologic features were hemorrhagic suppurative meningoencephalitis, fibrinous bronchointerstitial pneumonia, bacteremia, liver cell necrosis, multifocal hemorrhages in kidney and disseminated intravascular coagulopathy. The viral VP60 gene of RHDV was identified by Reverse Transcriptase PCR. Pasteurella multocida organisms were cultured, identified by biochemical test and serotyped as A by multiplex capsular typing PCR. In conclusion, the fatal hemorrhagic disease was due to combined infection with both RHDV and P. multocida in rabbits. To our knowledge, this is the first case report about co-infection with both RHDV and P. multocida in rabbits in Korea.

• IMMUNE NETWORK
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• v.22 no.4
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• pp.32.1-32.20
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• 2022

Sjögren syndrome (SS) is a chronic autoimmune disorder that primarily targets the salivary and lacrimal glands. The pathology of these exocrine glands is characterized by periductal focal lymphocytic infiltrates, and both T cell-mediated tissue injury and autoantibodies that interfere with the secretion process underlie glandular hypofunction. In addition to these adaptive mechanisms, multiple innate immune pathways are dysregulated, particularly in the salivary gland epithelium. Our understanding of the pathogenetic mechanisms of SS has substantially improved during the past decade. In contrast to viral infection, bacterial infection has never been considered in the pathogenesis of SS. In this review, oral dysbiosis associated with SS and evidence for bacterial infection of the salivary glands in SS were reviewed. In addition, the potential contributions of bacterial infection to innate activation of ductal epithelial cells, plasmacytoid dendritic cells, and B cells and to the breach of tolerance via bystander activation of autoreactive T cells and molecular mimicry were discussed. The added roles of bacteria may extend our understanding of the pathogenetic mechanisms and therapeutic approaches for this autoimmune exocrinopathy.

• KSBB Journal
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• v.22 no.5
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• pp.282-287
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• 2007

The antiviral mechanism of KT5720 is known to inhibit the cAMP-dependent protein kinase (PKA), on the VSV infection in BHK-21 cell cultures. The virus inducted CPE (cell rounding) was almost completely suppressed by KT5720 at 5 uM. The inhibitor, however, did not affect the replication of the virus and the synthesis of viral macromolecules. Immunological studies showed the viral matrix (M) protein displayed intimate association with the cytoskeletal components and probably the cell rounding. KT5720, did not block the cytoskeletal disruption, while the cell rounding was suppressed. These observations suggest that the interaction between the viral M protein and the cytoskeletal components may not be enough to cause the morphological change of the cell. And, the KT5720-sensitive function may be involved in developing the VSV-induced CPE, but not essential for the virus replications.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.80-80
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• 1993

(목적) 본 연구에서 사용된 바이러스는 HIV-1 nef유전자가 일부 삭제되고 대신 Chloramphenicol acetyltransferase(CAT)가 pSVCAT recombinant 바이러스다. 이러한 recombinant 바이러스를 사용하는 이유는 첫째, CAT activity가 매우 민감하므로 바이러스의 복제억제 정도를 정확하게 측정 할 수 있고 둘째, simian immunodeficiency virus(SIV)의 경우 nef 유전가 in vivo에서는 바이러스의 복제에 필수적이므로 HIV가 SIV와 유사한 것으로 미루어 본 연구에서 사용되는 recombinant SVCAT 바이러스가 안전한 것으로 고려되기 때문이다. (방법) 특히 화합물이 HIV-1의 복제에 얼마나 영향이 있는가는 1) 어느정 도의 virus inoculm을 넣었는지 2) 사용하는 cell line 3) 사용한 cell line의 infection kinetics 4) 실험의 지속기간 5) 테스트하는 assay의 sensitivity에 의존한다. 따라서 $10^{5}$ cell의 H9과 sup T1을 24 well plate에 넣고 sup T1 cell line의 경우 3일 후 항 화합물에 의한 syncytia 형성 및 CAT activity의 억제정도를 현재 AIDS drug으로 쓰이고 있는 Zidovudine을 control로 비교 관찰하였다. H9 cell line의 경우 3일 간격으로 media의 3/4을 fresh media로 바꾸어 주고 9일 후 CAT assay를 하였다. 이러한 assay에서 activity를 보이는 화합물을 reverse transcriptase와 P24 ELISA assay를 재확인하였다.다.