• Title/Summary/Keyword: normal flora

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Potential Role of Bacterial Infection in Autoimmune Diseases: A New Aspect of Molecular Mimicry

  • Alam, Jehan;Kim, Yong Chul;Choi, Youngnim
    • IMMUNE NETWORK
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    • v.14 no.1
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    • pp.7-13
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    • 2014
  • Molecular mimicry is an attractive mechanism for triggering autoimmunity. In this review, we explore the potential role of evolutionary conserved bacterial proteins in the production of autoantibodies with focus on granulomatosis with polyangiitis (GPA) and rheumatoid arthritis (RA). Seven autoantigens characterized in GPA and RA were BLASTed against a bacterial protein database. Of the seven autoantigens, proteinase 3, type II collagen, binding immunoglobulin protein, glucose-6-phosphate isomerase, ${\alpha}$-enolase, and heterogeneous nuclear ribonuclear protein have well-conserved bacterial orthologs. Importantly, those bacterial orthologs are also found in human-associated bacteria. The wide distribution of the highly conserved stress proteins or enzymes among the members of the normal flora and common infectious microorganisms raises a new question on how cross-reactive autoantibodies are not produced during the immune response to these bacteria in most healthy people. Understanding the mechanisms that deselect auto-reactive B cell clones during the germinal center reaction to homologous foreign antigens may provide a novel strategy to treat autoimmune diseases.

DENTAL TREATMENT IN A CHILD WITH WISKOTT-ALDRICH SYNDROME : A CASE REPORT (Wiskott-Aldrich syndrome 환아의 치과치료에 관한 임상적 연구)

  • Yang, Cheol-Hee;An, Soo-Hyeon;Rho, Yong-Kwan;Kim, Jae-Gon;Baik, Byeong-Ju
    • Journal of the korean academy of Pediatric Dentistry
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    • v.24 no.1
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    • pp.293-299
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    • 1997
  • Wiskott-Aldrich syndrome is a rare, hereditary disease occurring in males and was first described in 1937. It is characterized by cutaneous eczema, thrombocytopenic purpura and an increased susceptibility to infection due to an immunologic defect. Patients with Wiskott-Aldrich syndrome have a poor antibody response to polysaccharide antigens, low levels of IgM and high levels of IgA and IgE in serum. Oral manifestations of Wiskott-Aldrich syndrome was observed a spontaneous gingival bleeding, palatal petechiae, ulcer and gingival hyperplasia. We report on dental treatment of a 5 years old boy with severe spontaneous gingival bleeding and ulcer suffered from Wiskott-Aldrich syndrome. Prophylactic antibiotics to prevent infection and all potential measures including platelet concentrate therapy to prevent postoperative bleeding should be undertaken. Good oral hygiene should be maintained for prevention of infection by oral normal flora.

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Isolation and Identification of Candida dubliniensis and Distribution of Candida spp. from Oral Cavity of Healthy People

  • Kim, Su Jung
    • Korean Journal of Clinical Laboratory Science
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    • v.45 no.4
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    • pp.144-148
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    • 2013
  • Candida spp. are yeast form fungi, which cause an opportunistic infections in a immune suppressed patients however it is a normal flora of the respiratory system, the gastrointestinal system, and the urogenital system of healthy person. It is investigated that the distribution of Candida spp. cause an oral disease from oral cavity of healthy people and also identified Candia dubliniensis. Distribution and identification of the yeast form fungi in oral cavities of healthy people was investigated by an automatic identifier, VITEK2 system. We found 21 strains of Candida albicans, 3 strains of Candida famata, one strain of Candida tropicalis, Candida haemulonii, Candida krusei, and Candida dubliniensis. In addition, one strain of Cryptococcus spp., Saccharomyces spp., and two unknown strains were isolated. Candida dubliniensis which forms a mass by more than 2 chlamydospores was isolated from a healthy person for the first time. Candida dubliniensis was not grown at $42^{\circ}C$ whereas Candida albicans was grown well. It is known that Candida dubliniencis was isolated in AIDS while it is found in healthy people from this study, which will be helpful to investigate the distribution of Candida spp.

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Infection and Innate Immunityi (감염과 선천면역)

  • Oh, Moo-Young
    • Clinical and Experimental Pediatrics
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    • v.48 no.11
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    • pp.1153-1161
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    • 2005
  • As known by other name(natural immunity), the innate immune system comprises all those mechanisms for dealing with infection that are constitutive or built in, changing little with age or with experience of infection. Though in some ways less sophisticated than adaptive immunity, innate immunity should not belittled, since it has evidently protected thousands of species of invertebrates sufficiently to survive for up to 2 billion years. In the innate immune system, molecules of both cellular and humoral types are involved, corresponding to the need to recognize and dispose of different types of pathogen, to promote inflammatory responses and to interact to the adaptive immune system. A major features of innate immunity are the presence of the normal gut flora, complements, macrophages, dendritic cells, natural killer cells and many cytokines that can block the establishment of infection. Both phagocytic cells and complement system have tremendous potential for damaging host cells, but fortunately they are normally only triggered by foreign materials, and usually most of their destructive effects are focussed on the surface of these or in the safe environment of the phagolysosome. This article addreses the comprehensive mechanisms of the major components of the innate immune system to prevent the infection.

New Insights for Febrile Urinary Tract Infection (Acute Pyelonephritis) in Children

  • Lee, Kyung-Yil
    • Childhood Kidney Diseases
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    • v.20 no.2
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    • pp.37-44
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    • 2016
  • Although asymptomatic bacteriuria, cystitis, and acute pyelonephritis (APN) have been categorized as urinary tract infections (UTIs), the immunopathogenesis of each disease is different. APN shows an age predilection; the majority of children (over 70-80%) with APN are under 1-2 years of age, with a male predominance. After 1-2 years of age, female predominance has been reported. This finding suggests that the immature immune state of infancy may be associated with the pathogenesis of APN. Escherichia coli is the most common etiologic agent; other uropathogens associated with UTIs originate from the host and comprise normal flora that are continuously altered by environmental factors. Therefore, uropathogens may have characteristics different from those of extraneous bacterial pathogens. Although antibiotic-resistant uropathogens, including extended-spectrum beta-lactamase-producing strains, are increasing in Korea and worldwide, treatment failure is rare in immune-competent children. The immunopathogenesis of APN remains unknown. Intact bacteria may not be the causative substances in renal cell injury; rather, smaller substances produced during bacterial replication may be responsible for renal cell injury and scarring. Moreover, substances from host cells such as proinflammatory cytokines may be involved in renal cell injury. A dimercaptosuccinic acid scan is used to detect the site of bacterial replication in the renal parenchyma, and may be influenced by the size of the focus and the stage of APN. Traditional aggressive studies used to identify vesicoureteral reflux after the first episode of APN have been modified because of rare cases of chronic kidney disease in patients with recurrent UTI.

A Case of Pasteurella Multocida Pleural Empyema (Pasteurella Multocida 농흉 1예)

  • Lee, Dong-Yeub;Baek, Seung-Min;Seo, Hyang-Eun;Sohn, Kyung-Rak;Song, Do-Yong;Chung, Byung-Chun;Lee, Byung-Ki;Kim, Won-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.1
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    • pp.111-116
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    • 2000
  • Pasteurella multocida, a Gram-negative coccobacillus, is part of the normal oral flora of many types of animals, including domestic dogs and cats. It is the etiologic agent of a variety of infectious diseases, such as hemorrhagic septicemia in cattle or fowl cholera in chicken. Although this is a primary pathogen in the animal world, infection due to Pasteurella multocida in man has been described with increasing frequency recently. The majority of individuals with Pasteurella multocida pulmonary infection possess some underlying pulmonary diseases, most commonly bronchiectasis or COPD. With a review of literature, We report a young man who developed the empyema caused by Pasteurella multocida.

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Risk Assessment of Growth Hormones and Antimicrobial Residues in Meat

  • Jeong, Sang-Hee;Kang, Dae-Jin;Lim, Myung-Woon;Kang, Chang-Soo;Sung, Ha-Jung
    • Toxicological Research
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    • v.26 no.4
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    • pp.301-313
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    • 2010
  • Growth promoters including hormonal substances and antibiotics are used legally and illegally in food producing animals for the growth promotion of livestock animals. Hormonal substances still under debate in terms of their human health impacts are estradiol-$17\beta$, progesterone, testosterone, zeranol, trenbolone, and melengestrol acetate (MGA). Many of the risk assessment results of natural steroid hormones have presented negligible impacts when they are used under good veterinary practices. For synthetic hormonelike substances, ADIs and MRLs have been established for food safety along with the approval of animal treatment. Small amounts of antibiotics added to feedstuff present growth promotion effects via the prevention of infectious diseases at doses lower than therapeutic dose. The induction of antimicrobial resistant bacteria and the disruption of normal human intestinal flora are major concerns in terms of human health impact. Regulatory guidance such as ADIs and MRLs fully reflect the impact on human gastrointestinal microflora. However, before deciding on any risk management options, risk assessments of antimicrobial resistance require large-scale evidence regarding the relationship between antimicrobial use in food-producing animals and the occurrence of antimicrobial resistance in human pathogens. In this article, the risk profiles of hormonal and antibacterial growth promoters are provided based on recent toxicity and human exposure information, and recommendations for risk management to prevent human health impacts by the use of growth promoters are also presented.

Antibacterial Activity of Some Medicinal Plants against Propionibacterium acnes (여드름 원인균 Propionibacterium acnes에 대한 생약 추출물의 항균활성 측정)

  • Weon, Jin-Bae;Ahn, Ju-Hee;Ma, Choong-Je
    • Korean Journal of Pharmacognosy
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    • v.42 no.1
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    • pp.98-101
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    • 2011
  • Acne, one of the most common skin disease, is a chronic inflammatory disease and is caused by uncertain and multiple factors. Propionibacterium acnes belongs to the human cutaneous normal flora and is a major etiologic agent of acne vulgaris. In this study, we evaluated the antibacterial effect of 19 medicinal plants. Antibacterial activity of extracts prepared from the 19 medicinal plants was investigated against bacteria related to acnes, Propionibacterium acnes. Among them, some medicinal plants inhibited the growth of the P. acnes. Minimum inhibitory concentration (MIC) of Polygonum aviculare (Herb) was 0.2 mg/ml against P. acnes. MIC of Dianthus chinensis (Aerial Part), Forsythia viridissima (Fruit), Lygodium japonicum (Spore) and Sophora flavescens (Root) were 0.4 mg/ml. Based on these results, Polygonum aviculare (Herb), Dianthus chinensis (Aerial Part), Forsythia viridissima (Fruit), Lygodium japonicum (Spore) and Sophora flavescens (Root) may be considered as a candidate for a good medicine for acne.

Comparative Studies of Steel Wool Method and Gaspak Method for the Culture of Anaerobic Bacteria (염기성 세균 배양을 위한 Steel Wool법과 Gaspak법의 비교)

  • 정윤섭
    • Korean Journal of Microbiology
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    • v.12 no.3
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    • pp.131-137
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    • 1974
  • It is a well-known fact that an isolation of non-sporeforming anaerobes, considered normal flora in man ordinarily but causes serious infections sometimes, is a dificult procedure because of their great oxygen sensitivity. Among the many techniques employed in clinical laboratories, despite of its high expenses, the GasPak method has been most widely used because of its relative simplicity. On the other hand, the steel wool method has gained a good reputation recently. This technique makes it possible to treat individual plate so that any single specimen can be promptly cultured anaerobically. The procedure is quite simple and the expenses are negligible. In the present study it is to compare these two methods as to their efficiency of anaerobic cultivation using 13 VPI strains of non-sporeforming amaerobic bacteria. Among the 13 species the following 11, Bacteroides fragilis ss. fragilis, B. fragilis ss. thetaiotaomicron, propionibacterium acnes, Eubacterium limosum, E. lentum, peptococcus asaccharolyticus, Pc. prevotii, Pc. magnus, peptostreptococcus anaerobius, Ps. intermedius nad Veillonella parvula, grew well with the steel wool method whose colony numbers reaching 57 to 119% of those with GasPak method. The remaining two species, Fusobacterium nucleatum and F.necrophorum, did not grow well with the steel wool method showing the colony numbers were only 0.4% of those with GasPak method in the case of Fusobacterium nucleatum. In the case of Fusobacterium necrophorum, very few colonies developed even with a heavy inoculation. As to the size of colonies, there were no significant difference between these two methods.

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A Case of Laryngeal Candidiasis Presented as Laryngeal Leukoplakia (후두백반증으로 발현된 후두 칸디다증 1예)

  • Choi, Ki Yong;Kim, Young Hwan;Myong, Na-Hye;Lee, Sang Joon
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.28 no.1
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    • pp.48-51
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    • 2017
  • Candida exists in the oral cavity as normal flora, which is cultured in 7% of the population. And the development of candidiasis is usually related to the systemic or local immunosuppressed status such as diabetes, long-term antibiotics, steroid, radiation therapy or chemotherapy. However, isolated laryngeal candidiasis in immunocompetent patients is a rare entity with fewer than 40 cases reported in the world. Symptoms of laryngeal candidiasis are variable such as hoarseness, dysphagia, or odynophagia according to its extent, but it has clinical importance because of its resemblance with laryngeal premalignant or malignant lesions. Diagnosis is made by biopsy under direct laryngoscopy with special staining to identify the hyphae. In this article, we report a case of laryngeal candidiasis presented as leukoplakia localized on vocal fold with literature reviews.

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