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Sangolli MN, Kugaji MS, Ray SK, Bhat KG. Evaluation of loop-mediated isothermal amplification method for efficient detection of the periodontopathic bacteria Porphyromonas gingivalis. J Indian Soc Periodontol 2024; 28:122-128. [PMID: 38988957 PMCID: PMC11232805 DOI: 10.4103/jisp.jisp_260_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 04/13/2024] [Accepted: 04/18/2024] [Indexed: 07/12/2024] Open
Abstract
Background Periodontitis is a multifactorial, polymicrobial oral inflammatory illness brought on by oral pathogens. Porphyromonas gingivalis is a Gram-negative, obligatory anaerobic, black-pigmented coccobacillus and is regarded as a primary etiological factor in the progression of periodontitis. Rapid, highly senstitive and specific detection methods are emerging. The present study aimed to evaluate the loop-mediated isothermal amplification (LAMP) technique for efficiently detecting P. gingivalis from subgingival plaque samples of chronic periodontitis patients. Materials and Methods This study included 50 subgingival plaque samples from patients suffering from chronic periodontitis. The DNA (Deoxyribonucleic acid) was extracted by the "modified proteinase K" method. A set of six primers, targeting the pepO gene of P. gingivalis, was used for conducting LAMP. The amplification was visualized by naked-eye detection and agarose electrophoresis. Conventional polymerase chain reaction (PCR) and real-time qantitative PCR (qPCR) were carried out by targeting the 16SrRNA (16S ribosomal ribonucleic acid) gene of P. gingivalis. Results The results showed that LAMP detected P. gingivalis in 40 out of 50 samples (80%). Whereas, qPCR and conventional PCR technique detected P. gingivalis in 38 (76%) and 33 (66%) samples respectively. The sensitivity and specificity of the LAMP method were 94.87% and 90.90%, respectively. With qPCR, the sensitivity and specificity were found to be 92.30% and 81.81%, respectively, whereas, with conventional PCR, it was found to be 76.92% and 72.72%, respectively. Conclusion LAMP is an efficient technique for quick, accurate, and reliable identification of P. gingivalis from subgingival plaque samples. The technique needs to be validated analytically, and further studies can be conducted by taking saliva and/or gingival crevicular fluid samples from periodontitis patients.
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Affiliation(s)
- Meenaz N. Sangolli
- Central Research Laboratory, Maratha Mandal’s Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre, Belagavi, Karnataka, India
| | - Manohar S. Kugaji
- Centre for Advanced Medical Research, Shri B. M. Patil Medical College, BLDE (Deemed to be University), Vijayapura, Karnataka, India
| | - Suman Kumar Ray
- Central Research Laboratory, Maratha Mandal’s Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre, Belagavi, Karnataka, India
| | - Kishore G. Bhat
- Central Research Laboratory, Maratha Mandal’s Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre, Belagavi, Karnataka, India
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Salhi L, Rijkschroeff P, Van Hede D, Laine ML, Teughels W, Sakalihasan N, Lambert F. Blood Biomarkers and Serologic Immunological Profiles Related to Periodontitis in Abdominal Aortic Aneurysm Patients. Front Cell Infect Microbiol 2022; 11:766462. [PMID: 35096635 PMCID: PMC8798408 DOI: 10.3389/fcimb.2021.766462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 12/20/2021] [Indexed: 11/13/2022] Open
Abstract
Background Periodontitis is a chronic inflammatory gum disease associated with systemic diseases such as cardiovascular diseases. Aim To investigate the association of systemic blood biomarkers, C-reactive protein (CRP), levels of lipopolysaccharide (LPS), and IgG levels against periodontal pathogens Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) with the stability, based on the aortic diameter, the growth rate and the eligibility for surgical intervention, of patients with abdominal aortic aneurysm (AAA). Methods Patients with stable AAA (n = 30) and unstable AAA (n = 31) were recruited. The anti-A. actinomycetemcomitans and anti-P. gingivalis IgG levels were analyzed by ELISA, the LPS analysis was performed by using the limulus amebocyte lysate (LAL) test, and plasma levels of CRP were determined using an immune turbidimetric method. The association between these blood systemic biomarkers, AAA features, periodontal clinical parameters and oral microbial profiles were explored. Regression models were used to test the relationship between variables. Results The presence of antibodies against Pg and Aa, LPS and high CRP concentrations were found in all AAA patients. The IgG levels were similar in patients with stable and unstable AAA (both for Aa and Pg). Among investigated blood biomarkers, only CRP was associated with AAA stability. The amount of LPS in saliva, supra, and subgingival plaque were significantly associated with the systemic LPS (p <0.05). Conclusions This post-hoc study emphasizes the presence of antibodies against Pg and Aa, LPS and high CRP concentrations in all AAA patients. The presence of Pg in saliva and subgingival plaque was significantly associated with the blood LPS levels. For further studies investigating periodontitis and systemic diseases, specific predictive blood biomarkers should be considered instead of the use of antibodies alone.
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Affiliation(s)
- Leila Salhi
- Department of Periodontology, Buccal Surgery and Implantology, Faculty of Medicine, Liège, Belgium
- *Correspondence: Leila Salhi, ; orcid.org/0000-0003-3529-8452
| | - Patrick Rijkschroeff
- Department of Periodontology , Academic Centre for Dentistry Amsterdam, Vrije Universiteit (VU) Amsterdam, Amsterdam, Netherlands
| | - Dorien Van Hede
- Department of Periodontology, Buccal Surgery and Implantology, Faculty of Medicine, Liège, Belgium
| | - Marja L. Laine
- Department of Periodontology , Academic Centre for Dentistry Amsterdam, Vrije Universiteit (VU) Amsterdam, Amsterdam, Netherlands
| | - Wim Teughels
- Department of Oral Health Sciences, KU Leuven & Dentistry, University Hospitals Leuven, Leuven, Belgium
| | - Natzi Sakalihasan
- Department of Cardiovascular and Thoracic Surgery, Faculty of Medicine, Liège, Belgium
| | - France Lambert
- Department of Periodontology, Buccal Surgery and Implantology, Faculty of Medicine, Liège, Belgium
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Neilands J, Kinnby B. Porphyromonas gingivalis initiates coagulation and secretes polyphosphates - A mechanism for sustaining chronic inflammation? Microb Pathog 2020; 162:104648. [PMID: 33242642 DOI: 10.1016/j.micpath.2020.104648] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/05/2020] [Accepted: 11/19/2020] [Indexed: 01/12/2023]
Abstract
BACKGROUND Periodontitis is a chronic inflammation resulting in destruction of tooth-supporting bone. Chronic inflammation is characterized by extravascular fibrin deposition. Fibrin is central to destruction of bone; monocytes bind to fibrin and form osteoclasts, thus providing a link between coagulation and the tissue destructive processes in periodontitis. The oral microbiome is essential to oral health. However, local ecological changes, such as increased biofilm formation, result in a dysbiotic microbiome characterized by an increase of protease-producing species e.g. Porphyromonas gingivalis. Proteases initiate inflammation and may cleave coagulation factors. Polyphosphates (polyP) may also provide bacteria with procoagulant properties similar to platelet-released polyP. P. gingivalis has also been found in remote locations related to vascular pathology and Alzheimer's disease. OBJECTIVES The aim of this study was to investigate procoagulant activity of ten different species of oral bacteria present in oral health and disease as well as presence of polyP and fibrin formation in planktonic and biofilm bacteria. METHODS Oral bacteria were studied for protease production and procoagulant activity. The presence of polyP and formation of fibrin was observed using confocal microscopy. RESULTS P. gingivalis showed strong protease activity and was the only species exerting procoagulant activity. Confocal microscopy showed polyP intracellularly in planktonic bacteria and extracellularly after biofilm formation. Fibrin formation emanated from planktonic bacteria and from both bacteria and polyP in biofilm cultures. CONCLUSIONS The procoagulant activity of P. gingivalis could explain its role in chronic inflammation, locally in oral tissues as well as in remote locations.
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Affiliation(s)
- Jessica Neilands
- Dept of Oral Biology and Pathology, Faculty of Odontology, Malmö University, Malmö, Sweden
| | - Bertil Kinnby
- Dept of Oral Biology and Pathology, Faculty of Odontology, Malmö University, Malmö, Sweden.
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Abstract
Porphyromonas gingivalis is a key pathogen of periodontitis, a polymicrobial disease characterized by a chronic inflammation that destroys the tissues supporting the teeth. Thus, understanding the virulence potential of P. gingivalis is essential to maintaining a healthy oral microbiome. In nonoral organisms, CRISPR-Cas systems have been shown to modulate a variety of microbial processes, including protection from exogenous nucleic acids, and, more recently, have been implicated in bacterial virulence. Previously, our clinical findings identified activation of the CRISPR-Cas system in patient samples at the transition to disease; however, the mechanism of contribution to disease remained unknown. The importance of the present study resides in that it is becoming increasingly clear that CRISPR-associated proteins have broader functions than initially thought and that those functions now include their role in the virulence of periodontal pathogens. Studying a P. gingivaliscas3 mutant, we demonstrate that at least one of the CRISPR-Cas systems is involved in the regulation of virulence during infection. The CRISPR (clustered regularly interspaced short palindromic repeat)-Cas system is a unique genomic entity that provides prokaryotic cells with adaptive and heritable immunity. Initial studies identified CRISPRs as central elements used by bacteria to protect against foreign nucleic acids; however, emerging evidence points to CRISPR involvement in bacterial virulence. The present study aimed to identify the participation of one CRISPR-Cas protein, Cas3, in the virulence of the oral pathogen Porphyromonas gingivalis, an organism highly associated with periodontitis. Our results show that compared to the wild type, a mutant with a deletion of the Cas3 gene, an essential nuclease part of the class 1 type I CRISPR-Cas system, increased the virulence of P. gingivalis. In vitro infection modeling revealed only mildly enhanced production of proinflammatory cytokines by THP-1 cells when infected with the mutant strain. Dual transcriptome sequencing (RNA-seq) analysis of infected THP-1 cells showed an increase in expression of genes associated with pathogenesis in response to Δcas3 mutant infection, with the target of Cas3 activities in neutrophil chemotaxis and gene silencing. The importance of cas3 in controlling virulence was corroborated in a Galleria mellonella infection model, where the presence of the Δcas3 mutant resulted in a statistically significant increase in mortality of G. mellonella. A time-series analysis of transcription patterning during infection showed that G. mellonella elicited very different immune responses to the wild-type and the Δcas3 mutant strains and revealed a rearrangement of association in coexpression networks. Together, these observations show for the first time that Cas3 plays a significant role in regulating the virulence of P. gingivalis. IMPORTANCEPorphyromonas gingivalis is a key pathogen of periodontitis, a polymicrobial disease characterized by a chronic inflammation that destroys the tissues supporting the teeth. Thus, understanding the virulence potential of P. gingivalis is essential to maintaining a healthy oral microbiome. In nonoral organisms, CRISPR-Cas systems have been shown to modulate a variety of microbial processes, including protection from exogenous nucleic acids, and, more recently, have been implicated in bacterial virulence. Previously, our clinical findings identified activation of the CRISPR-Cas system in patient samples at the transition to disease; however, the mechanism of contribution to disease remained unknown. The importance of the present study resides in that it is becoming increasingly clear that CRISPR-associated proteins have broader functions than initially thought and that those functions now include their role in the virulence of periodontal pathogens. Studying a P. gingivaliscas3 mutant, we demonstrate that at least one of the CRISPR-Cas systems is involved in the regulation of virulence during infection.
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Shoji M, Shibata S, Sueyoshi T, Naito M, Nakayama K. Biogenesis of Type V pili. Microbiol Immunol 2020; 64:643-656. [DOI: 10.1111/1348-0421.12838] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/11/2020] [Accepted: 08/13/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Mikio Shoji
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences Nagasaki University Nagasaki Nagasaki Japan
| | - Satoshi Shibata
- Molecular Cryo‐Electron Microscopy Unit Okinawa Institute of Science and Technology Graduate University Onna Okinawa Japan
| | - Takayuki Sueyoshi
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences Nagasaki University Nagasaki Nagasaki Japan
| | - Mariko Naito
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences Nagasaki University Nagasaki Nagasaki Japan
| | - Koji Nakayama
- Department of Microbiology and Oral Infection, Graduate School of Biomedical Sciences Nagasaki University Nagasaki Nagasaki Japan
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Rafiei M, Kiani F, Sayehmiri F, Sayehmiri K, Sheikhi A, Zamanian Azodi M. Study of Porphyromonas gingivalis in periodontal diseases: A systematic review and meta-analysis. Med J Islam Repub Iran 2017; 31:62. [PMID: 29445691 PMCID: PMC5804457 DOI: 10.18869/mjiri.31.62] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Indexed: 12/26/2022] Open
Abstract
Background: The mouth cavity hosts various types of anaerobic bacteria including Porphyromonas gingivalis, which causes periodontal
inflammatory diseases. P. gingivalis is a gram-negative oral anaerobe and is considered as a main etiological factor in periodontal
diseases. Several studies have reported a relationship between P. gingivalis in individuals with periodontal diseases and a critical role of
this bacterium in the pathogenesis of periodontal diseases. The present study aimed at estimating this probability using a meta-analysis.
Methods: We searched several databases including PubMed, Scopus, Google Scholar, and Web of Science to identify case-control
studies addressing the relationship between P. gingivalis with periodontal diseases. A total of 49 reports published from different countries
from 1993 to 2014 were included in this study. I² (heterogeneity index) statistics were calculated to examine heterogeneity. Data
were analyzed using STATA Version 11.
Results: After a detailed analysis of the selected articles, 49 case-control studies with 5924 individuals fulfilled the inclusion criteria
for the meta-analysis. The healthy controls included 2600 healthy individuals with a Mean±SD age of 36.56±7.45 years. The periodontal
diseases group included 3356 patients with a mean age of 43.62±8.35 years. There was a statistically significant difference between P. gingivalis in periodontal patients and healthy controls; 9.24 (95% CI: 5.78 to 14.77; P = 0.000). In the other word, there was a significant
relationship between the presence of P. gingivalis and periodontal diseases.
Conclusion: Analyzing the results of the present study, we found a strong association between the presence of P. gingivalis and periodontal diseases. This result suggests that another research is needed to further assess this subject.
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Affiliation(s)
- Mohammad Rafiei
- Department of Biostatistics and Epidemiology, School of Medicine, Arak University of Medical Sciences, Arak, Iran
| | - Faezeh Kiani
- Student Research Committee, Ilam University of Medical Sciences, Ilam, Iran
| | - Fatemeh Sayehmiri
- Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kourosh Sayehmiri
- Department of Social Medicine, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Abdolkarim Sheikhi
- Department of Immunology and Microbiology, Dezful University of Medical Sciences, Dezful, Iran
| | - Mona Zamanian Azodi
- Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Saraiva L, Rebeis ES, Martins EDS, Sekiguchi RT, Ando-Suguimoto ES, Mafra CES, Holzhausen M, Romito GA, Mayer MPA. IgG sera levels against a subset of periodontopathogens and severity of disease in aggressive periodontitis patients: a cross-sectional study of selected pocket sites. J Clin Periodontol 2014; 41:943-51. [DOI: 10.1111/jcpe.12296] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2014] [Indexed: 12/17/2022]
Affiliation(s)
- Luciana Saraiva
- Department of Periodontology; Dental School; University of São Paulo; São Paulo SP Brazil
| | - Estela S. Rebeis
- Department of Periodontology; Dental School; University of São Paulo; São Paulo SP Brazil
| | - Eder de S. Martins
- Department of Periodontology; Dental School; University of São Paulo; São Paulo SP Brazil
| | - Ricardo T. Sekiguchi
- Department of Periodontology; Dental School; University of São Paulo; São Paulo SP Brazil
| | - Ellen S. Ando-Suguimoto
- Department of Microbiology; Institute of Biomedical Sciences; University of São Paulo; São Paulo SP Brazil
| | | | - Marinella Holzhausen
- Department of Periodontology; Dental School; University of São Paulo; São Paulo SP Brazil
| | - Giuseppe A. Romito
- Department of Periodontology; Dental School; University of São Paulo; São Paulo SP Brazil
| | - Marcia P. A. Mayer
- Department of Microbiology; Institute of Biomedical Sciences; University of São Paulo; São Paulo SP Brazil
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Nonaka M, Shoji M, Kadowaki T, Sato K, Yukitake H, Naito M, Nakayama K. Analysis of a Lys-specific serine endopeptidase secreted via the type IX secretion system in Porphyromonas gingivalis. FEMS Microbiol Lett 2014; 354:60-8. [PMID: 24655155 DOI: 10.1111/1574-6968.12426] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 02/03/2014] [Accepted: 03/13/2014] [Indexed: 11/27/2022] Open
Abstract
Porphyromonas gingivalis, a significant causative agent of adult periodontitis, possesses a novel secretion system called the type IX secretion system (T9SS). A number of virulence factors, such as Arg-gingipain (Rgp), are translocated onto the cell surface and into the extracellular milieu via the T9SS. In this study, we found that the PGN_1416 90- to 120-kDa diffuse protein bands were located in the outer membrane fraction and that the presence of the bands was dependent on genes involved in the T9SS and the formation of anionic lipopolysaccharide (A-LPS). These data strongly suggest that the PGN_1416 protein is secreted by the T9SS and anchored onto the cell surface by binding to A-LPS. Enzymatic analysis using outer membrane fractions suggested that the PGN_1416 protein has a Lys-specific serine endopeptidase activity and that its activation requires processing by Rgp. Homologues of the gene encoding PGN_1416, which is referred to as pepK, were found in bacteria belonging to the phyla Bacteroidetes and Proteobacteria, whereas homologues encoding the C-terminal domain, which is essential for T9SS-mediated secretion, and the catalytic domain were only observed in bacteria belonging to the Bacteroidetes phylum.
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Affiliation(s)
- Minako Nonaka
- Division of Microbiology and Oral Infection, Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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Liu Y, Zhang Y, Wang L, Guo Y, Xiao S. Prevalence of Porphyromonas gingivalis four rag locus genotypes in patients of orthodontic gingivitis and periodontitis. PLoS One 2013; 8:e61028. [PMID: 23593379 PMCID: PMC3617233 DOI: 10.1371/journal.pone.0061028] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Accepted: 03/05/2013] [Indexed: 12/26/2022] Open
Abstract
Porphyromonas gingivalis is considered as a major etiological agent in periodontal diseases and implied to result in gingival inflammation under orthodontic appliance. rag locus is a pathogenicity island found in Porphyromonas gingivalis. Four rag locus variants are different in pathogenicity of Porphyromonas gingivalis. Moreover, there are different racial and geographic differences in distribution of rag locus genotypes. In this study, we assessed the prevalence of Porphyromonas gingivalis and rag locus genotypes in 102 gingival crevicular fluid samples from 57 cases of gingivitis patients with orthodontic appliances, 25 cases of periodontitis patients and 20 cases of periodontally healthy people through a 16S rRNA-based PCR and a multiplex PCR. The correlations between Porphyromona.gingivalis/rag locus and clinical indices were analyzed. The prevalence of Porphyromonas gingivalis and rag locus genes in periodontitis group was the highest among three groups and higher in orthodontic gingivitis than healthy people (p<0.01). An obviously positive correlation was observed between the prevalence of Porphyromonas gingivalis/rag locus and gingival index. rag-3 and rag-4 were the predominant genotypes in the patients of orthodontic gingivitis and mild-to-moderate periodontitis in Shandong. Porphyromonas.gingivalis carrying rag-1 has the strong virulence and could be associated with severe periodontitis.
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Affiliation(s)
- Yi Liu
- Pediatric Research Institute, Qilu Children's Hospital of Shandong University, Ji'nan, Shandong, China
| | - Yujie Zhang
- Department of Orthodontic, Jinan Stomatological Hospital, Jinan, Shandong, China
| | - Lili Wang
- Clinical Laboratory, Jinan Central Hospital of Shandong University, Jinan, Shandong, China
| | - Yang Guo
- Department of Orthodontic, Jinan Stomatological Hospital, Jinan, Shandong, China
| | - Shuiqing Xiao
- Department of Orthodontic, Jinan Stomatological Hospital, Jinan, Shandong, China
- * E-mail:
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Sato K, Yukitake H, Narita Y, Shoji M, Naito M, Nakayama K. Identification ofPorphyromonas gingivalisproteins secreted by the Por secretion system. FEMS Microbiol Lett 2012; 338:68-76. [DOI: 10.1111/1574-6968.12028] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 10/04/2012] [Indexed: 01/19/2023] Open
Affiliation(s)
- Keiko Sato
- Division of Microbiology and Oral Infection; Department of Molecular Microbiology and Immunology; Nagasaki University Graduate School of Biomedical Sciences; Nagasaki; Japan
| | - Hideharu Yukitake
- Division of Microbiology and Oral Infection; Department of Molecular Microbiology and Immunology; Nagasaki University Graduate School of Biomedical Sciences; Nagasaki; Japan
| | - Yuka Narita
- Division of Microbiology and Oral Infection; Department of Molecular Microbiology and Immunology; Nagasaki University Graduate School of Biomedical Sciences; Nagasaki; Japan
| | - Mikio Shoji
- Division of Microbiology and Oral Infection; Department of Molecular Microbiology and Immunology; Nagasaki University Graduate School of Biomedical Sciences; Nagasaki; Japan
| | - Mariko Naito
- Division of Microbiology and Oral Infection; Department of Molecular Microbiology and Immunology; Nagasaki University Graduate School of Biomedical Sciences; Nagasaki; Japan
| | - Koji Nakayama
- Division of Microbiology and Oral Infection; Department of Molecular Microbiology and Immunology; Nagasaki University Graduate School of Biomedical Sciences; Nagasaki; Japan
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