Significance of Normal Oral Flora, Particularly Group Oral Streptococci as Defense Mechanism against Infection in Healthy Dividuals (Normal Defense Mechanism by Oral Streptococcus Group)

1992 ◽  
Vol 66 (12) ◽  
pp. 1634-1638
Author(s):  
Isao FUJIMORI ◽  
Toshihiko YAMADA ◽  
Kazuhiko KIKUSHIMA ◽  
Rei GOTO ◽  
Jun OGINO ◽  
...  
Keyword(s):  
Defense Mechanism ◽  
Oral Streptococci ◽  
Oral Flora ◽  
Streptococcus Group ◽  
Oral Streptococcus ◽  
Normal Defense

scholarly journals Targeting the HUβ Protein PreventsPorphyromonas gingivalisfrom Entering into Preexisting Biofilms

2018 ◽  
Vol 200 (11) ◽  
pp. e00790-17 ◽  
Author(s):  
Christopher J. Rocco ◽  
Lauren O. Bakaletz ◽  
Steven D. Goodman
Keyword(s):  
Oral Cavity ◽  
Periodontal Disease ◽  
Porphyromonas Gingivalis ◽  
The United States ◽  
Extracellular Dna ◽  
Bacterial Biofilms ◽  
Oral Streptococci ◽  
Content Type ◽  
Oral Streptococcus ◽  
Streptococcal Species

ABSTRACTThe oral cavity is home to a wide variety of bacterial species, both commensal, such as various streptococcal species, and pathogenic, such asPorphyromonas gingivalis, one of the main etiological agents of periodontal disease. Our understanding of how these bacteria ultimately cause disease is highly dependent upon understanding how they coexist and interact with one another in biofilm communities and the mechanisms by which biofilms are formed. Our research has demonstrated that the DNABII family of DNA-binding proteins are important components of the extracellular DNA (eDNA)-dependent matrix of bacterial biofilms and that sequestering these proteins via protein-specific antibodies results in the collapse of the biofilm structure and release of the resident bacteria. While the high degree of similarity among the DNABII family of proteins has allowed antibodies derived against specific DNABII proteins to disrupt biofilms formed by a wide range of bacterial pathogens, the DNABII proteins ofP. gingivalishave proven to be antigenically distinct, allowing us to determine if we can use anti-P. gingivalisHUβ antibodies to specifically target this species for removal from a mixed-species biofilm. Importantly, despite forming homotypic biofilmsin vitro,P. gingivalismust enter preexisting biofilmsin vivoin order to persist within the oral cavity. The data presented here indicate that antibodies derived against theP. gingivalisDNABII protein, HUβ, reduce by half the amount ofP. gingivalisorganisms entering into preexisting biofilm formed by four oral streptococcal species. These results support our efforts to develop methods for preventing and treating periodontal disease.IMPORTANCEPeriodontitis is one of the most prevalent chronic infections, affecting 40 to 50% of the population of the United States. The root cause of periodontitis is the presence of bacterial biofilms within the gingival space, withPorphyromonas gingivalisbeing strongly associated with the development of the disease. Periodontitis also increases the risk of secondary conditions and infections such as atherosclerosis and infective endocarditis caused by oral streptococci. To induce periodontitis,P. gingivalisneeds to incorporate into preformed biofilms, with oral streptococci being important binding partners. Our research demonstrates that targeting DNABII proteins with an antibody disperses oral streptococcus biofilm and preventsP. gingivalisentry into oral streptococcus biofilm. These results suggest potential therapeutic treatments for endocarditis caused by streptococci as well as periodontitis.

scholarly journals Production of the Lantibiotic Salivaricin A and Its Variants by Oral Streptococci and Use of a Specific Induction Assay To Detect Their Presence in Human Saliva

2006 ◽  
Vol 72 (2) ◽  
pp. 1459-1466 ◽  
Author(s):  
Philip A. Wescombe ◽  
Mathew Upton ◽  
Karen P. Dierksen ◽  
Nancy L. Ragland ◽  
Senthuran Sivabalan ◽  
...  
Keyword(s):  
Structural Gene ◽  
Micrococcus Luteus ◽  
Human Saliva ◽  
Biologically Active ◽  
Oral Streptococci ◽  
Oral Flora ◽  
Healthy Humans ◽  
Ability To Act ◽  
Biologically Active Peptide

ABSTRACT Salivaricin A (SalA), the first Streptococcus salivarius lantibiotic to be characterized, appears to be inhibitory to most Streptococcus pyogenes strains. A variant of the SalA structural gene (salA1) is present in more than 90% of S. pyogenes strains, but only strains of M serotype 4 and T pattern 4 produce the biologically active peptide. The present study identifies four additional variants (salA2 to salA5) of the SalA structural gene and demonstrates that each of the corresponding inhibitory peptides (SalA2 to SalA5) is produced in vitro. These variants appear to be similar to SalA and SalA1 in their inhibitory activity against Micrococcus luteus and in their ability to act as inducers of SalA production. It had previously been shown that S. pyogenes strain SF370 had a deletion (of approximately 2.5 kb) in the salM and salT genes of the salA1 locus. In the present study, several additional characteristic deletions within the salA1 loci were identified. S. pyogenes strains of the same M serotype all share the same salA1 locus structure. Since S. salivarius is a predominant member of the normal oral flora of healthy humans, strains producing anti-S. pyogenes lantibiotics, such as SalA, may have excellent potential for use as oral probiotics. In the present study, we have used a highly specific SalA induction system to directly detect the presence of SalA in the saliva of humans who either naturally harbor populations of SalA-producing S. salivarius or who have been colonized with the SalA2-producing probiotic S. salivarius K12.

COVID-19 and Diabetes

2021 ◽  
Vol 6 (1) ◽  
Keyword(s):  
Intensive Care ◽  
Blood Sugar ◽  
Intensive Care Units ◽  
Defense Mechanism ◽  
Heart Association ◽  
Low Grade ◽  
Additional Risk ◽  
Risk Of Death ◽  
Constant State ◽  
Normal Defense

COVID-19 is a disease caused by a newly discovered coronavirus which is easily transmitted among humans. One of the reasons for the greater risk of diabetes is that insulin resistance promotes low-grade chronic inflammation, leaving the immune system weakened due to this constant state of alertness. Additional risk factors such as heart disease are often present in people infected with COVID-19 who have diabetes. It is important to point out that controlling blood sugar, before and during infection, can be helpful in fighting infection. Blood sugar control in people with diabetes is a procedure that can prevent certain infections and ensure a normal defense mechanism in response to infection. The COVID-19 pandemic has caused concern around the world, especially in people with certain diseases such as diabetes. Data available to the American Heart Association show that among COVID-19 patients treated in intensive care units, 32 percent have diabetes, and among those hospitalized who are not in intensive care units, 24 percent have diabetes. It is estimated that diabetics have a nearly five times higher risk of death from COVID-19.

scholarly journals PerR-Regulated Manganese Ion Uptake Contributes to Oxidative Stress Defense in an Oral Streptococcus

2014 ◽  
Vol 80 (8) ◽  
pp. 2351-2359 ◽  
Author(s):  
Xinhui Wang ◽  
Huichun Tong ◽  
Xiuzhu Dong
Keyword(s):  
Iron Homeostasis ◽  
Critical Role ◽  
Brain Heart Infusion ◽  
Oral Streptococci ◽  
Content Type ◽  
Manganese Ion ◽  
Gram Positive Bacteria ◽  
Wild Type Phenotype ◽  
Oral Streptococcus ◽  
Antioxidative Stress

ABSTRACTMetal homeostasis plays a critical role in antioxidative stress.Streptococcus oligofermentans, an oral commensal facultative anaerobe lacking catalase activity, produces and tolerates abundant H2O2, whereas Dpr (an Fe2+-chelating protein)-dependent H2O2protection does not confer such high tolerance. Here, we report that inactivation ofperR, a peroxide-responsive repressor that regulates zinc and iron homeostasis in Gram-positive bacteria, increased the survival of H2O2-pulsedS. oligofermentans32-fold and elevated cellular manganese 4.5-fold.perRcomplementation recovered the wild-type phenotype. When grown in 0.1 to 0.25 mM MnCl2,S. oligofermentansincreased survival after H2O2stress 2.5- to 23-fold, and even greater survival was found for theperRmutant, indicating that PerR is involved in Mn2+-mediated H2O2resistance inS. oligofermentans. Mutation ofmntAcould not be obtained in brain heart infusion (BHI) broth (containing ∼0.4 μM Mn2+) unless it was supplemented with ≥2.5 μM MnCl2and caused 82 to 95% reduction of the cellular Mn2+level, whilemntABCoverexpression increased cellular Mn2+2.1- to 4.5-fold. Thus, MntABC was identified as a high-affinity Mn2+transporter inS. oligofermentans. mntAmutation reduced the survival of H2O2-pulsedS. oligofermentans5.7-fold, whilemntABCoverexpression enhanced H2O2-challenged survival 12-fold, indicating that MntABC-mediated Mn2+uptake is pivotal to antioxidative stress inS. oligofermentans. perRmutation or H2O2pulsing upregulatedmntABC, while H2O2-induced upregulation diminished in theperRmutant. This suggests thatperRrepressesmntABCexpression but H2O2can release the suppression. In conclusion, this work demonstrates that PerR regulates manganese homeostasis inS. oligofermentans, which is critical to H2O2stress defenses and may be distributed across all oral streptococci lacking catalase.

scholarly journals Macrophage Polarization Alters Postphagocytosis Survivability of the CommensalStreptococcus gordonii

2017 ◽  
Vol 86 (3) ◽  
Author(s):  
Andrew J. Croft ◽  
Sarah Metcalfe ◽  
Kiyonobu Honma ◽  
Jason G. Kay
Keyword(s):  
Macrophage Polarization ◽  
Oral Bacteria ◽  
Ros Production ◽  
Systemic Diseases ◽  
Oxygen Species ◽  
Oral Streptococci ◽  
Phagocytic Cells ◽  
Content Type ◽  
Systemic Inflammatory Disease ◽  
Oral Streptococcus

ABSTRACTOral streptococci are generally considered commensal organisms; however, they are becoming recognized as important associate pathogens during the development of periodontal disease as well as being associated with several systemic diseases, including as a causative agent of infective endocarditis. An important virulence determinant of these bacteria is an ability to evade destruction by phagocytic cells, yet how this subversion occurs is mostly unknown. UsingStreptococcus gordoniias a model commensal oral streptococcus that is also associated with disease, we find that resistance to reactive oxygen species (ROS) with an active ability to damage phagosomes allows the bacterium to avoid destruction within macrophages. This ability to survive relies not only on the ROS resistance capabilities of the bacterium but also on ROS production by macrophages, with both being required for maximal survival of internalized bacteria. Importantly, we also show that this dependence on ROS production by macrophages for resistance has functional significance:S. gordoniiintracellular survival increases when macrophages are polarized toward an activated (M1) profile, which is known to result in prolonged phagosomal ROS production compared to that of alternatively (M2) polarized macrophages. We additionally find evidence of the bacterium being capable of both delaying the maturation of and damaging phagosomes. Taken together, these results provide essential insights regarding the mechanisms through which normally commensal oral bacteria can contribute to both local and systemic inflammatory disease.

scholarly journals Reduced susceptibility to amoxicillin of oral streptococci following amoxicillin exposure

2009 ◽  
Vol 58 (8) ◽  
pp. 1092-1097 ◽  
Author(s):  
H. Chardin ◽  
K. Yasukawa ◽  
N. Nouacer ◽  
C. Plainvert ◽  
P. Aucouturier ◽  
...  
Keyword(s):  
Short Duration ◽  
Tooth Extraction ◽  
Bacterial Resistance ◽  
Odontogenic Infection ◽  
Oral Streptococci ◽  
Oral Flora ◽  
Clinical Efficiency ◽  
The Impact ◽  
Selection Of

As antibiotic pressure often triggers bacterial resistance, the use of short-duration therapies is increasingly recommended. The objective of the present study was to evaluate both the clinical efficiency and the impact on oral streptococci of a 3 day versus a 7 day amoxicillin therapy for odontogenic infection requiring tooth extraction. On day 0, patients were randomly assigned to a 3 day or 7 day amoxicillin treatment. The tooth was extracted on day 2 and the post-operative follow-up was carried out on day 9. Oral flora was collected on days 0, 9 and 30, and the susceptibility of the streptococci to amoxicillin was determined. The results showed that treatment with amoxicillin for 3 or 7 days had a similar clinical efficiency, and also induced similar selection of oral streptococci with reduced susceptibility to amoxicillin, suggesting that the selection of strains with reduced susceptibility to amoxicillin is a rapid phenomenon, appearing even with short-duration therapies.

scholarly journals Pneumococci Can Become Virulent by Acquiring a New Capsule From Oral Streptococci

2019 ◽  
Vol 222 (3) ◽  
pp. 372-380 ◽  
Author(s):  
Moon H Nahm ◽  
Terry Brissac ◽  
Mogens Kilian ◽  
Jiri Vlach ◽  
Carlos J Orihuela ◽  
...  
Keyword(s):  
Mouse Model ◽  
Capsular Polysaccharide ◽  
World Health ◽  
Oral Streptococci ◽  
Capsule Production ◽  
Pneumococcal Strain ◽  
Oral Streptococcus ◽  
Control And Prevention ◽  
Health Organization

Abstract Pneumococcal conjugate vaccines have been successful, but their use has increased infections by nonvaccine serotypes. Oral streptococci often harbor capsular polysaccharide (PS) synthesis loci (cps). Although this has not been observed in nature, if pneumococcus can replace its cps with oral streptococcal cps, it may increase its serotype repertoire. In the current study, we showed that oral Streptococcus strain SK95 and pneumococcal strain D39 both produce structurally identical capsular PS, and their genetic backgrounds influence the amount of capsule production and shielding from nonspecific killing. SK95 is avirulent in a well-established in vivo mouse model. When acapsular pneumococcus was transformed with SK95 cps, the transformant became virulent and killed all mice. Thus, cps from oral Streptococcus strains can make acapsular pneumococcus virulent, and interspecies cps transfer should be considered a potential mechanism of serotype replacement. Our findings, along with publications from the US Centers for Disease Control and Prevention, highlight potential limitations of the 2013 World Health Organization criterion for studying pneumococcal serotypes carried without isolating bacteria. We show that an oral streptococcal strain, SK95, and a pneumococcal strain, D39, both produce chemically identical capsular PS. We also show that transferring SK95 cps into noncapsulated, avirulent pneumococcus gave it the capacity for virulence in a mouse model.

Antibiotic prophylaxis and prevention of infective endocarditis

ESC CardioMed ◽  
2018 ◽  
pp. 1736-1738
Author(s):  
Bruno Hoen ◽  
Xavier Duval
Keyword(s):  
Infective Endocarditis ◽  
High Risk ◽  
Antibiotic Prophylaxis ◽  
Oral Streptococci ◽  
Efficacy And Safety ◽  
Native Valve ◽  
Oral Flora ◽  
Cardiac Implantable Electronic Devices ◽  
Dental Procedures ◽  
Healthcare Associated

Prevention of infective endocarditis has historically focused on oral health because oral streptococci are part of oral flora and once caused most cases of native valve infective endocarditis. Because no randomized clinical trial has ever been conducted to confirm the efficacy and safety of antibiotic prophylaxis of infective endocarditis, it is likely that the debate on indications for antibiotic prophylaxis of infective endocarditis will continue in the coming years. In the meantime, it is reasonable to propose antibiotic prophylaxis to patients at high risk of infective endocarditis before they undergo high-risk dental procedures. Prevention of healthcare-associated infective endocarditis should also be targeted through prevention of healthcare-acquired bacteraemia, and antibiotic prophylaxis before the implantation of cardiac implantable electronic devices. Other prevention options include preservation of good oral hygiene. In the future, prevention of Staphylococcus aureus endocarditis might rely on vaccines, with candidate S. aureus vaccines currently being evaluated in humans.

scholarly journals Evaluation of the Anti-Inflammatory Activities of Diclofenac Sodium, Prednisolone and Atorvastatin in Combination with Ascorbic Acid

2020 ◽  
Vol 19 (3) ◽  
pp. 291-301 ◽  
Author(s):  
Tanvir Ahmed ◽  
Sabrina Rahman Archie ◽  
Asef Faruk ◽  
Fabliha Ahmed Chowdhury ◽  
Abdullah Al Shoyaib ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Defense Mechanism ◽  
Diclofenac Sodium ◽  
Antiinflammatory Drugs ◽  
Inflammatory Drugs ◽  
Anti Inflammatory ◽  
Inflammation Group ◽  
Neuropsychiatric Effect ◽  
Normal Defense

Objectives: Inflammation is our body’s normal defense mechanism, but in some cases, it may be responsible for causing different kinds of disorders. Several antiinflammatory drugs are present for the treatment of these disorders; however, the conventional anti-inflammatory drugs cause side effects when used in the long term and therefore, it is better to use them in a low dose for a shorter duration of time. This study was designed to find out whether there is an augmentation of the therapeutic effectiveness of the antiinflammatory drugs like diclofenac sodium (NSAID), prednisolone (steroid) and atorvastatin (statin) when used in combination with ascorbic acid (antioxidant). Methods: Wistar Rats (n=144) were selected and divided into 24 groups of 6 rats in each. Carrageenan and formalin were used to induce local inflammation and neuropsychiatric effects, respectively. The inhibitions of such responses were measured after administering a drug alone and in combination with ascorbic acid. Results: In case of carrageenan mediated inflammation, the combination of 5 mg/kg diclofenac and 200 mg/kg ascorbic acid gave the highest inhibition of 74.19% compared to other groups of drugs. The combination of 5 mg/kg diclofenac and 200 mg/kg ascorbic acid gave 97.25% inhibition for formalin-mediated inflammation group. In both cases, combination therapy showed statistically significant anti-inflammatory activities compared to monotherapy (p values <0.05). Conclusion: All the data clearly indicate new combinations of drug therapy comprising diclofenac sodium, prednisolone, atorvastatin with ascorbic acid, which may be more effective against both local edema and the neuropsychiatric effect caused due to inflammation.

scholarly journals Associations of streptococci and fungi amounts in the oral cavity with nutritional and oral health status in institutionalized elders: a cross sectional study

2021 ◽  
Author(s):  
Hanako Sato ◽  
Akira Yano ◽  
Yu Shimoyama ◽  
Toshiro Sato ◽  
Yukiko Sugiyama ◽  
...  
Keyword(s):  
Health Status ◽  
Oral Health ◽  
Oral Cavity ◽  
Oral Health Status ◽  
Health Condition ◽  
Significant Variable ◽  
Oral Streptococci ◽  
Older Individuals ◽  
Oral Flora ◽  
Indigenous Bacteria

Abstract Background:Disruption of the indigenous microflora is likely to relate with frailty caused by undernutrition. However, relationship between undernutrition and oral flora, especially normal indigenous bacteria, is not obvious. The aim of this study was to elucidate the associations of nutritional and oral health conditions with bacteria and fungi prevalence in oral cavity of older individuals.Methods:Forty-one institutionalized older individuals with an average age ± standard deviation of 84.6 ± 8.3 years were enrolled in this study. Body mass index (BMI) and Oral health assessment tool (OHAT) were used to represent nutritional and oral health status. Amounts of total bacteria, streptococci, and fungi in oral specimens collected from the tongue dorsum were determined by quantitative polymerase chain reaction (PCR) assay results. Results:There found a significant correlation between BMI and streptococcal amount (ρ=0.526, p<0.001). In addition, the undernutrition group (BMI <20) showed a significantly lower average number of oral streptococci (p=0.003). In logistic regression models, streptococcal amount was the significant variable accounting for “not undernutrition” [odds ratio 5.68 and 95% confidential interval (CI) was 1.64-19.7 (p=0.06)]. On the other hand, participants with poor oral health condition (OHAT ≥5) harbored significantly higher level of fungi (p=0.028). Conclusion:Oral streptococci were associated with systemic nutritional condition and oral fungi were associated with oral health condition. Thus, it is necessary to examine oral indigenous bacteria as well as etiological microorganisms in order to understand the relationship of frailty with oral microflora in older individuals.

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