The distribution of the cariogenic bacterium Streptococcus mutans in the gastrointestinal tract of monkeys (Macaca fascicularis)

1982 ◽  
Vol 27 (8) ◽  
pp. 697-700 ◽  
Author(s):  
J. Walker ◽  
H. Hayday ◽  
D. Beighton
Keyword(s):  
Gastrointestinal Tract ◽  
Streptococcus Mutans ◽  
Macaca Fascicularis ◽  
Cariogenic Bacterium

scholarly journals dprandsodin Streptococcus mutans Are Involved in Coexistence with S. sanguinis, and PerR Is Associated with Resistance to H2O2

2012 ◽  
Vol 79 (5) ◽  
pp. 1436-1443 ◽  
Author(s):  
Kei Fujishima ◽  
Miki Kawada-Matsuo ◽  
Yuichi Oogai ◽  
Masayuki Tokuda ◽  
Mitsuo Torii ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Streptococcus Mutans ◽  
Dental Plaque ◽  
Stress Factors ◽  
Wild Type ◽  
Content Type ◽  
Stress Genes ◽  
Large Numbers ◽  
Cariogenic Bacterium ◽  
Population Ratio

ABSTRACTLarge numbers of bacteria coexist in the oral cavity.Streptococcus sanguinis, one of the major bacteria in dental plaque, produces hydrogen peroxide (H2O2), which interferes with the growth of other bacteria.Streptococcus mutans, a cariogenic bacterium, can coexist withS. sanguinisin dental plaque, but to do so, it needs a means of detoxifying the H2O2produced byS. sanguinis. In this study, we investigated the association of three oxidative stress factors, Dpr, superoxide dismutase (SOD), and AhpCF, with the resistance ofS. sanguinisto H2O2. The knockout ofdprandsodsignificantly increased susceptibility to H2O2, while the knockout ofahpCFhad no apparent effect on susceptibility. In particular,dprinactivation resulted in hypersensitivity to H2O2. Next, we sought to identify the factor(s) involved in the regulation of these oxidative stress genes and found that PerR negatively regulateddprexpression. The knockout ofperRcaused increaseddprexpression levels, resulting in low-level susceptibility to H2O2compared with the wild type. Furthermore, we evaluated the roles ofperR,dpr, andsodwhenS. mutanswas cocultured withS. sanguinis. Culturing of thedprorsodmutant withS. sanguinisshowed a significant decrease in theS. mutanspopulation ratio compared with the wild type, while theperRmutant increased the ratio. Our results suggest thatdprandsodinS. mutansare involved in coexistence withS. sanguinis, and PerR is associated with resistance to H2O2in regulating the expression of Dpr.

Effect of Bisphenol A Glycol Methacrylate on Virulent Properties of Streptococcus mutans UA159

2018 ◽  
Vol 53 (1) ◽  
pp. 84-95 ◽  
Author(s):  
Kyungsun Kim ◽  
Jung-Sub An ◽  
Bum-Soon Lim ◽  
Sug-Joon Ahn
Keyword(s):  
Bisphenol A ◽  
Streptococcus Mutans ◽  
Early Stage ◽  
Sugar Transport ◽  
Mechanical Degradation ◽  
Planktonic Growth ◽  
Oral Environment ◽  
Glucan Synthesis ◽  
Cariogenic Bacterium ◽  
Biofilm Development

Bisphenol A glycidyl methacrylate (bis-GMA), which is released into the oral environment by dental composites through incomplete polymerization, hydrolysis, and mechanical degradation, can significantly influence oral ecology around resin-based materials. The purpose of this study was to investigate how bis-GMA changes the virulence properties of Streptococcus mutans, a major cariogenic bacterium in humans. The results show that bis-GMA not only inhibited the planktonic growth of cells in medium containing glucose, fructose, or mannose, but also reduced the viability of S. mutans. However, the presence of bis-GMA increased sugar transport and intracellular polysaccharide accumulation in S. mutans, thereby increasing the potential of cell persistence. In addition, bis-GMA could enhance S. mutans’s adhesion to hard surfaces and glucan synthesis, which could contribute to biofilm formation. Although free bis-GMA made cells vulnerable to acidic stress, it also provided increased resistance to hydrogen peroxide, which might confer an advantage in competition with other oral microorganisms during the early stage of biofilm development. Interestingly, the presence of bis-GMA did not change the ability of S. mutans to interact with saliva. The results suggest that leachable bis-GMA could contribute to biofilm-related secondary dental caries at the marginal interface between resin-based materials and teeth by altering the virulent properties of S. mutans, although bis-GMA reduced the planktonic growth and viability of S. mutans.

Preclinical Trial of the Effectiveness of the Safety Nasogastric Tube to Detecting Tube Position Based on Tidal Volume and Pepsin Assay Results in the Gastrointestinal Tract of Macaca Fascicularis

2021 ◽  
Author(s):  
Neng Tine Kartinah ◽  
Sigit Mohammad Nuzul ◽  
Busjra M. Nur ◽  
Ermita Isfandiary Ibrahim
Keyword(s):  
Gastrointestinal Tract ◽  
Respiratory Tract ◽  
Tidal Volume ◽  
Nasogastric Tube ◽  
Macaca Fascicularis ◽  
Preclinical Trial ◽  
High Effectiveness ◽  
Imaging Guidance ◽  
Significant Difference ◽  
Tube Position

Abstract Background: Generally, insertion of a nasogastric tube (NGT) does not use imaging guidance. This procedure has a risk of malposition to the lungs from 0.3–15%. The NGT verification only detects the position of the tube in the end of procedure. Misplacement of NGT into the respiratory tract can result in damage to the lungs. Safety nasogastric tube (SNGT) has been created to detect the position of the tube in real-time, simple, and inexpensive. This study aims to prove the effectiveness of the SNGT prototype in Macaca fascicularis. Result: The SNGT with an airbag size of 50% of tidal volume (SNGT 50% TV) had 100% sensitivity and specificity in detecting the position of the tube. While the SNGT with an airbag size of 100% of TV (SNGT 100% TV) has sensitivity of 100% and specificity of 87.5%. There was significant difference between the movement of airbag of SNGT 50% TV and SNGT 100% TV (p ≤ 0.05). However, there was no significant difference between the accuracy of placement of 50% TV SNGT, 100% TV SNGT, and conventional NGT (p > 0.05). The pepsin enzyme has better sensitivity (100%) than pH paper (91.66%) in detecting the end position of tube. Conclusion: SNGT tube has high effectiveness in detecting the position of the tube inside of the respiratory and digestive tracts to prevent misplacement.

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