Publication: Sodyum Fluorid, Kalay Fluorid ve ksilitolün streptococcus mutans intrasellüler polisakkarid sentezi üzerine etkisinin sitokimyasal ve kimyasal yöntemlerle tayin edilmesi
Abstract
Bu çalışmanın amaçları, değişik konsantrasyonlu sodyum fluorid (NaF) ile kalay fluoridin (SnF2) kariyojenik Streptococcus mutans suşlarının intrasellüler polisakkarid (İPS) sentezini ne şekilde etkilediğini saptamak, bir diğer antikariyojenik ajan olan ksilitolün (xylitol) fluoridin metabolik etkisini arttırıp arttırmadığı tespit etmek, bu ajanların streptokokal glikoliz üzerine etkilerini araştırmak ve streptokokal İPS'yi elektron mikroskobu ile görüntülemektir. Öncelikle, klinikten izole edilen S. mutans GE1 ile tip suş olan S mutans NCTC 10449'un İPS sentezi yapabilme yeteneği test edildi. Bunun için mikroorganizmalar, Jordan's besiyerinde anaerobik olarak 24 saat 37°C'de inkübe edildi. Daha sonra bakteri kolonileri %2'lik iyot/ %0,2'lik potasyum iyodür solüsyonu ile boyandı. Kolonileri koyu kahve-siyah renkte boyanan streptokoklar İPS sentez edebilen streptokoklar, açık kahve veya sarı renkte boyanan streptokoklar ise İPS sentez edemeyen streptokoklar olarak değerlendirildi. Her iki S. mutans suşunun da İPS sentezi yaptığı saptandı. Ayrıca, bu mikroorganizmaların İPS sentezi nicel olarak kimyasal metodla da tayin edildi. Sodyum fluorid, kalay fluorid ve ksilitolün İPS üzerine etkilerini saptamak için bakteriler anaerobik olarak Todd-Hewitt buyyonda 24 saat 37°C'de farklı konsantrasyonlardaki test maddeleri ile üretildi. Test maddelerinin konsantrasyonları NaF için (ppm): 0, 5, 15, 30; SnF2 için (ppm): 0, 5, 15, 30; ksilitol için (ppm): 0, 100, 500 ve 1500; Fluorid ve ksilitol için: 0 ppm fluorid ve 0 ppm ksilitol, 30 ppm fluorid ve 100 ppm ksilitol; 70 ppm fluorid ve 100 ppm ksilitol olarak saptandı. Kullanılan tüm test maddeleri ile S. mutans İPS sentezinde istatistiksel olarak anlamlı oranda azalma tespit edilmiştir (P<0,05). Sodyum fluorid ve kalay fluorid İPS sentezi üzerine benzer etkiler göstermişlerdir. 5 ppm'lik konsantrasyonda uygulanan NaF ve SnF2 streptokok suşlarının intrasellüler polisakkarid sentezini %90'nın üzerinde azaltmıştır. Fluorid dozu 5 ppm'den 30 ppm'e çıkarıldığı zaman İPS'deki azalma belirgin olmayacak şekilde artış göstermiştir. Ksilitol her iki S. mutans suşunda da İPS sentezini inhibe etmiştir fakat fluoridin inhibisyon etkisini arttırmamıştır. Buna karşılık fluorid ksilitolun inhibisyon etkisini istatistiksel olarak anlamlı oranda arttırmıştır. İPS sentezi standart suş olan S. mutans NCTC 10449'un 70 ppm SnF2 ve 100 ppm ksilitollü Todd-Hewitt buyyonda üreyen hücrelerinde %93,14 oranında, klinik suş olan S. mutans GE1 hücrelerinde ise %94,62 oranında azalmıştır. Mann-Whitney U testi, sodyum fluorid ve sodyum fluorid/ ksilitol arasında ya da kalay fluorid ve kalay fluorid/ ksilitol arasında İPS sentezinin azaltılması bakımından istatistiksel olarak anlamlı bir etkileşim meydana gelmediğini göstermiştir. Streptokok suşlarının glikolitik aktivitesi glikoz veya glikoz ile birlikte çeşitli konsantrasyon ve kombinasyonda kullanılan farklı test maddeleri ile değerlendirilmiştir. Elde edilen sonuçlar S. mutans suşlarının asit üretiminin kullanılan konsantrasyonlardaki test maddelerinden etkilenmediğini göstermiştir. TEM'de, S. mutans hücrelerinin İPS'yi elektron yoğun granüller halinde depoladıkları tespit edildi. Granüllerin miktarca azalması, test maddelerinin İPS sentezini etkilediğini göstermiştir.
Tez Başlığı: CYTOCHEMICAL AND CHEMICAL DETERMINATION OF THE EFFECT OF SODIUM FLUORIDE, STANNOUS FLUORIDE, AND XYLITOL ON INTRACELLULER POLYSACCHARIDE SYNTHESIS IN STREPTOCOCCUS MUTANS SUMMARY: The aims of this study were, to determine the effect of various concentrations of sodium floride and stannous fluoride on the production of intracelluler polysaccharide (IPS) of two cariogenic strains of Streptococcus mutans, to determine whether xylitol inhibited accumulation of IPS or enhanced the anti-metabolic activity of fluoride, to examine the effects of these agents on streptococcal glycolysis, and to demonstrate the presence of streptococcal IPS through electron microscopic cytochemistry. Firstly, the strains of S. mutans, S. mutans GE1 and S. mutans NCTC 10449, were tested for their ability to produce intracellular polisaccharide. The Streptococcus strains were inoculated to Jordan's agar plates which were incubated at 37°C under anaerobic conditions for 24 hours. The bacterial colonies were then stained with 2% iodine in 0.2% potassium iodine solution. Colonies whose colors changed to dark brown-black were designated as IPS producing streptococci, and the other colonies, whose color was light brown-yellow were designated as non-IPS producing streptococci. It was determined that both strains of S. mutans were IPS producers. The IPS production by these organisms was also detected quantitatively with a chemical method. The effects of NaF, SnF2, and xylitol were determined by allowing the bacteria to grow in a Todd-Hewitt medium supplemented with different concentrations of test materials. The final concentrations of test materials were: NaF (ppm): 0, 5, 15, 30; SnF2 (ppm): 0, 5, 15, 30; xylitol (ppm): 0, 100, 500, 1500; fluorid and xylitol: 0 ppm fluoride and 0 ppm xylitol, 30 ppm fluoride and 100 ppm xylitol, 70 ppm fluoride and 100 ppm xylitol. It was found that the reduction of IPS by all the test materials was statistically significant (p<0.05). NaF and SnF2 inhibited IPS production in a similiar way. Fluoride in a concentration of 5 ppm consistently depressed the IPS accumulation by over 90%. There was little further reduction in IPS content when fluoride was increased from 5 to 30 ppm. Xylitol inhibited IPS synthesis in both strains of S. mutans but it didn't modify the inhibitory effects of fluoride. However, fluoride significantly enhanced the inhibitory effects of xylitol. The production of IPS in S. mutans NCTC 10449 was inhibited with the combination of 70 ppm SnF2 and 100 ppm xylitol by 93.14%. The inhibition in S. mutans GE1 was 94,62%. Mann-Whitney U indicated no statistically significant interaction between sodium fluoride and sodium fluoride/ xylitol, or stannous fluoride and stannous fluoride/ xylitol in terms of reducing IPS synthesis. The glycolitic activity of two strains of streptococci was determined with glucose or glucose with one of the test materials at different concentrations and combinations. The results showed that the rate of acid production of the S. mutans strains was not affected by the test materials at the concentrations tested. It was observed by TEM that the cells of S. mutans have stored IPS as distinct electron dense granules. The test materials effect on IPS was reflected by decrease in the number of these granules.
Tez Başlığı: CYTOCHEMICAL AND CHEMICAL DETERMINATION OF THE EFFECT OF SODIUM FLUORIDE, STANNOUS FLUORIDE, AND XYLITOL ON INTRACELLULER POLYSACCHARIDE SYNTHESIS IN STREPTOCOCCUS MUTANS SUMMARY: The aims of this study were, to determine the effect of various concentrations of sodium floride and stannous fluoride on the production of intracelluler polysaccharide (IPS) of two cariogenic strains of Streptococcus mutans, to determine whether xylitol inhibited accumulation of IPS or enhanced the anti-metabolic activity of fluoride, to examine the effects of these agents on streptococcal glycolysis, and to demonstrate the presence of streptococcal IPS through electron microscopic cytochemistry. Firstly, the strains of S. mutans, S. mutans GE1 and S. mutans NCTC 10449, were tested for their ability to produce intracellular polisaccharide. The Streptococcus strains were inoculated to Jordan's agar plates which were incubated at 37°C under anaerobic conditions for 24 hours. The bacterial colonies were then stained with 2% iodine in 0.2% potassium iodine solution. Colonies whose colors changed to dark brown-black were designated as IPS producing streptococci, and the other colonies, whose color was light brown-yellow were designated as non-IPS producing streptococci. It was determined that both strains of S. mutans were IPS producers. The IPS production by these organisms was also detected quantitatively with a chemical method. The effects of NaF, SnF2, and xylitol were determined by allowing the bacteria to grow in a Todd-Hewitt medium supplemented with different concentrations of test materials. The final concentrations of test materials were: NaF (ppm): 0, 5, 15, 30; SnF2 (ppm): 0, 5, 15, 30; xylitol (ppm): 0, 100, 500, 1500; fluorid and xylitol: 0 ppm fluoride and 0 ppm xylitol, 30 ppm fluoride and 100 ppm xylitol, 70 ppm fluoride and 100 ppm xylitol. It was found that the reduction of IPS by all the test materials was statistically significant (p<0.05). NaF and SnF2 inhibited IPS production in a similiar way. Fluoride in a concentration of 5 ppm consistently depressed the IPS accumulation by over 90%. There was little further reduction in IPS content when fluoride was increased from 5 to 30 ppm. Xylitol inhibited IPS synthesis in both strains of S. mutans but it didn't modify the inhibitory effects of fluoride. However, fluoride significantly enhanced the inhibitory effects of xylitol. The production of IPS in S. mutans NCTC 10449 was inhibited with the combination of 70 ppm SnF2 and 100 ppm xylitol by 93.14%. The inhibition in S. mutans GE1 was 94,62%. Mann-Whitney U indicated no statistically significant interaction between sodium fluoride and sodium fluoride/ xylitol, or stannous fluoride and stannous fluoride/ xylitol in terms of reducing IPS synthesis. The glycolitic activity of two strains of streptococci was determined with glucose or glucose with one of the test materials at different concentrations and combinations. The results showed that the rate of acid production of the S. mutans strains was not affected by the test materials at the concentrations tested. It was observed by TEM that the cells of S. mutans have stored IPS as distinct electron dense granules. The test materials effect on IPS was reflected by decrease in the number of these granules.