22 research outputs found
Tooth whitening with hydrogen peroxide in adolescents: study protocol for a randomized controlled trial
Effectiveness of carbamide peroxide and sodium perborate in non-vital discolored teeth
Effects on gastric mucosa induced by dental bleaching – an experimental study with 6% hydrogen peroxide in rats
KOMPOZİT REZİNLERİN POLİMERİZASYONLARI ESNASINDA PULPA ODASINDAKİ ISI DEĞİŞİMLERİNİN İN VİTRO DEĞEİRLENDİRİLMESİ
Bu in vitro çal›şman›n amac›, kompozit rezin polimerizasyonu esnas›nda pulpa odas›nda oluşabilecek ›s› değişikliklerini değerlendirmektir. 40 adet çekilmiş maxiller santral insan dişi kullan›ld›. Dişlerin vestibul yüzeylerine 5 mm çap›nda, 2 mm yüksekliğinde standart kaviteler aç›ld›, dişler rasgele 4 gruba ayr›ld›. Dişlerin kökleri mine-sement birleşiminden yaklaş›k olarak 4 mm aşağ›da olacak şekilde kesildi, pulpa dokusu headström eğeler ile uzaklaşt›r›ld›. Her dişin pulpa odas›na digital termometrenin termocouple’› yerleştirildi ve radyografi ile kontrol edildi. Daha sonra bir ak›şkan Tetric-Flow , bir kondanse edilebilir Surefil ,bir hybrid Charisma ve bir ormoser esasl› Admira kompozit rezinler kavitelere yerleştirilerek 40 s ›ş›k cihaz› ile polimerize edildiler. Polimerizasyon esnas›ndaki ›s› art›şlar› kaydedildi. Sonuçlar istatistiksel olarak Varyans Analizi ve Duncan testi ile değerlendirildi. En yüksek ›s› art›ş› ak›şkan kompozit grubunda gözlendi. Diğer kompozit rezinler aras›nda istatistiksel olarak önemli farkl›l›k bulunmad›.
An efficient approach for the isolation, identification and evaluation of antimicrobial plant components on an analytical scale, demonstrated by the example of Radix imperatoriae
Using Radix imperatoriae (the root of masterwort) as an example, we describe an efficient approach for the isolation, identification and evaluation of bioactive plant components on an analytical scale. The extraction of Radix imperatoriae with ethyl acetate was enhanced by the application of ultrasound oscillations. This rhizome extract was applied to three pathogenic bacteria ( Bacillus cereus, Escherichia coli, and Staphylococcus aureus) to determine its antimicrobial activity. Disk diffusion was utilized to determine susceptibility. The extract components were separated using a series of chromatography approaches (semi-preparative RP-HPLC, or RP-HPLC on an analytical scale), followed by testing. All fractions were analyzed by LC-UV-ESI-MS and 600 MHz microcoil H NMR spectroscopy. Among other findings, in the fraction with the highest antibacterial activity we were able to identify oxypeucedanin and oxypeucedanin hydrate. Subsequent analysis revealed that only oxypeucedanin hydrate had antibacterial activity, whereas oxypeucedanin itself was inactive at the concentrations applied. Furthermore, oxypeucedanin hydrate appears to be largely, or exclusively, a by-product of sample preparation, since it is either not synthesized by the plant as a second metabolite or is produced by it in only very small quantities
An efficient approach for the isolation, identification and evaluation of antimicrobial plant components on an analytical scale, demonstrated by the example of Radix imperatoriae
Using Radix imperatoriae (the root of masterwort) as an example, we describe an efficient approach for the isolation, identification and evaluation of bioactive plant components on an analytical scale. The extraction of Radix imperatoriae with ethyl acetate was enhanced by the application of ultrasound oscillations. This rhizome extract was applied to three pathogenic bacteria ( Bacillus cereus, Escherichia coli, and Staphylococcus aureus) to determine its antimicrobial activity. Disk diffusion was utilized to determine susceptibility. The extract components were separated using a series of chromatography approaches (semi-preparative RP-HPLC, or RP-HPLC on an analytical scale), followed by testing. All fractions were analyzed by LC-UV-ESI-MS and 600 MHz microcoil H NMR spectroscopy. Among other findings, in the fraction with the highest antibacterial activity we were able to identify oxypeucedanin and oxypeucedanin hydrate. Subsequent analysis revealed that only oxypeucedanin hydrate had antibacterial activity, whereas oxypeucedanin itself was inactive at the concentrations applied. Furthermore, oxypeucedanin hydrate appears to be largely, or exclusively, a by-product of sample preparation, since it is either not synthesized by the plant as a second metabolite or is produced by it in only very small quantities
Anal Bioanal Chem DOI 10.1007/s00216-010-4153-2 ORIGINAL PAPER
efficient approach for the isolation, identification and evaluation of antimicrobial plant components on an analytical scale, demonstrated by the example of Radix imperatoria