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To exclusively evaluate, in vitro, the efficacy of five intracanal medicaments against Candida albicans and Enterococcus faecalis in infected single-rooted primary teeth. Forty-three teeth were selected, out of which 42 were simultaneously contaminated with C. albicans and E. faecalis, verified by measuring the initial quantification (IQ), whereas one tooth was used as sterile control. Forty-two teeth were then randomly assigned to six groups (n = 7 teeth in each); one was the control group, while the others received calcium hydroxide (CH), camphorated paramonochlorophenol (CMCP), CH/CMCP, chlorhexidine (CHX), or iodoform paste (IP). Two samples from each group were then randomly selected and evaluated under a scanning electron microscope along with the sterile control (n = 1) for qualitative analyses (n = 13). The remaining samples (n = 30) were collected after 7 days of intracanal medicaments (final quantification - FQ) and 7 days after medicament removal (residual quantification - RQ). ANOVA and Tukey's and c2 tests (p £ 0.05) were performed for the statistical analysis. All the medicaments, except CMCP, significantly reduced the levels of C. albicans from IQ to FQ (p = 0.046). O nly CHX (p = 0.000) and IP (p = 0.007) showed a significant reduction from IQ to FQ against E. faecalis. The 2% CHX and IP demonstrated a favorable performance as an intracanal medicament, with a good antimicrobial activity against C. albicans and E. faecalis. [ABSTRACT FROM AUTHOR]

We evaluated the effects of dentine biomodification after pre-treatment with two sulphonamide carbonic anhydrase inhibitors (CAIs) of the N-[4-sulphamoylphenethylcarbamoyl]benzenesulphonamide type, investigating matrix metalloproteases activity, resin–dentine micro tensile bond strength, dentine surface wettability, and antimicrobial activities. Ninety-five sound-extracted human molars were selected for the study. Inhibitory effects were evaluated by gelatinase and collagenase activity tests and collagen degradation FT-IR spectroscopic analysis. Pre-treatment with the two CAIs kept the micro tensile values after 12 months of storage (32.23 ± 5.95) and cariogenic challenge (34.13 ± 2.71) similar to the initial, pre-treatment values (33.56 ± 4.34). A decreased Streptococcus mutans biofilm formation on dentine surfaces and antibacterial activity against planktonic bacteria were observed after CAI treatment. Dentine pre-treatment with sulphonamide CAIs maintained adhesion strength stability, allowed better dentine wettability, maintained matrix collagen, and showed anti-S. mutans activity. [ABSTRACT FROM AUTHOR]

Overexpression of the Saccharomyces cerevisiae ABC transporter Pdr5p confers resistance to a range of structurally unrelated xenobiotics. This property allows Pdr5p to be used as a target for novel multidrug resistance reversal reagents or chemosensitizers. Herein, we report the effects of gallic acid derivatives with substitutions either on the ester moiety or in the benzene ring on the activity of Pdr5p. Compounds with a longer side chain (8–16 carbons) resulted in greater inhibition of Pdr5p ATPase. Derivatives with side chains of 8–12 carbons that retained hydroxyl groups on the benzene ring extensively inhibited Pdr5p ATPase activity. These compounds almost completely inhibited the efflux of the Pdr5p fluorescent substrate Rhodamine 6G and at 25 μM chemosensitized the Pdr5p-overexpressing strain AD124567 to fluconazole (0.4 mg mL−1). Gallic acid derivatives may be a new class of Pdr5p inhibitors. [ABSTRACT FROM AUTHOR]

Examines the protection against thermal denaturation by trehalose on the plasma membrane H[sup +]-adenosine triphosphatase from yeast. Details on synergetic effects between sugar and lipids.

Baker's yeast cells accumulate osmolytes as a response to several stress conditions such as high temperature and low-temperature shifts, dehydration, or osmotic stress. One of the major osmolytes that accumulates is trehalose, which plays an essential role affecting the survival of yeast at the time of stress. In this report, we show that trehalose eflSciently protects the function and the structure of two yeast cytosolic enzymes against chemical denaturation by guanidinium chloride. Other sugars tested also protected yeast pyrophosphatase and glucose-6-phosphate dehydrogenase structure against guanidinium chloride effects, but were not as efficient at protecting enzyme activity. The thermostable pyrophosphatase from Bacillus stearothermophilus was also protected by several sugars against the chaotropic properties of guanidinium chloride, but was only protected by trehalose against functional inactivation. The function of the membrane-embedded H&plus−ATPase from yeast could not be protected by any of the tested sugars, although all of the sugars protected its structure from guanidinium-chloride-induced unfolding. The results presented in this study suggest that several sugars are able to prevent protein unfolding induced by a chaotropic compound. However, prevention of functional inactivation depends on the nature of the sugar. Trehalose was the most efficient, being able to protect many cytosolic enzymes against guanidinium chloride. The efficiency of protection also depended on the nature of the protein tested. This might explain why trehalose is one of the osmolytes accumulated in yeast and also why it is not the only osmolyte to accumulate. [ABSTRACT FROM AUTHOR]

To exclusively evaluate, in vitro, the efficacy of five intracanal medicaments against Candida albicans and Enterococcus faecalis in infected single-rooted primary teeth. Forty-three teeth were selected, out of which 42 were simultaneously contaminated with C. albicans and E. faecalis, verified by measuring the initial quantification (IQ), whereas one tooth was used as sterile control. Forty-two teeth were then randomly assigned to six groups (n = 7 teeth in each); one was the control group, while the others received calcium hydroxide (CH), camphorated paramonochlorophenol (CMCP), CH/CMCP, chlorhexidine (CHX), or iodoform paste (IP). Two samples from each group were then randomly selected and evaluated under a scanning electron microscope along with the sterile control (n = 1) for qualitative analyses (n = 13). The remaining samples (n = 30) were collected after 7 days of intracanal medicaments (final quantification - FQ) and 7 days after medicament removal (residual quantification - RQ). ANOVA and Tukey's and c2 tests (p £ 0.05) were performed for the statistical analysis. All the medicaments, except CMCP, significantly reduced the levels of C. albicans from IQ to FQ (p = 0.046). Only CHX (p = 0.000) and IP (p = 0.007) showed a significant reduction from IQ to FQ against E. faecalis. The 2% CHX and IP demonstrated a favorable performance as an intracanal medicament, with a good antimicrobial activity against C. albicans and E. faecalis.

Overexpression of the Saccharomyces cerevisiae ABC transporter Pdr5p confers resistance to a range of structurally unrelated xenobiotics. This property allows Pdr5p to be used as a target for novel multidrug resistance reversal reagents or chemosensitizers. Herein, we report the effects of gallic acid derivatives with substitutions either on the ester moiety or in the benzene ring on the activity of Pdr5p. Compounds with a longer side chain (8-16 carbons) resulted in greater inhibition of Pdr5p ATPase. Derivatives with side chains of 8-12 carbons that retained hydroxyl groups on the benzene ring extensively inhibited Pdr5p ATPase activity. These compounds almost completely inhibited the efflux of the Pdr5p fluorescent substrate Rhodamine 6G and at 25 muM chemosensitized the Pdr5p-overexpressing strain AD124567 to fluconazole (0.4 mg mL(-1)). Gallic acid derivatives may be a new class of Pdr5p inhibitors.