Inhibition of adherence of the yeast Candida albicans to buccal epithelial cells by synthetic aromatic glycoconjugates.

The yeast Candida albicans is an opportunistic fungal pathogen which induces superficial and systemic infections in immunocompromised patients. Adherence to host tissue is critical to its ability to colonise and infect the host. The work presented here describes the synthesis of a small library of aromatic glycoconjugates (AGCs) and their evaluation as inhibitors of C. albicans adherence to exfoliated buccal epithelial cells (BECs). We identified a divalent galactoside, ligand 2a, capable of displacing over 50% of yeast cells already attached to the BECs. Fluorescence imaging indicates that 2a may bind to structural components of the fungal cell wall.

Histological, histomorphometric, and radiographic evaluation of a sinus augmentation with a new bone allograft: a clinical case report.

PURPOSE: This case report documents the histological, histomorphometric, and radiographic effects of a new radiated-preserved bone allograft for sinus elevation procedures. MATERIALS AND METHODS: This unique bone substitute differs from other forms of bone allograft processed through the standard cryopreservation method. Histology from bone biopsy core samples revealed newly formed bone with a well-organized lamellar bone structure in general and remaining particles were observed in contact with surrounding newly-formed bone. RESULTS: Histomorphometric results demonstrated an average new bone formation of 31.8%. Radiographic linear data demonstrated an 8.49% +/- 6.77% graft resorption from baseline to 6 months. CONCLUSION: The outcome of this report suggests that this bone allograft could be successfully used in sinus lifting procedures. It encourages further research of this radiated-preserved bone allograft material in oral and maxillofacial reconstruction.

Subgingival microbiologic effects of one-time irradiation by CO2 laser: a pilot study.

BACKGROUND: Third-generation carbon dioxide (3-CO(2)) lasers have handpieces that accommodate a periodontal insert that permits irradiation directly into the periodontal pocket/sulcus. The purpose of this pilot study was to evaluate, by scanning electron microscopy (SEM), the surface effects of 3-CO(2) laser treatment on the root surfaces and soft tissues and to investigate the effects of 3-CO(2) laser on periodontal pathogenic bacteria compared to negative controls. METHODS: Five patients with chronic periodontitis and treatment planned for a maxillary immediate denture were included in the study. Periodontal pockets with a mean probing depth of 5.5 +/- 0.8 mm were irradiated one time by CO(2) laser (wavelength of 10,600 nm) at a power of 2.2 W, 50 Hz, an 80-millisecond pulse length, and an exposure rate of 1 mm per 5 seconds. DNA analysis of eight periodontal bacteria was performed on samples collected from laser-treated and control sites prior to and immediately following treatment and was compared between groups. In addition, block biopsies, including soft tissue, were harvested for SEM examination. RESULTS: SEM examination of test group specimens showed heat damage on the soft tissues in three of 17 specimens (17.6%). In addition, 11.7% (two of 17) of the 3-CO(2)-treated teeth exhibited localized slight damage to root surfaces. Microbiologic results of the control sites indicated that 90.6% of the bacterial counts remained the same, 6% increased, and 3% decreased. In the test group, 71.25% of the bacterial count analyses for the eight different periodontal microbes remained the same, 12.50% increased, and 16.25% decreased. CONCLUSION: A one-time use of the 3-CO(2) laser in periodontal pockets did not sterilize or substantially reduce subgingival bacterial populations compared to negative controls.

Reboxetine: attenuation of intravenous nicotine self-administration in rats.

The ability of reboxetine, a selective inhibitor of the norepinephrine transporter and noncompetitive antagonist at neuronal nicotinic receptors, to alter nicotine self-administration in rats was compared with that of mecamylamine, a classical noncompetitive antagonist at nicotinic receptors. The ability of reboxetine to alter sucrose-maintained responding was also examined to assess the specificity of the effect on nicotine self-administration. Rats were trained on a fixed ratio 5 schedule to self-administer nicotine (0.02 mg/kg/infusion i.v.) or to respond for sucrose pellets. Upon reaching a stable baseline, rats were pretreated 15 min before the session with vehicle, reboxetine (racemic), (+)-(S,S)-reboxetine (0.3-30 mg/kg s.c.) or mecamylamine (0.5-4 mg/kg s.c). To assess the effect of repeated administration, reboxetine (5.6 mg/kg) was injected once daily for 14 consecutive sessions before either nicotine self-administration or sucrose-maintained responding. Specificity was further assessed by examining the ability of repeated administration of reboxetine (5.6 mg/kg) to alter nicotine-induced hyperactivity (0.8 mg/kg). Reboxetine, (+)-(S,S)-reboxetine, and mecamylamine dose dependently decreased nicotine self-administration by ~60%, whereas reboxetine and (+)-(S,S)-reboxetine decreased sucrose-maintained responding to a lesser extent (~20%). Repeated administration of reboxetine (5.6 mg/kg) decreased nicotine self-administration and sucrose-maintained responding across the 14 sessions, suggesting that tolerance did not develop to these effects of reboxetine. Additionally, reboxetine did not alter baseline locomotor activity, indicating that the decrease in operant responding for nicotine and sucrose was not the result of a nonspecific decrease in activity. The reboxetine-induced decrease in nicotine self-administration and sucrose-maintained responding may be the result of inhibition of norepinephrine transporters and/or neuronal nicotinic receptor function.