Development of tissue conditioner capable of binding with anti-microbial protein lactoferrin.

PURPOSE: This study focused on the anti-microbial protein human lactoferrin (hLF) commonly found in saliva, and tried to develop biocompatible dental materials that have higher anti-microbial effects. METHODS: A lyophilized cation exchange resin was added to tissue conditioner at 4 wt% and 8 wt%. The amount of hLF binding to the tissue conditioner and their anti-microbial effect against Candida albicans was investigated. Then their mechanical properties and cytotoxicity were examined. RESULTS: Tissue conditioner containing cation exchange resin was bound with hLF and had an anti-microbial effect against C. albicans. In addition, their physical properties were sufficient and they were harmless to human fibroblasts. CONCLUSION: The clinical application of cation exchange resin for tissue conditioner can be effective for the prevention and treatment of denture stomatitis and systemic opportunistic infections since it is thought that these materials will increase the local concentration of anti-microbial protein in saliva at the lesion site.

[Planning guidelines for prosthodontic treatment].

In recent years "practice guidelines" based on EBM techniques have even been attracting attention at a societal level, and guidelines modeled after the procedure for preparing practice guideline (described at http://www.niph.go.jp/glgl-4.3rev.htm) have begun to be drafted and made public. With the aim of ensuring the quality and presenting the basic concepts of prosthodontic therapy, the Japan Prosthodontic Society, which bears a great obligation and responsibility toward society and the Japanese public, has decided to undertake the formulation of guidelines related to prosthodontic therapy, and decided to first undertake the formulation of "Practice guideline for denture relining and rebasing", and to prepare a guideline model. We tried to prepare the guidelines according to the "Procedure for preparing practice guidelines", but because of the scientific uniqueness of prosthodontic treatment and dentistry, research to elucidate the basis of treatment has been insufficient, and we ultimately reconfirmed the current state of affairs in which it is difficult to perform. We therefore prepared the guidelines based on the limited evidence obtained in a search of the scientific literature and on the consensus of experts. The Japan Prosthodontic Society has investigated and prepared a Society guideline "model" to the extent possible at the present time, and it has prepared "Guidelines for adhesion bridge" and "Practice guidelines for denture prosthodontics" based on it. Nevertheless, the fact of the matter is that we are faced with numerous problems, and we think that in the future new bases and clinical knowledge will be accumulated by promoting scientific clinical research, and that the guidelines should be revised regularly based on them.

Biophysical analyses of the transthyretin variants, Tyr114His and Tyr116Ser, associated with familial amyloidotic polyneuropathy.

The familial amyloidotic polyneuropathy is strictly associated with point mutations in the coding region of the transthyretin gene. Here, we focused on the mutations in the monomer-monomer and dimer-dimer interaction site of the transthyretin tetramer. The naturally occurring amyloidogenic Tyr114His (Y114H) and Tyr116Ser (Y116S) variants formed more amyloid fibrils than the wild-type transthyretin, nonamyloidogenic Tyr116Val (Y116V) variant, and other amyloidogenic variants in previous studies. The secondary, tertiary, and quaternary structural stabilities of the Y114H and Y116S variants were compared with those of the wild-type transthyretin and nonamyloidogenic Y116V variant. The unfolding data indicated that the amyloidogenic Y114H and Y116S mutations reduced the stability of the secondary, tertiary, and quaternary structure. Our results also indicated that the unfolding of Y114H and Y116S is less cooperative than that of the wild-type transthyretin. Moreover, the tetramer of the amyloidogenic variants dissociated to the monomer even at pH 7.0, indicating the importance of Tyr114 and Tyr116 in strengthening the contacts between monomers and/or dimers of the transthyretin molecule.