최봉규 교수

Parkinson disease and dementia with Lewy bodies are featured with the formation of Lewy bodies composed mostly of α-synuclein (α-Syn) in the brain. Although evidence indicates that the large oligomeric or protofibril forms of α-Syn are neurotoxic agents, the detailed mechanisms of the toxic functions of the oligomers remain unclear. Here, we show that large α-Syn oligomers efficiently inhibit neuronal SNARE-mediated vesicle lipid mixing. Large α-Syn oligomers preferentially bind to the N-termina

To determine the genetic diversity of cultivable and uncultivable spirochetes in the gingival crevice of a patient with severe periodontitis, partial 16S rRNA genes were cloned from PCR-amplified products of DNA and RNA extracted from a subgingival plaque sample. Approximately 500 bp were amplified in PCRs by using universally conserved primers with polylinker tails. Purified PCR products were cloned into Escherichia coli by using the plasmid vector pUC19. The resultant clone library was screene

Digital dermatitis (DD), first described in 1974 by Cheli and Mortellaro (R. Cheli and C. Mortellaro, p. 208-213, in Proceedings of the 8th International Conference on Diseases of Cattle, 1974), is a major problem in diary cows and beef cattle causing significant economic losses worldwide. Lesions are typically found at the volar skin proximal to the heel bulbs. Microscopic examination of biopsies or touch preparations of these lesions revealed a variety of different bacterial morphotypes includ

Autoinducer 2 (AI-2) is a quorum sensing molecule to which bacteria respond to regulate various phenotypes, including virulence and biofilm formation. AI-2 plays an important role in the formation of a subgingival biofilm composed mostly of Gram-negative anaerobes, by which periodontitis is initiated. The aim of this study was to evaluate D-galactose as an inhibitor of AI-2 activity and thus of the biofilm formation of periodontopathogens. In a search for an AI-2 receptor of Fusobacterium nuclea

Periodontitis is an inflammatory disease induced by local infection in tooth-supporting tissue. Periodontitis is associated with systemic bone diseases, but little is known about the mechanism of the causal effect of periodontitis on systemic bone resorption. Bacteria-derived extracellular vesicles (EVs) act as natural carriers of virulence factors that are responsible for systemic inflammation. In this study, we investigated the role of EVs derived from Filifactor alocis, a Gram-positive, anaer

These findings suggest that the osteoclastogenesis by P. gingivalis, T. denticola, and T. socranskii is mediated by a RANKL-dependent pathway and that PGE(2) is a main factor in the pathway by the enhancing of RANKL expression and the depression of osteoprotegerin, a RANKL inhibitor.

Using highly sensitive methods relying on 16S ribosomal RNA-based oligonucleotide probes, we confirmed the strong association of 7 putative periodontopathogens with AP patients in a Korean population. With the exceptions of Fusobacterium sp. and B. forsythus, all the periodontopathogens were significantly more associated with the healthy sites of periodontitis subjects than in the healthy sites of periodontally healthy subjects.

Alveolar bone destruction is a characteristic feature of periodontitis. Treponema denticola is known to be involved in periodontitis. To elucidate the role of T. denticola in alveolar bone destruction in periodontitis, the effects of lipooligosaccharide (LOS) from T. denticola on osteoclast formation and on expression of osteoclast differentiation factor (ODF) and osteoprotegerin (OPG) mRNAs were examined in a coculture system by using mouse calvaria and bone marrow cells. In addition, the effec

Recently, Riviere et al. reported as yet uncultivable invasive oral spirochetes that cross-reacted with monoclonal antibodies (MAbs) specific for Treponema pallidum (G. R. Riviere, K. S. Elliot, D. F. Adams, L. G. Simonson, L. B. Forgas, A. M. Nilius, and S. A. Lukehart, J. Periodontol. 63:131-136, 1992; G. R. Riviere, M. A. Wagoner, S. A. Baker-Zander, K. S. Weisz, D. F. Adams, L. Simonson, and S. A. Lukehart, N. Engl. J. Med. 325:539-543, 1991; G. R. Riviere, K. S. Weisz, D. F. Adams, and D. D