Group A Streptococcus translocates across an epithelial barrier via degradation of intercellular junctions
Conclusion Our investigations of interactions of bacteria with intercellular junctions have provided further insight into the mechanisms used by GAS to disrupt the epithelial barrier. Elucidation of molecular mechanisms underlying the initial stage of GAS infections in these studies may expedite development of novel preventive or therapeutic agents for severe invasive GAS infections. (Source: Journal of Oral Biosciences)
Source: Journal of Oral Biosciences - May 12, 2015 Category: Biomedical Science Source Type: research
Purification and characterization of hemolysin from Prevotella oris
Publication date: May 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 2 Author(s): Toshiya Sato , Arihide Kamaguchi , Futoshi Nakazawa We observed hemolytic activity in culture supernatant of Prevotella oris. Results from growth-phase experiments show that hemolysin production increased during the logarithmic growth phase and decreased during the stationary phase. The hemolysin produced by P. oris was purified from the culture supernatant by ultrafiltration, diethylaminoethyl (DEAE) and carboxymethyl (CM) ion-exchange chromatography, and gel filtration chromatography; further, we investigated the purified ...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Microbial composition of dental plaque microflora on first molars with orthodontic bands and brackets, and the acidogenic potential of these bacteria
Discussion and conclusion These results indicate that there are differences in the microbial composition and acidogenic potential of supragingival plaque from first molars with bands, brackets, or without appliances, and suggest that supragingival plaque on teeth with brackets carries predominantly periodontitis-associated bacteria but less caries-associated bacteria. (Source: Journal of Oral Biosciences)
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Applications of functional magnetic resonance imaging for analysis of oral functions
Publication date: May 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 2 Author(s): Yoshinori Sahara , Takuya Kobayashi , Haruka Toya , Tetsuya Suzuki Functional magnetic resonance imaging (fMRI) has considerably advanced the understanding of peripheral and central neural mechanisms underlying orofacial movements (e.g., chewing, swallowing, digestion, and speech). The principle advantages of fMRI lie in its noninvasive nature, relatively high spatiotemporal resolution, and ability to identify the entire network of brain areas involved in particular tasks. However, there remain substantial and valid critici...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
The virulence factors and pathogenic mechanisms of Streptococcus pyogenes
Publication date: May 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 2 Author(s): Yutaka Terao Streptococcus pyogenes possesses a wide variety of virulence factors and can cause severe invasive infections. Most S. pyogenes express surface-located fibronectin-binding proteins as major invasion molecules. We identified 2 novel fibronectin-binding proteins (FbaA and FbaB) in S. pyogenes isolated from patients with severe invasive infection. Fba-deficient mutant strains showed significantly lower efficiency of invasion of human epithelial cells than that shown by an isogenic wild type strain. Furthermore, comp...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Current status of tuberculosis and recombinant bacillus Calmette-Guérin vaccines
Publication date: May 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 2 Author(s): Naoya Ohara Tuberculosis (TB) is an infectious disease and a global concern of enormous proportions. One-third of the world's population is latently infected with Mycobacterium tuberculosis, and 2 million people die from TB annually. The only currently available vaccine—bacillus Calmette-Guerin (BCG)—is the most extensively used vaccine ever, with a record 3 billion doses administered during the last 4 decades. Because BCG is a live attenuated vaccine, it can be developed by genetic engineering to serve as a foreign antige...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Factors affecting susceptibility of Staphylococcus aureus to antibacterial agents
Publication date: May 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 2 Author(s): Miki Kawada-Matsuo , Hitoshi Komatsuzawa Staphylococcus aureus is a major human pathogen that causes suppurative diseases, toxic shock syndrome, pneumonia, food poisoning, and staphylococcal scalded skin syndrome (SSSS). S. aureus can also cause osteomyelitis and radicular cysts that impact dental health. β-lactam antibiotics are frequently used for the treatment of S. aureus infections, but the emergence of methicillin-resistant S. aureus (MRSA) has caused serious problems for the antibiotic treatment of S. aureus infectio...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
SNARE mediates autophagosome–lysosome fusion
Publication date: May 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 2 Author(s): Nobumichi Furuta , Atsuo Amano Autophagy is an intracellular bulk degradation/recycling system that turns over cellular constituents. This system has also been shown to play a crucial role in host defense, termed antimicrobial autophagy (xenophagy), in which it functions to degrade intracellular foreign microbial invaders. Xenophagosomes undergo a stepwise maturation process that consists of fusion with lysosomes, after which the cargo undergoes degradation. We have previously shown that intracellular group A Streptococcus (G...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Irsogladine maleate regulates barrier function and neutrophil accumulation in the gingival epithelium
Publication date: May 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 2 Author(s): Tsuyoshi Fujita , Hideki Shiba , Hidemi Kurihara Epithelial cells function as mechanical barriers against invasion by pathogenic organisms and promote intercellular communication through cell–cell junction complexes. Therefore, the permeability of the gingival epithelial cell layer indicates a defensive capability against invasion by periodontal pathogens. Accumulation of activated neutrophils is thought to be involved in the onset of inflammation. Here, we review the effects of irsogladine maleate, a medication for gastri...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Role of Smad phosphatases in BMP-Smad signaling axis-induced osteoblast differentiation
In conclusion, SCP1 and PPM1A suppress the osteoblast differentiation induced by BMPs independent of Smad dephosphorylation. (Source: Journal of Oral Biosciences)
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Hormones and bioactive substances that affect peripheral taste sensitivity
Publication date: May 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 2 Author(s): Ryusuke Yoshida Taste receptor cells in taste buds detect chemical compounds in foods and drinks and transmit these signals through gustatory nerve fibers to the central nervous system. Sensory signals of taste are essential for animal feeding behavior; animals prefer sweet taste and avoid bitter and sour tastes. Recent studies have demonstrated that the sensitivity of taste receptor cells to tastants is not constant but is subject to regulation by hormones and bioactive substances, such as leptin and endocannabinoids. Leptin ...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Microbial interaction of periodontopathic bacteria and Epstein-Barr virus and their implication of periodontal diseases
Publication date: August 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 3 Author(s): Kenichi Imai , Yorimasa Ogata , Kuniyasu Ochiai Epstein-Barr virus (EBV) is a ubiquitous human gamma herpesvirus that infects more than 90% of the world's population. EBV infection causes several human diseases, including infectious mononucleosis, autoimmune disorders, and a number of malignancies. Interestingly, evidence accumulated over the past 10 years supports the role for EBV as a pathogenic agent of periodontal disease because bacterial activities alone do not explain several of its clinical characteristics. Despit...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Porphyromonas gingivalis FimA fimbriae: Roles of the fim gene cluster in the fimbrial assembly and antigenic heterogeneity among fimA genotypes
Publication date: August 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 3 Author(s): Keiji Nagano , Yuki Abiko , Yasuo Yoshida , Fuminobu Yoshimura In order for bacteria to exert their pathogenicity, they must adhere to and colonize the host tissues. Porphyromonas gingivalis, a periodontal pathogen, primarily exploits FimA fimbriae for adhesion and colonization. FimA fimbriae are polymers composed of FimA protein encoded by the fimA gene. The fimA gene exists as a single copy within the fim gene cluster. This fim gene cluster contains 7 genes: fimX, pgmA, and fimABCDE. In this article, we address the rol...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Strategies for targeting the gingipain secretion system of Porphyromonas gingivalis
Publication date: August 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 3 Author(s): Keitarou Saiki , Kiyoshi Konishi Porphyromonas gingivalis is considered the most important etiologic agent in chronic periodontitis. P. gingivalis secretes several proteases that promote disease progression by degrading host cells and proteins. P. gingivalis is asaccharolytic and uses peptides as an energy source; therefore, peptide fragments arising from the digestion of host proteins are important for multiplication of this bacterium. Gingipains are secretory endoproteases of P. gingivalis with trypsin-like activity and...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
Nuclear dot protein 52, an autophagy-associated protein, regulates Toll-like receptor signaling
Publication date: August 2012 Source:Journal of Oral Biosciences, Volume 54, Issue 3 Author(s): Megumi Inomata , Takeshi Into Toll-like receptors (TLRs) recognize molecular patterns on various microbes and serve as innate immune sensors. After cognate ligand recognition, TLRs activate signaling pathways to induce innate immune defense mechanisms, which eliminate pathogenic microbes, including periodontogenic bacteria, to a certain extent. Recent findings have shown that TLR signaling is linked to induction of autophagy to facilitate direct killing of cytosol-invading bacteria within infected cells. However, whether a...
Source: Journal of Oral Biosciences - April 24, 2015 Category: Biomedical Science Source Type: research
