The analysis of oral microbial communities of wild-type and toll-like receptor 2-deficient mice using a 454 GS FLX Titanium pyrosequencer

Background: Although mice have long served as an animal model for periodontitis, information on the composition of their indigenous oral microbiota is limited. The aim of the current study was to characterize mouse oral bacterial flora by applying extensive parallel pyrosequencing using the latest model pyrosequencer, a Roche/454 Genome Sequencer FLX Titanium. In addition, the effect of Toll-like receptor (TLR) 2 deficiency on oral microbiota was evaluated. Results: Eight oral bacterial communities of wild-type (n = 4) and TLR2 knock-out (n = 4) C57BL/6 mice were characterized by analyzing 80,046 reads of 16S rRNA genes obtained by pyrosequencing. Excluding the PCR primers, the average length of each sequencing product was 443 bp. The average species richness of the murine oral bacterial communities was estimated to be about 200, but the communities were dominated by only two main phyla and several species. Therefore, the bacterial communities were relatively simple. The bacterial composition of the murine oral microbiota was significantly different from that of humans, and the lack of TLR2 had a negligible effect on the murine oral microbiota. Conclusion: Pyrosequencing using the Roche/454 FLX Titanium successfully characterized mouse oral bacterial communities. The relatively simple oral bacterial communities of mice were not affected by TLR2 deficiency. These findings will provide a basis for future studies on the role of periodontal pathogens in the murine model of periodontitis.This study was supported by grants R13-2008-008-01003-0 from the Korea Science and Engineering Foundation.

Atmospheric-Pressure Plasma Jet Induces Apoptosis Involving Mitochondria via Generation of Free Radicals

The plasma jet has been proposed as a novel therapeutic method for anticancer treatment. However, its biological effects and mechanism of action remain elusive. Here, we investigated its cell death effects and underlying molecular mechanisms, using air and N2 plasma jets from a micro nozzle array. Treatment with air or N2 plasma jets caused apoptotic death in human cervical cancer HeLa cells, simultaneously with depolarization of mitochondrial membrane potential. In addition, the plasma jets were able to generate reactive oxygen species (ROS), which function as surrogate apoptotic signals by targeting the mitochondrial membrane potential. Antioxidants or caspase inhibitors ameliorated the apoptotic cell death induced by the air and N2 plasma jets, suggesting that the plasma jet may generate ROS as a proapoptotic cue, thus initiating mitochondria-mediated apoptosis. Taken together, our data suggest the potential employment of plasma jets as a novel therapy for cancer

Intra-arterial delivery of triolein emulsion increases vascular permeability in skeletal muscles of rabbits

<p>Abstract</p> <p>Background</p> <p>To test the hypothesis that triolein emulsion will increase vascular permeability of skeletal muscle.</p> <p>Methods</p> <p>Triolein emulsion was infused into the superficial femoral artery in rabbits (triolein group, n = 12). As a control, saline was infused (saline group, n = 18). Pre- and post-contrast T1-weighted MR images were obtained two hours after infusion. The MR images were qualitatively and quantitatively evaluated by assessing the contrast enhancement of the ipsilateral muscles. Histologic examination was performed in all rabbits.</p> <p>Results</p> <p>The ipsilateral muscles of the rabbits in the triolein group showed contrast enhancement, as opposed to in the ipsilateral muscles of the rabbits in the saline group. The contrast enhancement of the lesions was statistically significant (p < 0.001). Histologic findings showed that most examination areas of the triolein and saline groups had a normal appearance.</p> <p>Conclusion</p> <p>Rabbit thigh muscle revealed significantly increased vascular permeability with triolein emulsion; this was clearly demonstrated on the postcontrast MR images.</p

Narrow-band imaging versus white light for the detection of proximal colon serrated lesions: a randomized, controlled trial

Background The value of narrow-band imaging (NBI) for detecting serrated lesions is unknown. Objective To assess NBI for the detection of proximal colon serrated lesions. Design Randomized, controlled trial. Setting Two academic hospital outpatient units. Patients Eight hundred outpatients 50 years of age and older with intact colons undergoing routine screening, surveillance, or diagnostic examinations. Interventions Randomization to colon inspection in NBI versus white-light colonoscopy. Main Outcome Measurements The number of serrated lesions (sessile serrated polyps plus hyperplastic polyps) proximal to the sigmoid colon. Results The mean inspection times for the whole colon and proximal colon were the same for the NBI and white-light groups. There were 204 proximal colon lesions in the NBI group and 158 in the white light group (P = .085). Detection of conventional adenomas was comparable in the 2 groups. Limitations Lack of blinding, endoscopic estimation of polyp location. Conclusion NBI may increase the detection of proximal colon serrated lesions, but the result in this trial did not reach significance. Additional study of this issue is warranted. (Clinical trial registration number: NCT01572428.

Hydroxyapatite Mineralization on the Calcium Chloride Blended Polyurethane Nanofiber via Biomimetic Method

Polyurethane nanofibers containing calcium chloride (CaCl2) were prepared via an electrospinning technique for the biomedical applications. Polyurethane nanofibers with different concentration of CaCl2 were electrospun, and their bioactivity evaluation was conducted by incubating in biomimetic simulated body fluid (SBF) solution. The morphology, structure and thermal properties of the polyurethane/CaCl2 composite nanofibers were characterized by means of scanning electron microscopy (SEM), field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetry. SEM images revealed that the CaCl2 salt incorporated homogeneously to form well-oriented nanofibers with smooth surface and uniform diameters along their lengths. The SBF incubation test confirmed the formation of apatite-like materials, exhibiting enhanced bioactive behavior of the polyurethane/CaCl2 composite nanofibers. This study demonstrated that the electrospun polyurethane containing CaCl2 composite nanofibers enhanced the in vitro bioactivity and supports the growth of apatite-like materials

Structure-Based Rational Design of a Toll-like Receptor 4 (TLR4) Decoy Receptor with High Binding Affinity for a Target Protein

Repeat proteins are increasingly attracting much attention as alternative scaffolds to immunoglobulin antibodies due to their unique structural features. Nonetheless, engineering interaction interface and understanding molecular basis for affinity maturation of repeat proteins still remain a challenge. Here, we present a structure-based rational design of a repeat protein with high binding affinity for a target protein. As a model repeat protein, a Toll-like receptor4 (TLR4) decoy receptor composed of leucine-rich repeat (LRR) modules was used, and its interaction interface was rationally engineered to increase the binding affinity for myeloid differentiation protein 2 (MD2). Based on the complex crystal structure of the decoy receptor with MD2, we first designed single amino acid substitutions in the decoy receptor, and obtained three variants showing a binding affinity (KD) one-order of magnitude higher than the wild-type decoy receptor. The interacting modes and contributions of individual residues were elucidated by analyzing the crystal structures of the single variants. To further increase the binding affinity, single positive mutations were combined, and two double mutants were shown to have about 3000- and 565-fold higher binding affinities than the wild-type decoy receptor. Molecular dynamics simulations and energetic analysis indicate that an additive effect by two mutations occurring at nearby modules was the major contributor to the remarkable increase in the binding affinities

Socioeconomic disparities in behavioral risk factors and health outcomes by gender in the Republic of Korea

<p>Abstract</p> <p>Background</p> <p>Few studies have examined socioeconomic disparities in health and behavioral risk factors by gender in Asian countries and in South Korea, specifically. We investigated the relationship between socioeconomic position (education, income, and occupation) and subjective and acute and chronic health outcomes and behavioral risk factors by gender, and compared results from 1998 and 2005, in the Republic of Korea.</p> <p>Methods</p> <p>We examined data from a nationally representative stratified random sample of 4213 men and 4618 women from the 1998 Korea National Health and Nutrition Examination Survey, and 8289 men and 8827 women from the 2005 Korea National Health and Nutrition Examination Survey using General Linear Modeling and multiple logistic regression methods.</p> <p>Results</p> <p>Controlling for behavioral risk factors (smoking, drinking, obesity, exercise, and sleep), those in lower socioeconomic positions had poorer health outcomes in both self-reported acute and chronic disease and subjective measures; differences were especially pronounced among women. A socioeconomic gradient for education and income was found for both men and women for morbidity and self-reported health status, but the gradient was more pronounced in women. In 1998, the odds ratios (ORs) of higher morbidity for illiterate vs. college educated females was 5.4:1 and 1.9:1 for females in the lowest income quintile vs. the highest. The OR for education decreased in 2005 to 2.9:1 and that for income quintiles remained the same at 1.9:1. The OR of lower self-reported health status for illiterate vs. college educated females was 2.9:1 and 1.6:1 for females in the lowest income quintile vs. the highest in 1998, and 3.3:1 and 2.3:1 in 2005.</p> <p>Conclusions</p> <p>Among Korean adults, men and women in lower socioeconomic position, as denoted by education, income, and somewhat less by occupation, experience significantly higher levels of morbidity and lower self-reported health status, even after controlling for standard behavioral risk factors. Disparities were more pronounced for women than for men. Efforts to reduce health disparities in South Korea require attention to the root causes of socioeconomic inequality and gender differences in the impact of socioeconomic position on health.</p

Serum amyloid A inhibits RANKL-induced osteoclast formation

When mouse bone marrow-derived macrophages were stimulated with serum amyloid A (SAA), which is a major acute-phase protein, there was strong inhibition of osteoclast formation induced by the receptor activator of nuclear factor kappaB ligand. SAA not only markedly blocked the expression of several osteoclast-associated genes (TNF receptor-associated factor 6 and osteoclast-associated receptor) but also strongly induced the expression of negative regulators (MafB and interferon regulatory factor 8). Moreover, SAA decreased c-fms expression on the cell surface via shedding of the c-fms extracellular domain. SAA also restrained the fusion of osteoclast precursors by blocking intracellular ATP release. This inhibitory response of SAA is not mediated by the well-known SAA receptors (formyl peptide receptor 2, Toll-like receptor 2 (TLR2) or TLR4). These findings provide insight into a novel inhibitory role of SAA in osteoclastogenesis and suggest that SAA is an important endogenous modulator that regulates bone homeostasis.open

No association between polymorphisms of WNT2 and schizophrenia in a Korean population

<p>Abstract</p> <p>Background</p> <p>Wingless-type MMTV integration site family member 2 (WNT2) has a potentially important role in neuronal development; however, there has yet to be an investigation into the association between single nucleotide polymorphisms (SNPs) of <it>WNT2 </it>and schizophrenia. This study aimed to determine whether certain SNPs of <it>WNT2 </it>were associated with schizophrenia in a Korean population.</p> <p>Methods</p> <p>e genotyped 7 selected SNPs in the <it>WNT2 </it>gene region (approximately 46 Kb) using direct sequencing in 288 patients with schizophrenia and 305 healthy controls.</p> <p>Results</p> <p>Of the SNPs examined, one SNP showed a weak association with schizophrenia (p = 0.017 in the recessive model). However, this association did not remain statistically significant after Bonferroni correction.</p> <p>Conclusion</p> <p>The present study does not support a major role for <it>WNT2 </it>in schizophrenia. This could be due to the size of the population. Therefore, additional studies would be needed to definitively rule out the gene's minor effects.</p