Enterococcus faecalis, a gram-positive bacterium, has been implicated in endodontic infections, particularly in chronic apical periodontitis. Proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), are involved in the pathogenesis of these apical lesions. E. faecalis has been reported to stimulate macrophages to produce TNF-α. The present study investigated the mechanisms involved in TNF-α production by a murine macrophage cell line, RAW 264.7 in response to exposure to E. faecalis. Both live and heat-killed E. faecalis induced high levels of gene expression and protein release of TNF-α. Treatment of RAW 264.7 cells with cytochalasin D, an inhibitor of endocytosis, prevented the mRNA up-regulation of TNF-α by E. faecalis. In addition, antioxidant treatment reduced TNF-α production to baseline levels. Inhibition of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein (MAP) kinase also significantly attenuated E. faecalis-induced TNF-α expression by RAW 264.7 cells. Furthermore, activation of NF-κB and AP-1 in RAW 264.7 cells was also stimulated by E. faecalis. These results suggest that the phagocytic uptake of bacteria is necessary for the induction of TNF-α in E. faecalis-stimulated macrophages, and that the underlying intracellular signaling pathways involve reactive oxygen species, ERK, p38 MAP kinase, NF-κB, and AP-1.

Effects of Vegemil® containing soybean proteins and isoflavones on the growth and bone density of broiler chickens were investigated. One-week-old male and female Arbor Acres broiler chickens were fed on Vegemil® A containing 3% soybean proteins and 162 ppm isoflavones, instead of water, for 30 days and their growth indices (body weight, leg weight and femur length) and bone density were analyzed. The body weight gains in male and female chickens were increased by 15.6% and 31.7%, respectively, following feeding Vegemil® A compared to normal water. Vegemil® A increased leg weight as well as femur length of females by 22.9% and 15.0%, respectively. In addition, Vegemil® A feeding enhanced femoral bone density by 21.3% in comparison with water feeding. Therefore, it is suggested that Vegemil® A not only facilitates body growth, but also strengthens bone density of normal chickens, and that it could be a promising candidate for the improvement of infant growth and for the prevention of menopausal osteoporosis.

Porphyromonas gingivalis is a major etiologic agent of chronic periodontitis and cytokines produced by macrophages play important roles in the pathogenesis of periodontal diseases. In this study we investigated the cytokine response of phorbol myristate acetatedifferentiated THP-1 cells exposed to P. gingivalis. Compared with the prominent cell wall components of P. gingivalis (lipopolysaccharide and the major fimbrial protein FimA), live P. gingivalis stimulated much higher levels of cytokine production. In addition, whereas low multiplicity of infection challenges (MOI=10) of P. gingivalis 381 stimulated high levels of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β, high dose challenges with this bacterium (MOI = 100) resulted in a substantially diminished production of MCP-1 and IL-6. Moreover, high MOI P. gingivalis challenges achieved only low levels of induction of MCP-1 and IL-6 mRNA. The decreased production of MCP-1 and IL-6 appeared to be mediated by P. gingivalis proteases, because high MOI challenges with congenic protease mutant strains of this microorganism (MT10 and MT10W) did not result in a diminished production of MCP-1 and IL-6. Similar to its protease mutant strains, leupeptin (a protease inhibitor)- treated P. gingivalis at high doses induced high levels of MCP-1 production. To examine the mechanisms underlying the diminished production of MCP-1 by P. gingivalis proteases, the activation of mitogen-activated protein (MAP) kinases and NF-xB was compared between the 381 and MT10W strains. Whilst high doses of both 381 and MT10W similarly activated the three members of the MAP kinase family, the DNA binding activity of NF-xB, as revealed by gel shift assays, was greatly increased only by MT10W. Taken together, our data indicate that P. gingivalis stimulates the production of high levels of TNF-α, IL-1β, IL-6, and MCP-1 but that high dose challenges with this bacterium result in a diminished production of MCP-1 and IL-6 via the protease-mediated suppression of NF-B activation in THP-1 macrophagic cells.

지하수나 폐수 등에 포함된 독성을 가진 음이온류나 양이온류 등의 유독물질을 경제적으로 처리하는데 탁월한 분리기능을 가진 것으로 알려진 전기투석공정에 사용하기 위해 음이온 교환 복합막을 제조하여 그 전기화학적인 특성을 조사하였다. 다양한 조성의 vinylbenzylchloride (VBC)와 divinylbenzene (DVB) 그리고 α,α-azobis(isobutyronitrile) (AIBN)으로 이루어진 단량체 용액에 다공성 지지체인 poly(ethylene) (PE)을 함침한 후 열중합 가교시켜 poly(VBC-DVB)/PE 복합막을 생성한 다음 trimethylamine(TMA)과 acetone을 이용해 음이온 교환기(-N + (CH3)3)를 함유하는 복합막을 제조하였다. 음이온 교환막 제조시 VBC/DVB의 비율과 TMA/Acetone의 비율에 따른 막의 함수율, 이온교환용량(IEC) 및 전기저항을 조사하였다. 그 결과 제조된 막들은 사용된 PE지지체의 얇은 막두께에 기인하여 아스톰사의 상용화 음이온 교환막(AMX)보다 높은 IEC와 낮은 전기저항 및 낮은 함수율 등을 나타내는 것을 확인할 수 있었다. 본 실험에서 제조된 복합막은 저렴한 제조비용과 우수한 전기화학적 특성으로 정수 및 폐수처리를 위한 전기투석공정에 충분히 적용될 수 있음을 알 수 있었다.

While the professional literature abounds with the values of feedback on L2 language writings, few researchers have investigated the differential effects of types of feedback on the writing improvements in terms of proficiency levels. The purpose of the study was three-fold: to examine (1) the effects of three types of feedback, teacher, peer, and self-review on sixteen Korean college students" writing improvements; (2) the relationships between feedback types and proficiency levels; and (3) students" opinions on the feedback types such as preferences and reasons. The results showed that all types of feedback helped students improve their writings through revisions, but the effects of feedback differ from feedback type to type. The effects of teacher and peer review were significantly beneficial for students" writing, while the self-review was the least effective. In addition, the more advanced writers benefit from the peer or self-review, while the less proficient writers improved their writing from the teacher feedback, even though most of the students prefer the teacher feedback to the other types of feedback, peer and self-review. The theoretical background and pedagogical implications are discussed.

SAGE technique is a sequenced-based approach that identifies which genes are expressed and quantifies their level of expression. The SAGE catalog of gene expression for a given cell or tissue is defined as the 'transcriptome'. With a goal of obtaining a set of quantitative information of expressed genes of posterior silk gland (PSG) of silkworm, we have generated a SAGE tag library from the PSGat day 4 of 5th instars of Bombyx mori. In this study, atotal of 2,406 tags were identified, representing 682 unique transcripts. Of these SAGE tags, 1,982 tags were detected twice or more accounted for 82% of the total tag population, whereas 445 tags were detected only once accounted for 18% of the total tag population. Four percent (27 tags) of the unique tags were detected at least ten times each, which corresponds to a representation of more than 53% of the total tag population. In addition, we have discussed a comparative aspect of the transcript abundance between expressed sequenced tags (ESTs) and the SAGE tags.

The insect baculovirus expression vector system (BEVS) is useful for the production of biologically active recombinant proteins. However, the overexpression of foreign proteins in this system often results in misfolded proteins and the formation of protein aggregates. To overcome this limitation, we have developed a versatile baculovirus expression and secretion system using the Bombyx mori protein disulfide isomerase (bPDI) as a fusion partner. bPDI gene fusion improved the secretion and antibacterial activity of recombinant nuecin proteins. Thus, bPDI gene fusion is a useful addition to the BEVS for the large-scale production of bioactive recombinant proteins.

To maintain optimal performance in a floor heating system, the elements of system must be consisted of the adequate structure in order that the heat flow is efficiently transmitted from the floor structure to indoor space. The aims of this study is to propose the optimal structure type and present applicable design data of a floor heating system. The design data suggested in this study can be applied to cooperate energy efficiency design as well as comfortable indoor thermal environment in the early design stage.

We calculate the evolution of multiple supernova (SN) explosions inside a pre-exiting bubble blown up by winds from massive stars, using one-dimensional hydrodynamic simulations including radiative cooling and thermal conduction effects. First, the development of the wind bubble driven by collective winds from multiple stars during the main sequence is calculated. Then multiple SN explosion is loaded at the center of the bubble and the evolution of the SN remnant is followed for 106 years. We find the size and mass of the SN-driven shell depend on the structure of the pre-existing wind bubble as well as the total SN explosion energy. Most of the explosion energy is lost via radiative cooling, while about 10% remains as kinetic energy and less than 10% as thermal energy of the expanding bubble shell. Thus the photoionization and heating by diffuse radiation emitted by the shock heated gas is the most dominant form of SN feedback into the surrounding interstellar medium.

In the present study, electrospun PAN precursor webs and the stabilized and carbonized nanofiber webs processed under different heat-treatment conditions were characterized by means of weight loss measurement, elemental analysis, scanning electron microscopy (SEM), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), thermogravimentric analysis (TGA), and X-ray diffraction (XRD) analysis. The result indicated that stabilization and carbonization processes with different temperatures and heating rates significantly influenced the chemical and morphological characteristics as well as the thermal properties of the stabilized and then subsequently carbonized nanofiber webs from PAN precursor webs. It was noted that the filament diameter and the carbon content of a carbonized nanofiber web as well as its weight change may be effectively monitored by controlling both stabilization and carbonization processes.