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Macroalgal canopies, which provide nutrients and habitats for many invertebrates and fishes in coastal waters, are disappearing worldwide. The simultaneous assessment of changes in macroalgae and fish distribution before and after coastal desertification, including deeper coastal waters where beyond macroalgae growth need attention. Therefore, we investigated their spatial distribution in the coastal waters off southwestern Japan in late autumn and winter using the acoustic method combined with visual observation. The number of fish schools was higher in late autumn than in winter, while they had similar acoustic backscattering strength (Sv) and school size, tended to be distributed in shallower waters. The number was lower after the macroalgae disappeared in both seasons, while the average Sv was higher, and the size was larger. They were distributed in similar water depths during the winter season. Fewer fish schools and higher Sv were observed in deeper waters after the macroalgae disappeared. We concluded that more fishes moved to shallower waters in the autumn than in the winter because of higher water temperatures. Macroalgae benefited small juvenile fishes in both shallow and deep coastal waters. Further studies on the distribution of specific species are expected for the assessment and restoration of the macroalgal ecosystem. [ABSTRACT FROM AUTHOR]

We report the unstable surface feature in nanometer-scale of diamondlike carbon (DLC) films deposited through C[sub 60] evaporation with simultaneous bombardment of 1.5 keV Ne[sup +] ions. The periodical ripples, commonly appearing in postprocessing of the deposited films, form directly at 550°C and 700°C, which is qualitatively consistent with the theoretical model based on sputtering yield variation with surface curvature. A dramatic transition from ripple surface to mounding roughening occurs at 400°C. The graphitization with increasing temperature induces the different dominant smoothening mechanisms, which is responsible for the morphological change observed. Further, the calculations of height-height correlation function show that the roughness exponents are around 0.8 at 200°C and 400°C, implying self-affinity of roughened surfaces. This study exhibits a potential of ion beam assisted deposition to tune DLC morphologies by controlling the deposition parameters to drive the competition between ion erosion and film deposition. [ABSTRACT FROM AUTHOR]

Diamond-like carbon (DLC) films were prepared with mass-selected C[sup +], CH[sup +][sub 2], CH[sup +][sub 3], and CH[sup +][sub 4] ions, C, and the dependence of film microstructures and properties on ion species was investigated with micro-Raman spectroscopy, optical band gap measurement and atomic force microscopy (AFM). The results indicate that highly sp³ bonded DLC films are achieved using carbon and hydrocarbon ions with ion energy of 100 eV. AFM results exhibit that the surface roughness for these films is very low, which is associated with the formation of a dense diamond-like phase as suggested by the subplantation model. The thermal stability of the films were investigated in the temperature region of 200-800 °C. Raman measurements show that the D peak evolves at much lower temperatures for the film prepared with CH[sup +][sub 4] than that for the film prepared with C[sup +] ions during annealing. The results indicate that hydrogen-free carbon films have a much better thermal stability than hydrogenated carbon films. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide (SC-CO2) extraction of fucoxanthin is more advantageous over conventional solvent extraction as it is less toxic, less hazardous to the environment and preserves the bioactivity of fucoxanthin. A face-centered central composite design (FCCCD) based on response surface methodology (RSM) was employed for SC-CO2 extraction of oils and fucoxanthin from the brown seaweed Sargassum binderi, with ethanol as a co-solvent. Three independent parameters namely, extraction temperature (A: 40, 50, 60°C), pressure (B: 2900, 3625, 4350 psig and particle size (C: 90, 500 and 1000 µm) were investigated to optimize extraction oil yields (EOY) and fucoxanthin yields (FY). A regression model was developed, tested for quality of fit (R²) and expressed in the form of 3D response surface curve and 2D contour. The optimum extraction conditions were obtained at extraction temperature (A) 50°C, pressure (B) 3625 psig and particle size (C) 500 µm. Under these conditions, optimal EOY and FY were 10.04 mg/g and 3188.99 µg/g, respectively. The difference between the lowest and the highest response in EOY and FY were 5.44 - 10.04 mg/g and 2109.10 - 3188.90 µg/g, respectively. The lowest yields were identified at 60°C, 2900 psig and 1000 µm. The regression models generated showing interactions between the variables and EOY and FY response were significant as tested by ANOVA (p < 0.0005 and p < 0.0007, respectively) with high R² values (0.9848 and 0.9829, respectively). Interactions between the parameters had a strong synergistic effect on EOY and FY values, as indicated by the 3D response surface curve and 2D contour. The experimental results matched the predicted results closely. This indicated the suitability of the models developed and the success of FCCCD under RSM in optimizing the S. binderi extraction conditions. [ABSTRACT FROM AUTHOR]

Aim: To examine the responses of mouse odontoblast-lineage cell line (OLC) cultures to xylitol-induced hypertonic stress. Methodology: OLCs were treated with xylitol, sucrose, sorbitol, mannitol, arabinose and lyxose. Cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium assay. The expression of transient receptor potential vanilloids (TRPV) 1, 3 and 4 was detected using a reverse transcriptase-polymerase chain reaction (RT-PCR) assay. The expression of aquaporin (AQP) 2 was detected using immunofluorescence and Western blotting analysis. The expression of interleukin-6 (IL-6) under xylitol-induced hypertonic stress was assessed using an enzyme-linked immunosorbent assay (ELISA). Small interfering ribonucleic acid (siRNA) for AQP-2 was used to inhibition assay. Results: Xylitol-induced hypertonic stress did not decrease OLC viability, unlike the other sugars tested. OLCs expressed TRPV1, 3 and 4 as well as AQP2. Xylitol inhibited lipopolysaccharide (LPS)-induced IL-6 expression after 3 h of hypertonic stress. TRPV1 mRNA expression was upregulated by xylitol. Costimulation with HgCl2 (AQP inhibitor) and Ruthenium red (TRPV1 inhibitor) decreased cell viability with xylitol stimulation. OLCs treated with siRNA against TRPV1 exhibited decreased cell viability with xylitol stimulation. Conclusion: OLCs have high-cell viability under xylitol-induced hypertonic stress, which may be associated with TRPV1 and AQP2 expressions. [ABSTRACT FROM AUTHOR]

Carotenoids are a class of naturally occurring pigment, carrying out important biological functions in photosynthesis and involved in environmental responses including nutrition in organisms. Saproxanthin and myxol, which have monocyclic carotenoids with a γ-carotene skeleton, have been reported to show a stronger antioxidant activity than those with β-carotene and zeaxanthin. In this research, a yellow-orange bacterium of strain 11shimoA1 (JCM19538) was isolated from a seaweed collected at Nabeta Bay (Shizuoka, Japan). The 16S rRNA gene sequence of strain 11shimoA1 revealed more than 99.99 % similarity with those of Jejuia pallidilutea strains in the family Flavobacteriaceae. Strain 11shimoA1 synthesized two types of carotenoids. One of them was (3 R, 3' R)-zeaxanthin with dicyclic structure and another was identified as (3 R, 2' S)-2′-isopentenylsaproxanthin, a novel monocyclic carotenoid with pentenyl residue at C-2′ position of saproxanthin, using FAB-MS, H NMR, and CD analyses. Culturing strain 11shimoA1 in an alkaline medium at pH 9.2 resulted in a markedly increased in production of 2′-isopentenylsaproxanthin per dry cell weight, but a decreased in zeaxanthin production as compared to their respective production levels in medium with pH 7.0. These carotenoids are likely to play some roles in the adaptation of the bacterium to the environmental conditions. [ABSTRACT FROM AUTHOR]

Practical superconductive (SC) wires such as the Nb3Sn and Nb3Al strands used in fusion reactors are typical composite materials consisting of brittle superconducting intermetallic compounds. Thermally induced strain is inevitably generated in the composite due to the different coefficients of thermal expansion and different moduli of elasticity among the constituent components. In order to evaluate quantitatively the thermal strain, local strain measurements during heating by means of quantum beams, and room temperature tensile tests were carried out. The stress versus strain curves of both Nb3Sn and Nb33 typical elasto-plastic behavior, which could be numerically evaluated on the basis of the rule of mixtures. The local strain exerted on SC filaments along the axial direction was compressive at room temperature and tensile at high temperatures, which is common for Nb3Sn and Nb3Al strands. Their temperature dependence was numerically evaluated by means of the iteration method. As a whole, it has been established that the temperature dependence of thermal strain can be reproduced well by the numerical calculation proposed here. It is pointed out that the thermal strain in SC filaments is affected by the creep phenomenon at high temperatures above a threshold temperature. [ABSTRACT FROM AUTHOR]

Background: Arteriovenous shunting visualized by angiography is one of the major features of glioblastomas, and the visualization is dependent on the presence of extensive shunting. Extensive arteriovenous shunting is associated with the risk of poorly controlled intraoperative bleeding. When a tumor with extensive arteriovenous shunting is located in close proximity to the eloquent regions of the brain, a meticulous surgical procedure is necessary. In the present study, the site-oriented visualization of angiographical arteriovenous shunting was evaluated from the perspective of surgical treatment, with a particular focus on the perisylvian region that is in close proximity to motor and language regions (dominant hemisphere), as well as large arteries and veins. Methods: Twenty-six consecutive patients underwent a resection of glioblastoma between February 2007 and September 2012. All patients were presurgically examined using digital subtraction angiography. The patients were subdivided into the following two groups based on the location of the tumor: 1) perisylvian glioblastoma (18 patients) and 2) non-perisylvian glioblastoma (eight patients). Angiography to detect the arteriovenous shunting was performed. In addition, the number of intratumoral vessels, tumor proliferative activity (MIB-1 labeling index), and volume of intraoperative bleeding were evaluated and compared between the two groups. Results: Angiographical arteriovenous shunting was definitively visualized in 13 of 18 (72 %) perisylvian glioblastomas, in contrast to only one of eight (13 %) non-perisylvian glioblastomas ( p = 0.007). There were no significant differences between the two groups with respect to the number of intratumoral vessels, MIB-1 labeling index, and volume of intraoperative bleeding. However, massive intraoperative bleeding of > 2,000 mL occurred in one perisylvian glioblastoma patient. Conclusions: Glioblastomas in the perisylvian region tend to be associated with extensive arteriovenous shunting that can be definitively visualized by performing an angiography. Because arteriovenous shunting carries the risk of intraoperative bleeding, perisylvian glioblastomas-particularly in the dominant hemisphere-should be resected with a meticulous surgical procedure and strategy. [ABSTRACT FROM AUTHOR]

Acoustic telemetry and microchemical analysis of otolith strontium-calcium ratios were used to evaluate how exotic brown trout Salmo trutta have responded to Japanese riverine environments of south-western Hokkaido by observing their migratory patterns. The existence of anadromous S. trutta was also verified. Most S. trutta caught in rivers for otolith analysis were freshwater residents (95·6%), whereas those caught in the sea were mainly smolts (91·3%), which had just migrated from rivers during spring. Anadromous S. trutta ( n = 6) were captured in rivers and in the sea, confirming the existence of mature pre- and post-spawning fish. According to telemetry results, both mature and immature S. trutta used the river in winter, and their estimated sea-run timings showed individual differences. Through the combination of these two methods, migratory patterns on various spatio-temporal scales were observed. This first documentation of the presence of both male and female anadromous S. trutta in the same region within Japan indicated the risk of further colonization of exotic S. trutta via oceanic migration. [ABSTRACT FROM AUTHOR]

The purpose of the present study is to demonstrate the correlation between the force applied to a ball and the joint motion of the hip, trunk, shoulder and elbow in adolescent baseball players. The subjects were 15 adolescent baseball players (13.7±0.8 yrs) and 15 college-age baseball players (22.1±1.5). Pitching motion images were captured by three high-speed cameras, and 3D analysis established by the direct leaner translation method was performed to obtain the angles and the angular velocity of each joint, as well as the acceleration of the wrist toward the target at ball release (Acc). In the adolescent players, a significant linear correlation was found between Acc and trunk rotation angle (r=-0.59), elbow extension angle (r=-0.75), shoulder internal rotation velocity (r=-0.76) and elbow extension velocity (r=-0.61). In the college-age players, a significant linear correlation was found between Acc and hip adduction velocity (r=-0.51) and elbow extension velocity (r=-0.61). The finding indicates that adolescent players may depend more on the upper extremity motion than the hip joint motion when pitching. Coaches and athletic trainers may need to focus on the hip joint motion in order to prevent pitching injuries among adolescent baseball players. [ABSTRACT FROM AUTHOR]

We and others have reported that human NF-κB inhibitor-like-1 (NFKBIL1) was a putative susceptible gene for autoimmune diseases such as rheumatoid arthritis (RA). However, its precise role in the pathogenesis of RA is still largely unknown. In this study, we generated transgenic mice expressing human NFKBIL1 (NFKBIL1-Tg) and examined whether NFKBIL1 plays some role(s) in the development of autoimmune arthritis. In both a collagen-induced arthritis model and a collagen antibody-induced arthritis model, NFKBIL1-Tg mice showed resistance to arthritis compared to control mice, indicating that the gene product of NFKBIL1 was involved in the control of thusly induced arthritis. Total spleen cells of NFKBIL1-Tg mouse showed decreased proliferation to mitogenic stimuli, consistent with its resistance to arthritis. Unexpectedly, purified T cells of NFKBIL1-Tg mouse showed increased proliferation and cytokine production. This apparent discrepancy was accounted for by the impaired functions of antigen-presenting cells of NFKBIL1-Tg mouse; both T/B cell-depleted spleen cells and bone marrow-derived dendritic cells of the Tg mouse induced less prominent proliferation and IL-2 production of T cells. Furthermore, dendritic cells (DCs) derived from NFKBIL1-Tg mouse showed lower expression of co-stimulatory molecules and decreased production of inflammatory cytokines when they were activated by lipopolysaccharide. Taken together, these results indicated that NFKBIL1 affected the pathogenesis of RA at least in part through the regulation of DC functions. [ABSTRACT FROM AUTHOR]

The study identified seasonal habitat use by endangered adult Sakhalin taimen Hucho perryi and the environmental characteristics of their habitat (water depth, amount of riparian forest and sinuosity). Fifteen adult H. perryi with acoustic tags were tracked by towing an acoustic receiver with a canoe in the Bekanbeushi River system in eastern Hokkaido Island, Japan, during each month from late April to late November 2008. Individuals mainly used midstream (shallower than downstream) habitats in all seasons. These locations were generally characterized by relatively dense riparian forests and high sinuosity, indicating the presence of pools. In spring, individuals used habitats with less riparian forest cover compared to mean value of the river channel. From spring to autumn, adult H. perryi selected limnologically complex habitats with meandering channels. From summer to autumn, individuals selected habitats with more riparian forest cover. The inverse relationship between H. perryi detection and riparian forest area in spring was a result of seasonal defoliation in deciduous riparian forests. [ABSTRACT FROM AUTHOR]

This study aimed to demonstrate each joint angle at the maximum external rotation of the shoulder complex during the throwing of adolescent baseball players. The subjects were 15 adolescent baseball players (13.7±0.8 yrs) and 15 collegiate baseball players (22.1±1.5yrs). Throwing motion images were captured by three high-speed cameras, and a 3D analysis established by the direct leaner translation method was performed to obtain the shoulder external rotation, the glenohumeral external rotation (ER), and scapular posterior tilt angles. In the adolescent baseball players, the mean (±SD) value of the maximum external rotation angle (MER) was 141 ±15°, whereas the mean values of the glenohumeral ER and the scapula posterior tilt angles at the MER were 109±15° and 31±14°. Conversely, each angle of the college baseball players was 144±11°, 107±15°, and 29±14° respectively. There were no differences between the adolescent players and the college players. The adolescent players may need the same shoulder joint angles as the college players [ABSTRACT FROM AUTHOR]

A high prevalence of anterior cruciate ligament (ACL) injury has been reported in judo. However, there has been very little research concerning events preceding the injury. Therefore, the objective of this study was to determine the common situations and mechanisms of ACL injury in judo. A total of 60 cases of ACL injuries that had occurred during judo competitions or practice were investigated through interview conducted by a single certified athletic trainer who has 20 years of judo experience. We then obtained information regarding the situation and mechanism in which the ACL injury occurred. The direct contact mechanism was observed more frequently than the other injury mechanisms in the ACL incidence in judo. In addition, the number of ACL injuries was significantly higher when the subject was attacked by the opponent than when counterattacked or when attempting to attack. In addition, osoto-gari was the leading technique that directly caused ACL injury incident among the subjects. [ABSTRACT FROM AUTHOR]

Free radicals and singlet oxygen are responsible for oxidative stress related diseases and many natural compounds are known to have antioxidant properties. In this study, extracts from brown and red seaweeds of Indian origin were evaluated for their ability to scavenge different radicals and quench singlet oxygen. The crude extract in methanol and its fractions in different solvents were evaluated for their activity. The methanol extract and its fractions from brown seaweed exhibited higher 2,2′-azinobis(3-ethylbenzothizoline-6-sulfonic acid) radical scavenging activity with more than 90% scavenging in butanol and ethyl acetate fractions and correlated with polyphenol content. There was a significant difference (p≤0.001) in hydroxyl radical scavenging activity between different fractions of the same seaweed. Among the crude extracts, extract from Gracilaria corticata showed the highest (14.0%) activity. Crude extract from brown seaweeds showed higher peroxyl radical scavenging activity compared to red seaweeds. In fractions from brown seaweed extracts, highest activity was observed in ethyl acetate fraction (>88%) followed by hexane fraction (>40 %). Ethyl acetate fraction from crude extract showed higher inhibitory activity against hemoglobin induced linoleic acid oxidation. Singlet oxygen quenching activity of the crude extract from brown seaweed was lower (<13%) compared to red seaweeds (16.4–20.5%). [ABSTRACT FROM AUTHOR]

The purpose of the present study was to demonstrate the correlation between MER during throwing and each range of motion (ROM) of the shoulder complex, which consist of external rotation of glenohumeral joint and posterior tipping of the scapula in baseball players. The subjects were 19 collegiate baseball players. A three-dimensional analysis was performed to obtain the MER. The ROM of the external rotation of the shoulder complex (ER-ROM), ROM of the external rotation of the glenohumeral joint (GHE), and ROM of the posterior tipping of the scapula (SPT) were also passively measured. The mean (± SD) value of the MER was 150 ± 10°. The mean (± SD) values of the ER-ROM, GHE, and SPT were 135 ± 12°, 89 &plumsn; 12°, and 32 &plumsn; 7° respectively. Significant linear correlations were found between SPT and MER (r = 0.48), ER-ROM (r = 0.65). No significant correlations were found between GHE and MER and ER-ROM. The finding may indicate the importance of scapula motion more than glenohumeral joint motion for MER and ROM of the shoulder complex. [ABSTRACT FROM AUTHOR]

Measurement of brachial-ankle pulse wave velocity (baPWV) is recognized as a simple and practical method for assessing arterial stiffness. We determined whether the baPWV of adolescents is affected by obesity and its associated metabolic risk variables. A cross-sectional sample of 754 apparently healthy adolescents (383 men and 371 women), aged 15–17 years, was recruited for this study. baPWV was measured by a simple automatic oscillometric technique. Adiposity measures, blood pressure, serum lipoproteins, fasting glucose and insulin were evaluated. The baPWV of the adolescents was significantly higher in men than in women and increased with age in both genders. After being statistically adjusted for age and gender, baPWV was significantly correlated with body mass index, percent body fat, waist-to-height ratio, systolic and diastolic blood pressures, mean arterial pressure, triglycerides, high-density lipoprotein cholesterol (HDL-C), atherogenic index, glucose, insulin, and homoeostasis model assessment of insulin resistance (HOMA-IR). In the multivariate regression analysis, mean arterial pressure, atherogenic index, HOMA-IR, systolic blood pressure and age were found to be significant determinants of baPWV (P<0.001). An increasing number of clustered risk variables, including high values (>gender-specific top quartiles) of waist-to-height ratio, mean arterial pressure, atherogenic index and HOMA-IR showed a graded association with baPWV (P<0.001 for trend). These results suggest that obesity and its associated metabolic abnormalities are important factors in the increased baPWV of adolescents and that baPWV may be useful in investigating early arterial wall changes in this population.Journal of Human Hypertension (2009) 23, 444–450; doi:10.1038/jhh.2008.143; published online 11 December 2008 [ABSTRACT FROM AUTHOR]

Trans and conjugated fatty acids may exhibit either beneficial or detrimental bioactive effects depending on their metabolic properties. This study was conducted to elucidate if isomerization and conjugation of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) demonstrate more favorable bioactivity on lipid metabolism compared to unmodified EPA and DHA. The effects of dietary intake of trans and conjugated forms of EPA and DHA on lipid metabolism were evaluated in animal trials and compared to a control group fed soybean oil. None of the experimental diets showed significant differences from the control in terms of body weight; however, the white adipose tissue weight of rodents fed trans DHA, conjugated EPA (CEPA), and conjugated DHA (CDHA) was significantly lower than the control. Triacylglycerol levels in plasma were significantly decreased in groups fed trans DHA (17.2 mg/dL) and CDHA (31.9 mg/dL) relative to the control (51.3 mg/dL). The total cholesterol concentrations were significantly lower than the control (68.0 mg/dL) in all experimental groups (47.3 to 53.7 mg/dL) except CEPA (58.3 mg/dL). Fatty acid compositions of lipids extracted from rodent livers were influenced by the dietary fatty acid profiles, with all groups showing higher concentrations of stearic acid and lower levels of linoleic acid compared to the control. Rodents fed trans DHA did not have detectable levels of these fatty acid isomers in their livers, suggesting either quick metabolism or a difficulty with bio-absorption. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that resistance training exercise under unstable conditions decreases the isometric force output, yet little is known about its influence on muscular outputs during dynamic movement. The objective of this study was to investigate the effect of an unstable condition on power, force, and velocity outputs during the bench press. Twenty male collegiate athletes (mean age, 21.3 +/- 1.5 years; mean height, 167.7 +/- 7.7 cm; mean weight, 75.9 +/- 17.5 kg) participated in this study. Each subject attempted 3 sets of single bench presses with 50% of 1 repetition maximum (1RM) under a stable condition with a flat bench and an unstable condition with a Swiss ball. Acceleration data were obtained with an accelerometer attached to the center of a barbell shaft, and peak outputs of power, force, and velocity were computed. Although significant loss of the peak outputs was found under the unstable condition (p < 0.017), their reduction rates remained relatively low, approximately 6% for force and 10% for power and velocity outputs, compared with previous findings. Such small reduction rates of muscular outputs may not compromise the training effect. Prospective studies are necessary to confirm whether the resistance training under an unstable condition permits the improvement of dynamic performance and trunk stability. [ABSTRACT FROM AUTHOR]

Services are perishable and are simultaneously produced and consumed. A reservation is a traditional and effective means for coordinating service demand and supply. In recent years, computerized reservation systems have been used widely by many service vendors such as airline companies and hotels to satisfy their customer's demands and improve their profits. In this paper, we propose and describe a more flexible reservation method called "YuuZuu" reservation that motivates cooperation among customers with different preferences for services. It increases utilization of vendor-provided services. The DREAM reservation system, which is an implementation of "YuuZuu" reservation, comprises three functions: (1) reservation allocation, (2) demand analysis, and (3) price optimization. Preliminary experiments show that the DREAM reservation system outperforms a standard reservation system when some customers are insistent upon detailed preferences and others are not, which, we believe, reflects real-world conditions. [ABSTRACT FROM PUBLISHER]

Background: We have previously reported that troglitazone, a synthetic ligand for peroxisome proliferator-activated receptor γ (PPARγ), and bitter gourd seed oil rich in 9cis,11trans,13trans-conjugated linolenic acid (9c,11t,13t-CLN) prevent colon carcinogenesis. To evaluate the chemotherapeutic effect and potency of these compounds on colon cancer cells, we investigated their antiproliferative and apoptosis-inducing effects using different human colon cancer cell lines. Methods: The antiproliferative and apoptosis-inducing effects of troglitazone and 9c,11t,13t-CLN were evaluated and compared using HT-29, DLD-1 and Caco-2 cells at different stages of enterocytic differentiation. Results: Troglitazone and 9c,11t,13t-CLN decreased cell viability and induced apoptosis in three colon cancer cell lines. The susceptibility of HT-29, which expresses PPARγ at high levels, to troglitazone and 9c,11t,13t-CLN was higher than that of Caco-2 cells with low levels of PPARγ. Conclusion: Troglitazone and 9c,11t,13t-CLN exhibited more effective chemotherapeutic effects on HT-29 cells than on Caco-2 cells. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Toll-like receptor 4 (TLR4), which recognizes lipopolysaccharides, plays an important role in the innate immune response. In this study, we investigated the role of TLR4 in the development of experimental colitis with regard to the biological actions of macrophage migration inhibitory factor (MIF) using TLR4 null (–/–) mice. TLR4–/– mice were given 2% dextran sulphate sodium (DSS) in drinking water to induce colitis, which was clinically and histologically as severe as that seen in wild-type (WT) mice. The level of tumour necrosis factor (TNF)-α in colon tissues was increased in WT mice but unchanged in TLR4–/– mice. The level of myeloperoxidase (MPO) activity in colon tissues was increased by DSS administration in both TLR4–/– and WT mice. The expression of MIF was up-regulated in the colons of TLR4–/– mice with acute DSS-induced colitis. An anti-MIF antibody significantly suppressed colitis and elevation of matrix metalloproteinase-13 in TLR4–/– mice. The current results obtained from TLR4–/– mice provide evidence that MIF plays a critical role in the development of acute DSS-induced colitis. [ABSTRACT FROM AUTHOR]