Differences in fat-free mass and muscle thicknesses at various sites according to performance level among judo athletes.

The purpose of this study was to investigate differences in fat-free mass and thicknesses of various muscles among judo athletes of different performance levels. The subjects were 69 male judo athletes of 3 different performance levels. Group A was composed of athletes who participated in the Olympic Games or Asian Games (n = 13). Groups B (n = 21) and C (n = 35) were composed of judo athletes at a university who did or did not participate in intercollegiate competitions (including qualifying matches), respectively. Muscle and fat thicknesses were measured by B-mode ultrasound at 9 sites. Fat percentage was calculated from fat thicknesses using a previously reported equation. Fat-free mass was calculated from fat percentage and body weight. Muscles thicknesses were normalized to the height of the individual. Group A had significantly larger fat-free mass than Group C (p < 0.05). The normalized thicknesses of the elbow extensor and flexor muscles were significantly larger in Group A than in Group C. The normalized thickness of the elbow flexor muscle was significantly larger in Group A than in Group B. The results of this study showed that judo athletes with low performance levels such as those in Group C had lower fat-free mass, and the degree of development of the brachialis muscles differed according to performance level.

Influence of novel resin monomer on viability of L-929 mouse fibroblasts in vitro.

We have previously synthesized a novel acrylic resin monomer, methacryloyloxyethyl methyl succinate (TA). The aim of this in vitro study, therefore, was to examine its influence on cell viability using L-929 mouse fibroblasts and then compare the results with MMA, EMA, and LMA. Medium containing each monomer was changed every 15 minutes as some monomers were volatile. After one hour of exposure, these mediums were replaced with a normal medium and cells were further incubated for 72 hours. IC50 value for each monomer was determined, and chronological cell viability and cytomorphologic observation were evaluated. Viability was impaired in a dose-dependent manner. All monomers, except TA, tended to correlate between molecular weight and cell viability. On the other hand, TA showed excellent viability and did not impair growth abruptly. These results thus demonstrated that cellular damage by TA was much lower than that by other monomers.

Effects of scaling and root planing on the amounts of interleukin-1 and interleukin-1 receptor antagonist and the mRNA expression of interleukin-1beta in gingival crevicular fluid and gingival tissues.

OBJECTIVE: The purpose of this study was to evaluate the relationship between the clinical changes after non-surgical periodontal therapy and interleukin 1 (IL-1) in gingival crevicular fluid (GCF) and gingival tissues from patients with chronic periodontitis. BACKGROUND: The inflammatory responses mediated by IL-1 play an important role in periodontal tissue destruction. Although numerous studies have attempted to elucidate the dynamic movement involved in chronic periodontitis, the results have often conflicted. Such discrepancies may have been due to the inability to determine clinical disease activity. METHODS: Seven patients with chronic periodontitis were examined. The severity of periodontal inflammation was expressed using clinical parameters before and after a scaling and root planing (SRP) procedure. The amounts and concentrations of IL-1alpha, IL-1beta and IL-1 receptor antagonist in GCF were measured by enzyme-linked immunosorbent assay (ELISA) and IL-1 activity index was calculated. A needle biopsy in matching gingival tissues was also performed before and after the SRP procedure. The localization and mRNA expression of IL-1beta were determined using histological methods. RESULTS: Clinical parameters improved slightly after the SRP procedure. Only the probing pocket depth (PPD) was reduced significantly (p < 0.05). However, the amount of IL-1beta in GCF was slightly increased. The localization and mRNA expression of IL-1beta could still be observed after the SRP procedure. Therefore, none of the clinical parameters showed a high sensitivity or specificity for evaluating subgingival inflammation. CONCLUSION: These observations suggest that IL-1 is effective for evaluating in detail the state of subgingival inflammation.

The accuracy of volume estimates using ultrasound muscle thickness measurements in different muscle groups.

This study aimed to investigate the accuracy of estimating the volume of limb muscles (MV) using ultrasonographic muscle thickness (MT) measurements. The MT and MV of each of elbow flexors and extensors, knee extensors and ankle plantar flexors were determined from a single ultrasonographic image and multiple magnetic resonance imaging (MRI) scans, respectively, in 27 healthy men (23-40 years of age) who were allocated to validation ( n=14) and cross-validation groups ( n=13). In the validation group, simple and multiple regression equations using MT and a set of MT and limb length, respectively, as independent variables were derived to estimate the MV measured by MRI. However, only the multiple regression equations were cross-validated, and so the prediction equations with r(2) of 0.787-0.884 and the standard error of estimate of 22.1 cm(3) (7.3%) for the elbow flexors to 198.5 cm(3) (11.1%) for the knee extensors were developed using the pooled data. This approach did not induce significant systematic error in any muscle group, with no significant difference in the accuracy of estimating MV between muscle groups. In the multiple regression equations, the relative contribution of MT for predicting MV varied from 41.9% for the knee extensors to 70.4% for the elbow flexors. Thus, ultrasonographic MT measurement was a good predictor of MV when combined with limb length. For predicting MV, however, the unsuitability of a simple equation using MT only and the difference between muscle groups in the relative contribution of MT in multiple regression equations indicated a need for further research on the limb site selected and muscle analyzed for MT measurement.