A nephritogenic antigen for acute poststreptococcal glomerulonephritis (APSGN) was isolated recently from group A streptococcus and termed nephritis-associated plasmin receptor (NAPlr). In vitro experimental data indicate that the pathogenic role of NAPlr occurs through its ability to bind to plasmin and maintain its proteolytic activity. However, the mechanism whereby this antigen induces glomerular damage in vivo has not been fully elucidated. Renal biopsy tissues from 17 patients with APSGN, 8 patients with rapidly progressive glomerulonephritis, and 10 normal kidneys were analyzed in this study. Plasmin-like activity was assessed on cryostat sections by in situ zymography with a plasmin-sensitive synthetic substrate. Serial sections were simultaneously assessed for NAPlr deposition by immunofluorescence staining. Glomerular plasmin-like activity was absent or weak in normal controls and in patients with rapidly progressive glomerulonephritis, although tubulointerstitial activity was occasionally detected. Prominent glomerular plasmin-like activity was found in patients who had APSGN and in whom glomerular NAPlr was positive, whereas it was absent or weak in patients who had APSGN and in whom glomerular NAPlr was negative. The distribution of glomerular plasmin-like activity was identical to that of NAPlr deposition but was generally different from that of fibrin(ogen) deposition as assessed by double staining. The activity was abolished by the addition of aprotinin to the reaction mixture but was not altered by the addition of a matrix metalloprotease inhibitor, a cysteine protease inhibitor, or inhibitors of plasminogen activators. Thus, upregulated glomerular plasmin-like activity in relation to NAPlr deposition in APSGN was identified. This result supports the nephritogenic character of NAPlr and offers insight into the mechanism whereby this antigen induces nephritis.

Cell electrophoretic mobility (EPM) can be used to characterize individual cells. The purpose of this study is to establish reproducible and reliable cell EPM values obtained using microcapillary electrophoresis (microCE) chips. We studied cell electrophoresis on microCE chips through the comprehensive measurement of EPM and zeta potential. The inner wall of microchannels in microCE chips was coated with three kinds of reagents, namely bovine serum albumin (BSA), gelatin, and 2-methacryloyloxyethylphosphorylcholine (MPC) polymer to prevent nonspecific adhesion and interaction between cells and the inner wall. Electrophoresis was conducted in phosphate-buffered saline (pH 4-9) using erythrocytes extracted from sheep whole blood. Electroosmotic flow (EOF) mobility was measured using noncharged particles, and then the true EPM was calculated by subtracting the EOF mobility from the electromigration. MPC polymer coatings in microCE chips reduced the zeta potential of the inner wall and fully prevented nonspecific adhesion. EPM data obtained using microCE chips were almost the same and reproducible over a wide range of pH irrespective of the coating reagent used. In conclusion, reliability in the measurement of cell EPM using microCE chips was realized.

The profibrotic effect of plasminogen activator inhibitor-1 (PAI-1) in renal fibrosis is widely recognized, but its mechanism remains controversial especially in chronic progressive kidney disease. In the present study, pioglitazone (Pio) and candesartan (CD), which are reported to inhibit PAI-1, were administered to spontaneously hypercholesterolemic (SHC) rats, a model of chronic progressive kidney disease. Therapeutic effects and effects on the intrarenal plasmin cascade were examined. Eight-wk-old SHC rats were used as controls. Oral administration of vehicle alone, Pio, or CD was performed starting at 8 wk of age and was continued for 24 wk. The degree of renal fibrosis was evaluated by sirius red staining of kidney sections and by total collagen assay of renal homogenates. The renal PAI-1 protein level was assessed by Western blotting, and plasmin activity was analyzed by chromogenic assay and casein gel zymography. Urinary protein and blood urea nitrogen were significantly increased in the vehicle-treated group, but the increase was attenuated in the Pio- and CD-treated groups. This correlated well with the degree of fibrosis as assessed by sirius red staining and total collagen assay. The PAI-1 protein level was also increased significantly in the vehicle-treated group, and the increase was attenuated in the Pio- and CD-treated groups. Despite the presumed plasmin-inhibitory function of PAI-1, plasmin activity changed in parallel with PAI-1. These results suggest that Pio and CD inhibit PAI-1 and exert renoprotective effects against chronic progressive renal disease, but its action is independent of the regulatory function on plasmin activity.

Twin and family studies had shown that genetic factors are important determinants of bone mass. Multiple genes might be involved. One candidate gene, the reversion-induced LIM gene (RIL), is a PDZ and LIMdomain-containing protein and has been localized within the cytokine cluster of chromosome 5 (5q31.1). In a genetic study of 370 adult Japanese women, we investigated the correlation between radial bone mineral density (BMD) and a genetic variation ()3333T fi C) of the 5'-flanking region of RIL gene. A significant association was identified between the RIL variation )3333T fi C and radial BMD (r=0.15, P=0.003). The variation of the RIL locus may be an important determinant of osteoporosis.Keywords Single-nucleotide polymorphism AE RIL AE Bone mineral density AE Association study IntroductionOsteoporosis is a multi-factorial common disease that is characterized by reduced bone mass and increasing risk of fracture. Genetic and environmental factors play important roles in the determination of bone mineral density (BMD) (Hirota et al. 1992;Suleiman et al. 1997;Pocock et al. 1987;Krall and Dawson-Hughes 1993).Previous studies have examined associations of candidate gene polymorphisms with BMD. Examples are the genes encoding the vitamin D receptor, the estrogen receptor, the apolipoprotein E and type I collagen, combinations of which may determine individual BMD levels (Morrison et al. 1994;Melhus et al. 1994;Greenfield and Goldberg 1997;Kobayashi et al. 1996;Shiraki et al. 1997;Uitterlinden et al. 1998). In addition to these makers, numbers of unidentified polymorphic genes may participate in determining the bone mass of an individual. Candidates might be genes involved in cytokine-signaling pathways, the hormonal regulation of calcium balance and bone mineral, or the cellular function of bone cells.One possible candidate gene localized within the cytokine cluster of chromosome 5 (5q31.1) is the reversion-induced LIM gene (RIL), whose mRNA expression in human bone marrow stromal cells has been strongly detected in a previous study (Bashirova et al. 1998). Although its exact function is not defined as yet, an involvement of osteoblast development/function is implicated.In this study, we have carried out a correlation study of genetic variations in RIL gene for radial BMD levels. Involvement of an RIL gene polymorphism was tested with respect to the regulation of BMD. Subjects and methodsSubjects DNA samples were obtained from peripheral blood of 370 adult Japanese women (Shinohara et al. 2001). BMD was measured in all of these subjects. Mean ages and body mass indices (BMI) with standard deviations (SD) were 58.4±8.6 years (range:

In this cross-sectional study, we investigated the effect of daily walking steps on ultrasound parameters of the calcaneus in elderly Japanese women. The subjects were 143 community-dwelling elderly women aged 61-87 years (mean age 71.4+/-5.5 years). The speed of sound (SOS), broadband ultrasound attenuation (BUA) and the stiffness index (Stiffness) of the calcaneus were measured. Walking steps were recorded using a pedometer for 7 consecutive days as an outcome measure of physical activity. In univariate analyses, steps/day significantly decreased with aging. SOS, BUA and Stiffness showed negative correlations with age and positive correlations with weight. Linear relationships were not seen between any of the ultrasound parameters and daily walking steps. Then, the ultrasound parameters were adjusted for age and/or weight using multiple regression models, and the relationships between the adjusted ultrasound measurements and walking steps were examined using quadratic regression models. Walking activity up to approximately 12,000 steps/day was positively associated with the adjusted ultrasound measurements, above which additional walking steps had no positive effect. We conclude that daily walking steps may be suitable for evaluating the relationship between ultrasound parameters and physical activity in elderly women, but further research is needed to confirm the effect of daily walking steps on the rate of bone loss.

We investigated the relation between the vitamin D receptor (VDR) genotype and bone mass including the effect of exercise history as a measure of physical activity. BUA (broadband ultrasound attenuation), SOS (speed of sound) and Stiffness index of the calcaneus were measured using an ultrasound bone densitometer in 105 Japanese young adult women (age: mean+/-SD 20.4+/-4.1 years, ranged 18-37) by the calcaneal ultra sound measurement to assess bone mass. Physical activity was measured using a questionnaire about exercise and was calculated as exercise hours per week during prepuberty (elementary school), puberty (junior and senior high school) and a current period (from >18 years old). VDR genotype was determined by the BsmI restriction site of the VDR gene. Significant differences were observed in age-adjusted and menarche age-adjusted SOS and Stiffness between BsmI VDR genotypes. We also examined the interaction between VDR genotype and the amount of exercise. The association between ultrasound parameters and exercise hours per week was evaluated with simple regression analysis according to VDR genotype. There was a significant difference in the slope between VDR genotypes in regression analysis of exercise hours per week during senior high school for SOS (P<0.05). Furthermore, we conducted multiple regression analysis to examine the contribution of each factor to ultrasound parameters. VDR genotype was a significant independent variable for SOS (P<0.05). Exercise hours each week during senior high school was a significant independent variable for all ultrasound parameters (all: P<0.001). In conclusion, there was a partial significant relation between VDR genotype and ultrasound parameters, but the exercise hours each week during senior high school was the strongest independent factor for bone mass in young adult Japanese women.

Smoking habits are thought to be strongly impacted by family relationships. In this study, we looked specifically at family relationships with the aim of finding effective anti-smoking education measures. We surveyed 290 university students in order to establish their current smoking habits, along with their family relationships from primary and junior high school until now. The results showed that students with one or more smokers in their family were clearly more likely to smoke. Furthermore, a poor relationship between the student's parents and a poor relationship with his/her father are believed to have a causal relationship with the student smoking. In the section in which students were asked how often they were told to study, we found that students who smoked had been instructed to study a significantly higher number of times. It is believed that the stress experienced by students frequently told that they must study during their elementary or junior high school years leads to a tendency to smoke. Among the group of non-smokers, we found many who ate breakfast with their parents during elementary or junior high school, along with many who regularly went on holidays with their families. The lack of these things appears to distance parents from children and may be a factor regarding why children end up smoking. In this study, while no clear correlation was found between family relationships and smoking, several types of family relationships that may lead to smoking were suggested.

This survey was conducted with the aim of clarifying and providing guidance regarding correct lifestyle and exercise habits from adolescence in order to prevent the development of osteoporosis. The subjects included 195 Japanese adult females. We measured their calcaneal bone density by ultrasonography, the index of which was determined as SOS (Speed of Sound). We examined their physical characteristics, health conditions, amount of physical activity, exercise history, and eating habits, and then analyzed the relationship thereof with bone density. No significant correlation was found between height, weight, BMI (Body Mass Index), or body fat percentage and the SOS value. Moreover, the bone density among those with a history of exercise was high. Breaking it down, we obtained results such as the fact that exercise habits during the junior and senior high school years had a great impact on the acquisition of peak bone mass, although no relationship between exercise habits and bone density was found during the elementary school years. Furthermore, as the bone density of students who continued exercising in junior and senior high school indicated high values, continuity of exercise during the growth period (during puberty) is believed to have a great impact on peak bone mass. Upon investigating the content of meals including foods which have a positive impact on the bones, "bean and bean products" and "green and yellow vegetables" were found to be related to bone density. From the above, the effect that the lifestyle of young adult females had on bone density was partially clarified. In particular, one factor which had a strong relationship with current bone density was exercise history during the junior and senior high school periods. It was clarified that continuously engaging in exercise and placing strain on the bones during these periods lead to high bone density acquisition.