Bonding effectiveness of different adhesion approaches to unground versus ground primary tooth enamel.

AIM: This study aims to evaluate the bonding effectiveness of self-etch and etch-and-rinse adhesive systems in on intact and ground primary tooth enamel. STUDY DESIGN: Sixty primary incisors were divided into 6 groups according to the adhesive system (etch-and-rinse - Adper Single Bond 2 - SB, 2 steps self-etch -Clearfil SE Bond - SE, and 1 step self-etch - One Up Bond F Plus OBF) and to the substrate (ground or intact enamel): G1-SB/intact enamel; G2-SE/intact enamel; G3- OBF/intact enamel; G4-SB/ground enamel; G5- SE/ground enamel and G6-OBF/ground enamel. METHODS: Microshear bond test specimens were prepared with microhybrid composite and after 24h of water storage the microshear test was performed. STATISTICS: Data were submitted to statistical analysis using two-way ANOVA and Tukey's tests (p<0.05). RESULTS: Comparing the enamel characteristics (ground or intact) only when SE was used a statistically significant difference was found, as G2 (21.12+/-4.52) was statistically lower than G5 (33.29+/-5.44). Among the intact enamel groups, SB (26.11+/-7.56) was statistically superior to SE (21.12+/-4.52) and OBF (17.01+/-3.96). However, when comparisons were made among groups of ground enamel, SE (33.29+/-5.44) was significantly higher than SB (26.35+/-8.18) and OBF (17.52+/-3.46). CONCLUSION: The two-step self-etch adhesive system is a reliable alternative to etch and rinse adhesive systems on both ground and intact primary enamel.

Stomach cancer-related mortality rate is higher in young Japanese women than in men.

This study compares stomach cancer-related mortality rates in Japan with those in European and Asian countries and analyzes trends in stomach cancer-related mortality rates according to gender in young Japanese over the period of 1957-1997. From official death certification numbers and population estimates, we obtained stomach cancer-related mortality rate for all ages and various ages according to gender. Japan's ranking compared to other countries in death percentage of all cancers which are attributable to stomach cancer was fourth for both men and women. In Japan and Ireland, total elimination of deaths from stomach cancer in men resulted in increased life expectancy of 0.68 and 0.22 y respectively, whereas the corresponding figures for women were 0.42 and 0.14 y respectively. The sex ratios of stomach cancer-related mortality rates were 0.75, 0.63, 0.80 and 0.94 for 25-29, 30-34, 35-39 and 40-44 y age groups, respectively, in 1997. The sex ratio of relative risk ranged from 0.62 to 0.92 in 25-40 y age groups during the observation period. The life expectancy in 30-34 y age group increased by 0.66 y for men and 0.41 y for women in 1995 after elimination of stomach cancer-related deaths. Our results suggest that stomach cancer-related mortality rates are still high in Japan and young women are at higher risk of stomach cancer-related death relative to young men and that sex ratio is stable or slightly decreased over the 40-y period. It is important to monitor this trend continuously in the next few years.

Stomach cancer-related mortality.

In Japan stomach cancer remains the leading cause of cancer-related mortality. We analysed the annual mortality rate of stomach cancer in relation to age, gender and life expectancy in Japan between 1970 and 1995. The adjusted stomach cancer-related mortality rates decreased from 88.9 in 1970 to 45.4 per 100,000 in 1995 in males and from 46.5 to 18.5 per 100,000 in females. The male-female ratio for stomach cancer-related mortality in all ages was 1.9-2.5 during this 25-year period, and the mortality rate was higher in females than in males at young age. The negative contribution to life expectancy for stomach cancer in males was 0.65 years and 0.42 years in females, which is consistent with a higher mortality rate in males. This negative contribution was 41.8% of total cancer in 1970 and 39.4% in 1995 in males and 34.4% and 16.0%, respectively, in females. Our results demonstrated the need to take into consideration the characteristics of stomach cancer in young women and the effects of ageing when designing programmes aimed at prevention and control of this malignancy.

Effect of distance and population size on patient trips in a prefecture of Japan: Application of a transportation distribution model to the demand for and supply of health services.

The gravity model, a method for analyzing transportation distribution in transportation engineering, was used to explain patient trips between ten health service regions in a Japanese prefecture. The OD (Origin-Destination) tables were constructed with zoning by regions, distinguishing between out- and inpatients. The observed trips were determined from the data of a survey conducted in 1992 that reported the locations of patient residences and chosen medical facilities.The base values used in the model calculations were the population size of each region and the road distance between the centers of regions. Problems of intrazonal trip were avoided by setting a mean intrazonal movement distance.This model was calibrated by the linear regression method with simultaneous validation by the index of correlation coefficients. The model was found to accurately simulate the effect of distance on the choice of medical facilities and the differences between the characteristics of in- and out-patients. The population value in use showed the relation not only with demand but also the supply of clinical services. It was suggested that the model presented here was useful in the allocation of medical resources and would help explain the relationship between suppliers and consumers of medical services.

Influence of different doses of methyl ethyl ketone on 2,5-hexanedione concentrations in the sciatic nerve, serum, and urine of rats.

Rats were injected subcutaneously with 2,5-hexanedione (2,5-HD 2.6 m mol/kg) alone (HD group) or with 2,5-HD and methyl ethyl ketone (MEK) (2.6 m mol/kg of each agent, HD&MEK group) or with 2,5-HD 2.6 m mol/kg and 5 times that dose (13.0 m mol/kg) of MEK (HD&5MEK group). The concentration of 2,5-HD in serum and in the sciatic nerve was determined 0.5, 1, 2, 4, 8, and 16 h after administration. Urinary 2,5-HD concentration was determined from the beginning of administration up to 16 h afterward. 1) The concentration of 2,5-HD in the serum, the sciatic nerve, and the urine was increased significantly (p < 0.05) in the co-administered groups; the higher the MEK doses were, the greater was the increase. 2) The clearance of 2,5-HD from both the serum and the sciatic nerve was delayed in the co-administered groups. The highest concentration in serum and the sciatic nerve appeared at 1 and 2 h respectively. After administration, the biological halflife (t1/2) of 2,5-HD from 1 to 8 h in serum was 6.5, 5.8 and 12.0 h for the HD, HD&MEK, and HD&5 MEK groups respectively. From 8 to 16 h, the t1/2 in serum was 1.2, 3.2 and 16.6 h for the HD, HD&MEK, and HD&5MEK groups, respectively. In nerve tissue, the prolongation of clearance in the co-administered groups was greater than that in serum, the t1/2 from 2 to 8 h being 5.2, 9.6 and 19.9 h for the HD, HD&MEK, and HD&5MEK groups, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

[Seroepidemiological study on hepatitis C virus infection in an endemic area of hepatitis C virus].

To clarify the prevalence of hepatitis C virus infection in a rural area with high incidence of chronic liver disease in Japan, sera from 412 inhabitants, aged 20-89 years, collected in 1989-1990 and sera from 483 inhabitants in the same area, collected in 1982 were tested for anti-HCV (antibody to C100-3) with the first-generation enzyme-linked-immunosorbent-assay (ELISA). In addition, sera from 118 inhabitants, aged 20-49 years, collected in 1989-1990 were tested for HCV-RNA with the polymerase chain reaction technique, with use of primers from the 5'-untranslated region of the HCV genome. Anti-HCV was positive in 175 out of 412 sera collected in 1989-1990 (42.5%): prevalence was higher in male (54.0%) than in female (34.9%). The prevalence rates in the 20-29, 30-39, 40-49, 50-59, 60-69, and 70-89 year-old group were 0%, 14.3%, 51.9%, 41.7%, 49.1%, and 53.1%, respectively. On the other hand, in sera collected in 1982, the overall prevalence of anti-HCV was 42.5% (175 of 412). The prevalence rates in the 20-29, 30-39, 40-49, 50-59, 60-69, and 70-89 year-old group were 12.5%, 43.3%, 51.5%, 50.3%, 60.7%, and 68.9%, respectively. The prevalence rate of young adults less than 40 years old in 1982 were higher than that in 1989-1990. In short, the prevalence of hepatitis C virus infection in this area had altered a great deal. HCV-RAN was detected in 42 of 118 (35.6%).(ABSTRACT TRUNCATED AT 250 WORDS)

Prediction of operative mortality based on impairment of host defense systems in patients with esophageal cancer.

To determine whether operative risk based on impaired defense systems can be predicted, we examined 21 markers in 32 patients with esophageal cancer seen between 1983 and 1985 and related them to postoperative deaths. A discriminant analysis proved useful in determining whether the patient would be at risk of operative mortality, based on impaired defense systems. This model, the host defense index (HDI), was then used clinically to evaluate findings in 64 patients seen between 1986 and 1991. During this period, a change in policy for performing transthoracic esophagectomy on and perioperative care for patients with impaired defense systems was associated with a decrease in operative mortality. Thus, the HDI is beneficial to predict the risk of operative mortality based on impaired defense systems in patients with esophageal cancer.

Factors related to malnutrition in patients with esophageal cancer.

Based on data indicating that decreases in body weight (BW), arm muscle circumference (AMC), and rapid-turnover proteins (RTPs) correlate with fatal septic complications after surgery for esophageal cancer, we examined possible factors contributing to protein-calorie malnutrition (PCM) in patients with this disease. Eight parameters of nutritional status were assessed. Associations between sex, age, stage of cancer, and degree of dysphagia and PCM were analyzed via multiple linear regression for 75 patients with esophageal cancer and 58 with gastric cancer. These four factors independently contributed to PCM in patients with esophageal cancer, whereas malignant tumor and age contributed to PCM in those with gastric cancer. The degree of dysphagia was related to decreases in serum albumin and RTP and weakly related to decreases in BW and AMC. Stage of cancer, age, and sex were associated with reductions in albumin and/or RTP. Thus, we conclude that simple starvation, malignant tumor, age, and sex contribute to PCM and probably to the occurrence of fatal septic complications postoperatively.

[Ion chromatographic determination of inorganic anions in human serum].

The ion chromatographic method is a rapid and reliable technique for the simultaneous determination of inorganic anion concentrations in serum. We are investigating the effects of various diseases on the serum levels of the following inorganic anions: phosphate, bromide, nitrate, and sulphate. In this paper, we tested the intra- and intermeasurement reproducibility of the ion chromatographic method using pooled normal human serum. We found a good intrameasurement reproducibility for all of the above inorganic anions. The intermeasurement reproducibility was good for three of the inorganic anions but not for nitrate. We measured the serum levels of these inorganic anions in 241 inhabitants in one rural area. Using sera of normal inhabitants chosen from the above group, we used the mean value plus or minus two standard deviations as the normal range of each inorganic anion. Our values are in agreement with previously published reports. We found that the serum levels of nitrate and sulphate tended to be increased in inhabitants with liver or kidney disfunction respectively.

[A study on the effect of water intake of umpires during a baseball game in a summer-heat environment].

The purpose of this study was to examine the effect of umpires' intake of water during a summertime baseball game, on serum and urinary biochemical elements, body weight and physiological factors. Twenty-eight umpires were classified into two groups. Group W was composed of 14 umpires who had water while those who did not were group C. Group W had 250 ml of water that was cooled to about 5 degrees C after the 5th inning of the game. The game was played in the following environment: atmosphere temperature was 31 degrees C; wet-bulb temperature was 26 degrees C; blackglove temperature was 40 degrees C; the velocity of the wind was 1.18 m/sec in bright sunshine on a hot and moist day. The results obtained were as follows. In group W, more body weight was lost than in group C, but statistically there was no significant difference. Urinary volume in group W became smaller than in group C, but statistically there was no significant difference. Water in blood increased in group W and decreased in group C but statistically there was significant difference. In both groups, oral temperature decreased, but only in group C was there a statistically significant difference. Although the intake of water increased the volume of perspiration, it did not dilute the concentrated blood, suppress the rise of body temperature, or result in a rise of low blood pressure.