A total of 22 Japanese patients with hypophosphatasia were included in a study analysing the relationship between mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) gene and the severity of the phenotyp...A total of 22 Japanese patients with hypophosphatasia were included in a study analysing the relationship between mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) gene and the severity of the phenotype in Japanese patients with hypophosphatasia. The enzymatic activity of some of the identified mutant TNSALP proteins was also examined using corresponding expression vectors. Eighteen mutations, including 6 novel ones, were identified in the patients. Among them,the common mutations were F310L and T1559del. Of note, five patients with F310L mutation in one of the alleles exhibited a relatively mild phenotype without respiratory complications despite its perinatal onset. In contrast, the T1559del mutation is associated with perinatal lethal and infantile forms when not found in patients with the F310L mutation. The genotype-phenotype relationship was, to some extent, consistent with the enzymatic activity of the mutant ALP proteins; mutations K207E and G409C found in a surviving case of infantile hypophosphatasia, as well as F310L, retained some residual activities, whereas T1559del caused a complete loss of activity. Conclusion: In Japanese patients, the common mutations F310L and T1559del are associated with the relatively mild and lethal forms of hypophosphatasia, respectively. Our results may enhance the importance of genotyping patients with hypophosphatasia to predict their prognosis.展开更多
The incidence and risk factors of nonalcoholic fatty liver disease (NAFLD) have never been prospectively determined. To determine the frequency and risk factors of NAFLD and chronological ordering between NAFLD, weigh...The incidence and risk factors of nonalcoholic fatty liver disease (NAFLD) have never been prospectively determined. To determine the frequency and risk factors of NAFLD and chronological ordering between NAFLD, weight gain, and features of insulin resistance, a historical cohort study was conducted in a Japanese workplace. A cohort free of previous liver injury, alcohol consumption of more than 140 g/wk, and hepatitis B or C infection (529 of 1,537 subjects), and a subcohort of 287 subjects free of insulin resistance-related features were identified. Elevated aminotransferases in nonalcoholics were used as a surrogate for NAFLD. High aminotransferases together with weight gain of more than 2 kg and insulin resistance-related features in the subcohort were sought for up to 5 years. The incidence of high aminotransferases was 31 per 1,000 personyears (71 events). A significant interaction occurred between age and sex in the development of high aminotransferases. In subjects younger than age 40 years, male sex (hazard ratio [HR]: 4.6), elevated body mass index (HR: 2.1), hypertension (HR: 2.6), and low high-density lipoprotein cholesterol (HR: 2.8) increased the risk of high aminotransferases, whereas age (HR: 0.6 for each 5 years) decreased the risk. In subjects older than age 40 years, glucose intolerance (HR: 5.3) was the only significant risk factor. In die subcohort, weight gain preceded high aminotransferases and other insulin resistancerelated features, which appeared sequentially in order of low high-density lipoprotein cholesterol, hypertriglyceridemia/hypertransaminasemia/hypertension, and glucose intolerance. In conclusion, this cohort study clearly showed chronological ordering and an association between development of elevated aminotransferases and risk factors of NAFLD.展开更多
文摘A total of 22 Japanese patients with hypophosphatasia were included in a study analysing the relationship between mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) gene and the severity of the phenotype in Japanese patients with hypophosphatasia. The enzymatic activity of some of the identified mutant TNSALP proteins was also examined using corresponding expression vectors. Eighteen mutations, including 6 novel ones, were identified in the patients. Among them,the common mutations were F310L and T1559del. Of note, five patients with F310L mutation in one of the alleles exhibited a relatively mild phenotype without respiratory complications despite its perinatal onset. In contrast, the T1559del mutation is associated with perinatal lethal and infantile forms when not found in patients with the F310L mutation. The genotype-phenotype relationship was, to some extent, consistent with the enzymatic activity of the mutant ALP proteins; mutations K207E and G409C found in a surviving case of infantile hypophosphatasia, as well as F310L, retained some residual activities, whereas T1559del caused a complete loss of activity. Conclusion: In Japanese patients, the common mutations F310L and T1559del are associated with the relatively mild and lethal forms of hypophosphatasia, respectively. Our results may enhance the importance of genotyping patients with hypophosphatasia to predict their prognosis.
文摘The incidence and risk factors of nonalcoholic fatty liver disease (NAFLD) have never been prospectively determined. To determine the frequency and risk factors of NAFLD and chronological ordering between NAFLD, weight gain, and features of insulin resistance, a historical cohort study was conducted in a Japanese workplace. A cohort free of previous liver injury, alcohol consumption of more than 140 g/wk, and hepatitis B or C infection (529 of 1,537 subjects), and a subcohort of 287 subjects free of insulin resistance-related features were identified. Elevated aminotransferases in nonalcoholics were used as a surrogate for NAFLD. High aminotransferases together with weight gain of more than 2 kg and insulin resistance-related features in the subcohort were sought for up to 5 years. The incidence of high aminotransferases was 31 per 1,000 personyears (71 events). A significant interaction occurred between age and sex in the development of high aminotransferases. In subjects younger than age 40 years, male sex (hazard ratio [HR]: 4.6), elevated body mass index (HR: 2.1), hypertension (HR: 2.6), and low high-density lipoprotein cholesterol (HR: 2.8) increased the risk of high aminotransferases, whereas age (HR: 0.6 for each 5 years) decreased the risk. In subjects older than age 40 years, glucose intolerance (HR: 5.3) was the only significant risk factor. In die subcohort, weight gain preceded high aminotransferases and other insulin resistancerelated features, which appeared sequentially in order of low high-density lipoprotein cholesterol, hypertriglyceridemia/hypertransaminasemia/hypertension, and glucose intolerance. In conclusion, this cohort study clearly showed chronological ordering and an association between development of elevated aminotransferases and risk factors of NAFLD.
