Takashi Akamatsu

Green Tea Consumption and Serum Lipids and Lipoproteins in a Population of Healthy Workers in Japan

PURPOSE To examine the relation between green tea consumption and serum lipids and lipoproteins. METHODS The subjects were 13,916 workers (8476 men and 5440 women) aged 40-69 years at over 1000 workplaces in Nagano prefecture, central Japan. They underwent health screening offered by a single medical institute between April 1995 and March 1996 and did not have morbid conditions affecting serum cholesterol levels. Serum concentrations of total cholesterol, high-density lipoprotein (HDL) cholesterol and triglycerides were measured at the screening. The consumption of green tea and other life-style characteristics were ascertained by a questionnaire. The data were analyzed with multivariate linear model. RESULTS Daily consumption of green tea was reported by 86.7% of subjects. Green tea consumption was, statistically, significantly associated with lower levels of serum total cholesterol in both men and women while its associations with serum triglycerides and HDL cholesterol were not statistically significant. The inverse association of serum total cholesterol with green tea consumption appeared to level off at the consumption of more than 10 cups/day. Excluding the outlying subjects drinking more than 10 cups/day (0.4%), the regression analysis adjusting for age, body mass index, ethanol intake, smoking habit, coffee intake, and type of work showed that daily consumption of one cup of green tea was associated with a reduction in serum total cholesterol by 0.015 mmol/L (95% confidence interval 0.006 to 0.024, p < 0.001) in men and 0.015 mmol/L (0.004 to 0.025, p < 0.01) in women. After additional adjustment for selected dietary factors, the inverse association remained statistically significant; one cup of green tea per day was associated with a reduction in serum total cholesterol by 0.010 mmol/L (0.001 to 0.019, p = 0.03) in men and 0.012 mmol/L (0.001 to 0.022, p = 0.03) in women. CONCLUSION Consumption of green tea was associated with lower serum concentration of total cholesterol in Japanese healthy workers age 40-69 years; however, green tea consumption was unrelated to serum HDL-cholesterol and triglycerides.

Ultrastructure of the foregut and associated glands in the lung fluke, Paragonimus miyazakii (Digenea: Troglotrematidae), with particular reference to their functional roles

The foregut and associated glands of a digenetic trematode, Paragonimus miyazakii, were examined in the forebody by transmission and scanning electron microscopy as well as by light microscopy, and their functional roles were discussed. The foregut is lined with a general tegument without spines and sensory receptors throughout its length, although it consists of the mouth, pharynx, and esophagus. This foregut tegument is regionally and intraregionally modified in appearance, suggesting the performance of auxiliary functions in digestion. This appearance is characterized by long, frequent cytoplasmic extensions of the apical tegument around the middle portion of the mouth and the anterior esophagus. Electron‐dense granules and multimembranous and multilamellar bodies are developed in the tegument to various degrees, and elaborately in the apical layer of the prepharynx. A single type of unicellular gland is embedded in the antero‐middle part of the worm in small groups. The gland cells synthesize clear secretory granules as a chief product, each granule with a pleomorphic, dense, core‐like inclusion. Mature granules are elliptical in shape, approximately 500 nm in diameter, and are subsequently discharged into the prepharyngeal foregut lumen after passing through the elongated cytoplasm of the gland cell. In the prepharynx and pharynx, host blood cells are apparently processed for digestion. In the wide lumen of the esophagus, foodstuff could undergo sufficient digestion prior to absorption by the cecal epithelium. J. Morphol. 237:43–52, 1998.

Ultrastructure of the ootype of the lung fluke Paragonimus ohirai (Digenea, Troglotrematidae) in mated and single-infection worms.

The ootype ofParagonimus ohirai was studied by both scanning and transmission electron microscopy. The ootype wall in 20-week-old worms from single infections was similar in its epithelial cell architecture and components to that of mated worms at 10 weeks postinfection. The lining epithelium consisted of a single layer of nucleated cells. The cytoplasm displayed a variety of organelles such as occasional Golgi complexes, well-developed annulate lamellae, frequent lysosomes, abundant mitochondria, and numerous ribosomes, suggesting high activities of intracellular synthesis and digestion. The former three organelles were generally located in the apical cytoplasm protruding into the lumen and may be significant in participating in regulation of egg formation. The present comparative studies suggest that the ootype epithelium can mature even by single infections and that the organized intracellular activities remain developed in single worms even after prolonged infection.