[Pathogenesis of liver fibrosis in patients with chronic hepatitis B].

OBJECTIVE: To explore the role of sinusoidal endothelial cell in the development of liver fibrosis, and to dissect the relationship among hepatic microcirculation disorders, hepatic sinusoidal capilarization and liver fibrosis. METHODS: Liver biopsy was performed in fifty-six patients with chronic hepatitis B. The liver tissues were observed under light microscope and transmitted electronic microscope. RESULTS: Of 56 cases, 39 cases were mild hepatitis, 10 were moderate hepatitis, and 7 were severe hepatitis. The morphology of hepatic stellate cells (HSCs) was similar to that of fibroblasts in the tissues of the patients with chronic hepatitis B. Collagenous fibers were deposited around the hepatic stellate cells. Electron-dense materials were deposited between sinusoidal endothelial cell and hepatic stellate cell. The size and amount of fenestraes of sinusoidal endothelial cells were reduced in 53 of 56 cases. The consecutive or inconsecutive membrane-like materials were observed along sinusoidal endothelial cells in 20 cases. Collagen fibers were observed in the space of Disse in 15 cases. Even in the patients with normal hepatic functions, red blood cells aggregation and microthrombi could be observed in the liver tissues. CONCLUSION: Sinusoidal endothelial cells are involved in development of liver fibrosis by interacting with hepatic stellate cells. Hepatic microcirculation disorders and sinusoidal capillarization are important changes in the early stage of liver fibrosis.

[Effects of flashing light on ocular growth and development of myopia in pigmented guinea pigs].

OBJECTIVE: To investigate the effects of flashing light exposure on ocular growth and development of myopia in guinea pigs. METHODS: Thirty 4-week-old pigmented guinea pigs were randomly divided into three groups. Animals in group I were reared with the flashing light continuously and lasted for 6 weeks. The flashing frequency was 15 times per minutes and every flash includes 2 seconds light on and 2 seconds dark. Animals in group II and III were reared with normal light on, and the illumination cycle was 12 hours light/12 hours dark in group II and 24 hours light in group III. After 6 weeks, the effects of flashing light on eye development were assessed by cycloplegic retinoscopy, a-scan ultrasonography and eye weight. The histopathology changes of sclera, choroids and retina in posterior pore of the eye were examined using light microscope and transmission electron microscope. RESULTS: At the end of the treatment period, guinea pigs reared in flashing light exhibited -7.00 D myopia, eye axial elongated 0.56 microm, and the weight increased 68 mg. The histopathology examination showed that the posterior sclera fibroblast become more active, the cell number increased, and the place between fibers became larger, the posterior choroids became thinned, and the outer membrane of photoreceptor cells became shorter and irregular, when compared with the control groups. CONCLUSION: Flashing light can promote ocular growth and induce myopia in pigmented guinea pigs.