Biomedical subjects

Z B Wu

Publications and source records attributed to Z B Wu.

At least 19 recordsLinked to original sources

PubMed1992

[Role of mast cells in the development of liver fibrosis during experimental hepatocarcinogenesis in rats].

The role of mast cells (MC) in the development of liver fibrosis during experimental hepatocarcinogenesis in rats has been studied light microscopically, histochemically and electron microscopically. An increase in the number of MC in the proliferated connective tissue was found. The histochemical examination showed that the increased MC almost exclusively were connective tissue mast cells (CTMC), whilst mucosa mast cells (MMC) were only rarely seen. The electron microscopical observation revealed a close topographical relationship between MC and fibroblasts sending out pseudopodia, which encircled granula released from MC and phagocytized them. The fibroblasts with phagocytized MC granules were markedly activated showing enhanced formation of collagenous fibrils. Finally, the role of MC in the development of liver fibrosis is discussed.

Animals↗

PubMed1991

A consecutive ultrastructural study of action of homoharringtonine on fibroblasts in vitro.

The authors studied the effect of homoharringtonine (Hh), a semisynthetic Chinese herb, on the ultrastructure of in vitro cultured human conjunctival fibroblasts (HFb) and its mechanism of action. Preliminary results showed that the main characteristics of HFb damage caused by Hh were invagination of the nuclear membrane, aggregation and margination of chromatin, and massive vacuolization of the cytoplasm. In addition, Hh can inhibit the secretion of collagen fibers and the synthesis of microfilaments. Therefore, Hh might be an effective agent in the prevention and treatment of proliferative eye disorders.

Actin Cytoskeleton↗

PubMed1990

A highly efficient method for staining ultrathin sections.

A simple and efficient staining method to handle simultaneously thirty (or even more) electron microscope grids with ultrathin sections is described. The device applied is easily constructed from inexpensive and readily available materials but can bring easily high quality staining results, and the amount of stain and washing water required is very small.

Microscopy, Electron↗

PubMed1990

[Morphometric studies on the growth of bile canaliculi during liver regeneration in rats].

Morphometric analysis of the liver during regeneration after partial hepatectomy showed that the mean area and number of bile canaliculi increased, while the volume density of microvilli related to the lumina of the canaliculi decreased. These changes were observed 12 hours after the operation, which gradually returned to normal on the third day after operation. It indicated that the decrease of volume density of microvilli was the result of enlargement of bile canaliculi, which was different from the decrease of microvilli due to passive widening of the canaliculi such as in cholestasis from loss of microvilli. All these phenomena suggest that enlargement of the area of bile canaliculi during liver regeneration may be due to the increase of membranous protein synthesis. Moreover, the increase of the number of bile canaliculi suggests that the proliferation of hepatocytes is associated with formation of new branches of bile canaliculi.

Animals↗

PubMed1990

[The effect and mechanism of estrogen on hepatocyte regeneration in rats].

Liver regeneration model following partial hepatectomy was used to study the effect and mechanism of estrogen on hepatocyte regeneration of rats. Each animal in the experimental groups received a single injection of diethylstilbestrol (DES) subcutaneously. Results showed that estrogen had a remarkable promoting effect on hepatocyte regeneration. Both 3H-TdR labelling and mitosis indices of hepatocytes in the experimental groups increased markedly. In DES-treated rats, synthesis of estrogen receptor of hepatocyte increased gradually and the translocation of ER from cytoplasm to nucleus was also enhanced at the same time, indicating that the mechanism of DES on hepatocyte regeneration consisted promoting of the interaction of ER and nucleus. There was no statistically significant difference (P greater than 0.05) found in the number of Kupffer cells between all the experimental and their corresponding control groups. But in ultrastructure, Kupffer cells of animals in the experimental groups presented increase of cell size with abundant cytoplasm; longer and more pseudopodia as well as phagolysosomes, suggesting that DES could activate Kupffer cell and promote its function. The relationship between Kupffer cells and liver regeneration is discussed.

Animals↗

PubMed1989

Light and electron microscopic detection of lectin binding sites in normal and disordered human gastric tissues.

Lectins are now widely used as histochemical markers and probes for carbohydrate structures in glycoproteins. In the present study, a method is described for the light and electron microscopic detection of Ulex europaeus agglutinin I binding sites in the normal and neoplastic tissues. The results showed that the gastric mucus-producing cells and some vascular endothelial cells could be strongly stained with labelled lectin in normal mucous membrane. The positive staining reactivity was reduced greatly in neoplastic tissue either in paraffin sections or in thin sections. This suggested that the secretions of gastric carcinoma are different from those of normal gastric mucosa and represent differentiation of neoplastic cells to some degree.

Adenocarcinoma↗

PubMed1989

Immunohistochemical localization of vascular endothelial cell factor VIII/von Willebrand factor antigen in human normal and disordered gastric tissues.

Vascular endothelial cell factor VIII/von Willebrand factor antigen (FVIII/vWF Ag) of normal and disordered gastric tissues was studied with staphylococcus protein A-gold (PAG) labelling followed by photochemical silver reaction. FVIII/vWF Ag was localized clearly in the tissue fixed with various common fixatives and embedded in paraffin without enzyme treatment. The most satisfactory staining and the least nonspecific background were observed in the tissues fixed with Zamboni's and Bouin's solutions. The staining reaction could be enhanced, if the sections were pretreated with trypsin and subtilisin. Under the electron microscope, the gold particles were found over the Weibel-Palade bodies of vascular endothelial cells in the tissues fixed either in Zamboni's solution or in Zamboni's solution-osmium tetroxide, and embedded either with Lowicryl K4M or with Epon 812. It has been proved to be a better technique in investigation of FVIII/vWF Ag in vascular endothelial cells.

Adenocarcinoma↗

PubMed1988