Search PubMed⌕ Search

Biomedical subjects

H Y Tang

Publications and source records attributed to H Y Tang.

30 records · Page 2Linked to original sources
PubMed1990

Hormone-free mouse glucocorticoid receptors overexpressed in Chinese hamster ovary cells are localized to the nucleus and are associated with both hsp70 and hsp90.

In this work, we examine the cellular localization and protein interactions of mouse glucocorticoid receptors that have been overexpressed in Chinese hamster ovary (CHO) cells (Hirst, M. A., Northrop, J. P., Danielsen, M., and Ringold, G. M. (1990) Mol. Endocrinol. 4, 162-170). We demonstrate that wild-type unliganded mouse glucocorticoid receptor, which is expressed in CHO cells to a level approximately 10 times that of L cells, is localized entirely to the nucleus by indirect immunofluorescence with the BuGR antireceptor monoclonal antibody. Overexpressed receptors that have either no hormone binding activity or no DNA binding activity because of point mutations also localize to the nucleus, providing genetic proof that the nuclear localization cannot reflect a steroid-mediated shift of the receptor from the cytoplasm to the nucleus and that DNA binding activity is not required for nuclear localization. Like unliganded progesterone receptors, which also associate in a loosely bound "docking" complex with the nucleus, the mouse glucocorticoid receptor overexpressed in CHO cells is associated with both hsp90 and hsp70. This is in contrast to the untransformed mouse glucocorticoid receptor in L cell cytosol, which is associated with hsp90 but not hsp70. The difference in hsp70 association between cell types could reflect overexpression of the receptor in CHO cells. However, like receptors in CHO cells selected for very high levels of overexpression, receptors in CHO cells selected for an intermediate level of receptor expression that is comparable to that of L cells are also bound to hsp70. This observation argues against an explanation of hsp70 association based purely on receptor overexpression, and we speculate that association of the unliganded glucocorticoid receptor with hsp70 might be a consequence of its nuclear localization in the CHO cells. Although there are differences between the mouse receptor in CHO cells and L cells, the nuclear localization signal of the untransformed mouse receptor reacts equivalently with the AP64 antibody against NL1 in cytosols prepared from both cell types.

Animals↗
PubMed1989

Efficacy of inactivated vaccine containing cyto-hemagglutinin against epidemic hemorrhagic fever in rabbits.

Using the Z-10 strain of epidemic hemorrhagic fever virus (EHFV) as seed, and the primary cell of Meriones unguiculatus kidney tissue as incubation cell, a propiolactone inactivated epidemic hemorrhagic fever (EHF) vaccine was prepared, according to a similar procedure required for the production of biological products such as the Japanese B encephalitis vaccine. Besides the EHFV antigen detected by ELISA or reversed passive hemagglutination test (RPHA) as were used for the formalin inactivated vaccine, higher titres (1:128-1:1024) of EHFV hemagglutinin antigen was also detected in this EHFV vaccine. Immunization with twice intramuscular injection of this vaccine produced high titred (1:20-1:160) neutralizing antibody and low titred (1:10-1:20) hemagglutination antibody, in addition to the immunofluorescence (IF) and reversed passive hemagglutination inhibition (RPHI) antibodies. These results indicated an apparent difference in the immunogenicity between the beta-propiolactone and formalin inactivated EHF vaccines. With the approval of the Ministry of Health, human test is now underway in this laboratory.

Animals↗
PubMed1987

Recent advances in microlymphatic surgery in China.

Development and advances in clinical and research work on limb lymphedema in China has progressed rapidly in recent years. The authors first performed successful lymphaticovenous anastomosis using the operating microscope for limb lymphedema in China in May, 1979. By 1983, surgery on 48 lymphedematous limbs in the authors' clinic had given good results in one-third of the cases. By the same year, 185 limbs with lymphedema were treated by lymphaticovenous anastomosis throughout China with excellent results achieved in 72.9% of the cases. Lymphology was investigated using animal models, intraluminal pressure, and venous graft substitution of lymphatics.

Animals↗
PubMed1985

Experimental observation of transplantation of vein graft to lymphatics.

We attempted to transplant a vein graft to normal lymphatics (LVL) to investigate whether it could survive and remain joined to the lymphatics as the environment changed. A total of 152 rabbits were divided into 3 groups. Group 1 was an LVL saline-irrigated group (n = 40), with a patency rate of 52.5%. Group 2 was an LVL nonirrigated group (n = 34), with a patency rate of 29.4%. Group 3 was an LV group (n = 78), with a patency rate of 32%. All specimens were examined under either light microscope or scanning electron microscope. The data indicated that an LVL anastomosis is practical and that preanastomotic irrigation can improve the patency rate. In both the LVL and the LV groups, endothelial regeneration, originating from the adjacent endothelium, commenced within 1 week after the anastomosis, with complete healing within 3 to 4 weeks. The vein graft tended to become "lymphaticized." Thrombosis was the main cause of obstruction. The patency rate can be increased by irrigation of the ends with saline before performing the anastomosis. The graft intima must be kept intact, the nutritive blood vessels of the lymphatics must be preserved, and the flow must be artificially increased soon after the anastomosis.

Animals↗