[Conditional logistic regression analysis of risk factors on congenital birth defects in Baotou]

Congenital defects are one of the common diseases in the newborns, and are important factors affecting the quality of the population. This survey was done to find risk factors related to congenital defects and to provide scientific basis for promoting birth quality. In this paper, a case-control study on 90 cases using 1:2 matching was carried out in Baotou area, and conditional logistic regression analysis showed that the following six major risk factors were associated with birth defects, i.e.: intake of certain drugs during pregnancy, exposure to radioactive rays, and contacting certain harmful chemical substances, common cold and fever during the period of pregnancy, smoking addiction of baby's father and the family history of certain defects of baby's parents.

A scanning electron microscopic study of the contraction of vascular wall cells in dog dental pulp

Ultrastructural changes in vascular wall cells in dog dental pulp after removal of connective tissue components were studied by scanning electron microscopy following administration of norepinephrine (0.2 mg/kg). Contracted smooth-muscle cells were frequently seen in arterioles of all sizes. The surfaces of these cells were highly irregular with numerous evaginations and invaginations, varying considerably in configuration and size. Many evaginations ran longitudinally or obliquely to the long axis of the vessel. Some meandering evaginations were also observed as, rarely, were small spherical or bulbous projections. Spidery smooth-muscle cells frequently seen in the tunica media of terminal arterioles and thought to be primitive smooth-muscle cells exhibited fewer irregularities than the typical spindle-shaped smooth-muscle cells beneath them. Pericytes in the larger post-capillary venules (20 microns or larger in diameter) often showed evaginations and invaginations, mainly running parallel to the vessel axis. On the other hand, no surface irregularities could be seen in pericytes of either the smaller post-capillary venules (less than 20 microns in diameter) or the capillaries, although occasional evaginations running parallel to the vessel axis were noted on the outer surface of the endothelium.

[Changes in levels of leucocytic estrogen receptor in patients with menopausal type II diabetes and its significance]

The number of estrogen receptors (ER) in human peripheral leucocytes in 12 women with menopausal type II diabetes was measured with radio-ligand binding method. The results were compared with those of 12 menopausal women without diabetes and 12 normal women of childbearing age. It was found that the number of ER in the patients was significantly decreased. Our data indicate that decrease of ER level in leukocytes may be related to the pathogenesis of type II diabetes in menopausal period.

[Changes in leucocytic estrogen receptor levels in patients with gynecomastia]

The number of estrogen receptor (ER) in human peripheral leucocytes in 13 men with gynecomastia were measured by radioligand binding method. The results were compared with those of 13 sex-and age-matched healthy subjects. It was found that the number of ER in leucocytes was significantly increased in gynecomastia (Rs of leucocytes were 1054 +/- 254 sites/cell). It suggested that increase of ER levels play an important role in the pathogenesis of gynecomastia.

[Effects of yin-tonics and yang-tonics on serum thyroid hormone levels and thyroid hormone receptors of hepatic cell nucleus in hyperthyroxinemic and hypothyroxinemic rats]

Hyperthyroxinemia model was made by giving thyroid tablet suspension to Wistar rats and hypothyroxinemia model was made by thyroidectomy. We measured serum thyroid hormone levels by RIA and the parameters of triiodothyronine receptors in rat hepatic cell nucleus by radio-ligand binding assay: Maximal binding capacity (Bmax) and Dissociation constant (Kd). It is found that (1) Yin-tonics can lower serum thyroid hormone levels and Bmax of hepatic nuclear T3R of hyperthyroxinemia rat from 167.14 +/- 25.62 fmol/100 micrograms DNA to 98.98 +/- 15.24 fmol/100 micrograms DNA, P less than 0.001. (2) Both Yang-tonics I and II can raise serum thyroid hormone levels of hypothyroxinemia rats, but not Bmax of hepatic nuclear T3R. Yang-tonics I even lowers Bmax. All the Chinese herbs have no effect on the Kd of rat hepatic nuclear T3R. The results may have some value in studying the effects of Chinese medical drugs.

[Inhibition of aldose reductase from rat lens by some Chinese herbs and their components]

Nearly 20 herbs or herbal components were screened for the inhibitory effect of rat lens aldose reductase(AR) with a fluorometric assay of AR activity. Among these Glycyrrhiza uralensis, Salvia miltiorrhiza, Radix astragali, Gentiana scabra, silybin, puerarin and baicalin were found to exhibit markedly inhibitory effects on AR comparable to Sorbinil. The authors suggest that some of the Chinese herbs used in the control of diabetic complications may act through the pharmacologic action of inhibiting AR.

Oral baicalin and liquid extract of licorice reduce sorbitol levels in red blood cell of diabetic rats

Intracellular accumulation of sorbitol, resulting from the increased glucose flux through polyol pathway with the action of aldose reductase, has been found pathogenic to chronic diabetic complications. It has been reported that baicalin and Glycyrrhiza uralensis Fisch can inhibit rat lens aldose reductase in vitro. In order to determine whether the said medicinal herbs give the inhibitive effect in vivo, 10 streptozotocin induced diabetic rats were treated with baicalin 150 mg/kg.d and liquid extract of licorice (LEL) 7.5 ml/kg.d for a week. RBC sorbitol was determined by a fluorometric assay before and after the treatment, as well as one week afterwards. It was found that oral baicalin and licorice dramatically reduced sorbitol levels in RBC without affecting blood glucose levels. The sorbitol levels was restored to its original values one week after discontinuing the treatment. The present study has demonstrated the effectiveness of baicalin and licorice in reducing RBC sorbitol levels in diabetic rats. Its mechanism is presumably through inhibition of aldose reductase. The feasibility of its clinical application for the control of diabetic complications is under investigation.

Tissue cryopreservation and rewarming study on giant cell tumor of bone

An attempt has been made of cryopreservation of tissue fragments from 6 GCTB surgical specimens. They have been kept in 10% DMSO or 15% glycerol medium and stored in liquid nitrogen for periods up to 180 days. Tumor cellular components survive the process of slow freezing and rapid thawing as cellular growth is successful in subsequent culture. Though certain reversible ultrastructural changes have been detected, no apparent distinction could be found in microscopic morphology, motility, growth behavior and LDH isozyme pattern between cultured cells of the cryopreserved fragments and those of the fresh ones. Electron microscopy shows that DMSO exceeds glycerol in protecting the ultrastructure of the cells. Slow cooling and rapid thawing is recommended because ice-crystals form in the intercellular space, which causes only light damage to the cells.