Bovine thecal cells secrete factor(s) that promote granulosa cell proliferation

To determine if soluble factors (other than steroids) secreted by bovine thecal cells may be involved in local regulation of follicular development, we examined the effects of thecal cell secretory products on the growth of granulosa cells obtained from the same follicles. DNA synthesis (assessed by the incorporation of 3H-thymidine) by granulosa cells plated on coverslips and cocultured with, but not directly in contact with, thecal cells in organ culture dishes in a serum-free medium was 5-fold greater than controls. The effect of the thecal cell-secreted products on DNA synthesis by granulosa cells was significantly higher than the maximum response produced by epidermal growth factor (EGF). Thecal cell-conditioned medium stimulated 3H-thymidine incorporation into the DNA of granulosa cells and a normal rat kidney cell line in a dose-dependent manner. The increases in 3H-thymidine incorporation into granulosa cell DNA subsequently lead to an increase in cell number. Preliminary characterization studies using ultrafiltration membranes indicated that the mitogenic factor was retained in the greater than 10,000 molecular weight fraction. The activity was stable to heating at 90 degrees C for 5 min and was not extracted in ether. The thecal cell-generated growth factor may act as a paracrine regulator of granulosa cell growth, thus providing the dominant follicle with autonomy over other follicles in the cohort.     

False positive reaction for carcinoembryonic antigen in paget cells

Virchows Archiv B Cell Pathology - Paget cells from cases of mammary and extramammary Paget’s disease were examined for carcinoembryonic antigen (CEA) and CEA-related antigens by the...     

Immunohistochemical characteristics of the constituents of senile plaques and amyloid angiopathy in aged cynomolgus monkeys

Abstract: In this study, we immunohistochemically examined the several constituents of senile plaques (SPs) and cerebral amyloid angiopathy (CAA) in aged cynomolgus monkeys. Apolipoprotein E (apoE) deposited in all mature plaques and CAA, and in half of the diffuse plaques. Alpha-1-antichymotripsin (αACT) deposited in half of the mature plaques and in one third of the CAA. Amyloid precursor protein (APP), ubiquitin (Ub), and microtubule-associated protein-2 (MAP-2) accumulated in the swollen neurites of mature plaques. Glial fibrillary acidic protein (GFAP) was detected in the astrocytes and their processes surrounding the mature plaques. Tau was detected in neither the SPs nor CAA. Therefore, mature plaques involved extracellular Aβ, apoE, and αACT, and also astrocytes and swollen neurites. However, diffuse plaques involved only extracellular Aβ and apoE. Since these features, except for tau, were consistent with those in humans, this animal model will be useful for studying the pathogenesis of cerebral amyloid deposition.     

Structure of the Gene for an Auxin-Binding Protein and a Gene for 7SL RNA from Arabidopsis thaliana

A genomic clone encoding an auxin-binding protein (ABP) fromthe endoplasmic reticulum was isolated from Arabidopsis thaliana.The ABP gene consisted of 5 exons and 4 introns and encodeda polypeptide of 198 residues. A gene encoding the 7SL RNA ofthe signal recognition particle was located downstream of theABP gene. ⁴Recipient of a scholarship from the National Education Commission,People's Republic of China.     

Kinetic Properties of Bovine Pineal Tryptophan-5-Monooxygenase Activated by an Endogenous Activating Substance

Abstract: We previously reported that an endogenous activating substance different from bovine serum albumin, phospholipids and heparin, exists in the extract from bovine pineal glands and that this substance interacts with tryptophan-5-monooxygenase under reducing conditions with sulfhydryl reagents, to stimulate monooxygenase activity. The present paper reports that the activating substance is of peptide nature; that it is sensitive to trypsin-digestion; and that it does not change the apparent K _m's for substrates, L-tryptophan and oxygen, and coenzyme, reduced biopterin or DMPH₄: but that it increases the V _max 1.5- to 2.3-fold. These results suggest that an activating protein, present in some particles of the cell structure, activates tryptophan-5-monooxygenase under the regulation of a sulfhydryl compound. The apparent K _m's for reduced biopterin and DMPH₄ were 77.2μM and 294 μM, respectively. The apparent K _m's for L-tryptophan and oxygen with reduced biopterin were 15.0 μM and 4.7%, respectively: with DMPH₄, they were 11.0 μM and 8.5%, respectively. Significant inhibition of both L-tryptophan and oxygen was observed with reduced biopterin, but not with DMPH₄ (at the tested concentrations of up to 0.5 MM and 20%, respectively).     

ABCG2 expression and uric acid metabolism of the intestine in hyperuricemia model rat

Abstract

To elucidate roles of the intestine in uric acid (UA) metabolism, we examined ABCG2 expression, tissue UA content and xanthine oxidoreductase (XOR) activity in different intestinal segments. Male SD rats were assigned to control group or oxonic acid-induced hyperuricemia (HUA) group. In control rats, ABCG2 was present both in villi and crypts in each segment. Tissue UA content and XOR activity were relatively high in duodenum and jejunum. However, in HUA rats, tissue UA content was significantly elevated in the ileum, whereas it remained unaltered in other segments. Moreover, ABCG2 expression in the HUA group was upregulated both in the villi and crypts of the ileum. These data indicate that the ileum may play an important role in the extra-renal UA excretion.