Pluripotent embryonic stem cells hold a great promise as an unlimited source of tissue for treatment of chronic diseases such as Type 1 diabetes. Herein, we describe a protocol using all-trans-retinoic acid, basic fibroblast growth factor and dibutyryl cAMP (DBcAMP) in the absence of embryoid body formation, for differentiation of murine embryonic stem cells into definitive endoderm that may se...

The effects of DDT compounds on the function and viability of interrenal corticosteroidogenic tissue were investigated in vitro in rainbow trout (Oncorhynchus mykiss) in a dose–response study. The o,p9-dichlorodiphenyldichloroethane (DDD) was the most potent of the tested chemicals in decreasing adrenocorticotropic hormone (ACTH)-stimulated cortisol secretion by head kidney fragments compared w...

The prothoracic glands of early last (fifth) instar larvae of the silkworm are inactive with regard to ecdysteroidogenesis and unresponsive to prothoracicotropic hormone (PTTH) [J. Insect Physiol. 31 (1985) 455]. In an attempt to elucidate the hormonal mechanisms that cause the inactivity, we compared the effects of PTTH, dibutyryl cyclic AMP (dbcAMP), a cAMP phosphodiesterase inhibitor (IBMX),...

The embryonal carcinoma PCC4uva differentiates into neurons in response to treatment with retinoic acid and dbcAMP. We used this in vitro model system to study the effects of laminin on early neural differentiation. Laminin substrata markedly potentiate neural differentiation of retinoic acid and dbcAMP-treated cultures. Only laminin induced more rapid neural cell body clustering, neurite growt...

Endometriosis is a poorly understood gynaecologic disorder that is associated with infertility. In this study, we examined the expression of HOXA10 in the eutopic endometrium of baboons with induced endometriosis. A decrease in HOXA10 mRNA was observed after 3, 6, 12 and 16 months of disease, which reached statistical significance at 12 and 16 months. HOXA10 protein levels were decreased in bot...

Postinjury deficits in monocyte tumor necrosis factor receptors (moTNFR) activity may alter beneficial functions during an inflammatory response. Several counter-regulatory hormones elicited during inflammation may modulate tumor necrosis factor (TNF) activity, but little is known about their influence on moTNFR. Also, catecholamines inhibit TNF production, but the adrenoreceptor mechanism of t...

The regulation of the interleukin-4 receptor (IL-4R) was studied at mRNA and protein level in monocytic cells on stimulation with activators of different intracellular signaling pathways and IL-4. Activation of protein kinase C-dependent pathways with phorbol myristate acetate (PMA) or activation of protein kinase A-dependent pathways with DBcAMP and prostaglandin E2 resulted in an augmented IL...

Elevated serum glucocorticoid levels contribute to the progression of many diseases, including depression, Alzheimer's disease, hypertension, and acquired immunodeficiency syndrome. Here we show that the benzamide derivative N-[2-(4-cyclopropanecarbonyl-3-methyl-piperazin-1-yl)-1-(tert-butyl-1H-indol-3-yl-methyl)-2-oxo-ethyl]-4-nitrobenzamide (SP-10) inhibits dibutyryl cyclic AMP (dbcAMP)-induc...

In this study, we investigated the mechanisms responsible for the growth-inhibitory action of parathyroid hormone-related protein (PTHRP) in A10 vascular smooth muscle cells (VSMC). Fluorescence-activated cell sorting analysis of serum-stimulated VSMC treated with PTHRP or dibutyryl-cAMP (DBcAMP) demonstrated an enrichment of cells in G1 and a reduction in the S phase. Measurement of DNA synthe...

To study the role of extracellular nucleosides and nucleotides in the regulation of Sertoli cells, the effects of agonists which occupy A1 and P2 purinergic receptors on aromatase and gamma-glutamyl transpeptidase (gamma-GTP) activities and on transferrin secretion were tested. Sertoli cell treatment with purinergic agonists for a prolonged period of time (72 h) resulted in an increase in aroma...