Calcyclin and calvasculin exist in human platelets.

Using Ca(2+)-dependent affinity chromatography on a synthetic compound (W-7)-coupled Sepharose column, three distinct Ca(2+)-binding proteins have been identified in human platelets. The molecular mass of these three distinct proteins was estimated to be 10, 10.5, 17 kDa, respectively, by polyacrylamide gel electrophoresis in the presence of SDS. The partial amino acid sequence revealed these proteins have EF-hand structures and high homology to the predicted proteins, calcyclin, calvasculin, and calmodulin. Calcyclin and calvasculin have been considered as probably having roles in the control of cell proliferation, but the existence of these two proteins in platelets suggests that they have other intracellular functions related to the Ca(2+)-signal transduction system.     

Both D factor/LIF and IL-6 inhibit the differentiation of mouse teratocarcinoma F9 cells

Differentiation-stimulating factor (D factor)/leukemia inhibitory factor (LIF) and IL-6 are reported to be cytokines having multifaced functions including the induction of differentiation in mouse myeloid leukemia M1 cells. We here report that both D factor/LIF and IL-6 inhibit the differentiation of mouse teratocarcinoma F9 cells induced by retinoic acid alone or combined with dibutyryl cAMP. From the microscopic observation as well as Northern blot analysis using cDNA probes encoding several marker proteins for differentiation of F9 cells, we concluded that D factor/LIF and IL-6 are functionally closely related in the induction of differentiation in M1 cells and in the inhibition of F9 differentiation.     

Characterization of a factor inducing differentiation of mouse myeloid leukemic cells purified from conditioned medium of mouse Ehrlich ascites tumor cells

A factor inducing differentiation of mouse myeloid leukemic cells (MI) into macrophages was purified to apparent homogeneity from 168 1 of CM of Ehrlich ascites tumor cells. The purified factor was half-maximally active at 2 X 10(-11) M. The factor was analyzed by radioiodination, SDS-polyacrylamide gel electrophoresis and autoradiography. Its Mr was 40 000-50 000. On reduction, the factor lost activity, but showed no subunit structure. Treatment of the factor with endo-beta-N-acetylglucosaminidase F, but not endo-beta-N-acetylglucosaminidase H, gave rise to a molecule of Mr 20 000-28 000. The activity of the factor from Ehrlich cells was completely neutralized by antiserum to the factor of Mr 50 000-70 000 from mouse fibroblast L929 cells.     

Heterotypic induction of stomach-like glands in the urogenital sinus endoderm under the influence of stomach mesenchyme of foetal rats

Summary Urogenital sinus endoderm of 16.5-day rat foetuses was combined with stomach mesenchyme and the recombinants were either treated with testosterone and grown in vitro or cultured beneath the kidney capsule of adult male rats of the same strain. It was found that testosterone stimulated mitosis in the urogenital endoderm. In recombinants grown under the kidney capsule a stratified squamous epithelium and stomach-like glands were induced under the influence of the forestomach and glandular stomach mesenchymes. However, the induced glands expressed neither rat pepsinogen nor rat ventral prostatic antigen. They did not produce mRNA for the prostatic steroid-binding protein C1. Thus, stomach mesenchyme of rat foetuses induces organ-specific morphogenesis but not functional differentiation in the heterologous endoderm, indicating that cytodifferentiation does not always accompany morphogenesis.     

Synthesis of Ethyl Tfa- and Tfp- Amino Acid-p-Aminobenzoates and Their Juvenile Hormone Test

Adipocytes can function as endocrine cells secreting a variety of adipocytokines including tumor necrosis factor (TNF)-α. Treatment of cultured mouse 3T3-L1 preadipocytes with TNF-α induced apoptosis, as was evident from increases in nuclear condensation and caspase-3 activity, but differentiated adipocytes during the maturation phase showed resistance to apoptosis by TNF-α. Antioxidants effectively reduced TNF-α-induced apoptosis in preadipocytes, indicating the involvement of reactive oxygen species. Exposure of preadipocytes to calcium ionophore A23187 reduced TNF-α-induced apoptosis, which was accompanied by increased production of prostaglandins (PGs) E₂ and PGF_2α. TNF-αpreferentially promoted gene expression of cyclooxygenase (COX)-2 without affecting that of COX-1. Consistently, NS-398, a COX-2 inhibitor, stimulated TNF-α-induced apoptosis, which was reversed by exogenous PGE₂ and PGF_2α. These results indicate that endogenous PGE₂ and PGF_2α synthesized by preadipocytes through the induction of COX-2 can serve as anti-apoptotic factors against apoptosis by TNF-α.     

Physical,behavioral, and hormonal changes in the resumption of sexual receptivity during postpartum infertility in female bonobos at Wamba

Primates - The operational sex ratio (OSR) is used as a predictor for the intensity of mating competition. While many factors affect the OSR, there tends to be a high male bias in primate species...     

Discovery of NR2B-selective antagonists via scaffold hopping and pharmacokinetic profile optimization

Selective N-methyl-d-aspartate receptor subunit 2B (NR2B) antagonists show potential as analgesic drugs, and do not cause side effects associated with non-selective N-methyl-d-aspartate (NMDA) antagonists. Using a scaffold-hopping approach, we previously identified isoxazole derivative 4 as a potent selective NR2B antagonist. In this study, further scaffold hopping of isoxazole derivative 4 and optimization of its pharmacokinetic profile led to the discovery of the orally bioavailable compound 6v. In a rat study of analgesia, 6v demonstrated analgesic effects against neuropathic pain.     

Pyrrolinone derivatives as a new class of P2X3 receptor antagonists Part 2: Discovery of orally bioavailable compounds

Some P2X3 receptor antagonists have been developed as new therapeutic drugs for pain. We discovered a novel chemotype of P2X3 receptor antagonists with a pyrrolinone skeleton. Because of SAR studies to improve bioavailability of lead compound 2, compound (R)-24 was identified, which showed an analgesic effect against neuropathic pain by oral administration. We constructed a human P2X3 homology model as a template for the zebrafish P2X4 receptor, which agreed with SAR studies of pyrrolinone derivatives.     

Porin Associates with Tom22 to Regulate the Mitochondrial Protein Gate Assembly

1. Download high-res image (139KB)
2. Download full-size image