Preliminary Validation of Tumor Cell Attachment Inhibition Assay for Developmental Toxicants With Mouse S180 Cells

This study was designed to explore the possibility of using ascitic mouse sarcoma cell line (S180) to validate the mouse tumor cell attachment assay for developmental toxicants, and to test the inhibitory effects of various developmental toxicants. The results showed that 2 of 3 developmental toxicants under consideration, sodium pentobarbital and ethanol, significantly inhibited S180cells attachment to Concanavalin A-coaed surfaces. Inhibition was dependent on concentration, and the IC50 (the concentration tha reduced attachment by 50% ), of these 2 chemicals was 1.2×10-3mol/L and 1 .0 mol/L, respectively. Anoher developmental toxiant, hydmiortisone, did not show inhibitory activity. Two non-developmental toxicants, sodium chloride and glycine were also tested and these did not decrease attachment rates. The main results reported here were generally sindlar to those obtained with ascitic mouse ovdrian tumor cells as a model. Therefore, this study added further evidence to the conclusion that cell specificity does not lindt attachment inhibition to Con A-coated surfaces, so S180 cell may serve as an altemative cell model, especially when other cell lines are unavailable. Furthermore, after optimal validation, it can be suggested that an S180 cell attachment assay may be a candidate for a series of assays to detect developmental toxicants.

Development of spinal deformities in the tight-skin mouse

Tight-skin （TSK） mice are commonly used as an animal model to study the pathogenesis of Marfan syndrome （MFS）, but little is known of their skeletal phenotype and in particular of the development of the spinal deformities, common in MFS. Here we examined growth of the axial skeletons of TSK and wild-type（B6） mice during their period of rapid growth. The whole bodies of mice, 4-12 weeks of age, were scanned after sacrifice, by micro-computed tomography （microCT）. We reconstructed three-dimensional models of the spine and ribs, and measured vertebral body heights and rib lengths using the Mac-based image-processing software ＂OsiriX＂. Although the TSK mice were smaller than the B6 mice at 4 weeks, they experienced an early growth spurt and by 8 weeks the height, but not the width, of the vertebral body was significantly greater in the TSK mice than the B6 mice. Measurement of the angles of scoliotic and kyphotic curves postmortem in the mice was problematic, hence we measured changes that develop in skeletal elements in these disorders. As a marker of kyphosis, we measured anterior wedging of the vertebral bodies; as a marker for scoliosis we measured asymmetries in rib length. We found, unlike in the B6 mice where the pattern was diffuse, wedging in TSK mice was directly related to spinal level and peaked steeply at the thoracolumbar junction. There was also significant asymmetry in length of the ribs in the TSK mice, but not in the B6 mice. The TSK mice thus appear to exhibit spinal deformities seen in MFS and could be a useful model for gaining understanding of the mechanisms of development of scoliosis and kyphosis in this disorder.

Atg7 in development and disease： panacea or Pandora＇s Box？

Macroautophagy is an evolutionarily conserved intracellular degradation system used by life ranging from yeasts to mammals. The core autophagic machinery is composed of ATG （autophagy-related） protein constituents. One particular member of the ATG protein family, Atg7, has been the focus of recent research. Atg7 acts as an Ellike activating enzyme facilitating both microtubule-associated protein light chain 3 （LC3）- phosphatidylethanolamine and ATG12 conjugation. Thus, Atg7 stands at the hub of these two ubiquitin-like systems involving LC3 and Atg12 in autophagic vesicle expansion. In this review, I focus on the pleiotropic function of Atg7 in development, maintenance of health, and alternations of such control in disease.

Generating a reporter mouse line marking medium spiny neurons in the developing striatum driven by Arpp21 cis-regulatory elements

The striatum, as the primary input nucleus in the basal ganglion,plays an important role in neural circuits crucial for the control of critical motivation, motor planning and procedural learning(Kreitzer and Malenka, 2008). Most cells in the striatum are GABAergic, including a large population (90%-95%) of medium spiny neurons (MSNs) and a small population of interneurons.

Individual blastomeres of 4-and 8-cell embryos have ability to develop into a full organism in mouse

Following fertilization in mammals, the zygote initiates the developmental program, which has a transient capacity to generate cell types of both embryonic and extraembryonic lineages, which is defined as totipotency (Condic, 2014). In mice,only zygotes and blastomeres of 2-cell stage embryos are considered totipotent, since they have the ability to develop into a full