Life Sciences Commons^™

The Allantois And Chorion, When Isolated Before Circulation Or Chorio-Allantoic Fusion, Have Hematopoietic Potential, Brandon M. Zeigler, Daisuke Sugiyama, Michael Chen, Yalin Guo, K. M. Downs, N. A. Speck

Dartmouth Scholarship

The chorio-allantoic placenta forms through the fusion of the allantois (progenitor tissue of the umbilical cord), with the chorionic plate. The murine placenta contains high levels of hematopoietic stem cells, and is therefore a stem cell niche. However, it is not known whether the placenta is a site of hematopoietic cell emergence, or whether hematopoietic cells originate from other sites in the conceptus and then colonize the placenta. Here, we show that the allantois and chorion, isolated prior to the establishment of circulation, have the potential to give rise to myeloid and definitive erythroid cells following explant culture. We further …

Effects Of Chemical Aneuploidogens On Taxol Purified Drosophila And Mouse Brain Microtubules Polymerization And Depolymerization In Vitro, Anil Sehgal

Biological Sciences Theses & Dissertations

The effects of aneuploidogens (aneuploidy causing agents) on taxol-purified microtubules from Drosophila and mouse brain in vitro were studied by using a spectrophotometric assay and electron microscopy. Colchicine, acetonitrile, propionitrile, acrylonitrile, dimethyl sulfoxide (DMSO), griseofulvin and cadmium chloride inhibited microtubule polymerization whereas methoxyethyl acetate (MEA) and methyl mercuric chloride (MMC) did not. All aneuploidogens tested (at 50mM) resulted in reduced rate of elongation of mouse brain microtubules. MMC, cadmium chloride and DMSO resulted in increased rates of Drosophila microtubule elongation whereas the rest of the drugs resulted in decreases. The in vitro results from Drosophila correlate well with the previously …

Determination Of N,N'-Diphenylguanidine In Biological Tissues And Fluids Using High Pressure Liquid Chromatography, Edward Sidney Hunter Iii

Chemistry & Biochemistry Theses & Dissertations

N,N'-Diphenylguanidine (DPG) is a potentially toxic compound used in the vulcanization of rubber products. Distribution of DPG in hybrid mice (C57BL/6J interbred with DAB₂) was determined following intraperitoneal injection. Urine, fecal material, whole blood and tissues were collected at various times after administration of DPG and the extracts analyzed for DPG by high pressure liquid chromatography. Recovery of DPG from spiked urine and whole blood exceed 90%, however, the recovery of DPG from spiked tissue samples was approximately 70%.

DPG concentration in whole blood reached a maximum within ten minutes and rapidly decreased through 180 minutes after administration …