Regina Birchem

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The structure of the extracellular matrix (ECM) of representatives of all four sections of the genus Volvox was examined by a combination of light- and electron-microscopic methods. On the basis of these observations, plus published descriptions of aspects of ECM organization in other members of the order Volvocales, a system of nomenclature is proposed, to(More)
Serum from patients with the acute form of the Guillain-Barré syndrome was applied to cultures containing only rat dorsal root ganglion neurons and Schwann cells. Serum taken from 4 of 10 patients during the first 1-3 weeks of clinical onset had previously been shown to have significant demyelinating activity in this culture system when observed at the(More)
Serum samples from 52 patients with the acute Guillain-Barré syndrome (GBS), 19 patients with other neurological disorders, and 18 healthy volunteers were tested for cytotoxicity in cultures of rat Schwann cells and dorsal root ganglion neurons. The samples were also examined by enzyme-linked immunosorbent assay for IgG and IgM antibodies against various(More)
Reproductive cells (androgonidia) ofVolvox carteri f.weismannia divide to form packets of 64 or 128 sperm cells. The androgonidium morphology, stages of mitosis, and cytokinesis were examined by electron microscopy. The biflagellate androgonidium loses its flagella before mitosis but the flagellar bases at the anterior end of the cell are retained. Two(More)
It is possible to treat dissociated embryonic rat dorsal root ganglia in culture to inhibit proliferation of all nonneuronal cells except Schwann cells. Neurons have been shown to produce a mitogenic stimulus for Schwann cells under these conditions. Additionally, myelin-competent neurons induce Schwann cells to elaborate myelin sheaths. Groups of sibling(More)
The effects of recombinant human alpha tumor necrosis factor (alpha-TNF) were compared with those of cytotoxic serum from patients with the acute Guillain-Barré syndrome (GBS) in myelinated cultures containing only rat Schwann cells and dorsal root ganglion neurons. Alpha-TNF did not damage rat peripheral nervous system tissue in culture. These observations(More)
Serum from approximately 40% of patients with the acute Guillain-Barré syndrome (GBS) selectively destroys myelin and myelin-related Schwann cells in cultures containing only rat dorsal root ganglion neurons and Schwann cells. To determine if the effects of GBS serum on myelin and myelin-related Schwann cells could be mediated through elevations in the(More)
Sudan black B stains oleoresin blue-black in epoxy-embedded material as well as in living tissue. The Sudan black B staining properties of oleoresin are similar to those of lipid, but it can be distinguished from tannin, which stains brown. Pratically all oleoresin present in resin ducts and intercellular spaces, and much of that contained in epithelial(More)
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