Electron microscopic observation of polyoma DNA component I isolated by CsCl-ethidium bromide density gradient centrifugation.

The DNA extracted from a purified preparation of polyoma virus was separated into two fractions situated in either light or dense bands by CsCl-ethidium bromide density gradient centrifugation. The electron microscopic examination of the DNA in each band showed the molecular configuration of linear and circular DNA, respectively.It was previously considered that the DNA in the dense band consisted component I (closed supercoiled circular DNA) of polyoma virus, however this band contained a number of open circular DNA molecules which increased the length of circumference. The influence of dye binding on the molecular configuration of closed supescoiled circular DNA is discussed

Histo- and Immunopathological Studies on the Allergic Pneumonitis Induced in Sensitized Rabbits by Intravenous Provocative Injection of Ferritin Purified from Horse Spleen.

Histo- and immunopathological studies on the allergic pneumonitis induced in sensitized rabbits by intravenous provocative injection of ferritin purified from horse spleen were presented. The experimental results here obtained have been described and pathogenesis of the pneumonitis has been considered. The fundamental pathologic processes underlying the pneumonitis presented here are said to be characterized by a transformation of alveolar capillaries and intercapillary connective tissue into reticular or enmeshed structure simulating reticular tissue of antibody-forming organs which is induced by localization and fixation of immune complexes in the alveolar walls through the phagocytic activity of cellular components in this structure

Aleukemic leukemia cutis in a patient with Philadelphia chromosome-positive biphenotypic leukemia.

Aleukemic leukemia cutis is a rare condition characterized by the invasion of leukemic blasts into the skin before their appearance in the peripheral blood. Leukemia cutis usually occurs in patients with myeloid leukemia, especially the myelomonocytic and monocytic types of acute myeloblastic leukemia. We describe the case of a 62-year-old woman with aleukemic leukemia cutis who developed Philadelphia-positive acute leukemia 1 month after skin involvement. Leukemic cells expressed both myeloid and B-cell lineage surface markers, and monoclonal rearrangement of the immunoglobulin heavy chain was detected by Southern blot analysis. This report is the first of a case of aleukemic leukemia cutis preceding Philadelphia-positive biphenotypic leukemia

Usefulness of magnifying endoscopic evaluation of the terminal ileum for a patient with graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

The gastrointestinal tract is one of the common targets of acute graft-versus-host disease (GVHD), but accurate diagnosis is difficult because of the nonspecific nature of complicated diseases and the lack of diagnostic findings by conventional endoscopy. Recently, a magnifying endoscope has been developed and used for examining microstructures of the mucosa. Herein, we report the first use of a magnifying endoscope for a patient with gastrointestinal (GI) GVHD. Magnified endoscopic findings of atrophic and coalescent villi of the terminal ileum reflect histological findings of GVHD. Magnifying endoscopy of the terminal ileum may be useful for early detection and follow-up of GI GVHD