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R Eversole

Publications and source records attributed to R Eversole.

8 recordsLinked to original sources

Midline destructive lesions of the sinonasal tract: simplified terminology based on histopathologic criteria.

BACKGROUND AND PURPOSE: Destructive lesions of the sinonasal tract, lacking a discernible etiology and referred to as midline destructive disease, have been pathologically classified in accordance with a variety of confusing terms. Development of new pathologic concepts and immunohistochemical techniques has provided a fresh understanding of these lesions, and, as a result, they can be unified into two distinct pathologic groups: Wegener's granulomatosis and non-Hodgkin's T-cell lymphoma. METHODS: We retrospectively reviewed the imaging studies and pathologic specimens of seven patients with prior diagnoses included in the midline destructive disease group. The specimens were reviewed by an oral pathologist using currently accepted pathologic criteria and the newly available immunohistochemical markers CD20, CD45, and CD45RO. Lesions were classified as non-Hodgkin's T-cell lymphomas when positive for CD45 and CD45RO and negative for CD20, and as Wegener's granulomatosis in the presence of noncaseating multinucleated giant cell granulomas and necrotizing vasculitis. RESULTS: Three of the lesions were reclassified as Wegener's granulomatosis and four as T-cell lymphomas after applying these pathologic criteria. There were no distinguishing imaging findings between Wegener's granulomatosis and non-Hodgkin's T-cell lymphoma. CONCLUSION: The current pathologic classification for midline destructive disease should be incorporated into the radiologic lexicon and the use of terms from the old classification system, such as idiopathic midline granuloma and lethal midline granuloma, should be abandoned and no longer be used in radiologic reports.

Antigens, CD20↗

Changes in the morphology and the distribution of rat intestinal eosinophils during infection with the nematode Nippostrongylus brasiliensis.

Increases in the numbers of eosinophil leukocytes present in the lamina propria of intestines infected with nematodes is a well described phenomenon, yet the role of these leukocytes and their actions in this situation are not yet fully understood. Morphologic changes in these cells occur with the course of the infection, as do alterations in their location within the gut; these findings may give important clues to the function of this prominent cell. We observed changes in intestinal eosinophils in the August rat during infection with the nematode Nippostrongylus brasiliensis and found, together with the well known increases in number infiltrating the lamina propria at Day 20 (three times the levels in normal animals), a distinct change in the morphology of individual cells which included increase of the cell's overall size and changes in shape, as well as a dissemination of cytoplasmic granules in relationship to the cell's nucleus. No ultrastructural evidence of extracellular degranulation or intact eosinophil cytoplasmic granules outside the bounds of cell cytoplasmic membranes was seen. This finding is important considering the light microscopic appearance of individual eosinophil granules apparently distributed extracellularly, and lying in the connective tissue of the lamina propria, a common histopathologic observation in eosinophilic conditions. Eosinophils within the lamina propria changed their location as the infection progressed, tending to move to line up along the subepithelial zones. In addition, eosinophils were observed both at the light and electron microscopic levels to be passing through the basement membrane and into the epithelial layer. This latter phenomenon was confirmed using confocal optical slicing where eosinophils were commonly observed on the luminal side of the nuclei of the gut epithelium. These observations strongly suggest that morphologic alterations occur in eosinophils in the lamina propria and these changes may be associated with functional alterations in these cells akin to the putative phenomenon of "activation." Our findings indicate that eosinophils have the capacity to enlarge and extend their cytoplasmic processes between various components of the lamina propria and move toward the basement membrane during an active infection, as well as into, and possibly through, the intestinal epithelium. These findings emphasize the need for careful consideration of the changing morphologic status of eosinophils when investigating biologic changes associated with the activation of these cells in tissue inflammatory responses.

Animals↗

Multiple anti-cytokine activities secreted from tanapox virus-infected cells.

Tanapox virus (TPV) produces a mild disease in humans characterized by transient fever, one or more nodular skin lesions and regional lymphadenopathy. We demonstrate that TPV-infected cells, but not mock-infected cells, secrete an early 38 kDa glycopeptide that, unlike any other known protein, binds to human (h) interferon-gamma, hIL-2 and hIL-5. In concomitant experiments this polypeptide failed to bind to hIL-1 alpha, hIL-3, hIL-4, hIL-6, hIL-7, hIL-8 or hIL-10. Inhibition of hIL-2 and hIL-5 biological activities were demonstrated using a hIL-2-dependent mouse T cell line (HT-2) and a hIL-5-dependent erythroleukemia cell line (TF-1), respectively. The 38 kDa polypeptide also inhibited the bioactivity of interferon-gamma. Taken together, our results suggest that TPV has evolved multiple pathways to disarm both TH1 cell-mediated (IL-2 and interferon-gamma) and TH2-associated (IL-5) immune responses for its infectivity with remarkable genetic economy.

Animals↗

Ultrastructural alterations in ileal M cells of rats after chronic ethanol ingestion: reversal after cessation of ethanol.

Membranous (M) cells within the dome epithelium of ileal Peyer's patches have been shown to provide selective antigen entry for mucosa-associated lymphoid tissue. This study produced morphologic evidence of ethanol-induced disruption of the architecture in follicle-associated epithelium. The adherens type junctions of the lateral plasma membranes between M cells and columnar absorptive cells were disrupted. A 45-day exposure by ingestion of ethanol also produced marked changes in the ultrastructure of M cells. All experimental animals showed mitochondrial swelling with loss of matrix density, dilation of the endoplasmic reticulum and cytoplasmic vacuolization. The ethanol content of serum and chyme samples were 180 mg/dl and 160 mg/dl, respectively. This was well below the 4,280 mg/dl of the diet therefore a systemic mechanism was implicated for the changes observed. Membranous cells from the recovery group were normal 15 days after withdrawal from ethanol. We concluded that the ethanol-induced cytopathology in ileal M cells is reversible when ethanol exposure is discontinued.

Animals↗

Diascopy: a clinical technique for the diagnosis of vascular lesions.

Dentists can quickly determine the vascular nature of many intraoral lesions by applying a clinical test for blanchability. Such a clinical test is called a diascopy. Described here are the circumstances in which diascopy can be used in a dental practice and what useful information is provided by performing diascopy on oral mucosal lesions.

Diagnosis, Differential↗