Intravenous cidofovir treatment for recalcitrant warts in the setting of a patient with myelodysplastic syndrome

Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.     

Age differences in adults' self-reports of memory ability: it depends on how and what you ask

Self-reports of memory abilities and skills were obtained from fifty younger (M = 20.2) and fifty older (M = 68.7) adults. General rating questions (e.g., How good do you feel your memory is?) and specific questions about memory for certain types of content (e.g., people's names) were included. Consistent age-related decrements were found only for general questions, especially those assessing perceived changes over time. Less consistent differences were found for specific questions. Results were interpreted in terms of implications for assessing self-reported memory ability, and in terms of their meaning for research on the relationship between self-reported and actual memory ability.     

Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance

Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy.     

Immunohistochemical localization of prostaglandin H synthase isoenzyme proteins in the gingival tissue of patients with periodontitis

Prostaglandins are inflammatory mediators that are believed to play an important role in the pathophysiology of periodontal disease. Prostaglandin H synthase (PGHS, EC 1.14.99.1) is the rate-limiting enzyme in prostaglandin biosynthesis. The enzyme exists as two separately encoded isoforms. PGHS-1 which is constitutively expressed and PGHS-2 which is induced by inflammatory stimuli. This is the first report describing the expression of the isoenzymes in gingival tissue from patients diagnosed with adult periodontitis. Tissue was fixed in an alcohol-based fixative and embedded in paraffin. Methods were developed using immunohistochemical controls, such that embedded sections could be processed and stained using isoform-specific antibodies and a peroxidase-antiperoxidase immunohistochemistry technique. Along with populations of mononuclear inflammatory cells, endothelial cells and fibroblasts, the gingival epithelial cell layer appears to be a rich and important source of prostaglandin production within the periodontium of patients with periodontitis as detected by this newly developed immunohistochemical staining technique for PGHS-1 and PGHS-2.     

Frequent ongoing T-cell receptor rearrangements in childhood B- precursor acute lymphoblastic leukemia: implications for monitoring minimal residual disease

Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.