Hypopigmented, hyperkeratotic papules in two siblings. Darier's disease.
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Adult↗
Biomedical subjects
R Singal
Publications and source records attributed to R Singal.
Discrete pigmentation after chemotherapy.
Discrete areas of cutaneous hyperpigmentation were seen in two children with metastatic sarcoma who received chemotherapeutic bone marrow ablation with cyclophosphamide, etoposide, and carboplatin prior to autologous bone marrow transplantation. The hyperpigmented patches occurred only in areas of skin occluded by tape, electrocardiogram pads, or elastic bandages. Identical skin findings were reported in five adult women who received intravenous thiotepa and cyclophosphamide. Measurable levels of thiotepa were detected in these patients' serum, skin, sweat, and occluded gauze, suggesting that the chemical was excreted onto the skin surface in sweat and accumulated under occlusive dressing, thus producing some toxic effect on the epidermis or melanocytes resulting in abnormal pigmentation. We suspect that a similar mechanism was operative in our patients to produce the unusual patterned hyperpigmentation, and suggest that this complication may be prevented by minimizing sweat accumulation in areas occluded by adhesive materials.
Adolescent↗
Bone marrow aplasia in B cell chronic lymphocytic leukaemia: successful treatment with antithymocyte globulin.
Pure red cell aplasia is a rare but well known association of chronic lymphocytic leukaemia (CLL). Pancytopenia due to bone marrow aplasia has not been previously described in CLL. A 42 year old man with B cell CLL became severely pancytopenic with bone marrow aplasia. Bone marrow culture resulted in a greatly reduced colony formation. High dose corticosteroids and intravenous immunoglobulin treatment were unsuccessful. Prompt and complete marrow recovery ensued after administration of antithymocyte globulin.
Adult↗
Quantitation of megakaryocytes in normal bone marrow.
A quantitation of megakaryocytes in normal bone marrow biopsies was performed using a simple direct method of counting. In bone marrow biopsies having a mean cellularity of 72% (range of 60% to 85%), the mean number of megakaryocytes per high-power field (450 X) was 1.5 (range of 0.4 to 2.7).
Adolescent↗
Modulation of the connexin26 tumor suppressor gene expression through methylation in human mammary epithelial cell lines.
BACKGROUND: Normal mammary epithelial cells express mainly gap junction connexin 26 (Cx26) that is either reduced or absent in breast cancers. Since connexin gene mutations are rare we examined if Cx26 gene repression is related to hypermethylation. MATERIALS AND METHODS: Five breast epithelial cell lines were examined for Cx26 mRNA expression and hypermethylation. Treatment with a DNA methyltransferase inhibitor, 5-Aza-2'-deoxycytidine (5-Aza-CdR), was carried out to determine if Cx26 gene expression could be upregulated. RESULTS: Cx26 expression was easily detectable in an immortalized human mammary epithelial cell line (MCF-10) and markedly diminished (MDA-MB231) or undetectable in (MCF-7, BT-20, T47-D) breast cancer cell lines. Hypermethylation of the Cx26 5' region was observed in MCF-10 and MCF-7 cells. Treatment with 5-Aza-CdR resulted in slight or no induction in Cx26 expression in breast cancer cell lines. CONCLUSIONS: Hypermethylation is unlikely to be a major mechanism for Cx26 gene repression in human mammary cancer cell lines.
Antimetabolites, Antineoplastic↗