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C Bartram

Publications and source records attributed to C Bartram.

48 records · Page 3Linked to original sources

T cell receptor alpha expression in B-type chronic lymphocytic leukemia.

Normal B lymphocytes are characterized by rearrangement and expression of immunoglobulin genes, but not of T cell receptor genes. These properties might assist in lineage assignment, but there are examples of fresh leukemic cells and of cell lines where exceptions to this rule have been noted. We have studied cell samples of patients with B-CLL for expression of TCR alpha and beta chain genes. Using in situ hybridization with fluorescein-labeled probes, TCR alpha mRNA was found to be expressed in 14 of 18 samples and TCR beta mRNA in 7 of 16 samples. Specificity of hybridization was demonstrated by near complete blockade of TCR alpha hybridization with unlabeled TCR alpha, but not with unlabeled TCR beta probe. Furthermore, in Northern blot analysis a truncated 1,4 kb message for TCR alpha was readily detectable. No significant cell surface staining with the anti-TCR alpha/beta monoclonal antibody WT31 was observed. A contribution of T cells within the leukemic sample could be excluded since only samples with leukemic cell counts of greater than 50,000 cells/mm3 and only samples with 5% or less CD2+ T lymphocytes were studied. Our data show that a large proportion of B-CLL samples may express a truncated version of the TCR alpha message, indicating that this gene can be activated in leukemic B cells frozen at a late stage of differentiation.

B-Lymphocytes↗

Mutation of Ki-ras and N-ras oncogenes in myelodysplastic syndromes.

Somatic mutation of the N-ras oncogene occurs frequently in de novo acute myeloid leukemia (AML). By virtue of their relation to AML, myelodysplastic syndromes (MDS) provide an in vivo model of human leukemogenesis. By using a strategy for analysis of gene mutation based on in vitro amplification of target sequences by the polymerase chain reaction (PCR) and selective oligonucleotide hybridization we analyzed the mutational status of codons 12, 13, and 61 of Ha-ras, K-ras, and N-ras in peripheral blood (PB) and/or bone marrow (BM) in 34 cases of primary MDS. Mutations at codon 12 of Ki-ras or N-ras were detected in three cases (9%): one of six cases of refractory anemia with excess blasts (RAEB) and two of nine cases of chronic myelomonocytic leukemia (CMML). The nucleotide substitution differed in each. In all cases the mutant allele was detectable in PB cells. A sustained hematologic remission was achieved after low-dose cytarabine therapy in the case of RAEB. Neither case of CMML exhibited signs of disease progression during follow-up at 7 and 12 months. In contrast, four of 31 patients without the ras mutation underwent transformation to AML within 12 months of genetic analysis. We conclude that ras mutations in MDS are heterogeneous and may develop at an early stage during the evolution of MDS. Their detection in PB cells illustrates the potential utility of ras mutation as a clonal marker in myeloid malignancy.

Genes, ras↗

Chronic inflammatory bowel disease in childhood.

The diagnosis of Crohn's disease in childhood has been facilitated by the use of fibreoptic endoscopy with biopsies, complemented by double-contrast radiology. Clinical suspicion leads initially to several relevant blood tests. These are followed by endoscopy and multiple colonic biopsies or barium follow-through studies depending on whether large-bowel or small-bowel disease is suspected. The present approach to diagnosis is based on corroborative investigative techniques-endoscopy, radiology, and histology, The availability of paediatric colonoscopes of small diameter should make it possible for paediatricians to perform limited examinations, but when more extensive endoscopy is indicated the child should be referred to special centres.

Child↗

Pathogenesis of diverticulitis complicating granulomatous colitis.

The involement of diverticula by granulomatous colitis may cause an increased incidence of diverticulitis. Of 21 patients with Crohn's disease and associated diverticulosis who underwent resection, sigmoid diverticulitis was pathologically confirmed in 10 (48%). The clinical recognition of the coexistence of the two diseases is often difficult. The radiological signs of peridiverticulitis complicating granulomatous colitis usually show clear evidence of the underlying pathological changes. They include localized diverticular performation, perhaps with multiple communications via a paracolonic sinus tract, mass pressure from the paracolicabscess, and occasionally some degree of communication with deep fissuring ulcers of Crohn's disease. Because diverticula breach the colonic wall, histological analysis confirm that their involvement by the transmural process of granulomatous colitis predisposes to peridiverticulitis and/or abscess formation.

Aged↗

Radiological diagnosis of recurrent colonic carcinoma at the anastomosis.

The barium enemas of 23 cases of end-to-end anastomosis following resection of a colonic carcinoma demonstrated that the normal anastomosis should be smooth, symmetrical, and have a regular mucosal pattern. In contrast the three patients reported with proven recurrent carcinoma at the anastomosis showed irregular asymmetrical filling defects1. As a base line the anastomosis should be investigated with a limited double-contrast enema examination six weeks after operation. Earlier examinations may show irregularity due to incomplete healing.

Adult↗

Adult Crohn disease: can ileoscopy replace small bowel radiology?

BACKGROUND: This study aimed to document the radiological features and distribution of small bowel Crohn disease (CD) in adults by using a barium follow-through (BaFT) technique and to determine whether disease would be missed or its distribution underestimated if only colonoscopy with ileoscopy were performed. METHODS: The BaFT examinations of 121 adults with proven CD were reviewed retrospectively with respect to the stage and distribution of disease. Colonoscopy with attempted ileoscopy was performed in 37 of these subjects, and the results were compared with radiological findings. RESULTS: A normal villous pattern was visualized in 89 studies (74%). BaFT showed small bowel CD in 71 (59%) of 121 patients studied. The terminal ileum (TI) was the most common site of disease, affecting 62 (87%) of patients with small bowel CD. Forty-six patients (65%) had more proximal small bowel disease, including nine (13%) with a normal TI. BaFT showed early mucosal changes of CD in 52 subjects (73%), which was the sole manifestation in 15 (21%). Ileoscopy was possible in the majority of patients colonoscoped but was not achieved in 14 (38%), nine of whom had CD on BaFT. Of the 23 patients in whom ileoscopy was performed, findings agreed with BaFT assessment of the TI in 22. CONCLUSION: BaFT adequately demonstrates the stage and extent of small bowel CD. The majority of patients with small bowel CD have disease proximal to the TI, which cannot be diagnosed by ileoscopy.

Adult↗