Search PubMed⌕ Search

Biomedical subjects

F D Lee

Publications and source records attributed to F D Lee.

At least 55 records · Page 3Linked to original sources

The interaction between Helicobacter pylori culture filtrate and indomethacin: effects on the integrity of human gastric antral mucosa and its prostaglandin E2 production in vitro.

Histopathological methods and radioimmunoassay were used to assess the microstructure and prostaglandin E2 production by paired specimens of human gastric antral mucosa; the specimens were studied after 48 h of incubation in base-line tissue culture medium, Helicobacter pylori culture filtrate, H. pylori culture control fluid, indomethacin, and H. pylori culture filtrate plus indomethacin. When applied alone, the filtrate did not affect the structure of the mucosal tissue or its prostaglandin E2 synthesis. In the overall group (n = 21), specimens incubated with the mixture of H. pylori filtrate and indomethacin had a median histological grade of 1 and prostaglandin E2 of 29 pg/mg tissue, compared to 2 pg/mg (P = 0.04) and 60 pg/mg (P = 0.0007) respectively, in specimens incubated with indomethacin alone. These results indicate that an interaction may exist between indomethacin and a factor contained in H. pylori culture filtrate. Such interaction is damaging to the human gastric antral mucosa, and its understanding might have therapeutic implications.

Adult↗

Observer variability in histopathological reporting of transitional cell carcinoma and epithelial dysplasia in bladders.

Sections from 90 urinary bladder biopsy specimens were examined by 11 consultant histopathologists with varying experience to determine the appropriateness of existing pathology terminology. Analysis with kappa statistics showed fair to good agreement in the grading and staging of transitional cell carcinoma. There was also reasonable agreement in the diagnosis of high grade dysplasia in random biopsy specimens from the urothelium adjacent to the neoplasm, but very poor agreement for lesser degrees of dysplasia. It is concluded that the present classification of bladder carcinomata is reliable and that pathologists can determine stage with a high degree of reproducibility and grade with a fair degree of reproducibility.

Carcinoma, Transitional Cell↗

Gastric antral vascular ectasia (watermelon stomach)--therapeutic options.

We have encountered five cases of chronic iron deficiency anaemia due to bleeding from gastric antral vascular ectasia (watermelon stomach). Two cases were associated with a lymphoma and in three cases there was evidence of portal hypertension. Two patients were treated conservatively by blood transfusions. The other patients required either surgery or tranexamic acid or endoscopic laser therapy to control the chronic haemorrhage.

Aged↗

Abrogation of IL-3 dependent growth requires a functional v-src gene product: evidence for an autocrine growth cycle.

We have investigated the ability of the v-src oncogene to abrogate growth factor dependent growth in the interleukin-3 dependent myeloid progenitor cell line 32D c13. Growth factor independent clones were isolated following infection of 32D c13 cells with murine retroviruses containing the v-src oncogene. v-src was demonstrated to be directly responsible for growth factor independence in experiments utilizing temperature-sensitive v-src mutants. The v-src infected cells released a growth factor capable of stimulating the proliferation of normal 32D c13 cells. Analysis of the mRNA from v-src infected 32D c13 did not identify the putative autocrine growth factor as one of the currently identified murine or human hematopoietic growth factors.

Animals↗

Observer variability in histopathological reporting of cervical biopsy specimens.

Sections from 100 cervical biopsy specimens were studied by 12 consultant histopathologists to determine the robustness of the existing pathology terminology and classification. Analysis by kappa statistics showed good agreement in the diagnosis of CIN 3 and squamous carcinoma but an inability to distinguish accurately between the lesser grades of CIN. It is recommended that the classification be changed to low grade (present CIN 1 and 2) and high grade (present CIN 3) categories alone. There was very poor agreement in the identification of cellular changes associated with human papilloma virus (HPV) infection.

Biopsy↗

Hodgkin's disease.

Explore the source record for details and available documents.

Antigens, Neoplasm↗

Activation of mouse T-helper cells induces abundant preproenkephalin mRNA synthesis.

Antigenic or mitogenic stimulation of T cells induces the secretion of an array of protein hormones that regulate immune responses. Molecular cloning has contributed strongly to our present understanding of the nature of this regulation. A complementary DNA (cDNA) library prepared from a cloned concanavalin A-activated mouse T-helper cell line was screened for abundant and induction-specific cDNA's. One such randomly chosen cDNA was found to encode mouse preproenkephalin messenger RNA (mRNA). Preproenkephalin mRNA represented about 0.4 percent of the mRNA in the activated cell line but was absent in resting cells of this line. Other induced T-helper cell lines have 0.1 to 0.5 percent of their mRNA as preproenkephalin mRNA. Induced T-helper cell culture supernatants have [Met]enkephalin-immunoreactive material. The production by activated T cells of a peptide neurotransmitter identifies a signal that can potentially permit T cells to modulate the nervous system.

Animals↗

The distribution of the c-myc oncogene product in malignant lymphomas and various normal tissues as demonstrated by immunocytochemistry.

The expression of c-myc was studied in 51 malignant lymphomas and in a variety of normal tissues by immunocytochemistry using monoclonal antibodies raised to different synthetic peptides and reacting monospecifically with the c-myc product (p62c-myc). The c-myc product was detected in only a minority of malignant lymphomas principally those containing cells with immunoblastic characteristics, and was predominantly localised to the cytoplasm. In normal lymphoid tissues only plasma cells and histiocytes were found to have immunoreactivity. In non-lymphoid normal tissues, however, the c-myc product was distributed widely. Marked differences in its intracellular distribution were apparent in different tissues. These findings suggest that the relationship of p62c-myc expression to cell division may be more complex than previously suggested by in vitro studies, and raise the possibility that it may have other functions within the cell.

Antibodies, Monoclonal↗

The relation of ras family oncogene expression to conventional staging criteria and clinical outcome in colorectal carcinoma.

The elevated levels of ras-related cellular RNA in a series of colorectal carcinomata (n = 12) was correlated with conventional staging criteria (tumour morphology and Dukes' staging) and with clinical outcome with particular reference to the development of metastatic disease. No direct relationship was evident between these parameters suggesting that although abnormal expression of ras oncogenes may be critical in the development of malignancy, variations in the level of their expression do not appear to be directly related to clinically evident phenotypic differences.

Aged↗