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R S Camplejohn

Publications and source records attributed to R S Camplejohn.

At least 55 records · Page 3Linked to original sources
PubMed1986

DNA flow cytometry of histological material from human gastric cancer.

DNA flow cytometry was performed on fixed embedded histological material from 56 radical gastrectomies for human gastric cancer. The ploidy and proportion of cells in the DNA synthetic phase of the cell cycle (S phase fraction) were estimated and the results correlated with histological features. DNA aneuploidy was encountered in 73 per cent of cases. Aneuploid and diploid tumours both had significantly higher fractions of cells in S phase than normal mucosa. S phase fractions for aneuploid tumours were higher than diploid tumours. There was a trend for tumours exhibiting an infiltrating mode of growth and poor tubule formation to have a diploid DNA content and low S phase fraction. No difference was observed between the results obtained from tumours with or without lymph node metastases. Early uniform fixation greatly improved the quality of the flow cytometry results measurable by a reduction in the mean coefficient of variation.

Cell Division↗
PubMed1986

DNA flow cytometry of human breast carcinomas and its relationship to transferrin and epidermal growth factor receptors.

The expression of transferrin and epidermal growth factor receptors in breast carcinomas, as detected by immunohistochemistry, has been compared with DNA ploidy and S-phase content of the same tumours as determined by DNA flow cytometry of fixed, paraffin embedded tissue, and with tumour differentiation. Good correlations have been found between DNA ploidy, S-phase content and differentiation. The expression of transferrin receptor appears to relate to DNA ploidy, but only to a limited extent to S-phase content, indicating that in breast carcinomas immunoreactive transferrin receptor may not be directly related to proliferation. The presence of epidermal growth factor receptor shows a close correlation with high S-phase content, but only a lesser association with DNA ploidy, and no correlation with tumour differentiation. DNA flow cytometry provides a more reliable method of assessing the relationship of such growth factor receptors in breast carcinomas to cell proliferation, than that obtained from more subjective tumour grading criteria.

Breast Neoplasms↗
PubMed1986

DNA flow cytometry of histological material from dysplastic lesions of human gastric mucosa.

DNA flow cytometry has been carried out on histologically processed human gastric tissue showing varying grades of gastric dysplasia, intramucosal carcinoma and regenerative changes. No cases of DNA aneuploidy were encountered in cases showing regenerative changes or mild or moderate dysplasia. DNA aneuploidy was found in 5/7 cases of severe dysplasia and 3/11 cases of intramucosal cancer. Irregularities of the G0/G1 peak were encountered in a further 18 samples including normal and regenerative gastric mucosa. However these were not thought to indicate DNA aneuploidy. The interpretation of these abnormalities and the affect on the frequency with which DNA aneuploidy is reported in pathological lesions is discussed.

Aneuploidy↗
PubMed1986

Aneuploidy in Bowen's disease.

Distinct aneuploid clones of keratinocytes were detected in six cases of cutaneous Bowen's disease. As Bowen's disease is an accepted precursor of malignancy, aneuploidy may prove to be a useful indicator of the risk of invasive change in dermatoses questionably pre-malignant.

Aneuploidy↗
PubMed1986

Screening tests for Sezary cells in cutaneous T-cell lymphomas.

Blood samples from normal individuals (n = 7), from patients with cutaneous T-cell lymphomas (Sezary syndrome = 7; mycosis fungoides = 18) and from patients with chronic benign skin disease (n = 8) were examined for the presence of Sezary cells. The samples were analysed using a Coulter model S Plus IV with a three Cell Population upgrade, and a Becton Dickinson FACS analyser; and the results were compared with those obtained from morphological examination of peripheral blood films. Using the FACS analyser a population of aneuploid cells was only identified in two out of eight patients with confirmed circulating Sezary cells. This was in contrast to the results from the Coulter S Plus IV which detected an abnormality in six out of the eight samples with confirmed circulating Sezary cells. These results indicate that leukocyte volume analysis is a useful, additional screening tool for the identification of Sezary cells.

Flow Cytometry↗
PubMed1986

Prognostic importance of DNA flow cytometry in non-Hodgkin's lymphomas.

Eighty one cases of non-Hodgkin's lymphoma were examined by DNA flow cytometry, using fixed embedded histological tissue. The frequency of detection of DNA aneuploidy and the values for S phase fractions depended on the histological subtype and grade of lymphoma. Twenty two of the patients with low grade centroblastic/centrocytic non-Hodgkin's lymphoma had repeat biopsies. Eleven of these patients remained histologically and cytometrically stable, but the remaining eleven transformed into high grade non-Hodgkin's lymphoma. The mean value for the S phase fraction in the initial biopsy specimens from patients which transformed was higher than that for patients whose lymphomas remained stable (p less than 0.001). It is proposed that estimates of S phase fraction prospectively identify patients with low grade non-Hodgkin's lymphoma at risk from transformation.

Aneuploidy↗
PubMed1985

Comparison of DNA flow cytometry from fresh and paraffin embedded samples of non-Hodgkin's lymphoma.

Cell suspensions were prepared from fresh and paraffin embedded samples of lymph nodes from nine patients with non-Hodgkin's lymphoma. DNA flow cytometry was performed on these samples and the results from fresh tissue compared with those from paraffin embedded material. Results were compared in terms of DNA index (as a measure of aneuploidy) and S phase fraction (as an indication of proliferative activity). Good agreement was found between the results from the samples prepared by the two methods. The quality of DNA flow cytometry from paraffin embedded material was comparable with or better than that from fresh samples.

Aneuploidy↗
PubMed1985

Study of psoriatic epidermal cell kinetics and cell death after oral methotrexate.

Epidermal cell proliferation in psoriasis was studied after oral methotrexate using tritiated uridine. Psoriatic enteropathy has in the past been reported to reduce the absorption of methotrexate administered orally but this study showed that the onset of inhibition of mitosis and DNA synthesis occurred at the same time as after intramuscular administration of the drug. The cell kinetic data indicate that cells were blocked at the G1/S interface, and the kinetics of inhibition are discussed in terms of their implications for the mode of action of methotrexate in psoriasis. Considerable numbers of dead cells were seen in the epidermis from 6 to 24 h after oral methotrexate. The mode of action of methotrexate in psoriasis is currently unknown but whatever other actions it may have, any global hypothesis of its action will have to incorporate a flux to epidermal cell death.

Cell Survival↗
PubMed1985

The tumour bed effect: a cell kinetic and histological investigation of tumours growing in irradiated mouse skin.

Most tumours grow more slowly when implanted into pre-irradiated sites--the tumour bed effect (TBE). The TBE is usually assayed by measuring the delay for tumours growing in irradiated sites compared with that for tumours growing in mock-irradiated sites to reach a certain arbitrary, externally-measured volume. The resulting X-ray dose-response curves for the TBE are generally S-shaped, with little effect up to doses of 5 Gy, a dose-dependent effect between 5 and 20 Gy and a plateau at higher doses. In this study such a dose-dependent TBE was demonstrated for two contrasting transplantable tumours (a rapidly growing mammary adeno-carcinoma and the RIF-1 fibrosarcoma) growing in the flank skin of C3H/He mice. Cell kinetic and histological methods were used to investigate the mechanism of the reduced tumour growth rate in irradiated sites. By combining information from tumour growth curves and metaphase-arrest lines, tumour cell birth and cell loss rates were estimated. In addition the necrotic and viable fractions of tissue were measured by means of Chalkley point counting. In both tumours, marked increases in cell loss rate and degree of necrosis were found to be dependent on the dose of X rays previously given to the stroma. Surprisingly, cell birth rate and mitotic index were significantly increased in mammary tumours growing in irradiated sites. The estimation of viable, as opposed to external, volume of tumours growing in sites which had received between 0 and 60 Gy X rays suggested that the conventional TBE assay method may underestimate the extent of the TBE and may distort the shape of the TBE dose response curve.

Adenocarcinoma↗
PubMed1985

Combination heparin plus cortisone treatment of two transplanted tumors in C3H/He mice.

C3H/He inbred mice bearing either C3H mouse mammary or RIF-1 tumors of 180-mm3 volume were treated with a combination of heparin (500 anticoagulation U/ml drinking water) plus cortisone (either 250 mg/kg/day tapering to 37 mg/kg/day or a constant dose of 75 mg/kg/day). Five types of heparin were tested in this study. RIF-1 tumors shrank to approximately half the volume at the start of therapy after only 3 days of treatment; mammary tumors took longer to respond, not reaching half the starting volume until after 11 days of treatment. In both tumors response was transient, the tumors eventually regrowing. However, response to combined heparin and cortisone therapy was in fact no different from the response to cortisone used alone. Also, cortisone treatment was extremely toxic to these animals and experiments had to be terminated after about 3 weeks of therapy.

Adenocarcinoma↗
PubMed1984

Mitotic and labelling activity in normal human epidermis in vivo.

Labelling and mitotic indices were studied in the epidermis of twenty-eight young men. A mean labelling index of 5.5% was found from the whole study and a mean mitotic index of 0.06%. Mitotic index particularly was extremely variable; indices between 0.002 and 0.438% were found in individual biopsies. In the first two of three experiments in which mitotic index at 09.00 hours was compared with that at 15.00 hours, significant differences were found (15.00 hours greater than 09.00 hours by a factor of 2.6, P less than 0.001). However, in the third such experiment no such difference was found, suggesting that the timing and occurrence of diurnal rhythms of mitotic activity may not be consistent in normal human epidermis. In the one experiment in which it was investigated, a significantly higher mitotic index was found at 21.00 hours compared to 09.00 and 15.00 hours. Labelling index did not vary significantly at 09.00, 15.00 or 21.00 hours. However, labelling index did show a significant pattern of change over a 12-month period in two groups of subjects; peaks of labelling were seen in July and troughs in January. Very high ratios of labelled: mitotic cells were found, the median ratio for the whole study being ninety-eight labelled: one mitotic cell. This finding supports the possibility that not all labelled cells subsequently go on to divide in normal human epidermis.

Adult↗
PubMed1983

A study of diurnal proliferative activity in tumour and small intestine of C3H mice bearing a transplanted mammary carcinoma.

Diurnal changes in proliferative activity were investigated in tumour and small intestinal epithelium of mice bearing a transplanted mammary carcinoma. In addition to mitotic and labelling index studies, the metaphase-arrest technique with vincristine (VCR) was employed. In the tumour there was no clear evidence of a significant diurnal rhythm in proliferative activity but in the small intestinal epithelium such a rhythm was clearly demonstrated. A higher cell production rate (kB) measured by metaphase-arrest and higher labelling and mitotic indices were seen in the mid to late part of the dark period. The peak mitotic index was seen 3 to 6 h after the labelling peak in the small intestine. The basal third of the crypt which is believed to include the stem cell compartment of this tissue showed larger diurnal fluctuations in both labelling index and kB than the rest of the proliferative compartment.

Animals↗
PubMed1983

Stathmokinetic measurement of tumour cell proliferation in relation to vascular proximity.

In this study the metaphase-arrest method with vincristine (VCR) was used, in a transplanted C3H mouse mammary tumour, to study cell proliferation relative to distance from a blood vessel. The metaphase-arrest method has a number of advantages over methods involving [3H]TdR labelling for such a study. The cell birth rate (kB) was shown to be inversely related to distance from a capillary in corded areas of tumour. Penetration of VCR, even into perinecrotic areas of tumour, appeared to be sufficient to achieve effective metaphase arrest.

Adenocarcinoma↗
PubMed1982

Cell kinetic response of an experimental tumour to irradiation. Use of the stathmokinetic method.

The cell kinetic perturbations following irradiation (20 Gy) were studied by combining the metaphase arrest method using vincristine with histological indices of cell death. The metaphase arrest method yielded remarkably constant values of rate of entry into mitosis (rM) of around 24 new cells/1,000 cells/hour during a 7 day period in which there was no tumour growth. The time course of cell death as indicated by changes in the pyknotic index during this period may reflect the processes of reoxygenation and repopulation known to influence the results of fractionated radiotherapy.

Adenocarcinoma↗