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D S Wilkinson

Publications and source records attributed to D S Wilkinson.

At least 19 recordsLinked to original sources
PubMed1992

Nuclear enlargement induced by hepatocarcinogens alters ploidy.

Treatment of rats with low doses of hepatocarcinogens is associated with a number of phenomena, including nuclear enlargement and altered nucleocytoplasmic compartmentation, which potentially reflect initiatory changes. Since a number of investigations have indicated that changes in ploidy may relate to the development of altered foci and/or hepatocellular carcinomas in liver, and since nuclear enlargement may be associated with changes in DNA content, we examined the ploidy of rat hepatocytes following essentially nontoxic low-dose carcinogen treatment. Treatments with thioacetamide, 2-acetylaminofluorene, or dimethylnitrosamine were all associated with a notable shift of nuclei from diploid to tetraploid, in the apparent absence of nuclear replication. These changes were similar in magnitude to that associated with the substantial liver regeneration induced by carbon tetrachloride. If it is argued that cell replication is a necessary prerequisite for the completion of initiation, these data suggest that there may be thresholds for initiation.

2-Acetylaminofluorene↗
PubMed1992

Dermatitis artefacta as the presenting feature of auto-erythrocyte sensitization syndrome and naproxen-induced pseudoporphyria in a single patient.

A female patient presented with two episodes of apparent dermatitis artefacta. Although it was clear that self-induced lesions were present on both occasions, there was also strong evidence in support of auto-erythrocyte sensitization syndrome on the first occasion and of naproxen-induced pseudoporphyria on the second occasion. The occurrence of two such rare disorders in a single patient is extremely unusual, and we discuss a possible pathogenetic link between them. The case emphasizes that patients with apparent artefactual lesions, or with a previous history of dermatitis artefacta, still require careful evaluation to identify organic disease.

Adolescent↗
PubMed1992

Discerning malignancy in human adrenocortical neoplasms: utility of DNA flow cytometry and immunohistochemistry.

In order to evaluate more objective laboratory methods that may help practicing pathologists to discern malignancy in human adrenocortical neoplasms, we have examined cellular DNA content by flow cytometry and immunohistochemical distribution of c-myc, vimentin, proliferating cell nuclear antigen (PCNA), and epidermal growth factor receptor (EGFR) in 15 cases of human adrenocortical neoplasms (nine carcinomas and six adenomas). All of these examinations were performed on routinely processed surgical pathology specimens. All carcinoma cases met Weiss's histologic criteria. Seven of eight adrenocortical carcinomas demonstrated aneuploid DNA content, while all adenomas were diploid by flow cytometry. c-myc oncoprotein was observed both in cytoplasms and nuclei in all carcinomas but only in nuclei in adenomas. Vimentin was present in all carcinoma cases examined but was also observed in three of six cases of adenoma. There were no clinical or histologic differences between vimentin-positive and vimentin-negative adenomas. Immunoreactivity of PCNA and EGFR was observed in all the cases examined. There were no significant differences in distribution or patterns of immunoreactivity between adrenocortical carcinoma and adenoma. Therefore, we conclude that only DNA ploidy examined by flow cytometry and immunolocalization patterns of c-myc oncoprotein expression have any practical value in the pathologic evaluation of adrenocortical neoplasms. Careful morphologic and/or clinical studies are still considered to be the best available methods in discerning malignancy in resected human adrenocortical neoplasms.

Adenoma↗
PubMed1990

Serous papillary adenocarcinoma of the endometrium. Analysis of proto-oncogene amplification, flow cytometry, estrogen and progesterone receptors, and immunohistochemistry.

Primary and metastatic tumor tissues of serous papillary adenocarcinoma of the endometrium were examined for the following: (1) amplification of int-2, c-erbB-2 and c-myc proto-oncogenes by Southern blot hybridization; (2) DNA ploidy by flow cytometric study; (3) and expression of specific proteins, such as estrogen and progesterone receptors, keratin, vimentin, and carcinoembryonic antigen (CEA) using immunohistochemical and biochemical techniques. Amplification of c-myc was observed in the specimens from the endometrium (ten-fold) and from omental metastasis (five-fold). Both int-2 and c-erbB-2 amplification were not observed. The tumor showed aneuploidy, with the specimens from the endometrium and omental metastasis exhibiting multiple populations of aneuploid tumor cells. Estrogen and progesterone receptors could not be detected biochemically; however, immunohistochemically, estrogen receptors were observed in tumor cells forming papillary structures but not in the tumor cells of the solid, more poorly differentiated areas. A similar distribution was observed for both low and high molecular weight keratin. The findings of c-myc amplification and aneuploidy in the serous papillary adenocarcinoma of the endometrium are consistent with its aggressive behavior observed clinically and emphasize the importance of distinguishing this lesion from other types of endometrial carcinoma.

Blotting, Southern↗
PubMed1979

Perioral dermatitis: a 12-year review.

A continuing study of perioral dermatitis over a period of 12 years is presented. A distinction is made between various patterns of circumoral and paranasal dermatitis and the clinical picture that we describe as "perioral dermatitis". No cases were seen before 1966 but the number of patients presenting to hospital clinics or in private practice rose dramatically until 1970-1972, after which there has been a progressive fall in numbers. In this period, 259 patients were diagnosed as having the condition and of these 203, resident in an area of some 275,000 population and seen by one or other of us on at least two occasions, form the basis of this study. There were 173 females, fifteen males and fifteen children under 12 years of age. In many cases it was possible to suggest the primary lesion for which patients sought treatment. In sixty-nine patients this consisted of a para-oral eruption on the side of the chin and, in forty-one a paranasal erythematous dermatitis. The characteristic appearance and spread of the eruption to the glabella and eyelids are described. A few patients, mostly male, showed lesions around the eyelids only, from treatment of seborrhoeic dermatitis. All but nine of the patients acknowledged the use of potent (not necessarily fluorinated) topical corticosteroids over long periods; in many cases these were self-administered. Some of the children had been treated with preparations intended for their mothers. The numerous aetiological agents that have been incriminated as causes of this eruption are examined. We believe that the prolonged use of topical potent corticosteroids is the only one tenable from our observations. The role of hormonal factors and of local irritant agetns is examined in this context. Tetracyclines are curative in the great majority of patients in 6 weeks if local corticosteroids are discarded. Relapses are rare. Perioral dermatitis is a most satisfying condition to treat but several questions remain unanswered. The current "revolt" against all forms of cortisone may enable us to answer some of these in the near future.

Administration, Topical↗
PubMed1979

Thiomersal.

Explore the source record for details and available documents.

Dermatitis, Contact↗
PubMed1979

Comparison of patch test results in two adjacent areas of England-I. (Industrial allergens).

A 3-year study of patch test reactions to the Standard European Battery has been carried out in two adjacent areas of S. E. England with the same climatic and cultural background. The source of materials and method of testing were identical; both observers had worked together in the same Contact Dermatitis department and the interpretation of reactions can therefore be considered to be consistent. The main differences between the two areas lay in the pattern of employment and of local medicament prescribing. The first only is examined here. One area was dominated by the automobile industry, the other by the furniture industry, with important subsidiary rubber, foam and electronics factories. The pattern that emerges shows that patch test reactions to the Standard European Battery were more likely to be related to environmental allergens and medicament usage than to industrial hazards. Chrome dermatitis was less common than elsewhere in Europe but nickel sensitivity showed the same pattern. Rubber chemical sensitivity reflected industrial, as well as domestic usage. Colophony and formaldehyde appeared to have less industrial significance than we expected. Special additional industrial allergens are not considered here but were of particular importance in the furniture industry. Although the numbers analysed were relatively small, we believe that they reflect the pattern to be expected in areas of relatively low industrial risk in Great Britain at the present time.

Allergens↗