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P Ince

Publications and source records attributed to P Ince.

45 records · Page 3Linked to original sources

Anhidrotic and achromians lesions in incontinentia pigmenti.

Three women subsequently shown to have incontinentia pigmenti (IP) presented with white hairless streaks on the limbs as the predominant cutaneous abnormality. Seven other patients with IP diagnosed in infancy were reviewed to establish the frequency of this sign. It was found in all of them, and in the otherwise unaffected mother of three affected girls. A focal absence of sweating in these lesions is reported here for the first time. There are other similarities with anhidrotic ectodermal dysplasia, suggesting a genetic overlap between these two X-linked conditions.

Adolescent↗

A trophic effect of epidermal growth factor (EGF) on rat colonic mucosa in organ culture.

The development of an organ-culture system for rat colonic mucosa has enabled a direct assessment of the effect of epidermal growth factor (EGF) on cell division. An augmented mitotic index (AIm) has been employed to identify changes in cell proliferation. Explants of colonic mucosa from four animals were maintained in a medium containing serum for five days. On the fifth day of culture, half of the explants received fresh medium containing EGF (40 ng/ml) and the remainder (controls) fresh medium only. At 6, 12, 24 and 48 hr thereafter groups of both experimental and control explants received the metaphase-arresting drug vincristine (4 micrograms/ml) for 3 hr prior to fixation. The proportions of vincristine-arrested metaphases within the explants were determined. Analysis of the data indicates that when serum is present exogenous EGF exerts a trophic effect which increases with time (P less than 0.001). In a second experiment colonic explants from four animals were maintained for five days in a serum-free medium and were then divided into groups, each of which received one of a range of concentrations of EGF. The AIm was determined for each group after 36 hr. It was found that increasing concentrations of EGF produce a small but significant increase in cell proliferation (P less than 0.01). This effect, however, was less pronounced than that seen when serum was present. These results suggest that EGF has a trophic action on the colon and interacts with additional factors found in serum.

Animals↗

Three cases of eccrine porocarcinoma.

We report three cases of eccrine poroma, present for many years, in which features were seen suggesting transformation from a benign to a malignant tumour. These changes ranged from in situ Bowenoid dysplasia to frankly invasive squamous carcinoma. The most helpful diagnostic feature in distinguishing the origin of the tumours was the presence of strong cytoplasmic staining for carcinoembryonic antigen (CEA) in cells surrounding, and giving rise to, neoplastic ducts and clefts. Dermatopathologists examining eccrine poromata should examine the lesions carefully for any evidence of malignant change.

Adenoma, Sweat Gland↗

A comparison of crypt-cell proliferation in rat colonic mucosa in vivo and in vitro.

The successful development of a long-term organ culture system has made it possible to perform experiments on rat colonic mucosa in vitro. However, the effect of trauma or the withdrawal of trophic influences in culture may result in the disturbance of proliferation within the tissue. In this paper we describe an investigation designed to characterise the culture system by a comparison of the proliferative parameters in vitro with those in vivo. Stathmokinetic experiments were performed in vivo and in vitro to estimate cell birth rate. Mitotic indices were also calculated. The in vivo birth rate (7.8 +/- 0.8 cells/1000 cells/hour) and the in vitro birth rate for the whole explant (7.7 +/- 0.5 cells/1000 cells/hour) were found to be similar. A study of crypts in the centre and at the edge of the cultured explants, however, indicated that proliferation at the two sites differed markedly, the birth rate at the edge (7.5 +/- 0.9 cells/1000 cells/hour) being approximately twice that at the centre (3.2 +/- 0.9 cells/1000 cells/hour). Provided that this topological difference in proliferation within the explant is recognised the in vitro model, in particular the basal level found at the centre, may still be regarded as a valid system for studying tissue responses to carcinogens and trophic factors.

Animals↗

Demonstration of vincristine resistance in primary intestinal neoplasms in the rat by the 'post-metaphase index'.

A method is described enabling the direct measurement of vincristine resistance in intact tissues in vivo by morphological study. Using the metaphase arresting properties of the drug, counts were made of escaping anaphase and telophase mitotic figures at a range of doses. The proportion of post-metaphase mitotic figures is called the post-metaphase index (PMI). In 95 primary intestinal tumours induced by dimethylhydrazine (DMH) in rats, an increase in resistance to vincristine was shown over normal mucosa (P less than 0.001). The data were analysed by computer modelling and a linear relationship is demonstrated between the logit of the post-metaphase index, and log dose of vincristine. To achieve a PMI of 1% the fitted lines show an enhanced vincristine dose requirement over normal mucosa of 6 times in colonic tumours, and 8 times in small intestinal tumours. Non-neoplastic mucosa from the DMH-treated animals requires an enhanced dose of vincristine of 1.5 times, compared with normal mucosa, to achieve a PMI of 1%. Given current interest in the mechanism of vincristine resistance in cell lines this new approach provides a technique for assessing the resistance of solid tumours, both in vivo and in vitro, and for subsequent experimental manipulation.

Animals↗

Neuropathological substrates of dementia and depression in vascular dementia, with a particular focus on cases with small infarct volumes.

The neuropathological substrates of dementia and depression were evaluated in 30 patients with cerebrovascular disease and significant cognitive impairment (VaD), with a particular focus on patients with small infarct volumes (<15 ml). VaD patients with small infarct volumes had a similar degree of cognitive impairment to those with larger infarct volumes (>15 ml) but were significantly more likely to be depressed and to have areas of microinfarction. A review of individual cases with small infarct volumes suggested that the combination of microinfarction, diffuse white matter disease and perivascular changes, or the overlap of neurodegenerative pathologies and microvascular changes were particularly important. Microinfarction was also significantly associated with major depression.

Aged↗

One year follow-up of parkinsonism in dementia with Lewy bodies.

The progression of parkinsonism over 1 year was evaluated in a prospective cohort of patients (n = 338), suffering from dementia with Lewy bodies (DLB), Alzheimer's disease (AD) or vascular dementia (VaD). Parkinsonism was assessed using the modified Unified Parkinson's Disease Rating Scale. Significant parkinsonism was significantly commoner in DLB sufferers (71%) than amongst patients with AD (7%) or VaD (10%). DLB patients with established parkinsonism had an annual increase in severity of 9%, but progression was more rapid (49% in 1 year) in patients with early parkinsonism. Parkinsonism was frequent at all severities in DLB patients, but usually only present in other dementias when MMSE <10.

Aged↗

Epidermal growth factor receptors in colorectal carcinoma.

Nineteen samples of primary colorectal carcinoma and adjacent mucosa were examined for EGFr expression using radioligand binding assays and immunohistochemical staining with the monoclonal antibody EGFR1. Radioligand binding experiments showed expression of EGFr in both tumour and mucosa in all cases. In tumour samples EGFr levels ranged between 4 and 79 fmole per mg membrane protein (Kd = 0.1-0.4 X 10(-9) M). There was no significant difference in the level of EGFr expression between tumour and mucosa overall. Immunohistochemical staining with the EGFR1 antibody was useful in localising EGFr to epithelial elements although it was less sensitive than ligand binding assays.

Adenocarcinoma↗