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M A Parsons

Publications and source records attributed to M A Parsons.

At least 91 records · Page 5Linked to original sources
PubMed1989

The ultrastructural pathological features of congenital microcoria. A case report.

We describe the light microscopic, immunohistochemical, and electron microscopic findings in a sporadic case of congenital microcoria in a 72-year-old man with senile cataract. We demonstrated a lack of myofilaments and desmin in the stromal cytoplasmic processes of the anterior pigmented cells of the iris, although other features of muscle differentiation were present in these few surviving cell processes that normally form the pupil dilator muscle. Degenerative changes in anterior pigment cells and iris stromal atrophy were thought to be late secondary features of microcoria. The findings suggest that congenital microcoria results from a defect of intermediate filaments in the terminal fetal stages of differentiation of the anterior pigmented epithelial cell of the iris, with absence of myofilaments and consequent failure of development of a functional dilator pupil muscle.

Aged↗
PubMed1989

Carrier detection and prenatal diagnosis in Norrie disease.

We report the use of DNA probes to determine carrier status in three young women from a large kindred with Norrie disease. One of the women requested prenatal diagnosis during pregnancy. In this pedigree, Norrie disease was not characterized by a deletion at DXS7.

Blindness↗
PubMed1989

Estimation of DNA content in uveal melanomas by flow cytometry.

Flow cytometry was used to evaluate ploidy and tumour cycle kinetics in fresh tissue samples obtained from 19 uveal melanomas. The results were compared with other parameters including, histological cell type, tumour size and anatomical location. Three tumours (15.8%) were aneuploid (two mixed cell, one epithelioid cell). Cell turnover was estimated in the 16 diploid tumours by summating the total percentage of cells in S and G2/M phases. We found the mean percentage of cells in G2/M/S to be 5.96% (range 2.2-9.8%). Spindle cell neoplasms appeared to have lower cell turnover rates (4.5 +/- 1.2%) than epithelioid cell turnover (8.4 +/- 1.2%). There was no correlation between cell turnover and either tumour size or anatomical location.

Aged↗
PubMed1989

Fatal haemopathological consequences of general anaesthesia.

A previously healthy 63-yr-old female died following an anaphylactoid response to anaesthesia with thiopentone and suxamethonium. Postmortem findings strongly suggested that disseminated intravascular coagulation played a significant role in her death. The local mechanism behind the reaction is unknown, but the formation of thiopentone-suxamethonium colloid aggregates during induction, may have led to "aggregate anaphylaxis".

Anaphylaxis↗
PubMed1989

Microassay for prostatic androgen receptors correlated with quantitative histological assessment.

A new microassay in which cryostat sections of prostate tissue were used to provide the source of soluble androgen receptor for biochemical assay, was devised using an isoelectric focusing method, with [3H]-mibolerone as the androgenic radioligand. Adjacent cryostat sections from the same tissue block were stained for diagnostic and quantitative histological assessment. The assay was used to illustrate variations in tissue androgen receptor concentration for correlation with epithelial cell content in benign prostate hyperplasia and prostatic cancer, and to show the effects of androgen receptor concentration of resection of prostatic tissue by electroresection. The results indicate that the heat in electroresection renders prostatic tissue unsuitable for androgen receptor assays, and suggest that knowledge of the cellular composition of carcinomatous prostates may be of importance in the full assessment of androgen receptor assay results. This method incorporates both a biochemical assay and histological assessment of the assayed tissue on near-facsimile sections, an advantage over conventional biochemical assays.

Adenocarcinoma↗
PubMed1989

Sex-steroid receptors in the diethylnitrosamine model of hepatocarcinogenesis: modifications by gonadal ablation and steroid replacement therapy.

The results of this study confirm our previous report of increased androgen receptor expression in livers of female SUAH Wistar rats during development of liver tumours induced by diethylnitrosamine (DENA). In adult female rats not treated with DENA, removal of the ovary increased liver androgen receptor levels but testosterone did not further enhance the androgen receptor status of ovariectomized rats. In normal adult males the testis and/or testosterone maintained high levels of androgen receptors but oestrogen reduced them in castrated rats. Oestrogen receptor levels were not significantly changed in either males or females by gonadectomy. Treatment of female rats with DENA for 10 and 16 weeks increased liver androgen receptors but oestrogen receptors were only reduced by 16 weeks of DENA treatment, whether the rats were intact or ovariectomized. Concentrations of liver androgen receptors were increased in intact and castrated male rats by 10 and 16 weeks of DENA treatment, an increase not seen in the previous experiments. Oestrogen appeared to inhibit both the increases in liver androgen receptor expression and liver tumour development in rats treated with the weakly carcinogenic dose of 10 weeks of DENA. However, the full carcinogenic dose of 16 weeks of DENA increased liver androgen receptors and decreased oestrogen receptors in female rats regardless of sex-steroid status. Development of malignant hepatocellular carcinoma (HCC) was associated with both an increase in liver androgen receptors and a decrease in oestrogen receptors. Maintenance of relatively high levels of liver oestrogen receptors appeared to protect the liver against development of HCC.

Animals↗
PubMed1988

Increased hepatic androgen receptor expression in female rats during diethylnitrosamine liver carcinogenesis. A possible correlation with liver tumor development.

This study investigated the relationship between liver tumor development and androgen-receptor expression in diethylnitrosamine hepatocarcinogenesis in Wistar rats (SUAH substrain). Random liver samples were assayed by an isoelectric focusing method, with [3H]mibolerone as androgenic radioligand. After 16 wk of oral diethylnitrosamine treatment there was a greater than 20-fold increase in hepatic androgen receptor concentration in female rats (control group 0.3 +/- 0.07 fmol/mg cytosol protein; test group 8.36 +/- 0.96 fmol/mg cytosol protein; p less than 0.001, unpaired Student's t-test). This coincided with, and may be related to, an accelerated development of neoplastic nodules or hepatocellular carcinoma, or both. Male rats showed slower tumor development and no change in androgen receptor concentrations. This model is the first to demonstrate significantly increased androgen sensitivity in experimental hepatic carcinogenesis analogous to increased androgen receptor expression in human hepatocellular carcinoma. It may provide insight into steroid hormone sensitivity in developing tumors, and a means of testing potential therapeutic use of hormonal manipulation in human liver cancer.

Animals↗
PubMed1988

Adrenaline dacryolith: detection by ultrasound examination of the nasolacrimal duct.

A 73-year-old woman on topical pilocarpine and adrenaline for chronic simple glaucoma for three years presented with a mass in the medial canthus of the right eye. Although dacryocystography showed a dilated and partially obstructed nasolacrimal system, ultrasound examination was able to demonstrate a mass in the nasolacrimal duct. At operation a black dacryolith was found, of the diameter predicted by ultrasound. Histological examination of the dacryolith suggested its derivation from breakdown products of adrenaline.

Aged↗
PubMed1988

Malignant fibrous histiocytoma of the penis.

A 77-year-old caucasian man presented with toxemia and dehydration, with obstruction of the distal penile urethra by a primary malignant fibrous histiocytoma. He died of toxemia and renal failure 6 days after admission.

Aged↗
PubMed1987

Clinicopathological significance of intratumoural variations in elastosis grades and the oestrogen receptor status of human breast carcinomas.

Cryostat sections from seventy-eight female breast carcinomas were assayed for oestrogen receptors by isoelectric focusing. Adjacent cryostat sections stained by Miller's elastic/van Gieson's method were graded for elastosis. Elastosis was similarly graded on near-equatorial paraffin sections from the same tumours. A positive correlation was obtained between elastosis in the near equatorial sections and oestrogen receptor positivity (p less than 0.0005), menstrual status (p less than 0.05) and parity (p less than 0.01) but no correlation was found between these factors and elastosis graded on cryostat sections from the more peripheral areas which had been selected for oestrogen receptor assay. These observations suggest that the central region of breast carcinomas, where connective tissue responses are fully developed, exhibits grades of elastosis with greater clinical significance. This may explain the conflicting published observations on the correlations between elastosis and oestrogen receptor status, which we believe are due to the lack of uniformity in tissue sampling. The possible implications of the absence of significant correlation between elastosis grades and tumour size, nodal status and disease-free interval are discussed.

Breast Neoplasms↗
PubMed1987

Xanthogranulomatous cholecystitis: clinicopathological study of 13 cases.

In a retrospective three year study 13 cases of xanthogranulomatous cholecystitis (XGC) (seven female, six male) were found in 724 gallbladders (1.8%), an estimated incidence of 1.7 cases per 100,000 population per annum. Symptoms often began with an episode of acute cholecystitis and persisted for up to five years. There was extension of xanthogranulomatous tissue into adjacent organs in nine cases. Three patients had fistulae from the gallbladder, one to skin, and two to the duodenum; this is the first report of this complication in XGC. In two patients XGC sufficiently resembled carcinoma for the surgeon to request intraoperative frozen section diagnosis. There was a high rate of postoperative infective complication, with one subphrenic abscess and three wound infections (one fatal), two in patients with fistulae.

Adult↗