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Biomedical subjects

M J Wilson

Publications and source records attributed to M J Wilson.

At least 109 records · Page 6Linked to original sources
PubMed1992

Induction of specific gelatinolytic proteinases in the lateral prostate of rats by ectopic pituitary grafts.

Activities of plasminogen activator (PA) and gelatinolytic proteinase in the ventral, lateral, and dorsal lobes of the prostate were examined in rats with hyperprolactinemia, which was induced by implantation of ectopic pituitary grafts under the renal capsule. Weight and total DNA content of the lateral lobe increased significantly in rats receiving two pituitary glands as compared with values for the initial untreated group and the muscle-implanted control animals. No change in specific activity of PA was observed in any prostatic lobe for animals of different treatment groups. However, there was a lateral lobe-specific induction of gelatinolytic proteinase activity in pituitary-grafted rats. Two Ca(2+)-independent proteinase activities of approximately 26-28 and 88 kDa, and three calcium-sensitive proteinase activities of 59, 64, and 76 kDa were found in zymograms of lateral prostate extracts of the untreated initial group and the muscle-grafted control. The lateral prostate proteinase pattern of pituitary-grafted animals demonstrated intense activities of approximately 51, 53, 64, 76, and 135 kDa as well as weaker activities of 40, 43, 59, 85, 93, 105, and 125 kDa. Many of these proteinase activities were present in the secretion of the lateral prostate of the untreated initial controls, suggesting that hyperprolactinemia promotes secretion in the lateral prostate. Those proteinase activities that were not in the secretion were probably of intracellular origin and may play a role in cellular remodeling. Castration resulted in a decrease in activities of these proteinases, and this decrease was observed whether the pituitary grafts were retained or removed.

Animals↗
PubMed1992

Metalloproteinase activities expressed during development and maturation of the rat prostatic complex and seminal vesicles.

The objective of this study was to characterize proteinase activities expressed during development and maturation of the prostate gland and seminal vesicles of the rat by using gelatin-and casein-containing SDS polyacrylamide gel zymography. The prostatic complexes of 2- and 10-day-old animals and the individual lobes of the prostate (ventral, dorsolateral, and anterior [coagulating gland]) and the seminal vesicles of 15-day-old animals expressed prominent gelatinolytic activities of approximately 64, 71, and 76 kDa. These activities had properties of metalloproteinases; i.e., they were stimulated by Ca2+ and inhibited by EDTA and EGTA. They were greatly diminished by 52 days of age (immediately postpuberty) and were not detected in the dorsal lobe of the adult. Less active gelatinolytic proteinases with molecular masses of approximately 34 and 43 kDa were expressed in the developing prostatic complexes and individual lobes and seminal vesicles, but they were not detected in postpubertal animals. Weak gelatinolytic activities of 82, 85, and 89 kDa were found in the prostatic complexes; these activities were greatly diminished in all prostate lobes with sexual maturation but were expressed in the seminal vesicles at all ages. A large-molecular-mass Ca(2+)-independent proteinase of 130 kDa or greater was first detected in the dorsolateral prostate at 21 days of age. This activity was expressed in both the lateral and dorsal lobes of the adult but was greater in the lateral lobe. Proteinase activities of about 22 and 26 kDa that were not stimulated by Ca2+ were detected in the ventral prostate at 15 days of age by means of both gelatin and casein gels.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1992

Determining the probability of radioactive materials on properties in Monticello, Utah.

The former uranium mill site at Monticello, UT, is a surplus facility subject to cleanup under the Surplus Facilities Management Program. Surrounding properties contaminated with mill site material are also subject to cleanup and are referred to as Monticello Vicinity Properties. The objective of this study was to determine the probability that a vicinity property not addressed under the Monticello Vicinity Properties project could contain Monticello mill-related residual radioactive material in excess of Department of Energy guidelines. The study was conducted in a short time frame to protect public health. Statistical methods were used to select 48 random properties for radiological screening surveys. Results of this study may be used to predict the potential number of unassessed properties (results suggest approximately 20%) that contain radioactive contamination that exceeds Department of Energy guidelines and will require remedial action.

Environmental Exposure↗
PubMed1991

Simvastatin and side effects.

OBJECT: to investigate the symptomatic and biochemical side effect profile of simvastatin (a new cholesterol lowering drug) following routine use in a specialist hospital outpatient clinic. METHODS: all patients (n = 110) newly commenced on simvastatin at the lipid disorders clinic at the Princess Margaret Hospital in the first ten months of prescription availability were asked to complete a side effects questionnaire and biochemical evaluation at six months of therapy. RESULTS: 76.4% of patients reported experiencing no side effects with 8% of patients spontaneously reporting feeling better since commencing therapy. Nineteen point one percent of patients reported experiencing symptoms they attributed to simvastatin but had continued therapy, while a further 4.5% of patients had withdrawn from therapy because of side effects. The most frequently reported side effects were muscle ache (13.6%), and gastrointestinal symptoms (4.5%). No abnormalities in biochemical safety tests occurred. CONCLUSIONS: the rate of side effects reported with prescription use exceeds that previously encountered in clinical trials. Since simvastatin is considered effective and well tolerated it is likely to receive wide acceptance in the management of high risk hypercholesterolaemic patients. However, this study indicates the need for continued physician awareness of the main symptoms and their frequency amongst those treated with simvastatin.

Adult↗
PubMed1991

Fluvoxamine versus desipramine: comparative polysomnographic effects.

Electroencephalogram sleep measures over a 4-week period were obtained on 35 inpatients with major depression (unipolar) who received either fluvoxamine or desipramine in a randomized double-blind trial. Fluvoxamine showed immediate rapid eye movement (REM) sleep suppression and an alerting effect on sleep continuity measures. In contrast, desipramine administration was associated with REM suppression and sleep continuity improvement. The "alerting" quality of fluvoxamine, similar to other serotonergic antidepressants, appears to be unrelated to a lack of clinical efficacy, but may be related to persistent REM sleep suppression. However, it is premature to comment on the serotonin specificity for REM sleep.

Adult↗
PubMed1991

Immunocytochemical localization of cathepsin D in rat ventral prostate: evidence for castration-induced expression of cathepsin D in basal cells.

Cathepsin D (EC3.4.23.5) is an aspartyl endopeptidase involved in lysosomal proteolysis. Its functional role is uncertain. This study was undertaken to determine the cellular and subcellular distribution of cathepsin D in the normal rat ventral prostate and its possible role in the castration-induced atrophy of the gland. Cathepsin D was localized immunohistochemically to perinuclear lysosomes in secretory cells, in capillary endothelial cells, and, occasionally, in stromal cells of the untreated animal. Castration resulted in an increased number of cathepsin D-positive cells in the stroma within 24 hr. By 48 hr after castration autophagolysosomes formed in secretory cells and apoptotic bodies appeared in the epithelium. Although apoptotic bodies generally contained immunoreactive cathepsin D, a subpopulation of larger apoptotic bodies, which commonly rested on the basement membrane and contained multiple inclusions, were more variable in cathepsin D expression. The induction of cathepsin D in dendritic cells basally oriented in the epithelium was noted at 4 days of castration. These cells had a phagocytic phenotype, were distributed periodically along the basement membrane, and were not found in ductal epithelia. Treatment with actinomycin D or hydrocortisone to reduce the rate of regression of the ventral prostate blocked the appearance of these cathepsin D-positive, basally oriented epithelial cells. Our data indicate that this cathepsin D-positive, phagocytic cell differentiates from a cell resident in the prostatic epithelium. We suggest that it differentiates from basal cells in the secretory tubuloalveolar portion of the gland and that it is involved in the destruction of regressed secretory cells.

Animals↗
PubMed1991

Localization of type IV collagen in the basement membranes of human prostate and lymph nodes by immunoperoxidase and immunoalkaline phosphatase.

The object of these studies was to examine the localization of type IV collagen (Coll-IV) in the basement membranes (BM) of epithelial and stromal elements (smooth muscle, nerves, vessels) in normal, hyperplastic, and neoplastic (primary and metastatic) prostate. We also examined the relationship of Coll-IV distribution to the degree of tumor differentiation (Gleason grading system). We compared immunoperoxidase (IP) and immunoalkaline phosphatase (AP) techniques in these studies and in selected samples we also evaluated immunofluorescence (IF) localization of Coll-IV and the effects of tissue fixation and pepsin digestion. We found that IF localization of Coll-IV was intense in unfixed sections. IP and AP reactions were absent in fixed, paraffin-embedded sections but pepsin treatment yielded intense and uniform reaction products in these same preparations. Both the IP and AP techniques showed similar localization of Coll-IV in the BM of normal, hyperplastic, and well-differentiated tumor. In most of the higher-grade tumors Coll-IV localization was reduced and a similar pattern of distribution was observed after IP and AP techniques. However, in some high-grade tumors the IP technique showed good localization but AP did not, and vice versa. Such discrepancies were noted in the BM of the tumor cells, as well as in the BM of the stromal elements and in lymph nodes with metastatic tumor. Thus, our study shows decreased Coll-IV localization in higher-grade tumors and suggests that the use of a single technique (IP or AP) may exaggerate this apparent loss of Coll-IV BM components. The exact cause of these discrepancies is unknown but they must reflect variable losses in the ability of the tumor cells to form BM, degradation or decreased synthesis of BM components by high-grade tumors, or a combination of the above.

Adenocarcinoma↗
PubMed1991

Heterogeneity in plasminogen activator (PA) levels in human prostate cancer cell lines: increased PA activity correlates with biologically aggressive behavior.

Plasminogen activators (PA), particularly the lower Mr urokinase (u-PA) type, have been associated with tumor cell invasion and metastasis. We have examined the expression of PA by two human prostate cancer cell lines (PC-3 and DU-145) using functional and immunologic techniques. The culture media and cell extracts of the more aggressive PC-3 cell line contained more than two-fold greater PA activity than the relatively indolent DU-145 cell line. Zymographic studies identified the PA expressed as u-PA. PC-3 cells expressed an additional lower molecular weight form of u-PA not noted in DU-145 cells. Heterogeneity in u-PA expression was shown by the fibrin lysis assay, immunohistochemistry, and dual parameter flow cytometry indicating the presence of phenotypically divergent cell populations. Increased u-PA expression may identify those tumor cells that possess aggressive biological potential.

Flow Cytometry↗
PubMed1991

Characterization of gelatin-degrading metalloproteinase activities of the Dunning rat prostate tumor grown in nude mice.

Proteinase activities in the Dunning R-3327 prostatic tumor grown in nude mice and the dorsal lobe of the normal Copenhagen rat prostate were characterized using gelatin-containing SDS-polyacrylamide gel electrophoresis. Calcium-stimulated activities of approximately 33, 42, 64, 71, 76, 85, 98, 115, and 120 Kd as well as a 91 Kd calcium-independent proteinase were detected in the tumor, whereas the dorsal prostate showed calcium-dependent activities of approximately 62 and 80 Kd and a calcium-independent activity much greater than 120 Kd. The zymographic calcium-dependent proteinase patterns in the other rat prostatic lobes (a 62 Kd proteinase in the anterior lobe; 59, 62, and 67 Kd forms in the ventral lobe; and 52, 62, and 72 Kd activities in the lateral lobe) were distinctive from that of the tumor and of the dorsal lobe. The calcium-dependent and -independent proteinases of the tumor were active over a broad range of pH values with optimal activity near pH 8.0-8.4. The calcium-dependent activities were inhibited by EDTA and EGTA. Barium and strontium could partially substitute for calcium. The calcium-independent activities were not affected by these chelators nor by the proteinase inhibitors benzamidine, epsilon-aminocaproic acid, tranexamic acid, hydrocinnamic acid, or iodoacetate. Similarly, the metalloproteinase activities were not affected by the latter inhibitors. There was little change in the predominant molecular forms (64, 71, and 76 Kd) of proteinase following castration of tumor-bearing nude mice; however, the 98 Kd calcium-dependent activity decreased and the 91 Kd calcium-independent activity increased as a result of this treatment.

Adenocarcinoma↗
PubMed1991

Calcium-dependent and calcium-independent gelatinolytic proteinase activities of the rat ventral prostate and its secretion: characterization and effect of castration and testosterone treatment.

Calcium-dependent and calcium-independent proteinase activities were detected in extracts of rat ventral prostate and its secretion by use of gelatin-containing SDS-PAGE zymography. Ca(2+)-independent proteinase activities of 22, 26, and 73-79 kDa and Ca(2+)-dependent activities of 58, 63, and 66 kDa were found in the adult gland. The 26- (most intense activity of gland) and 22-kDa activities were present in secretion and were not expressed in the undifferentiated gland of the 10-day-old animal. The Ca(2+)-dependent activities were also present in the secretion, where the 63-kDa form was more prominently expressed than the 58- and 66-kDa bands. The Ca(2+)-dependent and Ca(2+)-independent proteinase activities both responded to a broad range of pH values in the incubation media. The 73-79-kDa Ca(2+)-independent activities were sensitive to benzamidine and the Ca(2+)-dependent activities were inhibited by EDTA and EGTA. Both Ca(2+)-dependent and Ca(2+)-independent proteinase activities responded to androgenic manipulations. Castration was followed by the appearance of a 35-kDa Ca(2+)-independent proteinase (at 2 days) and a 43-kDa Ca(2+)-dependent proteinase (at 4 days). In the Ca(2+)-independent proteinase group, the 73-79-kDa activities were increased somewhat and the 22- and 26-kDa activities decreased after castration. The Ca(2+)-dependent proteinases of 58, 63, and 66 kDa increased in activity with castration, but activity of the 58-kDa form decreased again at 7 days after castration. Treatment of animals upon castration for 4 days with hydrocortisone prevented these changes in proteinase activities whereas treatment with actinomycin D or tranexamic acid did not. Testosterone propionate replacement therapy of rats castrated for 16 days stimulated the activities of the 22- and 26-kDa and 73-79-kDa Ca(2+)-independent and the 58- and 63-kDa Ca(2+)-dependent proteinases with 4 days of therapy. The activities of the 35-kDa Ca(2+)-independent and the 43-kDa Ca(2+)-dependent proteinases were repressed with 8 days of testosterone treatment. Thus, individual proteinases show differential changes in activity during development and in response to androgenic manipulation: this suggests that in addition to proteinases which are secreted, others may be involved in intracellular functions or in mediating tissue organization changes.

Animals↗
PubMed1990

A stage in glycolysis controls the metabolic adjustments of vertebrate rod photoreceptors upon illumination.

The factors affecting the metabolic adjustments of toad rod photoreceptors were studied by monitoring the oxygen utilization of excised retinas and by measuring rod outer segment ATP and GTP concentrations. Respiratory adjustments upon illumination were observed when glucose or fructose was provided in the perfusate, but not when a glycolytic inhibitor was added to the perfusate containing glucose and pyruvate, or when a substrate beyond glycolysis or from a later stage of glycolysis was substituted for glucose. The amplitudes of the respiratory adjustments to illumination were dependent on the concentration of glucose in the perfusate. The ATP and GTP concentration changes were dependent on respiratory adjustments, including glycolytic effects, and on the levels of illumination. The data suggest a control point within glycolysis for light-induced adjustments of respiration, possibly at phosphofructokinase.

Adenosine Triphosphate↗
PubMed1990

Rabbit hepatocytes in primary culture: preparation, viability and use in studies of propranolol metabolism.

Isolated hepatocyte cultures have become a frequently used model system for investigating drug metabolism. Although rat and hamster hepatocytes are frequently used for this purpose, metabolism in these species differs in many respects from human metabolism. A species with a metabolism more closely resembling that of humans might be more useful. Our in vivo experiments demonstrated that the metabolism of propranolol in the rabbit is more similar to that in humans than in rats or hamsters. We therefore examined the usefulness of rabbit parenchymal liver cells for studies of propranolol metabolism. A detailed method is presented for their preparation and culture, along with data on their viability, structure and protein synthesizing capability. One- or two-day-old hepatocyte cultures were exposed to 10 mumol/L 3H-propranolol from 30 min to 2 hr; metabolites were identified by gas chromatography-mass spectrometry and quantitated by high-performance liquid chromatography. Propranolol metabolism was linear over 1 hr, with 15% of the substrate metabolized during this time. The cytochrome P-450 pathways, which result in ring oxidation and side-chain oxidation, were expressed in a reproducible fashion similar to that found in vivo in humans. The arylhydrocarbon hydroxylase inhibitor alpha-naphthoflavone (100 mumol/L) inhibited side-chain oxidation of propranolol by 90% without affecting ring oxidation. In contrast, chlorpromazine (100 mumol/L) was shown to inhibit ring oxidation of propranolol by 85% without affecting side-chain oxidation. Cimetidine (250 mumol/L) inhibited both pathways by about 50%.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Plasminogen activator activities in the ventral and dorsolateral prostatic lobes of aging Fischer 344 rats.

Plasminogen activator (PA) activities were measured in extracts of ventral and dorsolateral prostate lobes in Fischer 344 (F344) rats of different ages. Ventral prostates of 30-month-old animals demonstrated widespread epithelial atrophy, some foci of inflammation, intraglandular atypical hyperplasia and/or adenocarcinoma, and a marked increase in PA activities compared with younger animals. Both low- and high-molecular-weight forms of activator were found in zymograms and both forms of activator showed an increase at 30 months. However, the PA activity of the aged rats showed a greater resistance to amiloride inhibition, suggesting a greater relative increase in the tissue-type activator activity than that of urokinase. These changes were not observed in the dorsolateral prostate. The lobe-specific changes in activator activity appear related to dysplasia/neoplasia and not aging.

Aging↗
PubMed1990

Gelatinolytic proteinase activities in human seminal plasma.

Proteinase activities in human seminal plasma were detected using gelatin-containing sodium dodecyl sulphate-polyacrylamide gel electrophoresis zymography. Three prominent bands of activity of Mr 60,000, 66,000 and 90,000 were observed as well as 9 other bands of less intensity (34,000-158,000). These proteinases were dependent upon calcium for optimal activity, did not hydrolyse casein, and were predominantly in the soluble portion of seminal plasma. Examination of seminal plasma of men with different sperm concentrations, split ejaculates, and prostatic secretions indicated that the prostate gland was a source of most of these activities. Proteinase activities of Mr 34,000, 37,000, 82,000 and 120,000 were expressed more frequently in seminal plasma from normozoospermic men than from seminal plasma of oligo- or azoospermic men, indicating that they may also arise from spermatozoa in the semen sample. The proteinases of Mr 60,000 and 66,000 were found in all seminal plasmas whereas there was variation in the expression of the other molecular forms of enzyme, even in the normozoospermic samples. There are multiple forms of gelatinolytic proteinase activities in human seminal plasma which appear to arise from multiple sources in the reproductive tract including the Cowper's/urethral glands, the prostate gland, seminal vesicle and/or spermatozoa. Their function(s) in semen remains to be established.

Electrophoresis, Polyacrylamide Gel↗
PubMed1989

Primary cardiac lymphoma.

An 80-year-old man who initially presented with a left hemiparesis rapidly developed right-sided heart failure and died. Although an echocardiogram suggested the presence of a tumor, the diagnosis of a primary cardiac lymphoma was made only at autopsy. The tumor involved a leaflet of the tricuspid valve, a finding not previously reported in the literature. In 1977, the Armed Forces Institute of Pathology defined a primary malignant lymphoma of the heart as that involving only the heart and pericardium. Many reports of primary cardiac malignant lymphomas have been published, however, most of which mention the presence of metastases. We have reviewed the world literature to determine the number of actual cases of primary malignant lymphoma of the heart. Only 15 reported cases, including the current case, were found to meet the current criteria.

Aged↗