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T G Pretlow

Publications and source records attributed to T G Pretlow.

At least 73 records · Page 4Linked to original sources
PubMed1989

Beta-glucuronidase activity in prostatic carcinoma and benign prostatic hyperplasia.

Beta-glucuronidase activity was extracted from prostatic carcinomas and hyperplastic prostates. It was 3.6-fold higher (P less than 0.0001) in prostatic carcinoma than in prostatic hyperplasia. Analysis for isoenzymes of prostatic beta-glucuronidase by disc-gel electrophoresis in nondenaturing polyacrylamide gels demonstrated only one form of the enzyme. Histochemically, enzymatic activity was observed almost entirely in epithelial cells in both prostatic carcinoma and benign prostatic hyperplasia.

Aged↗
PubMed1989

5'-nucleotidase activity in prostatic carcinoma and benign prostatic hyperplasia.

In light of previous reports of alterations in 5'-nucleotidase activity in neoplastic conditions, 5'-nucleotidase activity was examined histochemically in tissue sections and quantified biochemically in extracts of human hyperplastic prostates and prostatic carcinomas obtained surgically. The 5'-nucleotidase activities per mg protein in extracts of 29 prostatic carcinomas were lower (P less than 0.0005) than in extracts from 10 samples of benign prostatic hyperplasia. The 5'-nucleotidase activity per mg protein in extracts of prostatic carcinoma from the 29 patients correlated (R = -0.369, P = 0.049) with the degree of histological differentiation; the extracts of poorly differentiated carcinomas contained low levels of 5'-nucleotidase. When age and histological differentiation (Gleason's grade) were adjusted, the enzyme activity per mg protein correlated (R = 0.242, P = 0.004) with patient survival. When all three parameters were considered together, i.e., histological grade of the tumor, 5'-nucleotidase extracted from the tumor, and age of the patient, they were found to be mutually complementary for the prediction of patient survival (R = 0.388, P = 0.0001). To our knowledge, this is the first report that prostatic epithelium expresses 5'-nucleotidase; further work will be required to define the reasons for the high levels of activity observed in prostates without cancer and for the decrease in the activity in prostatic carcinoma.

5'-Nucleotidase↗
PubMed1989

Enzyme histochemistry of monocytes/macrophages: a study in a murine model of immune complex-mediated glomerulonephritis.

In a model of immune complex glomerulonephritis in BALB/c mice, cells of monocyte/macrophage lineage (M phi), identifiable by electron microscopy, infiltrate the glomerulus. In spite of this, no unequivocal nonspecific esterase activity can be demonstrated histochemically in the glomeruli. On the other hand, many mononuclear cells with strong acid phosphatase activity are consistently present. This observation is in line with other studies that have demonstrated the heterogeneity of enzyme profiles in different M phi populations. Despite the wide acceptance of nonspecific esterases as markers for M phi, the present study indicates that exclusive reliance on a single marker in investigating the participation of M phi in a pathological process can lead to erroneous conclusions. Use of multiple markers and preferably multiple investigative modalities is recommended.

Animals↗
PubMed1988

Velocity sedimentation of cells.

Velocity sedimentation provides a variety of methods for the separation of cells according to their rates of sedimentation. Many approaches are available.

Cell Fractionation↗
PubMed1987

Enzymatic histochemistry of mouse kidney in plastic.

Two-micrometer sections of methacrylate-embedded kidney were used to investigate the enzymatic activities of mouse kidney where the proximal tubule and Bowman's capsule from the same corpuscle were viewed in the same section. Alkaline phosphatase, acid phosphatase, 5'-nucleotidase, gamma-glutamyl transpeptidase, N-acetyl-beta-glucosaminidase, leucine aminopeptidase, alpha-naphthyl butyrate esterase, and adenosine triphosphatase activities were observed in the proximal tubule, but only 5'-nucleotidase, alpha-naphthyl butyrate esterase, and alkaline phosphatase were observed in the squamous portion of the parietal epithelium of Bowman's capsule. The use of methacrylate-embedded tissue allowed more precise localization of enzymatic activity than is possible with most frozen sections. This may provide interesting applications not only for characterization of kidney diseases but also for characterization of other normal and abnormal tissues.

5'-Nucleotidase↗
PubMed1987

Examination of enzyme-altered foci with gamma-glutamyl transpeptidase, aldehyde dehydrogenase, glucose-6-phosphate dehydrogenase, and other markers in methacrylate-embedded liver.

F344 Male rats weighting between 90 and 110 gm were given 90 ppm diethylnitrosamine in their drinking water for 5 weeks. Seven weeks after the administration of carcinogen was completed, the rats were sacrificed and sections of their livers were embedded in methacrylate. Serial sections 2 or 4 micron in thickness demonstrated the presence of gamma-glutamyl transpeptidase, acid phosphatase, adenosine triphosphatase, aldehyde dehydrogenase, alkaline phosphatase, alpha-naphthyl butyrate esterase, DT diaphorase, glucose-6-phosphate dehydrogenase, and 5'-nucleotidase activity and glycogen. The use of 4-micron sections of methacrylate-embedded tissue allows the evaluation of many more phenotypic markers in serial sections than is currently possible with frozen sections.

Aldehyde Dehydrogenase↗
PubMed1985

Cytoplasmic inclusions in hepatocytes of bone marrow transplant patients: light and electron microscopic characterization.

Large eosinophilic, cytoplasmic inclusions were observed at autopsy in the hepatocytes of three patients who received bone marrow transplants for acute leukemia. The eosinophilic inclusions were not associated with any additional specific morphologic change in the liver. While similar inclusions have been observed in rats during hepatic regeneration following partial hepatectomy and in human hepatomas, to the authors' knowledge, such inclusions have not been described previously in patients who have received bone marrow grafts.

Adult↗
PubMed1985

Vascular sarcomas (probably angiosarcomas) transplanted from suspensions of liver cells from diethylnitrosamine-treated rats.

F344 male rats were given 90 ppm diethylnitrosamine in their drinking water ad libitum in two cycles. Livers containing neoplastic nodules, hepatomas, and no sarcomas in the sections sampled were digested in parallel with 0.05% collagenase, 0.1% Pronase, or 0.25% trypsin. Cells were transplanted into 9- to 19-day-old F344 rats. Despite the absence of sarcomas in the sections examined microscopically from each such liver before digestion and the presence of multiple hepatomas in all sections examined, vascular sarcomas, probably angiosarcomas, were observed in a large proportion of animals injected with the suspensions of cells; hepatomas were not observed in these animals. Morphology by light microscopy, immunohistochemical demonstration of factor VIII, histochemical demonstration of alkaline phosphatase, and the presence of Weibel-Palade bodies strongly suggest that these tumors are angiosarcomas. Similar tumors developed from cells obtained in parallel with the aid of Pronase, collagenase, or trypsin. Cell suspensions obtained with Pronase yielded tumors with the shortest latent period between the injection of cells and the death of one-half of the transplant recipients. The procedure that we used provides a consistent method for the production of transplantable sarcomas. The absence of sarcomas in the single sections taken from donor livers and multiple sections of similar livers not used for transplantation suggests that transplantability of these sarcoma cells is acquired very early in this neoplasm.

Alkaline Phosphatase↗
PubMed1985

Enzyme activities in prostatic carcinoma related to Gleason grades.

In an effort to identify enzymatic activities in primary prostatic carcinomas that might be complementary to histological and other clinical techniques for the prediction of prognosis, we have assayed several enzymatic activities extracted from prostatic carcinomas. We reported previously that, for each of the studied enzymes, tissues with benign prostatic hyperplasia and prostatic carcinoma showed significantly different activities. With additional patients now included and a longer interval since resection of these tumors, we have found that the histological grade (Gleason's system for grading) of the sample (prostate chip) analyzed is related to several activities extracted from the cancers including arginase (r = -0.81, p less than 0.0001), glucose-6-phosphate dehydrogenase (r = 0.72, p less than 0.0001), and the B isoenzyme of N-acetyl-beta-D-glucosaminidase (r = -0.58, p = 0.0369). Acid phosphatase (r = 0.15, p = 0.5530) and the BB isoenzyme of creatine kinase (r = -0.13, p = 0.5221) are not significantly related to histological grade. In a large series, Gleason grade is related to survival. In our series of 27 patients followed for 20 to 46 months, the Gleason grade (p = 0.22) is not related to survival, but arginase activity is related (p = 0.0392) to survival. In this small series, arginase is more valuable than the best currently proven predictor of survival, Gleason grade. Hexosaminidase B activity approaches being significantly (p = 0.0575) related to survival. Of the 11 patients whose tumors contained the lowest arginase activities, eight are dead. Of the 11 with the highest activities, only one is dead. Several of the enzyme activities in this series of 27 patients complemented each other for the prediction of Gleason grade; for example, glucose-6-phosphate dehydrogenase, arginase, and the BB isoenzyme of creatine kinase were more closely correlated (multiple correlation coefficient, r = 0.77) with the Gleason grade for all chips than was any single enzyme: arginase, r = -0.67; glucose-6-phosphate dehydrogenase, r = 0.67; creatine kinase, r = -0.16. It seems likely that enzymatic analysis may provide an approach that is qualitatively different from and complementary to histological evaluation for the prediction of prognosis in prostatic carcinoma. Verification of this hypothesis will require more patients followed over a longer period of time and will probably be facilitated by analysis of several samples from different locations in each tumor.

Acid Phosphatase↗
PubMed1985

Heterogeneity and prognostic significance of macrophages in human colonic carcinomas.

Previously, we reported that high concentrations of eosinophils in human colonic carcinomas are associated with better prognoses, that sections taken 1 cm remote from (deep to) the margin of tumor (SRM) and sections contiguous to the margin (SCM) of tumor and adjacent uninvolved colon contain significantly different concentrations of eosinophils, and that concentrations of eosinophils in SCM and SRM are both useful and complementary for the prediction of prognosis. As a first step towards studying the ecology of the eosinophil in colonic carcinoma and with the goal of identifying other kinds of cells that might be useful for the prediction of prognosis, we counted cells in SCM and SRM that expressed histochemically demonstrable acid phosphatase, alpha-naphthylbutyrate esterase, and peroxidase. The tumors of patients with and without metastases at the time of resection of the primary tumor contained different (P = 0.0314) concentrations of cells with histochemically demonstrable alpha-naphthylbutyrate esterase in SCM but not in SRM. In contiguous 1- to 2-micron sections, morphologically macrophage-like cells with histochemically demonstrable acid phosphatase and cells with histochemically demonstrable alpha-naphthylbutyrate esterase were found to be present in different concentrations both in SCM (P less than 0.01) and in SRM (P less than 0.01); i.e., these phenotypic markers appear to identify different subpopulations of macrophages in tumors. In contrast to our previous study of human pulmonary alveolar macrophages, examination of sections stained sequentially for these phenotypic markers that are commonly used for the identification of macrophages in tumors revealed numerous cells in the same sections that expressed histochemically demonstrable acid phosphatase (red) but not alpha-naphthyl butyrate esterase (brown) and vice versa. Several of these markers promise to be useful and complementary for the prediction of prognosis.

Acid Phosphatase↗
PubMed1984

Heterogeneity and subcompartmentalization in the distribution of eosinophils in human colonic carcinomas.

Previously the authors reported that high concentrations of eosinophils in human colonic carcinomas are associated with better prognoses. They wished to know whether there were stromal subcompartments in these tumors with respect to the distribution of eosinophils. They evaluated concentrations of eosinophils at the margin and deep to the margin. For tumors with sufficient eosinophils to indicate good prognoses, the concentrations of eosinophils at the margins were strikingly lower than the concentrations in the samples remote from the margins. This is the first report that any kind of inflammatory cell is less concentrated in the periphery of a tumor than more centrally. When eosinophil concentrations were subjected to a square-root transformation, the transformed data for patients with and without metastases were different both for tumor from the margin (P = 0.001) and for tumor remote from the margin (P = 0.021).

Aged↗
PubMed1983

Acid phosphatase in prostatic tissue homogenates from patients with benign prostatic hyperplasia and prostatic carcinoma.

Acid phosphatase activity biochemically in the primary tumor of 20 patients with prostatic carcinoma, was studied in an attempt to understand the basis for a correlation or lack of correlation between serum and/or bone marrow acid phosphatase levels and the presence and/or clinical behavior of prostatic carcinoma. The enzyme activity was similarly measured in 19 patients with benign prostatic hyperplasia as controls. On the average, enzyme activities were lower (P less than 0.002) in the tissues from patients with carcinoma. There was no correlation of enzyme activity in tumor with the age of the patient, stage of disease, degree of differentiation of the tumor, or serum acid phosphatase activity.

Acid Phosphatase↗
PubMed1983

Cytologic characterization of pulmonary alveolar macrophages by enzyme histochemistry in plastic.

Quantitative morphometric analyses of macrophages should facilitate a more precise definition of the role of macrophages in neoplastic diseases and inflammatory diseases of lymphoid and hemopoietic tissues. The usefulness of the available phenotypic markers is affected by the extent to which they are expressed by macrophages in tissue sections. For our study of phenotypic markers for macrophages in human tissue sections, we selected lung, since pulmonary alveolar macrophages are more readily identified morphologically in tissue sections than macrophages in most other tissues. In 1-2 micron sections of freshly fixed lung embedded in methacrylate, 89.7% of pulmonary alveolar macrophages had histochemically demonstrable acid phosphatase; 86.2%, nonspecific esterase with naphthol ASD chloroacetate as the substrate; 86.2%, nonspecific esterase with alpha-naphthyl butyrate as the substrate; 80.5%, peroxidase; and 75.8%, iron. With respect to their expression of markers, the observed heterogeneity among pulmonary alveolar macrophages is interesting; this heterogeneity may reflect the degree to which they have been activated, the different periods of time since they arrived in the lung, and differences in their local environments. Except for peroxidase, all examined markers were as well demonstrated when tissues were fixed after storage over liquid nitrogen as when fixation was carried out with fresh tissue. Acid phosphatase and nonspecific esterase with the chloroactetate substrate gave bright colors that would facilitate morphometric analyses. The storage of tissue over liquid nitrogen will be equally satisfactory for the characterization of macrophages with histochemical markers and monoclonal antibodies.

Acid Phosphatase↗
PubMed1983

Purification of cells from livers of carcinogen-treated rats by free-flow electrophoresis.

The tumorigenic roles of specific types of cells that emerge during chemical hepatocarcinogenesis in rats could potentially be determined if the specific types of cells could be purified adequately. Type II cells, defined (J. M. Jacobs, T. P. Pretlow, N. Fausto, A. M. Pitts, and T. G. Pretlow, J. Natl. Cancer Inst., 66: 967-973, 1981) as small, slowly sedimenting cells with histochemically demonstrable gamma-glutamyl transpeptidase, have oval nuclei similar in size to those of lymphocytes. Adult male F344 rats were fed a choline-deficient diet containing 0.05% ethionine for 4 weeks. Liver cells were obtained in suspension by in situ perfusion of collagenase. A two-step process, i.e., sedimentation in an isokinetic gradient followed by free-flow electrophoresis, was used to purify type II cells. We obtained preparations of cells with 32.3 +/- 5.0% (S.D.) type II cells, 13.4 +/- 2.0% erythrocytes, 52.9 +/- 3.3% small nucleated cells, and only 1.4 +/- 0.3% hepatocytes. The small nucleated cells were Kupffer cells and cells smaller than Kupffer cells that included many lymphocytes and unidentified cells similar in size to lymphocytes. Because both the electrophoretic mobilities and the rates of sedimentation of type II cells and hepatocytes are different, there is some advantage to be obtained from the sequential use of these techniques that exploit independent differences in the physical properties of these cells.

Acyltransferases↗
PubMed1983

Eosinophil infiltration of human colonic carcinomas as a prognostic indicator.

In experiments with suspensions of cells from colonic carcinomas, we noted that some colonic carcinomas contain large numbers of eosinophils. We therefore carried out a prospective study with 67 almost consecutive colonic carcinomas in our medical center after optimal fixation and staining for the demonstration of eosinophils. Infiltration of the primary tumor by eosinophils was found to have marked prognostic significance. The proportion (4 of 17 or 23.5%) of carcinomas with more than 30 eosinophils/sq mm that had metastases was significantly less (p = 0.01) than the proportion (31 of 50 or 62.0%) of carcinomas with less than 30 eosinophils/sq mm that had metastases. At 18 months, following the resection of tumor in patients without metastases, all of the patients (9 of 9) with greater than 30 eosinophils/sq mm were alive in contrast to 73.7% (11 of 15) of the patients with less than 30 eosinophils/sq mm. The number of survivors at 18 months for the total population without regard to metastases was significantly greater (p = 0.028) for those with greater than 30 eosinophils/sq mm than for those with less than 30 eosinophils/sq mm. We conclude that the quantitative assessment of eosinophils is one of the most important aspects of the microscopic evaluation of this common human tumor.

Colonic Neoplasms↗