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J A Roth

Publications and source records attributed to J A Roth.

At least 433 records · Page 24Linked to original sources
PubMed1986

Variation of neutrophil function with age in calves.

Neutrophil function was evaluated on 2 occasions in 5 calves from each of the following age groups: 4 to 5 weeks, 9 to 11 weeks, 16 to 19 weeks, and 12 to 14 months. Of the neutrophil functions examined, the iodination reaction, which evaluates the activity of the myeloperoxidase-hydrogen peroxide-halide antibacterial system of the neutrophil, reflected the most marked differences among age groups. The iodination values for the 2 youngest age groups were approximately 52% of the value for the oldest cattle. This difference could not be attributed to the amount of myeloperoxidase in the neutrophil granules. Antibody-dependent cell-mediated cytotoxicity also tended to be lower in neutrophils from the 3 younger age groups. Nitroblue tetrazolium reduction, a measure of superoxide anion generation by neutrophils, was lower in the youngest age group only. The capability of neutrophils to ingest Staphylococcus aureus was higher in the 3 youngest groups of calves than in the oldest group. The observed differences in neutrophil function in young vs older calves may be partially responsible for the increased susceptibility of young calves to infectious disease.

Aging↗
PubMed1985

Effect of phosphatase inhibition of in vitro dopamine sulfation and 3'-phosphoadenosine-5'-phosphosulfate catabolism in human brain.

The effects of inhibition of phosphatase activity in 100,000 g supernatant solution from human frontal cortex on dopamine (DA) conjugation were examined using the phosphatase substrate p-nitrophenyl phosphate (pNPO4). The increases in DA sulfation seen in the presence of pNPO4 suggested that inhibition of phosphatase activity in high speed supernatant solutions of brain may substantially alter the pattern of 3'-phosphoadenosine-5'-phosphosulfate (PAPS) metabolism and subsequently the rate of DA sulfation. Accordingly, the effects of the pyrophosphate analog phosphonoacetic acid (PAA) on the extent of DA sulfation and PAPS metabolism were examined in 100,000 g supernatant solution from human frontal cortex. At concentrations up to 10 mM, PAA markedly reduced PAPS hydrolysis to inorganic sulfate and 3'-phosphoadenosine-5'-phosphate (PAP) and significantly extended the linear time period for the sulfation of DA. These findings suggest that the phosphatase enzymes that degrade PAPS to produce the end product inhibitor, PAP, and possibly other break-down products of PAP, play an important role in determining the observed levels of phenol sulfotransferase activity in tissue from human brain in vitro.

Adenine Nucleotides↗
PubMed1985

Immunostaining for carcinoembryonic antigen does not discriminate for early recurrence in breast cancer. The ECOG experience.

Carcinoembryonic antigen (CEA) immunohistochemistry was evaluated by 11 surgical pathologists with sections from 147 postmenopausal women with node-positive breast cancer. Carcinoembryonic antigen staining in breast cancer tissues has been correlated with a worse prognosis. This association was studied with a clinically characterized population of Eastern Cooperative Oncology Group (ECOG) patients using precisely the peroxidase-antiperoxidase methodology which had been employed in another published study. In 50% of the cases, the study pathologists were uncertain whether CEA was or was not present in the cancers. Various groupings of the pathologists' interpretation were compared with the observed disease-free intervals in the patients. These analyses suggested no association of perceived CEA staining with the biological course of the cancers. Two reference pathologists who examined the sections in a similar way also gave non-prognostic interpretations. There is no convincing evidence that pathologists can reliably interpret the CEA content in the same breast cancer tissue sections. There is no observed correlation between immunohistochemical evidence of CEA in a breast cancer tissue section and the biological behavior of that cancer.

Aged↗
PubMed1985

A modified Ecteola cellulose assay for M and P phenol sulfotransferase.

The development and applications of a modified Ecteola cellulose, ion exchange assay for phenol sulfotransferase (EC 2.8.2.1, PST) are described. Mixtures containing dopamine or phenol and 35S-labeled 3'-phosphoadenosine-5'-phosphosulfate (PAPS) were incubated with 100,000 g supernatant solution from human frontal cortex and applied to 0.5 X 2 cm columns of Ecteola cellulose. Dopamine sulfate was eluted with 3 ml of distilled water, while phenyl sulfate, inorganic sulfate and unreacted PAPS were eluted with successive step gradients of 5, 20 and 200 mM NH4HCO3. The solution volume for phenyl sulfate was 11 ml, while those for inorganic sulfate and PAPS were both 6 ml. The new assay method yielded apparent Km values for dopamine, 3-methoxytyramine, tyramine and norepinephrine similar to those obtained by other methods. Comparison of the activities of various amine substrates at a concentration of 20 microM showed that dopamine was the preferred substrate, followed in decreasing order of relative activity by 3-methoxytyramine, norepinephrine, tyramine and octopamine. When mixed substrate inhibition of dopamine sulfation by phenol was examined, phenol was found to effectively inhibit dopamine sulfation over a range of 0.1 to 10 mM. The procedure described in this paper offers a number of significant advantages over currently available assays: these include a rapid, simple product isolation procedure and a complete, discrete separation of the radiolabeled products and reactants. This property allows the detailed study of the flux of radiolabel through the enzymatic system and also makes alternative substrate inhibition studies possible.

Arylsulfotransferase↗
PubMed1985

Cellular localization of MAO A and B in brain: evidence from kainic acid lesions in striatum.

The cellular localization of the two forms of monoamine oxidase (MAO A and MAO B) was studied by measuring their activities in rat striatum following unilateral stereotaxic injection of kainic acid to produce selective degeneration of striatal neurons and subsequent proliferation of astrocytes. The results demonstrated a persistent loss of 15-20% in MAO A activity, whereas MAO B activity decreased initially by 25% and then increased to more than twice the control value by 54 days after lesions. The changes in activity were compared to parallel estimates of the postsynaptic neuronal enzyme markers glutamic acid decarboxylase (GAD) and neuron-specific enolase (NSE), astroglial enzyme markers glutamine synthetase (GS) and non-neuronal enolase (NNE), and the presynaptic enzyme marker DOPA decarboxylase (DDC). The results suggest that a small amount of striatal MAO A is present in kainic acid-sensitive postsynaptic striatal neurons and that MAO B is probably localized in both neurons and astrocytes.

Animals↗
PubMed1985

Purification and kinetic characterization of a dopamine-sulfating form of phenol sulfotransferase from human brain.

The kinetic and biochemical properties of a purified, monoamine-sulfating form of phenol sulfotransferase (M-PST) from human brain are described. M-PST activity was separated and purified from phenol-sulfating activity by anion-exchange chromatography on DEAE-cellulose and subsequently purified on AffiGel Blue and Sephacryl S-200, routinely giving a final purification of over 20 000-fold, with approximately a 3% yield. The molecular weight of the active species, as estimated by gel filtration chromatography, was 250 000. The purified enzyme was inhibited by NaCl (50% at 325 mM) and showed an optimum for dopamine sulfation at pH 7.0. Of the monoamine substrates examined, 4-methoxytyramine was the most extensively sulfated at 20 microM, while at higher substrate concentrations (200 microM), tyramine was the apparent preferred substrate. Kinetic analysis demonstrated that sulfation by M-PST proceeds via an ordered, bisubstrate reaction mechanism, where 3'-phosphoadenosine 5'-phosphosulfate (PAPS) is the leading substrate. True Km values for dopamine and PAPS were 2.9 and 0.35 microM, respectively. The product inhibitor 3'-phosphoadenosine 5'-phosphate possessed a Ki of 0.07 microM, while the dead-end inhibitor ATP exhibited a Ki of 170 microM.

Adenosine Triphosphate↗
PubMed1985

Human brain monoamine oxidase type B: mechanism of deamination as probed by steady-state methods.

Recently, evidence has been published which suggests that [Husain, M., Edmondson, D. E., & Singer, T.P. (1982) Biochemistry 21, 595-600] monoamine oxidase [amine:oxygen oxidoreductase (MAO), EC 1.4.3.4] deaminates phenylethylamine and benzylamine via two distinct kinetic pathways which involve either binary or ternary complex formation, respectively. These conclusions were drawn largely from stopped-flow kinetic analysis performed on purified enzyme removed from its native membrane and in the presence of the inhibitory detergent Triton X-100. In this study, d-amphetamine and alternative substrates were used as steady-state probes of the kinetics of deamination by the B form of human brain MAO using native membrane-bound enzyme. Initial velocity studies showed mixed-type patterns for amphetamine inhibition of phenylethylamine, tryptamine, and tyramine when either amine or oxygen was the varied substrate. Slope and intercept vs. amphetamine concentration replots were linear in all cases except for phenylethylamine (hyperbolic); Ki values obtained from linear replots of slope or intercept values were comparable. In contrast, amphetamine was a competitive inhibitor of benzylamine deamination when amine concentration was varied and uncompetitive when oxygen concentration was varied; slope and intercept replots were linear for both. When benzylamine was the alternative substrate inhibitor and tyramine and tryptamine deamination was measured, mixed-type inhibition patterns were obtained when either amine or oxygen concentration was varied; replots of slope and intercept were linear in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain↗
PubMed1985

Differing determinants of prognosis following resection of pulmonary metastases from osteogenic and soft tissue sarcoma patients.

A study was performed to determine if prognostic factors could be used preoperatively to predict outcome following resection of metastases. Sixty-seven soft tissue sarcoma (STS) patients (median follow-up, 36 months) and 39 osteogenic sarcoma patients (OGS) (median follow-up, 29 months) underwent thoracic exploration at the first indication of pulmonary metastases, and the results for each group were reviewed. The number of metastatic nodules, disease-free interval (DFI), and tumor doubling time (TDT) significantly correlated with postoperative survival for STS patients. Patients with four or fewer nodules on preoperative linear tomograms survived longer (median, 23 months) than patients with more than four nodules (median, 6 months; P less than 0.005). Patients with a DFI greater than 12 months had a longer survival (median, 30 months) than patients with a DFI less than or equal to 12 months (median, 10 months; P less than 0.005). Patients with a TDT greater than or equal to 20 days had a longer survival (median, 22 months) than patients with a TDT less than 20 days (median, 6 months; P less than 0.005). The only significant predictor of survival for OGS patients was the number of nodules on preoperative linear tomograms (less than or equal to 4, 37 months median survival; greater than 4, 10 months median survival; P less than 0.05). This was due to significant differences noted for the DFI and TDT distributions between OGS and STS patients, with most OGS patients having a short DFI (less than or equal to 12 months) and a rapid TDT (less than or equal to 20 days) whereas STS patients had a more heterogeneous distribution (P less than 0.01). Thus, the number of metastases visible on the preoperative tomogram was the best predictor of survival for both OGS and STS patients. However, the applicability of other prognostic factors could not be generalized for these two closely related groups of patients.

Adolescent↗
PubMed1985

Activation of neutrophils by antigen-induced lymphokine, with emphasis on antibody-independent cytotoxicity.

Incubation of bovine neutrophils with antigen-stimulated mononuclear cell supernatant (lymphokine) caused an inhibition of neutrophil migration and an enhancement of the neutrophils' ability to adhere to plastic, reduce nitroblue tetrazolium, ingest Staphylococcus aureus, and mediate antibody-dependent cell-mediated cytotoxicity (ADCC) against chicken erythrocytes. Lymphokine-treated neutrophils also became cytotoxic for chicken, turkey and human erythrocytes in the absence of specific antibody but were not cytotoxic for bovine erythrocytes. The increase in antibody-independent neutrophil cytotoxicity (AINC) was not due to direct cytotoxic activity of the lymphokine or to a stable, soluble mediator released by the neutrophils. Enhancement of AINC, but not ADCC, required RNA and protein synthesis by the neutrophil. These results indicate that several aspects of neutrophil function can be altered by products secreted by antigen-stimulated mononuclear cells and that neutrophils can be induced to recognize and to have increased cytotoxic activity toward heterologous erythrocytes.

Animals↗
PubMed1985

Identification and characterization of a tumor-derived immunosuppressive glycoprotein from murine melanoma K-1735.

A suppressive immunoregulatory factor (IRF) produced by murine melanoma K-1735 M3 has been identified. Extracts from tissue or cultured cells grown in serum-medium were prepared by 3 M KCl extraction and partially purified by low-salt precipitation. IRF extracted from fresh tumor, cultured cells, and spent medium from the K-1735 cell line suppressed 3H-thymidine incorporation by splenocytes during mitogen stimulation. Cell viability was not impaired by IRF. IRF suppressed splenocyte proliferation, protein synthesis, murine IL-2-mediated blastogenesis, and mixed splenocyte responses. However, in vitro generation of allogenic cytotoxic cells was not suppressed. Significant inhibitory activity could not be extracted from normal tissues. IRF activity was reduced by treatment with proteolytic enzymes and neuraminidase and was bound by lentil lectin, indicating that the factor is a glycoprotein. IRF was heat-stable, yet labile to treatment with acid, base, or 2-mercaptoethanol. Inhibitory activity was partially characterized by preparative isoelectric focusing (pI 3.5-5.8), and the active moiety had a molecular size of 10-12 K according to HPLC. The HPLC-purified active fraction of IRF did not contain the immunosuppressive retroviral antigen p15(E). Splenocytes from animals treated with IRF in vivo demonstrated reduced responses to Con A and PHA in vitro. Suppressor cells were not identified. We have identified a low-molecular-weight glycoprotein from a murine melanoma, which suppresses a variety of immunologic responses in vitro and in vivo. IRF appears to be a potent mediator of tumor-induced immunosuppression in this model.

Animals↗
PubMed1985

Interobserver reproducibility of histopathological features in stage II breast cancer. An ECOG study.

Eleven surgical pathologists studied microscopic sections from 45 mastectomy specimens of node positive breast cancer patients who had been entered into ECOG clinical trials. Inter-observer reproducibility for histoprognostic features was examined as a prerequisite before a subsequent evaluation of their possible clinical applicability could be undertaken. Histological type, nuclear grade, tubular formation, and lymphoid reactions were studied in the cancerous tissues. Lymph nodal responses (follicular and pulp prominence, sinus histiocytosis) were also examined in a manner that stimulated slide review in routine surgical pathology practice. Numerous two-way comparisons of the pathologists' findings resulted in low levels of agreement (usually much less than 90%). The degree of inter-observer reliability is clinically unacceptable using customary slide review analysis. New ways of examining breast cancer tissues need to be explored in the search for prognostic features which can be applied to the clinical management of breast cancer patients.

Breast Neoplasms↗
PubMed1985

Detection of a surface antigen on NIH3T3 cells transfected with a human leukemia oncogene.

This study was conducted to examine the cell surface changes associated with oncogene induced transformation. Using the transfection technique the DNA of a human acute lymphocytic leukemia (ALL) was used to transform murine NIH3T3 cells. Balb/c mice were immunized with these transfectants and their immune splenocytes were used to produce a monoclonal antibody (17-9H3). Antibody 17-9H3 was demonstrated to bind to the cell membranes of transfectants and leukemia cells but not normal 3T3 cells in an enzyme linked immunosorbent assay. Fresh human leukemias, cultured leukemia lines and normal hemopoietic cells were examined with immunoperoxidase staining techniques to determine the specificity of 17-9H3. Our data suggest that the antigen associated with a human acute lymphocytic leukemia oncogene is ubiquitous, distributed among both neoplastic and normal hemopoietic cells. Among fresh human leukemias the antigen appears to be present primarily on fresh null ALLs and chronic myelogenous leukemia (CML) in blast crisis. This antigen was also found to be expressed by the majority of cultured T-cell lines tested.

Animals↗
PubMed1985

Suppression of murine immunologic functions by fresh and cultured human tumor extracts.

The role of human tumor-derived immunoregulatory factors (IRF) in the suppression of murine in vitro cell-mediated immune systems was investigated. IRF was extracted from a fresh human colon carcinoma and a liposarcoma using 3 M KCl. These extracts have previously been shown to suppress in vitro human immune responses. Both IRF extracts inhibited PHA-stimulated murine splenocyte [3H]Tdr uptake in a dose-dependent manner while extracts of normal tissue were not inhibitory. To further investigate in vitro immunosuppression a (C57BL/6 X A/J) F1 anti-B10. BR mixed lymphocyte reaction (MLR) was developed. Optimal [3H]Tdr incorporation was on Day 4 with 1 X 10(5) responders and 2 X 10(5) irradiated stimulators. Addition of IRF caused a 56% inhibition of this response but did not alter the kinetics of the MLR response. Induction of cell-mediated cytotoxicity (C57BL/6 X A/J F1 vs B10.D2) was significantly inhibited by addition of IRF during in vitro sensitization. Release of 51Cr from P-815 targets was decreased to spontaneous release levels at an effector:target (E:T) ratio of 20:1 when IRF was present during sensitization. At this E:T ratio, cells sensitized in the presence of a normal muscle 3 M KCl extract or medium caused 71 and 60% 51Cr release, respectively. IRF activity could also reproducibly be extracted from two small cell lung carcinoma tissue culture lines grown under a variety of culture conditions or passaged in nu/nu mice. The biochemical characteristics of the factor inhibiting human and murine lymphoid cell proliferation were identical. Thus, this system provides a convenient model for assessing the activity of human tumor-derived immunoregulatory factors.

Animals↗
PubMed1985

Expression of a murine B16 melanoma-associated antigen analyzed by flow cytometry.

Understanding factors regulating expression of tumor antigens is vital to the design of rational immunotherapeutic strategies. A murine monoclonal antibody (MM2-3C6) that recognizes a B16 murine melanoma-associated membrane antigen was used to study antigen expression in relation to cell cycle, clonal heterogeneity, and growth density. Dual-parameter flow cytometric measurements of DNA content and membrane antigen demonstrated that antigen-positive cells were found throughout the cell cycle. However, some antigen-negative cells were observed and were restricted to the G0/G1 phase demonstrating the antigenic heterogeneity of this tumor line. Three sublines of B16, F1, F10, and F1r with variable metastatic potential, and 50 B16 F1 clones all expressed the antigen with a mean antigen density above background of 8.84 +/- 2.52 [( mean cell fluorescence/cell size] X 10(-3] ranging from 3.68 to 16.57. Further studies of three sublines and five clones showed antigen density fluctuated over an 8-day growth period in culture with daily changes of medium. During log growth from Day 1 (1.2 +/- 0.08 X 10(4) cells/cm2) to Day 4 (20.4 +/- 3.01 X 10(4) cells/cm2), antigen density increased from 4.09 +/- 0.29 to 6.86 +/- 0.29. By Day 8 (26.5 +/- 2.86 X 10(4) cells/cm2) when the cells had been confluent for 3 days, antigen density decreased to 2.54 +/- 0.26 which was significantly lower than other days measured (P less than 0.05). It is concluded that tumor cell proliferation and cell density can modulate antigen expression in this system and, therefore, this may be a useful model to study tumor cell escape from immunotherapy.

Animals↗
PubMed1985

Evaluation of noninvasive tests for the preoperative staging of carcinoma of the esophagus: a prospective study.

A prospective study was undertaken to define the usefulness of conventional full-lung linear tomography, radionuclide liver plus spleen and bone scans, and thoracic and abdominal computed tomography for the preoperative staging of carcinoma of the esophagus. Thirty-three patients with carcinoma of the esophagus were studied. The computed tomographic (CT) scan of the thorax and upper abdomen was the single most accurate noninvasive study. With computed tomography, the relationship of the tumor to the tracheobronchial tree was the feature most useful in predicting local resectability. In all patients with the finding of tracheobronchial compression by the tumor, the tumor could not be resected completely. The predictive value of this CT finding in patients with locally unresectable tumor was high (0.83), indicating its usefulness in assessing unresectability. The CT finding of visible separation between tumor mass and tracheobronchial tree was present in 10 of 14 patients with locally resectable tumor (predictive value, 0.63). However, tumor abutting the tracheobronchial tree without compression was a poor predictor of unresectability (predictive value, 0.36). The radionuclide bone scan was the only other noninvasive study to demonstrate a metastasis not evident by CT scan. The combination of chest and abdominal CT scan, bone scan, and bronchoscopy before operation will accurately stage the majority of patients with esophageal cancer but no noninvasive test is of sufficient reliability to exclude patients from operative resection if otherwise indicated.

Adenocarcinoma↗
PubMed1985

Isolation of components of Brucella abortus responsible for inhibition of function in bovine neutrophils.

The effects of fractions of Brucella abortus strain 2308 on functions of bovine polymorphonuclear neutrophils (PMNs) were examined in vitro. Ingestion of Staphylococcus aureus and reduction of nitroblue tetrazolium dye by bovine PMNs were not inhibited by heat-killed B. abortus. The ability of PMNs to iodinate proteins was significantly inhibited by live or heat-killed B. abortus and supernatant from heat-killed cells but not by washed heat-killed cells. Two inhibitory components isolated from the supernatant by high-performance liquid chromatography were characterized as nucleotide-like substances with molecular weights of less than 1,000. Inhibition of iodination by these components was concentration dependent. These results indicate that one of the mechanisms by which B. abortus may escape intracellular killing by PMNs is through the production of low-molecular-weight components that inhibit the myeloperoxidase-hydrogen peroxide-halide antibacterial system of bovine PMNs.

Animals↗
PubMed1985

Purification and kinetic mechanism of human brain soluble catechol-O-methyltransferase.

The soluble form of human brain catechol-O-methyltransferase (EC 2.1.1.6, COMT) has been purified approximately 4,000-fold from a 250,000 X g supernatant solution. The purified enzyme exhibits a molecular weight near 27,500 and a pI value equal to approximately pH 5.0. Initial velocity and product inhibition studies are consistent with an ordered reaction mechanism for soluble COMT. Tropolone, a dead-end inhibitor, exhibited a competitive pattern of inhibition when dopamine (DA) was the varied substrate and an uncompetitive pattern when S-adenosyl-L-methionine (SAM) was the varied substrate. These observations strongly suggest that the soluble form of COMT from human brain catalyzes the O-methylation of catecholamines via an ordered reaction mechanism in which SAM is the leading substrate. Since the membrane-bound form of COMT catalyzes the O-methylation of catecholamines through an identical reaction mechanism, these data provide further evidence that two forms of COMT, while being localized in distinct subcellular compartments, are quite similar in their molecular structure.

Brain↗