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J W Paul

Publications and source records attributed to J W Paul.

14 recordsLinked to original sources
PubMed1992

1,1,3 Tricyano-2-amino-1-propene (Triap) stimulates choline acetyltransferase activity in vitro and in vivo.

1,1,3 Tricyano-2-amino-1-propene (Triap) is a small molecule that has neurotrophic properties similar to nerve growth factor (NGF). Studies have shown that NGF increases choline acetyltransferase (ChAT) activity, the enzyme responsible for the synthesis of acetylcholine, in several cell lines and in the CNS of adult animals. To investigate whether Triap can cause similar increases in ChAT enzyme activity, we used the PC12 cell line and primary cultures of rat fetal brain tissue to examine Triap's effects. Nanomolar concentrations of Triap produced a 4.2- and 2.1-fold increase in the ChAT activity of PC12 cells and cultured rat fetal brain cells, respectively. This stimulation reached a plateau within 4 days of treatment in the primary fetal brain cultures with the first increases evident within 24 h. In the PC12 cell line, Triap's stimulation of ChAT activity was significantly greater than increases produced by optimal concentrations of NGF. Triap also matched NGF's stimulation of ChAT activity in primary neuronal culture. Triap also potentiated NGF's actions on ChAT activity in the PC12 cell line and in primary fetal neuronal cultures. These increases in enzyme activity correlated with increases in cellular enzyme levels as assessed using immunochemical identification of the ChAT enzyme. We also conducted experiments to determine if Triap also induced these same increases in ChAT activity in adult animals. Ten-day chronic injections of Triap in mice resulted in significant increases in specific ChAT enzyme activity in the cortex and septal-hippocampal area. Similar increases in ChAT enzyme levels were also detected using western blotting techniques.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

1,1,3 tricyano-2-amino-1-propene (Triap): a small molecule which mimics or potentiates nerve growth factor.

1,1,3 Tricyano-2-amino-1-propene (Triap) is a small molecular weight compound which increases the rate of nerve and tissue regeneration in several experimental systems. Early experiments with this compound showed that, like nerve growth factor (NGF), Triap induced neurite formation in chick spinal ganglia. To assess the similarity between NGF and Triap, we compared the effects of Triap and NGF on a rat pheochromocytoma cell line (PC12) and on cell survival in a primary chick neuronal culture. In the latter, Triap at less than 0.01 nM preserved neurons and caused them to extend neurites as did 1 nM NGF. Triap induced neurite outgrowth in the PC12 cell line giving a maximal response (40-50% of the maximal response of NGF) at a concentration of 20 micrograms/ml (151 microM). Triap's morphological effects were not inhibited by antibodies directed against NGF or the NGF receptor. Low concentrations of Triap also potentiated the morphological effects of NGF. Triap induced an increase in cell-substratum adhesion and cellular hypertrophy in PC12 cells and also potentiated the adhesive actions of NGF. Triap had no effect on ornithine decarboxylase activity even though it potentiated NGF's effects on this enzyme. These data indicate that Triap induces neurotrophic effects and does not seem to act through the same mechanisms as NGF but can potentiate many of NGF's morphological and biochemical actions.

Animals↗
PubMed1988

Induction by cells of immune responses to intestinal epithelial cell-associated components (ECAC): transfer with cultured murine mesenteric and popliteal/axillary lymph node cells.

Although systemic and mucosal immune responses to intestinal epithelial self-antigens occur in several human disorders, there is no model system with which to study the physiology and regulation of the underlying cellular events. Therefore, we undertook to induce an immune response to purified epithelial macromolecules in the Lewis rat; characterize in vitro the reactive cells; and then transfer with immunocytes this antiepithelial reactivity to naive syngeneic rats, identifying the fine specificity and site of humoral and cell-mediated immunity induced in the cell recipient. Donor animals sensitized systemically (via footpad) or locally in gut mucosa (via Peyer's patches) to syngeneic or xenogeneic epithelial antigens generated specific immunoglobulin and were found to have T lymphocytes in the draining nodal areas (including the mesenteric nodes) which were (a) antigen-specific, having a [3H]thymidine uptake in the presence of antigen 30-fold the control; (b) generally of the Thelper/inducer subclass (W3/25+) which, upon further culture, developed phenotype surface markers for activation (IL-2R+); (c) able to induce an antigen-specific humoral and cell-mediated responses upon intravenous injection into naive syngeneic hosts; and (d) demonstrable in gut-associated lymphoid tissue (mesenteric lymph nodes) and, to a lesser extent in spleen, of the cell recipient. Further, lymphocytes cloned from reactive mesenteric lymph node cells demonstrated specificity for a gel-purified subfraction of epithelial antigen, designated P1, containing highly conserved organ-specific macromolecules thought to be autoantigenic for gut.

Animals↗
PubMed1988

Sensitization to epithelial antigens in chronic mucosal inflammatory disease: immunochemical similarity of macromolecules in human colonic epithelium with murine intestinal epithelial cell-associated components (ECAC).

In order to explore whether human intestinal epithelium contains cell-associated components that are organ-specific and therefore potentially autoantigenic, macromolecules were isolated in aqueous-soluble form from histologically normal human colonic epithelial cells, partially purified under nondenaturing conditions, then characterized biochemically and immunologically. Preparative non-SDS-polyacrylamide gel electrophoresis followed by electro-elution into a Tris-glycine buffer separated five human colonic fractions (yield 86%), all of which possessed an acidic isoelectric point (4.0-4.8) and a modest carbohydrate content (0.9-15%), resembling fractions of corresponding Rf similarly prepared from murine colonic epithelial cells. Immunological characterization suggested that two of the gel-purified fractions (B1, B2) isolated from colonic epithelium contained organ-specific determinants: (i) reactivity of B1/B2-specific immunoglobulin was not diminished by prior absorption with proteins from other epithelial surfaces (tracheal mucosal components) nor from normal serum; (ii) epitopes on ECAC B1 and B2 fractions were shared across species lines, with reactivity for the cross-reactive determinant being as much as 20-fold that of control protein; and (iii) localization studies with specific antibody showed an organ- and cell-restricted immunofluorescence pattern on freshly fixed human and murine mucosal epithelial tissue, using B1-specific monoclonal antibody. Given the reported binding of inflammatory bowel disease serum immunoglobulin and lamina propria mononuclear cells for murine ECAC determinants, our studies suggest these same antigens are present in human colonic epithelium, and are available as potential binding sites for antibody or lymphocytes participating in an autoaggressive immune response.

Animals↗
PubMed1987

Sensitization to epithelial antigens in chronic mucosal inflammatory disease. III. Serum factor modulates circulating and mucosal mononuclear-cell reactivity to epithelial cell-associated components of colon (ECAC-C).

A prior report indicated that sera together with peripheral blood mononuclear cells from patients with Crohn's disease were reactive with epithelial cell-associated components derived from small bowel (ECAC-SB). In the present study, we sought to determine whether similar components (designated ECAC-C) from everted, inflated loops of murine colon could be purified to homogeneity in aqueous soluble form and physiochemically characterized; if sera and/or peripheral mononuclear cells from patients with a chronic idiopathic inflammatory disorder of intestinal mucosa were specifically reactive with ECAC-C; whether immunoglobulin was the factor conferring specificity to the anti-ECAC-C response; and if this immunoglobulin was actively synthesized by human lamina propria B lymphocytes isolated from disease-involved intestinal mucosa. Preparative polyacrylamide gel electrophoresis followed by elution of specific bands resulted in the isolation of three major proteins in homogeneous form. Each was a distinctive macromolecule by molecular weight (39,000, 63,000, 148,000), carbohydrate/protein content, and serologically detectable determinants as assessed by quantitative hemagglutination inhibition. By a 51Cr release microcytotoxicity assay, ECAC-C-labeled indicator cells were specifically lysed by sera and peripheral blood mononuclear cells from patients with ulcerative colitis (8.0 +/- 6.8%) and Crohn's disease (13.2 +/- 4.7%), compared with age-/sex-matched controls (0.6 +/- 0.9 and 0.2 +/- 0.4%, respectively). That the factor conferring ECAC-C specificity was immunoglobulin was demonstrated by the retention of ECAC-C-specific reactivity of patient sera in the presence of normal peripheral blood mononuclear cells, the ability of patient sera (without cells) to effect complement-mediated lysis against erythrocytes labeled with ECAC-C (8.0 +/- 6.7%) but not with control kidney antigen (0.7 +/- 0.7%), and the fact that purified immunoglobulin from patient sera could substitute for the latter in an ECAC-C-specific antibody-dependent cellular cytotoxicity assay. Unique aspects of this ECAC-C reactivity included its absence from sera in other disorders with a known or presumed autoimmune basis (systemic lupus erythematosus, chronic active hepatitis) and the lack of simultaneous reactivity directed toward control antigens, isolated from kidney in a manner analogous to that used for ECAC-C. The importance of ECAC-C-specific immune responses at the mucosal level was also examined using mononuclear cells isolated from disease and control intestinal lamina propria (LPMC).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1987

Drug interactions and incompatibilities.

The clinical significance of drug interactions in animals is often minor, but, in some cases, they may result in a fatal outcome. In the critically ill patient, the temptation to employ relatively large doses, particularly of antimicrobials or corticosteroids, or to use multiple-drug therapy is enhanced. These two factors, combined with a debilitated state of the patient, increase the probability of severe drug interactions that could mean the difference between recovery or death. It would be prudent to consider the possibility of drug interactions when selecting drugs for concomitant use, evaluating adverse reactions, evaluating laboratory test results, or mixing drugs in vitro.

Animals↗
PubMed1987

Antigen-specific messenger RNA for immunological research: purification and characterization of RNA from intestinal epithelial cells using specific antibody.

A murine organ-specific antigen system (ECAC B1,B2) has been described that is reactive with sera and lymphocytes from patients with chronic inflammatory bowel disease. However, the amino acid sequence of macromolecules comprising ECAC is unknown, making difficult synthesis of a genetic (DNA) probe for molecular biologic studies. As an alternative to obtain a specific cDNA clone, we developed a methodology to immuno-purify and characterize ECAC-specific messenger RNA from murine and human gut mucosal epithelium. Advantages of this new approach include that it is rapid, non-radioactive, applicable to heterologous or monoclonal immunoglobulin, and of low cost. 100 X 10(6) intestinal epithelial cells were lysed with 0.35% V/V NP-40, and the supernatant layered on a 65% W/V sucrose solution for isolation of polyribosomes by ultracentrifugation. ECAC B1/B2-specific mRNA was isolated from this polyribosome fraction using protein A column-purified specific immunoglobulin from heterologous hyperimmune serum or from monoclonal ascites, followed by adsorption of antibody-bound polyribosomes on a solid phase composed of Sepharose-protein A. After messenger RNA elution, the poly-adenine-containing fraction was further purified by oligo-dT chromatography and characterized. The yield of highly purified messenger RNA (A260/A280 greater than or equal to 2) was 10-20 micrograms/10(8) epithelial cells, and formaldehyde agarose gel electrophoresis demonstrated a limited number of RNA bands had been isolated (150-1400 base-pairs in size). The function of murine and human (normal and disease-involved) messenger RNA isolates was determined in a cell-free in vitro translation system, demonstrating synthesis of single components of ECAC identified by immunoblotting, enzyme-linked immuno-sorbent assay, and analytical polyacrylamide gel electrophoresis of lysate fractions after immuno-affinity chromatography. We conclude that heterologous or monoclonal antibody can be used to isolate antigen-specific messenger RNA from a species other than that from which the antigen was originally isolated, that the functional status for translation of newly purified mRNA can be easily determined by one of several non-radioactive means, and that the technique can be applied even to cells with a high enzymatic degradative capacity, such as those in gut epithelium.

Animals↗
PubMed1984

Safety of fenbendazole use in cattle.

Fenbendazole (Panacur: Hoechst) has a low degree of toxicity, teratogenicity and adverse effects on the reproductive tract, and a high degree of safety in experimental animals. Acute, subacute and long-term toxicity trials in cattle given fenbendazole at dosages of up to 2 g/kg revealed no adverse effects. Studies of teratogenicity, effects on fertility, compatibility with other drugs, and safety for animal handlers had similarly negative results.

Abnormalities, Drug-Induced↗