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Biomedical subjects

R F Barth

Publications and source records attributed to R F Barth.

At least 91 records · Page 5Linked to original sources
PubMed1986

Gastrointestinal malformations associated with prune belly syndrome: three cases and a review of the literature.

Prune belly syndrome (PBS), a triad consisting of abdominal musculature hypoplasia, urinary tract malformations, and cryptorchidism, is frequently associated with other congenital malformations. Although it is acknowledged that gastrointestinal (GI) malrotation and mesenteric anomalies are frequent in PBS, other GI anomalies are generally considered to be exceedingly rare. Here we describe 3 autopsy cases with severe malformations of both midgut and hindgut derivatives and review the world literature to evaluate the spectrum of GI malformations associated with this syndrome. The relatively high frequency of distal stenoses and atresias suggests that the anomalous mesenteric attachments may predispose to prenatal volvulus and subsequent anatomic bowel obstruction. Postnatal volvulus is also occasionally observed. Infants with PBS also appear to be at a higher risk for persistence of the common fetal cloaca.

Adult↗
PubMed1985

Giant cell myocarditis.

The present report describes a 45-year-old man with giant cell myocarditis who died of heart failure eight months after the onset of symptoms. On postmortem examination, the heart showed extensive myocardial fibrosis with numerous multinucleated giant cells. The lungs and a series of 20 lymph nodes showed no evidence of granulomatous disease, thereby excluding a diagnosis of sarcoidosis. Circumstantial evidence supports the view that giant cell myocarditis may have an autoimmune origin, and the histopathology suggests that cellular immune mechanisms might have a role in the pathogenesis of this disease. On this basis, it is suggested that cyclosporine, a selective inhibitor of T lymphocyte-mediated immune responses, may be useful for the treatment of this presently fatal disease.

Autoimmune Diseases↗
PubMed1985

Dicesium N-succinimidyl 3-(undecahydro-closo-dodecaboranyldithio)propionate, a novel heterobifunctional boronating agent.

The synthesis of a novel heterobifunctional agent, dicesium N-succinimidyl 3-(undecahydro-closo-dodecaboranyldithio)propionate, is described. This structure contains an active ester component known to react rapidly under very mild conditions with amino groups of proteins, resulting in covalent linkage. With use of this boronating agent, approximately 480 boron atoms have been incorporated per molecule of a polyclonal antibody directed against human thymocytes and 1300 boron atoms per molecule were incorporated into a monoclonal antibody, 17-1A, directed against human colorectal carcinoma cells. Binding of the boronated antibodies to the corresponding target cells was demonstrated by means of membrane immunofluorescence. There was some loss in reactivity, as determined by fluorescent end point titers, but specificity remained unchanged. The data suggest that boronated antibodies potentially could be used to selectively deliver boron-10 to tumor cells in order to achieve their destruction by neutron capture.

Antibodies↗
PubMed1985

Monoclonal antibodies directed against preneoplastic and neoplastic murine mammary lesions.

We have produced a panel of monoclonal antibodies directed against a dimethylbenzanthracene-induced murine mammary tumor. Five rat-mouse hybridomas produced antibodies that bound to some murine mammary tumors, but not to normal renal adherent cells, lymphocytes, 3T3 fibroblasts, red blood cells, or mammary gland. One of these antibodies, designated AMT8, was selected for further evaluation based on its relatively strong reactivity, as determined by immunofluorescence. Indirect immunofluorescent studies on frozen histological tissue sections and quantitative immunofluorescent binding studies on cultured normal and tumor cells revealed that AMT8 was bound to certain murine mammary tumors and their preneoplastic hyperplastic nodules, but not to normal murine organs including normal mammary glands. Two tumors and their hyperplastic alveolar nodule counterparts that contained the antigen recognized by AMT8 did not express functional estrogen and progesterone receptors, indicating that antigen expression was not dependent on functional receptors. The antigen recognized did not cap, was found to modulate slowly, and was reexpressed in the presence of excess AMT8. From these findings, we conclude that AMT8 may prove to be a valuable tool for the study of early mammary tumorigenesis.

Animals↗
PubMed1984

Injection of cells and monoclonal antibodies into mice: comparison of tail vein and retroorbital routes.

Organ distribution and blood concentration profiles were compared following injection of mice with radiolabeled test agents via the lateral tail vein or retroorbital venous sinus. Monoclonal antibodies directed against B16 melanoma of C57BL/6 origin were labeled with iodine-125. Thymocytes from BALB/c mice and B16 melanoma cells were labeled with technetium-99m sodium pertechnetate (Na 99mTcO4). Animals were injected with 5 microCI of iodinated antibody, 5 X 10(5) syngeneic thymocytes, 2.5 X 10(5) melanoma cells, or 10 microCi Na 99mTcO4 in 0.2 ml saline via either route. In non-tumor-bearing C57BL/6 mice radiolabeled monoclonal antibody was found primarily in the gastrointestinal tract, liver, and blood. Na 99mTcO4 localized in the gastrointestinal tract, 99mTc-labeled thymocytes in the spleen and liver, and 99mTc-labeled B16 melanoma cells in the liver and lungs. Pharmacokinetic analysis of blood samples taken 4, 8, and 12 min following injection of the labeled agents suggested that the iodinated antibody had less vascular permeability than Na 99mTcO4 and that thymocytes and B16 melanoma cells were trapped in the pulmonary vasculature as they passed through the lungs. It is noteworthy that no biologically significant differences in organ distribution patterns or blood decay profiles were found between lateral tail vein and retroorbital routes. The data clearly indicate that these routes can be used interchangeably with one another for intravenous injections.

Animals↗
PubMed1983

Antigenic cross-reactivity between human leukemic cells and dinitrophenylated normal leukocytes.

Dinitrofluorobenzene-modified normal human leukocytes (DNP-LK) have been shown to evoke the production of antibodies, which following absorption with erythrocytes and unmodified leukocytes (UN-LK) had residual leukoagglutinating activity against human leukemic cells (HLC). In the present study we observed that rabbit antisera prepared against cell membrane extracts of DNP-modified granulocytes (DNP-GM) or lymphocytes (DNP-LM) were cytotoxic to HLC. By passive hemagglutination, these antisera were specifically reactive with DNP-GM or DNP-LM conjugated to sheep erythrocytes (SRBC) but not with DNP-modified bovine serum albumin (DNP-BSA) or bovine gamma globulin (DNP-BGG) nor with UN-LK, suggesting that the antisera were devoid of anti-DNP antibodies. Rabbit anti-DNP-BSA or anti-DNP-BGG failed to react with DNP-LK, and anti-DNP antibodies in these sera could not be absorbed by DNP-LK, suggesting that DNP groups either were not expressed on the surface of DNP-LK or were not detectable by these methods. These data, together with our recent finding that dinitrophenylation alters the expression of histocompatibility antigens, suggest that neoantigens cross-reactive with HLC antigens are induced by DNP modification of membrane antigens of normal leukocytes, and that the antibodies produced against these DNP-modified cells are directed mainly against the modified protein and not against the DNP moiety per se.

Absorption↗
PubMed1982

Physicochemical studies of dinitrophenylated bovine serum albumin.

The structural changes of bovine serum albumin (BSA) as a function of dinitrophenylation have been studied by disc gel electrophoresis, sedimentation velocity analyses, and circular dichroism. These experiments were designed to understand the molecular bases for the change in immunogenicity and antigenicity of BSA upon dinitrophenylation. Dinitrophenylated BSA tends to aggregate to dimers and higher aggregates. A concomitant large change in electrophoretic mobility was also observed. Circular dichroism studies reveal a large decrease in the alpha-helical structure of the BSA molecule.

Animals↗
PubMed1981

Quantitative assay for lectin-induced cytoagglutination by means of an electronic particle-counting technique.

A method employing an electronic particle-counting technique was used to quantify lectin-induced agglutination of human granulocytes and lymphocytes with either concanavalin A or wheat germ agglutinin. The number and mean volume of single cells and aggregates in the presence of increasing concentrations of lectin were computed from 95% confidence intervals. Agglutination depended on both the number of free cells and the number and size of the cell clusters. Changes in these two variables were mutually independent of one another, and both were simultaneously determined. An index of agglutination that takes the effect of these two variables into account was defined as (formula: see text) VA equals mean volume of cell aggregates, NS equals number of single cells, NA equals number of cell aggregates, VS equals mean volume of single cells, rb equals r at a given lectin concentration, and ra equals r in the absence of lectin. For any combination of lectin and cell type, the agglutination curve, as described by zeta, consisted of two components: a) a flat region in which zeta remained constant with increasing lectin concentrations and b) a region in which zeta increased linearly as a function of the logarithm of lectin concentration. The shapes of these curves offered two parameters for quantitative comparison of agglutinability: 1)threshold concentration, defined as the minimum concentration of lectin (microgram/ml) required to bring about a measurable rise in zeta and 2) the concentration gradient, defined as the change in zeta for an increase of one log unit in the concentration of the lectin in the range beyond the threshold concentration. This method offers a high degree of quantification and provides reliable information that can be meaningfully correlated with cell surface characteristics.

Agglutination↗
PubMed1981

Relationship between concanavalin A-induced agglutinability of murine leukemia cells and their propensity to form heterotypic aggregates with syngeneic lymphoid cells.

The agglutinabilities of the murine leukemia cell lines L1210, P388, and C1498 were determined in the presence of concanavalin A (Con A) by a quantitative cytoagglutination assay. The propensity of these cells to form heterotypic aggregates with normal syngeneic spleen cells, those obtained from mice carrying the respective leukemias in ascitic form, and syngeneic lung cells also were determined. Con A caused agglutination of all five types of leukemia cells and the resulting agglutination patterns had certain characteristics. Threshold concentrations of Con A, below which no significant cytoagglutination occurred, were very low. A steady increase in zeta, a previously defined index of agglutination that simultaneously takes into account the number of free cells and the number and size of the aggregates, was observed with increasing concentrations of Con A until a plateau was reached at 25-50 microgram/ml and this extended over a wide range of lectin concentrations (50-1,000 micrograms/ml). Self-aggregation of leukemia cells was not observed, and their propensity to form heterotypic aggregates with syngeneic lung cells was negligible. However, all leukemia cell lines formed measurable aggregates with spleen cells from both normal and leukemia-bearing mice; these aggregates usually reached a maximum plateau between 30 and 35 minutes of incubation and remained constant thereafter. Aggregation of leukemia cells with spleen cells from leukemic mice always was greater than that with spleen cells from normal mice. Con A agglutinability of leukemia cells was correlated with their propensity to form heterotypic aggregates, which suggests that Con A agglutinability of leukemia cells was correlated with their propensity to form heterotypic aggregates, which suggests that Con A receptor carbohydrate moieties may be involved in the intercellular adhesion leading to heterotypic aggregate formation.

Agglutination↗
PubMed1979

Specific and nonspecific cytotoxicity of leukocytes from human renal allograft recipients against donor fibroblasts.

A microcytotoxicity assay was used to search for cell-mediated cytotoxicity, serum-blocking factors, and antibody-dependent cell-mediated cytotoxicity (ADCC) against fibroblasts of donor origin in 19 human renal allograft recipients. Peripheral mononuclear cells (PMC) were frequently cytotoxic when they were obtained within 6 days prior to rejection, following sustained rejections, and within 1 month after removal of rejected grafts, but the toxicity was usually nonspecific. Recipient PMC were noncytotoxic when they were obtained within 6 days after the onset of an acute reversed rejection and during quiescent intervals when there was no evidence of rejection within 6 days before or after the assay. These data suggest that, regardless of its lack of specificity, there is some relationship between cytotoxicity of recipient PMC and allograft rejection. In none of 69 post-transplant serum samples was ADCC against donor target cells detected with the microcytotoxicity assay.

Cytotoxicity Tests, Immunologic↗