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Biomedical subjects

J M Oliver

Publications and source records attributed to J M Oliver.

At least 91 records · Page 5Linked to original sources
PubMed1988

Client characteristics as determinants of intervention modality and therapy progress.

The relationship between client characteristics and assignment to family or individual therapy and therapy progress was examined in 131 child cases. Assignment to family therapy was related to help-seeking variables, suggesting that the recommendation followed a therapeutic rationale. History of prior services and client's race were both associated with levels of progress, with results indicating benefits from previous therapy but problems of "fit" between traditional mental health services and minority families.

Adolescent↗
PubMed1988

Two-dimensional echocardiographic features of echinococcosis of the heart and great blood vessels. Clinical and surgical implications.

Echocardiographic findings in cardiac echinococcosis have been previously described in isolated cases, but no detailed account of the various echocardiographic aspects and their clinical and surgical implications have ever been reported. We present a retrospective analysis of the two-dimensional echocardiograms of 15 patients with hydatid cysts affecting the heart or great blood vessels. Two-dimensional echocardiogram features were compared with the main clinical syndromes. Surgical confirmation of the echocardiogram findings was available in 12 patients. The cyst sizes ranged from 0.5 to 12 cm in diameter. Eleven patients had single cysts, three patients had two cysts, and one patient had multiple cysts. Cysts were located in the intramyocardial region in nine patients, the pericardial in three, and the paracardial in another three. All intramyocardial cysts protruded into the adjacent cardiac chamber, but in only two patients was there significant tricuspid valvular dysfunction. Pericardial and mediastinal cysts showed compression of cardiac chambers or great blood vessels, and two cysts had ruptured into the descendent thoracic aorta or inferior vena cava. In most patients, two-dimensional echocardiographic images of hydatid cysts were those of a cystic mass having well-defined edges and internal trabeculations corresponding to daughter membranes. However, in four patients, two-dimensional echocardiographic images showed a "solid" mass instead of a cystic mass, and in one patient with the multivesicular variety of echinococcosis, the images showed a large mass with poorly defined edges having a honeycombed appearance causing lysis of the anterior arch of the second and third left ribs. The two-dimensional echocardiographic finding showed good correlation with main clinical syndromes, but anaphylactic reactions occurred in every cyst location. In one patient, postoperative two-dimensional echocardiography showed two small intramyocardial cysts that had not been noticed during preoperative two-dimensional echocardiography or during surgical examination. Pathological examination in the four patients with a solid mass showed replacement of the hydatid liquid by necrotic matter containing membrane residues with a foreign-body inflammatory reaction of a granulomatous type. In conclusion, two-dimensional echocardiography is a very useful tool for diagnosis and management of patients with cardiac echinococcosis, but the great diversity of findings regarding number, size, location, and appearance of cysts must be borne in mind to interpret correctly the two-dimensional echocardiograms.

Adult↗
PubMed1988

Mapping gold-labeled IgE receptors on mast cells by scanning electron microscopy: receptor distributions revealed by silver enhancement, backscattered electron imaging, and digital image analysis.

Immunogold labeling and silver enhancement techniques are widely used to determine density and distribution of cell membrane receptors by light and transmission electron microscopy. However, these techniques have not been widely used for receptor detection by scanning electron microscopy. We used antigen- or protein A-conjugated colloidal gold particles, together with silver enhancement, sequential secondary and back-scattered electron imaging (SEI and BEI), and digital image processing, to explore cell surface distribution of IgE-receptor complexes on RBL-2H3 cells, a rat leukemia line that provides a model for the study of mucosal mast cells. Cells were first incubated with a monoclonal antidinitrophenol IgE (anti-DNP-IgE) that binds with high affinity to cell surface IgE receptors. The resulting IgE-receptor complexes were cross-linked either with the multivalent antigen, DNP-BSA-gold, or with a polyclonal anti-IgE antibody. Antibody-treated cells were labeled after fixation with protein A-gold. Fixed, gold-labeled cell monolayers were silver enhanced (or not), dehydrated, critical point-dried, and coated with gold-palladium (for SEI analysis) or carbon (for combined SEI/BEI analysis). They were observed in an Hitachi S800 SEM equipped with a field emission tip and a Robinson backscattered electron detector. An image processor (MegaVision 1024XM) digitized images directly from the S800 microscope at 500-1000 line resolution. Silver enhancement significantly improves detection of gold particles in both SEI and BEI modes of SEM. On gold-palladium-coated samples, 20-nm particles are resolved by SEI after enhancement. BEI resolves 15-nm particles without enhancement and 5- or 10-nm particles are resolved by BEI on silver-enhanced, carbon-coated samples. Neither BEI nor SEI alone can yield high resolution topographical maps of receptor distribution (BEI forms images on the basis of atomic number contrast which reveals gold but not surface features). Image analysis techniques were therefore introduced to digitize, enhance, and process BEI and SEI images of the same field of view. The resulting high-contrast, high-resolution images were superimposed, yielding well-resolved maps of the distribution of antigen-IgE-receptor complexes on the surface of RBL-2H3 mast cells. The maps are stored in digital form, as required for computer-based quantitative morphometric analyses. These techniques of silver enhancement, combined BEI/SEI imaging, and digital image analysis can be applied to analyze density and distribution of any gold-labeled ligand on its target cell.

Cell Line↗
PubMed1988

An unusual presentation of acute monocytic leukemia: a case report.

We present a rare case of acute monocytic leukemia (AMoL) in which the initial finding consisted solely of cutaneous leukemic infiltrates without obvious bone marrow involvement. Eight months later a definitive bone marrow diagnosis of AMoL was made. Findings of histologic, immunohistochemical, cytochemical, and ultrastructural studies including postmortem examination are described. We believe that one should consider an extramedullary AMoL if the findings of a positive lysozyme stain and a mild to moderate monocytosis are present.

Aged↗
PubMed1987

The control of mediator release from RBL-2H3 cells: roles for Ca2+, Na+, and protein kinase C1.

Antigen-stimulated rat basophilic leukemia (RBL-2H3) cells release serotonin and other inflammatory mediators by a process that requires Ca2+ influx and increased cytoplasmic Ca2+ levels, and is mimicked by Ca2+ ionophores. We report here that the Ca2+ response to antigen and to ionomycin has two components, a Ca2+ spike and a Ca2+ plateau. In nominally Ca2+-free medium, both components of the Ca2+ response are inhibited and secretion does not occur. In Na+-free medium, the initial Ca2+ spike induced by antigen or ionomycin occurs, but the plateau is again absent and secretion is inhibited by 30 to 50%. Secretion is also reduced by 10(-4) M amiloride, an inhibitor of Na+ transport pathways, and by 10(-5) M concentrations of two amiloride analogs with greater activity than amiloride, respectively, against Na+ channels and Na+/Ca2+ exchange. Phorbol esters, which stimulate protein kinase C, enhance the Ca2+ plateau and secretion caused by suboptimal amounts of both antigen and ionomycin; this enhancement depends on extracellular Na+. The Na+ ionophore, monensin, mimics the Ca2+ plateau. From these data, we infer that the Ca2+ spike and plateau reflect separate responses of RBL-2H3 cells to antigen or ionomycin. We propose that the Ca2+ plateau results at least in part from the activation of a Na+-dependent Ca2+ influx pathway. One possible mechanism is that antigen binding stimulates a protein kinase C-regulated Na+ transport system. The resulting influx of Na+ may activate a Na+/Ca2+ antiporter that supports the Ca2+ plateau and mediator release.

Amiloride↗
PubMed1987

DNP-phycobiliproteins, fluorescent antigens to study dynamic properties of antigen-IgE-receptor complexes on RBL-2H3 rat mast cells.

In RBL-2H3 rat mucosal mast cells, the crosslinking of cell-surface IgE-receptor complexes by multivalent antigens initiates a sequence of responses leading to degranulation. We have developed a family of dinitrophenol (DNP)-conjugated fluorescent antigens to study dynamic membrane events associated with these responses. Lysyl groups on the phycobiliproteins, B-phycoerythrin and C-phycocyanin, were labelled with DNP, yielding fluorescent conjugates that cause the release of [3H]serotonin from anti-DNP-IgE-primed RBL-2H3 cells. The binding of these antigens to IgE-receptor complexes was observed by fluorescence microscopy and quantified by flow cytometry. Incubation with 1 microgram/ml DNP42-B-phycoerythrin stimulates maximum degranulation from IgE-saturated cells. Under these conditions, approximately 26 X 10(3) molecules of DNP42-B-phycoerythrin are bound per cell at equilibrium. The rate and extent of antigen binding and of antigen-stimulated mediator release decrease in parallel as the concentration and DNP:protein ratio of the fluorescent conjugates is reduced. Secretion stops immediately when the nonfluorescent monovalent antigen, DNP-lysine, is added to degranulating cell suspensions. DNP-lysine also displaces surface-bound antigen when added during the first minutes after multivalent antigen. However, the ability of DNP-lysine to displace surface-bound DNP42-B-phycoerythrin from IgE-receptor complexes decreases progressively with time. Treatment with dihydrocytochalasin B and several analogs that prevent antigen-stimulated F-actin assembly enhances secretion and delays the transition of antigen to its DNP-lysine-resistant form. Cytochalasin treatment also permits the long-range movement of antigen into surface caps.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

The blocked pinocytic activity of mitotic cells is restored in mitotic-interphase hybrids.

During mitosis there is an abrupt inhibition of a wide range of membrane functions, including fluid-phase and adsorptive pinocytosis. We have used cell hybrids formed between mitotic and interphase cells to approach the mechanism of this inhibition. We report that fluid pinocytosis is reactivated in the mitotic partner of hybrids formed between mitotic and interphase Chinese hamster ovary (CHO) cells. It thus appears that the interphase cell provides some necessary element(s) for membrane activity during mitosis. This dominance of interphase membrane properties stands in contrast with earlier evidence that mitotic nuclear properties dominate in similar mitotic-interphase hybrids.

Animals↗
PubMed1987

Heme-linked ionizations of myeloperoxidase detected by Raman difference spectroscopy. A comparison with plant and yeast peroxidases.

The pH-dependence of the oxidation state marker line v4 of human leucocyte myeloperoxidase is determined in the absence of chloride using Raman difference spectroscopy (RDS). A transition in the frequency of v4 with pK of 4.2 +/- 0.3 is found. The pK compares favorably with that previously determined by spectrophotometric titration and kinetic studies. The shift in v4 across the transition is -1.3 cm-1. The shift in v4 and other Raman marker lines indicates enhanced pi charge in the chlorin ring below the transition. The low frequencies of the oxidation state marker lines indicate that a structural change occurs near the chromophore, which results in the formation of a more pi-charge donating protein environment for the chlorin ring at low pH. The Raman results are discussed in terms of a proposed catalytic control mechanism based on charge stabilization of the energy of ring charge-depleted ferryl intermediates of the reaction with peroxide. The myeloperoxidase findings are compared with similar RDS results for ferrous horseradish peroxidase and ferric cytochrome c peroxidase.

Animals↗
PubMed1986

The community competence scale in the placement of the deinstitutionalized mentally ill.

Little systematic research has been directed towards the determination of appropriate residential placements for deinstitutionalized psychiatric patients. A previous study suggested that the Community Competence Scale (CCS), a 124-item multiscale instrument, had potential utility for community placement decisions. In the present study, the CCS was administered to 52 deinstitutionalized patients placed in an urban boarding home, a rural boarding home, and urban apartments. No significant differences on the CCS occurred attributable to urban vs. rural setting; accordingly, the urban and rural boarding home groups were combined. The CCS discriminated between patients placed in boarding home and apartment settings after variability between the groups associated with age and diagnosis had been removed. The CCS discriminated more effectively between the groups than did prior hospitalization, subsequent rehospitalization, or the Social Competence Scale (SCS). The CCS was significantly positively correlated with the SCS and significantly negatively correlated with previous hospitalization and age.

Adult↗
PubMed1986

A comparison of life events scoring methods as predictors of psychological symptomatology.

Seven scoring methods for the Life Events Survey (LES) were compared to determine which, if any, is superior for prediction of psychological symptomatology as measured by the Brief Symptom Inventory (BSI). Every scoring method tested, except one utilizing an individual's positive ratings of events, was significantly correlated with symptomatology. The method using an individual's negative ratings of events was a significantly better predictor than any other. These findings suggest several conclusions. First, nomothetic methods for weighting life events do not increase a scale's predictive ability beyond that achieved by a frequency count of events. Second, frequency of life events predicts psychological symptomatology only insofar as life events are perceived as negative. That is, positively perceived events do not predict symptomatology. Finally, a life events scale's predictive ability is increased by utilizing the individual's negative perceptions of events.

Adult↗
PubMed1986

A novel mitotic spindle pole component that originates from the cytoplasm during prophase.

Several unique aspects of mitotic spindle formation have been revealed by investigation of an autoantibody present in the serum of a patient with the CREST (calcinosis, Raynaud's phenomenon, esophageal dysmotility, schlerodacytyly, and telangiectasias) syndrome. This antibody was previously shown to label at the spindle poles of metaphase and anaphase cells and to be absent from interphase cells. We show here that the serum stained discrete cytoplasmic foci in early prophase cells and only later localized to the spindle poles. The cytoplasmic distribution of the antigen was also seen in nocodazole-arrested cells and prophase cells in populations treated with taxol. In normal and taxol-treated cells, the microtubules appeared to emanate from the cytoplasmic foci and polar stain, and in cells released from nocodazole block, microtubules regrew from antigen-containing centers. This characteristic distribution suggests that the antigen is part of a microtubule organizing center. Thus, we propose that a prophase originating polar antigen functions in spindle pole organization as a coalescing microtubule organizing center that is present only during mitosis. Characterization of the serum showed reactions with multiple proteins at 115, 110, 50, 36, 30, and 28 kD. However, affinity-eluted antibody from the 115/110-kD bands was shown to specifically label the spindle pole and cytosolic foci in prophase cells.

Autoantibodies↗
PubMed1985

Affective disorders and depression as measured by the Diagnostic Interview Schedule and the Beck Depression Inventory in an unselected adult population.

Rates, demographic correlates, and differential symptomatic expression as a function of gender of affective disorders and depression as measured by the Diagnostic Interview Schedule (DIS) and the Beck Depression Inventory (BDI) were examined in 298 paid adult volunteers selected by the random digit dialing method. According to the DIS, 7.7% were diagnosed as current affective disorder, 6% as current primary unipolar depression, 23.5% as lifetime affective disorder, and 19.5% as lifetime primary unipolar depression. According to the BDI, 19.8% scored depressed: 10.7% as mildly, 5.0% moderately, and 4.0% severely depressed, respectively. Of 11 demographic variables whose relation to DIS diagnoses were examined in a multivariate context, only occupation was correlated significantly with current primary unipolar depression. Of the same variables whose relation to BDI score was examined, education and race were correlated significantly with BDI score. There was no evidence of differential symptomatic expression as a function of gender as measured by lifetime diagnosis of primary unipolar depression on the DIS.

Adolescent↗
PubMed1985

Anticytoskeletal autoantibodies in the connective tissue diseases.

The sera of 103 patients with connective tissue diseases were studied for the presence of anticytoskeletal antibodies by using an indirect immunofluorescence method. PTK2 cells fixed with paraformaldehyde and digitonin were used as substrate. Antibodies to intermediate filaments were detected in sera of 85.7% of polymyositis/dermatomyositis (PM/DM), 62.8% of systemic sclerosis, 54.5% of rheumatoid arthritis, and 37.5% of systemic lupus erythematosus patients, and in 42.5% of normal sera. High titers of these antibodies, which were IgM, were present in 30% of patients' and 5% of normal sera. Antibodies to microfilaments were present in 11.6% of patients' sera and absent in all control sera. These antibodies were IgM or IgG. The switch from an IgM to an IgG antibody was observed in 1 patient. An IgG antibody to the spindle poles and midbody of mitotic cells was present in the serum of 1 patient with the CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasias). Antibodies to intermediate filaments and to microfilaments occur commonly in the connective tissue diseases, particularly in PM/DM, and are not detected with substrates or fixation methods used in routine antinuclear antibody testing.

Antibodies↗
PubMed1985

Membrane and cytoskeletal changes associated with IgE-mediated serotonin release from rat basophilic leukemia cells.

Binding of antigen to IgE-receptor complexes on the surface of RBL-2H3 rat basophilic leukemia cells is the first event leading to the release of cellular serotonin, histamine, and other mediators of allergic, asthmatic, and inflammatory responses. We have used dinitrophenol-conjugated bovine serum albumin (DNP-BSA) as well as the fluorescent antigen, DNP-B-phycoerythrin, and the electron-dense antigen, DNP-BSA-gold, to investigate dynamic membrane and cytoskeletal events associated with the release of [3H]serotonin from anti-DNP-IgE-primed RBL-2H3 cells. These multivalent antigens bind rapidly to cell surface IgE-receptor complexes. Their distribution is initially uniform, but within 2 min DNP-BSA-gold is found in coated pits and is subsequently internalized. Antigen internalization occurs in the presence and absence of extracellular Ca2+. The F-actin content of the detergent-extracted cell matrices analyzed by SDS PAGE decreases during the first 10-30 s of antigen binding and then increases by 1 min to almost double the control levels. A rapid and sustained increase is also observed when total F-actin is quantified by flow cytometry after binding of rhodamine-phalloidin. The antigen-stimulated increase in F-actin coincides with (and may cause) the transformation of the cell surface from a finely microvillous to a highly folded or plicated topography. Other early membrane responses include increased cell spreading and a 2-3-fold increase in the uptake of fluorescein-dextran by fluid pinocytosis. The surface and F-actin changes show the same dependence on DNP-protein concentration as stimulated [3H]serotonin release; and both the membrane responses and the release of mediators are terminated by the addition of the non-cross-linking monovalent ligand, DNP-lysine. These data indicate that the same antigen-stimulated transduction pathway controls both the membrane/cytoskeletal and secretory events. However, the membrane and actin responses to IgE-receptor cross-linking are independent of extracellular Ca2+ and are mimicked by phorbol myristate acetate, whereas ligand-dependent mediator release depends on extracellular Ca2+ and is mimicked by the Ca2+ ionophore A23187.

Actin Cytoskeleton↗