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Biomedical subjects

K Steele

Publications and source records attributed to K Steele.

84 records · Page 5Linked to original sources
PubMed1982

Self-instruction and learning disabilities: maintenance, generalization, and subject characteristics.

The present study assessed the effects of self-instructional training on learning-disabled children's perceptual deficits. Twenty-nine children (M age = 9.70 years) were assigned randomly to a control (n = 10), an attention-placebo control ( = 9), and self-instruction group (n = 10). Analyses of covariance (with the pretest score as the covariate) yielded significant treatment effects at post- and maintenance testing, although there was no evidence whatsoever of any generalization to academic performance of classroom behavior. Analysis of the frequency of overt self-verbalizations at post- and maintenance testing further suggested the efficacy of self-instructions for direct treatment effects. Finally, the importance of S characteristics in self-regulation programs was emphasized: Children with an internal locus of control orientation tended to use overt self-verbalizations most frequently.

Adolescent↗
PubMed1981

Increased detection of mammary carcinoma cells in marrow smears using antisera to epithelial membrane antigen.

We have developed a technique for the immunocytochemical staining of marrow smears using antiserum to epithelial membrane antigen (EMA). This membrane component is confined to, but widely distributed in, epithelial tissues and tumours derived from them, and is strongly expressed by infiltrating breast carcinoma cells. Marrow aspirates from patients with both early and metastatic breast cancer have been examined, and the results of immunocytochemical staining compared with conventional cytology and histology. Staining with antiserum to EMA enabled us to detect small numbers of carcinoma cells, and increased the yield of positive samples. Furthermore, using this technique, we found malignant cells in the marrow of patients with primary breast cancer with no other evidence of metastatic disease. Thus immunocytochemical staining for EMA may be of value in the detection of micrometastases in patients with primary breast carcinoma.

Antigens, Surface↗
PubMed1981

Use of antisera to epithelial membrane antigen for the cytodiagnosis of malignancy in serous effusions.

A new human antigen, designated epithelial membrane antigen (EMA), has recently been described on surface membranes of a wide variety of normal epithelium but not on connective tissue cells. The antigen is only weakly expressed on normal or reactive mesothelium. Increased expression of the antigen has been observed in most neoplasms of epithelial origin and in malignant mesothelioma. We have investigated the possibility of using this difference in the expression of the antigen to distinguish between mesothelial cells and malignant cells in cytological smears of serous effusions. This distinction cannot always be made on morphological grounds alone and problems of differential diagnosis are encountered in about 15% of all specimens of serous effusions sent for cytological examination. Using antisera to EMA we have applied an indirect immunoalkaline phosphatase technique to alcohol-fixed smears prepared from serous effusions and have found that intense staining of the antigen is confined to effusions from patients in whom there is either clinical or cytological evidence of malignancy. The technique proved to be especially useful in cytologically equivocal cases, where there were problems of differential diagnosis.

Antigens, Surface↗
PubMed1979

A new antigen on the epithelial membrane: its immunoperoxidase localisation in normal and neoplastic tissue.

Using antisera raised against defatted human cream we have demonstrated a new antigen on the epithelial membrane. An indirect immunoperoxidase technique on routinely processed histological sections was used, and we describe results which show that this antigen has a widespread but highly selective distribution, being apparently localised to membranes that have a secretory function. The antigen is carried by a variety of adenocarcinomas, suggesting that its localisation may have a role in the diagnosis and differential diagnosis of malignant disease.

Antigens↗
PubMed1973

The presence of tumour-specific membrane antigen in the serum of rats with chemically induced sarcomata.

Antibodies to the tumour-specific transplantation type antigen (TSTA) of a transplanted methylcholanthrene-induced sarcoma (MC-1) in syngeneic rats were studied using the techniques of indirect membrane immunofluorescence and mixed haemadsorption with a (51)Cr-labelled indicator cell. After tumour excision, anti-TSTA antibody was readily measurable in both serum and lymph. In contrast, the tumour-bearing animal had no measurable anti-TSTA antibody in the serum but low titres in the lymph. Consequently, we formed the hypothesis that in the presence of a growing tumour the serum contained antigen-antibody complexes with antigen in excess.To test this hypothesis, tumour-bearing serum was examined for the presence of free antigen and antigen-antibody complexes by 2 different methods. In the first method, tumour-bearing serum was cross-linked with glutaraldehyde and was found to absorb specifically the anti-TSTA antibody, indicating free circulating TSTA. Next, antigen-antibody complexes were split with salt or acid and separated into a low molecular weight (or "antigen") fraction (<100,000) and a high molecular weight (or "antibody") fraction (>100,000). The low M.W. fraction specifically inhibited the anti-TSTA antibody when tested by either membrane immunofluorescence or mixed haemadsorption, indicating the presence of antigen from antigen-antibody complexes in the tumour-bearing circulation. The possible effect on the host's immune response of circulating free tumour antigen and antigen-antibody complexes are discussed.

Animals↗
PubMed1972

Thymus-derived lymphocytes produce an immunologically specific macrophage-arming factor.

Spleen cells from mice immunized with an allogeneic tumor when cultured with the specific tumor cells release into the supernatant a specific macrophage-arming factor(s) (SMAF) which binds nonspecifically to macrophages from both mice and rats and renders these cytotoxic to the specific tumor cells. SMAF also binds in an immunologically specific way to the target cells. SMAF-treated target cells grow normally in the absence of macrophages but are killed in the presence of normal macrophages. Thymus-derived cells are necessary for the production of SMAF since (a) after treatment with anti-theta serum immune spleen cells fail to release SMAF; (b) spleen cells from immunized T cell-deprived mice (thymectomized as adults followed by whole body irradiation and restored with bone marrow) fail to produce SMAF on stimulation with the specific target cells. While SMAF has the properties of a cytophilic antibody, it does not belong to one of the established classes of immunoglobulin since high activity is found after column separation in a fraction having a molecular weight between 50,000-60,000 daltons.

Animals↗
PubMedDate not supplied

Socio-economic gradients in self-reported health in Ireland and Northern Ireland.

BACKGROUND: Research and policy related to reducing health inequalities has progressed separately within Ireland and Northern Ireland. This paper describes the first exploration of the socio-economic influences on health on the island of Ireland since 1922. METHODS: Postal survey. RESULTS: The response rate was 52%; 11,870 respondents. Men reported more long-standing illness (LLTI) or poor general health (PGH); depression was more common amongst women. Socio-economic gradients in health were evident in both jurisdictions, with the effects of household income being particularly marked. Overall, morbidity levels were significantly better in Ireland than in Northern Ireland: adjusted odds ratio of 0.79 (95% CI 0.71 - 0.88) for LLTI; 0.64 (0.57 - 0.72) for PGH; 0.90 (0.82 - 0.99) for depression. CONCLUSIONS: There is evidence of strong and similar socio-economic gradients in health throughout the island of Ireland. This would suggest joint policy approaches or at least further comparative evaluation of the initiatives in each jurisdiction.

Adolescent↗
PubMedDate not supplied

Transmission of Ebola virus (Zaire strain) to uninfected control monkeys in a biocontainment laboratory.

Secondary transmission of Ebola virus infection in humans is known to be caused by direct contact with infected patients or body fluids. We report transmission of Ebola virus (Zaire strain) to two of three control rhesus monkeys (Macaca mulatta) that did not have direct contact with experimentally inoculated monkeys held in the same room. The two control monkeys died from Ebola virus infections at 10 and 11 days after the last experimentally inoculated monkey had died. The most likely route of infection of the control monkeys was aerosol, oral or conjunctival exposure to virus-laden droplets secreted or excreted from the experimentally inoculated monkeys. These observations suggest approaches to the study of routes of transmission to and among humans.

Aerosols↗