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D S Cox

Publications and source records attributed to D S Cox.

29 records · Page 2Linked to original sources
PubMed1984

Oral induction of the secretory antibody response by soluble and particulate antigens.

The ability of gastric intubation of a soluble or a particulate form of dinitrophenylated bovine gamma-globulin (DNP-BGG) to induce salivary IgA antibody was examined. Gastric intubation of the particulate form of the antigen tended to induce a greater response than did equivalent doses of the soluble form. However, systemic immunization with the soluble form of the antigen prior to gastric intubation of antigen increased the salivary IgA response. Prior systemic injection of the particulate form did not increase the salivary IgA response. Immunoreactivity of the particulate moiety of the particulate antigen did not seem to be a factor in the observed differences, since three different synthetic particulate antigens with identical hapten-protein moieties produced the same results (i.e. prior injection with the synthetic particulate antigens did not increase the salivary IgA response).

Administration, Oral↗
PubMed1984

Symptoms of emotional distress in a family planning service: stability over a four-week period.

The 25-item Hopkins Symptom Checklist ( HSCL -25) was used on two occasions four weeks apart to identify self-reported symptoms of anxiety and depression in patients attending a family planning service. Only 28 per cent of patients classified as anxious to start with remained so four weeks later, but 62 per cent of those with high depression scores and 74 per cent of those with high depression and high anxiety scores maintained significant levels of depression. The implications of these findings for routine screening are discussed.

Adult↗
PubMed1983

A sensitive double isotope modification of the Farr assay using beta-particle emitters.

A sensitive modification of the ammonium sulfate precipitation assay for antibody affinity is described. The assay combines small reaction volumes and a 32P volume marker to determine the average relative affinity of small amounts of antibody to DNP hapten. The assay is relatively safe since two beta-particle emitters are utilized instead of two gamma-ray emitters. The assay has proven useful for the determination of small amounts of antibody such as might be found in secretions and column fractions.

Ammonium Sulfate↗
PubMed1982

Salivary antibody response and priming stimulated by soluble or particulate antigens injected at a remote secretory site.

The salivary antibody response produced after remote secretory site (mammary gland) injection of soluble or particulate DNP antigens was examined in the rat. IgA and IgG salivary antibody and IgG serum antibody concentrations were determined by an ELISA technique. Two experiments were performed using DNP-BGG as the soluble antigen and either DNP-S. mutans or DNP-BGG-S. mutans as particulate antigens. Approximately equivalent IgA antibody responses were produced when soluble or particulate antigens were injected locally at a secretory site. However, a greater salivary IgA response was observed with the soluble antigen when the antigens were injected in the vicinity of a secretory site (mammary glands) remote from the salivary glands (experiment 1: 123 +/- 46 vs 2 +/- 1 ng IgA per millilitre of saliva, and experiment 2: 212 +/- 59 vs 45 +/- 21 ng IgA per millilitre of saliva). In both experiments, prior remote secretory site injection of the soluble antigen was able to prime for a significantly increased salivary IgA response (more than three-fold) after a local injection in the vicinity of the salivary gland. The particulate antigens did not lead to priming of the salivary antibody response. Prior remote secretory site injection of soluble antigen, but not of the particulate antigens, also increased salivary and serum IgG antibody levels above the levels observed with an injection at either site alone.

Animals↗
PubMed1979

Co-operativity of lectin binding to fibroblasts and its relation to cellular actomyosin.

We have investigated the binding of 125I-concanavalin A (125I-Con A) and 125I-succinyl concanavalin A (125I-s-Con A) to rat fibroblasts (16C line) as a function of the concentration of added lectin, and the alterations to this binding behaviour caused by drugs which modify the cytoskeleton. The changes in cell behaviour which occur at different levels of binding have also been studied. As shown previously for some other systems, the binding of Con A is complex and partly co-operative. Three phases can be distinguished in our system: (i) pre-nucleation binding, (ii) binding which shows a small positive slope in a Scatchard plot and a Hill coefficient greater than unity, and which therefore is incipiently co-operative, and (iii) post-co-operative binding. The co-operative phase of binding is paralleled by progressive inhibition of EGTA-mediated cell detachment from substrata, with inhibition being complete when this phase of binding is complete. Likewise, the phagocytosis of latex spheres is progressively inhibited up to a threshold which coincides with the completion of co-operative binding. Thirdly, cells pretreated with Con A round up with colchicine (10(-5) M) if co-operative finding is complete, but adopt broad epithelial shapes if it is not. s-Con A does not show cooperative binding, and correspondingly does not inhibit EGTA-mediated cell detachment, or show a distinct threshold in the inhibition of phagocytosis, or promote the 2 types of shape change with colchicine. The pattern of Con A binding is drastically altered by pretreatment of cells with cytochalasin B or azide. The Scatchard and Hill plots show that the co-operative phase remains and is complete at about the same level of binding, but that it is more readily nucleated and takes place against a changed number and/or distribution of receptors. Pretreatment of cells with colchicine causes changes in the pattern of binding which are different from those observed with cytochalasin B or azide and are more difficult to interpret. We conclude that a reciprocal relationship exists between the cellular actomyosin and the state of cell surface receptors. Perturbation of actomyosin by cytochalasin B or azide can enhance the freedom of some receptors to participate in a co-operative rearrangement which facilitates the binding of further molecules of lectin. Vice versa, the co-operative event has a feedback influence on the cellular actomyosin to cause alterations of cellular response.

Actomyosin↗
PubMedDate not supplied

A feasibility test of a brief educational intervention to increase fruit and vegetable consumption among callers to the Cancer Information Service.

BACKGROUND: In this paper, results are reported from a pilot study designed to test the feasibility of a proactive educational intervention delivered to callers of the Cancer Information Service (CIS). METHODS: The study used a randomized two-group design (intervention vs control). Callers assigned to the intervention condition received a brief educational intervention at the end of usual service to increase fruit and vegetable consumption. As part of the intervention, key education messages and materials drawn from the 5 A Day for Better Health program of the National Cancer Institute were provided to CIS callers over the telephone and then reinforced with two follow-up mailings. RESULTS: Results from this pilot study indicated high levels of adherence to protocol by CIS Information Specialists who delivered the intervention to eligible CIS callers. Results obtained from the 4-week telephone follow-up interviews indicated that intervention subjects (n = 142) reported higher consumption of fruits and vegetables, averaging approximately 0.75 servings more per day (P < 0.01) than control subjects (n = 134). CONCLUSION: Nearly 80% of CIS callers endorsed the strategy of providing 5 A Day information at the end of usual service, even if such information was not specifically requested by the caller (i.e., the information was provided to CIS callers proactively.

Adult↗