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Biomedical subjects

S Cartwright

Publications and source records attributed to S Cartwright.

At least 19 recordsLinked to original sources
PubMed2001

Atopic asthma: differential activation phenotypes among memory T helper cells.

BACKGROUND: T cells have been implicated in the pathogenesis of atopic asthma. We have previously shown that memory T helper cells (CD4+CD45RO+) are preferentially activated relative to naïve T helper cells (CD4+CD45RA+) after bronchial allergen challenge. However, specific T helper subpopulations that are activated in atopy and/or asthma remain undefined. OBJECTIVE: To determine the T helper subpopulations and activation phenotypes relevant to acute and stable asthma that may be common with or distinct from atopy. METHODS: Two groups of atopic asthmatics (ten acute and nine stable asthmatics) and two non-asthmatic groups (14 non-asthmatic atopics and eight normal non-atopic controls) were analysed. Ten acute asthmatics were assessed in the emergency room during an acute episode (FEV1 43.6% +/- 18.4). Nine stable asthmatics were assessed during a symptom-free period (FEV1 85% +/- 6). Using multiple colour flow cytometry we analysed T cell subpopulations and the expression of IL-2-receptor (IL-2R) and MHC-class II antigens (MHC II) on naïve and memory T helper cells in the peripheral blood of asthmatic and non-asthmatic groups. RESULTS: Atopic asthmatics (acute and stable) had an increased percentage of memory T helper cells expressing IL-2R compared with normal non-atopics (mean SD 16.1 +/- 6%, 12.4 +/- 2% and 7.7 +/- 1.8%, P < 0.05) but not compared with non-asthmatic atopics (10 +/- 3.5%). Naïve T helper cells had low expression of IL-2R and MHC II in all four groups. MHC II antigen expression was increased in memory T helper cells of asthmatics (acute and stable) compared with normal non-atopics (13.9 +/- 7.5, 10.6 +/- 5 and 4.9 +/- 2.5, P < 0.05) but not compared with non-asthmatic atopics (7.92 4). A novel finding was that IL-2R and the MHC II molecules were mainly expressed in non-overlapping populations and coexpression was found predominantly on memory T helper cells. Asthmatics (acute and stable) had higher proportion of double positive memory T helper cells (IL-2R+MHC II+) compared with both non-asthmatic groups (P < 0.05). CONCLUSIONS: We demonstrate a differential expression of IL-2R+ and MCH II+ on CD45RO+ T helper cells that would suggest that there are three subsets of activated memory T helper cells in asthmatics. Two non-overlapping IL-2R+ or MHC II+ CD45RO+ T helper cells and a third subpopulation of activated cells that coexpress IL-2R and MHC II (double positives). This latter subpopulation is significantly higher in asthmatics (acute or stable) compared with both non-asthmatic groups, suggesting a specific T helper activation phenotype distinct to atopic asthmatics as compared with atopic non-asthmatics.

Acute Disease↗
PubMed2000

Effectiveness of a battery-powered toothbrush on plaque removal: comparison with four manual toothbrushes.

The objective of these four clinical studies was to evaluate the efficacy of the Colgate Actibrush battery-powered toothbrush in comparison with four top-selling manual European toothbrushes (Dr. Best Flex Toothbrush [Germany]; Reach Triple Action Ultra Clean Toothbrush [Germany]; Jordan Multi-Action Toothbrush [Norway]; and Sanogyl Systeme In'Side Double Action Toothbrush [France]) for plaque removal. Each clinical study used a single-use, examiner-blind design in which the Colgate Actibrush battery-powered toothbrush was compared with one of the 4 manual toothbrushes for removal of plaque in adult subjects after 24 hours of no oral hygiene. Supragingival plaque formation was assessed prebrushing and after a 1-minute supervised brushing with either the battery-powered toothbrush or 1 of the manual toothbrushes. After 24 hours of no oral hygiene, Colgate Actibrush removed statistically significantly more plaque than did all 4 of the manual toothbrushes. The results of these clinical studies support the conclusion that Colgate Actibrush is clinically superior for the control of supragingival plaque, compared with the leading selling European manual toothbrushes.

Adolescent↗
PubMed1997

An intervention strategy for workplace stress.

This article explores a range of sources of workplace stress and a three-prong intervention strategy for managing pressures at work. The three approaches highlighted are primary, secondary, and tertiary prevention interventions. Primary is concerned with stressor reduction, secondary with stress management and tertiary with remedial support. In addition, a number of wider policy issues are suggested, such as risk assessment, economic incentives, and specific measures to help small- and medium-sized workplaces in managing workplace stress.

Humans↗
PubMed1995

A critical pathway to evaluate suspected deep vein thrombosis.

Uncertainty regarding the optimal evaluation of suspected deep vein thrombosis (DVT) results in wide variations in practice, even within the same institution. To address variation in practice while maximizing the efficiency and quality of care, our institution developed a critical pathway guideline for the emergency department evaluation of patients suspected of having DVT. We present the critical pathway and the clinical rationale underlying its recommendations. The critical pathway was developed by a multidisciplinary team using chart review of practice at our institution, benchmarking at other institutions, and review and discussion of the medical literature. Consensus was achieved for the selection of ultrasound as the primary imaging test for all patients and for recommending initial doses of heparin sodium that are higher than the current norm at our institution to reduce the length of time required to achieve therapeutic anticoagulation. A total time for patient evaluation of 5 hours or less was established as the target. Controversy arose in two key areas: (1) the treatment of patients with normal ultrasound scans when high clinical suspicion for DVT exists and (2) the evaluation and treatment of suspected isolated calf-vein DVT. In its final form, the critical pathway recommendations seek to balance the benefits of standardization with the prerogatives of physicians to make decisions tailored to individual patients.

Decision Making↗
PubMed1991

Selective involvement of the spinal trigeminal nucleus in the conditioned nictitating membrane reflex of the rabbit.

These experiments were performed to test the hypothesis that a region associated with the trigeminal nuclear complex is selectively involved in mediating the classically conditioned nictitating membrane reflex in the rabbit. Microinjections of Lidocaine were used to produce a temporary, localized block of neural activity following the conditioning of the reflex using a standard tone/air puff-paired stimulus paradigm. Data indicate that the injection of Lidocaine at the medial pars oralis/reticular formation junction results in a selective suppression of the conditioned reflex.

Animals↗
PubMed1986

A new clinical-anatomic staging system for evaluating prognosis and treatment of prostatic cancer.

Because the existing systems of staging for prostatic cancer depend exclusively on the extent of anatomic spread, the stages do not demarcate distinctive patterns of survival, particularly in patients with extremely good or poor prognoses. In this research, we demonstrate that the evaluation of prognosis and therapy can be improved if anatomic staging is augmented by various features of the patients' clinical severity. In 280 patients with prostatic cancer, we first created rating scales for severity of three distinct clinical variables: symptoms referable to cancer; host factors unrelated to cancer; and overall level of function. In univariate analysis each of these clinical variables substantially affected 5-year survival for patients with similar anatomic stages, but in multivariate analysis, only the first two (symptoms and host factors) remained impressive. Retaining the anatomic stages and adding the two most important clinical variables, we then created a composite new staging system, containing four clinical-anatomic (C-A) categories. The new C-A categories were statistically more distinctive than conventional anatomic stages, and demarcated patients with more extreme high (91%) and low (8%) 5-year survival rates. In addition to the increased prognostic precision, the new C-A staging system demonstrated an important distinction in treatment. Although radical radiotherapy seemed superior to palliative therapy within conventional anatomic stages, the survival differences disappeared within the C-A stages.

Adult↗
PubMed1983

Comparison and evaluation of four serological tests for detection of antibodies to Aujeszky's disease virus.

Four methods used for the detection of antibodies to Aujeszky's disease virus in porcine sera were compared. The serum neutralisation test, countercurrent immunoelectrophoresis test, micro-immunodiffusion test and the enzyme-linked immunosorbent assay (Elisa) were assessed with particular regard to their use in large scale screening of porcine serum samples. The Elisa test was found to be the most suitable on the grounds of sensitivity, speed and cost.

Animals↗
PubMed1979

The [14C]-aminopyrine breath test. A comparison of different forms of analysis.

1 Following ingestion of [14C]-aminopyrine, breath 14CO2 data were analysed from normal individuals, patients with hepatic disease, epileptics receiving anticonvulsant therapy and volunteers before and after treatment with glutethimide. 2 The 'standard' 2 h [14C]-aminopyrine breath test discriminated successfully between the main groups but failed to detect the change in microsomal enzyme function produced by glutethimide. 3 A 'modified' form of the 2 h breath test calculated from the area under the breath specific activity curve detected the increase in demethylation following glutethimide. 4 The breath elimination constant (Kb) derived from the breath 14CO2 disappearance curve was as sensitive as the 'modified' 2 h breath test and was simpler to compute. 5 Glutethimide 500 mg/day for 14 days resulted in a 42% increase in the metabolic clearance of antipyrine and a 26% increase in demethylation of [14C]-aminopyrine.

Aminopyrine↗
PubMedDate not supplied

Maturation antigens present in epididymis of cynomolgus monkeys (Macaca fascicularis).

PROBLEM: The present study was carried out to evaluate the changes in morphology and motility of spermatozoa retrieved from different regions of the epididymis of the cynomolgus monkey. The role of the epididymis in sperm maturation is assessed by assaying protein synthesis within different regions of the epididymis and by correlating these with changes in spermatozoal membrane surface components. METHOD: Spermatozoa retrieved from proximal caput (CP), midcorpus (CO), and distal cauda (CD) were assessed by morphological evaluation and computerized motion analysis. Membrane surface proteins of spermatozoa of different epididymal regions were extracted and separated on SDS-PAGE. Protein synthesis of different regions of the epididymis were assayed in vitro by [35S]-methionine incorporation. RESULTS: Spermatozoa obtained from different regions of the epididymis differed morphologically only in the location of the cytoplasmic droplet. Specifically, from caput to corpus to cauda, sperm steadily exhibited a more distal cytoplasmic droplet. When the motion parameters of velocity and amplitude of the lateral head were examined, CP spermatozoa were not progressively motile, and poor duration of movement was most noticeable for CO spermatozoa compared with CD spermatozoa. Membrane extracts from CP, CO, and CD epididymal monkey spermatozoa differed in only several protein bands. Three major polypeptide bands (19, 30, and 60 kD) that were absent from CP sperm were present in CO and CD sperm, with the latter showing increased intensity. Several polypeptides were lost from the sperm during epididymal transit: a 25-kD band was lost in CD sperm; and bands at 27 kD, 50-52 kD, and 90 kD were only present for CP sperm. Additionally, regional differences exist for proteins secreted by the cynomolgus monkey epididymis. Proteins (15, 25 kD) were only secreted in the CP region; a 38-kD protein increased in intensity from the CP to CD regions, whereas a 21-kD protein was absent from CD-secreted medium. CONCLUSION: These preliminary findings permitted the identification of several "maturational antigens" for cynomolgus monkey spermatozoa. Further characterization of these antigens that are modified during epididymal transit is warranted to determine their significance in the acquisition of progressive motility and fertilizing ability by epididymal spermatozoa.

Animals↗