Oestrogen receptor isoforms, their distribution and relation to progesterone receptor levels in breast cancer samples.

Oestrogen receptors (ER) in breast cancer tumours are highly heterogeneous. In this study, the variability in the profile of ER isoforms and its relation to progesterone receptor (PgR) levels in breast tumours has been studied. Using high resolution isoelectric focusing (IEF) 4 ER isoforms can be detected with pI values of 6.1 (corresponding to the 8S ER), and 6.3, 6.6 and 6.8 (all of which have a sedimentation pI values of 6.1 (corresponding to the 8S ER), and 6.3, 6.6 and 6.8 (all of which have a sedimentation coefficient of approximately 4S in sucrose density gradients). Data were obtained on the soluble receptors from supernatants of 66 ER-positive primary breast tumour homogenates using high resolution IEF. In 43 of these samples PgR levels were also measured. The isoform at pI 6.6 was present in 97.0% of tumours, the isoform at pI 6.1 in 83.3%, the pI 6.3 isoform 39.4% of tumours and the pI 6.8 isoform in only 33.3% of tumours. Only 12.1% of tumours studied contained the full complement of ER isoforms (pI 6.1, 6.3, 6.6 & 6.8). The ER isoforms at pI 6.1 & 6.8 were only found in PgR-positive (> 10 fmol PgR/mg protein) tumours. Some tumours contained only a single ER isoform at pI 6.6 or 6.1, but those at pI 6.3 and 6.8 were never found singly. Tumours containing 3 or 4 ER isoforms had significantly higher levels of PgR (> 90 fmol/mg protein) than those with only 1 or 2 (P < 0.001). The presence of ER isoforms at pI 6.3 and pI 6.8 also significantly correlated with high levels of PgR (P < 0.001). This variability in the ER isoform profile of breast tumours and their correlation with PgR levels may have a bearing on prognosis and tumour response to endocrine therapy.     

The effectiveness of computer screen filters

We have compared the performance of a variety of computer screen filters which are currently available in Australia. The filters tested included six neutral density filters and 10 mesh filters. The testing incorporated measurements of the filters' effectiveness in reducing the luminance of specular and diffuse reflections, along with an analysis of the effect of the filters on screen luminance/contrast at a variety of viewing angles (from 0^o to 50^o). As groups, the neutral density filters with antireflection coatings and mesh filters performed significantly better than neutral density filters without antireflection coatings in reducing die luminance of specular reflections. For diffuse reflections, die neutral density filters with antireflection coatings performed significantly better than mesh filters in reducing the luminance of die reflections. The performance of mesh filters in reducing specular reflections was significantly positively correlated widi die density of die mesh. All filter types caused reductions in screen luminance and contrast widi increase in off-axis viewing angles.     

Acknowledgement of referees

Interaction of tamoxifen, trioxifene and LY117018 with cytosol-estrogen receptors from immature rat uteri was compared. Determination of relative binding affinity (RBA) by competition with [³H] estradiol under various assay conditions revealed that the RBA of LY117018 increased with temperature while that of tamoxifen and trioxifene declined. Furthermore, the RBA values of tamoxifen and trioxifene observed after 24 h of incubation at 4°C were significantly lower than those obtained with 1-h incubations. However RBA values obtained with 1- or 24-h incubations of LY117018 at 4°C were similar. The complex formed by estradiol or LY117018 at 4°C was relatively stable for 24 h, while significant dissociation of tamoxifen and trioxifene was detected under these conditions. At 30°C estradiol displayed a biphasic pattern of dissociation, but tamoxifen and trioxifene dissociated rapidly and little evidence of a stable phase was apparent. By contrast, the complex formed by LY117018 exhibited greater stability than that of estradiol at 30°C. These results establish a relationship between shifts in competition curves (RBA) and rates of dissociation relative to estradiol; and clearly reveal that LY117018 has different binding characteristics than tamoxifen and trioxifene.     

Telephone triage, expert systems and clinical expertise

This paper reports on a qualitative study of the use of an expert system developed for the British telephone triage service NHS Direct. This system, known as CAS, is designed to standardise and control the interaction between NHS Direct nurses and callers. The paper shows, however, that in practice the nurses use CAS in a range of ways and, in so doing, privilege their own expertise and deliver an individualised service. The paper concludes by arguing that NHS Direct management's policy of using CAS as a means of standardising service delivery will achieve only limited success due not only to the professional ideology of nursing but also to the fact that rule-based expert systems capture only part of what 'experts' do.     

An electron microscopic study of rubrospinal projections to the lumbar spinal cord of the opossum

The rubrospinal system is a major suprasegmental input to the important interneuronal pool at the base of the lumbar dorsal horn in the North American opossum. After appropriate lesions, rubral axons and their synaptic terminals were found in electron micrographs of lamina IV, V and VI as well as within the dorsal extreme of lamina VII. Degenerating terminals contact small diameter dendrites in the lateral terminal zone and large dendritic profiles in the medial terminal zone. Correlating these data with the dendritic arborizations of interneurons in Golgi preparations and with existing physiologic studies, it appears that interneurons in the intermediate and medial aspects of lamina V, VI and VII receive rubral input on both their proximal and distal dendrites.     

Assessing competence in communication and interpersonal skills: the Kalamazoo II report.

Accreditation of residency programs and certification of physicians requires assessment of competence in communication and interpersonal skills. Residency and continuing medical education program directors seek ways to teach and evaluate these competencies. This report summarizes the methods and tools used by educators, evaluators, and researchers in the field of physician-patient communication as determined by the participants in the "Kalamazoo II" conference held in April 2002. Communication and interpersonal skills form an integrated competence with two distinct parts. Communication skills are the performance of specific tasks and behaviors such as obtaining a medical history, explaining a diagnosis and prognosis, giving therapeutic instructions, and counseling. Interpersonal skills are inherently relational and process oriented; they are the effect communication has on another person such as relieving anxiety or establishing a trusting relationship. This report reviews three methods for assessment of communication and interpersonal skills: (1) checklists of observed behaviors during interactions with real or simulated patients; (2) surveys of patients' experience in clinical interactions; and (3) examinations using oral, essay, or multiple-choice response questions. These methods are incorporated into educational programs to assess learning needs, create learning opportunities, or guide feedback for learning. The same assessment tools, when administered in a standardized way, rated by an evaluator other than the teacher, and using a predetermined passing score, become a summative evaluation. The report summarizes the experience of using these methods in a variety of educational and evaluation programs and presents an extensive bibliography of literature on the topic. Professional conversation between patients and doctors shapes diagnosis, initiates therapy, and establishes a caring relationship. The degree to which these activities are successful depends, in large part, on the communication and interpersonal skills of the physician. This report focuses on how the physician's competence in professional conversation with patients might be measured. Valid, reliable, and practical measures can guide professional formation, determine readiness for independent practice, and deepen understanding of the communication itself.