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Biomedical subjects

A Ellis

Publications and source records attributed to A Ellis.

At least 73 records · Page 4Linked to original sources
PubMed1994

Learning to read: the role of short-term memory and phonological skills.

This study investigates the relationships between reading, short-term memory and phonological skills, and the mechanisms responsible for the short-term memory differences found between groups of children differing in reading ability. Differences were found between groups of good, average, and poor readers in verbal, but not visual, short-term memory and these differences were well explained in terms of differences in speech rate (an index of rehearsal rate) between the groups. Measures of phonological ability, rhyme awareness and phoneme deletion, also showed strong differences between the different reading ability groups. Regression analyses showed that rhyme awareness, phoneme deletion, and speech rate (but not verbal short-term memory) had independent predictive relationships to reading skill. These findings show that phonological skills do not represent a unitary trait, and that different facets of phonological ability are important in predicting the development of reading skills.

Child↗
PubMed1993

Preparation and characterization of basolateral membrane vesicles from pig and human colonocytes: the mechanism of glucose transport.

Membrane vesicles were isolated from the basolateral domains of pig and normal human colonocytes. The activity of the ouabain-sensitive K(+)-activated phosphatase, the basolateral membrane marker, was enriched 13-fold in these membrane vesicles over the original homogenate. The membranes displayed cross-reactions with antibodies to the (Na+/K+)ATPase and the RLA class I major histocompatibility antigen, both known indicators of the basolateral membrane. There was negligible contamination by other organelles and the luminal membrane, as revealed by marker-enzyme analysis and Western blotting, using an antibody to villin. The vesicles transported D-glucose in a cytochalasin B-inhibitable Na(+)-independent manner, with a Km of 28.1 +/- 0.8 mM and Vmax. of 3.1 +/- 0.4 nmol/s per mg of protein. The transport was inhibited by 2-deoxy-D-glucose and 3-O-methyl-D-glucose, but not by L-glucose or methyl-alpha-D-glucose. Probing the colonocyte basolateral membranes with an antibody against the C-terminus of the human liver GLUT 2 produced a cross-reaction at 52 kDa. These properties indicate the presence of a GLUT 2 isoform on the basolateral membranes of human and pig colonocytes.

3-O-Methylglucose↗
PubMed1993

Phase I study of Topotecan, a new topoisomerase I inhibitor, in patients with refractory or relapsed acute leukemia.

The purpose of this study was to define, in a phase I study in leukemia, the maximally tolerated dose (MTD), major toxicities, and possible antitumor activity of Topotecan, a new topoisomerase I (topo I) inhibitor. Topotecan was delivered by a 5-day continuous infusion every 3 to 4 weeks to patients with refractory or relapsed acute leukemia, at doses ranging from 3.5 mg/m2 to 18 mg/m2 per course. Twenty-seven patients were treated, including 17 patients with acute myelogenous or undifferentiated leukemia, 7 with acute lymphocytic leukemia, and 3 with chronic myelogenous leukemia in blastic phase. Severe mucositis was the dose-limiting toxicity occurring in two of five patients treated with Topotecan 11.8 mg/m2 per course; a third patient had prolonged myelosuppression. At the MTD of 10 mg/m2 per course, 1 of 12 patients had severe mucositis and 5 had mild-to-moderate mucositis. Nausea, vomiting, diarrhea, and prolonged myelosuppression were uncommon. Three patients (11%) achieved a complete response, two (7%) had a partial response, and one (4%) had a hematologic improvement. The overall complete plus partial response rate was 19%, and 24% in acute myelogenous or undifferentiated leukemia. A novel in vitro assay that quantifies Topotecan-stabilized topo I-DNA complexes in patient samples was used, which demonstrated heterogeneity in the ability of Topotecan to interact with topo I, the intracellular target of Topotecan. This phase I study defined the MTD of Topotecan to be 10 mg/m2 by continuous infusion over 5 days every 3 to 4 weeks in patients with refractory or relapsed acute leukemia. Severe mucositis was the dose-limiting toxicity. Future studies will define the precise activity of Topotecan in different leukemia subsets, its efficacy in combination with other antileukemic drugs, and correlations between Topotecan-induced topo I-DNA complex formation and individual patient response to Topotecan.

Acute Disease↗
PubMed1993

The effect of liquid fibre on gastric emptying in the rat and humans and the distribution of small intestinal contents in the rat.

A combination of the polysaccharide ethyl-hydroxyethyl-cellulose (EHEC) and the surfactant sodium-dodecylsulphate (SDS) has the extraordinary physical property of being liquid at room temperature but gelling firmly at 37 degrees C. It has been named 'liquid fibre' and its effect on gastric emptying has been tested in rats and humans, as well as its effect on intestinal distribution in rats. Rats were gavaged with 5 ml of radiolabelled liquid fibre, SDS in water, or water control. Subgroups were killed after 25, 50, 100, 200, and 300 minutes, the gut removed, and the distribution of radioactivity measured scintigraphically. Liquid fibre gelled in the stomach and spread exponentially down the small intestine before 25 minutes. This distribution was maintained for 200 minutes after which the stomach began to empty again. In the human study, 10 healthy men drank 250 ml liquid fibre and placebo labelled with 1.85 MBq technetium tin colloid on separate occasions. Gastric emptying was measured by gamma-camera. Half emptying time significantly increased from 17.7 to 55.8 minutes (means, p < 0.05). The time for 10% to empty (which includes any lag time) increased from 7.0 to 19.4 minutes (p < 0.05). Average emptying rate decreased from 4.49%/min for placebo to 1.60%/min for liquid fibre (p < 0.01). The dramatic delay in gastric emptying suggests liquid fibre may have clinical applications while its liquid formulation should improve acceptability.

Adult↗
PubMed1992

Aspects of neurosurgical assessment using the Glasgow Coma Scale.

The Glasgow Coma Scale (GCS) has become a cornerstone of the neurological/surgical assessment of patients used by both nursing and medical staff. Since its development in the 1970s it has been used in a variety of clinical situations to monitor changes in a number of key neurological functions, including level of consciousness, pupil reaction and limb movement. During this time, however, there have been suggestions that there are problems with some of the measurement principles underlying its use, which in part has stimulated the development of other neuro-assessment tools. Irrespective of measurement device, there is always the possibility of error or incorrect assessment. In the field of neurosurgery, as with other high dependency environments, a patient's condition can change rapidly. Additionally, there is the association of certain assessment responses with nursing and medical interventions. Thus, accuracy in all aspects of assessment and recording is paramount. Despite the growing body of literature surrounding the GCS, little is known about the pattern of errors made by nursing staff using the GCS to assess neurosurgical patients. This study compared the assessment findings of Registered General Nurses (RGNs), Enrolled Nurses and Student Nurses after viewing videotaped neuro-assessments of patients in a high dependency unit. The criterion for judging the accuracy of subject's assessments was established by a panel of experts. As expected, RGNs had the highest proportion of correct assessments and students the least. Subjects were identified as having difficulty in determining the relative amounts of weakness that a patient exhibited, and in correctly distinguishing between flexion and extension.

Glasgow Coma Scale↗
PubMed1992

Group rational-emotive and cognitive-behavioral therapy.

The theory of rational-emotive therapy (RET) and of cognitive-behavioral therapy (CBT) is briefly explained and is applied to group therapy. It is shown how RET and CBT therapy groups deal with transference, countertransference, levels of group intervention, process versus content orientation, identifying underlying group process themes, here-and-now activation, working with difficult group members, activity levels of therapist and group members, and other group problems. Although they particularly concentrate on people's tendencies to construct and create their own "emotional" difficulties, RET and CBT group procedures fully acknowledge the interactions of human thoughts, feelings, and actions and active-directively employ a variety of cognitive, emotive, and behavioral group therapy techniques.

Cognitive Behavioral Therapy↗
PubMed1992

Occupational stress in neurosurgery: an exploratory study.

Occupational stress in nursing has been a popular topic for investigation. In particular, comparisons between practice areas such as the intensive care unit (ICU) and medical-surgical unit have attempted to identify what factors are stressful, and whether some nursing environments are more stressful than others. Such studies have led to inconclusive findings. While many practice areas have been studied, the neurosurgical ICU and neuromedical/neurosurgical units have largely been overlooked. Using interviews, this exploratory study examined aspects of nursing perceived as stressful by staff members working in ICU and medical-surgical units in a neuroscience center. Findings suggested that patient care, communication, workload, management and supervision, organizational and personal circumstances are major sources of stress. These findings are in keeping with studies of stress conducted in national and international non-neurosurgical nursing practice areas.

Burnout, Professional↗
PubMed1992

The in-vitro mucosal conjugation of ethinyloestradiol and the bioavailability of oral contraceptive steroids in patients with treated and untreated coeliac disease.

The ethinyloestradiol (EO2) component of oral contraceptive steroids is extensively conjugated with sulphate by the gut wall. The ability of gastrointestinal mucosa to conjugate EO2 has been examined in vitro in samples of mucosa taken from normal women as well as from women with coeliac disease. The percentage conjugation per mg dry weight for normal tissue (n = 11) was 17.1 +/- 6.4 (mean +/- s.d.) while in untreated coeliac tissue (n = 6) the figure was 6.3 +/- 3.6% (P less than 0.01). In tissue from patients with treated coeliac disease (n = 5) the figure was 12.1 +/- 3.2%. Thus the ability of intestinal mucosa to conjugate ethinyloestradiol was significantly reduced in patients with coeliac disease, and restored towards normal following treatment. However, in patients with coeliac disease the pharmacokinetics of ethinyloestradiol were not significantly different from normal controls.

Administration, Oral↗
PubMed1992

Use of serum from patients with polycythaemia or haemochromatosis for laboratory external quality assurance exercises.

Some External Quality Assessment Schemes (EQAS) require large volumes of human serum. During a one year period, 595 units of blood were obtained from 87 patients with haemochromatosis and polycythaemia, who underwent therapeutic venesection at the Edinburgh and South East Scotland Blood Transfusion Service. Serum from 59% of these donations was used in the EQAS for peptide hormones and related substances. The cost of the serum collection was 109 pounds/litre, but was only 33 pounds/litre of serum if the cost of the actual venesection was excluded. Results from tests on the sera were satisfactory in a variety of immunoassays for several different hormones. EQA schemes with requirements for large volumes of serum should consider therapeutic venesection as a cost effective means of obtaining serum.

Adult↗
PubMed1991

Abnormalities of differentiation and maturation in the oesophageal squamous epithelium of patients with tylosis: morphological features.

Tylosis is an autosomal dominant inherited defect of keratinization, associated in two Liverpool families with a high risk of developing oesophageal squamous carcinoma. In 29 individuals, followed by regular endoscopy and biopsy, we have noted several morphological abnormalities of the epithelium in this pre-cancerous condition. A control group of 43 non-tylotic patients with normal oesophageal histology and a further 26 patients with acute oesophagitis was used for comparison. Recognizable dysplasia was confined to the older age range in the tylotic group and was present in four patients. Almost half of the patients showed acute inflammation. Abnormalities of maturation were common, the most frequent being the presence of prominent basophilic inclusions and clear cell acanthosis, with parakeratosis and frank surface keratinization present in smaller numbers. There was, however, no statistically significant difference between the tylotic and inflamed control groups for any of these features. The only feature to show a significant difference between these groups was the presence of individual cell keratinization. The results suggest that in the oesophageal epithelium of the patients with tylosis, inflammation is the predominant abnormality, together with individual cell keratinization, and that these lesions appear in a much younger age group than dysplasia.

Adolescent↗
PubMed1990

Preparation and properties of brush-border membrane vesicles from human small intestine.

This study describes a simple and rapid method for the preparation of brush-border membrane vesicles from intestinal biopsies. The specific activities of sucrase, amino peptidase N, and alkaline phosphatase in these vesicles were the same as those in vesicles prepared from intestinal segments. The vesicles from all the regions of the small intestine can transport D-glucose in an Na+-dependent manner. The rates of transport of D-glucose presented here are far higher than previously reported. The method should have a wide applicability to studies of transport mechanisms and the distribution of transport processes within the intestine.

Adult↗
PubMed1990

Divine intervention and the treatment of chemical dependency.

Alcoholics Anonymous and related 12-step programs are the predominant influence on chemical dependency treatment programs in the United States today. 12-step programs have a strong religious orientation, despite rationalizations that Higher Power need not mean the traditional definition of God. The teaching of religious beliefs is not a proper function of therapists treating addictions in a general population. Moreover, teaching patients they can only recover through the intervention of a Higher Power locks them into a pattern of dependence on something outside themselves in order to function. 12-step programs have helped millions of people. Even more could be helped were they to eliminate the concept of needing a Higher Power.

Alcoholics Anonymous↗
PubMed1990

Studies of intestinal lymphoid tissue. XIV--HLA status, mucosal morphology, permeability and epithelial lymphocyte populations in first degree relatives of patients with coeliac disease.

Fifty two first degree relatives of patients with coeliac disease were investigated for HLA status, small intestinal permeability, and mucosal morphology together with the size of the intraepithelial lymphocyte pool and indices of lymphocyte activation, in an attempt to identify genetically determined markers of the disease. Thirty eight per cent of these subjects had increased intraepithelial lymphocyte populations and a highly significant association with HLA-DR3 compared with controls. Their intestinal permeability to 51chromium-labelled ethylenediamine tetraacetate was invariably normal and there was no evidence of abnormal mucosal architecture, increased crypt cell mitotic activity or lymphocyte 'activation'. Although increased intraepithelial lymphocyte counts clearly do not cause alterations in intestinal structure or function, it is likely that this parameter together with the HLA-DR3 status identifies a genetically determined predisposition to the disease which may only become clinically evident with larger doses of ingested gluten.

Adolescent↗