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Biomedical subjects

M Dobson

Publications and source records attributed to M Dobson.

At least 55 records · Page 3Linked to original sources
PubMed1993

Framing and labelling effects in health descriptions: quality adjusted life years for treatment of breast cancer.

At present there is a growing interest in the use of cost-utility analysis (CUA) to a point where it merits serious consideration by health care decision makers. However, there remain a number of theoretical and practical issues to be resolved including the way in which quality of life information is presented and described to subjects. Two potential sources of influence in the construction of the quality adjusted life year (QALY) values elicited for a recent Australian CUA of mammography screening have been investigated. 180 subjects were randomly allocated to nine different presentations of two breast cancer health descriptions to investigate the impact of some framing and labelling effects. No statistically significant differences were found in the valuations placed on these descriptions when framing and labelling effects were taken into account, either as separate framing and labelling factors or as interactions with one another. A significant difference was found in the particular values of descriptions that were written in the third person that differed in terms of whether the word "cancer" was used. The main contribution of these data is to the robustness of the health descriptions used in the cost-utility analysis of mammography screening.

Aged↗
PubMed1993

Imagery ability and source monitoring: implications for eyewitness memory.

The present study investigated the effect of self-reported vividness of visual imagery on the ability to discriminate between memories derived from two external sources of information. Subjects were shown a film of a crime and were then given a written description of the event which included information not seen in the film. In a source monitoring task, high and low imagers were found to be equally proficient in recognizing items as previously presented, but high imagers were poorer at discriminating the source of items based on the written description. This finding is considered in terms of possible encoding and retrieval differences resulting from imagery vividness. The role of vivid visual imagery as a variable underpinning confusions in eyewitness testimony is discussed.

Cues↗
PubMed1992

Searching for synaptonemal complex proteins and their genes.

As an alternative to the production and use of monoclonal antisynaptonemal complex (SC) antibodies to isolate SC genes, we have explored the use of polyclonal anti-SC antibodies to identify SC genes from a cDNA expression library. The method proved relatively simple, reliable, and fast and has yielded two SC genes. A homologue of one of these genes from a different species has previously been isolated in another laboratory.

Animals↗
PubMed1992

Individual differences in anxiety level and eyewitness memory.

The present study investigated the relationship between individual differences in anxiety and eyewitness performance. Instructions designed to produce evaluative threat were given to anxious and nonanxious subjects at encoding and/or at retrieval. The performance of those subjects who were given anxiety-arousing instructions at encoding and retrieval and who scored high on the Test Anxiety Scale (TAS; Sarason, 1972) was less accurate on an eyewitness task than was that of the subjects who scored low on the scale. This difference in performance was attributable to improvement in the performance of nonanxious subjects, rather than debilitation in the performance of anxious subjects. Faced with the threat of failure, low-anxious subjects appeared to have the potential for increased effort. High-anxious subjects seemed to perform at or near capacity under all the experimental conditions because of their predisposition for task-irrelevant worry, which limited the possibility of an increase in working memory capacity.

Adult↗
PubMed1990

Expression of the Aspergillus niger glucose oxidase gene in A. niger, A. nidulans and Saccharomyces cerevisiae.

We report the cloning of the Aspergillus niger glucose oxidase gene and its use to elevate glucose oxidase productivity in A. niger by increasing the gene dosage. In addition, the gene has been introduced into A. nidulans where it provides the novel capacity to produce glucose oxidase. A plasmid, in which DNA encoding the mature form of glucose oxidase was preceded by a Saccharomyces cerevisiae secretion signal, effected high-level production of extracellular glucose oxidase in this yeast.

Amino Acid Sequence↗
PubMed1988

Purification and partial characterization of a plasminogen activator inhibitor from the human glioblastoma, U138.

A plasminogen activator inhibitor was purified to apparent homogeneity from conditioned media of U138 cells. The inhibitor is a glycoprotein with a pI of 5.4 and an apparent molecular weight of 45,000. The inhibitor forms sodium dodecyl sulfate-stable complexes with plasminogen activators and trypsin but not with plasmin, thrombin, or pancreatic kallikrein. Some biochemical and immunochemical characteristics of the U138 inhibitor distinguish it from other known plasminogen activator inhibitors. The expression of this inhibitor by U138 cells could be modulated by incubation in phorbol myristate acetate, interleukin-1, tumor necrosis factor, and gamma interferon, but not in beta interferon. Thus, the expression of the plasminogen activator inhibitor can be influenced by biological response modifiers known to be active in the brain and in the neural response to inflammatory stimuli. Therefore, this inhibitor, along with protease nexin, may be involved in brain development and regulation.

Autoradiography↗
PubMed1988

Endothelial cell heterogeneity: antioxidant profiles determine vulnerability to oxidant injury.

Human umbilical vein endothelial cells were more sensitive to hydrogen peroxide lysis than cow pulmonary artery endothelial cells. Conversely, activated neutrophils which utilize hydrogen peroxide-mediated cell cytotoxicity cell mechanisms were more toxic to the cow pulmonary artery cells. This discordance was not related to neutrophil adhesion to either cell type or cell passage number. The antioxidant profiles of the endothelial cells revealed that cow pulmonary artery cells were rich in catalase to consume bolus hydrogen peroxide presented to them, while human umbilical vein endothelial cells utilize glutathione peroxidase-linked mechanisms to detoxify a slower more sustained release of hydrogen peroxide generated by neutrophils. Endothelial cells from different species and sites may utilize diversified antioxidant protective mechanisms.

Animals↗
PubMed1971

Attitudes and long-term adjustment of patients surviving cardiac arrest.

Twenty patients surviving cardiac resuscitation following myocardial infarction were seen at least six months after the cardiac arrest. The patient and spouse were interviewed separately. Though they had not usually been informed by the medical staff, 16 of the 20 patients were aware that a cardiac arrest had occurred and had a good understanding of what this meant. Six patients remembered the start or end of the cardiac arrest and five specifically remembered external cardiac massage. Their feelings and their attitudes to the cardiac arrest are described.Initial anxiety was experienced by all the patients and their spouses, particularly after hospital discharge, but in the long term only five patients failed to make a reasonably satisfactory adjustment. Poor rehabilitation seemed to be mainly associated with persisting physical disability and personality factors and not with features associated with the cardiac arrest, such as the duration of external cardiac massage. The spouses often found it difficult to know exactly how to treat the patients after hospital discharge and most patients and spouses felt that more explanation and discussion with the medical staff would have helped to alleviate anxiety.

Adult↗
PubMed1969

Study of patients' psychological attitudes to a coronary care unit.

Seventy-four consecutive male patients aged 38 to 63 years were admitted to a coronary care unit with their first myocardial infarction. Their attitude to the unit was studied by interview and personality tests. Only six patients found the unit anxiety-provoking. Dependency feelings were found to occur frequently, both after transfer from the unit to the general wards and after discharge from hospital. It is suggested that the weaning process from the unit should be gradual and that at least one follow-up outpatient appointment should be arranged, as well as good liaison between the family doctor and the hospital.

Adult↗
PubMed1966

A clinical trial of four hypnotic drugs.

A CLINICAL TRIAL OF FOUR HYPNOTIC DRUGS WAS CARRIED OUT: Ro 4-5360, 10 mg. (Mogadon), methyprylon, 200 mg. (Noludar), Ro 4-5360, 5 mg. (Mogadon), secobarbital sodium, 100 mg. (Seconal), and a placebo. The study was on the usual double-blind basis, and all observations were made by a full-time nurse. Capsules were given at 10 p.m. for five successive nights, with two nights free from medication or observation. There were five such periods. The nurse carried out her observations right through the night, determining whether the patients were awake or asleep. Each of these drugs was statistically significantly different from the placebo, in terms of length of sleep. Differences between the individual drugs were not significant. The length of action of the various drugs appeared to be similar, with a somewhat longer period of activity for the Mogadon in both dosages. The major side effect was some drowsiness: this was more marked with Mogadon 10 mg. With the hypnotics, the patients had, on the average, about one hour more sleep than on the placebo.

Adult↗
PubMedDate not supplied

Misdiagnosis of appendicitis in nonpregnant women of childbearing age.

A retrospective case series was conducted at a teaching hospital with an emergency department (ED) census of 100,000 patients per year to identify the incidence of, and factors associated with, the misdiagnosis of appendicitis in nonpregnant women aged 15 to 45 years. There were 174 nonpregnant women identified with a pathologic diagnosis of appendicitis. Clinical features were then compared between patients misdiagnosed (seen in prior 10 days and given an incorrect diagnosis) and those who were initially diagnosed correctly. The results showed that 33% of the women with appendicitis were initially misdiagnosed. The most common misdiagnoses included pelvic inflammatory disease, gastroenteritis, and urinary infections. Misdiagnosed women more frequently exhibited diffuse and bilateral lower abdominal pain and tenderness, cervical motion, and right adnexal tenderness. Misdiagnosed women also had a lower incidence of right lower quadrant pain and tenderness, and peritoneal signs. In addition, misdiagnosis was associated with an increased incidence of perforation, abscess formation, and an increase in the total length of hospitalization. In conclusion, the incidence of misdiagnosis of appendicitis in women of childbearing age is high. Women who are misdiagnosed have less typical symptoms and physical findings and more frequent abnormal pelvic findings than those who are diagnosed correctly. Emergency physicians should be aware that atypical signs and symptoms are associated with misdiagnosed appendicitis in nonpregnant women of childbearing age.

Adolescent↗
PubMedDate not supplied

Purification and characterization of the plasminogen activator inhibitors PAI-1, PAI-2, and PN-1 from the human glioblastoma U138.

This investigation presents data which indicate that the plasminogen activator inhibitor (PAI) activity secreted from U138 cells is composed of three separate PAIs: PAI-1, PAI-2, and PN-1. It was demonstrated that the U138 PAI-1-like protein had an apparent molecular mass of 50 kilodaltons (kDa) and was purified to apparent homogeneity by elution from an anti-PAI-1 immunoaffinity column. These fractions were also reactive with a second anti-PAI-1 monoclonal antibody using immunoblotting techniques. Northern blot analysis of RNA isolated from unstimulated U138 cells demonstrated positive hybridization with the cDNA specific for human PAI-1. The U138 PAI-2-like protein was adherent to an anti-PAI-2 immunoaffinity column and was demonstrated to be nonadherent to concanavalin A-agarose, heparin-Sepharose, and the anti-PAI-1 immunoaffinity column. The eluted U138 PAI-2-like protein was demonstrated to have an apparent molecular mass of 60 kDa and was also reactive with a second anti-PAI-2 monoclonal antibody using immunoblotting techniques. Further, the cDNA specific for PAI-2 was demonstrated to hybridize to a 2.5-kilobase message from RNA isolated from U138 cells. A third PAI was detected that was nonadherent to concanavalin A-agarose and both of the anti-PAI columns. This 50-kDa PAI was adherent to heparin-Sepharose and thrombin-agarose columns, and was not reactive with any antibodies for either PAI-1 or PAI-2. Northern blot analysis of U138 RNA demonstrated positive hybridization with an oligodeoxynucleotide specific for PN-1. This investigation demonstrates with biochemical, immunological, and molecular data that the U138 glioblastoma constitutively produces three PAIs.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗