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J Richardson

Publications and source records attributed to J Richardson.

At least 235 records · Page 13Linked to original sources
PubMed1993

Quality-adjusted life years: origins, measurements, applications, objections.

Quality-adjusted life years or QALYs are used to combine, in a single measure, information about the quantity and quality of life produced by a health intervention. They have been used as outcome measures in clinical trials and in cost-effectiveness analyses. This paper describes how QALYs are assessed and how they are used. Methodological and theoretical problems are discussed as are ethical objections to the utilitarian ethos underlying their use. It is concluded that QALYs are part of a technology that is still in development but, because of the lack of alternatives, they will certainly continue to be used. It is important to resolve the outstanding methodological issues and reach an ethical consensus to ensure that QALYs truly reflect community goals.

Australia↗
PubMed1993

Sequences responsible for the distinctive hemolytic potentials of Friend and Moloney murine leukemia viruses are dispersed but confined to the psi-gag-PR region.

Friend and Moloney murine leukemia viruses (F- and M-MuLV) induce distinct diseases in hematopoietic tissues following inoculation of newborn mice of susceptible strains. F-MuLV induces erythroleukemia preceded by severe early hemolytic anemia; M-MuLV induces thymomas and only very mild hemolysis. The major viral determinant of severe early hemolytic anemia residues in the env gene, but sequences located outside this gene can modulate this effect. By means of genetic chimeras of F- and M-MuLV, we have found that although they are confined to the 5' portion of the env gene intron, sequences that determine the distinctive hemolytic potentials of F- and M-MuLV are widely distributed over a region spanning the RNA encapsidation domain, the gag gene, and the portion of the pol gene encoding the viral protease. Within this large region, two fragments of M-MuLV, a 1.3-kb region encoding the matrix, pp12, and capsid proteins and a 0.8-kb region encoding the nucleocapsid and the viral protease, were capable, individually, of partially attenuating the capacity of F-MuLV for induction of severe early hemolytic anemia. In association, these two fragments conferred complete attenuation. Moreover, a second pair of adjacent fragments within this large region appeared to behave cooperatively to confer complete attenuation; a 0.36-kb region roughly corresponding to the encapsidation domain, although not detectably altering hemolytic potential on its own, deepened the attenuation conferred by the adjacent 1.3-kb region. Whether capable of inducing severe early hemolytic anemia or not and despite different efficiencies of induction of recombinant polytropic viruses, all chimeric viruses retained the erythroleukemogenicity of the F-MuLV parent.

3T3 Cells↗
PubMed1992

The antitumor activity of an anti-CD22 immunotoxin in SCID mice with disseminated Daudi lymphoma is enhanced by either an anti-CD19 antibody or an anti-CD19 immunotoxin.

The antitumor activities of immunotoxins (ITs) constructed with deglycosylated ricin A chain (dgA) and either anti-CD19 (HD37) or anti-CD22 (RFB4) monoclonal antibodies were compared in SCID mice with disseminated human Daudi lymphoma (SCID/Daudi). As reported previously, after intravenous injection with Daudi cells, SCID mice develop disseminated lymphoma, which infiltrates the vertebral column and causes paralysis of the hind legs before death. The mean paralysis time (MPT) has been taken as an end point in this tumor model. We have previously reported that early treatment of SCID/Daudi mice with RFB4 coupled to dgA prolongs the MPT in a manner consistent with the killing of 4 logs of tumor cells. In the present study, we show that HD37-dgA kills 2 logs of tumor cells. The lower potency of the HD37-dgA is consistent with its lower IC50 on Daudi cells in vitro. We further show that the antitumor activity of a mixture of HD37-dgA and RFB4-dgA is significantly enhanced in SCID/Daudi mice and is consistent with the killing in excess of 5 logs of tumor cells. However, identical enhancement was observed when a mixture of the RFB4-dgA and the HD37 antibody was administered. In contrast, enhancement was not observed when mice were injected with a mixture of the RFB4 antibody and the HD37-dgA. The results indicate that a "cocktail" of HD37 antibody and RFB4-dgA immunotoxin can have significant antitumor activity in this mouse model of lymphoma and suggest that combinations of particular antibodies and ITs may have cooperative antitumor activity.

Animals↗
PubMed1992

Os calcis fractures: a randomized trial comparing conservative treatment with impulse compression of the foot.

Published data suggest that soft tissue involvement plays a role in the aetiology of residual symptoms following fractures of the os calcis. This randomized study involved 23 patients with 24 intra-articular fractures of the calcaneum. It was designed to evaluate the efficacy of a pneumatic plantar impulse device in reducing pain, associated morbidity and convalescent time. The results show a significant improvement in subtalar range of movement in the pumped group at 3 months, with pain significantly reduced at 6 months and at 1 year. There was no difference in weight bearing or walking distance between the pumped and control groups. The time from date of injury to return to work was significantly reduced in the pumped group by an average of 3 months.

Adult↗
PubMed1992

Observation of overt pain behaviour by physicians during routine clinical examination of patients with low back pain.

Observation of overt pain behaviours was carried out by physicians during routine clinical examination of 120 patients with chronic low back pain. Reliable ratings were achieved but only after very careful standardization in an additional 60 pilot patients. Overt pain behaviour was found to be related to other clinical measures of illness behaviour--pain drawing, behavioural symptoms, behavioural signs, use of walking aides and downtime--but did tap an additional dimension. It is concluded that clinical observation of overt pain behaviour can provide useful additional information about illness behaviour in low back pain. Reliable observations can be achieved in a carefully standardized research situation but in routine clinical practice are vulnerable to considerable observer error and bias.

Adult↗
PubMed1992

The toxicity of chemically deglycosylated ricin A-chain in mice.

Tumor-reactive antibodies coupled to ricin or its A-chain (immunotoxins) have been used in rodents and humans to treat a variety of neoplastic diseases. Side-effects of such treatment include hepatotoxicity, vascular leak syndrome, myalgia and low grade fever. At high doses, severe toxicities include liver damage, pulmonary edema, aphasia, rhabdomyolysis and kidney failure. There have been a limited number of toxicologic studies on uncoupled ricin or its A-chain and none on deglycosylated A-chain. Since the latter has been utilized in "second generation" immunotoxins, the current studies were carried out to evaluate the toxicities induced by deglycosylated ricin A-chain (dgA) in mice. The administration of dgA to normal BALB/c mice causes early (24 h) weight loss and late (10 day) accumulation of ascites. These effects could be partially altered by changing the route of injection of dgA from i.v. to i.p. Thus, i.p. administration caused weight loss but not ascites, whereas i.v. administration caused both. Weight loss was associated with reduced fluid intake by the treated mice, and was not associated with increased levels of serum TNF-alpha. SCID mice injected with the same dose of dgA as normal BALB/c mice developed ascites, but it was of lesser severity, suggesting that a functional immune system, differences in microbial flora, or strain differences may be involved in the development of ascites.

Animals↗
PubMed1992

A cost utility analysis of mammography screening in Australia.

Cost utility analysis is the preferred method of analysis when quality of life instead is an important outcome of the project being appraised. However, there are several methodological issues to be resolved in implementing cost utility analysis, including whether to use generalised measures or direct disease specific outcome assessment, the choice of measurement technique, and the combination of different health states. Screening for breast cancer meets this criterion as mammographic screening has been shown to reduce mortality; and it is said that earlier treatment frequently results in less radical surgery so that women are offered the additional benefit of improved quality of life. Australia, like many other countries, has been debating whether to introduce a national mammographic screening programme. This paper presents the results of a cost utility analysis of breast cancer screening using an approach to measuring outcome, Healthy Year Equivalents, developed within this study to resolve these problems. Descriptions of breast cancer quality of life were developed from surveys of women with breast cancer, health professionals and the published literature. The time trade off technique was then used to derive values for breast cancer treatment outcomes in a survey of women in Sydney, Australia. Respondents included women with breast cancer and women who had not had breast cancer. Testing of (i) the effect of prognosis on the value attached to a health scenario; and (ii) whether the value attached to a health scenario remains constant over time has been reported. The estimate of the net costs of screening are reported. The costs of breast cancer screening include the screening programme itself, the further investigations and the subsequent treatment of breast cancer cases. Breast cancer is treated in the absence of screening, many commentators claim earlier treatment is costly but there is little evidence. Therefore we have investigated current patterns of breast cancer treatment, current use of investigations for women presenting with symptoms and current use of covert mammography screening. The results are extrapolated to obtain estimates of the costs and outcomes presented as cost per healthy year equivalent. This analysis produces important information for the Australian policy debate over mammography. It also contributes to the development of cost utility analysis and the approach developed here can be applied more generally.

Australia↗
PubMed1992

An epidemic methicillin-resistant strain of Staphylococcus aureus in Spain.

During 1990, a strain of methicillin-resistant Staphylococcus aureus became epidemic in Spain and spread in a manner analogous to that of EMRSA-1 in England. Isolates of this strain produced little protein A and were resistant to a number of antibiotics including ciprofloxacin. Beta-lactamase production was encoded by a c. 39 kb plasmid, which also conferred resistance to mercury, cadmium, ethidium bromide and propamidine isethionate. Investigation showed that two variants, separable by supplementary and Fisk phage typing, were circulating. The B variant appeared to spread more readily than the A variant. The opportunity was taken to compare the discriminatory power of traditional typing methods with molecular techniques. The discriminatory power of the molecular techniques used only reached the same level as the traditional methods when double enzyme digestion of total cellular DNA by EcoR I and Cla I was performed.

Bacterial Typing Techniques↗
PubMed1992

Anterior subcapsular plaque cataract in hyperornithinaemia gyrate atrophy--a case report.

Hyperornithinaemia gyrate atrophy (HOGA) is a rare autosomal recessive disorder in which chorioretinal degeneration occurs with cataracts, myopia, and hyperornithinaemia. We report the case of an 18-year-old female who presented with the typical features of HOGA, including posterior subcapsular cataracts and elevated plasma ornithine. She later developed distorted vision in both eyes owing to wrinkling of the anterior lens capsules. Histological examination following lens extraction showed the wrinkling was caused by focal distortion from capsular fibrosis (anterior subcapsular plaque cataract). This specific lens change has not been linked previously with HOGA.

Adolescent↗
PubMed1992

The value of health care: what can we learn from Oregon?

The scarcity of health care resources leads to rationing amongst potential users by one means or another. When the market is rejected, rationing should be conducted on the basis of systematic and informed priority setting. It has been widely suggested that these priorities should be based on health benefits measured by quality adjusted life years (QALYs) and recently the US State of Oregon has attempted to use QALYs for setting priorities on a large scale. Values not normally associated with QALY analysis were also incorporated in the process. Their unique experience is of interest in Australia, as no attempt has been made here to prioritize medical interventions on the scale that was undertaken in Oregon.

Australia↗
PubMed1992

Cost utility analysis: 'new directions' in setting health care priorities.

It is an inescapable fact of any health care system that consumers are not the agents who decide between technical alternatives. Consequently, the agents making choices need an acceptable framework for measuring and comparing costs and benefits of competing programs. Cost Utility Analysis (CUA) is proposed as the appropriate framework for health care decision making. It combines the significant aspects of health (quality and quantity of life) that are gained from an intervention. At present, there is no other methodology which does this in a way that permits decisions to be based on consumer preference.

Australia↗