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Biomedical subjects

A Richardson

Publications and source records attributed to A Richardson.

At least 217 records · Page 12Linked to original sources
PubMed1992

A prospective, randomized, blind comparison of three biopsy techniques in the management of patients after renal transplantation.

Although conventional histology (CH) of needle core biopsies has been accepted as the gold standard for diagnosis of renal allograft rejection, this assumption has never been tested. Fine-needle aspiration cytology (FNAC) and monoclonal antibody (panleukocyte) staining of needle core biopsies (MABS) have been suggested to be superior to CH. A total of 50 patients received a cadaveric renal transplant followed by immunosuppression with triple therapy. Biopsies were taken routinely at days 7,14,21,28, and 90, with additional biopsies taken between these times if rejection was suspected (total biopsy sessions = 219). Specimens were taken for CH, FNAC, and MABS at each biopsy session, but only the result of one technique (previously randomly allocated) was communicated back to the clinical team, using a standardized grading system. Subsequently the presence or absence of rejection was determined by retrospective analysis of the clinical and biochemical course by 4 clinicians, without reference to the biopsy result. Graft survival was not significantly different in the three groups. The sensitivities for CH, FNAC, and MABS were 75%, 59%, and 77%, respectively, while the specificities were 87%, 96%, and 80%, respectively. Inadequate samples for analysis occurred frequently with the MABS technique--and, to a lesser extent, with CH--and both techniques tended to overdiagnose rejection. FNAC most often gave an answer but did miss clinically important rejection episodes. Needle-core biopsy processed for CH remains the most reliable biopsy technique for the diagnosis of rejection of renal allografts. FNAC is a useful technique for monitoring grafts with stable function or nonfunction. MABS does provide information equivalent to CH, but, in this study, had a high incidence of inadequate samples.

Antibodies, Monoclonal↗
PubMed1992

Hepatic focal nodular hyperplasia: a benign incidentaloma or a marker of serious hepatic disease?

Amongst 17 patients with hepatic focal nodular hyperplasia (FNH) encountered at Westmead Hospital between 1981 and 1990, FNH was found in association with hepatocellular carcinoma (HCC) in three (3/17), one male and two females, one of whom also had peliosis and an hepatic adenoma. FNH was also found in association with other conditions which may affect hepatic function, structure or circulation, including chronic obstructive airways disease (2), congestive cardiomyopathy (1), chronic active hepatitis (1), granulomatous hepatitis (1), coeliac artery stenosis (1) and metastatic malignant melanoma (1). This report, derived from our experience with FNH over 10 years draws attention to a possible link between FNH, hepatic malignancy and conditions which may disturb the hepatic circulation. We suggest that patients with FNH should be investigated thoroughly and an aggressive management policy should be adopted.

Adult↗
PubMed1992

Serum IgG and IgM levels in new and regular long-term plasmapheresis donors.

This Australian study monitored the effects of monthly plasmapheresis on donor serum IgG and IgM levels in 127 new and 124 established plasma donors who donated 1014 units over a five-month period. Of the 251 donors, 3% had reduced total serum protein (TSP) levels, 7% had low IgG levels and 12% had low IgM levels prior to donation on at least one occasion over the study period. Statistical analysis showed that the TSP, IgG and IgM levels of new donors who had donated plasma on less than 10 occasions were no more likely to fall below normal than those of old donors. However, new and old donors whose IgG or IgM levels fell below normal at any time during the study had significantly lower levels of the relevant parameter on entry to the study. Followed longitudinally, IgG and IgM levels in old and new donors tended to fall, although levels fluctuated throughout the study. Statistical analysis failed to show any correlation between TSP levels and IgG or IgM levels. These parameters did not correlate significantly with the number of previous plasmaphereses, donor weight, volume collected or history of infection. This study highlighted the need for regular, specific quantitation of IgG and IgM levels as well as TSP in regular plasmapheresis donors. The frequency of testing is yet to be determined, in view of the high materials and labour costs of such a programme.

Adolescent↗
PubMed1992

Prevalence of heart failure in three general practices in north west London.

There is little recent information on the prevalence of heart failure in the United Kingdom. Assuming that patients with heart failure would be taking diuretic drugs all such patients were identified in three general practices in north west London. The practice records of these patients were examined to determine which patients had heart failure. Of the 30,204 patients served by the practices, 117 had heart failure, a prevalence of 3.9 per 1000 patients. The mean age of these patients was 74 years. The prevalence of heart failure among patients under 65 years of age was 0.6 per 1000 patients rising to 27.7 per 1000 among those aged 65 years and over. The aetiology of heart failure was considered to be coronary heart disease for 32% of patients, valve disease for 19%, hypertension for 6%, cor pulmonale for 4% and congenital heart disease for 2%. The aetiology for the remaining 37% of patients was unknown. Most patients were referred to hospital and only 20% had been treated solely by the general practitioner. An electrocardiogram and chest radiograph had been obtained for over 80% of patients but only 28% had an echocardiogram. Heart failure occurs primarily in elderly patients, and coronary heart disease is the dominant aetiological factor.

Aged↗
PubMed1992

A ten-point plan for meeting carers' needs.

The needs of people requiring extra care--people who are elderly, chronically ill or disabled--are now gaining long overdue recognition. Yet the somewhat different needs of those who look after them at home--known as "carers"--remain largely ignored. Two years ago, representatives of a group of organizations in Britain joined together to commission a project to redress this balance. They were concerned both to set out the range of carers' needs and to issue guidance on the kinds of services necessary to meet them. These documents, prepared following extensive consultation with people working in the field, have now been published (Richardson et al, 1989). This short article provides a brief overview of the issues.

Caregivers↗
PubMed1991

Yellow spectacles to improve vision in children with binocular amblyopia.

Yellow spectacles were given to 20 children who had binocular amblyopia. Immediately, their vision improved. Furthermore, in the younger children, after they had worn the yellow lenses for up to nine months, this improvement persisted even when they were not wearing the spectacles. Yellow filters may help these children with binocular amblyopia because they remove the blue fringes that are due to chromatic aberration of the eye.

Adolescent↗
PubMed1991

Expression of superoxide dismutase and catalase in rat brain as a function of age.

Active oxygen species have been proposed to be involved in the aging process of the brain, therefore alterations of the levels of enzymes involved in the defence system against free radicals and other active species could substantially influence the aging process. In this study the enzyme activities of superoxide dismutase (Cu/Zn) and catalase as well as the relative levels of their mRNA were measured in the brain of Fischer F344 rats of various ages (5-37 months old). A gradual decrease in the activity of these enzymes (21-27%) was observed with increasing age. The alterations were paralleled by a decrease (39-40%) in the relative levels of these mRNA species. Thus the decrease in the activity of superoxide dismutase and catalase appears to be due to an age-dependent change in the expression of these genes.

Aging↗
PubMed1991

Structure and function of inositol trisphosphate receptors.

Inositol 1,4,5-trisphosphate (Ins(1,4,5)P3) is a soluble intracellular messenger formed rapidly after activation of a variety of cell-surface receptors that stimulate phosphoinositidase C activity. The initial response to Ins(1,4,5)P3 is a rapid Ca2+ efflux from nonmitochondrial intracellular stores which are probably specialized subcompartments of the endoplasmic reticulum, although their exact identities remain unknown. This initial response is followed by more complex Ca2+ signals: regenerative Ca2+ waves propagate across the cell, repetitive Ca2+ spikes occur, and stimulated Ca2+ entry across the plasma membrane contributes to the sustained Ca2+ signal. The mechanisms underlying these complex Ca2+ signals are unknown, although Ins(1,4,5)P3 is clearly involved. The intracellular receptor that mediates Ins(1,4,5)P3-stimulated Ca2+ mobilization has been purified and functionally reconstituted, and its amino acid sequence deduced from its cDNA sequence. These studies demonstrate that the Ins(1,4,5)P3 receptor has an integral Ca2+ channel separated from the Ins(1,4,5)P3 binding site by a long stretch of residues some of which form binding sites for allosteric regulators, and some of which are substrates for phosphorylation. In this review, we discuss the ligand recognition characteristics of Ins(1,4,5)P3 receptors, and their functional properties in their native environment and after purification, and we relate these properties to what is known of the structure of the receptor. In addition to regulation by Ins(1,4,5)P3, the Ins(1,4,5)P3 receptor is subject to many additional regulatory influences which include Ca2+, adenine nucleotides, pH and phosphorylation by protein kinases. Many of the functional and structural characteristics of the Ins(1,4,5)P3 receptor show striking similarities to another intracellular Ca2+ channel, the ryanodine receptor. These properties of the Ins(1,4,5)P3 are discussed, and their possible roles in contributing to the complex Ca2+ signals evoked by extracellular stimuli are considered.

Animals↗
PubMed1991

Induction of heat shock proteins in lymphocytes increases with mitogen stimulation.

The effect of the growth state of a cell on the ability of hyperthermia to induce the synthesis of heat shock proteins (HSPs) was studied in resting and concanavalin A (ConA)-stimulated lymphocytes. Hyperthermia induced the synthesis of hsp 110, hsp 90, hsc 70, and hsp 70 in both resting and ConA-stimulated lymphocytes, and ConA-treatment induced the synthesis of the hsp 90 and hsc 70 at normal temperature. The induction of the synthesis of hsp 110 and hsp 70 by hyperthermia was 3- to 6-fold higher for lymphocytes cultured with ConA for 12 and 24 h than in non-stimulated lymphocytes. Thus, lymphocytes induced to undergo proliferation showed a greater response to hyperthermia than resting lymphocytes.

Animals↗