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D Robinson

Publications and source records attributed to D Robinson.

At least 289 records · Page 16Linked to original sources
PubMed1993

Comparison of patient-controlled analgesia with and without a background infusion after lower abdominal surgery in children.

Forty children aged 6-12 yr undergoing appendicectomy were allocated randomly to receive postoperative i.v. morphine by a patient-controlled analgesia (PCA) system (bolus dose 20 micrograms kg-1 with a lockout interval of 5 min) or the same PCA with a background infusion of morphine 20 micrograms kg-1 h-1. Patients breathed air and oxygen saturation was monitored by continuous pulse oximetry. Scores for pain, sedation and nausea were recorded hourly. Patients with PCA + background infusion received significantly more morphine than those with PCA only. Both groups self-administered similar amounts of morphine using the PCA machine. There were no significant differences in the pain scores of the two groups. Patients with PCA+background infusion suffered more nausea (P < 0.01), more sedation (P < 0.05) and hypoxaemia (P < 0.001) than those with PCA only. They also had a better sleep pattern than those with PCA only.

Analgesia, Patient-Controlled↗
PubMed1993

Lymphocyte subset responses to trauma and sepsis.

One hundred five trauma patients admitted to three trauma centers with injury Severity Scores of 20 or greater had lymphocyte phenotypic subsets characterized throughout their hospital course. Total lymphocytes, pan-T (CD2), helper T (CD4), suppressor T (CD8), pan B (CD20), and DR expressing lymphocytes were quantitated by monoclonal antibodies and flow cytometric analysis. Results were analyzed between three patient groups: uninfected, uneventful recovery (n = 64); major infection (n = 26); and dead (n = 15; 7 with sepsis). A significant lymphopenia, maximal at 3 days, occurred in the first postinjury week compared with controls (p < 0.05), which recovered over the study period. A hierarchical distribution was found between the three outcome groups with the lowest numbers of several lymphocyte phenotypes in those who died. T helper and suppressor cells were similarly affected, but lowest in patients destined to develop infection or die. The helper-suppressor ratio, however, was similar in all three outcome groups. Therefore, modulation early after injury aimed at restoring these subsets may reduce the risk of subsequent infection.

Adolescent↗
PubMed1993

Prednisolone treatment in asthma is associated with modulation of bronchoalveolar lavage cell interleukin-4, interleukin-5, and interferon-gamma cytokine gene expression.

Although corticosteroids are effective in improving asthma symptoms and bronchial responsiveness, their mechanism of action is unknown. We examined whether changes in bronchial responsiveness with corticosteroid therapy of asthma are accompanied by a reduction in cytokine gene expression and eosinophil infiltration in the airways. Bronchoalveolar lavage (BAL) was performed in 18 patients with moderate asthma before and after 2 wk of treatment with prednisolone, 0.6 mg/kg/day, or matched placebo in a randomized double-blind parallel group study. Cells were counted in BAL cytocentrifuge preparations, and the numbers of cells expressing cytokine mRNA were assessed by in situ hybridization using 35S-labeled RNA probes. When the actively treated and placebo groups were compared, there was a decrease in airway methacholine responsiveness (p < 0.01) after prednisolone. This was accompanied by a decrease in bronchoalveolar lavage eosinophils (p < 0.05), a reduction in the numbers of BAL cells per 1,000 expressing mRNA for interleukin-4 (IL-4, p < 0.01) and interleukin-5 (IL-5, p < 0.005), and an increase in numbers of cells expressing mRNA for interferon-gamma (p < 0.005). These results are compatible with the hypothesis that the beneficial effects of corticosteroids in asthma may result from modulation of cytokine production, with consequent inhibition of local bronchial eosinophilia.

Adult↗
PubMed1993

Measurement of alpha-fetoprotein, carcinoembryonic antigen and prostate-specific antigen in serum and heparinised plasma by enzyme immunoassay on the fully automated serono SR1 analyzer.

This paper describes the new enzyme immunoassays for the measurement of alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA) and prostate-specific antigen (PSA) in serum and heparinised plasma as developed for the fully automated Serono SR1 analyzer. Each assay incorporates two monoclonal antibodies in an immunoenzymetric sandwich format using alkaline phosphatase as the label and magnetic solid phase separation. All processing steps are performed by the SR1. The assays have good analytical performance with respect to detection limits (typically 0.24 microgram/l, 1.0 microgram/l and 0.1 microgram/l respectively for AFP, CEA and PSA), precision (within and between run CVs less than 7 and 12% respectively) and recovery of added analyte (100 +/- 10%). Regression analysis of linearity on dilution gives correlation coefficients (r) of 0.9984-1.0000. Tumour marker concentrations measured with these assays are in good agreement with concentrations determined by established immunoassays (r > 0.96). Values measured in samples of healthy probands and samples of patients with malignant and non-malignant diseases are as would be expected for clinically valid assays. The study demonstrates that the measurement of AFP, CEA and PSA in serum and heparinised plasma on the fully automated SR1 analyzer is suitable for the clinical diagnosis, monitoring and management of certain cancers and, in the case of AFP, for prenatal screening of maternal serum.

Adult↗
PubMed1993

Audit in the management of gliomas.

A retrospective study of 139 glioma patients was conducted in an effort to audit management. Factors affecting survival were studied using a Cox Proportional Hazard Model. These factors included age, sex, location, grade, type of surgery, use of radiotherapy, presenting symptoms, Karnofsky score on admission and Karnofsky score 3 months following surgery. Lower grade, high Karnofsky score on admission, radiotherapy and frontal location were associated with better survival. There was statistically insignificant evidence that the other factors had an influence on survival. Patients presenting with a poor neurological score were treated with burrhole biopsy alone. Only 10% of these patients survived more than 6 months. On the other hand, 26% of patients who had craniotomy on the basis of reasonable clinical status lived less than 6 months. Sixty-six per cent of patients in this craniotomy group were aged 60 years or over, and 66% of those aged over 60 had a Karnofsky score of less than 70. We conclude that careful judgement is required before subjecting patients aged over 60, especially those with a low Karnofsky score, to radical therapy.

Adolescent↗
PubMed1993

Fitness in a U.K. screening sample--a comparison with the Canadian population.

Fitness measurements were compared from approximately 12,000 men and 5,000 women attending the BUPA Health Screening Centre, London, with published Canadian levels. The mean (+/- SD) predicted VO2-max values in the BUPA group were 35.1 (+/- 9.2) and 30.0 (+/- 8.4) ml/kg/min for men and women aged 15-64 years, respectively. These compare with means of 44.1 and 34.3 in men and women of the same age in Canada. A comparison of flexibility measurements showed that in all age groups the BUPA subjects were less flexible than their Canadian counterparts, on average 28.7% and 25.1% lower for men and women, respectively. Comparison of grip strength showed BUPA values to be on average 8.1% lower in men and 9.5% lower in women than the Canadian levels. Analysis of variance showed that the fitness measurements reflect the recorded physical activity in the BUPA sample, and in particular the predicted VO2-max and flexibility exhibit linear relationships with age and exercise levels.

Adolescent↗
PubMed1993

Defining normality--art or science?

The problem of defining normality, and in particular the establishment of reference ranges, is discussed. A so-called "objective" method of determining such ranges is described. It is suggested, however, that all currently used methods for defining "normal" ranges rely ultimately on a subjective choice. We propose the use of "How Often That Happens" (HOTH) graphs as an alternative to the conventional reference range. Such graphs show the frequency of results at least as extreme as any observed value. We have used such graphs, along with computer simulation models, in an attempt to describe how the frequency distribution of a given parameter changes as a population ages. Finally, an analogy is drawn between the states of "health", "illness" and "death", and the attractors which arise in non-linear dynamic systems. We conclude that the definition of normality is in fact more of an art than a science.

Adult↗
PubMed1993

Bone density, biochemistry and life-style.

We have assessed the relationship between bone density, biochemistry and life-style factors in a cross-sectional study of 434 pre- and 357 postmenopausal women. Bone-mineral content (BMC) was measured in the non-dominant forearm using single-photon densitometry. Bone mass was corrected for bone size (BMC2) in a sub-set of 263 subjects. Correlation statistics and multiple regression analyses were used to identify physical and biochemical measurements that could be used to best predict BMC or BMC2. These were combined with lifestyle factors, using multiple logistic regression analysis, to identify women at risk of low bone density. Cut-off values were taken as the 5th percentile of the bone density distributions in pre-menopausal women. In postmenopausal women, using BMC2 values to define "risk", and using age, creatinine, alkaline phosphatase, thyroxine treatment, and calcium supplementation as predictors, a sensitivity of 73% and a specificity of 95% were achieved. Such a model may be of use as a "first pass" screening test for osteoporosis.

Adult↗
PubMed1993

Implants composed of carbon fiber mesh and bone-marrow-derived, chondrocyte-enriched cultures for joint surface reconstruction.

The current study integrates two distinct approaches in joint resurfacing into a combined type of implant, composed of carbon fiber mesh impregnated and coated with a hyaluronic-acid-based delivery substance containing cultured cells. Rabbit autogeneic chondrocyte-enriched cultures obtained from mesenchymal stem cells (chondroprogenitor cells) derived from adult rabbit bone marrow were grown in vitro under conditions favoring chondrogenesis. The improvement in quality of repair when a combined implant containing both cells and a carbon scaffold was used, in comparison to the utilization of carbon fiber mesh alone, was clearly demonstrated using clinical, histological, biochemical, and biomechanical examinations. Evaluations of the joints were performed at 6 weeks and 6 months after implantation. The repair tissue in the cell-implanted joints consisted of a typical hyaline cartilage, which was more cellular and thicker than the repair tissue in the hyaluronic-acid-impregnated carbon-fiber-implanted control joints. The hyaline cartilage in the experimental group formed a superficial layer above the carbon fibers, flush with the joint surface. In the controls, in which carbon fiber and the delivery substance alone were implanted, a histologically and biochemically fibrous tissue that was inferior biomechanically to the new cartilage was formed by the cells containing implants.

Animals↗
PubMed1993

Bone density in old chickens' metaphyses, as affected by local trauma and chondrocyte implantation.

Resurfacing of joints by chondrocyte implants often leads to an increased subchondral bone density. To further evaluate this phenomenon, this study analyzed bone density and bone formation in three groups of 3-year-old chickens (90 animals, 30 per group): (1) implantation of chondrocytes embedded in hyaluronic acid (HA) into the tibial metaphysis; (2) implantation of delivery substance only; (3) sham-operated control group. Results were assessed biochemically, histologically, and histomorphometrically at 6 weeks and 6 months postimplantation. A 1.5-fold increase in the metaphyseal bone density was observed in the HA-implanted controls, as compared to sham-operated/normal joints. A further increase in bone density to twice the density of the sham-operated joints was achieved by implantation of chondrocytes. In bones implanted with cells, long-lasting (6 weeks) cartilage nodules were observed, which eventually underwent hypertrophy. The implanted chondrocytes were surrounded by a dense inflammatory infiltrate, which did not prevent the induction and formation of new bone. Based on these findings, it was concluded that chondrocyte implantation into bones results in an increase in local bone density due to a prolonged process of endochondral ossification. Further studies are necessary to evaluate the possible application of this implantation procedure in osteoporosis.

Animals↗
PubMed1992

Public health heresy.

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Public Health Administration↗
PubMed1992

Polymorphisms in the apolipoprotein (apo) AI-CIII-AIV gene cluster: detection of genetic variation determining plasma apo AI, apo CIII and apo AIV concentrations.

We have examined the associations between levels of plasma apolipoprotein (apo) AI, apo CIII and apo AIV and genetic variation in the apo AI-CIII-AIV gene cluster in 162 boys and young men from Belgium aged from 7 to 23 years. Genotypes were determined for six restriction enzymes XmnI, PstI, SstI, PvuIIA-CIII, PvuIIB-AIV and XbaI, and for the G to A substitution at -75 bp in the 5' region of the apo AI gene. The polymorphism most strongly associated with apo AI levels was the G to A substitution (P = 0.025, R2 x 100 = 3.6%) confirming previous observations. The polymorphism most strongly associated with apo CIII levels was that of PvuIIA-CIII (P = 0.023, R2 x 100 = 2.9%) in the apo CIII gene. This novel association must be interpreted with caution until it has been confirmed in an independent sample. The polymorphism associated with the largest effect on apo AIV levels was that detected with XbaI in the apo AIV gene, but this association was not statistically significant. Previously reported associations between the SstI polymorphism and triglyceride levels, and between the PstI polymorphism and apo AI levels, were weakly detected in the present sample. Our results show that variation associated with some of the polymorphisms in the apo AI-CIII-AIV cluster makes a small, but statistically significant, contribution to the determination of apo AI and apo CIII levels in this sample of young men and boys. These observations may, in part, explain reported associations between polymorphisms in this gene cluster, differences in plasma lipid and lipoprotein levels, and prevalence of coronary artery disease.

Adolescent↗
PubMed1992

A family with X-linked deafness showing linkage to the proximal Xq region of the X chromosome.

Linkage analysis has been carried out in a family with severe congenital sensorineural deafness with a structural abnormality of the inner ear. Recombinations show the gene responsible for deafness in this family to lie between the loci DXS255 (Xp11.22) and DXS94 (Xq22). Close linkage was found to locus DXS159 (cpX289) in Xq12, with a LOD score of 3.155 and 0 recombination. This location is consistent with other linkage studies of X-linked deafness.

Chromosome Mapping↗
PubMed1992

Physical fine mapping of genes underlying X-linked deafness and non fra (X)-X-linked mental retardation at Xq21.

Linkage studies and cytogenetically visible deletions associated with nonspecific X-linked mental retardation (XLMR) and a specific form of deafness (DFN3) have indicated that the genes responsible for these disorders are located at Xq21. Using DNA probes from this region, we have studied several overlapping deletions spanning different parts of Xq21. This has enabled us to assign the DFN3 gene and a gene for nonspecific XLMR to an interval that encompasses the locus DXS232 and that is flanked by DXS26 and DXS121.

Adolescent↗
PubMed1992

Neuropeptidergic innervation of intramuscular hemangiomas.

Intramuscular hemangiomas are idiopathic lesions which are either tumoral or developmental in origin. A close association of abnormal blood vessels with nerve fibers is found and may suggest that nerves have a primary inciting role in the development of these lesions. In the current study, the number of nerve fibers in different zones around the tumors, as well as the type of neuropeptides present in these fibers, was quantitatively assessed by computer-assisted image analysis of immunohistochemical staining of histological slides. The number of nerve fibers as determined by positive staining by anti-protein S-100 antibodies was found to be elevated in the immediate vicinity of the abnormal blood vessels. The density of the nerve fibers rapidly declined with increasing distance from the hemangiomas, reaching normal values at distances of over 2 mm. Furthermore, hemangiomas contain a significantly higher number of calcitonin gene-related peptide (CGRP), substance P, and Met-enkephalin-positive fibers. The most significant rise in number is that of CGRP-positive fibers. This neuropeptide is a known mitogen, which could be responsible for the growth of the hemangiomatous blood vessels. Substance P is a nociceptive neurotransmitter and its presence can explain the pain which often accompanies even tiny intramuscular hemangiomas.

Adolescent↗
PubMed1992

Seasonal variation in serum cholesterol levels--evidence from the UK and Japan.

Using data from 140,000 men and 32,000 women in the UK and 30,000 men and 12,000 women in Japan, we performed spectral analyses to test for seasonal variation in serum cholesterol levels. In both countries and both sexes we found a strong seasonal effect, cholesterol levels being some 3-5% higher in winter than in summer. This was independent of seasonal changes in body mass. Mean monthly cholesterol levels were negatively correlated with mean monthly air temperatures (r = -0.60 to -0.71). The observed seasonal differences were larger than the inter-assay coefficient of variation for the cholesterol determination method employed and have important consequences for long-term epidemiological or intervention studies.

Cholesterol↗