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Biomedical subjects

J Taylor

Publications and source records attributed to J Taylor.

At least 19 recordsLinked to original sources
PubMed1992

Immunisation with canarypox virus expressing rabies glycoprotein.

Poxviruses have many useful features as vectors for genes that carry immunising antigens from other viruses, such as ease of production and induction of cellular and humoral immunity, but there is concern about the safety of vaccinia virus. We turned to an avian poxvirus (canarypox); this virus undergoes abortive replication in mammalian cells that enables presentation of early gene products to the immune system. Canarypox virus was used as a vector for the rabies glycoprotein G gene. The safety and efficacy of the recombinant (ALVAC-RG; vCP65) were tested in several animal species, then it was subjected to a phase 1 clinical trial. Twenty-five volunteers were randomly assigned to subcutaneous injections of the recombinant (three groups [A, B, and C] received two doses each of 10(3.5), 10(4.5), and 10(5.5) tissue-culture infectious doses50, respectively) or of human diploid cell culture vaccine (HDC; 6.52 international potency units per dose). 28 days after the second dose, all nine ALVAC-RG group-C subjects and two of three group-B subjects had rabies neutralising antibody concentrations of at least 0.5 IU/ml, the level associated with protection in animals. Although the geometric mean titre of these antibodies at that time was lower in group C than in the ten HDC recipients (4.4 [range 0.9-12.5] vs 11.5 [4.7-25.3] IU/ml), a single booster dose at 6 months induced a recall response in volunteers primed with either vaccine. Side-effects associated with ALVAC-RG were mild and of short duration and occurred at similar frequency to those of HDC vaccine. This study has shown the potential of non-replicating poxviruses as vectors for vaccination in human beings. Trials of canarypox-virus recombinants at higher doses and by other routes of administration are needed.

Adult↗
PubMed1992

Evidence for regulatory genes on mouse chromosome 7 that affect the quantitative expression of proteins in the fetal and newborn liver.

A series of deletions around the albino locus on mouse chromosome 7 is believed to include one or more regulatory genes that control the activities of a cluster of liver enzymes. To further characterize the functions of this region of the mouse genome, we have used quantitative two-dimensional electrophoresis to analyze the effects of two of these deletions, c3H and c14CoS, on the expression of liver proteins. More than 400 distinct protein gene products were quantitated in livers from fetal and newborn wild-type homozygous (cch/cch), heterozygous (cch/c3H or cch/c14CoS), and deletion homozygous (c3H/c3H or c14CoS/c14CoS) mice. Livers of fetal and newborn c3H heterozygotes and homozygous wild-type littermates produced qualitatively identical protein patterns after two-dimensional electrophoresis. In livers of c3H homozygous fetuses, however, abnormal amounts (either increased or decreased relative to homozygous wild-type and heterozygous littermates) of 29 proteins were found. Twenty-eight of these 29 protein anomalies were also found in livers of newborn c3H homozygotes. Livers of fetal and newborn mice homozygous for the c14CoS deletion, which overlaps the c3H deletion and produces a similar phenotype, expressed normal amounts of these proteins. One of the 29 proteins (MSN807) has an amino-terminal sequence similar to a 23-kDa translationally controlled protein abundant in mouse erythroleukemia and sarcoma-180 cells. These results suggest that normal chromosome 7 contains genes, located within the region of the c3H but not the c14CoS deletion, that regulate the abundance of specific proteins in the liver. These proteins cannot be related to the phenotypic alterations shared by the c3H and c14CoS deletions.

Albinism↗
PubMed1992

Mouse liver protein database: a catalog of proteins detected by two-dimensional gel electrophoresis.

Alterations in the abundance or structure of mouse liver proteins are being studied using two-dimensional gel electrophoresis (2-DE) to build a database of protein changes correlating with exposure to ionizing radiation or toxic chemicals. Thus far, studies have included the analysis of proteins from the offspring of exposed parents or from the exposed individuals themselves. In order to characterize and identify proteins found altered by such exposures, sex- and strain-related differences in protein patterns have been analyzed, and the subcellular locations of a large portion of the mapped proteins have been determined. As part of these studies, data are collected and stored using a variety of computer hardware and software tools that allow the accumulation of information on the origin of samples, gel identification, experiment description, and protein similarities and differences. This accumulation of information constitutes the mouse liver protein database. Relational database software is used to tie the different facets of the database together so that the results of a variety of experiments can be compared and interrelated. The database optimizes the information obtained from 2-DE gel sets by allowing use of the data for many purposes, including monitoring of gel resolution to ensure the collection of high quality data and correlation of protein effects induced by different agents. This first edition of the Argonne National Laboratory mouse liver protein database lays the foundation for future work and communication that should elucidate the significance of observed protein effects as possible markers of exposure to toxic agents.

Animals↗
PubMed1992

Use of principal components analysis for mutation detection with two-dimensional electrophoresis protein separations.

The application of two-dimensional electrophoresis (2-DE) to mutation detection requires the capability to monitor each protein in a 2-DE pattern for significant changes in abundance indicative of a mutation event. Previously, mutation searches were done using a univariate outlier detection method in which each protein spot was considered independently in a classical outlier search. An alternative approach to analysis of 2-DE patterns for quantitative changes is a multivariate procedure which takes advantage of the observation that protein spots in a 2-DE pattern often represent correlated rather than independent measurements. We have compared the efficiency of univariate and multivariate procedures for mutation detection using data from the Argonne National Laboratory 2-DE database of mouse liver proteins. Analyses involving a total of over 1500 gels were performed to compare the performance of a multivariate method based on principal components analysis (PCA) with the univariate method. Up to 279 spots from each pattern were used for PCA. First, a simulation was performed to assess the detection efficiency of PCA for single protein spots decreased in abundance by 50%. Then, the ability to detect actual mutations was tested using eight confirmed mutations. Results show that, compared to a univariate approach to analysis of data from the mouse model system, the multivariate method increases the number of protein spots on each 2-DE pattern that can be monitored for quantitative changes indicative of mutations by compensating for variables that contribute to the background quantitative variability of protein spots.

Animals↗
PubMed1992

Terodiline causes polymorphic ventricular tachycardia due to reduced heart rate and prolongation of QT interval.

Recent reports have suggested an association between terodiline hydrochloride and cardiac arrhythmias. We report 4 patients presenting over a six month period who developed polymorphic ventricular tachycardia (polymorphic VT) while receiving treatment with this agent. In each case there was prolongation of QT interval on electrocardiogram (ECG). Two patients had hypokalaemia associated with diuretic therapy. In the 3 cases in which follow-up ECG was available, QT interval returned to normal after discontinuation of terodiline. In order to define the effects of terodiline on corrected QT interval (QTc) and heart rate in the elderly, a prospective study was performed in 8 elderly in-patients treated with terodiline for urinary incontinence. After 7 days treatment with terodiline 12.5 mg twice daily, there was a significant increase in QT by a mean of 29 ms, QTc by 15 ms and a decrease in resting heart rate by a mean of 6.7 beats.min-1. Terodiline increases QTc and reduces resting heart rate in elderly patients. Both these effects may be associated with polymorphic VT, a potentially life threatening arrhythmia. This drug should be avoided in patients with other known risk factors for polymorphic VT, particularly hypokalaemia and cardiac disease.

Aged↗
PubMed1992

Dipyridamole increases human red blood cell deformability.

An automated filtration technique has been used to investigate the effect of dipyridamole (DP) on red blood cell deformability in patients identified as having rigid red cells. They were patients on haemodialysis (HD) for chronic renal failure (n = 18), patients with peripheral vascular disease (PVD, n = 23) and controls (hospital outpatients, n = 33). Leucocytes and platelets were removed from heparinised blood by filtration through Imugard wool. Washed red cell suspensions in buffer at 5% haematocrit, without or with 5 microM DP, were filtered through Nuclepore Hemafil Membranes with 4.7 microns pores. The initial steady state relative filtration pressure (iRFP) was used to assess cell deformability. A low iRFP value reflects increased deformability and vice versa. The mean iRFP values were 0.33, 0.393 and 0.403 for controls, PVD and HD patients respectively, indicating that the red cells in the two groups of patients were significantly more rigid. DP reduced the iRFP to 0.266, 0.278 and 0.263 for controls, PVD and HD patients respectively. The results suggest that DP may be beneficial when red cell rigidity contributes to impaired microvascular perfusion.

Adult↗
PubMed1992

Nonreplicating viral vectors as potential vaccines: recombinant canarypox virus expressing measles virus fusion (F) and hemagglutinin (HA) glycoproteins.

The development of canarypox virus (CPV) recombinants expressing the hemagglutinin (HA) and fusion (F) glycoproteins of measles virus (MV) is described. Inoculation of the CPV-MV recombinants into avian or nonavian tissue culture substrates led to the expression of authentic MVF and MVHA as determined by radioimmunoprecipitation and surface immunofluorescence. In contrast to avian-derived tissue culture, no productive replication of the CPV recombinant was evident in tissue culture cells derived from nonavian origin. On inoculation of dogs, a species restricted for avipoxvirus replication, the recombinants elicited a protective immune response against a lethal canine distemper virus (CDV) challenge. The level of MV neutralizing antibodies and the level of protection induced against CDV challenge achieved by the host-restricted CPV vector were equivalent to that obtained by vaccinia virus vectors expressing the same MV antigens.

Animals↗
PubMed1992

NYVAC: a highly attenuated strain of vaccinia virus.

A highly attenuated vaccinia virus strain, NYVAC (vP866), was derived from a plaque-cloned isolate of the Copenhagen vaccine strain by the precise deletion of 18 open reading frames (ORFs) from the viral genome. Among the ORFs deleted from NYVAC (vP866) are two genes involved in nucleotide metabolism, the thymidine kinase (ORF J2R) and the large subunit of the ribonucleotide reductase (ORF I4L); the gene encoding the viral hemagglutinin (ORF A56R); the remnant (ORF A26L) of a highly expressed gene responsible for the formation of A-type inclusion bodies; the disrupted gene (ORFs B13R/B14R) normally encoding a serine protease inhibitor; and a block of 12 ORFs bounded by two known viral host range regulatory functions (ORFs C7L through K1L). Within this block a secretory protein (ORF N1L) implicated in viral virulence and a functional complement 4b binding protein (ORF C3L) are encoded. The ORFs were deleted in a manner which prevents the synthesis of undesirable novel gene products. The attenuation characteristics of the derived NYVAC strain were compared in in vitro and in vivo studies with those of the Western Reserve (WR) laboratory strain, the New York City Board of Health vaccine strain (Wyeth), the parental plaque-cloned isolate (VC-2) of the Copenhagen vaccine strain used to derive NYVAC, and the avipox virus canarypox (ALVAC), which is naturally restricted for replication to avian species. The NYVAC strain was demonstrated to be highly attenuated by the following criteria: (a) no detectable induration or ulceration at the site of inoculation on rabbit skin; (b) rapid clearance of infectious virus from the intradermal site of inoculation on rabbit skin; (c) absence of testicular inflammation in nude mice; (d) greatly reduced virulence as demonstrated by the results of intracranial challenge of both 3-week-old or newborn mice; (e) greatly reduced pathogenicity and failure to disseminate in immunodeficient (nude or cyclophosphamide treated) mice; and (f) dramatically reduced ability to replicate on a variety of human tissue culture cells. Despite these highly attenuated characteristics, the NYVAC strain, as a vector, retains the ability to induce strong immune responses to extrinsic antigens.

Animals↗
PubMed1992

P300 and traffic scenes: the effect of temazepam.

The present research investigated the effects of a minor tranquillizer (temazepam) on P300 in a paradigm that may be relevant for traffic behaviour. Because accident scenes have not been used previously in P300 research, Experiment 1 (n = 8) examined whether the P300 elicited by safe traffic scenes and scenes of imminent road accidents were sensitive to the probability of occurrence. Event-related potentials were recorded from C3, Cz, C4, P3, Pz and P4 within an oddball paradigm. The type of stimulus to which subjects responded (pictures of imminent accidents or safe road scenes) was crossed with the probability (0.1 or 0.5) of the relevant (to which a response was required) event. The results indicated that P300 amplitude increased with decreasing probability of the relevant stimulus and that P300 was most pronounced at Pz. Experiment 2 (n = 12) employed a drug treatment (10 mg temazepam) and a placebo treatment (100 mg Vitamin E). An oddball paradigm with a probability of the relevant stimulus of 0.1 was used and P300 was recorded from Cz, C3, C4, Pz, P3 and P4. Generally, the ingestion of temazepam decreased P300 amplitude and increased P300 latency at all sites. Reaction time, on the other hand, was not influenced by drug administration. The data demonstrate the clear effect of minor tranquillizers on the psychological processes associated with P300.

Accidents, Traffic↗
PubMed1992

The image of self and of the environment in drug abusers: a comparative study using the TAT.

This study attempted to add to our understanding of the heroin abusers' identity problems, using images of the self and the environment. Murray's Thematic Apperception Test (TAT) was applied to a group of male drug users undergoing withdrawal treatment with methadone and also to a group of male, non-drug using controls. The needs of the subjects and the demands of the environment, plus interaction between the two, were compared between the two groups to obtain information about the self and lifestyle. Among the data which emerged, is an increased need for destructive aggression and an environment experienced as coercive and emarginating. Among the interactions we observed coerced imagination, difficulties in identification, personal relationships based on abandonment with persecutory projection of the female figure and a tendency toward immature defences such as avoidance, denial and acting out. This information is discussed in relation to possible means of treatment.

Adult↗
PubMed1992

Human leukocyte antigen-DRB1*1104 in the chronic iridocyclitis of pauciarticular juvenile rheumatoid arthritis.

To determine whether genetic markers for chronic iridocyclitis could be identified, we used both serologic and oligonucleotide dot blot techniques to characterize immunogenetically 164 children with early-onset pauciarticular juvenile rheumatoid arthritis. Seventy-eight children (47.6%) had chronic iridocyclitis and 86 (52.4%) had not had evidence of eye disease during a mean follow-up period after the onset of arthritis of 15.8 years (minimum of 5.5 years). Control subjects were 218 healthy, unrelated individuals. The analysis was limited to alleles known to be associated with an increased or decreased risk of early-onset pauciarticular juvenile rheumatoid arthritis or of chronic iridocyclitis in this form of juvenile rheumatoid arthritis. Only one split of human leukocyte antigen (HLA)-DR5, HLA-DRB1* 1104, showed a statistically significant association with a risk of chronic iridocyclitis (chi-square value = 7.52; p = 0.036 adjusted; odds ratio 3.45); HLA-DQA1* 0501 and HLA-DQB1* 0301, both in linkage disequilibrium with HLA-DRB1* 1104, also were significantly associated with eye disease. Patients with both the DRB1* 1104 and DPB1* 0201 genes had a 7.7-fold increased risk for chronic iridocyclitis compared with that for other patients. The presence of HLA-DRB1* 1104 was about four times as specific, but only about one third as sensitive, as antinuclear antibodies in identifying patients at risk for eye disease. Although all children with early-onset pauciarticular juvenile rheumatoid arthritis should undergo periodic slit-lamp examinations, those with the HLA class II gene DRB1* 1104 are at particularly high risk for eye disease, and we recommend that they be monitored carefully for its evolution.

Adult↗
PubMed1992

Resistance of hepatitis delta virus replication to interferon-alpha treatment in transfected human cells.

Interferon-alpha (IFN-alpha) is known to inhibit both DNA and RNA viruses, including hepatitis B virus (HBV). In humans the antiviral effect, if any, of IFN-alpha on hepatitis delta virus (HDV) is complicated by the fact that HDV is spread only to patients already infected with HBV. An in vitro model system was used to assay for an antiviral effect of IFN-alpha on HDV genome replication. Hep G2 cells were transfected with a plasmid containing a trimer of HDV and treated with IFN (20 or 100 units/mL) starting 1-7 days after transfection. RNA extracted from treated and nontreated cells was assayed by both slot blot and Northern analyses. The IFN-alpha treatment as expected increased the 2'-5' oligo A synthetase RNA activity, but it did not affect HDV genome replication. Thus, in the absence of HBV, it appears that HDV is resistant to IFN-alpha.

2',5'-Oligoadenylate Synthetase↗
PubMed1992

Evidence for reversibility of defective counterregulation in a patient with insulinoma.

To investigate her unheralded neuroglycopenia, a 45-year-old woman was studied before and 3 months after removal of her insulinoma. Hypoglycaemia was induced and reversed by glucose infusion during 4-h insulin infusions (1.5 mU kg-1 min-1). Postoperatively, the low preoperative adrenaline, noradrenaline, growth hormone, and cortisol responses increased by 490, 152, 64, and 178%, respectively, and started at higher glucose levels (2.7 vs 1.9 mmol l-1 for adrenaline), with a four-fold increase in autonomic symptoms and more profound psychomotor dysfunction. We conclude that the syndrome of recurrent severe hypoglycaemia with defective warning symptoms and hormonal responses, in this case induced by an insulin-secreting tumour, is reversible, perhaps by the removal of the hypoglycaemia, a finding which may be relevant to other patients with recurrent severe hypoglycaemia.

Blood Glucose↗