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P Emery

Publications and source records attributed to P Emery.

At least 271 records · Page 15Linked to original sources
PubMed1993

RFX1 is identical to enhancer factor C and functions as a transactivator of the hepatitis B virus enhancer.

Hepatitis B virus gene expression is to a large extent under the control of enhancer I (EnhI). The activity of EnhI is strictly dependent on the enhancer factor C (EF-C) site, an inverted repeat that is bound by a ubiquitous nuclear protein known as EF-C. Here we report the unexpected finding that EF-C is in fact identical to RFX1, a novel transcription factor previously cloned by virtue of its affinity for the HLA class II X-box promoter element. This finding has allowed us to provide direct evidence that RFX1 (EF-C) is crucial for EnhI function in HepG2 hepatoma cells; RFX1-specific antisense oligonucleotides appear to inhibit EnhI-driven expression of the hepatitis B virus major surface antigen gene, and in transfection assays, RFX1 behaves as a potent transactivator of EnhI. Interestingly, transactivation of EnhI by RFX1 (EF-C) is not observed in cell lines that are not of liver origin, suggesting that the ubiquitous RFX1 protein cooperates with liver-specific factors.

Animals↗
PubMed1993

Assessment of lupus: where are we now?

Decisions about treatment for patients with SLE are based on numerous criteria, including the rate of change of clinical features and disease markers (especially antibodies to dsDNA and markers of complement turnover), which organ systems are affected, the severity of manifestations, and the presence of pre-existing damage (which may reduce the reserve capacity of the organ system). Most of the currently available organ systems calculate a single overall score, at a single point in time, and take few of these considerations into account. SLAM is the only index to consider directly the scoring of severity as well as activity, though this concept is probably inherent in most of the other indices because of various methods for weighting the scores. Preliminary studies have indicated that four of the scales (BILAG, SLAM, LAI, and SLEDAI) are sensitive to change. Few of the indices have been tested longitudinally, hence their role in clinical trials remains to be established. None of the indices considers the impact of damage, indeed this is not their remit, but this concept is being considered by an international working group. Outcome in SLE has been shown to be determined by, among other things, the number of exacerbations and the presence of renal or neurological disease. It would seem, therefore, important to measure disease activity in designated organ systems, which most of the indices fail to do. The inclusion of immunological tests in some scales (for example, SIS, SLEDAI, LAI) makes them unsuitable for use as instruments to validate immunological or other scatological markers. Furthermore, given the heterogeneity of disease manifestations in SLE, and evidence linking scatological abnormalities with specific clinical manifestations, it is perhaps naive to expect a new scatological test to correlate strongly with overall disease activity. Three of the currently available activity scales have been shown to be reliable, both between and within raters (BILAG, SLAM, SLEDAI). The lack of a 'gold standard' for measuring disease activity in SLE makes it difficult to be sure that these scales are actually measuring what they are supposed to be measuring (criterion validity), but they do correlate strongly with each other in cross sectional studies, suggesting that they are, at least, all measuring the same thing (convergent validity). Convergent validity for these instruments used longitudinally remains to be established, particularly for patients with very active disease. In conclusion, measurement of disease activity in SLE is central to patient care, and a number of instruments are available fro this purpose. Although none is perfect, most are reliable and valid, and are suitable for classifying and monitoring groups of patients in the research setting. In reality, the indices are used with the additional benefit of laboratory markers and, as yet, no one has found the instruments sufficiently sensitive and specific to rely entirely upon them. The exact choice of instrument should be governed by the purpose for which it is required in clinical practice. Disease activity scales are unlikely to be appropriate for dictating treatment decisions in individual cases. An instrument which would be comprehensive and flexible enough for this purpose would necessarily prove too complicated and cumbersome for widespread use.

Acute Disease↗
PubMed1993

Modified suprascapular nerve block with bupivacaine alone effectively controls chronic shoulder pain in patients with rheumatoid arthritis.

Chronic shoulder pain is a common and disabling symptom in patients with rheumatoid arthritis (RA). It has been previously shown that a suprascapular nerve block (SSNB) using the standard mixture of bupivacaine and adrenaline (Ba) plus methylprednisolone (P), which is routinely used in pain clinics, results in a considerable improvement in pain relief and range of movement compared with conventional intra-articular steroid injections in such patients. A double blind study was carried out in 29 patients (58 shoulders) with RA to compare SSNB induced with Ba alone with that induced using the conventional mixture of Ba plus P. Highly significant improvements were noted in measures of pain, stiffness, and range of most movements for both treatments (up to three months) compared with baseline. Results favoured Ba alone; the differences between the two treatments reached statistical significance for stiffness (at 12 weeks) and active abduction (at one week). It is concluded that the addition of P to the SSNB mixture confers no benefit in these patients.

Adult↗
PubMed1993

Relapses in patients with a systemic vasculitis.

Treatment with cyclophosphamide and steroids has greatly improved survival in patients with systemic necrotizing vasculitis but does not always provide a complete cure. There are as yet few data on the incidence, pattern and outcome of relapses in these diseases. We studied relapses in 150 consecutive patients with an idiopathic necrotizing vasculitis: 12 with classical polyarteritis (CPAN); 95 with microscopic polyarteritis (MPA); 28 with Wegener's granulomatosis (WG); and 15 with limited Wegener's granulomatosis (LWG). The relapse rates and median time to relapse in months were: CPAN, 41.7%/33; MPA, 25.4%/24; WG, 44%/42; LWG, 52%/18. The clinical features of relapse were similar to or more aggressive than those of the original presentation in CPAN and LWG and included renal disease for the first time, but in MPA and WG, relapse involved less renal involvement in the majority of cases. Laboratory tests, although often positive at relapse, were unhelpful in its prediction. The considerable accumulative non-fatal relapse rate contrasts with the very good long-term survival rates, and confirms the importance of long-term follow-up in systemic vasculitis.

Adult↗
PubMed1993

Monotherapy in rheumatoid arthritis.

In the past few years there has been considerable debate regarding the optimal therapy for patients with RA. The arguments have been phrased in a variety of ways and frequently involve the concept of therapy with multiple drugs. The underlying assumption is that current therapy is inadequate and that the whole therapeutic approach to RA needs rethinking. The evidence on which these assumptions are made is reviewed here. Additionally, this paper argues for a more discriminating approach using prognostic indicators to identify the minority of patients with persistent unresponsive disease (and poor outcome) for whom more aggressive therapy should be reserved.

Anti-Inflammatory Agents↗
PubMed1992

Genetically determined factors as predictors of radiological change in patients with early symmetrical arthritis.

OBJECTIVE: To determine whether genetic factors associated with established rheumatoid arthritis could, in combination with rheumatoid factor, predict the development of radiological erosions in patients with early symmetrical (rheumatoid-like) arthritis. DESIGN: Prospective study. SETTING: Teaching hospital, early arthritis clinic. SUBJECTS: Forty nine patients with symmetrical polyarthritis attending the early arthritis clinic. MAIN OUTCOME MEASURES: Conserved sequence of DR beta third allelic hypervariable region, sulphoxidation capacity, rheumatoid factor, and development of radiologically determined bone erosions. RESULTS: None of the 49 patients had radiological erosions at presentation but 25 developed these by four years. Patients with the conserved class II major histocompatibility complex (third allelic hypervariable of DR beta 1) genes associated with rheumatoid arthritis had a relative risk for the development of erosions of 1.9 (95% confidence interval 0.8 to 4.5). For poor sulphoxidation the risk was 2.5 (1.1 to 5.6) and for the presence of rheumatoid factor 1.8 (0.9 to 3.7). Of the 33 patients who had two or three of these risk factors, 24 developed erosions, with a relative risk of 11.6 (1.7 to 78.5) compared with only one of the 16 individuals with no or one risk factor. CONCLUSIONS: This preliminary study shows that by using these stable markers it is possible to make clinically useful predictions of outcome in patients with early symmetrical inflammatory arthritis.

Acute-Phase Reaction↗
PubMed1992

Abnormal sulphur oxidation in systemic lupus erythematosus.

S-carboxy-L-methylcysteine was used to assess the activity of the S-oxidation pathway of sulphur metabolism in 35 patients with systemic lupus erythematosus (SLE); 25 (71%) showed impaired sulphoxidation and 21 (60%) produced virtually no sulphoxides, compared with 17 (36%) and 2 (4%), respectively, of 47 healthy controls. The substrate/product ratio of cysteine oxygenase (plasma cysteine/sulphate) was significantly higher in SLE patients than in controls (median [interquartile range] 362 [224-588] vs 65 [44-111]; p less than 0.00001). The alternative pathway of sulphur metabolism, S-methylation, catalysed by thiolmethyltransferase, was not impaired in the SLE patients. There is a biochemical difference in sulphur metabolism between SLE and rheumatoid arthritis, since both pathways are impaired in the latter disorder.

Adult↗
PubMed1992

Management of early inflammatory arthritis. Genetic factors predicting persistent disease: the role of defective enzyme systems.

In this chapter, we investigate the use of non-toxic 'probe drugs' to give information about basic biochemical pathways. We have examined the hypothesis that a major factor in RA is defective metabolism of sulphur-containing compounds. At least two pathways have been shown to be abnormal in RA. Generally, patients have reduced capacity to metabolize and detoxify thiol compounds by methylation, and have increased levels of plasma cysteine. They also have a lower capacity for S-oxidation of cysteine and its derivatives, with reduced amounts of plasma sulphate. The raised cysteine resulting from less effective metabolism may lead to reduced clearance of immune complexes and a raised inflammatory response in RA patients. Lower plasma sulphate, however, leads to defective tissue synthesis, and makes adequate repair of damaged joints less feasible. The co-existence of defects in these two interacting endogenous pathways serves to perpetuate the disease process, leading to chronic inflammation and tissue destruction. These enzyme defects have been shown to be predictive of persistent disease.

Acetaminophen↗
PubMed1992

Genetic factors influencing the outcome of early arthritis--the role of sulphoxidation status.

A minority of individuals have an impaired ability to oxidize sulphur. An increased prevalence of this poor S-oxidation capacity has been observed in patients with established rheumatoid arthritis (RA). The role of this enzyme system in the development of disease was studied by testing the S-oxidation capacity of 54 patients with recent onset symmetrical poly-arthritis, who were followed up at 1 and 4 years. Those patients with persistent disease at 1 year had a prevalence of poor S-oxidation of 69%. At 4 years 74% of those with a diagnosis of RA were poor S-oxidizers compared to 31% of those who were asymptomatic (P less than 0.01). A defective ability to oxidize sulphur appears to predispose to persistent clinical disease.

Arthritis, Rheumatoid↗
PubMed1992

Increased prevalence of poor sulphoxidation in patients with rheumatoid arthritis: effect of changes in the acute phase response and second line drug treatment.

A minority of normal subjects have an impaired ability to oxidise sulphur, which is associated with an increased risk of side effects when they receive sulphur containing drugs. In 114 patients with rheumatoid arthritis a greatly increased prevalence of poor sulphoxidation was found in 82 (72%) patients compared with 70/200 (35%) healthy controls, 45/121 (37%) controls matched for age, and 4/35 (11%) of the normal aged general population. In a longitudinal study of 37 patients there was no significant alteration in sulphoxidation status after the introduction of a second line drug or with marked changes in the acute phase response. It seems, therefore, that the poor sulphoxidation status in patients with RA is not an epiphenomenon and may be an important factor in determining the clinical features of rheumatoid disease.

Acute-Phase Reaction↗
PubMed1992

Damage to the endothelium in Sjögren's syndrome: lack of correlation with antinuclear antibody titre and presence of antibodies to SSA or SSB autoantigens.

Serum levels of von Willebrand factor antigen (as an index of damage to the endothelium) and tissue antinuclear antibodies and antibodies to SSA (Ro) (which have been associated with vasculitis) and SSB (La) autoantigens were measured in patients with Sjögren's syndrome. Although high levels of all indices were recorded, there were no intercorrelations. This provides evidence that although tissue autoantibodies may be useful in confirming a diagnosis, they have no place in the pathological course of the disease and so may be an epiphenomenon.

Antibodies, Antinuclear↗
PubMed1992

Antibodies to protein P in systemic lupus erythematosus.

A synthetic peptide was used to develop an enzyme linked immunosorbent assay (ELISA) to detect antibodies to the ribosomal proteins P0, P1, and P2. Significantly increased levels of IgG antibodies to protein P were found in 16% (18/116) of patients with systemic lupus erythematosus but slightly increased levels were detected in 2% (2/98) of patients with rheumatoid arthritis and one normal control subject. No association was observed between the presence of IgG antibodies to protein P and either lupus psychosis or depression. Sequential studies in individual patients failed to show an association between antibody levels and the development of psychosis.

Antibodies↗
PubMed1992

Nabumetone compared with naproxen in the treatment of rheumatoid arthritis: a multicenter, double blind, randomized, parallel group trial in hospital outpatients.

In this double blind, randomized, parallel group study, 298 patients with rheumatoid arthritis received nabumetone (2000 mg/day) or naproxen (1000 mg/day) for 3 months. At the end point, nabumetone treated patients exhibited significant improvement in pain, Ritchie articular index, and duration of morning stiffness when compared to baseline. In contrast, naproxen treated patients showed significant improvement only in Ritchie articular index. Nabumetone was significantly more effective than naproxen for pain relief. More nabumetone treated patients withdrew due to lack of efficacy than naproxen treated patients. However, nabumetone was better tolerated than naproxen because fewer patients withdrew for adverse events or experienced severe adverse events, and significantly fewer patients required treatment for adverse events.

Adult↗