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Biomedical subjects

D J Wallace

Publications and source records attributed to D J Wallace.

At least 19 recordsLinked to original sources
PubMed1995

The elusive search for geographic clusters of systemic lupus erythematosus. Critical review.

OBJECTIVE: To ascertain whether there are any geographic clusters of systemic lupus erythematosus (SLE), and critically review 2 previous reports of these clusters. METHODS: A literature review of all epidemiologic surveys relevant to SLE published since 1966 was undertaken. This included a search of abstracts and reports, in addition to peer-reviewed publications. RESULTS: Two geographic clusters were identified in the literature. A report purporting that contaminated ground water in southwest Tucson, Arizona was associated with significantly increased symptoms of SLE was flawed since no patients were examined, discarded criteria were used, and incorrect definitions were employed by the nonrheumatologist authors. Another study, which identified a cluster in Nogales, Arizona, used generally valid methodology. However, the authors' conclusion that a 94/100,000 prevalence of SLE was evidence of an excessive increase in this 92% Hispanic/Native American community is not consistent with published surveys among Hispanic and Native American populations. CONCLUSION: No valid claims of SLE geographic clusters have been published.

Arizona↗
PubMed1995

Use of hyperbaric oxygen in rheumatic diseases: case report and critical analysis.

Hyperbaric oxygen has been used in patients with rheumatic disease for many years without reports of untoward or unusual complications for a variety of non-rheumatic indications. Recent evidence that hyperbaric oxygen inhibits the actions of certain cytokines, acts as an immune modulator and may help cognitive dysfunction has resulted in a re-examination of its potential role in rheumatic diseases. A case report of a lupus/scleroderma crossover patient is presented whose cognitive dysfunction improved after hyperbaric oxygen therapy. The history of hyperbaric oxygen and its physiology are related, along with a focused review of its effects on the immune and central nervous systems. Areas which might warrant further consideration by rheumatologists are outlined, as well as areas of concern.

Cognition Disorders↗
PubMed1994

Antibodies to histone (H2A-H2B)-DNA complexes in the absence of antibodies to double-stranded DNA or to (H2A-H2B) complexes are more sensitive and specific for scleroderma-related disorders than for lupus.

OBJECTIVE: To assess the role of antibodies to histones H2A, H2B, and anti-double-stranded DNA which form (H2A-H2B)-DNA complexes in patients with scleroderma-related disorders. METHODS: Antihistone antibodies were measured, by enzyme immunoassay, in 26 patients with scleroderma-related disorders, 100 patients with systemic lupus erythematosus (SLE), and 24 patients with rheumatoid arthritis. RESULTS: Antibodies to histone (H2A-H2B)-DNA complex were more commonly seen in patients with scleroderma-related disorders than in those with SLE (P < 0.0001). CONCLUSION: Scleroderma-related disorders should be included among conditions in which various types of antihistone antibodies are produced. A hypothesis to account for this finding is discussed.

Antibodies↗
PubMed1994

Systemic lupus erythematosus: considerations for a genetic approach.

There is a powerful evidence suggesting that etiology and pathogenesis of systemic lupus erythematosus has both genetic and environmental components. Unfortunately, understanding the genetics of lupus has been impeded by knowing the pattern of inheritance. Indeed, a complex mode of inheritance for the lupus disease phenotype is suggested by the known characteristics of this disorder. Twenty-five multiplex pedigrees for lupus have been enrolled and have been used to evaluate power to reveal linkage. The power to find linkage in these pedigrees is greater for autosomal recessive than for autosomal dominant modes of inheritance. Once 100 similar pedigrees are available for analysis our results predict that linkage is likely to be present for genetic models with relatively relaxed requirements. At loci operating by autosomal recessive inheritance linkage should be detectable despite genetic homogeneity as low as 40% and penetrance as low as 50%. For loci operating by autosomal dominant inheritance genetic homogeneity must be 60% or more when penetrance is as low as 50% to be able to establish linkage. Available preliminary data are also consistent with a possible genetic linkage of Fc gamma RIIIPMN with lupus in American Black pedigrees multiplex for lupus.

Alleles↗
PubMed1992

MARCKS protein is transcriptionally down-regulated in v-Src-transformed BALB/c 3T3 cells.

Activation of protein kinase C (PKC) by tumor-promoting phorbol esters leads to the phosphorylation of an 80-kilodalton PKC substrate (known as MARCKS) in murine fibroblasts. In BALB/c 3T3 cells stably transformed by v-Src, phorbol esters were unable to induce phosphorylation of MARCKS. Western blot analysis and in vitro kinase assays showed that both PKC protein levels and kinase activity were unchanged in v-Src-transformed relative to the parental nontransformed BALB/c 3T3 cells. However, MARCKS protein levels were reduced in v-Src-transformed cells relative to nontransformed cells. MARCKS RNA levels were also correspondingly reduced in v-Src-transformed cells. Nuclear "run-on" assays showed decreased transcription of MARCKS in v-Src-transformed cells. Thus, the absence of MARCKS in v-Src-transformed cells could be explained by a down-regulation of MARCKS transcription. Inhibiting the protein tyrosine kinase activity of v-Src with herbimycin A restored MARCKS RNA levels, MARCKS transcription, and MARCKS protein, suggesting that down-regulation of MARCKS in v-Src-transformed BALB/c 3T3 cells is a direct effect of v-Src.

3T3 Cells↗
PubMed1992

Cutaneous lupus erythematosus without systemic lupus erythematosus: clinical and laboratory features.

Sixty-seven patients with cutaneous lupus erythematosus (CLE) were followed up as part of a series of 570 lupus erythematosus patients seen in a private practice between 1980 and 1989. Clinical and laboratory features, treatment, and natural course were observed. Findings of interest included (1) a ratio of at least one CLE case for every seven cases of systemic lupus erythematosus (SLE); (2) occurrence of CLE in fewer women and apparently associated with an older age at diagnosis than SLE; (3) similar frequency of cutaneous lupus subsets in CLE and SLE; (4) strong family history for SLE but not CLE in CLE patients; (5) other cutaneous and musculoskeletal features in a majority of CLE patients and constitutional symptoms in 10%; (6) positive ANA titers, high sedimentation rates, and leukopenia common in CLE; (7) anticardiolipin antibody in 31% of CLE patients but not associated with systemic complications; (8) antimalarials required by 75% of patients and systemic steroids by 33%; and (9) an excellent prognosis associated with CLE, organ-threatening disease being rare.

Adult↗
PubMed1991

Elevated levels of endogenous IL-6 in systemic lupus erythematosus. A putative role in pathogenesis.

Elevated spontaneous IgG production is characteristic of SLE. To identify the factors that support it, IL-6, a cytokine with an important role in the differentiation of IgG-secreting cells, was studied in SLE patients. Higher than normal levels of IL-6 were found, by a B9 assay, in sera of 63 of 70 patients (p less than 0.05). IL-6 was detected in 36 of 37 active SLE sera in higher titers (p = 0.009) than those for inactive SLE (n = 33), which were higher (p less than 0.05) than healthy controls (n = 15). IL-6 mRNA was detected in freshly isolated PBMC of 11 of 11 patients but not in normal PBMC, whereas IL-1 mRNA was detected only in patients with active disease. IL-6 activity was recovered from PBMC of four SLE patients, but not from four normal donors. By immunoperoxidase, IL-6 was detected in the cytoplasm of SLE monocytes and lymphocytes. When SLE PBMC were grown in short term cultures with no deliberate stimulation, expression of the IL-6 gene declined rapidly. Accordingly, the spontaneous production of IgG by SLE PBMC could be enhanced by exogenous IL-6. Spontaneous IgG production was diminished by 20 to 65% in the presence of neutralizing antibodies to IL-6, TNF-alpha, or IL-1. In contrast, neutralization of endogenous IL-4 increased production by approximately 40%. Anti-TNF-alpha treatment decreased IL-6 content of PBMC cultures, whereas anti-IL-4 augmented it, and exogenous IL-6 reversed anti-TNF-alpha effects on IgG production. Therefore, it is possible that the neutralization of TNF-alpha and IL-4 affected IgG production by modulating the synthesis/activity of IL-6. These results support the concept that SLE B cell hyperactivity is promoted by dysregulation of endogenous cytokines and suggest that IL-6, in particular, has an important pathogenic role.

Blotting, Northern↗