Search PubMed⌕ Search

Biomedical subjects

C L Christian

Publications and source records attributed to C L Christian.

At least 37 records · Page 2Linked to original sources
PubMed1983

Induction of polymeric IgA rheumatoid factors in infective endocarditis.

IgA and IgM rheumatoid factor activity, circulating immune complex levels, and antinuclear antibodies were measured in 17 patients with subacute or chronic infective endocarditis. Approximately three fourths of these patients had both IgA and IgM rheumatoid factors detectable by radioimmunoassay, and IgA and IgM rheumatoid factor activity was strongly correlated (p less than 0.01). In three patients studied, IgA rheumatoid factor activity was predominantly polymeric as assessed by sucrose density ultracentrifugation (55 to 92 percent of total rheumatoid factor activity) and could bind radiolabeled secretory component. No correlations between rheumatoid factor activity and circulating immune complex levels or antibodies to nuclear antigens were observed. These observations indicate that circulating polymeric IgA antibodies do not necessarily signify a mucosal stimulus for IgA production and also demonstrate differences in the intensity and spectrum of autoantibody production when compared with autoimmune diseases.

Adult↗
PubMed1983

Prognostic and therapeutic implications of immunologic test results in rheumatic disease.

In systemic lupus erythematosus, some immunologic tests quantify disease activity, enable prediction of higher risk patterns of disease, and serve as therapeutic guides. In rheumatoid arthritis, serologic phenomena are significantly associated with more severe and sustained joint disease and with visceral manifestations (vasculitides and granulomas), but they have not been useful in monitoring the course of disease or response to therapy. In other rheumatic syndromes, a variety of antinuclear specificities show promise as marker antibodies, but their prognostic and therapeutic implications remain largely unexplored.

Arthritis, Rheumatoid↗
PubMed1983

Serial circulating immune complexes and mononuclear phagocyte system function in infective endocarditis.

Twenty patients with infective endocarditis were followed prospectively and all had elevated levels of circulating immune complexes (CICs) detected by staphylococcal binding assay. Mean CIC levels declined for the group as a whole (193 micrograms/ml +/- 24 to 100 +/- 17, p less than 0.05) and became undetectable in eight patients (47%) who were cured. Patients who died or had complicated courses had higher mean CIC levels at the start and finish (254 micrograms/ml +/- 24 and 145 +/- 37) of antibiotic therapy than patients with uncomplicated courses (178 micrograms/ml +/- 19 and 38 +/- 24), p less than 0.05. CIC levels did not decline significantly in patients with glomerulonephritis or arthritis, in contrast to patients without these features. Despite elevated CIC levels, 10 patients had enhanced mononuclear phagocyte system (MPS) function as assessed by Fc-dependent IgG-coated red blood cell clearance. These data suggest that CICs probably are pathogenic in endocarditis and may contribute to the development of arthritis and glomerulonephritis. Elevated CICs in infective endocarditis do not appear to be directly related to defective MPS function.

Adult↗
PubMed1982

Variable response to oral angiotensin-converting-enzyme blockade in hypertensive scleroderma patients.

Twelve scleroderma patients with hypertension, seven of whom had malignant hypertension and renal failure of scleroderma renal crisis, were treated with captopril. The first dose lowered mean pressure in all patients by 21.3 mmHg; in 6 patients it relieved encephalopathy. Blood pressure was controlled in all patients. Two of 7 patients with scleroderma renal crisis had improvement in renal function; the 5 patients who did not have malignant hypertension improved or stabilized. Despite good pressure control, however, renal failure developed in 5 patients with scleroderma renal crisis. The data indicated that captopril is effective antihypertensive therapy in scleroderma and, when given early, may prevent renal failure and death.

Administration, Oral↗
PubMed1982

Identification of bacterial antigens in circulating immune complexes of infective endocarditis.

The presence of circulating immune complexes (IC) in patients with infective endocarditis has been well documented but the contributions of host and bacterial components to these IC have not been defined. To study this question, IC were isolated from serum of a patient with Streptococcus faecalis endocarditis by differential polyethylene glycol precipitation and competitive binding to staphylococcal protein A. A rabbit antiserum raised against the purified IC had reactivity by crossed immunoelectrophoresis primarily with an antigen derived from the cytoplasm of the infective organism. The antigen was a protein with a 12,000-dalton molecular mass. In situ radiolabeling of the IC bound to the protein A demonstrated a component of the same molecular mass as the bacterial antigen recognized by the antiserum. The patient serum had multiple antibody specificities reactive with bacterial antigens, including the antigen recognized by the rabbit anti-IC antiserum. These techniques for isolation and characterization of circulating IC may have value in the study of IC diseases in which the inciting antigens are not known.

Animals↗
PubMed1982

Defective Fc receptor-mediated function of the mononuclear phagocyte system in lupus nephritis.

To determine whether patients with systemic lupus erythematosus and nephritis have more profound defects in mononuclear phagocyte system clearance than their counterparts without renal disease, we studed Fc receptor-mediated splenic clearance function in 32 patients. Clearance half-times were prolonged in patients with lupus erythematosus compared with those in normal controls (p less than 0.0001) and longer in patients with renal disease than in those without (p less than 0.025). Both renal (tau = 0.45, p less than 0.0002) and nonrenal (tau = 0.35, p less than 0.003) disease activity were significantly but independently associated with clearance half-times. When matched for nonrenal activity, patients with nephritis had greater clearance dysfunction than their counterparts without renal disease. Circulating immune complexes did not correlate with clearance for all patients. Neither B8 nor DR3 histocompatibility antigen markers differentiated the renal and nonrenal disease subgroups. The greater Fc receptor-mediated clearance dysfunction, which occurs in patients with lupus erythematosus and nephritis, could lead to enhanced glomerular deposition of immune complexes as a primary event, or as a secondary event amplifying previously established lesions.

Adult↗
PubMed1981

High-dose intravenous methylprednisolone pulse therapy in systemic lupus erythematosus.

To determine guidelines for treatment with high-dose intravenous methylprednisolone in lupus nephritis, we prospectively assessed the response to pulse therapy in 34 patients. In 12 of them, serum creatinine decreased by at least 20 percent within two months of treatment whereas in the remaining 22 there was no such response. Patients who responded were characterized by recent deterioration in function whereas nonresponders had had a more stable antecedent course (p = 0.003). Responders also had more diffuse lesions on renal biopsy (p = 0.028), had higher levels of anti-DNA antibodies (p less than 0.05), and tended to have higher titers of immune complexes and lower total hemolytic complement. High-dose intravenous methylprednisolone therapy may lead to striking improvement in renal function in lupus nephritis, especially in the subset of patients with recent antecedent functional deterioration. This improvement was maintained in 60 percent of the patients who responded for at least six months.

Adolescent↗
PubMed1980

Arthralgia associated with acute urinary retention. A syndrome of probable viral etiology.

Four patients are described in whom paresthesia and arthralgia developed in association with acute urinary retention. Neurologic and musculoskeletal complaints persisted for varying periods, up to five year, after cessation of urinary symptoms. Significantly elevated titers to Herpes simplex and Herpes zoster viruses were observed in three and four subjects, respectively, although none exhibited cutaneous lesions of herpetic infection. The symptom complex, presumably the result of viral radiculitis, may present in varying patterns that can be confused with lumbar disc protrusion, obstructive uropathy or primary rheumatic disorder. Diagnostic studies requisite for documentation of a viral etiology of the syndrome are discussed.

Adult↗
PubMed1980

Bilateral necrotising scleritis with marginal corneal ulceration after cataract surgery in a patient with vasculitis.

The onset of bilateral necrotising scleritis and marginal corneal ulceration after cataract surgery are described in a patient with diffuse vasculitis syndrome. The finding of immune complexes in this patient's tissue biopsy suggests that they are the cause of a localised primary vasculitis triggered by surgical inflammation. Clinically, this patient's marginal corneal ulceration preceded the scleral necrosis. A past history of orbital inflammation may have been due to a posterior scleritis. The corneal ulcerations responded to conjunctival debridement and steroids. The scleral necrosis was unresponsive to the 2 anti-inflammatory preparations tried, and the patient eventually went into remission while off all treatment.

Aged↗
PubMed1979

Binding of immunoglobulin G aggregates and immune complexes in human sera to Staphylococci containing protein A.

Using the Cowan I strain of Staphylococcus aureus, we compared the binding properties of human monomeric immunoglobulin (Ig)G and oligomeric or complexed IgG. Heat-aggregated IgG served as a model for complexed IgG and heat-killed, formalin-fixed S. aureus (StaphA) as a cellular receptor for IgG, in determining the parameters for oligomeric and monomeric binding. Because of its capacity for multipoint attachment, complexed IgG binding was favored over monomeric IgG binding, and this preferential binding was demonstrated kinetically in equivalent forward rates of binding but in a much slower rate of release from StaphA receptors. From binding studies, we determined which conditions maximize complexes IgG binding and minimized monomeric IgG binding and applied them to the development of an assay for aggregated IgG and immune complexes in human sera. The StaphA binding assay that was devised is quantitative, sensitive, and not complement dependent. It is relatively unaffected by factors such as heparin, complement fixation, native antibodies, and immunoglobulin concentrations, but is affected by the presence of rheumatoid factors. It compares favorably with two other complement-dependent assays of immune complexes, the 125I-Clq binding assay and the Raji cell assay, in terms of sensitivity and the size of immune complexes detected. Studies on the potential of the assay for detecting, isolating, and characterizing immune complexes in biological fluids are presented.

Antigen-Antibody Complex↗
PubMed1979

Rheumatoid meningitis: a localized immune process.

Rheumatoid pachymeningitis is a rare complication of rheumatoid arthritis. This disease was confined to the dura and pia-arachnoid of the lumbar cord in our patient. Her neurologic deficits responded to surgical decompression and corticosteroid therapy. Radiologic evidence and the differences in cell count, protein, and glucose content between lumbar and cisternal cerebrospinal fluid indicate that rheumatoid pachymeningitis can be localized to a discrete region of the central nervous system. Elevated immunoglobulins, IgM and IgG rheumatoid factors, low molecular weight IgM, and immune complexes were found in the cerebrospinal fluid and implicate an immune reaction in the pathogenesis of this disease, which is probably similar to inflammatory processes involving other organs in rheumatoid arthritis.

Aged↗
PubMed1978

Fibrinogen turnover in progressive systemic sclerosis.

Large amounts of fibrin are seen in the intima of the renal arterioles in progressive systemic sclerosis (scleroderma). The half-life or half disappearance time of plasma fibrinogen in 15 patients with scleroderma was studied using 125I fibrinogen to find whether there is an increased turnover of plasma fibrinogen paralleling this morphologic abnormality. Patients had a more rapid fibrinogen turnover than normal controls (60.7 versus 90.6 hours); the subgroup of patients with "progressive" scleroderma had a more rapid fibrinogen half-life than those with "stable" scleroderma (56.5 versus 73.2 hours). The mean fibrinogen half-life of 8 patients given intravenous heparin increased to within one standard deviation of normal, a finding that suggested that the fibrinogen molecule in these patients was capable of normal survival. There was a considerable variation of normal survival. There was a considerable variation of fibrinogen half-lives in individual scleroderma patients over time (not seen in the normal controls) which may be the result of intermittently increased fibrinogen consumption.

Adult↗