Search PubMed⌕ Search

Biomedical subjects

J B Peter

Publications and source records attributed to J B Peter.

At least 127 records · Page 7Linked to original sources
PubMed1988

Studies of IgG, IgM and IgA antiphospholipid antibody isotypes in systemic lupus erythematosus.

We evaluated the clinical relevance of 6 antiphospholipid antibodies including cardiolipin and their IgG, IgM and IgA isotypes in 92 patients with systemic lupus erythematosus (SLE). Antiphospholipid antibodies generally had significant associations with thrombocytopenia and a history of false-positive syphilis serologies. In 4 of 6 antiphospholipid antibodies, an inverse association with renal disease was observed. Antiphospholipid antibodies may moderate or protect against renal disease, or this may reflect the high doses of corticosteroids and cytotoxic drugs received by this group. Further studies are needed to determine how many antibody families cause these activities and to elucidate whether certain SLE subgroups possess differing specificities for each of the phospholipids.

Adolescent↗
PubMed1987

Influence of specimen treatment on nonreactive HTLV-III sera.

We investigated effects of specimen treatment on HTLV-III antibody assay results. Freezing and thawing specimens 10 times did not increase specimen mean absorbance (A) values measured by the Abbott immunoenzymometric assay (IEMA). Heating blood donor serum specimens at 56 degrees C for at least 10 min inactivates virus, but converted 7.1% of nonreactive specimens to positive when measured by this IEMA. Also heating at 56 degrees C for 30 min increased A values of most specimens; however, the conversion to positive within assay ranged from 0 to 75%, with a mean of 17%. When 56 nonreactive patient specimens were heated, 55% became Abbott IEMA reactive, although ENI IEMA values did not increase and Western blot results remained nonreactive. Binding of immunoglobulins G and A to Abbott IEMA beads did not cause this conversion after heat treatment. We postulate that heating specimens causes alteration of some serum matrices and introduces nonspecific binding to assay bead antigen or antibody reagents. We recommend that for the Abbott IEMA, specimens may be stored frozen, and must not be heated to avoid altered reactivity.

Antibodies, Viral↗
PubMed1987

Presence of HTLV-III antibodies in immune serum globulin preparations.

The authors tested 15 immune serum globulin pharmaceutical preparations for antibody reactivity to human T cell lymphotrophic virus type III (HTLV-III) by the Abbott immunoenzymometric assay (IEMA). Although no evidence of HTLV-III infectivity has appeared after injection of similar preparations into humans, the authors found all samples IEMA reactive. Upon dilution, the authors demonstrated parallel decreases of antibody reactivity among two samples of gamma globulin, the Abbott-positive control, and a markedly reactive patient specimen. Gamma globulin isolated from sera of six animal species was nonreactive in the Abbott assay. All samples were nonreactive with the H-9 cell line antigen. Antibody reactivity to HTLV-III was confirmed in 13 of 15 gamma globulin samples when tested by the Electro-Nucleonics IEMA, and 14 samples contained at least the p24 band on Western blot analysis. Although false positivity occurs in IEMA assays possibly because of elevated protein concentrations and nonspecific binding, the authors, results show that in most circumstances immune serum globulin preparations tested do contain true reactivity to HTLV-III.

Antibodies, Viral↗
PubMed1987

Simplification and standardization of dot-ELISA for human schistosomiasis mansoni.

Dot-ELISA, a technique that shares the same principles as the enzyme immunoassay, is useful for detection of anti-Schistosoma mansoni antibodies in the sera of patients with Schistosoma mansoni infections. The antigens were fixed to the nitrocellulose strips, blocked with 1% bovine serum albumin in 0.05% Tween 20. Patient sera (40) and normal laboratory personnel sera (9) were applied to the sheet directly, without cutting the strips into small discs. The nitrocellulose sheets are kept in a humid chamber for 30 min and then washed. After incubation with peroxidase-conjugated goat anti-human antibody, washing, and addition of substrate, positive reactions appear as brown dots against the white background. The room temperature assay takes about 2 hr. The optimum antigen concentration is 20-80 ng per dot and the optimum serum dilution is 1:100-1:400. The sensitivity and specificity of the assay are 90-95% and 90%, respectively. The level of positivity of the dot-ELISA by an arbitrary scale compares with standard micro-ELISA. The single positive reaction in a normal serum sample in dot-ELISA is also positive in micro-ELISA. Cross-reactivity between the S. mansoni antigen and human fascioliasis sera was noticed in 2 out of 8 patient sera. Good correlation between the arbitrary level of dot-ELISA and the absorbance of standardized micro-ELISA shows that the dot-ELISA is useful both for laboratory and field studies.

Antibodies↗
PubMed1987

Penicillamine induced polymyositis and dermatomyositis.

Eight Australian cases of D-penicillamine induced polymyositis/dermatomyositis (PM/DM) are reported. In terms of clinical, pathological and electromyographic features, D-penicillamine PM/DM is similar to idiopathic PM/DM but is generally less severe. Recovery is usually rapid when D-penicillamine is withdrawn. Sera were available for study in 6 of the 8 reported cases. Two of the 6 had elevated titers of acetylcholine receptor autoantibodies. Neither of these patients had clinical signs of myasthenia gravis. In 3 of 6 patients typed for C2, no bands were detected suggesting homozygous C2 deficiency. D-penicillamine PM/DM is associated with HLA-B18, B35 and DR4 and is immunogenetically different from idiopathic PM/DM, rheumatoid arthritis and D-penicillamine myasthenia gravis.

Adult↗
PubMed1986

Efficacy of doxepin in the treatment of chronic idiopathic urticaria.

Doxepin hydrochloride, a tricyclic antidepressant, was evaluated in a double-blind, placebo-controlled crossover trial for the treatment of chronic idiopathic urticaria in 16 adults. Efficacy was evaluated by symptom scores, concomitant antihistamine use, and suppression of histamine- and codeine-induced wheal response. Doxepin-treated subjects experienced fewer lesions (p less than 0.001), less waking hours with lesions (p less than 0.01), lesser degree of itch and/or discomfort (p less than 0.001), and less swelling or angioedema (p less than 0.001) as compared to placebo-treated subjects. Doxepin-treated subjects required less daily concomitant antihistamine use (mean 0.13 tablets versus 1.48 tablets, p less than 0.05). Doxepin also significantly suppressed histamine- and codeine-induced cutaneous wheal response as compared to placebo. Lethargy was commonly observed but diminished with continued use. Dry mouth and constipation were also commonly observed. We conclude that doxepin is an effective agent for the treatment of chronic idiopathic urticaria.

Chlorpheniramine↗
PubMed1984

A creative combination: why commercial and hospital laboratories should unite.

The trend for existing hospital laboratories to combine with their commercial counterparts is a prudent one, the author says. He recommends that hospitals continue to perform routine testing, but send the sophisticated, high-technology tests to a commercial laboratory. His advice: Several hospitals should join to own and operate the central facility in combination with a reference laboratory. He concludes with practical suggestions, guided by experience, to make this model work.

Commerce↗
PubMed1984

A cytotoxic monoclonal antibody detecting a novel B cell membrane antigen expressed predominantly on cells bearing surface membrane immunoglobulin.

A new human B lymphocyte membrane antigen, CB2, has been detected by a mouse monoclonal IgM antibody. CB2 appears to be predominantly expressed on normal and malignant cells expressing surface membrane immunoglobulin (SmIg). By indirect immunofluorescence, the number of CB2-positive cells in normal peripheral blood correlated well with the number of SmIg-positive cells. Cytotoxicity studies on isolated cell populations showed that CB2 was present on normal B cells isolated from the spleens of 52 donors and on peripheral blood B cells from 8 donors. Monocytes, T cells, granulocytes, platelets, and red cells were CB2 negative. Only malignant cells expressing SmIg were positive. These included B-CLL, B lymphoma, prolymphocytic leukemia, and B lymphoma cell lines Daudi, Raji, and Conception. SmIg-negative leukemia cells, such as common acute lymphoblastic leukemia, acute and chronic myelogenous leukemia, and T cell leukemias, were negative. Blocking studies with human immunoglobulin suggests that the CB2 antigen is not directed against immunoglobulin determinants. Immunoperoxidase studies on normal lymph node sections show that CB2-positive cells are predominantly present in the mantle region of the follicle, whereas B1-positive cells are mainly in the germinal center.

Animals↗
PubMed1980

Detection of thymoma in myasthenia gravis.

Twenty patients with myasthenia gravis had chest radiography, conventional tomography, and computed tomography (CT) of the thorax within 1 month of thymectomy. Four of the six macroscopic tumors were detected on routine chest radiography; conventional tomography provided no additional information. CT detected all six macroscopic tumors and provided additional information that was not available by other procedures. However, 18 patients (90%) had anterior mediastinum densities on CT, which could not be distinguished preoperatively from thymic tumors. All six patients with macroscopic tumors had serum antistriational muscle antibody titers; this test was negative in 10 of 11 patients (91%) without thymoma. Chest radiography, CT of the thorax, and antistriational antibodies are the tests recommended for detection of a thymoma in patients with myasthenia gravis.

Acetylcholine↗
PubMed1980

Ritodrine hydrochloride: a betamimetic agent for use in preterm labor. I. pharmacology, clinical history, administration, side effects, and safety.

Ritodrine hydrochloride has become the first drug approved in the United States specifically for use in preterm labor. The drug is a beta-sympathomimetic agent with predominant effects upon beta 2 receptors of the uterus. In this report, the pharmacology, distribution, disposition, and excretion are briefly reviewed. Recommendations for selecting patients most likely to benefit from ritodrine are given, together with the dosage and administration schedules that have been found most effective. Although this drug is not without side effects, it has been more thoroughly evaluated in prospective double-blind controlled trials than any of the other agents commonly used in preterm labor. In comparison with these agents, it seems relatively safe and the side effects are usually well tolerated. Part 2 of the paper discusses the evidence for efficacy.

Administration, Oral↗
PubMed1980

Ritodrine hydrochloride: a betamimetic agent for use in preterm labor. II. Evidence of efficacy.

In a multicenter series of randomized prospective double-blind controlled studies, ritodrine hydrochloride was compared with either ethanol or placebo in treatment of idiopathic preterm labor. When compared with controls, there was, among offspring of ritodrine-treated mothers, a significantly reduced incidence of neonatal death and respiratory distress syndrome (P less than .05 in both comparisons) and a significantly higher proportion of infants achieving 36 weeks' gestation (P less than .05) or birth weight greater than 2500 g (P less than .05). There was also a significant improvement in gestational age at delivery (P less than .05) and in the number of days gained in utero (P less than .001) among ritodrine-treated patients as compared with controls. These results, coupled with a finding of generally acceptable side effects, have contributed to ritodrine's becoming the first drug approved for the treatment of preterm labor in the United States.

Birth Weight↗