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Biomedical subjects

J D Folds

Publications and source records attributed to J D Folds.

At least 37 records · Page 2Linked to original sources
PubMed1993

Comparison of seven commercial kits for detection of antibodies to Borrelia burgdorferi.

Five enzyme immunoassay (EIA) and two Western blot (WB) commercial kits were compared for their ability to detect antibodies to Borrelia burgdorferi. The panel of 53 test sera consisted of 25 sera positive for antibodies to Borrelia burgdorferi, 15 sera negative for such antibodies, 5 sera reactive in serologic tests for syphilis, and 8 sera containing antinuclear antibodies and/or rheumatoid factor. The rate of agreement with reference results was 93%, 90%, 90% and 88% for EIA kits from Diamedix, Cambridge Biotech, Mardx and Sigma respectively. The sensitivity and specificity was 84% and 100% respectively for Cambridge Biotech, 76% and 94% for Diamedix, 68% and 83% for Mardx, and 68% and 83% for Sigma. The three confirmatory tests, Cambridge Biotech WB, General Biometrics P39 EIA and Mardx WB, demonstrated 75%, 60% and 63% agreement respectively. The sensitivity and specificity was 52% and 100% respectively for Cambridge Biotech WB, 24% and 100% for General Biometrics P39 EIA, and 44% and 100% for Mardx WB. The results demonstrate the variable performance of commercial serologic kits for detection of antibodies to Borrelia burgdorferi. WB appears to be a better confirmatory test than the single protein EIA.

Antibodies, Bacterial↗
PubMed1993

Infectious immune complexes in HIV-1-infected patients.

Using polyethylene glycol (PEG) precipitation we have found that most HIV-1 seropositive patients have IgG containing-circulating immune complexes (CIC). In addition these CIC sometimes contain IgA, IgM, C3, and/or HIV p24 antigen. Previous work has demonstrated that patients who have plasma viremia, CD4 cell counts less than 170/mm3, or who are symptomatic are more apt to have HIV that is precipitable with PEG. In this study we report that the infectious HIV found in the plasma of patients with plasma viremia could only be found in the 2% PEG precipitates, i.e., PEG supernatants never contained infectious HIV, although they often contained noninfectious p24 antigen. These results suggested that at least some of the infectious HIV circulating in the plasma of infected patients is in the form of immune complexes. To support this idea we also demonstrated that infectious HIV could be precipitated with antiserum raised to either immunogloblins or complement components.

Antigen-Antibody Complex↗
PubMed1993

Evaluation of the Rheuma-Lex latex agglutination test for detection of rheumatoid factor.

The performance of the Trinity Laboratories Rheuma-Lex latex agglutination test kit for detection of Rheumatoid factor (RF) in patient sera was evaluated. The method and test results of the Rheuma-Lex test were compared to those obtained with another commercially available latex agglutination test kit (RapiTex RF Test) on 162 sera submitted for RF testing. Discrepant results were resolved by testing those sera with a third commercially available kit. The Rheuma-Lex and the RapiTex kits demonstrated sensitivities of 100 and 87%, specificities of 98 and 99%, negative predictive values of 100 and 97%, positive predictive values of 94 and 94% and efficiencies of 99 and 97% respectively. The Rheuma-Lex test kit was judged to be a sensitive, reliable and simple assay for RF detection in serum.

Humans↗
PubMed1992

Circulating natural killer cell phenotypes in men and women with major depression. Relation to cytotoxic activity and severity of depression.

The effects of major depression on peripheral blood natural killer cell phenotypes and natural killer cell activity were studied by comparing depressed and normal control subjects. Depressed subjects exhibited (1) significant reductions in Leu-11 (CD16) natural killer effector cells and natural killer cell activity and (2) a dissociation of the normal positive correlation between the percentage of Leu-11 cells and natural killer cell activity. These findings suggest that alterations in the availability and the killing capacity of circulating Leu-11 natural killer cells appear to be responsible for depression-related reductions in natural killer cell activity. Moreover, men with major depression showed marked reductions in Leu-11 cells, natural killer cell activity, and Leu-7 (HNK-1) lymphocytes compared with normal control men. By contrast, depressed women did not differ significantly from normal control women on any of these three immune function measures. Severity of depression as assessed by Hamilton Rating Scale for Depression scores was not associated with natural killer cell activity or Leu-7 lymphocyte levels in either men or women with major depression. Hamilton Rating Scale for Depression severity ratings were, however, strongly inversely correlated with Leu-11 lymphocyte counts among men, but not women, with major depression. These data begin to elucidate the immunological mechanisms by which natural killer cell activity is altered in depression and suggest that some measures of immunity may be differentially affected in male and female subjects with the syndrome of major depression.

Adolescent↗
PubMed1992

Abnormal diurnal variation in circulating natural killer cell phenotypes and cytotoxic activity in major depression.

This investigation tested the hypothesis that depressed patients have abnormal diurnal variation of natural killer (NK) cell measures. The diurnal variation of levels of Leu-11 NK cells and NK cytotoxic activity was significantly less in 24 patients with major depression than in 24 normal comparison subjects. These findings provide evidence that aspects of immune, as well as neural and endocrine, chronobiology are abnormal in depression.

Adult↗
PubMed1991

Detection of infectious immune complexes in human immunodeficiency virus type 1 (HIV-1) infections: correlation with plasma viremia and CD4 cell counts.

The detection of infectious immune complexes in plasma after human immunodeficiency virus (HIV) infection may be useful as a surrogate marker of progression of disease and may help in understanding the pathogenesis of AIDS. Polyethylene glycol (PEG) precipitates of plasma were tested for the presence of HIV p24 antigen and infectious virus. Results were compared with data from cell and plasma cultures, plasma p24 antigen, CD4 cell counts, and stage of disease. PEG precipitation increased the detection rate of the p24 antigen assay from 38.3% to 58.7%. There was a significant correlation between precipitable p24 antigen and plasma viremia, changes in CD4 cell counts, and progression of disease. The sensitivity of the PEG-precipitable p24 antigen assay versus traditional p24 antigen testing was 59.0% and the specificity 91.7%. The assay was reproducible and may be a useful determinant of viral load, clinical progression, and antiretroviral efficacy.

AIDS-Related Complex↗
PubMed1991

Interpretive criteria of the Western blot assay for serodiagnosis of human immunodeficiency virus type 1 infection.

This project was designed to evaluate different criteria used in the interpretation of the human immunodeficiency virus type 1 (HIV-1) Western blot assay on a group of serum samples blinded to the examiner that were collected from individuals attending three different public health departments in central North Carolina. Each individual also completed an anonymous linked questionnaire regarding sociodemographics and risk factors for blood-borne infections. All of the Western blot assays for human immunodeficiency virus type 1 were interpreted according to the criteria established at the University of North Carolina Hospitals, Chapel Hill, the Centers for Disease Control, Atlanta, Ga, in association with the Association of State, Territorial, and Public Health Laboratory Directors, Iowa City, Iowa, the American Red Cross, Washington, DC, the Consortium for Retrovirus Serology Standardization, Davis, Calif, and the Food and Drug Administration, Washington, DC. The results obtained were grouped as positive, negative, and indeterminate according to each organization's criteria and analyzed in the context of the associated risk factors. The results indicate that institutions performing human immunodeficiency virus type 1 Western blot confirmatory testing should adopt the criteria of the Centers for Disease Control and the State, Territorial, and Public Health Laboratory Directors.

AIDS Serodiagnosis↗
PubMed1989

Antibody specificity for human immunodeficiency virus type 1 in serum and cerebrospinal fluid from patients with AIDS and AIDS-related complex.

Since little information has been reported about the specificity of antibodies to human immunodeficiency virus type 1 (HIV-1) found in the cerebrospinal fluid (CSF), 21 CSF and serum specimens were examined from 19 patients with clinical AIDS, AIDS-related complex, or asymptomatic HIV-1 infection. The predominant specificity of antibodies using Western blot analysis in both serum (100%) and CSF (100%) was directed toward env gene products. The next most common antibody specificities were to the pol gene products (serum 95%; CSF 62%). Less commonly found was antibody to the gag-encoded proteins (serum 71%; CSF 38%). The level of antibody to HIV-1 in CSF could not be predicted from the level found in serum. Also, the spectrum of antibodies seen did not correlate with disease stage or with the quantity of antibody present. The serum/CSF pairs were also examined for the presence of HIV-1 antigen by commercial enzyme immunoassay. HIV-1 antigen was present in eight of 19 (43%) of the serum samples and five of 20 (25%) of the CSF samples tested.

AIDS-Related Complex↗
PubMed1989

Dexamethasone effects on numbers of cells in lymphocyte subpopulations: changes associated with major depression and DST nonsuppression.

1. The authors studied the effects of administration of 1 mg of dexamethasone on the number of cells in discrete subpopulations of lymphocytes in major depressed and psychiatric control patients with depressive symptoms. 2. Dexamethasone significantly decreased the total lymphocyte count and numbers of T and helper T lymphocytes in control patients. 3. In contrast, dexamethasone failed to significantly decrease the numbers of cells in any of the subpopulations of lymphocytes studied in major depressed patients. 4. Among major depressed patients both DST suppressors and nonsuppressors were insensitive to the suppressive effects of dexamethasone on lymphocyte numbers. 5. However, in DST nonsuppressors, but not in DST suppressors, dexamethasone administration significantly increased the number of cytotoxic/suppressor T lymphocytes and natural killer cells. 6. The authors conclude that insensitivity to the suppressive effects of dexamethasone on lymphocyte numbers is specific to major depression and is not associated with DST status. However, DST nonsuppression is associated with a facilitating effect of dexamethasone on the number of cells in some subpopulations of lymphocytes.

Adolescent↗
PubMed1988

Immediate effects of intravenous IgG administration on peripheral blood B and T cells and polymorphonuclear cells in patients with myasthenia gravis.

Five patients with myasthenia gravis, who received treatment with intravenous 7S gamma-globulin were monitored for changes in immunological status. Serum immunoglobulin G increased from an average of 1.4 to 4.7 g/dl during the 5-day course of therapy. Specific antibody to the acetylcholine receptor present in three of five patients did not change. A transient decrease in total peripheral blood leukocytes was observed in five patients due to decreases in the absolute number of polymorphonuclear cells and lymphocytes in the circulation. Lymphocyte surface marker studies revealed that the percentage of surface immunoglobulin positive cells increased in all patients from an average of 13 to 26% by day 5 of therapy; however, the percentage of HLA-Dr- and Leu 12 (CD19)-positive B cells did not change. Lymphoid cells positive for the Leu 11 (CD16) marker doubled from an average of 11 to 24% during the 5-day course of therapy. Surface Ig-positive cells and Leu 11 (CD16)-positive cells returned to pretreatment values by 7 days posttherapy. Helper/suppressor cell ratios slowly decreased in all patients from an average of 2.9 to 2.2 by 1 week posttherapy and remained low for several weeks.

B-Lymphocytes↗
PubMed1988

Major depression and immunity: preliminary evidence of decreased natural killer cell populations.

1. Alterations in cellular immunity have been suggested to occur in major depressed patients. 2. To investigate the populations of B-cells, T-cells and T-cell subsets in major depression, the authors utilized monoclonal antibody techniques to enumerate the number of total lymphocytes, B-cells and T-cell subpopulations in recently admitted patients with major depression or non-affective disorders. 3. The authors also studied the relationship between the immune state and hypercortisolism as measured by post-dexamethasone serum cortisol. 4. The preliminary findings from this pilot study suggest that major depressed patients may have altered cellular immunity as demonstrated by lower numbers of natural killer cells. 5. Further study will be necessary to confirm the trend for lower numbers of T-cell lymphocytes and T-cell subpopulations including helper cells, suppressor cells and natural killer cells in patients with non-suppression of serum cortisol following dexamethasone.

B-Lymphocytes↗
PubMed1987

Evaluation of latex-based heterophile antibody assay for diagnosis of acute infectious mononucleosis.

The diagnosis of an acute episode of infectious mononucleosis (IM) is made on the basis of clinical symptoms and serological evidence for development of heterophile antibodies. In an effort to obtain a very sensitive and specific assay for diagnosis of IM, we have developed MERISTAR:IM. The MERISTAR assay uses latex beads coated with purified bovine heterophile antigen. We compared the sensitivity and specificity and performance characteristics of the latex-based test to those of the commercially available erythrocyte-based Monospot test with serum samples from 363 suspected-IM patients and controls. A total of 28 samples from patients with confirmed IM were positive with the MERISTAR assay, while only 23 of the samples were positive with the Monospot assay. The two assays had equal specificity, as each test gave two false-positive results. In the technical performance of the assay, the MERISTAR assay was simpler and faster to perform than the Monospot assay.

Acute Disease↗
PubMed1986

Immunoblot analysis of antigens associated with Haemophilus ducreyi using serum from immunised rabbits.

Sodium dodecyl sulphate polyacrylamide gel electrophoresis and immunoblotting were used to characterise isolates of Haemophilus ducreyi. Isolates of H ducreyi were heterogeneous in protein composition, but isolates from single outbreaks appeared similar both in protein profiles and antigenic analysis. Rabbits immunised with H ducreyi responded with a vigorous humoral immune response in which multiple antigenic polypeptides were detected. The most prominent antigens had molecular masses of 67, 42, 22.5, and 20 kilodaltons.

Animals↗
PubMed1985

Humoral response of the mouse to Treponema pallidum.

To investigate the development of the humoral immune response of mice to infection with Treponema pallidum, Balb/c and C57Bl mice were injected intradermally with 10 x 10(6) virulent organisms. Serum samples were taken from the mice at weekly intervals after infection and used in the electrophoretic transblotting technique to detect T pallidum and T phagedenis biotype Reiter antigens. The serum samples taken from infected mice at 21, 42, 84, and 126 days after infection recognised two to 15 T pallidum antigens, with a gradual but continual increase in the number of antigens recognised. The same antisera to T pallidum recognised five cross reactive T phagedenis biotype Reiter antigens. Mice injected with 10 x 10(6) heat killed T pallidum organisms failed to recognise T pallidum antigens, as shown by the blotting technique. When mice infected with T pallidum were given antibiotics, the development of the humoral response was interrupted. These experiments indicated that mice respond more slowly than rabbits to T pallidum, which may be because T pallidum is weakly immunogenic in mice.

Animals↗
PubMed1984

Nonurban male homosexuals: epidemiologic, immunologic and virologic characteristics.

Twenty asymptomatic male homosexuals living in North Carolina were evaluated looking at epidemiologic, immunologic and virologic characteristics. In ten subjects selected for inhalant nitrite use a significantly higher frequency of multiple drug abuse and a trend toward greater sexual promiscuity was found in comparison with ten nonnitrite users. None of the 20 subjects had chronic lymphadenopathy. Cytomegalovirus (CMV) was not found in urine, blood or throat washings, but was found in 29% of the subjects' semen specimens--a finding that was significantly linked (P less than .05) to the presence of CMV IgM antibody in serum. There were no abnormal helper lymphocytes: suppressor T lymphocyte ratios (all greater than 1.3) and lymphocyte mitogen stimulations were not different from heterosexual controls in contrast to frequent abnormalities reported in male homosexuals in metropolitan areas. If these immunologic findings are reproducible, they may be important in understanding why the Acquired Immunodeficiency Syndrome has clustered in large cities.

Adult↗
PubMed1983

Evaluation of the inbred mouse as a model for experimental Treponema pallidum infection.

Mice of several inbred strains were studied for responses to Treponema pallidum (Nichols). Mice were injected with viable treponemes and observed daily for the presence of lesions or signs of illness. Although none of the mice developed detectable lesions, they did develop specific anti-T. pallidum antibodies that were observed as early as 21 days after inoculation with viable T. pallidum. The antibodies were detected by an enzyme-linked immunosorbent assay and by passive haemagglutination.

Animals↗
PubMed1983

Development of monoclonal antibodies that recognize Treponema pallidum.

We developed a panel of monoclonal antibodies to Treponema pallidum (Nichols) antigens, some of which recognize treponemal antigens on T. pallidum (Nichols), T. pallidum strain 14, and Treponema phagedenis biotype Reiter. The antibodies were detected by either an enzyme-linked immunosorbent assay or a radioimmunoassay.

Animals↗