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Biomedical subjects

D L Madden

Publications and source records attributed to D L Madden.

At least 37 records · Page 2Linked to original sources
PubMed1987

Difficulties associated with serological diagnosis of Toxoplasma gondii infections.

Physicians often rely on serology to help determine whether a patient has had a recent infection with Toxoplasma gondii and as an aid in estimating the possible teratogenic effect on the fetus. For this reason the diagnostic laboratory should take every precaution to avoid misleading results. The best serological analysis is based on a rise in IgG titer with two appropriately spaced serum samples. Also, the presence of a high IgM titer in one serum sample is generally considered to be good evidence that infection has occurred recently. The indirect fluorescent antibody (IFA) test has been the most widely used test for detection of IgG or IgM. Recently enzyme-linked immunosorbent assays (ELISA) have also been developed for this purpose. In this study we reaffirm that false IgM positive results can occur with these tests because of the presence of rheumatoid factor in serum, and false negative results can also occur because of competitive inhibition by specific IgG. We show that a preabsorption of serum with a Staphylococcus/Streptococcus preparation (Staffinoc, MA Bioproducts, Walkersville, MD) removes IgG and IgA and eliminates many of the false reactions. We have also found that elevated levels of specific IgM can persist for at least several years in some women. This suggests that the presence of IgM alone is not always an indication of recent infection.

Enzyme-Linked Immunosorbent Assay↗
PubMed1986

Administration of recombinant human leukocyte alpha 2-interferon in patients with amyotrophic lateral sclerosis.

Recombinant leukocyte alpha 2-interferon (with greater than 98% purity) was evaluated in a pilot treatment in six patients with amyotrophic lateral sclerosis and one patient with slowly progressive postpoliomyelitis motor neuron disease. Interferon, administered subcutaneously in doses of 2 million units three times per week for four months, was ineffective in improving, arresting, or slowing the pace of progression in all the patients who were followed up for ten to 14 months after the end of therapy.

Adult↗
PubMed1986

Cross-sectional seroepidemiologic study of the prevalence of cytomegalovirus and herpes simplex virus infection in a Canadian Inuit (Eskimo) community.

The prevalence of antibody to cytomegalovirus (CMV) and herpes simplex virus (HSV) was determined, using enzyme-linked immunosorbent assay techniques, in a cross-sectional serologic survey of an isolated northern Canadian Inuit (Eskimo) community. The population studied included 155 Inuit and 11 Caucasian residents. By 6 years of age, 80% of the Inuit population were seropositive for CMV and 100% for herpes simplex virus. While only 7/63 Inuit greater than 20 years were seronegative for CMV, 5/11 Caucasian residents were seronegative (p = 0.01). For the Inuit population, no association between seropositivity for CMV and seropositivity for hepatitis A or hepatitis B was observed. This prevalence survey shows a serologic profile for infection with CMV and HSV in this northern Inuit community with an early age of acquisition and high prevalence of infection characteristic of socioeconomically deprived populations throughout the world, and is distinct from that observed in many other North American populations.

Adolescent↗
PubMed1985

Immune defects in simian acquired immunodeficiency syndrome.

We recently reported a Simian Acquired Immunodeficiency Syndrome (SAIDS) in rhesus macaques at the California Primate Research Center. Here, we studied in vitro lymphocyte response to the mitogens Concanavalin A (Con A), phytohemagglutinin (PHA) and pokeweed mitogen (PWM) with and without interleukin 2 (IL-2). Immunoglobulin (IgG and IgM) and complement (C3 and C4) concentrations were determined by radial immunodiffusion. T helper and T suppressor lymphocytes were identified with the monoclonal antibodies OKT4 and OKT8. Concentrations of IgG and IgM were significantly (p less than .05) decreased. Complement component C3 did not change but C4 was increased. The absolute lymphocyte count decreased but the OKT4:OKT8 ratio was unchanged from controls. A decreased lymphocyte response to all mitogens occurred early and became more severely depressed near death. IL-2 caused a complete or partial restoration of the response to the mitogens CON A and PHA. Both the humoral and cell mediated immune responses are affected in SAIDS. The role of IL-2 in this immune defect must be studied further.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Immunologic alterations in monkeys with simian acquired immunodeficiency syndrome (SAIDS).

Levels of lymphocyte responsiveness to T- and B-cell-specific mitogens and expressions of Ia, T4, T8, and T11 surface markers were monitored during the course of Simian acquired immunodeficiency syndrome (SAIDS) in four Rhesus macaques that either died or became ill and survived. The monkey that died showed progressively suppressed responses to concanavalin A (Con A), phytohemagglutinin (PHA), pokeweed mitogen (PWM), and Staphylococcus aureus Cowan I strain (SAC) through the time of death (5 1/2 weeks). For the three animals that survived, the responses of peripheral blood mononuclear cell (PBMC) to the same mitogens were decreased significantly during the period 4-6 weeks after inoculation. Levels of Ia-bearing cells in the PBMC population were markedly reduced in the moribund monkey but were not significantly decreased in the three survivors. There was no significant change in the percentage of T11-bearing cells in any of the study animals. The ratio of T4- and T8-positive cells did not vary significantly during the 18 weeks of observation in any of the animals. The infected animals showed other evidence of immunosuppression including neutropenia, lymphopenia, and depletion of lymphocytes in lymph nodes. The animal that had progressive disease and death also had Kaposi-like lesions and staphylococcal septicemia. These results indicated that in vitro evidence of immunosuppression due to SAIDS appears within a few weeks after infection and this may progress in animals that die.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Improved separation of rhesus monkey lymphocytes with Percoll.

The total yield and the proportions of Rhesus monkey peripheral blood mononuclear cells (PBMC) with detectable T4, T8, T11 and Ia markers that were purified by density gradient centrifugation through solutions of polyvinyl pyrrolidone (Percoll) were significantly greater than those found in PBMC suspensions obtained by using Ficoll-Hypaque. The percentages of recovery of PBMC and of cells expressing the above markers were lowest among PBMC isolated with a Ficoll-Hypaque mixture of density 1.077 and highest among PBMC obtained by using a solution of Percoll of density 1.077. Percoll of density 1.077 was also better than Ficoll-Hypaque in that it yielded PBMC with the lowest levels of erythrocyte (less than 1%) and granulocyte (less than 1%) contamination. The reduced levels of PBMC with detectable markers appeared to result from an effect of either Ficoll or Hypaque on the lymphocytes rather than from loss of lymphocyte subpopulations since higher proportions of cells bearing T4, T8, T11 and Ia were found when PBMC were isolated with a solution of Percoll which yielded a percentage of PBMC as low as that recovered with Ficoll-Hypaque. Altered marker expression by cells obtained with Ficoll-Hypaque was not seen with similarly prepared human PBMC.

Animals↗
PubMed1984

The relation of cytomegalovirus and Epstein-Barr virus antibodies to T-cell subsets in homosexually active men.

Eighty-nine homosexual men participated in a study of sexual practices, T-cell subsets, and antibody titers to cytomegalovirus (CMV) and Epstein-Barr virus (EBV). The prevalence of antibody to CMV was 96% and to EBV, 94%. Titers to CMV were higher in those practicing receptive anal intercourse. The CMV antibody titers were positively correlated with the T-helper/suppressor ratio, number of partners and venereal disease episodes, number of T-suppressor cells, and EBV titers. Twelve percent of the participants had a low ratio only, 18% T-suppressor augmentation, and 3% T-helper deficiency. The CMV titer and prevalence of receptive anal intercourse were higher in those with a low ratio only, T-suppressor augmentation, and T-helper deficiency. These results suggest that CMV infection is acquired through receptive anal intercourse and is associated with an increase in T-suppressor cells and, in some persons, a decrease in T-helper cells.

Adult↗
PubMed1984

Transmission of simian acquired immunodeficiency syndrome (SAIDS) with blood or filtered plasma.

Simian acquired immunodeficiency syndrome (SAIDS), a disease clinically and pathologically similar to acquired immunodeficiency syndrome in humans, was transmitted from diseased rhesus monkeys (Macaca mulatta) to normal monkeys by inoculation with heparinized whole blood or plasma that had been passed through filters of 0.45 micrometer pore size. This suggests that the causative agent is small and most probably a virus. No viruses, however, were isolated by standard cell culture techniques from the blood or filtered plasma which caused SAIDS. Both cellular and humoral immunity were markedly depressed in animals with advanced SAIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Humoral and cell-mediated immune responses to herpesvirus antigens during pregnancy--a longitudinal study.

Humoral and cellular immune responses were studied during the second trimester, third trimester, and postpartum periods in 11 pregnant women and in nonpregnant control women. Complement fixing (CF) and indirect hemagglutinating antibody (IHA) titers for herpes simplex type 1 (HSV-1), herpes simplex type 2 (HSV-2), and cytomegalovirus (CMV) were determined. Cellular response was measured by [3H]thymidine uptake by stimulated lymphocytes. Phytohemagglutinin (PHA), HSV-1, HSV-2, and CMV antigens were used as stimulants. No differences in the mean titers of CF and IHA antibodies were found. The cellular response to PHA had a transient decrease (P less than 0.02) during the third trimester. The cellular response to CMV was significantly lower during the second and third trimesters. A diminished response to HSV-1 antigen was observed during the second and third trimesters; the cellular response to HSV-2, though reduced, was not significantly altered during pregnancy. These data indicate a suppression of cellular responses to various herpesviruses and PHA during pregnancy.

Antigens, Viral↗
PubMed1984

Evaluation of various plastic microtiter plates with measles, toxoplasma, and gamma globulin antigens in enzyme-linked immunosorbent assays.

Seventeen lots of microtiter plates which differed in lot, batch, plastic type, or manufacturer were evaluated as solid-phase carriers in enzyme-linked immunosorbent assays for antibodies to measles, toxoplasma, and human gamma globulin. Most plates of polystyrene or polyvinyl chloride were found to give acceptable binding. The final choice depended on the antigen to be attached. Variations in binding between lots, batches, and types of plastic were found. Well-to-well variation was found to be of greater statistical significance than edge effect and should be a consideration in selection of a plate lot for enzyme-linked immunosorbent assays. Lots of plates should be pretested by the investigator to determine whether there is good binding of the antigen to be used and whether there is low plate-to-plate and well-to-well variation.

Antibodies↗
PubMed1984

Polycarbonate-coated microsticks as solid-phase carriers in an enzyme-linked immunosorbent assay for rubella antibody.

We evaluated the use of microsticks as solid-phase carriers in an enzyme-linked immunosorbent assay for rubella antibody. The microstick enzyme-linked immunosorbent assay was found to be equal in sensitivity to plate and disk enzyme-linked immunosorbent assays and presumably more sensitive than hemagglutination and immunofluorescence assays. The microstick as a solid-phase carrier offers advantages over both plate and bead carriers.

Antibodies, Viral↗
PubMed1984

Serologic study by enzyme-linked immunosorbent assay of the IgM antibody response in the patas monkey following experimental simian varicella virus infection.

The time course of IgM and IgG antibody appearance in sera following experimental simian varicella virus infection in the patas monkey was studied. Serum IgM and IgG antibody to Delta herpes virus (DHV) were measured by a double indirect and indirect ELISA test, respectively. IgM antibody was detected 5-8 days postinfection (p.i.) and IgG antibody was present 10-14 days p.i., which was 5-7 days after IgM. Viremia preceded detectable IgM antibody by 2 days. Sucrose gradient separation of serum IgM and IgG was carried out to determine whether IgG competed significantly with IgM. Results of these studies indicated that competition by IgG with IgM antibody did not occur except when IgM had declined to a low level some 40 days p.i. Comparison of the double indirect ELISA test with a double indirect immunofluorescent antibody test for detection of IgM antibody to DHV antigen indicated the ELISA test was more sensitive.

Animals↗
PubMed1984

Kinetics of virus-specific IgG and IgM antibody response in patas monkeys experimentally infected with Delta herpesvirus by enzyme-linked immunosorbent assay.

The kinetics of virus-specific IgG and IgM antibody response in patas monkeys experimentally infected with Delta herpesvirus (DHV), was studied using enzyme-linked immunosorbent assay (ELISA). An indirect ELISA (IE) test was used for DHV IgG determination, whereas a "double sandwich" (triple antibody layer) ELISA (DSE) test was found to be very sensitive for DHV IgM detection. In DSE test DHV IgG appeared to interfere with IgM determination only in sera containing DHV IgG levels at least 100 times higher than IgM. IgM antibodies appeared 5-8 days after monkey infection, reached a peak titer in 5-7 days, and after 7 days started to drop in titer and disappeared within two months. IgG antibodies appeared 5 days later than IgM, reaching the plateau in the following 7 days and then remaining stable for at least 2 months. Experimental infection of the patas monkey with DHV appears to be a good animal model for human varicella. IE for IgG and DSE for IgM detection are sensitive ELISA tests for determination of the immune response to DHV infection in patas monkeys.

Animals↗
PubMed1984

Genital herpes infection in pregnant women near term.

A study of 215 middle income, predominantly white, suburban women for herpes simplex virus infection revealed that ten (4.6%) had positive herpes cultures near term and thus were at risk for transmission of herpes simplex virus to their newborn. Eight of these women had a previous history of herpes simplex virus infection, and seven of the eight had lesions suggestive of herpes simplex virus at the time of study. Only one patient had lesions at delivery. On the basis of past history of genital herpes or partners with herpes, 25 of the 215 women were at high risk for genital herpes near term. Thus, careful questioning identified a high-risk group of 25 patients in which eight (32%) were shedding virus near term, and this group included the majority (eight of ten) of the herpes simplex virus-infected women in the study population. There were no cases of neonatal herpes in the children born from the 215 pregnancies.

Adolescent↗
PubMed1984

Clinical features of simian acquired immunodeficiency syndrome (SAIDS) in rhesus monkeys.

A syndrome of acquired immunodeficiency has been identified in a group of rhesus monkeys (Macaca mulatta) which died at the California Primate Research Center. Clinical evaluation of these animals revealed that 50% or more had lymphadenopathy, weight loss, and diarrhea. At least 30% had splenomegaly, fever, cutaneous abscesses and/or arthritis/myositis. Two animals had fibrosarcomas. Anemia was seen in 19 animals, lymphopenia in 14, granulocytopenia in four and thrombocytopenia in three. Hepatitis was diagnosed histopathologically in 13. Electrophoresis revealed hypoproteinemia, hypoalbuminemia and hypogammaglobulinemia. Numerous bacterial, protozoal, and viral agents were identified including cytomegalovirus and leukocyte-associated herpesvirus. Pathologic lesions included severe post-reactive depletion of lymphocytes in germinal centers and paracortical regions of lymph nodes. Clinical and pathologic changes indicate an acquired immunodeficiency syndrome which has some similarities to AIDS in humans. This disease in monkeys may provide a model for studying that disease.

Acquired Immunodeficiency Syndrome↗
PubMed1983

Survival of herpes simplex virus in water specimens collected from hot tubs in spa facilities and on plastic surfaces.

Several health spas were closed temporarily because of possible nonvenereal spread of herpes simplex virus (HSV) in spa water at these facilities. We collected water specimens from two health spas and studied them for (1) the presence of HSV; (2) bromine (Br2), chlorine (Cl2), and pH levels; and (3) the ability of HSV to survive in water. No HSV could be isolated from the spa water specimens. Spa water had high levels of Cl2 and Br2, tap water specimens had low levels of Cl2, and distilled water had no detectable Cl2 or Br2. The addition of spa water to laboratory stock virus immediately inactivated the virus. The HSV survived four hours in the tap water and 24 hours in distilled water. The survival of HSV appeared to be related to the free halogen content of water. To approximate the conditions of survival of HSV on plastic-coated benches and seats in spa facilities, HSV was placed on plastic surfaces in a humid atmosphere at 37 to 40 degrees C. The virus was found to survive up to 4.5 hours under these conditions. The survival of HSV from human lesions may be different due to the presence of tissue secretions and proteins. Furthermore, transmission may require other factors, such as rubbing of skin or penetration through abrasions. However, survival of significant amounts of virus for 4.5 hours on plastic surfaces suggests that fomites such as these may be nonvenereal routes of HSV transmission.

Baths↗
PubMed1983

Experimental transmission of simian acquired immunodeficiency syndrome (SAIDS) and Kaposi-like skin lesions.

A disease that is similar to human AIDS may occur in monkeys. Simian AIDS (SAIDS) was experimentally transmitted from 2 rhesus monkeys dying of the disease to 4 cytomegalovirus (CMV) antibody-negative rhesus monkeys. The inocula consisted of the supernatant fluid from 10% homogenates of various tissues with or without buffy-coat cells from blood. Lymphadenopathy, splenomegaly, neutropenia, polymyositis, and other signs of the disease appeared in recipients within a few weeks after inoculation. Two animals developed Kaposi-like "patch" and "plaque" skin lesions and one died of sepsis and profound lymphoid depletion. A second animal also died with lymphoid depletion. All animals became infected with CMV but antibody levels were low in two animals, appeared and then disappeared in one, and never developed in the second monkey which died.

Acquired Immunodeficiency Syndrome↗