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Biomedical subjects

D Armstrong

Publications and source records attributed to D Armstrong.

At least 577 records · Page 32Linked to original sources
PubMed1981

Candida antigenemia, as detected by passive hemagglutination inhibition, in patients with disseminated candidiasis or Candida colonization.

A passive hemagglutination inhibition assay was studied by using a hyperimmune serum from rabbits immunized with whole yeast cells (Candida albicans group A). This technique was effective at detecting small amounts of laboratory-prepared mannan or a whole-cell extract of C. albicans. Of 32 patients with documented disseminated candidiasis that were tested, 19 showed evidence of circulating antigen by passive hemagglutination inhibition. Three of these patients showed only partial, rather than complete, inhibition. Among 22 colonized patients, 4 showed partial inhibition, and none of 49 normal controls demonstrated inhibition. All of the sera were tested for antibody by agglutination, immunodiffusion, and passive hemagglutination. This last technique added increased sensitivity, but not specificity, to the standard tests already in use. Fourfold or greater titer rises by passive hemagglutination occurred in fewer than one-third of patients with invasive candidiasis and developed in more than one-half of patients who were colonized and did not require systemic anticandida therapy.

Antibodies, Fungal↗
PubMed1981

Rate of arabinitol production by pathogenic yeast species.

D-Arabinitol is a five-carbon polyol that is produced by many fungi. Detection of the metabolite has been reported in serum from patients with invasive candidiasis. We studied the production and assimilation of arabinitol by 46 clinical isolates of yeast species. Cultures of isolates of Candida albicans (9 strains), Candida tropicalis (12 strains), Candida parapsilosis (13 strains), Candida krusei (4 strains), Candida pseudotropicalis (3 strains), Torulopsis glabrata (3 strains), and Cryptococcus neoformans (2 strains) were assayed by gas-liquid chromatography. Yeast cells were cultured at 34 degrees C in yeast nitrogen base with 3.0 g of glucose per liter. At 1.5- to 3-h intervals, cells were counted and glucose and arabinitol were measured in media filtrates. The levels of arabinitol in cultures with 7.5 X 10(6) yeast cells per ml were compared. The mean concentrations of the metabolite in C. albicans, C. tropicalis, C. parapsilosis, and C. pseudotropicalis cultures wee 14.1, 1.6, 8.4, and 5.5 micrograms/ml, respectively. No arabinitol was detected in cultures of C. krusei, T. glabrata, or C. neoformans.

Candida↗
PubMed1981

Comparative recovery of fungi from biphasic and conventional blood culture media.

A brain heart infusion broth and agar biphasic bottle was compared with a vented broth brain heart infusion bottle for the recovery of fungi from blood. A total of 40 fungi, all yeasts, were recovered from 5,000 blood cultures. The biphasic bottle slightly increased the overall recovery of six species of yeasts. In addition, yeasts were first detected more often in the biphasic bottle (73%) than in the vented broth bottle (38%). A routine early (6- to 24-h) or late (5-day) subculture of macroscopically negative cultures may not be required for yeast isolation when a biphasic medium is used. Of the yeasts initially detected in the biphasic medium, 83% were seen to be growing on the agar slant. Only four were detected from a 24-h subculture, a Candida glabrata of questionable clinical significance, was recovered after our routine blood culture period of 7 days; however, other fungi, not recovered in this study, require extended incubation periods.

Blood↗
PubMed1981

The distribution of peroxide regulating enzymes in the canine eye.

The retina and rod outer segments (ROS), rich in unsaturated lipids, are highly susceptible to autoxidation via free radical mechanisms. In the canine eye, four enzymes, i.e.; p-phenylenediamine (PPD) peroxidase, glutathione peroxidases, catalase and superoxide dismutase which are involved in the production or degradation of peroxides, were measured. All enzymes were present in the retina, ciliary body and iris, but differed in concentration. Superoxide dismutase showed high activity in the ROS. In the retinal pigment epithelium (RPE) a peroxidase utilizing PPD as cosubstrate and superoxide dismutase were both present. The former enzyme was found equally distributed between soluble and insoluble forms. A pigment granule fraction from the RPE only contained PPD-peroxidase. The compartmentalization of peroxide regulating enzymes in the eye is striking. Whereas the retina seems well protected against superoxide free radicals and hydrogen peroxide by virtue of superoxide dismutase, peroxidases and catalase activities, the ROS are only protected by superoxide dismutase. Therefore, after phagocytosis of the ROS, any peroxidized lipids, organic peroxides, or unconverted superoxide radicals contained within the ROS, must be detoxified by a specific RPE peroxidase and superoxide dismutase. Hydrogen peroxide or other peroxidized compounds apparently are not degraded by glutathione peroxidases or catalase, since these enzymes were not measurable in our RPE preparations. The role of antioxidative enzymes in the eye, which retard peroxide and free radical information, appears to be specific and regional.

Animals↗
PubMed1981

Prophylactic trimethoprim-sulfamethoxazole during consolidation chemotherapy for acute leukemia: a controlled trial.

We conducted a prospective, controlled, randomized trial of oral trimethoprim-sulfamethoxazole treatment in patients with acute leukemia receiving consolidation chemotherapy. We followed 14 treatment patients during 33 episodes and 15 control patients during 34 episodes of granulocytopenia (less than 1000 granulocytes/mm3). We found no significant difference in the incidence of febrile episodes (13 in treatment group versus 14 in control group), hospitalizations to treat fever or infection (10 versus 12), number of documented infections (eight versus 10), number of septicemias (one versus two), or mean duration of hospital stay to treat fever or infection (8.9 versus 9.2 days) in the two groups. There was little colonization with organisms resistant to trimethoprim-sulfamethoxazole, including Candida, in either group. Prophylactic trimethoprim-sulfamethoxazole did not significantly reduce the incidence of fever, hospitalization, or infection in granulocytopenic patients during consolidation chemotherapy.

Acute Disease↗
PubMed1980

Antibody responses to mycobacterial antigens in patients immunized with BCG for the treatment of neoplastic disease.

Precipitin and agglutination antibody response to antigens of Mycobacterium tuberculosis was measured in 43 patients with neoplastic disease who were treated with weekly BCG or intratumor BCG vaccination. Resuspended freeze-dried Tice vaccine was shown to contain soluble mycobacterial antigens. Fourteen patients receiving weekly BCG vaccination developed intense precipitin and agglutination antibody response over the course of several months. Twenty-nine patients receiving intratumor and oral vaccination developed less intense antibody response. Twenty-one of 28 purified protein derivative (PPD)-negative patients converted their PPD. No correlation between antibody, PPD response and antitumor effect could be identified. The importance of identifying the soluble antigen in BCG and of defining the humoral response to purified antigens is discussed.

Agglutination Tests↗
PubMed1980

Serum immunoglobulin levels in childhood Hodgkin's disease. Effect of splenectomy and long-term follow-up.

Children with Hodgkin's disease had significantly elevated serum IgG and IgA levels but normal IgM and IgD levels when compared with healthy age- and sex-matched controls. The increased serum IgG and IgA levels occurred in all four clinical stages of Hodgkin's disease but were not related to histologic cell type. Following staging splenectomy, serum IgG, IgA, and IgD levels fell by 20% in patients who recieved radiation therapy then returned to preoperative levels; by contrast, serum IgM levels fell by 50% and remained there for at least 36 months. Patients who received chemotherapy had a persistent decline in serum levels of all immunoglobulin classes by at least 40%. Thus, staging splenectomy per se appears to be at least partly responsible for the postoperative decline in serum IgM levels and this effect is enchanced by aggressive treatment of the Hodgkin's disease.

Adolescent↗
PubMed1980

Influenza immunization of children with neoplastic diseases.

During the National Influenza Immunization Program in 1976, 147 children with neoplastic diseases received Wyeth split-product bivalent influenza vaccine: A/New Jersey/8/76 (HSW1N1), A/Victoria/3/75 (H3N2). Thirteen normal siblings served as controls. Seventy-one patients received two doses of the vaccine four weeks apart. After the second injection of A/NJ/8/76, there was a difference between the response of the patients on chemotherapy and those off therapy greater than or equal to 30 days--38% vs. 76%, P less than 0.01 for four-fold rise and 26% vs. 57%, P less than 0.05 for the attainment of protective (greater than or equal to 32) hemagglutination inhibition (HI) titers. These differences were observed in both leukemia-lymphoma and solid tumor patients. There was a difference in HI titers to A/Vic/75 between patients on and off chemotherapy after a single injection, 34% vs. 71%, P less than 0.001 for a four-fold rise. After the second immunization, only 52% on, and 86% off therapy (P less than 0.05) had a four-fold rise in titers. Thirty-two percent of the patients on treatment who achieved "protective" titers did so only after the second immunization. Immunoglobulin levels and neutropenia did not correlate with the inability to obtain a four-fold rise in titers. Our findings suggest that patients on chemotherapy cannot be effectively vaccinated by a new antigen, and that single yearly boosters may be insufficient for recall of old antigens. Patients off chemotherapy greater than or equal to 30 days respond as normal controls.

Antibodies, Viral↗
PubMed1980

Cerebral embolism: local CBF and edema measured by CT scanning and Xes inhalation.

Serial CT scans were made in baboons after cerebral embolization during stable Xe inhalation for measuring local values for CBF and lambda (brain-blood partition or solubility coefficients), followed by iodine infusion for detecting blood-brain barrier (BBB) damage. Supplementary 133Xe CBF measurements were made at corresponding intervals. Persistent zones of zero flow surrounded by reduced flow were measured predominantly in subcortical regions, which showed gross and microscopic evidence of infarction at necropsy. Overlying cortex was relatively spared. Reduced lambda values attributed to edema appeared within 3--5 minutes and progressed up to 60 minutes. Damage to BBB with visible transvascular seepage of iodine began to appear 1--1 1/2 hours after embolism. In chronic animals, lambda values were persistently reduced in areas showing histologic infarction. Contralateral hemispheric CBF increased for the first 15 minutes after embolism, followed by progressive reduction after 30 minutes (diaschisis).

Afferent Pathways↗
PubMed1980

The prevalence of yeasts in clinical specimens from cancer patients.

Yeasts recovered from cancer patients during a 15-month period were speciated, and the prevalence of these isolates in various types of clinical specimens was determined. Five species, including Candida albicans, Candida tropicalis, Candida parapsilosis, Candida krusei, and Torulopsis glabrata, accounted for 97.1% of the isolates. Eighteen different species were recovered. Respiratory and urine specimens yielded 75% of the organisms. C. albicans, C. tropicalis, and C. parapsilosis were recovered in about equal frequency from blood cultures. Certain species usually were recovered from one type of specimen: Candida quilliermondii from urine, Trichosporon cutaneum and Candida pseudotropicalis from respiratory sites, and Cryptococcus neoformans from spinal fluid. Pityrosporum orbiculare was isolated only from ear and urine cultures. Most of the yeasts (95.4%) were identified within 48 hours after isolation.

Candida↗
PubMed1980

Diagnosis of invasive aspergillosis by passive hemagglutination assay of antibody.

Sheep red cells treated with concanavalin A and sensitized with a partially purified aspergillus antigen were used to detect antibody to Aspergillus by passive hemagglutination (PHA). Sera from eight patients with aspergillomas or allergic aspergillosis had PHA titers of greater than or equal to 1:800 and antibody detectable by immunodiffusion (ID). Of 122 hospitalized cancer patients without invasive aspergillosis, 118 had titers of less than or equal to 1:80, 86 of < 1:10, two of 1:160, and two of 1:320. None had antibody by ID. Antibody was detectable by PHA in sera from 12 of 14 healthy microbiology laboratory workers. Of 55 cancer patients who had sera available for testing within two weeks before diagnosis of invasive aspergillosis, 18 patients seroconverted: 13 by both PHA and ID, two by PHA alone, and three by ID alone. PHA titers rose from < 1:10 to between 1:40 and 1:1,280. In immunosuppressed patients who were at risk of developing invasive aspergillosis, the appearance of antibody correlated with the diagnosis of invasive aspergillosis.

Antibodies, Fungal↗
PubMed1980

Selective IgA deficiency and neoplasia.

From the Immunodeficiency Cancer Registry, it has appeared that there is an increasing frequency of neoplasia in individuals who have a selective absence of serum IgA. Approaching this question from another point of view, we have found that of 4,120 sera drawn in this cancer-oriented hospital, 12 sera had a total absence of IgA and 3 additional sera had less than 10 mg/dl. The incidence of IgA deficiency in a cancer hospital is thus 1 : 342 or 1 : 273, which is statistically similar to that previously found for other patient groups studied in the USA (average of two studies, 1 : 418), but it is substatistically increased over the incidence of IgA deficiency found in normal blood donors (average of five studies 1 : 1,677). Analysis of these sera by diagnostic categories showed that of 1,517 sera of patients with lymphoproliferative disorders, 6 were IgA deficient (frequency 1 : 253), and of 249 sera of patients with gastrointestinal neoplasm, 2 were IgA deficient (frequency 1 : 125). We conclude that, in the absence of IgA, certain organ systems, the gastrointestinal and lymphoid tissue may be at increased risk for malignant change and that the protective, anti-neoplastic role of IgA requires investigation.

Adult↗
PubMed1980

Haemorrhagic complications of multiple sclerosis.

Neurological exacerbations in multiple sclerosis patients are usually attributed to relapses of the disease. This report emphasises that other conditions, such as spontaneous CNS haemorrhage, may be responsible for the clinical deterioration. We describe two patients appropriately diagnosed as having multiple sclerosis who developed spontaneous CNS haemorrhage.

Adult↗