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L Pedneault

Publications and source records attributed to L Pedneault.

28 records · Page 2Linked to original sources
PubMed1994

Comparison of novel synthetic peptide-based DETECT-RUBELLA enzyme immunoassays with Enzygnost and IMx for detection of rubella-specific immunoglobulin G.

Enzyme immunoassays (EIAs) using synthetic peptides SP-E1 and SP-E1E2 (DETECT-RUBELLA [Bio-Chem]) were compared with two viral lysate-based EIAs (Enzygnost [Behring] and IMx [Abbott]) for the detection of rubella virus-specific immunoglobulin G antibodies. Sensitivities of 94.7, 100, 98.6, and 100% and specificities of 100, 97.4, 100, and 73.7% were found for the SP-E1, SP-E1E2, Enzygnost, and IMx EIAs, respectively.

Antibodies, Viral↗
PubMed1993

Comparison of polymerase chain reaction and standard Southern blotting for the detection of Epstein-Barr virus DNA in various biopsy specimens.

The sensitivity of the polymerase chain reaction (PCR) assay was compared to that of standard Southern blotting (SB) hybridization for detecting the presence of Epstein-Barr virus (EBV) genomes in biopsy samples from 43 patients with a variety of lymphoproliferative disorders. Two pairs of oligonucleotide primers from the first BamHI M and R leftward reading frames (BMLF1 and BRLF1) of EBV were chosen to amplify DNA. The resulting PCR products were analyzed by gel electrophoresis, transfer and hybridization. Restriction enzyme digestion was used to confirm the specificity of the amplified fragment. EBV DNA was found in 38 of 43 patients, as compared with 9 of 43 patients with the Southern technique. No amplified product was detected with other viruses from the Herpes family, nor with human genomic DNA from healthy adults using the same two sets of primers. These results indicate that EBV can be detected in a greater number of lymphoproliferative lesions than previously appreciated. The implications of these findings are discussed.

Adolescent↗
PubMed1993

Comparison of four enzyme immunoassays for the detection of cytomegalovirus IgG antibodies.

Four commercial enzyme immunoassays (EIA), namely the Behring Enzygnost EIA (BE-EIA), Abbott IMx, Whittaker CMV STAT Test Kit and Diamedix assay, were evaluated for the detection of CMV IgG. The methods were compared as to sensitivity, specificity, positive and negative predictive values, global agreement, ease of performance and, for a small number of specimens, reproducibility. Discordant results were resolved by using the Gull CMV indirect fluorescent antibody (IFA) method. Our data suggest that all four assays were valuable screening tools for the detection of CMV IgG based on their high sensitivity and high negative predictive value. However, differences were noted in the reproducibility level and in the incidence of false-positive, equivocal and nonspecific results regarding certain tests in particular. In our hands, the Abbott IMx and the BE-EIA ranked high in the performance characteristics for a good screening test, yet the Abbott IMx offers the added advantages of being the easiest to perform and having the most rapid turnaround time.

Journal Article↗
PubMed1993

Comparison of a whole-virus enzyme immunoassay (EIA) with a peptide-based EIA for detecting rubella virus immunoglobulin G antibodies following rubella vaccination.

A total of 250 human serum samples were tested for rubella virus immunoglobulin G antibodies by two enzyme immunoassays (EIAs), one using whole rubella virus antigen and the other based on the use of synthetic peptide antigen. The samples were taken from 125 volunteers before and after their immunization with the RA 27/3 rubella vaccine. This study indicates that a synthetic peptide-based EIA can favorably replace current viral lysate-based EIAs to detect rubella virus antibodies following immunization. Because the synthetic peptide used in this newly developed EIA represents a putative neutralization epitope of the rubella virus, it could also be instrumental in determining rubella immune status and in assessing vaccine program efficiency.

Adult↗
PubMed1992

Detection of Epstein-Barr virus in the brain by the polymerase chain reaction.

Epstein-Barr virus (EBV) has been implicated in a variety of central nervous system syndromes. In a few well-studied patients, EBV has been detected by viral isolation or EBV DNA has been found by Southern hybridization analysis. Using polymerase chain reaction, we evaluated brain biopsy specimens from 24 patients for the presence of EBV genomes. EBV DNA was found in brain specimens from 18 patients in whom presence of the virus in the brain was suspected clinically or on the basis of serological tests. Six patients had acquired immunodeficiency syndrome; 2 were kidney transplant recipients. Brain specimens from 4 patients with encephalitis due to other herpes group viruses and from a patient with metabolic encephalopathy were negative for EBV DNA as determined by polymerase chain reaction. The findings indicate a need to evaluate the role of EBV in diverse neurological syndromes, especially those occurring in immunodeficient hosts.

Adolescent↗
PubMed1991

Immunoblot analyses of the serologic response to Aspergillus fumigatus antigens in experimental invasive aspergillosis.

The antibody response to Aspergillus fumigatus proteins was studied by the immunoblot technique in a rabbit model of invasive aspergillosis. Components of an A. fumigatus mycelial homogenate homogenate unbound by concanavalin A-Sepharose 4B chromatography were fractionated using SDS-PAGE and transferred to nitrocellulose papers. The protein fraction was probed with serial sera obtained from immunosuppressed or nonimmunosuppressed rabbits inoculated intravenously with saline or graded inocula of A. fumigatus conidia. Seroconversion against antigens of 41, 54, and 71 kDa was demonstrated in 7 (50%), 3 (21%), and 3 (21%) of 14 infected animals that survived greater than or equal to 10 days. Antibodies against the three antigens were detected in 4 (12.5%), 19 (59%), and 14 (44%) of 32 rabbits before immunosuppression or infection. Two-dimensional immunoblotting revealed that the 41-, 54-, and 71-kDa antigens were derived in denaturing conditions from a single component resolved in nondenaturing polyacrylamide gel electrophoresis.

Animals↗
PubMed1990

Production and characterization of monoclonal antibodies to cell wall antigens of Aspergillus fumigatus.

Two murine monoclonal antibodies (MAbs) against Aspergillus fumigatus were produced and characterized. Splenocytes from cell wall-immunized BALB/c mice were fused with SP2/0 myeloma cells. The hybridomas were screened with a cold alkali (CA) extract of mycelium containing protein, mannose, and galactose, and two MAbs of the immunoglobulin M class were purified from ascites fluid. MAbs 1 and 40 were characterized by double immunodiffusion against CA antigen, indirect enzyme immunoassay with mannans of Candida albicans serotypes A or B or Candida tropicalis, indirect immunofluorescence with C. albicans- or A. fumigatus-infected tissues, indirect immunofluorescence with smears of other pathogenic fungi, Western blotting (immunoblotting) with the lectin concanavalin A or BS-1 from the seeds of Bandeirea simplicifolia, and immunoelectron microscopy. MAb 1 did not cross-react with Candida mannan and recognized a periodate-sensitive, pronase- and heat-resistant epitope in CA antigen and three mannose- and galactose-containing components (80, 62, and 49 kilodaltons) of a mycelial homogenate. Immunoelectron microscopy demonstrated binding of MAb 1 to the inner cell wall and intracellular membranes of hyphae and conidia of A. fumigatus. Circulating antigen was detected in experimental invasive aspergillosis by inhibition enzyme immunoassay with MAb 1 and CA antigen. MAb 40 was a nonprecipitating antibody cross-reactive with Candida species, and competition for an epitope located diffusely in the cell wall of A. fumigatus hyphae was demonstrated by incubating MAb 40 with mannan of C. albicans serotype A. These results suggest that MAb 1 recognizes immunodominant oligogalactoside side chains of A. fumigatus galactomannan, while MAb 40 binds to mannopyranosyl side chains common to A. fumigatus galactomannan and C. albicans mannan.

Animals↗
PubMed1990

Long term treatment with CV 205-502 in patients with prolactin-secreting pituitary macroadenomas.

CV 205-502, a new long-acting nonergot dopamine agonist, was given to 15 patients (6 women and 9 men) with PRL-secreting pituitary macroadenomas. The compound was administered in a single daily dose for a period of 6-12 months. The treatment resulted in normalization of plasma PRL levels (less than or equal to 20 micrograms/L) in 5 of 6 women at a mean dose of 135 micrograms (range, 75-300 micrograms) and in 6 of 9 men at a mean dose of 192 micrograms (range, 75-300 micrograms). Among patients for whom computed tomographic scans were available before and after at least 6 months of therapy, definite tumor shrinkage occurred in 6 of 7 patients. Libido was improved in 5 of 6 women and in 6 of 8 men, galactorrhea disappeared in all cases (3 women and 1 man) and menses resumed in 3 of 5 women. Plasma testosterone rose to normal levels in 3 of 6 men who were not receiving testosterone injections. The PRL response to TRH was blunted in 4 of 6 patients with normalized basal PRL. Serum total cholesterol was reduced by CV 205-502 treatment in women from 5.35 +/- 0.49 to 4.63 +/- 0.51 mmol/L (P = 0.031) and in men from 5.93 +/- 0.89 to 5.28 +/- 0.82 mmol/L (P = 0.045). Side-effects included mainly headache, nausea, and dizziness. One side-effect or more occurred transiently and with mild intensity in 14 patients. No patient discontinued the therapy because of side-effects. In conclusion, CV 205-502 appears to be a safe and valuable compound in the treatment of patients with PRL-secreting macroadenomas.

Adult↗
PubMed1985

Effect of aminoglycosides on the disposition of thyroid hormones and thyroglobulin.

Our study was designed to confirm the potential effects of three aminoglycosides on the disposition of thyroid hormones. Twenty-seven patients diagnosed with either cellulitis (n = 19), chronic osteitis (n = 4), or an abscess (n = 4) were selected. Thirteen patients received tobramycin, 60 to 100 mg iv q. 8 h., plus cloxacillin, 1 gm iv q. 4 h.; seven patients received netilmicin, 40 to 120 mg iv q. 8 h., plus cloxacillin, 1 gm iv q. 4 h.; and seven patients received either cloxacillin, 1.5 gm iv q. 4 h., or cefoperazone, 2 to 4 gm iv q. 12 h. for at least 7 days. Another group of six normal subjects received neomycin, 0.5 gm po q. 6 h. for 7 days. All these subjects had normal thyroid function before antibiotic dosing and none had thyroid function abnormalities. Tobramycin and cloxacillin/cefoperazone did not influence thyroid function. Netilmicin decreased the total serum concentrations of triiodothyronine (T3) from 114 +/- 9 to 75 +/- 7 ng/dl (P less than 0.01), probably because of increased clearance, as the T3 free fraction increased from 0.43% +/- 0.02% to 0.49% +/- 0.02% (P less than 0.05). Thyroxine (T4) and reverse T3 (rT3) levels were not affected. Neomycin decreased T3 levels from 104 +/- 8 to 92 +/- 7 ng/dl (P less than 0.05) and the serum concentrations of thyroglobulin from 17.3 +/- 2.0 to 11.7 +/- 2.0 ng/ml (P less than 0.001). Because T4 and rT3 levels did not change, our results suggest that neomycin may have directly affected the gland. We conclude that some aminoglycosides can alter the disposition of thyroid hormones.

Adult↗