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A Jeanson

Publications and source records attributed to A Jeanson.

7 recordsLinked to original sources
PubMed1994

Assessment of the new immunological test Hemoblot for detecting occult blood in faeces.

Hemoblot, a new immunological faecal occult blood test, produced by Gamma, Angleur, Belgium, was characterized and compared with another immunological test (HemeSelect, SmithKline Diagnostics, USA) and with a guaiac test (Hemoccult II, SmithKline Diagnostics). The analytical sensitivity of Hemoblot is 0.15 mg haemoglobin/g faeces and the test is specific for human haemoglobin. In addition, 135 symptomatic patients who had to undergo a colonoscopy were tested using the three tests. Two criteria were considered for the analysis: (1) the blood criterion: any pathology likely to cause colorectal or other bleeding; and (2) the precancerous-cancerous criterion: the pathology being either a colorectal polyp > 0.5 cm or a colorectal cancer. Considering both criteria, the sensitivity of Hemoblot was significantly higher than the sensitivity of Hemoccult: 38% and 23%, respectively, for the blood criterion; and 54% and 29% for the precancerous-cancerous criterion. Sensitivity and specificity did not differ statistically between Hemoblot and HemeSelect but Hemoblot was faster and simpler to perform. It could be widely used in mass screening.

Adult↗
PubMed1988

Preparation of reproducible alkaline phosphatase-antibody conjugates for enzyme immunoassay using a heterobifunctional linking agent.

Conjugates of alkaline phosphatase (AP) and mouse monoclonal immunoglobulins G (IgG) were prepared by means of the heterobifunctional linker, N-succinimidyl 3-(2-pyridyldithio)-propionate. The efficiency of such conjugates can be improved by optimizing the degree of substitution of IgG and AP. We have determined conditions yielding better performing conjugates than those synthesized by methods described previously. Moreover, the results obtained with the technique presented here are quite reproducible with all four monoclonal antibodies tested.

Alkaline Phosphatase↗
PubMed1988

Comparison of conjugation procedures for the preparation of monoclonal antibody-enzyme conjugates.

Four monoclonal antibodies belonging to different subclasses and with differing isoelectric points were coupled to horseradish peroxidase (HRP) and alkaline phosphatase (AP) using various conjugation procedures. The conjugates were tested by enzyme immunoassay and their efficiency was characterized by the antibody and enzyme concentrations needed to obtain an arbitrary OD value. The suitability of antibody for conjugation through NH2 groups was tested by fluorodinitrobenzene (FDNB). HRP conjugates were produced by two variants of the sodium periodate procedure and two variants of the glutaraldehyde method, as well as by the heterobifunctional linker N-succinimidyl 3-(2-pyridyldithio)propionate (SPDP). Two of the four antibodies were coupled by a third variant of the periodate method, through their carbohydrate moieties. The periodate-mediated conjugations, using sugar moieties on the enzyme, provided the most efficient HRP conjugates, regardless of the antibody subclass or isoelectric point. The glutaraldehyde procedures consistently gave the worst results. AP conjugates were prepared using the same methods. The most efficient and reproducible AP conjugates with all four monoclonal antibodies were obtained using the SPDP procedure. The efficiency of the other methods differed from one antibody to another.

Alkaline Phosphatase↗
PubMed1983

[Acute hematogenic interstitial nephritis of urinary origin: an unrecognized factor in the exacerbation of chronic kidney failure].

Hypertension, phosphate retention, hyperfiltration hyalinosis and the natural course of the underlying are well known factors leading to progression of chronic renal failure. Acute bacterial interstitial nephritis occurring in a previously diseased kidney, although well documented in experimental animals, has not been shown to aggravate chronic renal failure in man. We report on 3 cases of acute suppurative interstitial nephritis, due to E. coli urinary infection complicated by septicemia. All had rapid aggravation of previously mild renal failure secondary to chronic interstitial nephritis. Sepsis originated from the urinary tract which in 2 instances had been temporarily obstructed. Renal biopsy disclosed a diffuse interstitial infiltrate containing numerous polymorphonuclear leukocytes. This was superimposed on chronic tubular and interstitial lesions. In 1 case there were glomerular lesions with crescents and mesangial C3 deposits. A 2nd biopsy performed in 2 cases was of prognostic interest. In one case it showed active lesions and the necessity of continuing the treatment and in the other a satisfactory healing allowing cessation of therapy. Treatment was guided by antibiograms, the clinical and urinary signs of activity, renal biopsy findings and antibiotics known to be concentrated in renal tissue. The duration of treatment seemed important for the regression of acute renal lesions. Hematogenous bacterial interstitial nephritis should be considered as a possible cause of aggravation in chronic renal failure.

Acute Disease↗
PubMed1980

The action of leukotriene B4 (LTB4) on the lung.

The actions of leukotriene B4 (LTB4), a member of a newly discovered pathway of metabolism of arachidonic acid, were investigated both on the guinea-pig perfused lung preparation and on the parenchymal strip and compared to histamine and Slow Reacting Substance of Anaphylaxis (SRS-A). LTB was prepared from human polymorphonuclear leukocytes, extracted and purified by chromatography (Silicic acid and HPLC) and its purity was determined by gas chromatography and mass spectrometry. LTB4 is three times more potent than histamine (molar concentration) to contract the parenchymal strips and the contraction to LTB4 as well as to SRS-A lasted longer. The contraction to LTB4 is blocked by indomethacin (20 micrograms/ml), reduced by polyphloretin phosphate (50 micrograms/ml) and unaffected by FPL-55712 (1 micrograms/ml). Following its injection in the pulmonary artery of a perfused lung, LTB4 (1 microgram) induced the release of RCS (Rabbit Aorta Contracting Substance: a mixture of prostaglandins and thromboxanes) which can be abolished by indomethacin (1 microgram/ml). These findings suggest (a) that in the lung, LTB4 is a myotropic agent three times more powerful than histamine (b) that LTB4 stimulated a receptor which is different of histamine of SRS-A receptors, and (c) that its contractile action in the lung is mediated by prostaglandins and thromboxanes.

Animals↗