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D Sondag

Publications and source records attributed to D Sondag.

At least 37 records · Page 2Linked to original sources
PubMed1991

Influence of affinity of antibodies upon their detection by liquid phase radiobinding assay and solid phase enzyme linked immunosorbent assay. Demonstration using monoclonal antibodies raised against rDNA human proinsulin.

Hybridomas producing proinsulin antibodies were cloned by limiting dilution of cell cultures obtained by fusion of splenocytes of immunized mice with immortal myeloma cells. Some proinsulin monoclonal antibodies crossreacted with labelled insulin but none did with labelled C-peptide indicating that the involved epitopes were at one of the insulin/C-peptide junctions or included in the insulin moiety. Hybridoma supernatants were assayed for IgG concentration by a solid phase assay and for ligand binding by a radiobinding assay and an enzyme linked immunosorbent assay. The half-life of immune complexes formed with radioligand was measured and, as expected, correlated with affinity as measured by the method of Scatchard. Antibody titres determined by enzyme linked immunosorbent assay did not correlate to those measured by radiobinding assay. IgG concentration correlated to enzyme linked immunosorbent assay titres but not to radiobinding assay titres. Finally, a significant correlation was found between radiobinding assay titre and the product of enzyme linked immunosorbent assay titre by the period of immune complexes. It is concluded that, except for very low affinity antibodies, enzyme linked immunosorbent assay is a capacity assay whereas radiobinding assay is influenced by both antibody concentration and affinity. The former assay is thus best suited to detecting low affinity antibodies whereas the latter is more efficient in the presence of low levels of high affinity antibodies.

Animals↗
PubMed1991

[Mobilization of leukocytes during sub-maximal dynamic exercise].

Increase of blood leucocytes induced by a dynamic exercise has been studied in 10 adult male subjects (age: 22 +/- 2 years; body weight 73 +/- 10 kg; VO2max: 54 +/- 8 ml O2/kg.min. The exercise consisted of a 20 minutes test on a cycle ergometer at a work rate eliciting a total energy expenditure roughly equal to 80% of the maximal aerobic power (80% VO2max). During exercise the absolute number of circulating leucocytes (n Leu) increased significantly toward a maximal value reached in most cases at the end of exercise. The maximal values of n Leu--expressed as percentage of n Leu measured at rest--in the different blood leucocyte types (monocytes:n Mono; granulocytes:n GR; natural killer cells:n NK) and lymphocyte subsets (lymphocytes:n LY; lymphocytes T:n T; lymphocytes B:n B; lymphocytes T helper:n T4; lymphocytes T suppressor:n T8)--were as follows:n Mono:240%; n GR:170%; n NK:490%; n LY:220%; n T:200%; n B:190%; n T4:140%; n T8:190%. With the exception of n GR, n Leu decreased during recovery at a rate depending on the leucocyte type. The n T4/n T8 ratio, equal to 1 at rest, was reduced by about 40% during exercise. This ratio rose after exercise and reached a value equal to that measured at rest after 20 minutes recovery. In agreement with FERRY (1989), we concluded that exercise is accompanied by a selective mobilization of the different leucocyte types. The magnitude of this phenomenon and the kinetics of n Leu recuperation depend on cell types.

Adult↗
PubMed1991

[Diagnostic and therapeutic problems of aorto-enteric fistulas caused by aortic prostheses. 5 surgical cases of which 4 were successful].

The clinical characteristics, surgical treatment and therapeutic results, were surveyed in 5 cases of aorto-enteric fistulas observed in 650 abdominal aortic reconstructive operations in ten years. The fistula concerned the duodenum in two cases, the jejunum in one and the ileum in two cases. Two patients were treated by removal of the prosthesis and an axillofemoral bypass, one by an axillofemoral shunt only and the two others by repair of the graft. One patient died a few days after the operation, another eighteen months later. The prognosis of aorto-enteric fistulas after aortic reconstructive surgery is often bleak. It should be improved by an early diagnosis, supported by anamnestic history and an upper endoscopy. An aggressive surgery, whose modalities are discussed, gives maximum chances of success.

Angiography↗
PubMed1990

Clonally restricted insulin autoantibodies in a cohort of 2200 healthy blood donors.

Serum samples of 2200 blood donors were screened for anti-insulin IgG by enzyme-linked immunosorbent assay. Specificity of detected antibodies was verified by competition with an excess of insulin and observation that saturated anti-insulin IgG were no longer measurable. The upper limit of measured signal in the population was defined as the mean plus three SD. In the direct assay, 32 sera were positive. Among these, 22 (1%) contained saturable insulin antibodies (true positive) and 10 were non-saturable and considered as non-insulin-specific. The positive blood donors were requested to answer a questionnaire and according to their answers, none had ever received insulin, was a first degree relative of a Type 1 (insulin-dependent) diabetic patient or had experienced a hypoglycaemic episode. None of the 22 true positive sera detected by enzyme-immunosorbent assay bound 125-I-insulin to any significant extent. The nine sera yielding the highest signal were further characterized with regard to heavy and light chains as well as species specificity of ligand. Anti-insulin IgG from healthy blood donors contained only one heavy (gamma 1 2/9;gamma 3 7/9) and one light (kappa 8/9); lambda 1/9) chain. Three sera were human insulin specific; two were non-species-specific; the other four bound insulin in the order human = porcine greater than bovine. These results indicate that low affinity clonally restricted antibodies against insulin are present in unselected blood donors with a prevalence of 1%.

Adult↗
PubMed1990

Radioimmunoassay for albuterol using a monoclonal antibody: application for direct quantification in horse urine.

A monoclonal antibody was synthesized in mouse against the O-(3-carboxypropionyl) derivative of albuterol linked to bovine serum albumin. Isotyping of this material revealed the IgG1 class characterized by an affinity constant of 1.03 nM-1 and a density of sites of 0.55 nM. This antibody was found specific as its cross-reactivity to structurally related molecules was less than 1% except for clenbuterol (75%). A radioimmunoassay was set up with culture supernatant (final dilution 1/1000) and [3H] albuterol. The calibration curve was characterized by a maximum binding of 28%, an ED50 of 1.15 pmol per tube, the detection limit was 28.8 fmol/tube and the linearity of the response was up to 39.8 pmol/tube. This RIA method has been used for direct quantitation of albuterol in horse urine without any clean-up or extraction step.

Albuterol↗
PubMed1989

[Hepatobiliary actinomycosis. Apropos of 3 cases with pseudocancerous aspects].

Three cases of hepatobiliary actinomycosis are reported. In all cases, carcinoma was initially suspected. One patient underwent cytoaspiration under sonographic guidance. Diagnosis was obtained by autopsy in one case, laparotomy and biopsy in the other cases. Confusion with cancer is frequent in actinomycosis, especially in hepatic lesions.

Actinomycosis↗
PubMed1989

[What advice can you give to a woman having survived an acute liver steatosis in pregnancy (Sheehan disease) and who wants to get pregnant again?].

The acute fatty liver of pregnancy is a rare and potentially fatal disorder, which may complicate the third trimester of pregnancy. Early recognition of the disorder with rapid termination of the pregnancy and intensive treatment have lightened an often dismal prognosis. Maternal and fetal mortality rates are about 20-30% and 50% respectively. What advice should be given to survivors if they wish to become pregnant again? After an acute fatty liver cure, it should be noted that 21 pregnancies in 17 women were concluded without complications and these resulted in the births of normal infants. To our knowledge, no recurrences of acute fatty, liver were made known. These results probably allow a more favourable view of a new pregnancy in a woman who has survived.

Acute Disease↗
PubMed1987

Characterization of a murine monoclonal antibody specific for the human P1 blood group antigen.

Four monoclonal antibodies (MAbs) directed against the P1 blood group antigen were produced by hybridomas obtained from mouse immunized with turtle-dove avomucoid. One of the MAb (154 IX B6) selected as a blood typing reagent agglutinated native P1 and Pk1 red cells with a high titer but was inactive against native P2, Pk2 and p erythrocytes. After papain treatment the reactivity towards P1 and Pk1 erythrocytes was enhanced whereas p erythrocytes remained unreactive. A weak cross-reactivity of the MAb with the Pk antigen was suspected since enzyme-treated Pk2 erythrocytes became significantly agglutinated. Further analysis of the antibody specificity was established by binding studies using neutral glycolipids prepared from P1 and P2 erythrocytes, affinity immunoabsorbents carrying known oligosaccharide structures and hapten inhibition with synthetic oligosaccharides. The MAb bound weakly to the Gal alpha 1-4Gal structure common to P1 and Pk antigens but had a marked preference for the P1 determinant (Gal alpha 1-4 Gal beta 1-4 GlcNAc) and the binding was abolished by prior treatment of oligosaccharide antigens by alpha(not beta)-galactosidase, which supports evidence that a terminal alpha-galactose residue is involved in the blood group P1 and Pk specificities. The MAb has a slightly broader specificity than the human anti-P1 counterpart but can be used safely for routine blood typing.

Animals↗
PubMed1987

In vitro effects of thymopentin on the gamma-interferon production by peripheral blood mononuclear cells from normal subjects and from patients with rheumatoid arthritis.

The in vitro production of gamma-interferon (gamma-IFN) by peripheral blood mononuclear cells (MNC) was measured using a specific radioimmunoassay in 16 patients presenting with active rheumatoid arthritis (RA), in 14 patients with inactive disease, and in 36 control subjects (CS). Unstimulated cultures produced undetectable levels of gamma-IFN and did not incorporate tritiated thymidine. In response to phytohemagglutinin (PHA) 0.2 microgram/ml, MNC from active RA produced 9 times less, and under PHA 2.5 micrograms/ml, 4 times less gamma-IFN than did MNC from inactive RA or from CS. The uptake of tritiated thymidine was, however, similar in the 3 groups. In unstimulated cultures of the 3 groups, thymopentin (TP-5), at all concentrations tested, did not influence either the levels of gamma-IFN or the uptake of tritiated thymidine. In the presence of PHA 0.2 microgram/ml and TP-5, lambda-IFN levels were increased in CS, unchanged in inactive RA and reduced in active RA, whereas no changes were observed in the uptake of tritiated thymidine. Our results show that under our experimental conditions, TP-5 was able to increase the levels of gamma-IFN produced by normal MNC in vitro, but could not reverse the profound defect observed in active RA.

Adult↗
PubMed1987

Gerbich reactivity in 4.1 (-) hereditary elliptocytosis and protein 4.1 level in blood group Gerbich deficiency.

The membrane polypeptide composition and the blood group Gerbich phenotype of red cells from 4.1 (-) hereditary elliptocytic patients and from Gerbich-negative donors, who display two unrelated genetic abnormalities, were compared. In homozygous 4.1 (-) hereditary elliptocytosis where the primary defect was presumably the absence of the membrane skeletal protein 4.1, there was approximatively a 70% reduction in the minor sialoglycoproteins beta and gamma. This was associated with a severe reduction of blood group Gerbich reactivity as determined with both murine monoclonal and human anti-Gerbich antibodies. In the heterozygous state in the presence of one haploid set of protein 4.1 gene there was only a modest decrease in glycoproteins beta and gamma and the Gerbich serological reactivity was within normal limits. In homozygous Gerbich-negative red cells which lack glycoproteins beta and gamma but do not display elliptocytic red cells, the levels of protein 4.1 was repeatedly found within or just below the lowest values of normal controls. In the heterozygous Gerbich-negative conditions, glycoproteins beta and gamma were present in reduced amounts but the blood group Gerbich reactivity fell within normal limits since the anti-Gerbich reagents used were unable to detect a dosage effect. The amount of protein 4.1 was normal. These results add further support to the view that protein 4.1 and the sialoglycoproteins beta and gamma are physically linked in vivo which in some way serve to maintain red cell shape and integrity. Of interest was the finding that absence of protein 4.1 had a greater influence on the level of membrane glycoproteins beta and gamma than did the absence of beta and gamma glycoproteins on band 4.1.

Blood Group Antigens↗
PubMed1987

[Specific gastric localization of Wegener's disease].

We report an unusual gastric ulcer disease in a 52 year old white man which relapsed despite antacids and anti-H2 treatment. During the course of the disease, fever, weight loss, and ocular, oropharyngeal as well as systemic manifestations occurred. Gastric biopsies were normal until macrobiopsy was performed 5 months later demonstrating necrotizing granulomatous vasculitis. Further identical oropharyngeal mucosal lesions and a pulmonary infiltrate occurred supporting the diagnosis of Wegener's disease. The subsequent course was complicated by a massive hemorrhage which required total gastrectomy. Despite specific treatment with cyclophosphamide and steroids, the patient died. Most of the gastrointestinal lesions consistent with Wegener's disease are usually found at necropsy. Clinical gastrointestinal manifestations are scarce and rarely due to the underlying disease. Prognosis depends upon the renal lesions. However, as well, involvement of the digestive tract seems to be a factor of poor evolution of the disease.

Biopsy↗
PubMed1984

[Cholesterol crystals and biliary lithiasis. Importance of the study of bile collected by duodenal intubation].

Cholesterol crystallization in a necessary step in the formation of cholesterol gallstones. Our purpose was to study the relationship between the presence of biliary cholesterol crystals and radiolucent gallstones. Bile was obtained by duodenal intubation from 60 subjects free of hepatic disease: 40 patients had radiolucent gallstones and in the remaining 20 subjects no gallstones could be found either by oral cholecystography or by ultrasound examination. In each patient a bile sample was used to search for cholesterol crystals; in another sample, biliary cholesterol, phospholipids and bile acids were measured to calculate the lithogenic index. Among the 44 subjects with lithogenic bile, 34 had radiolucent gallstones. Twenty-two out of the 60 patients had both cholesterol crystals and radiolucent gallstones; 21 subjects out of the 22 had lithogenic bile. In patients with frequent biliary colic or subacute pancreatitis without visible gallstones, finding cholesterol crystals in bile might suggest medical or surgical specific treatment.

Adult↗
PubMed1983

Two patients with pancreatic apudomas secreting neurotensin and VIP.

Two patients have been studied with a two and a half and nine year history of metastatic pancreatic apudoma. In both patients the main feature was chronic watery diarrhoea with remissions after partial tumour resection and streptozotocin therapy. Plasma levels of circulating VIP and neurotensin were persistently raised in both patients. Chromatographic analysis of the plasma showed that a significant proportion of the raised immunoreactivity of both peptides eluted in an identical position to pure VIP and neurotensin. The extremely high concentrations of neurotensin did not appear to result in any feature which would allow distinction from the classical VIPoma syndrome.

Adult↗
PubMed1978

"False positive" acidified serum test in a preleukemic dyserythropoiesis.

In a case of preleukemic dyserythropoiesis, in vitro red cell lysis tests showed a positive acidified serum test whose characteristics are described. The positive acidified serum test occurred in 10 normal sera, in 1 serum with complete deficiency of the fourth component of complement and in 1 serum with complete deficiency of the second component of complement. The test was found negative with 2 hyperlipemic sera. The other in vitro red-cell lysis tests were negative. The results of the in vitro lysis tests were different from the results obtained in paroxysmal nocturnal hemoglobinuria and congenital dyserythropoietic anemias.

Adult↗