PubMed Health⌕ Search

Biomedical subjects

M Steinbuch

Publications and source records attributed to M Steinbuch.

At least 19 recordsLinked to original sources
PubMed1990

Inhibition of activated protein C by aprotinin and the use of the insolubilized inhibitor for its purification.

The study of the interaction between activated protein C (APC) and non-plasmatic inhibitors allowed us to demonstrate that aprotinin is a potent competitive inhibitor of APC with a Ki of 1.35 mumol/L. It was possible to adsorb immunopurified protein C (PC) activated by venom activator to insolubilized aprotinin and to recover the active enzyme after elution by HCl 0.1 N or by a chaotropic ion, for example KSCN 3 mol/L. The interaction involved the active-site of the enzyme since PC and DIP-APC did not bind to the matrix. Thus, APC could be purified, after activation, in a one-stage procedure out of a mixture of protein such as a prothrombin complex concentrate.

Amides↗
PubMed1989

A human factor VIIa concentrate and its effects in the hemophilic A dog.

Properties of a new concentrate of FVII/FVIIa, obtained by adsorption onto an inorganic adsorbent followed by a chromatographic step onto Q-Sepharose using a by-product of routine fractionation as starting material, are described. This fraction contains only small amounts of the other components of the prothrombin complex but it is enriched in Proteins C and S. This preparation is essentially free of FVIIICag. It has been submitted to animal experiments including those carried out on normal and hemophilic A dogs. A normalization of the buccal bleeding time was seen after injection of a minimal dose of 4 uFVIIa/kg. No adverse reaction was observed at any dose employed. This concentrate might thus be indicated for the treatment of Haemophilia A patients with inhibitors. Its viral inactivation has been achieved.

Animals↗
PubMed1979

[Purification and concentration of albumin solutions by diafiltration using a parallel membrane dialyzer].

The last two years, artificial Kidneys have been used for purification and concentration of human serum albumin solutions coming from plasma cracking in two Blood Transfusion Centers. Results are easily reproducible and the apparatus is reliable and of low cost. The properties of dialysis and ultrafiltration of the A.N. 69 membrane are useful for eliminating ethanol and water. The artificial Kidneys are effective at low pressure. It is then possible to use peristaltic pumps and to have a closed circuit. The whole apparatus must be sterilized with chemical reagents.

Dialysis↗
PubMed1979

Isolation of human C1q as a by-product of routine fractionation.

Clq can be isolated as a by-product of large scale fractionation. The euglobulins of fraction III are submitted to chromatography on CM-cellulose in a batch-procedure. The active fraction being frequently contaminated by lysozyme the protein can be further purified by gel-filtration in the presence of carbohydrates. The purified Clq is suitable for the detection of immune complexes.

Chemical Fractionation↗
PubMed1979

Side products of routine plasma fractionation. I. Serum cholinesterase (EC 3.1.1.8).

Cholinesterase (EC 3.1.1.8) for intravenous use has been obtained from fraction IV, a by-product of ehtanol fractionation. A four-step procedure has been developed associating precipitation by Rivanol and PEG 4000 with chromatography on DEAE-cellulose. The yield corresponds to 30--35% of the activity found in fraction IV. Vials containing 5000 U of CHE stabilized by 2.5% albumin have been prepared. The pyrogen-free product is well tolerated in the human.

Centrifugation↗
PubMed1977

[Properties of and information about a new preparation of immunoglobulins (IgGAM) enriched in IgA and IgM].

A new immunoglobulin preparation, called IgGAM, has been obtained from fraction III. Fraction III obtained during large scale fractionation is used as starting material and caprylic acid for the precipitation of most proteins other than the immunoglobulins present in fraction III; the immunoglobulin concentrate is finally obtained by ethanol precipitation of the supernatant. The IgGAM preparation contains IgG,IgA and IgM in various proportions according to the modifications of the initial technique, and we can obtain fractions more specially enriched in IgA or in IgM. The clinical results obtained with IgGAM preparation are summarized; different types of antibody deficiency syndromes have been successfully treated. It can be injected once à week IM, at a dose of 0.5 ml/kg. No side effects, nor appearance of anti IgA antibodies have been observed.

Female↗
PubMed1977

Distribution of IgG subclasses in commercial and some experimental gamma-globulin preparations.

The IgG subclass distribution was determined in six commercial and in four experimental human gamma-globulin preparations. The concentrations of IgG subclasses were measured in a modified radiommunoassay using subclass-specific antisera. In commercial gamma-globulins, the distribution of the subclasses corresponded roughly to the distribution in normal human serum. A considerable enrichment of the IgG 4 was found in experimental lots prepared either from the ethanol fraction III or from the rivanol-precipitable IgG.

Blood Specimen Collection↗
PubMed1977

[Proteolytic breakdown of human inter-alpha-trypsin inhibitor by plasmin (author's transl)].

Inter-alpha-trypsin inhibitor was isolated from human plasma and submitted to proteolytic degradation by plasmin. A split product of low molecular weight (18 000 daltons) is obtained by gel filtration or solubilisation in perchloric acid. This fragment reacts with an anti-inter-alpha-trypsin inhibitor immune serum and migrates as beta1 globulins. Its specific activity against trypsin (after absorption of residual plasmin on sepharose lysine) was estimated to be 900 mU1/mg. Thus one molecule of fragment can inhibit one molecule of trypsin. As well with native protein as with its fragment, complexes formed with trypsin can be dissociated by urea or sodium dodecyl sulfate. This fragment is similar to the small molecular weight inhibitors obtained directly by solubilisation in perchloric acid from serum, urine and bronchial secretions.

Antigens↗
PubMed1976

Ceruloplasmin-anion interaction. A circular dichroism spectroscopic study.

The effect of anion binding to ceruloplasmin has been studied using absorption and cirbular dichroism spectral data. At anion to ceruloplasmin molar ratios approaching infinite, OCN-, N3- and SCN- bind to ceruloplasmin giving rise to similar alterations in circular dichroism and absorption spectra. The positive bands at 610 and 520 nm in circular dichroism spectra disappear, a negative one apperars at 600 nm and the peak at 450 nm is only slightly modified. There is a new negative band at 410 nm well-defined in OCN- ceruloplasmin spectra. The decrease in absorption at 610 nm is ascribed to the disruption of one type I Cu-S(cysteine) bond owing presumably to the changes induced by anions in the protein secondary structure. The new band at 410 nm is assigned to a charge transfer transition from the ligand replacing cysteine at its binding site. Both absorption and circular dichroism spectra show isobestic points indicating that anion binding to the enzyme, disruption of one of the two type I Cu-S bonds and coordination of this Cu to another protein residue take place simultaneously.

Anions↗
PubMed1976

[The use of new immunoglobulin preparation, enriched in IgA and IgM (IgGAM)].

The clinical results obtained with fraction IgGAM are reported. Different types of antibody deficiency syndromes have successfully been treated : 8 cases of Bruton-type agammaglobulinemia. In one of these case a tenacious Pseudomonas infection cleared off during the treatment. Two cases of non sex-linked familial agammaglobulinemia. Three cases of isolated IgM deficiency. Five cases of isolated IgA deficiency. Five cases with Soothill type IgA deficiency associated with high IgE levels. Five cases of septicemia of the new-born. Three cases with acquired agammaglobulinemia and in the premature infant (5 cases). No side-effects nor appearance of anti-IgA antibodies have been observed.

Adult↗
PubMed1976

[Substitutive treatment of hemopjolia A using a new factor VIII concentrate].

Thirty children with classical hemophilia were treated with an intermediate-purity factor VIII concentrate prepared according to Newman. The average factor VIII concentration was 21 U/ml. Thirty five injections ranging from 3 to 55 U/kg of body weight were given. The clinical efficacy was satisfactory, no side effects were observed. In vivo factor VIII recovery was initially very high, decreased rapidly until the 4th hour post infusion and then slowed according to a biological half-life of 11.3 +/- 3.1 hours. A satisfactory correlation between the dose injected and the factor VIII in vivo recovery was observed only after four hours post injection. The commercially available concentrate contains in average 25 U of factor VIII per ml, 13 U/mg of fibrinogen and 2.03 U/mg of proteins. It can be injected with a seringe and is therefore adapted to home care treatment. In addition, it is convenient for prolonged treatment with high doses of factor VIII as required by surgical procedure of treatment of patients with an inhibitor, avoiding limitations caused by hypervolemia or hyperfibrinogenemia.

Adolescent↗