Search PubMed⌕ Search

Biomedical subjects

G Dietrich

Publications and source records attributed to G Dietrich.

At least 91 records · Page 5Linked to original sources
PubMed1990

Primary hemostasis in hemodilution--2) Infusion solutions.

Various infusion solutions are used during preoperative hemodilution or for substituting intraoperative blood loss. We examined the influence of saline 0.9%, albumin 5%, dextran 6% gelatin 3.5% and hydroxyethyl starch 6% (HES, mw 40,000 and 450,000) on primary hemostasis using the In-vitro bleeding test (IVBT) on composed blood samples of different hematocrit but constant platelet concentration. All infusion solutions tested caused longer bleeding times, depending on the volume used. Saline and albumin had the strongest effect, whereas high molecular weight HES or dextran showed hardly any impairment, if used in a quantity of less than 20% of the blood volume. Autologous plasma seems to be the best substitute in hemodiluted patients, at least if more than 20% of the blood volume has to be substituted by infusion solutions.

Bleeding Time↗
PubMed1990

Normal immunoglobulin G (IgG) for therapeutic use (intravenous Ig) contain antiidiotypic specificities against an immunodominant, disease-associated, cross-reactive idiotype of human anti-thyroglobulin autoantibodies.

Pooled normal polyspecific IgG for therapeutic use (IVIg) contain anti-idiotypes against idiotypic determinants expressed by autoantibodies from patients with a variety of autoimmune diseases. In the present study, antiidiotypes in IVIg are shown to recognize a cross-reactive idiotype on human anti-thyroglobulin (TG) autoantibodies, that was defined by heterologous antiidiotypic antibodies, termed anti-T44 antibodies. The T44 idiotype is located outside the antibody-combining site of anti-TG autoantibodies. F(ab')2 fragments from anti-T44 antibodies inhibited the binding of IVIg to affinity-purified F(ab')2 anti-TG autoantibodies. Anti-T44 antibodies bound to F(ab')2 fragments of patients' antibodies, which were retained on an affinity column of Sepharose-bound F(ab')2 fragments from IVIg, but not to F(ab')2 fragments from the effluent of the column. The T44 idiotype was expressed on antibodies that bound to IVIg from eight of nine patients with autoimmune thyroiditis, but not on IVIg-binding Igs from healthy individuals. A small amount of the T44 idiotype was also expressed on the fraction of IVIg that bound to itself upon affinity chromatography. The T44 idiotype was cross-reactive between antibodies from patients with autoimmune thyroiditis. Thus, IVIg contain antiidiotypic antibodies directed against an immunodominant disease-associated cross-reactive alpha-idiotype of human anti-TG autoantibodies. These results support the concept that IVIg may be beneficial in selected autoimmune diseases by modulating the function of the idiotypic network.

Animals↗
PubMed1990

[Use of phospholipids (Fibraccel) for hemostasis in thrombocytopenic-thrombocytopathic patients].

Eight thrombocytopenic/pathic patients received an intravenous infusion of phospholipids. In-vitro-bleeding test, thrombelastography and resonance thrombography were performed in order to show the hemostatic effect. There was no case in which phospholipids had an efficacy comparable to the transfusion of platelets. Two patients suffered from a severe anaphylactoid reaction after the administration of phospholipids.

Adolescent↗
PubMed1989

In vitro bleeding test--a simple method for the detection of aspirin effects on platelet function.

We investigated platelet function of 21 healthy blood donors before, 4 hrs and 1 to 7 days after a single oral dose of 0.02 (n = 3), 0.05 (n = 3), 0.1 (n = 3), 0.5 (n = 2) and 1.0 g (n = 10) aspirin. Three additional donors received 0.02 g aspirin/day for 5 days. A new and simple in vitro bleeding test (Thrombostat) using whole blood was far more sensitive than all other tests for platelet function (subaquatic bleeding time, thrombelastrogram, resonance-thrombogram, platelet adherence, spreading and aggregation). With this method using 2mM CaCl2 as additional agent all donors showed significantly increased in vitro bleeding volumes, for at least 2 days after ingestion of 0.1 to 1 g aspirin. In the majority of cases the aspirin effect could be detected even after 5-6 days. In 2 of 3 donors even 0.05 g aspirin was detectable. There was already a definite effect seen after 2 days in all 3 cases when 0.02 g was ingested daily. The new in vitro bleeding test should be suitable for the control of low dose aspirin prophylaxis of arterial thromboembolic disorders.

Aspirin↗
PubMed1989

Antiidiotypic suppression of autoantibodies with normal polyspecific immunoglobulins.

A mechanism by which therapeutic normal polyspecific immunoglobulins (IVIg) may suppress autoimmune responses in vivo is that of antiidiotypic suppression of autoantibodies mediated by anti-idiotypes present in IVIg. In vitro incubation with IVIg of either the plasma or the IgG fraction from plasma of patients with autoantibodies against procoagulant factor VIII (VIII:C), DNA, thyroglobulin, peripheral nerve and intrinsic factor resulted in dose-dependent inhibition of autoantibody activity. The pattern of inhibition curves showed a prozone phenomenon. Maximal inhibition was achieved at a ratio of patient's IgG to IVIg which was specific for each antibody tested. Inhibition was dependent on idiotypic/antiidiotypic interactions between autoantibodies and IVIg since: 1) F(ab')2 from IVIg inhibited autoantibody activity in F(ab')2 fragments from patients' IgG; 2) IVIg contained no antigen-like activity and no antibodies against the commonest allotypes expressed in F(ab')2 fragments of human IgG; 3) autoantibody activity in F(ab')2 fragments from patients' IgG was specifically retained on affinity columns of Sepharose-bound F(ab')2 fragments from IVIg. The presence of antiidiotypes against autoantibodies in pooled normal IgG supports the concept of a functional idiotypic network regulating autoimmune responses in man.

Antibodies, Anti-Idiotypic↗
PubMed1989

Anti-idiotypes against autoantibodies in normal immunoglobulins: evidence for network regulation of human autoimmune responses.

This manuscript summarizes observations indicating that anti-idiotypes against human autoantibodies may be found in sera from patients recovered from autoimmune disease and in pooled normal polyspecific immunoglobulins (IVIg). The evidence that IVIg contain anti-idiotypes against autoantibodies includes: 1) inhibition by F(ab)2 from IVIg of the binding of F(ab)2 autoantibodies to their autoantigens; 2) specific retention of autoantibodies upon affinity chromatography of F(ab)2 fragments containing autoantibody activity on Sepharose-bound F(ab)2 from IVIg; 3) lack of detection of anti-allotypes and lack of significant anti-Fc activity in IVIg; 4) specific competitive displacement by polyclonal heterologous F(ab)2 anti-idiotypes of the binding of IVIg to affinity-purified F(ab)2 autoantibodies. The high number of donors contributing to IVIg endows the preparations with anti-idiotypic specificities that may not necessarily be detectable in plasma from single healthy individuals. Our observations of the presence in IVIg of anti-idiotypes against pathogenic autoantibodies and against IgG and IgM autoantibodies found in low amounts in normal sera supports the concept of a functional network regulating expression of autoimmunity in humans. We suggest that IVIg may be efficient in selected autoimmune diseases by providing a source of anti-idiotypes with a wide range of specificities brought as interconnected antibody species that may conpensate for altered connectivity of the immune network of patients with autoimmune diseases.

Autoantibodies↗
PubMed1983

[B-scan sonography of the carotid artery].

176 sonograms of carotid arteries are compared with the corresponding angiograms to evaluate the diagnostic possibilities of B-mode sonography in detecting arteriosclerotic vessel disease. Ultrasound tomography is proved to be a reliable method to rule out arteriosclerosis; the specificity of the investigation method is 100%. However, the diagnostic value varies concerning the visualization of different arteriosclerotic lesions. B-mode sonography is of minor significance in detecting arteriosclerotic ulcers. Fresh thrombi are often not diagnosed. The sensitivity of this investigation method therefore corresponds 85%.

Angiography↗
PubMed1980

[Proof of the jejunogastric bile reflux after BII partial gastrectomy using 99mTc diethyl-IDA (author's transl)].

A history was obtained and barium meal and gastroscopy performed on 42 patients after a Billroth II partial gastrectomy. In order to demonstrate and quantify jejuno-gastric bile reflux, hepato-biliary sequential scintigraphy was carried out using 99mTc diethyl-IDA. The method has advantages over conventional techniques in that it is easy for the patient and demonstrates reflux both when the stomach is empty and full. The result showed that all patients who had evidence of inflammatory changes or ulcers on barium meal or gastroscopy had evidence of reflux.

Adult↗
PubMed1980

[Contrast amplification of the liver parenchyma in the computer tomogram by using intravenous and peroral biliary contrast media (author's transl)].

If intravenous, biliary contrast media are used, a slight albeit specific enhancement of contrast of the liver parenchyma occurs with the applied dosage, which can be utilised in individual cases, for example for identifying isodense lesions. Contrast amplification by the peroral cholegraphic agent under examination, is insufficient for use in computer tomography of the liver. The use of biliary contrast media usually enables very good visualisation of the extrahepatic bile ducts. Attention is drawn to the possibility of pharmakokinetic studies by means of computer tomography.

Administration, Oral↗
PubMed1979

[Endoscopic sphincterotomy and removal of a gallstone from the common bile duct (author's transl)].

Twenty-one patients with an average age of 69 years were subjected to endoscopic sphincterotomy of the papilla of Vater over the past six months. This therapeutic approach was successful and without ensuring complications in 20 of these patients. Hence, endoscopic sphincterotomy can be recommended in the case of elderly or high-risk patients as an alternative form of therapy to surgery with the attendent dangers of anaesthesia and, in particular, duodenotomy. However, it is unlikely to become a routine procedure since a team of highly-experienced specialists in endoscopy is mandatory with the close cooperation of radiologists and surgeons. The technique, indications and complications are mentioned.

Age Factors↗
PubMed1978

Teaching psychiatric nursing in the classroom.

The practice in teaching psychiatric nursing to post registration student nurses at the Bethlem Royal & The Maudsley Hospital School of Nursing is described, showing the exclusive use of experiential teaching methods. Five distinct courses are conducted at present in this topic: 1 discussions based on written work; 2 discussions centring on set topics; 3 group dynamics discussions and projects; 4 psychodrama exercises; 5 supervision classes. The latter are conducted in a manner not previously described. The dependence of effective classroom teaching on the students' ward experience is demonstrated.

Group Processes↗