Biomedical subjects

R Eckstein

Publications and source records attributed to R Eckstein.

At least 19 recordsLinked to original sources

PubMed1992

Bone marrow processing with the Fresenius AS 104: initial results.

Prior to purging, cryopreservation, or ABO-incompatible bone marrow (BM) transplantation, we have concentrated 23 BM harvests using a modification of the "grancollect-protocol" and the recently available bone marrow stem cell (BMSC) protocol of the Fresenius AS 104 cell separator with the P1-Y set. Within 40-70 minutes, the initial marrow volume of 922 ml (+/- 408 ml) was processed two to three times. A mean of 59% (+/- 20%) of the initial mononuclear cells was recovered in a mean volume of 119 ml (+/- 31 ml). The recovery of clonogenic cells, measured by CFU-GM assays, was 98% (+/- 80%). Red blood cells in the BM concentrates were reduced to 8% (+/- 4%) of the initial number. The procedure was efficient and yielded a BM cell fraction suitable for purging, cryopreservation, and transplantation. All transplanted patients showed fast and sustained engraftments after autologous or allogeneic BM transplantation.

Bone Marrow Cells↗

PubMed1992

Microfollicular thyroid adenoma and congenital goitrous hypothyroidism.

Three patients with congenital goitrous hypothyroidism are reported. They were treated with adequate thyroxine replacement and developed well defined microfollicular thyroid adenomas despite being euthyroid clinically and biochemically throughout their clinical course. Patients with congenital goitrous hypothyroidism appear to be at increased risk of developing thyroid adenoma in childhood despite the use of replacement thyroxine treatment in physiological doses.

Adenoma↗

PubMed1992

Effective derosetting of mononuclear cells isolated by immunomagnetic beads.

A rapid and effective method for the derosetting of peripheral mononuclear cells (PMNC) isolated by CD8 monoclonal antibody (MoAb) coated immunomagnetic beads (IMB) is described. PMNC are positively selected and enriched by CD8-IMB and then derosetted from the IMB by a polyclonal antibody (PoAb) preparation against mouse Fab. Our experiments confirm the feasibility of this method with a high derosetting efficiency.

Antibodies, Monoclonal↗

PubMed1992

Bone marrow purging prior to autologous transplantation.

Our data suggest that ex vivo bone marrow purging using monoclonal antibodies (MoAbs) and sheep-anti-mouse immunobeads (SAM beads) prior to autologous bone marrow transplantation (ABMT) allows satisfactory tumor cell reduction without critical stem cell losses. Nevertheless, there is only a reduction but no elimination of tumor cells. The consequences will have to be clinically discussed.

Antibodies, Monoclonal↗

PubMed1992

[Effect of leukocyte depleting polyester filters on thrombocytapheresis concentrates].

We studied platelet loss, leukocyte depletion, T/B cell ratio, platelet morphology and platelet function (aggregation, hypotonic shock reaction, retention and retraction) prior to and after filtration through two different polyester filters (Sepacell PL-5A, Pall PL100) as well as the posttransfusional platelet increment 1 h after transfusion in 8 pairs of single-donor platelet concentrates (Cobe Spectra, Fresenius AS 104). Leukocyte depletion was effective (>99.9%) and platelet loss acceptable in both filters, all tests showing no indication of a diminished platelet function by filtration.

Blood Component Transfusion↗

PubMed1992

[Autologous blood donation and erythropoiesis].

Autologous blood donation before elective surgery has been widely endorsed as good transfusion practice. Although only 6% of patients undergoing elective orthopedic surgery are unable to donate 3 autologous units, 40% cannot donate 4 units because they become anemic. According to the results of our study this must be due to different problems of bone marrow dynamics, which cannot be overcome by unselected use of human recombinant erythropoietin.

Adult↗

PubMed1992

[Hemoglobin follow-up of orthopedic autologous blood transfusion patients].

Patients undergoing autologous donation prior to elective orthopedic surgery show better Hb values during the perioperative period compared to those without autologous donation, all patients in both groups receiving no homologous transfusion. The widely assumed improvement of Hb regeneration during the postoperative period according to an erythropoiesis stimulated by preoperative autologous donation is not supported by our data.

Adult↗

PubMed1992

[Attempts in developing a standardized test system of immunologic reactivity].

Stimulation of lymphocytes with mitogens and antigens is an established model for in vitro testing of immunoreactivity. Due to the great variability of blastogenic response the interpretation of these results is difficult. Our results suggest that multivariate experiments and statistics improve the interpretation.

Antigens, Bacterial↗

PubMed1992

[Strong and weak histocompatibility antigens and immune response].

In blood samples of 88 healthy donors various red cell, HLA-A, -B, -Cw and -Dr antigens were determined by standard methods. Lymphocyte reactivity was measured by 3H-thymidine uptake into DNA of lymphoblastic cells stimulated by 14 different mitogens and antigens. Cluster analysis confirmed by t test and F test defined 3 distinct clusters of lymphocyte reactivity. Cluster 1 in 70% [relative risk (r.r.) 109, p < 0.001] and cluster 3 in 92% (r.r. 33, p < 0.01) showed significantly different cumulations of 3 or more increased characteristic red cell and HLA antigens. Our data suggest that the patterns of both red cell and HLA antigens play a major role in defining immunoreactivity.

HLA Antigens↗

PubMed1992

[Acquired autoimmune hemolytic anemia after liver transplantation by "auto"-anti-A and "auto"-anti-P1].

A 47-year-old man (group A) received a cadaver liver from a group 0 donor. On day 8 after the transplant the recipient developed severe immune hemolysis and showed a positive direct antiglobulin test due to two antibodies (anti-A and anti-P1) of transplant donor origin. The possible mechanisms involved in "autoantibody" formation in the recipient are discussed.

ABO Blood-Group System↗

PubMed1992

[Examination of a Berlin blood donation branch for antibodies to hepatitis C virus with the anti-HCV test and for circulating HCV-RNA using polymerase chain reaction].

Hepatitis C virus (HCV) is responsible for the majority of cases of transfusion-related hepatitis. We performed a first-generation anti-HCV EIA in 665 repeat and 168 first-time blood donors from Berlin. 4.7 and 4.2%, respectively, showed at least one indeterminate or positive result. We further looked for HCV genome in the plasma of 20 donors with reactive anti-HCV-EIA doing a polymerase chain reaction (nested PCR). The control group consisted of 20 patients with chronic hepatitis C. The PCR was negative in all examined blood donors, but was positive in 17 of 20 controls. These findings raise the question, if a positive anti-HCV test correlates with infectiosity.

Berlin↗

PubMed1992

[Anti-M after transfusion as an indication of a genetic variant of the MN locus].

We report a case of an anti-M antibody (titer 128) and MN red blood cells (RBC) in a 76-year-old female German patient. In our case, however, RBC showed weak reactions to human anti-M compared with strong reactions using rabbit anti-M. Papain treatment destroyed the RBC reactivity to human anti-M whereas the strong reactivity to rabbit anti-M was unchanged. This pattern was also demonstrable in the patient's son and grandson. Our results indicate the existence of a rare allele at the MN locus in this family.

Aged↗

PubMed1992

[Follow-up of blood donors with indeterminate reaction to anti-HIV 1/2 EIA or isolated detection of antibodies to HIV-1 core antigens (anti-p24)].

Over a period of 20 months we identified 10 voluntary blood donors with indeterminate reactions in anti-HIV 1/2 EIA tests. Western blot (WB) patterns of 6 of these 10 donors showed isolated core antibodies (anti-p24), in 4 cases WB patterns were negative. After a median follow-up period of 58 weeks (range 12-93) we have not seen a case of typical seroconversion.

AIDS Serodiagnosis↗

PubMed1992

[Changes in thrombocytapheresis concentrations caused by leukocyte depletion with polyester filters].

We studied platelet loss, leukocyte depletion, T/B-cell-ratio, platelet morphology and platelet function (aggregation, hypotonic shock reaction, retention and retraction) prior to and after filtration through two different polyester filters (Sepacell PL-5A, Pall PL100) as well as the posttransfusional platelet increment 1 h after transfusion in 8 pairs of single donor platelet concentrates (Cobe Spectra, Fresenius AS 104). Leukocyte depletion was effective (greater than 99.9%) and platelet loss acceptable in both filters, all tests showing no indication of a diminished platelet function by filtration.

Hemofiltration↗

PubMed1992

[Erythropoiesis and iron metabolism in autologous blood donation].

Autologous blood donation before elective surgery has been widely endorsed as good transfusion practice. Although only 6 percent of patients undergoing elective orthopedic surgery are unable to donate 3 autologous units, 40 percent cannot donate 4 units because they become anemic [1,2]. According to the results of our study this must be due to different problems in bone marrow dynamics, which cannot be overcome by unselected use of human recombinant erythropoietin alone [3].

Adult↗

PubMed1991

Cellular immunity in schizophrenic patients before and during neuroleptic treatment.

A possible connection between immunological alterations and schizophrenia has been discussed for many years. We studied 55 schizophrenic patients in an acute stage of illness before they began neuroleptic treatment. 35 patients who showed clinical improvement on neuroleptics, and 51 healthy controls. Our interest was focused on parameters of cellular immunity. We found an increased lymphocyte response to stimulation with pokeweed mitogen (PWM) and phytohemagglutinin (PHA) in patients before neuroleptic therapy and also an increased response to stimulation with PWM and PHA during treatment compared to controls. Stimulation with antigens generally showed a lower lymphocyte response in patients than in controls, but the difference was only significant after stimulation with tuberculin before neuroleptic treatment and after stimulation with varidase, diphteria-toxoid, tuberculin, vaccinia, and rubella during neuroleptic treatment. The number of CD3+ and CD4+ cells, but not the number of CD8+ cells, was increased before and during treatment in comparison to controls. Suppressor-cell activity was reduced in three different suppressor cell assays before and during neuroleptic medication compared to controls. We therefore conclude that alterations of the immunological system which are, as has been demonstrated, not due to treatment with neuroleptics might play a role in schizophrenia.

Adolescent↗

PubMed1991

[Stem cell separation with different cell separators].

For some years, there has been an increasing success in transplanting peripheral blood stem cells (PBSC) instead of autologous bone marrow in patients suffering from different malignancies. While collecting PBSC for autologous transplantation, we compared four different separation techniques and three different cell separators (COBE Spectra, Fresenius AS 104, Haemonetics V50) routinely used for platelet production. Our results suggest that continuous flow separators seem to have some advantage over discontinuous flow machines in harvesting PBSC.

Blood Cell Count↗

PubMed1991

[Clinical use of peripheral stem cells for autologous transplantation].

Peripheral blood derived hematopoietic stem cells (PBSC) have been transplanted successfully to eight patients suffering from different malignancies. The separations were started during chemotherapy-induced cytopenia and large volumes of peripheral blood were processed. Using this separation concept, it was possible in all cases to obtain the stem cell amount necessary for hematopoietic reconstitution.

Blood Cell Count↗