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W Mempel

Publications and source records attributed to W Mempel.

At least 37 records · Page 2Linked to original sources
PubMed1993

Cellular immunity, HLA-class I antigens, and family history of psychiatric disorder in endogenous psychoses.

We found an increased lymphocyte proliferation after stimulation with an antigen "cocktail" in 49 schizophrenic patients and 37 patients suffering from affective psychosis, compared with 45 healthy control subjects. On the basis of this and other findings such as increased numbers of CD3+ and CD4+ cells, an increased ratio of CD4+/CD8+ cells, and a reduced level of suppressor cell activity in schizophrenia and endogenous depression, we investigated the influence of the human leukocyte antigen-Class I (HLA-A, HLA-B, HLA-C) system on the altered immune function and evaluated the relationship to immune function of a family history of psychiatric disorders. A cluster analysis of cases with regard to the HLA-Class I antigens was first performed in a group of 133 healthy control subjects, and two immunogenetically different clusters were found; then 86 patients (49 schizophrenics, 37 affective psychoses) for whom immune functional data were available were assigned to the two HLA-I clusters that had been determined in the control subjects. Analyses of variance (ANOVAs) showed no differences in immune function between the two clusters. With respect to the cluster assignment and the family history of psychiatric diseases, a two-way ANOVA revealed significant differences in the lymphocyte response to the antigen cocktail, in the number of CD8+ cells, and in one suppressor cell assay. When patients were compared by ANOVA on the basis of family history of psychiatric disorder, patients with a positive family history showed a significantly higher number of CD4+ cells and a higher CD4+/CD8+ ratio. Moreover, certain HLA genes, especially HLA-A1, HLA-B8, HLA-B16, and HLA-C2 seemed to be related to the immune function and/or to the immune function and the family history.

Adolescent↗
PubMed1993

Investigations of the cellular immunity during depression and the free interval: evidence for an immune activation in affective psychosis.

1. Results of investigations of the immune function in affective disorders are conflicting. Some authors described an immune suppression, others an immune activation in major depression. The authors performed a study of cellular immunity in the MDD subtype endogenous depression. 23 patients suffering from endogenous depression were investigated during the depressive state, the results were compared with a group of 14 patients during the free interval and 51 healthy controls. 2. The lymphocyte proliferation after incubation with diphtheria- and tetanus toxoid, mainly stimulating T-cells, was reduced but after incubation with an antigen-cocktail, stimulating both, T- and B-cells, was increased in patients during depression and during the free interval compared to controls. 3. The CD3(+)- and CD4(+)-cells were significantly enhanced in both groups of patients while the CD8(+)-cells showed no differences to the controls. The ratio CD4+/CD8+ was increased in patients, too, as described in some autoimmune disorders. 4. The suppressor cell activity was significantly reduced in the PWM-assay and in the PHA-assay. The mixed lymphocyte culture showed a tendency to reduced suppressor cell activity as well. 5. The results point to an immune activation and to a disturbed control of the proliferative activity in affective psychosis. A T-cell related defect, not compensated by an increased number of CD3+- and CD4+ -cells is discussed. 6. From our point of view, the conflicting results of psychoneuroimmunological investigations in depressive disorders may be related to etiologically different subgroups of depression. The diagnostic category of MDD is possibly one of the traps in psychoneuroimmunology.

Adult↗
PubMed1993

Storage of single-donor platelet concentrates: metabolic and functional changes.

During the last decade, the trend toward intensifying chemotherapeutic regimens in patients with hematologic malignancies rapidly increased the demand for single-donor platelet concentrates (PCs). The logistics of such supply, however, necessitated the storage of these blood components prior to transfusion. Today, most blood centers use di(2-ethylhexyl)phthalate-free blood bags, which are assumed to allow a storage period of up to 5 days. This report describes biochemical and functional changes of stored single-donor PCs, which may influence the expected quality of PCs. The acid-base status is characterized by an initial respiratory alkalosis compensated by a metabolic acidosis. Changes in extracellular electrolyte, lactate dehydrogenase, glucose, lactate, elastase, and complement levels, as well as in the release of alpha granule content and the initial activation of plasma coagulation, are demonstrated. These changes result in a functional impairment of stored PCs as reflected by thromboxane and serotonin release reaction and by aggregation and in vitro bleeding time studies. In contrast, in vivo recovery and survival rates have been reported to be unaffected. Whether the good recovery and survival rates are caused by a rejuvenescence of stored PCs in vivo or are due to injured circulating platelets has not yet been proven.

Adenosine Diphosphate↗
PubMed1993

Effects of recombinant human erythropoietin on autologous blood donation before open heart surgery.

We studied the effects of four different doses of recombinant human erythropoietin (rhEPO) on the amount of preoperative autologous blood donation. 43 patients prior to open heart surgery were randomized into 5 groups (100, 200, 400, 800 U/kg rhEPO i.v. or placebo) and treated twice weekly over a period of 4 weeks. Autologous blood was taken at a hemoglobin of 13 g/dl and a hematocrit of 34% respectively. Application of low-dose rhEPO (100 and 200 U/kg) did not increase the amount of autologous blood donated, only 400 and 800 U/kg produced a significant increase by 27% and 39% respectively (p < 0.01) In addition RBC showed a reduced decline of hemoglobin level (p < 0.01). Reticulocytes increased by 2.5 times the baseline in the placebo and treatment groups up to 200 U/kg. Again, only 400 and 800 U/kg produced a significantly higher increase of 3.2 and 3.6 times respectively (p < 0.05 and p < 0.01). Although iron was supplied orally, ferritin levels declined in all groups whereas serum iron and transferrin levels remained unchanged. No influence could be detected on WBC, thrombocyte count, or arterial blood pressure. Mild and reversible side effects were observed in 8 patients (19%). Perioperatively 34 patients (81%) received exclusively autologous blood, only 8 patients (19%) needed additional homologous blood transfusions. Administration of high-dosed rhEPO (400-800 U/kg) seems to be an effective treatment with only slight side effects for increasing erythropoiesis during autologous blood donation.

Adolescent↗
PubMed1993

[Substitution of thrombocyte concentrates in polytransfused patients].

The routine use of platelet concentrates has greatly increased during the last years. Most of the concentrates are transfused to hematologic patients, who frequently receive additional red blood cells. These polytransfusion regimens often result in the formation of HLA- or platelet-specific antibodies, which lead to refractoriness to further platelet support. In order to avoid this problem, the number of HLA antigens transmitted should be reduced. Therefore, a consequent leukocyte depletion of all blood products administered to multitransfused patients seems to be necessary. If antibodies are already preformed in the patient's serum, compatible platelets have to be selected for transfusion.

Animals↗
PubMed1993

[Current focus: blood transfusion. Risks and problems in blood transfusion].

Blood transfusion became the subject of major interest because of a possible HIV-infection. It should not been forgotten, however, that HIV-infection is not the only of a wide variety of risks. The leading complication is still the hemolytic transfusion reaction, followed by transmission of hepatitis or other viral or bacterial germs. Less striking side effects, like an immunomodulation or a graft-versus-host reaction, should also been included into the therapeutical considerations. One possibility to avoid risks, is the use of autologous blood. The most important requirement, however, remains to operate with a minimal blood loss.

Blood Donors↗
PubMed1993

[Clinical effects of blood transfusion-associated immune modulation on outcome of tumor surgery].

Extended experimental studies revealed different immunological mechanisms which are possibly responsible for blood transfusion-associated immunosuppressive conditions. To expect a clinical impact of these mechanisms on the course of tumor disease, it is necessary to postulate (1) that immunological mechanisms have a significant role in controlling tumor growth and (2) that blood transfusion-induced immunmodulation is long lasting. Both postulates are supported by recent reports and are the rationales of clinical studies indicating that blood transfusion is a risk factor for postoperative infections and tumor recurrence. Since all studies have been retrospective or uncontrolled, we performed a prospective controlled study in randomized groups of patients suffering from colorectal cancer and compared the effects of allogeneic and autologous blood transfusions. The results indicate that patients treated with allogeneic blood transfusion had significantly higher rates of postoperative infectious complications than patients who received autologous blood. Our preliminary follow-up observations found a trend towards higher tumor-free survival in patients treated with autologous blood which is statistically significant in subgroup analysis.

Adult↗
PubMed1993

[Storage of thrombocyte concentrates: quality control by in vitro bleeding test].

BACKGROUND: The increasing demand for single-donor platelet concentrates necessitates the storage of these blood products prior to transfusion. Quality control of these platelets, however, is still a problem. Most of the available techniques are time-consuming and require sophisticated equipment and specifically trained personnel. The present paper describes a new method for quality control of stored platelet concentrates. MATERIALS AND METHODS: Single-donor platelet concentrates were stored for 7 days; daily aliquots were taken and the in vitro bleeding time (Thrombostat 4000) and platelet aggregation (aggregometer) were determined. RESULTS: The in vitro bleeding test can be handled simply and fast. The results are comparable with those of platelet aggregation tests. CONCLUSION: The in vitro bleeding test provides a good alternative to the conventional methods commonly used for quality control of platelet concentrates.

Bleeding Time↗
PubMed1992

Complement activation during storage of blood under normal blood bank conditions. Effects of proteinase inhibitors and leukocyte depletion.

During storage of CPD-A1 preserved whole blood factors of the complement cascade become activated, as evidenced by a rapid increase in the concentrations of C3a-desArg and C4a-desArg. After 10 to 14 days of whole blood storage, the elevations of C3a and C4a levels were highly significant. This increase was paralleled by an increase in the concentration of the lysosomal proteinase elastase from polymorphonuclear (PMN) granulocytes. By contrast, the concentration of the C3 activator complex C4b2b remained unchanged even after 3 weeks of storage. The supplementation of the anticoagulant CPD-A1 with the polyvalent-proteinase-inhibitor aprotinin and the specific elastase-inhibitor eglin C failed to inhibit complement activation, whereas leukocyte depletion could partially abolish the increase of the concentration of C4a, but had no effect on C3a concentrations. These observations support the notion that cleavage of C4 during storage of whole blood is partially leukocyte dependent, whereas the activation of C3 is possibly caused by the activation of the alternate pathway of the complement system by contact of plasma with plastic surfaces.

Aprotinin↗
PubMed1992

Diagnosis of transfusion-associated graft-versus-host disease by genetic fingerprinting and polymerase chain reaction.

A patient with Hodgkin's disease (clinical stage IIIB) received chemotherapy and total nodal irradiation. After the transfusion of filtered packed red cells, this patient developed transfusion-associated graft-versus-host disease (TA-GVHD). The genetic fingerprint of the patient's peripheral blood lymphocytes (PBLs) differed completely from that of her other body tissues. Normally, after transfusion, only the patient's own genetic fingerprints are observed in the PBLs, as exemplified in more than 10 control cases in which the transfused blood had not been filtered before transfusion. No signal bands corresponding to those of the blood donor could be demonstrated in samples of the patient's tissue DNA. Moreover, chimerism was detected in the hybridization pattern of the patient's PBLs on the ninth day after the onset of symptoms. Polymorphic simple repeats in the HLA-DRB gene after amplification by polymerase chain reaction were also investigated, which confirmed the fingerprinting results. The advantages of these methods for the diagnosis of TA-GVHD include the rapid and unequivocal diagnosis as well as the fact that there is no need for the relatives to be HLA typed.

Adult↗
PubMed1992

Intravenous anti-D gammaglobulin for the prevention of rhesus isoimmunization caused by platelet transfusions in patients with malignant diseases.

Previous studies of sensitization to RhD by RhD-positive platelet transfusions in RhD-negative cancer patients have shown different frequencies of alloimmunization (max. 19%). We studied 37 RhD-negative patients who received RhD-incompatible platelet transfusions and simultaneously anti-D-immune globulin. We provide evidence that in this setting RhD-prophylaxis is highly effective in preventing alloimmunization due to RhD antigen, since none of the patients studied developed anti-D. Detection of other red blood cell antibodies than anti-D proves the possibility of immunization in these patients. Prevention of isoimmunization in patients with malignant diseases is recommended especially in young females, since an increasing number of patients are having successful pregnancies, despite prior or even during cytotoxic therapy.

Adult↗
PubMed1992

Effects of leukocyte depletion on the formation of anaphylatoxins in stored whole blood.

As reported earlier, factors of the complement cascade get activated in CPD-A1-stabilized whole blood. As early as after 10 days of storage under normal blood bank conditions the elevations of the concentrations of C3a-desArg and C4a-des-Arg were highly significant. By contrast, the concentration of the C3 activator complex C4b2b remained unchanged even after 3 weeks of storage. Leukocyte depletion partially inhibited the activation of C4 but had no effect on C3a concentrations. Therefore, cleavage of C4 during storage of whole blood seems to be partially leukocyte-dependent, whereas the activation of C3 is possibly due to the activation of the alternate pathway of the complement system by contact of blood to plastic surfaces. Even through the radioimmunologically measured C3a might be inactive as an anaphylatoxin, these observations are of clinical importance since the inactivated C3a-desArg still possesses biological activities such as activation of platelets which may lead to hypercoagulability and thrombosis.

Blood Preservation↗
PubMed1992

[Graft versus host disease with fatal outcome after administration of filtered erythrocyte concentrates].

Transfusion-associated graft-versus-host disease (TA-GVHD) resulting from the engraftment of competent lymphocytes contained in blood products has been well described in immunocompromised patients and more recently in immunocompetent patients. Prophylactic irradiation of blood products prior to transfusion is the most efficient way to prevent TA-GVHD. Standard blood bank measures to reduce mononuclear cell contamination in red blood cell units, such as freezing, washing and filtration, may reduce the number of viable lymphocytes to prevent immunizations. However, it is unknown whether the depletion of leukocytes with these techniques would decrease the risk of TA-GVHD. In this report we describe the first case of TA-GVHD following transfusion of filtrated red blood cells given to a patient receiving cytotoxic therapy for Hodgkin's disease.

Adult↗
PubMed1992

Decreased formation of the complement component C4A in leukocyte-depleted stored whole blood.

As reported earlier, factors of the complement cascade get activated in CPD-A1-stabilized whole blood. While leukocyte depletion inhibited partially the activation of C4, it had no effect on C3a concentrations. Therefore cleavage of C4 during storage of whole blood seems to be partially leukocyte-dependent, whereas the activation of C3 is possibly due to the activation of the alternate pathway of the complement system by contact of blood to plastic surfaces. Even though the radioimmunologically measured C3a might be inactive as an anaphylatoxin, these observations are of clinical importance since the inactivated C3a-desArg still possesses biological activities, like activation of platelets which may lead to hypercoagulability and thrombosis.

Blood Preservation↗
PubMed1992

[Combination of a simple hollow fiber system with leukocyte filter for production of leukocyte depleted erythrocyte concentrates and plasma].

Leukocyte-depleted red cell concentrate (RCC) and plasma were separated by a hollow fiber filter system combined with a leukocyte filter without any additional devices. The RCC with 100 ml additive solution had a weight of 329 g; hematocrit was 0.55, free hemoglobin 16 mg/dl; leukocytes were (0.6 +/- 0.6) x 10(9)/l. The plasma (268 g) contained 5.4 g/dl of total protein, and only a few blood cells; clotting factor VIII activity 75%, all satisfying the guidelines.

Blood Component Removal↗