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Biomedical subjects

G Matthes

Publications and source records attributed to G Matthes.

At least 37 records · Page 2Linked to original sources
PubMed1994

[Metabolic and rheologic changes in long-term hypothermia of erythrocyte concentrates over 15 weeks].

With a multiple washing procedure in a chloride ion-free citrate-phosphate-glucose-adenine additive solution or with storage of red blood cells in a large volume of this solution, erythrocytes can be stored for 15 weeks at 4 degrees C. After 12 weeks' storage in this chloride-free solution the red blood cell parameters (2,3-DPG, glucose, lactose) measured are as good as stored erythrocytes resuspended in SAG-Mannitol after 21 days. Rheological parameters (morphology, filterability) show a maintenance of deformability of such preserved cells up to 84 days of storage. The preservation of erythrocytes by this method has the advantage that beside the hypothermic long-term storage (potential second aHIV screening of blood donors) the blood is of better quality in the first weeks of storage.

2,3-Diphosphoglycerate↗
PubMed1994

[Large volume lymphocytapheresis for the collection of peripheral stem cells].

We performed 29 large-volume leukaphereses of 20 patients for collection of peripheral blood stem cells. All patients have been pretreated with cytokines after chemotherapy. In 9 patients with precounts of > or = 3 x 10(9) mononuclear cells/l we achieved a sufficient transplantation doses with one LVL. If the MNC precount was < or = 3 x 10(9)/l we had to perform more than one LVL. On 16 patients we compared a standard apheresis procedure with the LVL procedure. It seems that especially patients with a lower MNC precount can profit from LVL. From patients with higher MNC precounts we harvested the double amount of MNCs, from patients with lower MNC precounts the triple amount.

Female↗
PubMed1994

[Improvement of storage capability of blood by the use of biocompatible absorbents].

A new filtration method for leucocyte and chloride ion depletion of erythrocyte concentrates in one step by DEAE cellulose was developed. After passage of the packed red cells through this filter material a chloride depletion of 70-80% and a leucocyte depletion of 90% could be reached. The 25 degrees C storage of this in-line-filtered red cells characterized by metabolic parameters (ATP, 2,3-DPG) suggests the possibility of a long-term red blood cell storage.

Absorption↗
PubMed1994

[Mechanical separation of erythrocyte concentrates and fresh plasma in autologous blood transfusion using Haemonetics MCS-3P].

The application of an autologous blood programme in hospitals is often limited by missing preconditions such as equipment, room, or staff. A component therapy in autologous blood donation is now easily possible by an automated whole blood donation with cell separator MCS-3P which allows in one step the collection of one unit red cell concentrate and one unit of plasma in 7 min. The quality of the collected blood preparations meets the requirements.

Blood Preservation↗
PubMed1994

[Rejuvenation of autologous blood preserved by washing in glucose- adenine- phosphate- and citrate-containing solution].

Outdated red cell concentrates (RCC-SAGM) were washed with a chloride-free, glucose-adenine-phosphate-citrate preservation solution. After resuspension of the red cells in this solution a hypothermic storage for additional 63 days was performed. Quality parameters (2,3-DPG, glucose, lactose, free hemoglobin, pH, chloride, pO50, shape quality index, filtration index) of the preserved red blood cells became normal within 7-11 days after the rejuvenation procedure. The data prove that a rejuvenation of outdated blood by a simple washing procedure allows a post-storage time of 21 days.

Adenine↗
PubMed1994

[Mechanical donation of whole blood simultaneous extraction of concentrated erythrocytes and fresh plasma using MCS-3P].

The new 'Multi-Component System-3 pump' (MCS-3P) is an apheresis system giving the flexibility to collect red blood cells, plasma, and platelets in one step. The objective was to perform an automated donation of red cells and plasma (erythroplasmapheresis), collecting in less than 20 min 350 ml red cells including 80 ml of SAG-M and 400 ml plasma. For this study we have evaluated 32 donations. The results obtained for red blood cells (42 days) and plasma (after freezing) are as good as with standard collection (parameter such as Hb, Hk, MCV, MCHC, 2,3-DPG, ATP, free Hb and potassium, glucose, lactose, protein).

Adult↗
PubMed1994

[Autologous fibrin glue from preoperative blood or plasma donors].

Cryoprecipitate was prepared from autologous plasma donation (fresh frozen plasma). The composition of this cryoprecipitate (fibrinogen, factor XIII, fibronectin) meets the requirements for the fibrinogen component of a fibrin glue. The prepared glue has tensile strength values in dura mater gluing as good as the commercial tissue glues.

Blood Donors↗
PubMed1994

[Stem cell pheresis and deep temperature preservation--a problem of transfusion medicine?].

In Germany, Transfusion Medicine belongs to various medical disciplines. We would like to demonstrate our model of interdisciplinary collaboration in stem cell transplantation. Since 1989 we performed 339 leukaphereses in 53 patients. On average we got 1.4 x 10(8) MNC/kg body weight from one single apheresis procedure. To observe graft quality we measured the content of CD34-positive cells and the amount of CFU-GM. Despite diagnosis and therapeutical regimen the content of CD34+ cells was found to be 3.3% (0-20). The proliferation was 21.7 GM-CFU per 1 x 10(5) MNC seeded (0-393). The results of the first 17 transplantations showed a fast haematological recovery (WBS 1.0 Gpt/l after 9 days Plt 20 Gpt/l after 11 days). Close collaboration of Transfusion Medicine and Haematology leads to optimization of stem cell transplantation.

Blood Transfusion↗
PubMed1993

Posttransfusional changes of 2,3-diphosphoglycerate and nucleotides in CPD-SAGM-preserved erythrocytes.

BACKGROUND: Posttransfusional changes of preserved red blood cells can influence the oxygen equilibrium curve which is mainly affected by the concentration of erythrocyte 2,3-diphosphoglycerate (DPG). MATERIAL AND METHODS: The regeneration kinetics of DPG and nucleotides (ATP, ADP, AMP, GTP, GDP) was determined over a period of 0-48 h in surgically treated patients following transfusion of DPG-depleted packed red cells stored for 14 days in CPD-SAGM. RESULTS: 3 h after transfusion the DPG levels raised up to 40% of the patients' prior DPG concentrations. Complete regeneration of the DPG concentrations occurred 36-48 h after transfusion. Changes in the nucleotide pattern indicate, after a temporary decrease of ATP and GTP levels (after 10-30 min) and an activation phase (after 3-12 h), the full regeneration of these parameters 24-48 h after transfusion. CONCLUSIONS: The regeneration kinetics of DPG should be taken into consideration for transfusions with blood units stored for more than 14 days, especially in patients with reduced compensatory mechanisms (coronary and cerebral scleroses, pacemaker, etc.) and large transfusion volumes.

2,3-Diphosphoglycerate↗
PubMed1992

Age-dependent regeneration of plasma proteins after donor plasmapheresis.

To analyze age-dependent effects of a plasma donation on the regeneration of plasma proteins two groups of first time plasma donors were selected (less than 25 years, greater than 50 years). By measurements of hematological and biochemical parameter, immunoglobulins, procoagulators and inhibitors of coagulation before and after a plasma donation the kinetic of regeneration until three weeks was followed up. It can be concluded that a single plasma donation affects the generation in younger and older donors in a different way. Procoagulators and inhibitors show the same behavior, except the donation related elevation of fibrinogen in young donors. Especially the retarded regeneration of cholinesterase and immunoglobulins in the male young group should be taken into consideration for frequent plasma donations and autologous preoperative plasma donations.

Adult↗
PubMed1992

Platelet apheresis with Vivacell BT798 DEA, haemonetics V-50 and PCS-Plus: preparation efficiency and product quality using identical donors.

Different platelet apheresis techniques were used for preparing platelet concentrates: the continuous flow method with Vivacell BT 798 DEA, the discontinuous flow method with V-50 of Haemonetics, and their plasmapheresis device PCS-Plus. 20 of our donors underwent all three procedures. All platelet separations led to suitable platelet concentrates of 3 x 10(11) platelets within less than 90 min. However, the contaminating leukocytes reached 2 x 10(8). Due to less intense citrate reactions and a shorter donation time the donor acceptance of the continuous flow method was higher as compared with the discontinuous flow method.

Adult↗
PubMed1992

[Permselect--a new substance for leukocyte elimination].

Permselect particles consisting of purified plant cell wall ghosts obtained from the biomass of a suspension culture of Chenopodium album L. show a very high efficiency for leukocyte binding. A package containing 1 g dry Permselect eliminates 99-100% of leukocytes from 80 ml of fresh blood, preserved whole blood, or red blood cell concentrates. At comparable conditions Permselect shows a higher efficiency of leukocyte binding than commercial filter material (cotton, cellulose acetate). The vitality parameter of filtered erythrocytes and their stability during storage were not altered. The data are discussed with respect to causality of leukocyte binding to the pectin-containing surface of the cell wall particles.

Adsorption↗
PubMed1992

Age-dependent regeneration of plasma proteins after donor plasmapheresis.

To analyze age-dependent effects of a plasma donation on the regeneration of plasma proteins, two groups of first-time plasma donors were selected (< 25 and > 50 years). The regeneration kinetics of different plasma proteins until 3 weeks after donation was followed up. It can be concluded that a single plasma donation has an age-dependent effect on regeneration, especially on the prolonged regeneration of cholinesterase and immunoglobulins.

Adult↗
PubMed1991

Aortocoronary vascular prosthesis made of siliconized homologous vein or bovine sacral artery.

The purpose of our study was to develop and prepare aortocoronary prostheses, test them experimentally in multivascular and coronary reoperations in case of missing autologous grafts and to use them for shunt operations in cardiac surgery. Human vein or bovine sacral artery were used for preparing aortocoronary prostheses. As for metrics of 9-14 Charr. and a length of 20-30 cm were obtained. Aortocoronary prostheses were preformed according to the coronary configuration for left descending artery, circumflex artery and right coronary artery. Aortocoronary prostheses meet the conditions of desantigenicity, sterility, athrombogenicity, tightness and high tensile strength, tear propagation strength, bursting pressure and shrinkage temperature. Experimental testing was performed in dogs in aortofemoral and aortocoronary positions. Infections did not occur. The healing process and structural changes of aortocoronary vascular prostheses (grafts) were examined histologically and evaluated by means of scanning electron microscopic examinations. Athrombogenicity and healing-in without inflammation and calcification were proved.

Animals↗
PubMed1991

[Neonatal alloimmune thrombocytopenia--can cryopreserved thrombocytes help? (Case report)].

We present a case report of the transfusion of cryopreserved HPA 1-negative platelets to a newborn suffering from neonatal alloimmune thrombocytopenia (NAT). A boy weighing 3450 g, born of a HPA1-negative mother with a platelet count of 9 Gpt/l after delivery, received two transfusions of cryopreserved HPA1-negative platelet concentrates. The first transfusion resulted in a platelet increment to 32 Gpt/l (CCI 11). A second transfusion was needed after a further drop of the platelet count on day 4 to 18 Gpt/l, resulting in an increment to 64 Gpt/l (CCI 36). Normal development during the first six months was obtained. In our opinion, cryopreserved HPA1-negative platelets could be helpful in the therapeutical strategy of NAT.

Adult↗
PubMed1991

[Efficiency of mechanical plasmapheresis].

In a clinical study the automated donor plasmapheresis devices Autopheresis-C A 100, Plasmapur-Monitor, and Ultralite-PCS were tested. Including also manual plasmapheresis, we analyzed the efficiency of donor plasmapheresis, the reliability and breakdown susceptibility of the methods, the quality of the collected fresh plasma, and the suitability of the different machine plasmapheresis devices for routine application, using a total of 2,372 donor plasmaphereses. We also studied the behavior of some individual laboratory parameters due to plasmapheresis with Plasmapur-Monitor. The data allow us to recommend machine plasmapheresis for routine operation (Ultralite-PCS greater than Autopheresis-C A 100 greater than Plasmapur-Monitor).

Adult↗
PubMed1990

[Mechanical plasmapheresis by means of the Haemonetics-ultralite- plasma collection system: 2. Generation of platelet-rich plasma].

70 plateletpheresis were performed in a clinical study to evaluate the quality of platelet-rich-plasma prepared by the new developed Haemonetics-Ultralite-Plasmacollection system. The procedure took in average 54 minutes, resulting in a platelet content of 1.6 X 10(11) platelets. Platelets function (hypotonic stress response, ADP- and collagen-induced aggregation) was well maintained. The after differential centrifugation prepared platelet concentrate may be stored in the collection bag for 1 day at room temperature with acceptable functional recovery.

Blood Cell Count↗