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Biomedical subjects

V Kretschmer

Publications and source records attributed to V Kretschmer.

18 recordsLinked to original sources
PubMed1992

Superiority of gel centrifugation in antibody screening and identification.

We report on the direct comparison of gel centrifugation technique and tube testing for antibody screening (ABS) under controlled routine conditions. 3,000 blood samples were screened for antibodies (AB) by gel centrifugation (ID-System, bromelin 37 degrees C and room temperature, indirect antiglobulin test with LISS) and a sensitive tube test (TT; bromelin two-phase test, 37 degrees C and room temperature, and indirect antiglobulin test with 22% bovine albumin) in parallel. By ID significantly more relevant and potentially hemolytic AB (51 vs. 35 AB/1.7 vs. 1.2%) could be detected: anti-E 4, -C 1, -D 4, -CW 2, -c 2, -Jk(a) 2, -Jk(b) 1. Eleven of these even remained negative in TT when retested with increased sensitivity and taking additional (homozygous) test cells. In addition, naturally occurring but rarely hemolytic AB (35 vs. 23 AB/1.2 vs. 0.8%) were more frequently detectable by ID: anti-Le(a) 6, -Le(b) 2, -P1 6. In contrast, only two AB were only positive in TT: anti-Le(a) 1, -Le(a, b) 1. The main disadvantage of the ID was its frequent positivity (7.7 vs. 4.3%) due to irrelevant cold AB (anti-I, -HI, -H) and unspecific factors. This can be partly reduced by omission of the bromelin test at room temperature (ID 3.0%, TT 1.5%) as the detection of relevant AB is not affected. The frequency of naturally occurring AB was still the same as in TT (0.7%) when bromelin at room temperature was omitted in both techniques. Further advantages of the ID are simplicity, small volumes of sera and reagents, and easy evaluation.

Blood Grouping and Crossmatching↗
PubMed1992

Improvement of the separation of blood by modification of separators Optipress and Biotrans Separator.

UNLABELLED: By use of the new top-and-bottom bag system and automatic separators the quality of red cell concentrates (RCC) and fresh frozen plasma (FFP) could be markedly improved. Simultaneous preparation of storable single-donor platelet concentrates (PC) resulted, however, in too high losses of red cells and plasma. Through modification of the pressure plate of the separators and variation of the residual buffy coat (BC) volumes we tried to optimize the separation in this respect. In a second study we tried to establish the preparation of platelet-rich plasma (PRP) using top-and-bottom bag systems and automatic separators. MATERIALS AND METHODS: 1st study: 149 whole-blood units (Biopack U, quadruple systems) were separated into components either with Optipress (Opt, n = 58) or with Biotrans Separator (Bio, n = 91). To Optipress additional plates, 3-6 mm thick, were attached and the residual BC volume was varied by different adjustments of the distance screw. The Biotrans Separator was used with a plane pressure plate as well as with a modified plate having a transverse groove; the residual BC volume was adjusted to 50-120 ml. 2nd study: 15 whole-blood units were separated into PRP and RCC either using the Optipress (standard version, n = 5) or the Biotrans Separator (alternating opening of clamps, standard plate, n = 10). RESULTS AND CONCLUSIONS: 1st study: Both separations could be improved. The loss of red cells was significantly lower in case of the Biotrans Separator: Bio 15.6%, Opt 25.9%, p < 0.001. Other separation parameters showed no relevant difference between both separators. 2nd study: By use of the Biotrans Separator significantly less platelets could be separated (Bio 75.1 x 10(9), Opt 87.0 x 10(9), p < 0.05), but the PRP clearly was contaminated with less leukocytes (Bio 51.0 x 10(6), Opt 458.9 x 10(6), p < 0.01). The contamination of the RCC with leukocytes (about 20%) was markedly improved in both methods when compared with conventional preparations. The mean loss of red cells was 12.8% in both methods.

Blood Component Removal↗
PubMed1992

[Filtration of buffy coat-free erythrocyte suspensions in additive solution].

Buffy coat-free red cell concentrates in SAG-M (RCC) were produced by BAT system (leukocyte content 132 x 10(6)/RCC). They were stored for 4 weeks and filtered by Erypur Optima (E), Sepacell R 500 B (S) und PALL RC 50 TM (P). Leukocyte depletion was very effective (E: 0.56 x 10(6)/RCC; S: 0.36 x 10(6)/RCC; P: 0.55 x 10(6)/RCC) but hemolysis was remarkable (E: 301 +/- 195; S: 127 +/- 123; P: 368 +/- 256 mg/RCC). Therefore preparation of two RCC per filter was only acceptable with S. In S and P loss of red cells was tolerable (E: 90.5; S. 41.8; P: 38.2). In contrast, E should be rinsed with sodium chloride at the end of the preparation. In E and S filtration times were short without additional pressure (E: 6.6 min; S: 4.7 min; P: 20.3 min). We conclude from our results that the use of buffy coat-free red cell concentrates in additive solution considerably reduces the problems of filtration, e.g. storage interval, leukocyte reduction, hemolysis, filtration flow. Despite this, bedside filtration is not recommended because quality assurance is necessary.

Blood Component Transfusion↗
PubMed1992

[Production of rejuvenated and stable, leukocyte depleted erythrocyte concentrates using the heated centrifugation method].

We report on an alternative to filtration for the preparation of leukocyte-poor red cell concentrates (LP-RCC). It is based on the method of Schneider. Using RCC with buffy coat it is comparably effective in leukocyte reduction [98.3 +/- 1.0%, (3.7 +/- 2.6) x 10(6) leukocytes] and more effective in platelet reduction (96.9 +/- 2.5%). Addition of PAGGS-M before heating (30 min, 37 degrees C) as well as after preparation significantly reduces hemolysis (free hemoglobin, LDH, HBDH) and improves the quality of the LP-RCC (ATP, 2,3-DPG) during storage for 24 h after preparation. LP-RCCs prepared with PAGGS-M after 6-day storage show still better quality than before preparation and about the same quality as LP-RCCs 24 h after conventional preparation with saline solution. In conclusion, by use of PAGGS-M and sterile docking LP-RCCs of adequate quality for 6-day storage can be prepared, improving the supply of the patients concerned.

Adenine↗
PubMed1992

[Superiority of the gel centrifugation method (ID System) in detection of erythrocyte antibodies].

We report on the direct comparison of gel centrifugation technique and tube testing for antibody (AB) screening (ABS) under controlled routine conditions. 3,000 blood samples were screened for AB by gel centrifugation (ID-System, bromelin 37 degrees C and room temperature, indirect antiglobulin test with LISS) and a sensitive tube test (T; bromelin two-phase test 37 degrees C/room temperature and indirect antiglobulin test with 22% bovine albumin) in parallel. By ID significantly more relevant and potentially hemolytic AB (51 vs. 35 AB/1.7 vs. 1.2%) could be detected: anti-E 4, anti-C 1, anti-D 4, anti-CW 2, anti-C 2, anti-Jk (a) 2, anti-Jk (b) 1. 11 of these even remained negative in tube test when retested with increased sensitivity and taking additional (homozygous) test cells. In addition, naturally occurring but rarely hemolytic AB (35 vs. 23 AB/1.2 vs. 0.8%) were also more frequently detectable by ID: anti-Le (a) 6, anti-Le (b) 2, anti-P1 6. In contrast, only two AB were only positive in T: anti-Le (a) 1, anti-Le (ab) 1. The main disadvantage of ID was its frequent positivity (7.7 vs. 4.3%) due to irrelevant cold AB (anti-I, anti-HI, anti-H) and unspecific factors. This can be partly reduced by omission of the bromelin test at room temperature (ID 3.0%, T 1.5%) as the detection of relevant AB is not affected. The frequency of naturally occurring AB was still the same as in T (0.7%) when bromelin at room temperature was omitted in both techniques. Further advantages of ID are simplicity, small volumes of sera and reagents and easy evaluability.

Blood Group Antigens↗
PubMed1979

[Simplification of the Papanicolaou stain which is easily reproducable (author's transl)].

A simple and well reproducable modification of the Papanicolaou stain is reported. The most important modification is the replacement of the natural stain hematoxyline by the qualitively excellent synthetic stain thionin which is immediately added to the alcoholic fixation solution for a fixation stain. The high labor intense alternation between alcohol water and alcohol is thus eliminated. The quality of the nuclear staining is very good. The fixation staining with thionin without counter-staining of the cytoplasma may be used for a rapid thionin stain which gives sufficient cytoplasmatic staining by the thionin for a rapid cytological smear for cancer. The counter-stain of the cytoplasma was also simplified. The over-all staining of this simplification of the pap smear is comparable to that of the original papanicolaou stain. This modification of the papanicolaou stain fulfills requirements which a stain in competition with the original papanicolaou stain should have. 1. The modification is qualitively equal to the original method, 2. the staining method is simpler, 3. the staining method is well reproducable, 4. the staining method is more economical.

Female↗
PubMed1978

[Current status of granulocyte separation and transfusion].

Granulocyte substitution therapy is of definitive clinical value when correctly indicated and consequently performed. Comparing the different techniques for leucocyte separation, the combination of continuous flow centrifugation (CFC) and filtration (FL) permits the highest yield of granulocytes. As yet, all available methods imply a rather high degree of inconvenience and a considerable rate of side effects for the (normal) donor which cannot easily be justified from a medical point of view. On the other hand, CFC and especially FL have a great potential for further improvement. Hence, higher yields and less donor affection are expectable. Granulocyte procurement is a great challenge to existing transfusion centres requiring their future engagement and expansion in this new and important field.

Blood Transfusion↗
PubMed1977

An improved modification of cycle filtration leucopheresis.

We report about an own modification of repetitive cycle filtration leucopheresis (RFL). Compared to the method described by De Fliedner et al. (1974) it is simpler to perform, permits the use of commercially available filtration sets and thus reduces the costs of the procedure considerably. The mean yields of the granulocytes collected in 51 RFL from unconditioned normal donors amounted from 1.7 to 2.3 X 10(10) dependent on the number of the filtration cycles performed.

Blood Donors↗
PubMed1977

Significance of complement activation in autoimmune haemolytic anaemia of "warm type".

To study possible relationships between serum C3 and C4 levels and fixation of complement components (C) on red cells, 79 patients of autoimmune haemolytic anaemia of warm type (AIHA) and 7 patients of various diseases with positive direct antiglobulintest (DAT) but without haemolysis were investigated. 23 out of 79 patients with AIHA were analyzed repeatedly during the course of the disease. There were no significant differences of C levels between the various clinical types. However, the number of patients with reduced levels of C3 and C4 was significantly higher among cases with C fixation on the red cells than among those with fixation of immunoglobulins alone. Changes were more pronounced for C4 than C3 and mean values of serum C4 were significantly lower in the group with C fixation. If incomplete warm haemolysins were demonstrable, C4 levels were lower than in cases without warm haemolysins. During the clinical course, C3 and C4 concentrations showed a close correlation to the severity of haemolysis.

Anemia, Hemolytic, Autoimmune↗
PubMed1977

[Automatic data processing for organisational aid to blood donor centers in emergency hospitals].

A test model of a computer-off-line system at the Community Hospital Blood Bank in Herford collecting approximately 3.000 units of blood annually is described. The computer system presented, now in operation for more than one year, has proven its value for general blood bank administration by its time-saving effect and the optimalized documentation of donor- and blood-related data. The computer system described is particularly recommended for smaller, hospital-based blood transfusion services. Its introduction is even justified in institutions preparing less than 5.000 units of blood per year. Prerequisite for an economical operation of the computer system is the participation of the hospital management in other computer activities, i.e. book-keeping, accounting etc.

Blood Banks↗
PubMed1977

Reappraisal of the clinical and etiologic significance of immunoglobulin deviations in autoimmune hemolytic anemia ('warm type').

56 patients with autoimmune hemolytic anemia ('warm type') (AIHA) were investigated for immunoglobulin deviations. Of these, 43 were repeatedly analyzed (mean 4 times). The mean observation time was 20 months. The immunoglobulin values were correlated with clinical (degree of hemolysis) and serological (immunoglobulin class of autoantibodies; strength of antiglobulin reaction) parameters and statistically evaluated by variance analysis. Although no significant deviations of immunoglobulins in AIHA were found as compared to a normal control group, the immunoglobulin disturbance most frequently seen was an elevation of IgM. This is interpreted as a possible lack or functional impairment of immunoregulatory T cells in AIHA.

Analysis of Variance↗
PubMed1976

[Can azur-B eosin replace the May-Grünwald-Giemsa stain?].

A new method is described for staining blood and bone marrow smears. It is characterized by the presence of only two dyes, purified azure B and eosin in methanol, as stock solutions. Staining results are equivalent to those obtained by using the traditional dye mixtures according to May and Grunwald, Giemsa, Leishman or Wright. Different from these azure B-eosin staining can be standardized and is easier to be handled. Correlations between the azure-B-eosin and May-Grunwald-Giemsa (MGG) staining methods are briefly discussed.

Blood Cell Count↗