Search PubMed⌕ Search

Biomedical subjects

D Strauss

Publications and source records attributed to D Strauss.

At least 91 records · Page 5Linked to original sources
PubMed1978

[Evaluation of internationally used blood stabilizers for effective erythrocyte substitution].

Haemotherapy developed in the direction of transfusing pure blood cell preparations, if possible and enlarging the therapy with plasma fraction considerably. Quality losses of haemotherapeutics will already occur when they are prepared. This is mainly due to the conditions of blood collecting, blood stabiliser, duration and storage temperature from the blood collecting to further processing as well as biological variability of the composition of the donor's blood. The amount of substrate available to erythrocytes differs in various blood stabilisers. Deplasmatized erythrocyte concentrates can be used after several weeks of storage, if a high glucose concentration is present in the blood stabiliser. In CPD media the function of erythrocytes, the oxygen supply of the tissue, will remain intact a week longer than in ACD media. This effect will be increased by xylitol and pyruvate as well as by adding bicarbonate simultaneously. In future a primary importance will have to be attached to an improved storage of erythrocytes in the form of resuspended buffy coat-free erythrocyte concentrates.

Adenine↗
PubMed1978

[Effect of dihydroxyacetone on metabolic parameters and survival of resuspended erythrocytes after storage at 25 degrees and 4 degrees].

Erythrocyte concentrates from CPD blood were resuspended after separating the leukocyte-thrombocyte layer and stored at 4 degrees C and 25 degrees C. The solutions for resuspension differed in the content of substrate, pH, condition of sterilization and the resuspension volume used, 1 or 4 volumes of cell concentrate to 1 volume of resuspension solution. At 4 degrees C, there was no effect of DHA on the the 2.3 bisphosphoglycerate content (P2G content). The decreased activity of triokinase at low temperature, phosphate deficiency and a partial disintegration of DHA during the autoclave as well as the difference of the commercial DHA preparations are discussed as underlying causes. At 25 degrees C DHA delayed the P2G decrease during storage. The enhanced triokinase activity above 15 degrees C is principally considered to be the cause for it. High rates of haemolysis, rapid ATP decrease, survival rates of 56% after a storage of three weeks for erythrocyte resuspensions with DHA in used compositions render a clinical application impossible at present. It could be well suitable as a substrate for resynthesizing P2G. An addition of ascorbate + nicotinamid + adenin at a storage temperature of 4 degrees C had no influence on the P2G content. A resuspension solution on the basis of xylitol with additions of sorbitol, bicarbonate, inorganic phosphate, pyruvate, adenine and guanosine showed the best properties in the content of P2G and ATP, lactate formation and survival rate during a storage at 4 degrees C.

Adenosine Triphosphate↗
PubMed1977

[Effect of violamycin BI on the process of excision repair in Escherichia coli K 12 following UV irradiation].

The influence of violamycin B I on the process of excision repair of DNA-damages after UV-irradiation has been studied by observing the capacity to rejoin single-strand breaks introduced in the DNA at the beginning of the repair process. The number of single-strand breaks remaining unrepaired in the DNA was higher in presence of violamycin B I. Sedimentation analysis of the DNA of unirradiated cells showed in presence of violamycin B I only a small change in the molecular weight. As a possible reason for the lower capacity of the cells to accomplish repair steps following incision in presence of violamycin B I an inhibition of the function of repair enzymes by interaction of the antibiotic with the DNA-template is discussed.

Aminoglycosides↗
PubMed1977

[Effect of the addition of antibiotics on the fattening capacity of broilers fed optimum rations. 4. Lambdamycin].

A total of 3426 broilers were used in 3 fattening trials. The birds received supplements of the antibiotic lamdbamycine in amounts of 30 or 40 mg per kg of feed added to adequately balanced fattening rations. OTC supplements (40 mg per kg) which were an obligatory food component at the time of the trial were used as controls. The results obtained may be summarized as follows: Supplements of neither lambdamycine nor oxytetracycline exerted any significant influence on food consumption. Lambdamycine improved the rate of liveweight gains by 2% (trial 1, alpha greater than 0.05) and 5% (trial 2 and 3; trial 2: alpha less than 0.05, trial 3: alpha greater than 0.05). The growth-promoting effect of OTC was less pronounced than usual (2-3%; alpha less than 0.05) or was completely absent (trial 2). Lambdamycine decreased the rate of food consumption per unit of weight gain in 2 trials (trial 2: alpha less than 0.01) OTC did not influence the rate of food consumption.

Animal Feed↗
PubMed1977

[Proof of sex-dependent effect of lambdamycin in mice].

The juvenile mouse is used as screening model to test feed additives for their potentially ergotropic effects. Weight development in 20-day old mice was found to be much more strongly influenced than in animals being 25 to 30 days old. The antibiotic lambdamycin inhibited weight gain in female mice, whilst males were promoted in weight development following lambdamycin application.

Analysis of Variance↗
PubMed1977

[Viability, ATP and 2,3-DPG content of resuspended erythrocytes during several-week storage in cold].

Leukocyte-and thrombocyte-poor packed red cells obtained from ACD or. ACD-AG blood were resuspended to a hematocrit of about 55% and stored at 4 degrees C. The resuspension solution consisted of xylitol, inorganic phosphate, bicarbonate, adenine (A) and guanosine (G) solved in water. In one case glucose, citrate and sucrose were also added, in another one, sorbitol. The 2,3-DPG and the ATP level remained for a longer period in the sorbitol-xylitol-medium than in the glucose-xylitol-medium. The ATP content in the red cell suspension was higher than in packed cells. Higher ATP values were obtained in red blood cells from whole blood with adenine and guanosine. The survival rate of resuspended red blood cells in glucose-AG-citrate-sucrose medium was about 80--85% after 3 weeks of storage and 77% after 6 weeks with a higher range.

Adenosine Triphosphate↗
PubMed1977

[Adenine nucleotide- and 2,3-diphosphoglycerate metabolism in human erythrocytes in chronic kidney insufficiency].

In 38 patients with chronic renal insufficiency of different degree of severity examinations of the stationary concentration of the adenine nucleotides in the erythrocytes were carried out. It was shown that in the red blood cells of uraemics a genuine increase of the concentration of these compounds occurs, in which case the adenosine triphosphate dominates absolutely as well as relatively. In individual cases erytho-cyctic ATP-values of more than 3 micron mol pro ml cells may be achieved. The increase of the ATP-concentration in the red blood cells correlates with the degree of severity of the renal insufficiency and the renal anaemia. The hyperphosphataemia occurring as a rule in renal insuficiency is of causal importance for the increase of ATP. By a consecutive increase of the intracellular phosphate level and by influence on different steps of enzymes (phosphofructokinase, aldolase, glycerin aldehyde phosphate dehydrogenase) and changed regulations it effected an activation of the glycolysis. The increase of the plasma adenine and plasma adenosine concentration plays apparantly an accessory role for the increase of the concentration of the adenine nucleotides existing in the erythrocytes. Together with an increased concentration of 2,3-diphosphogycerate (2,3-DPG) the increase of the ATP-level has an effect on the oxygen transport function function of haemoglobin in the sense of a facilitation of the O2-output. These processes explain the relative adaption of patients with chronic renal insufficiency to renal anaemias of partly high degree.

Adenine Nucleotides↗
PubMed1976

[Lambdamycin, an antibiotic from Streptomyces glaucoachromogenes Prauser strain MET 31118].

Lambdamycin-producing strains were detected by means of the BIP test method. The isolation technique and the physicochemical and biological properties of lambdamycin, an antibiotic produced by Streptomyces glaucoachromogenes, are described. Lambdamycin is a yellow-green pigment of the chromoglycoside type. Digitalose and fucose are the sugar components. The physicochemical properties of lambdamycin resemble those of chartreusin. However, the known biological activity is different. The antibiotic can be isolated from culture filtrates and from the mycelium by extraction with lower aliphatic alcohols. It can be purified by gel filtration methods. Lambdamycin displays antimicrobial activity, particularly against grampositive bacteria. Strains which produce enzymes inactivating different commercial antibiotics are also inhibited. Moreover, lambdamycin shows antiviral activity, as well as cancerostatic and ergotropic action in vitro and in vivo. The acute LD50 of lambdamycin in mice after 21 days was greater than 125 mg/kg when administered intraperitoneally.

Animals↗
PubMed1976

[Autologous transfusion of erythrocytes with high or low concentration of 2,3-diphosphoglycerate. Survival rate and time and hemoglobin-oxygen affinity].

1. In human erythrocytes the 2.3 DPG concentration was increased three to fourfold of the norm as IPP re-suspension by an incubation time of four hours at 37 degrees C or as ACD-AG blood was lowered below 20% of the norm respectively. After an autologous transfusion the 24 hours' surviving rate and the apparent half survival time of cells as well as the affinity of haemoglobin to oxygen in the total blood were measured. 2. The 24 hours' surviving rate for fresh erythrocytes with increased 2.3 DPG and ATP concentration amounts to 73% and the apparent half survival time amounts to 6 days. If erythrocytes are stored for four weeks as IPP resuspension at 4 degrees C, the 24 hours' surviving rate is 59%. Erythrocytes from fresh ACD-AG blood with lowered 2.3 DPG and a normal ATP concentration have a 24 hours' surviving time of 85% and an apparent half survival time of 24 days. 3. After autologous transfusion of 400 ml of erythrocytes with increased 2.3 DPG concentration the P50 value of the total blood will increase by 3 mm of Hg, after administering 400 ml of erythrocytes with lowered 2.3 DPG concentration it will fall by 1.8 mm of Hg. 4. The findings are discussed in connection with the significance of the changes of affinity of haemoglobin to oxygen produced by 2.3 DPG for the oxygen supply of tissues and under the aspect of using stored blood with increased 2.3 DPG concentration for practical purposes.

Blood Transfusion, Autologous↗
PubMed1975

Leukaemomycin, an antibiotic with antitumor activity. I. Screening, fermentation, and biological activity.

A Streptomyces strain belonging to S. griseus (Krainski) Waksman et Henrici 1948 sensu Hütter (1967) was found to produce an antibiotic designated as leukaemomycin. The red-pigment antibiotic, having antimicrobial and antitumor activity in vitro and in vivo, was isolated from C-, N-, and Fe-containing cultures of the strains IMET JA 3933, IMET JA 5570, IMET JA 10086, and IMET JA 10431. Leukaemomycin has indicator properties and is produced by the classic procedures of submerged fermentation. The crude base of leukaemomycin consists of 4 main components, designated as leukaemomycin A, B, C, and D. The biological activity of the main components leukaemomycin B and C was compared. The biological activity and the physicochemical properties of leukaemomycin C are identical with known properties of the anthracycline antibiotic daunorubicin.

Animals↗
PubMed1975

[Biosynthesis and the isolation of the new anthracyclin antibiotics, violamycins A, BI, BII and their aglycones].

The conditions of fermentation, isolation and some of the physico-chemical properties of the new anthracycline antibiotics, i. e. viomycin A, BI, BII and their aglycones, produced by a strain of Streptomyces violaceus IMET JA 6844 are described. Violamycin A is mainly a complex of aminoglycosides of epsilon- and dzeta-isorhodomycinone, beta-rhodomycinone and (alpha)2-rhodomycinone. The sugar component is rhodosamine. Violomycin BI is mainly a complex of trisaccharides of the same aglycones mentioned above. The sugar components are rhodosamine, 2-desoxy-L-fucose and rhodinose. Violomycin BII is mainly a rhodosaminyl-2-desoxy-L-fucosyl-derivative of epsilon- and dzeta-isorhodomycinone, beta- and epsilon-rhodomycinone and (alpha)2-rhodomycinone. Violamycin complexes A, BI, BII mainly consist of 6 aglycone components which are similar to the other members of anthracyline antibiotics but can be diferentiated from them by physico-chemical and biological properties. Epsilon- and dzeta-isorhodomycinone, epsilon- and (alpha)2-rhodomycinone and dzeta-rhodomycinone one of the 8 minor components contained in the mixture of the aglycones of the violomycin complex so far has been determined as constituents of an antibiotic.

Aerobiosis↗
PubMed1975

[Further improvement of the ACD-AG protective solution for blood. II. Behavior of the oxygen affinity of preserved blood in ACD-AG medium and in a protective solution with addition of pyruvate and xylitol and elevated Ph values].

The present paper deals with the behaviour of the oxygen transport function as well as the 2.3 DPG and ATP levels of erythrocytes during the storage in an ACD-AG solution. In the ACD-AG blood in P 50 fell from 20mm of Hg to values of 12 mm of Hg within 4 weeks of storage. The 2.3 DPG content had already fallen to values below 10% within a fortnight. Additions of xylitol (10 mM in the blood) and pyruvate (0.3 mM in the blood) will delay the decrease of P 50 and the 2.3 DPG content. Concerning the ATP behaviour there was no significant difference between ACD-AG blood and that with additions of xylitol and pyruvate. Up to a storage of a fortnight stored blood in the ACD-AG solution of xylitol and pyruvate will be equal to ACD-AG fresh blood as far as the parameter of oxygen transport function is concerned.

Adenosine Triphosphate↗
PubMed1975

[Further improvement of the ACD-AG protective solution for blood. III. Improvement of the oxygen transport function of erythrocytes in sorbitol xylitol pyruvate solutions with elevated Ph].

If the pH value in the ACD or in the ACD-AG storage solution is enhanced, the glucose in the autoclaving with undergo a caramelizing process. For this reason glucose was replaced by sorbite in the storage solutions with a pH value of 6.0 and additions of xylitol and pyruvate. The initial pH value in the blood amounted to 7.3. The content of 2.3 DPG of the erythrocytes remained fully preserved in the blood with sorbitol and additions of xylitol and pyruvate during the first 2 weeks of storage and decreased to 30% only in the third week. There were only slight amounts of 2.3 DPG in the ACD-AG blood at that time of storage. Up to the third week of storage the ATP content of erythrocytes as well as the haemoglobin level in the plasma revealed no essential differences between stored blood with sorbitol and xylitol as a substrate or glucose + xylitol respectively. The quick decrease of the ATP level to zero and the simultaneous strong increase of haemolysis in the sorbitol blood within the fourth week of storage is discussed in connection with a lowering of the NAD/NADH2 quotient. For the purpose of keeping the 2.3 DPG level of erythrocytes a storage solution with sorbite and xylitol (ASCX-AG-Pyr 10mM) seems to be well suited for a storing time of 2---3 weeks at first.

Adenosine Triphosphate↗
PubMed1975

Leukaemomycin, in antibiotic with antitumor activity. II. Isolation and identification.

A Streptomyces strain belonging to Streptomyces griseus (Krainsky) Waksman et Henrici 1948 sensu Hütter (1967) was found to produce the red-pigment antibiotic leukaemomycin. The antitumor active antibiotic was isolated from the culture broth and purified by ion-exchange processes. The crude base of leukaemomycin mainly consists of 4 components with biological activity. The base-complex was separated by counter-current distribution into the biological active leukaemomycins B1, B2, C, and D. The single components of leukaemomycin were compared with the anthracycline antibiotics daunomycin, dihydrodaunomycin, and adriamycin. The analytical procedures allowed to state the identity of leukaemomycin B1 with rubomycin B, leukaemomycin C with daunomycin, leukaemomycin D with dihydrodaunomycin and allowed to suggest the identity of leukaemomycin B2 with daunosaminyldaunomycin. Formulas and physicochemical data are given. Bio-assay methods are described to determine leukaemomycin B complex beside leukaemomycin C.

Antibiotics, Antineoplastic↗