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T Mazda

Publications and source records attributed to T Mazda.

32 records · Page 2Linked to original sources
PubMed1989

A serum protein SP40,40 modulates the formation of membrane attack complex of complement on erythrocytes.

SP40,40 was isolated from the soluble membrane attack complex (SC5b-9) by HPLC using a reverse-phase column. Amino acid compositions of its alpha- and beta-subunits were similar to each other with the exception of glycine content. Amino-terminal sequences of its alpha- and beta-subunits were identical to those of the subunits prepared from human serum, respectively, indicating that there was no degradation of SP40,40 during incorporation into SC5b-9. When guinea pig erythrocytes were incubated with C56f, C7, C8 and C9 in the presence of SP40,40, SP40,40 enhanced the hemolysis. The protein, however, inhibited the hemolysis when erythrocytes were pre-incubated with C56f and SP40,40 prior to the addition of C7, C8 and C9. These findings indicate that SP40,40 modulates the formation of membrane attack complex by interacting with C56f at the first step, and that the co-existence of other factors, besides C56f, is required for the enhancing activity of SP40,40.

Amino Acids↗
PubMed1989

Amino-terminal amino acid sequence and chemical and functional properties of a membrane attack complex-inhibitory factor from human erythrocyte membranes.

The protein corresponding to P-18 (Sugita et al. (1988) J. Biochem, 104, 633-637) was isolated from native human erythrocyte, and newly designated membrane attack complex-inhibitory factor (MACIF). The amino-terminal sequence of this protein was determined to be Leu-Gln-Cys-Tyr-Asn-Cys-Pro-Asn-Pro-Thr. Endoglycosidase F digestion of MACIF decreased its molecular weight by about 6K on SDS-PAGE. On the other hand, endoglycosidase H, neuraminidase, or endo-alpha-N-acetylgalactosaminidase treatment had no effect on the molecular weight, indicating that MACIF has complex-type N-linked oligosaccharide chains, but no O-linked chain. MACIF was highly resistant against trypsin digestion and heat treatment. The inhibitory activity of MACIF on the hemolysis of EC5-8 cells was comparable to that on EC5-7 cells, indicating that MACIF inhibited the binding of C9 to the intermediate cells, or the subsequent C9 polymerization.

Amino Acid Sequence↗
PubMed1989

Differences in substrate specificities for cysteine proteinases used in blood group serology, and the use of bromelain in a two-phase inhibitor technique.

Because substrate specificities differ between proteolytic enzymes and because knowledge of the optimal enzyme activity levels is necessary in order to standardize procedures used in antibody screening, a study was made of the best common assay method for the routinely employed enzymes bromelain, papain and ficin. Casein degradation was found better suited to this purpose than azoalbumin. With standardization achieved, a useful two-phase bromelain inhibitor technique was devised using bromelain at 20 casein units of activity. This method improved upon the one-stage bromelain technique in terms of sensitivity, freedom from false positive reactions and it compared well with the two-phase papain inhibitor technique.

Albumins↗
PubMed1987

The identification of inhibitors in bromelin one-stage irregular antibody screening techniques.

Human sera contain bromelin inhibitors in irregular antibody screening techniques. In order to identify and purify these inhibitors, pooled human sera were precipitated with ammonium sulfate, followed by DEAE-cellulose and Sephadex G-150 column chromatography. Proteinase activity and inhibitory activity to bromelin were observed in two protein fractions, these were identified as alpha 2-macroglobulin and the S-2 thiol proteinase inhibitor.

Antibodies↗
PubMed1987

Standardization of bromelin for use in routine one-stage antibody screening.

A simple standardization method for bromelin used in routine one-stage antibody screening is described. Bromelin proteinase activity was assayed using casein as the substrate, and converted to units. The use of proteinase activity units for standardization of bromelin resolves differences between commercial preparations.

Bromelains↗
PubMedDate not supplied

The effects of pH and agitation on platelet preservation.

Platelet concentrates made with an initial pH of 7.85 or 6.85 by addition of alkali or acid were stored at 22 degrees C on tumbler or horizontal agitators. The combination of a high pH and use of a tumbler rotator was associated with a 40 percent reduction in platelet count, fragmentation of platelets, release of lactate dehydrogenase, and a marked loss in response to adenosine diphosphate. Similar, but less striking changes occurred in acidified platelet concentrates stored on the tumbler rotator. Preservation was good for both alkaline and acidified concentrates stored on the horizontal agitator. These in vitro studies showed that, even at a pH of up to 7.7, gently agitated platelets were relatively undamaged for up to 60 hours, while vigorous agitation destroyed platelets at the same pH.

Blood Platelets↗