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PubMed1992

Covalent binding of protamine by glutaraldehyde to bioprosthetic tissue: characterization and anticalcification effect.

Calcification is the principal cause of the clinical failure of bioprosthetic heart valves (BHV). The hypothesis of this work was that an impaired balance between positively and negatively charged amino acids, due to the reaction with Lys and Hyl tissue-collagen residues, expose affinity sites to Ca++. We further hypothesized that regardless of the cause(s) of BHV calcification, positive charge modification of the tissue will prevent their propensity to calcify. Modification of BHV tissue was obtained by covalently binding protamine sulfate, a polybasic peptide, via glutaraldehyde. The modification procedure resulted in stable, covalent links of approximately 5.3% w/w protamine with undiminished anticalcification properties, even after long storage. Significant prevention of calcification was exhibited by the p-bound tissue in comparison to BHV tissue, 66.0 and 106.5 micrograms/mg calcium, respectively, after 30 days of subdermal implants in rats. The results support our hypotheses, and orthotopical heart valve replacements are required in order to completely evaluate the treatment efficacy and biocompatibility.

Amino Acids↗
PubMed1992

Accessory sperm numbers for cattle inseminated with protamine sulfate microcapsules.

A study utilizing two morphologically distinct sperm populations in a heterospermic trial was conducted to evaluate the effect of microencapsulation on accessory sperm number in artificially inseminated cattle. Inseminates consisted of an equal number (100 x 10(6) of morphologically normal and tapered sperm. In reciprocal inseminates, one of the two sperm types was encapsulated in protamine sulfate microcapsules, and the other type was unencapsulated. Insemination of both sperm types that were unencapsulated served as the control. Thirty-one embryos were nonsurgically recovered 6 d postinsemination, and accessory sperm within the zona pellucida were counted and morphologically classified as normal or tapered. Microencapsulated sperm contributed 25.7% of the accessory sperm obtained for inseminates containing microcapsules. Microencapsulation did not affect the total number of accessory sperm per embryo; however, encapsulation did reduce accessory sperm for the specific sperm type encapsulated. The proportion of morphologically normal to total accessory sperm recovered were 65.8% when both sperm types were unencapsulated, 35.4% when normal sperm were encapsulated, and 80.6% when the tapered sperm were encapsulated. High accessory sperm numbers per embryo were related to embryo quality (P less than .01). Mean accessory sperm and standard deviations for degenerate embryos and for embryos classified fair to poor, good, and excellent were 1.7 +/- 2.9, 11.1 +/- 8.6 24.9 +/- 33.9, and 84.3 +/- 58.3. We conclude that sperm inseminated in protamine sulfate microcapsules can be released and can attach to the zona pelucida of ova in vivo. Microencapsulation failed to increase accessory sperm numbers under conditions of this experiment in which insemination was 12 h after estrus was first detected.

Animals↗
PubMed1999

Protamine-like sperm nuclear basic proteins in the primitive frog Ascaphus truei and histone reversions among more advanced frogs.

Sperm nuclear basic proteins (SNBPs) that condense chromatin are very diverse. In animals, evolution of SNBPs has proceeded from lysine-rich histone H type in sponges to more arginine-rich protamine-like PL and protamine P types. Yet sporadic PL/P to H reversions are known to occur in both protostomes and deuterostomes. To determine why this is the case, we have examined SNBPs in eleven anuran species. We find that sperm of the primitive, internally fertilizing archeobatrachian frog A. truei (family Ascaphidae) has PL/P type (42 mol % arginine), with an electrophoretic profile similar to SNBPs in another archeobatrachian, externally fertilizing Leiopelma hochstetteri (family Leiopelmatidae). Cytochemistry of sperm nuclei in the advanced, externally fertilizing neobatrachian frogs Crinia signifera and C. deserticola (family Myobatrachidae) indicates that they have reverted to H type SNBPs. This is also known to be the case in externally fertilizing Rana (family Ranidae) and Silurana, a subgenus of Xenopus (family Pipidae). Such a trend, from PL/P type SNBPs in two archeobatrachians to sporadic reversions to H type in more advanced frogs, parallels the ultrastructural simplification from complex A. truei introsperm to neobatrachian aquasperm that Jamieson et al. (1993. Herpetologica 49:52-65) attribute as a secondary reversion to external fertilization.

Animals↗
PubMed1975

[Incorporation of a 131-iodine-deoxycytidine monophosphate protamine complex into the DNA of tumor-bearing rats following partial synchronization with hydroxyurea].

The incorporation of 131-Iodo-deoxyuridine in rat tumours can be increased by partial synchronisation with hydroxyurea. The reported investigation was carried out to determine whether the incorporation could be further increased by using a basic 131-Iodo-deoxycytidine-monophosphate-protamine complex as a depot of Iodo-deoxyuridine. It was shown that the incorporation observed after synchronisation could be increased by using this complex (non-synchronized tumours 1,46% retention, synchronized tumours 2,28% retention; measured 4 hour after the final injection of hydroxyurea) whereas in a control group injected with 131-Iodo-deoxycytidine-monophosphate alone, only a small increase was observed. The large increase in activity in the liver and in the spleen (liver: non-synchronized 2,76%, synchronized 2,79% retention; spleen: non-synchronized 3,00, synchronized 3,80% retention; measured 4 hours after final injection of hydroxyurea) which is observed after injection of the 131-Iodo-deoxycytidine-monophosphate-protamine complex renders it unsuitable for use in the scintigraphic detection of tumours. 131-Iodo-deoxyuridine is shown to be more suitable for this purpose.

Animals↗
PubMedDate not supplied

Cardiac surgery in patients with protamine allergy.

Intravenous administration of protamine is associated with risk of severe anaphylactic and anaphylactoid reactions. In this review the incidence, pathophysiology, clinical management, and strategies for prevention of protamine reactions are addressed.

Algorithms↗
PubMedDate not supplied

[Interaction of the nuclear proteins protamine and histone with charged bilayer membranes].

The interaction of nuclear proteins of protamine and histone with neutral and charged BLM was studied. Anion and cation detergents were used to create the surface charge. The surface density of charges in BLM was comparable with that in biomembranes. Protamine and histone increased the electroconductivity of negatively charged BLM for anions and cations correspondingly. It is suggested that the surface charge of the membrane may influence the ion transport directly and indirectly due to the interaction of the membrane structures with charged proteins present in the surrounding medium.

Histones↗
PubMed2002

Cytochemical studies on histone-type and protamine-type proteins during spermiogenesis in Chara vulgaris and Chara tomentosa.

Comparative studies concerning detection of histone-type and protamine-type proteins were carried out on Chara species (C. vulgaris, C. tomentosa). Analysis of antheridia during spermiogenesis (stages I-X) of both Charta species showed very similar staining patterns obtained after reactions revealing the examined proteins. Cytochemical studies showed a replacement of lysine-rich histone proteins by more basic arginine-rich ones during medium spermiogenesis (st. VI-VIII) in two Charta species, while late spermiogenesis (st. IX) and mature spermatozoids (st. X) were characterised by the presence of protamine-like proteins only.

Animals↗
PubMed2002

[Protamine allergy in heart surgery].

A 68-year-old woman was admitted for open heart surgery. She had no history of allergy, but had suffered acute heart failure after having received protamine twice. Possible predisposition to adverse reactions is discussed and ways of reducing adverse reactions to protamine are suggested.

Aged↗
PubMed1991

Cuttlefish spermatid-specific protein T. Molecular characterization of two variants T1 and T2, putative precursors of sperm protamine variants Sp1 and Sp2.

In cuttlefish, as in selachians and mammals, spermiogenesis is characterized by the double nuclear protein transition histones----intermediate protein (protein T)----protamine (protein Sp). The cuttlefish protein T, which consists of two structural variants phosphorylated at different degrees, is the first invertebrate spermatid-specific protein to be fully characterized and sequenced. The primary structures of these two variants were established from sequence analysis and mass spectrometric data of the proteins and their fragments. T1 and T2 are two highly related proteins of 78 and 77 residues, respectively, which differ only by four conservative substitutions, two inversions Ser in equilibrium with Arg, and the deletion of 1 residue of arginine in variant T2. The asymmetrical distribution of the hydrophobic and basic residues determines two well defined domains: an amino-terminal domain (residues 1-21) devoid of arginine and aromatic residues and containing all the aliphatic hydrophobic residues and a highly basic carboxyl-terminal domain (residues 22-77 or 78) that contains 77% of arginine, all the tyrosine residues, and most of the phosphorylated serine residues present in the protein. The complete structural identity of the basic carboxyl-terminal domain of spermatidal proteins T1 and T2 with the protamine variants Sp1 and Sp2 isolated from cuttlefish spermatozoa strongly suggests that T1 and T2 could be precursors of Sp1 and Sp2, respectively.

Amino Acid Sequence↗
PubMedDate not supplied

Rapid and precise whole blood protamine titration.

A rapid and precise whole blood protamine titration method was developed. The method uses azure A dye as the titration indicator and thereby replaces the tedious and time-consuming clotting assay with a facile colorimetric assay. The method provides the same accuracy in estimating the titration end-point, but allows the processing time to be shortened to that required by current clinical methods. The simplicity, flexibility, speed, and accuracy offered by the method, and the ability to use whole blood specimens for the measurements, should allow the method to be used by clinicians in the operating room or during a surgical procedure to estimate the adequate protamine dose required for heparin reversal.

Azure Stains↗
PubMedDate not supplied

[Amino acid composition, heterogeneity and antiheparin activity of protamine sulfate from the milt roe of the sturgeon Acipenser sturio].

The homogeneous preparation of protamine sulphate is obtained chromatographically and electrophoretically from milt roe of the sturgeon. Its amino acid composition and properties are studied. The methods to blockade the functional groups of protamine sulphate amino acids is used to investigate the possible mechanism of heparin inactivation.

Amino Acids↗
PubMedDate not supplied

[Intensification of the diabetogenic effect of alloxan by protamine sulfate].

Administration of protamine sulfate into circulation was shown to increase the diabetogenic effect of alloxan. Protamine sulfate bound endogenous heparin, as a result of which the diabetogenic factor caused more severe forms of experimental diabetes. At the same time, the diabetogenic factor exhibited distinctly higher activity during the heparin deficiency developed.

Alloxan↗
PubMed1988

Comparison of phosphorylation sites in protamines between protein kinase C and cAMP-dependent protein kinase.

Phosphorylation sites of protamines by protein kinase C and cAMP-dependent protein kinase (protein kinase A) were studied. Using clupeine Y1 as a substrate, protein kinase C phosphorylates both Ser and Thr residues, whereas protein kinase A phosphorylates only Ser residue(s). Protein kinase C phosphorylates all Ser and Thr residues of clupeine Y2 and Z, however protein kinase A phosphorylates mainly Ser9 and slightly Thr5 in clupeine Y2 and Ser6 and Ser10 in clupeine Z. These results suggest that protein kinase C recognizes more sites than those of protein kinase A and may participate in protamine phosphorylation in vivo.

Amino Acid Sequence↗
PubMed1988

An unusual cysteine-containing histone H1-like protein and two protamine-like proteins are the major nuclear proteins of the sperm of the bivalve mollusc Macoma nasuta.

The sperm-specific protamine-like (PL) components PL-I, PL-II, and PL-III from the sperm of the bent-nose clam Macoma nasuta have been isolated and characterized for the first time. These proteins coexist in the sperm nuclei with a small percentage of a full histone complement. All of them have a very similar amino acid composition, following what seems to be the general composition prototype for the class Bivalvia (Ausió, J. (1986) Comp. Biochem. Physiol. B Comp. Biochem. 85, 439-449). Nevertheless, they have different molecular weights (PL-I = 23,500, PL-II = 15,600, and PL-III = 7,900) as measured by sedimentation equilibrium in the analytical ultracentrifuge. Furthermore, the PL-I component shares common features with the proteins of the histone H1 family. Yet, it is very unusual, for it contains 2 cysteine residues that are located in the trypsin-resistant core of this protein. The protamine-like fraction PL-III exhibits intraspecific microheterogeneity which is reflected by the presence of two protein variants which most probably are the result of an allelic polymorphism.

Amino Acids↗
PubMed1978

Degradation of low-density lipoproteins (LDL) and LDL - protamine complexes by lysosomal protease.

Native LDL are degraded by the protease of the lysosomal extract but they are not sensitive to isolated cathepsin D. Protamine increases the sensitivity of LDL to the effect of lysosomal protease and makes them sensitive to the effect of cathepsin D. Degradation of LDL by lysosomal protease is most intensive between pH 4.0 and 4.5 but in case of LDL bound with protamine it is most intensive at pH 4.5--5.0.

Cathepsins↗
PubMed1983

Anticoagulant monitoring and neutralization during open heart surgery--a rapid method for measuring heparin and calculating safe reduced protamine doses.

Confident monitoring of heparin during cardiopulmonary bypass and subsequent neutralization by protamine has been hampered by the absence of an accurate, reproducible, rapid, simple, and specific assay for heparin. By using two new instruments in tandem, one of which produced 0.5 ml of plasma in 1 min and one which specifically measures heparin in 3-4 min, heparin levels are available in approximately 5 min. By performing heparin assays at a variety of intervals, it was demonstrated that 76% of patients receiving common doses of heparin during cardiopulmonary bypass may have plasma levels that are potentially too low. Minimum neutralizing doses of protamine may be calculated using the formula: (estimated blood volume + pump prime volume) X (plasma heparin level/100) X 1.1 + 50. These doses were nearly two-thirds of previous doses and were unassociated with increased bleeding, clotting, or clinically significant heparin rebound.

Biological Assay↗
PubMed1980

Characterization of a new potent heparin. 2nd communication: Chemical analysis of the carbohydrate content and determination of the biological activity of a new potent heparin preparation in vitro, using protamine neutralization and amidolytic methods for factor Xa and thrombin.

A new potent heparin preparation was further characterized for carbohydrate content and for biological activities in vitro using the protamine neutralization test and amidolytic methods for factor Xa and thrombin. The chemical analysis of the heparin preparations showed similar amounts of glucosamine and glucuronic acid as known for other heparin preparations. In protamine neutralization test the new heparin was 1.32 times more active than commercial heparin. The amidolytic method using chromogenic substrates S-2222 for factor Xa and S-2238 for thrombin demonstrated that the new heparin was also at least two times more effective than commercial heparin in increasing the rate of inactivation of these serin proteases through antithrombin III.

Animals↗