Spermatogenesis is a complex differentiation process under the hormonal control of the hypothalamic-pituitary axis. The CREM gene encodes activators and repressors of cAMP-mediated gene transcription. The transcript corresponding to the activator isoform CREMtau is found at high levels in pachytene spermatocytes onwards. The CREMtau protein, however, is present only in post-meiotic spermatids w...

By means of qualitative staining experiments the characteristic protein changes which occur during maturation of salmon sperm can be followed. It can be observed that the replacement of histone by protamine takes place after completion of meiosis during an advanced stage of spermiogenesis.

Degradation of insulin was studied in this work. Casein and protamine could obviously suppress degradation of insulin by intestinal enzymes, and could protect insulin from degradation by the mechanism of competition and combination with proteolysis enzyme. What is more, co-incubated with HP-beta-CD-casein or HP-beta-CD-protamine, most insulin was protected from degradation by intestinal enzymes...

Cardiac surgical case histories, collected over 4 years at Huntsville Hospital in Alabama, were reviewed for 2,293 patients. Patients were separated into two dosing groups for both heparin and protamine, hospital empirically dosed and Hemochron RxDx dosed. Review of the heparin dosing information found that incomplete data were collected for 47 patients, leaving 2,246 patients eligible to be ev...

PURPOSE To establish the optimal protocol of heparin administration during interventional neuroradiology. METHODS We assessed 100 cases of neuroangiography, including endovascular surgery, and measured activated coagulation time before and 5 minutes after heparin administration, and before and 5 minutes after protamine neutralization. In some cases actual heparin concentration was assayed usi...

The influence of extracytoplasmic proteases on the resistance of Escherichia coli to the antimicrobial peptide protamine was investigated by testing strains with deletions in the protease genes degP, ptr, and ompT. Only DeltaompT strains were hypersusceptible to protamine. This effect was abolished by plasmids carrying ompT. Both at low and at high Mg2+ concentrations, ompT+ strains cleared pro...

Fig. 1 . Effect of increasing amounts of protamine sulfate on the ace measurement of hepann in whole blood (1 USP unlt/mL) The protam,ne/hepann ratio is based on the assumption that 0.01 mg of protamine neutralizes 1 unIt of hepaiin. The measured hepaiin concentration is shown as a percent of anti-factor Xa activity relative to baseline (no added protamine) determined in each experiment. The re...

The presence of specific messenger RNAs in the nuclei of mature mammalian spermatozoa has been demonstrated by several independent laboratories. Others have suggested that various polymerases may also be active in mature spermatozoa. This has led to the notion that the 'sleeping' genome may not be so quiescent after all. The alternate use of somatic-like nucleosomal and haploid protamine packag...

In mammals, the maternal and the paternal genome are not functionally equivalent and are both required for embryonic and postnatal development. The genome is organised differently in the oocyte as compared to sperm, in which the DNA is tightly packaged with protamines rather than with histones. The requirement of both the parental genomes for normal development is a consequence of differential ...