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At least 1,099 records · Page 61Linked to original sources
PubMed1979

The treatment of postperfusion bleeding using epsilon-aminocaproic acid, cryoprecipitate, fresh-frozen plasma, and protamine sulfate.

The evaluation of excessive hemorrhage was carried out in 774 patients after cardiopulmonary bypass. Excessive hemorrhage was defined in any adult patient as chest tube drainage of more than 600 ml within the first eight hours after operation. Using the prothrombin time, partial thromboplastin time, fibrinogen level, and tri-F titer tests, it was possible to differentiate medical from surgical bleeding. Hyperfibrinolytic bleeding was the most frequently identifiable coagulation disorder and occurred in 159 patients (20%). All these patients were successfully treated with Amicar (epsilon-aminocaproic acid) alone, or with Amicar supplemented with cryoprecipitate or fresh-frozen plasma. Three patients (0.4%) were noted to have residual heparin and required additional protamine sulfate. Five patients (0.6%) had normal coagulation studies and required immediate reexploration. The overall blood consumption per patient was 2.1 units of packed cells. Whole blood and platelets were not used.

Aminocaproates↗
PubMed1985

Distribution of negative charges of rat brain synaptosomes established by means of protamine-ferritin conjugate.

The negative electric charges on the synaptosomes from rat cerebral cortex were studied by means of protamine-ferritin conjugate. The synaptic vesicles in some synaptosomes were heavily labelled with the positively charged conjugate. The synaptosomal membranes including presynaptic and postsynaptic membranes were also stained but in a lesser degree. It was established that the major dense line and the intraperiod line of myelin contaminants were labelled, too.

Animals↗
PubMed1988

Fluorescein mercuric acetate as a dye for fluorescence and electron microscope detection of -SH groups in mouse sperm protamines: a critical evaluation.

Fluorescein Mercuric Acetate (FMA), a specific fluorescent dye for thiols, was tested as a possible reagent for the ultrastructural detection of -SH groups in sperm chromatin protamines. It was shown that FMA may be profitably used for staining at electron microscopy the chromatin -SH groups of caput epididymidis spermatozoa. Like other mercury compounds, FMA proved to be unstable under the electron beam; therefore the use of low beam intensity, and cooling of the specimens are recommended. The main advantages of this staining method are the relatively lower toxicity of FMA, compared to other organic mercurials, and the opportunity to compare the fluorescence patterns on semithin sections with the corresponding ultrastructural findings on thin sections.

Animals↗
PubMed2003

Intravesical protamine sulfate and potassium chloride as a model for bladder hyperactivity.

OBJECTIVES: An acute animal model for hyperactive bladder in rats was developed using intravesical infusion of protamine sulfate (PS), an agent thought to break down urothelial barrier function, and physiologic concentrations of potassium chloride (KCl). METHODS: Continuous cystometrograms (CMGs) were performed in urethane-anesthetized female rats by filling the bladder (0.04 mL/min) with normal saline followed by intravesical infusion of a test solution consisting of either KCl (100 or 500 mM) or PS (10 or 30 mg/mL) for 60 minutes. Subsequently, the 10 mg/mL PS-treated animals were infused intravesically with 100, 300, or 500 mM KCl. Some animals were pretreated with capsaicin (125 mg/kg subcutaneously) 4 days before the experiments. RESULTS: Unlike KCl (100 or 500 mM) or a low concentration of PS (10 mg/mL) alone, the intravesical administration of a high concentration of PS (30 mg/mL) produced irritative effects with a decreased intercontraction interval (by 80.6%). After infusion of a low concentration of PS, infusion of 300 or 500 mM KCl produced irritative effects (intercontraction interval decreased by 76.9% or 82.9%, respectively). The onset of irritation occurred more rapidly after 500 mM KCl (10 to 15 minutes) than after 300 mM KCl (20 to 30 minutes). Capsaicin pretreatment delayed the onset (approximately 60 minutes) and reduced the magnitude (intercontraction interval decreased by 35.5%) of irritative effects. CONCLUSIONS: Intravesical administration of KCl after PS treatment activates capsaicin-sensitive afferents and detrusor muscle and presumably capsaicin-resistant afferents. Modest, noncytotoxic affronts to urothelial barrier function can result in dramatic irritative responses. This model may be useful in the study of bladder irritation and hyperactivity.

Administration, Intravesical↗
PubMed1985

Tandem repeats of a specific alternating purine-pyrimidine DNA sequence adjacent to protamine genes in the rainbow trout that can exist in the Z form.

We have located an extensive (AC)n-rich but specific sequence downstream of three rainbow trout protamine genes. Although sharing considerable sequence homology, including a perfectly conserved 46 base pair repeat, the sequences exhibit a regular heterogeneity in the length of the (AC)n-rich tracts. Radioimmunoassay experiments, S1 nuclease sensitivity studies, two-dimensional electrophoretic analysis, and immunoelectron microscopy studies have been used to determine if the region could assume a Z DNA conformation. It was found that, in a supercoiled plasmid, the (AC)n-rich region has the ability to attain the Z DNA conformation under physiological conditions.

Animals↗
PubMed1985

General method for isolation of DNA sequences that interact with specific nuclear proteins in chromosomes: binding of the high mobility group protein HMG-T to a subset of the protamine gene family.

A general method is described for the isolation of the DNA with which specific nuclear proteins interact in chromosomes. This method is based on the covalent photo-cross-linking of nuclear proteins to the DNA sequences, to which they normally bind, by means of irradiation with UV light and the selective retrieval of specific subsets of protein-DNA adducts by using specific antibodies. The application of this procedure to isolate the DNA sequences with which the trout high mobility group protein (HMG-T) interacts has shown that in trout liver this protein associates specifically with DNA sequences in proximity to a subset of the family of protamine genes but not with the histone or vitellogenin genes. From these observations, it appears that the HMG-T protein may be associated with inactive gene sequences.

Animals↗
PubMedDate not supplied

Protamine assembled in multilayers on colloidal particles can be exchanged and released.

Biocomposite thin films assembled on colloidal particles by means of layer-by-layer adsorption have been suggested as drug carriers and diagnostic devices. Protamine (PRM)/dextransulfate (DXS) and protamine/bovine serum albumine (BSA) multilayers were fabricated on colloidal silica and subsequently investigated by means of fluorescence activated cell sorting (FACS) and microelectrophoresis. Fluorescein labeled polyelectrolytes were embedded at different positions in the multilayers as a marker for layer growth. FACS showed that PRM and DXS formed regular growing stable multilayers, yet adsorbed PRM can be nevertheless exchanged with PRM in solution during layer formation and also after the multilayer formation has been completed. Up to 90% of the PRM pool was available for exchange. PRM together with BSA as demonstrated by SFM did not form multilayers under the applied conditions although the zeta-potential, commonly used as an indicator for stepwise adsorption, observed characteristic alternations. The capability of bound PRM to exchange with PRM in solution is attributed to its relatively small size. The demonstrated exchange may have importance in designing multilayers with smart release features. Furthermore, FACS proved to be a rather suitable means to quantify the aggregation behavior during coating and washing. Singulets, doublets, triplets, and aggregates of higher order could be clearly resolved. The aggregation of particles coated with PRM/DXS layers was higher than that of silica particles coated with PAH/PSS layers. In the first case about 50% of all recorded events are attributed to aggregats, while the PAH/PSS coating produced only about 10% aggregates.

Adsorption↗
PubMed2000

Induction of a secondary structure in the N-terminal pentadecapeptide of human protamine HP2 through Ni(II) coordination. An NMR study.

A solution structure of the Ni(II) complex with the N-terminal pentadecapeptide of human protamine HP2 (HP2(1)(-)(15)) was elucidated with the use of a range of one- and two-dimensional (1)H NMR techniques and molecular modeling. A striking double-loop conformation was found, exhibiting the interactions of the aromatic ring of the Tyr(8) residue with the Ni(II) coordination site at Arg(1), Thr(2), and His(3) residues and the side chain of the Arg(15) residue. In such a conformation, a tendency was found for all five positively charged arginine side chains to locate on one side of the molecule, making possible efficient contacts with the DNA double helix. These structural features, induced indirectly by Ni(II) coordination, are discussed in terms of a possible physiological function of the N-terminus of HP2 as a metal-binding site.

Amino Acid Sequence↗
PubMed1997

Binding of nickel(II) and copper(II) to the N-terminal sequence of human protamine HP2.

A potentiometric and spectroscopic (UV/vis and CD) study of Cu(II) and Ni(II) binding to the N-terminal pentadecapeptide of human protamine HP2 (HP2(1-15)) was performed. The results indicate that the N-terminal tripeptide motif Arg-Thr-His is the exclusive binding site for both metal ions at a metal to HP2(1-15) molar ratio not higher than 1. The very high value of protonation-corrected stability constant (log *K) for Ni(II)-HP2(1-15) complex, -19.29, indicates that HP2 has the potential to sequester Ni(II) from other peptide and protein carriers, including albumin. The same is likely for Cu(II) (log *K = -13.13). The CD spectra of Cu(II) and Ni(II) complexes of HP2(1-15) indicate that the N-terminal metal binding affects the overall conformation of the peptide that, in turn, may alter interaction of HP2 with DNA. These results imply HP2 as a likely target for the toxic metals Ni(II) and Cu(II).

Amino Acid Sequence↗
PubMed1997

Mediation of oxidative DNA damage by nickel(II) and copper(II) complexes with the N-terminal sequence of human protamine HP2.

The potential of Ni(II) and Cu(II) complexes with Arg-Thr-His-Gly-Gln-Ser-His-Tyr-Arg-Arg-Arg-His-Cys-Ser-Arg-amide (HP2(1-15)), a peptide modeling the N-terminal amino acid sequence of human protamine HP2, to mediate oxidative DNA damage was studied by measurements of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) generation from 2'-deoxyguanosine (dG) and calf thymus DNA and by formation of double-strand breaks in calf thymus DNA. The concentrations of reagents were 0.1 mM dG and the metal-HP2(1-15) complex, 1 mM H2O2, 1.5 mM DNA (per phosphate group), 100 mM phosphate buffer, pH 7.4, ambient O2. Samples were incubated at 37 degrees C for 16-24 h. The Cu(II)-HP2(1-15) complex was found to be an effective promoter of the formation of 8-oxo-dG from both dG and DNA with ambient O2 (approximately 13- and 3-fold increase versus the oxidant alone, respectively) and H2O2 (approximately 25-fold increase in either case). The Ni(II)-HP2(1-15) complex was ineffective with O2 versus 8-oxo-dG production from both substrates but markedly enhanced the attack of H2O2 on dG and DNA (approximately 5-fold increase of 8-oxo-dG production in either case). Both Cu(II)- and Ni(II)-HP2(1-15) equally promoted double-strand scission by H2O2 in calf thymus DNA. The promotion by the complexes of dG and DNA oxidation with H2O2 was accompanied by oxidative damage to the complexes themselves, consisting of decreasing contents of their His (to approximately 50% of control in either complex) and especially Tyr (down to 48% of control in Cu(II)- and 19% in Ni(II)-HP2[1-15]) residues, as well as appearance of aspartic acid, the known oxidation product of His residues in peptides (up to 22% vs Gly for Cu(II)- and 10% for Ni(II)-HP2(1-15)). The above results provide a novel chemical mechanism of Cu(II) and Ni(II) toxicity and may have wide implications for reproductive and transgenerational effects of metal exposure.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2000

Nuclear transport of oligonucleotides in HepG2-cells mediated by protamine sulfate and negatively charged liposomes.

PURPOSE: The aim of this study was to characterize the intracellular fate and nuclear uptake kinetics of oligonucleotides (ON) that were complexed with protamine sulfate (PS) and negatively charged liposomes at different ratios of ON to PS. METHODS: Double-fluorescence labelling of ON and liposomal lipid was applied to simultaneously monitor the interaction as well as the individual fate of active agent and carrier upon intracellular delivery using confocal laser scanning microscopy (CLSM). A DNA-analogue of a 68-mer intramolecular double-stranded RNA:DNA-hybridoligonucleotide (chimeraplasts) with unmodified phosphate backbone was employed. This construct was condensed with PS and coated with a liposomal formulation (AVE-3 = artificial viral envelope). RESULTS: PS-ON complexes and AVE -3-coated complexes with a defined composition were very effective in nuclear transport of ON for a ON:PS charge ratio of 1:3. Nucleus:cytosol fluorescence ratios peaked at about 10 hrs and started to decrease again at 21 hrs. CONCLUSIONS: AVE associates with PS-condensed ON, and this complex is able to be taken up by cells and to deliver ON to the nucleus. PS-ON complexes are released from the liposomal formulation, mainly as an extranuclear enzymatic degradation of the liposomal phospholipids. The results of the kinetic analysis can be used to optimize transfection protocols with ON in HepG2 cells.

Anions↗
PubMed2004

Encapsulation of catalase in polyelectrolyte microspheres composed of melamine formaldehyde, dextran sulfate, and protamine.

Immobilization of catalase (molecular weight 240,000 daltons) in polyelectrolyte microspheres was studied. The microspheres were obtained by alternating adsorption of dextran sulfate and protamine on commercially available melamine formaldehyde cores followed by the core hydrolysis at pH 1.7. As the interior of the microspheres was filled with homogeneous matrix, the catalase distribution inside the microspheres was uniform. The quantity of entrapped catalase was dependent on the initial concentration of the enzyme and pH of solution, and the peak value was 10(8)-10(9) molecules per microsphere. It was demonstrated that catalase was entrapped in the microspheres via electrostatic and hydrophobic interactions. The catalase activity inside the microspheres increased as the quantity of enzyme decreased, which was due to the switch between diffusion and kinetic regimes of the enzymatic reaction. The microspheres could be applied for separation and concentration of high molecular weight proteins.

Catalase↗
PubMed1987

The enhancement of aminonucleoside nephrosis by the co-administration of protamine.

An experimental model of focal segmental glomerular sclerosis (FSGS) was developed in rats by the combined administration of puromycin-aminonucleoside (AMNS) and protamine sulfate (PS). Male Sprague-Dawley rats, uninephrectomized three weeks before, received daily injections of subcutaneous AMNS (1 mg/100 g body wt) and intravenous PS (2 separated doses of 2.5 mg/100 g body wt) for four days. The series of injections were repeated another three times at 10 day intervals. The animals were sacrificed on days 24, 52, and 80. They developed nephrotic syndrome and finally renal failure. The time-course curve of creatinine clearance dropped and showed significant difference (P less than 0.01) from that of each control group, such as, AMNS alone, PS alone or saline injected. Their glomeruli showed changes of progressive FSGS. The ultrastructural studies in the initial stage revealed significant lack of particles of perfused ruthenium red on the lamina rara externa and marked changes in epithelial cell cytoplasm. Therefore, it is suggested that the administration of PS enhances the toxicity of AMNS on the glomerulus and readily produces progressive FSGS in rats resulting in the end-stage renal disease.

Animals↗
PubMed2004

In vivo efficacy of folate-targeted lipid-protamine-DNA (LPD-PEG-Folate) complexes in an immunocompetent syngeneic model for breast adenocarcinoma.

Gene therapy utilizing lipid-based delivery systems holds tremendous promise for the treatment of cancer. However, due to the potential adverse inflammatory and/or immune effects upon systemic administration, treatments thus far have been predominantly limited to intratumoral or regional treatment. Previous studies from our group have demonstrated the antitumor efficacy of systemically administered, folate-targeted, lipid-protamine-DNA complexes (LPD-PEG-Folate) against breast cancer using an immunodeficient xenogenic murine model. In the current study, the antitumor efficacy of LPD-PEG-Folate in a syngeneic, immune competent, murine model of breast cancer was examined. In this model, the potential inflammatory or immune responses and their effects on systemic delivery can be addressed. The 410.4 murine breast adenocarcinoma cell line was initially evaluated in vitro for its interactions with LPD-PEG-Folate and control LPD-PEG formulations. Utilizing fluorescently labeled formulations and fluorescence-activated cell sorting (FACS) analysis, a 1.6-fold enhancement of binding and internalization of LPD-PEG-Folate over LPD-PEG formulations was observed, suggestive of specific receptor interaction. Increased binding was manifested as 5-26-fold increases in luciferase gene expression in 410.4 cell transfection when comparing LPD-PEG-Folate to LPD-PEG. Moreover, in vivo treatment of 410.4 breast tumors in BALB/c mice with i.v. injected LPD-PEG-Folate delivering the HSV-1 thymidine kinase (TK) gene, in combination with gancyclovir treatment, resulted in a significant reduction in mean tumor volume (260.1 mm3) compared to the LPD-PEG-TK (914.1 mm3), as well as the vehicle (749.7 mm3) and untreated (825.3 mm3) control groups (day 25, P<.019). In addition to a reduced tumor volume, LPD-PEG-Folate-TK treatment also increased median survival from 25 days in the nontargeted LPD-PEG-TK groups to 31 days (P=.0011), which correlated with the termination of treatment. Together, these results demonstrate that in the context of a fully functional immune system, LPD-PEG-Folate-TK treatment possesses significant specific antitumor efficacy and the potential for further preclinical development.

Adenocarcinoma↗
PubMed2002

Basal-bolus insulin therapy in Type 1 diabetes: comparative study of pre-meal administration of a fixed mixture of insulin lispro (50%) and neutral protamine lispro (50%) with human soluble insulin.

AIMS: To ascertain whether pre-meal administration of 50% insulin lispro and 50% neutral protamine lispro (NPL), given as a fixed mixture (Humalog Mix50, human soluble (regular) insulin as a basal-bolus regimen in people with Type 1 diabetes. Both regimens included bedtime human isophane (NPH) insulin. METHODS: This was a multinational, multicentre, randomized, open-label, two-period crossover comparison of two insulin treatments for two 12-week periods in 109 patients with Type 1 diabetes. The protocol provided preliminary evaluations of dose requirements and recommendations for insulin dose adjustment when switching regimens on the basis of blood glucose (BG) values. Eight-point BG profiles, frequency of hypoglycaemia, HbA1c, insulin dose, time of injection, and frequency of snacking were assessed during each treatment. RESULTS: Total daily insulin dose was similar for both treatments, but the total pre-meal doses were higher (P < 0.001) and the bedtime dose of isophane was lower (P < 0.001) with Mix50. The pre-meal dose before breakfast and lunch, although statistically different (P = 0.006 and P < 0.001, respectively), was of similar magnitude, but the pre-evening meal dose was higher with Mix50 (P < 0.001). Median (interquartile range) time of insulin injection before meals was: Mix50 4.2 (25th percentile = 1.0; 75th percentile = 6.3) min, human soluble insulin 24.6 (25th percentile = 16.6; 75th percentile = 30.0) min. Pre-meal and bedtime BG concentrations did not differ between treatments. The BG 2 h after the evening meal was lower with Mix50 (8.40 +/- 2.95 mmol/l vs. 9.60 +/- 3.47 mmol/l) (P = 0.049). BG after breakfast and lunch, mean HbA1c, frequency of hypoglycaemia, frequency of snacks, and body weight were not different. CONCLUSION: The use of Mix50 in a basal-bolus regimen achieved similar control of pre-meal BG to human soluble insulin, and overall glycaemic control and hypoglycaemia risk were equivalent. This suggests that Mix50 can provide an adequate supply of insulin to control BG between meals while providing the convenience of injecting immediately before meals.

Adult↗
PubMedDate not supplied

A study on the erythrocyte aggregating properties of polybrene and protamine sulphate.

By observing the aggregation of erythrocytes in protamine sulphate or Polybrene it is possible to predict MN phenotypes with 97 per cent accuracy. It is probable that one factor influencing aggregation is the relative site density of a receptor common to both M and N antigen structures although other nondiscriminating receptor sites on a lower layer of sialic acid are possible also involved.

Acetylation↗
PubMed2000

Local anticoagulation of the extracorporeal circuit with heparin and subsequent neutralization with protamine during immunoadsorption.

A regimen of local anticoagulation of an immunoadsorption device was studied. The extracorporeal circuit was anticoagulated with citrate (5.5%) and a continuous infusion of heparin (2,000 U/h or 1,500 U/h), which was neutralized by a continuous infusion of protamine chloride (75% of the heparin dose) before reinfusion in 23 patients treated with low-density lipoprotein or immunoglobulin apheresis. Sufficient anticoagulation of the extracorporeal circuit was obtained (activated partial thromboplastin time [APTT] > 180 seconds; thrombin time [TT] > 120 seconds; anti-Xa activity, 1.05 +/- 0.21 U/mL) during the entire treatment of 190 minutes, whereas coagulation parameters in the patients' blood stayed within the normal range. In a control group without heparin neutralization, full systemic anticoagulation of the patients occurred (APTT, 157.8 +/- 30.6 seconds; TT, 119.8 +/- 0.4 seconds; anti-Xa activity, 0.88 +/- 0.21 U/mL). No side effects or clotting of the system were observed. Our data show that this regimen of local anticoagulation is a safe protocol for extracorporeal circulation without exposing the patients to anticoagulants.

Adult↗