Identification of a new truncated form and deamidation products of fibrinopeptide B released by thrombin from human fibrinogen

2006 ◽  
Vol 96 (09) ◽  
pp. 302-308 ◽  
Author(s):  
Barbara Cardinali ◽  
Gianluca Damonte ◽  
Luca Melone ◽  
Annalisa Salis ◽  
Francesca Tosetti ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Molecular Mass ◽  
Aspartic Acid ◽  
Pyroglutamic Acid ◽  
Truncated Form ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Human Fibrinogen ◽  
Ms Analysis ◽  
Capillary Electrophoretic

SummaryQuantification of fibrinopeptides release is widely used to investigate fibrinogen activation, and standard chromatographic or capillary electrophoretic procedures are readily available. However, in the analyses of fibrinopeptide mixtures derived from the action of thrombin on human fibrinogen, a few unidentified peaks are usually present. The composition of these peaks was studied by reverse-phase HPLC/MS, revealing a single major anomalous peptide having a molecular mass of 1384.4. A further MS/MS analysis allowed the identification of this form, as a Nterminally truncated fibrinopeptideB (fpB) lacking the first two residues (pyroglutamic acid and glycine). This previously unidentified, relatively low-abundance form (∼7%) has been found consistently in our fibrinopeptides preparations, and analysis of the parent Bβ-chain suggest that it is likely present in circulating fibrinogen. In addition, deamidated forms of all fpB species (including desArgB), resulting from the conversion of asparagine to aspartic acid, were also identified. Overall, these previously unreported forms constitute a substantial amount of fpB (up to ∼17% of the total), and should be taken into account for a reliable quantitative analysis of fpB release.

A Synthetic Analog of Fibrinogen α27–50 Is an Inhibitor of Thrombin

1991 ◽  
Vol 65 (02) ◽  
pp. 165-168 ◽  
Author(s):  
Cameron G Binnie ◽  
Susan T Lord
Keyword(s):  
Active Site ◽  
Synthetic Peptide ◽  
Synthetic Analog ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Human Fibrinogen ◽  
Thrombin Inhibition ◽  
Thrombin Cleavage ◽  
Covalently Linked ◽  
Low Ionic Strength

SummaryBinding of the synthetic peptide AAKDSDWPEASDEDWNYKAPSGAR, a fibrinogen α27–50 analog, to thrombin was studied by inhibition assays and affinity chromatography. Peptide α27–50 corresponds to a segment of human fibrinogen downstream from the thrombin cleavage site, with cysteine residues at positions 28, 36, 45 and 49 replaced by alanine. The peptide inhibited clotting of fibrinogen with an inhibition constant of 190–400 μM. Cleavage of fibrinopeptides A and B was inhibited by the peptide and the peptide was competitive with fibrinogen for thrombin. Inhibition of the small substrate tosyl-Gly-Pro-Arg-p-nitroaniline was not observed indicating that the peptide did not block the active site of the enzyme. Peptide α27–50 that was covalently linked to Sepharose bound active siteinhibited thrombin at low ionic strength and was eluted at higher salt concentration. The peptide was not cleaved on overnight exposure to thrombin as determined by reverse phase HPLC. In summary, the peptide bound to, but was not a substrate for thrombin. These results suggest that this region of fibrinogen contributes to binding of thrombin.

scholarly journals Ontogenetic Change in the Venom of Mexican Black-Tailed Rattlesnakes (Crotalus molossus nigrescens)

Toxins ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 501 ◽  
Author(s):  
Miguel Borja ◽  
Edgar Neri-Castro ◽  
Rebeca Pérez-Morales ◽  
Jason Strickland ◽  
Roberto Ponce-López ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Snake Venom ◽  
Serine Proteinases ◽  
Ontogenetic Changes ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Venom Composition ◽  
Hemorrhagic Activity ◽  
Ecological Implications ◽  
Total Body

Ontogenetic changes in venom composition have important ecological implications due the relevance of venom in prey acquisition and defense. Additionally, intraspecific venom variation has direct medical consequences for the treatment of snakebite. However, ontogenetic changes are not well documented in most species. The Mexican Black-tailed Rattlesnake (Crotalus molossus nigrescens) is large-bodied and broadly distributed in Mexico. To document venom variation and test for ontogenetic changes in venom composition, we obtained venom samples from twenty-seven C. m. nigrescens with different total body lengths (TBL) from eight states in Mexico. The primary components in the venom were detected by reverse-phase HPLC, western blot, and mass spectrometry. In addition, we evaluated the biochemical (proteolytic, coagulant and fibrinogenolytic activities) and biological (LD50 and hemorrhagic activity) activities of the venoms. Finally, we tested for recognition and neutralization of Mexican antivenoms against venoms of juvenile and adult snakes. We detected clear ontogenetic venom variation in C. m. nigrescens. Venoms from younger snakes contained more crotamine-like myotoxins and snake venom serine proteinases than venoms from older snakes; however, an increase of snake venom metalloproteinases was detected in venoms of larger snakes. Venoms from juvenile snakes were, in general, more toxic and procoagulant than venoms from adults; however, adult venoms were more proteolytic. Most of the venoms analyzed were hemorrhagic. Importantly, Mexican antivenoms had difficulties recognizing low molecular mass proteins (<12 kDa) of venoms from both juvenile and adult snakes. The antivenoms did not neutralize the crotamine effect caused by the venom of juveniles. Thus, we suggest that Mexican antivenoms would have difficulty neutralizing some human envenomations and, therefore, it may be necessary improve the immunization mixture in Mexican antivenoms to account for low molecular mass proteins, like myotoxins.

Preparation and Characterization of NH2-Terminal Fibrinogen Bβ Fragments from N-DSK of Human Fibrinogen

1984 ◽  
Vol 51 (01) ◽  
pp. 016-021 ◽  
Author(s):  
S Birken ◽  
G Agosto ◽  
B Lahiri ◽  
R Canfield
Keyword(s):  
High Performance ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Reverse Phase ◽  
Human Fibrinogen ◽  
Human Volunteers ◽  
Cnbr Cleavage ◽  
Two Peaks

SummaryIn order to investigate the early release of NH2-terminal plasmic fragments from the Bβ chain of fibrinogen, substantial quantities of Bβ 1-42 and Bβ 1-21 are required as immunogens, as radioimmunoassay standards and for infusion into human volunteers to determine the half-lives of these peptides. Towards this end methods that employ selective proteolytic cleavage of these fragments from fibrinogen have been developed. Both the N-DSK fragment, produced by CNBr cleavage of fibrinogen, and Bβ 1-118 were employed as substrates for plasmin with the finding of higher yields from N-DSK. Bβ 1-42 and Bβ 1-21 were purified by gel filtration and ion-exchange chromatography on SP-Sephadex using volatile buffers. When the purified preparation of Bβ 1-42 was chromatographed on reverse-phase high performance liquid chromatography, two peaks of identical amino acid composition were separated, presumably due either to pyroglutamate or to amide differences.

Understanding Process Variables and their Interactions for Maximizing Production of Artemisinin Derivative Artemether (Anti-Malarial Drug) Through Cunninghamella echinulata var elegans at 5 L Bioreactor Level

2019 ◽  
Vol 15 (4) ◽  
pp. 442-452
Author(s):  
Kashyap Kumar Dubey ◽  
Punit Kumar
Keyword(s):  
Experimental Finding ◽  
Culture Broth ◽  
Quadratic Model ◽  
Optimum Conditions ◽  
Reverse Phase Hplc ◽  
Polar Solvents ◽  
Reverse Phase ◽  
Experimental Conditions ◽  
Cunninghamella Echinulata ◽  
Life Threatening

Background: Malaria is one of the life threatening diseases which is caused by Plasmodium sp. of protozoa and uses Anopheles mosquitos as vector. Plasmodium vivax and Plasmodium falciparum are common form of malaria parasite. Artemisinin is reported for its antimalarial activities and Artemether which is a methyl ether derivative of Artemisinin, has been found effective against P. falciparum. Methods: In the present study, bioconversion of Artemisinin into Artemether was carried out experimentally and the statistical tools like experimental factorial design and Response Surface Methodology were used to find optimal conditions (concentration of Artemisinin, age of inoculum, temperature & pH) using Cunninghamella echinulata var. elegans. Experimental conditions for maximum product recovery from culture broth were also optimized using various polar and non-polar solvents for extraction. Artemether purity was analyzed by reverse-phase HPLC. Experimental data was fitted in a quadratic model and effect of various parameters was analyzed. Results: It was found that bioconversion of Artemisinin into Artemether is growth associated process. It was observed that molasses used as carbon source supported production of Artemether to 3.4g/L. The biomass and oxygen are key element affecting of bioconversion of Artemisinin into Artemether such as higher dissolved oxygen reduced the Artemether bioconversion. The highest bioconversion of Artemisinin into Artemether was obtained at temperature 25.5oC, 5g/L concentration of Artemisinin, at age of inoculum of 44.5 h and at pH 6.0. Model suggested the highest bioconversion of Artemisinin into Artemether was 54% at shake flask level which was near about experimental finding. An optimal condition for bioconversion was also analyzed and 64% bioconversion was obtained in 5L bioreactor. Conclusion: The outcomes of the study provided optimum conditions for bioconversion of Artemisinin into Artemether.

scholarly journals Orphan Designation and Cisplatin/Hyaluronan Complex in an Intracavitary Film for Malignant Mesothelioma

Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 362
Author(s):  
Sabrina Banella ◽  
Eride Quarta ◽  
Paolo Colombo ◽  
Fabio Sonvico ◽  
Antonella Pagnoni ◽  
...  
Keyword(s):  
Sodium Hyaluronate ◽  
Chloride Ions ◽  
Complete Resection ◽  
Size Exclusion ◽  
European Medicines Agency ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Pharmaceutical Development ◽  
Film Forming ◽  
Exclusion Chromatography

Pleural mesothelioma is a lung diffuse tumor, whose complete resection is unlikely. Consequently, metastases reappear where the primary tumor was removed. This paper illustrates the orphan medicine designation procedure of an intracavitary cisplatin film and related pharmaceutical development aspects requested by the European Medicines Agency (EMA) in its Scientific Advice. Since cisplatin pharmacokinetics from the implanted film in sheep resulted substantially modified compared to intravenous administration, the formation of a cisplatin/hyaluronan complex had been hypothesized. Here, the interaction between sodium hyaluronate (NaHA) and cisplatin (CisPt) was demonstrated. Size exclusion chromatography qualitatively evidenced the complex in the film-forming mixture, only showing the NaHA peak. Atomic absorption spectroscopy of the corresponding fraction revealed platinum, confirming the interaction. Reverse phase HPLC quantified about 5% free cisplatin in the film-forming mixture, indirectly meaning that 95% was complexed. Finally, a study of CisPt release from the film assessed how CisPt/NaHA complex affected drug availability. In water, a medium without chloride ions, there was no release and the film remained intact for 48 h and longer, whereas the placebo film dissolved in 15 min. In 0.9% NaCl medium, the film became more soluble, dissolving within 3–4 h. However, cisplatin release was still controlled by the existing complex in solution until chloride ions displaced it. While the film modified its dissolution with aging, CisPt release remained unaffected (90% released in 48 h).

scholarly journals A A RAPID AND SENSITIVE RP-HPLC METHOD FOR THE QUANTITATIVE ANALYSIS OF EMPAGLIFLOZIN IN BULK AND PHARMACEUTICAL DOSAGE FORM

2019 ◽  
pp. 60-65
Author(s):  
MADHURIMA BASAK ◽  
Santhosh Reddy Gouru ◽  
Animesh Bera ◽  
Krishna veni Nagappan
Keyword(s):  
Quantitative Analysis ◽  
High Performance ◽  
Dosage Form ◽  
Limit Of Detection ◽  
Hplc Method ◽  
Reverse Phase ◽  
Pharmaceutical Dosage Form ◽  
Rp Hplc ◽  
Limit Of Quantitation ◽  
Bulk Drug

Objective: The present study aims at developing an accurate precise, rapid and sensitive Reverse Phase High-Performance Liquid Chromatography (RP-HPLC) method for assessing Empagliflozin in bulk drug and in the pharmaceutical dosage form. Methods: The proposed method employs a Reverse Phase Shim Pack C18 column (250 mm × 4.6 mm id; 5 µm) using a mobile phase comprising of acetonitrile and water in the ratio of 60:40 v/v flushed at a flow rate of 1 ml/min. The eluents were monitored at 223 nm. Results: Empagliflozin was eluted at a retention time of 5.417 min and established a co-relation co-efficient (R2>0.999) over a concentration ranging from 0.0495-100µg/ml. Percentage recovery was obtained between 98-102% which indicated that the method is accurate. The Limit of Detection (LOD) and Limit of Quantitation (LOQ) were found at 0.0125µg/ml and 0.0495µg/ml, respectively. Conclusion: An RP-HPLC method which was relatively simple, accurate, rapid and precise was developed and its validation was performed for the quantitative analysis of empagliflozin in bulk and tablet dosage form (10 and 25 mg) in accordance to International Conference of Harmonization (ICH) Q2 (R1) guidelines. The proposed method may aid in routinely analyzing empagliflozin in pharmaceuticals.

Quantitation of Amiodarone and Desethylamiodarone from Blood Serum and Myocardium Using Reverse Phase HPLC

1987 ◽  
Vol 10 (12) ◽  
pp. 2625-2637 ◽  
Author(s):  
J. Alan Menius ◽  
D. James Schumacher ◽  
Emily A. Hull-ryde ◽  
Cyril Y. Leung ◽  
Robin G. Cummings ◽  
...  
Keyword(s):  
Blood Serum ◽  
Reverse Phase Hplc ◽  
Reverse Phase
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