Direct Analysis of Plasma Fibrinogen-Derived Fibrinopeptides by High Performance Liquid Chromatography: Investigation of Aα-Chain N-Terminal Heterogeneity

1986 ◽  
Vol 56 (02) ◽  
pp. 193-197 ◽  
Author(s):  
Christopher Southan ◽  
Elizabeth Thompson ◽  
David A Lane

SummaryFibrinopeptide A (FPA), released from the fibrinogen Aa-chain by thrombin, can be resolved by high-performance liquid chromatography (HPLC) into three forms, the intact peptide (A), a modified peptide phosphorylated at the serine in position 3 (AP), and an N-terminally degraded form (AY). A new method has been developed, using HPLC, that allows direct measurement of the proportions of AP, A, and AY released by thrombin from fibrinogen in plasma samples of 200 ul or less. The method was used to examine variations in the proportions of AP and AY expressed as a % of total FPA in a number of patient and control groups. The mean percentages of AP and AY of plasma fibrinogen were found to be 21.7 and 14.2%, respectively, in normal laboratory controls. In older, apparently normal, individuals these figures were 27.0 and 15.5%, respectively. Cord plasma exhibited very high AP and slightly reduced AY levels (41.6 and 12.4%, respectively) compared with normal adults. Patients with liver failure had low AP levels and high AY levels (11.6 and 21.1%, respectively). Patients, recovering from major surgery or acute thrombotic stroke showed an acute-phase rise in fibrinogen level that was accompanied by an increase in AP and variable reduction in AY. Incubation of heparinized whole blood for 8 days in vitro demonstrated a gradual decrease in the proportion of AP and increase in AY of plasma fibrinogen. These results provide some support for the idea that an increased “aging” of fibrinogen in the circulation may result in a decrease in the AP content of fibrinogen accompanied by a more variable increase in AY.

Author(s):  
Mariola Dreger ◽  
Katarzyna Seidler-Łożykowska ◽  
Milena Szalata ◽  
Artur Adamczak ◽  
Karolina Wielgus

AbstractThe purpose of the study was to evaluate Chamerion angustifolium (L.) Holub genotypes for preliminary selection and further breeding programs aimed at obtaining a suitable industrial form for the pharmaceutical applications. Clonally propagated plants representing 10 genotypes of Ch. angustifolium were regenerated under in vitro conditions, hardened and planted in the field. Studies included an evaluation of shoot proliferation, phytochemical assessment of in vitro and ex vitro plants as well as investigations of intraspecies variability regarding four phenological stages: vegetative, beginning of blooming, full blooming, and green fruit phases. Quantitative and qualitative analyses of bioactive compounds were performed using high-performance liquid chromatography coupled with diode array detector and tandem mass spectrometer (HPLC–DAD–MS/MS) and high-performance liquid chromatography (HPLC) methods. The efficiency of shoot multiplication varied between genotypes from 8.12 to 21.48 shoots per explant. A high reproduction rate (> 20 shoots per explant) was recorded for four lines (PL_45, PL_44, PL_58, DE_2). Plants grown in vitro synthesized oenothein B (11.2–22.3 mg g−1 DW) and caffeic acid derivatives. Plants harvested from field contained the full spectrum of polyphenols characteristic for this species, and oenothein B and quercetin 3-O-glucuronide were the most abundant. The maximal content of oenothein B was determined in the vegetative phase of fireweed, while some flavonoids were found in the highest amount in full blooming phase. The results of analysis of variance indicated significant differences among genotypes in oenothein B, 3-O-caffeoylquinic acid and flavonoids accumulation in four phenological phases. PL_44 plants were characterized by high content of oenothein B and quercetin 3-O-glucuronide as well as a relatively high level of other flavonoids. Based on our phytochemical and micropropagation studies, PL_44 genotype was the best candidate for early selection and further breeding programs.


2008 ◽  
Vol 54 (6) ◽  
pp. 501-508 ◽  
Author(s):  
Karina Cogo ◽  
Michelle Franz Montan ◽  
Cristiane de Cássia Bergamaschi ◽  
Eduardo D. Andrade ◽  
Pedro Luiz Rosalen ◽  
...  

The aim of this in vitro study was to evaluate the effects of nicotine, cotinine, and caffeine on the viability of some oral bacterial species. It also evaluated the ability of these bacteria to metabolize those substances. Single-species biofilms of Streptococcus gordonii , Porphyromonas gingivalis , or Fusobacterium nucleatum and dual-species biofilms of S. gordonii – F. nucleatum and F. nucleatum – P. gingivalis were grown on hydroxyapatite discs. Seven species were studied as planktonic cells, including Streptococcus oralis , Streptococcus mitis , Propionibacterium acnes , Actinomyces naeslundii , and the species mentioned above. The viability of planktonic cells and biofilms was analyzed by susceptibility tests and time-kill assays, respectively, against different concentrations of nicotine, cotinine, and caffeine. High-performance liquid chromatography was performed to quantify nicotine, cotinine, and caffeine concentrations in the culture media after the assays. Susceptibility tests and viability assays showed that nicotine, cotinine, and caffeine cannot reduce or stimulate bacterial growth. High-performance liquid chromatography results showed that nicotine, cotinine, and caffeine concentrations were not altered after bacteria exposure. These findings indicate that nicotine, cotinine, and caffeine, in the concentrations used, cannot affect significantly the growth of these oral bacterial strains. Moreover, these species do not seem to metabolize these substances.


2008 ◽  
Vol 74 (6) ◽  
pp. 524-529
Author(s):  
Peter E. Fischer ◽  
Timothy C. Fabian ◽  
Waldemar G. Derijk ◽  
Norma M. Edwards ◽  
Michael Decuypere ◽  
...  

Vascular reconstruction using prosthetic materials in contaminated fields can lead to infection, graft loss, and subsequent amputation. We hypothesized that minocycline and rifampin bound to an ePTFE graft using a unique methacrylate technology would provide for resistance from infection and controlled antibiotic elution. Kirby Bauer susceptibility testing was performed on plates overlaid with Staph aureus (SA) and Staph epidermidis (SE) using 6 mm diameter discs of uncoated graft or antibiotic coated graft (ABX). Zones of inhibition (ZIH) were determined after 24 hours. ABX grafts were then placed in a continuous water bath and a recirculating, pulsatile flow device. Susceptibility testing and high performance liquid chromatography with mass spectroscopy was performed to determine graft performance and antibiotic elution rate. ABX grafts had an average ZIH of 35 mm for SA and 44 mm for SE (each P < 0.0001). After the 1 week water bath, the ZIH of the ABX grafts was 23 mm on both the SA and SE plates. The high performance liquid chromatography with mass spectroscopy revealed that after 24 hours, 50 per cent of the antibiotics remained on the graft, and there was a sustained elution for 7 days. Minocycline and rifampin can be bound to ePTFE vascular grafts using a unique methacrylate method. In vitro, the grafts provide a slow elution of antibiotics that provide resistance from infection by SA and SE for up to 2 weeks after graft insertion.


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