Concentrations Of Degradation Products Research Articles

Clinical evaluation of the Serum CrossLaps One Step ELISA, a new assay measuring the serum concentration of bone-derived degradation products of type I collagen C-telopeptides

The Serum CrossLaps One Step ELISA is a sandwich assay using two monoclonal antibodies specific for a beta-aspartate form of the epitope EKAHDGGR derived from the carboxy-terminal telopeptide region of type I collagen alpha1-chain. Our objective was to assess the clinical value of the Serum CrossLaps assay for monitoring antiresorptive therapy in osteoporosis treatment. Samples obtained from postmenopausal women treated with different doses of cyclic or continuous hormone replacement therapy (HRT) with an estrogen analog (tibolone) or with a bisphosphonate (ibandronate) were measured in the Serum CrossLaps One Step ELISA at baseline and at various time points during therapy. The corresponding urine samples were measured in the urine CrossLaps ELISA and corrected for creatinine excretion. The serum CrossLaps measurements and corresponding urinary CrossLaps measurements were highly correlated (r >0.8 for all studies). The serum and urine CrossLaps measurements showed a significant decrease among the women treated with clinically relevant doses of either of the antiresorptive agents. Furthermore, the annual percentage change in bone mineral density (BMD) correlated with the measured changes in CrossLaps concentration. The serum CrossLaps assay showed a specificity of 83-100% and a sensitivity of 59-83% for assessing BMD changes. The corresponding values for the creatinine-corrected urinary measurements were 83-92% specificity and 68-79% sensitivity. We conclude that performance of the convenient Serum CrossLaps One Step ELISA is at least equivalent to that of the urine text for follow up of antiresorptive treatment in osteoporosis. Further studies are needed to optimize its use in this and other clinical applications.

Clotting times and antithrombin III activity in cats with naturally developing diseases: 85 cases (1984-1994)

Objective To determine the prevalence of abnormalities of in vitro prothrombin time (PT) and activated partial thromboplastin time (APTT), or antithrombin III (ATIII) activity or all 3 variables in cats; and the association of abnormalities of these variables with naturally developing diseases or disorders. Design Retrospective study. Animals 85 cats from which blood had been obtained for measurement of a coagulation profile (PT, APTT, and ATIII activity) and concentration of fibrin degradation products. Procedure Medical records from the Texas A&M College of Veterinary Medicine were reviewed to determine clinical diagnosis, results of CBC and coagulation profile, and clinical evidence of abnormal bleeding or thrombotic disease. Results 38 cats had one or more abnormality in the coagulation profile; most had multiple abnormalities. Twenty of these 38 cats had concurrent thrombocytopenia. Thrombocytopenia was identified in 9 of 47 cats in which results of the coagulation profile were normal. Most cats did not have clinical evidence of a coagulation disorder, and testing had been requested as part of a diagnostic work-up or before surgery. Diseases commonly associated with laboratory evidence of a coagulation disorder, either singly or in combination, included hepatic disease, neoplasia, and systemic infections. Clinical Implications On the basis of laboratory evidence, hemostatic disorders develop more commonly in cats than clinical signs would suggest. Coagulation profiles may be warranted in high-risk cats to alert clinicians to potential problems. (J Am Vet Med Assoc 1998;213:1290-1295)

Diagnosis of DIC in very low birth weight infants.

Disseminated intravascular coagulation (DIC) occurs most frequently during the neonatal period. We have already established criteria for the early diagnosis of DIC in newborn infants, based on the analysis of clinical and laboratory findings in neonates with and without DIC. In that study, laboratory findings for subjects without DIC were evaluated based on the results obtained from neonates whose birth weights were more than 1500 g. Accordingly, these criteria are not necessarily applicable to the diagnosis of DIC in very low birth weight infants (VLBWI) since the physiological and pathological states of coagulation and fibrinolysis in VLBWI may differ from those of term newborn infants. Therefore, we measured platelet counts, plasma fibrinogen contents and the fibrin degradation product (D-dimer) concentrations in VLBWI with and without DIC. These findings indicate that the scoring system for platelet counts in our diagnostic criteria of DIC in newborn infants is applicable to the diagnosis of DIC in VLBWI. However, our scoring systems for fibrinogen and D-dimer were not usable for the diagnostic criteria of DIC in VLBWI since fibrinogen and D-dimer concentrations in VLBWI without DIC were lower than those in non-DIC neonates whose birth weights were above 1500 g. We devised criteria for the diagnosis of DIC in VLBWI based on those findings.

Study of haemostatic disorders in experimentally induced leishmaniasis in Beagle dogs

Haemostatic alterations in dogs experimentally infected with Leishmania infantum were studied before and after therapy with meglumine antimonate. Haemostatic function tests including platelet count, collagen-induced platelet aggregation, prothrombin time, activated partial thromboplastin time, thrombin time, plasma fibrinogen determination, and serum fibrinogen/fibrin degradation products concentration were performed. In the course of infection and before treatment, moderate thrombocytopenia (P<0·00001) decreased collagen induced platelet aggregation (P=0·0003), prolonged thrombin time (P=0·0117) and increased fibrinogen/fibrin degradation products were observed. Statistically significant differences of plasma fibrinogen concentration, prothrombin time, and activated partial thromboplastin time were not encountered. Haemostatic parameters returned to normal values after therapy. The results indicate that Leishmania infection may impair haemostasis suggesting induction of disseminated intravascular coagulation (DIC), and that treating dogs in an early stage of infection may potentially avoid the possibility of developing an uncompensated DIC.

Haemostatic changes during surgery for primary brain tumours

OBJECTIVEPrimary brain tumours may be associated with coagulation disorders which can pose intraoperative and postoperative management difficulties. The aim was to evaluate the coagulation profile of patients with brain tumours...

Effects of tromethamine buffer on coagulation variables and ionized calcium concentration in dogs

Abstract Objective To evaluate coagulation variables in 2 groups of dogs after tromethamine administration. Animals 13 Beagles. Procedures Both groups of dogs received a 30-minute IV infusion of 10 ml of 0.3M tromethamine/kg of body weight. In unsedated dogs (group 1, n = 8), prothrombin time, activated partial thromboplastin time, normalized ionized calcium concentration, platelet numbers, and platelet function were measured prior to treatment, at the end of the infusion, and 1 hour after the infusion. In xylazine-sedated dogs (group 2, n = 5), buccal mucosal bleeding time and plasma percentage of von Willebrand factor antigen were measured before and 1 hour after infusion, and fibrin degradation products concentration was measured 1 hour after infusion. Platelet function was assessed by determining platelet aggregation and by measuring ATP release from the aggregating platelets over 6 minutes, using a whole blood aggregometer, with 20, 10, and 5 μM ADP and 5 and 10 μg of collagen/ml as platelet activation agonists. Results There was no significant change in any of the variables measured in either group of dogs, compared with baseline values. Conclusions and Clinical Relevance When administered to healthy dogs, tromethamine does not change the coagulation indices measured. (Am J Vet Res 1997;58:777–780)

Environmental interaction of polymers‐natural metabolites as opposed to the degradation products of synthetic polymers

AbstractNatural polymers degrade by a three‐step catabolism and each step generates well‐known metabolites. Detoxication transforms harmful compounds to less harmful ones by the action of microorganisms. Low concentration of degradation products may biomagnify and reach levels that have deleterious effects on humans, animals and plants. The prediction of the environmental interaction of polymers needs knowledge not only about the toxicity of the degradation products but also of the degree of exposure of the living cells to the degradation products.

Coagulation and Fibrinolysis Factors in Healthy Subjects Consuming High Stearic or Trans Fatty Acid Diets

The effects of stearic acid (C18:0) and trans fatty acids on variables related to coagulation and fibrinolysis were studied in 80 healthy humans average age 29 +/- 9 years. All subjects consumed a baseline diet high in saturated fatty acids, mainly from dairy fat for 5 weeks. After this baseline diet they were allocated either to a diet high (8.7% of energy, En%) in trans fatty acids from partially hydrogenated vegetable oil (40 subjects) or a diet high (9.3 En%) in stearic acid (40 subjects) for 5 weeks. All diets contained 32.2-33.9 En% fat, 14.6-15.8 En% saturated plus trans fatty acids, 12.2-12.5 En% cis-monounsaturated and 2.9-3.5 En% polyunsaturated fatty acids and 216-250 mg/10 MJ cholesterol. The fats were mixed into solid foods and almost all daily food was provided. In comparison with the baseline dairy fat diet no change was observed in the concentrations of plasma fibrin degradation products and D-dimers. Also the factor VII coagulant activity (F VII:C), tissue type plasminogen activity (tPA) and plasminogen activator inhibitor activity (PAI-1) were not affected by the experimental diets. Small increase in plasma fibrinogen concentration during the stearic acid diet was statistically significant (from 3.49 to 3.63 g/l: p = 0.041), but probably without any biological significance. Both diets increased plasma level of lipoprotein Lp(a). It can be concluded that as far as coagulation and fibrinolysis are concerned there is no need to differentiate between stearic acid or trans monoenoic fatty acids.

The solubility of morphine and the stability of concentrated morphine solutions in glass, polypropylene syringes and PVC containers

Morphine solutions are frequently used in palliative settings for the treatment of severe cancer pain. There is, however, no complete information concerning the solubility, isotonisation and shelf-life of these solutions. The solubility limits of morphine hydrochloride (M) were determined as 50 mg/ml in water and 5% dextrose, and 30 mg/ml in 0.9% NaCl at 22°C, figures which decreased to 30 and 20 mg/ml, respectively at 4°C. Isotonisation of the M solutions with NaCl or dextrose did not cause any solubility problems at room temperature. The stability of isotonic M solutions and M solutions in water was investigated over a concentration range of 10–50 mg/ml. All solutions were stored in borosilicate glass, polypropylene syringes and PVC containers at 4, 22 and 40°C in the absence of light. Samples were taken immediately after preparation and after 1, 3, 7 and 14 days, 1, 2 and 3 months of storage. All samples were evaluated visually (colour and precipitation) and pH and osmolality were measured. Determination of morphine, morphine- N-oxide, pseudomorphine and apomorphine was done with a reversed-phase ion-pair HPLC assay. During storage at 4°C of M solutions at a concentration above 20 mg/ml, a white precipitate was formed that was difficult to redissolve. In all samples the pH and the osmolality remained nearly unchanged over the study period, except when stored in PVC containers at 22 and 40°C where there was a gradual increase of the osmolality during storage. In the solutions stored in PVC containers at 22 and 40°C an increase in M concentration of up to 105% of the theoretical concentration was detected after 1 month and 1 week, respectively. In all samples only two degradation products were found: morphine- N-oxide and pseudomorphine. During storage the concentration of both degradation products gradually increased, but remained below 0.4% for morphine- N-oxide and below 2% for pseudomorphine. The type of reservoir and the composition of the solution had only a minor influence on the degradation of M. This study indicates that concentrated M solutions are stable for 3 months under all conditions tested, but should be stored at 22°C to avoid precipitation.

Dynamics of fat/oil degradation during frying based on optical properties

The dynamics of a canola based shortening degradation was studied by measuring the concentrations of major degradation products—polymers, decomposition products, free fatty acids and total polar materials and optical properties. The effects of these degradation products were highly significant (P < 0.0001) on turbidity, lightness and photometric colour index. No significant change was observed in the refractive index of the samples. The turbidity decreased with frying time due to the increase in the fat darkness. Transmittance showed high correlations with all the major degradation products only between 550 and 695 nm wavelengths. The redness increased gradually until 5th day of frying and decreased afterwards due to increase in darkness. Similarly, yellowness and chroma increased until day 3 and decreased steadily after that. Lightness decreased and photometric colour index increased with increase in frying time and correlated well with major degradation products.

Degradation products formed during UV-irradiation of humic waters

Natural humic lake water and aqueous solutions of humic substances were treated with ultraviolet (UV) radiation (λ = 254 nm). The effects on the dissolved organic carbon content (DOC) and the absorbance at 254 nm (Abs 254) and 460 nm (Abs 460) were monitored and the identity and concentrations of gas chromatographable organic degradation products were determined. The DOC content and the (Abs 254) of the humic solutions decreased continuously with increasing UV-dose. Several aromatic and aliphatic degradation products were identified and roughly quantified The concentrations of aromatic hydroxy carboxylic acids and hydroxy aldehydes increased when relatively low UV-doses were used, but declined following further irradiation. The concentrations of aliphatic dibasic acids increased over the full range of UV-doses.

DYNAMICS of FAT/OIL DEGRADATION DURING FRYING BASED ON PHYSICAL PROPERTIES

The dynamics of fat/oil degradation were studied by measuring the concentrations of major degradation products, polymers, decomposition products, free fatty acids and total polar materials. Regression models were fitted to predict the changes in physical properties, specific gravity, viscosity, surface tension, specific heat, dielectric constant and capacitance with fat degradation. Fat degradation affected specific heat, specific gravity and viscosity. the dielectric constant or capacitance predicts fat degradation, independent of the food fried. A parallel plate capacitor of larger capacitance was found to produce better correlation with total polar materials in the high polar region.

Effect of Total Flow Rate on the Concentration of Degradation Products Generated by Reaction Between Sevoflurane and Soda Lime

We have compared concentrations of degradation products in the circle system during sevoflurane anaesthesia at different fresh gas flows. Twenty-four patients underwent sevoflurane anaesthesia with fresh gas flows of 1 litre min−1 (1L group), 3 litre min−1 (3L group), or 6 litre min−1 (6L group) (n = 8 in each group). During anaesthesia, the concentrations of degradation products were measured every hour, and the temperature of soda lime, end-tidal carbon dioxide concentration, inspired and end-tidal sevoflurane concentrations, and carbon dioxide elimination were measured. CF2=C(CF3)—0—CH2F (compound A) was the only degradation product detected. The mean maximum concentration of compound A was 19.7 (SD 4.3) ppm in the 1 L group, 8.1 (2.7) ppm in the 3L group and 2.1 (1.0) ppm in the 6L group (P > 0.05). The maximum temperature of soda lime was 44.6 (1.5) °C in the 1 L group, 37.0 (4.4) °C in the 3L group and 29.1 (5.1) °C in the 6L group (P > 0.05). There were no significant differences in end-tidal sevoflurane concentration or mean carbon dioxide elimination between the groups. Only compound A was detected following anaesthesia, with higher concentrations observed at lower flow rates.

Variation of the Flavour and Extractives of European Oak Wood from Two French Forests

Wood from 20 trees from each of two French forests was heat treated and then stored in a 63% ethanol solution. After 6 months the concentrations of lignin degradation products, oak lactones, ellagic and gallic acids in the solutions were measured. The solutions were also assessed for flavour. Analyses of variance and principal component analyses found significant differences between the two forests in both the chemical composition of the solutions and in flavour assessments. Additional trials confirmed that the duration of heating influenced both chemical and flavour characters, but indicated that the effects may vary, depending upon wood properties and origin of the wood.

Variation of the Flavour and Extractives of European Oak Wood from Two French Forests

Wood from 20 trees from each of two French forests was heat treated and then stored in a 63% ethanol solution. After 6 months the concentrations of lignin degradation products, oak lactones, ellagic and gallic acids in the solutions were measured. The solutions were also assessed for flavour. Analyses of variance and principal component analyses found significant differences between the two forests in both the chemical composition of the solutions and in flavour assessments. Additional trials confirmed that the duration of heating influenced both chemical and flavour characters, but indicated that the effects may vary, depending upon wood properties and origin of the wood.

Conjunctive Administration of Intravenous Heparin Attenuates Cross-linked Fibrin Degradation in Patients Treated with Streptokinase

Increases in thrombin activity occur in patients treated with streptokinase, but conjunctive therapy with intravenous heparin does not appear to improve either the rate of early infarct artery patency or survival in patients with acute myocardial infarction. In a recent study we found that concentrations of fibrinopeptide A, a marker of thrombin-mediated fibrin formation, were lower in the first 3 h in patients treated with intravenous heparin (5000 U bolus followed by a fixed-dose 1000 U/h infusion, n = 14) compared with subcutaneous (12,500 U every 12 h, started 4 h after streptokinse, n = 14) administration, but were increased in both groups of patients, consistent with persistent thrombin activity. To determine whether the differential effects of the intensity of heparinization on thrombin formation were reflected in differences in fibrin degradation, we measured cross-linked fibrin degradation products (XL-FDP) before and 1, 2, 3, 8, 12, and 24 h after streptokinase in the same cohort of patients, with a new ELISA with a D-dimer-specific capture antibody (MAb 3B6) and a fibrin-specific tag antibody (MAb 1D2, Agen, Brisbane, Australia). The incidence of early coronary recanalization assessed by creatine-kinase MM isoforms (increase in activity > or = 0.18%/min), was similar in both groups (79 vs 86%). Concentrations of XL-FDP were similar in patients with and without recanalization, but were lower in patients treated with intravenous compared with subcutaneous heparin at 8 h, but the results did not reach statistical significance (627 +/- 151 ng/ml versus 1007 +/- 157 ng/ ml, p = 0.06), and were significantly lower at 12 h (327 +/- 72 versus 781 +/- 162 ng/ml, p = 0.03 at 12 h) (mean +/- SEM). Concentrations of cross-linked fibrin degradation products were also lower in patients in whom the activated partial thromboplastin time was greater than two times the control, compared with those with inadequate anticoagulation (498 +/- 105 versus 1084 +/- 179 ng/ml; p = 0.02) (mean +/- SEM). Thus, more effective inhibition of thrombin with conjunctive intravenous heparin therapy results in less cross-linked fibrin turnover in the first 12 h after thrombolysis with streptokinase. This probably reflects decreased fibrin formation with therapeutic anticoagulation.

Increased fibrin formation in blood in women above the age of 30 who are both oral contraceptive users and smokers

Middle-aged women who are both users of oral contraceptives (OC) and smoke have an increased risk of evolution of myocardial infarction compared with non-users and non-smokers. We have studied the fibrinolytic system in four groups of women above the age of 30: users and smokers (n=12), users and non-smokers (n=16), non-users and smokers (n=14), non-users and non-smokers (n=16). We find no evidence that the balance between the tissue type plasminogen activator and its main inhibitor, plasminogen activator inhibitor type 1, deviates significantly between the four groups. In contrast, plasma concentrations of both plasmin-antiplasmin complexes ( P <0.02) and fibrin degradation products ( P <0.0004) show a significant variation between groups with a biologic gradient from high to low levels as follows: users and smokers→users and non-smokers→non-users and smokers→non-users and non-smokers. These observations suggest that fibrin formation is most excessive in women above the age of 30 who both use oral contraceptives and smoke. Our findings support that older women who use oral contraceptives and smoke have an increased susceptibility to thrombosis.

The role of fibrin degradation products in neutrophil recruitment to the lung.

Pulmonary epithelial injury leads to increased permeability and plasma exudation. Plasma rapidly forms an insoluble fibrin clot in the distal airspace because of the potent procoagulant activity expressed there. Because these airspaces also express potent fibrinolytic activity, digestion of fibrin results in high local concentrations of fibrin degradation products (FDP), which are biologically important molecules with numerous proinflammatory actions. Inflammatory lung injury is associated with neutrophil accumulation, and other matrix proteins affect inflammatory cell traffic. In this study we examined the potential role of FDP in neutrophil recruitment to the lung. Using a chemotaxis assay, we found that FDP are potent chemotactic proteins when neutrophils are prestimulated with lipopolysaccharide (LPS) or formylmethionylleucylphenylalanine (fMLP). Although FDP are high molecular weight proteins, we found that these potent chemoattractants induce polymorphonuclear leukocyte (PMN) migration across epithelial monolayers. The magnitude of response is dependent upon the monolayers' ability to form and maintain tight junctions. Human neutrophil elastase (HNE), another fibrinolytic enzyme released from neutrophils, digests fibrin into chemotactic peptides which are more potent on a weight basis than plasmin-generated FDP. Furthermore, HNE secondarily digests plasmin FDP, producing molecules which are more potent chemoattractants than native plasmin FDP. These observations suggest a potential mechanism whereby FDP may contribute to the neutrophil accumulation which characterizes many inflammatory lung diseases.

Comparison of coagulation test results for blood samples obtained by means of direct venipuncture and through a jugular vein catheter in clinically normal dogs

Objective— To determine whether coagulation test results for blood samples obtained from heparinized jugular vein catheters in dogs are accurate. Design— Prospective, controlled study. Animals— Fourteen clinically normal dogs. Procedure— Prothrombin time, activated partial thromboplastin time, concentration of fibrin degradation products, and fibrinogen concentration were measured in blood samples obtained by means of direct jugular venipuncture and through an indwelling jugular vein catheter 0, 2, 8, 24, and 48 hours after catheter placement. Blood samples were collected from the catheter by means of a 2-syringe technique, which involved discarding the first volume of blood collected. Results— For all sample times, mean values for samples obtained from the jugular vein catheter were not significantly different from mean values for samples obtained by means of venipuncture. Clinical Implications— Blood samples for coagulation tests may be obtained from jugular vein catheters up to 48 hours after catheter placement in clinically normal dogs.

Intravascular and peritoneal coagulation and fibrinolysis in horses with acute gastrointestinal tract diseases

Summary Components of the coagulation and fibrinolytic cascades, prothrombin and activated partial thromboplastin times, endotoxin activity, and albumin concentration were measured in blood and peritoneal fluid from 20 healthy horses and from 153 horses with acute gastrointestinal tract diseases at admission. Overall, 77% (117/153) of affected horses survived to discharge from the hospital, and 85% (82/97) of horses discharged were reported to be normal 9 to 14 months later. Significant differences in hemostatic factors were more common in peritoneal fluid than in blood. Tissue plasminogen activator, plasminogen, protein C, antithrombin III, and α2-arunliplasmin activities and concentrations of fibrinogen and fibrin degradation products were significantly (P &lt; 0.05) greater in peritoneal fluid from horses with colic, and, with the exception of fibrinogen concentration, were associated with detection of endotoxin. Higher values for these variables, except tissue plasminogen activator activity, were significantly (P &lt; 0.05) associated with survival. Plasminogen, antithrombin III, and α2-antiplasmin activities were significantly (P &lt; 0.05) greater in peritoneal fluid from horses with inflammatory or strangulating lesions, compared with those in horses with simple colic. Plasminogen-activator inhibitor type 1 activity, fibrin degradation products concentration, and prothrombin time were significantly (P &lt; 0.05) greater in the blood of horses with colic. Survival was inversely associated with significantly (P &lt; 0.0.5) greater intravascular concentrations of fibrin degradation products and fibrinogen and prothrombin time. This study revealed marked contrasts between peritoneal and intravascular coagulation and fibrinolysis in horses with colic, indicating that inferences regarding the peritoneal environment, particularly with respect to fibrinolytic capacity, should not be made on the basis of factors measured in blood.