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PubMed2006

Dynamic analysis of coagulation of low turbidity water sources using Al- and Fe-based coagulants.

The direct filtration system is widely used in the treatment of source waters with low and stable turbidity. We have previously indicated the importance of optimizing agitation strength GR and time TR in rapid mixing tanks in order to decrease filter head loss and treated water turbidity in direct filtration. In the present study, we employ a batch-type coagulation experimental apparatus that incorporates a high-sensitivity particle counter, where the particulate concentrations are measured continuously after injection of coagulant, in order to clarify the fundamental coagulation and microfloc formation dynamics. Specifically, it is shown that, after injection of the coagulant, coagulation and microfloc formation occur through distinct periods: an agglomeration preparation period, followed by an agglomeration progression period, and then finally an agglomeration stabilization period, and that optimization of the GR value is the most important consideration, although both the coagulant concentration and GR influence the time at which agglomeration begins in the preparatory period, the time at which agglomeration stabilizes after the progression period, and the concentration of initial particles with diameters of 1-3 microm at completion of agglomeration.

Alum Compounds↗

PubMed1969

Placental barrier to coagulation factors: its relevance to the coagulation defect at birth and to haemorrhage in the newborn.

The placental barrier to coagulation factors was assessed by measuring their levels in maternal venous and neonatal umbilical arterial and venous blood and was found to be largely complete. Detailed coagulation assessments in a large number of term and premature neonates showed that term neonates had a mild coagulation deficiency at birth. Premature neonates had a more definite deficiency, which became more severe with increasing prematurity. Mortality in low birth weight premature infants was associated with a severe coagulation deficiency, and was frequently due to cerebral haemorrhage. It is suggested that the coagulation system of low birth weight infants should be assessed to enable prophylactic treatment of those with a severe deficiency.

Birth Weight↗

PubMed1975

IgE-induced blood coagulation alterations in the rabbit: consumption of coagulation factors XII, XI, and IX in vivo.

Intravenous administration of BSA into 3-month-old rabbits producing detectable anti-BSA antibody only of the IgE class of immunoglobulin induced a variety of intravascular blood coagulation alterations observed in the plasma 15 min after antigen challenge included: a) the intravascular consumption of intrinsic blood coagulation factors XII, XI, and IX and possibly the reduction in clottable fibrinogen; b) a significant prolongation of the activated partial thromboplastin time but not the prothrombin time; and c) the production of an inhibitor affecting the last stage of blood coagulation. The observed blood coagulation alterations were not caused by the manipulative procedures utilized, the presence of anti-BSA, IgG or IgM antibody, histamine-induced alterations in the vascular endothelium or the development of hypotensive shock. It is proposed that specific IgE antibody can induce directly or indirectly the activation of intrinsic blood coagulation in vivo.

Aminocaproates↗

PubMed1998

Contradictory functions of sulfatide in the blood coagulation system as coagulant and anticoagulant.

Sulfatide (galactosylceramide I3 -sulfate) has been reported to activate blood coagulation factor XII (Hageman factor), which suggests that it exhibits coagulant activity (Fujikama et al., 1980 Biochemistry 19, 1322-1330) However, sulfatide administered into animals as a bolus shot without subsequent thrombus formation, prolonged conventional clotting times and bleeding time (Hara et al., 1996 Glycoconjugate J. 13, 187-194). These findings suggest that it may exhibit anticoagulant rather than coagulant activity. Following this suggestion we found in vitro that binding of sulfatide to fibrinogen resulted in disturbance of fibrin formation. To examine a possible pharmacological effect of sulfatide on blood coagulation in vivo we continuously infused sulfatide into rats through plastic cannulae and found formation of giant thrombi around the tips of the cannulae. These data suggest that sulfatide may exhibit contradictory functions in the blood coagulation system.

Animals↗

PubMed1996

Magnesium(II) is a crucial constituent of the blood coagulation cascade. Potentiation of coagulant activities of factor IX by Mg2+ ions.

We recently showed that not only Ca2+ ions but also Mg2+ ions play a crucial role in stabilizing the native conformation of coagulation factor IX. We here report that Mg2+ ions at physiological concentrations greatly augment the biological activities of factor IX. In clotting assays with dialyzed plasma, addition of Mg2+ ions enhanced the apparent coagulant activity of factor IXa, while that of factor Xa was scarcely affected. Activation of factor X by factor IXa in the presence of factor VIIIa, phospholipids, and Ca2+ ions was accelerated by Mg2+ ions. It appeared that the cation increased the affinity between factor IXa and factor VIIIa, thereby increasing the apparent catalytic efficacy of the enzyme. We also evaluated the effect of Mg2+ ions in the coagulation pathway initiated by tissue factor and found that activation of factor IX by factor VIIa*tissue factor was accelerated by the cation. Consequently, clotting of normal plasma induced by factor VIIa*tissue factor was shortened by the cation, while no such effect was observed in plasma deficient in factor IX or VIII. These results indicate that the previously unrecognized plasma component, Mg2+ ions, plays crucial roles in blood coagulation and, moreover, that contributions of factors IX and VIII in the coagulation cascade have been seriously underestimated in previous investigations.

Blood Coagulation↗

PubMed2002

The effect of the combined administration of colloids and lactated Ringer's solution on the coagulation system: an in vitro study using thrombelastograph coagulation analysis (ROTEG.

UNLABELLED: Gelatin solutions are often given in clinical practice once the maximal dose of a median-weight hydroxyethyl starch (HES) has been reached. Colloids are usually combined with lactated Ringer's solution (RL). Whether the combined administration of colloids and/or crystalloids affects blood coagulation is not known. We diluted blood by 20%, 40%, and 60% with RL, gelatin (Gelofusin), 6% HES 130/0.4 (Voluven), and 6% HES 200/0.5 (Iso-Hes), as well as with combinations of these solutions at a ratio of 1:1 (gelatin/RL, 6% HES 130/0.4:RL, 6% HES 200/0.5:RL, 6% HES 130/0.4:gelatin, 6% HES 200/0.5:gelatin). Thereafter, blood was analyzed by using modified thrombelastograph coagulation analysis (ROTEG) and clotting time, clot formation time, and maximal clot firmness were determined. RL had the least effect on hemostasis. Gelatin administered alone impaired the coagulation system significantly less than each median-weight HES administered alone. We conclude that gelatin combined with 6% HES 200/0.5 or 6% HES 130/0.4 decreases hemostasis <6% HES 200/0.5 or 6% HES 130/0.4 administered alone. IMPLICATIONS: The effect of the combined administration of different colloids and/or crystalloids on coagulation is not known. We show that hemostasis is less impaired using a combination of gelatin and median-weight starches than using median-weight starches alone. Furthermore, the combination of lactated Ringer's solution and gelatin decreases the coagulation system to the same extent as the combination of lactated Ringer's solution and 6% hydroxyethyl starch 130/0.4.

Adult↗

PubMed1994

A new blood-coagulating protease in mitochondrial membranes of rat submaxillary glands. Purification and characterization of protease and its blood-coagulating activity.

An integral membrane protease was solubilized and purified to homogeneity from rat submaxillary mitochondria. The purified enzyme could coagulate rabbit plasma. The molecular mass of the enzyme is 22 kDa on SDS-polyacrylamide gel electrophoresis under reducing conditions and 24 kDa on gel filtration on a Sephadex G-100 column. Its isoelectric point is 4.2-4.25. Enzyme activity is strongly inhibited by diisopropyl fluorophosphate, soybean trypsin inhibitor, benzamidine, aprotinin, and antipain, suggesting the enzyme as a serine protease. Its pH optimum for activity is 8.5. Zn2+ is strongly inhibitory; at 1 mM concentration it produced 72% inhibition. The enzyme is active toward different synthetic substrates (p-nitroanilide derivatives) containing Arg at the P1 position with blocked NH2 terminus. Kcat/Km was highest with the substrate N-Bz-Pro-Arg-pNa (where Bz is benzoyl and pNA is paranitroanilide). The purified enzyme coagulates rabbit plasma in a dose-dependent manner. Plasma coagulation by the enzyme is completely blocked in the presence of aprotinin or soybean trypsin inhibitor, suggesting that protease activity is required for this coagulation reaction. Antibody raised against the purified enzyme inhibits the plasma coagulation initiated by the enzyme. The enzyme can correct the prolonged clotting time of factor X-deficient human plasma but is unable to convert purified fibrinogen to fibrin clots, indicating factor Xa-like activity of the enzyme. The enzyme has the ability to activate prothrombin. Several properties of the enzyme distinguish it from other reported submaxillary proteases.

Amino Acid Sequence↗

PubMed1993

[Preoperative monitoring of blood coagulation in urologic operations: diagnosis of familial factor XI deficiency within the scope of preoperative blood coagulation studies].

Presurgical coagulation diagnosis should--apart from coagulation monitoring in the laboratory based on a stepwise diagnosis for detection of coagulations disorders, starting with global tests (NT/APTT) followed by appropriate specific investigation in case of pathological findings--consist of an adequate hemostaseological anamnesis and physical checkup of the patient. This would allow detection of important signs of hemostaseological impairment during the pre-analytical phase already and permit subsequent initiation of more specific coagulation tests. The casuistics of a patient with factor XI-deficiency ("Minor Form"), a condition which is extremely infrequent in our country, demonstrates the coagulation diagnostic procedure which led to detection of his inherited factor XI-deficiency. In addition the pre-, peri- and postsurgical therapeutical management of this particular patient using an antifibrinolytic drug (tranexamic acid) is presented.

Blood Coagulation Tests↗

PubMed1997

Novel and diagnostically applicable information from optical waveform analysis of blood coagulation in disseminated intravascular coagulation.

Transmittance waveform is the term applied to the optical profile generated from the process of clot formation on standard coagulation tests run on the MDA-180, a new-generation automated coagulation analyser. In patients with disseminated intravascular coagulation, a characteristically abnormal 'biphasic change' is seen on both the activated partial thromboplastin time and thrombin time waveforms. Increasing steepness of the initial slope on the waveform correlates with clinical deterioration and fulminant progression. Although the mechanism underlying the biphasic appearance remains to be elucidated, its identification provides the diagnostic laboratory with a simple, rapid and robust assay for disseminated intravascular coagulation that can help the clinician with urgent and appropriate therapeutic interventions.

Blood Coagulation↗

PubMed1996

[The "activated coagulation time (ACT)": two simple screening methods for evaluating coagulation disorders in dogs].

The use of the activated coagulation time (ACT) for testing the intrinsic coagulation is well established among veterinary practitioners in the USA. The advantage of the ACT compared to other coagulation tests is its ease to be performed under practice conditions. The ACT may be measured manually or instrumentally. The reference range of our instrumental measurement is between 90 and 120 seconds (median 105 seconds), of the manual measurement at room temperature between 115 and 145 seconds (median 125 seconds). Advantages of the instrumental method are the smaller amount of blood (0.4 ml versus 2.0 ml) necessary to perform the test, and the smaller potential for errors by unexperienced examiners. The spread is comparable between the two methods. The most important cause of false results is poor venipuncture technique: traumatic venipuncture will trigger the coagulation cascade already during venipuncture causing an artificially shortened ACT.

Animals↗

PubMed2004

Combined epinephrine and bipolar probe coagulation vs. bipolar probe coagulation alone for bleeding peptic ulcer: a randomized, controlled trial.

BACKGROUND: Endoscopic treatment with combined modalities is considered standard of care for patients with high-risk peptic ulcer bleeding. This study compared epinephrine injection plus bipolar probe coagulation with bipolar probe coagulation alone in patients with high-risk peptic ulcer bleeding. METHODS: Patients with endoscopically confirmed peptic ulcer bleeding (active or visible vessel) seen from January 2000 through December 2002 were prospectively randomized to two groups. The study group (n = 58) had epinephrine injection followed by bipolar coagulation; the control group (n = 56) was treated by bipolar coagulation alone. The primary outcomes assessed were the rate of initial hemostasis and the rate of recurrent bleeding. Secondary outcomes were the following: need for surgical intervention to control bleeding, transfusion requirements, length of hospital stay (in days), and 30-day mortality. RESULTS: The rate of initial hemostasis was significantly higher in the combination therapy group ( p = 0.02; absolute risk reduction 31.6%: 95% CI [5.4, 57.7]). There was no significant difference between the two treatment groups with respect to all other outcomes measures, except that significantly fewer units of blood were transfused in the combination therapy group ( p = 0.006). CONCLUSIONS: In patients with active peptic ulcer bleeding, epinephrine injection plus bipolar coagulation achieved significantly higher rate of initial hemostasis. All other outcome measures were similar with either treatment in patients with non-bleeding stigmata.

Acute Disease↗

PubMed2006

Properties and coagulation performance of coagulant poly-aluminum-ferric-silicate-chloride in water and wastewater treatment.

An efficient inorganic polymer coagulant, poly-aluminum-ferric-silicate-chloride (PAFSC), was developed using two approaches: (i) hydroxylation of the mixture of AlCl3, FeCl3 and fresh polysilicic acid in different Al/Fe/Si molar ratios to obtain PAFSCc and (ii) hydroxylated poly-aluminum-iron-chloride (PAFC) combined with aged polysilicic acid in different Al/Fe/Si ratios to produce PAFSCm. The properties of PAFSC in comparison with polyaluminum silicate chloride (PASC) and polyferric silicate chloride (PAFC) were characterized by various experimental methods. The effect of Al/Fe/Si molar ratio on the hydrolysis-polymerization process of Al (III) and Fe (III) in PAFSC solutions was examined by pH titration, and the effect of Al/Fe/Si molar ratio on electrokinetic mobility of PAFSC was studied by Zeta potential measurement. The laboratory experiments were performed to evaluate the PAFSC in comparison with polyaluminum chloride (PAC) for the coagulation of synthetic water samples, actual surface water and wastewater. The results show that interactions exist among aluminum species, ferric species and polysilicic acid, and the Al/Fe/Si molar ratio affects the Zeta potential of the hydrolyzate and the coagulating performance. PAFSC achieved a better water treatment result than PAC. At the same basicity (B) value and Al/Fe/Si ratio, PAFSCc has better coagulation performance than PAFSCm. PAFSC is a new type and high efficiency composite inorganic polymer coagulant.

China↗

PubMed1993

Comparison between the effects of electrosurgical coagulation and hot air coagulation on blood vessels.

Hot air coagulation (HAC) was tested directly on small isolated bleeding vessels, in comparison with two conventional methods of electrosurgical haemostasis, to assess haemostasis and histological damage. Eighty rats, divided into nine experimental and one control group, were used to carry out bipolar (BC) and monopolar coagulation (MC) and HAC at three different output powers, on sectioned and bleeding femoral arteries and veins. Haemorrhages were controlled by the minimum time of coagulation necessary to stop them. Four animals in each group were studied immediately after coagulation, and 4 a week after coagulation. Vascular closures induced by HAC were observed to be as safe as electrosurgical closures, and no complications such as secondary haemorrhage were found. The degree of histological damage and postoperative regeneration induced by HAC was more similar to BC than to MC.

Animals↗

PubMed2004

[Comparison of shaft temperature related treatment efficacy between "air-cooled" microwave coagulation and traditional microwave coagulation].

BACKGROUND & OBJECTIVE: The application and development of traditional percutaneous microwave coagulation therapy (PMCT) has been limited by high shaft temperature. The "air-cooled" PMCT is the newest advancement. This study was to compare shaft temperature related treatment efficacy between "air-cooled" PMCT and traditional PMCT. METHODS: Two pigs underwent traditional PMCT, and "air-cooled" PMCT at 80 W for 10 min separately. Skin injury, surface temperature of guide-needle, charring tissue sticking to the shaft, and lesion shape in 2 pigs were compared. Five patients with liver tumor received traditional PMCT, and 8 patients with liver tumor received "air-cooled" PMCT. Feeling of pain, skin injury, charring tissue sticking to the shaft, local therapeutic efficacy, and recurrence of these 2 groups of patients were compared. RESULTS: In the pig underwent traditional PMCT, surface temperature of guide-needle reached 119-160 Centigrade; skin burn around puncture points was serious; charring tissue stuck to the front of electrodes; a trail sign was observed in coagulated lesion. In the pig underwent "air-cooled" PMCT, surface temperature of guide-needle was 28.8-39.9 Centigrade; no skin injury was found around puncture points; no charring tissue stuck to the front of electrodes; no obvious trail sign was observed in coagulated lesion. In 5 patients received traditional PMCT, 3 had skin injury; 2 had charring tissue stuck to the front of electrode; all felt moderate or serious epigastric pain lasted for 1-8 weeks; 4 had complete coagulation; 1 had local recurrence. In 8 patients received "air-cooled" PMCT, no one had skin injury, and charring tissue stuck to "air-cooled" electrode; 4 felt slight epigastric pain within 1 week; all had complete coagulation; no local recurrence was found. CONCLUSIONS: The technique of "air-cooled" electrode may decrease temperature of shaft safely and reliably, and eliminate side effects arose from high temperature of shaft. Treatment efficacy of "air-cooled" PMCT is better than that of traditional PMCT.

Animals↗

PubMed2002

Hypertonic resuscitation and blood coagulation: in vitro comparison of several hypertonic solutions for their action on platelets and plasma coagulation.

Resuscitation with hypertonic saline (HS) appears to aggravate bleeding in a model of uncontrolled hemorrhage [J. Trauma 28 (1988) 751; J. Trauma 29 (1989) 79; Arch. Surg. 127 (1992) 93]. This property may be related to the anticoagulant effects of HS on plasma clotting factors and platelets [J. Trauma 31 (1991) 8]. The hypothesis in this study is that a hypertonic solution can be developed that would not disturb the blood coagulation mechanism and could be used as an alternative to hypertonic saline.HS and four different 2400 mosM solutions containing monosaccharides and/or glycine were screened for their in vitro effects on plasma clotting times and platelets. Significant prolongations falling outside the normal range were detected in prothrombin time (PT) and thrombin rime (TT) when only 5% of the volume of normal plasma is HS. Platelet function as measured by extent of shape change (ESC) induced by ADP and aggregation induced by thrombin were also critically impaired by HS at a 5% dilution. All alternative solutions-hypertonic glucose, sorbitol, glycine, glucose/glycine, glucose/mannitol/glycine, sorbitol/glycine-caused a significantly reduced impairment in platelet function and the plasma coagulation system. Hypertonic glycine showed a unique ability to fully preserve the function and integrity of the plasma coagulation system. Considering the pre-deposition of the trauma patient to coagulopathy, administration of HS which clearly is a potent anticoagulant and anti-platelet risks further aggravating the coagulopathy. In contrast, hypertonic glycine preserves the blood coagulation mechanism and exhibits the potential for numerous therapeutic applications. Therefore, prompt evaluation of hypertonic glycine as a resuscitative fluid is highly desirable.

Blood Coagulation↗

PubMed1974

[Quick's time and derived times in the study of the extrinsic course of the coagulation process. The PIVKA (protein induced by vitamin K absence or antagonists) in states of chronic disseminated intravascular coagulation].

After reviewing the available methods for the clinical study of the extrinsec way of the coagulative process (Quick's time, Owren's Thrombotest and Normotest), the AA. explain what is the significance that the most of hte researchers ascribe to time-value discrepancies between Thrombotest and Normotest. The AA. remember that while the former is sensitive to the presence of certain inhibitors called PIVKA (Protein Induced by Vitamin K Absence or Antagonists), just as Quick's original time; the latter is on the contrary insensitive to them. Then it provides more significant data about the real rate of factors II, VII, and X. Such inhibitors have been found also in subjects that did not undergo any anti-vitamin K therapy and peculiarly in cases in which a Intravascular Coagulation occurred. Therefore the AA. thought to verify the hypothesis that the detection of a discrepancy between TT and NT could be useful in the clinical diagnosis of I.C. which is a serious and often hardly detectable disorder of haemostasis. The AA. have therefore tested 72 patients, 65 of which showed the evidence of I.C. and 7 with I.C. probabilities. The discrepancy values that were obtained are showed in Table I. The first group (65 cases) was furtherly divided into four subgroups, according to the positivities obtained from SDPS test, as shown in Table II. The AA. can therefore come to the following conclusions: a) In human Intravascular Coagulation, the discrepancy between NT/TT may occur with a frequency of 57 per cent but it is not a constant event. b) The discrepancy rate is generally of low degree, being of high degree only in twelve cases (18.5 per cent. c) Analyzing the discrepancy presence and rate in relation to the number of SDPS test positivities, we can notice that the values are remarkably scattered and it is not possible, only on the basis of these data to make a statistical evaluation of their significativity because the groups are not comparable among them, being in exc3ss the cases in which paracoagulation occurs in a low degree. We can only state that the absence of discrepancy predominates in the cases in which a low number of positivities of SDPS test occurs, and on the contrary the discrepancy is a constant event in the cases in which SDPS test shows a large number of positivities. In consitive test to detect Intravascular Coagulation, but we think the positivity of this test may be a support in doubtful cases.

Blood Coagulation Tests↗

PubMed1993

Disseminated intravascular coagulation: clinical complexities of aberrant coagulation.

When the critically ill patient's clinical course is complicated by disseminated intravascular coagulation (DIC), significant physiologic disequilibrium and life-threatening multisystem events ensue. DIC occurs when an underlying pathologic condition triggers overstimulation of the normal coagulation mechanism resulting in a perplexing clinical picture of disseminated coagulation and excessive fibrinolysis. This article presents a review of normal coagulation physiology and the alterations producing the physiology derangements in DIC. Diagnostic and clinical assessment parameters and therapeutic management goals for the critically ill DIC patient also are included. The critical care nurse's role in knowledgeable assessment, rapid intervention, and ongoing evaluation of the patient's therapeutic responses are essential to maximize positive outcomes for the DIC patient.

Blood Coagulation↗

PubMed1993

[Activation of coagulation and fibrinolysis in patients with abdominal true aortic aneurysm associated with disseminated intravascular coagulation].

Two cases of abdominal true aortic aneurysm (AAA) associated with disseminated intravascular coagulation (DIC) were reported. Case 1 was an 81-year-old male who was admitted because of hematoma on the left leg and in whom was found by MRI an aortic aneurysm of 14 cm in diameter. Coagulation studies indicated DIC by revealing thrombocytopenia, hypofibrinogenemia and increased level of FDP. DIC was well controlled by surgical repair of the aneurysm after the administration of a small dose of heparin. Case 2 was a 60-year-old male who was admitted because of lumbago and hematoemesis and in whom was found by CT and echography an aortic aneurysm of 5.5 cm in diameter. Coagulation studies indicated DIC by revealing thrombocytopenia and an increased level of FDP. On the 2nd hospital day, he suddenly died due to the rupture of the aortic aneurysm. In most of 9 cases with AAA without DIC, plasma levels of thrombin-antithrombin III complex, plasmin-alpha 2 plasmin inhibitor complex and FDP-D dimer were also elevated. These findings indicate that the coagulation and fibrinolysis systems were generally activated in patients with AAA, and that DIC tends to occur in patients with a giant aortic aneurysm or an impending ruptured aneurysm.

Aged↗