Plasma tissue factor and tissue factor pathway inhibitor levels in patients with disseminated intravascular coagulation

We measured the plasma levels of tissue factor (TF) and tissue factor pathway inhibitor (TFPI) in patients with disseminated intravascular coagulation (DIC) to examine the relationship between TFPI and vascular endothelial cell injury. Plasma TF (273 ± 90 pg/ml) and TFPI (252 ± 125 ng/ml) levels were significantly increased in patients with DIC compared with non-DIC patients. Plasma TF antigen level was significantly increased in pre-DIC patients (285 ± 85 pg/ml), while the plasma TFPI level (152 ± 54 ng/ml) was not markedly increased in such a state. The plasma TF/TFPI ratio was high in the pre-DIC patients (2.10 ± 0.90), and low in the DIC patients (1.40 ± 0.87) and healthy volunteers (0.84 ± 0.26). There was no significant difference between the DIC patients with a good outcome and those with a poor outcome in terms of plasma TF levels, although the plasma TFPI level in the DIC patients with a good outcome (289 ± 133 ng/ml) was significantly higher than those with a poor outcome (187 ± 75 ng/ml). During the clinical course of DIC, plasma TF antigen was increased first, and an increase of the plasma TFPI level followed the increase in plasma TF level. These findings suggest that plasma TFPI is released from vascular endothelial cells and it may reflect vascular endothelial cell injury. It is conceivable that TF and TFPI may play an important role in the onset of DIC. Am. J. Hematol. 55:169–174, 1997. © 1997 Wiley-Liss, Inc.     

Tissue factor in plasma of patients with disseminated intravascular coagulation

Recently it has been shown that tissue factor (TF), an important trigger for initiating blood coagulation, is present in the circulating plasma. In order to assess the clinical implications of TF in plasma, plasma concentration of TF was quantitated in 65 patients with disseminated intravascular coagulation (DIC). The mean concentration of plasma TF was elevated in patients with DIC at presentation as compared with healthy subjects (446 ± SD 536 pg/ml vs. 138 ± 51 pg/ml, P < 0.001). Abnormally high levels were found only in 46.2% of the patients, predominantly in patients with non-hematological solid tumors and acute leukemia. Plasma TF did not correlate with hemostatic markers of DIC such as thrombinantithrombin III complex, prothrombin fragment 1 + 2, plasmin-α₂-plasmin inhibitor complex, FDP, D-dimer, or fibrinogen. Serial determinations of plasma TF demonstrated that plasma TF changes roughly in parallel with the course of DIC in most patients with elevated TF at presentation of DIC. These findings suggest that plasma TF is potentially valuable for monitoring the progress of DIC in a limited population of patients. © 1994 Wiley-Liss, Inc.     

Relationship Between Serum Levels of Anti-Low-Density Lipoprotein-Acetaldehyde-Adduct Antibody and Aldehyde Dehydrogenase 2 Heterozygotes in Patients With Alcoholic Liver Injury

We prepared low-density lipoprotein (LDL)-acetaldehyde-adduct (hereafter abbreviated as LDL-adduct) and anti-LDL-adduct antibody by using Watanabe hyperlipidemic rabbits, and determined values of serum anti-LDL-adduct antibody levels by the ELISA method in healthy adults and patients with alcoholic liver injury. In the nondrinking group in healthy adults, values of anti-LDL-adduct antibody levels were 25 ± 13 μ g/ml, and there was no significant difference between moderate drinkers without diseases and the nondrinking group in healthy adults. Values of anti-LDL-adduct antibody in alcoholic disease groups, 17 ± 9 μ g/ml for the patients with the fatty liver group, 21 ± 14 μ g/ml for the hepatic fibrosis group, 70 ± 21 μ g/ml for the alcoholic hepatitis group, 41 ± 50 μ g/ml for the alcoholic cirrhosis group, and 19 ± 18 μ g/ml for the alcoholic pancreatitis group. Examinations of aldehyde dehydrogenase 2 (ALDH2) genetic variations by the polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) method in the healthy group and the liver injury group revealed a tendency for patients with ALDH2¹/2² in the liver injury group to have relatively mild liver lesions. When comparing anti-LDL-adduct antibody levels between ALDH2 genetic variations, those for the patients with ALDH2¹/2¹ (36 ± 40 μ g/ml) were significantly higher than those for patients with ALDH¹/2² (11 ± 5 μ g/ml). Results of the present study suggest that genetic variation may influence the progression of liver injury.     

Effect of granulocyte and monocyte adsorption apheresis on urinary albumin excretion and plasma endothelin-1 concentration in patients with active ulcerative colitis

BACKGROUND/AIM: Increases in microalbuminuria and endothelin (ET-1) are involved in the development of ulcerative colitis (UC) and in its progress. Because granulocyte and monocyte adsorption apheresis has proven to be useful in the treatment of UC, we examined whether urinary albumin excretion and plasma ET-1 concentrations are altered and whether granulocyte and monocyte adsorption apheresis affects the concentrations of these two factors in patients with active UC. METHODS: Twenty patients with active UC and 20 age-matched healthy volunteers (our hospital staffs) were included in this study. UC patients were randomly divided into two treatment groups: a granulocyte and monocyte adsorption treatment group (n = 10) and a conventional treatment group (n = 10). The urine albumin/creatinine ratio, plasma ET-1 concentration and tumor necrosis factor (TNF)-alpha were determined before and after treatment and compared between 2 treatment groups. The 10 adsorption treatment patients underwent 5 consecutive weekly apheresis sessions, each of 60 min duration at a flow rate of 30 ml/min. RESULTS: The urine albumin/creatinine ratio in UC patients (6.4 +/- 2.2 mg/mmol) were higher than that in healthy subjects (1.0 +/- 0.7 mg/mmol, p < 0.01). In addition, the plasma ET-1 level in UC patients (3.5 +/-1.5 pg/ml) was higher than that in healthy subjects (0.8 +/- 0.4 pg/ml, p < 0.01). Plasma TNF-alpha was detected in UC patients (18.8 +/- 8.4 pg/ml), but not in healthy subjects. The urine albumin/creatinine ratio was highly correlated with the plasma ET-1 level (r = 0.62; p < 0.01) and plasma TNF-a level (r = 0.66, p < 0.01). Granulocyte and monocyte adsorption apheresis reduced the urine albumin/ creatinine ratio from 6.6 +/- 2.4 to 1.8 +/- 0.6 mg/mmol (p < 0.01), reduced the plasma ET-1 level from 3.7 +/- 1.6 to 1.4 +/- 0.6 pg/ml (p < 0.05) and reduced the plasma TNF-alpha from 19.2 +/- 8.6 to 3.8 +/- 1.2 pg/ml (p < 0.01). Conventional treatment did not affect these factors. CONCLUSION: Our data suggest that increases in the urine albumin/creatinine ratio, ET-1 and TNF-alpha play an important role in active UC and that granulocyte and monocyte adsorption apheresis is effective in ameliorating such increases.     

Comparison of Three Methods for Measuring Vitamin B12 in Serum: Radioisotopic, Euglena gracilis and Lactobacillus leichmannii

Summary. The vitamin B₁₂ content of 481 sera was estimated by a radioisotopic assay and 478 of the sera were also assayed by the Euglena gracilis method and 396 by the Lactobacillus leichmannii method. The serum vitamin B₁₂ level in normal subjects ranged from 235 to 1470 pg/ml, mean 497 pg/ml (radioisotopic), 170–1144 pg/ml, mean. 460 pg/ml ( E. gracilis ) and 155–1075 pg/ml, mean 471 pg/ml ( L. leichmannii ). In general, the radioisotopic assay gave higher results than the other two methods and the E. gracilis assay gave the lowest results. The E. gracilis assay gave the clearest distinction between normal subjects and patients with untreated pernicious anaemia. A large number of post-gastrectomy and folate deficient patients and occasional patients with other conditions gave subnormal results by one or both of the microbiological assays but normal values by the radioisotopic assay.
The serum vitamin B₁₂ level measured by both the E. gracilis and radioisotopic assays rose with folic acid therapy in two folate deficient patients. In one of them, the values by the two assays were initially 100 pg/ml apart and remained this degree apart during the response, while in the other patient the two assays gave almost identical results both before and during the response to folic acid therapy.     

Beta2-glycoprotein I in thrombosis: evidence for a role as a natural anticoagulant

Although the physiological role of beta₂-glycoprotein I (B₂GPI) is unknown, in vitro evidence indicates that B₂GPI may be a natural anticoagulant. In this study we have examined whether fluctuations of plasma B₂GPI occur in in vivo coagulation. Serial measurements of B₂GPI and other anticoagulant proteins were performed in 51 patients with thrombotic (group 1: six patients with disseminated intravascular coagulation (DIC), group 2: venous ( n =4) or arterial ( n =17) thrombosis) and non-thrombotic disease (group 3: 24 patients undergoing elective surgery). Reductions in plasma B₂GPI levels were seen in most patients which were roughly proportional to the severity of their illness. Particularly striking reductions of B₂GPI, protein C (PC) and antithrombin III (AT-III) (mean ± 95% CI: 42.7 ± 8.6%, 42.1 ± 14.8%, 39.1 ± 28.4% respectively) were seen in group 1. The reductions in plasma B₂GPI were significantly greater in group 1 than in the other groups. Dilutional factors explain most of the reductions in B₂GPI, PC and AT-III in groups 2 and 3, but contribute little to group 1. In conclusion, although B₂GPI behaves as a 'negative acute phase reactant', the magnitude of reduction of plasma B₂GPI levels, accompanied by reductions in other anticoagulant proteins in patients with DIC, suggests specific consumption of B₂GPI in in vivo coagulation. This study provides further evidence that B₂GPI is an anticoagulant of physiological importance.     

Induction of tissue factor expression in human monocyte/endothelium cocultures

Summary. Induction of tissue factor (TF) expression on monocyctes and endothelial cells is central to the development of septic coagulopathy. Serum concentrations of endotoxin in septic patients who develop disseminated intravascular coagulation (DIC) do not, however, reach the levels that would directly stimulate TF expression on either monocytes or endothelium. We show, using an in vitro coculture system, that the interaction of monocytes with endothelium induces the expression of significant levels of TF. Unstimulated cocultures of monocytes (2 × 10⁴/well) and endothelial cells (2 × 10⁴/well) produced 35.3± 8.5 mU of PCA/well, representing a 5-fold increase over the combined PCA of each cell type cultured alone (7.1 ± 1.5 mU, n = 6, P < 0.001). Significant enhancement was also found in the presence of low concentrations of LPS. Induction of TF protein was confirmed by Western blotting. Fixation of monocytes with paraformaldehyde completely abolished TF induction in cocultures, whereas fixation of endothelium had no effect, suggesting that TF induction occurred in monocytes rather than endothelial cells. Induction of TF in cocultures could be further augmented by preincubating the endothelial cells with IFN-γ. When endothelium was prestimulated with 500U/ml IFN-γ there was 142 ±11% increase over unstimulated cocultures (n = 5, P< 0.01). TF induction was inhibited by 32 ± 6% in the presence of anti-ICAM-1 mAb (n = 5, P < 001). Our results suggest that monocyte interactions with vascular endothelium, regulated by inflammatory cytokines, and mediated by adhesive ligand binding, leads to the induction of functional monocyte TF protein, which may be responsible for the initiation of DIC in sepsis.     

Endogenous Gastrin Release and Antral Gastrin Concentration in Gastroesophageal Reflux Patients and Normal Subjects

In this study we compared both endogenous gastrin release to a known gastrin stimulant, phenylalanine, and fasting antral mucosal gastrin concentration in normal subjects and patients with documented gastroesophageal reflux. Resting lower esophageal sphincter pressure in the reflux patients (14.7 ± 1.5 mm Hg) was significantly less ( p < 0.01) than in the normal subjects (27.5 ± 2.7 mm Hg). Basal serum gastrin concentrations were similar in the two groups. There were significant ( p < 0.05) increases in peak serum gastrin in response to intragastric administration of phenylalanine in both normal subjects (20.6 ± 6.7 pg/ml, p < 0.05) and refluxers (22.4 ± 3.0 pg/ml, p < 0.01) but there were no significant differences in these responses between normals and refluxers. Mean integrated gastrin response to phenylalanine in the reflux patients (812 ± 116 PG ml⁻¹ h⁻¹) was slightly higher than that in normals (609 ± 328 pg ml⁻¹ h⁻¹) although the difference was not significant. Antral gastrin concentration was slightly higher in reflux patients (15.7 ± 2.2 ng/mg tissue) than in normals (10.4 ± 4.2 ng/mg tissue), although this difference was not significant. There was no correlation between antral gastrin concentration and either integrated serum gastrin response or gastric acid output. We conclude that there is no difference between patients with gastroesophageal reflux and normal subjects with regard to serum gastrin levels, endogenous gastrin release, or antral gastrin concentration. These observations suggest no role for gastrin in the mediation of lower esophageal sphincter incompetence or the pathophysiology of gastroesophageal reflux.     

Plasma glutathione concentration in patients with chronic hepatitis C virus infection

Summary. It has recently been proposed that a depletion of glutathione (GSH) may be a contributing factor to viral persistence and resistance to interferon-α (IFN-α) therapy in chronic hepatitis C virus (HCV) infection. The aim of this study was: (1) to compare plasma GSH levels in patients with chronic HCV infection and normal healthy controls; and (2) to correlate GSH levels with liver histology and serum HCV RNA levels. Twenty-four patients with compensated chronic hepatitis C and 2 7 healthy subjects were studied. Serum and heparinized plasma were prospectively prepared and frozen within 1 h of collection. Plasma glutathione and glutathione peroxidase (GP) levels were measured spectrophotometrically. The serum HCV RNA level was quantitated by the branched chain DNA signal-amplification assay. Plasma GSH levels were not decreased in patients with chronic HCV infection but were actually greater than in controls (control 1.2 7 ± 0.12 μg ml^-1, HCV 1.62 ± 0.11 μg ml^-1, P < 0.05). There was also no difference in plasma GP activity between these two groups (control 0.233 ± 0.007 U ml^-1, HCV 0.230 ± 0.007 U ml^-1). Among the patients with chronic HCV infection, there was no correlation between either plasma GSH or GP levels and the serum alanine aminotransferase (ALT) or aspartate aminotransferase (AST), serum HCV RNA level, or liver histology. This study demonstrates that chronic HCV infection does not decrease the plasma GSH and GP levels.     

Vitamin B12 Levels in Erythrocytes in Anaemia due to Folate Deficiency

In folate-deficiency anaemia erythrocyte vitamin B₁₂ levels were low before treatment began (mean = 80 ± 13.1 pg/ml). A rapid rise occurred during folic acid therapy (mean peak = 375 ± 207 pg/ml) and was followed by a slow fall towards normal (mean = 170 ± 54 pg/ml).     

Development and clinical application of a new ELISA assay to determine plasmin–α2-antiplasmin complexes in plasma

Plasmin–α₂-antiplasmin complexes (PAP) are considered good markers of fibrinolytic activation in vivo . The presence of neoantigens in these complexes offers the possibility to develop specific immunoassays to determine PAP levels. We have developed a sensitive PAP purification method in vitro by adding urokinase to fresh plasma followed by affinity chromatography to lysine-sepharose and elution with ε-aminocaproic acid. This material, characterized by SDS-PAGE and Western blotting, was used to raise monoclonal antibodies (MoAbs). We describe a new enzyme-linked immunosorbent assay (ELISA) to quantify PAP complexes in plasma. The assay follows the sandwich principle and is based on two MoAbs, CPL12 and CPL15, that bind to the modified α₂-antiplasmin moiety and the plasmin moiety of the complex respectively. The calibration curve was constructed with definite concentrations of purified PAP. The lower limit of the assay is 75 ng/ml and the variation coefficients are 3.5% (intra-assay) and 10.6% (interassay). A mean value of 573.5 ± 131.4 ng/ml was obtained from PAP concentration in a healthy population ( n  = 30). Significantly higher PAP levels were observed under diverse clinical conditions in which fibrinolysis is activated: clinical sepsis, acute myocardial infarction (AMI), malignancy, diabetes, pregnancy, elderly people and thrombolytic therapy. From our results we conclude that this ELISA is suitable to measure in vivo plasma PAP levels.     

Elevated plasma tissue factor antigen level in patients with disseminated intravascular coagulation

The plasma tissue factor (TF) antigen level was measured in patients with disseminated intravascular coagulation (DIC). The plasma TF antigen was detected In normal volunteers, and it was significantly higher in DIC patients than in non-DiC patients. However, in some patients with DiC, the plasma TF antigen level was within the normal range. The plasma TF antigen level in patients with DIC significantly decreased after therapy, but it was not correlated with organ failure or outcome. The plasma TF antigen level in patients with DIC was not correlated with other hemostatic markers. The plasma TF antigen level tended to be higher in DIC patients with nonlymphoid leukemia than in those with lymphoid tumor. TF might be implicated in the occurrence and progression of DIC. © 1994 Wiley-Liss, Inc.     

Abnormal factor VIII Hiroshima: defect in crucial proteolytic cleavage by thrombin at Arg1689 detected by a novel ELISA

We have established an ELISA for detecting thrombin cleavage of the FVIII light chain at Arg¹⁶⁸⁹. The method used a coating alloantibody which recognized amino acid residues 2248–2312 in the C2 domain, together with a second monoclonal antibody, NMC-VIII/10, which recognized residues 1675–1684 in the amino-terminal region of the light chain. FVIII antigen (FVIII:Ag) was measured after treatment of plasma with various concentrations of thrombin. The FVIII:Ag of normal plasma was reduced in a dose-dependent manner by the thrombin, falling to 28% in the presence of 100 U/ml enzyme. The concentration of thrombin that achieved 50% reduction (IC₅₀) was approximately 1·0 U/ml. The plasma of four haemophilia A positive (A⁺) and two haemophilia A reduced (A^R) patients were analysed. The IC₅₀ of all patients was more than 1·0 U/ml, indicating that thrombin cleavage of the FVIII light chain was defective. One haemophilia A⁺ plasma did not respond to thrombin in this ELISA system. The patient (TI) was a haemophiliac with FVIII coagulant activity of 0·04 U/ml and FVIII:Ag of 1·78 U/ml. In addition, immunoblotting of the purified FVIII from TI showed that thrombin cleavage of the 80 kilodalton (kD) light chain was impaired. The patient's DNA was amplified using the polymerase chain reaction with a set of synthetic oligonucleotide primers spanning amino acid residues 1646–1714. Sequence analysis of the amplified DNA fragments revealed a cytosine to thymine transition, converting an arginine 1689 to cysteine. This abnormal FVIII was designated as FVIII Hiroshima. Our ELISA system is a simple and useful method of evaluating the proteolytic cleavage by thrombin at Arg¹⁶⁸⁹.     

Plasma Cholecystokinin Responses after Ingestion of Liquid Meal and Intraduodenal Infusion of Fat, Amino Acids, or Hydrochloric Acid in Man: Analysis with Region Specific Radioimmunoassay

A highly sensitive and precise radioimmunoassay system for plasma cholecystokinin (CCK) was developed with the anli-CCK-8 specific antiserum which raised against N-terminal amino acids residue of sulfated CCK-8 and reacted with CCK-8, CCK-33, and CK-39 but not with gastrin and its related peptides. Mean concentration of the fasting plasma CCK determined with this method using CCK-8 as standard was 12.9 ± 5.9 pg/ml in normal subjects (n = 26), and in patients with hepatic cirrhosis it was significantly higher (36.7 ± 16.9 pg/ml, n = 9, p < 0.01) than in normal subjects. In six young healthy volunteers, intraduodenal infusion of fat caused a significant increase ( p < 0.05) of plasma CCK from a basal level of 8.0 pg/ml to a peak of 43.0 ± 12.0 pg/ml at 20 min after starting of infusion. In the same subjects, a significant increase of plasma CCK was also observed by amino acids infusion, but no elevation of plasma CCK level was found during intraduodenal acidification.     

Tissue factor antigen and activity in serum of postoperatively shed blood used for autologous transfusion.

Orthopaedic surgery involves extensive dissection of connective and richly vascularised tissues rich in tissue factor (TF). It was, therefore, of interest to quantify the amount of TF antigen and activity in postoperatively drained, unwashed wound blood collected for the purpose of autologous transfusion. In nine young patients subjected to surgery for idiopathic thoracic scoliosis, samples were drawn postoperatively from collected shed blood, a pulmonary artery catheter and a radial arterial cannula prior to, during and after reinfusion of shed blood (10 ml/kg body weight), and analysed for TF antigen and activity. Preoperative arterial control samples contained 128 pg/ml TF antigen compared with 40 pg/ml postoperatively. During reinfusion of drained blood, arterial TF concentration rose to 96 pg/ml and dropped to 64 pg/ml after infusion. Arterial and mixed venous blood did not differ significantly in TF levels. Serum from drained blood contained high concentrations of TF antigen (773 pg/ml), but no TF activity was detected. It is concluded that the high concentrations of TF antigen in serum from postoperatively drained blood collected for autologous transfusion are devoid of procoagulant activity. The TF antigen in plasma of drained blood is suggested to be a soluble, proteolysed TF-apoprotein or a TF complex inactivated by the TF pathway inhibitor (TFPI).     

组织因子和组织因子途径抑制物1对无复流作用的实验研究

目的 观察缺血再灌注时兔心肌组织和血浆中组织因子(TF)和组织因子途径抑制物1(TFPI-1)水平的变化,研究外源性TFPI-1对无复流严重程度的影响,探讨TF激活的外源性凝血系统及TFPI-1抑制途径在无复流发病过程中的作用.方法 40只新西兰大白兔随机分为4组(每组10只):缺血再灌注组(IR组,结扎回旋支120 min,再灌注60 min)、缺血再灌注TFPI-1组(TFPI-1组,再灌注时rTFPI-1 100 ng/kg静脉注射,1ng·kg~(-1)·min~(-1)静脉滴注)、缺血组(结扎回旋支180 min)和假手术组,每组10只.用硫磺素S和Evan's蓝活体染色区分无复流区和缺血区.无复流严重程度用无复流面积/缺血面积表示.用逆转录-聚合酶链反应方法测定无复流区、缺血区及正常区心肌组织TF和TFPI-1 mRNA表达水平,ELISA方法测定开胸前、冠状动脉结扎前即刻及结扎120 min、再灌注10和60 min血浆TF和TFPI-1水平.结果 开胸前、冠状动脉结扎前即刻及结扎120 min,各组血浆TF、TFPI-1水平差异无统计学意义(P>0.05);再灌注10和60 min时,IR组血浆TF水平均显著高于缺血组和假手术组[10min:(20.7±4.1)pg/ml比(13.9±2.2)pg/ml(P<0.001),(20.7±4.1)pg/ml比(13.2±2.6)pg/ml(P<0.001);60 min:(15.8±2.6)pg/ml比(13.5±1.6)pg/ml(P<0.05),(15.8±2.6)pg/ml比(12.1±0.7)Pg/ml(P<0.001)].再灌注10 min时,IR组血浆TFPI-1水平较缺血组及假手术组无明显变化(P>0.05);60 min时,血浆TFPI-1水平[(9.7±1.6)ng/ml]反而显著低于缺血组[(11.6±1.6)ng/ml,P<0.05]及假手术组[(10.1±1.3)ng/ml,P<0.01].IR组无复流区心肌组织TF mRNA表达高于缺血组及假手术组(P<0.05或P<0.001);TFPI-1 mRNA表达较缺血组无明显变化(P>0.05).TFPI-1组无复流严重程度明显低于IR组(0.39±0.11比0.54±0.06,P<0.01).结论 无复流区心肌组织TF转录水平及再灌注过程中TF血浆蛋白水平表达明显上调;而无复流区心肌组织TFPI-1转录水平无明显变化,再灌注过程中血浆蛋白水平反而相对降低;外源性rTFPI-1可以减轻无复流严重程度.TF激活的外源凝血途径在无复流发病过程中起到重要作用.     

Measurement of thrombus precursor protein in septic patients with disseminated intravascular coagulation and liver disease

BACKGROUND AND OBJECTIVES: Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic intravascular activation of coagulation leading to the widespread deposition of fibrin in the circulation. Therefore, the determination of soluble fibrin is crucial for the diagnosis of DIC. Thrombus precursor protein (TpP) levels can be determined as a measure of soluble polymers, which are the immediate precursors of insoluble fibrin. In this study, the potential diagnostic usefulness of this TpP test was investigated in septic patients with DIC and liver diseases. DESIGN AND METHODS: TpP analysis was performed on 155 plasma samples from 95 septic patients, including 72 patients without liver disease and 23 patients with liver diseases, and on 42 plasma samples from normal healthy subjects. The study population was subdivided according to three phases of DIC described as compensated, decompensated and full-blown DIC. Plasma TpP level was determined using a new assay, the TpPTM (American Biogenetic Sciences, USA), which is based on an ELISA method. RESULTS. Septic patients with decompensated (16.1 9.1 mg/mL) or full- blown (20.9 12.4 mg/mL) phases of DIC had significantly higher TpP levels than those with the compensated (5.6 6.2 mg/mL) phase of DIC or healthy controls (2.9 1.6 mg/mL). In septic patients with liver disease, a significant difference was found between the TpP levels of patients with full- blown DIC (21.6 10.6 mg/mL) and those of patients with the decompensated phase (13.4 6.5 mg/mL). Plasma TpP levels correlated significantly with other DIC parameters including platelet count, fibrinogen, antithrombin and TAT, and correlated weakly with D-dimer. INTERPRETATION AND CONCLUSIONS: Our findings indicate that septic patients who developed decompensated or full-blown DIC or organ dysfunction have significantly higher plasma levels of TpP, and suggest the potential usefulness of the TpP assay as an aid to the diagnosis of DIC in cases of sepsis and liver disease complicated by sepsis.     

Evaluation of an enzyme-linked immunosorbent assay for detection and quantification of hepatitis B virus PreS1 envelope antigen in serum samples: comparison with two commercial assays for monitoring hepatitis B virus DNA

An in-house sensitive and easy-to-use solid-phase enzyme-linked immunoassay (ELISA) was adapted for the detection and quantification of hepatitis B virus (HBV) PreS1 envelope antigen in serum, and compared with the HBV DNA Hybrid Capture^™ system from Murex and the polymerase chain reaction (PCR) Amplicor^™ HBV Monitor assay from Roche. Twenty-five patients with chronic hepatitis B after liver transplantation were included in this study. The sensitivity of our ELISA was found to be 50 pg of HBsAg/PreS1Ag ml^–1. The linearity was between 0.1 and 100 ng ml^–1. Intra-assay reproducibility was obtained with a standard deviation of <1%. No correlation between the presence of serum PreS1 antigen and viral DNA detected by direct hybridization (Murex) was observed. In contrast, there was a significant 96% correspondence in the presence of PreS1 antigen and viral DNA detected and quantified by the PCR assay (Roche). In conclusion, the most important and reliable markers for monitoring residual HBV replication in serum were HBV DNA by the PCR assay, and virus envelope PreS1Ag by our in-house ELISA. Thus, PreS1Ag disappearance in serum could be used for evaluating the efficacy of antiviral therapies.     

Plasma Renin Activity and Hypertension in Acute Glomerulonephritis*

Summary: The relationship between plasma renin activity (PRA), plasma volume (PV) and mean arterial pressure (MAP) in children with acute glomerulonephritis was assessed in two groups of patients between the ages of three to six years. One group with normal blood pressure (13 children) and a group with significantly elevated blood pressure (20 children) were compared with a control group of ten normal children.
In patients who developed hypertension (MAP: 113 ± 3 mmHg), the mean PRA was 0±45 ± 0±1 ng/ml/hr, and the mean PV measured in ten of these children was 1526 ± 47±9 ml/M². In the group of normotensive patients with acute glomerulonephritis (MAP = 79 ± 1±8 mmHg), the mean PRA was 1±6 ± 0±32 ng/ml/hr, the mean PV in four of these patients was 1285±37±6 ml/M². The children in the control group (MAP = 77± 1±6 mmHg) had a mean PRA of 7±93 ± 0±2 ng/ml/hr and six of these children had a mean PV of 1115 ± 103 ml/M².
The results showed children who developed hypertension had significantly higher PV lower PRA than children with acute glomerulonephritis who were normotensive and the control subjects. A positive correlation was found between MAP and PV and negative correlation between MAP and PRA. There was no significant difference in MAP, PV and PRA between children with acute glomerulonephritis with normal blood pressure and children in the control group.     

Hemostatic implications of endothelial cell apoptosis in obstructive sleep apnea

Patients with obstructive sleep apnea (OSA) are at increased risk of atherothrombosis independent of the Framingham risk factors. Studies on hemostasis factors in OSA are scarce and inconsistent. We sought to understand the variation in atherothrombotic propensity as a function of apoptotic circulating endothelial cells (CECs) in OSA by investigating the relationship between CEC apoptosis and plasma levels of hemostatic factors tissue factor (TF) and von Willebrand Factor (vWF) in apneic subjects. Apoptotic CECs were detected by flow cytometry in 35 male subjects free of cardiovascular diseases (AHI range 8–43) and 12 healthy male controls (AHI range 2–5) before and after 8 weeks of nasal continuous positive airway pressure (nCPAP). Quantitative determination of TF and vWF was performed using an enzyme-linked immunosorbent assay (ELISA) kit. The mean levels of TF (66.78 ± 41.59 pg/ml) and vWF (189.70 ± 69.24 IU/dl) were significantly higher in OSA patients compared with those in healthy subjects (42.83 ± 14.18 pg/ml; and 124.48 ± 31.43 IU/dl). Apoptotic CECs were elevated in patients with OSA and correlated strongly with TF and vWF levels (p = 0.02 and p < 0.001; respectively). There were no correlations between TF, vWF and apnea hypopnea index, or arousal index. Only the percentage of time spent <90% oxygen saturation was inversely associated with TF (r = 0.38; p = 0.02). Following nCPAP therapy, there was significant decrease in TF levels that correlated with decrease in apoptotic CECs. In patients with OSA, increased prothrombotic factors are strongly determined by apoptotic CECs. Treatment with nCPAP may alleviate the coagulation propensity.