Tranexamic acid integrated into platelet-rich fibrin produces a robust and resilient antihemorrhagic biological agent: a human cohort study.

OBJECTIVE: To investigate the incorporation of the antifibrinolytic agent tranexamic acid (TA) during platelet-rich fibrin (PRF) formation to produce a robust fibrin agent with procoagulation properties. STUDY DESIGN: Blood from healthy volunteers was collected. Into 3 tubes, TA was immediately added in 1-mL, 0.4-mL, and 0.2-mL volumes, and the fourth tube was without additions. After PRF preparation, the clots were weighed in their raw (clot) and membrane forms. PRF physical properties were analyzed using a universal testing system (Instron). Protein and TA levels in the PRF were analyzed using a bicinchoninic acid assay and a ferric chloride assay, respectively. RESULTS: The addition of TA to PRF led to a robust weight compared with sham control. PRF weight was greater in females in all tested groups. The addition of TA also led to greater resilience to tears, especially at 1-mL TA addition to the blood. Furthermore, TA addition led to a greater value of total protein within the PRF and entrapment of TA in the PRF. CONCLUSIONS: Addition of TA to a PRF preparation leads to robust PRF with greater protein levels and the amalgamation of TA into the PRF. Such an agent may enhance the beneficial properties of PRF and attribute procoagulation properties to it.

Fibrinolysis Inhibitors: Potential Drugs for the Treatment and Prevention of Bleeding.

Hyperfibrinolytic situations can lead to life-threatening bleeding, especially during cardiac surgery. The approved antifibrinolytic agents such as tranexamic acid, ε-aminocaproic acid, 4-aminomethylbenzoic acid, and aprotinin were developed in the 1960s without the structural insight of their respective targets. Crystal structures of the main antifibrinolytic targets, the lysine binding sites on plasminogen's kringle domains, and plasmin's serine protease domain greatly contributed to the structure-based drug design of novel inhibitor classes. Two series of ligands targeting the lysine binding sites have been recently described, which are more potent than the most-widely used antifibrinolytic agent, tranexamic acid. Furthermore, four types of promising active site inhibitors of plasmin have been developed: tranexamic acid conjugates targeting the S1 pocket and primed sites, substrate-analogue linear homopiperidylalanine-containing 4-amidinobenzylamide derivatives, macrocyclic inhibitors addressing nonprimed binding regions, and bicyclic 14-mer SFTI-1 analogues blocking both, primed and nonprimed binding sites of plasmin. Furthermore, several allosteric plasmin inhibitors based on heparin mimetics have been developed.

[Advances in differential diagnosis and treatment of patients with sarcoidosis]. / Postepy w róznicowaniu i leczeniu chorych na sarkoidoze.

The implementation of treatment in patients with sarcoidosis (SA) must be associated with the certainty of diagnosis, which is difficult due to the lack of unambiguous criteria. Finding the presence of noncaseating granulomas in bioptic material is not always indicative of SA. The main point of SA's diagnosis is the level of its activity, because only patients in the active stage should be qualified for treatment. In therapy, glucocorticosteroids or second-line drugs - methotrexate or azathioprine are still recommended. Introduced monoclonal antibodies (infliximab, etanercept, adaluimumab, golimumab, rituximab), tested for efficacy in other pathologies associated with the formation of granulomas, have a limited application in patients with SA. In contrast, anti-fibrotics (pirfenidone and nintedanib) are in clinical trials. The latest method of controlling the fibrosis of the parenchyma in the course of SA is the use of mesenchymal cells obtained from umbilical cord blood. Preliminary results indicate a real possibility of using this therapy in patients with SA.

Anti-fibrinolytic and anti-microbial activities of a serine protease inhibitor from honeybee (Apis cerana) venom.

Bee venom contains a variety of peptide constituents, including low-molecular-weight protease inhibitors. While the putative low-molecular-weight serine protease inhibitor Api m 6 containing a trypsin inhibitor-like cysteine-rich domain was identified from honeybee (Apis mellifera) venom, no anti-fibrinolytic or anti-microbial roles for this inhibitor have been elucidated. In this study, we identified an Asiatic honeybee (A. cerana) venom serine protease inhibitor (AcVSPI) that was shown to act as a microbial serine protease inhibitor and plasmin inhibitor. AcVSPI was found to consist of a trypsin inhibitor-like domain that displays ten cysteine residues. Interestingly, the AcVSPI peptide sequence exhibited high similarity to the putative low-molecular-weight serine protease inhibitor Api m 6, which suggests that AcVSPI is an allergen Api m 6-like peptide. Recombinant AcVSPI was expressed in baculovirus-infected insect cells, and it demonstrated inhibitory activity against trypsin, but not chymotrypsin. Additionally, AcVSPI has inhibitory effects against plasmin and microbial serine proteases; however, it does not have any detectable inhibitory effects on thrombin or elastase. Consistent with these inhibitory effects, AcVSPI inhibited the plasmin-mediated degradation of fibrin to fibrin degradation products. AcVSPI also bound to bacterial and fungal surfaces and exhibited anti-microbial activity against fungi as well as gram-positive and gram-negative bacteria. These findings demonstrate the anti-fibrinolytic and anti-microbial roles of AcVSPI as a serine protease inhibitor.

The common dietary flavonoid myricetin attenuates liver fibrosis in carbon tetrachloride treated mice.

SCOPE: Myricetin is found in most berries, vegetables, and various medicinal herbs, which has been reported to possess various bio-activities. However, the role of myricetin on liver fibrosis remains to be elucidated. METHODS AND RESULTS: Hepatic stellate cell (HSC) line CFSC-8B was stimulated by transforming growth factor ß1 (TGF-ß1) or platelet-derived growth factor BB (PDGF-BB) to induce liver fibrosis in vitro. The results showed that myricetin significantly ameliorated TGF-ß1- or PDGF-BB-induced HSCs activation, cell migration, and extracellular matrix production; blocked TGF-ß1-induced phosphorylation of Smad2, P38, extracellular signal-regulated kinase (ERK), and protein kinase B (Akt); and downregulated PDGF-BB stimulated phosphorylation of extracellular signal-regulated kinase and Akt in HSCs in a dose-dependent manner. Meanwhile, the carbon tetrachloride (CCl4 ) induced mouse model has been used to study antifibrosis role of myricetin in vivo. Our data demonstrated that myricetin suppressed α-smooth muscle actin and collagen type I deposition and blocked phosphorylation of Smad2, mitogen-activated protein kinases, and Akt in CCl4 -treated mice. CONCLUSION: Myricetin inhibits the activation of HSCs and ameliorates CCl4 -induced liver fibrosis in mice and may serve as a potential therapeutic agent in the treatment of liver fibrosis.

α2-Antiplasmin is involved in bone loss induced by ovariectomy in mice.

The mechanism of postmenopausal osteoporosis is not fully understood. α2-Antiplasmin (α2-AP) is the primary inhibitor of plasmin in the fibrinolytic system, but is known to have activities beyond fibrinolysis. However, its role in bone metabolism and the pathogenesis of osteoporosis remains unknown. In the current study, we therefore examined the effects of α2-AP deficiency on ovariectomy (OVX)-induced bone loss by using wild-type and α2-AP-deficient mice. Quantitative computed tomography analysis revealed that α2-AP deficiency blunted OVX-induced trabecular bone loss in mice. Moreover, α2-AP deficiency significantly blunted serum levels of bone-specific alkaline phosphatase, cross-linked C-telopeptide of type I collagen, and interleukin (IL)-1ß elevated by OVX. α2-AP treatment elevated the levels of IL-1ß and tumor necrosis factor (TNF)-α mRNA in RAW 264.7 cells, although it suppressed osteoclast formation induced by receptor activator of nuclear factor-κB ligand. α2-AP treatment activated ERK1/2 and p38 MAP kinase pathways in RAW 264.7 cells, and these MAP kinase inhibitors antagonized the levels of IL-1ß mRNA elevated by α2-AP. The data demonstrate that α2-AP is linked to bone loss due to OVX, through a mechanism that depends in part on the production of IL-1ß and TNF-α in monocytes.

Haemostatic and inflammatory alterations in familial hypercholesterolaemia, and the impact of angiotensin II infusion.

INTRODUCTION: We examined potential prothrombotic and proinflammatory effects of angiotensin II in 16 otherwise healthy familial hypercholesterolaemia subjects and 16 matched controls. METHODS: Markers of fibrinolysis, thrombin generation and inflammation were assessed in plasma before, during and 1h after a 3h intravenous infusion of angiotensin II. In addition, placebo experiments with saline infusion were carried out. RESULTS: Baseline plasminogen activator inhibitor type-1 activity and plasmin-antiplasmin-complex concentrations were similar in FH and controls, as were interleukin-6, leukocyte counts and C-reactive protein. Fibrinogen levels were higher in FH, and we observed a greater thrombin generating potential in FH (calibrated automated thrombogram), but no signs of elevated thrombin generation in vivo (prothrombin fragment 1+2). During angiotensin infusion plasminogen activator inhibitor type-1 activity decreased and plasmin-antiplasmin-complex concentrations increased similarly in FH and controls. Total and maximal amount of thrombin generated was unchanged, as were prothrombin-fragment-1+2 levels. Interleukin-6 and leukocyte counts increased similarly in both groups during angiotensin infusion, while fibrinogen tended to increase in FH and increased in controls. During saline infusion plasminogen activator inhibitor type-1 activity and prothrombin fragment 1+2 concentrations fell, whereas other markers were unchanged. CONCLUSIONS: FH exhibits an increased thrombin generation potential, an intact fibrinolysis, and has no convincing signs of inflammation. Angiotensin has proinflammatory effects, and might have minor profibrinolytic and procoagulatory effects.

Can divergent plasmin-antiplasmin-carbon monoxide interactions in young, healthy tobacco smokers explain the 'smoker's paradox'?

In the setting of acute myocardial infarction, decreases in early/late mortality, reocclusion after thrombolysis, and restenosis rate after percutaneous intervention are lower in smokers - this phenomenon has been designated as the 'smoker's paradox'. These benefits of smoking, however, are abrogated by stent placement. We hypothesized that fibrinolytic vulnerability would change in response to smoking, and that inhaled carbon monoxide may play a role. Smoking patients (n = 20, two cigarettes consumed within 90 min, average carboxyhemoglobin concentration of 5%) had plasma collected and normal individual (n = 20) plasma was also obtained. Thrombelastographic analyses conducted with addition of tissue-type plasminogen activator revealed that with the exception of the rate of thrombus generation, there was little difference in fibrinolytic kinetics between normal and smoking individuals. Addition of exogenous carbon monoxide resulted in diminished fibrinolytic response to the same extent in both groups. Subanalyses demonstrated that the smoking cohort had both hyperfibrinolytic and hypofibrinolytic patients as defined by confidence interval (5-95%) values generated from normal individuals. Addition of carbon monoxide reduced hyperfibrinolytic parameter values by 80% in smokers, whereas only a 17% decrease in hypofibrinolytic values changed. Our investigation suggests that 'smoker's paradox' involves a marked change in the character of the plasmin-antiplasmin-carbon monoxide interaction. Further investigation will be required to further define the molecular mechanism responsible for the 'smoker's paradox'.

A spider-derived Kunitz-type serine protease inhibitor that acts as a plasmin inhibitor and an elastase inhibitor.

Kunitz-type serine protease inhibitors are involved in various physiological processes, such as ion channel blocking, blood coagulation, fibrinolysis, and inflammation. While spider-derived Kunitz-type proteins show activity in trypsin or chymotrypsin inhibition and K(+) channel blocking, no additional role for these proteins has been elucidated. In this study, we identified the first spider (Araneus ventricosus) Kunitz-type serine protease inhibitor (AvKTI) that acts as a plasmin inhibitor and an elastase inhibitor. AvKTI possesses a Kunitz domain consisting of a 57-amino-acid mature peptide that displays features consistent with Kunitz-type inhibitors, including six conserved cysteine residues and a P1 lysine residue. Recombinant AvKTI, expressed in baculovirus-infected insect cells, showed a dual inhibitory activity against trypsin (K(i) 7.34 nM) and chymotrypsin (K(i) 37.75 nM), defining a role for AvKTI as a spider-derived Kunitz-type serine protease inhibitor. Additionally, AvKTI showed no detectable inhibitory effects on factor Xa, thrombin, or tissue plasminogen activator; however, AvKTI inhibited plasmin (K(i) 4.89 nM) and neutrophil elastase (K(i) 169.07 nM), indicating that it acts as an antifibrinolytic factor and an antielastolytic factor. These findings constitute molecular evidence that AvKTI acts as a plasmin inhibitor and an elastase inhibitor and also provide a novel view of the functions of a spider-derived Kunitz-type serine protease inhibitor.

Early detection of venous thromboembolism in patients with neuroepithelial tumor: efficacy of screening with serum D-dimer measurements and Doppler ultrasonography.

The efficacy of combined serum D-dimer level measurement and Doppler ultrasonography of the lower extremity was investigated for screening of venous thromboembolism (VTE) in patients with neuroepithelial tumor. Eighty-one patients with neuroepithelial tumor were prospectively studied. All patients underwent measurement of serum D-dimer levels and Doppler ultrasonography of the lower extremity. The serum D-dimer level was measured every week, and Doppler ultrasonography was performed two and two weeks after surgery, then every two weeks until discharge, or every two weeks for patients who did not undergo surgery. If the serum D-dimer level increased over 10.0 µg/ml, Doppler ultrasonography or computed tomography was performed to detect VTE. VTE occurred in 12 (14.8%) patients (seven males and five females; age 34-75, mean 59.0 years). Only one patient was symptomatic, whereas 11 patients identified by the screening were without symptoms. Five patients were treated with anticoagulant therapy, one with prophylactic inferior vena cava filter placement with anticoagulant therapy, and the other six were closely followed up without medication. No patient died of pulmonary embolism. Serial Doppler ultrasonography showed thrombus regression or organization and no thrombus extension. The maximum serum D-dimer value was significantly higher in patients with VTE than in those without VTE (mean 14.5 vs. 3.46 µg/ml, P < 0.001). The D-dimer cutoff value of 5.4 µg/ml could be used to identify VTE with 83% sensitivity and 84% specificity. The combination of sequential serum D-dimer measurement and Doppler ultrasonography of the lower extremity is an efficient and non-invasive procedure for identifying asymptomatic VTE in patients with neuroepithelial tumor.

Non-functioning adrenal incidentalomas are associated with elevated D-dimer levels.

AIM: Although the majority of adrenal incidentalomas (AI) are non-functioning, studies evaluating metabolic disturbances in this particular group are limited. The objective of this study is to investigate metabolic syndrome components and levels of plasma von Willebrand factor (VWF), fibrinogen, and D-dimer in subjects with non-functioning AI. SUBJECTS AND METHODS: Forty-five subjects without clinical and subclinical findings of hypercortisolism or other adrenal gland disorders and 37 healthy controls were enrolled. The patients and controls underwent hormonal evaluation including morning cortisol, ACTH, post-dexamethasone suppression test (DST), morning cortisol, DHEAS, and urinary free cortisol. Anthropometric and metabolic parameters and body composition were assessed and fibrinogen, D-dimer, and VWF were measured. RESULTS: When compared with healthy controls, subjects with AI had significant elevations in several metabolic and anthropometric parameters, uric acid, post-DST cortisol, and D-dimer. When compared with body mass index-matched controls, blood pressure (p=0.004), uric acid (p=0.009), post-DST cortisol (p=0.014), and D-dimer (p=0.045) remained significantly elevated. We demonstrated weak correlations between D-dimer and other metabolic and anthropometric variables. Morning cortisol was demonstrated as an independent variable associated with homeostasis model assessment levels in subjects with AI (beta=410, p=0.004). CONCLUSION: Individuals with clinically and hormonally inactive adrenal adenomas feature insulin resistance and a variety of metabolic disturbances. The subtle cortisol autonomy seems to be associated with insulin-resistant state. D-dimer elevation in AI group was a consequence of insulin-resistant state associated with subtle cortisol autonomy rather than a direct effect of cortisol secretion.

Prediction of deep vein thrombosis after total knee arthroplasty with preoperative D-dimer plasma measurement.

BACKGROUND: Despite prophylaxis, deep vein thrombosis (DVT) still occurs frequently after elective knee surgery. Hence, it would be helpful if the high-risk DVT patients could be identified before surgery so the adequate prophylaxis could be given. A normal plasma D-dimer level effectively rules out acute DVT patients who were classified as having low clinical probability. In many studies, one coagulation activation marker was measured to observe their role in preoperative prediction ofDVT after major hip or knee surgery. In this study, the preoperative plasma level of D-dimer in patients undergoing total knee arthroplasty (TKA) was collected, and correlated with the results of postoperative venography OBJECTIVE: To determine whether levels of D-dimer in plasma, taken two weeks preoperatively, predicts the development of DVT in patients undergoing TKA. MATERIAL AND METHOD: Fifty-nine consecutive patients undergoing TKA were seen in a preoperative clinic two weeks prior the surgery and had blood taken for measurement of plasma D-dimer. After surgery, they did not receive prophylaxis anticoagulant. Ascending contrast venography of both lower extremities was performed in all cases between the 6th-l0th postoperative day or earlier if clinical symptoms occurred. RESULTS: Plasma D-dimer was measured preoperatively in 59 patients undergoing TKA. DVT was detected by venography in 31 (53%) patients. At a cutoff or 500 ng/ml, the sensitivity, specificity, positive and negative predictive values of the preoperative D-dimer concentration for the development of subsequent DVT were 58%, 46%, 55%, and 50%, respectively. CONCLUSION: The results of the present study suggested that preoperative plasma measurement of D-dimer concentration is not useful for predicting DVT in patients undergoing TKA.

High dietary menaquinone intake is associated with reduced coronary calcification.

BACKGROUND: Dietary vitamin K is thought to decrease risk of cardiovascular disease by reducing coronary calcification, but inconsistent results are reported. This may be due to different effects of vitamin K(1) (phylloquinone) and vitamin K(2) (menaquinone, MK), but few studies included both. METHODS: We investigated the association of intake of phylloquinone and menaquinone, including its subtypes (MK4-MK10), with coronary calcification in a cross-sectional study among 564 post-menopausal women. Phylloquinone and menaquinone intake was estimated using a food-frequency questionnaire. RESULTS: Sixty-two percent (n=360) of the women had coronary calcification based on 1.5-mm thick slices. Phylloquinone intake was not associated with coronary calcification with a relative risk (RR) of 1.17 (95%-confidence interval: 0.96-1.42; p(trend)=0.11) of the highest versus lowest quartile. Menaquinone intake was associated with decreased coronary calcification with an RR of 0.80 (95%-CI: 0.65-0.98; p(trend)=0.03). CONCLUSION: This study shows that high dietary menaquinone intake, but probably not phylloquinone, is associated with reduced coronary calcification. Adequate menaquinone intakes could therefore be important to prevent cardiovascular disease.

Molecular and functional characterization of drug-metabolizing enzymes and transporter expression in the novel spontaneously immortalized human hepatocyte line HC-04.

In toxicological research, immortalized human hepatocytes provide a useful alternative to primary hepatocytes because interindividual variability in the expression of drug-metabolizing enzymes and drug transporters can largely be eliminated. However, it is essential that the cell line retain the original phenotype. The purpose of this study was to characterize a novel spontaneously immortalized human hepatocyte cell line, HC-04, with respect to the transcript and functional protein expression profile for the major drug-metabolizing enzymes and transmembrane transporters. HC-04 cells retained hepatocyte-specific function including albumin production and ornithine transcarbamoylase and glucose-6-phosphatase activity. Most of the major CYP forms were expressed at basal levels and responsive to inducing agents. In particular, CYP3A4 was expressed abundantly, and HC-04 cells were able to metabolize the CYP3A4 probe, midazolam, at a rate similar to primary human hepatocytes. Furthermore, the major human sulfotransferase and UDP-glucuronosyltransferase forms, as well as members of the ABC and SLC transporter superfamilies, nuclear receptors, and hepatic transcription factors were also expressed. HC-04 cells readily responded to standard hepatotoxicants that are dependent on CYP-mediated bioactivation, while another, tumor-derived cell line remained refractory to the drug challenge. Collectively, HC-04 cells provide a reliable, stable, and reproducible model for biomechanistic studies in drug toxicology.

[Vitamin K-controlled diet: problems and prospects]. / La dieta controllata in vitamina K: problemi e prospettive.

Different natural (phylloquinone and menaquinone) and synthetic (menadione) compounds carry out the same action of Vitamin K in the human body. Vitamin K is a substrate for the enzyme catalysing the posttranslational conversion of specific glutamyl residues to gamma-carboxyglutamyl residues in certain proteins connected with the coagulation (Factors II, VII, IX, X), the anticoagulation (Proteins C and S) and other organic functions (osteocalcin). Foods rich in Vitamin K (1/4) and the action of gut bacteria (3/4) can give rise to changes in Vitamin K status. Dietary factors, alterations of gut bacteria or/and troubles in the absorption of this vitamin can cause a lack, which at first interferes in the normal hemostatic function and later on it leads to modifications in the bone structure. Therefore, it is necessary to pay a lot of attention to dietary intake, adequacy, bioavailability, absorption and metabolism of Vitamin K and compounds with an action similar to it for understanding the signs of lack, choosing the most suitable therapy and managing accurately the coumarin-based oral anticoagulants.

Vitamin K, bone turnover, and bone mass in girls.

BACKGROUND: Vitamin K has been suggested to have a role in bone metabolism, and low vitamin K intake has been related to low bone density and increased risk of osteoporotic fracture. OBJECTIVE: The objective of this study was to determine whether phylloquinone (vitamin K(1)) intake and biochemical indicators of vitamin K status are related to bone mineral content (BMC) and markers of bone formation and bone resorption in girls. DESIGN: Vitamin K status [plasma phylloquinone concentration and percentage of undercarboxylated osteocalcin (%ucOC)] was measured at baseline in a study of 245 healthy girls aged 3-16 y. Cross-linked N-telopeptide of type 1 collagen (NTx) breakdown, osteocalcin, and bone-specific alkaline phosphatase were measured to reflect bone resorption and formation. BMC of the total body, lumbar spine, and hip and dietary phylloquinone intake were measured annually for 4 y. RESULTS: Phylloquinone intake (median: 45 microg/d) was not consistently associated with bone turnover markers or BMC. Better vitamin K status (high plasma phylloquinone and low %ucOC) was associated with lower bone resorption and formation. Plasma phylloquinone was inversely associated with NTx and osteocalcin concentrations (P < 0.05), and %ucOC was positively associated with NTx and bone-specific alkaline phosphatase concentrations (P < 0.05). Indicators of vitamin K status were not consistently associated with current BMC or gain in BMC over the 4-y study period. CONCLUSIONS: Better vitamin K status was associated with decreased bone turnover in healthy girls consuming a typical US diet. Randomized phylloquinone supplementation trials are needed to further understand the potential benefits of phylloquinone on bone acquisition in growing children.

Binding and inhibition of Cdc25 phosphatases by vitamin K analogues.

A synthetic K vitamin analogue, 2-(2-mercaptothenol)-3-methyl-1,4-naphthoquinone or Cpd 5, was previously found to be a potent inhibitor of cell growth [Nishikawa et al., (1995) J. Biol. Chem. 270, 28304-28310]. The mechanisms of cell growth were hypothesized to include the inactivation of cellular protein tyrosine phosphatases, especially the Cdc25 family [Tamura et al. (2000) Cancer Res. 60, 1317-1325]. In this study, we synthesized PD 49, a new biotin containing Cpd 5 derivative, to search for evidence of direct interaction of these arylating analogues with Cdc25A, Cdc25B, and Cdc25C phosphatases. PD 49 was shown to directly bind to GST-Cdc25A, GST-Cdc25B, their catalytic fragments, and GST-Cdc25C. The binding could be competed with excess glutathione or Cpd 5, and a cysteine-to-serine mutation of the catalytic cysteine abolished binding. This was consistent with an involvement in binding of cysteine in the catalytic domain. This interaction between PD 49 and Cdc25 also occurred in lysates of treated cells. PD 49 also bound to protein phosphatases other than Cdc25. We found that the new analogue also inhibited Hep3B human hepatoma cell growth. This growth inhibition involved ERK1/2 phosphorylation and was inhibited by a MEK antagonist. The results demonstrate a direct interaction and binding between this growth-inhibiting K vitamin derivative with both purified as well as with cellular Cdc25A, Cdc25B, and Cdc25C.

Changes in peritoneal coagulation and fibrinolysis after discontinuation of chronic peritoneal dialysis.

OBJECTIVES: To study changes in peritoneal function after transfer from chronic peritoneal dialysis (CPD) to hemodialysis (HD), especially the effects on peritoneal coagulation, fibrinolytic markers, and mesothelium. DESIGN: Prospective observational study. SETTING: A tertiary-care university hospital. PATIENTS: Nine patients who transferred from CPD to HD were enrolled in the study after giving fully informed consent. METHODS: After transfer to HD, the peritoneal cavity was lavaged with low glucose PD solution once per day through PD catheters left in place. Thrombin-antithrombin III complex (TAT) was measured serially as a marker of peritoneal coagulation. As fibrinolytic markers, fibrinogen/fibrin degradation products (FDP) and plasmin-alpha2-antiplasmin complex (PIC) were assessed. Cancer antigen 125 (CA125) was measured as a marker of mesothelial cell mass. RESULTS: Levels of peritoneal TAT and FDP were much higher than plasma levels, indicating high local fibrin turnover. Transfer to HD induced a significant fall in mean peritoneal TAT, from 115.8 +/- 52.1 to 60.7 +/- 21.8 ng/mL, p < 0.05. Except for 1 patient with a 20-fold increase, mean peritoneal FDP decreased significantly, from 43.6 +/- 11.1 to 19.6 +/- 3.5 microg/mL, p < 0.05. Mean peritoneal PIC increased significantly, from 1.9 +/- 0.4 to 3.9 +/- 0.6 microg/mL, p < 0.05. Peritoneal CA125 increased from 156.4 +/- 57.3 to 1426.2 +/- 389.4 U/mL, p < 0.05. CONCLUSIONS: Peritoneal fibrin turnover was accelerated on CPD and stabilized after transfer to HD. Transfer to HD also induced mesothelial regeneration.

Novel effect of vitamin K(1) (phylloquinone) and vitamin K(2) (menaquinone) on promoting nerve growth factor-mediated neurite outgrowth from PC12D cells.

The nerve growth factor (NGF)-potentiating effect of K vitamins on PC12D cells was investigated. Treatment of PC12D cells with vitamin K(1) or K(2) in the presence of NGF significantly enhanced the proportion of neurite-bearing cells and acetylcholinesterase activity compared with NGF treatment alone. The K vitamins-enhanced neurite outgrowth on PC12D cells was completely blocked by a protein kinase A (PKA) inhibitor or mitogen-activated protein kinase (MAPK) kinase inhibitor PD98059, whereas a protein kinase C inhibitor chelerythrine chloride did not significantly inhibit the enhancing effect of the K vitamins. These results suggest that the K vitamins enhance neurite outgrowth via the activation of PKA and MAPK-mediated signaling pathways in PC12D cells.