Migration of the FDNPP-derived 134Cs and 137Cs along with 226Ra and 228Ra concentrations across the northwestern North Pacific Ocean.

We examined lateral distributions of 134Cs, 137Cs, 226Ra, and 228Ra in the surface seawaters around the Kuril Islands and the Kamchatka Peninsula in the northwestern North Pacific Ocean during June 2014. The sampling area included three water current areas, the Oyashio Current, the current from the Okhotsk Sea, and the coastal current along the east Kamchatka Peninsula. 226Ra and 228Ra distributions differed along the three currents. Low levels of 134Cs were detected in the surface waters of the Oyashio Current (0.09-0.35 mBq/L), but it was <∼0.1 mBq/L at the surface along the other two currents. This indicates that the distribution of Fukushima Dai-ichi Nuclear Power Plant (FDNPP)-derived radiocesium in surface waters off the Kamchatka and along the Kuril Islands is predominantly governed by the Oyashio current system.

Regulatory mechanisms of C4b-binding protein (C4BP)alpha and beta expression in rat hepatocytes by lipopolysaccharide and interleukin-6.

BACKGROUND: C4b-binding protein (C4BP), a multimeric protein structurally composed of alpha chains (C4BPalpha) and a beta chain (C4BPbeta), regulates the anticoagulant activity of protein S (PS). Patients with sepsis have increased levels of plasma C4BP, which appears to be induced by interleukin (IL)-6. However, it is not fully understood how lipopolysaccharide (LPS) and IL-6 affect the plasma C4BP antigen level and C4BPalpha and C4BPbeta expression in hepatocytes. OBJECTIVES: To assess the effect of LPS and IL-6 on plasma C4BP, PS-C4BP complex levels, PS activity, and C4BP expression by rat liver in vivo and on C4BP expression by isolated rat hepatocytes in vitro. RESULTS: Plasma C4BP antigen level transiently decreased from 2 to 12 h after LPS (2 mg kg(-1)) injection, and then it abruptly increased up to 24 h after LPS injection. Plasma C4BP antigen level increased until 8 h after IL-6 (10 microg kg(-1)) injection, and then gradually decreased up to 24 h after IL-6 injection. LPS significantly decreased the protein and mRNA expression of both C4BPalpha and C4BPbeta in rat hepatocytes, and this effect was inhibited by NFkappaB and MEK/ERK inhibitors. IL-6 mediated increase in C4BPbeta expression in rat hepatocytes, which leads to increased plasma PS-C4BP complex level and to decreased plasma PS activity, was inhibited by inhibition of STAT-3. CONCLUSION: LPS decreases both C4BPalpha and C4BPbeta expression via the NFkappaB and MEK/ERK pathways, whereas IL-6 specifically increases C4BPbeta expression via the STAT-3 pathway, causing an increase in plasma PS-C4BP complex, and thus decreasing the anticoagulant activity of PS.

Protein C inhibitor regulates hepatocyte growth factor activator-mediated liver regeneration in mice.

BACKGROUND: We recently reported that human protein C inhibitor (PCI), a major inhibitor of activated protein C (APC), inhibits hepatocyte growth factor activator (HGFA) by forming HGFA-PCI complexes in vitro. In this study, we evaluated whether PCI regulates HGFA-mediated liver regeneration in a human PCI gene transgenic (hPCI-Tg) mouse model. METHODS AND RESULTS: After partial hepatectomy in hPCI-Tg and wild-type (WT) mice, the degree of liver regeneration, protein and mRNA expression of HGFA, proHGF activation, plasma levels of PCI and HGFA-PCI complex, and other markers were evaluated in the remnant liver. We also evaluated the effect of anti-human PCI antibody on liver regeneration, which significantly decreased in hPCI-Tg mice compared to WT mice. HGFA mRNA levels in naive and remnant livers after hepatectomy were the same in both WT and hPCI-Tg mice; however, plasma HGFA levels and HGF activation in the liver were lower in hPCI-Tg than in WT mice. There was no difference in plasma levels of transaminases and inflammatory cytokines. However, sinusoidal congestion and bleeding were detected and the serum hyaluronic acid level was elevated in hPCI-Tg mice, indicating that human PCI aggravates sinusoidal injury by inhibiting the cytoprotective effect of APC. APC decreased thrombin-induced IL-6 production in isolated hepatic nonparenchymal cells (NPCs) in vitro. This impaired liver regeneration was reversed by anti-human PCI antibody treatment in vivo. CONCLUSION: PCI regulates liver regeneration after hepatectomy by forming an HGFA-PCI complex and aggravates hepatic NPC injury by inhibiting the cytoprotective effect of APC. Anti-PCI antibody treatment may be a novel therapy for improving liver regeneration.

Association of epidermal growth factor receptor mutations in lung cancer with chemosensitivity to gefitinib in isolated cancer cells from Japanese patients.

Somatic mutations in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) gene are reported to be associated with clinical responsiveness of lung cancer to gefitinib, an EGFR tyrosine kinase inhibitor. To elucidate the association between somatic mutations and the pharmacological actions of gefitinib, the chemosensitivity of isolated cancer cells from the lungs of Japanese patients to gefitinib was examined by the collagen gel-droplet embedded culture drug sensitivity test in vitro. In 30 specimens isolated from non-small-cell lung cancer patients, mutations were observed in eight tumour specimens (27%) and chemosensitivity to gefitinib was observed in seven specimens (23%). However, somatic mutations were not predominantly associated with chemosensitivity to gefitinib in vitro. Both mutation and chemosensitivity frequencies in this study were higher than those reported in studies from the United States, indicating a possible ethnic difference. Moreover, both frequencies were much higher in females than in males. Since a gender difference in chemosensitivity to gefitinib was observed in isolated cancer cells in vitro, this suggests that gefitinib works in part through the suppression of EGFR signalling, but that other factors, including sex-related factors, may participate in gefitinib action.

Protein C inhibitor directly and potently inhibits activated hepatocyte growth factor activator.

BACKGROUND: Hepatocyte growth factor (HGF) plays an important role in tissue repair and regeneration. HGF activator (HGFA), a factor XIIa-like serine protease, activates HGF precursor to HGF. The precursor of HGFA, proHGFA, is activated by thrombin generated at sites of tissue injury. It is known that protein C inhibitor (PCI), an inhibitor of activated protein C (APC), also inhibits thrombin-thrombomodulin (TM) complex. OBJECTIVES: In the present study we evaluated the effect of PCI on thrombin-catalyzed proHGFA activation in the presence of TM, and on HGFA activity. RESULTS: PCI did not inhibit thrombin-TM-mediated proHGFA activation, but it directly inhibited activated HGFA by forming an enzyme inhibitor complex. The second-order rate constants (m(-1) min(-1)) of the reaction between HGFA and PCI in the presence or absence of heparin (10 U mL(-1)) were 4.3 x 10(6) and 4.0 x 10(6), respectively. The inhibition of HGFA by PCI resulted in a significant decrease of HGFA-catalyzed activation of HGF precursor. Exogenous HGFA added to normal human plasma formed a complex with plasma PCI, and this complex formation was competitively inhibited by APC in the presence of heparin, but very weakly in the absence of heparin. We also demonstrated using recombinant R362A-PCI that Arg362 residue of PCI is important for HGFA inhibition by PCI as judged from the three-dimensional structures constructed using docking models of PCI and HGFA or APC. CONCLUSION: These observations indicate that PCI is a potent inhibitor of activated HGFA, suggesting a novel function for PCI in the regulation of tissue repair and regeneration.

Differential regulation of protein S expression in hepatocytes and sinusoidal endothelial cells in rats with cirrhosis.

BACKGROUND: Liver dysfunction caused by intrasinusoidal microthrombi is frequently observed in patients with cirrhosis after hepatectomy, but the mechanistic pathway remains unknown. OBJECTIVE: In the present study, we evaluated the expression of protein S (PS) in hepatocytes and sinusoidal endothelial cells (SECs) from rats with dimethylnitrosoamine-induced cirrhosis before and after hepatectomy. RESULTS: The plasma level of PS antigen was significantly decreased in cirrhotic rats as compared to control rats treated with vehicle. PS expression was significantly decreased in hepatocytes isolated from cirrhotic rats as compared to controls. In contrast, PS expression was significantly increased in SECs isolated from rats with cirrhosis as compared to controls. Interleukin-6 (IL-6) upregulated the expression of PS in hepatocytes, and tumor necrosis factor-alpha (TNF-alpha) decreased its expression in SECs from both cirrhotic and normal rats. The production of IL-6 and TNF-alpha by Kupffer cells and SECs was decreased in rats with cirrhosis as compared to controls. After hepatectomy, microthrombus formation was markedly enhanced in sinusoids from rats with cirrhosis, and the plasma levels of IL-6 and TNF-alpha were significantly increased in rats with cirrhosis as compared to controls. Furthermore, PS production in SECs was decreased, whereas that in hepatocytes was significantly increased in cirrhotic rats as compared to controls. CONCLUSIONS: These findings suggest that PS expression is differently regulated in hepatocytes and SECs of rats with cirrhosis before and after hepatectomy, that the expression of PS is regulated by locally released inflammatory cytokines, and that decreased expression of PS in SECs may cause liver microthrombus formation, which is frequently observed in patients with cirrhosis after hepatectomy.

Lipopolysaccharide-induced decreased protein S expression in liver cells is mediated by MEK/ERK signaling and NFkappaB activation: involvement of membrane-bound CD14 and toll-like receptor-4.

BACKGROUND: The vitamin K-dependent protein S (PS), mainly synthesized in hepatocytes and endothelial cells, plays a critical role in the anticoagulant activity of plasma. The decreased plasma level of PS in sepsis is associated with thrombotic tendency, but the mechanism is unclear. OBJECTIVES: In the present study, we examined the effect of lipopolysaccharide (LPS) on PS expression in vivo in rat liver, and in vitro in isolated hepatocytes and sinusoidal endothelial cells (SECs) from normal rats. RESULTS: LPS induced a progressive decrease of plasma PS antigen level up to 12 h with a slight recovery at 24 h, and a transient decrease of liver PS mRNA level at 4-8 h with a complete recovery at 24 h. In the in vitro studies, LPS decreased PS antigen and mRNA levels in both hepatocytes and SECs. After LPS treatment, tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) transiently increased in plasma. IL-6 increased the protein expression of PS from hepatocytes, while TNF-alpha decreased it from SECs. LPS increased CD14 in hepatocytes and decreased it in SECs, but did not affect toll-like receptor-4 (TLR-4) expression in both cells. Antirat CD14 and antirat TLR-4 antibodies inhibited LPS-induced NFkappaB activation, and a NFkappaB inhibitor suppressed LPS-induced decreased PS expression in both cells. Furthermore, MEK inhibitor blocked LPS-induced decreased PS expression in both cells. CONCLUSIONS: These findings suggest that LPS-induced decreased PS expression in hepatocytes and SECs is mediated by MEK/ERK signaling and NFkappaB activation and that membrane-bound CD14 and TLR-4 are involved in this mechanism. These findings may explain in part the decreased level of plasma PS and thrombotic tendency in sepsis.

L-arginine improves the symptoms of strokelike episodes in MELAS.

Based on the hypothesis that mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS) are caused by impaired vasodilation in an intracerebral artery, the authors evaluated the effects of administering l-arginine, a nitric oxide precursor. Patients were administered L-arginine intravenously at the acute phase or orally at the interictal phase. L-arginine infusions significantly improved all strokelike symptoms, suggesting that oral administration within 30 minutes of a stroke significantly decreased frequency and severity of strokelike episodes.

Characterization of a novel human protein C inhibitor (PCI) gene transgenic mouse useful for studying the role of PCI in physiological and pathological conditions.

In humans, protein C inhibitor (PCI) is expressed in various tissues and present in many body fluids including plasma and seminal fluid. In rodents, PCI is expressed in reproductive organs only and is absent in plasma. In this study, we characterized the tissue expression and physiological role of PCI in novel human PCI gene transgenic (TG) mice. Northern blot and immunohistochemical analyses demonstrated that human PCI is expressed in liver hepatocytes, renal epithelial cells as well as heart, brain and reproductive organs of the TG mice. This PCI tissue distribution is similar to that found in humans. PCI in plasma of TG mice showed the same immunological and functional properties as human plasma PCI. Next, we evaluated the effect of PCI on coagulation, inflammation and tissue damage in lipopolysaccharide-treated TG mice. The results suggested that PCI efficiently inhibits not only the anticoagulant and anti-inflammatory activities of exogenously injected human activated protein C (APC) but also that of endogenously produced APC in mice with endotoxemia. These findings suggest that PCI exerts a procoagulant and proinflammatory effect by inhibiting APC. We believe our results also show how useful these TG mice may be for assessing the therapeutic effect of human APC in vivo and for evaluating the role of PCI in human physiological and pathological conditions.

[Plasma levels of soluble fibrin in patients with disseminated intravascular coagulation].

Soluble fibrin(SF) is formed in the early-activated state of blood coagulation and quantitative measurement of SF shows high potential as a parameter for the diagnosis of suspected disseminated intravascular coagulation(DIC). The aim of the present study is to evaluate the usefulness of a newly developed SF test utilizing SF specific monoclonal antibody(F405). Among hemopoietic and non-hemopoietic tumor patients, 249 patients with suspected DIC were collected. The SF level showed a good correlation with the DIC score and the SF levels in DIC patients were significantly higher than those in s-DIC and pre-DIC patients. Receiver operating characteristic(ROC) analysis also showed that the specificity and sensitivity of the SF assay were higher than those of thrombin-antithrombin complex(TAT). In conclusion, these results indicate that the SF assay is a highly precise method for the diagnosis and screening of DIC stages.

Mitotic checkpoint protein hsMAD2 as a marker predicting liver metastasis of human gastric cancers.

hsMAD2, the human homologue of mitotic arrest deficient 2 (MAD2), is a key component of the mitotic checkpoint system. Recently, mutations and decreased expression of mitotic checkpoint genes including hsMAD2 have been reported in cancer cell lines with defective mitotic checkpoint. However, the genetic alterations in the genomic hsMAD2 gene have not been determined in gastric cancers. Moreover, the biological implications of the overexpressed hsMAD2 in primary cancers are unknown. In this study, we analyzed 32 primary gastric cancers with polymerase chain reaction (PCR) amplification of all exons, including flanking intronic sequences, of the genomic hsMAD2 gene followed by direct DNA sequencing. We also measured the hsMAD2 protein levels in cancer and normal tissues by semi-quantitative immunoblotting. No mutations were found in the coding sequences, although three single nucleotide polymorphisms (SNPs) were identified in the noncoding sequences in 13 of 32 patients. These SNPs were not associated with either hsMAD2 expression or disease progression. The semi-quantitative western blot analysis showed hsMAD2 was significantly overexpressed in gastric cancer tissues compared with corresponding normal tissues (P < 0.001). The calculated ratio of the hsMAD2 protein in cancer tissue (C) to that in corresponding normal tissue (N) (C / N ratio) was significantly higher in patients with well differentiated adenocarcinoma (P = 0.0274) or with synchronous liver metastasis (P = 0.0025). A C / N ratio greater than 3 was observed more frequently in patients with synchronous liver metastasis. Therefore, C / N ratio > 3 may be clinically important as a predictive indicator for metachronous liver metastasis of gastric cancers.

Change in the concentrations of iron in different size fractions during a phytoplankton bloom in controlled ecosystem enclosures.

To observe micronutrient dynamics in the plankton ecosystem, controlled ecosystem enclosure (CEE) experiments were conducted in Saanich Inlet, B.C., Canada. Two CEEs (2.5 m in diameter, 16 m in length, one for Fe studies and the other for biological studies) were launched for the period 22 July to 5 August 1996 and enriched with 10 µM nitrate and 5.2 nM Fe (13% of total Fe) on day 1. Sampling from three integrated depths, intervals 0-4, 4-8 and 8-12 m, was performed on days 0, 1, 2, 3, 4, 5, 7, 9 and 11. Iron concentrations were measured for five size fractions: >25 µm particles, 2-25 µm particles, 0.2-2 µm particles, 0.2 µm-200 kDa small colloidal particles and <200 kDa soluble species. The sediment in the Fe enclosure was also collected on every sampling day after day 2 and its Fe was determined. Size-fractionated particulate organic carbon and total chlorophyll-a were also analyzed.The Fe in small colloidal particles (200 kDa-0.2 µm) comprised 78% of the traditionally defined dissolved phase (<0.2 µm) on day 1. Of all the size fractions of Fe, the small colloidal particulate fraction decreased most significantly during the phytoplankton bloom. In the dissolved fraction (<0.2 µm), the small colloidal particle fraction comprised 79% of the decrease. The decrease in concentration of Fe in small colloidal particles was larger than that of total Fe from day 1 to day 4. In contrast, the >25 µm Fe particles increased over the same period. These results suggest that Fe in small colloidal particles changed to >25 µm Fe particles during phytoplankton growth. A large amount of Fe was kept in the surface layer with the phytoplankton, and transported to the deep layer by phytoplankton sedimentation, at the end of the bloom. From these results, the small colloidal particulate Fe seems to be the most dynamic size fraction and a high percentage of Fe in small colloidal particles changed to large particles due to chemical/physical aggregation and/or physical adsorption to suspended particles such as phytoplankton cells.

Enhanced absorption of insulin and (Asu(1,7))eel-calcitonin using novel azopolymer-coated pellets for colon-specific drug delivery.

The objective of this study was to estimate colon-specific delivery of insulin and (Asu(1,7))eel-calcitonin using novel azopolymer-coated pellets. In vitro drug-release experiments from the azopolymer-coated pellets containing fluorescein isothiocyanate dextran (MW 4400; FD-4) were carried out by the Japanese Pharmacopoeia (J.P.) XIII rotating basket method with some slight modifications. Little release of FD-4 from the pellets was observed in phosphate buffered saline. However, the release of FD-4 was markedly increased in the presence of rat cecal contents. The intestinal absorption of insulin and (Asu(1,7))eel-calcitonin after oral administration of the azopolymer-coated pellets containing these peptides with camostat mesilate was evaluated by measuring the hypoglycemic and hypocalcemic effects, respectively. A slight decrease in plasma glucose levels was observed following the oral administration of these pellets containing 12.5 IU of insulin compared with the same dose of insulin solution. Camostat mesilate, a protease inhibitor that is incorporated with insulin in these pellets, further decreased the plasma glucose levels in a dose-dependent manner. Similar results were also obtained with the oral administration of pellets containing (Asu(1,7))eel-calcitonin. These findings suggest that azopolymer-coated pellets may be useful carriers for the colon-specific delivery of peptides including insulin and (Asu(1,7))eel-calcitonin.

Plasma levels of activated protein C-protein C inhibitor complex in patients with hypercoagulable states.

Plasma levels of activated protein C (APC)-protein C inhibitor (PCI) were significantly increased in patients with disseminated intravascular coagulation (DIC), thrombotic thrombocytopenic purpura (TTP), acute myocardial infarction (AMI), pulmonary embolism (PE), or deep vein thrombosis (DVT) and in patients undergoing hemodialysis (HD). Plasma levels of APC-alpha(1)-antitrypsin (AT) complex were significantly increased in patients with DIC and in those with TTP. Plasma levels of PCI were significantly decreased in patients with DIC, non-DIC, or TTP and in those undergoing HD. In the pre-DIC stage, the plasma levels of APC-PCI complex were significantly increased but not those of APC-alpha(1)-AT complex. These data suggest that measurements of APC-PCI complex and APC-alpha(1)-AT complex may be useful for the diagnosis of DIC. After treatment of DIC, the plasma levels of APC-PCI complex and APC-alpha(1)-AT complex were significantly decreased, but not those of PCI. Plasma levels of thrombin-antithrombin complex (TAT), plasmin-alpha(2)-plasmin complex (PPIC), D-dimer, and soluble fibrin monomer (SFM) were markedly increased in patients with DIC or pre-DIC and were moderately increased in patients with non-DIC, TTP, AMI, PE, or DVT and in those undergoing HD. The receiving operating characteristic (ROC) analysis showed that SFM and the APC-PCT complex are useful markers for diagnosis of DIC. The specificity of plasma TAT and PPIC levels was low. The positive rate of APC-PCI complex was higher than 90% with DIC, TTP, AMI, PE, and it was higher than 60% with DVT and HD. Since the APC-PCI complex was elevated not only in patients with venous thrombosis but also in those with arterial thrombosis, components of the protein C pathway might be useful markers for the diagnosis of arterial thrombosis.

Detection of methylthioadenosine phosphorylase (MTAP) and p16 gene deletion in T cell acute lymphoblastic leukemia by real-time quantitative PCR assay.

Methylthioadenosine phosphorylase (MTAP) deficiency in tumors can be therapeutically exploited for selective therapy. Many tumors lacking MTAP have been found to homozygously delete the chromosome 9p region containing the p16 tumor suppressor gene. Several methods have been used to detect chromosome 9p deletions in primary tumors. However, the accurate diagnosis of chromosome 9p deletions has been hampered by the presence of contaminating normal cells. In search of an accurate and sensitive diagnostic method, we have developed the real-time polymerase chain reaction assay using the TaqMan chemistry for quantitative detection of MTAP and p16 gene deletions. The assay's feasibility was tested with peripheral blood leukocytes (PBL) from 29 patients with adult T cell leukemia (ATL) previously analyzed with Southern blot analysis and validated on 39 PBL or bone marrow samples from childhood T cell acute lymphoblastic leukemia (T-ALL). Homozygous deletions of MTAP and p16 genes were detected respectively in six (20.7%) and eight (27.6%) of 29 ATL samples and in 15 (38.5%) and 23 (59%) of 39 T-ALL samples. The results correlated well with those of Southern blot analysis. It is of significance that the newly developed method can successfully detect homozygous deletions of these genes in samples containing as low as 33% blast cells. This rapid and sensitive method may be useful in searching for candidates for selective therapy targeting MTAP deficiency.

Increased hemostatic molecular markers in patients undergoing anticoagulant therapy.

We evaluated several molecular markers of hemostasis in 92 patients with hypercoagulable states treated with anticoagulant therapy. In all patients, the average values of the international normalized ratio (INR) were 1.70 +/- 0.50; this increase in INR was not, however, significant in patients under thrombotest (TT) monitoring. There were no thrombotic or severe bleeding complications in these patients during a period of 27 months. Plasma levels of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), D-dimer, and soluble fibrin monomer (sFM) were slightly increased, suggesting that anticoagulant therapy was not completely effective in our Japanese patients based on the values of the TT. The INR was negatively correlated with TT, protein C, and protein S and particularly with TT between 10 and 80%. The range of TT was not correlated with the plasma level of TAT, PPIC, D-dimer, or sFM, but the range of INR was correlated with the plasma level of TAT, D-dimer, and sFM. The percentage of TAT, D-dimer, and sFM within normal range was significantly lower in patients with high INR. These findings show that INR is better than TT for the monitoring of warfarin therapy and that the therapeutic values of INR during the anticoagulant therapy should be > 1.7 in Japanese patients.

Measurement of protein C inhibitor in seminal plasma is useful for detecting agenesis of seminal vesicles or the vas deferens.

Protein C inhibitor (PCI), a plasma serine protease inhibitor of activated protein C, is present at high concentrations in the seminal plasma of normal subjects and is decreased in some infertile patients. We measured the concentrations of PCI, prostate-specific antigen, and fructose in the seminal plasma of infertile patients (n = 125) and of normal subjects (n = 13). We also measured time-dependent changes in the concentrations of PCI and fructose in seminal plasma after ejaculation. A weak correlation was found between the levels of PCI and fructose (r = 0.268, P = 0.016). The PCI level in seminal plasma of patients with seminal vesicle and/or vasal agenesis was significantly lower (P < .01) than in normal subjects. The level of fructose in seminal plasma decreased in vitro in a time-dependent manner after ejaculation, whereas the concentration of PCI was stable at 48 hours after ejaculation. These data suggest that PCI in seminal plasma, as well as fructose, may become one of the markers for agenesis of seminal vesicles and/or the vas deferens.

Bovine protein C inhibitor has a unique reactive site and can transiently inhibit plasmin.

Protein C inhibitor (PCI) regulates the anticoagulant protein C pathway by neutralizing activated protein C and thrombin-thrombomodulin complex in the human hemostatic system. In this study, we cloned a full-length bovine PCI cDNA encoding a putative 19-residue signal peptide and a 385-residue mature protein; this showed 70.6%, 70.6%, 57.5% and 59.6% amino acid sequence homology with the human, rhesus monkey, rat and mouse PCIs, respectively. Bovine PCI mRNA (2.1 kb in size) was expressed strongly in the liver, and moderately in the kidney and testis, but not in other tissues tested. Bovine PCI has a putative reactive site peptide bond, Lys-Ser, that is different from the reactive site sequence (Arg-Ser) of other species' PCI. We found that bovine PCI transiently inhibits bovine plasmin, but not human plasmin. Western blot analysis showed that the reactive site of bovine PCI is cleaved during the course of complex formation with bovine plasmin; degraded PCI is released from the complex gradually concomitant with the recovery of plasmin activity. These findings suggest that bovine PCI plays a role not only in the protein C pathway but also in the fibrinolytic activity of bovine hemostatic system.

Association of oestrogen receptor gene polymorphisms with age at onset of rheumatoid arthritis.

OBJECTIVE: In view of the possible role of oestrogens in the pathogenesis of rheumatoid arthritis (RA), this study investigated the association between oestrogen receptor (OR) gene polymorphisms and RA. METHODS: Pvu II and Xba I restriction fragment length polymorphisms of the OR gene were analysed in 70 male and 240 female patients with RA, and in 300 male and 350 female controls. The absence or presence of restriction sites were represented as P, p (Pvu II) or X, x (Xba I). The distribution of OR genotypes was compared between the RA and control subjects by sex. RA patients were divided into subgroups according to their OR genotypes, then the age at onset, seropositivity, and rheumatoid nodule positivity were compared between the subgroups. RESULTS: The OR genotype frequency of distribution did not have significant differences between the male RA and male controls nor between the female RA and female controls. In women with RA, there was a significant difference of age at onset between the subgroups (uncorrected p = 0.047, corrected p = 0.94). Female patients with the OR genotype PPxx (homozygote of Px) tended to have developed RA at a younger age, whereas those with PPXX and ppxx (lack of Px haplotype) developed RA at an older age. In men with RA, there was no association between the OR genotype and age at onset. In seropositivity and rheumatoid nodule positivity, there was no significant difference between subgroups for either sex. CONCLUSIONS: Some variants of the OR gene are related to the onset of RA in women in certain age periods, suggesting the role of the interaction between the OR gene and serum concentrations of oestrogen at the onset of the disease.