[Test particles of medical devices by Coulter Multisizer].

Introduced the "particles" item testing progress and some notes, using Coulter Multisizer, about medical devices and drugs wrapper, with an expectation of some help for the "particles" item tests in the solution in these area.

Exogenous angiotensin (1-7) directly inhibits epithelial-mesenchymal transformation induced by transforming growth factor-ß1 in alveolar epithelial cells.

Accumulating evidence indicates that angiotensin (1-7) [Ang-(1-7)] protects against idiopathic pulmonary fibrosis (IPF) in animal experiments. However, whether Ang-(1-7) effectively inhibits epithelial-mesenchymal transition (EMT) induced by transforming growth factor-ß1 (TGF-ß1) remains unclear. The aim of this study is to examine the eff ;ects of Ang-(1-7) on TGF-ß1-induced EMT in human alveolar epithelial cells. We found that angiotensin-converting enzyme 2 (ACE2) /Ang-(1-7)/MasR were decreased in the lungs of mice with IPF induced by bleomycin, and were negatively correlated with Tgfb1 mRNA expression. In vitro, our data showed that exogenous Ang-(1-7) restored the expression of E-cadherin and decreased the expressions of α-SMA and Vimentin induced by TGF-ß1 in A549 cells. Ang-(1-7) also reduced TGF-ß1-induced migration and synthesis of the extracellular matrix, such as collagen Ⅰ and collagen Ⅲ. Mechanistically, we observed that Ang-(1-7) directly inhibited TGF-ß1-induced phosphorylation of Smad2 and Smad3, and suppressed the expression of the downstream target gene of TGF-ß1-Smad signaling, including ZEB1, ZEB2, TWIST, and SNAIL1. Additionally, phosphorylation of mTOR induced by TGF-ß1 also been suppressed by Ang-(1-7) treatment in A549 cells. Interestingly, we found that TGF-ß1 strongly suppressed the expression of ACE2 in A549 cells through inhibiting SIRT1. In conclusion, our findings indicate that Ang-(1-7) directly inhibits TGF-ß1-induced EMT in alveolar epithelial cells via disruption of TGF-ß1-Smad signaling pathway, contributing to the protective effect against IPF.

Levels of plasma des-gamma-carboxy protein C and prothrombin in patients with liver diseases.

AIM: To study the plasma des-gamma-carboxy protein C activity, antigen and prothrombin levels in patients with liver diseases and their clinical significance. METHODS: Plasma protein C activity (PC:C) was detected by chromogenic assay and antigen (PC:Ag) and des-gamma-carboxy protein C (DCPC) were detected by ELISA. Total prothrombin and unabsorbed prothrombin in plasma were detected by ecarin chromogenic assay. RESULTS: Compared with the control, the levels of PC:C and PC:Ag in patients with hepatocellular carcinoma (HCC) and liver cirrhosis (LC) were lower (PC:C: 104.65+/-23.0%, 62.50+/-24.89%, 56.75+/-20.14%, PC:Ag: 5.31+/-1.63 microg/mL, 2.28+/-1.15 microg/mL, 2.43+/-0.79 microg/mL, P<0.05). The levels of PC:Ag in patients with acute viral hepatitis (AVH) also was lower (2.98+/-0.91 microg/mL, P<0.01), but PC:C was close to the control (93.76+/-30.49%, P>0.05). The levels of DCPC in patients with HCC were remarkably higher (0.69+/-0.29 microg/mL, 1.18+/-0.63 microg/mL, 0.45+/-0.21 microg/mL, P<0.05) and its average was up to 50% of total PC:Ag. But those of DCPC in patients with AVH were not significantly different from the control. The levels of total prothrombin were lower in patients with LC, but higher in patients with HCC. The levels of unabsorbed prothrombin were predominantly higher than those of other groups. CONCLUSION: PC:C and PC:Ag in patients with liver diseases (except PC:C in AVH) were lower. The total prothrombin was lower in patients with LC. The higher level of unabsorbed prothrombin may be used as a scanning marker for HCC. DCPC may be used as a complementary marker in the diagnosis of HCC.

[Observation on tissue factor pathway during the onset of acute cerebral infarction].

OBJECTIVE: To establish the possible relationship between some coagulation factors and the onset of acute cerebral infarction (ACI). METHODS: The study population consisted of 71 patients with ACI confirmed by CT and 50 age-matched healthy volunteers. Blood samples were obtained during the onset period of ACI. Tissue factor (TF) and tissue factor pathway inhibitor (TFPI) activity in plasma were assayed with the chromogenic assay. Plasma TF and TFPI antigen were measured with enzyme linked immunoadsorbent assay (ELISA). Plasma F VII coagulation activity (F VII: C) and F VIII coagulation activity (F VIII: C) were developed in the one-stage system. Plasma prothrombin (FII) was determined with Ecarin assay. Plasma fibrinogen (Fbg) was measured with thrombin assay. Plasma antithrombin III activity (ATIII) was determined using heparin cofactor activity assay. RESULTS: Compared with the control, plasma TF activity and antigen in patients with ACI were significantly higher (both P<0.05). But plasma TFPI activity and antigen were remarkably lower in the ACI group (both P<0.05). Plasma F VII: C was significantly higher (P<0.01), and F VIII: C was markedly lower (P<0.05). Plasma FII was remarkably higher (P<0.01). Similarly the Fbg was significantly higher in the ACI than that in the control group (P<0.01), whereas ATIII was significantly lower (P<0.01). CONCLUSION: The initiation of TF pathway is contributed to the onset of ACI and the blood is in hypercoagulable state during the early period of ACI.

[Effects of tetramethylpyrazine on thrombin-induced tissue factor expression in vascular endothelial cells].

OBJECTIVE: To observe the effects of tetramethylpyrazine (TMP) on tissue factor (TF) expression induced by thrombin in human umbilical vein endothelium derived cell line ECV304. METHODS: The changes in the total cellular procoagulant activity (PCA) of ECV304 cells exposed to thrombin were observed with one-stage clotting assay. TF mRNA expression in the exposed cells was examined using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: ECV304 cells stimulated with increasing concentrations of thrombin (1.25-20 U/ml) showed a gradual increase of PCA (r=0.9602, P<0.01). The application of FVII-deficient plasma and the monoclonal antibody of TF confirmed that the PCA of the cells mediated by TF activity. TMP at 125-1000 microg/ml alone did not affect TF expression in ECV304 cells (P>0.20), TMP administered 30 min prior to thrombin exposure showed a significant concentration-dependent inhibitory effect on the increments of PCA (r=-0.9644, P<0.01) and TF mRNA expression (r=-0.9576, P<0.05) in ECV304 cells, and 1000 microg/ml TMP produced the strongest effect. In ECV304 cells stimulated with thrombin for 4, 6, 8, 10 and 12 h, TMP administration significantly inhibited the thrombin-induced PCA, and the effect was especially obvious at 8 h following thrombin exposure (P<0.05). CONCLUSION: Thrombin induces TF expression in vascular endothelial cells, and this effect can be inhibited by TMP at the mRNA level.

[Effect of angiotensin II on tissue factor expression in human peripheral blood monocytes and its mechanisms].

OBJECTIVE: To elucidate the effect of angiotensin II (AngII) on the expression of tissue factor (TF) by monocytes and its mechanisms. METHODS: Monocytes were isolated from healthy volunteers by Ficoll-Hypaque gradient and Percoll, and cultured in RPMI-1640. Procoagulant activity (PCA) was determined by one-stage clotting method, TF antigen by ELISA. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to detect the TF gene mRNA. The levels of IkappaBalpha was detected by Western blot. Electrophoretic mobility shift assays (EMSA) were performed to evaluate the activity of NF-kappaB. RESULTS: AngII (10(-9) - 10(-7) mol/L) significantly increased monocyte PCA, TF antigen and TF mRNA expression in a dose and time dependent manner. Losartan (10(-6) - 10(-5) mol/L) significantly inhibited the effects of AngII on TF activity, antigen and mRNA expression in a dose-dependent effects. Staurosporine (2.5 x 10(-7) mol/L) and genistein (4 x 10(-5) mol/L) lowered TF level of monocytes (P < 0.05). Western blot analysis revealed that after exposure to AngII (10(-7) mol/L), IkappaBalpha level decreased at 15 min, reached nadir at 60 min, and recovered at 180 min. EMSA showed NF-kappaB binding activity increased at 15 min, reached peak at 60 min, and recovered at 180 min. Pyrrolidine dithiocarbamate (PDTC, 10(-4) mol/L), an inhibitor of NF-kappaB, or AT1R antagonist losartan (10(-5)mol/L) inhibited AngII-induced NF-kappaB translocation. CONCLUSIONS: AngII could induce the expression of TF in human monocytes, and this effect was mediated by AT1R. The PKC pathway played the most important role in AngII-induced TF expression. The activation of NF-kappaB was involved in TF expression in monocytes.

[Changes of tissue factor and tissue factor pathway inhibitor in neonatal jaundice due to infection].

OBJECTIVE: Tissue factor (TF) is an important factor in extrinsic coagulation. Tissue factor pathway inhibitor (TFPI) is a negative regulator of coagulation mediated by TF. Studies on TF and TFPI focus mainly on adult objects, seldom have been done on newborns, especially on sick newborns. The aim of this study was to observe the changes of TF and TFPI in plasma of newborns with infection jaundice and to research the effect of jaundice and infection on the balance of TF and TFPI in newborns. METHODS: The content of TF and TFPI in plasma of 21 jaundiced newborns with infection and 8 jaundiced newborns without infection as control was determined quantitatively with the enzyme-linked immunosorbent assay (ELISA). RESULTS: The content of TFPI and TF in plasma of jaundiced newborn with infection was significantly higher than that of controls [TFPI (21.0 +/- 4.3) vs. (16.2 +/- 1.9) microg/L, P < 0.01; TF (177 +/- 79) vs. (51 +/- 24) ng/L, P < 0.01]. The ratio of TFPI/TF was significantly lower in newborn with infection jaundice than the controls (137 +/- 61 vs. 319 +/- 67, P < 0.01). The 21 jaundiced newborns with infection were divided into the severe hyperbilirubinemia group (serum bilirubin > or = 205.2 micromol/L, n = 10) and the mild hyperbilirubinemia group (serum bilirubin < 205.2 micromol/L, n = 11). There was no significant difference of TFPI level between the severe hyperbilirubinemia group and mild hyperbilirubinemia group (P > 0.05). The TF content in the severe hyperbilirubinemia group was higher than that in the mild hyperbilirubinemia group (216 +/- 79 vs.141 +/- 63, P < 0.01), while the ration of TFPI/TF was lower in the severe hyperbilirubinemia group than in the mild hyperbilirubinemia group (100 +/- 30 vs. 171 +/- 74, P < 0.01). CONCLUSION: Infection might induce imbalance between the coagulation inhibition and activation in newborns. Hyperbilirubinemia can aggravate the imbalance induced by the infection through increasing plasma TF level.