Postoperative changes in plasma tissue-type plasminogen activator and type 1 plasminogen activator inhibitor

The Underestimated Role of Platelets in Severe Infection a Narrative Review

Beyond their role in hemostasis, platelets have emerged as key contributors in the immune response; accordingly, the occurrence of thrombocytopenia during sepsis/septic shock is a well-known risk factor of mortality and a marker of disease severity. Recently, some studies elucidated that the response of platelets to infections goes beyond a simple fall in platelets count; indeed, sepsis-induced thrombocytopenia can be associated with—or even anticipated by—several changes, including an altered morphological pattern, receptor expression and aggregation. Of note, alterations in platelet function and morphology can occur even with a normal platelet count and can modify, depending on the nature of the pathogen, the pattern of host response and the severity of the infection. The purpose of this review is to give an overview on the pathophysiological interaction between platelets and pathogens, as well as the clinical consequences of platelet dysregulation. Furthermore, we try to clarify how understanding the nature of platelet dysregulation may help to optimize the therapeutic approach.

Expression of MMP9, SERPINE1 and miR-134 as prognostic factors in esophageal cancer

Esophageal cancer (EC) is a malignant tumor with a typically poor prognosis for patients. It is well known that certain microRNA (miRNA/miR) genes can regulate other genes responsible for carcinogenesis. In the present study, a group of these genes (miR-21, miR-134, miR-205 and miR-495) and genes connected with cancer-related pathways (MET, MMP9, PDGFA and SERPINE1) were chosen for analysis in order to find a potential correlation between their expression and the clinicopathological factors of EC. Esophageal tumors and adjacent non-cancerous tissue specimens were collected from a total of 63 patients and embedded in paraffin. Commercial arrays were used on KYSE-30, KYSE-150 and KYSE-270 EC cell lines in order to find genes of different expression profiles compared with those acquired from the control Het-1A cell line. Quantitative polymerase chain reaction was used on formalin-fixed, paraffin-embedded samples in order to analyze the expression of the genes chosen in the earlier step. The results were analyzed by the Kruskal-Wallis and Mann-Whitney U tests, Spearman's rank correlation coefficient, Kaplan-Meier methods and the long-rank test. Only miR-495 was not expressed in the analyzed samples. The expression of MMP9 and SERPINE1 was significantly coefficient with age range (P=0.011 and P=0.044, respectively) according to the Kruskal-Wallis test. The Spearman's rank-order correlation measurement showed that there was a coefficient correlation between age and miR-134 expression. The same measurement demonstrated a correlation between age range and MMP9 expression. The expression of miR-134 and MMP9 were also found to be correlated. In all cases, a value of P<0.049 was recorded. Overall, the present study demonstrated that MMP9, SERPINE1 and miR-134 were the most prognostic genes in Caucasian patients with EC.

Haemostatic activation and inflammatory response after three methods of treatment of great saphenous vein incompetence

OBJECTIVE

The purpose of this study was to compare the activation of haemostasis and inflammatory response after three different methods of treatment of great saphenous vein (GSV) incompetence.

MATERIAL AND METHODS

Forty-five patients with GSV incompetence were assigned to one of the three types of treatment: high ligation and stripping (HL&S), radiofrequency ablation with ClosureFast (RFA) and endovenous laser ablation (EVLA) with 810 nm diode laser with miniphlebectomy if required. Peripheral blood samples were obtained in the morning before the surgery and 24 hours and 10 days after the procedure. The concentrations of C-reactive protein (CRP), D-dimer, prothrombin fragment 1 + 2 (F1 + 2), antigen of tissue plasminogen activator (t-PA) and von Willebrand factor (vWF) antigen and activity of plasminogen activator inhibitor (PAI-1) were determined. The results were statistically analysed with SPSS for Windows 15.0.

RESULTS

Thirty-eight patients completed the study: 13 from RFA, 14 from EVLA and 11 from HL&S group. The baseline data did not differ among groups. There was a significant increase of D-dimer in HL&S group after 24 hours (P = 0.002). The changes in RFA and EVLA groups did not show statistical significance (P = 0.092). PAI-1 decreased in RFA patients after 24 hours (P = 0.02), did not change in EVLA patients, and tended to increase after HL&S (P = 0.08). The highest CRP increase was observed in HL&S group (P = 0.003). No significant changes in F1 + 2, t-PA and vWF were observed in any group of patients at 24 hours. At 10 days, a further significant increase of D-dimer (P = 0.04) and CRP (P = 0.018) concentrations in HL&S but not RFA and EVLA patients was observed.

CONCLUSIONS

Endovenous thermal ablation is associated with significantly less activation of haemostasis and inflammatory response when compared with HL&S.

Stimulated in vivo synthesis of plasminogen activator inhibitor-1 in human adipose tissue

Plasminogen activator inhibitor type-1 (PAI-1) is one of the most important inhibitors of endogenous fibrinolysis. Adipose tissue is a suggested source of the elevated plasma levels of PAI-1 in obesity. The relation between PAI-1 and inflammation is of particular interest, but current knowledge regarding regulation of PAI-1 in adipose tissue is mainly based on animal studies or ex vivo experiments on human cultured adipocytes. So far, no study has described stimulated gene expression and protein synthesis of PAI-1 in vivo in human adipose tissue. We used open heart surgery as a model of acute systemic inflammation. Twenty-two male patients underwent blood sampling and omental and subcutaneous adipose tissue biopsies for gene expression studies before and after surgery. Expression and localisation of PAI-1 antigen was evaluated by immunohistochemistry. After surgery gene expression of PAI-1 increased 27-fold in omental adipose tissue and three-fold in subcutaneous adipose tissue, but no differences were found in tissue-type plasminogen activator (t-PA) mRNA. PAI-1 antigen was localised within endothelial cells and in the adipose tissue interstitium close to vessels. The upregulated gene expression and protein synthesis in adipose tissue was followed by increased concentrations of PAI-1 antigen in plasma. In conclusion, we present for the first time that an acute systemic inflammation in humans increased gene expression and protein synthesis of PAI-1 in adipose tissue and that this increase was most prominent in omental adipose tissue. PAI-1 synthesis in adipose tissue due to acute systemic inflammation may be a link between inflammation and impaired endogenous fibrinolysis.

Early coagulation disorders after severe burn injury: impact on mortality

OBJECTIVE

To evaluate the time course of coagulation markers in the early postburn period and clarify the role of coagulation alterations in organ failure and in mortality prognosis.

DESIGN AND SETTING

This prospective study was conducted in the burn ICU of a tertiary hospital.

PATIENTS

45 patients with severe thermal burn injury.

MEASUREMENTS AND RESULTS

Clinical data and coagulation and fibrinolysis parameters were measured during the first postburn week. The ICU 28-day mortality rate was 33%. Significant differences in the time course of coagulation markers were observed between survivors and nonsurvivors. SOFA score distinguished between patients with overt and nonovert disseminated intravascular coagulation (DIC) during the overall investigation period. Presence of overt DIC was related to mortality (OR=0.1). Antithrombin, protein S, plasminogen activator inhibitor 1, and SOFA score on day 3, protein C on day 5, and thrombin/antithrombin complexes on day 7 revealed a good prognostic value for ICU mortality, according to the area under ROC curves.

CONCLUSIONS

Severe thermal injury is associated with the early activation of coagulation cascade, presence of DIC, organ failure, and increased mortality.

Elevation of plasma free PAI-1 levels as an integrated endothelial response to severe burns

To clarify the role of plasminogen activator inhibitor type 1 (PAI-1) in postburn hypercoagulation, we assayed the plasma levels of tissue-type plasminogen activator (t-PA) antigen, total PAI-1 antigen, and total t-PA-PAI-1 complex in 15 burned patients. The total body surface area of the burn injury ranged from 30 to 80%. Serial blood samples were collected from 12 to 168 h following the thermal injury. The plasma t-PA level and the free PAI-1 level increased significantly in the immediate postburn period, and the percent increase in the latter over the values in the healthy controls was much greater than that of the former. The ratio of the concentrations of t-PA-PAI-1 complex to free PAI-1 decreased throughout the 7 postburn days. The fact that the decreases in this ratio clearly showed no dissociation of the euglobulin fraction suggests that the postburn hypofibrinolysis occurred as a result of increased synthesis of PAI-1. On the other hand, changes in several parameters of the coagulation or fibrinolysis system and in plasma thrombomodulin showed that postburn hypercoagulability is associated with secondary hyperfibrinolysis with no evidence of vascular endothelial injury. The paradoxical coexistence of postburn hyper- and hypofibrinolysis is a good reflection of the character of PAI-1, which is a biphasic protein that is both a functional protein and an acute phase reactant. Thus, increased synthesis of PAI-1 may not enhance postburn hypercoagulability to create a coagulation-dominant type of disseminated intravascular coagulation severe enough to trigger multiple organ dysfunction syndrome. In conclusion, increased synthesis of PAI-1 in the initial postburn period reflects an integrated endothelial response to burn stress, and because it is a functional protein, the concentration of free PAI-1 antigen may be an important index for predicting secondary consumption coagulopathy.

Pulmonary thromboembolism after surgery for esophageal cancer: its features and prophylaxis

We attempt to clarify the problems of pulmonary thromboembolism (PTE), which occurs less frequently in Japan than in the West, regarding its special perioperative management and prophylaxis for PTE after esophagectomy. We studied 26 patients with PTE following esophagectomy among 1023 patients with esophageal cancer between 1984 and 1997. The presence of embolism was confirmed by pulmonary perfusion scintigraphy. The incidence, diagnosis, and other issues of PTE were all reviewed. The incidence of PTE was 2.5%, with patients showing a biphasic early and late onset. The main symptoms were dyspnea in 19 patients and tachycardia in 17. Scintigraphy demonstrated 154 lesions, 35.7% of which were located in the left lower lobe and 25.3% in the right lower lobe. Treatment mainly consisted of the administration of heparin and urokinase. Four of the 26 patients died. Intermittent pneumatic compression (IPC) with the administration of heparin has been used in our department since 1994 to prevent PTE and this has also helped to decrease the incidence from 3.2% to 0.7%. Because the incidence of PTE following esophagectomy is higher than expected, PTE should be considered whenever hypoxemia of some unknown cause is found. Both early diagnosis and treatment are essential. It is also important to prevent PTE by the use of IPC.