Biological mechanisms and individual variation in fibrinolysis after major trauma.

OBJECTIVE: To understand more about the individual variation in the time course of fibrinolysis following major injury and to assess the potential for stratification of trauma patients for tranexamic acid (TXA) therapy. METHODS: A historical dataset (from 2004) was used, consisting of samples from 52 injured patients attended by a medical prehospital system. Blood samples were taken at the incident scene, on arrival in the emergency department, 2.5 hours after hospital arrival and 5 hours after hospital arrival. From the study database, we extracted values for tissue-type plasminogen activator (tPA; an activator of fibrinolysis), one of the plasminogen activator inhibitors (PAI-1; as a natural inhibitor of fibrinolysis) and D-dimer (as a marker of the extent of fibrinolysis). RESULTS: The changes over time in median tPA and PAI-1 were mirror images, with initial high tPA levels which then rapidly decreased and low initial PAI-1 levels which slowly increased. There were high levels of fibrinolytic activity (D-dimer) throughout. This pattern was present in patients across a broad range of injury severities. CONCLUSIONS: After major trauma, there seems to be an early 'antifibrinolytic gap' with the natural antifibrinolytic system lagging several hours behind the natural profibrinolytics. An early dose of exogenous antifibrinolytic (TXA) might have its effect by filling this gap. The finding that tPA and subsequent clot breakdown (illustrated by D-dimer formation) are raised in a broad range of patients, with little correlation between the initial fibrinolytic response and markers of injury severity, may be the reason that TXA is effective across a broad range of injured patients.

El incremento de la grasa epicárdica en mujeres se asocia a riesgo trombótico / An increase in epicardial fat in women is associated with thrombotic risk

Introducción: En pacientes con enfermedad coronaria se ha observado una disminución de la actividad fibrinolítica y aumento del grosor del tejido adiposo epicárdico. El objetivo del estudio fue determinar la relación entre la grasa epicárdica y la actividad fibrinolítica, midiendo la concentración del inhibidor del activador del plasminógeno tipo-1 (PAI-1). Métodos: Estudio transversal que incluyó a 56 mujeres aparentemente sanas, con edad de 45-60 años. A las participantes se les realizaron mediciones antropométricas y bioquímicas, la actividad fibrinolítica se determinó midiendo PAI-1 por la técnica de ELISA. El grosor epicárdico se evaluó por ecocardiografía transtorácica. Resultados: La concentración de PAI-1 se asoció directamente con el grosor del tejido adiposo epicárdico (r = .475, p = .001), glucosa, triglicéridos, resistencia a la insulina, IMC, tejido adiposo visceral y grasa corporal total. El análisis de regresión multivariado indicó que la grasa epicárdica predice en forma independiente el valor de PAI-1. Conclusiones: Las mujeres con incremento de tejido adiposo epicárdico muestran menor actividad fibrinolítica por presentar niveles aumentados de PAI-1 y, en consecuencia, un posible mayor riesgo trombótico

Introduction: A decrease in fibrinolytic activity and an increase in the thickness of the epicardial adipose tissue have been observed in patients with coronary artery disease. The aim of this study was to determine the association between epicardial adipose tissue and fibrinolytic activity by measuring the concentration of plasminogen activator inhibitor-1 (PAI-1). Methods: A cross-sectional study was conducted on 56 apparently healthy women aged 45 to 60 years. Anthropometric measurements and biochemical determinations were performed on all participants. The fibrinolytic activity was determined by measuring PAI-1 by ELISA. Epicardial thickness was assessed by transthoracic echocardiography. Results: The concentration of PAI-1 was directly associated with the thickness of the epicardial adipose tissue (r = 0.475, P = .001), body mass index (BMI), visceral adipose tissue, insulin resistance, glucose, and HDL-cholesterol. The multivariate regression analysis indicated that epicardial fat independently predicts the concentrations of PAI-1. Conclusions: Women with thicker epicardial adipose tissue have reduced fibrinolytic activity, and consequently greater thrombotic risk

Grasa epicárdica y enfermedad cardiovascular / Epicardial fat and cardiovascular disease

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Effects of addition of tissue-type plasminogen activator in in vitro fertilization medium on bovine embryo development and quality.

Plasminogen activators/Plasmin system plays pivotal role in regulating reproductive functions of mammals. Here, we examined the effects of modification of in vitro fertilization medium (IVF medium) with the addition of tissue-type plasminogen activator (t-PA), on bovine embryo development and quality, assessed by quantification of expression of various genes related to metabolism, oxidation, implantation and apoptosis. In addition, plasminogen activator activity (PAA) and plasminogen activator inhibition (PAI) were measured in the spent media. After conventional IVM, 2016 cumulus-oocyte complexes (COCs) were divided into four groups with modified composition of the IVF medium containing t-PA and/or its inhibitor epsilon-aminocaproic acid (control, t-PA, t-PA+ε-ACA, ε-ACA). Presumptive zygotes were cultured for 8 days in synthetic oviductal fluid (SOF) medium; gene expression studies were carried out on morulae and blastocysts. t-PA alone significantly suppressed cleavage and blastocyst formation rates, but this effect was neutralized by the addition of ε-ACA. PAA in the treated group was significantly reduced by ε-ACA, but without total elimination. Significant differences were detected in the expression of genes related to apoptosis and/or cell cycle arrest (BAX, BCL2L1, KAT2B) between embryos produced in t-PA-modified media and controls, giving an overall notion that the inferior developmental competence of treated embryos may be attributed to apoptotic phenomena induced by t-PA. In conclusion, it appears that excessive t-PA content in the IVF media, suppresses blastocyst formation rate, possibly due to induction of apoptotic phenomena.

[The correlation study of the expression of VEGF with t-PA and PAI expression in plasma and intraocular tissue in proliferative diabetic retinopathy].

OBJECTIVE: To evaluate the correlation between the expression of VEGF with t-PA and PAI expression in plasma aqueous humor and vitreous of proliferative diabetic retinopathy (PDR). METHODS: It was an experimental study. The concentrations of VEGF t-PA and PAI in plasma, aqueous humor and vitreous body in PDR and normal group were detected by ELISA. RESULTS: The levels of VEGF (53.37 ng/L) and PAI (8.00 µg/L) in the plasma of PDR patients were higher than control group, and there was significant statistically difference between them (Z = -3.437, -5.816; P < 0.01). The levels of t-PA (24.32 µg/L) in plasma of PDR patients and control group was no statistically difference between them (Z = -1.715, P = 0.086). The levels of VEGF (335.00 ng/L) t-PA (5.70 µg/L) and PAI (0.63 µg/L) in the aqueous humor of PDR patients were higher than control group, and there was statistically difference between them (Z = -4.805, -1.967, -4.018; P < 0.05). The levels of VEGF (691.69 ng/L) t-PA (13.05 µg/L) and PAI (4.01 µg/L) in the vitreous of PDR patients were higher than control group , and there was statistically difference between them (Z = -2.807, -2.642, -2.230;P < 0.05). Compare the plasma aqueous humor and vitreous of PDR patients. The levels of VEGF is: vitreous>aqueous humor>plasma. The levels of t-PA is: plasma>vitreous>aqueous humor. The levels of PAI is: plasma and vitreous>aqueous humor. The expression of VEGF was highly correlated with t-PA and PAI in plasma aqueous humor and vitreous of PDR (P < 0.05). CONCLUSIONS: VEGF PAI in plasma, VEGF t-PA PAI in aqueous humor and vitreous were increases. The expression of VEGF was positive correlated with t-PA and PAI in plasma aqueous humor and vitreous of PDR.

Efecto de la sensibilidad a la insulina en marcadores de hemostasia tras el consumo de dietas con distintos tipos de grasa en varones jóvenes sanos / Insulin sensitivity regulates haemostatic markers after regular consumption of diets with different types of fat in healthy young men

Introducción. La hemostasia es un proceso complejo que regula la integridad del lecho vascular. La dieta modula la concentración de ciertos marcadores de hemostasis, aunque no está claro si el grado de resistencia a la insulina influye en esta relación. Nuestro objetivo fue investigar si la sensibilidad a la insulina influye en la concentración en ayunas y posprandial de ciertos marcadores de hemostasia (factor VII coagulante [FVIIc]), en el activador tisular del plasminógeno (tPA) y en el inhibidor del activador del plasminógeno (PAI-1), independientemente de la dieta consumida.Métodos. Estudio con diseño aleatorizado y cruzado, en el que 20 varones sanos recibieron 3 dietas, durante 4 semanas cada una, ricas en ácidos grasos monoinsaturados (Medit), saturados (Occid) e hidratos de carbono enriquecida con N3 (HC/N3). Posteriormente, se distribuyó a los participantes en 2 grupos: HOMA elevado (HE) o HOMA bajo (HB), dependiendo de las medianas para cada período de dieta. Se extrajeron determinaciones de FVIIc, tPA y PAI-1 en ayunas y 4 h después de una comida con la misma composición grasa que la seguida en el período previo, y se compararon los 2 grupos anteriores (HB frente a HE).Resultados. Hemos encontrado una concentración mayor, tanto de tPA como de PAI-1, en ayunas en el grupo HE, en relación con el grupo HB. El tPA también mostró una concentración mayor en el posprandio en el grupo HE.Conclusión. Nuestros datos indican una activación mayor de la coagulación en varones jóvenes con un índice HOMA mayor a la mediana poblacional, independientemente de la composición de la dieta seguida (AU)

Background. Haemostasis is a complex process that regulates the integrity of the circulatory system. It has been shown that diet can modulate the concentration of some haemostatic markers, but it is not clear if there is regulation of haemostasis depending on insulin sensitivity. We investigated whether insulin sensitivity influences fasting and postprandial concentration of haemostatic markers (FVIIc, PAI-1, tPA). Methods. Twenty healthy young men were submitted to three dietary intervention periods (rich in monounsaturated, saturated or n3 fatty acids) for four weeks each. The participants were separated into two groups (High-HOMA or Low-HOMA) depending on the median for the HOMA score after each period. Fasting and postprandial samples were drawn for the determination of the haemostatic markers. Results. High-HOMA group showed higher tPA and PAI-1 concentration levels in the fasting state compared with Low-HOMA group (p < 9.05). The tPA mean was also higher in the postprandial determination in the High-HOMA group. The type of diet received did not affect these results.Conclusion. In our study, the participants with higher HOMA score had a higher fasting concentration of tPA and PAI-1, and a higher postprandial concentration of tPA compared with the Low-HOMA group. These data suggest a higher activation of the coagulation cascade in healthy people with a HOMA score greater than the median for each population (AU)

Melatonin administration increased plasminogen activator activity in ram spermatozoa.

The aim of the present study was to investigate the effect of melatonin on plasminogen activator activity (PAA), plasminogen activator inhibition (PAI) and plasmin inhibition (PI) in ram spermatozoa and seminal plasma, in correlation with changes in blood testosterone. Melatonin implants (18 mg) were placed subcutaneously in sixteen Chios rams in autumn and spring. Semen samples for spectrophotometrical assays were collected 36 h before the implantation of melatonin and thereafter once a week, for 17 weeks. Blood samples for testosterone assay (RIA) were collected 8h before implantation (one sample/30 min x 7.5 h) and thereafter every 15 days for 105 days after implantation. For each ram, six parameters of testosterone were estimated: mean value, basal level, number of peaks, peak amplitude, peak duration and mean testosterone concentration during peaks. Melatonin implantation during autumn induced an increase in PAA and t-PAI in spermatozoa; melatonin implantation in spring induced an additional increase in u-PAI and PI; no change in PAA, PAI or PI was found in seminal plasma, during autumn or spring. The melatonin-induced increase of PAA, PAI and PI in spermatozoa was in positive correlation with the increase of testosterone mean value, basal level and number of peaks; the increase of testosterone parameters was greater in autumn compared to spring. Changes of PAA, PAI and PI of spermatozoa, under the influence of melatonin, might indicate changes in the fertilizing ability of spermatozoa, since plasminogen activators and their inhibitors are present on the plasma and the outer acrosomal membrane of spermatozoa and are released during the acrosome reaction.

Expression and localisation of extracellular matrix degrading proteases and their inhibitors during the oestrous cycle and after induced luteolysis in the bovine corpus luteum.

The corpus luteum (CL) offers the opportunity to study high proliferative processes during its development and degradation processes during its regression. We examined the mRNA expression of matrix metalloproteases (MMP)-1, MMP-2, MMP-9, MMP-14, MMP-19, tissue inhibitor of MMP (TIMP)-1, TIMP-2, tissue plasminogen activator (tPA), urokinase plasminogen activator (uPA), uPA-receptor (uPAR), PA-inhibitors (PAI)-1, PAI-2 in follicles 20 h after GnRH application, CLs during days 1-2, 3-4, 5-7 and 8-12 of the oestrous cycle as well as after induced luteolysis. Cows in the mid-luteal phase were injected with Cloprostenol and the CLs were collected at 0.5, 2, 4, 12, 24, 48 and 64 h after PGF2alpha injection. Real-time RT-PCR determined mRNA expressions. Expression from 20 h after GnRH to day 12: MMP-1, MMP-2, MMP-14 and tPA showed a clear expression, but no regulation. TIMP-1 and uPAR mRNA increased when compared with the follicular phase. TIMP-2, MMP-9, MMP-19 and uPA increased from the follicular phase to days 8-12. PAI-1 and PAI-2 expression increased from days 1-7 and decreased to days 8-12. Induced luteolysis: MMP-1, MMP-2, MMP-9, MMP-14, MMP-19 and TIMP-1 all increased at different time points and intensities, whereas TIMP-2 was constantly decreased from 24 to 64 h. The plasminogen activator system and their inhibitors were up-regulated from 2 to 64 h, tPA was already increased after 0.5 h. Immunohistochemistry for MMP-1, MMP-2, MMP-14: an increased staining for MMP-1 and MMP-14 was seen in large luteal cells beginning 24 h after PGF2alpha application. MMP-2 showed a strong increase in staining in endothelial cells at 48 h.

Plasminogen activator system in oral squamous cell carcinoma.

BACKGROUND: The plasminogen activator system consists of two plasminogen activators, urokinase (uPA) and tissue (tPA); PA inhibitors (PAI-1, and -2), and a cell surface receptor for uPA (uPAR). The plasminogen activator system is involved at many stages of the metastatic cascade, including matrix remodelling, cell proliferation, and migration. AIMS: To compare tissue concentrations of the components of the plasminogen activator system in paired tumour tissue and normal tissue in patients with oral squamous cell carcinoma, and to correlate these with the histopathological grading of the tumour. METHODS: Thirty-eight paired tissue samples were analysed by enzyme-linked immunosorbent assays (ELISA; ng/mg protein) for uPA, tPA, uPAR, PAI-1, and PAI-2. RESULTS: Concentrations of uPA, uPAR, PAI-1, and PAI-2 were significantly higher in tumour than in normal oral tissue (median in uPAR tumour 1.6 (range; 0.1-7.5) ng/mg protein; normal=0.2 (0-2.3), p<0.05). There were strong correlations between the concentrations of certain components of the plasminogen activator system in particular between uPA, uPAR, and PAI-1 (p<0.05). Tissue concentrations of some components of the plasminogen activator system correlated with clinical and pathological indexes of aggression of tumours, including differentiation and T-stage. CONCLUSION: The relation between components of the plasminogen activator system, in particular uPA, uPAR, and PAI-1 in invasion, metastasis, prognosis, and survival, requires further investigation in oral squamous cell carcinomas.

Plasminogen activators and their inhibitors in human saliva and salivary gland tissue.

The purpose of this study was to identify plasminogen activators (PA) and their specific inhibitors in human cell-free saliva and to investigate their expression in salivary gland tissue. Saliva samples were obtained from 34 patients visiting a neurological out-patient department. The activities of tissue and urokinase plasminogen activators (tPA and uPA, respectively), the relative inhibition of tPA, and the amounts of plasminogen activator inhibitors 1 and 2 (PAI-1 and PAI-2, respectively) in cell-free saliva were studied. The activities of tPA and uPA, and tPA inhibition, were measured using in-house microtiter plate assays, and PAI-1 and PAI-2 levels were measured using commercial enzyme-linked immunosorbent assay (ELISA) kits. Immunohistochemistry was used to evaluate the expression of PAs and PAIs in the salivary gland. Tissue plasminogen activator activity was found in most samples, with a mean activity of 0.63 IU ml(-1). uPA was observed in only a few samples. PAI-1 was not detected, but PAI-2 was present in all samples (with a mean value of 11.1 ng ml(-1)). The mean PAI-2 level in women was 12.4 and in men was 7.6 ng ml(-1). The activity of tPA and the relative inhibition of tPA seemed to be inversely associated. Tissue plasminogen activator, PAI-1, and PAI-2 were evident in salivary gland tissue, whereas the expression of uPA was low. The tPA activity in saliva suggests an active proteolysis. Plasminogen activator inhibitor 2 was found to be the main inhibitor of PAs in saliva.

Plasminogen activators and their inhibitor gene expression in cutaneous NF1-related neurofibromas.

Cutaneous neurofibromatosis 1 (NF1)-related neurofibromas are benign tumors and composed of Schwann cells, perineurial cells and/or fibroblasts, endothelial cells, mast cells and macrophages. Extracellular proteolysis namely plasminogen activation (PA) operates in many tissue destructive processes. We wanted to study plasminogen activators, urokinase (uPA) and tissue type (tPA) and their inhibitor PAI-1, which have not earlier been studied comprehensively in cutaneous NF1-related tumors. We analyzed the distribution of uPA, tPA and PAI-1 antigen level by immunohistochemistry and mRNA level by in situ hybridization, to identify which cells are primarily involved in proteolytic activity and plasminogen activation. Twelve NF1 skin tumor samples from six patients were obtained during the operations. Mast cells, macrophages and endothelial cells were distributed only locally. Their expression levels of PA components were not so notable. Large extent of tumor cells of Schwann cell origin and prominent expression levels of uPA, tPA and PAI-1 indicated that these cells are responsible for the main source of PA components in cutaneous NF1-related neurofibromas.

Molecular biology of breast cancer

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Although Breast Cancer (BC) has been considered formany years as a single entity with a common managementand treatment, it is actually a extremely heterogeneousdisease which includes at least 4 or 5very different subtypes. The first step in the recognitionof the heterogeneity of BC was the demonstrationof the presence of functional hormonal receptors(HR) in nearly two thirds of breast cancer specimens.This finding, which established a first classification ofBC in two clear subtypes (HR-positive and HR-negative)was followed by the demonstration of many otherdifferential features. The her2/neu gene alteration,present in nearly 20% of BC tumors, is probably themost relevant of them, but certainly not the only one.The development of new technologies and, in particular,the use of complementary DNA (cDNA) microarrayswill allow us now the simultaneous analysisof thousands of genes and the establishment ofnew, more refined BC subtypes based on gene expressionprofiles/genetic fingerprints.This review discusses the practical applications ofmolecular analysis of BC, which can be classified infour categories:1. Establishment of a new molecular taxonomy ofbreast cancer.2. Definition of prognostic factors/prognostic indexesbased on molecular/genetic peculiarities.3. Prediction of response to diverse antitumoral treatments.4. Identification of molecular targets that allows thedevelopment of new tailored antitumor treatments

Mulberry anthocyanins, cyanidin 3-rutinoside and cyanidin 3-glucoside, exhibited an inhibitory effect on the migration and invasion of a human lung cancer cell line.

Anthocyanins, present in various fruits and vegetables as natural colorant, have been well characterized to be involved in various bioactive properties and are wildly used for their antioxidant properties. Furthermore, recent studies have revealed pleiotropic anticancer and antiproliferative capabilities of anthocyanin. Berry extract contains high amounts of anthocyanins and is commonly used in diet or in some therapeutic applications. In this study, we first observed that cyanidin 3-rutinoside and cyanidin 3-glucoside (extracted from Morus alba L.) exerted a dose-dependent inhibitory effect on the migration and invasion, of highly metastatic A549 human lung carcinoma cells in absence of cytotoxicity. The results showed that cyanidin 3-glucoside and cyanidin 3-rutinoside treatments could decrease the expressions of matrix matalloprotinase-2 (MMP-2) and urokinase-plasminogen activator (u-PA) in a dose-dependent manner and enhance the expression of tissue inhibitor of matrix matalloprotinase-2 (TIMP-2) and plasminogen activator inhibitor (PAI). Further analysis with semi-quantitative RT-PCR showed that these alterations were all on the transcriptional level. Further, a treatment of cyanidin 3-rutinoside and cyanidin 3-glucoside also resulted in an inhibition on the activation of c-Jun and NF-kappaB. Together, these result suggested that anthocyanins could decrease the in vitro invasiveness of cancer cells and therefore, may be of great value in developing a potential cancer therapy.

Plasminogen activator system in smokers and non-smokers with and without periodontal disease.

BACKGROUND: The present study assessed levels of plasminogen activator (PA) system proteins in gingival crevicular fluid (GCF) and serum of chronic gingivitis, chronic periodontitis patients and periodontally healthy subjects and evaluated how smoking influenced these levels. METHODS: Twenty chronic gingivitis; 20 chronic periodontitis patients and 20 periodontally healthy volunteers were consecutively recruited according to the inclusion criteria so that exactly half of the subjects in each category were smokers. GCF samples from four sites together with serum samples were obtained from each subject. GCF levels of tissue type PA (t-PA), urokinase type PA (u-PA), PA inhibitor-1 (PAI-1) and PA inhibitor-2 (PAI-2) and serum concentrations of cotinine, u-PA and PAI-1 were analysed by enzyme-linked immunosorbent assay. RESULTS: The only statistically significant difference between smokers and non-smokers was a lower GCF PAI-2 concentrations in healthy smokers compared with healthy non-smokers (p<0.01). Gingivitis and periodontitis patients had higher GCF concentrations of PAI-2 than healthy subjects (p<0.002 and p<0.02 respectively). The ratio of u-PA:PAI-1 and t-PA:PAI-1 were significantly higher in GCF of smokers with periodontitis compared with "healthy" smokers, whereas the ratio of t-PA:PAI-2 was significantly lower in smokers with periodontal disease (p<0.05). CONCLUSIONS: GCF levels of the PA system proteins are increased in chronic gingivitis and periodontitis compared with healthy gingiva. Smoking had only subtle effects on the GCF PA system proteins with the exception of PAI-2, and the balance of activators and inhibitors. These findings suggest one mechanism whereby smoking may exert detrimental effects on the periodontal tissues.

Plasminogen activators and plasminogen activator inhibitors in gingival crevicular fluid of cyclosporin A-treated patients.

BACKGROUND: The plasminogen activator (PA) system plays many roles in the inflammatory process and tissue remodelling and repair and is considered to play a significant role in periodontal tissue destruction and healing. The aim of this study was to evaluate the role of the PA system in cyclosporin A (CsA)-induced gingival overgrowth in renal transplant patients. METHODS: Eighteen renal transplant patients exhibiting moderate to severe CsA-induced gingival overgrowth, 10 other renal transplant patients receiving CsA therapy but showing no sign of CsA-induced gingival overgrowth (CsA-H), 16 chronic gingivitis patients (CG) and 16 systemically and periodontally healthy control subjects (H) were included in the study. Gingival crevicular fluid (GCF) samples were obtained from four randomly selected sites in each subject with the exception of the CsA-induced gingival overgrowth group, where four GCF samples were harvested from sites with severe overgrowth (CsA GO+) and from four sites without any gingival overgrowth (CsA GO-). The GCF levels of albumin, tissue-type plasminogen activator (t-PA), urokinase-type plasminogen activator (u-PA), plasminogen activator inhibitor 1 (PAI-1) and plasminogen activator inhibitor 2 (PAI-2) were analysed by enzyme-linked immunosorbent assay. The results were tested for statistical differences. RESULTS: In CsA GO+ sites t-PA levels were significantly elevated in comparison with gingivitis and healthy sites, while PAI-2 levels in these sites showed statistically significant differences only with CsA-H and gingivitis sites (p<0.05). The levels of t-PA and PAI-2 were significantly higher in CsA GO- sites compared with those of CsA-H, gingivitis and healthy sites (p<0.05). The levels of u-PA and PAI-1 failed to show significant differences between the study groups. CONCLUSIONS: The findings of the present study indicate alterations in GCF t-PA and PAI-2 levels in CsA-induced gingival overgrowth and might suggest involvement of the plasminogen activating system in the pathogenesis of this side-effect of CsA therapy. However, to what extent these molecules contribute to the pathogenesis of CsA-induced gingival overgrowth remains to be determined.

Blood coagulation and fibrinolysis of rats fed fish oil: reduced coagulation factors especially involved in intrinsic pathway and increased activity of plasminogen activator inhibitor.

Differences in the coagulation and fibrinolytic system of rats fed a fish oil based diet (fish oil diet) and fed a soybean oil based diet (control diet) were determined. Concentrations of plasma lipids were depressed in rats fed the fish oil diet. Prothrombin time (PT) and activated partial thromboplastin time (APTT) of rats fed the fish oil diet were longer than for the rats fed the control diet. Fish oil intake lowered the activities of most of the blood coagulation factors, and strongly depressed the factors involved in the intrinsic pathway. Fish oil also affected the fibrinolysis of rats. Plasminogen activator inhibitor (PAI) activity was elevated in rats fed the fish oil diet. In this study, both blood coagulation and fibrinolysis were down-regulated by feeding the fish oil diet.

Occurrence of components of fibrinolytic pathways in situ in laryngeal cancer.

Malignancy is characterized by the occurrence of components of coagulation reaction pathways in situ within tumor tissues detectable immunohistochemically. However, tumors vary in the details of this coagulation-cancer interaction. We have previously described tumor cell-associated tissue factor (TF), factor (F) VII, and F X in laryngeal carcinoma tissues. Fibrinogen and F XIIIa were found in the tumor connective tissue. Tissue factor pathway inhibitor (TFPI) occurred in the tumor connective tissue and on microvascular endothelial cells and normal squamous epithelial cells but not in the tumor cells. Fibrin (thrombin-cleaved fibrinogen) existed at the host-tumor interface and the margins of tumor nodules consistent with an active tumor cell-associated clotting pathway in this tumor type. Studies were extended here to detect components of fibrinolytic pathways. Plasminogen and tissue plasminogen activator (t-PA) were detected on laryngeal tumor cells, particularly in more well-differentiated cases. Low-molecular-weight urokinase plasminogen activator (LMW u-PA) was primarily a feature of more undifferentiated laryngeal carcinoma cells. Staining to a lesser extent was found for high-molecular-weight u-PA (HMW u-PA) on tumor cells and various normal cell types in the tumor tissue. Relatively weak and variable tumor cell staining was found for plasminogen activator inhibitors (PAI) 1, 2, and 3. Trace staining was found for u-PA receptor (u-PAR) in differentiated tumor cells. The significance of coagulation and fibrinolytic pathways present in situ to the economy of laryngeal carcinoma remains to be determined.

Plasminogen activator activity in cortical granules of bovine oocytes during in vitro maturation.

In this study, we provide evidence that plasminogen activator of tissue-type (t-PA), at least, is present in extracts of bovine oocyte cortical granules, and that its activity varies significantly with the duration of oocyte in vitro maturation. Cortical granules were collected from bovine oocytes by means of micromanipulation, after 0, 12, or 24 h of IVM. Our results show that plasminogen activator activity of cortical granule extracts was significantly higher after 24 h of IVM than after 12 h of IVM or before IVM. This activity was apparently due, at least partly, to tissue-type plasminogen activator as shown immunologically. No evidence was found for the presence of urokinase-type plasminogen activator, plasminogen activator inhibitors or plasmin inhibitors in bovine oocyte cortical granule extracts. Our findings further support the hypothesis that t-PA activity of oocyte origin may have a role in oocyte maturation or fertilization, as well as in post-fertilization events, such as cortical reaction and formation of the zona block to polyspermy.

Biochemical markers in breast cancer: which ones are clinically useful?

Breast cancer is the most common neoplasm affecting women in the Western world with approximately 1 in 11 developing the malignancy and 1 in 30 dying from the disease. For optimum management of these patients, assay of certain biochemical markers is necessary. Clinically, the most useful markers in breast cancer are the estrogen and progesterone receptors that are used to predict response to hormone therapy. Both American and European Expert Panels have recommended routine determination of these steroid hormone receptors in all patients with breast cancer. For surveillance of patients with diagnosed breast cancer, both CA 15-3 and BR 27.29 can be used. Serial determinations of these markers have the potential to preclinically detect recurrent disease and monitor the treatment of advanced disease. However, the benefit of this monitoring on patient outcome or quality of life is not clear. New or potentially new markers for breast cancer include BRCA1 and BRCA2 for selecting patients at high risk of developing breast cancer, urokinase plasminogen activator and PA1-1 for assessing prognosis and HER-2 for predicting response to the therapeutic antibody, Herceptin.