Bleeding Rate After Tooth Extraction in Patients Under Oral Anticoagulant Therapy.

OBJECTIVES: The aim of this single-cohort prospective study was to evaluate the risk of adverse outcomes after tooth extraction in patients suffering from cardiovascular disorders and under oral anticoagulant therapy with an international normalized ratio within the value of 3.0. METHODS: Two hundred ninety-three patients (mean age of 58.7 years) were enrolled and 560 tooth extractions were performed. Fresh extraction sockets were treated with collagen tablets and sutures. The risk of increased bleeding rate was evaluated for type of drug therapy (acenocoumarol or warfarin), type of cardiovascular diseases, and number of tooth extractions. Level of significance was set at 0.05. RESULTS: The overall bleeding event rate was 6.8%. Among patients who had bleeding events, 4 suffered from valvular disorders, whereas 11 suffered from arrhythmias (8) or cardiomyopathies (3). The remaining 5 patients had a history of cardiomyopathy and arrhythmia.The bleeding events in patients who had more than 2 tooth extractions were significantly higher than those observed in patients who had only 1 tooth extraction (P <0.05). CONCLUSION: Patients who received more than 2 tooth extractions, who were under treatment with acenocoumarol, and who suffered from multiple cardiovascular diseases were at high risk for bleeding events.

Immunohistochemical assessment of mitochondrial superoxide dismutase (MnSOD) in colorectal premalignant and malignant lesions.

INTRODUCTION: It is generally accepted that mitochondria are a primary source of intracellular reactive oxygen species (ROS). Under physiological circumstances they are permanently formed as by-products of aerobic metabolism in the mitochondria. To counter the harmful effect of ROS, cells possess an antioxidant defence system to detoxify ROS and avert them from accumulation at high concentrations. Mitochondria-located manganese superoxide dismutase (MnSOD, SOD2) successfully converts superoxide to the less reactive hydrogen peroxide (H2O2). To the best of our knowledge, there are no available data regarding immunohistochemical expression of MnSOD in colorectal neoplastic tissues. AIM: To investigate the immunohistochemical expression status of MnSOD in colorectal premalignant and malignant lesions. MATERIAL AND METHODS: This study was performed on resected specimens obtained from 126 patients who had undergone surgical resection for primary sporadic colorectal cancer, and from 114 patients who had undergone colonoscopy at the Municipal Hospital in Jaworzno (Poland). Paraffin-embedded, 4-µm-thick tissue sections were stained for rabbit polyclonal anti SOD2 antibody obtained from GeneTex (clone TF9-10-H10 from America Diagnostica). RESULTS: Results of our study demonstrated that the development of colorectal cancer is connected with increased expression of MnSOD both in adenoma and adenocarcinoma stages. Samples of adenocarcinoma with G2 and G3 grade showed significantly higher levels of immunohistochemical expression of this antioxidant enzyme. Moreover, patients with the presence of lymphovascular invasion and higher degree of regional lymph node status have been also characterised by higher levels of MnSOD expression. The samples of adenoma have been characterised by higher levels of MnSOD expression in comparison to normal mucosa as well. Interestingly, there was no significant correlation between expression and histological type of adenoma. CONCLUSIONS: Development of colorectal cancer is connected with increased expression of MnSOD both in adenoma and adenocarcinoma stages.

Tissue factor is unregulated in microvascular endothelial cells of patients with heart failure.

AIMS: Several lines of evidence point to hypercoagulability as an important factor for heart failure (HF) pathogenesis. METHODS: We hypothesised that endothelial tissue factor (TF) expression reflects altered tissue haemostasis which is related to the severity of HF. Accordingly, we investigated TF expression in the biopsies of 60 patients with HF and 22 without HF. In addition, we assessed the relationship between endothelial TF expression and clinical markers of HF severity. RESULTS: The control subjects without HF presented absent or weak TF expression in few microvessels, while the endomyocardial biopsies of patients with HF, capillary vessels presented both weak and severe staining patterns by immunohistochemistry usually with regional distribution. This was collaborated by the immune electron microscopic study. The severe microvessel TF antigen expression was found in 11 (18.3%) patients with HF. The endothelial TF expression was inversely associated with left ventricular ejection fraction (r=-0.42, p=0.001) and positively with N-terminal brain natriuretic peptide (r=0.36, p<0.023), markers of HF severity. CONCLUSIONS: Regional upregulation of the TF in the capillary endothelial cells suggests local myocardial thrombogenicity. Furthermore, the relationship between endothelial TF and HF severity would be keeping in line with the hypothesis that an altered tissue haemostasis is most profoundly expressed in patients with severe HF. Weak TF expression found in several microvessels of the biopsy specimens patients without HF pathology might be potentially related to a low basal level of activation of the clotting system in normal individuals.

Response to Dual Antiplatelet Therapy Does Not Impact Bleeding Risks in Patients Undergoing Oral Surgery after Acute Coronary Syndromes.

INTRODUCTION: Oral surgery (OS) in patients on antecedent dual antiplatelet therapy (DAPT) may be associated with extra bleeding risks. Monitoring platelet activity in such patients may be beneficial for safety when performing OS. OBJECTIVES: The aim of this study was to assess whether platelet function during DAPT impacted the risk of bleeding following OS in patients with acute coronary syndromes (ACS). PATIENTS AND METHODS: Patients who required OS on top of DAPT with aspirin and clopidogrel (n = 55) for invasively treated ACS were included. The control group (n = 33) consisted of patients who underwent OS with no antiplatelet agent. Platelet aggregation before OS was assessed with a Multiplate® analyzer. Bleeding during OS and at days 1, 3, 7 and 10 after surgery was serially evaluated. RESULTS: All 88 patients completed the study. An incomplete response to aspirin or clopidogrel was observed in 43.6% of the patients. In 11% of the cases, an excessive response to clopidogrel was demonstrated. No excessive bleeding upon OS was exhibited in either group during the entire follow-up. Platelet aggregation values and the use of DAPT did not impact the performance of OS. CONCLUSION: Therapy with clopidogrel and aspirin after ACS does not seem to increase the risk of real-life bleeding following OS, regardless of the platelet activity response to DAPT. © 2015 S. Karger AG, Basel.

Angiogenesis in primary hyperparathyroidism.

Angiogenesis can be described as a formation of new vessels from the existing microvasculature and is a process of great importance to the tumor development. Parathyroid tissue can trigger spontaneous induction of angiogenesis in vitro and in vivo models in a vascular endothelial growth factor (VEGF)-dependent manner. Autotransplantated parathyroid tissue after thyroidectomy is able to form new vasculature and produce parathormone, maintaining calcium homeostasis. A great amount of factors contributes to the process of new vessel formation in primary hyperparathyroidism, such as VEGF, transforming growth factor ß, and angiopoietins. Studies demonstrated that markers for angiogenesis can be useful in distinguishing between parathyroid hyperplasia and neoplasia, due to the increased angiogenesis in parathyroid proliferative lesions compared with parathyroid adenomas. These factors include, inter alia, VEGF, VEGFR2, CD105, and fibroblast growth factor-2. Although these differences appear promising in the differential diagnosis, there is an overlap between benign and malignant parathyroid lesions and there is no definite cutoff value. Loss of heterozygosity and comparative genomic hybridization studies revealed chromosomal regions frequently altered in parathyroid tumorigenesis at 9p21, 1p21-22, 1p35-36, and 11q13. Therefore, immunohistochemistry and genetic testing should be an additional diagnostic marker in combination with the traditional criteria. A better understanding of angiogenesis in primary hyperparathyroidism could result in more precise assessment of diagnosis and more effective treatment, especially in those cases, in which the commonly used parameters are insufficient.

Tissue factor and tissue factor pathway inhibitor in chronically inflamed gallbladder mucosa.

We characterised a tissue factor (TF) and tissue factor pathway inhibitor (TFPI) expression in relation to severity of inflammatory infiltration of the gallbladder mucosa in a chronic cholecystitis. We prospectively studied the gallbladder specimens obtained from 54 patients who had undergone cholecystectomy due to chronic calculous cholecystitis and 16 calculosis-free gallbladder specimens obtained from patients who underwent cholecystectomy due to the polyp/polyps as well as in cases of gallbladder injury. To assess TF and TFPI immunoreactivity by immunohistochemistry, the monoclonal anti-human TF and TFPI antibodies were used. The inflammatory infiltration of the gallbladder mucosa was reflected by the number of CD3 and CD68 positive cells. The expression of TF and TFPI differed significantly between the cholecystitis and the control group. Most capillary endothelial cells of the cholecystitis group presented weak expression for TFPI. The mean number of CD3 positive lymphocytes in the cholecystitis group was 18.6 ± 12.2, but the mean number of CD68 positive cells was 29.7 ± 13.9. In the control sections, it was 3.1 ± 1.9 and 8.8 ± 3.9, respectively (P < 0.001). The results of the current study suggest that the tissue procoagulant state found may be engaged in the etiopathogenesis of the cholecystitis.

Role of Notch signaling pathway in gastric cancer pathogenesis.

Notch signaling pathway is activated dynamically during evolution playing significant role in cell fate determination and differentiation. It has been known that alterations of this pathway may lead to human malignancies, including gastric cancer. Despite a decline in the overall incidence, this disease still remains an important global health problem. Therefore, a better understanding of the molecular alterations underlying gastric cancer may contribute to the development of rationally designed molecular targeted therapies. It has been reported that Notch1 receptor could become a prognostic marker of gastric cancer and novel target for gastric cancer therapy. Among the novel and targeted approaches for the treatment of gastric cancer is also the process of Notch receptors regulation by specific microRNA. γ-secretase inhibitors are also taken into consideration.

The Notch ligand Delta-like 4 (DLL4) as a target in angiogenesis-based cancer therapy?

Angiogenesis is a complex multistep process by which new capillary structures arise from pre-existing vessels in response to angiogenic stimuli. This process plays a key role during tumorigenesis because the vascular network within the tumor enables malignant cells to establish distant metastases. Thus, it is not surprising that targeting tumors with angiogenesis-based therapy remains a significant area of preclinical and clinical studies. One of the most prominent factors considered as a promising target in such therapy is the Notch ligand Delta-like 4 (DLL4). Emerging evidence suggests that blockade of DLL4 in tumors results in excessive but non-productive angiogenesis which affects tumor growth, even in tumors which are insensitive to anti-VEGF therapy. Nevertheless, the careful evaluation of adverse effects on normal organs' physiology in relation to therapeutic doses of DLL4 inhibitors will be critical for advancement of DLL4 blocking agents in clinical practice.

Tissue hemostasis and chronic inflammation in colon biopsies of patients with inflammatory bowel disease.

Inflammatory bowel disease (IBD) is characterized by a chronic inflammation accompanied by procoagulation settings. However, tissue hemostasis in IBD patients was only incidentally reported. Accordingly, the current study characterizes changes in tissue hemostasis components in a colon inflammatory setting. Serial cryostat sections of endoscopic mucosal biopsy specimens taken from 26 consecutive IBD patients diagnosed de novo and normal colon resection specimens taken from 6 patients were immunohistochemically stained with monoclonal anti-human tissue factor (TF), tissue factor pathway inhibitor (TFPI), thrombomodulin (TM), as well as CD3 and CD68 positive cells. The hemostatic components studied differed significantly from the control subjects. Up-regulation predominated in the case of TF while down-regulation was mainly found in TM and TFPI in IBD. In the control sections, TF was observed in a few fibroblast-shaped cells in the lamina propria, while in the majority of IBD sections, TF positively stained small microvessels, infiltrating mononuclear cells and fibroblast-shaped cells tightly surrounding the colon crypts. Thrombomodulin intensively stained the endothelium of the small capillary vessels in the control, whereas such staining mainly accompanied infiltrating mononuclear cells of the IBD subjects. Tissue factor pathway inhibitor positively stained the endothelium of the small capillary vessels in the control group, whereas in the IBD group endothelial cells presented only weak TFPI staining. The mean number of CD3-positive lymphocytes in IBD was 23.3 ± 14.3, but the mean number of CD68-positive cells was 114.5 ± 55.8. In the control sections, it was 4.1 ± 2.4 and 39.6 ± 17.9, respectively. There was no relationship between CD3 and CD68 (+) cells and the hemostasis markers studied. The results of the current study indicate a shift of tissue hemostasis toward the procoagulant state irrespective of the severity of inflammatory infiltration. In addition, TF distribution in the colon sections of IBD patients may indicate a role in the restoration of the barrier function in injured intestinal mucosa.

Protective effect of intermittent clamping of the portal triad in the rat liver on liver ischemia-reperfusion injury.

BACKGROUND: Intermittent clamping (IC) of the portal triad is an effective method of protecting the liver from ischemia-reperfusion injury (IR). In clinical practice, this method is employed during a resection, but its mechanism is still not clear. OBJECTIVES: To evaluate the effect of IC on rat liver and determine its mechanisms. MATERIALS AND METHODS: Wistar rats were submitted to 60-min IC (cycles of 12-min clamping followed by 4-min reperfusion), and the samples were collected after 1, 6, and 72 hrs of reperfusion. We determined the serum activity of alanine aminotransferase (ALT), and measured the concentration of TNF-α, malondialdehyde (MDA) and myeloperoxidase (MPO) in liver homogenates. The apoptosis of hepatocytes was evaluated immunohistochemically. RESULTS: When compared to the IR rats, the activity of ALT decreased in the IC group in all periods of observation (the highest decrease of ~48% after 1 hr of reperfusion). When compared to the IR group, a statistically significant decrease (p < 0.05) in the TNF-α concentration (~33%) in the IC rats occurred only after 1 hr of reperfusion, and it was accompanied by a decrease in the MPO concentration after 1 and 6 hrs of reperfusion. IC reduces the effects of reactive oxygen species (ROS) activity, which has been confirmed by a statistically significant decrease in MDA concentration by 25%-35% in all studied periods. The limitation of hepatocytes apoptosis due to IC occurs in the early (~26%; p < 0.05) and late (~45%; p < 0.01) phases of reperfusion. CONCLUSIONS: The use of IC in early phase of reperfusion brings about a decrease in TNF-α release, which can be related to liver injury due to neutrophil infiltration and apoptotic cell reduction. It seems that the reduction of lipid peroxidation may also limit the liver injury.

The dietary flavonol fisetin enhances the apoptosis-inducing potential of TRAIL in prostate cancer cells.

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is an endogenous agent that induces apoptosis selectively in cancer cells. Soluble or expressed in immune cells, TRAIL plays an important role in the defense against tumour cells. The resistance of cancer cells to TRAIL immune surveillance is implicated in tumour development. Naturally occurring flavonoids can sensitize TRAIL-resistant cancer cells and augment their apoptotic activity. Fisetin, a dietary flavonol has cancer preventive properties. This study was designed to investigate the effect of fisetin on the TRAIL-induced apoptosis potential in prostate cancer cells. Prostate cancer cell lines represent an ideal model for research in chemoprevention. Cytotoxicity was measured by MTT and LDH assays. Apoptosis was detected using Αnnexin V-FITC by flow cytometry and fluorescence microscopy. Mito-chondrial membrane potential (ΔΨm) was evaluated using DePsipher staining by fluorescence microscopy. Death receptor (TRAIL-R1 and TRAIL-R2) expression was analysed by flow cytometry. Inhibition of NF-κB (p65) activation was confirmed with an ELISA-based TransAM NF-κB kit. Caspase-8 and caspase-3 activities were determined by colorimetric protease assays. Our study demonstrates that fisetin sensitizes the TRAIL-resistant androgen-dependent LNCaP and the androgen-independent DU145 and PC3 prostate cancer cells to TRAIL-induced death. Fisetin augmented TRAIL-mediated cytotoxicity and apoptosis in prostate cancer LNCaP cells by engaging the extrinsic (receptor-mediated) and intrinsic (mitochondrial) apoptotic pathways. Fisetin increased the expression of TRAIL-R1 and decreased the activity of NF-κB. Co-treatment of cancer cells with TRAIL and fisetin caused significant activation of caspase-8 and caspase-3 and disruption of ΔΨm. Our data indicate the usefulness of fisetin in prostate cancer chemoprevention through enhancement of TRAIL-mediated apoptosis.

Therapeutic window for calcium-channel blockers in the management of dilated cardiomyopathy: a prospective, two-centre study on non-advanced disease.

OBJECTIVE: This study aimed to investigate the usefulness of the calcium-channel blocker verapamil in non-advanced dilated cardiomyopathy (DCM). METHODS: This was a randomised trial of 70 DCM patients treated with carvedilol (36 patients) and verapamil (instead of ß-blocker; 34 patients) for 12 months. The remaining heart failure (HF) therapy was constant in both groups. The primary outcomes were to determine selected echocardiography parameters and functional status of patients. The secondary outcome included death, heart transplantation and re-hospitalisation due to HF progression. RESULTS: Of the primary outcomes, only the mean ratio of early to late transmitral flow velocities increased significantly in the verapamil-treated patients as compared with the carvedilol-based therapy (1.1 ± 0.3 vs. 0.7 ± 0.2; 95% CI -0.6 to -0.1; p = 0.015). Simultaneously, the Minnesota Quality of Life improved significantly in the verapamil group (95% CI 5.2-19.9; p = 0.002). It was accompanied by the favourable effect of verapamil therapy on exercise capacity in the 6-min walk test (95% CI 21.3-110.7; p = 0.005). CONCLUSION: The addition of verapamil to angiotensin-converting enzyme and aldosterone inhibitors in non-advanced DCM patients has been shown to have a neutral or even positive effect in a few patients.

[Neutrophils' contribution to ischaemia and reperfusion injury in liver]. / Udzial neutrofili w uszkodzeniu watroby na skutek niedokrwienia i reperfuzji.

Neutrophils are cells which induce liver injury due to ischaemia and reperfusion. They are active especially in the later phase of reperfusion (> 6 hrs) since they gather in the liver and release mediators damaging hepatocytes directly. Inflow ofneutrophils into the liver is possible due to chemotaxia which involves, among others, chemokines CXC (interleukin-8 and its counterparts). Neutrophils' ability to induce chemotaxia is determined by their specific glycoprotein receptors in cell membranes. Neutrophils contribute to ischaemia/reperfusion liver injury because they adhere to vessel endothelium, cross the wall of hepatic microcirculation vessels and adhere to hepatocytes. Selectins play a crucial role in neutrophils' contact with endothelial cells, and ICAM-1, predominantly in their adhesion to hepatocytes. Also beta2-integrin and Mac-1 play essential role. Neutrophils damage hepatocytes by realising proteases, free radicals, TNF-alpha, TGF-beta and leucotrien. Neutrophils together with endothelial cells also disturb the hepatic microcirculation.

[Apoptosis and necrosis--two different ways leading to the same target]. / Apoptoza i martwica--dwie drogi do jednego celu.

Both apoptosis and necrosis lead to the same target, i.e. the death of the cell. However their mechanisms are different although they are evoked by similar factors. The differences between apoptosis and necrosis concern not only morphological features but also biochemical changes taking place in the cell. In the case of apoptotic death of cell, its intracellular content is not released and that is why inflammatory reaction, which is present in necrosis, is absent. In necrosis, defined as a passive death, majority of enzymes as well as metabolic tracts are lost and the released lysosome enzymes digest cellular components. Apoptosis, on the other hand, is an active process which requires supply of adenosine triphosphate (ATP) and which is controlled by many genes. There are many factors that determine the kind of cell death. The most important of them seems to be the level of intracellular ATP connected with caspase activation. This is the reason why mitochondria are considered to be the main cell organelles, which determine the type of cell death. Disturbances in the flow of ions connected with the activation of specific ion channels as well as free oxygen radicals are of importance here, too.

[Effect of ischemia and reperfusion on liver circulation changes]. / Wplyw niedokrwienia i reperfuzji na zmiany w krazeniu watrobowym.

Liver transplantation is becoming more and more common treatment method of liver diseases. The occurring complications may result from ischemia and reperfusion. However, the precise mechanism of these changes is not fully known. Microcirculation disturbances leading to ischemic damage of cells or their death are among those factors which cause liver damage under the influence of ischemia and reperfusion. These disturbances are intensified by increase of liver ischemia time and correlate with the number of wasted away hepatocytes. Endothelial cells, Browicz-Kupffer cells, neutrophils and thrombocytes are thought to play an essential role in liver microcirculation disturbances. Disturbed balance between local vasodilators and vasoconstrictors is also an important factor as it increases the lesions caused by reperfusion due to improper blood circulation. Nitrogen oxide (NO) is the most important local vasodilator. Inhibition of its synthesis in the period of early liver damage due to reperfusion causes a decrease of blood flow and increase of the occurring changes. Such strong vasoconstrictors as endothelin-1 and thromboxane play an important role. Reperfusion by damaging endothelial cells of sinusoid vessels affects the loss of endothelial barrier by the liver sinusoid vessels.

RNA and protein synthesis in different organs of rat offspring after chronic cadmium exposure during pregnancy.

Despite binding by placental metallothionein, cadmium (Cd) relatively easily enters fetal circulation and may be harmful to tissues and organs of offspring. Although Cd toxicology is relatively well described in the literature there are only few studies on Cd toxicity exerted during fetal life. We examined the influence of cadmium exposure during pregnancy on RNA and protein synthesis in different organs of the rat offspring. Their dams were fed diet containing cadmium chloride-treated drinking water during the whole pregnancy period at 50 ppm dose level. The offspring, 6-weeks-old male Wistars rats, weighing 105 + 10 g were subjected to examination. Synthesis of RNA and proteins was quantitated by scintillation technique, which measured incorporation of tritiated uridine and alanine, respectively. A set of 17 organs and tissues was examined. RNA synthesis increased significantly in buccal mucosa, tongue, parotid gland, cardiac muscle, brain and bone marrow. A strong induction of RNA synthesis in all four studied brain regions attracts special attention. The activation of RNA metabolism may be partly explained by the increased expression of genes involved in detoxication and adaptation (e.g., metallothionein, stress response proteins, etc.). A profile of protein synthesis was much more heterogenous with elevated H3-alanine uptake in 12 organs of experimental animals, however without any statistical significance. Since the study of protein synthesis did not demonstrate any significant changes in Cd-treated animals, the profile of RNA synthesis cannot be simply extrapolated on protein synthesis, probably because of complex post-transcriptional and post-translational genetic modifications.

[Ammonia and GABA-ergic neurotransmission in pathogenesis of hepatic encephalopathy]. / Amoniak i neurotransmisja GABA-ergiczna w patogenezie encefalopatii watrobowej.

Pathogenesis of hepatic encephalopathy has not been fully revealed and there are many factors which may affect its development. Ammonia and changes in GABA-ergic neurotransmission seem to be the most essential of these factors. Hepatic encephalopathy is frequently, though not always, accompanied by elevated blood ammonia level. Due to the changes in permeability of blood-brain barrier the ammonia level in the brain also increases which results in both stimulating and inhibitory neurotransmission disturbances. Ammonia also affects abnormal interaction of metabolic neurones and astrocytes as well as glutamine-serotonin balance. Another essential factor affecting hepatic encephalopathy development are disturbances in GABA-ergic neurotransmission connected with GABAA receptor complex. When the liver is damaged GABA-ergic neurotransmission increases due to a higher GABA level, natural benzodiazepine receptor agonists as well as neurosteroids synthesised in astrocytes. Many studies point to the fact that ammonia and GABA-ergic neurotransmission disturbances interrelate with each other. There is a concept saying that both these factors cause hepatic encephalopathy. Ammonia may indirectly increase GABA-ergic neurotransmission and also inhibit the function of the central nervous system by synergistic activity with benzodiazepine receptor ligands. So far it is not known whether GABA-ergic neurotransmission is affected by ammonia only or by other factors as well.

[Therapeutic management of hepatic encephalopathy]. / Postepowanie terapeutyczne w encefalopatii watrobowej.

Therapeutic management in hepatic encephalopathy depends on its etiology as well as progression degree. Both in acute and chronic encephalopathy one should tend to establish probable causes and try to eliminate them. Cutting down on proteins in diet is one of the most important suggestions in chronic hepatic encephalopathy. In order to reduce intestinal production of ammonia, non-absorbable disaccharides (lactulose), antibiotics (neomycin) and sodium benzoate are the most commonly used. Branched chain amino acids administered orally or parenterally may be useful in improving patient's condition and restoring the balance of blood amino acids. The GABA-benzodiazepine receptor theory led to application of its antagonists, such as flumazenil, in the management of hepatic encephalopathy. However, providing a proper treatment is not easy due to unstable and often not very characteristic course of hepatic encephalopathy. What is more, clinical trials of some drugs used in the treatment of hepatic encephalopathy do not confirm their effectiveness.