Contrast-enhanced ultrasound in the diagnosis of hepatocellular carcinoma.

Surveillance of patients at risk of developing hepatocellular carcinoma (HCC) is based on ultrasound (US) examinations performed at either 6 or 12 month intervals. Early detection of HCC in patients with cirrhosis is a challenging issue, since the different entities that are involved in the multi-step process of hepatocarcinogenesis – such as low-grade and high-grade dysplastic nodule – share common US features. Contrast-enhanced US allows reliable detection of arterial neoangiogenesis associated with a malignant transformation. Several reports have shown that the ability of contrast-enhanced US to diagnose HCC currently approaches that of optimized multidetector computed tomography (CT) or dynamic magnetic resonance (MR) imaging protocols. The use of contrast-enhanced US to characterize nodular lesions in cirrhosis has been recently recommended by the clinical practice guidelines issued by the European Federation of Societies for Ultrasound in Medicine and Biology and the American Association for the Study of Liver Diseases. However, contrast-enhanced US has not resulted in any significant improvement in the ability of US to detect small tumor foci, since a comprehensive assessment of the whole liver parenchyma cannot be accomplished during the short duration of the arterial phase. Hence, CT or MR imaging are still mandatory for proper intrahepatic staging of the disease

Serum Albumin Is Inversely Associated With Portal Vein Thrombosis in Cirrhosis

We analyzed whether serum albumin is independently associated with portal vein thrombosis (PVT) in liver cirrhosis (LC) and if a biologic plausibility exists. This study was divided into three parts. In part 1 (retrospective analysis), 753 consecutive patients with LC with ultrasound-detected PVT were retrospectively analyzed. In part 2, 112 patients with LC and 56 matched controls were entered in the cross-sectional study. In part 3, 5 patients with cirrhosis were entered in the in vivo study and 4 healthy subjects (HSs) were entered in the in vitro study to explore if albumin may affect platelet activation by modulating oxidative stress. In the 753 patients with LC, the prevalence of PVT was 16.7%; logistic analysis showed that only age (odds ratio [OR], 1.024; P = 0.012) and serum albumin (OR, -0.422; P = 0.0001) significantly predicted patients with PVT. Analyzing the 112 patients with LC and controls, soluble clusters of differentiation (CD)40-ligand (P = 0.0238), soluble Nox2-derived peptide (sNox2-dp; P < 0.0001), and urinary excretion of isoprostanes (P = 0.0078) were higher in patients with LC. In LC, albumin was correlated with sCD4OL (Spearman's rank correlation coefficient [r(s)], -0.33; P < 0.001), sNox2-dp (r(s), -0.57; P < 0.0001), and urinary excretion of isoprostanes (r(s), -0.48; P < 0.0001) levels. The in vivo study showed a progressive decrease in platelet aggregation, sNox2-dp, and urinary 8-iso prostaglandin F2 alpha-III formation 2 hours and 3 days after albumin infusion. Finally, platelet aggregation, sNox2-dp, and isoprostane formation significantly decreased in platelets from HSs incubated with scalar concentrations of albumin. Conclusion: Low serum albumin in LC is associated with PVT, suggesting that albumin could be a modulator of the hemostatic system through interference with mechanisms regulating platelet activation

Absence of Nitrergic Modulation of Starling Response in Haemoglobin-Less Antarctic Fish <i>Chionodraco hamatus</i>

The Frank-Starling response is an intrinsic heart property that is particularly evident in the fish heart because piscine cardiomyocytes are extremely sensitive to stretch. Several mechanisms and compounds influence the Frank-Starling response, including the free radical nitric oxide produced by nitric oxide synthases in the vascular endothelium and cardiomyocytes of all vertebrates. Besides its role in scavenging nitric oxide, hemoglobin may act as a source and transporter. In this context, the hemoglobin-less Antarctic teleost Chionodraco hamatus (icefish) represents a unique opportunity to investigate the involvement of nitric oxide in the Frank-Starling response. Using an isolated perfused heart preparation, weverified a basal nitrergic tone that is not implicated in the Frank-Starling response. In addition, by comparing nitric oxide synthases expression and activation in C. hamatus and the red-blooded Antarctic teleost Trematomus bernacchii, we found the endothelial isoform of nitric oxide synthase (the primary generator of nitric oxide during shear stress) to be less expressed and activated in the former

Antioxidant Responses Induced by PFAS Exposure in Freshwater Fish in the Veneto Region

In recent decades, the interest in PFAS has grown exponentially around the world, due to the toxic effects induced by these chemical compounds in humans, as well as in other animals and plants. However, current knowledge related to the antistress responses that organisms can express when exposed to these substances is still insufficient and, therefore, requires further investigation. The present study focuses on antioxidant responses in Squalius cephalus and Padogobius bonelli, exposed to significant levels of PFAS in an area of the Veneto Region subjected to a recent relevant pollution case. These two ubiquitous freshwater species were sampled in three rivers characterised by different concentrations of PFAS. Several biomarkers of oxidative stress were evaluated, and the results suggest that PFAS chronic exposure induces some physiological responses in the target species, at both cellular and tissue scales. The risk of oxidative stress seems to be kept under control by the antioxidant system by means of gene activation at the mitochondrial level. Moreover, the histological analysis suggests an interesting protective mechanism against damage to the protein component based on lipid vacuolisation

An Experimental Study on Antioxidant Enzyme Gene Expression in <i>Trematomus newnesi</i> (<i>Boulenger, 1902</i>) Experimentally Exposed to Perfluoro-Octanoic Acid

Antarctica is the continent with the lowest local human impact; however, it is susceptible to pollution from external sources. Emerging pollutants such as perfluoroalkyl substances pose an increasing threat to this environment and therefore require more in-depth investigations to understand their environmental fate and biological impacts. The present study focuses on expression analysis at the transcriptional level of genes coding for four antioxidant enzymes (sod1, sod2, gpx1, and gpx4) in the liver and kidney of an Antarctic fish species, Trematomus newnesi (Boulenger, 1902). mRNA levels were also assessed in fish exposed to 1.5 μg/L of perfluoro-octanoic acid for 10 days. The kidney showed a higher level of expression than the liver in wildlife specimens. In the liver, the treatment induced an increase in gene expression for all the considered enzymes, whereas in the kidney, it induced a general decrease. The obtained results advance the scientific community’s understanding of how the potential future presence of anthropogenic contaminants in the Southern Ocean can affect the antioxidant system of Antarctic fishes. The presence of pollutants belonging to the perfluoroalkyl substances in the Southern Ocean needs to be continuously monitored in parallel with this type of research

An Experimental Study on Antioxidant Enzyme Gene Expression in Trematomus newnesi (Boulenger, 1902) Experimentally Exposed to Perfluoro-Octanoic Acid

Antarctica is the continent with the lowest local human impact; however, it is susceptible to pollution from external sources. Emerging pollutants such as perfluoroalkyl substances pose an increasing threat to this environment and therefore require more in-depth investigations to understand their environmental fate and biological impacts. The present study focuses on expression analysis at the transcriptional level of genes coding for four antioxidant enzymes (sod1, sod2, gpx1, and gpx4) in the liver and kidney of an Antarctic fish species, Trematomus newnesi (Boulenger, 1902). mRNA levels were also assessed in fish exposed to 1.5 &mu;g/L of perfluoro-octanoic acid for 10 days. The kidney showed a higher level of expression than the liver in wildlife specimens. In the liver, the treatment induced an increase in gene expression for all the considered enzymes, whereas in the kidney, it induced a general decrease. The obtained results advance the scientific community&rsquo;s understanding of how the potential future presence of anthropogenic contaminants in the Southern Ocean can affect the antioxidant system of Antarctic fishes. The presence of pollutants belonging to the perfluoroalkyl substances in the Southern Ocean needs to be continuously monitored in parallel with this type of research

Social buffering of oxidative stress and cortisol in an endemic cyprinid fish

Abstract Fish exhibit complex social behaviours that can influence their stress levels and well-being. However, little is known about the link between social interactions and stress in wild fish, especially in running water environments. While many studies have explored the stress axis in fish, most have focused on specific social contexts, leaving gaps in understanding stress responses to social changes. Our study investigated collective behaviour and stress in wild Italian riffle dace (Telestes muticellus) in a controlled experimental setup simulating a natural river system. Results reveal that group-living fish have lower cortisol and oxidative stress levels in muscle tissue compared to solitary counterparts, suggesting a calming effect of conspecific presence. Additionally, we observed upregulated expression of antioxidant enzymes in group-living fish, indicating potential benefits to antioxidant defence systems. These insights shed light on the dynamic relationship between group behaviour and stress in wild fish within running water habitats and emphasise the use of multidisciplinary approaches