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Mechanical characterization of hydrogels and ultra-soft tissues is a challenging task both from an experimental and material parameter estimation perspective because they are much softer than many biological materials, ceramics, or polymers. The elastic modulus of such materials is within the 1 - 100 kPa range, behaving as a hyperelastic solid with strain hardening capability at large strains. In the current study, indentation experiments have been performed on agarose hydrogels, bovine liver, and bovine lymph node specimens. This work reports on the reliable determination of the elastic modulus by indentation experiments carried out at the macro-scale (mm) using a spherical indenter. However, parameter identification of the hyperelastic material properties usually requires an inverse finite element analysis due to the lack of an analytical contact model of the indentation test. Hence a comprehensive study on the spherical indentation of hyperelastic soft materials is carried out through robust computational analysis. Neo-Hookean and first-order Ogden hyperelastic material models were found to be most suitable. A case study on known anisotropic hyperelastic material showed the inability of the inverse finite element method to uniquely identify the whole material parameter set. [ABSTRACT FROM AUTHOR]

This study analyzed the concentrations of 15 (Al, As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, V, Zn) toxicologically important trace elements in the livers of 110 green turtles stranded in two areas of the Brazilian coast. These areas are essential for the refuge, feeding, and reproduction of the species, and the information obtained is intended to support the development of conservation strategies. Higher concentrations were observed in the Região dos Lagos, RJ in almost all elements, except for Al, Mo, Pb, and V. This location showed statistically higher differences in the concentrations of Cd (4.66 ± 2.33 μg.g−1), Fe (846.62 ± 583.06 μg.g−1), and Zn (27.17 ± 10.90 μg.g−1). The differences in trace element concentration patterns between the two study areas are likely influenced by multiple factors, including the bioavailability of trace elements, oceanic upwelling events, anthropogenic activities, habitat characteristics, and organism-specific metabolic processes. • Trace elements are mainly controlled by upwelling in the Brazilian coast. • As, Ba, Cd, Cu, Fe, Hg, Mn, Ni, Se and Zn had highest levels in the upwelling area. • Al, Cr, Mo, Pb had highest levels in area impacted by mine tailings. • Al, As, Cd, Cu, Fe and Zn showed highest levels in both study areas. • Ba, Cr, Ni and Pb were not detected (45 % of liver samples. [ABSTRACT FROM AUTHOR]

Previous results from genome wide association studies (GWASs) in chickens divergently selected for abdominal fat content of Northeast Agricultural University (NEAUHLF) showed that many single nucleotide polymorphism (SNP) variants were associated with abdominal fat content. Of them, six top significant SNPs at the genome level were located within SRD5A3 , SGCZ , DLC1 , GBE1 , GALNT9 and DNAJB6 genes. Here, expression levels of these six candidate genes were investigated in abdominal fat and liver tissue between fat and lean broilers from the 14th generation population of NEAUHLF. The results showed that expression levels of SRD5A3 , SGCZ and DNAJB6 in the abdominal fat and SRD5A3 , DLC1 , GALNT9 , DNAJB6 and GBE1 in the liver tissue differed significantly between the fat and lean birds, and were correlated with abdominal fat traits. The findings will provide important references for further function investigation of the six candidate genes involved in abdominal fat deposition in chickens. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the impact of chrome addition in diets of liver structure and oxidation prevention function in rabbit serum under heat stress.

Abstract: This study aims to experimentally determine the strain rate effects on the compressive stress–strain behavior of bovine liver tissues. Fresh liver tissues were used to make specimens for mechanical loading. Experiments at quasi-static strain rates were conducted at 0.01 and 0.1 s−1. Intermediate-rate experiments were performed at 1, 10, and 100 s−1. High strain rate (1000, 2000, and 3000 s−1) experiments were conducted using a Kolsky bar modified for soft material characterization. A hollow transmission bar with semi-conductor strain gages was used to sense the weak forces from the soft specimens. Quartz-crystal force transducers were used to monitor valid testing conditions on the tissue specimens. The experiment results show that the compressive stress–strain response of the liver tissue is non-linear and highly rate-sensitive, especially when the strain rate is in the Kolsky bar range. The tissue stiffens significantly with increasing strain rate. The responses from liver tissues along and perpendicular to the liver surface were consistent, indicating isotropic behavior. [ABSTRACT FROM AUTHOR]

In order to simulate the catadromous migration environment of the juvenile salmon (Oncorhynchus keta), five experimental groups containing different salinities (0, 5, 10, 15 and 20) were set up. The juvenile salmons with average body mass of (26.57±6.32) g and average full length of (14.44±1.05) cm were cultured for 130 days, and then the haematological biochemistrical indices was analyzed and the structure of liver tissue was observed to investigate the changes in physiological indices during the catadromous migration of juvenile salmon. The results showed that serum osmolality and the concentration of Na+, Cl- illustrated the same tendency with water salinity variation. Specifically, the serum Na+, Cl- and Mg2+ levels in the salinities of 15, 20 were significantly different from those in the salinity 5 and the freshwater and serum K+ in different salinities were all obviously lower than that in the freshwater . Also, the blood glucose level in salinity 10 was significantly higher than that in salinity 5 and 20, whereas total serum protein (TP), albumin (ALB) and globulin (GLB) levels all declined with the increase of salinity and the serum TP and GLB content in the freshwater group was remarkably higher than those in the salinity 15 and 20. There also existed an obvious discrepancy on total bile acids in freshwater group and the other salinity groups. The alanine aminotransferase (ALT) activity and aspartate aminotransferase (AST) activity in fresh water group were far different from those of the high salinity groups. Furthermore, in the low salinities (0 and 5), the liver cells of juvenile chum salmon partly broke down, and liver tissue was serious vacuolization. Collectively, the growth and survival rate had no significant difference in all groups and according to the physiological and biochemical indices, the appropriated salinity for juvenile chum salmon ranged from 10 to 20 during the catadromous migration. [ABSTRACT FROM AUTHOR]

Hepatitis E is chronic in immunocompromised patients with HIV infection, organ transplant, or radiation and chemotherapy. General cases are not chronic. Fifty-five cases were collected and followed up for 4–14 years. It was found that chronic hepatitis E is more common in males, but a high degree of inflammatory activity and fibrosis was not evident. After 4–14 years of follow-up observation, cirrhosis or liver cancer did not appear. This is significantly different from the hepatitis B and C viruses. We speculated that the chronic mechanism in the general patients with hepatitis E might be different from that of immunocompromised cases. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinomas (HCCs) are highly vascularized neoplasms with poor prognosis. Nanomedicine possesses great potential to deliver therapeutics and diagnostics. The new aspect of this study is that we have monitored, for the first time, the Raman responses to microtubule targeted vascular disrupting agents (MTVDA), MTVDA encapsulated non-targeted, and targeted cetuximab polymeric nanocomplexes delivery of combinatorial therapeutics in HCC tumor tissues of mice. Biochemical differences majorly demarcated apoptotic lipid bodies, and characteristic amide-I features. HCC tumor and healthy liver tissues could be stratified. Raman spectroscopy served as an excellent, rapid, sensitive and cost-effective approach for anticancer nanomedicine distinct stratification of MTVDA encapsulated targeted cetuximab polymeric nanocomplex combinatorials, a significant potential for HCC therapeutic monitoring. Rapid, high-throughput Raman spectroscopy exhibited complete discrimination of healthy liver and hepatocellular carcinoma (HCC) tumor tissues, and distinct stratification of anticancer nanomedicine in HCC treated tissues of mice. The unique Raman molecular signatures generated are useful for the rapid detection and evaluation of healthy and HCC tissues, and provide a new insight for HCC therapeutic drug monitoring. [Display omitted] • Raman spectroscopy completely discriminated healthy liver and HCC tumor tissues. • Depicts distinct stratification of anticancer nanomedicine treatment in HCC tissue. • Signifies significant advancement in HCC therapeutic intervention. [ABSTRACT FROM AUTHOR]

There is an evident need of low-cost vertebrates to be used in experimental carcinogenesis. Medaka (Oryzias latipes) provide a useful vertebrate model system for investigating tissue tropism of carcinogens and the action mechanisms of environmental contaminants posing a potential risk to human health. Juvenile medaka 2 months of age fed dietscontaining 100 ppm (dry weight basis) dibenzo[a,l]pyrene (DBP) for 28 days responded with hepatic neoplasia predominately of hepatocellular origin. When sampled 9 months following the termination of carcinogen exposure, medaka showed 26% incidence of neoplasia and 25% hepatic neoplasia, compared with 8% total neoplasia and 0% hepatic neoplasia in control fish. The predominant spontaneous neoplasms in this group of medaka were ovarian germ cell tumors. Hepatic neoplasia occurredat a higher incidence in female DBP-treated medaka than in males (11/29 vs 5/36). Nonneoplastic lesions observed in the livers of DBP-exposed fish included spongiosis hepatis, globular hyaline eosinophilic cytoplasmic inclusions in hepatocytes, foci of hepatocellular degeneration, extensive cytomegaly, and karyomegaly of hepatocytes. No activating exon I mutations in the one ras protooncogene examined were detected among six liver neoplasms. These results indicate that medaka are sensitive to the tumorigenic effects of the environmental carcinogen DBP, administered by dietary exposure. [ABSTRACT FROM AUTHOR]

Heavy metals such as (Cd) have been one of the most fundamental causes of soil and water pollution over the last three decades in industrial and early developed countries. We studied the impact of Cd on theliver metabolism of the frog Rana ridibunda by measuring the hepaticlevels of glycogen, lactate, total fat, protein, and glucose. Liver is one of the primary target organs of Cd accumulation. Frogs were exposed for 4, 10, and 30 days in 200 mg/liter of Cd (in the form CdCl2) dissolved in water. The level of glycogen in the liver increased until Day 10, with a slight decrease at Day 30. Lactate concentration was constant until Day 10 but then increased at Day 30. Liver fat content decreased from Day 10 to Day 30. Protein concentrationwas elevated at Day 10 but decreased to Day 30. Cd did not affect glucose concentration during the experiment. The frog appeared to face a metabolic stress over the first 10 days of Cd exposure. At the 30thday of Cd exposure, liver metabolism appeared to return to normal conditions, most probably due to activation of the defensive mechanismsof the organism against Cd toxicity. (c) 1999 Elsevier Science Ltd. [ABSTRACT FROM AUTHOR]

Laboratory experiments were carried out to investigate the relationship between hepatocytological changes and EROD activities in the demersal fish Solea ovato up to 7 days following intraperitoneal injection of 0.1, 0.5, 1, 5 and mg/kg benzo[a]pyrene (B[a]P). At 1 and 5 mg/kg of B[a]P, observable cytological alterations involved increase in abundance of lipofuscin granules, peroxisomes, mitochondria, lipid droplets and lysosomes, slight proliferation of the ER system, and glycogen depletion. At a higher dose (10 mg/kg) of B[a]P, condensation of cytoplasmic content was observed. Stereological analysis also showed apparent changes in hepatic lipofuscin granules, peroxisomes, mitochondria and lipids in response to B[a]P exposure. Experimental results demonstrated good dose-response relationship between exposure to B[a]P and changes in EROD activities. Numerical densities of hepatic lipofuscin granules and peroxisomes were significantly correlated with EROD activities (r = 0.84, 0.75, respectively, P< 0.1). The possible relationship between EROD induction, increases of lipofuscin granules and peroxisomes as a result of B[a]P exposure in S. ovata is discussed. The observed link between EROD induction and hepatocytological changes in response to toxicant exposure provides a more meaningful interpretation of EROD induction in ecotoxicological studies. (c) 1999 sevier Science Ltd. [ABSTRACT FROM AUTHOR]