Critical current density and magnetic phase diagram of BaFe1.29Ru0.71As2 Single Crystals

The critical current density has been measured on single crystals of Ru substituted BaFe2As2 superconductor at several temperatures and in fields up to 16 T. The magnetisation versus field isotherms reveal the occurrence of a clear second magnetisation peak (SMP) also known as fish-tail effect for both H parallel and perpendicular to c-axis of the crystal. The in-field resistance and magnetisation data are used to put forth a vortex phase diagram. The nature of the vortices have been determined from scaling behaviour of the pinning force density extracted from the Jc-H isotherms. The scaled JC versus reduced temperature behaviour seems to fit to a power law that indicates unambiguously that pinning in this system arises due to the spatial variation in the mean free path, viz. delta-l pinning

Antioxidant efficacy and cytotoxicity of ethanol extract of Clerodendrum infortunatum against different cell lines

572-581Clerodendrum infortunatum belongs to the Lamiaceae family and is a perennial shrub. It is widely known for their important medicinal values among the Mizo tribe. In the present study, the preliminary phytochemical screening, quantification of phenols, flavonoids and alkaloids, antioxidant activities by DPPH, O2- and ABTS assays and cytotoxicityby MTT assay against AGS (gastric cancer), HeLa (cervical) and HT-29 (colon) cell lines compared with normal cell line (Chang liver) were performed. Furthermore, the GC-MS profiling was also conducted. The results imply the presence of saponin, alkaloid, cardiac glycoside, phenol and flavonoid. The quantification shows that phenol content (64.35 mg/ g) was highest followed by flavonoid (61.93 mg/ g) and alkaloid (13.33 mg/ g). Its scavenging efficiency against DPPH with IC50 value was 47.99, against O2- with IC50 was108 µg/mL and against ABTS cations with IC50 was 50.05 µg/mL, respectively. The ethanol extract exhibited a maximum cytotoxicity against HeLa with IC50 value of 53.55 µg/mL, AGS with IC50 value 82.44 µg/mL and HT-29 with IC50 value of 142.2 µg/mL. However, the extract showed comparatively less toxicity against normal cell lines. Moreover, 14 active compounds were confirmed in the GC-MS analysis of the extract. HPLC study also infers the occurrence of the flavonoids rutin and quercetin. Therefore, the results of C. infortunatum ethanolic extract clearly specified that it has a very high antioxidant activity as well as cytotoxic properties; which proved that this ethnomedicinal plant can be used as an alternative agent to treat a variety of illnesses

Pharmaceutical Metabolism in Fish: Using a 3-D Hepatic In Vitro Model to Assess Clearance

At high internal doses, pharmaceuticals have the potential for inducing biological/pharmacological effects in fish. One particular concern for the environment is their potential to bioaccumulate and reach pharmacological levels; the study of these implications for environmental risk assessment has therefore gained increasing attention. To avoid unnecessary testing on animals, in vitro methods for assessment of xenobiotic metabolism could aid in the ecotoxicological evaluation. Here we report the use of a 3-D in vitro liver organoid culture system (spheroids) derived from rainbow trout to measure the metabolism of seven pharmaceuticals using a substrate depletion assay. Of the pharmaceuticals tested, propranolol, diclofenac and phenylbutazone were metabolised by trout liver spheroids; atenolol, metoprolol, diazepam and carbamazepine were not. Substrate depletion kinetics data was used to estimate intrinsic hepatic clearance by this spheroid model, which was similar for diclofenac and approximately 5 fold higher for propranolol when compared to trout liver microsomal fraction (S9) data. These results suggest that liver spheroids could be used as a relevant and metabolically competent in vitro model with which to measure the biotransformation of pharmaceuticals in fish; and propranolol acts as a reproducible positive control

Application of the rainbow trout derived intestinal cell line (RTgutGC) for ecotoxicological studies: molecular and cellular responses following exposure to copper.

There is an acknowledged need for in vitro fish intestinal model to help understand dietary exposure to chemicals in the aquatic environment. The presence and use of such models is however largely restrictive due to technical difficulties in the culturing of enterocytes in general and the availability of appropriate established cell lines in particular. In this study, the rainbow trout (Oncorhynchus mykiss) intestinal derived cell line (RTgutGC) was used as a surrogate for the "gut sac" method. To facilitate comparison, RTgutGC cells were grown as monolayers (double-seeded) on permeable Transwell supports leading to a two-compartment intestinal model consisting of polarised epithelium. This two-compartment model divides the system into an upper apical (lumen) and a lower basolateral (portal blood) compartment. In our studies, these cells stained weakly for mucosubstances, expressed the tight junction protein ZO-1 in addition to E-cadherin and revealed the presence of polarised epithelium in addition to microvilli protrusions. The cells also revealed a comparable transepithelial electrical resistance (TEER) to the in vivo situation. Importantly, the cell line tolerated apical saline (1:1 ratio) thus mimicking the intact organ to allow assessment of uptake of compounds across the intestine. Following an exposure over 72 h, our study demonstrated that the RTgutGC cell line under sub-lethal concentrations of copper sulphate (Cu) and modified saline solutions demonstrated uptake of the metal with saturation levels comparable to short term ex situ gut sac preparations. Gene expression analysis revealed no significant influence of pH or time on mRNA expression levels of key stress related genes (i.e. CYP3A, GST, mtA, Pgp and SOD) in the Transwell model. However, significant positive correlations were found between all genes investigated suggesting a co-operative relationship amongst the genes studied. When the outlined characteristics of the cell line are combined with the division of compartments, the RTgutGC double seeded model represents a potential animal replacement model for ecotoxicological studies. Overall, this model could be used to study the effects and predict aquatic gastrointestinal permeability of metals and other environmentally relevant contaminants in a cost effective and high throughput manner