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Hepatic angiosarcoma is an uncommon primary malignancy of the liver. It carries a poor prognosis because of very aggressive nature of the tumor. Clinical presentation of hepatic angiosarcoma is variable, most common being hepatomegaly or abdominal mass. Here we report a case of primary hepatic angiosarcoma presented with spontaneous rupture and hemoperitoneum, which was managed successfully by transarterial embolization. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mechanism by which bitter gourd repels insects is poorly known. • Drosophila – model to understand the neurophysiology of aversion to phyto-extracts. • Bitter gourd extract affects viability of developing flies, but not adults. • Bitter gourd extract – antifeedant sensed through bitter sensitive taste neurons. • Bitter gourd extract reinforces aversive memory (retained even after 24 h). Bitter gourd (Momordica charantia L.) has compounds that repel insect pests. Unlike conventional pesticides, these compounds are eco-friendly and beneficial for human health. However the mechanisms by which these compounds repel insects and affect their physiology remains poorly known. Here we used Drosophila melanogaster (Meigen) to address these issues. We tested a wild strain, and a laboratory bred Canton S strain. Bitter gourd extract reduced the viability of developing flies, but did not affect survival in adults. Flies avoided bitter gourd extract in a food choice assay, and consumed a significantly low amount of food mixed with bitter gourd – indicating that it acts as an antifeedant. Transgenic flies with impaired aversive taste sensitive neurons showed a reduced aversion towards bitter gourd extract showing that these compounds act through the bitter sensitive gustatory neurons. Finally, flies also retained the memory of consuming bitter gourd extract for at least 24 hours, suggesting an additional cognitive mechanism for long term aversion. Our study provides the first evidence of bitter gourd compounds acting as antifeedants and also as potent reinforcers of aversive memory in drosophilids. We suggest that flies can be used to understand the physiological and neural mechanisms underlying the mode of action of other such phyto-extracts with the goal of developing potent but less harmful pest control formulations. [ABSTRACT FROM AUTHOR]

Abstract: In recent work, the GC-SAFT-VR equation, which combines the SAFT equation for potentials of variable range (VR) with a group contribution (GC) approach, was proposed. Parameters for key functional groups (such as CH3, CH2, CH, CH2 CH, C O, C6H5, ether, ester, OH, NH2, CH O, COOH) were obtained by fitting to experimental vapor pressure and saturated liquid density data for selected low molecular weight fluids and then used to predict the phase behavior of both pure non-associating and associating fluids and their mixtures, generally without adjusting the group parameters to binary mixture data. In the GC-SAFT-VR approach the benzene ring was modeled as a single group (C6H6 for benzene and C6H5, for alkylbenzenes) however, in common with other group-contribution based SAFT approaches, this approach fails to reproduce the correct curvature seen in the experimental liquid density of alkylbenzenes. In this work, to improve upon the model adopted for ring molecules, the benzene ring is explicitly considered through the connectivity of several smaller groups to more accurately capture the π–π interactions. We demonstrate that the improved model better captures the curvature present in the experimental saturated liquid density data of pure alkylbenzenes. Additionally, mixtures of several non-associating and associating fluids with benzene and alklybenzenes are studied. [Copyright &y& Elsevier]

Isomerization of aspartate to isoaspartate (isoAsp) on aging causes protein damage and malfunction. Protein- L -isoaspartyl methyltransferase (PIMT) performs a neuroprotective role by repairing such residues. A hexapeptide, Val-Tyr-Pro-(isoAsp)-His-Ala (VA6), a substrate of PIMT, is shown to form fibrils, while the normal Asp-containing peptide does not. Considering the role of PIMT against epileptic seizure, the combined effect of PIMT and two antiepileptic drugs (AEDs) (valproic acid and stiripentol) was investigated for anti-fibrillation activity. Structural/functional modulations due to the binding of AEDs to PIMT were investigated using biophysical techniques. Thioflavin T (ThT) fluorescence assay and microscopic methods were employed to study fibril formation by VA6. In vitro experiments with PC12 cells were carried out with PIMT/AEDs. ThT assay indicated reduction of fibrillation of VA6 by PIMT. AEDs stabilize PIMT, bind close to the cofactor binding site, possibly exerting allosteric effect, increase the enzymatic activity, and anti-fibrillation efficacy. Furthermore, Aβ42, implicated in Alzheimer's disease, undergoes β-sheet to α-helix transition in presence of PIMT. Studies with PC12 derived neurons showed that PIMT and PIMT/AEDs exerted neuroprotective effect against anti-NGF induced neurotoxicity. This was further validated against neurotoxicity induced by Aβ42 in primary rat cortical neurons. The study provides a new perspective to the role isoAsp in protein fibrillation, PIMT in its prevention and AEDs in enhancing the activity of the enzyme. IsoAsp, with an additional C atom in the main-chain of polypeptide chain, may make it more susceptible to fibrillation. PIMT alone, or in association with AEDs prevents this. Unlabelled Image • An isoAsp-containing hexapeptide, but not the corresponding one with Asp, forms fibril. • PIMT, the ubiquitous repair enzyme shows anti-fibrillation property. • Anti-fibrillation activity is enhanced in presence of AEDs. • Neuroprotective role against anti-NGF induced neurotoxicity was shown in PC12 cells. • IsoAsp, a β-amino acid, may be more prone to fibrillation than the α-amino acid. [ABSTRACT FROM AUTHOR]

Widespread use of gadolinium-based contrast agents in medical imaging has resulted in increased Gd inputs to municipal wastewater treatment plants. Others have reported that typical wastewater treatment does not attenuate Gd, resulting in discharges to natural waters. However, whether elevated Gd impacts the performance of biological treatment has not been investigated. We examined whether gadolinium chloride or Gd chelated with diethylenetriaminepentaacetic acid (DTPA) affected the activity of the model nitrifying bacterium Nitrosomonas europaea. At nominal GdCl 3 additions ranging from 1 to 500 μM, no impact was observed compared to the control. Most (>98%) of the added Gd precipitated, and extracellular GdPO 4 nanoparticles were observed. When chelated with DTPA, Gd remained soluble, but no statistically significant impact on ammonia oxidation was observed until the highest concentrations tested. At 300 and 500 μM Gd-DTPA, a temporary reduction of nitrite production relative to the control (effect size 1.3 mg l−1 and 1.5 mg l−1, respectively, at 24 h) was seen. By itself, DTPA was highly inhibitory. Modeling suggested that DTPA likely chelated other metals, but adjusting the concentrations of the most abundant metals in the medium, calcium and magnesium, indicated that lowering their free ion activities was probably not the cause of inhibition. Complexation of other essential metals was more likely. Our studies indicate that while the low bioavailability of Gd may limit its ecosystem impacts, the role of synthetic ligands used with Gd and other rare earth elements should be considered as the production, use and disposal of these elements increases. Image 1 • Gadolinium additions up to 500 μM did not inhibit N. europaea activity • Thermodynamic modeling suggested phosphate mineral precipitation • Extracellular Gd phosphate nanoparticles were observed • At high Gd-DTPA concentrations (≥300 μM) temporary inhibition occurred • Synthetic ligands used with rare earths may be more problematic than the metals [ABSTRACT FROM AUTHOR]