RAINIER: A Simulation Tool for Distributions of Excited Nuclear States and Cascade Fluctuations

A new code has been developed named RAINIER that simulates the $\gamma$-ray decay of discrete and quasi-continuum nuclear levels for a user-specified range of energy, angular momentum, and parity including a realistic treatment of level spacing and transition width fluctuations. A similar program, DICEBOX, uses the Monte Carlo method to simulate level and width fluctuations but is restricted to $\gamma$-ray decay from no more than two initial states such as de-excitation following thermal neutron capture. On the other hand, modern reaction codes such as TALYS and EMPIRE populate a wide range of states in the residual nucleus prior to $\gamma$-ray decay, but do not go beyond the use of deterministic functions and therefore neglect cascade fluctuations. This combination of capabilities allows RAINIER to be used to determine quasi-continuum properties through comparison with experimental data. Several examples are given that demonstrate how cascade fluctuations influence experimental high-resolution $\gamma$-ray spectra from reactions that populate a wide range of initial states.Comment: 14 pages, 13 figures, Nuclear Instrumentation and Methods A, 201

Screening concepts, characterization and structural analysis of microbial-derived bioactive lipopeptides: a review

<p>Lipopeptide biosurfactants are surface active biomolecules that are produced by a variety of microorganisms. Microbial lipopeptides have gained the interest of microbiologists, chemists and biochemists for their high biodiversity as well as efficient action, low toxicity and good biodegradability in comparison to synthetic counterparts. In this report, we review methods for the production, isolation and screening, purification and structural characterization of microbial lipopeptides. Several techniques are currently available for each step, and we describe the most commonly utilized and recently developed techniques in this review. Investigations on lipopeptide biosurfactants in natural products require efficient isolation techniques for the characterization and evaluation of chemical and biological properties. A combination of chromatographic and spectroscopic techniques offer opportunities for a better characterization of lipopeptide structures, which in turn can lead to the application of lipopeptides in food, pharmaceutical, cosmetics, agricultural and bioremediation industries.</p

Apoptotic markers in PFII treated NHDFs.

<p>(A–C) [Ca²⁺]i fluorescence visualizations in cells as revealed by using an LSCM with fluorescent probe Fluo3/AM, scale bar - 100 µm. (D–F) Externalized phosphatidylserine by annexin V-fluorescein binding after PFII treatment, scale bar - 100 µm. Third (G–I) and fourth (J–L) panels show actin cytoskeletal organization and caspase-3 activation. Scale bar - 50 µm.</p

[Ca²⁺]<i>i</i> fluorescence visualizations and intensities in PFII-treated A375 cells.

<p>Intracellular calcium fluorescent signal in A375 cells as visualized by LSCM using the fluorescent probe Fluo-3/AM. (A) Control (untreated); (B–D) PFII for 24 h; (F) STS for 2 h. Scale bar - 100 µm.</p

Nuclear morphology of apoptotic A375 cells.

<p>(A) The nuclei of PFA fixed PFII treated cells were stained with Hoechst 33342 and analyzed by fluorescence microscopy. Arrows indicate apoptotic nuclei. Scale bar: 20 µm. (B) Agarose gel electrophoresis of DNA fragmentation of melanoma A375 cells. Lane 1, DNA marker; Lane 2, No treatment; Lane 3, 4, 5, PFII at concentration 65, 130 and 260 µM for 24 h, respectively. (C) As a positive control for DNA laddering melanoma A375 cells were treated with 1 µM staurosporine (STS) for 2 h. Lane 1, DNA marker; Lane 2, No treatment; Lane 3, STS. Control cells were treated with an equivalent amount DMSO to a final concentration of 1%.</p

Caspase-3 activation and actin cytoskeletal organization in melanoma A375 cells cultured in the presence of PFII.

<p>Cells were grown on glass coverslips in the presence of 65, 130, 260 µM or 1 µM staurosporine (STS). (A–E) Active caspase-3 was visualized with anti-active caspase-3 antibody followed by a FITC-conjugated secondary antibody (green). (F–J) Actin was visualized using laser scanning confocal microscope (LSCM) after staining with Alexa Fluor 568 - conjugated phalloidin (red). Scale bar - 50 µm.</p

Proliferation rate of melanoma A375, NHDF and NHEK cells measured by MTT assay.

<p>A375 cells (A), NHDF cells (B) and NHEK cells (C) were treated with 7–260 µM concentrations of PFII for 24 h or 48 h, incubated with MTT and the number of viable cells measured spectrophotometrically at 570 nm. The bars represent the means ± SD of triplicate values for three independent experiments. *0.05>P>0.01, **0.01>P>0.001, ***P<0.001.</p