Synthesis and antibacterial studies of lanthanide (III) complexes with aminopromazine

New complexes of lanthanide(III) nitrates with aminopromazine, having the general formula Ln(AP)(2)(NO3)(2)]NO3 (Ln = La, Cc, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and AP = aminopromazine) have been synthesised. The complexes have been screened far antibacterial activities

Assessment of wetland change dynamics of Chennai coast, Tamil Nadu, India, using satellite remote sensing

1258-1266The coastal wetlands of Chennai are increasingly being affected by anthropogenic factors, such as urbanization, residential, and industrial development. This study helps to monitor and map the dynamics of the coastal wetlands of Chennai using Landsat satellite images of 1988, 1996, 2006, and 2016 by following a supervised classification method. Post-classification wetland change detection was done in three temporal phases, that is, 1988 1996, 1996 2006, and 2006 2016. Change detection matrix analysis was performed to identify the from to changes. Ground truthing was carried out to validate the wetland classes. The overall accuracy of the classified image was 79.29% and the kappa coefficient was 0.7600. These results were imported into a GIS environment for further analysis. It was found that the wetlands have decreased to an alarming extent in the past 28 years from 23.14% in 1988 to 15.79% in 2016 of the total study area, owing to conversion of wetlands into industrial development, urban expansion, and other developmental activities

Classical Many-particle Clusters in Two Dimensions

We report on a study of a classical, finite system of confined particles in two dimensions with a two-body repulsive interaction. We first develop a simple analytical method to obtain equilibrium configurations and energies for few particles. When the confinement is harmonic, we prove that the first transition from a single shell occurs when the number of particles changes from five to six. The shell structure in the case of an arbitrary number of particles is shown to be independent of the strength of the interaction but dependent only on its functional form. It is also independent of the magnetic field strength when included. We further study the effect of the functional form of the confinement potential on the shell structure. Finally we report some interesting results when a three-body interaction is included, albeit in a particular model.Comment: Minor corrections, a few references added. To appear in J. Phys: Condensed Matte

REVIEW ON EVALUATING THE ROLE OF NSAIDS FOR THE TREATMENT OF ALZHEIMER'S DISEASE

Recently, several studies have been reported that nonsteroidal anti-inflammatory drugs can fight against neurodegenerative disorders by various mechanisms. Currently, available therapies of neurodegenerative disorders (NDs) provide only symptomatic relief. This is the point at which we need an alternative that acts on the root cause of disease. Parkinson’s disease and Alzheimer’s disease are the two NDs concentrated here. Since the drug profile is already known, drug repurposing is a promising technique in research, thereby reducing the cost and period effectively. Epidemiological studies on various nonsteroidal anti-inflammatory drugs (NSAIDs) showed good results, but when it came to clinical studies the results are found to be poor. Hence, it can be concluded that NSAIDs provide its neuroprotective activity on its long-term use only, as the brain accessibility of this kind of drug is poor due to its lower lipophilicity

Electron-phonon interaction contribution to the total energy of group IV semiconductor polymorphs: evaluation and implications

In density functional theory (DFT) based total energy studies, the van der Waals (vdW) and zero-point vibrational energy (ZPVE) correction terms are included to obtain energy differences between polymorphs. We introduce a new correction term, due to electron-phonon interactions (EPI). We rely on Allen's general formalism, which goes beyond the Quasi-Harmonic Approximation (QHA), to include the free energy contributions due to quasiparticle interactions. We show that, for semiconductors and insulators, the EPI contributions to the free energies of electrons and phonons are constant terms. Using Allen's formalism in combination with the Allen-Heine theory for EPI corrections, we calculate the zero-point EPI corrections to the total energy for cubic and hexagonal polytypes of Carbon, Silicon and Silicon Carbide. The EPI corrections alter the energy differences between polytypes. In SiC polytypes, the EPI correction term is more sensitive to crystal structure than the vdW and ZPVE terms and is thus essential in determining their energy differences. It clearly establishes that the cubic SiC-3C is metastable and hexagonal SiC-4H is the stable polytype. Our results are consistent with the experimental results of Kleykamp. Our study enables the inclusion of EPI corrections as a separate term in the free energy expression. This opens the way to beyond the QHA by including the contribution of EPI on all thermodynamic properties.Comment: Submitted for publication. 32 pages and 2 figure

Anti-angiogenic SPARC peptides inhibit progression of neuroblastoma tumors

<p>Abstract</p> <p>Background</p> <p>New, more effective strategies are needed to treat highly aggressive neuroblastoma. Our laboratory has previously shown that full-length Secreted Protein Acidic and Rich in Cysteine (SPARC) and a SPARC peptide corresponding to the follistatin domain of the protein (FS-E) potently block angiogenesis and inhibit the growth of neuroblastoma tumors in preclinical models. Peptide FS-E is structurally complex and difficult to produce, limiting its potential as a therapeutic in the clinic.</p> <p>Results</p> <p>In this study, we synthesized two smaller and structurally more simple SPARC peptides, FSEN and FSEC, that respectively correspond to the N-and C-terminal loops of peptide FS-E. We show that both peptides FSEN and FSEC have anti-angiogenic activity <it>in vitro </it>and <it>in vivo</it>, although FSEC is more potent. Peptide FSEC also significantly inhibited the growth of neuroblastoma xenografts. Histologic examination demonstrated characteristic features of tumor angiogenesis with structurally abnormal, tortuous blood vessels in control neuroblastoma xenografts. In contrast, the blood vessels observed in tumors, treated with SPARC peptides, were thin walled and structurally more normal. Using a novel method to quantitatively assess blood vessel abnormality we demonstrated that both SPARC peptides induced changes in blood vessel architecture that are consistent with blood vessel normalization.</p> <p>Conclusion</p> <p>Our results demonstrate that SPARC peptide FSEC has potent anti-angiogenic and anti-tumorigenic effects in neuroblastoma. Its simple structure and ease of production indicate that it may have clinical utility in the treatment of high-risk neuroblastoma and other types of pediatric and adult cancers, which depend on angiogenesis.</p

Rapid ultra-performance liquid chromatography assay of losartan potassium in bulk and formulations

Background: Losartan potassium is a non-peptide AT1 receptor drug used in the treatment of hypertension. Methods: A simple, rapid, sensitive, and validated isocratic reverse-phase ultra-performance liquid chromatographic (RP-UPLC) method was developed and validated for the determination of losartan potassium (LOS) in bulk drug and tablets. The assay was developed using Waters Acquity BEH C18 (100 mm × 2.1 mm), 1.7-μm column with a mobile phase consisting of a mixture of phosphate buffer (pH 3.2) and acetonitrile (50:50 v/v). Results: An assay with a total run time of only 5 min was developed. The method monitored at 245 nm exhibited linearity over a concentration range of 2.0 to 15.0 μg mL−1 LOS. The limits of detection and quantification (signal-to-noise ratio (S/N) = 10) were found be 0.018 and 0.054 μg mL−1 , respectively. The intraday and interday RSDs were less than 1.0%. The method was validated by the determination of LOS levels in tablets where the percentage on the label claim was 100 ± 2. The accuracy of the method was further ascertained by recovery studies via the standard addition procedure, which yielded satisfactory results. Conclusion: A rapid UPLC assay of LOS in bulk drug and tablets was developed and validated

Squeeze-and-Breathe Evolutionary Monte Carlo Optimisation with Local Search Acceleration and its application to parameter fitting

Motivation: Estimating parameters from data is a key stage of the modelling process, particularly in biological systems where many parameters need to be estimated from sparse and noisy data sets. Over the years, a variety of heuristics have been proposed to solve this complex optimisation problem, with good results in some cases yet with limitations in the biological setting. Results: In this work, we develop an algorithm for model parameter fitting that combines ideas from evolutionary algorithms, sequential Monte Carlo and direct search optimisation. Our method performs well even when the order of magnitude and/or the range of the parameters is unknown. The method refines iteratively a sequence of parameter distributions through local optimisation combined with partial resampling from a historical prior defined over the support of all previous iterations. We exemplify our method with biological models using both simulated and real experimental data and estimate the parameters efficiently even in the absence of a priori knowledge about the parameters.Comment: 15 Pages, 3 Figures, 6 Tables; Availability: Matlab code available from the authors upon reques

Enzymatic hydrolysis of market vegetable waste and subsequent ethanol fermentation-Kinetic evaluation

In this work, kinetic properties evaluation was made for bioethanol production from sugar hydrolysate of vegetable waste. The saccharified sugars were fermented by using Saccharomyces cerevisiae. The effect of various saccharification factors on sugars release were studied and observed that the optimized conditions contributed to 14.4 gL-1of fermentable sugars production. The produced sugars were subjected to batch fermentation by Saccharomyces cerevisiae at pH 4.5 and the kinetic parameters of fermentation were estimated by fitting the experimental data in modified logistic equations. The data revealed product (ethanol) yield (YP/S) of 0.39g/g of reducing sugars. Maximum specific growth rate (μmax), the yield of ethanol on biomass (YP/X) and the yield of biomass on sugars utilization (YX/S) were determined to be 0.18 h-1, 1.097 g/g and 0.313 g/g, respectively. The process yielded 4.13 gL-1 of ethanol by consumption of 10.6 gL-1 sugars with a volumetric production rate of 0.0861±0.002 gL-1 h-1

Modeling and Inferring Cleavage Patterns in Proliferating Epithelia

The regulation of cleavage plane orientation is one of the key mechanisms driving epithelial morphogenesis. Still, many aspects of the relationship between local cleavage patterns and tissue-level properties remain poorly understood. Here we develop a topological model that simulates the dynamics of a 2D proliferating epithelium from generation to generation, enabling the exploration of a wide variety of biologically plausible cleavage patterns. We investigate a spectrum of models that incorporate the spatial impact of neighboring cells and the temporal influence of parent cells on the choice of cleavage plane. Our findings show that cleavage patterns generate “signature” equilibrium distributions of polygonal cell shapes. These signatures enable the inference of local cleavage parameters such as neighbor impact, maternal influence, and division symmetry from global observations of the distribution of cell shape. Applying these insights to the proliferating epithelia of five diverse organisms, we find that strong division symmetry and moderate neighbor/maternal influence are required to reproduce the predominance of hexagonal cells and low variability in cell shape seen empirically. Furthermore, we present two distinct cleavage pattern models, one stochastic and one deterministic, that can reproduce the empirical distribution of cell shapes. Although the proliferating epithelia of the five diverse organisms show a highly conserved cell shape distribution, there are multiple plausible cleavage patterns that can generate this distribution, and experimental evidence suggests that indeed plants and fruitflies use distinct division mechanisms