Chalcones (1,3-diaryl-2-propen-1-ones) and their heterocyclic analogues, belong to the flavonoid family, which possess a number of interesting biological properties such as antioxidant, cytotoxic, ...anticancer, antimicrobial, antiprotozoal, antiulcer, antihistaminic and anti-inflammatory activities. Several pure chalcones have been approved for clinical use or tested in humans. Clinical trials have shown that these compounds reached reasonable plasma concentration and are well-tolerated. For this reason they are an object of continuously growing interest amongst the scientists. However, much of the pharmacological potential of chalcones is still not utilized. The purpose of this review is to provide an overview of the pharmacological activity of naturally occurring and synthetic chalcones. This review highlights more recent pharmacological screening of these compounds, their mechanisms of action and relevant structure-activity relationships.
Hole conducting, optically transparent Cu2O thin films on glass substrates have been synthesized by vacuum annealing (5×10−6 mbar at 700 K for 1 hour) of magnetron sputtered (at 300 K) CuO thin ...films. The Cu2O thin films are p-type and show enhanced properties: grain size (54.7 nm), optical transmission 72% (at 600 nm) and Hall mobility 51 cm2/Vs. The bulk and surface Valence band spectra of Cu2O and CuO thin films are studied by temperature dependent Hall effect and Ultra violet photo electron Spectroscopy (UPS). CuO thin films show a significant band bending downwards (due to higher hole concentration) than Cu2O thin films.
A small number of rare, recurrent genomic copy number variants (CNVs) are known to substantially increase susceptibility to schizophrenia. As a consequence of the low fecundity in people with ...schizophrenia and other neurodevelopmental phenotypes to which these CNVs contribute, CNVs with large effects on risk are likely to be rapidly removed from the population by natural selection. Accordingly, such CNVs must frequently occur as recurrent de novo mutations. In a sample of 662 schizophrenia proband-parent trios, we found that rare de novo CNV mutations were significantly more frequent in cases (5.1% all cases, 5.5% family history negative) compared with 2.2% among 2623 controls, confirming the involvement of de novo CNVs in the pathogenesis of schizophrenia. Eight de novo CNVs occurred at four known schizophrenia loci (3q29, 15q11.2, 15q13.3 and 16p11.2). De novo CNVs of known pathogenic significance in other genomic disorders were also observed, including deletion at the TAR (thrombocytopenia absent radius) region on 1q21.1 and duplication at the WBS (Williams-Beuren syndrome) region at 7q11.23. Multiple de novos spanned genes encoding members of the DLG (discs large) family of membrane-associated guanylate kinases (MAGUKs) that are components of the postsynaptic density (PSD). Two de novos also affected EHMT1, a histone methyl transferase known to directly regulate DLG family members. Using a systems biology approach and merging novel CNV and proteomics data sets, systematic analysis of synaptic protein complexes showed that, compared with control CNVs, case de novos were significantly enriched for the PSD proteome (P=1.72 × 10⁻⁶. This was largely explained by enrichment for members of the N-methyl-D-aspartate receptor (NMDAR) (P=4.24 × 10⁻⁶) and neuronal activity-regulated cytoskeleton-associated protein (ARC) (P=3.78 × 10⁻⁸) postsynaptic signalling complexes. In an analysis of 18 492 subjects (7907 cases and 10 585 controls), case CNVs were enriched for members of the NMDAR complex (P=0.0015) but not ARC (P=0.14). Our data indicate that defects in NMDAR postsynaptic signalling and, possibly, ARC complexes, which are known to be important in synaptic plasticity and cognition, play a significant role in the pathogenesis of schizophrenia.
The phenomenon of spontaneous spin reorientation phase transition (SRPT) in SmCrO
3
has been considered as a process comprising continuous rotation of magnetic moments of chromium ions. It is ...observed that in the vicinity of SRPT, the cooling and warming magnetic curves follow distinctly different paths and in the presence of low measuring fields this thermal irreversibility extends up to the Néel temperature marking a remarkable width of ∼163 K. Investigating the origin of thermal hysteresis and henceforth the nature of SRPT, we have qualitatively determined the phase fractions of phases involved in the transition. The thermal evolution of phase fraction closely resembles the theoretically predicted phase evolution in the well known Arvami model. The close resemblance suggests that the growth and nucleation mechanism across SRPT is similar to the crystallization process of solids from a supercooled liquid and further confirms the coexistence of two metastable phases in the neighborhood of SRPT. Moreover, the signatures of the magnetic glass like phase, which mainly arises due to the arrest of kinetics during a first order transition, are also noticed below T
SRPT
. These observations suggest the discontinuous Morin type nature of the spin reorientation process due to discrete flipping of Cr
3+
ions from the high temperature
Γ
4
to low temperature
Γ
1
configuration.
SmCrO
3
undergoes a discontinuous Morin type spin reorientation process due to discrete flipping of Cr
3+
ions from the high temperature
Γ
4
to low temperature
Γ
1
configuration.
Liquids are known to slip past non-wetting channel walls. The degree of slippage can be patterned locally through engineered variations in topography and/or chemistry. Electro-osmotic flow through a ...thin slit-like nanochannel with walls of sinusoidally varying slippage is studied through an asymptotic theory that uses the ratio of pattern amplitude to the average slip as a small parameter. The direction of patterning is perpendicular to the applied electric field. No restrictions are placed on the relative magnitudes of the channel height, wavelength of the pattern, the average slip length and the phase shift between the patterns on the walls. A closed-form analytical expression is provided for the effective slip length and tested against limits known from the literature. The results are also generalized for applicability to any unidirectional flow field that might originate from other driving forces such as pressure differential. The asymptotic results are compared with numerical simulations and are found to be in good mutual agreement even for moderate magnitudes of the small parameter in the asymptotic theory.
Alternative promoter usage and alternative splicing enable diversification of the transcriptome. Here we demonstrate that the function of Synaptic GTPase-Activating Protein (SynGAP), a key synaptic ...protein, is determined by the combination of its amino-terminal sequence with its carboxy-terminal sequence. 5' rapid amplification of cDNA ends and primer extension show that different N-terminal protein sequences arise through alternative promoter usage that are regulated by synaptic activity and postnatal age. Heterogeneity in C-terminal protein sequence arises through alternative splicing. Overexpression of SynGAP α1 versus α2 C-termini-containing proteins in hippocampal neurons has opposing effects on synaptic strength, decreasing and increasing miniature excitatory synaptic currents amplitude/frequency, respectively. The magnitude of this C-terminal-dependent effect is modulated by the N-terminal peptide sequence. This is the first demonstration that activity-dependent alternative promoter usage can change the function of a synaptic protein at excitatory synapses. Furthermore, the direction and degree of synaptic modulation exerted by different protein isoforms from a single gene locus is dependent on the combination of differential promoter usage and alternative splicing.
Indium oxide films are deposited by pulsed laser deposition in the presence of oxygen atmosphere, on different substrates, namely GaAs, Si, quartz, and glass. The structural, morphological, and ...interface characteristics are studied. Cubic In
2O
3 phase is confirmed by high resolution X-ray diffraction measurements. While the films on Si, glass, and quartz substrates are polycrystalline, the films on GaAs exhibit a preferred orientation along (2
2
2) plane. The structure and crystalline nature of the films are also confirmed by Raman spectroscopy. Furthermore, Raman spectra show the appearance of gallium oxide modes arising due to Ga diffusion from the substrate. The morphology of the films deposited on different substrates is studied by atomic force microscopy and
rms roughness values are obtained. A two-dimensional power spectral density analysis has been used to calculate the growth exponent (
α). A value of
α
>
1 (
α
<
1) for films grown on GaAs/Si (quartz/glass) substrates suggests that the growth on crystalline substrates is governed by the linear diffusion model, whereas the growth on amorphous substrates follows the dynamic scaling behaviour. UV–visible study shows a high optical transmittance of >90% and a band gap value of 3.64 and 3.79
eV for the films deposited on quartz and glass substrates, respectively.
K
Zr
2
PO
4
3
:
xEu
3
+
Nanophosphors with varying molar percentages (0.5, 1, 2, 3, 4, and 5 mol. %) are synthesized using a urea-assisted solution combustion synthesis approach. The phosphors ...exhibit crystallization in a rhombohedral phase, namely in the R
3
¯
c space group with the help of X-ray diffraction. The anionic group of (PO
4
)
3−
is responsible for all the vibrations occurring in the FTIR spectra. The photoluminescence characteristics of
K
Zr
2
PO
4
3
:
xEu
3
+
(
x
= 0.5 – 5 mol. %) are examined when excited at a wavelength of 392 nm, resulting in the prominent emission at 613 nm. At a concentration of 2 mol. %, the optimal concentration is observed, and the emission tone of the phosphor is centered in the reddish part of the color gamut, with a high color purity of 92%. It is observed that the synthesized phosphor has a branching ratio more than 50%, indicating a possible laser emission transition. The band gap energy of
K
Zr
2
PO
4
3
:
Eu
3
+
is found via diffuse reflectance measurements and found to be 4.19 eV. The value of metallization criteria is less than unity which dictates the non-metallic nature of the synthesized phosphors. These results indicate that this phosphor is very suitable for use in solid-state lighting applications as a red light-emitting phosphor.
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