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With mounting pressure of heavy metal pollution on agriculture, the demand of practical tools and protocols for nondestructive, pre-visual detection of plant response towards heavy metals has received great impetus. Advances in modern spectroscopic techniques such as synchrotron radiation X-ray fluorescence and attenuated total reflectance Fourier transform infrared spectroscopy have the capability of providing a complete picture of the metabolic events taking place in plants stressed with heavy metals without subjecting the sample to pre-processing. The present study explores the utility of synchrotron radiation X-ray fluorescence and attenuated total reflectance Fourier transform infrared spectroscopy along with multivariate analysis for the detection of the response as spectral indices of wheat seedlings towards chromium treatment. For this, wheat has been grown under optimized growth conditions and exposed to chromium at concentrations from 20 to 100 µM. The synchrotron radiation X-ray fluorescence spectra of control and chromium exposed seedlings show that exposure to chromium leads to its accumulation in the leaves of wheat seedlings which results in a reduction of the uptake of calcium, potassium, manganese iron, copper and zinc by the seedlings. The alterations in the biochemicals of wheat seedlings as a result of chromium exposure have been assessed by attenuated total reflectance Fourier transform infrared spectroscopy. Analysis of the infrared data reveals that chromium significantly alters the spectral signatures of cellulose, pectin, hemicelluloses, lignin, amide II, amide I and lipid in the leaves of wheat seedlings. The observed changes are dependent on the dose of chromium. The spectral signatures obtained in this study serve as important monitoring indices for observing alterations in the physiological, biochemical and metabolic status of plants under heavy metal stress. [ABSTRACT FROM AUTHOR]

The goal of the current study is to characterize the changes in the biochemical composition of the leaves of wheat seedlings stressed by arsenic at concentrations of 0.2, 0.3, 0.4, and 0.5 mM using laser induced chlorophyll fluorescence and attenuated total reflectance Fourier transform infrared spectroscopy. The chlorophyll fluorescence spectra of the leaves of control and arsenic treated wheat seedlings showed increase in the intensity and intensity ratios of chlorophyll fluorescence bands indicating decrease in the photosynthesis performance and chlorophyll content of the leaves of wheat seedlings treated with arsenic. The infrared spectra of the leaves of control and arsenic treated wheat seedlings were obtained from 4000 to 485 cm−1 at a resolution of 4 cm−1. Multivariate principle component analysis of the preprocessed spectra suggest significant biochemical discrimination between the control and arsenic treated seedlings. Arsenic treatment decreased the concentration of cellulose while increasing the pectin, hemicellulose, xyloglucan, and lignin levels in the wheat seedling leaves. The exposure to arsenic also increased the spectral signatures of α-helix, β-sheet, amino acids, glutathione, lipids, and carboxyl compounds. These changes in the biochemicals indicate their physiological roles in mediating arsenic stress in wheat seedlings. The study also demonstrates the applicability of spectroscopic techniques for the non-invasive and rapid monitoring of the metabolism and physiology of the vegetation stressed by metals and metalloids before visual signs of toxicity appear. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the role of kangaroo mother care (KMC) on growth and breast feeding rates in very low birth weight (VLBW) neonates.Materials and Methods: A literature search was done to identify eligible studies using various electronic database searches including PubMed and EMBASE, various Web of Science including Scopus, Index Copernicus, African Index Medicus (AIM), Thomson Reuters (ESCI), Chemical Abstracts Service (CAS), SCIWIN (Scientific World Index), Google Scholar, Latin American and Caribbean Health Sciences Information System (LILACS), Index Medicus for the Eastern Mediterranean Region (IMEMR), Index Medicus for the South-East Asian Region (IMSEAR), and Western Pacific Region Index Medicus (WPRIM) and various clinical trial registries.Results: Thirteen studies that evaluated the role of KMC in VLBW infants in improvement of growth outcome (weight/length/head circumference) or breast feeding rates as their primary or secondary outcome, were included in this systematic review. Seven studies evaluated both growth and breast feeding rates, four studies evaluated breast feeding rates and two studies evaluated growth outcome. All included studies except one either showed positive effect or no effect on growth and breast feeding rates.Conclusions: KMC has a positive effect on growth of the VLBW infants and also leads to increase in the breast-feeding rates. KMC should be an integral part of neonatal care and should be promoted as an essential newborn care component. [ABSTRACT FROM AUTHOR]

A new class of 4-oxo-4 H-1-benzopyran derivatives were synthesized and their antiproliferative activity examined against a panel of three human cancer cell lines, that is, breast carcinoma (MDA-MB-468), ovarian adenocarcinoma (SK-OV-3), and colorectal adenocarcinoma (HT-29). Two compounds, that is, 3-hexyl-7,8-dihydroxy-4-oxo-4 H-1-benzopyran and ( E)-ethyl 3-(7-methoxy-4-oxo-4 H-1-benzopyran-3-yl)acrylate were found to be potent against all three cancer cell lines studied at 50 μM concentration. Also, the inhibitory potency of the compounds was evaluated against active Src kinase. A few of these compounds exhibited modest Src kinase inhibitory activity (IC50 = 52-57 μM). studies with respect to the nature and position of substituents on the could be further exploited for the design and development of more potent antiproliferative agents and/or Src kinase inhibitors. [ABSTRACT FROM AUTHOR]

Catalytic oxidation of styrene was investigated over polymer- and nonpolymer-anchored Cu(II) and Mn(II) complex catalysts prepared by schiff base tridentate ligands. The effect of temperature, styrene to H2O2 mole ratio and catalyst amount on the catalytic activity and product selectivity was investigated. Further, the catalysts were characterized by various techniques, such as elemental analysis, atomic absorption spectroscopy (AAS), FTIR, FE-SEM, EDAX, TGA, and UV-vis spectrophotometer. The elemental analysis, EDAX and AAS results confirmed the formation of Cu(II) and Mn(II) complexes, and it was found that the metal loading in the polymer-anchored complex catalysts were in the range of 0.53-3.74 %. FTIR results showed the co-ordination bond formation between the polymer ligands and metal ion. The catalytic data showed that, over all the catalysts, the main reaction products were benzaldehyde, styrene oxide, and benzoic acid. The polymer-anchored complex catalysts were found to be much more active when compared with nonpolymer-anchored catalysts. The maximum conversion of styrene (92.3%) was obtained over PS-[Cu(Hfsal-aepy)Cl] catalyst with benzaldehyde selectivity to 69% at the styrene to H2O2 mole ratio of 1 : 4 at 75°C. Although the PS-[Mn(Hfsal-aepy)Cl] catalyst was less active, it was highly selective to benzaldehyde. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Catalytic oxidation of styrene was investigated for polymeranchoredCu(II) and Mn(II) complexes prepared by Schiff base tridentate ligand.The effect of different oxidants, tert-butyl hydroperoxide(TBHP) under atmospheric pressure and molecular oxygen (O2) at high pressure in a batch reactor, were studied for maximum conversionof styrene and selectivity of styrene oxide product. The effect ofvarious reaction parameters such as temperature, styrene to TBHP moleratio, and catalyst amount were studied using TBHP as oxidant. Themaximum conversion of styrene (87.3%) was obtained using Cu(II) complex,with maximum selectivity to styrene oxide (76.2%) at styrene to TBHPmole ratio of 1:3, 70 °C, and 25 mg catalyst. The O2oxidant showed maximum conversion of 45.5% at 80 °C and 0.5MPa pressure, with a styrene oxide selectivity of 22.4%. The catalyticactivity was improved to 70.0% by addition of TBHP as initiator duringthe use of O2oxidant. The Cu(II) catalyst showed bettercatalytic activity in comparison to Mn(II) catalyst using both TBHPand O2oxidant. [ABSTRACT FROM AUTHOR]

An active composite of nitrogen-doped graphene oxide (N-rGO) supported gadolinium doped bismuth ferrite (BGFO), (BGFO/N-rGO), was synthesized by a modified hydrothermal method. The composite was characterized by X-ray photoelectron spectroscopy (XPS), fourier transform-infrared (FT-IR), diffused reflectance spectroscopy (DRS), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron spectroscopy (TEM), electrical impedance spectroscopy (EIS), photoluminescence (PL) and mott-schottky (M-S) analysis. Doping of Gd in pristine bismuth ferrite suppressed photoinduced electron-hole pair recombination. This resulted in a significant increase in the photocatalytic activity of BGFO (k = 7.89 gcat-1.h-1) in comparison to bare bismuth ferrite (k = 3.15 gcat-1.h-1) on the degradation of RhB. Further, incorporation of N-rGO with BGFO lead to the formation of a heterojunction that provided high surface area and a passage to transfer the electrons from BGFO to N-rGO. This further reduced the electron-hole pair recombination and improved the photocatalytic degradation of rhodamine B by 600% (k = 18.91 gcat-1.h-1) due to the availability of sufficient charge carriers at the surface of the catalyst. Superoxide ion (O 2−•) was found most active radical among the various reactive species viz. hydroxyl ion (OH•), electron (e-), and hole (h+) as confirmed by trapping experiments. A proposed mechanism of the degradation process was elucidated by species trapping experiments. • N-rGO supported BGFO heterojunction was synthesized by hydrothermal method. • Chemical interaction between BGFO and N-rGO was analyzed. • N-rGO support enhanced electron conductivity and charge carrier density significantly. • BGFO/NrGO showed high potential for photocatalytic degration of RhB. • Possible mechanism of RhB degradation was proposed. [ABSTRACT FROM AUTHOR]

Various heterogeneous polymerization techniques such as suspension, emulsion, dispersion, precipitation and seeded are employed for the synthesis of a wide variety of porous polymer particles. In present review, suspension polymerization technique is highlighted in detail with control of particle size, advantages and its applications. The aim of the review is to understand the basics of suspension polymerization for the synthesis of polystyrene cross-linked with divinylbenzene copolymer. Also, the effect of various synthesis parameters (agitation speed, temperature, initiator, cross-linker and diluent) on particle surface morphology, particle size and distribution, surface area and cross-linking density was reviewed and their application as catalyst support for various oxidation reactions. [ABSTRACT FROM AUTHOR]

This research used hydrothermal technique to synthesize three different morphologies of SBA-15 supports, such as rod, hexagonal prism, and spherical. Afterward, it impregnated Pt/Ce metal on the SBA-15 supports via wet-impregnation methods and investigated their NO reduction activity using the H2-SCR technique in the temperature range of 50–450℃. The catalysts were characterized by Brunauer-Emmett-Teller (BET), X-Ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Scanning electron microscopy, energy dispersive X-ray spectroscopy (SEM-EDS), Transmission electron microscopy (TEM), and Raman spectroscopy. Among the catalysts, Pt/Ce-SBA-15-rod exhibited the best performance with NO conversion of 52.23% and N2 selectivity of more than 83.25% at 150℃. The Pt/Ce-SBA-15-rod catalysts’ activation energy (21.188 kJ-mol− 1) was the lowest of all the catalysts. The catalysts with the highest NO conversion have the highest BET properties, surface oxygen (30.33%), Ce3+ (40.23%), Pt (0) (70.45%), and oxygen storage capacity. [ABSTRACT FROM AUTHOR]

Precise spatiotemporal and cell type-specific gene expression is essential for proper tissue development and function. Transcription factors (TFs) guide this process by binding to developmental stage-specific targets and establishing an appropriate enhancer landscape. In turn, DNA and chromatin modifications direct the genomic binding of TFs. However, how TFs navigate various chromatin features and selectively bind a small portion of the millions of possible genomic target loci is still not well understood. Here we show that Cdx2 - a pioneer TF that binds distinct targets in developing versus adult intestinal epithelial cells - has a preferential affinity for a non-canonical CpG-containing motif in vivo . A higher frequency of this motif at embryonic and fetal Cdx2 target loci and the specifically methylated state of the CpG during development allows selective Cdx2 binding and activation of developmental enhancers and linked genes. Conversely, demethylation at these enhancers prohibits ectopic Cdx2 binding in adult cells, where Cdx2 binds its canonical motif without a CpG. This differential Cdx2 binding allows for corecruitment of Ctcf and Hnf4, facilitating the establishment of intestinal superenhancers during development and enhancers mediating adult homeostatic functions, respectively. Induced gain of DNA methylation in the adult mouse epithelium or cultured cells causes ectopic recruitment of Cdx2 to the developmental target loci and facilitates cobinding of the partner TFs. Together, our results demonstrate that the differential CpG motif requirements for Cdx2 binding to developmental versus adult target sites allow it to navigate different DNA methylation profiles and activate cell type-specific genes at appropriate times.

Upgraded fuel oil was produced from the waste expanded polystyrene (WEPS) using pyrolysis and in-situ selective aromatization in a specially designed reactor. The catalytic pyrolysis of WEPS was performed keeping the catalyst in three different types of catalyst arrangements inside the reactor i.e., A-type/catalyst in liquid phase, B-type/catalyst in vapour phase, and AB-type or Multiphase/catalyst in both liquid and vapour phases, respectively. The ZSM-5 ammonium powder was used as a catalyst with varying feed to catalyst ratio and 20:1 was found to be optimum. Aromatics of fuel range like benzene, toluene, and ethylbenzene (BTE) were significantly increased and styrene got reduced by many folds when AB-type/multiphase catalytic pyrolysis was performed. The thermal pyrolysis produced maximum liquid yield of 94.37 wt% at a temperature of 650 °C and a heating rate of 15 °C/min. The maximum liquid yield of 88.05 wt%, 78.85 wt%, and 75.11 wt% were obtained for the A-type, B-type, and AB-type catalytic pyrolysis at the temperature of 600 °C, 550 °C and 550 °C, respectively using the same heating rate. The liquid oil of thermal pyrolysis contains very low amount of fuel range aromatics i.e., BTE of 11.38 wt% and the highest amount of styrene (84.74 wt%). In contrarily, BTE content for the catalytic process increased progressively in the order of 18.98 wt% (A-type) < 24.27 wt% (B-type) < 28.12 wt% (AB-type). The styrene content significantly decreased to a very low value of 46.30 wt% for AB-type/multiphase pyrolysis at the temperature of 550 °C., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Nanoparticle-facilitated drug delivery forms the core of medicine nowadays with the drug being delivered right at the target, reducing side effects and enhancing therapeutic value. Nanoparticles derived from natural compounds are further a point of focus being biocompatible and safe by and large. In this study, we have performed HF/6-31G calculations coupled with intermolecular interaction calculations and nanoscale molecular dynamics simulations to investigate self-assemblage in curcumin induced by trigonelline. Similar to recently reported self-assemblage in curcumin induced by sugar, trigonelline, a natural antidiabetic derived from fenugreek, can also induce auto-catalyzed self-assemblage in curcumin to form nanoparticles. It has been shown that these nanoparticles may be utilized for the delivery of drugs with severe side effects especially for diabetic patients with triple benefit of being antidiabetic, biocompatible and safe. As an example, carriage of antidiabetic drug pioglitazone and anticancer drug taxol have been depicted utilizing nanoparticles of curcumin and trigonelline. Twenty five taxol molecules could be comfortably carried in a 50 nm nanoparticle with an average overall root mean square deviation of 2.89 Å with reference to initial positions. For the first time, this study shows the possibility of developing antidiabetic nanoparticles with plethora of opportunities for diabetic patients. The study is expected to motivate experimental verification and has a long lasting impact in medicinal chemistry., Competing Interests: Conflict of interestOn behalf of all authors, the corresponding author states that there is no conflict of interest., (© King Abdulaziz City for Science and Technology 2020.)

Competing Interests: The authors declare that they have no conflict of interest.Informed consent was obtained from the patient.Ethical clearance for the study was obtained from IRB (Institutional Hospital Review Board), Bokaro General Hospital.

Tyrosine phosphorylation has emerged as an important regulator of plasma membrane-localized immune receptors activity. Here, we investigate the role of tyrosine phosphorylation in the regulation of rice XANTHOMONAS RESISTANCE 21 (XA21)-mediated immunity. We demonstrate that the juxtamembrane and kinase domain of Escherichia coli -expressed XA21 (XA21JK) autophosphorylates on tyrosine residues. Directed mutagenesis of four out of the nine tyrosine residues in XA21JK reduced autophosphorylation. These sites include Tyr 698 in the juxtamembrane domain, and Tyr 786 , Tyr 907 , and Tyr 909 in the kinase domain. Rice plants expressing XA21-GFP fusion proteins or proteins with these tyrosine residues individually mutated to phenylalanine (XA21 YF -GFP), which prevents phosphorylation at these sites, maintain resistance to Xanthomonas oryzae pv. oryzae . In contrast, plants expressing phosphomimetic XA21 variants with tyrosine mutated to aspartate (XA21 YD -GFP) were susceptible. In vitro purified XA21JK Y698F , XA21JK Y907F , and XA21JK Y909F variants are catalytically active, whereas activity was not detected in XA21JK Y768F and the four XA21JK YD variants. We previously demonstrated that interaction of XA21 with the co-receptor OsSERK2 is critical for biological function. Four of the XA21JK YF variants maintain interaction with OsSERK2 as well as the XA21 binding (XB) proteins XB3 and XB15 in yeast, suggesting that these four tyrosine residues are not required for their interaction. Taken together, these results suggest that XA21 is capable of tyrosine autophosphorylation, but the identified tyrosine residues are not required for activation of XA21-mediated immunity or interaction with predicted XA21 signaling proteins., Competing Interests: Pamela C. Ronald is an Academic Editor for PeerJ.

Due to the limited array of the currently available copper chelators, research of such compounds continues to be of clinical interest. Notably, o-dihydroxycoumarins have been previously shown to be potent iron chelators under neutral conditions. Within this study, the interaction of a series of natural coumarins and their synthetic analogs with copper has been evaluated in order to obtain structure-activity relationships under different pathophysiological pH conditions. Both competitive and non-competitive methods have been employed. Analysis of cupric ion reduction has also been performed. Under mildly competitive conditions, cupric chelation was observed for o-dihydroxycoumarins, and partially for o-diacetoxycoumarin. Non-competitive studies showed that cuprous ions are not chelated at all and that the stoichiometries of the most active 6,7- and 7,8-dihydroxycoumarins to cupric ions ranged from 1:1 to 2:1 depending on pH and concentration. Interestingly, under highly competitive conditions, coumarins were not capable of chelating cupric ions, either. Reduction experiments have shown that 13 out of the 15 coumarins included in this study reduced cupric ions. However, significant differences depending on their structures were apparent in their potencies. O-dihydroxycoumarins were the most potent ones again., Conclusion: O-dihydroxycoumarins are moderately active cupric ion chelators with potent copper reducing properties., (Copyright © 2017 Elsevier GmbH. All rights reserved.)