Synergistic integration of ZrO2-enriched reduced graphene oxide-based nanostructures for advanced photodegradation of tetracycline hydrochloride.

The escalating demand for the antibiotic drug tetracycline hydrochloride (TCH) contributes to an increased release of its residues into land and water bodies, which poses risks to both aquatic life and human health. Therefore, it is precedence to effectively degrade TCH residues to protect environment from their long-term impacts. In this aspect, the present study entails the synthesis of zirconia (ZrO2) nanostructures and focuses on the enhancement in the catalytic performance of ZrO2 nanostructures by employing reduced graphene oxide (RGO) as a solid support to synthesize ZrO2-enriched RGO-based photocatalysts (ZrO2-RGO) for the degradation of TCH. The study delves into comprehensive spectroscopic and microscopic investigations and their photodegradation assessments. Powder XRD and HR-TEM studies depicted the phase crystallinity and also displayed uniform distribution of ZrO2 nanostructures with spherical morphology within ZrO2-RGO. This corresponds to high surface-to-volume ratios, providing a substantial number of active sites for light absorption and generation of e--h+ pairs. Moreover, the heterojunctions created between RGO and ZrO2 nanostructures promoted the interspecies electron transfer which prolonged the recombination time of e- and h+ than pure ZrO2 nanostructures, accounted for enhanced degradation of TCH using ZrO2-RGO. The photocatalytic activity of as-synthesized materials were examined under visible and UV light irradiation. The degradation efficiency of ~ 73.82% was achieved using ZrO2-RGO-based photocatalyst with rate constant k = 0.007023 min-1 under visible-light illumination. Moreover, under UV-light, the degradation rate was explicated to be k = 0.01017 min-1 with ~ 85.56% degradation of TCH antibiotics within 180 mins. Hence, the synthesized ZrO2-enriched RGO-based photocatalysts represents a promising potential for the effective degradation of pharmaceutical compounds, particularly TCH under visible and UV-light irradiation.

Advancements in Genetic and Biochemical Insights: Unraveling the Etiopathogenesis of Neurodegeneration in Parkinson's Disease.

Parkinson's disease (PD) is the second most prevalent neurodegenerative movement disorder worldwide, which is primarily characterized by motor impairments. Even though multiple hypotheses have been proposed over the decades that explain the pathogenesis of PD, presently, there are no cures or promising preventive therapies for PD. This could be attributed to the intricate pathophysiology of PD and the poorly understood molecular mechanism. To address these challenges comprehensively, a thorough disease model is imperative for a nuanced understanding of PD's underlying pathogenic mechanisms. This review offers a detailed analysis of the current state of knowledge regarding the molecular mechanisms underlying the pathogenesis of PD, with a particular emphasis on the roles played by gene-based factors in the disease's development and progression. This study includes an extensive discussion of the proteins and mutations of primary genes that are linked to PD, including α-synuclein, GBA1, LRRK2, VPS35, PINK1, DJ-1, and Parkin. Further, this review explores plausible mechanisms for DAergic neural loss, non-motor and non-dopaminergic pathologies, and the risk factors associated with PD. The present study will encourage the related research fields to understand better and analyze the current status of the biochemical mechanisms of PD, which might contribute to the design and development of efficacious and safe treatment strategies for PD in future endeavors.

Bio-mimetic selectivity in Hg2+ sensing developed via electro-copolymerized PEDOT and benzothiazole-Au nanoparticles composite.

To eliminate the potential health risks of mercury, development of stable and selective mercury sensor with high sensitivity is the need of the hour. To address this, a novel PEDOT-AA-BTZ-Au-based Hg2+ selective, hybrid electrochemical sensor has been designed by following a simple protocol for electrode fabrication. The electrode was designed by carefully optimizing the onset oxidation potential of supramolecule 2-(anthracen-9-yl)benzo[d]thiazole (AA-BTZ) and conducting polymer poly-(3,4-ethylenedioxythiophene) (PEDOT), using copolymerization approach followed by dropcasting of gold nanoparticles (AuNPs). The designed electrode offered synergistic effects thus augmenting the electrical conductivity and adsorption capacity as depicted by its porous surface morphology. The highly sensitive analytical signal was generated by sulphur pockets present in AA-BTZ and PEDOT conducting framework. This is further complemented by the selectivity offered by the soft interactions between AuNPs and Hg2+ resulting in a low detection limit of 0.60 nM. The prepared system was further utilized for sensing Hg2+ ion in real systems including lake water and cosmetic samples. Low interference from other ions and better reproducibility further established the suitability of the designed transducer system for future on-site sensing.

An Insight into Cellular and Molecular Mechanisms Underlying the Pathogenesis of Neurodegeneration in Alzheimer's Disease.

Alzheimer's disease (AD) is the most prominent neurodegenerative disorder in the aging population. It is characterized by cognitive decline, gradual neurodegeneration, and the development of amyloid-ß (Aß)-plaques and neurofibrillary tangles, which constitute hyperphosphorylated tau. The early stages of neurodegeneration in AD include the loss of neurons, followed by synaptic impairment. Since the discovery of AD, substantial factual research has surfaced that outlines the disease's causes, molecular mechanisms, and prospective therapeutics, but a successful cure for the disease has not yet been discovered. This may be attributed to the complicated pathogenesis of AD, the absence of a well-defined molecular mechanism, and the constrained diagnostic resources and treatment options. To address the aforementioned challenges, extensive disease modeling is essential to fully comprehend the underlying mechanisms of AD, making it easier to design and develop effective treatment strategies. Emerging evidence over the past few decades supports the critical role of Aß and tau in AD pathogenesis and the participation of glial cells in different molecular and cellular pathways. This review extensively discusses the current understanding concerning Aß- and tau-associated molecular mechanisms and glial dysfunction in AD. Moreover, the critical risk factors associated with AD including genetics, aging, environmental variables, lifestyle habits, medical conditions, viral/bacterial infections, and psychiatric factors have been summarized. The present study will entice researchers to more thoroughly comprehend and explore the current status of the molecular mechanism of AD, which may assist in AD drug development in the forthcoming era.

2-(Anthracen-9-yl)benzothiazole-modified graphene oxide-nickel ferrite nanocomposite for anodic stripping voltammetric detection of heavy metal ions.

A novel electrochemical sensor, 2-(anthracen-9-yl)benzothiazole (ABT)-modified nickel ferrite reduced graphene oxide (NF@rGO) has been designed for the individual and simultaneous detection of Cd2+, Cu2+, and Hg2+ ions. Herein, NF@rGO nanocomposite, synthesized by a simple hydrothermal methodology, was hooked to ABT under easy and simple stirring conditions. Chelation of active functional groups of ABT with metal ions was augmented with higher adsorption and conductivity provided by NF@rGO. The created synergy resulted in analytical signals via selective oxidation of the ions within a potential ranging from - 1.2 to + 1.2 V vs sat. KCl. The proposed protocol exhibited a wide linear range from 0.05 to 1250 nM with excellent detection limit of 123, 54.1, and 86.6 pM via anodic stripping voltammetry for the simultaneous determination of Cd2+, Cu2+, and Hg2+ ions, respectively. Simple cost-effective synthetic approach, improved sensitivity with high selectivity, noteworthy repeatability (RSD less than 3%), and reproducibility (RSD less than 7%) equipped with successful real time monitoring (apparent recovery more than 90%) bring about a spiffing sensing platform for the detection of hazardous metal ions.

The protective role of HSP27 in ocular diseases.

Heat shock proteins (HSPs) are stress-induced proteins that are important constituents of the cell's defense system. The activity of HSPs enhances when the cell undergoes undesirable environmental conditions like stress. The protective roles of HSPs are due to their molecular chaperone and anti-apoptotic functions. HSPs have a central role in the eye, and their malfunction has been associated with the manifestation of ocular diseases. Heat shock protein 27 (HSP27, HSPB1) is present in various ocular tissues, and it has been found to protect the eye from disease states such as retinoblastoma, uveal melanoma, glaucoma, and cataract. But some recent studies have shown the destructive role of HSP27 on retinal ganglionic cells. Thus, this article summarizes the role of heat shock protein 27 in eye and ocular diseases and will focus on the expression, regulation, and function of HSP27 in ocular complications.

RNA interference and crop protection against biotic stresses.

RNA interference (RNAi) is a universal phenomenon of RNA silencing or gene silencing with broader implications in important physiological and developmental processes of most eukaryotes, including plants. Small RNA (sRNA) are the critical drivers of the RNAi machinery that ensures down-regulation of the target genes in a homology-dependent manner and includes small-interfering RNAs (siRNAs) and micro RNAs (miRNAs). Plant researchers across the globe have exploited the powerful technique of RNAi to execute targeted suppression of desired genes in important crop plants, with an intent to improve crop protection against pathogens and pests for sustainable crop production. Biotic stresses cause severe losses to the agricultural productivity leading to food insecurity for future generations. RNAi has majorly contributed towards the development of designer crops that are resilient towards the various biotic stresses such as viruses, bacteria, fungi, insect pests, and nematodes. This review summarizes the recent progress made in the RNAi-mediated strategies against these biotic stresses, along with new insights on the future directions in research involving RNAi for crop protection.

Mobilization of storage lipid reserve and expression analysis of lipase and lipoxygenase genes in rice (Oryza sativa var. Pusa Basmati 1) bran during germination.

Storage lipid mobilization by lipases and lipoxygenases (LOXs) in response to developmental cues take place during seed germination. After rice grain milling, the endogenous lipases and LOXs present in the bran fraction come in contact with the storage lipid reserve or triacylglycerol (TAG). Lipases catalyze the hydrolysis of TAGs to non-esterified fatty acids (NEFAs) and glycerol. The NEFAs, especially linoleic acid (18:2) produced, are further subjected to oxidative rancidity via peroxidation reaction catalyzed by LOXs. This results in the production of conjugated hydroperoxides of 18:2 that influence the off-flavors in rice bran lipids. The aim of this study is to understand how lipid mobilization and expression of lipase and LOX genes occur in the bran of germinating rice grains (Oryza sativavar. Pusa Basmati 1). Our results show that the primary source of storage lipids in bran is TAG, and its mobilization starts at 4 days after imbibition (4 DAI). Using publically available RNA-seq data and phylogeny analyses, we selected a total of 18 lipase and 16 LOX genes in rice for their expression profiles during onset of lipid mobilization. Gene expression analyses revealed OsLip1, OsLip9, and OsLip13; and OsLOX3 and OsLOX14 as the predominantly expressed genes in bran of germinating rice grains. This study explores two important events in the germinating rice grains, namely, mobilization of storage lipids and expression pattern of lipase and LOX genes. The information generated in this study can be used to efficiently manipulate the genes to enhance the shelf-stability of bran lipid reserve.

MicroRNAs as potential targets for improving rice yield via plant architecture modulation: Recent studies and future perspectives.

Ensuring agricultural food security is a major concern for the future world, and being the second most consumed crop, rice yield needs an urgent upliftment. Grain yield is a pleiotropic trait that employs a plethora of genes functioning in complex signalling cascades. The yield related genes are controlled by various regulatory factors including the microRNAs (miRNAs), the small 20-22 nucleotide (nt) non-coding RNAs, which have emerged as the master ribo-regulators of eukaryotic genes. Plant miRNAs can bind to highly complementary sequences in the target messenger RNAs (mRNAs) and negatively regulate gene expression to coordinate the various biological processes involved in plant development. In rice, an ideal plant architecture (IPA) has been regarded as the key to attain high yield and several miRNAs have been deciphered to play important roles in orchestrating vital regulatory procedures for achieving optimum plant morphological yield related traits like less unproductive tillers, more panicle branches and heavier grains. In this review, we present and discuss the various genetic engineering strategies undertaken to manipulate the miRNA-mRNA expression levels in order to achieve improved grain output by modulation of rice plant architecture and recent advances made in this regard.

Electrochemical detection of methyl parathion via a novel biosensor tailored on highly biocompatible electrochemically reduced graphene oxide-chitosan-hemoglobin coatings.

A quick electrochemical sensing tool by utilizing novel bioelectrode based on redox active protein hemoglobin (Hb) has been offered here for the determination of methylparathion (MP). The bioelectrode has been designed by immobilizing Hb on electrochemically reduced graphene oxide-chitosan (ERGO-CS/Hb/FTO) based biocompatible coatings. Fourier transform-infrared analyses (FTIR), field emission scanning electron microscopy (FESEM), UV-visible and electrochemical characterization reveal the successful grafting of ERGO-CS/Hb/FTO. A detailed impedimetric analysis shows low charge transfer resistance (RCT) and solution resistance (Rs) for the fabricated biosensor, thus pointing towards improved electrochemical performance and sensitivity. In-depth elucidation of redox analysis has been presented in terms of surface concentration of redox moiety (2.92 × 10-9 mol cm-2) and heterogeneous electron transfer rate constant (0.0032 s-1) which indicate enhanced surface coverage and better charge transfer properties of the proposed electrochemical biosensor. The sensor is equipped with a low limit of detection of 79.77 nM and a high sensitivity of 45.77 Acm-2 µM-1 with excellent reproducibility. The modified biosensor also offered its credibility towards detection of MP in vegetable samples with recovery (%) ranging from 94% to 101%. The designed biosensor hereby, evolves as a promising approach for the recognition of MP.

Identification and functional characterization of two acyl CoA:diacylglycerol acyltransferase 1 (DGAT1) genes from forage sorghum (Sorghum bicolor) embryo.

Elevating the lipid content in high-biomass forage crops has emerged as a new research platform for increasing energy density and improving livestock production efficiency associated with improved human health beneficial meat and milk quality. To gain insights of triacylglycerol (TAG) biosynthesis in forage sorghum, two type-1 diacylglycerol acyltransferase (designated as SbDGAT1-1 and SbDGAT1-2) were characterized for its in vivo function. SbDGAT1-2 is more abundantly expressed in embryo and bran during the early stage of the grain development in comparison to SbDGAT1-1. Heterologous expression of SbDGAT1 genes in TAG deficient H1246 strain restored the TAG accumulation capability with high substrate predilection towards 16:0, 16:1 and 18:1 fatty acids (FA). In parallel, we have identified N-terminal intrinsically disordered region (IDR) in SbDGAT1 proteins. To test the efficacy of the N-terminal region, truncated variants of SbDGAT1-1 (designated as SbDGAT1-1(39-515) and SbDGAT1-1(89-515)) were generated and expressed in yeast H1246 strain. Deletion in the N-terminal region resulted in decreased accumulation of TAG and FA (16:0 and 18:0) when compared to the SbDGAT1-1 variant expressed in yeast H1246 strain. The present study provides significant insight in forage sorghum DGAT1 gene function, useful for enhancing the green-forage TAG content through metabolic engineering.

Multianalyte azo dye as an on-site assay kit for colorimetric detection of Hg2+ions and electrochemical sensing of Zn2+ ions.

A new tailor-made colorimetric chemosensor, (E)-1-(benzo[d]thiazol-2-yl)-3-(pyridin-3-yldiazenyl)naphthalen-2-ol (1), containing benzothiazole and pyridine moieties connected through an azo (-N=N-) linkage has been designed and synthesized. The synthesized chemosensor displayed an eye-catching color change upon binding to acetate [AcO-;colorless to russet] and mercury (II) [Hg2+;colorless to greenish blue] ions in 9:1 (v/v) aqueous CH3CN (pH 7.0 HEPES buffer).The mechanism of interaction between the chemosensor and the Hg2+/AcO- ions has been confirmed by 1H NMR titration experiments. Moreover, the colorimetric chemosensor 1 displayed potential in-field applications as on-site assay kit and detection of Hg2+ ions in real water samples. Importantly chemosensor 1 gave selective electrochemical response towards Zn2+ ions, enabling simple azo-dye 1 as multichannel chemosensor for colorimetric detection of Hg2+ ions and electrochemical detection of Zn2+ ions.

A Schiff base modified graphene oxide film for anodic stripping voltammetric determination of arsenite.

A protocol is described for chemical modification of graphene oxide with a Schiff base derived from diethylenetriamine and 2-hydroxy-4-methoxybenzophenone. The base was grafted onto an indium tin oxide (ITO) film and applied to electroanalytical determination of arsenite. Successful grafting was confirmed by Fourier transform-infrared spectroscopy, spectrophotometry, field emission scanning electron microscopy and cyclic voltammetry. Secondly, the coated ITO film served as a working electrode for the stripping voltammetric determination of arsenite. The analytical signal is generated by selective oxidation of metal species via multi-donor sites present in the derivatized Schiff base. The electroanalytical protocol was optimized by investigating the effects of deposition time, working potential, frequency and amplitude of square wave anodic stripping voltammetry. The method has attractive features including (a) the usage of a non-metallic, non-toxic and cost-effective material; (b) improved sensitivity (with limit of detection as low as 156 pM) due to better adsorption of arsenite in the Schiff base pockets on the ITO, and (c) the application to the determination of arsenite in real samples. Graphical abstract Schematic representation of the fabrication of a Schiff base-functionalized graphene oxide on an indium tin oxide (SB@SiO2@GO@ITO) electrode for selective electrochemical sensing of arsenite due to adsorption on multi-donor sites.

Can wheat survive in heat? Assembling tools towards successful development of heat stress tolerance in Triticum aestivum L.

Wheat is an important cereal crop that fulfils the calorie demands of the global humanity. Rapidly expanding populations are exposed to a fast approaching acute shortage in the adequate supply of food and fibre from agricultural resources. One of the significant threats to food security lies in the constantly increasing global temperatures which inflict serious injuries to the plants in terms of various physiological, biochemical and molecular processes. Wheat being a cool season crop is majorly impacted by the heat stress which adversely affects crop productivity and yield. These challenges would be potentially defeated with the implementation of genetic engineering strategies coupled with the new genome editing approaches. Development of transgenic plants for various crops has proved very effective for the incorporation of improved varietal traits in context of heat stress. With a similar approach, we need to target for the generation of heat stress tolerant wheat varieties which are capable of survival in such adverse conditions and yet produce well. In this review, we enumerate the current status of research on the heat stress responsive genes/factors and their potential role in mitigating heat stress in plants particularly in wheat with an aim to help the researchers get a holistic view of this topic. Also, we discuss on the prospective signalling pathway that is triggered in plants in general under heat stress.

Molecular Genetic Approaches for Environmental Stress Tolerant Crop Plants: Progress and Prospects.

BACKGROUND: Global food security is threatened by the severe environmental conditions that have reduced the worldwide crop yield. Plants possess inherent mechanisms to cope with the initial stress phase but to ensure their survival through harsh climate, the intervention of genetic engineering is desirable. OBJECTIVE: We present a comprehensive review on the progress made in the field of developing environmental stress tolerant crops and the prospects that can be undertaken for achieving it. METHODS: We review the effects of abiotic and biotic stresses on crop plants, and the use of different molecular genetic approaches to cope with these environmental stresses for establishment of sustainable agriculture. The various strategies employed in different crops have also been discussed. We also summarized the major patents in the field of plant stress tolerance that have been granted in the last five years. RESULTS: On the basis of these analyses, we propose that genetic engineering of crops is the preferred approach over the traditional methods for yielding healthier and viable agriculture in response to the different stressful environments. The wild progenitors of cultivated crop species can prove to be highly potential genetic resources in this regard and can be exploited to produce better crops that are relatively tolerant towards various environmental stresses. CONCLUSION: Thus, elucidation of genetic loci and deciphering the underlying mechanisms that confer tolerance to plants against stressful conditions followed by its successful introgression into elite, high-yielding crop varieties can be an effective way to engineer the crops for sustainable agriculture.

Molecular genetic approaches for environmental stress tolerant crop plants: Progress and prospects.

Global food security is threatened by the severe environmental conditions that have reduced the worldwide crop yield. Plants possess inherent mechanisms to cope with the initial stress phase but to ensure their survival through harsh climate, the intervention of genetic engineering is desirable. Elucidation of genetic loci and deciphering the underlying mechanisms that confer tolerance to plants against stressful conditions followed by its successful introgression into elite, high-yielding crop varieties can be an effective way to engineer the crops for increasing productivity. This review provides an overview about the effects of abiotic and biotic stresses on crop plants and the use of genetic engineering approach to cope with these environmental stresses for a sustainable agriculture. Major patents in the field of plant stress tolerance in the last five years have also been summarized.

Randomized controlled trial of tranexamic acid among parturients at increased risk for postpartum hemorrhage undergoing cesarean delivery.

OBJECTIVE: To assess the effects of tranexamic acid among patients undergoing cesarean delivery who were at high risk of postpartum hemorrhage. METHODS: Between August 1, 2012, and April 30, 2013, a randomized controlled trial was performed at a tertiary care center in India. Women undergoing an elective or emergency cesarean delivery who were at high risk for postpartum hemorrhage were enrolled. They were randomly assigned using sealed, opaque envelopes to receive 10mg/kg tranexamic acid or normal saline 10min before skin incision. Anesthesiologists were not masked to group assignment, but patients and obstetricians were. The primary outcome was need for additional uterotonic drugs within 24h after delivery. Analyses were by intention to treat. RESULTS: Thirty patients were assigned to each group. Additional uterotonic drugs were required in 7 (23%) patients assigned to tranexamic acid and 25 (83%) patients in the control group (P<0.001). CONCLUSION: Intravenous tranexamic acid, administered before skin incision, significantly reduced the requirement for additional uterotonics among women at increased risk for postpartum hemorrhage. Clinical Trials Registry India: CTRI/2015/05/005752.

Enhancement of α-linolenic acid content in transgenic tobacco seeds by targeting a plastidial ω-3 fatty acid desaturase (fad7) gene of Sesamum indicum to ER.

KEY MESSAGE: Expression of sesame plastidial FAD7 desaturase modified with the endoplasmic reticulum targeting and retention signals, enhances the α-linolenic acid accumulation in seeds of Nicotiana tabacum. In plants, plastidial ω-3 fatty acid desaturase-7 (FAD7) catalyzes the formation of C16 and C18 trienoic fatty acids using organellar glycerolipids and participate in the membrane lipid formation. The plastidial ω-3 desaturases (FAD7) share high sequence homology with the microsomal ω-3 desaturases (FAD3) at the amino acid level except the N-terminal organelle transit peptide. In the present study, the predicted N-terminal plastidial signal peptide of fad7 gene was replaced by the endoplasmic reticulum signal peptide and an endoplasmic reticulum retention signal was placed at the C-terminal. The expression of the modified sesame ω-3 desaturase increases the α-linolenic acid content in the range of 4.78-6.77 % in the seeds of transgenic tobacco plants with concomitant decrease in linoleic acid content. The results suggested the potential of the engineered plastidial ω-3 desaturase from sesame to influence the profile of α-linolenic acid in tobacco plant by shifting the carbon flux from linoleic acid, and thus it can be used in suitable genetic engineering strategy to increase the α-linolenic acid content in sesame and other vegetable oils.

Seed-specific increased expression of 2S albumin promoter of sesame qualifies it as a useful genetic tool for fatty acid metabolic engineering and related transgenic intervention in sesame and other oil seed crops.

The sesame 2S albumin (2Salb) promoter was evaluated for its capacity to express the reporter gusA gene encoding ß-glucuronidase in transgenic tobacco seeds relative to the soybean fad3C gene promoter element. Results revealed increased expression of gusA gene in tobacco seed tissue when driven by sesame 2S albumin promoter. Prediction based deletion analysis of both the promoter elements confirmed the necessary cis-acting regulatory elements as well as the minimal promoter element for optimal expression in each case. The results also revealed that cis-regulatory elements might have been responsible for high level expression as well as spatio-temporal regulation of the sesame 2S albumin promoter. Transgenic over-expression of a fatty acid desaturase (fad3C) gene of soybean driven by 2S albumin promoter resulted in seed-specific enhanced level of α-linolenic acid in sesame. The present study, for the first time helped to identify that the sesame 2S albumin promoter is a promising endogenous genetic element in genetic engineering approaches requiring spatio-temporal regulation of gene(s) of interest in sesame and can also be useful as a heterologous genetic element in other important oil seed crop plants in general for which seed oil is the harvested product. The study also established the feasibility of fatty acid metabolic engineering strategy undertaken to improve quality of edible seed oil in sesame using the 2S albumin promoter as regulatory element.