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Chromium (Cr) is a heavy metal that poses a grave threat to the ecosystem including plants. Chromium is very harmful to plants due to its effects on many physiological and metabolic pathways culminating in a negative impact on plant's growth, development, and ability to take up nutrients. Plants have developed physiological, biochemical, and molecular ways of defense against Cr, such as by augmenting antioxidant potential to reduce reactive oxygen species (ROS). A number of genes have been discovered to play a significant role in the defense mechanisms of plants against Cr, for example, genes associated with the activation of phytochelatins, metallothioneins, and those of enzymes like glutathione-S-transferases. Along with this, a few miRNAs have been found to be associated in alleviating Cr stress and, to augment plant tolerance by controlling transcription factors, HSPs, and the expression of a few proteins and hormones. Defense pathway genes and miRNAs have been used for the generation of transgenic phytoremediator plants. Not only do the transgenic plants have a higher tolerance to Cr, but they also act as hyperaccumulators for Cr and have the potential to remediate other heavy metals. This article describes about environmental Cr contamination, Cr effects on plants, different genes and miRNAs involved in Cr stress mitigation and use of candidate genes, microRNAs for creating transgenic plant systems for phytoremediation, and the applications of CRISPR technology. It is expected that the integration of omics approach and advanced genomics will offer scope for more effective phytoremediation of Chromium in the coming years. [Display omitted] • Chromium adversely affects plant growth, development, and nutrient uptake. • MiRNAs regulate Chromium toxicity by metal chelation, ROS signaling, and transcription factors. • GSTs, MTs, and PCs play crucial roles in Chromium detoxification and tolerance in plants. • Transgenic plants with candidate genes improve Chromium accumulation and tolerance. [ABSTRACT FROM AUTHOR]

Due to the significant challenges of growing global population and climate change, the agriculture and food industries are facing a continued demand for improving productivity. The integration of nanotechnology in food and agriculture has been envisioned to supply abundant alternative avenues for the crop improvement and food security. To meet these challenges, nanotechnology has made remarkable advancements in agricultural sciences, resulting in numerous beneficial impacts on crop yield and productivity. The key areas of nano-based agriculture aim to enhance food quality, optimized fertilizer doses, reduced agricultural inputs, and improved nutrient uptake by plants from the soil. Additionally, employing minimal hazardous agrochemicals, lowering fertilizer losses, solidification of soil and water quality, and managing nutrient supply efficiently are attributed to the advantages of nanomaterials. In future, the continued efforts and convergence of agriculture and nanotechnology offers promising benefits such as equipping plants with cutting-edge nanotools to combat abiotic (drought, salt, and temperature) and biotic (insects and diseases) stresses, precise and rapid diagnostics, and maximizing utilization of available resources. The ultimate goal in agricultural sciences is to achieve sustainable food production, which forms the backdrop for harnessing the properties of nanomaterials to enhance crop productivity and address widening growing climate challenges. In summary, the extensive applications of nanotechnology in agriculture are anticipated to support climate-smart crop cultivation. [Display omitted] • Advancement of novel nanomaterials in agriculture as nanofertilizers and nanofertilizers • Nanomaterials to stimulate soil microbial activity in cultivated crops • Nano-biosensors for climate-smart agriculture and early diagnosis of plant stress • Nano-enabled enhanced delivery systems for plant genetic engineering [ABSTRACT FROM AUTHOR]

• Optic chiasm location whether prefixed, normal or post fixed is important in pituitary surgeries. • However, optic chiasm often invaded and obscured in pituitary tumours. • Interneural angle, pituitary stalk angle aid in assessing the optic chiasm location. • Study evaluates these angles using CISS MRI sequences in essentially normal studies. • Wider interneural angle, wider pituitary stalk angle, anterior stalk indicates prefixed chiasm. Optic chiasm location is critical in sellar surgeries and may be obscured by tumor invasion. This study evaluates inter-neural angle, pituitary stalk angle, optic tract angle in prefixed, normal and post fixed optic chiasms using 3-dimensional constructive interface in steady state (CISS) sequences of magnetic resonance imaging (MRI) in essentially normal studies. MRI Brain studies of 154 patients were retrospectively evaluated. Location and height of optic chiasm was noted. Interneural angle between intracranial segments of bilateral optic nerves, pituitary stalk angle between pituitary stalk and optic chiasm, optic tract angle between optic tracts were measured and compared in prefixed, normal and post fixed chiasms using ANOVA test. Optic chiasm was prefixed in 33 (21.4%) cases, normal in 111 (72.1%) cases and postfixed in 10 (6.5%) cases with mean height of optic chiasm of 3.33 mm. There was no statistically significant difference in height and type of optic chiasm between age groups and genders. Statistically significant difference between location of optic chiasm was seen with interneural angle (p = 0.013), was highly significant with pituitary stalk angle (p < 0.001) and was not seen in optic tract angle (p = 0.455). Optic chiasm location was divided into nine groups with frequency being highest in intermediate height, normal fixed chiasms (n = 62, 40.26%) and least in post fixed high, post fixed low groups (n = 1, 0.006%). A wider interneural angle, wider pituitary stalk angle with a more anteriorly placed stalk indicates a prefixed chiasm. 3-dimensional MRI is an effective tool in assessing the optic chiasm location, when its invaded by sellar and suprasellar tumours. [ABSTRACT FROM AUTHOR]

Abstract Purpose To compare the significance of the tibio-femoral geometrical indices (notch width index, medial and lateral tibial slopes) and patellar tendon- tibial shaft angle in predicting non-contact ACL injuries and to compare these factors between genders. Methods Retrospective case control study evaluating 66 MRI knee of patients of age group of 18–60 years with 33 cases of noncontact ACL injury and 33 age matched controls. Notch width index, medial and lateral tibial slopes and patellar tendon tibial shaft angles were calculated and compared for statistical significance and was also compared between the genders. ROC curve was for plotted for the significant factors. Results Statistically significant difference was seen in notch width index and patellar tendon tibial shaft angles with cases showing a narrow notch width index and an increased patellar tendon tibial shaft angle. Gender comparative results showed no statistically significant differences. ROC curve plotted for NWI showed an optimal cut off value of 0.263 with a sensitivity of 88% and a specificity of 52%. ROC curve plotted for PTTS angle showed a cut off value of 26.7 degrees with a sensitivity of 67% and a specificity of 49%. Conclusion Narrow Notch width index and increased Patellar tendon tibial shaft angle are predictors of ACL injury. PTTS angle which has been studied as a function of knee flexion angle, can itself be an independent predictor of ACL injury (at a constant knee flexion angle). [ABSTRACT FROM AUTHOR]

Abstract: Ca2+ is an essential inorganic macronutrient, involved in regulating major physiological processes in plants. It has been well established as a second messenger and is predominantly stored in the cell wall, endoplasmic reticulum, mitochondria and vacuoles. In the cytosol, the concentration of this ion is maintained at nano-molar range. Upon requirement, Ca2+ is released from intra-cellular as well as extracellular compartments such as organelles and cell wall. In this study, we report for the first time, a whole genome transcriptome response to short (5 D) and long (14 D) term Ca2+ starvation and restoration in rice. Our results manifest that short and long term Ca2+ starvation involves a very different response in gene expression with respect to both the number and function of genes involved. A larger number of genes were up- or down-regulated after 14 D (5588 genes) than after 5 D (798 genes) of Ca2+ starvation. The functional classification of these genes indicated their connection with various metabolic pathways, ion transport, signal transduction, transcriptional regulation, and other processes related to growth and development. The results obtained here will enable to understand how changes in Ca2+ concentration or availability are interpreted into adaptive responses in plants. [Copyright &y& Elsevier]

Abstract: This study deals with establishment of hairy root cultures of Phyllanthus amarus using Agrobacterium rhizogenes and cytotoxic effects of methanolic extract of hairy roots on human adenocarcinoma cell line, MCF-7. The hairy root extract displayed a linear concentration- and time-dependent cytotoxicity. Further, increased concentration of the root extract showed an increase in the percent apoptotic cells from 26% to 36% as determined by annexin V-FITC and propidium iodide. The observed cytotoxicity correlated well with the increased levels of intracellular reactive oxygen species (ROS) as well as decreased mitochondrial membrane potential (MMP). The overall results amply suggest an appreciable antiproliferative effect of P. amarus hairy root extract on the MCF-7 cells through induction of apoptosis, thereby establishing the potential anticancer activity of the extract. Industrial relevance: Hairy roots of Phyllanthus amarus showing anti cancer properties has great potential as Industrial product. [Copyright &y& Elsevier]

Abstract: Bioregulatory molecules such as thiourea (TU) play an important role in imparting stress tolerance to crops. However, the molecular mechanism involved in the TU-mediated tolerance has not been elucidated. Towards this endeavour, the expression profile of various PIPs (plasma membrane intrinsic proteins) was studied under salt stress (NaCl; 700mM) with/without thiourea (TU; 6.5mM) at different time periods in roots of Brassica juncea. Various aquaporin isoforms demonstrated an upregulation upon salinity stress imposition, whereas they were downregulated upon TU supplementation. TU treatment also led to a decrease in the accumulation of reactive oxygen species and delimited the need for an enhanced accumulation of osmolytes. The vacuolar pH was also maintained in NaCl+TU treatment as demonstrated by in vivo 31P NMR of roots. In conclusion, TU supplementation to salt stressed seedlings was found to maintain the water homeostasis of roots through coordinated regulation of different PIP isoforms. [Copyright &y& Elsevier]

Arsenic (As) is a ubiquitous environmental carcinogen that enters the human food chain mainly through rice grains. In the present study, we evaluated the potential of thiourea (TU; non-physiological reactive oxygen species scavenger) in mitigating the negative effects of arsenic (As) stress in indica rice variety IR64, with the overall aim to reduce grain As accumulation. At seedling stage, As + TU treatment induced the formation of more numerous and longer crown roots compared with As alone. The As accumulation in main root, crown root, lower leaf and upper leaf was significantly reduced to 0.1-, 0.14-, 0.16-, 0.14-fold, respectively in As + TU treated seedlings compared with those of As alone. This reduced As accumulation was also coincided with light-dependent suppression in the expression levels of aquaporins and photosynthesis-related genes in As + TU treated roots. In addition, the foliar-supplemented TU under As-stress maintained reducing redox conditions which decreased the rate of As accumulation in flag leaves and, eventually grain As by 0.53-fold compared with those of As treatment. The agronomic feasibility of TU was validated under naturally As contaminated sites of Nadia (West Bengal, India). The tiller numbers and crop productivity (kg seed/ha) of TU-sprayed plants were increased by 1.5- and 1.18-fold, respectively; while, grain As accumulation was reduced by 0.36-fold compared with those of water-sprayed control. Thus, this study established TU application as a sustainable solution for cultivating rice in As-contaminated field conditions. [Display omitted] • Crown root formation was activated as an adaptive mechanism under arsenic stress. • Thiourea supplementation reduced arsenic accumulation from root and leaves. • Thiourea downregulated aquaporins and photosynthesis related genes in roots. • Thiourea mediated changes coincided with increased salicylic acid accumulation. • Foliar-spray of thiourea enhanced yield and reduced grain arsenic accumulation. Thiourea supplementation downregulated aquaporins to restrict arsenic accumulation in seedlings. Foliar-applied thiourea enhanced yield and reduced grain arsenic accumulation. [ABSTRACT FROM AUTHOR]

Abstract: The present study investigated arsenic (As) removal efficiency of Hydrilla verticillata from simulated As-contaminated water in field conditions. Plants (100g fresh weight) were grown in simulated contaminated water (total 8L) containing 1500μgL−1 As [in the form of arsenate (AsV)] for 45d and As accumulation and biochemical changes were analyzed at 15d intervals. As accumulation in plants increased progressively approaching 388μgg−1 dw at 45d. Considering the total dry biomass, total As removed was 8546μg (i.e. 72% of total As supplied). Despite significant As accumulation, no toxic effects were observed in terms of the level of hydrogen peroxide and lipid peroxidation, which could be attributed to the enhanced level of thiol metabolites (cysteine, glutathione) and enzymatic antioxidants (guaiacol peroxidase, catalase, ascorbate peroxidase). The study demonstrates that Hydrilla plants can find application in As remediation in field conditions. [Copyright &y& Elsevier]

The present study evaluated arsenic (As) remediation capacity of Vetiveria. zizanoides plants from artificially contaminated soil (0, 50, 100, 250, 500, 1000 mg kg−1) after various durations ie. 30, 60 and 90 d. Plants were found effective, maximum As removal being 71% after 90 d when grown in 50 mg kg−1 As. Plant growth was not affected at lower As levels (up to 250 mg kg−1) and V. zizanoides plants grown at 50 mg kg−1 have shown increase in number of tillers (43%), biomass (30%) and plant height (26%) compared to control after 90 days. Thiobarbituric acid reactive metabolites (TBARM) content has not shown any change in As exposed plants up to 30 d, maximum increase in TBARM content was found in roots and shoots of the V. zizanoides plants as 84% and 79% after 90 d when grown at 1000 mg kg−1 As contaminated plot. The activities of antioxidant enzymes, superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase and catalase were found to increase in response to As stress in a coordinated manner. Besides, various non- enzymatic antioxidants also provided defense to plants against As stress. High As accumulation and tolerance potential of V. zizanoides from artificially contaminated soil coupled with large biomass and root system, suggests its feasibility for the revegatation/remediation of As contaminated soils of West Bengal (India). • Field study showing phytoremediaion potential of V. zizanoides for arsenic from soil • V. zizanoides were exposed to various As concentrations (50 to 1000 mg kg−1) and durations (30, 60, 90 days). • V. zizanoides plants accumulated and found tolerant to As stress. • V. zizanoides plants removed 71% of As content after 90 d from 50 mg kg−1 As. • Plant's tolerance to As exposure is supported by good growth and biochemical response [ABSTRACT FROM AUTHOR]

Salt stress affects all the stages of plant growth however seed germination and early seedling growth phases are more sensitive and can be used for screening of crop germplasm. In this study, we aimed to find the most effective indicators of salt tolerance for screening ten genotypes of soybean (SL-295, Gujosoya-2, PS-1042, PK-1029, ADT-1, RKS-18, KDS-344, MAUS-47, Bragg and PK-416). The principal component analysis (PCA) resulted in the formation of three different clusters, salt sensitive (SL-295, Gujosoya-2, PS-1042 and ADT-1), salt tolerant (MAUS-47, Bragg and PK-416) and moderately tolerant/sensitive (RKS-18, PK-1029 and KDS-344) suggesting that there was considerable genetic variability for salt tolerance in the soybean genotypes. Subsequently, genotypes contrasting in salt tolerance were analyzed for their physiological traits, photosynthetic efficiency and mitochondrial respiration at seedling and early germination stages under different salt (NaCl) treatments. It was found that salt mediated increase in AOX-respiration, root and shoot K + /Na + ratio, improved leaf area and water use efficiency were the key determinants of salinity tolerance, which could modulate the net photosynthesis (carbon assimilation) and growth parameters (carbon allocation). The results suggest that these biomarkers could be can be useful for screening soybean genotypes for salt tolerance. [ABSTRACT FROM AUTHOR]

Sesuvium portulacastrum is a facultative halophyte growing in coastal salt marshes. The aim of this study was to determine growth, physiological and biochemical traits of Sesuvium portulacastrum when subjecting pot-grown plants to different concentrations of NaCl supplemented with half strength Hoagland’s nutrient solution to get the desired soil electrical conductivity (EC) of 0.3 (control), 4, 8, 12, 16, 20 dS m −1 . Enhancing salinity levels to 12 dS m −1 resulted in concomitant increase in plant height, number of shoots per plant, number of leaves per plant and leaf area. Plants grown up to EC of 12 dS m −1 exhibited higher net CO 2 assimilation rate ( P N ), transpiration rate ( E ), and water use efficiency ( WUE ). Significant increases in electrolyte leakage and lipid peroxidation were observed in plants grown at EC 16 and 20 dS m −1 . Chlorophyll a and carotenoid pigment contents were significantly increased under high salt treatment (up to EC 16 dS m −1 ) and chl a content was higher than chl b. Osmolyte accumulation as a function of osmotic adjustment and antioxidant enzyme activity (CAT, GR, SOD, APX and GPX) were maintained under salinity whereas significant Na + sequestration and Na + /K + ratio were evident with increase in salinity stress. A preliminary field experiment was conducted by using plants of S. portulacastrum grown for 90 days in control and saline soil of a field plot. The results showed that the desalination potential of the target species was reflected in the reduction of the soil electric conductivity in the salinized plots in addition to significant increases in the Na + contents in the leaves of the salinity treated plants. To summarize, our results suggest that S. portulacastrum adapts to high salinity with better growth, photosynthesis, antioxidant defense and can be used in the desalination of saline lands. [ABSTRACT FROM AUTHOR]

Abstract: Sesuvium portulacastrum (L.) L., a facultative halophyte, is considered a suitable candidate for the phytoremediation of metals. An investigation of As accumulation and tolerance was conducted in Sesuvium plants upon exposure to As(V) (100–1000μM) for 30d. Plants demonstrated a good growth even after prolonged exposure (30d) to high As(V) concentrations (1000μM) and a significant As accumulation (155μgg−1 dry weight) with a bioaccumulation factor of more than ten at each concentration. The results of shoot and root dry weight, malondialdehyde accumulation, photosynthetic pigments, and total soluble proteins demonstrated that plants did not experience significant toxicity even at 1000μM As(V) after 30d. However, metabolites (total non-protein thiols and cysteine) and enzymes (serine acetyltransferase, cysteine synthase and γ-glutamylcysteine synthetase) of thiol metabolism, in general, remained either unaffected or showed slight decline. Hence, plants tolerated high As(V) concentrations without an involvement of thiol metabolism as a major component. Taken together, the results indicate that plants are potential As accumulator and may find application in the re-vegetation of As contaminated sites. [ABSTRACT FROM AUTHOR]

Abstract: Sugarcane (Saccharum officinarum L.) juice is widely consumed by people of the tropics and subtropics. It has been used to cure jaundice and liver-related disorders in Indian systems of medicine. Its possible mechanism of action was examined in terms of antioxidant availability. The assays involved different levels of antioxidant action such as oxygen radical absorbance capacity (ORAC), radical scavenging abilities using 1,1-diphenyl-2-picryl hydrazyl (DPPH); 2,2′-azobis-3-ethyl benzthiazoline-6-sulfonic acid (ABTS); ferric reducing antioxidant power (FRAP); and protection of membranes examined by inhibition of lipid peroxidation. In addition, the content of phenols and total flavonoids were measured. The aqueous extracts of three varieties of sugarcane were studied. These varieties showed good antioxidant properties and were also able to protect against radiation induced DNA damage in pBR322 plasmid DNA and Escherishia coli cultures. In conclusion, the study reveals that the ability of sugarcane juice to scavenge free radicals, reduce iron complex and inhibit lipid peroxidation, may explain possible mechanisms by which sugarcane juice exhibits its beneficial effects in relation to its reported health benefits. [Copyright &y& Elsevier]