Metallothionein is a cysteine-rich protein with a high metal content that is widely found in nature. In addition to heavy metal detoxification, metallothionein is well known as a potent antioxidant. The high sulfhydryl content of metallothionein confers excellent antioxidant activity, enabling it to effectively scavenge free radicals and mitigate oxidative stress damage. In addition, metallothionein can play a neuroprotective role by alleviating oxidative damage in nerve cells, have an anticancer effect by enhancing the ability of normal cells to resist unfavorable conditions through its antioxidant function, and reduce inflammation by scavenging reactive oxygen species. Due to its diverse biological functions, metallothionein has a broad potential for application in alleviating environmental heavy metal pollution, predicting and diagnosing diseases, and developing skin care products and health foods. This review summarizes the recent advances in the classification, structure, biological functions, and applications of metallothionein, focusing on its powerful antioxidant effects and related functions.

To the best of the authors\' knowledge, this article is the first of its kind in Albania and neighboring countries to investigate the transformative synergistic intervention approach through cognitive behavioral therapy, parent-child interaction therapy (PCIT), and heavy metal detoxification on a child with attention-deficit/hyperactivity disorder (ADHD) and comorbid oppositional defiant disorder (ODD) and dyslexia. The limited mental health awareness in Albania, particularly regarding PCIT and similar treatments, highlights the importance of the applicability and adaptability of such interventions. This study suggests that the rapid management of comorbidities in ADHD, such as ODD and dyslexia, is better achieved by a combined intervention approach and by investigating the biological aspects. Further research with a large sample size is needed to assess the long-term sustainability and scalability of such an approach.

Heavy metals migrate easily and are difficult to degrade in the soil environment, which causes serious harm to the ecological environment and human health. Thus, soil heavy metal pollution has become one of the main environmental issues of global concern. Plant-growth-promoting rhizobacteria (PGPR) is a kind of microorganism that grows around the rhizosphere and can promote plant growth and increase crop yield. PGPR can change the bioavailability of heavy metals in the rhizosphere microenvironment, increase heavy metal uptake by phytoremediation plants, and enhance the phytoremediation efficiency of heavy-metal-contaminated soils. In recent years, the number of studies on the phytoremediation efficiency of heavy-metal-contaminated soil enhanced by PGPR has increased rapidly. This paper systematically reviews the mechanisms of PGPR that promote plant growth (including nitrogen fixation, phosphorus solubilization, potassium solubilization, iron solubilization, and plant hormone secretion) and the mechanisms of PGPR that enhance plant-heavy metal interactions (including chelation, the induction of systemic resistance, and the improvement of bioavailability). Future research on PGPR should address the challenges in heavy metal removal by PGPR-assisted phytoremediation.

Heavy metal contamination continues to be a persistent environmental problem. To address this issue, this study evaluated the impact of air nanobubbles (NBs) in water on the uptake of heavy metals by Alternanthera philoxeroides (A. philoxeroides), a common aquatic plant in China known for its rapid growth, strong vitality, and high capacity for heavy metal remediation. This study found that diluted air NBs (25% concentration) boosted cadmium uptake of A. philoxeroides by 17.39%. They also enhanced plant growth (25-50%) and photosynthetic pigments (10-20%) even at low cadmium levels (0.1 mM). Furthermore, the incorporation of 25% air NBs has been demonstrated to significantly amplify the performance of key antioxidant enzymes, such as superoxide dismutase and catalase, alongside heightened levels of crucial antioxidants such as malondialdehyde. This heightened activity of antioxidant defenses offers a compelling explanation for the potential amelioration of cadmium toxicity and concurrent enhancements in overall plant growth rates. Notably, a comprehensive analysis utilizing the excitation emission matrix-parallel factor analysis (EEM-PARAFAC) technique has revealed alterations in the composition of rhizosphere dissolved organic matter due to the presence of NBs. This ncomposition change of the rhizosphere dissolved organic mattermposition has subsequently exerted an influence on plant complexation processes and the subsequent uptake of cadmium. This study demonstrates that the strategic implementation of air NBs in water systems holds the potential to significantly enhance the plant\'s ability to detoxify cadmium and improve the uptake of heavy metals during phytoremediation processes.

From simple algal forms to the most advanced angiosperms, calcium oxalate (CaOx) crystals (CRs) occur in the majority of taxonomic groups of photosynthetic organisms. Various studies have demonstrated that this biomineralization is not a simple or random event but a genetically regulated coordination between calcium uptake, oxalate (OX) synthesis and, sometimes, environmental stresses. Certainly, the occurrence of CaOx CRs is old; however, questions related to their genesis, biosynthesis, significance and genetics exhibit robust evolution. Moreover, their speculated roles in bulk calcium regulation, heavy metal/OX detoxification, light reflectance and photosynthesis, and protection against grazing and herbivory, besides other characteristics, are gaining much interest. Thus, it is imperative to understand their synthesis and regulation in relation to the ascribed key functions to reconstruct future perspectives in harnessing their potential to achieve nutritious and pest-resistant crops amid anticipated global climatic perturbations. This review critically addresses the basic and evolving concepts of the origin (and recycling), synthesis, significance, regulation and fate vis-à-vis various functional aspects of CaOx CRs in plants (and soil). Overall, insights and conceptual future directions present them as potential biominerals to address future climate-driven issues.

All organisms, fundamentally, are made from the same raw material, namely the elements of the periodic table. Biochemical diversity is achieved by how these elements are utilized, for what purpose, and in which physical location. Determining elemental distributions, especially those of trace elements that facilitate metabolism as cofactors in the active centers of essential enzymes, can determine the state of metabolism, the nutritional status, or the developmental stage of an organism. Photosynthetic eukaryotes, especially algae, are excellent subjects for quantitative analysis of elemental distribution. These microbes utilize unique metabolic pathways that require various trace nutrients at their core to enable their operation. Photosynthetic microbes also have important environmental roles as primary producers in habitats with limited nutrient supplies or toxin contaminations. Accordingly, photosynthetic eukaryotes are of great interest for biotechnological exploitation, carbon sequestration, and bioremediation, with many of the applications involving various trace elements and consequently affecting their quota and intracellular distribution. A number of diverse applications were developed for elemental imaging, allowing subcellular resolution, with X-ray fluorescence microscopy (XFM, XRF) being at the forefront, enabling quantitative descriptions of intact cells in a non-destructive method. This Tutorial Review summarizes the workflow of a quantitative, single-cell elemental distribution analysis of a eukaryotic alga using XFM.

Aleurolyphus ovatus Troupeau is one of the most predominant species of the Acaridae family worldwide. Recent reports have demonstrated that the accumulation of lead in stored grains and dietary items exceeds the required standards. However, the molecular mechanism of heavy metal stress on mites has not been reported. To understand the mechanism underlying the heavy metal response of A. ovatus, comparative transcriptome analysis was performed in this study using an Illumina high throughput mRNA sequencing (RNA-seq) platform. A. ovatus was fed on artificial diets containing two different concentrations of lead, namely, a low concentration of 12.5 mg/kg (LAO) and a high concentration of 100 mg/kg (HAO), while the mites in the control (NAO) group were not exposed to lead. A total of 44,362 unigenes, with an average length of 1547 bp, were identified. Of these, 996 unigenes were successfully annotated in seven functional databases. The number of differentially expressed genes (DEGs) in A. ovatus under different lead concentrations was compared. In NAO versus LAO group, including 310 up-regulated and 1580 down-regulated DEGs. In NAO versus HAO group, including 3928 up-regulated and 1761 down-regulated DEGs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment indicated that detoxification enzyme genes were significantly expressed in pathways, such as cytochrome P450 foreign body metabolism, glutathione metabolism and drug metabolism-cytochrome pathway. The results of gene annotation and quantitative real-time PCR showed that high concentration of lead significantly stimulated the expression of metabolic detoxification enzyme genes such as glutathione S transferase (GST) and superoxide dismutase (SOD), while low concentration inhibited their expression. This study will provide a basis for the molecular mechanism of A. ovatus in response to heavy metal lead stimulation in stored grain.

Calcium oxalate (CaOx) crystals in plants act as a sink for excess Ca and play an essential role in detoxifying heavy metals (HMs). However, the mechanism and related influencing factors remain unclear. Amaranth (Amaranthus tricolor L.) is a common edible vegetable rich in CaOx and a potential Cd hyperaccumulation species. In this study, the hydroponic experiment was carried out to investigate the effect of exogenous Ca concentrations on Cd uptake by amaranth. The results showed that either insufficient or excess Ca supply inhibited amaranth growth, while the Cd bioconcentration factor (BCF) increased with Ca concentration. Meanwhile, the sequence extraction results demonstrated that Cd mainly accumulated as pectate and protein-bound species (NaCl extracted) in the root and stem, compared to pectate, protein, and phosphate-bound (acetic acid extractable) species in the leaf. Correlation analysis showed that the concentration of exogenous Ca was positively correlated with amaranth-produced CaOx crystals but negatively correlated with insoluble oxalate-bound Cd in the leaf. However, since the accumulated insoluble oxalate-bound Cd was relatively low, Cd detoxification via the CaOx pathway in amaranth is limited.

This study researched microbial community succession in response to sludge composting efficiency and heavy metal detoxification during municipal sludge co-composting with spent mushroom and spent bleaching. The change law of key physicochemical properties, the heavy metals contents and forms during composting were analyzed, and the passivation of heavy metals after composting was explored. High-throughput sequencing was used to analyze the microbial community structure of treat 2 during composting, and the correlation analysis of microbial community structure with heavy metal contents and forms were carried out. The results showed that the sludge of each treatment reached composting maturity after 26 days of composting. Organic matter content, electrical conductivity, pH and seed germination index of treat 2 were all in line with the standard limit of agricultural sludge. Because of the presence of compost bacteria addition, the passivating heavy metals performance of treat 2 satisfied the standard limit of agricultural sludge after composting, which was superior to that of treat 1 and treat 3. The diversity of microbial communities in treat 2 decreased during composting. Extensive bacteria such as Bacillus, Geobacter, Lactobacillus, and Pseudomonas, which possessed the abilities of heavy metal passivation and organic oxidizing, were dominant in treat 2 during the heating stage. However, as composting proceeded, Tuberibacillus with ability of organic oxidizing gradually became the most dominant species at the thermophilic and cooling stages. Changes in microbial function varied from changes of microbial community in treat 2, subsequently affected the performances of heavy metal passivation and organic oxidizing during composting.

Nanorobots hold great promise for integrated drug delivery systems that are responsive to molecular triggers. Herein, we successfully developed an automatic smart bionanorobot that has transport capability and recognizes and removes zinc ions from poisoned cells based on nanoscale polyhedral oligomeric silsesquioxane molecules. This intelligent bionanorobot can easily move inside and outside the cell and find zinc ions owing to its highly selective recognition to zinc ions and high cell permeability, especially the well-combined high penetration and strong binding energy. More importantly, it was also found that this intelligent bionanorobot can restore round HeLa cells to a normal fusiform cell morphology following high-concentration zinc treatment and does not interfere with cell proliferation and division. It was also shown by in vivo experiments that the bionanorobot can inhibit persistent enlargement of the liver caused by zinc ion poisoning.