Search Results (3,558)

This study introduces a novel approach for transforming the cationic surfactant, cetyltrimethylammonium bromide (CTAB), into fluorescent carbon dots (CDs) capable of detecting cadmium ions at ultralow concentrations. The current approach involves preparing CDs through hydrothermal process at various pH levels. The CDs synthesized using pH 10, CTAB-CDs-10, exhibited the highest fluorescence quantum yield (QY), 14.22%. UV-Vis spectroscopy helped identify specific peaks between 210 and 300 nm, corresponding to the π–π* transitions of the aromatic C=C bonds. Transmission electron microscopic (TEM) analysis verified the uniform spherical morphology with a particle size < 2.45 nm. FT-IR analysis confirmed the presence of C=C stretching vibrations. The Box–Behnken (BB) Design was used to reconnoiter the influence of three variables on the response parameter: the F₀/F ratio. The best performance could be achieved at a pH of 9, after only 300 s, and a temperature of 50 °C. The developed CTAB-CDs-based nanoprobe showed an ON–OFF behavior when came in contact with cadmium (II) and demonstrated high sensitivity with a limit of detection as low as 0.06 µM (0.007 ppm) over a wide linear range of 2–103 µM. Validation tests confirmed the applicability of the CTAB-CDs-based nanoprobe for detecting cadmium (II) in tap and drinking waters with high accuracy and precision. Full article

Cadmium is a contributing factor to cardiovascular diseases and highly toxic to vascular endothelial cells. It has a distinct mode of injury, causing the de-endothelialization of regions in the monolayer structure of endothelial cells in a concentration-dependent manner. However, the specific molecules involved in the cadmium toxicity of endothelial cells remain unclear. The purpose of this study was to identify the specific molecular mechanisms through which cadmium affects endothelial detachment. Cadmium inhibited the expression of claudin-5 and zonula occludens (ZO)-1, which are components of tight junctions (strongest contributors to intercellular adhesion), in a concentration- and time-dependent manner. Compared to arsenite, zinc, and manganese, only cadmium suppressed the expression of both claudin-5 and ZO-1 molecules. Moreover, the knockdown of claudin-5 and ZO-1 exacerbated cadmium-induced endothelial cell injury and expansion of the detachment area, whereas their overexpression reversed these effects. CRE-binding protein inhibition reduced cadmium toxicity, suggesting that CRE-binding protein activation is involved in the cadmium-induced inhibition of claudin-5 and ZO-1 expression and endothelial detachment. These findings provide new insights into the toxicological mechanisms of cadmium-induced endothelial injury and risk of cardiovascular disease. Full article

The aim of this study was to explore the feasible measurement of the control of cadmium (Cd) and arsenic (As) accumulation in rice grains. A field experiment was carried out to research the effect of different treatments, including spraying silicon (Si)/selenium (Se) foliar fertilizers, the application of lime (CaO), water management (continuous flooding), and the co-application of foliar fertilizers and flooding, on Cd and As accumulation in rice grains in Guangxi Province. The results indicate that Cd accumulation in rice grains decreased under different treatments and Cd content in rice grains reached the threshold of 0.2 mg kg⁻¹. In the single technical treatments, CaO application, flooding, spraying foliar Se fertilizer, and spraying foliar Si fertilizer decreased Cd content by 73.15%, 60.44%, 45.76%, and 36.07%, respectively. However, flooding and CaO amendment enhanced As accumulation in rice grains. The co-application of flooding and spraying foliar fertilizer can simultaneously reduce Cd and As in rice grains. In addition, they resulted in lower Cd content than the single technical treatments. Among the treatments, the lowest bioaccumulation factors of Cd and As were found after the co-application of flooding and Si foliar fertilizer, which decreased these factors by 74.02% and 22.72%, respectively. These results suggest that spraying foliar Si fertilizer combined with flooding may be a promising method to synchronously inhibit the accumulation of Cd and As in rice. Full article

Identifying key genes involved in Cadmium (Cd) response pathways in plants and developing low-Cd-accumulating cultivars may be the most effective and eco-friendly strategy to tackle the problem of Cd pollution in crops. In our previous study, Stressseventy subfamily A 4 (SSA4) was identified to be associated with Cd tolerance in yeast. Here, we investigated the mechanism of SSA4 in regulating Cd tolerance in yeast. ScSSA4 binds to POre Membrane 34 (POM34), a key component of nuclear pore complex (NPC), and translocates from the cytoplasm to the nucleus, where it regulates the expression of its downstream gene, Viable in a Hal3 Sit4 background 1 (VHS1), resulting in reduced Cd accumulation in yeast cells. Additionally, we identified a Chinese cabbage SSA4 gene, BrSSA4c, which could enhance the Cd tolerance in Chinese cabbage. This study offers new insights into the regulatory mechanisms of Cd tolerance in yeast, a model organism, and paves the way for the genetic enhancement of Cd tolerance in Chinese cabbage. Full article

Peanut (Arachis hypogaea L.) is one of the most important oil and food legume crops worldwide. ASR (abscisic acid, stress, ripening) plays extremely important roles in plant growth and development, fruit ripening, pollen development, and stress. Here, six ASR genes were identified in peanut. Structural and conserved motif analyses were performed to identify common ABA/WDS structural domains. The vast majority of ASR genes encoded acidic proteins, all of which are hydrophilic proteins and localized on mitochondria and nucleus, respectively. The cis-element analysis revealed that some cis-regulatory elements were related to peanut growth and development, hormone, and stress response. Under normal growth conditions, AhASR4 and AhASR5 were expressed in all tissues of peanut plants. Quantitative real-time PCR (qRT-PCR) results indicated that peanut ASR genes exhibited complex expression patterns in response to abiotic stress. Notably, under drought and cadmium (Cd) stress, the expression levels of AhASR4 and AhASR5 were significantly upregulated, suggesting that these genes may play a crucial role in the peanut plant’s resistance to such stressors. These results provide a theoretical basis for studying the evolution, expression, and function of the peanut ASR gene family and will provide valuable information in the identification and screening of genes for peanut stress tolerance breeding. Full article

This study aimed to evaluate the presence of various elements in edible insect-based food products available for human consumption. Several products were analyzed using atomic spectroscopy, and descriptive statistical analysis was conducted with IBM SPSS Statistics 27. The results revealed the presence of elements such as arsenic, cadmium, copper, magnesium, nickel, silver, lead, tungsten, uranium, mercury, platinum, aluminum, beryllium, bismuth, lithium, antimony, and thallium. Significant differences were found based on product type, insect species, and country of origin. The findings underscore the need to assess each insect species for its potential as a food source, taking into account element bioaccumulation factors. A comprehensive, global approach is essential for ensuring the food safety of edible insects as a sustainable protein source. Further research is needed to address these safety concerns. Full article

Exogenous DNA damage represents one of the most harmful outcomes produced by environmental, physical, or chemical agents. Here, a comparative analysis of DNA fragmentation was carried out on Paracentrotus lividus sea urchin embryos exposed to four common pollutants of the marine environment: vanadium, cadmium, gadolinium and selenium. Using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, fragmented DNA was quantified and localized in apoptotic cells mapping whole-mount embryos. This is the first study reporting how different chemicals are able to activate distinctive apoptotic features in sea urchin embryos, categorized as follows: (i) cell-selective apoptosis, showing DNA fragmentation restricted to a subset of extremely damaged cells, acting as an embryo survival mechanism; or (ii) total apoptosis, with fragmented DNA widespread throughout the cells of the entire embryo, leading to its death. Also, this is the first report of the effects of Se exposure on P. lividus sea urchin embryos. These data confirm the TUNEL assay as the most suitable test to study DNA fragmentation in the sea urchin embryo model system. Taken together, this research highlights embryos’ ability to find alternative pathways and set physiological limits for development under stress conditions. Full article

Water pollution is a pressing global issue significantly affecting ecosystem health, biodiversity, and human well-being. While numerous studies have concentrated on toxic metals like cadmium, lead, and mercury, essential metals such as copper and zinc often receive less attention. This review focuses on the distribution and occurrence of copper and zinc in surface water, their accumulation in freshwater organisms, and potential strategies for mitigating the environmental pressure caused by these metals. Zinc concentrations in uncontaminated freshwater usually range from 3 to 12 μg∙L⁻¹ and form low-bioavailable hydroxo-complexes that are especially stable in weak alkaline water. The zinc concentration trend globally is Europe > Africa > Asia > South America > North America. Conversely, copper concentrations vary from 0.2 to 5.5 µg∙L⁼¹, with the order being Asia > Africa > South America > North America > Europe. Humic substances are the likely predominant ligands for copper in these environments. The accumulation of copper and especially zinc in freshwater animals may not be a reliable indicator of metal pollution due to potential metabolic regulation. Bioremediation approaches, including phytoremediation and biosorption using plants and microorganisms, show promise in addressing water contamination. Future research should emphasize advanced bioremediation methods, emission reduction strategies, and refined modeling techniques to predict pollution trends and evaluate remediation effectiveness. Full article

Maternal cadmium exposure during pregnancy has been demonstrated to have detrimental effects on offspring development. However, the impact of maternal cadmium exposure on offspring oocytes remains largely unknown, and the underlying mechanisms are not fully understood. In this study, we found that maternal cadmium exposure during pregnancy resulted in selective alteration in epigenetic modifications of mouse oocytes in offspring, including a decrease in H3K4me2 and H4K12ac, as well as an increase in DNA methylation of H19. Although ROS levels and mitochondrial activity remain at normal levels, the DNA damage marker γH2AX was significantly increased and the DNA repair marker DNA-PKcs was remarkably decreased in offspring oocytes from maternal cadmium exposure. These alterations are responsible for the decrease in the quality of mouse oocytes in offspring induced by maternal cadmium exposure. As a result, the meiotic maturation of oocytes and subsequent early embryonic development are influenced by maternal cadmium exposure. RNA-seq results showed that maternal cadmium exposure elicits modifications in the expression of genes associated with metabolism, signal transduction, and endocrine regulation in offspring ovaries, which also contribute to the disorders of oocyte maturation and failures in early embryonic development. Our research provides direct evidence of transgenerational epigenetic inheritance of cadmium reproductive toxicity in mouse germ cells. Full article

The contamination of soil with the heavy metal cadmium (Cd) is increasingly prominent and severely threatens food security in China. Owing to its low cost, suitable efficacy, and ability to address the shortcomings of plant remediation by enhancing the ability of plants to take up Cd, plant–microbe combination remediation technology has become a research hotspot in heavy metal pollution remediation. A pot experiment was performed to examine the effects of inoculation with the plant-growth-promoting bacterium Brevibacillus sp. SR-9 on the biomass, Cd accumulation, and soil nutrients of hybrid Pennisetum. The purpose of this study was to determine how Brevibacillus sp. SR-9 alleviates stress caused by heavy metal contamination. High-throughput sequencing and metabolomics were used to determine the effects of inoculation on the soil bacterial community composition and microbial metabolic functions associated with hybrid Pennisetum. The results suggest that mutation of Brevibacillus sp. SR-9 effectively alleviates Cd pollution stress, leading to increased biomass and accumulation of Cd in hybrid Pennisetum. The aboveground biomass and the root weight increased by 12.08% and 27.03%, respectively. Additionally, the accumulation of Cd in the aboveground sections and roots increased by 21.16% and 15.50%, respectively. Measurements of the physicochemical properties of the soil revealed that the strain Brevibacillus sp. SR-9 slightly increased the levels of available phosphorus, total nitrogen, total phosphorus, and available potassium. High-throughput DNA sequencing revealed that Brevibacillus sp. SR-9 implantation modified the composition of the soil bacterial community by increasing the average number of Actinobacteria and Bacillus. The total nitrogen content of the soil was positively correlated with the Actinobacteria abundance, total phosphorus level, and available phosphorus level. Metabolomic analysis revealed that inoculation affected the abundance of soil metabolites, and 59 differentially abundant metabolites were identified (p < 0.05). Among these, 14 metabolites presented increased abundance, whereas 45 metabolites presented decreased abundance. Fourteen metabolic pathways were enriched in these metabolites: the folate resistance pathway, the ABC transporter pathway, D-glutamine and D-glutamic acid metabolism, purine metabolism, and pyrimidine metabolism. The abundance of the metabolites was positively correlated with the levels of available phosphorus, total potassium, total phosphorus, and total nitrogen. According to correlation analyses, the development of hybrid Pennisetum and the accumulation of Cd are strongly associated with differentially abundant metabolites, which also impact the abundance of certain bacterial populations. This work revealed that by altering the makeup of microbial communities and their metabolic processes, bacteria that promote plant development can mitigate the stress caused by Cd. These findings reveal the microbiological mechanisms through which these bacteria increase the ability of hybrid Pennisetum to take up the Cd present in contaminated soils. Full article

Heavy metals in soil can inflict direct damage on plants growing within it, adversely affecting their growth height, root development, leaf area, and other physiological traits. To counteract the toxic impacts of heavy metals on plant growth and development, plants mitigate heavy metal stress through mechanisms such as metal chelation, vacuolar compartmentalization, regulation of transporters, and enhancement of antioxidant functions. WRKY transcription factors (TFs) play a crucial role in plant growth and development as well as in responses to both biotic and abiotic stresses; notably, heavy metal stress is classified as an abiotic stressor. An increasing number of studies have highlighted the significant role of WRKY proteins in regulating heavy metal stress across various levels. Upon the entry of heavy metal ions into plant root cells, the production of reactive oxygen species (ROS) is triggered, leading to the phosphorylation and activation of WRKY TFs through MAPK cascade signaling. Activated WRKY TFs then modulate various physiological processes by upregulating or downregulating the expression of downstream genes to confer heavy metal tolerance to plants. This review provides an overview of the research advancements regarding WRKY TFs in regulating heavy metal ion stress—including cadmium (Cd), arsenic (As), copper (Cu)—and aluminum (Al) toxicity. Full article

Since even low-level environmental exposure to cadmium (Cd) can lead to numerous unfavourable health outcomes, including damage to the nervous system, it is important to recognize the risk of health damage by this xenobiotic, the mechanisms of its toxic influence, and to find an effective protective strategy. This study aimed to evaluate, in a female Wistar rat model of current human environmental exposure to Cd (1 and 5 mg/kg of diet for 3–24 months), if the low-to-moderate treatment with this element can harm the brain and whether the supplementation with a 0.1% Aronia melanocarpa L. (Michx.) Elliott berries (chokeberries) extract (AE) can protect against this effect. The exposure to Cd modified the values of various biomarkers of neurotoxicity, including enzymes (acetylcholinesterase (AChE), sodium-potassium adenosine triphosphatase (Na⁺/K⁺-ATPase), phospholipase A2 (PLA2), and nitric oxide synthase 1 (NOS1)) and non-enzymatic proteins (calmodulin (CAM), nuclear factor erythroid 2-related factor 2 (Nrf2), and Kelch-like ECH-associated protein 1 (KEAP1)) crucial for the functioning of the nervous system, as well as the concentrations of calcium (Ca) and magnesium (Mg) and some metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in the brain tissue. The co-administration of AE, partially or entirely, protected from most of the Cd-induced changes alleviating its neurotoxic influence. In conclusion, even low-level chronic exposure to Cd may adversely affect the nervous system, whereas the supplementation with A. melanocarpa berries products during the treatment seems a protective strategy. Full article

Quantum dot light-emitting diodes (QLEDs) have potential application prospects in new-type display fields due to their wide color gamut, high energy efficiency, as well as low-cost mass production. Research on lead-free and cadmium-free blue quantum dots (QDs) is urgently needed for the development of QLED technology. For I-III-VI QDs, multiple luminescent centers generated by imbalanced local charge distribution have a detrimental effect on the emission performance. Regulating the chemical composition is one of the effective methods to control the defect type of blue-emitting QDs. In this work, narrow-bandwidth (with a full width at half maximum of 53 nm) blue CuAlSe₂ QDs are achieved by altering the Cu/Al ratio. As the Cu/Al ratio increases from 0.2 to 1, the photoluminescence (PL) emission peak is red-shifted from 450 to 460 nm, with PL quantum yield up to 56%. The PL spectra are deconvoluted into three emission peaks by Gaussian fitting analysis, demonstrating the main luminescent contribution coming from the radiative recombination of electrons residing in the aluminum–copper antisite (Al_Cu) defect level with the holes in the valence band. This work provides a new approach for preparing eco-friendly and high-efficient blue-emitting QDs. Full article

The practise of geophagy is common amongst women of childbearing age from different geographic locations, including South Africa, regardless of their social and economic status such as their level of education, race, marital status, income or occupation. This study aimed to examine the women of childbearing age in Tshwane District, Gauteng Province, South Africa. An experimental study was conducted at the laboratory to examine the chemical composition of clay soil ingested by geophagic women of childbearing age. Thirty-nine clay soil samples were collected from study participants attending antenatal care services and family planning at public healthcare facilities of Tshwane District, Gauteng Province, and subjected to geochemical analysis. The concentrations of vanadium, manganese, chromium, and barium were detected in quantities exceeding 100 mg/kg in almost all samples. Cadmium, mercury and silver were detected in low concentrations below 1 mg/kg in all samples. The practice of geophagy amongst women of childbearing age has been reported to be associated with detrimental health outcomes and risks such as iron deficiency anaemia, constipation, shortness of breath, maternal and childhood mortalities and morbidities, neurological and central nervous system disorder, death, appendicitis, cancers, teratogenic risks, and ulcers. The chemical composition of clay soil eaten by geophagic women of childbearing age contains potentially harmful substances, thus the practise of geophagy is toxic and should be discouraged to protect public health. Full article

The plant vacuole is a very dynamic organelle that can occupy more than 90% of the cell volume and is essential to plant cell growth and development, the processes in which auxin (indole-3-acetic acid, IAA) is a central player. It was found that when IAA or FC (fusicoccin) was present in the control medium of vacuoles isolated from red beet taproots at a final concentration of 1 µM, it increased their volume to a level that was 26% or 36% higher than that observed in the control medium without growth regulators, respectively. In the presence of IAA and FC, the time after which most vacuoles ruptured was about 10 min longer for IAA than for FC. However, when cadmium (Cd) or lead (Pb) was present in the control medium at a final concentration of 100 µM, it increased the volume of the vacuoles by about 26% or 80% compared to the control, respectively. The time after which the vacuoles ruptured was similar for both metals. The combined effect of IAA and Pb on the volume of the vacuoles was comparable with that observed in the presence of Pb only, while for FC combined with Pb, it was additive. The use of IAA or FC together with Cd caused in both cases a decrease in the vacuole volumes by about 50%. The data presented in this study are discussed, taking into account the structure and function of the vacuolar membrane (tonoplast) and their changes in the presence of growth substances, heavy metals, and their combination. Full article