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The fabricated metal product industries were identified as producers of variable and heterogeneous pollution. Workers in these manufacturing facilities are exposed to multiple pollutants present at variable concentrations. Specific known adverse health effects include bladder cancer associated with metalworking fluid exposure and lung cancer associated with electroplating processes. To reduce the incidence of these adverse effects, the main challenge is to identify the most hazardous pollutants within this complex exposure environment and evaluate the corresponding health potentials. In this study, exposure indices were formulated to assess multiple metal exposures with the ultimate goal of providing relevant information for exposure reduction and control measures. Fifteen plants, including metal mold manufacturing, metal casting, and surface treatment plants, were investigated in terms of total concentration, summation of corresponding ratio to threshold limit value (STLVr), hazard index (HI), and incremental cancer risk. The results revealed that emissions of aluminum, iron, and manganese were primarily found in the metal mold manufacturing/casting plants, while emissions of chromium, nickel, and zinc were found in surface treatment plants. STLVr and HI were more useful than the total concentration for identifying hazardous metals, which were chromium and nickel, and could specify the facilities that were in need of control measures. As for cancer risk, the metal mold manufacturing/casting plants had lower risk than the surface treatment plants, and the contributing metals for these two plant types were cobalt and chromium, respectively. This study established a useful procedure to evaluate health hazards and cancer risk. The resulting information is useful for prioritizing mitigation control of multiple metal exposures. [ABSTRACT FROM AUTHOR]

Total hip arthroplasty (THA) is a successful orthopaedic surgical procedure, and its longevity depends on bearing components and implant fixation. Optimizing polyethylene and ceramics has led to improved wear parameters and contributed to improved long-term outcomes. The present systematic review investigated whether time span from implantation, patient characteristics and performance status exert an influence on liner wear and head migration in THA. This study was conducted in conformity to the 2020 PRISMA guidelines. All the clinical investigations which reported quantitative data on the amount of liner wear and head migration in THA were considered. Only studies which reported quantitative data at least on one of the following patient characteristics were suitable: mean age, mean BMI (kg/m2), sex, side, time span between the index THA and the last follow-up (months) were eligible. A multiple linear model regression analysis was employed to verify the association between patient characteristics and the amount of liner wear and/or head migration. The Pearson Product-Moment Correlation Coefficient was used to assess the association between variables. Data from 12,629 patients were considered. The mean length of the follow-up was 90.5 ± 50.9 months. The mean age of patients at surgery was 58.4 ± 9.4 years, and the mean BMI was 27.2 ± 2.5 kg/m2. 57% (7199 of 12,629 patients) were women, and in 44% (5557 of 12,629 patients) THAs were performed on the left. The mean pre-operative Harris hip score was 46.5 ± 6.0 points. There was evidence of a moderate positive association between the amount of liner wear and the time elapsed between the index surgery to the follow-up (P = 0.02). There was evidence of a moderate positive association between the amount of head migration and the time elapsed between the index surgery to the follow-up (P = 0.01). No further statistically significant association was found. The time elapsed between the index surgery to the follow-up was the most important factor which influence the head migration and liner wear in THA. Patients' characteristics and preoperative physical activity did not influence the amount of head migration and liner wear. [ABSTRACT FROM AUTHOR]

Differences in the health risk values calculated for consumers of potentially harmful elements (PHEs) present in edible plants were investigated. Based on a comprehensive literature search, the highest PHE contents in plants were identified in the southern and western regions of Poland, that also revealed the highest geochemical enrichment with Zn, Pb, Cu, As, Cd, and Tl. The highest unacceptable non-carcinogenic risk (HQ) values for mean PHE contents in Poland were found for Pb: toddlers (2.80), pre-schoolers (1.80), and school-aged children (1.45) and for Cd for toddlers (1.42). The highest unacceptable carcinogenic risk (CR) values for mean As content was observed for adults (5.9 × 10–5). The highest non-carcinogenic risk values for consumers were reported in Silesia, Lower Silesia, Lublin, Lesser Poland, and Opole Provinces, indicating the impact of geochemical variability on risk values. [ABSTRACT FROM AUTHOR]

The present systematic review investigated the concentration of chromium (Cr) and cobalt (Co) in serum in patients who have undergone total hip arthroplasty (THA). The first outcome of interest was to investigate the mean concentration in serum of Cr and Co using different material combinations and to verify whether their concentrations change significantly using different patterns of head and liner in THA. The second outcome of interest was to investigate whether the time elapsed from the index surgery to the follow-up, BMI, sex, and side exert an influence on the mean concentration of Cr and Co in serum in patients who have undergone THA. The following material combinations were investigated (head-liner): Ceramic-Co Cr (CoCr), CoCr-CoCr, CoCr-Polyethylene, CoCr high carbide-CoCr high carbide. Data from 2756 procedures were retrieved. The mean length of follow-up was 69.3 ± 47.7 months. The ANOVA test evidenced good comparability in age, length of follow-up, BMI, and sex (P > 0.1). In patients who have undergone THA, the mean concentration in the serum of Co ranged between 0.5 µg/L and 3.5 µg/L, and the mean concentration of Cr from 0.6 to 2.6 µg/L. The difference in the concentration of Co and Cr in serum is strictly related to the implant configuration, with the coupling CoCr-CoCr showing the highest and CoCr-Polyethylene showing the lowest concentration. Patient characteristics, BMI, sex, side and the time elapsed from the index surgery to the last follow-up did not exert a significant influence on the concentration of Co and Cr in serum in patients who have undergone total hip arthroplasty (THA). [ABSTRACT FROM AUTHOR]

This study aims to study the solubility of acid gas, i.e., hydrogen sulfide (H2S) in different solvents. Three intelligent approaches, including Multilayer Perceptron (MLP), Gaussian Process Regression (GPR) and Radial Basis Function (RBF) were used to construct reliable models based on an extensive databank comprising 5148 measured samples from 54 published sources. The analyzed data cover 95 single and multicomponent solvents such as amines, ionic liquids, electrolytes, organics, etc., in broad pressure and temperature ranges. The proposed models require just three simple input variables, i.e., pressure, temperature and the equivalent molecular weight of solvent to determine the solubility. A competitive examination of the novel models implied that the GPR-based one gives the most appropriate estimations with excellent AARE, R2 and RRMSE values of 4.73%, 99.75% and 4.83%, respectively for the tested data. The mentioned intelligent model also performed well in describing the physical behaviors of H2S solubility at various operating conditions. Furthermore, analyzing the William's plot for the GPR-based model affirmed the high reliability of the analyzed databank, as the outlying data points comprise just 2.04% of entire data. In contrast to the literature models, the newly presented approaches proved to be applicable for different types of single and multicomponent H2S absorbers with AAREs less than 7%. Eventually, a sensitivity analysis based on the GPR model reflected the fact that the solvent equivalent molecular weight is the most influential factor in controlling H2S solubility. [ABSTRACT FROM AUTHOR]

East Kolkata Wetlands (EKW) is an important site for fish culture in sewage-fed areas, which are major receivers of pollutants and wastages from Kolkata. EKW is internationally important as the Ramsar site was declared on Aug 2002 with an area of 125 km2. EKW is a natural water body where wastewater-fed natural aquaculture has been practiced for more than 70 years. It is ecologically vulnerable due to the discharge of toxic waste through sewage canals from cities. Assessing the EKW to understand the inflow and load of the toxic metal (s) in fish, water, and sediments samples is essential. The field (samples collection from 13 sites) and lab (determination of toxic level of metals) based research were carried out to assess metal toxicity and health risk assessment in EKW. The levels of eighteen metals (18), namely Chromium, Vanadium, Cobalt, Manganese, Copper, Nickel, Zinc, Silver, Molybdenum, Arsenic, Selenium, Tin, Gallium, Germanium, Strontium, Cadmium, Mercury, and Lead, were determined using Inductively coupled plasma mass spectrometry (ICP-MS) in five fish tissues viz. muscle, liver, kidney, gill and brain, along with the water samples and soil sediments in 13 sampling sites. The bioaccumulation and concentration of metals in fish tissues, soil sediments, and water samples were well within the safe level concerning the recommendation of different national and international agencies except for a few metals in a few sampling sites like Cd, As, and Pb. The geoaccumulation index (Igeo) was also determined in the soil sediments, indicating moderate arsenic, selenium, and mercury contamination in a few sites. The contamination index in water was also determined in 13 sampling sites. The estimated daily intake (EDI), reference dose (RfD), target hazard quotient (THQ), slope factor and cancer risk of Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd, Pb and Hg from fish muscle were determined. Based on the results of the present investigation, it is concluded that fish consumption in the East Kolkata Wetland (EKW) is safe. The effects of bioaccumulation of metals in muscle tissue were well within the safe level for consumption as recommended by WHO/FAO. [ABSTRACT FROM AUTHOR]

In this study, the multiple toxic effects of potassium bromate were investigated in Allium cepa L., an indicator test material. In addition, the toxicity-reducing effects of grape seed extract (GSE) were tested. The toxicity was investigated by some physiological (germination percentage, root length, weight gain, relative injury rate), cytogenetic [mitotic index (MI), micronucleus (MN), and chromosomal abnormalities (CAs)], biochemical [malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) levels] and anatomical parameters. A. cepa bulbs were divided into 6 groups as control and five treatment groups (Group II: 465 mg/L GSE, Group III: 930 mg/L GSE, Group IV: 100 mg/L potassium bromate, Group V: 100 mg/L potassium bromate + 465 mg/L GSE, Group VI: 100 mg /L potassium bromate + 930 mg/L GSE). The bulbs were germinated for 72 h and at the end of the period the bulbs were subjected to routine preparations and made ready for analysis and measurements. As a result, potassium bromate exposure caused statistically significant (p < 0.05) decreases in all physiological parameter values. Potassium bromate application decreased MI by 41.6%, and increased the MN and CAs frequencies. CAs such as fragment, sticky chromosome, and vagrant chromosome, unequal distribution of chromatin, reverse polarization, nuclear bud and disordered mitosis were induced in root meristem cells. The mechanism of potassium bromate genotoxicity has been associated with DNA-potassium bromate interaction supported by spectral shift. Potassium bromate caused a decrease in GSH levels and an increase in MDA, SOD and CAT levels, thereby disrupting the antioxidant/oxidant balance in root tip cells. GSE administration in two different doses together with potassium bromate reduced the toxic effects and caused improvements in all parameters examined. The most significant reduction in toxicity was in group VI, which received 930 mg/L GSE, and there was an improvement about 18% in MI levels and an improvement about 44% in GSH levels in this group. While GSE application increased physiological parameters and GSH levels, it decreased MDA, SOD, CAT levels, MN and CAs frequencies. As a result, it has been determined that potassium bromate causes multi-directional toxicity at high doses and A. cepa is a very reliable indicator in determining this toxicity. In addition, GSE extract has been found to have a strong role in reducing the toxicity induced by potassium bromate. [ABSTRACT FROM AUTHOR]

In the present work, different nanoparticles spinel ferrite series (MFe2O4, Co0.5M0.5Fe2O4; M = Co, Mn, Ni, Mg, Cu, or Zn) have been obtained via sonochemical approach. Then, sol–gel method was employed to design core–shell magnetoelectric nanocomposites by coating these nanoparticles with BaTiO3 (BTO). The structure and morphology of the prepared samples were examined by X-ray powder diffraction (XRD), scanning electron microscope (SEM) coupled with energy dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscope (HR-TEM), and zeta potential. XRD analysis showed the presence of spinel ferrite and BTO phases without any trace of a secondary phase. Both phases crystallized in the cubic structure. SEM micrographs illustrated an agglomeration of spherical grains with nonuniformly diphase orientation and different degrees of agglomeration. Moreover, HR-TEM revealed interplanar d-spacing planes that are in good agreement with those of the spinel ferrite phase and BTO phase. These techniques along with EDX analyses confirmed the successful formation of the desired nanocomposites. Zeta potential was also investigated. The biological influence of (MFe2O4, CoMFe) MNPs and core–shell (MFe2O4@BTO, CoMFe@BTO) magnetoelectric nanocomposites were examined by MTT and DAPI assays. Post 48 h of treatments, the anticancer activity of MNPs and MENCs was investigated on human colorectal carcinoma cells (HCT-116) against the cytocompatibility of normal non-cancerous cells (HEK-293). It was established that MNPs possess anti-colon cancer capability while MENCs exhibited a recovery effect due to the presence of a protective biocompatible BTO layer. RBCs hemolytic effect of NPs has ranged from non- to low-hemolytic effect. This effect that could be attributed to the surface charge from zeta potential, also the CoMnFe possesses the stable and lowest zeta potential in comparison with CoFe2O4 and MnFe2O4 also to the protective effect of shell. These findings open up wide prospects for biomedical applications of MNPs as anticancer and MENCs as promising drug nanocarriers. [ABSTRACT FROM AUTHOR]

Across the world, paddy fields naturally harbour cyanobacteria that function as biofertilizers and secrete various compounds like Indole-3-acetic acid (IAA) that help organisms in regulating their growth. Also, paddy field farming utilizes large amounts of pesticides (e.g. atrazine); but their continued application in the agricultural field causes toxicity in non-target cyanobacterial species that hinder their performance as a biofertilizer. Hence, the current study is an attempt to ameliorate the atrazine stress in cyanobacterium Cylindrospermum stagnale by addition of IAA (1 mM each) under different atrazine levels (0, 60, 80, 100, 120, 140 µg/l). Atrazine toxicity affected C. stagnale in a dose-dependent manner further experiments revealed that both the exogenous and endogenous IAA mitigated the detrimental effects of atrazine. It reduced MDA content and simultaneously increased chlorophyll content, total protein content, and multiple antioxidant enzyme activities [superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX)] at 140 µg/l. A molecular docking study revealed that the pesticide binds to the D1 protein of the photoelectric chain in photosynthesis. Hence, the application of IAA or cyanobacterial biofertilizer that secretes a sufficient amount of IAA may assist sustainable agriculture in counteracting the atrazine toxicity. [ABSTRACT FROM AUTHOR]

Phytoremediation is one of the environmental-friendly and cost-effective systems for the treatment of wastewater, including industrial wastewater such as palm oil mill effluent final discharge (POME FD). However, the effects of the wastewater on the phytoremediator plants, in term of growth performance, lignocellulosic composition, and the presence of nutrients and heavy metals in the plants are not yet well studied. In the present work, we demonstrated that POME FD increased the growth of P. purpureum. The height increment of P. purpureum supplied with POME FD (treatment) was 61.72% as compared to those supplied with rain water (control) which was 14.42%. For lignocellulosic composition, the cellulose percentages were 38.77 ± 0.29% (treatment) and 34.16 ± 1.01% (control), and the difference was significant. These results indicated that POME FD could be a source of plant nutrients, which P. purpureum can absorb for growth. It was also found that the heavy metals (Al, As, Cd, Co, Cr, Ni and Pb) inside the plant were below the standard limit of the World Health Organization (WHO). Since POME FD was shown to have no adverse effects on P. purpureum, further research regarding the potential application of P. purpureum following phytoremediation of POME FD such as biofuel production is warranted to evaluate its potential use to fit into the waste-to-wealth agenda. [ABSTRACT FROM AUTHOR]

Diabetes is a complex metabolic disorder and different environmental toxicants including heavy metals have been involved in diabetes induction. Therefore, assessment of the environmental risk factors and heavy metals induced toxicity have become critical for reducing the consequences of metals pollutants. Previously, we reported heavy metals induced nephrotoxicity in non-diabetic and diabetic rats. Here, we extended our analysis by examining the heavy metals induced organs (heart, kidney, liver, pancreas, and spleen) damage in diabetic and non-diabetic Wistar rats using histopathology and quantitative real-time PCR (qRT-PCR). Following the generation of the diabetic rat model, the animals were exposed to heavy metals including lead (Pb), arsenic (As), manganese (Mn) and cadmium (Cd). Both non-diabetic and diabetic rats were exposed to heavy metals for 30 days and subsequently, the heart, kidney, liver, pancreas and spleen tissues were examined. Heavy metal treatment resulted in irregularly arranged myofibrils and vacuolization in the heart tissue of metal treated groups as evident from hematoxylin and eosin (H & E) staining. The kidney tissue of rats treated with heavy metals showed tubular degeneration, fibrosis, hemorrhage, and vacuolation. The liver of the heavy metals treated rats exhibited cellular degeneration and necrosis. The pancreatic tissue of streptozotocin injected untreated and metal treated rats revealed severe degeneration, necrosis, degranulation, shrinkage, and depression in the islets of Langerhans. Increased red pulp area and congestion were observed in the spleen of the metal mixture treated non-diabetic and diabetic rats. In line with the histological data, the qRT-PCR analysis showed downregulated expression of Bcl2 and upregulation of Caspase-3 in non-diabetic and diabetic metal treated rats as compared to the non-diabetic untreated rats. In conclusion, the present study revealed, diabetic rats are more prone to metal alone as well as metal mixture induced organ damage as compared to non-diabetic rats. [ABSTRACT FROM AUTHOR]

Cobalt (Co) is an essential component of several enzymes and coenzymes in living organisms. Excess Co is highly toxic to plants. The knowledge of molecular response mechanisms to cobalt stress in plants is still limited, especially in woody plants. The responses of weeping willow (Salix babylonica) seedlings to Co stress were studied using morphological and physiochemical measurements and RNA-seq analysis. The physiological and biochemical indexes such as growth rate, the content of chlorophyll and soluble sugar, photosynthesis and peroxidase activity were all changed in willow seedlings under Co stress. The metal ion concentrations in willow including Cu, Zn and Mg were disturbed due to excess Co. Of 2002 differentially expressed genes (DEGs), 1165 were root-specific DEGs and 837 were stem and leaf-specific DEGs. Further analysis of DEGs showed there were multiple complex cascades in the response network at the transcriptome level under Co stress. Detailed elucidation of responses to oxidative stress, phytohormone signaling-related genes and transcription factors (TFs), and detoxification of excess cellular Co ion indicated the various defense mechanisms in plants respond to cobalt stress. Our findings provide new and comprehensive insights into the plant tolerance to excess Co stress. [ABSTRACT FROM AUTHOR]

Metal pollution has made a significant impact on the earth's ecosystems and tolerance to metals in a wide variety of species has evolved. Metallothioneins, a group of cysteine-rich metal-ion binding proteins, are known to be a key physiological mechanism in regulating protection against metal toxicity. Many rivers across the southwest of England are detrimentally affected by metal pollution, but brown trout (Salmo trutta L.) populations are known to reside within them. In this body of work, two isoforms of metallothionein (MetA and MetB) isolated from trout occupying a polluted and a control river are examined. Using synthetic genetic array (SGA) analyses in the model yeast, Saccharomyces cerevisiae, functional genomics is used to explore the role of metallothionein isoforms in driving metal tolerance. By harnessing this experimental system, S. cerevisiae is used to (i) determine the genetic interaction maps of MetA and MetB isoforms; (ii) identify differences between the genetic interactions in both isoforms and (iii) demonstrate that pre-exposure to metals in metal-tolerant trout influences these interactions. By using a functional genomics approach leveraged from the model yeast Saccharomyces cerevisiae, we demonstrate how such approaches could be used in understanding the ecology and evolution of a non-model species. [ABSTRACT FROM AUTHOR]

The magnetic moment and anisotropy of magnetite nanoparticles can be optimised by doping with transition metal cations, enabling their properties to be tuned for different biomedical applications. In this study, we assessed the suitability of bacterially synthesized zinc- and cobalt-doped magnetite nanoparticles for biomedical applications. To do this we measured cellular viability and activity in primary human bone marrow-derived mesenchymal stem cells and human osteosarcoma-derived cells. Using AC susceptibility we studied doping induced changes in the magnetic response of the nanoparticles both as stable aqueous suspensions and when associated with cells. Our findings show that the magnetic response of the particles was altered after cellular interaction with a reduction in their mobility. In particular, the strongest AC susceptibility signal measured in vitro was from cells containing high-moment zinc-doped particles, whilst no signal was observed in cells containing the high-anisotropy cobalt-doped particles. For both particle types we found that the moderate dopant levels required for optimum magnetic properties did not alter their cytotoxicity or affect osteogenic differentiation of the stem cells. Thus, despite the known cytotoxicity of cobalt and zinc ions, these results suggest that iron oxide nanoparticles can be doped to sufficiently tailor their magnetic properties without compromising cellular biocompatibility. [ABSTRACT FROM AUTHOR]

Ferredoxins are iron-sulfur proteins that play important roles in electron transport and redox homeostasis. Yeast Apd1p is a novel member of the family of thioredoxin-like ferredoxins. In this study, we characterized the hydroxyurea (HU)-hypersensitive phenotype of apd1Δ cells. HU is an inhibitor of DNA synthesis, a cellular stressor and an anticancer agent. Although the loss of APD1 did not influence cell proliferation or cell cycle progression, it resulted in HU sensitivity. This sensitivity was reverted in the presence of antioxidant N-acetyl-cysteine, implicating a role for intracellular redox. Mutation of the iron-binding motifs in Apd1p abrogated its ability to rescue HU sensitivity in apd1Δ cells. The iron-binding activity of Apd1p was verified by a color assay. By mass spectrometry two irons were found to be incorporated into one Apd1p protein molecule. Surprisingly, ribonucleotide reductase genes were not induced in apd1Δ cells and the HU sensitivity was unaffected when dNTP production was boosted. A suppressor screen was performed and the expression of stress-regulated transcription factor Yap1p was found to effectively rescue the HU sensitivity in apd1Δ cells. Taken together, our work identified Apd1p as a new ferredoxin which serves critical roles in cellular defense against HU. [ABSTRACT FROM AUTHOR]