Levels Of Manganese Research Articles

Гормональные, биохимические показатели и уровни микроэлементов крови у молодых женщин с субклиническим гипотиреозом в сочетании с носительством антител к тиреопероксидазе

Many studies have been devoted to investigating the relationship between subclinical hypothyroidism (SH), thyroid gland (TG) autoimmunity, and blood trace elements; however, the data presented in these studies are often contradictory. Aim of study. To identify the factors associated with SH in combination with the presence of Anti-thyroid peroxidase antibody (TPO-Ab). Design. Single-center, observational, single-cohort, cross-sectional, and uncontrolled study. Materials and Methods. This study analyzed 859 women aged 18–45 with SH and without TG dysfunction. Based on thyroid function and TPO-Ab status (presence (+) or absence (–)), four study groups were formed: Group 1 — Euthyroidism and TPO-Ab(–) (n = 503); Group 2 — Euthyroidism and TPO-Ab(+) (n = 164); Group 3 — SH and TPO-Ab(–) (n = 128); Group 4 — SH and TPO-Ab(+) (n = 64). Determination of thyroid-stimulating hormone (TSH), free thyroxine (FT4), and TPO-Ab levels in serum was provided by enzyme immunoassay on the Evolis Robotized System using the test systems "Thyroid-ELISA-TSH, 0.23–3.4 µIU/ml", "Thyroid-ELISA FT4, 10–23.2 pmol/l", and "Thyroid ELISA-TPO-Ab < 30 U/ml". The reference values were taken from the instructions of the manufacturer Alkor Bio Group (Russia). Measurement of element concentrations was conducted on the atomic absorption spectrometer "МГА-915МД" from Lumex (Russia). Logistic regression analysis with a series of univariate and multivariate models was performed to determine independent predictors of the likelihood of SH and TPO-Ab positive status (relative to euthyroid and TPO-Ab negative individuals). Results. In young women, a decrease in FT4 is associated with increasing age, elevated levels of TSH, TPO-Ab, mercury, decreased heart rate, and reduced levels of thyroglobulin, alkaline phosphatase (ALP), manganese, nickel, selenium, lead, and the triglyceride/glucose index. An increase in TSH is associated with lower levels of ALP, manganese, and nickel, and higher mercury levels. The likelihood of having SH combined with the presence of TPO-Ab, compared to the group without thyroid dysfunction and elevated antibodies, increases with reduced concentrations of iodine (odds ratio (OR) = 0.739; 95% confidence interval (CI): 0.618–0.884, p = 0.001), selenium (OR = 0.987; 95% CI: 0.976–0.998, p = 0.018), and zinc (OR = 0.998; 95% CI: 0.997–0.999, p = 0.023), and with elevated lead levels (OR = 1.106; 95% CI: 1.006–1.217, p = 0.038). In a multivariate regression model, the probability also increases with decreased iodine and cadmium levels, and elevated lead levels. Conclusion. Reduced concentrations of iodine, selenium, and zinc, along with elevated blood lead levels, are factors associated with the activation of thyroid autoimmunity and the presence of SH in combination with elevated TPO-Ab levels. Keywords: thyroid gland, thyroid function hormones, microelements, thyroid peroxidase antibodies, young age, women.

Determination of metals in different tissues of Trachurus trachurus from the Marmara Sea and evaluation of their health risks

The present study aimed to determine the differences in metal levels of Aluminum (Al), Cadmium (Cd), Chromium (Cr), Copper (Cu), İron (Fe), Manganese (Mn), Nickel (Ni), Lead (Pb) and Zinc (Zn) between muscle and liver tissues of Trachurus trachurus, the correlation of metal accumulation in tissues with fish length and weight was examined. Health risks and nutritional adequacy were evaluated based on metal levels accumulated in fish muscle. The results demonstrated that fish liver accumulated higher metal levels than muscle. The investigation revealed that the majority of metals present in the tissues of the fish did not exhibit a significant correlation with their size (p>0.05). It can be concluded that fish are not an adequate source of these nutrients because their nutrient levels are below reference values. The fish were found to be nutrient deficient, as the levels of nutrients were below reference values. The estimated daily intakes of all metals accumulated in muscle were below reference doses. The target hazard coefficient and target hazard index values were less than 1. Lifetime carcinogenic risk values were below 10-4, and total carcinogenic risk values were within the acceptable range. Pb and Cd concentrations in muscle exceeded the tolerable limit. The daily amount of fish that could be consumed without non-carcinogenic health risk was 181 grams for Cd and 295 grams for Pb. The daily amount of fish that could be consumed without carcinogenic health risk was 1.21 grams for Cd and 231 grams for Pb.

Is the concentration of heavy metals in sun-dried Engraulicypris sardella (Günther, 1868) in Malawi, a human health risk?

The effects of trophic cascades have made small-size pelagic fish species, such as Engraulicypris sardella, from Lake Malawi an important ecological and food system. However, human-induced activities can potentially pollute Lake Malawi exposing E. sardella to heavy metals contamination. This could pose a food system health risk to the population of Malawians and neighboring countries, which heavily rely on fish as a source of animal protein. Therefore, this study investigated the concentration levels of Lead (Pb), Cadmium (Cd), Zinc (Zn), Copper (Cu), Manganese (Mn), and Iron (Fe) in sun-dried E. sardella and conducted a health risk assessment associated with its consumption. E. sardella samples were collected from Karonga, Nkhata Bay, Nkhotakota, Salima, and Mangochi districts in Malawi between December 2023 and February 2024. The results revealed significant variations in Cd, Zn, Cu, Mn, and Fe concentrations among the sampled sites while Pb contamination was not detected. The concentrations of Zn, Cu, Mn, and Fe in E. sardella were within acceptable consumption limits set by the Food and Agriculture Organization (FAO) and the World Health Organization (WHO) in 2012. However, the fish's average Cd levels (0.17 mg kg−1 ww) were slightly above the recommended threshold of 0.1 mg kg−1 ww by FAO/WHO (2012) but remained below the limit of 0.5 mg kg−1 ww set by FAO in 1983. Furthermore, none of the analyzed heavy metals posed a health risk effect to people. Therefore, there is a need for regular monitoring of heavy metal concentrations in E. sardella and other mostly consumed fish species from Lake Malawi, both fresh and processed, for a sustained guarantee of the safety of the fish consumers.

Коррекция дисэлементоза у детей первого года жизни, внутриутробное развитие которых проходило в условиях военного конфликта

Aim. To study peculiarities and to optimise the micro- and macroelemental status of children during the first year of life, the prenatal development of which fell at a military conflict. Design. Phase one was a retrospective analysis of medical documents (medical history of a pregnant woman, labour and delivery medical record, infant's record; phase two was comparison of the elemental composition of children's hair. Materials and methods. The study included 154 children less than a year of age: prenatal development of 81 children fell at a military conflict (study group) and 73 children — during the time of peace (controls). Children in both groups were formula-fed as their mothers had agalactia because of stress caused by military actions. Elemental composition of children's hair was determined using an AAC 2280 Perkin Elmer atomic absorption spectrophotometer (USA); identified diselementosis was corrected with introduction of an adapted and enriched formula, and the analysis was repeated in 6 months. Results. The first analysis revealed imbalance in micro- and macroelemental composition of children's hair in the study group: lower levels of iron, copper, selenium, magnesium, zinc, manganese and potassium, as well as accumulation of toxic elements — lead, cadmium, chrome. A repeated analysis showed significant optimisation of essential micro- and macroelements, as well as reduction in the level of toxic microelements in children's hair. Conclusion. Prenatal development during an active military conflict causes diselementosis, which leads to somatic pathologies in children of both neonates and infants. An optimal formula makes it possible to correct elemental imbalances during the first year of child's life. Keywords: diselementosis, essential and toxic elements, correction.

TRACE METAL ANALYSIS IN GROUNDWATER OF THE HANDRI RIVER BASIN, KURNOOL DISTRICT, ANDHRA PRADESH, INDIA

Quantitative analysis of trace metals in the groundwater of the Handri river basin was conducted using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Descriptive statistics, box whisker plots, and GIS assessed their spatial distribution in South India. The elements arsenic, cadmium, and iron were the most abundant, with iron having the highest concentration and copper the lowest. Chromium, copper, nickel, and zinc complied with BIS and WHO standards for drinking water. In certain locations of the Handri river basin, elevated concentrations of arsenic, cadmium, iron, lead, and manganese were found to be polluting and endangering the water. A comprehensive analysis revealed that, out of 41 water quality sites, copper, chromium, nickel, and zinc were within acceptable limits, while arsenic and cadmium exceeded the limits. Twenty groundwater sites showed elevated iron content, revealed by a spatial distribution map. Excessive manganese and lead levels were observed in specific stations, such as Gorantla, Bondi Madugula, Ramachandrapuram, Konganapadu, and Tangaradona. The study suggests that population growth and industrialization contribute to resource depletion and environmental deterioration. The cohesive findings from descriptive models, box whisker plots, and spatial analyses aim to guide decision-makers in developing adaptive groundwater trace element monitoring strategies for the Handri basin in Kurnool district, India.

Nutrient Solution Application of a Calcium-mobilizing Biostimulant Mitigates Tipburn without Decreasing Biomass of Greenhouse Hydroponic Lettuce

Lettuce tipburn is a physiological disorder characterized by marginal necrosis and curling of inner, younger leaves caused by localized calcium deficiency, especially in low evapotranspiration environments that restrict mass flow and thus calcium mobility. Severe tipburn negatively affects the marketability and quality of greenhouse-grown hydroponic lettuce. We aimed to assess the effectiveness of a chemical-based, calcium-mobilizing biostimulant for mitigating lettuce tipburn when applied in hydroponic nutrient solutions. Butterhead lettuce (Lactuca sativa ‘Rex’) was grown indoors under warm-white light-emitting diodes at a mean photosynthetic photon flux density of 300 μmol⋅m−2⋅s−1 for 11 days. Subsequently, we transplanted seedlings into deep-water-culture hydroponic trays in a greenhouse at an air temperature of 24.6 ± 1.2 °C, relative humidity of 76.2% ± 7.4%, and 20-hour photoperiod with supplemental lighting from high-pressure sodium lamps. The plants were grown in nutrient solutions with and without the biostimulant codenamed CC US-2105 at two concentrations (22 and 220 μL⋅L−1). Data were collected from plant samples at three harvests at 14, 21, and 28 days after transplant (DAT). At 14 DAT, there was no tipburn under any treatments. Compared with the control, the biostimulant at 22 μL⋅L−1 increased shoot dry mass by 31%. At 21 DAT, the biostimulant at 220 μL⋅L−1 eliminated tipburn, and the biostimulant increased shoot fresh weight by 28%, irrespective of the concentration. At 28 DAT, despite sufficient calcium in the whole plant and the remaining nutrient solution, severe tipburn still occurred in plants that did not receive the biostimulant (control). Compared with the control, the biostimulant at the higher concentration of 220 μL⋅L−1 decreased the tipburn rating by 88% and the number of leaves with tipburn by 85%, increased the plant diameter by 11%, increased the total leaf number by six, and accumulated higher levels of manganese and zinc. In contrast, these parameters remained unaffected at the lower biostimulant concentration of 22 μL⋅L−1. At 28 DAT, shoot biomass was unaffected by the biostimulant. In conclusion, the calcium-mobilizing biostimulant is an effective strategy to mitigate hydroponic lettuce tipburn without decreasing biomass accumulation in greenhouse conditions.

Evaluation of Some Biochemical Parameters in Glucose-6-Phosphate Dehydrogenase deficient subjects of Hausa and Fulani ethnics

Glucose-6-phosphate dehydrogenase deficiency is a significant public health problem that is implicated in the pathogenesis of a number of common diseases via increased oxidative stress and a decrease in the generation of nitric oxide. There is little information about its impact on some organ, hence the need for this research. This was a case-control study carried out on Hausa and Fulani ethnics in Kano. Heparinized 5 ml venous blood specimen were collected from 140 individuals (70 deficient and 70 control) aged between 18-35 years selected for the study to determine the blood levels of some biochemical parameters using standard methods. There were significant increase in transaminases (p<0.001), but significant decrease concentrations of sodium (p<0.05), chloride (p<0.001), alkaline phosphatase (p<0.001) and total protein (p<0.001) whereas there was no statistically significant difference (p>0.05) in the plasma concentration of albumin, total bilirubin, conjugated bilirubin, urea, creatinine, potassium and bicarbonate ions. Our results demonstrate extremely significantly lower (p<0.001 for all) concentration in glutathione reductase, total antioxidants potential, copper, zinc and non-significant decrease (p>0.05) in manganese level of G-6-PD deficient patients compared to controls, whereas malondialdehyde level showed an increasing trend on contrary. However, there were correlations between G-6-PD activity and oxidative stress markers. The findings of the present study suggest that liver and kidneys functions were not altered among people living with G-6-PD deficiency but induce oxidative stress which is not capable of causing organ impairment.

Association of per- and polyfluoroalkylated substances/heavy metals and bone health in children and adolescents.

Research on the correlation between exposure to per- and polyfluoroalkylated substances (PFASs)/heavy metals and bone health during childhood and adolescence is limited. Considering their role as endocrine disruptors, we examined relationships of six PFASs and three heavy metals with bone mineral density (BMD) in children and adolescents using representative samples from the National Health and Nutrition Examination Survey (NHANES). The study included 622 participants aged 12-19. The relationship between single pollutant and lumbar spine and total BMD was studied using linear regression analyses. Additionally, Bayesian Kernel Machine Regression (BKMR) models were applied to assess the joint effects of multiple PFASs and heavy metals exposure on the lumbar spine and total BMD. Statistically significant differences were noted in the serum concentrations of perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), blood lead (Pb), and blood manganese (Mn) between male and female participants (all p < 0.05). Single-exposure studies have shown that Mn was negatively correlated with lumbar spine BMD and total BMD. Multivariate linear regression models revealed that, in the male group, total bone density decreased as the blood PFOA levels [95% CI = (-0.031, -0.001), p = 0.040] and blood manganese levels [95% CI = (-0.009, -0.002), p = 0.004] increased. Similarly, lumbar spine bone density decreased as the blood manganese levels [95% CI = (-0.011, -0.002), p = 0.009] increased. In the female group, total bone density decreased as the serum PFNA levels [95% CI = (-0.039, 0.000), p = 0.048] increased. As shown in the BKMR model, the joint effects of pollutant mixtures, including Mn, were negatively associated with both the lumbar spine and total BMD. Among the pollutants analyzed, Mn appeared to be the primary contributor to this negative association. This study suggests that exposure to certain PFASs and heavy metals may be associated with poor bone health. Childhood and adolescence are crucial stages for bone development, and improper exposure to PFASs and heavy metals during these stages could potentially jeopardize future bone health, consequently raising the risk of osteoporosis in adulthood.

A Novel Role for the Longevity-Associated Protein SLC39A11 as a Manganese Transporter.

The identification of aging- and longevity-associated genes is important for promoting healthy aging. By analyzing a large cohort of Chinese centenarians, we previously found that single-nucleotide polymorphisms (SNPs) in the SLC39A11 gene (also known as ZIP11) are associated with longevity in males. However, the function of the SLC39A11 protein remains unclear. Here, we found that SLC39A11 expression is significantly reduced in patients with Hutchinson-Gilford progeria syndrome (HGPS). In addition, we found that zebrafish with a mutation in slc39a11 that significantly reduces its expression have an accelerated aging phenotype, including a shortened average lifespan, muscle atrophy and reduced swimming, impaired muscle regeneration, gut damage, and abnormal morphology in the reproductive system. Interestingly, these signs of premature aging were more pronounced in male zebrafish than in females. RNA-sequencing analysis revealed that cellular senescence may serve as a potential mechanism for driving this slc39a11 deficiency-induced phenotype in mutant zebrafish. Moreover, immunofluorescence showed significantly increased DNA damage and reactive oxygen species signaling in slc39a11 mutant zebrafish. Using inductively coupled plasma mass spectrometry (ICP-MS), we found that manganese significantly accumulates in slc39a11 mutant zebrafish, as well as in the serum of both global Slc39a11 knockout and hepatocyte-specific Slc39a11 knockout mice, suggesting that this metal transporter regulates systemic manganese levels. Finally, using cultured human fibroblasts, we found that both knocking down SLC39A11 and exposure to high extracellular manganese increased cellular senescence. These findings provide compelling evidence that SLC39A11 serves to protect against the aging process, at least in part by regulating cellular manganese homeostasis.

Analysis of the Impact of Coal Mineacid Water on River Water Quality, Biota, and Human Health Around Mining

Acid Mine Drainage (AMD) or Acidic Acidic Drainage (AAT) is a type of water runoff that happens when certain sulfide minerals in rocks come in contact with water and oxygen, triggering an oxidation process that results in water with acidic properties. To understand more about this phenomenon, a literature review was conducted using relevant keywords on online information sources. The indicators used to measure the level of acidity in mine water include pH, metal concentration, Total Suspended Solid (TSS) or turbidity level, electrical conductivity, sulfate, and sulfuric acid content. High electrical conductivity in mine water usually indicates the presence of metals such as iron (Fe) and manganese (Mn). High levels of manganese (Mn) in water can cause health problems for humans. Moreover, an increase in the concentration of Fe can cause an increase in turbidity or TSS because iron metal can dissolve in air and form solid particles that can cause turbidity. To reduce acidity and environmental pollution, passive or active treatment techniques can be used to neutralize AMD.

Analysis of Heavy Metals Contaminating Water and Fish Species in Kwanar-Are Dam, Katsina State, Nigeria

This work is aimed to determine the quantities of heavy metals in the water, and three different fish species (Bugrus bayad, Tilapia, and synoduntis) present in Kwanar Are Dam. In the adjacent villages, the dam provides the main water supply for domestic uses, agriculture, fishing, and drinking. Water and fish samples were examined using an Atomic Absorption Spectrophotometer (AAS) to measure the levels of heavy metals. The water sample tested positive for Cd 0.183 mg/l, Cu 0.286 mg/l, Cr 0.233 mg/l, Mn 0.081 mg/l, Ni 0.179 mg/l, Pb 0.166 mg/l, and Zn 0.145 mg/l, according to the results. Cu, Mn, and Ni were below the World Health Organization (WHO) recommended levels. However, Cd, Cr, Pb, and Zn exceeded these limits. The levels of heavy metals in the fish samples ranged from 0.275 to 0.581 mg/kg for Cadmium, 0.520 to 0.837 mg/kg for Copper, 0.205 to 0.512 mg/kg for Nickel, 0.205 to 0.512 mg/kg for Lead, and 0.333 to 0.611 mg/kg for Tilapia, Bugrus, and Synoduntis fish, respectively. Chromium, Lead, Cadmium, Nickel, Zinc, and Manganese levels were lower than copper concentrations. Manganese and nickel concentrations in the fish exceeded what the WHO considered safe. The results of this study show that heavy metals have accumulated in the fish species that live in the Kwanar Are Dam, proving that the dam is contaminated. While some heavy metals in the water and fish samples were within the World Health Organization (WHO)'s (recommended limits), others, including Cd, Cr, Pb, and Zn, were over these levels. This suggests a possible health danger for the locals who depend on the dam as their main water source for daily activities.

Manganese-induced miR-125b-2-3p promotes anxiety-like behavior via TFR1-mediated ferroptosis

The toxic effects of excessive manganese (Mn) levels in the environment have led to a severe public health concern. Ferroptosis is a newly form of cell death relying on iron, inherent to pathophysiological processes of psychiatric disorders, such as anxiety and depression-like behaviors. Excessive Mn exposure causes various neurological effects, including neuronal death and mood disorders. Whether Mn exposure causes anxiety and depression-like behaviors, and the underlying mechanisms of Mn-induced ferroptosis have yet to be determined. Here, Mn-exposed mice showed anxiety-like behavior. We also confirmed the accumulation of ferrous ion (Fe2+), lipid peroxidation, and depletion of antioxidant defense system both in vitro and in vivo Mn-exposed models, suggesting that Mn exposure can induce ferroptosis. Furthermore, Mn exposure downregulated the expression of miR-125b-2-3p. In turn, overexpression of miR-125b-2-3p alleviated the Mn-induced ferroptosis by targeting Transferrin receptor protein 1 (TFR1). In summary, this novel study established the propensity of Mn to cause anxiety-like behavior, an effect that was regulated by miR-125b-2-3p and ensuing ferroptosis secondary to the targeting of TFR1. These results offer promising targets for the prevention and treatment of Mn-induced neurotoxicity.

Characterization of a Southern Ocean deep chlorophyll maximum: Response of phytoplankton to light, iron, and manganese enrichment

AbstractSouthern Ocean phytoplankton growth is limited by low iron (Fe) supply and irradiance, impacting the strength of the biological carbon pump. Unfavorable upper ocean conditions, such as low nutrient concentrations, can lead to the formation of deep chlorophyll or biomass maxima (DCM/DBM). While common in the Southern Ocean, these features remain understudied due to their subsurface location. To increase our understanding of their occurrence, we studied the responses of phytoplankton communities from a Southern Ocean DCM to increasing light, Fe, and manganese (Mn) levels. The DCM communities were light‐ and Fe‐limited, but light limitation did not increase phytoplankton Fe requirements. The greatest physiological responses were observed under combined Fe/light additions, which stimulated macronutrient drawdown, biomass production and the growth of large diatoms. Combined Mn/light additions induced subtle changes in Fe uptake rates and community composition, suggesting species‐specific Mn requirements. These results provide valuable information on Southern Ocean DCM phytoplankton physiology.

Promotion of Sulfur Vacancies and Mn Substitution in Few-Layered Molybdenum Disulfide Towards Superior Hydrogen Evolution in Acid

The superior features of hydrogen as an energy source with high energy density (120 MJ kg-1) and zero CO2 emission, makes it a strong candidate for replacing fossil fuels. Recently the European Commission has pledged to invest €470 billion in renewable hydrogen technologies by 2050, with a significant portion of this investment expected to be allocated for the deployment of renewable hydrogen electrolyzers by 2030. Water electrolysis via Proton Exchange Membrane (PEM) with Pt/Pd-based noble metals as a cathode, is currently the most effective method for hydrogen production, but alternatives are highly needed due to the scarcity and the higher cost of these metals. One of the promising classes of electrocatalysts for hydrogen evolution reaction (HER) is transition metal dichalcogenides (TMDs), and among them molybdenum disulfide (MoS2) has shown promising properties as an electrocatalyst for hydrogen production. MoS2 has different phases of 1T, 2H, and 3R with 2H-MoS2 being the most promising electrocatalyst for hydrogen production due to its semiconductive behavior and long-term stability. However, the poor conductivity, large band gap and no active basal plane towards HER limits the applications of 2H-MoS2 for water electrolysis in PEM cells. Strategies such as introduction of defects, S-vacancies, edge engineering and doping can result in enhanced HER activity of 2H-MoS2. Incorporating different transition metals (Ni, Co, Mn, Fe) into MoS2 lattice can increase the number of active sites and improve charge transfer during the electrocatalytic reaction. Based on Density Functional Theory (DFT) studies, insertion of Mn into MoS2 layer can decrease the bandgap to zero, resulting in large number of available electronic states around the Fermi level. In this work we introduce Mn doped MoS2 produced via a cost-effective microwave-assisted solid-state approach to explore the potential of few-layered MoS2, doped with different levels of manganese (5%, 10% and 15% at.) for HER in acidic media. The electrocatalytic activity towards HER reveals that 10% at. Mn incorporation into MoS2 lattice, reduces the overpotential (η10) from 210 mV for pristine MoS2 to 148 mV for 10%Mn-MoS2, respectively. In addition, Tafel slope analysis has confirmed a faster kinetics of 10%Mn-MoS2 (53 mV dec-1) compared to MoS2 (75 mV dec-1) revealing the Volmer–Heyrovsky mechanism as the rate determining step (rds). Further characterization by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and DFT studies show that Mn substitution promotes the creation of sulfur vacancies, which in turn enhances the catalytic activity towards HER. Additionally, the 10% Mn-doped MoS2 demonstrates remarkable activity in a single-cell PEM electrolyzer with long-term durability. This study highlights the potential of Mn doped MoS2 as an efficient, low-cost electrocatalyst for hydrogen production, with implications for the development of a sustainable hydrogen economy. Figure 1

Traditional Food Consumption and Other Determinants of Exposure for Lead, Cobalt, Manganese, and Hexachlorobenzene in Northern Canada

Results of a 2019 human biomonitoring study indicated that several parameters, including lead, cobalt, manganese, and hexachlorobenzene, were elevated in blood and urine samples in Old Crow, Yukon, in comparison to the general Canadian population. This study aims to identify possible local determinants of levels of these parameters, including consumption of locally harvested traditional foods, lifestyle factors, and demographics, in Old Crow and, for comparison, two other northern populations: communities in the Dehcho and Sahtú regions of the Northwest Territories. We ran generalized linear models to identify possible associations between individual determinants of exposure and key biomarkers, controlling for age and sex. In Old Crow, several variables were associated with elevated exposure levels of these biomarkers, including drinking untreated river water (29% higher blood manganese levels and 120% higher blood lead levels), eating caribou kidneys (22% higher blood manganese levels and 58% higher blood lead levels), and eating whitefish (28% higher blood cobalt levels). Additionally, in order to differentiate results in Old Crow from those in other northern regions and to identify trends across regions, we observed relationships between consumption of moose and caribou organs and lead and hexachlorobenzene levels in the reference populations and pooled population groups. Though levels of particular contaminants may be elevated in some traditional foods, these foods remain an important source of nutrients for members in these communities and provide other benefits, including increased physical activity through harvesting, mental health improvements, and spiritual wellness.

Proteomic Study of Broiler Plasma Supplemented with Different Levels of Copper and Manganese from Different Sources.

The aim of the present study was to evaluate the differential expression of plasma proteins in broiler chickens supplemented with different sources (sulfates and hydroxychlorides) and levels of copper (15 and 150 mg kg-1) and manganese (80 and 120 mg kg-1). For this, plasma samples from 40 broiler chickens were used, divided into four experimental groups: S15-80 (15 ppm CuSO4 and 80 ppm MnSO4), S150-120 (150 ppm CuSO4 and 120 ppm MnSO4), H15-80 (15 ppm Cu(OH)Cl and 80 ppm Mn(OH)Cl), and H150-120 (150 ppm Cu(OH)Cl and 120 ppm Mn(OH)Cl). From plasma samples obtained from each bird from the same treatment, four pools were made considering 10 birds per group. Plasma proteome fractionation was performed by 2D-PAGE. Concentrations of the studied minerals were also evaluated in both plasma and protein pellet samples. A higher concentration of Cu and Mn was observed in the plasma and protein pellets of groups that received higher mineral supplementation levels compared to those receiving lower levels. Mn concentrations were higher in plasma and protein pellets of the hydroxychloride-supplemented groups than the sulfate-supplemented groups. Analysis of the gels revealed a total of 40 differentially expressed spots among the four treatments. Supplementation with different sources of minerals, particularly at higher levels, resulted in changes in protein regulation, suggesting a potential imbalance in homeostasis.

Environmental monitoring: Tobara fish as bioindicators of heavy metal pollution in a coastal ecosystem

This study aims to evaluate the liver, gill, and muscle tissue heavy metal accumulation of the thin lip mullet (Chelon ramada) from Ain Ziana Lagoon, Benghazi. The heavy metals included zinc, copper, lead, and manganese. Between September 2021 and August 2022, specimens were collected on a monthly basis. They were identified using DNA barcoding, namely the CO1 gene, which is associated with the sequence that is BankIt in the NCBI gene bank (accession number OR533708). The research tracked the lagoon's physicochemical characteristics, finding that heavy metal concentrations spiked in the summer and that water temperature, pH, and salinity varied throughout the year. Except for copper in the winter, lead, manganese, and copper levels were all above acceptable limits, according to a comparison with EPA (2005) regulations. On the other hand, zinc levels were under these limitations. The amounts of all metals in the sediment regularly exceeded the limits set by the EPA. Zinc and manganese levels in fish tissues were within the approved ranges according to WHO and FAO standards but lead and manganese levels were far higher than allowed, indicating possible pollution from sewage or industrial sources. There were noticeable seasonal patterns in bioaccumulation, especially during the warmer months, but manganese did not exhibit a distinct pattern. Also noted that the thin lip mullet's mineral absorption and release capacities varied with the different seasons and tissues. Lastly, the Metal Pollution Index (MPI) showed that there was a larger possibility for bioaccumulation in the liver, gill, and muscle during the study period.

Optimizing phosphate removal by manipulating manganese and cobalt levels in soil aquifer treatment system

Manganese (Mn2+) and cobalt (Co2+) metals have been reported to exhibit complex interactions with phosphate (PO43-) ions, which can influence their mobility, reactivity, and removal behavior in soil aquifer treatment system (SAT). This study aimed to investigate the role of manganese (Mn2+) and cobalt (Co2+) in phosphate (PO43-) removal within a soil aquifer treatment system. A lab-scale column experiment was conducted using sand as the filtration media, and a synthetic wastewater containing 20 mg/L PO43-, 60 mg/L Mn2+, and 40 mg/L Co2+ was used. The breakthrough curves showed efficient removal of PO43- during the infiltration process, with concentrations reaching as low as 1 mg/L. The regression analysis revealed that Mn2+ had a strong negative correlation effect on PO43- concentration, indicating its stimulatory role in PO43- removal. Conversely, Co2+ showed a strong positive correlation effect, suggesting its promoting effect on PO43- concentration. Optimization analysis identified optimal concentrations of 57.4 mg/L for Mn2+ and 4.8 mg/L for Co2+ that interacted with lower PO43- concentrations, achieving the desired outcome of reducing PO43- levels. These findings highlight the importance of considering Mn2+ and Co2+ concentrations in soil aquifer treatment systems for effective phosphate removal.

Associations of multiple toxic metal exposures with metabolic dysfunction-associated fatty liver disease: NHANES 2011-2018.

The occurrence of metabolic dysfunction-associated fatty liver disease (MASLD) is driven by multiple factors including obesity, hypertension, dyslipidemia, and insulin resistance. However, epidemiological research investigating the association between metal exposure and MASLD occurrence remains limited. We conducted a large cross-sectional study with 6,520 participants who were involved in the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2018. Using generalized linear regression, we examined the relationship between five heavy metals (mercury, manganese, lead, selenium, cadmium) and MASLD. Furthermore, restricted cubic spline models and weighted quantile sum (WQS) analysis were employed to characterize the exposure-response relationship between the five metals and MASLD. Higher blood selenium levels were associated with an increased likelihood of MASLD among US adults. Blood lead exposure was also positively correlated with MASLD risk. However, there was no significant association observed between blood cadmium, mercury, manganese levels, and MASLD risk. Among the five metals, blood cadmium exposure accounted for the highest proportion of MASLD risk. Our study indicated the significant association between blood cadmium and lead exposure levels and the occurrence of MASLD in a representative sample of US adults.

A critical role for iron and zinc homeostatic systems in the evolutionary adaptation of Escherichia coli to metal restriction.

Host nutritional immunity utilizes metal deprivation to help prevent microbial infection. To investigate bacterial adaptation to such restrictive conditions, we conducted experimental evolution with two metal sequestering agents. Ethylenediaminetetraacetic acid (EDTA) and diethylenetriamine pentamethylene phosphonic acid (DTPMP) were selected as ligands because they differentially affect cellular levels of iron, manganese and zinc in Escherichia coli. Mutants of E. coli strain BW25113 were isolated after cultivation at sub-minimum inhibitory concentration (MIC) chelant levels and genetic changes potentially responsible for tolerance were identified by whole-genome sequencing. In EDTA-selected strains, mutations in the promoter region of yeiR resulted in elevated gene expression. The yeiR product, a zinc-specific metallochaperone, was confirmed to be primarily responsible for EDTA resistance. Similarly, in two of the DTPMP-selected strains, a promoter mutation increased expression of the fepA-entD operon, which encodes components of the ferric-enterobactin uptake pathway. However, in this case improved DTPMP tolerance was only detectable following overexpression of FepA or EntD in trans. Additional mutations in the cadC gene product, an acid-response regulator, preserved the neutrality of the growth medium by constitutively activating expression of the cadAB regulon. This study uncovers specific resistance mechanisms for zinc and iron starvation that could emerge by selection against host nutritional immunity or competition with heterologous metallophores. It also provides insight into the specific metals affected by these two widely used chelators critical for their antibacterial mode of action.