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Memorias Do Instituto Oswaldo Cruz 2023The Amazon Region hosts invaluable and unique biodiversity as well as mineral resources. Consequently, large illegal and artisanal gold mining areas exist in indigenous...
BACKGROUND
The Amazon Region hosts invaluable and unique biodiversity as well as mineral resources. Consequently, large illegal and artisanal gold mining areas exist in indigenous territories. Mercury has been used in gold mining, and some has been released into the environment and atmosphere, primarily affecting indigenous people such as the Yanomami. In addition, other heavy metals have been associated with gold mining and other metal-dispersing activities in the region.
OBJECTIVE
Investigate the gut microbiome of two semi-isolated groups from the Amazon, focusing on metal resistance.
METHODS
Metagenomic data from the Yanomami and Tunapuco gut microbiome were assembled into contigs, and their putative proteins were searched against a database of metal resistance proteins.
FINDINGS
Proteins associated with mercury resistance were exclusive in the Yanomami, while proteins associated with silver resistance were exclusive in the Tunapuco. Both groups share 77 non-redundant metal resistance (MR) proteins, mostly associated with multi-MR and operons with potential resistance to arsenic, nickel, zinc, copper, copper/silver, and cobalt/nickel. Although both groups harbour operons related to copper resistance, only the Tunapuco group had the pco operon.
CONCLUSION
The Yanomami and Tunapuco gut microbiome shows that these people have been exposed directly or indirectly to distinct scenarios concerning heavy metals.
Topics: Humans; Copper; Nickel; Silver; Metals, Heavy; Mercury; Gold; Microbiota
PubMed: 37971084
DOI: 10.1590/0074-02760230086 -
Environmental Science and Pollution... Oct 2023Some heavy metals are associated with periodontitis; whereas most of these associations have focused on individual metal, there are no specific studies on the effects of...
Some heavy metals are associated with periodontitis; whereas most of these associations have focused on individual metal, there are no specific studies on the effects of combined heavy metal exposure on periodontitis. We conducted an analysis on the association between urinary heavy metal exposure and periodontitis in participants aged 30 years and older using multiple logistic regression and Bayesian kernel machine regression (BKMR). This analysis was performed on data from the National Health and Nutrition Examination Survey from 2011 to 2014. The study found that using logistic regression, the 4th quartile of urinary lead and molybdenum and the 3rd quartile of urinary strontium were positively associated with periodontitis compared to the reference quartile after adjusting for covariates. Odds ratio (OR) with 95% confidence interval (CI) was 1.738 (1.069-2.826), 1.515 (1.025-2.239), and 1.498 (1.010-2.222), respectively. The 3rd and 4th quartiles of urinary cobalt were negatively associated with periodontitis, and their ORs and 95% CIs were 0.639 (0.438-0.934) and 0.571 (0.377-0.964), respectively. The BKMR model showed that urinary barium, lead, and molybdenum were positively associated with periodontitis in a range of concentrations and urinary cobalt, manganese, tin, and strontium were negatively correlated with periodontitis. Furthermore, the overall association between urinary heavy metals and periodontitis was positive. Our study provides evidence for an association between exposure to multiple urinary heavy metals and periodontitis. However, further longitudinal studies are needed to explore the specific mechanisms involved.
Topics: Adult; Humans; Nutrition Surveys; Molybdenum; Bayes Theorem; Metals, Heavy; Cobalt; Periodontitis; Strontium; Cadmium
PubMed: 37740806
DOI: 10.1007/s11356-023-29888-6 -
The Science of the Total Environment Jan 2024Colorectal cancer is a major public health concern, with increasing incidence and mortality rates worldwide. Environmental factors, including exposure to toxic metals,... (Review)
Review
Colorectal cancer is a major public health concern, with increasing incidence and mortality rates worldwide. Environmental factors, including exposure to toxic metals, such as lead, chromium, cadmium, aluminium, copper, arsenic and mercury, have been suggested to play a significant role in the development and progression of this neoplasia. In particular, the bioaccumulation of toxic metals can play a significant role in colorectal cancer by regulating biological phenomenon associated to both cancer occurrence and progression, such as cell death and proliferation. Also, frequently these metals can induce DNA mutations in well-known oncogenes. This review provides a critical analysis of the current evidence, highlighting the need for further research to fully grasp the complex interplay between toxic metal bioaccumulation and colorectal cancer. Understanding the contribution of toxic metals to colorectal cancer occurrence and progression is essential for the development of targeted preventive strategies and social interventions, with the ultimate goal of reducing the burden of this disease.
Topics: Humans; Bioaccumulation; Metals; Arsenic; Cadmium; Mercury; Heavy Metal Poisoning; Colorectal Neoplasms; Metals, Heavy
PubMed: 37813250
DOI: 10.1016/j.scitotenv.2023.167667 -
Ecotoxicology (London, England) Nov 2023Elevated heavy metal concentrations in soils are a cause for concern as they are hazardous to soil organisms including earthworms which are considered as ecosystem...
Elevated heavy metal concentrations in soils are a cause for concern as they are hazardous to soil organisms including earthworms which are considered as ecosystem engineers. Current ecotoxicity tests predominantly use temperate earthworm species, and thus there is the need to include a broader genera of native species to improve ecological risk assessment. Alma nilotica, is a tropical anecic earthworm species that survives well under laboratory conditions and has potential for use in ecotoxicology testing but lacks published toxicity data for important pollutants. Growth and reproduction bioassays were carried out with A. nilotica to determine the relationship between the concentrations of Cu, Zn, Pb and Cr in spiked soils and their bioaccumulation and toxic effects. Positive linear relationships were found between soil-metal and internal earthworm-metal concentrations. Cu did not inhibit growth up to 35 days of exposure but became toxic with longer exposure duration. Zn was not regulated by A. nilotica although it is an essential metal that is well regulated by Eisenia sp. commonly used in standard ecotoxicity tests, showing differences in metal regulation by earthworms of different ecological categories. Based on bioaccumulation factors (BAFs), growth inhibition and reproduction effects the metals were ranked in decreasing toxicity as Pb > Cr > Zn > Cu. The mean 20% Internal Effects Concentrations (IEC20s) for reproduction were 1.04, 2.9, 8.3 and 224.2 mg metal kg earthworm for Pb, Cr, Zn and Cu respectively. These data can contribute to the improvement of metal risk assessment particularly in tropical contexts.
Topics: Animals; Oligochaeta; Ecosystem; Lead; Soil Pollutants; Metals, Heavy; Reproduction; Soil
PubMed: 37864594
DOI: 10.1007/s10646-023-02707-x -
Acta Biomaterialia Aug 2023Zn and its alloys are increasingly under consideration for biodegradable bone fracture fixation implants owing to their attractive biodegradability and mechanical...
Metal-organic Zn-zoledronic acid and 1-hydroxyethylidene-1,1-diphosphonic acid nanostick-mediated zinc phosphate hybrid coating on biodegradable Zn for osteoporotic fracture healing implants.
Zn and its alloys are increasingly under consideration for biodegradable bone fracture fixation implants owing to their attractive biodegradability and mechanical properties. However, their clinical application is a challenge for osteoporotic bone fracture healing, due to their uneven degradation mode, burst release of zinc ions, and insufficient osteo-promotion and osteo-resorption regulating properties. In this study, a type of Zn coordinated zoledronic acid (ZA) and 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP) metal-organic hybrid nanostick was synthesized, which was further mixed into zinc phosphate (ZnP) solution to mediate the deposition and growth of ZnP to form a well-integrated micro-patterned metal-organic/inorganic hybrid coating on Zn. The coating protected noticeably the Zn substrate from corrosion, in particular reducing its localized occurrence as well as suppressing its Zn release. Moreover, the modified Zn was osteo-compatible and osteo-promotive and, more important, performed osteogenesis in vitro and in vivo of well-balanced pro-osteoblast and anti-osteoclast responses. Such favorable functionalities are related to the nature of its bioactive components, especially the bio-functional ZA and the Zn ions it contains, as well as its unique micro- and nano-scale structure. This strategy provides not only a new avenue for surface modification of biodegradable metals but also sheds light on advanced biomaterials for osteoporotic fracture and other applications. STATEMENT OF SIGNIFICANCE: Developing appropriate biodegradable metallic materials is of clinical relevance for osteoporosis fracture healing, whereas current strategies are short of good balance between the bone formation and resorption. Here, we designed a micropatterned metal-organic nanostick mediated zinc phosphate hybrid coating modified Zn biodegradable metal to fulfill such a balanced osteogenicity. The in vitro assays verified the coated Zn demonstrated outstanding pro-osteoblasts and anti-osteoclasts properties and the coated intramedullary nail promoted fracture healing well in an osteoporotic femur fracture rat model. Our strategy may offer not only a new avenue for surface modification of biodegradable metals but also shed light on better understanding of new advanced biomaterials for orthopedic application among others.
Topics: Rats; Animals; Zoledronic Acid; Osteoporotic Fractures; Biocompatible Materials; Phosphates; Alloys; Zinc; Absorbable Implants; Corrosion; Materials Testing
PubMed: 37196904
DOI: 10.1016/j.actbio.2023.05.020 -
Archives of Environmental Contamination... Feb 2024Peatlands are found on all continents, covering 3% of the global land area. However, the spatial extent and causes of metal enrichment in peatlands is understudied and...
Peatlands are found on all continents, covering 3% of the global land area. However, the spatial extent and causes of metal enrichment in peatlands is understudied and no attempt has been made to evaluate global patterns of metal enrichment in bog and fen peatlands, despite that certain metals and rare earth elements (REE) arise from anthropogenic sources. We analyzed 368 peat cores sampled in 16 countries across five continents and measured metal and other element concentrations at three depths down to 70 cm as well as estimated cumulative atmospheric S deposition (1850-2009) for each site. Sites were assigned to one of three distinct broadly recognized peatland categories (bog, poor fen, and intermediate-to-moderately rich fen) that varied primarily along a pH gradient. Metal concentrations differed among peatland types, with intermediate-to-moderately rich fens demonstrating the highest concentrations of most metals. Median enrichment factors (EFs; a metric comparing natural and anthropogenic metal deposition) for individual metals were similar among bogs and fens (all groups), with metals likely to be influenced by anthropogenic sources (As, Cd, Co, Cu, Hg, Pb, and Sb) demonstrating median enrichment factors (EFs) > 1.5. Additionally, mean EFs were substantially higher than median values, and the positive correlation (< 0.40) with estimated cumulative atmospheric S deposition, confirmed some level of anthropogenic influence of all pollutant metals except for Hg that was unrelated to S deposition. Contrary to expectations, high EFs were not restricted to pollutant metals, with Mn, K and Rb all exhibiting elevated median EFs that were in the same range as pollutant metals likely due to peatland biogeochemical processes leading to enrichment of these nutrients in surface soil horizons. The global patterns of metal enrichment in bogs and fens identified in this study underscore the importance of these peatlands as environmental archives of metal deposition, but also illustrates that biogeochemical processes can enrich metals in surface peat and EFs alone do not necessarily indicate atmospheric contamination.
Topics: Wetlands; Metals; Mercury; Soil; Environmental Pollutants
PubMed: 38340164
DOI: 10.1007/s00244-024-01051-3 -
International Journal of Pharmaceutics Jul 2023Nanometal-organic frameworks (NMOFs) are porous network structures composed of metal ions or metal clusters through self-assembly. NMOFs have been considered as a... (Review)
Review
Nanometal-organic frameworks (NMOFs) are porous network structures composed of metal ions or metal clusters through self-assembly. NMOFs have been considered as a promising nano-drug delivery system due to their unique properties such as pore and flexible structures, large specific surface areas, surface modifiability, non-toxic and degradable properties. However, NMOFs face a series complex environment during in vivo delivery. Therefore, surface functionalization of NMOFs is vital to ensure that the structure of NMOFs remain stable during delivery, and can overcome physiological barriers to deliver drugs more accurately to specific sites, and achieve controllable release. In this review, the first part summarizes the physiological barriers that NMOFs faced during drug delivery after intravenous injection and oral administration. The second part summarizes the current main ways to load drugs into NMOFs, mainly including pore adsorption, surface attachment, formation of covalent/coordination bonds between drug molecules and NMOFs, and in situ encapsulation. The third part is the main review part of this paper, which summarizes the surface modification methods of NMOFs used in recent years to overcome the physiological barriers and achieve effective drug delivery and disease therapy, which are mainly divided into physical modifications and chemical modifications. Finally, the full text is summarized and prospected, with the hope to provide ideas for the future development of NMOFs as drug delivery.
Topics: Drug Delivery Systems; Metals
PubMed: 37302666
DOI: 10.1016/j.ijpharm.2023.123119 -
Chemosphere Dec 2023The rapid consumption of metals and unorganized disposal have led to unprecedented increases in heavy metal ion concentrations in the ecosystem, which disrupts... (Review)
Review
The rapid consumption of metals and unorganized disposal have led to unprecedented increases in heavy metal ion concentrations in the ecosystem, which disrupts environmental homeostasis and results in agricultural biodiversity loss. Mitigation and remediation plans for heavy metal pollution are largely dependent on the discovery of cost-effective, biocompatible, specific, and robust detectors because conventional methods involve sophisticated electronics and sample preparation procedures. Carbon dots (CDs) have gained significant importance in sensing applications related to environmental sustainability. Fluorescence sensor applications have been enhanced by their distinctive spectral properties and the potential for developing efficient photonic devices. With the recent development of biomass-functionalized carbon dots, a wide spectrum of multivalent and bivalent transition metal ions responsible for water quality degradation can be detected with high efficiency and minimal toxicity. This review explores the various methods of manufacturing carbon dots and the biochemical mechanisms involved in metal detection using green carbon dots for sensing applications involving Cu (II), Fe (III), Hg (II), and Cr (VI) ions in aqueous systems. A detailed discussion of practical challenges and future recommendations is presented to identify feasible design routes.
Topics: Carbon; Biomass; Ecosystem; Quantum Dots; Metals, Heavy; Ions
PubMed: 37871875
DOI: 10.1016/j.chemosphere.2023.140471 -
Environmental Science and Pollution... Aug 2023NO, SO, and carbonaceous volatile organic compounds (VOCs) are extremely harmful to the environment, and their concentrations must be within the limits prescribed by the... (Review)
Review
NO, SO, and carbonaceous volatile organic compounds (VOCs) are extremely harmful to the environment, and their concentrations must be within the limits prescribed by the region-specific pollution control boards. Thus, NO, SO, and VOC abatement is essential to safeguard the environment. Considering the importance of NO, SO, and VOC abatement, the discussion on selective catalytic reduction, oxidation, redox methods, and adsorption using noble metal and non-noble metal-based catalytic approaches were elaborated. This article covers different thermal treatment techniques, category of materials as catalysts, and its structure-property insights along with the advanced oxidation processes and adsorption. The defect engineered catalysts with lattice oxygen vacancies, bi- and tri-metallic noble metal catalysts and non-noble metal catalysts, modified metal organic frameworks, mixed-metal oxide supports, and their mechanisms have been thoroughly reviewed. The main hurdles and potential achievements in developing novel simultaneous NO, SO, and VOC removal technologies are critically discussed to envisage the future directions. This review highlights the removal of NO, SO, and VOC through material selection, properties, and mechanisms to further improve the existing abatement methods in an efficient way.
Topics: Volatile Organic Compounds; Oxidation-Reduction; Oxides; Metals; Oxygen; Catalysis
PubMed: 37495811
DOI: 10.1007/s11356-023-28840-y -
Journal of the American Chemical Society Jul 2023We report a new computational protein design method for the construction of oligomeric protein assemblies around metal centers with predefined coordination geometries....
We report a new computational protein design method for the construction of oligomeric protein assemblies around metal centers with predefined coordination geometries. We apply this method to design two homotrimeric assemblies, Tet4 and TP1, with tetrahedral and trigonal-pyramidal tris(histidine) metal coordination geometries, respectively, and demonstrate that both assemblies form the targeted metal centers with ≤0.2 Å accuracy. Although Tet4 and TP1 are constructed from the same parent protein building block, they are distinct in terms of their overall architectures, the environment surrounding the metal centers, and their metal-based reactivities, illustrating the versatility of our approach.
Topics: Metalloproteins; Metals; Histidine
PubMed: 37352018
DOI: 10.1021/jacs.3c04047