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Antioxidants (Basel, Switzerland) Jul 2023Altered levels of heavy metals and essential elements have been associated with oxidative stress (OS) and metabolic and hormonal changes in women with polycystic ovary... (Review)
Review
Altered levels of heavy metals and essential elements have been associated with oxidative stress (OS) and metabolic and hormonal changes in women with polycystic ovary syndrome (PCOS). We aimed to summarize the knowledge on the association of heavy metals and essential elements with OS in PCOS. An electronic literature search using PubMed for studies published between January 2008 and April 2023 was conducted. We evaluated heavy metals and essential elements in relation to OS in PCOS in 15 articles. PCOS women had increased antimonium (Sb), cadmium (Cd), lead (Pb), mercury (Hg), arsenic (As), tellurium (Te), thallium (Tl) and osmium (Os) blood levels and decreased zinc (Zn) blood levels; the results of copper (Cu) blood levels were conflicting. Some studies showed a significant correlation between heavy metals (Sb, Cd, Pb, Hg, As, Te and Tl) and essential elements (Se, Zn, Cr, Ca, Mg and Cu) and markers of OS and chronic inflammation. Heavy metals (Sb, Cd, Pb and Hg) and essential elements (Zn, Cr, Se, Ca, Mg and Cu) were associated with metabolic and hormonal characteristics in PCOS. There might be a possible benefit from supplementation therapy in reducing OS and endocrinological problems related to PCOS. Our review confirmed an association between heavy metals and essential elements with OS in PCOS women. This systematic review is registered in PROSPERO under number CRD42023418453.
PubMed: 37507937
DOI: 10.3390/antiox12071398 -
BioRxiv : the Preprint Server For... Sep 2023Mapping the complete synaptic connectivity of a mammalian brain would be transformative, revealing the pathways underlying perception, behavior, and memory. Serial...
Mapping the complete synaptic connectivity of a mammalian brain would be transformative, revealing the pathways underlying perception, behavior, and memory. Serial section electron microscopy, via membrane staining using osmium tetroxide, is ideal for visualizing cells and synaptic connections but, in whole brain samples, faces significant challenges related to chemical treatment and volume changes. These issues can adversely affect both the ultrastructural quality and macroscopic tissue integrity. By leveraging time-lapse X-ray imaging and brain proxies, we have developed a 12-step protocol, ODeCO, that effectively infiltrates osmium throughout an entire mouse brain while preserving ultrastructure without any cracks or fragmentation, a necessary prerequisite for constructing the first comprehensive mouse brain connectome.
PubMed: 37808722
DOI: 10.1101/2023.09.26.558265 -
Biomedicine & Pharmacotherapy =... Feb 2024Research into cancer therapeutics has uncovered various potential medications based on metal-containing scaffolds after the discovery and clinical applications of... (Review)
Review
Research into cancer therapeutics has uncovered various potential medications based on metal-containing scaffolds after the discovery and clinical applications of cisplatin as an anti-cancer agent. This has resulted in many metallodrugs that can be put into medical applications. These metallodrugs have a wider variety of functions and mechanisms of action than pure organic molecules. Although platinum-based medicines are very efficient anti-cancer agents, they are often accompanied by significant side effects and toxicity and are limited by resistance. Some of the most studied and developed alternatives to platinum-based anti-cancer medications include metallodrugs based on ruthenium, gold, copper, iridium, and osmium, which showed effectiveness against many cancer cell lines. These metal-based medicines represent an exciting new category of potential cancer treatments and sparked a renewed interest in the search for effective anti-cancer therapies. Despite the widespread development of metal complexes touted as powerful and promising in vitro anti-cancer therapeutics, only a small percentage of these compounds have shown their worth in vivo models. Metallodrugs, which are more effective and less toxic than platinum-based drugs and can treat drug-resistant cancer cells, are the focus of this review. Here, we highlighted some of the most recently developed Pt, Ru, Au, Cu, Ir, and Os complexes that have shown significant in vivo antitumor properties between 2017 and 2023.
Topics: Humans; Coordination Complexes; Neoplasms; Antineoplastic Agents; Cisplatin; Platinum
PubMed: 38290253
DOI: 10.1016/j.biopha.2024.116211 -
Molecules (Basel, Switzerland) Feb 2024A series of new chelating bidentate (SS) alkylimidazole-2-thione-Ru(II)/Os(II) complexes (, , , /, , ), and the tridentate (SNS)...
A series of new chelating bidentate (SS) alkylimidazole-2-thione-Ru(II)/Os(II) complexes (, , , /, , ), and the tridentate (SNS) pyridine-2,6-diylimidazole-2-thione-Ru(II)/Os(II) complexes (, /, , ) in the forms [M(cym)(L)Cl]PF and [M(cym)(L)]PF (M = Ru or Os, cym = η--cymene, and L = heterocyclic derivatives of thiourea) respectively, were successfully synthesized. Spectroscopic and analytical methods were used to characterize the complexes and their ligands. Solid-state single-crystal X-ray diffraction analyses revealed a "piano-stool" geometry around the Ru(II) or Os(II) centers in the respective complexes. The complexes were investigated for in vitro chemotherapeutic activities against human cervical carcinoma (HeLa) and the non-cancerous cell line (Hek293) using the MTT assay. The compounds , , , , , , and the reference drug, 5-fluorouracil were found to be selective toward the tumor cells; the compounds , , , , , and , which were found not to be selective between normal and tumor cell lines. The IC value of the tridentate half-sandwich complex (86 ± 9 μM) showed comparable anti-proliferative activity with the referenced commercial anti-cancer drug, 5-fluorouracil (87 ± 15 μM). The pincer (SNS) osmium complexes (36 ± 10 μM) and (40 ± 4 μM) were twice as effective as the reference drug 5-fluorouracil at the respective dose concentrations. However, the analogous pincer (SNS) ruthenium complex was ineffective and did not show anti-proliferative activity, even at a higher concentration of 147 ± 1 μM. These findings imply that the higher stability of the chelating (SS) and the pincer (SNS) ligand architectures in the complexes improves the biological (anti-proliferative) activity of the complexes by reducing the chance of ligand dissociation under physiological conditions. In general, the pincer (SNS) osmium complexes were found to be more cytotoxic than their ruthenium analogues, suggesting that the anti-proliferative activity of the imidazole-2-thione-Ru/Os complexes depends on the ligand's spatial coordination, the nature of the metal center, and the charge of the metal complex ions.
Topics: Humans; Ruthenium; Osmium; Ligands; HEK293 Cells; Thiones; Chelating Agents; Antineoplastic Agents; Coordination Complexes; Cell Line, Tumor; Fluorouracil; Cymenes
PubMed: 38474456
DOI: 10.3390/molecules29050944 -
Data in Brief Dec 2023This paper presents a dataset offering profound insights into the formation and physical properties of two-dimensional (2D) noble metals under various configurations,...
This paper presents a dataset offering profound insights into the formation and physical properties of two-dimensional (2D) noble metals under various configurations, with a primary focus on their role as catalysts for the hydrogen evolution reaction (HER). These data are of significant value to catalysis researchers, materials scientists, and computational chemists, providing them with a detailed understanding of 2D noble metals' behavior as catalysts and enabling advancements in their respective studies. The dataset, thoughtfully structured and meticulously documented, comprises five primary sections, each housing distinct content and analyses. It offers a comprehensive view of the substrate-mediated stabilization and physical properties of 2D noble metals, including silver (Ag), gold (Au), iridium (Ir), osmium (Os), palladium (Pd), platinum (Pt), rhodium (Rh), and ruthenium (Ru). The substrates utilized include bare Si-face 4H-SiC, buffer layer (BuL), and monolayer epitaxial graphene (MEG). The data collection process involves the use of the SIESTA code for density functional theory (DFT) calculations. The vdW-BH functional is consistently applied in conjunction with a double-ζ polarized (DZP) basis set, known for its reliability in capturing nuanced interactions with noble metals. Parameters such as an energy shift of 200 meV and a force tolerance of 0.02 eV/Å are meticulously configured for accurate results. In-depth structural information, including optimized structures in top and side views and Cartesian coordinates for various substrate-metal configurations, is a central component of the dataset. These structural details are pivotal for comprehending the physical properties of 2D noble metals. Furthermore, the dataset encompasses results from charge density difference (CDD) analyses, including cube files, planar-averaged CDD curves, and 3D CDD maps. These analyses provide essential data for understanding the electronic properties of these materials. The dataset also includes outcomes from charge population analyses utilizing Hirshfeld and Voronoi schemes. These analyses offer insights into structural parameters, Hirshfeld charge magnitudes on 2D metal layers, and various energy-related metrics, further enhancing the dataset's richness. In addition to structural data, the dataset presents atomic structures in top and side views of free-standing and substrate-supported 2D noble metals after hydrogen adsorption, along with corresponding Cartesian coordinates. Gibbs free energy (Δ) data for hydrogen adsorption on both free-standing and substrate-supported 2D noble metals contribute to the dataset's depth. This meticulously curated dataset not only serves as a valuable resource for researchers exploring the properties and behaviors of 2D noble metals but also holds significant reuse potential. Researchers can employ this dataset to validate their computational methods and models in catalysis research, enhancing the quality and reliability of their simulations. Furthermore, it serves as a possible educational tool, fostering hands-on learning for students and emerging researchers in the field of computational materials science and catalysis, thereby promoting methodological consistency within the scientific community.
PubMed: 38053595
DOI: 10.1016/j.dib.2023.109801 -
ACS Organic & Inorganic Au Oct 2023The influence of fluorinated substituents on the luminescent properties of rhenium-oxo, osmium-nitrido, and gold triarylcorroles was studied via a comparison of four...
The influence of fluorinated substituents on the luminescent properties of rhenium-oxo, osmium-nitrido, and gold triarylcorroles was studied via a comparison of four ligands: triphenylcorrole (TPC), tris(-trifluoromethylphenyl)corrole (TCFPC), tris{3,5-bis(trifluoromethyl)phenyl}corrole (T3,5-CFPC), and tris(pentafluorophenyl)corrole (TPFPC). For each metal series examined, fluorinated substituents were found to enhance the luminescent properties, with the phosphorescence quantum yields and triplet decay times increasing in the order TPC < TCFPC < T3,5-CFPC < TPFPC. Among the 11 complexes examined, the highest phosphorescence quantum yield, 2.2%, was recorded for Re[TPFPC](O).
PubMed: 37810408
DOI: 10.1021/acsorginorgau.3c00016 -
FLEX: genetically encodable enzymatic fluorescence signal amplification using engineered peroxidase.Cell Chemical Biology Mar 2024Fluorescent tagging of biomolecules enables their sensitive detection during separation and determining their subcellular location. In this context, peroxidase-based...
Fluorescent tagging of biomolecules enables their sensitive detection during separation and determining their subcellular location. In this context, peroxidase-based reactions are actively utilized for signal amplification. To harness this potential, we developed a genetically encodable enzymatic fluorescence signal amplification method using APEX (FLEX). We synthesized a fluorescent probe, Jenfluor triazole (JFT1), which effectively amplifies and restricts fluorescence signals under fixed conditions, enabling fluorescence-based detection of subcellularly localized electron-rich metabolites. Moreover, JFT1 exhibited stable fluorescence signals even under osmium-treated and polymer-embedded conditions, which supported findings from correlative light and electron microscopy (CLEM) using APEX. Using various APEX-conjugated proteins of interest (POIs) targeted to different organelles, we successfully visualized their localization through FLEX imaging while effectively preserving organelle ultrastructures. FLEX provides insights into dynamic lysosome-mitochondria interactions upon exposure to chemical stressors. Overall, FLEX holds significant promise as a sensitive and versatile system for fluorescently detecting APEX2-POIs in multiscale biological samples.
PubMed: 38513646
DOI: 10.1016/j.chembiol.2024.02.007 -
Heliyon Jun 2023In-resin CLEM (Correlative Light and Electron Microscopy) of Epon-embedded cells involves correlating fluorescence microscopy with electron microscopy in the same...
In-resin CLEM (Correlative Light and Electron Microscopy) of Epon-embedded cells involves correlating fluorescence microscopy with electron microscopy in the same Epon-embedded ultrathin section. This method offers the advantage of high positional accuracy compared to standard CLEM. However, it requires the expression of recombinant proteins. In order to detect the localization of endogenous target(s) and their localized ultrastructures of Epon-embedded samples using in-resin CLEM, we investigated whether immunological and affinity-labeling using fluorescent dyes applied to in-resin CLEM of Epon-embedded cells. The orange fluorescent (λ ∼550 nm) and far-red (λ ∼650 nm) fluorescent dyes examined maintained a sufficient level of fluorescent intensity after staining with osmium tetroxide and subsequent dehydration treatment with ethanol. Immunological in-resin CLEM of mitochondria and the Golgi apparatus was achieved using anti-TOM20, anti-GM130 antibodies, and fluorescent dyes. Two-color in-resin CLEM revealed that wheat germ agglutinin-puncta showed the ultrastructures of multivesicular body-like structures. Finally, taking the advantage of high positional accuracy, volume in-resin CLEM of mitochondria in the semi-thin section (2 μm thick) of Epon-embedded cells was performed by focused ion beam scanning electron microscopy. These results suggested that the application of immunological reaction and affinity-labeling with fluorescent dyes to in-resin CLEM of Epon-embedded cells is suitable for analyzing the localization of endogenous targets and their ultrastructures by scanning and transmission electron microscopy.
PubMed: 37389060
DOI: 10.1016/j.heliyon.2023.e17394 -
Bioelectrochemistry (Amsterdam,... Oct 2023We investigated the bioelectrochemical properties of an FAD-dependent glucose dehydrogenase from Trichoderma virens (TvGDH) and its electrochemical behaviour when...
We investigated the bioelectrochemical properties of an FAD-dependent glucose dehydrogenase from Trichoderma virens (TvGDH) and its electrochemical behaviour when immobilized on a graphite electrode. TvGDH was recently shown to have an unusual substrate spectrum and to prefer maltose over glucose as substrate, and hence could be of interest as recognition element in a maltose sensor. In this study, we determined the redox potential of TvGDH, which is -0.268 ± 0.007 V vs. SHE, and advantageously low to be used with many redox mediators or redox polymers. The enzyme was entrapped in, and wired by an osmium redox polymer (poly(1-vinylimidazole-co-allylamine)-{[Os(2,2'-bipyridine)Cl]Cl}) with formal redox potential of +0.275 V vs. Ag|AgCl via poly(ethylene glycol) diglycidyl ether crosslinking onto a graphite electrode. When the TvGDH-based biosensor was tested with maltose it showed a sensitivity of 1.7 μA mMcm, a linear range of 0.5-15 mM, and a detection limit of 0.45 mM. Furthermore, it gave the lowest apparent Michaelis-Menten constant (K) of 19.2 ± 1.5 mM towards maltose when compared to other sugars. The biosensor is also able to detect other saccharides including glucose, maltotriose and galactose, these however also interfere with maltose sensing.
Topics: Glucose 1-Dehydrogenase; Hypocrea; Graphite; Maltose; Glucose; Biosensing Techniques; Electrodes; Oxidation-Reduction; Polymers; Enzymes, Immobilized
PubMed: 37269684
DOI: 10.1016/j.bioelechem.2023.108480 -
Ecology and Evolution Apr 2024Comparative anatomy is an important tool for investigating evolutionary relationships among species, but the lack of scalable imaging tools and stains for rapidly...
Comparative anatomy is an important tool for investigating evolutionary relationships among species, but the lack of scalable imaging tools and stains for rapidly mapping the microscale anatomies of related species poses a major impediment to using comparative anatomy approaches for identifying evolutionary adaptations. We describe a method using synchrotron source micro-x-ray computed tomography (syn-μXCT) combined with machine learning algorithms for high-throughput imaging of Lepidoptera (i.e., butterfly and moth) eyes. Our pipeline allows for imaging at rates of ~15 min/mm at 600 nm resolution. Image contrast is generated using standard electron microscopy labeling approaches (e.g., osmium tetroxide) that unbiasedly labels all cellular membranes in a species-independent manner thus removing any barrier to imaging any species of interest. To demonstrate the power of the method, we analyzed the 3D morphologies of butterfly crystalline cones, a part of the visual system associated with acuity and sensitivity and found significant variation within six butterfly individuals. Despite this variation, a classic measure of optimization, the ratio of interommatidial angle to resolving power of ommatidia, largely agrees with early work on eye geometry across species. We show that this method can successfully be used to determine compound eye organization and crystalline cone morphology. Our novel pipeline provides for fast, scalable visualization and analysis of eye anatomies that can be applied to any arthropod species, enabling new questions about evolutionary adaptations of compound eyes and beyond.
PubMed: 38571794
DOI: 10.1002/ece3.11137