-
Handbook of Clinical Neurology 2017Wilson disease is an autosomal-recessive copper overload disorder causing hepatic and neurologic symptoms. Commonly used medical therapy shows satisfactory results with... (Review)
Review
Wilson disease is an autosomal-recessive copper overload disorder causing hepatic and neurologic symptoms. Commonly used medical therapy shows satisfactory results with regard to hepatic disease but only limited effects in neurologically affected patients. In recent years several new therapy options have been developed, showing promising results that might improve the management of Wilson disease in the near future. Optimization of treatment regimens depending on biochemical response pattern seems worthwhile, especially in the decoppering phase of therapy. The chelator tetrathiomolybdate (TTM) is a promising therapy option, currently under clinical investigation. TTM is a fast-acting and very potent chelator and appears to be associated with early neurologic deterioration after initiation of therapy to a lower extent than the drugs currently used. Treatment with nonchelating drugs characterized by alternative modes of action is under investigation, but restricted to animal or in vitro studies to date. This includes basic research studies demonstrating proof of principle for successful cell or gene therapy in Wilson disease in order to restore sufficient biliary copper excretion, even before the onset of disease.
Topics: Animals; Chelating Agents; Copper; Genetic Therapy; Hepatolenticular Degeneration; Humans; Molybdenum
PubMed: 28433106
DOI: 10.1016/B978-0-444-63625-6.00019-7 -
Environmental Health and Preventive... May 2019Melanin is detectable in various sense organs including the skin in animals. It has been reported that melanin adsorbs toxic elements such as mercury, cadmium, and lead....
BACKGROUND
Melanin is detectable in various sense organs including the skin in animals. It has been reported that melanin adsorbs toxic elements such as mercury, cadmium, and lead. In this study, we investigated the adsorption of molybdenum, which is widely recognized as a toxic element, by melanin.
METHODS
Molybdenum level of the mouse skin was measured by inductively coupled plasma mass spectrometry. The pigmentation level of murine skin was digitalized as the L* value by using a reflectance spectrophotometer. An in vitro adsorption assay was performed to confirm the interaction between molybdenum and melanin.
RESULTS
Our analysis of hairless mice with different levels of skin pigmentation showed that the level of molybdenum increased with an increase in the level of skin pigmentation (L* value). Moreover, our analysis by Spearman's correlation coefficient test showed a strong correlation (r = - 0.9441, p < 0.0001) between L* value and molybdenum level. Our cell-free experiment using the Langmuir isotherm provided evidence for the adsorption of molybdenum by melanin. The maximum adsorption capacity of 1 mg of synthetic melanin for molybdenum was 131 μg in theory.
CONCLUSION
Our in vivo and in vitro results showed a new aspect of melanin as an adsorbent of molybdenum.
Topics: Adsorption; Animals; Melanins; Mice; Mice, Hairless; Mice, Transgenic; Molybdenum; Skin; Skin Pigmentation; Water Pollutants, Chemical
PubMed: 31101002
DOI: 10.1186/s12199-019-0791-y -
Small (Weinheim An Der Bergstrasse,... Aug 2022The disulfide compounds of molybdenum (MoS ) are layered van der Waals materials that exhibit a rich array of polymorphic structures. MoS can be roughly divided into... (Review)
Review
The disulfide compounds of molybdenum (MoS ) are layered van der Waals materials that exhibit a rich array of polymorphic structures. MoS can be roughly divided into semiconductive phase and metallic phase according to the difference in electron filling state of the 4d orbital of Mo atom. The two phases show completely different properties, leading to their diverse applications in biosensors. But to some extent, they compensate for each other. This review first introduces the relationship between phase state and the chemical/physical structures and properties of MoS . Furthermore, the synthetic methods are summarized and the preparation strategies for metastable phases are highlighted. In addition, examples of electronic and chemical property designs of MoS by means of doping and surface modification are outlined. Finally, studies on biosensors based on MoS in recent years are presented and classified, and the roles of MoS with different phases are highlighted. This review offers references for the selection of materials to construct different types of biosensors based on MoS , and provides inspiration for sensing performance enhancement.
Topics: Biosensing Techniques; Disulfides; Molybdenum
PubMed: 35908166
DOI: 10.1002/smll.202202956 -
Journal of Materials Chemistry. B Apr 2022Molybdenum disulfide (MoS) nanostructures have recently earned substantial thoughts from the scientific communities owing to their unique physicochemical, optical and... (Review)
Review
Molybdenum disulfide (MoS) nanostructures have recently earned substantial thoughts from the scientific communities owing to their unique physicochemical, optical and electrical properties. Although MoS has been mostly highlighted for its industrial applications, its biological applicability has not been extensively explored. The introduction of nanotechnology in the field of tissue engineering has significantly contributed to human welfare by displaying advancement in tissue regeneration. Assimilation of MoS nanostructures into the polymer matrix has been considered a persuasive material of choice for futuristic tissue engineering applications. The current review provides a general discussion on the structural properties of different MoS nanostructures. Further, this article focuses on the interactions of MoS with biological systems in terms of its cellular toxicity, and biocompatibility along with its capability for cell proliferation, adhesion, and immunomodulation. The article continues to confer the utility of MoS nanostructure-based scaffolds for various tissue engineering applications. The article also highlights some emerging prospects and possibilities of the applicability of MoS-based nanostructures in large organ tissue engineering. Finally, the article concludes with a brief annotation on the challenges and limitations that need to be overcome in order to make plentiful use of this wonderful material for tissue engineering applications.
Topics: Disulfides; Humans; Molybdenum; Nanostructures; Tissue Engineering
PubMed: 35262167
DOI: 10.1039/d2tb00131d -
The Journal of Biological Chemistry Mar 2022Sulfite oxidase (SOX) is a homodimeric molybdoheme enzyme that oxidizes sulfite to sulfate at the molybdenum center. Following substrate oxidation, molybdenum is reduced...
Sulfite oxidase (SOX) is a homodimeric molybdoheme enzyme that oxidizes sulfite to sulfate at the molybdenum center. Following substrate oxidation, molybdenum is reduced and subsequently regenerated by two sequential electron transfers (ETs) via heme to cytochrome c. SOX harbors both metals in spatially separated domains within each subunit, suggesting that domain movement is necessary to allow intramolecular ET. To address whether one subunit in a SOX dimer is sufficient for catalysis, we produced heterodimeric SOX variants with abolished sulfite oxidation by replacing the molybdenum-coordinating and essential cysteine in the active site. To further elucidate whether electrons can bifurcate between subunits, we truncated one or both subunits by deleting the heme domain. We generated three SOX heterodimers: (i) SOX/Mo with two active molybdenum centers but one deleted heme domain, (ii) SOX/Mo_C264S with one unmodified and one inactive subunit, and (iii) SOX_C264S/Mo harboring a functional molybdenum center on one subunit and a heme domain on the other subunit. Steady-state kinetics showed 50% SOX activity for the SOX/Mo and SOX/Mo_C264S heterodimers, whereas SOX_C264S/Mo activity was reduced by two orders of magnitude. Rapid reaction kinetics monitoring revealed comparable ET rates in SOX/Mo, SOX/Mo_C264S, and SOX/SOX, whereas in SOX_C264S/Mo, ET was strongly compromised. We also combined a functional SOX Mo domain with an inactive full-length SOX R217W variant and demonstrated interdimer ET that resembled SOX_C264S/Mo activity. Collectively, our results indicate that one functional subunit in SOX is sufficient for catalysis and that electrons derived from either Mo or Mo follow this path.
Topics: Electrons; Heme; Molybdenum; Protein Domains; Sulfite Oxidase; Sulfites
PubMed: 35120924
DOI: 10.1016/j.jbc.2022.101668 -
Acta Biomaterialia Apr 2024Cardiac pacing with temporary epicardial pacing wires (TEPW) is used to treat rhythm disturbances after cardiac surgery. Occasionally, TEPW cannot be mechanically...
Cardiac pacing with temporary epicardial pacing wires (TEPW) is used to treat rhythm disturbances after cardiac surgery. Occasionally, TEPW cannot be mechanically extracted and remain in the thorax, where they may rarely cause serious complications like migration and infection. We aim to develop bioresorbable TEPW that will dissolve over time even if postoperative removal is unsuccessful. In the present study, we demonstrate a completely bioresorbable design using molybdenum (Mo) as electric conductor and the resorbable polymers poly(D, L-lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL) for electrically insulating double-coating. We compared the pacing properties of these Mo TEPW demonstrators to conventional steel TEPW in Langendorff-perfused rat hearts and observed similar functionality. In vitro, static immersion tests in simulated body fluid for up to 28 days elucidated the degradation behaviour of uncoated Mo strands and the influence of polymer coating thereon. Degradation was considerably reduced in double-coated Mo TEPW compared to the uncoated and the PLGA-coated condition. Furthermore, we confirmed good biocompatibility of Mo degradation products in the form of low cytotoxicity in cell cultures of human cardiomyocytes and cardiac fibroblasts. STATEMENT OF SIGNIFICANCE: Temporary pacing wires are routinely implanted on the heart surface to treat rhythm disturbances in the days following cardiac surgery. Subsequently, these wires are to be removed. When removal attempts are unsuccessful, wires are cut at skin level and the remainders are left inside the chest. Retained fragments may migrate within the body or become a centre of infection. These complications may be prevented using resorbable pacing wires. We manufactured completely resorbable temporary pacing wires using molybdenum as electrical conductor and assessed their function, degradation and biological compatibility. Our study represents an important step in the development of a safer approach to the treatment of rhythm disturbances after cardiac surgery.
Topics: Humans; Animals; Rats; Cardiac Pacing, Artificial; Pacemaker, Artificial; Molybdenum; Absorbable Implants; Pericardium
PubMed: 38432350
DOI: 10.1016/j.actbio.2024.02.039 -
Nanotoxicology Feb 2021Understanding the roles of the properties of nanomaterials in biological interactions is a key issue in their safe applications, but the surface atomic arrangement, as...
Understanding the roles of the properties of nanomaterials in biological interactions is a key issue in their safe applications, but the surface atomic arrangement, as an important property of engineered nanomaterials (ENMs), remains largely unknown. Herein, the interfacial interactions (affinity sites and intensity) between monolayer MoS and zebrafish embryos mediated by 1 T phase surface atomic arrangement (octahedral coordination) and the 2H phase surface atomic arrangement (triangular prism coordination) MoS nanosheets were studied. 1 T-MoS first bound to phosphate and then proteins on the chorion, while the adhesion of 2H-MoS occurred in the opposite order. The binding affinity of 2H-MoS with embryos was higher than that of 1 T-MoS, and the former material changed the protein structure from β-sheets to turns and bends and random coils. Compared to 1 T-MoS, 2H-MoS more readily entered embryos, which was facilitated by caveolae-mediated endocytosis, and caused higher developmental toxicity. Furthermore, metabolic pathways related to amino acid and protein biosynthesis and energy metabolism were affected by the nanomaterial surface atomic arrangements. The above results provide insights into the designs, applications and risk assessments of nanomaterials by the surface atomic arrangement regulation.
Topics: Animals; Chorion; Disulfides; Embryo, Nonmammalian; Endocytosis; Metabolic Networks and Pathways; Molybdenum; Nanostructures; Zebrafish
PubMed: 33206573
DOI: 10.1080/17435390.2020.1844915 -
Angewandte Chemie (International Ed. in... Oct 2022The biological process of dinitrogen reduction to ammonium occurs at the cofactors of nitrogenases, the only enzymes that catalyze this challenging chemical reaction....
The biological process of dinitrogen reduction to ammonium occurs at the cofactors of nitrogenases, the only enzymes that catalyze this challenging chemical reaction. Three types of nitrogenases have been described, named according to the heterometal in their cofactor: molybdenum, vanadium or iron nitrogenases. Spectroscopic and structural characterization allowed the unambiguous identification of the cofactors of molybdenum and vanadium nitrogenases and revealed a central μ -carbide in both of them. Although genetic studies suggested that the cofactor of the iron nitrogenase contains a similar Fe C core, this has not been experimentally demonstrated. Here we report Valence-to-Core X-ray Emission Spectroscopy providing experimental evidence that this cofactor contains a carbide, thereby making the Fe C core a feature of all nitrogenase cofactors.
Topics: Ammonium Compounds; Iron; Molybdenum; Nitrogenase; Oxidation-Reduction; Vanadium
PubMed: 35975943
DOI: 10.1002/anie.202209190 -
Angewandte Chemie (International Ed. in... Mar 2019Polyoxometalates (POMs) are an emerging class of inorganic metal oxides, which over the last decades demonstrated promising biological activities by the virtue of their... (Review)
Review
Polyoxometalates (POMs) are an emerging class of inorganic metal oxides, which over the last decades demonstrated promising biological activities by the virtue of their great diversity in structures and properties. They possess high potential for the inhibition of various tumor types; however, their unspecific interactions with biomolecules and toxicity impede their clinical usage. The current focus of the field of biologically active POMs lies on organically functionalized and POM-based nanocomposite structures as these hybrids show enhanced anticancer activity and significantly reduced toxicity towards normal cells in comparison to unmodified POMs. Although the antitumor activity of POMs is well documented, their mechanisms of action are still not well understood. In this Review, an overview is given of the cytotoxic effects of POMs with a special focus on POM-based hybrid and nanocomposite structures. Furthermore, we aim to provide proposed mode of actions and to identify molecular targets. POMs are expected to develop into the next generation of anticancer drugs that selectively target cancer cells while sparing healthy cells.
Topics: Animals; Antineoplastic Agents; Drug Discovery; Humans; Models, Molecular; Molybdenum; Neoplasms; Niobium; Organometallic Compounds; Tungsten; Tungsten Compounds; Vanadium
PubMed: 29893459
DOI: 10.1002/anie.201803868 -
ACS Applied Materials & Interfaces Mar 2019Flexible, stretchable, and bendable materials, including inorganic semiconductors, organic polymers, graphene, and transition metal dichalcogenides (TMDs), are... (Review)
Review
Flexible, stretchable, and bendable materials, including inorganic semiconductors, organic polymers, graphene, and transition metal dichalcogenides (TMDs), are attracting great attention in such areas as wearable electronics, biomedical technologies, foldable displays, and wearable point-of-care biosensors for healthcare. Among a broad range of layered TMDs, atomically thin layered molybdenum disulfide (MoS) has been of particular interest, due to its exceptional electronic properties, including tunable bandgap and charge carrier mobility. MoS atomic layers can be used as a channel or a gate dielectric for fabricating atomically thin field-effect transistors (FETs) for electronic and optoelectronic devices. This review briefly introduces the processing and spectroscopic characterization of large-area MoS atomically thin layers. The review summarizes the different strategies in enhancing the charge carrier mobility and switching speed of MoS FETs by integrating high-κ dielectrics, encapsulating layers, and other 2D van der Waals layered materials into flexible MoS device structures. The photoluminescence (PL) of MoS atomic layers has, after chemical treatment, been dramatically improved to near-unity quantum yield. Ultraflexible and wearable active-matrix organic light-emitting diode (AM-OLED) displays and wafer-scale flexible resistive random-access memory (RRAM) arrays have been assembled using flexible MoS transistors. The review discusses the overall recent progress made in developing MoS based flexible FETs, OLED displays, nonvolatile memory (NVM) devices, piezoelectric nanogenerators (PNGs), and sensors for wearable electronic and optoelectronic devices. Finally, it outlines the perspectives and tremendous opportunities offered by a large family of atomically thin-layered TMDs.
Topics: Disulfides; Luminescent Measurements; Molybdenum; Nanotechnology; Transistors, Electronic; Wearable Electronic Devices
PubMed: 30830744
DOI: 10.1021/acsami.8b19859