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Comprehensive Summary: Poly‐NHC‐based organometallic assemblies 3‐PF6, 3‐SbF6 and 3‐OTf were obtained and verified by NMR spectroscopy, ESI mass spectrometry and single‐crystal X‐ray diffraction analyses. Controllable structural interconversion was observed between the poly‐NHC‐based organometallic assemblies and their self‐aggregated dimers in solution affected by concentration, solvent and metal ion. 1H NMR spectra of assembly 3‐PF6 in CD3CN at different concentrations demonstrated controllable structural interconversion, and 19F NMR spectrum of assembly 3‐PF6 at high concentration further evidenced the presence of the free hexafluorophosphate anion and encapsulated hexafluorophosphate anion for its two sets of signals. In addition, single‐crystal X‐ray diffraction analysis provided clear evidence that in the solid state, two assemblies 3‐PF6 were vertically stuck, forming a self‐aggregated dimer with an encapsulated hexafluorophosphate anion. Investigating the reversible structural interconversion is beneficial for revealing the intrinsic nature on the atom level and paving the way to design the stimuli‐responsive functional system. [ABSTRACT FROM AUTHOR]

Radiation damage is an inherent problem in macromolecular crystallography because it impairs the diffraction quality of crystals and produces inaccurate structural information. Understanding radiation damage in protein structures is crucial for accurate structural interpretation and effective data collection. This study undertook X-ray data collection and structure determination of thermolysin (TLN), which contains Zn and Ca ions, by using three different X-ray doses to improve our understanding of the radiation damage phenomena on metal ions in proteins. Data processing revealed typical global radiation damage in TLN, such as an increase in unit cell volume, Rmerge value, and Wilson B-factor. An analysis of the B-factor indicated that radiation damage at the Zn and Ca sites in TLN increased with higher X-ray doses. However, the distance between the metal ions and their interacting residues in TLN was not significantly affected, suggesting that radiation damage to the metal ions has a minimal effect on these interactions. Moreover, the increase in the B-factor of the metal ions according to the X-ray dose was similar to that in the B-factor of the residues interacting with the metal ions. These results expand our understanding of radiation damage phenomena in macromolecules and can be used to improve data collection strategies. [ABSTRACT FROM AUTHOR]

Aims: Rotator cuff tear (RCT) is the leading cause of shoulder pain, primarily associated with age-related tendon degeneration. This study aimed to elucidate the potential differential gene expressions in tendons across different age groups, and to investigate their roles in tendon degeneration. Methods: Linear regression and differential expression (DE) analyses were performed on two transcriptome profiling datasets of torn supraspinatus tendons to identify age-related genes. Subsequent functional analyses were conducted on these candidate genes to explore their potential roles in tendon ageing. Additionally, a secondary DE analysis was performed on candidate genes by comparing their expressions between lesioned and normal tendons to explore their correlations with RCTs. Results: We identified 49 genes in torn supraspinatus tendons associated with advancing age. Among them, five age-related genes showed DE in lesioned tendons compared to normal tendons. Functional analyses and previous studies have highlighted their specific enrichments in biological functions, such as muscle development (e.g. myosin heavy chain 3 (MYH3)), transcription regulation (e.g. CCAAT enhancer binding brotein delta (CEBPD)), and metal ion homeostasis (e.g. metallothionein 1X (MT1X)). Conclusion: This study uncovered molecular aspects of tendon ageing and their potential links to RCT development, offering insights for targeted interventions. These findings enhance our understanding of the mechanisms of tendon degeneration, allowing potential strategies to be made for reducing the incidence of RCT. Cite this article: Bone Joint Res 2024;13(9):474–484.

Abstract Ferroptosis is a novel form of programmed cell death caused by damage to lipid membranes due to the accumulation of lipid peroxides in response to various stimuli, such as high levels of iron, oxidative stress, metabolic disturbance, etc. Sugar, lipid, amino acid, and iron metabolism are crucial in regulating ferroptosis. The solute carrier transporters (SLCs) family, known as the “metabolic gating” of cells, is responsible for transporting intracellular nutrients and metabolites. Recent studies have highlighted the significant role of SLCs family members in ferroptosis by controlling the transport of various nutrients. Here, we summarized the function and mechanism of SLCs in ferroptosis regulated by ion, metabolic control of nutrients, and multiple signaling pathways, with a focus on SLC–related transporters that primarily transport five significant components: glucose, amino acid, lipid, trace metal ion, and other ion. Furthermore, the potential clinical applications of targeting SLCs with ferroptosis inducers for various diseases, including tumors, are discussed. Overall, this paper delves into the novel roles of the SLCs family in ferroptosis, aiming to enhance our understanding of the regulatory mechanisms of ferroptosis and identify new therapeutic targets for clinical applications.

Biometal ions are crucial in the structure and function of living organisms and have extensively been employed to promote bone tissue regeneration. Nevertheless, the biological functions of biometal ions and the underlying mechanisms responsible for their pro-regenerative effects remain incompletely understood, since bone repair is an intricate physiological process involving multiple cell types and signals. Recent accomplishments in the osteoimmunological field have revealed the momentous involvement of the immune system in mediating the therapeutic effects of biometal ions. The inflammatory factors secreted by immune cells contribute to bone cell migration, activation, and proliferation. This review summarizes the immune system and its constituent cells, followed by the current perspective on immunomodulation during bone healing. Next, the physicochemical and physiological properties of various biometal ions, including lithium, sodium, potassium, magnesium, calcium, strontium, vanadium, iron, cobalt, copper, and zinc, are thoroughly reviewed. In addition, the interactions between biometal ions, immune cells, and bone tissue are discussed, aiming to provide insights into the prospective development of novel approaches to bone tissue regeneration by harnessing the therapeutic potential of these biometal ions.

The toughening modification of polybenzoxazine is a crucial approach for expanding its application. However, enhancing the toughness of polybenzoxazine poses challenges in concurrently improving comprehensive properties, such as thermal stability, while reducing the curing temperature. To address this issue, we designed a new polyurethane (CIPU) rich in hydrogen bonding and metal coordination bonding and blended it with benzoxazines to tough polybenzoxazine while enhancing their properties across various aspects. Specifically, the addition of 10% CIPU to benzoxazines increased the toughness of polybenzoxazines by 165.3%, attributed to the relative softness of CIPU and multiple sacrificial bonds. Furthermore, the coordination of free In3+ resulted in a significant enhancement in thermal stability and decrement in curing temperature, evidenced by the increase in residual carbon from 30% to 37% at 800 °C and a decrease in the onset of curing temperature from 246.9 °C to 170.7 °C. This work not only introduces a new system for toughening benzoxazine, but also provides unique insights into hydrogen bonding as well as metal-ligand bonding on toughing thermoset resins.

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: In order to better preserve phospholipids (PLs)‐type polyunsaturated fatty acids (PUFAs) and astaxanthin (ASTA), Antarctic krill oil (AKO) undergoes only limited refining steps, which results in the presence of metal ions. This study aims to establish a metal ion removal method for AKO by using adsorbents and investigate the effects of the metal ion removal process on nutritional composition, oxidation state and colour of AKO, as well as the effects of metal oil removal of AKO on its nutrition composition, oxidation stability and colour stability upon accelerated storage. Among the three types of adsorbents including silica gel, diatomaceous earth, and attapulgite soil, the last one showed the best comprehensive removal effects. After optimising the removal conditions, attapulgite soil achieved the removal rates of 92.5%, 90.0%, and 86.4%, respectively, for iron ions, magnesium ions and calcium ions. Compared to the fresh AKO, the processed AKO had no significant differences in peroxide value (POV), thiobarbituric acid reactive substances (TBARS), and total oxidation value (TOTOX), as well as PUFA content and lipid class composition, indicating that the metal ion removal process would not cause significant lipid oxidation. Moreover, the processed AKO looks brighter and more transparent, and had higher detection values in L*, a*, and b* but lower UV‐vis absorption at 295 nm (A295) and 420 nm (A420). This indicated that the metal ion removal process improved the colour quality. After accelerated storage at 60 °C for 8 days, the processed AKO sample had significantly lower values in POV, TBARS, and TOTOX, but significant higher PUFA content than the fresh AKO group. Moreover, the processed AKO sample had the higher values of L*, a*, and b*, as well as A470 and A495, but the lower values of A295 and A420. The above results indicate that the removal of metal ions significantly improved the stabilities of oxidation and colour of AKO. [ABSTRACT FROM AUTHOR]

Ferroptosis is a novel form of programmed cell death caused by damage to lipid membranes due to the accumulation of lipid peroxides in response to various stimuli, such as high levels of iron, oxidative stress, metabolic disturbance, etc. Sugar, lipid, amino acid, and iron metabolism are crucial in regulating ferroptosis. The solute carrier transporters (SLCs) family, known as the "metabolic gating" of cells, is responsible for transporting intracellular nutrients and metabolites. Recent studies have highlighted the significant role of SLCs family members in ferroptosis by controlling the transport of various nutrients. Here, we summarized the function and mechanism of SLCs in ferroptosis regulated by ion, metabolic control of nutrients, and multiple signaling pathways, with a focus on SLC–related transporters that primarily transport five significant components: glucose, amino acid, lipid, trace metal ion, and other ion. Furthermore, the potential clinical applications of targeting SLCs with ferroptosis inducers for various diseases, including tumors, are discussed. Overall, this paper delves into the novel roles of the SLCs family in ferroptosis, aiming to enhance our understanding of the regulatory mechanisms of ferroptosis and identify new therapeutic targets for clinical applications. [ABSTRACT FROM AUTHOR]

Copper is known to have toxic effects on bacterial growth. This study aimed to determine the influence of copper ions on Oleidesulfovibrio alaskensis G20 biofilm formation in a lactate-C medium supplemented with variable copper ion concentrations. OA G20, when grown in media supplemented with high copper ion concentrations of 5, 15, and 30 µM, exhibited inhibited growth in its planktonic state. Conversely, under similar copper concentrations, OA G20 demonstrated enhanced biofilm formation on glass coupons. Microscopic studies revealed that biofilms exposed to copper stress demonstrated a change in cellular morphology and more accumulation of carbohydrates and proteins than controls. Consistent with these findings, sulfur (dsrA, dsrB, sat, aprA) and electron transport (NiFeSe, NiFe, ldh, cyt3) genes, polysaccharide synthesis (poI), and genes involved in stress response (sodB) were significantly upregulated in copper-induced biofilms, while genes (ftsZ, ftsA, ftsQ) related to cellular division were negatively regulated compared to controls. These results indicate that the presence of copper ions triggers alterations in cellular morphology and gene expression levels in OA G20, impacting cell attachment and EPS production. This adaptation, characterized by increased biofilm formation, represents a crucial strategy employed by OA G20 to resist metal ion stress. [ABSTRACT FROM AUTHOR]

A new imidazole‐modified reduced graphene oxide was synthesized through a substitution reaction between amino imidazole and chlorographene. Functional groups and material composition were characterized by using several methods. The N content of product is high, it possesses more ligands. These ligands still combine metal ions under acidic conditions. Adsorption for methylene blue can be fitted by quasi‐second‐order kinetics and Langmuir isotherm model, physical adsorption is the predominant adsorption mechanism. Adsorption capacity (350.7 mg/g) of product for Cr (III) is about fourfold higher than that (74.7 mg/g) of reduced graphene oxide. [ABSTRACT FROM AUTHOR]

BACKGROUND: As a bone replacement and filling material, calcium phosphate stone bone cement has good biocompatibility, bone conductivity, and other advantages, especially its better biodegradability compared to other calcium phosphate bone cements. It has important application value in bone repair. However, due to its limitations such as insufficient mechanical properties, fast solidification reaction, and poor injection performance, it is currently only suitable for the repair of non weight-bearing bone. OBJECTIVE: To explore the modification of brushite cements with bioactive ions (metal and non metal ions) to expand its application range. METHODS: The author used PubMed, ScienceDirect, CNKI, and WanFang to search the literature published between 2018 and 2023 with the search terms “metal ion, iron, copper, strontium, magnesium, zinc, non-metal ion, modification, bone, brushite cements” in Chinese and “metal ion, iron, Fe, copper, Cu, strontium, Sr, magnesium, Mg, zinc, Zn, non-metal ion, modification, bone, brushite cements” in English. After reading titles and abstracts, the articles were initially screened, and irrelevant and duplicate articles were excluded. Finally, 64 articles were included for review. RESULTS AND CONCLUSION: (1) Bioactive ions affect the hydration process of calcium phosphate bone cement. Different ions are substituted by ions and incorporated into the crystal structure of calcium phosphate bone cement, changing the crystal morphology of the cement and causing changes in physical and chemical properties such as setting time, injectability, and compressive strength. (2) Ionic modified calcium phosphate bone cement produces different ion release effects due to different crystal structures. Different types of ions have properties such as promoting angiogenesis/osteogenesis, antibacterial, antitumor, etc. In addition, calcium phosphate bone cement has good biodegradability, which has great advantages for the performance of various ions. (3) The physicochemical properties of calcium phosphate bone cement modified with different ions are as follows: iron, copper, strontium, magnesium, zinc, silver, and cobalt can prolong the setting time. Strontium, and magnesium can improve injection performance. Copper, strontium, magnesium, silver and silicon can enhance compressive strength. The ions that can simultaneously improve the three physical and chemical properties of calcium phosphate bone cement include strontium and magnesium. Good physical and chemical properties are a prerequisite for clinical application, so improving the setting time, injectability, compressive strength, and other properties of calcium phosphate bone cement with ions is of great significance for the research and application of bone cement. (4) The biological properties of calcium phosphate bone cement modified with different ions are as follows: copper, strontium, magnesium, zinc, cobalt, lithium, selenium, and silicon have promoting angiogenesis/osteogenic effects. Iron, copper, magnesium, zinc, and silver have antibacterial properties. Magnesium ions have anti-inflammatory properties. Copper and selenium have anti-tumor properties. (5) In summary, magnesium ions can improve the setting time, injectability, and compressive strength of calcium phosphate bone cement, while also promoting neovascularization/osteogenesis, antibacterial properties, and have good application prospects for the treatment of bone defects with concurrent infections. In addition, copper also has anti-tumor properties, so copper ions have great potential in the treatment of bone defects caused by infections and tumors. However, relevant research is still in the basic research stage, and the effects of different ion doping concentrations and synthesis conditions on the physicochemical properties of calcium phosphate bone cement need to be further explored. At the same time, the impact of biological properties also needs to be studied and observed for a longer period of time. [ABSTRACT FROM AUTHOR]

Glucoraphanin (GRA) produced by the hairy roots of broccoli (Brassica oleracea L. variety Italica Planch) is converted to the secondary metabolite Sulforaphane (SF), which has anticancer properties under specific conditions, and the synthesis of SF is significantly affected by both Ca2+ and Fe2+. Based on the screening of GRA, SF yields, and Epithiospecififier Protein (ESP) activity, the optimal concentration of exogenously added metal ion chelator Ethylene Glycol bis (2-aminoethyl) Tetraacetic Acid (EGTA) for the treatment of broccoli hairy roots and the optimal treatment time were 8.0 mM EGTA for 48 h. Fe2+ content in hairy roots of broccoli reached the lowest level at 48 h, and also significantly reduce the Ca2+ content, but the Ca2+ content recovered with the treatment time and reached the highest level at 48 h. Analysis of transcriptomics data indicated that the physiological and biochemical responses of broccoli hairy roots to exogenous additions of EGTA to metabolic pathways were mainly mediated by the regulation of the expression of relevant genes involved in signal transduction and amino acid metabolism. The expression of NSP2, NSP5, and ESP decreased with the increase of EGTA treatment time and was lowest at 48 h. The expression of 12 genes, such as AOP1.2.7, GSTF11 increased with the increase of EGTA treatment time, and the highest expression was found at 48 h. This study presented a theoretical basis for the study of the exogenous addition of EGTA to alter Ca2+ and Fe2+ contents and affect SF synthesis. [ABSTRACT FROM AUTHOR]

Characteristics of the digestive enzymes of the fifth instar larvae of the beet moth were determined to achieve a superior understanding of the digestive physiology of the pest. After dissecting the larval digestive tube, optimum acidity for the activity of α-amylase and α-glucosidase was obtained 8–9, and 8 for β-glucosidase, respectively. The optimum temperatures were 35 °C and 35–40 °C for α-amylase activity and for α- and β-glucosidase, respectively. The zymogram displayed the existence of three α-amylase isoforms in the digestive tract of this insect. The maximum activity of general protease was determined in the digestive tract of this pest using azocasein substrate in the pH range of 10–11. Furthermore, the optimum temperature was 35 °C for general protease. The metal ions including iron, magnesium, manganese, zinc, and copper at 5 and 10mM concentrations had a significant influence on the activity of α-amylase, α- and β-glucosidase, trypsin, chymotrypsin, and elastase enzymes. Zymogram confirmed the significant inhibitory effect of PMSF and TLCK on the activity of serine proteases, especially trypsin. The results of this research have determined to some extent the digestive system physiology and the digestive enzymes activity range in S. ocellatella. Certainly, Study on the characteristics of digestive enzymes of beet moth can be the starting point for further studies on the use of enzyme inhibitors and the possibility of preparing new methods to control this key sugar beet pest. [ABSTRACT FROM AUTHOR]

Protein lipoylation is critical for the optimal function of several key enzymes in mitochondria; thus, regulating lipoylation greatly impacts mitochondrial function and cell metabolism. As a novel cell death pathway, cuproptosis involves two essential mechanisms: protein lipoylation and copper overload. Recent studies indicate that the ferredoxin 1 (FDX1)/ lipoic acid synthase (LIAS) axis links lipoylation and excessive copper ions and plays a key role in cuproptosis. New techniques suggest there are more potential lipoylated proteins. Given the pivotal role of mitochondria in cell metabolism, targeting protein lipoylation could be a promising strategy for disease therapy. Protein lipoylation, a crucial post-translational modification (PTM), plays a pivotal role in mitochondrial function and emerges as a key player in cell death through cuproptosis. This novel copper-driven cell death pathway is activated by excessive copper ions binding to lipoylated mitochondrial proteins, disrupting energy production and causing lethal protein aggregation and cell death. The intricate relationship among protein lipoylation, cellular energy metabolism, and cuproptosis offers a promising avenue for regulating essential cellular functions. This review focuses on the mechanisms of lipoylation and its significant impact on cell metabolism and cuproptosis, emphasizing the key genes involved and their implications for human diseases. It offers valuable insights into targeting dysregulated cellular metabolism for therapeutic purposes. [ABSTRACT FROM AUTHOR]

In this study adsorption of chromium (VI) ion by using blended natural novel adsorbent like neem leaves powder with peanut shell powder. The batch Adsorption experiments were conducted by different proportions of blended neem leaf powder and peanut shells powder and variations in the weight of adsorbents, contact time at room temperature, and various pH. Investigate the concentration of adsorbate before adsorption and after adsorption by 1, 5 Diphenyl Carbazide Colorimetric method with reference to calibration curve. Results obtained by blended neem leaves powder with peanut shell powder adsorbent are more effective at pH 6. Removal of efficiency increases with increasing contact time and dosage of adsorbent. This adsorbent is low cost and readily available in nature. [ABSTRACT FROM AUTHOR]

Glycans, carbohydrates, and glycoconjugates are involved in many crucial biological processes, such as disease development, immune responses, and cell–cell recognition. Glycans and carbohydrates are known for the large number of isomeric features associated with their structures, making analysis challenging compared with other biomolecules. Mass spectrometry has become the primary method of structural characterization for carbohydrates, glycans, and glycoconjugates. Metal adduction is especially important for the mass spectrometric analysis of carbohydrates and glycans. Metal‐ion adduction to carbohydrates and glycoconjugates affects ion formation and the three‐dimensional, gas‐phase structures. Herein, we discuss how metal‐ion adduction impacts ionization, ion mobility, ion activation and dissociation, and hydrogen/deuterium exchange for carbohydrates and glycoconjugates. We also compare the use of different metals for these various techniques and highlight the value in using metals as charge carriers for these analyses. Finally, we provide recommendations for selecting a metal for analysis of carbohydrate adducts and describe areas for continued research. [ABSTRACT FROM AUTHOR]

Carbon Quantum Dots from Natural Sources (NACQDs) is a novel type of carbon-based material that have garnered significant attention due to their remarkable features, including luminescence, photostability, nanoscale size, water solubility, low toxicity, biocompatibility, and cost-effectiveness. The synthesis of NACQDs involves a diverse range of natural sources, such as fruits, foods, beverages, human and animal derivatives, vegetables, leaves, and waste materials. Various synthesis methods, including electrochemical approach, chemical oxidation, hydrothermal carbonization, ultrasonic techniques, microwave-assisted synthesis, solvothermal method, laser ablation technique, thermolysis, and atmospheric plasma-based synthesis, have been explored to tailor the size and properties of NACQDs. Characterization techniques like Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TЕM), ultraviolet absorption, fluorescence properties, and nuclear magnetic resonance (NMR) have provided invaluable insights into the physical and chemical characteristics of NACQDs. This review highlights the immense potential of NACQDs in metal ion sensing applications and underscores the need for further investigation to enhance their reproducibility and precise control over their properties. NACQDs hold great promise as versatile nanomaterials for metal ion sensing and are poised to revolutionize diverse fields, ranging from environmental monitoring to biomedical diagnostics and chemical analysis.

Schiff bases are produced through condensation reactions between aldehydes or ketones and molecules containing an amine group. Given their multifaceted uses across diverse domains, they have gained prominence. Numerous studies have been conducted in this field due to the uncomplicated methods of manufacturing and the abundant range of applications. Investigations into DNA binding are essential for understanding the many interactions between drugs and DNA. DNA binding can be investigated via UV-binding, fluorescence quenching, and viscosity investigations. This study aims to offer several research papers on the DNA binding activity of Schiff base metal complexes and compare them. [ABSTRACT FROM AUTHOR]

Burn dressings have the functions of preventing wound infection, inhibiting inflammation, and promoting wound healing in the treatment of burns, especially in the treatment of refractory burns. Therefore, it is urgent to develop highly efficient burn dressings to treat burns. Burn and wound management is the core of treatment. This article studies the specific roles of different types of dressings in burn wound healing, and elaborates on the application of inorganic dressings containing a single metal element or nanotech-based dressings, as well as heterojunction structures, which provide new options for burn treatment. On this basis, the development direction of burn wound dressings is prospected. [ABSTRACT FROM AUTHOR]

In transdermal drug delivery system (TDDS) patches, achieving prolonged adhesion, high drug loading, and rapid drug release simultaneously presented a significant challenge. In this study, a PHT-SP-Cu2+ adhesive was synthesized using polyethylene glycol (PEG), hexamethylene diisocyanate (HDI), trimethylolpropane (TMP), and silk protein (SP) as functional monomers which were combined with Cu2+ to improve the adhesion, drug loading, and drug release of the patch. The structure of the adhesion chains and the formation of Cu2+-p-π conjugated network in PHT-SP-Cu2+ were characterized and elucidated using different characterization methods including FT-IR, 13C NMR, XPS, SEM imaging and thermodynamic evaluation. The formulation of pressure-sensitive adhesive (PSA) was optimized through comprehensive research on adhesion, mechanics, rheology, and surface energy. The formulation of 3 wt.% SP and 3 wt.% Cu2+ provided superior adhesion properties compared to commercial standards. Subsequently, the peel strength of PHT-SP-Cu2+ was 7.6 times higher than that of the commercially available adhesive DURO-TAK® 87–4098 in the porcine skin peel test. The adhesion test on human skin confirmed that PHT-SP-Cu2+ could adhere to the human body for more than six days. Moreover, the drug loading, in vitro release test and skin permeation test were investigated using ketoprofen as a model drug, and the results showed that PHT-SP-Cu2+ had the efficacy of improving drug compatibility, promoting drug release and enhancing skin permeation as a TDDS. Among them, the drug loading of PHT-SP-Cu2+ was increased by 6.25-fold compared with PHT, and in the in vivo pharmacokinetic analysis, the AUC was similarly increased by 19.22-fold. The mechanism of α-helix facilitated drug release was demonstrated by Flori-Hawkins interaction parameters, molecular dynamics simulations and FT-IR. Biosafety evaluations highlighted the superior skin cytocompatibility and safety of PHT-SP-Cu2+ for transdermal applications. These results would contribute to the development of TDDS patch adhesives with outstanding adhesion, drug loading and release efficiency. A new adhesive, PHT-SP-Cu2+, was created for transdermal drug delivery patches. Polyethylene glycol, hexamethylene diisocyanate, trimethylolpropane, silk protein, and Cu2+ were used in synthesis. Characterization techniques confirmed the structure and Cu2+-p-π conjugated networks. Optimal formulation included 3 wt.% SP and 3 wt.% Cu2+, exhibiting superior adhesion. PHT-SP-Cu2+ showed 7.6 times higher peel strength than DURO-TAK® 87–4098 on porcine skin and adhered to human skin for over six days. It demonstrated a 6.25-fold increase in drug loading compared to PHT, with 19.22-fold higher AUC in vivo studies. α-helix facilitated drug release, proven by various analyses. PHT-SP-Cu2+ showed excellent cytocompatibility and safety for transdermal applications. This study contributes to developing efficient TDDS patches. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Energy Chemical Industry is the property of Energy Chemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present work, we have developed a rapid, cost-effective aqueous phase route to synthesize water-soluble Thioglycolic acid (TGA) capped CdSe/ZnS (CdSe/ZnS + TGA) QD sensor. Synthesized QD sensor has been successfully validated its candidature for the efficient detection of hazardous heavy metal ions (Xn+) specifically chromium (Cr3+) and copper (Cu2+) in aqueous medium. In the presence of Xn+ metal ions, "Turn-Off" fluorescence response is observed due to the complex formation (Xn+: CdSe/ZnS + TGA). A strong 1:1 complexation (Xn+: CdSe/ZnS + TGA) between QD sensor and Xn+ metal ion is confirmed by the output of Benesi–Hildebrand relation and Job's plot. As per our knowledge our proposed CdSe/ZnS + TGA QD sensor has established its efficient sensing capability for metal ions with lower detection of limit (LOD) up to concentration ~ 10–7 M for the first time which is lower than permissible limit as per WHO data. The practical application of this system for determining metal ions in real samples has also been successfully demonstrated. [ABSTRACT FROM AUTHOR]

The transformation of solid wastes from industrial production into effective adsorbents could significantly contribute to wastewater treatment. In this study, after acidizing and burning soft scale (SS) from coal gasification system, two magnetic adsorbents (mag-ASS and mag-BASS) were prepared via the combination of magnetite with ultrasonic, respectively. The treatment effects of mag-ASS and mag-BASS were then investigated for simulated wastewater containing macromolecular organic matter [i.e., methylene blue (MB)] and Ca2+. The results indicated that the pseudo second order kinetic, Elovich, Freundlich, Langmuir and Temkin model could well describe the adsorption behavior of MB and Ca2+ onto mag-ASS and mag-BASS. The maximum adsorption capacities of mag-ASS for MB and mag-BASS for Ca2+ were 600.53 mg/g and 102.54 mg/g, respectively. Surprisingly, the adsorption abilities of mag-ASS for MB and mag-BASS for Ca2+ show significantly higher than the others. The adsorption mechanisms of MB mainly included electrostatic interaction, π-π conjugate interaction and cation exchange, while those of Ca2+ were mainly electrostatic interaction and cation exchange. The diffusion of MB and Ca2+ onto the magnetic adsorbents might be controlled by the combined effects of intraparticle and liquid film diffusion. There was no significant reduction in adsorption capacity after 8 cycles of adsorption and desorption, indicating that SS-based magnetic adsorbents had good recyclability and stability. Moreover, the removal efficiency of mag-BASS for total hardness and total organic carbon in real coal gasification gray water (CGGW) was 82.60 and 64.10%, respectively. The treatment of CGGW and the resource of wastes would significantly promote the reasonable disposal of coal gasification scales. [ABSTRACT FROM AUTHOR]

The interactions of metal ions with fulvic acids were investigated from the point of view of the thermodynamic aspects of complexation as well as the size and charge of the formed complexes. Thermodynamic aspects were studied by means of isothermal titration calorimetry. Particle size distribution was determined by the method of dynamic light scattering and charge by the measurement of zeta potential. Complexation resulted in changes in particle size and charge. The particle size distribution was trimodal for fulvic acids and bimodal for fulvic complexes with calcium and magnesium, while copper–fulvic complexes had only one size fraction. The compensation of the negative charge of carboxylic and phenolic functional groups by positively charged metal ions resulted in an increase in zeta potential which became closer to zero in the case of copper–fulvic complexes. However, all metal–humic complexes behaved as colloidally unstable, which resulted in visually observable sedimentation. Calorimetric measurements provided positive values for changes in enthalpy, which indicated endothermic processes. In contrast, quantum chemical calculations as well as experiments with model compounds provided negative values indicating exothermic processes. Changes in Gibbs energy were determined as negative and changes in entropy as positive. [ABSTRACT FROM AUTHOR]

The molecular orientation of liquid crystalline (LC) hydrogels has the potential to induce a range of functionalities that can deliver great mechanical strength. Sacran is a supergiant LC polysaccharide isolated from the cyanobacterium Aphanothece sacrum with a high amount of anionic functional groups such as sulfates and carboxylates. In this article, ultra-strong sacran hydrogels and their dried fibers were produced by cross-linking under injection flow with trivalent metal ions such as Al3+, Cr3+, Fe3+, In3+, and rare-earth metal ions such Er3+ and Sr3+. Crossed-polarizing microscopy and X-ray diffraction imaging revealed a uniaxial molecular orientation in the LC gel fiber, resulting in outstanding mechanical characteristics. [ABSTRACT FROM AUTHOR]

BACKGROUND: Resistance to the inflammatory response is an important part of promoting the repair of damaged tissue and improving the local inflammatory response caused by medical bio-implant materials has been a key issue to be addressed in recent years. OBJECTIVE: To summarize the anti-inflammatory effects of common metal ions and related molecular mechanisms to provide some theoretical references for improving the early inflammatory response of hosts caused by bio-implant materials. METHODS: A computer search of the relevant literature in PubMed, Web of Science, CNKI and WanFang databases was conducted using “metal ions, magnesium ion, zinc ion, silver ion, copper ion, inflammation, anti-inflammatory effects, oxidative stress, immunoregulation, signaling pathways” as Chinese and English search terms. Preliminary screening was conducted by reading the titles and abstracts. Finally, 80 papers were included for result analysis and summary. RESULTS AND CONCLUSION: (1) Metal ions such as magnesium, zinc, silver and copper have a good anti-inflammatory effect. The strength of this antiinflammatory effect is strongly correlated with the dose and duration of action. In the future, consideration can be given to controlling the release rate of ions and adjusting the appropriate therapeutic concentration to achieve the best anti-inflammatory effect. (2) Magnesium ions and zinc ions exhibit excellent antiinflammatory activity, with magnesium ions often being beneficial in anti-inflammatory therapy in the form of compounds such as magnesium sulfate and zinc ions regulating the body’s inflammatory response with zinc feed as the main source of zinc supplementation. (3) Silver and copper ions have some antiinflammatory effects, but are still predominant for their excellent antibacterial activity, mainly in the form of nanoparticles and bio-coatings. (4) Magnesium and zinc metal ions can be combined with natural extracts to form complexes to exert anti-inflammatory effects, and this method has the advantage of being inexpensive and widely available and is a sustainable and green approach, which is worthy of clinical promotion. (5) Metal ions such as magnesium, zinc, silver and copper exert anti-inflammatory effects by reducing host oxidative stress damage, modulating immune cells and inhibiting inflammatory signaling pathways such as nuclear factor-κB, Toll-like receptor, STAT3 and NOD. (6) The molecular mechanism related to the anti-inflammation of metal ions is a complex network, which is not the effect of a single pathway, but should be a combination of multiple signaling pathways. There are still many potential mechanisms that have not yet been explored, and more systematic elucidation of the interconnections between various signaling pathways is needed in the future. [ABSTRACT FROM AUTHOR]

The detection of metal ions is an option for maintaining water quality and diagnosing metal ion-related diseases. In this study, we successfully detected metal ions using fluorescent peptides in water. First, we prepared seven linear (L1–L7) and seven cyclic (C1–C7) peptides containing two pyrenyl (Pyr) units and assessed the response to various metal ions by fluorescence. The results indicated that C1, which contains a hexameric cyclic peptide moiety consisting of Pyr and Gly units, did not show a fluorescent response to metal ions, while the linear L1 corresponding to C1 showed a response to Cu2+, but its selectivity was found to be poor through a competition assay for each metal ion. We then assessed C2–C7 and L2–L7, in which Gly was replaced by His units at various positions in the same manner. The results showed that C2–C7 responded to Cu2+ in a manner dependent on the His position. Additionally, superior selectivity was observed in C7 through a competition assay. These results demonstrate that the structural restriction of peptides and the sequence affect the selective detection of Cu2+ and reveal that peptides with an appropriate structure can accomplish the fluorescent detection of Cu2+ specifically. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Oilfield Development in Daqing is the property of Editorial Department of Petroleum Geology & Oilfield Development in Daqing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study reports on the highly simple fabrication of green carbon black (GCB) generated from scrap tires with acetic acid to improve the adsorption efficiency for water purification, which is thoroughly compared with conventional carbon black (CB) obtained from petrochemicals. Unlike traditional modification processes with strong acids or bases, the introduction of a relatively mild acid readily allowed for the effective modification of GCB to increase the uptake capability of metal ions and toxic organic dyes to serve as effective adsorbents. The morphological features and thermal decomposition patterns were examined by electron microscopy and thermogravimetric analysis (TGA). The surface functional groups were characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The structural information (ratio of D-defects/G band-graphitic domains) obtained by Raman spectroscopy clearly suggested the successful fabrication of GCB (ID/IG ratio of 0.74), which was distinctively different from typical CB (ID/IG ratio of 0.91). In the modified GCB, the specific surface area (SBET) gradually increased with the reduction of pore size as a function of acetic acid content (52.97 m2/g for CB, 86.64 m2/g for GCB, 102.10-119.50 m2/g for acid-treated GCB). The uptake capability of the modified GCB (312.5 mg/g) for metal ions and organic dyes was greater than that of the unmodified GCB (161.3 mg/g) and typical CB (181.8 mg/g), presumably due to the presence of adsorbed acid. Upon testing them as adsorbents in an aqueous solution, all these carbon materials followed the Langmuir isotherm over the Freundlich model. In addition, the removal rates of cationic species (>70% removal of Cu2+ and crystal violet in 30 min) were much faster and far greater than those of anionic metanil yellow (<40% removal in 3 h), given the strong electrostatic interactions. Thus, this work demonstrates the possibility of recycling waste tires in the powder form of GCB as a cost-effective and green adsorbent that can potentially substitute traditional CB, and the modification strategy provides a proof of concept for developing simple fabrication guidelines of other carbonaceous materials. [ABSTRACT FROM AUTHOR]

The extensive utilization of bismuth and its derivatives in many industries, such as chemical, semiconductor, pharmaceutical, and cosmetics, leads to their accumulation in wastewater, posing a risk to both human health and the environment. Carbon nanorods (CNR) are fluorescent nanoparticles with an ability to detect various analytes as sensing probes. This study focuses on the production, structure, and chemical composition characterization of silkworm-derived CNR (swCNR) and their ability to detect bismuth ions (Bi3+) and inhibit radicals. The optimum wavelength for exciting the fluorescence of swCNR was 370 nm, and the resulting emission peak was observed at 436 nm. The prepared swCNR showed static fluorescence quenching mechanism-based sensing of Bi3+ ions with a limit of detection of 175 nM and two linear ranges from 0.5 to 5 μM (R2 = 0.9997) and 10–50 μM (R2 = 0.9995). The swCNR demonstrated high selectivity in detecting Bi3+ ions in the spiked river water samples, thus establishing the swCNR's role as a nano fluorescence probe designed for the selective detection of Bi3+ ions among other metal ions. Favorable results for the antiradical ability of swCNR were obtained against hydroxyl, 2,2 diphenyl-1 picrylhydrazyl, and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radicals with scavenging percentages of 15, 32, and 90, respectively. The possible applications of swCNR in the environmental and antioxidant sectors are proposed in this study.

Abstract In this research, the adsorption of nickel (Ni), copper (Cu), cadmium (Cd), and zinc (Zn) from real sulfuric leaching solution with weakly acidic resins has been studied using response surface methodology (RSM). The adsorption process on two weakly acidic resins has been investigated as a function of pH, time, temperature, and resin dosage. The experimental results indicate that the amino phosphoric acid resin removed Ni, Cu, Cd, and Zn from an acidic solution very efficiently. Based on the central composite design (CCD) on the RSM, the statistical criteria of correlation coefficient (R2) values of Ni, Cu, Cd, and Zn are 0.9418, 0.9753, 0.9657, and 0.9189, respectively. The adsorption process followed the pseudo-second-order kinetic model and the thermodynamic calculations indicated the chemical interaction between the resin surface and the metal ions. Enthalpy values greater than zero indicate that the adsorption reaction of the metals is endothermic. The optimal adsorption process was carried out at time of 20 min, temperature of 30 0C, pH of 5, and resin dosage of 4 g/L. In these conditions, the adsorption capacity of nickel, copper, cadmium, and zinc were obtained 13.408, 7.087, 4.357, and 15.040 mg/g, respectively.

Pidan is an original traditional food in China, which has attracted extensive attention of researchers because of its unique color, fragrance, taste and functions of clearing heat, purging fire, reducing inflammation. Metallic compounds, alkali concentration, and temperature are important in the process of gel formation. Although many studies related to Pidan have been published, there is no systematic summary on the formation mechanism of gel and flavor profile. In this paper, the regulation mechanism of metal compounds in alkaline solutions, and the formation mechanism of gel, color, flavor profile, and Songhua are systematically and comprehensively reviewed to provide theoretical support for the production development and processing of Pidan.

Radiation damage is an inherent problem in macromolecular crystallography because it impairs the diffraction quality of crystals and produces inaccurate structural information. Understanding radiation damage in protein structures is crucial for accurate structural interpretation and effective data collection. This study undertook X-ray data collection and structure determination of thermolysin (TLN), which contains Zn and Ca ions, by using three different X-ray doses to improve our understanding of the radiation damage phenomena on metal ions in proteins. Data processing revealed typical global radiation damage in TLN, such as an increase in unit cell volume, Rmerge value, and Wilson B-factor. An analysis of the B-factor indicated that radiation damage at the Zn and Ca sites in TLN increased with higher X-ray doses. However, the distance between the metal ions and their interacting residues in TLN was not significantly affected, suggesting that radiation damage to the metal ions has a minimal effect on these interactions. Moreover, the increase in the B-factor of the metal ions according to the X-ray dose was similar to that in the B-factor of the residues interacting with the metal ions. These results expand our understanding of radiation damage phenomena in macromolecules and can be used to improve data collection strategies.

Indeed, considerable efforts have been made in the domain of silver nanoparticles, including the construction and wide‐ranging applications. This work involves the synthesis and characterization of salophen anchored silver nanoparticles (AgNPs), and its utilization for selective detection of Fe2+ and Cu2+ ions in DMSO. These AgNPs were synthesized by the reduction of Ag+ ions with salophen ligand, and were characterized by different techniques which include UV‐visible, fluorescence, FTIR, SEM, EDX, TEM, PXRD, DLS, and zeta potential. The negative zeta potential value of −19.6 mV evidenced the stability of the AgNPs. These AgNPs were found to sense Fe2+ and Cu2+ ions selectively in DMSO solution at various concentrations. Instant color change from olive to brown as well as olive to light olive was observed while detecting Fe2+ and Cu2+ ions by the nanoprobe, respectively. UV‐visible and fluorescence spectroscopic investigations were carried out to establish the sensing ability of the nanoprobe. Additionally, AgNPs revealed promising antibacterial activity selectively against gram‐negative bacteria over gram‐positive bacteria. Thus, our approach opens up a new track to design novel and operative functionalized nanomaterials for real‐life sensing and biomedical applications. [ABSTRACT FROM AUTHOR]

The chalcone compound DHPO was synthesized through a chemical reaction between 1-(2-hydroxyphenyl)-ethanone and 3,4-dimethoxy benzaldehyde under ultrasound irradiation. The interaction between the DHPO compound and several metal ions was studied using fluorescence behavior, revealing that the chalcone function as a "turn on and turn off" switch fluorescent sensor, for selectively and sensitively detecting Fe3+ ions. The process of fluorescence quenching and complexation of DHPO with Fe3+ ion was further studied using methods such as Benesi-Hildebrand, Stern-Volmer plot, and job plot. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (2097-2806) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pidan is an original traditional food in China, which has attracted extensive attention of researchers because of its unique color, fragrance, taste and functions of clearing heat, purging fire, reducing inflammation. Metallic compounds, alkali concentration, and temperature are important in the process of gel formation. Although many studies related to Pidan have been published, there is no systematic summary on the formation mechanism of gel and flavor profile. In this paper, the regulation mechanism of metal compounds in alkaline solutions, and the formation mechanism of gel, color, flavor profile, and Songhua are systematically and comprehensively reviewed to provide theoretical support for the production development and processing of Pidan. [ABSTRACT FROM AUTHOR]

Metal ions exert pivotal functions within the human body, encompassing essential roles in upholding cell structure, gene expression regulation, and catalytic enzyme activity. Additionally, they significantly influence various pathways implicated in divergent mechanisms of cell death. Among the prevailing malignant tumors of the digestive tract worldwide, gastric cancer stands prominent, exhibiting persistent high mortality rates. A compelling body of evidence reveals conspicuous ion irregularities in tumor tissues, encompassing gastric cancer. Notably, metal ions have been observed to elicit distinct contributions to the progression, drug resistance, and biological attributes of gastric cancer. This review consolidates pertinent literature on the involvement of metal ions in the etiology and advancement of gastric cancer. Particular attention is directed towards metal ions, namely, Na, K, Mg, Ca, Fe, Cu, Zn, and Mn, elucidating their roles in the initiation and progression of gastric cancer, cellular demise processes, drug resistance phenomena, and therapeutic approaches. [ABSTRACT FROM AUTHOR]

Copyright of Journal of East China University of Science & Technology is the property of Journal of East China University of Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Metal ions play an important role in the human body. With the progress of material synthesis and processing technology, a variety of metal ions that can be used in bone tissue engineering have been developed, such as magnesium (Mg2+), zinc (Zn2+), manganese (Mn2+), strontium (Sr2+), and copper (Cu2+). OBJECTIVE: To summarize the research progress and development direction of metal ions in bone tissue engineering. METHODS: The literature collected by CNKI, PubMed and WanFang databases from 2014 to 2022 was retrieved. The Chinese and English key words were “metal ions, bone tissue engineering, osteogenic activity, magnesium ions, zinc ions, manganese ions, strontium ions, copper ions, calcium ions, lithium ions, cobalt ions”. RESULTS AND CONCLUSION: Different metal ions will be released to varying degrees after the materials are implanted into the body, which can change the tissue microenvironment, thus improving the ability of materials to form blood vessels and bones. Compared with growth factors, metal ions are easier to control the release rate, have lower cost, and can also improve the mechanical properties of implant materials. The application of metal ions in bone tissue engineering is full of prospects. Although some metal ions can already be used to treat bone defects, the mechanism of action of many metal ions in the human body is not completely clear, and the application effect is a lack of clinical experiment verification. Further exploration is needed before clinical application. [ABSTRACT FROM AUTHOR]

Surface defects of metal halide perovskite nanocrystals (PNCs) substantially compromise the optoelectronic performances of the materials and devices via undesired charge recombination. However, those defects, mainly the vacancies, are structurally entangled with each other in the PNC lattice, necessitating a delicately designed strategy for effective passivation. Here, a synergistic metal ion doping and surface ligand exchange strategy is proposed to passivate the surface defects of CsPbBr3 PNCs with various divalent metal (e.g., Cd2+, Zn2+, and Hg2+) acetate salts and didodecyldimethylammonium (DDA+) via one‐step post‐treatment. The addition of metal acetate salts to PNCs is demonstrated to suppress the defect formation energy effectively via the ab initio calculations. The developed PNCs not only have near‐unity photoluminescence quantum yield and excellent stability but also show luminance of 1175 cd m−2, current efficiency of 65.48 cd A−1, external quantum efficiency of 20.79%, wavelength of 514 nm in optimized PNC light‐emitting diodes with Cd2+ passivator and DDA ligand. The "organic–inorganic" hybrid engineering approach is completely general and can be straightforwardly applied to any combination of quaternary ammonium ligands and source of metal, which will be useful in PNC‐based optoelectronic devices such as solar cells, photodetectors, and transistors. [ABSTRACT FROM AUTHOR]

Chelating agents are commonly employed in microelectronic processes to prevent metal ion contamination. The ligand fragments of a chelating agent largely determine its binding strength to metal ions. Identification of ligands with suitable characteristics will facilitate the design of chelating agents to enhance the capture and removal of metal ions from the substrate in microelectronic processes. This study employed quantum chemical calculations to simulate the binding process between eleven ligands and the hydrated forms of Ni2+, Cu2+, Al3+, and Fe3+ ions. The binding strength between the metal ions and ligands was quantified using binding energy and binding enthalpy. Additionally, we explored the binding interaction mechanisms and explained the differences in binding abilities of the eleven ligands using frontier molecular orbitals, nucleophilic indexes, electrostatic potentials, and energy decomposition calculations based on molecular force fields. Based on our computational results, promising chelating agent structures are proposed, aiming to guide the design of new chelating agents to address metal ion contamination issues in integrated circuit processes. [ABSTRACT FROM AUTHOR]

Terminal 2′-deoxynucleotidyl transferase (TdT) is a unique enzyme capable of catalysing template-independent elongation of DNA 3′ ends during V(D)J recombination. The mechanism controlling the enzyme's substrate specificity, which is necessary for its biological function, remains unknown. Accordingly, in this work, kinetic and mutational analyses of human TdT were performed and allowed to determine quantitative characteristics of individual stages of the enzyme–substrate interaction, which overall may ensure the enzyme's operation either in the distributive or processive mode of primer extension. It was found that conformational dynamics of TdT play an important role in the formation of the catalytic complex. Meanwhile, the nature of the nitrogenous base significantly affected both the dNTP-binding and catalytic-reaction efficiency. The results indicated that neutralisation of the charge and an increase in the internal volume of the active site caused a substantial increase in the activity of the enzyme and induced a transition to the processive mode in the presence of Mg2+ ions. Surrogate metal ions Co2+ or Mn2+ also may regulate the switching of the enzymatic process to the processive mode. Thus, the totality of individual factors affecting the activity of TdT ensures effective execution of its biological function. [ABSTRACT FROM AUTHOR]