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Purines are the building blocks of DNA/RNA, energy substrates, and cofactors. Purine metabolites, including ATP, GTP, NADH, and coenzyme A, are essential molecules in diverse biological processes such as energy metabolism, signal transduction, and enzyme activity. When purine levels increase, excess purines are either recycled to synthesize purine metabolites or catabolized to the end product uric acid. Purine catabolism increases during states of low oxygen tension (hypoxia and ischemia), but this metabolic pathway is incompletely understood in the context of histotoxic hypoxia (i.e., inhibition of oxygen utilization despite normal oxygen tension). In rabbits exposed to cyanide-a classical histotoxic hypoxia agent-we demonstrated significant increases in several concordant metabolites in the purine catabolic pathway (including plasma levels of uric acid, xanthosine, xanthine, hypoxanthine, and inosine) via mass spectrometry-based metabolite profiling. Pharmacological inhibition of the purine catabolic pathway with oxypurinol mitigated the deleterious effects of cyanide on skeletal muscle cytochrome c oxidase redox state, measured by non-invasive diffuse optical spectroscopy. Finally, plasma uric acid levels correlated strongly with those of lactic acid, an established clinical biomarker of cyanide exposure, in addition to a tissue biomarker of cyanide exposure (skeletal muscle cytochrome c oxidase redox state). Cumulatively, these findings not only shed light on the in vivo role(s) of cyanide but also have implications in the field of medical countermeasure (MCM) development.

Globally, environmental pollution continues to be a significant public health problem, and according to the World Health Organisation, pollution-induced deaths account for 23% of deaths yearly, which could be prevented if people lived in healthier environments. Despite implementing multilateral agreements and international treaties such as the Bamako, Basel, Rotterdam, Minamata, and Stockholm conventions, the United Nations Sustainable Development Goals, and national laws, toxic pollutants remain a serious environmental and public health problem in low-income countries. In the specific context of Kwekwe City, an industrial and mining area in Zimbabwe, where environmental and pollution-induced health problems associated with industries have been widely reported, this study was conducted in close collaboration with the local community. The study aimed to assess community members' perceptions regarding health risks associated with potentially toxic elements and cyanide pollution in Kwekwe City. An explorative cross-sectional study was conducted with key stakeholders and industrial settlements' residents. Face-to-face interviews with key informants and focus group discussions with residents and workers were used to gather data. A thematic approach was utilised in data analysis. Study participants, who played a crucial role in the research process, perceived that industrial pollution principally linked to cyanide, mercury and chromium posed significant environmental and health risks. This participatory approach in risk perception assessment is critical in providing insight into the scope of the problem and formulating intervention strategies. However, given that qualitative study results lack generalisability and replicability, quantitative studies need to be undertaken to determine environmental levels of toxic chemical pollutants as a complementary and validative measure. [ABSTRACT FROM AUTHOR]

Ecuador is a developing country that relies on mining as a significant source of economic income every year; however, there needs to be more studies on the soil pollution caused by mining over time. Biological remediation as an alternative to the use of physical and chemical methods offers a more cost-effective and environmentally friendly means to counteract the negative impacts that the presence of heavy metals in mining tailings soils can cause. This study focused on soil sampling from the mining tailings of the San Carlos de las Minas sector, in the Zamora Chinchipe province in Ecuador, to find potential bacterial strains that can degrade two specific contaminants, mercury (Hg) and cyanide (CN-). For this purpose, 68 soil subsamples were collected. pH, electrical conductivity, moisture, and the concentration of the contaminants were analyzed and measured. The initial concentration of CN- was 0.14 mg/kg, and of Hg was 88.76 mg/kg. From the soil samples, eight bacterial strains were isolated, characterized at macroscopic and microscopic levels, and identified at the molecular level. The bacteria were then subjected to degradability tests for CN- and Hg, obtaining interesting results. The degradation capacity of CN- stood out for the strains Micrococcus aloeverae and Pseudomonas alcaliphila, and for the degradation of Hg, the strains Hydrogenophaga laconesensis and Micrococcus aloeverae were highlighted, achieving degradation percentages of up to 98.80%. These results emphasize the discovery of these bacterial species with potential use in cyanide and mercury remediation processes.

Simple and efficient sample pretreatment methods are important for analysis and detection of chemical warfare agents (CWAs) in environmental and biological samples. Despite many commercial materials or reagents that have been already applied in sample preparation, such as SPE columns, few materials with specificity have been utilized for purification or enrichment. In this study, ionic magnetic mesoporous nanomaterials such as poly(4-VB)@M-MSNs (magnetic mesoporous silicon nanoparticles modified by 4-vinyl benzene sulfonic acid) and Co2+@M-MSNs (magnetic mesoporous silicon nanoparticles modified by cobalt ions) with high absorptivity for ethanol amines (EAs, nitrogen mustard degradation products) and cyanide were successfully synthesized. The special nanomaterials were obtained by modification of magnetic mesoporous particles prepared based on co-precipitation using -SO3H and Co2+. The materials were fully characterized in terms of their composition and structure. The results indicated that poly(4-VB)@M-MSNs or Co2+@M-MSNs had an unambiguous core-shell structure with a BET of 341.7 m2·g−1 and a saturation magnetization intensity of 60.66 emu·g−1 which indicated the good thermal stability. Poly(4-VB)@M-MSNs showed selective adsorption for EAs while the Co2+@M-MSNs were for cyanide, respectively. The adsorption capacity quickly reached the adsorption equilibrium within the 90 s. The saturated adsorption amounts were MDEA = 35.83 mg·g−1, EDEA = 35.00 mg·g−1, TEA = 17.90 mg·g−1 and CN−= 31.48 mg·g−1, respectively. Meanwhile, the adsorption capacities could be maintained at 50–70% after three adsorption–desorption cycles. The adsorption isotherms were confirmed as the Langmuir equation and the Freundlich equation, respectively, and the adsorption mechanism was determined by DFT calculation. The adsorbents were applied for enrichment of targets in actual samples, which showed great potential for the verification of chemical weapons and the destruction of toxic chemicals. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are frequently utilized as sensing materials. Unfortunately, the low conductivity of MOFs hinder their further application in electrochemical determination. To overcome this limitation, a novel modification strategy for MOFs was proposed, establishing an electrochemical determination method for cyanides in Baijiu. Co and Ni were synergistically used as the metal active centers, with meso−Tetra(4−carboxyphenyl)porphine (TCPP) and Ferrocenecarboxylic acid (Fc−COOH) serving as the main ligands, synthesizing Ni/Co−MOF−TCPP−Fc through a hydrothermal method. The prepared MOF exhibited improved conductivity and stable ratio signals, enabling rapid and sensitive determination of cyanides. The screen−printed carbon electrodes (SPCE) were suitable for in situ and real−time determination of cyanide by electrochemical sensors due to their portability, low cost, and ease of mass production. A logarithmic linear response in the range of 0.196~44 ng/mL was demonstrated by this method, and the limit of detection (LOD) was 0.052 ng/mL. Compared with other methods, the sensor was constructed by a one−step synthesis method, which greatly simplifies the analysis process, and the determination time required was only 4 min. During natural cyanide determinations, recommended readouts match well with GC−MS with less than 5.9% relative error. Moreover, this electrochemical sensor presented a promising method for assessing the safety of cyanides in Baijiu. [ABSTRACT FROM AUTHOR]

The release of cyanide from cyanogenic precursors is the central core of the plant defences based on the cyanogenesis process. Although cyanide is formed as a coproduct of some metabolic routes, its production is mostly due to the degradation of cyanohydrins originating from cyanogenic glycosides in cyanogenic plants and the 4-OH-ICN route in Brassicaceae. Cyanohydrins are then hydrolysed in a reversible reaction generating cyanide, being both, cyanohydrins and cyanide, toxic compounds with potential defensive properties against pests and pathogens. Based on the production of cyanogenic-derived molecules in response to the damage caused by herbivore infestation, in this review, we compile the actual knowledge of plant cyanogenic events in the plant–pest context. Besides the defensive potential, the mode of action, and the targets of the cyanogenic compounds to combat phytophagous insects and acari, special attention has been paid to arthropod responses and the strategies to overcome the impact of cyanogenesis. Physiological and behavioural adaptations, as well as cyanide detoxification by β-cyanoalanine synthases, rhodaneses, and cyanases are common ways of phytophagous arthropods defences against the cyanide produced by plants. Much experimental work is needed to further understand the complexities and specificities of the defence–counter-defence system to be applied in breeding programs. [ABSTRACT FROM AUTHOR]

A novel indolium-based fluorescent probe for the detection of CN− was developed based on the conjugation of 1, 2, 3, 3-Tetramethyl-3H-indolium iodide and 2-acetyl benzothiophene. The introduction of external CN− caused a nucleophilic attack to the quaternary amine salt structure in the probe and resulted in the departure of iodide ions and the steric rotation of the index salt group, which caused fluorescence quenching. The titration experiments showed that the probe had rapid qualitative and quantitative analysis capabilities for CN−. Moreover, the relevant biocompatibility experiments also demonstrated the potential application value of the probe. [ABSTRACT FROM AUTHOR]

Ecuador is a developing country that relies on mining as a significant source of economic income every year; however, there needs to be more studies on the soil pollution caused by mining over time. Biological remediation as an alternative to the use of physical and chemical methods offers a more cost-effective and environmentally friendly means to counteract the negative impacts that the presence of heavy metals in mining tailings soils can cause. This study focused on soil sampling from the mining tailings of the San Carlos de las Minas sector, in the Zamora Chinchipe province in Ecuador, to find potential bacterial strains that can degrade two specific contaminants, mercury (Hg) and cyanide (CN-). For this purpose, 68 soil subsamples were collected. pH, electrical conductivity, moisture, and the concentration of the contaminants were analyzed and measured. The initial concentration of CN- was 0.14 mg/kg, and of Hg was 88.76 mg/kg. From the soil samples, eight bacterial strains were isolated, characterized at macroscopic and microscopic levels, and identified at the molecular level. The bacteria were then subjected to degradability tests for CN- and Hg, obtaining interesting results. The degradation capacity of CN- stood out for the strains Micrococcus aloeverae and Pseudomonas alcaliphila , and for the degradation of Hg, the strains Hydrogenophaga laconesensis and Micrococcus aloeverae were highlighted, achieving degradation percentages of up to 98.80%. These results emphasize the discovery of these bacterial species with potential use in cyanide and mercury remediation processes. [ABSTRACT FROM AUTHOR]

Molecular studies about cyanide biodegradation have been mainly focused on the hydrolytic pathways catalyzed by the cyanide dihydratase CynD or the nitrilase NitC. In some Pseudomonas strains, the assimilation of cyanide has been linked to NitC, such as the cyanotrophic model strain Pseudomonas pseudoalcaligenes CECT 5344, which has been recently reclassified as Pseudomonas oleovorans CECT 5344. In this work, a phylogenomic approach established a more precise taxonomic position of the strain CECT 5344 within the species P. oleovorans. Furthermore, a pan-genomic analysis of P. oleovorans and other species with cyanotrophic strains, such as P. fluorescens and P. monteilii, allowed for the comparison and identification of the cioAB and mqoAB genes involved in cyanide resistance, and the nitC and cynS genes required for the assimilation of cyanide or cyanate, respectively. While cyanide resistance genes presented a high frequency among the analyzed genomes, genes responsible for cyanide or cyanate assimilation were identified in a considerably lower proportion. According to the results obtained in this work, an in silico approach based on a comparative genomic approach can be considered as an agile strategy for the bioprospection of putative cyanotrophic bacteria and for the identification of new genes putatively involved in cyanide biodegradation. [ABSTRACT FROM AUTHOR]

Background: Cyanide is a very toxic chemical that reacts with the ferric cytochrome oxidase in the mitochondrial system to form a stable complex. This complex inhibits the process of oxidative phosphorylation, thereby interrupting aerobic respiration in the organism. It is postulated that activated charcoal (AC) intercepts the ingested cyanide in the gastrointestinal tract before it is absorbed into the system. Methods: A single dose of 3 mg/kg body weight of potassium cyanide (KCN) was orally administered to the rats in each of the five groups, each consisting of 6 rats. After 15 minutes, all rats in each group were given AC from different agro-based materials. The control group (group 1) received standard commercial AC orally at 1 g/kg. group 2 received AC from plantain peels, group 3 received AC from castor oil seed shell, group 4 received AC from coconut shell and group 5 received a combination of AC from plantain peels, castor oil seed shell, and coconut shell. Blood samples were collected sequentially from rats in each group for biochemical assays using standard procedures. Results: The control group, which received KCN and standard commercial AC, exhibited the highest alanine transaminase (ALT) value (60.09±0.10 U/L) on day seven. Similarly, the highest aspartate transaminase (AST) value (196.28±0.72 U/L) was observed in the control group. Alkaline phosphate (ALP) levels followed a similar pattern. On day seven, the serum creatinine levels were 3.81±0.11 mg/dL for group 1 and 3.45±0.05 mg/dL for group 5. Subsequently, all biochemical parameters decreased after day 7, with the lowest levels recorded in rats that received AC derived from coconut shells. Conclusion: The administration of locally prepared agro-based adsorbents to Wistar rats after exposure to sublethal doses of cyanide significantly mitigated the effects of the cyanide on the liver, kidneys, and heart, as indicated by the biochemical parameters of the albino Wistar rats in the study.

Nanoparticles of TiO2 doped with low amount of Fe were synthesized from natural ilmenite obtained from alluvial gold mine wastes. The obtained TiO2 were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier-transform infrared spectroscopy (FTIR), UV-Vis diffuse reflectance, thermogravimetric analysis/differential scanning calorimetry (TGA/DSC), N2 adsorption-desorption isotherms, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The results confirm the formation of mesoporous TiO2 nanoparticles in anatase phase with 0.05 wt.% of iron possibly replacing some titanium places. All the characterizations were performed to the synthesized solid and the reference materials (TiO2 anatase and Degussa P25). The photocatalytic activity of both the synthesized solid and references were evaluated in the photo-oxidation of cyanide in aqueous medium under UV illumination. An experimental design type Box-Behnken was performed choosing three different parameters: the initial concentration of cyanide (50, 150 and 250 ppm) the catalyst load (0.1, 0.5 and 1.0 g L-1) and the oxygen source. The percentage of cyanide conversion was chosen as response in the design obtaining as optimal conditions [CN-]0 = 50 ppm, catalyst load = 0.6 g L-1 and air bubbling. Under these conditions it was reached 32, 32 and 89% of cyanide conversion for Fe-TiO2 synthesized, TiO2 anatase and Degussa P25, respectively.

In addition to its role as a toxic environmental contaminant, cyanide has been hypothesized to play a key role in prebiotic chemistry and early biogeochemical evolution. While cyanide-hydrolyzing enzymes have been studied and engineered for bioremediation, the extant diversity of these enzymes remains underexplored. Additionally, the age and evolution of microbial cyanide metabolisms is poorly constrained. Here we provide comprehensive phylogenetic and molecular clock analyses of the distribution and evolution of the Class I nitrilases, thiocyanate hydrolases, and nitrile hydratases. Molecular clock analyses indicate that bacterial cyanide-reducing nitrilases were present by the Paleo- to Mesoproterozoic, and were subsequently horizontally transferred into eukaryotes. These results present a broad diversity of microbial enzymes that could be optimized for cyanide bioremediation.

Abstract Background Basal energetic metabolism in sperm, particularly oxidative phosphorylation, is known to condition not only their oocyte fertilising ability, but also the subsequent embryo development. While the molecular pathways underlying these events still need to be elucidated, reactive oxygen species (ROS) could have a relevant role. We, therefore, aimed to describe the mechanisms through which mitochondrial activity can influence the first stages of embryo development. Results We first show that embryo development is tightly influenced by both intracellular ROS and mitochondrial activity. In addition, we depict that the inhibition of mitochondrial activity dramatically decreases intracellular ROS levels. Finally, we also demonstrate that the inhibition of mitochondrial respiration positively influences sperm DNA integrity, most likely because of the depletion of intracellular ROS formation. Conclusion Collectively, the data presented in this work reveals that impairment of early embryo development may result from the accumulation of sperm DNA damage caused by mitochondrial-derived ROS.

The threat to groundwater by toxic wastewater in the vicinity of cassava processing mills has not been taken seriously in the Niger delta region. Consequently, the fate of cyanide from the surficial surface into underlying aquifers was modelled by MODFLOW and MT3DMS. The vulnerability is influenced by subsurface geology, vertical hydraulic conductivity and sorptive characteristics of the unsaturated zones, seasonal recharge and depth to water levels. The migration of cyanide is considerably not different from the direction of groundwater flow. Its migration is significantly affected by the geology and constituents of the unsaturated zones which retard the spread of cyanide plume into the underlying aquifers. The study has successfully demonstrated the effectiveness of MODFLOW and MT3DMS in determining the vulnerability of aquifers to cassava wastewater from processing mills and associated contaminants. The pumped-and- treat technique is specifically suggested for the remediation of cyanide contaminated aquifers characterized by high hydraulic conductivity.

Cyanide poisoning remains a significant concern for both civilian and military personnel worldwide. Rhodanese, a cyanide detoxify enzyme produced by the wild (KOJCM1665) and two selected mutant strains (KOJCM1665c and KOJCM1665d) of Klebsiella oxytoca JCM 1665 was purified and characterized using a combination of standard techniques. Extracellular rhodanese yield of the wild and selected mutants were 6.2 ± 0.6, 26.7 ± 0.7 and 18.3 ± 0.3 U/mL respectively. The overall levels of recovery of rhodanese activity and fold after purification were 49 %, 66 %, and 58 % and 2.6, 2.6, and 2.3 % for the wild, KOJCM 1665c, and KOJCM 1665d, respectively. The native molecular weights of the three enzyme preparations were 35.1, 34.9, and 34.8 kDa, while the subunit molecular weight was 35 kDa for all the enzymes. The optimum activity of the enzymes was observed at 50 °C and pH 6.0. The real km of the three enzyme preparations for KCN as a substrate were 1.03 × 10−3, 0.95 × 10−3, and 0.80 × 10−3 M, respectively, while the km for the second substrate (Na2S2O3) were 0.59 × 10−3, 0.49 × 10−3, and 0.69 × 10−3 M, respectively. The substrate specificity study showed that the enzyme preferred sodium thiosulfate as the substrate. Metal ions such as Na+ and K+ had significantly greater inhibitory effects on enzyme activity. This study demonstrated the potential of enhancing K. oxytoca JCM 1665 to overexpress extracellular rhodanese, and the physicochemical properties of the enzyme hold significant promise as a target for improving the efficiency of cyanide bioremediation processes.

Konzo, a disease characterized by sudden, irreversible spastic paraparesis, affecting up to 10% of the population in some regions of Sub-Saharan Africa during outbreaks, is strongly associated with dietary exposure to cyanogenic bitter cassava. The molecular mechanisms underlying the development of konzo remain largely unknown. Here, through an analysis of 16 individuals with konzo and matched healthy controls from the same outbreak zones, we identified 117 differentially methylated loci involved in numerous biological processes that may identify cyanogenic-sensitive regions of the genome, providing the first study of epigenomic alterations associated with a clinical phenotype of konzo.

Ethyl carbamate (EC) is a 2A classified carcinogen in Chinese liquor that has raised many problems regarding food safety. Applying microorganisms to control the content of EC precursors in fermented grains has been proven as an effective method to reduce EC in alcoholic beverages. However, the utilization of microorganisms to decrease the precursors of EC (urea and cyanide) is still incomplete in regard to Chinese liquor. Thus, it is necessary to isolate strains with the degradative activities of urea and cyanide. Herein, Bacillus sonorensis F3 and Bacillus licheniformis YA2 strains were isolated from the fermented grains through multiple rounds of high-throughput screening, and the degradative abilities in urea and cyanide reached 95.72% and 75.48%, respectively. In addition, the urease from the B. sonorensis F3 strain and the carbon nitrogen hydrolase from the B. licheniformis YA2 strain were identified by the heterogeneous expression in Escherichia coli. Then, both F3 and YA2 strains were combined at a ratio of 5:1 and applied to eliminate the EC in the simulated fermentation of Chinese liquor; as a result, 51.10% of EC was reduced without affecting the main composition of flavor substances. The obtained strains have great potential in terms of the improvement of quality and safety of Chinese liquor. [ABSTRACT FROM AUTHOR]

Microbial treatment of free-cyanide-polluted wastewater is a cost-effective, efficient, and eco-friendly method. Free-cyanide-degrading microbial cultures were isolated from different sources using batch-enrichment culture techniques, with acetate as the carbon source. Five microbial cultures were able to tolerate and grow at 1500 mg/L free cyanide, which was used as the only nitrogen source under strongly alkaline conditions (pH = 11). Among them, one bacterial strain (B11) was selected for further study because of its high free-cyanide-biodegradation efficiency. Bacterial strain B11 was molecularly identified as Bacillus licheniformis CDBB B11. Free cyanide inhibited the growth rate of B. licheniformis CDBB B11 at initial cyanide concentrations >75 mg/L. Despite this, the bacterial strain demonstrated 100% cyanide-biodegradation efficiency at initial cyanide concentrations ranging from 25 to 75 mg/L, which decreased to 32% as the initial cyanide concentration increased from 75 to 1500 mg/L. Free-cyanide biodegradation corresponds to bacterial growth and ammonia accumulation in the culture medium. The alkaliphilic B. licheniformis CDBB B11 strain is a robust candidate for the detoxification of free-cyanide-laden wastewater because it tolerates and efficiently degrades free cyanide at concentrations of up to 1500 mg/L. [ABSTRACT FROM AUTHOR]

In this study, we synthesized a coumarin–hemicyanine-based deep red fluorescent dye that exhibits an intramolecular charge transfer (ICT). The probe had a large Stokes shift of 287 nm and a large molar absorption coefficient (ε = 7.5 × 105 L·mol−1·cm−1) and is best described as a deep red luminescent fluorescent probe with λem = 667 nm. The color of probe W changed significantly when it encountered cyanide ions (CN−). The absorption peak (585 nm) decreased gradually, and the absorption peak (428 nm) increased gradually, so that cyanide (CN−) could be identified by the naked eye. Moreover, an obvious fluorescence change was evident before and after the reaction under irradiation using 365 nm UV light. The maximum emission peak (667 nm) decreased gradually, whilst the emission peak (495 nm) increased gradually, which allowed for the proportional fluorescence detection of cyanide (CN−). Using fluorescence spectrometry, the fluorescent probe W could linearly detect CN− over the concentration range of 1–9 μM (R2 = 9913, RSD = 0.534) with a detection limit of 0.24 μM. Using UV-Vis spectrophotometry, the linear detection range for CN− was found to be 1–27 μM (R2 = 0.99583, RSD = 0.675) with a detection limit of 0.13 μM. The sensing mechanism was confirmed by 1H NMR spectroscopic titrations, 13C NMR spectroscopy, X-ray crystallographic analysis and HRMS. The recognition and detection of CN− by probe W was characterized by a rapid response, high selectivity, and high sensitivity. Therefore, this probe provides a convenient, effective and economical method for synthesizing and detecting cyanide efficiently and sensitively. [ABSTRACT FROM AUTHOR]

Background: Basal energetic metabolism in sperm, particularly oxidative phosphorylation, is known to condition not only their oocyte fertilising ability, but also the subsequent embryo development. While the molecular pathways underlying these events still need to be elucidated, reactive oxygen species (ROS) could have a relevant role. We, therefore, aimed to describe the mechanisms through which mitochondrial activity can influence the first stages of embryo development. Results: We first show that embryo development is tightly influenced by both intracellular ROS and mitochondrial activity. In addition, we depict that the inhibition of mitochondrial activity dramatically decreases intracellular ROS levels. Finally, we also demonstrate that the inhibition of mitochondrial respiration positively influences sperm DNA integrity, most likely because of the depletion of intracellular ROS formation. Conclusion: Collectively, the data presented in this work reveals that impairment of early embryo development may result from the accumulation of sperm DNA damage caused by mitochondrial-derived ROS. [ABSTRACT FROM AUTHOR]

The following paper is the second part of an article dealing with the mining accident that took place in 2000 in the Romanian town of Baia Mare, which has been described as one of the worst environmental disasters since the Chernobyl accident. The first part focused on the circumstances of the accident, its consequences, and an analysis of the international legal framework in force at the time of the incident. The authors also describe the changes in international law adopted in response to the accident in Baia Mare and analyse the relevant case-law of the ECtHR related to the Baia Mare accident, Tătar v. Romania case. In the second part of the article, the authors discuss the response to the accident at the level of the European Union and the key changes in EU legislation adopted as a result of the accident. The article also points to changes made in national law in the Czech Republic, which directly or indirectly responded to the accident in Baia Mare. In conclusion, the authors relate this mine accident to the accident on the Bečva River that occurred in 2020. [ABSTRACT FROM AUTHOR]

A new fluorescent sensor for the detection of CN− was developed based on the conjugation of phenothiazine fluorophore and benzofuran unit. By the nucleophilic attacking of CN− to the fluoroacetylamino group in the sensor, the additional reaction of CN− and carbonyl group induced the ICT (intramolecular charge transfer) effect in the molecule and caused the fluorescence quenching sensor. The titration experiments show that the sensor has good sensitivity, selectivity and quick response for CN−. In addition, the fluorescent detection of CN− in the living cell and zebrafish experiments demonstrated the value of the sensor in tracing the CN− in biological systems. [ABSTRACT FROM AUTHOR]

Microbial treatment of free-cyanide-polluted wastewater is a cost-effective, efficient, and eco-friendly method. Free-cyanide-degrading microbial cultures were isolated from different sources using batch-enrichment culture techniques, with acetate as the carbon source. Five microbial cultures were able to tolerate and grow at 1500 mg/L free cyanide, which was used as the only nitrogen source under strongly alkaline conditions (pH = 11). Among them, one bacterial strain (B11) was selected for further study because of its high free-cyanide-biodegradation efficiency. Bacterial strain B11 was molecularly identified as Bacillus licheniformis CDBB B11. Free cyanide inhibited the growth rate of B. licheniformis CDBB B11 at initial cyanide concentrations >75 mg/L. Despite this, the bacterial strain demonstrated 100% cyanide-biodegradation efficiency at initial cyanide concentrations ranging from 25 to 75 mg/L, which decreased to 32% as the initial cyanide concentration increased from 75 to 1500 mg/L. Free-cyanide biodegradation corresponds to bacterial growth and ammonia accumulation in the culture medium. The alkaliphilic B. licheniformis CDBB B11 strain is a robust candidate for the detoxification of free-cyanide-laden wastewater because it tolerates and efficiently degrades free cyanide at concentrations of up to 1500 mg/L.

Cyanide is a highly toxic substance present in wastewater from various industries. This study investigates the removal of cyanide species (CS) from aqueous solutions using the ZnTiO3/TiO2/H2O2/UVB system. ZnTiO3/TiO2 nanoparticles synthesized by the sol-gel method were characterized by powder X-ray diffractometry (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The adsorption capacity of nanoparticles was tested by varying the pH of the solution, adsorbent concentration, and contact time. The adsorption of CS on ZnTiO3 and TiO2 surfaces was verified by Density Functional Theory (DFT) calculations. Photocatalytic experiments were achieved under UVB irradiation (λ = 310 nm). The response surface methodology (RSM) was used to optimize the CS removal efficiency. The detoxification effect was evaluated by acute toxicity tests with brine shrimp. The theoretical results show that the adsorption of CS is energetically more favorable on the ZnTiO3 surface than on the TiO2 surface. The experimental results show that the system consisting of ZnTiO3/TiO2 (200 mg L−1), H2O2 (0.1%), and UVB light removes 99% of CS from aqueous solutions after 60 min and reduces the mortality of nauplii in 90% after 90 min. This system was reused in five consecutive cycles with a total loss of efficiency of 30%. [ABSTRACT FROM AUTHOR]

Cyanide (in the form of cyanide anion (CN−) or hydrogen cyanide (HCN), inclusively represented as CN) can be a rapidly acting and deadly poison, but it is also a common chemical component of a variety of natural and anthropogenic substances. The main mechanism of acute CN toxicity is based on blocking terminal electron transfer by inhibiting cytochrome c oxidase, resulting in cellular hypoxia, cytotoxic anoxia, and potential death. Due to the well-established link between blood CN concentrations and the manifestation of symptoms, the determination of blood concentration of CN, along with the major metabolite, thiocyanate (SCN–), is critical. Because currently there is no method of analysis available for the simultaneous detection of CN and SCN– from blood, a sensitive method for the simultaneous analysis of CN and SCN– from human ante- and postmortem blood via liquid chromatography–tandem MS analysis was developed. For this method, sample preparation for CN involved active microdiffusion with subsequent chemical modification using naphthalene-2,3-dicarboxaldehyde (NDA) and taurine (i.e., the capture solution). Preparation for SCN– was accomplished via protein precipitation and monobromobimane (MBB) modification. The method produced good sensitivity for CN with antemortem limit of detection (LODs) of 219 nM and 605 nM for CN and SCN–, respectively, and postmortem LODs of 352 nM and 509 nM. The dynamic ranges of the method were 5–500 µM and 10–500 µM in ante- and postmortem blood, respectively. In addition, the method produced good accuracy (100 ± 15%) and precision (≤ 15.2% relative standard deviation). The method was able to detect elevated levels of CN and SCN– in both antemortem (N = 5) and postmortem (N = 4) blood samples from CN-exposed swine compared to nonexposed swine. [ABSTRACT FROM AUTHOR]

Cyanide (CN) is a toxic environmental pollutant generated by various industrial activities, necessitating the application of bioremediation techniques for its degradation. Biodegradation is a more cost-effective and environmentally friendly technique with high efficiency in CN removal. This study isolated cyanide-degrading bacteria from Tutupaca mining site soil from Tacna, Peru. Bacillus subtilis strain TT10s was selected for its exceptional capacity to rapidly and completely eliminate cyanide under alkaline conditions (pH 10.5), removing 1000 ppm cyanide within 48 h. A kinetic analysis revealed that the biodegradation follows second-order rate kinetics (k2 = 0.08649 mg/(mg·h), R2 = 0.96622), consistent with the literature attribution of the rate-limiting step to the inducible cyanide dihydratase enzyme, which converts cyanide into ammonia and formate via the Michaelis–Menten model. Fourier-transform infrared spectroscopy (FTIR) spectral analysis further corroborated this enzymatic mechanism, showing the disappearance of CN peaks coupled with the emergence of ammonia (NH) and formate (C=O) peaks. Quantitative kinetic modelling integrated with FTIR profiles and degradation curves implicates cyanide dihydratase as the key rate-controlling enzyme in alkaline cyanide biodegradation without the need for an extra carbon source, generating interest for future bioremediation applications in highly contaminated environments. [ABSTRACT FROM AUTHOR]

The following paper traces the circumstances of the 2000 mining accident in the Romanian town of Baia Mare, which has been described as one of the worst environmental disasters since Chornobyl. Following this, the authors analyze the international legislation in force at the time of this accident and mention two types of obligations resulting from international treaties in force at the time, to which Romania was also a contracting party. At the turn of the millennium, there was a lack of legislation at the international and European Commission level to regulate this waste management process, making the whole process riskier and, in some cases, was also the reason for mining accidents associated with cyanide leaks into the environment. The authors describe the changes in international law adopted in response to the mining accidents, cite the case-law of the ECtHR related to the Baia Mare accident case (case Tatar v Romania). The authors leave aside the European and Czech aspects of the issue, which they will focus on in a separate article. [ABSTRACT FROM AUTHOR]

Inducing carotid body anoxia through the administration of cyanide can result in oxygen deprivation. The lack of oxygen activates cellular responses in specific regions of the central nervous system, including the Nucleus Tractus Solitarius, hypothalamus, hippocampus, and amygdala, which are regulated by afferent pathways from chemosensitive receptors. These receptors are modulated by the brain-derived neurotrophic factor receptor TrkB. Oxygen deprivation can cause neuroinflammation in the brain regions that are activated by the afferent pathways from the chemosensitive carotid body. To investigate how microglia, a type of immune cell in the brain, respond to an anoxic environment resulting from the administration of NaCN, we studied the effects of blocking the TrkB receptor on this cell-type response. Male Wistar rats were anesthetized, and a dose of NaCN was injected into their carotid sinus to induce anoxia. Prior to the anoxic stimulus, the rats were given an intracerebroventricular (icv) infusion of either K252a, a TrkB receptor inhibitor, BDNF, or an artificial cerebrospinal fluid (aCSF). After the anoxic stimulus, the rats were perfused with paraformaldehyde, and their brains were processed for microglia immunohistochemistry. The results indicated that the anoxic stimulation caused an increase in the number of reactive microglial cells in the hypothalamic arcuate, basolateral amygdala, and dentate gyrus of the hippocampus. However, the infusion of the K252a TrkB receptor inhibitor prevented microglial activation in these regions. [ABSTRACT FROM AUTHOR]

Toxic effluents from cassava processing mills through leaching and percolation are transported into groundwater, which may be detrimental to the health of humans when consumed. Our knowledge on how these toxic effluents are transported into groundwater is limited and has not received the needed attention. The objective of the study is to stimulate groundwater flow and migration pattern of cassava effluents, stimulate the impact of recharge and discharge on the fate of cassava plume migration and, lastly to suggest a remediation techniques. Groundwater modelling system (GMS) software was used for the stimulation of migration of cyanide from the surface into groundwater. The results revealed that transport of Cyanide is considerably influenced by the subsurface geology of the unsaturated zone, groundwater recharge, pumping and dispersion rates, respectively. In a well at the source, a cyanide mass of 3.5 × 105 mg was observed under increased recharge conditions for 7300 days and 7.6 × 104 mg when reduced. Increased pumping rate for 7300 days, cyanide mass of 8.8 × 104 mg was detected and it was 2.6 × 105 mg when reduced. Increased dispersion results in 2.3 × 105 mg and 3.1 × 105 mg when reduced. Of these parameters simulated, recharge has the greatest impact on the transport of cyanide. The effectiveness of using MODFLOW and MT3DMS to understand the way cyanide is transported into groundwater is fully demonstrated. The pump-and treat remediation types is recommended for groundwater resource management and planning.

Introduction Pediatric trauma has long been one of the primary contributors to pediatric mortality. There are multiple cases in the literature involving cyanide (CN) toxicity, carbon monoxide (CO) toxicity, and smoke inhalation with thermal injury, but none in combination with mechanical trauma. Methods In this 45-minute simulation case, emergency medicine residents and fellows were asked to manage a pediatric patient with multiple life-threatening traumatic and metabolic concerns after being extracted from a van accident with a resulting fire. Providers were expected to identify and manage the patient's airway, burns, hemoperitoneum, and CO and CN toxicities. Results Forty learners participated in this simulation, the majority of whom had little prior clinical experience managing the concepts highlighted in it. All agreed or strongly agreed that the case was relevant to their work. After participation, learner confidence in the ability to manage each of the learning objectives was high. One hundred percent of learners felt confident or very confident in managing CO toxicity and completing primary and secondary surveys, while 97% were similarly confident in identifying smoke inhalation injury, preparing for a difficult airway, and managing CN toxicity. Discussion This case was a well-received teaching tool for the management of pediatric trauma and metabolic derangements related to fire injuries. While this specific case represents a rare clinical experience, it is within the scope of expected knowledge for emergency medicine providers and offers the opportunity to practice managing multisystem trauma.

ABSTRACTPseudomonas aeruginosa is a common, biofilm-forming pathogen that exhibits complex pathways of redox metabolism. It produces four different types of terminal oxidases for aerobic respiration, and for one of these, the cbb3-type terminal oxidases, it has the capacity to produce at least 16 isoforms encoded by partially redundant operons. It also produces small-molecule virulence factors that interact with the respiratory chain, including the poison cyanide. Previous studies had indicated a role for cyanide in activating expression of an “orphan” terminal oxidase subunit gene called ccoN4 and that the product contributes to P. aeruginosa cyanide resistance, fitness in biofilms, and virulence, but the mechanisms underlying this process had not been elucidated. Here, we show that the regulatory protein MpaR, which is predicted to be a pyridoxal phosphate-binding transcription factor and is encoded just upstream of ccoN4, controls ccoN4 expression in response to endogenous cyanide. Paradoxically, we find that cyanide production is required to support CcoN4’s contribution to respiration in biofilms. We identify a palindromic motif required for cyanide- and MpaR-dependent expression of ccoN4 and co-expressed adjacent loci. We also characterize the regulatory logic of this region of the chromosome. Finally, we identify residues in the putative cofactor-binding pocket of MpaR, which are required for ccoN4 expression. Together, our findings illustrate a novel scenario in which the respiratory toxin cyanide acts as a signal to control gene expression in a bacterium that produces the compound endogenously.IMPORTANCECyanide is an inhibitor of heme-copper oxidases, which are required for aerobic respiration in all eukaryotes and many prokaryotes. This fast-acting poison can arise from diverse sources, but mechanisms by which bacteria sense it are poorly understood. We investigated the regulatory response to cyanide in the pathogenic bacterium Pseudomonas aeruginosa, which produces cyanide as a virulence factor. Although P. aeruginosa has the capacity to produce a cyanide-resistant oxidase, it relies primarily on heme-copper oxidases and even makes additional heme-copper oxidase proteins specifically under cyanide-producing conditions. We found that the protein MpaR controls expression of cyanide-inducible genes in P. aeruginosa and elucidated the molecular details of this regulation. MpaR contains a DNA-binding domain and a domain predicted to bind pyridoxal phosphate (vitamin B6), a compound that is known to react spontaneously with cyanide. These observations provide insight into the understudied phenomenon of cyanide-dependent regulation of gene expression in bacteria.

ContextHydrogen cyanide and methanethiol are two toxic gases that inhibit mitochondrial cytochrome c oxidase. Cyanide is generated in structural fires and methanethiol is released by decaying organic matter. Current treatments for cyanide exposure do not lend themselves to treatment in the field and no treatment exists for methanethiol poisoning. Sodium tetrathionate (tetrathionate), a product of thiosulfate oxidation, could potentially serve as a cyanide antidote, and, based on its chemical structure, we hypothesized it could react with methanethiol.ResultsWe show that tetrathionate, unlike thiosulfate, reacts directly with cyanide in vitro under physiological conditions, and based on rabbit studies where we monitor cyanide poisoning in real-time, tetrathionate likely reacts directly with cyanide in vivo. We found that tetrathionate administered by intramuscular injection rescues >80% of juvenile, young adult, and old adult mice from exposure to inhaled hydrogen cyanide gas that is >80% lethal. Tetrathionate also rescued young adult rabbits from intravenously administered sodium cyanide. Tetrathionate was reasonably well-tolerated by mice and rats, yielding a therapeutic index of ∼5 in juvenile and young adult mice, and ∼3.3 in old adult mice; it was non-mutagenic in Chinese Hamster ovary cells and by the Ames bacterial test. We found by gas chromatography-mass spectrometry that both tetrathionate and thiosulfate react with methanethiol to generate dimethyldisulfide, but that tetrathionate was much more effective than thiosulfate at recovering intracellular ATP in COS-7 cells and rescuing mice from a lethal exposure to methanethiol gas.ConclusionWe conclude that tetrathionate has the potential to be an effective antidote against cyanide and methanethiol poisoning.

Cyanide (CN) is a serious concern in industrial and goldmine wastewater. Strict regulatory standards have been established by various agencies due to the detrimental effects that CN has on human health. Therefore, before discharge to water bodies or land, it is essential to create a sustainable model for the safe removal of CN. Carbon-based materials are well known for their adsorption and oxidation features, which can be conducive to CN removal. This paper reviews the relevant literature on the application of modified and unmodified carbon-based materials to CN removal in water; these materials include activated carbon (AC), graphene, graphene oxide (GO), and carbon nanotubes (CNTs). Moreover, CN removal mechanisms and photocatalytic removal of CN are comprehensively discussed, with a particular emphasis on modifying carbon-based materials. It has been observed that adding various elements to carbon-based materials improves their surface area, functional groups, CN adsorption capacity, and pore volume. Impacts of operational parameters, isotherm models, kinetics, and types of carbon-based materials are also outlined. This study provides insight into the real-scale applicability of carbon-based materials for CN removal from waters. Moreover, this review indicates that essential work on CN removal using carbon-based materials is still needed. Future research should focus on developing modified carbon-based materials to encourage multidisciplinary research. The most crucial gap in the literature is that the studies have been performed on a lab scale. Therefore, further pilot and real-scale applications should be conducted. Overall, the cost assessment, environmental effects, and human health risks of carbon-based materials should be studied in future research to achieve a realistic perspective on applicability on an industrial scale.

Simple and efficient sample pretreatment methods are important for analysis and detection of chemical warfare agents (CWAs) in environmental and biological samples. Despite many commercial materials or reagents that have been already applied in sample preparation, such as SPE columns, few materials with specificity have been utilized for purification or enrichment. In this study, ionic magnetic mesoporous nanomaterials such as poly(4-VB)@M-MSNs (magnetic mesoporous silicon nanoparticles modified by 4-vinyl benzene sulfonic acid) and Co2+@M-MSNs (magnetic mesoporous silicon nanoparticles modified by cobalt ions) with high absorptivity for ethanol amines (EAs, nitrogen mustard degradation products) and cyanide were successfully synthesized. The special nanomaterials were obtained by modification of magnetic mesoporous particles prepared based on co-precipitation using -SO3H and Co2+. The materials were fully characterized in terms of their composition and structure. The results indicated that poly(4-VB)@M-MSNs or Co2+@M-MSNs had an unambiguous core-shell structure with a BET of 341.7 m2·g−1 and a saturation magnetization intensity of 60.66 emu·g−1 which indicated the good thermal stability. Poly(4-VB)@M-MSNs showed selective adsorption for EAs while the Co2+@M-MSNs were for cyanide, respectively. The adsorption capacity quickly reached the adsorption equilibrium within the 90 s. The saturated adsorption amounts were MDEA = 35.83 mg·g−1, EDEA = 35.00 mg·g−1, TEA = 17.90 mg·g−1 and CN−= 31.48 mg·g−1, respectively. Meanwhile, the adsorption capacities could be maintained at 50–70% after three adsorption–desorption cycles. The adsorption isotherms were confirmed as the Langmuir equation and the Freundlich equation, respectively, and the adsorption mechanism was determined by DFT calculation. The adsorbents were applied for enrichment of targets in actual samples, which showed great potential for the verification of chemical weapons and the destruction of toxic chemicals.

Metal–organic frameworks (MOFs) are frequently utilized as sensing materials. Unfortunately, the low conductivity of MOFs hinder their further application in electrochemical determination. To overcome this limitation, a novel modification strategy for MOFs was proposed, establishing an electrochemical determination method for cyanides in Baijiu. Co and Ni were synergistically used as the metal active centers, with meso−Tetra(4−carboxyphenyl)porphine (TCPP) and Ferrocenecarboxylic acid (Fc−COOH) serving as the main ligands, synthesizing Ni/Co−MOF−TCPP−Fc through a hydrothermal method. The prepared MOF exhibited improved conductivity and stable ratio signals, enabling rapid and sensitive determination of cyanides. The screen−printed carbon electrodes (SPCE) were suitable for in situ and real−time determination of cyanide by electrochemical sensors due to their portability, low cost, and ease of mass production. A logarithmic linear response in the range of 0.196~44 ng/mL was demonstrated by this method, and the limit of detection (LOD) was 0.052 ng/mL. Compared with other methods, the sensor was constructed by a one−step synthesis method, which greatly simplifies the analysis process, and the determination time required was only 4 min. During natural cyanide determinations, recommended readouts match well with GC−MS with less than 5.9% relative error. Moreover, this electrochemical sensor presented a promising method for assessing the safety of cyanides in Baijiu.

Purines are the building blocks of DNA/RNA, energy substrates, and cofactors. Purine metabolites, including ATP, GTP, NADH, and coenzyme A, are essential molecules in diverse biological processes such as energy metabolism, signal transduction, and enzyme activity. When purine levels increase, excess purines are either recycled to synthesize purine metabolites or catabolized to the end product uric acid. Purine catabolism increases during states of low oxygen tension (hypoxia and ischemia), but this metabolic pathway is incompletely understood in the context of histotoxic hypoxia (i.e., inhibition of oxygen utilization despite normal oxygen tension). In rabbits exposed to cyanide—a classical histotoxic hypoxia agent—we demonstrated significant increases in several concordant metabolites in the purine catabolic pathway (including plasma levels of uric acid, xanthosine, xanthine, hypoxanthine, and inosine) via mass spectrometry-based metabolite profiling. Pharmacological inhibition of the purine catabolic pathway with oxypurinol mitigated the deleterious effects of cyanide on skeletal muscle cytochrome c oxidase redox state, measured by non-invasive diffuse optical spectroscopy. Finally, plasma uric acid levels correlated strongly with those of lactic acid, an established clinical biomarker of cyanide exposure, in addition to a tissue biomarker of cyanide exposure (skeletal muscle cytochrome c oxidase redox state). Cumulatively, these findings not only shed light on the in vivo role(s) of cyanide but also have implications in the field of medical countermeasure (MCM) development.

A novel indolium-based fluorescent probe for the detection of CN− was developed based on the conjugation of 1, 2, 3, 3-Tetramethyl-3H-indolium iodide and 2-acetyl benzothiophene. The introduction of external CN− caused a nucleophilic attack to the quaternary amine salt structure in the probe and resulted in the departure of iodide ions and the steric rotation of the index salt group, which caused fluorescence quenching. The titration experiments showed that the probe had rapid qualitative and quantitative analysis capabilities for CN−. Moreover, the relevant biocompatibility experiments also demonstrated the potential application value of the probe.

The release of cyanide from cyanogenic precursors is the central core of the plant defences based on the cyanogenesis process. Although cyanide is formed as a coproduct of some metabolic routes, its production is mostly due to the degradation of cyanohydrins originating from cyanogenic glycosides in cyanogenic plants and the 4-OH-ICN route in Brassicaceae. Cyanohydrins are then hydrolysed in a reversible reaction generating cyanide, being both, cyanohydrins and cyanide, toxic compounds with potential defensive properties against pests and pathogens. Based on the production of cyanogenic-derived molecules in response to the damage caused by herbivore infestation, in this review, we compile the actual knowledge of plant cyanogenic events in the plant–pest context. Besides the defensive potential, the mode of action, and the targets of the cyanogenic compounds to combat phytophagous insects and acari, special attention has been paid to arthropod responses and the strategies to overcome the impact of cyanogenesis. Physiological and behavioural adaptations, as well as cyanide detoxification by β-cyanoalanine synthases, rhodaneses, and cyanases are common ways of phytophagous arthropods defences against the cyanide produced by plants. Much experimental work is needed to further understand the complexities and specificities of the defence–counter-defence system to be applied in breeding programs.

Molecular studies about cyanide biodegradation have been mainly focused on the hydrolytic pathways catalyzed by the cyanide dihydratase CynD or the nitrilase NitC. In some Pseudomonas strains, the assimilation of cyanide has been linked to NitC, such as the cyanotrophic model strain Pseudomonas pseudoalcaligenes CECT 5344, which has been recently reclassified as Pseudomonas oleovorans CECT 5344. In this work, a phylogenomic approach established a more precise taxonomic position of the strain CECT 5344 within the species P. oleovorans. Furthermore, a pan-genomic analysis of P. oleovorans and other species with cyanotrophic strains, such as P. fluorescens and P. monteilii, allowed for the comparison and identification of the cioAB and mqoAB genes involved in cyanide resistance, and the nitC and cynS genes required for the assimilation of cyanide or cyanate, respectively. While cyanide resistance genes presented a high frequency among the analyzed genomes, genes responsible for cyanide or cyanate assimilation were identified in a considerably lower proportion. According to the results obtained in this work, an in silico approach based on a comparative genomic approach can be considered as an agile strategy for the bioprospection of putative cyanotrophic bacteria and for the identification of new genes putatively involved in cyanide biodegradation.

The investigation of the coordination chemistry of rare-earth metal complexes with cyanide ligands led to the isolation and crystallographic characterization of the Ln III cyano-tri-phenyl-borate complexes di-chlorido-(cyano-tri-phenyl-borato-κN)tetra-kis-(tetra-hydro-furan-κO)lanthanide(III), [LnCl2(C19H15BN)(C4H8O)4] [lanthanide (Ln) = dysprosium (Dy) and yttrium Y)] from reactions of LnCl3, KCN, and NaBPh4. Attempts to independently synthesize the tetra-ethyl-ammonium salt of (NCBPh3)- from BPh3 and [NEt4][CN] in THF yielded crystals of the phenyl-substituted cyclic borate, tetra-ethyl-aza-nium 2,2,4,6-tetra-phenyl-1,3,5,2λ4,4,6-trioxatriborinan-2-ide, C8H20N+·C24H20B3O3 - or [NEt4][B3(μ-O)3(C6H5)4]. The mechanochemical reaction of BPh3 and [NEt4][CN] without solvent produced crystals of tetra-ethyl-aza-nium cyano-diphenyl-λ4-boranyl di-phenyl-borinate, C8H20N+·C25H20B2NO- or [NEt4][NCBPh2(μ-O)BPh2]. Reaction of BPh3 and KCN in THF in the presence of 2.2.2-cryptand (crypt) led to a crystal of bis-[(2.2.2-cryptand)potassium] 2,2,4,6-tetra-phenyl-1,3,5,2λ4,4,6-trioxatriborinan-2-ide cyano-methyl-diphenyl-borate tetra-hydro-furan disolvate, 2C18H36KN2O6 +·C24H20B3O3 -·C14H13BN-·2C4H8O or [K(crypt)]2[B3(μ-O)3(C6H5)4][NCBPh2Me]·2THF. The [NCBPh2(μ-O)BPh2]1- and (NCBPh2Me)1- anions have not been structurally characterized previously. The structure of 1-Y was refined as a two-component twin with occupancy factors 0.513 (1) and 0.487 (1). In 4, one solvent mol-ecule was disordered and included using multiple components with partial site-occupancy factors.

IntroductionCyanide is a deadly poison, particularly with oral exposure where larger doses can occur before symptoms develop. Prior studies and multiple governmentagencies highlight oral cyanide as an agent with the potential for use in a terrorist attack. Currently, there are no FDA approved antidotes specific to oralcyanide. An oral countermeasure that can neutralize and prevent absorption of cyanide from the GI tract after oral exposure is needed. Our objective was toevaluate the efficacy of oral sodium thiosulfate on survival and clinical outcomes in a large, swine model of severe cyanide toxicity.MethodsSwine (45-55kg) were instrumented, sedated, and stabilized. Potassium cyanide (8 mg/kg KCN) in saline was delivered as a one-time bolus via an orogastric tube. Three minutes after cyanide, animals randomized to the treatment group received sodium thiosulfate (510 mg/kg, 3.25 M solution) via orogastric tube. Our primary outcome was survival at 60 minutes after exposure. We compared survival between groups by log-rank, Mantel-Cox analysis and trended labs and vital signs.ResultsAt baseline and time of treatment all animals had similar weights, vital signs, and laboratory values. Survival at 60 min was 100% in treated animals compared to 0% in the control group (p=0.0027). Animals in the control group became apneic and subsequently died by 35.0 min (20.2,48.5) after cyanide exposure. Mean arterial pressure was significantly higher in the treatment group compared to controls (p=0.008). Blood lactate (p=0.02) and oxygen saturation (p=0.02) were also significantly different between treatment and control groups at study end.ConclusionOral administration of sodium thiosulfate improved survival, blood pressure, respirations, and blood lactate concentrations in a large animal model of acute oral cyanide toxicity.

PT. Aneka Tambang conducts gold processing using NaCN reagents, then from the gold processing process produces waste containing cyanide which can cause damage to the environment. One method used to reduce cyanide concentrations is the Degussa method. The Degussa method is a method to degrade free cyanide in waste by using H2O2 and Cu2+ ions as a catalyst source so that it becomes a harmless cyanide compound (cyanate ion). The purpose of the study was to determine the ability of hydrogen peroxide and determine the effective concentration of copper sulfate in degrading cyanide in the Degussa process and determine the level of stability of hydrogen peroxide oxidizers in the open air. Sample testing was carried out by varying the H2O2 retrieval time, variations in H2O2 dilution factor and copper sulfate concentration variations, then the sample was stirred with a jartes stirrer for 15 minutes. Cyanide is determined by spectrophotometer, the absorbance obtained is fed into the linear regression equation so that the final free cyanide concentration is obtained. From the experiment, it can be concluded that the concentration of cyanide degradation is effectively obtained when hydrogen peroxide and copper sulfate that have been mixed in the mixing tank are right out of use.

Cyanide is used in several industries but is widely used for gold extraction due to its ability to complex and stabilize gold ions. The waste generated from this process is of great volume because of low ore grades that requires more processing areas. Also, it is highly toxic due to cyanide being a contaminant of animal life and the environment. The mining sector can recycle the effluents generated in their processes, however, this can affect the gold extraction and treatment methods. There are legal laws that define cyanide levels in effluents for disposal in water bodies. Methodologies for reaching these levels include oxidation degradation processes, physical-chemical, biological processes, adsorption, photocatalysis, among others. In this present review, the use of cyanide in gold mining and some of these methodologies for removing cyanide in effluents generated by gold processing are evaluated.

In the process of gold ores leaching by glycine and cyanide, the interactions between glycine and cyanide with metals are not well understood and there is little research in this area. The characterization of gold and copper complexes in the cyanide-glycine system by UV-Vis spectroscopy method is studied. Job’s method of continuous variation was applied to ascertain the stoichiometry composition of the complexes. The results showed that in the glycine-gold-copper system, although the stability constant of the gold-glycine complex is higher, the dominant species formed is the copper-glycine complex. In the cyanide-gold-copper system, gold forms complexes with cyanide and to a lesser extent glycine, which agrees with their stability constants. If the cyanide and glycine ligands are added to a gold solution, the dominant species in the system is the gold-cyanide complex. In the cyanide-glycine-copper system, the dominant species in the system is the copper-glycine complex. When cyanide and glycine ligands are added to a gold-copper solution, the dominant species in the system are the copper-glycine and the gold-cyanide complexes. [ABSTRACT FROM AUTHOR]

The use of thiosulfate to extract gold from refractory ores is promising because of its non-toxicity and high selectivity. Sulfide minerals (i.e., pyrite, arsenopyrite, chalcopyrite), major gold carriers in refractory gold ores, however, hinder gold extraction due to the high consumption of a lixiviant. In this study, a new method to improve gold extraction from sulfide bearing gold ores is proposed based on the model experiments using a mixture of gold powder and arsenopyrite-bearing sulfide (HAsBS) ore. The effects of HAsBS ore on gold leaching in ammonium thiosulfate solutions were investigated, and it was found that gold extraction in the presence of HAsBS ore was suppressed because of the unwanted decomposition of thiosulfate on the surface of sulfide minerals. To improve gold extraction in the presence of the sulfide minerals, this study investigated the effects of the pretreatment of HAsBS ore using ammonium solutions containing cupric ions and confirmed that HAsBS ore was oxidized in the pretreatment and its surface was covered by the oxidation products. As a result, thiosulfate consumption was minimized in the subsequent gold leaching step using ammonium thiosulfate, resulting in an improvement in gold extraction from 10% to 79%. [ABSTRACT FROM AUTHOR]

Chemical agents have been utilized for centuries in warfare and pose a health threat to civilians and military personnel during armed conflict. Despite treaties and regulations against their use, chemical agent exposure remains a threat and measures to understand their effects and countermeasures for systemic and organ-specific health are needed. Many of these agents have ocular complications, both acute and chronic. This mini-review focuses on key chemical agents including vesicants (mustards, lewisite), nerve agents (sarin, VX), knockdown gasses (hydrogen cyanide), and caustics (hydrofluoric acid). Their ophthalmic manifestations and appropriate treatment are emphasized. Acute interventions include removal of the source and meticulous decontamination, as well as normalization of pH to 7.2–7.4 if alteration of the ocular pH is observed. Besides vigorous lavage, acute therapies may include topical corticosteroids and non-steroid anti-inflammatory therapies. Appropriate personal protective equipment (PPE) and strict donning and doffing protocols to avoid healthcare provider exposure are also paramount in the acute setting. For more severe disease, corneal transplantation, amniotic membrane graft, and limbal stem cell transplantation may be needed. Orbital surgery may be required in patients in whom cicatricial changes of the ocular surface have developed, leading to eyelid malposition. Multidisciplinary care teams are often required to handle the full spectrum of findings and consequences associated with emerging chemical threats.

Cyanide (CN) is a serious concern in industrial and goldmine wastewater. Strict regulatory standards have been established by various agencies due to the detrimental effects that CN has on human health. Therefore, before discharge to water bodies or land, it is essential to create a sustainable model for the safe removal of CN. Carbon-based materials are well known for their adsorption and oxidation features, which can be conducive to CN removal. This paper reviews the relevant literature on the application of modified and unmodified carbon-based materials to CN removal in water; these materials include activated carbon (AC), graphene, graphene oxide (GO), and carbon nanotubes (CNTs). Moreover, CN removal mechanisms and photocatalytic removal of CN are comprehensively discussed, with a particular emphasis on modifying carbon-based materials. It has been observed that adding various elements to carbon-based materials improves their surface area, functional groups, CN adsorption capacity, and pore volume. Impacts of operational parameters, isotherm models, kinetics, and types of carbon-based materials are also outlined. This study provides insight into the real-scale applicability of carbon-based materials for CN removal from waters. Moreover, this review indicates that essential work on CN removal using carbon-based materials is still needed. Future research should focus on developing modified carbon-based materials to encourage multidisciplinary research. The most crucial gap in the literature is that the studies have been performed on a lab scale. Therefore, further pilot and real-scale applications should be conducted. Overall, the cost assessment, environmental effects, and human health risks of carbon-based materials should be studied in future research to achieve a realistic perspective on applicability on an industrial scale. [ABSTRACT FROM AUTHOR]

Seed germination is the complex adaptive trait of higher plants influenced by a large number of genes and environmental factors. Numerous studies have been performed to better understand how germination is controlled by various environmental factors and applied chemicals, such as cyanide. However, still very little is known about the molecular mechanisms of how extrinsic signals regulate seed germination. Our and previous studies found that non-lethal cyanide treatment promotes seed germination, but the regulatory mechanism is unclear. In this study, we found that a low concentration of cyanide pretreatment significantly enhanced the expression of endo-β-mannanase 5 (MAN5) gene in Arabidopsis thaliana, and the mutation of this gene impaired cyanide-mediated seed germination. In contrast, overexpression of MAN5 gene enhanced Arabidopsis seed germination ability under both normal and salt stress conditions. Further studies showed that the expression of the MAN5 gene was negatively regulated by ABA insensitive 5 (ABI5); In abi5 mutant seeds, the expression of the MAN5 gene was increased and the seed germination rate was accelerated. Additionally, cyanide pretreatment markedly reduced the gene expression of ABI5 in Arabidopsis seeds. Taken together, our data support the involvement of MAN5 as a key gene in cyanide-mediated seed germination and confirm the role of ABI5 as a critical negative factor involved in cyanide-regulated MAN5 gene expression. [ABSTRACT FROM AUTHOR]

Sodium Nitroprusside has been approved since 1974 as a medication for hypertensive crises. However, there has been ongoing controversy regarding its potential toxicity. Cyanide toxicity is a rare complication of Sodium Nitroprusside, which can be challenging to diagnose in critically ill patients. Risk factors include prolonged infusions and high doses; hence it is suggested that the dose should not exceed 2 µg/kg/min. Here, we present the case of a 49-year-old patient who entered the emergency department after a cerebrovascular event and a hypertensive emergency that required Sodium Nitroprusside infusion, followed by signs and symptoms suggestive of toxicity. Neurological changes were predominant among these symptoms, and the patient was managed with sodium thiosulfate, resulting in a good response. The objective of this case report is to raise awareness among healthcare professionals about the need for appropriate use of Sodium Nitroprusside and the importance of suspecting toxicity in patients with risk factors. [ABSTRACT FROM AUTHOR]