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1.
Chem Res Toxicol ; 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39119730

RESUMO

Bromo-DragonFLY is a synthetic new psychoactive substance (NPS) that has gained attention due to its powerful and long-lasting hallucinogenic effects, legal status, and widespread availability. This study aimed to use various in silico toxicology methods to predict key toxicological parameters for Bromo-DragonFLY, including acute toxicity (LD50), genotoxicity, cardiotoxicity, health effects, and the potential for endocrine disruption. The results indicate significant acute toxicity with noticeable variations across different species, a low likelihood of genotoxic potential suggesting potential DNA damage, and a notable risk of cardiotoxicity associated with inhibition of the hERG channel. Evaluation of endocrine disruption suggests a low probability of Bromo-DragonFLY interacting with the estrogen receptor α (ER-α), indicating minimal estrogenic activity. These insights from in silico investigations are important for advancing our understanding of this NPS in forensic and clinical toxicology. These initial toxicological examinations establish a foundation for future research efforts and contribute to developing risk assessment and management strategies for using and misusing NPS.

2.
Int J Mol Sci ; 25(13)2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38999996

RESUMO

Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy are powerful analytical techniques widely used separately in different fields of study. Integrating these two powerful spectroscopic techniques into one device represents a groundbreaking advance in multimodal imaging. This new combination which merges the molecular vibrational information from Raman spectroscopy with the ability of FTIR to study polar bonds, creates a unique and complete analytical tool. Through a detailed examination of the microscope's operation and case studies, this article illustrates how this integrated analytical instrument can provide more thorough and accurate analysis than traditional methods, potentially revolutionising analytical sample characterisation. This article aims to present the features and possible uses of a unified instrument merging FTIR and Raman spectroscopy for multimodal imaging. It particularly focuses on the technological progress and collaborative benefits of these two spectroscopic techniques within the microscope system. By emphasising this approach's unique benefits and improved analytical capabilities, the authors aim to illustrate its applicability in diverse scientific and industrial sectors.


Assuntos
Microscopia , Imagem Multimodal , Análise Espectral Raman , Análise Espectral Raman/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Imagem Multimodal/métodos , Imagem Multimodal/instrumentação , Microscopia/métodos , Microscopia/instrumentação , Humanos
3.
Int J Mol Sci ; 25(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38612865

RESUMO

In recent years, the extensive exploration of Gold Nanoparticles (AuNPs) has captivated the scientific community due to their versatile applications across various industries. With sizes typically ranging from 1 to 100 nm, AuNPs have emerged as promising entities for innovative technologies. This article comprehensively reviews recent advancements in AuNPs research, encompassing synthesis methodologies, diverse applications, and crucial insights into their toxicological profiles. Synthesis techniques for AuNPs span physical, chemical, and biological routes, focusing on eco-friendly "green synthesis" approaches. A critical examination of physical and chemical methods reveals their limitations, including high costs and the potential toxicity associated with using chemicals. Moreover, this article investigates the biosafety implications of AuNPs, shedding light on their potential toxic effects on cellular, tissue, and organ levels. By synthesizing key findings, this review underscores the pressing need for a thorough understanding of AuNPs toxicities, providing essential insights for safety assessment and advancing green toxicology principles.


Assuntos
Ouro , Nanopartículas Metálicas , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Indústrias , Tecnologia
4.
Arch Toxicol ; 98(6): 1809-1825, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38493428

RESUMO

The idea of this study was the estimation of the theoretical acute toxicity (t-LD50, rat, oral dose) of organophosphorus-based chemical warfare agents from the G-series (n = 12) using different in silico methods. Initially identified in Germany, the G-type nerve agents include potent compounds such as tabun, sarin, and soman. Despite their historical significance, there is a noticeable gap in acute toxicity data for these agents. This study employs qualitative (STopTox and AdmetSAR) and quantitative (TEST; CATMoS; ProTox-II and QSAR Toolbox) in silico methods to predict LD50 values, offering an ethical alternative to animal testing. Additionally, we conducted quantitative extrapolation from animals, and the results of qualitative tests confirmed the acute toxicity potential of these substances and enabled the identification of toxicophoric groups. According to our estimations, the most lethal agents within this category were GV, soman (GD), sarin (GB), thiosarin (GBS), and chlorosarin (GC), with t-LD50 values (oral administration, extrapolated from rat to human) of 0.05 mg/kg bw, 0.08 mg/kg bw, 0.12 mg/kg bw, 0.15 mg/kg bw, and 0.17 mg/kg bw, respectively. On the contrary, compounds with a cycloalkane attached to the phospho-oxygen linkage, specifically methyl cyclosarin and cyclosarin, were found to be the least toxic, with values of 2.28 mg/kg bw and 3.03 mg/kg bw. The findings aim to fill the knowledge gap regarding the acute toxicity of these agents, highlighting the need for modern toxicological methods that align with ethical considerations, next-generation risk assessment (NGRA) and the 3Rs (replacement, reduction and refinement) principles.


Assuntos
Substâncias para a Guerra Química , Simulação por Computador , Compostos Organofosforados , Relação Quantitativa Estrutura-Atividade , Substâncias para a Guerra Química/toxicidade , Animais , Dose Letal Mediana , Compostos Organofosforados/toxicidade , Ratos , Administração Oral , Sarina/toxicidade , Testes de Toxicidade Aguda/métodos , Soman/toxicidade , Medição de Risco/métodos
5.
Arch Toxicol ; 98(5): 1469-1483, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38441627

RESUMO

The emergence of Novichok agents, potent organophosphorus nerve agents, has spurred the demand for advanced analytical methods and toxicity assessments as a result of their involvement in high-profile incidents. This study focuses on the degradation products of Novichok agents, particularly their potential toxic effects on biological systems. Traditional in vivo methods for toxicity evaluation face ethical and practical constraints, prompting a shift toward in silico toxicology research. In this context, we conducted a comprehensive qualitative and quantitative analysis of acute oral toxicity (AOT) for Novichok degradation products, using various in silico methods, including TEST, CATMoS, ProTox-II, ADMETlab, ACD/Labs Percepta, and QSAR Toolbox. Adopting these methodologies aligns with the 3Rs principle, emphasising Replacement, Reduction, and Refinement in the realm of toxicological studies. Qualitative assessments with STopTox and admetSAR revealed toxic profiles for all degradation products, with predicted toxicophores highlighting structural features responsible for toxicity. Quantitative predictions yielded varied estimates of acute oral toxicity, with the most toxic degradation products being EOPAA, MOPGA, MOPAA, MPGA, EOPGA, and MPAA, respectively. Structural modifications common to all examined hydrolytic degradation products involve substituting the fluorine atom with a hydroxyl group, imparting consequential effects on toxicity. The need for sophisticated analytical techniques for identifying and quantifying Novichok degradation products is underscored due to their inherent reactivity. This study represents a crucial step in unravelling the complexities of Novichok toxicity, highlighting the ongoing need for research into its degradation processes to refine analytical methodologies and fortify readiness against potential threats.


Assuntos
Agentes Neurotóxicos , Organofosfatos
6.
Ecotoxicol Environ Saf ; 272: 116018, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38325275

RESUMO

Nerve agents (G- and V-series) are a group of extremely toxic organophosphorus chemical warfare agents that we have had the opportunity to encounter many times on a massive scale (Matsumoto City, Tokyo subway and Gulf War). The threat of using nerve agents in terrorist attacks or military operations is still present, even with establishing the Chemical Weapons Convention as the legal framework. Understanding their environmental sustainability and health risks is critical to social security. Due to the risk of contact with dangerous nerve agents and animal welfare considerations, in silico methods were used to assess hydrolysis and biodegradation safely. The environmental fate of the examined nerve agents was elucidated using QSAR models. The results indicate that the investigated compounds released into the environment hydrolyse at a different rate, from extremely fast (<1 day) to very slow (over a year); V-agents undergo slower hydrolysis compared to G-agents. V-agents turned out to be relatively challenging to biodegrade, the ultimate biodegradation time frame of which was predicted as weeks to months, while for G-agents, the overwhelming majority was classified as weeks. In silico methods for predicting various parameters are critical to preparing for the forthcoming application of nerve agents.


Assuntos
Substâncias para a Guerra Química , Agentes Neurotóxicos , Animais , Substâncias para a Guerra Química/análise , Substâncias para a Guerra Química/química , Substâncias para a Guerra Química/toxicidade , Agentes Neurotóxicos/toxicidade , Hidrólise , Tóquio
7.
Arch Toxicol ; 98(1): 267-275, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38051368

RESUMO

Nerve agents are organophosphate chemical warfare agents that exert their toxic effects by irreversibly inhibiting acetylcholinesterase, affecting the breakdown of the neurotransmitter acetylcholine in the synaptic cleft. Due to the risk of exposure to dangerous nerve agents and for animal welfare reasons, in silico methods have been used to assess acute toxicity safely. The next-generation risk assessment (NGRA) is a new approach for predicting toxicological parameters that can meet modern requirements for toxicological research. The present study explains the acute toxicity of the examined V-series nerve agents (n = 9) using QSAR models. Toxicity Estimation Software Tool (ver. 4.2.1 and ver. 5.1.2), QSAR Toolbox (ver. 4.6), and ProTox-II browser application were used to predict the median lethal dose. The Simplified Molecular Input Line Entry Specification (SMILES) was the input data source. The results indicate that the most deadly V-agents were VX and VM, followed by structural VX analogues: RVX and CVX. The least toxic turned out to be V-sub x and Substance 100A. In silico methods for predicting various parameters are crucial for filling data gaps ahead of experimental research and preparing for the upcoming use of nerve agents.


Assuntos
Substâncias para a Guerra Química , Agentes Neurotóxicos , Compostos Organotiofosforados , Animais , Substâncias para a Guerra Química/toxicidade , Substâncias para a Guerra Química/química , Agentes Neurotóxicos/toxicidade , Agentes Neurotóxicos/química , Acetilcolinesterase/metabolismo , Compostos Organotiofosforados/toxicidade
8.
Toxics ; 11(9)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37755734

RESUMO

Poisoning and overdose are very important aspects in medicine and toxicology. Chemical weapons pose a threat to civilians, and emergency medicine principles must be followed when dealing with patients who have been poisoned or overdosed. Antidotes have been used for centuries and modern research has led to the development of new antidotes that can accelerate the elimination of toxins from the body. Although some antidotes have become less relevant due to modern intensive care techniques, they can still save lives or reduce the severity of toxicity. The availability of antidotes is crucial, especially in developing countries where intensive care facilities may be limited. This article aims to provide information on specific antidotes, their recommended uses, and potential risks and new uses. In the case of poisoning, supportive therapies are most often used; however, in many cases, the administration of an appropriate antidote saves the patient's life. In this review, we reviewed the literature on selected antidotes used in the treatment of poisonings. We also characterised the antidotes (bio)chemically. We described the cases in which they are used together with the dosage recommendations. We also analysed the mechanisms of action. In addition, we described alternative methods of using a given substance as a drug, an example of which is N-acetylcysteine, which can be used in the treatment of COVID-19. This article was written as part of the implementation of the project of the Polish Ministry of Education and Science, "Toxicovigilance, poisoning prevention, and first aid in poisoning with xenobiotics of current clinical importance in Poland", grant number SKN/SP/570184/2023.

9.
Sci Rep ; 13(1): 14172, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37644112

RESUMO

6-Thioguanine is an immunosuppressive drug, an analogue of guanine, applied to treat acute leukemia and inflammatory bowel disease. Excessive use of 6-thioguanine during clinical treatment may cause side effects. Moreover, providing a dose too low will be ineffective. Therefore, there is a critical need for a rapid, selective and routine approach to quantifying 6-thioguanine in body fluids to support a clinical application. A fully validated HPLC method has been developed to determine 6-thioguanine in whole blood samples using 5-bromouracil as an internal standard. 6-Thioguanine nucleotides were released from erythrocytes by perchloric acid, and then hydrolysed at 100 °C to the parent thiopurine, 6-thioguanine. The following validation parameters of the method were determined: specificity/selectivity, linearity range (479-17,118 ng/mL, R > 0.992), limits of detection (150 ng/mL) and quantification (479 ng/mL), accuracy (- 5.6 < Bias < 14.7), repeatability (CV 1.30-3.24%), intermediate precision (CV 4.19-5.78%), extraction recovery (79.1-103.6%) and carryover. Furthermore, the stability of the drug in whole blood samples under various storage conditions was investigated. The suggested method is suitable for determining 6-thioguanine in whole blood erythrocyte samples for drug level monitoring, thus correct dosing.


Assuntos
Líquidos Corporais , Tioguanina , Cromatografia Líquida de Alta Pressão , Eritrócitos , Bromouracila
10.
Int J Mol Sci ; 24(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37445969

RESUMO

In conventional clinical toxicology practice, the blood level of carboxyhemoglobin is a biomarker of carbon monoxide (CO) poisoning but does not correspond to the complete clinical picture and the severity of the poisoning. Taking into account articles suggesting the relationship between oxidative stress parameters and CO poisoning, it seems reasonable to consider this topic more broadly, including experimental biochemical data (oxidative stress parameters) and patients poisoned with CO. This article aimed to critically assess oxidative-stress-related parameters as potential biomarkers to evaluate the severity of CO poisoning and their possible role in the decision to treat. The critically set parameters were antioxidative, including catalase, 2,2-diphenyl-1-picryl-hydrazyl, glutathione, thiol and carbonyl groups. Our preliminary studies involved patients (n = 82) admitted to the Toxicology Clinical Department of the University Hospital of Jagiellonian University Medical College (Kraków, Poland) during 2015-2020. The poisoning was diagnosed based on medical history, clinical symptoms, and carboxyhemoglobin blood level. Blood samples for carboxyhemoglobin and antioxidative parameters were collected immediately after admission to the emergency department. To evaluate the severity of the poisoning, the Pach scale was applied. The final analysis included a significant decrease in catalase activity and a reduction in glutathione level in all poisoned patients based on the severity of the Pach scale: I°-III° compared to the control group. It follows from the experimental data that the poisoned patients had a significant increase in level due to thiol groups and the 2,2-diphenyl-1-picryl-hydrazyl radical, with no significant differences according to the severity of poisoning. The catalase-to-glutathione and thiol-to-glutathione ratios showed the most important differences between the poisoned patients and the control group, with a significant increase in the poisoned group. The ratios did not differentiate the severity of the poisoning. The carbonyl level was highest in the control group compared to the poisoned group but was not statistically significant. Our critical assessment shows that using oxidative-stress-related parameters to evaluate the severity of CO poisoning, the outcome, and treatment options is challenging.


Assuntos
Intoxicação por Monóxido de Carbono , Humanos , Intoxicação por Monóxido de Carbono/diagnóstico , Intoxicação por Monóxido de Carbono/terapia , Catalase , Carboxihemoglobina/análise , Carboxihemoglobina/metabolismo , Biomarcadores , Estresse Oxidativo , Antioxidantes , Monóxido de Carbono , Glutationa
11.
Sci Total Environ ; 890: 164241, 2023 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-37236459

RESUMO

Novichoks constitute a relatively new class of nerve agents of extreme toxicity that we have had the opportunity to experience three times already. After the first case (Salisbury, UK), a public debate about Novichoks began, which resulted in the realisation of the nature of these chemicals. From a social security point of view, examining their properties, especially toxicological and environmental aspects, are crucial. After the CWC (Chemical Warfare Agent) list update, the candidate structures for the Novichoks may be over 10,000 compounds. It would be extremely laborious to conduct experimental research for each. Understanding their environmental persistence and health hazards is an essential national issue. Moreover, due to the high risk posed by contact with hazardous Novichok substances, in silico research was applied to estimate hydrolysis and biodegradation safely. The present study elucidates, using QSAR models, the environmental fate of the Novichoks studied (n = 17). The results indicate that Novichoks released into the environment hydrolyse at various rates, from extremely fast (<1 day) to very slow (more than a year). Furthermore, ultimate biodegradation from weeks to months is expected for most compounds, which classifies them as relatively difficult biodegradable. Applying reliable in silico methods (QSAR Toolbox and EPI Suite) for predicting various parameters is crucial to prepare for the upcoming usage of Novichoks.


Assuntos
Substâncias para a Guerra Química , Agentes Neurotóxicos , Hidrólise , Organofosfatos/toxicidade , Substâncias para a Guerra Química/toxicidade , Substâncias Perigosas , Relação Quantitativa Estrutura-Atividade , Biodegradação Ambiental
12.
Arch Toxicol ; 97(6): 1691-1700, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37145338

RESUMO

Novichoks represent the fourth generation of chemical warfare agents with paralytic and convulsive effects, produced clandestinely during the Cold War by the Soviet Union. This novel class of organophosphate compounds is characterised by severe toxicity, which, for example, we have already experienced three times (Salisbury, Amesbury, and Navalny's case) as a society. Then the public debate about the true nature of Novichoks began, realising the importance of examining the properties, especially the toxicological aspects of these compounds. The updated Chemical Warfare Agents list registers over 10,000 compounds as candidate structures for Novichoks. Consequently, conducting experimental research for each of them would be a huge challenge. Additionally, due to the enormous risk of contact with hazardous Novichoks, in silico assessments were applied to estimate their toxicity safely. In silico toxicology provides a means of identifying hazards of compounds before synthesis, helping to fill gaps and guide risk minimisation strategies. A new approach to toxicology testing first considers the prediction of toxicological parameters, eliminating unnecessary animal studies. This new generation risk assessment (NGRA) can meet the modern requirements of toxicological research. The present study explains, using QSAR models, the acute toxicity of the Novichoks studied (n = 17). The results indicate that the toxicity of Novichoks varies. The deadliest turned out to be A-232, followed by A-230 and A-234. On the other hand, the "Iranian" Novichok and C01-A038 compounds turned out to be the least toxic. Developing reliable in silico methods to predict various parameters is essential to prepare for the upcoming use of Novichoks.


Assuntos
Substâncias para a Guerra Química , Toxicologia , Animais , Substâncias para a Guerra Química/toxicidade , Substâncias para a Guerra Química/química , Organofosfatos , Dose Letal Mediana , Irã (Geográfico) , Toxicologia/métodos
13.
J Clin Med ; 12(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36983219

RESUMO

Novichoks-organophosphorus compounds belong to the nerve agents group, constituting the fourth generation of chemical warfare agents. The tremendous toxicity of Novichoks is assumed to be several times greater than that of VX, whereas no published experimental research supports this. They were surreptitiously created during the Cold War by the Soviet Union. Novichok's toxic action mechanism consists of the inhibition of acetylcholinesterase activity. The review includes data on treating poisoning caused by OPs which could be used as guidelines for the therapy in case of Novichok exposure and HAZMAT/CBRNE approaches. Novichoks pose a severe threat due to their toxicity; however, there is insufficient information about the identity of A-series nerve agents. Filling in the missing data gaps will accelerate progress in improving protection against Novichoks and developing optimal therapy for treating poisoning casualties. Furthermore, introducing solutions to protect medical personnel in contact with a hazardous substance increases the chances of saving casualties of HAZMAT/CBRNE incidents.

14.
Nutrients ; 15(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36986187

RESUMO

Our study's objective is to evaluate the potential health effects of elemental impurities (Ag, Au, Co, Cr, Cs, Li, Mo, Se, and Sr) found in green tea infusions (Camellia sinensis (L.)). The ICP-MS-based methodology was employed for elemental analysis and a detailed health risk evaluation based on weekly consumption (µg/L of infusion/week). The provisional tolerable weekly intake (PTWI), established by the Joint FAO Expert Committee on infusion/week/month based on existing literature data, was then compared to the subjects with data from the available literature. The exposure of the study items to Co ranged from 0.07904 to 0.85421 µg/day. On the contrary, the ICH (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use) guidelines state that the established permitted daily exposure PDE (oral exposure) for Co is 50 µg/day. The PDE of lithium is around 560 µg/day, and according to our study, the estimated daily exposure of the evaluated products to Li fell between 0.0185 and 0.7170 µg/day. Our research also revealed modest concentrations of Cs (0.399-2.654 µg/L), Mo (0.0113-0.107 µg/L), and Sr (9.848-22.331 µg/L) in infusions. The recognized PDE for molybdenum is approximately 3400 µg/day. Only two samples contained silver, and when considering daily consumption, the predicted daily exposure to Ag is between 4.4994 and 0.03122 µg/day. The amounts of all evaluated elements in a daily dose of green tea infusions should not harm the consumer's health. Further considerations should take aspects, such as constant change and environmental pollution, into account.


Assuntos
Camellia sinensis , Chá , Humanos , Lítio , Molibdênio , Medição de Risco
15.
Int J Mol Sci ; 24(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36982206

RESUMO

In recent years, research on silver nanoparticles (AgNPs) has attracted considerable interest among scientists because of, among other things, their alternative application to well-known medical agents with antibacterial properties. The size of the silver nanoparticles ranges from 1 to 100 nm. In this paper, we review the progress of research on AgNPs with respect to the synthesis, applications, and toxicological safety of AgNPs, and the issue of in vivo and in vitro research on silver nanoparticles. AgNPs' synthesis methods include physical, chemical, and biological routes, as well as "green synthesis". The content of this article covers issues related to the disadvantages of physical and chemical methods, which are expensive and can also have toxicity. This review pays special attention to AgNP biosafety concerns, such as potential toxicity to cells, tissues, and organs.


Assuntos
Nanopartículas Metálicas , Prata , Prata/toxicidade , Prata/química , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química , Antibacterianos/química , Química Verde
16.
Arch Toxicol ; 97(3): 651-661, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36583745

RESUMO

Novichok is the name given to the group of nerve agents created stealthily in the later phases of the Cold War by the Soviet Union. Constitute the fourth generation of chemical warfare agents; like other nerve agents, they are organophosphorus compounds designed to be incurable and undetectable. The mechanism of action is based on the non-competitive and irreversible inhibition of acetylcholinesterase. Due to their enormous toxicity, Novichoks have become attractive targets for terrorists. However, little information is known about the identity of nerve agents. Furthermore, these compounds have never been submitted to the Chemical Weapons Convention. Our article aspires to provide a general overview of Novichoks knowledge. As part of this, we reviewed the available literature data to answer the question, what are Novichoks? In addition to the physical and chemical properties of A-agents, synthesis, mechanism of action, and toxicity of nerve agents were also reviewed. We hope that this review will highlight the tremendous threat posed by nerve agents and will inspire further studies on the interdisciplinary aspects of these compounds.


Assuntos
Substâncias para a Guerra Química , Agentes Neurotóxicos , Agentes Neurotóxicos/química , Acetilcolinesterase , Substâncias para a Guerra Química/química , Organofosfatos , Compostos Organofosforados
17.
Artigo em Inglês | MEDLINE | ID: mdl-36554444

RESUMO

The purpose of our studies is the evaluation of the health risks of the novel elemental impurities (Ag, Au, Co, Cs, Li, Mo, Se, Sr, and V) in mint tea infusions (Mentha piperita L.) available in Poland. For this purpose, we applied ICP-MS-based methodology for content analysis (elemental profile and µg/L of the infusion) and also the specific health risk assessment for a comprehensive assessment. Our strategy was based on weekly intake (µg/L of infusion/week) considering weekly tea consumption. Then, based on the weekly consumption of tea per adult, individuals were compared to the Temporary Tolerated Weekly Intake (PTWI) designated by the Joint FAO Expert Committee on Food Additives (JECFA), and the weekly consumption per body weight (µg/L of infusion/week/bw) was estimated. Daily exposure to Co in the tested products is in a range of 0.093-0.238 µg/day. In comparison, the established PDE (oral exposure) for Co by the ICH guideline (the ICH guideline Q3D (R1), 2019) is 50 µg/day. For lithium, PDE is approximately 560 µg/day and, in our study, the estimated daily exposure for Li in investigated products is in a range of 0.226-2.41 µg/day. Our studies found also low levels of Cs (in a range of 0.0598-0.195 µg/L), Mo (in a range of 0.663-3.261 µg/L), and Sr (0.223-65.842 µg/L) in infusions. For Molybdenum, the established PDE is approximately 3400 µg/day. There are no documents about Sr and Co in the Joint FAO/WHO Expert Committee on Food Additives (JECFA) database and the ICH guideline Q3D (R1). In the case of V, the established PDE is 120 µg/day, and the level of V in analyzed infusions is in a range of 0.284-0.702 µg/L. Silver and gold were present only in a few samples, and the estimated daily exposure for Ag is approximately 0.04575 µg/day for product A and approximately 0.1885 µg/day for product O, except for Au, which is in a range of 0.000356-0.114 µg/L. The estimated daily exposure for Ag is 167 µg/day and, for Au, it is in a range of 8.9 × 105-0.0285 µg/day. It can be concluded that levels of all investigated elements (novel and also traditional elemental impurities) in the daily dose should not threaten the consumer's health after consuming mint tea infusions.


Assuntos
Mentha piperita , Mentha , Adulto , Humanos , Lítio , Polônia , Chá , Medição de Risco/métodos
18.
Proc Natl Acad Sci U S A ; 119(24): e2120083119, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35666870

RESUMO

Human pancreatic islets highly express CD59, which is a glycosylphosphatidylinositol (GPI)-anchored cell-surface protein and is required for insulin secretion. How cell-surface CD59 could interact with intracellular exocytotic machinery has so far not been described. We now demonstrate the existence of CD59 splice variants in human pancreatic islets, which have unique C-terminal domains replacing the GPI-anchoring signal sequence. These isoforms are found in the cytosol of ß-cells, interact with SNARE proteins VAMP2 and SNAP25, colocalize with insulin granules, and rescue insulin secretion in CD59-knockout (KO) cells. We therefore named these isoforms IRIS-1 and IRIS-2 (Isoforms Rescuing Insulin Secretion 1 and 2). Antibodies raised against each isoform revealed that expression of both IRIS-1 and IRIS-2 is significantly lower in islets isolated from human type 2 diabetes (T2D) patients, as compared to healthy controls. Further, glucotoxicity induced in primary, healthy human islets led to a significant decrease of IRIS-1 expression, suggesting that hyperglycemia (raised glucose levels) and subsequent decreased IRIS-1 expression may contribute to relative insulin deficiency in T2D patients. Similar isoforms were also identified in the mouse CD59B gene, and targeted CRISPR/Cas9-mediated knockout showed that these intracellular isoforms, but not canonical CD59B, are involved in insulin secretion from mouse ß-cells. Mouse IRIS-2 is also down-regulated in diabetic db/db mouse islets. These findings establish the endogenous existence of previously undescribed non­GPI-anchored intracellular isoforms of human CD59 and mouse CD59B, which are required for normal insulin secretion.


Assuntos
Processamento Alternativo , Diabetes Mellitus , Antígenos CD59/genética , Antígenos CD59/metabolismo , Diabetes Mellitus/genética , Humanos , Secreção de Insulina , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
20.
J Phys Chem B ; 124(24): 4931-4948, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32407114

RESUMO

Magnetite nanoparticles (MNPs) were synthesized using two distinctly different approaches, co-precipitation (CP) and thermal decomposition (TD), and further surface functionalized with organophosphonic ligands containing different numbers of phosphonic groups. We have shown that it is possible to fabricate flower-like assemblies of MNPs through TD at lower temperatures, whereas CP MNPs formed agglomerates of particles with broad size distribution and irregular shapes. The effect of the organophosphonic ligands on the heating efficiency of the TD and CP MNPs under dual mode stimulation (simultaneous action of AMF and NIR laser radiation) was studied for the first time. It was found that in the case of the cost-effective CP MNP synthesis surface functionalization with chosen phosphonic ligands leads to higher heating efficiency upon laser stimulation, whereas better performance of TD MNPs was found under the action of AMF due to the significant difference of nanoparticle properties. The biocompatibility of surface functionalized MNPs with organophosphonic ligands was evaluated through thorough studies of the metabolic activity of MNPs in normal human foreskin fibroblasts as well as oxidative stress induction and oxidation stress response which has not been previously reported for most of the organophosphonic moieties used in this study.


Assuntos
Nanopartículas de Magnetita , Humanos , Teste de Materiais , Temperatura
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