This study aimed to determine the paraoxonase activity and prooxidant-antioxidant balance in the brain tissue of Wistar rats following subacute treatment with selected K-oximes. Each K-oxime was administered intramuscularly (0.1 LD50/kg) twice per week for four weeks, and 7 days after the last treatment, the paraoxonase activity (PON1), the prooxidant-antioxidant balance (PAB), the levels of superoxide anion radical (O2•-), the concentration of nitrite (NO2-) and the content of free protein thiol groups in the brain homogenates were evaluated. The PON1 and PAB activity were significantly reduced in almost all oxime-treated groups (p < 0.01 and p < 0.001, respectively). The concentrations of O2•- were significantly increased in the obidoxime-, K048-, K074- and K075-treated groups (p < 0.001), while the levels of NO2- was significantly decreased in asoxime-, obidoxime-, K074 and K075-treated rats (p < 0.01, p < 0.001, respectively). The content of Thiol groups was significantly elevated in all oxime-treated groups (p < 0.001). Continuing our previously published data, these results confirmed that applied K-oximes improved the oxidative status and further harmful systemic effects of rats after subacute administration.
- MeSH
- antioxidancia * metabolismus MeSH
- aryldialkylfosfatasa * metabolismus MeSH
- dusitany metabolismus MeSH
- krysa rodu rattus MeSH
- mozek * účinky léků metabolismus enzymologie MeSH
- oximy * farmakologie aplikace a dávkování MeSH
- potkani Wistar MeSH
- sulfhydrylové sloučeniny metabolismus MeSH
- superoxidy metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Sdělení z praxe pojednává o případu těžké methemoglobinemie u kojence způsobeném alimentární otravou dusičnany, jejichž zdrojem byla červená řepa uvařená ve vodě z domácí studny. Klinicky se manifestovala těžkou poruchou vědomí s potřebou umělé plicní ventilace, tachykardií, šedomodrým zbarvením kůže a tmavě modrou barvou sliznic. Laboratorním nálezem byla metabolická acidóza s vysokým laktátem, normální vypočtená saturace kyslíkem při nízké saturaci kyslíkem měřenou pulzním oxymetrem. Diagnóza byla definitivně potvrzena stanovením frakce methemoglobinu, která činila 67 %. Podání antidota (methylenová modř) vedlo k promptnímu zlepšení stavu s rychlou normalizací frakce methemoglobinu.
We present a case report of severe methemoglobinemia in infant caused by poisoning of nitrates from the beetroot cooked in water from private well. It was manifestated by unconsciousness, tachycardia, grey-bluish discoloration of the skin and mucous membranes. The arteficial ventilation was needed. There was metabolic lactate acidosis, normal counted oxygen saturation in blood gases analysis, but low measured oxygen saturation by pulse oxymeter. Diagnosis of methemoglobinemia was clear after confirmation of hight level of methemoglobin in blood (67 %). The child was treated by methylen blue, which had very prompt effect on clinical condition, the level of methemoglobin gradually normalized. We still have to think of the possibility of rare, but easily development of nitrate food poisoning from water and food served to infants.
- MeSH
- antidota farmakologie terapeutické užití MeSH
- Beta vulgaris škodlivé účinky MeSH
- Cucurbita škodlivé účinky MeSH
- dusičnany * otrava MeSH
- dusitany otrava MeSH
- kojenec MeSH
- lidé MeSH
- methemoglobinemie * diagnóza etiologie terapie MeSH
- methylenová modř farmakologie terapeutické užití MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
Na základě údajů v Ph. Eur., v některých dalších nověj- ších lékopisech a v publikovaných experimentálních pracích je navrženo revidovat text Ph. Eur. 2.5.8. V první řadě je třeba specifikovat, která z elektrometrických metod má být k instrumentální indikaci konečného bodu diazotačních titrací v Ph. Eur. použita (nejlépe potenciometrie s platinovou indikační elektrodou). Množství bromidu draselného v roztoku k titraci lze snížit na 1 g, chlazení roztoku před titrací z rámcového postupu vypustit a uvést až v jednotlivých monografiích, pokud bude u některých léčiv k získání přesných a správných výsledků potřebné. Diazotační titraci lze v Ph. Eur. využít ke stanovení obsahu i u některých dalších léčiv.
Based on the data in the Ph. Eur., some other newer pharmacopoeias and published experimental papers propose to revise the text of Ph. Eur. 2.5.8. First, it is necessary to specify which of the electrometric methods should be used to indicate the endpoint of diazotization titrations in Ph. Eur. (preferable potentiometry with a platinum indicating electrode). The amount of potassium bromide in the titration solution may be reduced to 1 g, the cooling of the solution before titration may be omitted from the framework procedure, and it may be specified in individual monographs if necessary to obtain accurate and correct results for some medicines. Diazotization titration can be performed in Ph. Eur. and can also be used to determine the content of some other medicines.
- MeSH
- dusitan sodný MeSH
- farmakopea jako téma MeSH
- léčivé přípravky * analýza MeSH
- lidé MeSH
- potenciometrie metody MeSH
- řízení kvality MeSH
- titrace * MeSH
- Check Tag
- lidé MeSH
- Geografické názvy
- Evropa MeSH
Toxoplasma gondii Nicolle et Manceaux, 1909, the etiologic agent of toxoplasmosis, was considered a clonal population with three distinct genetic lineages (I, II and III); however, sequence analysis of different strains has revealed distinct atypical genotypes. Macrophages are essential for immunity against toxoplasmosis and differential cell regulation may affect the course of the disease. In this context, our study aims to investigate the infection by TgChBrUD2, a highly virulent atypical Brazilian strain of T. gondii, on the activation and polarisation of human macrophages. Human macrophage-like cells obtained from THP-1 cells were infected with TgChBrUD2, RH or ME49 strains of T. gondii to evaluate the impact of parasite infection on macrophage polarisation. Our results indicate that the TgChBrUD2 and ME49 strains of T. gondii induced a classic activation of human macrophages, which was confirmed by the high rate of spindle-shaped macrophages, low amount of urea and increase in the levels of nitrite, as well as the down-regulation of M2-markers. In contrast, RH strain promoted an alternative activation of macrophages. The polarisation of human macrophages towards an M1 subtype mediated by TgChBrUD2 and ME49 strains resulted in a low parasite burden, with high levels of IL-6 and MIF. Finally, the M2 subtype triggered by the RH strain culminated in a lower intracellular proliferation index. We concluded that the atypical (TgChBrUD2) and clonal (ME49) strains are able to elicit an M1 subtype, which results in parasitism control, partially explained by the high levels of IL-6 and MIF produced during the infection by these genotypes. In contrast, the clonal (RH) strain promoted a macrophage polarisation towards an M2 subtype, marked by a high parasite burden, with a weak modulation of pro-inflammatory cytokines. Thus, atypical strains can present different mechanisms of pathogenicity and transmissibility compared to clonal strains, as well as they can use distinct strategies to evade the host's immune response and ensure their survival.
- MeSH
- cytokiny MeSH
- dusitany MeSH
- interleukin-6 MeSH
- lidé MeSH
- makrofágy parazitologie MeSH
- močovina MeSH
- paraziti * MeSH
- Toxoplasma * MeSH
- toxoplazmóza * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Brazílie MeSH
The possibility of N-Nitrosation in the absence of nitrosating agents was studied on model solutions and film coated tablets containing metformin. N-nitrosodimethylamine (NDMA) and N-nitrosation precursors (dimethylamine and nitrites) were determined using previously published fully validated analytical methods. Alternative routes to N-nitrosation were found. Dimethylamine can undergo an oxidation to nitrite in the presence of strong oxidants (e.g., H2O2), as was observed during wastewater treatment in several published works. The resulting nitrite can consecutively act as a nitrosating agent. We proved that the described reaction indeed leads to N-nitrosation (NDMA formation in case of dimethylamine precursor) in model solutions made of dimethylamine and H2O2. An experiment was designed in order to prove those reactions take place in dosage forms. Film coated tablets present a highly heterogenous system with several solid phases and low water activity, which is in stark contrast to the liquid wastewater, where this reaction was originally studied. Despite that, the described reaction took place even in the tablets, but only to a small degree. The amount formed via this alternative route corresponds to less than 10 % of the total formed NDMA. The pH optimum of this alternative route lies in the alkaline range which was confirmed by the determined NDMA concentration in model solutions. The solid phase system (i.e., tablets) was found to behave differently. The addition of Na2CO3 into the tablets during manufacture resulted in tablets without NDMA (cNDMA < LOQ) even in batches spiked with both dimethylamine and H2O2. Thus, adjusting the pH of the solid dosage forms remains a sufficient measure of controlling N-nitrosamines in the product, even in product with limit amounts of oxidating agent (H2O2) and N-nitrosation precursor (dimethylamine).
- MeSH
- dimethylaminy MeSH
- dimethylnitrosamin MeSH
- dusitany * MeSH
- léčivé přípravky MeSH
- nitrosace MeSH
- peroxid vodíku * MeSH
- Publikační typ
- časopisecké články MeSH
The ultra-performance liquid chromatography (UPLC) method, which involves pre-column derivatization of nitrite with 2,3-diaminonaphthalene (DAN) to form 2,3-naphthotriazole (NAT), offers the advantages of easy sample preparation, simple derivatization, stable derivatives, rapid analysis, high sensitivity and specificity and lack of interferences for determining nitrite in pharmaceutical samples. Determination of NAT was performed on a an Acquity UPLC HSS T3 column using a gradient elution of 0.1% formic acid with acetonitrile at flow rate of 0.4 mL/min and temperature at 45 °C. The single-quadrupole mass detector was operated in the positive ion mode. Quadrupole mass analyser was employed in selected ion monitoring mode using a target ion at m/z = 170 as [M+H]+. The UPLC-MS method was validated as per International Council on Harmonization (ICH) guidelines in terms of linearity, limit of detection, limit of quantification, selectivity, accuracy, precision, intermediate precision and stability. The UPLC-MS method was demonstrated to be applicable for the determination of nitrite in various pharmaceutical samples. The proposed UPLC-MS method was used to study the effect of nitrite content in pharmaceutical products on the formation of N-nitrosamines. The high importance of nitrites in relation to the N-nitrosation reaction was discussed. As deduced from theory and justified by the presented results, reducing the nitrite concentration could definitely solve the N-nitrosamine contamination. Nitrites, unlike secondary and tertiary amines, are universal precursors to any N-nitrosamine, so this solution is easily transferable to any relevant pharmaceutical product.
Nitrite-oxidizing bacteria (NOB) are ubiquitous and abundant microorganisms that play key roles in global nitrogen and carbon biogeochemical cycling. Despite recent advances in understanding NOB physiology and taxonomy, currently very few cultured NOB or representative NOB genome sequences from marine environments exist. In this study, we employed enrichment culturing and genomic approaches to shed light on the phylogeny and metabolic capacity of marine NOB. We successfully enriched two marine NOB (designated MSP and DJ) and obtained a high-quality metagenome-assembled genome (MAG) from each organism. The maximum nitrite oxidation rates of the MSP and DJ enrichment cultures were 13.8 and 30.0 μM nitrite per day, respectively, with these optimum rates occurring at 0.1 mM and 0.3 mM nitrite, respectively. Each enrichment culture exhibited a different tolerance to various nitrite and salt concentrations. Based on phylogenomic position and overall genome relatedness indices, both NOB MAGs were proposed as novel taxa within the Nitrospinota and Nitrospirota phyla. Functional predictions indicated that both NOB MAGs shared many highly conserved metabolic features with other NOB. Both NOB MAGs encoded proteins for hydrogen and organic compound metabolism and defense mechanisms for oxidative stress. Additionally, these organisms may have the genetic potential to produce cobalamin (an essential enzyme cofactor that is limiting in many environments) and, thus, may play an important role in recycling cobalamin in marine sediment. Overall, this study appreciably expands our understanding of the Nitrospinota and Nitrospirota phyla and suggests that these NOB play important biogeochemical roles in marine habitats.IMPORTANCE Nitrification is a key process in the biogeochemical and global nitrogen cycle. Nitrite-oxidizing bacteria (NOB) perform the second step of aerobic nitrification (converting nitrite to nitrate), which is critical for transferring nitrogen to other organisms for assimilation or energy. Despite their ecological importance, there are few cultured or genomic representatives from marine systems. Here, we obtained two NOB (designated MSP and DJ) enriched from marine sediments and estimated the physiological and genomic traits of these marine microbes. Both NOB enrichment cultures exhibit distinct responses to various nitrite and salt concentrations. Genomic analyses suggest that these NOB are metabolically flexible (similar to other previously described NOB) yet also have individual genomic differences that likely support distinct niche distribution. In conclusion, this study provides more insights into the ecological roles of NOB in marine environments.
- MeSH
- Bacteria klasifikace izolace a purifikace metabolismus MeSH
- dusitany metabolismus MeSH
- geologické sedimenty mikrobiologie MeSH
- metabolické sítě a dráhy MeSH
- mikrobiota * MeSH
- mořská voda mikrobiologie MeSH
- oxidace-redukce MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Korejská republika MeSH
Anaerobic ammonium-oxidizing (anammox) bacteria play an essential part in nitrogen removal in constructed wetlands. The objective of the present study was to explore the spatiotemporal dynamics of anammox bacterial communities and the associated factors in a full-scale constructed wetland for the treatment of polluted surface water. The abundance and diversity of anammox bacterial communities were characterized using quantitative polymerase chain reaction (PCR) and clone library analysis, respectively. Anammox bacterial diversity, richness, and abundance in the treatment wetland differed considerably among sampling sites and seasons, whereas anammox bacterial community structure tended to change slightly with site and time. Anammox abundance was likely influenced by temperature and the contents of nitrate and nitrite nitrogen. The increase of carbon and nitrogen contents could lower wetland anammox bacterial diversity and richness. Moreover, anammox bacterial diversity, richness, and abundance were also affected by wetland vegetation type. Candidatus Brocadia dominated in the treatment wetland, whereas Candidatus Kuenenia and a novel anammox phylotype were also detected. This work could provide some new insights towards anaerobic ammonium oxidization in surface water treatment wetland.
In Japan, adzuki bean is cooked with rice. During the cooking, the colour of rice becomes pale red. It is postulated that the red pigment is produced from procyanidins and that the ingestion of red rice causes the production of nitric oxide (•NO) in the stomach by reacting with salivary nitrite. The increase in colour intensity accompanied the decrease in the amounts of procyanidins, suggesting the conversion of procyanidins into the red pigment during the cooking. In addition, the red pigment combined with rice strongly. The red-coloured rice produced •NO by reacting with nitrite in artificial gastric juice, and the amounts were dependent on the contents of procyanidins and the equivalents. It is suggested that although adzuki procyanidins were oxidised during cooking with rice, procyanidins and the equivalents bound to rice still have the ability to produce bioactive •NO in the stomach using nitrite in mixed whole saliva.
- MeSH
- anthokyaniny metabolismus MeSH
- biflavonoidy metabolismus MeSH
- dusitany metabolismus MeSH
- katechin metabolismus MeSH
- kyselina askorbová metabolismus MeSH
- kyselina dehydroaskorbová metabolismus MeSH
- lidé MeSH
- oxid dusnatý metabolismus MeSH
- oxidace-redukce MeSH
- peptidylprolylisomerasa Pin1 MeSH
- proantokyanidiny metabolismus MeSH
- rýže (rod) metabolismus MeSH
- škrob MeSH
- sliny MeSH
- vaření * MeSH
- vigna chemie MeSH
- vysoká teplota MeSH
- žaludeční šťáva metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Japonsko MeSH
