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1.
Talanta ; 251: 123767, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35973252

RESUMO

The dynamic new psychoactive substances (NPS) market presents a great challenge for public health officers, law enforcement and analytical and forensic chemists. Wastewater analysis is a complementary tool in the ongoing surveillance of these compounds but the low doses, somewhat unknown metabolism and the different chemical classes have made analytical methods difficult to develop. The current study presents a direct injection method for the quantification of 32 NPS. These include a range of classes: phenethylamines (25C-NBOMe and 4-fluoroamphetamine), synthetic cathinones (3-methylmethcathinone, butylone, dibutylone, eutylone, methcathinone, N-ethylheptedrone, N-ethylhexedrone, N-ethylpentylone and pentylone), synthetic cannabinoid receptor agonists (5F-EMB-PICA, 5F-MDMB-PICA, 5F-MDMB-PINACA, AMB FUBINACA, MDMB-4en-PINACA, cumyl pegaclone and cumyl-5F-pegaclone), opioids (2-methyl AP-237, AP-238, brorphine, isotonitazene, metonitazene and protonitazene), benzodiazepines (clonazolam, etizolam, flualprazolam and flubromazolam), plant-based NPS (7-hydroxymitragynine and mitragynine) and dissociatives (2F-deschloroketamine, 2-oxo-PCE). The method was validated in terms of linearity, range, precision (interday and intraday), limit of detection and limit of quantification, while filtration losses and matrix effects were also examined. The method was applied to wastewater samples collected from New South Wales and Queensland over the 2021-22 New Year period, when recreational drug use was expected to increase. Three NPS were found: eutylone, clonazolam and etizolam, with eutylone having the highest mass loads.


Assuntos
Espectrometria de Massas em Tandem , Águas Residuárias , Analgésicos Opioides , Austrália , Benzodiazepinas , Agonistas de Receptores de Canabinoides , Canabinoides , Cromatografia Líquida/métodos , Imidazóis , Fenetilaminas , Piperidinas , Espectrometria de Massas em Tandem/métodos
2.
Protein Expr Purif ; 201: 106169, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36115639

RESUMO

ß-lactamases protect bacteria from ß-lactam antibiotics. Temoneira (TEM) is a class A serine ß-lactamase and its coding sequence is designed into DNA vectors, such as pET-21a (+), to provide antibiotic resistance. TEM-1 ß-lactamase was overexpressed efficiently from this vector upon inducing protein expression by IPTG in BL21(DE3) cells. Immobilized metal ion affinity chromatography (IMAC) was used based on the three native putative metal ion binding sites of TEM-1 ß-lactamase, each consisting of a pair of histidine sidechains. Elution was achieved at low concentrations of imidazole (∼15-200 mM). Two steps of IMAC and a subsequent anion exchange purification produced highly pure TEM-1 ß-lactamase with a yield of 1.9 mg/g of wet bacterial pellet weight. Mass spectrometry revealed that the mature form of ß-lactamase (without the signal sequence) was obtained. The secondary structure composition, calculated from the circular dichroism spectrum, showed that the target protein was folded similar to the published crystal structure. Ni(II) binding to the enzyme was also investigated. Increasing amounts of Ni(II) ions had only a small effect on the protein structure. Mass spectrometry detected up to three bound metal ions at 10:1 Ni(II):protein molar ratio, but the major peak was assigned to the monometallated ß-lactamase indicating the presence of a paramount metal ion binding site formed by the H151/H156 pair.


Assuntos
Metaloproteínas , beta-Lactamases , Antibacterianos , Sítios de Ligação , Cromatografia de Afinidade/métodos , Histidina , Imidazóis , Íons , Isopropiltiogalactosídeo , Metaloproteínas/metabolismo , Penicilinase/metabolismo , Sinais Direcionadores de Proteínas , Serina , beta-Lactamases/genética , beta-Lactamas/metabolismo
3.
J Colloid Interface Sci ; 630(Pt A): 666-675, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36274403

RESUMO

Rational synthesis of metal-organic frameworks (MOFs) via structural and morphology engineering are fundamental for enhanced heavy metal removal. Beyond tuning intrinsic characteristics, it is essential to address inseparability and instability issues of MOFs to fulfill the practical applications. Herein, we successfully constructed macroscopic zeolitic imidazole frameworks-functionalized melamine sponge (MS@ZIFx, x represents the ultrasonication duration) using a facile dip-coating method. By varying ultrasonication duration, the morphology and structure of the loaded ZIF were modulated from leaf-shaped phase to hollow mixed phase to achieve the excellent adsorption performance. The optimized MS-ZIF10 exhibited significantly enhanced performance for Pb(II) and Cu(II) adsorption. Specifically, the MS-ZIF10 combined high adsorption capacities (624.8 and 588.6 mg g-1 for Pb(II) and Cu(II), respectively), rapid kinetics, excellent anti-interfering capability (e.g., cations, dissolved organic matters) with outstanding reusability (removal efficiency > 91.8 % after 10 cycles). The MS-ZIF10 presented satisfactory performance on Pb(II) and Cu(II) removal in various real water matrices. Fixed-bed experiments were performed to assess the practicality of MS-ZIF10, and 1821 bed volumes (BVs) and 1630 BVs of feeding streams containing Pb(II) and Cu(II) were effectively treated. This work proposed a novel paradigm for promoting the MOF's performance and simultaneously boosting MOF's application in actual heavy metal removal.


Assuntos
Estruturas Metalorgânicas , Metais Pesados , Poluentes Químicos da Água , Zeolitas , Chumbo , Poluentes Químicos da Água/química , Metais Pesados/química , Adsorção , Estruturas Metalorgânicas/química , Imidazóis , Cinética
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121867, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36108408

RESUMO

Fluorescent material exhibiting aggregation-induced emission (AIE) has demonstrated to be a facile and effective method to detect 2,4,6-trinitrophenol (TNP) due to its excellent features. In this study, a novel diphenyl imidazole-based fluorescent material (DINP) was successfully synthesized via a facile method. Fluorescence spectra showed that DINP had a typical AIE effect in DMSO/water solution, and the fluorescence emission was effectively quenched by TNP without being affected by other explosives. The Stern-Volmer quenching constant of 2.70 × 105 M-1 and detection limit of 7.2 × 10-8 M demonstrated that the DINP aggregates could serve as potential chemosensor for TNP detection. The mechanism behind the quenching of fluorescence could be ascribed to the formation of ground state complex. In addition, fluorescent test strips and TLC plate prepared with the aggregates provided an easy and low cost method for TNP detection in the aqueous solution. Especially, DINP was applied to quantitatively detect the content of TNP in real water samples. Furthermore, the aggregates exhibited good selective adsorptive performance to rhodamine B dye in aqueous solution with high adsorption efficiency of 98 % in a few minutes.


Assuntos
Corantes Fluorescentes , Água , Espectrometria de Fluorescência/métodos , Imidazóis
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 286: 121948, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36252301

RESUMO

Crystal polymorphs of fluorinated ionic liquids (fILs) were examined at low-temperature (LT) by Raman spectroscopy. The fILs were 1-alkyl-3-methylimidazolium perfluorobutanesulfonate, [Cnmim][PFBS] (n = 4, 6, and 8). The cations and anion possess conformational degrees of freedom. Various LT phases were derived from the conformational polymorphs of the cations and the anion. Conformational flexibility depended on alkyl chain length. The crystal polymorphs in the fILs were sensitive to molecular conformations and flexibility.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Imidazóis/química , Conformação Molecular , Cátions/química , Ânions
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 286: 121971, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36288627

RESUMO

Novel conjugates consist of 4-styrylpyridinium dye and 2,2-diphenyl-2H-chromene moiety were obtained, and their affinity to double stranded DNA and cucurbit[7]uril was investigated. With a combination of absorption, fluorescence and circular dichroism spectroscopies as well as MALDI-TOF mass spectrometry, we demonstrate that these compounds can interact with macromolecules to form of the supramolecular assemblies due to two suitable binding sites. The ternary complex is formed as a result of the intercalation of a positively charged styryl part between DNA base pairs, while cucurbit[7]uril is located on the alkyl chain between two moieties of conjugate. All these findings provide valuable information into controlling the interaction between organic molecules, DNA and cucurbit[7]uril.


Assuntos
Hidrocarbonetos Aromáticos com Pontes , Imidazóis , Hidrocarbonetos Aromáticos com Pontes/química , Imidazóis/química , DNA , Benzopiranos
7.
Talanta ; 252: 123903, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36084572

RESUMO

Accurate differentiation of tumor cells from normal cells is a fundamental and critical challenge for the early diagnosis of cancer. The intrinsic low-polarity and increased numbers of lipid droplets can be utilized as potential biomarkers for tumor cells. Therefore, we synthesized and screened the polar fluorescent probe (PI-CHO), which exhibiting notable fluorescence color change and spectral shift in solvents of different polarities. PI-CHO has a high sensitivity to polarity changes in the linear range of ET(30) = 37.4-63.1, with a fluorescence enhancement of more than 474-folds. Intracellular imaging experiments showed that PI-CHO has low cytotoxicity, excellent lipid droplet-targeted performance and discernibility between tumor and normal cells. Ex vivo imaging of the tumors and major organs demonstrated the great reliability and sensitive responsiveness of PI-CHO towards tumors. Moreover, the proposed probe was successfully applied to detect tumors in living mice, exhibiting the potential to become a powerful tool in early cancer diagnosis.


Assuntos
Gotículas Lipídicas , Neoplasias , Camundongos , Animais , Reprodutibilidade dos Testes , Corantes Fluorescentes , Neoplasias/diagnóstico por imagem , Imidazóis , Imagem Óptica/métodos
8.
Ann Pharmacother ; 57(1): 99-106, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35502451

RESUMO

OBJECTIVE: To review the pharmacology, efficacy, and safety of ibrexafungerp in the management of vulvovaginal candidiasis (VVC). DATA SOURCES: Literature was sought using PubMed (1966-February 2022) and EMBASE (1973-February 2022), and clinicaltrials.gov. Search terms included ibrexafungerp, SCY-078, and VVC. STUDY SELECTION AND DATA EXTRACTION: All studies including humans and published in English with data assessing the efficacy and safety of ibrexafungerp for the treatment of VVC were evaluated. DATA SYNTHESIS: A phase 2 dose-finding study found ibrexafungerp had similar efficacy to fluconazole in the clinical cure of VVC (51.9% vs 58.3%, respectively). Two phase 3 clinical trials demonstrated ibrexafungerp had statistical superiority over placebo for clinical cure in moderate to severe VVC (P < 0.001 and P = 0.023, respectively). The most frequently reported adverse reactions in the clinical trials were gastrointestinal-related symptoms. To date, data comparing efficacy of ibrexafungerp and topical imidazoles in the treatment of VVC are nonexistent. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: Topical imidazoles and oral fluconazole are effective for the treatment of uncomplicated VVC. Due to increased resistance, limited fluconazole coverage for non-Candida albicans species, and potential for significant drug interactions associated with fluconazole use, alternative treatments for VVC are needed. Ibrexafungerp is a new oral triterpenoid antifungal agent indicated for the treatment of VVC. Additional clinical trials are needed to evaluate long-term safety data as well as efficacy and safety in specialty populations. CONCLUSION: Ibrexafungerp, a recently approved triterpenoid antifungal agent, is an effective and well-tolerated option for the treatment of VVC.


Assuntos
Candidíase Vulvovaginal , Triterpenos , Feminino , Humanos , Candidíase Vulvovaginal/tratamento farmacológico , Fluconazol/efeitos adversos , Antifúngicos/efeitos adversos , Triterpenos/uso terapêutico , Imidazóis/uso terapêutico
9.
Protein Expr Purif ; 201: 106186, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36206960

RESUMO

Human fibroblast growth factor 19 (hFGF19) belongs to the endocrine FGF19 superfamily and is considered a potential agent to treat severe or relapsing nonalcoholic fatty liver disease. Numerous studies have confirmed the beneficial effects of this hormone on the related symptoms of the disease and attempts at producing recombinant proteins in various hosts are steadily proliferating. Recently, we reported that authentic hFGF19 can be solubly expressed through combining synonymous codon substitutions and co-expression with disulfide-bond isomerase (DsbC) in Escherichia coli. However, during purification, hFGF19 without the His-tag occasionally co-eluted with His-tagged DsbC when using metal affinity chromatography, thereby requiring auxiliary purification steps to achieve apparent homogeneity. This phenomenon provides evidence that hFGF19 specifically interacts with immobilized Ni2+, which can thus be used as an alternative tool for the purification of hFGF19. Consequently, we could simply and reproducibly purify hFGF19 from cell lysates by using Ni2+-immobilized metal affinity chromatography and stepwise gradient elution with imidazole.


Assuntos
Escherichia coli , Metais , Cromatografia de Afinidade/métodos , Dissulfetos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Hormônios/metabolismo , Humanos , Imidazóis/metabolismo , Isomerases , Metais/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
10.
Cell Death Differ ; 29(1): 230-245, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34453119

RESUMO

Mounting evidence indicates that immunogenic therapies engaging the unfolded protein response (UPR) following endoplasmic reticulum (ER) stress favor proficient cancer cell-immune interactions, by stimulating the release of immunomodulatory/proinflammatory factors by stressed or dying cancer cells. UPR-driven transcription of proinflammatory cytokines/chemokines exert beneficial or detrimental effects on tumor growth and antitumor immunity, but the cell-autonomous machinery governing the cancer cell inflammatory output in response to immunogenic therapies remains poorly defined. Here, we profiled the transcriptome of cancer cells responding to immunogenic or weakly immunogenic treatments. Bioinformatics-driven pathway analysis indicated that immunogenic treatments instigated a NF-κB/AP-1-inflammatory stress response, which dissociated from both cell death and UPR. This stress-induced inflammation was specifically abolished by the IRE1α-kinase inhibitor KIRA6. Supernatants from immunogenic chemotherapy and KIRA6 co-treated cancer cells were deprived of proinflammatory/chemoattractant factors and failed to mobilize neutrophils and induce dendritic cell maturation. Furthermore, KIRA6 significantly reduced the in vivo vaccination potential of dying cancer cells responding to immunogenic chemotherapy. Mechanistically, we found that the anti-inflammatory effect of KIRA6 was still effective in IRE1α-deficient cells, indicating a hitherto unknown off-target effector of this IRE1α-kinase inhibitor. Generation of a KIRA6-clickable photoaffinity probe, mass spectrometry, and co-immunoprecipitation analysis identified cytosolic HSP60 as a KIRA6 off-target in the IKK-driven NF-κB pathway. In sum, our study unravels that HSP60 is a KIRA6-inhibitable upstream regulator of the NF-κB/AP-1-inflammatory stress responses evoked by immunogenic treatments. It also urges caution when interpreting the anti-inflammatory action of IRE1α chemical inhibitors.


Assuntos
Endorribonucleases , Retículo Endoplasmático/metabolismo , Endorribonucleases/metabolismo , Humanos , Imidazóis , Morte Celular Imunogênica , Inflamação/metabolismo , Naftalenos , Pirazinas
11.
Biosensors (Basel) ; 12(11)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36354439

RESUMO

Nanozymes are highly desired to overcome the shortcomings of natural enzymes, such as low stability, high cost and difficult storage during biosensing applications. Herein, by imitating the structure of natural enzymes, we propose a one-pot annealing process to synthesis imidazole-ring-modified graphitic carbon nitride (g-C3N4-Im) with enhanced peroxidase-like activity. g-C3N4-Im shows enhanced peroxidase-like activity by 46.5 times compared to unmodified g-C3N4. Furthermore, imidazole rings of g-C3N4-Im make it possible to anchor Cu(II) active sites on it to produce g-C3N4-Im-Cu, which shows a further increase in peroxidase-like activity by three times. It should be noted that the as-prepared g-C3N4-Im-Cu could show obvious peroxidase-like activity over a broad range of pH values and at a low temperature (5 °C). The ultrahigh peroxidase-like activity is attributed to the electronic effect of imidazole rings and the active sites of Cu(II) for ·OH production. Based on the enhanced peroxidase-like activity, a H2O2 and glucose biosensor was developed with a high sensitivity (limit of detection, 10 nM) and selectivity. Therefore, the biosensor shows potential for applications in diabetic diagnoses in clinical practice.


Assuntos
Colorimetria , Peróxido de Hidrogênio , Peroxidase , Peroxidases/química , Glucose , Imidazóis
12.
Dalton Trans ; 51(45): 17263-17276, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36317406

RESUMO

In recent years, Ru(II) complexes have gained high importance in medicinal chemistry due to their significant anti-cancer activities, which are directly related to their DNA binding ability. In this report, the chemistry and cytotoxicity of two new Ru(II) complexes containing imidazole pyridine (Ru-1) and imidazole quinoline (Ru-2) have been studied. The prepared compounds were characterized using infrared (IR), nuclear magnetic resonance (NMR), mass spectrometry (MS), isothermal titration calorimetry (ITC), UV-Vis, and fluorescence spectral techniques. The structural analyses show that the Ru(II) complexes exhibit a 'piano stool' coordination geometry and they are composed of one bound arene, two sigma bonded benzil nitrogen atoms, and labile chlorine linked to Ru(II). The photo-physical properties of these complexes were examined, and they exhibit absorption peaks at 260 nm and 380 nm, which are due to the involvement of intra-ligand charge transitions (ILCT) and metal-to-ligand charge transitions (MLCT), respectively. The binding process of the Ru(II) complexes with DNA and BSA is non-covalent in nature and the binding constants of Ru-1 and Ru-2 complexes with DNA and BSA were found to be 1 × 105 M-1 and 1 × 103 M-1, respectively. In the presence of the Ru(II) complexes, ethidium bromide (EtBr) is competitively displaced from DNA by intercalation of the Ru(II) complexes in DNA and it is well corroborated by viscosity and in silico studies. Both the ligands and Ru(II) complexes were carefully investigated in vitro for cytotoxicity against HeLa, MCF-7, and MDA-MB-231 cells. Surprisingly, both Ru(II) complexes exhibit superior cytotoxicity to cisplatin with a low LD50 value against the examined cancer cells. Besides, an insignificant effect on HEK normal cells (LD50 > 140 µM) was observed.


Assuntos
Antineoplásicos , Complexos de Coordenação , Quinolinas , Rutênio , Humanos , Rutênio/química , Ligantes , Complexos de Coordenação/química , Estrutura Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , DNA/química , Imidazóis/farmacologia , Quinolinas/farmacologia , Piridinas/farmacologia , Linhagem Celular Tumoral
13.
Langmuir ; 38(46): 14326-14334, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36355865

RESUMO

Combination chemotherapy is recognized as a vital medical treatment for cancer, but it has not achieved clinical ideal effects of combination therapy. Herein, we designed a supramolecular combination chemotherapy strategy based on cucurbit[8]uril (CB[8]), which can be facilely assembled into dual platinum drugs. Interestingly, employing the CB[8] carrier led to a greater than 10-fold intracellular Pt content compared to that of dual drugs at 4 h, and the CB[8] complex (CLE) can enhance the infiltration of platinum drugs in colorectal tumor cells tremendously. The platinum drugs can be released from CLE through consuming more tumor biomarker spermidine. Through analyzing the nanomechanical property of the colorectal tumor cellular surface by bioscope AFM, it was revealed that CLE modified the property by decreasing the adhesion and increasing the stiffness. This study provided a facile and sensitive strategy for improving combination chemotherapy by supramolecular materials.


Assuntos
Neoplasias Colorretais , Platina , Humanos , Hidrocarbonetos Aromáticos com Pontes , Imidazóis , Neoplasias Colorretais/tratamento farmacológico
14.
Sci Rep ; 12(1): 19942, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36402805

RESUMO

Cr2O3 nanoparticles were prepared using Zingiber officinal extract which were used as an efficient and reusable catalyst in the practical synthesis of polysubstituted imidazoles by means of a convenient reaction of aromatic aldehydes with ammonium acetate and benzil under microwave irradiation and H2O as solvent. The structure of the compounds was studied by IR and 1H-NMR spectrum. The most important benefits of this process are operational simplicity, reasonable reaction times, and excellent yield of products. The results show that the optimal conditions for the formation of imidazole derivatives are as follow: power of 400 W, reaction time of 4-9 min, H2O as a solvent, and 15 mmol of catalyst amount.


Assuntos
Micro-Ondas , Nanopartículas , Nanopartículas/química , Imidazóis/química , Solventes , Extratos Vegetais
15.
Steroids ; 188: 109135, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36336105

RESUMO

Synthesis of 21,22-cyclosteroids has been achieved starting from pregnenolone acetate. The key transformation was the Kulinkovich reaction of 17-vinyl steroids with esters. The resulting cyclopropanols were further subjected to three-membered ring-opening under various conditions including to base-, palladium or visible light-promoted isomerization and cross-coupling reaction. A number of steroidal Δ2-6-ketones and 3ß-hydroxy-Δ5-enes with functional groups at C-21 - C-23 have been synthesized via the 21,22-cyclosteroids. The antiproliferative and antihormonal activity of the obtained compounds on the cell lines of prostate (22Rv1) and breast (MCF-7) cancer was studied. The androgen receptor activity was assessed by reporter assay when the expression of signalling proteins was evaluated by immunoblotting. (20S,22R)-22-Acetoxy-21,22-cyclo-5α-cholest-5-ene with the moderate antiandrogenic potency revealed IC50 values of 18.4 ± 1.2 and 14.6 ± 1.4 µM against MCF-7 and 22Rv1 cells, respectively, and its effects on the expression of AR-V7, cyclin D1 and BCL2 were explored.


Assuntos
Antineoplásicos , Ciclosteroides , Humanos , Masculino , Linhagem Celular Tumoral , Proliferação de Células , Ciclosteroides/química , Ciclosteroides/farmacologia , Imidazóis , Pregnenolona , Receptores Androgênicos/metabolismo , Esteroides , Neoplasias da Mama/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/farmacologia
16.
Molecules ; 27(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36431821

RESUMO

An electrochemically induced synthesis of imidazoles from vinyl azides and benzyl amines was developed. A wide range of imidazoles were obtained, with yields of 30 to 64%. The discovered transformation is a multistep process whose main steps include the generation of electrophilic iodine species, 2H-azirine formation from the vinyl azide, followed by its reactions with benzyl amine and with imine generated from benzyl amine. The cyclization and aromatization of the obtained intermediate lead to the target imidazole. The synthesis proceeds under constant current conditions in an undivided cell. Despite possible cathodic reduction of various unsaturated intermediates with C=N bonds, the efficient electrochemically induced synthesis of imidazoles was carried out.


Assuntos
Aminas , Azidas , Azidas/química , Catálise , Imidazóis/química , Ciclização
17.
Molecules ; 27(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36364372

RESUMO

The 2-imidazoline nitroxide derivatives of cymantrene-2-(η5-cyclopentadienyl)tricarbonylmanganese(I)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (NNMn) and 2-(η5-cyclopentadienyl)tricarbonylmanganese(I)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-1-oxyl (INMn) were synthesized. It was shown that NNMn and INMn exhibit a sufficiently high kinetic stability both in solids and in solutions under normal conditions. Their structural characteristics, magnetic properties and electrochemical behavior are close to Re(I) analogs. This opens the prospect of using paramagnetic cymantrenes as prototypes in the design of Re(I) half-sandwiched derivatives for theranostics, where therapy is combined with diagnostics by magnetic resonance imaging due to the contrast properties of nitroxide radicals.


Assuntos
Imidazóis , Óxidos de Nitrogênio , Óxidos de Nitrogênio/química , Imidazóis/química
18.
Molecules ; 27(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36364434

RESUMO

The whitefly, Bemisia tabaci, is the main pest for many field and horticultural crops, causing main and significant problems. The efficiency of imidacloprid insecticide as seed treatment and foliar spray at three rates against the whitefly, B. tabaci, was evaluated in tomato plants under field conditions; in addition, insecticide residues were determined in tomato leaves and fruits. The obtained results revealed that the seedlings produced from treated seeds with imidacloprid were the most effective treatment in decreasing whitefly stages. Reduction percentages of whitefly stages in seedlings produced from treated seeds and sprayed with ½, ¾ and 1 field rates of imidacloprid were more than that produced from untreated seeds. Tomato fruit yield in seedlings produced from treated seeds and sprayed with one recommended rate of imidacloprid was more than that of untreated seeds. The residues of imidacloprid in leaves and fruits in seedlings produced from treated seeds and sprayed with field rate were more than that of untreated seeds; additionally, the residues were higher in leaves than in fruits. The residual level in fruits was less than the maximum residual level (MRL = 1 mg kg-1) of the Codex Alimentarius Commission. The half-life (t ½) was 6.99 and 6.48 days for leaves and fruits of seedlings produced from treated seeds and 5.59 and 4.59 days for untreated seeds. Residues in tomato fruits were less than the MRL, therefore, imidacloprid is considered an unconventional insecticide appropriate for B. tabaci control that could be safe for the environment.


Assuntos
Hemípteros , Inseticidas , Lycopersicon esculentum , Animais , Inseticidas/farmacologia , Imidazóis/farmacologia , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Plântula
19.
Water Res ; 226: 119316, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36369691

RESUMO

As a class of emerging aquatic pollutants, alkylimidazole-based ionic liquids (AM-ILs) have received extensive attention due to the large acute toxicity to aquatic organisms. Therefore, in order to protect both aquatic organisms and human beings, it is necessary to seek an efficient and environmental-friendly technology for removal of AM-ILs from water bodies. In this work, we found that under simulated sunlight (Xe lamp) irradiation, periodate (KIO4, PI) could efficiently degrade 1-hexyl-2,3-dimethylimidazolium bromide ([HMMIm]Br), a representative AM-ILs with six carbon atoms in the side chain. Kinetics experiments on the degradation of [HMMIm]Br were performed, and the results showed that a high degradation efficiency (≥90.00%) of the cation ([HMMIm]+) was still maintained under harsh water conditions of strong acidity/alkaliny or with various non-target inorganic ions. More importantly, the anion of bromide ion (Br-) was not oxidized to the carcinogenic bromate (BrO3-) in current reaction system. The excited stated PI (marked as PI*) was detected by Laser flash photolysis, and it was an important reactive species for [HMMIm]+ degradation. As rationalized by theoretical calculations and scavenging experiments, the main oxidation mechanisms of [HMMIm]+ were hydroxyl radicals induced substitution reaction, PI* initiated electron and double oxygen transfer, and direct photolysis mediated chemical bond cleavage reaction, which contributed to 73%, 21%, and 6% of [HMMIm]+ degradation, respectively. Moreover, toxicity evaluation by ECOSAR software indicated that the oxidation products were generally less toxic to three aquatic organisms (fish, water flea, and green algae) than the target molecule [HMMIm]Br. In conclusion, this work proposed novel oxidation mechanisms of sunlight-activated PI system, and the findings may inspire further researches on the application of photoactivated hypervalent acids in water purification.


Assuntos
Líquidos Iônicos , Poluentes Químicos da Água , Animais , Humanos , Líquidos Iônicos/química , Luz Solar , Brometos , Poluentes Químicos da Água/química , Fotólise , Cinética , Imidazóis/química
20.
Georgian Med News ; (330): 6-10, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36427832

RESUMO

Objective - to determine the sensitivity of Gardnerella vaginalis to fenticonazole to justify the feasibility of using this mainly antifungal drug for local treatment of BV in cases when it is a multifactorial disease caused by Gardnerella vaginalis and Candida spp. simultaneously.; We observed 98 women with infections of the urogenital tract at the ages of 20 to 49. At the first stage of the study, we analyzed the results of laboratory data on pathological discharge from the urogenital system of these patients. 36 (%) of the examined women had Gardnerella vaginalis in the vaginal discharge. At the second stage of the study, the sensitivity of Gardnerella vaginalis to fenticonazole was determined.; The resistance to fenticonazole was registered in 1 case (2.7%). In the remaining 35 patients Gardnerella vaginalis was not stable to fenticonazole. High sensitivity to this substance was found in 22 of them (61.2%). Respectively, low sensitivity was registered in 13 people from the observation group (36.1%).; Gardnerella vaginalis is the main constituent and a marker of bacterial vaginosis. The elimination of this very microorganism is of paramount importance for its treatment. In 35 studied patients (97.3%) Gardnerella vaginalis, which was isolated by culture from vaginal discharge, had sensitivity to fenticonazole. Moreover, in 22 of them (61.2%) the sensitivity was high, and low in 13 (36.1%). Candida spp. was found in 17 (47.1%) of 36 patients with bacterial vaginosis. It is appropriate to use fenticonazole as a means of local treatment during complex therapy of women with bacterial vaginosis that improves its compliance.


Assuntos
Descarga Vaginal , Vaginose Bacteriana , Humanos , Feminino , Gardnerella vaginalis , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/microbiologia , Imidazóis , Candida
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