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1.
Lancet Haematol ; 11(7): e487-e498, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38824932

RESUMO

BACKGROUND: Iadademstat is a potent, selective, oral inhibitor of both the enzymatic and scaffolding activities of the transcriptional repressor lysine-specific demethylase 1 (LSD1; also known as KDM1A) that showed promising early activity and safety in a phase 1 trial and strong preclinical synergy with azacitidine in acute myeloid leukaemia cell lines. Therefore, we aimed to investigate the combination of iadademstat and azacitidine for the treatment of adult patients with newly diagnosed acute myeloid leukaemia. METHODS: The open-label, phase 2a, dose-finding ALICE study was conducted at six hospitals in Spain and enrolled patients aged 18 years or older with newly diagnosed acute myeloid leukaemia not eligible for intensive chemotherapy and an ECOG performance status of 0-2. In the dose escalation portion of the trial, patients received a starting dose of iadademstat at 90 µg/m2 per day (with de-escalation to 60 µg/m2 per day and escalation up to 140 µg/m2 per day) orally, for 5 days on, 2 days off weekly, with azacitidine 75 mg/m2 subcutaneously, for seven of 28 days. The primary objectives were safety (analysed in the safety analysis set; all patients who received at least one dose of study treatment) and establishing the recommended phase 2 dose; secondary objectives included response rates in the efficacy analysis set (all patients who had at least one efficacy assessment). This study is registered on EudraCT (EudraCT 2018-000482-36) and has been completed. FINDINGS: Between Nov 12, 2018, and Sept 30, 2021, 36 patients with newly diagnosed acute myeloid leukaemia were enrolled; the median age was 76 (IQR 74-79) years, all patients were White, 18 (50%) were male, and 18 (50%) were female, and all had intermediate-risk or adverse-risk acute myeloid leukaemia. The median follow-up was 22 (IQR 16-31) months. The most frequent (≥10%) adverse events considered to be related to treatment were decreases in platelet (25 [69%]) and neutrophil (22 [61%]) counts (all grade 3-4) and anaemia (15 [42%]; of which ten [28%] were grade 3-4). Three patients had treatment-related serious adverse events (one fatal grade 5 intracranial haemorrhage, one grade 3 differentiation syndrome, and one grade 3 febrile neutropenia). Based on safety, pharmacokinetic and pharmacodynamic data, and efficacy, the recommended phase 2 dose of iadademstat was 90 µg/m2 per day with azacitidine. 22 (82%; 95% CI 62-94) of 27 patients in the efficacy analysis set had an objective response. 14 (52%) of 27 patients had complete remission or complete remission with incomplete haematological recovery; of these, ten of 11 evaluable for measurable residual disease achieved negativity. In the safety analysis set, 22 (61%) of 36 patients had an objective response. INTERPRETATION: The combination of iadademstat and azacitidine has a manageable safety profile and shows promising responses in patients with newly diagnosed acute myeloid leukaemia, including those with high-risk prognostic factors. FUNDING: Oryzon Genomics and Spain's Ministerio de Ciencia, Innovacion y Universidades (MICIU)-Agencia Estatal de Investigacion (AEI).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Azacitidina , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Azacitidina/uso terapêutico , Azacitidina/administração & dosagem , Azacitidina/efeitos adversos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Histona Desmetilases/antagonistas & inibidores , Adulto , Relação Dose-Resposta a Droga , Idoso de 80 Anos ou mais , Cicloexanos , Diaminas
2.
Environ Sci Pollut Res Int ; 31(30): 42889-42901, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38884933

RESUMO

Naphthenic acids (NA) are organic compounds commonly found in crude oil and produced water, known for their recalcitrance and toxicity. This study introduces a new adsorbent, a polymer derived from spent coffee grounds (SCGs), through a straightforward cross-linking method for removing cyclohexane carboxylic acid as representative NA. The adsorption kinetics followed a pseudo-second-order model for the data (0.007 g min-1 mg-1), while the equilibrium data fitted the Sips model ( q m = 140.55 mg g-1). The process's thermodynamics indicated that the target NA's adsorption was spontaneous and exothermic. The localized sterical and energetic aspects were investigated through statistical physical modeling, which corroborated that the adsorption occurred indeed in monolayer, as suggested by the Sips model, but revealed the contribution of two energies per site ( n 1 ; n 2 ). The number of molecules adsorbed per site ( n ) was highly influenced by the temperature as n 1 decreased with increasing temperature and n 2 increased. These results were experimentally demonstrated within the pH range between 4 and 6, where both C6H11COO-(aq.) and C6H11COOH(aq.) species coexisted and were adsorbed by different energy sites. The polymer produced was naturally porous and amorphous, with a low surface area of 20 to 30 m2 g-1 that presented more energetically accessible sites than other adsorbents with much higher surface areas. Thus, this study shows that the relation between surface area and high adsorption efficiency depends on the compatibility between the energetic states of the receptor sites, the speciation of the adsorbate molecules, and the temperature range studied.


Assuntos
Ácidos Carboxílicos , Café , Polímeros , Adsorção , Café/química , Ácidos Carboxílicos/química , Polímeros/química , Cinética , Cicloexanos/química , Poluentes Químicos da Água/química , Termodinâmica
3.
Sci Rep ; 14(1): 13980, 2024 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886484

RESUMO

Maraviroc (MVC) is an antiretroviral drug capable of binding to CCR5 receptors and block HIV entry into target cells. Moreover, MVC can activate NF-kB pathway and induce viral transcription in HIV-infected cells, being proposed as a latency reversal agent (LRA) in HIV cure strategies. However, the evaluation of immunological and metabolic parameters induced by MVC concentrations capable of inducing HIV transcription have not been explored in depth. We cultured isolated CD4 T cells in the absence or presence of MVC, and evaluated the frequency of CD4 T cell subpopulations and activation markers levels by flow cytometry, and the oxidative and glycolytic metabolic rates of CD4 T cells using a Seahorse Analyzer. Our results indicate that a high concentration of MVC did not increase the levels of activation markers, as well as glycolytic or oxidative metabolic rates in CD4 T cells. Furthermore, MVC did not induce significant changes in the frequency and activation levels of memory cell subpopulations. Our data support a safety profile of MVC as a promising LRA candidate since it does not induce alterations of the immunological and metabolic parameters that could affect the functionality of these immune cells.


Assuntos
Linfócitos T CD4-Positivos , Maraviroc , Maraviroc/farmacologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Humanos , Glicólise/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Infecções por HIV/imunologia , Células Cultivadas , Triazóis/farmacologia , HIV-1/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Antagonistas dos Receptores CCR5/farmacologia , Cicloexanos/farmacologia , Adulto
4.
Microbiol Spectr ; 12(7): e0389523, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38809042

RESUMO

The susceptibility of genetically divergent HIV-1 strains (HIV-1 non-M) from groups O, N, and P to the CCR5 co-receptor antagonist, maraviroc (MVC), was investigated among a large panel of 45 clinical strains, representative of the viral genetic diversity. The results were compared to the reference strains of HIV-1 group M (HIV-1/M) with known tropism. Among the non-M strains, a wide range of phenotypic susceptibilities to MVC were observed. The large majority of HIV-1/O strains (40/42) displayed a high susceptibility to MVC, with median and mean IC50 values of 1.23 and 1.33 nM, respectively, similar to the HIV-1/M R5 strain (1.89 nM). However, the two remaining HIV-1/O strains exhibited a lower susceptibility (IC50 at 482 and 496 nM), in accordance with their dual/mixed (DM) tropism. Interestingly, the two HIV-1/N strains demonstrated varying susceptibility patterns, despite always having relatively low IC50 values (2.87 and 47.5 nM). This emphasized the complexity of determining susceptibility solely based on IC50 values. Our study examined the susceptibility of all HIV-1 non-M groups to MVC and correlated these findings with virus tropism (X4, R5, or DM). The results confirm the critical significance of tropism determination before initiating MVC treatment in patients infected with HIV-1 non-M. Furthermore, we advocate for the consideration of additional parameters, such as the slope of inhibition curves, to provide a more thorough characterization of phenotypic susceptibility profiles. IMPORTANCE: Unlike HIV-1 group M, the scarcity of studies on HIV-1 non-M groups (O, N, and P) presents challenges in understanding their susceptibility to antiretroviral treatments, particularly due to their natural resistance to non-nucleoside reverse transcriptase inhibitors. The TROPI-CO study logically complements our prior investigations into integrase inhibitors and anti-gp120 efficacy. The largest panel of 45 non-M strains existing so far yielded valuable results on maraviroc (MVC) susceptibility. The significant variations in MVC IC50 reveal a spectrum of susceptibilities, with most strains displaying R5 tropism. Notably, the absence of MVC-resistant strains suggests a potential therapeutic avenue. The study also employs a robust novel cell-based phenotropism assay and identifies distinct groups of susceptibilities based on inhibition curve slopes. Our findings emphasize the importance of determining tropism before initiating MVC and provide crucial insights for selecting effective therapeutic strategies in the delicate context of HIV-1 non-M infections.


Assuntos
Antagonistas dos Receptores CCR5 , Infecções por HIV , HIV-1 , Maraviroc , Tropismo Viral , HIV-1/efeitos dos fármacos , HIV-1/genética , HIV-1/fisiologia , Maraviroc/farmacologia , Humanos , Antagonistas dos Receptores CCR5/farmacologia , Infecções por HIV/virologia , Infecções por HIV/tratamento farmacológico , Concentração Inibidora 50 , Triazóis/farmacologia , Fenótipo , Testes de Sensibilidade Microbiana , Receptores CCR5/metabolismo , Receptores CCR5/genética , Fármacos Anti-HIV/farmacologia , Cicloexanos/farmacologia , Farmacorresistência Viral/genética , Inibidores da Fusão de HIV/farmacologia
5.
Front Cell Infect Microbiol ; 14: 1323157, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38808063

RESUMO

The genus Serratia harbors opportunistic pathogenic species, among which Serratia marcescens is pathogenic for honeybees although little studied. Recently, virulent strains of S. marcescens colonizing the Varroa destructor mite's mouth were found vectored into the honeybee body, leading to septicemia and death. Serratia also occurs as an opportunistic pathogen in the honeybee's gut with a low absolute abundance. The Serratia population seems controlled by the host immune system, but its presence may represent a hidden threat, ready to arise when honeybees are weakened by biotic and abiotic stressors. To shed light on the Serratia pathogen, this research aims at studying Serratia's development dynamics in the honeybee body and its interactions with the co-occurring fungal pathogen Vairimorpha ceranae. Firstly, the degree of pathogenicity and the ability to permeate the gut epithelial barrier of three Serratia strains, isolated from honeybees and belonging to different species (S. marcescens, Serratia liquefaciens, and Serratia nematodiphila), were assessed by artificial inoculation of newborn honeybees with different Serratia doses (104, 106, and 108 cells/mL). The absolute abundance of Serratia in the gut and in the hemocoel was assessed in qPCR with primers targeting the luxS gene. Moreover, the absolute abundance of Serratia was assessed in the gut of honeybees infected with V. ceranae at different development stages and supplied with beneficial microorganisms and fumagillin. Our results showed that all tested Serratia strains could pass through the gut epithelial barrier and proliferate in the hemocoel, with S. marcescens being the most pathogenic. Moreover, under cage conditions, Serratia better proliferates when a V. ceranae infection is co-occurring, with a positive and significant correlation. Finally, fumagillin and some of the tested beneficial microorganisms could control both Serratia and Vairimorpha development. Our findings suggest a correlation between the two pathogens under laboratory conditions, a co-occurring infection that should be taken into consideration by researches when testing antimicrobial compounds active against V. ceranae, and the related honeybees survival rate. Moreover, our findings suggest a positive control of Serratia by the environmental microorganism Apilactobacillus kunkeei in a in vivo model, confirming the potential of this specie as beneficial bacteria for honeybees.


Assuntos
Nosema , Serratia , Animais , Abelhas/microbiologia , Serratia/patogenicidade , Serratia/genética , Serratia/crescimento & desenvolvimento , Nosema/patogenicidade , Nosema/crescimento & desenvolvimento , Nosema/fisiologia , Nosema/genética , Serratia marcescens/patogenicidade , Serratia marcescens/crescimento & desenvolvimento , Serratia marcescens/genética , Trato Gastrointestinal/microbiologia , Infecções por Serratia/microbiologia , Cicloexanos/farmacologia , Serratia liquefaciens/crescimento & desenvolvimento , Serratia liquefaciens/genética , Ácidos Graxos Insaturados , Sesquiterpenos
6.
J Chromatogr A ; 1721: 464850, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38564932

RESUMO

The solvation parameter model uses five system independent descriptors to characterize compound properties defined as excess molar refraction, E, dipolarity/polarizability, S, hydrogen-bond acidity, A, hydrogen-bond basicity, B, and McGowan's characteristic volume, V, to model transfer properties between condensed phases. The V descriptor is assigned from structure. For compounds liquid at 20 °C the E descriptor can be assigned from the characteristic volume and its refractive index. The E descriptor for compounds solid at 20 °C and the S, A, and B descriptors are experimental properties traditionally assigned from chromatographic, liquid-liquid partition, and solubility measurements. In this report liquid-liquid partition constants in totally organic and aqueous biphasic systems are evaluated as a standalone technique for descriptor assignments. Using six totally organic biphasic systems the S, A, and B descriptors were assigned with an average absolute deviation (AAD) of about 0.04, 0.03, and 0.04, respectively, compared with the best estimate of the true descriptor values for 65 compounds. The E descriptor for compounds solid at 20 °C can only be estimated with an AAD of approximately 0.1. For six aqueous biphasic systems the B descriptor is assigned with a lower AAD of 0.028 and higher AAD of 0.08 and 0.05 for the S and A descriptors, respectively, than for the totally organic biphasic systems for compounds with a reliable value for the E descriptor. The preferred system for descriptor assignments utilizes both totally organic biphasic systems (heptane-1,1,1-trifluoroethanol, isopentyl ether-propylene carbonate, isopentyl ether-ethanolamine, heptane-ethylene glycol, heptane-formamide, and 1,2-dichloroethane-ethylene glycol) and aqueous biphasic systems (octanol-water, cyclohexane-water) with the possible substitution of some systems with alternative systems of similar selectivity. For 55 varied compounds this combination of eight organic and aqueous biphasic systems resulted in an AAD of approximately 0.03, 0.02, and 0.02 for the S, A, and B descriptors compared to the best estimate of the true descriptor value. For 30 compounds solid at 20 °C the AAD for the E descriptor of 0.11 is poorly assigned. The relative average absolute deviation in percent (RAAD) corresponds to 9.7 %, 3.1 %. 4.0 % and 8.3 % for E, S, A, and B, respectively, for the eight biphasic systems. Liquid-liquid partition is compared to reversed-phase liquid and gas chromatography as a standalone technique for descriptor assignments.


Assuntos
Éteres , Água , Etilenoglicóis , Heptanos/química , Hidrogênio , Água/química , Cicloexanos/química , Octanóis/química
7.
Environ Monit Assess ; 196(5): 435, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587761

RESUMO

Simple and sensitive electrochemical sensors were fabricated from cerium oxide (CeO2) and copper-benzene tricarboxylic acid-modified cerium oxide (CeO2-Cu-BTC) materials for differential pulse voltammetric analysis of toxic cadmium (Cd) ions in aqueous solutions. The materials were prepared by hydrothermal method and structurally characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy with energy-dispersive X-ray (SEM-EDX), thermogravimetric analysis (TGA), and X-ray diffraction analysis (XRD). The CeO2-modified carbon paste electrode (CeCPE) and the CeO2-Cu-BTC-modified carbon paste electrode (CeBCPE) were electrochemically characterized by their cyclic voltammetry and electrochemical impedance study in standard K3[Fe(CN)6] single-electron redox process. Their electrochemical surface areas, electrode surface coverages, and charge transfer resistances were calculated to be 1.46 cm2, 2.338 × 10-5 mol∙cm-2, and 2790 Ω and 5.48 cm2, 2.476 × 10-5 mol∙cm-2, and 1254.65 Ω for CeCPE and CeBCPE, respectively. These fabricated electrodes were used as electrochemical sensors for cadmium ion estimation by optimizing the experimental parameters through differential pulse voltammetry. The optimized conditions included 10% modifier for CeCPE and 5% modifier for CeBCPE in 0.12 M HCl solution of pH 5 as supporting electrolyte at - 1.2 V deposition for 30 s in 0.01 to 10 mg L-1 linear cadmium solution range. Under these conditions, the limit of quantification (LOQ) of 0.368 mg L-1 and 0.005 mg L-1 was calculated for CeCPE and CeBCPE electrodes, respectively. The limit of detection (LOD) was calculated to be 0.121 mg L-1 and 0.002 mg L-1 for CeCPE and CeBCPE, respectively. All the experimental results indicated that electrodes fabricated from CeO2-Cu-BTC show better performance as compared to CeO2-based electrodes. Both these types of electrochemical sensors presented good repeatability and performance in the presence of interfering ions as well. From these findings, it can also be inferred that these electrochemical sensors can provide a simple and very sensitive method for approximation of toxic cadmium ions in aqueous solutions.


Assuntos
Cádmio , Cério , Cobre , Cicloexanos , Monitoramento Ambiental , Íons , Carbono
8.
PLoS One ; 19(3): e0288953, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38489327

RESUMO

In this study, we intensively measured the longitudinal productivity and survival of 362 commercially managed honey bee colonies in Canada, over a two-year period. A full factorial experimental design was used, whereby two treatments were repeated across apiaries situated in three distinct geographic regions: Northern Alberta, Southern Alberta and Prince Edward Island, each having unique bee management strategies. In the protein supplemented treatment, colonies were continuously provided a commercial protein supplement containing 25% w/w pollen, in addition to any feed normally provided by beekeepers in that region. In the fumagillin treatment, colonies were treated with the label dose of Fumagilin-B® each year during the fall. Neither treatment provided consistent benefits across all sites and dates. Fumagillin was associated with a large increase in honey production only at the Northern Alberta site, while protein supplementation produced an early season increase in brood production only at the Southern Alberta site. The protein supplement provided no long-lasting benefit at any site and was also associated with an increased risk of death and decreased colony size later in the study. Differences in colony survival and productivity among regions, and among colonies within beekeeping operations, were far larger than the effects of either treatment, suggesting that returns from extra feed supplements and fumagillin were highly contextually dependent. We conclude that use of fumagillin is safe and sometimes beneficial, but that beekeepers should only consider excess protein supplementation when natural forage is limiting.


Assuntos
Cicloexanos , Ácidos Graxos Insaturados , Mel , Abelhas , Animais , Estações do Ano , Suplementos Nutricionais , Alberta , Sesquiterpenos
9.
Analyst ; 149(8): 2388-2398, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38462973

RESUMO

Hydrogen/deuterium exchange mass spectrometry (HDX-MS) is a versatile bioanalytical technique for protein analysis. Since the reliability of HDX-MS analysis considerably depends on the retention of deuterium labels in the post-labeling workflow, deuterium/hydrogen (D/H) back exchange prevention strategies, including decreasing the pH, temperature, and exposure time to protic sources of the deuterated samples, are widely adopted in the conventional HDX-MS protocol. Herein, an alternative and effective back exchange prevention strategy based on the encapsulation of a millimeter droplet of a labeled peptide solution in a water-immiscible organic solvent (cyclohexane) is proposed. Cyclohexane was used to prevent the undesirable uptake of water by the droplet from the atmospheric vapor through the air-water interface. Using the pepsin digest of deuterated myoglobin, our results show that back exchange kinetics of deuterated peptides is retarded in a millimeter droplet as compared to that in the bulk solution. Performing pepsin digestion directly in a water-in-oil droplet at room temperature (18-21 °C) was found to preserve more deuterium labels than that in the bulk digestion with an ice-water bath. Based on the present findings, it is proposed that keeping deuterated peptides in the form of water-in-oil droplets during the post-labelling workflow will facilitate the preservation of deuterium labels on the peptide backbone and thereby enhance the reliability of the H/D exchange data.


Assuntos
Pepsina A , Água , Deutério/química , Reprodutibilidade dos Testes , Espectrometria de Massas/métodos , Medição da Troca de Deutério/métodos , Peptídeos/química , Hidrogênio/química , Mioglobina/química , Cicloexanos
10.
Mol Cancer Ther ; 23(5): 595-605, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38530115

RESUMO

Methionine aminopeptidase type 2 (METAP2) is a ubiquitous, evolutionarily conserved metalloprotease fundamental to protein biosynthesis which catalyzes removal of the N-terminal methionine residue from nascent polypeptides. METAP2 is an attractive target for cancer therapeutics based upon its over-expression in multiple human cancers, the importance of METAP2-specific substrates whose biological activity may be altered following METAP2 inhibition, and additionally, that METAP2 was identified as the target for the anti-angiogenic natural product, fumagillin. Irreversible inhibition of METAP2 using fumagillin analogues has established the anti-angiogenic and anti-tumor characteristics of these derivatives; however, their full clinical potential has not been realized due to a combination of poor drug-like properties and dose-limiting central nervous system (CNS) toxicity. This report describes the physicochemical and pharmacological characterization of SDX-7320 (evexomostat), a polymer-drug conjugate of the novel METAP2 inhibitor (METAP2i) SDX-7539. In vitro binding, enzyme, and cell-based assays demonstrated that SDX-7539 is a potent and selective METAP2 inhibitor. In utilizing a high molecular weight, water-soluble polymer to conjugate the novel fumagillol-derived, cathepsin-released, METAP2i SDX-7539, limitations observed with prior generation, small molecule fumagillol derivatives were ameliorated including reduced CNS exposure of the METAP2i, and prolonged half-life enabling convenient administration. Multiple xenograft and syngeneic cancer models were utilized to demonstrate the anti-tumor and anti-metastatic profile of SDX-7320. Unlike polymer-drug conjugates in general, reductions in small molecule-equivalent efficacious doses following polymer conjugation were observed. SDX-7320 has completed a phase I clinical safety study in patients with late-stage cancer and is currently being evaluated in multiple phase Ib/II clinical studies in patients with advanced solid tumors.


Assuntos
Aminopeptidases , Antineoplásicos , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Animais , Aminopeptidases/antagonistas & inibidores , Aminopeptidases/metabolismo , Camundongos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Metionil Aminopeptidases/antagonistas & inibidores , Metaloendopeptidases/antagonistas & inibidores , Metástase Neoplásica , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Cicloexanos/farmacologia , Cicloexanos/química , Feminino , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Proliferação de Células/efeitos dos fármacos
12.
Environ Pollut ; 345: 123460, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38290655

RESUMO

Despite the increasing production, use, and ubiquitous occurrence of novel brominated flame retardants (NBFRs), little information is available regarding their fate in aquatic organisms. In this study, the bioaccumulation and biotransformation of two typical NBFRs, i.e., 1,2-bis (2,4,6-tribromophenoxyethane) (BTBPE) and 1,2-dibromo-4-(1,2-dibromoethyl)-cyclohexane (TBECH), were investigated in tissues of zebrafish (Danio rerio) being administrated a dose of target chemicals through their diet. Linear accumulation was observed for both BTBPE and TBECH in the muscle, liver, gonads, and brain of zebrafish, and the elimination of BTBPE and TBECH in all tissues followed pseudo-first-order kinetics, with the fastest depuration rate occurring in the liver. BTBPE and TBECH showed low bioaccumulation potential in zebrafish, with biomagnification factors (BMFs) < 1 in all tissues. Individual tissues' function and lipid content are vital factors affecting the distribution of BTBPE and TBECH. Stereoselective accumulation of TBECH enantiomers was observed in zebrafish tissues, with first-eluting enantiomers, i.e. E1-α-TBECH and E1-ß-TBECH, preferentially accumulated. Additionally, the transformation products (TPs) in the zebrafish liver were comprehensively screened and identified using high-resolution mass spectrometry. Twelve TPs of BTBPE and eight TPs of TBECH were identified: biotransformation pathways involving ether cleavage, debromination, hydroxylation, and methoxylation reactions for BTBPE and hydroxylation, debromination, and oxidation processes for TBECH. Biotransformation is also a vital factor affecting the bioaccumulation potential of these two NBFRs, and the environmental impacts of NBFR TPs should be further investigated in future studies. The findings of this study provide a scientific basis for an accurate assessment of the ecological and environmental risks of BTBPE and TBECH.


Assuntos
Retardadores de Chama , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Bioacumulação , Estereoisomerismo , Biotransformação , Cicloexanos/metabolismo , Retardadores de Chama/análise
13.
Nat Commun ; 15(1): 679, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263179

RESUMO

Tetrodotoxin and congeners are specific voltage-gated sodium channel blockers that exhibit remarkable anesthetic and analgesic effects. Here, we present a scalable asymmetric syntheses of Tetrodotoxin and 9-epiTetrodotoxin from the abundant chemical feedstock furfuryl alcohol. The optically pure cyclohexane skeleton is assembled via a stereoselective Diels-Alder reaction. The dense heteroatom substituents are established sequentially by a series of functional group interconversions on highly oxygenated cyclohexane frameworks, including a chemoselective cyclic anhydride opening, and a decarboxylative hydroxylation. An innovative SmI2-mediated concurrent fragmentation, an oxo-bridge ring opening and ester reduction followed by an Upjohn dihydroxylation deliver the highly oxidized skeleton. Ruthenium-catalyzed oxidative alkyne cleavage and formation of the hemiaminal and orthoester under acidic conditions enable the rapid assembly of Tetrodotoxin, anhydro-Tetrodotoxin, 9-epiTetrodotoxin, and 9-epi lactone-Tetrodotoxin.


Assuntos
Cicloexanos , Estresse Oxidativo , Tetrodotoxina , Hidroxilação , Compostos Radiofarmacêuticos
14.
J Environ Manage ; 353: 120132, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38286067

RESUMO

The removal of volatile organic compounds (VOCs) in air is of utmost importance to safeguard both environmental quality and human well-being. However, the low aqueous solubility of hydrophobic VOCs results in poor removal in waste gas biofilters (BFs). In this study, we evaluated the addition of (bio)surfactants in three BFs (BF1 and BF2 mixture of compost and wood chips (C + WC), and BF3 filled with expanded perlite) to enhance the removal of cyclohexane and hexane from a polluted gas stream. Experiments were carried out to select two (bio)surfactants (i.e., Tween 80 and saponin) out of five (sodium dodecyl sulfate (SDS), Tween 80, surfactin, rhamnolipid and saponin) from a physical-chemical (i.e., decreasing VOC gas-liquid partitioning) and biological (i.e., the ability of the microbial consortium to grow on the (bio)surfactants) point of view. The results show that adding Tween 80 at 1 critical micelle concentration (CMC) had a slight positive effect on the removal of both VOCs, in BF1 (e.g., 7.0 ± 0.6 g cyclohexane m-3 h-1, 85 ± 2% at 163 s; compared to 6.7 ± 0.4 g cyclohexane m-3 h-1, 76 ± 2% at 163 s and 0 CMC) and BF2 (e.g., 4.3 ± 0.4 g hexane m-3 h-1, 27 ± 2% at 82 s; compared to 3.1 ± 0.7 g hexane m-3 h-1, 16 ± 4% at 82 s and 0 CMC), but a negative effect in BF3 at either 1, 3 and 9 CMC (e.g., 2.4 ± 0.4 g hexane m-3 h-1, 30 ± 4% at 163 s and 1 CMC; compared to 4.6 ± 1.0 g hexane m-3 h-1, 43 ± 8% at 163 s and 0 CMC). In contrast, the performance of all BFs improved with the addition of saponin, particularly at 3 CMC. Notably, in BF3, the elimination capacity (EC) and removal efficiency (RE) doubled for both VOCs (i.e., 9.1 ± 0.6 g cyclohexane m-3 h-1, 49 ± 3%; 4.3 ± 0.3 g hexane m-3 h-1, 25 ± 3%) compared to no biosurfactant addition (i.e., 4.5 ± 0.4 g cyclohexane m-3 h-1, 23 ± 3%; hexane 2.2 ± 0.5 g m-3 h-1, 10 ± 2%) at 82 s. Moreover, the addition of the (bio)surfactants led to a shift in the microbial consortia, with a different response in BF1-BF2 compared to BF3. This study evaluates for the first time the use of saponin in BFs, it demonstrates that cyclohexane and hexane RE can be improved by (bio)surfactant addition, and it provides recommendations for future studies in this field.


Assuntos
Saponinas , Compostos Orgânicos Voláteis , Humanos , Tensoativos/química , Hexanos , Polissorbatos , Cicloexanos , Filtração/métodos
15.
J Biomol Struct Dyn ; 42(4): 1765-1777, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37097971

RESUMO

Depressive disorders are among most common psychiatric diseases and second most common form of psychiatric illness globally. Commonly available chemical drugs used for treatment of nervous system disorders exert undesirable effects. Therefore, there is a growing need towards exploring novel antidepressants of herbal origin. Earlier, the antidepressant effect of methanolic extract of garlic has been shown. In this study, the ethanolic extract of garlic was prepared and chemically analysed using Gas Chromatography - Mass Spectrometry (GC-MS) screening. A total of 35 compounds were found to be present, which might act as antidepressant. Using computational analyses, these compounds were screened as potential inhibitors (selective serotonin reuptake inhibitor (SSRI)) against serotonin transporter (SERT)/leucine receptor (LEUT). In silico docking studies and other physicochemical, bioactivity and ADMET studies resulted in the selection of compound 1 ((2-Cyclohexyl-1-methylpropyl) cyclohexane) as potential SSRI (binding energy -8.1 kcal/mol) compared to known reference SSRI fluoxetine (binding energy -8.0 kcal/mol). Analysis of conformational stability, residue flexibility, compactness, binding interactions, solvent accessible surface area (SASA), dynamic correlation, and binding free energy predicted from molecular mechanics (MD) with generalised Born and surface area solvation (MM/GBSA) studies revealed formation of a more stable SSRI like complex with compound 1 having strong inhibitory interaction compared to known SSRI fluoxetine/reference complex. Thus, compound 1 may act as an active SSRI leading to discovery of potential antidepressant drug.Communicated by Ramaswamy H. Sarma.


Assuntos
Fluoxetina , Alho , Fluoxetina/farmacologia , Simulação de Dinâmica Molecular , Antidepressivos/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Cicloexanos , Simulação de Acoplamento Molecular
16.
J Environ Manage ; 351: 119795, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38091735

RESUMO

A carbon trading market (CTM) policy for trading carbon dioxide emission rights as a commodity was created to reduce greenhouse gas emissions. CTMs operate differently in different countries and regions, and their interactions deserve an in-depth study. This study focused on the world's largest CTM, the European Union (EU), and the CTM of China, largest carbon-emitting country. First, we evaluate the liquidity and volatility of the two CTMs. Subsequently, the VAR model is used to explore the mean spillover effect between the two markets and the BEKK-GARCH model is used to explore the volatility spillover effect between the two markets. The study concludes that: (1) The liquidity of China's CTM is better than that of the EU's CTM. (2) Both the EU and Chinese CTMs are unstable, but the volatility of the Chinese CTM is lower than that of the EU CTM. (3) Price changes in the EU and Hubei CTMs have a mutual influence. (4) There are interactions between the market fluctuations of the EU CTM and the Shanghai CTM and those of the EU CTM and the Hubei CTM. The results of this study have implications for the construction and development of CTMs in the EU and China.


Assuntos
Cicloexanos , Mesilatos , China , União Europeia
17.
Chemosphere ; 349: 140900, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065261

RESUMO

Management of growing volumes of fluid fine tailings (FFT) is a significant challenge for oil sands industry. A potential alternative non-aqueous solvent extraction (NAE) process uses cycloalkane solvent such as cyclohexane or cyclopentane with very little water and generates smaller volumes of 'dry' solids (NAES) with residual solvent. Here we investigate remediation of NAES in a simulated bench-scale upland reclamation scenario. In the first study, microcosms with nutrient medium plus FFT as inoculum were amended with cyclohexane and incubated for ∼1 year, monitoring for cyclohexane biodegradation under aerobic conditions. Biodegradation of cyclohexane occurred under aerobic conditions with no metabolic intermediates detected. A second study using NAES mixed with FFT spiked with cyclohexane and cyclopentane, with or without additional nutrients (nitrogen and phosphorus), showed complete and rapid aerobic biodegradation of both cycloalkanes in NAES inoculated with FFT and supplemented with nutrients. 16S rRNA gene sequencing revealed dominance of Rhodoferax and members of Burkholderiaceae during aerobic cyclohexane biodegradation in FFT, and Hydrogenophaga, Acidovorax, Defluviimonas and members of Porticoccaceae during aerobic biodegradation of cyclohexane and cyclopentane in NAES inoculated with FFT and supplemented with nutrients. The findings indicate that biodegradation of cycloalkanes from NAES is possible under aerobic condition, which will contribute to the successful reclamation of oil sands tailings for land closure.


Assuntos
Cicloparafinas , Campos de Petróleo e Gás , RNA Ribossômico 16S , Cicloexanos , Ciclopentanos , Biodegradação Ambiental , Solventes
18.
Environ Toxicol ; 39(3): 1245-1257, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37927243

RESUMO

Diisononyl phthalate (DINP) and di(isononyl)cyclohexane-1,2-dicarboxylate (DINCH) are plasticizers introduced to replace previously used phthalate plasticizers in polymeric products. Exposure to DINP and DINCH has been shown to impact lipid metabolism. However, there are limited studies that address the mechanisms of toxicity of these two plasticizers. Here, a comparative toxicity analysis has been performed to evaluate the impacts of DINP and DINCH on 3T3-L1 cells. The preadipocyte 3T3-L1 cells were exposed to 1, 10, and 100 µM of DINP or DINCH for 10 days and assessed for lipid accumulation, gene expression, and protein analysis. Lipid staining showed that higher concentrations of DINP and DINCH can induce adipogenesis. The gene expression analysis demonstrated that both DINP and DINCH could alter the expression of lipid-related genes involved in adipogenesis. DINP and DINCH upregulated Pparγ, Pparα, C/EBPα Fabp4, and Fabp5, while both compounds significantly downregulated Fasn and Gata2. Protein analysis showed that both DINP and DINCH repressed the expression of FASN. Additionally, we analyzed an independent transcriptome dataset encompassing temporal data on lipid differentiation within 3T3-L1 cells. Subsequently, we derived a gene set that accurately portrays significant pathways involved in lipid differentiation, which we subsequently subjected to experimental validation through quantitative polymerase chain reaction. In addition, we extended our analysis to encompass a thorough assessment of the expression profiles of this identical gene set across 40 discrete transcriptome datasets that have linked to diverse pathological conditions to foreseen any potential association with DINP and DINCH exposure. Comparative analysis indicated that DINP could be more effective in regulating lipid metabolism.


Assuntos
Ácidos Cicloexanocarboxílicos , Ácidos Ftálicos , Animais , Camundongos , Plastificantes/toxicidade , Metabolismo dos Lipídeos , Células 3T3-L1 , Ácidos Cicloexanocarboxílicos/toxicidade , Ácidos Dicarboxílicos/toxicidade , Ácidos Ftálicos/toxicidade , Cicloexanos , Lipídeos
19.
Int J Environ Health Res ; 34(2): 968-978, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36966491

RESUMO

Detection of pesticide residues in soil samples was conducted using UHPLC-MS/MS. Non-dietary health risk assessment was conducted using calculate chronic daily intake (CDI) from ingestion, inhalation and dermal contact pathways and following non-carcinogenic and carcinogenic risks in the adults and adolescent. The rank order of pesticide in soil based on their concentration was malathion (0.082 mg kg-1)> cyproconazole (0.019 mg kg-1)> propargite (0.018 mg kg-1)> butachlor (0.016 mg kg-1) > chlorpyrifos (0.0067 mg kg-1)> diazinon (0.0014 mg kg-1)> imidacloprid (0.0007 mg kg-1). Hazard index (HI) values obtained of exposure to pesticides in soil in adults and adolescent were 0.0012 and 0.0035, respectively. Hence, exposed population are at the acceptable range of non-carcinogenic risk (HI < 1). Cancer risk (CR) values due to propargite in soil via ingestion pathway in adults and adolescent were 2.03E-09 and 2.08E-09, respectively; therefore, carcinogenic risk due to the exposure to pesticide contaminated soil was safe range (CR < 1E-06).


Assuntos
Cicloexanos , Resíduos de Praguicidas , Praguicidas , Poluentes do Solo , Adulto , Adolescente , Humanos , Resíduos de Praguicidas/toxicidade , Resíduos de Praguicidas/análise , Solo/química , Fazendas , Irã (Geográfico) , Espectrometria de Massas em Tandem , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Praguicidas/toxicidade , Medição de Risco , Carcinógenos/análise
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