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1.
Front Endocrinol (Lausanne) ; 15: 1336357, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586464

RESUMO

Objectives: Chronic low-grade inflammation is widely recognized as a pathophysiological defect contributing to ß-cell failure in type 2 diabetes mellitus (T2DM). Statin therapy is known to ameliorate CD8+ T cell senescence, a mediator of chronic inflammation. However, the additional immunomodulatory roles of ezetimibe are not fully understood. Therefore, we investigated the effect of statin or statin/ezetimibe combination treatment on T cell senescence markers. Methods: In this two-group parallel and randomized controlled trial, we enrolled 149 patients with T2DM whose low-density lipoprotein cholesterol (LDL-C) was 100 mg/dL or higher. Patients were randomly assigned to either the rosuvastatin group (N=74) or the rosuvastatin/ezetimibe group (N=75). The immunophenotype of peripheral blood mononuclear cells and metabolic profiles were analyzed using samples from baseline and post-12 weeks of medication. Results: The fractions of CD8+CD57+ (senescent CD8+ T cells) and CD4+FoxP3+ (Treg) significantly decreased after intervention in the rosuvastatin/ezetimibe group (-4.5 ± 14.1% and -1.2 ± 2.3%, respectively), while these fractions showed minimal change in the rosuvastatin group (2.8 ± 9.4% and 1.4 ± 1.5%, respectively). The degree of LDL-C reduction was correlated with an improvement in HbA1c (R=0.193, p=0.021). Changes in the CD8+CD57+ fraction positively correlated with patient age (R=0.538, p=0.026). Notably, the fraction change in senescent CD8+ T cells showed no significant relationship with changes in either HbA1c (p=0.314) or LDL-C (p=0.592). Finally, the ratio of naïve to memory CD8+ T cells increased in the rosuvastatin/ezetimibe group (p=0.011), but not in the rosuvastatin group (p=0.339). Conclusions: We observed a reduction in senescent CD8+ T cells and an increase in the ratio of naive to memory CD8+ T cells with rosuvastatin/ezetimibe treatment. Our results demonstrate the immunomodulatory roles of ezetimibe in combination with statins, independent of improvements in lipid or HbA1c levels.


Assuntos
Anticolesterolemiantes , Azetidinas , Diabetes Mellitus Tipo 2 , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipercolesterolemia , Humanos , Rosuvastatina Cálcica/uso terapêutico , Ezetimiba/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , LDL-Colesterol , Anticolesterolemiantes/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas , Leucócitos Mononucleares , Hipercolesterolemia/tratamento farmacológico , Azetidinas/uso terapêutico , Fluorbenzenos/uso terapêutico , Pirimidinas , Sulfonamidas/uso terapêutico , Quimioterapia Combinada , Resultado do Tratamento , Inflamação/tratamento farmacológico , Linfócitos T
2.
Eur J Pharmacol ; 969: 176466, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431243

RESUMO

The chronic use of the novel synthetic cathinone mexedrone, like other psychoactive drugs, can be considered addictive, with a high potential for abuse and the ability to cause psychological dependence in certain users. However, little is known about the neurobehavioral effects of mexedrone in association with its potential for abuse. We investigated the abuse potential for mexedrone abuse through multiple behavioral tests. In addition, serotonin transporter (SERT) levels were measured in the synaptosome of the dorsal striatum, and serotonin (5-HT) levels were measured in the dorsal striatum of acute mexedreone (50 mg/kg)-treated mice. To clarify the neuropharmacological mechanisms underlying the locomotor response of mexedrone, the 5-HT2A receptor antagonist M100907 (0.5 or 1.0 mg/kg) was administered prior to the acute injection of mexedrone in the locomotor activity experiment in mice. Mexedrone (10-50 mg/kg) produced a significant place preference in mice and mexedrone (0.1-0.5 mg/kg/infusion) maintained self-administration behavior in rats in a dose-dependent manner. In the drug discrimination experiment, mexedrone (5.6-32 mg/kg) was fully substituted for the discriminative stimulus effects of cocaine in rats. Mexedrone increased locomotor activity, and these effects were reversed by pretreatment with M100907. Acute mexedrone significantly increased c-Fos expression in the dorsal striatum and decreased SERT levels in the synaptosome of the dorsal striatum of mice, resulting in an elevation of 5-HT levels. Taken together, our results provide the possibility that mexedrone has abuse potential, which might be mediated, at least in part, by the activation of the serotonergic system in the dorsal striatum.


Assuntos
Cocaína , Fluorbenzenos , Metanfetamina/análogos & derivados , Piperidinas , Catinona Sintética , Ratos , Camundongos , Masculino , Animais , Ratos Sprague-Dawley , Serotonina/metabolismo , Cocaína/farmacologia , Relação Dose-Resposta a Droga
3.
Talanta ; 273: 125816, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38442561

RESUMO

The refinement and optimization of a method combining headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) was successfully performed for the first time to determine seven carbonyl and dicarbonyl compounds, including glyoxal, methylglyoxal, dimethylglyoxal, and malondialdehyde in infant formulae, related to lipid peroxidation. HS-SPME was utilized for simultaneous extraction and derivatization with pentafluorophenylhydrazine (PFPH). Critical parameters such as temperature, pH, extractive phase, and salting-out were meticulously investigated and fine-tuned by an asymmetrical 2232//9 screening design to ensure the method's efficacy and reliability. Optimal conditions included a PFPH concentration of 5 g/L, pH 5.0, head-space extraction at 60 °C within 10 min, utilizing a DVB/CAR/PDMS coating, and a 20% w/w salting-out. The analytical validation of this method, compliant with FDA guidelines, demonstrated exceptional linearity, sensitivity, specificity, precision (RSD ≤13.8%), and accuracy (84.8% ≤ recovery ≤111.5%). The metric approach AGREEprep confirms its eco-friendliness, marking a significant step towards an environmentally conscious approach in infant formula analysis. An occurrence study conducted on 25 infant formula samples revealed widespread carbonyl and dicarbonyl compounds in both powdered and liquid variants. ANOVA results exhibited variations in compound concentrations among different sample groups. Clustering analyses delineated distinct groups based on carbonyl content, indicating the potential of these compounds as markers for lipid peroxidation and food quality assessment. This method serves as a valuable tool for evaluating infant formula quality, stability towards oxidation, and safety.


Assuntos
Fluorbenzenos , Fluorocarbonos , Hidrazinas , Fórmulas Infantis , Microextração em Fase Sólida , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Peroxidação de Lipídeos , Reprodutibilidade dos Testes , Compostos Orgânicos
4.
Malar J ; 23(1): 31, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254131

RESUMO

BACKGROUND: The emergence of insecticide resistance and outdoor transmission in malaria-endemic areas underlines the urgent need to develop innovative tools, such as spatial repellents (SR), that may circumvent this residual transmission. With limited options for effective insecticides, regular resistance monitoring is warranted for selecting and using appropriate tools. This study evaluates the pyrethroid knockdown resistance (kdr) allele before and after implementing a transfluthrin-based spatial repellent (SR) intervention in placebo-treated clusters. METHODS: This study looks at the frequency distribution of the kdr allele in Sumba Island from June 2015 to August 2018. Insecticide susceptibility tests were carried out on female Anopheles sp. aged 3-5 days against permethrin 21.5 µg/ml, deltamethrin 12.5 µg/ml, and transfluthrin 10 µg/ml using CDC bottle assay. PCR sequencing of representative samples from adult mosquito collections and insecticide tests revealed the presence of kdr mutations (L1014F and L1014S) in the VGSC gene. RESULTS: A total of 12 Anopheles species, Anopheles tesselatus, Anopheles. aconitus, Anopheles barbirostris, Anopheles kochi, Anopheles annularis, Anopheles maculatus, Anopheles sundaicus, Anopheles flavirostris, Anopheles balabacensis, Anopheles indefinitus, Anopheles subpictus, and Anopheles vagus were analysed. Anopheles vagus and An. sundaicus predominated in the larval populations. Susceptibility assays for all insecticides identified fully susceptible phenotypes in all species examined. Anopheles increasing frequency of kdr mutant alleles during the 3 year SR deployment was observed in both SR-treated and placebo areas, a statistically significant increase occurred in each arm. However, it is unclear how significant SR is in causing the increase in mutant alleles. The L1014S, knockdown resistance east type (kdr-e) allele was detected for the first time among the mosquito samples in this study. The L1014F, knockdown resistance west type (kdr-w) allele and heteroduplex form (wild-type-mutant) were found in almost all Anopheles species examined, including An. vagus, An. aconitus, An. subpictus, An. tesselatus, An. annularis, An. flavirostris and An. sundaicus. CONCLUSION: The presence of fully susceptible phenotypes over time, along with an increase in the frequency distribution of the L1014F/S mutations post-intervention, suggest drivers of resistance external to the study, including pyrethroid use in agriculture and long-lasting insecticidal nets (LLINs). However, this does not negate possible SR impacts that support resistance. More studies that enable the comprehension of possible SR-based drivers of resistance in mosquitoes need to be conducted.


Assuntos
Anopheles , Ciclopropanos , Fluorbenzenos , Inseticidas , Animais , Feminino , Anopheles/genética , Inseticidas/farmacologia , Alelos , Indonésia , Resistência a Inseticidas/genética , Permetrina
5.
Eur J Pharmacol ; 966: 176329, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38253116

RESUMO

The anxiolytic and sedative-like effects of 3-methyl-1,2,3,4,5,6-hexahydroazepino[4,5-b]indole (DM506), a non-hallucinogenic compound derived from ibogamine, were studied in mice. The behavioral effects were examined using Elevated O-maze and novelty suppressed feeding (NSFT) tests, open field test, and loss of righting reflex (LORR) test. The results showed that 15 mg/kg DM506 induced acute and long-lasting anxiolytic-like activity in naive and stressed/anxious mice, respectively. Repeated administration of 5 mg/kg DM506 did not cause cumulative anxiolytic activity or any side effects. Higher doses of DM506 (40 mg/kg) induced sedative-like activity, which was inhibited by a selective 5-HT2A receptor antagonist, volinanserin. Electroencephalography results showed that 15 mg/kg DM506 fumarate increased the transition from a highly alert state (fast γ wavelength) to a more synchronized deep-sleeping activity (δ wavelength), which is reflected in the sedative/anxiolytic activity in mice but without the head-twitch response observed in hallucinogens. The functional, radioligand binding, and molecular docking results showed that DM506 binds to the agonist sites of human 5-HT2A (Ki = 24 nM) and 5-HT2B (Ki = 16 nM) receptors and activates them with a potency (EC50) of 9 nM and 3 nM, respectively. DM506 was relatively less potent and behaved as a partial agonist (efficacy <80%) for both receptor subtypes compared to the full agonist DOI (2,5-dimethoxy-4-iodoamphetamine). Our study showed for the first time that the non-hallucinogenic compound DM506 induces anxiolytic- and sedative-like activities in naïve and stressed/anxious mice in a dose-, time-, and volinanserin-sensitive manner, likely through mechanisms involving 5-HT2A receptor activation.


Assuntos
Ansiolíticos , Fluorbenzenos , Piperidinas , Animais , Humanos , Camundongos , Ansiolíticos/farmacologia , Comportamento Animal , Hipnóticos e Sedativos/farmacologia , Simulação de Acoplamento Molecular , Receptor 5-HT2A de Serotonina , Serotonina/metabolismo
6.
J Med Entomol ; 61(2): 427-441, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38284470

RESUMO

WHO tube and CDC bottle bioassays are currently available for insecticide resistance monitoring and malaria transmission research. Multiple parameters including mosquito density, age, and nutritional status may affect the readout in these bioassays' tests. This study aims to assess the effects of experimental factors on knockdown and mortality measurements in dominant malaria vectors in Thailand following exposure to sublethal and lethal doses of transfluthrin. The effects of (i) 3 different mosquito batch sizes (5, 10, and 20 individuals) and (ii) 2 age groups (3-5 and 20-23 days old) on outcomes measured using the WHO tube (14.7 µg/cm2) and CDC bottle bioassay discriminating concentration (0.006 µg/cm2) against 2 laboratory strains: Anopheles dirus Peyton & Harrison and Anopheles minimus Theobald (species A) and wild-caught Anopheles harrisoni Harbach & Manguin (species C). Our results showed higher knockdown at 1-h exposure using WHO tube and CDC bottle bioassays containing 20 individuals compared to batches containing 10 and 5 individuals. Older mosquitoes showed greater susceptibility than younger test population, especially for An. mininus. Our study supports WHO recommendations for using 3- to 5-day-old mosquitoes. It also validates Praulin et al. (2022) proposal to divide the cohort into smaller batches with more test replicates when it is not practicable to test 25 mosquitoes per replicate.


Assuntos
Anopheles , Ciclopropanos , Fluorbenzenos , Inseticidas , Malária , Piretrinas , Humanos , Animais , Estados Unidos , Mosquitos Vetores , Resistência a Inseticidas , Bioensaio , Centers for Disease Control and Prevention, U.S. , Organização Mundial da Saúde , Inseticidas/farmacologia , Controle de Mosquitos/métodos , Piretrinas/farmacologia
7.
J Med Entomol ; 61(1): 181-190, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-37936536

RESUMO

Volatile pyrethroids exert a range of both lethal and behavioral effects on mosquitoes through the passive release of insecticides into the atmosphere. We investigated the protective efficacy (PE) of transfluthrin-treated jute (TI-jute) and cotton (TI-cotton) fabrics, worn at the back of a protective black vest, against laboratory-reared pyrethroid susceptible and resistant strains of Aedes aegypti (L.) in a semifield system (SFS). Each fabric (1,029 cm2) was treated with 1.79 mg/cm2 of transfluthrin as the intervention. Human landing collections were conducted by 2 collectors seated in designated treatment and control compartments of the SFS. The trials were conducted for 41 days, with 16 days partitioned into morning and evening phases. Furthermore, we examined blood feeding behavior and fecundity of the surviving mosquitoes post-exposure. Results showed that in the morning, the PE of TI-jute (49.4%) was higher than that of TI-cotton (36.8%). TI-jute demonstrated a lower PE of 9.6% against the transfluthrin-resistant strain. Remarkably, a significantly higher number of eggs were laid by the transfluthrin-resistant mosquitoes that survived the intervention (36.5 eggs/female) compared to the control group (11.8 eggs/female). These findings suggest that TI-jute can help protect against bites and alter the life traits of Ae. aegypti. The study highlights that the timing of the intervention during the day affected the efficacy of TI-jute and TI-cotton, while sublethal exposure to transfluthrin stimulated egg production in the resistant strain. These are critical challenges that warrant attention in vector control strategies. Investigating this phenomenon in mosquito reproduction necessitates future research at a molecular level.


Assuntos
Aedes , Ciclopropanos , Fluorbenzenos , Repelentes de Insetos , Inseticidas , Piretrinas , Feminino , Animais , Humanos , Mosquitos Vetores , Inseticidas/farmacologia , Piretrinas/farmacologia , Vestuário , Controle de Mosquitos/métodos , Repelentes de Insetos/farmacologia
8.
J Mol Graph Model ; 127: 108693, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38070228

RESUMO

Ab initio molecular dynamics studies have been performed on fluorobenzene, phenol, and aniline, which have the three most electronegative atoms, fluorine, oxygen, and nitrogen, respectively. Radial distribution functions show strong hydrogen bonding in the phenolic -OH group, whereas it is less prominent in the -NH2 group of aniline. Fluorobenzene does not show strong hydrogen bonds as no solvation shell is found between the fluorine atom and different aromatic hydrogens of the molecule. Spatial distribution functions show that the nitrogen atom of aniline interacts with the aromatic plane, the oxygen atom of phenol is concentrated near the -OH group and fluorobenzene's fluorine atom interacts with the para hydrogen. Liquid phase dimer structures of these systems reveal that perpendicular orientation (Y-shaped) is preferred over parallel ones. Almost half of the total dimer population tends to prefer 90∘±30° angle. H-bond analyses show that fluorobenzene has the longest mean H-bond lifetime for the H-bond between the aromatic hydrogens and the fluorine atoms, whereas the aniline has the least. The mean lifetime between aromatic hydrogens and electronegative atoms increases steadily from aniline to fluorobenzene. Phenolic -OH and amino -NH2 groups show considerably longer mean H-bond lifetime than the aromatic hydrogens. Gas-phase binding energies obtained from quantum chemical calculations show that aniline and phenol dimers have higher binding energy values than the fluorobenzene dimer. Only the phenol dimer shows a perpendicular structure as a stable one, while aniline and fluorobenzene prefer the parallel orientation.


Assuntos
Flúor , Fluorbenzenos , Ligação de Hidrogênio , Fenol/química , Compostos de Anilina , Oxigênio , Nitrogênio
9.
Org Biomol Chem ; 22(2): 364-373, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38086694

RESUMO

Substitution of two fluorine atoms of the tetrafluoroterephthalonitrile (TFTN) ring (ortho to each other) by amine nucleophiles through SNAr chemistry is achievable. However, tri- and tetra-substitution towards multi-substituted single benzene fluorophores (SBFs) is harder due to increased electron richness of the TFTN moiety. Tertiary amine donors promote the molecule towards such multi-substitution guided by the steric obstruction to intramolecular charge transfer to the TFTN ring. Contrarily, secondary amine substituents with better lone pair donation to the TFTN ring cannot induce the SNAr pathway and instead promote hydrolysis of the nitrile groups of the TFTN moiety. Theoretical investigations have helped unearth the reasons for this observed difference in chemical reactivities and also explain the differences in the emission spectra. Finally, the success of the synthetic method towards multi-substitution is showcased through creation of a highly lipophilic SBF bearing an octyl unit and demonstrating its utility in in vitro cellular imaging.


Assuntos
Aminas , Benzeno , Aminas/química , Flúor/química , Fluorbenzenos
10.
Eur J Pharm Sci ; 190: 106576, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37678518

RESUMO

BACKGROUND AND OBJECTIVE: Hyzetimibe is a cholesterol absorption inhibitor indicated for the treatment of hypercholesterolemia. This study aims to describe the multiple-peak pharmacokinetics (PK) of hyzetimibe and its active metabolite M1 through physiologically-based pharmacokinetic (PBPK) modeling, and to compare the model predictions of a virtual food effect study with the results of a clinical food effect study. METHODS: The plasma concentration data used for PBPK modeling were obtained from a single-dose, two-period crossover bioequivalence study in the fasted state. Advanced Compartmental Absorption and Transit model was used for absorption. Enterohepatic recirculation process was modeled by changing the gut physiological state from fasted to fed at meal time. Based on the established PBPK models, a virtual food effect study was simulated. A clinical food effect study was used for model external validation. RESULTS: PK profiles of hyzetimibe and M1 under fasting condition could be well described by the PBPK model, and the errors of Cmax, AUC0-∞, and AUC0-t were within the two-fold range. Simulated geometric mean ratios (GMRs, fed/fasted) showed that a high-fat breakfast slightly affected the PK of hyzetimibe, expressed as increased Cmax of hyzetimibe (130.6%). Simulated GMRs and 90% confidence intervals of AUC were within the preset bioequivalent range. The results of the simulated virtual food effect trial were consistent with those of the clinical food effect trial. CONCLUSIONS: The established PBPK model could describe the concentration-time profiles of hyzetimibe and M1 well with good prediction performance. A fully mechanistic model of enterohepatic recirculation warrants further investigation.


Assuntos
Anticolesterolemiantes , Azetinas , Fluorbenzenos , Jejum/metabolismo , Equivalência Terapêutica , Estudos Cross-Over , Área Sob a Curva , Voluntários Saudáveis
11.
Environ Sci Technol ; 57(29): 10773-10781, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37428517

RESUMO

Anaerobic bacteria transform aromatic halides through reductive dehalogenation. This dehalorespiration is catalyzed by the supernucleophilic coenzyme vitamin B12, cob(I)alamin, in reductive dehalogenases. So far, the underlying inner-sphere electron transfer (ET) mechanism has been discussed controversially. In the present study, all 36 chloro-, bromo-, and fluorobenzenes and full-size cobalamin are analyzed at the quantum chemical density functional theory level with respect to a wide range of theoretically possible inner-sphere ET mechanisms. The calculated reaction free energies within the framework of CoI···X (X = F, Cl, and Br) attack rule out most of the inner-sphere pathways. The only route with feasible energetics is a proton-coupled two-ET mechanism that involves a B12 side-chain tyrosine (modeled by phenol) as a proton donor. For 12 chlorobenzenes and 9 bromobenzenes with experimental data from Dehalococcoides mccartyi strain CBDB1, the newly proposed PC-TET mechanism successfully discriminates 16 of 17 active from 4 inactive substrates and correctly predicts the observed regiospecificity to 100%. Moreover, fluorobenzenes are predicted to be recalcitrant in agreement with experimental findings. Conceptually, based on the Bell-Evans-Polanyi principle, the computational approach provides novel mechanistic insights and may serve as a tool for predicting the energetic feasibility of reductive aromatic dehalogenation.


Assuntos
Chloroflexi , Chloroflexi/metabolismo , Fluorbenzenos/metabolismo , Prótons , Vitamina B 12/metabolismo , Biodegradação Ambiental
12.
Adv Med Sci ; 68(2): 258-264, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37478516

RESUMO

PURPOSE: For many years, statins have been the most commonly used drugs in cholesterol-lowering therapy. In addition to these therapeutic effects, statins exhibit other, pleiotropic effects that can be beneficial, but also harmful to cells and tissues. The aim of this research was to determine and compare the pleiotropic effects of structurally different statins: atorvastatin, simvastatin and rosuvastatin at different concentrations on hepatocellular carcinoma (HepG2) cells. MATERIALS AND METHODS: The MTT assay was used to determine the cytotoxic effects of statins. The influence of statins on the production of reactive oxygen species (ROS) was determined by measuring fluorescent response of 2,7-dichlorofluorescein diacetate (DCFH-DA). The effect of statins on glucose production and excretion was determined with glucose production assay. RESULTS: The obtained results confirmed that all tested statins exhibit cytotoxic effects, increase the production of ROS as well as the production and excretion of glucose from HepG2 cells. It was observed that all the mentioned effects are more pronounced with lipophilic statins, atorvastatin and simvastatin compared to hydrophilic rosuvastatin. CONCLUSION: The less pronounced pleiotropic effects of rosuvastatin on HepG2 cells are probably due to differences in structure and solubility compared to atorvastatin and simvastatin. Transporter-dependent and a slower influx of rosuvastatin into cells compared to the tested lipophilic statins probably lead to a weaker accumulation of rosuvastatin in HepG2 cells, which results in less pronounced pleiotropic effects compared to lipophilic atorvastatin and simvastatin.


Assuntos
Carcinoma Hepatocelular , Ácidos Heptanoicos , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Hepáticas , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Rosuvastatina Cálcica/farmacologia , Atorvastatina/farmacologia , Sinvastatina/farmacologia , Sinvastatina/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Espécies Reativas de Oxigênio , Ácidos Heptanoicos/uso terapêutico , Pirróis/uso terapêutico , Fluorbenzenos/uso terapêutico , Pirimidinas/uso terapêutico , Sulfonamidas/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Glucose
13.
J Org Chem ; 87(23): 16039-16046, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36379013

RESUMO

Pd-catalyzed borylation of fluorobenzene was theoretically studied. DFT calculations revealed that the reaction occurs through an unprecedented 3 + 6-membered ring transition state, in which one LiHMDS (HMDS = hexamethyldisilazane) acts as a ligand and another LiHMDS is essential to provide Li···N and Li···F interactions, overcoming the large destabilization of the strong phenyl-F bond distortion. The characteristic feature of LiHMDS was elucidated by comparing it with HMDS and NaHMDS analogues.


Assuntos
Fluorbenzenos , Paládio , Paládio/química , Modelos Moleculares , Ligantes
14.
Acta Crystallogr D Struct Biol ; 78(Pt 10): 1221-1234, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36189742

RESUMO

Enzymes catalyze reactions by binding and orienting substrates with dynamic interactions. Horse liver alcohol dehydrogenase catalyzes hydrogen transfer with quantum-mechanical tunneling that involves fast motions in the active site. The structures and B factors of ternary complexes of the enzyme with NAD+ and 2,3,4,5,6-pentafluorobenzyl alcohol or NAD+ and 2,2,2-trifluoroethanol were determined to 1.1-1.3 Šresolution below the `glassy transition' in order to extract information about the temperature-dependent harmonic motions, which are reflected in the crystallographic B factors. The refinement statistics and structures are essentially the same for each structure at all temperatures. The B factors were corrected for a small amount of radiation decay. The overall B factors for the complexes are similar (13-16 Å2) over the range 25-100 K, but increase somewhat at 150 K. Applying TLS refinement to remove the contribution of pseudo-rigid-body displacements of coenzyme binding and catalytic domains provided residual B factors of 7-10 Å2 for the overall complexes and of 5-10 Å2 for C4N of NAD+ and the methylene carbon of the alcohols. These residual B factors have a very small dependence on temperature and include local harmonic motions and apparently contributions from other sources. Structures at 100 K show complexes that are poised for hydrogen transfer, which involves atomic displacements of ∼0.3 Šand is compatible with the motions estimated from the residual B factors and molecular-dynamics simulations. At 298 K local conformational changes are also involved in catalysis, as enzymes with substitutions of amino acids in the substrate-binding site have similar positions of NAD+ and pentafluorobenzyl alcohol and similar residual B factors, but differ by tenfold in the rate constants for hydride transfer.


Assuntos
Álcool Desidrogenase , NAD , Álcool Desidrogenase/química , Álcool Desidrogenase/metabolismo , Aminoácidos/química , Animais , Álcoois Benzílicos/química , Álcoois Benzílicos/metabolismo , Sítios de Ligação , Carbono , Cristalografia por Raios X , Fluorbenzenos , Fluorocarbonos , Cavalos , Hidrogênio/química , Cinética , Fígado , NAD/química , Conformação Proteica , Temperatura , Trifluoretanol/química , Trifluoretanol/metabolismo
15.
Forensic Sci Int ; 340: 111450, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36152449

RESUMO

In this study, fluorine-19 nuclear magnetic resonance spectroscopy (19F NMR) served as a highly specific tool for identification of fluorinated new psychoactive substances (NPS) as well as a suitable analytical method for the accurate quantification of fluorinated NPS in different seized samples. In the first part of the study, 19F NMR spectroscopy of a number of different fluorinated NPS, including 51 synthetic cannabinoids, 8 synthetic cathinones, 7 phenethylamines, 8 fentanyl analogues, and 9 other types of compounds was conducted. The chemical shifts and multiplet of the primary fluorides (RCH2F), fluorobenzenes (ortho-ArF, meta-ArF, and para-ArF), and trifluoromethylbenzenes (ArCF3) were discussed in detail to illustrate the role of 19F signals as special fingerprints in assisting the structure identification of fluorine-containing NPS. To the best of our knowledge, this study is the largest evaluation of fluorinated NPS compounds by 19F NMR. The second part of this study dealt with the problems encountered in the 19F quantification procedure and the criteria to be considered for successful quantification by 19F NMR. General high field (HF)- and low field (LF)- 19F qNMR methods for the quantification of fluorinated NPS were established after the thorough discussion of NMR spectrum acquisition and processing parameters such as: transmitter frequency offset (O1P), spin-lattice relaxation time (T1), and different baseline correction methods. The limit of quantifications (LOQs) for HF-19F qNMR varied between 0.1 mg/mL and 0.2 mg/mL, and for LF-19F qNMR varied between 1.0 mg/mL and 2.0 mg/mL. The limit of detections (LODs) for HF-19F qNMR varied between 0.03 mg/mL and 0.06 mg/mL, and for LF-19F qNMR varied between 0.3 mg/mL and 0.6 mg/mL. Finally, the developed methods were applied for the quantification of fluorinated-NPS in seventeen herbal blends, e-liquid, tablet, and powder NPS seizures.


Assuntos
Canabinoides , Flúor , Fármacos do Sistema Nervoso Central , Fentanila , Fluoretos , Flúor/química , Fluorbenzenos , Espectroscopia de Ressonância Magnética/métodos , Fenetilaminas , Pós
16.
Neurosci Lett ; 788: 136836, 2022 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-35963476

RESUMO

Psychedelics, also known as classical hallucinogens, affect processes related to perception, cognition and sensory processing mostly via the serotonin 5-HT2A receptor (5-HT2AR). This class of psychoactive substances, which includes lysergic acid diethylamide (LSD), psilocybin, mescaline and the substituted amphetamine 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), is receiving renewed attention for their potential therapeutic properties as it relates to psychiatric conditions such as depression and substance use disorders. Current studies focused on the potentially clinical effects of psychedelics on human subjects tend to exclude sex as a biological variable. Much of the understanding of psychedelic pharmacology is derived from rodent models, but most of this preclinical research has only focused on male mice. Here we tested the effects of DOI on head-twitch behavior (HTR) - a mouse behavioral proxy of human psychedelic potential - in male and female mice. DOI elicited more HTR in female as compared to male C57BL/6J mice, a sex-specific exacerbated behavior that was not observed in 129S6/SvEv animals. Volinanserin (or M100907) - a 5-HT2AR antagonist - fully prevented DOI-induced HTR in male and female C57BL/6J mice. Accumulation of inositol monophosphate (IP1) in the frontal cortex upon DOI administration showed no sex-related effect in C57BL/6J mice. However, the pharmacokinetic properties of DOI differed among sexes - brain and plasma concentrations of DOI were lower 30 and 60 min after drug administration in female as compared to male C57BL/6J mice. Together, these results suggest strain-dependent and sex-related differences in the behavioral and pharmacokinetic profiles of the 5-HT2AR agonist DOI in C57BL/6J mice, and support the importance of studying sex as a biological variable in preclinical psychedelic research.


Assuntos
Alucinógenos , Anfetamina/farmacologia , Animais , Comportamento Animal , Feminino , Fluorbenzenos , Alucinógenos/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Piperidinas , Receptor 5-HT2A de Serotonina , Serotonina/farmacologia
17.
Molecules ; 27(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36014446

RESUMO

Methylmalonic acid (MMA) is a very short dicarboxylic acid (methylpropanedioic acid; CH3CH(COOH)2; pKa1, 3.07; pKa2, 5.76) associated with vitamin B12 deficiency and many other patho-physiological conditions. In this work, we investigated several carboxylic groups-specific derivatization reactions and tested their utility for the quantitative analysis of MMA in human urine and plasma by gas chromatography-mass spectrometry (GC-MS). The most useful derivatization procedure was the reaction of unlabeled MMA (d0-MMA) and trideutero-methyl malonic acid (d3-MMA) with 2,3,4,5,6-pentafluorobenzyl bromide (PFB-Br) in acetone. By heating at 80 °C for 60 min, we observed the formation of the dipentafluorobenzyl (PFB) ester of MMA (CH3CH(COOPFB)2). In the presence of N,N-diisopropylamine, heating at 80 °C for 60 min resulted in the formation of a tripentafluorobenzyl derivative of MMA, i.e., CH3CPFB(COOPFB)2). The retention time was 5.6 min for CH3CH(COOPFB)2 and 7.3 min for CH3CPFB(COOPFB)2). The most intense ions in the negative-ion chemical ionization (NICI) GC-MS spectra of CH3CH(COOPFB)2 were mass-to-charge (m/z) 233 for d0-MMA and m/z 236 for d3-MMA. The most intense ions in the NICI GC-MS spectra of CH3CPFB(COOPFB)2 were mass-to-charge (m/z) 349 for d0-MMA and m/z 352 for d3-MMA. These results indicate that the H at C atom at position 2 is C-H acidic and is alkylated by PFB-Br only in the presence of the base N,N-diisopropylamine. Method validation and quantitative analyses in human urine and plasma were performed by selected ion monitoring (SIM) of m/z 349 for d0-MMA and m/z 352 for the internal standard d3-MMA in the NICI mode. We used the method to measure the urinary excretion rates of MMA in healthy black (n = 39) and white (n = 41) boys of the Arterial Stiffness in Offspring Study (ASOS). The creatinine-corrected excretion rates of MMA were 1.50 [0.85-2.52] µmol/mmol in the black boys and 1.34 [1.02-2.18] µmol/mmol in the white boys (P = 0.85; Mann-Whitney). The derivatization procedure is highly specific and sensitive for MMA and allows its accurate and precise measurement in 10-µl of human urine by GC-MS.


Assuntos
Fluorbenzenos , Ácido Metilmalônico , Fluorbenzenos/química , Fluorocarbonos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Isótopos , Masculino
18.
Stroke ; 53(10): 3004-3013, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36017704

RESUMO

BACKGROUND: Atherosclerosis is the leading cause of cardiovascular disease worldwide, including in China. Primary prevention, through lipid-lowering, could avert development of atherosclerosis. Carotid intima-media thickness (CIMT) is a well-validated measure of atherosclerosis used in intervention studies as the primary outcome and alternative end point for cardiovascular disease events. METHODS: This randomized, double-blind, placebo-controlled, multicenter, parallel-group study assessed the effects of rosuvastatin 20 mg/d compared with placebo on progression of CIMT over 104 weeks in Chinese people with subclinical atherosclerosis. The primary end point was the annualized rate of change in mean of the maximum CIMT measurements taken 7× over the study period from each of 12 carotid artery sites (near and far walls of the right and left common carotid artery, carotid bulb, and internal carotid artery). Secondary end points included CIMT changes at different artery sites and lipid-parameter changes. Safety was also assessed. RESULTS: Participants were randomized (1:1) to receive rosuvastatin (n=272) or placebo (n=271). Baseline characteristics were well balanced between groups. The change in mean of the maximum CIMT of the 12 carotid sites was 0.0038 mm/y (95% CI, -0.0023-0.0100) for the rosuvastatin group versus 0.0142 mm/y (95% CI, 0.0080-0.0204) for the placebo group, with a difference of -0.0103 mm/y (95% CI, -0.0191 to -0.0016; P=0.020). For the CIMT secondary end points, the results were generally consistent with the primary end point. There were clinically relevant improvements in lipid parameters with rosuvastatin. We observed an adverse-event profile consistent with the known safety profile of rosuvastatin. CONCLUSIONS: Rosuvastatin 20 mg/d significantly reduced the progression of CIMT over 2 years in Chinese adults with subclinical atherosclerosis and was well tolerated. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02546323.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Doenças das Artérias Carótidas , Adulto , Aterosclerose/diagnóstico por imagem , Aterosclerose/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/tratamento farmacológico , Espessura Intima-Media Carotídea , Progressão da Doença , Fluorbenzenos/farmacologia , Fluorbenzenos/uso terapêutico , Humanos , Lipídeos/farmacologia , Lipídeos/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Rosuvastatina Cálcica/farmacologia , Rosuvastatina Cálcica/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico
19.
PLoS One ; 17(5): e0267278, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35536780

RESUMO

BACKGROUND: With the recent occurrence of locally transmitted Aedes-borne viruses in the continental United States and Europe, and a lack of effective vaccines, new approaches to control Aedes aegypti and Aedes albopictus are needed. In sub-tropical urban settings in the US, Ae. albopictus is a dominant nuisance and arbovirus vector species. Unfortunately, the vector control toolbox against Ae. albopictus is not as well developed as for Ae. aegypti. Here, we evaluate the efficacy, longevity, and range of protectiveness of a novel passive metofluthrin emanator (10% active ingredient in a polyethylene mesh) against Ae. albopictus indoors and outdoors. METHODS: Four studies were conducted comparing the presence of the metofluthrin emanator to a control lacking emanator with interest in quantifying efficacy by human landing counts. Studies evaluated the effect of an emanator at varying distances from one or more human volunteers indoors and outdoors. Efficacy of emanators over time since activation was also evaluated. RESULTS: Mixed-effects models determined that sitting in close proximity to an emanator reduced landings by 89.5% outdoors and by 74.6% indoors. The emanator was determined protective when located immediately next to a human volunteer outdoors but not uniformly protective when located further away. The emanator was protective at all tested distances from the device indoors. Mortality of mosquitoes exposed to metofluthrin emanators was ~2x higher than those who were not exposed in indoor conditions. Finally, a Generalized Additive Model determined that emanators used continuously outdoors lost their effect after 2.5 weeks and stopped inducing paralysis in mosquitoes after 3.8 weeks of use. CONCLUSIONS: We show strong and lasting efficacy of 10% metofluthrin emanators against field Ae. albopictus both in indoor and outdoor conditions. Metofluthrin emanators can protect people from Ae. albopictus bites, representing a viable option for reducing human-mosquito contacts at home and beyond.


Assuntos
Aedes , Inseticidas , Aedes/fisiologia , Animais , Ciclopropanos , Fluorbenzenos , Humanos , Inseticidas/farmacologia , Controle de Mosquitos , Mosquitos Vetores
20.
Inorg Chem ; 61(19): 7251-7255, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35486113

RESUMO

We have studied the photochemical cyclization of 1-(2-iodobenzyl)-pyrrole (IBP) and 1-(2-bromobenzyl)-pyrrole (BBP) to 5H-pyrrolo[2,1-a]isoindol catalyzed by W(CNDipp)6 (CNDipp = 2,6-diisopropylphenylisocyanide) in 1,2-difluorobenzene (DFB). Irradiation (445 nm) of W(CNDipp)6 (5 mol %) in DFB solution converted 78% of IBP (50 mM) to product after 1 h (16 turnovers). Addition of tetra-n-butyl ammonium hexafluorophosphate (TBAPF6) (0.2 M) to the DFB solution led to rapid photoinduced disappearance of W(CNDipp)6 but, remarkably, did not inhibit photochemical cyclization of IBP, indicating that IBP cyclization could be driven by a nonluminescent photocatalyst.


Assuntos
Pirróis , Tungstênio , Catálise , Ciclização , Fluorbenzenos
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