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1.
J Stomatol Oral Maxillofac Surg ; : 101808, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38423358

RESUMO

OBJECTIVE: To provide some clarity to the confusion in the terminology used to classify arthroscopic procedures for the treatment of temporomandibular joint (TMJ) internal derangement (ID) and osteoarthrosis (OA). MATERIAL AND METHODS: The author introduces a new method for categorizing TMJ arthroscopic procedures more accurately, intending to establish a reference point from which further clinical series may built their analyses. RESULTS: Six categories are proposed for establishing a clear distinction among performed arthroscopic procedures: Level Ia, arthroscopic lavage (AL); Level Ib, arthroscopic lysis and lavage (ALL); Level Ic, ALL "needle-therapy"; Level IIa, simple operative arthroscopy (OA); Level IIb, advanced OA; and Level III, OA with discopexy. Several arthroscopic procedures, such as lysis of adherences, coblation of the retrodiscal tissue, anterior myotomy of the lateral pterigoid muscle, or discopexy, are classified in each category depending on the need (or not) to use of one or two working cannulas. CONCLUSION: Teaching and training of maxillofacial surgeons in the acquisition of the skills to perform arthroscopy should be based on a step-by-step approach following this proposed classification. Besides, future clinical series on arthroscopy of the TMJ for the treatment of ID and/or osteoarthrosis may benefit from a clear distinction of the performed arthroscopic procedure in terms of evaluating outcomes and complications.

4.
Polymers (Basel) ; 14(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36501619

RESUMO

Currently, demand for functional foods is increasing in the public interest in order to improve life expectations and general health. Food matrices containing probiotic microorganisms and active compounds encapsulated into carrier agents are essential in this context. Encapsulation via the lyophilisation method is widely used because oxidation reactions that affect physicochemical and nutritional food properties are usually avoided. Encapsulated functional ingredients, such as quercetin and Bacillus clausii, using two carrier agents' matrices-I [inulin (IN), lactose (L) and maltodextrin (MX)] and II [arabic (A), guar (G), and xanthan (X) gums)]-are presented in this work. A D-optimal procedure involving 59 experiments was designed to evaluate each matrix's yield, viability, and antioxidant activity (AA). Matrix I (33.3 IN:33.3 L:33.3 MX) and matrix II (33.3 A:33.3 G:33.3 X) exhibited the best yield; viability of 9.7 log10 CFU/g and 9.73 log10 CFU/g was found in matrix I (using a ratio of 33.3 IN:33.3 L:33.3 MX) and matrix II (50 G:50 X), respectively. Results for the antioxidant capacity of matrix I (100 IN:0 L:0M X) and matrix II (0 A:50 G:50 X) were 58.75 and 55.54 (DPPH* scavenging activity (10 µg/mL)), respectively. Synergy between matrices I and II with use of 100IN:0L:OMX and 0A:50G:50X resulted in 55.4 log10 CFU/g viability values; the antioxidant capacity was 9. 52 (DPPH* scavenging activity (10 µg/mL). The present work proposes use of a carrier agent mixture to produce a functional ingredient with antioxidant and probiotic properties that exceed the minimum viability, 6.0 log10 CFU/g, recommended by the FAO/WHO (2002) to be probiotic, and that contributes to the recommended daily quercetin intake of 10-16 mg/day or inulin intake of 10-20 g/day and dietary fibre intake of 25-38 g per day.

7.
Atlas Oral Maxillofac Surg Clin North Am ; 30(2): 185-191, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36116877

RESUMO

Arthroscopic rigid fixation (ARF) of the temporomandibular joint (TMJ) with resorbable pins and other advanced arthroscopic disc repositioning (ADR) techniques by sutures has provided a renewed interest in the role played by the disc in the treatment of the most severe cases of TMJ ID with anterior disc displacement with severe limitation of mouth opening. These techniques may be the last step prior to open TMJ surgery, if other less complex operative arthroscopic techniques (OAT) have previously failed, or for those cases in which no predictable results are expected with simpler OAT due to the presence of a severe displaced disc or closed lock. In this article, ARF with resorbable pins is being approached, with a special focus on describing the technique while reporting its advantages and disadvantages. Also, potential complications and postoperative management and recovery, together with some advice in terms of pearls and pitfalls will be exposed.


Assuntos
Luxações Articulares , Transtornos da Articulação Temporomandibular , Artroscopia/métodos , Humanos , Luxações Articulares/cirurgia , Articulação Temporomandibular , Disco da Articulação Temporomandibular/cirurgia , Transtornos da Articulação Temporomandibular/cirurgia
8.
Sci Rep ; 12(1): 9917, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35705682

RESUMO

This study evaluated the effectiveness of a biocoagulant produced from the devilfish invasive species and its combination with two chemical coagulants (aluminum sulfate and ferric sulfate) to remove turbidity, chemical oxygen demand, and total suspended solids in ceramic industry wastewater using a combined experimental design of Mixture-Process. This design optimized the coagulation process and evaluated the effects and interactions between mixture components and coagulant doses. An analysis of variance was used to analyze the experimental data obtained in the study, and the response surface plots by response type (turbidity, chemical oxygen demand, and total suspended solids) were obtained. Results showed that the coagulation treatment could be technically and economically feasible since efficiencies of turbidity, chemical oxygen demand, and total suspended solids removal of 74, 79, and 94% could be achieved using an optimal coagulant dose of 800 mg/L with a mixture of 35% biocoagulant and 65% ferric sulfate. Analysis of variance results showed that the models are significant, and the lack of fit is not required according to the probability value (p value), which were < 0.0001, and > 0.05, respectively. Hence, the experimental data were fitted to a combined reduced special cubic x linear model. These results support the use of devilfish meal as a biocoagulant, being more feasible in dual systems when mixed with ferric sulfate.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cerâmica , Floculação , Espécies Introduzidas , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos
10.
Drug Dev Ind Pharm ; 47(10): 1546-1555, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34791982

RESUMO

OBJECTIVE: The aim of this work was to characterize Lippia graveolens oleoresins, obtained by Supercritical Fluid Extraction (SFE), from crops collected at different locations in Mexico. The antimicrobial effect of oleoresins was tested in reference strains and clinical isolates of susceptible and multidrug-resistant (MDR) strains of Enterococcus faecalis and Staphylococcus aureus. SIGNIFICANCE: The increasing of MDR strains is becoming a global public health problem that has led to the search for new treatments, and essential oils have resurged as a source of compounds with bactericidal functions. Oregano essential oil has attracted attention recently, however, this oil is mainly obtained by hydro-distillation (uses large amounts of water) or solvents extraction (potential contaminant). SFE has gained popularity as it represents an environmentally friendly technology. METHODS: L. graveolens oleoresins were obtained by SFE, total phenol contents were quantified by Folin-Ciocalteu method, the identification of compounds and thymol and carvacrol quantification was carried out by GC-MS. The antimicrobial activity was tested by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). RESULTS: SFE showed higher yields compared with the hydro-distillation process. L. graveolens grown in different Mexican locations showed differences in oleoresin composition and a slightly different antimicrobial capacity against clinical isolates. CONCLUSIONS: It was demonstrated that SFE is an efficient technology for extracting L. graveolens oleoresins. Additionally, the solvent-free extraction method and the observed antimicrobial effect increase the applications of these oleoresins in fields, such as cosmetics, food industry, medicine, amongst others.


Assuntos
Anti-Infecciosos , Lippia , Óleos Voláteis , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Resistência a Múltiplos Medicamentos , Enterococcus faecalis , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Extratos Vegetais , Staphylococcus aureus
12.
J Tissue Eng Regen Med ; 15(10): 852-868, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34323386

RESUMO

The effort to develop an effective and safe temporomandibular joint (TMJ) disc substitute has been one of the mainstreams of tissue engineering. Biodegradable customized scaffolds could approach safety and effectiveness to regenerate a new autologous disc, rather than using non-biodegradable materials. However, it is still technically challenging to mimic the biomechanical properties of the native disc with biodegradable polymers. In this study, new 3D tailored TMJ disc implants were developed: (1) Poly(glycerol sebacate) (PGS) scaffold reinforced with electrospun Poly(εcaprolactone) (PCL) fibers on the outer surface (PGS+PCL); (2) PCL and polyethylene glycol diacrylate (PEGDA) (PCL+PEGDA); and (3) PCL. The TMJ implants were tested in a randomized preclinical trial, conducted in 24 black Merino sheep TMJ, perfoming bilateral interventions. Histologic, imaging, and kinematics analysis was performed. No statistical changes were observed between the PGS+PCL disc and the control group. The PCL+PEGDA and PCL groups were associated with statistical changes in histology (p = 0.004 for articular cartilage mid-layer; p = 0.019 for structure changes and p = 0.017 for cell shape changes), imaging (p = 0.027 for global appreciation) and dangerous material fragmentation was observed. No biomaterial particles were observed in the multi-organ analysis in the different groups. The sheep confirmed to be a relevant animal model for TMJ disc surgery and regenerative approaches. The PCL and PCL+PEGDA discs presented a higher risk to increase degenerative changes, due to material fragmentation. None of the tested discs regenerate a new autologous disc, however, PGS+PCL was safe, demonstrated rapid resorption, and was capable to prevent condyle degenerative changes.


Assuntos
Implantes Experimentais , Disco da Articulação Temporomandibular/cirurgia , Animais , Fenômenos Biomecânicos , Peso Corporal , Decanoatos/química , Glicerol/análogos & derivados , Glicerol/química , Especificidade de Órgãos , Poliésteres/química , Polímeros/química , Ovinos , Disco da Articulação Temporomandibular/diagnóstico por imagem , Disco da Articulação Temporomandibular/fisiologia , Tomografia Computadorizada por Raios X
13.
Int J Biol Macromol ; 183: 2293-2304, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34097967

RESUMO

In this work, the synthesis of crosslinked chitosan hydrogels was performed by ionic and covalent interactions using tripolyphosphate (TPP) and formaldehyde (CH2O), respectively. The hydrogels synthesis was performed using a D-Optimal combined experiment design with two mixing variables, A and B representing the TPP weight fraction (slack variable) and CH2O weight fraction, respectively, and three (3) process variables C-chitosan concentration, D-cross-linker concentration, and E-Contact time. The response variables studied were the point of zero charge (pHPZC), the swelling ratio (SW), and the equilibrium water content (EWC), which are relevant physicochemical properties in applications such as the pollutant removal from water. According to the ANOVA results, the model obtained was significant; this means it can be adequately used to predicting pHPZC, SW, and EWC from the mixing and process variables, obtaining coefficients of determination R2 of 0.9572, 0.8900, and 0.8447, respectively. The pHPZC is affected by chitosan concentration, while the crosslinker concentration influences the SW, and the contact time most significantly affected the EWC. Morphology and hardness tests, thermal stability, infrared spectroscopy, and scanning electron microscopy, allowed verifying the types of crosslinking of chitosan with TPP and CH2O.


Assuntos
Quitosana/química , Reagentes de Ligações Cruzadas/química , Formaldeído/química , Polifosfatos/química , Dureza , Hidrogéis , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Propriedades de Superfície , Temperatura , Fatores de Tempo
14.
J Food Sci ; 86(5): 1946-1962, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33844286

RESUMO

Specific heat capacity ( C P ) is regarded as a fundamental parameter for the design, operation, and optimization of the heat transfer equipment widely used in the food industry. Using the calorimetric ASTM E1269-11 standard procedure, the C P -temperature ( C P ( T ) ) curves of fruit juice model systems prepared at different mass fractions of fructose/glucose/sucrose/citric acid/pectin and water were measured. Thus, experimental data of C P for solid samples in crystalline and amorphous states from -80 °C up to the melting temperature range and for aqueous samples from -80 to 110 °C were generated. In the tested temperature interval, the C P of crystalline, amorphous, and aqueous samples were found to be in the ranges of 0.037 ± 0.020 to 5.61 ± 0.04; 0.061 ± 0.004 to 3.12 ± 0.19, and 0.363 ± 0.05 to 3.24 ± 0.14 kJ/kg °C, respectively. Also, a generalized empirical equation based on the type and concentration of components was developed to predict the C P ( T ) curves of the studied samples. The proposed equation exhibited a low error sum of squares (SSE <  57.3) and a high coefficient of determination (R2 > 0.927). An analysis of variance (ANOVA) was performed with a confidence level of 95% (p < 0.05). The C P ( T ) curves were influenced by temperature, thermal transitions, water, solid types, and compound interactions. Glucose was one of the solids that most significantly influenced the C P values of samples. PRACTICAL APPLICATION: The experimental specific heat capacity data and empirical equation proposed in this study are relevant to the design, evaluation, and optimization of heat transfer equipment involved in many foods and biochemical industrial processes such as cryopreservation, frozen storage, freezing, chilling, drying, and the cooking of hard candies.


Assuntos
Varredura Diferencial de Calorimetria/métodos , Frutose/química , Sucos de Frutas e Vegetais/análise , Glucose/química , Temperatura Alta , Sacarose/química , Água/química , Temperatura
15.
Rev. cienc. med. Pinar Rio ; 24(6): e4480, nov.-dic. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1156278

RESUMO

RESUMEN Introducción: la distrofia miotónica de Steinert. Es una enfermedad heredo familiar con patrón de transmisión autosómico dominante. Objetivo: describir familias con distrofia miotónica de Steinert pesquisadas en la Atención Primaria de Salud. Presentación de familias: se trata de una muestra de 126 miembros pertenecientes a dos familias, residentes en la provincia Pinar del Río, Cuba, en la que varios de sus miembros tenían diagnosticada la enfermedad. Se realizó un pesquisaje durante el año 2019, y entre enero y marzo del 2020, a cada miembro de ambas familias, se les completó las genealogías y evaluaron las características clínicas. Se trabajó con algunas variables relacionadas con las formas clínicas de la enfermedad según las generaciones. Resultados: se presentaron mediante el árbol genealógico dos familias, con 40 y 86 miembros, de los municipios de Minas de Matahambre y Pinar del Río respectivamente. En el primer municipio se registraron nueve personas con la forma leve y clásica de la enfermedad, de estas más de la mitad no conocían su condición, 21 personas eran aparentemente sintomáticas. En el segundo municipio, 21 casos fueron evaluados con alguna forma clínica de la enfermedad, que con respecto al total de casos pesquisados representaron el 26,5 %. Conclusiones: es esencial la pesquisa a las familias con distrofia miotónica de Steinert, ya que existe una disociación de los signos clínicos y expresión variable de la enfermedad. Es la Atención Primaria de Salud el escenario que permite el diagnóstico precoz y manejo multidisciplinario.


ABSTRACT Introduction: the dystrophy miotónica of Steinert. It is an illness I inherit family with pattern of transmission dominant autosómico. Objective: to describe families with Steinert´s Myotonic Dystrophy, surveyed in Primary Health Care. Report of families: it is about a sample of 126 members belonging to two families, in which several of their members had been diagnosed with the entity; both families are from Pinar del Río province, Cuba. A survey was conducted during 2019, and between January and March 2020, each member of both families had their genealogies completed and their clinical characteristics evaluated; working with some variables related to the clinical types of this entity according to the generations. Results: two families were presented through the genealogical tree, with 40 and 86 members from the municipalities of Minas de Matahambre and Pinar del Río municipalities respectively. In the first municipality, nine persons (9) were registered with the mild and classic type of the disease, of these more than 50 % did not know their condition, and 21 persons were apparently symptomatic. In the second municipality, 21 cases were evaluated some clinical characteristics of the disease, which with respect to the total number of cases surveyed represented 26,5 %. Conclusions: it is essential to study families with Steinert's Myotonic Dystrophy, since there is a dissociation of clinical signs and variable expression of the disease. It is the Primary Health Care the setting which allows early diagnosis and multidisciplinary management of this disease.

16.
Polymers (Basel) ; 12(9)2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32932726

RESUMO

The state diagram, which is defined as a stability map of different states and phases of a food as a function of the solid content and temperature, is regarded as fundamental approach in the design and optimization of processes or storage procedures of food in the low-, intermediate-, and high-moisture domains. Therefore, in this study, the effects of maltodextrin addition on the freezing points (Tm', Tm) and glass transition temperatures (Tg', Tg) required for the construction of state diagrams of fruit juice model systems by using differential scanning calorimetry methods was investigated. A D-optimal experimental design was used to prepare a total of 25 anhydrous model food systems at various dry mass fractions of fructose, glucose, sucrose, pectin, citric acid, and maltodextrin, in which this last component varied between 0 and 0.8. It was found that maltodextrin mass fractions higher than 0.4 are required to induce significant increases of Tg', Tm', Tg, and Tm curves. From this perspective, maltodextrin is a good alternative as a cryoprotectant and as a carrier agent in the food industry. Furthermore, solute-composition-based mathematical models were developed to evaluate the influence of the chemical composition on the thermal transitions and to predict the state diagrams of fruit juices at different maltodextrin mass fractions.

18.
Rev. esp. cir. oral maxilofac ; 42(3): 97-106, jul.-sept. 2020. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-196625

RESUMO

INTRODUCCIÓN: Los trastornos internos (TI) de la articulación temporomandibular (ATM) constituyen la condición clínica articular más frecuente en pacientes con trastornos temporomandibulares (TTM). Presentes hasta en un 80-90 % de los casos sintomáticos, no se sabe por qué, su presencia en sujetos asintomáticos no causa dolor ni disfunción. En contraposición, una posición normal del disco ha sido descrita en un 16-23 % de pacientes sintomáticos. OBJETIVOS: Analizar la prevalencia de TI de la ATM en sujetos voluntarios asintomáticos y qué características clínico-radiológicas podrían favorecer su presencia o desarrollo. MATERIAL Y MÉTODO: Se diseñó un estudio descriptivo, observacional, transversal. Se seleccionaron 43 sujetos de una población de 253 residentes que realizaban su formación médica especializada. El estudio fue desarrollado en varias fases. Fase I: Anamnesis y examen clínico. Empleo del índice craneomandibular de Fricton (ICM); Fase II: Adquisición y evaluación de imágenes de Resonancia Magnética (RMN). Las imágenes fueron procesadas a formato DICOM 4.0 y evaluadas por dos examinadores externos. Fase III: Análisis morfoestructural de las ATM. Las imágenes de RMN fueron analizadas empleando el programa informático Osirix® V 3.5.1. RESULTADOS: Setenta y dos articulaciones (pertenecientes a 36 sujetos) fueron finalmente analizadas. La edad media fue de 28,39 ± 3,70 años con una distribución por sexos de 47,2 % hombres y de 52,8 % mujeres. El análisis inferencial mostró resultados estadísticamente significativos en relación con las variables sexo (p = 0,021), chasquido articular (p = 0,007), valor del ICM (p = 0,000296), morfología discal (p = 1,032 X 10-8), morfología condilar (p = 2,116 X 10-8), posición condilar en el interior de la ATM (longitudes posterior y superior, p = 5,385 X 10-9; p = 0,000245, respectivamente) y morfología de la fosa articular (p = 0,024). CONCLUSIONES: Existe una elevada prevalencia de TI de la ATM en los sujetos asintomáticos analizados. Ciertos criterios clínicos (chasquido articular) y radiológicos (morfología discal alargada/doblada, cóndilo y fosa aplanados y posición más posterior y craneal del cóndilo mandibular) podrían ser considerados como predictores o relacionados con la presencia de desplazamiento discal. El ICM podría constituir una herramienta útil en el diagnóstico de patología articular de la ATM


INTRODUCTION: Internal derangements (IDs) of the temporomandibular joint (TMJ) constitute the most common clinical joint condition in patients with temporomandibular disorders (TMDs). Present in up to 80-90 % of symptomatic cases, it is not known why, its presence in asymptomatic subjects does not cause pain or dysfunction. In contrast, a normal position of the disc has been described in 16-23 % of symptomatic patients. OBJECTIVES: To analyze the prevalence of IDs of the TMJ in asymptomatic voluntary subjects and what clinical-radiological characteristics could favor their presence or development. MATERIAL AND METHODS: A descriptive, observational, cross-sectional study was designed. Fortythree subjects from a population of 253 residents who performed their training program were selected. The study was carried out in several phases. Phase I: Anamnesis and clinical examination. Use of the Fricton Cranio-mandibular Index (CMI); Phase II: Acquisition and evaluation of Magnetic Resonance Imaging (MRI). The images were processed in DICOM 4.0 format and evaluated by two external examiners. Phase III: Morpho-structural analysis of the TMJs. The MRI were analyzed using the Osirix® V 3.5.1 Software. RESULTS: Seventy-two joints (belonging to 36 subjects) were finally analyzed. The mean age was 28.39 ± 3.70 years with a distribution by sex of 47.2% men and 52.8 % women. The inferential analysis showed statistically significant results in relation to the variables sex (p = 0.021), joint click (p = 0.007), CMI value (p = 0.000296), disc morphology (p = 1.032x10-8), condylar morphology (p = 2.116x10-8) and condylar position inside the TMJ ((posterior and superior lengths, p = 5.385x10-9; p = 0.000245, respectively) and morphology of the joint fossa (p = 0.024). CONCLUSIONS: A high prevalence of IDs in asymptomatic subjects is present in our study. Certain clinical (joint clicking) and radiological criteria (an elongated or bent disc morphology, a flattened condyle and fossa and a more posterior and cranial position of the mandibular condyle) could be considered as predictors or be related to the presence of disc displacement. The CMI could be a useful tool in the diagnosis of joint pathology of the TMJ


Assuntos
Humanos , Masculino , Feminino , Adulto , Transtornos da Articulação Temporomandibular/epidemiologia , Disco da Articulação Temporomandibular/fisiopatologia , Doenças Assintomáticas/epidemiologia , Transtornos da Articulação Temporomandibular/diagnóstico , Voluntários Saudáveis/classificação , Estudos Transversais
20.
J Phys Chem B ; 124(21): 4338-4357, 2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32352290

RESUMO

The use of ionic liquids (ILs) as both catalysts and solvents in a wide range of chemical reactions has received considerable attention over the last few years due to their positive effects in enhancing reaction rates and selectivities. In this work, hybrid quantum mechanics/molecular mechanics (QM/MM) molecular dynamics simulations were carried out in conjunction with umbrella-sampling techniques to study the bimolecular nucleophilic substitution (SN2) fluorination reaction between propyl-mesylate and potassium fluoride using five ILs as solvents, specifically, 1-butyl-3-methylimidazolium mesylate ([C4mim][OMs]), 1-butyl-3-methylimidazolium tetrafluoroborate ([C4mim][BF4]), 1-butyl-3-methylimidazolium trifluoroacetate ([C4mim][CF3COO]), 1-butyl-3-methylimidazolium bromide ([C4mim][Br]), and 1-butyl-3-methylimidazolium chloride ([C4mim][Cl]) at 373.15 K. The QM region (reactive part) in all QM/MM systems was simulated using the Parametric Method 6 (PM6) semiempirical methods, and for the MM region (IL solvent), classical force fields (FF) were employed, with the FF developed within the group. The calculated activation free energy barriers (ΔG‡) for the SN2 reaction in the presence of [C4mim][OMs] and [C4mim][BF4] ILs were in agreement with the experimental values reported in the literature. On the other hand, only predicted values were obtained for the activation energies for the [C4mim][CF3COO], [C4mim][Br], and [C4mim][Cl] ILs. These activation energies indicated that the SN2 reaction would be more facile to proceed using the [C4mim][Cl] and [C4mim][OMs] ILs, in contrast with the use of [C4mim][Br] IL, which presented the highest activation energy. Energy-pair distributions, radial distribution functions, and noncovalent interactions (NCI) were also calculated to elucidate the molecular interactions between the reactive QM region and the solvents or reaction media. From these calculations, it was found that not only the reactivity can be enhanced by selecting a specific anion to increase the K-F separation but also the cation plays a relevant role, producing a synergetic effect by forming hydrogen bonds with the fluorine atom from KF and with the oxygen atoms within the mesylate leaving group. Three interactions are significant for the IL catalytic behavior, FQM-HX, KQM-anion, and OQM-HX interactions, where the FQM and KQM labels correspond to fluorine and potassium atoms from the KF salt, OQM corresponds to oxygen atoms within the mesylate leaving group (reactant), and HX refers to hydrogen atoms within the IL cation. The NCI analysis revealed that KQM-anion interactions are of weak type, indicating the importance of hydrogen bond interactions from the cation such as FQM-HX and OQM-HX for the catalytic behavior of ILs.

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