RESUMEN

Introduction: While the relationship between narcissism and empathy has been well-researched, studies have paid less attention to empathic accuracy, i.e., appreciating the precise strength of another person's emotions, and self-other distinction, in terms of the disparity between affective ratings for self and other in response to emotive stimuli. Furthermore, empathic responses may vary depending on whether the pain is physical or social. Methods: We investigated empathic accuracy, affective empathy, and the distinction between pain, emotion and intensity ratings for self and other, in high (n = 44) and low (n = 43) narcissism groups (HNG and LNG, respectively) selected from 611 students, in response to both types of pain. Participants watched six videos where targets expressed genuine experiences of physical and social pain, and rated the perceived affect and pain experienced by the person in the video and their own empathic emotional responses. Results and discussion: The HNG displayed lower affective empathy and empathic accuracy than the LNG for both pain types. Within the HNG there was higher empathic accuracy for social vs. physical pain, despite reduced affective empathy for social pain, in contrast to the LNG. In addition to this paradox, the HNG demonstrated greater differences between ratings for the self and for target others than the LNG, suggesting that narcissism is associated with higher self-other distinction in response to viewing other people describing social pain.

RESUMEN

Heavy metal ions, i.e., copper(II) (Cu(II)), are harmful to the environment and our health. The current research established an eco-friendly and efficient metal-sensitive indicator, which can identify Cu(II) ions in both liquid and solid forms, by utilizing anthocyanin extract obtained from jambolao fruit (Syzgium cumini) that is incorporated within bacterial cellulose nanofibers (BCNF).The CIE Lab color parameters demonstrated that Cu(II) binding causes a sensible change in color. It was observed that the visible color altered with an increase in the Cu(II) concentration. The bacterial cellulose nanofibers that were altered with anthocyanin were analyzed using ATR-FTIR and FESEM. The sensor's selectivity was tested by using a range of metal ions such as lead (Pb2+), cobalt (Co2+), cadmium (Cd2+), nickel (Ni2+), aluminium (Al3+), barium (Ba2+), manganese (Mn2+), zinc (Zn2+), mercury (Hg2+) and sodium (Na+). The findings demonstrated that the suggested sensor showed excellent selectivity toward Cu(II) ion. Cu(II) can be accurately identified using the sensing technique, with detection limits ranging from 10-400 ppm and 50-500 ppm for liquid and solid samples, respectively, and through observation with naked eye. The fabricated green metallochromic sensor is promising to be a simple, cheap, mobile and easily operable for the real-time and on-site detection of Cu(II) ion.

RESUMEN

An intelligent pH-sensing indicator containing Roselle (Hibiseus sabdariffa L.) (RS) anthocyanin and curcumin (CR) was developed and characterized as on-package indicator tags to check the freshness of shrimp during the storage at 4°C. FE-SEM and FT-IR analysis showed that RS and CR were successfully immobilized in the gelatin-glycerol film-forming substrate. The addition of various natural dyes increased the thickness and antioxidant action of the colorimetric film. To assess the response to changes in the pH, the colorimetric film was immersed in different buffers. Based on volatile amines secreted by shrimp, a test application of a colorimetric film containing natural dyes at a ratio of CR:RS = 1:4 (v/v) was conducted in shrimp at 4°C. The total volatile basic nitrogen (TVB-N) and the pH of shrimp were monitored during refrigerated storage for 10 days, and the color changes of the indicator were recorded simultaneously. The results indicated that the designed colorimetric film could produce various colors, which are thought to be indicative of the freshness and spoilage of packaged shrimp. Therefore, the target film can be utilized as a promising smart packaging material for monitoring the freshness of shrimp and aquatic products in real time.

RESUMEN

The environment and our health are negatively impacted by heavy metal ions, like Cu(II). The present study developed a green and effective metallochromic sensor that detects copper (Cu(II)) ions in solution and solid state using anthocyanin extract from black eggplant peels embedded in bacterial cellulose nanofibers (BCNF). Cu(II) is quantitatively detected by the sensing method with detection limits between 10-400 ppm and 20-300 ppm in solution and solid state, respectively. In the solution state, we depicted a sensor for Cu(II) ions in aqueous matrices in the pH range from 3.0 to 11.0, with the capability to produce a visual color change from brown to light blue and dark blue depending on the Cu(II) concentration. Additionally, BCNF-ANT film can act as a sensor for Cu(II) ions in the pH range of 4.0-8.0. Neutral pH was selected from the standpoint of high selectivity. It was found that visible color changed when Cu(II) concentration was increased. Bacterial cellulose nanofibers modified with anthocyanin were characterized with ATR-FTIR and FESEM. Various metal ions, including Pb2+, Co2+, Zn2+, Ni2+, Al3+, Ba2+, Hg2+, Mg2+, and Na+, were used to challenge the sensor to determine its selectivity. Anthocyanin solution and BCNF-ANT sheet were employed in the actual tap water sample successfully. The results also clarified that the various foreign ions did not significantly interfere with Cu(II) ions detection at optimum conditions. Compared to previously developed sensors, no electronic components, trained personnel, or sophisticated equipment were needed to apply the colorimetric sensor developed in this research. Cu(II) contamination in food matrices and water can be monitored on-site easily.

Asunto(s)

Metales Pesados , Nanofibras , Celulosa/química , Antocianinas , Nanofibras/química , Cobre , Agua/química , Iones/química

RESUMEN

Seafood products as a source of vitamins, minerals, and polyunsaturated fatty acids represent an important component of the human diet. However, they are susceptible to spoilage even under appropriate storage conditions, making it indispensable to develop freshness indicators. In this study, we introduce a green user-friendly pH indicator film for the naked-eye monitoring of fish spoilage. The pH indicator was prepared by successful loading of a mixture of anthocyanin and curcumin on bacterial cellulose (BC) nanofiber substrate. BC nanofiber with the advantages of biocompatibility, biodegradability, high purity, and superior mechanical strength was promising for generating pH-sensing arrays. The Fourier transform infrared (FT-IR) analysis proved the incorporation of anthocyanin and curcumin into the BC skeleton. Besides, the scanning electron microscopy (SEM) results clarified the morphology of the modified film by anthocyanin and curcumin. The pH indicator film was still stable after preserving for 60 days at different temperatures. The curcumin-anthocyanin loaded nanofiber indicated a distinct color change after spoilage by its exposure to fish meat in a transparent plastic package. Hence, the modified film by the anthocyanin-curcumin mixture is potent for the naked-eye monitoring of meat spoilage.

Asunto(s)

Curcumina , Nanofibras , Animales , Humanos , Embalaje de Alimentos/métodos , Celulosa , Antocianinas , Polifenoles , Espectroscopía Infrarroja por Transformada de Fourier , Concentración de Iones de Hidrógeno

RESUMEN

Copper(II)/polyimide-linked covalent organic frameworks under solvent-free and microwave-assisted conditions have been used in an efficient one-pot protocol for the preparation of 2,4,5-trisubstituted imidazoles via benzil, aromatic aldehydes and ammonium acetate. By applying solvent-free conditions and microwave irradiation, three-component condensation provides safe operations, low pollution, quick access to products, and an easy set-up. As a result of its reusability, the catalyst can also be reutilized for many runs without missing any activity.

RESUMEN

The present study developed a green metallochromic sensor that detects aluminium (Al(III)) ions in solution and solid state using anthocyanin extract from purple onion peels embedded in bacterial cellulose nanofibers (BCNFs). The CIE Lab colour parameters demonstrated that Al(III) binding causes a sensible change in colour. A variety of metal ions including K+, Mn2+, Cu2+, Hg2+, Cr2+, Pb2+ and Ni2+ were used to challenge the sensor to determine its selectivity. The findings demonstrated that the suggested sensor showed excellent selectivity toward Al(III) ion. Al(III) is quantitatively detected by the sensing method with detection limits in the range between 30-200 and 20-300 ppm in solution and solid state, respectively, and through observation with naked eye. The fabricated green metallochromic sensor is promising to be a simple, cheap, mobile and easily operable for real-time and on-site detection of Al(III) ions in food matrices.

RESUMEN

Pseudomonas aeruginosa is an important nosocomial pathogen with a capacity of resistance to multiple antibiotics and production of various extracellular and cell-associated virulence factors that clearly contribute to its pathogenicity. The objective of this study was to investigate the antibiotic susceptibility, virulence factors, and clonal relationship among clinical isolates of P. aeruginosa. Different clinical specimens from hospitalized patients were investigated for P. aeruginosa. Susceptibility of the isolates was evaluated by disc diffusion and broth microdilution methods, as described by the Clinical and Laboratory Standards Institute (CLSI) guideline. A total of 97 P. aeruginosa isolates were recovered from clinical specimens. The percentage of isolates resistant to antimicrobials was imipenem 25.77%, meropenem 15.46%, gentamicin 16.49%, tobramycin 15.46%, amikacin 16.49%, ciprofloxacin 20.61%, levofloxacin 24.74, ceftazidime 20.61%, piperacillin 15.46%, piperacillin/tazobactam 12.37%, colistin 9.27%, and polymyxin B 11.34%. Of isolates, 87.62% possessed β-hemolytic activity, 78.35% lecithinase, 59.8% elastase, 37.11% DNase, and 28.86% twitching motility. The frequency of virulence genes in isolates was lasB 82.47%, plcH 82.47%, exoA 58.76%, exoS 56.7%, and pilA 10.3%. ERIC-PCR typing clustered P. aeruginosa isolates to 19 common types (CT1-CT19) containing isolates from different hospitals and 43 single types (ST1-ST43). Colistin and polymyxin B were the most effective agents against the majority of P. aeruginosa isolates, emphasizing the effort to maintain their antibacterial activity as last-line therapy. The frequency of some virulence factors and genes was noticeably high, which is alarming. In addition, more effective strategies and surveillance are necessary to confine and prevent the inter-hospital and/or intra-hospital dissemination of P. aeruginosa between therapeutic centers.(AU)

Asunto(s)

Humanos , Virulencia , Factores de Virulencia , Farmacorresistencia Microbiana , Pseudomonas aeruginosa , Microbiología , Irán , Investigación

RESUMEN

The liquid crystal (LC) detection platform has been fabricated for the detection of hypochlorite ions (ClO-) in aquatic solutions. In this system, an imine consisting of the ligand (E)-2-((4-(diethylamino)-2-hydroxybenzylidene)amino)-5-methoxybenzenesulfonic acid (MBA) was doped in 4-cyano-4'-pentyl biphenyl as a selecting LC for ClO-. When immersing the platform in a solution containing ClO-, hypochlorite appears to react with the imine bond in the MBA, and cause it to cleave, which eventually disrupts the direction of LC and causes a dark-to-bright conversion of the LC image. The detection limit for ClO- is 0.05 µM. This sensory platform was unresponsive to NO3 -, BrO3 -, CH3COO-, CO3 2-, and PO4 3- ions. Our sensing platform also detected ClO- in piped water. Since this sensory platform is colored under ambient light, it is easy for regular operators, and it can be used as a mobile tool for monitoring water quality anywhere.

RESUMEN

Pseudomonas aeruginosa is an important nosocomial pathogen with a capacity of resistance to multiple antibiotics and production of various extracellular and cell-associated virulence factors that clearly contribute to its pathogenicity. The objective of this study was to investigate the antibiotic susceptibility, virulence factors, and clonal relationship among clinical isolates of P. aeruginosa. Different clinical specimens from hospitalized patients were investigated for P. aeruginosa. Susceptibility of the isolates was evaluated by disc diffusion and broth microdilution methods, as described by the Clinical and Laboratory Standards Institute (CLSI) guideline. A total of 97 P. aeruginosa isolates were recovered from clinical specimens. The percentage of isolates resistant to antimicrobials was imipenem 25.77%, meropenem 15.46%, gentamicin 16.49%, tobramycin 15.46%, amikacin 16.49%, ciprofloxacin 20.61%, levofloxacin 24.74, ceftazidime 20.61%, piperacillin 15.46%, piperacillin/tazobactam 12.37%, colistin 9.27%, and polymyxin B 11.34%. Of isolates, 87.62% possessed ß-hemolytic activity, 78.35% lecithinase, 59.8% elastase, 37.11% DNase, and 28.86% twitching motility. The frequency of virulence genes in isolates was lasB 82.47%, plcH 82.47%, exoA 58.76%, exoS 56.7%, and pilA 10.3%. ERIC-PCR typing clustered P. aeruginosa isolates to 19 common types (CT1-CT19) containing isolates from different hospitals and 43 single types (ST1-ST43). Colistin and polymyxin B were the most effective agents against the majority of P. aeruginosa isolates, emphasizing the effort to maintain their antibacterial activity as last-line therapy. The frequency of some virulence factors and genes was noticeably high, which is alarming. In addition, more effective strategies and surveillance are necessary to confine and prevent the inter-hospital and/or intra-hospital dissemination of P. aeruginosa between therapeutic centers.

Asunto(s)

Infecciones por Pseudomonas , Pseudomonas aeruginosa , Amicacina/farmacología , Amicacina/uso terapéutico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Ceftazidima/farmacología , Ceftazidima/uso terapéutico , Ciprofloxacina/farmacología , Ciprofloxacina/uso terapéutico , Colistina/farmacología , Desoxirribonucleasas/genética , Desoxirribonucleasas/farmacología , Desoxirribonucleasas/uso terapéutico , Farmacorresistencia Bacteriana/genética , Genotipo , Gentamicinas/farmacología , Gentamicinas/uso terapéutico , Humanos , Imipenem/farmacología , Imipenem/uso terapéutico , Irán , Levofloxacino/farmacología , Levofloxacino/uso terapéutico , Meropenem/farmacología , Meropenem/uso terapéutico , Pruebas de Sensibilidad Microbiana , Elastasa Pancreática/genética , Elastasa Pancreática/farmacología , Elastasa Pancreática/uso terapéutico , Fosfolipasas/genética , Fosfolipasas/farmacología , Fosfolipasas/uso terapéutico , Piperacilina/farmacología , Piperacilina/uso terapéutico , Combinación Piperacilina y Tazobactam/farmacología , Combinación Piperacilina y Tazobactam/uso terapéutico , Polimixina B/farmacología , Infecciones por Pseudomonas/microbiología , Tobramicina/farmacología , Tobramicina/uso terapéutico , Factores de Virulencia/genética

RESUMEN

Quinoline yellow (QY) is one of the popular synthetic food colorants and in food industry greatly used. Developing accurate and simple QY detection procedures is of major considerable importance in ensuring food safety. Hence, it is important to detect this food colorant effectively to reduce risk. Herein, an innovative liquid crystal (LC)-based sensor was designed for the label-free and ultra-sensitive detecting of the QY by means of a cationic surfactant-decorated LC interface. The nematic liquid crystal in touch with CTAB revealed a homeotropic alignment, when QY was injected into the LC-cell, the homeotropic alignment consequently altered to a planar one by electrostatic interactions between QY and CTAB. The designed LC-based sensor detected QY at the too much trace level as low as 0.5 fM with analogous selectivity. The suggested LC-based sensor is a rapid, convenient and simple procedure for label-free detection of QY in food industrial and safety control application.

RESUMEN

In this study, a Schiff base derived from a heterocyclic moiety was synthesized and characterized. The in vitro binding behaviour of this ligand with ß-casein (ß-CN) was investigated using biophysical techniques. For evaluation, thermodynamics variables of interactions between the Schiff base ligand and ß-CN, such as fluorescence at different temperatures, were measured. The results showed that the Schiff base ligand possessed considerable associated binding to ß-CN and that the procedure was enthalpy driven. The ß-CN conformation was also changed to give a further unfolded structure. Fluorescence resonance energy transfer was used to estimate the interval between donor (ß-CN) and acceptor (Schiff base ligand). All these experimental results proposed that ß-CN might act as carrier protein for the Schiff base ligand to deliver it to the target molecules.

Asunto(s)

Caseínas , Bases de Schiff , Animales , Sitios de Unión , Caseínas/metabolismo , Bovinos , Dicroismo Circular , Ligandos , Unión Proteica , Albúmina Sérica Bovina/metabolismo , Espectrometría de Fluorescencia , Termodinámica

RESUMEN

In this study, two metal Schiff base complexes (cobalt(II) and manganese(II), were synthesized and characterized by 1H-NMR and FT-IR analyses. The in vitro binding behavior of this complexes with ß-Casein (ß-CN) was investigated by using biophysical techniques. For evaluation the thermodynamics parameters of interaction between Schiff base complexes and ß-CN,the fluorescence data at different temperatures were done. The results showed that the intrinsic fluorescence of the ß-CN was quenched by increasing the complexes through the dynamic quenching mechanism. Also, these complexes demonstrated a considrable binding affinity to ß-CN and the process is mainly entropy driven. Fluorescence resonance energy transfer was used in order to estimating the distance between donor (ß-CN) and acceptor (complex). Results demonstrated that the sequence of tendency of the complexes to ß-CN was as follows: Mn-Schiff base complex > Co-Schiff base complex. All these experimental results propose that ß-CN might act as carrier protein for Co(II) and Mn (II) complexes to deliver it to the target molecules.

Asunto(s)

Caseínas/química , Cobalto/química , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Manganeso/química , Técnicas de Química Sintética , Transferencia Resonante de Energía de Fluorescencia , Bases de Schiff/química

RESUMEN

The interaction of pepsin with sunset yellow food additive (SY) was studied by fluorescence spectroscopy and molecular dynamics simulation. The experimental results indicated that SY can quench the fluorescence of pepsin with static quenching. The apparent binding constant Ka and binding site number n were evaluated at different temperatures. Thermodynamic analysis suggests that SY interact with pepsin spontaneously by van der Waal's forces and hydrogen bond formation. Three-dimensional fluorescence spectra showed that pepsin undergoes a slightly conformation change when it interacts with SY. The molecular dynamics simulation (MD) revealed that the binding site is located mainly on the tyrosine residues at the entrance of the active site of pepsin and the main interactions occurred between SY and pepsin are hydrogen bond and stacking interactions, according to experimental results. Furthermore, the binding between SY and pepsin can inhibit pepsin activity. Our MD results showed that the SY prevents substrate from entering the active site by making a barrier at the entrance of the active site, reducing the pepsin activity.

Asunto(s)

Compuestos Azo/metabolismo , Aditivos Alimentarios/metabolismo , Simulación de Dinámica Molecular , Pepsina A/metabolismo , Pepsina A/química , Unión Proteica , Conformación Proteica , Análisis Espectral

RESUMEN

ß-Lactoglobulin (ß-LG), the major whey protein in milks of many mammals, has a high affinity for a wide range of compounds. Cyclosporine A (CsA), is an immunosuppressant drug mainly prescribe in organ transplantation to prevent rejection. In this study, the interaction of CsA with ß-LG was investigated using various spectroscopic techniques (UV-visible and fluorescence) in an aqueous medium at two temperatures of 298 and 310K in combination with a molecular dynamics simulation study. The titration results indicated that CsA quenched the fluorescence intensity of ß-LG through a static mechanism. The binding constants for the binding of CsA to ß-LG at two different temperatures 298 and 310K were obtained 1.12×105 and 0.87×105M-1, respectively. Thermodynamic data indicated that the hydrophobic interactions and hydrogen bonds dominate in the binding site. Results of fluorescence resonance energy transfer (FRET) measurements suggest that resonance energy transfer occurs between ß-LG and CsA. Moreover, MD simulation results implied that CsA can interact with ß-LG, without affecting the secondary structure of ß-LG. Experimental and MD simulations data reciprocally supported each other.

Asunto(s)

Ciclosporina/metabolismo , Lactoglobulinas/metabolismo , Simulación de Dinámica Molecular , Sitios de Unión , Lactoglobulinas/química , Unión Proteica , Estructura Secundaria de Proteína , Análisis Espectral , Termodinámica

RESUMEN

The interaction between losartan and human serum albumin (HSA), as well as its glycated form (gHSA) was studied by multiple spectroscopic techniques and molecular dynamics simulation under physiological conditions. The binding information, including the binding constants, effective quenching constant and number of binding sites showed that the binding partiality of losartan to HSA was higher than to gHSA. The findings of three-dimensional fluorescence spectra demonstrated that the binding of losartan to HSA and gHSA would alter the protein conformation. The distances between Trp residue and the binding sites of the drug were evaluated on the basis of the Förster theory, and it was indicated that non-radiative energy transfer from HSA and gHSA to the losartan happened with a high possibility. According to molecular dynamics simulation, the protein secondary and tertiary structure changes were compared in HSA and gHSA for clarifying the obtained results.

Asunto(s)

Losartán/metabolismo , Albúmina Sérica/metabolismo , Sitios de Unión , Transferencia de Energía , Productos Finales de Glicación Avanzada , Humanos , Losartán/química , Simulación de Dinámica Molecular , Unión Proteica , Conformación Proteica , Albúmina Sérica/química , Espectrometría de Fluorescencia/métodos , Albúmina Sérica Glicada