Comparative Study of the Antioxidant Activity of the Conformers of C-tetra(4-methoxyphenyl)calix[4]resorcinarene.

C-tetra(4-methoxyphenyl)calix[4]resorcinarene was synthesized by hydrochloric acid-catalysed cyclocondensation of resorcinol and 4-methoxybenzaldehyde. Under these conditions, the reaction produces a conformational mixture of crown and chair structural conformers, which were separated and characterized by chromatographic and spectroscopic techniques. The antioxidant activity of both conformers was measured by using the DPPH assay, through which it was observed that the chair conformer showed greater antioxidant activity (IC50 = 47.46 ppm) than the crown conformer (IC50 = 78.46 ppm). Additionally, it was observed that the mixture of both conformers presented lower antioxidant activity than either conformer in isolation. The results found suggest that the chair conformer has efficient antioxidant activity that makes it a potential target for further research.

[Nutritional evolution during the early stages of hematopoietic stem cell transplantation: importance of the phase angle]. / Evolución nutricional durante las primeras etapas del trasplante de precursores hematopoyéticos: importancia del ángulo de fase.

INTRODUCTION: the aim of this study is to compare the changes in anthropometry, dynamometry and bioelectrical impedance analysis (BIA) of patients undergoing autologous and allogeneic hematopoietic stem cell transplantation (HSCT) after the conditioning period and one-week post-transplantation, and to assess whether these early changes are associated with the development of later complications. METHODS: prospective cohort study. Nutritional status was assessed by anthropometry, dynamometry and BIA at three different defined times: T1, time of admission; T2, after the myeloablative conditioning period; and T3, day + 8 post-HSCT. RESULTS: forty patients were evaluated, 17 received autologous HSCT (TAU) and 23 received allogeneic HSCT (TAL). Patients with TAL had higher mortality and hospital stay compared to patients with TAU. Those who developed graft versus host disease (GVHD) presented a lower phase angle (PA) than those who did not develop this complication (T2: TAL PA with GVHD 4.8° vs TAL PA without GVHD 5.5°, p = 0.007). The patients who died during the hospital stay are all from the TAL group and had PA less than 5° at T3. Weight, body mass index (BMI) and fat-free mass index (FMI) did not show a significant impact, and all of them were influenced by total body water. CONCLUSIONS: early nutritional evaluation of these patients by phase angle seems promising, since it is not altered by water retention and can be evaluated before anthropometric changes occur.

A single dose of dihydrocapsiate does not improve neuromuscular performance in resistance-trained young adults: A randomised, triple-blinded, placebo-controlled, crossover trial.

Capsinoids may exert ergogenic effects on resistance exercises. However, the acute effects of capsinoids on neuromuscular performance in humans are unknown. Here, we aimed to investigate the acute effects of dihydrocapsiate on lower- and upper-body neuromuscular performance parameters in resistance-trained individuals. 25 young adults (n = 6 women; age = 26 ± 3 years; body mass index = 24.3 ± 2.8 kg/m2) with ≥ 1-year resistance training experience were included in this triple-blind (participants, intervention researchers, and data analysts were blinded), placebo-controlled, crossover study. Lower- and upper-body ballistic strength (countermovement jump [CMJ] height and bench press throw [BPT] peak velocity), maximum dynamic strength (estimated 1 repetition maximum in squat and bench press [BP]), and strength-endurance (mean set velocity [squat] and number of repetitions to failure [bench press]) were assessed in 2 independent sessions (≥7 days separation). Participants ingested 12 mg of dihydrocapsiate or placebo 30 min before each trial. We found no significant differences between dihydrocapsiate and placebo conditions in ballistic strength, (CMJ height 33.20 ± 8.07 vs 33.32 ± 7.85 cm; BPT peak velocity 2.82 ± 0.77 vs 2.82 ± 0.74 m/s) maximal dynamic strength (estimated squat 1RM: 123.76 ± 40.63 vs 122.66 ± 40.97 kg; estimated BP 1RM: 99.47 ± 43.09 vs 99.60 ± 43.34 kg), and strength-endurance (squat mean set velocity 0.66 ± 0.07 vs 0.66 ± 0.05 m/s; number BP repetitions to failure 13.00 ± 3.56 vs 13.00 ± 4.78) (all P ≥ 0.703). We conclude that dihydrocapsiate does not acutely improve neuromuscular performance in trained young adults.

Capsinoids ­ non-pungent analogs of capsaicin ­ have been recently proposed as potential ergogenic compounds in humans.However, the effects of a single dose of capsinoids on neuromuscular performance parameters in humans remains unknown.12 mg of dihydrocapsiate does not improve neuromuscular performance in resistance-trained young adults.Dihydrocapsiate should not be recommended as an ergogenic aid to acutely increase neuromuscular performance.

Copper(I)-Catalyzed Alkyne-Azide Cycloaddition (CuAAC) "Click" Reaction: A Powerful Tool for Functionalizing Polyhydroxylated Platforms.

Click chemistry is currently one of the most used tools for the generation of complex organic molecules. The advantages of using click chemistry in organic synthesis are remarkable; in many cases, the reactions occur under mild conditions and are free of solvents, with high yields and short reaction times. This makes it an extraordinarily effective and viable alternative for obtaining complex/conjugated molecules. In this review, the use of click chemistry CuAAC is especially emphasized for polyhydroxylated platforms such as resorcinarenes or calixarenes, focusing mainly on aspects of synthesis, specifically conditions, reagents, and methodologies.

Efficient Separation of C-Tetramethylcalix[4]resorcinarene Conformers by Means of Reversed-Phase Solid-Phase Extraction.

A reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed to study the conformer formation generated during the reaction for obtaining C-tetramethylcalix[4]resorcinarene. The chromatographic method was used to design a strategy for purifying the reaction products, using solid-phase extraction columns (RP-SPE) and gradient elution. The chromatographic profiles of the cyclocondensation reaction between resorcinol and acetaldehyde show the presence of three products under the different reaction and precipitation conditions studied. Using RP-SPE, it was possible to enrich the products, which were later characterized by means of RP-HPLC and 1H nuclear magnetic resonance (NMR). This investigation explored and established a new method for RP-HPLC analysis and RP-SPE separation of conformational isomers obtained in the formation reaction of C-tetramethylcalix[4]resorcinarene.

Caffeine ingestion attenuates diurnal variation of lower-body ballistic performance in resistance-trained women.

ABSTRACTThe present study investigates the effect of an acute intake of caffeine on the diurnal variation of neuromuscular performance in resistance-trained women. A total of 15 resistance-trained women participated in the current triple-blind, placebo-controlled, crossover experimental study. We assessed neuromuscular performance (i.e. ballistic (countermovement jump [CMJ] height and bench press throw [BPT] peak velocity), maximal strength (squat and bench press [BP] one-repetition maximum [1RM]), and strength-endurance [average velocity of the set during squat and number of repetitions-to-failure in BP]) four times at within 7 days. The participants ingested an acute dose of caffeine (3 mg/kg) or a placebo at 9-11 am and/or 17-19 pm. CMJ height (P = .016) and BP peak velocity (P = .012) were higher in the afternoon than in the morning. Compared to placebo, caffeine intake increased CMJ height by 3.1% in the morning and 1.6% in the afternoon (P = .035), but it had no effect on BPT peak velocity (P = .381). Maximal strength and strength-endurance performances were not affected by the time-of-day or caffeine intake (all P > .3). No significant interaction (time-of-day x substance) was observed in any of the above-mentioned outcomes (all P > .1). In conclusion, an acute dose of caffeine in the morning was effective to restore CMJ performance to levels found in the afternoon, while this effect was not observed neither in BPTpeak velocity nor in lower- and upper-body maximal strength and strength-endurance performance. Moreover, lower- and upper-body ballistic performance were greater in the afternoon than in the morning in resistance-trained women, while the acute intake of caffeine was only effective to increase CMJ height.HighlightsBallistic performance is probably higher in the afternoon than in the morning in resistance-trained women.An acute intake of caffeine is effective to increase countermovement jump performance.The ingestion of an acute dose of caffeine in the morning restored countermovement jump performance to levels found in the afternoon.

A nutritional intervention for moderate altitude endurance preparation: A case report.

Background: Moderate altitudes carry physiological and metabolic changes that can dampen exercise performance. Fortunately, these changes can be modulated by an optimal nutritional intervention. This case study represents the first nutritional intervention of a moderate altitude athlete. These results may help to establish well-designed nutritional guidelines for moderate altitude sports athletes. Case presentation: This case study examined the effects of a 11-week nutritional intervention on body composition, muscle strength, cardiorespiratory fitness, resting and exercise nutrient oxidation, and subjective sleep quality, in a male high-level moderate altitude athlete with a very light non-exercise activity thermogenesis. During the 11-week of nutritional intervention, 2800-3500 kcal/day, 6.8-8.9 g/kg/day of carbohydrates, 1.2-1.7 g/kg/day of protein, and 1-2.5 g/kg/day of fat were prescribed. Different specific considerations were also included, such as: iron supplementation, antioxidants increment in different phases, and ergogenic aids (i.e. creatine and beta-alanine). Our results demonstrated a decrease in adiposity and an increase in fat-free mass. In parallel, the athlete improved muscle strength, and therefore endurance adaptations after a maximal effort test (i.e. enhancement of the heart rate recovery). After the intervention, the athlete not only increased the carbohydrate oxidation during exercise and resting conditions but also improved his subjective sleep quality. Conclusions: Our results suggest that a nutritional intervention based on the endurance nutritional recommendations and adapted to the altitude physiological peculiarities can induce body re-composition, improve physiological adaptations to effort, and upgrade the substrate oxidation in a moderate altitude high-level athletes.

Evidence of Isomerization in the Michael-Type Thiol-Maleimide Addition: Click Reaction between L-Cysteine and 6-Maleimidehexanoic Acid.

The reaction between L-cysteine (Cys) and 6-maleimidohexanoic acid (Mhx) in an aqueous medium at different levels of pH was analyzed via RP-HPLC, finding the presence of two reaction products throughout the evaluated pH range. By means of solid-phase extraction (SPE), it was possible to separate the products and obtain isolated profiles enriched up to 80%. The products were analyzed individually through mass spectrometry, DAD-HPLC, NMR 1H, 13C, and two-dimensional evidence of isomerization between the hydrogen atoms of the α-amino and the thiol group present in the cysteine. Thus, it was concluded that the products obtained corresponded to a mixture of the isomer Cys-S-Mhx, where the adduct is formed by a thioether bond, and the isomer Cys-NH-Mhx, in which the union is driven by the amino group. We consider that the phenomenon of isomerization is an important finding, since it has not previously been reported for this reaction.

Removal of Toxic Metal Ions Using Poly(BuMA-co-EDMA) Modified with C-Tetra(nonyl)calix[4]resorcinarene.

A copolymer of poly(BuMA-co-EDMA) modified with C-tetra(nonyl)calix[4]resorcinarene was obtained via the impregnation method. The formation of the modified copolymer was confirmed and investigated using various techniques; in this way, the presence of calix[4]resorcinarene was confirmed by FT-IR spectroscopy and by high resolution transmission electron microscopy. The modified copolymer was used for the removal of highly toxic cations (Pb2+, Hg2+, and Cd2+) from aqueous solutions. To perform the removal, we used the batch sorption technique and the effects of time of contact, pH, and volume of sample on the effective sorption were determined. The best results were observed for Pb2+ extraction, which was comparatively more efficient. Adsorption-desorption experiments revealed that the modified copolymer could be used for several cycles without significant loss of adsorption capacity. Finally, the results showed that the modified copolymer application is highly efficient for the removal of lead ions from aqueous solutions.

Benzodiazepines: Their Use either as Essential Medicines or as Toxics Substances.

This review highlights the nature, characteristics, properties, pharmacological differences between different types of benzodiazepines, the mechanism of action in the central nervous system, and the degradation of benzodiazepines. In the end, the efforts to reduce the benzodiazepines' adverse effects are shown and a reflection is made on the responsible uses of these medications.

Caffeine increases maximal fat oxidation during a graded exercise test: is there a diurnal variation?

BACKGROUND: There is evidence that caffeine increases the maximal fat oxidation rate (MFO) and aerobic capacity, which are known to be lower in the morning than in the afternoon. This paper examines the effect of caffeine intake on the diurnal variation of MFO during a graded exercise test in active men. METHODS: Using a triple-blind, placebo-controlled, crossover experimental design, 15 active caffeine-naïve men (age: 32 ± 7 years) completed a graded exercise test four times at seven-day intervals. The subjects ingested 3 mg/kg of caffeine or a placebo at 8 am in the morning and 5 pm in the afternoon (each subject completed tests under all four conditions in a random order). A graded cycling test was performed. MFO and maximum oxygen uptake (VO2max) were measured by indirect calorimetry, and the intensity of exercise that elicited MFO (Fatmax) calculated. RESULTS: MFO, Fatmax and VO2max were significantly higher in the afternoon than in the morning (all P < 0.05). Compared to the placebo, caffeine increased mean MFO by 10.7% (0.28 ± 0.10 vs. 0.31 ± 0.09 g/min respectively, P < 0.001) in the morning, and by a mean 29.0% (0.31 ± 0.09 vs. 0.40 ± 0.10 g/min, P < 0.001) in the afternoon. Caffeine also increased mean Fatmax by 11.1% (36.9 ± 14.4 [placebo] vs. 41.0 ± 13.1%, P = 0.005) in the morning, and by 13.1% (42.0 ± 11.6 vs. 47.5 ± 10.8%, P = 0.008) in the afternoon. CONCLUSION: These findings confirm the previously reported diurnal variation in the whole-body fat oxidation rate during graded exercise in active caffeine-naïve men, and indicate that the acute ingestion of 3 mg/kg of caffeine increases MFO, Fatmax and VO2max independent of the time of day. TRIAL REGISTRATION: NCT04320446 . Registered 25 March 2020 - Retrospectively registered.

Obtaining an immunoaffinity monolithic material: poly(GMA-co-EDMA) functionalized with an HPV-derived peptide using a thiol-maleimide reaction.

Metabolites have great potential for the design of biomarkers, since their presence or absence provides valuable information about a biological system. In this context, polyclonal antibodies are important metabolites for diagnostic procedures, but in some pathologies, it has been found that these metabolites are present at low concentrations, so it could be difficult to detect them. In this investigation, an organic monolithic material of poly(GMA-co-EDMA) was functionalized with a peptide via Michael addition (thiol-maleimide) click chemistry. The peptide, covalently bound to the monolith, contains the SPINNTKPHEAR sequence derived from the human papilloma virus L1 protein. It was determined that the obtained monolithic support allows selectively isolating polyclonal antibodies against the SPINNTKPHEAR sequence, since they are retained on the chemical surface of the material by an immunoaffinity interaction. The monolithic material functionalization protocol reported here could be applied to incorporate any peptide with a terminal cysteine in order to recover a specific analyte. A new method was developed for isolating and pre-concentrating antibodies using monolithic materials, which could contribute to the improvement of disease detection strategies based on immunoaffinity interactions.

Preparation of Methacrylate-based Polymers Modified with Chiral Resorcinarenes and Their Evaluation as Sorbents in Norepinephrine Microextraction.

Aminomethylation reactions between chiral amino compounds (S)-(-)-1-phenylethylamine and l-proline with tetranonylresorcinarene and tetra-(4-hydroxyphenyl)resorcinarene in presence of formaldehyde were studied. The reaction between l-proline and resorcinarenes generated regioselectively chiral tetra-Mannich bases, due to the molecular incorporation of the fragment of the chiral amino acid. On the other hand, tetranonylresorcinarene and (S)-(-)-1-phenylethylamine formed regio- and diasteroselectively chiral tetrabenzoxazines, both by chiral auxiliary functionalization and by the transformation of the molecular structure that confers inherent chirality. The products obtained were characterized using IR, 1H-NMR, 13C-NMR, COSY, HMQC, and HMBC techniques. The reaction of (S)-(-)-1-phenylethylamine with tetra-(4-hydroxyphenyl)resorcinarene did not proceed under the experimental conditions. Once the chiral aminomethylated tetra-(4-hydroxyphenyl)resorcinarene was obtained, the chemical modification of poly(GMA-co-EDMA) was studied, and the results showed an efficient incorporation of the aminomethylated compound. For the physical modification, chiral aminomethylated tetranonylresorcinarenes were employed, finding that the incorporation of modified resorcinarenes occurs, but with less efficiency than that observed using chemical modification. The modified polymers were characterized via FT-IR, scanning electron microscopy imaging, and elemental analysis. Finally, polymers modified with chiral resorcinarenes were used as sorbents in norepinephrine microextraction; for practical purposes, artificial urine was prepared and used. To perform the microextraction, the decision was made to use the modern rotating-disk sorptive extraction technique (RDSE), because of its analytical attributes as a green, or eco-friendly, technique. According to the results, the method preliminarily validated for the determination of norepinephrine in artificial urine shows that the modified polymer with chiral derivative of tetra-(4-hydroxyphenyl)resorcinarene worked effectively as a new sorbent phase for the quantitative microextraction of norepinephrine, exhibiting high stability and homogeneity of composition and structure within the working range.

Aminomethylated Calix[4]resorcinarenes as Modifying Agents for Glycidyl Methacrylate (GMA) Rigid Copolymers Surface.

Functionalization of tetrapropylcalix[4]resorcinarene, tetrapentylcalix[4]resorcinarene, tetranonylcalix[4]resorcinarene, and tetra-(4-hydroxyphenyl)calix[4]resorcinarene by means of aminomethylation reactions with the amino acids ß-alanine and l-proline in the presence of aqueous formaldehyde was carried out. When ß-alanine was used, the reaction products were tetrabenzoxazines. The reaction with tetra-(4-hydroxyphenyl)calix[4]resorcinarene did not proceed under the experimental conditions; therefore, l-proline was used, and the corresponding tetra-Mannich base was regio- and diasteroselectively formed. The products were characterized via FT-IR, 1H NMR, 13C NMR, and elemental analysis. With these aminomethylated-calix[4]resorcinarenes, the chemical surface modification of the copolymers poly(GMA-co-EDMA) and poly(BMA-co-EDMA-co-MMA) in a basic medium was studied. The results were quite satisfactory, obtaining the corresponding copolymers functionalized by nucleophilic substitution reaction and ring-opening between the carboxyl group of the upper rim of aliphatic calix[4]resorcinarenes and the hydroxyl group of the lower rim in the aromatic calix[4]resorcinarene and the epoxy group of the glycidyl methacrylate residue of each copolymer. The modified copolymers were characterized via FT-IR, scanning electron microscopy imaging, and elemental analysis. Finally, the modified copolymer surfaces exhibited interaction with peptides, showing their potential application in chromatographic separation techniques such as high-performance liquid chromatography.

Dynamics of stress generation and reduction in the nursing team at an oncology center. / Dinâmica de geração e dissipação do estresse na equipe de enfermagem num centro de oncologia.

OBJECTIVE: to represent the dynamics of stress generation, accumulation and reduction in the nursing team at an oncology therapy center. METHOD: a mathematical simulation model of system dynamics was developed based on data collection in loco. The model served to test the impact of three policies aimed at reducing stress in the team, namely i) increase in the service load; ii) increase in the size of shift teams and iii) reduction of service hours per bed. RESULTS: the model showed that the policy of increasing the size of the team obtained the best results, with the absenteeism index stabilizing at 8%; staff at leave also stabilizing at 4-5 people per month, as well as accumulated stress reduced to baseline levels. CONCLUSION: measures to monitor physical and emotional demands, hiring staff, better technical training for so-called stressful activities, and a better distribution of tasks can be effective in reducing absenteeism rates and improving the quality of life of these workers.

Procesos y estrategias de innovación curricular en la carrera de Enfermería. Universidad Arturo Prat, Chile / Processes and Strategies of Curricular Innovation in the Nursing Major, Arturo Prat University, Chile

Introducción: La educación, en particular la universitaria, hace pertinente las modificaciones curriculares que analicen el trasfondo de los escenarios actuales, los que tensionan y conflictúan los modos tradicionales necesarios para estructurar y configurar la arquitectura curricular. Objetivo: Rediseñar procesos y estrategias de una estructuración curricular basada en competencias en la carrera de Enfermería de la Universidad Arturo Prat, Chile. Métodos: Estudio descriptivo-explicativo, con metodología cuantitativa-cualitativa. Como método teórico se utilizó análisis-síntesis, enfoque sistémico, inducción-deducción, y análisis documental y de contenido de literatura. El universo, estudiado en su conjunto, estuvo constituido por la totalidad de los docentes de la unidad académica. Resultados: Se obtuvo un proyecto curricular de pregrado, que incorporó políticas y lineamientos emanados del Consejo de Rectores de Universidades Chilenas; estrategias y patrones del modelo educativo universitario; y recomendaciones promovidas por la Asociación Chilena de Educación en Enfermería en formación profesional. La propuesta caracterizó un proceso reflexivo y crítico de los académicos participantes. El rediseño siguió los desafíos de la globalización universitaria, al abrir espacios educativo-innovadores, según Tunning, en formación por competencias genéricas. En esta innovación se abordaron 4 como sello institucional y 6 competencias específicas, los cuales tributaron al perfil de egreso del estudiante. Conclusiones: Se logró un nuevo plan de estudio secuenciado, integrado y propicio para formar profesionales de enfermería competentes, con alta calidad, el cual aportó las herramientas para brindar acciones de cuidados, con seguridad y pertinencia. Esta estrategia buscó configurar un nuevo modelo de universidad que, sin descuidar la solvencia cognoscitiva y la competencia profesional, puso énfasis, preferentemente, en la formación de sujetos reflexivos, responsables, críticos, innovadores y versátiles(AU)

Introduction: Education, particularly university education, validates the applicability of the curricular modifications that analyze the background of the current contexts, which stress and conflict with the traditional ways necessary to structure and configure the curricular architecture. Objective: To redesign processes and strategies within acompetence-based curricular structuring in the Nursing major of Arturo Prat University, Chile. Methods: Descriptive-explanatory study, with a quantitative-qualitative methodology. As a theoretical method, we used analysis-synthesis, systemic approach, induction-deduction, and documentary and content analysis of literature. The study population, studied as a whole, was made up of all the teachers in the academic unit. Results: An undergraduate curriculum project was obtained, which incorporated policies and guidelines derived from the Council of Rectors of Chilean universities, strategies and patterns of the university educational model, and recommendations promoted by the Chilean Association of Nursing Education regarding vocational training. The proposal characterized a reflexive and critical process of the participating academics. The redesign followed the challenges of university globalization, by opening educational-innovative spaces, according to Tunning, in training based in generic skills. In this innovation, we addressed four of them an institutional seal and six specific competences, which contributed to the student's working profile. Conclusions: A new sequenced, integrated and conducive study plan was achieved to train competent nursing professionals, with high quality, which gave the tools to provide care actions, with safety and relevance. This strategy sought to configure a new university model that, without neglecting cognitive solvency and professional competence, emphasize, preferably, on the formation of reflective, responsible, critical, innovative and versatile subjects(AU)

Analysis by RP-HPLC and Purification by RP-SPE of the C-Tetra(p-hydroxyphenyl)resorcinolarene Crown and Chair Stereoisomers.

A method for the separation of stereoisomer mixture of the octol C-tetra(p-hydroxyphenyl)calix[4]resorcinarene that was obtained by an acid cyclocondensation reaction between resorcinol and benzaldehyde is reported in this paper. A crude product from octol formation reaction was analyzed by reverse-phase high-performance liquid chromatography (RP-HPLC), and two well-resolved signals corresponding to the crown and chair isomers were found. A reverse phase in solid-phase extraction (RP-SPE) protocol allowed the separation of the two stereoisomers with high purity of each isomer. Finally, the crude and purified stereoisomers were characterized by using FT-IR, 1H-NMR, and 13C-NMR techniques, confirming the chemical identity of the two isomers and the efficiency in the separation process.

Host-Guest Recognition of Pesticides by Calixarenes.

This article is based on a review of the literature and our own experience with toxicological molecules. We explain the nature of calix[n]arenes and as their recognized properties are used to detect compounds of toxicological interest, mainly the most important pesticide families such as organophosphorated, organochlorine compounds, pyrethroid insecticides, carbamate fungicides, and herbicides, using different techniques. In addition, we show the role of the macrocycle and its interactions, and the advantage of using this type of compound for improving conventional techniques, where the phenomenon of recognition is very important, such as chromatography, solid-phased extraction, and the development of specific sensors, among others and Even we also show the use of this macrocycle for detoxication procedures in vivo. In this way, we display as the multiple possibilities of functionalization of the calix[n]arenes makes these versatile molecules in the phenomena of specific recognition. Finally, This review highlights the main analytical methods reported in the literature for determination of plaguicides by host-guest interaction with calixarenes. In this way, among the available analytical tools, chromatographic, and electrochemical-based methods are the most used techniques for the detection and to quantify plaguicides using calixarenes.

Dinâmica de geração e dissipação do estresse na equipe de enfermagem num centro de oncologia / Dynamics of stress generation and reduction in the nursing team at an oncology center / Dinámica de generación y disipación del estrés en el equipo de enfermería en un centro de oncología

Objetivo: representar a dinâmica de geração, acumulação e dissipação do estresse na equipe de enfermagem em um centro de terapia oncológica. Método: um modelo de simulação matemático de dinâmica de sistemas foi desenvolvido com base na coleta de dados in loco. O modelo serviu para testar o impacto de três políticas direcionadas a reduzir o estresse na equipe: i) incremento na carga de atendimento; ii) incremento do tamanho das equipes de turno e iii) redução de horas de atendimento por leito. Resultados: o modelo demonstrou que a política de incremento de tamanho da equipe obteve os melhores resultados, sintetizados com o índice de absenteísmo, estabilizando-se em 8%; pessoal afastado também se estabilizando em 4-5 pessoas por mês, bem como o estresse acumulado reduzido aos níveis do cenário base. Conclusão: as medidas no sentido de acompanhamento das demandas físicas e emocionais, a contratação de pessoal, um melhor treinamento técnico para as atividades ditas estressantes e uma melhor distribuição de tarefas podem ser eficazes na redução dos índices de absenteísmo e melhorar a qualidade de vida desses trabalhadores.

Objective: to represent the dynamics of stress generation, accumulation and reduction in the nursing team at an oncology therapy center. Method: a mathematical simulation model of system dynamics was developed based on data collection in loco. The model served to test the impact of three policies aimed at reducing stress in the team, namely i) increase in the service load; ii) increase in the size of shift teams and iii) reduction of service hours per bed. Results: the model showed that the policy of increasing the size of the team obtained the best results, with the absenteeism index stabilizing at 8%; staff at leave also stabilizing at 4-5 people per month, as well as accumulated stress reduced to baseline levels. Conclusion: measures to monitor physical and emotional demands, hiring staff, better technical training for so-called stressful activities, and a better distribution of tasks can be effective in reducing absenteeism rates and improving the quality of life of these workers.

Objetivo: representar la dinámica de generación, acumulación y disipación del estrés en el equipo de enfermería en un centro de terapia oncológica. Método: un modelo de simulación matemático de dinámica de sistemas fue desarrollado basado en la recolección de datos in loco. El modelo sirvió para testar el impacto de tres políticas dirigidas a reducir el estrés en el equipo: i) incremento en la carga de atendimiento; ii) incremento del tamaño de los equipos de turno y iii) reducción de horas de atendimiento por lecho. Resultados: el modelo demostró que la política de incremento de tamaño del equipo obtuvo los mejores resultados, sintetizados con el índice de ausentismo estabilizándose en 8%; personal alejado también estabilizándose en 4-5 personas por mes, así como el estrés acumulado reducido a los niveles del escenario base. Conclusión: las medidas en el sentido de acompañamiento de las demandas físicas y emocionales, la contratación de personal, mejor entrenamiento técnico para actividades llamadas estresantes y una mejor distribución de tareas pueden ser eficaces en la reducción de los índices de ausentismo y mejorar la calidad de vida de esos trabajadores.

Conformational Aspects of the O-acetylation of C-tetra(phenyl)calixpyrogallol[4]arene.

Reaction between pyrogallol and benzaldehyde results in a conformational mixture of C-tetra(phenyl)pyrogallol[4]arene (crown and chair). The conformer mixture was separated using crystallization procedures and the structures were determined using FTIR, ¹H-NMR, and 13C-NMR. O-acetylation of C-tetra(phenyl)pyrogallol[4]arene (chair) with acetic anhydride, in pyridine results in the formation of dodecaacetyl-tetra(phenyl)pyrogallol[4]arene. The structure was determined using ¹H-NMR and 13C-NMR finding that the product maintains the conformation of the starting conformer. On the other hand, the O-acetylation reaction of C-tetra(phenyl)pirogallol[4]arene (crown) under same conditions proceeded efficiently, and its structure was determined using ¹H-NMR and 13C-NMR. Dynamic ¹H-NMR of acetylated pyrogallolarene was studied by means of variable temperature in DMSO-d6 solution, and it revealed that two conformers are formed in the solution. Boat conformations for acetylated pyrogallolarene showed a slow interconversion at room temperature.