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Antioxidants agents play an essential role in the food industry for improving the oxidative stability of food products. In the last years, the search for new natural antioxidants has increased due to the potential high toxicity of chemical additives. Therefore, the synthesis and evaluation of the antioxidant activity in peptides is a field of current research. In this study, we performed a Quantitative Structure Activity Relationship analysis (QSAR) of cysteine-containing 19 dipeptides and 19 tripeptides. The main objective is to bring information on the relationship between the structure of peptides and their antioxidant activity. For this purpose, 1D and 2D molecular descriptors were calculated using the PaDEL software, which provides information about the structure, shape, size, charge, polarity, solubility and other aspects of the compounds. Different QSAR model for di- and tripeptides were developed. The statistic parameters for di-peptides model (R2train = 0.947 and R2test = 0.804) and for tripeptide models (R2train = 0.923 and R2test = 0.847) indicate that the generated models have high predictive capacity. Then, the influence of the cysteine position was analyzed predicting the antioxidant activity for new di- and tripeptides, and comparing them with glutathione. In dipeptides, excepting SC, TC and VC, the activity increases when cysteine is at the N-terminal position. For tripeptides, we observed a notable increase in activity when cysteine is placed in the N-terminal position.

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This study provides accurate results for the electronic stopping cross sections of H, He, N, and Ne in silicon in low to intermediate energy ranges using various non-perturbative theoretical methods, including real-time time-dependent density functional theory, transport cross section, and induced-density approach. Recent experimental findings [Ntemou et al., Phys. Rev. B 107, 155145 (2023)] revealed discrepancies between the estimates of density functional theory and the observed values. We show that these discrepancies vanish by considering the nonuniform electron density of the deeper silicon bands for ion velocities approaching zero (v → 0). This indicates that mechanisms such as "elevator" and "promotion," which can dynamically excite deeper-band electrons, are active, enabling a localized free-electron gas to emulate ion energy loss, as pointed out by Lim et al. [Phys. Rev. Lett. 116, 043201 (2016)]. The observation and the description of a velocity-proportionality breakdown in electronic stopping cross sections at very low velocities are considered to be a signature of the contributions of deeper-band electrons.

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Introducción: El envejecimiento de la población en todo el mundo es un fenómeno progresivo y Chile no se queda atrás frente a esto. Actualmente existe un subprograma de climaterio mujeres entre los 45 a 64 años, que presenta diversas acciones y propósitos. Objetivo: Describir la cobertura de la aplicación de la Menopause Rating Scale (MRS) e indicación de terapia de reemplazo hormonal en mujeres inscritas en los CESFAM de la comuna de Pedro Aguirre Cerda. Método: Descriptivo transversal. Resultados: La cobertura de aplicación de MRS en mujeres entre 45-64 años fue de un 62,6%. Un 34,3% de mujeres presentaron un puntaje MRS alterado, indicándose terapia hormonal en un 37,8% de los casos, en las indicaciones un 21,8% eran usuarias candidatas acorde a criterios médicos y un 78,2% no lo eran. Conclusiones: Se debe aumentar la cobertura de MRS y recursos para exámenes de laboratorio, de imágenes y capacitaciones, esto para mejorar la entrega de las prestaciones en el subprograma climaterio.

Introduction: The aging of the population worldwide is a progressive phenomenon and Chile is not lagging behind in this. Currently, there is a climacteric subprogram for women between 45 and 64 years of age, which has various actions and purposes. Objective: To describe the coverage of the application of the Menopause Rating Scale (MRS) and indication of hormone replacement therapy in women enrolled in the CESFAM of the commune of Pedro Aguirre Cerda. Method: Cross-sectional descriptive study. Results: The coverage of the MRS application in women between 45-64 years old was 62.6%. A 34.3% of women presented an altered MRS score, indicating hormone therapy in 37.8% of the cases, 21.8% of the indications were candidates according to medical criteria and 78.2% were not. Conclusions: There is a lack of labs and images tests in the climacteric controls, resulting in a mayor number of women no candidates to the hormonal therapy according to medical criteria.

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This comprehensive study delves into the intricate interplay between protons and organic polymers, offering insights into proton therapy in cancer treatment. Focusing on the influence of the spatial electron density distribution on stopping power estimates, we employed real-time time-dependent density functional theory coupled with the Penn method. Surprisingly, the assumption of electron density homogeneity in polymers is fundamentally flawed, resulting in an overestimation of stopping power values at energies below 2 MeV. Moreover, the Bragg rule application in specific compounds exhibited significant deviations from experimental data around the stopping maximum, challenging established norms.

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OBJECTIVES: To evaluate a clinical pharmacist's inclusion in emergency department (ED) care in terms of the effect on on 30-day revisits after discharge from the ED and patient satisfaction. MATERIAL AND METHODS: Randomized, controlled parallel-group pragmatic trial in a university hospital ED. Recruited patients were randomly assigned to a control group for standard care only or an intervention group to receive standard care plus the attention of a clinical pharmacist integrated into the care team to optimize the selection and evaluation of medications and provide pharmacotherapeutic education on the patient's discharge. The primary outcome was unplanned revisits within 30 days after discharge because of the same complaint that led to the initial ED visit. Between-group differences were analyzed with Kaplan-Meier survival curves and log-rank tests. The association between the intervention and time to the outcome event was explored with multivariate Cox proportional hazard regression analysis. RESULTS: A total of 1001 patients were enrolled (intervention, 500; control, 501). Patients in both groups were similar. A majority were women (61.5%), and the median age (interquartile range) was 51 years (33-65 years). The pharmacist's intervention significantly reduced the number of 30-day revisits to any ED: 25 (6.3%) revisited vs 66 (16.7%) in the control group. The adjusted hazard ratio (aHR) was 0.29 (95% CI, 0.17-0.50). Fifteen patients (3.0%) from the intervention group revisited the same ED vs 32 (6.5%) from the control group (aHR, 0.46 [95% CI, 0.24-0.87]). More patients expressed satisfaction in the intervention group (87.2%) than in the control group ( 83.2%) (P .05). CONCLUSION: Including a clinical pharmacist in ED care substantially reduces the number of 30-day revisits and increases patient satisfaction.

OBJETIVO: Determinar el efecto de la inclusión del farmacéutico clínico en el servicio de urgencias (SU) en las reconsultas durante 30 días posalta y la satisfacción de los pacientes. METODO: Ensayo clínico controlado, aleatorizado, paralelo y pragmático, realizado en el SU de un hospital universitario. Los pacientes reclutados fueron asignados aleatoriamente al grupo control (GC) que recibió la atención habitual o al grupo intervenido (GI) que recibió además la atención de un farmacéutico clínico, el cual se integró al equipo clínico para optimizar la selección, evaluación y educación farmacoterapéutica en el SU y al alta. El desenlace primario fue reconsultas no programadas 30 días posaltarelacionadas con la atención inicial al SU. Las diferencias entre grupos se analizaron por curvas de supervivencia de Kaplan-Meier y prueba de log-rank. La asociación entre intervención y tiempo al evento fue analizada mediante regresión multivariada de riesgos proporcionales de Cox y se expresó como hazard ratio ajustada (HRa). RESULTADOS: Un total de 1.001 pacientes ingresaron al estudio (GI = 500 y GC = 501). Ambos grupos eran similares, predominaron las mujeres (61,5%), edad 51 años (RIC: 33-65). La intervención redujo significativamente las reconsultas a cualquier centro durante 30 días posalta comparado con GC [25 (6,3%) vs 66 (16,7%); HRa: 0,29 (IC 95%: 0,17-0,50)] y para el mismo centro [15 (3,0%) vs 32 (6,5%); HRa: 0,46 (IC 95%: 0,24-0,87)]. La satisfacción del usuario fue mayor en el GI que GC (87,2% vs 83,2%; p 0,05). CONCLUSIONES: La inclusión del farmacéutico clínico en un SU reduce sustancialmente las reconsultas durante 30 días posalta y mejora la satisfacción de los usuarios.

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Pharmacogenomics (PGx) is considered an emergent field in developing countries. Research on PGx in the Latin American and the Caribbean (LAC) region remains scarce, with limited information in some populations. Thus, extrapolations are complicated, especially in mixed populations. In this paper, we reviewed and analyzed pharmacogenomic knowledge among the LAC scientific and clinical community and examined barriers to clinical application. We performed a search for publications and clinical trials in the field worldwide and evaluated the contribution of LAC. Next, we conducted a regional structured survey that evaluated a list of 14 potential barriers to the clinical implementation of biomarkers based on their importance. In addition, a paired list of 54 genes/drugs was analyzed to determine an association between biomarkers and response to genomic medicine. This survey was compared to a previous survey performed in 2014 to assess progress in the region. The search results indicated that Latin American and Caribbean countries have contributed 3.44% of the total publications and 2.45% of the PGx-related clinical trials worldwide thus far. A total of 106 professionals from 17 countries answered the survey. Six major groups of barriers were identified. Despite the region's continuous efforts in the last decade, the primary barrier to PGx implementation in LAC remains the same, the "need for guidelines, processes, and protocols for the clinical application of pharmacogenetics/pharmacogenomics". Cost-effectiveness issues are considered critical factors in the region. Items related to the reluctance of clinicians are currently less relevant. Based on the survey results, the highest ranked (96%-99%) gene/drug pairs perceived as important were CYP2D6/tamoxifen, CYP3A5/tacrolimus, CYP2D6/opioids, DPYD/fluoropyrimidines, TMPT/thiopurines, CYP2D6/tricyclic antidepressants, CYP2C19/tricyclic antidepressants, NUDT15/thiopurines, CYP2B6/efavirenz, and CYP2C19/clopidogrel. In conclusion, although the global contribution of LAC countries remains low in the PGx field, a relevant improvement has been observed in the region. The perception of the usefulness of PGx tests in biomedical community has drastically changed, raising awareness among physicians, which suggests a promising future in the clinical applications of PGx in LAC.

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Genomic relationships can be computed with dense genome-wide genotypes through different methods, either based on identity-by-state (IBS) or identity-by-descent (IBD). The latter has been shown to increase the accuracy of both estimated relationships and predicted breeding values. However, it is not clear whether an IBD approach would achieve greater heritability ( h 2 ) and predictive ability ( r ̂ y , y ̂ ) than its IBS counterpart for data with low-depth pedigrees. Here, we compare both approaches in terms of the estimated of h 2 and r ̂ y , y ̂ , using data on meat quality and carcass traits recorded in experimental crossbred pigs, with a pedigree constrained to only three generations. Three animal models were fitted which differed on the relationship matrix: an IBS model ( G IBS ), an IBD (defined within the known pedigree) model ( G IBD ), and a pedigree model ( A 22 ). In 9 of 20 traits, the range of increase for the estimates of σ u 2 and h 2 was 1.2-2.9 times greater with G IBS and G IBD models than with A 22 . Whereas for all traits, both parameters were similar between genomic models. The r ̂ y , y ̂ of the genomic models was higher compared to A 22 . A scarce increment in r ̂ y , y ̂ was found with G IBS when compared to G IBD , most likely due to the former recovering sizeable relationships among founder F0 animals.

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In the two decades of continuous development of genomic selection, a great variety of models have been proposed to make predictions from the information available in dense marker panels. Besides deciding which particular model to use, practitioners also need to make many minor choices for those parameters in the model which are not typically estimated by the data (so called "hyper-parameters"). When the focus is placed on predictions, most of these decisions are made in a direction sought to optimize predictive accuracy. Here we discuss and illustrate using publicly available crop datasets the use of cross validation to make many such decisions. In particular, we emphasize the importance of paired comparisons to achieve high power in the comparison between candidate models, as well as the need to define notions of relevance in the difference between their performances. Regarding the latter, we borrow the idea of equivalence margins from clinical research and introduce new statistical tests. We conclude that most hyper-parameters can be learnt from the data by either minimizing REML or by using weakly-informative priors, with good predictive results. In particular, the default options in a popular software are generally competitive with the optimal values. With regard to the performance assessments themselves, we conclude that the paired k-fold cross validation is a generally applicable and statistically powerful methodology to assess differences in model accuracies. Coupled with the definition of equivalence margins based on expected genetic gain, it becomes a useful tool for breeders.

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Introduction: Infections in hematological cancer patients are common and usually life-threatening; avoiding them could decrease morbidity, mortality, and cost. Genes associated with antineoplastics' pharmacokinetics or with the immune/inflammatory response could explain variability in infection occurrence. Objective: To build a pharmacogenetic-based algorithm to predict the incidence of infections in patients undergoing cytotoxic chemotherapy. Methods: Prospective cohort study in adult patients receiving cytotoxic chemotherapy to treat leukemia, lymphoma, or myeloma in two hospitals in Santiago, Chile. We constructed the predictive model using logistic regression. We assessed thirteen genetic polymorphisms (including nine pharmacokinetic-related genes and four inflammatory response-related genes) and sociodemographic/clinical variables to be incorporated into the model. The model's calibration and discrimination were used to compare models; they were assessed by the Hosmer-Lemeshow goodness-of-fit test and area under the ROC curve, respectively, in association with Pseudo-R2. Results: We analyzed 203 chemotherapy cycles in 50 patients (47.8 ± 16.1 years; 56% women), including 13 (26%) with acute lymphoblastic and 12 (24%) with myeloblastic leukemia. Pharmacokinetics-related polymorphisms incorporated into the model were CYP3A4 rs2242480C>T and OAT4 rs11231809T>A. Immune/inflammatory response-related polymorphisms were TLR2 rs4696480T>A and IL-6 rs1800796C>G. Clinical/demographic variables incorporated into the model were chemotherapy type and cycle, diagnosis, days in neutropenia, age, and sex. The Pseudo-R2 was 0.56, the p-value of the Hosmer-Lemeshow test was 0.98, showing good goodness-of-fit, and the area under the ROC curve was 0.93, showing good diagnostic accuracy. Conclusions: Genetics can help to predict infections in patients undergoing chemotherapy. This algorithm should be validated and could be used to save lives, decrease economic costs, and optimize limited health resources.