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The present work deals with a comprehensive computational theoretical study of the molecular CO and O2 adsorption on 3d single atoms (M/MgO(100)). The study is based on the chemical elements of the 3d row, as they represent an economic advantage compared with the so-called noble metals. The present study has been performed employing density functional theory calculations. Through the representation of the metastable states, we perform a synergetic analysis of the CO oxidation reaction to find trends that suggest the possible use of new candidates such as Ni/MgO(100) or Cu/MgO(100) single-atom catalysts, for this type of redox reaction. We found that Ni and Cu produce energetically viable CO to CO2 reactions. Ni and Cu atoms show the greatest diffusion barrier and are the best candidates due to their low sintering capability. The energetic and electronic properties of the single Cu and Ni atoms on MgO (100) give them the best characteristics to help in the CO oxidation process. [ABSTRACT FROM AUTHOR]

A comprehensive computational study on the oxygen molecule (O2) adsorption and activation on bimetallic Au–Ir subnanometer clusters supported on TiO2(101)— up to five atoms in size—is performed. A global optimization density functional theory-based basin-hopping algorithm is used to determine putative global minima configurations of both mono- and bimetallic clusters supported on the metal oxide surface for all sizes and compositions. Our results indicate a strong cluster-oxide interaction for monometallic Ir clusters with calculated adsorption energy (Eads) values ranging from −3.11 to −5.91 eV. Similar values are calculated for bimetallic Au–Ir clusters (−3.21 up to −5.69 eV). However, weaker Eads values are calculated for Au clusters (ranging from −0.66 to −2.07 eV). As a general trend, we demonstrate that for supported Au–Ir clusters on TiO2(101), those Ir atoms preferentially occupy cluster-oxide interface positions while acting as anchor sites for the Au atoms. The overall geometric arrangements of the putative global minima configurations define O2 adsorption and dissociation, particularly involving the monometallic Au5 and Ir5 as well as the bimetallic Au2Ir3 and Au3Ir2 supported clusters. Spontaneous O2 dissociation is observed on both Ir5 and on the Ir-metallic part of Au3Ir2 and Au2Ir3 supported clusters. This is in sharp contrast with supported Au5, where a large activation energy is needed (1.90 eV). Interestingly, for Au5, we observe that molecular O2 adsorption is favorable at the cluster/oxide interface, followed by a smaller dissociation barrier (0.71 eV). From a single cluster catalysis point of view, our results have strong implications in the ongoing understanding of oxide supported bimetallic while providing a useful first insight into the continuous in silico design of novel subnanometer catalysts. [ABSTRACT FROM AUTHOR]

In the present work, we discuss the electronic properties of supported dispersed bimetallic clusters with respect to their size, geometry, and Aun/Agm (n + m = 6) composition. We have studied with supercell-density functional theory calculations the role of the charge transfer from the MgO defective support toward the cluster in the activation of O2 by AunAgm clusters. We first considered gas-phase clusters with different atomic compositions; then, we deposited all of them on a pristine (100)MgO surface and finally on a more realistic (100)MgO F-center. We performed a global and unrestricted search of the (cluster + surface) geometry. The Mexican enhanced genetic algorithm has been used to exhaustively explore the potential energy surface. Our results show that O2 activation depends on the Aun/Agm ratio. It has been found that both metals involved play different and important roles toward (a) the actual O2 dissociation and (b) weakening of the oxygen-cluster bond, which, in turn, may promote the possibility of a catalytic process to take place, such as the oxidation process of CO and NOx among others. [ABSTRACT FROM AUTHOR]

Understanding the physical mechanisms of thiolated molecules adsorption on metal surfaces has required copious research, particularly on Au–cysteine systems due to the affinity of sulfur molecules to gold surfaces, as well as the interesting structural modifications that this strong interaction induces and the peculiar optical, chiroptical, and electronic properties of Au(SR) systems. Here, we present vibrational experimental data on the adsorption of L‐ and D‐cysteine on small gold nanoparticles (<2 nm) by means of Raman spectroscopy. L‐ and D‐cysteine molecules adopt the same strained conformation upon adsorption on colloidal gold nanoparticles, regaining structure due to the stabilization that the gold nanoparticle induces on the cysteine, reflected in the recuperation of vibrational bands from their polymorphically distinctive crystalline forms. Through the analysis of Raman vibrational modifications after adsorption, we found experimental evidence that confirms a stabilized cysteine conformation locating the carboxyl group in the antiposition (PC isomeric rotamer) for both molecules. This result is supported by extensive density functional theory (DFT) calculations and simulated Raman spectra, considering zwitterionic cysteine adsorbed on a Au34 cluster, emulating experimental nanoparticle sizes. Our Raman spectroscopy experimental and DFT results determine one of the oxygen atoms of the carboxyl group as a second adsorption site after the sulfur atom, confirming that independent of its polymorphism and enantiomerism, zwitterionic cysteine interacts with gold nanoparticles through the thiol group and the carboxyl group as adsorption sites. [ABSTRACT FROM AUTHOR]

This work proposes a method to generate a greater and bigger knowledge from a data set. The GKPFCM clustering algorithm is used for that. So, for a given number of clusters it identifies their location and their approximate shape. The relations among the variables of the data set can be found with these clusters, and they can be expressed as conditional rules such as "If/Then." The GKPFCM provides the membership values and the typicality values from which a knowledge base is generated through two fuzzy models, and this can be used in order to classify new data and to determine if these new data are typical, atypical or noise. So, a better expert decision can be made based on the results of these models. [ABSTRACT FROM AUTHOR]

Abstract Background The Spanish Palliative Care Strategy recommends an intermediate level of training for primary care physicians in order to provide them with knowledge and skills. Most of the training involves face-to-face courses but increasing pressures on physicians have resulted in fewer opportunities for provision of and attendance to this type of training. The effectiveness of on-line continuing medical education in terms of its impact on clinical practice has been scarcely studied. Its effect in relation to palliative care for primary care physicians is currently unknown, in terms of improvement in patient's quality of life and main caregiver's satisfaction. There is uncertainty too in terms of any potential benefits of asynchronous communication and interaction among on-line education participants, as well as of the effect of the learning process. The authors have developed an on-line educational model for palliative care which has been applied to primary care physicians in order to measure its effectiveness regarding knowledge, attitude towards palliative care, and physician's satisfaction in comparison with a control group. The effectiveness evaluation at 18 months and the impact on the quality of life of patients managed by the physicians, and the main caregiver's satisfaction will be addressed in a different paper. Methods Randomized controlled educational trial to compared, on a first stage, the knowledge and attitude of primary care physicians regarding palliative care for advanced cancer patients, as well as satisfaction in those who followed an on-line palliative care training program with tutorship, using a Moodle Platform vs. traditional education. Results 169 physicians were included, 85 in the intervention group and 84 in the control group, of which five were excluded. Finally 82 participants per group were analyzed. There were significant differences in favor of the intervention group, in terms of knowledge (mean 4.6; CI 95%: 2.8 to 6.5 (p = 0.0001), scale range 0-33), confidence in symptom management (p = 0.02) and confidence in terms of communication (p = 0.038). Useful aspects were pointed out, as well as others to be improved in future applications. The satisfaction of the intervention group was high. Conclusions The results of this study show that there was a significant increase of knowledge of 14%-20% and a significant increase in the perception of confidence in symptom management and communication in the intervention group in comparison with the control group that received traditional methods of education in palliative care or no educational activity at all. The overall satisfaction with the intervention was good-very good for most participants. This on-line educational model seems a useful tool for palliative care training in primary care physicians who have a high opinion about the integration of palliative care within primary care. The results of this study support the suggestion that learning effectiveness should be currently investigated comparing different Internet interventions, instead of Internet vs. no intervention. Trial Registration German Clinical Trials Register DRKS00000694

Background: Due to increased exposure to health hazards, patients with cancer are at a higher risk of developing infective endocarditis (IE), which in turn maximizes their risk of poor outcomes. This study aimed to analyze IE events in patients with cancer and matched controls., Methods: We conducted a retrospective case-control study in four third-level centers in Mexico City between 2006 and 2022. Patients with IE were identified; cases (patients with cancer) were matched in a 1:2 ratio with controls (patients without cancer). Baseline characteristics, factors associated with IE, and outcomes were assessed in both groups., Results: A total of 108 patients were included (36 cases and 72 controls). After logistic regression analysis, the risk factors independently associated with IE in cases were obesity (adjusted odds ratio [aOR] 9.03, 95 % CI 1.5-51.8), surgery within six months before IE (aOR 6.23, 95 % CI 1.8-21.5), and invasive procedures within six months prior to IE (aOR 3.89, 95 % CI 1.15-13.1). Healthcare-associated IE was more common in these cases, as were systemic embolic episodes. Subjects with S. aureus IE were more prone to experience systemic embolization. There were no differences in mortality between the groups., Conclusion: In this study, risk factors associated with the healthcare environment were more frequent in patients with IE and cancer. S. aureus was a common culprit and was associated with systemic embolization., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could potentially influence the work reported in this article., (Copyright © 2024 Instituto Mexicano del Seguro Social (IMSS). Published by Elsevier Inc. All rights reserved.)

Background: Fontan circulation maintains an elevated venous pressure; this promotes venous and lymphatic congestion and may lead to late circuit failure. Our objective was to determine the association between thoracic lymphatic perfusion patterns assessed by magnetic resonance imaging and late Fontan failure., Methodology: A retrospective study was performed. We included patients who underwent the Fontan procedure between January 2005 and December 2019 and who were evaluated with lymphatic mapping using magnetic resonance imaging. Lymphatic abnormalities were classified into four types. The prevalence of late failure was determined, and logistic regression analysis was performed to establish the association between the variables of interest and the outcome., Results: Fifty-four patients were included with a mean age at surgery of 8.8 years ± 3.5 years; 42.6% (n = 23) were men. The most frequent diagnosis was tricuspid atresia (50%, n = 27), and the Fontan procedures were mainly performed using an extracardiac conduit (96.3%, n = 52). The prevalence of late Fontan failure was 35.2%. The lymphatic perfusion patterns observed were Type 1 in 25.9% (n = 14), Type 2 in 46.3% (n = 25), Type 3 in 25.9% (n = 14), and Type 4 in 1.8% (n = 1), with no differences in relation to late failure. ( p = 0.42). The age at surgery was found to be a factor associated with the late Fontan failure (OR: 1.23; 95% CI: 1.02-1.48; p = 0.02)., Conclusions: One-third of patients with Fontan circulation may experience late failure, not significantly associated with lymphatic changes, but when the total cavopulmonary connection is completed at an older age.

Background: In patients with transposition of the great arteries and an arterial switch operation (TGA-ASO) right ventricular outflow tract (RVOT) obstruction is a common complication requiring one or more RVOT interventions., Objectives: We aimed to assess cardiopulmonary exercise capacity and right ventricular function in patients stratified for type of RVOT intervention., Methods: TGA-ASO patients (≥16 years) were stratified by type of RVOT intervention. The following outcome parameters were included: predicted (%) peak oxygen uptake (peak VO2), tricuspid annular plane systolic excursion (TAPSE), tricuspid Lateral Annular Systolic Velocity (TV S'), right ventricle (RV)-arterial coupling (defined as TAPSE/RV systolic pressure ratio), and N-terminal proBNP (NT-proBNP)., Results: 447 TGA patients with a mean age of 25.0 (interquartile range (IQR) 21-29) years were included. Patients without previous RVOT intervention (n = 338, 76%) had a significantly higher predicted peak VO2 (78.0 ± 17.4%) compared to patients with single approach catheter-based RVOT intervention (73.7 ± 12.7%), single approach surgical RVOT intervention (73.8 ± 28.1%), and patients with multiple approach RVOT intervention (66.2 ± 14.0%, p = 0.021). RV-arterial coupling was found to be significantly lower in patients with prior catheter-based and/or surgical RVOT intervention compared to patients without any RVOT intervention (p = 0.029)., Conclusions: TGA patients after a successful arterial switch repair have a decreased exercise capacity. A considerable amount of TGA patients with either catheter or surgical RVOT intervention perform significantly worse compared to patients without RVOT interventions., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In view of the competing assignments regarding the most stable isomer of the B 70 boron cluster including the quasi-planar and bilayer structures, we reinvestigated the structural motifs of B 70 using a genetic algorithm for structure search (MEGA) in conjunction with density functional theory computations using the PBE functional. The quasi-planar structure was also constructed using the topological leapfrog algorithm. The latter search aimed to give us unique insight into its formation and the growth pattern of boron clusters. Also, the di-anionic state of B 70 was explored. Our extensive search suggested a competition between the quasi-planar, tubular and bilayer isomers for the ground state of B 70 in both neutral and dianionic states. While the bilayer form is more stable in the neutral state, the quasi-planar counterpart becomes more stable in the dianionic B 70 2- . The stability arises due to the fact that the B 70 2- dianion possesses 50 π electrons that satisfy the disk aromaticity model rule. These results tend to extend the stabilization of the quasi-planar structure upon negative charge addition previously found in small size boron clusters to larger sizes.

Right atrial isomerism (RAI) is a complex entity with varying diagnostic and treatment outcomes due to its rarity. Treatment options range from palliative to corrective surgeries, resulting in heterogeneous outcomes. The aim of this study was to analyze the results obtained after cardiac surgery in patients with RAI. A retrospective study was conducted, including patients diagnosed with RAI who underwent cardiac surgery. Their follow-up was from 1 January 2010 to 31 March 2020. Demographic characteristics and perioperative conditions were described. Thirty-eight patients were included, the median age was 4 years (IQR 2-9.2) and 57.9% were men. The main diagnoses were atrioventricular canal (63.2%) and pulmonary stenosis (55.3%). The most common surgical procedures were modified Blalock-Taussig shunt (65.8%) and total cavopulmonary connection with an extracardiac conduit fenestrated without cardiopulmonary bypass (15.9%). We did not find any factors associated with negative outcomes in these patients. The overall survival was 86.8%, with a better outcome in those who did not require reintubation (log rank, p < 0.01). The survival of RAI was similar to other centers. Individuals with RAI should be evaluated rigorously to determine an adequate repair strategy, considering high morbidity and mortality.

Background: In recent decades, adults living with congenital heart disease (ACHD) have improved their survival, thus increasing their predisposition to the onset of cardiometabolic risk factors and chronic health conditions., Objectives: The purpose of this study was to describe cardiometabolic risk profiles in the ACHD population and their relationship to congenital heart disease (CHD) lesion complexity., Methods: We performed a cross-sectional study from ACHD in a third-tier referral center in Mexico City. The association between cardiometabolic risk factors and CHD complexity was estimated using logistic regression models., Results: Our study cohort included 1,171 ACHD patients (median age: 31 [IQR: 23.2-42.7] years, male 63.6%). Cardiac diagnosis was classified as mild (44.9%), moderate (37.8%), and severe (17.2%) CHD complexity. Low high-density lipoprotein cholesterol (55%) was the most common cardiometabolic risk factor; followed by insulin resistance (54.5%) and prediabetes (52.4%). Patients with mild and moderate CHD had a higher prevalence of obesity and metabolic syndrome, while patients with severe CHD had a higher prevalence of hyperuricemia and subclinical hypothyroidism. In the logistic regression analysis, the severity of CHD was associated with higher odds of hyperuricemia (moderate CHD, OR: 1.87; 95% CI: 1.20-2.93; P  = 0.010; severe CHD, OR: 2.75; 95% CI: 1.64-4.62; P  < 0.001) and lower risks of metabolic syndrome (OR: 0.61; 95% CI: 0.41-0.91; P  = 0.010), prediabetes (OR: 0.58; 95% CI: 0.42-0.81; P  < 0.001), and arterial hypertension (OR: 0.49; 95% CI: 0.33-0.74; P  < 0.001) compared with mild CHD complexity., Conclusions: We observed high rates of cardiometabolic risk factors in Mexican ACHD patients and these risk profiles varied by CHD lesion complexity. These results highlight the need for ongoing metabolic health surveillance in the ACHD population., Competing Interests: The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (© 2023 The Authors.)

Purpose: There are currently no standard definitions for assessing the severity of Clostridioides difficile infection (CDI) in cancer patients. We evaluated the performance of scoring systems for severity and analyzed risk factors for mortality in a cancer cohort., Methods: We conducted an observational study in patients with cancer and CDI. We calculated the incidence of hospital-onset (HO-CDI) and community-onset health-care facility associated (CO-HCFA-CDI) episodes. We classified severity using five prognostic scales and calculated sensitivity, specificity, positive (PPV), and negative predictive values (NPV) for mortality and intensive care unit (ICU) admission. In addition, multivariate regression was performed to assess variables associated with mortality., Results: The HO-CDI and CO-HCFA-CDI incidence rates were 3.7 cases/10,000 patient-days and 1.9 cases/1,000 admissions, respectively. ESCMID criteria showed the higher sensitivity (97%, 95% CI; 85-100%) and NPV (98%, 95% CI; 85-100%), while ATLAS (≥ 6 points) had the highest specificity (95%, 95% CI; 90-98%) for 30-day all-cause mortality; similar performance was observed for ICU admission. Characteristics associated with fatal outcome were neutropenia (≤ 100 cells/ml) (aOR; 3.03, 95% CI; 1.05-8.74, p = 0.040), male gender (aOR; 2.90, 95% CI; 1.08-7.80, p = 0.034), high serum creatinine (aOR; 1.71, 95% CI; 1.09-2.70, p = 0.020), and albumin (aOR; 0.17, 95% CI; 0.07-0.42, p < 0.001)., Conclusions: Some of the current scales may not be appropriate to discriminate severity in patients with cancer. The variables in this study associated with unfavorable outcomes could be evaluated in prospective studies to develop prognostic scores that identify susceptible patients, especially in immunocompromised populations., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The identification of carbapenemase-producing Enterobacterales and Pseudomonas aeruginosa is important for treating and controlling hospital infections. The recommended methods for their identification require a long waiting time, technical training, and expertise. Lateral flow immunoassays such as NG-Test CARBA 5 ® overcome these needs. We analyzed 84 clinical isolates of carbapenem-resistant Enterobacterales and P. aeruginosa from four different hospitals in a two-year period. Antimicrobial resistance patterns were confirmed with the broth dilution method. Evaluation of KPC, VIM, NDM, IMP, and OXA-48-like enzymes was performed and compared to NG-Test CARBA 5 and phenotypic assays. Enterobacterales represented 69% of isolates and P. aeruginosa represented 31%. Carbapenemase-producing strains were 51 (88%) of Enterobacterales and 23 (88.4%) of P. aeruginosa ; 20 (34%) and 23 (88%) were Class B ß-lactamases, respectively. The NG-Test CARBA 5 ® assay for Enterobacterales showed high sensitivity (98%), specificity (100%), and PPV (100%); however, it did not for P. aeruginosa . The Kappa concordance coefficient was 0.92 for Enterobacterales and 0.52 for P. aeruginosa . NG-Test CARBA 5 ® is a fast and easy-to-use assay. In Enterobacterales, we found excellent agreement in our comparison with molecular tests. Despite the low agreement in P. aeruginosa , we suggest that this test could be used as a complementary tool.

Purpose: To evaluate the clinical and surgical outcomes among children with bicuspid aortic valve who underwent cardiac surgery., Methods: This observational and retrospective study included patients with a diagnosis of bicuspid aortic valve who underwent cardiac surgery between January 1, 2003, and March 31, 2020. Demographic characteristics and perioperative conditions were described., Results: One hundred and sixteen patients were included, with a mean age of 12.4 ± 4.2 years; 63.2% were male. The most frequent diagnosis was congenital aortic stenosis (23.5%), followed by connective tissue disorders (16%). Mechanical aortic prostheses were used in 87.7% of cases, with a mean size of 21 ± 2.6 mm. The main factors associated with mortality were valve prosthesis dysfunction (odds ratio [OR]: 12.44; 95% confidence interval [CI]: 1.05-147.48; p = .04) and reoperation (OR: 24.29; 95% CI: 1.03-570.08; p = .04). The overall survival was 87.9%, with better outcomes among those who did not undergo reoperation (Log Rank, p = .01)., Conclusions: Outcomes after aortic valve replacement in children with bicuspid aortic valve are excellent in the short and long term, regardless of using mechanical or biological prostheses., (© 2022 Wiley Periodicals LLC.)

Introduction: Clostridioides difficile infection (CDI) is recognized as the leading cause of nosocomial diarrhea. This study describes CDI's clinical characteristics, risk factors, and outcomes in the cancer population., Methods: We conducted a case-control study on cancer patients from 2015-2018 at the Instituto Nacional de Cancerologia in Mexico. CDI case was defined as diarrhea episode and positive polymerase chain reaction (PCR) for toxigenic strains. Controls were cancer diagnosis-matched patients with diarrhea and negative PCR. Healthcare Facility-Onset (HO-CDI) and Community-Onset, Healthcare Facility-Associated (CO-HCFA-CDI) rates were calculated. For assessing associations, univariate and multivariate logistic regression analyses were conducted., Results: We included 148 CDI cases and 148 controls. The CDI rate was 4.1 per 10,000 patient-days and 2.1 per 1,000 patient admissions for HO-CDI and CO-HCFA-CDI episodes, respectively. Clinical characteristics associated with CDI were fever, abdominal pain, and ≥4 episodes of diarrhea/24h. Previous use of proton pump inhibitors (P=.003), fluoroquinolones (P=.016), and cephalosporins (P=.026) increased the risk for CDI acquisition, while higher age (P=.022) and male gender (P=.015) were related to severe episodes. Thirty-day all-cause mortality was higher among CDI patients (18%) than controls (9%)., Conclusion: The CDI rate was lower compared to other series. The incidence of CO-HCFA-CDI episodes increased, and HO-CDI cases decreased from 2016 to 2018. Risk factors for acquisition and severe infection were similar to those reported in non-cancer populations., (Copyright © 2022 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)