An Emergent Change in Epidemiologic and Microbiological Characteristics of Bloodstream Infections in Adults With Febrile Neutropenia Resulting From Chemotherapy for Acute Leukemia and Lymphoma at Reference Centers in Chile, Ecuador, and Peru.

Background: Febrile neutropenia is a life-threatening condition commonly observed in patients with hematologic malignancies. The aim of this article is to provide updated knowledge about bloodstream infections in febrile neutropenia episodes within the Andean region of Latin America. Method: This retrospective study was based in 6 hospitals in Chile, Ecuador, and Peru and included adult patients with acute leukemia or lymphoma and febrile neutropenia between January 2019 and December 2020. Results: Of the 416 febrile neutropenia episodes, 38.7% had a bloodstream infection, 86% of which were caused by gram-negative rods, with Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa being the most frequently identified bacteria. K pneumoniae isolates were more frequently resistant than E coli to cefotaxime (65% vs 39.6%), piperacillin-tazobactam (56.7% vs 27.1%), and imipenem (35% vs 2.1%) and were more frequently multidrug resistant (61.7% vs 12.5%). Among P aeruginosa, 26.7% were resistant to ceftazidime, piperacillin-tazobactam, and imipenem, and 23.3% were multidrug resistant. Overall 30-day mortality was 19.8%, being higher with vs without a bloodstream infection (26.7% vs 15.3%, P = .005). Fever duration was also significantly longer, as well as periods of neutropenia and length of hospital stay for patients with bloodstream infection. Additionally, the 30-day mortality rate was higher for episodes with inappropriate vs appropriate empirical antibiotic therapy (41.2% vs 26.6%, P = .139). Conclusions: Considering the high rates of bacteria-resistant infection and 30-day mortality, it is imperative to establish strategies that reduce the frequency of bloodstream infections, increasing early identification of patients at higher risks of multidrug bacteria resistance, and updating existing empirical antibiotic recommendations.

SARS-CoV-2 vaccine booster in solid organ transplant recipients previously immunised with inactivated versus mRNA vaccines: A prospective cohort study.

Background: Solid-organ transplant (SOT) recipients have worse COVID-19 outcomes than general population and effective immunisation in these patients is essential but more difficult to reach. We aimed to determine the immunogenicity of an mRNA SARS-CoV-2 vaccine booster in SOT recipients previously immunised with either inactivated or homologous SARS-CoV-2 mRNA vaccine. Methods: Prospective cohort study of SOT recipients under medical care at Red de Salud UC-CHRISTUS, Chile, previously vaccinated with either CoronaVac or BNT162b2. All participants received a BNT162b2 vaccine booster. The primary study end point was anti-SARS-CoV-2 total IgG antibodies (TAb) seropositivity at 8-12 weeks (56-84 days) post booster. Secondary end points included neutralising antibodies (NAb) and specific T-cell responses. Findings: A total of 140 (50% kidney, 38% liver, 6% heart) SOT recipients (mean age 54 [13.6] years; 64 [46%] women) were included. Of them, 62 had homologous (three doses of BNT162b2) and 78 heterologous vaccine schedules (two doses of CoronaVac followed by BNT162b2 booster). Boosters were received at a median of 21.3 weeks after primary vaccination. The proportion achieving TAb seropositivity (82.3% vs 65.4%, P = 0.035) and NAb positivity (77.4% vs 55.1%, P = 0.007) were higher for the homologous versus the heterologous group. On the other hand, the number of IFN-γ and IL-2 secreting SARS-CoV-2-specific T-cells did not differ significantly between groups. Interpretation: This cohort study shows that homologous mRNA vaccine priming plus boosting in SOT recipients, reaches a significantly higher humoral immune response than inactivated SARS-CoV-2 vaccine priming followed by heterologous mRNA booster. Funding: School of Medicine, UC-Chile and ANID.ClinicalTrials.gov ID: NCT05124509.

Air Pollution and Cardiorespiratory Changes in Older Adults Living in a Polluted Area in Central Chile.

One recognized cause of cardiorespiratory diseases is air pollution. Older adults (OA) are one of the most vulnerable groups that suffer from its adverse effects. The objective of the study was to analyze the association between exposure to air pollution and changes in cardiorespiratory variables in OA. Observational prospective cohort study. Health questionnaires, blood pressure (BP) measurements, lung functions, respiratory symptoms, physical activity levels, and physical fitness in high and low exposure to air pollution were all methods used in evaluating OAs in communes with high contamination rates. Linear and logistic models were created to adjust for variables of interest. A total of 92 OA participated in this study. 73.9% of the subjects were women with 72.3 ± 5.6 years. 46.7% were obese, while 12.1% consumed tobacco. The most prevalent diseases found were hypertension, diabetes, and cardiovascular disease. Adjusted linear models maintained an increase for systolic BP of 6.77 mmHg (95% CI: 1.04-12.51), and diastolic of 3.51 mmHg (95% CI: 0.72-6.29), during the period of high exposure to air pollution. The adjusted logistic regression model indicated that, during the period of high exposure to air pollution increase the respiratory symptoms 4 times more (OR: 4.43, 95% CI: 2.07-10.04) in the OA. The results are consistent with an adverse effect on cardiorespiratory variables in periods of high exposure to air pollution in the OA population.

Evaluación de la percepción de riesgo cardiovascular en mujeres posterior a un programa de rehabilitación cardíaca / Perception of cardiovascular risk in women after a rehabilitation program

RESUMEN: Introducción: La rehabilitación cardíaca después de padecer un evento cardiovascular (CV) grave es un proceso en el cual el paciente establece una relación cercana con el equipo médico, brindando la oportunidad de conocer factores psicosociales que influyeron en el desenlace cardíaco y los eventuales aprendizajes de la experiencia. El objetivo de este estudio fue conocer la percepción sobre su propia salud de mujeres que participaron de un programa de rehabilitación cardíaca. Método: Se invitó a participar a 35 mujeres de 35 a 75 años con diverso nivel educativo, ingreso familiar y situación laboral. Los datos se recolectaron por medio de entrevistas presenciales semiestructuradas. Resultados: A pesar de haber pasado por un proceso de rehabilitación posterior a un evento CV las mujeres mencionaron en forma mayoritaria al cáncer de mama como la principal eventual causa de muerte. En relación con los factores de riesgo de CV, el más nombrado fue el estrés (57%), aunque solo el 29% de las entrevistadas realizó con posterioridad actividades orientadas a su manejo y control. En cuanto a las motivaciones más frecuentes para realizar cambios de hábitos, destacaron el cuidado de la familia (29%), el vivir más (26%) y el deseo de sentirse mejor (23%). Conclusión: Estos resultados sugieren la necesidad de una educación más integral en la mujer durante la rehabilitación, promoviendo no solo hábitos más saludables desde el punto de vista físico, sino también psicológico. Se sugiere integrar el manejo del estrés en los programas de prevención y rehabilitación CV.

ABSTRACT: Introduction: After suffering a serious cardiovascular event (CV), cardiac rehabilitation is a process in which the patient establishes a close relationship with the medical team, providing an opportunity to learn about psychosocial factors that influence cardiac outcome and eventual learnings from the experience. The objective of this study was to learn about women´s perception of their own health after participating in a cardiac rehabilitation program. Method: 35 women from 35 to 75 years of age with varying educational level, household income and employment status were invited to participate. Data was collected through semi-structured face-to-face interviews. Results: Women mentioned breast cancer as the leading cause of death (60%) despite having gone through a post-CV rehabilitation process. Stress was mentioned as the main CV risk factor (57%). Only 29% of responders subsequently carried out activities aimed at their management and control. The most common motivations for making changes in habits, were family care (29%), living longer (26%) and a desire to feel better (23%). Conclusion: These results suggest the need for a more comprehensive education in women during rehabilitation, promoting not only healthier habits from a physical but also from a psychological points of view. The introduction of stress management into CV prevention and rehabilitation programs is suggested.

Percepción en médicos del impacto de la enfermedad cardiovascular en la mortalidad femenina / Knowledge among physicians of the main cause of death in women

Background: There is a misconception that the main cause of death among women is breast cancer, even among physicians, who may neglect cardiovascular preventive measures in this gender Aim: To assess the knowledge among physicians about the main cause of death among women. Material and methods: A survey was answered by 231 physicians attending a Cardiology and a Gynecology Meeting. Results: Sixty eight percent of respondents indicated that cardiovascular diseases are the main cause of death among women. A higher proportion of specialists than trainees, answered correctly the question (72 and 56% respectively). No gender differences in the answers were recorded. Conclusions: The knowledge about cardiovascular risk in women should be reinforced among physicians.

[Knowledge among physicians of the main cause of death in women]. / Percepción en médicos del impacto de la enfermedad cardiovascular en la mortalidad femenina.

BACKGROUND: There is a misconception that the main cause of death among women is breast cancer, even among physicians, who may neglect cardiovascular preventive measures in this gender Aim: To assess the knowledge among physicians about the main cause of death among women. MATERIAL AND METHODS: A survey was answered by 231 physicians attending a Cardiology and a Gynecology Meeting. RESULTS: Sixty eight percent of respondents indicated that cardiovascular diseases are the main cause of death among women. A higher proportion of specialists than trainees, answered correctly the question (72 and 56% respectively). No gender differences in the answers were recorded. CONCLUSIONS: The knowledge about cardiovascular risk in women should be reinforced among physicians.

Tools for in silico target fishing.

Computational target fishing methods are designed to identify the most probable target of a query molecule. This process may allow the prediction of the bioactivity of a compound, the identification of the mode of action of known drugs, the detection of drug polypharmacology, drug repositioning or the prediction of the adverse effects of a compound. The large amount of information regarding the bioactivity of thousands of small molecules now allows the development of these types of methods. In recent years, we have witnessed the emergence of many methods for in silico target fishing. Most of these methods are based on the similarity principle, i.e., that similar molecules might bind to the same targets and have similar bioactivities. However, the difficult validation of target fishing methods hinders comparisons of the performance of each method. In this review, we describe the different methods developed for target prediction, the bioactivity databases most frequently used by these methods, and the publicly available programs and servers that enable non-specialist users to obtain these types of predictions. It is expected that target prediction will have a large impact on drug development and on the functional food industry.

Molecular fingerprint similarity search in virtual screening.

Molecular fingerprints have been used for a long time now in drug discovery and virtual screening. Their ease of use (requiring little to no configuration) and the speed at which substructure and similarity searches can be performed with them - paired with a virtual screening performance similar to other more complex methods - is the reason for their popularity. However, there are many types of fingerprints, each representing a different aspect of the molecule, which can greatly affect search performance. This review focuses on commonly used fingerprint algorithms, their usage in virtual screening, and the software packages and online tools that provide these algorithms.

Field measurements of the atmospheric dry deposition fluxes and velocities of polycyclic aromatic hydrocarbons to the global oceans.

The atmospheric dry deposition fluxes of 16 polycyclic aromatic hydrocarbons (PAHs) have been measured, for the first time, in the tropical and subtropical Atlantic, Pacific, and Indian Oceans. Depositional fluxes for fine (0.7-2.7 µm) and coarse (>2.7 µm) aerosol fractions were simultaneously determined with the suspended aerosol phase concentrations, allowing the determination of PAH deposition velocities (vD). PAH dry deposition fluxes (FDD) bound to coarse aerosols were higher than those of fine aerosols for 83% of the measurements. Average FDD for total (fine + coarse) Σ16PAHs (sum of 16 individual PAHs) ranged from 8.33 ng m(-2)d(-1) to 52.38 ng m(-2)d(-1). Mean FDD for coarse aerosol's individual PAHs ranged between 0.13 ng m(-2)d(-1) (Perylene) and 1.96 ng m(-2)d(-1) (Methyl Pyrene), and for the fine aerosol fraction these ranged between 0.06 ng m(-2)d(-1) (Dimethyl Pyrene) and 1.25 ng m(-2)d(-1) (Methyl Chrysene). The estimated deposition velocities went from the highest mean vD for Methyl Chrysene (0.17-13.30 cm s(-1)), followed by Dibenzo(ah)Anthracene (0.29-1.38 cm s(-1)), and other high MW PAHs to minimum values of vD for Dimethyl Pyrene (<0.04 cm s(-1)) and Pyrene (<0.06 cm s(-1)). Dry depositional processes depend on the concentration of PAHs in the suspended aerosol, but also on physicochemical properties and environmental variables (vapor pressure, wind speed, and on the affinity of aerosols for depositing to the sea surface). Empirical parametrizations are proposed to predict the dry depositional velocities of semivolatile organic compounds to the global oceans.

The good, the bad and the dubious: VHELIBS, a validation helper for ligands and binding sites.

BACKGROUND: Many Protein Data Bank (PDB) users assume that the deposited structural models are of high quality but forget that these models are derived from the interpretation of experimental data. The accuracy of atom coordinates is not homogeneous between models or throughout the same model. To avoid basing a research project on a flawed model, we present a tool for assessing the quality of ligands and binding sites in crystallographic models from the PDB. RESULTS: The Validation HElper for LIgands and Binding Sites (VHELIBS) is software that aims to ease the validation of binding site and ligand coordinates for non-crystallographers (i.e., users with little or no crystallography knowledge). Using a convenient graphical user interface, it allows one to check how ligand and binding site coordinates fit to the electron density map. VHELIBS can use models from either the PDB or the PDB_REDO databank of re-refined and re-built crystallographic models. The user can specify threshold values for a series of properties related to the fit of coordinates to electron density (Real Space R, Real Space Correlation Coefficient and average occupancy are used by default). VHELIBS will automatically classify residues and ligands as Good, Dubious or Bad based on the specified limits. The user is also able to visually check the quality of the fit of residues and ligands to the electron density map and reclassify them if needed. CONCLUSIONS: VHELIBS allows inexperienced users to examine the binding site and the ligand coordinates in relation to the experimental data. This is an important step to evaluate models for their fitness for drug discovery purposes such as structure-based pharmacophore development and protein-ligand docking experiments.

Polychlorinated biphenyls, hexachlorocyclohexanes and hexachlorobenzene in seawater and phytoplankton from the Southern Ocean (Weddell, South Scotia, and Bellingshausen Seas).

The Southern Ocean is one of the most pristine environments in the world, but is nonetheless affected by inputs of persistent organic pollutants (POPs). In the present work, we report the concentrations of hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), and 26 polychlorinated biphenyl (PCBs) congeners in seawater and phytoplankton from samples obtained during three Antarctic cruises in 2005, 2008, and 2009. The levels of PCBs, HCHs, and HCB are low in comparison to the few previous reports for this region and studies from other oceans. The long-term decline of POP concentrations in the Southern Ocean seawater since early 1980 is consistent with half-lives of 3.4 and 5.7 years for HCHs and PCBs, respectively. There is a large variability of PCBs, HCHs, and HCB concentrations in water and phytoplankton within the Bransfield Strait, South Scotia, Weddell, and Bellingshausen Seas that masks the differences between the studied Seas. However, the variability of PCBs concentrations in phytoplankton is significantly correlated with phytoplankton biomass, with lower concentrations in the most productive waters. This trend is more apparent for the more hydrophobic congeners, consistent with the role of settling fluxes of organic matter decreasing the concentrations of hydrophobic POPs in productive waters. The present work reports the most extensive data set on concentrations in seawater and phytoplankton for the Southern Ocean, and points to the important biogeochemical drivers, such as settling and degradation, influencing the occurrence of POPs in the ocean.

Identification of novel human dipeptidyl peptidase-IV inhibitors of natural origin (Part II): in silico prediction in antidiabetic extracts.

BACKGROUND: Natural extracts play an important role in traditional medicines for the treatment of diabetes mellitus and are also an essential resource for new drug discovery. Dipeptidyl peptidase IV (DPP-IV) inhibitors are potential candidates for the treatment of type 2 diabetes mellitus, and the effectiveness of certain antidiabetic extracts of natural origin could be, at least partially, explained by the inhibition of DPP-IV. METHODOLOGY/PRINCIPAL FINDINGS: Using an initial set of 29,779 natural products that are annotated with their natural source and an experimentally validated virtual screening procedure previously developed in our lab (Guasch et al.; 2012) [1], we have predicted 12 potential DPP-IV inhibitors from 12 different plant extracts that are known to have antidiabetic activity. Seven of these molecules are identical or similar to molecules with described antidiabetic activity (although their role as DPP-IV inhibitors has not been suggested as an explanation for their bioactivity). Therefore, it is plausible that these 12 molecules could be responsible, at least in part, for the antidiabetic activity of these extracts through their inhibitory effect on DPP-IV. In addition, we also identified as potential DPP-IV inhibitors 6 molecules from 6 different plants with no described antidiabetic activity but that share the same genus as plants with known antidiabetic properties. Moreover, none of the 18 molecules that we predicted as DPP-IV inhibitors exhibits chemical similarity with a group of 2,342 known DPP-IV inhibitors. CONCLUSIONS/SIGNIFICANCE: Our study identified 18 potential DPP-IV inhibitors in 18 different plant extracts (12 of these plants have known antidiabetic properties, whereas, for the remaining 6, antidiabetic activity has been reported for other plant species from the same genus). Moreover, none of the 18 molecules exhibits chemical similarity with a large group of known DPP-IV inhibitors.

Identification of novel human dipeptidyl peptidase-IV inhibitors of natural origin (part I): virtual screening and activity assays.

BACKGROUND: There has been great interest in determining whether natural products show biological activity toward protein targets of pharmacological relevance. One target of particular interest is DPP-IV whose most important substrates are incretins that, among other beneficial effects, stimulates insulin biosynthesis and secretion. Incretins have very short half-lives because of their rapid degradation by DPP-IV and, therefore, inhibiting this enzyme improves glucose homeostasis. As a result, DPP-IV inhibitors are of considerable interest to the pharmaceutical industry. The main goals of this study were (a) to develop a virtual screening process to identify potential DPP-IV inhibitors of natural origin; (b) to evaluate the reliability of our virtual-screening protocol by experimentally testing the in vitro activity of selected natural-product hits; and (c) to use the most active hit for predicting derivatives with higher binding affinities for the DPP-IV binding site. METHODOLOGY/PRINCIPAL FINDINGS: We predicted that 446 out of the 89,165 molecules present in the natural products subset of the ZINC database would inhibit DPP-IV with good ADMET properties. Notably, when these 446 molecules were merged with 2,342 known DPP-IV inhibitors and the resulting set was classified into 50 clusters according to chemical similarity, there were 12 clusters that contained only natural products for which no DPP-IV inhibitory activity has been previously reported. Nine molecules from 7 of these 12 clusters were then selected for in vitro activity testing and 7 out of the 9 molecules were shown to inhibit DPP-IV (where the remaining two molecules could not be solubilized, preventing the evaluation of their DPP-IV inhibitory activity). Then, the hit with the highest activity was used as a lead compound in the prediction of more potent derivatives. CONCLUSIONS/SIGNIFICANCE: We have demonstrated that our virtual-screening protocol was successful in identifying novel lead compounds for developing more potent DPP-IV inhibitors.

The oceanic biological pump modulates the atmospheric transport of persistent organic pollutants to the Arctic.

Semivolatile persistent organic pollutants have the potential to reach remote environments, such as the Arctic Ocean, through atmospheric transport and deposition. Here we show that this transport of polychlorinated biphenyls to the Arctic Ocean is strongly retarded by the oceanic biological pump. A simultaneous sampling of atmospheric, seawater and plankton samples was performed in July 2007 in the Greenland Current and Atlantic sector of the Arctic Ocean. The atmospheric concentrations declined during atmospheric transport over the Greenland Current with estimated half-lives of 1-4 days. These short half-lives can be explained by the high air-to-water net diffusive flux, which is similar in magnitude to the estimated settling fluxes in the water column. Therefore, the decrease of atmospheric concentrations is due to sequestration of atmospheric polychlorinated biphenyls by enhanced air-water diffusive fluxes driven by phytoplankton uptake and organic carbon settling fluxes (biological pump).

Ubiquitous net volatilization of polycyclic aromatic hydrocarbons from soils and parameters influencing their soil-air partitioning.

Soils are a major reservoir of organic pollutants, and soil-air partitioning and exchange are key processes controlling the regional fate of pollutants. Here, we report and discuss the soil concentrations of polycyclic aromatic hydrocarbons (PAHs), their soil fugacities, the soil-air partition coefficients (K(SA)) and soil-air gradients for rural and semirural soils, in background areas of N-NE Spain and N-NW England. Different sampling campaigns were carried out to assess seasonal variability and differences between sampling sites. K(SA) values were dependent on soil temperature and soil organic quantity and type. Soil fugacities of phenanthrene and its alkyl homologues were 1-2 orders of magnitude higher than their ambient air fugacities for all sampling sites and periods. The soil to air fugacity ratio was correlated with soil temperature and soil redox potential. Similar trends for other PAHs were found but with lower fugacity ratios. The ubiquitous source of PAHs from background soils to the atmosphere found in all temperate regions in different seasons provides an indirect evidence of potential in situ generation of two to four ring PAHs and their alkyl homologues in the surface soil. We discuss this hypothetical biogenic source and other potential processes that could drive the high soil to air fugacity ratios of some PAHs.

Factors influencing the soil-air partitioning and the strength of soils as a secondary source of polychlorinated biphenyls to the atmosphere.

Soils are a major reservoir of persistent organic pollutants, and soil-air partitioning and exchange are key processes controlling the atmospheric concentrations and regional fate of pollutants. Here, we report and discuss the concentrations of polychlorinated biphenyls (PCBs) in soils, their measured fugacities in soil, the soil-air partition coefficients (K(SA)) and soil-air fugacity gradients in rural background areas of N-NE Spain and N-NW England. Four sampling campaigns were carried out to assess seasonal and daily variability and differences between sampling sites. K(SA) values were significantly dependent on soil temperature and soil organic matter quantity, and to a minor extent organic matter type. All the PCB congeners in the soil are close to equilibrium with the atmosphere at rural Ebro sites, but soil fugacities tend to be higher than ambient air fugacities in early and late summer, consistent with the influence of temperature on soil-air partitioning. Therefore, during warm periods, soils increment their strength as secondary sources to the atmosphere. The mixture of PCBs found in the atmosphere is clearly strongly influenced by the mixture of PCBs which escape from soil, with significant correlations between them (R(2) ranging between 0.35 and 0.74 and p-level <0.001 for the Ebro sampling sites). Conversely, the close-to-equilibrium to net sink status of rural UK sites, suggest a close coupling of air and soil concentrations, but it is not possible to elucidate the importance of these soils as secondary sources yet, and presumably there are still significant primary sources to the regional/global environment.

Persistent organic pollutants in Mediterranean seawater and processes affecting their accumulation in plankton.

The Mediterranean and Black Seas are unique marine environments subject to important anthropogenic pressures due to riverine and atmospheric inputs of organic pollutants. Here, we report the results obtained during two east-west sampling cruises in June 2006 and May 2007 from Barcelona to Istanbul and Alexandria, respectively, where water and plankton samples were collected simultaneously. Both matrixes were analyzed for hexaclorochyclohexanes (HCHs), hexachlorobenzene (HCB), and 41 polychlorinated biphenyl (PCB) congeners. The comparison of the measured HCB and HCHs concentrations with previously reported dissolved phase concentrations suggests a temporal decline in their concentrations since the 1990s. On the contrary, PCB seawater concentrations did not exhibit such a decline, but show a significant spatial variability in dissolved concentrations with lower levels in the open Western and South Eastern Mediterranean, and higher concentrations in the Black, Marmara, and Aegean Seas and Sicilian Strait. PCB and OCPs (organochlorine pesticides) concentrations in plankton were higher at lower plankton biomass, but the intensity of this trend depended on the compound hydrophobicity (K(OW)). For the more persistent PCBs and HCB, the observed dependence of POP concentrations in plankton versus biomass can be explained by interactions between air-water exchange, particle settling, and/or bioaccumulation processes, whereas degradation processes occurring in the photic zone drive the trends shown by the more labile HCHs. The results presented here provide clear evidence of the important physical and biogeochemical controls on POP occurrence in the marine environment.