Water Sorption and Structural Properties of Human Airway Mucus in Health and Muco-Obstructive Diseases.

Muco-obstructive diseases change airway mucus properties, impairing mucociliary transport and increasing the likelihood of infections. To investigate the sorption properties and nanostructures of mucus in health and disease, we investigated mucus samples from patients and cell cultures (cc) from healthy, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF) airways. Atomic force microscopy (AFM) revealed mucin monomers with typical barbell structures, where the globule to spacer volume ratio was the highest for CF mucin. Accordingly, synchrotron small-angle X-ray scattering (SAXS) revealed more pronounced scattering from CF mucin globules and suggested shorter carbohydrate side chains in CF mucin and longer side chains in COPD mucin. Quartz crystal microbalance with dissipation (QCM-D) analysis presented water sorption isotherms of the three types of human airway mucus, where, at high relative humidity, COPD mucus had the highest water content compared to cc-CF and healthy airway mucus (HAM). The higher hydration of the COPD mucus is consistent with the observation of longer side chains of the COPD mucins. At low humidity, no dehydration-induced glass transition was observed in healthy and diseased mucus, suggesting mucus remained in a rubbery state. However, in dialyzed cc-HAM, a sorption-desorption hysteresis (typically observed in the glassy state) appeared, suggesting that small molecules present in mucus suppress the glass transition.

Strategies to promote contraception use by female volunteers in Alzheimer's Prevention Initiative Autosomal-Dominant Alzheimer's Disease (API ADAD) Colombia trial.

BACKGROUND/AIMS: Including women of childbearing age in a clinical trial makes it necessary to consider two factors from a bioethical perspective: first, the lack of knowledge about the potential teratogenic effects of an investigational product, and also, the principle of justice not to exclude any population from the benefits of research. The most common way to address this issue is by requiring volunteers to use contraceptives before, during, and a few weeks after the clinical trial. This work presents all the strategies used to promote contraception use and prevent pregnancy during the Alzheimer's Prevention Initiative Autosomal-Dominant Alzheimer's Disease (API ADAD) Colombia clinical trial. Two characteristics of this trial make it of special interest for closely monitoring contraception use. One is that the trial lasted more than 7 years, and the other is that participants could be carriers of the E280A PSEN1 mutation, leading to a mild cognitive impairment as early as their late 30s. METHODS: An individual medical evaluation to select the contraception method that best fits the volunteer was carried out during the screening visit, remitting to the gynecologist when necessary. All non-surgical contraception methods were supplied by the sponsor. Staff were trained on contraception counseling, correctly dispensing contraceptive drugs to volunteers, and identifying, reporting, and following up on pregnancies. Two comprehensive educational campaigns on contraception use were performed, and the intervention included all volunteers. In addition, volunteers were asked on an annual survey to evaluate the dispensing procedure. Finally, the effectiveness of these strategies was retrospectively evaluated, comparing by extrapolation the number of pregnancies presented throughout the trial with the General Fertility Rate in Colombia. RESULTS: A total of 159 female volunteers were recruited. All strategies were implemented as planned, even during the COVID-19 contingency. Ten pregnancies occurred during the evaluation period (2015-2021). Two were planned; the rest were associated with a potential therapeutic failure or incorrect use of contraceptive methods for a contraceptive failure of 0.49% per year. Sixty percent of pregnancies led to an abortion, either miscarriage or therapeutic abortion. However, there was not enough data to associate the pregnancy outcome with the administration of the investigational product. Finally, we observed a lower fertility rate in women participating in the trial compared to the Colombian population. CONCLUSION: The lower rates of contraceptive failure and the decrease in the incidence of pregnancies in women participating in the trial compared to the Colombian population across the 7 years of evaluation suggest that the strategies used in API ADAD Colombia were adequate and effective in addressing contraception use.

Monoolein-Based Wireless Capacitive Sensor for Probing Skin Hydration.

Capacitive humidity sensors typically consist of interdigitated electrodes coated with a dielectric layer sensitive to varying relative humidity levels. Previous studies have investigated different polymeric materials that exhibit changes in conductivity in response to water vapor to design capacitive humidity sensors. However, lipid films like monoolein have not yet been integrated with humidity sensors, nor has the potential use of capacitive sensors for skin hydration measurements been fully explored. This study explores the application of monoolein-coated wireless capacitive sensors for assessing relative humidity and skin hydration, utilizing the sensitive dielectric properties of the monoolein-water system. This sensitivity hinges on the water absorption and release from the surrounding environment. Tested across various humidity levels and temperatures, these novel double functional sensors feature interdigitated electrodes covered with monoolein and show promising potential for wireless detection of skin hydration. The water uptake and rheological behavior of monoolein in response to humidity were evaluated using a quartz crystal microbalance with dissipation monitoring. The findings from these experiments suggest that the capacitance of the system is primarily influenced by the amount of water in the monoolein system, with the lyotropic or physical state of monoolein playing a secondary role. A proof-of-principle demonstration compared the sensor's performance under varying conditions to that of other commercially available skin hydration meters, affirming its effectiveness, reliability, and commercial viability.

Electrical Conduction Mechanisms in Ethyl Cellulose Films under DC and AC Electric Fields.

This work reports the dielectric behavior of the biopolymer ethyl cellulose (EC) observed from transient currents experiments under the action of a direct current (DC) electric field (~107 V/m) under vacuum conditions. The viscoelastic response of the EC was evaluated using dynamic mechanical analysis (DMA), observing a mechanical relaxation related to glass transition of around ~402 K. Furthermore, we propose a mathematical framework that describes the transient current in EC using a fractional differential equation, whose solution involves the Mittag-Leffler function. The fractional order, between 0 and 1, is related to the energy dissipation rate and the molecular mobility of the polymer. Subsequently, the conduction mechanisms are considered, on the one hand, the phenomena that occur through the polymer-electrode interface and, on the other hand, those which manifest themselves in the bulk material. Finally, alternating current (AC) conductivity measurements above the glass transition temperature (~402 K) and in a frequency domain from 20 Hz to 2 MHz were carried out, observing electrical conduction described by the segmental movements of the polymeric chains. Its electrical properties also position EC as a potential candidate for electrical, electronics, and mechatronics applications.

Effect of lung volume preservation during spontaneous breathing trial on successful extubation in patients receiving mechanical ventilation: protocol for a multicenter clinical trial.

BACKGROUND: In standard weaning from mechanical ventilation, a successful spontaneous breathing test (SBT) consisting of 30 min 8 cmH2O pressure-support ventilation (PSV8) without positive end-expiratory pressure (PEEP) is followed by extubation with continuous suctioning; however, these practices might promote derecruitment. Evidence supports the feasibility and safety of extubation without suctioning. Ultrasound can assess lung aeration and respiratory muscles. We hypothesize that weaning aiming to preserve lung volume can yield higher rates of successful extubation. METHODS: This multicenter superiority trial will randomly assign eligible patients to receive either standard weaning [SBT: 30-min PSV8 without PEEP followed by extubation with continuous suctioning] or lung-volume-preservation weaning [SBT: 30-min PSV8 + 5 cmH2O PEEP followed by extubation with positive pressure without suctioning]. We will compare the rates of successful extubation and reintubation, ICU and hospital stays, and ultrasound measurements of the volume of aerated lung (modified lung ultrasound score), diaphragm and intercostal muscle thickness, and thickening fraction before and after successful or failed SBT. Patients will be followed for 90 days after randomization. DISCUSSION: We aim to recruit a large sample of representative patients (N = 1600). Our study cannot elucidate the specific effects of PEEP during SBT and of positive pressure during extubation; the results will show the joint effects derived from the synergy of these two factors. Although universal ultrasound monitoring of lungs, diaphragm, and intercostal muscles throughout weaning is unfeasible, if derecruitment is a major cause of weaning failure, ultrasound may help clinicians decide about extubation in high-risk and borderline patients. TRIAL REGISTRATION: The Research Ethics Committee (CEIm) of the Fundació Unió Catalana d'Hospitals approved the study (CEI 22/67 and 23/26). Registered at ClinicalTrials.gov in August 2023. Identifier: NCT05526053.

Microbiological characteristics of infections in a group of colombian patients with oncological diagnosis, 2014 - 2016 / Características microbiológicas de infecciones en un grupo de colombianos con diagnóstico oncológico, 2014 - 2016

Objective: We aimed to describe the microbiological characteristics of infections in patients from an oncological center during 2.014-2.016. Methods: In this cross-sectional descriptive study, a total of 7.837 cultures corresponding to 1.216 patients were included. Microbiological and sociodemographic data were taken from cancer diagnosed patients admitted to Oncólogos de Occidente S.A. in Pereira, Armenia, Manizales and Cartago from January 2.014 to December 2.016. The bacterial resistance profiles were defined according to the CLSI guideline. Culture foci were blood, urine, tissue biopsies, skin and soft tissues, mucous membranes and feces. Results: The culture-positive rate was 27,94%. Amongst 2.190 isolates, Escherichia coli (22,42%) was the most frequent, followed by Klebsiella pneumonia (21,27%), Pseudomona aeruginosa (13,83%) and Staphylococcus aureus (5,11%). The most common mechanisms of antimicrobial resistance in Gram-negatives were Extended-Spectrum β-Lactamase (45,45%) and AmpC-type β-lactamases (37,71%). Discussion: Up to nearly one-third of our participants' cultures were positive and a vast majority were gram-negatives, provided with ESBLs or AmpCs which in oncological patients it is a catastrophic outcome. We recommend to establish antibiotic dispensing policies thus achieving a microbiological risk control and improve the epidemiological surveillance. Empirical use of beta-lactams with extended spectrum or cephalosporins of 1 to 3 generation is not recommended due to the high resistance found.

Objetivo: Describir las características microbiológicas de las infecciones en pacientes de un centro oncológico durante 2.014-2.016 Métodos: Estudio descriptivo, transversal. Incluyó 7.837 cultivos de 1.216 pacientes. Se recolectaron variables microbiológicas y sociodemográficas de pacientes diagnosticados con cáncer en las sedes de Pereira, Armenia, Manizales y Cartago de Oncólogos de Occidente S.A. durante 2.014 hasta 2.016. Los perfiles de resistencia bacteriana se definieron de acuerdo con la guía CLSI. Los focos de cultivo fueron sangre, orina, biopsias de tejidos, piel y tejidos blandos, membranas mucosas y heces. Resultados: La tasa de cultivo positivo fue del 27,94%. De 2.190 aislamientos, E. coli (22,42%) fue el más frecuente, seguido de K. pneumoniae (21,27%), P. aeruginosa (13,83%) y S. aureus (5,11%). Los principales mecanismos de resistencia identificados en Gram negativos fueron β-lactamasas de espectro extendido (45,45%) y β-lactamasa de tipo AmpC (37,71%). Discusión: Cerca de un tercio de los cultivos de los participantes fueron positivos y una vasta mayoría fueron gram negativos, provistos con ESBL o AmpC, lo que en pacientes oncológicos es un desenlace catastrófico. Recomendamos establecer políticas de dispensación de antibióticos, logrando así un control de riesgo microbiológico y mejorar la vigilancia epidemiológica. No se recomienda el uso empírico de betalactámicos con espectro extendido o cefalosporinas de 1 a 3 generación debido a la alta tasa de resistencia encontrada.

Sepsis postquirúrgica en fracturas de cadera. Estudio de dos años / Postsurgical sepsis in hip fractures. A 2-year study

Se realizó un estudio descriptivo y retrospectivo en 2 pacientes diagnosticados y tratados por sepsis posquirúrgica debido a fracturas de cadera en un período de dos años. Durante este período se realizaron 229 intervenciones quirúrgicas en dicha entidad, de ellas un 5,2 (por ciento) presentaron sepsis posquirúrgica. Se encontró la mayor incidencia de ella en pacientes del sexo femenino por encima de los 71 años de edad. Las fracturas extracapsulares predominaron significativamente. No se encontró diferencia notable entre la cirugía electiva y urgente. El tiempo quiúrgico se comportó en la mayoría de los casos entre 45 a 60 minutos. El germen que predominó fue el Stafilococus Aureus. La terapia antibiótica duró generalmente tres semanas. Se valoró el tiempo de hospitalización así como las complicaciones, las cuales se encontraron en un 25 (por ciento) de los casos

A propósito de un caso de Rhabdomiosarcoma / A propos of a case of rhabdomyosarcoma

Se describe un caso de Rhabdomiosarcoma en paciente femenina de 68 años de edad, de piel blanca, con imagen hipercaptante localizada a nivel T4