Assessing Diesel Tolerance of Chromobacterium violaceum: Insights from Growth Kinetics, Substrate Utilization, and Implications for Microbial Adaptation.

This study aimed to determine the tolerance of Chromobacterium violaceum ATCC 12472 to diesel. The growth of the strain was evaluated through exposure to various diesel concentrations (1, 2.5, 5, 7.5, and 10% v/v), with continuous monitoring of growth via optical density measurements until the death phase was reached. Employing a logistic model, we analyzed the growth kinetics of C. violaceum and compared them with five other models to comprehend substrate utilization dynamics. Our results indicate that optimal bacterial growth occurred at 2.5% (v/v) or 18,125 mg/L diesel, while both higher and lower concentrations manifested inhibitory and increasingly stressful effects. The Aiba model emerged as the most fitting representation of substrate utilization by C. violaceum. In addition, our findings underscore the remarkable diesel tolerance of C. violaceum ATCC 12472, despite the inherently stressful nature of the medium. This study contributes to the understanding of microbial responses to environmental stressors and highlights the pivotal role of the substrate concentration in influencing microbial growth. These insights have implications for bioremediation strategies and enhance our understanding of bacterial ecological resilience in the presence of hydrocarbon pollutants.

Persistent colonization of Candida auris among inpatients rescreened as part of a weekly surveillance program.

We established a surveillance program to evaluate persistence of C. auris colonization among hospitalized patients. Overall, 17 patients (34%) had ≥1 negative result followed by a positive test, and 7 (41%) of these patients had ≥2 consecutive negative tests.

Operational impact of decreased turnaround times for Candida auris screening tests in a tertiary academic medical center.

Objective: Assess turnaround time (TAT) and cost-benefit of on-site C. auris screening and its impact on length of stay (LOS) and costs compared to reference laboratories. Design: Before-and-after retrospective cohort study. Setting: Large-tertiary medical center. Methods: We validated an on-site polymerase chain reaction-based testing platform for C. auris and retrospectively reviewed hospitalized adults who screened negative before and after platform implementation. We constructed multivariable models to assess the association of screening negative with hospital LOS/cost in the pre and postimplementation periods. We adjusted for confounders such as demographics and indwelling device use, and compared TATs for all samples tested. Results: The sensitivity and specificity of the testing platform were 100% and 98.11%, respectively, compared to send-out testing. The clinical cohort included 287 adults in the pre and 1,266 postimplementation period. The TAT was reduced by more than 2 days (3 (interquartile range (IQR): 2.0, 7.0) vs 0.42 (IQR: 0.24, 0.81), p < 0.001). Median LOS was significantly lower in the postimplementation period; however, this was no longer evident after adjustment. In relation to total cost, the time period had an effect of $6,965 (95% CI: -$481, $14,412); p = 0.067) on reducing the cost. The median adjusted total cost per patient was $7,045 (IQR: $3,805, $13,924) less in the post vs the preimplementation period. Conclusions: Our assessment did not find a statistically significant change in LOS, nevertheless, on-site testing was not cost-prohibitive for the institution. The value of on-site testing may be supported if an institutional C. auris reduction strategy emphasizes faster TATs.

Detection of the clinically persistent, pathogenic yeast spp. Candida auris from hospital and municipal wastewater in Miami-Dade County, Florida.

The use of wastewater-based surveillance (WBS) for detecting pathogens within communities has been growing since the beginning of the COVID-19 pandemic with early efforts investigating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA in wastewater. Recent efforts have shed light on the utilization of WBS for alternative targets, such as fungal pathogens, like Candida auris, in efforts to expand the technology to assess non-viral targets. The objective of this study was to extend workflows developed for SARS-CoV-2 quantification to evaluate whether C. auris can be recovered from wastewater, inclusive of effluent from a wastewater treatment plant (WWTP) and from a hospital with known numbers of patients colonized with C. auris. Measurements of C. auris in wastewater focused on culture-based methods and quantitative PCR (qPCR). Results showed that C. auris can be cultured from wastewater and that levels detected by qPCR were higher in the hospital wastewater compared to the wastewater from the WWTP, suggesting either dilution or degradation of this pathogenic yeast at downstream collection points. The results from this study illustrate that WBS can extend beyond SARS-CoV-2 monitoring to evaluate additional non-viral pathogenic targets and demonstrates that C. auris isolated from wastewater is competent to replicate in vitro using fungal-specific culture media.

Are 150 km of open sea enough? Gene flow and population differentiation in a bat-pollinated columnar cactus.

Genetic differentiations and phylogeographical patterns are controlled by the interplay between spatial isolation and gene flow. To assess the extent of gene flow across an oceanic barrier, we explored the effect of the separation of the peninsula of Baja California on the evolution of mainland and peninsular populations of the long-lived columnar cactus Stenocereus thurberi. We analyzed twelve populations throughout the OPC distribution range to assess genetic diversity and structure using chloroplast DNA sequences. Genetic diversity was higher (Hd = 0.81), and genetic structure was lower (GST = 0.143) in mainland populations vs peninsular populations (Hd = 0.71, GST = 0.358 respectively). Genetic diversity was negatively associated with elevation but positively with rainfall. Two mainland and one peninsular ancestral haplotypes were reconstructed. Peninsular populations were as isolated among them as with mainland populations. Peninsular haplotypes formed a group with one mainland coastal population, and populations across the gulf shared common haplotypes giving support to regular gene flow across the Gulf. Gene flow is likely mediated by bats, the main pollinators and seed dispersers. Niche modeling suggests that during the Last Glacial Maximum (c. 130 ka), OPC populations shrank to southern locations. Currently, Stenocereus thurberi populations are expanding, and the species is under population divergence despite ongoing gene flow. Ancestral populations are located on the mainland and although vicariant peninsular populations cannot be ruled out, they are likely the result of gene flow across the seemingly formidable barrier of the Gulf of California. Still, unique haplotypes occur in the peninsula and the mainland, and peninsular populations are more structured than those on the mainland.

Prevalencia de medicamentos que prolongan el intervalo QT en salas de cardiología de un hospital de alta complejidad / Drug induced prolongation of Q-T interval in cardiology wards

Resumen: Antecedentes: La prevalencia del síndrome del QT largo (SQTL) producido por medicamentos es una de las reacciones adversas que en el último tiempo ha aumentado en prevalencia y mortalidad. No solamente ocurre con el uso de medicamentos para el tratamiento de cardiopatías, sino también en medicamentos con otra acción terapéutica. Objetivo: Evaluar la prevalencia del síndrome del SQTL inducido por medicamentos en salas de cardiología de un hospital de alta complejidad. Métodos: Estudio prospectivo, de tipo descriptivo y de corte transversal en 36 pacientes cardiópatas, que consistió en evaluar la frecuencia del uso de medicamentos que son capaces de producir un SQTL y la prevalencia de este efecto adverso. Los datos clínicos se recolectaron de la ficha clínica y de entrevistas con los pacientes. Se efectuó un seguimiento para detectar la aparición de prolongación del intervalo QT. Los resultados obtenidos fueron presentados por medio de estadística descriptiva (programa estadístico Statgraphics Centurion, versión XVI). No hubo estadística inferencial dada la ausencia de un grupo control. Resultados: 41,7%, de los 36 pacientes presentaron SQTL que en 86,7% de ellos fue asociado a un medicamento. Los medicamentos más frecuentemente asociados a este efecto adverso fueron Amiodarona (38,5%) y Ondansetrón (23,1%), y el factor de riesgo mayormente involucrado fue el sexo femenino (61,5%). Conclusión: Existió una alta prevalencia del uso de medicamentos que producen un SQTL, destacándose que existen medicamentos utilizados para otras patologías que también pueden producirlo.

Abstract: Background: The prevalence of the Long QT interval syndrome (LQTS) associated to drugs has increased en the last decades along with an increased mortality due to this condition. It occurs not only with drugs used to treat cardiac disease but also to other drugs. Aim: To evaluate the prevalence of drug induced LQTS in cardiology wards of a high complexity hospital. Method: This is a prospective, descriptive and cross sectional study in 36 patients with heart disease. The use of drugs known to affect the QT interval along with the frequency of LGTS were evaluated. Clincal data was obtained from clinical records and personal interviews. Patients were followed for the appearance of LQTS. Descriptive were used to present the results. No inferential statistics were used as no control group was involved (Statgraphics Centurion, version XVI). Results: 41.7% of the 36 patients developed LQTS and the association with drugs was present in 86.7% of them. The drugs most commonly identified were amiodarone (38.5%) and ondansetron (23.1%) of patients. Female geneder was the most common associated condition (61.5%). Conclusion: There was a frequent use of drugs known to produce LQTS, but other drugs may also be associated int this group of patients with heart disease admitted to intensive or intermediate care facilities.

Bloodstream Infection Risk, Incidence, and Deaths for Hospitalized Patients during Coronavirus Disease Pandemic.

Hospital-acquired infections are emerging major concurrent conditions during the coronavirus disease (COVID-19) pandemic. We conducted a retrospective review of hospitalizations during March‒October 2020 of adults tested by reverse transcription PCR for severe acute respiratory syndrome coronavirus 2. We evaluated associations of COVID-19 diagnosis with risk for laboratory-confirmed bloodstream infections (LCBIs, primary outcome), time to LCBI, and risk for death by using logistic and competing risks regression with adjustment for relevant covariates. A total of 10,848 patients were included in the analysis: 918 (8.5%) were given a diagnosis of COVID-19, and 232 (2.1%) had LCBIs during their hospitalization. Of these patients, 58 (25%) were classified as having central line‒associated bloodstream infections. After adjusting for covariates, COVID-19‒positive status was associated with higher risk for LCBI and death. Reinforcement of infection control practices should be implemented in COVID-19 wards, and review of superiority and inferiority ranking methods by National Healthcare Safety Network criteria might be needed.

Candida auris Invasive Infections during a COVID-19 Case Surge.

Clinical cases of C. auris noted during a COVID-19 surge led to an epidemiological, clinical, and genomic investigation. Evaluation identified a close genetic relationship but inconclusive epidemiologic link between all cases. Prolonged hospitalization due to critical illness from COVID-19 and use of antimicrobials may have contributed to clinical infections.

Pseudodextrocardia: una nueva defifinición / Pseudo-dextrocardia: a new defifinition

La pseudodextrocardia se ha definido como un desplazamiento irregular del corazón y sus estructuras vasculares hacia la derecha por causas extracardiacas. Es un hallazgo ocasional en estudios imagenológicos de tórax o abdomen y varía acorde con las diferentes relaciones causales. Se presenta el caso de un paciente con una neumopatía crónica, quien a su ingreso presenta pseudodextrocardia como hallazgo incidental.

Pseudo-dextrocardia has been defined as an unusual displacement of the heart and its vascular structures to the right secondary to extracardiac causes. It is an occasional finding in thoracic or abdominal imaging studies and varies according to the various causal relationships. We report a case of pseudo-dextrocardia as an incidental finding in a patient admitted with chronic pulmonary disease.

Research on heart failure in Colombia 1980-2015: a systematic review / La investigación en falla cardíaca en Colombia 1980-2015: una revisión sistemática

Abstract Introduction: Heart failure is one of the most prevalent diseases worldwide. In Colombia, the state of research on the subject is unknown. Objective: To describe the original publications on heart failure in Colombia. Materials and methods: Systematic review. Digital search in Embase, PubMed, LILACS and Scielo, using the MeSH terms: "heart failure", "Colombian", "Colombia", "Latin America", "developing countries". Manual search of 58 journals identified in Publindex. Original research that evaluated adult Colombians with heart failure and published between 1980 and 2015 were included. Results: 2 684 articles were identified, of which 35 met the inclusion criteria. 30 (85.7%) were published since 2009, 30 (85.7%) were conducted in Bogotá and Medellín, 11 (31.4%) had n>200, 19 (54.2%) were descriptive and 5 (14.2%) quasi-experimental. Moreover, 9 (25.7%) described general populations, 9 (25.7%) addressed the issue of self-care, 3 (8.8%) cardiac rehabilitation, 3 (8.8%) perception of the disease and 3 (8.8%) prognostic factors. Conclusions: The amount of published original research on heart failure is low, and most of them were carried out recently. Descriptive design was the most frequent, while the most frequently addressed topics were self-care and population descriptions.

Resumen Introducción. La falla cardíaca es una de las enfermedades con mayor prevalencia a nivel mundial. En Colombia no se conoce con certeza el estado de la investigación en torno al tema. Objetivo. Describir las publicaciones originales en falla cardíaca en Colombia. Materiales y métodos. Revisión sistemática. Búsqueda electrónica en Embase, PubMed, LILACS Y SciELO, con términos MeSH: "heart failure", "colombian", "Colombia", "Latin America", "developing countries". Búsqueda manual en 58 revistas identificadas en Publindex. Se incluyeron investigaciones originales, publicadas entre 1980 y 2015, que evaluaron población adulta colombiana con falla cardíaca. Resultados. Se identificaron 2 684 artículos: 35 cumplieron criterios de inclusión; 30 (85.7%) fueron publicados a partir del 2009; 30 (85.7%) se realizaron en Bogotá y Medellín; 11 (31.4%) tuvieron n>200; 19 (54.2%) fueron descriptivos y 5 (14.2%) cuasiexperimentales; 9 (25.7%) describieron poblaciones generales; 9 (25.7%) abordaron el tema del autocuidado, 3 (8.8%), la rehabilitación cardíaca, 3 (8.8%), la percepción de enfermedad y 3 (8.8%), los factores pronósticos. Conclusión. El número de investigaciones originales publicadas sobre falla cardíaca es escaso; la mayoría se realizó en los últimos años. El diseño descriptivo fue el más común. Los temas abordados con mayor frecuencia fueron el autocuidado y las descripciones poblacionales.

Didácticas innovadoras en el aprendizaje de la farmacología en estudiantes de medicina / Innovative teaching in pharmacology learning for medicine students

Introducción: la farmacología tiene alta relevancia en la formación del médico. Las clases expositivas son poco motivadoras para los estudiantes; esto ha llevado a incluir estrategias que despierten interés. Material y métodos: descripción de didácticas para apoyar el aprendizaje de la farmacología en tutorías por pares estudiantes (Caso clínico, Cubo mágico, Stop, Crucigrama, Parejas perfectas, Memoria al límite, Encapsúlate, Ritmo y fila, Ruleta, Sopa de letras, Cadeneta, Mapa conceptual y debate, Concéntrese). Se aplicó una encuesta semiestructurada para explorar la percepción de los estudiantes respecto de las tutorías. Resultados: la encuesta semiestructurada se aplicó a 37 estudiantes. El 65% está totalmente de acuerdo en que la asistencia a las monitorías de farmacología contribuye de manera positiva a su aprendizaje. El 40,5% refirió que las tutorías apoyan la obtención de un resultado favorable para la aprobación de la asignatura. El 62% manifestó la utilidad de las tutorías para definir los medicamentos que se usarán en el paciente. El 72,9% recomendaría a sus compañeros asistir a las tutorías. Entre el 24,3 y 48,6%, según la didáctica de aprendizaje, consideró que estas son excelentes. Discusión: se describe la experiencia del uso de didácticas que apoyan el aprendizaje de la farmacología, basadas en actividades lúdicas, promoviendo el aprendizaje significativo de la farmacología. En las tutorías con pares, los estudiantes se sienten en mayor confianza, participan activamente, lo que genera un ambiente que facilita el aprendizaje. Los estudiantes asistentes a las tutorías de farmacología refieren que hay empatía habitualmente con los tutores durante las sesiones. (AU)

Introduction: pharmacology is fundamental in the medical training. As theoretical classes hardly motivate students. This has led to include strategies that arouse interest. Methods: class syllabus, partnership working and informal activities by student tutors (clinical cases, crosswords, "cubo mágico", "stop", "parejas perfectas", "memoria al límite", "encápsulate", "ritmo y fila", "ruleta", "sopa de letras", "cadeneta", "concentrese" and brain storming) were sed in tutoring classes to help students in the pharmacology learning process. Questionnaires were used to collect feedback from students about tutorials. Results: the questionnaire was given to 37 students. 65% of them agreed on the positive impact the classes had on their learning; 40.5% found positive correlation between the tutoring classes and finals results; 62% referred that tutoring classes helped them defining how to match symptoms and drugs; 72.9% would recommend other students to attend the tutoring classes. Between 24.3% and 48.6% of the students, depending on the methods used, rated the experience as "excellent". Discussion: the experience regarding the use of new didactic methods was exposed. It encouraged students to approach pharmacology and it helped them improving their knowledge about the discipline through non-academic activities. Students reported that learning become easier during tutoring classes thanks to the informal context and informal relationship with the tutor. (AU)