High sporulation and overexpression of virulence factors in biofilms and reduced susceptibility to vancomycin and linezolid in recurrent Clostridium [Clostridioides] difficile infection isolates

Clostridium [Clostridioides] difficile infection (CDI) is one of the leading causes of diarrhea associated with medical care worldwide, and up to 60% of patients with CDI can develop a recurrent infection (R-CDI). A multi-species microbiota biofilm model of C. difficile was designed to evaluate the differences in the production of biofilms, sporulation, susceptibility to drugs, expression of sporulating (sigH, spo0A), quorum sensing (agrD1, and luxS), and adhesion-associated (slpA and cwp84) pathway genes between selected C. difficile isolates from R-CDI and non-recurrent patients (NR-CDI). We obtained 102 C. difficile isolates from 254 patients with confirmed CDI (66 from NR-CDI and 36 from R-CDI). Most of the isolates were biofilm producers, and most of the strains were ribotype 027 (81.374%, 83/102). Most C. difficile isolates were producers of biofilm (100/102), and most were strongly adherent. Sporulation was higher in the R-CDI than in the NR-CDI isolates (p = 0.015). The isolates from R-CDI patients more frequently demonstrated reduced susceptibility to vancomycin than isolates of NR-CDI patients (27.78% [10/36] and 9.09% [6/66], respectively, p = 0.013). The minimum inhibitory concentrations for vancomycin and linezolid against biofilms (BMIC) were up to 100 times and 20 times higher, respectively, than the corresponding planktonic MICs. Expression of sigH, spo0A, cwp84, and agrD1 was higher in R-CDI than in NR-CDI isolates. Most of the C. difficile isolates were producers of biofilms with no correlation with the ribotype. Sporulation was greater in R-CDI than in NR-CDI isolates in the biofilm model of C. difficile. The R-CDI isolates more frequently demonstrated reduced susceptibility to vancomycin and linezolid than the NR-CDI isolates in both planktonic cells and biofilm isolates. A higher expression of sporulating pathway (sigH, spo0A), quorum sensing (agrD1), and adhesion-associated (cwp84) genes was found in R-CDI than in NR-CDI isolates. All of these factors can have effect on the recurrence of the infection.Peer reviewe

Living Situation and Physical Activity in the COVID-19 Pandemic Among Private University Students

Physical activity levels among college students in private institutions were significantly altered by the COVID-19 pandemic. With COVID-19’s impact on universities, many students experienced transition, including a change in living situation. Behaviors in college help establish life-long habits that can determine health outcomes, so it’s important to investigate any declines in physical activity observed during the pandemic. PURPOSE: The purpose of this study was to assess differences in physical activity based on living situation among 18- to 25-year-old private university students during the COVID-19 pandemic. METHODS: Adults (n=109) between 18- and 25-years-old in the greater Houston area completed an online survey, which included the International Physical Activity Questionnaire – Short Form. Independent samples T-tests examined MET-minute differences based on living situation. RESULTS: Students living with versus without a parent/guardian attained similar activity levels (t(107) = -.114, p = .910) before the pandemic, but students living with a parent/guardian engaged in significantly less activity (t(107) = 2.04, p = .044) during the pandemic. CONCLUSION: The pandemic presented a strong obstacle to physical activity participation among private university students. Students living with a parent/guardian during this time saw an even more significant decrease in physical activity. Based on these findings, targeted interventions should be made to increase the physical activity of college students during COVID-19, especially for those living at home with a parent or guardian

Living Situation and Physical Activity in the COVID-19 Pandemic Among American Private University Students

International Journal of Exercise Science 15(4): 1064-1074, 2022. Many university students experienced changes during the COVID-19 pandemic, including potential changes in physical activity (PA) levels and living situation. As PA behaviors in young adulthood help establish life-long habits and future health outcomes, the purpose of this study was to investigate overall change in PA, as well as change in PA due to living situation, among private university students during the COVID-19 pandemic. Private university students (n = 109) between 18 and 25 years of age completed an online survey that included the International Physical Activity Questionnaire – Short Form. T-tests examined changes in overall time spent in PA from before to during the COVID-19 pandemic, and the differences in MET-minute distributions between groups. Students performed significantly less activity during the COVID-19 pandemic than before (t(108) = 3.51, p = .001, d = 0.493), with 70.6% of all students meeting exercise recommendations before the pandemic and 51.4% after. Students living with vs. without a parent/guardian attained similar PA levels (t(107) = -.114, p = .910) before the pandemic (73.1% vs. 69.9%, respectively), but students living with a parent/guardian engaged in significantly less PA (t(107) = 2.04, p = .044, d = 0.475) than those living without a parent/guardian during the pandemic (37.5% vs. 57.1%, respectively). The declines in PA suggest the need for targeted interventions and education among private university students. In order to maximize the health benefits of PA, it is crucial that activity engagement return to at least pre-COVID-19 levels

Circulation of Highly Drug-Resistant Clostridium difficile Ribotypes 027 and 001 in Two Tertiary-Care Hospitals in Mexico

© 2018, Mary Ann Liebert, Inc.OBJECTIVE: To assess drug susceptibility and characterize Clostridium difficile ribotypes in isolates from two tertiary-care hospitals in Mexico. METHODS: Isolates were evaluated for genotyping, antimicrobial susceptibility testing and detection of mutations associated with drug resistance. PCR ribotyping was performed using a combination of gel-based and capillary electrophoresis-based approaches. RESULTS: MIC50 and MIC90 were ≥128 mg/L for ciprofloxacin, erythromycin, clindamycin, and rifampicin. There was no reduced susceptibility to metronidazole or tetracycline; however, reduced susceptibility to vancomycin (≥4 mg/L) and fidaxomicin (≥2 mg/L) was detected in 50 (40.3%) and 4 (3.2%) isolates, respectively. Furthermore, the rpoB Arg505Lys mutation was more frequently detected in isolates with high minimum inhibitory concentration (MIC) to rifampicin (≥32 mg/L) (OR = 52.5; 95% CI = 5.17-532.6; p < 0.000). Of the 124 C. difficile isolates recovered, 84 (66.7%) were of ribotype 027, 18 (14.5%) of ribotype 001, and the remainder were other ribotypes (353, 255, 220, 208, 176, 106, 076, 020, 019, 017, 014, 012, 003, and 002). CONCLUSION: Ribotypes 027 and 001 were the most frequent C. difficile isolates recovered in this study, and demonstrated higher MICs. Furthermore, we found four isolates with reduced susceptibility to fidaxomicin, raising a concern since this drug is currently unavailable in Mexican Hospitals.Peer reviewedFinal Accepted Versio

Are you drowned in microplastic pollution? A brief insight on the current knowledge for early career researchers developing novel remediation strategies

Microplastics (MPs) composed of different polymers with various shapes, within a vast granulometric distribution (1&nbsp;μm - 5&nbsp;mm) and with a wide variety of physicochemical surface and bulk characteristics spiral around the globe, with different atmospheric, oceanic, cryospheric, and terrestrial residence times, while interacting with other pollutants and biota. The challenges of microplastic pollution are related to the complex relationships between the microplastic generation mechanisms (physical, chemical, and biological), their physicochemical properties, their interactions with other pollutants and microorganisms, the changes in their properties with aging, and their small sizes that facilitate their diffusion and transportation between the air, water, land, and biota, thereby promoting their ubiquity. Early career researchers (ERCs) constitute an essential part of the scientific community committed to overcoming the challenges of microplastic pollution with their new ideas and innovative scientific perspectives for the development of remediation technologies. However, because of the enormous amount of scientific information available, it may be difficult for ERCs to determine the complexity of this environmental issue. This mini-review aims to provide a quick and updated overview of the essential insights of microplastic pollution to ERCs to help them acquire the background needed to develop highly innovative physical, chemical, and biological remediation technologies, as well as valorization proposals and environmental education and awareness campaigns. Moreover, the recommendations for the development of holistic microplastic pollution remediation strategies presented here can help ERCs propose technologies considering the environmental, social, and practical dimensions of microplastic pollution while fulfilling the current government policies to manage this plastic waste

Análisis de los espectros de absorción de las películas radiocrómicas EBT2 y EBT3

Objetivo: Analizar los espectros de absorción neta de las películas radiocrómicas EBT2 y EBT3 para describir su influencia en el comportamiento de las curvas de dosis-respuesta. Metodología: Las películas se irradiaron en un acelerador lineal de 6 MV. La obtención de los espectros de absorción neta se realizó con espectrofotómetro UV/VIS. Las curvas de dosis-respuesta se obtuvieron con un escáner, un láser He-Ne y un espectrofotómetro. Resultados: El espectro de absorción de las EBT2 muestra tres bandas de absorción centradas que conservan la posición y aumentan su intensidad en función de la dosis, sin embargo, este comportamiento no se observa en las películas EBT3. La curva dosis-respuesta muestra la máxima sensibilidad utilizando el espectrofotómetro, pero no muestra un comportamiento definido. Implicaciones: Generación de nuevos conocimientos para la creación de nuevos sistemas ópticos capaces de amplificar la sensibilidad de la respuesta de las películas. Originalidad: Mostrar la correlación entre los espectros de absorción neta y su influencia en las curvas dosis-respuesta en tres diferentes sistemas ópticos. Conclusiones: El comportamiento de los espectros de absorción aunado al comportamiento de las curvas dosis-respuesta nos ayuda a descartar el uso de sistemas ópticos que no garanticen un uso clínico confiable

Clinical characteristics associated with the severity of Clostridium [Clostridioides] difficile infection in a tertiary teaching hospital from Mexico

Background: Clostridium difficile infection (CDI) is a leading cause of healthcare-associated diarrhea worldwide. In this study, risk factors associated with the development of severe-complicated and recurrent outcomes in CDI patients in different age groups, including the non-elderly, were assessed in a third-level hospital. Methods: CDI cases were detected by clinical data and polymerase-chain-reaction (PCR). Clinical, demographic, epidemiological, and microbiological risk factors for CDI were evaluated. Results: During the study period, 248 out of 805 patients with nosocomial diarrhea were diagnosed with CDI and the majority were severe-complicated cases (87.90%). Female gender (OR 3.19, 95% CI 1.19e8.55, p ¼ 0.02) and lymphoma (OR 3.95, 95% CI 1.03e15.13, p ¼ 0.04) were risk factors for severe-complicated CDI. Mature adulthood (51e60 years) (OR 5.80, 95% CI 1.56e21.62, p ¼ 0.01), previous rifampicin use (OR 7.44, 95% CI 2.10e26.44, p ¼ 0.00), and neoplasm (solid malignant neoplasm or hematological malignancies) (OR 4.12, 95% CI 1.01e16.83, p ¼ 0.04) were risk factors for recurrent infection. Autoimmune disorders (OR 6.62, CI 95% 1.26e34.73, p ¼ 0.02), leukemia (OR 4.97, 95% CI 1.05e23.58, p ¼ 0.04), lymphoma (OR 3.79, 95% CI 1.03e12.07, p ¼ 0.04) and previous colistin treatment (OR 4.97, 95% CI 1.05e23.58, p ¼ 0.04) were risk factors for 30-day mortality. Conclusion: Newly identified risk factors for recurrent CDI were rifampicin treatment and age between 51 and 60 years; colistin treatment was identified as a risk factor for 30-day mortality. Previously identified risk factors for severe-complicated CDI were confirmed, but with a major impact on non-elderly patients

Microvertebrates preserved in mammal burrows from the Holocene of the Argentine Pampas: a taphonomic and paleoecological approach

Microvertebrates are a major component of many assemblages recovered from the Quaternary of the Argentine Pampas. The main goal of this paper is to analyse the taphonomic history of a Holocene microfossil bonebed, recovered from the infilling of a burrow. Evidences suggest the plains vizcacha Lagostomus maximus as the putative producer of the burrow. The assemblage includes individuals belonging to different taxa of mammals (marsupials and rodents) and reptiles (snakes). Taphonomic features suggest that the accumulation inside the burrow was related to flooding processes in the plain. The burrow was a natural trap that favoured the accumulation and preservation of remains corresponding to individuals from different sources. According to the taphonomic evidence, some individuals (Lagostomus maximus, Lestodelphys halli and Serpentes indet.) died inside the burrow, whereas others (Microcavia australis, Reithrodon auritus and Ctenomys sp.) died outside the burrow, and after a time of being exposed on the surface their remains were transported by surface run-offs into the burrow. The record of Lestodelphys halli and Serpentes indet. in the burrow produced by Lagostomus maximus could be related to a circumstantial use. Mammal burrows are a significant taphonomic mode for the late Cenozoic of the Argentine Pampas

Planeación, gobernanza y sustentabilidad Retos y desafíos desde el enfoque territorial

Frente a la compleja realidad actual, resulta ineludible el desarrollo de la investigación científica de los fenómenos y procesos urbanos, territoriales y ambientales, que contribuya a su comprensión y la construcción de alternativas de solución a los retos y desafíos vigentes. En este contexto, el abordaje de las ciudades y regiones metropolitanas, el ordenamiento del territorio y la ocupación del espacio, así como la relación sociedad-naturaleza y la complejidad ambiental, precisa la generación de metodologías y procesos de investigación multi e inter disciplinarios que contribuyan a la comprensión de los procesos socioterritoriales, el mejoramiento de las condiciones de vida y la conservación ambiental.Programa de Fortalecimiento de la Calidad Educativa PFCE-2016 proyecto K0313101