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Aquatic communities are increasingly subjected to multiple stressors through global change, including warming, pH shifts, and elevated nutrient concentrations. These stressors often surpass species tolerance range, leading to unpredictable consequences for aquatic communities and ecosystem functioning. Phytoplankton, as the foundation of the aquatic food web, play a crucial role in controlling water quality and the transfer of nutrients and energy to higher trophic levels. Despite the significance in understanding the effect of multiple stressors, further research is required to explore the combined impact of multiple stressors on phytoplankton. In this study, we used a combination of crossed experiment and mechanistic model to analyze the ecological and biogeochemical effects of global change on aquatic ecosystems and to forecast phytoplankton dynamics. We examined the effect of dust (0-75 mg L-1 ), temperature (19-27°C), and pH (6.3-7.3) on the growth rate of the algal species Scenedesmus obliquus. Furthermore, we carried out a geospatial analysis to identify regions of the planet where aquatic systems could be most affected by atmospheric dust deposition. Our mechanistic model and our empirical data show that dust exerts a positive effect on phytoplankton growth rate, broadening its thermal and pH tolerance range. Finally, our geospatial analysis identifies several high-risk areas including the highlands of the Tibetan Plateau, western United States, South America, central and southern Africa, central Australia as well as the Mediterranean region where dust-induced changes are expected to have the greatest impacts. Overall, our study shows that increasing dust storms associated with a more arid climate and land degradation can reverse the negative effects of high temperatures and low pH on phytoplankton growth, affecting the biogeochemistry of aquatic ecosystems and their role in the cycles of the elements and tolerance to global change.
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Ecossistema , Fitoplâncton , Cadeia Alimentar , Poeira , Concentração de Íons de HidrogênioRESUMO
AIM: There are limited data to evaluate hospitalization for heart failure (hHF) in non-Hispanic Black (hereafter Black) or non-Hispanic White (hereafter White) individuals without previous hHF. Our goal was to evaluate the risk of hHF among Black versus White patients with type 2 diabetes (T2DM) who were initially prescribed empagliflozin using real-world data. METHODS: This multicentre retrospective cohort study included participants aged ≥18 years who had T2DM, were either Black or White, had no previous hHF, and were prescribed empagliflozin between August 2014 and December 2019. Our primary outcome was time to first hHF after the initial prescription of empagliflozin. A propensity-score (PS)-weighted analysis was performed to balance characteristics by race. The inverse probability treatment weighting method based on PS was used to make treatment comparisons. To compare Black with White, a PS-weighted Cox's cause-specific hazards model was used. RESULTS: In total, 8789 participants were eligible for inclusion (Black = 3216 vs. White = 5573). The Black cohort was significantly younger, had a higher proportion of females, and had a higher prevalence of chronic kidney disease, hypertension and diabetic retinopathy, while the White cohort had a higher prevalence of coronary artery disease. After adjustment for confounding factors such as age, gender, coronary artery disease, hypertension and diabetic retinopathy, the hazard ratio for first-time hHF was not significantly different between the two racial groups [hazard ratio (95% confidence interval) = 1.09 (0.84-1.42), p = .52]. CONCLUSION: This study showed no significant difference in incident hHF among Black versus White individuals with T2DM following a prescription for empagliflozin.
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Compostos Benzidrílicos , Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Glucosídeos , Insuficiência Cardíaca , Hipertensão , Adulto , Feminino , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Hospitalização , Estudos Retrospectivos , Fatores de Risco , População Branca , Negro ou Afro-Americano , MasculinoRESUMO
INTRODUCTION: Three Yersinia species were identified from samples of drinking water from diverse geographic regions of Ireland. Conventional commercial biochemical identification systems classified them as Yersinia enterocolitica. Since this organism is the most common cause of bacterial gastroenteritis in some countries, further investigation was warranted. The aim of the study was to provide a microbial characterisation of three Yersinia species, to determine their pathogenicity, and to review the incidence rate of Yersinia enterocolitica detection in our region. METHODS: Organism identification was performed using conventional commercial diagnostic systems MALDI-TOF, API 20E, API 50CHE, TREK Sensititre GNID and Vitek 2 GN, and whole genome sequencing (WGS) was performed. Historical data for detections was extracted from the lab system for 2008 to 2023. RESULTS: All three isolates gave "good" identifications of Yersinia enterocolitica on conventional systems. Further analysis by WGS matched two of the isolates with recently described Yersinia proxima, and the third was a member of the non-pathogenic Yersinia enterocolitica clade 1Aa. DISCUSSION: Our analysis of these three isolates deemed them to be Yersinia species not known currently to be pathogenic, but determining this necessitated the use of next-generation sequencing and advanced bioinformatics. Our work highlights the importance of having this technology available to public laboratories, either locally or in a national reference laboratory. The introduction of molecular technologies for the detection of Yersinia species may increase the rate of detections. Accurate identification of significant pathogens in environmental, public health and clinical microbiology laboratories is critically important for the protection of society.
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Água Potável , Yersinia enterocolitica , Yersinia enterocolitica/isolamento & purificação , Yersinia enterocolitica/genética , Irlanda/epidemiologia , Água Potável/microbiologia , Humanos , Yersiniose/epidemiologia , Yersiniose/microbiologia , Sequenciamento Completo do Genoma , Microbiologia da ÁguaRESUMO
Biocrusts dominate the soil surface in deserts and are composed of diverse microbial communities that provide important ecosystem services. Cyanobacteria in biocrusts produce many secondary metabolites, including the neurotoxins BMAA, AEG, DAB, anatoxin-a(S) (guanitoxin), and the microcystin hepatotoxins, all known or suspected to cause disease or illness in humans and other animals. We examined cyanobacterial growth and prevalence of these toxins in biocrusts at millimeter-scales, under a desert-relevant illumination gradient. In contrast to previous work, we showed that hydration had an overall positive effect on growth and toxin accumulation, that nitrogen was not correlated with growth or toxin production, and that phosphorus enrichment negatively affected AEG and BMAA concentrations. Excess illumination positively correlated with AEG, and negatively correlated with all other toxins and growth. Basic pH negatively affected only the accumulation of BMAA. Anatoxin-a(S) (guanitoxin) was not correlated with any tested variables, while microcystins were not detected in any of the samples. Concerning toxin pools, AEG and BMAA were good predictors of the presence of one another. In a newly conceptualized scheme, we integrate aspects of biocrust growth and toxin pool accumulations with arid-relevant desertification drivers.
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INTRODUCTION: Greater than half of in-hospital maternal deaths are caused by sepsis, a condition that occurs when infection exceeds local tissue containment and results in organ dysfunction. Determining the source of infection can be challenging. Microbiological cultures of the uterine cavity are often difficult to obtain, so antimicrobial susceptibility results may not be available to guide treatment. The aim of this retrospective study was to assess the potential clinical value of microbiology samples used in the maternal "septic screen" of patients in an Irish maternity hospital. METHODS: A review was completed of all maternal "septic screen" (i.e., high vaginal swabs, placenta swabs, blood cultures, throat swabs and urine samples) microbiology results from July 2016 to December 2021. RESULTS: In the relevant period, 845 patients were subject to a "septic screen", of whom 430 also had a placental swab collected. These 430 patients comprise our study population. 2% of blood cultures yielded potential pathogens, compared with 37%, 33%, 9% and 7% respectively for placental swabs, high vaginal swabs, throat swabs and urine specimens. 95% of blood cultures were sterile, compared with 52%, 0%, 0% and 53% respectively for placental swabs, high vaginal swabs, throat swabs and urine specimens. CONCLUSION: Of the five microbiological specimen types examined, placental swabs yielded the highest number of potential pathogens. Our results suggest that placental swabs are useful specimens for detecting potential pathogens from the uterine cavity, the most common source of perinatal infections.