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Background Frailty is prevalent in older adults with heart failure and is associated with poor outcomes; however, there remains uncertainty on how to measure frailty in clinical practice. Methods and Results A multicentric prospective cohort study was assembled at 4 heart failure clinics to compare the prognostic value of 3 physical frailty scales in ambulatory patients with heart failure. Outcomes were all-cause death or hospitalization and health-related quality of life using the 36-Item Short Form survey questionnaire (SF-36) at 3 months. Multivariable regression was adjusted for age, sex, Meta-Analysis Global Group in Chronic Heart Failure score, and baseline SF-36 score. The cohort included 215 patients (mean age 77.6 years). All 3 frailty scales were independently associated with death or hospitalization at 3 months; the adjusted odds ratios standardized per 1 SD worsening of the Short Physical Performance Battery; Fried, and strength, assistance with walking, rising from a chair, climbing stairs, and falls scales were 1.67 (95% CI, 1.09-2.55), 1.60 (95% CI, 1.04-2.46), and 1.55 (95% CI, 1.03-2.35), respectively, with C statistics of 0.77 to 0.78. All 3 frailty scales were independently associated with worsening SF-36 scores, especially the Short Physical Performance Battery, for which 1 SD worsening of frailty translated to a decrement of -5.86 (-8.55 to -3.17) and -5.51 (-7.82 to -3.21) points in the Physical Component Score and Mental Component Score. Conclusions All 3 physical frailty scales were associated with death, hospitalization, and reduced health-related quality of life in ambulatory patients with heart failure. Questionnaire or performance-based physical frailty scales can be used to offer prognostic value and a therapeutic target in this vulnerable population. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03887351.
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Fragilidade , Insuficiência Cardíaca , Humanos , Idoso , Fragilidade/diagnóstico , Fragilidade/complicações , Qualidade de Vida , Estudos Prospectivos , Insuficiência Cardíaca/tratamento farmacológico , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Global circumferential strain (GCS) and global radial strain (GRS) are reduced with cytotoxic chemotherapy. There are limited data on the effect of immune checkpoint inhibitor (ICI) myocarditis on GCS and GRS. OBJECTIVES: This study aimed to detail the role of GCS and GRS in ICI myocarditis. METHODS: In this retrospective study, GCS and GRS from 75 cases of patients with ICI myocarditis and 50 ICI-treated patients without myocarditis (controls) were compared. Pre-ICI GCS and GRS were available for 12 cases and 50 controls. Measurements were performed in a core laboratory blinded to group and time. Major adverse cardiovascular events (MACEs) were defined as a composite of cardiogenic shock, cardiac arrest, complete heart block, and cardiac death. RESULTS: Cases and controls were similar in age (66 ± 15 years vs 63 ± 12 years; P = 0.20), sex (male: 73% vs 61%; P = 0.20) and cancer type (P = 0.08). Pre-ICI GCS and GRS were also similar (GCS: 22.6% ± 3.4% vs 23.5% ± 3.8%; P = 0.14; GRS: 45.5% ± 6.2% vs 43.6% ± 8.8%; P = 0.24). Overall, 56% (n = 42) of patients with myocarditis presented with preserved left ventricular ejection fraction (LVEF). GCS and GRS were lower in myocarditis compared with on-ICI controls (GCS: 17.5% ± 4.2% vs 23.6% ± 3.0%; P < 0.001; GRS: 28.6% ± 6.7% vs 47.0% ± 7.4%; P < 0.001). Over a median follow-up of 30 days, 28 cardiovascular events occurred. A GCS (HR: 4.9 [95% CI: 1.6-15.0]; P = 0.005) and GRS (HR: 3.9 [95% CI: 1.4-10.8]; P = 0.008) below the median was associated with an increased event rate. In receiver-operating characteristic (ROC) curves, GCS (AUC: 0.80 [95% CI: 0.70-0.91]) and GRS (AUC: 0.76 [95% CI: 0.64-0.88]) showed better performance than cardiac troponin T (cTnT) (AUC: 0.70 [95% CI: 0.58-0.82]), LVEF (AUC: 0.69 [95% CI: 0.56-0.81]), and age (AUC: 0.54 [95% CI: 0.40-0.68]). Net reclassification index and integrated discrimination improvement demonstrated incremental prognostic utility of GRS over LVEF (P = 0.04) and GCS over cTnT (P = 0.002). CONCLUSIONS: GCS and GRS are lower in ICI myocarditis, and the magnitude of reduction has prognostic significance.
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Miocardite , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Miocardite/induzido quimicamente , Miocardite/diagnóstico por imagem , Miocardite/complicações , Volume Sistólico , Função Ventricular Esquerda , Inibidores de Checkpoint Imunológico , Estudos Retrospectivos , Valor Preditivo dos Testes , Troponina TAssuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Fatores Imunológicos , ImunoterapiaRESUMO
Agricultural reuse of treated wastewater (TWW) for irrigation is widely practiced. Its conjunctive use with freshwater is becoming more common to guarantee food security, while the rationale behind and its sustainability are quite arguable. The objective of this study is to better understand the drivers of the conjunctive use of TWW and groundwater (GW) in Nabeul region, Tunisia, and the potential environmental and health impacts taking into account farmers' practices and attitudes toward reuse. TWW used for irrigation exhibited relatively high salinity and high microbiological load. GW has a very high salinity. TWW and GW showed low concentrations of heavy metals (Al, Cd, Co, Cu, Cr, Mn, Ni, Pb, and Zn). Concentrations of pharmaceutical compounds were between Limits of Quantification and 13 µg/L. In GW, values were relatively high, especially for caffeine, carbamazepine, ofloxacin, and ketoprofen. Farmers have a low perception of the polluting load of TWW and GW and of their potential long-term impacts on agricultural environment, human health, and agricultural productivity. GW availability has facilitated its conjunctive use with TWW, either to augment water quantity and/or to improve its quality. Despite its low quality, GW timeliness for irrigation was the main driver to guarantee a better yield and quality of produces. Soil microbial community, bacterial biomass, denitrifying potential and carbon oxidation profiles were similar under TWW, GW and their conjunctive use. Though an effect of the sampling period was observed with a high abundance of denitrifying bacteria in the wet season and a low carbon oxidation activity at the end of the dry season. The conjunctive use of TWW and GW is very likely unsustainable from health and environmental perspectives. Balancing farmers' economic profit against the preservation of agricultural activity, linked to cultural and natural heritage, remains one of the challenges for decision-makers and regional stakeholders.
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Irrigação Agrícola , Água Subterrânea , Atitude , Fazendeiros , Humanos , Águas Residuárias/análise , ÁguaRESUMO
We describe the case of a 54-year-old woman admitted to the cardiology ward for the correction of radiation-induced aortic stenosis and coronary artery disease. After careful workup, she underwent surgical aortic valve replacement and aortocoronary bypass with venous grafts. This case demonstrates the late cardiovascular complications that can develop after radiation therapy for cancer, and the surgical complexity of these patients. Thorough workup is needed for the treatment of radiation-induced valvulopathy and coronary artery disease, as these patients are often poor surgical candidates with hostile chests. Multidisciplinary heart-team assessment is paramount, and consideration should be given to catheter-based approaches.
Nous décrivons le cas d'une femme de 54 ans admise en cardiologie pour la correction d'une sténose aortique radio-induite et une coronaropathie. Après un bilan minutieux, elle a subi un remplacement valvulaire aortique chirurgical et un pontage aortocoronarien à l'aide de greffons veineux. Ce cas démontre les complications cardiovasculaires tardives qui peuvent survenir après la radiothérapie administrée pour un cancer, et la complexité de l'intervention chirurgicale de ces patients. Un bilan complet est nécessaire avant le traitement de la valvulopathie radio-induite et de la coronaropathie, puisque ces patients sont souvent de mauvais candidats à l'intervention chirurgicale en raison de thorax « hostiles ¼. Il est primordial que l'équipe multidisciplinaire en cardiologie réalise l'évaluation et il faudrait envisager les approches par cathéter.
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Establishing consistent relationships between neural activity and behavior is a challenge in human cognitive neuroscience research. We addressed this issue using variable time constraints in an oddball frequency-sweep design for visual discrimination of complex images (face exemplars). Sixteen participants viewed sequences of ascending presentation durations, from 25 to 333 ms (40-3 Hz stimulation rate) while their electroencephalogram (EEG) was recorded. Throughout each sequence, the same unfamiliar face picture was repeated with variable size and luminance changes while different unfamiliar facial identities appeared every 1 s (1 Hz). A neural face individuation response, tagged at 1 Hz and its unique harmonics, emerged over the occipito-temporal cortex at 50 ms stimulus duration (25-100 ms across individuals), with an optimal response reached at 170 ms stimulus duration. In a subsequent experiment, identity changes appeared non-periodically within fixed-frequency sequences while the same participants performed an explicit face individuation task. The behavioral face individuation response also emerged at 50 ms presentation time, and behavioral accuracy correlated with individual participants' neural response amplitude in a weighted middle stimulus duration range (50-125 ms). Moreover, the latency of the neural response peaking between 180 and 200 ms correlated strongly with individuals' behavioral accuracy in this middle duration range, as measured independently. These observations point to the minimal (50 ms) and optimal (170 ms) stimulus durations for human face individuation and provide novel evidence that inter-individual differences in the magnitude and latency of early, high-level neural responses are predictive of behavioral differences in performance at this function.
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Reconhecimento Facial , Discriminação Psicológica , Eletroencefalografia , Face , Humanos , Reconhecimento Visual de Modelos , Estimulação LuminosaRESUMO
Metal(loid) soil pollution resulting from mining activities is an important issue that has negative effects on the environment (soil acidification, lack of vegetation, groundwater pollution) and human health (cancer, chronic diseases). In the context of a phytostabilization process for the bioremediation of a mine soil highly contaminated by arsenic (As) and lead (Pb), a pot experiment was set up to study the effect of plant sowing and microbial inoculation on soil properties, metal(loid) (im)mobilization in soil and accumulation in plant, and plant growth. For this, mine soil was sown with endemic metallicolous Agrostis seeds and/or inoculated with endogenous microbial consortia previously selected for their As and Pb tolerance. Agrostis was able to develop on the contaminated mine soil and immobilized metal(loid)s through metal(loid) accumulation in the roots. Its growth was improved by microbial consortium inoculation. Moreover, microbial consortium inoculation increased soil organic content and electrical conductivity, and led to an increase in soil microbial activities (linked to C and P cycles); however, it also induced a metal(loid) mobilization. In conclusion, microbial consortium inoculation stimulated the growth of endemic Agrostis plants and thus ameliorated the phytostabilization of a former mine soil highly polluted by As and Pb. This study is thus a good example of the benefits of coupling several approaches such as phytostabilization and bioaugmentation for the bioremediation of former mine contaminated sites.
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Agrostis , Poluentes do Solo , Biodegradação Ambiental , Humanos , Consórcios Microbianos , Solo , Poluentes do Solo/análiseRESUMO
The impact of two pesticides (S-metolachlor and propiconazole) and their respective main metabolites (ESA-metolachlor and 1,2,4-triazole) on bacterial denitrification in groundwater was studied. For this, the denitrification activity and the bacterial diversity of a microbial community sampled from a nitrate-contaminated groundwater were monitored during 20 days in lab experiments in the presence or absence of pesticides or metabolites at 2 or 10 µg/L. The kinetics of nitrate reduction along with nitrite and N2O production all suggested that S-metolachlor had no or only little impact, whereas its metabolite ESA-metolachlor inhibited denitrification by 65% at 10 µg/L. Propiconazole and 1,2,4-triazole also inhibited denitrification at both concentrations, but to a lesser extent (29-38%) than ESA-metolachlor. When inhibition occurred, pesticides affected the reduction of nitrate into nitrite step. However, no significant differences were detected on the abundance of nitrate reductase narG and napA genes, suggesting an impact of pesticides/metabolites at the protein level rather than on denitrifying bacteria abundance. 16S rRNA gene Illumina sequencing indicated no major modification of bacterial diversity in the presence or absence of pesticides/metabolites, except for ESA-metolachlor and propiconazole at 10 µg/L that tended to increase or decrease Shannon and InvSimpson indices, respectively. General growth parameters suggested no impact of pesticides, except for propiconazole at 10 µg/L that partially inhibited acetate uptake and induced a decrease in microbial biomass. In conclusion, pesticides and metabolites can have side effects at environmental concentrations on microbial denitrification in groundwater and may thus affect ecosystem services based on microbial activities.
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Nitrate contamination of groundwater remains a major concern despite all the measures and efforts undertaken over the last decades to protect water resources. We focused on a small catchment in Brittany (France) facing nitrate pollution with concentrations over the European drinking water standard of 50 mg.L-1. This is a common situation in catchments where - supposedly effective - measures were applied for reducing the transfer of N to groundwater. At the scale of this small (~100 ha) basement aquifer, nitrate concentrations are very heterogeneous in the groundwater, sampled up to 15-20 m below the soil surface in several observation wells (hereafter referred as piezometers) and up to 110 m deep in a borehole drilled through a faulted area near the Spring (outlet of the catchment). We used complementary and robust approaches for exploring and constraining the driving parameters of nitrate transfer and distribution in groundwater. Detailed geological work and a geophysical electrical resistivity tomography survey identified the lithologies, tectonic structures and weathering layers. This highlighted a complex geological structure with several compartments delimited by faults, as well as the highly variable thickness of the weathered layer. It also illustrated the heterogeneity of the hydrosystem, some compartments appearing to be disconnected from the general groundwater flow. This was confirmed by geochemical analyses and by the mean apparent groundwater residence time based on CFCs-SF6 and noble-gas analyses, locally revealing old and nitrate-free groundwater, and very old water with a recharge temperature below than the current average temperature in the area, reflecting water dating back to the last period of glaciation (-19 to -17 ky). Nitrate isotopes clearly showed denitrification processes in a few piezometers, which was generally supported by microbiology and molecular biology results. This highlighted the presence of functional genes involved in denitrification as well as a capacity of the groundwater microbial community to denitrify when in situ conditions are favourable. This type of combined approach - covering chemistry, isotopic methods, dissolved gases, microbiological activity, geophysics and hydrogeology - appears to be indispensable for implementing the most relevant programme of measures and for accurately assessing their effectiveness, notably by considering the timeframe between implementation of the measures and their impact on groundwater quality.
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Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Isótopos , Nitratos/análise , Poluentes Químicos da Água/análiseRESUMO
The development of biofilms on modified natural zeolites was investigated with purpose to obtain biocomposites with biodegradation activity towards pesticides MCPA (2-methyl-4-chlorophenoxyacetic acid) and glyphosate (N-(phosphonomethyl)glycine) for potential application in bioaugmentation of polluted agricultural soils. Microbial communities were selected from agricultural pesticide-contaminated soil/water samples and enriched on the basis of their ability to biodegrade the pesticides. In order to enhance affinity of microbial communities to the support material, the natural mineral zeolite was modified by nontoxic environmentally friendly cations (Li+, Na+, K+, NH4+, H+, Mg2+, Ca2+, Fe3+) by methods preserving its structure and characterised using powder XRD, surface area measurement and chemical composition analysis. Kinetics of pesticide degradation by the biocomposites was studied in liquid media. Results showed that according to zeolite modifications, the microbial activity and biodiversity changed. The best biodegradation rate of MCPA and glyphosate reached 0.12-0.13 mg/h with half-life of 16-18 h, which is considerably quicker than observed in natural environment. However, in some cases, biodegradation activity towards pesticides was lost which was connected to unfavourable zeolite modification and accumulation of toxic metabolites. High-throughput sequencing on the 16S rRNA genes of the biofilm communities highlighted the selection of bacteria genera known to metabolise MCPA (Aminobacter, Cupriavidus, Novosphingobium, Pseudomonas, Rhodococcus, Sphingobium and Sphingopyxis) and glyphosate (Pseudomonas). Altogether, results suggested that zeolites do not only have a passive role of biofilm support but also have protective and nutrient-supportive functions that consequently increase biodiversity of the pesticide degraders growing in the biofilm and influence the pesticide biodegradation rate.
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Cupriavidus , Praguicidas , Poluentes do Solo , Zeolitas , Biodegradação Ambiental , Biofilmes , RNA Ribossômico 16S , Microbiologia do SoloRESUMO
BACKGROUND: Myocarditis is a potentially fatal complication of immune checkpoint inhibitor (ICI) therapy. Data on the utility of cardiovascular magnetic resonance (CMR) T1 and T2 mapping in ICI myocarditis are limited. OBJECTIVES: This study sought to assess the value of CMR T1 and T2 mapping in patients with ICI myocarditis. METHODS: In this retrospective study from an international registry of patients with ICI myocarditis, clinical and CMR findings (including T1 and T2 maps) were collected. Abnormal T1 and T2 were defined as 2 SD above site (vendor/field strength specific) reference values and a z-score was calculated for each patient. Major adverse cardiovascular events (MACE) were a composite of cardiovascular death, cardiogenic shock, cardiac arrest, and complete heart block. RESULTS: Of 136 patients with ICI myocarditis with a CMR, 86 (63%) had T1 maps and 79 (58%) also had T2 maps. Among the 86 patients (66.3 ± 13.1 years of age), 36 (41.9%) had a left ventricular ejection fraction <55%. Across all patients, mean z-scores for T1 and T2 values were 2.9 ± 1.9 (p < 0.001) and 2.2 ± 2.1 (p < 0.001), respectively. On Siemens 1.5-T scanner (n = 67), native T1 (1,079.0 ± 55.5 ms vs. 1,000.3 ± 22.1 ms; p < 0.001) and T2 (56.2 ± 4.9 ms vs. 49.8 ± 2.2 ms; p < 0.001) values were elevated compared with reference values. Abnormal T1 and T2 values were seen in 78% and 43% of the patients, respectively. Applying the modified Lake Louise Criteria, 95% met the nonischemic myocardial injury criteria and 53% met the myocardial edema criteria. Native T1 values had excellent discriminatory value for subsequent MACE, with an area under the curve of 0.91 (95% confidence interval: 0.84 to 0.98). Native T1 values (for every 1-unit increase in z-score, hazard ratio: 1.44; 95% confidence interval: 1.12 to 1.84; p = 0.004) but not T2 values were independently associated with subsequent MACE. CONCLUSIONS: The use of T1 mapping and application of the modified Lake Louise Criteria provides important diagnostic value, and T1 mapping provides prognostic value in patients with ICI myocarditis.
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Inibidores de Checkpoint Imunológico/efeitos adversos , Imageamento por Ressonância Magnética , Miocardite/induzido quimicamente , Miocardite/diagnóstico por imagem , Idoso , Técnicas de Imagem Cardíaca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/patologia , Estudos RetrospectivosRESUMO
Mitral valve prolapse is a common finding in Graves' disease. However, severe mitral regurgitation (MR) is a relatively uncommon manifestation of Graves' disease. We report a case of a 32-year-old woman with toxic Graves' disease and MR. The echocardiogram was suggestive of severe MR with biventricular failure, severe enough to be considered for mitral valve replacement. With medical control of the thyrotoxic state, a repeat echocardiogram revealed only trace MR, with normal left ventricular function. The timely management of the thyrotoxic state in this patient with Graves' disease and moderate to severe MR possibly related to myxomatous degeneration, averted the need for mitral valve replacement.
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Antagonistas Adrenérgicos beta/uso terapêutico , Antitireóideos/uso terapêutico , Doença de Graves/fisiopatologia , Hipertireoidismo , Metimazol/uso terapêutico , Propranolol/uso terapêutico , Adulto , Ecocardiografia , Fadiga/etiologia , Feminino , Humanos , Hipertireoidismo/diagnóstico , Hipertireoidismo/tratamento farmacológico , Insuficiência da Valva MitralRESUMO
A turbidimetric test for rapid quantification of As(III) (detection limit of 3 mg/L, quantification range of 10-100 mg/L) in liquid growth medium was developed for assessing and monitoring microbial As(III)-oxidizing and As(V)-reducing activities. This test is based on As(III) chelation with pyrrolidine dithiocarbamate followed by spectrometric measurement of absorbance, and was validated by comparison with AAS quantification of As after As(III)/As(V) separation.
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Arsênio/análise , Arsênio/química , Bactérias/metabolismo , Técnicas Microbiológicas/métodos , Biotransformação , Burkholderiales , Calibragem , Microbiota/fisiologia , Pirrolidinas , Sensibilidade e Especificidade , TiocarbamatosRESUMO
We report normative data from a large (N = 307) sample of young adult participants tested with a computerized version of the long form of the classical Benton Facial Recognition Test (BFRT; Benton & Van Allen, 1968). The BFRT-c requires participants to match a target face photograph to either one or three of six face photographs presented simultaneously. We found that the percent accuracy on the BFRT-c (81%-83%) was below ceiling yet well above chance level, with little interindividual variance in this typical population sample, two important aspects of a sensitive clinical test. Although the split-half reliability on response accuracy was relatively low, due to the large variability in difficulty across items, the correct response times measured in this version-completed in 3 min, on average-provide a reliable and critical complementary measure of performance at individual unfamiliar-face matching. In line with previous observations from other measures, females outperformed male participants at the BFRT-c, especially for female faces. In general, performance was also lower following lighting changes than following head rotations, in line with previous studies that have emphasized participants' limited ability to match pictures of unfamiliar faces with important variations in illumination. Overall, this normative data set supports the validity of the BFRT-c as a key component of a battery of tests to identify clinical impairments in individual face recognition, such as observed in acquired prosopagnosia. However, this analysis strongly recommends that researchers consider the full test results: Beyond global indexes of performance based on accuracy rates only, they should consider the time taken to match individual faces as well as the variability in performance across items.
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Reconhecimento Facial , Iluminação , Tempo de Reação , Reconhecimento Psicológico , Adolescente , Desenho Assistido por Computador , Confiabilidade dos Dados , Feminino , Humanos , Iluminação/métodos , Iluminação/normas , Masculino , Testes Neuropsicológicos/normas , Prosopagnosia/diagnóstico , Reprodutibilidade dos Testes , Adulto JovemRESUMO
Nanoparticles (NP) used as remediation agents for groundwater treatment may interact with biofilms naturally present, altering NP mobility and/or reactivity and thereby NP effectiveness. The influence of the presence of a multi species biofilm on the mobility of two types of zero-valent iron NP (nZVI; NANOFER 25S and optimized NANOFER STAR, NanoIron s.r.o. (Czech Republic)) was tested in laboratory experiments with columns mimicking aquifer conditions. Biofilms were grown in columns filled with sand in nitrate reducing conditions using groundwater from an industrial site as inoculum. After two months growth, they were composed of several bacterial species, dominated by Pseudomonas stutzeri. Biofilm strongly affected the physical characteristics of the sand, decreasing total porosity from ~30% to ~15%, and creating preferential pathways with high flow velocities. nZVI suspensions were injected into the columns at a seepage velocity of 10mday-1. Presence of biofilm did not impact the concentrations of Fe at the column outlet nor the amount of total Fe retained in the sand, as attested by the measurement of magnetic susceptibility. However, it had a significant impact on NP size sorting as well as on total Fe distribution along the column. This suggests nZVI-biofilm interactions that were confirmed by microscopic observations using SEM/STEM coupled with energy-dispersive X-ray spectroscopy. Our study shows that biofilm modifies the water flow velocity in the porous media, favoring the transport of large aggregates and decreased NP mobility due to physical and chemical interactions.
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Biofilmes , Água Subterrânea/química , Ferro/química , Nanopartículas Metálicas/química , Porosidade , Pseudomonas stutzeriRESUMO
Understanding biofilm interactions with surrounding substratum and pollutants/particles can benefit from the application of existing microscopy tools. Using the example of biofilm interactions with zero-valent iron nanoparticles (nZVI), this study aims to apply various approaches in biofilm preparation and labeling for fluorescent or electron microscopy and energy dispersive X-ray spectrometry (EDS) microanalysis for accurate observations. According to the targeted microscopy method, biofilms were sampled as flocs or attached biofilm, submitted to labeling using 4',6-diamidino-2-phenylindol, lectins PNA and ConA coupled to fluorescent dye or gold nanoparticles, and prepared for observation (fixation, cross-section, freezing, ultramicrotomy). Fluorescent microscopy revealed that nZVI were embedded in the biofilm structure as aggregates but the resolution was insufficient to observe individual nZVI. Cryo-scanning electron microscopy (SEM) observations showed nZVI aggregates close to bacteria, but it was not possible to confirm direct interactions between nZVI and cell membranes. Scanning transmission electron microscopy in the SEM (STEM-in-SEM) showed that nZVI aggregates could enter the biofilm to a depth of 7-11 µm. Bacteria were surrounded by a ring of extracellular polymeric substances (EPS) preventing direct nZVI/membrane interactions. STEM/EDS mapping revealed a co-localization of nZVI aggregates with lectins suggesting a potential role of EPS in nZVI embedding. Thus, the combination of divergent microscopy approaches is a good approach to better understand and characterize biofilm/metal interactions.
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In situ biofilm sampling is a key step for the study of natural biofilms and using methodologies that reflect natural diversity is necessary to guarantee representative sampling. Here, we focalise on the impact of the type of substrata on which biofilms grow on bacterial and fungal communities' structure. The indirect molecular approach, Denaturing Gel Gradient Electrophoresis (DGGE) of a gene fragment coding for either 16S rRNA or 28S rRNA, for bacteria or fungi respectively, was used to evaluate the variability of microbial community structures among different biofilm substrata: natural (pebbles, live plants, wood and sediment), or artificial (glass, Plexiglas(®) and sterile wood), in a small river (the Loiret, France). Multivariate statistics, band richness and diversity indexes (Shannon and Simpson) were used to highlight variations in community structure between substrata. Results showed variations of bacterial and fungal diversity between different substrata according to substratum properties/origin (natural or artificial, organic or inorganic) but there was no optimal substratum for sampling, and artificial substrata were not significantly less applicable than natural substrata. Pooling 4 different substrata types allowed a higher bacterial and fungal biodiversity recovery. Point contact sampling may thus gain in robustness by increasing the number of substrata considered. Fungal species richness was similar to the bacterial one on most substrata which suggested they should be more frequently considered in riverine biofilm studies.
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The aim of the present study was to investigate interactions of the antibiotic ciprofloxacin (CIP), titanium dioxide nanoparticles (TiO2 NP) and natural organic matter (NOM) in aqueous suspensions. The mean hydrodynamic diameter of particles of TiO2 NP and NOM in the suspensions ranged from 113 to 255nm. During batch experiments the radioactivity resulting from (14)CIP was determined in the filtrate (filter pore size 100nm) by scintillation measurements. Up to 72h, no significant sorption of NOM to TiO2 NP was observed at a TiO2 NP concentration of 5mg/L. When the concentration of TiO2 NP was increased to 500mg/L, a small amount of NOM of 9.5%±0.6% was sorbed at 72h. The low sorption affinity of NOM on TiO2 NP surfaces could be explained by the negative charge of both components in alkaline media or by the low hydrophobicity of the NOM contents. At a TiO2 NP concentration of 5mgL(-1), the sorption of CIP on TiO2 NP was insignificant (TiO2 NP/CIP ratio: 10). When the TiO2 NP/CIP ratio was increased to 1000, a significant amount of 53.6%±7.2% of CIP was sorbed on TiO2 NP under equilibrium conditions at 64h. In alkaline media, CIP is present mainly as zwitterions which have an affinity to sorb on negatively charged TiO2 NP surfaces. The sorption of CIP on TiO2 NP in the range of TiO2 NP concentrations currently estimated for municipal wastewater treatment plants is estimated to be rather low. The Freundlich sorption coefficients (KF) in the presence of NOM of 2167L(n)mgmg(-n)kg(-1) was about 10 times lower than in the absence of NOM. This is an indication that the particle fraction of NOM<100nm could play a role as a carrier for ionic organic micro-pollutants as CIP.
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Antibacterianos/química , Ciprofloxacina/química , Substâncias Húmicas , Nanopartículas Metálicas/química , Titânio/química , Poluentes Químicos da Água/química , Adsorção , Monitoramento Ambiental , SuspensõesRESUMO
BACKGROUND: Several echocardiographic measures have prognostic value in heart failure (HF). However, no definitive data exist on how changes in these parameters with treatment affect survival in this patient population. We hypothesized that early improvement on echocardiography could predict long-term survival. METHODS AND RESULTS: We conducted a retrospective review of 404 patients seen in the HF clinic from 2002 to 2008 (6.5 years). Patients had one echocardiogram ≤1 year before and another ≥1 month (10 ± 7 months) after treatment onset. We studied changes in standard echocardiographic parameters, including left (LV) and right (RV) ventricular size and/or function (systolic and/or diastolic), valvular (mitral and tricuspid) function, and pulmonary artery pressure. Survival curves and hazard ratios were generated for patients showing improvement on the 2nd echocardiogram versus those who did not. Multivariable analyses were performed adjusting for age, sex, ischemic etiology, and significant baseline echocardiographic parameters. Average follow-up was 2.9 ± 1.5 years. Improvement in LV end-systolic dimension, RV function, and mitral regurgitation were independent predictors of 5-year survival (P < .05) and, importantly, more predictive than baseline values of these parameters alone (higher hazard ratios). CONCLUSIONS: Early echocardiographic improvement is strongly associated with 5-year survival in patients with HF. Serial echocardiography may aid in stratifying patient care.
Assuntos
Insuficiência Cardíaca , Ventrículos do Coração , Insuficiência da Valva Mitral , Idoso , Idoso de 80 Anos ou mais , Gerenciamento Clínico , Ecocardiografia/métodos , Ecocardiografia/estatística & dados numéricos , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/etiologia , Monitorização Fisiológica/métodos , Tamanho do Órgão , Valor Preditivo dos Testes , Prognóstico , Quebeque/epidemiologia , Estudos Retrospectivos , Análise de SobrevidaRESUMO
Three commercial granular activated carbons (GACs) were studied at laboratory scale with a view to the combined adsorption and biodegradation of PCBs in aquatic sediment. The three GACs, with contrasting physico-chemical characteristics, all show a high adsorption of PCBs and are thus capable of reducing aqueous pollutant concentrations. After a one-month incubation with 'Aroclor 1242'-spiked sediment, the three GACs were each colonized by a multispecies biofilm, although with different amounts of attached bacterial biomass and significantly distinct genetic bacterial communities; interestingly, the highest bacterial biomass was attached to the microporous vegetable GAC. The multispecies biofilms developed on the three GACs were all predominantly composed of Proteobacteria, especially the ß-, γ- and δ- subclasses, Chloroflexi and Acidobacteria, with genera previously found in environments containing PCBs or biphenyls, or able to perform cometabolic and direct PCB degradation. After an eight-month incubation under aerobic conditions, it was only the vegetable Picabiol GAC, with its low microporous volume, high total surface area and acidic property, that showed a significant (21%) reduction of tri- through penta-CB. Our results suggest that PCB bio-transformation by the bacterial community attached to the GAC is influenced by GAC's physico-chemical characteristics. Thus, a properly selected GAC could effectively be used to a) sequestrate and concentrate PCB from contaminated aquatic sediment and b) act as a support for efficient PCB degradation by an autochthonous bacterial biofilm.