ABSTRACT
A method for the enzymatic determination of atropine has been developed, which is based on a sequence of reactions involving (1) the hydrolysis of atropine to give tropine; (2) the enzymatic oxidation of tropine with NAD (catalysed by tropinone reductase); and (3) an indicator reaction, in which the NADH previously formed reduces the dye iodonitrotetrazolium chloride (INT) to a reddish species, the reaction catalysed by diaphorase. The method was first developed in solution (linear response range from 2.4 × 10-6 M to 1.0 × 10-4 M). It was then implemented in cellulose platforms to develop a rapid test where the determination is made by measuring the RGB coordinates of the platforms using a smartphone-based device. The device is based on the integrating sphere concept and contains a light source to avoid external illumination effects. The smartphone is controlled by an app that allows a calibration line to be generated and the atropine concentration to be quantified; moreover, since the app normalizes the CCD response of the smartphone, the results and calibrations obtained with different smartphones are similar and can be shared. Using the G coordinate, the results were shown to have a linear response with the concentration of atropine ranging from 1.2 × 10-5 M to 3.0 × 10-4 M with an RSD of 1.4% (n = 5). The method has been applied to the determination of atropine in baby food and buckwheat samples with good results.
ABSTRACT
Anterior knee pain is a common condition that affects adolescent and young adult patients, being one of the most challenging consultations for a knee surgeon. The large number of distinct diagnoses makes it a peculiar syndrome, the only similarities being the presence of retro or peripatellar pain aggravated by at least one activity that loads the joint in flexion. From a pathophysiological perspective, an overuse injury should be considered, where the structural unit of the tissue is damaged or its capacity for reparative response is exceeded. The diagnosis is clinical. Images should be reserved for a particular group of patients. Early intervention is essential to achieve favorable results. Conservative treatment is the gold standard and it is based on multimodal management validated by international consensus. Based on a categorization by clinic and images, we can have a guide to those etiologies that are susceptible to surgical management. The goal of the intervention is to reduce joint stress. The present review defines a simplified algorithm for the study and management of anterior knee pain.
El dolor anterior de rodilla es una condición que afecta a pacientes adolescentes y adultos jóvenes, siendo una de las consultas más comunes y desafiantes para el cirujano de rodilla. La gran cantidad de diagnósticos diferenciales, lo convierten en un síndrome particular, que solo presentan en común la presencia de dolor retro o peripatelar agravado por al menos una actividad que cargue la articulación en flexión. Desde un punto de vista fisiopatológico, debe considerarse una lesión por sobrecarga, donde la unidad estructural del tejido se encuentra dañada o excedida su capacidad de respuesta reparadora. El diagnóstico es clínico. Las imágenes debiesen reservarse para un grupo particular de pacientes. La intervención precoz es fundamental para lograr resultados favorables. El tratamiento conservador es el estándar de oro y se basa en un manejo multimodal validado por consensos internacionales. Basados en una categorización por clínica e imágenes, podemos tener una guía de aquellos cuadros que son susceptibles de manejo quirúrgico. El objetivo de la intervención es reducir el estrés articular. La presente revisión define un algoritmo simplificado de estudio y manejo en dolor anterior de rodilla.
Subject(s)
Knee Joint , Pain , Adolescent , Young Adult , HumansABSTRACT
Resumen: El dolor anterior de rodilla es una condición que afecta a pacientes adolescentes y adultos jóvenes, siendo una de las consultas más comunes y desafiantes para el cirujano de rodilla. La gran cantidad de diagnósticos diferenciales, lo convierten en un síndrome particular, que solo presentan en común la presencia de dolor retro o peripatelar agravado por al menos una actividad que cargue la articulación en flexión. Desde un punto de vista fisiopatológico, debe considerarse una lesión por sobrecarga, donde la unidad estructural del tejido se encuentra dañada o excedida su capacidad de respuesta reparadora. El diagnóstico es clínico. Las imágenes debiesen reservarse para un grupo particular de pacientes. La intervención precoz es fundamental para lograr resultados favorables. El tratamiento conservador es el estándar de oro y se basa en un manejo multimodal validado por consensos internacionales. Basados en una categorización por clínica e imágenes, podemos tener una guía de aquellos cuadros que son susceptibles de manejo quirúrgico. El objetivo de la intervención es reducir el estrés articular. La presente revisión define un algoritmo simplificado de estudio y manejo en dolor anterior de rodilla.
Abstract: Anterior knee pain is a common condition that affects adolescent and young adult patients, being one of the most challenging consultations for a knee surgeon. The large number of distinct diagnoses makes it a peculiar syndrome, the only similarities being the presence of retro or peripatellar pain aggravated by at least one activity that loads the joint in flexion. From a pathophysiological perspective, an overuse injury should be considered, where the structural unit of the tissue is damaged or its capacity for reparative response is exceeded. The diagnosis is clinical. Images should be reserved for a particular group of patients. Early intervention is essential to achieve favorable results. Conservative treatment is the gold standard and it is based on multimodal management validated by international consensus. Based on a categorization by clinic and images, we can have a guide to those etiologies that are susceptible to surgical management. The goal of the intervention is to reduce joint stress. The present review defines a simplified algorithm for the study and management of anterior knee pain.
ABSTRACT
Objetivo Diversos estudios han identificado factores asociados con el riesgo de muerte en pacientes infectados por SARS-CoV-2. Sin embargo, su tamaño muestral ha sido muchas veces limitado, y sus resultados parcialmente contradictorios. Este estudio ha evaluado los factores asociados con la mortalidad por COVID-19 en la población madrileña mayor de 75 años, en los pacientes infectados y en los hospitalizados hasta enero de 2021. Pacientes y métodos Estudio de cohortes de base poblacional con todos los residentes de la Comunidad de Madrid nacidos antes del 1 de enero de 1945 y vivos a 31 de diciembre de 2019. Se obtuvieron variables demográficas y clínicas de la historia clínica electrónica de atención primaria (AP-Madrid), de los ingresos hospitalarios a través del Conjunto Mínimo Básico de Datos (CMBD) y de la mortalidad a través del Índice Nacional de Defunciones (INDEF). Se recogieron los datos de infección, hospitalización y muerte por SARS-CoV-2 entre el 1 de marzo e 2020 y el 31 de enero de 2021. Resultados De los 587.603 sujetos incluidos en la cohorte, 41.603 (7,1%) desarrollaron una infección confirmada por SARS-CoV-2. De ellos, 22.362 (53,7% de los infectados) se hospitalizaron y 11.251 (27%) murieron. El sexo masculino y la edad fueron los factores más asociados con la mortalidad, si bien también contribuyeron numerosas comorbilidades. La asociación fue de mayor magnitud en los análisis poblacionales que en los análisis con pacientes infectados u hospitalizados. La mortalidad en los hospitalizados fue menor en la segunda ola (33,4%) que en la primera ola (41,2%) de la pandemia Conclusión La edad, el sexo y las numerosas comorbilidades se asocian con el riesgo de muerte por COVID-19. La mortalidad en los pacientes hospitalizados se redujo apreciablemente después de la primera ola de la pandemia (AU)
Objective Various studies have identified factors associated with risk of mortality in patients with SARS-CoV-2 infection. However, their sample size has often been limited and their results partially contradictory. This study evaluated factors associated with COVID-19 mortality in the population of Madrid over 75 years of age, in infected patients, and in hospitalized patients up to January 2021. Patients and Methods This population-based cohort study analyzed all residents of the Community of Madrid born before January 1, 1945 who were alive as of December 31, 2019. Demographic and clinical data were obtained from primary care electronic medical records (PC-Madrid), data on hospital admissions from the Conjunto Mínimo Básico de Datos (CMBD, Minimum Data Set), and data on mortality from the Índice Nacional de Defunciones (INDEF, National Death Index). Data on SARS-CoV-2 infection, hospitalization, and death were collected from March 1, 2020 to January 31, 2021. Results A total of 587,603 subjects were included in the cohort. Of them, 41,603 (7.1%) had confirmed SARS-CoV-2 infection, of which 22,362 (53.7% of the infected individuals) were hospitalized and 11,251 (27%) died. Male sex and age were the factors most closely associated with mortality, though many comorbidities also had an influence. The associations were stronger in the analysis of the total population than in the analysis of infected or hospitalized patients. Mortality among hospitalized patients was lower during the second wave (33.4%) than during the first wave (41.2%) of the pandemic. Conclusion Age, sex, and numerous comorbidities are associated with risk of death due to COVID-19. Mortality in hospitalized patients declined notably after the first wave of the pandemic (AU)
Subject(s)
Humans , Male , Female , Aged , Aged, 80 and over , Coronavirus Infections/mortality , Pneumonia, Viral/mortality , Pandemics , Cohort Studies , Risk Factors , Age Factors , Spain/epidemiologyABSTRACT
OBJECTIVE: Various studies have identified factors associated with risk of mortality in patients with SARS-CoV-2 infection. However, their sample size has often been limited and their results partially contradictory. This study evaluated factors associated with COVID-19 mortality in the population of Madrid over 75 years of age, in infected patients, and in hospitalized patients up to January 2021. PATIENTS AND METHODS: This population-based cohort study analyzed all residents of the Community of Madrid born before January 1, 1945 who were alive as of December 31, 2019. Demographic and clinical data were obtained from primary care electronic medical records (PC-Madrid), data on hospital admissions from the Conjunto Mínimo Básico de Datos (CMBD, Minimum Data Set), and data on mortality from the Índice Nacional de Defunciones (INDEF, National Death Index). Data on SARS-CoV-2 infection, hospitalization, and death were collected from March 1, 2020 to January 31, 2021. RESULTS: A total of 587,603 subjects were included in the cohort. Of them, 41,603 (7.1%) had confirmed SARS-CoV-2 infection, of which 22,362 (53.7% of the infected individuals) were hospitalized and 11,251 (27%) died. Male sex and age were the factors most closely associated with mortality, though many comorbidities also had an influence. The associations were stronger in the analysis of the total population than in the analysis of infected or hospitalized patients. Mortality among hospitalized patients was lower during the second wave (33.4%) than during the first wave (41.2%) of the pandemic. CONCLUSION: Age, sex, and numerous comorbidities are associated with risk of death due to COVID-19. Mortality in hospitalized patients declined notably after the first wave of the pandemic.
Subject(s)
COVID-19 , SARS-CoV-2 , Cohort Studies , Hospitalization , Humans , Male , PandemicsABSTRACT
Objective: Various studies have identified factors associated with risk of mortality in patients with SARS-CoV-2 infection. However, their sample size has often been limited and their results partially contradictory. This study evaluated factors associated with COVID-19 mortality in the population of Madrid over 75 years of age, in infected patients, and in hospitalized patients up to January 2021. Patients and methods: This population-based cohort study analyzed all residents of the Community of Madrid born before January 1, 1945 who were alive as of December 31, 2019. Demographic and clinical data were obtained from primary care electronic medical records (PC-Madrid), data on hospital admissions from the Conjunto Mínimo Básico de Datos (CMBD, Minimum Data Set), and data on mortality from the Índice Nacional de Defunciones (INDEF, National Death Index). Data on SARS-CoV-2 infection, hospitalization, and death were collected from March 1, 2020 to January 31, 2021. Results: A total of 587,603 subjects were included in the cohort. Of them, 41,603 (7.1%) had confirmed SARS-CoV-2 infection, of which 22,362 (53.7% of the infected individuals) were hospitalized and 11,251 (27%) died. Male sex and age were the factors most closely associated with mortality, though many comorbidities also had an influence. The associations were stronger in the analysis of the total population than in the analysis of infected or hospitalized patients. Mortality among hospitalized patients was lower during the second wave (33.4%) than during the first wave (41.2%) of the pandemic. Conclusion: Age, sex, and numerous comorbidities are associated with risk of death due to COVID-19. Mortality in hospitalized patients declined notably after the first wave of the pandemic.
ABSTRACT
To swim up gradients of nutrients, E. coli senses nutrient concentrations within its periplasm. For small nutrient molecules, periplasmic concentrations typically match extracellular concentrations. However, this is not necessarily the case for saccharides, such as maltose, which are transported into the periplasm via a specific porin. Previous observations have shown that, under various conditions, E. coli limits maltoporin abundance so that, for extracellular micromolar concentrations of maltose, there are predicted to be only nanomolar concentrations of free maltose in the periplasm. Thus, in the micromolar regime, the total uptake of maltose from the external environment into the cytoplasm is limited not by the abundance of cytoplasmic transport proteins but by the abundance of maltoporins. Here, we present results from experiments and modeling suggesting that this porin-limited transport enables E. coli to sense micromolar gradients of maltose despite having a high-affinity ABC transport system that is saturated at these micromolar levels. We used microfluidic assays to study chemotaxis of E. coli in various gradients of maltose and methyl-aspartate and leveraged our experimental observations to develop a mechanistic transport-and-sensing chemotaxis model. Incorporating this model into agent-based simulations, we discover a trade-off between uptake and sensing: although high-affinity transport enables higher uptake rates at low nutrient concentrations, it severely limits the range of dynamic sensing. We thus propose that E. coli may limit periplasmic uptake to increase its chemotactic sensitivity, enabling it to use maltose as an environmental cue.
Subject(s)
Escherichia coli Proteins , Periplasmic Binding Proteins , Bacterial Proteins/metabolism , Chemotaxis , Escherichia coli/metabolism , Escherichia coli Proteins/metabolism , Maltose/metabolism , Maltose-Binding Proteins/metabolism , Periplasmic Binding Proteins/metabolism , Porins/metabolismABSTRACT
The capacity of planktonic marine microorganisms to actively seek out and exploit microscale chemical hotspots has been widely theorized to affect ocean-basin scale biogeochemistry1-3, but has never been examined comprehensively in situ among natural microbial communities. Here, using a field-based microfluidic platform to quantify the behavioural responses of marine bacteria and archaea, we observed significant levels of chemotaxis towards microscale hotspots of phytoplankton-derived dissolved organic matter (DOM) at a coastal field site across multiple deployments, spanning several months. Microscale metagenomics revealed that a wide diversity of marine prokaryotes, spanning 27 bacterial and 2 archaeal phyla, displayed chemotaxis towards microscale patches of DOM derived from ten globally distributed phytoplankton species. The distinct DOM composition of each phytoplankton species attracted phylogenetically and functionally discrete populations of bacteria and archaea, with 54% of chemotactic prokaryotes displaying highly specific responses to the DOM derived from only one or two phytoplankton species. Prokaryotes exhibiting chemotaxis towards phytoplankton-derived compounds were significantly enriched in the capacity to transport and metabolize specific phytoplankton-derived chemicals, and displayed enrichment in functions conducive to symbiotic relationships, including genes involved in the production of siderophores, B vitamins and growth-promoting hormones. Our findings demonstrate that the swimming behaviour of natural prokaryotic assemblages is governed by specific chemical cues, which dictate important biogeochemical transformation processes and the establishment of ecological interactions that structure the base of the marine food web.
Subject(s)
Chemotaxis , Microbiota , Bacteria , Dissolved Organic Matter , Oceans and Seas , Phytoplankton/metabolism , Seawater/microbiologyABSTRACT
Immiscible hydrocarbons occur in the ocean water column as droplets of varying diameters. Although microbial oil degradation is a central process in the remediation of hydrocarbon pollution in marine environments, the relationship between droplet size distribution and oil degradation rates by bacteria remains unclear, with a conflicting history of laboratory studies. Despite this knowledge gap, the use of chemical dispersants in oil spill response and mitigation is based on the rationale that increasing the surface-area-to-volume ratio of droplets will enhance net bacterial biodegradation rates. We demonstrate that this intuitive argument does not apply to most natural marine environments, where the abundance of oil droplets is much lower than in laboratory experiments and droplet-bacteria encounters are the limiting factor. We present a mechanistic encounter-consumption model to predict the characteristic time for oil degradation by marine bacteria as a function of the initial oil concentration, the distribution of droplet sizes, and the initial abundance of oil-degrading bacteria. We find that the tradeoff between the encounter time and the consumption time leads to an optimal droplet size larger than the average size generated by the application of dispersants. Reducing droplet size below this optimum can increase the persistence of oil droplets in the environment from weeks to years. The new perspective granted by this biophysical model of biodegradation that explicitly accounts for oil-microbe encounters changes our understanding of biodegradation particularly in the deep ocean, where droplets are often small and oil concentrations low, and explains degradation rate discrepancies between laboratory and field studies.
Subject(s)
Petroleum Pollution , Petroleum , Water Pollutants, Chemical , Bacteria/metabolism , Biodegradation, Environmental , Hydrocarbons/metabolism , Petroleum/metabolism , Petroleum Pollution/analysis , Seawater/microbiology , Water Pollutants, Chemical/analysisABSTRACT
Elevated seawater temperatures have contributed to the rise of coral disease mediated by bacterial pathogens, such as the globally distributed Vibrio coralliilyticus, which utilizes coral mucus as a chemical cue to locate stressed corals. However, the physiological events in the pathogens that follow their entry into the coral host environment remain unknown. Here, we present simultaneous measurements of the behavioral and transcriptional responses of V. coralliilyticus BAA-450 incubated in coral mucus. Video microscopy revealed a strong and rapid chemokinetic behavioral response by the pathogen, characterized by a two-fold increase in average swimming speed within 6 min of coral mucus exposure. RNA sequencing showed that this bacterial behavior was accompanied by an equally rapid differential expression of 53% of the genes in the V. coralliilyticus genome. Specifically, transcript abundance 10 min after mucus exposure showed upregulation of genes involved in quorum sensing, biofilm formation, and nutrient metabolism, and downregulation of flagella synthesis and chemotaxis genes. After 60 min, we observed upregulation of genes associated with virulence, including zinc metalloproteases responsible for causing coral tissue damage and algal symbiont photoinactivation, and secretion systems that may export toxins. Together, our results suggest that V. coralliilyticus employs a suite of behavioral and transcriptional responses to rapidly shift into a distinct infection mode within minutes of exposure to the coral microenvironment.
Subject(s)
Anthozoa , Vibrio , Animals , Chemotaxis , Mucus , Seawater , Vibrio/genetics , VirulenceABSTRACT
Split-thickness skin grafting is a very popular technique of wound closure, especially for large wounds. The success rate of a split-thickness skin graft (STSG) has consistently been in the range of 70-90%. Multiple techniques have been introduced to further improve graft survival, for example, the use of autologous platelet-rich plasma (PRP), thrombin gel, platelet-rich fibrin matrix, and negative pressure wound therapy. We evaluated the impact of PRP use on the survival of STSG through a meta-analysis. We conducted the analysis in accordance with Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) protocol and performed a literature search using the following databases: PubMed, Cochrane, and ClinicalTrials.gov. A total of 126 articles were yielded by the search, out of which four randomized controlled trials (RCTs) were included according to our eligibility criteria and irrelevant articles were excluded. The intervention group received PRP application to the wound bed before applying the graft while the control group received treatment with conventional fixation procedures (sutures and staples). We estimated the pooled odds ratio with a 95% confidence interval (CI). The total number of participants in the analysis was 460. The participants had wounds of varying etiology. Post-operative graft loss and hematoma formation were taken to be the primary and secondary outcome measures, respectively. Thirty-four participants suffered graft loss of differing extent in the control group while three participants suffered graft loss in the intervention group. The pooled odds ratio for graft loss was 0.15 (95% CI: 0.05-0.49; I2=38%; p=0.184) signifying that PRP use decreased the odds of graft loss by 85%. For our secondary outcome measure, 440 participants were studied. Forty-four participants suffered hematoma formation in the control group versus 11 in the intervention group. The pooled odds ratio for hematoma formation was calculated as 0.21 (95% CI: 0.09-0.50; I2=0%; p=0.869) signifying that PRP use decreased the odds of hematoma formation by 79%. PRP appears to significantly impact graft survival, and further studies are needed to strengthen the evidence base for its use in split-thickness skin grafting.
ABSTRACT
Introducción y objetivos: Los programas de rehabilitación cardiaca (PRC) engloban intervenciones encaminadas a mejorar el pronóstico de la enfermedad cardiovascular influyendo en la condición física, mental y social de los pacientes, pero no se conoce su duración óptima. Nuestro objetivo es comparar los resultados de un PRC estándar frente a otro intensivo más breve tras un síndrome coronario agudo, mediante el estudio Más por Menos. Métodos: Diseño prospectivo, aleatorizado, abierto, enmascarado a los evaluadores de eventos y multicéntrico (PROBE). Se aleatorizó a los pacientes al PRC estándar de 8 semanas u otro intensivo de 2 semanas con sesiones de refuerzo. Se realizó una visita final 12 meses después, tras la finalización del programa. Se evaluó: adherencia a la dieta, esfera psicológica, hábito tabáquico, tratamiento farmacológico, capacidad funcional, calidad de vida, parámetros cardiometabólicos y antropométricos, eventos cardiovasculares y mortalidad por cualquier causa durante el seguimiento. Resultados: Se analizó a 497 pacientes (media de edad, 57,8±10,0 años; el 87,3% varones; programa intensivo, n=262; estándar, n=235). Las características basales de ambos grupos eran similares. Al año, más del 93% había mejorado en al menos 1 MET el resultado de la ergometría. Además, la adherencia a la dieta mediterránea y la calidad de vida mejoraron significativamente con el PRC, sin diferencias significativas entre grupos. Los eventos cardiovasculares ocurrieron de manera similar en ambos grupos. Conclusiones: La PRC intensiva podría ser tan efectiva como la PRC estándar en lograr la adherencia a las medidas de prevención secundaria y ser una alternativa para algunos pacientes y centros. (AU)
Introduction and objectives: Cardiac rehabilitation programs (CRP) are a set of interventions to improve the prognosis of cardiovascular disease by influencing patients physical, mental, and social conditions. However, there are no studies evaluating the optimal duration of these programs. We aimed to compare the results of a standard vs a brief intensive CRP in patients after ST-segment elevation and nonST-segment elevation acute coronary syndrome through the Más por Menos study (More Intensive Cardiac Rehabilitation Programs in Less Time). Methods: In this prospective, randomized, open, evaluator-blind for end-point, and multicenter trial (PROBE design), patients were randomly allocated to either standard 8-week CRP or intensive 2-week CRP with booster sessions. A final visit was performed 12 months later, after completion of the program. We assessed adherence to the Mediterranean diet, psychological status, smoking, drug therapy, functional capacity, quality of life, cardiometabolic and anthropometric parameters, cardiovascular events, and all-cause mortality during follow-up. Results: A total of 497 patients (mean age, 57.8±10.0 years; 87.3% men) were finally assessed (intensive: n=262; standard: n=235). Baseline characteristics were similar between the 2 groups. At 12 months, the results of treadmill ergometry improved by ≥ 1 MET in ≥ 93% of the patients. In addition, adherence to the Mediterranean diet and quality of life were significantly improved by CRP, with no significant differences between the groups. The occurrence of cardiovascular events was similar in the 2 groups. Conclusions: Intensive CRP could be as effective as standard CRP in achieving adherence to recommended secondary prevention measures after acute coronary syndrome and could be an alternative for some patients and centers. (AU)
Subject(s)
Humans , Acute Coronary Syndrome , Cardiac Rehabilitation , Diet, Mediterranean , Quality of Life , Secondary PreventionABSTRACT
Marine bacterial diversity is immense and believed to be driven in part by trade-offs in metabolic strategies. Here we consider heterotrophs that rely on organic carbon as an energy source and present a molecular-level model of cell metabolism that explains the dichotomy between copiotrophs-which dominate in carbon-rich environments-and oligotrophs-which dominate in carbon-poor environments-as the consequence of trade-offs between nutrient transport systems. While prototypical copiotrophs, like Vibrios, possess numerous phosphotransferase systems (PTS), prototypical oligotrophs, such as SAR11, lack PTS and rely on ATP-binding cassette (ABC) transporters, which use binding proteins. We develop models of both transport systems and use them in proteome allocation problems to predict the optimal nutrient uptake and metabolic strategy as a function of carbon availability. We derive a Michaelis-Menten approximation of ABC transport, analytically demonstrating how the half-saturation concentration is a function of binding protein abundance. We predict that oligotrophs can attain nanomolar half-saturation concentrations using binding proteins with only micromolar dissociation constants and while closely matching transport and metabolic capacities. However, our model predicts that this requires large periplasms and that the slow diffusion of the binding proteins limits uptake. Thus, binding proteins are critical for oligotrophic survival yet severely constrain growth rates. We propose that this trade-off fundamentally shaped the divergent evolution of oligotrophs and copiotrophs.
Subject(s)
Bacteria/metabolism , Models, Biological , Nutrients/metabolism , Seawater/microbiology , ATP-Binding Cassette Transporters/metabolism , Biological Transport , KineticsABSTRACT
One of the most important worldwide environmental challenges is the alteration of the biogeochemical cycle of phosphorus (P). P is globally exported from terrestrial to aquatic ecosystems, causing the eutrophication of the receiving waters. In this context, magnetic microparticles (MPs) have been recently proposed for trapping P in natural eutrophicated ecosystems, as well as in treated wastewaters. The main advantage of using MPs is that both P and MPs can be recovered from the treated water. Thus, the working hypothesis of the present study is that P can be desorbed from P-loaded MPs and recovered P can be later used as a fertilizer. To test this hypothesis, the best working conditions for desorbing P from P-loaded MPs were identified; then, an experiment with different plant nutrient solutions (neutralized solutions containing recovered P and an unfertilized control) was carried out with three different plant species: Ocimum basilicum L., Cucumis sativus L. and Cucumis melo L. Finally, germination, height, root and shoot biomass and P concentration in root and shoot were compared among treatments. Our results show that the best conditions for P desorption from P-loaded MPs occurred when using 0.1 M NH4OH and using H3PO4 for neutralizing pH. The greenhouse fertirrigation pot experiment showed that the neutralized solution containing desorbed P from P-loaded MPs can be used as a liquid fertilizer, since its combination with macro and microelements significantly increased plant height, growth rate, shoot and root biomass and shoot and root P concentration. As a result, MPs can be proposed to be used for counteracting the widespread and coupled problems of the exhaustion of the P reserves and the eutrophication of aquatic ecosystems.
Subject(s)
Fertilizers , Phosphorus , Biomass , Ecosystem , EutrophicationABSTRACT
INTRODUCTION AND OBJECTIVES: Cardiac rehabilitation programs (CRP) are a set of interventions to improve the prognosis of cardiovascular disease by influencing patients' physical, mental, and social conditions. However, there are no studies evaluating the optimal duration of these programs. We aimed to compare the results of a standard vs a brief intensive CRP in patients after ST-segment elevation and non-ST-segment elevation acute coronary syndrome through the Más por Menos study (More Intensive Cardiac Rehabilitation Programs in Less Time). METHODS: In this prospective, randomized, open, evaluator-blind for end-point, and multicenter trial (PROBE design), patients were randomly allocated to either standard 8-week CRP or intensive 2-week CRP with booster sessions. A final visit was performed 12 months later, after completion of the program. We assessed adherence to the Mediterranean diet, psychological status, smoking, drug therapy, functional capacity, quality of life, cardiometabolic and anthropometric parameters, cardiovascular events, and all-cause mortality during follow-up. RESULTS: A total of 497 patients (mean age, 57.8±10.0 years; 87.3% men) were finally assessed (intensive: n=262; standard: n=235). Baseline characteristics were similar between the 2 groups. At 12 months, the results of treadmill ergometry improved by ≥ 1 MET in ≥ 93% of the patients. In addition, adherence to the Mediterranean diet and quality of life were significantly improved by CRP, with no significant differences between the groups. The occurrence of cardiovascular events was similar in the 2 groups. CONCLUSIONS: Intensive CRP could be as effective as standard CRP in achieving adherence to recommended secondary prevention measures after acute coronary syndrome and could be an alternative for some patients and centers. Registered at ClinicalTrials.gov (Identifier: NCT02619422).
Subject(s)
Acute Coronary Syndrome , Cardiac Rehabilitation , Aged , Feasibility Studies , Female , Humans , Male , Middle Aged , Prospective Studies , Quality of LifeABSTRACT
Laboratory experiments with intact sediment cores from a hypertrophic very windy exposed shallow lake were conducted to assess the combined effect of anoxia and sediment resuspension on phosphorus (P) dynamics after adding different P adsorbents (CFH-12® and Phoslock®). In this study we hypothesize that the addition of geoengineering materials will increase P retention in the sediment even at the worst physic-chemical conditions such as anoxia and sediment resuspension. Both adsorbents significantly reduced the P release from the sediments after a 54 days-anoxic incubation period (CFH-12® by 85% and Phoslock® by 98%) and even after resuspension events (CFH-12® by 84% and Phoslock® by 88%), indicating that both adsorbents are suitable P inactivating agents for restoring shallow eutrophicated lakes under such circumstances. CFH-12® did not release dissolved Fe to the water column neither after the anoxic period nor after resuspension events compared to Control (no adsorbents addition). The La concentration was significantly higher in Phoslock® (3.5-5.7 µg L-1) than in Control at all sampling days but it was not affected by resuspension. The high efficiency in P removal under anoxia and resuspension, the low risk of toxicity and the high maximum adsorption capacity makes CFH-12® a promising adsorbent for lake restoration. Nevertheless, further research about the influence of other factors (i.e. pH, alkalinity, interfering substances or strict anoxia) on the performance of CFH-12® is needed.
Subject(s)
Lakes , Water Pollutants, Chemical , Geologic Sediments , Humans , Hypoxia , Phosphorus , Water Pollutants, Chemical/analysisABSTRACT
Photosynthetic microorganisms are key players in aquatic ecosystems with strong potential for bioenergy production, yet their systematic selection at the single-cell level for improved productivity or stress resilience ("phenotyping") has remained largely inaccessible. To facilitate the phenotyping of microalgae and cyanobacteria, we developed "PhenoChip," a platform for the multiparametric photophysiological characterization and selection of unicellular phenotypes under user-controlled physicochemical conditions. We used PhenoChip to expose single cells of the coral symbiont Symbiodinium to thermal and chemical treatments and monitor single-cell photophysiology via chlorophyll fluorometry. This revealed strain-specific thermal sensitivity thresholds and distinct pH optima for photosynthetic performance, and permitted the identification of single cells with elevated resilience toward rising temperature. Optical expulsion technology was used to collect single cells from PhenoChip, and their propagation revealed indications of transgenerational preservation of photosynthetic phenotypes. PhenoChip represents a versatile platform for the phenotyping of photosynthetic unicells relevant to biotechnology, ecotoxicology, and assisted evolution.
Subject(s)
Anthozoa , Microalgae , Animals , Anthozoa/physiology , Ecosystem , Phenomics , Photosynthesis , SymbiosisABSTRACT
Recent studies have shown that even in the absence of extrinsic stress, the morphologically symmetrically dividing model bacteria Escherichia coli do not generate offspring with equal reproductive fitness. Instead, daughter cells exhibit asymmetric division times that converge to two distinct growth states. This represents a limited senescence/rejuvenation process derived from asymmetric division that is stable for hundreds of generations. It remains unclear why the bacteria do not continue the senescence beyond this asymptote. Although there are inherent fitness benefits for heterogeneity in population growth rates, the two growth equilibria are surprisingly similar, differing by a few percent. In this work we derive an explicit model for the growth of a bacterial population with two growth equilibria, based on a generalized Fibonacci recurrence, in order to quantify the fitness benefit of a limited senescence process and examine costs associated with asymmetry that could generate the observed behavior. We find that a simple saturating effect of asymmetric partitioning of subcellular components is sufficient to explain why two distinct but similar growth states may be optimal while providing evolutionarily significant growth advantages.
Subject(s)
Escherichia coli , Genetic Fitness , BacteriaABSTRACT
Dimethylsulfoniopropionate (DMSP) is a pivotal compound in marine biogeochemical cycles and a key chemical currency in microbial interactions. Marine bacteria transform DMSP via two competing pathways with considerably different biogeochemical implications: demethylation channels sulfur into the microbial food web, whereas cleavage releases sulfur into the atmosphere. Here, we present single-cell measurements of the expression of these two pathways using engineered fluorescent reporter strains of Ruegeria pomeroyi DSS-3, and find that external DMSP concentration dictates the relative expression of the two pathways. DMSP induces an upregulation of both pathways, but only at high concentrations (>1 µM for demethylation; >35 nM for cleavage), characteristic of microscale hotspots such as the vicinity of phytoplankton cells. Co-incubations between DMSP-producing microalgae and bacteria revealed an increase in cleavage pathway expression close to the microalgae's surface. These results indicate that bacterial utilization of microscale DMSP hotspots is an important determinant of the fate of sulfur in the ocean.