RESUMEN
Past and recent applications of 2,4,6-trinitrotoluene (TNT) in military and civilian industries have led to contamination of soil and marine ecosystems. Among various TNT remediation techniques, biological remediation is widely accepted for its sustainability, low cost, and scalable applications. This study was designed to isolate a fungus strain from a TNT-contaminated soil to investigate its tolerance to and potential for removal of TNT. Thus, a soil column with a history of periodic TNT amendment was used to isolate dominant strains of fungi Fusarium solani isolate, which is not commonly reported for TNT mineralization and was found predominant in the subsurface layer of the TNT-amended soil. F. solani was investigated for TNT concentration tolerance at 30, 70, and 100 mg/L on agar plates and for TNT removal in liquid cultures at the same given concentrations. F. solani activity was compared with that of a reference soil-born fungus that has been intensively studied for TNT removal (Phanerochaete chrysosporium) obtained from the American Type Culture Collection. On agar media, F. solani showed a larger colony diameter than P. chrysosporium at similar TNT concentrations, indicating its high potential to tolerate toxic levels of TNT as found in contaminated sites. In the liquid culture medium, F. solani was able to significantly produce higher biomass than P. chrysosporium in all TNT concentrations. The TNT removal percentage from the liquid culture at the highest TNT concentration of 100 mg/L reached about 85% with F. solani, while P. chrysosporium was no better than 25% at the end of an 84-h incubation period. Results indicate a significant potential of using F. solani in the bioremediation of polluted TNT soils that overcome the high concentration barrier in the field. However, further investigation is needed to identify enzymatic potential and the most effective applications and possible limitations of this method on a large scale.
RESUMEN
The second generation energy crop Miscanthus x giganteus (Mxg) was cultivated in pots with mixtures of clean and petroleum industry contaminated soil affected by petroleum, Pb, Zn contamination and high salinity. The survival rate reached 100%, nevertheless the biomass parameters were negatively affected even in the lowest proportion of contaminated soil. In the lowest contamination, where the plant grew still quite successfully, C10-C40 degradation was significantly enhanced compared to the unplanted control with degradation of 58 ± 14%. The plant contribution to aliphatics degradation was significantly correlated with biomass, thus it was negligible in higher contamination. A similar pattern was documented in development of the soil bacterial community. The shift in community structure after Mxg cultivation was observed mainly in the soil with the lowest contaminant proportion, though an increase of bacterial diversity in the miscanthus rhizosphere was observed in all cases. Relative abundance of Actinobacteria was reduced on behalf of several less abundant phyla (Verrucomicrobia, Bacterioides, Acidobacteria). The majority of genera identified as potential petroleum degraders (Pseudomonas, Shinella, Altererythrobacter, Azospirillum, Mesorhizobium, Dyella) were more abundant in contaminated soil with miscanthus, suggesting that Mxg could be a promising crop for phytomanagement of petroleum contaminated soils but salt phytotoxicity needs to be mitigated first.
RESUMEN
Military activities can contaminate productive land with potentially toxic substances. The most common trace metal contaminant on military bases is lead (Pb). A field experiment was begun in 2016 at Fort Riley, KS, in an area with total soil Pb concentrations ranging from 900 to 1,500 mg kg-1 and near-neutral pH. The main objectives were to test the potential of Miscanthus sp. for phytostabilization of the site and to evaluate the effects of soil amendments on Miscanthus growth, soil-plant Pb transfer, bioaccessibility of soil Pb, and soil health. The experimental design was a randomized complete block, with five treatments and four replications. Treatments were (a) existing vegetation; (b) Miscanthus planted in untilled soil, no amendments; (c) Miscanthus planted in tilled soil; (d) Miscanthus planted in tilled soil amended with inorganic P (triple superphosphate applied at 5:3 Pb:P); and (e) Miscanthus planted in tilled soil amended with organic P (Class B biosolids applied at 45 Mg ha-1 ). Tilling and soil amendments increased dry matter yields only in the establishment year. Total Pb uptake, plant tissue Pb concentration, and soil Pb bioaccessibility were significantly less in the Miscanthus plots amended with biosolids than the Miscanthus plots with no added P across all 3 yr. Enzyme activities, organic carbon, and microbial biomass were also greater in biosolids-treated plots. Results show that planting-time addition of soil amendments to Pb-contaminated soil supported Miscanthus establishment, stabilized and reduced bioaccessibility of soil Pb, reduced concentration and uptake of Pb by Miscanthus, and enhanced soil health parameters.
Asunto(s)
Metales Pesados , Personal Militar , Contaminantes del Suelo , Biodegradación Ambiental , Humanos , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisisAsunto(s)
Biocombustibles , Personal Militar , Biomasa , Contaminación Ambiental , Humanos , PoaceaeRESUMEN
This study aims to summarize results on potential phytomanagement of two metal(loid)-polluted military soils using Miscanthus x giganteus. Such an option was tested during 2-year pot experiments with soils taken from former military sites in Sliac, Slovakia and Kamenetz-Podilsky, Ukraine. The following elements were considered: As, Cu, Fe, Mn, Pb, Sr, Ti, Zn and Zr. M. x giganteus showed good growth at both military soils with slightly higher maximum shoot lengths in the second year of vegetation. Based on Principal Component Analysis similarities of metal(loid) uptake by roots, stems and leaves were summarized. Major part of the elements remained in M. x giganteus roots and rather limited amounts moved to the aerial parts. Levels taken up decreased in the second vegetation year. Dynamics of foliar metal(loid) concentrations divided the elements in two groups: essential elements required for metabolism (Fe, Mn, Cu, and Zn) and non-essential elements without any known metabolic need (As, Sr, Ti, and Zr). Fe, Mn, Ti and Sr showed similar S-shaped uptake curve in terms of foliar concentrations (likely due to dilution in growing biomass), while Cu exhibited a clear peak mid-season. Behavior of Zn was in between. Foliar Zr and As concentrations were below detection limit. The results illustrated a good potential of M. x giganteus for safely growing on metal-polluted soils taken from both military localities.
Asunto(s)
Biocombustibles , Restauración y Remediación Ambiental/métodos , Contaminantes del Suelo/análisis , Biodegradación Ambiental , Biomasa , Contaminantes Ambientales/análisis , Metales/análisis , Raíces de Plantas/metabolismo , Poaceae/metabolismo , Eslovaquia , SueloRESUMEN
BACKGROUND: Nurse engagement is a modifiable element of the work environment and has shown promise as a potential safety intervention. PURPOSE: Our study examined the relationship between the level of engagement, staffing, and assessments of patient safety among nurses working in hospital settings. METHODS: A secondary analysis of linked cross-sectional data was conducted using survey data of 26 960 nurses across 599 hospitals in 4 states. Logistic regression models were used to examine the association between nurse engagement, staffing, and nurse assessments of patient safety. RESULTS: Thirty-two percent of nurses gave their hospital a poor or failing patient safety grade. In 25% of hospitals, nurses fell in the least or only somewhat engaged categories. A 1-unit increase in engagement lowered the odds of an unfavorable safety grade by 29% (P < .001). Hospitals where nurses reported higher levels of engagement were 19% (P < .001) less likely to report that mistakes were held against them. Nurses in poorly staffed hospitals were 6% more likely to report that important information about patients "fell through the cracks" when transferring patients across units (P < .001). CONCLUSIONS: Interventions to improve nurse engagement and adequate staffing serve as strategies to improve patient safety.
Asunto(s)
Personal de Enfermería en Hospital/provisión & distribución , Seguridad del Paciente , Admisión y Programación de Personal , Calidad de la Atención de Salud/estadística & datos numéricos , Estudios Transversales , Hospitales , Humanos , Personal de Enfermería en Hospital/psicología , Encuestas y Cuestionarios , Lugar de Trabajo/psicologíaRESUMEN
Constructed wetland treatment systems are used to remove selenium (Se) from flue-gas desulfurization (FGD) wastewater (WW). However, direct confirmation of the mechanism responsible for FGD WW Se retention in soil is lacking. A laboratory-based soil column study was performed to develop an evidence-based mechanism of Se retention and to study the behavior and the retention capacity of FGD WW constituents in water-saturated soil. A deoxygenated 1:1 mixture of FGD WW and raw water was delivered to the columns bottom-up at a flux of 1.68 cm d for 100 d. Some of the columns were flushed with the raw water at the same rate for an additional 100 d. Column effluent was analyzed for constituents of concern. Results showed a complete retention of FGD WW Se in the soil materials. Boron and fluorine were partially retained; however, sulfur, sodium, and chlorine retention was poor, agreeing with field observations. The FGD WW Se was retained in soil near the inlet end of the columns, indicating its limited mobility under reduced conditions. Sequential extraction procedure revealed that retained Se was mainly sequestered as stable/residual forms. Bulk- and micro-X-ray absorption near-edge structure spectroscopy confirmed that Se was mainly retained as reduced/stable species [Se(IV), organic Se, and Se(0)]. This study provides direct evidence for FGD WW Se retention in water-saturated soil via the transformation of oxidized Se into reduced/stable forms.
Asunto(s)
Selenio/química , Aguas Residuales , Purificación del Agua , Selenio/análisis , Suelo , Contaminantes del Suelo , Agua , HumedalesRESUMEN
Members of the multicopper oxidase (MCO) family of enzymes can be classified by their substrate specificity; for example, ferroxidases oxidize ferrous iron, ascorbate oxidases oxidize ascorbate, and laccases oxidize aromatic substrates such as diphenols. Our previous work on an insect multicopper oxidase, MCO1, suggested that it may function as a ferroxidase. This hypothesis was based on three lines of evidence: RNAi-mediated knock down of Drosophila melanogaster MCO1 (DmMCO1) affects iron homeostasis, DmMCO1 has ferroxidase activity, and DmMCO1 has predicted iron binding residues. In our current study, we expanded our focus to include MCO1 from Anopheles gambiae, Tribolium castaneum, and Manduca sexta. We verified that MCO1 orthologs have similar expression profiles, and that the MCO1 protein is located on the basal surface of cells where it is positioned to oxidize substrates in the hemolymph. In addition, we determined that RNAi-mediated knock down of MCO1 in A. gambiae affects iron homeostasis. To further characterize the enzymatic activity of MCO1 orthologs, we purified recombinant MCO1 from all four insect species and performed kinetic analyses using ferrous iron, ascorbate and two diphenols as substrates. We found that all of the MCO1 orthologs are much better at oxidizing ascorbate than they are at oxidizing ferrous iron or diphenols. This result is surprising because ascorbate oxidases are thought to be specific to plants and fungi. An analysis of three predicted iron binding residues in DmMCO1 revealed that they are not required for ferroxidase or laccase activity, but two of the residues (His374 and Asp380) influence oxidation of ascorbate. These two residues are conserved in MCO1 orthologs from insects and crustaceans; therefore, they are likely to be important for MCO1 function. The results of this study suggest that MCO1 orthologs function as ascorbate oxidases and influence iron homeostasis through an unknown mechanism.
Asunto(s)
Anopheles/enzimología , Ascorbato Oxidasa/metabolismo , Proteínas de Insectos/metabolismo , Manduca/enzimología , Tribolium/enzimología , Secuencia de Aminoácidos , Animales , Ácido Ascórbico/química , Ceruloplasmina/química , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Compuestos Ferrosos/química , Hemolinfa/enzimología , Proteínas de Insectos/genética , Cinética , Datos de Secuencia Molecular , Oxidación-Reducción , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Alineación de Secuencia , Especificidad de la Especie , Especificidad por SustratoRESUMEN
BACKGROUND: Up to 30% of acute stroke evaluations are deemed stroke mimics (SM). As telestroke consultation expands across the world, increasing numbers of SM patients are likely being evaluated via Telestroke. We developed a model to prospectively identify ischemic SMs during Telestroke evaluation. METHODS AND RESULTS: We analyzed 829 consecutive patients from January 2004 to April 2013 in our internal New England-based Partners TeleStroke Network for a derivation cohort, and 332 cases for internal validation. External validation was performed on 226 cases from January 2008 to August 2012 in the Partners National TeleStroke Network. A predictive score was developed using stepwise logistic regression, and its performance was assessed using receiver-operating characteristic (ROC) curve analysis. There were 23% SM in the derivation, 24% in the internal, and 22% in external validation cohorts based on final clinical diagnosis. Compared to those with ischemic cerebrovascular disease (iCVD), SM had lower mean age, fewer vascular risk factors, more frequent prior seizure, and a different profile of presenting symptoms. The TeleStroke Mimic Score (TM-Score) was based on factors independently associated with SM status including age, medical history (atrial fibrillation, hypertension, seizures), facial weakness, and National Institutes of Health Stroke Scale >14. The TM-Score performed well on ROC curve analysis (derivation cohort AUC=0.75, internal validation AUC=0.71, external validation AUC=0.77). CONCLUSIONS: SMs differ substantially from their iCVD counterparts in their vascular risk profiles and other characteristics. Decision-support tools based on predictive models, such as our TM Score, may help clinicians consider alternate diagnosis and potentially detect SMs during complex, time-critical telestroke evaluations.
Asunto(s)
Técnicas de Apoyo para la Decisión , Accidente Cerebrovascular/diagnóstico , Telemedicina/métodos , Anciano , Isquemia Encefálica/diagnóstico , Femenino , Humanos , Masculino , Modelos Estadísticos , Estudios Prospectivos , Reproducibilidad de los ResultadosRESUMEN
PURPOSE: The value of the Medical Student Performance Evaluation (MSPE) for a program director is in the information it contains comparing how a student performed in medical school relative to his or her classmates. The Association of American Medical Colleges has recommended that a student's class ranking be included in the summary paragraph of the MSPE and that this information be repeated in a supplementary appendix. METHODS: The authors reviewed the MSPEs from 1,479 applications for residency training positions. The aim was to determine to what extent and in what manner individual schools reveal how their students perform relative to their peers. The authors then set out to create a database containing this information. RESULTS: Working from a list of 141 US members of the Association of American Medical Colleges, complete information for 107 schools (76%) and partial information for the remaining 34 schools (24%) was gathered. Only 12 schools (9%) included complete comparative information in the summary section in accordance with the guidelines of the Association of American Medical Colleges. Other schools were in partial compliance or did not comply at all. The database the authors constructed will inform users if comparative information is available, guide users to its location in the MSPE, and explain the meaning of the language different schools use to rank or classify their students. CONCLUSIONS: The authors recognize that this database is incomplete and that the individual institutions will alter their ranking system from time to time. But this database is offered in an open format so that it can be continuously updated by users.
Asunto(s)
Bases de Datos Factuales , Educación de Postgrado en Medicina/estadística & datos numéricos , Evaluación Educacional/métodos , Evaluación Educacional/estadística & datos numéricos , Docentes Médicos/estadística & datos numéricos , Estudiantes de Medicina/clasificación , Estudiantes de Medicina/estadística & datos numéricos , Liderazgo , New York , Estados UnidosRESUMEN
In a move to emphasize the educational outcomes of training programs, the ACGME has created the Next Accreditation System (NAS). The stated goals of NAS include aiding the ACGME in the accreditation of programs based on educational outcome measures, decreasing program burdens associated with the conventional process-based approach to ACGME accreditation, allowing good programs to innovate while enabling struggling programs to steadily improve, and providing public accountability for outcomes. Diagnostic radiology is among the first group of specialties to undergo NAS implementation and began operating under the NAS in July 2013. This article describes the various components of the NAS and explains the new elements, including the clinical learning environment review program, the milestones, the clinical competency committee, and the self-study visits.
Asunto(s)
Acreditación/normas , Competencia Clínica/normas , Educación Basada en Competencias/normas , Evaluación Educacional/normas , Internado y Residencia/normas , Radiología/educación , Radiología/normas , Evaluación de Programas y Proyectos de Salud/normas , Estados UnidosRESUMEN
In vitro studies suggest that the intracellular C terminus of Neuroligin1 (NL1) could play a central role in the maturation of excitatory synapses. However, it is unknown how this activity affects synapses in vivo, and whether it may impact the development of complex behaviors. To determine how NL1 influences the state of glutamatergic synapses in vivo, we compared the synaptic and behavioral phenotypes of mice overexpressing a full-length version of NL1 (NL1FL) with mice overexpressing a version missing part of the intracellular domain (NL1ΔC). We show that overexpression of full-length NL1 yielded an increase in the proportion of synapses with mature characteristics and impaired learning and flexibility. In contrast, the overexpression of NL1ΔC increased the number of excitatory postsynaptic structures and led to enhanced flexibility in mnemonic and social behaviors. Transient overexpression of NL1FL revealed that elevated levels are not necessary to maintain synaptic and behavioral states altered earlier in development. In contrast, overexpression of NL1FL in the fully mature adult was able to impair normal learning behavior after 1 month of expression. These results provide the first evidence that NL1 significantly impacts key developmental processes that permanently shape circuit function and behavior, as well as the function of fully developed neural circuits. Overall, these manipulations of NL1 function illuminate the significance of NL1 intracellular signaling in vivo, and enhance our understanding of the factors that gate the maturation of glutamatergic synapses and complex behavior. This has significant implications for our ability to address disorders such as autism spectrum disorders.
Asunto(s)
Conducta Animal/fisiología , Moléculas de Adhesión Celular Neuronal/fisiología , Sistemas de Mensajero Secundario/fisiología , Sinapsis/fisiología , Animales , Corteza Auditiva/crecimiento & desarrollo , Corteza Auditiva/fisiología , Western Blotting , Moléculas de Adhesión Celular Neuronal/genética , Espinas Dendríticas/fisiología , Espinas Dendríticas/ultraestructura , Doxiciclina/farmacología , Fenómenos Electrofisiológicos , Proteínas Fluorescentes Verdes , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Discapacidades para el Aprendizaje/genética , Discapacidades para el Aprendizaje/psicología , Aprendizaje por Laberinto/fisiología , Ratones , Ratones Transgénicos , Microscopía Confocal , Desempeño Psicomotor/efectos de los fármacos , Desempeño Psicomotor/fisiología , Reconocimiento en Psicología , Conducta Social , Predominio Social , Sinaptosomas/fisiologíaRESUMEN
PURPOSE: Temporary tissue expanders (TTE) with an internal magnetic metal port (IMP) have been increasingly used for breast reconstruction in post-mastectomy patients who receive radiation therapy (XRT). We evaluated XRT plans of patients with IMP to determine its effect on XRT dose distribution. METHODS AND MATERIALS: Original treatment plans with CT simulation scans of 24 consecutive patients who received XRT (ORI), planned without heterogeneity corrections, to a reconstructed breast containing an IMP were used. Two additional treatment plans were then generated: one treatment plan with the IMP assigned the electron density of the rare earth magnet, nickel plated neodymium-iron-boron (HET), and a second treatment plan with the IMP assigned a CT value of 1 to simulate a homogeneous breast without an IMP (BRS). All plans were prescribed 50 Gy to the reconstructed breast (CTV). RESULTS: CTV coverage by 50 Gy was significantly lower in the HET (mean 87.7% CTV) than in either the ORI (mean 99.7% CTV, P<.001) or BRS plans (mean 95.0% CTV, P<.001). The effect of the port was more pronounced on CT slices containing the IMP with prescription dose coverage of the CTV being less in the HET than in either ORI (mean difference 33.6%, P<.01) or BRS plans (mean difference 30.1%, P<.001). HET had a less homogeneous and conformal dose distribution than BRS or ORI. CONCLUSION: IMPs increase dose heterogeneity and reduce dose to the breast CTV through attenuation of the beam. For optimal XRT treatment, heterogeneity corrections should be used in XRT planning for patients with TTE with IMP, as the IMP impacts dose distribution.
Asunto(s)
Neoplasias de la Mama/radioterapia , Mamoplastia/instrumentación , Dispositivos de Expansión Tisular , Adulto , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mastectomía , Metales , Persona de Mediana Edad , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodosRESUMEN
PURPOSE: The indications for upfront laryngectomy in the management of laryngeal cancer are a functionless larynx and extralaryngeal extension. Practically, clinicians rely on imaging to predict which patients will have T4 disease. Our goal was to review the accuracy of preoperative computed tomography (CT) scanning in determining the necessity for initial laryngectomy for advanced laryngeal cancer. PATIENTS AND METHODS: In total, 107 consecutive untreated laryngectomy specimens with high-quality, preoperative CT imaging interpreted by our neuroradiologists were reviewed. Radiographic findings, including sclerosis, invasion, penetration, extralaryngeal spread, and subglottic extension were correlated with pathologic findings. CT images were not reinterpreted, since our purpose was to assess the original interpretations. RESULTS: CT imaging reported 23 cases of thyroid cartilage penetration and 27 cases of extralaryngeal spread. Pathology reported 12 cases of thyroid cartilage invasion, 29 cases of penetration, and 45 cases of extralaryngeal disease. CT imaging identified 17 (59%) of 29 cases of pathologically documented thyroid cartilage penetration and 22 (49%) of 45 cases of pathologically documented extralaryngeal spread. Pathologically proven extralaryngeal spread without thyroid cartilage penetration occurred in 18 (40%) of 45 cases. The positive predictive values for thyroid cartilage penetration and extralaryngeal spread were 74% and 81%. Sclerosis was of limited value in predicting thyroid cartilage invasion or penetration. Cricoid or arytenoid destruction predicted for thyroid cartilage penetration at rates of 57% and 63%. CONCLUSION: CT imaging has clear limitations when deciding whether there is thyroid cartilage penetration or extralaryngeal spread of advanced laryngeal cancer. Extralaryngeal spread without thyroid cartilage penetration was more common than expected. Alternate methods of pretreatment assessment are needed.
Asunto(s)
Cartílagos Laríngeos/diagnóstico por imagen , Neoplasias Laríngeas/diagnóstico por imagen , Neoplasias Laríngeas/cirugía , Laringectomía , Selección de Paciente , Tomografía Computarizada por Rayos X , Humanos , Cartílagos Laríngeos/patología , Neoplasias Laríngeas/patología , Invasividad Neoplásica , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , EsclerosisRESUMEN
PURPOSE: To evaluate if automatic atlas-based lymph node segmentation (LNS) improves efficiency and decreases inter-observer variability while maintaining accuracy. METHODS AND MATERIALS: Five physicians with head-and-neck IMRT experience used computed tomography (CT) data from 5 patients to create bilateral neck clinical target volumes covering specified nodal levels. A second contour set was automatically generated using a commercially available atlas. Physicians modified the automatic contours to make them acceptable for treatment planning. To assess contour variability, the Simultaneous Truth and Performance Level Estimation (STAPLE) algorithm was used to take collections of contours and calculate a probabilistic estimate of the "true" segmentation. Differences between the manual, automatic, and automatic-modified (AM) contours were analyzed using multiple metrics. RESULTS: Compared with the "true" segmentation created from manual contours, the automatic contours had a high degree of accuracy, with sensitivity, Dice similarity coefficient, and mean/max surface disagreement values comparable to the average manual contour (86%, 76%, 3.3/17.4 mm automatic vs. 73%, 79%, 2.8/17 mm manual). The AM group was more consistent than the manual group for multiple metrics, most notably reducing the range of contour volume (106-430 mL manual vs. 176-347 mL AM) and percent false positivity (1-37% manual vs. 1-7% AM). Average contouring time savings with the automatic segmentation was 11.5 min per patient, a 35% reduction. CONCLUSIONS: Using the STAPLE algorithm to generate "true" contours from multiple physician contours, we demonstrated that, in comparison with manual segmentation, atlas-based automatic LNS for head-and-neck cancer is accurate, efficient, and reduces interobserver variability.