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We used diffusive gradients in thin films (DGT) to measure potentially bioavailable metals in coastal plain streams in the southeastern USA that exhibited strong to moderate blackwater characteristics. Metals were partitioned into particulate metals, DGT-inert metals (i.e., colloidal and refractory organic complexes not accumulated by DGT), and DGT-labile metals (i.e., free metal ions, small inorganic complexes, and labile organic complexes). We also examined the influence of different DGT deployment times using data collected from the field and a follow-up laboratory study. The DGT-measured fraction of dissolved metals in the streams was 15% for Cd, 21% for Zn, 33% for Cu, 37% for Pb, and 98% for Mn. Metals bound to particulates predominated only for Pb. Most of the Cd, Pb, Zn, and Cu were associated with colloids, refractory organic complexes, or particles. Relatively small amounts were in free ion or labile complexes likely to be bioavailable through respiratory surfaces. Modeled concentrations of free and inorganically bound Cu and Pb were lower than the DGT fraction indicating that DGT accumulated some organically bound Cu and Pb that might not have been bioavailable. DGT-exposure times in excess of 5 days may have contributed to the accumulation of partly labile organic-metal complexes and were associated with substantial biofouling that caused metal uptake by DGT to depart from linearity.
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Ríos , Contaminantes Químicos del Agua , Difusión , Monitoreo del Ambiente , Metales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
This paper proposes a new natural language processing (NLP) application for identifying medical jargon terms potentially difficult for patients to comprehend from electronic health record (EHR) notes. We first present a novel and publicly available dataset with expert-annotated medical jargon terms from 18K+ EHR note sentences (MedJ). Then, we introduce a novel medical jargon extraction (MedJEx) model which has been shown to outperform existing state-of-the-art NLP models. First, MedJEx improved the overall performance when it was trained on an auxiliary Wikipedia hyperlink span dataset, where hyperlink spans provide additional Wikipedia articles to explain the spans (or terms), and then fine-tuned on the annotated MedJ data. Secondly, we found that a contextualized masked language model score was beneficial for detecting domain-specific unfamiliar jargon terms. Moreover, our results show that training on the auxiliary Wikipedia hyperlink span datasets improved six out of eight biomedical named entity recognition benchmark datasets. Both MedJ and MedJEx are publicly available.
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We evaluated the ability of diffusive gradients in thin films (DGT) to assess the effects of water hardness and dissolved organic carbon (DOC consisting of humic acids) on Cu and Zn toxicity (i.e., 48â¯h LC50s) to Ceriodaphnia dubia. When DOC was high, Cu concentrations measured by DGT (DGT Cu) were significantly lower than Cu concentrations in water (dissolved Cu), and DGT LC50s were significantly lower than LC50s based on dissolved concentrations. When DOC was low, differences between dissolved Cu and DGT Cu were small, as were differences between dissolved LC50s and DGT LC50s. Differences between DGT and dissolved measurements of Zn were small compared with the differences observed for Cu, and DGT Zn LC50s were relatively similar to dissolved Zn LC50s. Humic acids formed strong organic-Cu complexes that were both inaccessible for biological uptake and excluded by DGT, which selected for free or weakly bound Cu. In contrast, Zn did not form strong complexes with DOC that greatly affected either toxicity or the measurement of Zn by DGT. The effects of hardness on DGT measurements of Cu and Zn were smaller and more complex than the effects of DOC. Large, statistically significant differences between DGT measurements of Cu in low and high DOC water accurately reflected the strong effects of DOC on Cu toxicity. However, the effects of DOC were inconsistent for Zn, and DGT provided less information about the toxic fraction of this metal.
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Cladóceros/fisiología , Metales/toxicidad , Contaminantes Químicos del Agua/toxicidad , Agua/química , Animales , Metales/química , Pruebas de Toxicidad , Contaminantes Químicos del Agua/químicaRESUMEN
OBJECTIVE: Systematic reviews and meta-analyses (SRMAs) rely upon comprehensive searches into diverse resources that catalog primary studies. However, since what constitutes a comprehensive search is unclear, we examined trends in databases searched from 2005-2016, surrounding the publication of search guidelines in 2013, and associations between resources searched and evidence of publication bias in SRMAs involving human subjects. STUDY DESIGN: To ensure comparability of included SRMAs over the 12 years in the face of a near 100-fold increase of international SRMAs (mainly genetic studies from China) during this period, we focused on USA-affiliated SRMAs, manually reviewing 100 randomly selected SRMAs from those published in each year. After excluding articles (mainly for inadequate detail or out-of-scope methods), we identified factors associated with the databases searched, used network analysis to see which resources were simultaneously searched, and used logistic regression to link information sources searched with a lower chance of finding publication bias. RESULTS: Among 817 SRMA articles studied, the common resources used were Medline (95%), EMBASE (44%), and Cochrane (41%). Methods journal SRMAs were most likely to use registries and grey literature resources. We found substantial co-searching of resources with only published materials, and not complemented by searches of registries and the grey literature. The 2013 guideline did not substantially increase searching of registries and grey literature resources to retrieve primary studies for the SRMAs. When used to augment Medline, Scopus (in all SRMAs) and ClinicalTrials.gov (in SRMAs with safety outcomes) were negatively associated with publication bias. CONCLUSIONS: Even SRMAs that search multiple sources tend to search similar resources. Our study supports searching Scopus and CTG in addition to Medline to reduce the chance of publication bias.
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Metaanálisis como Asunto , Proyectos de Investigación/normas , Revisiones Sistemáticas como Asunto , Sesgo , Humanos , Sesgo de PublicaciónRESUMEN
Sources of fecal coliform pollution in a small South Carolina (USA) watershed were identified using inexpensive methods and commonly available equipment. Samples from the upper reaches of the watershed were analyzed with 3M(™) Petrifilm(™) count plates. We were able to narrow down the study's focus to one particular tributary, Sand River, that was the major contributor of the coliform pollution (both fecal and total) to a downstream reservoir that is heavily used for recreation purposes. Concentrations of total coliforms ranged from 2,400 to 120,333 cfu/100 mL, with sharp increases in coliform counts observed in samples taken after rain events. Positive correlations between turbidity and fecal coliform counts suggested a relationship between fecal pollution and stormwater runoff. Antibiotic resistance analysis (ARA) compared antibiotic resistance profiles of fecal coliform isolates from the stream to those of a watershed-specific fecal source library (equine, waterfowl, canines, and untreated sewage). Known fecal source isolates and unknown isolates from the stream were exposed to six antibiotics at three concentrations each. Discriminant analysis grouped known isolates with an overall average rate of correct classification (ARCC) of 84.3 %. A total of 401 isolates from the first stream location were classified as equine (45.9 %), sewage (39.4 %), waterfowl (6.2 %), and feline (8.5 %). A similar pattern was observed at the second sampling location, with 42.6 % equine, 45.2 % sewage, 2.8 % waterfowl, 0.6 % canine, and 8.8 % feline. While there were slight weather-dependent differences, the vast majority of the coliform pollution in this stream appeared to be from two sources, equine and sewage. This information will contribute to better land use decisions and further justify implementation of low-impact development practices within this urban watershed.
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Farmacorresistencia Microbiana/genética , Monitoreo del Ambiente , Ríos/microbiología , Aguas del Alcantarillado/análisis , Microbiología del Agua , Animales , Antibacterianos/farmacología , Recuento de Colonia Microbiana/instrumentación , Recuento de Colonia Microbiana/métodos , Recreación , Ríos/química , Aguas del Alcantarillado/estadística & datos numéricos , South CarolinaRESUMEN
AIM: The goal of this systematic review was to identify moderators of naltrexone efficacy in the treatment of alcohol dependence. METHODS: We searched Pubmed, CINHAL, Embase, PsycINFO and the Cochrane Library from 1990 to April 2012 and reference lists of pertinent review articles, which yielded 622 trial, pooled analysis and review articles. Using pre-established eligibility criteria, two reviewers independently determined whether abstracts contained evidence of demographic or biological characteristics, i.e. moderators, influencing naltrexone response in alcohol dependence. We assessed each publication for risk of bias and evaluated the strength of the body of evidence for each moderator. RESULTS: Twenty-eight publications (on 20 studies) met criteria for data synthesis. These included 26 publications from 12 randomized, placebo-controlled trials, three non-randomized, non-placebo studies and one randomized, non-placebo study. In addition, there were two publications from pooled analyses of four randomized, placebo-controlled trials. Family history of alcohol problems and the Asn40Asp polymorphism of the µ-opioid receptor gene showed a positive association with efficacy in four of five and three of five studies, respectively. Other moderators reported to be associated with efficacy included male sex (two of five studies), pre-treatment drinking (two of two studies) and high craving (two of five studies). However, the overall risk of bias in the published literature is high. CONCLUSIONS: The identification of naltrexone-responsive alcohol-dependent patients is still in development. Studies to date point to two potential moderators-family history and presence of the OPRM1 Asn40Asp polymorphism-as having the strongest evidence. However, the data to date is still insufficient to recommend that any moderator be used in determining clinical treatment.
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Alcoholismo/tratamiento farmacológico , Naltrexona/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico , Humanos , Resultado del TratamientoAsunto(s)
Enfermedades Cardiovasculares/clasificación , Enfermedades Cardiovasculares/epidemiología , American Heart Association , Enfermedades Cardiovasculares/diagnóstico , Femenino , Humanos , Masculino , Grupos Raciales , Medición de Riesgo , Factores Sexuales , Factores de Tiempo , Estados UnidosRESUMEN
The perceptions and religious beliefs held by family members, mental health and health care professionals, and the community may affect the treatment of individuals with schizophrenia. To better identify and understand the influence of families, professionals and community members on individual's treatment for schizophrenia, this review paper examines: (1) the religious perceptions of families, professionals, and the public towards schizophrenia; (2) religious perceptions of the etiology of schizophrenia; (3) how others perceive religion as a coping mechanism; and (4) how religion influences treatment engagement and help-seeking behaviors. MEDLINE and PsycInfo databases were systematically searched from 1980 to 2010 using the terms schizophrenia, schizoaffective, schizophreniform, psychotic disorder not otherwise specified and religion, religiosity, spirituality, and faith. Forty-three (n = 43) original research studies met the inclusion criteria. This study found that religious beliefs influence the treatment of schizophrenia in the following ways: Religious themes were positively associated with coping, treatment engagement and help-seeking behavior. Evidence of religious underpinnings was found in perceptions of etiology. The findings also indicate that there is often both a preference among family members and caregivers to utilize religious-based professionals and caution toward mental health professionals. Researchers and professionals may find avenues for improving treatment through examining the interaction of religious and schizophrenia at the social support level.
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Familia/psicología , Conocimientos, Actitudes y Práctica en Salud , Servicios de Salud Mental/estadística & datos numéricos , Religión , Esquizofrenia/terapia , Apoyo Social , Adulto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Family medicine providers at a large family medicine clinic were surveyed regarding their impression of the impact, utility and safety of the Primary Care Prescribing Psychologist (PCPP) model in which a prescribing psychologist is embedded in a primary care clinic. This article describes the model and provides indications of its strengths and weaknesses as reported by medical providers who have utilized the model for the past 2 years. A brief history of prescribing psychology and the challenges surrounding granting psychologists the authority to prescribe psychotropic medication is summarized. Results indicate family medicine providers agree that having a prescribing psychologist embedded in the family medicine clinic is helpful to their practice, safe for patients, convenient for providers and for patients, and improves patient care. Potential benefits of integrating prescribing psychology into primary care are considered and directions for future research are discussed.
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Prestación Integrada de Atención de Salud , Prescripciones de Medicamentos , Trastornos Mentales/tratamiento farmacológico , Atención Primaria de Salud/organización & administración , Autonomía Profesional , Psicología Clínica/organización & administración , Actitud del Personal de Salud , Medicina Familiar y Comunitaria , Encuestas de Atención de la Salud , Necesidades y Demandas de Servicios de Salud , Humanos , Medicina Militar , Modelos Organizacionales , Grupo de Atención al Paciente , Seguridad del Paciente , Estados UnidosRESUMEN
Telehealth has been touted as one solution to the shortage of mental health providers within the military. Despite developing evidence for the equivalence of telehealth mental health care, there is no research that covers the use of telehealth for population mental health screening, a standard component of postdeployment medical screening. This paper summarizes soldier perceptions of three separate screening events in which telehealth was used and the cost-effectiveness of telehealth versus in-person implementations of the same screening. Soldiers who have not been through telehealth screening report a strong preference for in-person screening. Soldiers who have been through telehealth screening still report preference for in-person screening, but they express more ambivalence about the screening method. Using telehealth-only mental health screening for large numbers of soldiers within a compressed time frame is more expensive than in-person screening. Telehealth resulted in higher referral rates than in-person screening. Government and military leaders should use care when making decisions about telehealth implementation. Although telehealth for small numbers may be sufficiently equivalent and economical, there is no evidence of cost savings or improved acceptability for telehealth mental health post-deployment screening.
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Tamizaje Masivo/métodos , Trastornos Mentales/diagnóstico , Personal Militar/psicología , Telemedicina , Análisis Costo-Beneficio , Humanos , Aceptación de la Atención de Salud , Satisfacción del Paciente , Relaciones Profesional-Paciente , Derivación y Consulta , Estudios Retrospectivos , Telemedicina/economía , Telemedicina/métodosRESUMEN
The Global War on Terrorism and its corresponding frequent and long deployments have resulted in an increase in mental health concerns among active duty troops. To mitigate these impacts, the Department of Defense has implemented postdeployment screening initiatives designed to identify symptomatic soldiers and refer them for mental health care. Although the primary purpose of these screenings is to identify and provide assistance to individuals, macrolevel reporting of screening results for groups can assist Commanders, who are charged with ensuring the wellbeing of their soldiers, to make unit-level interventions. This study assesses the utility of a metatheory of occupational stress, the Soldier Adaptation Model, in organizing feedback information provided to Army Commanders on their units' postdeployment screening results. The results of a combat brigade of 2319 soldiers who completed post-deployment screening following return from Iraq were analyzed using Structural Equation Modeling to assess the Soldier Adaptation Model's use for macrolevel reporting. Results indicate the Soldier Adaptation Model did not strengthen the macrolevel reporting; however, alcohol use and reckless driving were found to mediate the relationship between combat exposure and numerous mental health symptoms and disorders (e.g., post-traumatic stress disorder, anger, depression, anxiety, etc.). Research and practice implications are discussed.
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Adaptación Psicológica , Tamizaje Masivo , Medicina Militar , Personal Militar/psicología , Trastornos por Estrés Postraumático/epidemiología , Adulto , Consumo de Bebidas Alcohólicas , Algoritmos , Ansiedad/epidemiología , Conducción de Automóvil , Depresión/epidemiología , Femenino , Humanos , Irak , Masculino , Trastornos Mentales/epidemiología , Servicios de Salud Mental , Personal Militar/estadística & datos numéricos , Asunción de Riesgos , Encuestas y Cuestionarios , Estados Unidos/epidemiología , GuerraRESUMEN
Groundwater quality effects from septic tanks were investigated in the Woodville Karst Plain, an area that contains numerous sinkholes and a thin veneer of sands and clays overlying the Upper Floridan aquifer (UFA). Concerns have emerged about elevated nitrate concentrations in the UFA, which is the source of water supply in this area of northern Florida. At three sites during dry and wet periods in 2007-2008, water samples were collected from the septic tank, shallow and deep lysimeters, and drainfield and background wells in the UFA and analyzed for multiple chemical indicators including nutrients, nitrate isotopes, organic wastewater compounds (OWCs), pharmaceutical compounds, and microbiological indicators (bacteria and viruses). Median NO3-N concentration in groundwater beneath the septic tank drainfields was 20 mg L(-1) (8.0-26 mg L(-1)). After adjusting for dilution, about 25 to 40% N loss (from denitrification, ammonium sorption, and ammonia volatilization) occurs as septic tank effluent moves through the unsaturated zone to the water table. Nitrogen loading rates to groundwater were highly variable at each site (3.9-12 kg N yr(-1)), as were N and chloride depth profiles in the unsaturated zone. Most OWCs and pharmaceutical compounds were highly attenuated beneath the drainfields; however, five Cs (caffeine, 1,7-dimethylxanthine, phenol, galaxolide, and tris(dichloroisotopropyl)phosphate) and two pharmaceutical compounds (acetaminophen and sulfamethoxazole) were detected in groundwater samples. Indicator bacteria and human enteric viruses were detected in septic tank effluent samples but only intermittently in soil water and groundwater. Contaminant movement to groundwater beneath each septic tank system also was related to water use and differences in lithology at each site.
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Contaminantes del Suelo/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Agua/química , Nitratos/química , Nitrógeno/química , Preparaciones Farmacéuticas , Compuestos de Amonio Cuaternario/química , Ingeniería Sanitaria , Suelo/análisisRESUMEN
Up to 40% of patients with mild haemophilia A have a discrepancy whereby factor VIII (FVIII) measurements by a two-stage chromogenic assay (FVIII:C(CH)) are disproportionately reduced compared with the FVIII one-stage clotting value (FVIII:C). Which assay best reflects the coagulation potential and clinical phenotype in this patient group is of clinical significance, yet remains unclear. We have assessed the global coagulant ability of haemophilia patients with FVIII assay discrepancy using calibrated automated thrombography (CAT). A total of 18 patients with mutations Arg531His/Cys or Arg698Trp causing FVIII discrepancy were investigated, together with 12 haemophilia patients with concordant FVIII values and 15 normal controls. Factor VIII levels in all patients and controls were measured using both one-stage clotting assay and two-stage chromogenic assay. Thrombin generation was assessed in platelet-poor plasma by CAT using a low tissue factor concentration (1 pm). FVIII:C(CH) values were below normal in all patients, and in the discrepant group were between 1.5- and 8-fold lower than FVIII:C values. CAT parameters were affected in all haemophilia patients. The endogenous thrombin potential (ETP) was reduced to 58-67% of the mean normal value (1301 nm min(-1)), whereas peak thrombin was further reduced to 27-30% of the mean normal value (178 nm) in both discrepant and concordant patient groups. Analysis of the discrepant patient group showed the most significant correlation between the one-stage FVIII:C assay and ETP (r(2) = 0.44) and peak thrombin parameters (r(2) = 0.27).
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Factor VIII/análisis , Hemofilia A/sangre , Hemofilia A/genética , Mutación , Trombina/biosíntesis , Adolescente , Adulto , Pruebas de Coagulación Sanguínea/métodos , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Tromboelastografía , Adulto JovenRESUMEN
OBJECTIVE: To assess the effect on risk-adjustment of inpatient mortality rates of progressively enhancing administrative claims data with clinical data that are increasingly expensive to obtain. Data Sources. Claims and abstracted clinical data on patients hospitalized for 5 medical conditions and 3 surgical procedures at 188 Pennsylvania hospitals from July 2000 through June 2003. METHODS: Risk-adjustment models for inpatient mortality were derived using claims data with secondary diagnoses limited to conditions unlikely to be hospital-acquired complications. Models were enhanced with one or more of 1) secondary diagnoses inferred from clinical data to have been present-on-admission (POA), 2) secondary diagnoses not coded on claims but documented in medical records as POA, 3) numerical laboratory results from the first hospital day, and 4) all available clinical data from the first hospital day. Alternative models were compared using c-statistics, the magnitude of errors in prediction for individual cases, and the percentage of hospitals with aggregate errors in prediction exceeding specified thresholds. RESULTS: More complete coding of a few under-reported secondary diagnoses and adding numerical laboratory results to claims data substantially improved predictions of inpatient mortality. Little improvement resulted from increasing the maximum number of available secondary diagnoses or adding additional clinical data. CONCLUSIONS: Increasing the completeness and consistency of reporting a few secondary diagnosis codes for findings POA and merging claims data with numerical laboratory values improved risk adjustment of inpatient mortality rates. Expensive abstraction of additional clinical information from medical records resulted in little further improvement.
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Diagnóstico , Mortalidad Hospitalaria , Clasificación Internacional de Enfermedades , Evaluación de Resultado en la Atención de Salud/métodos , Ajuste de Riesgo , Sistemas de Información en Laboratorio Clínico , Humanos , Formulario de Reclamación de Seguro , Modelos Estadísticos , Pennsylvania , Indicadores de Calidad de la Atención de SaludRESUMEN
The benefits of psychotherapy have been well documented; however, 5-10% of clients worsen while in treatment and another minority shows no response. The effects of feedback timing (delayed or immediate) and type (progress feedback and Clinical Support Tool [CST] feedback), aimed at reducing deterioration and improving outcomes, were examined in a sample of 1101 clients whose outcome was contrasted across experimental groups and with two archival groups: a delayed progress feedback and CST feedback group (n = 1374) and a treatment-as-usual control group (n = 1445). Progress feedback to therapists improved outcomes, especially for cases at risk for a negative outcome, but direct progress feedback to clients did not. Effects were significantly enhanced by using the manual-based CST. There were no significant differences in outcome between the 1-week-delayed CST feedback and 2-week-delayed CST feedback groups; however, clients in the week-delayed CST feedback timing condition attended three less sessions, on average, than their 2-week-delayed CST feedback counterparts while maintaining similar treatment gains. Results were interpreted as supporting the value of monitoring client progress and feeding back this information to therapists as well as assisting therapists in problem solving with cases at risk for treatment failure.
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Toma de Decisiones Asistida por Computador , Retroalimentación , Evaluación de Resultado en la Atención de Salud/métodos , Psicoterapia , Adulto , Benchmarking , Árboles de Decisión , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Psicológicas , Resultado del Tratamiento , Estados UnidosRESUMEN
Genomic research is an expanding and subversive field, leaking into various others, from environmental protection to food production to healthcare delivery, and in doing so, it is reshaping our relationship with them. The international community has issued various declaratory instruments aimed at the human genome and genomic research. These soft law instruments stress the special nature of genomics and our genetic heritage, and attempt to set limits on our activities with respect to same, as informed by the human rights paradigm. This paper examines the primary thrust and, more importantly, the joint value position of the Universal Declaration on the Human Genome and Human Rights and the Universal Declaration on Bioethics and Human Rights, concluding that, though important legal instruments from the human rights paradigm, these instruments, or rather the values contained therein, must find a more influential hard law voice and a broader policy environment.
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Bioética , Códigos de Ética , Genoma Humano , Derechos Humanos , Principios Morales , Naciones Unidas/ética , Humanos , Cooperación InternacionalRESUMEN
AIM: To describe the autofluorescence features of choroidal melanoma. DESIGN: Non-comparative case series. PARTICIPANTS: 51 consecutive patients. METHODS: Standard fundus photography and autofluorescence photography (580 nm excitation, 695 nm barrier filter) were performed on all patients. Clinical features were correlated with autofluorescence features. MAIN OUTCOME MEASURE: Autofluorescence features of choroidal melanoma and overlying retinal pigment epithelium (RPE). RESULTS: The mean patient age was 59 years. The choroidal melanoma was a mean of 3.6 mm from the optic disc and 2.6 mm from the foveola. The mean tumour basal dimension was 11 mm and the mean tumour thickness was 4 mm. The choroidal melanoma showed intrinsic hypoautofluorescence (39%), isoautofluorescence (6%) and hyperautofluorescence (55%). Slightly increased hyperautofluorescence of the melanoma was found in pigmented tumours (versus non-pigmented), those with greater thickness and basal dimensions, and those with overlying disrupted RPE. Related RPE hyperplasia and atrophy showed hypoautofluorescence, drusen, RPE detachment and subretinal fluid showed slight hyperautofluorescence, and orange pigment displayed the brightest hyperautofluorescence. CONCLUSIONS: Choroidal melanoma generally shows slight intrinsic hyperautofluorescence and the brightness increases with pigmented tumours, larger tumours, and those associated with disrupted RPE. Overlying orange pigment shows remarkably bright hyperautofluorescence.
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Neoplasias de la Coroides/diagnóstico , Melanoma/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fluorescencia , Fondo de Ojo , Humanos , Masculino , Persona de Mediana Edad , Oftalmoscopía/métodos , Epitelio Pigmentado Ocular/patologíaRESUMEN
Two conventional onsite sewage treatment and disposal systems (OSTDSs) at Manatee Springs State Park, Florida, USA, were studied to assess their impact on groundwater quality in a shallow karst environment. Sulfur hexafluoride (SF6) and fluorescein were used as tracers to establish connections between the drainfields and monitoring wells. Elevated nutrients were found in all wells where significant concentrations of both tracers were observed, with the mean of the highest nitrate (NO3) concentration observed at each well being 47.8+/-14.9 (n=11) mg/L NO3-N. The most elevated nutrient concentrations were found directly in the flow path of the effluent. Fecal coliform densities above 10 colony-forming units (cfu)/100 mL were observed in wells with the most rapid connection to the drainfield. The proximity and connectivity of the 0.4-4m thick sandy surficial soils and the underlying karst aquifer allow rapid contaminant transport and limit the ability of conventional OSTDSs to attenuate NO3.