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1.
Hydrol Process ; 36(12): e14785, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37082526

RESUMEN

Channel banks can contribute a significant proportion of fine-grained (<63 µm) sediment to rivers, thereby also contributing to riverine total particulate phosphorus loads. Improving water quality through better agricultural practices alone can be difficult since the contributions from non-agricultural sources, including channel banks, can generate a 'spatial mismatch' between the efficacy of best management applied on farms and the likelihood of meeting environmental objectives. Our study undertook a reconnaissance survey (n = 76 sites each with 3 profiles sampled) to determine the total phosphorus (TP) concentrations of channel banks across England and to determine if TP content can be predicted using readily accessible secondary data. TP concentrations in adjacent field topsoils, local soil soil type/texture and geological parent material were examined as potential predictors of bank TP. Carbon and nitrogen content were also analysed to explore the impacts of organic matter content on measured TP concentrations. The results suggest that channel bank TP concentrations are primarily controlled by parent material rather than P additions to adjacent topsoils through fertilizer and organic matter inputs, but significant local variability in concentrations prevents the prediction of bank TP content using mapped soil type or geology. A median TP concentration of 873 mg kg-1 was calculated for the middle section of the sampled channel bank profiles, with a 25th percentile of 675 mg kg-1, and 75th percentile of 1159 mg kg-1. Using these concentrations and, in comparison with previously published estimates, the estimated number of inland WFD waterbodies in England for which channel bank erosion contributes >20% of the riverine total PP load increased from 15 to 25 (corresponding range of 17-35 using the 25th and 75th percentiles of measured TP concentrations). Collectively, these 25 waterbodies account for 0.2% of the total inland WFD waterbody area comprising England.

2.
Emerg Radiol ; 24(6): 645-651, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28744692

RESUMEN

PURPOSE: We attempted to determine the frequency of acute longus colli tendinitis on diagnostic CT imaging performed at a large multicenter health care system. By correlating with the pre-imaging clinical information, we investigated which patient presentations should lead the radiologist to increased suspicion for this condition. METHODS: Images from a total of 8101 adult CT examinations of the neck and cervical spine performed over a 3-month period were evaluated by researchers independent of the original clinical report. Clinical information available at the time of imaging was reviewed and assigned to one of five categories. Frequency of the condition was calculated by sex and clinical presentation. This retrospective study with waiver of consent and waiver of HIPPA was approved by our IRB. RESULTS: Nine positive scans were found for an overall frequency of 1.1 per 1000 examinations. The frequency was significantly higher (11.4 per thousand) on scans performed of patients presenting without history of recent trauma, concern for tumor, suspected postoperative complication, or clinical signs of infection localized to the neck. Although frequency in males was higher than in females, this did not reach statistical significance. In no positive or negative case was longus colli tendinitis considered in the pre-imaging documentation. CONCLUSIONS: Findings of acute longus colli tendinitis on CT examination generally occur in the absence of prior mention of this condition in the medical record. The radiologist should be particularly alert for this diagnosis when a patient presents with rapid-onset neck pain without a clear history of recent trauma or other etiologies.


Asunto(s)
Músculos del Cuello/diagnóstico por imagen , Dolor de Cuello/diagnóstico por imagen , Tendinopatía/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Enfermedad Aguda , Adolescente , Adulto , Calcinosis/diagnóstico por imagen , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
3.
J Am Geriatr Soc ; 62(11): 2047-55, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25367206

RESUMEN

OBJECTIVES: To examine the relationship between serum biomarkers and self-reported pain intensity and pain-related function, in addition to the contribution of magnetic resonance imaging (MRI) findings of lumbar spine degenerative changes, in older adults with chronic low back pain. DESIGN: Single-center cross-sectional cohort study. SETTING: Academic medical center. PARTICIPANTS: Individuals aged 60 and older with axial low back pain without radiculopathy or previously diagnosed osteoarthritis of the knee or hip or pain outside the low back that is more severe than the back pain (n = 43). MEASUREMENTS: To examine pain-related impairment, pain was measured on a pain thermometer and the McGill Pain Questionnaire Short Form was administered. To examine pain-related function or activity limitation, the Roland Morris Disability Questionnaire, Short Physical Performance Battery (SPPB), and repetitive trunk rotation were used. Single plasma samples were obtained before and after physical performance tests and analyzed for inflammatory markers (E-selectin and regulated on activation, normal T cell expressed and secreted (RANTES)), inhibitors of catabolic enzymes (tissue inhibitor of metalloproteinases-1 (TIMP-1)), markers of matrix turnover (C- telopeptide of type II collagen (CTX-II) and aggrecan chondroitin sulfate 846 (CS846)), and stress biomarkers (neuropeptide Y (NPY)). Conventional nongadolinium lumbar MRI was performed and analyzed quantitatively and clinically. RESULTS: Composite MRI measurements did not show significant correlation with pain or pain-related function. Basal levels and changes in serum biomarkers in response to activity, particularly NPY and RANTES, demonstrated associations with pain and pain-related function in addition to the explanatory power of MRI-based results. CONCLUSION: Serum biomarkers may be a metric for assessment of active disease in older adults, in whom imaging changes are ubiquitous. In addition, changing levels of biomarkers in response to activity suggests that they may be useful as metrics to measure treatment responses in future studies and may reflect potential targets for use in designing personalized treatment for older adults with low back pain.


Asunto(s)
Actividades Cotidianas/clasificación , Biomarcadores/sangre , Mediadores de Inflamación/sangre , Dolor de la Región Lumbar/sangre , Osteoartritis de la Columna Vertebral/sangre , Dimensión del Dolor/estadística & datos numéricos , Anciano , Quimiocina CCL5/sangre , Estudios Transversales , Femenino , Humanos , Vértebras Lumbares/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuropéptido Y/sangre , Osteoartritis de la Columna Vertebral/diagnóstico , Pennsylvania , Proyectos Piloto , Estadística como Asunto
4.
Spine (Phila Pa 1976) ; 39(6): 469-75, 2014 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-24384652

RESUMEN

STUDY DESIGN: Cross sectional study. OBJECTIVE: The goal of this study is to identify relationships between objectively measured and subjectively scored parameters and reported pain. SUMMARY OF BACKGROUND DATA: Studies have demonstrated the unreliability of magnetic resonance imaging (MRI)-based parameters to identify pathological pain generators of chronic low back pain, but they were based on visual inspection and subjective assessment of lumbar disc features. Advancements in computer image analysis provide objective measurements of lumbar disc features. METHODS: Two radiologists evaluated 39 axial and sagittal T1- and T2-weighted MR images of patients with chronic axial low back pain (age, >65 yr) and graded 4 subjective lumbar disc parameters (T2 signal intensity, nucleus shape, Modic changes, and osteophyte formation) whose sum is the cumulative MRI score. Objective parameter, MRI index, was calculated as the product of the measured lumbar disc area and total disc MRI signal intensity. Discs were sorted from least to the most degenerated relative to each parameter. Pearson correlation coefficient and multiple linear regression analysis were performed between the reported pain score and each parameter. RESULTS: The most and least degenerated discs in each patient, as assessed by MRI index, had the highest negative and positive correlation coefficient and regression weight contribution, respectively. All subjective parameters had low correlation coefficients and regression goodness of fit. CONCLUSION: Although limited by small sample size, the objective parameter, MRI index, can be a potential imaging biomarker used to identify possible pain generators. This study presents a potential new application of MR imaging in identifying pain generators of patients with chronic low back pain.


Asunto(s)
Dolor Crónico/diagnóstico , Degeneración del Disco Intervertebral/diagnóstico , Disco Intervertebral/patología , Dolor de la Región Lumbar/diagnóstico , Vértebras Lumbares/patología , Imagen por Resonancia Magnética , Dimensión del Dolor , Percepción del Dolor , Factores de Edad , Anciano , Anciano de 80 o más Años , Dolor Crónico/etiología , Dolor Crónico/patología , Dolor Crónico/psicología , Estudios Transversales , Femenino , Humanos , Degeneración del Disco Intervertebral/complicaciones , Degeneración del Disco Intervertebral/patología , Degeneración del Disco Intervertebral/psicología , Modelos Lineales , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/patología , Dolor de la Región Lumbar/psicología , Masculino , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad
5.
Neurobiol Aging ; 33(4): 834.e7-16, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21943959

RESUMEN

Cerebral white matter lesions (WMLs) reflect small vessel disease, are common in elderly individuals, and are associated with cognitive impairment. We sought to determine the relationships between WMLs, age, gray matter (GM) volume, and cognition in the Cardiovascular Health Study (CHS). From the Cardiovascular Health Study we selected 740 cognitively normal controls with a 1.5 T magnetic resonance imaging (MRI) scan of the brain and a detailed diagnostic evaluation. WML severity was determined using a standardized visual rating system. GM volumes were analyzed using voxel-based morphometry implemented in the Statistical Parametric Mapping software. WMLs were inversely correlated with GM volume, with the greatest volume loss in the frontal cortex. Age-related atrophy was observed in the hippocampus and posterior cingulate cortex. Regression analyses revealed links among age, APOE*4 allele, hypertension, WMLs, GM volume, and digit symbol substitution test scores. Both advancing age and hypertension predict higher WML load, which is itself associated with GM atrophy. Longitudinal data are needed to confirm the temporal sequence of events leading to a decline in cognitive function.


Asunto(s)
Envejecimiento/patología , Encéfalo/patología , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/patología , Leucoaraiosis/complicaciones , Leucoaraiosis/patología , Anciano , Anciano de 80 o más Años , Envejecimiento/genética , Apolipoproteína E4/genética , Femenino , Humanos , Imagenología Tridimensional , Leucoaraiosis/genética , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Trastornos de la Memoria/etiología , Trastornos de la Memoria/patología , Escala del Estado Mental , Pruebas Neuropsicológicas , Análisis de Regresión , Estudios Retrospectivos
6.
J Comput Assist Tomogr ; 33(6): 917-22, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19940660

RESUMEN

BACKGROUND AND PURPOSE: Influenza A infection can precipitate encephalopathy, encephalitis, or Reye syndrome with the development of cerebral edema in children and is associated with an increased incidence of stroke in adults. The mechanism of these events is poorly understood. Posterior reversible encephalopathy syndrome (PRES) is seen in association with infection/sepsis, and cerebral vasculopathy has been demonstrated in PRES. We describe a case of PRES that develops in association with influenza A. SUMMARY OF CASE: A normotensive 65-year-old woman presented with altered mentation and nausea in the setting of a viral prodromal illness ultimately confirmed as influenza A. Posterior reversible encephalopathy syndrome developed on the second day after admission. Catheter cerebral angiogram documented vasculopathy in PRES-involved regions with areas of focal vessel dilatation and string-of-bead appearance. CONCLUSIONS: The association between influenza A and PRES with documentation of cerebral vasculopathy suggests a common systemic vascular mechanism behind PRES and influenza-related encephalopathic edema and stroke.


Asunto(s)
Trastornos Cerebrovasculares/etiología , Encefalopatía Hipertensiva/etiología , Virus de la Influenza A/aislamiento & purificación , Gripe Humana/complicaciones , Anciano , Angiografía Cerebral , Trastornos Cerebrovasculares/diagnóstico , Femenino , Humanos , Encefalopatía Hipertensiva/diagnóstico , Gripe Humana/diagnóstico , Imagen por Resonancia Magnética , Síndrome , Tomografía Computarizada por Rayos X
7.
J Environ Manage ; 90(8): 2578-88, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19249151

RESUMEN

Soil erosion on agricultural land is a growing problem in Western Europe and constitutes a threat to soil quality and to the ability of soils to provide environmental services. The off-site impacts of runoff and eroded soil, principally eutrophication of water bodies, sedimentation of gravel-bedded rivers, loss of reservoir capacity, muddy flooding of roads and communities, are increasingly recognised and costed. The shift of funding in the European Union (EU) from production-related to avoidance of pollution and landscape protection, raises issues of cross-compliance: public support for agriculture has to be seen to give value-for-money. In this context risk-assessment procedures have been introduced to help farmers recognise sites where either certain crops should not be grown or anti-erosion measures are required. In England, Defra [Defra, 2005a. Controlling Soil Erosion: a Manual for the Assessment and Management of Agricultural Land at Risk of Water Erosion in Lowland England. Revised September 2005. Department for Environment, Food and Rural Affairs, London] sets out a system of risk-assessment, including ranking of crops susceptible to erosion and anti-erosion measures, that may be selected. We assess this system using field data for an area of erodible soils in the Rother valley, Sussex. The Defra approach correctly identifies most at-risk fields and, taken together with land-use maps, allows non-compliance with advice to be highlighted. We suggest a simple extension to the system which would further identify at-risk fields in terms of possible damage to roads and rivers from muddy runoff. The increased risk of erosion in the study area is associated with certain crops: potatoes, winter cereals, maize and grazed turnips and seems unlikely to be the result of changes in rainfall which over the last 130 years are minimal. We have not evaluated proposed anti-erosion measures in the area because few have been put into practice. The European Water Framework Directive will increasingly focus attention on agricultural fields as a source of river pollution. Assessing the risk of erosion and the need for field testing of suggested approaches, are not simply issues for the EU, but for the management of global agricultural systems.


Asunto(s)
Agricultura , Monitoreo del Ambiente/métodos , Medición de Riesgo/métodos , Suelo/análisis , Conservación de los Recursos Naturales , Reino Unido
8.
Otolaryngol Clin North Am ; 41(1): 195-213, vii, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18261532

RESUMEN

Endoscopic surgery using an expanded endonasal approach now allows surgical access to an increasing range of parasellar, suprasellar, clivus, and petrous apex lesions. Accurate preoperative planning requires proper interpretation of CT and MRI results. It is essential to identify important anatomic landmarks and to recognize the appearance of common lesions and pseudolesions. Postoperative imaging must evaluate for residual tumors and identify iatrogenic conditions.


Asunto(s)
Enfermedades Óseas/diagnóstico , Seno Cavernoso/patología , Trastornos Cerebrovasculares/diagnóstico , Hueso Petroso/patología , Aneurisma/diagnóstico , Encefalopatías/diagnóstico , Seno Cavernoso/inervación , Humanos , Imagen por Resonancia Magnética/métodos , Meningioma/diagnóstico , Hueso Petroso/irrigación sanguínea , Neoplasias Hipofisarias/diagnóstico , Base del Cráneo/patología , Neoplasias Craneales/diagnóstico , Tomografía Computarizada por Rayos X/métodos
9.
J Comput Assist Tomogr ; 31(1): 148-56, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17259848

RESUMEN

In a retrospective review, 3 (3.8%) of 78 patients developed recurrent posterior reversible encephalopathy syndrome. Underlying clinical conditions included sickle cell disease, antibody-positive autoimmune disease, and allogeneic bone marrow transplantation. Infection (bacterial/viral) was suspected or documented in both episodes in all 3 patients. Evidence of endothelial injury (schistocyte formation and increased lactate dehydrogenase) was documented in all patients, and multiple organ dysfunction syndrome developed during the hospital course of all admissions.


Asunto(s)
Edema Encefálico/diagnóstico , Insuficiencia Multiorgánica/diagnóstico , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Síndrome , Tomografía Computarizada por Rayos X
10.
Neuroradiology ; 48(7): 449-59, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16699802

RESUMEN

INTRODUCTION: The purpose of this study was to compare the differences in gland enhancement, microlesion enhancement and gland-lesion contrast ratio in patient groups in which half-dose (HD), standard-dose (SD) and double-dose (DD) contrast medium was used in pituitary MR imaging. METHODS: Pituitary gland enhancement and microlesion enhancement were measured and gland-lesion contrast ratios were calculated in 18 patients receiving HD (0.05 mmol/kg), 9 receiving SD (0.1 mmol/kg) and 13 receiving DD (0.2 mmol/kg) contrast medium. Gland enhancement and microlesion enhancement over baseline were determined employing DICOM region of interest measurements and compared after normalization to temporal lobe white matter. Contrast ratios and differences were also calculated and compared. RESULTS: Gland enhancement and lesion enhancement were greater with larger contrast medium doses (gland: HD 50%, SD 99%, DD 132%; microlesion: HD 19%, SD 54%, DD 86%). The gland-lesion contrast ratios were similar with the three doses (25.6%), reflecting expected similar fractional contrast medium distributions in spite of different doses. The signal difference between gland and microlesion, therefore, was a fixed percentage of gland enhancement (DeltaS approximately 26%) with greater signal differences with larger contrast medium doses. CONCLUSION: Greater gland-to-lesion signal differences with larger contrast medium doses would likely improve pituitary microlesion visualization and margin characterization aiding in microlesion detection as well as preoperative planning.


Asunto(s)
Medios de Contraste/administración & dosificación , Gadolinio DTPA/administración & dosificación , Compuestos Heterocíclicos/administración & dosificación , Imagen por Resonancia Magnética , Compuestos Organometálicos/administración & dosificación , Enfermedades de la Hipófisis/patología , Hipófisis/patología , Adolescente , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Gadolinio , Humanos , Aumento de la Imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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