Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
1.
Water Res ; 163: 114851, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31323501

RESUMEN

Oil-contaminated wastewaters are generally treated by a combination of physico-chemical and biological methods. Interest in the anaerobic treatment of oily wastewaters has increased since it complements aerobic treatment and produces energy in the form of methane. The objectives of this study were to characterise the anaerobic process spontaneously occurring in a full-scale storage tank at a facility treating waste oil and oil-contaminated effluents, and to evaluate the applicability of an anaerobic moving bed biofilm reactor (AnMBBR) and an anaerobic contact reactor (ACR) for treating the oil contaminated wastewater feeding the storage tank. Three lab-scale reactors were operated in parallel over 465 days: one mesophilic and one thermophilic AnMBBR, and one thermophilic ACR. The wastewater had a high strength with an average chemical oxygen demand (COD) of 36 g/L with a soluble fraction of 80%. The BOD7/COD ratios varied between 0.1 and 0.5, indicating low aerobic degradability. However, biomethane potential tests indicated some level of anaerobic degradability with methane yields between 150 and 200 NmL/gCOD. The full-scale storage tank operated at low organic loading rates (0.35-0.43 kgCOD/m3d), and long hydraulic retention times (HRT = 83-104 d). In comparison, the AnMBBRs achieved similar COD reductions (60%) as the full-scale tank but at a much shorter HRT of 30 d. Similar efficiency could only be reached at longer HRTs (43 d) in the ACR due to low biomass levels resulting from poor sludge settleability. The methane yield was higher (210 NmLCH4/COD removed) in the AnMBBR operated at 37 °C, compared to the other reactors working at 50 °C (180 NmLCH4/COD removed). This reactor also maintained a higher COD removal (67%) at an increased OLR of 1.1 kgCOD/m3d than the AnMBBR at 50 °C. The microbial composition of the biomass from the full-scale tank and the laboratory reactors provided evidence for the conversion of oil-contaminated wastewater into methane with a relatively high abundance of hydrogenotrophic methanogens.


Asunto(s)
Eliminación de Residuos Líquidos , Aguas Residuales , Anaerobiosis , Biopelículas , Reactores Biológicos , Metano
2.
Osteoporos Int ; 30(10): 1961-1971, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31227884

RESUMEN

In a population-based study of older Swedish women, we investigated if clinical vertebral fracture was associated with lower health-related quality of life (HRQoL) and determined whether the association remained over time. Clinical vertebral fracture was associated with lower HRQoL and the effect persisted for up to 18.9 years. INTRODUCTION: Vertebral fractures are often associated with back pain and reduced physical function, which might result in isolation and depression. As a result, women with vertebral fractures often have lower health-related quality of life (HRQoL), but during what time frame the decrease lingers is unclear. Therefore, the aim of this study was to investigate if clinical vertebral fracture and hip fracture were associated with lower HRQoL and to determine whether the associations remained over time. METHODS: Vertebral fracture assessments (VFA) were performed using dual-energy X-ray absorptiometry. Data regarding prior fractures, medications, medical history, and physical activity was collected using a questionnaire. Self-rated physical HRQoL was assessed using the 12-Item Short-Form Health Survey (SF-12). Women with clinical vertebral fractures were divided into tertiles according to time since fracture onset and their HRQoL was compared with non-fractured women. RESULTS: In a population-based cross-sectional study of 3028 women aged 77.8 ± 1.63 (mean ± SD), a total of 130 (4.3%) women reported at least one clinical vertebral fracture. Women with a clinical vertebral fracture, divided into tertiles (T1-T3) depending on time since the fracture occurred, had lower HRQoL (T1: 36.3 ± 10.8; T2: 41.0 ± 9.94; and T3:41.6 ± 11.4) than women without fracture (46.2 ± 10.6; p < 0.001). Using linear regression analysis, clinical vertebral fracture was associated with reduced physical HRQoL for up to 18.9 years, independently of covariates (age, height, weight, smoking, prior stroke, mental HRQoL, grip strength, and lumbar spine BMD). CONCLUSIONS: Clinical vertebral fracture was associated with lower self-rated physical HRQoL, for up to 18.9 years after time of fracture.


Asunto(s)
Fracturas Osteoporóticas/rehabilitación , Calidad de Vida , Fracturas de la Columna Vertebral/rehabilitación , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Antropometría/métodos , Densidad Ósea/fisiología , Estudios Transversales , Ejercicio Físico/fisiología , Femenino , Fracturas de Cadera/epidemiología , Fracturas de Cadera/fisiopatología , Fracturas de Cadera/rehabilitación , Humanos , Vértebras Lumbares/fisiopatología , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/fisiopatología , Aptitud Física/fisiología , Psicometría , Sistema de Registros , Autoinforme , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/fisiopatología , Suecia/epidemiología , Factores de Tiempo
3.
Osteoporos Int ; 28(9): 2521-2540, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28585054

RESUMEN

Vertebral compression fracture (VCF) is a common fragility fracture and the starting point of a lasting, painful, disabling condition. The aim was to summarize evidence of person-centered/non-medical interventions supporting women with VCF. Results show small numbers of studies with only probable effect on function, pain, QoL, fear of falling, and psychological symptoms. The vertebral compression fracture (VCF) caused by osteoporosis is the third most common fragility fracture worldwide. Previously, it was believed that the pain caused by VCF was self-subsiding within weeks or a few months post-fracture. However, this positive prognosis has been refuted by studies showing that, for the great majority of patients, the VCF was the starting point of a long-lasting, severely painful, and disabling condition. The low number of studies focusing on the experience of the natural course of VCF, and what support is available and how it is perceived by those affected, calls for further investigation. Strengthening older patients' sense of security and increasing confidence in their own abilities are of great importance for successful rehabilitation following VCF. More research is needed to identify resources, possibilities, and strategies that can assist older patients to reach their goals to improve well-being. The purpose of this systematic review was to identify and summarize the current evidence of person-centered or other structured non-medical/non-surgical interventions supporting older women after experiencing an osteoporotic VCF. A systematic literature search was conducted on the MeSH terms encompassing osteoporosis and vertebral compression fractures in the PubMed-MEDLINE and Cumulative Index for Nursing and Allied Health Literature (CINAHL) databases during March through June 2015. The initial search identified 8789 articles, but only seven articles (six randomized controlled trials and one observational study with a control group) met the inclusion criteria. It became evident from the current study that the availability of evidence on the effects of non-medical interventions aiming to support older women with VCF is limited, to say the least. The trials included in this review have few limitations and were mainly considered to be of moderate quality. This systematic literature review suggests that non-medical interventions aiming to support older women with VCF might decrease levels of pain and use of analgesic as well as promote improved physical mobility and function. These interventions would probably result in an improved difference in experiences of fear of falling and perceived psychological symptoms, but would only slightly improve quality of life. However, given the nature of the seven studies, potential biases in patient selection, issues around precision with small cohorts, and failure to control for confounders, makes it difficult to draw a definitive conclusion about the significant effects of non-medical interventions. Incurring a VCF is a complex and diverse event, necessitating equally complex interventions to identify new ways forward. However, to date, interventions struggle with a risk of selection bias in that only the needs of the healthiest of the population are addressed and the voices of the remaining majority of the people affected by VCF are unheard.


Asunto(s)
Fracturas por Compresión/terapia , Fracturas Osteoporóticas/terapia , Atención Dirigida al Paciente/métodos , Fracturas de la Columna Vertebral/terapia , Dolor de Espalda/etiología , Dolor de Espalda/terapia , Medicina Basada en la Evidencia/métodos , Femenino , Fracturas por Compresión/complicaciones , Fracturas por Compresión/psicología , Humanos , Fracturas Osteoporóticas/complicaciones , Fracturas Osteoporóticas/psicología , Calidad de Vida , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/psicología
4.
Phys Med Biol ; 62(8): 2976-2989, 2017 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-28306555

RESUMEN

Dosimetric errors in a magnetic resonance imaging (MRI) only radiotherapy workflow may be caused by system specific geometric distortion from MRI. The aim of this study was to evaluate the impact on planned dose distribution and delineated structures for prostate patients, originating from this distortion. A method was developed, in which computer tomography (CT) images were distorted using the MRI distortion field. The displacement map for an optimized MRI treatment planning sequence was measured using a dedicated phantom in a 3 T MRI system. To simulate the distortion aspects of a synthetic CT (electron density derived from MR images), the displacement map was applied to CT images, referred to as distorted CT images. A volumetric modulated arc prostate treatment plan was applied to the original CT and the distorted CT, creating a reference and a distorted CT dose distribution. By applying the inverse of the displacement map to the distorted CT dose distribution, a dose distribution in the same geometry as the original CT images was created. For 10 prostate cancer patients, the dose difference between the reference dose distribution and inverse distorted CT dose distribution was analyzed in isodose level bins. The mean magnitude of the geometric distortion was 1.97 mm for the radial distance of 200-250 mm from isocenter. The mean percentage dose differences for all isodose level bins, were ⩽0.02% and the radiotherapy structure mean volume deviations were <0.2%. The method developed can quantify the dosimetric effects of MRI system specific distortion in a prostate MRI only radiotherapy workflow, separated from dosimetric effects originating from synthetic CT generation. No clinically relevant dose difference or structure deformation was found when 3D distortion correction and high acquisition bandwidth was used. The method could be used for any MRI sequence together with any anatomy of interest.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen , Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Anciano , Humanos , Masculino , Neoplasias de la Próstata/patología , Radioterapia Conformacional/métodos , Tomografía Computarizada por Rayos X/métodos , Flujo de Trabajo
5.
Osteoporos Int ; 27(5): 1729-36, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26659067

RESUMEN

UNLABELLED: Vertebral compression fractures (VCF) cause pain and decreased physical ability, with no known well-established treatment. The aim of this study was to illuminate the experience of living with a VCF. The results show that fear and concerns are a major part of daily life. The women's initial contact with health-care providers should focus on making them feel acknowledged by offering person-centered and tailored support. INTRODUCTION: In the past decade, osteoporotic-related fractures have become an increasingly common and costly public health problem worldwide. Vertebral compression fracture (VCF) is the second most common osteoporotic fracture, and patients with VCF describe an abrupt descent into disability, with a subsequent desire to regain independence in everyday life; however, little is known of their situation. The aim of this study was to illuminate the lived experience of women with an osteoporotic VCF. METHODS: Ten women were interviewed during 2012-2013, starting with an open-ended question: could you tell me what it is like to live with a vertebral compression fracture? The verbatim transcribed interviews were analyzed using a phenomenological hermeneutical approach. RESULTS: The narrative provided descriptions of living in turmoil and chaos, unable to find stability in their life with little improvement regarding pain and physical function. Shifts from periods of constant pain to periods of fear of constant pain created a loss of confidence and an increased sense of confinement. The structural analysis revealed fear and concerns as the most prominent experience building on five themes: struggling to understand a deceiving body, breakthrough pain fueling fear, fearing a trajectory into isolation, concerns of dependency, and fearing an uncertain future. CONCLUSIONS: Until researchers find a successful prevention or medical/surgical treatment for osteoporotic VCFs, health-care providers and society abandon these women to remain in a painful and never ending story.


Asunto(s)
Actitud Frente a la Salud , Fracturas por Compresión/psicología , Fracturas Osteoporóticas/psicología , Fracturas de la Columna Vertebral/psicología , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Dolor Crónico/etiología , Miedo , Femenino , Fracturas por Compresión/complicaciones , Fracturas por Compresión/rehabilitación , Conocimientos, Actitudes y Práctica en Salud , Humanos , Entrevistas como Asunto , Fracturas Osteoporóticas/complicaciones , Fracturas Osteoporóticas/rehabilitación , Aislamiento Social , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/rehabilitación , Suecia
7.
Magn Reson Med ; 71(6): 2180-5, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23878094

RESUMEN

PURPOSE: A segmented inversion-recovery module combined with the 2D ultrashort echo time radial technique is proposed that allows accurate pixel level T(1) mapping of mouse lung in vivo. METHODS: Numerical simulations were performed to estimate T(1) measurement accuracy and precision versus flip angle and signal-to-noise ratio. Phantom measurements were used for protocol validation, where the segmented inversion-recovery ultrashort echo-time sequence was compared with the reference technique (inversion-recovery rapid acquisition with refocused echoes). The in vivo experiments were carried out on free-breathing C57 mice (n = 10), breathing first air and then oxygen. RESULTS: The simulations demonstrated the high potential of the technique for accurate and precise T(1) assessment. Phantom experiments showed good agreement for T(1) values measured with segmented inversion-recovery ultrashort echo-time and the reference technique. The in vivo experiment demonstrated the utility of the technique in oxygen-enhanced assessment, where small T(1) changes were detected with high precision. CONCLUSION: Segmented inversion-recovery ultrashort echo-time provides accurate, high resolution T(1) mapping of the lung parenchyma.


Asunto(s)
Pulmón/anatomía & histología , Imagen por Resonancia Magnética/métodos , Algoritmos , Animales , Simulación por Computador , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Ratones , Ratones Endogámicos C57BL , Oxígeno/metabolismo , Fantasmas de Imagen
8.
IEEE Trans Biomed Eng ; 59(3): 777-86, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22167560

RESUMEN

Pulmonary diseases are known to be largely inhomogeneous. To evaluate such inhomogeneities, we are testing an image-based method to measure gas flow in the lung regionally. Dynamic, spin-density-weighted hyperpolarized (3)He MR images performed during slow inhalation of this gas were analyzed to quantify regional inflation rate. This parameter was measured in regions of interest (ROIs) that were defined by a rectangular grid that covered the entire rat lung and grew dynamically with it during its inflation. We used regional inflation rate to quantify elastase-induced emphysema and to differentiate healthy (n = 8) from elastase-treated (n = 9) rat lungs as well as healthy from elastase-treated areas of one rat unilaterally treated with elastase in the left lung. Emphysema was also assessed by gold standard morphological and well-established hyperpolarized (3)He MRI diffusion measurements. Mean values of regional inflation rates were significantly different for healthy and elastase-treated animals and correlated well with the apparent diffusion coefficient of (3)He and morphological measurements. The image-based biomarker inflation rate may be useful for the assessment of regional lung ventilation.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Helio , Enfisema Pulmonar/diagnóstico , Animales , Modelos Animales de Enfermedad , Femenino , Isótopos , Elastasa Pancreática , Enfisema Pulmonar/patología , Ratas , Ratas Wistar , Sensibilidad y Especificidad
9.
Water Sci Technol ; 55(6): 89-97, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17486839

RESUMEN

The nutrient limited biofilm-activated sludge (BAS) process was developed with the aim to ensure maximum biological treatment efficiency in combination with good process stability, low sludge production and minimum effluent concentration of nutrients. The first full scale nutrient limited BAS (NLBAS) processes were implemented at Södra Cell Värö and Stora Enso Hylte in 2002. Since then another three full scale installations have been built. The aim of this study was to investigate and summarise the long-term treatment results, process stability, sludge production and sludge characteristics for the five full scale NLBAS processes. It was of particular interest to compare the nutrient limited operating mode with regard to the different types of production and wastewater that the mills represent (kraft, TMP and newsprint, bleached CTMP). The study showed that after the initial start-up period, which varied from a couple of weeks to three to four months, all plants meet their respective discharge limits. The sludge production for the different plants varies between 0.07 and 0.15 kg TSS/kg COD and the sludge characteristics are with few exceptions excellent. In conclusion, the nutrient limited BAS process is suitable for both upgrades and new installations of biological treatment for different types of forest industry wastewaters.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Residuos Industriales , Aguas del Alcantarillado/química , Árboles , Eliminación de Residuos Líquidos/métodos , Factores de Tiempo
10.
Magn Reson Med ; 52(5): 1043-51, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15508152

RESUMEN

A new technique for assessing tissue blood flow using hyperpolarized tracers, based on the fact that the magnetization of a hyperpolarized substance can be destroyed permanently, is described. Assessments of blood flow with this technique are inherently insensitive to arterial delay and dispersion, and allow for quantification of the transit time and dispersion in the arteries that supply the investigated tissue. Renal cortical blood flow was studied in six rabbits using a 13C-labeled compound (2-hydroxyethylacrylate) that was polarized by the parahydrogen-induced polarization (PHIP) technique. The renal cortical blood flow was estimated to be 5.7/5.4 +/- 1.6/1.3 ml/min per milliliter of tissue (mean +/- SD, right/left kidney), and the mean transit time and dispersion in the renal arteries were determined to be 1.47/1.42 +/- 0.07/0.07 s and 1.78/1.93 +/- 0.40/0.42 s2, respectively.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Circulación Renal/fisiología , Algoritmos , Animales , Artefactos , Volumen Sanguíneo/fisiología , Isótopos de Carbono , Procesamiento de Imagen Asistido por Computador , Masculino , Conejos , Estadísticas no Paramétricas
11.
J Appl Clin Med Phys ; 4(4): 352-64, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14604425

RESUMEN

The purpose of this research was to investigate the geometrical accuracy of magnetic resonance (MR) images used in the radiation therapy treatment planning for lung cancer. In this study, the capability of MR imaging to acquire dynamic two-dimensional images was explored to access the motion of lung tumors. Due to a number of factors, including the use of a large field-of-view for the thorax, MR images are particularly subject to geometrical distortions caused by the inhomogeneity and gradient nonlinearity of the magnetic field. To quantify such distortions, we constructed a phantom, which approximated the dimensions of the upper thorax and included two air cavities. Evenly spaced vials containing contrast agent could be held in three directions with their cross-sections in the coronal, sagittal, and axial planes, respectively, within the air cavities. MR images of the phantom were acquired using fast spin echo (FSE) and fast gradient echo (fGRE) sequences. The positions of the vials according to their centers of mass were measured from the MR images and registered to the corresponding computed tomography images for comparison. Results showed the fGRE sequence exhibited no errors >2.0 mm in the sagittal and coronal planes, whereas the FSE sequence produced images with errors between 2.0 and 4.0 mm along the phantom's perimeter in the axial plane. On the basis of these results, the fGRE sequence was considered to be clinically acceptable in acquiring images in all sagittal and coronal planes tested. However, the spatial accuracy in periphery of the axial FSE images exceeded the acceptable criteria for the acquisition parameters used in this study.


Asunto(s)
Neoplasias Pulmonares/radioterapia , Imagen por Resonancia Magnética/normas , Simulación por Computador , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Interpretación de Imagen Asistida por Computador/normas , Neoplasias Pulmonares/patología , Modelos Teóricos , Fantasmas de Imagen/normas , Garantía de la Calidad de Atención de Salud/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Planificación de la Radioterapia Asistida por Computador/normas , Radioterapia Asistida por Computador/métodos , Radioterapia Asistida por Computador/normas
12.
Br J Radiol ; 76 Spec No 2: S118-27, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15572334

RESUMEN

MRI provides unsurpassed soft tissue contrast, but the inherent low sensitivity of this modality has limited the clinical use to imaging of water protons. With hyperpolarization techniques, the signal from a given number of nuclear spins can be raised more than 100 000 times. The strong signal enhancement enables imaging of nuclei other than protons, e.g. (13)C and (15)N, and their molecular distribution in vivo can be visualized in a clinically relevant time window. This article reviews different hyperpolarization techniques and some of the many application areas. As an example, experiments are presented where hyperpolarized (13)C nuclei have been injected into rabbits, followed by rapid (13)C MRI with high spatial resolution (scan time <1 s and 1.0 mm in-plane resolution). The high degree of polarization thus enabled mapping of the molecular distribution within various organs, a few seconds after injection. The hyperpolarized (13)C MRI technique allows a selective identification of the molecules that give rise to the MR signal, offering direct molecular imaging.


Asunto(s)
Isótopos de Carbono , Imagen por Resonancia Magnética/métodos , Animales , Isótopos de Carbono/análisis , Humanos , Enfermedades Pulmonares/diagnóstico , Masculino , Modelos Químicos , Conejos , Termodinámica
13.
J Magn Reson ; 159(1): 68-75, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12468305

RESUMEN

The influence of flip angle and flow velocity on the signal intensity achieved when imaging a hyperpolarized substance with a spoiled gradient echo sequence was investigated. The study was performed both theoretically and experimentally using hyperpolarized xenon dissolved in ethanol. Analytical expressions regarding the optimal flip angle with respect to signal and the corresponding signal level are presented and comparisons with thermally polarized substances are made. Both experimentally and theoretically, the optimal flip angle was found to increase with increasing flow velocity. Numerical calculations showed that the velocity dependence of the signal differs between the cases of hyperpolarized and thermally polarized substances.


Asunto(s)
Imagen Eco-Planar/métodos , Angiografía por Resonancia Magnética/métodos , Isótopos de Xenón/química , Etanol , Fantasmas de Imagen
14.
Acta Radiol ; 43(5): 455-60, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12423454

RESUMEN

PURPOSE: The feasibility of hyperpolarized 129Xe for fast MR angiography (MRA) was evaluated using the echo-planar imaging (EPI) technique. MATERIAL AND METHODS: Hyperpolarized Xe gas was dissolved in ethanol, a carrier agent with high solubility for Xe (Ostwald solubility coefficient 2.5) and long relaxation times. The dissolved Xe was injected as a bolus into a flow phantom where the mean flow velocity was 15 cm/s. Ultrafast EPI images with 44 ms scan time were acquired of the flowing bolus and the signal-to-noise ratios (SNR) were measured. RESULTS: The relaxation times of hyperpolarized Xe in ethanol were measured to T1=160+/-11 s and T2 approximately 20 s. The resulting images of the flowing liquid were of reasonable quality and had an SNR of about 70. CONCLUSION: Based on the SNR of the obtained Xe EPI images, it was estimated that rapid in vivo MRA with 129Xe may be feasible, provided that an efficient, biologically acceptable carrier for Xe can be found and polarization levels of more than 25% can be achieved in isotopically enriched 129Xe.


Asunto(s)
Imagen Eco-Planar , Angiografía por Resonancia Magnética/métodos , Isótopos de Xenón , Estudios de Factibilidad
15.
Magn Reson Med ; 46(6): 1067-71, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11746570

RESUMEN

The negatively charged contrast agent Gd-DTPA2- distributes inversely to the cartilage fixed charged density. This enables structural cartilage examinations by contrast-enhanced MRI. In line with the development of a clinically applicable protocol for such examinations, this study describes the temporal pattern of Gd-DTPA2- distribution in femoral knee cartilage at three different doses in healthy volunteers. Nineteen volunteers (ages 21-28 years) were examined with a 1.5T MRI system. Quantitative relaxation rate measurements were made in weight-bearing central parts of femoral cartilage using sets of five turbo inversion recovery images with different inversion times. The cartilage was analyzed before and four times (1-4 h) after an intravenous injection of Gd-DTPA2- at single, double, and triple doses: 0.1, 0.2, and 0.3 mmol/kg body weight, respectively. The increase in R1 postcontrast was linearly dose-related at all times. The highest R1 values were registered at 2 and 3 h postcontrast, suggesting 2 h to be optimal in the clinical situation. The triple dose indicated a subtle compartmental difference in men, with higher contrast distribution medially than laterally. Results suggest that the triple dose is needed to detect minor cartilage matrix differences.


Asunto(s)
Cartílago Articular/anatomía & histología , Medios de Contraste/administración & dosificación , Gadolinio DTPA , Articulación de la Rodilla , Imagen por Resonancia Magnética , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Gadolinio DTPA/administración & dosificación , Humanos , Masculino
16.
Urology ; 58(4): 570-2, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11597541

RESUMEN

OBJECTIVES: To perform a prospective study using confidential patient-completed questionnaires about their urinary habits before and after laparoscopic radical prostatectomy. Published reports on urinary continence after radical prostatectomy vary depending on the definitions of urinary continence and methods of data collection. METHODS: From May 1998 to February 2000, 228 men underwent laparoscopic radical prostatectomy for clinically localized prostate cancer. The patients were given questionnaires before surgery and at 1, 3, 6, and 12 months postoperatively. RESULTS: Before surgery, no patient reported incontinence. At 1, 3, 6, and 12 months postoperatively, perfect diurnal urinary control (no pads, no leakage at all) was reported in 9.9%, 28.6%, 57.4%, and 56.8% of patients, respectively. No pads were used in 18.8%, 58.4%, 68.9%, and 78.4% at 1, 3, 6, and 12 months, respectively. No patient reported use of more than 1 pad daily at 6 months of follow-up. CONCLUSIONS: Continence after laparoscopic radical prostatectomy is comparable to the results after traditional radical retropubic prostatectomy. Ongoing use of the laparoscopic route for treating clinically localized prostate cancer is warranted.


Asunto(s)
Laparoscopía/efectos adversos , Prostatectomía/efectos adversos , Incontinencia Urinaria/etiología , Anciano , Anastomosis Quirúrgica , Estudios de Seguimiento , Humanos , Incidencia , Laparoscopía/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Prostatectomía/métodos , Prostatectomía/estadística & datos numéricos , Encuestas y Cuestionarios , Incontinencia Urinaria/clasificación , Incontinencia Urinaria/epidemiología
17.
J Urol ; 166(5): 1662-4, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11586197

RESUMEN

PURPOSE: We prospectively tested the safety of routine removal of the catheter as early as 2 to 4 days after laparoscopic radical prostatectomy. MATERIALS AND METHODS: Between March 1998 and March 2001, 228 patients underwent laparoscopic radical prostatectomy for clinically organ confined prostate cancer. The last 113 consecutive patients were included in a prospective study according to gravitational cystography performed 2 to 4 days postoperatively. If no leak was seen the catheter was removed. If a leak was apparent the catheter was left indwelling for another 6 days and cystography was repeated. RESULTS: Cystography 2 to 4 days postoperatively showed an anastomosis without a leak in 96 (84.9%) patients who subsequently had the catheters removed. There were 28 patients who had the catheter removed on postoperative day 2, 28 day 3 and 40 day 4. In 17 (15.1%) patients an anastomotic leak was observed, and the catheter was not removed at that time. Of the 96 patients in whom the catheter was removed early 10 (10.4%) had urinary retention that necessitated re-catheterization. This procedure was performed without the need for cystoscopy. After the catheter was removed all patients were able to void 24 hours later. Median followup was 7 months (range 1 to 15) and showed continence rates greater than 93%. No anastomotic stricture, pelvic abscess or urinoma developed in any patient. CONCLUSIONS: Patients who undergo laparoscopic radical prostatectomy can have the catheter safely removed 2 to 4 days postoperatively without a higher risk of incontinence, stricture or leak related problems.


Asunto(s)
Laparoscopía , Prostatectomía/métodos , Cateterismo Urinario , Humanos , Masculino , Cuidados Posoperatorios , Estudios Prospectivos , Neoplasias de la Próstata/cirugía , Técnicas de Sutura , Factores de Tiempo
18.
Eur Urol ; 40(1): 38-45, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11528175

RESUMEN

OBJECTIVES: In an effort to reduce the morbidity associated to radical prostatectomy, we implemented laparoscopic surgery to this advanced ablative and reconstructive procedure. In our study, we describe our operative technique and assess our results in terms of oncologic cure, continence and potency. METHODS: 200 patients with clinically localized prostate cancer underwent laparoscopic radical prostatectomy. 66 of these patients were either referred, or operated during surgical demonstrations. Thus, complete evaluation is based on a homogeneous personal series of 134 patients and was performed by an independent clinical analyst. There were 91 T1 and 43 T2. We did not perform pelvic lymph node excision in 78 patients whose PSA was less than 10 ng/ml and the Gleason score of endorectal biopsies was below 7. The surgical procedure recapitulated the steps of traditional retropubic prostatectomy with one basic difference however: the first step of the technique consisted in a rectoprostatic cleavage, which was done transperitoneally. Except for the first 10 patients, the vesicourethral reconstruction was performed either with two hemi-circumferential or a single circumferential running suture. RESULTS: All interventions were performed as planned, no conversions were necessary, and only 4 patients required blood transfusion. Operating time decreased with growing experience; after the first 20 patients the usual operating time was 3.5 h without and 4 h with lymphadenectomy. The surgical complication rate was 22.5% in the first 40 patients, and 3.2% in the remaining 94 patients. Except for the first 10 patients, the mean hospital stay was 6.1 days and bladder catheterization 4.8 days. Median catheterization time was 4 days. Histological study of the specimen showed pT2 disease in 101 patients and pT3 in 33 patients, the rate of positive margins was 16.8 and 48.8%, respectively. At 1 year, overall erection rate (with or without sexual intercourse) was 56%, the rate of patients without pad was 86.2% during the day and 100% during the night. CONCLUSIONS: Laparoscopic environment seems to comply with the oncologic goals of radical prostatectomy. Improved intraoperative visualization and magnification may provide benefits for the preservation of continence and potency by allowing a more precise dissection and vesicourethral reconstruction. Despite longer operative times and the steep learning curve this new technique is currently proliferating due to expectations of decreased postoperative morbidity and better quality of life.


Asunto(s)
Laparoscopía , Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Anciano , Humanos , Masculino , Persona de Mediana Edad
19.
Eur J Pharmacol ; 417(3): 239-48, 2001 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-11334856

RESUMEN

Cyclooxygenase-1 and cyclooxygenase-2 mRNAs and proteins and prostaglandin E(2) production are evaluated in a rat model of inflammation in which Escherichia coli lipopolysaccharide is intraperitoneally injected or intravesically instilled into the bladder. While cyclooxygenase-1 mRNA and protein and cyclooxygenase-2 mRNA do not change in bladders treated with lipopolysaccharide, cyclooxygenase-2 protein is elevated in bladders from rats intravesically instilled with lipopolysaccharide or phosphate buffered saline (PBS) or intraperitoneally injected with lipopolysaccharide. Urinary prostaglandin E(2) levels and prostaglandin E(2) synthesis in bladder particulates are elevated by intravesical instillation and intraperitoneal injection of lipopolysaccharide. The nitric oxide donor, S-nitroso-N-acetyl-D,L-penicillamine, increases prostaglandin E(2) synthesis in bladders from lipopolysaccharide intravesically instilled and intraperitoneally injected rats. Lipopolysaccharide increases prostaglandin E(2) synthesis by increasing cyclooxygenase-2 protein levels in rat bladder and prostaglandin E(2) synthesis may be further elevated by increases in nitric oxide caused by an up-regulation of inducible nitric oxide synthase (iNOS).


Asunto(s)
Dinoprostona/metabolismo , Isoenzimas/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Regulación hacia Arriba , Vejiga Urinaria/metabolismo , Vejiga Urinaria/patología , Administración Intravesical , Animales , Western Blotting , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/farmacología , Dinoprostona/biosíntesis , Dinoprostona/orina , Femenino , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Inyecciones Intraperitoneales , Isoenzimas/antagonistas & inhibidores , Isoenzimas/genética , Lipopolisacáridos/administración & dosificación , Lipopolisacáridos/farmacología , Proteínas de la Membrana , Ácido Niflúmico/farmacología , Nitratos/farmacología , Óxido Nítrico/metabolismo , Óxido Nítrico/orina , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico Sintasa/metabolismo , Oxidantes/farmacología , Penicilamina/análogos & derivados , Penicilamina/farmacología , Prostaglandina-Endoperóxido Sintasas/genética , Protaminas/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Regulación hacia Arriba/efectos de los fármacos , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/enzimología
20.
J Urol ; 165(6 Pt 1): 1964-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11371890

RESUMEN

PURPOSE: Robotics in surgery is a recent innovation. This technology offers a number of attractive features in laparoscopy. It overcomes the difficulties with fixed port sites by restoring all 6 degrees of freedom at the instrument tips, provides new possibilities for miniaturization of surgical tasks and allows remote controlled surgery. We investigated the applicability of remote controlled robotic surgery to laparoscopic radical prostatectomy. MATERIALS AND METHODS: Our previous experience with laparoscopic prostatectomy served as a basis for adapting robotic surgery to this procedure. A surgeon at a different location who activated the tele-manipulators of the da Vinci* robotic system performed all steps of the intervention. A scrub nurse and second surgeon who stood at patient side had limited roles to port and instrument placement, exposure of the operative field, assistance in hemostasis and removal of the operative specimen. Our patient was a 63-year-old man presenting with a T1c tumor discovered on 1 positive sextant biopsy with a 3+3 Gleason score and 7 ng./ml. preoperative serum prostate specific antigen. RESULTS: The robot provided an ergonomic surgical environment and remarkable dexterity enhancement. Operating time was 420 minutes, and the hospital stay lasted 4 days. The bladder catheter was removed 3 days postoperatively, and 1 week later the patient was fully continent. Pathological examination showed a pT3a tumor with negative margins. CONCLUSIONS: Robotically assisted laparoscopic radical prostatectomy is feasible. This new technology enhances surgical dexterity. Further developments in this field may have new applications in laparoscopic tele-surgery.


Asunto(s)
Laparoscopía/métodos , Prostatectomía/métodos , Robótica , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/cirugía
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...