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2.
Obes Rev ; 17(8): 724-34, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27125603

RESUMEN

BACKGROUND: A quantitative content analysis of research on parenting and childhood obesity was conducted to describe the recent literature and to identify gaps to address in future research. METHODS: Studies were identified from multiple databases and screened according to an a priori defined protocol. Eligible studies included non-intervention studies, published in English (January 2009-December 2015) that focused on parenting and childhood obesity and included parent participants. RESULTS: Studies eligible for inclusion (N = 667) focused on diet (57%), physical activity (23%) and sedentary behaviours (12%). The vast majority of studies used quantitative methods (80%) and a cross-sectional design (86%). Few studies focused exclusively on fathers (1%) or included non-residential (1%), non-biological (4%), indigenous (1%), immigrant (7%), ethnic/racial minority (15%) or low-socioeconomic status (19%) parents. DISCUSSION: While results illustrate that parenting in the context of childhood obesity is a robust, global and multidisciplinary area of inquiry, it is also evident that the vast majority of studies are conducted among Caucasian, female, biological caregivers living in westernized countries. Expansion of study foci and design is recommended to capture a wider range of caregiver types and obesity-related parenting constructs, improve the validity and generalizability of findings and inform the development of culture-specific childhood obesity prevention interventions and policies. © 2016 World Obesity.


Asunto(s)
Responsabilidad Parental/psicología , Obesidad Infantil/psicología , Dieta , Etnicidad , Estudios de Evaluación como Asunto , Ejercicio Físico , Conductas Relacionadas con la Salud , Humanos , Obesidad Infantil/prevención & control , Conducta Sedentaria
3.
Acta Anaesthesiol Scand ; 56(9): 1183-90, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22834537

RESUMEN

PURPOSE: The aim was to test the feasibility of protocol-driven fluid removal with continuous renal replacement therapy (CRRT) in patients in whom standard fluid balance prescription did not result in substantial negative fluid balances. MATERIALS AND METHODS: In 10 mechanically ventilated patients with sepsis or signs of inflammation and acute kidney injury [age 65 (48-78 years; median, range), simplified acute physiology score II 66 (39-116)], fluid removal was guided by mean arterial pressure (MAP), cardiac index (CI), mixed venous oxygen saturation (SvO(2)), lactate/base excess, peripheral circulation, and filling pressures, and adjusted hourly with the goal to maximize volume removal for up to 3 days. RESULTS: Fluid removal rates during the 3 days before and during the study period [66 (36-72) h] were 11 (-30 to +36) ml/kg/day and -59 (-85 to -31) ml/kg/day, respectively (P = 0.002). In 12% of a total of 594 fluid removal rate evaluations, fluid removal had to be decreased or stopped. Most frequent reasons leading to decreasing fluid removal were (n, % of all instances, median lowest value from all patients): SvO(2) (44, 28%, 59%), MAP (36, 23%, 57 mmHg), CI (26, 17%, 2.4 l/min/m(2)), low peripheral temperature (22, 14%, 'cold'). Overall, systemic hemodynamics remained stable throughout the study period. CONCLUSIONS: In these patients, protocolized fluid removal with CRRT was associated with large negative fluid balances.


Asunto(s)
Lesión Renal Aguda/terapia , Enfermedad Crítica/terapia , Terapia de Reemplazo Renal/métodos , APACHE , Lesión Renal Aguda/fisiopatología , Anciano , Circulación Sanguínea/fisiología , Gasto Cardíaco/fisiología , Cuidados Críticos , Interpretación Estadística de Datos , Estudios de Factibilidad , Femenino , Hemodinámica/fisiología , Humanos , Inflamación/terapia , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Respiración con Presión Positiva , Respiración Artificial , Insuficiencia Respiratoria/terapia , Sepsis/terapia
4.
Rofo ; 184(6): 548-55, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22434368

RESUMEN

PURPOSE: In the diagnosis and risk assessment of obesity, both the amount and distribution of adipose tissue compartments are critical factors. We present a hybrid method for the quantitative measurement of human body fat compartments. MATERIALS AND METHODS: MRI imaging was performed on a 1.5 T scanner. In a pre-processing step, the images were corrected for bias field inhomogeneity. For segmentation and recognition a hybrid algorithm was developed to automatically differentiate between different adipose tissue compartments. The presented algorithm is designed with a combination of shape and intensity-based techniques. To incorporate the presented algorithm into the clinical routine, we developed a graphical user interface. Results from our methods were compared with the known volume of an adipose tissue phantom. To evaluate our method, we analyzed 40 clinical MRI scans of the abdominal region. RESULTS: Relatively low segmentation errors were found for subcutaneous adipose tissue (3.56 %) and visceral adipose tissue (0.29 %) in phantom studies. The clinical results indicated high correlations between the distribution of adipose tissue compartments and obesity. CONCLUSION: We present an approach that rapidly identifies and quantifies adipose tissue depots of interest. With this method examination and analysis can be performed in a clinically feasible timeframe.


Asunto(s)
Grasa Abdominal/patología , Algoritmos , Distribución de la Grasa Corporal , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Obesidad Abdominal/diagnóstico , Programas Informáticos , Artefactos , Índice de Masa Corporal , Estudios de Factibilidad , Femenino , Humanos , Masculino , Obesidad Mórbida/diagnóstico , Fantasmas de Imagen , Sensibilidad y Especificidad , Estadística como Asunto , Interfaz Usuario-Computador
5.
Magn Reson Med ; 67(3): 691-700, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21858861

RESUMEN

Quantification of molecular diffusion with steady state free precession (SSFP) is complicated by the fact that diffusion effects accumulate over several repetition times (TR) leading to complex signal dependencies on transverse and longitudinal magnetization paths. This issue is commonly addressed by setting TR > T(2), yielding strong attenuation of all higher modes, except of the shortest ones. As a result, signal attenuation from diffusion becomes T(2) independent but signal-to-noise ratio (SNR) and sequence efficiency are remarkably poor. In this work, we present a new approach for fast in vivo steady state free precession diffusion-weighted imaging of cartilage with TR << T(2) offering a considerable increase in signal-to-noise ratio and sequence efficiency. At a first glance, prominent coupling between magnetization paths seems to complicate quantification issues in this limit, however, it is observed that diffusion effects become rather T(2) (ΔD ≈ 1/10 ΔT(2)) but not T(1) independent (ΔD ≈ 1/2 ΔT(1)) for low flip angles α ≈ 10 - 15°. As a result, fast high-resolution (0.35 × 0.35 - 0.50 × 0.50 mm(2) in-plane resolution) quantitative diffusion-weighted imaging of human articular cartilage is demonstrated at 3.0 T in a clinical setup using estimated T(1) and T(2) or a combination of measured T(1) and estimated T(2) values.


Asunto(s)
Cartílago Articular/anatomía & histología , Imagen de Difusión por Resonancia Magnética/métodos , Articulación de la Rodilla/anatomía & histología , Simulación por Computador , Humanos , Aumento de la Imagen/métodos , Imagenología Tridimensional , Modelos Teóricos , Sensibilidad y Especificidad
6.
Ann Cardiol Angeiol (Paris) ; 58(5): 272-8, 2009 Nov.
Artículo en Francés | MEDLINE | ID: mdl-19819421

RESUMEN

AIM OF THE STUDY: To compare definite endocarditis (DE) and possible endocarditis (PE) according to the Duke criteria, in a monocentric cohort of 45 patients. METHOD: From the registers of the Cardiology Department and medical database of the hospital informatic department, 45 cases of endocarditis are colliged, 29DE and 16PE. RESULTS: DE age is 66 years, PE age is 74 years, (p<0,02), 17 male (59%) in DE, eight in PE, 21 (72%) DE have a preexisting cardiopathy versus 15 (94%) PE, seven native valve and six prosthetic valve in PE, 11 native valve and nine prosthetic valve in DE. Twenty-six (90%) DE and 16 (100%) have fever, 14 (48%) DE and nine (56%) PE have a cardiac failure, one DE (3%) and 14 (87%) have no echographic sign of endocarditis (transthoracic echo or transthoracic and transesophagal echo) (p<0.001). Blood cultures are positive in 23DE (79%), and 14 (87%) PE (NS) Streptococcus and Enterococcus are the most common bacterial species (62%) in the two groups. Treatment duration is 64 days for DE and 43 days for PE, hospitalisation duration is 33 days for the DE and 27 days in PE. CONCLUSIONS: PE group and DE group are similar concerning fever cardiac failure, preexisting cardiopathy, blood cultures and bacterial species. PE group is older than DE group, echography is more often negative in PE group. A patient with a preexisting valvulopathy and a septicemia without echographic sign of endocarditis is the most frequent clinical pattern in PE.


Asunto(s)
Endocarditis/diagnóstico , Anciano , Femenino , Humanos , Masculino
7.
Fetal Diagn Ther ; 24(3): 203-10, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18753758

RESUMEN

OBJECTIVE: To investigate the influence of several magnetic resonance imaging (MRI) sequences on amniotic fluid temperature and intrauterine sound pressure. MATERIAL AND METHODS: Temperature and sound pressure measurements during MRI (1.5 T) in pregnant ewes were done. Linear levels and third octave band spectra were compared. RESULTS: No significant changes in the temperature of amniotic fluid were observed. Intrauterine summation levels reached peak levels up to 103.0 dB(A) before starting the MRI sequence and levels up to 116.0 dB(A) during a real-time sequence. Evaluating the octave band spectra, peak levels did not exceed 100.0 dB(L). CONCLUSIONS: Our delimited data revealed no harm for the fetus by an increase in amniotic fluid temperature or hazards for the fetal auditory system by different MRI sequences.


Asunto(s)
Imagen por Resonancia Magnética/efectos adversos , Ovinos/fisiología , Sonido , Temperatura , Acústica , Animales , Femenino , Feto/fisiología , Audición/fisiología , Embarazo , Medición de Riesgo , Espectrografía del Sonido
8.
Minerva Anestesiol ; 72(1-2): 21-36, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16407804

RESUMEN

Pulmonary capillary pressure (Pcap) is the predominant force that drives fluid out of the pulmonary capillaries into the interstitium. Increasing hydrostatic capillary pressure is directly proportional to the lung's transvascular filtration rate, and in the extreme leads to pulmonary edema. In the pulmonary circulation, blood flow arises from the transpulmonary pressure gradient, defined as the difference between pulmonary artery (diastolic) pressure and left atrial pressure. The resistance across the pulmonary vasculature consists of arterial and venous components, which interact with the capacitance of the compliant pulmonary capillaries. In pathological states such as acute respiratory distress syndrome, sepsis, and high altitude or neurogenic lung edema, the longitudinal distribution of the precapillary arterial and the postcapillary venous resistance varies. Subsequently, the relationship between Pcap and pulmonary artery occlusion pressure (PAOP) is greatly variable and Pcap can no longer be predicted from PAOP. In clinical practice, PAOP is commonly used to guide fluid therapy, and Pcap as a hemodynamic target is rarely assessed. This approach is potentially misleading. In the presence of a normal PAOP and an increased pressure gradient between Pcap and PAOP, the tendency for fluid leakage in the capillaries and subsequent edema development may substantially be underestimated. Tho-roughly validated methods have been developed to assess Pcap in humans. At the bedside, measurement of Pcap can easily be determined by analyzing a pressure transient after an acute pulmonary artery occlusion with the balloon of a Swan-Ganz catheter.


Asunto(s)
Permeabilidad Capilar/fisiología , Circulación Pulmonar/fisiología , Algoritmos , Humanos , Edema Pulmonar/fisiopatología , Edema Pulmonar/terapia , Respiración Artificial , Resistencia Vascular
10.
Radiology ; 221(3): 818-21, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11719684

RESUMEN

An infected cyst in autosomal dominant polycystic kidney disease was identified with a combined positron emission tomographic (PET) and computed tomographic (CT) system, an experimental setup mimicking an integrated CT-PET scanner. Image fusion of fluorine 18 fluorodeoxyglucose PET and CT images allowed exact localization of the infected cyst among many cysts identified on previous CT and magnetic resonance images. Confirmation was obtained instantly, followed by CT-guided percutaneous puncture. Integrated imaging systems hold promise for direct PET-guided puncture of areas of increased fluorodeoxyglucose uptake by using the anatomic accuracy of CT.


Asunto(s)
Infecciones por Escherichia coli/terapia , Procesamiento de Imagen Asistido por Computador , Riñón Poliquístico Autosómico Dominante/terapia , Punciones , Radiografía Intervencional , Tomografía Computarizada de Emisión , Tomografía Computarizada por Rayos X , Infecciones por Escherichia coli/complicaciones , Infecciones por Escherichia coli/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Humanos , Riñón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Riñón Poliquístico Autosómico Dominante/complicaciones , Riñón Poliquístico Autosómico Dominante/diagnóstico por imagen , Punciones/métodos , Radiofármacos
11.
Plant Physiol ; 127(2): 416-25, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11598217

RESUMEN

Elucidation of the mechanisms involved in long-distance water transport in trees requires knowledge of the water distribution within the sapwood and heartwood of the stem as well as of the earlywood and latewood of an annual ring. X-ray computed tomography is a powerful tool for measuring density distributions and water contents in the xylem with high spatial resolution. Ten- to 20-year-old spruce (Picea abies L. KARST.) and oak (Quercus robur) trees grown in the field were used throughout the experiments. Stem and branch discs were collected from different tree heights, immediately deep frozen, and used for the tomographic determinations of spatial water distributions. Results are presented for single-tree individuals, demonstrating heartwood and sapwood distribution throughout their entire length as well as the water relations in single annual rings of both types of wood. Tree rings of the sapwood show steep water gradients from latewood to earlywood, whereas those of the heartwood reflect water deficiency in both species. Although only the latest two annual rings of the ringporous species are generally assumed to transport water, we found similar amounts of water and no tyloses in all rings of the oak sapwood, which indicates that at least water storage is important in the whole sapwood.


Asunto(s)
Picea/fisiología , Quercus/fisiología , Transporte Biológico , Densitometría , Modelos Biológicos , Tallos de la Planta/fisiología , Tomografía Computarizada por Rayos X/métodos , Árboles/fisiología , Agua/metabolismo
12.
Magn Reson Imaging ; 19(5): 649-57, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11672623

RESUMEN

Transverse relaxation rates R2(*) were measured in subjects performing a motor task using a segmented EPI double gradient echo sequence (TE = 23/70 ms) with five different voxel sizes between 1.8 mm(3) and 41.7 mm(3). An analysis of the errors involved in the calculation of the change of the transverse relaxation rate--DeltaR2(*) and of the consequences of defining an arbitrary threshold of statistical significance in the data analysis was performed. Correlations between the magnitude of the BOLD effect and the significance level on one hand and between the transverse relaxation time at rest and its change under activation on the other, both referenced in the literature, can be understood as a consequence of this procedure. Analysing histograms of parameter changes rather than average values alone allows for an estimate of the contribution of false positive voxels. Furthermore, while the averaged signal change increases in proportion to the selection threshold the histograms of activated voxels remain insensitive to the latter.


Asunto(s)
Nivel de Alerta/fisiología , Encéfalo/fisiología , Aumento de la Imagen , Imagen por Resonancia Magnética , Consumo de Oxígeno/fisiología , Desempeño Psicomotor/fisiología , Adulto , Atención/fisiología , Encéfalo/anatomía & histología , Mapeo Encefálico , Imagen Eco-Planar , Femenino , Humanos , Masculino , Valores de Referencia
13.
J Trauma ; 49(4): 704-9, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11038089

RESUMEN

BACKGROUND: Magnetic resonance imaging (MRI) is rarely used for preoperative assessment of shotgun injuries because of concerns of displacing the possibly ferromagnetic foreign body within the surrounding tissue. METHODS: A total of 56 different projectiles underwent MRI testing for ferromagnetism and imaging quality in vitro and in pig carcasses with a commercially available 1.5-MRI scan. Image quality was compared with that of computed tomographic scans. RESULTS: Projectiles with ferromagnetic properties can be distinguished easily from nonferromagnetic ones by pretesting the motion of an identical projectile within the MRI coil. When ferromagnetic projectiles were excluded, MRI yielded the more precise images compared with other imaging techniques. Projectile localization and associated soft tissue injuries were visualized without artifacts in all cases. CONCLUSIONS: When ferromagnetic foreign bodies are excluded by pretesting their properties within the MRI with a comparative projectile, MRI portends an excellent imaging procedure for assessing the extent of injury and planning the removal by surgery.


Asunto(s)
Imagen por Resonancia Magnética , Heridas por Arma de Fuego/patología , Animales , Artefactos , Armas de Fuego , Humanos , Técnicas In Vitro , Magnetismo , Porcinos , Tomografía Computarizada por Rayos X
14.
Naunyn Schmiedebergs Arch Pharmacol ; 354(4): 491-7, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8897453

RESUMEN

Effects of Evans blue and four derivatives as well as of trypan blue and four derivatives, mostly smaller fragments but two compounds with an additional ethylene bridge in the center of the molecule, were studied on contractions of the rat vas deferens elicited by alpha, beta-methylene ATP (alpha, beta-MeATP; mediated by P2X-purinoceptors), relaxations of the carbachol-precontracted guinea-pig taenia coli elicited by adenosine 5'-O-(2-thiodiphosphate) (ADP beta S; mediated by P2Y-purinoceptors), and the degradation of ATP by rat vas deferens tissue. All compounds shifted the concentration-response curve of alpha, beta-MeATP in the rat vas deferens to the right, and most compounds increased the maximum of the curve. Each member of the Evans blue series was similar in potency to the corresponding member of the trypan blue series. Where three concentrations were tested, the Arunlakshana-Schild regression was linear, and the slope did not differ from 1. The apparent Kd values were between 0.8 and 385 microM. In the guinea-pig taenia coli, only the members of the trypan blue group were relatively potent, shifting the concentration-response curve of ADP beta S to the right in a surmountable manner. In 2 of 3 cases where three concentrations were tested, the slope of the Arunlakshana-Schild regression was lower than 1. Apparent Kd values in the trypan blue group were between 5.2 and 324 microM. The removal of ATP from the medium by vas deferens tissue was decreased mainly by the members of the Evans blue group, with IC25% values between 13 and 158 (in 1 case > 1000) microM. The results indicate that the position of the sulphonate residues at the terminal naphthalene rings of these compounds hardly influences P2X purinoceptor affinity but greatly influences P2Y affinity and ecto-nucleotidase blockade. Among active compounds, apparent purinoceptor affinity and ecto-nucleotidase blockade increase with the size of the molecules up to Evans blue and trypan blue themselves; introduction of a central ethylene bridge does not result in a further gain in potency. NH01, the desmethyl derivative of Evans blue, seems to be interesting because it is the compound with the highest P2X- versus P2Y-selectivity presently available.


Asunto(s)
Adenosina Trifosfatasas/efectos de los fármacos , Azul de Evans/análogos & derivados , Azul de Evans/farmacología , Antagonistas del Receptor Purinérgico P2 , Azul de Tripano/análogos & derivados , Azul de Tripano/farmacología , Adenosina Difosfato/análogos & derivados , Adenosina Difosfato/farmacología , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Animales , Colon/efectos de los fármacos , Colon/metabolismo , Cobayas , Masculino , Contracción Muscular/efectos de los fármacos , Relajación Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/metabolismo , Ratas , Relación Estructura-Actividad , Tionucleótidos/farmacología , Conducto Deferente/efectos de los fármacos , Conducto Deferente/metabolismo
15.
Biochemistry ; 29(40): 9395-402, 1990 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-2248952

RESUMEN

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from chicken was expressed in and purified from Escherichia coli. To investigate the physical basis of possible protein stabilization strategies, the effect of substitutions of glycine residues by alanine in helical regions was determined. One Gly to Ala substitution (G316A) located in the central core of the subunit was found to strongly stabilize the protein, while the other mutations are neutral or destabilize the protein. The effect seen for the stabilizing mutant in irreversible heat denaturation correlates with the first transition in folding equilibrium experiments that is observable by fluorescence, but not with the one detected by circular dichroism measurements or in dilution-induced dissociation experiments. The stabilizing effect of a Gly to Ala substitution therefore does not seem to be caused by an entropic effect on the unfolded state. Rather, an internal cavity is filled by the substitution G316A, probably stabilizing the native state. In large oligomeric proteins, imperfect packing may be a frequent cause of limited stability.


Asunto(s)
Gliceraldehído-3-Fosfato Deshidrogenasas/química , Alanina/química , Animales , Pollos , Dicroismo Circular , Estabilidad de Medicamentos , Escherichia coli/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Glicina/química , Cinética , Conformación Proteica , Desnaturalización Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrometría de Fluorescencia
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