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1.
J Chem Phys ; 135(24): 244508, 2011 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-22225170

RESUMEN

Elastic models imply that the energy expended for a flow event in ultra-viscous matter coincides with the elastic work required for deforming and re-arranging the environment of the moving entity. This is quite promising for explaining the strong non-Arrhenius behavior of dynamic quantities of fragile super-cooled liquids. We argue that the activation volume obtained from dielectric relaxation and light-scattering experiments for super-cooled liquids should scale with the Gibbs free energy of activation, with a proportionality constant determined by the isothermal bulk modulus and its pressure derivative, as described by an earlier thermodynamic elastic model. For certain super-cooled liquids the bulk compression transpiring in the local environment, as governed by the isothermal bulk modulus, play a significant role in the reorientational dynamics, with far-field density fluctuations and volume changes avoided by shear deformation.

2.
Obes Surg ; 13(1): 132-5, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12630628

RESUMEN

BACKGROUND: Technical improvements of laparoscopic bariatric procedures are important to minimize operative time and increase safety and simplicity. METHODS: A modification is described of the "classic" Mason-MacLean vertical banded gastroplasty (VBG), performed by laparoscopy, with wedge resection of the gastric fundus, thus avoiding the time-consuming and technically difficult gastro-gastrostomy window. RESULTS: The technique used was simple and safe, and required less operative time than the "classic" method, without serious intra- or postoperative complications. Weight loss in 18 patients who underwent the modified laparoscopic VBG and were followed-up for 1 year was equal to that achieved in patients who underwent open VBG at our Institution. Gastro-gastric fistula was not observed in upper GI barium studies performed 12 months postoperatively. CONCLUSION: The modified technique is preferable when lap-VBG is indicated for surgical treatment of morbidly obese patients.


Asunto(s)
Gastroplastia/métodos , Laparoscopía/métodos , Humanos , Obesidad Mórbida/cirugía , Cuidados Posoperatorios , Mallas Quirúrgicas , Grapado Quirúrgico
3.
Obes Surg ; 22(7): 1104-9, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22527590

RESUMEN

BACKGROUND: The continuing need for simple, safe, and effective procedures led us to design a new operation for treating morbid obesity. METHODS: Thirty-two patients underwent our novel procedure, sleeve gastrectomy plus side-to-side jejunoileal anastomosis (SG plus), and were followed for 6 to 24 months. A matched cohort of 32 patients underwent sleeve gastrectomy over the same period and was used as the control group. Weight loss, comorbidity outcomes, and the duodenum to cecum transit time after a gastrografin swallow, performed at postoperative day 4, were compared. RESULTS: There were no deaths and no major perioperative complications. Three patients developed long-term complications requiring surgical intervention (intestinal obstruction, nausea-vomiting, and hypoalbuminemia). In the SG plus group, a 77.8 % excess weight loss was achieved at 12 months postoperatively, which was significantly better (p < 0.01) than the 67 % observed in the control group. The comorbidity outcomes, particularly diabetes resolution, were also significantly superior in the SG plus patients. The duodenum to cecum transit time of 11 min in the SG plus group was significantly shorter (p < 0.01) than the 31 min observed in the control group. CONCLUSIONS: Sleeve gastrectomy plus side-to-side jejunoileal anastomosis appears to be a simple, considerably safe, and effective procedure for treating obesity and its metabolic comorbidities.


Asunto(s)
Anastomosis en-Y de Roux , Tránsito Gastrointestinal , Gastroplastia , Íleon/cirugía , Yeyuno/cirugía , Obesidad Mórbida/cirugía , Adulto , Anciano , Anastomosis en-Y de Roux/efectos adversos , Anastomosis en-Y de Roux/métodos , Índice de Masa Corporal , Ciego/fisiopatología , Estudios de Cohortes , Comorbilidad , Duodeno/fisiopatología , Femenino , Gastroplastia/métodos , Humanos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/sangre , Obesidad Mórbida/fisiopatología , Resultado del Tratamiento , Pérdida de Peso
4.
Ann Gastroenterol ; 24(4): 325-327, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-24713779

RESUMEN

A 35-year-old lady was admitted to our Department due to fever and symptoms from the respiratory and gastrointestinal system. She was recently diagnosed with eosinophilic gastroenteritis and had been on steroids until two months prior to admission. Legionella pneumophila pneumonia was diagnosed and targeted therapy was initiated. The combined approach to the two entities is discussed as well as the options for maintenance therapy.

5.
Eur J Radiol ; 69(3): 425-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19101103

RESUMEN

PURPOSE: To assess mesenteric lymph nodes in patients with different Crohn's disease subtypes identified on MR Enteroclysis. MATERIALS AND METHODS: Thirty-four patients, categorized into three different Crohn's disease subgroups, underwent MR Enteroclysis. A high resolution coronal true FISP sequence with fat saturation was applied to assess mesenteric lymph node anatomic distribution, size and shape. Their enhancement ratio (ER) was calculated by dividing signal intensity of each node to signal intensity of nearby vessel on T1 weighted FLASH images, acquired 75 s after intravenous administration of gadolinium. A one-way analysis of variance statistical test was applied to investigate any significant differences regarding mean ER among different disease subgroups. RESULTS: Two hundred and eighty-three mesenteric lymph nodes were assessed, 231 in patients with active inflammatory (AI) disease, 36 in patients with fibrostenotic (FS) and 16 in patients with fistulizing/perforating (FP) disease. Maximum and minimum diameters were 3.2 and 0.3 cm, respectively. 75% of the lymph nodes presented with an oval shape. The majority were identified as being ileocolic (34%) and paracolic (31%). AI subgroup lymph nodes presented with the highest mean ER (0.783+/-0.17) followed by FP (0.706+/-0.1) and FS subgroup (0.652+/-0.17) lymph nodes. The differences in mean values of ER of mesenteric lymph nodes between AI and FS subtypes were statistically significant (p<0.0001), while mean ER between nodes of FP and the other two subtypes did not present statistically significant differences. CONCLUSION: ER of mesenteric lymph nodes identified on MR Enteroclysis may vary across different subtypes of Crohn's disease. Such differences may be valuable in clinical practice.


Asunto(s)
Medios de Contraste/administración & dosificación , Enfermedad de Crohn/diagnóstico , Aumento de la Imagen/métodos , Intestinos/patología , Enfermedades Linfáticas/diagnóstico , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
6.
Surg Today ; 37(6): 506-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17522772

RESUMEN

Cutaneous malignant melanoma (MM) often metastasizes to the gastrointestinal (GI) tract; however, primary MM of the small intestine is a controversial diagnosis. We report the case of a 76-year-old woman found to have a primary MM in the ileum. After clinical evaluation, the radiological workup, which included magnetic resonance enteroclysis (MRE), revealed a large polypoid intraluminal tumor. She underwent laparotomy and the lesion was excised. Histological examination of the resected specimen revealed morphological and immunohistochemical characteristics of MM and a detailed postoperative examination failed to identify a primary lesion on the skin, anus, oculus, or any other site. The patient died of brain metastasis 6 months after surgery. According to our review of the literature, this is the first case of primary MM of the small intestine diagnosed with the help of MRE.


Asunto(s)
Neoplasias del Íleon/complicaciones , Intususcepción/etiología , Melanoma/complicaciones , Anciano , Neoplasias Encefálicas/secundario , Resultado Fatal , Femenino , Humanos , Neoplasias del Íleon/patología , Melanoma/patología , Melanoma/secundario
7.
Eur Radiol ; 16(9): 1915-25, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16673093

RESUMEN

The purpose of this study was to compare MR enteroclysis (MRE) with conventional enteroclysis (CE) in patients with small intestinal Crohn's disease. Fifty-two consecutive patients with known or suspected Crohn's disease underwent MR and conventional enteroclysis, which was considered the gold standard. Eleven imaging features, classified in three groups, mucosal, transmural and extraintestinal, were subjectively evaluated by two experienced radiologists. MRE and CE were in full agreement in revealing, localizing and estimating the length of all involved segments of the small bowel. The sensitivity of MRE for the detection of superficial ulcers, fold distortion and fold thickening was 40, 30 and 62.5%, respectively. The sensitivity of MRE for the detection of deep ulcers, cobble-stoning pattern, stenosis and prestenostic dilatation was 89.5, 92.3, 100 and 100%, respectively. Additional findings demonstrated on MRE images included fibrofatty proliferation in 15 cases and mesenteric lymphadenopathy in 19 cases. MRE strongly correlates with CE in the detection of individual lesions expressing small intestinal Crohn's disease. It provides additional information from the mesenteries; however, its capability to detect subtle lesions is still inferior to conventional enteroclysis.


Asunto(s)
Enfermedad de Crohn/diagnóstico , Intestino Delgado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Cateterismo , Medios de Contraste/administración & dosificación , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Intestino Delgado/patología , Masculino , Persona de Mediana Edad , Radiografía , Sensibilidad y Especificidad
8.
Eur Radiol ; 12(11): 2651-8, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12386753

RESUMEN

Magnetic resonance enteroclysis (MRE) is an emerging technique for the evaluation of small bowel abnormalities. Adequate luminal distention, achieved by the administration of iso-osmotic water solution through a nasojejunal catheter, in combination with ultrafast sequences, such as single-shot turbo spin echo, true fast imaging with steady precession, half-Fourier acquired single-shot turbo spin echo, and 3D fast low-angle shot, results in excellent anatomic demonstration of the small bowel. Magnetic resonance fluoroscopy can be performed during MRE examination and might be useful in studying low-grade stenosis or motility-related disorders. Magnetic resonance enteroclysis is very promising in detecting the number and extent of involved small bowel segments in patients with Crohn's disease, and in disclosing lumen narrowing and extramural manifestations and complications of the disease. Initial experience shows that MRE is very efficient in the diagnosis of small bowel tumors and can be used in the evaluation of small bowel obstruction.


Asunto(s)
Intestino Delgado/patología , Imagen por Resonancia Magnética , Medios de Contraste , Enfermedad de Crohn/patología , Enema , Humanos , Intubación Gastrointestinal , Presión Osmótica
9.
Eur Radiol ; 14(6): 1017-24, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15057562

RESUMEN

Every single imaging finding that can be disclosed on conventional and MR enteroclysis was correlated with the Crohn's disease activity index (CDAI). Nineteen consecutive patients with Crohn's disease underwent colon endoscopy and both conventional and MR enteroclysis examinations. Seventeen MR imaging findings and seven conventional enteroclysis findings were ranked on a four-point grading scale and correlated with CDAI, with a value of 150 considered as the threshold for disease activity. Six patients had active disease in the colon according to colon endoscopy. In the remaining 13 patients, the presence of deep ulcers ( P=0.002), small bowel wall thickening ( P=0.022) and gadolinium enhancement of mesenteric lymph nodes ( P=0.014) identified on MR enteroclysis images were strongly correlated to disease activity. The product of deep ulcers and enhancement of lymph node ranks identified on MR enteroclysis were the optimum combination for discriminating active from non-active disease ( F-test: 55.95, P<0.001). Additionally, the ranking of deep ulcers on conventional enteroclysis provided statistically significant differences between active and non-active patients ( F-test: 14.12, P=0.004). Abnormalities strongly suggestive of active Crohn's disease can be disclosed on MR enteroclysis examinations and may provide pictorial information for local inflammatory activity.


Asunto(s)
Enfermedad de Crohn/diagnóstico , Intestino Delgado/patología , Imagen por Resonancia Magnética/métodos , Adulto , Sulfato de Bario/administración & dosificación , Colonoscopía , Enfermedad de Crohn/patología , Femenino , Gadolinio , Humanos , Masculino , Persona de Mediana Edad
10.
Eur Radiol ; 13(3): 448-52, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12594545

RESUMEN

The objective of this study was to compare inversion recovery turbo 2D fast low-angle shot (FLASH) and 3D FLASH sequences for fecal-tagged MR colonography studies. Fifteen consecutive patients with indications for colonoscopy underwent MR colonography with fecal tagging. An inversion recovery turbo-FLASH sequence was applied and compared in terms of artifacts presence, efficiency for masking residual stool, and colonic wall conspicuity with a fat-saturated 3D FLASH sequence. Both sequences were acquired following administration of paramagnetic contrast agent. Contrast-to-noise ratio and relative contrast between colonic wall and lumen were calculated and compared for both sequences. Turbo 2D FLASH provided fewer artifacts, higher efficiency for masking the residual stool, and colonic wall conspicuity equivalent to 3D FLASH. An inversion time of 10 ms provided homogeneously low signal intensity of the colonic lumen. Contrast to noise between colonic wall and lumen was significantly higher in the 3D FLASH images, whereas differences in relative contrast were not statistically significant. An optimized inversion-recovery 2D turbo-FLASH sequence provides better fecal tagging results and should be added to the 3D FLASH sequence when designing dark-lumen MR colonography examination protocols.


Asunto(s)
Enfermedades del Colon/diagnóstico por imagen , Enfermedades del Colon/patología , Colonografía Tomográfica Computarizada/métodos , Intensificación de Imagen Radiográfica , Sulfato de Bario , Colonoscopía , Medios de Contraste , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Masculino , Cooperación del Paciente , Probabilidad , Muestreo , Sensibilidad y Especificidad , Estadísticas no Paramétricas
11.
Eur Radiol ; 13(7): 1522-8, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12835963

RESUMEN

The aim of this study was to determine ovarian dose, effective dose and associated radiogenic risks from hysterosalpingography (HSG), and to provide data for the estimation of radiogenic risks related to HSG studies performed in any laboratory. The fluoroscopy time, number of radiographs taken and entrance surface dose were measured in a series of 78 consecutive patients undergoing HSG as part of their infertility work-up. Organ-dose values per radiograph and per minute of fluoroscopy were separately determined using an anthropomorphic phantom and thermoluminescence dosimetry. The radiogenic risk for deleterious effects on a possible future embryo and the radiogenic risk for cancer induction on the patient undergoing HSG were estimated. The average HSG procedure in our laboratory involves a mean fluoroscopic time of 0.3 min and a mean number of radiographs of 3.2. The dose to female gonads from an average HSG procedure was 2.7 mGy and the patient effective dose was 1.2 mSv. The risk for radiogenic anomalies in a future embryo of the woman undergoing an average HSG procedure and the risk for radiogenic fatal cancer induction in the exposed woman were estimated to be less than 10(-3) of the correspondent nominal risks. Radiation risks from a typical HSG are low, but they may be elevated if fluoroscopic and/or radiographic exposures are prolonged for any reason. Present data allow the estimation of radiogenic risks associated with HSG procedures performed in other laboratories with use of different equipment, screening time and number of radiographs taken.


Asunto(s)
Histerosalpingografía , Ovario/efectos de la radiación , Dosis de Radiación , Anomalías Inducidas por Radiación/epidemiología , Adolescente , Adulto , Femenino , Fluoroscopía , Humanos , Histerosalpingografía/efectos adversos , Infertilidad Femenina/diagnóstico por imagen , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/epidemiología , Protección Radiológica , Factores de Riesgo , Factores de Tiempo
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