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1.
Infection ; 42(4): 661-8, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24647770

RESUMEN

OBJECTIVES: We wanted to assess the diagnostic accuracy of urinary dipstick testing in excluding catheter-associated urinary tract infection (CAUTI) in intensive care unit (ICU) patients with fever or hypothermia. METHODS: This was a prospective observational cohort study in a medical-surgical ICU. Patients with new-onset fever >38.3 °C or hypothermia <36 °C at least 48 h after urinary catheter insertion were included over a 2-year period. At each episode, a urinary dipstick test and a urine culture were performed as the criterion standard. Extensive microbiological investigations for extra-urinary infections were performed also. The performances of various urinary dipstick result combinations in ruling out CAUTI were compared based on the likelihood ratios (LR+ and LR-). RESULTS: Symptomatic CAUTI was diagnosed in 31 (24.4 %) of the 127 included patients (195 episodes of fever or hypothermia). LR+ was best for combined leukocyte esterase-positive and nitrite-positive dipstick results (overall population: 14.91; 95 % confidence interval [95 % CI], 5.53-40.19; patients without urinary symptoms: 15.63; 95 % CI, 5.76-42.39). LR- was best for either leukocyte esterase-positive or nitrite-positive dipstick results (overall population: 0.41; 95 % CI, 0.57-0.65; patients without urinary symptoms, 0.36; 95 % CI, 0.21-0.60). CONCLUSIONS: Urinary dipstick testing at the bedside does not help to rule out symptomatic CAUTI in medical or surgical ICU patients with fever or hypothermia.


Asunto(s)
Infecciones Relacionadas con Catéteres/diagnóstico , Fiebre de Origen Desconocido/etiología , Hipotermia/etiología , Sistemas de Atención de Punto , Infecciones Urinarias/diagnóstico , Orina/química , Adulto , Hidrolasas de Éster Carboxílico/análisis , Estudios de Cohortes , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Técnicas Microbiológicas , Persona de Mediana Edad , Nitritos/análisis , Estudios Prospectivos , Orina/microbiología
2.
Cancer Radiother ; 25(4): 350-357, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33618909

RESUMEN

PURPOSE: To investigate clinical outcome and predicting factors of local failures in patients with colorectal cancer treated for unresectable liver metastases with stereotactic body radiation therapy (SBRT). METHODS AND MATERIALS: We restrospectively reviewed the medical records of 67 patients treated with the Cyberknife SBRT system for 99 hepatic metastases between January 2007 and December 2015 in our center. In total, 37.5 to 54.0Gy in 3 to 5 fractions were prescribed to the 80% isodose line. Local control (LC), intrahepatic progression incidence, Progression-Free Survival (PFS), Overall Survival (OS) and toxicity were evaluated. RESULTS: The median follow-up was 47 months (IQR, 28-59 months). The median OS was 53 months, the 2-year OS and PFS rates were 81.4% and 54.0%. The 1- and 2-year LC rates were 86.6% and 72.4%. In the multivariate analysis, the degree of differentiation was the only prognostic factor for LC (HR 0.31, 95% CI, 0.10-0.98, P=0.046). Margin expansion>5mm was not associated with a better LC (HR 0.72, 95% CI, 0.38-1.37, P=0.317). Performans Status≥2 (HR 3.27, 95% CI, 1.07-9.98, P=0.038), chemotherapy for metastases before SBRT (HR 0.36, 95% CI, 0.18-0.75, P=0.006) and regional lymph node at diagnosis (HR 2.19, 95% CI, 1.09-4.43, P=0.029) were independent prognostic factors for OS. We report 2 cases of grade≥3 toxicity (3.0%) - one grade 3 acute nausea and one grade 3 late gastric ulcer. CONCLUSION: Stereotactic body radiation therapy is an effective and well-tolerated treatment that allow high LC for liver metastases from colorectal cancer during the first two years. A prescription dose of 45Gy in 3 fractions to the 80% isodose line with a risk adapted schedule to respect Organ At Risk constraints allows a low rate of toxicity.


Asunto(s)
Neoplasias Colorrectales/patología , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundario , Radiocirugia/métodos , Anciano , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Supervivencia sin Progresión , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
3.
Digestion ; 82(1): 42-6, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20203511

RESUMEN

Invasive intraductal papillary-mucinous neoplasms (IPMNs) of the pancreas may be associated with pancreaticogastric fistulas as shown by case reports. We report the case of a benign IPMN associated with pancreaticogastric and pancreaticoduodenal fistulas. A 70-year-old woman was admitted with intestinal obstruction. Computed tomography and MRI showed a large dilatation of the main pancreatic duct (>1 cm) with intraductal nodules, and pancreaticogastric and pancreaticoduodenal fistulas. Several features in imaging were present to support a malignant IPMN, so that the patient underwent a pancreaticoduodenectomy. The histopathological examination of the surgical specimen showed a benign IPMN. This case proves that a benign IPMN can cause pancreaticogastric and pancreaticoduodenal fistulas, probably resulting from mechanical factors.


Asunto(s)
Adenocarcinoma Mucinoso/complicaciones , Carcinoma Ductal Pancreático/complicaciones , Carcinoma Papilar/complicaciones , Enfermedades Duodenales/etiología , Fístula Gástrica/etiología , Fístula Intestinal/etiología , Fístula Pancreática/etiología , Neoplasias Pancreáticas/complicaciones , Adenocarcinoma Mucinoso/cirugía , Anciano , Carcinoma Ductal Pancreático/cirugía , Carcinoma Papilar/cirugía , Enfermedades Duodenales/cirugía , Femenino , Fístula Gástrica/cirugía , Humanos , Fístula Intestinal/cirugía , Fístula Pancreática/cirugía , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía
4.
J Radiol ; 91(7-8): 759-68, 2010.
Artículo en Francés | MEDLINE | ID: mdl-20814359

RESUMEN

Liver calcifications have been extensively described on plain radiographs, either from KUB or angiography examinations. On the other hand, their characteristics are seldom reported on cross-sectional imaging: they are frequently considered as non-specific compared to multiple other imaging features. However, clinical practice demonstrates that in specific situations (such as parasitic infections and calcified metastases), the presence of calcifications may be a determining factor in avoiding misdiagnosis with potential deleterious effects to the patient. Both CT and US can detect a large number of "benign" calcifications without associated focal lesion and knowledge of their imaging features is useful to avoid unnecessary additional imaging work-up. A review of the literature and a series of 100 cases of liver calcifications on CT are presented to review the imaging features of calcified liver lesions and isolated liver calcifications without associated focal lesion.


Asunto(s)
Calcinosis/diagnóstico por imagen , Hepatopatías/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Calcinosis/epidemiología , Calcinosis/etiología , Calcinosis/patología , Femenino , Humanos , Incidencia , Hígado/patología , Hepatopatías/epidemiología , Hepatopatías/etiología , Hepatopatías/patología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
5.
Med Mal Infect ; 50(2): 213-225, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30266432

RESUMEN

Severe malaria accounts for approximately 10% of all cases of imported malaria in France; cases are mainly due to Plasmodium falciparum, while other Plasmodium species are possible but uncommon (P. vivax, P. knowlesi, P. malariae, and P. ovale). On the basis of WHO criteria for endemic areas, the French criteria defining severe imported malaria in adults have been progressively adapted to the European healthcare level. Management of severe imported malaria is a diagnostic and treatment emergency and must be initially conducted in the intensive care unit. Anti-infective treatment is now based on intravenous artesunate, which must be available in every hospital of the country likely to receive severe imported malaria patients. Intravenous quinine is thus used as a second-line treatment and is restricted to limited indications. Critical care management of organ failure is essential, particularly in patients presenting with very severe malaria. To date, no adjunctive therapy (including exchange transfusion) has demonstrated clear beneficial effects.


Asunto(s)
Enfermedades Transmisibles Importadas/diagnóstico , Enfermedades Transmisibles Importadas/terapia , Malaria/diagnóstico , Malaria/terapia , Adulto , Humanos , Guías de Práctica Clínica como Asunto , Índice de Severidad de la Enfermedad
6.
Biophys J ; 96(5): 2009-22, 2009 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-19254561

RESUMEN

This study aims at improving the understanding of mechanisms responsible for cell sensitivity to extracellular environment. We explain how substrate mechanical properties can modulate the force regulation of cell sensitive elements primarily adhesion sites. We present a theoretical and experimental comparison between two radically different approaches of the force regulation of adhesion sites that depends on their either stationary or dynamic behavior. The most classical stationary model fails to predict cell sensitivity to substrate stiffness whereas the dynamic model predicts extracellular stiffness dependence. This is due to a time dependent reaction force in response to actomyosin traction force exerted on cell sensitive elements. We purposely used two cellular models, i.e., alveolar epithelial cells and alveolar macrophages exhibiting respectively stationary and dynamic adhesion sites, and compared their sensitivity to theoretical predictions. Mechanical and structural results show that alveolar epithelial cells exhibit significant prestress supported by evident stress fibers and lacks sensitivity to substrate stiffness. On the other hand, alveolar macrophages exhibit low prestress and exhibit sensitivity to substrate stiffness. Altogether, theory and experiments consistently show that adhesion site dynamics and cytoskeleton prestress control cell sensitivity to extracellular environment with an optimal sensitivity expected in the intermediate range.


Asunto(s)
Células Epiteliales/fisiología , Espacio Extracelular/fisiología , Macrófagos Alveolares/fisiología , Modelos Biológicos , Actomiosina/fisiología , Animales , Adhesión Celular/fisiología , Línea Celular , Células Cultivadas , Colágeno Tipo I/química , Simulación por Computador , Citocalasina D/metabolismo , Módulo de Elasticidad , Células Epiteliales/citología , Humanos , Macrófagos Alveolares/citología , Magnetismo , Alveolos Pulmonares/citología , Ratas , Ratas Sprague-Dawley , Mucosa Respiratoria/citología , Torque
7.
J Cell Biol ; 146(6): 1319-32, 1999 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-10491394

RESUMEN

To propel itself in infected cells, the pathogen Shigella flexneri subverts the Cdc42-controlled machinery responsible for actin assembly during filopodia formation. Using a combination of bacterial motility assays in platelet extracts with Escherichia coli expressing the Shigella IcsA protein and in vitro analysis of reconstituted systems from purified proteins, we show here that the bacterial protein IcsA binds N-WASP and activates it in a Cdc42-like fashion. Dramatic stimulation of actin assembly is linked to the formation of a ternary IcsA-N-WASP-Arp2/3 complex, which nucleates actin polymerization. The Arp2/3 complex is essential in initiation of actin assembly and Shigella movement, as previously observed for Listeria monocytogenes. Activation of N-WASP by IcsA unmasks two domains acting together in insertional actin polymerization. The isolated COOH-terminal domain of N-WASP containing a verprolin-homology region, a cofilin-homology sequence, and an acidic terminal segment (VCA) interacts with G-actin in a unique profilin-like functional fashion. Hence, when N-WASP is activated, its COOH-terminal domain feeds barbed end growth of filaments and lowers the critical concentration at the bacterial surface. On the other hand, the NH(2)-terminal domain of N-WASP interacts with F-actin, mediating the attachment of the actin tail to the bacterium surface. VASP is not involved in Shigella movement, and the function of profilin does not require its binding to proline-rich regions.


Asunto(s)
Actinas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas Contráctiles , Proteínas del Citoesqueleto , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al GTP/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Factores de Transcripción/metabolismo , Proteína 2 Relacionada con la Actina , Proteína 3 Relacionada con la Actina , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Plaquetas/citología , Plaquetas/metabolismo , Encéfalo/citología , Encéfalo/metabolismo , Bovinos , Moléculas de Adhesión Celular/metabolismo , Proteínas de Unión al ADN/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/fisiología , Células HeLa , Humanos , Listeria/fisiología , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Movimiento , Mutación , Proteínas del Tejido Nervioso/química , Fosfoproteínas/metabolismo , Polímeros , Profilinas , Prolina/metabolismo , Shigella flexneri/genética , Shigella flexneri/fisiología , Factores de Transcripción/genética , Proteína Neuronal del Síndrome de Wiskott-Aldrich , Proteína de Unión al GTP cdc42 de Saccharomyces cerevisiae
8.
J Cell Biol ; 136(6): 1307-22, 1997 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-9087445

RESUMEN

Actin-binding proteins of the actin depolymerizing factor (ADF)/cofilin family are thought to control actin-based motile processes. ADF1 from Arabidopsis thaliana appears to be a good model that is functionally similar to other members of the family. The function of ADF in actin dynamics has been examined using a combination of physical-chemical methods and actin-based motility assays, under physiological ionic conditions and at pH 7.8. ADF binds the ADP-bound forms of G- or F-actin with an affinity two orders of magnitude higher than the ATP- or ADP-Pi-bound forms. A major property of ADF is its ability to enhance the in vitro turnover rate (treadmilling) of actin filaments to a value comparable to that observed in vivo in motile lamellipodia. ADF increases the rate of propulsion of Listeria monocytogenes in highly diluted, ADF-limited platelet extracts and shortens the actin tails. These effects are mediated by the participation of ADF in actin filament assembly, which results in a change in the kinetic parameters at the two ends of the actin filament. The kinetic effects of ADF are end specific and cannot be accounted for by filament severing. The main functionally relevant effect is a 25-fold increase in the rate of actin dissociation from the pointed ends, while the rate of dissociation from the barbed ends is unchanged. This large increase in the rate-limiting step of the monomer-polymer cycle at steady state is responsible for the increase in the rate of actin-based motile processes. In conclusion, the function of ADF is not to sequester G-actin. ADF uses ATP hydrolysis in actin assembly to enhance filament dynamics.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Actinas/fisiología , Movimiento Celular , Proteínas de Microfilamentos/fisiología , Proteínas del Tejido Nervioso/fisiología , Citoesqueleto de Actina/ultraestructura , Factores Despolimerizantes de la Actina , Actinas/química , Adenosina Trifosfato/fisiología , Secuencia de Aminoácidos , Animales , Arabidopsis/genética , Biopolímeros , Plaquetas/citología , Movimiento Celular/efectos de los fármacos , Destrina , Humanos , Cinética , Listeria monocytogenes/citología , Listeria monocytogenes/efectos de los fármacos , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/farmacología , Modelos Biológicos , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/farmacología , Fosforilación , Proteínas de Plantas/genética , Unión Proteica , Procesamiento Proteico-Postraduccional , Conejos , Alineación de Secuencia , Homología de Secuencia de Aminoácido
9.
J Cell Biol ; 144(6): 1245-58, 1999 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-10087267

RESUMEN

Intracellular propulsion of Listeria monocytogenes is the best understood form of motility dependent on actin polymerization. We have used in vitro motility assays of Listeria in platelet and brain extracts to elucidate the function of the focal adhesion proteins of the Ena (Drosophila Enabled)/VASP (vasodilator-stimulated phosphoprotein) family in actin-based motility. Immunodepletion of VASP from platelet extracts and of Evl (Ena/VASP-like protein) from brain extracts of Mena knockout (-/-) mice combined with add-back of recombinant (bacterial or eukaryotic) VASP and Evl show that VASP, Mena, and Evl play interchangeable roles and are required to transform actin polymerization into active movement and propulsive force. The EVH1 (Ena/VASP homology 1) domain of VASP is in slow association-dissociation equilibrium high-affinity binding to the zyxin-homologous, proline-rich region of ActA. VASP also interacts with F-actin via its COOH-terminal EVH2 domain. Hence VASP/ Ena/Evl link the bacterium to the actin tail, which is required for movement. The affinity of VASP for F-actin is controlled by phosphorylation of serine 157 by cAMP-dependent protein kinase. Phospho-VASP binds with high affinity (0.5 x 10(8) M-1); dephospho-VASP binds 40-fold less tightly. We propose a molecular ratchet model for insertional polymerization of actin, within which frequent attachment-detachment of VASP to F-actin allows its sliding along the growing filament.


Asunto(s)
Actinas/fisiología , Moléculas de Adhesión Celular/fisiología , Proteínas Contráctiles , Proteínas del Citoesqueleto , Proteínas de Unión al ADN/fisiología , Listeria monocytogenes/fisiología , Fosfoproteínas/fisiología , Actinas/química , Actinas/ultraestructura , Animales , Secuencia de Bases , Sitios de Unión , Plaquetas/metabolismo , Encéfalo/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/fisiología , Moléculas de Adhesión Celular/genética , Cartilla de ADN/genética , Proteínas de Unión al ADN/genética , Listeria monocytogenes/genética , Ratones , Ratones Noqueados , Proteínas de Microfilamentos/fisiología , Microscopía Electrónica , Modelos Biológicos , Movimiento/fisiología , Fosfoproteínas/genética , Profilinas , Unión Proteica , Proteínas/genética , Proteínas/fisiología
10.
J Radiol ; 90(7-8 Pt 2): 905-17, 2009.
Artículo en Francés | MEDLINE | ID: mdl-19752830

RESUMEN

For a long time, imaging of the biliary tract after surgical procedures was performed with invasive procedures such as endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography. Due to recent advances in diagnostic imaging, non-invasive techniques are now favored. While US remains the initial imaging modality, it is frequently followed by CT and/or MRCP. Image interpretation should always be performed in keeping with clinical and laboratory findings as well as the type of surgical procedure. The most appropriate imaging modality is selected based on these data. In patients with jaundice or biliary tract stenosis, MRCP, with use of an optimal technique and 3D acquisition, is the imaging modality of choice. In non-jaundiced patients with non-distended biliary tract and suspected bile leak, MRCP should be completed by the injection of a liver-specific contrast agent with biliary excretion to achieve non-invasive biliary tract opacification. In patients with malignancy, CT is preferred due to its high spatial resolution and ability to demonstrate small anastomotic tumor recurrences. CT should also be performed in patients with suspected hepatic artery or portal vein injury in addition to biliary tract injury or to detect distant complications.


Asunto(s)
Conductos Biliares/cirugía , Procedimientos Quirúrgicos del Sistema Biliar , Pancreatocolangiografía por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anastomosis Quirúrgica/efectos adversos , Colangiografía , Colecistectomía Laparoscópica , Colelitiasis/etiología , Conducto Colédoco/cirugía , Medios de Contraste , Ácido Edético/análogos & derivados , Femenino , Humanos , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/diagnóstico por imagen , Fosfato de Piridoxal/análogos & derivados , Reoperación
11.
Biomed Mater Eng ; 18(1 Suppl): S105-18, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18334728

RESUMEN

The sensitivity of alveolar macrophages to substrate properties has been described in a recent paper (Féréol et al., Cell Motil. Cytoskel. 63 (2006), 321-340). It is presently re-analyzed in terms of F-actin structure (assessed from 3D-reconstructions in fixed cells) and mechanical properties (assessed by Magnetic Twisting Cytometry experiments in living cells) of cortical and deep cytoskeleton structures for rigid plastic (Young Modulus: 3 MPa) or glass (70 MPa) substrates and a soft (approximately 0.1 kPa) confluent monolayer of alveolar epithelial cells. The cortical cytoskeleton component (lowest F-actin density) is represented by the rapid and softer viscoelastic compartment while the deep cytoskeleton component (intermediate F-actin density) is represented by the slow and stiffer compartment. Stiffness of both cortical and deep cytoskeleton is significantly decreased when soft confluent monolayer of alveolar epithelial cells replace the rigid plastic substrate while F-actin reconstructions reveal a consistent actin cytoskeleton remodeling observable on both cytoskeleton components.


Asunto(s)
Actinas/fisiología , Citoesqueleto/fisiología , Macrófagos/fisiología , Mecanotransducción Celular/fisiología , Modelos Biológicos , Alveolos Pulmonares/citología , Alveolos Pulmonares/fisiología , Animales , Células Cultivadas , Simulación por Computador , Femenino , Masculino , Ratas , Ratas Sprague-Dawley
12.
J Radiol ; 89(3 Pt 2): 413-35; quiz 436-7, 2008 Mar.
Artículo en Francés | MEDLINE | ID: mdl-18408642

RESUMEN

Imaging plays a pivotal role in the management of GI tract cancers for diagnosis, characterization, locoregional staging, metastatic work-up and follow-up during and after curative or palliative treatment. The imaging protocols should be optimized and reproducible because of their impact on therapy. Thoracic, abdominal and pelvic CT is the cornerstone of the imaging work-up, optimized and tailored to the specific GI segment involved, requiring good GI tract distension. Image interpretation of native axial and reformatted multiplanar images is routinely performed. In specific cases, additional targeted imaging with US or MRI or whole body imaging with PET/CT or MRI may be valuable. PET/CT is a complement to morphological imaging. PET allows detection of lesions otherwise undetected on morphological imaging, usually due to poor contrast with surrounding tissues, and characterization of known lesions. PET/CT is best used as an integral part of a comprehensive imaging work-up. Radiologist and nuclear medicine specialist provide complementary information. Each must be familiar with the clinical questions at hand and related stakes, and advantages and limitations of each modality to optimize treatment as part of a multidisciplinary management approach.


Asunto(s)
Neoplasias Gastrointestinales/diagnóstico por imagen , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Humanos , Masculino
13.
J Radiol ; 89(6): 765-74, 2008 Jun.
Artículo en Francés | MEDLINE | ID: mdl-18641563

RESUMEN

To illustrate the CT and MR imaging features of alveolar echinococcosis, a rare disease that is endemic in the northeast of France. Hepatic and extrahepatic manifestations are presented. Fibrous and necrotic features are demonstrated on MR. Calcifications are demonstrated on CT. Accurate imaging diagnosis will exclude tumors (cholangiocarcinoma, cystadenoma, fibrous metastases) and avoid unnecessary biopsy.


Asunto(s)
Equinococosis/diagnóstico , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Equinococosis Hepática/diagnóstico , Humanos
14.
J Radiol ; 89(12): 1935-40, 2008 Dec.
Artículo en Francés | MEDLINE | ID: mdl-19106852

RESUMEN

PURPOSE: To compare two methods of post processing cardiac CT data to measure global ventricular function. Materials and methods. Retrospective study where three readers measured the end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) of the right (n=22) and left (n=44) ventricles, using a 2D method (extrapolated volumetric method, EVM) and a 3D method (direct volumetric method, DVM) after cardiac CT with retrospective ECG gating. Inter- and intraobserver agreement were calculated based on the intraclass correlation coefficient (ICC) with 95% confidence interval (CI95%), and results obtained with each method were compared using the student t test for paired samples. RESULTS: Inter- and intraobserver reproducibility were very good for both methods, with ICC ranging between 0.694 and 0.992, without significant difference. For the left ventricle, EDV, ESV and EF were 16653 ml, 8351 ml and 5415% for DVM et de 20361 ml, 11558 ml and 4613% for EVM respectively. Right ventricular values were 15247 ml, 7534 ml, 5013% and 17253 ml, 9940 ml, 439% (p<0,0001). CONCLUSION: The very good inter- and intraobserver reproducibility for both methods validate their use in clinical practice. Volume measurements with DVM are always inferior to volumes with EDM, with inverse relationship for EF measurements.


Asunto(s)
Imagenología Tridimensional , Tomografía Computarizada por Rayos X , Función Ventricular , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
15.
Neuroscience ; 144(2): 522-30, 2007 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-17067745

RESUMEN

The pineal hormone melatonin nocturnal synthesis feeds back on the suprachiasmatic nuclei (SCN), the central circadian clock. Indeed, daily melatonin injections in free-running rats resynchronize their locomotor activity to 24 h. However, the molecular mechanisms underlying this chronobiotic effect of the hormone are poorly understood. The endogenous circadian machinery involves positive and negative transcriptional feedback loops implicating different genes (particularly period (Per) 1-3, Clock, Bmal1, cryptochrome (Cry) 1-2). While CLOCK:BMAL1 heterodimer activates the rhythmic transcription of per and cry genes, the PER and CRY proteins inhibit the CLOCK:BMAL1 complex. In previous studies, we observed that the immediate resetting effect of a melatonin injection at the end of the subjective day on the SCN circadian activity did not directly involve the above-mentioned clock genes. Recently, nuclear orphan receptors (NORs) have been presented as functional links between the regulatory loops of the molecular clock. These NORs bind to a retinoic acid receptor-related orphan receptor response element (RORE) domain and activate (RORalpha) or repress (REV-ERBalpha) bmal1 expression. In this study, we investigated whether melatonin exerts its chronobiotic effects through transcriptional regulation of these transcription factors. We monitored roralpha, rorbeta and rev-erbalpha messenger RNA (mRNA) expression levels by quantitative in situ hybridization, up to 36 h following a melatonin injection at circadian time (CT) 11.5. Results clearly showed that, while roralpha was not affected by melatonin, the hormone partially prevented the decrease of the rorbeta mRNA expression observed in control animals during the first hours following the injection. The major result is that the rev-erbalpha mRNA expression rhythm was 1.3+/-0.8-h phase-advanced in melatonin-treated animals during the first subjective night following the melatonin administration. Moreover, the bmal1 mRNA expression was 1.9+/-0.9-h phase-shifted in the second subjective night following the melatonin injection. These results clearly suggest that the NOR genes could be the link between the chronobiotic action of melatonin and the core of the molecular circadian clock.


Asunto(s)
Depuradores de Radicales Libres/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Melatonina/farmacología , ARN Mensajero/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Núcleo Supraquiasmático/efectos de los fármacos , Animales , Ritmo Circadiano/fisiología , Depuradores de Radicales Libres/sangre , Masculino , Melatonina/sangre , Ratas , Ratas Wistar
16.
J Radiol ; 88(4): 531-40, 2007 Apr.
Artículo en Francés | MEDLINE | ID: mdl-17464251

RESUMEN

Mangafodipir trisodium (Teslascan) is a hepatobiliary contrast agent that provides noninvasive opacification of the bile ducts. Using this contrast medium combined with a T1-weighted gradient echo enhanced sequence provides functional imaging of the bile ducts. Second-intention MRI was obtained after the usual morphological study of the bile ducts using heavily T2-weighted sequences (SS-FSE Te eff long and SS FSE Te eff short). This method can detect many biliary duct anomalies: biliary leakage in the postoperative context, mapping of bile ducts and the gallbladder in the search for anatomical variants, analysis of biliodigestive or biliobiliary anastomoses, or a dynamic study of bile secretion and excretion. Opacification of the bile ducts has only been possible until now with invasive tests aggravated by a certain co-morbidity rate and their functional study using biliary scintigraphy limited by mediocre spatial resolution. This new possibility provides access not only to morphological imaging, but also to functional imaging with excellent spatial resolution.


Asunto(s)
Enfermedades de las Vías Biliares/diagnóstico , Medios de Contraste , Ácido Edético/análogos & derivados , Enfermedades de la Vesícula Biliar/diagnóstico , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Manganeso , Fosfato de Piridoxal/análogos & derivados , Adulto , Anciano , Anastomosis Quirúrgica/efectos adversos , Enfermedades de los Conductos Biliares/diagnóstico , Conductos Biliares Intrahepáticos/anatomía & histología , Quiste del Colédoco/diagnóstico , Imagen Eco-Planar/métodos , Femenino , Humanos , Imagenología Tridimensional/métodos , Trasplante de Hígado/efectos adversos , Donadores Vivos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Factores de Tiempo
17.
J Radiol ; 88(2): 235-50, 2007 Feb.
Artículo en Francés | MEDLINE | ID: mdl-17372551

RESUMEN

The objective of the CT-enteroclysis is to distend the entire small intestine equally and sufficiently using a nasojejunal probe and an enteroclysis catheter for administration of a neutral opacifying agent. Today this is the best radiological method available to explore the small intestine because of its good spatial resolution and the rapidity of the exam. It is a high-performance exam when searching for transmural and extramural pathologies, in particular small tumoral lesions. It remains less effective in the exploration of anomalies of the lumen's mucosal lining, contrary to videocapsule endoscopy and the double-balloon enteroscope. It has been recognized that the CT-enteroclysis is a high-performance examination that should replace the small-bowel follow-through exam. However, there are undeniable disadvantages: higher does of radiation, patient discomfort during placement of the enteroclysis catheter, false-positive results, long interpretation time, and the impossibility of exploring the endoluminal aspect of the intestinal mucosal lining. All radiologists should therefore become familiar with the problems involved with this exam and its signs and patterns, which are illustrated in this pictorial review.


Asunto(s)
Neoplasias Duodenales/diagnóstico por imagen , Neoplasias del Íleon/diagnóstico por imagen , Neoplasias del Yeyuno/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Humanos
18.
J Radiol ; 88(7-8 Pt 2): 1036-47, 2007.
Artículo en Francés | MEDLINE | ID: mdl-17762833

RESUMEN

Knowledge of the histological features of different components of a liver lesion greatly assists radiologists because it provides understanding of the correspondingimaging features. The imaging characteristics of lesions depend on variations of the extracellular architecture, mainly surrounding stromal tissue. Until histological imaging techniques become available, cellular analysis relies on optical microscopy and immunohistochemistry. Recent advances in imaging techniques now provide additional information on lesions due to improved spatial, temporal and contrast resolution. Correct interpretation of these imaging features should improve diagnosis.


Asunto(s)
Diagnóstico por Imagen , Hepatopatías/diagnóstico , Hígado/patología , Calcinosis/diagnóstico , Calcinosis/patología , Medios de Contraste , Quistes/diagnóstico , Quistes/patología , Hígado Graso/diagnóstico , Hígado Graso/patología , Hemorragia/diagnóstico , Hemorragia/patología , Humanos , Aumento de la Imagen/métodos , Inmunohistoquímica , Hígado/irrigación sanguínea , Absceso Hepático/diagnóstico , Absceso Hepático/patología , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/patología , Hepatopatías/patología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética , Microscopía , Neovascularización Patológica/diagnóstico , Neovascularización Patológica/patología , Factores de Tiempo , Tomografía Computarizada por Rayos X
19.
Abdom Radiol (NY) ; 42(7): 1880-1887, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28357531

RESUMEN

PURPOSE: The first reports of hepatic steatosis following pancreaticoduodenectomy (PD) were published several years ago; however, clear risk factors remain to be identified. Therefore, the aim of this study was to identify the risk factors for hepatic steatosis post-PD. METHODS: We studied 90 patients who had undergone PD between September 2005 and January 2015. The inclusion criteria were as follows: available unenhanced CT within one month before PD and at least one unenhanced CT acquisition between PD and chemotherapy initiation. Using scanners, we studied the liver and spleen density as well as the surface areas of visceral (VF) and subcutaneous fat (SCF). These variables were previously identified by univariate and multivariate analyses. RESULTS: Hepatic steatosis occurred in 25.6% of patients at 45.2 days, on average, post-PD. Among the patients with hepatic steatosis, the average liver density was 52 HU before PD and 15.1 HU post-PD (p < 0.001). The Patients with hepatic steatosis lost more VF (mean, 28 vs. 11 cm2) and SCF (28.8 vs. 13.7 cm2) (p < 0.01 and p = 0.01, respectively). Portal vein resection and extensive lymph node dissection were independent risk factors in the multivariate analysis (odds ratio [OR] 5.29, p = 0.009; OR 3.38, p = 0.04, respectively). CONCLUSION: Portal vein resection and extensive lymph node dissection are independent risk factors for post-PD hepatic steatosis.


Asunto(s)
Hígado Graso/diagnóstico por imagen , Escisión del Ganglio Linfático , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/cirugía , Pancreaticoduodenectomía , Complicaciones Posoperatorias/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Hígado Graso/epidemiología , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X
20.
Eur J Radiol ; 93: 265-272, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28668425

RESUMEN

PURPOSE: The aim of the present study was to estimate the incidence of very early hepatic metastases (HMs) (<6 months) and their imaging patterns after cephalic duodenopancreatectomy (CDP) for periampullary carcinoma (excluding duodenal carcinoma) and to identify their associated risk factors. METHODS: From January 2003 to June 2016, all patients who underwent surgical treatment for periampullary carcinoma by CDP at our institution and with adequate pre- and postoperative CT scans were included. Univariate and multivariate logistic regressions were performed to determine factors associated with very early HM and recurrence. RESULTS: Of the 132 patients included retrospectively, 27 (20.5%) patients developed HMs. The mean time to diagnosis of HM was 103.9±55.2days. HMs were multiple in 81.4% of cases and bilobar in 59.3% of cases; their mean maximum size was 16.7±12.7mm. In univariate logistic analysis, lymphovascular emboli were significantly associated with HM (p=0.02). No independent risk factors for HM were found in multivariate analysis. In multivariate logistic analysis, two independent risk factors were identified for the occurrence of early recurrence: tumor size >23mm on preoperative CT scan (OR: 3.3; 95% CI: [1.2-9.3]; p=0.02) and tumor differentiation (poor vs. good: OR 15.5; 95 CI [1.5-158.3]; moderate vs. good: OR: 17.1; 95% CI: [1.9-154.4]; p=0.04). CONCLUSIONS: Nearly one in five patients developed HM after CDP within 6 months with a highly consistent pattern. A thorough preoperative assessment, combining CT scan and MRI with a delay of less than three weeks before surgery, appears essential. A routine systematic postoperative CT scan at 8 weeks is also required prior to initiating adjuvant chemotherapy. The type of surgical intervention does not seem to be a risk factor, although the risk of HM occurrence appears to be related to the lymphovascular invasion of the tumor and maybe its degree of differentiation, elements not assessable by imaging.


Asunto(s)
Adenocarcinoma/secundario , Neoplasias Duodenales/cirugía , Neoplasias Hepáticas/secundario , Neoplasias Pancreáticas/cirugía , Adenocarcinoma/cirugía , Adulto , Anciano , Quimioterapia Adyuvante , Femenino , Humanos , Incidencia , Modelos Logísticos , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/cirugía , Neoplasias Peritoneales/secundario , Estudios Retrospectivos , Factores de Riesgo , Tomografía Computarizada por Rayos X
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