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Martínez Quesada M Trujillo Berraquero F Almendro Delia M Hidalgo Urbano R Cruz Fernández JM 《Revista espa?ola de cardiología》2005,58(4):450-452
Primary cardiac tumors are infrequent and usually benign. They can manifest as dyspnea, chest pain, palpitations, sudden death, peripheral embolism, cyanosis, or general symptoms. They are sometimes an incidental finding in an asymptomatic patient. We describe a 33-year-old man who was seen because of dyspnea and palpitations. Transthoracic echocardiography revealed, on the lateral wall of the left ventricle, an intramyocardial mass that was successfully resected surgically. The pathologic diagnosis was hamartoma of mature cardiac myocytes. We discuss the usefulness of imaging techniques for identifying cardiac masses. 相似文献
74.
Durán Ferreras A Duque San Juan P Durán Ferreras E Ponce Herrera C Acevedo Bañez I Cambil Molina T Castro Montaño J Rodríguez de Quesada y Tello B 《Revista espanola de medicina nuclear》2004,23(1):39-41
We present the case of a 78 year old man admitted to the hospital with progressive memory disorder. Neuropsychological examination showed inability to recognize familiar faces (prosopagnosia). MRI documented cortical atrophy, which did not explain the neurological deficit. CT did not show abnormalities. Most patients with prosopagnosia present brain atrophy, as they are more than 65 years old. Scanning by SPECT revealed hypoperfusion in the right parietotemporal region, which was worse in a later examination. 相似文献
75.
Quesada E Delgado J Gajate C Mollinedo F Acuña AU Amat-Guerri F 《Journal of medicinal chemistry》2004,47(22):5333-5335
Edelfosine (ET-18-OCH3), a synthetic antitumor ether lipid, is taken up by malignant but not by normal cells, triggering apoptosis in a large variety of human tumor cells. The synthesis of the first fluorescent edelfosine analogue (6), with apoptotic activity comparable to that of the parent drug, is described. Fluorescence microscopy experiments show that 6 selectively labels human cancer cells, accumulating into specific domains of the plasma membrane. 相似文献
76.
Peripapillary glial cells of the chick are a special type of glia, not only because of their position, forming a boundary between the retina on one side and the optic nerve head (ONH) and the pecten on the other, but also because although they have the same orientation and similar shape as the retinal Müller cell (a type of radial glia) and express common markers for these cells and astrocytes, they do not express glutamine synthetase (GS) or carbonic anhydrase C (CA-C), enzymes intensely expressed by Müller cells and astrocytes. In this study, we present further molecular characterization of these cells, using immunohistochemistry techniques. We show that peripapillary glial cells express a novel neuron antigen, 3BA8, that in the adult retina is located only in one neuron type (the amacrine cell) and in the inner plexiform layer (IPL). They also express an antigen specific to myelin and oligodendrocytes, MOSP, and a glial antigen, 3CB2, expressed by radial glia and astrocytes throughout the CNS. The study of the developmental expression of these three antigens in the peripapillary glial cell territory shows different spatiotemporal labeling patterns: 3CB2 and 3BA8 are expressed much earlier (embryonic days E3 and E5, respectively) than MOSP (E12), and during a developmental window (E6-E10) 3BA8 labels the peripapillary glial cells intensely and does not label the ONH or the optic nerve (ON), which are labeled later. The expression of 3CB2 is much more intense in the peripapillary glial cells than in Müller cells from early stages of development up to E16, and the expression of MOSP starts earlier in the peripapillary glial cells than in the Müller cells and is maintained with much higher intensity in the peripapillary glial cells throughout development. These findings show that Müller and peripapillary glial cells follow independent courses of differentiation, which together with the fact that the peripapillary glial cells express molecules typical of neurons, oligodendrocytes, radial glia, and astrocytes are evidence that peripapillary glial cells are a unique type of glia in the CNS. 相似文献
77.
Synthesis, activity, and molecular modeling studies of novel human aldose reductase inhibitors based on a marine natural product 总被引:5,自引:0,他引:5
de la Fuente JA Manzanaro S Martín MJ de Quesada TG Reymundo I Luengo SM Gago F 《Journal of medicinal chemistry》2003,46(24):5208-5221
Aldose reductase (ALR2) has been implicated in the etiology of diabetic complications, including blindness. Because of the limited number of currently available drugs for the prevention of these long-term complications, the discovery of new ALR2 inhibitors appears highly desirable. In this study, a polybrominated diphenyl ether (1) naturally occurring in a marine sponge was found to inhibit recombinant human ALR2 with an IC(50) of 6.4 microM. A series of polyhalogenated analogues that were synthesized and tested in vitro to explore the structure-activity relationships displayed various degrees of inhibitory activity. The most active compounds were also capable of preventing sorbitol accumulation inside human retinal cells. In this cell-based assay, the most potent synthesized analogue (16) showed a 17-fold increase in inhibitory activity compared to that of sorbinil (IC(50) = 0.24 vs 4 microM). A molecular representation of human ALR2 in complex with the natural product was built using homology modeling, automated docking, and energy refinement methods. AMBER parameters for the halogen atoms were derived and calibrated using condensed phase molecular dynamics simulations of fluorobenzene, chlorobenzene, and bromobenzene. Inhibitor binding is proposed to cause a conformational change similar to that recently reported for zenarestat. A free energy perturbation thermodynamic cycle allowed us to assess the importance of a crucial bromine atom that distinguishes the active lead compound from a much less active close natural analogue. Remarkably, the spatial location of this bromine atom is equivalent to that occupied by the only bromine atom present in zenarestat. 相似文献
78.
Calvet X Quesada M Roselló M Salceda F Sanfeliu I Dalmau B Gil M 《Alimentary pharmacology & therapeutics》2003,17(5):727-731
BACKGROUND: Helicobacter pylori infection may lead to peptic ulcer disease, and causes significant morbidity in patients with cirrhosis. The measurement of H. pylori antigens in human stools has been proposed as a valuable, non-invasive, diagnostic tool. A number of tests have recently been commercialized. However, very few data are available on their reliability in patients with cirrhosis. AIM: To evaluate the usefulness of three new tests--HpSA (Meridian Diagnostics Inc., Cincinnati, OH, USA), Simple H. pyl (OPERON S.A., Zaragoza, Spain) and FemtoLab H. pylori (Connex, Martinsried, Germany)--in the diagnosis of H. pylori infection in cirrhotic patients. METHODS: H. pylori infection was determined in 79 cirrhotic patients (48 men, 31 women; age range, 29-82 years; mean, 62 +/- 11 years) by concordance of histology and urea breath test. The sensitivity, specificity and positive and negative predictive values of each stool test were calculated. RESULTS: According to the reference method, the sensitivities of HpSA, Simple H. pyl and FemtoLab H. pylori immunoassays were 76%, 87% and 78%, respectively, and their specificities were 93%, 62% and 79%, respectively. CONCLUSIONS: Faecal tests are non-invasive and easy-to-perform tools for the diagnosis of H. pylori infection. However, their sensitivity and specificity seem to be non-optimal in patients with cirrhosis. 相似文献
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80.
Bilateral rupture of the patellar tendons is a rare lesion, usually associated with systemic diseases such as systemic lupus erythematosus, rheumatoid arthritis, chronic renal failure and others. It is extremely rare in a healthy individual, with fewer than 15 cases described. A case of a 32-year-old male with no known history of systemic disease or knee problems is presented. Physical examination, xrays and MRI demonstrated bilateral rupture of the patellar tendons. The tendons were repaired using a nonabsorbable suture reinforced with two titanium anchors fixed to each patella, and a quadriceps tendon flap. The evolution was satisfactory, with both knees recovering a full range of motion in a four-month period. 相似文献