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Comparar prospectivamente la tasa de detección de la PET/TC con 68Ga-DOTATATE versus 11C-colina en pacientes con cáncer de próstata en recaída bioquímica y evaluar in vivo la expresión de receptores de la somatostatina con el fin de planificar terapias dirigidas (177Lu-DOTATATE).

Evaluar la frecuencia de la captación focal de colon como observación incidental en estudios 18F-FDG PET/TC. Correlacionar dicho hallazgo con resultados histopatológicos.

Valorar las variantes fisiológicas, anatómicas y lesiones benignas en estudios por tomografía computada por emisión de positrones (PET/TC) con Galio 68 (68Ga)-DOTATATE.

We present the results of Thuan & Gunn rCCD imaging observations of the Universidad Complutense de Madrid (UCM) sample of emission–line galaxies (ELGs), selected by the presence of Hαemission in low–resolution objective prism spectra. In this work we characterize photometrically and morphologically a total of 212 objects from the UCM survey. This Paper presents the observations and basic reductions, and lists a set of photometric parameters calculated for each UCM object. In addition, for the first time in a ELGs sample, we have determined the morphological classification of the objects using simultaneously five different criteria.

Spectroscopic observations for the full sample of Hαemission–line galaxy candidates (ELGs) from the Universidad Complutense de Madrid objective-prism survey Lists 1 and 2 have been obtained in order to investigate fully the properties of the survey constituents as well as the selection characteristics and completeness limits of the survey itself. The spectroscopic data include redshifts, line fluxes, equivalent widths, emission-line ratios, optical reddening estimates and synthesized color indexes. We find that 74% of the objects in this sample do exhibit emission lines. We compare our observational data with parameters given in the published survey lists in order to assess the usefulness of the latter. The different emission-line galaxies have been classified according to their spectra in several groups. Gray-scale images of the CCD spectra near the main emission lines, spatial profiles at the continuum and the line for [OIII] λ5007 and Hαlines, as well as plots of the coadded spectra of selected galaxies are presented, and a number of peculiar objects are described.

We present the results of Thuan & Gunn rCCD imaging observations of the Universidad Complutense de Madrid (UCM) sample of emission-line galaxies (ELGs) selected by the presence of Hαemission in low resolution objective-prism spectra. In this work, a total of 212 objects from the UCM survey have been photometrically and morphologically characterized. In a previous paper, the observations, basic reductions and morphological classification for the UCM objects were presented. Here, we analyse the statistical properties of the sample and their interpretations. The main results obtained are as follows: (1) Our survey is specially effective in the detection of ELGs smaller and less luminous than normal spirals (the median values of the UCM sample are Mr= -20.6 and D24= 19.4 kpc, for H0= 50 km s-1Mpc-1). (2) The sample presents a very heterogeneous morphological population of galaxies. There is a clear predominance of late-type galaxies, with 66% being Sb or later. (3) We have found a set of galaxies specially interesting. In particular, we propose 9 candidates to BCD (blue compact dwarf galaxy), five of them previously unknown. (4) About 10% of the ELGs of the sample show typical parameters of S0 types, and in the subsample of 16 UCM interacting galaxies, 25% are S0 type galaxies. (5) In the set of UCM galaxies inside the Coma cluster, 71% exhibit Hubble types Sb or later.

Oligo(phenylimines) hereafter named PI6, PI8 and PI9 were synthesized by condensation reaction between the terephtalaldehyde and diamines of different length size (diaminohexane, diaminooctane and diaminononane) via mechanochemistry. The reactions were carried out without solvent or catalyst and completed after only 90 minutes. The products were characterized by 1H-NMR, UV-Vis, FT-IR spectroscopy, GPC, DSC and Small angle X-ray diffraction. Thin films were prepared by spin coating from concentrated solutions on glass and quartz substrates and mechanically rubbed with a polyacrylonitrile tissue. The oriented films were studied by both Laser Scanning Confocal Microscopy (LSCM) and UV-Vis spectroscopy. With this last technique, the higher optical dichroism was observed for PI6. The oriented films of this oligo(phenylimine) were thus used as patterns to induce molecular orientation of a fluorescent phenyleneethynylene polymer in order to obtain polarized light emission.

Resistance to doxorubicin based chemotherapy is a major therapeutic problem limiting advanced breast cancer treatment. 99mTc hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) has been reported to be extruded from tumour cells by the P-glycoprotein and multidrug resistance protein encoded by MDR1 and MRP1 genes, respectively. These proteins are involved in the cellular efflux of several chemotherapeutic agents including doxorubicin. The aim of this study was to investigate the clinical value of a standard 99mTc-MIBI scintimammography technique in the prediction of response to chemotherapy in advanced breast cancer patients. Fifty-six lesions from 33 female patients with locally advanced (n27) or recurrent breast cancer (n6) were included in the study. MIBI scintigraphy was performed 2-8 days prior to chemotherapy (FAC regimen). Images were acquired 10 min and 1 h post-injection of 740-1110 MBq of 99mTc-MIBI. Tumour-to-normal background tissue uptake ratios were calculated on each lesion in the early (TB(e)) and delayed phase of the study (TB(d)). Both TB(e) and TB(d) ratios were significantly higher (P<0.0001) in responders (n43) than nonresponders (n13). Diagnostic values of 99mTc-MIBI in the prediction of chemotherapy response were evaluated using the arbitrary cut-off values of 1.5 for TB(e) and 1.4 forTB(d). Sensitivity, specificity, positive and negative predictive values were 88.4, 92.3, 97.4, 70.6; and 90.7, 100.0, 100.0, 76.6, for TB(e) and TB(d), respectively. We conclude that 99mTc-MIBI scintigraphy may be a clinically valuable tool for guiding chemotherapy in advanced breast cancer patients.

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Diffusely reduced 99Tcm-pertechnetate uptake is a relatively infrequent but annoying finding that impairs evaluation of the thyroid gland. We studied 32 female patients aged 19–85 years with markedly reduced pertechnetate uptake. The following causes of reduced pertechnetate uptake were recognized: treatment with iodinated pharmaceuticals (n= 15), suppression therapy with T4 (n= 11), subacute thyroiditis (n= 5) and massive tumour replacement (n= 1). 99Tcm-MIBI thyroid scintigraphy was performed within 24 h of the pertechnetate study. The results were correlated with neck ultrasound, serum TSH (n= 25) and surgical findings in patients who had been operated on. The technique identified the following conditions: normally sized thyroids (n= 4), diffuse goitres (n= 8), multinodular goitres (n= 17) and solitary thyroid nodules (n= 3). Moreover, substernal goitres were identified in nine patients. This condition was confirmed at surgery in seven patients. Ultrasonography was concordant in 29 of 32 patients in terms of thyroid size and structure, but failed to demonstrate substernal thyroid tissue. Our results suggest that 99Tcm-MIBI scintigraphy may contribute to the diagnosis of thyroid pathology and treatment planning in patients with diffusely decreased 99Tcm-pertechnetate uptake.

This study documents the ultrastructural features of acute neuronal injury following N-methyl-d-aspartate (NMDA) receptor activation. NMDA (100 nmol/µl) or vehicle was infused over a 15-min period into the lateral ventricle of adult rats. After perfusion fixation, specimens demonstrating normal and abnormal patterns of vascular permeability to horserdish peroxidase were sampled for ultrastructural analysis. In NMDA-infused rats, brain regions exhibiting protein extravasation contained swollen dendritic profiles and abnormal neuronal perikarya. Although periventricular regions were most severely affected, parenchymal abnormalities were also detected in the cerebral cortex, septum, striatum, thalamus, hypothalamus and cerebellum. Mildly affected dendrites contained dark compact mitochondria, while in severely swollen dendrites mitochrondia were enlarged with ruptured cristae. Focal sites of plasma membrane disruption were also detected within swollen dendrites. Swollen neurons commonly displayed peripheral pallor and increased numbers of cytoplasmic vacuoles. Other neurons appeared dark and shrunken, some containing disrupted mitochrondria and pyknotic nuclei. Pretreatment with the NMDA antagonist MK-801 (2 mg/kg) attenuated the neuronal and dendritic alterations. In conditions where cerebrospinal fluid levels of glutamate are abnormally elevated, excessive NMDA receptor activation may lead to early vascular and neuronal complications which could work in concert to promote brain injury.

The purpose of this study was to document the early cerebrovascular consequences of excessive N-methyl-d-aspartate (NMDA) receptor activation. Five microliters of NMDA (100 nmol/µl) or vehicle was infused over a 15-min period into the lateral ventricle of adult rats. The protein tracer horseradisch peroxidase (HRP) was injected intravenously for blood-brain bartier (BBB) studies. The intraventricular infusion of vehicle (n=5) caused no alterations in arterial blood pressure or microvascular damage away from the intraventicular probe tract. In contrast, NMDA infusion (n=8) led to a gradual increase in arterial blood pressure (mean 36 mm Hg). Multifocal regions of HRP extravasation were observed bilaterally throughout the neuraxis following NMDA infusion. Sites of BBB disruption and hemorrhage included brain regions bordering ventricular spaces. In addition, isolated foci of protein extravasation were commonly detected in the cerebral cortex, thalamus, basal forebrain, septum and cerebellum. Pretreatment with the noncompetitive NMDA antagonist MK-801 (2 mg/kg) substantially reduced the BBB responses to NMDA. However, microvascular abnormalities were seen in NMDA-infused rats where blood pressure elevations were inhibited by blood removal. In addition to neurons, cerebral blood vessels are also acutely affected by NMDA receptor activation. Blockage of NMDA receptor channels following brain injury may potentially provide protection by attenuating BBB breakdown and subsequent brain edema.

An experimental study on the thermal expansion of a collection of crosslinked low-density polyethylene (LDPE) foams with closed-cell structure is presented. The thermal characterization of these materials, the relationships between the linear thermal expansion coefficient and the structure of the foams, and the determination of the variables that can modify the thermal properties of these products are the goals of this work. The experimental results show that the linear thermal expansion coefficient decreases when the density of the foamed material increases. The gas expansion inside the cells is a mechanism that should be taken into account. Moreover, the thermal expansion also depends on the cellular structure. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. B Polym. Phys. 36: 2587–2596, 1998

A comparative study of pepsitensin and hypertensin agree in repect to all their known chemical and pharmacological characteristics. We wish to thank Professor B. Houssay for his kindness in providing us with part of the hypertensin used in these experiments, and to thank Professor E. Cruz Coke for his gift of Northrop pepsin.

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