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We have used protein cross-linking with the zero-length cross-linker 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, and radiolytic footprinting coupled with high-resolution tandem mass spectrometry, to examine the structure of higher-plant PsbO when it is bound to Photosystem II. Twenty intramolecular cross-linked residue pairs were identified. On the basis of this cross-linking data, spinach PsbO was modeled using the Thermosynechococcus vulcanusPsbO structure as a template, with the cross-linking distance constraints incorporated using the MODELLER program. Our model of higher-plant PsbO identifies several differences between the spinach and cyanobacterial proteins. The N-terminal region is particularly interesting, as this region has been suggested to be important for oxygen evolution and for the specific binding of PsbO to Photosystem II. Additionally, using radiolytic mapping, we have identified regions on spinach PsbO that are shielded from the bulk solvent. These domains may represent regions on PsbO that interact with other components, as yet unidentified, of the photosystem.

El cáncer de endometrio es el cáncer ginecológico pélvico más frecuente en Francia, con 6.800 casos anuales. En la mayoría de las ocasiones, se produce después de la menopausia y, por lo general, se diagnostica en un estadio precoz debido a una semiología muy llamativa: las metrorragias posmenopáusicas, por lo que es un cáncer de buen pronóstico. Los principales factores de riesgo son la obesidad, la diabetes y la exposición prolongada a los estrógenos. Existen formas de cáncer de endometrio que aparecen en pacientes más jóvenes y que requieren la búsqueda de un síndrome de cáncer colorrectal no polipósico hereditario (síndrome de Lynch). Se han definido dos tipos histológicos de cánceres del endometrio: el tipo 1 (tumores endometrioides) y el tipo 2 (que incluye los carcinomas de células claras, los carcinomas papilares serosos y los carcinosarcomas). Su tratamiento y su pronóstico difieren, tal y como se recoge en las nuevas recomendaciones del Institut National du Cancer francés de 2010. El reto terapéutico consiste en no tratar en exceso las formas de buen pronóstico, para reducir la morbilidad, pero sin subtratar las formas de pronóstico menos bueno. Cualquier metrorragia posmenopáusica debe evaluarse mediante un frotis cervicovaginal, una ecografía pélvica y una biopsia del endometrio. El estudio preterapéutico de un cáncer diagnosticado consiste en la realización sistemática de una resonancia magnética abdominopélvica con apreciación del grado de infiltración del miometrio y exploración de las áreas ganglionares. El tratamiento consiste en cirugía (salvo en los estadios tardíos), dando prioridad a la vía laparoscópica, y en radioterapia externa. La realización de linfadenectomías no es sistemática, sobre todo en los tumores limitados al cuerpo uterino con bajo riesgo de recidiva. El seguimiento se basa exclusivamente en la clínica.

OBJECTIVES: The present study aimed at the analysis of release patterns of neurobiochemical markers of brain damage (neuron specific enolase (NSE) and protein S-100B) in patients with traumatic brain injury and their predictive value with respect to the short and long term neuropsychological outcome. METHODS: Serial NSE and S-100B concentrations were analysed in blood samples taken at the first, second, and third day after traumatic brain injury. In 69 patients who fulfilled the inclusion criteria (no history of neurological or psychiatric disorder or alcohol or drug dependency, blood sampling according to the scheduled time scale, aged between 16 and 65 years) standardised neurological examinations and qualitative and quantitative evaluation of CT were performed. Comprehensive neuropsychological assessment was performed in 39 subjects 2 weeks after admission and in 29 subjects at a 6 month follow up examination. RESULTS: Most patients presented with minor head injuries (GCS13) at the time of admission. Six months later most patients were fully independent in activities of daily living. Two thirds of the patients, however, still had neuropsychological dysfunction. Patients with short and long term neuropsychological disorders had significantly higher NSE and S-100B serum concentrations and a significantly longer lasting release of both markers. A comparative analysis of the predictive value of clinical, neuroradiological, and biochemical data showed initial S-100B values above 140 ng/l to have the highest predictive power. CONCLUSIONS: The analysis of post-traumatic release patterns of neurobiochemical markers of brain damage might help to identify patients with traumatic brain injury who run a risk of long term neuropsychological dysfunction.

AbstractThe diffusion of molecules sorbed in zeolites is of growing interest for understanding the mechanisms of chemical processes with regard to selectivity and reactivity [1].MD simulations give insight into physical systems on the molecular level allowing to study and visualize the motion of molecules even beyond the possibilities of experiments [2,3]. Single system parameters can easily be varied to study their influence, also those parameters that are fixed in reality (e.g., the size of particles). We present a cross section of our recent work to illustrate the capabilities of MD: The self diffusion coefficients (D) of a mixture of methane and xenon in silicalite show remarkable deviations from those of the pure species. This is shown and confirmed by PFG NMR experiments [4].Simulating ethane in zeolite A the mechanism of diffusion has been studied. The effects of rotation on the diffusion lead to cases where Ddecreases with growing temperature [5].The independence of self diffusion on lattice vibrations is proven even for zeolites with windows of guest particle size comparing simulations with rigid and vibrating zeolite lattice [6].

425 patients showing mild coronary artery disease (CAD) on arteriography were enrolled in a multicentre trial and randomised to treatment with nifedipine (80 mg/day) or placebo. The two groups were well matched for age, sex, and risk factors. 348 patients (82%) underwent repeat arteriography 3 years later; 282 (134 nifedipine, 148 placebo) had received treatment throughout, but treatment had been stopped in 39 nifedipine-treated and 27 placebo-treated patients after average periods of 354 and 467 days. Computer-assisted measurements of arteriograms from all restudied patients (175 placebo, 173 nifedipine) showed no significant differences in the number or severity of lesions on initial arteriograms, or in the progression or regression of existing lesions over 3 years. In contrast, the number of new lesions per patient was significantly lower in the nifedipine group than in the placebo group (0·59 vs 0·82 lesions per patient, a 28% reduction). Thus in patients with mild CAD nifedipine substantially suppresses disease progression as shown by the appearance of new lesions detectable by quantitative coronary arteriography.

The recent introduction of IC technologies offering high frequency transistors withftgreater than 10 GHz has opened new opportunities for higher integration of wireless communication systems. Fast silicon IC devices make possible the integration of many RF subsystems on a single die and offer a total solution to mixed frequency (low frequency and RF) and mixed signal (analog and digital) systems. This paper describes IC implementation challenges of a 2.4 GHz wireless LAN chipset developed at Harris Semiconductor.

Animal experiments suggest an inhibitory effect of calcium entry blockers on arterial calcinosis and the formation of atherosclerotic plaques. Experiments with isolated tissues suggest various mechanisms for an antiatherosclerotic effect of calcium entry blockers.

A new procedure to test and evaluate imaging properties of liquid crystal optical transducers is described. The method involves the observation of temporal histories of image-related Fourier spatial frequency signals and is demonstrated for a grating input. Results show that information on timing of spectrum events can be used to modify coherent light imagery. A comparison of spectral features for two liquid crystal transducer types is given.

This paper is the third of a three-part sequence. A modified Fourier spectrum analyzer system that uses an optical transducer to contain cell images is described. The photoconductor – liquid crystal transducer modulates a transmitted laser beam producing a high contrast cell image. The transducer is operated in a light scattering mode to achieve a contrast ratio in excess of 1000:1 and a gamma of about 10. Cell discriminant features are obtained from the transform spectrum of the transducer modulated image. The ability to classify cells from feature measurements is comparable with previous cell-by-cell classification performance based on cell photography.

The diffusion of a mixture of methane and xenon in the zeolite silicalite is studied by use of molecular dynamics (MD) simulations and pulsed field gradient (PFG) nuclear magnetic resonance (NMR). For a fixed total number of guest molecules, the ratio of xenon to methane is varied in order to examine the special properties of diffusion in a mixture. High xenon concentrations were found to slow the methane diffusivity in the mixture, while the diffusion of xenon is nearly unaffected by high methane concentrations. The reason for the dominance of xenon is the larger local heat of adsorption of xenon and the larger mass of xenon compared to methane in combination with channel size and topology in silicalite. Simulated and experimental data are in very good agreement with each other. Diffusion anisotropy as resulting from the MD simulations is discussed in terms of the correlation rule for diffusion in the interconnected pore system of ZSM-5 (Kärger, J. J. Phys. Chem. 1991, 98, 5558).

The structure factors of the amorphous, icosahedral and crystalline Pd58.8U20.6Si20.6 were measured with X-rays and neutrons. By comparing the radial distribution functions of the three phases, we find a similar short range order in the amorphous and icosahedral phase, but a different atomic arrangement in the crystalline phase. A magnetic long range order observed in the crystalline material is absent in the icosahedral phase.

No abstract.

Most of patients suffering from resistant hypertension (HTN) have obstructive sleep apnea (OSA). Little data are available to confirm or not the efficacy of continuous positive airway pressure (CPAP) on blood pressure (BP) in resistant HTN.