18,817 research outputs found
Miglioramento della sopravvivenza di lembi cutanei e muscolocutanei ischemici attraverso il trasferimento del gene vegf165 mediante vettori virali adeno-associati (AAV)
The sim gene of Escherichia coli phage P1: nucleotide sequence and purification of the processed protein
Maillou J, Dreiseikelmann B. The sim gene of Escherichia coli phage P1: nucleotide sequence and purification of the processed protein. Virology. 1990;175(2):500-507.The sim gene of bacteriophage P1 causes exclusion of a superinfecting P1 phage. We determined the nucleotide sequence of a 1.9-kb DNA fragment that, in plasmids, causes Sim phenotype. There are two open reading frames within this region for proteins of 82 and 259 amino acids. A 1.3-kb fragment containing the larger open reading frame was inserted into an expression vector. Induced cells carrying the hybrid plasmid, termed pBD5, were not infected by phage P1 and produced a 24-kDa protein and, to a smaller extent, a 25-kDa protein. The 24-kDa protein was purified. Comparison of its amino-terminal amino acid sequence with the nucleotide sequence indicated that it is processed from a precursor protein by removal of a hydrophobic leader peptide of 20 amino acids. In vivo processing depends on secA gene function and is necessary for Sim interference with P1 infection. The data are discussed with respect to the function of the sim gene in superinfection exclusion
EFFETTI DEL TRASFERIMENTO INTRAMUSCOLARE DEL GENE VEGF165 MEDIANTE VETTORI VIRALI ADENO-ASSOCIATI (AAV) SU LEMBI ADDOMINALI PERFORANTI DEL RATTO
Sensititre Y05 per l’antimicogramma di lieviti e muffe
Il pannello Sensititre YO5, non ancora disponibile per antimicogrammi di routine, comprende la caspofungina, un’echinocandina con ampio spettro d’azione che inibisce specificamente la ß1-3 D-glucan sintetasi e danneggia direttamente l’impalcatura della parete cellulare.
Il pannello è stato utilizzato per l’antimicogramma di 128 ceppi clinici di funghi di cui 16 Aspergillus spp. e 112 Candida spp. Come ceppi di controllo sono stati utilizzati C. krusei ATCC® 6258, C. parapsilosis ATCC® 22019 e A. flavus ATCC® 204304
Coulomb blockade and Kondo effect in a quantum hall antidot
We propose a general capacitive model for an antidot, which has two localized edge states with different spins in the quantum Hall regime. The capacitive coupling of localized excess charges, which are generated around the antidot due to magnetic flux quantization, and their effective spin fluctuation can result in Coulomb blockade, h/(2e) Aharonov-Bohm oscillations, and the Kondo effect. The resultant conductance is in qualitative agreement with recent experimental data.H. S. S. and M. K. thank C. J. B. Ford and H. Schomerus
for helpful discussions. The discussions with K. Kikoin,
K. Kang, and T. S. Kim are acknowledged.We were supported
by SKORE-A(HY and MSC), eSSC (MSC), and
QSRC at Dongguk University (SREY)
Polarization spectral synthesis for Type Ia supernova explosion models
We present a Monte Carlo radiative transfer technique for calculating synthetic spectropolarimetry for multidimensional supernova explosion models. The approach utilizes 'virtual-packets' that are generated during the propagation of the Monte Carlo quanta and used to compute synthetic observables for specific observer orientations. Compared to extracting synthetic observables by direct binning of emergent Monte Carlo quanta, this virtual-packet approach leads to a substantial reduction in the Monte Carlo noise. This is not only vital for calculating synthetic spectropolarimetry (since the degree of polarization is typically very small) but also useful for calculations of light curves and spectra. We first validate our approach via application of an idealized test code to simple geometries. We then describe its implementation in the Monte Carlo radiative transfer code ARTIS and present test calculations for simple models for Type Ia supernovae. Specifically, we use the well-known one-dimensional W7 model to verify that our scheme can accurately recover zero polarization from a spherical model, and to demonstrate the reduction in Monte Carlo noise compared to a simple packet-binning approach. To investigate the impact of aspherical ejecta on the polarization spectra, we then use ARTIS to calculate synthetic observables for prolate and oblate ellipsoidal models with Type Ia supernova compositions.</p
A simple disc wind model for broad absorption line quasars
Approximately 20 per cent of quasi-stellar objects (QSOs) exhibit broad, blue-shifted absorption lines in their ultraviolet spectra. Such features provide clear evidence for significant outflows from these systems, most likely in the form of accretion disc winds. These winds may represent the ‘quasar’ mode of feedback that is often invoked in galaxy formation/evolution models, and they are also key to unification scenarios for active galactic nuclei (AGN) and QSOs. To test these ideas, we construct a simple benchmark model of an equatorial, biconical accretion disc wind in a QSO and use a Monte Carlo ionization/radiative transfer code to calculate the ultraviolet spectra as a function of viewing angle. We find that for plausible outflow parameters, sightlines looking directly into the wind cone do produce broad, blue-shifted absorption features in the transitions typically seen in broad absorption line (BAL) QSOs. However, our benchmark model is intrinsically X-ray weak in order to prevent overionization of the outflow, and the wind does not yet produce collisionally excited line emission at the level observed in non-BAL QSOs. As a first step towards addressing these shortcomings, we discuss the sensitivity of our results to changes in the assumed X-ray luminosity and mass-loss rate, Ṁwind. In the context of our adopted geometry, Ṁwind ∼ Ṁacc is required in order to produce significant BAL features. The kinetic luminosity and momentum carried by such outflows would be sufficient to provide significant feedback
Effects of intracerebroventricular administration of beta-funaltrexamine on DAMGO-stimulated [35S]GTP-gamma-S binding in rat brain sections
Intracerebroventricular administration of beta-funaltrexamine (beta-FNA) reduces the density of mu opioid receptors as measured by in situ autoradiography by 40-50% throughout the brain, with little regional variation [Martin et al. (1993) J. Pharmacol. Exp. Ther. 267:506-514] Recently an assay has been developed to study opioid stimulation of [35S]GTP-gamma-S binding autoradiographically in situ using slide-mounted brain sections [Sim et al. (1995) Proc. Natl. Acad. Sci. U.S.A. 92:7242-7246]. The present study was undertaken to determine the effect of mu opioid receptor alkylation on G protein activation by the mu opioid agonist DAMGO. Animals were injected intracerebroventricularly with 40 nmol of beta-FNA or saline and sacrificed 24 hours later. DAMGO stimulated [35S]GTP-gamma-S binding with an anatomical specificity consistent with the localization of mu opioid receptors. The percent stimulation by DAMGO ranged from approximately 50 to 100% in the regions studied. beta-FNA significantly decreased G protein activation by DAMGO in regions that are consistent with its reported long-lasting and insurmountable antagonism of the antinociceptive (medial thalamus, central gray) and reinforcing (nucleus accumbens) effects of mu opioid agonists [Adams et al. (1990) J. Pharmacol. Exp. Ther. 255:1027-1032; Martin et al. (1995) J. Pharmacol. Exp. Ther. 272:1135-1140]. However, the effects of beta-FNA were not equal in all brain regions. This may indicate regional differences in the coupling efficiency of mu opioid receptors with G proteins, or in the effects of beta-FNA on mu opioid receptor binding or on mu opioid receptor-stimulated G protein activity
Retention of data in heat-damaged SIM cards and potential recovery methods
Examination of various SIM cards and smart card devices indicates that data may be retained in SIM card memory structures even after heating to temperatures up to 450oC, which the National Institute of Standards and Technology (NIST) has determined to be approximately the maximum average sustained temperature at desk height in a house fire. However, in many cases, and certainly for temperatures greater than 450oC, the SIM card chip has suffered structural or mechanical damage that renders simple probing or rewiring ineffective. Nevertheless, this has not necessarily affected the data, which is stored as charge in floating gates, and alternative methods for directly accessing the stored charge may be applicable
Utilizzazione della PCR per la diagnosi di zigomicosi
Le zigomicosi sono infezioni fungine invasive gravi ad evoluzione fatale nell’ospite immunocompromesso.
La diagnosi convenzionale è resa spesso difficoltosa dall’impossibilità di ottenere prelievi o campioni bioptici significativi. La diagnosi molecolare potrebbe rappresentare una valida alternativa.
Recentemente, ci è stato richiesto di accertare in preparati istologici (vetrini non colorati) la presenza di DNA appartenente a zigomiceti, il cui parassitismo tessutale era stato riscontrato utilizzando colorazioni istologiche specifiche per i fungh
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