Total orthotopic small bowel transplantation in swine under FK 506

Previous experimental studies in rodents and in dogs have established the efficacy of FK 506 in controlling the immunologic events following small bowel or multivisceral transplantation.1–5 To complete the assessment of FK 506 in experimental small bowel transplantation, we present here our experience with the frequently used swine model

Nonlinear quantum model for atomic Josephson junctions with one and two bosonic species

We study atomic Josephson junctions (AJJs) with one and two bosonic species confined by a double-well potential. Proceeding from the second quantized Hamiltonian, we show that it is possible to describe the zero-temperature AJJs microscopic dynamics by means of extended Bose-Hubbard (EBH) models, which include usually-neglected nonlinear terms. Within the mean-field approximation, the Heisenberg equations derived from such two-mode models provide a description of AJJs macroscopic dynamics in terms of ordinary differential equations (ODEs). We discuss the possibility to distinguish the Rabi, Josephson, and Fock regimes, in terms of the macroscopic parameters which appear in the EBH Hamiltonians and, then, in the ODEs. We compare the predictions for the relative populations of the Bose gases atoms in the two wells obtained from the numerical solutions of the two-mode ODEs, with those deriving from the direct numerical integration of the Gross-Pitaevskii equations (GPEs). Our investigations shows that the nonlinear terms of the ODEs are crucial to achieve a good agreement between ODEs and GPEs approaches, and in particular to give quantitative predictions of the self-trapping regime.Comment: Accepted for the publication in J. Phys. B: At. Mol. Opt. Phy

Quantum diffusion with disorder, noise and interaction

Disorder, noise and interaction play a crucial role in the transport properties of real systems, but they are typically hard to control and study both theoretically and experimentally, especially in the quantum case. Here we explore a paradigmatic problem, the diffusion of a wavepacket, by employing ultra-cold atoms in a disordered lattice with controlled noise and tunable interaction. The presence of disorder leads to Anderson localization, while both interaction and noise tend to suppress localization and restore transport, although with completely different mechanisms. When only noise or interaction are present we observe a diffusion dynamics that can be explained by existing microscopic models. When noise and interaction are combined, we observe instead a complex anomalous diffusion. By combining experimental measurements with numerical simulations, we show that such anomalous behavior can be modeled with a generalized diffusion equation, in which the noise- and interaction-induced diffusions enter in an additive manner. Our study reveals also a more complex interplay between the two diffusion mechanisms in regimes of strong interaction or narrowband noise.Comment: 11 pages, 10 figure

2,4-Dichloro-1-[1-(2,4-dichloro­benz­yl­oxy)eth­yl]benzene

In the title compound, C15H12Cl4O, the dihedral angle between the least-squares planes of the two benzene rings is 82.6 (9)°. The dihedral angles between the COC mean plane of the ­oxy group and the two benzene rings are 84.3 (5) and 10.8 (5)°. In the crystal, two weak π–π inter­actions [centroid–centroid distances = 3.9989 (8) and 3.7912 (8) Å] and a C—H⋯π inter­action are observed

Localization from quantum interference in one-dimensional disordered potentials

We show that the tails of the asymptotic density distribution of a quantum wave packet that localizes in the the presence of random or quasiperiodic disorder can be described by the diagonal term of the projection over the eingenstates of the disordered potential. This is equivalent of assuming a phase randomization of the off-diagonal/interference terms. We demonstrate these results through numerical calculations of the dynamics of ultracold atoms in the one-dimensional speckle and quasiperiodic potentials used in the recent experiments that lead to the observation of Anderson localization for matter waves [Billy et al., Nature 453, 891 (2008); Roati et al., Nature 453, 895 (2008)]. For the quasiperiodic case, we also discuss the implications of using continuos or discrete models.Comment: 5 pages, 3 figures; minor changes, references update

Distribution of different isoforms of receptor protein tyrosine phosphatase \u3b3 (Ptprg-RPTP \u3b3) in adult mouse brain: upregulation during neuroinflammation.

The receptor protein tyrosine phosphatase \u3b3 (Ptprg-RPTP\u3b3) is a receptor protein widely expressed in many tissues, including the central nervous system (CNS). Several RPTP\u3b3 isoforms are expressed in the brain during development and in adulthood, but their distribution and role are unknown. In this study, we investigated the distribution of some RPTP\u3b3 isoforms in the adult brain using antibodies against the epitopes localized in the C- and in the N-terminal domains of the full length isoform of RPTP\u3b3. We found a predominant and widespread neuronal positivity throughout the neocortex, hippocampus, striatum and in many nuclei of the brainstem and cerebellum. At least 2 distinct isoforms that can co-exist in various compartments in the same cell are detectable in different neuron types. Immunopositivity for epitopes located in both the N- and C-terminus domains were found in the neuropil of cortical and hippocampal neurons, whereas the N-terminal domain positivity was found in the soma, often without colocalization with its C-terminal counterpart. Among glial cells, some protoplasmic and perivascular astrocytes and the cerebellar Bergmann glia, express RPTP\u3b3. The astrocytic expression of RPTP\u3b3 and putative processing isoforms of 120 and 80 kDa increases during neuroinflammation, in particular 24 h after LPS treatment. Activated astrocytes were found to be strongly positive for RPTP\u3b3 also in a mice model of Alzheimer's disease. Our results confirm previous findings and enrich the current knowledge of RPTP\u3b3 distribution in the CNS, highlighting a role of RPTP\u3b3 during neuroinflammation processes

Imaging cortical activity following affective stimulation with a high temporal and spatial resolution

Keil J, Adenauer H, Catani C, Neuner F. Imaging cortical activity following affective stimulation with a high temporal and spatial resolution. BMC Neuroscience. 2009;10(1):83.Background:The affective and motivational relevance of a stimulus has a distinct impact on cortical processing, particularly in sensory areas. However, the spatial and temporal dynamics of this affective modulation of brain activities remains unclear. The purpose of the present study was the development of a paradigm to investigate the affective modulation of cortical networks with a high temporal and spatial resolution. We assessed cortical activity with MEG using a visual steady-state paradigm with affective pictures. A combination of a complex demodulation procedure with a minimum norm estimation was applied to assess the temporal variation of the topography of cortical activity. Results: Statistical permutation analyses of the results of the complex demodulation procedure revealed increased steady-state visual evoked field amplitudes over occipital areas following presentation of affective pictures compared to neutral pictures. This differentiation shifted in the time course from occipital regions to parietal and temporal regions. Conclusion: It can be shown that stimulation with affective pictures leads to an enhanced activity in occipital region as compared to neutral pictures. However, the focus of differentiation is not stable over time but shifts into temporal and parietal regions within four seconds of stimulation. Thus, it can be crucial to carefully choose regions of interests and time intervals when analyzing the affective modulation of cortical activity

Rapid recognition of drug-resistance/sensitivity in leukemic cells by Fourier transform infrared microspectroscopy and unsupervised hierarchical cluster analysis.

We tested the ability of Fourier Transform (FT) InfraRed (IR) microspectroscopy (microFTIR) in combination with unsupervised Hierarchical Cluster Analysis (HCA) in identifying drug-resistance/sensitivity in leukemic cells exposed to tyrosine kinase inhibitors (TKIs). Experiments were carried out in a well-established mouse model of human Chronic Myelogenous Leukemia (CML). Mouse-derived pro-B Ba/F3 cells transfected with and stably expressing the human p210(BCR-ABL) drug-sensitive wild-type BCR-ABL or the V299L or T315I p210(BCR-ABL) drug-resistant BCR-ABL mutants were exposed to imatinib-mesylate (IMA) or dasatinib (DAS). MicroFTIR was carried out at the Diamond IR beamline MIRIAM where the mid-IR absorbance spectra of individual Ba/F3 cells were acquired using the high brilliance IR synchrotron radiation (SR) via aperture of 15 7 15 \u3bcm(2) in sizes. A conventional IR source (globar) was used to compare average spectra over 15 cells or more. IR signatures of drug actions were identified by supervised analyses in the spectra of TKI-sensitive cells. Unsupervised HCA applied to selected intervals of wavenumber allowed us to classify the IR patterns of viable (drug-resistant) and apoptotic (drug-sensitive) cells with an accuracy of >95%. The results from microFTIR + HCA analysis were cross-validated with those obtained via immunochemical methods, i.e. immunoblotting and flow cytometry (FC) that resulted directly and significantly correlated. We conclude that this combined microFTIR + HCA method potentially represents a rapid, convenient and robust screening approach to study the impact of drugs in leukemic cells as well as in peripheral blasts from patients in clinical trials with new anti-leukemic drugs

Inapplicability of advance directives in a paternalistic setting: the case of a post-communist health system

<p>Abstract</p> <p>Background</p> <p>The Albanian medical system and Albanian health legislation have adopted a paternalistic position with regard to individual decision making. This reflects the practices of a not-so-remote past when state-run facilities and a totalitarian philosophy of medical care were politically imposed. Because of this history, advance directives concerning treatment refusal and do-not-resuscitate decisions are still extremely uncommon in Albania. Medical teams cannot abstain from intervening even when the patient explicitly and repeatedly solicits therapeutic abstinence. The Albanian law on health care has no provisions regarding limits or withdrawal of treatment. This restricts the individual's healthcare choices.</p> <p>Discussion</p> <p>The question of <it>'medically futile' </it>interventions and pointless life-prolonging treatment has been discussed by several authors. Dutch physicians call such interventions '<it>medisch zinloos</it>' (<it>senseless</it>), and the Netherlands, as one of the first states to legislate on end-of-life situations, actually regulates such issues through appropriate laws. In contrast, leaving an 'advance directive' is not a viable option for Albanian ailing individuals of advanced age. Verbal requests are provided during periods of mental competence, but unfortunately such instructions are rarely taken seriously, and none of them has ever been upheld in a legal or other official forum.</p> <p>Summary</p> <p>End-of-life decisions, treatment refusal and do-not-resuscitate policies are hazardous options in Albania, from the legal point of view. Complying with them involves significant risk on the part of the physician. Culturally, the application of such instructions is influenced from a mixture of religious beliefs, death coping-behaviors and an immense confusion concerning the role of proxies as decision-makers. Nevertheless, Albanian tradition is familiar with the notion of '<it>amanet</it>', a sort of living will that mainly deals the property and inheritance issues. Such living wills, verbally transmitted, may in certain cases include advance directives regarding end-of-life decisions of the patient including refusal or termination of futile medical treatments. Since these living wills are never formally and legally validated, their application is impossible and treatment refusal remains still non practicable. Tricks to avoid institutional treatment under desperate conditions are used, aiming to provide legal coverage for medical teams and relatives that in extreme situations comply with the advice of withholding senseless treatment.</p