Sapienza University of Rome

About: Sapienza University of Rome is a education organization based out in Rome, Lazio, Italy. It is known for research contribution in the topics: Population & Medicine. The organization has 62002 authors who have published 155468 publications receiving 4397244 citations. The organization is also known as: La Sapienza & Università La Sapienza di Roma.

Amino acid composition and sequence of dermorphin, a novel opiate‐like peptide from the skin of phyllomedusa sauvagei

Abstract: Dermorphin, a heptapeptide with very potent opiate-like activity, has been isolated from methanol extracts of the skin of the South American frog Phyllomedusa sauvagei. The amino acid sequence of the peptide is: H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2. Dermorphin presents striking differences from the known enkephalins; it offers a surprising example of a peptide from Vertebrata containing a D-amino acid residue in its sequence.

Report of the European Myeloma Network on multiparametric flow cytometry in multiple myeloma and related disorders

Abstract: The European Myeloma Network (EMN) organized two flow cytometry workshops. The first aimed to identify specific indications for flow cytometry in patients with monoclonal gammopathies, and consensus technical approaches through a questionnaire-based review of current practice in participating laboratories. The second aimed to resolve outstanding technical issues and develop a consensus approach to analysis of plasma cells. The primary clinical applications identified were: differential diagnosis of neoplastic plasma cell disorders from reactive plasmacytosis; identifying risk of progression in patients with MGUS and detecting minimal residual disease. A range of technical recommendations were identified, including: 1) CD38, CD138 and CD45 should all be included in at least one tube for plasma cell identification and enumeration. The primary gate should be based on CD38 vs. CD138 expression; 2) after treatment, clonality assessment is only likely to be informative when combined with immunophenotype to detect abnormal cells. Flow cytometry is suitable for demonstrating a stringent complete remission; 3) for detection of abnormal plasma cells, a minimal panel should include CD19 and CD56. A preferred panel would also include CD20, CD117, CD28 and CD27; 4) discrepancies between the percentage of plasma cells detected by flow cytometry and morphology are primarily related to sample quality and it is, therefore, important to determine that marrow elements are present in follow-up samples, particularly normal plasma cells in MRD negative cases.

A High‐Performance Polymer Tin Sulfur Lithium Ion Battery

Abstract: The lithium–sulfur battery, based on the electrochemical reaction 16 Li + S8Q8Li2S, has a theoretical specific energy and energy density of 2500 Wh kg 1 and 2800 WhL , respectively, much greater than those of any conventional lithium battery. The Li–S battery has been investigated by many workers for several decades; however, such studies have been limited to the simplest cell configuration consisting of sulfur as the positive electrode, lithium metal as the negative electrode, and a solution of a lithium salt in an aprotic organic solvent as the electrolyte. The practical development of the lithium–sulfur battery has been hindered to date by a series of shortcomings. A major hurdle is the high solubility in the organic electrolyte of the polysulfides Li2Sx (1 x 8) that form as intermediates during both charge and discharge processes. This high solubility results in a loss of active mass, which is reflected in a low utilization of the sulfur cathode and in a severe capacity decay upon cycling. The dissolved polysulfide anions, by migration through the electrolyte, may reach the lithium metal anode, where they react to form insoluble products on its surface; this process also negatively impacts the battery operation. Various strategies to address the solubility issue have been explored. They include the design of modified organic liquid electrolytes and the use of ionic-liquidbased electrolytes and polymer electrolytes. However, although interesting, the results are still far from marking real breakthroughs in the field. Important progress was recently made by Nazar and coworkers, who showed that by fabricating cathodes based on an intimate mixture of nanostructured sulfur and mesoporous carbon, high reversible capacity and good rates can be obtained. However, this battery is also based on conventional chemistry in terms of anode and electrolyte, as it contains a lithium metal foil anode and an organic liquid electrolyte. Lithium metal is very reactive in common lithium battery electrolyte media: the organic solution readily decomposes at the metal surface, thus forming a passivating layer. Nonuniformities in this layer result in dendrite deposition that may eventually extend to short the cell, with negative repercussion for the cycle life of the battery and also for its safety. For this reason, commercial “lithium” batteries do not use a lithium metal anode but rather a material capable of hosting and releasing lithium ions (e.g., graphite) in order to operate by lithium ion transfer only, thus carefully avoiding any lithium metal deposition. It is then surprising that all the strategies attempted to date to achieve progress with the Li–S battery have been concentrated on the cathode problems, totally neglecting those associated with the anode. The key challenge is then to totally renew the chemistry of this battery such as to achieve an advanced configuration that can consistently provide high capacity, a long cycle life, and safe operation. Herein, we report an example of a lithiummetal-free new battery version and demonstrate that, to a large extent, it can effectively meet these targets. In contrast to most of the Li–S batteries proposed to date, which are fabricated in the “charged” state, that is, using a carbon–sulfur composite cathode that necessarily requires a lithium metal counter electrode (anode) to assure the 16 Li + S8!8Li2S discharge process, we propose to fabricate the battery in the “discharged” state by using a carbon lithium sulfide composite as the cathode. The battery may be activated by reversing the above process, that is, by converting lithium sulfide back to lithium and sulfur (8Li2S!16 Li + S8). We show herein that the charging process may be reversibly turned into a reverse discharge process and that the entire charge–discharge cycle can be efficiently repeated several times. We also renewed the electrolyte component by replacing the common liquid organic solutions with a gel-type polymer membrane, formed by trapping an ethylene carbonate /dimethylcarbonate lithium hexafluorophosphate (EC:DMC LiPF6) solution saturated with lithium sulfide in a polyethylene oxide / lithium trifluoromethanesulfonate (PEO/ LiCF3SO3) polymer matrix. [15] A dispersed zirconia ceramic filler enhances the mechanical properties of the gel and improves liquid retention within its bulk. For simplicity, we refer to this composite gel polymer electrolyte as CGPE. The photograph in Figure 1a demonstrates the plastic appearance of the CGPE polymer electrolyte. We can describe this electrolyte as a membrane with liquid zones contained within a polymer envelope. It is expected that when the membrane is used as electrolyte in the cell, the external polymer layer may act as a physical barrier preventing the direct contact of the electrode components with the internal liquid solution. This barrier function will help to control the dissolution of the sulfide anions from the cathode and to prevent the attack of the same anions at the anode. Bearing in mind that the solubility of the sulfide anions is one of the key factors affecting cell life and performance, we have further enforced its control by supplementing the electrolyte with lithium sulfide up to saturation, which leads to a combined physical and chemical barrier to block most the dissolution. [*] Dr. J. Hassoun, Prof. B. Scrosati Dipartimento di Chimica Universit degli Studi di Roma La Sapienza Piazzale Aldo Moro, 5, 00185 Roma (Italy) Fax: (+ 39)06-491-769 E-mail: bruno.scrosati@uniroma1.it

Groups as epistemic providers: need for closure and the unfolding of group-centrism.

Abstract: Theory and research are presented relating the need for cognitive closure to major facets of group behavior. It is suggested that a high need for closure, whether it is based on members' disposition or the situation, contributes to the emergence of a behavioral syndrome describable as group-centrism--a pattern that includes pressures to opinion uniformity, encouragement of autocratic leadership, in-group favoritism, rejection of deviates, resistance to change, conservatism, and the perpetuation of group norms. These theoretical predictions are borne out by laboratory and field research in diverse settings.

Multiple Distinct Sets of Stereotyped Antigen Receptors Indicate a Role for Antigen in Promoting Chronic Lymphocytic Leukemia

Abstract: Previous studies suggest that the diversity of the expressed variable (V) region repertoire of the immunoglobulin (Ig)H chain of B-CLL cells is restricted. Although limited examples of marked constraint in the primary structure of the H and L chain V regions exist, the possibility that this level of restriction is a general principle in this disease has not been accepted. This report describes five sets of patients, mostly with unmutated or minimally mutated IgV genes, with strikingly similar B cell antigen receptors (BCRs) arising from the use of common H and L chain V region gene segments that share CDR3 structural features such as length, amino acid composition, and unique amino acid residues at recombination junctions. Thus, a much more striking degree of structural restriction of the entire BCR and a much higher frequency of receptor sharing exists among patients than appreciated previously. The data imply that either a significant fraction of B-CLL cells was selected by a limited set of antigenic epitopes at some point in their development and/or that they derive from a distinct B cell subpopulation with limited Ig V region diversity. These shared, stereotyped Ig molecules may be valuable probes for antigen identification and important targets for cross-reactive idiotypic therapy.