918 resultados para Siglos IV-V


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The protonation constants of benzylidenepyruvate, 2-chloro-, 4-chlorobenzylidinepyruvate and cinnamylidenepyruvate as well as the stability constants of their binary 1:1 complexes with Cu(II), La(III), Pr(III), Sm(III), Lu(III), Sc(III) and Th(IV) have been determined spectrophotometrically in an aqueous medium at 25 °C and ionic strength 0.500 M, held with sodium perchlorate. Coordination centres in the aforementioned ligands are suggested. © 1995.

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The type IV secretion system (T4SS) is used by Gram-negative bacteria to translocate protein and DNA substrates across the cell envelope and into target cells. Xanthomonas citri subsp. citri contains two copies of the T4SS, one in the chromosome and the other is plasmid-encoded. To understand the conditions that induce expression of the T4SS in Xcc, we analyzed, in vitro and in planta, the expression of 18 ORFs from the T4SS and 7 hypothetical flanking genes by RT-qPCR. As a positive control, we also evaluated the expression of 29 ORFs from the type III secretion system (T3SS), since these genes are known to be expressed during plant infection condition, but not necessarily in standard culture medium. From the 29 T3SS genes analyzed by qPCR, only hrpA was downregulated at 72 h after inoculation. All genes associated with the T4SS were downregulated on Citrus leaves 72 h after inoculation. Our results showed that unlike the T3SS, the T4SS is not induced during the infection process.

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Generic characters of Irundisaua Martins & Galileo, 2005 are expanded (antennal formula, width of prosternal process inferior or equal to the diameter of procoxa, protibia enlarged and flattened) and two species are transferred from Acanthoderes Audinet-Serville, 1835: I. forsteri (Tippmann, 1960) comb. nov from Peru and Brazil (Amazonas) and I. ucayalensis (Tippmann,1960) comb. nov from Ecuador, Peru and Brazil (Amazonas).Three new genera are described: (1) Catuana gen. nov., type species, C. spinicornis (Tippmann, 1960) comb. nov, characterized by the mesosternal tubercle; (2) Mundeu gen. nov, type species, M. maculicollis (Bates, 1861) comb. nov, with rounded sides of protorax and expanded protibiae; (3) Urangaua gen. nov, with eyes divided and finelly granulated, length of antenomeres III-IV subequal to V-XI; the genus is proposed of two species: U. analis Melzer, 1935 comb. nov, type species, and U. subanalis (Zajciw,1964) comb. nov. A key to the species of Urangaua is added.

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During their evolution, animals have developed a set of cysteine-rich peptides capable of binding various extracellular sites of voltage-gated sodium channels (VGSC). Sea anemone toxins that target VGSCs delay their inactivation process, but little is known about their selectivities. Here we report the investigation of three native type 1 toxins (CGTX-II, delta-AITX-Bcg1a and delta-AITX-Bcg1b) purified from the venom of Bunodosoma cangicum. Both delta-AITX-Bcg1a and delta-AITX-Bcg1b toxins were fully sequenced. The three peptides were evaluated by patch-clamp technique among Nav1.1-1.7 isoforms expressed in mammalian cell lines, and their preferential targets are Na(v)1.5 > 1.6 > 1.1. We also evaluated the role of some supposedly critical residues in the toxins which would interact with the channels, and observed that some substitutions are not critical as expected. In addition, CGTX-II and delta-AITX-Bcg1a evoke different shifts in activation/inactivation Boltzmann curves in Nav1.1 and 1.6. Moreover, our results suggest that the interaction region between toxins and VGSCs is not restricted to the supposed site 3 (S3-54 linker of domain IV), and this may be a consequence of distinct surface of contact of each peptide vs. targeted channel. Our data suggest that the contact surfaces of each peptide may be related to their surface charges, as CGTX-II is more positive than delta-AITX-Bcg1a and delta-AITX-Bcg1b. (C) 2011 Elsevier Inc. All rights reserved.

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The compound [PbPh2(NO3)(2)(H2O)(2)] was synthesized and characterized by spectroscopic methods (IR; H-1, C-13 and Pb-207 NMR) and mass spectrometry. An X-ray diffraction study showed that the crystal is a supramolecular tridimensional network of hydrogen-bonded PbPh2(NO3)(2)(H2O)(2) units in which the Pb atom is octacoordinated and adopts a distorted hexagonal bipyramidal geometry, with four O (bidentate nitrate) and two O (water) atoms in equatorial positions and two C-phenyl atoms in axial positions. The crystal of [PbMe3(NO3)(H2O)], obtained as a byproduct in the synthesis of PbMe2(NO3)(2), contains chains of hydrogen-bonded PbMe3(NO3)(H2O) units in which the Pb atom is pentacoordinated with a slightly distorted trigonal bipyramidal environment. In this arrangement the three C-methyl atoms are equatorial and the O atoms from the monodentate nitrate and the water molecule are axial. (C) 2011 Elsevier Ltd. All rights reserved.

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Background Chyle fistulas may occur after left neck dissections that include level IV, due to injury of the thoracic duct or of 1 of its major branches. Despite being unusual, this complication carries substantial postoperative morbidity and even mortality. So far, no effective intraoperative maneuver has been reported to detect this fistula at the end of a neck dissection. In this cohort study, we sought to describe a simple new maneuver, intraoperative abdominal compression, which can effectively help to identify an open major lymphatic duct on level IV at the end of a neck dissection. Patients and Methods From March 1989 to September 2010, 206 patients underwent neck dissections involving left level IV, and underwent intraoperative abdominal compression. There were 119 men and 87 women, with ages ranging from 18 to 81 years (median, 52 years). One hundred forty-four patients had squamous cell carcinomas, 54 had thyroid carcinomas, 5 had malignant melanomas, and 3 had salivary cancers. Distribution by type of left neck dissection was: selective including levels II, III, and IV (73 cases; 35.4%), selective including levels II, III, IV, and V (55 cases; 26.6%), selective including levels I, II, III, and IV (12 cases; 5.8%), modified radical (47 cases; 22.8%), and radical (19 cases; 9.2%). In all cases, at the end of the procedure, the endotracheal tube was temporarily disconnected from the ventilator. Keeping the dissected level IV area under clear visualization, an abdominal compression was performed. At this moment, any detected lymphatic leak was carefully clamped and tied with nonabsorbable sutures. After ventilating the patient, the intraoperative abdominal compression was repeated to reassure complete occlusion of the lymphatic vessel. Results In 13 cases (6.3%), a chyle leak was detected after performing the intraoperative abdominal compression. All leaks except for 2 were successfully controlled after 1 attempt. In these 2 patients, a patch of muscle and fat tissue was applied with fibrin glue on the top. In 1 of these patients, another chyle leak in a different location was detected only at the second intraoperative abdominal compression, and was also effectively closed. Postoperatively, there were 2 (1%) chyle fistulas, both among these 13 cases, and all were successfully managed with clinical measures only. No fistulas occurred among the remaining 193 patients in whom intraoperative abdominal compression did not demonstrate lymphatic leak. Conclusion To our knowledge, this is the first description of a specific maneuver to actively detect a lymphatic fistula at the end of a left neck dissection involving level IV. In this study, intraoperative abdominal compression was able to detect an open lymphatic vessel in 6.3% of the cases, as well as to assure its effective sealing in the remaining 93.7% of the patients. Moreover, no life-threatening high-volume fistula was noted in this study. (C) 2012 Wiley Periodicals, Inc. Head Neck, 2012

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Statement of problem. The retention of an Aramany Class IV removable partial dental prosthesis can be compromised by a lack of support. The biomechanics of this obturator prosthesis result in an unusual stress distribution on the residual maxillary bone. Purpose. This study evaluated the biomechanics of an Aramany Class IV obturator prosthesis with finite element analysis and a digital 3-dimensional (3-D) model developed from a computed tomography scan; bone stress was evaluated according to the load placed on the prosthesis. Material and methods. A 3-D model of an Aramany Class IV maxillary resection and prosthesis was constructed. This model was used to develop a finite element mesh. A 120 N load was applied to the occlusal and incisal platforms corresponding to the prosthetic teeth. Qualitative analysis was based on the scale of maximum principal stress; values obtained through quantitative analysis were expressed in MPa. Results. Under posterior load, tensile and compressive stresses were observed; the tensile stress was greater than the compressive stress, regardless of the bone region, and the greatest compressive stress was observed on the anterior palate near the midline. Under an anterior load, tensile stress was observed in all of the evaluated bone regions; the tensile stress was greater than the compressive stress, regardless of the bone region. Conclusions. The Aramany Class IV obturator prosthesis tended to rotate toward the surgical resection when subjected to posterior or anterior loads. The amount of tensile and compressive stress caused by the Aramany Class IV obturator prosthesis did not exceed the physiological limits of the maxillary bone tissue. (J Prosthet Dent 2012;107:336-342)

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The aim of this study was to evaluate the potential application of biodegradable nanoparticles containing a photosensitizer in photodynamic therapy. The poly (D,L lactic-co-glycolic acid) nanoparticles were studied by steady-state techniques, time-resolved fluorescence, and laser flash photolysis. The external morphology of the nanoparticles was established by scanning electron microscopy, and the biological activity was evaluated by in vitro cell culture by 3-(4,5 dimethylthiazol-2,5 biphenyl) tetrazolium bromide assay. The particles were spherical in shape exhibiting a 435 nm diameter with a low tendency to aggregate. The loading efficiency was 77%. The phthalocyanine-loaded-nanoparticles maintained their photophysical behavior after encapsulation. The cellular viability was determined, obtaining 70% of cellular death. All the performed physical-chemical, photophysical, and photobiological measurements indicated that the phthalocyanine-loaded-nanoparticles are a promising drug delivery system for photodynamic therapy and photoprocesses. (C) 2012 Laser Institute of America.

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LipL32 is the most abundant outer membrane protein from pathogenic Leptospira and has been shown to bind extracellular matrix (ECM) proteins as well as Ca2+. Recent crystal structures have been obtained for the protein in the apo-and Ca2+-bound forms. In this work, we produced three LipL32 mutants (D163-168A, Q67A, and S247A) and evaluated their ability to interact with Ca2+ and with ECM glycoproteins and human plasminogen. The D163-168A mutant modifies aspartate residues involved in Ca2+ binding, whereas the other two modify residues in a cavity on the other side of the protein structure. Loss of calcium binding in the D163-D168A mutant was confirmed using intrinsic tryptophan fluorescence, circular dichroism, and thermal denaturation whereas the Q67A and S247A mutants presented the same Ca2+ affinity as the wild-type protein. We then evaluated if Ca2+ binding to LipL32 would be crucial for its interaction with collagen type IV and plasma proteins fibronectin and plasminogen. Surprisingly, the wild-type protein and all three mutants, including the D163-168A variant, bound to these ECM proteins with very similar affinities, both in the presence and absence of Ca2+ ions. In conclusion, calcium binding to LipL32 may be important to stabilize the protein, but is not necessary to mediate interaction with host extracellular matrix proteins.

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Signal transduction pathways mediated by cyclic-bis(3'→5')-dimeric GMP (c-di-GMP) control many important and complex behaviors in bacteria. C-di-GMP is synthesized through the action of GGDEF domains that possess diguanylate cyclase activity and is degraded by EAL or HD-GYP domains with phosphodiesterase activity. There is mounting evidence that some important c-di-GMP-mediated pathways require protein-protein interactions between members of the GGDEF, EAL, HD-GYP and PilZ protein domain families. For example, interactions have been observed between PilZ and the EAL domain from FimX of Xanthomonas citri (Xac). FimX and PilZ are involved in the regulation of type IV pilus biogenesis via interactions of the latter with the hexameric PilB ATPase associated with the bacterial inner membrane. Here, we present the crystal structure of the ternary complex made up of PilZ, the FimX EAL domain (FimXEAL) and c-di-GMP. PilZ interacts principally with the lobe region and the N-terminal linker helix of the FimXEAL. These interactions involve a hydrophobic surface made up of amino acids conserved in a non-canonical family of PilZ domains that lack intrinsic c-di-GMP binding ability and strand complementation that joins β-sheets from both proteins. Interestingly, the c-di-GMP binds to isolated FimXEAL and to the PilZ-FimXEAL complex in a novel conformation encountered in c-di-GMP-protein complexes in which one of the two glycosidic bonds is in a rare syn conformation while the other adopts the more common anti conformation. The structure points to a means by which c-di-GMP and PilZ binding could be coupled to FimX and PilB conformational states

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Cosa e’ stato fatto e il fine della ricerca in questi tre anni si è esaminato il materiale edito sui sarcofagi del periodo in esame, sui culti funerari, i problemi religiosi ed artistici. Per trovare confronti validi si sono resi necessari alcuni viaggi sia in Italia che all’estero. Lo scopo della ricerca è stato quello di “leggere” i messaggi insiti nelle figurazioni delle casse dei sarcofagi, per comprendere meglio la scelta dei committenti verso determinati temi e la ricezione di questi ultimi da parte del pubblico. La tomba, infatti, è l’ultima traccia che l’uomo lascia di sé ed è quindi importante cercare di determinare l’impatto psicologico del monumento funerario sul proprietario, che spesso lo acquistava quando ancora era in vita, e sui familiari in visita alla tomba durante la celebrazione dei riti per i defunti. Nell’ultimo anno, infine, si è provveduto a scrivere la tesi suddivindendo i capitoli e i pezzi in base all’argomento delle figurazioni (mitologici, di virtù, etc.). I capitoli introduttivi Nel primo capitolo di introduzione si è cercato di dare un affresco per sommi capi del periodo storico in esame da Caracalla a Teodosio e della Chiesa di III e IV secolo, mettendo in luce la profonda crisi che gravava sull’Impero e le varie correnti che frammentavano il cristianesimo. In particolare alcune dispute, come quella riguardante i lapsi, sarà alla base di ipotesi interpretative riguardanti la raffigurazione del rifiuto dei tre giovani Ebrei davanti a Nabuchodonosor. Nel capitolo seguente vengono esaminati i riti funerari e il ruolo dei sarcofagi in tali contesti, evidenziando le diverse situazioni emotive degli osservatori dei pezzi e, quindi, l’importanza dei temi trattati nelle casse. I capitolo Questo capitolo tratta dei sarcofagi mitologici. Dopo una breve introduzione, dove viene spiegata l’entrata in uso dei pezzi in questione, si passa alla discussione dei temi, suddivisi in paragrafi. La prima classe di materiali è qualla con la “caduta di Fetonte” la cui interpretazione sembra chiara: una tragedia familiare. Il compianto sul corpo di un ragazzo morto anzi tempo, al quale partecipa tutto il cosmo. L’afflizione dei familiari è immane e sembra priva di una possibile consolazione. L’unico richiamo a riprendere a vivere è solo quello del dovere (Mercurio che richiama Helios ai propri impegni). La seconda classe è data dalle scene di rapimento divino visto come consolazione e speranza in un aldilà felice, come quelle di Proserpina e Ila. Nella trasposizione della storia di Ila è interessante anche notare il fatto che le ninfe rapitrici del giovane – defunto abbiano le sembianze delle parenti già morte e di un fanciullo, probabilmente la madre, la nonna e un fratello deceduto anzi tempo. La terza classe presenta il tema del distacco e dell’esaltazione delle virtù del defunto nelle vesti dei cacciatori mitici Mealeagro, Ippolito e Adone tutti giovani, forti e coraggiosi. In questi sarcofagi ancor più che negli altri il motivo della giovinezza negata a causa della morte è fondamentale per sottolineare ancora di più la disperazione e il dolore dei genitori rimasti in vita. Nella seguente categoria le virtù del defunto sono ancora il tema dominante, ma in chiave diversa: in questo caso l’eroe è Ercole, intento ad affrontare le sue fatiche. L’interpretazione è la virtù del defunto che lo ha portato a vincere tutte le difficoltà incontrate durante la propria vita, come dimostrerebbe anche l’immagine del semidio rappresentato in età diverse da un’impresa all’altra. Vi è poi la categoria del sonno e della morte, con i miti di Endimione, Arianna e Rea Silvia, analizzato anche sotto un punto di vista psicologico di aiuto per il superamento del dolore per la perdita di un figlio, un marito, o, ancora, della sposa. Accanto ai sarcofagi con immagini di carattere narrativo, vi sono numerosi rilievi con personaggi mitici, che non raccontano una storia, ma si limitano a descrivere situazioni e stati d’animo di felicità. Tali figurazioni si possono dividere in due grandi gruppi: quelle con cortei marini e quelle con il tiaso dionisiaco, facendo dell’amore il tema specifico dei rilievi. Il fatto che quello del tiaso marino abbia avuto così tanta fortuna, forse, per la numerosa letteratura che metteva in relazione l’Aldilà con l’acqua: l’Isola dei Beati oltre l’Oceano, viaggi per mare verso il mondo dei morti. Certo in questo tipo di sarcofagi non vi sono esplicitate queste credenze, ma sembrano più che altro esaltare le gioie della vita. Forse il tutto può essere spiegato con la coesistenza, nei familiari del defunto, della memoria retrospettiva e della proiezione fiduciosa nel futuro. Sostanzialmente era un modo per evocare situazioni gioiose e di godimento sensibile, riferendole ai morti in chiave beneaugurale. Per quanto rigurda il tiaso di Bacco, la sua fortuna è stata dettata dal fatto che il suo culto è sempre stato molto attivo. Bacco era dio della festa, dell’estasi, del vino, era il grande liberatore, partecipe della crescita e della fioritura, il grande forestiero , che faceva saltare gli ordinamenti prestabiliti, i confini della città con la campagna e le convenzioni sociali. Era il dio della follia, al quale le menadi si abbandonavano nella danza rituale, che aggrediva le belve, amante della natura, ma che penetra nella città, sconvolgendola. Del suo seguito facevano parte esseri ibridi, a metà tra l’ordine e la bestialità e animali feroci ammansiti dal vino. I suoi nemici hanno avuto destini orribili di indicibile crudeltà, ma chi si è affidato anima e corpo a lui ha avuto gioia, voluttà, allegria e pienezza di vita. Pur essendo un valente combattente, ha caratteri languidi e a tratti femminei, con forme floride e capelli lunghi, ebbro e inebriante. Col passare del tempo la conquista indiana di alessandro si intrecciò al mito bacchico e, a lungo andare, tutti i caratteri oscuri e minacciosi della divinità scomparirono del tutto. Un esame sistematico dei temi iconografici riconducibili al mito di Bacco non è per nulla facile, in quanto l’oggetto principale delle raffigurazioni è per lo più il tiaso o come corteo festoso, o come gruppi di figure danzanti e musicanti, o, ancora, intento nella vendemmia. Ciò che interessava agli scultori era l’atmosfera gioiosa del tiaso, al punto che anche un episodio importante, come abbiamo visto, del ritrovamento di Arianna si pèerde completamente dentro al corteo, affollatissimo di personaggi. Questo perché, come si è detto anche al riguardo dei corte marini, per creare immagini il più possibile fitte e gravide di possibilità associative. Altro contesto iconografico dionisiaco è quello degli amori con Arianna. Sui sarcofagi l’amore della coppia divina è raffigurato come una forma di stupore e rapimento alla vista dell’altro, un amore fatto di sguardi, come quello del marito sulla tomba della consorte. Un altro tema , che esalta l’amore, è senza ombra di dubbio quello di Achille e Pentesilea, allegoria dell’amore coniugale. Altra classe è qualla con il mito di Enomao, che celebra il coraggio virile e l’attitudine alla vittoria del defunto e, se è presente la scena di matrimonio con Ippodamia, l’amore verso la sposa. Infine vi sono i sarcofagi delle Muse: esaltazione della cultura e della saggezza del morto. II capitolo Accanto ad i grandi ambiti mitologici dei due tiasi del capitolo precedente era la natura a lanciare un messaggio di vita prospera e pacifica. Gli aspetti iconografici diq uesto tema sono due: le stagioni e la vita in un ambiente bucolico. Nonostante la varietà iconografica del soggetto, l’idea di fondo rimane invariata: le stagioni portano ai morti i loro doni affinchè possano goderne tutto l’anno per l’eternità. Per quanto riguarda le immagini bucoliche sono ispirate alla vita dei pastori di ovini, ma ovviamente non a quella reale: i committenti di tali sarcofagi non avevano mai vissuto con i pastori, né pensavano di farlo i loro parenti. Le immagini realistiche di contadini, pastori, pescatori, tutte figure di infimo livello sociale, avevano assunto tratti idilliaci sotto l’influsso della poesia ellenistica. Tutte queste visioni di felicità mancano di riferimenti concreti sia temporali che geografici. Qui non vi sono protagonisti e situazioni dialogiche con l’osservatore esterno, attraverso la ritrattistica. I defunti se appaiono sono all’interno di un tondo al centro della cassa. Nei contesti bucolici, che andranno via, via, prendendo sempre più piede nel III secolo, come in quelli filosofici, spariscono del tutto le scene di lutto e di cordoglio. Le immagini dovevano essere un invito a godersi la vita, ma dovevano anche dire qualcosa del defunto. In una visione retrospettiva, forse, si potrebbero intendere come una dichiarazione che il morto, in vita, non si era fatto mancare nulla. Nel caso opposto, poteve invece essere un augurio ad un’esistenza felice nell’aldilà. III capitolo Qui vengono trattati i sarcofagi con l’esaltazione e l’autorappresentazione del defunto e delle sue virtù in contesti demitizzati. Tra i valori ricorrenti, esaltati nei sarcofagi vi è l’amore coniugale espresso dal tema della dextrarum iunctio, simbolo del matrimonio, la cultura, il potere, la saggezza, il coraggio, esplicitato dalle cacce ad animali feroci, il valore guerriero e la giustizia, dati soprattutto dalle scene di battaglia e di giudizio sui vinti. IV capitolo In questo capitolo si è provato a dare una nuova chiave di lettura ai sarcofagi imperiali di S. Elena e di Costantina. Nel primo caso si tratterebbe della vittoria eterna sul male, mentre nel secondo era un augurio di vita felice nell’aldilà in comunione con Dio e la resurrezione nel giorno del giudizio. V capitolo Il capitolo tratta le mediae voces, quei pezzi che non trovano una facile collocazione in ambito religioso poiché presentano temi neutri o ambivalenti, come quelli del buon pastore, di Prometeo, dell’orante. VI capitolo Qui trovano spazio i sarcofagi cristiani, dove sono scolpite varie scene tratte dalle Sacre Scritture. Anche in questo caso si andati al di là della semplice analisi stilistica per cercare di leggere il messaggio contenuto dalle sculture. Si sono scoperte preghiere, speranze e polemiche con le correnti cristiane considerate eretiche o “traditrici” della vera fede, contro la tradizionale interpretazione che voleva le figurazioni essenzialmente didascaliche. VII capitolo Qui vengono esposte le conclusioni da un punto di vista sociologico e psicologico.

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The study of the objects LaTène type found in middle-eastern alpine region (Trentino Alto Adige-Südtirol, Engadina, North Tirol, Voralberg and Villach basin) is aimed to a better comprehension of the complex net of relationships established among the Celts, settled both in the central Europe territories and, since the IV century b.C., in the Po Plain, and the local populations. The ancient authors, who called the inhabitants of this area Raeti, propose for this territory the usual pattern according to which, the population of a region was formed consequently to a migration or was caused by the hunting of pre-existing peoples. The archaeologists, in the last thirty years, recognized a cultural facies typical of the middle-eastern alpine territory during the second Iron Age, and defined that as Fritzens-Sanzeno culture (from the sites of Fritzens, Inn valley, and Sanzeno, Non Valley). The so-called Fritzens-Sanzeno culture spread out without breaks from the material culture of the final Bronze Age and the first Iron Age. This local substratum, characterized by a ceramic repertoire strongly standardized, by peculiar architectural solutions and by a particular typology of rural sacred places (Brandopferplätze), accepted, above all during the second Iron Age, the strong influences coming from the Etruscan world and from the Celtic one (evident in the presence of objects of ornament, of glass artefacts, of elements of the weaponry and of coins). The objects LaTène type become, with different degrees of reliability, important markers of the relationships existing between the Celts and the Raeti, although the ways of interaction (cultural influence, people's movements, commercial exchanges, gifts among élites etc.) is not still clear. The revision of published data and the study of unpublished materials allows to define a rich and articulated picture both to chronological level and to territorial one.

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The prognostic relevance of additional cytogenetic findings at diagnosis of chronic myeloid leukemia (CML) is unclear. The impact of additional cytogenetic findings at diagnosis on time to complete cytogenetic (CCR) and major molecular remission (MMR) and progression-free (PFS) and overall survival (OS) was analyzed using data from 1151 Philadelphia chromosome-positive (Ph(+)) CML patients randomized to the German CML Study IV. At diagnosis, 1003 of 1151 patients (87%) had standard t(9;22)(q34;q11) only, 69 patients (6.0%) had variant t(v;22), and 79 (6.9%) additional cytogenetic aberrations (ACAs). Of these, 38 patients (3.3%) lacked the Y chromosome (-Y) and 41 patients (3.6%) had ACAs except -Y; 16 of these (1.4%) were major route (second Philadelphia [Ph] chromosome, trisomy 8, isochromosome 17q, or trisomy 19) and 25 minor route (all other) ACAs. After a median observation time of 5.3 years for patients with t(9;22), t(v;22), -Y, minor- and major-route ACAs, the 5-year PFS was 90%, 81%, 88%, 96%, and 50%, and the 5-year OS was 92%, 87%, 91%, 96%, and 53%, respectively. In patients with major-route ACAs, the times to CCR and MMR were longer and PFS and OS were shorter (P < .001) than in patients with standard t(9;22). We conclude that major-route ACAs at diagnosis are associated with a negative impact on survival and signify progression to the accelerated phase and blast crisis.

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Numerous bacterial pathogens subvert cellular functions of eukaryotic host cells by the injection of effector proteins via dedicated secretion systems. The type IV secretion system (T4SS) effector protein BepA from Bartonella henselae is composed of an N-terminal Fic domain and a C-terminal Bartonella intracellular delivery domain, the latter being responsible for T4SS-mediated translocation into host cells. A proteolysis resistant fragment (residues 10-302) that includes the Fic domain shows autoadenylylation activity and adenylyl transfer onto Hela cell extract proteins as demonstrated by autoradiography on incubation with α-[(32)P]-ATP. Its crystal structure, determined to 2.9-Å resolution by the SeMet-SAD method, exhibits the canonical Fic fold including the HPFxxGNGRxxR signature motif with several elaborations in loop regions and an additional β-rich domain at the C-terminus. On crystal soaking with ATP/Mg(2+), additional electron density indicated the presence of a PP(i) /Mg(2+) moiety, the side product of the adenylylation reaction, in the anion binding nest of the signature motif. On the basis of this information and that of the recent structure of IbpA(Fic2) in complex with the eukaryotic target protein Cdc42, we present a detailed model for the ternary complex of Fic with the two substrates, ATP/Mg(2+) and target tyrosine. The model is consistent with an in-line nucleophilic attack of the deprotonated side-chain hydroxyl group onto the α-phosphorus of the nucleotide to accomplish AMP transfer. Furthermore, a general, sequence-independent mechanism of target positioning through antiparallel β-strand interactions between enzyme and target is suggested.