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Effect of Abelson murine leukemia virus on granulocytic differentiation and interleukin-3 dependence of a murine progenitor cell line
No full textThe murine diploid hematopoietic cell line 32D C13 strictly requires interleukin-3 (IL-3) for proliferation. When 32D C13 cells are transferred to IL-3-free medium which contains recombinant human granulocyte colony stimulating factor (rhG-CSF), the cell number increases four- to five-fold, and after 14 days the whole cell population is differentiated into morphologically normal and myeloperoxidase- and lactoferrin-positive metamyelocytes and granulocytes. Infection with Abelson murine leukemia virus (A-MuLV) of 32D C13 cells growing in the presence of IL-3 induces, within 2 weeks, the appearance of cells that are IL-3-independent for growth. The latter cells lack myeloid, T and B cell markers, and are unable to differentiate, even in the presence of very high doses of rhG-CSF. However, once the 32D C13 cells have been exposed to G-CSF, they become resistant to the transforming effects of A-MuLV as judged by the appearance of the IL-3-independent clones. These findings suggest that the ability of Abelson virus to transform immature progenitor cells is due to interference of the v-abl gene product with the mechanism that control the commitment of the cells to differentiate
Il principe Giovanni Torlonia (1873-1938) e il culto del pittoresco. Architetture e paesaggi d’acque nella tenuta di Porto a Fiumicino
Full text linkLa ricostruzione della storia novecentesca delle tenute romane di un importante e peculiare committente come il principe Giovanni Torlonia (1873-1938) del ramo Borghese ha consentito di analizzare nel dettaglio le fasi delle trasformazioni otto-novecentesche dell’esteso territorio rurale di Roma, caratterizzato da una serie di rilevanti siti archeologici. Nel corso della prima metà del Novecento si assistette all’epocale passaggio da un’immagine di “Campagna”, contraddistinta da una serie di paesaggi arretrati ma pittoreschi, ad un’altra di “Agro” legato ad una nuova idea di spazio agricolo industrializzato.
Ripercorrere la storia delle opere artistiche, architettoniche ed edilizie commissionate da Giovanni Torlonia in un arco temporale compreso tra gli ultimi anni dell’Ottocento e il primo Trentennio del Novecento ha significato delineare il profilo di una figura poliedrica di aristocratico cripto-architetto che, sull’illustre esempio del nonno materno Alessandro (1800-1886), ebbe il merito di coinvolgere nella riorganizzazione delle sue tenute una vasta gamma di figure professionali, rappresentate da architetti, ingegneri idraulici, costruttori e agronomi.
Questo studio ha avuto il suo avvio dalla ricostruzione della consistenza delle proprietà Torlonia agli inizi del Novecento nel momento in cui queste furono ereditate dal principe Giovanni: ne è emerso un insieme numerosissimo di tenute, comprese tra il Suburbio romano e il territorio bolognese, all’interno del quale spiccarono per l’importantissima presenza di siti archeologici e naturalistici le tenute romane-laziali dell’Appia Antica, della Caffarella, di Roma Vecchia, di Ceri, di Castel Gandolfo e di Porto a Fiumicino.
Proprio quest’ultimo contesto, contraddistinto dalla bonifica novecentesca del “Lago” di Traiano, in epoca romana porto di Roma imperiale, ha costituito il paradigmatico esempio dell’attuazione di un “programma” innovativo, basato sul principio della “riconversione” industriale di un paesaggio rurale, fino a poco tempo prima inospitale e malarico, in nuovo spazio per il lavoro e il confortevole abitare colonico.
La ricostruzione storica delle trasformazioni della tenuta di Porto è stata l’occasione per analizzare un esteso campionario di progetti edilizi, predisposti dall’architetto Lorenzo Corrado Cesanelli e dagli ingegneri dell’Amministrazione Torlonia. Il risultato ottenuto dal principe Torlonia consistette nella fondazione di un nuovo ed efficiente insediamento agricolo, sviluppato lungo la via Portuense, all’interno del quale la Villa di Porto, affacciata sul “Lago” di Traiano, e la moderna Casetta dell’Isolotto, situata nel Litorale di Fiumicino, costituivano per il Principe le sue residenze predilette.
Nella tenuta di Porto l’immagine degli antichi ruderi delle strutture portuali, non più abbinati ad un romantico ed ostile paesaggio lacustre, grazie al loro rinnovato valore di “memoria”, divennero per la stessa ideologia fascista “incoraggiamento” per l’auspicata riattivazione di una nuova infrastruttura portuale sul Litorale romano.
Lo studio delinea le più recenti vicende di questo territorio, pesantemente trasformato nella seconda metà del Novecento dal nuovo Aeroporto Intercontinentale Leonardo da Vinci. All’interno dell’odierno paesaggio conurbato di Fiumicino il “Lago” di Traiano con l'adiacente "Oasi di Porto" rappresenta un “brano” superstite di quello che un tempo era l’esteso e pittoresco Agro Portuense, esaltato da Goffredo Filibeck e Giuseppe Lugli nel loro studio pubblicato nel 1935
Stage-related proliferative activity determines c-myb functional requirements during normal human hematopoiesis.
No full textTo determine if MYB protein is preferentially required during specific stages of normal human hematopoiesis we incubated normal marrow mononuclear cells (MNC) with c-myb antisense oligodeoxynucleotides. Treated cells were cultured in semisolid medium under conditions designed to favor the growth of specific progenitor cell types. Compared with untreated controls, granulocyte-macrophage (GM) CFU-derived colonies decreased 77% when driven by recombinant human (rH) IL-3, and 85% when stimulated by rH GM colony-stimulating factor (CSF); erythroid burst-forming unit (BFU-E)- and CFU-E-derived colonies decreased 48 and 78%, respectively. In contrast, numbers of G-CSF-stimulated granulocyte colonies derived from antisense treated MNC were unchanged from controls, though the numbers of cells composing these colonies decreased approximately 90%. Similar results were obtained when MY10+ cells were exposed to c-myb antisense oligomers. When compared with untreated controls, numbers of CFU-GM and BFU-E colonies derived from MY10+ cells were unchanged, but the numbers of cells composing these colonies were reduced approximately 75 and greater than 90%, respectively, in comparison with controls. c-myc sense and antisense oligomers were without significant effect in these assays. Using the reverse transcription-polymerase chain reaction, c-myb mRNA was detected in developing hematopoietic cells on days 0-8. At day 14 c-myb expression was no longer detectable using this technique. These results suggest that c-myb is required for proliferation of intermediate-late myeloid and erythroid progenitors, but is less important for lineage commitment and early progenitor cell amplification
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Down-regulated c-myb expression inhibits DNA synthesis of T-leukemia cells in most patients.
No full textWe have investigated the functional relevance of c-myb expression for DNA synthesis in patients' T-leukemia cells. [3H]Thymidine incorporation assays of 32 patients' leukemia cells exposed in vitro to c-myb sense or antisense oligodeoxynucleotides served to define two groups of patients: a responder group whose leukemia cells showed 2- to 16-fold lower levels of [3H]thymidine incorporation in c-myb antisense-treated cultures than in c-myb sense-treated cultures (20 patients) and a nonresponder group whose cells showed comparable [3H]thymidine incorporation levels in either c-myb sense- or antisense-treated cultures (12 patients). Down-regulation of c-myb mRNA levels in cells exposed to c-myb antisense oligodeoxynucleotides was comparable in both groups of patients, indicating that differential sensitivity to c-myb antisense oligodeoxynucleotides was not due to differential uptake of these oligodeoxynucleotides. DNA polymerase alpha mRNA levels were down-regulated in cells from the responders but were unaffected in the nonresponder group. These results suggest that c-myb is required for DNA synthesis in cells of many but not all T-leukemia patients and that leukemia cells in which DNA synthesis is not inhibited despite down-regulation of c-myb expression may have undergone some genetic change(s) that obviate(s) the requirement for myb protein
Increased monocyte phagocytosis and decreased lymphocyte mitogen reactivity in colorectal cancer patients.
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