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Fil: Cargnel, M. D. Universidad de Buenos Aires. Facultad de Agronomía. Buenos Aires, Argentina. Fil: Orchansky, A. L. Universidad Nacional del Sur. Departamento de Agronomía. Bahía Blanca, Buenos Aires, Argentina. Fil: Brevedan, R. E. Universidad Nacional del Sur. Departamento de Agronomía. Bahía Blanca, Buenos Aires, Argentina. Fil: Baioni, S. S. Universidad Nacional del Sur. Departamento de Agronomía. Bahía Blanca, Buenos Aires´, Argentina. Fil: Fioretti, M. N. Universidad Nacional del Sur. Departamento de Agronomía. Bahía Blanca, Buenos Aires, Argentina. Two field experiments were carried out in a semiarid region of Argentina over a soybean (Glycine max L. Merrill) field. The sites of study were San Adolfo (39˚ 23’ S, 62˚ 22’ W, 22 m.a.s.l.) and Nueva Roma (38˚ 29’ S, 62˚ 39’ W, 70 m.a.s.l.). Soybeans were planted on Jan 4 (San Adolfo) and Nov 27 (Nueva Roma) in 0.75 m wide rows and at 400000 pl/ha during two consecutive growing seasons. Energy balance and evapotranspiration (ET) were estimated during the reproductive stages from full bloom (R2) to full maturity (R8). In Nueva Roma ET or latent heat flux (LE) was estimated using the Bowen ratio-energy balance (BREB) (LEb) and the Priestley -Taylor equation (LEPT) with αPT=1.26, 48 h after irrigation or rain. Both methods could be used to predict ET since the ratio LEb/LEPT ranged between 0.83 and 0.95. The observed Bowen ratio values were almost 0 during and after rain and increased to approximately 0.45 several days after rain. In San Adolfo LE was estimating using the Priestley -Taylor equation. For both sites the regression analysis for comparison available energy (Rn-G) and LE using BREB or LEPT indicated that, approximately 90% of the available energy was consumed by LE without detecting significative advective conditions. tbls., grafs.

Extract: Marco Cremaschi Carlotta Fioretti The starting hypothesis of this chapter is that the two different concepts of the diverse city and the intercultural city can be applied interchangeably to describe and govern multi-ethnic urban settings, the difference being more a matter of scale than of nature. Diversity and interculturalism share, in fact, the same duplicity: a normative content combined with an analytic orientation. The former, however, addresses mainly the ordinary configuration of places while the latter allows the discussion of rights and political principles. Are the diverse city and the intercultural city the same, then? The answer is affirmative, but conditional upon clearing both concepts of ideological deposits. Interculturalism, in particular, describes the attitude of governments towards integration intended as a process of exchange and interaction between the host and the immigrant population. At the same time, it suggests a normative model for balancing and accepting these exchanges. Interculturalism has...

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This study focused on the two major processes critical for plant establishment: Seed germination and seedling survival. We determined the effects of (1) water stress and temperature on the germination, and (2) water stress on early seedling growth of Digitaria eriantha cv ‘Irene’. Seeds harvested in 2007 were used for temperature studies, and those coming from 2006 and 2007 for water stress studies. In 2009, viability decreased by 65.4% from 2006 to 2007. During the first twenty-four hours, germination was more than 50% at constant (30 or 35°C) than alternating (10/30 or 10/35°C) temperatures, although total germination was about 80% for all temperature treatments. Polyethylene glycol 8000 was used to impose water stress conditions. Germination percentages and coefficients of velocity decreased with decreasing water potentials. Early seedling growth was smaller at lower water potentials. D. eriantha cv ‘Irene’ appeared to germinate within a wide range of temperatures, but it varied greatly in germination response to water potentials. Results suggest that this species could be planted in late spring-early summer, when seedbed temperatures are increasing and soil moisture might still be adequate., Facultad de Ciencias Agrarias y Forestales

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International audience

International audience

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n vivo exposure of tumor-bearing mice to the antineoplastic agent 5-(3,3-dimethyl-1-triazenyl)-1H-imidazole-4-carboxamide (DTIC) results in increased immunogenicity of tumor cells, an event often referred to as "chemical xenogenization" (CX). To verify the hypothesis of DTIC-induced somatic mutation(s) as the major mechanism underlying CX, studies were performed to dissociate CX from the onset of drug resistance, which was invoked in the past as an event leading to selection of preexisting immunogenic clones. Therefore, experiments were done with a DTIC-susceptible tumor line treated with DTIC and quinacrine dihydrochloride (Q), an antimutagenic compound, according to selected experimental schedules. At different transplant generations, the CX and the onset of drug resistance were evaluated. The results show that a) Q does not prevent the onset of DTIC resistance, b) DTIC-resistant clones arising after treatment with DTIC plus Q are not immunogenic, and c) CX is selectively antagonized by Q. The present data confirm that DTIC-induced immunogenicity is not the result of a selection mechanism mediated by the drug and give further support to the hypothesis that the molecular mechanism of CX may be related to somatic mutation(s).

Delayed-type hypersensitivity responses, mediated by CD8+ cells and detected by skin test assay, occur in sensitized mice in response to challenge with a class I-restricted synthetic peptide related to a poorly immunogenic tumor rejection Ag, P815AB, of murine mastocytoma cells. Efficient priming for this response, which requires functional CD4+ cells and production of IFN-gamma in the host, is achieved by transfer of dendritic cells (DC) pulsed in vitro with a physical mixture of P815AB and T helper peptides, such as a class II-restricted synthetic peptide of tetanus toxin. We now show that the adjuvant effect of the T helper peptide was associated with the appearance of early and late IL-12 transcripts in the spleens of DC recipient mice, correlated with a late IFN-gamma response, and was negated by serologic ablation of endogenous IL-12 at the time of cell transfer. rIL-12, administered in vivo to the DC recipient mice, could substitute for the T helper peptide in initiating skin test reactivity following transfer of DC pulsed with P815AB alone, leading to Ag-specific production of IFN-gamma by CD4+ and CD8+ T cells. In vitro and in vivo cell depletion experiments suggested the following: 1) the exogenous IL-12 required both CD4+ and CD8+ cells for activity; 2) the immune response initiated by IL-12 relied on later production of IL-12 by the host; and 3) the early adjuvanticity of the exogenous IL-12 involved improved recognition of class II-restricted epitopes of this otherwise poorly immunogenic tumor peptide.

Ag-specific CD8+ cell responses, including delayed-type hypersensitivity in vivo and IFN-gamma production in vitro, are initiated by host immunization with P815AB, a self peptide bearing CTL epitopes and expressed by murine mastocytoma cells. Using P815AB-pulsed dendritic cells (DC) and monitoring class I-restricted skin test reactivity in DC-primed mice, we have previously shown that the development of a Th1-like response to P815AB requires T helper effects, such as those mediated by coimmunization with class II-restricted (helper) peptides or by the use of rIL-12. The adjuvanticity of IL-12 was suggested to involve improved recognition of class II-restricted epitopes of P815AB. In the present study, we provide evidence for the occurrence of I-A(d)-restricted epitopes in the tumor peptide. We also show that in the absence of helper peptide or rIL-12, P81 5AB not only failed to initiate CD8+ cell responses in vivo and in vitro, but resulted in a transient state of functional unresponsiveness, characterized by a profound inability of CD4+ cells to produce IL-2 in vitro. Ag-specific T cell anergy was also observed after neutralization of endogenous IL-12 at the time of priming with P815AB plus helper peptide. All of these effects were reversed by rIL-12, which was added to DC cultures and administered to the DC-recipient mice. Anergy induction may thus contribute to P81 5AB unresponsiveness in vivo. IL-12 may act to prevent or revert anergy to this tumor-associated and self peptide.

Ligation of CD40 on dendritic cells (DC) triggers production of IL-12. Using an adoptive transfer model we have previously shown that rIL-12 acts directly on DC to enhance presentation of an otherwise poorly immunogenic tumor peptide. Using the same experimental model, we now describe a similar adjuvanticity of CD40 ligation on peptide presentation by DC. We also explore the possibility that the IL-12 resulting from CD40 ligation directly affects the APC function of DC, mediating or contributing to the adjuvant effect of CD40 ligation. CD40 engagement in vitro and rIL-12 at concentrations in the range induced by CD40 ligation were equally effective in priming DC for presentation of the tumor peptide in vivo. Remarkably, the copresence in vitro of neutralizing Ab to IL-12, but not to TNF-α, IL-1β, or IFN-γ, ablated the enhancing effect of CD40 engagement on the APC function of DC. These data suggest a major role for autocrine IL-12 in DC modulation via CD40 ligation.

Exposure in vivo of murine L5178Y lymphoma cells to cytoreductive triazene derivatives leads to the generation of immunogenic variant lines expressing new transplantation Ags recognized by CTL. In one such clonal variant (clone D), at least one subset of T cell neoepitopes are provided by proteins previously shown by serology to be products of endogenous retroviral env sequences. We report here on characterization of PCR-amplified gp70 env genes in clone D. Relative to known gp70 sequences in parental cells and in current databases, one gp70 sequence presented four distinct nucleotide changes, two of which were apparently unique to clone D DNA and cDNA upon differential hybridization analysis. Transfection experiments with the entire gp70 gene or subgenic fragments encompassing a single putative mutation showed that products of the mutated env gene or fragments may confer immunogenicity in vivo and susceptibility in vitro to lysis by clone D-primed, H-2Kd- or H-2Ld-restricted CTL. By skin test assay of mice primed with either clone D or three mutated synthetic peptides, evidence was obtained that amino acid substitutions at the relevant positions of the gp70 protein may produce immunogenic T cell epitopes and that these epitopes are expressed in vivo by clone D. These data point to the role of mutated retroviral tumor peptides as rejection Ags in histocompatible hosts.

Background: Surgery is the primary treatment for patients with stage I, II, or IIIA non-small-cell lung cancer (NSCLC). However, long-term survival of NSCLC patients after surgery alone is largely unsatisfactory, and the role of adjuvant chemotherapy in patient survival has not yet been established. Methods: Between January 1994 and January 1999, 1209 patients with stage I, II, or IIIA NSCLC were randomly assigned to receive mitomycin C (8 mg/m 2 on day 1), vindesine (3 mg/m 2 on days 1 and 8), and cisplatin (100 mg/m 2 on day 1) every 3 weeks for three cycles (MVP group; n = 606) or no treatment (control group; n = 603) after complete resection. Randomization was stratified by investigational center, tumor size, lymph-node involvement, and the intention to perform radiotherapy. The primary endpoint was overall survival and secondary endpoints were progression-free survival and toxicity associated with adjuvant treatment. Survival curves were analyzed using the log-rank test. All statistical tests were two-sided. Results: After a median follow-up time of 64.5 months, there was no statistically significant difference between the two patient groups in overall survival (hazard ratio = 0.96, 95% confidence interval = 0.81 to 1.13; P = .589) or progression-free survival (hazard ratio = 0.89, 95% confidence interval = 0.76 to 1.03; P = .128). Only 69% of patients received the three planned cycles of MVP. Grades 3 and 4 neutropenia occurred in 16% and 12%, respectively, of patients in the MVP arm. Radiotherapy was completed by 65% of patients in the MVP arm and by 82% of patients in the control group. In the multivariable analysis, only disease stage and sex were associated with survival. Conclusion: This randomized trial failed to prospectively confirm a statistically significant role for adjuvant chemotherapy in completely resected NSCLC. Given the poor compliance with the MVP regimen used in this study, future studies should explore more effective treatments.

L’immigrazione è probabilmente uno dei temi più rilevanti all’interno del dibattito odierno sulle città italiane. Il fenomeno è cresciuto di intensità negli ultimi vent’anni, diventando una realtà consistente che ha un impatto importante dal punto di vista sociale, economico e anche territoriale. Questo è particolarmente vero per una regione come il Lazio, nel 2016 seconda in Italia (dopo la Lombardia) per numero di residenti stranieri, pari a 645.159 persone. Gli studi urbani e la ricerca urbanistica si occupano ormai da alcuni anni in maniera crescente del tema “immigrazione e città”. Quello che forse è meno noto, sia nel dibattito pubblico che in quello specialistico, è che più della metà del fenomeno migratorio in Italia riguarda i centri urbani minori. Questo volume monografico de “I Quaderni di Urbanistica Tre” raccoglie il lavoro di ricerca fatto dall’Unità di Ricerca dell’Università Roma Tre nell’ambito del PRIN “Piccoli Comuni e Coesione Sociale. Politiche e pratiche urbane per l’inclusione sociale e spaziale dei migranti”, e rappresenta un tentativo inedito di raccontare il fenomeno migratorio nella regione Lazio attraverso le pratiche e politiche di inclusione degli immigrati nei piccoli centri urbani. La ricerca PRIN si è svolta tra il 2013 e il 2016, e ha coinvolto sei unità di ricerca con prospettive disciplinari diverse (pianificazione e politiche urbane, sociologia, antropologia e demografia) per indagare in maniera integrata il fenomeno migratorio nei piccoli comuni in diverse aree territoriali del paese. L’obiettivo generale della ricerca era quello di fornire elementi conoscitivi e strumenti operativi per una gestione innovativa delle “società delle diversità” nei comuni di piccola dimensione che devono far fronte a una significativa e crescente presenza di residenti stranieri, rafforzandone le capacità di consolidare la coesione sociale e spaziale (per una discussione dei risultati della ricerca nazionale vedi Balbo 2015).L’indagine condotta dall’Unità di Ricerca Roma Tre si è focalizzata sull’area romano-laziale, esplorando innanzi tutto il contesto politico e amministrativo regionale, individuando le principali leggi, politiche e gli attori che costituiscono il sistema di governance dell’immigrazione (vedi Fioretti et al, 2014; Cremaschi & Fioretti 2015).Inoltre si è ricostruita la strutturazione territoriale del fenomeno, nel tentativo di capire le principali geografie dell’immigrazione (idem) e individuare alcuni comuni che ne rappresentassero la varietà. Questi sono stati oggetto di studio approfondito tramite un approccio misto, ma prevalentemente qualitativo, con un importante lavoro di campo che ha permesso tramite lo strumento dell’intervista e dell’osservazione partecipante di esplorare il tessuto sociale e far emergere i sistemi di incorporazione locale dei migranti.Il presente numero de iQuaderni di UrbanisticaTre dà conto precisamente di questo lavoro di approfondimento fatto su otto comuni del Lazio, più o meno piccoli, restituendo una ricerca che è prima di tutto empirica ed esplorativa. Questo taglio ha una sua precisa ragione d’essere, per riempire il vuoto dato dal fatto che il fenomeno migratorio nei centri minori del Lazio è oggi assolutamente poco studiato. Uno sforzo in questo senso è stato fatto in anni recenti dall’unico importante osservatorio sul fenomeno: il rapporto annuale curato dal Centro Studi e Ricerche Idos, promosso da istituzioni laiche e religiose locali. Le edizioni più recenti dell’Osservatorio Romano sulle Migrazioni hanno infatti lasciato sempre più spazio alle indagini nei territori della ex Provincia di Roma e, in maniera ancora timida, in alcune realtà della regione (cfr. ad esempio Centro Sudi e Ricerche IDOS, 2016). Oltre a questo contributo sistematico, si trovano rari casi di pubblicazioni su immigrazione e centri minori, e spesso si tratta di ricerche con tagli molto specifici (ad esempio Ricci 2012 sul riuso dei centri storici, Omizzolo 2010 sui lavoratori agricoli indiani di Latina, Weber 2004 e Cingolani e Piperno 2005 sui romeni in Provincia di Roma).