In tropical agroecosystems, limited N availability remains a major impediment to increasing yield. A 15N-recovery experiment was conducted in 13 diverse tropical agroecosystems. The objectives were to determine the total recovery of one single 15N application of inorganic or organic N during three to six growing seasons and to establish whether the losses of N are governed by universal principles. Between 7 and 58% (average of 21%) of crop N uptake duringthe first growing season was derived from fertilizer. On average, 79% of crop N was derived from the soil. When 15N-labeled residues were applied, in the first growing season 4% of crop N was derived from the residues. Average recoveries of 15N-labeled fertilizer and residue in crops after the first growing season were 33 and 7%, respectively. Corresponding recoveries in the soil were 38 and 71 %. An additional 6% of the fertilizer and 9.1 % of the residue was recovered by crops during subsequent growing seasons. There were no significant differences in total 15N recovery (average 54%) between N from fertilizer and N from residue. After five growing seasons, more residue N (40%) than fertilizer N (18%) was recovered in the soil, better sustaining the soil organic matter N content. Long-term total recoveries of 15N-labeled fertilizer or residue in the crop and soil were similar. Soil N remained the primary source of N for crops. As higher rainfall and temperature tend to cause higher N losses, management practices to improve N use efficiency and reduce losses in wet tropical regions will remain a challenge.

The diversity of thermophilic bacteria was investigated in four hot springs, three salt marshes and 12 desert sites in Morocco. Two hundred and forty (240) thermophilic bacteria were recovered, identified and characterized. All isolates were Gram positive, rod-shaped, spore forming and halotolerant. Based on BOXA1R-PCR and 16S rRNA gene sequencing, the recovered isolates were dominated by the genus Bacillus (97.5%) represented by B. licheniformis (119), B. aerius (44), B. sonorensis (33), B. subtilis (subsp. spizizenii (2) and subsp. inaquosurum (6)), B. amyloliquefaciens (subsp. amyloliquefaciens (4) and subsp. plantarum (4)), B. tequilensis (3), B. pumilus (3) and Bacillus sp. (19). Only six isolates (2.5%) belonged to the genus Aeribacillus represented by A. pallidus (4) and Aeribacillus sp. (2). In this study, B. aerius and B. tequilensis are described for the first time as thermophilic bacteria. Moreover, 71.25%, 50.41% and 5.41% of total strains exhibited high amylolytic, proteolytic or cellulolytic activity respectively.

Background: Bladder small cell carcinoma is an uncommon tumour. Through a retrospective study we will present the evolution of recurrent and metastatic disease and outcome of patients treated at Léon-Bérard Cancer Centre.

SUMMARYA pot experiment was conducted under glasshouse conditions to investigate the effect of inoculation with four arbuscular mycorrhizal (AM) fungi {Glomus clarum, G. etunicatum, G. manihotis, Gigaspora margarita), either individually or in a mixture, and wdth Rhizobium leguminosarum hiovar phaseoli, on the growth, mineral nutrition, and contribution of biologically fixed Ng, to three nodulating bean {Phaseolus vulgaris) varieties (Carioca, Negro Argel and Rio Tibagi). The ^^N isotope dilution technique and three control crops (non-nodulating bean, Panicum maximum and sorghum) were used to quantify the contribution of Ng fixation. There were significant differences between the capacity of the different AM fungi to infect and colonize the roots of the different bean varieties. Inoculation with AM fungi significantly increased production of dry matter by 8-23 % and the concentration of P in plants by 160-335%. A strongly positive correlation of % root colonization by AM fungi and plant P concentration and accumulation was observed which suggests that the observed inoculation responses were a result of improved P acquisition by the mycorrhizal roots. N derived from the atmosphere increased significantly with AM fungi inoculation, with Carioca showing the best response, followed by Negro Argel and Rio Tibagi, thereby showing the indirect and positive effect of AM fungi inoculation on the Ng-fixing association between Rhizobium and Phaseolus vulgaris.

BackgroundNasopharyngeal non-Hodgkin lymphomas (NNHL) are extremely rare. In this study, we will report the progress achieved in the management of this disease in our institute.MethodsWe retrospectively reviewed the records of 26 patients having primary NNHL who were managed between January 1997 and December 2008, to evaluate and compare their clinical characteristics and treatment outcome. Clinical variables, including age, sex, stage, and treatment modality, were assessed. Disease free survival and overall survival were measured. Survival curves were constructed using the KaplanMeier method. The log-rank test was used to compare them.ResultsMedian age of our patients was 52.7 years. Nasal obstruction, nasal discharge and epistaxis were the frequent symptoms in NNHL patients. Histology of NNHL were mainly large B-cell and follicular lymphoma. Four patients (15.4%) were at stage I, 15 (57.6%) at stage II, and 7 (27%) were at stage III/IV. The patients were treated with chemotherapy alone (27%) or chemotherapy plus radiotherapy (73%). At early stage (stage I/II), the patients were managed with chemo-radiotherapy. When the whole treatment was completed, 18 patients (69.2%) achieved complete response and remained disease free. After 25.9 months median follow-up, overall survival at 1 year was 87% and disease free survival at 1 year was 71%. The difference in term of overall and disease free survival between stage I, II, III and IV was significant (Log rank test: p = 0.02 for overall survival and p = 0.01 for disease free survival).ConclusionFrom our study, we conclude that histological characteristics, principle of treatment and outcome of primary NNHL patients are particular and more studies have to be directed.