Actividad fungicida/fungistática in vitro del fosfito de manganeso contra hongos patógenos habitantes del suelo con soja

Las pudriciones de raíz y tallo (PRYT) en el cultivo de soja causadas por patógenos habitantes del suelo son enfermedades comúnmente encontradas en campos de soja y son una de las causas más importantes de pérdidas económicas. La sensibilidad micelial de Fusarium virguliforme, Fusarium tucumaniae, Sclerotinia sclerotiorum y Macrophomina phaseolina fue evaluada en medio de cultivo agar papa glucosa (25 mL) suplementado con diferentes concentraciones (µg mL-1) de fosfito de manganeso (PhiMn) diluido en agua (0; 25; 37.5; 50; 100; 200; 300; 400; 500; 800 y 1000). La sensibilidad del crecimiento micelial fue analizada usando análisis de regresión lineal logarítmico. La concentración de PhiMn necesaria para inhibir el 50% del crecimiento micelial (CI50) fue calculada. Los valores de CI50 fueron desde 105 µg mL-1 (Fusarium spp.) hasta 409 µg mL-1 (M. phaseolina). La formación de esclerocios fue completamente inhibida a 500 µg mL-1. Los resultados del presente estudio representan el primer reporte de la acción fungicida/fungistática in vitro del Phi contra los hongos agentes causales de PRYT en el cultivo de soja.Soybean root and stem rots caused by soil-borne pathogens are diseases commonly found in soybean fields, and one of the most important causes of crop losses. In the present study, the mycelial sensitivity of Fusarium virguliforme, F. tucumaniae, Sclerotinia sclerotiorum and Macrophomina phaseolina was evaluated on potato dextrose agar media (25 mL) supplemented with different concentrations of manganese phosphite (MnPhi) diluted in water (0, 25, 37.5, 50, 100, 200, 300, 400, 500, 800 and 1000 µg/mL). Mycelial growth sensitivity was analyzed using logarithmic linear regression analysis. The MnPhi concentration needed to inhibit 50% of the mycelial growth (IC50) ranged from 105 µg/mL (Fusarium spp.) to 409 µg/mL (M. phaseolina). Sclerotia were completely inhibited at 500 µg/mL. The results of our study represent the first report on the direct in vitro fungicidal/fungistatic action of MnPhi against fungi that are causal agents of soil-borne diseases.Fil: Carmona, Marcelo Anibal. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología; ArgentinaFil: Simonetti, Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones en Biociencias Agrícolas y Ambientales; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Biología Aplicada y Alimentos. Cátedra de Microbiología Agrícola; ArgentinaFil: Ravotti, M. E.. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología; ArgentinaFil: Scandiani, María Mercedes. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Luque, A. G.. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Formento, N. A.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Entre Ríos. Estación Experimental Agropecuaria Paraná; ArgentinaFil: Sautua, Francisco. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal. Cátedra de Fitopatología; Argentin

Synthetic bone grafting in aseptic loosening of acetabular cup: Good clinical and radiological outcomes in contained bone defects at mediumterm follow up

Restoring bone loss is one of the major challenges when facing hip revision surgery. To eliminate the risk of disease transmission and antigenicity of allografts and donor-morbidity of autografts, the use of synthetic bioceramics has become popular in the last decade. Our study investigated the effectiveness of impaction bone grafting (IBG) of contained acetabular defects (Paprosky 2 and 3a) using a porous ceramic-based hydroxyapatite bone substitute (Engipore, provided by Finceramica Faenza S.p.A., Faenza, Italy) mixed with a low percentage of autologous bone (obtained from reaming when available). We retrospectively assessed 36 patients who underwent acetabular revision using IBG using a porous ceramic-based hydroxyapatite bone substitute with cementless implants with a mean follow-up of 4.4 years. We evaluated, at regular intervals, patients clinically (using the Hip Harris Score and Oxford Score) and radiologically to evaluate the rate of incorporation of the graft, the presence of radiolucent lines or migrations of the cup. Clinical scores significantly improved (WOMAC improved from 49.7–67.30, and the HSS from 56–89). The rate of implants’ survival was 100% at our medium follow-up (4.4 years). We reported five cases of minor migration of the cup, and radiolucent lines were visible in seven patients at the last-follow up. The graft was well-incorporated in all patients. The results presented in this study suggest the HA bone substitute is an effective and safe bone graft when facing hip revision surgery; thus, longer follow-up studies are required

Renal sympathetic nerve ablation for the treatment of difficult-to-control or refractory hypertension in a haemodialysis patient.

Haemodialysis patients show sympathetic hyperactivity. Hyperactivation of the sympathetic nervous system aggravates hypertension and it is related to left ventricular hypertrophy, heart failure, arrhythmias and atherogenesis. We report the first use of renal sympathetic nerve ablation for correction of uncontrolled hypertension in an end-stage renal disease patient on maintenance dialysis. We observed a progressive and sustained reduction of systemic blood pressure. Our case demonstrates the safety, the feasibility and the efficacy of this procedure. These findings suggest, however, that further clinical trials are needed into renal nerve radiofrequency ablation therapy for the treatment of hypertension and for the improvement of cardiovascular prognosis in this high-risk patient group

Role of interventional radiology in pudendal neuralgia: A description of techniques and review of the literature [Ruolo della radiologia interventistica nella nevralgia del nervo pudendo: Descrizione della tecnica e revisione della letteratura]

Purpose: The authors sought to evaluate indications, technical feasibility and clinical efficacy of computed tomography (CT)-guided pudendal nerve infiltration in patients with chronic anoperineal pain by reviewing the role of the CT technique in their personal experience and in the recent interventional literature. Materials and methods: Twenty-eight women, mean age 50 years, and with a diagnosis of pudendal neuralgia on the basis of clinical and electromyographic criteria were enrolled in the study. CT-guided pudendal nerve injections were performed during three consecutive sessions held 2 weeks apart. In each session, patients received two percutaneous injections: one in the ischial spine, and the other in the pudendal (Alcock's) canal. Results: One patient dropped out of the study after the first session. At clinical assessment, 24h h after treatment, 21/27 patients reported significant pain relief. At follow-up at 3, 6, 9 and 12 months, 24/27 patients reported a ≥ 20% improvement in the Quality of Life (QOL) index. Conclusions. In pudendal nerve entrapment, CT-guided perineural injection in the anatomical sites of nerve impingement is a safe and reproducible treatment with a clinical efficacy of 92% at 12 months. © 2009 Springer-Verlag Italia

Dynamical transitions in the evolution of learning algorithms by selection

We study the evolution of artificial learning systems by means of selection. Genetic programming is used to generate a sequence of populations of algorithms which can be used by neural networks for supervised learning of a rule that generates examples. In opposition to concentrating on final results, which would be the natural aim while designing good learning algorithms, we study the evolution process and pay particular attention to the temporal order of appearance of functional structures responsible for the improvements in the learning process, as measured by the generalization capabilities of the resulting algorithms. The effect of such appearances can be described as dynamical phase transitions. The concepts of phenotypic and genotypic entropies, which serve to describe the distribution of fitness in the population and the distribution of symbols respectively, are used to monitor the dynamics. In different runs the phase transitions might be present or not, with the system finding out good solutions, or staying in poor regions of algorithm space. Whenever phase transitions occur, the sequence of appearances are the same. We identify combinations of variables and operators which are useful in measuring experience or performance in rule extraction and can thus implement useful annealing of the learning schedule.Comment: 11 pages, 11 figures, 2 table

XMM-Newton monitoring of X-ray variability in the quasar PKS 0558-504

We present the temporal analysis of X-ray observations of the radio-loud Narrow-Line Seyfert 1 galaxy (NLS1) PKS 0558-504 obtained during the XMM-Newton Calibration and Performance Verification (Cal/PV) phase. The long term light curve is characterized by persistent variability with a clear tendency for the X-ray continuum to harden when the count rate increases. Another strong correlation on long time scales has been found between the variability in the hard band and the total flux. On shorter time scales the most relevant result is the presence of smooth modulations, with characteristic time of ~ 2 hours observed in each individual observation. The short term spectral variability turns out to be rather complex but can be described by a well defined pattern in the hardness ratio-count rate plane.Comment: 6 pages, 7 figures, accepted for publication in A&A special issue on first results from XM

Context-dependent plant traits drive fine-scale species persistence in old-growth forests

Questions: we studied old growth beech forest vegetation in Permanent Monitoring Plots (PMPs) located in Italy, with the following questions: is species turnover the main component of the observed changes or the present species assemblages is an impoverished sub-sets of the former ones?; 2) how compositional changes are reflected by specific plant functional traits? Location: we selected 4 PMPs (50 x 50 m) of the CONECOFOR network, placed along a latitudinal and climatic gradient in Italy, from south to north: CALABRIA03, CAMPANIA04, ABRUZZO01 and VENETO20. Methods: presence/absence of herb layer species were recorded in 100 permanent micro-plots of 50 x 50 cm over 12 years (1999-2011). For all sampled species we chose a set of 8 easy-to-measure functional traits. We compared the persistence, nestedness and turnover components of compositional changes. The role of plant traits explaining species persistence were analyzed by classification and regression tree. Results: Analysis in species diversity reveal antithetical ecological phenomena due to the diversity and complexity of the 4 different forest stands. ABRUZZO01 and CALABRIA03 show a clear nestedness trends over time with persistent species in ABR01 having higher seed mass and persistent species in CALABRIA03 having scleromorphic leaves and mesoporphic leaves, with large below-ground budbank. On the other hand, VENETO20 and CAMPANIA04 exibit a significant turnover trends over the 12 years characterized by persistent species in VENETO20 having helomorphic leaves, while in CAMPANIA04 large below-ground budbank and smaller SLA were the most important traits for species survival. Conclusion: Fine-scale approach highlight different mechanisms for the maintenance of species diversity in different complex forest systems driven significantly by specific traits, influenced by context-dependent factors