[Antibiotic stewardship programs in the Spanish emergency services: PROA-URG Study]. / Programas de optimización del uso de antimicrobianos en los servicios de urgencias españoles: Estudio PROA-URG.

OBJECTIVE: Antimicrobial stewardship programs (ASP) have become a key tool in the adaptation of these drugs to the health system. The information available on the application and indicators used in these programs in emergency departments is scarce. The objective of this study is to know the extent of ASP implementation in the emergency departments, as well as the use of antimicrobials in these units. METHODS: Multicenter retrospective study. An invitation was sent to all participants of the REDFASTER-SEFH emergency pharmacist working group. A questionnaire was used consisting of 21 items, answered by a team made up of a pharmacist, emergency room specialist, infectious disease specialist and microbiologist. RESULTS: Eighteen hospitals completed the survey. Fourteen (77.8%) had an ASP manager. The DDD value per 1000 admissions ranged between 36.5 and 400.5 (median: 100.4 [IQR:57.2-157.3]). Both carbapenem and macrolide group presented wide variability in use. Six (33.3%) hospitals had an annual report on the specific resistance profile for urine and blood cultures. The percentage of multi-drug resistant strains in urine cultures was 12.5% and in blood cultures 12.2%. The percentage of adequacy in the bacteremia treatment was 81.0% (IQR:74.6-85.0%), while in urinary tract infections was 78.0% (IQR:71.5-88.0). CONCLUSIONS: Despite the existence of ASP members in emergency services, as well as the training activity and local guidelines is common. knowledge of the use of antimicrobials and resistances is limited. Future activities must be aimed at improving information about the ASP results in these units.

A proof-of-concept of cross-luminescent metascintillators: testing results on a BGO:BaF2metapixel.

Objective: Time-of-flight positron emission tomography (PET) is the next frontier in improving the effective sensitivity. To achieve superior timing for time-of-flight PET, combined with high detection efficiency and cost-effectiveness, we have studied the applicability of BaF2 in metascintillators driven by the timing of cross-luminescence photon production.Approach: Based on previous simulation studies of energy sharing and analytic multi-exponential scintillation pulse, as well as sensitivity characteristics, we have experimentally tested a pixel of 3 × 3 × 15 mm3 based on 300µm BGO and 300µm BaF2 layers. To harness the deep ultraviolet cross-luminescent light component, which carries improved timing, we use the FBK VUV SiPM. Metascintillator energy sharing is addressed through a double integration approach.Main results: We reach an energy resolution of 22%, comparable to an 18% resolution of simple BGO pixels using the same readout, through the optimized use of the integrals of the metascintillator pulse in energy sharing calculation. We measure the energy sharing extent of each pulse with a resolution of 25% and demonstrate that experimental and simulation results agree well. Based on the energy sharing, a timewalk correction is applied, exhibiting significant improvements for both the coincidence time resolution (CTR) and the shape of the timing histogram. We reach 242 ps CTR for the entire photopeak, while for a subset of 13% of the most shared events, the CTR value improves to 108 ps, comparable to the 3 × 3 × 5 mm3 LYSO:Ce:Ca reference crystal.Significance: While we are considering different ways to improve further these results, this proof-of-concept demonstrates the applicability of cross-luminescence for metascintillator designs through the application of VUV compatible SiPM coupling, and easily implementable digital algorithms. This is the first test of BaF2-based metascintillators of sufficient stoppng power to be included in a PET scanner, demonstrating the industrial applicability of such cross-luminescent metascintillators.

Position estimation using neural networks in semi-monolithic PET detectors.

Objective. The goal of this work is to experimentally compare the 3D spatial and energy resolution of a semi-monolithic detector suitable for total-body positron emission tomography (TB-PET) scanners using different surface crystal treatments and silicon photomultiplier (SiPM) models.Approach. An array of 1 × 8 lutetium yttrium oxyorthosilicate (LYSO) slabs of 25.8 × 3.1 × 20 mm3separated with Enhanced Specular Reflector (ESR) was coupled to an array of 8 × 8 SiPMs. Three different treatments for the crystal were evaluated: ESR + RR + B,with lateral faces black (B) painted and a retroreflector (RR) layer added to the top face; ESR +RR, with lateral faces covered with ESR and a RR layer on the top face and; All ESR, with lateral and top sides with ESR. Additionally, two SiPM array models from Hamamatsu Photonics belonging to the series S13361-3050AE-08 (S13) and S14161-3050AS-08 (S14) have been compared. Coincidence data was experimentally acquired using a22Na point source, a pinhole collimator, a reference detector and moving the detector under study in 1 mm steps in thex- andDOI- directions. The spatial performance was evaluated by implementing a neural network (NN) technique for the impact position estimation in thex- (monolithic) andDOIdirections.Results. Energy resolution values of 16 ± 1%, 11 ± 1%, 16 ± 1%, 15 ± 1%, and 13 ± 1% were obtained for theS13-ESR + B + RR,S13-AllESR,S14-ESR + B + RR,S14-ESR + RR,andS14-AllESR, respectively. Regarding positioning accuracy, mean average error of 1.1 ± 0.5, 1.3 ± 0.5 and 1.3 ± 0.5 were estimated for thex- direction and 1.7 ± 0.8, 2.0 ± 0.9 and 2.2 ± 1.0 for theDOI- direction, for the ESR + B + RR, ESR + RR and All ESR cases, respectively, regardless of the SiPM model.Significance. Overall, the obtained results show that the proposed semi-monolithic detectors are good candidates for building TB-PET scanners.

Pre-induction cervical ripening with different initial doses of intravaginal misoprostol: time to delivery and peri-natal outcomes.

From 2016 to 2018, a total of 300 pregnant women underwent induction of labour. Those women were allocated in two groups according to the initial dose of misoprostol. Group I (150 women) received intravaginally 50 µg misoprostol followed by 25 µg every four hours, up to a maximum of four doses whereas in group II (150 women) the initial dose was 25 µg intravaginal followed by the same dose every four hours up to a maximum of four doses. Women with previous uterine scar, abnormal foetal heart rate, severe foetal malformation, foetal growth restriction or multiple pregnancy were excluded. The aim of study was to compare the effectiveness (hours until delivery) and perinatal outcomes of both schemes of cervical ripening. Initial doses of 50 µg of misoprostol reduced the time until delivery (17.65 ± 8.2 hours vs. 20.85 ± 9.3 hours; p=.007) and the need of oxytocin (34.6% vs. 46.67%; p=.046), compared to the use of 25 µg misoprostol in all doses. No differences were observed regarding perinatal outcomes.In conclusion, starting with 50 µg of misoprostol in the first dose reduced time to vaginal delivery and decreased the use of oxytocin without worse perinatal outcomes.Impact StatementWhat is already known on this subject? The rate of labour induction is increasing. Mechanical and medical methods try to establish the active phase of labour as quickly and safely as possible. For this reason, there are numerous studies assessing different protocols, dosages and indications.What do the results of this study add? Despite the numerous studies, due to ethical restrictions, it is difficult to carry out prospective studies. For this reason, studies like this help to establish the most appropriate dose of misoprostol in two of the most common indications for induction of labour. We demonstrated that increasing initial doses up to 50 mg of misoprostol are safer and more effective.What are the implications of these findings for clinical practice and/or further research? This study could be useful for future prospective and randomised studies as well for including these data in a meta-analysis. In addition, these results may update the clinical protocols and reduce hospital stay without worse perinatal outcomes.

Vaginal birth after caesarean section before and during COVID-19 pandemic. Factors associated with successful vaginal birth.

BACKGROUND: The ratio of caesarean has been increasing considerably in many countries. Planning a vaginal birth after a previous caesarean is considered an important option for women in a subsequent pregnancy. AIMS: To analyse obstetric and neonatal outcomes in women in labour after caesarean section before and during the COVID-19 pandemic, and to determine factors associated with successful vaginal birth after caesarean (VBAC). METHODS: Observational cohort study of women in labour with history of caesarean section who gave birth between March 2019 and December 2020 in a tertiary hospital in southern Spain. Consecutive sampling was performed using the maternal birth database and a descriptive and inferential analysis of the study variables was carried out. Socio-demographic, obstetric and neonatal variables were compared between the pre-pandemic and pandemic periods. Multiple logistic regression analysis was performed to determine variables associated with VBAC success. FINDINGS: The VBAC success rate was 67.4%. The caesarean section rate was significantly higher during the COVID-19 pandemic period. Factors associated with VBAC success were: birth before the pandemic (OR 0.32) and at night (OR 0.45), use of epidural analgesia (OR 2.14), and having had a previous vaginal birth (OR 1.98). CONCLUSIONS: The success rate of VBAC was lower during the pandemic. Knowledge of the factors related to VBAC success is critical for practitioners when supporting women in decision-making about mode of birth after a previous caesarean section.

[Temporal pole encephalocele, a surgical treatable cause of drug-resistant epilepsy]. / Encefalocele del polo temporal: una causa tratable quirúrgicamente de epilepsia farmacorresistente.

INTRODUCTION: Encephaloceles are herniation of brain parenchyma through a bony skull defect that can cause drug-resistant epilepsy. In these cases, a surgical approach should be considered. CASE REPORT: 38-year-old man with drug-resistant epilepsy and 1.5 T magnetic resonance imaging performed with no relevant findings. After video-electroencephalogram, 3 T magnetic resonance imaging and F-18-fluoro-deoxy-glucose positron emission tomography, a right temporal encephalocele was confirmed. A right temporal polar resection was performed four years ago and the patient remains seizure-free. DISCUSSION: Anterior temporal encephaloceles are an underdiagnosed cause of epilepsy, and a 3 T magnetic resonance imaging reviewed by an epilepsy expert radiologists is key to diagnosis. CONCLUSION: In drug-resistant cases with presurgical evaluation compatible with the location, surgical treatment must be considered.

TITLE: Encefalocele del polo temporal: una causa tratable quirúrgicamente de epilepsia farmacorresistente.Introducción. Los encefaloceles son herniaciones del parénquima cerebral consecuencia de un defecto óseo. Si producen epilepsia farmacorresistente, hay que plantearse un abordaje quirúrgico. Caso clínico. Varón de 38 años con epilepsia farmacorresistente y estudio estándar de resonancia magnética de 1,5 T sin hallazgos. Tras realizar un videoelectroencefalograma, una resonancia magnética de 3 T y una tomografía por emisión de positrones con fluorodesoxiglucosa, se confirmó la presencia de un encefalocele del polo temporal derecho. Se efectuó una resección de ese polo temporal y cuatro años después el paciente continúa libre de crisis. Discusión. Los encefaloceles temporales anteriores constituyen una causa infradiagnosticada de epilepsia en cuyo estudio es clave la resonancia magnética de 3 T y la evaluación por un radiólogo experimentado en epilepsia. Conclusión. En casos farmacorresistentes y evaluación prequirúrgica de la epilepsia congruente con la localización, hay que considerar su tratamiento quirúrgico.

Spanish multicenter study of surgical resection of pancreatic tumors infiltrating the celiac axis: does the type of pancreatectomy affect results?

BACKGROUND: Pancreatectomy plus celiac axis resection (CAR) is performed in patients with locally advanced pancreatic cancer. The morbidity rates are high, and no survival benefit has been confirmed. It is not known at present whether it is the type of pancreatectomy, or CAR itself, that is the reason for the high complication rates. METHODS: Observational retrospective multicenter study. INCLUSION CRITERIA: patient undergoing TP, PD or DP plus CAR for a pancreatic cancer. RESULTS: Sixty-two patients who had undergone pancreatic cancer surgery (PD,TP or DP) plus CAR were studied. Group 1: 17 patients who underwent PD/TP-CAR (13TP/4PD); group 2: 45 patients who underwent DP-CAR. Groups were mostly homogeneous. Operating time was longer in the PD/TP group, while operative complications did not differ statistically in the two groups. The number of lymph nodes removed was higher in the PD/TP group (26.5 vs 17.3), and this group also had a higher positive node ratio (17.9% vs 7.6%). There were no statistical differences in total or disease-free survival between the two groups. CONCLUSION: It seems that CAR, and not the type of pancreatectomy, influences morbidity and mortality in this type of surgery. International multicenter studies with larger numbers of patients are now needed to validate the data presented here.

Prevalence of overweight and obesity in a Mexican prison.

OBJECTIVES: Overweight and obesity constitute a public health problem; There are few prevalence studies of inmates. The objectives of this study are to determine the prevalence of overweight and obesity amongst inmates of the Islas Marias Prison Complex and to evaluate the waist-to-hip ratio (WHR) and the waist-to-height ratio (WHtR) as diagnostic measurements for abdominal obesity in this population. MATERIAL AND METHOD: Analytical, retrospective cross-sectional study at Rural Hospital No. 20 Islas Marias Nayarit, Mexico, with 426 cases from January 2016 to March 2017, who were male inmates from 18 to 73 years of age. The following ratios were calculated: BMI, WHR WHtR. A descriptive analysis was carried out for quantitative variables, frequencies and percentages by group, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), Youden index, positive and negative likelihood ratios of WHR and WHtR; ANOVA F test, Student's t-test, ROC curve, STROBE statement, SPSS v. 22. RESULTS: 51.41% cases presented as overweight, 25.35% were obese, the cut-off point was 0.935 for WHR (s = 0.833; e = 0.717) and 0.545 for WHtR ICA (s = 0.981; e = 0.818). WHtR showed a good performance according to the Youden index. DISCUSSION: There was a high prevalence of overweight and obesity in prisoners at the Islas Marias Prison Complex, WHtR showed better performance than WHR for diagnosing abdominal obesity. It is suggested that measurement of WHI should be included in daily medical practice.

Ensemble of neural networks for 3D position estimation in monolithic PET detectors.

We propose an ensemble of multilayer feedforward neural networks to estimate the 3D position of photoelectric interactions in monolithic detectors. The ensemble is trained with data generated from optical Monte Carlo simulations only. The originality of our approach is to exploit simulations to obtain reference data, in combination with a variability reduction that the network ensembles offer, thus, removing the need of extensive per-detector calibration measurements. This procedure delivers an ensemble valid for any detector of the same design. We show the capability of the ensemble to solve the 3D positioning problem through testing four different detector designs with Monte Carlo data, measurements from physical detectors and reconstructed images from the MindView scanner. Network ensembles allow the detector to achieve a 2-2.4 mm FWHM, depending on its design, and the associated reconstructed images present improved SNR, CNR and SSIM when compared to those based on the MindView built-in positioning algorithm.

Arbuscular mycorrhizal fungi inoculation mediated changes in rhizosphere bacterial community structure while promoting revegetation in a semiarid ecosystem.

The main goal of this study was to assess the effect of the inoculation of four autochthonous shrub species with the arbuscular mycorrhizal (AM) fungus Rhizophagus intraradices on the rhizosphere bacterial community and to ascertain whether such an effect is dependent on the host plant species. Additionally, analysis of rhizosphere soil chemical and biochemical properties was performed to find relationships between them and the rhizosphere bacterial communities. Non-metric multidimensional scaling analysis and subsequent permutational multivariate analysis of variance revealed differences in bacterial community composition and structure between non-inoculated and inoculated rhizospheres. Moreover, an influence of the plant species was observed. Different bacterial groups were found to be indicator taxonomic groups of non-inoculated and inoculated rhizospheres, Gemmatimonadetes and Anaerolineaceae, respectively, being the most notable indicators. As shown by distance based redundancy analysis, the shifts in bacterial community composition and structure mediated by the inoculation with the AM fungus were mainly related to changes in plant nutrients and growth parameters, such as the shoot phosphorus content. Our findings suggest that the AM fungal inoculum was able to modify the rhizosphere bacterial community assemblage while improving the host plant performance.

Pseudomonas syringae pv. phaseolicola isolated from weeds in bean crop fields.

UNLABELLED: Pseudomonas syringae pv. phaseolicola, the causative agent of halo blight in common bean (Phaseolus vulgaris L.), was isolated from weeds associated with bean crops in Spain. The bacterium was recovered from Fumaria sp, Mercurialis annua, Solanum nigrum and Sonchus oleraceus. Ps. s. pv. phaseolicola had previously been isolated from leguminous plants and S. nigrum, but to our knowledge, this is the first time it was recovered from the other three species. The isolates were phenotypically and genetically characterized, and they were compared with isolates recovered from common beans. Five different genotypic profiles were detected by PmeI-PFGE, two of them being of new description. Weed isolates were as pathogenic on bean plants as bean isolates, but they were not pathogenic on S. nigrum. Regarding the survival of the pathogen in weeds, Ps. s. pv. phaseolicola was isolated from So. oleraceus 11 weeks after the end of the bean crop. These results strongly support the idea of weeds as a potential source of inoculum for halo blight in bean. SIGNIFICANCE AND IMPACT OF THE STUDY: It has traditionally been considered that the main source of inoculum of Pseudomonas syringae pv. phaseolicola causing halo blight disease in Phaseolus vulgaris are the bean seeds, and that the host range of the bacterium is almost restricted to leguminous plants. In this study, the bacterium was recovered from four nonleguminous weed species collected in bean fields, and its permanence in weeds for at least 11 weeks after the harvesting of the beans was demonstrated. We have also proved that the strains isolated from weeds were pathogenic on bean plants. Accordingly, the host range of Ps. s. pv. phaseolicola could be broader than previously thought and weeds appear to be acting as a reservoir of the pathogen until the next crop.

Cytotoxic activity of hirsutanone, a diarylheptanoid isolated from Alnus glutinosa leaves.

BACKGROUND: The low efficacy of cancer therapy for the treatment of patients with advanced disease makes the development of new anticancer agents necessary. Because natural products are a significant source of anticancer drugs, it is important to explore cytotoxic activity of novel compounds from natural origin. PURPOSE: The aim of this work is to evaluate the cytotoxic capacity of hirsutanone, a diarylheptanoid isolated from Alnus glutinosa leaves. Hirsutanone cytotoxic way of action was also studied. MATERIAL AND METHODS: The cytotoxic ability of Alnus glutinosa leaves ethyl acetate extract was studied over HeLa and PC-3 cell lines, with the MTT colorimetric assay. Hirsutanone was isolated from this extract using chromatographic methods, and its structure elucidated by spectroscopic analysis. HT-29 cell viability after hirsutanone treatment was determined using SRB assay. In order to understand hirsutanone way of action, cytotoxicity was evaluated adding the diarylheptanoid and antioxidants. DNA topoisomerase II (topo II) poison activity, was also evaluated using purified topo II and a supercoiled form of DNA that bears specific topo II recognition and binding region; topo II poisons stabilize normally transient DNA-topo II cleavage complexes, and lead an increased yield of linear form as a consequence of a lack of double-strand breaks rejoining. RESULTS: The diarylheptanoid hirsutanone was isolated from Alnus glutinosa (L.) Gaertn. (Betulaceae) leaves extract that showed cytotoxic activity against PC-3 and HeLa cell lines. Hirsutanone showed cytotoxic activity against HT-29 human colon carcinoma cells. Pre-treatment with the antioxidants NAC (N-acetylcysteine) and MnTMPyP (Mn(III)tetrakis-(1-methyl-4-pyridyl)porthyrin) reduced this activity, suggesting that reactive oxygen species (ROS) participate in hirsutanone-induced cancer cell death. Using human topo II and a DNA supercoiled form, hirsutanone was found to stabilize topo II-DNA cleavage complexes, acting as a topo II poison. CONCLUSION: Our data suggest that, like curcumin, an induction of oxidative stress and topo II-mediated DNA damage may play a role in hirsutanone-induced cancer cell death. Since both compounds share similar structure and cytotoxic profile, and curcumin is in clinical trials for the treatment of cancer, our results warrant further studies to evaluate the anticancer potential of hirsutanone.

Magnetic nanoparticles: new players in antimicrobial peptide therapeutics.

Antimicrobial peptides are distributed in all forms of life presenting activity against bacteria, fungi, viruses, parasites and cancer. In spite of the tremendous potential of these molecules, very few of them have been successfully developed into therapeutics. The major problems associated with this new class of antimicrobials are molecule stability, toxicity in host cells and production cost. A novel strategy to overcome these obstacles is conjugation to nanomaterials. Magnetic nanoparticles have been widely studied in biomedicine due to their physicochemical properties. The conjugation of antimicrobial peptides to magnetic nanoparticles could combine the best properties of both, generating an improved antimicrobial nanoparticle. Here we provide an overview and discuss the potential application of magnetic nanoparticles conjugated to antimicrobial peptides in overcoming diseases.

Expectation maximization (EM) algorithms using polar symmetries for computed tomography (CT) image reconstruction.

We suggest a symmetric-polar pixellation scheme which makes possible a reduction of the computational cost for expectation maximization (EM) iterative algorithms. The proposed symmetric-polar pixellation allows us to deal with 3D images as a whole problem without dividing the 3D problem into 2D slices approach. Performance evaluation of each approach in terms of stability and image quality is presented. Exhaustive comparisons between all approaches were conducted in a 2D based image reconstruction model. From these 2D approaches, that showing the best performances were finally implemented and evaluated in a 3D based image reconstruction model. Comparison to 3D images reconstructed with FBP is also presented. Although the algorithm is presented in the context of computed tomography (CT) image reconstruction, it can be applied to any other tomographic technique as well, due to the fact that the only requirement is a scanning geometry involving measurements of an object under different projection angles. Real data have been acquired with a small animal (CT) scanner to verify the proposed mathematical description of the CT system.

Design and evaluation of the MAMMI dedicated breast PET.

PURPOSE: A breast dedicated positron emission tomography (PET) scanner has been developed based on monolithic LYSO crystals coupled to position sensitive photomultiplier tubes (PSPMTs). In this study, we describe the design of the PET system and report on its performance evaluation. METHODS: MAMMI is a breast PET scanner based on monolithic LYSO crystals. It consists of 12 compact modules with a transaxial field of view (FOV) of 170 mm in diameter and 40 mm axial FOV that translates to cover up to 170 mm. The patient lies down in a prone position that facilitates maximum breast elongation. Quantitative performance analysis of the calculated method for the attenuation correction specifically developed for MAMMI, and based on PET image segmentation, has also been conducted in this evaluation. In order to fully determine the MAMMI prototype's performance, we have adapted the measurements suggested for National Electrical Manufacturers Association (NEMA) NU 2-2007 and NU 4-2008 protocol tests, as they are defined for whole-body and small animal PET scanners, respectively. RESULTS: Spatial resolutions of 1.6, 1.8, and 1.9 mm were measured in the axial, radial, and tangential directions, respectively. A scatter fraction of 20.8% was obtained and the maximum NEC was determined to be 25 kcps at 44 MBq. The average sensitivity of the system was observed to be 1% for an energy window of (250 keV-750 keV) and a maximum absolute sensitivity of 1.8% was measured at the FOV center. CONCLUSIONS: The overall performance of the MAMMI reported on this evaluation quantifies its ability to produce high quality PET images. Spatial resolution values below 3 mm were measured in most of the FOV. Only the radial component of spatial resolution exceeds the 3 mm at radial positions larger than 60 mm. This study emphasizes the need for standardized testing methodologies for dedicated breast PET systems similar to NEMA standards for whole-body and small animal PET scanners.

First Report of Cobweb on White Button Mushroom (Agaricus bisporus) in Spain Caused by Cladobotryum mycophilum.

Between 2008 and 2011, symptoms of cobweb were observed in commercial white button mushroom (Agaricus bisporus) crops in Castilla-La Mancha (Spain). Typical symptoms started as white, cobweb-like mycelial growth over the surface of the casing soils and fruiting bodies. Later, the mycelium changed to a grayish white, dense powder and the affected fruiting bodies turned pale yellow or reddish brown before rotting. Two types of cap spotting were observed, dark brown spots with a poorly defined edge and light brown spots. The first symptoms were commonly seen in the second or third break (flush) of mushrooms. Infected tissues of A. bisporus were plated onto potato dextrose agar (PDA) and a parasitic fungus was isolated. Fungal colonies consisted of abundant, cottony, aerial mycelium spreading rapidly over the PDA, and red pigment spreading into the agar. The cultures lacked a camphor odor. Conidiogenous cells were 24 to 45 µm long, 3 to 6 µm wide basally, and tapered slightly to the tip. Conidia were cylindrical to narrowly ellipsoidal, 15 to 28 × 8 to 11 µm, and zero- to three-septate. Total DNA was extracted and the internal transcribed spacer (ITS) region of rDNA amplified for one mycelial isolate using ITS1F/ITS4 primers (2,4). The amplicon was sequenced (GenBank Accession No. JQ004732). BLAST analysis showed highest similarity (99 and 100%) of the ITS sequence to four ITS sequences of Cladobotryum mycophilum (teleomorph Hypomyces odoratus) (GenBank Accession Nos. AB527074, JF505112, Y17095, and Y17096) (1,3) among other sequences of the same species. Two pathogenicity trials (A and B) were performed in mushroom-growing rooms, with 24 blocks in each assay containing pasteurized, spawned, and incubated A. bisporus substrate (10 kg, 0.15 m2). The blocks were cased with a 35-mm layer of a peat-based casing soil (5.5 liter/block). Nine days after casing, a conidial suspension (7.5 × 103 conidia/ml) of one isolate of C. mycophilum was sprayed (20 ml/block) onto the surface of the casing layer of 12 blocks at 106 conidia/m2. Twelve blocks were sprayed with sterile distilled water as a control treatment. Blocks were maintained at 17.5°C and 90% relative humidity. The first cobweb symptoms developed 25 days after inoculation, between the second and third breaks in trial A; and after 11 days, between the first and second breaks in trial B. C. mycophilum was consistently reisolated from eight inoculated blocks (67%) in trial A, and 11 inoculated blocks (92%) in trial B. The total area of the crop affected by cobweb was 30% in inoculated blocks in trial A and 45% in trial B. The noninoculated blocks remained healthy. Compared with the noninoculated control blocks, a 10.7% decrease in yield of mushrooms was observed in trial A and 9.1% in trial B. Previously, C. dendroides was the only known causal agent of cobweb in Spain. To our knowledge, this is the first report of C. mycophilum causing cobweb in white button mushroom in Spain, although the disease and causal agent were previously reported on cultivated king oyster mushroom (Pleurotus eryngii) in Spain (3). References: (3) C.-G. Back et al. J. Gen. Plant Pathol. 76:232, 2010. (1) M. Gardes and T. D. Bruns. Mol. Ecol. 2:113, 1993. (4) F. J. Gea et al. Plant Dis. 95:1030, 2011. (2) T. J. White et al. PCR Protocols. A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.

Effect of cation disorder on structural, magnetic and dielectric properties of La2MnCoO6 double perovskite.

The origin of dielectric anomalies and magnetodielectric response of La(2)MnCoO(6) has been investigated by means of ultra-high resolution synchrotron x-ray powder diffraction, neutron powder diffraction, resistivity, magnetization and dielectric measurements. The study has been performed on two different bulk samples presenting different degrees of Mn/Co order: 95 and 74%. Beside the well-known influence on magnetic properties, our results show that the main effect of disorder lies on the electrical resistivity. Bond distances clearly show Mn(4+)/Co(2+) valence states in the well-ordered sample, while for the disordered one this picture still holds. AC resistivity data show dielectric anomalies and a small magnetodielectric effect, but impedance complex plane analyses prove that these phenomena appear at the frequency-temperature region where extrinsic effects dominate the dielectric response.

Brown Blotch Caused by Pseudomonas tolaasii on Cultivated Pleurotus eryngii in Spain.

In 2006, symptoms of brown blotch were observed on cultivated Pleurotus eryngii (king oyster mushroom) in Castilla-La Mancha (Spain). Subsequently, between January and May of 2008, brown blotch affected 39.75% of the blocks of substrate cultivated, resulting in a considerable loss of production. Symptoms observed were principally characterized by a yellowish brown-to-orangish color, first of the cap and then of the stalk. Some samples also showed a slightly concave cap. From samples collected from four different king oyster mushroom farms, a fluorescent gram-negative bacterium was recovered on King's B medium and identified as Pseudomonas tolaasii by the LOPAT scheme and other tests (2). The bacterium isolated had the following characteristics: oxidative, positive for oxidase and arginine dihydrolase, negative for levan production, pectinolitic activity on potato slices, and tobacco hypersensitivity. Results from other tests were as follows: negative for esculin hydrolysis and positive for gelatine, casein, and Tween 80 hydrolysis; mannitol, erythritol, sorbitol, m-inositol, and adonitol were used as a sole carbon source, but not sucrose, d-tartrate, or trigonelline. The white line test was performed (4) using P. reactans LPPA 540 and the presumptive isolates of P. tolaasii were positive. The gene encoding the 16S rRNA from two isolates (LPPA532 and LPPA533) was sequenced after PCR amplification (2) and their nucleotide sequences (1,400 bp; EMBL Accession No. FM864215 for LPPA 532) proved to be identical. The amplified sequences were compared with DNA sequences available in databases (GenBank, EMBL, DDBJ, and PDB) by using BLAST. An identity of 99% was obtained with 16S rDNA of three P. tolaasii strains (GenBank Accession Nos. AF320990, AF094750, and AF255336). Four isolates were selected for pathogenicity tests. Bacterial suspensions were grown for 16 h in yeast peptone glucose broth (approximately 108 CFU/ml) and were inoculated by puncture into 10 mushroom caps using sterilized wooden toothpicks (4). Sterilized distilled water was used as a control. These were then incubated at room temperature in glass dishes. Assays were conducted twice and the results were recorded after 10 days. The symptoms that developed after infection were similar to those observed in the crop, while the control mushrooms remained symptomless. Bacteria sharing the characteristics of the inoculated isolates were recovered from symptomatic caps. P. tolaasii has been described as causing brown blotch on Pleurotus eryngii (1,3), but to our knowledge, this is the first report of P. tolaasii causing brown blotch on Pleurotus eryngii in Spain. References: (1) J. F. Bradbury. No. 891 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1987. (2) A. J. González et al. Appl. Environ. Microbiol. 69:2936, 2003. (3) A. Russo et al. Microbiol. Res. 158:265, 2003. (4) J. M. Wells et al. Phytopathology 86:1098, 1996.