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Bacterial spot caused by Xanthomonas arboricola pv. pruni (Xap) is a major threat to Prunus species worldwide. The molecular mechanisms of peach resistance to Xap during early leaf infection were investigated by RNA-Seq analysis of two Prunus persica cultivars, ‘Redkist’ (resistant), and ‘JH Hale’ (susceptible) at 30 minutes, 1 and 3 hours-post-infection (hpi). Both cultivars exhibited extensive modulation of gene expression at 30 mpi, which reduced significantly at 1 hpi, increasing again at 3 hpi. Overall, 714 differentially expressed genes (DEGs) were detected in ‘Redkist’ (12% at 30 mpi and 1 hpi and 88% at 3 hpi). In ‘JH Hale’, 821 DEGs were identified (47% at 30 mpi and 1 hpi and 53% at 3 hpi). Highly up-regulated genes (fold change > 100) at 3 hpi exhibited higher fold change values in ‘Redkist’ than in ‘JH Hale’. RNA-Seq bioinformatics analyses were validated by RT-qPCR. In both cultivars, DEGs included genes with putative roles in perception, signal transduction, secondary metabolism, and transcription regulation, and there were defense responses in both cultivars, with enrichment for the gene ontology terms, ‘immune system process’, ‘defense response’, and ‘cell death’. There were particular differences between the cultivars in the intensity and kinetics of modulation of expression of genes with putative roles in transcriptional activity, secondary metabolism, photosynthesis, and receptor and signaling processes. Analysis of differential exon usage (DEU) revealed that both cultivars initiated remodeling their transcriptomes at 30 mpi; however, ‘Redkist’ exhibited alternative exon usage for a greater number of genes at every time point compared with ‘JH Hale’. Candidate resistance genes (WRKY-like, CRK-like, Copper amine oxidase-like, and TIR-NBS-LRR-like) are of interest for further functional characterization with the aim of elucidating their role in Prunus spp. resistance to Xap. [ABSTRACT FROM AUTHOR]

Bacterial canker disease caused by Pseudomonas syringae pv. actinidiae, an emerging pathogen of kiwifruit plants, has recently brought about major economic losses worldwide. Genetic studies on virulence functions of P. syringae pv. actinidiae have not yet been reported and there is little experimental data regarding bacterial genes involved in pathogenesis. In this study, we performed a genetic screen in order to identify transposon mutants altered in the lipolytic activity because it is known that mechanisms of regulation, production, and secretion of enzymes often play crucial roles in virulence of plant pathogens. We aimed to identify the set of secretion and global regulatory loci that control lipolytic activity and also play important roles in in planta fitness. Our screen for altered lipolytic activity phenotype identified a total of 58 TnJ transposon mutants. Mapping all these Tn5 mutants revealed that the transposons were inserted in genes that play roles in cell division, chemotaxis, metabolism, movement, recombination, regulation, signal transduction, and transport as well as a few unknown functions. Several of these identified P. syringae pv. actinidiae Tn5 mutants, notably the functions affected in phosphomannomutase AlgC, lipid A biosynthesis acyltransfera.se, glutamate-cysteine ligase, and the type IV pilus protein Pill, were also found affected in in planta survival and/or growth in kiwifruit plants. The results of the genetic screen and identification of novel loci involved in in planta fitness of P. syringae pv. actinidiae are presented and discussed. [ABSTRACT FROM AUTHOR]

The paper provides a contribution for populating database of three physical parameters needed to model energy performance of buildings with green roofs: “coverage ratio” ( σ f ), leaf area index (LAI) and leaf temperature ( T f ). On purpose, six plant species were investigated experimentally: Phyla nordiflora, Aptenia lancifolia , Mesembryanthenum barbatus , Gazania nivea, Gazania uniflora , and Sedum . Proper ranges of the cited parameters have been found for each species. The here indicated ranges of σ f values refer to different growth levels of the species in the same lapse of time, that is four months. Single measured LAI values are also reported for the same plants. As for the T f (upper and lower layer), ranges of revealed temperatures refer to those detected from 10:30 a.m. to 16:30 p.m. of a selected day. Additionally, the dependence of T f on climatic parameters was investigated. A linear equation resulted the best fitting curve for all experimental T f data and the corresponding solar radiation data (with autocorrelation coefficients between 0.80 and 0.98). Furthermore, the effect potentially produced on building energy consumption by these species was analyzed using a simulation tool. Estimated cooling energy savings range approximately between 8% and 20% depending on adopted plants. [ABSTRACT FROM AUTHOR]

A simplified version of the ecological footprint method is proposed for assessing the environmental performances of urban transportation systems. The method, starting from the knowledge of the composition of the running vehicular fleet, is here applied to a southern Italian province. It represents a synthetic indicator of the environmental pressure exerted by the system also matching the pollutant emissions with the carrying capacity of the site. Particularly, the forested area needed to absorb the CO2 emissions of the system is compared with the total forested area of the province. The results of the case-study indicates the yearly maximum distance that each vehicle of the fleet can cover in order for their emissions to be absorbed by the surrounding forested area. Specifically, if all cars of the fleet would travel for 10,000 km/year, 97% of the forested area would be involved. Thanks to its features, this indicator can be usefully adopted for ranking different transportation options. Therefore, it could allow local administrations to environmentally hierarchize alternative plans concerning urban transportation choices. [ABSTRACT FROM AUTHOR]

Pseudomonas syringae pv. actinidiae (Psa) is an emerging phytopathogen causing bacterial canker disease in kiwifruit plants worldwide. Quorum sensing (QS) gene regulation plays important roles in many different bacterial plant pathogens. In this study we analyzed the presence and possible role of N-acyl homoserine lactone (AHL) quorum sensing in Psa. It was established that Psa does not produce AHLs and that a typical complete LuxI/R QS system is absent in Psa strains. Psa however possesses three putative luxR solos designated here as PsaR1, PsaR2 and PsaR3. PsaR2 belongs to the sub-family of LuxR solos present in many plant associated bacteria (PAB) that binds and responds to yet unknown plant signal molecules. PsaR1 and PsaR3 are highly similar to LuxRs which bind AHLs and are part of the canonical LuxI/R AHL QS systems. Mutation in all the three luxR solos of Psa showed reduction of in planta survival and also showed additive effect if more than one solo was inactivated in double mutants. Gene promoter analysis revealed that the three solos are not auto-regulated and investigated their possible role in several bacterial phenotypes. [ABSTRACT FROM AUTHOR]

A recent re-emerging bacterial canker disease incited by Pseudomonas syringae pv. actinidiae (Psa) is causing severe economic losses to Actinidia chinensis and A. deliciosa cultivations in southern Europe, New Zealand, Chile and South Korea. Little is known about the genetic features of this pathovar. We generated genome-wide Illumina sequence data from two Psa strains causing outbreaks of bacterial canker on the A. deliciosa cv. Hayward in Japan (J-Psa, type-strain of the pathovar) and in Italy (I-Psa) in 1984 and 1992, respectively as well as from a Psa strain (I2-Psa) isolated at the beginning of the recent epidemic on A. chinensis cv. Hort16A in Italy. All strains were isolated from typical leaf spot symptoms. The phylogenetic relationships revealed that Psa is more closely related to P. s. pv. theae than to P. avellanae within genomospecies 8. Comparative genomic analyses revealed both relevant intrapathovar variations and putative pathovar-specific genomic regions in Psa. The genomic sequences of J-Psa and I-Psa were very similar. Conversely, the I2-Psa genome encodes four additional effector protein genes, lacks a 50 kb plasmid and the phaseolotoxin gene cluster, argK-tox but has acquired a 160 kb plasmid and putative prophage sequences. Several lines of evidence from the analysis of the genome sequences support the hypothesis that this strain did not evolve from the Psa population that caused the epidemics in 1984-1992 in Japan and Italy but rather is the product of a recent independent evolution of the pathovar actinidiae for infecting Actinidia spp. All Psa strains share the genetic potential for copper resistance, antibiotic detoxification, high affinity iron acquisition and detoxification of nitric oxide of plant origin. Similar to other sequenced phytopathogenic pseudomonads associated with woody plant species, the Psa strains isolated from leaves also display a set of genes involved in the catabolism of plantderived aromatic compounds. [ABSTRACT FROM AUTHOR]

Forty-five Xanthomonas arboricola pv. juglandis (Xaj) strains originating from Juglans regia cultivation in different countries were molecularly typed by means of MultiLocus Sequence Typing (MLST), using acnB, gapA, gyrB and rpoD gene fragments. A total of 2.5 kilobases was used to infer the phylogenetic relationship among the strains and possible recombination events. Haplotype diversity, linkage disequilibrium analysis, selection tests, gene flow estimates and codon adaptation index were also assessed. The dendrograms built by maximum likelihood with concatenated nucleotide and amino acid sequences revealed two major and two minor phylotypes. The same haplotype was found in strains originating from different continents, and different haplotypes were found in strains isolated in the same year from the same location. A recombination breakpoint was detected within the rpoD gene fragment. At the pathovar level, the Xaj populations studied here are clonal and under neutral selection. However, four Xaj strains isolated from walnut fruits with apical necrosis are under diversifying selection, suggesting a possible new adaptation. Gene flow estimates do not support the hypothesis of geographic isolation of the strains, even though the genetic diversity between the strains increases as the geographic distance between them increases. A triplet deletion, causing the absence of valine, was found in the rpoD fragment of all 45 Xaj strains when compared with X. axonopodis pv. citri strain 306. The codon adaptation index was high in all four genes studied, indicating a relevant metabolic activity. [ABSTRACT FROM AUTHOR]

To study the role of type III-secreted effectors in the host adaptation of the tobacco ( Nicotiana sp.) pathogen Pseudomonas syringae pv. tabaci, a selection of seven strains was first characterized by multilocus sequence typing (MLST) to determine their phylogenetic affinity. MLST revealed that all strains represented a tight phylogenetic group and that the most closely related strain with a completely sequenced genome was the bean ( Phaseolus vulgaris) pathogen P. syringae pv. phaseolicola 1448A. Using primers designed to 21 P. syringae pv. phaseolicola 1448A effector genes, it was determined that P. syringae pv. phaseolicola 1448A shared at least 10 effectors with all tested P. syringae pv. tabaci strains. Six of the 11 effectors that failed to amplify from P. syringae pv. tabaci strains were individually expressed in one P. syringae pv. tabaci strain. Although five effectors had no effect on phenotype, growth in planta and disease severity of the transgenic P. syringae pv. tabaci expressing hopQ1-1Pph1448A were significantly increased in bean, but reduced in tobacco. We conclude that hopQ1-1 has been retained in P. syringae pv. phaseolicola 1448A, as this effector suppresses immunity in bean, whereas hopQ1-1 is missing from P. syringae pv. tabaci strains because it triggers defences in Nicotiana spp. This provides evidence that fine-tuning effector repertoires during host adaptation lead to a concomitant reduction in virulence in non-host species. [ABSTRACT FROM AUTHOR]

The European Group for Blood and Marrow Transplantation (EBMT), formerly known as European Group for Bone Marrow Transplantation, was established in 1974 in the Netherlands to share experiences, to promote research and clinical studies and to set up registries in the field of hematopoietic tissue transplantation. At the present time more 400 European and non-European centers are members of the EBMT group. In 1984 a new Working Party was created (Solid Tumors) with the aim to investigate the role of high-dose chemotherapy and stem cell support in the fields of adult and pediatric solid tumors. By January 2000 more than 14 000 patients were registered, and at the present time this Registry is the world largest database on this subject. Several phase III randomized clinical trials have recently started on behalf of the Group in different diseases (breast carcinoma, small cell lung cancer, ovarian carcinoma, germ cell tumors and Ewing''s family sarcoma). Hundreds of randomized patients will finally produce clearer information on this still experimental therapeutic modality. This paper will describe the EBMT Solid Tumors Working Party Registry updated results as well as the main ongoing studies. [Copyright &y& Elsevier]

• Hypothalamic Hamartoma is a rare congenital disease but with great impact on subcortical epilepsy research. • Associated Epilepsy presents with wide variation of clinical spectrum and psychiatric comorbidities. • Clinical presentation is largely affected by fine anatomical patterns and relation with hypothalamus complexes. • Gamma Knife Radiosurgery could treat the different patterns whatever the hypothalamic area involved. Evidence exists for the role of the hypothalamic hamartoma's topography as a determinant for the clinical presentation. How the hamartoma relation to the hypothalamic structures can make clinical presentations, severity and surgery outcomes different from patient to patient is largely unknown. Our aim was to analyze the effect of fine anatomical topography on clinical spectrum and radiosurgery outcome. Forty-eight epileptic patients with hypothalamic hamartoma were treated by Gamma Knife Surgery and were reviewed for fine topography and morphology using magnetic resonance neuroimaging. We evaluated different topographic patterns; contact to prominent structures (the mammillary body, tuber cinereum and pituitary stalk), the degree of involvement within sagittally-oriented regions, (mammillary, tuberal, and supra optic) coronally-oriented zones (periventricular, medial, and lateral), lesion dimensions (length, width, and height),and volumes (total, intra-hypothalamic, and extra-hypothalamic volumes). This data were statistically analysed for correlation with all clinical variables and epilepsy surgery outcome. We reviewed all the classification protocols in the literature. Focal onset impaired awareness seizures started at an earlier age of onset with larger hypothalamic hamartoma volume and dimensions. Lateral extension within the hypothalamus was associated with more severe epilepsy, higher seizure frequency, more severe psychiatric comorbidity, hetero-aggression, hyperkinesia, and school difficulties. Presence of precocious puberty was positively correlated to anterior-posterior extension; tuberal region involvement, hypothalamic hamartoma volume, and type III-VI. Larger hypothalamic hamartoma presented precocious puberty at an earlier age of onset. After Gamma Knife Surgery, epilepsy outcome was better and rapid when lesion is smaller. Post-radiosurgical transient increased seizures were present when the mammillary region was more involved. Clinical presentation of epileptic hypothalamic hamartoma is significantly affected by fine topography patterns and invaded hypothalamic areas. Gamma Knife Radiosurgery effect is better and rapid in smaller hamartoma (Type I-III) and seizure outcome was not affected by the invaded hypothalamic areas. [ABSTRACT FROM AUTHOR]

Strawberry is a very popular fruit, appreciated for its unique flavor and many beneficial traits such as antioxidants and useful amino acids, which strongly contribute to the overall quality of the product. Indeed, the quality of fresh fruit is a fundamental aspect for consumers, and it is crucial for the success of breeding activities as well as for enhancing the competitiveness and profitability of the fruit industry. Nowadays, the entire supply chain requires simple and fast systems for quality evaluation. In this context, the pomological and chemical traits (i.e., soluble solids, firmness, titratable acidity, dry matter) as well as nutritional ones such as total phenols, total anthocyanins and antioxidant potential were evaluated and compared for seven strawberry cultivars and three harvest times. The prediction of the qualitative traits was carried out using color space coordinates (L*, a* and b*) and two statistical techniques, i.e., the multiple linear regression models (MLR) and artificial neural networks (ANNs). Unsatisfactory prediction performances were obtained for all parameters when MLR was applied. On the contrary, the good prediction of the internal quality attributes, using ANN, was observed, especially for both antioxidant activity and the total monomeric anthocyanin (R2 = 0.906, and R2 = 0.943, respectively). This study highlighted that color coordinates coupled with ANN can be successfully used to evaluate the quality of strawberry. [ABSTRACT FROM AUTHOR]

Angular, necrotic leaf spot, longitudinal cracks along the petiole, oozing and wilting of branches were observed during summer 2008 on Actinidia chinensis (yellow kiwifruit) cultivar Hort16A, cultivated in different orchards located the province of Latina (central Italy). Symptoms closely resembled those incited by Pseudomonas syringae pv. actinidiae on kiwifruit A. deliciosa. Isolates obtained from typical lesions were assessed by means of biochemical, pathogenicity and host range tests and compared with some Pseudomonas syringae pathovars by enterobacterial repetitive intergenic consensus (ERIC-PCR) analysis. The isolates belong to Pseudomonas LOPAT group Ia, incited the death of pot-cultivated A. chinensis cv. Hort 16A and A. deliciosa cv. Hayward plants in few days, but did not cause any symptoms to the other inoculated plant species. Upon ERIC-PCR analysis, all the isolates showed similarity with P. syringae pv. actinidiae NCPPB 3739, type-strain of the pathovar. This is the first report of this pathogen on A. chinensis in Italy and, as far as we currently know, in the world. [ABSTRACT FROM AUTHOR]

Citrus blast and black pit caused by Pseudomonas syringae pv. syringae (Pss) is the only bacterial disease reported in Tunisian Citrus orchards. The phylogenetic relationship between Pss strains was studied based on multilocus sequence analysis (MLSA), using partial sequences of housekeeping genes rpoD, rpoB, gyrB, cts, and pfk for 14 representative Pss Citrus strains, including the reference strain LMG5496. The MLSA revealed that the studied Tunisian Citrus strains are closely related to LMG5496 and cluster in phylogroup 02. Based on the cts gene, the majority of Citrus strains clustered in clades "a" and "b". However, five strains were placed in a newly defined clade "g". We describe the presence of six different type III secreted effectors (T3SEs). These were found with frequencies of 100% for the effector hopAN1 and the helper hrpK1, 65% for hopT1‐2, and 14% for hopN1, hopR1, and hopQ1‐2. Investigation of copper resistance showed that 67% of our Pss Citrus strains from Tunisia are resistant to copper sulphate in vitro, and the copper resistance genes copABCDR were detected in 23% of the strains. Our results present new data concerning the genetic diversity and phylogeny, presence of T3SEs, and copper resistance within the Pss populations that affect Citrus in Tunisia. [ABSTRACT FROM AUTHOR]

SUMMARY Pseudomonas syringae pv. actinidiae is the causal agent of bacterial canker of green-fleshed kiwifruit ( Actinidia deliciosa) and yellow-fleshed kiwifruit ( A. chinensis). A recent, sudden, re-emerging wave of this disease has occurred, almost contemporaneously, in all of the main areas of kiwifruit production in the world, suggesting that it can be considered as a pandemic disease. Recent in-depth genetic studies performed on P. syringae pv. actinidiae strains have revealed that this pathovar is composed of four genetically different populations which, to different extents, can infect crops of the genus Actinidia worldwide. Genome comparisons of these strains have revealed that this pathovar can gain and lose the phaseolotoxin gene cluster, as well as mobile genetic elements, such as plasmids and putative prophages, and that it can modify the repertoire of the effector gene arrays. In addition, the strains currently causing worldwide severe economic losses display an extensive set of genes related to the ecological fitness of the bacterium in planta, such as copper and antibiotic resistance genes, multiple siderophore genes and genes involved in the degradation of lignin derivatives and other phenolics. This pathogen can therefore easily colonize hosts throughout the year. Taxonomy: Bacteria; Proteobacteria, gamma subdivision; Order Pseudomonadales; Family Pseudomonadaceae; Genus Pseudomonas; Pseudomonas syringae species complex, genomospecies 8; Pathovar actinidiae. Microbiological properties: Gram-negative, aerobic, motile, rod-shaped, polar flagella, oxidase-negative, arginine dihydrolase-negative, DNA 58.5-58.8 mol.% GC, elicits the hypersensitive response on tobacco leaves. Host range: Primarily studied as the causal agent of bacterial canker of green-fleshed kiwifruit ( Actinidia deliciosa), it has also been isolated from yellow-fleshed kiwifruit ( A. chinensis). In both species, it causes severe economic losses worldwide. It has also been isolated from wild A. arguta and A. kolomikta. Disease symptoms: In green-fleshed and yellow-fleshed kiwifruits, the symptoms include brown-black leaf spots often surrounded by a chlorotic margin, blossom necrosis, extensive twig die-back, reddening of the lenticels, extensive cankers along the main trunk and leader, and bleeding cankers on the trunk and the leader with a whitish to orange ooze. Epidemiology: Pseudomonas syringae pv. actinidiae can effectively colonize its host plants throughout the year. Bacterial exudates can disperse a large amount of inoculum within and between orchards. In the spring, temperatures ranging from 12 to 18 °C, together with humid conditions, can greatly favour the multiplication of the bacterium, allowing it to systemically move from the leaf to the young shoots. During the summer, very high temperatures can reduce the multiplication and dispersal of the bacterium. Some agronomical techniques, as well as frost, wind, rain and hail storms, can contribute to further spreading. Disease control: An integrated approach that takes into consideration precise scheduled spray treatments with effective and environmentally friendly bactericides and equilibrated plant nutrition, coupled with preventive measures aimed at drastically reducing the bacterial inoculum, currently seems to be the possible best solution for coexistence with the disease. The development of resistant cultivars and pollinators, effective biocontrol agents, including bacteriophages, and compounds that induce the systemic activation of plant defence mechanisms is in progress. Useful websites: Up-to-date information on bacterial canker research progress and on the spread of the disease in New Zealand can be found at: . Daily information on the spread of the disease and on the research being performed worldwide can be found at: . [ABSTRACT FROM AUTHOR]

Multicentre, retrospective cohort study with multivariable Cox proportional-hazards modelling and survival-time inverse-probability-weighting, evaluating the impact of different treatments on survival of proven COVID-19 patients admitted to two Hospitals in the province of Piacenza, Italy. Use of tocilizumab and of high doses of low molecular weight heparin, but not of antivirals (either alone or in combination), azithromycin, and any corticosteroid, was independently associated with lower mortality. Our results support further clinical evaluation of high doses of low molecular weight heparin and tocilizumab as COVID-19 therapeutics. [ABSTRACT FROM AUTHOR]

Since 2012, a new pathogenic syndrome has frequently been observed in many areas of kiwifruit cultivation in Italy. The main symptoms include an initial withering of the leaves followed by a total and sudden collapse of plants, mainly occurring during summer. The withered leaves fall and the main and secondary feeder roots appear rotten, sometimes showing a reddish‐brown discoloration. The disease, that affects both the green and yellow‐fleshed cultivars, has been called kiwifruit vine decline and is locally known as moria. The syndrome has been found consistently associated with soil waterlogging, which frequently occurs either after the traditional agronomical practice of irrigating orchards through surface irrigation or after very heavy rainfall. So far, the role played by bacteria in this syndrome has not been investigated. In the present study, Clostridium spp. were isolated from both rotten roots and soils obtained from Italian kiwifruit orchards affected by the syndrome, indicating for the first time that anaerobic bacteria are able to cause damage to woody crops. C. bifermentans and C. subterminale incited symptoms in kiwifruit in both in vivo and in vitro pathogenicity tests. Soil waterlogging seems to potentially favour colonization of kiwifruit roots by anaerobic bacteria, probably because saturation of the soil can facilitate proliferation and persistence of these bacteria during long periods of the vegetative growth of the crop. The occurrence of anaerobic bacteria does not exclude the possibility that other microorganisms can play additional/synergic role(s) in causing the kiwifruit vine decline. [ABSTRACT FROM AUTHOR]

The circumscription of bacterial species is a complex task. So far, DNA-DNA hybridization (DDH), 16S rRNA gene sequencing, and multiocus sequence typing analysis (MLSA) are currently the preferred techniques for their genetic determination. However, the average nucleotide identity (ANI) analysis of conserved and shared genes between two bacterial strains based on the pair-wise genome comparisons, with support of the tetranucleotide frequency correlation coefficients (TETRA) value, has recently been proposed as a reliable substitute for DDH. The species demarcation boundary has been set to a value of 95-96% of the ANI identity, with further confirmation through the assessment of the corresponding TETRA value. In this study, we performed a genome-wide MLSA of 14 phytopathogenic pseudomonads genomes, and assessed the ANI and TETRA values of 27 genomes, representing seven out of the nine genomospecies of Pseudomonas spp. sensu Gardan et alii, and their phylogenetic relationships using maximum likelihood and Bayesian approaches. The results demonstrate the existence of a well demarcated genomic cluster that includes strains classified as P. avellanae, P. syringae pv. theae, P. s. pv. actinidiae and one P. s. pv. morsprunorum strain all belonging to the single species P. avellanae. In addition, when compared with P. avellanae, five strains of P. s. pv. tomato, including the model strain DC3000, and one P. s. pv. lachrymans strain, appear as very closely related to P. avellanae, with ANI values of nearly 96% as confirmed by the TETRA analysis. Conversely, one representative strain, previously classified as P. avellanae and isolated in central Italy, is a genuine member of the P. syringae species complex and can be defined as P. s. pv. avellanae. Currently. The core and pan genomes of P. avellanae species consist of 3,995 and 5,410 putative protein-coding genes, respectively. [ABSTRACT FROM AUTHOR]