Widespread occurrence of apple proliferation disease in low-intensity orchards of Basilicata

Visual symptom assessment and PCR amplification were used to survey the occurrence of apple proliferation (AP) disease in low-intensity orchards in the Agri valley, a major cultivation area of Basilicata (southern Italy). The apple trees examined, whose cultivars were not determined as they consisted mostly of local types, were more than 20-year-old. Therefore, these plants had been exposed to insect vectors for a long time. The survey revealed that a high percentage of trees were infected reaching more than 50% in some locations. The symptoms of diseased trees were generally mild and consisted of enlarged stipules, rosettes, witches’-brooms as well as subterraneous witches’-broom-like growth arising from large roots. However, the incidence and severity of symptoms in the aerial parts of affected trees were more pronounced in trees which had been heavily pruned in the previous dormant season. Specificity of the primers used and RFLP analysis of PCR-amplified 16S rDNA sequences employing SspI and BsaAI restriction endonucleases showed that the trees testing positive by PCR were infected by the AP agent ‘Candidatus Phytoplasma mali’. The high incidence of AP infections in low-intensity orchards of the Agri valley is likely due to inappropriate vector control. The trees examined were not or rarely treated with insecticides. Although a few AP-affected apple trees grown in a low-intensity orchard in the Agri valley had previously been observed, our survey shows that the distribution of AP disease in Europe extends further south than previously thought and that the climatic conditions of southern Italy are not unsuitable for this quarantine disease

Comparison of European stone fruit yellows phytoplasma strains differing in virulence by multi-gene sequence analyses

Twenty strains of the ESFY phytoplasma, which on the basis of graft-inoculation experiments greatly differ in aggressiveness, were examined by sequence analyses of several PCR-amplified non-ribosomal genes in order to identify molecular markers linked to virulence. These strains, which were maintained in P. insititia rootstock St. Julien GF 655/2 were indistinguishable with techniques for routine phytoplasma differentiation and characterization such as sequence and RFLP analyses of PCR-amplified rDNA. Also, the virulent ESFY strains maintained in periwinkle, namely GSFY1, GSFY2 and ESFY1, as well as an avirulent strain of the same phytoplasma, maintained in apricot, which was identified in recovered apricot trees in France and used there as a cross protecting agent, were included in the work for comparison. For PCR amplification, primers were designed from a number of genes distributed over the chromosome of the closely related apple proliferation phytoplasma strain AT. Visible PCR products were only obtained with primer pairs derived from the tuf gene which encodes the elongation factor Tu (EF-Tu), rpsC (rps3) gene encoding the ribosomal protein S3, tlyC gene which encodes a hemolysin known as a membrane-damaging agent and important virulence factor of many bacteria, the imp and fol genes encoding an immunodominant membrane protein and an enzyme involved in the folate biosynthesis, respectively. Nucleotide sequence comparisons revealed that the highest genomic variability occurred within the imp gene sequence with dissimilarity values ranging from 0.2 to 4.6%. For the remaining genes, the strains examined proved to be identical or nearly identical. Within the tuf gene, an extra TaqI site known to occur in strain GSFY1 was not identified in other strains. The genetic differences observed among the strains examined are neither suitable markers for strain differentiation nor linked to pathological traits.Keywords: European stone fruit yellows, strain virulence, 16SrX group, tlyC gene, Prunus spp

History, background, concepts and current use of comedication and polypharmacy in psychiatry

Based on a careful literature search a review is presented of the history, background, concepts and current use of comedication and polypharmacy in psychiatry. The pros and cons of comedication and polypharmacy are presented, as well as their apparent increase in recent times. Possible reasons for the increase of comedication/polypharmacy are described. Both the potential advantages as well as the potential risks are discussed. The one sided view that all comedication/polypharmacy is nothing but problematic is questioned. Comedication/polypharmacy seems to be, among others, the current answer to the well-known limited efficacy and effectiveness of current monotherapy treatment strategies

Specialized 16SrX phytoplasmas induce diverse morphological and physiological changes in their respective fruit crops

The host-pathogen combinations-Malus domestica (apple)/`Candidatus Phytoplasma mali´, Prunus persica (peach)/`Ca. P. prunorum´ and Pyrus communis (pear)/`Ca. P. pyri´ show different courses of diseases although the phytoplasma strains belong to the same 16SrX group. While infected apple trees can survive for decades, peach and pear trees die within weeks to few years. To this date, neither morphological nor physiological differences caused by phytoplasmas have been studied in these host plants. In this study, phytoplasma-induced morphological changes of the vascular system as well as physiological changes of the phloem sap and leaf phytohormones were analysed and compared with non-infected plants. Unlike peach and pear, infected apple trees showed substantial reductions in leaf and vascular area, affecting phloem mass flow. In contrast, in infected pear mass flow and physicochemical characteristics of phloem sap increased. Additionally, an increased callose deposition was detected in pear and peach leaves but not in apple trees in response to phytoplasma infection. The phytohormone levels in pear were not affected by an infection, while in apple and peach trees concentrations of defence- and stress-related phytohormones were increased. Compared with peach and pear trees, data from apple suggest that the long-lasting morphological adaptations in the vascular system, which likely cause reduced sap flow, triggers the ability of apple trees to survive phytoplasma infection. Some phytohormone-mediated defences might support the tolerance

Transcriptomics assisted proteomic analysis of Nicotiana occidentalis infected by Candidatus Phytoplasma mali strain AT

Phytoplasmas are pathogenic bacteria within the class of Mollicutes, which are associated with more than 1000 plant diseases. In this study, we applied quantitative mass spectrometry to analyse affected pathways of the model plant tobacco (Nicotiana occidentalis) upon Candidatus Phytoplasma mali strain AT infection. Using tissue obtained from leaf midribs, 1466 plant-assigned proteins were identified. For 1019 of these proteins, we could reproducibly quantify the expression changes of infected versus noninfected plants, of which 157 proteins were up- and 173 proteins were downregulated. Differential expression took place in a number of pathways, among others strong downregulation of porphyrin and chlorophyll metabolism and upregulation of alpha-linolenic acid metabolism, which was consistent with observed increased levels of jasmonic acid, a key signal molecule of plant defence. Our data shed light on the molecular networks that are involved in defence of plants against phytoplasma infection and provide a resource for further studies

Old English macian, Its Origin and Dissemination

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66612/2/10.1177_007542428601900105.pd

DSM-5: a collection of psychiatrist views on the changes, controversies, and future directions

The recent release of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) by the American Psychiatric Association has led to much debate. For this forum article, we asked BMC Medicine Editorial Board members who are experts in the field of psychiatry to discuss their personal views on how the changes in DSM-5 might affect clinical practice in their specific areas of psychiatric medicine. This article discusses the influence the DSM-5 may have on the diagnosis and treatment of autism, trauma-related and stressor-related disorders, obsessive-compulsive and related disorders, mood disorders (including major depression and bipolar disorders), and schizophrenia spectrum disorders

Possible Associations of NTRK2 Polymorphisms with Antidepressant Treatment Outcome: Findings from an Extended Tag SNP Approach

Background: Data from clinical studies and results from animal models suggest an involvement of the neurotrophin system in the pathology of depression and antidepressant treatment response. Genetic variations within the genes coding for the brain-derived neurotrophic factor (BDNF) and its key receptor Trkb (NTRK2) may therefore influence the response to antidepressant treatment. Methods: We performed a single and multi-marker association study with antidepressant treatment outcome in 398 depressed Caucasian inpatients participating in the Munich Antidepressant Response Signature (MARS) project. Two Caucasian replication samples (N = 249 and N = 247) were investigated, resulting in a total number of 894 patients. 18 tagging SNPs in the BDNF gene region and 64 tagging SNPs in the NTRK2 gene region were genotyped in the discovery sample; 16 nominally associated SNPs were tested in two replication samples. Results: In the discovery analysis, 7 BDNF SNPs and 9 NTRK2 SNPs were nominally associated with treatment response. Three NTRK2 SNPs (rs10868223, rs1659412 and rs11140778) also showed associations in at least one replication sample and in the combined sample with the same direction of effects ($P_{corr}$ = .018, $P_{corr}$ = .015 and $P_{corr}$ = .004, respectively). We observed an across-gene BDNF-NTRK2 SNP interaction for rs4923468 and rs1387926. No robust interaction of associated SNPs was found in an analysis of BDNF serum protein levels as a predictor for treatment outcome in a subset of 93 patients. Conclusions/Limitations: Although not all associations in the discovery analysis could be unambiguously replicated, the findings of the present study identified single nucleotide variations in the BDNF and NTRK2 genes that might be involved in antidepressant treatment outcome and that have not been previously reported in this context. These new variants need further validation in future association studies