15 research outputs found

    Evaluation of a sampling method for Xylella fastidiosa detection in olive trees

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    To assess the presence of the xylem-limited bacterium Xylella fastidiosa subsp. pauca strain CoDiRO in olive trees, a specific sampling method was evaluated. Symptomatic and symptomless plants were randomly selected in four olive orchards located in the province of Lecce (Southern Italy). The crown of each plant was subdivided into a lower and an upper portion; four samples were collected from each layer in the main four cardinal directions. A total of eight samples per plant, composed of one- or two-year-old asymptomatic twigs, were collected next to branches showing leafscorch symptoms. In this preliminary study, the null hypothesis was tested. i.e. there is no difference between the lower and the upper portions of the tree canopy and across the four cardinal directions. Samples (472), collected from 60 plants belonging to 11 different olive cultivars, were tested by qPCR. Out of 236 samples taken from the upper and lower parts of the canopy only 38.1% of lower samples, in contrast to 56.8% taken from the upper crown layer, were positive to the bacterium,. The McNemar test determined that there is a statistically significant difference in the proportion of positive samples between the upper and lower crown (p < 0.001). The Cochran’s Q test was performed to evaluate differences in the four cardinal directions. The null hypothesis suggesting there is no difference across cardinal directions was confirmed (p = 0.097). Based on these preliminary results, it appears that sampling should be directed to the upper part of the canopy. However, further studies are needed to improve the efficiency of the sampling technique

    Embryo Culture, In Vitro Propagation, and Molecular Identification for Advanced Olive Breeding Programs

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    The high biodiversity of the olive tree is an important opportunity to develop sustainable plans to control Xylella fastidiosa (Xf) through breeding programs. Olive tree breeding activities have been limited due to various features of this species including the long time required for seed germination caused by the inhibition effect of the woody endocarp, the seed integument, and the endosperm. Starting from F1 seeds by cross-breeding, the embryo culture was compared with traditional seed germination, evaluating the effectiveness of in vitro multiplication of the plantlets for large-scale production. The isolated embryos were established on a new medium based on Rugini ‘84 macroelements, Murashige & Skoog ‘62 microelements, with Nitsch J. P. & Nitsch C. ‘69 vitamine and subcultured on Leva MSM modified. The results obtained confirmed that in vitro culture of olive embryos is a valid tool for increasing the percentage and speed of germination, helping to reduce the time of the olive breeding programs, offering the possibility to effectively propagate plantlets for further experiments

    Marginal Grapevine Germplasm from Apulia (Southern Italy) Represents an Unexplored Source of Genetic Diversity

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    The investigation on the genetic diversity of grapevine germplasm is crucial for a more efficient use of grapevine genetic resources in light of changing environmental conditions. Here, we used simple sequence repeats (SSRs) coupled with single nucleotide polymorphism (SNP) markers to disclose grapevine genetic diversity of a collection of Apulian minor/neglected genotypes. Their relationships with national or international cultivars were also examined. Genetic diversity was investigated using 10 SSR markers and 1,178 SNPs generated by genotyping by sequencing (GBS). Based on the SSR data, the 128 genotypes were classified into six main genetic clusters. Twenty-four putative cases of synonymy and 2 of misnamings were detected. Ten &ldquo;unknown&rdquo; autochthonous genotypes did not show high similarity to Apulian, national, or international varieties. We took advantage of available GBS-derived SNP data points for only forty genotypes to better investigate the genetic distance among them, identify private SNP alleles, and divergent loci putatively under selection. Based on SNP alleles, two interesting gene pools of minor/neglected Apulian samples were identified. Genetic divergence was investigated by FST and allowed the detection of loci capable of differentiating the gene pools. Overall, this work emphasizes the need for recovering the untapped genetic variability that characterizes minor/neglected grapevine Apulian genotypes and the requirement to preserve and use more efficiently grapevine genetic resources in breeding programs

    Same riot/demo, different views (guest blog)

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    By Shakuntala Banaji In riposte to various UK newspapers’ and news channels’ conservative versions of reality, I would like to give an alternative account of what happened on the November 10th NUS and UCU demonstration against student fees and on the break-away part of it at 30 Millbank, the Conservative party HQ

    Erythropoietin increases GABA a currents in human cortex from TLE patients

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    Erythropoietin (EPO)is a hematopoietic growth factor that has an important role in the erythropoiesis. EPO and its receptor (EPO-R)are expressed all over in the mammalian brain. Furthermore, it has been reported that EPO may exert neuroprotective effect in animal models of brain disorders as ischemia and epilepsy. Here, we investigate whether EPO could modulate the GABA-evoked currents (I GABA )in both human epileptic and non-epileptic control brain tissues. Therefore, we transplanted in Xenopus oocytes cell membranes obtained from autoptic and surgical brain tissues (cortex)of seven temporal lope epilepsy (TLE)patients and of five control patients. Two microelectrodes voltage-clamp technique has been used to record I GABA . Moreover, qRT-PCR assay was performed in the same human tissues to quantify the relative gene expression levels of EPO/EPO-R. To further confirm experiments in oocytes, we performed additional experiments using patch-clamp recording in slices obtained from rat cerebellum. We show that exposure to EPO significantly increased the amplitude of the I GABA in all the patients analyzed. No differences in the expression of EPO and EPO-R in both TLE and control patients have been found. Notably, the increase of I GABA has been recorded also in rat cerebellar slices. Our findings show a new modulatory action of EPO on GABA A receptors (GABA A -Rs). This effect could be relevant to balance the GABAergic dysfunction in human TLE

    Presentation_1_Breeding new seedless table grapevines for a more sustainable viticulture in Mediterranean climate.pptx

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    The growing demand for sustainable and environmentally friendly viticulture is leading to a multiplication of breeding programs aimed at obtaining vines that are resistant to powdery mildew (PM) and downy mildew (DM), the two most damaging vine diseases. In Puglia, the most important Italian region for the production of table grapes, an extensive crossing program was launched in 2015 with 113 crosses, including elite table varieties, seedless varieties, and resistant varieties. The main seedling production parameters were measured for each cross. In particular, berries harvested as well as the number of seeds and seedlings obtained were considered. Approximately 103,119 seedlings were obtained and subjected to marker-assisted selection for seedlessness using the marker VvAGL11 and for resistance to PM and DM with appropriate markers. Approximately one third (32,638) of the progenies were selected as putative seedless and seventeen thousand five hundred-nine (17,509) were transferred to the field for phenotypic evaluation, including 527 seedless individuals putatively resistant, of which 208 confirmed to be resistant to DM, 22 resistant to PM, and 20 individuals that combined resistance and seedlessness traits. The work discusses the effects of parental combinations and other variables in obtaining surviving progeny and pyramiding genes in table grapes and provides useful information for selecting genotypes and increasing the efficiency of breeding programs for seedless disease-resistant grapes.</p

    GABAA-current rundown of temporal lobe epilepsy is associated with repetitive activation of GABAA “phasic” receptors

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    A study was made of the “rundown” of GABAA receptors, microtransplanted to Xenopus oocytes from surgically resected brain tissues of patients afflicted with drug-resistant human mesial temporal lobe epilepsy (mTLE). Cell membranes, isolated from mTLE neocortex specimens, were injected into frog oocytes that rapidly incorporated functional GABAA receptors. Upon repetitive activation with GABA (1 mM), “epileptic” GABAA receptors exhibited a GABAA-current (IGABA) rundown that was significantly enhanced by Zn2+ (≀250 ÎŒM), and practically abolished by the high-affinity GABAA receptor inverse agonist SR95531 (gabazine; 2.5–25 ÎŒM). Conversely, IGABA generated by “control” GABAA receptors microtransplanted from nonepileptic temporal lobe, lesional TLE, or authoptic disease-free tissues remained stable during repetitive stimulation, even in oocytes treated with Zn2+. We conclude that rundown of mTLE epileptic receptors depends on the presence of “phasic GABAA receptors” that have low sensitivity to antagonism by Zn2+. Additionally, we found that GABAA receptors, microtransplanted from the cerebral cortex of adult rats exhibiting recurrent seizures, caused by pilocarpine-induced status epilepticus, showed greater rundown than control tissue, an event also occurring in patch-clamped rat pyramidal neurons. Rundown of epileptic rat receptors resembled that of human mTLE receptors, being enhanced by Zn2+ (40 ÎŒM) and sensitive to the antiepileptic agent levetiracetam, the neurotrophin brain-derived neurotrophic factor, and the phosphatase blocker okadaic acid. Our findings point to the rundown of GABAA receptors as a hallmark of TLE and suggest that modulating tonic and phasic mTLE GABAA receptor activity may represent a useful therapeutic approach to the disease

    GABA(A)-current rundown of temporal lobe epilepsy is associated with repetitive activation of GABA(A) "phasic" receptors

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    A study was made of the "rundown" of GABA(A) receptors, microtransplanted to Xenopus oocytes from surgically resected brain tissues of patients afflicted with drug-resistant human mesial temporal lobe epilepsy (mTLE). Cell membranes, isolated from mTLE neocortex specimens, were injected into frog oocytes that rapidly incorporated functional GABA(A) receptors. Upon repetitive activation with GABA (1 mM), "epileptic" GABA(A) receptors exhibited a GABA(A)-current (I(GABA)) rundown that was significantly enhanced by Zn(2+) (</=250 microM), and practically abolished by the high-affinity GABA(A) receptor inverse agonist SR95531 (gabazine; 2.5-25 microM). Conversely, I(GABA) generated by "control" GABA(A) receptors microtransplanted from nonepileptic temporal lobe, lesional TLE, or authoptic disease-free tissues remained stable during repetitive stimulation, even in oocytes treated with Zn(2+). We conclude that rundown of mTLE epileptic receptors depends on the presence of "phasic GABA(A) receptors" that have low sensitivity to antagonism by Zn(2+). Additionally, we found that GABA(A) receptors, microtransplanted from the cerebral cortex of adult rats exhibiting recurrent seizures, caused by pilocarpine-induced status epilepticus, showed greater rundown than control tissue, an event also occurring in patch-clamped rat pyramidal neurons. Rundown of epileptic rat receptors resembled that of human mTLE receptors, being enhanced by Zn(2+) (40 microM) and sensitive to the antiepileptic agent levetiracetam, the neurotrophin brain-derived neurotrophic factor, and the phosphatase blocker okadaic acid. Our findings point to the rundown of GABA(A) receptors as a hallmark of TLE and suggest that modulating tonic and phasic mTLE GABA(A) receptor activity may represent a useful therapeutic approach to the disease

    Table_1_Breeding new seedless table grapevines for a more sustainable viticulture in Mediterranean climate.xlsx

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    The growing demand for sustainable and environmentally friendly viticulture is leading to a multiplication of breeding programs aimed at obtaining vines that are resistant to powdery mildew (PM) and downy mildew (DM), the two most damaging vine diseases. In Puglia, the most important Italian region for the production of table grapes, an extensive crossing program was launched in 2015 with 113 crosses, including elite table varieties, seedless varieties, and resistant varieties. The main seedling production parameters were measured for each cross. In particular, berries harvested as well as the number of seeds and seedlings obtained were considered. Approximately 103,119 seedlings were obtained and subjected to marker-assisted selection for seedlessness using the marker VvAGL11 and for resistance to PM and DM with appropriate markers. Approximately one third (32,638) of the progenies were selected as putative seedless and seventeen thousand five hundred-nine (17,509) were transferred to the field for phenotypic evaluation, including 527 seedless individuals putatively resistant, of which 208 confirmed to be resistant to DM, 22 resistant to PM, and 20 individuals that combined resistance and seedlessness traits. The work discusses the effects of parental combinations and other variables in obtaining surviving progeny and pyramiding genes in table grapes and provides useful information for selecting genotypes and increasing the efficiency of breeding programs for seedless disease-resistant grapes.</p

    Blockage of A(2A) and A(3) adenosine receptors decreases the desensitization of human GABA(A) receptors microtransplanted to Xenopus oocytes

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    We previously found that the endogenous anticonvulsant adenosine, acting through A(2A) and A(3) adenosine receptors (ARs), alters the stability of currents (IGABA) generated by GABA(A) receptors expressed in the epileptic human mesial temporal lobe (MTLE). Here we examined whether ARs alter the stability (desensitization) of IGABA expressed in focal cortical dysplasia (FCD) and in periglioma epileptic tissues. The experiments were performed with tissues from 23 patients, using voltage-clamp recordings in Xenopus oocytes microinjected with membranes isolated from human MTLE and FCD tissues or using patch-clamp recordings of pyramidal neurons in epileptic tissue slices. On repetitive activation, the epileptic GABA(A) receptors revealed instability, manifested by a large I-GABA rundown, which in most of the oocytes (approximate to 70%) was obviously impaired by the new A(2A) antagonists ANR82, ANR94, and ANR152. In most MTLE tissue-microtransplanted oocytes, a new A(3) receptor antagonist (ANR235) significantly improved I-GABA stability. Moreover, patch-clamped pyramidal neurons from human neocortical slices of periglioma epileptic tissues exhibited altered I-GABA rundown on ANR94 treatment. Our findings indicate that antagonizing A(2A) and A(3) receptors increases the I-GABA stability in different epileptic tissues and suggest that adenosine derivatives may offer therapeutic opportunities in various forms of human epilepsy
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