In vitro Analysis of Defence Mechanism in the System Solanum tuberosum-Alternaria alternata

In a preliminary study on the interaction between an Alternaria alternata pathotype and Solanum tuberosum a series of parameters, indicative of active and passive defence processes, was investigated in vitro using tolerant (Chiquita) and susceptible (Superior) cultivars. Ion leakage experiments along with growth of suspension cultures and plating efficiencies in the presence of fungal culture filtrates suggest that toxin tolerance is a valuable character in distinguishing between resistant and susceptible genotypes. As far as active defence was concerned, although TLC patterns suggested the synthesis of different fluorescent compounds, probably phenolic acid, when fungal elicitors were applied to Chiquita or susceptible tissue,cultures, no consistent pattern suggesting a relationship with defence could be observed. On the other hand, peroxidase isozyme analysis after different dual culture periods showed the activation of ionically and covalently bound peroxidases in the prese,nce of the pathogen only in cv. Chiquita.     

Unraveling the role of microRNA/isomiR network in multiple primary melanoma pathogenesis

Malignant cutaneous melanoma (CM) is a potentially lethal form of skin cancer whose worldwide incidence has been constantly increasing over the past decades. During their lifetime, about 8% of CM patients will develop multiple primary melanomas (MPMs), usually at a young age and within 3 years from the first tumor/diagnosis. With the aim of improving our knowledge on MPM biology and pathogenesis, we explored the miRNome of 24 single and multiple primary melanomas, including multiple tumors from the same patient, using a small RNA-sequencing approach. From a supervised analysis, 22 miRNAs were differentially expressed in MPM compared to single CM, including key miRNAs involved in epithelial–mesenchymal transition. The first and second melanoma from the same patient presented a different miRNA profile. Ten miRNAs, including miR-25-3p, 149-5p, 92b-3p, 211-5p, 125a-5p, 125b-5p, 205-5p, 200b-3p, 21-5p, and 146a-5p, were further validated in 47 single and multiple melanoma samples. Pathway enrichment analysis of miRNA target genes revealed a more differentiated and less invasive status of MPMs compared to CMs. Bioinformatic analyses at the miRNA isoform (isomiR) level detected a panel of highly expressed isomiRs belonging to miRNA families implicated in human tumorigenesis, including miR-200, miR-30, and miR-10 family. Moreover, we identified hsa-miR-125a-5p|0|−2 isoform as tenfold over-represented in melanoma than the canonical form and differentially expressed in MPMs arising in the same patient. Target prediction analysis revealed that the miRNA shortening could change the pattern of target gene regulation, specifically in genes implicated in cell adhesion and neuronal differentiation. Overall, we provided a putative and comprehensive characterization of the miRNA/isomiR regulatory network of MPMs, highlighting mechanisms of tumor development and molecular features differentiating this subtype from single melanomas.Subject terms: Small RNAs, Melanoma     

Anesthetics fragment hippocampal network activity,alter spine dynamics,and affect memory consolidation

General anesthesia is characterized by reversible loss of consciousness accompanied by transient amnesia. Yet, long-term memory impairment is an undesirable side effect. How different types of general anesthetics (GAs) affect the hippocampus, a brain region central to memory formation and consolidation, is poorly understood. Using extracellular recordings, chronic 2-photon imaging, and behavioral analysis, we monitor the effects of isoflurane (Iso), medetomidine/midazolam/fentanyl (MMF), and ketamine/xylazine (Keta/Xyl) on network activity and structural spine dynamics in the hippocampal CA1 area of adult mice. GAs robustly reduced spiking activity, decorrelated cellular ensembles, albeit with distinct activity signatures, and altered spine dynamics. CA1 network activity under all 3 anesthetics was different to natural sleep. Iso anesthesia most closely resembled unperturbed activity during wakefulness and sleep, and network alterations recovered more readily than with Keta/Xyl and MMF. Correspondingly, memory consolidation was impaired after exposure to Keta/Xyl and MMF, but not Iso. Thus, different anesthetics distinctly alter hippocampal network dynamics, synaptic connectivity, and memory consolidation, with implications for GA strategy appraisal in animal research and clinical settings.

Amnesia is a central part of the 200 million general anesthesia that are administered worldwide every year, but it is unclear how it affects the hippocampus. This mouse study explores how three commonly used anesthetics influence cellular network activity, spine dynamics and memory consolidation, finding that each of the three anesthetics alters the local field potential, spiking activity and cellular calcium dynamics in a unique way, and they all impact long-term spine dynamics.     

A Potential Defense Mechanism of Tomato Against the Late Blight Disease is Suppressed by Germinating Sporangia-derived Substances from Phytophthora infestans

Hypersensitive browning, host cell death and phytoalexins (rishitin) synthesis in both callus cultures and cotyledons have been observed in a susceptible tomato cultivar following treatment with high molecular weight cell wall components from Phytophthora infestans race 1B. The growth of the pathogen was restricted on both elicited differentiated and undifferentiated tomato tissues. Subtance(s) released by germinating sporangia, but not by the mycelium, suppressed the hypersensitive reaction.     

Laccase-mediated oxidation of natural glycosides

Regioselective oxidations of the primary OH's of natural glycosides (thiocolchicoside, colchicoside, amygdalin, asiaticoside, ginsenoside R_E) have been performed on a preparative scale by exploiting the laccase–2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) methodology. The influence of water-miscible organic cosolvents on the stability and activity of a laccase from Trametes pubescens has been investigated. The enzyme has been covalently linked to Eupergit C250L and its performances evaluated. The recovered immobilized enzyme catalyzed several oxidative cycles of thiocolchicoside, without showing significant loss of activity.     

OAP combination in the treatment of elderly leukaemic patients with preexisting severe internal disease

Sixteen elderly patients affected by acute non lymphoblastic leukaemia (ANLL) with a preexisting severe internal disease were treated with a low systemic toxicity drugs combination: OAP (Vincristine, Cytarabine and Prednisone). Complete remission was achieved in 5 patients (31%) after 2 OAP courses. The mean duration of remission was 18 weeks. Six patients were resistant to the therapy. Six patients died during the treatment: 5 in induction phase and 1 in consolidation phase. Even though the duration of remission was short we retain that OAP combination may be still considered a good therapeutical approach in elderly ANLL patients with associated severe internal disease.