146 research outputs found

    Agronomic-productive Characteristics of Two Genotype of Stevia Rebaudiana in Central Italy

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    Stevia rebaudiana Bertoni produces a variety of high-potency low calorie sweeteners in its' leaf tissue. The aim of this work was to evaluate the productive potential of two different Stevia rebaudiana genotypes and the characteristics of the production of the plant obtained through different cultivation methods, in central Italy. For several years (1992-2000) agronomic trials on Stevia rebaudiana cultivated in the littoral area near Pisa (Italy) carried out. In 1992 two different genotypes of Stevia (B1 and B2) transplanted in silt-loam soil; in 1996 other plants from B2 genotype, produced by vegetative process (micropropagation), were transplanted in the same field. In the period from 1992-1999 the production of leaves from both genotypes increase as of the third year and the ratio leaf-aerial plant, after the peak in the third year, tends to diminish. Except the first year (1997) there were not recorded statistically significant differences between the two propagation methods employed in relation to leaf production. The quantity of leaves produced from a single harvest was less than resulting from two cuttings and the micropropagation plants produced a larger amount of leaves than those from cutting. The leaf-stem ratio was to become an interesting morphological and production characteristic parameter of the plant. Stevia rebaudiana appears particularly suited for the cultivation environment of central Italy. A particular positive aspect that must be considered in these regions is that Stevia can be grown successfully as poliannual species because crop survival over the winter is high. The results obtained show that this species is economically profitable until the 5th or 6th year of cultivation. At our latitudes is also necessary to establish a program of genetic improvement in order to develop earlier varieties that can guaranty an optimum qualitative and quantitative seed production

    Effects of Temperature, Light and Pre-Chilling on Seed Germination of Stevia rebaudiana (Bertoni) Bertoni Accessions

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    Stevia rebaudiana (Bertoni) Bertoni is a perennial shrub of the Asteraceae family native to Paraguay and Brazil where it has been used for several years as a sweetener. It is a short-day species, with a critical light requirement for flowering of roughly 13 hours. In plants whose biological cycle is strongly photoperiod-dependent, latitude is one of the major factors influencing reproduction. Late flowering may adversely affect seed production if this occurs during a season that is unfavorable to pollination. At Italian latitudes, this species often gives scanty seed production, with low germination rate and poor germination energy of seeds produced. In 2001 four accessions have been grown for seed production in a field plot experiment in Central Italy. The various accessions were found to exhibit noticeably different photoperiod requirements, which affected flowering time (from late August to the end of September) and consequently also the conditions of achene filling and ripening. Late flowering and seed ripening occurred during autumn season, unfavourable to complete seed formation, leading to an increase in the empty seed percentage recorded for each accession. Detailed germination trials were therefore undertaken using seeds collected from plants of the different accessions in order to assess the quality of the seeds produced. Various germination methods have been tested in a controlled environment adopting four different temperatures (20° C, 25° C constant temperature and 15/25° C, 20/30° C (16/8h) alternating temperature) in light or darkness with or without pre-chilling. Germination rates varied over an extensive range (germination percentage from 9 to 83%), mainly due to the divergent specific characteristics of the material examined and the different treatments studied. At all temperatures tested, the most earlier accession, showed the higher germination percentages (54-83%) while the latest accession was among those with the lowest germination values (9-44%). Overall, at the constant temperatures assayed, pre-chilling gave a higher germination percentage as compared to no pre-chilling, while at alternating temperatures higher germination rates were obtained in the absence of pre-chilling. The great variability observed between accessions for photoperiodic requirement as well as in seed germinative characteristics was probably due to the fact that this species was not subjected to any genetic improvement program

    Surface Plasmon Resonance Assay for Label-Free and Selective Detection of Xylella Fastidiosa

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    Xylella fastidiosa is among the most dangerous plant bacteria worldwide causing a variety of diseases, with huge economic impact on agriculture and environment. A surveillance tool, ensuring the highest possible sensitivity enabling the early detection of X. fastidiosa outbreaks, would be of paramount importance. So far, a variety of plant pathogen biomarkers are studied by means of surface plasmon resonance (SPR). Herein, multiparameter SPR (MP-SPR) is used for the first time to develop a reliable and label-free detection method for X. fastidiosa. The real-time monitoring of the bioaffinity reactions is provided as well. Selectivity is guaranteed by biofunctionalizing the gold transducing interface with polyclonal antibodies for X. fastidiosa and it is assessed by means of a negative control experiment involving the nonbinding Paraburkholderia phytofirmans bacterium strain PsJN. Limit of detection of 105 CFU mL 1 is achieved by transducing the direct interaction between the bacterium and its affinity antibody. Moreover, the binding affinity between polyclonal antibodies and X. fastidiosa bacteria is also evaluated, returning an affinity constant of 3.5   107m 1, comparable with those given in the literature for bacteria detection against affinity antibodies

    Orphan drugs in Italy: availability and time-to-access at regional level

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    Introduction: There are an estimated 26 million rare disease patients in Europe, about 2 million in Italy. Access to orphan drugs has been evaluated nationally and internationally, and delays have been observed due to evaluation of price and therapeutic value. The objectives of this study are: to assess the availability of EMA-authorized orphan drugs at national and regional level; to study time trends and regional variability in consumption and spending, and to estimate the time to access in Italian regions. Methods: We evaluate the availability of EMA authorized orphan drugs in Italy. Based on data from the Traceability of medicines dataflow for period 2016-2021 we evaluate the expenditure, consumption and availability of orphan drugs in each region. To estimate the time to access we consider the days between the end of negotiation procedure and the first purchase by regions. Results: In 2021 in Italy are available 94% of EMA authorized orphan drugs. The expenditure and consumption have grown during the last decade. The availability is higher in bigger regions, that also take care of patients from smaller regions. The pro capite expenditure and consumption in DDD/1,000 ab die is similar in all the geographic area. Time to regional access is on average 123 days, that grows to 224 excluding the orphan drugs dispensed before the end of reimbursement procedure

    Identification and Functional Characterization of a Novel Mutation in theNKX2-1Gene: Comparison with the Data in the Literature

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    Background: NKX2-1 mutations have been described in several patients with primary congenital hypothyroidism, respiratory distress, and benign hereditary chorea, which are classical manifestations of the brain-thyroid-lung syndrome (BTLS). Methods: The NKX2-1 gene was sequenced in the members of a Brazilian family with clinical features of BTLS, and a novel monoallelic mutation was identified in the affected patients. We introduced the mutation in an expression vector for the functional characterization by transfection experiments using both thyroidal and lung-specific promoters. Results: The mutation is a deletion of a cytosine at position 834 (ref. sequence NM-003317) (c.493delC) that causes a frameshift with formation of an abnormal protein from amino acid 165 and a premature stop at position 196. The last amino acid of the nuclear localization signal, the whole homeodomain, and the carboxy-terminus of NKX2-1 are all missing in the mutant protein, which has a premature stop codon at position 196 (p.Arg165Glyfs*32). The p.Arg165Glyfs*32 mutant does not bind DNA, and it is unable to transactivate the thyroglobulin (Tg) and the surfactant protein-C (SP-C) promoters. Interestingly, a dose-dependent dominant negative effect of the p.Arg165Glyfs*32 was demonstrated only on the Tg promoter, but not on the SP-C promoter. This effect was also noticed when the mutation was tested in presence of PAX8 or cofactors that synergize with NKX2-1 (P300 and TAZ). The functional effect was also compared with the data present in the literature and demonstrated that, so far, it is very difficult to establish a specific correlation among NKX2-1 mutations, their functional consequence, and the clinical phenotype of affected patients, thus suggesting that the detailed mechanisms of transcriptional regulation still remain unclear. Conclusions: We describe a novel NKX2-1 mutation and demonstrate that haploinsufficiency may not be the only explanation for BTLS. Our results indicate that NKX2-1 activity is also finely regulated in a tissue-specific manner, and additional studies are required to better understand the complexities of genotype-phenotype correlations in the NKX2-1 deficiency syndrome

    A Single-Molecule Bioelectronic Portable Array for Early Diagnosis of Pancreatic Cancer Precursors

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    A cohort of 47 patients is screened for pancreatic cancer precursors with a portable 96-well bioelectronic sensing-array for single-molecule assay in cysts fluid and blood plasma, deployable at point-of-care (POC). Pancreatic cancer precursors are mucinous cysts diagnosed with a sensitivity of at most 80% by state-of-the-art cytopathological molecular analyses (e.g., KRASmut DNA). Adding the simultaneous assay of proteins related to malignant transformation (e.g., MUC1 and CD55) is deemed essential to enhance diagnostic accuracy. The bioelectronic array proposed here, based on single-molecule-with-a-large-transistor (SiMoT) technology, can assay both nucleic acids and proteins at the single-molecule limit-of-identification (LOI) (1% of false-positives and false-negatives). It comprises an enzyme-linked immunosorbent assay (ELISA)-like 8 Ă— 12-array organic-electronics disposable cartridge with an electrolyte-gated organic transistor sensor array, and a reusable reader, integrating a custom Si-IC chip, operating via software installed on a USB-connected smart device. The cartridge is complemented by a 3D-printed sensing gate cover plate. KRASmut, MUC1, and CD55 biomarkers either in plasma or cysts-fluid from 5 to 6 patients at a time, are multiplexed at single-molecule LOI in 1.5 h. The pancreatic cancer precursors are classified via a machine-learning analysis resulting in at least 96% diagnostic-sensitivity and 100% diagnostic-specificity. This preliminary study opens the way to POC liquid-biopsy-based early diagnosis of pancreatic-cancer precursors in plasma.</p

    The MONARCH high-resolution reanalysis of desert dust aerosol over Northern Africa, the Middle East and Europe (2007-2016)

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    One of the challenges in studying desert dust aerosol along with its numerous interactions and impacts is the paucity of direct in-situ measurements, particularly in the areas most affected by dust storms. Satellites typically provide columnintegrated aerosol measurements, but observationally-constrained continuous 3D dust fields are needed to assess dust variability, climate effects and impacts upon a variety of socio-economic sectors. Here, we present a high resolution regional reanalysis data set of desert dust aerosols that covers Northern Africa, the Middle East and Europe along with the Mediterranean sea and parts of Central Asia, and the Atlantic and Indian Oceans between 2007 and 2016. The horizontal resolution is 0.1° latitude × 0.1° longitude, and the temporal resolution is 3 hours. The reanalysis was produced using Local Ensemble Transform Kalman Filter (LETKF) data assimilation in the Multiscale Online Non-hydrostatic AtmospheRe CHemistry model (MONARCH) developed at the Barcelona Supercomputing Center (BSC). The assimilated data are coarse-mode dust optical depth retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS) Deep Blue Level 2 products. The reanalysis data set consists of upper air (dust mass concentrations and extinction coefficient), surface (dust deposition and solar irradiance fields, among them) and total column (e.g., dust optical depth and load) variables. Some dust variables, such as concentrations and wet and dry deposition, are expressed for a binned size distribution that ranges from 0.2 to 20 μm in particle diameter. Both analysis and first-guess (analysis-initialized simulation) fields are available for the variables that are diagnosed from the state vector.We acknowledge the DustClim project which is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union’s Horizon 2020 research and innovation programme (Grant n. 690462)
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