230 research outputs found

    Microalgae cultivation for lipids and carbohydrates production

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    Microalgae are photoautotrophic microorganisms that can produce energy both by using sunlight, water and CO2 (phototrophic metabolism) and by using organic sources such as glucose (heterotrophic metabolism). Heterotrophic growth is a key factor in microalgae research, due to its increased productivity and the lower capital and operative costs compared to photoautotrophic growth in photobioreactors. Carbohydrate production from microalgae is usually investigated for the production of biofuels (e.g. bioethanol) by successive fermentation, but also other applications can be envisaged in biopolymers. In this work an increment in carbohydrate purity after lipid extraction was found. Protein hydrolysis for different microalgae strains (Scenedesmus sp. and Chlorella sp.) was investigated. Microalgae were cultivated under photoautotrophic or heterotrophic conditions, collecting biomass at the end of the growth. Biomass samples were dried or freeze dried and used for carbohydrate and lipid extraction tests. Lipid extraction was achieved using different organic solvents (methanol-chloroform and hexane-2propanol). Basic protein hydrolysis has been carried out testing different temperatures and NaOH concentrations values. Lipids were spectrophotometrically quantified, while residual biomass was saccharificated and the total amount of sugars was measured. Significant differences about the purity of extracted carbohydrates were found comparing dried with freeze dried biomass. However, not a very promising purification of carbohydrates was achieved after protein hydrolysis, asking for further analysis. © Copyright 2017, AIDIC Servizi S.r.l

    A new species of <i>Dasyhelea</i> from Brazilian Amazonas and the description of the male of <i>D. paulistana</i> (Diptera: Ceratopogonidae)

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    A new species, Dasyhelea pseudopollinosa Díaz & Ronderos sp. nov., is described from Brazil, illustrated and photographed as pupae and male and female adults. The male of D. paulistana Forattini & Rabello, 1957 is described for the first time, and the pupa and female adult are redescribed. Pupae of both species were collected from mats of floating fern leaves (Salviniaceae and Azollaceae) in Brazil and Argentina, and exhibit a respiratory organ which is thick at the base and tapering to a sharp apex, and segment 9 with elongate, slender apicolateral process. Diffe rences between the two species are established, and they are also compared with Nearctic congeners that have the same kind of pupa: D. pollinosa Wirth, 1952, D. traverae Thomsen, 1935, and D. chani Wirth & Linley, 1990.Facultad de Ciencias Naturales y Museo (FCNM

    A new species of <i>Dasyhelea</i> from Brazilian Amazonas and the description of the male of <i>D. paulistana</i> (Diptera: Ceratopogonidae)

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    A new species, Dasyhelea pseudopollinosa Díaz & Ronderos sp. nov., is described from Brazil, illustrated and photographed as pupae and male and female adults. The male of D. paulistana Forattini & Rabello, 1957 is described for the first time, and the pupa and female adult are redescribed. Pupae of both species were collected from mats of floating fern leaves (Salviniaceae and Azollaceae) in Brazil and Argentina, and exhibit a respiratory organ which is thick at the base and tapering to a sharp apex, and segment 9 with elongate, slender apicolateral process. Diffe rences between the two species are established, and they are also compared with Nearctic congeners that have the same kind of pupa: D. pollinosa Wirth, 1952, D. traverae Thomsen, 1935, and D. chani Wirth & Linley, 1990.Facultad de Ciencias Naturales y Museo (FCNM

    Modulation of Antioxidant Compounds in Fruits of Citrus reticulata Blanco Using Postharvest LED Irradiation

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    Phlegrean mandarin fruits are already known for health-promoting properties due to the high concentration of phytochemicals in peel, pulp, and seed. Biotic and abiotic factors, including light, may modulate their biosynthesis, metabolism, and accumulation. In this context, light-emitting diodes (LED) have recently been applied to control nutritional traits, ripening process, senescence, fruit shelf-life, and pathogenic microbial spoilage of fruits. This study investigated the effect of the seven-day exposure of Phlegrean mandarin fruits to two LED regimes, white (W) and red–blue (RB), to test the possibility that the storage under specific light wavelengths may be used as green preservation technology that enhances fruit phytochemical properties. To pursue this aim, the antioxidant activity and polyphenolic profile of the pulp and peel of mandarins under W and RB light regimes were evaluated and compared with Control fruits not exposed to LED treatment. Our results indicated that storage under W and RB treatments modulates the antioxidant content in pulp and peel differently. Compared to W, the RB regime increases the ascorbic acid, flavonoid, anthocyanin, and carotenoid concentrations, while the polyphenol profile analysis reveals that the number of important phytochemicals, i.e., quercetin rutinoside, chlorogenic acid, sinensetin, and rutin, are higher under W. The overall data demonstrated that postharvest LED irradiation is a valid tool for modifying fruit phytochemical properties, which also boosts specific bioactive compounds

    A new species of <i>Stilobezzia</i> Kieffer from the Neotropical Region (Diptera, Ceratopogonidae)

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    A new species from the Neotropical Region, Stilobezzia (Stilobezzia) pseudopunctulata Cazorla & Ronderos, is described and illustrated based on male and female adults and pupal exuviae. Adults were collected in the Argentinian provinces of Chaco, Formosa, Corrientes and Buenos Aires, and in Santa Cruz, Bolivia. The pupa was collected from mats of floating aquatic macrophytes in a lagoon in Ilha da Marchantería, in the vicinities of Manaus, Brazil. This new species is compared with its similar congener Stilobezzia punctulata Lane, from which it can be mainly distinguished by the wing with only two dark spots, the parameres longer and hook-shaped, the pupal respiratory organ with 11-12 pores and the very short apicolateral processes of the anal segment.Facultad de Ciencias Naturales y Museo (FCNM

    Prevalence, sensitivity and specificity of antibodies against carbamylated proteins in a monocentric cohort of patients with rheumatoid arthritis and other autoimmune rheumatic diseases

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    Antibodies against carbamylated proteins (anti-CarP) have been recently identified in the sera of patients with rheumatoid arthritis (RA). The objective of the study was to evaluate the prevalence, sensitivity and specificity of anti-CarP compared to anti-citrullinated peptide antibodies (ACPA) and rheumatoid factor (RF), replicating the existing data in a large cohort of Italian patients with RA and extending the evaluation to other autoimmune rheumatic diseases (AIRDs)

    Purification and characterization of a Cys-Gly hydrolase from the gastropod mollusk, Patella caerulea

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    A magnesium-dependent cysteinyl-glycine hydrolyzing enzyme from the gastropod mollusk Patella caerulea was purified to electrophoretic homogeneity through a simple and rapid purification protocol. The molecular masses of the native protein and the subunit suggest that the enzyme has a homohexameric structure. Structural data in combination with kinetic parameters determined with Cys-Gly and compared with Leu-Gly as a substrate, indicate that the purified enzyme is a member of the peptidase family M17. The finding that an enzyme of the peptidase family M17 is responsible also in mollusks for the breakdown of Cys-Gly confirms the important role of this peptidase family in the glutathione metabolism

    Hypoxia inducible factor-1β regulates a pro-invasive phenotype in acute monocytic leukemia

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    Hypoxia inducible transcription factors (HIFs) are the main regulators of adaptive responses to hypoxia and are often activated in solid tumors, but their role in leukemia is less clear. In acute myeloid leukemia (AML), in particular, controversial new findings indicate that HIF-1β can act either as an oncogene or a tumor suppressor gene, and this may depend on the stage of leukemia development and/or the AML sub-type. In this study, we find that HIF-1β promotes leukemia progression in the acute monocytic leukemia sub-type of AML through activation of an invasive phenotype. By applying a list of validated HIF-1β-target genes to different AML sub-types, we identified a HIF-1β signature that typifies acute monocytic leukemia when compared with all other AML sub-types. We validated expression of this signature in cell lines and primary cells from AML patients. Interestingly, this signature is enriched for genes that control cell motility at different levels. As a consequence, inhibiting HIF- 1β impaired leukemia cell migration, chemotaxis, invasion and transendothelial migration in vitro, and this resulted in impaired bone marrow homing and leukemia progression in vivo. Our data suggest that in acute monocytic leukemia an active HIF-1β-dependent pro-invasive pathway mediates the ability of leukemic cells to migrate and invade extramedullary sites and may be targeted to reduce leukemia dissemination

    A computational procedure to identify significant overlap of differentially expressed and genomic imbalanced regions in cancer datasets†

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    The integration of high-throughput genomic data represents an opportunity for deciphering the interplay between structural and functional organization of genomes and for discovering novel biomarkers. However, the development of integrative approaches to complement gene expression (GE) data with other types of gene information, such as copy number (CN) and chromosomal localization, still represents a computational challenge in the genomic arena. This work presents a computational procedure that directly integrates CN and GE profiles at genome-wide level. When applied to DNA/RNA paired data, this approach leads to the identification of Significant Overlaps of Differentially Expressed and Genomic Imbalanced Regions (SODEGIR). This goal is accomplished in three steps. The first step extends to CN a method for detecting regional imbalances in GE. The second part provides the integration of CN and GE data and identifies chromosomal regions with concordantly altered genomic and transcriptional status in a tumor sample. The last step elevates the single-sample analysis to an entire dataset of tumor specimens. When applied to study chromosomal aberrations in a collection of astrocytoma and renal carcinoma samples, the procedure proved to be effective in identifying discrete chromosomal regions of coordinated CN alterations and changes in transcriptional levels

    321. Sea Urchin sns Chromatin Insulator Prevents Silencing and Positional Effect Variegation of Oncoretroviral Vectors Transgene Expression in Murine Erythroid Cell Line

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    Silencing and position effect are considered significant obstacles to obtain a consistent level of transgene expression in viral gene therapy. Furthermore recent studies had shown that retroviruses tend to land on active genes with the potential consequence of insertional mutagenesis. The inclusion of elements, such as chromatin insulators, capable to insulate a gene from the surrounding chromatin effects at the integration site should improve both efficacy and safety of gene therapy vectors. We have previously characterized a 265 bp insulator element, termed sns, localized at the 3' end of the early histone H2A gene of the sea urchin Paracentrotus lividus. This sequence contains three cis-acting elements (Box A, Box B, and Box C+T) all needed for the enhancer blocking activity in both sea urchin and human cells. By colony assays, in human (K562) and mouse (Mel) erythroid cell lines, we have recently demonstrated that the sns insulator displays directional enhancer-blocking activity in that it interferes with the communication between the human beta-globin enhancer (LCR) and the gamma-globin promoter. By electrophoretic mobility shift assays (EMSA) we found bindings of sns insulator with the erythroid specific GATA1 and the ubiquitous Oct1, and Sp1 transcription factors
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