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41.
42.
Maria del Rosario Martínez-Macias Rocio Janeth Aguilar-Ruiz Omar Nateras-Ramírez Dalia Isabel Sánchez-Machado Jaime López-Cervantes Germán Eduardo Dévora-Isiordia Jesús Álvarez-Sánchez Nidia Josefina Ríos-Vázquez 《Journal of the American Oil Chemists' Society》2021,98(10):993-1000
Greenhouse gases emitted into the atmosphere by burning of fossil fuels cause global warming. One option is obtaining biodiesel. Nannochloropsis oculata was cultured under different light intensities and reactors at 25°C for 21 days with f/2 medium to assess their effects on cell density, lipid, and fatty acids (FAs). N. oculata improved cell density on fed-batch glass tubular reactor (7 L) at 200 μmol E m−2 s−1, yielding 3.5 × 108 cells ml−1, followed by fed-batch Erlenmeyer flask (1 L) at 650 μmol E m−2 s−1 with 1.7 × 108 cells ml−1. The highest total lipid contents (% g lipid × g dry biomass−1) were 44.4 ± 0.8% for the reactor (1 L) at 650 μmol E m−2 s−1 and 35.2 ± 0.2% for the tubular reactor (7 L) at 200 μmol E m−2 s−1, until twice as high compared with the control culture (Erlenmeyer flask 1 L, 80 μmol E m−2 s−1) with 21.2 ± 1%. Comparing the total lipid content at 200 μmol E m−2 s−1, tubular reactor (7 L) and reactor 1 L achieved 35.2 ± 0.2% and 28.3 ± 1%, respectively, indicating the effect of shape reactor. The FAs were affected by high light intensity, decreasing SFAs to 2.5%, and increased monounsaturated fatty acids + polyunsaturated fatty acids to 2.5%. PUFAs (20:5n-3) and (20:4n-3) were affected by reactor shape, decreasing by half in the tubular reactor. In the best culture, fed-batch tubular reactor (7 L) at 200 μmol E m−2 s−1 contains major FAs (16:0; 38.06 ± 0.16%), (16:1n-7; 30.74 ± 0.58%), and (18:1n-9; 17.15 ± 0.91%). 相似文献
43.
Guadalupe Rosario Fajardo-Ordua Edgar Ledesma-Martínez Itzen Aguiiga-Snchez María de Lourdes Mora-García Benny Weiss-Steider Edelmiro Santiago-Osorio 《International journal of molecular sciences》2021,22(9)
Acute myeloid leukemia (AML), the most common type of leukemia in older adults, is a heterogeneous disease that originates from the clonal expansion of undifferentiated hematopoietic progenitor cells. These cells present a remarkable variety of genes and proteins with altered expression and function. Despite significant advances in understanding the molecular panorama of AML and the development of therapies that target mutations, survival has not improved significantly, and the therapy standard is still based on highly toxic chemotherapy, which includes cytarabine (Ara-C) and allogeneic hematopoietic cell transplantation. Approximately 60% of AML patients respond favorably to these treatments and go into complete remission; however, most eventually relapse, develop refractory disease or chemoresistance, and do not survive for more than five years. Therefore, drug resistance that initially occurs in leukemic cells (primary resistance) or that develops during or after treatment (acquired resistance) has become the main obstacle to AML treatment. In this work, the main molecules responsible for generating chemoresistance to Ara-C in AML are discussed, as well as some of the newer strategies to overcome it, such as the inclusion of molecules that can induce synergistic cytotoxicity with Ara-C (MNKI-8e, emodin, metformin and niclosamide), subtoxic concentrations of chemotherapy (PD0332991), and potently antineoplastic treatments that do not damage nonmalignant cells (heteronemin or hydroxyurea + azidothymidine). 相似文献
44.
Rodrı X Guez MA Garcı X A T González I Asensio L Mayoral B López-Calleja I Hernández PE Martı X N R 《Meat science》2003,65(4):1257-1263
Polymerase chain reaction amplification of a conserved region of the -actin gene has been used for the specific identification of goose (Anser anser) and mule duck (Anas platyrhynchos×Cairina moschata) foie gras. Universal primers were used for the amplification of a DNA fragment containing three introns and four exons of the -actin gene in goose and mule duck. Sequence analysis of the amplified fragments was necessary for the design of forward species-specific primers in the goose and mule duck -actin genes. The use of species-specific forward primers, together with a reverse universal primer, produced amplicons of different length, allowing clear identification of goose and mule duck foie gras samples. Analysis of experimental mixtures demonstrated that 1% of duck can be easily detected in goose foie gras using the PCR method developed here. This genetic marker can be very useful for the accurate identification of these two species in foie gras products. 相似文献
45.
Alessandro Lapadula Rosario Pugliese Francesco Tiezzi 《Electronic Notes in Theoretical Computer Science》2008,200(3):133
To provide formal foundations to current (web) services technologies, we put forward using COWS, a process calculus for specifying, combining and analysing services, as a uniform formalism for modelling all the relevant phases of the life cycle of service-oriented applications, such as publication, discovery, negotiation, deployment and execution. In this paper, we show that constraints and operations on them can be smoothly incorporated in COWS, and propose a disciplined way to model multisets of constraints and to manipulate them through appropriate interaction protocols. Therefore, we demonstrate that also QoS requirement specifications and SLA achievements, and the phases of dynamic service discovery and negotiation can be comfortably modelled in COWS. We illustrate our approach through a scenario for a service-based web hosting provider. 相似文献
46.
Reduced protein quality is one of the concerns currently confronting the supply and utilization of wheat distillers dried grain with solubles (DDGS) as an animal feed ingredient. This study assessed the protein quality of wheat DDGS, expressed as acid detergent insoluble crude protein (ADICP) and lysine content, by blending wet distillers grain (WDG) with varying condensed distillers solubles (CDS) levels and drying using forced air convection, microwave, and microwave–convection methods. As the CDS level was increased, the protein content of wheat DDGS generated from the three drying methods increased. Interactions of CDS level with drying air temperature, microwave power, and microwave–convection settings had a significant effect (p < 0.05) on average ADICP and lysine contents. Higher ADICP and lower lysine contents were observed in samples dried at higher temperature, microwave power, and microwave convection settings. Further, the CDS level significantly affected the color parameters of microwave- and microwave–convection-dried samples and the drying air temperature–CDS level interaction significantly affected the color of forced air convection–dried samples. Significant lysine content–redness, ADICP–lightness color parameter, and ADICP–total color difference correlations were found in forced air convection–, microwave-, and microwave–convection-dried samples, respectively. Microwave and microwave–convection drying achieved desirable protein quality associated with low-temperature drying at much shorter times. 相似文献
47.
Antonio Ieni Valeria Barresi Rosario Caltabiano Alessia Caleo Luca Reggiani Bonetti Salvatore Lanzafame Pio Zeppa Rosario Alberto Caruso Giovanni Tuccari 《International journal of molecular sciences》2014,15(12):22331-22341
Background: The assessment of human epidermal growth factor receptor 2 (HER2) gene amplification is essential in order to identify those patients affected by advanced gastric cancer who may benefit from Trastuzumab targeted therapy. Materials and Methods: With the aim to investigate the concordance rate in HER2 status between primary gastric carcinoma (GC) and synchronous lymphnode metastases, we investigated HER2 status in a cohort of 108 surgical formalin-fixed paraffin-embedded specimens of GC and matched synchronous metastatic lymph nodes collected from three different units of Anatomic Pathology in southern of Italy. Fleiss-Cohen weighted k statistics were used to assess the concordance rate of HER2 status. Results: HER2 amplification was observed in 17% of primary GCs and the overall concordance rate with corresponding nodal metastases was 90.74%. Changes in HER2 status between primary GC and matched synchronous metastases were evidenced in 10 (9.26%) cases. Of these, 6 cases were HER2 amplified in the primary GC and not amplified in the metastases, while 4 were HER2 not amplified in the primary tumour and amplified in the lymph node metastases. Conclusions: Although at present the simultaneous determination of HER2 in advanced gastric cancer and corresponding metastatic lymph nodes is not mandatory, the possibility that the synchronous metastases of GC have a different HER2 status from that of the primary tumour is of remarkable significance; Indeed this may have influence on the therapeutic management and prognosis of the patients. 相似文献
48.
Darío M González Raúl Quijada Mehrdad Yazdani‐Pedram Joao Paulo Lourenço M Rosario Ribeiro 《Polymer International》2016,65(3):320-326
MCM‐41 nanoparticles were used for preparing nanocomposites through the in situ polymerization of propylene. The performance of the catalytic system and the final properties of the materials obtained are highly dependent on the methodology used for impregnation of the catalyst onto the support particles, and therefore an optimization study for the impregnation methodology of the catalyst (Me2Si(Ind)2ZrCl2) was carried out. Two different methodologies were used; the results in terms of catalytic activity and polymer molecular masses indicated that the most promising one involved the pre‐activation of the catalyst with the cocatalyst, methylaluminoxane, followed by impregnation onto the MCM‐41 nanoparticles. Thus, an optimized route for the preparation of polypropylene nanocomposites achieving significant improvements in catalyst activity was developed. The nanocomposite materials were characterized by GPC, TGA and DSC. The dispersion state and the size of the nanoparticles incorporated in the polypropylene matrix were investigated by transmission electron microcopy. Additionally, this methodology allows simultaneous control of the desired amount of support and the concentration of catalyst to be used in the in situ polymerization. © 2015 Society of Chemical Industry 相似文献
49.
Ramn Cava Ruth Trrega Rosario Ramírez Juan Atanasio Carrasco 《Innovative Food Science and Emerging Technologies》2009,10(4):495-499
The effect of irradiation (0, 5 and 10 kGy) on the oxidative and colour stability of vacuum-packed Iberian dry-cured loin slices from pigs fed on concentrate feed (CON) or free-range reared (FRG) stored under refrigerated storage was studied. Irradiation treatment increased lipid oxidation, measured as TBA-RS values and hexanal content of dry-cured loins. It also increased redness (CIE a) and lightness (CIE L) of dry-cured loins. Refrigerated storage reduced the differences due to irradiation treatment of instrumental colour values like lightness. However, the decrease of redness during storage was more marked in irradiated than in non-irradiated dry-cured loin. Storage increased differences in TBA-RS values between irradiated and non-irradiated FRG dry-cured loin, while the opposite trend was found for CON dry-cured loins. In addition, no differences in the hexanal content were found after 30 days of refrigerated storage. Therefore, the storage of Iberian dry-cured loin in absence of oxygen by using a vacuum packaging could be an adequate method to reduce changes associated to irradiation treatment in Iberian dry-cured loin.
Industrial relevance
Iberian dry-cured loin is a high sensory quality meat product with increasing projection in external markets Irradiation has shown to be an effective method to control pathogen and spoilage microorganisms in meat and meat products. However, e-beam irradiation can promote colour and oxidation changes that could modify their sensory characteristics. The study aimed the evaluation of e-beam irradiation at two levels (5 and 10 kGy) — higher doses than those that could be necessary to control pathogen microorganisms in this kind of product — on colour changes and lipid oxidation at vacuum-packed slices of Iberian dry-cured loin during subsequent extended chilled storage. E-beam treatment induced changes in colour and lipid oxidation in sliced Iberian dry-cured loin immediately after treatment and subsequent refrigerated storage. 相似文献50.
Davide Barbagallo Angela Caponnetto Cristina Barbagallo Rosalia Battaglia Federica Mirabella Duilia Brex Michele Stella Giuseppe Broggi Roberto Altieri Francesco Certo Rosario Caltabiano Giuseppe Maria Vincenzo Barbagallo Carmelina Daniela Anfuso Gabriella Lupo Marco Ragusa Cinzia Di Pietro Thomas Birkballe Hansen Michele Purrello 《International journal of molecular sciences》2021,22(4)
Circular RNAs (circRNAs) are a large class of RNAs with regulatory functions within cells. We recently showed that circSMARCA5 is a tumor suppressor in glioblastoma multiforme (GBM) and acts as a decoy for Serine and Arginine Rich Splicing Factor 1 (SRSF1) through six predicted binding sites (BSs). Here we characterized RNA motifs functionally involved in the interaction between circSMARCA5 and SRSF1. Three different circSMARCA5 molecules (Mut1, Mut2, Mut3), each mutated in two predicted SRSF1 BSs at once, were obtained through PCR-based replacement of wild-type (WT) BS sequences and cloned in three independent pcDNA3 vectors. Mut1 significantly decreased its capability to interact with SRSF1 as compared to WT, based on the RNA immunoprecipitation assay. In silico analysis through the “Find Individual Motif Occurrences” (FIMO) algorithm showed GAUGAA as an experimentally validated SRSF1 binding motif significantly overrepresented within both predicted SRSF1 BSs mutated in Mut1 (q-value = 0.0011). U87MG and CAS-1, transfected with Mut1, significantly increased their migration with respect to controls transfected with WT, as revealed by the cell exclusion zone assay. Immortalized human brain microvascular endothelial cells (IM-HBMEC) exposed to conditioned medium (CM) harvested from U87MG and CAS-1 transfected with Mut1 significantly sprouted more than those treated with CM harvested from U87MG and CAS-1 transfected with WT, as shown by the tube formation assay. qRT-PCR showed that the intracellular pro- to anti-angiogenic Vascular Endothelial Growth Factor A (VEGFA) mRNA isoform ratio and the amount of total VEGFA mRNA secreted in CM significantly increased in Mut1-transfected CAS-1 as compared to controls transfected with WT. Our data suggest that GAUGAA is the RNA motif responsible for the interaction between circSMARCA5 and SRSF1 as well as for the circSMARCA5-mediated control of GBM cell migration and angiogenic potential. 相似文献